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The Chemical Softening Effect and Mechanism of Low Rank Coal Soaked in Alkaline Solution

  • Gao Zhixiang , Guo Hongyu EMAIL logo , Dong Zhiwei , Luo Yuan and Xia Daping
Published/Copyright: December 31, 2019
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Open Chemistry
From the journal Open Chemistry Volume 17 Issue 1

Abstract

In order to analyze the feasibility of chemical softening on low rank coals, bituminous coal was collected from the Qianqiu mine in Henan Province, China, and soaked in water and alkaline solution for different lengths of time. The complete stress-strain and acoustic emission (AE) experiments on the coal samples under uniaxial compression were tested on the RMT-150B Rock Mechanics Testing System and DS2 series AE signal analyzer. The results showed that the coal samples soaked in the water and alkaline solution present different characteristics in the deformation and failure process. As we increase the soaking time, the uniaxial compressive strength and deformation degree of the soaked coal samples in the alkaline solution and water decreased by 42.7% and 94.8% respectively. In the loading test, an AE signal is generated in all coal samples and the maximum ringing count rate and AE energy rate are present near the stress maximum for a short time. Moreover, the ringing count rate and AE energy rate have a good consistency with the stress-strain of the coal samples. The cumulative ringing count of the two groups soaked in water and alkaline solution decreased by 51% and 89% compared to the original coal sample. However, the decreased degree of the samples soaked in the alkaline solution is much higher than that of those soaked in water and the results showed that the alkaline solution has a better softening effect on the coal sample. With the increase of the alkaline solution concentration, the contact angle decreased from 112.5° to 41°. Through microscope and scanning electron microscopy (SEM) analysis of the soaked coal samples, we found that the pores and fissures increased, the structure of coal became loose, and the mechanical strength decreased sharply after soaking in the alkaline solution, thus achieving a chemical softening effect.

Keywords: alkaline solution; low rank coal; chemical softness; stress-strain behavior; acoustic emission characteristics

1 Introduction

In recent years China’s many mines have entered the deep mining stage as the mining scale has enlarged [1, 2, 3]. In the complicated geological environment of great buried depths and higher ground stress, due in part to the pressure from overlying strata, hard brittle coal rock easily acts as a higher energy storage rock mass [4]. Meanwhile, in the comprehensive top coal mining of hard and thick coal seams, the top coal can-not be sufficiently broken and collapsed in a timely manner by the mine pressure, thus making a significant amount of top coal difficult to recover, reducing the coal mining rate, and restricting productivity [5, 6, 7, 8, 9]. Many scholars have studied the damaging evolution process of coal and the relationship between the failure mode of coal, the degree of damage, and the confining pressure through acoustic emission (AE) experiments and theoretical research on uniaxial, double shaft, and other conditions [10, 11, 12, 13, 14, 15]. The results showed that the dynamic failure of hard coal is significantly stronger than that of soft coal [16, 17]. In order to eliminate the threat of hard coal, water pre-infusion is often used to weaken the hard top coal in underground coal mines and to decrease the mechanical strength of coal, improving the caving properties of top-coal and enhancing security of top coal caving in medium hardness thick coal seams [18, 19, 20]. However, water pre-infusion also has some current limitations, such as water can only fracture, loosen, lubricate, and destroy the internal microstructure of coal, but the speed of softening coal is relatively slow and the wettability is poor [21, 22]. Therefore, it is important to explore a new way to soften hard coal.

There is a significant amount of organic matter in low rank coals, which can react with an alkaline solution to change the physical structure significantly [23, 24]; sharply decrease the mechanical strength of coal, and even make the coal of high burst liability into non-burst liability. Therefore, the method of using an alkaline solution to chemically soften coal was presented [25]. In this paper, low rank coal from the Qianqiu mine in Henan Province was selected and used to perform an AE test in the process of compressed deformation and failure for different immersion times in water and alkaline solution. Based on the experiments, the stress-strain characteristics and the coupling relationship between the stress-strain and AE parameters of coal after different soaking times were analyzed to explore the feasibility and effect of chemical softening on coal with the alkaline solution. The inherent mechanism of the alkaline solution chemical softening is analyzed under a contact angle instrument, microscope, and scanning electron microscopy (SEM).

The study found a chemical control technology that is different from the traditional physical technology to prevent rock burst. The technology is of great practical significance for solving the problem of rock burst in middle and low rank coal mines, and the technology may extend the application of alkali solution to the field of coal mine disaster control, which is important for improving the safety level of coal mines in China and building intrinsically safe wells.

2 Experiment and Methods

2.1 Selection and Preparation of Coal

2.1.1 Samples

The coal samples were collected from the Qianqiu mine in Henan Province with serious rockburst. Proximate analysis was performed following American Society for Testing and Materials (ASTM) Standards D3173-11 (2011), D3174-11 (2011) and D3175-11 (2011). A reflectivity test was carried out according to the ASTM Standards D2798-11a (2011) (Table 1). These samples were processed into standard cylindrical specimens of φ50×100 mm in the laboratory (Figure 1).

Figure 1 Partial standard coal samples.
Figure 1

Partial standard coal samples.

Table 1

Coal sample information.

Source of coalMad/%Vdaf/%Ad/%Ro,ran/%Coal rank
Qianqiu mine0.9840.0110.310.56Bituminous

  1. M, moistore; V, volatile matter; A, ash yield; ad, air dry basis; daf, dry and ash-free basis; d, dry basis; Ro,ran, vitrinite random reflectance.

In order to research the effect of chemical softening on coal, we reduce the interference of coal samples on the experimental results and ensure the dense degree of the test coal samples is consistent. Coal samples with an acoustic velocity between 1416-1430 m/s were selected to test, according to the acoustic velocity index. Then the selected coal samples were divided into three groups. The original group was not soaked and numbered Y. Group A was soaked in water for 3, 5 and 7 days, respectively, numbered A3, A5, and A7. In contrast, group B was immersed in 0.5 mol/L NaOH solution, and numbered B3, B5, and B7 (Table 2).

Table 2

Test results of the acoustic velocity.

The original groupA groupB group
Sample numberVelocitySample numberVelocitySample numberVelocity
Y1427.47A31420.89B31416.37
A51428.23B51423.32
A71419.26B71429.34

2.2 Experimental Facilities

  1. The uniaxial compression coal experiments were conducted by the RMT-150B Rock Mechanics Testing System, which has two loading modes with axial compression and horizontal shear, a maximum vertical load of 1000 kN and a maximum horizontal static load of 500 kN, a triaxial testing apparatus with a maximum confining pressure of 50 MPa, maximum compression variation of 5 mm, and a maximum shearing deformation of 15 mm. The system was designed with a complete digital automatic control system, the test process was displayed real-time, and test data were collected automatically.

  2. We used the type of DS2 series AE signal analyzer (Type A; Beijing Softland Times Scientific and Technology Co. Ltd, China) running Windows XP with win7 (32 bit) operating system and USB 2.0 interface. The parameters of the analyzer are as follows: the sampling rate is 3 MHz, the passing rate of data is more than 48 Mb/s, the operating temperature range is 10℃~50℃, the working voltage is 220 V, and the A/D conversion accuracy is 16 bit. At the same time, it was equipped with a RS-35C integrative sensor, filter exteriorization, attenuator, and multichannel synchronous data acquisition system with the function of full waveform storage. The sampling frequency is 1000 kHz, the sampling length is 2048 Byte, and the threshold value of waveform is 40 dB.

  3. The contact angles were measured using a contact angle measurement tool (JC2000C1; Shanghai Zhongchen Digital Technology Co. Ltd, China) with a working voltage of 220 V, rated power of 50 Hz, reading measuring accuracy of 0.001 mm, and electronic temperature heating system to make the experimental temperature constant. The original coal and pulverized coal, which were soaked in different concentrations of the NaOH solution, were made into round calendaring plane test pieces with a mean thickness of 1 mm by using a pressure molding lapping tool to test the contact angle between the test piece and water.

  4. The polished powder coal of the smoothing surface was observed using a polarizing microscope (Axioskop 40 Pol; ZEISS JENA, Germany) with a reflective plane of polarized light×100. The original coal sample marked the observation point to ensure observation after exposure to the alkaline solution at the same position and a photo of the observation point was taken for comparison by the image analysis system.

  5. The SEM (JSM-6390LV; JEOL, Japan) was used to observe the coal structure. This instrument is equipped with a working voltage of 30 kV. The magnification is 30~300000, the resolution is 3 nm, and the imaging is a secondary electronic image (SEI).

2.3 Experimental Methods

In this study, the uniaxial compression test was loaded using the displacement control method with a loading rate 0.005 mm/min. The sampling interval of the RMT-150B Rock Mechanics Testing Machine, Digital Strain Data Acquisition Instrument, and AE Automonitoring System is 50 μs to ensure the axial compression, the deformation, and the AE signal of the testing coal are acquired synchronously. The AE sensor was connected on both sides of the coal sample before the experiment, and a layer of butter was coated on the contact position between the probe and coal. Then the probe is fixed with rubberized fabric to ensure the coupling effect. In order to eliminate the impact of environmental noise on the AE test, the noise threshold is set at 45 dB and the sampling threshold at 35 kHz, according to the previous test. During the experiment, the AE signal generated by the micro crack in the coal sample is recorded and drawn by the DS2 series AE signal analyzer. The axial compression of the coal sample is applied and recorded automatically by the RMT-150B Rock Mechanics Testing Machine, and the axial strain and the lateral strain are measured and displayed by the horizontal and radial strain gauges attached to the surface of the coal sample by means of the Digital Strain Data Acquisition Instrument.

Ethical approval: The conducted research is not related to either human or animal use.

3 Results

3.1 Comparative Analysis of Stress-Strain Characteristics and Cumulative Ringing Count and Time of Coal

The complete stress-strain curves of the samples under the uniaxial compression reflect the stress-strain feature of coal samples under loads. These curves for the coal samples soaking in water and alkaline solution for different times were drawn according to the experimental results (Figure 2). The relation curves for the cumulative ringing count for coal samples at different soaking times is shown in Figure 2.

Figure 2 Relationship between the stress and strain Cumulative ringing count of the coal samples (a) the original coal; (b) soaked for 3 days; (c) soaked for 5 days; (d) soaked for 7 days.
Figure 2

Relationship between the stress and strain Cumulative ringing count of the coal samples (a) the original coal; (b) soaked for 3 days; (c) soaked for 5 days; (d) soaked for 7 days.

We see from Figure 2 that the coal samples present different deformation features in the deformation and failure process because of the different soaking times. The strength of the original coal sample is the largest, and the deformation is larger for the entire failure process. Meanwhile, the pre-peak deformation is almost linear elastic, and the duration is longer. There is no symptom before the breaking of the coal samples, and the failure was accompanied with the fly out of fragments and the obvious sound of cracking. The duration of the elastic deformation stage duration in the stress-strain curve for coal samples is shorter after soaking in water or alkaline solution, compared to that of the original coal sample. The uniaxial compressive strength of the coal samples decreases gradually with the increase of soaking time. With prolonged soaking times, the uniaxial compressive strength of coal samples soaked in water decreased from 19.2 to 11, or 42.7%; while that of the coal soaked in the alkaline solution decreased sharply, from 19.2 to 1, or 94.8%. These results prove that the alkaline solution accelerated the softening process of the coal samples and reduced the compressive strength.

As seen in Figure 2, the cumulative ringing count of the two groups soaked in water and alkaline solution is decreased compared to the original coal sample. The cumulative ringing count of A7 decreased by 51%, compared to Y; while B7 decreased by 89%. This shows that the AE activity of the samples soaked in water and alkaline solution decreased during the loading test, which is related to how the coal sample was chemical softened. However, the AE activity of coal samples soaked in the alkaline solution is more significantly weakened, which indicates that the softening effect of the alkaline solution is best and the longer the soaking time, the greater the softening effect.

3.2 Analysis of Ringing Count Rate of Coal

The relation curves between the ringing count rate and the stress-strain under different soaking times is shown in Figure 3.

Figure 3 Relationship between the ringing count rate and the stress-strain (a) the original coal; (b) soaked for 3 days; (c) soaked for 5 days; (d) soaked for 7 days.
Figure 3

Relationship between the ringing count rate and the stress-strain (a) the original coal; (b) soaked for 3 days; (c) soaked for 5 days; (d) soaked for 7 days.

As seen in Figure 3, the softening effect of the coal samples soaked in the alkaline solution is significant, which reduces the strength of coal samples and prevents obvious cracks from formed inside coal sample, and the ringing count rate is nearly 0. The times of pore and fracture due to pressure compaction of other coal samples are short and the acoustic emission signals was less and relatively stable in the elastic deformation stage, the internal structure of coal sample was not changed obviously. The acoustic emission signals increased obviously in the microscopic split stage, and new micro-fracture in coal samples began to appear. When the coal sample was not completely destroyed, the new and old cracks in coal samples continued to develop and interlinked accompanied by the increasing of axial force, the ringing count rate increased in this process. Meanwhile, the AE signal is generated in the process of uniaxial compressive failure and the maximum of ringing count rate is present near the stress maximum for a short time. Meanwhile, the ringing count rate has a good consistency with the stress-strain of the coal samples. The ringing count rate of the soaked coal samples decreased as the time increased, which is in contrast with the original coal sample. However, the weakening tendency of the ringing count rate for the coal samples soaked in the alkaline solution is more obvious compared to that of coal samples soaked in water. The main reason for this is that the strong alkaline solution has a more significant softening effect, making the coal strength decrease and the AE activity weaken.

3.3 The AE Energy Analysis of Coal Samples

Based on the test results, the relation curves between the AE energy rate and the stress-strain of the coal samples under different soaking times are shown in Figure 4.

Figure 4 Relationship between the AE energy rate and the stress-strain of coal samples (a) the original coal; (b) soaked for 3 days; (c) soaked for 5 days; (d) soaked for 7 days.
Figure 4

Relationship between the AE energy rate and the stress-strain of coal samples (a) the original coal; (b) soaked for 3 days; (c) soaked for 5 days; (d) soaked for 7 days.

From Figure 3 and Figure 4, we see that the energy rate has a good consistency with the ringing count rate. At the initial loading stage, AE activities of different degree and minimum events begin to be produced, and the ringing count and energy lessen. However, as time increases, the AE energy increases. Compared with the original coal sample, we find that, in the soaked coal samples, the maximum AE energy rate is present near the stress maximum for a short time, before and after failure. However, the tendency is more obvious for the coal samples soaked in the alkaline solution than in those soaked in water.

4 Discussion

4.1 Contact Angle Test

The contact angle can validate the hydrophilicity and wettability of coal [26]. In order to analyze the mechanism of the alkaline solution softening coal, the proper bituminous coal was pulverized into a 200 mesh and soaked with 0.2 mol/L, 0.5 mol/L, and 1 mol/L NaOH solution for 5 days. Then the coal sample was cleaned, centrifuged, and dried with the original coal sample. After this, the pulverized coal was made into round calendaring plane test pieces with a mean thickness of 1 mm by using a pressure molding lapping tool. Then the contact angle between the test piece and clear water were tested by the JC2000C1 contact angle measurement. Each test piece was measured 5 times and an average was applied. The test results are shown in Table 3 and Figure 5.

Figure 5 The trend of the contact angle of coal soaked in different concentrations of alkaline solution (a) the original coal; (b) 0.2 mol/L NaOH; (c) 0.5 mol/L NaOH; (d) 1 mol/L NaOH.
Figure 5

The trend of the contact angle of coal soaked in different concentrations of alkaline solution (a) the original coal; (b) 0.2 mol/L NaOH; (c) 0.5 mol/L NaOH; (d) 1 mol/L NaOH.

Table 3

Test results of contact angle between water and coal soaked in alkaline solution (°).

Coal sampleThe original coal0.2 mol/L NaOH0.5mol/L NaOH1 mol/L NaOH
Bituminous112.562.54741

The contact angle between the original coal and water was more than 90°, as seen in Table 3, showing strong hydrophobicity and poor wettability. The contact angle between water and coal soaked in the alkaline solution is sharply reduced, which indicates that the hydrophilicity and the wettability of the coal sample increases. In addition, with the increase of the alkaline solution concentration, the contact angle decreased from 112.5° to 41°. The immersion in the alkaline solution increases the hydrophilicity and wettability, which is more beneficial to coal softening.

4.2 Surface Observation Experiment

The bituminous sample was selected and prepared into two small pieces coal of 2 cm×2 cm×1 cm. One was observed under the optical microscope after being coarse-ground, fine-ground, and polished. In order to observe the same position on the coal surface, the observation point was photographed and recorded in advance. Then, the same coal was soaked in 0.5 mol/L NaOH solution, and observed at the same point to contrast the changes of before and after treatment with the alkaline solution (Figure 6 (a) and Figure 6 (b)). The other piece of coal was placed into a pumped vacuum, platted with gold, and then observed under SEM to compare the structure changes after being treated with 0.5 mol/L NaOH solution (Figure 6 (c) and Figure 6 (d)).

Figure 6 Surface observation of coal before and after NaOH solution treatment (a) the original coal observed by microscope (100×); (b) 0.5 mol/L NaOH soaked coal observed by microscope (100×); (c) the original coal observed by SEM (4000×); (d) 0.5 mol/L NaOH soaked coal observed by SEM (4000×).
Figure 6

Surface observation of coal before and after NaOH solution treatment (a) the original coal observed by microscope (100×); (b) 0.5 mol/L NaOH soaked coal observed by microscope (100×); (c) the original coal observed by SEM (4000×); (d) 0.5 mol/L NaOH soaked coal observed by SEM (4000×).

By comparing the structure of the coal sample before and after treatment with the alkaline solution in Figure 6, we found that the surface of the original coal sample was flat and smooth. However, the surface structure of the coal sample changed greatly after soaking in the alkaline solution. The surface was etched, surface roughness increased markedly, and more microporosity appeared. A large number of deep hole-like pores were distributed, pores and fissure connectivity greatly increased, and the coal structure became relatively loose, which further proved that the coal had softened [27].

4.3 Advantages of the Chemical Softening of Low Rank Coal Soaked in Alkaline Solution

The uniaxial compressive strength and deformation degree of samples soaked in the alkaline solution is smaller, indicating that the destructive effect of the alkaline solution to mechanical strength of coal sample is more obvious than that of water.

The reducing tendency of AE activity for samples soaked in the alkaline solution was obvious and the cumulative ringing count is far less than that of those soaked in water. Moreover, the ringing count rate and AE energy rate has a good consistency with the stress-strain of coal samples and it decreased as the time increased, but the decreased degree of those soaked in the alkaline solution is much higher than that of those soaked in water.

The alkaline solution has a better softening effect on the coal sample and the softening mechanism is different from that of water. The main reason is that alkali solution molecules seeped into coal structure which causes more small molecular organic matter dissolve out from the coal [28], and the humic acid organic substances in low rank coals react with the alkaline solution [29, 30], thus greatly increase the porosity and sharply decrease the mechanical strength. The chemical softening effect is more obvious than that of water.

5 Conclusions

With the increase of soaking time, the uniaxial compressive strength of all coal samples decrease gradually, but the uniaxial compressive strength of alkali-soaked coal sample is lower than that of original coal sample and water-soaked coal sample, and the degree of deformation is larger. The destructive effect of the alkaline solution to mechanical strength of coal sample is more obvious than that of water. The decreased degree of ringing count rate and AE energy rate soaked in the alkaline solution is much higher than that of those soaked in water. The chemical softening effect of coal soaked in alkaline solution is more obvious than that of water. The study has great significance in the study of using alkaline solution for preventing rook burst and top coal caving. This study can provide theoretical reference for high gas mine, coal and gas outburst mine and fully mechanized caving face with shock bumps and guarantee for safety production of coal mine.

Acknowledgements

This study was funded by the National Natural Science Foundation of China (Grant no. 41972178), the Fundamental Research Funds for the Universities of Henan Province (NSFRF180301), and Scientific and Technological Research Projects of Henan Province (Grant no.182300410004, 182102310845 and 192102310196). Moreover, the authors are grateful to the editor and anonymous reviewers of this paper.

  1. Conflict of interest: Authors declare no conflict of interest.

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Received: 2018-08-17
Accepted: 2019-08-17
Published Online: 2019-12-31

© 2019 Guo Hongyu et al., published by De Gruyter

This work is licensed under the Creative Commons Attribution 4.0 Public License.

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  25. Aqueous Micro-hydration of Na+(H2O)n=1-7 Clusters: DFT Study
  26. A proposed image-based detection of methamidophos pesticide using peroxyoxalate chemiluminescence system
  27. Phytochemical screening and estrogenic activity of total glycosides of Cistanche deserticola
  28. Biological evaluation of a series of benzothiazole derivatives as mosquitocidal agents
  29. Chemical pretreatments of Trapa bispinosa's peel (TBP) biosorbent to enhance adsorption capacity for Pb(ll)
  30. Dynamic Changes in MMP1 and TIMP1 in the Antifibrotic Process of Dahuang Zhechong Pill in Rats with Liver Fibrosis
  31. The Optimization and Production of Ginkgolide B Lipid Microemulsion
  32. Photodynamic Therapy Enhanced the Antitumor Effects of Berberine on HeLa Cells
  33. Chiral and Achiral Enantiomeric Separation of (±)-Alprenolol
  34. Correlation of Water Fluoride with Body Fluids, Dental Fluorosis and FT4, FT3 –TSH Disruption among Children in an Endemic Fluorosis area in Pakistan
  35. A one-step incubation ELISA kit for rapid determination of dibutyl phthalate in water, beverage and liquor
  36. Free Radical Scavenging Activity of Essential Oil of Eugenia caryophylata from Amboina Island and Derivatives of Eugenol
  37. Effects of Blue and Red Light On Growth And Nitrate Metabolism In Pakchoi
  38. miRNA-199a-5p functions as a tumor suppressor in prolactinomas
  39. Solar photodegradation of carbamazepine from aqueous solutions using a compound parabolic concentrator equipped with a sun tracking system
  40. Influence of sub-inhibitory concentration of selected plant essential oils on the physical and biochemical properties of Pseudomonas orientalis
  41. Preparation and spectroscopic studies of Fe(II), Ru(II), Pd(II) and Zn(II) complexes of Schiff base containing terephthalaldehyde and their transfer hydrogenation and Suzuki-Miyaura coupling reaction
  42. Complex formation in a liquid-liquid extraction-chromogenic system for vanadium(IV)
  43. Synthesis, characterization (IR, 1H, 13C & 31P NMR), fungicidal, herbicidal and molecular docking evaluation of steroid phosphorus compounds
  44. Analysis and Biological Evaluation of Arisaema Amuremse Maxim Essential Oil
  45. A preliminary assessment of potential ecological risk and soil contamination by heavy metals around a cement factory, western Saudi Arabia
  46. Anti- inflammatory effect of Prunus tomentosa Thunb total flavones in LPS-induced RAW264.7 cells
  47. Collaborative Influence of Elevated CO2 Concentration and High Temperature on Potato Biomass Accumulation and Characteristics
  48. Methods of extraction, physicochemical properties of alginates and their applications in biomedical field – a review
  49. Characteristics of liposomes derived from egg yolk
  50. Preparation of ternary ZnO/Ag/cellulose and its enhanced photocatalytic degradation property on phenol and benzene in VOCs
  51. Influence of Human Serum Albumin Glycation on the Binding Affinities for Natural Flavonoids
  52. Synthesis and antioxidant activity of 2-methylthio-pyrido[3,2-e][1,2,4] triazolo[1,5-a]pyrimidines
  53. Comparative study on the antioxidant activities of ten common flower teas from China
  54. Molecular Properties of Symmetrical Networks Using Topological Polynomials
  55. Synthesis of Co3O4 Nano Aggregates by Co-precipitation Method and its Catalytic and Fuel Additive Applications
  56. Phytochemical analysis, Antioxidant and Antiprotoscolices potential of ethanol extracts of selected plants species against Echinococcus granulosus: In-vitro study
  57. Silver nanoparticles enhanced fluorescence for sensitive determination of fluoroquinolones in water solutions
  58. Simultaneous Quantification of the New Psychoactive Substances 3-FMC, 3-FPM, 4-CEC, and 4-BMC in Human Blood using GC-MS
  59. Biodiesel Production by Lipids From Indonesian strain of Microalgae Chlorella vulgaris
  60. Miscibility studies of polystyrene/polyvinyl chloride blend in presence of organoclay
  61. Antibacterial Activities of Transition Metal complexes of Mesocyclic Amidine 1,4-diazacycloheptane (DACH)
  62. Novel 1,8-Naphthyridine Derivatives: Design, Synthesis and in vitro screening of their cytotoxic activity against MCF7 cell line
  63. Investigation of Stress Corrosion Cracking Behaviour of Mg-Al-Zn Alloys in Different pH Environments by SSRT Method
  64. Various Combinations of Flame Retardants for Poly (vinyl chloride)
  65. Phenolic compounds and biological activities of rye (Secale cereale L.) grains
  66. Oxidative degradation of gentamicin present in water by an electro-Fenton process and biodegradability improvement
  67. Optimizing Suitable Conditions for the Removal of Ammonium Nitrogen by a Microbe Isolated from Chicken Manure
  68. Anti-inflammatory, antipyretic, analgesic, and antioxidant activities of Haloxylon salicornicum aqueous fraction
  69. The anti-corrosion behaviour of Satureja montana L. extract on iron in NaCl solution
  70. Interleukin-4, hemopexin, and lipoprotein-associated phospholipase A2 are significantly increased in patients with unstable carotid plaque
  71. A comparative study of the crystal structures of 2-(4-(2-(4-(3-chlorophenyl)pipera -zinyl)ethyl) benzyl)isoindoline-1,3-dione by synchrotron radiation X-ray powder diffraction and single-crystal X-ray diffraction
  72. Conceptual DFT as a Novel Chemoinformatics Tool for Studying the Chemical Reactivity Properties of the Amatoxin Family of Fungal Peptides
  73. Occurrence of Aflatoxin M1 in Milk-based Mithae samples from Pakistan
  74. Kinetics of Iron Removal From Ti-Extraction Blast Furnace Slag by Chlorination Calcination
  75. Increasing the activity of DNAzyme based on the telomeric sequence: 2’-OMe-RNA and LNA modifications
  76. Exploring the optoelectronic properties of a chromene-appended pyrimidone derivative for photovoltaic applications
  77. Effect of He Qi San on DNA Methylation in Type 2 Diabetes Mellitus Patients with Phlegm-blood Stasis Syndrome
  78. Cyclodextrin potentiometric sensors based on selective recognition sites for procainamide: Comparative and theoretical study
  79. Greener synthesis of dimethyl carbonate from carbon dioxide and methanol using a tunable ionic liquid catalyst
  80. Nonisothermal Cold Crystallization Kinetics of Poly(lactic acid)/Bacterial Poly(hydroxyoctanoate) (PHO)/Talc
  81. Enhanced adsorption of sulfonamide antibiotics in water by modified biochar derived from bagasse
  82. Study on the Mechanism of Shugan Xiaozhi Fang on Cells with Non-alcoholic Fatty Liver Disease
  83. Comparative Effects of Salt and Alkali Stress on Antioxidant System in Cotton (Gossypium Hirsutum L.) Leaves
  84. Optimization of chromatographic systems for analysis of selected psychotropic drugs and their metabolites in serum and saliva by HPLC in order to monitor therapeutic drugs
  85. Electrocatalytic Properties of Ni-Doped BaFe12O19 for Oxygen Evolution in Alkaline Solution
  86. Study on the removal of high contents of ammonium from piggery wastewater by clinoptilolite and the corresponding mechanisms
  87. Phytochemistry and toxicological assessment of Bryonia dioica roots used in north-African alternative medicine
  88. The essential oil composition of selected Hemerocallis cultivars and their biological activity
  89. Mechanical Properties of Carbon Fiber Reinforced Nanocrystalline Nickel Composite Electroforming Deposit
  90. Anti-c-myc efficacy block EGFL7 induced prolactinoma tumorigenesis
  91. Topical Issue on Applications of Mathematics in Chemistry
  92. Zagreb Connection Number Index of Nanotubes and Regular Hexagonal Lattice
  93. The Sanskruti index of trees and unicyclic graphs
  94. Valency-based molecular descriptors of Bakelite network BNmn
  95. Computing Topological Indices for Para-Line Graphs of Anthracene
  96. Zagreb Polynomials and redefined Zagreb indices of Dendrimers and Polyomino Chains
  97. Topological Descriptor of 2-Dimensional Silicon Carbons and Their Applications
  98. Topological invariants for the line graphs of some classes of graphs
  99. Words for maximal Subgroups of Fi24‘
  100. Generators of Maximal Subgroups of Harada-Norton and some Linear Groups
  101. Special Issue on POKOCHA 2018
  102. Influence of Production Parameters on the Content of Polyphenolic Compounds in Extruded Porridge Enriched with Chokeberry Fruit (Aronia melanocarpa (Michx.) Elliott)
  103. Effects of Supercritical Carbon Dioxide Extraction (SC-CO2) on the content of tiliroside in the extracts from Tilia L. flowers
  104. Impact of xanthan gum addition on phenolic acids composition and selected properties of new gluten-free maize-field bean pasta
  105. Impact of storage temperature and time on Moldavian dragonhead oil – spectroscopic and chemometric analysis
  106. The effect of selected substances on the stability of standard solutions in voltammetric analysis of ascorbic acid in fruit juices
  107. Determination of the content of Pb, Cd, Cu, Zn in dairy products from various regions of Poland
  108. Special Issue on IC3PE 2018 Conference
  109. The Photocatalytic Activity of Zns-TiO2 on a Carbon Fiber Prepared by Chemical Bath Deposition
  110. N-octyl chitosan derivatives as amphiphilic carrier agents for herbicide formulations
  111. Kinetics and Mechanistic Study of Hydrolysis of Adenosine Monophosphate Disodium Salt (AMPNa2) in Acidic and Alkaline Media
  112. Antimalarial Activity of Andrographis Paniculata Ness‘s N-hexane Extract and Its Major Compounds
  113. Special Issue on ABB2018 Conference
  114. Special Issue on ICCESEN 2017
  115. Theoretical Diagnostics of Second and Third-order Hyperpolarizabilities of Several Acid Derivatives
  116. Determination of Gamma Rays Efficiency Against Rhizoctonia solani in Potatoes
  117. Studies On Compatibilization Of Recycled Polyethylene/Thermoplastic Starch Blends By Using Different Compatibilizer
  118. Liquid−Liquid Extraction of Linalool from Methyl Eugenol with 1-Ethyl-3-methylimidazolium Hydrogen Sulfate [EMIM][HSO4] Ionic Liquid
  119. Synthesis of Graphene Oxide Through Ultrasonic Assisted Electrochemical Exfoliation
  120. Special Issue on ISCMP 2018
  121. Synthesis and antiproliferative evaluation of some 1,4-naphthoquinone derivatives against human cervical cancer cells
  122. The influence of the grafted aryl groups on the solvation properties of the graphyne and graphdiyne - a MD study
  123. Electrochemical modification of platinum and glassy carbon surfaces with pyridine layers and their use as complexing agents for copper (II) ions
  124. Effect of Electrospinning Process on Total Antioxidant Activity of Electrospun Nanofibers Containing Grape Seed Extract
  125. Effect Of Thermal Treatment Of Trepel At Temperature Range 800-1200˚C
  126. Topical Issue on Agriculture
  127. The effect of Cladophora glomerata exudates on the amino acid composition of Cladophora fracta and Rhizoclonium sp.
  128. Influence of the Static Magnetic Field and Algal Extract on the Germination of Soybean Seeds
  129. The use of UV-induced fluorescence for the assessment of homogeneity of granular mixtures
  130. The use of microorganisms as bio-fertilizers in the cultivation of white lupine
  131. Lyophilized apples on flax oil and ethyl esters of flax oil - stability and antioxidant evaluation
  132. Production of phosphorus biofertilizer based on the renewable materials in large laboratory scale
  133. Human health risk assessment of potential toxic elements in paddy soil and rice (Oryza sativa) from Ugbawka fields, Enugu, Nigeria
  134. Recovery of phosphates(V) from wastewaters of different chemical composition
  135. Special Issue on the 4th Green Chemistry 2018
  136. Dead zone for hydrogenation of propylene reaction carried out on commercial catalyst pellets
  137. Improved thermally stable oligoetherols from 6-aminouracil, ethylene carbonate and boric acid
  138. The role of a chemical loop in removal of hazardous contaminants from coke oven wastewater during its treatment
  139. Combating paraben pollution in surface waters with a variety of photocatalyzed systems: Looking for the most efficient technology
  140. Special Issue on Chemistry Today for Tomorrow 2019
  141. Applying Discriminant and Cluster Analyses to Separate Allergenic from Non-allergenic Proteins
  142. Chemometric Expertise Of Clinical Monitoring Data Of Prolactinoma Patients
  143. Chemomertic Risk Assessment of Soil Pollution
  144. New composite sorbent for speciation analysis of soluble chromium in textiles
  145. Photocatalytic activity of NiFe2O4 and Zn0.5Ni0.5Fe2O4 modified by Eu(III) and Tb(III) for decomposition of Malachite Green
  146. Photophysical and antibacterial activity of light-activated quaternary eosin Y
  147. Spectral properties and biological activity of La(III) and Nd(III) Monensinates
  148. Special Issue on Monitoring, Risk Assessment and Sustainable Management for the Exposure to Environmental Toxins
  149. Soil organic carbon mineralization in relation to microbial dynamics in subtropical red soils dominated by differently sized aggregates
  150. A potential reusable fluorescent aptasensor based on magnetic nanoparticles for ochratoxin A analysis
  151. Special Issue on 13th JCC 2018
  152. Fluorescence study of 5-nitroisatin Schiff base immobilized on SBA-15 for sensing Fe3+
  153. Thermal and Morphology Properties of Cellulose Nanofiber from TEMPO-oxidized Lower part of Empty Fruit Bunches (LEFB)
  154. Encapsulation of Vitamin C in Sesame Liposomes: Computational and Experimental Studies
  155. A comparative study of the utilization of synthetic foaming agent and aluminum powder as pore-forming agents in lightweight geopolymer synthesis
  156. Synthesis of high surface area mesoporous silica SBA-15 by adjusting hydrothermal treatment time and the amount of polyvinyl alcohol
  157. Review of large-pore mesostructured cellular foam (MCF) silica and its applications
  158. Ion Exchange of Benzoate in Ni-Al-Benzoate Layered Double Hydroxide by Amoxicillin
  159. Synthesis And Characterization Of CoMo/Mordenite Catalyst For Hydrotreatment Of Lignin Compound Models
  160. Production of Biodiesel from Nyamplung (Calophyllum inophyllum L.) using Microwave with CaO Catalyst from Eggshell Waste: Optimization of Transesterification Process Parameters
  161. The Study of the Optical Properties of C60 Fullerene in Different Organic Solvents
  162. Composite Material Consisting of HKUST-1 and Indonesian Activated Natural Zeolite and its Application in CO2 Capture
  163. Topical Issue on Environmental Chemistry
  164. Ionic liquids modified cobalt/ZSM-5 as a highly efficient catalyst for enhancing the selectivity towards KA oil in the aerobic oxidation of cyclohexane
  165. Application of Thermal Resistant Gemini Surfactants in Highly Thixotropic Water-in-oil Drilling Fluid System
  166. Screening Study on Rheological Behavior and Phase Transition Point of Polymer-containing Fluids produced under the Oil Freezing Point Temperature
  167. The Chemical Softening Effect and Mechanism of Low Rank Coal Soaked in Alkaline Solution
  168. The Influence Of NO/O2 On The NOx Storage Properties Over A Pt-Ba-Ce/γ-Al2O3 Catalyst
  169. Special Issue on the International conference CosCI 2018
  170. Design of SiO2/TiO2 that Synergistically Increases The Hydrophobicity of Methyltrimethoxysilane Coated Glass
  171. Antidiabetes and Antioxidant agents from Clausena excavata root as medicinal plant of Myanmar
  172. Development of a Gold Immunochromatographic Assay Method Using Candida Biofilm Antigen as a Bioreceptor for Candidiasis in Rats
  173. Special Issue on Applied Biochemistry and Biotechnology 2019
  174. Adsorption of copper ions on Magnolia officinalis residues after solid-phase fermentation with Phanerochaete chrysosporium
  175. Erratum
  176. Erratum to: Sand Dune Characterization For Preparing Metallurgical Grade Silicon
https://doi.org/10.1515/chem-2019-0148
Keywords for this article
alkaline solution; low rank coal; chemical softness; stress-strain behavior; acoustic emission characteristics
Creative Commons
BY 4.0

Articles in the same Issue

  1. Regular Articles
  2. Research on correlation of compositions with oestrogenic activity of Cistanche based on LC/Q-TOF-MS/MS technology
  3. Efficacy of Pyrus elaeagnifolia subsp. elaeagnifolia in acetic acid–induced colitis model
  4. Anti-inflammatory and antinociceptive features of Bryonia alba L.: As a possible alternative in treating rheumatism
  5. High efficiency liposome fusion induced by reducing undesired membrane peptides interaction
  6. Prediction of the Blood-Brain Barrier Permeability Using RP-18 Thin Layer Chromatography
  7. Phytic Acid Extracted from Rice Bran as a Growth Promoter for Euglena gracilis
  8. Development of a validated spectrofluorimetric method for assay of sotalol hydrochloride in tablets and human plasma: application for stability-indicating studies
  9. Topological Indices of Hyaluronic Acid-Paclitaxel Conjugates’ Molecular Structure in Cancer Treatment
  10. Thermodynamic properties of the bubble growth process in a pool boiling of water-ethanol mixture two-component system
  11. Critical Roles of the PI3K-Akt-mTOR Signaling Pathway in Apoptosis and Autophagy of Astrocytes Induced by Methamphetamine
  12. Characteristics of Stable Hydrogen and Oxygen Isotopes of Soil Moisture under Different Land Use in Dry Hot Valley of Yuanmou
  13. Specific, highly sensitive and simple spectrofluorimetric method for quantification of daclatasvir in HCV human plasma patients and in tablets dosage form
  14. Chromium-modified cobalt molybdenum nitrides as catalysts for ammonia synthesis
  15. Langerhans cell-like dendritic cells treated with ginsenoside Rh2 regulate the differentiation of Th1 and Th2 cells in vivo
  16. Identification of Powdery Mildew Blumeria graminis f. sp. tritici Resistance Genes in Selected Wheat Varieties and Development of Multiplex PCR
  17. Computational Analysis of new Degree-based descriptors of oxide networks
  18. The Use Of Chemical Composition And Additives To Classify Petrol And Diesel Using Gas Chromatography–Mass Spectrometry And Chemometric Analysis: A Uk Study
  19. Minimal Energy Tree with 4 Branched Vertices
  20. Jatropha seed oil derived poly(esteramide-urethane)/ fumed silica nanocomposite coatings for corrosion protection
  21. Calculating topological indices of certain OTIS interconnection networks
  22. Energy storage analysis of R125 in UIO-66 and MOF-5 nanoparticles: A molecular simulation study
  23. Velvet Antler compounds targeting major cell signaling pathways in osteosarcoma - a new insight into mediating the process of invasion and metastasis in OS
  24. Effects of Azadirachta Indica Leaf Extract, Capping Agents, on the Synthesis of Pure And Cu Doped ZnO-Nanoparticles: A Green Approach and Microbial Activity
  25. Aqueous Micro-hydration of Na+(H2O)n=1-7 Clusters: DFT Study
  26. A proposed image-based detection of methamidophos pesticide using peroxyoxalate chemiluminescence system
  27. Phytochemical screening and estrogenic activity of total glycosides of Cistanche deserticola
  28. Biological evaluation of a series of benzothiazole derivatives as mosquitocidal agents
  29. Chemical pretreatments of Trapa bispinosa's peel (TBP) biosorbent to enhance adsorption capacity for Pb(ll)
  30. Dynamic Changes in MMP1 and TIMP1 in the Antifibrotic Process of Dahuang Zhechong Pill in Rats with Liver Fibrosis
  31. The Optimization and Production of Ginkgolide B Lipid Microemulsion
  32. Photodynamic Therapy Enhanced the Antitumor Effects of Berberine on HeLa Cells
  33. Chiral and Achiral Enantiomeric Separation of (±)-Alprenolol
  34. Correlation of Water Fluoride with Body Fluids, Dental Fluorosis and FT4, FT3 –TSH Disruption among Children in an Endemic Fluorosis area in Pakistan
  35. A one-step incubation ELISA kit for rapid determination of dibutyl phthalate in water, beverage and liquor
  36. Free Radical Scavenging Activity of Essential Oil of Eugenia caryophylata from Amboina Island and Derivatives of Eugenol
  37. Effects of Blue and Red Light On Growth And Nitrate Metabolism In Pakchoi
  38. miRNA-199a-5p functions as a tumor suppressor in prolactinomas
  39. Solar photodegradation of carbamazepine from aqueous solutions using a compound parabolic concentrator equipped with a sun tracking system
  40. Influence of sub-inhibitory concentration of selected plant essential oils on the physical and biochemical properties of Pseudomonas orientalis
  41. Preparation and spectroscopic studies of Fe(II), Ru(II), Pd(II) and Zn(II) complexes of Schiff base containing terephthalaldehyde and their transfer hydrogenation and Suzuki-Miyaura coupling reaction
  42. Complex formation in a liquid-liquid extraction-chromogenic system for vanadium(IV)
  43. Synthesis, characterization (IR, 1H, 13C & 31P NMR), fungicidal, herbicidal and molecular docking evaluation of steroid phosphorus compounds
  44. Analysis and Biological Evaluation of Arisaema Amuremse Maxim Essential Oil
  45. A preliminary assessment of potential ecological risk and soil contamination by heavy metals around a cement factory, western Saudi Arabia
  46. Anti- inflammatory effect of Prunus tomentosa Thunb total flavones in LPS-induced RAW264.7 cells
  47. Collaborative Influence of Elevated CO2 Concentration and High Temperature on Potato Biomass Accumulation and Characteristics
  48. Methods of extraction, physicochemical properties of alginates and their applications in biomedical field – a review
  49. Characteristics of liposomes derived from egg yolk
  50. Preparation of ternary ZnO/Ag/cellulose and its enhanced photocatalytic degradation property on phenol and benzene in VOCs
  51. Influence of Human Serum Albumin Glycation on the Binding Affinities for Natural Flavonoids
  52. Synthesis and antioxidant activity of 2-methylthio-pyrido[3,2-e][1,2,4] triazolo[1,5-a]pyrimidines
  53. Comparative study on the antioxidant activities of ten common flower teas from China
  54. Molecular Properties of Symmetrical Networks Using Topological Polynomials
  55. Synthesis of Co3O4 Nano Aggregates by Co-precipitation Method and its Catalytic and Fuel Additive Applications
  56. Phytochemical analysis, Antioxidant and Antiprotoscolices potential of ethanol extracts of selected plants species against Echinococcus granulosus: In-vitro study
  57. Silver nanoparticles enhanced fluorescence for sensitive determination of fluoroquinolones in water solutions
  58. Simultaneous Quantification of the New Psychoactive Substances 3-FMC, 3-FPM, 4-CEC, and 4-BMC in Human Blood using GC-MS
  59. Biodiesel Production by Lipids From Indonesian strain of Microalgae Chlorella vulgaris
  60. Miscibility studies of polystyrene/polyvinyl chloride blend in presence of organoclay
  61. Antibacterial Activities of Transition Metal complexes of Mesocyclic Amidine 1,4-diazacycloheptane (DACH)
  62. Novel 1,8-Naphthyridine Derivatives: Design, Synthesis and in vitro screening of their cytotoxic activity against MCF7 cell line
  63. Investigation of Stress Corrosion Cracking Behaviour of Mg-Al-Zn Alloys in Different pH Environments by SSRT Method
  64. Various Combinations of Flame Retardants for Poly (vinyl chloride)
  65. Phenolic compounds and biological activities of rye (Secale cereale L.) grains
  66. Oxidative degradation of gentamicin present in water by an electro-Fenton process and biodegradability improvement
  67. Optimizing Suitable Conditions for the Removal of Ammonium Nitrogen by a Microbe Isolated from Chicken Manure
  68. Anti-inflammatory, antipyretic, analgesic, and antioxidant activities of Haloxylon salicornicum aqueous fraction
  69. The anti-corrosion behaviour of Satureja montana L. extract on iron in NaCl solution
  70. Interleukin-4, hemopexin, and lipoprotein-associated phospholipase A2 are significantly increased in patients with unstable carotid plaque
  71. A comparative study of the crystal structures of 2-(4-(2-(4-(3-chlorophenyl)pipera -zinyl)ethyl) benzyl)isoindoline-1,3-dione by synchrotron radiation X-ray powder diffraction and single-crystal X-ray diffraction
  72. Conceptual DFT as a Novel Chemoinformatics Tool for Studying the Chemical Reactivity Properties of the Amatoxin Family of Fungal Peptides
  73. Occurrence of Aflatoxin M1 in Milk-based Mithae samples from Pakistan
  74. Kinetics of Iron Removal From Ti-Extraction Blast Furnace Slag by Chlorination Calcination
  75. Increasing the activity of DNAzyme based on the telomeric sequence: 2’-OMe-RNA and LNA modifications
  76. Exploring the optoelectronic properties of a chromene-appended pyrimidone derivative for photovoltaic applications
  77. Effect of He Qi San on DNA Methylation in Type 2 Diabetes Mellitus Patients with Phlegm-blood Stasis Syndrome
  78. Cyclodextrin potentiometric sensors based on selective recognition sites for procainamide: Comparative and theoretical study
  79. Greener synthesis of dimethyl carbonate from carbon dioxide and methanol using a tunable ionic liquid catalyst
  80. Nonisothermal Cold Crystallization Kinetics of Poly(lactic acid)/Bacterial Poly(hydroxyoctanoate) (PHO)/Talc
  81. Enhanced adsorption of sulfonamide antibiotics in water by modified biochar derived from bagasse
  82. Study on the Mechanism of Shugan Xiaozhi Fang on Cells with Non-alcoholic Fatty Liver Disease
  83. Comparative Effects of Salt and Alkali Stress on Antioxidant System in Cotton (Gossypium Hirsutum L.) Leaves
  84. Optimization of chromatographic systems for analysis of selected psychotropic drugs and their metabolites in serum and saliva by HPLC in order to monitor therapeutic drugs
  85. Electrocatalytic Properties of Ni-Doped BaFe12O19 for Oxygen Evolution in Alkaline Solution
  86. Study on the removal of high contents of ammonium from piggery wastewater by clinoptilolite and the corresponding mechanisms
  87. Phytochemistry and toxicological assessment of Bryonia dioica roots used in north-African alternative medicine
  88. The essential oil composition of selected Hemerocallis cultivars and their biological activity
  89. Mechanical Properties of Carbon Fiber Reinforced Nanocrystalline Nickel Composite Electroforming Deposit
  90. Anti-c-myc efficacy block EGFL7 induced prolactinoma tumorigenesis
  91. Topical Issue on Applications of Mathematics in Chemistry
  92. Zagreb Connection Number Index of Nanotubes and Regular Hexagonal Lattice
  93. The Sanskruti index of trees and unicyclic graphs
  94. Valency-based molecular descriptors of Bakelite network BNmn
  95. Computing Topological Indices for Para-Line Graphs of Anthracene
  96. Zagreb Polynomials and redefined Zagreb indices of Dendrimers and Polyomino Chains
  97. Topological Descriptor of 2-Dimensional Silicon Carbons and Their Applications
  98. Topological invariants for the line graphs of some classes of graphs
  99. Words for maximal Subgroups of Fi24‘
  100. Generators of Maximal Subgroups of Harada-Norton and some Linear Groups
  101. Special Issue on POKOCHA 2018
  102. Influence of Production Parameters on the Content of Polyphenolic Compounds in Extruded Porridge Enriched with Chokeberry Fruit (Aronia melanocarpa (Michx.) Elliott)
  103. Effects of Supercritical Carbon Dioxide Extraction (SC-CO2) on the content of tiliroside in the extracts from Tilia L. flowers
  104. Impact of xanthan gum addition on phenolic acids composition and selected properties of new gluten-free maize-field bean pasta
  105. Impact of storage temperature and time on Moldavian dragonhead oil – spectroscopic and chemometric analysis
  106. The effect of selected substances on the stability of standard solutions in voltammetric analysis of ascorbic acid in fruit juices
  107. Determination of the content of Pb, Cd, Cu, Zn in dairy products from various regions of Poland
  108. Special Issue on IC3PE 2018 Conference
  109. The Photocatalytic Activity of Zns-TiO2 on a Carbon Fiber Prepared by Chemical Bath Deposition
  110. N-octyl chitosan derivatives as amphiphilic carrier agents for herbicide formulations
  111. Kinetics and Mechanistic Study of Hydrolysis of Adenosine Monophosphate Disodium Salt (AMPNa2) in Acidic and Alkaline Media
  112. Antimalarial Activity of Andrographis Paniculata Ness‘s N-hexane Extract and Its Major Compounds
  113. Special Issue on ABB2018 Conference
  114. Special Issue on ICCESEN 2017
  115. Theoretical Diagnostics of Second and Third-order Hyperpolarizabilities of Several Acid Derivatives
  116. Determination of Gamma Rays Efficiency Against Rhizoctonia solani in Potatoes
  117. Studies On Compatibilization Of Recycled Polyethylene/Thermoplastic Starch Blends By Using Different Compatibilizer
  118. Liquid−Liquid Extraction of Linalool from Methyl Eugenol with 1-Ethyl-3-methylimidazolium Hydrogen Sulfate [EMIM][HSO4] Ionic Liquid
  119. Synthesis of Graphene Oxide Through Ultrasonic Assisted Electrochemical Exfoliation
  120. Special Issue on ISCMP 2018
  121. Synthesis and antiproliferative evaluation of some 1,4-naphthoquinone derivatives against human cervical cancer cells
  122. The influence of the grafted aryl groups on the solvation properties of the graphyne and graphdiyne - a MD study
  123. Electrochemical modification of platinum and glassy carbon surfaces with pyridine layers and their use as complexing agents for copper (II) ions
  124. Effect of Electrospinning Process on Total Antioxidant Activity of Electrospun Nanofibers Containing Grape Seed Extract
  125. Effect Of Thermal Treatment Of Trepel At Temperature Range 800-1200˚C
  126. Topical Issue on Agriculture
  127. The effect of Cladophora glomerata exudates on the amino acid composition of Cladophora fracta and Rhizoclonium sp.
  128. Influence of the Static Magnetic Field and Algal Extract on the Germination of Soybean Seeds
  129. The use of UV-induced fluorescence for the assessment of homogeneity of granular mixtures
  130. The use of microorganisms as bio-fertilizers in the cultivation of white lupine
  131. Lyophilized apples on flax oil and ethyl esters of flax oil - stability and antioxidant evaluation
  132. Production of phosphorus biofertilizer based on the renewable materials in large laboratory scale
  133. Human health risk assessment of potential toxic elements in paddy soil and rice (Oryza sativa) from Ugbawka fields, Enugu, Nigeria
  134. Recovery of phosphates(V) from wastewaters of different chemical composition
  135. Special Issue on the 4th Green Chemistry 2018
  136. Dead zone for hydrogenation of propylene reaction carried out on commercial catalyst pellets
  137. Improved thermally stable oligoetherols from 6-aminouracil, ethylene carbonate and boric acid
  138. The role of a chemical loop in removal of hazardous contaminants from coke oven wastewater during its treatment
  139. Combating paraben pollution in surface waters with a variety of photocatalyzed systems: Looking for the most efficient technology
  140. Special Issue on Chemistry Today for Tomorrow 2019
  141. Applying Discriminant and Cluster Analyses to Separate Allergenic from Non-allergenic Proteins
  142. Chemometric Expertise Of Clinical Monitoring Data Of Prolactinoma Patients
  143. Chemomertic Risk Assessment of Soil Pollution
  144. New composite sorbent for speciation analysis of soluble chromium in textiles
  145. Photocatalytic activity of NiFe2O4 and Zn0.5Ni0.5Fe2O4 modified by Eu(III) and Tb(III) for decomposition of Malachite Green
  146. Photophysical and antibacterial activity of light-activated quaternary eosin Y
  147. Spectral properties and biological activity of La(III) and Nd(III) Monensinates
  148. Special Issue on Monitoring, Risk Assessment and Sustainable Management for the Exposure to Environmental Toxins
  149. Soil organic carbon mineralization in relation to microbial dynamics in subtropical red soils dominated by differently sized aggregates
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  175. Erratum
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