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Studies on the flammability of polypropylene/ammonium polyphosphate and montmorillonite by using the cone calorimeter test

  • A.A. Hanna EMAIL logo , M.A. Nour , E.R. Souaya , M.A. sherief and A.S. Abdelmoaty
Published/Copyright: March 2, 2018
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Open Chemistry
From the journal Open Chemistry Volume 16 Issue 1

Abstract

Fire performance of polypropylene (PP) containing different percentages of ammonium polyphosphate (APP) with montmorillonite (Mt) or treated montmorillonite (MtT) was carried out by using the cone calorimeter test (CCT). Different samples from ammonium polyphosphate and montmorillonite were mixed with 90% polypropylene. The characterization of the prepared samples indicates that there is incorporation between the components of the samples. Heat release rate (HRR), peak heat release rate (PHRR), average heat release rate (Av-HRR), and time to ignition (TTI) of the samples were obtained from the cone calorimeter test. Also, the fire performance index (FPI) and the fire growth rate (FIGRA) were calculated. The interpretation of the curves and the parameters results from the cone calorimeter test which indicates that the addition of montmorillonite to APP increases its action as a flame retardant for PP. Moreover, the samples contain acid treatment montmorillonite showed an increase in the efficiency of ammonium polyphosphate when used. This result may be due to an increase in the SiO2 content by acid treatment.

Graphical Abstract

Keywords: Flame retardant; montmorillonite; cone calorimeter test; thermal analysis; flammability; acid treatment

1 Introduction

Polypropylene (PP) is used in many industrial applications, such as automotives, furniture, electronic casings, indoor building decorates, and architectural materials as it is an environmentally friendly polymer [1,2].

Because PP consists chemically of carbon and hydrogen, it is easily ignited producing carbon dioxide and water vapor. The main drawback of using PP in special applications is its flammability; therefore, flame retardancy is an important requirement for PP [3]. The current literature survey indicates that there are general classes of flame retardants available today. There are the normal additions which are not chemically bonded to the polymer, and the reactive additives that are bonded to the polymer backbone through polymerization [4]. Different materials were used as flame retardants for the different polymers and the natural cellulosic materials such as wood and cotton. These materials includedorganic, inorganic and organic-inorganic substances. Also, they included some ores such as clays [5], zeolite [6]. In recent years [7,8,9,10,11] polymer/layered silicates nano-composites have attracted great interest, both in industries and academia. Montmorillonite (Mt) is commonly used as a nano-filler in the preparation of polymer nano-composites. Montmorillonite, and other layered silicate clays are naturally hydrophilic. This makes them poorly suited to mixing and interacting with most polymer matrices which are mostly hydrophobic. Moreover, the stacks of clay platelets are held tightly together by electrostatic forces. For these reasons, the clay must be treated before being used as a nano-composite. Between 2013-2017, Bettina and his co-workers focused their research on the formation of inttumescent flame retardants including ammonium polyphosphate (APP) and the different shapes of nano-particles of graphene [12,13,14,15,16]. They concluded that the presence of both APP and graphene improves the flammability of PP.

The efficiency of the flame retardant behavior of materials depends on the nature of the used materials as well as the conditions of the incorporation of the flame retardant materials into the polymer. To benefit the uses of PP in different applications, several paths were followed. First, modify the used materials, second related with how the flame retardant materials incorporated into the polymer and lastly related with the methods of the evaluation. In our previous work, ammonium polyphosphate (APP) was prepared in nanosized particles to increase the surface area of particles [17]. Also, it was used as flame retardant for PP [18]. The evaluation results indicated that the APP could be used as a flame retardant for PP when mixed up to 10% of the APP without any remarkable changes in the mechanical properties. Hanna et al [19] showed that the efficiency of APP as a flame retardant can be increased by adding some clays materials such as kaolin and diatomite. They found that the addition of kaolin or diatomite to APP with 6% benefits the uses of APP where the results indicated that the time of ignition increased from 14 to 28 sec. Furthermore, they modified the clay materials before mixing them with APP, and they observed that the acid treatment of clays increased their action [20].

There are different methods for evaluation of the flame retardant of materials such as thermogravimetric analysis (TGA), limiting oxygen index (LOI) and cone calorimeter test (CCT). Among these methods, the cone calorimeter test is a largely accepted method for evaluation because this test gives different parameters such as heat release rate (HRR), average heat release rate (Av.HRR) total heat release (THR) and time to ignition (TTI) [21]. The interpretation of these parameters gives complete information about the behavior on the burning of the materials and could evaluate the system successfully [22].

The thermal decomposition (TGA and DTA) of the composite was studied previously [23] under the same composition. The results indicated that the addition of APP+ montmorillonite improves the thermal stability and increases the time of degradation.

To benefit natural montmorollonite (Mt) which is more abundant in Egypt, the present work aimed to study the effects of the addition of different amounts of montmorillonite (Mt) to APP (10%) relating to the flammability of PP and by applying the cone calorimeter test. Furthermore, an acid treatment on Mt was carried out to study the effects of this treatment on the efficiency of APP/Mt when used as a flame retardant for PP.

2 Experimental

2.1 Materials

2.1.1 Ammonium polyphosphate (APP)

Ammonium polyphosphate was prepared from ammonium dihydrogen phosphate and ammonia solution as described elsewhere [17]. The characterization of the produced APP indicated that the product has a particle size between 5 to 85 nm and is typical to form I of APP.

2.1.2 Polypropylene (PP)

Polypropylene (PP) has a chemical formula (CH2=CH-CH3), according to IUPAC nomenclature, its molecular formula is (C3H6)n, its density is in the range of 0.855 to 0.946 gm.cm-3 for the amorphous or the crystalline form. It melts at about 130-171oC, (LG Chem, Ltd Seetc, N1600 B001046M, Korea).

2.1.3 Montmorillonite (Mt)

In this study, montmorillonite was supplied by the geology department of the National Research Center, which was derived from Wadi El Hamadiya region, Egypt. The sample was used without further treatment. The untreated montmorillonite, contains SiO2=42.02, Al2O3=4707, Mgo=0.028, CaO=0.035, K2O=0.013, ZnO=0.006, TiO2=0.76 and Fe2O3=0.005 wt%. Furthermore, the montmorillonite was exposed to H2SO4 treatment to increase the surface area. This treatment did not affect the mechanism of the flammability, but changed the structure and the orientation of the montmorillonite. The treated montmorillonite, contains SiO2=55.32, Al2O3=28.88, MgO=0.021, CaO=0.013, K2O=0.011, ZnO=0.006, TiO2=0.25 and Fe2O3=0.004 wt% (10). It is noteworthy that the Mt analysis was carried out by XRF weight % as mentioned in the previous work.

2.2 Preparation of the samples

Different percentages of APP and unmodified montmorillonite (Mt) or modified montmorillonite (MtT) were prepared by a melt blending method using a newplast twin screw extruder (India) at a temperature of 185-190°C. The twin screw speed was 30 rpm. The samples obtained from the extruder were preheated using a Morgan press injection unit at a temperature of 190-195°C to produce 7.5 x7.5 x 0.4 cm molds. The samples codes and preparation conditions are listed in Table 1.

Table 1

The samples codes and preparation conditions of the samples.

Treated montmorillonite (MtT) %Montmorillonite (Mt)%APP %PP %Sample code
000100PP
001090APP10%
02890Mt2
04690Mt4
06490Mt6
08290Mt8
010090Mt10
20890MtT2
40690MtT4
60490MtT6
80290MtT8
100090MtT10

2.3 Measurements

FTIR spectra of the samples were obtained using a KBr disk technique and FTIR 6500 spectrometer (JASCO, Japan) in the range of 400-4000cm-1. The surface morphologies of the samples were carried out using a JEOL JSM t20 scanning electron microscope (SEM) (JEOL, Japan) at an accelerating voltage of 5 kV. A cone calorimeter test was performed using fire testing technology Ltd equipment according to ASTM 1354-95. Samples, with dimensions of 7.5 x 7.5 x 0.4 mm3, were tested horizontally under an incident flux of 35 kW/m2. The cone calorimeter that was attached to a software program modified automatically to the standard dimensions 10*10*0.5 (22)

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

3 Results and Discussion

3.1 FTIR measurements

The IR measurements of PP and APP10% samples are shown in Figure 1. The IR spectra show that different peaks appeared as follows:

Figure 1 FTIR for PP and APP10%.
Figure 1

FTIR for PP and APP10%.

  1. Absorption bands appeared at 3087, 2922, 1457, 1378 and 890 cm-1. These bands may correspond to the C-H bond of the saturated and unsaturated part of the PP chain [23,24].

  2. Specific characteristics of the P-O and P=O attached into APP appeared at 1117, 1081 and 1079 cm-1.

  3. Important series of bands at 1158, 1000, 927 and 492 cm-1 corresponding to the P-O and P-O-P indicate that there was an interaction between the PP and APP.

The FTIR absorption spectra of (Mt2, Mt 4, Mt 6, Mt 8 and Mt 10) and (MtT 2, MtT 4, MtT 6, MtT 8 and MtT 10) show new bands at 1165, 990, 931, cm-1 which are assignable to (Si-O-P), (Si-O-C) and (SiOH) respectively. This result confirms that there was an interaction between the montmorillonite (treated or untreated) with PP and APP as shown in Figures 2 and 3. This interaction may be due to two factors. The first factor relates to an electrostatic force between the montmorillonite and the surface of PP; the second factor penetrates the montmorillonite particles between the layers of PP.

Figure 2 FTIR for Mt2, Mt4, Mt6, Mt8 and Mt10.
Figure 2

FTIR for Mt2, Mt4, Mt6, Mt8 and Mt10.

Figure 3 FTIR for MtT2, MtT4, MtT6, MtT8 and MtT10.
Figure 3

FTIR for MtT2, MtT4, MtT6, MtT8 and MtT10.

3.2 Scanning electron microscope (SEM)

The morphology of PP, PP/APP, PP/APP+ montmorillonite or treated montmorillonite was studied, and the photos were shown in Figures 4, 5 and 6. The photo shows that the particles of PP were distributed uniformly, whereby adding 10% APP, the texture converted to layers. For the samples which contained montmorillonite or modified montmorillonite, the layer structure increased as eviudencedin Figures 5 and 6. It is observed that as the percentage of montmorillonite or modified montmorillonite increased, the clearance and the layers formation were enhanced.

Figure 4 SEM of a) PP and b) PP/10%APP. (The magnification equal 3000).
Figure 4

SEM of a) PP and b) PP/10%APP. (The magnification equal 3000).

Figure 5 SEM of a)Mt2, b) Mt4, c)Mt6, d)Mt8 and e)Mt10. (The magnification equal 3000).
Figure 5

SEM of a)Mt2, b) Mt4, c)Mt6, d)Mt8 and e)Mt10. (The magnification equal 3000).

Figure 6 SEM of a)MtT2, b) MtT4, c)MtT6, d)MtT8 and e)MtT10. (The magnification equal 3000).
Figure 6

SEM of a)MtT2, b) MtT4, c)MtT6, d)MtT8 and e)MtT10. (The magnification equal 3000).

3.3 Cone calorimeter test

The cone calorimeter test was used to evaluate the flammability of the samples under investigation. This test represents a small scale testing configuration which provides important correlating parameters with a real fire scenario and gives different parameters. The heat release rate (HRR), the peak of the heat release rate (PHRRP) and the average heat release rate (Av-HRR) are quantitative measures of thermal energy released by a materialper unit area when exposed to a fire radiating at a constant heat flux (or temperature) usually at 35 kW/m2. The time to ignition (TTI) corresponds to the period that combustible materials can withstand when exposed to a constant radiant heat flux before ignition and when undergoing sustained flaming combustion. The cone calorimeter data reported in Table 2 represent an average of the three replicate experiments.

Table 2

Main cone calorimeter parameters evaluated of the samples.

FPI (sm2/kW)THR (MJ/m2)FIGRA (kW/m2s)AV. HRR (KW/m2)PHRR (KW/m2) %TTI (S)Samples
0.0126810613.8447110414PP
0.02595928.833492524APP10%
(16.2%)
0.03251668.0923276925Mt2
(30.34)
0.03529657.2522876527Mt4
(30.79)
0.03665647.2022676428Mt6
(30.70)
0.03862627.1722175129Mt8
(31.97)
0.017919913.08359100518Mt10
(8.97)
0.04056645.9121471529MtT2
(35.23)
0.04846635.8021261930MtT4
(43.93)
0.05003576.0721159930MtT6
(45.74)
0.05391565.3814857531MtT8
47.91
0.020549812.0935292519MtT10
(16.21)

The HRR value is considered to be the single most important fire reaction property as it represents the most valuable indicator of the fire hazard for combustible materials.

The variation of the heat release rate (HRR) followed the same trends, while its value increased with time and formed peaks and decreased to obtain the steady state at about 180 seconds as shown in Figure 7. The peak of the heat release rate equals 1104 KW/m2 for the PP sample without any addition. By adding 10% APP to PP, the value of PHRR reduced to 925 KW/m2 (16.2% reduction) as shown in Table 2. For the samples containing APP with Mt (Mt2, Mt4, Mt6, Mt8), the values of PHRR equaled 769, 765, 764 and 751 KW/m2 respectively. This means that the values of reduction continue for the Mt2 reaching a nearly steady state for the other samples. For sample Mt10 which contained 10% Mt and free APP, the value of PHRR was equal to 1005 KW/m2. This finding indicates that the mixture of APP with Mt is more effective than using APP that is free of Mt or, Mt free of APP. This may be explained by the mutual effects between APP and Mt where the presence of low Mt accelerated the degradation of APP, while the increase in the percentage of Mt decreased the degradation of APP due to the coating effect.

Figure 7 HRR of PP and APP10% and Mt2, Mt4, Mt6, Mt8, Mt10.
Figure 7

HRR of PP and APP10% and Mt2, Mt4, Mt6, Mt8, Mt10.

For the cone calorimeter test, the data shown in Figures 7, 8 and Table 2. For the samples containing MtT, it was observed that the reduction in the values of PHRR was greater than that obtained for the samples containing Mt.

Figure 8 HRR of PP and APP10% and MtT2, MtT4, MtT6, MtT8, MtT10.
Figure 8

HRR of PP and APP10% and MtT2, MtT4, MtT6, MtT8, MtT10.

Contrary, the average heat release rate (Av-HRR) Table 2 exhibits the same trend as that observed for PHRR, where the values of Av-HRR decreased from 447 to 221 KW/ m2. The reducing value for the sample Mt8 was higher than the other samples. This finding confirmed the behavior of PHRR. For samples containing MtT, the curves and the parameters of the cone calorimeter test showed that:

  1. There was a reduction in the values of PHRR for all samples

  2. This reduction was larger than that obtained for the samples containing untreated Mt, where it recorded a reduction 35.23, 43.93, 45.70 and 47.91 KW/m2 for the samples MtT2, MtT4, MtT6 and MtT8 respectively.

  3. The average HRR for the samples from MtT2 to MtT8 decreased gradually as the percentage of treated Mt (MtT) increased with a recording of 148 KW/m2 for sample MtT8.

As reported previously, PHRR is a measure of the progress of burning and the observation of the average HRR. It may be concluded that the addition of Mt to APP inhibits the spread of the fire due to the thermal decomposition of APP to produce nitrogen and phosphorus acid and the effect of the samples free of APP is minimal.

Ignition data are reported as time to substance ignition, which is defined as ignition with the assistance of a spark igniter. The time to ignition for all samples (APP10%, Mt2, Mt4, Mt6, Mt8, Mt10, MtT2, MtT4, MtT6, MtT8 and MtT10) is higher than that for the pure PP sample. These results are in agreement with the data obtained from PHRR values.

The fire growth rate (FIGRA), computed as PHRR/time to PHRR, provides the basis for estimation of both the predicted fire spread rate and the size of fire [21] and is a good indicator of the contribution to fire growth of materials. The FIGRA for all samples is shown in Table 2. The values of FIGRA were decreased from 13.8 to 8.8 for PP without any addition for the sample containing 10% of APP, while it decreased to 8.09 for the Mt2 sample. These decreases continue as the amount of Mt increases with a recording value equal to 7.17 for the Mt8 sample. As a comparison, the recorded value for the sample Mt10 was 13.08. This indicates that the mixture of APP and montmorillonite is more effective as a flame retardant. In all cases the samples which contained treated montmorillonite (MtT2, MtT4, MtT6, MtT8, MtT10), showed lower FIGRA valuesthan those for untreated montmorillonite. Also, the results indicate that the treatment of montmorillonite improved the action of montmorillonite when used with APP as a flame retardant material for PP.

Another important parameter is the the fire performance index (FPI) that was calculated as the ratio between the time to ignition (TTI) and the peak of heat release (PHRR):

FPI=TTI/PHRR

This FPI value gives useful information about the degree of fire hazard [25,26,27,28,29]. The calculated values of FPI for all samples as shown in Table 2 are increased by adding APP or APP+ montmorillonite or treated montmorillonite. This indicates that the presence of montmorillonite increased this APP efficiency when used as a flame retardant for PP; however, this efficiency increased by the treatment of montmorillonite.

The values of THR for the samples are represented graphically in Figures 9 and Figure 10 for all samples (APP10%, Mt2, Mt4, Mt6, Mt8, Mt10, MtT2, MtT4, MtT6, MtT8 and MtT10) shows a lower value (92, 66,65, 64, 62, 99, 64, 63, 57, 56 and 98, respectively), in comparison to pure PP(106 KJ/m2). It is very interesting that the value of the total heat release was decreased for all samples compared to pure PP.

Figure 9 Total heat release of (PP, APP10% Mt2, Mt4, Mt6, Mt8, Mt10) samples.
Figure 9

Total heat release of (PP, APP10% Mt2, Mt4, Mt6, Mt8, Mt10) samples.

Figure 10 Total heat release of (PP, APP10% MtT2, MtT 4, MtT 6, MtT 8, MtT 10) samples.
Figure 10

Total heat release of (PP, APP10% MtT2, MtT 4, MtT 6, MtT 8, MtT 10) samples.

4 Conclusion

Results conclude that the addition of montmorillonite to APP increases the effects of APP when used as a flame retardant of PP. On the other hand, the treatment of montmorillonite with H2SO4 raised the action of montmorillonite when added to APP. This may be due to the increase in the SiO2 content as well as the high surface area resulting in acid treatment of montmorillonite.

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

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Received: 2017-08-17
Accepted: 2018-01-11
Published Online: 2018-03-02

© 2018 A.A. Hanna et al., published by De Gruyter

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

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  16. Experimental study on the regulation of the cholinergic pathway in renal macrophages by microRNA-132 to alleviate inflammatory response
  17. Synthesis, characterization, in-vitro antimicrobial properties, molecular docking and DFT studies of 3-{(E)-[(4,6-dimethylpyrimidin-2-yl)imino]methyl} naphthalen-2-ol and Heteroleptic Mn(II), Co(II), Ni(II) and Zn(II) complexes
  18. M-Polynomials and Topological Indices of Dominating David Derived Networks
  19. Human Health Risk Assessment of Trace Metals in Surface Water Due to Leachate from the Municipal Dumpsite by Pollution Index: A Case Study from Ndawuse River, Abuja, Nigeria
  20. Analysis of Bowel Diseases from Blood Serum by Autofluorescence and Atomic Force Microscopy Techniques
  21. Hydrographic parameters and distribution of dissolved Cu, Ni, Zn and nutrients near Jeddah desalination plant
  22. Relationships between diatoms and environmental variables in industrial water biotopes of Trzuskawica S.A. (Poland)
  23. Optimum Conversion of Major Ginsenoside Rb1 to Minor Ginsenoside Rg3(S) by Pulsed Electric Field-Assisted Acid Hydrolysis Treatment
  24. Antioxidant, Anti-microbial Properties and Chemical Composition of Cumin Essential Oils Extracted by Three Methods
  25. Regulatory mechanism of ulinastatin on autophagy of macrophages and renal tubular epithelial cells
  26. Investigation of the sustained-release mechanism of hydroxypropyl methyl cellulose skeleton type Acipimox tablets
  27. Bio-accumulation of Polycyclic Aromatic Hydrocarbons in the Grey Mangrove (Avicennia marina) along Arabian Gulf, Saudi Coast
  28. Dynamic Change of Secondary Metabolites and spectrum-effect relationship of Malus halliana Koehne flowers during blooming
  29. Lipids constituents from Gardenia aqualla Stapf & Hutch
  30. Effect of using microwaves for catalysts preparation on the catalytic acetalization of glycerol with furfural to obtain fuel additives
  31. Effect of Humic Acid on the Degradation of Methylene Blue by Peroxymonosulfate
  32. Serum containing drugs of Gua Lou Xie Bai decoction (GLXB-D) can inhibit TGF-β1-Induced Epithelial to Mesenchymal Transition (EMT) in A549 Cells
  33. Antiulcer Activity of Different Extracts of Anvillea garcinii and Isolation of Two New Secondary Metabolites
  34. Analysis of Metabolites in Cabernet Sauvignon and Shiraz Dry Red Wines from Shanxi by 1H NMR Spectroscopy Combined with Pattern Recognition Analysis
  35. Can water temperature impact litter decomposition under pollution of copper and zinc mixture
  36. Released from ZrO2/SiO2 coating resveratrol inhibits senescence and oxidative stress of human adipose-derived stem cells (ASC)
  37. Validated thin-layer chromatographic method for alternative and simultaneous determination of two anti-gout agents in their fixed dose combinations
  38. Fast removal of pollutants from vehicle emissions during cold-start stage
  39. Review Article
  40. Catalytic activities of heterogeneous catalysts obtained by copolymerization of metal-containing 2-(acetoacetoxy)ethyl methacrylate
  41. Antibiotic Residue in the Aquatic Environment: Status in Africa
  42. Regular Articles
  43. Mercury fractionation in gypsum using temperature desorption and mass spectrometric detection
  44. Phytosynthetic Ag doped ZnO nanoparticles: Semiconducting green remediators
  45. Epithelial–Mesenchymal Transition Induced by SMAD4 Activation in Invasive Growth Hormone-Secreting Adenomas
  46. Physicochemical properties of stabilized sewage sludge admixtures by modified steel slag
  47. In Vitro Cytotoxic and Antiproliferative Activity of Cydonia oblonga flower petals, leaf and fruit pellet ethanolic extracts. Docking simulation of the active flavonoids on anti-apoptotic protein Bcl-2
  48. Synthesis and Characterization of Pd exchanged MMT Clay for Mizoroki-Heck Reaction
  49. A new selective, and sensitive method for the determination of lixivaptan, a vasopressin 2 (V2)-receptor antagonist, in mouse plasma and its application in a pharmacokinetic study
  50. Anti-EGFL7 antibodies inhibit rat prolactinoma MMQ cells proliferation and PRL secretion
  51. Density functional theory calculations, vibration spectral analysis and molecular docking of the antimicrobial agent 6-(1,3-benzodioxol-5-ylmethyl)-5-ethyl-2-{[2-(morpholin-4-yl)ethyl] sulfanyl}pyrimidin-4(3H)-one
  52. Effect of Nano Zeolite on the Transformation of Cadmium Speciation and Its Uptake by Tobacco in Cadmium-contaminated Soil
  53. Effects and Mechanisms of Jinniu Capsule on Methamphetamine-Induced Conditioned Place Preference in Rats
  54. Calculating the Degree-based Topological Indices of Dendrimers
  55. Efficient optimization and mineralization of UV absorbers: A comparative investigation with Fenton and UV/H2O2
  56. Metabolites of Tryptophane and Phenylalanine as Markers of Small Bowel Ischemia-Reperfusion Injury
  57. Adsorption and determination of polycyclic aromatic hydrocarbons in water through the aggregation of graphene oxide
  58. The role of NR2C2 in the prolactinomas
  59. Chromium removal from industrial wastewater using Phyllostachys pubescens biomass loaded Cu-S nanospheres
  60. Hydrotalcite Anchored Ruthenium Catalyst for CO2 Hydrogenation Reaction
  61. Preparation of Calcium Fluoride using Phosphogypsum by Orthogonal Experiment
  62. The mechanism of antibacterial activity of corylifolinin against three clinical bacteria from Psoralen corylifolia L
  63. 2-formyl-3,6-bis(hydroxymethyl)phenyl benzoate in Electrochemical Dry Cell
  64. Electro-photocatalytic degradation of amoxicillin using calcium titanate
  65. Effect of Malus halliana Koehne Polysaccharides on Functional Constipation
  66. Structural Properties and Nonlinear Optical Responses of Halogenated Compounds: A DFT Investigation on Molecular Modelling
  67. DMFDMA catalyzed synthesis of 2-((Dimethylamino)methylene)-3,4-dihydro-9-arylacridin-1(2H)-ones and their derivatives: in-vitro antifungal, antibacterial and antioxidant evaluations
  68. Production of Methanol as a Fuel Energy from CO2 Present in Polluted Seawater - A Photocatalytic Outlook
  69. Study of different extraction methods on finger print and fatty acid of raw beef fat using fourier transform infrared and gas chromatography-mass spectrometry
  70. Determination of trace fluoroquinolones in water solutions and in medicinal preparations by conventional and synchronous fluorescence spectrometry
  71. Extraction and determination of flavonoids in Carthamus tinctorius
  72. Therapeutic Application of Zinc and Vanadium Complexes against Diabetes Mellitus a Coronary Disease: A review
  73. Study of calcined eggshell as potential catalyst for biodiesel formation using used cooking oil
  74. Manganese oxalates - structure-based Insights
  75. Topological Indices of H-Naphtalenic Nanosheet
  76. Long-Term Dissolution of Glass Fibers in Water Described by Dissolving Cylinder Zero-Order Kinetic Model: Mass Loss and Radius Reduction
  77. Topological study of the para-line graphs of certain pentacene via topological indices
  78. A brief insight into the prediction of water vapor transmissibility in highly impermeable hybrid nanocomposites based on bromobutyl/epichlorohydrin rubber blends
  79. Comparative sulfite assay by voltammetry using Pt electrodes, photometry and titrimetry: Application to cider, vinegar and sugar analysis
  80. MicroRNA delivery mediated by PEGylated polyethylenimine for prostate cancer therapy
  81. Reversible Fluorescent Turn-on Sensors for Fe3+ based on a Receptor Composed of Tri-oxygen Atoms of Amide Groups in Water
  82. Sonocatalytic degradation of methyl orange in aqueous solution using Fe-doped TiO2 nanoparticles under mechanical agitation
  83. Hydrotalcite Anchored Ruthenium Catalyst for CO2 Hydrogenation Reaction
  84. Production and Analysis of Recycled Ammonium Perrhenate from CMSX-4 superalloys
  85. Topical Issue on Agriculture
  86. New phosphorus biofertilizers from renewable raw materials in the aspect of cadmium and lead contents in soil and plants
  87. Survey of content of cadmium, calcium, chromium, copper, iron, lead, magnesium, manganese, mercury, sodium and zinc in chamomile and green tea leaves by electrothermal or flame atomizer atomic absorption spectrometry
  88. Biogas digestate – benefits and risks for soil fertility and crop quality – an evaluation of grain maize response
  89. A numerical analysis of heat transfer in a cross-current heat exchanger with controlled and newly designed air flows
  90. Freshwater green macroalgae as a biosorbent of Cr(III) ions
  91. The main influencing factors of soil mechanical characteristics of the gravity erosion environment in the dry-hot valley of Jinsha river
  92. Free amino acids in Viola tricolor in relation to different habitat conditions
  93. The influence of filler amount on selected properties of new experimental resin dental composite
  94. Effect of poultry wastewater irrigation on nitrogen, phosphorus and carbon contents in farmland soil
  95. Response of spring wheat to NPK and S fertilization. The content and uptake of macronutrients and the value of ionic ratios
  96. The Effect of Macroalgal Extracts and Near Infrared Radiation on Germination of Soybean Seedlings: Preliminary Research Results
  97. Content of Zn, Cd and Pb in purple moor-grass in soils heavily contaminated with heavy metals around a zinc and lead ore tailing landfill
  98. Topical Issue on Research for Natural Bioactive Products
  99. Synthesis of (±)-3,4-dimethoxybenzyl-4-methyloctanoate as a novel internal standard for capsinoid determination by HPLC-ESI-MS/MS(QTOF)
  100. Repellent activity of monoterpenoid esters with neurotransmitter amino acids against yellow fever mosquito, Aedes aegypti
  101. Effect of Flammulina velutipes (golden needle mushroom, eno-kitake) polysaccharides on constipation
  102. Bioassay-directed fractionation of a blood coagulation factor Xa inhibitor, betulinic acid from Lycopus lucidus
  103. Antifungal and repellent activities of the essential oils from three aromatic herbs from western Himalaya
  104. Chemical composition and microbiological evaluation of essential oil from Hyssopus officinalis L. with white and pink flowers
  105. Bioassay-guided isolation and identification of Aedes aegypti larvicidal and biting deterrent compounds from Veratrum lobelianum
  106. α-Terpineol, a natural monoterpene: A review of its biological properties
  107. Utility of essential oils for development of host-based lures for Xyleborus glabratus (Coleoptera: Curculionidae: Scolytinae), vector of laurel wilt
  108. Phenolic composition and antioxidant potential of different organs of Kazakh Crataegus almaatensis Pojark: A comparison with the European Crataegus oxyacantha L. flowers
  109. Isolation of eudesmane type sesquiterpene ketone from Prangos heyniae H.Duman & M.F.Watson essential oil and mosquitocidal activity of the essential oils
  110. Comparative analysis of the polyphenols profiles and the antioxidant and cytotoxicity properties of various blue honeysuckle varieties
  111. Special Issue on ICCESEN 2017
  112. Modelling world energy security data from multinomial distribution by generalized linear model under different cumulative link functions
  113. Pine Cone and Boron Compounds Effect as Reinforcement on Mechanical and Flammability Properties of Polyester Composites
  114. Artificial Neural Network Modelling for Prediction of SNR Effected by Probe Properties on Ultrasonic Inspection of Austenitic Stainless Steel Weldments
  115. Calculation and 3D analyses of ERR in the band crack front contained in a rectangular plate made of multilayered material
  116. Improvement of fuel properties of biodiesel with bioadditive ethyl levulinate
  117. Properties of AlSi9Cu3 metal matrix micro and nano composites produced via stir casting
  118. Investigation of Antibacterial Properties of Ag Doped TiO2 Nanofibers Prepared by Electrospinning Process
  119. Modeling of Total Phenolic contents in Various Tea samples by Experimental Design Methods
  120. Nickel doping effect on the structural and optical properties of indium sulfide thin films by SILAR
  121. The effect mechanism of Ginnalin A as a homeopathic agent on various cancer cell lines
  122. Excitation functions of proton induced reactions of some radioisotopes used in medicine
  123. Oxide ionic conductivity and microstructures of Pr and Sm co-doped CeO2-based systems
  124. Rapid Synthesis of Metallic Reinforced in Situ Intermetallic Composites in Ti-Al-Nb System via Resistive Sintering
  125. Oxidation Behavior of NiCr/YSZ Thermal Barrier Coatings (TBCs)
  126. Clustering Analysis of Normal Strength Concretes Produced with Different Aggregate Types
  127. Magnetic Nano-Sized Solid Acid Catalyst Bearing Sulfonic Acid Groups for Biodiesel Synthesis
  128. The biological activities of Arabis alpina L. subsp. brevifolia (DC.) Cullen against food pathogens
  129. Humidity properties of Schiff base polymers
  130. Free Vibration Analysis of Fiber Metal Laminated Straight Beam
  131. Comparative study of in vitro antioxidant, acetylcholinesterase and butyrylcholinesterase activity of alfalfa (Medicago sativa L.) collected during different growth stages
  132. Isothermal Oxidation Behavior of Gadolinium Zirconate (Gd2Zr2O7) Thermal Barrier Coatings (TBCs) produced by Electron Beam Physical Vapor Deposition (EB-PVD) technique
  133. Optimization of Adsorption Parameters for Ultra-Fine Calcite Using a Box-Behnken Experimental Design
  134. The Microstructural Investigation of Vermiculite-Infiltrated Electron Beam Physical Vapor Deposition Thermal Barrier Coatings
  135. Modelling Porosity Permeability of Ceramic Tiles using Fuzzy Taguchi Method
  136. Experimental and theoretical study of a novel naphthoquinone Schiff base
  137. Physicochemical properties of heat treated sille stone for ceramic industry
  138. Sand Dune Characterization for Preparing Metallurgical Grade Silicon
  139. Catalytic Applications of Large Pore Sulfonic Acid-Functionalized SBA-15 Mesoporous Silica for Esterification
  140. One-photon Absorption Characterizations, Dipole Polarizabilities and Second Hyperpolarizabilities of Chlorophyll a and Crocin
  141. The Optical and Crystallite Characterization of Bilayer TiO2 Films Coated on Different ITO layers
  142. Topical Issue on Bond Activation
  143. Metal-mediated reactions towards the synthesis of a novel deaminolysed bisurea, dicarbamolyamine
  144. The structure of ortho-(trifluoromethyl)phenol in comparison to its homologues – A combined experimental and theoretical study
  145. Heterogeneous catalysis with encapsulated haem and other synthetic porphyrins: Harnessing the power of porphyrins for oxidation reactions
  146. Recent Advances on Mechanistic Studies on C–H Activation Catalyzed by Base Metals
  147. Reactions of the organoplatinum complex [Pt(cod) (neoSi)Cl] (neoSi = trimethylsilylmethyl) with the non-coordinating anions SbF6– and BPh4–
  148. Erratum
  149. Investigation on Two Compounds of O, O’-dithiophosphate Derivatives as Corrosion Inhibitors for Q235 Steel in Hydrochloric Acid Solution
https://doi.org/10.1515/chem-2018-0013
Keywords for this article
Flame retardant; montmorillonite; cone calorimeter test; thermal analysis; flammability; acid treatment
Creative Commons
BY-NC-ND 4.0

Articles in the same Issue

  1. Regular Articles
  2. The effect of CuO modification for a TiO2 nanotube confined CeO2 catalyst on the catalytic combustion of butane
  3. The preparation and antibacterial activity of cellulose/ZnO composite: a review
  4. Linde Type A and nano magnetite/NaA zeolites: cytotoxicity and doxorubicin loading efficiency
  5. Performance and thermal decomposition analysis of foaming agent NPL-10 for use in heavy oil recovery by steam injection
  6. Spectroscopic (FT-IR, FT-Raman, UV, 1H and 13C NMR) insights, electronic profiling and DFT computations on ({(E)-[3-(1H-imidazol-1-yl)-1-phenylpropylidene] amino}oxy)(4-nitrophenyl)methanone, an imidazole-bearing anti-Candida agent
  7. A Simplistic Preliminary Assessment of Ginstling-Brounstein Model for Solid Spherical Particles in the Context of a Diffusion-Controlled Synthesis
  8. M-Polynomials And Topological Indices Of Zigzag And Rhombic Benzenoid Systems
  9. Photochemical Transformation of some 3-benzyloxy-2-(benzo[b]thiophen-2-yl)-4Hchromen-4-ones: A Remote Substituent Effect
  10. Dynamic Changes of Secondary Metabolites and Antioxidant Activity of Ligustrum lucidum During Fruit Growth
  11. Studies on the flammability of polypropylene/ammonium polyphosphate and montmorillonite by using the cone calorimeter test
  12. DSC, FT-IR, NIR, NIR-PCA and NIR-ANOVA for determination of chemical stability of diuretic drugs: impact of excipients
  13. Antioxidant and Hepatoprotective Effects of Methanolic Extracts of Zilla spinosa and Hammada elegans Against Carbon Tetrachlorideinduced Hepatotoxicity in Rats
  14. Prunus cerasifera Ehrh. fabricated ZnO nano falcates and its photocatalytic and dose dependent in vitro bio-activity
  15. Organic biocides hosted in layered double hydroxides: enhancing antimicrobial activity
  16. Experimental study on the regulation of the cholinergic pathway in renal macrophages by microRNA-132 to alleviate inflammatory response
  17. Synthesis, characterization, in-vitro antimicrobial properties, molecular docking and DFT studies of 3-{(E)-[(4,6-dimethylpyrimidin-2-yl)imino]methyl} naphthalen-2-ol and Heteroleptic Mn(II), Co(II), Ni(II) and Zn(II) complexes
  18. M-Polynomials and Topological Indices of Dominating David Derived Networks
  19. Human Health Risk Assessment of Trace Metals in Surface Water Due to Leachate from the Municipal Dumpsite by Pollution Index: A Case Study from Ndawuse River, Abuja, Nigeria
  20. Analysis of Bowel Diseases from Blood Serum by Autofluorescence and Atomic Force Microscopy Techniques
  21. Hydrographic parameters and distribution of dissolved Cu, Ni, Zn and nutrients near Jeddah desalination plant
  22. Relationships between diatoms and environmental variables in industrial water biotopes of Trzuskawica S.A. (Poland)
  23. Optimum Conversion of Major Ginsenoside Rb1 to Minor Ginsenoside Rg3(S) by Pulsed Electric Field-Assisted Acid Hydrolysis Treatment
  24. Antioxidant, Anti-microbial Properties and Chemical Composition of Cumin Essential Oils Extracted by Three Methods
  25. Regulatory mechanism of ulinastatin on autophagy of macrophages and renal tubular epithelial cells
  26. Investigation of the sustained-release mechanism of hydroxypropyl methyl cellulose skeleton type Acipimox tablets
  27. Bio-accumulation of Polycyclic Aromatic Hydrocarbons in the Grey Mangrove (Avicennia marina) along Arabian Gulf, Saudi Coast
  28. Dynamic Change of Secondary Metabolites and spectrum-effect relationship of Malus halliana Koehne flowers during blooming
  29. Lipids constituents from Gardenia aqualla Stapf & Hutch
  30. Effect of using microwaves for catalysts preparation on the catalytic acetalization of glycerol with furfural to obtain fuel additives
  31. Effect of Humic Acid on the Degradation of Methylene Blue by Peroxymonosulfate
  32. Serum containing drugs of Gua Lou Xie Bai decoction (GLXB-D) can inhibit TGF-β1-Induced Epithelial to Mesenchymal Transition (EMT) in A549 Cells
  33. Antiulcer Activity of Different Extracts of Anvillea garcinii and Isolation of Two New Secondary Metabolites
  34. Analysis of Metabolites in Cabernet Sauvignon and Shiraz Dry Red Wines from Shanxi by 1H NMR Spectroscopy Combined with Pattern Recognition Analysis
  35. Can water temperature impact litter decomposition under pollution of copper and zinc mixture
  36. Released from ZrO2/SiO2 coating resveratrol inhibits senescence and oxidative stress of human adipose-derived stem cells (ASC)
  37. Validated thin-layer chromatographic method for alternative and simultaneous determination of two anti-gout agents in their fixed dose combinations
  38. Fast removal of pollutants from vehicle emissions during cold-start stage
  39. Review Article
  40. Catalytic activities of heterogeneous catalysts obtained by copolymerization of metal-containing 2-(acetoacetoxy)ethyl methacrylate
  41. Antibiotic Residue in the Aquatic Environment: Status in Africa
  42. Regular Articles
  43. Mercury fractionation in gypsum using temperature desorption and mass spectrometric detection
  44. Phytosynthetic Ag doped ZnO nanoparticles: Semiconducting green remediators
  45. Epithelial–Mesenchymal Transition Induced by SMAD4 Activation in Invasive Growth Hormone-Secreting Adenomas
  46. Physicochemical properties of stabilized sewage sludge admixtures by modified steel slag
  47. In Vitro Cytotoxic and Antiproliferative Activity of Cydonia oblonga flower petals, leaf and fruit pellet ethanolic extracts. Docking simulation of the active flavonoids on anti-apoptotic protein Bcl-2
  48. Synthesis and Characterization of Pd exchanged MMT Clay for Mizoroki-Heck Reaction
  49. A new selective, and sensitive method for the determination of lixivaptan, a vasopressin 2 (V2)-receptor antagonist, in mouse plasma and its application in a pharmacokinetic study
  50. Anti-EGFL7 antibodies inhibit rat prolactinoma MMQ cells proliferation and PRL secretion
  51. Density functional theory calculations, vibration spectral analysis and molecular docking of the antimicrobial agent 6-(1,3-benzodioxol-5-ylmethyl)-5-ethyl-2-{[2-(morpholin-4-yl)ethyl] sulfanyl}pyrimidin-4(3H)-one
  52. Effect of Nano Zeolite on the Transformation of Cadmium Speciation and Its Uptake by Tobacco in Cadmium-contaminated Soil
  53. Effects and Mechanisms of Jinniu Capsule on Methamphetamine-Induced Conditioned Place Preference in Rats
  54. Calculating the Degree-based Topological Indices of Dendrimers
  55. Efficient optimization and mineralization of UV absorbers: A comparative investigation with Fenton and UV/H2O2
  56. Metabolites of Tryptophane and Phenylalanine as Markers of Small Bowel Ischemia-Reperfusion Injury
  57. Adsorption and determination of polycyclic aromatic hydrocarbons in water through the aggregation of graphene oxide
  58. The role of NR2C2 in the prolactinomas
  59. Chromium removal from industrial wastewater using Phyllostachys pubescens biomass loaded Cu-S nanospheres
  60. Hydrotalcite Anchored Ruthenium Catalyst for CO2 Hydrogenation Reaction
  61. Preparation of Calcium Fluoride using Phosphogypsum by Orthogonal Experiment
  62. The mechanism of antibacterial activity of corylifolinin against three clinical bacteria from Psoralen corylifolia L
  63. 2-formyl-3,6-bis(hydroxymethyl)phenyl benzoate in Electrochemical Dry Cell
  64. Electro-photocatalytic degradation of amoxicillin using calcium titanate
  65. Effect of Malus halliana Koehne Polysaccharides on Functional Constipation
  66. Structural Properties and Nonlinear Optical Responses of Halogenated Compounds: A DFT Investigation on Molecular Modelling
  67. DMFDMA catalyzed synthesis of 2-((Dimethylamino)methylene)-3,4-dihydro-9-arylacridin-1(2H)-ones and their derivatives: in-vitro antifungal, antibacterial and antioxidant evaluations
  68. Production of Methanol as a Fuel Energy from CO2 Present in Polluted Seawater - A Photocatalytic Outlook
  69. Study of different extraction methods on finger print and fatty acid of raw beef fat using fourier transform infrared and gas chromatography-mass spectrometry
  70. Determination of trace fluoroquinolones in water solutions and in medicinal preparations by conventional and synchronous fluorescence spectrometry
  71. Extraction and determination of flavonoids in Carthamus tinctorius
  72. Therapeutic Application of Zinc and Vanadium Complexes against Diabetes Mellitus a Coronary Disease: A review
  73. Study of calcined eggshell as potential catalyst for biodiesel formation using used cooking oil
  74. Manganese oxalates - structure-based Insights
  75. Topological Indices of H-Naphtalenic Nanosheet
  76. Long-Term Dissolution of Glass Fibers in Water Described by Dissolving Cylinder Zero-Order Kinetic Model: Mass Loss and Radius Reduction
  77. Topological study of the para-line graphs of certain pentacene via topological indices
  78. A brief insight into the prediction of water vapor transmissibility in highly impermeable hybrid nanocomposites based on bromobutyl/epichlorohydrin rubber blends
  79. Comparative sulfite assay by voltammetry using Pt electrodes, photometry and titrimetry: Application to cider, vinegar and sugar analysis
  80. MicroRNA delivery mediated by PEGylated polyethylenimine for prostate cancer therapy
  81. Reversible Fluorescent Turn-on Sensors for Fe3+ based on a Receptor Composed of Tri-oxygen Atoms of Amide Groups in Water
  82. Sonocatalytic degradation of methyl orange in aqueous solution using Fe-doped TiO2 nanoparticles under mechanical agitation
  83. Hydrotalcite Anchored Ruthenium Catalyst for CO2 Hydrogenation Reaction
  84. Production and Analysis of Recycled Ammonium Perrhenate from CMSX-4 superalloys
  85. Topical Issue on Agriculture
  86. New phosphorus biofertilizers from renewable raw materials in the aspect of cadmium and lead contents in soil and plants
  87. Survey of content of cadmium, calcium, chromium, copper, iron, lead, magnesium, manganese, mercury, sodium and zinc in chamomile and green tea leaves by electrothermal or flame atomizer atomic absorption spectrometry
  88. Biogas digestate – benefits and risks for soil fertility and crop quality – an evaluation of grain maize response
  89. A numerical analysis of heat transfer in a cross-current heat exchanger with controlled and newly designed air flows
  90. Freshwater green macroalgae as a biosorbent of Cr(III) ions
  91. The main influencing factors of soil mechanical characteristics of the gravity erosion environment in the dry-hot valley of Jinsha river
  92. Free amino acids in Viola tricolor in relation to different habitat conditions
  93. The influence of filler amount on selected properties of new experimental resin dental composite
  94. Effect of poultry wastewater irrigation on nitrogen, phosphorus and carbon contents in farmland soil
  95. Response of spring wheat to NPK and S fertilization. The content and uptake of macronutrients and the value of ionic ratios
  96. The Effect of Macroalgal Extracts and Near Infrared Radiation on Germination of Soybean Seedlings: Preliminary Research Results
  97. Content of Zn, Cd and Pb in purple moor-grass in soils heavily contaminated with heavy metals around a zinc and lead ore tailing landfill
  98. Topical Issue on Research for Natural Bioactive Products
  99. Synthesis of (±)-3,4-dimethoxybenzyl-4-methyloctanoate as a novel internal standard for capsinoid determination by HPLC-ESI-MS/MS(QTOF)
  100. Repellent activity of monoterpenoid esters with neurotransmitter amino acids against yellow fever mosquito, Aedes aegypti
  101. Effect of Flammulina velutipes (golden needle mushroom, eno-kitake) polysaccharides on constipation
  102. Bioassay-directed fractionation of a blood coagulation factor Xa inhibitor, betulinic acid from Lycopus lucidus
  103. Antifungal and repellent activities of the essential oils from three aromatic herbs from western Himalaya
  104. Chemical composition and microbiological evaluation of essential oil from Hyssopus officinalis L. with white and pink flowers
  105. Bioassay-guided isolation and identification of Aedes aegypti larvicidal and biting deterrent compounds from Veratrum lobelianum
  106. α-Terpineol, a natural monoterpene: A review of its biological properties
  107. Utility of essential oils for development of host-based lures for Xyleborus glabratus (Coleoptera: Curculionidae: Scolytinae), vector of laurel wilt
  108. Phenolic composition and antioxidant potential of different organs of Kazakh Crataegus almaatensis Pojark: A comparison with the European Crataegus oxyacantha L. flowers
  109. Isolation of eudesmane type sesquiterpene ketone from Prangos heyniae H.Duman & M.F.Watson essential oil and mosquitocidal activity of the essential oils
  110. Comparative analysis of the polyphenols profiles and the antioxidant and cytotoxicity properties of various blue honeysuckle varieties
  111. Special Issue on ICCESEN 2017
  112. Modelling world energy security data from multinomial distribution by generalized linear model under different cumulative link functions
  113. Pine Cone and Boron Compounds Effect as Reinforcement on Mechanical and Flammability Properties of Polyester Composites
  114. Artificial Neural Network Modelling for Prediction of SNR Effected by Probe Properties on Ultrasonic Inspection of Austenitic Stainless Steel Weldments
  115. Calculation and 3D analyses of ERR in the band crack front contained in a rectangular plate made of multilayered material
  116. Improvement of fuel properties of biodiesel with bioadditive ethyl levulinate
  117. Properties of AlSi9Cu3 metal matrix micro and nano composites produced via stir casting
  118. Investigation of Antibacterial Properties of Ag Doped TiO2 Nanofibers Prepared by Electrospinning Process
  119. Modeling of Total Phenolic contents in Various Tea samples by Experimental Design Methods
  120. Nickel doping effect on the structural and optical properties of indium sulfide thin films by SILAR
  121. The effect mechanism of Ginnalin A as a homeopathic agent on various cancer cell lines
  122. Excitation functions of proton induced reactions of some radioisotopes used in medicine
  123. Oxide ionic conductivity and microstructures of Pr and Sm co-doped CeO2-based systems
  124. Rapid Synthesis of Metallic Reinforced in Situ Intermetallic Composites in Ti-Al-Nb System via Resistive Sintering
  125. Oxidation Behavior of NiCr/YSZ Thermal Barrier Coatings (TBCs)
  126. Clustering Analysis of Normal Strength Concretes Produced with Different Aggregate Types
  127. Magnetic Nano-Sized Solid Acid Catalyst Bearing Sulfonic Acid Groups for Biodiesel Synthesis
  128. The biological activities of Arabis alpina L. subsp. brevifolia (DC.) Cullen against food pathogens
  129. Humidity properties of Schiff base polymers
  130. Free Vibration Analysis of Fiber Metal Laminated Straight Beam
  131. Comparative study of in vitro antioxidant, acetylcholinesterase and butyrylcholinesterase activity of alfalfa (Medicago sativa L.) collected during different growth stages
  132. Isothermal Oxidation Behavior of Gadolinium Zirconate (Gd2Zr2O7) Thermal Barrier Coatings (TBCs) produced by Electron Beam Physical Vapor Deposition (EB-PVD) technique
  133. Optimization of Adsorption Parameters for Ultra-Fine Calcite Using a Box-Behnken Experimental Design
  134. The Microstructural Investigation of Vermiculite-Infiltrated Electron Beam Physical Vapor Deposition Thermal Barrier Coatings
  135. Modelling Porosity Permeability of Ceramic Tiles using Fuzzy Taguchi Method
  136. Experimental and theoretical study of a novel naphthoquinone Schiff base
  137. Physicochemical properties of heat treated sille stone for ceramic industry
  138. Sand Dune Characterization for Preparing Metallurgical Grade Silicon
  139. Catalytic Applications of Large Pore Sulfonic Acid-Functionalized SBA-15 Mesoporous Silica for Esterification
  140. One-photon Absorption Characterizations, Dipole Polarizabilities and Second Hyperpolarizabilities of Chlorophyll a and Crocin
  141. The Optical and Crystallite Characterization of Bilayer TiO2 Films Coated on Different ITO layers
  142. Topical Issue on Bond Activation
  143. Metal-mediated reactions towards the synthesis of a novel deaminolysed bisurea, dicarbamolyamine
  144. The structure of ortho-(trifluoromethyl)phenol in comparison to its homologues – A combined experimental and theoretical study
  145. Heterogeneous catalysis with encapsulated haem and other synthetic porphyrins: Harnessing the power of porphyrins for oxidation reactions
  146. Recent Advances on Mechanistic Studies on C–H Activation Catalyzed by Base Metals
  147. Reactions of the organoplatinum complex [Pt(cod) (neoSi)Cl] (neoSi = trimethylsilylmethyl) with the non-coordinating anions SbF6– and BPh4–
  148. Erratum
  149. Investigation on Two Compounds of O, O’-dithiophosphate Derivatives as Corrosion Inhibitors for Q235 Steel in Hydrochloric Acid Solution
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