Effects of Sphingomonas sp. GY2B on the structure and physicochemical properties of stearic acid-modified montmorillonite in the biodegradation of phenanthrene

2018 ◽  
Vol 156 ◽  
pp. 36-44 ◽  
Author(s):  
Bo Ruan ◽  
Pingxiao Wu ◽  
Xiaolin Lai ◽  
Huimin Wang ◽  
Liping Li ◽  
...  
2017 ◽  
Vol 23 (9) ◽  
pp. 890-899 ◽  
Author(s):  
Jeong-Woong Seo ◽  
Kyu-Min Hwang ◽  
Sung-Hoon Lee ◽  
Dong-Wook Kim ◽  
Eun-Seok Park

2020 ◽  
Author(s):  
Kang Peng ◽  
Hongjie Wang ◽  
Pengfei wan ◽  
Jianwei Wang ◽  
Hua Luo ◽  
...  

Abstract Thermal energy storage technology plays a crucial role in the thermal management system. Clay based organic phase change material has considerable advantages in the application of thermal energy storage due to low cost and high energy storage capacity. However, the low thermal conductivity of clay, especially poor interfacial thermal transfer, limits its thermal energy storage efficiency. Herein, stearic acid/reduced graphene oxide modified montmorillonite composites (SA/RGO-MMT) were prepared by the vacuum impregnation of stearic acid into graphene modified montmorillonite matrix, which was obtained via the in situ reduction of graphene oxide on the surface of montmorillonite. Stearic acid is assembled in the porous structures of RGO-MMT with the physical interactions. SA/RGO-MMT possesses high melting enthalpy of 159 J/g, low extent of supercooling of 1.4 oC and excellent thermal reliability after 100 thermal cycling. Energy storage and release rates of SA/RGO-MMT were significantly improved due to the enhanced interfacial thermal transfer by graphene. Therefore, SA/RGO-MMT is a promising form-stable phase change material for applications in solar heat storage fields. The strategy in this study highlights the importance of enhancing interfacial thermal transfer for the efficient thermal energy storage materials.


2014 ◽  
Vol 1060 ◽  
pp. 95-98
Author(s):  
Nawinda Chinatangkul ◽  
Narumol Phosrithong ◽  
Nantana Nuchtavorn ◽  
Teedanai Rattanapit ◽  
Chonnawat Mongkol ◽  
...  

Clerodendrum disparifolium is a Thai herbal medicine, which is used for the treatment of insect bites and sting reactions by applying finely crushed leaves to the inflamed area. However, this usage is inconvenient. The study aimed to develop gel-and cream-based formulations containing 0.5 %w/v of C. disparifolium extract, and evaluate their physicochemical properties. Different topical formulations were prepared using Carbopol 934 for gels and stearic acid for creams by varying their concentrations. The results showed that gel-based formulation containing Carbopol 934 in the range of 0.5-1.0 %w/w had good appearance, appropriate spreadability (7.30-8.70 cm) and viscosity (33,100-68,920 centipoise (cps)). The pH of gel-based formulation ranged from 6.01 to 6.11. For cream-based formulation containing 10-12 % w/w of stearic acid exhibited good physicochemical characteristics. The spreadability, viscosity and pH were 5.00-5.50 cm, 110,050-174,900 cps and 6.03-6.08, respectively. The results provided the suitable formulations, which should be continuously developed for large-scale pharmaceutical production.


RSC Advances ◽  
2016 ◽  
Vol 6 (102) ◽  
pp. 100373-100382 ◽  
Author(s):  
Piotr Natkański ◽  
Anna Rokicińska ◽  
Anna Wach ◽  
Marek Drozdek ◽  
Barbara Dudek ◽  
...  

CuO-modified montmorillonite was synthesized by the template-assisted route.


2007 ◽  
Vol 9 (2) ◽  
pp. 65-67 ◽  
Author(s):  
Agnieszka Marcewicz-Kuba ◽  
Danuta Olszewska

Application of recycled natural aluminasilicate doped with vanadium for the decontamination of the air This paper reports studies on the influence of vanadium concentration on the catalytic activity of DESONOX catalysts (in DESOX reaction) based on modified montmorillonite from Jelsovy Potok. The investigation of the influence on the physicochemical properties of the catalysts on their behaviour has also been studied.


Author(s):  
Omer Adam Omer Ishag ◽  
Ayat A. Khalid ◽  
Amina Abdi ◽  
Ibrahim Yaagoub Erwa ◽  
Awadalla Babiker Omer ◽  
...  

Aims: The aims of this study were to investigate the proximate composition of flaxseed; physiochemical properties and antioxidant activity of flaxseed. Study Design: Using standard analytical methods to determine the proximate composition of flaxseed, extraction of flaxseed in different trials under the same conditions using two different solvents and investigating their physicochemical properties and antioxidant activity. Place and Duration of Study: This study was conducted in the laboratory of department of applied and industrial chemistry, International University of Africa, University of Medical Sciences and Technology and National Centre for Research, Khartoum – Sudan, during June 2019. Methodology: The prepared sample of flaxseeds was tested for proximate composition and then extracted with petroleum ether and n-hexane. The extracted oil was then subjected to physicochemical analysis, GC-MS analysis and antioxidant activity test. Results: The oil yield of flaxseed was high 21.95% and 28.29% with n-hexane and petroleum ether respectively. The results obtained for proximate composition were: moisture (8.50 ± 0.49%), ash (1.96 ± 0.00%), fiber (20.23 ± 3.47%), protein (21.00 ± 0.74%),fat (43.17 ± 0.99%) and carbohydrate (5.14 ± 2.73%).The physicochemical properties of n-hexane and petroleum ether extracted flaxseed oils were: density (0.92 ± 0.00 g/cm3), refractive index (1.47 ± 0.00 and 1.48 ± 0.01 at 28°C), acid value (0.76 ± 0.10 and 0.75 ± 0.20 mg KOH/g), peroxide value (4.67 ± 1.00 and 2.69 ± 0.55 meq O2/kg), saponification value (185.61 ± 0.56 and 187.83 ± 2.08 mg KOH/g oil), unsaponifiable matter (5.57 ± 0.64 and 2.83 ± 0.23 mg KOH/g oil) and iodine value (97.24 ± 0.86 and 97.44 ± 2.93 g/100 g) respectively. Statistical analysis showed no significant difference between the means of the two data sets of physicochemical properties of flaxseed oils extracted with the two solvents used at 95% confidence level. The GC-MS spectrum of flaxseed oil extracted with n-Hexane revealed presence of 27 fatty acids, the predominant were linoleic acid (46.53%), palmitic acid (18.04%), stearic acid (12.23%), linolenic acid (11.63%) and oleic acid (4.24%). While for petroleum ether extract a total of 28 fatty acids were identified the major were: linolenic acid (42.39%), linoleic acid (26.17%), palmitic acid (12.89%), stearic acid (10.73%) and  methyl erucic (1.24%.). The oils also, showed good antioxidant activity in relation to control; 28 ± 0.09 (DPPH) for n-Hexane extract and 26 ± 0.05 (DPPH) for petroleum ether extract. Conclusion: Based on the results obtained flaxseed and flaxseed oil had good potential for human consumption and can be used for other application.


2021 ◽  
Vol 12 (2-2021) ◽  
pp. 282-284
Author(s):  
A. D. Shirokikh ◽  
◽  
M. Y. Koroleva ◽  
E. V. Yurtov ◽  
◽  
...  

In this work, we studied the effect of yttrium stearate on the physicochemical properties of dispersions of solid lipid nanoparticles composed of stearic acid stabilized with nonionic surfactants (Tween 60, Span 60). The results showed that an increase in the concentration of yttrium stearate leads to increasing kinetic stability and decreasing the average size of the aggregates. Along with this, the average size of single particles remains practically unchanged and amounts to 35±5 nm.


Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6286
Author(s):  
Katarzyna Rucińska ◽  
Zbigniew Florjańczyk ◽  
Maciej Dębowski ◽  
Tomasz Gołofit ◽  
Rafał Malinowski

New organophilic montmorillonites with oligomers of lactic acid and other compounds such as citric acid, stearic acid, maleic anhydride, pentaerythritol and ε-caprolactone were synthesized. They were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM), elemental analysis and swelling capacity in water. In all tested composites, an increase in the montmorillonite interlayer distance resulting from intercalation of the modifying substance in the montmorillonite was found by means of XRD. Elemental analysis and FTIR showed that all of the tested samples contained an organic segment in the montmorillonite structure. TGA studies revealed that composites modified with lactic acid oligomers, stearic acid or ε-caprolactone had the highest thermal stability. They also exhibited the lowest swelling capacity which was 2–3 times lower than that for unmodified sodium montmorillonite. Some preliminary studies on the mechanical properties of PLA/modified montmorillonite are also presented and discussed.


2017 ◽  
Vol 138 ◽  
pp. 100-106 ◽  
Author(s):  
Kang Peng ◽  
Liangjie Fu ◽  
Xiaoyu Li ◽  
Jing Ouyang ◽  
Huaming Yang

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