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991.
Jing Zhang Muhammad Kamran Siddiqui Waqas Nazeer 《Petroleum Science and Technology》2019,37(4):430-435
A series of experiments have been performed to investigate the influence of reaction temperature, the equivalence ratio (ER), and blending ratio on the gas composition, tar content and higher heating value (HHV) of synthesis gas. H2 content decreased from 10.7 to 8.2% in the range of BR while CO and CH4 increased from 17.4 to 23.1% and 3.4 to 6.3%, respectively. HHV increased with BR and H2/CO showed an opposite trend. The highest HHV and H2/CO were obtained at 100%PW and 100%OS, respectively. Tar content increased from 4.8 to 9.5?g/Nm3 with BR increasing in the range because of a reduction in the endothermic nature of volatile combustion. 相似文献
992.
Asher Benjamin Daniel Erum Zahir Muhammad Asif Asghar 《Petroleum Science and Technology》2019,37(10):1143-1154
In this article, two bio-sorbents have been selected: lasani sawdust (LS) (a new bio-based material) and coconut coir (CC) for the removal of used motor oil from the aqueous phase. The physical nature of the materials was characterized using Fourier Transform Infrared Spectroscopy and Constitutional Analysis of lignin and cellulose. The adsorption process was evaluated using various kinetic and adsorption models. The evaluated sorption capacities for coconut coir and lasani sawdust were 12.82?g g?1 and 0.36?g g?1, respectively. Maximum sorption of oil from the aqueous solution conveniently took place in 20?minutes. To ascribe statistically which model describes the adsorption phenomenon best, Root Mean Square Error (RMSE) and Average Relative Error (ARE) were used. The kinetics of the adsorption was best described by Pseudo-second order. Similarly, Langmuir isotherm model had the least value for the two error functions and a higher qmax value for coir than for lasani. It was concluded that the increased absorptive ability of coir over lasani was due to the difference in the composition of lignin and cellulose of the two materials. 相似文献
993.
Kucera SA McGinity JW Zheng W Shah NH Malick AW Infeld MH 《Drug development and industrial pharmacy》2007,33(7):717-726
The objective of this study was to investigate the influence of two proteins, albumin and type B gelatin, on the physical aging of EUDRAGIT® RS 30 D and RL 30 D coated theophylline pellets. The physicomechanical properties of sprayed films, thermal properties of cast films, influence of proteins on the zeta potential and particle size of the dispersion, and the release of proteins from cast films under simulated dissolution conditions were investigated. The release rate of theophylline decreased significantly over time from pellets coated with an acrylic dispersion containing 10% albumin when there was no acidification of the acrylic dispersion; however, when pellets were coated with an acidified EUDRAGIT®/albumin dispersion, the theophylline release rate was stable for dosage forms stored in the absence of humidity. The drug release rate was faster for pellets coated with acrylic dispersions containing 10% gelatin compared to the albumin-containing formulations. When sprayed films were stored at 40°C/75% RH, the water vapor permeability decreased significantly for both EUDRAGIT® films and those containing EUDRAGIT® and albumin; however, there was no significant change in this parameter when 10% gelatin was present. Albumin was released from the acrylic films when the pH of the dissolution media was below the isoelectric point of the protein while no quantitative release of gelatin was observed in pH 1.2 or 7.4 media. The effect of gelatin to prevent the decrease in drug release rate was due to stabilization in water vapor permeability of the film. Acidification of the polymeric dispersion resulted in electrostatic repulsive forces between albumin and the acrylic polymer, which stabilized the drug release rate when the dosage forms were stored in aluminum induction sealed containers at both 40°C/75% RH and 25°C/60% RH. 相似文献
994.
Aamer Saeed Muhammad Naeem Mustafa Muhammad Zain-ul-Abideen Ghulam Shabir Mauricio F. Erben Ulrich Flörke 《Journal of Sulfur Chemistry》2019,40(3):312-350
1-(acyl/aroyl)-3-(substituted)thioureas are exciting structures in the fields of organic synthesis, material sciences, and biomedical research. Of particular significance is the fact that acyl thiourea derivatives have been demonstrated to be highly exceptional ligands and their coordination compounds have extensively been investigated in the synthesis of pharmaceuticals and agrochemical ingredients. Moreover, these structural motifs are enjoying the prestigious status as versatile synthons in heterocyclic syntheses. Therefore, the progress to introduce functionalization on the backbone of 1-(acyl/aroyl)-3-(substituted)thioureas is highly desirable. This account summarizes our efforts to capture recent documented achievements by various research groups. 相似文献
995.
Muhammad Ashram Ghassab M. Al-Mazaideh Wael Al-Zereini Ahmed Al-Mustafa Shehadeh Mizyed 《Journal of Sulfur Chemistry》2019,40(3):277-288
A series of new thiacrown ethers derived quinoline 7–9 were synthesized in good yield and in a simple way. Their transition metal ions complexation was studied using a conductometric method in acetonitrile at 25°C. Crowns 7 and 8 showed a continuous decrease in the molar conductances in their complexation with Ag+, Cu2+, Hg2+ and Zn2+ which begins to level off at a molar ratio of 1:1 crown to metal, indicating the formation of 1 stable 1:1 complex. On the other hand, crown 9 showed the formation of 1:1 complexes only with Ag+, Cu2+, Hg2+. The in vitro, a preliminary antimicrobial, antioxidant and cytotoxic effects on breast tumor cells were also reported. Five bacterial test strains were included in the present study. Antioxidant activity was measured in terms of the radical scavenging ability and decolorization of 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radicals. Cytotoxic effect of thiacrown was evaluated using MDA MB-231 cell line (human breast adenocarcinoma, ATCC HTB-26). 相似文献
996.
Shaohui Xiong Deming Yin Muhammad Umar Javaid Liang Li Chunyue Pan Juntao Tang Guipeng Yu 《Israel journal of chemistry》2019,59(9):824-831
Ionic liquids (ILs) have gained wide‐spread focus owing to its negligible vapor pressure, low heat capacity, high thermal stability, and structural diversity. The solubility and selectivity toward carbon dioxide has made ILs a unique platform that possess the potential in gas separations. In particularly, combining functional ILs with membranes and porous supports is an efficient way to design task‐specific materials for CO2 separations. This minireview summarizes the developments and advances of ionic liquids‐based membranes for CO2 separations in recent three years, with an emphasis on the strategy of incorporating ionic liquids and CO2 separation performance. 相似文献
997.
Vipin Kumar Muhammad Akhsin Muflikhun Tomohiro Yokozeki 《Polymer Engineering and Science》2019,59(5):956-963
An all polymeric electrically conductive thermoset adhesive resin system is prepared for future lightning strike protection applications. Polyaniline (PANI)‐based hybrid nano‐composite is prepared by incorporating high apparent‐density type vapor grown carbon fiber (VGCF‐H) as additional conductive filler. Electrical, mechanical and electromagnetic interference (EMI) shielding properties of PANI‐dodecylbenzene sulfonic acid (DBSA), and divinylbenzene (DVB) system are improved with addition of VGCF‐H. Different weight percentages of VGCF‐H in the PANI‐DBSA/DVB matrix, are studied, and their effect on composite's properties are investigated. Electrical conductivity up to 1.89 S/cm with the addition of 5 wt% VGCF‐H is achieved, which is almost 300% improvement compared with previous system. However, the maximum flexural modulus is obtained at 3 wt% of VGCF‐H. The change in the electronic structure of PANI with the addition of VGCF‐H is investigated using Fourier transform infrared (FT‐IR) analysis. Rheological study and Differential scanning calorimetry analysis were employed to show the effect of VGCF‐H concentration on curing profile of the nanocomposites. EMI shielding properties of the composite with and without VGCF‐H are measured in X‐band frequencies and compared. Composite with 5 wt% VGCF‐H has shown EMI shielding effectiveness about 51 dB in X‐band, which is higher than the composite without VGCF‐H (around 22 dB). POLYM. ENG. SCI., 59:956–963, 2019. © 2018 Society of Plastics Engineers 相似文献
998.
Saad Ahmed Muhammad Ali Yangben Cai Yunhua Lu Zaheer Ahmad Santosh Khannal Shiai Xu 《应用聚合物科学杂志》2019,136(22):47603
In the present study, multi-walled carbon nanotubes (MWCNTs) were sulfonated by 1,3-propane sultone and distillation–precipitation polymerization, respectively, and then incorporated into chitosan (CS) to prepare CS/MWCNTs composite membranes for fuel cell applications. CS/MWCNTs membranes show better thermal and mechanical stability than pure CS membrane due to the strong electrostatic interaction between the SO3H groups of MWCNTs and the NH2 groups of CS, which can restrict the mobility of CS chain. The sulfonated MWCNTs provide efficient proton hopping sites ( SO3H, SO3− …. 3+HN ), thereby resulting in the formation of continuous proton conducting channels. The composite membranes with 5 wt % of MWCNTs modified by two different ways show a proton conductivity of 0.026 and 0.025 S·cm−1, respectively. In conclusion, CS/MWCNTs membrane is a promising proton exchange membrane for fuel-cell applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47603. 相似文献
999.
Noresah Said Hasrinah Hasbullah Muhammad Nidzhom Zainol Abidin Ahmad Fauzi Ismail Pei Sean Goh Mohd Hafiz Dzarfan Othman Siti Hamimah Sheikh Abdul Kadir Fatmawati Kamal Mohd Sohaimi Abdullah Be Cheer Ng 《应用聚合物科学杂志》2019,136(21):47502
Protein existence in wastewater is an important issue in wastewater management because proteins are generally present as contaminants and foulants. Hence, in this study, we focused on designing a polysulfone (PSf) hollow-fiber membrane embedded with hydrophilic iron oxide nanoparticles (IONPs) for protein purification by means of ultrafiltration. Before membrane fabrication, the dispersion stability of the IONPs was enhanced by the addition of a stabilizer, namely, citric acid (CA). Next, PSf–IONP–CA nanocomposite hollow-fiber membranes were prepared via a dry–wet spinning process and then characterized in terms of their hydrophilicity and morphology. Ultrafiltration and adsorption experiments were then conducted with bovine serum albumin as a model protein. The results that an IONP/CA weight ratio of 1:20 contributed to the most stable IONP dispersion. It was also revealed that the membrane incorporated with IONP–CA at a weight ratio of 1:20 exhibited the highest pure water permeability (58.6 L m−2 h−1 bar−1) and protein rejection (98.5%) while maintaining a low protein adsorption (3.3 μg/cm2). The addition of well-dispersed IONPs enhanced the separation features of the PSf hollow-fiber membrane for protein purification. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47502. 相似文献
1000.
Saira Jabeen Sagheer Gul Ayesha Kausar Bakhtiar Muhammad Muhammad Farooq 《Polymer-Plastics Technology and Engineering》2019,58(4):427-442
A facile route was adopted to blend the matrix. The PMMA/PEG blend was reinforced with three types of nanofillers, i.e., pristine MWCNT (P-CNT), amine functionalized MWCNT (PDA-EA-CNT) and nanobifiller i.e. nanodiamond functional MWCNT (PDA-EA-CNT-ND) to yield three different types of nanocomposites i.e. PMMA/PEG/P-CNT, PMMA/PEG/PDA-EA-CNT and PMMA/PEG/PDA-EA-CNT-ND. These nanocomposites were reinforced with nanofiller loading (1 wt. %, 3 wt. %, 5 wt. %, 10 wt. %, 30 wt. % and 50 wt. %) by solution casting method. Structure of composite and nanofillers was confirmed by FTIR. FESEM imaging revealed that nanocomposites have micro porous morphology. At high magnification, distribution of functionalized CNT/ND appears to be protruding out of the polymeric matrix. The TGA result suggests that the thermal stability of the nanocomposites was enhanced in comparison to PMMA due to grafting of filler molecules with PMMA/PEG macromolecules. The DTG results showed that the bifiller nanocomposites (PMMA/PEG/PDA-EA-CNT-ND) exhibited improved thermal stability with Tmax (431°C) as compared to P-CNT and amine functionalized CNT (PMMA/PEG/PDA-EA-CNT) with Tmax of 395°C and 418°C respectively. XRD results showed fine interaction between filler and the polymeric matrix. As the filler loading was increased the composites showed pronounced XRD peak at 25.9°, corresponding to (002) reflection of nanotubes. Significant improvement in the mechanical properties of composites was recorded with the reinforcement of fillers as compared to the neat matrix. The most significant improvement in tensile strength and elastic modulus was observed for the bifiller nanocomposites with 5 wt. % PDA-EA-CNT-ND. They showed a tensile strength and elastic modulus of 29.9 MPa and 1474.31 MPa respectively as compared to amine functionalized CNT with tensile strength (25.7) and elastic modulus (1466.99 MPa)and P-CNT with tensile strength(25 MPa) and elastic modulus (1155.75 MPa). 相似文献