Electric Field Controlled Separation and Capture of CO2 over S-Doped Graphene: A First-Principles Calculation

The selective adsorption and capture of CO2 from post-combustion gases carries huge significance for the reduction of greenhouse effect. In this research, the computations of density functional are performed to investigate the CO2 selective adsorption of S-doped graphene in thrall to applied electric field (E-F). Introducing the applied E-F, the adsorption between S-doped graphene and CO2 is strong chemisorption, and CO2 can be effectively captured. Removing the applied E-F, the adsorption restores to physisorption and CO2 is easily desorbed. Therefore, the CO2 seize and clearing can be realized merely by controlling the E-F. Besides, the adsorption energy of N2 (H2O) on S-decorated graphene is positive when introduce the applied E-F. The results demonstrated that S-doped graphene can selectively adsorb CO2 from the post-combustion gases by controlling the E-F.read more

Jingyi Shan, Xiangling Wang, Junkai Wang, Shixuan Zhang, Qianku Hu and Aiguo Zhou

Performance Evaluation of Coating Materials Containing Perlite-Volcanic Lava Stone-Carrot Pulp Ternary System

Cellulose in the fibrous structure, which is the main structural component in the cell wall of plants, was formed by the combination of three thousand or more glucose molecules and was a natural polymer synthesized by many living microorganisms. In this study, it was aimed to observe the performance of carrot pulp physically added to water-based coating to increase the viscosity of the coatings. In addition, volcanic lava stone (red pumice stone) and perlite stone were added to the coating to improve its properties that heat transfer, adhesion, hydrophobicity, corrosion resistance. The effect of cellulose-based material on the viscosity of the coating was determined using the Design Expert Optimization Method. In this experimental design method, the experimental set was created to be “carrot pulp, volcanic lava stone, and perlite stone” and additives was added as 0-6% by weight of the coating. By using this method, the most suitable process parameters were determined, and the effects of the additives added to the coating were examined, comparatively. As a result, it was found that cellulose derived organic additives and other additives improved the various properties of coating and could be evaluated for industrial coatings.read more

Bilge Çelik and Nil Acaralı

Investigation of the Effectiveness of Polyurethane Composites Containing Gelatin at Different Rates on the Release of Ciprofloxacin

Recently, polyurethane materials are widely used for many application areas such as drug delivery systems, biomaterial production, etc. In this study, polyurethane structures containing different amounts of gelatin (5%, 10%) were prepared. A release system was designed with ciprofloxacin adsorption to the prepared polyurethane structures. The structural characterization, thermal properties, surface morphologies of the designed system were determined using appropriate techniques. Monitoring of ciprofloxacin release was carried out by UV-spectrophotometer. It was determined that polyurethane structures containing different proportions of gelatin supported the adsorption of ciprofloxacin and the release slowed down with the increasing gelatin ratio. With this study, many drug delivery systems that can release at different rates and durations depending on the amount of gelatin additive can be designed.read more

İdil Karaca Açarı

Preparation, Characterization and Adsorptive Application of Chemically Modified Chitosan

The chitosan was cross linked with ethylene diamine and trepthaldehyde (CM-Chitosan) through Schiff base reaction. The chitosan was successfully cross linked as confirmed by FT-IR spectrometer. The morphological analysis illustrated that CM-Chitosan surface is porous/rough than neat chitosan. The CM-Chitosan and Chitosan were employed as an adsorbent for the elimination of Cu+2 and Pb+2 ions from aqueous solution. The CM-chitosan adsorbed 8.96 and 2.09 mmol/g while neat chitosan removed 6.71 and 1.58 mmol/g of Cu+2 and Pb+2 ions, respectively. The adsorption data was also best fitted to Freundlich and Temkin model.read more

Samina Begum, Syed Nusrat Shah, Falak Naz, Khalid Saeed

Electrocatalytic Hydrogenation of CO2 to Hydrocarbons on Gold Catalyst in the Presence of Ionic Liquid

This study is aimed to investigate the electro-catalytic activity of Au supported on both CeO2 and activated carbon (AC) to convert CO2 to mixture of C1-C4 hydrocarbons in the presence of ionic liquid (IL) 1-butyl-3-methylimidazolium methylsulfonate. The studied catalyst samples were prepared by using simultaneous wet impregnation method. The sample containing 0.6 % Au showed higher electro-catalytic activity than the sample contained 0.3 % Au. Both, the average Au particles size and the transformation of layered non-uniformed semi-oval structure to flaked tiny circular like-structure were mainly responsible for the higher catalytic activity of 0.6Au-CeO2-AC sample. In addition, the overall electro-catalytic activity depends upon the applied reaction voltage. Overall, the presence of IL, the surface morphology, and average Au particles size had played a key role in the electro-catalytic conversion of CO2 to hydrocarbons.read more

Arshid M. Ali, Aqeel Taimoor, Ayyaz Muhammad, Muhammad A. Daous and Usman Saeed

Hydrogen Evolution Reaction Performance of Co(II) and Co(III) Complexes Based on pyridoxal (thio)semicarbazones

Finding a renewable, cleaner and inexpensive source of energy has been a momentous challenge to the researchers. Among others, one intriguing solution is molecular H2 which is considered as an ideal energy source for the future needs. Obtaining H2 is extremely appealing but difficult to achieve. One of the most viable solutions is the electrocatalytic hydrogen evolution reaction (HER). In this paper, we presented electrocatalytic HER performances of pyridoxal-semi carbazone (PLSC) and pyridoxal S-methyl-iso-thiosemicarbazone (PLITSC) stabilized Co(II) and Co(III) complexes, i.e. ([Co(PLSC)(SO4)(H2O)2], 1) and [Co(PLITSC-H)(PLITSC-2H)].CH3OH, 2)). Both complexes catalyzed the HER in acidic media while complex 2 was found to be more active than complex 1.read more

Violeta Jevtovic, Khalaf M. Alenezi, Hani El Moll, Ashanul Haque, Salma A. Al-Zahrani Jamal Humaidi and Dragoslav Vidovic

The Metal Complexes of Natural Compounds, Usnic Acid and Naringenin Immobilized on Mesoporous Silica: Solid Phase Extraction and Oxidative Catalytic Properties

The novel semi-natural Schiff bases were synthesized with the reaction of the natural compounds usnic acid and naringenin extracted and purified in natural sources and chemically modified silica gel. Cu(II), Ni(II), Co(II) and Mn(II) complexes of the ligands were synthesized and the silica-supported ligands and their metal complexes were characterized by FT-IR, TG/DTA, SEM, EDX, ICP-OES and elemental analyses techniques. The solid-phase extraction behaviours of the novel silica-supported ligands were examined. It was found that the hybrid materials showed the very efficient adsorption properties to Cu(II), Cd(II), Pb(II) and Cr(III) metal ions maximum at pH=8-9. The metal ions could be recovered again nearly 100 % from the silica-supported ligands in the recycling experiments. The catalytic efficiencies of the metal complexes in the oxidation reactions of cyclohexane, cylohexene, cyclooctane and styrene subtrates were examined under microwave irradiation in the present of H2O2. The complexes showed very good catalytic activities in the oxidation reactions of the various tested substrates.read more

Serhan URUŞ, Ahmet ÇAKIR, İbrahim Ethem ULUÇAY and Ali ASLAN

Synthesis, Spectral Evaluation and in Silico Studies of S-Aralkylated 5-(4-methoxyphenyl)-4-phenyl-4H-1,2,4-triazole-3-thiols: As suitable Alzheimer's disease drug candidates

Our efforts lay emphasis on synthesis of S-aralkylated 5-(4-OMeC6H5)-4-phenyl-4H-1,2,4-triazol-3-thiols like pharmacologically active candidates to counter neurodegenerative disorder; Alzheimer's disease. A synthetic strategy was instigated by esterifying 4-methoxybenzoic acid through Fisher esterification's methodology. Hydrazinolysis of corresponding ester was performed under reflux with methanolic hydrated hydrazine to afford 4-methoxybenzohydrazide (I) which refluxing with phenyl isothiocyanate (II) in MeOH to yield a reactive intermediate (III). The later underwent base-catalyzed intermolecular cyclization to furnish 5-(4-OMeC6H5)-4H-1,2,4-triazol-3-thiol (IV). Ultimately, IV was aralkylated at thiol position with aralkyl halides V(a-l) in polar aprotic solvent and catalytic amounts of LiH to provide S-aralkylated 5-(4- OMeC6H5)-4-phenyl-4H-1,2,4-triazol-3-thiols VI(a-l). Modern spectral analysis data explicitly established all the substitutions on nucleophilic S-atom of parent 1,2,4-triazol-3-thiol ring. Effective anti-cholinesterase potential depicted in 3-(phenylpropylthio)-5-(4-OMeC6H5)-4-phenyl-4H-1,2,4-triazole; VIc (IC50; 3.26±0.35 μM) against acetyl cholinesterase; AChE and 3-(phenethylthio)-5-(4-OMeC6H5)-4-phenyl-4H-1,2,4-triazole; VIb (IC50; 8.52±0.54 μM) against butyrylcholinesterase; BChE enzyme as compared to standard Eserine for both enzymes (IC50; 0.04±0.01 μM). Molecular modelling analyses had been conducted to recognize the interconnection of these compounds with enzymes that suggested key interactions (Docking is made to untie the active binding sites). Anti-proliferative activity results showed VIg and VIj with -Cl groups on benzylic ring as promising candidates with HCT-116 cell viability of 14.83 % and 3.09 % respectively.read more

Muhammad Arfan, Sabahat Zahra Siddiqui, Muhammad Athar Abbasi, Aziz-ur-Rehman, Syed Adnan Ali Shah, Muhammad Ashraf, Khalid Mohammed Khan, Rahman Shah Zaib Saleem and Amna Shah Zaib

Self-Assembled Synthesis and Characterization of Novel [Co(1-vinylimidazole)6].NO3 Polymer: Highly Efficient Antimicrobial Agent

Cobalt coordination polymer i.e. [Co(1-VI)6]·NO3 was successfully synthesized with cobalt metal and (VI = vinylimidazole) and characterized by elemental analysis, FTIR, UV/Vis spectroscopy and X-ray crystallography. The structure of the compound was determined by single X-ray crystallography at temperature 296 K with a Bruker APEX II CCD diffractometer using Mo-Kα radiations (λ = 0.71073 Å), R = 0.0642 and 0.0989. Orthorhombic unit cell parameters are a = 16.1341 (6) Å, b = 16.5179(16) Å, c = 18.2664(16) Å, V= 4868.0 (8) Å, Dx = 4, Mr = 937.91. The X-ray crystallography studies showed that the compound is polymeric in nature, in which cobalt atom coordinated with six N atoms of the 1-vinylimidazole ligands in a distorted orthorhombic geometry. As-prepared compound was screened in vitro against a variety of microorganisms, such as Gram-positive (G +ve) Staphylococcusaureus (S. aureus) and Gram-negative (G -ve) Escherichia coli (E. coli) bacterial strains, and fungal species with Aspergillus niger (A. niger) and Rhizopus stolonifer(R.stolonifer)by applying disk diffusion method. MIC (minimum inhibitory concentration) value for prepared [Co(1-VI)6]·NO3 compound is 125 μg.mL-1a this MIC value cobalt polymer showed higher activity against E. coli and S. aureus () as compared to fungi including; R. StoloniferandA. Niger at 125 μg.mL-1).This study helps to reduce the risk of infectious diseases caused by various microorganisms.read more

Fouzia Chang, Najma Memon, Shahabuddin Memon, Ayaz Ali Memon, Saddam Hussain Bughio, Muhammad Nawaz Tahir and Abdul Sattar Chang

(2E)-3-(1-benzothiophen-2-yl)-1-(4-hydroxyphenyl)prop-2-en-1-one: Synthesis, Characterization (IR, NMR and UV-Vis) DFT Study and Antimicrobial Activity

In this study new chalcone derivative (2E)-3-(1-benzothiophen-2-yl)-1-(4-hydroxyphenyl)prop-2-en-1-one (I), which has important pharmacological applications, was designed and synthesized. IR, NMR and LC-MS/MS empirical methods were used in order to confirm the molecular structure of the synthesized compound I. Both two tautomeric forms of the molecule were optimized by using density functional theory (DFT) method. The structural parameters formed after optimization and structural parameters obtained from similar compounds by X-ray diffraction show a good correlation. The theoretical and experimental results of IR and NMR are generally compatible, but difference arises between some values. This difference shows the existence of O–H···O type intermolecular hydrogen bond. By using its UV-Vis data, the visible absorption maximums of the molecule were analyzed. Compound I was tested against kind of Leishmania major from the point of antileishmanial activity, against kind of Candida albicans from the point of antifungal activity and against fourteen kinds of bacteria from the point of antibacterial activity in this study. The test results showed, that compound I was effective on eight kinds of bacteria and the activity strength on six bacteria among the eight was MIC: 5000 μg/mL and on the rest two kinds MIC: 1250 μg/mL. Besides, it was also found out, that compound I has MIC: 5000 μg/mL antileishmanial activity. Since bacterial and parasitic infections form serious health problems globally, compound I may be a medication candidate in future; if its antibacterial and antiparasitic effect are taken into consideration.read more

Nevin Süleymanoğlu, Reşat Ustabaş, Fatih Eyduran, Şahin Direkel, Yasemin Ünver, Nuran Kahriman