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991.
Rayees Ahmad Sheikh Sheikh Shreaz Guruaribam Shashikumar Sharma Luqman Ahmad Khan Athar Adil Hashmi 《Journal of Saudi Chemical Society》2012,16(4):353-361
A new organylborate ligand, potassium hydro (phthalyl) (salicylyl) borate and its Co(II), Ni(II), and Cu(II) complexes were synthesized. The compounds were characterized by elemental analysis, FTIR, 1H NMR, ESI MS, UV–Vis techniques, molar conductivity and magnetic data measurements. The spectroscopic data support a distorted square planar geometry around the Cu(II) ion, while the Co(II) and Ni(II) ions acquire a distorted octahedral geometry. These synthesised compounds were also tested for their in vitro antimicrobial activities against some bacterial and fungal strains to assess their inhibiting potential and the activities shown by these complexes were compared with standard drugs. Results showed that there is a marked increase in the antibacterial and antifungal activities of the cobalt(II) complex than the free ligand and other complexes when treated against the same microorganism at the same concentration. 相似文献
992.
Mohd Syafiq Zulfakar Huda Abdullah Wan Nasarudin Wan Jalal Zalita Zainuddin Sarada Idris 《Journal of Sol-Gel Science and Technology》2014,71(3):413-420
Sol–gel method was used to synthesize zinc aluminate (ZnAl2O4) dispersed into silica matrix with different compositions of x. Morphological structure of (1?x)ZnAl2O4–xSiO2 samples were investigated by field emission scanning electron microscope (FESEM) and X-ray diffractometer (XRD). The FESEM images showed spherical structures and agglomerated particles occurred inside the samples. XRD analysis indicated the cubic phase formation of the samples. The crystallite size, D was calculated and it was found that the crystallite size are slightly increased from 8 to 17 nm. FTIR spectra analysis shows that the water presence in the samples and also the presence of nitrate group. The dielectric properties have been measured, ε r value was found to be around 13.0. The S11 parameter analysis shows the samples was resonated at 2.40 GHz and gives different values of bandwidth for microstrip patch antenna application. 相似文献
993.
Waqas Jamil Darshana Kumari Muhammad Taha Muhammad Naseem Khan Mohd Syukri Baharudin Muhammad Ali M. Kanwal Muhammad Saleem Lashari Khalid Muhammad Khan 《Journal of the Iranian Chemical Society》2018,15(11):2441-2454
A series of 1,2,4-triazole hydrazones 1–25 has been synthesized and characterized using different spectroscopic techniques including FT-IR, 1H-NMR, and ESI MS spectrometry. The synthetic derivatives were evaluated for their β-glucuronidase enzyme inhibition properties. Among them, 17 compounds demonstrated potential inhibitory activity towards β-glucuronidase with IC50 values ranging between 2.50 and 53.70 µM. Compounds 1 having IC50?=?2.50?±?0.01 µM was found to be the most active compound of the series and showed remarkable activity and found to be far more potent than the standard d-saccharic acid 1,4-lactone (IC50?=?48.4?±?1.25 µM). Furthermore, the possible binding interaction of active compounds was explored by in silico studies. These compounds can be used for anti-diabetic drug development process. 相似文献
994.
The present work deals with the theoretical study of conformational equilibrium of calix[4]tetrolarenes (1,2,3 trimethoxy substituted calix[4]arene) in gaseous and solvation phases. A total of 64 calculations (four conformations at eight level of theories) were performed using Density Functional Theory (DFT) functionals viz. wB97XD, B97D, B3LYP, CAM-B3LYP with diffused (6–31 + G(d)) and non-diffused basis sets (6-31G(d)). It has been found that the conformational profile of calix[4]tetrolarene changes from cone to 1,3-Alternate upon incorporating – OMe group. The B97D and wB97XD functionals gave the most accurate result having rmsd value ~0.73Å followed by B3LYP and CAM-B3LYP > 0.78Å. Furthermore, NBO calculations demonstrated that reduction in charges at lower rim oxygens reduces the chances of hydrogen bonding. Moreover, global reactivity parameters and molecular dynamics also complement the observed trend. Owing to the methoxy substitutions, anion binding study of these new molecules indicates towards the promising capability to bind Cl? and F? ions. 相似文献
995.
Polylactic acid incorporated polyfurfuryl alcohol bioplastics: thermal,mechanical and curing studies
Mohd Sharib Rakesh Kumar K. Dinesh Kumar 《Journal of Thermal Analysis and Calorimetry》2018,132(3):1593-1600
Biodegradable polyfurfuryl alcohol (PFA)-based bioplastics, containing 0.5% to 3% (w/v) dissolvable polylactic acid (PLA) fabric, were successfully fabricated with p-toluene sulphonic acid as an acid catalyst by casting method in a silicon mould. By incorporating PLA, the 1st step thermal curing time of acid-catalysed furfuryl alcohol decreased from 96 h to 22 h. The fabricated bioplastics were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry and tensile testing to evaluate their structure and properties. The results revealed that PFA-based bioplastics with 0.5% PLA showed higher tensile strength as well as higher elongation at break compared to neat PFA-based bioplastics. Also, the thermal stability of PFA bioplastic at 0.5% PLA increased compared to neat PFA. A “green” and solvent-free method for incorporating PLA in PFA resin to fabricate PLA incorporated PFA-based bioplastics has been delineated in this work. 相似文献
996.
Wan Sharifatun Handayani Wan Zullkiplee Maya Asyikin Mohd Ariff Hasnain Hussain Wan M. Khairul 《Phosphorus, sulfur, and silicon and the related elements》2016,191(10):1329-1333
A series of tri-substituted thiourea derivatives were synthesized by the reaction of 1,3,5-triacetylbenzoyl isothiocyanate with aminoacids and aniline derivatives. All thiourea derivatives were characterized by FT-IR, 1H and 13C NMR spectroscopy. Antibacterial activities against wild-type Escherichia coli American Type Culture Collection 8739 were determined by use of the turbidimetric methodto evaluate the effect of varying amino groups on the synthesized thioureas. Tris-thiourea derivatives bearing ortho-chloroaryl substituents showed excellent antibacterial activity against E. coli with minimal inhibitory concentration (MIC) of 96 ppm. The optimum inhibition was dependent on the type of amines and the position of the halogen in aniline. 相似文献
997.
Loong Chuen Lee Muhammad Ismail Ab Samad Mohamad Azlan Mohd Ismail 《Journal of Analytical Chemistry》2016,71(7):723-729
As a non-destructive analytical method, Raman spectroscopy often provides insufficient information to identify or differentiate the ink used for the preparation of a questioned document. In this study, blue and black ballpoint pen inks deposited on paper substrate were examined in situ by conventional Raman spectroscopy. Inks were successfully classified based on the total number of prominent bands in Raman spectra. It was found that more than 90% of the samples of the same type and color could be differentiated visually using only Raman spectra, i.e. 94 and 95% for blue and black inks, respectively. As a result of this study, a flow chart has been constructed for blue and black ballpoint pen inks allowing their systematic identification. Raman spectroscopy proved to be a fast and precise technique for forensic ink analysis. 相似文献
998.
Agarose‐ and alginate‐based biopolymers for sample preparation: Excellent green extraction tools for this century 下载免费PDF全文
Mohd Marsin Sanagi Saw Hong Loh Wan Nazihah Wan Ibrahim Neda Pourmand Ahmed Salisu Wan Aini Wan Ibrahim Imran Ali 《Journal of separation science》2016,39(6):1152-1159
Recently, there has been considerable interest in the use of miniaturized sample preparation techniques before the chromatographic monitoring of the analytes in unknown complex compositions. The use of biopolymer‐based sorbents in solid‐phase microextraction techniques has achieved a good reputation. A great variety of polysaccharides can be extracted from marine plants or microorganisms. Seaweeds are the major sources of polysaccharides such as alginate, agar, agarose, as well as carrageenans. Agarose and alginate (green biopolymers) have been manipulated for different microextraction approaches. The present review is focused on the classification of biopolymer and their applications in multidisciplinary research. Besides, efforts have been made to discuss the state‐of‐the‐art of the new microextraction techniques that utilize commercial biopolymer interfaces such as agarose in liquid‐phase microextraction and solid‐phase microextraction. 相似文献
999.
The Application of Graphene and Its Derivatives to Energy Conversion,Storage, and Environmental and Biosensing Devices 下载免费PDF全文
Asif Ali Tahir Habib Ullah Pitchaimuthu Sudhagar Mohd Asri Mat Teridi Anitha Devadoss Senthilarasu Sundaram 《Chemical record (New York, N.Y.)》2016,16(3):1591-1634
Graphene (GR) and its derivatives are promising materials on the horizon of nanotechnology and material science and have attracted a tremendous amount of research interest in recent years. The unique atom‐thick 2D structure with sp2 hybridization and large specific surface area, high thermal conductivity, superior electron mobility, and chemical stability have made GR and its derivatives extremely attractive components for composite materials for solar energy conversion, energy storage, environmental purification, and biosensor applications. This review gives a brief introduction of GR's unique structure, band structure engineering, physical and chemical properties, and recent energy‐related progress of GR‐based materials in the fields of energy conversion (e.g., photocatalysis, photoelectrochemical water splitting, CO2 reduction, dye‐sensitized and organic solar cells, and photosensitizers in photovoltaic devices) and energy storage (batteries, fuel cells, and supercapacitors). The vast coverage of advancements in environmental applications of GR‐based materials for photocatalytic degradation of organic pollutants, gas sensing, and removal of heavy‐metal ions is presented. Additionally, the use of graphene composites in the biosensing field is discussed. We conclude the review with remarks on the challenges, prospects, and further development of GR‐based materials in the exciting fields of energy, environment, and bioscience. 相似文献
1000.
Saiful Izwan Abd Razak Farah Nuruljannah Dahli Izzati Fatimah Wahab Mohammed Rafiq Abdul Kadir Ida Idayu Muhamad Abdul Halim Mohd Yusof 《Soft Materials》2016,14(2):78-86
This paper reports for the first time a simple yet effective method for fabricating a conductive and highly porous scaffold material made up of polylactic acid (PLA) and conducting polyaniline (PANI). The electrical percolation state was successfully obtained at 3 wt% of PANI inclusions and reached a conductivity level of useable tissue engineering applications at 4 wt%. In addition, preliminary bioactivity test results indicated that the protonating agent could form a chelate at the scaffold surface leading to good in-vitro apatite forming ability during biomimetic immersion. This new conductive scaffold has potential as a suitable biomedical material that requires electrical conductivity. 相似文献