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101.
Mohd Nasir M. N. Al-Mansoori M. H. Abdul Rashid H. A. Choudhury P. K. Yusoff Z. 《Laser Physics》2008,18(4):446-448
In this paper, we demonstrate a multiwavelength Brillouin erbium fiber laser in a Fabry-Perot cavity. The design utilized a bidirectional oscillation provided by a fiber Bragg grating filter and a fiber loop mirror at each end of the laser cavity. A stable operation of 25 Brillouin-Stokes lines was obtained at around a 1559-nm band. 相似文献
102.
Chaitanya A. K. Koppisetty Waqas Nasir Francesco Strino Gustaf E. Rydell Göran Larson Per-Georg Nyholm 《Journal of computer-aided molecular design》2010,24(5):423-431
Norovirus strains are known to cause recurring epidemics of winter vomiting disease. The crystal structure of the capsid protein
of VA387, a representative of the clinically important GII.4 genocluster, was recently solved in complex with histo-blood
group A- and B-trisaccharides. However, the VA387 strain is known to bind also to other natural carbohydrates for which detailed
structural information of the complexes is not available. In this study we have computationally explored the fit of the VA387
with a set of naturally occurring carbohydrate ligands containing a terminal α1,2-linked fucose. MD simulations both with
explicit and implicit solvent models indicate that type 1 and 3 extensions of the ABO-determinant including ALeb and BLeb pentasaccharides can be well accommodated in the site. Scoring with Glide XP indicates that the downstream extensions of
the ABO-determinants give an increase in binding strength, although the α1,2-linked fucose is the single strongest interacting
residue. An error was discovered in the geometry of the GalNAc-Gal moiety of the published crystal structure of the A-trisaccharide/VA387
complex. The present modeling of the complexes with histo-blood group A-active structures shows some contacts which provide
insight into mutational data, explaining the involvement of I389 and Q331. Our results can be applicable in structure-based
design of adhesion inhibitors of noroviruses. 相似文献
103.
A new and convenient spectrophotometric method for the estimation of vanadium(IV) with NTA is described. The minimum ratio of metal ion to ligand, working pH, wavelength for maximum absorbance of the complex ion, and the effect of various cations and anions are described. The complex ion obeys Beer's law in the concentration range 1–32 mmol/liter of the vanadium(IV) ion. It is observed that iron(II), cobalt(II), nickel(II), copper(II), and oxidizing anions such as chromate and nitrite interfere in this determination, whereas managanese(II), chromium(III), iron(III), and anions like nitrate, chloride, bromide, iodide, thiocyanate, sulfate, and sulfite do not have any effect. Excessive amounts of acetate, phosphate, oxalate, tartrate and thiosulfate must also be avoided in this determination. Anions and cations which interfere in the determination of vanadium(IV) by NTA should not be present in the system. 相似文献
104.
Raja Muhammad Asif Khan Habib Nasir Azhar Mahmood Mudassir Iqbal Hussnain A. Janjua Nasir M. Ahmad 《先进技术聚合物》2024,35(3):e6350
Polyethersulfone (PES) membranes are prevalent in the field of water treatment owing to their exceptional separation efficiency, robust mechanical properties, and resistance to chemical degradation. Nevertheless, these membranes are prone to fouling, resulting in a decrease in both flux and ultrafiltration efficiency. In the present study, PES membranes are blended with poly (3-Sulfopropyl Methacrylate) (PSPMA) in various weight percentages (0%–3%) to improve their antifouling and ultrafiltration properties. The physicochemical properties of the blended membranes, including surface morphology, contact angle, hydrophilicity and surface energy are evaluated. The findings indicate that incorporation PSPMA results in an enhancement of the hydrophilic properties and surface charge of the PES membranes, assessed by employing Bovine Serum Albumin (BSA) as a representative protein. Modified blended membranes display greater Flux Recovery Ratio (FRR%) and exhibit superior fouling resistance. Under the same experimental conditions (0.2 MPa applied pressure), a pure water flux of 154.18 L·m−2·h−1 for PES/PSPMA membrane found substantially greater than pure PES membrane (103.52 L·m−2·h−1) along with Total Fouling Ratio (TFR) of 36% and 64.9% respectively. Exceptional antimicrobial efficacy for modified membranes is revealed against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) using disc diffusion technique rendering them well-suited for water treatment applications. 相似文献
105.
Mehrazar Mehrdad Hassankalhori Mahdi Toolabi Mahsa Goli Fereshteh Moghimi Setareh Nadri Hamid Bukhari Syed Nasir Abbas Firoozpour Loghman Foroumadi Alireza 《Molecular diversity》2020,24(4):997-1013
Molecular Diversity - A new series of compounds based on benzodiazepine-1,2,3-triazole were synthesized and evaluated as cholinesterase inhibitors by Ellman’s method. The compounds proved to... 相似文献
106.
The effect of temperature and slice thickness on drying kinetics tomato in the infrared dryer 总被引:1,自引:0,他引:1
In this study thin layer drying of tomato slices were investigated in the infrared dryer. Drying rate increased with increasing temperature and reduction thickness and thus reduced the drying time. The effective diffusivity increased with increasing temperature and with increasing thickness of the samples. The effective diffusivity values changed from 1.094 × 10?9 to 4.468 × 10?9 m2/s and for activation energy varied from 110 to 120 kJ/mol. The best model for drying process of tomato slices was Midilli model. 相似文献
107.
Mr. Rasool Babaahmadi Dr. Ayan Dasgupta Prof. Christopher J. T. Hyland Prof. Brian F. Yates Prof. Rebecca L. Melen Prof. Alireza Ariafard 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(11):e202104376
Diazo compounds have been largely used as carbene precursors for carbene transfer reactions in a variety of functionalization reactions. However, the ease of carbene generation from the corresponding diazo compounds depends upon the electron donating/withdrawing substituents either side of the diazo functionality. These groups strongly impact the ease of N2 release. Recently, tris(pentafluorophenyl)borane [B(C6F5)3] has been shown to be an alternative transition metal-free catalyst for carbene transfer reactions. Herein, a density functional theory (DFT) study on the generation of carbene species from α-aryl α-diazocarbonyl compounds using catalytic amounts of B(C6F5)3 is reported. The significant finding is that the efficiency of the catalyst depends directly on the nature of the substituents on both the aryl ring and the carbonyl group of the substrate. In some cases, the boron catalyst has negligible effect on the ease of the carbene formation, while in other cases there is a dramatic reduction in the activation energy of the reaction. This direct dependence is not commonly observed in catalysis and this finding opens the way for intelligent design of this and other similar catalytic reactions. 相似文献
108.
The cyclization of β-ketosulfone, β-ketonitrile and β-ketophosphonate dianions with 1,1-diacetylcyclopropane afforded 1-hydroxyspiro[5.2]cyclooct-4-en-3-ones, which were transformed, by reaction with tetrabutylammonium halides, into functionalized phenols containing a remote halide function. 相似文献
109.
The ethyl acetate soluble part of the chloroform extract of Pulicaria gnaphalodes belonging to the family Asteraceae afforded a new sesquiterpene-dimer of guaiane class named as gnapholide and anabsinthin of the same skeleton. The structures of both the compounds were elucidated with the aid of spectroscopic techniques including 2D NMR. 相似文献
110.
Zakaullah M. Alamgir K. Rasool A. Shafiq M. Murtaza G. Waheed A. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2001,29(1):62-68
Correlation of neutron emission with plasma electron temperature in a low-energy (2.3 kJ) plasma focus is investigated. To determine the plasma temperature by continuum X-ray analysis, cobalt is selected as the filter, which discriminates the line radiation from the background impurities like carbon, nitrogen, and oxygen, or the copper of which plasma focus electrodes are made. For a pressure range of high neutron emission (1-4 mbar), the neutron yield is found to correlate with the plasma temperature. The highest temperature recorded is 5 keV at 2.5 mbar, the filling pressure for the highest neutron emission in this device 相似文献