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951.
Syed?Muhammad?Jawwad?RiazEmail author Azad?A.?Siddiqui 《General Relativity and Gravitation》2011,43(4):1167-1178
In this paper we present non-singular coordinates for the rotating BTZ (Banados–Teitelboim–Zanelli) black hole. The approach
is further extended to construct non-singular coordinates for different cases of general circularly symmetric black holes
in 2 + 1 dimensions. 相似文献
952.
Rastegari Arezoo Safavi Maliheh Vafadarnejad Fahimeh Najafi Zahra Hariri Roshanak Bukhari Syed Nasir Abbas Iraji Aida Edraki Najmeh Firuzi Omidreza Saeedi Mina Mahdavi Mohammad Akbarzadeh Tahmineh 《Molecular diversity》2022,26(1):409-428
Molecular Diversity - Alzheimer’s disease (AD) is now ranked as the third leading cause of death after heart disease and cancer. There is no definite cure for AD due to the multi-factorial... 相似文献
953.
In this article, a novel (G'/G)-expansion method is proposed to search for the traveling wave solutions of nonlinear evolution equations. We construct abundant traveling wave solutions involving parameters to the Boussinesq equation by means of the suggested method. The performance of the method is reliable and useful, and gives more general exact solutions than the existing methods. The new (G'/G)-expansion method provides not only more general forms of solutions but also cuspon, peakon, soliton, and periodic waves. 相似文献
954.
Perpendicular magnetic tunnel junction and its application in magnetic random access memory 下载免费PDF全文
Recent progresses in magnetic tunnel junctions with perpendicular magnetic anisotropy(PMA) are reviewed and summarized. At first, the concept and source of perpendicular magnetic anisotropy(PMA) are introduced. Next, a historical overview of PMA materials as magnetic electrodes, such as the RE–TM alloys TbFeCo and GdFeCo, novel tetragonal manganese alloys Mn–Ga, L10-ordered(Co, Fe)/Pt alloy, multilayer film [Co, Fe, CoFe/Pt, Pd, Ni, Au]N, and ultra-thin magnetic metal/oxidized barrier is offered. The other part of the article focuses on the optimization and fabrication of CoFeB/MgO/CoFeB p-MTJs, which is thought to have high potential to meet the main demands for non-volatile magnetic random access memory. 相似文献
955.
Liaqat Ali Samina Ali Javid Hussain Ahmed Al‐Harrasi Abdul Latif Khan Syed Tasleem Hussain Shah Tania Shamim Rizvi 《Helvetica chimica acta》2014,97(4):556-560
The isolation and structure elucidation of a new triterpenic acid named floccosic acid ( 1 ) is reported on the basis of the 1D‐ and 2D‐NMR assignments. This secondary metabolite was isolated as a new constituent, along with the known triterpenoids, betulinic acid and β‐amyrin. All these compounds were purified by repeated column chromatography of the MeOH extract of Nepeta floccosa. The structure elucidation of the new compound was accomplished by the combined mass spectrometry (MS), infrared (IR) and ultraviolet (UV) absorption spectroscopy, one‐ (1H‐ and 13C‐) and two‐dimensional (H? C correlations; HMBC and HSQC) NMR techniques. The known compounds were identified by comparison of their physical and spectroscopic data with those reported in the literature. 相似文献
956.
An facile and efficient protocol for the synthesis of 13-aryl-indeno[1,2-b]naphtha[1,2-e]pyran- 12(13H)- ones has been developed that proceeds via the one-pot three-component sequential reaction of an aromatic aldehyde with β-naphthol and 2H-indene-1,3-dione under solvent-free conditions in the presence of a poly(4-vinylpyridinium)hydrogen sulfate (P(4-VPH)HSO4) catalyst. The catalyst can be reused several times, making this procedure facile, practical, and sustainable. The simple experimental procedure, solvent-free reaction conditions, use of an inexpensive catalyst, short react time, and excellent yields are some of the major advantages of this methodology. 相似文献
957.
Cold water fish gelatin films: Effects of cross-linking on thermal, mechanical, barrier, and biodegradation properties 总被引:1,自引:0,他引:1
Bor-Sen Chiou Roberto J. Avena-Bustillos Haani Jafri Syed H. Imam William J. Orts 《European Polymer Journal》2008,44(11):3748-3753
Gelatin was extracted from Alaska pollock (Theragra chalcogramma) and Alaska pink salmon (Oncorhynchus gorbuscha) skins and cast into films. The fish gelatin films’ tensile, thermal, water vapor permeability, oxygen permeability, and biodegradation properties were compared to those of bovine and porcine gelatin films. In addition, fish gelatin films were cross-linked with glutaraldehyde. Pollock and salmon gelatin films had comparable tensile properties, but had lower tensile strength and percent elongation than mammalian gelatin films. The lower strength and elongation might have been due to lower structural gelatin levels present in fish gelatin films. The addition of cross-linkers had little effect on tensile properties and melting temperatures of fish gelatin films. Pollock gelatin films had the lowest water vapor and oxygen permeability values, whereas mammalian gelatin films had the highest permeability values. Cross-linking resulted in lower water vapor permeability for salmon gelatin films and higher oxygen permeability for pollock gelatin films. However, all fish gelatin films had better water vapor and oxygen barrier properties than mammalian gelatin films. Also, fish gelatin films degraded faster than mammalian gelatin films. 相似文献
958.
Meera Moydeen Abdul Hameed Syed Ali Padusha Mohamed Khan Badr M. Thamer Nirmala Rajkumar Hany El-Hamshary Mohamed El-Newehy 《先进技术聚合物》2023,34(1):6-23
Electrospinning procedures such as blend electrospinning, coaxial electrospinning, and emulsion electrospinning have been used for the fabrication of electrospun nanofibers (ENFs) for biomedical applications. These ENFs are attracted great interest especially in drug delivery applications due to their small size, high surface area-to-volume, and porosity. The aim of this review is to focus on the controlled release mechanism among the different electrospinning methods, and the selectivity of hydrophilic, water-soluble polymers as a carrier for drug. The mechanism for the drug delivery depends mainly on the method of drug loading, polymeric interactions, and the nature of polymer swelling, erosion, or degradation. This review compressed on the literature survey about the fabrication of nanofibers by different electrospinning methods, factors affecting the nanofiber morphologies, selectivity of polymeric blends for successful controlled release behavior, and the mechanism involved in the drug release steps. 相似文献
959.
Shukor MY Masdor N Baharom NA Jamal JA Abdullah MP Shamaan NA Syed MA 《Applied biochemistry and biotechnology》2008,144(3):283-291
A heavy-metal assay has been developed using bromelain, a protease. The enzyme is assayed using casein as a substrate with
Coomassie dye to track completion of hydrolysis of casein. In the absence of inhibitors, casein is hydrolysed to completion,
and the solution is brown. In the presence of metal ions such as Hg2+ and Cu2+, the hydrolysis of casein is inhibited, and the solution remains blue. Exclusion of sulfhydryl protective agent and ethylenediaminetetraacetic
in the original assay improved sensitivity to heavy metals several fold. The assay is sensitive to Hg2+ and Cu2+, exhibiting a dose–response curve with an IC50 of 0.15 mg l−1 for Hg2+ and a one-phase binding curve with an IC50 of 0.23 mg l−1 for Cu2+. The IC50 value for Hg2+ is found to be lower to several other assays such as immobilized urease and papain assay, whilst the IC50 value for Cu2+ is lower than immobilized urease, 15-min Microtox™, and rainbow trout. 相似文献
960.
Shukor MY Habib SH Rahman MF Jirangon H Abdullah MP Shamaan NA Syed MA 《Applied biochemistry and biotechnology》2008,149(1):33-43
A molybdate-reducing bacterium has been locally isolated. The bacterium reduces molybdate or Mo6+ to molybdenum blue (molybdate oxidation states of between 5+ and 6+). Different carbon sources such as acetate, formate,
glycerol, citric acid, lactose, fructose, glucose, mannitol, tartarate, maltose, sucrose, and starch were used at an initial
concentration of 0.2% (w/v) in low phosphate media to study their effect on the molybdate reduction efficiency of bacterium. All of the carbon sources
supported cellular growth, but only sucrose, maltose, glucose, and glycerol (in decreasing order) supported molybdate reduction
after 24 h of incubation. Optimum concentration of sucrose for molybdate reduction is 1.0% (w/v) after 24 h of static incubation. Ammonium sulfate, ammonium chloride, valine, OH-proline, glutamic acid, and alanine (in
the order of decreasing efficiency) supported molybdate reduction with ammonium sulfate giving the highest amount of molybdenum
blue after 24 h of incubation at 0.3% (w/v). The optimum molybdate concentration that supports molybdate reduction is between 15 and 25 mM. Molybdate reduction is optimum
at 35 °C. Phosphate at concentrations higher than 5 mM strongly inhibits molybdate reduction. The molybdenum blue produced
from cellular reduction exhibits a unique absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. The
isolate was tentatively identified as Serratia marcescens Strain Dr.Y6 based on carbon utilization profiles using Biolog GN plates and partial 16s rDNA molecular phylogeny. 相似文献