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排序方式: 共有269条查询结果,搜索用时 250 毫秒
261.
Sherin Fahainy Nasir 《Supramolecular chemistry》2013,25(5-6):329-337
Assembly of viral protein coats is crucial to the protection of internal genetic cargo and is necessary for proper infection. Understanding the conditions for maintaining these supramolecular assemblies is of value for engineering-effective virus-based materials and related technologies. In this study, we examine the stability of the filamentous bacteriophage, fd-tet, in a variety of solvent and temperature conditions. On the basis of these results, we advise amenable reaction environments for modification of fd-tet. In particular, assessment of the temperature stability indicates that practical use of these viruses as reaction substrates is best performed at moderate temperatures, since loss in infectivity was found to occur within only 1-h incubation over 37°C. In addition, these findings reveal additional loss of infectivity after exposure to conditions near pH 4.5 which may be attributable to changes in the effective charge of the p8 major coat protein. 相似文献
262.
A highly selective synthesis of 2-aryl-1-arylmethyl-1H-1,3-benzimidazoles from the reaction of o-phenylenediamine and aromatic aldehydes in the presence of sulfuric acid {[3-(3-silicapropyl)sulfanyl]propyl}ester(SASPSPE) in water and at 80℃in good to excellent yields. 相似文献
263.
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
264.
An approximate solution for the nuclear Hulthén plus atomic Hulthén potentials is constructed by solving the associated Volterra integral equation by series substitution method. Within the framework of supersymmetry-inspired factorisation method, this solution is exploited to construct higher partial wave interactions. The merit of our approach is examined by computing elastic scattering phases of the \(\alpha {-}\alpha \) system by the judicious use of phase function method. Reasonable agreements in phase shifts are obtained with standard data. 相似文献
265.
Nasir?Ganikhodjaev Muzaffar?RahmatullaevEmail author Mohd?Hirzie?Bin?Mohd?Rodzhan 《Mathematical Physics, Analysis and Geometry》2018,21(1):2
For Ising model on the Cayley tree of order five and six we present new weakly periodic (non-periodic) Gibbs measures corresponding to normal subgroups of indices two in the group representation of the Cayley tree. 相似文献
266.
Nasir M. Ahmad Frank Heatley David Britton Peter A. Lovell 《Macromolecular Symposia》1999,143(1):231-241
Chain transfer to polymer in emulsion polymerizations of acrylate monomers and vinyl acetate has been studied using 13C NMR spectroscopy to elucidate the chemistry by which chain transfer occurs and to quantify the mol% branches resulting from the reaction. In emulsion polymerizations of n-butyl acrylate, ethyl acrylate and methyl acrylate, chain transfer to polymer proceeds via abstraction of hydrogen atoms from backbone tertiary C-H bonds and typically gives rise to 2-4 mol% branches in the polymers obtained at complete conversion, the level of branching increasing with reaction temperature. For these acrylates, there is no evidence for a significant difference between the extent of chain transfer to polymer. In emulsion polymerizations of vinyl acetate, chain transfer to polymer proceeds mainly via H-abstraction from methyl side-groups, though there is a small contribution from abstraction at backbone tertiary C-H bonds. The levels of branching that result are substantially lower than in acrylate emulsion polymerizations, typically being in the range 0.6-0.8 mol% in the polymers obtained at complete conversion. The level of branching increases with temperature and as the degree of monomer starving (and hence instantaneous conversion) increases. Emulsion copolymerization of vinyl acetate with a small amount (5-20 wt%) of n-butyl acrylate gives rise to a significant increase in the level of branching (to values around 1.3-1.6 mol%), which results predominantly from H-abstraction of backbone tertiary C-H bonds in n-butyl acrylate repeat units by propagating radicals with vinyl acetate end units. 相似文献
267.
Ayesha Samreen Muhammad Sudais Ali Muhammad Huzaifa Nasir Ali Bilal Hassan Fazl Ullah Shahid Ali Nor Anisa Arifin 《Chemical record (New York, N.Y.)》2024,24(1):e202300247
The high-temperature solid oxide fuel cells (SOFCs) are the most efficient and green conversion technology for electricity generation from hydrogen-based fuel as compared to conventional thermal power plants. Many efforts have been made to reduce the high operating temperature (>800 °C) to intermediate/low operating temperature (400 °C<T<800 °C) in SOFCs in order to extend their life span, thermal compatibility, cost-effectiveness, and ease of fabrication. However, the major challenges in developing cathode materials for low/intermediate temperature SOFCs include structural stability, catalytic activity for oxygen adsorption and reduction, and tolerance against contaminants such as chromium, boron, and sulfur. This research aims to provide an updated review of the perovskite-based state-of-the-art cathode materials LaSrMnO3 (LSM) and LaSrCOFeO3 (LSCF), as well as the recent trending Ruddlesden-Popper phase (RP) and double perovskite-structured materials SOFCs technology. Our review highlights various strategies such as surface modification, codoping, infiltration/impregnation, and composites with fluorite phases to address the challenges related to LSM/LSCF-based electrode materials and improve their electrocatalytic activity. Moreover, this study also offers insight into the electrochemical performance of the double perovskite oxides and Ruddlesden-Popper phase materials as cathodes for SOFCs. 相似文献
268.
Revathy Deivasigamani Nur Nasyifa Mohd Maidin Nur Shahira Abdul Nasir Abdullah Abdulhameed Aminuddin Bin Ahmad Kayani Mohd Ambri Mohamed Muhamad Ramdzan Buyong 《Electrophoresis》2023,44(5-6):573-620
Dielectrophoresis (DEP) bioparticle research has progressed from micro to nano levels. It has proven to be a promising and powerful cell manipulation method with an accurate, quick, inexpensive, and label-free technique for therapeutic purposes. DEP, an electrokinetic phenomenon, induces particle movement as a result of polarization effects in a nonuniform electrical field. This review focuses on current research in the biomedical field that demonstrates a practical approach to DEP in terms of cell separation, trapping, discrimination, and enrichment under the influence of the conductive medium in correlation with bioparticle viability. The current review aims to provide readers with an in-depth knowledge of the fundamental theory and principles of the DEP technique, which is influenced by conductive medium and to identify and demonstrate the biomedical application areas. The high conductivity of physiological fluids presents obstacles and opportunities, followed by bioparticle viability in an electric field elaborated in detail. Finally, the drawbacks of DEP-based systems and the outlook for the future are addressed. This article will aid in advancing technology by bridging the gap between bioscience and engineering. We hope the insights presented in this review will improve cell suspension medium and promote DEP-viable bioparticle manipulation for health-care diagnostics and therapeutics. 相似文献
269.