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81.
A first novel synthetic utility of catalytic sodium nitrite in combination with aqueous HBr, for bromo decarboxylation of α,β-unsaturated carboxylic acid is described. α,β-Unsaturated carboxylic acid compounds successfully converted into corresponding bromo compounds. The advantages of this protocol are shorter reaction time and moderate to good yields. 相似文献
82.
Vikas M. Nadkarni 《Journal of Chemical Sciences》1983,92(6):623-637
The diversity of applications, versatality of property modifications, motivations for development and commercial significance
of polymer alloys are reviewed with reference to commercially available materials. The key steps and scientific considerations
central to the development of thermoplastic blend systems are discussed. The scientific considerations in developing the technology,
such as thermodynamics of polymer-polymer miscibility, thermal and mechanical compatibility, phase diagram/morphology, interphase
adhesion, and kinetics of solidification are highlighted with the help of specific examples from practice. Specific areas
for research and development in polymer alloys in India are indicated emphasizing the need for an applied research bias.
Presented at the Symposium on ‘Polymer Science and Engineering’ during Annual Meeting of the Academy, Nainital October 1982. 相似文献
83.
Vikas Bist 《代数通讯》2013,41(6):1747-1761
By a right (left resp.) S2n-polynomial we mean a multilinear polynomial f(X1,…, Xt) over the ring of integers with noncommuting in-determinates Xisuch that for any prime ring R if f( X1,…, X t) is a PI of some nonzero right (left resp.) ideal of R, then R satisfies S2nthe standard identity of degree 2n. In this paper we prove the theorem:Let R be a prime ring, d a nonzero derivation of R, L a noncommutative Lie ideal of R and f(X1,…, Xt) a right or left S2n-polynomial. Suppose that f(d( u1)n1,…,d(ut)nt)=0 for all uiu,i[d] L, where n1,…,ntare fixed positive integers. Then R satisfies S2n+2. Also, the one-sided version of the theorem is given. 相似文献
84.
85.
Vikas Mishra Vijaya Lakshmi Nag Ritu Tandon Shally Awasthi 《Applied biochemistry and biotechnology》2010,160(8):2322-2331
Management of rotavirus diarrhoea cases and prevention of nosocomial infection require rapid diagnostic method at the patient
care level. Diagnostic tests currently available are not routinely used due to economic or sensitivity/specificity constraints.
Agarose-based sieving media and running conditions were modulated by using central composite design and response surface methodology
for screening and electropherotyping of rotaviruses. The electrophoretic resolution of rotavirus genome was calculated from
input parameters characterising the gel matrix structure and running conditions. Resolution of rotavirus genome was calculated
by densitometric analysis of the gel. The parameters at critical values were able to resolve 11 segmented rotavirus genome.
Better resolution and electropherotypic variation in 11 segmented double-stranded RNA genome of rotavirus was detected at
1.96% (w/v) agarose concentration, 0.073 mol l−1 ionic strength of Tris base–boric acid–ethylenediamine tetraacetic acid buffer (1.4×) and 4.31 h of electrophoresis at 4.6 V cm−1 electric field strength. Modified agarose gel electrophoresis can replace other methods as a simplified alternative for routine
detection of rotavirus where it is not in practice. 相似文献
86.
87.
Shilpa Raina Vikas Sharma Zahid Nabi Sheikh Navneet Kour Shashank K. Singh Ali Zari Talal A. Zari Hesham F. Alharby Khalid Rehman Hakeem 《Molecules (Basel, Switzerland)》2022,27(7)
The current study was conducted to examine the in vitro anticancer potential of Cordia dichotoma (bark, leaves, pulp and seed). The plant material was collected from UT of J&K and methodical bioassays were carried out on ten human cancer cell lines (Michigan Cancer Foundation-7 (MCF-7), M.D. Anderson-Metastatic Breast (MDA-MB-231), Neuroblastoma-2a (N2A), SH-SY5Y, U-251, HCT-116, SW-620, A-549, MIA PaCa-2, Panc-1) from five different origins (breast, CNS, colon, lung, pancreas) respectively. Methanolic extracts were produced and fractions were then obtained from the extracts and evaluated for cytotoxicity. Mechanistic assays, HPLC, and GCMS profiling were performed on the highest active fraction. The Sulforhodamine B (SRB) assay determined the in vitro cytotoxicity. The findings revealed that the bark portion had in vitro cytotoxicity against the A-549 human lung cancer cell line. To our knowledge, this is the first study to show that the plant’s bark has anticancer properties and induced chromatin condensation, confirmed cell death via ROS generation, and significantly decreased colony formation in A-549 cell line from lung origin in a dose-dependent manner. Furthermore, HPLC and GCMS investigations indicated the presence of a number of bioactive molecules such as gallic acid (144,969.86) uV*sec, caffeic acid (104.26) uV*sec, ferulic acid (472.87) uV*sec, vanillic acid (13,775.39) uV*sec, palmitic acid (18.34%), cis vaccenic acid (28.81%), etc. and one of the compounds was reported for the first time from the bark. As a result of its promising efficacy, it may become an essential cancer chemopreventive or chemotherapeutic medication for patients with lung carcinoma. 相似文献
88.
A new, simple and low cost voltammetric method for the determination of cefpirome in pharmaceutical preparations has been developed using multiwalled carbon nanotube modified glassy carbon electrode (MWCNT), which showed stable response with enhanced selectivity and sensitivity over the bare glassy carbon electrode. A multiwalled carbon nanotube (MWCNT) modified glassy carbon electrode (GCE) is used for the simultaneous determination of cefpirome by differential pulse voltammetry and square wave voltammetry. Results indicated that cathodic peak of cefpirome is greatly improved at MWCNT modified GC electrode as compared with the bare GC electrode showing excellent electrocatalytic activity towards cefpirome reduction. Linear calibration curves are obtained over the concentration range 100-600 μg mL(-1) in Britton Robinson buffer at pH 4.51 with limit of detection (LOD) and limit of quantification (LOQ) are 0.647 μg mL(-1) and 2.159 μg mL(-1) using SWV and 5.540 μg mL(-1) and 18.489 μg mL(-1) using DPV, respectively. The described method is rapid and can be successfully applied for the determination of cefpirome in bulk form and pharmaceutical formulations. 相似文献
89.
90.
The authors study how the simultaneous presence of short-range secondary and long-range tertiary interactions controls the folding and collapse behavior of a helical macromolecule. The secondary interactions stabilize the helical conformation of the chain, while the tertiary interactions govern its overall three-dimensional shape. The authors have carried out Monte Carlo simulations to study the effect of chain length on the folding and collapse behavior of the chain. They have calculated state diagrams for four chain lengths and found that the physics is very rich with a plethora of stable conformational states. In addition to the helix-coil and coil-globule transitions, their model describes the coupling between them which takes place at low temperatures. Under these conditions, their model predicts a cascade of continuous, conformational transitions between states with an increase in the strength of the tertiary interactions. During each transition the chain shrinks, i.e., collapses, in a rapid and specific manner. In addition, the number of the transitions increases with increasing chain length. They have also found that the low-temperature regions of the state diagram between the transition lines cannot be associated with specific structures of the chain, but rather, with ensembles of various configurations of the chain with similar characteristics. Based on these results the authors propose a mechanism for the folding and collapse of helical macromolecules which is further supported by the analysis of configurational, configurational, and thermodynamic properties of the chain. 相似文献