检索结果-南通市图书馆

Science China Chemistry 2011年第12期54卷 1909-1919页

作者： VARUGHESE Sunil sinha shashi bhushan DESIRAJU Gautam R. Solid State and Structural Chemistry Unit Indian Institute of Science

Phenylboronic acids can exist, in principle, in three different conformers （syn, syn; syn, anti and anti, anti） with distinct energy profiles. In their native state, these compounds prefer the energetically favored syn, anti-conformation. In molecular complexes, however, the functionality exhibits conformational diversity. In this paper we report a series of co-crystals, with N-donor compounds, prepared by a design strategy involving the synthons based on the syn, syn-conformation of the boronic acid functionality. For this purpose, we employed compounds with the 1,2-diazo fragment （alprazolam, 1H-tetrazole, acetazolamide and benzotriazole）, 1,10-phenanthroline and 2,2＇-bipyridine for the co-crystallization experiments. However, our study shows that the mere presence of the 1,2-diazo fragment in the coformer does not guarantee the successful formation of co-crystals with a syn, syn-conformation of the boronic acid.

关键词： crystal engineering phenylboronic acid supramolecular synthon conformational flexibility

苯硼酸衍生物的晶体工程:用能量较高的syn,syn-构象设计共晶(英文)

在线全文

学校读者我要写书评

暂无评论

中国科学：化学 2012年第1期42卷 95-96页

作者： VARUGHESE Sunil sinha shashi bhushan DESIRAJU Gautam R olid State and Structural Chemistry Unit Indian Institute of Science

研苯硼酸衍生物有3种不同构象(syn,syn-;syn,anti-和anti,anti-构象),这3种构象能量非常不同.苯硼酸衍生物通常是采用能量最低的syn,anti-构象存在.然而在配合物中,苯硼酸衍生物展现了硼酸功能团的构象多样性.在本文中,我们采用syn,syn... 详细信息

研苯硼酸衍生物有3种不同构象(syn,syn-;syn,anti-和anti,anti-构象),这3种构象能量非常不同.苯硼酸衍生物通常是采用能量最低的syn,anti-构象存在.然而在配合物中,苯硼酸衍生物展现了硼酸功能团的构象多样性.在本文中,我们采用syn,syn-构象的硼酸衍生物作为结构单元,与含氮给体化合物反应,合成了一系列共晶配合物.采用的含氮给体化合物包括含1,2-重氮片段的化合物(阿普唑仑,1H-四唑,乙酰唑胺和苯并三唑)、邻菲罗啉和2,2′-联吡啶.结果表明,只有1,2-重氮片段不一定能与syn,syn-构象的硼酸及衍生物生成共晶.

关键词：晶体工程苯硼酸衍生物超分子结构单元构象的灵活性

New Chain Imputation Methods for Estimating Population Mean in the Presence of Missing Data Using Two Auxiliary Variables

在线全文

学校读者我要写书评

暂无评论

Communications in Mathematics and Statistics 2023年第2期11卷 325-340页

作者： shashi bhushan Abhay Pratap Pandey Department of Mathematics and Statistics Dr.Shakuntala Misra National Rehabilitation UniversityLucknowIndia Department of Statistics Ramanujan College University of DelhiNew DelhiIndia

This article deals with some new chain imputation methods by using two auxiliary variables under missing completely at random(MCAR)*** proposed generalized classes of chain imputation methods are tested from the viewpoint of optimality in terms of *** proposed imputation methods can be considered as an efficient extension to the work of Singh and Horn(Metrika 51:267-276,2000),Singh and Deo(Stat Pap 44:555-579,2003),Singh(Stat A J Theor Appl Stat 43(5):499-511,2009),Kadilar and Cingi(Commun Stat Theory Methods 37:2226-2236,2008)and Diana and Perri(Commun Stat Theory Methods 39:3245-3251,2010).The performance of the proposed chain imputation methods is investigated relative to the conventional chain-type imputation *** theoretical results are derived and comparative study is conducted and the results are found to be quite encouraging providing the improvement over the discussed work.

关键词： Missing data Imputation MCAR

Synthesis,characterization and application of Lagerstroemia speciosa embedded magnetic nanoparticle for Cr(Ⅵ)adsorption from aqueous solution

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2017年第5期29卷 283-293页

作者： Shalini Srivastava shashi bhushan Agrawal Monoj Kumar Mondal Department of Botany Institute of Science Banaras Hindu University Varanasi 221005 India Department of Chemical Engineering and Technology Indian Institute of Technology Banaras Hindu University Varanasi 221005 Uttar Pradesh India

Lagerstroemia speciosa bark（LB） embedded magnetic nanoparticles were prepared by co-precipitation of Fe2＋ and Fe3＋ salt solution with ammonia and LB for Cr（Ⅵ） removal from aqueous *** native LB,magnetic nanoparticle（MNP）,*** embedded magnetic nanoparticle（MNPLB） and Cr（Ⅵ） adsorbed MNPLB particles were characterized by SEM-EDX,TEM,BET-surface area,FT-IR,XRD and TGA *** analysis confirmed nearly spherical shape of MNP with an average diameter of 8.76 nm and the surface modification did not result in the phase change of MNP as established by XRD analysis,while led to the formation of secondary particles of MNPLB with diameter of 18.54 *** results revealed covalent binding between the hydroxyl group of MNP and carboxyl group of LB particles and further confirmed its physico-chemical nature favorable for Cr（Ⅵ） *** Cr（Ⅵ） adsorption on to MNPLB particle as an adsorbent was tested under different contact time,initial Cr（Ⅵ） concentration,adsorbent dose,initial pH,temperature and agitation *** results of the equilibrium and kinetics of adsorption were well described by Langmuir isotherm and pseudo-second-order model,*** thermodynamic parameters suggest spontaneous and endothermic nature of Cr（Ⅵ）adsorption onto *** maximum adsorption capacity for MNPLB was calculated to be 434.78 mg/g and these particles even after Cr（Ⅵ） adsorption were collected effortlessly from the aqueous solution by a *** desorption of Cr（Ⅵ）-adsorbed MNPLB was found to be more than 93.72%with spent MNPLB depicting eleven successive adsorption-desorption cycles.

关键词： Lagerstroemia speciosa Magnetic nanoparticles Co-precipitation Cr(Ⅵ) ions Adsorption capacity

Histochemical pattern of gastrocnemius muscle in fluoride toxicity syndrome

在线全文

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2010年第2期3卷 136-140页

作者： shashi A bhushan B Bhardwaj M Department of Zoology Punjabi University

Objective:To evaluate the effect of sodium fluoride(NaF) on cytochemical distribution of proteins,DNA,and RNA in the gastrocnemius muscle of rat in experimental ***: Young Sprague Dawley albino rats were administered with NaF at 30,45,and 75 mg/kg bw/ day subcutaneously for 15 and 30 days,*** control animals were given the vehicle(1cc deionized double distilled water/kg bw/day).Results:In the first phase of 15 days experimentation,the gastrocnemius muscle of rats intoxicated with NaF at 30,45,and 75 mg /kg bw/ day showed decline in proteins including a amino acids as compared to control. In the second phase of 30 days experimentation,the muscle fibers of rat showed elevation in sarcolemmal and sarcoplasmic proteins in 30 mg NaF dose group,and angulated fibers exhibited increase in sarcolemmal proteins in 45 mg NaF *** marginal regions of angular and rim fibers showed deeply stained rings of sarcoplasmic proteins whereas the split fibers were faindy stained in rats treated with NaF at 75 mg/kg bw/day for 30 *** rats treated with NaF at 30 mg/kg bw/day for 15 days,the hypertrophied peripheral muscle fibers contained more DNA,however the atrophied fibers had more *** 45 mg NaF group,RNA was located in sarcolemmal regions,while DNA content decreased as compared to *** 75 mg NaF group,the muscle fibers had dark and light staining regions of DNA and *** the 30 days of experimentation,the DNA level decreased whereas RNA content increased in the gastrocnemius muscle fibers of the rat treated with NaF at 30 mg/kg bw/*** treatment group with NaF at 45 mg/kg bw/day,the RNA content slighdy declined in comparison to control,in all treatments for 15 days as well as in treatment group with NaF at 30 mg/kg bw/day for 30 days whereas the amount of DNA slightly increased as compared to treatment group with NaF at 75 mg/kg bw/day for 15 *** highest dose group revealed elevated amount of RNA whereas DNA content remained stable.C

关键词： Albino rats DNA Gastrocnemius muscle Proteins RNA Sodium fluoride

Transient peristaltic diffusion of nanofluids: A model of micropumps in medical engineering

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2018年第6期30卷 1001-1011页

作者： Dharmendra Tripathi shashi bhushan O.Anwar Bég Noreen Sher Akbar Department of Science and Humanities National Institute of TechnologyUttarakhand–246174 India Department of Mechanical Engineering Manipal University Department of Aeronautical and Mechanical Engineering University of Salford DBS & H CEME National University of Sciences and TechnologyIslamabad Pakistan

Peristaltic micro-pumps offer an excellent mechanism for delivery of a variety of medicines including drugs, corneal solutions etc. The surge in deployment of nanoparticles in medicine has provided new potential for such pumps. In light of this we investigate the time-dependent peristaltic flow of nanofluids with diffusive effects through a finite non-uniform channel, this geometry being more representative of real micro-pumps. Creeping flow is taken into account(inertial forces are small compared with viscous forces) i.e., Reynolds number is low(Re< 1) and wavelength is also taken to be very large. The Buongiorno formulation for nanofluids is employed with an Oberbeck-Boussinesq approximation. Closed-form solutions are developed for the non-dimensional governing equations subject to physically realistic boundary conditions. Mathematica symbolic software is employed to evaluate the evolution of nanoparticle fraction, temperature, axial velocity, transverse velocity and pressure difference distribution along the length of the pump channel with variation in thermal Grashof number, basic-density(species i.e., mass) Grashof number, Brownian motion parameter and thermophoresis parameter.

关键词： Unsteady flow peristaltic pumps nanofluids medical engineering diffusive process grashof number thermophoresis

Analytical approach to entropy generation and heat transfer in CNT-nanofluid dynamics through a ciliated porous medium

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2018年第2期30卷 296-306页

作者： Noreen Sher Akbar M.Shoaib Dharmendra Tripathi shashi bhushan O.Anwar Bég DBS&H CEME National University of Sciences and Technology School of Natural Sciences National University of Sciences and Technology Department of Mechanical Engineering Manipal University Medical Energy and Propulsion Engineering Sciences Department of Aeronautical and Mechanical Engineering University of Salford

The transportation of biological and industrial nanofluids by natural propulsion like cilia movement and self-generated contraction-relaxation of flexible walls has significant applications in numerous emerging technologies. Inspired by multi-disciplinary progress and innovation in this direction, a thermo-fluid mechanical model is proposed to study the entropy generation and convective heat transfer of nanofluids fabricated by the dispersion of single-wall carbon nanotubes（SWCNT） nanoparticles in water as the base fluid. The regime studied comprises heat transfer and steady, viscous, incompressible flow, induced by metachronal wave propulsion due to beating cilia, through a cylindrical tube containing a sparse（i.e., high permeability） homogenous porous medium. The flow is of the creeping type and is restricted under the low Reynolds number and long wavelength approximations. Slip effects at the wall are incorporated and the generalized Darcy drag-force model is utilized to mimic porous media effects. Cilia boundary conditions for velocity components are employed to determine analytical solutions to the resulting non-dimensionalized boundary value problem. The influence of pertinent physical parameters on temperature, axial velocity, pressure rise and pressure gradient, entropy generation function, Bejan number and stream-line distributions are computed numerically. A comparative study between SWCNT-nanofluids and pure water is also computed. The computations demonstrate that axial flow is accelerated with increasing slip parameter and Darcy number and is greater for SWCNT-nanofluids than for pure water. Furthermore the size of the bolus for SWCNT-nanofluids is larger than that of the pure water. The study is applicable in designing and fabricating nanoscale and microfluidics devices, artificial cilia and biomimetic micro-pumps.

关键词： Metachronal wave single-wall carbon nanotubes (SWCNT) entropy generation porous medium cilia motion heat transfer Bejan number

Functional properties, phenolic constituents and antioxidant potential of industrial apple pomace for utilization as active food ingredient

在线全文

学校读者我要写书评

暂无评论

Food Science and Human Wellness 2015年第4期4卷 180-187页

作者： Shalika Ranaa Sakshi Gupta Ajay Rana shashi bhushan Academy of Scientific and Innovative Research CSIR-Institute of Himalayan Bioresource TechnologyPalampurHimachal Pradesh 176061India Division of Biotechnology CSIR-Institute of Himalayan Bioresource TechnologyPalampurHimachal Pradesh 176061India Division of Hill Area Tea Science CSIR-Institute of Himalayan Bioresource TechnologyPalampurHimachal Pradesh 176061India Nutritionist Vivekanand Medical InstitutePalampurHimachal Pradesh 176061India

Apple pomace is a waste biomass generated after apple fruit *** present investigation,efforts were made to comprehend influence of differently dried pomace on cell wall properties and phenolic *** drying techniques were employed to remove moisture content from fresh apple *** dietary fiber yield(74%)and array of functional properties such as density,water and oil holding capacity,swelling capacity and glucose dialysis retardation index(36.91%)was found better in freeze dried *** higher total phenolics(5.78±0.08 mg GAE/g dry weight)content was also recorded in freeze dried fraction followed by oven and sun *** 50%aqueous acetone was found as more efficient solvent for extraction of phenolic ***-HPLC analysis has revealed presence of quercetin,phloridzin and phloretin as major ***,it is evident from the results that pomace generated at industrial scale can be utilized as a source of dietary food ingredient.

关键词： Dietary fiber Drying Apple pomace Polyphenols Antioxidant

A multiwavelength view of a classical T Tauri star CV Cha

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2019年第1期19卷 75-86页

作者： Jeewan Chandra Pandey Subhajeet Karmakar Arti Joshi Saurabh Sharma shashi bhushan Pandey Anil Kumar Pandey Aryabhatta Research Institute of Observational Sciences (ARIES)

Using long-term optical, ultraviolet(UV) and X-ray data, we present a study of a classical T Tauri star CV Cha. The V-band light curve obtained from the All Sky Automated Survey(ASAS) shows short as well as long-term variability. The short-term variability could be due to rotational modulation of CV Cha. We derive the rotational period of 3.714 ± 0.001 d for CV Cha. UV light curves obtained from Swift also show the variations. X-ray light curves from XMM-Newton and Swift do not show any significant short as well as long-term variability. However, the light curve from Chandra appears to be variable, which could be due to the emergence of flaring activities. X-ray spectra from all observations are explained well by the single temperature plasma of 0.95 keV with X-ray luminosity of 1030.4erg s-1in the 0.5–7.5 keV energy band. It appears that variability in optical and UV bands could be due to the presence of both hot and cool spots on the surface, while X-ray emission is dominated by magnetic processes.

关键词： stars:activity stars:individual(CV Cha) stars:pre-main sequence stars:variable:T Tauri X-ray:stars

Cloud‐based video streaming services:Trends,challenges,and opportunities

在线全文

学校读者我要写书评

暂无评论

CAAI Transactions on Intelligence Technology 2024年第2期9卷 265-285页

作者： Tajinder Kumar Purushottam Sharma Jaswinder Tanwar Hisham Alsghier shashi bhushan Hesham Alhumyani Vivek Sharma Ahmed I.Alutaibi CSE Department JMIETIYamunanagarHaryanaIndia Department of Information Technology ASETAmity University Uttar PradeshNoidaIndia Tata Communications Limited New DelhiIndia Department of Information Technology College of Computer and Information SciencesMajmaah UniversityMajmaahSaudi Arabia Amity School of Engineering and Technology Amity UniversityPatnaBiharIndia Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityTaifSaudi Arabia Department of Computer Engineering College of Computer and Information SciencesMajmaah UniversityMajmaahSaudi Arabia

Cloud computing has drastically changed the delivery and consumption of live streaming *** designs,challenges,and possible uses of cloud computing for live streaming are studied.A comprehensive overview of the technical and business issues surrounding cloudbased live streaming is provided,including the benefits of cloud computing,the various live streaming architectures,and the challenges that live streaming service providers face in delivering high‐quality,real‐time *** different techniques used to improve the performance of video streaming,such as adaptive bit‐rate streaming,multicast distribution,and edge computing are discussed and the necessity of low‐latency and high‐quality video transmission in cloud‐based live streaming is *** such as improving user experience and live streaming service performance using cutting‐edge technology,like artificial intelligence and machine learning are *** addition,the legal and regulatory implications of cloud‐based live streaming,including issues with network neutrality,data privacy,and content moderation are *** future of cloud computing for live streaming is examined in the section that follows,and it looks at the most likely new developments in terms of trends and *** technology vendors,live streaming service providers,and regulators,the findings have major policy‐relevant *** on how stakeholders should address these concerns and take advantage of the potential presented by this rapidly evolving sector,as well as insights into the key challenges and opportunities associated with cloud‐based live streaming are provided.

关键词： cloud computing video analysis video coding