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41.
Two isomeric Schiff bases, HL 1 = 1-[(2-dimethylamino-ethylimino)-methyl]-naphthalen-2-ol and HL 2 = 1-[(2-ethylamino-ethylimino)-methyl]-naphthalen-2-ol, have been used to prepare copper(II) complexes in presence of thiocyanate. HL 1 forms a mononuclear complex [Cu(L 1 )NCS] with terminal thiocyanate, whereas the isomeric Schiff base HL 2 , which is capable of hydrogen bonding, gives a dimeric complex, [Cu2 (L 2 ) 2(NCS)2], with double μ-1,1-NCS bridges. Both complexes are characterized by physico-chemical and spectroscopic methods as well as by single crystal X-ray diffraction studies. 相似文献
42.
Rajesh Chakraborty Sriparna Chatterjee Pabitra Chattopadhyay 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(3):1565-1570
Nanocomposite titanium-phosphate (TiP) of different sizes was synthesized using Triton X-100 (polyethylene glycol-p-isooctylphenyl ether) surfactant. The materials were characterized by FTIR and powdered X-ray diffraction (XRD). The structural and morphological details of the material were obtained by scanning electron microscopy (SEM) and transmission electron microscopy. The SEM study was followed by energy dispersive spectroscopic analysis for elemental analysis of the sample. The important peaks of the XRD spectra were analyzed to determine the probable composition of the material. The average size distribution of the particles was determined by dynamic light scattering method. Ion exchange capacity was measured for different metal ions with sizes of the TiP nanocomposite and size-dependent ion exchange property of the material was investigated thoroughly. The nanomaterial of the smallest size of around 43 nm was employed to separate carrier-free 137mBa from 137Cs in column chromatographic technique using 1.0 M HNO3 as eluting agent at pH 5. 相似文献
43.
Subhadip Chakraborty Rajib Saha Anupam Karmakar Sanatan Chattopadhyay 《Electroanalysis》2021,33(5):1185-1193
The present work deals with fabrication and characterization of the zinc oxide (ZnO) nanowire based novel two-electrode capacitive biosensors on flexible Polyethylene terephthalate (PET) substrates for accurate estimation of glucose by analyzing the fundamental dielectric nature of the relevant sample. The morphology and crystalline quality of grown nanowires are analyzed by using field-emission scanning electron microscope (FESEM) and X-ray diffractometer (XRD), respectively. Current and capacitance values of the device have been studied for ten different glucose concentrations relevant to the physiological standards. The analytical performance of the devices in terms of enzyme activity, reliability and flexibility has also been evaluated. 相似文献
44.
Abelev BI Aggarwal MM Ahammed Z Anderson BD Arkhipkin D Averichev GS Bai Y Balewski J Barannikova O Barnby LS Baudot J Baumgart S Belaga VV Bellingeri-Laurikainen A Bellwied R Benedosso F Betts RR Bhardwaj S Bhasin A Bhati AK Bichsel H Bielcik J Bielcikova J Bland LC Blyth SL Bombara M Bonner BE Botje M Bouchet J Brandin AV Bravar A Burton TP Bystersky M Cadman RV Cai XZ Caines H Calderón de la Barca Sánchez M Callner J Catu O Cebra D Chajecki Z Chaloupka P Chattopadhyay S Chen HF Chen JH 《Physical review letters》2007,99(11):112301
We present first measurements of the phi-meson elliptic flow (v2(pT)) and high-statistics pT distributions for different centralities from radical sNN=200 GeV Au+Au collisions at RHIC. In minimum bias collisions the v2 of the phi meson is consistent with the trend observed for mesons. The ratio of the yields of the Omega to those of the phi as a function of transverse momentum is consistent with a model based on the recombination of thermal s quarks up to pT approximately 4 GeV/c, but disagrees at higher momenta. The nuclear modification factor (R CP) of phi follows the trend observed in the K S 0 mesons rather than in Lambda baryons, supporting baryon-meson scaling. These data are consistent with phi mesons in central Au+Au collisions being created via coalescence of thermalized s quarks and the formation of a hot and dense matter with partonic collectivity at RHIC. 相似文献
45.
Gnanasekar Rani Sarnaik Jayula S. Joseph N. C. Kadwad V. B. Mathur Anupam 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(1):71-76
Journal of Radioanalytical and Nuclear Chemistry - We describe a simple, user friendly two-step radioimmunoassay (RIA) based on antibody coated tubes for the measurement of free triiodothyronine in... 相似文献
46.
Rules of Boron–Nitrogen Doping in Defect Graphene Sheets: A First‐Principles Investigation of Band‐Gap Tuning and Oxygen Reduction Reaction Catalysis Capabilities
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Introduction of defects and nitrogen doping are two of the most pursued methods to tailor the properties of graphene for better suitability to applications such as catalysis and energy conversion. Doping nitrogen atoms at defect sites of graphene and codoping them along with boron atoms can further increase the efficiency of such systems due to better stability of nitrogen at defect sites and stabilization provided by B?N bonding. Systematic exploration of the possible doping/codoping configurations reflecting defect regions of graphene presents a prevalent doping site for nitrogen‐rich BN clusters and they are also highly suitable for modulating (0.2–0.9 eV) the band gap of defect graphene. Such codoped systems perform significantly better than the platinum surface, undoped defect graphene, and the single nitrogen or boron atom doped defect graphene system for dioxygen adsorption. Significant stretching of the O?O bond indicates a lowering of the bond breakage barrier, which is advantageous for applications in the oxygen reduction reaction. 相似文献
47.
Saurav Goel Sara Hawi Gaurav Goel Vijay Kumar Thakur Anupam Agrawal Clare Hoskins Oliver Pearce Tanvir Hussain Hari M. Upadhyaya Graham Cross Asa H. Barber 《Materials Today Chemistry》2020
The world is witnessing tumultuous times as major economic powers including the US, UK, Russia, India, and most of Europe continue to be in a state of lockdown. The worst-hit sectors due to this lockdown are sales, production (manufacturing), transport (aerospace and automotive) and tourism. Lockdowns became necessary as a preventive measure to avoid the spread of the contagious and infectious “Coronavirus Disease 2019” (COVID-19). This newly identified disease is caused by a new strain of the virus being referred to as Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS CoV-2; formerly called 2019-nCoV). We review the current medical and manufacturing response to COVID-19, including advances in instrumentation, sensing, use of lasers, fumigation chambers and development of novel tools such as lab-on-the-chip using combinatorial additive and subtractive manufacturing techniques and use of molecular modelling and molecular docking in drug and vaccine discovery. We also offer perspectives on future considerations on climate change, outsourced versus indigenous manufacturing, automation, and antimicrobial resistance. Overall, this paper attempts to identify key areas where manufacturing can be employed to address societal challenges such as COVID-19. 相似文献
48.
Mukhopadhyay Anandamoy Chattopadhyay Souradip Barua Amlan K. 《Nonlinear dynamics》2020,100(2):1143-1172
Nonlinear Dynamics - We investigated an incompressible viscous liquid film flow over a rotating vertical cylinder of radius R and of infinite length rotating with a uniform angular velocity... 相似文献
49.
Vanadium redox flow battery (VRFB) is a promising technology for large-scale renewable energy storage. Design of ion-exchange membrane (IEM) with desired properties like low-cost, mechanically chemically stable, low vanadium ion permeability and high proton conductivity is one of the major challenges. Here, we report the design and synthesis of novel poly(tetrafluoroethylene)-zirconium phosphate (PTFE-ZrP) asymmetric IEM using a simple brush coating method. XRD results confirmed the presence of α-ZrP crystalline phase onto the top layer of the membrane. Excellent mechanical strength was observed with burst pressure of 3.22 × 105 N m?2. Oxidative stability of membrane in Fenton’s reagent was much better than Nafion-115. Vanadium ion (V4+) permeability of the membrane was more than three times lower than that of Nafion-115. Single-cell VRFB with PTFE-ZrP membrane showed ~80% energy efficiency below 30 mA cm?2. Very high columbic efficiency ~100% of VRFB with PTFE-ZrP membrane confirmed little contamination of electrolyte due to cross-mixing. 相似文献
50.
To exploit the parallelism of optics in data processing,a suitable number system and an efficient encoding/decoding scheme for handling the data are very essential.In the field of optical computing and parallel information processing,several number systems like binary,quaternary,octal,hexadecimal,etc.have been used for different arithmetic and algebraic operations.Here,we have proposed an all-optical conversion scheme from its binary to its other 2n radix based form with the help of terahertz optical asymmetric demultiplexer (TOAD) based tree-net architecture. 相似文献