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排序方式: 共有173条查询结果,搜索用时 15 毫秒
51.
Mukesh Kumar Ajay Kumar Surinder Singh R. K. Mahajan T. P. S. Walia 《Radiation measurements》2003,36(1-6):479-481
The concentration of uranium has been assessed in drinking water samples collected from different locations in Bathinda district, Punjab, India. The water samples are taken from hand pumps and tube wells. Uranium is determined using fission track technique. Uranium concentration in the water samples varies from 1.65±0.06 to 74.98±0.38 μg/l. These values are compared with safe limit values recommended for drinking water. Most of the water samples are found to have uranium concentration above the safe limit. Analysis of some heavy metals (Zn, Cd, Pb and Cu) in water is also done in order to see if some correlation exists between the concentration of uranium and these heavy metals. A weak positive correlation has been observed between the concentration of uranium and heavy metals of Pb, Cd and Cu. 相似文献
52.
A K Gupta Neeraj Khare D K Walia V S Tomar V N Ojha H C Pandey S K Bhatnagar Y K Jain 《Pramana》1990,35(2):L193-L198
DC SQUID structure consisting of two microbridges and a circular hole was patterned on BSCCO thick film using laser ablation
technique. Quantum interference effects on these patterned films were studied at fixed biasing current by applying changing
magnetic field. The SQUID with 100 μm × 70 μm microbridges showed noisy and irregular V-B behaviour whereas the SQUID containing
smaller microbridges showed better V-B characteristic. Temperature dependence of the I-V and V-B characteristics of the SQUID
is also reported. 相似文献
53.
This report investigates the effects of sample size on the separation and analysis of individual biological particles using microfluidic devices equipped with an orthogonal LIF detector. A detection limit of 17 +/- 1 molecules of fluorophore is obtained using this orthogonal LIF detector under a constant flow of fluorescein, which is a significant improvement over epifluorescence, the most common LIF detection scheme used with microfluidic devices. Mitochondria from rat liver tissue and cultured 143B osteosarcoma cells are used as model biological particles. Quantile-quantile (q-q) plots were used to investigate changes in the distributions. When the number of detected mitochondrial events became too large (>72 for rat liver and >98 for 143B mitochondria), oversampling occurs. Statistical overlap theory is used to suggest that the cause of oversampling is that separation power of the microfluidic device presented is not enough to adequately separate large numbers of individual mitochondrial events. Fortunately, q-q plots make it possible to identify and exclude these distributions from data analysis. Additionally, when the number of detected events became too small (<55 for rat liver and <81 for 143B mitochondria) there were not enough events to obtain a statistically relevant mobility distribution, but these distributions can be combined to obtain a statistically relevant electrophoretic mobility distribution. 相似文献
54.
An implantable manually-actuated microfabricated drug delivery device was demonstrated as a new approach for delivering therapeutic compounds to ocular tissue in acute in vitro, ex vivo, and in vivo studies. 相似文献
55.
Journal of Nanoparticle Research - Highly fluorescent nanoparticles, or quantum dots, have multiple applications in biology and biomedicine; however, in most cases, it is necessary to functionalize... 相似文献
56.
The synthesis of secondary amine by the photoalkylation of nitrobenzene with benzyl alcohol using a simple light source and sunlight is a challenging task. Herein, a one-pot cascade protocol is employed to synthesize secondary amine by the reaction between nitrobenzene and benzyl alcohol. The one-pot cascade protocol involves four reactions: (a) photocatalytic reduction of nitrobenzene to aniline, (b) photocatalytic oxidation of benzyl alcohol to benzaldehyde, (c) reaction between aniline and benzaldehyde to form imine, and (d) photocatalytic reduction of imine to a secondary amine. The cascade protocol to synthesize secondary amine is accomplished using Bi2MoO6 and Pd nanoparticles decorated Bi2MoO6 catalysts. The surface characteristics, oxidation states, and elemental compositions of the materials are characterized by several physicochemical characterization techniques. Optoelectronic and photoelectrochemical measurements are carried out to determine the bandgap, band edge potentials, photocurrents, charge carrier's separation, etc. An excellent yield of secondary amine is achieved with simple household white LED bulbs. The catalyst also exhibits similar or even better activity in sunlight. The structure-activity relationship is established using catalytic activity data, control reactions, physicochemical, optoelectronic characteristics, and scavenging studies. Bi2MoO6 and Pd nanoparticles decorated Bi2MoO6 exhibit excellent photostability and recyclability. The simple catalyst design with a sustainable and economical light source for the synthesis of useful secondary amine from the nitrobenzene and benzyl alcohol would attract the researchers to develop similar catalytic protocols for other industrially important chemicals. 相似文献
57.
58.
Synthesis,Spectroscopy, and Structures of Mono‐ and Dinuclear Copper(I) Halide Complexes with 1,3‐Imidazolidine‐2‐thiones 下载免费PDF全文
Simran Walia Supreet Kaur Jaspreet Kaur Amanpreet K. Sandhu Tarlok S. Lobana Geeta Hundal Jerry P. Jasinski 《无机化学与普通化学杂志》2015,641(10):1728-1736
Copper(I) halides with triphenyl phosphine and imidaozlidine‐2‐thiones (L ‐NMe, L ‐NEt, and L ‐NPh) in acetonitrile/methanol (or dichloromethane) yielded copper(I) mixed‐ligand complexes: mononuclear, namely, [CuCl(κ1‐S‐L ‐NMe)(PPh3)2] ( 1 ), [CuBr(κ1‐S‐L ‐NMe)(PPh3)2] ( 2 ), [CuBr(κ1‐S‐L ‐NEt)(PPh3)2] ( 5 ), [CuI(κ1‐S‐L ‐NEt)(PPh3)2] ( 6 ), [CuCl(κ1‐S‐L ‐NPh)(PPh3)2] ( 7 ), and [CuBr(κ1‐S‐L ‐NPh)(PPh3)2] ( 8 ), and dinuclear, [Cu2(κ1‐I)2(μ‐S‐L ‐NMe)2(PPh3)2] ( 3 ) and [Cu2(μ‐Cl)2(κ1‐S‐L ‐NEt)2(PPh3)2] ( 4 ). All complexes were characterized with analytical data, IR and NMR spectroscopy, and X‐ray crystallography. Complexes 2 – 4 , 7 , and 8 each formed crystals in the triclinic system with P$\bar{1}$ space group, whereas complexes 1 , 5 , and 6 crystallized in the monoclinic crystal system with space groups P21/c, C2/c, and P21/n, respectively. Complex 2 has shown two independent molecules, [(CuBr(κ1‐S‐L ‐NMe)(PPh3)2] and [CuBr(PPh3)2] in the unit cell. For X = Cl, the thio‐ligand bonded to metal as terminal in complex 4 , whereas for X = I it is sulfur‐bridged in complex 3 . 相似文献
59.
Kataria Rajat Jain Tarun Singh Neetu Kushwaha Jai Prakash Sharma Bandhana 《Journal of solution chemistry》2020,49(2):133-144
Journal of Solution Chemistry - Diaminomethanal (an organic compound), was examined as entrainer for dehydration of isopropanol?water system by extractive distillation. Isobaric... 相似文献
60.
This paper presents the Enhanced Raman scattering of a elliptical laser beam in a collisional plasma. We have considered the mechanism of non‐uniform heating of carriers along the wave‐front, which is important in collisional plasma. The nonlinearity arising through non‐uniform heating leads to redistribution of carriers, which modifies the background plasma density profile in a direction transverse to pump beam axis. This modification in density effects the incident laser beam, plasma wave and back‐scattered beam. Non‐linear differential equations for the beam width parameters of pump laser beam, plasma wave and back‐scattered beam are set up and solved numerically. Numerical results predict the effect of self‐focusing of waves on the back‐scattered beam (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献