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91.
Manirul Islam Paramita Mondal Anupam Singha Roy Kazi Tuhina 《Transition Metal Chemistry》2010,35(4):427-435
A poly(3,6-dibenzaldimino N-vinyl carbazole) Pd(II) complex has been synthesized and characterized by physicochemical and spectroscopic techniques. The complex was found to be highly active toward hydrogenation reactions of various organic substrates under atmospheric pressure at ambient temperature. A tentative reaction mechanism is proposed on the basis of kinetic studies and isolation of reactive intermediates. The catalyst shows good conversion rates, thermal stability and recyclability. 相似文献
92.
Maestrini A. Ward J.S. Javadi H. Tripon-Canseliet C. Gill J. Chattopadhyay G. Schlecht E. Mehdi I. 《Microwave and Wireless Components Letters, IEEE》2005,15(12):871-873
We report on the design and performance of a fix-tuned /spl times/2/spl times/3/spl times/3 frequency multiplier chain that covers 1.55-1.75THz. The chain is nominally pumped with 100mW at W-band. At 120K the measured output power is larger than 4/spl mu/W across the band with a peak power of 100/spl mu/W at 1.665THz. A similar chain operated at room temperature produced a peak power of 21/spl mu/W. These power levels now make it possible to deploy multipixel heterodyne imaging arrays in this frequency range. 相似文献
93.
The effect of additives and cure cyle parameters on pre and post irradiation annealing characteristics of CR-39 detectors has been investigated. Effect of pre and post irradiation annealing on bulk etch rate, sensitivity, track diameter and etching behaviour of various CR-39 detectors has been investigated. 相似文献
94.
Chintamani Mande Subha Chattopadhyay Prabodh C Deshmukh R Padma Pranawa C Deshmukh 《Pramana》1990,35(4):397-403
A new scale of electronegativity based on X-ray spectroscopic data was earlier presented by Mande and others for the elements3Li to54Xe. The present paper reports an extension of this scale carried out for most of the heavier elements lying between55Cs and92U. The present approach is based on the physical interpretation of electronegativity of an atom as the attractive electrostatic
force it exerts at a distance equal to its covalent radius. To estimate this force, experimental spectroscopic data have been
employed. The merits of such an approach have been pointed out recently by Mullay and may be of interest in the context of
the intimate relation found between electronegativity and superconducting transition temperature. 相似文献
95.
In this paper we report a new method of fabrication of surface tensionconfined microfluidic devices on glass. We have also
successfully carried out some well-known chemical reactions in these fluidic channels to demonstrate the usefulness of these
wall-less microchannels. The confined flow path of liquid was achieved on the basis of extreme differences in hydrophobic
and hydrophilic characters of the surface. The flow paths were fabricated by making parallel lines using permanent marker
pen ink or other polymer on glass surfaces. Two mirror image patterned glass plates were then sandwiched one on top of the
other, separated by a thin gap-created using a spacer. The aqueous liquid moves between the surfaces by capillary forces,
confined to the hydrophilic areas without wetting the hydrophobic lines, achieving liquid confinement without physical side-walls.
We have shown that the microfluidic devices designed in such a way can be very useful due to their simplicity and low fabrication
cost. More importantly, we have also demonstrated that the minimum requirement of such a working device is a hydrophilic line
surrounded by hydrophobic environment, two walls of which are constituted of air and the rest is made of a hydrophobic surface. 相似文献
96.
Leemans W.P. Schoenlein R.W. Volfbeyn P. Chin A.H. Glover T.E. Balling P. Zolotorev M. Kim K.-J. Chattopadhyay S. Shank C.V. 《Quantum Electronics, IEEE Journal of》1997,33(11):1925-1934
The interaction of relativistic electrons with terawatt femtosecond laser pulses is reviewed with emphasis on how the scattering process can be used as a source of ultrashort X-ray pulses and as a time-resolved diagnostic for measuring transverse and longitudinal phase space distributions of an electron beam with microns spatial and subpicosecond temporal resolution. Recent experimental results are presented in which 90° Thomson scattering was utilized to generate 300 fs duration pulses of X-rays with peak energy of 30 keV. It is shown that, through analysis of the scattered X-ray beam properties, transverse and longitudinal distributions of the electron beam can be obtained 相似文献
97.
98.
Rajarshi Roy Nilesh Mazumder Gundam Sandeep Kumar Hitesh Mamgain Uttam Kumar Ghorai Dipayan Sen Kalyan Kumar Chattopadhyay 《Journal of Raman spectroscopy : JRS》2016,47(7):845-851
To probe the intrinsic stress distribution in terms of spatial Raman shift (ω) and change in the phonon linewidth (Γ), here we analyze self‐assembled graphene oxide fibers (GOF) ‘Latin letters’ by confocal Raman spectroscopy. The self‐assembly of GOF ‘Latin letters’ has been explained through surface tension, π–π stacking, van der Waals interaction at the air–water interface and by systematic time‐dependent investigation using field emission scanning electron microscopy analysis. Intrinsic residual stress due to structural joints and bending is playing a distinct role affecting the E2g mode (G band) at and away from the physical interface of GOF segments with broadening of phonon linewidth, indicating prominent phonon softening. Linescan across an interface of the GOF ‘letters’ reveals Raman shift to lower wavenumber in all cases but more so in ‘Z’ fiber exhibiting a broader region. Furthermore, intrinsic stress homogeneity is observed for ‘G’ fiber distributed throughout its curvature with negligible shift corresponding to E2g mode vibration. This article demonstrates the significance of morphology in stress distribution across the self‐assembled and ‘smart‐integrable’ GOF ‘Latin letters’. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
99.
Manojit Chattopadhyay Subrata Kumar Mitra 《Computational & Mathematical Organization Theory》2017,23(4):451-474
Measuring performance of microfinance institutions (MFIs) is challenging as MFIs must achieve the twin objectives of outreach and sustainability. We propose a new measure to capture the performance of MFIs by placing their twin achievements in a 2 × 2 grid of a classification matrix. To make a dichotomous classification, MFIs that meet both their twin objectives are classified as ‘1’ and MFIs who could not meet their dual objectives simultaneously are designated as ‘0’. Six classifiers are applied to analyze the operating and financial characteristics of MFIs that can offer a predictive modeling solution in achieving their objectives and the results of the classifiers are comprehended using technique for order preference by similarity to ideal solution to identify an appropriate classifier based on ranking of measures of performance. Out of six classifiers applied in the study, kernel lab-support vector machines achieved highest accuracy and lowest classification error rate that discriminates the best achievement of the MFIs’ twin objective. MFIs can use both these steps to identify whether they are on the right path to attaining their multiple objectives from their operating characteristics. 相似文献
100.
Let G be a finite group G, K a field of characteristic p ≥ 17 and let U be the group of units in KG. We show that if the derived length of U does not exceed 4, then G must be abelian. 相似文献