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51.
Sol-gel synthesized nickel oxide (NiO) film deposited onto indium tin oxide (ITO) coated glass plate has been utilized for the development of sensitive and stable DNA biosensor and demonstrated for diagnosis of visceral leishmaniasis also known as Kala-azar. Leishmania specific sensor is developed by immobilizing 23mer DNA sequence (oligonucleotide) identified from 18S rRNA gene sequences from Leishmania donovani. Characterization studies like X-Ray Diffraction and Scanning Electron Microscopy revealed the formation of nano-structured NiO, while immobilization of single strand (ss)-DNA of Leishmania was supported by UV-visible, Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy techniques. Response studies of ss-DNA/NiO/ITO bioelectrode are carried out using differential pulsed voltammetry in presence of methylene blue redox dye as a redox mediator. A linear response is obtained in the wide concentration range of 2 pg ml(-1) to 2 μg ml(-1) of complementary target genomic DNA (disease DNA) within the variation of 10% for 5 sets of studies. The observed results hold promise not only for diagnosis of Kala-azar patients but also hold enormous potential of the nano-NiO based probe for development of stable and sensitive biosensors.  相似文献   
52.
An efficient Zn(II)-catalyzed intermolecular double hydroamination of 1,3-enynes with aryl hydrazines, for the synthesis of pyrazolines, has been discussed.  相似文献   
53.
An experimental study of heat transfer during quenching of a cylindrical stainless steel test specimen has been performed. A subcooled water jet is directed onto the upward facing flat face of the cylinder. The test specimen is heated to an initial temperature slightly above 900 °C and then quenched. The resulting boiling curves and heat transfer distributions are presented for impingement velocities of 2.85 and 6.4 m/s (Re = 7900 and 18,900). High-speed imaging shows that three distinct regions on the quenched surface can be identified: an expanding circular wetted region surrounding the impinging point, annular transition zone just outside the wetting front, and a unwetted region outside this zone. The free-surface of the liquid in the wetted region is smooth in the nucleate and transition boiling regimes. The annular transition zone or the wetting front region outside the wetted region is characterized by a highly disturbed liquid-gas interface, which can be attributed to intense vapor generation. At the outer edge of the transition zone, the liquid is deflected away from the surface. The velocity of the wetting front significantly increases with the jet impact velocity, which indicates that the wetting front position is governed by the ability of the flowing liquid to transport the bubbles radially outwards from the wetted region.  相似文献   
54.
Summary In this paper we study the spectral brightness of the radiation emitted by electrons moving in longitudinal wiggler and solenoidal magnetic field. The analysis is based on the evaluation of the Lienard-Wiechert potential retaining the condition of far-field limit. Some features of a longitudinal wiggler are presented and compared with the results relevant to the brightness of the helical wiggler and the solenoidal magnetic field employed in gyrotron-type devices.  相似文献   
55.
This paper presents an investigation of the enhancement of self focusing of high frequency EM waves in a compensated degenerate magnetoactive solid state plasma. The nonlinearity in the dielectric constant responsible for self focusing arises due to nonuniform heating and consequent redistribution Of carriers. A rigorous kinetic treatment valid beyond the perturbation limit has been presented assuming the carrier relaxation time to be energy dependent. The results show that the self-focusing of extraordinary waves is enhanced while that of ordinary waves is reduced with ωcω increasing. However the focusing of extraordinary waves is not possible when ωc > ω. The effect of degeneracy is also found to enhance the self-focusing of the waves while that of the enhanced absorption is to suppress the self-focusing process.  相似文献   
56.
Complexation of 3-nitroso-4-hydroxy-5, 6-benzocoumarin with iron (II) is used to detect iron in presence of various ions present in the scheme of semi-micro qualitative analysis. The method finds application in detection of iron in alloys, inorganic salts and various pharmaceutical products.  相似文献   
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Electroluminescent CdS : Sm and CdS : Cu, Sm phosphors have been prepared and their EL characteristics are investigated. The brightness waves of these phosphors were measured at a sinusoidal alternating voltages with a frequency of 500 Hz, 1 kHz, 2 kHz and 5 kHz. One primary and one secondary peak have been observed in each half period of the applied sinusoidal field. Time averaged EL brightness has been found to follow the Alfrey-Taylor relationB= =B 0 exp (–b/V 1/2) over a wide range of frequencies. Variation of the constants of this relation with frequency of the applied field have been studied. Variation of current across the EL cell with the applied voltage has also been investigated. The EL emission spectra show peaks at 600 and 650 nm in CdS : Sm phosphor whereas in the case of CdS : Cu, Sm phosphor the emission peak occurs at 600 nm. The observed results have been interpreted in terms of acceleration collision theory of the electroluminescence.One of the authors (RKT) expresses his gratitude to the University Grants Commission, New Delhi, for a fellowship and the Principal, S. D. J. Post Graduate College, Chandesar Azamgarh, for study leave.  相似文献   
60.
Summary Let <InlineEquation ID=IE"1"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"2"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"3"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"4"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"5"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"6"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"7"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"8"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"9"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"10"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"11"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"12"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"13"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"14"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"15"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"16"><EquationSource Format="TEX"><![CDATA[$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>L$ be a compactly generated multiplicative lattice with 1 compact in which every finite product of compact elements is compact and $u\in L$ denote a radical element. We generalize the concepts, such as, Baer element, closed element etc. Using these concepts, we generalize many results proved by~D.~D. Anderson, C. Jayaram and others. In this paper we provide the modified definition for regular lattices and find their characterizations. Also we give abstract versions of many known results of ideal theory of commutative rings. Some of the important results are: \bigskip {\sc Result 1.} In $S$, suppose a finite product of compact elements is compact. Then the following statements on $S$ are equivalent. \begin{itemize} \item $S$ is a regular lattice. \item Every semiprimary element of $S$ is maximal. \item Every semiprimary element of $S$ is minimal prime. \item Every primary element of $S$ is minimal prime. \item Every primary element of $S$ is maximal. \item Every prime element of $S$ is maximal. \item Every prime element of $S$ is minimal prime. \end{itemize} \bigskip {\sc Result 2.} Let $S$ be a compactly generated multiplicative lattice (not necessarily, 1 compact). Then $S$ is a sublattice of a regular lattice iff $0=\sqrt 0$ in $S$.  相似文献   
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