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151.
S. D. Bajpai 《Proceedings Mathematical Sciences》1969,70(2):99-101
In this paper we have employed Meijer’s G-function to solve a problem of the temperature in a nonhomogeneous bar and shown how Meijer’s G-function may be found useful in solving many problems of applied mathematics. 相似文献
152.
153.
Variable constant time delay adjustable by 20% over a bandwidth of 300 MHz at X-band has been theoretically obtained using a single delay line consisting of two ground planes. This has been achieved by rotating the direction of the applied DC magnetic field in the forward volume wave to the backward volume wave plane and adjusting the magnitude. Electronically variable constant delay lines have potential application in broadband phased array antennas and microwave signal processing. 相似文献
154.
S.N. Bajpai 《Journal of magnetism and magnetic materials》1985,50(1):59-63
An investigation of the effect of the direction of a dc biasing field on the magnetostatic volume wave delays in YIG sandwiched between two ground planes has been made. Specifically, the magnetic field has been assumed to be arbitrary in three planes: (a) forward volume wave to backward volume plane; (b) forward volume wave to surface wave plane; (c) backward volume wave to surface wave plane. A general dispersion relation has been derived. The numerical results indicate that delays can be controlled by the direction of the dc magnetic field. The effect of the thickness of the dielectric on the delay characteristics of magnetostatic backward volume waves has also been studied. The present study shows that a suitable filter can be designed, whose bandwidth may be varied by rotating the direction of the magnetic field. 相似文献
155.
In this work, calcium alginate hydrogels have been prepared by a new technique, called ‘diffusion through dialysis tube’ (DTDT) which involved transfer of crosslinking ions into alginate solution via a dialysis tube with a molecular weight cutoff of 8 k Da. The various hydrogels, prepared with varying degree of crosslinking, were characterized by FTIR, XRD and TG analysis. We also investigated their dynamic water absorbency in phosphate buffer saline (PBS) of pH 7.4 and the data were interpreted in terms of various kinetic models. The equilibrium water uptake data was used to determine network parameters of hydrogels. Finally, the stability and water absorbency of these hydrogels were enhanced to a desired level by using crosslinker solutions, composed of Ba++/Ca ++and Zn++ / Ca++ ions. 相似文献
156.
A highly efficient, green as well as atom economical protocol for the synthesis of substituted spirooxindoles from m-ZrO2 NPs catalyzed multicomponent reaction of isatin derivatives with ethyl cyanoacetate and 1,3-dicarbonyl compounds in a ball mill has been established. Because of the simple and readily available starting materials, easy operation, and high bioactivity of substituted spirooxindoles, this strategy can be broadly applied to medicinal chemistry. The recyclability of the m-ZrO2 Nps catalyst is another emphasis of proposed methodology. 相似文献
157.
We show that the limit of integrals along slices of a high dimensional sphere is a Gaussian integral on a corresponding finite-codimension affine subspace in infinite dimensions. 相似文献
158.
Shi‐Qiang Wang Soumya Mukherjee Ewa Patyk‐Ka
mierczak Shaza Darwish Alankriti Bajpai Qing‐Yuan Yang Michael J. Zaworotko 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(20):6702-6706
Purification of the C8 aromatics (xylenes and ethylbenzene) is particularly challenging because of their similar physical properties. It is also relevant because of their industrial utility. Physisorptive separation of C8 aromatics has long been suggested as an energy efficient solution but no physisorbent has yet combined high selectivity (>5) with high adsorption capacity (>50 wt %). Now a counterintuitive approach to the adsorptive separation of o‐xylene from other C8 aromatics involves the study of a known nonporous layered material, [Co(bipy)2(NCS)2]n ( sql‐1‐Co‐NCS ), which can reversibly switch to C8 aromatics loaded phases with different switching pressures and kinetics, manifesting benchmark o‐xylene selectivity (SOX/EB≈60) and high saturation capacity (>80 wt %). Structural insight into the observed selectivity and capacity is gained by analysis of the crystal structures of C8 aromatics loaded phases. 相似文献
159.
Shi‐Qiang Wang Soumya Mukherjee Ewa Patyk‐Ka
mierczak Shaza Darwish Alankriti Bajpai Qing‐Yuan Yang Michael J. Zaworotko 《Angewandte Chemie (International ed. in English)》2019,58(20):6630-6634
Purification of the C8 aromatics (xylenes and ethylbenzene) is particularly challenging because of their similar physical properties. It is also relevant because of their industrial utility. Physisorptive separation of C8 aromatics has long been suggested as an energy efficient solution but no physisorbent has yet combined high selectivity (>5) with high adsorption capacity (>50 wt %). Now a counterintuitive approach to the adsorptive separation of o‐xylene from other C8 aromatics involves the study of a known nonporous layered material, [Co(bipy)2(NCS)2]n ( sql‐1‐Co‐NCS ), which can reversibly switch to C8 aromatics loaded phases with different switching pressures and kinetics, manifesting benchmark o‐xylene selectivity (SOX/EB≈60) and high saturation capacity (>80 wt %). Structural insight into the observed selectivity and capacity is gained by analysis of the crystal structures of C8 aromatics loaded phases. 相似文献
160.
Van Wijk R Van Wijk EP Bajpai RP 《Journal of photochemistry and photobiology. B, Biology》2006,84(1):46-55
Spontaneous photon emission from 30 sites on the skin of a live human subject is measured at different times and on different days. Signals from three representative sites of low, intermediate and high intensities are selected for further analysis. Fluctuations in these signals are measured by the probabilities of detecting different numbers of photons in a bin. The probabilities have non-classical features and are well described by the signal in a quantum squeezed state of photons. Measurements with bins of three sizes yield same values of three parameters of the squeezed state. A procedure for making correction due to background noise is developed. The correction changes the parameters of the quantum state. The new state appears more like a coherent state of photons. 相似文献