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排序方式: 共有384条查询结果,搜索用时 15 毫秒
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J. P. Dwivedi S. K. Shah P. C. Upadhyay N. K. Das Talukder 《International Journal of Mechanical Sciences》2002,44(7):1505-1519
A theoretical analysis of the springback of narrow rectangular strips of non-linear work-hardening material under torsional loading has been carried out. This theoretical analysis is supported by experimental results for rectangular mild steel strips of different thicknesses and lengths. Finally an analytical generalized expression relating angle of twist to twisting moment and residual angle of twist per unit length for rectangular strips under plastic torsion is obtained in non-dimensionalized form. A comparison between the results obtained for bars of non- linear and linear work-hardening materials loaded under torsion is also made. 相似文献
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Some substituted coumarins have been synthesized by von-Pechmann condensation using SnCl2 · 2H2O (10 mol %) as catalyst in ethanolic medium. The reactions are simple, easy in handling and environmentally benign. 相似文献
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Buffalo milk Cheddar cheese samples of different ages were analysed for compositional attributes (CA), ripening indices (RI) and Instron Textural Profile (ITP). All samples were compositionally alike, except for pH and salt-in-moisture (SM) contents. RI showed significant variations. CA and RI showed highly significant correlations within themselves and with each other, except for moisture with pH, SM with moisture, MNFS, Fat and FDM and Fat with MNFS. The ITPs of cheeses showed significant variations and had highly significant intercorrelations indicating their interdependence. CA (except moisture and MNFS) and RI showed a highly significant correlationship with ITPs. Moisture content showed a highly significant correlationship with all ITPs, except cohesiveness and springiness, where it was significant. MNFS content showed significant correlations only with hardness and brittleness. Stepwise regression analysis revealed that MI was the most predominant factor influencing cheese texture, followed by pH, SM, FDM and TVFA. Knowing Ca and RI, the textural properties of cheeses can be forecast through mathematical equations. Similarly the age of cheese can also be predicted if RI and/or textural properties are known. 相似文献
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A new multijet tuyere type gas distributor is examined for its operational characteristics and appropriateness for gas—solid fluidized bed systems. Tuyeres of different number of slits and slit widths are investigated and their pressure drop data are correlated in terms of tuyere gas velocity. The fluidization quality of silica sand beds of average particle diameter 451 μm is assessed in conjunction with such distributor plates. It is found that such tuyeres service a bed area nearly twice their own size. 相似文献
7.
Upadhyay J Joshi MJ Deshpande PP Sharma ML Navathe CP 《The Review of scientific instruments》2008,79(5):054701
In this paper, a ramp generator with programmable slope is presented. It consists of a high voltage step generator, followed by integrator. The capacitor and inductor in the integrator are designed such that they can be varied by a microcontroller. This circuit generates two bipolar ramps with fastest speed <1 ns and provides continuous speed variation from 6 to 30 ns for a ramp of 500 V. This is being developed as a part of automated streak camera for deflection of electron beam. 相似文献
8.
Development of a method employing reversed‐phase thin‐layer chromatography for establishing milk fat purity with respect to adulteration with vegetable oils 下载免费PDF全文
Neelam Upadhyay Anil Kumar Gopal Rathod Ankit Goyal Darshan Lal 《International Journal of Dairy Technology》2015,68(2):207-217
A systematic study was conducted using reversed‐phase thin‐layer chromatography wherein unsaponifiable matter of samples namely, pure cow and buffalo milk fats, vegetable oils (groundnut oil, soya bean oil and sunflower oil) and milk fats adulterated with vegetable oils (≥1%) were run along with the reference standards using two new solvent systems to detect adulteration in milk fat. The results of the study revealed that adulteration at even a 1% level could easily be detected using this rapid, reliable and reproducible method based on the presence of β‐sitosterol as a marker and some additional spots ascribable to their occurrence in vegetable oils only. 相似文献
9.
Khan Muzaffar Iqbal Upadhyay Trilok Chandra 《Journal of Low Temperature Physics》2021,203(5-6):401-418
Journal of Low Temperature Physics - Modified two-sublattice pseudospin lattice coupled-mode (PLCM) model Hamiltonian by adding third- and fourth-order anharmonic interactions, extra... 相似文献
10.
Maitreyi Upadhyay Suneet K. Awasthi Laxmi Shiveshwari S. N. Shukla S. P. Ojha 《Journal of Superconductivity and Novel Magnetism》2015,28(7):1937-1942
By studying temperature-dependent dispersion characteristics and group velocity of 1D ternary photonic crystal (TPC) composed of dielectric-superconductor-dielectric materials, a thermally tunable band-stop filter which is capable of stopping unique wavelength channels without causing any interference amongst equally spaced wavelength channels of full width at half maximum of 1 nm each as per the requirement of wavelength division multiplexing standards adopted by the International Telecommunication Union specifying channel spacing in terms of frequency (wavelength) is suggested. The proposed structure can efficiently work as a two-channel wavelength selective switch for wavelength division multiplexing (WDM)-based all-optical networks. This study also gives theoretical insight to design some new kind of optical memories and tunable buffers which holds data temporary and have potential applications in modern communication systems. 相似文献