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排序方式: 共有1337条查询结果,搜索用时 15 毫秒
1.
Patel Sapna Kumar Dushyant Chaurasiya Nitesh Kumar Tripathi Shweta 《Semiconductors》2019,53(13):1797-1803
Semiconductors - In the present paper, analytical modeling of surface potential and drain current for hetero-dielectric double gate tunnel FET (HDG-TFET) has been done. The two dimensional (2D)... 相似文献
2.
Deepmala Gupta Arvind Kumar Dwivedi Madhu Tripathi 《Lakes & Reservoirs: Research and Management》2019,24(4):391-393
Knowledge of the length–weight relationships (LWRs) of fish is an important tool to understand fish body form, growth pattern, stock management and their conservation. The present study focused on investigating the length–weight relationships for five catfish species, Pachypterus atherinoides (Bloch, 1794), belonging to family Horabagridae; Batasio batasio (Hamilton, 1822) family Bagridae; Bagarius yarrelli (Sykes, 1839), family Gogangra viridescens (Hamilton, 1822); and Sisor rhabdophorus (Hamilton, 1822) belonging to family Sisoridae. Specimens were collected from the middle stretch of the Ganga River in India from November 2016 to May 2018. A total of 174 specimens of five fish species were collected, and their total lengths were measured to the nearest centimetre and the body weight to the nearest gram. The value of the parameter slope (b) of LWRs of the five species ranged from 2.86 (B. yarrelli) to 3.16 (G. viridescens), with a mean value of 2.99. The results of the present study documented the new maximum total length (TL) for P. atherinoides and S. rhabdophorus. The present study also provides the first reference regarding LWRs for S. rhabdophorus. 相似文献
3.
Eighteen compositions of MoO3-Te at 800 °C and seven of each of MoO3-Cd (at 500 °C) and MoO3-Sb (at 600 °C) were heat treated in vacuum-sealed quartz ampules. The phases of the heat-treated compositions were analyzed using x-ray diffraction (XRD) patterns. The interactions in the three systems are summarized. Three phases in equilibrium are (1) in the MnO3-Te system at 800 °C, Te, Mo4O11, TeMo4O13—(0<xMoO 3<0 889) and MoO3, Mo4O11, TeMo4O13—(0.889<xMoO 3<1); (2) in the MoO3_Cd system at 500 °C, Cd, MoO2, CdMoO4—(0<xMoO 3<0.6667) and MoO3, MoO2, CdMoO4—(0.6667<xMoO 3<1); and (3) in the MoO3-Sb system at 600 °C, Sb, MoO2, Sb4Mo10O31—(0<xMoO 3<0.734) and MoO3+MoO2+Sb4Mo10O31 (0.734<xMoO 3<1). The results lead to construction of ternary phase diagrams: Te-MoO3-TeMo4O13, Cd-MoO3-CdMoO4, and Sb-MoO3-Sb4Mo10O31. 相似文献
4.
Renjith Devasia CP Reghunadhan Nair P Sivadasan KN Ninan 《Polymer International》2005,54(8):1110-1118
Polyacrylonitrile terpolymers of various compositions consisting of acrylonitrile (AN), itaconic acid (IA) and methyl acrylate (MA) were synthesized by solution polymerization in dimethylsulfoxide. Increase in concentration of either IA or MA retarded the overall polymerization rate and the polymer molecular weight. The system consisting of AN + MA and varying IA concentration was more prone to retardation in comparison with the system composed of AN + IA with variable MA concentration. The retardation factors were quantified. Minor quantities of MA boost the reactivity of IA in the terpolymer system. The terpolymer was richer in MA vis‐à‐vis the feed. The thermal characteristics of the terpolymer were examined as a function of its composition. In contrast to the copolymer of AN and IA requiring 1–1.5 mol% IA, the terpolymer required an IA content of approximately 2.5 mol% for optimum thermal stability. The polymer with 90 mol% AN, 2.5 mol% IA and 7.5 mol% MA exhibited reasonably good char‐forming characteristics and thermal stability. The overall crystallinity and crystallite size of the polymers were found to decrease on incorporation of the comonomers. The ‘aromatization index’ of the copolymer increased with the temperature of pyrolysis through re‐organization of the tetrahydropyridine ladder structure. Copyright © 2005 Society of Chemical Industry 相似文献
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6.
KN Michailova 《Canadian Metallurgical Quarterly》1996,178(1):91-99
OBJECTIVE: To develop a method to predict long-term outcome after head injury and determine if outcome can be accurately predicted 24 hours after injury. DESIGN: A retrospective review was performed on a study cohort of 672 head-injured patients admitted in coma (Glascow Coma Scale score < or = 8) who remained comatose for at least 6 hours, survived more than 24 hours, and had 6-month outcome data available. Stepwise logistic regression analysis was used to determine which clinical variables predicted 6-month outcome. Statistically significant clinical predictors were combined into a single examination variable (MPX score), which reflected a rank-ordering of examinations from worst to best, which was then further weighted by patient age. The relation between 6-month outcome and MPX score at admission and 24 hours was plotted and analyzed. MEASUREMENT AND MAIN RESULTS: Age, best motor score, and pupillary reactivity at admission and 24 hours were significant predictors of outcome; extraocular motility was predictive at 24 hours only. Age was the most important independent predictor, followed by best motor score, pupillary reactivity, and extraocular motility. Combining these predictors into MPX score resulted in a set of graphs that reliably predicted long-term outcome. The 24-hour MPX data were better predictors of 6-month outcome and were more specific in predicting negative outcomes than admission data. CONCLUSIONS: The method is simple to use, relying on bedside neurologic examination and a single graph, but appears to predict long-term outcome accurately as early as 24 hours after head injury. If validated on other large series of patients, this method could provide an objective and practical basis for terminating care in patients unlikely to survive a head injury. 相似文献
7.
Surface expression of the T cell antigen receptor (TCR) in mature T cells requires the association of a variable heterodimer (alpha.beta or gamma.delta) with six invariant CD3 polypeptides (gamma, delta, epsilon-epsilon, zeta-zeta, or zeta-eta). We described here that deletion of the cytoplasmic tail polypeptide sequence (Lys-Lys-Lys-Asn-Ser) of TCR beta-chain (beta CT) results in expression of the truncated beta-chain on the surface of a mature T cell hybridoma line, in the absence of TCR-alpha, as a glycophosphatidylinositol (GPI)-anchored monomeric polypeptide. The GPI-anchored TCR-beta CT is not associated with CD3-epsilon and is incapable of conventional signal transduction. Association with TCR-alpha prevents beta CT from GPI-linkage formation. The alpha beta CT heterodimer binds the CD3 polypeptides, and the resultant TCR alpha beta CT/CD3 complex is capable of signal transduction. Our data show that a signal sequence for GPI-linkage formation is present in TCR-beta, and this alternative membrane anchoring mechanism can be utilized by beta-chain polypeptide lacking the CT sequence. We conclude therefore that in the absence of TCR-alpha expression, the beta-chain CT sequence plays an essential function in hindering GPI-linkage formation, thereby preventing escape of incompletely assembled TCR beta-chain to the cell surface of mature T cells. 相似文献
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9.
GL Anderson KN Caldwell LR Beuchat PL Williams 《Canadian Metallurgical Quarterly》2003,66(9):1543-1549
Free-living nematodes may harbor, protect, and disperse bacteria, including those ingested and passed in viable form in feces. These nematodes are potential vectors for human pathogens and may play a role in foodborne diseases associated with fruits and vegetables eaten raw. In this study, we evaluated the associations between a free-living soil nematode, Caenorhabditis elegans, and Escherichia coli, an avirulent strain of Salmonella Typhimurium, Listeria welshimeri, and Bacillus cereus. On an agar medium, young adult worms quickly moved toward colonies of all four bacteria; over 90% of 3-day-old adult worms entered colonies within 16 min after inoculation. After 48 h, worms moved in and out of colonies of L. welshimeri and B. cereus but remained associated with E. coli and Salmonella Typhimurium colonies for at least 96 h. Young adult worms fed on cells of the four bacteria suspended in K medium. Worms survived and reproduced with the use of nutrients derived from all test bacteria, as determined for eggs laid by second-generation worms after culturing for 96 h. Development was slightly slower for worms fed gram-positive bacteria than for worms fed gram-negative bacteria. Worms that fed for 24 h on bacterial lawns formed on tryptic soy agar dispersed bacteria over a 3-h period when they were transferred to a bacteria-free agar surface. The results of this study suggest that C. elegans and perhaps other free-living nematodes are potential vectors for both gram-positive and gram-negative bacteria, including foodborne pathogens in soil. 相似文献
10.