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排序方式: 共有630条查询结果,搜索用时 15 毫秒
1.
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
2.
S Kasiviswanathan P S Asoka Kumar B K Mathur K L Chopra 《Bulletin of Materials Science》1996,19(2):411-416
Surface structure of thin silver films (200 Å) on two technologically important films, indium tin oxide (ITO) and aluminium oxide, has been studied using scanning tunneling microscope. ITO films were prepared by reactive electron beam evaporation. Aluminium oxide films were prepared by oxidizing 2000 Å thick aluminium films evaporated on to H2 terminated single crystal silicon substrates. The surface structure of silver on ITO and aluminium oxide appeared to be same and was characteristic of Stranski-Krastanov type. The observed asymmetry in the island shape was attributed to the anisotropic nature of the strain fields surrounding the nucleation centres. 相似文献
3.
4.
A.Varada Rajulu G. Babu Rao B. Ravi Prasad Rao A. Madhu Sudana Reddy Jiasong He Jun Zhang 《应用聚合物科学杂志》2002,84(12):2216-2221
Studies on some properties such as the density, the degradation temperatures, the morphology and the spectral features of the ligno‐cellulose fiber Hildegardia were carried out in both untreated and alkali treated form. The fibers are found to have good morphology and moderate initial and final degradation temperatures. On alkali treatment, the lignin was found to be eliminated. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2216–2221, 2002 相似文献
5.
A classical ionic inorganic complex Na2[Cu(mnt)2] (mnt2− = maleonitriledithiolate = 1,2-dicyanoethylenedithiolate), that acts as a template in assembling neutral [Cu(salen)] (salen = bis(salicylidene)ethylenediamine) complexes forming a framework type arrangement, is accommodated in the channel formed in the crystal structure of a new type of host–guest compound [Cu(salen)]4 · Na2[Cu(mnt)2] (1). The non-covalent supramolecular interactions among [Cu(salen)] complexes and between [Cu(salen)] and [Cu(mnt)2]2− complexes in the crystal lattice of 1 result in weak antiferromagnetic coupling. 相似文献
6.
A basic goal in property testing is to identify a minimal set of features that make a property testable. For the case when the property to be tested is membership in a binary linear error-correcting code, Alon et al. (Trans Inf Theory, 51(11):4032–4039, 2005) had conjectured that the presence of a single low-weight codeword in the dual, and “2-transitivity” of the code (i.e., the code being invariant under a 2-transitive group of permutations on the coordinates of the code) suffice to get local testability. We refute this conjecture by giving a family of error-correcting codes where the coordinates of the codewords form a large field of characteristic two, and the code is invariant under affine transformations of the domain. This class of properties was introduced by Kaufman & Sudan (STOC, 2008) as a setting where many results in algebraic property testing generalize. Our result shows a complementary virtue: This family also can be useful in producing counterexamples to natural conjectures. 相似文献
7.
Tushar Chopra Mitchell H. Rosner 《Hemodialysis international. International Symposium on Home Hemodialysis》2017,21(1):11-18
The past year has seen interesting publications in the fields of chronic kidney disease and end stage renal disease. This review highlights some of these important papers and places their findings in the context of clinical care. 相似文献
8.
S. K. Mishra L. C. Pathak V. Rao D. Bhattacharya K. L. Chopra 《Journal of Superconductivity》1996,9(2):211-216
Critical current densities of the superconducting Y-Ba-Cu-O (YBCO) films have been observed to decrease with the increase of power of microwave radiation. Presence of Josephson type of junctions in the microbridges has been established from the microwave irradiation and magnetic field studies. BCS energy gap parameter (2/kT
c
) has been calculated from thedI/dV characteristics and found to be 3.7 at 13 K. 相似文献
9.
Conjugated linoleic acid, a fatty acid found in milk fat and ruminant meat is one of the functional food components. Modifying fatty acid composition so as to increase CLA and other beneficial PUFA/MUFA level and reducing SFA levels might be a key to enhance the neutraceutical and therapeutic value of ruminant-derived food products. In the present experiment, the effect of supplementation of polyphenol rich Terminalia chebula plant extract at different concentrations (1.06 g/kg and 3.18 g/kg of body weight in T1 and T2 groups, respectively) was investigated on fatty acid composition of rumen fluid, plasma, intramuscular fat and Δ9-desaturase activity in longissimus dorsi muscle of crossbred kids. Total MUFA and PUFA content in muscle were enhanced by 25 and 35%, respectively, whereas SFA was reduced by 20% thereby improving the desaturation index. Δ9-desaturase activity also increased by 47% resulting in an enhancement of total CLA content (58.73%) in muscle. 相似文献
10.
Determination of antioxidant potential of Acacia nilotica leaf extract in oxidative stress response system of Saccharomyces cerevisiae 下载免费PDF全文