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71.
T. Sampath Kumar S. Balasivanandha Prabu Geetha Manivasagam K. A. Padmanabhan 《矿物冶金与材料学报》2014,21(8):796-805
Monolayer and bilayer coatings of TiAlN, AlCrN, and AlCrN/TiAlN were deposited onto tungsten carbide inserts using the plasma enhanced physical vapor deposition process. The microstructures of the coatings were characterized using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The SEM micrographs revealed that the AlCrN and AlCrN/TiAlN coatings were uniform and highly dense and contained only a limited number of microvoids. The TiAlN coating was non-uniform and highly porous and contained more micro droplets. The hardness and scratch resistance of the specimens were measured using a nanoindentation tester and scratch tester, respectively. Different phases formed in the coatings were analyzed by X-ray diffraction (XRD). The AlCrN/TiAlN coating exhibited a higher hardness (32.75 GPa), a higher Young’s modulus (561.97 GPa), and superior scratch resistance (LCN = 46 N) compared to conventional coatings such as TiAlN, AlCrN, and TiN. 相似文献
72.
By electron diffraction pattern the presence of metallic elements, particularly chromium-nickel, chromium phosphide, copper, aluminum-copper and zinc has been shown in the pineal organ of a freshwater teleost, M. vittatus. It is likely that their occurrence within the pineal is due to binding with the neurosecretory material fractions/ligands. 相似文献
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Summary Acetylcholinesterase (AChE) activity was studied in the glycogen bodies of the spinal cords of 2 birds namelyStreptopelia senegalensis andPasser domesticus. A possible functional significance of AChE in the light of relative enzymatic localization especially in Hoffmann-Kolliker
nuclei (motor cell groups), substantia gelatinosa and other regions of gray matter of 2 avian glycogen bodies has been discussed. 相似文献
75.
Human immunodeficiency virus type 1 (HIV-1) is the aetiologic agent of AIDS (acquired immune deficiency syndrome) in most countries and probably originated in Central Africa like the AIDS epidemic itself. Evidence for a second major group of human immunodeficiency-associated retroviruses came from a report that West African human populations like wild-caught African green monkeys had serum antibodies that reacted more strongly with a simian immunodeficiency virus (STLV-3Mac) (ref.6) than with HIV-1. Novel T-lymphotropic retroviruses were reported to have been isolated from healthy Senegalese West Africans (HTLV-4) (ref. 4) and from African green monkeys (STLV-3AGM) (ref. 7), and a different retrovirus (HIV-2) was identified in other West African AIDS patients. Genomic analysis of HIV-2 clearly distinguished it from STLV-3 (ref. 9), but restriction enzyme site-mapping of three different HTLV-4 isolates and six different STLV-3AGM isolates showed them to be essentially indistinguishable. In this report we clone, restriction map, and partially sequence three isolates of HTLV-4 (PK82, PK289, PK190) (ref. 4). We find that these viruses differ in nucleotide sequence from each other and from three isolates of STLV-3AGM (K78, K6W, K1) (ref. 7) by 1% or less. We also report the isolation of a T-lymphotropic retrovirus from the peripheral blood of a healthy Senegalese woman which hybridizes preferentially to HIV-2 specific DNA probes. We conclude that HTLV-4 (ref. 4) and STLV-3AGM (ref. 7) are not independent virus isolates and that HIV-2 is present in Senegal as it is in other West African countries. 相似文献
76.
S. Kumar 《Cellular and molecular life sciences : CMLS》1970,26(2):217-217
Zusammenfassung Diskussion über die Frage der Ätiologic der Xanthinurie. 相似文献
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78.
In the recent years, a plethora of computerized expert systems has been developed for various sectors of agriculture in India. The availability of low-cost computers, agricultural knowledge and information technology professionals are the principal reasons for the development of so many agricultural expert systems. Among all agricultural expert systems, the expert systems for crop protection need special mention. These expert systems are meant to be used by farmers and other persons without much experience of using computers. Hence, special care must be taken while developing them. The current paper develops a taxonomy for the expert systems for crop protection and briefly discusses four such expert systems for crop protection being used in India. 相似文献
79.
80.
In the recent years, a plethora of computerized expert systems has been developed for various sectors of agriculture in India. The availability of low cost computers, agricultural knowledge and information technology professionals are the principal reasons for the development of so many agricultural expert systems. Among all agricultural expert systems, the expert systems for crop protection need special mention. These expert systems are meant to be used by farmers and other persons without much experience of using computers. Hence, special care must be taken while developing them. The current paper develops a taxonomy for the expert systems for crop protection and briefly discusses four such expert systems for crop protection being used in India. 相似文献