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41.
Computer network as a force drags its customers to share more and more resources while on the other hand managing such network recourses is a challenging job for an IT professional and perhaps becoming difficult humanly. In this paper, we have proposed an agent based system for activity monitoring on network (ABSAMN) for the monitoring of resources over a network, suitable for network of networks; commonly known as CAN (campus area network). Multi-agent system is a system composed of several agents, collectively capable of achieving goals that are difficult to achieve by an individual agent or monolithic system. We propose the use of multi-agent system to ensure proper system operation by watching for inconsistencies in user activities, node level activity, internet monitoring, and system configuration. The system is fully autonomous and once initialized with the given rules and domain knowledge ABSAMN manages resources on its own with the help of mobile agents. We have evaluated this architecture on the university campus having seven labs equipped with 20–300 number of PCs in various labs. Results were very promising and support the implementation of the solution.  相似文献   
42.
The phenomenon of grain refinement was studied in a steel containing 0.15% C, 0.32% Si, 1.4% Mn, and 0.43% V. Initial austenite grain size was found to be 50 μm, determined by quenching the specimen in an iced brine solution from 1150 °C. Transformational grain refinement (TGR) was applied to give a reasonable refinement in the grain size. A rolling reduction of about 67% was given to specimens at 900 °C, which was followed by air cooling. Cold rolling and recrystallization of these specimens gave refinement of grains down to 1 μm size was obtained. The electron backscattered diffraction (EBSD) technique was used to determine low- and high-angle grain boundaries that are effectively used to determine the substructure contribution at various stages of recrystallization.  相似文献   
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In the present studies, the immuno-enhancing activity of Rheum emodi ethyl acetate rhizome extract has been carried out by conducting studies on the cell lines. The studies include effects on signal transduction parameters that could pave the way for understanding some of the treatment principles of the plant extracts. The data indicate that R. emodi may have an immuno-enhancing effect through the release of various cytokines. There is a dose dependent increase in the release of NO (nitric oxide) and cytokine TNF-α, IL-12 and a decrease in IL-10 by RAW 264.7 in macrophage cell lines in the presence of extract alone. However the cytokine level is concomitantly increased in the presence of stimulant as well as extract. The up-regulation of TNF-α, and IL-12 up to the level of 200 ng/ml and 530 ng/ml respectively switches the cell towards Th-1 immune response. TNF-α, IL-12 induces generation and proliferation of Th-1 cells which in turn produces NK and cytotoxic T-cells. On the other hand, the decreased levels of IL-10 switches off the Th-2 immune system and directs the cell towards Th-1 immune response only. Thus, indicating that R. emodi extract may have anti-tumour effects by regulating Th-1 and Th-2 immune response in vivo.  相似文献   
45.
Yttrium and cerium co-doped ZnO nanoparticles were synthesized by combustion route and characterized using X-ray diffraction(XRD),scanning electron microscopy(SEM),Brunauer-Emmett-Teller(BET),energy dispersive spectroscopy(EDS),X-ray photoelectron spectroscopy(XPS),UV-visible diffuse reflectance spectroscopy(UV-vis DRS),photoluminescence(PL)and electrochemical impedance spectroscopy(EIS)techniques.The introduction of yttrium ions has efficiently increased the relative percentage of Ce3+ions in ZnO.Yttrium and cerium co-doped ZnO shows efficient photo activity for hydrogen evolution(10.61 mmol/((g·h))higher than previously reported optimal value for rare earth codoped ZnO photocatalysts.This remarkably increased hydrogen evolution can be ascribed to the synergy between electronic anchoring effect of Y3+/Y2+and Ce4+/Ce3+redox couples.This report presents new idea for the synthesis of efficient photocatalyst using economical route and ion anchoring effect.The hydrogen evolution was also tested using Na2S and Na2SO3as electron donors under visible light illumination.The synthesized photocatalysts also exhibit high stability.  相似文献   
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The pollen morphology, with special reference to exine sculpture, of some species of the gymnosperms was assessed for the first time from the subalpine and alpine zones of western Himalayas northern Pakistan. The pollen of all these species is airborne and allergenic, so pollen morphology helps for identification of this allergenic pollen at specific level. Different morpho-palynological characteristics were analyzed including size range of pollen, polar and equatorial diameter ratio, exine ornamentation, sculpturing, exine thickness, pollen type, and shape. For accurate and quick identification of species, taxonomic key was made based on different morpho-palynological characteristics. The quantitative data were processed using SPSS software. Gymnospermal pollen includes inaperturate, rarely 1-colpate observed in (Cupressaceae), hexazonocolpate in (Ephedraceae), vesiculate, bissacate in (Pinaceae), and inaperturate in (Taxaceae). Different pollen shapes observed were prolate (4 spp), sub-spheroidal (7 spp), and oblate (1 spp). Variation was observed in exine sculpturing granular (4 spp), reticulate (1 spp), areolate-punctate (3 spp), and psilate (2 spp). This is based on the analysis of 10 plants belonging to four families of gymnosperms. Distinct pollen shape has emerged as the most diagnostic feature to separate some genera such as spheroidal in (Cupressaceae, Taxaceae), prolate and radiosymmetrical in (Ephedraceae), and bilateral in (Pinaceae). Exine thickness and sculpturing proved to be helpful at generic and specific levels. The results reinforced the significance of gymnospermal pollen morphological features which were used as aid for valuable taxonomic tool in plant systematics.  相似文献   
48.
Abstract: Rice starch is one of the major cereal starches with novel functional properties. Significant progress has been made in recent years on the characterization of rice starches separated from different rice cultivars. Studies have revealed that the molecular structure and functional properties are affected by rice germplasm, isolation procedure, climate, agronomic conditions, and grain development. Morphological studies (microscopy and particle size analysis) have reflected significant differences among rice starch granule shapes (polyhedral, irregular) and in granule size (2 to 7 μm). Nonwaxy and long‐grain rice starches show greater variation in granular size than the waxy starches. Rice starch granules are smaller than other cereal starches with amylose contents varying from virtually amylose‐free in waxy to about 35% in nonwaxy and long‐grain rice starches. Amylose content appears to be the major factor controlling almost all physicochemical properties of rice starch due to its influence on pasting, gelatinization, retrogradation, syneresis, and other functional properties. Waxy rice starches have high swelling and solubility parameters, and larger relative crystallinity values than nonwaxy and long‐grain starches. However, nonwaxy rice starches have a higher gelatinization temperature than the waxy and long‐grain starches. The bland taste, nonallergenicity, and smooth, creamy, and spreadable characteristics of rice starch make it unique and valuable in food and pharmaceutical applications. This review provides recent information on the variation in the molecular structure and functional properties of different rice starches.  相似文献   
49.
In this study, plants belonging to family Solanaceae growing in Western Himalaya region have been observed palynologically under Light Microscope and Scanning electron microscope. Present investigation comprises of 10 genera and 23 species, namely, Atropa acuminata, Capsicum decoraticus, Capsicum frutescens, Cestrum aurantiacum, Cestrum diurnum, Cestrum nocturnum, Datura alba, Datura innoxia, Datura stramonium, Hyoscymus niger, Lycopersicon esculentum, Nicotiana rustica, Nicotiana tabacum, Petunia alba, Petunia hybrida, Solanum erianthum, Solanum melongena, Solanum miniatum, Solanum pseudocapsicum, Solanum surratense, Solanum tuberosum, Withania coagulans, Withania somnifera. Solanaceae is a eurypalynous family. Grains are usually Tricolporate and Tetracolporate, radially symmetrical, isopolar, prolate‐spheroidal to oblate‐spheroidal to oblate‐spheroidal to subprolate to per prolate or suboblate to oblate, size range: 8.55–72 μm, amb circular, semi‐angular or subangular, aperture drop‐type, labrum common‐type, exine usually 2 μm thick, nexine 1–1.5 μm thick. Tectum usually psilate, sexine reticulate, granulate or striato‐reticulate, with obscure pattern, sexine 1–2 μm thick, nexine 1–1.5 μm thick, and intine 0.5–1 μm thick. Most striking variation has been found in the shape class, aperture‐type, and tectal surface. Based on these characters, taxonomic keys have been made for correct identification of members in Solanaceae. However, the grains of this family are usually tricolporate and have direct relationship with certain members of the family Scrophulariaceae. Palyno‐morphological characters of family Solanaceae have been studied for the first time in Western Himalayan region of Pakistan. These palyno‐morphological characters are significant for identification of the members of family Solanaceae.  相似文献   
50.
Al 6061100–xx wt % B4C (x = 0, 5, 10, 20, 30 and 40) composites, prepared by mechanical alloying and compacted at room temperature, have been used for the present investigation. The effects of B4C content and milling time on the powder morphology, powder particle size, and other powder characteristics such as the apparent density, tap density, flow rate, cohesiveness, and hausner ratio are systematically investigated. The steady state of milling process is determined by observing the correlation between apparent densities and milling time explained by the morphological evolution of the powder particles during the milling process. The Hausner ratio (HR), estimated to evaluate friction between the particles, decreases with an increase in milling duration and B4C content due to the changes in morphology and hardness of the powders. The compressibility behavior of post-compacts as a function of compaction pressure and the B4C content was analyzed by using several linear and non-linear powder compaction equations. The linear Panelli and Ambrozio Filho, and non-linear Van Der Zwan and Siskens equations give the highest regression coefficients. The results are explained in terms of the plastic deformation capacity and plastic deformation coefficient of the powders, which are influenced by the hardness and the morphology of the powder. After compaction, the supersolidus liquid phase sintering was performed at various temperatures (585, 610 and 630°C) under high purity nitrogen atmosphere. The results revealed that the sinterability was degraded by increasing the reinforcement content, particularly above 10 wt % B4C. Neutron radiography measurements conducted on the rolled composite sheet have revealed the uniform distribution of B4C particles in the composite.  相似文献   
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