607 research outputs found

    Analysis of the influence of natural wear and tear in gates and runners on the filling of a balanced multi-cavity injection mold

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    Design of injection molds is outmost important in the manufacture of parts. Its components runners and gates significantly influence the mold filling. Using a simulation package for injection molding a balanced multi-cavity mold was designed. Wear in the gates of runner was simulated by varying the cross-sectional area of the components. Influence of wear of tear in gates of runners on mold filling was measured in terms of flow rate of time of fill. Detailed analysis is done on four different models using four different materials Polycarbonate, Polypropylene, Nylon6 and Polybutylene terephthalate. Graphical display of result is presented and analyzed in terms of deviation in time of fill and flow rate from their original values. Remedies suggested for reducing the affects of wear and tear and replacement of the equipment

    Durability and Microstructure Characteristics of Concrete with Supplementary Cementitious Materials

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    Considering the environmental impact of cement manufacturing industries, this paper concerns the potential of using supplementary cementitious materials (SCMs), like fly ash and ground granulated blast furnace slag, as being essential to replacing the existing Ordinary Portland Cement (OPC). The objective of this paper is to study the microstructural characteristics of concrete with SCMs and improve the durability of the product to increase the lifespan of concrete structures. Replacement SCMs in OPC are 0, 40, 50, and 60 by percentage of cement weight, and we have taken a water-binder ratio of 0.40 for M40 grade and 0.28 for M60 grade concrete. The physical properties and chemical composition of OPC, Ground Granulated Blast-furnace Slag (GGBS), and fly ash were identified, and three different experiments were conducted to determine the resistance to penetration of chloride ions and corrosion processes. The rapid chloride permeability test, accelerated corrosion, and sorptivity tests were employed to measure concrete's resistance to the effects of aggressive environments and examine the durability properties. The most performed grade samples were analyzed as individual microspheres with Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDXS), and X-ray diffraction. Significant improvements in various concrete properties were achieved through the partial replacement of fly ash and GGBS with cement. Doi: 10.28991/CEJ-2022-08-04-05 Full Text: PD

    World review of the natural enemies and diseases of Spodoptera litura(F.)(Lepidoptera: Noctuidae)

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    Published information was used to compile a summary of natural enemies(parasitoids, predatorsand diseases) reported attacking Spodoptera litirra (F) under field conditions. Species (71) of insect parasitoids in seven families of Hymenoptera and two families of Diptera were listed as parasitoids of difTerent stages of S. litura. Predatory insects (36) belonging to 14 families and 12 species of spiders from six families have been reported to feed on this species. Four prolozoan, four fungal, seven bacterial, four each of viral and nematode species were also reported to be the pathogens of this species. Published information suggested that periodic releases of large number of egg parasites could help in suppressing populalions of this pest. There is a considerable scope for increased attention to the role of natural enemies as component of integrated pest management programmes of S. litura

    Threshold Temperatures and Thermal Requirements for the Development of Spodoptera litura (Lepidoptera: Noctuidae)

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    Developmental thresholds and thermal requirements for different stages of Spodoptera litura (F.) fed on groundnut leaves were determined under constant laboratory conditions and in the field. An average of 64 degree-days (DD) above a threshold of 8°C was required from oviposition to egg hatch; the larval period required 303 DD and pupal stage 155 DD above a 10°C threshold; females needed 29 DD above a 10.8°C threshold from emergence to oviposition. Fifth and sixth instars accounted for about 50%of the total larval requirement under laboratory and field conditions. The response of various stages of S. litura to temperatures under constant laboratory conditions was similar to that under field conditions. The upper developmental threshold temperature of all stages was 37°C; 40°C was lethal

    Changes in liver lipids after administration of 2‐decanoylamino‐3‐morpholinopropiophenone and chlorpromazine

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    The enzyme which forms glucocerebroside, ceramide: UDP‐glucose glucosyltransferase, is inactivated in vitro by a cationic analog of cerebroside, 2‐decanoylamino‐3‐morpholinopropiophenone. A study of the inhibitor using intraperitoneal injection into young mice showed that the level of the enzyme activity in liver was appreciably lowered between 3 and 6 hr after injection. The activity increased subsequently, overshooting the normal level within 24 hr by about 20%, then returning to normal within the next 24 hr. Additional effects observed in liver were an increase in lipid content (primarily in the triglyceride fraction and ceramides) and a decrease in the glucocerebroside level. Body temperature dropped rapidly. Markedly similar effects were produced by injecting chlorpromazine, which was tried in order to reduce the hyperirritability and inhibitory effects on monoamine oxidase previously demonstrated by the glucosyltransferase inhibitor. Chlorpromazine did indeed block the hyperirritability and resulted in enhancement of the keto amine’s effects on the enzyme and lipids. It is possible that the two drugs in combination would be helpful in ameliorating the symptoms due to the cerebroside accumulation that occurs in Gaucher disease. Diazepam also produced a reduced level of glucosyltransferase. A color reaction for chlorpromazine, possibly suitable for quantitative determination in tissues, was accidentally discovered.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142035/1/lipd0538.pd

    The Power of Predictions and Probabilities

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    Monsoon rainfall in India varies every year, and distribution is uncertain. This poses a production risk for farmers in the semi-arid India. Farmers tend to ignore rainfall forecasts issued by the Indian Meteorological Department (IMD) while making crop decisions since they are made for the whole country, and could be unreliable regionally. Recent advances in forecasting techniques improve the usefulness of forecasting seasonal rainfall. Farmers in USA, Australia, Argentina and Brazil benefit from forecast-based cropping decision options to enhance agricultural productivity.............

    Neem: the Bitter Truth

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    The insecticidal properties of plants have been known through the ages. In recent years botanical insecticides have played a critical role in the management of several insect pests. However, they have not been fully exploited on a commercial scale. Neem (Azadirachta indica) has been the focus of studies for over 20 years, and neem products are used as pesticides and allied chemicals against >250 insect species all over the world
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