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Environmental Science and Pollution Research - The paper provides an overview of biocosmetics, which has tremendous potential for growth and is attracting huge business opportunities. It emphasizes...  相似文献   
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With a solid-phase radioimmunoassay it has been possible to detect species-specific collagen and albumin in fossils as old as 1.9 million years. This technique may provide new data on the genetic relations of fossil species to each other and to living forms.  相似文献   
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The intensive temperatures in high speed machining not only limit the tool life but also impair the machined surface by inducing tensile residual stresses, microcracks and thermal damage. This problem can be handled largely by reducing the cutting temperature. When the conventional coolant is applied to the cutting zone, it fails to remove the extent of the heat effectively. Hence, a cryogenic coolant is highly recommended for this purpose. In this paper, an attempt has been made to use cryogenic carbon dioxide (CO2) as the cutting fluid. Experimental investigations are carried out by turning AISI 1045 steel in which the efficiency of cryogenic CO2 is compared to that of dry and wet machining with respect to cutting temperature, cutting forces, chip disposal and surface roughness. The experimental results show that the application of cryogenic CO2 as the cutting fluid is an efficient coolant for the turning operation as it reduced the cutting temperature by 5%–22% when compared with conventional machining.It is also observed that the surface finish is improved to an appreciable amount in the finished work piece on the application of cryogenic CO2. The surface finish is improved by 5%–25% in the cryogenic condition compared with wet machining.  相似文献   
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This paper is concerned with the control of aircraft noise. Some brief remarks are made on the relationship of aircraft noise problems to the theoretical approaches to externalities. We note in particular that an effluent charge is the most practical way to deal with the problem. A linear programming technique is used to find the bundle of noise-reducing options that minimizes the cost of achieving noise reduction goals, given an upper limit on service reduction. A rate-of-return criterion is imposed on the l.p. solution. Shadow prices are used to generate charges on the airlines. This provides a stimulus for abatement without dictating actual methods. Implicit in the cost parameters are prices of aircraft fuel. We assess the attractiveness of the abatement options with increasing fuel prices. The mechanics of the actual implementation of the charge in the airline industry is examined. We conclude that the institution of a plan such as the one proposed here will provide control of aircraft noise in a socially efficient manner.  相似文献   
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