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421.
422.
In this study, an orthogonal intermittent machining test for aluminum alloy 5052 was conducted under dry conditions. By using cutting forces that were measured during the test, the frictional properties of a tool rake face were evaluated during intermittent machining for two types of diamond-like carbon (DLC)-coated tools and an uncoated carbide tool. DLC films used in the test were composed of tetrahedral amorphous carbon (ta-C) deposited by a filtered arc deposition process and hydrogenated amorphous carbon (a-C:H) deposited by a plasma-enhanced chemical vapor deposition process. The test results showed that the initial friction coefficients were approximately 0.8 for all tools. However, with increasing machining time, the friction coefficient of only the ta-C-coated tool decreased remarkably to a lower value of 0.3, whereas those of the a-C:H-coated tool and the uncoated carbide tool remained high. An electron probe micro analyzer (EPMA) analysis revealed an area where no aluminum adhered on the ta-C-coated tool rake face after intermittent machining. This area provided low frictional properties during intermittent machining. An X-ray photoelectron spectroscopy (XPS) analysis showed that the carbon bonding of the DLC film surface in this area had changed from the state before machining.  相似文献   
423.
Arabidopsis thaliana can be a useful model plant in the field of plant molecular biology because it is a sole dicotyledonous plant whose genome sequence has been completely determined at the present time. To develop functional genomics of A. thaliana, a large number of transgenic plants must be produced. However, transformation of the plants requires wide space and long time. For these reasons, a highly efficient method has been desired to be developed. In order to save space, the transformation system was improved, based on a new technology for plant propagation using ceramic tubes. The new method using ceramic tubes facilitated to prepare plants with a uniform growth level. In addition, the colander procedure after infiltration, which is one of tedious procedures, could be omitted. The new system without soil usage could cut down the cleaning up after experiment.  相似文献   
424.
InPsychosemantics Jerry Fodor offered a list of sufficient conditions for a symbol X to mean something X. The conditions are designed to reduce meaning to purely non-intentional natural relations. They are also designed to solve what Fodor has dubbed the disjunction problem. More recently, inA Theory of Content and Other Essays, Fodor has modified his list of sufficient conditions for naturalized meaning in light of objections to his earlier list. We look at his new set of conditions and give his motivation for them-tracing them to problems in the literature. Then we argue that Fodor's conditions still do not work. They are open to objections of two different varieties: they are too strong and too weak. We develop these objections and indicate why Fodor's new, improved list of conditions still do not work to naturalize meaning.We wish to thank Ray Elugardo, Pat Manfredi, and Donna Summerfield for comments on a draft of this paper, as well as other members of the CMU Mind Group (David Drebushenko, Gary Fuller, and Naomi Reshotko) for helpful discussion and support. A version of this paper was presented at the Southern Society for Philosophy and Psychology in Atlanta, March, 1991, and at the Canadian Society for History and Philosophy of Science in Kingston, Ontario, in May, 1991.  相似文献   
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