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111.
In this study, the effects of the phosphonic acid based sequestering agent EDTMPA used in the textile dye baths on colour and organic matter removal by ozone oxidation was experimentally investigated. Procion Navy HEXL dyestuff that has been commonly used for the reactive dyeing of cellulose fibers was selected as the model component. The organic matter oxidation by ozone was determined to obey the pseudo-first order kinetics as they are treated singly or in combination. COD removal rates obtained from pseudo-first order reaction kinetics showed that oxidation of Navy HEXL alone (0.0947 L/min) was faster than that of EDTMPA (0.0171 L/min) and EDTMPA with dye (0.0155 L/min) at pH 3.0. It was also found that reaction rates of single EDTMPA removal and EDTMPA and dye mixture removal increased as the reaction pH was increased from 3.0 to 10.5.  相似文献   
112.
As the level of microprocessor complexity increases to several hundred thousand transistors for a single-chip machine, it is becoming very difficult to test commercially available designs to the level of fault coverage desired by some customers. In order to achieve near 100-percent coverage of single stuck-at faults, future microprocessors must be designed with special testing features (designed for testability). The authors describe the testing problem for microprocessors, including the various methods of generating test sets and their application by the user. A survey of the testability features of some of today's commercially available microprocessors is presented. Suggestions for testability features for future-generation microprocessors are also discussed  相似文献   
113.
The StoryGrid project undertook studying the role new interface technologies might play in education, particularly at the high school level. Unfortunately, technology often seizes center stage in high school classrooms; i.e., it becomes the topic of instruction. We believe that learning about technology would be most successful when technology is not the topic, but simply a tool used during instruction. StoryGrid, therefore, was designed to support and to enhance existing narrative activity in classrooms by adhering to the following goals: trigger reflection and interpretation, accommodate individual expression and encourage student discourse.  相似文献   
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The paper describes a few modifications of the classification tree construction algorithm that have proved to be useful for solving tasks of noise spectra processing with reference to NPP diagnostics. The article was translated by the authors.  相似文献   
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It is demonstrated for X-ray diffraction from a bent crystal in the backscattering mode that the Bragg angle in the crystal can differ from the value in vacuum by ∼10−2. This difference exceeds the angular width of the region of total reflection for the CuKα radiation backscattered from the (220) plane of a silicon single crystal. The Bragg law modified with allowance for the refraction and crystal bending is presented.  相似文献   
119.
Many zeranol immunoassay test kits cross-react with toxins formed by naturally occurring Fusarium spp. fungi, leading to false-positive screening results. This paper describes the evaluation and application of recently published, dry reagent time-resolved fluoroimmunoassays (TR-FIA) for zeranol and the toxin alpha-zearalenol. A ring test of bovine urine fortified with zeranol and/or alpha-zearalenol in four European Union National Reference Laboratories demonstrated that the TR-FIA tests were accurate and robust. The alpha-zearalenol TR-FIA satisfactorily quantified alpha-zearalenol in urine fortified at 10-30 ng ml(-1). The specificity-enhanced zeranol TR-FIA accurately quantified zeranol in the range 2-5 ng ml(-1) and gave no false-positive results in blank urine, even in the presence of 30 ng ml(-1) alpha-zearalenol. Zeranol TR-FIA specificity was demonstrated further by analysing incurred zeranol-free urine samples containing natural Fusarium spp. toxins. The TR-FIA yielded no false-positive results in the presence of up to 22 ng ml(-1) toxins. The performance of four commercially available zeranol immunoassay test kits was more variable. Three kits produced many false-positive results. One kit produced only one potential false-positive using a protocol that was longer than that of the TR-FIA. These TR-FIAs will be valuable tools to develop inspection criteria to distinguish illegal zeranol abuse from contamination arising from in vivo metabolism of Fusarium spp. toxins.  相似文献   
120.
Three kinds of statistical distributions of DC microdischarges in homogeneous electric field are discussed. So far the exponential and streamer distributions have been considered as regular statistics describing microdischarge electron avalanches with low (n~<10/sup 5/) and high (n~>10/sup 8/) average carrier populations, respectively. The distributions of avalanches with intermediate populations n~/spl epsi/(10/sup 5/, 10/sup 8/) that exhibit peculiar convex shapes have not been considered as regular distributions so far. They have been regarded as an experimental artefacts causing deviations from the regular exponential law. On the basis of refined experiments we argue for a new interpretation of those peculiar distribution curves. They have proved to be independent of the remaining two regular statistics and manifest a new distribution law well approximated by the Pareto distribution. The basic physics underlying this separate statistical distribution is intimately related to the inner space charges formed inside the avalanches with higher carrier populations. The inner space charges that modify the local intensity of the electric field and result in redistribution of populations and manifestation of a new statistical behavior.  相似文献   
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