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排序方式: 共有323条查询结果,搜索用时 156 毫秒
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《Food Control》2006,17(8):631-636
Recently, DNA-based techniques became very common for the detection of genetically modified organisms (GMOs) in food products. For rapid and easy detection of GMOs, polymerase chain reaction (PCR) screening methods, which amplify common transgenic elements, are applied in routine analysis. Incorporation of PCR and membrane method introduced in this study offer an alternative detection of GMOs. In this study, a total of 32 samples and three certified reference materials were tested for the existence of the 35S promoter of cauliflower mosaic virus (CaMV) and 5-enol-pyruvyl-shikimate-3-phosphate synthase (EPSPS) gene residues. Dot blot screening system introduced in this study can be routinely used as a semi-quantitative screening of GMOs. 相似文献
3.
In a bending load test for brittle materials, such as ceramics for spacecraft and aircraft, decreasing the number of test specimens required is a crucial problem. This paper discusses the effectiveness of using the information of both fracture stress and fracture location to decrease the number of specimens required to obtain the same precision as the Weibull estimator. The following results were obtained: It was found that by adding the fracture location information, the precision of the Weibull parameter estimation under the optimal design became 1.5–1.9 times better compared with the case of using only the fracture stresses. This means the number of samples necessary to attain the same precision becomes 1/1.5–1/1.9. Tables and figures which give information on the number of samples necessary to attain the required precision are given. 相似文献
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On the atmospheric pressure operation of secondary electron emission gaseous X-ray imaging detectors
A. Breskin R. Chechik I. Frumkin 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1996,380(3):562-567
Radiation-induced low-energy secondary electrons multiplied in gas by a series of wire electrodes provide an efficient means for fast and accurate radiation localization under very high flux. We discuss here the properties of secondary electron emission (SEE) X-ray detectors, operated at atmospheric pressure helium-based mixtures. 相似文献
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文章总结了我国制造业信息化现状,建立了具有质量、成本、时间等3维质量要素框架及基于信息集成的质量创新框架模型;探讨了管理创新的主要内容和技术创新的关键技术;结合案例,分析了质量创新绩效及其评价方法。 相似文献
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R. Pandiselvam M.R. Manikantan V. Divya C. Ashokkumar R. Kaavya Anjineyulu Kothakota 《臭氧:科学与工程》2019,41(6):491-507
ABSTRACTOzone processing is one of the encouraging non-thermal and bio-friendly techniques in the food processing sector. The applicability of ozone technology in food industry is increasing due to its antimicrobial action and modification of functional properties of the foods. The structural modifications of starches have major applications in the food and bakery industry for producing products with increased shelf life, improved texture, and retention of moisture content. The positive response of ozonation in carboxyl and carbonyl group alters the viscosity of starch molecules. Rheological characteristics like low viscosity even at an increased concentration, desirable binding properties, and film-forming ability have increased its use in the food processing industry. The influence of ozonation in the physicochemical properties is mainly retrogradation and cross-linking of amylose and amylopectin molecules and enzymatic modifications. Ozonation cause change in crystallinity, viscosity, expansion ratio, and gelatinization temperatures. Finally, ozonation induces many possible changes in native starches for the effective utilization in the processing sectors. In this review, starch modifications utilizing ozone and various research achievements and scientific reports focusing on the effect of ozonation in terms of physical, chemical, and thermal properties of native starches and on the possible modifications have been summarized and discussed. In conclusion, ozone is a green technology that can be effectively used as an alternative oxidation technique for starch modification. 相似文献
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在对机车转向架螺旋锥齿轮的粗、精加工中发现其表面鼓起许多小泡,将其剖开酸洗后呈现为小裂纹状,该现象在实际生产中较为罕见,对此进行分析,探讨,查找原因,确定这是钢材内气泡未能焊合的结果,为此制定了改进措施。 相似文献
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Dynamic grey model of verification cycle and lifecycle of measuring instrument and its application 总被引:2,自引:0,他引:2
Two dynamic grey models DGM (1, 1) for the verification cycle and the lifecycle of measuring instrument based on time sequence
and frequency sequence were set up, according to the statistical feature of examination data and weighting method. By a specific
case, i. e. vernier caliper, it is proved that the fit precision and forecast precision of the models are much higher, the
cycles are obviously different under different working conditions, and the forecast result of the frequency sequence model
is better than that of the time sequence model. Combining dynamic grey model and auto-manufacturing case the controlling and
information subsystems of verification cycle and the lifecycle based on information integration, multi-sensor controlling
and management controlling were given. The models can be used in production process to help enterprise reduce error, cost
and flaw.
Foundation item: Project (70272032) supported by the National Natural Science Foundation of China 相似文献