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介绍了工法的起源和发展、含义、分类及编写内容;叙述了工法的编写、开发、推广应用工作有利于企业的技术积累和管理标准化,论述了工法开发已成为施工企业特级资质准入的重要一环,以及工法开发在企业发展中带动企业科技进步、提升企业核心竞争力、提高企业经济效益、促进企业可持续发展的作用. 相似文献
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目的:研究茶枝柑皮多糖对H2O2诱导的PC12细胞氧化损伤的保护作用。方法:MTT法检测细胞存活率,建立H2O2诱导PC12细胞氧化损伤模型。比色法测定细胞内丙二醛(MDA)含量、超氧化物歧化酶(SOD)以及谷胱甘肽过氧化物酶(GSH-Px)的活性。结果:100μmol/L H2O2诱导PC12细胞4h,细胞呈现明显损伤形态,细胞内MDA含量升高,SOD和GSH-Px活性降低。茶枝柑皮多糖可明显改善PC12细胞损伤,显著降低细胞MDA含量,极显著提高SOD和GSH-Px活性。结论:茶枝柑皮多糖对H2O2诱导PC12细胞损伤具有明显的保护作用,其作用机制可能与提高PC12细胞的抗氧化酶活性有关。 相似文献
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以‘秦美’猕猴桃果实为试材,于盛花期后28 d分别采用0(对照,清水)、5、10、20 mg/L 4 个质量浓度的氯吡脲(1-(2-chloropyridin-4-yl)-3-phenylurea,CPPU)溶液进行蘸果处理,蘸果时间3~5 s,研究采前CPPU处理对‘秦美’猕猴桃贮藏期间果实硬度及细胞壁降解酶活力的影响。结果表明:CPPU处理加速了果实硬度、原果胶和纤维素质量分数的下降,提高了可溶性果胶质量分数及多聚半乳糖醛酸酶(polygalacturonase,PG)、果胶甲酯酶(pectin methylesterase,PME)、纤维素酶(cellulase,Cx)和β-半乳糖苷酶(β-D-galaetosidase,β-Gal)细胞壁降解活力。各处理组果实硬度与可溶性果胶质量分数和PG、Cx活力呈极显著负相关(P<0.01),与原果胶、纤维素质量分数呈极显著正相关(P<0.01);20 mg/L CPPU处理组果实的β-Gal活力与硬度呈显著负相关(P<0.05)。CPPU处理提高了果实细胞壁降解酶的活力,促进了细胞壁的降解,加速了贮藏期间果实的软化,降低了果实的耐贮藏性。为维持猕猴桃采后果实硬度,延长贮藏期,生产中不宜使用CPPU处理,或使用的质量浓度不宜超过5 mg/L。 相似文献
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《Drug development and industrial pharmacy》2013,39(11):1272-1281
The aim of this work was a preliminary study of the “in-process” amorphization of clopidogrel hydrogensulfate (CLP) as model drug during the production of tablets as dosage form. A solvent method was used for amorphization and the crystalline phase of CLP was detected by differential scanning calorimetry; the physical parameters of fresh and stored tablets were investigated. For the amorphous form, Aerosil 200 was selected as crystallization inhibitor as the most suitable of eight auxiliary agents. The optimum composition of the product for amorphization in the scaling-up process (100-fold) was 7 parts of CLP to 3 parts of Aerosil 200. In this scaled-up product, the amorphous CLP was fixed on the surface of microcrystalline cellulose. The tablet form further stabilized the amorphous form. Finally, the steps of an “in-process” amorphization are given as a protocol, which can promote stabilization of an amorphized active pharmaceutical ingredient. 相似文献
6.
《Food Control》2014
During validation and verification of the system for the proper implementation of HACCP principles, it is essential to rely on microbiological data. Considerable science research has been carried out during the last twenty years on sampling and testing of carcasses for hygiene criteria. This includes the preferable indicator microorganisms to be used, in order to indicate the general hygiene of slaughtering procedures, the evaluation of microbiological data gathered and the sampling methods. Furthermore, European Union (EU) and the United States have adopted the procedures for HACCP validation and verification in their legislation. The aim of this review is to demonstrate the relevant modern trends in this field of food science. In conclusion, microbiological data based on the indicators should be interpreted only to assess general trends in the hygiene process of the operator in order to take corrective action. Microbiological results, obtained only at the end of the slaughtering process, do not provide information on the cause of the problem. Therefore, ‘process-based’ microbiological criteria which are based on values measured at various stages of the process, including final carcass values, should be used. Finally, in order to implement an adequate monitoring system, non-destructive techniques of carcass sampling could be used instead of excision. The microbial recovery may be lower, but it is proportional to the excision recovery and therefore, non-destructive techniques, like swabbing with sponges, could be a practical sampling method for the estimation of indicators during the slaughtering procedure and hygiene evaluation. 相似文献
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Blake Fitzpatrick 《History of Photography》2013,37(2):176-187
This article examines the recirculation of Robert Del Tredici's photographs of the Cold War nuclear weapons complex. Originally published in his groundbreaking book, At Work in the Fields of the Bomb (1987), a number of Del Tredici's photographs have been republished in a series of post‐Cold War US Department of Energy reports. The article examines the post‐Cold War circulation of Del Tredici's images in these official government reports and analyzes shifts in their meaning across different historical periods. Ultimately, this paper raises questions about the critical stance of Del Tredici's photographs as they are republished in government reports and examines ways in which the meaning of his photographs responds to both Cold War and post‐Cold War contexts. 相似文献
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Though condensed between the stages of design and completion, the conventional process of designing a building is time consuming, involving various stakeholders, planning processes and a wide team of consultants and contractors. What happens, though, if the time period of an architect's involvement is expanded? How might a more process-orientated approach shift the role of the architect? Tobias Armborst, Daniel D'Oca and Georgeen Theodore , principals of Interboro Partners in New York, describe how they have developed projects that have sought opportunities in expanding the timescale and remit of traditional practice. 相似文献