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1.
压力实时监测法在管道泄漏检测中的应用 总被引:2,自引:0,他引:2
检测输油管道漏油的方法很多,介绍了通过压力实时监测确定输油管道漏油点方法,以及实际应用情况。实践证明,通过压力实时监视确定输油管道漏油点的方法在实际输油运行中是切实可行的。 相似文献
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本研究以深层发酵灵芝为原料,评估灵芝发酵产物对感染猪圆环病毒-2(PCV-2)断奶仔猪生长发育及免疫功能的影响.试验1:选择160头21 d断奶的仔猪,随机分为4组,每组4个重复,每个重复10头猪.各组分别在基础日粮中添加0、50、100和150 mg/kg灵芝发酵产物.试验2:将120头21 d断奶的仔猪随机分为2组... 相似文献
4.
Zong-Qing Huo Feng Zhu Xing-Wang Zhang Xiao Zhang Hong-Bao Liang Jing-Chun Yao Zhong Liu Gui-Min Zhang Qing-Qiang Yao Guo-Fei Qin 《Marine drugs》2022,20(5)
Flexible marine natural products (MNPs), such as eribulin and bryostatin, play an important role in the development of modern marine drugs. However, due to the multiple chiral centers and geometrical uncertainty of flexible systems, configuration determinations of flexible MNPs face great challenges, which, in turn, have led to obstacles in druggability research. To resolve this issue, the comprehensive use of multiple methods is necessary. Additionally, configuration assignment methods, such as X-ray single-crystal diffraction (crystalline derivatives, crystallization chaperones, and crystalline sponges), NMR-based methods (JBCA and Mosher’s method), circular dichroism-based methods (ECCD and ICD), quantum computational chemistry-based methods (NMR calculations, ECD calculations, and VCD calculations), and chemical transformation-based methods should be summarized. This paper reviews the basic principles, characteristics, and applicability of the methods mentioned above as well as application examples to broaden the research and applications of these methods and to provide a reference for the configuration determinations of flexible MNPs. 相似文献
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总结分析了兽用生物制品GMP飞行检查中发现的问题及产生原因,并从强化企业GMP管理理念、提升企业技术能力、加强监管等方面提出了提高兽用生物制品企业GMP管理水平的建议。 相似文献
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包装是展示产品特征、传递产品信息的重要载体,其中呈现的视觉形象、引发的审美体验直接关系到产品的辨识度,影响消费者的购买决策行为.通过分析文化创意视角下开展食用菌产品包装设计的原则,指出文化创意与产品包装设计的融合有利于展示食用菌产品特性,提升产品的审美内涵.从生态健康、情感和文化内涵等角度开展包装设计,使食用菌产品包装... 相似文献
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Colorectal cancer, a malignant tumor with high mortality, has a poor prognosis due to drug resistance and toxicity in clinical surgery and chemotherapy. Thus, finding safer and more efficient drugs for clinical trials is vital and urgent. Natural marine compounds, with rich resources and original chemical structures, are applied widely in anticancer treatments. We provide a systematic overview of recently reported marine compounds such as alkaloids, peptides, terpenoids, polysaccharides, and carotenoids from in vitro, in vivo, and clinical studies. The in vitro studies summarized the marine origins and pharmacological mechanisms, including anti-proliferation, anti-angiogenesis, anti-migration, anti-invasion, the acceleration of cycle arrest, and the promotion of tumor apoptosis, of various compounds. The in vivo studies outlined the antitumor effects of marine compounds on colorectal cancer model mice and evaluated their efficacy in terms of tumor inhibition, hepatotoxicity, and nephrotoxicity. The clinical studies summarized the major chemical classifications and targets of action of the clinical drugs that have entered clinical approval and completed approval for marine anticancer. In summary, we present the current situation regarding the application of natural anti-colorectal cancer marine compounds and prospects for their clinical application. 相似文献
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为探究不同前处理、检测方法对淀粉及其制品中铅含量测定结果的影响,选取淀粉和淀粉制品样品,分别经湿法消解和微波消解处理后,采用国家标准中石墨炉原子吸收光谱法(GFAAS)、电感耦合等离子体质谱法(ICP-MS)和火焰原子吸收光谱法(FAAS)测定铅含量,从方法的回收率、精密度、经济性等方面评估不同前处理、检测方法的推广使用价值。结果表明:两种前处理方法回收率均较好,微波消解法比湿法消解精密度更好;ICP-MS测定的铅含量值显著高于GFAAS(P<0.05),ICP-MS的精密度、回收率较GFAAS更优,样品中的铅含量低于FAAS的检测限,均无法测定;各种淀粉制品中的铅含量普遍高于淀粉。除FFAS外,两种检测方法以及两种前处理方法均符合此类样品的检测要求,可根据精密度要求、实验室条件等选择最佳前处理和检测方法。 相似文献
10.
Ewa Matyjaszczyk 《Pest management science》2019,75(8):2063-2067
Compulsory integrated pest management poses a number of challenges and issues for debate. Some of are discussed with reference to European Union requirements set out in Annex III of Directive 128/2009. Requirements on the use of plant protection products bring with them problems with dose reduction in the light of a resistance prevention strategy, the lack of threshold levels, the necessity of chemical treatments and the limited availability of effective products of biological origin. Use of preventive measures of pest control faces barriers related to profitability and a lack of knowledge on the part of farmers. Challenges to control the system, as well as the fact that some legally enforced rules are not suitable for all crops, seem also to be an issue. © 2019 Society of Chemical Industry 相似文献