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991.
三阶奇异边值问题的多解性 总被引:1,自引:0,他引:1
利用锥上的不动点定理和Green函数的性质,本文在较弱条件下研究了三阶奇异非线性边值问题的多个正解的存在性。 相似文献
992.
不同结构电气石微粉对酸溶液和碱溶液性质的影响 总被引:4,自引:0,他引:4
系统研究了不同结构的电气石微粉因其自发极性和表面吸附与盐酸、NaOH溶液作用对溶液pH值、电导率的影响.用粒径分析仪、扫描电子显微镜、电子能谱仪、X射线衍射仪和红外光谱仪分析不同产地电气石的粒径尺寸、化学成分、晶型结构及其作用原理.用碘量法测定电气石微粉与碱性溶液作用后溶液溶氧量的变化.结果表明:不同产地的电气石微粉由于结构不同产生性能上的差异,它们对溶液pH值、电导率和溶氧量的影响不同.在酸性条件下,内蒙古电气石微粉的作用效果最佳,溶液的pH值由3升至9.在碱性条件下,河北电气石微粉作用效果最好,溶液的pH值由12降至10.电气石微粉可以大幅度提高水的溶氧量.溶液的溶氧量与电气石组分中氧元素的含量有关,氧元素含量越高,溶液中的溶氧量越大. 相似文献
993.
ZHANG Jing-xiao JIN Wei-xing YANG De-qin 《国际设备工程与管理》2006,11(3):158-165
To study the relationship between the evolutions of Chinese Traditional Culture (CTC) and program organization, an outline of the CTC is generalized by reviewing literature, and which is also compartmentalized into two aspects according to economic philosophy views: traditional philosophy aspect and value judgment. Based on three dimensions, which are the philosophy aspect (P), program organization model (P), and value judgment from economic philosophy views ( V), and this evolution sequence, the CTC's influence on the program organization model in the evolution is discussed; then the cultural spatial evolution model for program organization based on the three dimensions (PPV) is constructed. From analyzing the plane matrix of P-P and empirical investigating on the organizational model of construction enterprises, it is found that the ancient Chinese government organizational model still has prevailing influence on the modern program organizational model in China. 相似文献
994.
酸值是衡量食用植物油中游离脂肪酸(free fatty acid, FFA)含量的指标,也是其重要的氧化和质量指标。目前食用油酸值测定方法中最常用的是滴定法,该方法简单、易行,对多数油脂的检测是有效的,但对酸值较低、颜色较深或存在除FFA外干扰成分的油脂检测误差较大,光谱法、电化学法、比色法、色谱法等仪器分析方法可以作为其替代方法,且仪器分析方法具有较好的灵敏度、准确性。为了进一步拓展和创新食用植物油酸值检测的技术与方法,实现各种植物油酸值的快速准确检测,分析比较了食用植物油FFA的产生途径、酸值检测方法的特点、现状,以期为酸值检测方法的改进及新方法的建立提供参考。 相似文献
995.
对华北地区某高大平房仓的稻谷空调控温储藏情况进行了监测研究。结果表明:度夏期间,利用空调控温技术,仓房内空间温度和表层平均粮温可有效控制在22 ℃以下,但同一粮层不同位点温度差异大,在粮堆表层、西墙、南墙附近局部位置粮温仍会出现高于25 ℃的情况。受夏季外界环境高温影响,粮堆中心与侧壁附近温差10 ℃以上,存在“冷心热皮”引起的水分迁移现象。水分和温度在距离粮堆表层和仓房侧壁0.5 m附近易升高,成为霉菌易滋生的重点部位,同时,也是发芽率降低和脂肪酸值易升高的位置。因此,在控温储粮过程中需加强对粮堆表层和仓房侧壁粮情的监控。 相似文献
996.
997.
Nadire
zenver Onat Kadioglu Yujie Fu Thomas Efferth 《International journal of molecular sciences》2022,23(3)
Pigeon Pea (Cajanus cajan (L.) Millsp.) is a common food crop used in many parts of the world for nutritional purposes. One of its chemical constituents is cajanin stilbene acid (CSA), which exerts anticancer activity in vitro and in vivo. In an effort to identify molecular targets of CSA, we performed a kinome-wide approach based on the measurement of the enzymatic activities of 252 human kinases. The serine-threonine kinase WNK3 (also known as protein kinase lysine-deficient 3) was identified as the most promising target of CSA with the strongest enzymatic activity inhibition in vitro and the highest binding affinity in molecular docking in silico. The lowest binding affinity and the predicted binding constant pKi of CSA (−9.65 kcal/mol and 0.084 µM) were comparable or even better than those of the known WNK3 inhibitor PP-121 (−9.42 kcal/mol and 0.123 µM). The statistically significant association between WNK3 mRNA expression and cellular responsiveness to several clinically established anticancer drugs in a panel of 60 tumor cell lines and the prognostic value of WNK3 mRNA expression in sarcoma biopsies for the survival time of 230 patients can be taken as clues that CSA-based inhibition of WNK3 may improve treatment outcomes of cancer patients and that CSA may serve as a valuable supplement to the currently used combination therapy protocols in oncology. 相似文献
998.
Xinyu Dai Yufeng Gu Jinli Guo Lingli Huang Guyue Cheng Dapeng Peng Haihong Hao 《International journal of molecular sciences》2022,23(3)
The purpose of this study was to establish the clinical breakpoint (CBP) of apramycin (APR) against Salmonella in swine and evaluate its effect on intestinal microbiota. The CBP was established based on three cutoff values of wild-type cutoff value (COWT), pharmacokinetic-pharmadynamic (PK/PD) cutoff value (COPD) and clinical cutoff value (COCL). The effect of the optimized dose regimen based on ex vivo PK/PD study. The evolution of the ileum flora was determined by the 16rRNA gene sequencing and bioinformatics. This study firstly established the COWT, COPD in ileum, and COCL of APR against swine Salmonella, the value of these cutoffs were 32 µg/mL, 32 µg/mL and 8 µg/mL, respectively. According to the guiding principle of the Clinical Laboratory Standards Institute (CLSI), the final CBP in ileum was 32 µg/mL. Our results revealed the main evolution route in the composition of ileum microbiota of diarrheic piglets treated by APR. The change of the abundances of Bacteroidetes and Euryarchaeota was the most obvious during the evolution process. Methanobrevibacter, Prevotella, S24-7 and Ruminococcaceae were obtained as the highest abundance genus. The abundance of Methanobrevibacter increased significantly when APR treatment carried and decreased in cure and withdrawal period groups. The abundance of Prevotella in the tested groups was significantly lower than that in the healthy group. A decreased of abundance in S24-7 was observed after Salmonella infection and increased slightly after cure. Ruminococcaceae increased significantly after Salmonella infection and decreased significantly after APR treatment. In addition, the genera of Methanobrevibacter and Prevotella were defined as the key node. Valine, leucine and isoleucine biosynthesis, D-Glutamine and D-glutamate metabolism, D-Alanine metabolism, Peptidoglycan and amino acids biosynthesis were the top five Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways in the ileum microbiota of piglets during the Salmonella infection and APR treatment process. Our study extended the understanding of dynamic shift of gut microbes during diarrheic piglets treated by APR. 相似文献
999.
1000.
关于Vague值转化为Fuzzy值的方法的分析 总被引:6,自引:5,他引:1
提出了Vague值转化Fuzzy值的方法的不可分辩的定义,用此定义证明了四种转化方法的不可分辩性。证明了五种方法(其中有该文提出的三种方法)是较好的转化方法。 相似文献