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排序方式: 共有2316条查询结果,搜索用时 15 毫秒
921.
Brett Trost Susan Walker Zhuozhi Wang Bhooma Thiruvahindrapuram Jeffrey R. MacDonald Wilson W.L. Sung Sergio L. Pereira Joe Whitney Ada J.S. Chan Giovanna Pellecchia Miriam S. Reuter Si Lok Ryan K.C. Yuen Christian R. Marshall Daniele Merico Stephen W. Scherer 《American journal of human genetics》2018,102(1):142-155
922.
923.
Increasing the abscisic acid level in maize grains induces precocious maturation by accelerating grain filling and dehydration 总被引:5,自引:0,他引:5
Li Zhang Xiao-Gui Liang Si Shen Hua Yin Li-Li Zhou Zhen Gao Xin-Yue Lv Shun-Li Zhou 《Plant Growth Regulation》2018,86(1):65-79
Elevated levels of abscisic acid (ABA) are closely associated with cereal grain filling under water deficit. However, grain dehydration during grain filling has received little attention. In this paper, three experiments with drought stress and exogenous ABA treatments were conducted to investigate the relationship between ABA and grain dehydration in maize (Zea mays L.) during the grain-filling period. The results indicated that exogenous ABA application and drought stress led to the same tendency of the grain ABA concentration, carbohydrate concentration and dehydration rate to increase but the moisture content to decrease. Moreover, the time to reach the maximum grain-filling rate was advanced, and the grain-filling period was shortened. In in vitro culture experiments, the sucrose-to-starch conversion was promoted, mainly influenced by sucrose synthase, ADP-glucose pyrophosphorylase (AGPase), and soluble starch synthase during the middle grain-filling stage, and the improvement in starch synthesis was possibly induced by AGPase. Correlation analysis showed that the ABA level was significantly negatively correlated with the moisture content and positively correlated with the starch level. A close and notably negative correlation was observed between the grain moisture content and starch level. In summary, adequate grain ABA promoted sucrose-to-starch conversion, shortened the duration of grain filling and accelerated grain dehydration, resulting in precocious grain maturation. 相似文献
924.
925.
天然甜味剂罗汉果的研究与应用 总被引:12,自引:2,他引:10
本文综述了广西特产药用植物罗汉果的化学成分和药理研究,其甜味成分的甜度与结构关系及提取分离方法和应用。 相似文献
926.
Selection of an extracellular esterase-producing microorganism 总被引:2,自引:0,他引:2
Guillermo R. Castro Adrián O. Stettler Marcela A. Ferrero Faustino Siñeriz 《Journal of industrial microbiology & biotechnology》1992,10(3-4):165-168
Summary The conventional esterase plate-screening technique has been modified in order to obtain a better differentiation of high producing strains. A short exposure to Lugol's iodine solution after colony growth enhanced the contrast between the precipitation halo and the background. Batch cultures of a selected strain characterized as belonging to theBacillus subtilis group showed a high level of extracellular activity at pH 6.6 to 8.0 and 35°C. In crude extracts the optimum enzymatic activity was obtained at 35°C and pH 7.0. 相似文献
927.
Thin‐Film Solar Cells: Atomic‐Scale Observation of Oxygen Substitution and Its Correlation with Hole‐Transport Barriers in Cu2ZnSnSe4 Thin‐Film Solar Cells (Adv. Energy Mater. 6/2016)
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928.
A Layer‐Structured Electrode Material Reformed by a PO4‐O2 Hybrid Framework toward Enhanced Lithium Storage and Stability
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The surface framework of LiCoO2 is modified through a surface treatment called phosphidation, which suppressed the unwanted phase transition occurring above 4.2 V. The surface instability of LiCoO2 toward organic electrolytes is simultaneously improved by changing its surface structure from an O2‐based framework to a PO4‐based framework that can protect against HF attack during cycling. Phosphidated LiCoO2 is successfully synthesized that showed greater stability in its bulk and surface structures. The phosphidated form enables faster Li+ diffusion and prevents irreversible phase transitions, especially when charged above 4.2 V, and consequently demonstrates excellent cycling performance and rate capabilities. The improved kinetics and stability resulting from phosphidation make LiCoO2 highly suitable as a high‐voltage cathode material for use in lithium ion batteries. 相似文献
929.
Young Hoon Oh Gyeong Tae Eom Kyoung Hee Kang Jeong Chan Joo Young-Ah Jang Jae Woo Choi Bong Keun Song Seung Hwan Lee Si Jae Park 《Bioprocess and biosystems engineering》2016,39(4):555-563
Gene-expression cassettes for the construction of recombinant Clostridium beijerinckii were developed as potential tools for metabolic engineering of C. beijerinckii. Gene expression cassettes containing ColE1 origin and pAMB origin along with the erythromycin resistance gene were constructed, in which promoters from Escherichia coli, Lactococcus lactis, Ralstonia eutropha, C. acetobutylicum, and C. beijerinckii are examined as potential promoters in C. beijerinckii. Zymogram analysis of the cell extracts and comparison of lipase activities of the recombinant C. beijerinckii strains expressing Pseudomonas fluorescens tliA gene suggested that the tliA gene was functionally expressed by all the examined promoters with different expression level. Also, recombinant C. beijerinckii expressing C. beijerinckii secondary alcohol dehydrogenase by the constructed expression cassettes successfully produced 2-propanol from glucose. The best promoter for TliA expression was the R. eutropha phaP promoter while that for 2-propanol production was the putative C. beijerinckii pta promoter. Gene expression cassettes developed in this study may be useful tools for the construction of recombinant C. beijerinckii strains as host strains for the valuable chemicals and fuels from renewable resources. 相似文献
930.