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51.
Carbonaceous materials can accelerate extracellular electron transfer for the biotransformation of many recalcitrant, redox-sensitive contaminants and have received considerable attention in fields related to anaerobic bioremediation. As important electron shuttles(ESs), carbonaceous materials effectively participate in redox biotransformation processes, especially microbially-driven Fe reduction or oxidation coupled with pollutions transformation and anaerobic fermentation for energy and by-pro...  相似文献   
52.
Butyl 3,5-ditert-butyl-4-hydroxybenzoate (BB), octyl 3,5-ditert-butyl-4-hydroxybenzoate (OB), and dodecyl 3,5-ditert-butyl-4-hydroxybenzoate (DB) were synthesized and characterized, and their performance as antioxidant for polypropylene (PP) were also investigated. The thermooxidative stability of PP with different antioxidants were assessed by the measurements of long-term accelerated aging, differential scanning calorimetery, and thermogravimetric analysis. The results showed that 3,5-ditert-butyl-4-hydroxybenzoates could effectively inhibit the oxidation degradation of PP. And it was also found that the antioxidant efficiency of BB, OB, and DB for PP was in the order of DB > OB > BB.  相似文献   
53.
We establish a geometric quantization formula for Hamiltonian actions of a compact Lie group acting on a non-compact symplectic manifold such that the associated moment map is proper. In particular, we give a solution to a conjecture of Michèle Vergne. To cite this article: X. Ma, W. Zhang, C. R. Acad. Sci. Paris, Ser. I 347 (2009).  相似文献   
54.
Chemo-enzymatic cascade processes are invaluable due to their ability to rapidly construct high-value products from available feedstock chemicals in a one-pot relay manner. However, they have proven to be challenging because of the mutual inactivation of both catalysts. A conceptually novel strategy based on Pickering interfacial catalysis (PIC) is proposed here to address this challenge. This study aimed to construct a protein-stabilized Pickering system for biphasic cascade catalysis, enabled by phosphorylated zein nanoparticles (ZCPOPs) immobilized in gold nanoparticles (Au NCs). Ultra-small Au NCs, 1–2 nm in diameter, were integrated into ZCPOPs at room temperature. Then, the as-synthesized ZCPOPs–Au NCs were used to stabilize the oil-in-water (o/w) Pickering emulsion. Besides their excellent catalytic activity and recycling ability in a variety of oil phases, ZCPOPs–Au NCs possess unpredictable catalytic activity and exhibit mimicking properties of horseradish peroxidase. Particularly, the cascade reaction is well achieved using a metal catalyst and a biocatalyst at the oil–water interface. The result showed that such a combination of chemo- and biocatalysis improved the catalytic yield more than two times compared with that of sole metal catalysis. This study opened a new avenue to design nanomaterials using the combination of chemo- and biocatalysis in a Pickering emulsion system for multistep syntheses.

A robust chemo- and biocatalytic cascade PIC with a recovery catalyst and a separation product was developed. The results groundbreakingly highlighted the preliminary applications of artificial enzymes and bio-enzymes in a one-pot cascade PIC.  相似文献   
55.
采用固相萃取-高效液相色谱法测定水中呋喃丹浓度,对测量结果的不确定度进行了评定。根据《测量不确定度评定与表示(》JJF 1059-1999)中有关规定,建立呋喃丹不确定度分析数学模型。结果表明,该方法测量结果不确定度的主要来源为标准溶液的配制、定容和重复性测试,当水样中呋喃丹的浓度为0.03 mg/L时,扩展不确定度为0.0044 mg/L(k=2)。  相似文献   
56.
Methoxyacrylate fungicides which came from natural product have an excellent,broad spectrum of activities, highly safety and selective to target because of their unique mode of action-inhibit mitochonidrial respiration by blocking electron transfer between cytochrome b and cytochrome c1, so more attention was paid by many companies in agrochemicals and at least 300 patents was applied until now. For the action of blocking electron transfer,some one suggests this kind of chemicals should not only work on fungi,but also on insects (sure) and weeds. Up to now,no herbicidal activity was reported. So the following compounds Ⅰ (X=O,NR,in patent:X=O,S rarely X=N) were designed and synthesized by introduced some fragment of herbicide.  相似文献   
57.
一种节状纳米碳纤维的CVD生长   总被引:1,自引:0,他引:1  
介绍了以发泡Ni为催化剂、用CVD法生长节状纳米碳纤维的工艺过程,讨论了工艺参数对生成榈的产率和形貌的影响,同时还探讨了该样品的生长机理,认为催化剂的不同晶面分别有利于烃类气体的吸附解离或碳的沉积,因此催化剂颗粒的原始形貌影响了不同形貌的碳纤维生长。  相似文献   
58.
在笔者实验室发表于J.Org.Chem.的论文(本文参考文献[12])中提出的芳香胺离子与腺苷反应所得到非常特殊的亚胺加成物的生成机理指出,腺嘌呤对4-联苯胺离子中对位碳原子初始进攻是得到非常特殊的亚胺加成物的最可行生成路径,而腺嘌呤对4-联苯胺离子中邻位碳原子初始进攻的其它3个反应路径,由于涉及几个氢转移过程的反应的能垒较高,所以,理论上讲,它们是不能发生的.但是,研究发现,如果在这些氢转移过程中有水作为媒介,它们的能垒会大大的降低,从而可能使腺嘌呤对4-联苯胺离子中邻位碳原子初始进攻的3个反应路径成为对对位碳原子初始进攻路径的竞争性反应路径.  相似文献   
59.
以实验室养殖的幼小大菱鲆和养殖场养殖大菱鲆幼鱼为研究对象,研究了转牙鲆生长因子基因集胞藻作为饲料添加剂对鱼类血液生理生化指标和红细胞微核率及核异常率的影响。研究结果显示,转基因集胞藻对大菱鲆血液红细胞和白细胞数量、血红蛋白含量及红细胞体积没有影响(p〉0.05);1.0%添加剂量没有引起血清转氨酶活性及碱性磷酸酶和乳酸脱氢酶活性增加(p〉0.05),实验组血清蛋白质、葡萄糖、甘油三脂、胆固醇、尿素氮和肌酐含量以及钾、钠、氯、磷浓度与对照组之间也不存在显著性差异(p〉0.05);转基因集胞藻对红细胞微核及核异常没有诱导作用。结果表明转基因集胞藻不会引起大菱鲆组织器官损伤,也没有遗传毒性,是一种安全的转基因饲料添加剂,可以用作大菱鲆促生长剂使用。  相似文献   
60.
We study the asymptotic of the spectrum of the Dirac operator on high tensor powers of a line bundle. As application, we get a simple proof of the main result of Guillemin–Uribe [13, Theorem 2], which was originally proved by using the analysis of Toeplitz operators of Boutet de Monvel and Guillemin [10]. Received: 6 June 2001; in final form: 18 September 2001 / Published online: 28 February 2002  相似文献   
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