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1.
Fan FR  Bard AJ 《Science (New York, N.Y.)》1995,267(5199):871-874
The electrochemical behavior of a single molecule can be observed by trapping a small volume of a dilute solution of the electroactive species between an ultramicroelectrode tip with a diameter of approximately 15 nanometers and a conductive substrate. A scanning electrochemical microscope was used to adjust the tip-substrate distance ( approximately 10 nanometers), and the oxidation of [(trimethylammonio)methyl] ferrocene (Cp(2)FeTMA(+)) to Cp(2)FeTMA(2+) was carried out. The response was stochastic, and anodic current peaks were observed as the molecule moved into and out of the electrode-substrate gap. Similar experiments were performed with a solution containing two redox species, ferrocene carboxylate (Cp(2)FeCOO(-)) and Os(bpy)(3)(2+) (bpy is 2,2'-bipyridyl).  相似文献   
2.
This paper ainalyses the size effect of the fracture energy of concrete tested bythree point bending. It is shown that positive errors of test results of fracture energy increase,ornegative errors decrease with increasing of the specimen ize. The phenomenon is one of main causesresulting in the size effect of fracture energy.  相似文献   
3.
The term Cleaner Production(CP)and Estimation of Cleaner Production Potential are introduced, meanwhile their importance are pointed out. Three kinds of cleaner technologies are put forward-Best Available Technology(BAT), Best Economic Attractive Technology(BEAT), and usually used new technology, combined with some CP casesat home and abroad. several cleaner technologies are compared, and the results show that the implementation of CP can greatly reduce consumption of resource and energy and pollution emission, There are obvious environmental, economic and social benefits. The great potential of CP in industrial pollution control are estimated and demonstrated ultimately.  相似文献   
4.
Based on the fractal theory, using quarter tree in neighborhood method and Bang-Bang control method, the steady control of the chaotic in the secure communication is realized. A simulation circuit has been designed based on driving responding theory, then, its synchronization is simulated on the computer.  相似文献   
5.
In this paper,the axisymmetrical shells of suspension crosssection is studied by means of integral equation in initial parameter form.An example of the shells under uniformly distributed load is calculated.  相似文献   
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7.
Background: Methionine or lysine has been reported to influence DNA methylation and fat metabolism, but their combined effects in N6-methyl-adenosine(m6A) RNA methylation remain unclarified. The combined effects of rumen-protected methionine and lysine(RML) in a low-protein(LP) diet on lipid metabolism, m6A RNA methylation,and fatty acid(FA) profiles in the liver and muscle of lambs were investigated. Sixty-three male lambs were divided into three treatment groups, three pe...  相似文献   
8.
Background The fat deposition has a crucial role in animal meat flavor, and fat deposition-related traits are vital for breeding in the commercial duck industry. Avian fat-related traits are typical complex phenotypes, which need a large amount of data to analyze the genetic loci.Results In this study, we performed a new phenotypic analysis of fat traits and genotyped whole-genome variations for 1,246 ducks, and combed with previous GWAS data to reach 1,880 ducks for following analysis. The carc...  相似文献   
9.
Autophagy is an evolutionarily conserved degradation pathway of lysosomes(in mammals) and vacuoles(in yeasts and plants) from lower yeasts to higher mammals. It wraps unwanted organelles and damaged proteins in a double-membrane structure to transport them to vacuoles for degradation and recycling. In plants, autophagy functions in adaptation to the environment and maintenance of growth and development. This review systematically describes the autophagy process, biological functions, and regulat...  相似文献   
10.
IQ67-domain(IQD) proteins function in plant defense and in organ development. The mechanisms by which they influence cotton fiber development are unknown. In the present study, Gh IQD10 was expressed mainly in the transition period of cotton fiber development, and GhIQD10-overexpression lines showed shorter fibers. GhIQD10 interacted with GhCaM7 and the interaction was inhibited by Ca2+. In in vitro ovule culture, Ca2+rescued the shorter-fiber phenotype of GhIQD10-overexpre...  相似文献   
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