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991.
The magnetic properties of magnetosome magnetite are of interdisciplinary interest because magnetosomes are potential carriers of natural remanent magnetization and paleoenvironment, as well as novel nano-biomaterials in biotechnological and biomedical applications. We carried out magnetic and electron transmission microscopy analyses of fresh Magnetospirillum magneticum AMB-1 whole cells and isolated magnetosomes. Results revealed that AMB-1 synthesized single-domain magnetite magneto-somes, which are arra...  相似文献   
992.
Novel N-doped TiO2 (denoted as N-NTA600) was prepared by treating nanotube titanic acid (NTA) in NH3 flow. Its visible light photocatalytic activity,evaluated by decoloration reaction of methylene blue,is higher than that of N-P25(600) prepared by treatment of P25-TiO2 in the same condition. It is suggested that the origin of visible-light photocatalytic activity is single-electron-trapped oxygen vacancy (Vo·) modified by chemisorbed NO.  相似文献   
993.
综述了寻找孢子体自交不亲和雌雄S决定子的过程,以及孢子体自交不亲和中的显隐性关系及其分类,并提出将来自交不亲和研究的方向。  相似文献   
994.
1. Introduction This is the fourth exposition on theAnalytic Hierarchy Process. It is true thatmany decisions we make subconsciously ariseout of our physical and biological needs andderive from the pressure to survive physically.We also make subconsciou…  相似文献   
995.
1 Introduction Science of complexity and complex systems is a relatively new area In wide fields from chemistry, biology, environment, geo-science, climatology to economics and sociology, complexity has been studied from diverse views and understandings Systems science, which could be traced back to Ludwig von Bertalanffy’foundational work on general system theory, plays an active role in complexity studies From system perspectives, relevant concepts often include interaction, feedback, evol…  相似文献   
996.
Much attention has been attracted to organic thin-film field-effect transistors (OTFFETs) in the past decades[1—4]. Because of their lower cost and easier preparation, OTFFETs are considered to be useful in driving liquid crystal displays (LCD) and organic light-emitting diodes (OLED). Furthermore, flexible OTFFETs will be one of the most useful electronic devices for flexible active matrix driving circuits. OTFFETs based on pentacene single crystal have been reported to be of g…  相似文献   
997.
We consider tasks where in order to perform them it is sufficient that one member of a group will know how to do it. We are interested in the effect of task difficulty, and variability of that difficulty, on group performance, and in particular on the marginal contribution of an additional number to the performance of groups of different size. We explore the implications of various stochastic orders over task difficulty and variability. Some intuitive conjectures are shown to be false.  相似文献   
998.
1. Introduction A supply chain is a network composed osuppliers, manufacturers, retailers, etc., whichcooperate to offer a kind of goods or servicesThese supply chain members cooperate andcompete with each other to maximize theiown profits. For example,…  相似文献   
999.
Interestisrapidlyemergingintheexplorationofmetalnanoparticlesforthedetectionofvariouskindsofmolecules.ExcellentexamplesincludeDNAdetectionbycomplimentaryinteractionsofthiol \|containingDNAattachedtogoldnano particles[1] ,potassiumionsensorsbyusing 15 crown …  相似文献   
1000.
A new approach based on the concept of the diversity increment is applied to reconstruct a phylogeny. The phylogeny of the Eutherian orders use concatenated H-stranded amino acid sequences, and the result is consistent with the commonly accepted one for the Eutherians. Foundation item: Supported by the National Natural Science Foundation of China ( 30170214) and the Open Foundation of the State Key Laboratory of Software Engineer, Wuhan University, China. Biography: Shi Feng ( 1966- ), male, Ph. D, Associate professor, research direction: bioinformatics.  相似文献   
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