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51.
A cancer activated protein-inorganic nanoparticle was used as breast cancer cell turn-on fluorescence sensor and NIR activated attenuator. 相似文献
52.
Designs, Codes and Cryptography - The (Euclidean) hull of a linear code is defined to be the intersection of the code and its Euclidean dual. It is clear that the hulls are self-orthogonal codes,... 相似文献
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用小角X-射线散射法(SAXS),广角X-射线衍射法(WXAD)和差示扫描量热法(DSC)对由N-催化剂催化聚合的聚丙烯结晶行为进行探讨。发现这种聚丙烯结晶中有β晶型存在,且其含量随结晶时间增加而增加随结晶温度升高而降低;β晶含量增加,聚合物的长周期也会增加,β晶对长周期的影响比α晶更大。乙烯共聚改性后的聚丙烯因分子链规整性下降而阻止了β晶的形成。在熔融状态下结晶时,β晶的形成要求聚丙烯的分子链具有更高的规整性。这些实验结果均从分子链段结晶机理得到了解释。 相似文献
55.
高锰酸钾与乙酰丙酮快速反应动力学 总被引:2,自引:0,他引:2
乙酰丙酮CH_2(COCH_3)_2(简写为Hacac)是重要的有机合成中间体,也是柠檬酸在人体内代谢的中间物.为了进一步掌握柠檬酸氧化的后续变化,我组观测了前人未曾报导过的乙酰丙酮与高锰酸钾在酸性介质中的快速反应.该反应从现象上可明显分为两个阶段:第一个阶段是MnO_4~-的紫色迅速消褪,反应体系转变为浅绿色溶液;第二阶段是浅绿溶液缓慢转变为无色.其中第一阶段的反应速率相当快.我组曾研制成功CFF-751G 型连续流动法快速反应装置,本工作采用该装置对上述第一阶段的快速反应进行了动力学研究. 相似文献
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We investigate the metric generalized inverses of linear operators in Banach spaces and their homogeneous selections, which
was the research suggestion given by Nashed and Votruba (Bull. Am. Math. Soc. 80:831–835, 1974). We construct a kind of the bounded homoneneous selections for the set-valued metric generalized inverse. Criteria for the
metric generalized inverses of linear operators and their homogeneous selections are given in terms of Moore–Penrose conditions.
The research was supported in part by the National Science Foundation Grant (10671049) and the Science Foundation Grant of
Heilongjiang Province. 相似文献
58.
We present a conceptual framework for understanding and formulating ion transport in concentrated solutions, which pictures the ion transport as an ion-vacancy coupled charge transfer reaction. A key element in this picture is that the transport of an ion from an occupied to unoccupied site involves a transition state which exerts double volume exclusion. An ab initio random walk model is proposed to describe this process. Subsequent coarse-graining results in a continuum formula as a function of chemical potentials of the constituents, which are further derived from a lattice-gas model. The subtlety here is that what has been taken to be the chemical potential of the ion in the past is actually that of the ion-vacancy couple. By aid of this new concept, the driving force of ion transport is essentially the chemical affinity of the ion-vacancy coupled charge transfer reaction, which is a useful concept to unify transport and reaction, two fundamental processes in electrochemistry. This phenomenological model is parameterized for a specific material by the aid of first-principles calculations. Moreover, its extension to multiple-component systems is discussed. 相似文献
59.
Lei Hu Tuzhi Xiong Ran Liu Yuwen Hu Dr. Yanchao Mao Prof. M.-Sadeeq Balogun Prof. Yexiang Tong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(26):6575-6583
In the work reported herein, the electrocatalytic properties of Co3O4 in hydrogen and oxygen evolution reactions have been significantly enhanced by coating a shell layer of a copper-based metal–organic framework on Co3O4 porous nanowire arrays and using the products as high-performance bifunctional electrocatalysts for overall water splitting. The coating of the copper-based metal–organic framework resulted in the hybridization of the copper-embedded protective carbon shell layer with Co3O4 to create a strong Cu−O−Co bonding interaction for efficient hydrogen adsorption. The hybridization also led to electronically induced oxygen defects and nitrogen doping to effectively enhance the electrical conductivity of Co3O4. The optimal as-prepared core–shell hybrid material displayed excellent overall-water-splitting catalytic activity that required overall voltages of 1.45 and 1.57 V to reach onset and a current density of 10 mA cm−2, respectively. This is the first report to highlight the relevance of hybridizing MOF-based co-catalysts to boost the electrocatalytic performance of nonprecious transition-metal oxides. 相似文献
60.
An Ambrosetti-Prodi type exact multiplicity result is proved for a diffusive logistic equation with harvesting. We show that a modified diffusive logistic mapping has exactly either zero, or one, or two pre-images depending on the harvesting rate. It implies that the original diffusive logistic equation with harvesting has at most two positive steady state solutions. 相似文献