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51.
Transient characteristics of organic bulk-heterojunction solar cells have been studied using pulsed laser probing. An analysis of the photoresponse waveforms of a typical solar cell measured by varying load resistance within broad range at different values of the bias voltage provided detailed information on the photocell parameters that characterize electron-transport properties of active layers. It is established that the charge carrier mobility is sufficient to ensure high values of the fill factor (∼0.6) in the obtained photocells. On approaching the no-load voltage, the differential capacitance of the photocell exhibits a sixfold increase as compared to the geometric capacitance. A possible mechanism of recombination losses in the active medium is proposed.  相似文献   
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Studied in the course of a multiple-modality treatment of patients with stage III to IV ovarian cancer were effects of retinol and tocopheroli acetas and enterosorption with a silicone sorbent polysorb on the processes of lipid peroxidation and indices for the antioxidant system, for which purpose 75 female subjects were examined. The results obtained showed that retinol and tocopheroli acetas and enterosorption combined in treatment of patients with stage III-IV ovarian cancer made for stabilization of the processes of lipid peroxidation as well as for normalization of blood plasma content of factors of the antioxidant defence.  相似文献   
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Highly comminuted supracondylar humeral fractures were stabilised in six large-breed dogs with a modified type I external fixator using a craniomedial acrylic connecting column and an intramedullary pin which was incorporated into the connecting frame. This construct provided sufficient stability to allow satisfactory bone healing in five of the six dogs, while premature removal of the intramedullary pin and external fixator resulted in subsequent refracture of the humerus in the remaining dog. Limb function at the time of final assessment was considered excellent in two dogs, good in three dogs and poor in one dog. The craniomedial acrylic connecting column simplified application of this modified type I(a) configuration to the humerus by reducing the number of clamps required; the acrylic column also facilitated contouring of the craniomedial connecting column to the brachium and was readily extended proximally to engage the intramedullary pin. In addition, the acrylic connecting column allowed placement of intramedullary pins of varying diameter.  相似文献   
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The problem of the presence of carcinogens in the environment has become of considerable concern to the public, as it has been to the biomedical community for some time. The burden of identifying carcinogenic agents and determining threshold levels, if they exist, falls upon the scientific community. Particular care must be exercised in the design, conduct and analysis of experiments directed toward the identification of carcinogens. The data generated from such tests provides the basis for regulatory decisions by governmental authorities. The advice provided by scientists must be based on sound data. There have been instances, however, and there will be others, in which biological variability and the limits of sensitivity of our tests will give equivocal results. It is the duty of scientists to bring such uncertainties to the attention of the public while working towards the development of more sensitive and precise techniques.  相似文献   
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本文对采用过二硫酸铵 (NH4) 2 S2 O8法从 Li Mn2 O4中萃取锂离子进行了研究 ,并就所获得吸附剂 (Mn O2 (Li) )的特性 ,特别是对于分离锂同位素的能力进行了测试。在良好的控制条件下 ,(NH4) 2 S2 O8是一种优良的锂吸附剂 ,它具有非常高的锂萃取度 ,同时保持锰的最小溶解性。所制备的 Mn O2 (Li)在 2 5°C时最大的 7Li/ 6Li同位素分离因子为 1 .0 1 4,它是那些商品有机离子交换剂的几倍。  相似文献   
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