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61.
1.INTRODUCTIONOFTEEPROBLEMInthecourseofinexactinference,factsareexpressedaspi{ti},i=l,2,'',n.Amongthem,piisafactandtiisthetruevalue(05ti51)offacts.Alsowecanunderstandtiisthedegreeofbelieforprobability.Factsareexactwhentiisequalto1;When0相似文献
62.
Fracture surface features of the AL6XN super-austenitic stainless steel fatigued at different stress amplitudes were observed by SEM and quantitatively analyzed by a fractal method.It was found that th... 相似文献
63.
诱导三倍体太平洋牡蛎群体发育过程中三倍体率的变化 总被引:1,自引:0,他引:1
借助染色体计数和流式细胞计数计对6-DMAP处理和冷休克两种诱导方法获得太平洋牡蛎(Crassostrea gigas)三倍体群体在各个发育时期三倍体率进行了系统检测。结果发现,在4-8细胞时期,6-DMAP诱导三倍体率为75%,冷休克诱导三倍体率为50%,在发育至D形幼虫期和答稚贝期,两类三倍体群体的三倍体率均有所下降。如从4-8细胞期发育至稚贝期,冷休克诱导群体下降了53.08%以上,6-DMAP诱导群体三倍体率下降了27.36%。养殖一年后,6-DMAP诱导群体三倍体率仍保持在60%以上,而冷休克诱导群体三倍体率已下降至不足10%。这一结果说明,利用6-DMAP诱导来获得三倍体是比较理想的方法。 相似文献
64.
Yun Xu 《系统科学与信息学报》2006,4(4):711-720
In this paper, a convex programming model for portfolio select with trans- action costs was present, we proved the existence condition of optimal solution, and gave a simple example to the optimal solution. 相似文献
65.
ZHU Ping FAN Yun 《武汉大学学报:自然科学英文版》2005,10(5):813-816
Let R be an integral domain of characteristic zero such that the corresponding group rings have block decompositions. We first prove that the submodule consisting of all the R-valued ξi-symmetric functions of several variables is a symmetry class, where ξi is any block character. Then we present a relationship among certain operators introduced for block character. Then we present a relationship among certain operators introduced for block characters. As a consequence, we obtain a decomposition of an arbitrary R-valued function of several variables. Finally, we describe the symmetry property of such summands and determine all the symmetry classes. 相似文献
66.
As the sole cyanine dye approved by the Food and Drug Administration(FDA), indocyanine green(ICG) has been widely applied in solid tumor and metastases surgical navigation as well as malignant tissue destruction. The great performance of ICG benefits from excellent fluorescent properties in the near infrared region(NIR) and reactive oxygen species(ROS) or hyperthermia effects under irradiation. Nevertheless, some intrinsic limitations, such as unstable optical properties, concentration-dependent... 相似文献
67.
周Yun 《晋中师范高等专科学校学报》2002,19(1):60-61
声乐演唱中噪音的保护是一个不容忽视的问题,在声乐训练中,由于错误的发声法,过度使用噪子以及不重视身心健康,常常会导致噪音疾病的发生,对此我们在训练中应对症下药,使噪音永葆艺术的青春。 相似文献
68.
把有限扩散凝聚集团的实空间重正化群方法推广到广义有限扩散凝聚集团,计算了分数维数及广义维数,所得结果与计算机模拟值很接近. 相似文献
69.
Jun Yang Yuan-hua Lin Bing-shu Guo Ming-shan Wang Jun-chen Chen Zhi-yuan Ma Yun Huang Xing Li 《矿物冶金与材料学报》2021,28(10):1621-1628
The silicon-based material exhibits a high theoretical specific capacity and is one of the best anode for the next generation of advanced lithium-ion batteries (LIBs). However, it is difficult for the silicon-based anode to form a stable solid-state interphase (SEI) during Li alloy/de-alloy process due to the large volume change (up to 300%) between silicon and Li4.4Si, which seriously limits the cycle life of the LIBs. Herein, we use strontium fluoride (SrF2) particle to coat the silicon?carbon (Si/C) electrode (SrF2@Si/C) to help forming a stable and high mechanical strength SEI by spontaneously embedding the SrF2 particle into SEI. Meanwhile the formed SEI can inhibit the volume expansion of the silicon?carbon anode during the cycle. The electrochemical test results show that the cycle performance and the ionic conductivity of the SrF2@Si/C anode has been significantly improved. The X-ray photoelectron spectroscopy (XPS) analysis reveals that there are fewer electrolyte decomposition products formed on the surface of the SrF2@Si/C anode. This study provides a facile approach to overcome the problems of Si/C electrode during the electrochemical cycling, which will be beneficial to the industrial application of silicon-based anode materials. 相似文献
70.
SiCp/Al复合材料界面反应研究现状 总被引:10,自引:0,他引:10
界面反应研究是碳化硅颗粒增强的铝基复合材料研发中的重要研究方向.各国研究者分别从界面反应规律、影响因素、控制途径等方面展开研究.界面反应规律方面研究了Al合金液与SiC颗粒可能存在的界面化学反应、界面反应过程和界面反应模型、界面上的相等;界面反应影响因素方面研究了界面反应与制备工艺过程、参数的关系;界面反应有效控制途径方面研究了、基体合金化、SiC颗粒表面处理、工艺选择与工艺参数控制等.今后的界面反应研究方向为:界面精细结构的研究;界面反应的化学热力学及动力学研究等. 相似文献