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221.
Jing Lin CHEN Gang Qiang YIN Zhong Ning CHEN* State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Fuzhou 《中国化学快报》2003,(5)
Great attention is currently paid to the synthesis of polynuclear transition metal complexes as well as their photochemical, photophysical, and electrochemical properties. The design of multicomponent systems capable of performing useful light- and/or redox-induced function is of special interest1. The oxo-centered carboxylate-bridge trinuclear ruthenium clusters have been investigated extensively during recent decades because they have remarkable electron-transfer properties, intense visibl… 相似文献
222.
Valerio De Angelis 《Journal of Mathematical Analysis and Applications》2004,294(1):288-293
We prove that the solutions of the non-autonomous Lyness equation xn+1=(xn+bn)/xn−1, bn>0, x0>0, x1>0, are bounded away from zero and infinity if the sequence bn is monotonic. We also give an example to show that the solutions need not be bounded even when the sequence bn attains only two values. 相似文献
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224.
Techniques and Apparatus for Measuring Rotational Core Losses of Soft Magnetic Materials 总被引:1,自引:0,他引:1
In many situations such as the cores of a rotating electrical machine and the T joints of a multiphase transformer, the local flux density varies with time in terms of both magnitude and direction, i.e. the flux density vector is rotating. Therefore, the magnetic properties of the core materials under the rotating flux density vector excitation should be properly measured, modeled and applied in the design and analysis of these electromagnetic devices. This paper presents an extensive review on the development of techniques and apparatus for measuring the rotational core losses of soft magnetic materials based on the experiences of various researchers in the last hundred years. 相似文献
225.
μ子动量谱的精确测量是L3C宇宙线实验最重要的目标之一.事例重建的好坏是该测量的关键,而能量确定的衰变为双μ子的事例是检验重建程序的最好手段.该数据分析利用在2000年中获取的数据作为样本,筛选出了LEP在2000年4月、5月、8月和9月等Z0能量运行期间L3C宇宙线实验数据中记录的Z0→μ+μ-事例数据,得到通过重建程序后动量为45GeV的μ子动量分辨率为(5.4?7±0.25)%. 相似文献
226.
The mobile agent is a fundamental building block of the mobile computing paradigm. In mobile agent security, oblivious transfer
(OT) from a trusted party can be used to protect the agent’s privacy and the hosts’ privacy. In this paper, we introduce a
new cryptographic primitive called Verifiable Distributed Oblivious Transfer (VDOT), which allows us to replace a single trusted party with a group of threshold trusted servers. The design of VDOT uses a novel
technique called consistency verification of encrypted secret shares. VDOT protects the privacy of both the sender and the receiver against malicious attacks of the servers. We also show the
design of a system to apply VDOT to protect the privacy of mobile agents. Our design partitions an agent into the general
portion and the security-sensitive portion. We also implement the key components of our system. As far as we know, this is
the first effort to implement a system that protects the privacy of mobile agents. Our preliminary evaluation shows that protecting
mobile agents not only is possible, but also can be implemented efficiently.
This work was supported in part by the DoD University Research Initiative (URI) program administered by the Office of Naval
Research under grant N00014-01-1-0795. Sheng Zhong was supported by ONR grant N00014-01-1-0795 and NSF grants ANI-0207399
and CCR-TC-0208972. Yang Richard Yang was supported in part by NSF grant ANI-0207399. A preliminary version of this paper
was presented at the DialM-POMC Joint Workshop on Foundations of Mobile Computing in 2003.
Sheng Zhong received his Ph.D. in computer science from Yale University in the year of 2004. He holds an assistant professor position
at SUNY Buffalo and is currently on leave for postdoctoral research at the Center for Discrete Mathematics and Theoretical
Computer Science (DIMACS). His research interests, on the practical side, are security and incentives in data mining, databases,
and wireless networks. On the theoretical side, he is interested in cryptography and game theory.
Yang Richard Yang is an Assistant Professor of Computer Science at Yale University. His research interests include computer networks, mobile
computing, wireless networking, sensor networks, and network security. He leads the LAboratory of Networked Systems (LANS)
at Yale. His recent awards include a Schlumberger Fellowship and a CAREER Award from the National Science Foundation. He received
his B.E. degree from Tsinghua University (1993), and his M.S. and Ph.D. degrees from the University of Texas at Austin (1998
and 2001). 相似文献
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229.
研究了原子化器温度、载气流速、KBH4 浓度等条件对流动注射 氢化物发生 原子吸收光谱法 (FI-HG -AAS)测定硒时的影响。建立了FI-HG -AAS测定大米中硒的分析方法。在优化的工作条件下 ,测定硒的最低检测浓度为 0 3 3 μg·L- 1,线性范围为 0~ 5 0 μg·L- 1,相对标准偏差小于 4% ,加标回收率为 94%~ 1 0 2 %。本法克服了传统的间断氢化物发生 原子吸收光谱法分析速度慢、样品耗量大、操作繁琐且因手工进样在进样速度和进样体积上容易带来误差等缺点。方法操作简便、快速 ,灵敏度及自动化程度高 ,已广泛应用于大米及富硒大米中微量硒的测定 相似文献
230.