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11.
This is the second of two articles by the same author arguing against the thesis that there was a conspiracy between the Byzantine emperors and Saladin, sultan of Egypt and Syria, against the crusader states and the Third Crusade in the 1180s. While the focus of the first article was primarily on the Latin sources, the present study shifts the focus to the Arabic primary material, hitherto largely neglected or inadequately treated by modern historians. Through a critical re-examination and re-interpretation of the Arabic sources, backed by the introduction and discussion of new Latin material when necessary, this article presents expanded arguments on the relations between the Byzantine Empire, the Sultanate of Konya and Saladin in the 1180s. The conclusions lend further support to the view that the Byzantine rulers and Saladin never concluded an alliance against the Latin settlers of Outremer and the Third Crusade.  相似文献   
12.
在pHl0的NH3-NH4C1缓冲溶液中,Cu(Ⅱ)-头孢唑啉钠络合物在单扫描示波极谱仪上产生一灵敏的还原峰,其一次导数峰电位为-0.30V(vs.SCE),峰电流与铜浓度在0.005—0.3mg/L范围内呈线性关系,检出限为0.0025mg/L。将该波用于人发及硫酸镍中铜含量的测定,并就极谱波的性质进行了探讨。  相似文献   
13.
14.
在甲醇水混合溶剂中合成了标题配合物Cu2(-αfuroic acid)4(H2O)4,测定了其晶体结构,晶体属单斜晶系,空间群P2(1)/c,晶胞参数:a=1.0106(4)nm,b=1.046(6)nm,c=2.00790nm;β=91.118(8)°,V=2.646(2)nm3,Dc=1.619g/cm3,Z=4,F(000)=1306.最终偏离因子R1=0.0567,wR2=0.1676,两个Cu(II)由四个呋喃甲酸根桥联且其端位各有一个水分子配位,形成一个具有畸变的四角锥形配位环境。配合物中Cu(II)-Cu(II)间具有一对称中心,其Cu(II)-Cu(II)的间距为0.2637nm,结合晶体结构对配合物进行了电化学性质研究。  相似文献   
15.
图书馆期刊具有连续性、动态性以及数量多等特点,这给图书馆期刊订购和管理带来一定难度。在信息化时代下,利用Excel和ILAS II系统中的连续出版物子系统进行期刊订购和管理,可以提高工作效率,减少重订、漏订等现象发生。  相似文献   
16.
This paper illustrates a teaching technique used in computer applications in chemical engineering employed for designing various unit operation processes, where the students learn about unit operations by designing them. The aim of the course is not to teach design, but rather to teach the fundamentals and the function of unit operation processes through simulators. A case study presenting the teaching method was evaluated using student surveys and faculty assessments, which were designed to measure the quality and effectiveness of the teaching method. The results of the questionnaire conclusively demonstrate that this method is an extremely efficient way of teaching a simulator-based course. In addition to that, this teaching method can easily be generalised and used in other courses. A student's final mark is determined by a combination of in-class assessments conducted based on cooperative and peer learning, progress tests and a final exam. Results revealed that peer learning can improve the overall quality of student learning and enhance student understanding.  相似文献   
17.
This comparative study focuses on three editions of Rose Blanche, Roberto Innocenti's picturebook portrayal of a young girl who discovers a Nazi concentration camp on the outskirts of her German city. The original text, written in French by Christophe Gallaz to accompany Innocenti's illustrations, was translated into English and published in the United States; this text is compared with the British text, rewritten by Ian McEwan, and the German text, translated by Abraham Teuter. An examination of differences in the three texts demonstrates some of the ways in which cultural, aesthetic, national, ideological, pedagogical, and economic issues influence the translation of a children's book.  相似文献   
18.
过渡金属钯催化的Heck反应是碳碳偶联反应中最重要的反应之一.绿色化学是当前化学领域研究的热点和前沿,离子液体是理想的绿色溶剂.近年来在离子液体中进行Heck反应受到广泛关注并取得了一定进展.文巾就近几年离子液体中的Heck反应进行了综述.  相似文献   
19.
Cardiovascular complications are the major cause of morbidity and mortality in diabetic patients. An attempt has been made to evaluate the risk factors for coronary heart disease in type II diabetics. In the present study the levels of fasting and postprandial plasma glucose, total cholesterol, low density lipoproteins, triglycerides were high and the levels of high density lipoproteins were low in the type II diabetics compared to controls. The markers of free radical induced injury i.e. malondialdehyde and nitrite/nitrate were high while total antioxidant status a marker for antioxidant protection against reactive oxygen species was low in diabetics compared to controls. The study therefore suggests the importance of assessing these markers of oxidative stress and antioxidant capacity along with the other routine investigations in diabetic patients for initiating antioxidant therapy in addition to primary and secondary preventive measures to mitigate the devastating consequences of diabetes leading to coronary heart disease.  相似文献   
20.
谢亮 《科技广场》2006,(8):105-106
直接数字频率合成器(DDS)采用的是一种新的频率合成技术,它具有频率分辨率高、频率转换快、相位噪声小等一系列优点。本文根据DDS的基本原理,提出了基于FPGA的DDS设计与实现。利用Quartus II、MATLAB/Simulink、DSP Builder等功能强大的开发工具,分别从不同的角度给出了几种基于FPGA的DDS的实现方式。最后,就这几种实现DDS的方式,对其优缺点进行讨论。  相似文献   
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