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1.
1工程情况简介神华煤直接液化项目是世界上第一套煤制油工业化示范装置,位于内蒙古自治区鄂尔多斯市马家塔。该装置的大型设备较多,神华煤直接液化项目大型设备吊装与运输共涉及到44台大型设备。设备的吊装工期为6个月。  相似文献   
2.
The two Cd(II) and Co(II) 2-D frameworks have been prepared by means of self-assemblies of Cd(II) or Co(II) salts and 1-substituted imidazole and terephthalic acid, and structurally characterized by X-ray diffraction analyses. In complex 1 2-D frameworks with rhombic cavity are formed, in which the each top point of rhombus contains one hexa and two heptacoordinated Cd(II). In complex 2 2-D networks with rectangular cavities are formed, and the opposite benzene rings from carboxyls in each rectangular cavity are parallel.  相似文献   
3.
BACKGROUND: Polysaccharides extracted from fungi or algae have shown a variety of medical activities, and the exploitation of polysaccharides for application in pharmacy has been very promising. In this study, the immunomodulatory properties of polysaccharides from Morchella esculenta were investigated to identify immunostimulatory activity and potentially contribute to the therapeutic potential of Morchella esculenta. RESULTS: A water‐soluble polysaccharide, MEP, was obtained from the fermentation broth of Morchella esculenta. Two fractions of this polysaccharide (MEP‐I and MEP‐II) were extracted and purified. High‐performance gel permeation chromatography analysis showed the average molecular weights of two polysaccharides. Structural properties and compositions of these two fractions were examined by Fourier transform infrared and a high‐performance liquid chromatography with an evaporative light scattering detector. Active experiments suggested that the MEP had typical immunostimulatory activity. CONCLUSION: These bioactivity tests showed that the polysaccharides from Morchella esculenta presented significant immune modulating activity, and this finding may offer the basis for the popular use of polysaccharides in functional foods or medicine. Copyright © 2011 Society of Chemical Industry  相似文献   
4.
本文为W波段辐射计设计了一副口径为300mm偏馈反射面天线,天线要求的工作频率为94.5GHz,副瓣电平低于-25dB,交叉极化电平低于-30dB,半功率波束宽度优于1?。文中采用较小偏置角以改善偏置天线的交叉极化特性,采用焦面场匹配法和模比利用法设计了匹配馈源,通过仿真优化设计,得到良好的波瓣等化电平和驻波比。测量结果表明,测量值与理论值吻合,满足辐射计的指标要求。  相似文献   
5.
Surveying instructor and learner attitudes toward e-learning   总被引:2,自引:2,他引:0  
The trend of using e-learning as a learning and/or teaching tool is now rapidly expanding into education. Although e-learning environments are popular, there is minimal research on instructors’ and learners’ attitudes toward these kinds of learning environments. The purpose of this study is to explore instructors’ and learners’ attitudes toward e-learning usage. Accordingly, 30 instructors and 168 college students are asked to answer two different questionnaires for investigating their perceptions. After statistical analysis, the results demonstrate that instructors have very positive perceptions toward using e-learning as a teaching assisted tool. Furthermore, behavioral intention to use e-learning is influenced by perceived usefulness and self-efficacy. Regarding to learners’ attitudes, self-paced, teacher-led, and multimedia instruction are major factors to affect learners’ attitudes toward e-learning as an effective learning tool. Based on the findings, this research proposes guidelines for developing e-learning environments.  相似文献   
6.
对新设计的一种3mm波段辐射计的特性参数进行了测量,辐射计的特性参数包括灵敏度、测温范围以及辐射计中参考负载和定标黑体的辐射温度修正量.由于受国内3mm波段技术的限制,给3mm波段辐射计的设计和测量带来很大的困难.本文采样口面定标方法,在实验室确定了新设计的3mm波段辐射计的特性参数,以保证它的实际使用意义.  相似文献   
7.
Phase-shifting algorithms for electronic speckle pattern interferometry   总被引:2,自引:0,他引:2  
Kao CC  Yeh GB  Lee SS  Lee CK  Yang CS  Wu KC 《Applied optics》2002,41(1):46-54
A set of innovative phase-shifting algorithms developed to facilitate metrology based on electronic speckle pattern interferometry (ESPI) are presented. The theory of a phase-shifting algorithm, called a (5,1) algorithm, that takes five phase-shifted intensity maps before a specimen is deformed and one intensity map after a specimen is deformed is presented first. Because a high-speed camera can be used to record the dynamic image of the specimen, this newly developed algorithm has the potential to retain the phase-shifting capability for ESPI in dynamic measurements. Also shown is an algorithm called a (1,5) algorithm that takes five phase-shifted intensity maps after the specimen is deformed. In addition, a direct-correlation algorithm was integrated with these newly developed (5,1) or (1,5) algorithms to form DC-(5,1) and DC-(1,5) algorithms, which are shown to improve significantly the quality of the phase maps. The theoretical and experimental aspects of these two newly developed techniques, which can extend ESPI to areas such as high-speed dynamic measurements, are examined in detail.  相似文献   
8.
本文提出了邻氨基酚(OAP)-HO-辣根过氧化物酶(HRP)伏安酶联免疫分析体系并用于烟草莅叶病毒(TMV)的测定。本方法以线性扫描二阶导数伏安法检测HRP催化HO氧化OAP的产物,用于HRP测定的检出限为1.5×10mU  相似文献   
9.
In ACISP 2008,the hash family DASH has been proposed by Billet et al.,which considers the design of Rijndael and RC6.DASH family has two variants that support 256-bit and 512-bit output length respectively.This paper presents the first third-party cryptanalysis of DASH-256 with a focus on the underlying block cipher A256.In particular,we study the distinguisher using differential and boomerang attack.As a result,we build a distinguishing attack for the compression function of DASH-256 with 8-round A256 using the differential cryptanalysis.Finally,we obtain a boomerang distinguisher of 9-round A256.  相似文献   
10.
A new Mn(II) complex of MnL2Cl2 (L = azino-di(5,6-azafluorene)-κ2-NN′) was synthesized and utilized as an electrochemical indicator for the determination of hepatitis B virus (HBV) based on its interaction with MnL2Cl2. The electrochemical behavior of interaction of MnL2Cl2 with salmon sperm DNA was investigated on glassy carbon electrode (GCE). In the presence of salmon sperm DNA, the peak current of [MnL2]2+ was decreased and the peak potential was shifted positively without appearance of new peaks. The binding ratio between [MnL2]2+ and salmon sperm DNA was calculated to be 2:1 and the binding constant was 3.72 × 108 mol2 L−2. The extent of hybridization was evaluated on the basis of the difference between signals of [MnL2]2+ with probe DNA before and after hybridization with complementary sequence. Control experiments performed with non-complementary and mismatch sequence demonstrated the good selectivity of the biosensor. With this approach, a sequence of the HBV could be quantified over the range from 1.76 × 10−8 to 1.07 × 10−6 mol L−1, with a linear correlation of r = 0.9904 and a detection limit of 6.80 × 10−9 mol L−1. Additionally, the binding mechanism was preliminarily discussed. The mode of interaction between MnL2Cl2 and DNA was found to be primary intercalation binding.  相似文献   
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