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41.
42.
序言本标准是以备注中所示的国际标准为基础,在正文中规定了原日本工业标准中规定的种类、等级和形状、尺寸、品质、检查、产品的称谓及标准,规定了没有变更技术性内容的日本工业标准.但是,在对应的国际标准中没有的项目(检查、产品的称谓及标注),在日本工业标准中进行了补充. 相似文献
43.
AN EXTENDED MODELING OF TIDE-WAVE MOTION 总被引:1,自引:1,他引:0
Zhang Qing hua Xu Hao Qu Yuan yuan First Institute of Oceanography State Oceanic Administration Qingdao China Key Laboratory of Marine Science Numerical Modeling State Oceanic Administration Qingdao China 《水动力学研究与进展(B辑)》2001,(3)
1 . INTRODUCTIONTostudythemotionofthetide waves,theshallowwaterequations ,i.e .theverticalintergra tionofthecontinuityequationandmomentumequa tion ,isconsideredasthegoverningequations.Byaboveequationstwoequationsrelatedtothehorizon talfluxofthetide currentsa… 相似文献
44.
~~Growth of CeO_2, Y_2O_3 Buffer Layers for YBCO Coated Conductor 相似文献
45.
对国产Ru/Al2O3催化剂研制开发、侧线试验及工业化试用情况进行了探讨,为国产Ru/Al2O3催化剂的推广应用提供了依据. 相似文献
46.
Jiang-Li Chen Zhuo Xu Shao-Bo Qu Xiao-Yong Wei Xiao-Hui Liu 《Ceramics International》2008,34(4):803-807
The NiFe2O4 and Pb(Zr0.52Ti0.48)O3 ceramic composites are prepared by conventional solid state reaction method. The microstructural and morphological properties of the composites are studied by X-ray diffraction analysis and scanning electron microscopy. Results indicate that the ferrite and piezoelectric phases can co-exist in the composites. The relationship between the dielectric constant and frequency (40 Hz–40 MHz) as well as temperature is also investigated. It is noted that the transition temperature of the composites is about 380 °C. A double electric hysteresis loop is observed in our composites. The magnetic properties are relatively weak according to the magnetic hysteresis loop. With increase in the content of the ferrite phase, the permeability increases. The electromagnetic properties of the as-prepared composites are tunable according to the content of the NiFe2O4 phase. 相似文献
47.
In this letter, a novel well-defined PPV-b-PMMA rod-coil diblock copolymer, consisting of PPV oligomer as its rod block and PMMA as its coil block, respectively, was prepared via ATRP for the first time. The structure of the copolymer was determined by the measurements of FTIR, 1H NMR and gel permeation chromatography (GPC). The thermal and optical properties of the copolymers are investigated by DSC, TGA, UV-Vis and photoluminescence (PL) spectra. The results showed that, the introduction of PMMA coil block can improve both the thermal stability and optical properties of PPV oligomer. The highly ordered hexagonally honeycomb-structured film of the copolymer fabricated by vaporizing solvent is also investigated by optical microscope and SEM. 相似文献
48.
结合西气东输管道工程燃气轮机驱动压缩机组设备订货及验收中对性能试验项目的确定、工厂试验及见证过程,介绍了燃压机组性能试验项目所涉及的主要内容、执行标准、需要达到的技术指标,各种性能试验的基本情况,买方参加工厂试验见证中需要重点处理好的问题等。以期为我国其他大型长输天然气管道机组订货及试验见证工作提供借鉴。 相似文献
49.
50.
Xin Song Xiaoyu Qi Bin Hao Yinbo Qu 《European Journal of Lipid Science and Technology》2008,110(12):1095-1101
Although lipases are widely applied in a wide variety of reactions, available information on the factors that are responsible for the substrate specificities of lipases from different sources is scarce. In this paper, nine lipase‐producing microorganism strains were isolated from oil‐containing samples. The properties of these enzymes, including pH optima, temperature optima, thermal stability, and pH stability, vary significantly with the different sources from which these lipases were isolated. The substrate specificities of the nine lipases, including fatty acid and positional specificities, were also studied. The fatty acid specificities of the nine lipases were observably different toward 15 substrates with different carbon chain lengths, different saturation degrees and different side chains. The lipases from S3 Penicillium citrinum (PCL), MJ1 Aspergillus niger (ANL), MJ2 Aspergillus oryzae (AOL), YM Bacillus coughing (BCL), S9 Geotrichum candidum (GCL), and S11 Candida lypolytica (CLL) showed the strongest specificities to short‐chain esters, and the other lipases showed strong selectivity for medium‐ or long‐chain and branched esters. The positional specificities were examined by analyzing the hydrolytic products of triolein catalyzed by the nine lipases, using TLC. The lipases can be mainly classified into two groups by their specificities for the ester bond at position 2 of triglycerides; one group can selectively hydrolyze the ester bond at position 2 of the triglycerides, the other group cannot. All these nine lipases were divided into four groups by hierarchical clustering analysis on the basis of the results of fatty acid and positional specificities. 相似文献