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排序方式: 共有4113条查询结果,搜索用时 31 毫秒
981.
Study on the photosynthetic performances of Enteromorpha prolifera collected from the surface and bottom of the sea of Qingdao sea area 总被引:1,自引:0,他引:1
LIN APeng WANG Chao QIAO HongJin PAN GuangHua WANG GuangCe SONG LiYun WANG ZhiYuan SUN Song & ZHOU BaiCheng Institute of Oceanology Chinese Academy of Sciences Qingdao China Graduate School Beijing College of Marine Science Engineering Tianjin University of Science & Technology Tianjin 《科学通报(英文版)》2009,(3)
In this work, the photosynthetic performances of Enteromorpha prolifera thalli collected from the sur- face and bottom of the sea of Qingdao sea area were studied with chlorophyll fluorescence and oxy- graph technology. The samples with the highest photosynthetic activity among their kinds, the floating thalli from the sea surface of the south of the Qingdao Olympic Sailing Center and the sedimentary thalli from the mud surface of the bottom Tuandao bay, were chosen as representatives of surface thalli and ... 相似文献
982.
OU XiuQin XU ShengZhao LIANG GuangChuan WANG Li & ZHAO Xia Institute of Power Source & Ecomaterials Science Hebei University of Technology Tianjin China 《中国科学:技术科学》2010,(4)
Lithium iron phosphate(LiFePO4)was synthesized from LiOH,FeSO4 and H3PO4 by a hydrothermal process at 180℃.The samples were characterized by X-ray diffraction,scanning electron microscopy and chemical analysis.Electrochemical performance of the samples was tested in terms of charge-discharge capacity and cycling behavior.The results indicated that Fe(Ⅲ) impurity had obviously effect on the electrochemical properties of LiFePO4,and the formation of Fe 3+ was caused by the oxidation of Fe 2+ in the dissolving... 相似文献
983.
好氧微生物处理在三元复合驱采出水表现出较好的应用前景,在油田实际污水处理过程中,要求能够尽量的回收原油,减少微生物对水中剩余原油的降解.研究采用已驯化好氧生物载体填料,通过原水的室内试验,考察微生物降解石油过程中,将原油用于自身代谢底物和将原油回收的比率.研究表明,164.53 mg/L的采出水中原油,约12%的原油被微生物吸收利用,80%原油被回收,同时还有约5%~8%处理过程中被挥发和损耗;如果污水处理工艺中,采用气浮装置进行原油的回收,微生物将原油用于自身转化利用率为5%.结果表明在污水处理过程中,好氧微生物作为一种生物催化剂,其维持自身生存所利用的原油较少,而用于三元污水的深度处理上具有很好的处理效果. 相似文献
984.
Search engine is an effective approach to promote the service quality of the World Wide Web. On terms of the analysis of search engines at home and abroad, the developing principle of search engines is given according to the requirement of Web information for chemical fiber engineering. The implementation method for the communication and dynamic refreshment of information on home page of the search engines are elaborated by using programming technology of Active Server Page 3.0 (ASP3.0). The query of chemical fiber information and automatic linking of chemical fiber Web sites can be easily realized by the developed search engine under Internet environment according to users' requirement. 相似文献
985.
级化学系化学教育专业课题组 《平顶山学院学报》2001,16(Z1):80-82
实施素质教育的关键在教师,高素质的教育队伍,是高质量教育的基础.未来教师的素质,直接影响到教育的水平和质量.因此,了解当前初中化学教学现状,是搞好素质教育,培养高素质化学教师的前提和保障. 相似文献
986.
An efficient adaptive group of pictures(GOP)-Ievel bit allocation algorithm was developed based on reverse dynamic programming(RDP).The algorithm gives the initial delay and sequence distortion curve with just one iteration of the algorithm.A simple GOP-level rate and distortion model was then developed for two-level constant quality rate control.The initial delay values and the corresponding optimal GOP-level bit allocation scheme can be obtained for video streaming along with the proper initial delay f... 相似文献
987.
提出了一种闭环辨识和2自由度控制器组结合的设计方法,从前馆控制器和反馈控制器两方面,根据预测误差,适当地选择辨识对象和加权函数,闭环辨识与控制器设计相结合,仿真结果证实,辨识容易,设计简单,方法有效。 相似文献
988.
The present research brings new insights on the role of admixed corrosion inhibitors in the processes of cement hydration and rebar corrosion.The admixing of NaCl and the corrosion inhibitors in fresh mortar was found to alter the morphology and microstructure of the hardened mortar at the steel-mortar interfacial region.The admixing of the inhibitors increased the risk of carbonation of cement hydrates at the steel-mortar interfacial region,but partially displaced chloride ions. Chloride and the admixed in... 相似文献
989.
巫径 《西昌学院学报(自然科学版)》2001,(4)
酶作为一种生物催化剂,在生命活动中起着重要作用,饲用酶制剂是经基因工程技术筛选出的细菌或真菌菌株的发酵产物。作为一种纯天然饲料添加剂已在充分利用各种粮食资源和提高畜禽肉质上展示出广泛的运用前景。本文在介绍饲用酶制剂种类、生产工艺、作用效果的基础上,综述了其研究运用的情况,并展望饲用酶制剂研究的发展趋势。 相似文献
990.
WEPPNER Werner 《科学通报(英文版)》2009,(8)
Solid lithium ion conducting electrochemical cells using LiSiPO as solid electrolyte and Li2CO3 mixed with Au as electrodes were prepared and employed as chemical sensors for the detection of CO2 gas.The EMF of the cell depends on the concentration of CO2 in air according to the partial pressure dependence of Nernst's law in the investigated range from 100 to 2000 ppm over the temperature range from 473 K to 673 K. 相似文献