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911.
Science Letters:Synergetic effects for p-nitrophenol abatement using a combined activated carbon adsorption-electrooxidation process 总被引:1,自引:0,他引:1
A novel fluidized electrochemical reactor that integrated advanced electrochemical oxidation with activated carbon (AC) fluidization in a single cell was developed to model pollutant p-nitrophenol (PNP) abatement. AC fluidization could enhance COD removal by 22%-30%. In such a combined process, synergetic effects on PNP and COD removal was found, with their removal rate being enhanced by 137.8% and 97.8%, respectively. AC could be electrochemically regenerated and reused, indicating the combined process would be promising for treatment of biorefractory organic pollutants. 相似文献
912.
探析"韩流"文化现象对中国服装市场的影响 总被引:2,自引:0,他引:2
高磊 《武汉科技学院学报》2004,17(6):42-45
本丈通过对”韩流”现象的分析,对韩国的文化背景进行探究,使我们对韩国的企业文化和品牌文化有所了解,并取其所长,为中国服装业的可持续性发展提供有益的借鉴。 相似文献
913.
A basal troodontid from the Early Cretaceous of China 总被引:16,自引:0,他引:16
Troodontid dinosaurs form one of the most avian-like dinosaur groups. Their phylogenetic position is hotly debated, and they have been allied with almost all principal coelurosaurian lineages. Here we report a basal troodontid dinosaur, Sinovenator changii gen. et sp. nov., from the lower Yixian Formation of China. This taxon has several features that are not found in more derived troodontids, but that occur in dromaeosaurids and avialans. The discovery of Sinovenator and the examination of character distributions along the maniraptoran lineage indicate that principal structural modifications toward avians were acquired in the early stages of maniraptoran evolution. 相似文献
914.
空间性是地理学科的重要特征 依据地理空间概念的特点 ,结合地理教学的实际 ,指出了常用软件Mapinfo、powerpoint在地理空间概念教学中的重要作用 相似文献
915.
Signal frequency based self-tuning fuzzy controller for semi-active suspension system 总被引:1,自引:0,他引:1
A new kind of fuzzy control scheme, based on the identification of the signal‘ s main frequency and the behavior of the ER damper, is proposed to control the semi-active suspension system. This method ad-justs the fuzzy controller to achieve the best isolation effect by analyzing the main frequency‘ s characters and inspecting the change of system parameters. The input of the fuzzy controller is the main frequency and the op-timal damping ratio is the output. Simulation results indicated that the proposed control method is very effec-tive in isolating the vibration. 相似文献
916.
于雷 《长春工程学院学报(自然科学版)》2003,4(1):55-57
介绍了"一面两孔"夹具定位实验开发的目的和意义,给出了实验的原理、方法、装置构成以及改进方向. 相似文献
917.
LEI Ming YAO Baoli CHEN Yi HAN Yong WANG Yingli MENKE Neimule ZHENG Yuan WANG Congmin FAN Meigong & CHEN Guofu . State Key Laboratory of Transient Optics Technology Xi抋n Institute of Optics Precision Mechanics Chinese Academy of Sciences Xi抋n China . Technical Institute of Physics Chemistry Chinese Academy of Sciences Beijing China Correspondence should be addressed to Yao Baoli 《科学通报(英文版)》2003,48(15):1548-1550
The optical storage characteristics of a new kind of organic photochromic material棗pyrrylfulgide were experimentally investigated in the established parallel optical data storage system. Using the pyrrylfulgide/PMMA film as a photon-mode recording medium, micro-images and encoded binary digital data were recorded, readout and erased in this parallel system. The storage density currently reaches 3?107 bit/cm2. The recorded information on the film can be kept for years in darkness at room temperature. 相似文献
918.
Difference in metapopulation structure and dynamics of two species of coexistent melitaeine butterflies 总被引:3,自引:0,他引:3
WANG Yifei CHEN Jiejun WANG Rongjiang LEI Guangchun & XU Rumei . Ministry of Education Key Laboratory for Biodiversity Science Ecological Engineering Beijing Normal University Beijing China . College of Life Sciences Peking University Beijing China Correspondence should be addressed to Xu Rumei 《科学通报(英文版)》2003,48(12):1239-1246
Habitat fragmentation has been considered to be the most important cause of the extinction and the loss of bio-diversity[1,2]. With the increase of human activities in re-cent years, natural habitat decreased rapidly and patches became smaller and more isolated[3,4]. This leads to an obvious change of population structure and dynamics of many species. However, some species may persist as metapopulations in seriously fragmented landscapes[5]. Metapopulation theory and methodology is estab-lish… 相似文献
919.
XUShandong LEIShengbin ZENGQingdao WANGChen WANLijun BAIChunli 《科学通报(英文版)》2003,48(8):742-745
An important precursor 4,5-didodecylthiolphthalonitrile (DCP) for synthesis of phthalocyanines (Pcs) and subphthalocyanines (SubPcs) was synthesized and the assembling structure of this molecule on the basal plane of highly oriented pyrolytic graphite (HOPG) surface was characterized using the scanning tunneling microscopy (STM) in ambient conditions. In high-resolution images of the molecules, we found that the arrangement of the cyano groups forms a “head-to-head” configuration to keep the stability of the entire system. The mismatch of the DCP molecules with the substrate lattice has also been observed in the experiment. 相似文献
920.
WANGYutang WENYunyi MANing SHILei 《科学通报(英文版)》2003,48(24):2710-2714
The cardiac protective role of a novel erythro-cyte-derived depressing factor (EDDF) on spontaneous hy-pertensive rats (SHR), calcium overload (CaO) rats and Wistar rats and its mechanism was evaluated. Mean artery pressure (MAP), heart rate (HR) and LVdp/dtmax were measured by physiological recorder. The effect of EDDF on the Ca2+-ATPase activity in myocardial sarcoplasmic reticu-lum (SR) of CaO rats was determined by inorganic phos-phate assay. Calcium transport in myocytes was measured by 45Ca2+ radioactive isotope measurement. The phosphoryla-tion levels of extracellular signal-regulated protein kinases (ERK1/2) in myocardial tissue of SHR and CaO rats were measured by Western blot method. And the ultrastructures of cardiac muscle cells were observed with the transmission electron microscope. The results indicated that EDDF could significantly decrease MAP, HR and LVdp/dtmax in a dose dependent manner (P < 0.05). It seems that the mechanism might relate with activating the Ca2+-APTase, enhancing the uptake and release of Ca2+ from SR (P < 0.05), decreasing the phosphorylation levels of ERK1/2 of myocytes (P < 0.01) and lightening the ultrastructural lesion of cardiac muscle cells. In CaO rats, the Ca2+-ATPase activity decreased clearly com-pared to control (64.99 7.16 vs 94.48 7.68 nmol·min-1 ·mg-1 protein, P < 0.01), while EDDF (100 mg/mL) could significantly increase the activity (87.93 ?9.54 vs 64.99 ?7.16, P < 0.05, n = 7). Both uptake and release rate of Ca2+ (祄ol 45Ca2+/g protein/min) from myocardial SR of CaO rats re-markably decreased compared to control (32.40 ?2.70 and 15.46 ?1.49 vs 61.09 ?10.89 and 25.47 ?4.29, P < 0.05); EDDF (100 mg/mL) could significantly stimulate their activi-ties (50.48 6.76 and 21.76 2.75 vs 32.40 2.70 and 15.46 1.49, P < 0.05). EDDF could evidently down-regulate the phosphorylation of ERK1/2 in myocardial tissue from SHR and CaO rats (P < 0.01), lighten the ultrastructural lesion of cardiac muscle cells of SHR as well. It is concluded that EDDF seems to play protective roles on both structure and function of heart, which closely related with amelioration of Ca2+ transport and inhibition of Ca2+-MAP kinase pathway. 相似文献