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Performance analysis of adaptive turbo coded modulation with time delay

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Journal of Systems Engineering and Electronics 2004年第1期15卷 73-77页

作者：伍守豪宋文涛罗汉文 ZhongxingTelecommunicationEquipmentCo. Ltd.Shenzhen518057P.R.China DepartmentofElectronicEngineering ShanghaiJiaotongUniversityShanghai200030P.R.China

The method of data fitting is applied to obtain the BER expression for turbo coded modulation, and a fitting mathematical model is proposed, which resolves the problem that there is no exact BER expression for turbo coded modulation in performance analysis. With the time delay consideration, the performance of BER of adaptive turbo coded modulation is analyzed and simulated. The results show that adaptive turbo coded modulation is very sensitive to time delay. In order to meet the target BER requirement, the total time delay should be less than 0 001/f D.

关键词： turbo coded modulation bit error rate time delay

Removal of disinfection by-products formation potential by biologically intensified process

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Journal of Environmental Sciences 2005年第2期17卷 315-318页

作者： ANDong LIWei-guang CUIFu-yi HEXin ZHANGJin-song SchoolofMunicipalandEnvironmentalEngineering HarbinInstituteofTechnologyHarbin150090China ShenzhenWaterGroup Shenzhen518031China

The removal of disinfection by-products formation potential(DBPFP) in artificially intensified biological activated carbon(IBAC) process which is developed on the basis of traditional ozone granular activated carbon was evaluated. By IBAC removals of 31% and 68% for THMFP and HAAFP were obtained respectively. Under identical conditions, the removals of the same substances were 4% and 32% respectively only by the granular activated carbon(GAC) process. Compared with GAC, the high removal rates of the two formed potential substances were due to the increasing of bioactivity of the media and the synergistic capabilities of biological degradation cooperating with activated carbon adsorption of organic compounds. A clear linear correlation(R 2=0.9562 and R 2=0.9007) between DOC HAAFP removal rate and Empty Bed Contact Time(EBCT) of IBAC process was observed, while that between THMFP removal rate and EBCT of GAC was R 2=0.9782. In addition certain linear correlations between THMFP, HAAFP and UV 254 (R 2=0.855 and R 2=0.7702) were found for the treated water. For IBAC process there are also more advantages such as long backwashing cycle time, low backwashing intensity and prolonging activated carbon lifetime and so on.

关键词： intensified biological activated carbon(IBAC) disinfection by-products formation potential(DBPFP) empty bed contact time water treatment

Ammonium removal by modified zeolite from municipal wastewater

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Journal of Environmental Sciences 2004年第6期16卷 1001-1004页

作者： ZHAOYa-ping GAOTing-yao JIANGShang-ying CAODa-wen TheCollegeofEnvironmentalScienceandEngineering TongjiUniversityShanghai200092China TheNationalEngineeringCenterofUrbanPollutionandControl TongjiUniversityShanghai200092China

Ammonium removal by modified zeolite, H-form and Na-form zeolite, were examined by batch-type methods. The adsorption of ammonium on modified zeolite was exothermic process. The saturation adsorption capacity of ammonium on H-form and Na-form zeolite were 21.23 and 41.15 mg/g, respectively. After ten times adsorption-desorption-readsorption cycles the standard deviations of H-form and Na-form zeolite were 6.34% and 6.59%. The zeolite adsorption process has proved cost effective and practical in reducing ammonium by H-form and Na-form zeolite in municipal wastewater from concentration 27.68 mg/L to 2.80 mg/L and 5.91 mg/L.

关键词： ammonium modified zeolite regeneration municipal wastewater

Establishing an animal model of unstable atherosclerotic plaques

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Chinese Medical Journal 2004年第9期117卷 1293-1298页

作者：陈文强张运张梅季晓平殷乐朱永锋 Department of Cardiology Qilu HospitalShandong UniversityJi’nan 250012 China

Background Atherosclerotic plaque rupture and coronary thrombosis are the main causes of acute coronary syndromes. However, there is no animal model of unstable atherosclerotic plaques. The presence of the p53 gene in advanced atherosclerotic plaques and the sensitivity to p53-induced apoptosis of smooth muscle cells isolated from these plaques prompted us to build an animal model of unstable atherosclerotic plaques using p53 gene transfer. Methods Sixty-four New Zealand white rabbits were randomly divided into two groups: group A (n=54) and group B (n=10). Rabbits in group A underwent balloon-induced abdominal aortic wall injury and were then given a diet of 1% cholesterol, while rabbits in group B were given a diet of 1% cholesterol without the induction of aortic wall injury. At the end of the eighth week, rabbits in group A were randomly divided into two subgroups: group A 1 (n=27) and group A 2 (n=27). Recombinant adenovirus carrying p53 or β-galactosidase (LacZ) genes were injected through a catheter into the aortic segments rich in plaques in groups A 1 and A 2, respectively. Two weeks later, 10 rabbits each from groups A 1 and A 2 were killed to observe the occurrence of spontaneous plaque ruptures, and the remaining rabbits in groups A 1, A 2, and B all underwent pharmacological triggering with an injection of Chinese Russell’s viper venom (CRVV) and histamine. Results The over expression of p53 in group A 1 [(32.4±10.2)% vs (15.8±3.6)% in group A 2 and (16.2±6.7)% in group B, P2.5±0.8)% vs (1.0±0.3)% in group A 2 and (0.9±0.4)% in group B, P12 rabbits with a total of 20 lesions aft

关键词： arteriosclerosis · plaque assay · transfection · models animal

Isolation and characterization of heterotrophic nitrifying bacteria in MBR

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Journal of Environmental Sciences 2005年第4期17卷 589-592页

作者： LINYan HEYi-liang KONGHai-nan LIUBin-bin LIYan INAMONYuhei SchoolofEnvironmentalScienceandEngineering ShanghaiJiaotongUniversityShanghai200240China. DepartmentofBiotechnology ShanghaiJiaotongUniversityShanghai200240China NationalInstituteforEnvironmentalStudies16-20nogawa.Tsukuba IbarakiJapan）

The study presented the method for isolating the heterotrophic nitrifiers and the characterization of heterotrophic nitrification. Continuous tests via a membrane bioreactor (MBR) were operated under the controlled conditions to proliferate the nitrifiers. Heterotrophic nitrifying bacteria were isolated from the system in which the efficiency of total nitrogen(TN) removal was up to 80%. Since no autotrophic ammonium and nitrite oxidizers could be detected by fluorescence in situ hybridization(FISH), oxidized-N production was unlikely to be catalyzed by autotrophic nitrifiers during the heterotrophic nitrifiers' isolation in this study. The batch test results indicate that the isolated heterotrophic bacteria were able to nitrify. After 3 weeks incubation, the efficiencies of the COD removal by the three isolated bacterial strains B1, B2, and B3 were 52 6%, 71 7%, and 77 7%, respectively. The efficiencies of the TN removal by B1, B2, and B3 were 35 6%, 61 2% and 68 7%, respectively.

关键词： membrane bioreactor(MBR) simultaneous nitrification and denitrification(SND) heterotrophic nitrification aerobic denitrification

Endocrine disrupting effects on Chinese rare minnow(Gobiocypris rarus) fed with field collected Limnodrilus sp.

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Journal of Environmental Sciences 2004年第5期16卷 784-787页

作者： MATao-wu WANGZi-jian LIUJian-kang StateKeyLaboratoryofEnvironmentalAquaticChemistry ResearchCenterforEco-EnvironmentalSciencesChineseAcademyofSciencesBeijing100085China InstituteofHydrobiology ChineseAcademyofSciencesWuhan430072China

The potential endocrine disrupting effects and other toxicity effects on aquatic biota resulted from food uptake was simulated by feeding the laboratory cultured rare minnow(Gobiocypris rarus) with field collected Limnodrilus sp. The results indicated that the food chain processes affected significantly the growth, slightly reduced gonadosomatic indices, and elevated hepatosomatic indices. There was an obvious vitellogenin(VTG) induction, which generally only occurred in mature female, in the serum of juvenile rare minnow and mature male when fed with Limnodrilus sp. In addition, the rare minnow feeding on Limnodrilus sp. had significantly high renal indices, it meant obvious renal hyperplasia. The present work suggested that Limnodrilus sp. from field water may contain toxic pollutants and could lead to endocrine disruption effects to the predators. It was concluded that endocrine disruptors may not only be assimilated through water, but also be bioconcentrated through food web. The results also suggested the importance of food selection in conducting the study of endocrine disruption effects using sensitive species.

关键词： rare minnow(Grobiocypris rarus) Limnodrilus sp. endocrine disruption food chain vitellogenin

Preparation and characterization of LiMn_(1.5)Me_(0.5)O_4 (Me=Ti,Fe,Ni,Zn) for lithium-ion battery cathode materials

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中国有色金属学会会刊：英文版 2004年第4期14卷 811-816页

作者：赵铭姝宋晓平 School of Science Xi'an Jiaotong University

Based on synthesizing pure spinel type lithium manganese oxides,the derivations such as LiMn1.5Ti0.5-O4,LiMn1.5Fe0.5O4,LiMn1 .5Ni0.5O4 and LiMn1.5Zn0.5O4 were prepared using solid- step-sintering method. The structures were characterized by using XRD,SEM and laser granulometer. The electrochemical measurement results show that the elemen t of iron or nickel can raise the discharging plateau voltage of LiMn2O4,an d element titanium improves the electrochemistry property of LiMn2O4 little,while element zinc destroys the electrochemistry property of LiMn2O4. The i nfluence of elements of titanium,iron,nickel,or zinc on the structure of LiMn 2O4 pure phase was discussed from the viewpoint of structural chemistry.

关键词：锂离子电池电极材料制备 XRD SEM LiMn204

CRITICAL DAMPING OF THE SECOND-ORDERPENDULUM-LIKE SYSTEMS

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Applied Mathematics and Mechanics(English Edition) 2005年第1期26卷 7-16页

作者：李鑫滨黄永念杨莹黄琳 Department of Mechanics and Engineering Science Peking University Institute of Electrical Engineering Yanshan UniversityQinhuangdao 066004 P.R.China

First,the properties of solutions of a typical second-order pendulum-like system with a specified nonlinear function were *** the case with a general form of nonlinearity is considered and its global properties were studied by using the qualitative theory of differential *** a result,sufficient conditions for estimating the critical damp are established,which improves the work by Leonov et al.

关键词： pendulum-like system Lagrange stability gradient-like behavior limit cycles of the second kind

Risk forecasting and evaluating model of Environmental pollution accident

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Journal of Environmental Sciences 2005年第2期17卷 263-267页

作者： ZENGWei-hua CHENGSheng-tong SchoolofEnvironment StateKeyLaboratoryofEnvironmentalSimulationandPollutionControlBeijingNormalUniversityBeijing100875China DepartmentofEnvironmentalScienceandEngineering TsinghuaUniversityBeijing100084China

Environmental risk(ER) factors come from ER source and they are controlled by the primary control mechanism(PCM) of environmental risk, due to the self failures or the effects of external environment risk trigger mechanism, the PCM could not work regularly any more, then, the ER factors will release environmental space, and an ER field is formed up. The forming of ER field does not mean that any environmental pollution accident(EPA) will break out; only the ER receptors are exposed in the ER field and damaged seriously, the potential ER really turns into an actual EPA. Researching on the general laws of evolving from environmental risk to EPA, this paper bring forwards a relevant concept model of risk forecasting and evaluating of EPA. This model provides some scientific methods for risk evaluation, prevention and emergency response of EPA. This model not only enriches and develops the theory system of environment safety and emergency response, but also acts as an instruction for public safety, enterprise's safety management and emergency response of the accident.

关键词： environmental risk(ER) environmental pollution accident(EPA) ER evaluation ER field EPA damage field