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Square wave volt-coulometry

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Chinese Science Bulletin 1997年第5期42卷 390-396页

作者： Mo, JY Zhang, J Mo, sy Department of Chemistry Zhongshan Univenity Guangzhou China Department of Chemistry Hong Kong University Hong Kong

FOR a long time, people pay particular attention to the way to decrease the charging current and improve the Faraday current in the modern square wave voltammetry (SWV), but the effects of random noise on analytical result are ignored. However, it is impossible to avoid the random noise absolutely in the measuring process. especially, when the concentration is low, the signal is affected seriously by the random noise and it is difficult to get a lower detection limit. So it is necessary to know how to decrease the random noise in order to get a lower detection limit, while trying to find out how to decrease the charging current. A new sampling technique using the square wave potential scan is proposed to smooth the random noise and decrease the detection limit in SWV. The foundation of this new method comes from one of the laws of mathematical statistics; that is, the positive and negative probable errors in a group of detected data exist equally and then the sum of all the errors is ze-

关键词： square wave voltammetry square wave volt-coulometry simple reverse system catalytic system.

Multi scale risk measurement in electricity market:a wavelet based value at risk approach

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Journal of Southeast University(english edition) 2008年第S1期24卷 54-59页

作者： Guu sy-Ming Lai Kin Keung College of Management Yuan Ze University School of Business Administration Hunan University

Value at risk (VaR) is adopted to measure the risk level in the electricity market. To estimate VaR at higher accuracy and reliability, the wavelet variance decomposed approach for value at risk estimates (WVDVaR) is proposed. empirical studies conduct in five Australian electricity markets, which evaluate the performances of both the proposed approach and the traditional ARMA-GARCH approach using the Kupiec backtesting procedure. experimental results suggest that the proposed approach measures electricity market risks at higher accuracy and reliability than the bench mark ARMA-GARCH approach, as indicated by the higher p values during the Kupiec backtesting procedure. In addition, the new approach also provides more insight into the risk evolution process over time and helps in adjusting VaR estimates to the time horizons that best suit investor interests. The distribution of risk according to investor preferences is shown by decomposing VaR across different time horizons. This also provides important information for the appropriate aggregation of risk measures based on investor investment preferences.

关键词： wavelet analysis value at risk risk management Australian electricity market

Solvent effects on competitive intramolecular electron transfer and energy transfer in a covalently linked porphyrin-phthalocyanine heterodimer

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Chinese Journal of Chemistry 1996年第5期14卷 412-420页

作者： Tian, HJ Zhou, QF Shen, sy Xu, HJ ACAD SINICA INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA

Photophysical properties of a porphyrin-phthalocyanine heterodimer covalently linked with a dipentoxy chain have been studied. Absorption spectra show that there is weak exciton coupling between the two chromophores in the ground state. Fluorescence spectra show that intramolecular energy transfer from porphyrin to phthalocyanine moiety occurs in competition with electron transfer. The efficiency of these two processes depends upon the mutual orientation of the two chromophores. The effect of solvent, polarity on the intramolecular processes is also discussed.

关键词： solvent effects electron transfer energy transfer porphyrin phthalocyanine

A FINITe-eLeMeNT ANALYSIS OF eLeCTROMAGNeTIC SHeeT MeTAL-eXPANSION PROCeSS

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中国有色金属学会会刊：英文版 1998年第3期8卷 135-140页

作者： Huang, sy Chang, ZH Wang, ZR Wang, LF Yang, M Wuhan Automot Polytech Univ Sch Mat Engn Wuhan 430070 Peoples R China Harbin Inst Technol Sch Mat Sci & Engn Harbin 150006 Peoples R China

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关键词： finite element analysis electromagnetic forming magnetic pressure

A review of the formulation and application of the spatial equilibrium models to analyze policy

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Journal of Forestry Research 2011年第4期22卷 671-679页

作者： Phan sy Hieu Steve Harrison The Centre for Informatics and Statistics Ministry of Agriculture and Rural Development in Vietnam No. 2 Ngoc Ha Street Ba Dinh district Hanoi Vietnam Associate Professor the School of Economics the University of Queensland Australia.

This paper reviews alternative market equilibrium models for policy analysis. The origin of spatial equilibrium models and their application to wood and wood-processing industries are described. Three mathematical programming models commonly applied to solve spatial problems - namely linear programming, non-linear programming and mixed complementary programming - are reviewed in terms of forms of objective functions and constraint equalities and inequalities. These programming are illustrated with numerical examples. Linear programming is only applied in transportation problems to solve quantities trans, ported between regions when quantities supplied and demanded in each region are already known. It is argued that linear programming can be applied in broader context to transportation problems where supply and demand quantities are unknown and are linear. In this context, linear programming is seen as a more convenient method for modelers because it has a simpler objective function and does not require as strict conditions, for instance the equal numbers of variables and equations required in mixed complementary programming. Finally, some critical insights are provided on the interpretation of optimal solutions generated by solving spatial equilibrium models.

关键词： simplex method reduced-gradient linear programming non-linear programming mixed complementary programming

SCHISTOSOMIASIS VACCINATION HISTORICAL DeVeLOPMeNT,PReSeNT STATUS AND FUTURe PROSPeCTS

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Chinese Medical Journal 1980年第5期93卷 297-312页

作者： HF Hsü sy Li Hsü LK eveland Professor emeritus Department of Preventive Medicine and Environmental HealthCollege of MedicineUniversity of IowaIowa CityIowaUSA. Professor Department of Preventive Medicine and Environmental HealthCollege of MedicineUniversity of IowaIowa CityIowaUSA. Associate Professor Department of Microbiology and ImmunologyState University of New YorkBrooklynNew YorkUSA.

50 years of research on killed or live vaccinefor schistosomiasis without successful produc-tion of a human schistosomiasis vaccine arereviewed.

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effect of extracts from Stachys sieboldii Miq. on cellular reactive oxygen species and glutathione production and genomic DNA oxidation

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Asian Pacific Journal of Tropical Biomedicine 2018年第10期8卷 485-489页

作者： JW Lee W Wu sy Lim Division of Marine Bioscience Korea Maritime and Ocean University Department of Marine Bio-Pharmacology Shanghai Ocean University

Objective: To evaluate the antioxidant activity of extracts and fractions from Stachys sieboldii Miq., and to examine its effect on the cellular reactive oxygen species(ROS) and glutathione(GSH) production and genomic DNA oxidation in HT-1080 cells. Methods: The ROS generation induced by H2 O2 was measured by the dichlorofluorescein-diacetate assay. GSH levels were measured using a fluorescent method with mBBr. Genomic DNA oxidative damage was measured with levels of oxidative DNA induced by the reaction of ferritin with H2 O2. Results: The n-hexane, 85% aqueous methanol and n-butanol fractions(0.05 mg/mL concentrations) inhibited H2 O2-induced ROS generation by 63%, 35% and 45%, respectively. GSH levels were significantly increased in both acetone+methylene chloride and methanol extracts(Pementation of cells with n-hexane significantly increased GSH levels at concentrations of 0.05 mg/mL(Pe acetone+methylene chloride and methanol extracts, as well as all fractions significantly inhibited oxidative DNA damage(Pese results indicate that cellular oxidation was inhibited by the n-hexane fraction and this fraction may contain valuable active compounds.

关键词： Stachys sieboldii Miq. Reactive oxygen species Glutathione DNA oxidation Antioxidant

State of the Art of Artificial Intelligence Applications in Oncology

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Open Journal of Applied Sciences 2023年第12期13卷 2245-2262页

作者： Idrissa sy Mamadou Bousso Ayoub Insa Correa Madieng Dieng Faculty of Science and Technology Iba Der THIAM University of Thies Thies Senegal Faculty of Medicine Cheikh Anta DIOP University of Dakar Dakar Senegal

Artificial intelligence (AI) operates by using algorithms and statistical models based on data, enabling computers to imitate a real form of intelligence. The structure of the data available and the aim of the research define the technique to be adopted, which will be evaluated by its degree of accuracy and its capacity for generalization. In recent years, several applications of artificial intelligence have emerged in the fight against cancer, due to its development, computing power and learning potential. This article presents the current state of AI systems, describing the techniques and innovations that have led to satisfactory results in the fight against cancer. .

关键词： Artificial Intelligence Cancer Prognosis

Specific Mass Spectrometric Fragmentations from the Dissociation of Intermediate Ion-Neutral Complexes

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Chinese Chemical Letters 1998年第1期9卷 93-97页

作者： She, YM Wei, JH Tu, YP Liu, sy Hunan Normal Univ Anal & Testing Ctr Changsha 410006 Hunan Peoples R China Chinese Acad Sci Changchun Inst Appl Chem Changchun 1300222 Jilin Peoples R China

It is reported that two kinds of specific mass spectrometric fragmentations are generated from dissociations of the intermediates of both the ion-neutral complex and the proton-bound complex. Collision-induced dissociation, isotopic labelling, and semi-empirical AM1 calculations were used to investigate the formation mechanism of the ion of m/z 139 from ionized tetrahydroimidazole-substituted methylene beta-diketones and the unimolecular fragmentations pathway of 3-phenyl-1-butyn-3-ol upon electron impact.

关键词： mass spectrometric fragmentation ion-neutral complex proton bound complex dissociation