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The Applicability of Fluid Model to Electrical Breakdown and Glow Discharge Modeling in Argon

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Chinese Physics Letters 2015年第2期32卷 81-85页

作者： M. N. Stankov M. D. Petkovic v. lj. markovic S. N. Stamenkovic A. P. Jovanovic Department of Physics Faculty of Sciences and Mathematics University of Nis Visegradska 33 Nis18001 Serbia Department of Computer Science Faculty of Sciences and Mathematics University of Nis Visegradska 33 Nig 18001 Serbia

The simple fluid model, an extended fluid model, and the fluid model with nonlocal ionization are applied for the calculations of static breakdown voltages, Paschen curves and current-voltage characteristics. The best agreement with the experimental data for the Paschen curve modeling is achieved by using the model with variable secondary electron yield. The modeling of current-voltage characteristics is performed for different inter-electrode distances and the results are compared with the experimental data. The fluid model with nonlocal ionization shows an excellent agreement for all inter-electrode distances, while the extended fluid model with variable electron transport coefficients agrees well with measurements at short inter-electrode distances when ionization by fast electrons can be neglected.

关键词： Ionization

Efficiency Analysis of Grid-connected Photovoltaic Power Plants

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CSEE Journal of Power and Energy Systems 2017年第3期3卷 269-277页

作者： Milan lj.markovic Rade M.Ciric EPS Elektrodistribucija Srbije Sabac BranchPocerska 8615000 SabacSerbia Higher Education Technical School of Professional Studies Skolska 121000 Novi SadSerbia

Analysis of photovoltaic power plant(PvPP)operations is important to both investors and users and to producers of equipment,researchers and designers as *** paper presents the analysis of the year-long operations of the group PvPPs in Serbia connected to the distribution network which was carried out through specific indicators such as electric power generation,power,capacity factors,specific yield,losses,period of cost effectiveness of the investment,*** attention has been paid to the influence of the azimuth and tilt of the photovoltaic modules on the performances of *** obtained through the year-long extensive measurements were compared to expected yields of PvPPs on the basis of the Climate SAF PvGIS *** results of the analysis indicate that available software applications cannot always provide a good enough forecast of expected electric power production since they cannot always assess well enough the effects of the surrounding facilities on operations of a *** addition,it has been found that the correlation between losses of annual achieved specific yield of a PvPP and the azimuth is represented by a polynomial of the second degree,whereas the correlation between losses of the annual achieved specific yield of a PvPP and the tilt is represented by an exponential function.

关键词： Azimuth capacity factor photovoltaic power plants specific yield tilt

Pyridine Nucleotide Cycling and Control of Intracellular Redox State in Relation to Poly （ADP-Ribose） Polymerase Activity and Nuclear Localization of Glutathione during Exponential Growth of Arabidopsis Cells in Culture

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Molecular Plant 2009年第3期2卷 442-456页

作者： Till K. Pellny vittoria Locato Pedro Diaz vivancos Jelena markovic Laura De Gara Federico v. Pallardo Christine H. Foyer Plant Sciences Rothamsted Research Harpenden Hefts AL5 2 JQ UK CIR UniversitA Campus Bio-Medico V. A. Del Portillo 21 00128 Roma Italy School of Agriculture Food and Rural Development Newcastle University Newcastle upon Tyne NE1 7RU UK Depto. de Fisiologia Av. Blasco Ibanez 15 46010 Valencia Spain Dipartimento di Biologia e Patologia vegetale M E. Orabona 4 70125 Bari Italy

Pyridine nucleotides, ascorbate and glutathione are major redox metabolites in plant cells, with specific roles in cellular redox homeostasis and the regulation of the cell cycle. However, the regulation of these metabolite pools during exponential growth and their precise functions in the cell cycle remain to be characterized. The present analysis of the abundance of ascorbate, glutathione, and pyridine nucleotides during exponential growth of Arabidopsis cells in culture provides evidence for the differential regulation of each of these redox pools. Ascorbate was most abundant early in the growth cycle, but glutathione was low at this point. The cellular ascorbate to dehydroascorbate and reduced glutathione （GSH） to glutathione disulphide ratios were high and constant but the pyridine nucleotide pools were largely oxidized over the period of exponential growth and only became more reduced once growth had ceased. The glutathione pool increased in parallel with poly （ADP-ribose） polymerase （PARP） activities and with increases in the abundance of PARP1 and PARP2 mRNAs at a time of high cell cycle activity as indicated by transcriptome information. Marked changes in the intracellular partitioning of GSH between the cytoplasm and nucleus were observed. Extension of the exponential growth phase by dilution or changing the media led to increases in the glutathione and nicotinamide adenine dinucleotide, oxidized form （NAD）-plus-nicotinamide adenine dinucleotide, reduced form （NADH） pools and to higher NAD/NADH ratios but the nicotinamide adenine dinucleotide phosphate, oxidized form （NADP）-plus-nicotinamide adenine dinucleotide phosphate, reduced form （NADPH） pool sizes, and NAPD/NADPH ratios were much less affected. The ascorbate, glutathione, and pyridine nucleotide pools and PARP activity decreased before the exponential growth phase ended. We conclude that there are marked changes in intracellular redox state during the growth cycle but that redox homeostasis is maint

关键词： glutathione ascorbate Redox control cell cycle cell signaling cell redox state.

A sensitive xanthine oxidase electrode with silk net for estimating fish freshness

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Chinese Journal of Chemistry 1996年第5期14卷 404-411页

作者： Peng, TZ Yang, lj Shen, LQ HANGZHOU UNIv DEPT CHEMHANGZHOU 310028ZHEJIANGPEOPLES R CHINA HANGZHOU INST COMMERCE DEPT FOOD SCIHANGZHOU 310035PEOPLES R CHINA

An enzyme biosensor was constructed using a plate platinum electrode and immobilized xanthine oxidase (XOD). Only a very small quantity of enzyme was chemically immobilized on a special silk net. Hydrogen peroxide released during the enzymatic reaction was detected by the electrode at +0.65 v (vs. Ag/AgCl). The electrode was very sensitive to hypoxanthine and its detection limit was 1X10(-7) mol/L. When it was applied to the determination of fish freshness, the results agreed well with those obtained by traditional methods-determination of total volatile basic nitrogen (TvB-N) and microbial count. A range for estimating the freshness of river fish was suggested.

关键词： xanthine oxidase electrode biosensor amperometry fish freshness

Rheological Behavior of Polymer Melts and Concentrated SolutionsPart v: A New Molecular Theory of Non-linear viscoelasticity for Polymeric Suspensions

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Journal of Materials Science & Technology 1999年第2期15卷 169-177页

作者： Song, MS Zhou, W Hu, GX Hu, lj Beijing Univ Chem Technol Inst Polymer Mat Beijing 100029 Peoples R China Harbin Inst Technol Dept Appl Chem Harbin 150001 Peoples R China

A double-network model is established, which consists of the segments, E and A-constituent chains, the polymeric chains entangled with other ones by multi-entanglement and polymeric chains connected to a great number of destructible particles by multi-adsorption, based on which the E and A-constituent chains can be recreated and released dynamically. The distribution function of the end-to-end vector, the statistical distribution function of conformation for two kinds of chains in the multi-entanglement and multi-adsorption states and their number of polymeric chains are calculated by the combination of statistical mechanics and kinetics. Then the viscoelastic free energies of deformation for two kinds of the networks and suspensions are calculated by Boltzmann's statistical theory. Also, elastic modulus and memory function for two kinds of the network and suspensions are derived. Consequently, a new molecular theory df the non-linear viscoelasticity for polymeric suspensions is proposed, and the constitutive equation and material function with yielding and thinning for the polymeric suspensions in different flow fields are derived from this theory.

关键词： Polymers

Pressure Oxidative Leaching of Complex Sulphide Concentrate

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Journal of Chemistry and Chemical Engineering 2011年第9期5卷 828-831页

作者： vladislav lj. Matkovie Miroslav D. Sokic Branislav R. markovic Institute for Technology of Nuclear and Other Mineral Raw Material 86 Franehet dEsperey Street Belgrade 11000 Serbia

The presented results are related to the leaching of Pb-Zn-Cu-Fe sulphide concentrate, obtained from barite-sulphide ores, under the elevated temperatures and pressures in an autoclave. The leaching process was performed using the sulphur acid solution with the oxygen addition for the separation of the targeted metals from the polymetallic concentrate. In this process influences of various parameters were discussed and then correlated to the leached metals, zinc, copper and iron. Zinc, copper and iron were dissolved in a solution, while lead remained as insoluble in the leach residue. The best leaching results were determined under the temperature of 210 ℃ during the 240 min. Obtained leaching degrees were 98% zinc, 95% copper and 96% iron.

关键词： Complex concentrate presure leaching sulphuric acid oxygen.

Long-term forecasting of annual peak load considering effects of demand-side programs

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Journal of Modern Power Systems and Clean Energy 2018年第1期6卷 145-157页

作者： Nikola lj.RAJAKOvIC vladimir M.SHIljKUT Faculty of Electrical Engineering University of Belgrade Public Enterprise Electric Power Industry of Serbia

The main purpose of this research paper is to investigate the long-term effects of the proposed demandside program,and its impact on annual peak load forecasting important for strategic network *** program comprises a particular set of demand-side measures aimed at reducing the annual peak *** paper also presents the program simulations for the case study of the Electricity Distribution Company of Belgrade(EDB).According to the methodology used,the first step is to determine the available controllable load of the distribution utility/area under *** controllable load is presumed constant over the analyzed time horizon,and the smart grid(SG)infrastructure *** saturation of positive effects during intense program application is also taken into *** and economic input data are taken from the real *** conducted calculations indicate that demand-side programs can bring about the same results as the energy storage in the grids with a strong impact of distributed generation from variable renewable sources(v-RES).In conclusion,the proposed demand-side program is a good alternative to building new power facilities,which can postpone investment costs for a considerable period of time.

关键词： Demand response Demand-side management Forecast Peak load Renewable energy source

Drain amylase value as an early predictor of pancreatic fistula after cephalic duodenopancreatectomy

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World Journal of Gastroenterology 2014年第26期20卷 8691-8699页

作者： vladimir D Dugalic Djordje M Knezevic vladan N Obradovic Miroslava G Gojnic-Dugalic Slavko v Matic Aleksandra R Pavlovic-markovic Predrag D Dugalic Srbislav M Knezevic Department of Hepatobiliary and Pancreatic Surgery First Surgical University HospitalClinical Center of SerbiaSchool of MedicineUniversity of Belgrade St. Joseph’s Hospital Health Center Clinic for Gynecology and Obstetrics Clinical Center of SerbiaSchool of MedicineUniversity of Belgrade Clinic for Gastroenterology and Hepatology Clinical Center of SerbiaSchool of MedicineUniversity of Belgrade Clinic for Gastroenterology and Hepatology University Hospital Zemun

AIM: To determine predictors of clinically relevant pancreatic fistulas (CRPF) by measuring drain fluid amylase (DFA) in the early postoperative period.

关键词： Cephalic duodenopancreatectomy Periampullary tumors Pancreatic fistula Drain fluid amylase level Prediction

Mechanism of Chalcopyrite Leaching in Oxidative Sulphuric Acid Solution

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Journal of Chemistry and Chemical Engineering 2011年第1期5卷 37-41页

作者： Miroslav D. Sokic Branislav R. markovic vladislav lj. Matkovic Nada D. Strbac Dragana T. Zivkovic Institute for Technology of Nuclear and Other Mineral Raw Materials 86 Franchet d ＇Esperey Street Belgrade 11000 Serbia Technical Faculty at Bor University of Belgrade Bor 19210 Serbia

The mechanism of the leaching process of chalcopyrite concentrate with sodium nitrate in sulphuric acid solution were studied and discussed. Chemical reactions of leaching and their thermodynamic probabilities are predicted based on the calculated Gibbs energies and analysis of E-pH diagrams. Experimental data, thermodynamic analysis, chemical, XRD, and SEM/EDX analyses of concentrate and the leach residues, were performed to develop a better understanding of the chemical reactions that took place in the system. Elemental sulphur was formed as the main leaching product, precipitated at the particle surfaces and tended to inhibit the leaching rate.

关键词： Chalcopyrite leaching mechanism sulpruric acid sodium nitrate.