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Geographical Differences and Influencing Factors of Rural Energy Consumption in Southwest Mountain Areas in China:A Case Study of Zhaotong City 被引量:5
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作者 SUN Wei HAN Xiaoxu +1 位作者 SHENG Kerong FAN Jie 《Journal of Mountain Science》 SCIE CSCD 2012年第6期842-852,共11页
China is a mountainous country,and Southwest mountain areas cover the most mountain areas in China and have the most serious problems.Taking Zhaotong city as the study area,based on 902 rural household questionnaires ... China is a mountainous country,and Southwest mountain areas cover the most mountain areas in China and have the most serious problems.Taking Zhaotong city as the study area,based on 902 rural household questionnaires of 11 villages in 2 counties and Tobit model,this paper analyzes the geographical differences and influencing factors of energy consumption for non-production purposes of rural households living in different terrain conditions.This research finds that:(1) Coal takes up the main part of energy consumption in valley areas and coal consumption is mainly affected by per capita cultivated land area,household income,proportion of rural household energy expenditure in total expenditure,coal price,and family population size.Firewood takes up the main part of energy consumption in high mountain areas and firewood consumption is mainly affected by per capita firewood forest area,distance to purchase coal,household income,electricity price,and coal price.(2) Only when the distance is greater than 20 kilometers,that is the average distance of rural households living in middle mountain areas(1,600m^1,800m) to purchase coal,the transportation condition has a significant impact on coal consumption.(3) In high mountain areas,prices of coal and electricity are the main factors influencing energy consumption choice of rural households.Too high prices of coal and electricity would to some extent lead rural households to choose firewood as the main energy consumption type.Compared to coal,rural households prefer to choose electricity. 展开更多
关键词 Southwest mountain areas Sustainable livelihoods Energy for non-production purposes TERRAIN
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Kinetic and binding equilibrium studies of dihydroflavonol 4-reductase from Vitis vinifera and its unusually strong substrate inhibition 被引量:5
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作者 Nadia Trabelsi Béatrice Langlois d'Estaintot +2 位作者 Gilles Sigaud Bernard Gallois Jean Chaudière 《Journal of Biophysical Chemistry》 2011年第3期332-344,共13页
Dihydroflavonol 4-reductase (DFR), a member of the short-chain dehydrogenase family, catalyzes the last common step in the biosynthesis of flavan-3-ols and condensed tannins. Initial rates of DFR were measured by moni... Dihydroflavonol 4-reductase (DFR), a member of the short-chain dehydrogenase family, catalyzes the last common step in the biosynthesis of flavan-3-ols and condensed tannins. Initial rates of DFR were measured by monitoring the 340-nm absorbance decrease resulting from the joint consumption of dihydroquercetin (DHQ) and NADPH, as a function of pH, temperature and ionic strength. At pH 6.5 and 30o C, substrate inhibition was observed above 30 μM DHQ. At lower/non-inhibitory DHQ concentrations, NADP+ behaves as a competitive inhibitor with respect to NADPH and as a mixed inhibitor with respect to DHQ, which supports a sequential ordered mechanism, with NADPH binding first and NADP+ released last. Binding-equilib-rium data obtained by means of the chromatographic method of Hummel and Dreyer at pH 7.5 and by isothermal calorimetric titration at pH 6.5 led to the conclusion that ligands of the apoenzyme included NADPH, NADP+ and DHQ. The mechanism which best accounts for substrate inhibition at pH 6.5 in the absence of product involves the formation of a binary non-productive E.DHQ complex. Thus, a productive ternary complex cannot be formed when DHQ binds first. This mechanism of inhibition may prevent the accumulation of unstable leucoanthocyanidins within cells. 展开更多
关键词 SUBSTRATE Inhibition Steady-State Kinetics HUMMEL and Dreyer Technique Isothermal TITRATION Calorimetry non-productive Enzyme SUBSTRATE Complex
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Analysis of Waste-Rock Transportation Process Performance in an Open-Pit Mine Based on Statistical Analysis of Cycle Times Data 被引量:1
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作者 Samwel Victor Manyele 《Engineering(科研)》 2017年第7期649-679,共31页
In this paper, the performance of a waste rock transportation process in an open pit mine was assessed by using cycle time data. A computerized truck-excavator dispatch system was used to record the cycle times. The p... In this paper, the performance of a waste rock transportation process in an open pit mine was assessed by using cycle time data. A computerized truck-excavator dispatch system was used to record the cycle times. The process was broken into seven steps (or components of the total cycle), durations of which were recorded for a period of 1 month, leading to N = 60,690 data points or dispatches. The open pit mine studied consisted of 12 waste types loaded by 14 excavators and hauled by 49 trucks (at a trucks-to-excavator ratio of 3.5:1) in 75 changing locations. The string-type data was coded using integers to allow a FORTRAN code to extract process performance parameters using statistical analysis. The study established a wide range of parameters including: the waste material generation rate (about 1.73 million t/month, 81% comprising waste rock), truck fill factor, f, total cycle time (Tct), production capacity, theoretical cycle time, non-productive cycle time Tnp, and cycle time performance ratio (CTPR), denoted as Tpr. The factors affecting the process performance include: truck model, excavator model, location (haul distance and road conditions) and material type. For a fixed material type and tonnage, the PDFs of the cycle time components were logarithmic in nature, capable of differentiating performance variations under different factors. It was concluded that the performance of the waste material transportation system in this mine was determined to be acceptable due to mean value of Tpr = 2.432 being closer to unity. Reduction measures were suggested to minimize the cycle time for the process bottlenecks determined from Pareto analysis (that is, full haul, empty haul and loading processes). 展开更多
关键词 Potentially Acid-Forming (PAF) ROCK Non-Acid FORMING (NAF) ROCK TRUCK Utilization TRUCK Fill-Factor QUEUING TIME Loading CYCLE TIME Full and Empty Haul Total CYCLE TIME Theoretical CYCLE TIME non-productive CYCLE TIME CYCLE TIME Performance Ratio
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Investigation of Excavator Performance Factors in an Open-Pit Mine Using Loading Cycle Time
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作者 Samwel Victor Manyele 《Engineering(科研)》 2017年第7期599-624,共26页
This study presents the effect of excavator model, loading operation location, shift availability and truck-shovel combination on loading cycle time and productivity of an open-pit mine. The loading cycle time was use... This study presents the effect of excavator model, loading operation location, shift availability and truck-shovel combination on loading cycle time and productivity of an open-pit mine. The loading cycle time was used to assess the material loading system performance which is one of the key components of the total cycle time for material transportation in an open-pit mine. Loading is among the components of cycle time during which material is being handled. The data analyzed?was?collected from a computerized dispatch system at GGM from which 62,000 loading dispatches per month involving several shifts, 14 excavators and 49 trucks were loaded. About 4465 dispatches per excavator and 1276 dispatches per truck were assessed using loading cycle time data for each dispatch for a period of four months (between August and December). Under fixed tonnage loaded and waste type (33 t of non-acid forming waste rock),?it was observed that loading cycle time depends on excavator model, location and truck being loaded. Average cycle times, PDFS?and CDFS of loading cycle time series were used to identify differences in performance under different situations. It was concluded that shift availability for excavators, loading location, excavator model and truck-shovel combinations strongly affect the productivity during loading process in an open-pit mine. 展开更多
关键词 Potentially Acid-Forming (PAF) ROCK Non-Acid FORMING (NAF) ROCK TRUCK Utilization TRUCK Fill-Factor Queuing TIME LOADING CYCLE TIME Full and Empty Haul Total CYCLE TIME Theoretical CYCLE TIME non-productive CYCLE TIME CYCLE TIME Performance Ratio
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FUBINI THEOREM w.r.t. STOCHASTIC MEASURE ON PRODUCT MEASURABLE SPACE
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作者 陈培德 宁克标 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 1994年第4期337-348,共12页
Using the new results about the existence of product S.M.[1], we get two forms of Fubini theorem about product S.M. on product measurable space in § 1-§ 2. On being restricted to the special case of S.M. (I)... Using the new results about the existence of product S.M.[1], we get two forms of Fubini theorem about product S.M. on product measurable space in § 1-§ 2. On being restricted to the special case of S.M. (I), the conditions needed are much weaker than those of [2] and couldn't be improved anymore. In the rest of this paper, we discuss how to calculate double integration w.r.t .non-product type S.M. on product space by iterated integration. Even in the casc of classical measure theory, the problem hasn't been thoroughly solved yet.Por the first two sections we suppose that (X, X), (Y, y), are measurable spaces,any two of which form a 'nice pair'[1], P is a probability mea.sure on is the P-completion of so is a complete probability space. Let L be the coniplete topological linear space which consists of all a.s. finite r.v. on (we identify those r.v. which differ only on a set of probability 0), If Z,W are valued S.M. on X, y respectively, then there uniquely exists an valued S.M. on X × y, denoted by Z × W, such that Z ×W(E ×F) = Z(E)W(F)for any E ∈ X, F ∈ y[1] . Thus we may discuss the double integrals of the X × y measurable fonction f = j(x,y) w.r.t. Z × W, denoted br (or shortly by , at least for thcoe f either ounded or nonnegative. we call f integrable w.r.t.Z ×W if both f+dZ × W and f-dZ×W ∈ so All integrable f form a complete topological linear space, denoted by (or shortly by L1(dZ × W))[3].In this paper, we discuss how to calculate the double stochastic integrals by iterated stochas tic integrals. Since there are two different ordare to calculate the iterated stochastic integrals,and both are equal to the sanie double stochastic integral, so tbe order of the iterated stochastic Received July 6, 1991. Revised January 29, 1993.This project is supported by the National Natural Sciences Foundation of China.integrals is exchangeable. In classical analysis, such a kind of statement is usually called the Fubini theorem. 展开更多
关键词 Product stochastic measure non-product type S. M enlarged type S. M.
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