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The Customer Requirements Analysis Method of Engineering Products Based on Multiple Preference Information
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作者 Guo Mao 《Proceedings of Business and Economic Studies》 2024年第1期204-209,共6页
To effectively evaluate the fuzziness of the market environment in product planning,a customer requirements analysis method based on multiple preference information is proposed.Firstly,decision-makers use a preferred ... To effectively evaluate the fuzziness of the market environment in product planning,a customer requirements analysis method based on multiple preference information is proposed.Firstly,decision-makers use a preferred information form to evaluate the importance of each customer requirement.Secondly,a transfer function is employed to unify various forms of preference information into a fuzzy complementary judgment matrix.The ranking vector is then calculated using row and normalization methods,and the initial importance of customer requirements is obtained by aggregating the weights of decision members.Finally,the correction coefficients of initial importance and each demand are synthesized,and the importance of customer requirements is determined through normalization.The development example of the PE jaw crusher demonstrates the effectiveness and feasibility of the proposed method. 展开更多
关键词 product planning Customer requirements Importance ratings Multi-format information
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Effective Return Rate Prediction of Blockchain Financial Products Using Machine Learning
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作者 K.Kalyani Velmurugan Subbiah Parvathy +4 位作者 Hikmat A.M.Abdeljaber T.Satyanarayana Murthy Srijana Acharya Gyanendra Prasad Joshi Sung Won Kim 《Computers, Materials & Continua》 SCIE EI 2023年第1期2303-2316,共14页
In recent times,financial globalization has drastically increased in different ways to improve the quality of services with advanced resources.The successful applications of bitcoin Blockchain(BC)techniques enable the... In recent times,financial globalization has drastically increased in different ways to improve the quality of services with advanced resources.The successful applications of bitcoin Blockchain(BC)techniques enable the stockholders to worry about the return and risk of financial products.The stockholders focused on the prediction of return rate and risk rate of financial products.Therefore,an automatic return rate bitcoin prediction model becomes essential for BC financial products.The newly designed machine learning(ML)and deep learning(DL)approaches pave the way for return rate predictive method.This study introduces a novel Jellyfish search optimization based extreme learning machine with autoencoder(JSO-ELMAE)for return rate prediction of BC financial products.The presented JSO-ELMAE model designs a new ELMAE model for predicting the return rate of financial products.Besides,the JSO algorithm is exploited to tune the parameters related to the ELMAE model which in turn boosts the classification results.The application of JSO technique assists in optimal parameter adjustment of the ELMAE model to predict the bitcoin return rates.The experimental validation of the JSO-ELMAE model was executed and the outcomes are inspected in many aspects.The experimental values demonstrated the enhanced performance of the JSO-ELMAE model over recent state of art approaches with minimal RMSE of 0.1562. 展开更多
关键词 Financial products blockchain return rate prediction model machine learning parameter optimization
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Degradation rates and products of fluticasone propionate in alkaline solutions 被引量:1
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作者 Tadakazu Tokumura Naoko Yoshida +2 位作者 Kanami Mori-Yasumoto Osamu Shirota Takuro Kurita 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2017年第5期297-302,共6页
The apparent degradation rate constant of fluticasone propionate(FLT) in 0.1 M NaOH:methanol=1:1 at 37 °C was previously reported to be 0.169 ± 0.003 h^(-1), and four degradation products(products 1–4) were... The apparent degradation rate constant of fluticasone propionate(FLT) in 0.1 M NaOH:methanol=1:1 at 37 °C was previously reported to be 0.169 ± 0.003 h^(-1), and four degradation products(products 1–4) were observed in the solution. The aims of the present study were to assess the degradation rates of FLT in other alkaline solutions and clarify the chemical structures of the four degradation products in order to obtain basic data for designing an enema for inflammatory bowel disease. The apparent degradation rate constants in 0.05 M NaOH and 0.1 M NaOH:CH_3CN=1:1 were 0.472 ± 0.013 h^(-1) and 0.154 ± 0.000 h^(-1)(n=3), respectively. The chemical structures of products 1–4 in 0.1 M NaOH:methanol=1:1 were revealed by nuclear magnetic resonance(NMR)and mass spectrometry data. The chemical structure of products 2 was that the 17-position of the thioester moiety of FLT was substituted by a carboxylic acid. The degradation product in 0.1 M NaOH:CH_3CN=1:1 was found to be product 2 based on ~1H NMR data. The degradation product in 0.05 M NaOH was considered to be product 2 based on the retention time of HPLC. These results are useful for detecting the degradation products of FLT by enzymes of the intestinal bacterial flora in the large intestine after dosing FLT as an enema. 展开更多
关键词 FLUTICASONE PROPIONATE DEGRADATION rate DEGRADATION products Chemical structure ALKALINE solution
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Gas-Water Production of a Continental Tight-Sandstone Gas Reservoir under Different Fracturing Conditions
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作者 Yan Liu Tianli Sun +1 位作者 Bencheng Wang Yan Feng 《Fluid Dynamics & Materials Processing》 EI 2024年第6期1165-1180,共16页
A numerical model of hydraulic fracture propagation is introduced for a representative reservoir(Yuanba continental tight sandstone gas reservoir in Northeast Sichuan).Different parameters are considered,i.e.,the inte... A numerical model of hydraulic fracture propagation is introduced for a representative reservoir(Yuanba continental tight sandstone gas reservoir in Northeast Sichuan).Different parameters are considered,i.e.,the interlayer stress difference,the fracturing discharge rate and the fracturing fluid viscosity.The results show that these factors affect the gas and water production by influencing the fracture size.The interlayer stress difference can effectively control the fracture height.The greater the stress difference,the smaller the dimensionless reconstruction volume of the reservoir,while the flowback rate and gas production are lower.A large displacement fracturing construction increases the fracture-forming efficiency and expands the fracture size.The larger the displacement of fracturing construction,the larger the dimensionless reconstruction volume of the reservoir,and the higher the fracture-forming efficiency of fracturing fluid,the flowback rate,and the gas production.Low viscosity fracturing fluid is suitable for long fractures,while high viscosity fracturing fluid is suitable for wide fractures.With an increase in the fracturing fluid viscosity,the dimensionless reconstruction volume and flowback rate of the reservoir display a non-monotonic behavior,however,their changes are relatively small. 展开更多
关键词 Tight sandstone gas reservoir fracture propagation flowback rate gas production law water production law influencing factor
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Impact of Different Rates of Nitrogen Supplementation on Soil PhysicochemicalProperties and Microbial Diversity in Goji Berry
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作者 Xiaojie Liang Wei An +4 位作者 Yuekun Li Yajun Wang Xiaoya Qin Yanhong Cui Shuchai Su 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期467-486,共20页
Goji berry(Lycium barbarum L.)is substantially dependent on nitrogen fertilizer application,which can signifi-cantly enhance fruit yield and Goji berry industrial development in Ningxia,China.This study aimed to analyz... Goji berry(Lycium barbarum L.)is substantially dependent on nitrogen fertilizer application,which can signifi-cantly enhance fruit yield and Goji berry industrial development in Ningxia,China.This study aimed to analyze the functions of differential nitrogen application rates including low(N1),medium(N2),and high(N3)levels in soil microbial community structure(bacterial and fungal)at 2 diverse soil depths(0-20,20-40 cm)through high-throughput sequencing technology by targeting 16S RNA gene and ITS1&ITS2 regions.All the observed physicochemical parameters exhibited significant improvement(p<0.05)with increased levels of nitrogen and the highest values for most parameters were observed at N2.However,pH decreased(p<0.05)gradually.The alpha and beta diversity analyses for bacterial and fungal communities’metagenome displayed more similarities than differences among all groups.The top bacterial and fungal phyla and genera suggested no obvious(p>0.05)differences among three group treatments(N1,N2,and N3).Furthermore,the functional enrichment analysis demonstrated significant(p<0.05)enrichment of quorum sensing,cysteine and methionine metabolism,and transcriptional machinery for bacterial communities,while various saprotrophic functional roles for fungal communities.Conclusively,moderately reducing the use of N-supplemented fertilizers is conducive to increasing soil nitrogen utilization rate,which can contribute to sustainable agriculture practices through improved soil quality,and microbial community structure and functions. 展开更多
关键词 Goji berry production Ningxia China differential nitrogen supplementation rates 16S RNA gene and IT1&IT2 region sequencing soil physicochemical properties
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Application of Six Sigma DMAIC Method in Improving the Good Rate of Blank Value of Cytological Method for Dairy Products
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作者 Yunxia WANG Shuhuan ZHAO +3 位作者 Lijun LIU Xue HU Cuizhi LI Zhiyong LU 《Asian Agricultural Research》 2021年第10期48-53,共6页
In this paper,the six Aigma DMAIC method was used to systematically analyze and study the process affecting the good rate of blank value of cytological method for dairy products.Through data collection,analysis and ve... In this paper,the six Aigma DMAIC method was used to systematically analyze and study the process affecting the good rate of blank value of cytological method for dairy products.Through data collection,analysis and verification in each link,the room for improvement in the experimental process was identified.C&E matrix and FMEA were used to analyze the factors affecting the good rate of blank value.Through the DOE experiment design method and risk analysis,the main influencing factors were optimized and improved.The optimized experimental conditions were:silica gel activation temperature(500±50)℃,activation time(23±1)h,cells adherent rate(95±1)%,and single-use of 1.5 mL conical flask.Under the above conditions,the good rate of blank value of cytological method was improved from 52.8%to 100%.The improvement of these conditions is of great significance to ensure the accuracy of results,save the testing cost and improve the testing efficiency. 展开更多
关键词 Six Sigma DMAIC Dairy product Good rate
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Tentative tariff rate for partial import and export products adjusted
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《China Rare Earth Information》 2006年第12期3-3,共1页
The tentative tariff rate for partial import and export products was adjusted since November 1^(st) of 2006.Total 58 imported commodities will be imposed lower tentative
关键词 rate Tentative tariff rate for partial import and export products adjusted
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The Influence of the Corrosion Product Layer Generated on the High Strength Low-Alloy Steels Welded by Underwater Wet Welding with Stainless Steel Electrodes in Seawater 被引量:3
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作者 BAI Qiang ZOU Yan +3 位作者 KONG Xiangfeng GAO Yang DONG Sheng ZHANG Wei 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第1期49-56,共8页
The high strength low-alloy steels are welded by underwater wet welding with stainless steel electrodes. The microstructural and electrochemical corrosion study of base metal(BM), weld zone(WZ) and heat affected zone(... The high strength low-alloy steels are welded by underwater wet welding with stainless steel electrodes. The microstructural and electrochemical corrosion study of base metal(BM), weld zone(WZ) and heat affected zone(HAZ) are carried out to understand the influence of the corrosion product layer generated on the high strength low-alloy steels welded by underwater wet welding with stainless steel electrodes, methods used including, potentiodynamic polarization, electrochemical impedance spectroscopy(EIS) and scanning electron microscope(SEM). The results indicate that the WZ acts as a cathode and there is no corrosion product on it throughout the immersion period in seawater. The HAZ and BM acts as anodes. The corrosion rates of the HAZ and BM change with the immersion time increasing. In the initial immersion period, the HAZ has the highest corrosion rate because it has a coarse tempered martensite structure and the BM exhibites a microstructure with very fine grains of ferrite and pearlite. After a period of immersion, the BM has the highest corrosion rate. The reason is that the corrosion product layer on the HAZ is dense and has a better protective property while that on the BM is loose and can not inhibit the diffusion of oxygen. 展开更多
关键词 UNDERWATER WET welding CORROSION rate CORROSION product protective property
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Entropy Production Rate for Avascular Tumor Growth 被引量:1
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作者 Elena Izquierdo-Kulich Esther Alonso-Becerra José M Nieto-Villar 《Journal of Modern Physics》 2011年第6期615-620,共6页
The entropy production rate was determined for avascular tumor growth. The proposed formula relates the fractal dimension of the tumor contour with the quotient between mitosis and apoptosis rate, which can be used to... The entropy production rate was determined for avascular tumor growth. The proposed formula relates the fractal dimension of the tumor contour with the quotient between mitosis and apoptosis rate, which can be used to characterize the degree of proliferation of tumor cells. The entropy production rate was determined for fourteen tumor cell lines as a physical function of cancer robustness. The entropy production rate is a hallmark that allows us the possibility of prognosis of tumor proliferation and invasion capacities, key fac-tors to improve cancer therapy. 展开更多
关键词 ENTROPY production rate CANCER ROBUSTNESS CANCER Evolution
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Theoretical prediction of energy dependence for D+BrO→DBr+O reaction:The rate constant and product rotational polarization 被引量:1
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作者 张莹莹 解廷献 +2 位作者 李泽瑞 石英 金明星 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第3期412-417,共6页
A quasi-classical trajectory(QCT) calculation is used to investigate the vector and scalar properties of the D + Br O → DBr + O reaction based on an ab initio potential energy surface(X1A state) with collision ... A quasi-classical trajectory(QCT) calculation is used to investigate the vector and scalar properties of the D + Br O → DBr + O reaction based on an ab initio potential energy surface(X1A state) with collision energy ranging from 0.1 kcal/mol to 6 kcal/mol. The reaction probability, the cross section, and the rate constant are studied. The probability and the cross section show decreasing behaviors as the collision energy increases. The distribution of the rate constant indicates that the reaction favorably occurs in a relatively low-temperature region(T 〈 100 K). Meanwhile, three product angular distributions P(θr), P(φr), and P(θr, φr) are presented, which reflect the positive effect on the rotational angular momentum j' polarization of the DBr product molecule. In addition, two of the polarization-dependent generalized differential cross sections(PDDCSs), PDDCS00 and PDDCS20, are computed as well. Our results demonstrate that both vector and scalar properties have strong energy dependence. 展开更多
关键词 quasi-classical trajectory cross section rate constant product angular distributions
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The Effect of Toxic Sulfide Exposure on Oxygen Consumption and Oxidation Products in Urechis unicinctus(Echiura:Urechidae) 被引量:11
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作者 WANG Sifeng ZHANG Zhifeng +2 位作者 CUI He KANG Kyoung Ho MA Zhuojun 《Journal of Ocean University of China》 SCIE CAS 2010年第2期157-161,共5页
To investigate sulfide detoxification in Urechis unicinctus,oxygen consumption rate and sulfide detoxification productswere analyzed during sulfide exposure under controlled laboratory conditions.The results showed th... To investigate sulfide detoxification in Urechis unicinctus,oxygen consumption rate and sulfide detoxification productswere analyzed during sulfide exposure under controlled laboratory conditions.The results showed that oxygen consumption rateswere elevated significantly during 3 h sulfide exposure compared to the control(P<0.05).The concentration of sulfite in body walland hindgut of experimental worms increased significantly(P<0.05)when exposed to 50μmolL-1sulfide,reached a maximum at24 h and then decreased.Similar result was observed in worms exposed to 150μmolL-1sulfide except that sulfite concentrationreached a maximum at 12 h.Contents of thiosulfate in body wall and hindgut of U.unicinctus exposed to sulfide were also significantly higher than that of the control without sulfide exposure.In conclusion,during short-time sulfide exposure U.unicinctus mayraise oxygen consumption to detoxify toxic sulfide into sulfite and thiosulfate.Sulfide detoxification was restrained when the expo-sure time was prolonged or sulfide concentration was increased,which was indicated by decrease of sulfite,the intermediate productof sulfide detoxification. 展开更多
关键词 硫化物 效果图 耗氧量 有毒 曝光 产品 动物 单环
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Composite materials for primary aircraft structures:from development phase to high volume production rate 被引量:3
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作者 LI Helen FIORE Lucien JIANG Zhen 《民用飞机设计与研究》 2020年第1期125-128,共4页
From 1980’s decade,the introduction of carbon composite materials in structural applications has been consistently increased in the successive generations of civil aircraft from Single Aisle to Middle-long Range to a... From 1980’s decade,the introduction of carbon composite materials in structural applications has been consistently increased in the successive generations of civil aircraft from Single Aisle to Middle-long Range to achieve a culminant point with more than 50%in structure weight in recent commercial civil aircraft.This evolution,done through successive iterations,has been possible by combining in the same time the improvement of intrinsic composite material performances and its transformation into prepreg production technologies together with the development of new manufacturing process for material lay-up automation at composite shop-floor manufacturer of aircraft composite parts.New challenges are still coming to continuously develop materials and technologies in order to pursue the production more cost-effective composite parts.Associated to higher aircraft production rate for single aisle,new challenges may force material and aircraft designers and producers to furthermore drive new products and processes introduction and new ways of transformation within in next decade of composite aircraft designs.We propose to illustrate these trends using past and recent developments and our return of experience from Hexcel on Civil Aircraft programs. 展开更多
关键词 composite materials structural applications PREPREG technology automatic LAY-UP PROCESSES high production VOLUME rate
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Combinative Algorithms for the Multidisciplinary Collaborative Simulation of Complex Mechatronic Products Based on Major Step and Convergent Integration Step 被引量:6
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作者 LIANG Silue ZHANG Heming WANG Hongwei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第3期355-363,共9页
Multidisciplinary collaborative simulation (MCS) is an important area of research in the domain of multidisciplinary design optimization (MDO).Although previous research for MCS has to some extent addressed some i... Multidisciplinary collaborative simulation (MCS) is an important area of research in the domain of multidisciplinary design optimization (MDO).Although previous research for MCS has to some extent addressed some issues like using of multiple tools,integration stability,control of step size,data synchronization,etc,further work is still necessary to study how to achieve improved precision.A theoretical model is formulated to describe and analyze the integration process of MCS.A basic algorithm with equal major steps is proposed based on the model,along with two methods of implementation for the model,namely the serial method and the parallel method.A further algorithm based on convergent integration step is proposed,which has a more flexible strategy for run-time integration.The influence of interpolation techniques on simulation performance is studied as well.Simulations of the performance of various algorithms with different interpolation techniques are performed for both a simple numerical example and a complex mechatronic product.The novel algorithm based on convergent integration step,when used with a high-order interpolation technique,has better performance in terms of precision and efficiency.The innovation of this paper is mainly on the validation of high precision of the proposed convergent integration step algorithm. 展开更多
关键词 mechatronic product multidisciplinary collaborative simulation multi-rate integration convergent integration step
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Heat Production Rate Calculation of Thermal Manikin with a Compensation Method
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作者 朱利军 张渭源 +1 位作者 陈文飞 陈景山 《Journal of China Textile University(English Edition)》 EI CAS 2000年第1期79-81,共3页
Thermal manikin plays important roles in simulating thethermal state of human bodies to facilitate the evaluationof thermal comfort properties of various clothing assem-blies.Based on the heat balance principle and an... Thermal manikin plays important roles in simulating thethermal state of human bodies to facilitate the evaluationof thermal comfort properties of various clothing assem-blies.Based on the heat balance principle and analysis ofrelated factors,the heat production rate of manikin isrecommended as an efficient evaluation index.Whereas,its inside heat production which occurs as a result of theexistence of temperature difference between its insidepart and outside surface,should not be ignored.Through a series of theoretical analysis and calculations,a compensative equation is deduced in this paper. 展开更多
关键词 thermal MANIKIN HEAT balance non - evapora-tive HEAT loss HEAT productION rate INNER HEAT productION rate CALCULATION compensation.
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Solution for slab forging with bulge between two parallel platens by strain rate vector inner-product integration and series expansion 被引量:3
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作者 赵德文 王磊 +1 位作者 刘相华 王国栋 《中国有色金属学会会刊:英文版》 EI CSCD 2005年第5期1009-1013,共5页
A new linear integration was developed. First, effective strain rate for slab forging with bulge was expressed in terms of two-dimensional strain rate vector, and its inner-product was integrated term by term. Second,... A new linear integration was developed. First, effective strain rate for slab forging with bulge was expressed in terms of two-dimensional strain rate vector, and its inner-product was integrated term by term. Second, a summation process of term by term integrated results and a formula of the bulging were introduced, and an analytical solution of stress effective factor was obtained. It is proved that the expression of power by the above linear integration is the same as that of traditional immediate integration. Also, the solution was simplified by series expansion and compared by slab forging test with the others. It turns out that the calculated result of total forging pressure is basically in agreement with measured value in the actual press test. 展开更多
关键词 金属加工 压力加工 应力 线性整合 速率
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ENTROPY PRODUCTION RATE OF THE MINIMAL DIFFUSION PROCESS
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作者 章复熹 钱敏 《Acta Mathematica Scientia》 SCIE CSCD 2007年第1期145-152,共8页
The entropy production rate of stationary minimal diffusion processes with smooth coefficients is calculated. As a byproduct, the continuity of paths of the minimal diffusion processes is discussed, and that the point... The entropy production rate of stationary minimal diffusion processes with smooth coefficients is calculated. As a byproduct, the continuity of paths of the minimal diffusion processes is discussed, and that the point at infinity is absorbing is proved. 展开更多
关键词 Minimal diffusion process entropy production rate continuous path
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Genetic Toxic Effects of Rare-earth Waste and Its Products on Peacock Fish
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作者 ZHANGYing LIUShi-ying +1 位作者 WUYi-ning DUChang-jie 《Journal of Northeast Agricultural University(English Edition)》 CAS 2003年第2期101-104,共4页
The micro-nuclei and abnormal nuclei rates of peacock fish are tested,genetic toxic effects of rare-earth waste and its products(cement,plastic) on peacock in water are investigated.Results show that the leachate of r... The micro-nuclei and abnormal nuclei rates of peacock fish are tested,genetic toxic effects of rare-earth waste and its products(cement,plastic) on peacock in water are investigated.Results show that the leachate of rare-earth waste can lead to micronuclei and abnormal nuclei rates of peacock fish an obvious increase(P<0.01). Products made of the waste cause the micronuclei rate to be increased because of its low radio active action,but the change in abnormal nuclei rate can't reach a remarkable level.It shows that rare-earth waste has a certain effect of causing mutation on aquatic organism.Harmfulness of products made from this waste is decreased largely,and resources can be effectively saved. 展开更多
关键词 rare-earth waste products made from waste peacock fish micronuclei-rate abnormal nuclei rate
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Influence of depressurization rate on gas production capacity of high-rank coal in the south of Qinshui Basin, China
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作者 SU Xuefeng LIU Yan +3 位作者 CUI Zhouqi ZHANG Jianguo YU Li WANG Kai 《Petroleum Exploration and Development》 2019年第3期642-650,共9页
A desorption simulation experiment with the condition of simulated strata was designed. The experiment, under different depressurizing rates and the same fluid saturation, was conducted on the sample from 3# coal of D... A desorption simulation experiment with the condition of simulated strata was designed. The experiment, under different depressurizing rates and the same fluid saturation, was conducted on the sample from 3# coal of Daning coal mine in Jincheng, Shanxi Province. The gas production rate and pressure change at both ends of the sample were studied systematically, and the mechanisms of some phenomena in the experiment were discussed. The experimental results show that, whether at fast or slow depressurizing rate, the methane adsorbed to high-rank coal can effectively desorb and the desorption efficiency can reach above 90%. There is an obvious inflection point on the gas yield curve during the desorption process and it appears after the pressure on the lump of coal reduces below the desorption pressure. The desorption of methane from high-rank coal is mainly driven by differential pressure, and high pressure difference is conducive to fast desorption. In the scenario of fast depressurization, the desorption inflection appears earlier and the gas production rate in the stage of rapid desorption is higher. It is experimentally concluded that the originally recognized strategy of long-term slow CBM production is doubtful and the economic benefit of CBM exploitation from high-rank coal can be effectively improved by rapid drainage and pressure reduction. The field experiment results in pilot blocks of Fanzhuang and Zhengzhuang show that by increasing the drainage depressurization rate, the peak production of gas well would increase greatly, the time of gas well to reach the economic production shortened, the average time for a gas well to reach expected production reduced by half, and the peak gas production is higher. 展开更多
关键词 Qinshui Basin Fanzhuang BLOCK Zhengzhuang BLOCK high-rank COAL DEPRESSURIZATION rate gas production rate simulation experiment gas production capacity
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Warranty Cost Model Based on Optimal Preventive Maintenance Operations for Repairable Products 被引量:1
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作者 周炳海 王佳跃 潘尔顺 《Journal of Donghua University(English Edition)》 EI CAS 2009年第6期575-579,共5页
Most warranty cost models based on preventive maintenance operations are assumed that products improve at each preventive maintenance(PM)operation and the failure rate is reduced to the failure rate of new products or... Most warranty cost models based on preventive maintenance operations are assumed that products improve at each preventive maintenance(PM)operation and the failure rate is reduced to the failure rate of new products or to some specified level.To make warranty cost models more suitable to real operations,a modeling method of the PM warranty cost was proposed with the situation where each PM operation slowed the rate of product degradation.A warranty cost model was built on PM operations.On the basis of the cost model,both without and with reliability limit PM warranty policy,algorithms were presented to derive the optimal PM number and the optimal PM interval with an objective of minimizing expected total warranty cost over a finite warranty period.Finally,to demonstrate the feasibility of the presented modeling method,Weibull distribution cases were tested by numerical simulations.The simulation results indicate that the proposed modeling method is feasible and valid for resolving the optimal solution of the product warranty cost. 展开更多
关键词 保修政策 费用模型 预防性维修 产品 成本模型 预防性维护 运算 建模方法
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Expressions for Entropy Production Rate of Fuel Cells 被引量:2
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作者 Tong-ling Lin Ying-ru Zhao Jin-can Chen 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第4期361-366,共6页
根据燃料房间的一个一般模型,在不同条件下面的一个燃料房间系统的熵生产率被使用电气化学和热力学的理论导出。以便分析在一个实际燃料房间存在的不可逆的损失的影响,燃料房间的相等的电路被介绍以便燃料房间的不可逆的因素可能作为... 根据燃料房间的一个一般模型,在不同条件下面的一个燃料房间系统的熵生产率被使用电气化学和热力学的理论导出。以便分析在一个实际燃料房间存在的不可逆的损失的影响,燃料房间的相等的电路被介绍以便燃料房间的不可逆的因素可能作为功能直接坚定内部,漏缝和负载电阻。而且,燃料房间的最大的力量产量和效率被计算,燃料房间的最佳的操作被讨论,并且负担抵抗的匹配的条件是坚定的。 展开更多
关键词 燃料电池 生产率 电化学分析 生产技术
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