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Carbon isotope ratios of n-alkanoic acids: new organic proxies for paleo-productivity in Antarctic ponds
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作者 CHEN Xin JIN Jing +5 位作者 NIE Yaguang ZHANG Jifeng DONG Liang HUANG Xianyu Steven D()EMSLIE LIU Xiaodong 《Advances in Polar Science》 CSCD 2023年第4期304-317,共14页
Primary productivity in the Antarctic aquatic environment with simple ecosystems is sensitive to climate and environmental fluctuations.We investigatedδ13C values for n-alkanoic acids derived from phototrophic organi... Primary productivity in the Antarctic aquatic environment with simple ecosystems is sensitive to climate and environmental fluctuations.We investigatedδ13C values for n-alkanoic acids derived from phototrophic organisms in a lacustrine sediment core(IIL3)to indicate primary productivity in ponds on Inexpressible Island in the western Ross Sea,Antarctica.Short-chain n-alkanoic acids(C14–C18)were abundant in the IIL3 sediment profile.The carbon isotope ratios of short-chain n-alkanoic acids in the sediment samples and floating microbial mats were similar,indicating that the short-chain n-alkanoic acids in the IIL3 sediment profile predominantly originated from phototrophic organisms.Theδ13C values for the short-chain n-alkanoic acids varied widely through the sediment profile,and 13C-enrichment of n-alkanoic acids was most likely related to high productivity due to carbon-limited conditions caused by enhanced photosynthetic efficiency.Theδ13C values for the n-alkanoic acids changed over the past 3200 years in similar ways to organic proxies for aquatic productivity(n-alkanoic acid and sterol sedimentary fluxes).C16 n-alkanoic acid was enriched in 13C in periods of high aquatic productivity~750–1650 and 3000–3200 a BP but depleted in 13C in periods of relatively low productivity~150–600 and 2500–3000 a BP.The results indicated that carbon isotope ratios of lipids from phototrophic organisms could be used as new proxies to reconstruct paleo-productivity in Antarctic lakes and ponds and therefore improve our understanding of past climate changes. 展开更多
关键词 East Antarctica lipid biomarkers carbon isotopic ratios pond primary productivity climate change
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Effects of Different Row Ratios of Male and Female Parents and Application Amount of Nitrogen Fertilizer on Hybrid Wheat Seed Production and Its Component Factors 被引量:1
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作者 Can SUN Renwu RUAN +7 位作者 Lili YAN Dan HU Xingbei LIU Hengzhi SHE Manman XU Zhongan LI Zelin YI Yuheng YANG 《Asian Agricultural Research》 2017年第3期69-73,共5页
In order to screen suitable high hybrid wheat seed production technology,the split-plot experiment design was adopted and study was carried out about the effects of the different row ratios of male and female parents ... In order to screen suitable high hybrid wheat seed production technology,the split-plot experiment design was adopted and study was carried out about the effects of the different row ratios of male and female parents and application amount of nitrogen fertilizer on hybrid wheat seed production and its component factors. The results showed that the seed production increased with the increase in the number of female parent row. When the row ratio of male and female parents was 2 ∶ 6,the seed production was 3 683. 8 kg/ha; when the application amount of nitrogen fertilization was 50 kg/ha,the seed production was 3 649. 4 kg/ha; the interaction between the row ratio of male and female parents and the application amount of nitrogen fertilizer indicated that when the row ratio of male and female parents was 2∶ 6 and the application amount of nitrogen fertilizer was 300 kg/ha,the seed production reached the highest( 4160. 6 kg/ha). The row ratio of male and female parents and application amount of nitrogen fertilizer had significant effect on the component factors of seed production,including the number of grains per spike,spike weight and setting percentage. When the row ratio of male and female parents was 2∶ 5,the number of grains per spike,spike weight and setting percentage were the highest at 26. 7 grains,1. 12 g,and 62. 6% respectively; when application amount of nitrogen fertilizer was 450 kg/ha,the number of grains per spike,spike weight and setting percentage were the highest at 26. 0 grains,1. 08 g,and59. 2% respectively; the interaction of row ratio of male and female parents and application amount of nitrogen fertilizer had significant effect on the number of grains per spike,spike weight and setting percentage; when the row ratio of male and female parents was 2∶ 5 and the application amount of nitrogen fertilizer was 300 kg/ha,the number of grains per spike,spike weight and setting percentage were the highest at 29. 6grains,1. 24 g,and 71. 6% respectively. The number of grains per spike is the largest component factor for seed production. Increasing the number of grains per spike can increase the seed production. According to the effects of row ratio of male and female parents and application amount of nitrogen fertilizer on the component factors of seed production,the optimal condition was 2∶ 5-2∶ 6 for row ratio of male and female parents and 300-450 kg/ha for application amount of nitrogen fertilizer. 展开更多
关键词 Hybrid wheat Row ratio of male and female parents Nitrogen fertilizer Seed production
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Automatic Detection Instrument for the Ratio of Chlorine to Bromine in Oxidized Liquid of Bromine Production Based on Fuzzy Method
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作者 Yu Naigong Wang Kaiyan 《仪器仪表学报》 EI CAS CSCD 北大核心 2006年第z1期159-161,共3页
In the process of bromine production,because of lag adjustment methods,there are problems of adjusting delay,raw material wastage and low growth rate.By considering the nature of bromine production,with the help of fu... In the process of bromine production,because of lag adjustment methods,there are problems of adjusting delay,raw material wastage and low growth rate.By considering the nature of bromine production,with the help of fuzzy data processing method,computer detection and display technique,we designed an automatic detection instrument for the ratio of chlorine to bromine in oxidized liquid of bromine production.This instrument can be used to detect the different parameters of raw materials adjustment and control in real time,and afford assurance that raw materials will be adjusted in time.This paper briefly introduces the working mechanism,hardware and software design of the instrument. 展开更多
关键词 BROMINE production fuzzy relation list ratio of CHLORINE to BROMINE in OXIDIZED LIQUID OXIDIZING electric potential automatic detection
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Effect of Pelleted Total Mixed Ration with Different Concentrate-roughage Ratios on Production Performance and Serum Biochemical Parameters of Fattening Hainan Black Goats
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作者 Liu Quanwei Wang Feng +5 位作者 Wei Limin Tan Shuyi Sun Ruiping Huang Lili Xing Manping Zheng Xinli 《Animal Husbandry and Feed Science》 CAS 2019年第1期4-8,共5页
[Objective] This paper was to study effects of pelleted total mixed ration with different concentrate-roughage ratios on production performance and serum biochemical parameters of fattening Hainan black goats.[Method]... [Objective] This paper was to study effects of pelleted total mixed ration with different concentrate-roughage ratios on production performance and serum biochemical parameters of fattening Hainan black goats.[Method] Thirty-six fattening Hainan black goats with the same genetic background and similar initial weight of(14.08±0.13) kg were randomly assigned into three treatments. Goats were fed with Juncao + concentrate(control group), pelleted total mixed ration I(concentrate: roughage 50 ∶50, group Ⅰ) and Ⅱ(concentrate: roughage 45∶55, group Ⅱ), respectively. The test lasted 45 d.[Result] The final weight, daily gain and feed intake of rams in experimental group Ⅰ were significantly higher than those of control group and experimental group Ⅱ(P<0.05);the final weight and daily gain of rams in experimental group Ⅰ were also markedly higher than those of experimental group Ⅱ(P<0.05);the feed/gain of rams in experimental group Ⅰ was significantly lower than those in control group and experimental group Ⅱ(P<0.05). The feed gain cost of rams in experimental group Ⅰ was markedly lower than that in experimental group Ⅱ( P<0.05), but was significantly higher than that in experimental group Ⅰ(P<0.05);the gross profit of rams in experimental group Ⅰ was significantly higher than those in control group and experimental group Ⅱ(P<0.05). Compared with control group and experimental group Ⅱ, the serum total protein and glucose lev-els in experimental group Ⅱ increased significantly(P<0.05), but the urea nitrogen content reduced(P>0.05).[Conclusion] When the concentrateroughage ratio of pelleted total mixed ration was 50∶50, the fattening effect of Hainan black goat was better, and the serum total protein and glucose levels were evidently improved. 展开更多
关键词 FATTENING HAINAN black GOAT Pelleted total mixed ration Concentrate-roughage ratio production performance SERUM BIOCHEMICAL parameters
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Effects of salinity on egg and fecal pellet production, development and survival, adult sex ratio and total life span in the calanoid copepod, A cartia tonsa:a laboratory study 被引量:1
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作者 SHAYEGAN Majid ESMAEILI FEREIDOUNI Abolghasem +1 位作者 AGH Naser JANI KHALILI Khosrow 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第4期709-718,共10页
The ef fects of salinity on the copepod, A cartia tonsa in terms of daily egg production rate(EPR), hatching success, fecal pellet production rate(FPR), naupliar development time and survival, sex ratio, and total lif... The ef fects of salinity on the copepod, A cartia tonsa in terms of daily egg production rate(EPR), hatching success, fecal pellet production rate(FPR), naupliar development time and survival, sex ratio, and total life span were determined in laboratory conditions through three experiments. In experiment 1, EPR, hatching success, and FPR of individual females were monitored at salinities of 13, 20, 35 and 45 during short-periods(seven consecutive days). Results show EPR was aff ected by salinity with the highest outputs recorded at 20 and 35, respectively, which were considerably higher than those at 13 and 45. Mean FPR was also higher in 35 and 20. In experiment 2, the same parameters were evaluated over total life span of females(long-term study). The best EPR and FPR were observed in 35, which was statistically higher than at 13 and 20. In experiment 3, survival rates of early nauplii until adult stage were lowest at a salinity of 13. The development time increased with increasing of salinity. Female percentage clearly decreased with increasing salinity. Higher female percentages(56.7% and 52.2%, respectively) were signifi cantly observed at two salinities of 13 and 20 compared to that at 35(25%). Total longevity of females was not af fected by salinity increment. Based on our results, for mass culture we recommend that a salinity of 35 be adopted due to higher reproductive performances, better feeding, and faster development of A. tonsa. 展开更多
关键词 实验室条件 桡足类 产蛋率 生产率 盐度 寿命 粪便 孵化成功率
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Biohydrogen Production from Synthetic Waste Co-digested with Liquid Dairy Cow Manure: Effect of Temperature and Mixing Ratio
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作者 S. A. Lateef T. Yamashiro N. Beneragama M. Iwasaki Y. Moriya C. Ying K. Umetsu 《Journal of Agricultural Science and Technology(A)》 2011年第8期1303-1306,共4页
关键词 生物制氢 固体废物 基板温度 奶牛粪 消化 混合率 挥发性固体 液态
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Hydrogen Production by Coal Gasification Coupled with <i>in Situ</i>CO<sub>2</sub>Capture 被引量:1
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作者 Xun Wang 《Energy and Power Engineering》 2012年第4期210-217,共8页
CO2 adsorption enhanced gasification process is a prospective technology to be used in hydrogen production with nearly zero CO2 emission. In this paper, a gasification kinetics steady state model is developed based on... CO2 adsorption enhanced gasification process is a prospective technology to be used in hydrogen production with nearly zero CO2 emission. In this paper, a gasification kinetics steady state model is developed based on the chemical kinetics mechanism with the condition of fluidization. It is used to predict the parameters of gas phase and solid phase for a continuous flow reactor with steady state. The variation of components distribution with gasification temperature and pressure are determined, from which the optimal operation parameters of gasifier can be obtained. 展开更多
关键词 Kinetics Modeling GASIFICATION Temperature and Pressure products COMPOSITIONS Conversion ratio
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Influence of Pt/Ru anodic ratio on the valorization of ethanol by PEM electrocatalytic reforming towards value-added products 被引量:1
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作者 Alberto Rodriguez-Gomez Fernando Dorado +1 位作者 Antonio de Lucas-Consuegra Ana Raquel de la Osa 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第5期264-275,共12页
The ethanol electro-reforming process was studied over PtRu/C catalysts synthesized by the modified polyol method with different compositions.In particular,this work reports the influence of anodic Pt:Ru ratio(5:1,2:1... The ethanol electro-reforming process was studied over PtRu/C catalysts synthesized by the modified polyol method with different compositions.In particular,this work reports the influence of anodic Pt:Ru ratio(5:1,2:1 and 1:2)on the organic product distribution(acetaldehyde,acetic acid and ethyl acetate)and pure hydrogen generation at different current densities operation levels.Physicochemical characterization of the catalysts was made by X-ray diffraction(XRD),temperature-programmed reduction(TPR)and N_(2) adsorption-desorption measurements.XRD patterns showed that Ru is introduced into the Pt structure,forming an alloy between both metals.Also,the degree of alloy was higher by increasing the Ru amounts.From TPR profiles Pt was found to be properly reduced while Ru was both in metallic state and forming RuO2.The electrochemical behaviour of each catalyst towards ethanol electroreforming process was investigated through electrochemical techniques in a half cell and a single proton exchange membrane(PEM)cell systems.An intermediate Pt:Ru ratio was found to result in high current density and electrochemical surface area(ECSA)values along with lower amounts of adsorbed species.Also,Ru addition seems to diminish the degree of degradation of the catalyst.Based on characterization and in agreement with essays carried out in a PEM cell at mild conditions(80℃ and 1 atm),PtRu/C 2:1 anode provided the best electrocatalytic results in terms of current density(740 mA cm^(-2)),hydrogen production and selectivity toward acetic acid(up to 15%apart from acetaldehyde and ethyl acetate)while requiring the lowest energy consumption. 展开更多
关键词 Ethanol electro-reforming PEM cell Pt:Ru anodic ratio Hydrogen production Value-added liquid product distribution
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ANNUAL PRODUCTION OF FIVE SPECIES OF CHIRONOMIDAE (DIPTERA)IN HOUHU LAKE,A TYPICAL ALGAL LAKE(WUHAN,CHINA) 被引量:6
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作者 阎云君 梁彦龄 王洪铸 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1999年第2期112-118,共7页
Annual production and life cycle of five dominant species of Chironomidae (Chironomus plumosus, Cryptochironomus sp., Tokunagayusurkia akamusi, Procladius sp.,Clinotanypus sp )were studied with samples collected month... Annual production and life cycle of five dominant species of Chironomidae (Chironomus plumosus, Cryptochironomus sp., Tokunagayusurkia akamusi, Procladius sp.,Clinotanypus sp )were studied with samples collected monthly from April, 1996 to March, 1997 in Houhu Lake at four stations. Based on instar-frequency data, C. plumosus was nnivoltine, while the other four were bivoltine.Production rates in grams wet weight m-2 a-1 calculated by the size-frequency method were C.plumosus,2.170; Cryptochironomus sp., 0. 602; T. akamusi, s. 160; Procladius sp., 0. 964; Clinotanypussp., 0.390. Their P/B ratios were 3.9, 4.9, 4.4, 5.3 and 6.6, respectively. 展开更多
关键词 CHIRONOMIDAE ANNUAL producation P/B ratio size-frequency method Houhu LAKE
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Secondary Production of Macrobenthos in Mangrove Area of Tong'an Bay,China 被引量:2
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作者 ZHOU Xiping CAI Lizhe 《Journal of Ocean University of China》 SCIE CAS 2010年第2期151-156,共6页
Studies on secondary production lead to a better understanding of the functions of the macrobenthic ecosystem.Basedon the macrobenthic data obtained at 6 sampling stations from April 2006 to January 2007,Brey's(19... Studies on secondary production lead to a better understanding of the functions of the macrobenthic ecosystem.Basedon the macrobenthic data obtained at 6 sampling stations from April 2006 to January 2007,Brey's(1990)empirical formula wasapplied to calculate the secondary production of macrobenthos in the mangrove area of Tong'an Bay.The results showed that themean annual secondary production of macrobenthos was 13.24 gAFDWm-2-a-1.The mean secondary production in the mangrovehabitat was 12.22 gAFDWm-2-a-1,lower than that in the non-mangrove habitat,which was 15.29 gAFDWm-2-a-1.Two possible rea-sons existed for this difference.First,mollusk and crustacean,which contribute more to the secondary production,probably benefitfrom longer inundation period in the non-mangrove habitat.Second,the higher organic matter in the mangrove habitat results in hy-poxia in the bottom sediment,which may decrease the secondary production.The annual mean production-to-biomass(P/B)ratio inTong'an Bay was 1.17,with a ratio of 1.27 in the mangrove habitat and 0.96 in the non-mangrove habitat,which was coincident withthe much higher density of Limnodriloides sp.and Corophium sp.in the mangrove habitat than in the non-mangrove habitat.Themaximum secondary production and P/B ratio of macrobenthos both appeared at sampling station FL2 in April,2006(namelyApril-FL2)with values of 31.38 gAFDWm-2-a-1and 2.20,respectively.The macrobenthic secondary production in Tong'an Bay islower than those in other intertidal studies except that in Haitan Strait,the reason being the different sediment properties.The P/Bratio in Tong'an Bay was the lowest due to the high proportion of crustaceans in the macrobenthic community. 展开更多
关键词 大型底栖动物 同安湾 红树林 生产 二级 面积 中国
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LIFE CYCLE AND PRODUCTION OF CHIRONOMIDAE(DIPTERA) IN BIANDANTANG, A TYPICAL MACROPHYTIC LAKE (HUBEI, CHINA)
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作者 阎云君 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2000年第3期221-226,共6页
The life cycle and annual production of four dominant species of Chironomids ( Chironomus plumosus, Chironomus sp., Clinotanypus sp., Tokunagayusurika akamusi) were studied with samples taken monthly in Biandantang La... The life cycle and annual production of four dominant species of Chironomids ( Chironomus plumosus, Chironomus sp., Clinotanypus sp., Tokunagayusurika akamusi) were studied with samples taken monthly in Biandantang Lake at eight stations from April, 1996 to March, 1997. Instar frequency data showed C. plumosus was univoltine, while the other three were bivoltine. Production in wet weight (g/(m 2·a)) calculated by the size frequency method for each species were: C. plumosus, 2.663 ; Chironomus sp.,1.161 ;Clinotanypus sp., 0.270; T. akamusi , 1.476. Based on the mean standing stock, their P/B ratios were 3.2, 4.0, 6.2 and 4.4, respectively. 展开更多
关键词 DIPTERA CHIRONOMIDAE life cycle production P/B ratio size frequency method Biandantang LAKE
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ANALYSES OF THE DIFFERENCE BETWEEN IRRIGATED AND NONIRRIGATED AREA FOR LUMINOUS ENERGY UTILIZATION RATIO AND PRODUCTIVE POTENTIALITIES IN NINGXIA
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作者 Sun Fulu Ningxia Center of Climatological Date 《干旱区资源与环境》 CSCD 1993年第Z1期391-396,共6页
Situated in arid and semi-arid lands, the Ningxia Hui Autonomous Region is locatedat the middle reaches of the Yellow River. An adequate system of gravity irrigation was es-tablished in the north of Ningxia. Adding to... Situated in arid and semi-arid lands, the Ningxia Hui Autonomous Region is locatedat the middle reaches of the Yellow River. An adequate system of gravity irrigation was es-tablished in the north of Ningxia. Adding to abundant sunshine, strong solar radiation andmoderate heat, the agriculture is very developed. The south mountainous area of Ningxia, including both Yanchi and Tongxin counties,is short of rain, The vast lands cannot be irrigated. Nonirrigated agriculture and 展开更多
关键词 IRRIGATED AGRICULTURE RAINFED AGRICULTURE LUMINOUS Energy Utilization ratio productive POTENTIALS
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Appraisement on Contributive Ratio of Scientific and Technical Progresses in Milk Productive Enterprises by Model C^2GS^2
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作者 SUN Futian SUN Liqun YANG Guanglin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第4期41-44,共4页
Scientific and technical progress has been the driving forces of enterprises development.Milk productive enterprises are developing faster and growing better.It is very important to measure the contributive ratio of s... Scientific and technical progress has been the driving forces of enterprises development.Milk productive enterprises are developing faster and growing better.It is very important to measure the contributive ratio of scientific and technical progress in milk productive enterprises.And the appraisement could help to develop milk productive enterprises.The model C^2GS^2 was established to appraise the contributive ratio of scientific and technical progress in milk productive enterprises in the research.And the appraisement on the contributive ratio of scientific and technical progress in milk productive enterprises was made by the model.In the results of appraisement,science and technology play a main role in milk productive enterprises.It is shown that our milk productive enterprises are developed by scientific and technical progress while not by input of productive factors. 展开更多
关键词 model C^2GS^2 milk productive enterprises APPRAISEMENT contributive ratio
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IMF production and symmetry energy in heavy ion collisions near Fermi energy 被引量:5
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作者 WADA Roy HUANG Meirong +3 位作者 LIN Weiping LIU Xingquan ZHAO Minghui CHEN Zhiqiang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2013年第5期1-6,共6页
The symmetry energy at the time of the production of intermediate mass fragments(IMFs) is studied using experimentally observed IMF multiplicities combined with quantum statistical model calculations(QSM of Hahn and S... The symmetry energy at the time of the production of intermediate mass fragments(IMFs) is studied using experimentally observed IMF multiplicities combined with quantum statistical model calculations(QSM of Hahn and St cker).The ratios of difference in chemical potentials between neutrons and protons relative to the temperature,(μn-μp)/T,and the double ratio temperature,T,were extracted experimentally in the reactions of64,70Zn,64Ni+58,64Ni,112,124Sn,197Au,232Th at 40A MeV.The extracted(μn-μp)/TTscales linearly with δNN,where δNN is the asymmetry parameter,(N-Z)/A,of the emitting source and(μn-μp)/T=(11.1 1.4)δNN0.21 was derived.The experimentally extracted(μn-μp)/T and the double ratio temperatures are compared with those from the QSM calculations.The temperatures-,T,and densities,ρ,extracted from the(μn-μp)/T values agreed with those from the double ratio thermometer which used the yield ratios of d,t,h and α particles.However the two analyses of the differential chemical potential analysis and the initial temperature analysis end up almost identical relation between T and ρ.T=5.25±0.75 MeV is evaluated from the(μn-μp)/Tanalysis,but no density determination was possible.From the extracted T value,the symmetry energy coefficient Esym =14.6±3.5 MeV is determined for the emitting source of T=5.25±0.75 MeV. 展开更多
关键词 国际货币基金组织 对称能 重离子碰撞 生产 费米能 量子统计模型 实验观察 中等质量碎片
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Effects of Different Breeds,Number of Squabs and Temperature on Production Performance of Pigeons
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作者 Qingping TANG Chunyu MU +2 位作者 Zuofu QU Rui ZHANG Zhu BU 《Asian Agricultural Research》 2019年第10期76-79,共4页
To explore the effects of breeds,number of nurturing squabs,and temperature on nest feed conversion ratio and analyze the effects of number of nurturing squabs on parent pigeon body mass,fertility rate,and laying inte... To explore the effects of breeds,number of nurturing squabs,and temperature on nest feed conversion ratio and analyze the effects of number of nurturing squabs on parent pigeon body mass,fertility rate,and laying intervals,5 widely used breeds of pigeon were nurtured under the condition of natural laying and hatching in this research.In each breed,24 pair pigeons nurturing 1,2,3,and 4 squabs were chosen to measure the production performance,respectively.The results indicated that different numbers of nurturing squabs had a significant effect on parent pigeon body mass changes and survival rate of 28-d old squabs(P<0.05);the nest feed conversion ratio of breeds nurturing 1 squab(7.58)was extremely significantly higher than those of nurturing 2,3,and 4 squabs(P<0.01);the nest feed conversion ratio of breeds nurturing 2 squabs(4.75)was extremely significantly higher than those of nurturing 3(3.95)and 4 squabs(3.75)(P<0.01);there was no significant difference between breeds nurturing 3 and 4 squabs(P>0.05).Laying intervals of breeds nurturing 4 squabs(43.8 d)were significantly higher than those of nurturing 3(37.4 d),2(35.4 d),and 1(33.8 d)squabs(P<0.05).Nest feed conversion ratio significantly increased with the decrease of environment temperature(P<0.05).The breed showed no effect on the nest feed conversion ratio.In production,nurturing 3 squabs of parent pigeons is appropriate.In some cold areas in winter,cold protection measures should be taken. 展开更多
关键词 PIGEON NUMBER of nurturing squabs Temperature NEST FEED conversion ratio production performance
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Ratio-Cum-Product Estimator Using Multiple Auxiliary Attributes in Single Phase Sampling 被引量:4
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作者 John Kung’u Leo Odongo 《Open Journal of Statistics》 2014年第4期239-245,共7页
In this paper, we have proposed a class of ratio-cum-product estimator for estimating population mean of study variable for single phase sampling using multi-auxiliary attributes. The expressions for mean square error... In this paper, we have proposed a class of ratio-cum-product estimator for estimating population mean of study variable for single phase sampling using multi-auxiliary attributes. The expressions for mean square error are derived. An empirical study is given to compare the performance of the estimator with existing estimators. It has been found that the ratio-cum-product estimator using multiple auxiliary attributes is more efficient than mean per unit, product and ratio estimators using one auxiliary attribute, and Product and Ratio estimators using multiple auxiliary attributes in single phase sampling. 展开更多
关键词 ratio-Cum-product ESTIMATOR MULTIPLE AUXILIARY Attributes Single Phase Sampling Bi-Serial Correlation Coefficient
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Intrinsic product polarization and branch ratio in the S(~1D,~3P)+HD reaction on three electronic states
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作者 李琳 董顺乐 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期319-323,共5页
The intrinsic product polarization and intramolecular isotope effect of the S(~1D,~3P) + HD reaction have been investigated on both the lowest singlet state(1A) and the triplet state(3A and 3A) potential energy... The intrinsic product polarization and intramolecular isotope effect of the S(~1D,~3P) + HD reaction have been investigated on both the lowest singlet state(1A) and the triplet state(3A and 3A) potential energy surfaces by using quasi-classical trajectory and quantum mechanical methods.The calculations indicate that intramolecular isotope effects are different on the three electronic states.The stereodynamics study shows that the P(θr) distributions,P(φ r) distributions,and polarization-dependent differential cross sections(PDDCSs)(00) are sensitive to mass factor and the product angular momentum vectors are not only aligned but also oriented. 展开更多
关键词 quasi-classical trajectory quantum mechanics product polarization branch ratio
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A Novel PSO Algorithm for Optimal Production Cost of the Power Producers with Transient Stability Constraints
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作者 M. ANITHA S. SUBRAMANIAN R. GNANADASS 《Journal of Electromagnetic Analysis and Applications》 2009年第4期265-274,共10页
The application of a novel Particle Swarm Optimization (PSO) method called Fitness Distance Ratio PSO (FDR PSO) algorithm is described in this paper to determine the optimal power dispatch of the Independent Power Pro... The application of a novel Particle Swarm Optimization (PSO) method called Fitness Distance Ratio PSO (FDR PSO) algorithm is described in this paper to determine the optimal power dispatch of the Independent Power Producers (IPP) with linear ramp model and transient stability constraints of the power producers. Generally the power producers must respond quickly to the changes in load and wheeling transactions. Moreover, it becomes necessary for the power producers to reschedule their power generation beyond their power limits to meet vulnerable situations like credible contingency and increase in load conditions. During this process, the ramping cost is incurred if they violate their permissible elastic limits. In this paper, optimal production costs of the power producers are computed with stepwise and piecewise linear ramp rate limits. Transient stability limits of the power producers are also considered as addi-tional rotor angle inequality constraints while solving the Optimal Power Flow (OPF) problem. The proposed algo-rithm is demonstrated on practical 10 bus and 26 bus systems and the results are compared with other optimization methods. 展开更多
关键词 OPTIMAL Power Flow production COST RAMPING COST Fitness Distance ratio Particle Swarm Optimization Transient Stability LIMIT PIECEWISE Linear RAMP Rate LIMIT
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Cost of Production at Business Unit in Aquaculture Industry: Study at Aquafarm Nusantara Company
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《Journal of Modern Accounting and Auditing》 2012年第5期671-678,共8页
关键词 水产养殖场 生产成本 养殖业 单位 业务 原料成分 价格计算 鱼饲料
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Ratio-Cum-Product Estimator Using Multiple Auxiliary Attributes in Two-Phase Sampling
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作者 John Kung’u Leo Odongo 《Open Journal of Statistics》 2014年第4期246-257,共12页
In this paper, we have proposed three classes of ratio-cum-product estimators for estimating population mean of study variable for two-phase sampling using multi-auxiliary attributes for full information, partial info... In this paper, we have proposed three classes of ratio-cum-product estimators for estimating population mean of study variable for two-phase sampling using multi-auxiliary attributes for full information, partial information and no information cases. The expressions for mean square errors are derived. An empirical study is given to compare the performance of the estimator with the existing estimator that utilizes auxiliary attribute or multiple auxiliary attributes. The ratio-cum-product estimator in two-phase sampling for full information case has been found to be more efficient than existing estimators and also ratio-cum-product estimator in two-phase sampling for both partial and no information case. Finally, ratio-cum-product estimator in two-phase sampling for partial information case has been found to be more efficient than ratio-cum-product estimator in two-phase sampling for no information case. 展开更多
关键词 ratio-Cum-product ESTIMATOR MULTIPLE AUXILIARY Attributes TWO-PHASE Sampling and Bi-Serial Correlation Coefficient
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