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Relative Efficiencies of Optimal Designs in Four Dimensions Constructed Using Balanced Incomplete Block Designs
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作者 Kabue Timothy Gichuki John Gikonyo Kiguta 《Open Journal of Statistics》 2024年第5期439-449,共11页
Experimentally, the best design gives estimates of the desired effects and contrasts with maximum precision. Efficiency as a discriminating factor enables comparison of designs. The goal of Response Surface Methodolog... Experimentally, the best design gives estimates of the desired effects and contrasts with maximum precision. Efficiency as a discriminating factor enables comparison of designs. The goal of Response Surface Methodology (RSM) is the determination of the best settings of the in-put variables for a maximum (or a minimum) response within a region of interest, R. This calls for fitting a model that adequately represents the mean response since such a model, is then used to locate the optimum. D-, A-, E- and T-Optimal designs of a rotatable design of degree two in four dimensions constructed using balanced incomplete block designs (BIBD) when the number of replications is less than three times the number of pairs of treatments occur together in the design and their relative efficiencies to general designs are presented. D-optimal design had 88 runs after replicating the factorial part twice and the axial part thrice with an optimal variance of 0.6965612 giving an efficiency of 97.7% while for A- and T-optimal designs they are formed with 112 runs each obtained by replicating the factorial part two times and axial part six times. Their optimal variances are 0.05798174 and 1.29828 respectively, with efficiency of 71.8% for A-optimal and 87.5% for T-optimal design. E-optimal design was found to be the most efficient design with an only 32 runs comprising only of the factorial part and with an optimal variance of 0.4182000, attaining an efficiency of approximately 1%. This study proposes the adoption of the E-optimal design in estimating the parameters of a rotatable second-order degree model constructed using BIBD for less costs and time saving. 展开更多
关键词 Response Surface Methodology Optimal Designs Relative Efficiency
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Zero Waste and Conversion Efficiencies of Various Technologies for Disposal of Municipal Solid Waste
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作者 张文阳 《Journal of Southwest Jiaotong University(English Edition)》 2005年第1期49-55,共7页
Zero waste is a philosophy and a design principle of dealing with our waste stream for the ~21st century. After reviewing the available information, the goal of zero waste from landfill is considered to be unachievabl... Zero waste is a philosophy and a design principle of dealing with our waste stream for the ~21st century. After reviewing the available information, the goal of zero waste from landfill is considered to be unachievable by using known and proven methods and ~approaches . The comparison of various technologies shows that the conversion efficiencies depend upon the type of system chosen for processing residual waste, and the best overall diversion rate of waste management system that can be achieved is about 71%. The maximum achievable overall diversion rate can be increased to approximate 92% if current environmental regulations to permit the routine use of the bottom ash or char for advanced thermal technologies. 展开更多
关键词 Municipal solid waste Zero waste Conversion efficiencies
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Phosphorus Uptake and Utilisation Efficiencies of Different Wheat Cultivars Based on a Sand-Culture Screening System 被引量:13
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作者 N.K.HOWES S.E.SMITH ZHUYONGGUAN 《Pedosphere》 SCIE CAS CSCD 2002年第4期329-337,共9页
A sand-based culture system using rock phosphate (P) was developed to simulate the situation in alkalinesoils, with respect to the dominant P form, and five wheat cultivars (Excalibur, Brookton, Krichauff, Westoniaand... A sand-based culture system using rock phosphate (P) was developed to simulate the situation in alkalinesoils, with respect to the dominant P form, and five wheat cultivars (Excalibur, Brookton, Krichauff, Westoniaand Sunco) were tested in this screening system to compare their P uptake and utilisation efficiencies. Resultsshowed that these cultivars differed significantly in their ability to acquire P from the sparingly available form(rock phosphate in this case). The accumulation of P by Brookton was three times that by Krichauff. Pconcentrations in plant tissues did not differ significantly, indicating that all cultivars were similar in Putilisation efficiency. A further experiment showed that the greater ability of a cultivar to take up P fromsparingly available form was related to the ability of a cultivar to acidify the rhizosphere. Seed P content wasa confounding factor in this system, and the use of relatively uniform seed with similar P content, preferablylow, was conducive to a successful outcome of the screening process. 展开更多
关键词 phosphorus efficiency sand-culture UPTAKE wheat genotypes
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Effect of biochar on grain yield and leaf photosynthetic physiology of soybean cultivars with different phosphorus efficiencies 被引量:9
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作者 ZHU Qian KONG Ling-jian +4 位作者 SHAN Yu-zi YAO Xing-dong ZHANG Hui-jun XIE Fu-ti AO Xue 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第10期2242-2254,共13页
This study was conducted with two soybean cultivars, Liaodou 13 (L13, phosphorus (P)-efficient) and Tiefeng 3 (T3, P-inefficient), to investigate the effects of biochar on soybean yield and photosynthetic physiologica... This study was conducted with two soybean cultivars, Liaodou 13 (L13, phosphorus (P)-efficient) and Tiefeng 3 (T3, P-inefficient), to investigate the effects of biochar on soybean yield and photosynthetic physiological parameters, at four biochar application rates (0, 1, 5, and 10%, w/w), and two fertilization treatments (0 and 150 kg ha–1). Grain yield, plant biomass, P accumulation, leaf net photosynthetic rate (Pn), chlorophyll index (Chl), nitrogen balance index (NBI), sucrose phosphate synthase (SPS), and sucrose synthase (SS) activities, soluble sugar, sucrose and starch contents, and leaf area duration (LAD) were measured. Biochar had positive effects on Pn, Chl, NBI, SPS, and SS activities, and leaf soluble sugar, sucrose, and starch contents of both genotypes, these effects increased with biochar application rate. L13 benefited more efficiently from biochar than T3 did, as the grain yield of L13 significantly increased by 31.0 and 51.0%, at 5 and 10% biochar, respectively, while that of T3 increased by 40.4 at 10% biochar application rate, as compared with controls. The combined application of biochar and fertilizer boosted the positive effects described, but no difference was found for grain yield in L13 among biochar application rates, while grain yield of T3 continually increased with biochar rate, among which, 1% biochar combined with 150 kg ha–1 fertilizer resulted in T3 yield increment of more than 23%, compared with the application of 150 kg ha–1 fertilizer alone. Altogether, our results indicated that the application of biochar enhanced carbon assimilation in soybean, resulting in increased biomass accumulation and yield. Differences in genotypic responses to biochar highlight the need to consider specific cultivars and biochar rate, when evaluating the potential responses of crops to biochar. 展开更多
关键词 BIOCHAR P efficiency PHOTOSYNTHESIS SOYBEAN yield
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Top-grain filling characteristics at an early stage of maize(Zea mays L.) with different nitrogen use efficiencies 被引量:12
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作者 SHEN Li-xia HUANG Yan-kai LI Ting 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第3期626-639,共14页
Maize genotypes vary significantly in their nitrogen use efficiencies(NUEs).Better understanding of early grain filling characteristics of maize is important,especially for maize with different NUEs.The objectives o... Maize genotypes vary significantly in their nitrogen use efficiencies(NUEs).Better understanding of early grain filling characteristics of maize is important,especially for maize with different NUEs.The objectives of this research were(i)to investigate the difference in apical kernel development of maize with different NUEs,(ii)to determine the reaction of apical kernel development to N application levels,and(iii)to evaluate the relationship between apical kernel development and grain yield(GY)for different genotypes of maize.Three maize hybrid varieties with different NUEs were cultivated in a field with different levels of N fertilizer arranged during two growing seasons.Kernel fresh weight(KFW),volume(KV)and dry weight(KDW)of apical kernel were evaluated at an early grain filling stage.Ear characteristics,GY and its components were determined at maturity stage.Apical kernel of the high N and high efficiency(HN-HE)type(under low N,the yield is lower,and under higher N,the yield is higher)developed better under high N(N210 and N240,pure N of 210 and 240 kg ha^–1)than at low N(N120 and N140,pure N of 120 and 140 kg ha^–1).The low N and high efficiency(LN-HE)type(under low N,the yield is higher,while under higher N,the yield is not significantly higher)developed better under low N than at high N.The double high efficiency(D-HE)type(for both low and high N,the yield is higher)performed well under both high and low N.Apical kernel reacted differently to the N supply.Apical kernel developed well at an early grain filling stage and resulted in a higher kernel number(KN),kernel weight(KW)and GY with better ear characteristics at maturity. 展开更多
关键词 Zea mays L. grain filling nitrogen use efficiency kernel development
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Effect of Phosphorus Fertilization to P Uptake and Dry Matter Accumulation in Soybean with Different P Efficiencies 被引量:12
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作者 AO Xue GUO Xiao-hong +6 位作者 ZHU Qian ZHANG Hui-jun WANG Hai-ying MA Zhao-hui HAN Xiao-ri ZHAO Ming-hui XIE Fu-ti 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第2期326-334,共9页
Phosphorus (P) is an essential element for plant growth and yield. Improving phosphorus use efficiency of crops could potentially reduce the application of chemical fertilizer and alleviate environmental damage. Soy... Phosphorus (P) is an essential element for plant growth and yield. Improving phosphorus use efficiency of crops could potentially reduce the application of chemical fertilizer and alleviate environmental damage. Soybean (Glycine max (L.) Merr.) is sensitive to phosphorus (P) in the whole life history. Soybean cultivars with different P efficiencies were used to study P uptake and dry matter accumulation under different P levels. Under low P conditions, the P contents of leaf in high P efficiency cultivars were greater than those in low P efficiency cultivars at the branching stage. The P accumulation in stems of high P efficiency cultivars and in leaves of low P efficiency cultivars increased with increasing P concentration at the branching stage. At the late podding stage, the P accumulation of seeds in high and low P efficiency cultivars were 22.5 and 26.0%, respectively; and at the mature stage were 69.8 and 74.2%, respectively. In average, the P accumulation in whole plants and each organ was improved by 24.4% in high P efficiency cultivars compared to low P efficiency cultivars. The biomass between high and low P efficiency cultivars were the same under extended P condition, while a significant difference was observed at late pod filling stage. At the pod setting stage, the biomass of high P efficiency cultivars were significant greater (17.4%) than those of low P efficiency cultivars under high P condition. Meanwhile, under optimum growth conditions, there was little difference ofbiomass between the two types of cultivars, however, the P agronomic efficiency and P harvest index were significant higher in high P efficiency cultivars than those in low P efficiency cultivars. 展开更多
关键词 Glycine max (L.) Merr. SOYBEAN phosphorus use efficiency
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Comparison of Copepod Collection Efficiencies by Three Commonly Used Plankton Nets: A Case Study in Bohai Sea, China 被引量:5
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作者 CHEN Hongju YU Hao LIU Guangxing 《Journal of Ocean University of China》 SCIE CAS 2016年第6期1007-1013,共7页
Abstract Selection of net with a suitable mesh size is a key concern in the quantitative assessment of zooplankton, which is cru- cial to understand pelagic ecosystem processes. This study compared the copepod collect... Abstract Selection of net with a suitable mesh size is a key concern in the quantitative assessment of zooplankton, which is cru- cial to understand pelagic ecosystem processes. This study compared the copepod collecting efficiency of three commonly used plankton nets, namely, the China standard coarse net (505 gm mesh), the China standard fine net (77 gin), and the WP-2 net (200 μm) The experiment was performed at six stations in the Bohai Sea during the autumn of 2012. The coarse net substantially un- der-sampled small individuals (body widths 〈 672 gm) and led to the lowest species number in each tow, whereas the fine net col- lected all small copepod species but failed to collect rare species. The WP-2 net appeared to be a compromise of the two other nets, collecting both small copepods and rare species. The abundance of copepods collected by the coarse net (126.4±86.5 indm-3) was one to two orders of magnitude lower than that by the WP-2 net (5802.4 ± 2595.4 indm3), and the value of the fine net (11117.0±4563.41 indm-3) was nearly twice that of the WP-2 net. The abundance of large copepods (i.e., adult Calanus sinicus) in the three nets showed no significant differences, but the abundance of small copepods declined with decreasing mesh size. The dif- ference in abundance resulted from the under-sampling of small copepods with body widths 〈 672 μm and 〈 266μm by the coarse and WP-2 nets, respectively. 展开更多
关键词 plankton net collection efficiency copepod Bohai Sea ABUNDANCE
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Effects of Combined Application of Inorganic Fertilizer and Organic Manures on Nitrogen Use and Recovery Efficiencies of Hybrid Rice (Palethwe-1) 被引量:5
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作者 Kyi Moe Kumudra Win Mg +1 位作者 Kyaw Kyaw Win Takeo Yamakawa 《American Journal of Plant Sciences》 2017年第5期1043-1064,共22页
We conducted two field experiments to investigate combined effects of organic and inorganic fertilizers on nitrogen use and recovery efficiencies of hybrid rice (Palethwe-1) during dry and wet seasons, 2015. Four leve... We conducted two field experiments to investigate combined effects of organic and inorganic fertilizers on nitrogen use and recovery efficiencies of hybrid rice (Palethwe-1) during dry and wet seasons, 2015. Four levels of inorganic fertilizer (0%, 50%, 75%, and 100% NPK), based on recommended rates of 150 kg N ha-1, 70 kg P2O5 ha-1, and 120 kg K2O ha-1, were used with cow manure, poultry manure, and vermicompost (5 t·ha-1each) in a split-plot design with three replicates. In both seasons, with 50% NPK, the N uptake level achieved with poultry manure was similar to that obtained with 75% and 100% NPK. The greatest N use, internal, agronomic N use, and recovery efficiencies were obtained with 50% NPK + poultry manure, but were similar to those obtained from cow manure and vermicompost subplots. As the amount of applied N from organic and inorganic fertilizer increased, the N use efficiency and related parameters decreased, due to similar yields among plots with different NPK application levels. Poultry manure resulted in the highest significant correlations between applied N and N accumulation, followed by cow manure and vermicompost, in both seasons. Neither chemical fertilizer nor organic manure alone led to optimum N use and N recovery efficiencies. The combination of 50% inorganic fertilizer (75 kg N ha-1) and poultry manure (5 t·ha-1) enhanced the N uptake, the N use and recovery efficiencies of hybrid rice. Cow manure (5 t·ha-1) in combination with 75% inorganic fertilizer (112.5 kg N ha-1) was an adequate substitute for reduced chemical fertilizer usage. Therefore, this study highlighted combined application of inorganic fertilizers and organic manures had the benefits not only in reducing the need for chemical fertilizers but also in improving N uptake by hybrid rice (Palethwe-1) leading to the better environment. 展开更多
关键词 NITROGEN Uptake NITROGEN USE EFFICIENCY NITROGEN RECOVERY EFFICIENCY AGRONOMIC NITROGEN USE EFFICIENCY Hybrid Rice
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Car Fuel Economy Simulation Forecast Method Based on CVT Efficiencies Measured from Bench Test 被引量:4
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作者 Yu-Long Lei Yu-Zhe Jia +3 位作者 Yao Fu Ke Liu Ying Zhang Zhen-Jie Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第5期138-153,共16页
Researchers face di culties in studying the e ects of driveline e ciency on car fuel economy via bench and road tests because of long working periods, high costs, and heavy workloads. To simplify the study process and... Researchers face di culties in studying the e ects of driveline e ciency on car fuel economy via bench and road tests because of long working periods, high costs, and heavy workloads. To simplify the study process and shorten test cycles, a car fuel economy simulation forecast method for combining computer simulation forecasting with bench tests is proposed. Taking a continuously variable transmission(CVT) as the research object, a transmission e ?ciency model based on a bench test is constructed. An optimal economic variogram based on the original CVT vari?ogram, the boundary conditions of vehicle performance, the road conditions and the driving behavior of the driver is generated in the Gear Shift Program(GSP)?Generation module in AVL Cruise. And on this basis a driveline simulation model that can calculate the fuel consumption based on the driveline data of a test car is built. The model is used to forecast fuel consumption and calculate real?time CVT e ciency under di erent conditions. Contrastive analyses on simulation results and real car drum test results are made. The largest error between simulation results and drum test results in driving cycles is 4.099%, which is 5.449% under constant velocity condition in driver control mode and 4.2% under constant velocity condition in automatic cruise mode. The results confirm the feasibility of the method and the good performance of the driveline simulation model in accurately forecasting fuel consumption. The method can e ciently investigate the e ects of driveline e ciency on car fuel economy. Moreover, this research provides instruc?tion for accurately forecasting fuel economy as well as references for studies on the e ects of drivelines on car fuel economy. 展开更多
关键词 Fuel economy CVT efficiency Simulation forecast Driveline
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Use of drilling performance to improve rock-breakage efficiencies:A part of mine-to-mill optimization studies in a hard-rock mine 被引量:5
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作者 Junhyeok Park Kwangmin Kim 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2020年第2期179-188,共10页
In a hard-rock mine,blasting is an important rock-breakage process that impacts energy consumption both in downstream comminution processes and mine productivity.Optimizing the blast fragmentation to improve rock-brea... In a hard-rock mine,blasting is an important rock-breakage process that impacts energy consumption both in downstream comminution processes and mine productivity.Optimizing the blast fragmentation to improve rock-breakage efficiencies during crushing and grinding is key to mine-to-mill(MTM)optimization.This study explores the use of monitoring while drilling(MWD)data to achieve this goal.Representative penetration rates(PRs)were extracted from blastholes to estimate intact rock properties and predict the breakage efficiencies that directly affect comminution energy consumption.Two intact rock properties,tensile strength(TS)and Bond work index(BWI),were correlated with the PR data to predict these efficiencies in crushing and grinding,respectively.Because of the complexity of the raw MWD data and effects of various disturbances,the MWD data was preprocessed and normalized to achieve a representative PR value at each blasthole.This preprocessing entailed defining valid PR ranges from the MWD data that could eliminate the noise related to discontinuity features in the rock mass structure as well as errors in operator behaviors.The PR data was also normalized using the adjusted penetration rate(APR)to minimize the effects of mechanical factors such as drill feed force,torque,and rotational speed.To correlate the representative APR value with intact rock properties,TS and BWI,various laboratory experiments were conducted:drilling tests using a high-precision coring machine,Brazilian disc tests,and Bond grindability tests.Based on the results of these experiments,models were developed to predict rock-breakage efficiencies during crushing and grinding based on APR.The result of this study can be used to obtain blast energy designs that consider comminution energy consumption and efficiency in the downstream rock-breakage processes. 展开更多
关键词 Monitoring while drilling(MWD) Mine-to-mill(MTM)optimization Rock-breakage efficiency DRILLING penetration rates
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Comparison of heavy metal removal efficiencies in four activated sludge processes 被引量:3
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作者 杨军 高定 +3 位作者 陈同斌 雷梅 郑国砥 周小勇 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3788-3794,共7页
The removal efficiencies of heavy metals(As, Cr, Cu, Ni, Pb and Zn) were investigated in the 17 operating municipal wastewater treatment plants(WWTPs) and compared with those in four main activated sludge processes. S... The removal efficiencies of heavy metals(As, Cr, Cu, Ni, Pb and Zn) were investigated in the 17 operating municipal wastewater treatment plants(WWTPs) and compared with those in four main activated sludge processes. Significant differences of heavy metal removal efficiencies were observed among four activated sludge processes. The removal efficiency for As(75.5%) in the oxidation ditch(OD) process is significantly higher than that in the conventional activated sludge(CAS) process(38.6%) or sequencing batch reactor(SBR) process(51.4%). The mean removal efficiencies for Cu and Ni in the OD process are 90.5% and 46.7%, respectively, while low mean removal efficiencies are observed for Cu(69.9%) and Ni(16.5%), respectively, in the SBR process. The removal efficiencies for Cu and Ni in the OD process are significantly higher than those in the anaerobic-anoxic-oxic(A2-O) process. These results highlight the differences of removal efficiencies for heavy metals in different processes and should be considered when selecting a wastewater treatment process. 展开更多
关键词 WASTEWATER heavy metal removal efficiency treatment process activated sludge processes
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Leaf area development, dry weight accumulation and solar energy conversion efficiencies of Phaseolus vulgaris L. under different soil moisture levels near Nairobi, Kenya 被引量:2
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作者 M.M.Muniafu J.N.M.Macharia +1 位作者 C.J.Stigter G.L.Coulson 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1999年第4期449-456,共8页
Leaf area development, dry weight accumulation and solar energy conversion efficiencies of Phaseolus vulgaris L. cv GLP\|2 under two soil moisture levels in two contrasting seasons near Nairobi, Kenya were investigate... Leaf area development, dry weight accumulation and solar energy conversion efficiencies of Phaseolus vulgaris L. cv GLP\|2 under two soil moisture levels in two contrasting seasons near Nairobi, Kenya were investigated. The experiment confirms that dry weights and yields of Phaseolus vulgaris are limited by a drought induced decrease in leaf area, leading to less radiation interception as a source for assimilation. However, photosynthetic efficiency in Phaseolus vulgaris also appears to decrease and to contribute to these effects. Finally, an even larger decreases of economic efficiency as obtained in the second season, where stress lasted much later into the season, reveals that such a drought also limits considerably the partitioning and translocation of assimilates to the seeds of Phaseolus vulgaris. The efficiencies obtained are in line with the better literature data for other crops. 展开更多
关键词 economic efficiency Phaseolus vulgaris L. photosynthetic efficiency radiation absorption/interception tube solarimeters
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Selection efficiencies for improving drought/salt tolerances and yield using introgression breeding in rice(Oryza sativa L.) 被引量:2
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作者 Ying Wang Lubiao Zhang +3 位作者 Afif Nafisah Linghua Zhu Jianlong Xu Zhikang Li 《The Crop Journal》 SCIE CAS 2013年第2期134-142,共9页
The backcross(BC) breeding strategy has been increasingly used for developing high yielding varieties with improved abiotic stress tolerances in rice. In this study, 189Huang-Hua-Zhan(HHZ) introgression lines(ILs) dev... The backcross(BC) breeding strategy has been increasingly used for developing high yielding varieties with improved abiotic stress tolerances in rice. In this study, 189Huang-Hua-Zhan(HHZ) introgression lines(ILs) developed from three different selection schemes were evaluated for yield related traits under drought stress and non-stress conditions in the target and off-season winter nursery environments to assess the selection efficiency of BC breeding for improving different complex traits, and led us to five important results. The first result indicated that the primary target traits should be selected first in the target environments(TEs) in order to achieve the maximum genetic gain. Secondly, BC breeding for drought tolerance(DT) in rice was almost equally effective by strong phenotypic selection in the main target environments and in the winter-season of Hainan.Thirdly, exploiting genetic diversity in the subspecific gene pools is of great importance for future genetic improvement of complex traits in rice. Fourthly, considerable genetic gain can be effectively achieved by selection for secondary target traits among the ILs with the primary traits. Finally, the developed ILs provide useful materials for future genetic/genomic dissection and molecular breeding of complex traits. 展开更多
关键词 BACKCROSS BREEDING High YIELD DROUGHT TOLERANCE Salt TOLERANCE SELECTION efficiency
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Operational efficiencies and costs of an arm roll forwarder: A case study at Nasu in Tochigi Prefecture, Japan 被引量:1
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作者 Kazuhiro Aruga Yuto Otsuka +3 位作者 Chikara Nakahata Reiko Yamaguchi Masashi Saito Mayu Nagasaki 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第3期577-583,共7页
We investigated a developed arm roll forwarder at Nasu in Tochigi Prefecture, Japan. An arm roll forwarder can only load a steel container that has been fully loaded with logs beforehand, and can later unload such a c... We investigated a developed arm roll forwarder at Nasu in Tochigi Prefecture, Japan. An arm roll forwarder can only load a steel container that has been fully loaded with logs beforehand, and can later unload such a container. Such a forwarder can shorten the loading and untoading times and improve operational efficiency. We examined two operation systems with an arm roll forwarder and a forwarder. In the first system the loading was done with a grapple-loader. In the second system the loading was done with a processor. The loading times of an arm roll forwarder were significantly tess than those of a forwarder. Because the optimal cycle times (excluding the waiting times for an arm roll for- warder) were significantly reduced, the costs of using an arm roll for- warder are lower, although the loading capacity was small and the hourly operation cost was high. The maximum operational efficiencies varied depending on forwarding distances. The second operation system with an arm roll forwarder exhibited the best operational efficiency within a 1,580-m forwarding distance, and beyond that distance it exhibited the highest operational efficiency when a forwarder was used. Similarly, the cost of operation of the system with an arm roll forwarder was the lowest within a 1,130-m forwarding distance, and beyond that distance the cost was the lowest when using the forwarder. Therefore, the arm roll for- warder is effective within a certain forwarding distance. 展开更多
关键词 arm roll forwarder steel container operational efficiency cost forwarding distance
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Studies on Recovery Efficiencies of Phenols from Phenol Fraction Using Alkali Treatment 被引量:2
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作者 S. Aruna Kumari Goruganthula Venkata Subrahmanya Sarma +2 位作者 G. M. J. Raju J. V. S. Murty C. BhaskaraSarma 《Journal of Chemistry and Chemical Engineering》 2013年第4期334-339,共6页
Experiments were conducted for the extraction of phenols from the phenol fraction obtained from the coal tar distillate. The phenol fraction for the present investigation has been procured from Visakhapatnam Steel Pla... Experiments were conducted for the extraction of phenols from the phenol fraction obtained from the coal tar distillate. The phenol fraction for the present investigation has been procured from Visakhapatnam Steel Plant, Visakhapatnam whose composition is known. The phenol fraction from coal tar distillate can be treated for extracting phenols using caustic soda. An attempt has been made to find out whether the existing practice of using only 8%-15% can be modified by increasing the strength of sodium hydroxide and also explore the possibilities of substituting the sodium hydroxide with KOH as an extractant. The different streams of liquids obtained during experimentation have been analyzed by gas chromatograph. Salient features of the study are that higher concentrations of the alkali significantly improved the separation efficiencies of phenols and also regenerate the phenolate with higher phenol content. Increase in the alkali strength has greatly improved the separation as well as the phenol content in the regenerated phenols. Disposal of effluents containing phenols may lead to environmental problem of ground water pollution and the study throws a light on the removal of phenols from the effluents to the extent possible by using higher strength alkali solutions. 展开更多
关键词 Alkali treatment PHENOL phenol fraction recovery efficiency coal tar.
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Magnesium incorporation efficiencies in Mg_xZn_(1-x)O films on ZnO substrates grown by metalorganic chemical vapor deposition 被引量:1
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作者 胡启昌 丁凯 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第6期465-470,共6页
We investigate the magnesium(Mg) incorporation efficiencies in MgxZn1-xO films on c-plane Zn-face ZnO substrates by using metalorganic chemical vapor deposition(MOCVD) technique. In order to deposit high quality M... We investigate the magnesium(Mg) incorporation efficiencies in MgxZn1-xO films on c-plane Zn-face ZnO substrates by using metalorganic chemical vapor deposition(MOCVD) technique. In order to deposit high quality MgxZn1-xO films,atomically smooth epi-ready surfaces of the hydrothermal grown ZnO substrates are achieved by thermal annealing in O2 atmosphere and characterized by atomic force microscope(AFM). The AFM, scanning electron microscope(SEM),and x-ray diffraction(XRD) studies demonstrate that the MgxZn1-xO films each have flat surface and hexagonal wurtzite structure without phase segregation at up to Mg content of 34.4%. The effects of the growth parameters including substrate temperature, reactor pressure and Ⅵ/Ⅱ ratio on Mg content in the films are investigated by XRD analysis based on Vegard's law, and confirmed by photo-luminescence spectra and x-ray photoelectron spectroscopy as well. It is indicated that high substrate temperature, low reactor pressure, and high Ⅵ/Ⅱratio are good for obtaining high Mg content. 展开更多
关键词 MGXZN1-XO MOCVD incorporation efficiency ZnO bulk crystal
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Water use efficiencies of maize cultivars grown under rain-fed conditions 被引量:2
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作者 Daniel Kwasi Asare Justice Okona Frimpong +1 位作者 Emmanuel Ofori Ayeh Harry Mensah Amoatey 《Agricultural Sciences》 2011年第2期125-130,共6页
Enhancing water use efficiencies of rain-fed maize is a requirement for sustainable maize production, particularly in areas prone to low/drought and erratic rainfall patterns. This study was conducted to assess the re... Enhancing water use efficiencies of rain-fed maize is a requirement for sustainable maize production, particularly in areas prone to low/drought and erratic rainfall patterns. This study was conducted to assess the relationship between total biomass/grain yield and water use efficiencies of three maize cultivars (Golden Crystal, Mamaba and Obatanpa) grown under rain-fed conditions in a coastal savannah agro-ecological environment of Ghana. Results of the study showed that a unified linear model, WUETDM = 0.03TDM with R2 = 0.765 and P ≤ 0.001, described adequately the relation between wa-ter use efficiency and total biomass (dry matter), which is applicable for the three maize cultivars for both the major and minor cropping seasons. A linear model could only, however, describe adequately well the relation between WUEGY and GY for the major (WUEGY = 0.001GY – 0.67;R2 = 0.996;P ≤ 0.001) and minor (WUEGY = 0.002GY + 0.289;R2 = 0.992;P ≤ 0.001) cropping seasons for all the maize cultivars. The linear models developed for the maize cultivars, re-lating WUEGY to GY, are specific to each of the crop growing seasons, indicating that seasonal rainfall impacts significantly on harvest index of the maize cultivars but differently in each of the crop growing seasons as a results of dif-ferences in seasonal rainfall. However, the models could be used to estimate water use efficiencies of each of the three maize cultivars given the appropriate TDM and GY as inputs for the environment under which the study was conducted. 展开更多
关键词 Water Use EFFICIENCY MAIZE CULTIVARS Rain-Fed
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Verification of modified sum-peak method in Monte Carlo simulation of full energy peak and sum-peak efficiencies of a HPGe detector 被引量:1
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作者 Tsukasa Aso Yoshimune Ogata Hidesuke Itadzu 《辐射防护》 CAS CSCD 北大核心 2020年第6期527-532,共6页
The modified sum-peak method estimates radioactivity by using only the peak and the sum-peak count rates.To verify the modified sum-peak method,the dependence of the full energy peak efficiency on the source-to-detect... The modified sum-peak method estimates radioactivity by using only the peak and the sum-peak count rates.To verify the modified sum-peak method,the dependence of the full energy peak efficiency on the source-to-detector distance in a high-purity germanium detector system was studied using a Geant4 Monte Carlo simulation.The effect of the deadlayer in the germanium crystal was estimated by reference to experiments on 241 Am and the relative efficiency of the detector.The peak efficiency dependence on the source-to-detector distance was compared between the simulation and measurements.The modified sum-peak method is discussed with respect to these peak efficiencies. 展开更多
关键词 Geant4 Monte Carlo simulation sum-peak method peak efficiency HPGE 60Co
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Study on the Heavy Metals Removal Efficiencies of Constructed Wetlands with Different Substrates 被引量:1
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作者 Mengzhi CHEN Yingying TANG +1 位作者 Xianpo LI Zhaoxiang YU 《Journal of Water Resource and Protection》 2009年第1期22-28,共7页
In this study constructed wetlands (CWs) were used to remove three heavy metals (Zn, Cu and Pb). The two tested substrates were made of coke and gravel, respectively. First order dynamic model was appropriate to descr... In this study constructed wetlands (CWs) were used to remove three heavy metals (Zn, Cu and Pb). The two tested substrates were made of coke and gravel, respectively. First order dynamic model was appropriate to describe removing of Zn and Cu. The experimental results showed that first dynamic removal rate constants of Zn in CWs with coke and gravel were 0.2326 h-1 and 0.1222 h-1, respectively. And those of Cu in CWs with coke and gravel were 0.2017 h-1 and 0.3739 h-1. However, removal efficiencies of Pb in the coke system and the gravel system were within 95-99%, so the first order dynamic model failed to fit the experimental data because the hydraulic resident times of Pb did not affect outlet concentration of Pb. From the removal rate constants, it is found that the coke and gravel system have different absorption efficiencies of heavy metal pollutants. Therefore, it is suggested that the removal efficiencies of heavy metals are influenced by the choice of substrates to some extent. 展开更多
关键词 SUBSURFACE Flow CONSTRUCTED WETLANDS First Order Dynamic Model Heavy Metal POLLUTANT Substrate Removal Efficiency
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Comparing successful gene knock-in efficiencies of CRISPR/Cas9 with ZFNs and TALENs gene editing systems in bovine and dairy goat fetal fibroblasts 被引量:11
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作者 LIU Hui LIU Chang +5 位作者 ZHAO Yu-hang HAN Xue-jie ZHOU Zheng-wei WANG Chen LI Rong-feng LI Xue-ling 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第2期406-414,共9页
This study aimed to compare the efficiencies of clustered regulatory interspaced short palindromic repeat(CRISPR)/Cas9-mediated gene knock-ins with zinc finger nucleases(ZFNs) and transcription activator-like effe... This study aimed to compare the efficiencies of clustered regulatory interspaced short palindromic repeat(CRISPR)/Cas9-mediated gene knock-ins with zinc finger nucleases(ZFNs) and transcription activator-like effector nucleases(TALENs) in bovine and dairy goat fetal fibroblasts. To test the knock-in efficiency, a set of ZFNs and CRISPR/Cas9 plasmids were designed to edit the bovine myostatin(MSTN) gene at exon 2, while a set of TALENs and CRISPR/Cas9 plasmids were designed for editing the dairy goat β-casein gene at exon 2. Donor plasmids utilizing the ZFNs, TALENs, and CRISPR/Cas9 cutting sites were constructed in theGFP-PGK-Neo R plasmid background, including a 5′ and 3′ homologous arm flanking the genes humanized Fat-1(h Fat-1) or enhanced green fluorescent protein(eGFP). Subsequently, the ZFNs, TALENs, or CRISPR/Cas9 and thehFat-1 or eGFP plasmids were co-transfected by electroporation into bovine and dairy goat fetal fibroblasts. After G418(Geneticin) selection, single cells were obtained by mouth pipetting, flow cytometry or a cell shove. The gene knock-in events were screened by PCR across the homologous arms. The results showed that in bovine fetal fibrobalsts, the efficiencies of ZFNs-mediated eGFP andhFat-1 gene knock-ins were 13.68 and 0%, respectively. The efficiencies of CRISPR/Cas9-mediated eGFP andhFat-1 gene knock-ins were 77.02 and 79.01%, respectively. The eGFP gene knock-in efficiency using CRISPR/Cas9 was about 5.6 times higher than when using the ZFNs gene editing system. Additionally, thehFat-1 gene knock-in was only obtained when using the CRISPR/Cas9 system. The difference of knockin efficiencies between the ZFNs and CRISPR/Cas9 systems were extremely significant(P〈0.01). In the dairy goat fetal fibroblasts, the efficiencies of TALENs-mediated eGFP andhFat-1 gene knock-ins were 32.35 and 26.47%, respectively. Theefficiencies of eGFP and hFat-1 gene knock-ins using CRISPR/Cas9 were 70.37 and 74.29%, respectively. The knock-in efficiencies difference between the TALENs and CRISPR/Cas9 systems were extremely significant(P〈0.01). This study demonstrated that CRISPR/Cas9 was more efficient at gene knock-ins in domesticated animal cells than ZFNs and TALENs. The CRISPR/Cas9 technology offers a new era of precise gene editing in domesticated animal cell lines. 展开更多
关键词 myostatin(MSTN) β-casein(CSN2) bovine fetal fibroblasts CRISPR/Cas9 dairy goat fetal fibroblasts eGFP hFat-1 knock-in mutation efficiency TALENs ZFNs
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