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An integrated technology for the absorption and utilization of CO_(2)in alkanolamine solution for the preparation of BaCO_(3)in a high-gravity environment
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作者 Kangrui Nie Ruize Shang +3 位作者 Fuming Miao Liuxiang Wang Youzhi Liu Weizhou Jiao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期117-125,共9页
In this study,an integrated technology is proposed for the absorption and utilization of CO_(2)in alkanolamine solution for the preparation of BaCO_(3)in a high-gravity environment.The effects of absorbent type,high-g... In this study,an integrated technology is proposed for the absorption and utilization of CO_(2)in alkanolamine solution for the preparation of BaCO_(3)in a high-gravity environment.The effects of absorbent type,high-gravity factor,gas/liquid ratio,and initial BaCl2concentration on the absorption rate and amount of CO_(2)and the preparation of BaCO_(3)are investigated.The results reveal that the absorption rate and amount of CO_(2)follow the order of ethyl alkanolamine(MEA)>diethanol amine(DEA)>N-methyldiethanolamine(MDEA),and thus MEA is the most effective absorbent for CO_(2)absorption.The absorption rate and amount of CO_(2)under high gravity are higher than that under normal gravity.Notably,the absorption rate at 75 min under high gravity is approximately 2 times that under normal gravity.This is because the centrifugal force resulting from the high-speed rotation of the packing can greatly increase gas-liquid mass transfer and micromixing.The particle size of BaCO_(3)prepared in the rotating packed bed is in the range of 57.2—89 nm,which is much smaller than that prepared in the bubbling reactor(>100.3 nm),and it also has higher purity(99.6%)and larger specific surface area(14.119 m^(2)·g^(-1)).It is concluded that the high-gravity technology has the potential to increase the absorption and utilization of CO_(2)in alkanolamine solution for the preparation of BaCO_(3).This study provides new insights into carbon emissions reduction and carbon utilization. 展开更多
关键词 High-gravity technology Wet absorption CO_(2)capture Enhanced mass transfer CO_(2)utilization Barium carbonate
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Differences in Phosphorus Absorption and Utilization Efficiency of Soybean in Mature Period under Phosphorus Stress
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作者 Yanli ZHANG Hongling QI +2 位作者 Fengxia LU Ming HAN Panpan WANG 《Agricultural Biotechnology》 CAS 2014年第6期24-27,30,共5页
In this study, four phosphorus-inefficient soybean genotypes (1903, 1305, D17 and D18) and four phosphorus-efficient soybean genotypes (D31, D34, D37 and D38 ) were selected as experimental materials for soil cult... In this study, four phosphorus-inefficient soybean genotypes (1903, 1305, D17 and D18) and four phosphorus-efficient soybean genotypes (D31, D34, D37 and D38 ) were selected as experimental materials for soil culture experiment under high and low phosphorus treatments, to investigate the grain yield, phosphorus content, phosphorus uptake and the relationship between phosphorus utilization efficiency and phosphorus efficiency of soybean genotypes with different phos- phorus efficiency in mature period. According to the experimental results, under low phosphorus treatment, four phosphorus-efficient soybean genotypes exhibited significantly high phosphorus uptake in mature period, especially for D31 and D37; however, three phosphorus-efficient genotypes showed no advantages in adapta- bility of phosphorus utilization efficiency, while only I)31 exhibited high phosphorus utilization and absorption capacity. Correlation analysis and path analysis showed that phosphorus deficiency of soybean was mainly detemained by phosphorus absorption capacity, and phosphorus deficiency under (-P) treatment was sig- nificandy higher than ( + P) treatment. Phosphorus uptake and phosphorus utilization efficiency posed great direct effects on phosphorus efficiency, and phosphorus uptake exhibited a greater contribution ; in addition, these two factors both posed small indirect effects. In mature period at reproductive growth stage, phosphorus absorption efficiency (phosphorus uptake) was the main variation source of phosphorus efficiency of various soybean genotypes in mature period. Therefore, strong phosphorus uptake and accumulation capacity of phosphorus-efficient soybean genotypes in mature period is an important nutrition foundation for the information of high grain yield. 展开更多
关键词 SOYBEAN Low phosphorus stress Phosphorus efficiency absorption efficiency utilization efficiency
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Recycling and utilization of coal gasification residues for fabricating Fe/C composites as novel microwave absorbents 被引量:1
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作者 Guomin Li Xiaojie Xue +7 位作者 Lutao Mao Yake Wang Lingxiao Li Guizhen Wang Kewei Zhang Rong Zhang Yuexiang Wang Liping Liang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第3期591-599,共9页
Under the background of a transformation of the global energy structure,coal gasification technology has a wide application prospect,but its by-product,the coal gasification residue(CGR),is still not being efficiently... Under the background of a transformation of the global energy structure,coal gasification technology has a wide application prospect,but its by-product,the coal gasification residue(CGR),is still not being efficiently utilized for recycling.The CGR contains abundant carbon components,which could be applied to the microwave absorption field as the carbon matrix.In this study,Fe/CGR composites are fabricated via a two-step method,including the impregnation of Fe^(3+)and the reduction process.The influence of the different loading capacities of the Fe component on the morphology and electromagnetic properties is studied.Moreover,the loading content of Fe and the surface morphology of the Fe/CGR can be reasonably controlled by adjusting the concentration of the ferric nitrate solution.Meanwhile,Fe particles are evenly inserted on the CGR framework,which expands the Fe/CGR interfaces to enhance interfacial polarization,thus further improving the microwave-absorbing(MA)properties of composites.Particularly,as the Fe^(3+)concentration is 1.0 mol/L,the Fe/CGR composite exhibits outstanding performance.The reflection loss reaches-39.3 dB at 2.5 mm,and the absorption bandwidth covers 4.1 GHz at 1.5 mm.In this study,facile processability,resource recycling,appropriately matched impedance,and excellent MA performance are achieved.Finally,the Fe/CGR composites not only enhance the recycling of the CGR but also pioneer a new path for the synthesis of excellent absorbents. 展开更多
关键词 coal gasification residue recycling utilization COMPOSITE microwave absorption
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Differences in the Efficiency of Potassium(K) Uptake and Use in Five Apple Rootstock Genotypes 被引量:4
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作者 CHANG Cong LI Chao +3 位作者 LI Cui-ying KANG Xiao-yu ZOU Yang-jun MA Feng-wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第9期1934-1942,共9页
Plants that grow well while accumulating and transporting less potassium(K) perform better than more-sensitive plants when under deficiency conditions, which makes low-K-input and environmentally friendly agricultur... Plants that grow well while accumulating and transporting less potassium(K) perform better than more-sensitive plants when under deficiency conditions, which makes low-K-input and environmentally friendly agriculture possible. We conducted hydroponics and sand culture experiments to evaluate the efficiency of various apple(Malus domestica Borkh) rootstocks in their K uptake and utilization. Five genotypes were selected which are widely used in China- M. hupehensis Rehd, M. prunifolia Borkh, M. robusta Rehd, M. sieversii Roem, and M. rockii Rehd. Plant heights, root and shoot dry weights, and K concentrations were recorded. These genotypes differed markedly in dry weights, absolute and relative K concentrations, absolute and relative K accumulations, and their K efficiency ratio under deficient K conditions. The last parameter, expressed as relative shoot dry weight, was strongly and positively correlated with the other four parameters in each genotype. Therefore, we suggest that this parameter could serve as an index when selecting K-efficient genotypes. In this study, we have determined that M. sieversiiand M. rockii are K-inefficient genotypes; M. prunifolia is K-efficient genotype; M. hupehensis and M. robusta have moderate levels of potassium efficiency. 展开更多
关键词 apple rootstock genotypes potassium efficiency genotype difference potassium uptake potassium utilization
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Effects of Organic Selenium on Growth Properties, Selenium Absorption and Utilization, Antioxidant Activity and Immunity in Weaning Piglets 被引量:2
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作者 Weixian Zhang Yong Li +4 位作者 Hongyu Deng Zheng Li Ruiping Xiang Jianlai Guo Chunmei Pan 《Food and Nutrition Sciences》 2020年第5期385-395,共11页
This experiment was conducted to determine the influences of adding organic selenium (Se) on growth properties, Se absorption and utilization, immunity and antioxidant activity in diets of Duroc weaning piglets. This ... This experiment was conducted to determine the influences of adding organic selenium (Se) on growth properties, Se absorption and utilization, immunity and antioxidant activity in diets of Duroc weaning piglets. This study was performed on 36 (average weight 7.6 kg) weaning piglets. The weaning piglets were randomly allocated to 1 of 4 homogeneous treatments (A, control treatment, no added Se;B, Sodium selenite, 0.3 mg Se/kg feed;C, yeast Se, 0.3 mg Se/kg;D, DL-methionine Se 0.3 mg Se/kg). Every treatment had 3 replicates, every replicate had 3 piglets. The experiment lasted for 35 d, with the first 7 d for adaptation. Feed intake, residual and contaminated feed were recorded every day. Every piglet weight was weighted respectively at beginning and end of experiment. Daily intake, gain weight and feed conversion rates of every replicate were calculated finally. Se concentrations of serum, blood antioxidant and immunity index were analyzed in the 36th d of experiment. The results showed average daily gain of treatment C was significant higher (P 0.05) and D had higher trend than that of treatment A and B (P = 0.06) respectively. And feed and gain ratio of C and D had trends to lower than them of A and B (P = 0.14). However, all the intake of every week and whole period had no significant differences among treatments (P > 0.05). At same time, except for the Immunoglobulin M of treatment D and C was higher than that of treatment A and B significantly (P < 0.05), all the other Se contents of serum, immunity indexes, blood cell parameters and enzymatic activities had no significant differences among treatments (P > 0.05). But they took on some obvious trends. For example, the Se contents and glutathione peroxidase activities increased successively in order of treatment A, B, C and D;the blood urea nitrogen and total bilirubin of treatment A had higher trend than that of other treatments (P = 0.06). All in all, adding to organic Se in basal diets could improve the animal’s healthy levels, growth properties and Se utilization to some extent. Relatively speaking, the DL-methionine Se had more advantages compared to yeast Se. 展开更多
关键词 Se absorption and utilization GROWTH Properties Antioxidant Activity and IMMUNITY WEANING PIGLETS
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Computational Analysis of the Effect of Nano Particle Material Motion on Mixed Convection Flow in the Presence of Heat Generation and Absorption 被引量:2
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作者 Muhammad Ashraf Amir Abbas +3 位作者 Saqib Zia Yu-Ming Chu Ilyas Khan Kottakkaran Sooppy Nisar 《Computers, Materials & Continua》 SCIE EI 2020年第11期1809-1823,共15页
The present study is concerned with the physical behavior of the combined effect of nano particle material motion and heat generation/absorption due to the effect of different parameters involved in prescribed flow mo... The present study is concerned with the physical behavior of the combined effect of nano particle material motion and heat generation/absorption due to the effect of different parameters involved in prescribed flow model.The formulation of the flow model is based on basic universal equations of conservation of momentum,energy and mass.The prescribed flow model is converted to non-dimensional form by using suitable scaling.The obtained transformed equations are solved numerically by using finite difference scheme.For the analysis of above said behavior the computed numerical data for fluid velocity,temperature profile,and mass concentration for several constraints that is mixed convection parameterλt,modified mixed convection parameterλc,Prandtl number Pr,heat generation/absorption parameterδ,Schmidt number Sc,thermophoresis parameter Nt,and thermophoretic coefficient k are sketched in graphical form.Numerical results for skin friction,heat transfer rate and the mass transfer rate are tabulated for various emerging physical parameters.It is reported that in enhancement in heat,generation boosts up the fluid temperature at some positions of the surface of the sphere.As heat absorption parameter is decreased temperature field increases at position X=π/4 on the other hand,no alteration at other considered circumferential positions is noticed. 展开更多
关键词 Nano material mixed convection finite difference method heat generation/absorption SPHERES
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THE RELATIONSHIP BETWEEN THE EM ENERGY ABSORPTION OF HUMAN BODY AND THE INCIDENT DIRECTION AND POLARIZATION OF PLANE WAVE
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作者 王长清 祝西里 《Journal of Electronics(China)》 1993年第1期79-85,共7页
The problems of EM energy absorption of human body irradiated by plane wave arediscussed by the Finite-Difference Time-Domain(FD-TD)method.The local Specific AbsorptionRates(SARs),the whole-body average SARs and the l... The problems of EM energy absorption of human body irradiated by plane wave arediscussed by the Finite-Difference Time-Domain(FD-TD)method.The local Specific AbsorptionRates(SARs),the whole-body average SARs and the layer average SARs for the inhomogeneousblock model of human body with different incident direction and different polarization of theincident waves are calculated.The results show that the appearance of maximum EM energyabsorption is not always at the situation of the front incidence and the local SARs are moreimportant for the interaction of the EM fields with human body.All results provide more infor-mation about the electromagnetic dosimetry for human body. 展开更多
关键词 EM energy absorption FINITE-DIFFERENCE TIME-DOMAIN method Specific absorption rate Electromangetic DOSIMETRY
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Enhanced light absorption of silicon in the near-infrared band by designed gold nanostructures
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作者 刘菊 钟晓岚 李志远 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第4期551-556,共6页
A scheme to enhance near-infrared band absorption of a Si nanoparticle by placing the Si nanoparticle into a designed gold nanostructure is proposed. Three-dimensional (3D) finite-difference time-domain simulations ... A scheme to enhance near-infrared band absorption of a Si nanoparticle by placing the Si nanoparticle into a designed gold nanostructure is proposed. Three-dimensional (3D) finite-difference time-domain simulations are employed to calcu- late the absorption spectrum of the Si nanostructure and maximize it by generating alternate designs. The results show that in the near-infrared region over 700 nm, the absorption of a pure Si nanoparticle is very low, but when the same nanoparticle is placed within an optimally designed gold nanostructure, its absorption cross section can be enhanced by more than two orders of magnitude in the near-infrared band. 展开更多
关键词 surface plasmon resonance NEAR-INFRARED silicon absorption finite-difference time-domain opti-mization
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Technical Perspective of Carbon Capture,Utilization,and Storage 被引量:14
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作者 Qingyang Lin Xiao Zhang +2 位作者 Tao Wang Chenghang Zheng Xiang Gao 《Engineering》 SCIE EI CAS 2022年第7期27-32,共6页
Carbon dioxide(CO_(2))is the primary greenhouse gas contributing to anthropogenic climate change which is associated with human activities.The majority of CO_(2) emissions are results of the burning of fossil fuels fo... Carbon dioxide(CO_(2))is the primary greenhouse gas contributing to anthropogenic climate change which is associated with human activities.The majority of CO_(2) emissions are results of the burning of fossil fuels for energy,as well as industrial processes such as steel and cement production.Carbon capture,utilization,and storage(CCUS)is a sustainable technology promising in terms of reducing CO_(2) emissions that would otherwise contribute to climate change.From this perspective,the discussion on carbon capture focuses on chemical absorption technology,primarily due to its commercialization potential.The CO_(2) absorptive capacity and absorption rate of various chemical solvents have been summarized.The carbon utilization focuses on electrochemical conversion routes converting CO_(2) into potentially valuable chemicals which have received particular attention in recent years.The Faradaic conversion efficiencies for various CO_(2) reduction products are used to describe efficiency improvements.For carbon storage,successful deployment relies on a better understanding of fluid mechanics,geomechanics,and reactive transport,which are discussed in details. 展开更多
关键词 CCUS Carbon capture Carbon utilization Carbon storage Chemical absorption Electrochemical conversion Storage mechanism
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Xylose: absorption, fermentation, and post-absorptive metabolism in the pig 被引量:3
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作者 Nichole F.Huntley John F.Patience 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2018年第1期1-9,共9页
Xylose, as β-1,4-linked xylan, makes up much of the hemicel ulose in cel wal s of cereal carbohydrates fed to pigs. As inclusion of fibrous ingredients in swine diets continues to increase, supplementation of carbohy... Xylose, as β-1,4-linked xylan, makes up much of the hemicel ulose in cel wal s of cereal carbohydrates fed to pigs. As inclusion of fibrous ingredients in swine diets continues to increase, supplementation of carbohydrases, such as xylanase,is of interest. However, much progress is warranted to achieve consistent enzyme efficacy, including an improved understanding of the utilization and energetic contribution of xylanase hydrolysis product(i.e. xylooligosaccharides or monomeric xylose). This review examines reports on xylose absorption and metabolism in the pig and identifies gaps in this knowledge that are essential to understanding the value of carbohydrase hydrolysis products in the nutrition of the pig. Xylose research in pigs was first reported in 1954, with only sporadic contributions since. Therefore, this review also discusses relevant xylose research in other monogastric species, including humans. In both pigs and poultry, increasing purified D-xylose inclusion general y results in linear decreases in performance, efficiency, and diet digestibility. However,supplementation levels studied thus far have ranged from 5% to 40%, while theoretical xylose release due to xylanase supplementation would be less than 4%. More than 95% of ingested D-xylose disappears before the terminal ileum but mechanisms of absorption have yet to be ful y elucidated. Some data support the hypothesis that mechanisms exist to handle low xylose concentrations but become overwhelmed as luminal concentrations increase. Very little is known about xylose metabolic utilization in vertebrates but it is wel recognized that a large proportion of dietary xylose appears in the urine and significantly decreases the metabolizable energy available from the diet. Nevertheless, evidence of labeled D-xylose-1-^(14)C appearing as expired^(14)CO_2 in both humans and guinea pigs suggests that there is potential,although small, for xylose oxidation. It is yet to be determined if pigs develop increased xylose metabolic capacity with increased adaptation time to diets supplemented with xylose or xylanase. Overall, xylose appears to be poorly utilized by the pig, but it is important to consider that only one study has been reported which supplemented D-xylose dietary concentrations lower than 5%. Thus, more comprehensive studies testing xylose metabolic effects at dietary concentrations more relevant to swine nutrition are warranted. 展开更多
关键词 Pentose utilization SWINE Threitol Xylose absorption Xylose metabolism
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Genotypic Variations in Potassium Absorption and Utilization by Amaranthus spp. 被引量:5
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作者 TUSHUXIN SUNJINGHE 《Pedosphere》 SCIE CAS CSCD 2000年第4期363-372,共10页
The kinetics of K+ absorption and the utilization of both applied K and K in a calcareous alluvisol with low available K by different genotypes of grain amaranth (Amaranthus spp.), an ancient pseudo-cereal that produc... The kinetics of K+ absorption and the utilization of both applied K and K in a calcareous alluvisol with low available K by different genotypes of grain amaranth (Amaranthus spp.), an ancient pseudo-cereal that produces a large biomass and a rich source of healthy nutrients and mineral elements, were studied by means of ion depletion technique and pot experiments. Grain amaranth had a high affinity for K+ uptake in comparison with corn and cotton. However, there were differences among Amaranthus spp. in K absorption and utilization. Some cultivars such as R104, CX-4, Du001, Hy015 and Hr029 which had a higher rate of K absorption and stronger affinity for K+ were typical varieties with high K-use efficiency (KUE). The results showed that high KUE cultivars grew quickly, possessed stronger ability to take up soil slowly available K and mineral K, and did not respond to K fertilization in the soil with low available K. Correspondingly, grain amaranth cultivars CX-77, Cr024, Vd001, Re003 and Sn003 were relatively low in KUE. Compared with high KUE cultivars, they took up more soil available K and both of their dry matter accumulation and K uptake responded to K applied significantly. 展开更多
关键词 grain amaranth KINETICS potassium absorption and utilization
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FDTD Simulation of Three Photon Absorption and Realization of NAND Gate with GaAs Wire Waveguide
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作者 Ivy Dutta Anirban Roy Chowdhury Dharmadas Kumbhakar 《Optics and Photonics Journal》 2013年第5期311-317,共7页
GaAs has high three photon absorption (3PA) co-efficient at mid-infrared wavelength like2.2mm and waveguides can be formed with this material like silicon nano-wires. It is shown that three-photon-absorption in GaAs w... GaAs has high three photon absorption (3PA) co-efficient at mid-infrared wavelength like2.2mm and waveguides can be formed with this material like silicon nano-wires. It is shown that three-photon-absorption in GaAs wire waveguide can be utilized to form NAND gate. Three-photon-absorption is incorporated in one-dimensional Finite Difference Time Domain (FDTD) equations. The evolution of a probe pulse under the influence of a pump pulse through crossabsorption in a waveguide is investigated using FDTD simulation, where the dominant process is nonlinear three-photon-absorption. Output probe power dependence on input pump power shows that GaAs waveguide NAND gate has higher extinction ratio in comparison to NAND gate using two-photon-absorption in silicon waveguide. 展开更多
关键词 Three PHOTON absorption FIFTH Order NONLINEARITY FDTD Full Vector Finite Difference Method PUMP BEAM and Probe BEAM
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A Brief Analysis of the Key Points to Avoid Misunderstanding and Inappropriate Language Expressions in Business Communication
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作者 宋旭 《海外英语》 2018年第2期235-237,239,共4页
Opportunities for business cooperation have been increased dramatically in the new environment, and under such circumstance, language usage in business communication places a significant role, particularly in oral bus... Opportunities for business cooperation have been increased dramatically in the new environment, and under such circumstance, language usage in business communication places a significant role, particularly in oral business language. To promote harmonious conversations, certain factors and manners of communication like paying attention to the cultural differences, the proper use of humor, mutual understanding, and the avoidance of misunderstanding ambiguity should be taken into consideration to avoid an unsuccessful result. 展开更多
关键词 business communication proper language expression cultural differences avoidance of misunderstanding and ambiguity less utilization of negative words
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Effects of tridimensional uniform sowing on water consumption, nitrogen use, and yield in winter wheat 被引量:9
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作者 Zhiqiang Tao Shaokang Ma +5 位作者 Xuhong Chang Demei Wang Yanjie Wang Yushuang Yang Guangcai Zhao Jiancang Yang 《The Crop Journal》 SCIE CAS CSCD 2019年第4期480-493,共14页
Wheat is a staple crop worldwide, but yields may diminish as climate change causes increasingly unpredictable patterns of precipitation and soil nutrient availability. Farmers are thus challenged to maximize planting ... Wheat is a staple crop worldwide, but yields may diminish as climate change causes increasingly unpredictable patterns of precipitation and soil nutrient availability. Farmers are thus challenged to maximize planting efficiency to increase yield, while also improving their resource use efficiency. In this study the effectiveness of tridimensional uniform sowing was tested across a range of planting densities for winter wheat crops on the North China Plain. Tridimensional uniform sowing was tested against conventional drilling at three planting densities (180 × 104, 270 × 104, and 360 × 104 plants ha 1) and assessed for water consumption, biomass, nitrogen uptake and allocation, and aspects of yield. The tridimensional uniform sowing treatment outperformed the conventional drilling treatment in most metrics and at most planting densities, while performing markedly better at higher planting densities. Water consumption decreased and nitrogen efficiency increased. Tiller number and percentage of productive tillers, leaf area index, dry weight, and yield increased without a significant decline in grain protein. Nitrogen allocation was more efficient under tridimensional uniform sowing than with conventional drilling, and also varied according to annual precipitation and planting density. Both yield and grain protein contents were significantly correlated with the amount of pre-anthesis accumu- lated nitrogen translocated from vegetative organs to kernels after anthesis. Overall, a density of 270 × 104 plants ha 1 provided the highest water use efficiency and grain yield. Tridimensional uniform sowing will benefit farmers by forming stronger overall crops, promoting the coordinated improvement of yield, nitrogen uptake and efficiency, and increasing grain protein content at higher planting densities. 展开更多
关键词 WINTER wheat SOWING pattern NITROGEN absorption and utilization YIELD GRAIN protein content
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Comparisons and optimization of two absorption chiller types by considering heat transfer area,exergy and economy as single-objective functions
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作者 Yida Qiu Jingkun Wang +3 位作者 Jing Han Yuzhu Chen Jun Wang Peter D.Lund 《Clean Energy》 EI CSCD 2024年第1期55-65,共11页
Absorption cooling technology is an environmentally friendly method to generate continuous chilled water making use of multiple thermal sources,such as waste heat and renewable thermal energy.In this study,two absorpt... Absorption cooling technology is an environmentally friendly method to generate continuous chilled water making use of multiple thermal sources,such as waste heat and renewable thermal energy.In this study,two absorption chillers(nominal capacity of 400 kW)with series and parallel connections are evaluated.To research the ideal configuration of chillers after thermodynamic analysis,the structures of the chillers are optimized using the particle swarm optimization algorithm by considering the heat transfer area(HTA),exergy efficiency and total annual cost as single-objective functions.The impact of temperature differences between external and internal flows,heat exchanger efficiencies and the solution allocation ratio is estimated.The optimized HTA,coefficient of perform-ance,exergy efficiency and total annual cost are 149.0 m^(2),1.56,29.44%and$229119 for the series-connected chiller,and 146.7 m^(2),1.59,31.45%and$234562 for the parallel-connected type,respectively.Under the lowest HTA condition,compared with the reference simulation results,the energy and exergy performances are improved,while the annual total cost is higher.The annual total cost is highest when maximizing the exergy efficiency,which is attributed to the increase in the HTA.The operating cost accounts for 27.42%(series type)and 26.54%(parallel type)when the annual cost is the lowest. 展开更多
关键词 absorption chiller series/parallel-connected temperature difference parameters solution allocation ratio
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Methods on Identification and Screening of Rice Genotypes with High Nitrogen Efficiency 被引量:6
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作者 CHENG Jian-feng JIANG Han-yan +2 位作者 LIU Yi-bai DAI Ting-bo CAO Wei-xing 《Rice science》 SCIE 2011年第2期127-135,共9页
In order to establish methods for indentification and screening of rice genotypes with high nitrogen (N) efficiency, N absorption efficiency (NAE), N utilization efficiency (NUE) and N harvest index (NHI) in t... In order to establish methods for indentification and screening of rice genotypes with high nitrogen (N) efficiency, N absorption efficiency (NAE), N utilization efficiency (NUE) and N harvest index (NHI) in ten rice genotypes were investgated at the elongation, booting, heading and maturity stages under six N levels in a pot experiment with soil-sand mixtures at various ratios. NAE in various rice genotypes firstly increased, peaked under a medium nitrogen rate of 0.177 g/kg and then decreased, but NUE and NHI always decreased with increasing nitrogen levels. NAE in various rice genotypes ever increased with growing process and NUE indicated a descending tendency of elongation stage〉heading stage〉maturity stage〉booting stage. N level influenced rice NAE, NUE and NHI most, followed by genotype, and the both effects were significant at 0.01 level. In addition, the interaction effects of genotype and nitrogen level on rice NAE and NUE were significant at 0.01 level, but not significant on rice NHI. Because the maximum differences of NAE and NUE were found at the elongation stage, it was thought to be the most suitable stage for identification and screening these two paremeters. Therefore, the optimum conditions for identification and screening of rice NAE, NUE and NHI in a pot experiment were the nitrogen rate of 0.157 g/kg at the elongation stage, low nitrogen at the elongation stage, and the nitrogen rate of 0.277 g/kg at the maturity stage, respectively. 展开更多
关键词 rice GENOTYPE IDENTIFICATION SCREENING high nitrogen efficiency nitrogen absorption efficiency nitrogen utilization efficiency nitrogen harvest index
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东道国禀赋、本地创新与OFDI逆向技术溢出效应 被引量:3
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作者 宋瑛 杨露 王亚飞 《西部论坛》 CSSCI 北大核心 2023年第1期94-107,共14页
利用对外直接投资(OFDI)形成的逆向技术溢出推动国内经济高质量发展是实现国内国际双循环相互促进的重要路径。以30个省份为样本地区、45个“一带一路”沿线国家为样本东道国,采用2008—2020年面板数据,分析OFDI逆向技术溢出对地区制造... 利用对外直接投资(OFDI)形成的逆向技术溢出推动国内经济高质量发展是实现国内国际双循环相互促进的重要路径。以30个省份为样本地区、45个“一带一路”沿线国家为样本东道国,采用2008—2020年面板数据,分析OFDI逆向技术溢出对地区制造业全要素生产率(GTFP)的影响,并从技术差距、技术差异和技术吸收能力角度探讨OFDI逆向技术溢出效应的产生机制和异质性表现,结果发现:OFDI逆向技术溢出的增加可以显著促进地区制造业GTFP(包括绿色技术进步和绿色技术效率)提升;相比对自然资源充裕型东道国OFDI,对技术充裕型东道国OFDI能够产生更强的逆向技术溢出效应,但对市场充裕型东道国OFDI的逆向技术溢出与地区制造业GTFP负相关;OFDI逆向技术溢出效应在东、中、西部地区表现出依次增强的趋势,表明技术差距的缩小会减弱OFDI逆向技术溢出效应;高新技术行业的OFDI逆向技术溢出效应显著,而传统行业的OFDI逆向技术溢出效应不显著,表明技术差异的扩大会增强OFDI逆向技术溢出效应;地区研发强度和创新能力对OFDI逆向技术溢出效应具有正向调节作用,表明本地技术吸收能力增强可以强化OFDI逆向技术溢出效应。因此,应采取差异化的国际投资策略以更好地利用OFDI逆向技术溢出效应来促进高质量发展。 展开更多
关键词 对外直接投资 逆向技术溢出效应 要素禀赋 技术差距 技术差异 技术吸收能力
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USE OF FINITE-DIFFERENCE TIME-DOMAIN METHOD FOR CALCULATING EM ABSORPTION IN LOSSY DIELECTRIC SCATTERER
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作者 王长清 陈金元 《Journal of Electronics(China)》 1991年第4期357-362,共6页
The problem for calculating EM energy absorption by lossy dielectric scatterer ir-radiated by plane wave are discussed.The factors affecting the accuracy of computation arediscussed.The calculated results of EM energy... The problem for calculating EM energy absorption by lossy dielectric scatterer ir-radiated by plane wave are discussed.The factors affecting the accuracy of computation arediscussed.The calculated results of EM energy absorption and its distribution in homogeneousand layered homogenous lossy dielectric spheres are presented,and a comparison of these resultswith analytical solution is given.The calculation is carried out for dielectric cylinder on conduct-ing ground as well,and the results are compared with the image theory.All the computationsshew that the finite-difference time-domain method can give satisfactory results. 展开更多
关键词 LOSSY DIELECTRIC SCATTERER Electromagnetic absorption FINITE-DIFFERENCE timedomain method
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Thermodynamics of Cascaded Waste Heat Utilization from Flue Gas and Circulating Cooling Water
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作者 LI Yuanyuan CHEN Xin +1 位作者 JIANG Shan LU Gui 《Journal of Thermal Science》 SCIE EI CAS CSCD 2023年第6期2166-2178,共13页
A detailed thermal power plant model was developed to evaluate power plant waste heat usage in terms of the operating parameters,energy consumption,water consumption,and pollutant emissions.This model was used to anal... A detailed thermal power plant model was developed to evaluate power plant waste heat usage in terms of the operating parameters,energy consumption,water consumption,and pollutant emissions.This model was used to analyze the bypass flue gas energy cascade utilization design which provides excellent energy savings and emission reductions.This paper then presents a design to use the low-temperature waste heat and to extract water from the flue gas.The low-grade heat can be recovered from a coal-fired unit using absorption heat pumps to increase the air preheating.This method significantly reduces the turbine steam extraction in the low pressure stages which increases the turbine power and reduces the coal consumption.This design has a small heat transfer temperature difference between the air preheater and the air warmer,resulting in a smaller exergy loss.The power output of the present design was 1024.28 MW with a coal consumption savings of 3.69 g·(kWh)^(−1).In addition,the present design extracts moisture out of the flue gas to produce 46.48 t·h^(−1)of water.The main goal of this work is to provide a theoretical analysis for studying complex thermal power plant systems and various energy conservation and CO_(2)reduction options for conventional power plants. 展开更多
关键词 integrated thermal power plant model low-grade waste heat energy cascade utilization exergy losses absorption heat pumps
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过去20年城乡高中生的教育效用与教育志向:基于三个出生队列的历史比较研究 被引量:3
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作者 张良 张文新 《心理学报》 CSSCI CSCD 北大核心 2024年第7期926-937,共12页
本研究采用时间滞后设计,考察过去20年我国高中生教育效用和教育志向水平的年代和城乡差异,以及二者与个体学业成绩、父母学历之间关系的年代和城乡差异。分别在1999年、2010年、2018年对来自相同的三个地区(包括城市和农村)、相同学校... 本研究采用时间滞后设计,考察过去20年我国高中生教育效用和教育志向水平的年代和城乡差异,以及二者与个体学业成绩、父母学历之间关系的年代和城乡差异。分别在1999年、2010年、2018年对来自相同的三个地区(包括城市和农村)、相同学校的高中生进行问卷调查,使用协方差分析和回归分析进行数据分析。结果发现:(1)自1999年至2018年,城乡高中生的教育效用都遵循先下降、后回升的变化趋势;在教育志向上,城市高中生无明显变化,而农村高中生教育志向上升并超越城市高中生;(2)高中生教育效用、教育志向受父母学历和学业成绩等微观因素影响,且受年代和城乡宏观社会历史因素调节。相比于其他年份,2010年时成绩较差学生的教育效用更低、2018年时成绩较差学生的教育志向更高;自1999年至2018年,低父母学历对农村高中生教育志向的影响方式由“枷锁效应”转变为“鞭策效应”。我国过去20年的社会变迁使城乡高中生对教育的价值认同发生系统性变化,且宏观社会历史因素的演变改变了教育的价值认同形成的微观机制。 展开更多
关键词 社会变迁 城乡差异 青少年 教育效用 教育志向
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