期刊文献+
共找到173,908篇文章
< 1 2 250 >
每页显示 20 50 100
Spatial-temporal Divergence Characteristics and Driving Factors of Green Economic Efficiency in the Yangtze River Economic Belt of China
1
作者 PAN Ting JIN Gui +1 位作者 ZENG Shibo WANG Rui 《Chinese Geographical Science》 SCIE CSCD 2024年第6期1158-1174,共17页
The spatial and temporal variation of green economic efficiency and its driving factors are of great significance for the construction of high-efficiency and low-consumption green development model and sustainable soc... The spatial and temporal variation of green economic efficiency and its driving factors are of great significance for the construction of high-efficiency and low-consumption green development model and sustainable socio-economic development.The research focused on the Yangtze River Economic Belt(YREB)and employed the miniumum distance to strong efficient frontier DEA(MinDs)model to measure the green economic efficiency of the municipalities in the region between 2008 and 2020.Then,the spatial autocorrelation model was used to analyze the evolution characteristics of its spatial pattern.Finally,Geodetector was applied to reveal the drivers and their interactions on green economic efficiency.It is found that:1)the overall green economic efficiency of the YREB from 2008 to 2020 shows a W-shaped fluctuating upward trend,green economic efficiency is greater in the downstream and smallest in the upstream;2)the spatial distribution of green economic efficiency shows clustering characteristics,with multi-core clustering based on‘city clusters-central cities'becoming more obvious over time;the High-High agglomeration type is mainly clustered in Jiangsu and Zheji-ang,while the Low-Low agglomeration type is clustered in the western Sichuan Plateau area and southwestern Yunnan;3)from input-output factors,whether it is the YREB as a whole or the upper,middle and lower reaches regions,the economic development level,labor input,and capital investment are the leading factors in the spatial-temporal evolution of green economic efficiency,with the com-prehensive influence of economic development level and pollution index being the most important interactive driving factor;4)from so-cio-economic factors,information technology drivers such as government intervention,transportation accessibility,information infra-structure,and Internet penetration are always high impact influencers and dominant interaction factors for green economic efficiency in the YREB and the three major regions in the upper,middle and lower reaches.Accordingly,the article puts forward relevant policy re-commendations in terms of formulating differentiated green transformation strategies,strengthening network leadership and informa-tion technology construction and coordinating multi-factor integrated development,which could provide useful reference for promoting synergistic green economic efficiency in the YREB. 展开更多
关键词 green economic efficiency miniumum distance to strong efficient frontier DEA(MinDs) spatial-temporal evolution Geo-detector Yangtze River Economic Belt(YREB) China
下载PDF
Enhanced Cooling Efficiency of Urban Trees on Hotter Summer Days in 70 Cities of China
2
作者 Limei YANG Jun GE +4 位作者 Yipeng CAO Yu LIU Xing LUO Shiyao WANG Weidong GUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第11期2259-2275,共17页
Increasing the urban tree cover percentage(TCP) is widely recognized as an efficient way to mitigate the urban heat island effect. The cooling efficiency of urban trees can be either enhanced or attenuated on hotter d... Increasing the urban tree cover percentage(TCP) is widely recognized as an efficient way to mitigate the urban heat island effect. The cooling efficiency of urban trees can be either enhanced or attenuated on hotter days, depending on the physiological response of urban trees to rising ambient temperature. However, the response of urban trees' cooling efficiency to rising urban temperature remains poorly quantified for China's cities. In this study, we quantify the response of urban trees' cooling efficiency to rising urban temperature at noontime [~1330 LT(local time), LT=UTC+8] in 17summers(June, July, and August) from 2003–19 in 70 economically developed cities of China based on satellite observations. The results show that urban trees have stronger cooling efficiency with increasing temperature, suggesting additional cooling benefits provided by urban trees on hotter days. The enhanced cooling efficiency values of urban trees range from 0.002 to 0.055℃ %-1 per 1℃ increase in temperature across the selected cities, with larger values for the lowTCP-level cities. The response is also regulated by background temperature and precipitation, as the additional cooling benefit tends to be larger in warmer and wetter cities at the same TCP level. The positive response of urban trees' cooling efficiency to rising urban temperature is explained mainly by the stronger evapotranspiration of urban trees on hotter days.These results have important implications for alleviating urban heat risk by utilizing urban trees, particularly considering that extreme hot days are becoming more frequent in cities under global warming. 展开更多
关键词 urban trees cooling efficiency China's cities EVAPOTRANSPIRATION SUMMER hot days
下载PDF
Enhancing the crystallinity and stability of perovskite solar cells with 4-tert-butylpyridine induction for efficiency exceeding 24%
3
作者 You Liu Lishuang Zheng +15 位作者 Kuanxiang Zhang Kun Xu Weicheng Xie Jue Zhang Yulu Tian Tianyuan Liu Hanzhong Xu Ruoming Ma Wei Huang Jiahui Chen Jusheng Bao Chen Chen Yongsheng Zhou Xuchun Wang Junming Chen Jungan Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期1-7,I0001,共8页
Perovskite solar cells(PSCs)have emerged as a promising photovoltaic technology because of their high light absorption coefficient,long carrier diffusion distance,and tunable bandgap.However,PSCs face challenges such ... Perovskite solar cells(PSCs)have emerged as a promising photovoltaic technology because of their high light absorption coefficient,long carrier diffusion distance,and tunable bandgap.However,PSCs face challenges such as hysteresis effects and stability issues.In this study,we introduced a novel approach to improve film crystallization by leveraging 4-tert-butylpyridine(TBP)molecules,thereby enhancing the performance and stability of PSCs.Our findings demonstrate the effective removal of PbI_(2)from the perovskite surface through strong coordination with TBP molecules.Additionally,by carefully adjusting the concentration of the TBP solution,we achieved enhanced film crystallinity without disrupting the perovskite structure.The TBP-treated perovskite films exhibit a low defect density,improved crystallinity,and improved carrier lifetime.As a result,the PSCs manufactured with TBP treatment achieve power conversion efficiency(PCE)exceeding 24%.Moreover,we obtained the PCE of 21.39%for the 12.25 cm^(2)module. 展开更多
关键词 4-tert-butylpyridine Film crystallization Perovskite solar cells Power conversion efficiency Stability improvement
下载PDF
A Loss-model-based Efficiency Optimization Control Method for Induction Traction System of High-speed Train under Emergency Self-propelled Mode
4
作者 Yutong Zhu Yaohua Li 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第2期227-239,共13页
Increasing attention has been paid to the efficiency improvement of the induction traction system of high-speed trains due to the high demand for energy saving. In emergency self-propelled mode, however, the dc-link v... Increasing attention has been paid to the efficiency improvement of the induction traction system of high-speed trains due to the high demand for energy saving. In emergency self-propelled mode, however, the dc-link voltage and the traction power of the motor are significantly reduced, resulting in decreased traction efficiency due to the low load and low speed operations. Aiming to tackle this problem, a novel efficiency improved control method is introduced to the emergency mode of high-speed train traction system in this paper. In the proposed method, a total loss model of induction motor considering the behaviors of both iron and copper loss is established. An improved iterative algorithm with decreased computational burden is then introduced, resulting in a fast solving of the optimal flux reference for loss minimization at each control period. In addition, considering the parameter variation problem due to the low load and low speed operations, a parameter estimation method is integrated to improve the controller's robustness. The effectiveness of the proposed method on efficiency improvement at low voltage and low load conditions is demonstrated by simulated and experimental results. 展开更多
关键词 efficiency optimization Induction motor Loss model control Motor drives Traction system
下载PDF
A method for Improving the Efficiency of Pear Tree Crossbreeding
5
作者 Jintao XU Longfei LI +5 位作者 Minghui JI Huan LIU Lijuan GAO Yong GUO Yingjie WANG Baofeng HAO 《Agricultural Biotechnology》 2024年第2期25-26,42,共3页
In view of the short blooming period of pear tree crossbreeding and the complexity of pollination process, a method that can improve the efficiency of crossbreeding of pear trees was provided. Meanwhile, this method c... In view of the short blooming period of pear tree crossbreeding and the complexity of pollination process, a method that can improve the efficiency of crossbreeding of pear trees was provided. Meanwhile, this method can also be applied to the study of pollen xenia effect, pollination tree selection and pure pollen collection in pear tree cultivation. 展开更多
关键词 Pear tree Cross breeding efficiency METHOD
下载PDF
Methods to increase the diagnostic efficiency of endoscopic ultrasound-guided fine-needle aspiration for solid pancreatic lesions:An updated review
6
作者 Xin Yang Zi-Ming Liu +5 位作者 Xue Zhou Fan Yang Wen-Zhuang Ma Xin-Zhu Sun Si-Yu Sun Nan Ge 《World Journal of Gastrointestinal Endoscopy》 2024年第3期117-125,共9页
Endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA)is a means to procure adequate specimens for histological and cytologic analysis.The ideal EUS-FNA should be safe,accurate,and have a high sample adequacy ra... Endoscopic ultrasound-guided fine-needle aspiration(EUS-FNA)is a means to procure adequate specimens for histological and cytologic analysis.The ideal EUS-FNA should be safe,accurate,and have a high sample adequacy rate and low adverse events rate.In recent years,many guidelines and trials on EUS-FNA have been published.The purpose of this article is to provide an update on the influence of some of the main factors on the diagnostic efficiency of EUS-FNA as well as a rare but serious complication known as needle tract seeding. 展开更多
关键词 Endoscopic ultrasound EUS-FNA Pancreatic cancer Diagnostic efficiency
下载PDF
Spatio-temporal variation and relationship between agricultural efficiency and irrigation intensity in a semi-arid region of India
7
作者 Shibu DAS Kaushal Kumar SHARMA +2 位作者 Suranjan MAJUMDER Debabrata DAS Indrajit Roy CHOWDHURY 《Regional Sustainability》 2024年第2期123-139,共17页
A surging population in Karnataka State,a semi-arid region in India,poses a threat to both food security and livelihood sustainability,necessitating a concentrated effort to bolster agricultural efficiency and achieve... A surging population in Karnataka State,a semi-arid region in India,poses a threat to both food security and livelihood sustainability,necessitating a concentrated effort to bolster agricultural efficiency and achieve United Naton’s Sustainable Development Goal 2(zero hunger).Therefore,in order to address the pressing issue of food scarcity in Karnataka,this study meticulously examined the spatio-temporal variation of agricultural efficiency and irrigation intensity in Karnataka,uncovering its significant dependence of agricultural efficiency on irrigation intensity.Specifically,this study used a one-way analysis of variance(ANOVA)to ascertain significant differences in the means of agricultural efficiency and irrigation intensity during 2004-2005 and 2018-2019.This study showed that the maximum improvement in agricultural efficiency index was recorded in Belgaum(40.24),Gulbarga(24.77),and Yadgir districts(22.92)between 2004-2005 and 2018-2019,which indicated the progressing trend and better scope for agriculture extension.On the contrary,some districts expressed threat(a decline of above 20.00 of agricultural efficiency index)and needed special care for the improvement of agricultural efficiency in four northern districts(Bagalkot,Bidar,Raichur,and Bijapur),three southern districts(Chitradurga,Chikballapur and Hassan),and two southern districts(Koppal and Gadag)in Karnataka.During 2004-2005,irrigation intensity varied from 3.19%to 56.39%,with the lowest irrigation intensity in Kodagu District and the highest irrigation intensity in Shimoga District.During 2018-2019,irrigation intensity changed from 0.77%to 72.77%,with the lowest irrigation intensity in Kodagu District and the highest in Dakshin Kannad District.Moreover,the research scrutinized the complex relationship between agricultural efficiency and irrigation intensity,with the correlation coefficient increased from 0.162 during 2004-2005 to 0.255 during 2018-2019.It implies that in both periods,a low positive correlation existed between these two variables.Over time,several factors(high-yield seeds and chemical fertilizers)other than irrigation intensity gradually became essential for agricultural efficiency.This research offers a wealth of valuable insights for regional planners and policy-makers contending with comparable challenges in various regions of India and other developing countries. 展开更多
关键词 Agricultural efficiency Irrigation intensity One-way analysis of variance(ANOVA) Food security KARNATAKA
下载PDF
Are cities greener because of innovation?Independent innovation policy and green economic efficiency
8
作者 Zhuoji Zheng Xueqin Li +3 位作者 Mengjie Yu Yuan Li Xianfeng Han Yuping Yin 《Chinese Journal of Population,Resources and Environment》 2024年第2期118-126,共9页
The national independent innovation demonstration zone(NIIDZ)is an independent innovation policy that plays a crucial role in implementing strategies.Given the importance of the NIIDZ,this study uses panel data of 278... The national independent innovation demonstration zone(NIIDZ)is an independent innovation policy that plays a crucial role in implementing strategies.Given the importance of the NIIDZ,this study uses panel data of 278 prefecture-level cities in China from 2006 to 2020 and empirically examines the effect and internal mechanism of the NIIDZ on green economic efficiency(GEE)using the difference-in-difference model(DID).The results show that the NIIDZ effectively enhances the growth of GEE,and the results remain valid through several robustness tests,such as year-by-year propensity score matching.The transmission mechanism suggests that the NIIDZ indirectly drives GEE by accelerating scientific and technological investment,promoting talent concentration,and optimizing the industrial structure.Moreover,heterogeneity analysis reveals that the promotion effect of the NIIDZ on GEE is more prominent in the eastern region and high green development level areas.The study’s findings can serve as a reference for China to further utilize the policy effectiveness of the NIIDZ and accelerate the high-quality development of the green economy in the future. 展开更多
关键词 National innovation independent demonstration Zone(NIIDZ) Green economy efficiency(Gee) Difference-in-difference model(DID)
下载PDF
A Study of the Impact of the Digital Economy on the Efficiency of Urban Green Economy--Based on the Yangtze River Delta City Cluster
9
作者 LU Yang MIN Tianwei 《Management Studies》 2024年第1期1-8,共8页
This paper adopts the non-expected output-super-efficiency SBM(Slacks-Based Model)model and principal component analysis to calculate the green economy efficiency and the digital economy level of 27 prefecture-level c... This paper adopts the non-expected output-super-efficiency SBM(Slacks-Based Model)model and principal component analysis to calculate the green economy efficiency and the digital economy level of 27 prefecture-level cities in China’s Yangtze River Delta urban agglomeration between 2011 and 2019,respectively,and examines the impact of the digital economy on the green economy efficiency by using benchmark regression and mechanism analysis.The findings show that,first,the digital economy has a significant contribution to the green economic efficiency of cities,and this conclusion still holds after robustness tests such as replacing explanatory and interpreted variables and introducing province-fixed effects.Second,through the mechanism test,it is found that the digital economy can indirectly promote urban green economic efficiency through the positive mechanism effect of promoting industrial structure upgrading. 展开更多
关键词 digital economy urban green economy efficiency undesired output-super-efficiency SBM model
下载PDF
Quantitative Description of the Effects of Sweep Efficiency and Displacement Efficiency during Chemical Flooding on a Heterogeneous Reservoir 被引量:6
10
作者 沈平平 袁士义 +2 位作者 邓宝荣 宋杰 沈奎友 《Petroleum Science》 SCIE CAS CSCD 2004年第3期41-48,77,共9页
The processes of flooding—water flooding, polymer flooding and ternary combination flooding—were simulated respectively on a 2-D positive rhythm profile geological model by using the ASP numerical modeling softw... The processes of flooding—water flooding, polymer flooding and ternary combination flooding—were simulated respectively on a 2-D positive rhythm profile geological model by using the ASP numerical modeling software developed by RIPED (Yuan, et al. 1995). The recovery coefficient, remaining oil saturation, sweep efficiency and displacement efficiency were calculated and correlated layer by layer. The results show that the sweep efficiency and displacement efficiency work different effects on different layers in the severely heterogeneous reservoir. The study shows that the displacement efficiency and sweep efficiency play different roles in different layers for severely heterogeneous reservoirs. The displacement efficiency contributes mainly to the high permeability zones, the sweep efficiency to the low permeability zones, both of which contribute to the middle permeable zones. To improve the sweep efficiency in the low permeability zones is of significance for enhancing the whole recovery of the reservoir. It is an important path for improving the effectiveness of chemical flooding in the severely heterogeneous reservoirs to inject ternary combination slug after profile control. 展开更多
关键词 Chemical flooding displacement efficiency sweep efficiency recovery efficiency heterogenous reservoir
下载PDF
Effects of Different Irrigation Amounts on Water Consumption and Water Use Efficiency of Greenhouse Cucumber 被引量:6
11
作者 郭生虎 孔德杰 +2 位作者 张源沛 郑国宝 朱金霞 《Agricultural Science & Technology》 CAS 2010年第9期217-220,共4页
[Objective] This study was to investigate the effects of different irrigation amount on water consumption and water use efficiency of greenhouse cucumber.[Method]Under the condition of drip irrigation with different w... [Objective] This study was to investigate the effects of different irrigation amount on water consumption and water use efficiency of greenhouse cucumber.[Method]Under the condition of drip irrigation with different water amounts in sunlight greenhouse of the arid areas in Ningxia,the soil water was measured and the water consumption of crop was calculated.[Result]When irrigation amount was 563 mm,the water consumption as a whole gradually increased with the delay of growth period,reached peak during the thriving stage of fruit setting,and then gradually declined;in each treatment,the daily water consumption increased with the increasing of irrigation amount during each growth period.However,the consumption of soil moisture reduced with the significant increase of irrigation.563 mm of irrigation amount could meet the water requirements of cucumber and began to add water to soil,and water utilization efficiency could reach 33.4 kg/m3.[Conclusion]The research had provided theoretical basis for water management in the production process of greenhouse cucumber. 展开更多
关键词 GReeNHOUSE CUCUMBER Irrigation amount Water consumption Water utilization efficiency
下载PDF
Progress in the Breeding of Soybean for High Photosynthetic Efficiency 被引量:11
12
作者 郝乃斌 杜维广 +6 位作者 戈巧英 张桂茹 李卫华 满为群 彭德川 白克智 匡廷云 《Acta Botanica Sinica》 CSCD 2002年第3期253-258,共6页
Studies for many years have indicated that the seed yield of (Glycine max L. Merr.) soybean can be increased by increasing photosynthetic efficiency. The yield of cultivars with high photosynthetic efficiency (HPE) in... Studies for many years have indicated that the seed yield of (Glycine max L. Merr.) soybean can be increased by increasing photosynthetic efficiency. The yield of cultivars with high photosynthetic efficiency (HPE) increased by 30% - 40% in comparison with the cultivars with normal photosynthetic efficiency, indicating that the breeding of soybean by increasing RPE may have a bright prospect. HPE breeding can be used as the temporal monitoring in the breeding process to avoid the divergency of the predetermined goal, although HPE breeding does not shorten the breeding time. It was observed that limited C-4 pathway exists in soybean leaf and pod, suggesting that by increasing the genetic expression of some C-4 enzymes in C-3 crops through traditional or genetic engineering techniques, new breakthroughs in increasing the photosynthetic efficiency of C-3 plant may be practicable in the future. 展开更多
关键词 SOYBEAN C-4 pathway enzyme high photosynthetic efficiency breeding
下载PDF
Difference in Absorption of N, P and K among Different-Phosphorus Efficiency Soybean Genotypes at the Seedling Stage 被引量:1
13
作者 张彦丽 谷思玉 +2 位作者 律凤霞 齐虹凌 杨松鹏 《Agricultural Science & Technology》 CAS 2014年第12期2145-2149,共5页
The low-phosphorus efficiency soybean genotypes, D03, D05, D17 and D18, and the high-phosphorus efficiency soybean genotypes, D31, D34, D37 and D38 were selected. The soil culture experiment was conducted. There were ... The low-phosphorus efficiency soybean genotypes, D03, D05, D17 and D18, and the high-phosphorus efficiency soybean genotypes, D31, D34, D37 and D38 were selected. The soil culture experiment was conducted. There were 2 treat- ments, high phosphorus (+P) and low phosphorus (-P). The difference in absorption of N, P and K among different-phosphorus efficiency soybean genotypes at the seedling stage was analyzed. The results showed in the low phosphorus (-P) treat- ment, the P absorption amount differed among roots, stems and leaves of different high-phosphorus efficiency genotypes. The P absorption amount was positively relat- ed (P〈0.05, P〈0.01) to the dry weights of root, stem and leaves, but was negative- ly related to the utilization efficiency of phosphorus (P〉0.05). The N and K absorp- tion amounts of root, stem and leaves all trended to decrease. The low phosphorus stress would inhibit the absorption of N, P and K in soybean plants at the seedling stage. However, the adaptability of the high-phosphorus efficiency soybean geno- types to low phosphorus stress was significantly higher than that of low-phosphorus efficiency genotypes. 展开更多
关键词 SOYBEAN Seedling stage Phosphorus efficiency Phosphorus stress
下载PDF
HIGH EFFICIENCY COOLING TECHNOLOGY BASED ON GREEN MANUFACTURING 被引量:1
14
作者 安庆龙 傅玉灿 +3 位作者 徐九华 王云峰 任守良 徐鸿钧 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第3期230-233,共4页
Green manufacturing (GM) and high efficiency machining technology are inevitable trends in the field of advanced manufacturing of the 21st century. To ensure green and high-efficiency machining, a new high efficienc... Green manufacturing (GM) and high efficiency machining technology are inevitable trends in the field of advanced manufacturing of the 21st century. To ensure green and high-efficiency machining, a new high efficiency cooling technology-cryogenic pneumatic mist jet impinging cooling (CPMJI) technology is presented. For obtaining the best cooling effect, a little quantity of coolant is carried by high speed cryogenic air (-20 C ) and reaches the machining zone in the form of mist jet to enhance heat transfer. Experimental results indicate that under the conditions of 40 m/s in the jet impinging speed and 10 mm in the jet impinging distance, the critical heat flux(CHF) nearly reaches 6× 10^7 W/m^2, more than six times of the CHF of the grinding burn with a value of (8~10)×10^6 W/m^2. 展开更多
关键词 high efficiency cooling mist jet impinging enhancing heat transfer critical heat flux
下载PDF
Effects of Potassium Fertilizing Rates on Yield, Fiber Quality and Potassium Use Efficiency of Three Hybrid Cotton Cultivars 被引量:1
15
作者 冯正锐 刘爱玉 +3 位作者 易九红 李瑞莲 王欣悦 邹茜 《Agricultural Science & Technology》 CAS 2014年第2期200-204,共5页
The effects of potassium (K) application rates on the yield, fiber quality and K fertilizer use efficiency of three hybrid cotton varieties (Jin102, Xiangzamian8, Siyang328) were studied in field experiment. Ferti... The effects of potassium (K) application rates on the yield, fiber quality and K fertilizer use efficiency of three hybrid cotton varieties (Jin102, Xiangzamian8, Siyang328) were studied in field experiment. Fertilizer rates of K2O 135 and 270 kg/hm2, representing 1x and 2x recommended K rates, were applied, no application of k fertilizer as the CK. The results show that the lint yield increased 39.13%-57.48%with potassium application, highly significantly. Al yield components of the three hy-brid cotton varieties increased with the increase of K application amounts. The bol number per plant, single bol weight and lint percentage were increased by 14.24%-40.29%, 3.59%-15.51% and 0.16%-4.89%, respectively, and the fiber length and specific strength also increased with the increasing K application amounts, showing no significant influence on Micronaire. When the K application amounts increased from 135 to 270 kg/hm2, the partial factor productivity (PFPk) reduced by 45.93%-48.01%, and the agronomic efficiency (AEk) reduced by 37.1%-42.9%. The PFPk and KE (K efficiency coefficients) of S328 were the highest among the three varieties, which also showed the strongest resistance to low potassium stress, and with no potassi-um fertilizer application (K0), the lint yield of S328 was 5.54% and 11.19% higher than that of X8 and J102. The AEk of J102 was the highest, and its reward of K fertilizer was the greatest among the three varieties. 展开更多
关键词 Hybrid cotton Amount of Potassium Fertilizer Application YIELD Quality K use efficiency
下载PDF
Suitable Date of Seeding, Planting Density and Water Use Efficiency for Propagation of Stock Seed Potato in Mountainous Region of Southwest Sichuan 被引量:2
16
作者 沈学善 罗李飞 +1 位作者 李春荣 黄钢 《Agricultural Science & Technology》 CAS 2012年第9期1904-1907,共4页
[Objective] The experiment was conducted to study suitable date of seed- ing and density of spring potato at the stock breeding base in Ebian County at an elevation of 1 200 to 1 500 m. [Methods] Virus-free Potato "C... [Objective] The experiment was conducted to study suitable date of seed- ing and density of spring potato at the stock breeding base in Ebian County at an elevation of 1 200 to 1 500 m. [Methods] Virus-free Potato "Chuanyu 13" was used as material to study the effects of date of seeding and density on growing period, germination rate, yield and water use efficiency of spring potato in the field. [Result] With the postponement of date of seeding, the days from sowing to germination shortened, while the germination rate, the number of tubers per plant, the number of middle and small tubers in a group, yield and water use efficiency all increased. Planting density had no effects on the days from sowing to germination and the ger- mination rate, while the number of tubers per ptant, the number of middle and small tubers in a group, yield and water use efficiency increased significantly along with the increasing planting density. [Conclusion] At an elevation of 1 200 m to 1 250 m in Ebian County, the suitable date of seeding for potato was from February 9 to March 1, and the suitable planting density was 12×10^4 plants per hm^2, however, in the optimum planting density has not been found so that it needs further research, 展开更多
关键词 Date ofseedingi Planting density Stock seed YIELD Water use efficiency
下载PDF
Research on Relationship between Recovery Ability after Drought Stress-rewatering and Water Use Efficiency of Winter Wheat Varieties
17
作者 黄桂荣 张欣莹 +1 位作者 王雅静 钟秀丽 《Agricultural Science & Technology》 CAS 2017年第12期2236-2240,2245,共6页
The study aims at exploring the possibility of using the recovery ability af- ter drought stress-rewatering at vegetative growth stage as the evaluating index in water use efficiency (WUE) of winter wheat varieties.... The study aims at exploring the possibility of using the recovery ability af- ter drought stress-rewatering at vegetative growth stage as the evaluating index in water use efficiency (WUE) of winter wheat varieties. 'Jing 411 ', 'Jinmai 47' and their 34 near isogenic lines (NILs) were used as test materials. Semi-automatic rainproof shelter and the percolating pools were used for simulating drought treat- ment. After suffering severe drought stress, winter wheat crops were rewatered at early jointing stage. The biomass accumulation after rewatering was determined as recovery ability index. In the meanwhile, plant height in the end of vegetative growth stage was measured, and WUE of varieties/lines was also determined. Thereafter, the differences in recovery ability, plant height and the population WUE, together with the correlation between recovery ability and population WUE were analyzed, respectively. The results showed that there were significant differences in recovery ability among some varieties/lines. The recovery ability was affected by both geno- type and environment, and the interaction existed in these two factors. Significant differences existed in plant height and population WUE among the 34 NILs along with their parents. There was a significantly positive correlation between recovery ability and plant height of varieties/lines. Recovery ability and plant height were very significantly and positively correlated with population yield WUE respectively. The re- sults indicated that recovery ability after drought stress-rewatering could be used as an evaluating index of population WUE under drought condition. 展开更多
关键词 Drought stress-rewatering Near isogenic lines Recover ability Plantheight Water use efficiency
下载PDF
Research on the special role of career planning in accelerating the efficiency of regular teaching for English major students
18
作者 周王宏 苏丽 《海外英语》 2011年第14期391-392,共2页
The teaching contents of English major need to be designed flexibly with revolving around career planning as it is helpful for teachers to acquire creative thoughts and ideas in teaching.Especially,this can surely gua... The teaching contents of English major need to be designed flexibly with revolving around career planning as it is helpful for teachers to acquire creative thoughts and ideas in teaching.Especially,this can surely guarantee the remarkable efficiency of English major teaching. 展开更多
关键词 CAReeR planning REGULAR TEACHING English MAJOR efficiency
下载PDF
Novel interface engineering of LDH-based materials on Mg alloy for efficient photocatalytic systems considering the geometrical linearity of condensed phosphates 被引量:3
19
作者 Mosab Kaseem Ananda Repycha Safira Arash Fattah-alhosseini 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期267-280,共14页
This study presents a facile and rapid method for synthesizing novel Layered Double Hydroxide(LDH)nanoflakes,exploring their application as a photocatalyst,and investigating the influence of condensed phosphates'g... This study presents a facile and rapid method for synthesizing novel Layered Double Hydroxide(LDH)nanoflakes,exploring their application as a photocatalyst,and investigating the influence of condensed phosphates'geometric linearity on their photocatalytic properties.Herein,the Mg O film,obtained by plasma electrolysis of AZ31 Mg alloys,was modified by growing an LDH film,which was further functionalized using cyclic sodium hexametaphosphate(CP)and linear sodium tripolyphosphate(LP).CP acted as an enhancer for flake spacing within the LDH structure,while LP changed flake dispersion and orientation.Consequently,CP@LDH demonstrated exceptional efficiency in heterogeneous photocatalysis,effectively degrading organic dyes like Methylene blue(MB),Congo red(CR),and Methyl orange(MO).The unique cyclic structure of CP likely enhances surface reactions and improves the catalyst's interaction with dye molecules.Furthermore,the condensed phosphate structure contributes to a higher surface area and reactivity in CP@LDH,leading to its superior photocatalytic performance compared to LP@LDH.Specifically,LP@LDH demonstrated notable degradation efficiencies of 93.02%,92.89%,and 88.81%for MB,MO,and CR respectively,over a 40 min duration.The highest degradation efficiencies were observed in the case of the CP@LDH sample,reporting 99.99%for MB,98.88%for CR,and 99.70%for MO.This underscores the potential of CP@LDH as a highly effective photocatalyst for organic dye degradation,offering promising prospects for environmental remediation and water detoxification applications. 展开更多
关键词 Plasma electrolysis Layered Double Hydroxide Condensed phosphates Adsorption capacity Photocatalytic efficiency
下载PDF
Understanding Bridging Sites and Accelerating Quantum Efficiency for Photocatalytic CO_(2) Reduction 被引量:2
20
作者 Kangwang Wang Zhuofeng Hu +8 位作者 Peifeng Yu Alina M.Balu Kuan Li Longfu Li Lingyong Zeng Chao Zhang Rafael Luque Kai Yan Huixia Luo 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第1期68-84,共17页
We report a novel double-shelled nanoboxes photocatalyst architecture with tailored interfaces that accelerate quantum efficiency for photocatalytic CO_(2) reduction reaction(CO_(2)RR)via Mo–S bridging bonds sites in... We report a novel double-shelled nanoboxes photocatalyst architecture with tailored interfaces that accelerate quantum efficiency for photocatalytic CO_(2) reduction reaction(CO_(2)RR)via Mo–S bridging bonds sites in S_(v)–In_(2)S_(3)@2H–MoTe_(2).The X-ray absorption near-edge structure shows that the formation of S_(v)–In_(2)S_(3)@2H–MoTe_(2) adjusts the coordination environment via interface engineering and forms Mo–S polarized sites at the interface.The interfacial dynamics and catalytic behavior are clearly revealed by ultrafast femtosecond transient absorption,time-resolved,and in situ diffuse reflectance–Infrared Fourier transform spectroscopy.A tunable electronic structure through steric interaction of Mo–S bridging bonds induces a 1.7-fold enhancement in S_(v)–In_(2)S_(3)@2H–MoTe_(2)(5)photogenerated carrier concentration relative to pristine S_(v)–In_(2)S_(3).Benefiting from lower carrier transport activation energy,an internal quantum efficiency of 94.01%at 380 nm was used for photocatalytic CO_(2)RR.This study proposes a new strategy to design photocatalyst through bridging sites to adjust the selectivity of photocatalytic CO_(2)RR. 展开更多
关键词 Quantum efficiency Electronic structure Steric interaction Bridging sites CO_(2)reduction
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部