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Improvement of Concrete Properties and Reinforcing Steel Inhibition Using a Natural Product Admixture
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作者 S.H. Tantawi (Building Research Institute, Dokki, Cairo, Egypt)I.Z.Selim (Physical Chemistry Dept., National Research Center, Dokki, Cairo, Egypt (To whom correspondence should be addressed) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1996年第2期95-99,共5页
The use of a natural white juice, taken from magrabe banana stem, as concrete admixture to improve mechanical and physicrvchemical properties of concrete has been studied. The compressive strength, bulk density the fr... The use of a natural white juice, taken from magrabe banana stem, as concrete admixture to improve mechanical and physicrvchemical properties of concrete has been studied. The compressive strength, bulk density the free lime liberated during hydration and the combined water content were determined. The results indicate that the admixture acts as a retarder in most cases and as accelerator in some ones. Also, the admixture effect on the corrosion resistance of the reinforcing steel against surrounding aggressive media has been investigated using galvanostatic polarization technique. The addition of 0.2% admixture leads to the more inhibition of the steel 展开更多
关键词 pH FIGURE Improvement of Concrete Properties and Reinforcing Steel Inhibition using a Natural Product Admixture OH
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ZTE's Optical Transmission Products Used in National Backbone Network of Indonesia
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作者 Yu Huihui (Comprehensive Product Division,ZTE Corporation,Shenzhen 518004,China) 《ZTE Communications》 2004年第2期33-35,共3页
1 Technical Features of ZTE’sDWDM SystemThe toll backbone wave division equipmentof ZXWM M900 backbone transmissionplatform is well designed forlarge-capacity optical transmission. It canfully satisfy the networking ... 1 Technical Features of ZTE’sDWDM SystemThe toll backbone wave division equipmentof ZXWM M900 backbone transmissionplatform is well designed forlarge-capacity optical transmission. It canfully satisfy the networking and managementrequirements of diversified users and be fit forvarious toll backbone networks. The systemsupports up to 40 working wavelengths and up to400 Gb/s transmission capacity, and thewavelength selection and interval are in strictcompliance with ITU-T Recommendations. It 展开更多
关键词 ZTE’s Optical Transmission products Used in National Backbone Network of Indonesia In
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Production of Carbon Nanotubes over Pre-reduced LaCoO_3 Using Fluidized-bed Reactor
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《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第11期1031-1034,共4页
关键词 CNTs Production of Carbon Nanotubes over Pre-reduced LaCoO3 using Fluidized-bed Reactor OVER
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Heterosis Analysis of Nitrogen Use Efficiency for Grain Production of Brassica napus L. 被引量:2
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作者 石剑飞 殷璀艳 +4 位作者 刘荣 唐瑶 杨光 左青松 冷锁虎 《Agricultural Science & Technology》 CAS 2010年第1期45-47,共3页
[Objective]The aim was to study heterosis of N use efficiency for grain production (NUEg) of Brassica napus L. and provide theoretical basis for breeding N-efficient cultivars. [Method]Dry matter production and N co... [Objective]The aim was to study heterosis of N use efficiency for grain production (NUEg) of Brassica napus L. and provide theoretical basis for breeding N-efficient cultivars. [Method]Dry matter production and N content of six B.napus parents (Zheshuang 3,Yangyou 7,ZJ1,Shilijia,Ningyou 14 and Huyou 16) and their F1 combinations from 6 × 6 complete diallel cross in maturity stage under two N levels were measured; heterosis of NUEg,combining ability and heritability size were analyzed and calculated. [Result]The results showed that NUEg has obvious heterosis; combining ability variance analysis indicated that NUEg was mainly controlled by additive,dominant and cytoplasmic effects; genetic variance analysis showed that additive effects and dominance effects were all significant in low nitrogen fertilizer and dominance effects were significant in high nitrogen fertilizer. [Conclusion]NUEg of B.napus has obvious heterosis. 展开更多
关键词 Brassica napus L. Nitrogen use efficiency for grain production HETEROSIS
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Comparative effects of nitrogen application on growth and nitrogen use in a winter wheat/summer maize rotation system 被引量:8
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作者 YIN Min-hua LI Yuan-nong XU Yuan-bo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第9期2062-2072,共11页
The application of fertilizer in agricultural production has become universally common for achieving high crop yields and economic benefits, but it has potential impacts on food safety, energy crisis and environmental... The application of fertilizer in agricultural production has become universally common for achieving high crop yields and economic benefits, but it has potential impacts on food safety, energy crisis and environmental pollution. Optimal management of fertilization is thus necessary for maintaining sustainable agriculture. Two-year(2013–2015) field experiment was conducted, in Yangling(108°24′E, 34°20′N, and 521 m a.s.l.), Shaanxi Province, China, to explore the effects of different nitrogen(N) applications on biomass accumulation, crop N uptake, nitrate N(NO_3~–-N) distribution, yield, and N use with a winter wheat/summer maize rotation system. The N applications consisted of conventional urea(U)(at 80(U80), 160(U160), and 240(U240) kg N ha^(–1); 40% applied as a basal fertilizer and 60% top-dressed at jointing stage) and controlled-release urea(CRU)(at 60(C60), 120(C120), 180(C180), and 240(C240) kg N ha~(^(–1)); all applied as a basal fertilizer) with no N application as a control(CK). The continuous release of N from CRU matched well with the N demands of crop throughout entire growing stages. Soil NO_3~–-N content varied less and peaked shallower in CRU than that in urea treatments. The differences, however, were smaller in winter wheat than that in summer maize seasons. The average yield of summer maize was the highest in C120 in CRU treatments and in U160 in urea treatments, and apparent N use efficiency(NUE) and N agronomic efficiency(NAE) were higher in C120 than in U160 by averages of 22.67 and 41.91%, respectively. The average yield of winter wheat was the highest in C180 in CRU treatments and in U240 in urea treatments with C180 increasing NUE and NAE by averages of 14.89 and 35.62% over U240, respectively. The annual yields under the two N fertilizers were the highest in C120 and U160. The results suggested that CRU as a basal fertilizer once could be a promising alternative of urea as split application in semiarid areas. 展开更多
关键词 controlled-release urea nitrogen availability soil fertility nitrogen use efficiency soil productivity
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Responses of water productivity to irrigation and N supply for hybrid maize seed production in an arid region of Northwest China 被引量:5
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作者 RAN Hui KANG Shaozhong +4 位作者 LI Fusheng DU Taisheng DING Risheng LI Sien TONG Ling 《Journal of Arid Land》 SCIE CSCD 2017年第4期504-514,共11页
Water and nitrogen(N) are generally two of the most important factors in determining the crop productivity. Proper water and N managements are prerequisites for agriculture sustainable development in arid areas. Fie... Water and nitrogen(N) are generally two of the most important factors in determining the crop productivity. Proper water and N managements are prerequisites for agriculture sustainable development in arid areas. Field experiments were conducted to study the responses of water productivity for crop yield(WP_(Y-ET)) and final biomass(WP_(B-ET)) of film-mulched hybrid maize seed production to different irrigation and N treatments in the Hexi Corridor, Northwest China during April to September in 2013 and also during April to September in 2014. Three irrigation levels(70%–65%, 60%–55%, and 50%–45% of the field capacity) combined with three N rates(500, 400, and 300 kg N/hm^2) were tested in 2013. The N treatments were adjusted to 500, 300, and 100 kg N/hm^2 in 2014. Results showed that the responses of WP_(Y-ET) and WP_(B-ET) to different irrigation amounts were different. WP_(Y-ET) was significantly reduced by lowering irrigation amounts while WP_(B-ET) stayed relatively insensitive to irrigation amounts. However, WP_(Y-ET) and WP_(B-ET) behaved consistently when subjected to different N treatments. There was a slight effect of reducing N input from 500 to 300 kg/hm^2 on the WP_(Y-ET) and WP_(B-ET), however, when reducing N input to 100 kg/hm^2, the values of WP_(Y-ET) and WP_(B-ET) were significantly reduced. Water is the primary factor and N is the secondary factor in determining both yield(Y) and final biomass(B). Partial factor productivity from applied N(PFP_N) was the maximum under the higher irrigation level and in lower N rate(100–300 kg N/hm^2) in both years(2013 and 2014). Lowering the irrigation amount significantly reduced evapotranspiration(ET), but ET did not vary with different N rates(100–500 kg N/hm^2). Both Y and B had robust linear relationships with ET, but the correlation between B and ET(R^2=0.8588) was much better than that between Y and ET(R^2=0.6062). When ET increased, WP_(Y-ET) linearly increased and WP_(B-ET) decreased. Taking the indices of Y, B, WP_(Y-ET), WP_(B-ET) and PFP_N into account, a higher irrigation level(70%–65% of the field capacity) and a lower N rate(100–300 kg N/hm^2) are recommended to be a proper irrigation and N application strategy for plastic film-mulched hybrid maize seed production in arid Northwest China. 展开更多
关键词 water use efficiency water stress nitrogen use efficiency evapotranspiration water productivity for yield water productivity for biomass arid region
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A study on the bioenergy crop production function of land use in China 被引量:2
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作者 ZHANG Kun YU Yao +1 位作者 BAO Chun-hong WANG Tao 《Ecological Economy》 2010年第4期407-414,共8页
Based on the analysis of the bioenergy crop production function of land use,combined with the status quo of Chinese land use,the cultivation of energy plants and the bioenergy crop production function of land use had ... Based on the analysis of the bioenergy crop production function of land use,combined with the status quo of Chinese land use,the cultivation of energy plants and the bioenergy crop production function of land use had been analyzes and discusses in this paper.Results show that there were a lot of unused lands and marginal lands which can be planted bioenergy crops to perform the bioenergy crop production function of land use with great potentials;and currently there were no food production problems.Therefore,it was very important for China to emphasize bioenergy crops planting in order to fully use land resources in our country,moderate the energy crisis and increase peasants' income. 展开更多
关键词 Land use Bioenergy crop production function of land use BIOENERGY Bioenergy crops Increase of peasants' income
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Researcher Urges Less Use of Anti-Bacteria Products
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作者 Will Dunham 苏玉美 《当代外语研究》 2004年第1期6-7,共2页
现在消毒柜,消毒水倍受许多有"洁癖"的人的青睐。同时,我们也经常听到悉心的父母对自己的孩子说:不要碰那个东西,上面有细菌。久而久之,人们一谈起细菌,就似乎是流行病、传染病如流感、疟疾、肝炎、肺结核等的代名词。现在研... 现在消毒柜,消毒水倍受许多有"洁癖"的人的青睐。同时,我们也经常听到悉心的父母对自己的孩子说:不要碰那个东西,上面有细菌。久而久之,人们一谈起细菌,就似乎是流行病、传染病如流感、疟疾、肝炎、肺结核等的代名词。现在研究表明,其实,细菌并没那么可怕。相反,有时候没有细菌的"真空"世界对你和你孩子的抗病能力的培养反而不利。物极必反,抗菌和抗生素的随意使用很可能招致"超级细菌"的滋生。 展开更多
关键词 超级病菌 Researcher Urges Less Use of Anti-Bacteria products 清洁剂 抗生素 传染病
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Comparative analysis of greenhouse gas emission inventory for Pakistan:Part I energy and industrial processes and product use 被引量:1
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作者 Kaleem Anwar MIR Chunkyoo PARK +1 位作者 Pallav PUROHIT Seungdo KIM 《Advances in Climate Change Research》 SCIE CSCD 2020年第1期40-51,共12页
In order to further improve the accuracy and reliability and reduce uncertainties in the national GHG inventories for Pakistan,this study call for using 2006 IPCC Guidelines,to help to identify the national targets fo... In order to further improve the accuracy and reliability and reduce uncertainties in the national GHG inventories for Pakistan,this study call for using 2006 IPCC Guidelines,to help to identify the national targets for GHG mitigation with respect to the nationally determined contributions(NDCs).GHG(CO2,CH4,and N20)inventories for Pakistan have been developed by conducting a detailed sectoral assessment of IPCC source sectors,energy,industrial processes and product use(IPPU),agriculture,forestry and other land use(AFOLU),and the waste sector.Further,sector wise comparative analysis of GHG inventories(1994-2017)based on the 2006 and 1996 IPCC Guidelines have also been presented.Results indicated an average relative difference of 4%in total GHG emissions(CO2 equivalent)from energy sector between 2006 and 1996 IPCC Guidelines.With 3.6%average annual growth rate based on 2006 IPCC Guidelines,CO2 from energy sector remained the most abundant GHG emitted,followed by CH4 and N2O.While the average absolute difference in emissions of CH4 and N20 from the energy sector is notable,the total estimated GHG emissions by 2006 IPCC Guidelines duplicate those by 1996 IPCC Guidelines.In the mineral industry with 2006 IPCC Guidelines,an average annual growth rate of 6.7%is observed,contributing 64%of total IPPU sector CO2 emissions.Nevertheless,the relative difference between the two Guidelines in overall IPPU sector emissions remained negligible.There might be a need for switching to 2006 IPCC Guidelines to consider more parameters such as additional source sectors and new default emission factors that fit into national circumstances. 展开更多
关键词 Greenhouse gas Emission inventory Energy sector Industrial processes and product use Pakistan
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