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动手操作 合作交流 发展能力——人教版二年级上册“认识米,用米量”教学设计
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作者 罗振兴 《福建教育》 2003年第07A期46-47,共2页
关键词 动手操作 合作交流 人教版 二年级 上册 “认识米 用米量” 教学设计 小学 数学教学 教学目标
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“认识米 用米量”教案设计
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作者 李红 《小学教学参考(数学版)》 2004年第7期38-40,共3页
教学内容:人教版二年级上册“厘米和米的认识”的第二课时内容。
关键词 “认识米 用米量” 教案设计 人教版 二年级 数学教学 小学 教学目标
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用米量和收集次数对香米香气成分及含量的影响 被引量:4
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作者 朱旗 黄怀生 +2 位作者 李拥军 周文 毛清黎 《湖南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第3期305-308,共4页
为了解用米量和香气收集次数对香米香气成分及含量的影响,采用同时蒸馏萃取法(SDE)进行了研究.结果表明,增加用米量和香气收集次数均能提高香米香气成分的相对含量,当用米量由100g增加为200和300g时,其香气相对含量增加了16.27%和24.37%... 为了解用米量和香气收集次数对香米香气成分及含量的影响,采用同时蒸馏萃取法(SDE)进行了研究.结果表明,增加用米量和香气收集次数均能提高香米香气成分的相对含量,当用米量由100g增加为200和300g时,其香气相对含量增加了16.27%和24.37%;当香气收集次数由1次增加至2次,3次和4次时,其香气相对含量分别增加了5.51%,6.08%和6.35%;但不同香气成分增加的趋势和程度不同.采用200g香米1次收集能得到比较完整的香气组分. 展开更多
关键词 香米 同时蒸馏萃取法 香气收集 用米量
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Effects of a New Long-term Controlled-release Fertilizer on Growth and Development and Yield of Summer Maize 被引量:3
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作者 史桂芳 董浩 +4 位作者 毕军 夏光利 朱国梁 牟小翎 孙国波 《Agricultural Science & Technology》 CAS 2016年第10期2300-2302,2307,共4页
[Objective] The aim was to select the optimal amount of controlled-release fertilizer and provide theoretical references for controlled-release fertilizers use in summer maize. [Method] Long-term controlled-release fe... [Objective] The aim was to select the optimal amount of controlled-release fertilizer and provide theoretical references for controlled-release fertilizers use in summer maize. [Method] Long-term controlled-release fertilizers were applied once at sowing summer maize to explore effects on maize growth, yield, economic profits and environment. [Result] Maize yield reduced a little in the treatment group with 60% CRF, and increased in varying degrees in the rest groups in the range of 1.1%-7.4%, and some showed significant differences. [Conclusion] Controlled-release fertilizers can be applied once at the amount of 80% common fertilizer's, with con- sideration of maize yield, nitrogen use rate and economic profits, which is beneficial for summer maize application and promotion in North China. 展开更多
关键词 Long-term controlled release fertilizer Summer maize YIELD Nitrogen fertilizer use rate
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Effects of Controlled-Release Nitrogen on Yield and Nitrogen Use Efficiency of Summer Maize 被引量:1
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作者 李敏 王道中 +4 位作者 郭熙盛 武际 叶寅 王静 韩上 《Agricultural Science & Technology》 CAS 2017年第4期607-610,共4页
The field experiments were conducted in Anhui during 2016 to investigate the effects of controlled-release nitrogen (CRN) rates and mixture of controlled-re- lease nitrogen and conventional nitrogen (CN) on the yi... The field experiments were conducted in Anhui during 2016 to investigate the effects of controlled-release nitrogen (CRN) rates and mixture of controlled-re- lease nitrogen and conventional nitrogen (CN) on the yield and nitrogen efficiency of summer maize. Six treatments included CK (with no application of N), CNIO0% splits (CN), CRFIO0% (CRN1), CRN60%+CN40% (CRN2), CRN85% (CRN3) and CRN70% (CRN4). The results showed proper CRN increased yields and output val- ue. Compared with CN, CRN2 significantly increased by 13.74%, CRN1 increased by 4.84%, and CRN3 was equal to CN. CRN increased yield by grain number per spike of yield components. CRN2 had the highest apparent nitrogen fertilizer recov- ery efficiency and CRN1 was the second, which were significantly higher than CN. Nitrogen agronomic efficiency of CRN2 was significantly higher than CN. Nitrogen physiological efficiency of CRN2 was higher than CN. The partial productivity of CRN1 was higher than that with CN. And the effect of nitrogen fertilizer of CRN2 was the highest, which was increased 758 yuan/hm2. Considering yield, nitrogen use efficiency and economic benefit, applying the mixture of CRN and CN was the most beneficial treatment. CRN1 was the second treatment, and CRN3 didn't reduce yield. 展开更多
关键词 Controlled-release nitrogen Summer maize YIELD Nitrogen use efficiency
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Effect of Seedling Raising Methods on Leaf Photosynthesis and Grain Yield of Mechanically-transplanted Japonica Rice
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作者 赵轶鹏 王友霜 +5 位作者 吴玉玲 胡婷婷 王健康 丁成伟 郭荣良 徐家安 《Agricultural Science & Technology》 CAS 2017年第11期2057-2061,2063,共6页
This study was conducted to investigate the effects of seedling raising modes on photosynthetic charactedsticsand grain yield under wheat straw returning. Four representative cultivars in Huaibei area were selected as... This study was conducted to investigate the effects of seedling raising modes on photosynthetic charactedsticsand grain yield under wheat straw returning. Four representative cultivars in Huaibei area were selected as test materials. By setting potted seedlings and carpet seedlings, the effects of different nursery meth- ods on the photosynthesis of rice at different growth stages in Huaibei area were investigated. Compared with carpet seedlings, the leaf area index of potted seedlings decreased at the maturation stage, but the dry weight of leaf shewed no significant difference.The SPAD of potted seedlings had an increasing trend after transplanting, but the SPAD increased differently according to cultivars. The net photosynthetic rate, stomatal conductance and transpiration rate of the leaves of pot seeding rice were significantly higher than those of carpet seedling rice on the 85^th d after transplanting. However, theintracellular CO2 concentration and water use efficiency of leaves had no significant differences between different 'treatments. The results indicate that the photosynthetic capacity of flag leaves of pot seedling rice is stronger in early and middle stages, but the decay rate of photosynthetic function is slightly faster than carpet seedling rice, which might be the main reason for the rice yield of potted seedlings having no remarkable difference from carpet seedlings. 展开更多
关键词 Seedling raising method Mechanically transplanting Leaf photosynthesis Grain yield
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Effect of Nitrogen Management on Yield and Water Use Efficiency of Rainfed Wheat and Maize in Northwest China 被引量:26
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作者 DANG Ting-Hui CAI Gui-Xin +2 位作者 GUO Sheng-Li HAO Ming-De L. K. HENG 《Pedosphere》 SCIE CAS CSCD 2006年第4期495-504,共10页
A field experiment with four treatments and four replicates in a randomized complete block design was conducted at the Changwu Experimental Station in Changwu County, Shaanxi Province, of Northwest China from 1998 to ... A field experiment with four treatments and four replicates in a randomized complete block design was conducted at the Changwu Experimental Station in Changwu County, Shaanxi Province, of Northwest China from 1998 to 2002. The local cropping sequence of wheat, wheat-beans, maize, and wheat over the 4-year period was adopted. A micro-plot study using ^15N-lahelled fertilizer was carried out to determine the fate of applied N fertilizer in the first year. When N fertilizer was applied wheat (years 1, 2 and 4) and maize (year 3) grain yield increased significantly (P 〈 0.05) (〉 30%), with no significant yield differences in normal rainfall years (Years 1, 2 and 3) for N application at the commonly application rate and at 2/3 of this rate. Grain yield of wheat varied greatly between years, mainly due to variation in annual rainfall. Results of ^15N studies on wheat showed that plants recovered 36.6%-38.4% of the N applied, the N remained in soll (0-40 cm) ranged from 29.2% to 33.6%, and unaccounted-for N was 29.5%-34.2%. The following crop (wheat) recovered 2.1%- 2.8% of the residual N from N applied to the previous wheat crop with recovery generally decreasing in the subsequent three crops (beans, maize and wheat). 展开更多
关键词 wheat MAIZE ^15N studies water use efficiency YIELD
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Effects of Reducing Application Amount of Base Fertilizer and Increasing Application Time of Leaf Fertilizer on Corn Yield 被引量:4
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作者 李蒙蒙 刘朝 《Agricultural Science & Technology》 CAS 2015年第5期947-950,共4页
This study aimed to investigate the effects of reducing application amount of base fertilizer and increasing application time of leaf fertilizer on corn yield so as to find out the most economical fertilization way fo... This study aimed to investigate the effects of reducing application amount of base fertilizer and increasing application time of leaf fertilizer on corn yield so as to find out the most economical fertilization way for corn. On the basis of protecting environment, the economic benefits will be also increased. The results showed that the corn yield was increased with the increase of application amount of base fertilizer, and was also increased with the increase of application time of leaf fertilizer.For each time of spaying of leaf fertilizer, the corn yield was increased 258-592.5kg/hm^2 with increase amplitude ranging from 2.3%-5.6%. 展开更多
关键词 CORN Application amount of base fertilizer Spraying time of leaf fertilizer YIELD Economic benefits
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Design of 60GHz RF Transceiver in CMOS:Challenges and Recent Advances 被引量:2
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作者 LI Lianming NIU Xiaokang +10 位作者 CHEN Linhui CHAI Yuan ZHANG Tao SHI Jun WANG Aili LUO Ying HE Long CHENG Depeng LIU Nan CUI Tiejun YOU Xiaohu 《China Communications》 SCIE CSCD 2014年第6期32-41,共10页
With more scaling, the speed of than 40 years Moore CMOS transistors is around 100 GHz. Such fact makes it possible to realize mm-wave circuits in CMOS. However, with the target of achieving broadband and power-effici... With more scaling, the speed of than 40 years Moore CMOS transistors is around 100 GHz. Such fact makes it possible to realize mm-wave circuits in CMOS. However, with the target of achieving broadband and power-efficient operation, 60 GHz CMOS RF transceiver faces severe challenges. After reviewing the technology issues, regarding the 60 GHz applications, this paper discusses design challenges both from the system and the building block levels, and also presents some simulated or measured circuits results. 展开更多
关键词 TRANSCEIVER low noise amplifier MIXER power amplifier CMOS
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Exploration on the Regularity of Nitrogen Requirement of Zhoumai 22 in the Condition of Yield Increase of Wheat-maize Integration
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作者 邢永锋 李银平 +3 位作者 方思霞 穆向华 卢青梅 李新平 《Agricultural Science & Technology》 CAS 2015年第7期1421-1424,1428,共5页
[Objective] In this study, the aim was to explore the annual dosage and allocation proportion of nitrogenous fertilizer for Zhoumai 22 in the condition of wheat-maize integration. [Method] The rules of growth and yiel... [Objective] In this study, the aim was to explore the annual dosage and allocation proportion of nitrogenous fertilizer for Zhoumai 22 in the condition of wheat-maize integration. [Method] The rules of growth and yield variation of Zhoumai 22 under different dosages of nitrogenous fertilizer and different distribution ratios were studied. [Result] With the increase of nitrogenous fertilizer application and distribution rate from maize to wheat, the physiological indexes of Zhoumai 22 population showed an increasing trend, while the yield presented the variation trend of increasing firstly and decreasing then. [Conclusion] Annual amount of nitrogenous fertilizer of 600 kg/hm2 and the distribution ratio of 5:5 in the condition of wheat- maize integration was beneficial to the high yield of the whole year's crops and Zhoumai 22. 展开更多
关键词 Wheat-maize Nitrogen application Physiological characteristics Yield
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Promotion of Safe Winemaking Practices Using Quantity Comparison and Methanol-reduction Process for Rice Wine and Whisky
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作者 Wachira Singkong Boonyakrit Rattanapun Kritsada Kaweewong 《Journal of Agricultural Science and Technology(B)》 2012年第4期448-454,共7页
Research was conducted to determine the quantity of methanol in liquor locally produced in nine different areas of Kamphaengphet province, Thailand. All samples were investigated for methanol content and, while quanti... Research was conducted to determine the quantity of methanol in liquor locally produced in nine different areas of Kamphaengphet province, Thailand. All samples were investigated for methanol content and, while quantities varied depending on the fermentation process, the amounts of methanol determined were statistically significant. The results showed a clear trend of increasing amounts of methanol; the longer it was fermented, the higher amount of methanol it gained. The appropriate distillation temperature was at 85 ℃ examined from a fermented sample which had the highest level of methanol. As a part of this research, a workshop was conducted for distillers on skill development and knowledge promotion for rice wine, rice whisky and safe wine manufacturer. This included a campaign to promote safer rice wine distillation process wherein alcohol content does not exceed 15%. An evaluation at the completion of the workshop indicated that the participants had gained knowledge and understanding, satisfaction, and knowledge utilization. 展开更多
关键词 ALCOHOL DISTILLATION starter culture knowledge promotion Thailand training.
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Nutrient Recycling Using Human Urine: Potential for Low Input Farming
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作者 Onesimus Semalulu Margaret Azuba +2 位作者 Patrick Makhosi Fred Semyalo Shuaib Lwasa 《Journal of Agricultural Science and Technology(B)》 2012年第8期919-933,共15页
Recycling human urine for farming was assessed in a peri-urban Kyanja parish, Kampala district, and in a rural Migyera parish, Nakasongola district, to demonstrate its potential and develop local use guidelines. Test ... Recycling human urine for farming was assessed in a peri-urban Kyanja parish, Kampala district, and in a rural Migyera parish, Nakasongola district, to demonstrate its potential and develop local use guidelines. Test crops were maize, Nakati (Solanum aethiopicum), kale, spinach, cabbage, tomatoes, egg plants. Urine-water mixtures (0, 10%, 20%, 30% urine) were applied weekly or bi-weekly. At Kyanja, 30% urine weekly gave the highest maize yields. Within 2 months, 10% urine weekly increased Nakati yield from 5,444 to 24,667 kg ha^-1. 20% Urine weekly increased kale yield (7,556 to 16,111 kg ha^-1) and spinach (4,222 to 19,022 kg ha^-1). At Migyera, 10% urine weekly increased cabbage yield (4,975 to 16,113 kg ha^-1) but 30% urine weekly decreased cabbage head-weight by 36%. Weekly applied urine produced heavier cabbage heads than bi-weekly (548 g vs. 427 g, P 〈 0.05). LeafN was higher for weekly than bi-weekly applied urine (3.3% vs. 3.0%), implying more protein in the former than the latter. From this study, the following guidelines are proposed: Kyanja area, maize: apply 30% urine weekly for 8-weeks; Nakati: apply 10% urine weekly for 8-weeks; Kale and spinach: apply 20% urine weekly; For Migyera area, cabbage and spinach: apply 10% urine weekly. Apply urine 15 cm around each plant starting 2-weeks after transplanting. So kale and spinach prolong urine application for continued harvesting. 展开更多
关键词 Human urine ecological sanitation closing the loop organic fertilizers urban agriculture.
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Application of Nano Coating (SiO2) on Textile Products
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作者 Oguz Dogan Remzi Dag 《Journal of Chemistry and Chemical Engineering》 2017年第2期82-85,共4页
Liquid SiO2 solutions produced by silicon-based nano- powder are covered on the fabric surface by using spray method. Fabric surfaces were coated at the room temperature in air with the different spray nozzles. Surfac... Liquid SiO2 solutions produced by silicon-based nano- powder are covered on the fabric surface by using spray method. Fabric surfaces were coated at the room temperature in air with the different spray nozzles. Surface analysis of the coated fabric was performed by using Contact Angle and SEM pictures. According to the Contact Angles measurements, the coated fabric surfaces showed hydrophobic character between 126 and 146 degrees, and the SiO2 particles sticked to the fabric fibers as seen from SEM picture. 展开更多
关键词 SiO2 nano glass nano coating NANOTECHNOLOGY advanced materials and textile products.
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Exploiting Quantum Confinement for Future Solar Cell Application
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作者 M.Y. Sulaiman U.C. Ahamefula K. Sopian Z. Ibarahim M.A. Alghoul M.Y. Othman N. Amin 《Journal of Energy and Power Engineering》 2010年第1期26-34,共9页
Present solar cells are expensive making photovoitaic electricity only attractive whenever there is government incentive. This paper highlights the cost of photovoltaic classified according to first, second and third ... Present solar cells are expensive making photovoitaic electricity only attractive whenever there is government incentive. This paper highlights the cost of photovoltaic classified according to first, second and third generations. The first and second generations make up the current photovoltaic. The reasons for the efficiency limitation of the first and second generation photovoltaic are given. Nanoparticles such as quantum dots have confinement properties that can be exploited to improve solar cell efficiency and help reduce the cost. Quantum effect that support hot electron collection and multiple exciton generation through impact ionization are discussed. These form the basis of the future generation quantum dot solar cell. 展开更多
关键词 Photovoltaic electricity photovoltaic generations efficiency quantum dot solar cell quantum yield multiple exciton generation impact ionization.
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Interaction between Fermions via Mass less Bosons and Massive Particles
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作者 Voicu Dolocan Voicu Octavian Dolocan Andrei Dolocan 《Journal of Physical Science and Application》 2013年第5期332-340,共9页
By using a Hamiltonian based on the coupling through flux lines, we have calculated the interaction energy between two fermions via mass less bosons as well as via massive particles. In the case of interaction via mas... By using a Hamiltonian based on the coupling through flux lines, we have calculated the interaction energy between two fermions via mass less bosons as well as via massive particles. In the case of interaction via mass less bosons we obtain an equivalent expression for the Coulomb's energy on the form cthc/r, where a is the fine structure constant. In the case of the interaction via massive particles we obtain that the interaction energy contains a term building the potential well. Also, we take into account the spin-spin interaction of the nucleons and we show that this interaction modulates the interaction potential through a cosine factor. The obtained results are in a good agreement with experimental data, for example, of deuteron. We have determined the radial functions for the deuteron. 展开更多
关键词 Particle interactions one pion exchange deuteron.
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Joule-Thomson Coefficient for Strongly Interacting Unitary Fermi Gas
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作者 廖恺 陈继胜 李超 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第9期489-494,共6页
The Joule-Thomson effect reflects the interaction among constituent particles of macroscopic system.Forclassical ideal gas,the corresponding Joule-Thomson coefficient is vanishing while it is non-zero for ideal quantu... The Joule-Thomson effect reflects the interaction among constituent particles of macroscopic system.Forclassical ideal gas,the corresponding Joule-Thomson coefficient is vanishing while it is non-zero for ideal quantum gasdue to the quantum degeneracy.In recent years,much attention is paid to the unitary Fermi gas with infinite two-bodyscattering length.According to universal analysis,the thermodynamical law of unitary Fermi gas is similar to that ofnon-interacting ideal gas,which can be explored by the virial theorem P = 2E/3V.Based on previous works,we furtherstudy the unitary Fermi gas properties.The effective chemical potential is introduced to characterize the nonlinear levelscrossing effects in a strongly interacting medium.The changing behavior of the rescaled Joule-Thomson coefficientaccording to temperature manifests a quite different behavior from that for ideal Fermi gas. 展开更多
关键词 unitary Fermi gas effective chemical potential Joule-Thomson coefficient
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Analysis of the Power System from an Electron Beam Accelerator and the Correlation with the Theoretical Dosimetry for Radiation Processing
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作者 Samir Luiz Somessari Elizabeth S. Ribeiro Somessari Carlos Gaia da Silveira Wilson Aparecido Parejo Calvo 《Journal of Physical Science and Application》 2015年第5期356-366,共11页
Dynamitron DC1500/25/04 type EBA (Electron beam accelerator), model JOB 188, was manufactured by IBA Industrial (Radiation Dynamics, Inc.) and installed at IPEN-CNEN/SP, in 1978. The technical specifications of th... Dynamitron DC1500/25/04 type EBA (Electron beam accelerator), model JOB 188, was manufactured by IBA Industrial (Radiation Dynamics, Inc.) and installed at IPEN-CNEN/SP, in 1978. The technical specifications of the EBA are: energy 0.5 to 1.5 MeV; beam current: 0.3 to 25.0 mA; beam scanning: 60 to 120 cm; beam width: 25.4 mm and frequency: 100 Hz. Nowadays, this accelerator has been used for innumerable applications, such as: For sterilization of medical, pharmaceutical and biological products, treatment of industrial and domestic effluents and sludge, preservation and disinfestations of foods and agricultural products. Other important application are lignocellulosic material irradiation as a pre-treatment to produce ethanol bio-fuel, decontamination of pesticide packing, solid residues remediation, organic compounds removal from wastewater, treatment of effluent from petroleum production units, crosslinking of foams, wires and electric cables. Electron accelerator JOB 188 is, also, very important composite and nanocomposite materials and carbon fibers irradiation, irradiated grafting ion-exchange membranes for fuel cells application, natural polymers and multilayer packages irradiation and biodegradable blends production. The energy of the electron beam is calculated as a function of the current in the accelerator high-voltage divisor, taking into account the thickness and density of the material to be irradiated. This energy is calculated considering the electron through the entire material and the distance from the titanium foil window, so that the absorbed doses at the points of entrance and exit are equivalent on the material. The dose is directly proportional to the beam current and the exposure time of the material under the electron beam and inversely proportional to the scan width. The aim of this paper is to analyze the power system parameters of the EBA Dynamitron DC 1500/25/04, such as, voltage and RMS (Root-mean-square) current in the oscillator system, high voltage generator and waveform. For this purpose software developed in the Radiation Technology Center at IPEN/CNEN-SP to simulate the energy efficiency of this industrial accelerator. Finally, it is also targeted to compare theoretical dosimetry using parameters of energy and beam current with data from the accelerator power system. This knowledge and technology will be very useful and essential for the control system upgrade of EBA, mainly Dynamitron DC 1500/25/04 taking into consideration that radiation processing technology for industrial and environmental applications has been developed and used worldwide. 展开更多
关键词 Electron beam accelerator industrial dosimetry radiation processing accelerator power system Dynamitron DC 1500/25/04 accelerator.
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Evaluation of the yield and nitrogen use efficiency of the dominant maize hybrids grown in North and Northeast China 被引量:29
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作者 CHEN FanJun FANG ZenGuo +5 位作者 GAO Qiang YE YouLiang JIA LiangLiang YUAN LiXing MI GuoHua ZHANG FuSuo 《Science China(Life Sciences)》 SCIE CAS 2013年第6期552-560,共9页
Breeding high-yielding and nutrient-efficient cultivars is one strategy to simultaneously resolve the problems of food security,resource shortage,and environmental pollution.However,the potential increased yield and r... Breeding high-yielding and nutrient-efficient cultivars is one strategy to simultaneously resolve the problems of food security,resource shortage,and environmental pollution.However,the potential increased yield and reduction in fertilizer input achievable by using high-yielding and nutrient-efficient cultivars is unclear.In the present study,we evaluated the yield and nitrogen use efficiency(NUE) of 40 commercial maize hybrids at five locations in North and Northeast China in 2008 and 2009.The effect of interaction between genotype and nitrogen(N) input on maize yield was significant when the yield reduction under low-N treatment was 25%-60%.Based on the average yields achieved with high or low N application,the tested cultivars were classified into four types based on their NUE:efficient-efficient(EE) were efficient under both low and high N inputs,high-N efficient(HNE) under only high N input,low-N efficient(LNE) under only low N input,and nonefficient-nonefficient under neither low nor high N inputs.Under high N application,EE and HNE cultivars could potentially increase maize yield by 8%-10% and reduce N input by 16%-21%.Under low N application,LNE cultivars could potentially increase maize yield by 12%.We concluded that breeding for N-efficient cultivars is a feasible strategy to increase maize yield and/or reduce N input. 展开更多
关键词 MAIZE genotypexnitrogen interaction low nitrogen stress nitrogen use efficiency YIELD
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Multiuser-to-multiuser entanglement distribution based on 1550 nm polarization-entangled photons 被引量:10
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作者 Dong-Yang Cao 《Science Bulletin》 SCIE EI CAS CSCD 2015年第12期1128-1132,I0003,共6页
Telecom-band polarization-entangled photon- pair source has been widely used in quantum communi- cation due to its acceptable transmission loss. It is also used in cooperation with wavelength-division multiplexing (... Telecom-band polarization-entangled photon- pair source has been widely used in quantum communi- cation due to its acceptable transmission loss. It is also used in cooperation with wavelength-division multiplexing (WDM) to construct entanglement distributor. However, previous schemes generally are not suitable for multinode scenario. In this paper, we construct a telecom-band po- larization-entangled photon-pair source, and it shows ul- trahigh fidelity and concurrence which are both greater than 90 % (raw data). Moreover, we set up a four-by-four entanglement distributor based on WDM. We check the 16 Clauser-Horne-Shimony-Holt inequalities, which show nonlocality. Lastly, as an example of practical application of this source, we estimate the quantum bit error rates and quantum secret key rates when it is used in quantum key distribution. Furthermore, the transmission of entanglement in long optical fibers is also demonstrated. 展开更多
关键词 Entanglement distribution MULTIUSER Telecom-band
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Improving Yield and Nitrogen Use Efficiency Simultaneously for Maize and Wheat in China: A Review 被引量:61
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作者 MENG Qingfeng YUE Shanchao +2 位作者 HOU Peng CUI Zhenling CHEN Xinping 《Pedosphere》 SCIE CAS CSCD 2016年第2期137-147,共11页
Achieving both high yield and high nitrogen use efficiency (NUE) simultaneously has become a major challenge with increased global demand for food, depletion of natural resources, and deterioration of environment. A... Achieving both high yield and high nitrogen use efficiency (NUE) simultaneously has become a major challenge with increased global demand for food, depletion of natural resources, and deterioration of environment. As the greatest consumers of N fertilizer in the world, Chinese farmers have overused N, and there has been poor synchrony between crop N demand and N supply because of limited understanding of the N uptake-yield relationship. To address this problem, this study evaluated the total and dynamic N requirement for different yield ranges of two major crops (maize and wheat), and suggested improvements to N management strategies. Whole-plant N aboveground uptake requirement per grain yield (Nreq) initially deceased with grain yield improvement and then stagnated, and yet most farmers still believed that more fertilizer and higher grain yield were synonymous. When maize yield increased from 〈 7.5 to 〉 12.0 Mg ha-I, Nreq decreased from 19.8 to 17.0 kg Mg-1 grain. For wheat, it decreased from 27.1 kg Mg-1 grain for grain yield 〈 4.5 Mg ha-1 to 22.7 kg Mg-1 grain for yield 〉 9.0 Mg ha-1. Meanwhile, the percentage of dry matter and N accumulation in the middle-late growing season increased significantly with grain yield, which indicated that N fertilization should be concentrated in the middle-late stage to match crop demand while farmers often applied the majority of N fertilizer either before sowing or during early growth stages. We accordingly developed an integrated soil-crop system management strategy that simultaneously increases both grain yield and NUE. 展开更多
关键词 crop N requirement high yield integrated soil-crop system management N application timing N demand
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