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Responses of Agronomic Benefit and Soil quality to Better Management of Nitrogen Fertilizer Application in Greenhouse Vegetable Land

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Pedosphere 2012年第5期22卷 650-660页

作者： JIANG Hui-Min ZHANG Jian-Feng SONG Xiao-Zong LIU Zhao-Hui JIANG Li-Hua YANG Jun-Cheng Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081(China) institute of Agricultural Resources and Environment Shandong Academy of Agricultural SciencesJinan 250100(China)

As a result of intensive greenhouse vegetable production in northern China, the potential risk of nitrogen （N） fertilizer over-applied is increasingly apparent and is threatening ecosystem and the sustainability of food production. An experiment was carried out in Shouguang, Shangdong Province, China to evaluate agronomic benefit and soil quality under different N applications, including the conventional chemical N rate （1000 kg N ha^（-1） season^（-1）, N1）, 70% of N1 （N2）, 70% of N1 ＋ maize straw （N3）, 50% of N1 ＋ maize straw ＋ drip irrigation （N4）, and 0% of N1 （NO）, during two successive growing seasons of autumn-winter （AW） and winter-spring （WS）. The maximum yields for N4 were 1.1 and 1.0 times greater than those for N1 in the AW and WS seasons, respectively. N agronomic efficiency （AEN） and apparent N recovery efficiency （REN） were greatest with the N4. A significant relationship was found between soil NO3-N content and electrical conductivity （EC）（R^2 = 0.61 in the AW season and R^2= 0.29 in the WS season）. Reducing N fertilizer decreased soil NO3-N accumulation （20.9%-37.8% reduction in the AW season and 11.7%-20.1% reduction in the WS season） relative to the accumulation observed for N1 within the 0-100 cm soil layer. Soil urease and invertase activities were not significantly different among N treatments. The N4 treatment would be practical for reducing excess N input and maintaining the sustainability of greenhouse-based intensive vegetable systems in Shouguang.

关键词： maize straw N use efficiency soil enzyme soil NO3-N accumulation tomato yields

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Study on the detection method of holes in composite insulator rods

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High Voltage 2021年第5期6卷 873-880页

作者： Sida Zhang Li Cheng Yunfan Liu Ruijin Liao Tingting Wang Huan Huang School of Electrical Engineering Chongqing UniversityChongqingChina Electric Power Research institute China Southern Power Grid Co.GuangzhouChina Electric Power Research institute Guizhou Power Grid Co.GuiyangChina

The holes in composite insulator rods are a type of quality ***,not all holes can be identified by the dye penetration test according to existing standards and some holes can cause abnormal heating of the composite insulator during ***‐computed tomography is used to study the structure of these *** on the pore structure,the holes are classified as dependent or *** dependent hole is formed by several interconnected adjacent pores and the overlong equivalent penetration path makes it cannot be effectively identified by the standard dye penetration *** the structure of the dependent hole,ethanol gas was used to increase the effectiveness of the dye penetration *** experimental results show that the detection rate of dependent holes is approximately 80%as the ethanol concentration is close to saturation,and the porosity can be inferred based on the number of penetration points.

关键词： composite structure porosity

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Scattering loss and efficiency of the multi-pass mini-slab Nd:YAG ceramic lasers

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Chinese Optics Letters 2011年第2期9卷 45-47页

作者：王岩陈凡王明建徐剑秋 Shanghai institute of Fine Mechanics and Optics Chinese Academy of Science Department of Physics Shanghai Jiao Tong University

Multi-pass mini-slab （MPMS） Nd：YAG ceramic lasers with a single-mode output of 38 W is examined corresponding to an optical conversion efficiency of 47%. Although several characteristics of various ceramic samples are almost similar, such as transmission, emission and absorption spectra, cross section, and thermal conductivity, their optical conversion efficiencies can vary from 5% to 40%. We present a simple technique to on-line measure the influence of scattering loss of ceramic on laser performance. This particular technique provides convenience and accuracy in pre-monitoring ceramic sample quality. Experimental results of the MPMS Nd：YAG ceramic laser agree with evaluations.

关键词： Ceramic materials Conversion efficiency Neodymium

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Sharp Bounds for Symmetric and Asymmetric Diophantine Approximation

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Chinese Annals of Mathematics,Series B 2011年第2期32卷 303-320页

作者： Cornelis KRAAIKAMP Ionica SMEETS Delft University of Technology and Thomas Stieltjes institute for Mathematics EWIDIAMMekelweg 42628 CD DelftNetherlands Universiteit Leiden and Thomas Stieltjes institute for Mathematics Niels Bohrweg 12333 CA LeidenNetherlands

In 2004,Tong found bounds for the approximation quality of a regular continued fraction convergent to a rational number,expressed in bounds for both the previous and next *** authors sharpen his results with a geometric method and give both sharp upper and lower *** asymptotic frequencies that these bounds occur are also calculated.

关键词： Continued fractions Diophantine approximation Upper and lower bounds

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Fidelity of Quantum Teleportation for Single-Mode Squeezed State Light

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Chinese Physics Letters 2005年第12期22卷 3005-3008页

作者：张俊香谢常德彭堃墀 State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Optoelectronics Shanxi University Taiyuan 030006

The fidelity of quantum teleportation of a single-mode squeezed state of light is calculated based on the general theory of quantum-mechanical measurement in the Schrodinger picture. It is shown that the criterion for the nonclassical state teleportation is different from that for coherent state. F = 1/2 is no longer the rigorous boundary between classical and quantum teleportation for a squeezed state of light. When the quantum entanglement of an Einstein-Podolsky-Rosen （EPR） beam used for teleportation and the parameters of the system are given, the fidelity depends on the squeezing of the input squeezed state. The higher the squeezing is, the smaller the fidelity is, and the lower the classical limitation of fidelity is. The dependence of the optimum gain for teleporting a squeezed vacuum state upon the EPR entanglement is also calculated. The results obtained provide important references for designing experimental systems of teleporting a non-classical state and judging the quality of the teleported quantum state.

关键词： PODOLSKY-ROSEN CHANNELS CONTINUOUS-VARIABLES PROBABILISTIC TELEPORTATION ENTANGLED STATE COMMUNICATION COMPUTATION FORMULATION

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Potential benefits of amino acid supplementation for cervid performance and nutritional ecology,with special focus on lysine and methionine:A review

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Animal Nutrition 2022年第4期11卷 391-401页

作者： Veit Ny Tersia Needham Francisco Ceacero Department of Animal Science and Food Processing Faculty of Tropical AgriSciencesCzech University of Life Sciences PragueCzech Republic Department of Cattle Breeding Institute of Animal SciencePragueCzech Republic Food Research institute Prague Czech Republic

Deer farming is a thriving industry for venison,velvet antlers,trophy hunting,and other *** and nutrition are important factors for improving production performance,especially dietary protein and amino acids(AAs),as they are the main components of all *** a few studies on AA supplementation(Lys,Met,Arg)have been performed on cervids,which show positive effects on weight gain,ADG,feed-:gain ratio,plasma AAs,carcass weight,dressing percentage,yield of high-quality muscles,storage of internal fat during winter,DM and CP digestibility,plasma protein-and fat-related metabolite concentrations,antler burr perimeter,weight,length and mineralisation,velvet antler yield,rumen volatile fatty acids,and microbiome *** these effects are relevant for supporting the production of cervids products,from venison to velvet or trophy antlers,as well as their general performance and well-being of captive-bred *** current available information suggests that AA supplementation can be especially interesting for animals fed low protein rations,and growing animals,but should be avoided in high rations and during winter,since it may promote the accumulation of internal *** effects on milk production and the concentrations of different hormones involved in the regulation of the antler cycle should be further explored.

关键词： Antler Deer Feed additive Protein Ruminant Venison

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Robust video denoising with sparse and dense noise modelings

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Science China(Information Sciences) 2018年第1期61卷 270-272页

作者： Guiping SHEN Zhi HAN Xi'ai CHEN Yandong TANG State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of Sciences University of Chinese Academy of Sciences

Videos can be contaminated by noise even when captured by high-quality *** video data has both spatial and temporal redundancies,low rank factorization has been ***,most denoising methods relied on a single statistical distribution to model noise,such as Gaussian distribution[1,2].Ji et al.[3]proposed a low rank matrix completion(LRMC)relying on

关键词： Robust video denoising with sparse and dense noise modelings Figure

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Surface Reactivity in Tropical Highly Weathered Soils and Implications for Rational Soil Management

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Pedosphere 2004年第4期14卷 409-423页

作者： R.MOREAU J.PETARD Research institute for Development(IRD) 911 Avenue AgropolisBP 6450134394 Montpellier Cedex 5(France).Research Institute for Development(IRD)911 Avenue AgropolisBP 6450134394 Montpellier Cedex 5(France).

Highly weathered soils are distributed in the humid and wet-dry tropics, as well as in the humid subtropics. As a result of strong weathering, these soils are characterized by low activity clays, which develop variable surface charge and related specific properties. Surface reactions regarding base exchange and soil acidification, heavy metal sorption and mobility, and phosphorus sorption and availability of the tropical highly weathered soils are reviewed in this *** controlling surface reactivity towards cations and anions, including ion exchange and specific adsorption processes, are discussed with consideration on practical implications for rational management of these soils. Organic matter content and pH value are major basic factors that should be controlled through appropriate agricultural practices, in order to optimise favorable effects of colloid surface properties on soil fertility and environmental quality.

关键词： heavy metal highly weathered soils phosphorus tropical soil management variable charge minerals

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Approaches to establish Q-markers for the quality standards of traditional Chinese medicines

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Acta Pharmaceutica Sinica B 2017年第4期7卷 439-446页

作者： Wenzhi Yang Yibei Zhang Wanying Wu Luqi Huang Dean Guo Changxiao Liu National Engineering Laboratory for Standardization of Traditional Chinese Medicine Shanghai Institute of Materia Medica Research Center for Chinese Medicinal Resources China Academy of Chinese Medical Sciences Research Center for New Drug Evaluation Tianjin Institute of Pharmaceutical Research

Traditional Chinese medicine(TCM) has played a pivotal role in maintaining the health of Chinese people and is now gaining increasing acceptance around the global scope. However, TCM is confronting more and more concerns with respect to its quality. The intrinsic "multicomponent and multitarget" feature of TCM necessitates the establishment of a unique quality and bioactivity evaluation system, which is different from that of the Western medicine. However, TCM is investigated essentially as"herbal medicine" or "natural product", and the pharmacopoeia quality monographs are actually chemicalmarkers-based, which can ensure the consistency only in the assigned chemical markers, but, to some extent, have deviated from the basic TCM theory. A concept of "quality marker"(Q-marker), following the "property-effect-component" theory, is proposed. The establishment of Q-marker integrates multidisciplinary technologies like natural products chemistry, analytical chemistry, bionics, chemometrics,pharmacology, systems biology, and pharmacodynamics, etc. Q-marker-based fingerprint and multicomponent determination conduce to the construction of more scientific quality control system of *** review delineates the background, definition, and properties of Q-marker, and the associated technologies applied for its establishment. Strategies and approaches for establishing Q-marker-based TCM quality control system are presented and highlighted with a few TCM examples.

关键词： Traditional Chinese medicine Q-marker quality control Property-effect-component

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我国黑土粮仓正面临极端水文干旱加剧的威胁

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Science Bulletin 2023年第5期68卷 481-484,M0003,M0004页

作者：刘孟竹郭英张晓龙沈彦军张玉翠裴宏伟闵雷雷王仕琴沈彦俊 CAS-Key Laboratory of Agricultural Water Resources Hebei-Key Laboratory of Water Saving AgricultureCenter for Agricultural Resources ResearchInstitute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050022China School of Advanced Agricultural Science University of Chinese Academy of SciencesBeijing 100049China Hebei Key Laboratory of Water quality Engineering and Comprehensive Utilization of Water Resources Department of Municipal and Environmental EngineeringHebei University of ArchitectureZhangjiakou 075000China

黑土粮仓是中国粮食安全的“压舱石”.近几十年频现的水文干旱对黑土粮仓粮食生产和生态安全造成了极大影响,然而目前该区水文干旱的变化机制仍未被很好地揭示.本研究使用GRACE卫星数据并结合3种机器学习模型,重建了黑土粮仓(主要研究... 详细信息

黑土粮仓是中国粮食安全的“压舱石”.近几十年频现的水文干旱对黑土粮仓粮食生产和生态安全造成了极大影响,然而目前该区水文干旱的变化机制仍未被很好地揭示.本研究使用GRACE卫星数据并结合3种机器学习模型,重建了黑土粮仓(主要研究区为松花江流域)近60年(1960~2020年)的水储量变化并揭示了水文干旱规律.结果显示,尽管观测期内(2002~2020年)水储量在增加(+4 mm/a),但平均水储量仍低于重建时期(1960~2002年)水平.近20年的水文干旱相比于历史时期愈加频繁和极端,最近10年的多雨期甚至也出现了以往少雨期才有的异常水文干旱事件.随着下一个少雨期的到来,未来的极端水文干旱将会进一步加剧,这给当地的农业和生态安全带来了极大威胁.我们呼吁相关管理者重视该地区极端水文干旱事件频发并加剧的现象,及时制定应对预案来保障我国黑土粮仓的生态与粮食安全.

关键词：粮食安全水文干旱生态安全松花江流域粮仓多雨期变化机制黑土

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