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Effects of Long-Term Winter Planted Green Manure on Physical Properties of Reddish Paddy Soil Under a Double-Rice Cropping System

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Journal of Integrative Agriculture 2012年第4期11卷 655-664页

作者： YANG Zeng-ping XU ming-gang ZHENG Sheng-xian nie Jun GAO Ju-sheng LIAO Yu-lin XIE Jian Soil and Fertilizer Institute of Hunan Province Changsha 410125 P.R. China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China College of Resources and Environment Hunan Agricultural University Changsha 410128 P.R.China

Soil physical properties are important indicators of the potential for agricultural *** objective was to evaluate the effects of long-term inputs of green manures on physical properties of a reddish paddy soil（Fe-Typic Hapli-Stagnic Anthrosols） under a double cropping *** common cropping pattern before the study was early-late rice-fallow（winter）.The field treatments included rice-rice-fallow（R-R-WF）,rice-rice-rape（R-R-RP）,rice-rice-Chinese milk vetch（RR-MV）,and rice-rice-ryegrass（R-R-RG）.The rape,Chinese milk vetch and ryegrass were all incorporated as green manures 15 d before early rice transplanting during the following *** soil bulk density in all green manure treatments was significantly reduced compared with the winter fallow *** porosity with green manure applications was significantly higher than that under the winter *** green manure treatments had higher 0.25-5 mm water stable aggregates and aggregates stabilities in the plow layer（0-15 cm depth） compared with the fallow *** mean weight diameter（MWD） and normalized mean weight diameter（NMWD） of aggregates in the green manure treatment were larger than that with the winter *** given green manure retained both a higher water holding capacity in the plow layer soil,and a larger volume of moisture at all matric potentials（-10,-33 and-100 kPa）.We conclude that the management of double-rice fields in southern central China should be encouraged to use green manures along with chemical fertilizers to increase SOC content,improve soil physical properties and soil fertility.

关键词： long-term experiment soil physical property green manure reddish paddy soil

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Growth characteristics of type IIa large single crystal diamond with Ti/Cu as nitrogen getter in FeNi–C system

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Chinese Physics B 2020年第1期29卷 457-462页

作者： ming-ming Guo Shang-Sheng Li Mei-Hua Hu Tai-Chao Su Jun-Zuo Wang Guang-Jin Gao Yue You Yuan nie Henan Key Laboratory of Materials on deep-Earth Engineering School of Materials Science and EngineeringHenan Polytechnic UniversityJiaozuo 454003China Jiaozuo Engineering Technology Research Center of Advanced Functional Materials Preparation under High Pressure Jiaozuo 454003China

High-quality type IIa large diamond crystals are synthesized with Ti/Cu as nitrogen getter doped in an FeNi–C system at temperature ranging from 1230℃to 1380℃and at pressure 5.3–5.9 GPa by temperature gradient *** ratios of Ti/Cu are added to the Fe Ni–C system to investigate the best ratio for high-quality type IIa ***,the different content of nitrogen getter Ti/Cu(Ti:Cu=4:3)is added to this synthesis system to explore the effect on diamond *** macro and micro morphologies of synthesized diamonds with Ti/Cu added,whose nitrogen concentration is determined by Fourier transform infrared(FTIR),are analyzed by optical microscopy(OM)and scanning electron microscopy(SEM),*** is found that the inclusions in the obtained crystals are minimal when the Ti/Cu ratio is 4:***,the temperature interval for diamond growth becomes narrower when using Ti as the nitrogen ***,the lower edge of the synthesis temperature of type IIa diamond is 25℃higher than that of type Ib *** the increase of the content of Ti/Cu(Ti:Cu=4:3),the color of the synthesized crystals changes from yellow and light yellow to *** the Ti/Cu content is 1.7 wt%,the nitrogen concentration of the crystal is less than 1 *** SEM results show that the synthesized crystals are mainly composed by(111)and(100)surfaces,including(311)surface,when the nitrogen getter is added into the synthesis *** the same time,there are triangular pits and dendritic growth stripes on the crystal *** work will contribute to the further research and development of high-quality type IIa diamond.

关键词： high temperature and high pressure temperature gradient method type IIa diamond

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大型民机双作动筒式前轮转弯操纵系统设计与仿真分析

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南京航空航天大学学报 2012年第4期44卷 503-510页

作者：聂青聂宏张明南京航空航天大学机械结构力学及控制国家重点实验室南京210016

为了提高飞机起降性能,当前飞机起落架逐步发展为采用电传操纵技术。而为了满足对低速大转角机动和大转弯力矩的要求,现代大部分大型民机都装配了双作动筒式前轮转弯系统。本文以大型民机的双作动筒式电传前轮转弯操纵系统为研究对象,... 详细信息

为了提高飞机起降性能,当前飞机起落架逐步发展为采用电传操纵技术。而为了满足对低速大转角机动和大转弯力矩的要求,现代大部分大型民机都装配了双作动筒式前轮转弯系统。本文以大型民机的双作动筒式电传前轮转弯操纵系统为研究对象,针对双作动筒式前轮转弯机构设计一种随动转阀式换向阀,以满足其在死点位置时液压源换向的要求;随后基于双作动筒式前轮转弯系统对操纵控制的要求,设计了集手轮低速大角度转弯、脚蹬快速小角度转弯以及减摆功能于一体的飞机前轮操纵电液伺服系统,并建立仿真模型,进行动态仿真分析,以检验系统的各项功能。仿真结果表明,系统能够满足工程使用的要求。

关键词：系统设计动态仿真分析电传操纵大型民机前轮转弯系统飞行器设计

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离子束抛光对单晶硅表面质量影响的分子动力学模拟研究

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原子与分子物理学报 2025年第6期42卷 113-121页

作者：赵仕燕郭海林黄思玲张旭夏超翔王大森聂凤明裴宁李晓静中国兵器科学研究院宁波分院宁波315103

离子束抛光作为一种超精密加工技术,被应用于材料表面抛光的精抛阶段,而其原子量级的去除效果使得它的加工过程与加工效果难以直接观察,因此为了能够从微观尺度研究离子束抛光的加工效果以及加工参数对材料表面粗糙度与表面损伤的影响,... 详细信息

离子束抛光作为一种超精密加工技术,被应用于材料表面抛光的精抛阶段,而其原子量级的去除效果使得它的加工过程与加工效果难以直接观察,因此为了能够从微观尺度研究离子束抛光的加工效果以及加工参数对材料表面粗糙度与表面损伤的影响,提出使用分子动力学模拟的方法研究离子束抛光过程,通过对氩离子轰击单晶硅的仿真模拟,分析加工参数对单晶硅表面粗糙度与晶格损伤的影响规律,指导实际的加工工艺设计.研究发现,在不同加工角度下,离子剂量对于表面粗糙度的影响规律不同,低角度(0°~40°)低剂量以及高角度(>50°)高剂量的加工有助于达到较低的表面粗糙度;随着加工角度的增加,离子束对晶体表面造成的损伤逐渐减少,当加工角度大于40°时能够大幅度减少晶格损伤.模拟结果显示在实际的离子束抛光过程中,为了得到高质量的表面,应该采取高角度高剂量的加工方式以达到既降低材料表面粗糙度又减小对材料表面晶格产生损伤的目的.

关键词：离子束抛光表面质量分子动力学单晶硅加工角度

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Changes in brain-derived neurotrophic factor expression after transplanting microencapsulated sciatic nerve cells of rabbits into injured spinal cord of rats

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Neural Regeneration Research 2007年第10期2卷 582-586页

作者： Wen xue Fu Xiao hua Liu Xiao lin Huang Yao fang Yang Xiang xin Che Wei nie Xiang Hui yong Jiang de ming Liu department of Anatomy Medical CollegeJiujiang UniversityJiujiang332000JiangxiProvinceChina department of Internal Medicine Affiliated HospitalJiujiang UniversityJiujiang332000Jiangxi ProvinceChina department of Anatomy Medical College of Nanchang UniversityNanchang 330006JiangxiProvinceChina

Changes of brain-derived neurotrophic factor （BDNF） expression reflect function of nerve cells; meanwhile, they play a significant role in researching interventions on plerosis of nerve injury. OBJECTIVE： To observe and compare the effects on changes of BDNF expression in rats with spinal cord injury between microencapsulated sciatic nerve cells of rabbits and only transplanting sciatic nerve cells of rabbits. deSIGN： Randomized controlled animal study. SETTING： Medical School of Jiujiang College. MATERIALS： The experiment was carried out in the Medical Science Researching Center, Jiujiang College from May 2004 to May 2006. A total of 90 healthy adult SD rats, weighing 250 - 300 g, of either gender; and 10 rabbits, weighing 2.0 - 2.5 kg, of either gender, were provided by Jiangxi Experimental Animal Center. METHODS： Sciatic nerve tissue of rabbits was separated to make cell suspension, After centrifugation, suspension was mixed with 15 g/L alginate saline solution and ejaculated to 20 mmol/L barium chloride saline solution by double-cavity ejaculator. The obtained cell microcapsules were suspended in saline. Rats were randomly divided into microencapsulated group, only suspension group, and only injured group with 30 animals in each group. After anesthesia, T10 spinous process and vertebra lamina of rats in the former two groups were exposed. Spinal cord tissue in 2-mm length was removed from rats by spinal cord right hemi-section. The gelatin sponges with the size of 2 mm × 2 mm × 2 mm were grafted as filing cage, and absorbed 10 μL microencapsulated sciatic nerve cells of rabbit in the microencapsulated group and 10 μL sciatic nerve cells of rabbits in the only suspension group; respectively. No graft was placed in the only injured group. MAIN OUTCOME MEASURES： On the 1^st, 3^rd, 7^th, 14^th and 28^th days after operation, immunohistochemistry （SABC technique） was used to detect distribution and amount of positive-reactive neurons in BDNF of spinal cord samples wh

关键词： spinal cord injuries transplantation, heterologous nerve growth factors

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Reservoir Characteristics and Controlling Factors of Silurian Lower Kepingtage Formation in Tahe Area, Tarim Basin, NW China

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Journal of Earth Science 2017年第6期28卷 1135-1144页

作者： Ruohan Liu Zaixing Jiang ming Wang Weili Yang Jingxiang Guo minghao Wu Yi Gao Shanyazi Wei Zhihong nie Hong He School of Energy Resources China University of Geosciences Beijing 100083 China Institute of Earth Sciences China University of Geosciences Beijing 100083 China Exploration and Production Research Institute SINOPEC Beijing 100083 China Geophysical-China Oilfield Services Limited Tianjin 300451 China PetroChina Coalbed Methane Company Limited Beijing 100028 China

With the breakthrough of exploration in Well TP16-1, the lower Kepingtage Formation becomes a key target for petroleum exploration of deep clastic reservoir in Tahe area. In this paper we focused on the research of the reservoir characteristics and its controlling factors in two sub-member formations（S1k11 and S1k13）. Based on X-ray diffraction, conventional physical properties data（porosity and permeability） and reservoir storage space data（casting thin section and scanning electron microscope）, we determined that the S1k1 Formation belongs to extra-low porosity and permeability reservoir, although the upper S1k13 Formation shows relative better physical characteristic than the lower S1k11 Formation. The development of storage space in the study area is controlled by sedimentary microfacies, diagenesis process. Reservoirs in S1k1 Formation are mainly located in channel（S1k11 sandstones） and sand flat（S1k13 sandstones）. The sand flat sediments with a more coarse grain size compared with the channel. In diagenesis, compaction is the major controlling factor for reducing the porosity, followed by cementation. Dissolution of diagenesis is the major controlling factor in enhancing the reservoir porosities. Compared with channel（S1k11） sandstones, sand flat sandstones（S1k13） have better reservoir quality for its weaker compaction, cementation and stronger dissolution. On the basis of sedimentary characteristics（grain size and subfacies）, physical property（porosity and permeability） and reservoir storage space, we divide the S1k1 reservoir into three categories（I, II and III）. Type I reservoir is high quality reservoir. It is mainly distributed in the south area of S1k11 and S1k13 reservoir. Type II is moderate reservoir. It is located in the middle of S1k11 reservoir and in the north of S1k13 reservoir. Type III is the poor reservoir. It is only located in the north of S1k11 reservoir.

关键词： reservoir characteristics controlling factors reservoir assessment lower Kepingtage Formation Tahe area Tarim Basin

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Single-cell transcriptomes and runx2b-/- mutants reveal the genetic signatures of intermuscular bone formation in zebrafish

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National Science Review 2022年第11期9卷 97-107页

作者： Chun-Hong nie Shi-ming Wan Yu-Long Chen Ann Huysseune Ya-ming Wu Jia-Jia Zhou Alexandre Wagner Silva Hilsdorf Wei-Min Wang Paul Eckhard Witten Qiang Lin Ze-Xia Gao College of Fisheries Key Lab of Freshwater Animal BreedingMinistry of Agriculture and Rural AffairsKey Lab of Agricultural Animal GeneticsBreeding and Reproduction of Ministry of EducationEngineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt Ministry of Education Huazhong Agricultural University Hubei Hongshan Laboratory CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology South China Sea Institute of Oceanology Innovation Academy of South China Sea Ecology and Environmental Engineering Chinese Academy of Sciences department of Biology Ghent University Unit of Biotechnology University of Mogi das Cruzes Guangdong Laboratory for Lingnan Modern Agriculture

Intermuscular bones(IBs) are mineralized spicules, present in the myosepta of many, but not all, teleost species. IBs are often small and sharp, and they consequently limit how the fish can be processed; the IBs may cause injury or trauma if lodged in consumers’ throats or mouths, and therefore affect the appeal of the fish to many consumers. The development of IBs in teleosts is still not fully understood and the molecular basis of IB development remains to be established. Here, the characteristics of IB tissue are evaluated based on single-cell transcriptomics in wild-type zebrafish. The analysis defined 18 distinct cell *** trajectories showed that IBs are derived from tendons and that a core tendon-osteoblast cell lineage is related to IB formation. In particular, the functions of 10 candidate genes were evaluated via CRISPR-Cas9 mutants. Among those, runx2b-/-mutants completely lost IBs, while swimming performance, growth and bone mineral density were not significantly different from runx2b+/+*** single-cell RNA sequencing(sc RNA-seq) analysis in runx2b-/-and runx2b+/+zebrafish revealed the role of osteoblasts in IB formation. In addition, differentially expressed genes were enriched in the transforming growth factor β/bone morphogenetic protein(TGF-β/BMP) pathway after runx2b deletion. This study provides evidence for the crucial role of runx2b regulation in IB formation. Genetic breeding can target runx2b regulation and generate strains of commercial fish species without IBs, which can improve the safe consumption and economic value of many farmed fish species.

关键词： teleosts zebrafish intermuscular bones scRNA-seq tendon-osteoblast cell lineage runx2b genetic breeding

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Advanced hermetic electronic packaging based on lightweight silicon/aluminum composite produced by powder metallurgy technique

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Rare Metals 2020年第11期39卷 1307-1313页

作者： Yan-Qiang Liu Jian-Zhong Fan Xin-Xiang Hao Shao-Hua Wei Jun-Hui nie Zi-Li Ma ming-Kun Liu Ya-Bao Wang National Engineering and Technology Research Center for Nonferrous Metals Composites General Research Institute for Nonferrous MetalsBeijing100088China

Silicon/aluminum(Si/Al)composite is a kind of lightweight electronic packaging material that received a lot of attention in the past 20 *** this paper,a series of Si/Al composites with lowered coefficient of thermal expansion(CTE)and high thermal conductivity were produced by powder metallurgy(PM).The Si/Al composites are fully dense and have fine Si particles uniquely distributed within pure Al *** 50%Si/Al composites were designed to have strength in the range of 185-290 MPa to meet different demands,while the other properties keep *** toughness of the composites is measured to be 9-10 MPa·m^(1/2).The composites were machined to 50%Si/Al housings and 27%Si/Al *** the hermeticities of housings before and after laser-beam-welding sealing are *** measured leak rate of composites and sealed housings is in magnitude order of 1×10^(-10)and 1×10^(-9)Pa·m^(3)·s^(-1),respectively,suggesting high *** good hermeticity is attributed to the full dense materials,good weldability,and extremely low weld *** present Si/Al composites are expected to be extensively used in highly hermetic electronic packages.

关键词： Si/Al composite Electronic packaging Strength Hermetic Powder metallurgy

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Discussion on establishing monitoring networks for temperature fields of shallow thermal energy in Shandong, China

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Journal of Groundwater Science and Engineering 2019年第1期7卷 86-93页

作者： ZHOU Bo WEI Shan-ming WANG Tao nie Yu-peng WANG Chuan-qi No.801 Hydrogeological Engineering Geological Team of Shandong Bureau of Geological and Mineral Exploration and development

In the recent decade, the construction projects related to shallow geothermal energy engineering have undergone rapid development in Shandong Province. The predominant type of these developments and applications was heat exchange through buried tubes and the main targets were residential and office buildings. However, an overwhelming majority of the completed geothermal heat pump projects lacked monitoring devices so that they were unable to comprehensively reflect the background values for the geothermal fields within the province and few researches were conducted on their influence on the geological environment. In this paper, locations for monitoring shallow geothermal energy and their validity of the monitoring point deployment were studied in view of the development and application status as well as geological background conditions of various projects located in multiple cities providing data support for analyzing the fluctuation trend and influence of large-scale shallow geothermal energy applications on the shallow geothermal and the feasibility and parameter designs of newly built systems in Shandong Province in the future.

关键词： Shallow geothermal energy Geothermal field Monitoring network

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气候变暖下水圈甲烷排放及其微生物学机制

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微生物学报 2020年第9期60卷 1821-1833页

作者：聂明复旦大学生物多样性与生态工程教育部重点实验室上海崇明东滩湿地生态系统国家定位观测研究站上海200438

大气温室气体浓度升高导致的气候变暖已对人类社会可持续发展带来了严重影响。水圈生态系统既是全球最为重要的碳汇之一,也是全球最为重要的甲烷自然排放源。因此,阐明气候变暖背景下水圈甲烷排放格局及其相关微生物调控机制,是认识未... 详细信息

大气温室气体浓度升高导致的气候变暖已对人类社会可持续发展带来了严重影响。水圈生态系统既是全球最为重要的碳汇之一,也是全球最为重要的甲烷自然排放源。因此,阐明气候变暖背景下水圈甲烷排放格局及其相关微生物调控机制,是认识未来地球气候系统演变机理、预测未来全球变化潜在情景的关键命题,也将为如何高效发挥水圈碳汇潜力提供基础理论支撑,更好应对全球气候变化问题。本文主要综述了气候变暖背景下主要水圈生态系统中微生物介导的甲烷排放研究的现状与趋势,介绍了水圈甲烷排放格局及其气候变暖背景下的演变趋势,回顾了气候变暖对甲烷代谢相关微生物群落与功能的复杂调控作用。基于目前的研究现状,未来亟需通过微观机制与宏观过程相结合的途径,并基于生态系统复杂性和气候变暖长期性开展相关研究。同时,建议应加强对海洋等相对薄弱区域的研究。

关键词：气候变暖水圈甲烷微生物

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