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人工草地土壤碳氮磷含量变化及化学计量特征研究

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草地学报 2024年第3期32卷 827-837页

作者：阿的哈则常涛秦瑞敏魏晶晶苏洪烨胡雪马丽张中华史正晨李珊袁访李宏林周华坤中国科学院西北高原生物研究所青海省恢复生态学重点实验室青海西宁810008 青海师范大学青海西宁810016 青海大学青海西宁810016 中国科学院大学北京100049

人工草地建植是治理三江源地区草地退化最有效的方法之一。本研究以三江源地区不同牧草播种的土壤为研究对象,通过分析土壤中关键养分元素的含量及其比例关系,揭示了土壤养分的可获得性碳、氮、磷元素循环和平衡机制。研究结果显示,人... 详细信息

人工草地建植是治理三江源地区草地退化最有效的方法之一。本研究以三江源地区不同牧草播种的土壤为研究对象,通过分析土壤中关键养分元素的含量及其比例关系,揭示了土壤养分的可获得性碳、氮、磷元素循环和平衡机制。研究结果显示,人工草地土壤有机碳、全氮和全磷含量明显高于退化草地;混播人工草地对土壤养分改善效果优于单播人工草地;进一步的相关性分析表明,土壤C∶N比值受到碳素和氮素限制,土壤C∶P比值受到碳素限制,土壤N∶P比值受到碳素和氮素的限制。综上所述,碳和氮是该地区主要限制养分元素,因此可以适当添加碳氮养分来改善人工草地的土壤质量。研究结果对于三江源地区通过合理牧草混播方式改善土壤质量提供了重要参考依据。

关键词：三江源人工草地碳氮磷化学计量特征

Long-Term Application of Organic Manure and Mineral Fertilizer on N_2O and CO_2 Emissions in a red Soil from Cultivated Maize-Wheat rotation in China

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Agricultural Sciences in China 2011年第11期10卷 1748-1757页

作者： ZhaI Li-mei L1u Hong-bin ZhaNG Ji-zong HuANG Jing WANG Bo-ren Key Laboratory of Nonpoint Pollution Control Ministry of Agriculture~Institute of Agricultural Resources and Regional Planning ChineseAcademy of Agricultural Sciences Beijing 100081 P.R.China

A long-term field experiment was established to determine the influence of mineral fertilizer and organic manure on soil fertility. A tract of red soil （Ferralic Cambisol） in Qiyang red Soil Experimental Station （Qiyang County, Hunan Province, China） was fertilized beginning in 1990 and N20 and CO2 were examined during the maize and wheat growth season of 2007-2008. The study involved five treatments： organic manure （NPKM）, fertilizer NPK （NPK）, fertilizer NP （NP）, fertilizer NK （NK）, and control （CK）. Manured soils had higher crop biomass, organic C, and pH than soils receiving the various mineralized fertilizers indicating that long-term application of manures could efficiently prevent red soil acidification and increase crop productivity. The application of manures and fertilizers at a rate of 300 kg N ha-1 yr-1 obviously increased NzO and CO2 emissions from 0.58 kg N20-N ha-~ yr-~ and 10565 kg C ha-~ yr-~ in the CK treatment soil to 3.0l kg N20-N ha-~ yr-~ and 28 663 kg C ha-~ yr-I in the NPKM treatment. There were also obvious different effects on N20 and CO2 emissions between applying fertilizer and manure. More N20 and CO2 released during the 184-d maize growing season than the 125- d wheat growth season in the manure fertilized soils but not in mineral fertilizer treatments. N20 emission was significantly affected by soil moisture only during the wheat growing season, and CO2 emission was affected by soil temperature only in CK and NP treatment during the wheat and maize growing season. In sum, this study indicates the application of organic manure may be a preferred strategy for maintaining red emissions than treatments only with mineral fertilizer. soil productivity, but may result in greater N20 and CO2

关键词： red soil N fertilizer organic manure temperature WFPS

围封和施肥对高寒草甸群落特征和植被碳氮库的影响

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草业学报 2024年第4期33卷 1-11页

作者：秦瑞敏程思佳马丽张中华魏晶晶苏洪烨史正晨常涛胡雪阿的哈则袁访李珊周华坤中国科学院西北高原生物研究所青海省恢复生态学重点实验室青海西宁810008 中国科学院大学北京100049 青海大学生态环境工程学院青海西宁810016 青海师范大学地理科学学院青海西宁810008

为探究不同恢复措施对退化高寒草甸的影响,研究了不同围封年限(0、4、13年)和长期施肥(N、P)下草甸群落特征和碳氮库的变化。结果表明:1)随着围封年限增加,物种丰富度指数和Shannon-Wiener指数显著降低,Simpson指数和Pielou指数呈先上... 详细信息

为探究不同恢复措施对退化高寒草甸的影响,研究了不同围封年限(0、4、13年)和长期施肥(N、P)下草甸群落特征和碳氮库的变化。结果表明:1)随着围封年限增加,物种丰富度指数和Shannon-Wiener指数显著降低,Simpson指数和Pielou指数呈先上升后下降的特征;长期N和P添加分别显著降低了物种丰富度指数和ShannonWiener指数。2)地上生物量和根系生物量在4和13年围封下均显著增加,且在4年围封时最高,而凋落物生物量则随围封年限增加而逐渐增加;长期施肥对生物量的影响不显著。3)围封后,植被碳和氮储量显著增加,其中地上生物量和根系碳、氮库均在4年围封时最高,凋落物碳、氮库则在13年围封时最高;长期施肥对植被碳储量无显著影响,仅长期N添加显著提高了地上生物量氮库。4)偏最小二乘(PLS)路径模型显示:围封和施肥导致环境因子发生变化,抑制了群落多样性,促进了植物生物量和植被碳库的积累,而植被氮库特征在施肥处理下发生变化。综上,围封整体上抑制了物种多样性,但能够促进群落生产力提高和植被碳氮库增汇;长期N添加对物种多样性和植被碳库无显著正效应,但促进了植被氮库增汇。

关键词：围栏封育长期施肥群落特征植被碳氮库高寒草甸

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Geomicrobiological in-situ containment of uranium in subsurface and its long-term stability

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Chinese Journal Of Geochemistry 2006年第B08期25卷 110-111页

作者： Won-Kyoung ha Jong-un Lee Department of Civil Geosystem and Environmental Engineering Chonnam National University Gwangju 500-757 KOREA

High-fidelity mode scaling via topologicaloptimized on-chip metalens for compact photonic interconnection

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Light(Advanced Manufacturing) 2023年第3期4卷 222-232页

作者： Yingli ha Lijun Wang Yinghui Guo Mingbo Pu Fang Zou Xiong Li Yulong Fan Xiaoliang Ma Xiangang Luo State Key Laboratory of Optical Technologies on Nano-Fabrication and Micro-Engineering Institute of Optics and ElectronicsChinese Academy of SciencesChengdu 610209China research Center on Vector Optical Fields Institute of Optics and ElectronicsChinese Academy of SciencesChengdu 610209China School of Optoelectronics University of Chinese Academy of SciencesBeijing 100049China Tianfu Xinglong Lake Laboratory Chengdu 610299China

Photonic integrated circuits(PICs)have attracted significant interest in communication,computation,and biomedical ***,most rely on highly integrated PICs devices,which require a low-loss and high-integration guided wave *** to the various dimensions of different integrated photonic devices,their interconnections typically require waveguide *** a waveguide taper can overcome the width mismatch of different devices,its inherent tapering width typically results in a long length,which fundamentally limits the efficient interconnection between devices with a high scaling ratio over a short ***,we proposed a highly integrated on-chip metalens that enables optical interconnections between devices with high width-scaling ratios by embedding a free-form metasurface in a silicon-on-insulator *** special geometric features endow the designed metalens with high coupling efficiency and high *** device has a footprint of only 2.35μm in the longitudinal direction and numerical aperture of 2.03,enabling beam focusing and collimation of less than 10μm between devices with width-scaling ratio of *** the fundamental transverse electric field(TE0)mode,the relative transmittance is as high as 96%for forward incidence(from wide to narrow waveguides),whereas the metalens can realize wavefront shaping for backward incidence,which can be used in optical phase *** study provides new ideas for optical interconnect design and wavefront shaping in high-integration *** design approach has potential applications in directional radiators,LiDAr,on-chip optical information processing,analogue computing,and imaging.

关键词： On-chip metalens Inverse design Phase collimate Photonic integrated circuits

Transverse Flux Induction Coil for uniform Bar Heating Excluding Edge

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Journal of Iron and Steel research International 2012年第S2期19卷 754-757页

作者： PArK Jong-Soo BAE Jin-Su CHO un-Kwan ha Tae-Jong KIM Goo-Hwa Process Engineering Design research Group Engineering Research Center

This work particularly focuses on compensating Joule heat in under-heated areas occurred when thin steel bar is(<20 mm)heated by transverse flux induction heater(TFIH).The under-heated areas take place in range of 50~... 详细信息

This work particularly focuses on compensating Joule heat in under-heated areas occurred when thin steel bar is(ransverse flux induction heater(TFIH).The under-heated areas take place in range of 50~150 mm from the both edges,so Transverse Flux Induction Coil(TFIC)including a magnetic core is proposed and optimized to supplement this *** solutions on the electromagnetic field are obtained numerically by commercial code MAXWELL 3D software from ANSYS *** then,verified experimentally by pilot-scale tests,in which the TFIH was manufactured with a nominal power of 100 kW at a fundamental frequency of 1 ***,TFIC having geometrically the optimized magnetic core made the heating pattern u-shaped,so could supply a desirable temperature profile for the rolling process.

关键词： Transverse Flux Induction heating(TFIH) induction coil magnetic core uniform heating

Heparin improves organ microcirculatory disturbances in caerulein-induced acute pancreatitis in rats

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World Journal of Gastroenterology 2004年第17期10卷 2553-2556页

作者： Marek Dobosz Lucjanna Mionskowska Stanislaw ha■ Sebastian Dobrowolski Dariusz Dymecki Zdzislaw Wajda Department of General and Gastroenterological Surgery St.Vincent a'Paulo HospitalGdyniaPoland Department of General Transplant and Endocrine SurgeryMedical University of Gda■skPoland

AIM:Microcirculatory disturbances are important early pathophysiological events in various organs during acute *** aim of the study was to evaluate changes in microperfusion of the pancreas,liver,kidney,stomach, colon,skeletal muscle,and to investigate the influence of heparin on the organ microcirculation in caerulein-induced experimental acute pancreatitis. METHODS:Acute pancreatitis was induced by 4 intraperitoneal injections of caerulein(Cn)(15 μg/kg).The organ microcirculation was measured by laser Doppler *** interleukin 6 and hematocrit levels were analysed. rESuLTS:Acute pancreatitis resulted in a significant drop of microperfusion in all examined *** administration(2×2.5 mg/kg)improved the microcirculation in pancreas(36.9±4% vs 75.9±10%),liver(56.6±6% vs 75.2±16%),kidney (45.1±6% vs 79.3±5%),stomach (65.2±8% vs 78.1±19%),colon(69.8±6% vs 102.5±19%), and skeletal muscle (59.2±6% vs 77.9±13%).Heparin treatment lowered IL-6(359.0±66 u/mL vs 288.5±58 u/mL) and hematocrit level(53±4% vs 46±3%). CONCLuSION:Heparin administration has a positive influence on organ microcirculatory disturbances accompanying experimental Cn-induced acute pancreatitis.

关键词： Acute Disease Animals Anticoagulants Caerulein Hematocrit Heparin Male Microcirculation Pancreas Pancreatitis rats rats, Wistar research Support, Non-u.S. Gov't Splanchnic Circulation

The effects of anthocyanin extracted from black soybean on benign prostatic hyperplasia-induced rat model

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The effects of anthocyanin extracted from black soybean on b...

HHr PrOFILES PrOCESSING TECHNIQuES FOr LFMCW MILLIMETEr WAVE rADAr

第十七届全国泌尿外科学术会议

作者： Sae Woong Kim Hoon Jang u-Syn ha Su Jin Kim Byung Il Yoon Hyuk Jin Cho Sung-Hoo Hong Ji Youl Lee Tae-Kon Hwang Bong Suk Shim The college of Medicine the catholic University of Korea The Department of the urology Ewha Womans University School of MedicineSeoulKorea

Purpose Anthocyanin is a natural plant pigment and potent *** investigated its actions and antioxidant properties on benign prostatic hyperplasia using a rat model. Materials and Methods thirty male rats were divided ...

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HHR PROFILES PROCESSING TECHNIQUES FOR LFMCW MILLIMETER WAVE...