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Pedosphere 2007年第2期17卷 219-228页

作者： ZENG Zhao-Hai chen wen-Xin hu Yue-Gao SUI Xin-hua chen Dan-Ming College of Agronomy and Biotechnology China Agricultural University Beijing 100094 （China） College of Biology/Key Laboratory of Agro-Microbial Resource and Application Ministry of Agriculture China Agricultural University Beijing 100094 （China）

Seventeen Sinorhizobium meliloti strains from seven provinces in China were used to screen highly effective strains for alfalfa cultivar in a greenhouse study and their symbiotic relationship and competitive ability were studied in the field. CCBAU30138 was the most effective strain, as evidenced by increase in dry weights. A field experiment showed that the inoculation of alfalfa with CCBAU30138 resulted in increases of 11.9% and 19.6% of dry matter production and crude protein production, respectively, in forage of monocultured plants. The total dry matter yields of alfalfa and tall fescue in binary culture were increased by 16.3% by inoculation of alfalfa with this strain. These results showed that S. rneliloti strain CCBAU30138 was an effective inoculant both in the greenhouse and in the field. The analysis of randomly amplified polymorphic DNA （RAPD） by polymerase chain reaction （PCR） from nodule extracts showed that the strain CCBAU30138 had high competitiveness in the field. It occupied 47.5% of nodules in alfalfa monoculture and 44.4% of nodules in alfalfa-tall fescue binary culture after 20 weeks of growth. In conclusion, a simple system to select highly effective and competitive symbiotic strains specific to alfalfa was established. Using this system, a *** suitable for the alfalfa cultivar ‘Vector＇ grown in Wuqiao County of Hebei Province was obtained.

关键词： alfalfa inoculant selection Sinorhizobium meliloti tall fescue

Wave effect of gravitational waves intersected with a microlens field II:An adaptive hierarchical tree algorithm and population study

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 237-250页

作者： Xikai Shan Guoliang Li Xuechun chen wen Zhao Bin hu Shude Mao Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China Department of Astronomy Tsinghua UniversityBeijing 100084China Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China School of Physics and Astronomy Beijing Normal UniversityBeijing 100875China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory for Researches in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaChinese Academy of SciencesHefei 230026China

The gravitational lensing wave effect generated by a microlensing field embedded in a lens galaxy is an inevitable phenomenon in strong lensed gravitational waves(SLGWs).This effect presents both challenges and opportunities for the detection and appli-cation of ***,investigating this wave effect requires computing a complete diffraction integral over each microlens in the *** is extremely time-consuming due to the large number of microlenses(10^(3)-10^(6)).Therefore,simply adding all the microlenses is ***,the complexity of the time delay surface makes the lens plane resolution a crucial factor in controlling numerical *** this paper,we propose a trapezoid approximation-based adaptive hierarchical tree algo-rithm to meet the challenges of calculation speed and *** find that this algorithm accelerates the calculation by four orders of magnitude compared to the simple adding method and is one order of magnitude faster than the fixed hierarchical tree algorithm proposed for electromagnetic *** importantly,our algorithm ensures controllable numerical errors,increasing confidence in the *** with our previous work(***.66,239511,2023),this paper addresses all numerical issues,including integral convergence,precision,and computational time1).Finally,we conducted a population study on the microlensing wave effect of SLGWs using this algorithm and found that the microlensing wave effect cannot be ignored,especially for Type II SLGWs(from saddle position of the time delay surface)due to their intrinsic geometric structures and their typical intersection with a denser microlensing ***,more than 33%(11%)of SLGWs have a mismatch larger than 1%(3%)compared to the unlensed ***,we found that the mismatch between signal pairs in a doubly imaged GW is generally larger than 10^(−3),and 61%(25%)of signal pairs have a mismatch larger than 1%(3%).Theref

关键词： gravitational lensing diffractional integral algorithm gravitational wave

Minimally invasive approaches for histological diagnosis of anterior mediastinal masses

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Chinese Medical Journal 2007年第8期120卷 675-679页

作者： FANG wen-tao XU Mei-ying chen Gang chen Yong chen wen-hu Department of Thoracic Surgery Shanghai Chest Hospital Shanghai 200030 China Department of Anesthesiology Shanghai Chest Hospital Shanghai 200030 China Department of Pathology Shanghai Chest Hospital Shanghai 200030 China

Background Anterior mediastinal masses include a wide variety of diseases from benign lesions to extremely malignant tumors. Management strategies are highly diverse and depend strongly on the histological diagnosis as well as the extent of the disease. We reported a prospective study comparing the usefulness of core needle biopsy and mini-mediastinotomy under local anesthesia for histological diagnosis in anterior mediastinal masses. Methods Atotal of 40 patients with masses of unknown histology and located either at or near the anterior mediastinum received biopsy prior to treatment. The diagnostic methods were core needle biopsy in 28 patients and biopsy through mini-mediastinotomy under local anesthesia in 15 patients （including 3 patients for whom core needle biopsy failed to yield a definite diagnosis）. Results Histological diagnosis was achieved in 18 of the 28 patients receiving core needle biopsy. Of them, all 4 patients with pleural fibromas and 9 of the 12 patients （75%） with pulmonary mass were diagnosed definitively. In the remaining 12 patients with mediastinal mass, histological diagnosis was achieved in only 5 patients （41.7%）. In contrast, biopsy through a mini-mediastinotomy failed in only 3 patients. In the remaining 12 patients with huge mediastinal masses, who underwent mini-mediastinotomy, a definitive histological diagnosis was reached by pathological and/or immunohistochemical study （diagnostic yield 85.7% in 12 of 14 cases of mediastinal mass, P=0.038 vs core needle biopsy）. For the 9 patients with thymic epithelial tumors, the diagnostic yield was 40% （2 in 5 cases） for core needle biopsy and 83.3% （5 in 6 cases） for mini-mediastinotomy. There was no morbidity in patients receiving mini-mediastinotomy. In the 30 patients with biopsy-proven histological diagnosis, the results contributed to therapeutic decision making in 25 cases （83.3%）.Conclusions Core needle biopsy is effective in the diagnosis of pulmonary and pleural diseases. Yet

关键词： minimally invasive diagnosis mediastinal tumor

Mechanical properties and flow stress constitutive relationship of Ti–6Al–4V alloy with equiaxed microstructure at cryogenic temperatures

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Chinese Journal of Aeronautics 2025年第1期38卷 365-379页

作者： Jingwen hu Xun chen Yashun WANG chen YANG College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China Laboratory of Science and Technology on Integrated Logistics Support National University of Defense TechnologyChangsha 410073China

This paper investigates the uniaxial tensile mechanical properties and flow behavior of Ti-6Al-4V alloys with equiaxed microstructure at cryogenic temperatures ranging from 77 K to298 K and strain rates from 10^(-4)/s to 10^(-2)/*** electron microscopy is utilized to analyze the fracture morphology,aiming to reveal the fracture behavior at various *** applicability of the Zener-Hollomon parameter and the Johnson-Cook model in describing the flow stress of Ti-6Al-4V at cryogenic temperatures is ***,a constitutive relationship modeling method based on the variational recurrent networks is *** test results show a significant increase in the strength of equiaxed Ti-6Al-4V alloy under cryogenic conditions while the plastic deformation process is ***,the fracture analysis indicates that even at 77 K,the fracture process is still dominated by ductile fracture,and brittle fracture does not occur within the range of 77 K to 298 *** fitting results validate the performance of the Zener-Hollomon parameter and the Johnson-Cook model in describing the deformation flow stress of Ti-6Al-4V alloy at cryogenic *** results also indicate that the proposed constitutive relationship modeling method based on the variational recurrent network performs better,making it a potential method for widespread applications.

关键词： Titanium alloys Mechanical properties Cryogenics Fracture testing Flow behavior

Application of Digital Image Monitoring System to Detecting a High Voltage Icing Conductor

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Geo-Spatial Information Science 2009年第1期12卷 61-65页

作者： LI Penghui ZHAO wenguang wen Yinping chen Yong hu Wei School of Civil Engineering and Mechanics Huazhong University of Science and Technology 1037 Luoyu Road Wuhan 430074 China

A real-time system of numeral image manipulation technology is employed to inspect the dynamic displacement of an engineering structure. First, the CCD vidicon aims at the fixed point. The image of the fixed point on the structure is gathered by a picture gathering card. By processing pictures with a self-programmed software, the real-time space coordinate of the cali- bration device can be obtained. Finally, the data is dealt with to get the movement curve, and the dynamic displacement is carried out. The system is applied to the test of a high voltage icing conductor. The result indicates that the dynamic data of the ice shedding conductor includes jumping amplitude, displacement-time curve and attenuation process.

关键词： icing conductor ice-shedding jump dynamic displacement image processing

Analysis and prediction of glacier evolution trend(2020-2100)in Northern Xinjiang

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China Geology 2024年第4期7卷 661-671页

作者： Xi-yong Sun Yang Jiao Qian-li Ma Jing-hui Fan Xiao-min Du Jia-feng Liu Shao-qiang Wang wen-chen hu China Aero Geophysical Survey&Remote Sensing Center for Natural Resources China Geological SurveyMinistry of Natural ResourcesBeijing 100083China Oil and Gas Resources Survey Center of China Geological Survey Beijing 100083China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China China University of Geosciences(Beijing) Beijing 100083China China University of Geosciences Wuhan 430074China

Glaciers,as“solid reservoirs”,are precious resources in arid *** study of glaciers is of great significance to the sustainable development and management of agriculture and the economy in northern *** area of glacier distribution on the 1963 topographic map data,1975 MSS data,2000 ETM data,2008 CBERS-2 data,2014 and 2018 ETM+were collected as secondary *** to the remote sensing survey,the glacier areas in Northern Xinjiang are identified during *** on the evolution of glacier area in the past 55 years,and using two scenarios,the average annual decrease area of a region during the whole 1963-2018 and the period with the minimum reduction area,the glacier areas of Southern Tianshan Mountains,Western Tianshan Mountains,Eastern Tianshan Mountains,the Sawuer Mountains and Altai Mountains in Northern Xinjiang,and the whole northern Xinjiang in 2030,2040,2050,and 2100 are examined and *** 2100,the glacier area in Northern Xinjiang may decrease by 43%-59%.

关键词： Glacial evolution Glacial area Global warm Trend analysis Glacial disappear Environmental change Northern Xinjiang Altai Mountains of Central Asia

Significant changes in the physicochemical properties of BC-containing particles during the cold season in Beijing

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Journal of Environmental Sciences 2025年第5期151卷 667-676页

作者： Shuya hu Linghan Zeng Gang Zhao Shiyi chen Chunsheng Zhao Weilun Zhao Min hu State Key Joint Laboratory of Environmental Simulation and Pollution Control International Joint Research Center for Atmospheric Research(IJRC)College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China Department of Atmospheric and Oceanic Sciences School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science and TechnologyNanjing 210044China

The ambient air quality has improved significantly under strict emission controls in Beijing,China over the last *** carbon(BC),as a short-lived climate forcer in ambient aerosols,profoundly impacts the air quality and *** studies have demonstrated a decline in the mass concentration of *** this study,we characterized the chemical compositions and size distributions of BC-containing particles during the cold season of 2022 in Beijing using state-of-the-art instruments capable of exclusively measuring BCcontaining *** optical properties of BC-containing particles were further calculated based on the Mie ***,we compared the properties of BC-containing particles in 2022 with the results of previous *** results showed that the diameters of BC cores became larger while the coating thickness of BC-containing particles became thinner in *** the coating materials,the mass fraction of nitrate increased obviously,and even replaced organic matter as the dominant component during the peak of the pollution *** in chemical compositions and size distributions resulted in lower mass absorption cross-sections(MAC)of BC-containing particles from 10.5±1.1 m^(2)/g in 2016 to 7.3±0.8 m^(2)/g in 2022,reduced by 30.5%.Our results demonstrate the synergistic benefits of air pollution control in improving air quality and mitigating climate ***,the MAC of BC adopted in climate models should vary with the changing air pollution *** study emphasizes that it is imperative to conduct long-term observations of BC-containing particles to better estimate BC’s climate effects.

关键词： Black carbon Chemical composition Size distribution Light absorption ability

Finite-time H∞ control and energy cost optimization for nonlinear delayed systems through switching analysis and interval matrix method

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Science China(Information Sciences) 2025年

作者： Guici chen huimin ZENG Song Zhu Shiping wen Junhao hu hubei Province Key Laboratory of System Science in Metallurgical Process Wuhan University of Science and Technology School of Mathematics China University of Mining and Technology Centre for Artificial Intelligence University of Technology Sydney School of Mathematics and Statistics South-Central Minzu University

Stability, as one of the most important research directions,has caught the attention of many scholars[1–3]. Simultaneously, in domains such as vessel control and vehicle systems,external disturbances are unavoidable. The research challenge thus emerges:“How can one attain the desired system performance in a finite time while controlling the impact of external disturbances on output variables?”. Finite-time H∞control （H∞FTC） is a salient solution to this problem.

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Enhanced Cd^(2+)removal from aqueous solution using olivine and magnesite combination:New insights into the mechanochemical synergistic effect

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Journal of Environmental Sciences 2025年第1期147卷 714-725页

作者： Xiaofang chen Chao Wang Min chen huimin hu Junwei huang Ting Jiang Qiwu Zhang School of Resources&Environmental Engineering Wuhan University of TechnologyWuhan 430070China State Environmental Protection Key Laboratory of Water Environmental Simulation and Pollution Control South China Institute of Environmental SciencesMinistry of Ecology and EnvironmentGuangzhou 510655China

In this study,an efficient stabilizer material for cadmium(Cd^(2+))treatment was successfully prepared by simply co-milling olivine with *** analyticalmethods including XRD,TEM,SEM and FTIR,combined with theoretical calculations(DFT),were used to investigate mechanochemical interfacial reaction between twominerals,and the reaction mechanism of Cd removal,with ion exchange between Cd^(2+)and Mg^(2+)as the main pathway.A fixation capacity of Cd^(2+)as high as 270.61 mg/g,much higher than that of the pristine minerals and even the individual/physical mixture of milled olivine and magnesite,has been obtained at optimized conditions,with a neutral pH value of the solution after treatment to allow its direct *** as-proposed Mg-based stabilizer with various advantages such as cost benefits,green feature etc.,will boosts the utilization efficiency of naturalminerals over the elaborately prepared adsorbents.

关键词： Olivine Magnesite Interface reaction Mechanochemical activation Cadmium removal

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AP1000多根蒸汽发生器传热管破裂分析

原子能科学技术 2015年第6期49卷 1057-1061页

作者：叶杰蔡伟陈文虎深圳中广核工程设计有限公司上海分公司上海200241

利用RELAP5／MOD3程序对AP1000多根蒸汽发生器传热管破裂事故进行了分析。基于最佳估算方法，分析了1～5根蒸汽发生器传热管破裂的工况。分析结果表明：在大气释放阀可用的情况下，主蒸汽安全阀（MSSV）始终保持关闭状态，从而不会旁通... 详细信息

利用RELAP5／MOD3程序对AP1000多根蒸汽发生器传热管破裂事故进行了分析。基于最佳估算方法，分析了1～5根蒸汽发生器传热管破裂的工况。分析结果表明：在大气释放阀可用的情况下，主蒸汽安全阀（MSSV）始终保持关闭状态，从而不会旁通安全壳。每个工况的堆芯补水箱水位均未出现下降，不会产生自动卸压信号。即使假设MSSV卡开，堆芯也从未出现裸露，仍保持可冷却状态。

关键词： AP1000 RELAP5/MOD3 多根蒸汽发生器传热管破裂蒸汽发生器