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Analysis of Carbon Functional Groups in Mobile Humic Acid and Recalcitrant Calcium Humate Extracted from Eight US Soils

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Pedosphere 2013年第6期23卷 705-716页

作者： he zhong-qi CAO Xiao-Yan MAO Jing-Dong T.OHNO H.M.WALDRIP USDA-ARS Southern Regional Research Center Department of Chemistry and Biochemistry Old Dominion University Department of Plant Soiland Environmental SciencesUniversity of Maine USDA-ARS Conservation and Production Research Laboratory

Solid state 13C nuclear magnetic resonance （NMR） spectroscopy is a common tool to study the structure of soil humic fractions; however, knowledge regarding carbon structural relationships in humic fractions is limited. In this study, mobile humic acid （MHA） and recalcitrant calcium humate （CallA） fractions were extracted from eight soils collected from six US states and representing a variety of soils and ecoregions, characterized by this spectroscopic technique and analyzed for statistical significance at P 〈 0.05. We found that the abundances of COO and N-C=O functional groups in the MHA fractions were negatively correlated to soil sand content, but were positively correlated to silt, total N and soil organic carbon contents. In contrast, the abundances of the COO and N-C=O functional groups were only positively correlated to the content of clay in the CallA fractions, indicating that the two humic fractions were associated with different soil components. The two 13C NMR peaks representing alkyls and OCH3/NCH were negatively correlated to the peaks representing aromatics, aromatic C-O and N-C=O/COO. Comparison of the sets of data from 13C NMR spectroscopy and ultrahigh resolution mass spectrometry revealed that the aromatic components identified by the two methods were highly consistent. The comparison further revealed that protein in MHA was associated with, or bound to, the nonpolar alkyl groups, but a component competitively against （or complementary to） aromatic groups in the MHA composition. These observations provided insight on the internal correlations of the functional groups of soil humic fractions.

关键词： correlation analysis humic substances nuclear magnetic resonance soil organic matter ultrahigh resolution mass spectrometry

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High-Efficiency Dynamic Scanning Strategy for Powder Bed Fusion by Controlling Temperature Field of the heat-Affected Zone

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 203-214页

作者： Xiaokang Huang Xiaoyong Tian qi zhong Shunwen he Cunbao Huo Yi Cao Zhiqiang Tong Dichen Li State Key Laboratory of Manufacturing Systems Engineering Xi’an Jiaotong UniversityXian 710049China

Improvement of fabrication efficiency and part performance was the main challenge for the large-scale powder bed fusion(PBF)*** this study,a dynamic monitoring and feedback system of powder bed temperature field using an infrared thermal imager has been established and integrated into a four-laser PBF equipment with a working area of 2000 mm×2000 *** heat-affected zone(HAZ)temperature field has been controlled by adjusting the scanning speed ***,the relationship among spot size,HAZ temperature,and part performance has been *** fluctuation of the HAZ temperature in four-laser scanning areas was decreased from 30.85℃to 17.41℃.Thus,the consistency of the sintering performance of the produced large component has been *** on the controllable temperature field,a dynamically adjusting strategy for laser spot size was proposed,by which the fabrication efficiency was improved up to 65.38%.The current research results were of great significance to the further industrial applications of large-scale PBF equipment.

关键词： Powder bed fusion Efficiency Large-scale Spot size heat-affected zone(HAZ)

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Two ABCI family transporters,OsABCI15 and OsABCI16,are involved in grain-filling in rice

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Journal of Genetics and Genomics 2024年第5期51卷 492-506页

作者： Bin Ma Xiubiao Cao Xiaoyuan Li zhong Bian qi-qi Zhang Zijun Fang Jiyun Liu Qun Li qiaoquan Liu Lin Zhang Zuhua he Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/zhongshan Biological Breeding Laboratory/Key Laboratory of Plant Functional Genomics of the Ministry of Education/Jiangsu Key Laboratory of Crop Genetics and Physiology Agricultural College of Yangzhou UniversityYangzhouJiangsu 225009China Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops Jiangsu Key Laboratory of Crop Genetics and PhysiologyYangzhou UniversityYangzhouJiangsu 225009China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology&EcologyChinese Academy of SciencesShanghai 200032China Institute of Biotechnology Hangzhou Academy of Agricultural SciencesHangzhouZhejiang 310024China Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of Education Yangzhou UniversityYangzhouJiangsu 225009China

Seed development is critical for plant reproduction and crop yield,with panicle seed-setting rate,grain-filling,and grain weight being key seed characteristics for yield ***,few genes are known to regulate grain ***,we identify two adenosine triphosphate(ATP)-binding cassette(ABC)I-type transporter genes,OsABCI15 and OsABCI16,involved in rice *** genes are highly expressed in developing seeds,and their proteins are localized to the plasma membrane and ***,knockout of OsABCI15 and OsABCI16 results in a significant reduction in seed-setting rate,caused predominantly by the severe empty pericarp phenotype,which differs from the previously reported low seed-setting phenotype resulting from failed *** analysis indicates that OsABCI15 and OsABCI16 participate in ion homeostasis and likely export ions between filial tissues and maternal tissues during grain ***,overexpression of OsABCI15 and OsABCI16 enhances the seed-setting rate and grain yield in transgenic plants and decreases ion accumulation in brown ***,the OsABCI15/16 orthologues in maize exhibit a similar role in kernel development,as demonstrated by their disruption in transgenic ***,ourﬁndings reveal the important roles of two ABC transporters in cereal grain filling,highlighting their value in crop yield improvement.

关键词： ABC transporters Rice Grain filling Ion homeostasis Grain yield

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A study on the simulation of carbon and water fluxes of Dangxiong alpine meadow and its response to climate change

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Atmospheric and Oceanic Science Letters 2024年第5期17卷 22-27页

作者： Lingyun he Lei zhong Yaoming Ma Yuting qi Jie Liu Peizhen Li School of Earth and Space Sciences University of Science and Technology of ChinaHefeiChina CAS Center for Excellence in Comparative Planetology HefeiChina Jiangsu Collaborative Innovation Center for Climate Change NanjingChina Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina College of Atmospheric Sciences Lanzhou UniversityLanzhouChina Qomolangma Atmospheric and Environmental Observation and Research Station TingriChina Kathmandu Center for Research and Education Chinese Academy of Sciences-Tribhuvan UniversityBeijingChina China-Pakistan Joint Research Center on Earth Sciences IslamabadPakistan

The alpine meadow ecosystem accounts for 27%of the total area of the Tibetan Plateau and is also one of the most important vegetation *** Dangxiong alpine meadow ecosystem,located in the south-central part of the Tibetan Plateau,is a typical *** understand the carbon and water fluxes,water use efficiency(WUE),and their responses to future climate change for the alpine meadow ecosystem in the Dangxiong area,two parameter estimation methods,the Model-independent Parameter Estimation(PEST)and the Dynamic Dimensions Search(DDS),were used to optimize the Biome-BGC ***,the gross primary productivity(GPP)and evapotranspiration(ET)were *** results show that the DDS parameter calibration method has a better *** annual GPP and ET show an increasing trend,while the WUE shows a decreasing ***,ET and GPP reach their peaks in July and August,respectively,and WUE shows a“dual-peak”pattern,reaching peaks in May and ***,according to the simulation results for the next nearly 100 years,the ensemble average GPP and ET exhibit a significant increasing trend,and the growth rate under the SSP5–8.5 scenario is greater than that under the SSP2–4.5 *** shows an increasing trend under the SSP2–4.5 scenario and a significant increasing trend under the SSP5–8.5 *** study has important scientific significance for carbon and water cycle prediction and vegetation ecological protection on the Tibetan Plateau.

关键词： Carbon and water flux Water use efficiency Alpine meadow Biome-BGC model Climate change

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Dynamic analysis of tethered defunct satellites with solar panels

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Astrodynamics 2024年第2期8卷 297-309页

作者： Rui qi Yang Zhang heng Jiang Rui zhong School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China School of Aerospace Astronautics Beihang UniversityBeijing 100191China

A precise dynamic model for towing and removing a defunct satellite with solar panels in orbit using a tethered net often has low computational efficiency owing to the complex contact and collision between the net and panels,which is not conducive to *** solve this problem,a“single main tether–multiple subtether”bifurcation structure with beads was employed as the tethered net *** study investigated the dynamics of tethered defunct satellites with solar panels,particularly the behavior of the attitude of the tethered satellite,oscillation of the main tether,and vibration of solar panels under different *** results showed that different attachment configurations of the subtethers and the flexibility of the main tether have an evident impact on the dynamic characteristics of the system.

关键词： space debris flexible solar panels tethered towing Kane’s method dynamics modeling

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Multi-objective optimization of a high speed on/off valve for dynamic performance improvement and volume minimization

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Chinese Journal of Aeronautics 2024年第10期37卷 435-444页

作者： qi zhong Junxian WANG Enguang XU Cheng YU Yanbiao LI College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310023China

Hydraulic circuits with high speed on/off valve(HSV)for servo control have become commonplace in ***,the individual valve that is not volume-optimized results in a large total size of hydraulic control system,diminishing the *** address this issue,the high-precision equivalent reluctance model of the HSV is established by employing an equivalent magnetic circuit,on which the dynamic characteristic of the HSV,as well as the effects of structural parameters on switching behaviour,are *** on this model,multi-objective optimization is adopted to design an HSV with faster dynamic performance and smaller volume,NSGA-II genetic algorithm is applied to obtain the Pareto front of the desired *** assess the impact before and after optimization,an HSV based on the optimized structure is manufactured and *** experimental results show that the optimized HSV reduces 47.1%of its solenoid volume while improving opening and closing dynamic performance by 14.8%and 43.0%respectively,increasing maximum switching frequency by 6.2%,and expanding flow linear control area by 6.7%.These results validate the optimized structure and indicate that the optimization method provided in the paper is beneficial for developing superior HSV.

关键词： High speed on/off valve Dynamic response Volume Multiobjective optimization NSGA-II genetic algorithm

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Study of deep transportation and plugging performance of deformable gel particles in porous media

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Petroleum Science 2024年第2期21卷 962-973页

作者： Wen-Jing Zhao Jing Wang zhong-Yang qi Hui-qing Liu National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China

Deformable gel particles(DGPs) possess the capability of deep profile control and flooding. However, the deep migration behavior and plugging mechanism along their path remain unclear. Breakage, an inevitable phenomenon during particle migration, significantly impacts the deep plugging effect. Due to the complexity of the process, few studies have been conducted on this subject. In this paper, we conducted DGP flow experiments using a physical model of a multi-point sandpack under various injection rates and particle sizes. Particle size and concentration tests were performed at each measurement point to investigate the transportation behavior of particles in the deep part of the reservoir. The residual resistance coefficient and concentration changes along the porous media were combined to analyze the plugging performance of DGPs. Furthermore, the particle breakage along their path was revealed by analyzing the changes in particle size along the way. A mathematical model of breakage and concentration changes along the path was established. The results showed that the passage after breakage is a significant migration behavior of particles in porous media. The particles were reduced to less than half of their initial size at the front of the porous media. Breakage is an essential reason for the continuous decreases in particle concentration, size, and residual resistance coefficient. However, the particles can remain in porous media after breakage and play a significant role in deep plugging. Higher injection rates or larger particle sizes resulted in faster breakage along the injection direction, higher degrees of breakage, and faster decreases in residual resistance coefficient along the path. These conditions also led to a weaker deep plugging ability. Smaller particles were more evenly retained along the path, but more particles flowed out of the porous media, resulting in a poor deep plugging effect. The particle size is a function of particle size before inject

关键词： Physical simulation Deformable gel particle Breakage Particle size Residual resistance coefficient

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A STUDY ON The MECHANISM AND CHARACTEROF The INDUSTRIALAND SPATIAL TRANSFERENCE OF FDI IN CHINA

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Chinese Geographical Science 2001年第1期11卷 1-10页

作者： LI Guo-ping, YANG Kai-zhong, he qi-chun, SUN Tie-shan (Department of Urban and Environmental Sciences, Peking University, Beijing 100871, P. R. China) Department of Urban and Environmental Sciences Peking University Beijing P. R. China

In the last two decades, China has become one of the areas that have the greatest potential in industrial production, thus it has ranked second only to USA in the flow of international capital. By the end of 1998, the real value of FDI (Foreign Direct Investment) in China has utilized has added up to $268.1 billion. The big flow of FDI has not only promoted the development of social economy, but also worsened the existing regional difference by choosing spatial location. Under this circumstance, China’s economy faces new restrictions and opportunities while adjusting its regional structure and industrial structure. So it is more and more important for us how to seize the opportunity, to seek the regularity of FDI in choosing location from the aspect of space, to set up relevant strategy to direct FDI at inland regions (areas deficient of capital), and to make appropriate policies, esp. the industrial and regional policies so as for FDI to exert positive influence and avoid negative influence on China and its regional economy and society. Based on the latest domestic and overseas materials and data of the FDI in China, combining with the investigation of the enterprises, this paper has systematically revealed the progress of development of the FDI in China and the developing conditions of the main enterprises directly invested by foreign capital since the reform and opening-up in China. The characters of FDI such as spatial concentration, transference as time goes on, change of the technical content and up-gradation of industrial structure and their forming mechanism have been studied. Then the basic conclusions have been made as follows. Firstly, FDI has been highly concentrated in space. But as time goes by, it has been transferring from coastal regions to inland ones, from big cities to their surrounding districts, and the degree of concentration is decreasing. Secondly, the technical content of the invested projects has gradually increased and the up-gradation of

关键词： FDI in China industrial transference spatial transference character mechanism

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Efficacy and safety of a neurointerventional operation robotic assistance system in cerebral angiography

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Stroke & Vascular Neurology 2024年第3期9卷 243-251,I0210-I0240页

作者： he Liu Conghui Li Shaohua Ren Tong Li Hongliang zhong Jianwen Jia Hongchao Yang Yi qi Junqiang Feng Youxiang Li Yang Wang Department of Neurosurgery Beijing Chao-Yang HospitalCapital Medical UniversityBeijingChina Department of Neurosurgery Hebei Medical University First Affiliated HospitalShijiazhuangHebeiChina Department of Neurosurgery Shanxi Provincial People’s HospitalShanxiTaiyuanChina Department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijingChina

Background At present,neurointerventional surgery requires angiographers to perform operations in the digital subtraction angiography(DSA)*** radiation and chronic joint damage are still unavoidable for ***,we researched and developed a neurointerventional robot-assisted system,which is operated by angiographers in an operating room outside the DSA *** have conducted a prospective,multicentre,randomised controlled trial to evaluate the safety and efficacy of a robot-assisted system in human cerebral *** the future,this research will provide a platform for the research and development of an intelligent surgical system and bring revolutionary progress in neurointerventional *** From December 2020 to December 2021,260 patients were enrolled from three medical centres,who were randomly and equally divided into a robot-assisted system group and a clinical routine cerebral angiography *** success rate of angiography,the rate of the catheter reaching the target vessel,the operation time,X-ray radiation exposure and the incidence of related adverse events were compared between the two *** A total of 257 patients completed this trial;baseline characteristics of the two groups did not differ *** success rate of angiography in both the control group and the experimental group was 100%.The rate of the catheter reaching the target vessel was 99.23%and 100.00%in the control and experimental groups,*** the control versus experimental groups,the angiographic operation time was 48.59±25.60min versus 47.94±27.49min,respectively;the X-ray radiation dose was 735.01±554.77mGy versus 821.65±705.45mGy,respectively;and the incidence of adverse events was 23.44%versus 22.48%,*** statistical differences were present between the two *** The robot-assisted surgical system is more convenient for cerebral angiography and is as safe and effective as the traditional cerebr

关键词： cerebral operation routine

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Investigating Periodic Dependencies to Improve Short-Term Load Forecasting

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Energy Engineering 2024年第3期121卷 789-806页

作者： Jialin Yu Xiaodi Zhang qi zhong Jian Feng State Grid Zhejiang Jiaxing Electric Power Co. Ltd.Jiaxing314000China State Grid Zhejiang Electric Power Co. Ltd.Hangzhou310000China

With a further increase in energy flexibility for customers,short-term load forecasting is essential to provide benchmarks for economic dispatch and real-time alerts in power *** electrical load series exhibit periodic patterns and share high associations with metrological ***,current studies have merely focused on point-wise models and failed to sufficiently investigate the periodic patterns of load series,which hinders the further improvement of short-term load forecasting ***,this paper improved Autoformer to extract the periodic patterns of load series and learn a representative feature from deep decomposition and *** addition,a novel multi-factor attention mechanism was proposed to handle multi-source metrological and numerical weather prediction data and thus correct the forecasted electrical *** paper also compared the proposed model with various competitive *** the experimental results reveal,the proposed model outperforms the benchmark models and maintains stability on various types of load consumers.

关键词： Load forecasting transformer attention mechanism power grid

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