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Biochemical and microbial properties of rhizospheres under maize/ peanut intercropping

Journal of Integrative Agriculture 2016年第1期15卷 101-110页

作者： LI qi-song Key Laboratory of Biopesticide and Chemical Biology Ministry of Education/College of Life Sciences Fujian Agriculture and Forestry University Fuzhou 350002 P.R.China Agroecological Institute Fujian Agriculture and Forestry University Fuzhou 350002 P.R.China Department of Horticulture Pir Mehr Ali Shah Arid Agriculture University Rawalpindi 46300 Pakistan

Maize/peanut intercropping system shows the significant yield advantage. Soil microbes play major roles in soil nutrient cycling and were affected by intercropping plants. This experiment was carried out to evaluate the changing of rhizosphere microbial community composition, and the relationship between microbial community and soil enzymatic activities, soil nutrients in maize/peanut intercropping system under the following three treatments： maize （Zea mays L.） and peanut （Arachis hypogaea L.） were intercropped without any separation （NS）, by half separation （HS） using a nylon net （50 μm） and complete separation （CS） by using a plastic sheet, respectively. The soil microbial communities were assessed by phospholipid fatty acid （PLFA）. We found that soil available nutrients （available nitrogen （Avail N） and available phosphorus （Avail P）） and enzymatic activities （soil urase and phosphomonoesterase） in both crops were improved in NS and HS treatments as compared to CS. Both bacterial and fungal biomasses in both crops were increased in NS followed by HS. Furthermore, Gram-positive bacteria （G＋） in maize soils were significant higher in NS and HS than CS, while the Gram-negative （G-） was significant higher in peanut soil. The ratio of normal saturated to monounsaturated PLFAs was significantly higher in rhizosphere of peanut under CS treatment than in any other treatments, which is an indicator of nutrient stress. Redundancy analysis and cluster analysis of PLFA showed rhizospheric microbial community of NS and HS of both plants tended to be consistent. The urase and Avail N were higher in NS and HS of both plants and positively correlated with bacteria, fungi （F） and total PLFAs, while negatively correlated with G＋/G- and NS/MS. The findings suggest that belowground interactions in maize/peanut intercropping system play important roles in changing the soil microbial composition and the dominant microbial species, which was closely related with the improving of soil

关键词： maize/peanut intercropping phospholipid fatty acid soil nutrient soil enzymes

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Weakly magnetic field-assisted synthesis of magnetite nano-particles in oxidative co-precipitation

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Particuology 2009年第5期7卷 363-367页

作者： Dawei Hu Yanmin Wang qi song College of Materials Science and Engineering South China University of Technology 510640 Guangzhou China Key Laboratory of Special Functional Materials under Ministry of Education 510640 Guangzhou China

This paper presents experimental results on weakly magnetic field-assisted synthesis of magnetite （Fe3O4） nano-particles in an oxidative co-precipitation method, in comparison to the case without magnetic induction. The XRD results show that a weakly magnetic induction below 220 Gs could accelerate the phase transformation from goethite （α-FeOOH） to magnetite （Fe3O4）, and affect the crystal structure, the particle size/morphology and magnetic response of the magnetite nano-particles synthesized. In addition, a higher concentration of the FeCl2 solution in the synthesis reaction led to finer particles, both with and without magnetic induction.

关键词： Magnetic field Oxidative co-precipitation Nano-particle Magnetite Morphology

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An integrated approach to evaluating the coupling coordination degree between low-carbon development and air quality in Chinese cities

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Advances in Climate Change Research 2021年第5期12卷 710-722页

作者： LIU Tian-Le song qi-Jiao Jiaqi LU qi Ye Division of Public Policy Hong Kong University of Science and TechnologyHong KongChina Institute for Public Policy Hong Kong University of Science and TechnologyHong KongChina School of Humanities and Social Sciences North China Electric Power UniversityBeijing102206China Nelson Institute for Environmental Studies University of Wisconsin–MadisonMadison53706USA Department of Political Science University of Wisconsin–MadisonMadison53706USA School of Public Policy and Management Tsinghua UniversityBeijing100084China

Collaborative governance between ecological environment and climate change is a novel signature in China's policy agenda. However, such coordination remains understudied, especially at the local level. Using the principal component analysis, entropy evaluation methods, and the Coupling Coordination Degree Model (CCDM), we evaluated the level of coordination between carbon and air quality mitigation from 34 low-carbon pilot cities in China. We also illustrated the mechanism and policy formation that leads to different coupling patterns at the local level using three case studies. We found that most pilot cities perform a medium level of coupling coordination between low carbon development and air quality. The result reveals that most low-carbon pilot cities score relatively well in low-carbon development. Further, there is a significant cleavage in air quality between cities in the North and those in the South, indicating pilot cities in the South coordinate better than those in the North. In particular, pilot programs in the Southwest and Southeast coastal region perform well in collaborative governance, while the Beijing−Tianjin−Hebei region is rated poorly because of the gap between air quality and low carbon development. Also, we found that the same low-carbon policy might have heterogeneous effects on different air pollutants and across different regions. The local government should adopt low-carbon development policies that address local level specific environmental and economic conditions to maximize their air pollution mitigation benefits.

关键词： Low-carbon development Air quality Coupling coordination degree model Low carbon pilot city

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Rapid Absolute Determination Platform of Nucleic Acid for Point-of-care Testing

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Chemical Research in Chinese Universities 2015年第4期31卷 519-525页

作者： song Bofan JIN Wei song qi JIN qinhan MU Ying Research Center for Analytical Instrumentation State Key Laboratory of lndustrial Control Technology Zhejiang University Hangzhou 310058 P. R. China

Nowadays nucleic acid tests are promising to be considered as point-of-care testing（POCT）. However, no such devices are currently available that can perform all the functions, including absolute nucleic acid determination, worldwide on-site detection, rapid analysis and real-time results reporting via ubiquitous mobile networks simultaneously with full package and automated means of measurement. In this study, we presented a compact low-cost portable POC automated testing platform with all attributes mentioned above. A disposable self-priming compartmentalization（SPC） microfluidic chip is used to conduct isothermal amplification. The platform also includes a micro-computer controlled heating unit, an inexpensive optical imaging setup, and a mobile device with customized software. It may become a useful tool for the rapid on-site detection of infectious diseases as well as other pathogens.

关键词： Point-of-care testing Microfluidic chip Loop-mediated isothermal amplification Mobile medicine

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ONLINE MODEL AND ACTUATOR FAULT TOLERANT CONTROL FOR AUTONOMOUS MOBILE ROBOT

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Chinese Journal of Mechanical Engineering 2007年第3期20卷 29-33页

作者： song qi JIANG Zhe HAN Jianda Robotics Laboratory Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China Department of Auto-Control Shenyang Institute of Aeronautical Engineering Shenyang 110136 China

A novel fault-tolerant adaptive control methodology against the actuator faults is proposed. The actuator effectiveness factors （AEFs） are introduced to denote the healthy of actuator, and the unscented Kalman filter （UKF） is employed for online estimation of both the motion states and the AEFs of mobile robot. A square root version of the UKF is introduced to improve efficiency and numerical stability. Using the information from the UKF, the reconfigurable controller is designed automatically based on an enhancement inverse dynamic control （IDC） methodology. The experiment on a 3-DOF omni-directional mobile robot is performed, and the effectiveness of the proposed method is demonstrated.

关键词： Unscented Kalman filter Active model Fault tolerance Inverse dynamic control

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A Novel Friction Stir Spot Riveting of Al/Cu Dissimilar Materials

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Acta Metallurgica Sinica(English Letters) 2021年第1期34卷 135-144页

作者： Jinglin Liu qi song Lihui song Shude Ji Mingshen Li Zhen Jia Kang Yang College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China China North Industries Corp. Beijing 100053China

In order to eliminate the disadvantages of the keyhole in conventional friction stir spot welding joint and attain the highstrength lap joint of Al/Cu dissimilar metals,a novel welding technique,named as friction stir spot riveting(FSSR),was proposed.A pinless tool and an extra filling stud were *** Al/Cu spot joints without keyhole defect were achieved by the FSSR.A Cu anchor-like structure was formed,which greatly increased the mechanical interlocking between the upper Al sheet and lower Cu *** thin intermetallic compounds containing CuAl2 and CuAl at the Al/Cu interface strengthened the joining interface between the Al sheet and the Cu *** rotating velocity increased frictional heat and plastic deformation and then eliminated the interfacial joining *** FSSR joint with the maximum tensile shear load of 3.50 kN was achieved at a rotating velocity of 1800 rpm and a dwell time of 20 s,whose fracture path passed through the softened region of upper Al *** summary,the novel FSSR technique has the advantages of strong mechanical interlocking and metallurgical bonding between dissimilar materials,thereby attaining the high-strength spot joint.

关键词： Al/Cu dissimilar materials Friction stir spot riveting Intermetallic compounds Microstructures Tensile shear strength

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Regulation of Stamen Development by Coordinated Actions of Jasmonate, Auxin, and Gibberellin in Arabidopsis

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Molecular Plant 2013年第4期6卷 1065-1073页

作者： Susheng song Tiancong qi Huang Huang Daoxin Xie Tsinghua-Peking Center for Life Sciences MOE Key Laboratory of Bioinformatics School of Life Sciences Tsinghua University Beijing 100084 China

Proper stamen development is essential for plants to achieve their life cycles. Defects in stamen development will cause male sterility. A vast array of research efforts have been made to understand stamen developmental processes and reg- ulatory mechanisms over the past decades. It is so far reported that phytohormones, including jasmonate, auxin, gibberellin, brassinosteroid, and cytokinin, play essential roles in regulation of stamen development. This review will briefly summarize the molecular basis for coordinated regulation of stamen development by jasmonate, auxin, and gibberellin in Arabidopsis.

关键词： stamen jasmonate gibberellin auxin.

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Research on Adaptive TSSA-HKRVM Model for Regression Prediction of Crane Load Spectrum

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Computer Modeling in Engineering & Sciences 2023年第9期136卷 2345-2370页

作者： Dong qing qi song Shuangyun Huang Gening Xu College of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuan030024China Zhuzhou Tianqiao Crane Co. Ltd.Zhuzhou412001China

For the randomness of crane working load leading to the decrease of load spectrum prediction accuracy with time,an adaptive TSSA-HKRVM model for crane load spectrum regression prediction is *** heterogeneous kernel relevance vector machine model(HKRVM)with comprehensive expression ability is established using the complementary advantages of various kernel *** combination strategy consisting of refraction reverse learning,golden sine,and Cauchy mutation+logistic chaotic perturbation is introduced to form a multi-strategy improved sparrow algorithm(TSSA),thus optimizing the relevant parameters of *** adaptive updatingmechanismof the heterogeneous kernel RVMmodel under themulti-strategy improved sparrow algorithm(TSSA-HKMRVM)is defined by the sliding window design *** on the sample data of the measured load spectrum,the trained adaptive TSSA-HKRVMmodel is employed to complete the prediction of the crane equivalent load *** this method toQD20/10 t×43m×12mgeneral bridge crane,the results show that:compared with other prediction models,although the complexity of the adaptive TSSA-HKRVMmodel is relatively high,the prediction accuracy of the load spectrum under long periods has been effectively improved,and the completeness of the load information during thewhole life cycle is relatively higher,with better applicability.

关键词： Heterogeneous kernel function RVM TSSA adaptive update mechanism equivalent load spectrum

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Scheme of adaptive polarization filtering based on Kalman model

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Journal of Systems Engineering and Electronics 2006年第1期17卷 13-18页

作者： song Lizhong qi Haiming qiao Xiaolin Meng Xiande Inst. of Electronic Engineering Harbin Inst. of Technology Harbin 150001 P. R. China

A new kind of adaptive polarization filtering algorithm in order to suppress the angle cheating interference for the active guidance radar is presented. The polarization characteristic of the interference is dynamically tracked by using Kalman estimator under variable environments with time. The polarization filter parameters are designed according to the polarization characteristic of the interference, and the polarization filtering is finished in the target cell. The system scheme of adaptive polarization filter is studied and the tracking performance of polarization filter and improvement of angle measurement precision are simulated. The research results demonstrate this technology can effectively suppress the angle cheating interference in guidance radar and is feasible in engineering.

关键词： guidance radar polarization adaptive filter Kalman filtering interference suppression.

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Effects of Si and Cr on Complete Decarburization Behavior of High Carbon Steels in Atmosphere of 2 vol.%O2

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Journal of Iron and Steel Research International 2016年第12期23卷 1316-1322页

作者： Yang-bo LIU Wei ZHANG qian TONG qi-song SUN Shougang Research Institute of Technology Beijing 100048China Beijing Key Laboratory of Green Recyclable Process for Iron&Steel Production Technology Beijing 100048China

The effects of chemical compositions, especially silicon and chromium contents, on the complete decarburization behaviors of steels in atmosphere of 2 vol. %O2 and 98 vol. % N2 were investigated by using a simuhaneous thermal analyzer. Complete decarburization was observed at both 750 and 800 ℃ for 60Si2MnA steel, while 750℃ only for 92A steel. For GCr15 steel, no decarburization was found at 750 or 800 ℃, and only partial decarburization was observed at 850 ℃. It indicates that silicon promotes while chromium prevents the complete decarburization of steels in atmosphere with 2 vol. % O2. The main reason is that silicon increases while chromium reduces the equilib rium concentration of ferrite at the interface of ferrite and austenite, which results in the complete decarburization.

关键词： complete deearburization silicon chromium low oxygen concentration oxide scale

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