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Stand establishment,root development and yield of winter wheat as affected by tillage and straw mulch in the water deficit hilly region of southwestern China

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Journal of Integrative Agriculture 2016年第7期15卷 1480-1489页

作者： li Chao-su li Jin-gang TANG Yong-lu wu Xiao-li wu Chun HUANG Gang ZENG Hui Crop Research Institute Sichuan A cademy of Agricultural SciencesChengdu 610066P.R.China College of Agriculture Sichuan Agricultural UniversityWenjiang 611130P.R.China Agricultural Bureau of Jianyang City Jianyang 621700P.R.China

Good crop stand establishment and root system development are essential for optimum grain yield of dryland wheat （Triti-cum aestivumL.）. At present, little is known about the effect of tilage and straw mulch on the root system of wheat under dryland areas in southwestern China. The aim of this study was to evaluate the effect of three tilage treatments （no-til, NT; rotary til, RT; conventional til, CT） and two crop residue management practices （straw mulch, ML; non-straw mulch, NML） on stand establishment, root growth and grain yield of wheat. NT resulted in lower soil cover thickness for the wheat seed, higher number of uncovered seeds, lower percentage of seedling-less ridges and lower tiler density compared to RT and CT; ML resulted in higher tiler density compared to NML. Straw mulching resulted in more soil water content and root length density （RLD） at most of the growth stages and soil depths. The maximum RLD, root surface area density and root dry matter density were obtained under NT. In the topmost 10 cm soil layer, higher RLD values were found under NT than those under RT and CT. There were no signiifcant differences in the yield or yield components of wheat among the tilage treatments in 2011–2012, but NT resulted in a signiifcant higher yield compared to RT and CT in 2012–2013. Grain yield was signiifcantly higher in ML compared to in NML. A strong relationship was observed between the water-use efifciency and the grain yield. Both NT and ML proved beneifcial for wheat in term of maintaining higher tiler density, better soil water status and root growth, leading to a higher grain yield and enhanced water-use efifciency, especialy in a low rainfal year.

关键词： wheat tilage mulch stand establishment yield Triticum aestivum

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Study on the inclusion interactions of berberine hydrochloride and cucurbit[7] by spectrofluorimetry

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Chinese Chemical Letters 2009年第3期20卷 322-325页

作者： Yan Ping li Hao wu li Ming Du Analytical and Testing Center Shanxi Normal University Linfen 041004 PR China

The inclusion interaction between berberine hydrochloride （BRH） and cucurbit[7] （CB[7]） has been studied by spectrofluorimetry. The result showed that CB[7] interaction with BRH to form a stable inclusion complex with an association constant of 9.57 × 10^4 L/mol and the fluorescence intensity of the complex was enhanced in 17 times higher than that of the studied drug itself. Based on the significant enhancement of fluorescence intensity of BRH in inclusion complex, a spetrofluorimetric method with high sensitivity and selectivity was developed for the determination of BRH in aqueous solution. The linear range of the method was 3.2- 2 × 10^3 ng/mL with a detection limit of 1.1 ng/mL. The proposed procedure could be applied successfully to determination of BRH remained in pharmaceutical dosage forms, spiked human plasma and urine with satisfactory results.

关键词： Berberinc hydrochloride Cucurbit Spectrofluorimetry Inclusion interaction

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Influences of the diameter of the balance hole on the flow characteristics in the hub cavity of the centrifugal pump

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Journal of Hydrodynamics 2019年第5期31卷 1060-1068页

作者： Wei Dong wu-li Chu Zai-lun liu College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China School of Power and Energy Northwestern Polytechnical UniversityXi'an 710129China College of Energy and Power Engineering Lanzhou University of TechnologyLanzhou 730050China

The diameter of the impeller balance hole in a centrifugal pump is closely related to axial ***,to select the appropriate diameter of a balance hole is crucial for balancing the axial force of the centrifugal *** the validation of the CFD method and the grids independence study,the characteristics of flow in the hub cavity have been analyzed in 4 cases with different diameters of balance *** leakage rate of the liquid in the hub cavity of the centrifugal pump is calculated and compared with the test *** to the research,when no balance hole exists,the distribution of liquid velocity in the core area of the hub cavity exhibits axial symmetry,and the circumferential velocity component is approximately 0.4 times of the impeller's rotational *** the balance hole exists,the distribution of liquid velocity in the hub cavity does not exhibit axial symmetry,and the circumferential velocity component is larger than 0.4 times of the impeller's rotational *** radial leakage velocity on the turbulent boundary layer of the pump cover will increase with the increasing diameter of the balance hole.

关键词： Centrifugal pump balance hole hub cavity circumferential velocity component radial velocity component

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Indirect determination of cefradine with n-propyl alcohol-ammonium sulfate-water system by extraction-flotation of cuprous thiocyanate

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Chinese Chemical Letters 2008年第5期19卷 565-568页

作者： ling li wu Wei Zhao Quan Min li College of Chemistry and Environmental Science Henan Normal UniversityThe Key Laboratory of Environmental Pollution Control Technology of Henan province Xinxiang 453007 China Henan Radio and Television University Zhengzhou 450008 China

A new method was developed for the determination of cefradine by extraction-flotation of CuSCN. The experiment indicated that in the presence of 0.20 mol/L NaOH the degradation of cefradine took place in water bath at 100 ℃. The thiol group （-SH） of the degradation product could reduce Cu（Ⅱ） to Cu（Ⅰ） for the formation of the emulsion CuSCN in the presence of NH4SCN at pH 4.0. By determining the residual amount of Cu（Ⅱ） in the solution and calculating the flotation yield of Cu（Ⅱ）, the indirect determination of cefradine can be obtained. This method has been applied to determine cefradine in capsules, human serum and urine samples, respectively.

关键词： Cefradine Copper(Ⅱ) n-Propyl alcohol Extraction-flotation

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Formation of macroporous gel morphology by phase separation in the silica sol-gel system containing nonionic surfactant

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Journal of University of Science and Technology Beijing 2005年第6期12卷 564-571页

作者： Junsheng wu Xiaogang li Wei Du Hua Chen Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China

The phase separation and gel formation behavior in an alkoxy-derived silica sol-gel system containing C16EO15 has been investigated. Various gel morphologies similar to other sol-gel systems containing organic additives were obtained by changing the preparation conditions. Micrometer-range interconnected porous gels were obtained by freezing transitional structures of phase separation in the sol-gel process. The dependence of the resulting gel morphology on several important reaction parameters such as the starting composition, reaction temperature and acid catalyst concentration was studied in detail. The experimental results indicate that the gel morphology is mainly determined by the time relation between the onset of phase separation and gel formation.

关键词： silica sol-gel phase separation macroporous gel morphology nonionic surfactant

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Comparison of BSA Release Behavior from Electrospun PLGA and PLGA/Chitosan Membranes

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Chemical Research in Chinese Universities 2011年第4期27卷 708-711页

作者： wu li-li li Xiao-ran li Hua YUAN Xiao-yan Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and Engineering Tianjin University Tianjin 300072 P.R. China

In order to encapsulate and controlled-release bioactive proteins,three fibrous membranes,i.e.,poly（L-lactide-co-glycolide）（PLGA）,hybrid PLGA and chitosan（H-PLGA/CS）,and core/shell PLGA/CS （C-PLGA/CS）,were produced by emulsion electrospinning,co-electrospinning and coaxial electrospinning,*** serum albumin（BSA） was selected as a model *** loading efficiency of BSA in the PLGA membrane was 1.56%,lower than those of H-PLGA/CS（5.98%） and C-PLGA/CS（4.80%）.BSA release profiles from the three membranes showed initial burst releases in the first 7 d and then sustained release for 28 *** releases at the end of the releasing period,28 d,from the above three membranes were nearly 63%,88% and 94%,respectively,indicating that the introduction of chitosan and the core/shell fiber structure could enhance BSA release *** addition,all these electrospun membranes could retain their fibrous morphologies after in vitro release of BSA for 28 d.

关键词： Controlled release Bovine serum albumin Electrospun membrane Poly(L-lactide-co-glycolide) Chitosan

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Dynamic programming methodology for multi-criteria group decision-making under ordinal preferences

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Journal of Systems Engineering and Electronics 2010年第6期21卷 975-980页

作者： wu li Guanqi Guo Chaoyuan Yue Yong Zhao School of Information and Communication Engineering Hunan Institute of Science and Technology Yueyang 414006 E R. China Institute of Systems Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China

A method of minimizing rankings inconsistency is proposed for a decision-making problem with rankings of alternatives given by multiple decision makers according to multiple criteria. For each criteria, at first, the total inconsistency between the rankings of all alternatives for the group and the ones for every decision maker is defined after the decision maker weights in respect to the criteria are considered. Similarly, the total inconsistency between their final rankings for the group and the ones under every criteria is determined after the criteria weights are taken into account. Then two nonlinear integer programming models minimizing respectively the two total inconsistencies above are developed and then transformed to two dynamic programming models to obtain separately the rankings of all alternatives for the group with respect to each criteria and their final rankings. A supplier selection case illustrated the proposed method, and some discussions on the results verified its effectiveness. This work develops a new measurement of ordinal preferences’ inconsistency in multi-criteria group decision-making （MCGDM） and extends the cook-seiford social selection function to MCGDM considering weights of criteria and decision makers and can obtain unique ranking result.

关键词： multi-criteria group decision-making (MCGDM) ordinal preference minimum deviation method dynamic programming Cook-Seiford social selection function.

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Integrated framework for seismic fragility assessment of cable-stayed bridges using deep learning neural networks

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Science China(Technological Sciences) 2023年第2期66卷 406-416页

作者： PANG YuTao YIN PengCheng WANG JianGuo wu li Faculty of Engineering China University of Geosciences(Wuhan)Wuhan 430074China China Railway Siyuan Survey and Design Group Co. Ltd.Wuhan 430074China Department of Civil Geological and Mining EngineeringPolytechnique MontréalMontréal H3C 3A7Canada

The increasing intensity of strong earthquakes has a large impact on the seismic safety of bridges *** the key component in the transportation network,the cable-stayed bridge should cope with the increasing future hazards to improve seismic *** fragility analysis can assist the resilience assessment under different levels of seismic ***,such an analysis is computationally intensive,especially when considering various random *** present paper implemented the deep learning neural networks that are integrated into the performance-based earthquake engineering framework to predict fragility functions and associated resilience index of cable-stayed bridges under seismic hazards to improve the computational efficiency while having sufficient *** the proposed framework,the Latin hypercube sampling was improved with additional uniformity to enhance the training process of the neural *** well-trained neural network was then applied in a probabilistic simulation process to derive different component fragilities of the cable-stayed *** estimated fragility functions were combined with the Monte Carlo simulations to predict system *** proposed integrated framework in this study was demonstrated on an existing single-pylon cable-stayed bridge in *** reveal that this integrated framework yields accurate predictions of fragility functions for the cable-stayed bridge and has reasonable accuracy compared with the conventional methods.

关键词： deep learning neural network cable-stayed bridge fragility analysis uniform design method seismic resilience

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On the convergence and improvement of stochastic normalized gradient descent

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Science China(Information Sciences) 2021年第3期64卷 105-117页

作者： Shen-Yi ZHAO Yin-Peng XIE wu-Jun li National Key Laboratory for Novel Software Technology Department of Computer Science and TechnologyNanjing University

Non-convex models, like deep neural networks, have been widely used in machine learning applications. Training non-convex models is a difficult task owing to the saddle points of models. Recently,stochastic normalized gradient descent(SNGD), which updates the model parameter by a normalized gradient in each iteration, has attracted much attention. Existing results show that SNGD can achieve better performance on escaping saddle points than classical training methods like stochastic gradient descent(SGD).However, none of the existing studies has provided theoretical proof about the convergence of SNGD for non-convex problems. In this paper, we firstly prove the convergence of SNGD for non-convex ***, we prove that SNGD can achieve the same computation complexity as SGD. In addition, based on our convergence proof of SNGD, we find that SNGD needs to adopt a small constant learning rate for convergence guarantee. This makes SNGD do not perform well on training large non-convex models in practice. Hence, we propose a new method, called stagewise SNGD(S-SNGD), to improve the performance of SNGD. Different from SNGD in which a small constant learning rate is necessary for convergence guarantee,S-SNGD can adopt a large initial learning rate and reduce the learning rate by stage. The convergence of S-SNGD can also be theoretically proved for non-convex problems. Empirical results on deep neural networks show that S-SNGD achieves better performance than SNGD in terms of both training loss and test accuracy.

关键词： non-convex problems stochastic normalized gradient descent computation complexity

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Sedimentary Facies of Marine Shale Gas Formations in Southern China： The Lower Silurian Longmaxi Formation in the Southern Sichuan Basin

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Journal of Earth Science 2016年第5期27卷 807-822页

作者： Yizhen li Xingzhi Wang Bin wu Guoqin li Dule Wang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu 610500China Geological Exploration and Development Research Institute CNPC Chuanqing Drilling Engineering Company LimitedChengdu 610051China Chongqing Mineral Resources Development Company limited Chongqing 400060China

Sedimentary facies is an important factor influencing shale gas accumulation. It not only controlls hydrocarbon generation, but also affects reservoir characteristics and distribution. This paper discusses the Lower Silurian Longmaxi Formation in the south of the Sichuan Basin. Outcrop, core, drilling and logging data identify the sedimentary facies of the formation as continental shelf facies, which is divided into two subfacies： an inner shelf and an outer shelf subfacies. These two subfacies can be further divided into seven microfacies： muddy silty shallow shelf, calcareous silty shallow shelf, muddy limy shallow shelf, storm flow, muddy deep shelf, silty muddy deep shelf and contour current microfacies. Vertical and horizontal distribution of microfacies establishes a sedimentation model of the continental shelf facies. Combined with analization or calculation of geochemical, mineralogical, physical and gas-bearing properties of samples, sedimentary microfacies is evaluated using nine parameters： total organic carbon content, effective shale continuous thickness, vitrinite reflectance, kerogen type, mineral components, porosity, permeability, water saturation and gas content. The evaluation revealed that the most favorable facies for shale gas exploration and development are the muddy deep shelf and part of the silty muddy deep shelf microfacies, with TOC more than 2%, siliceous component over 50%, clay less than 30%, porosity more than 3%, water saturation lower than 40%, gas content greater than 2 m3/t. These results provide a theoretical basis for deciston-making on the most promising areas for shale gas exploration in the Sichuan Basin and for marine shale gas exploration and development in South China.

关键词： Sichuan Basin shale gas Longmaxi Formation sedimentary facies continental shelf.

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