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Effects of porous clay ceramic rates on aeration porosity characteristics in a structurally degraded soil under greenhouse vegetable production

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Pedosphere 2021年第4期31卷 606-614页

作者： quanbo yu Meiyan WANG yutian TIAN Xuezheng SHI Xiangwei LI Lingying XU Xinqiao XIE Yijie SHI yuncong ZHU State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) University of Chinese Academy of Sciences Beijing 100049(China) Hongta Tobacco Group Company Limited Yunnan 653100(China)

Soil structure degradation in greenhouse vegetable fields reduces vegetable production. Increasing aeration porosity is the key to ameliorating soil structure degradation. Thus, we tested the effect of a porous material, porous clay ceramic(PLC), on the amelioration of soil structure degradation under greenhouse vegetable production. A 6-month pot experiment was conducted with four PLC application levels based on volume, i.e., 0%(control), 5%(1 P), 10%(2 P), and15%(3 P) using Brassica chinensis as the test plant. At the end of the experiment, soil columns were sampled, and the aeration pore network was reconstructed using X-ray computed tomography(CT). The degree of anisotropy(DA), fractal dimension(FD), connectivity, aeration porosity, pores distribution, and shape of soil aeration pores and plant biomass were determined. The DA, FD, and connectivity did not significantly differ as the PLC application rate ***, aeration porosity significantly linearly increased. The efficiency of PLC at enhancing soil aeration porosity was 0.18% per Mg ha^(-1). The increase in aeration porosity was mainly due to the increase in pores > 2 000 μm, which was characterized by irregular pores. Changes in aeration porosity enhanced the production of B. chinensis. The efficiency of PLC at increasing the plant fresh weight was 0.60%, 3.06%, and 2.12% per 1% application rate of PLC for the 1 P, 2 P, and 3 P treatments, respectively. These results indicated that PLC is a highly efficient soil amendment that improves soil structure degradation by improving soil aeration under greenhouse conditions. Based on vegetable biomass, a 10% application rate of PLC was recommended.

关键词： aeration pore network mineral amendment pore size distribution soil physical property soil structure degradation

低场核磁探测水稻田改蔬菜地土壤水分的相态变化

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农业工程学报 2016年第24期32卷 124-128页

作者：孔超王美艳史学正郭乃嘉于全波土壤与农业可持续发展国家重点实验室(中国科学院南京土壤研究所) 南京210008 中国科学院大学北京100049

为了解水稻土转变为设施蔬菜地后土壤水分的相态变化,该研究在田间土壤调查的基础上,结合低场核磁测氢技术,评价了田间状态的水稻土和不同转化年限设施蔬菜地土壤水分的相态分布情况。结果表明:随着转化时间的延长,耕层土壤大孔隙吸持... 详细信息

为了解水稻土转变为设施蔬菜地后土壤水分的相态变化,该研究在田间土壤调查的基础上,结合低场核磁测氢技术,评价了田间状态的水稻土和不同转化年限设施蔬菜地土壤水分的相态分布情况。结果表明:随着转化时间的延长,耕层土壤大孔隙吸持的自由水比重下降,土壤小孔隙吸持的束缚水比重上升,犁底层土壤水分的相态分布却无明显变化,土壤水分吸持性能在转化时间序列上呈现下降的趋势,但长期施用有机肥可以优化耕层质量,提升土壤大孔隙吸持自由水的能力,改善土壤水分供释性能;水稻土转化为设施蔬菜地土壤2 a后,出现新犁底层,使得原有的耕层土壤变薄,土壤水分吸持性能下降。核磁共振作为一种新的技术手段,可以实现实时、快速、准确地检测土壤水分的相态变化,可为设施农业的可持续管理提供新的技术支持。

关键词：核磁共振土壤水分水稻田蔬菜地 T2谱

Linear-Quadratic Pareto Cooperative Game for Mean-Field Backward Stochastic System

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Journal of Systems Science & Complexity 2024年第3期37卷 947-964页

作者： WANG yu School of Control Science and Engineering Shandong UniversityJinan 250061China

This paper focuses on a Pareto cooperative differential game with a linear mean-field backward stochastic system and a quadratic form cost functional. Based on a weighted sum optimality method, the Pareto game is equivalently converted to an optimal control problem. In the first place,the feedback form of Pareto optimal strategy is derived by virtue of decoupling technology, which is represented by four Riccati equations, a mean-field forward stochastic differential equation(MF-FSDE),and a mean-field backward stochastic differential equation(MF-BSDE). In addition, the corresponding Pareto optimal solution is further obtained. Finally, the author solves a problem in mathematical finance to illustrate the application of the theoretical results.

关键词： Backward stochastic differential equation linear-quadratic control mean-field Pareto optimality

Approximate analytical solutions for threedimensional ascent trajectory of a solid-fuel launch vehicle with time-varying mass flow rate

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Chinese Journal of Aeronautics 2024年第10期37卷 275-293页

作者： Qi yu Wanchun CHEN Wenbin yu School of Astronautics Beihang UniversityBeijing 102206China

In the scenario that a solid-fuel launch vehicle maneuvers in outer space at high angles of attack and sideslip for energy management,Approximate Analytical Solutions(AAS)for the threedimensional(3D)ascent flight states are derived,which are the only solutions capable of considering time-varying Mass Flow Rate(MFR)at *** uneven MFR makes the thrust vary nonlinearly and thus increases the difficulty of the problem *** AAS are derived based on a 3D Generalized Ascent Dynamics Model(GADM)with a normalized mass as the independent *** simplify some highly nonlinear terms in the GADM,several approximate functions are introduced carefully,while the errors of the approximations relative to the original terms are regarded as minor ***,a finite series with positive and negative exponents,called Exponent-Symmetry Series(ESS),is proposed for function approximation to decrease the highest exponent in the AAS so as to reduce computer round-off *** calculate the ESS coefficients,a method of seeking the Optimal Interpolation Points(OIP)is proposed using the leastsquares-approximation *** to the artful design of the approximations,the GADM can be decomposed into two analytically solvable subsystems by a perturbation method,and thus the AAS are obtained ***,to help implement the AAS,two indirect methods for measuring the remaining mass and predicting the burnout time in flight are put forward using information from *** results verify the superiority of the AAS under the condition of time-varying MFR.

关键词： Approximate analytical solutions 3D ascent trajectory Solid-fuel launch vehicle Uneven thrust Energy management

Low-melting mixture solvents: extension of deep eutectic solvents and ionic liquids for broadening green solvents and green chemistry

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Green Chemical Engineering 2024年第4期5卷 409-417页

作者： yu Chen Zhiwu yu MOE Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology Department of ChemistryTsinghua University

Green solvents such as water and ionic liquids(ILs) are pillars of the great mansion of green chemistry and green processing. Initially proposed as a new family of ILs,deep eutectic solvents(DESs) have received fast development in the past two decades. In this contribution,DESs are reviewed critically and the concept is extended to lowmelting mixture solvents(Lo MMSs),which cover all kinds of materials including ionic compounds,molecular compounds,and metals. Six classes of Lo MMSs are proposed as the new classification system and examples are given. Finally,several thermodynamic issues concerning Lo MMSs are discussed. Two new concepts,robustness of Lo MMSs and high-entropy Lo MMSs,are proposed.

关键词： Green solvents Deep eutectic solvents Low transition temperature mixture solvents Phase diagram EGaIn

Topological Stability and Entropy for Certain Set-valued Maps

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Acta Mathematica Sinica,English Series 2024年第4期40卷 962-984页

作者： yu ZHANG yu Jun ZHU School of Mathematical Sciences Xiamen UniversityXiamen 361005P.R.China

In this paper,the dynamics(including shadowing property,expansiveness,topological stability and entropy)of several types of upper semi-continuous set-valued maps are mainly considered from differentiable dynamical systems points of *** is shown that(1)if f is a hyperbolic endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has theε-shadowing property,and moreover,if f is an expanding endomorphism then there exists a C^(1)-neighborhood U of f such that the induced set-valued map F_(f,U)has the Lipschitz shadowing property;(2)when a set-valued map F is generated by finite expanding endomorphisms,it has the shadowing property,and moreover,if the collection of the generators has no coincidence point then F is expansive and hence is topologically stable;(3)if f is an expanding endomorphism then for eachε>0 there exists a C^(1)-neighborhood U of f such that h(F_(f,U,ε))=h(f);(4)when F is generated by finite expanding endomorphisms with no coincidence point,the entropy formula of F is ***,the dynamics of the set-valued maps based on discontinuous maps on the interval are also considered.

关键词： Set-valued map orbit space hyperbolic endomorphism perturbation shadowing expansiveness topological stability entropy

A new liquid membrane diffusion model for characterizing the adsorption kinetics of europium by using a continuous measurement of adsorption platform

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Nuclear Science and Techniques 2024年第1期35卷 59-72页

作者： Hao-Qi yu Tao yu Jian-Hua Ye State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China CGN Cangnan Nuclear Power Co. Ltd.Cangnan 325800China Jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices East China University of TechnologyNanchang 330013China School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

To explore the kinetic adsorption under continuous and nonequilibrium states, an integration of continuous measurement and adsorption platform kinetics method was proposed, which was initially called the ICM-AP kinetics method, and a corresponding kinetic adsorption experimental method was developed. Adsorption experiments of europium(Eu) on Ca-bentonite,Na-bentonite, and the D231 cation exchange resin were performed using the ICM-AP kinetics method and continuous measurements. Because the kinetic experimental results observed in this study were different from those of traditional batch adsorption data, pseudo-first-order or pseudo-second-order kinetic models were unsuitable for fitting the experimental ***, a liquid membrane diffusion(LMD) model was developed based on the assumption of simultaneous adsorption/desorption to discuss the mechanism of kinetic adsorption. The kinetic adsorption mechanism was also studied by using *** results indicated that the proposed adsorption model can fit the experimental data more suitably, and the adsorption/desorption behaviors of Eu on bentonite and the D231 resin were simultaneously observed, suggesting that the adsorption kinetics of Eu(Ⅲ) was mainly dominated by hydrated Eu(Ⅲ) ions on the liquid membrane.

关键词： ICM-AP method LMD model Adsorption mechanism Eu(Ⅲ)

Exclusive enteral nutrition for treating pediatric Crohn’s disease

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World Journal of Pediatrics 2024年第9期20卷 869-871页

作者： yu yu Jie Chen Department of Gastroenterology Children’s HospitalNational Clinical Research Center for Child HealthZhejiang University School of MedicineHangzhou 310052China

Crohn's disease(CD),an enduring and relapsing condition afecting the gastrointestinal tract,manifests in a spectrum of symptoms and clinical manifestations that can profoundly afect quality of life[1].Recently,CD has emerged as a global burden of *** China,the prevalence and incidence of childhood infammatory bowel disease(IBD)have steadily increased,from 0.5 per 1 million in 2001 to 6.0 per 1 million in 2010[2].Pediatric patients often face a longer treatment duration than adults.

关键词： Crohn pediatric nutrition

Device design principles and bioelectronic applications for flexible organic electrochemical transistors

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International Journal of Extreme Manufacturing 2024年第1期6卷 126-153页

作者： Lin Gao Mengge Wu Xinge yu Junsheng yu State Key Laboratory of Electronic Thin Films and Integrated Devices School of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of China(UESTC)Chengdu 610054People’s Republic of China Department of Biomedical Engineering City University of Hong KongHong Kong Special Administrative Region of ChinaPeople’s Republic of China

Organic electrochemical transistors(OECTs) exhibit significant potential for applications in healthcare and human-machine interfaces, due to their tunable synthesis, facile deposition, and excellent biocompatibility. Expanding OECTs to the fexible devices will significantly facilitate stable contact with the skin and enable more possible bioelectronic applications. In this work,we summarize the device physics of fexible OECTs, aiming to offer a foundational understanding and guidelines for material selection and device architecture. Particular attention is paid to the advanced manufacturing approaches, including photolithography and printing techniques, which establish a robust foundation for the commercialization and large-scale fabrication. And abundantly demonstrated examples ranging from biosensors, artificial synapses/neurons, to bioinspired nervous systems are summarized to highlight the considerable prospects of smart healthcare. In the end, the challenges and opportunities are proposed for fexible OECTs. The purpose of this review is not only to elaborate on the basic design principles of fexible OECTs, but also to act as a roadmap for further exploration of wearable OECTs in advanced bio-applications.

关键词： flexible organic electrochemical transistors wearable bioelectronics manufacturing approaches device physics neuromorphic applications