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Oscillatory hyper Hilbert transforms along curves

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Applied Mathematics(A Journal of Chinese Universities) 2009年第3期24卷 336-342页

作者： CHEN jie-cheng FAN Da-shan WANG Meng Dept. of Math. Zhejiang University Hangzhou 310027 China Dept. of Mathematical Sciences University of Wisconsin-Milwaukee Milwaukee Wisconsin 53201

The hyper Hilbert transform Tnf（x） =∫-1^1 f（x - Γ（t））e^-i｜t｜-β｜t｜^-1-αdt along an appropriate curve Γ（t） on R^n is investigated,where β 〉 α 〉 *** L^p boundedness theorem of T4 is obtained,which is... 详细信息

关键词： hyper Hilbert transform curve

Ammonia volatilization from a Chinese cabbage field under different nitrogen treatments in the Taihu Lake Basin, China

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Journal of Environmental Sciences 2015年第12期27卷 14-23页

作者： Linan shan Yunfeng He jie Chen Qian Huang Hongcai Wang College of Environmental and Resource Science Zhejiang University Ministry of Agriculture Key Laboratory of Non-point Source Pollution Control

Ammonia（NH3） volatilization is a major pathway of nitrogen（N） loss from soil-crop *** vegetable cultivation is one of the most important agricultural land uses worldwide,a deeper understanding of NH3 volatilization is necessary in vegetable production *** therefore conducted a 3-year（2010-2012） field experiment to characterize NH3 volatilization and evaluate the effect of different N fertilizer treatments on this process during the growth period of Chinese *** volatilization rate,rainfall,soil water content,p H,and soil NH4~＋were measured during the growth *** results showed that NH3 volatilization was significantly and positively correlated to topsoil p H and NH4＋*** factors and fertilization method also significantly affected NH3 ***,organic fertilizer（OF） increased NH3 volatilization by 11.77%-18.46%,compared to conventional fertilizer（CF,urea）,while organic-inorganic compound fertilizer（OIF） reduced NH3 volatilization by 8.82%-12.67% compared to ***,slow-release fertilizers had significantly positive effects on controlling NH3 volatilization,with a 60.73%-68.80% reduction for sulfur-coated urea（SCU）,a 71.85%-78.97% reduction for biological Carbon Power~？ urea（BCU）,and a 77.66%-83.12% reduction for bulk-blend controlled-release fertilizer（BBCRF）relative to *** study provides much needed baseline information,which will help in fertilizer choice and management practices to reduce NH3 volatilization and encourage the development of new strategies for vegetable planting.

关键词： Ammonia volatilization Nitrogen fertilizer Slow-release fertilizer Vegetable soil

Mesoporous TiO2 Nanofiber as Highly Efficient Sulfur Host for Advanced Lithium–Sulfur Batteries

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Chinese Journal of Mechanical Engineering 2019年第4期32卷 207-212页

作者： Xinyu shan Zuoxing Guo Xu Zhang jie Yang Lianfeng Duan Key Laboratory of Automobile Materials School of Materials Science and Engineering Jilin University Changchun 130025China Advanced Institute of Materials Science & Department of Materials Science and Engineering Changchun University of Technology Changchun 130012 China

Currently, lithium–sulfur batteries su er from several critical limitations that hinder their practical application, such as the large volumetric expansion of electrode, poor conductivity and lower sulfur utilization. In this work, TiO2 nanofibers with mesoporous structure have been synthesized by electrospinning and heat treating. As the host material of cathode for Li–S battery, the as prepared samples with novelty structure could enhance the conductivity of cathode composite, promote the utilization of sulfur, and relieve volume expansion for improving the electrochemical property. The initial discharge capacity of TiO2/S composite cathode is 703 mAh/g and the capacity remained at 652 mAh/g after 200 cycles at 0.1 C, whose the capacity retention remains is at 92.7%, demonstrating great prospect for application in high-performance Li–S batteries.

关键词： TiO2 nanofibers Mesoporous structure Lithium–sulfur batteries Cathode Electrochemical property

Toric Difference Variety

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Journal of Systems Science & Complexity 2017年第1期30卷 173-195页

作者： GAO Xiao-shan HUANG Zhang WANG jie YUAN Chun-Ming Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems ScienceChinese Academy of Sciences Department of Applied Mathematics Chengdu University of Technology

In this paper, the concept of toric difference varieties is defined and four equivalent descriptions for toric difference varieties are presented in terms of difference rational parametrization,difference coordinate rings, toric difference ideals, and group actions by difference tori. Connections between toric difference varieties and affine N[x]-semimodules are established by proving the one-to-one correspondence between irreducible invariant difference subvarieties and faces of N[x]-semimodules and the orbit-face correspondence. Finally, an algorithm is given to decide whether a binomial difference ideal represented by a Z[x]-lattice defines a toric difference variety.

关键词： Afflne N[x]-semimodule difference torus T-orbit toirc difference ideal toric differencevariety Z[x]-lattice.

Organic matter and pH affect the analysis efficiency of (31)P-NMR

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Journal of Environmental Sciences 2016年第5期28卷 244-249页

作者： Wenqiang Zhang Xin Jin Nan Rong jie Li Baoqing shan State Key Laboratory on Environmental Aquatic Chemistry Research Center for Eco-Environmental Science Chinese Academy of ScienceBeijing 100085 China University of Chinese Academy of Science Beijing 100049 China

Solution ^（31）P nuclear magnetic resonance spectroscopy（ ^（31）P-NMR） is a useful method to analyze organic phosphorus（Po）, but a general procedure for the analysis method is *** authors used solution ^（31）P-NMR, which was found to be an effective method for analysis of Po in Haihe River sediment, to analyze the Po in the surface sediment in Eastern China at the regional scale, and found that the Na OH-ethylenediaminetetraacetic acid（EDTA）extraction rate was affected by environmental factors. At the regional scale, the extraction rate showed a positive relationship with loss on ignition, when the extraction rate was lower than 60%. The extraction rate had no relationship with the loss on ignition when the extraction rate was higher than 60%. The extraction rate showed a negative relationship with p H, which means that the extraction rate was higher in acidic sediment and lower in alkaline sediment. The ratio of TC/TN（the ratio of total carbon to total nitrogen） was considered to represent the origin of organic matter in the sediment. The extraction rate was high when the TC/TN ratio was lower than 20, meanwhile the extraction rate decreased as the TC/TN ratio increased. The results show that the origin of organic matter in sediment significantly affects the Na OH-EDTA extraction rate. This study will give theoretical support for building an effective and general solution ^（31）P-NMR analysis method.

关键词： 31P-NMR pH Organic matter Extraction rate Sediment

Deep-Red to Near-Infrared Carbon Dots in Biosensing and Bio-medical Applications

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Chinese Journal of Chemistry 2023年第18期41卷 2354-2370页

作者： shan Huang Li Yan Xiaojun Chen Jun-jie Zhu Schoolof Chemistry and Molecular Engineering Nanjing TechUniversityNanjingJiangsu 211816China Schoolof Chemistry and chemical Engineering Nanjing UniversityNanjingJiangsu 210023China

Comprehensive Summary,With the rapid development in the field of biomedical diagnosis and treatment,carbon dots(CDs)with favorable photostability,biocompatibility and high quantum yields for deep-red to near-infrared emission have attracted the attention of a majority of *** enlarging the sp2 domain in the core of CDs,doping them with heteroatoms like nitrogen and sulfur,applying hydrothermal,electrochemical,or microwave-assisted techniques,CDs can be made with the aforementioned photoemission *** view of these excellent properties,CDs are flourishing in biosensing and biomedical applications,so that a thorough description and discussion of this topic is beneficial to capture the up-to-date progress of CDs in this field,providing suggestions and considerations for readers.

关键词： Carbon dots Biosensing Biomedical Biotechnology Cancer therapy Antibacterial

Approximation of the Fractional Schrodinger Propagator on Compact Manifolds

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Acta Mathematica Sinica,English Series 2021年第10期37卷 1485-1496页

作者： jie Cheng CHEN Da shan FAN Fa You ZHAO Department of Mathematics Zhejiang Normal UniversityJinhua 321000P.R.China Department of Mathematical Sciences University of Wisconsin–MilwaukeeMilwaukeeWI 53201USA Department of Mathematics Shanghai UniversityShanghai 200444P.R.China

Let L be a second order positive,elliptic differential operator that is self-adjoint with respect to some C^(∞)density dx on a compact connected manifold *** proved that if 00.

关键词： Schrodinger propagator almost everywhere convergence compact manifolds

Distribution of α-, β-, and γ-Phases in a Multi-flow Injection-molded Hierarchical Structure

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Chinese Journal of Polymer Science 2018年第6期36卷 765-775页

作者： Da-shan Mi Feng-Yi Hou Man Zhou jie Zhang College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University

In the current work, a custom-made vibration injection molding device that can provide oscillatory pressure was utilized to create an injection-molded hierarchical structure. Growth competition among α, β, and γ phases in the injection-molded structure can be studied because of the presence of this hierarchical structure, wherein shish-kebab and spherulite layers were arranged alternately along the thickness direction. The γ crystals only existed in layers subjected to high pressure and shear stress, whereas β crystals formed between the shear layers. The change in trend of the γ fraction was similar to that of parent-to-daughter ratio. In addition, this hierarchical and alternating crystal structure can sharply increase the mechanical properties.

关键词： Shish-kebab Growth competition α Phase γ Phase β Phase

Numerical simulations of solidification and hot tearing for continuous casting of duplex stainless steel

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Journal of Iron and Steel Research International 2020年第6期27卷 643-655页

作者： shan-shan Liu Liang Bai Bo Wang Yu Yao Jun-kai Huang Zheng Chen jie-yu Zhang State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200072China School of Materials Science and Engineering Shanghai UniversityShanghai 200072China Inner Mongolia Key Laboratory of Graphite and Graphene for Energy Storage and Coating Huhhot 010051Inner MongoliaChina Inner Mongolia University of Technology Huhhot 010051Inner MongoliaChina

Hot tearing is one of the major defects in continuous casting of steels, which severely limits the productivity of steelmaking processes. To further understand the defect, the problem of hot tearing in duplex stainless steel produced by a vertical continuous caster was investigated. A three-dimensional heat transfer and elastic-plastic model was developed based on the realistic roller layout in continuous slab casting, using ProCAST software. According to the hot tearing indicator criterion, the influence of operating parameters on the hot tearing susceptibility was evaluated. The results show that the surface temperature distribution is not sensitive to the superheat. The center of wide surface shell at the mold exit is the thinnest, and the thickness is about 10.52 mm at the superheat temperature of 40 -C. The hot tearing mainly concentrates on the slab solidification front and near the narrow face. However, corner cracks are prone to appear near the corner. With the increase in casting speed and the decrease in the cooling intensity in the secondary cooling zone, the solidification end point is rushed, which leads to the position of hot tearing lowering accordingly.

关键词： Hot tearing Duplex stainless steel Numerical simulation Solidification Continuous casting