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Non-homogeneous Tb Theorem for Bi-parameter g-function

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Acta Mathematica Sinica,English Series 2018年第9期34卷 1445-1459页

作者： Ming Ming CAO qing ying XUE School of Mathematical Sciences Beijing Normal University Laboratory of Mathematics and Complex Systems Ministry of Education

The main result of this paper is a bi-parameter Tb theorem for Littlewood-Paley g-function, where b is a tensor product of two pseudo-accretive function. Instead of the doubling measure, we work with a product measure μ = μn × μm, where the measures μn and μm are only assumed to be upper doubling. The main techniques of the proof include a bi-parameter b-adapted Haar function decomposition and an averaging identity over good double Whitney regions. Moreover, the non-homogeneous analysis and probabilistic methods are used again.

关键词： Bi-parameter square function probabilistic method b-adapted Haar functions

Convergence of the Cesaro Mean for Rational Orthonormal Bases

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Acta Mathematica Sinica,English Series 2009年第4期25卷 581-592页

作者： ying Xiong FU Luo qing LI Key Laboratory of Applied Mathematics Hubei ProvinceFaculty of Mathematics and Computer Science Hubei UniversityWuhan 430062 P. R. China

This paper deals with the convergence of the Cesaro mean for the rational orthonormal bases. Provided the set of zeroes of rational orthonormal bases is formed by a periodic repetition of the same finite sequence, the explicit expression of so-called block-Fejer kernel is available, and some properties of the block-Fejer kernel are discussed. Based on the convergence of the block-Cesaro mean, the convergence of Cesaro mean is also provided.

关键词： Cesaro mean trigonometric series rational orthonormal basis

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体相二硫化铼中点缺陷的形成与稳定性

原子与分子物理学报 2025年第5期42卷 143-150页

作者：何诗颖赵宇清邹代峰许英廖雨洁禹卓良湖南科技大学物理与电子科学学院湘潭411201 智能传感器与新型传感器材料湖南省重点实验室湘潭411201 湖南理工学院物理与电子科学学院岳阳414006

二硫化铼是过渡金属二硫族化合物的成员,由于层间的范德华作用、合适的带隙、高的光吸收系数和长的载流子迁移距离在光电子研究领域引起广泛的关注.其中光电材料及器件的优良特性由电子结构决定,而半导体的缺陷能级对电子结构具有重要... 详细信息

二硫化铼是过渡金属二硫族化合物的成员,由于层间的范德华作用、合适的带隙、高的光吸收系数和长的载流子迁移距离在光电子研究领域引起广泛的关注.其中光电材料及器件的优良特性由电子结构决定,而半导体的缺陷能级对电子结构具有重要的调控,且体相二硫化铼的缺陷研究尚且缺乏.本文基于密度泛函理论的第一性原理计算,对体相二硫化铼的铼空位、硫空位、钨掺杂(或替代)铼、钨掺杂硫、锝掺杂铼和锝掺杂硫的缺陷形成能和稳定性进行了研究.结果表明:钨掺杂硫和锝掺杂硫形成深施主能级缺陷,铼空位形成浅施主能级缺陷.在富铼和富硫条件下,钨掺杂铼的缺陷形成能低且能有效降低体系总能,提高体系稳定性.钨掺杂硫的缺陷虽然能降低体系的总能提高二硫化铼的稳定性,但较大的缺陷形成能表明钨掺杂硫缺陷难以形成.上述研究结果有助于理解缺陷能级对半导体深浅能级和稳定性的影响,同时也为未来实验上设计基于二硫化铼的高效的光电子器件提供理论依据.

关键词：体相二硫化铼形成能缺陷能级稳定性

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Integrated water resources management for emergency situations： A case study of Macao

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Journal of Environmental Sciences 2016年第12期28卷 72-78页

作者： Jian Yong Huang Inchio Lou ying xia Li Department of Civil and Environmental Engineering Faculty of Science and Technology University of Macao Macao SAR China State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China

Integrated urban water management （IUWM） is a useful tool that can be used to alleviate water resource shortages in developing regions like Macao, where 98% of the raw water comes from China's Mainland. In Macao, scarce water resources deteriorate rapidly in emergency situations, such as accidental chemical spills upstream of the supply reservoir or salty tides. During these times, only the water from the two freshwater reservoirs in Macao can be used. In this study, we developed urban water management optimization models that integrated the raw water supply from the two reservoirs with various proposed governmental policies （wastewater reuse, rainwater collection, and water saving）. We then determined how various water resource strategies would influence the urban water supply in Macao in emergency situations. Our results showed that, without imported raw water, the water supply from only the two Macao reservoirs would last for 7.95 days. However, when all the government policies were included in the model, the supply could be extended to 13.79 days. Out of the three non-conventional water resources, wastewater reuse is the most beneficial for increasing the Macao water supply, and rainwater collection also has great potential.

关键词： Emergency situations Integrated urban water management Macao Non-conventional water resources

Selectivity recovery of molybdenum(VI) from rhenium(VII) by amine-modified persimmon waste

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Rare Metals 2016年第6期35卷 502-508页

作者： Zhen-Ning Lou Ye-xia Li Fu-Qiang Ren qing Zhang Li Wan Zhi-Qiang Xing Shu-Liang Zang ying Xiong College of Chemistry Liaoning University

Amine functional group was grafted to obtain modified persimmon waste gel （NH2-CPT） with the focus of development of selective recovery of molybdenum from rhenium. The adsorption behavior of the NH2-CPT gel for various metal ions at varying hydrochloric acid concen-trations was studied. It is found that the NH2-CPT exhibits high affinity for Mo（VI） and no affinity for Re（VII）, Cu（II）, Fe（III）, Mn（VII）, and Zn（II） under the operating conditions. The maximum adsorption capacity for Mo（VI） is 172 mg·g^-1, and the adsorption behavior obeys the Langmuir model. Owing to Mo（VI） as poly-anions, the adsorption mechanism of molybdenum anions could be explained as the anion exchange reactions at weak acid concentration, while neutral molecules could be explained as the complexation reactions at strong acid concentration, respectively. In addition, its excellent adsorption characteristics for Mo（VI） are confirmed by separation of Mo（VI） from Mo to Re containing industrial effluent.

关键词： Persimmon Molybdenum Rhenium waste Adsorption Biomass Separation

Harmonic Transfer Function Based Single-input Single-output Impedance Modeling of LCC-HVDC Systems

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1327-1332页

作者： Yang Wang Fei xia ying Wang xianyong xiao College of Electrical Engineering Sichuan UniversityChengdu 610065China

This study presents a harmonic transfer function(HTF)based single-input single-output(SISO)impedance modeling *** method converts an HTF from phase domain to sequence domain and then transforms it into an SISO impedance while preserving the frequency coupling information of different sequences and different *** of this method to a line-commutated converter based high-voltage direct current(LCC-HVDC)system are *** results demonstrate the accuracy of the derived SISO impedance,and a truncation-order selection is *** case study shows that the proposed method facilitates simpler impedance measurements and associated stability analysis.

关键词： Line-commutated converter based high-voltage direct current(LCC-HVDC) harmonic transfer function(HTF) single-input single-output(SISO)impedance frequency coupling

Associations of Gestational Diabetes Mellitus and Excessive Gestational Weight Gain with Offspring Obesity Risk

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Current Medical Science 2022年第3期42卷 520-529页

作者： Qi LIU Wei xia Xin XIONG Ju-xiao LI ying LI Shun-qing XU Yuan-yuan LI Key Laboratory of Environment and Health Ministry of Education and Ministry of Environmental Protectionand State Key Laboratory of Environmental HealthSchool of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective Gestational diabetes mellitus(GDM)and gestational weight gain(GWG)are important risk factors that are known to affect offspring growth,but these outcomes are inconsistent and it remains unknown if both risk factors have a synergetic effect on early childhood *** present study aimed to conduct offspring body mass index-for-age Z-scores(BMIZ)trajectories and to evaluate the independent and interactive effect of the status of GDM and excessive GWG on the risks of overweight/obesity from birth to 24 months of *** A total of 7949 mother-child pairs were enrolled in this *** weight and length of children were measured at birth,6,12,and 24 months of age to calculate *** The status of GDM was positively associated with offspring BMIZ and risk of macrosomia at birth but was not associated with offspring BMIZ or the risks of overweight/obesity at 6,12,and 24 months of *** contrast,excessive GWG was positively linked to offspring BMIZ,the stable high BMIZ trajectory pattern,and risks of overweight/obesity in the first 24 months of *** two risk factors also had a significant synergistic effect on macrosomia at birth,but the interactive effect was only significant in boys during the follow-up years in the sex-stratified *** The maternal GWG was a more pronounced predictor than GDM with relation to BMIZ and risk of overweight/obesity in early *** interactive effect between these risk factors on offspring overweight/obesity may vary by sex.

关键词： gestational diabetes mellitus gestational weight gain offspring growth childhood overweight/obesity

Collective radiance of giant atoms in non-Markovian regime

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Science China(Physics,Mechanics & Astronomy) 2023年第2期66卷 79-86页

作者： qing-Yang Qiu ying Wu Xin-You Lü School of Physics Huazhong University of Science and TechnologyWuhan 430074China

We investigate the non-Markovian dynamics of two giant artificial atoms interacting with a continuum of bosonic modes in a onedimensional(1D) *** on the diagrammatic method,we present the exact analytical solutions,which predict the rich phenomena of collective *** the certain collective states,the decay rates are found to be far beyond that predicted in the the Dicke model and standard Markovian framework,which indicates the occurrence of *** superadiance-to-subradiance transition could be realized by adjusting the exchange symmetry of giant ***,there exist multiple bound states in continuum(BICs),with photons/phonons bouncing back and forth in the cavity-like geometries formed by the coupling *** trapped photons/phonons in the BICs can also be re-released conveniently by changing the energy level splitting of giant *** mechanism relies on the joint effects of the coherent time-delayed feedback and the interference between the coupling points of giant *** work fundamentally broadens the fields of giant atom collective radiance by introducing *** also paves the way for a clean analytical description of the nonlinear open quantum system with more complex retardation.

关键词： collective symmetry conveniently

Deformation-based freeform feature reconstruction in reverse engineering

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第9期9卷 1214-1228页

作者： qing WANG Jiang-xiong LI ying-lin KE State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

For reconstructing a freeform feature from point cloud, a deformation-based method is proposed in this paper. The freeform feature consists of a secondary surface and a blending surface. The secondary surface plays a role in substituting a local region of a given primary surface. The blending surface acts as a bridge to smoothly connect the unchanged region of the primary surface with the secondary surface. The secondary surface is generated by surface deformation subjected to line constraints, i.e., character lines and limiting lines, not designed by conventional methods. The lines are used to represent the underlying informa-tion of the freeform feature in point cloud, where the character lines depict the feature’s shape, and the limiting lines determine its location and orientation. The configuration of the character lines and the extraction of the limiting lines are discussed in detail. The blending surface is designed by the traditional modeling method, whose intrinsic parameters are recovered from point cloud through a series of steps, namely, point cloud slicing, circle fitting and regression analysis. The proposed method is used not only to effectively and efficiently reconstruct the freeform feature, but also to modify it by manipulating the line constraints. Typical examples are given to verify our method.

关键词： Freeform feature Surface deformation Fishbone structure Character line Limiting line Reverse engineering