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An overview of the environmental finance policies in China： retrofitting an integrated mechanism for environmental management

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Frontiers of Environmental Science & Engineering 2014年第3期8卷 316-328页

作者： wei LI Mengze hu State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China

Considering the significant roles of the policies in developing environmental finance, an overview is conducted on the environmental finance policies （EFPs） in China. This paper analyzed the definition, scope, evolution and main instruments of EFPs. The implementation progress of financial activities on each instrument are investigated respectively. Then the experiences learned from and failures discovered in the development of the EFPs are discussed well recommendations for further improvement of the EFPs and their implementation are provided. Our study found that the EFPs have been established in China after a four-phase evolution since the early 1980s. The policies have played a critical role in leading to a rapid development in environmental finance by involving more financial instruments to accomplish the objective-led environmental plans. Driven by the policies, the new green credit （GC）, green security （GS）, and green insurance （GI） instruments have been phased in as supplements to the conventional command and control approaches to improve the environmental governance of financial activities and pollution sources. However, the market mechanism of financial institution is limited due to their defensive and incapable performance on implementation some of EFP instruments. To further strengthen the effectiveness of EFPs in facilitating environmental man- agement, recommendations are made mainly on the aspects including developing more specific policy guidelines, enhancing information sharing and disclosure, providing sufficient economic incentives, establishing environmental liabilities with financial activities, and involving issues related to climate change, and biodiversity and ecosystem service.

关键词： environmental finance policy integrated mechanism phased evolution implementation progress,financial institution environmental management

CALCULATION OF PENALTIES IN ALGORITHM OF MIXEDINTEGER PROGRAMMING SOLVING WITH REVISED DUALSIMPLEX METHOD FOR BOUNDED VARIABLES

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Journal of Computational Mathematics 1999年第5期17卷 545-552页

作者： wei, YM hu, QH Chinese Acad Sci Inst Policy & Management Beijing 100080 Peoples R China Wuhan Inst Chem Technol Wuhan 430073 Peoples R China

The branch-and-bound method with the revised dual simplex for bounded variables is very effective in solving relatively large-size integer linear programming problems. This paper, based on the general forms of the penalties by Beale and Small and the stronger penalties by Tomlin, describes the modifications of these penalties used for the method of bounded variables. The same examples from Petersen are taken and the satisfactory results are shown in comparison with those obtained by Tomlin.

关键词： penalties stronger penalties the revised dual simplex method for bounded variables

Further study on hunt's hypothesis (H) for Lvy processes

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Science China Mathematics 2016年第11期59卷 2205-2226页

作者： hu ZeChun SUN wei College of Mathematics Sichuan University Chengdu 610065 China Department of Mathematics and Statistics Concordia University Montreal H3G 1M8 Canada

Getoor＇s conjecture that essentially all Levy processes satisfy hunt＇s hypothesis （H） is a long- standing open problem in potential theory. In the beginning of the paper, we summarize the main results obtained so far for the problem. Then, we present two new necessary and sufficient conditions for the validity of （H）. Furthermore, we give applications of these new criteria. First, we give explicit constructions of Levy processes satisfying （H） in a context where previously known results could not be applied. Second, we show that a large class of pure jump subordinators can be decomposed into the summation of two independent subordinators such that both of them satisfy （H）.

关键词： hunt's hypothesis (H) Getoor's conjecture Levy process subordinator

Metabolism Study on Tobacco-specific N-Nitrosamines in Rabbit by Solid-phase Extraction and Liquid Chromatography-electrospray Ionization-mass Spectrometry Method

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Chinese Chemical Letters 2005年第12期16卷 1633-1636页

作者： Jian Xun ZHANG Chen Chen LI Zheng CHEN Zhi hua RAO da wei WEN Ke An LI hu wei LIU College of Chemistry and Molecular Engineering Peking University Beijing 100871

Metabolism of four tobacco-specific N-nitrosamines （TSNAs）, N＇-nitrosonornicotine （NNN）, N＇-nitrosoanatabine （NAT）, N＇-nitrosoanabasine （NAB） and 4-（methyl nitrosamino）-1- （3-pyridyl）-1-butanone （NNK） was studied by solid-phase extraction （SPE） and liquid chromato- graphy-electrospray ionization-mass spectrometry （LC-ESI-MS）. SPE and LC-ESI-MS method was evaluated to be rapid, simple, sensitive and selective for analysis of TSNAs in rabbit serum. The doses of TSNAs administrated were 4.666 μg/kg and 11.665 μg/kg according to different levels in cigarettes. Metabolic curves of four TSNAs and 4-（methyl nitrosamino）-1-（3-pyridyl）- 1-butanone （NNAL）, the metabolite of NNK, were obtained.

关键词： Tobacco-specific N-nitrosamines metabolism liquid chromatography-electrosprayinterface-mass spectrometry

hunt’s Hypothesis(H) for Markov Processes: Survey and Beyond

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Acta Mathematica Sinica,English Series 2021年第3期37卷 491-508页

作者： Ze Chun hu wei SUN College of Mathematics Sichuan UniversityChengdu 610065P.R.China Department of Mathematics and Statistics Concordia UniversityMontrealH3G 1M8Canada

The goal of this paper is threefold. First, we survey the existing results on hunt’s hypothesis(H) for Markov processes and Getoor’s conjecture for Lévy processes. Second, we investigate(H)for multidimensional Lév... 详细信息

关键词： hunt’s hypothesis(H) Getoor’s conjecture Markov process Lévy process

Nonlinear Evolutions of Stimulated Raman and Brillouin Scattering Processes in Partially Stripped-Ion Plasmas

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Chinese Physics Letters 2001年第9期18卷 1230-1233页

作者： hu Ye-Min hu Xi-wei Departmentof Electrical Engineering Huazhong University of Science and TechnologyWuhan 430074 Department of Modern Physics University of Science and Technology of ChinaHefei 230026

Numerical analyses for the nonlinear evolutions of stimulated Raman scattering (SRS) and stimulated Brillouin scattering (SBS) processes are given. Various effects of the second- and third-order nonlinear susceptibilities on the SRS and SBS processes are studied. The nonlinear evolutions of SRS and SBS processes are atfected more efficiently than their linear growth rates by the nonlinear susceptibility.

关键词： Brillouin nonlinear Nonlinear

Effect of zirconium on microstructures and mechanical properties of squeeze cast Al-5.0Cu-0.4Mn-0.1Ti-0.1RE alloy

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Journal of Central South University 2017年第10期24卷 2231-2237页

作者： MENG Fan-sheng ZHANG wei-wen hu Yuan ZHANG da-tong YANG Chao National Engineering Research Center of Near-net-shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China

Al–5.0Cu–0.4Mn alloys with different Zr additions have been prepared by direct squeeze *** effects of Zr on microstructures and mechanical properties of the as-cast and T6 heat-treated alloys were investigated by tensile test,optical microscope(OM),scanning electron microscope(SEM)and transmission electron microscope(TEM).The results show that the optimal tensile property of the as-cast alloy occurs at the Zr content of 0.15%(mass fraction)due to the"Zr poisoning"action and the appearance of bulky primary Al_3Zr,which decreases the grain refinement strengthening effect of the as-cast *** peak values of ultimate tensile strength and yield strength of the T6 alloy occur at the Zr content of 0.25%,and that of the elongation occurs at Zr content of 0.05%.This is mainly attributed to the strengthening effect of dispersed precipitation of Al_3Zr and??*** optimal mechanical properties of T6 heat-treated alloy are the tensile strength of 429 MPa,the yield strength of 327 MPa and the elongation of 18%,respectively when the squeeze pressure is 100 MPa and Zr content is 0.25%.

关键词： Zr squeeze pressure mechanical property microstructure

Dynamically self-adjustable liquid-liquid and self-adaptive softcontact solid-solid triboelectric nanogenerator for wave energy harvesting

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Nano Research 2025年第1期18卷 404-414页

作者： Yong Long Bingqi Zhao Jianan Niu Yuxiu Liu wei Sha Jiangwen Wang Zhong Lin Wang weiguo hu Guangzhou Institute of Blue Energy Knowledge CityHuangpu DistrictGuangzhou 510555China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049China

Water wave energy exhibits great potential toalleviate the global energy crisis. However, harvesting andutilizing wave energy are challenging due to its irregularity,randomness, and low frequency. Triboelectric nanogenerators(TENGs) have gained significant attention for harvesting waveenergy with high efficiency. This study presents a novelellipsoidal, pendulum-like TENG integrating both liquid-liquid(L-L) and solid-solid (S-S) triboelectricity (LS-TENG). Thisinnovative design enables continuous wave energy harvestingand self-powered marine environment monitoring under variousconditions, including temperature, humidity, and light intensity. The binary immiscible liquids within the LS-TENG’s innersoft balloon create dynamic, and self-adjustable L-L contact interfaces, significantly increasing the L-L contact area andenhancing L-L contact electrification (CE). The unique self-adaptive, soft S-S contact increases the S-S contact areacompared to traditional hard point contact, better adapting to the irregular movements of waves and promoting efficient S-SCE. The LS-TENG achieves highly efficient wave energy harvesting by coupling L-L and S-S CE. Furthermore, the uniquesoft contact design protects the S-S interfaces from mechanical wear and damage during long-term work. The LS-TENG’snovel structure provides an innovative and effective way for water wave energy harvesting.

关键词： self-adaptive soft-contact solid-solid liquid-liquid self-adjustable triboelectric nanogenerator

Low-frequency and broadband vibration energy harvester driven by mechanical impact based on layer-separated piezoelectric beam

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Applied Mathematics and Mechanics(English Edition) 2019年第12期40卷 1777-1790页

作者： Dongxing CAO wei XIA Wenhua hu College of Mechanical Engineering Beijing University of TechnologyBeijing 100124China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures Beijing 100124China School of Mechanical Engineering Tianjin University of TechnologyTianjin 300384China

Vibration energy harvesting is to transform the ambient mechanical energy to electricity. How to reduce the resonance frequency and improve the conversion efficiency is very important. In this paper, a layer-separated piezoelectric cantilever beam is proposed for the vibration energy harvester(VEH) for low-frequency and wide-bandwidth operation, which can transform the mechanical impact energy to electric energy. First,the electromechanical coupling equation is obtained by the Euler-Bernoulli beam *** on the average method, the approximate analytical solution is derived and the voltage response is obtained. Furthermore, the physical prototype is fabricated, and the vibration experiment is conducted to validate the theoretical principle. The experimental results show that the maximum power of 0.445 μW of the layer-separated VEH is about3.11 times higher than that of the non-impact harvester when the excitation acceleration is 0.2 g. The operating frequency bandwidth can be widened by increasing the stiffness of the fundamental layer and decreasing the gap distance of the system. But the increasing of operating frequency bandwidth comes at the cost of reducing peak voltage. The theoretical simulation and the experimental results demonstrate good agreement which indicates that the proposed impact-driving VEH device has advantages for low-frequency and wide-bandwidth. The high performance provides great prospect to scavenge the vibration energy in environment.

关键词： vibration energy harvester(VEH) layer-separated piezoelectric b eam low frequency broad-bandwidth