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Metal-organic framework-derived porous shuttle-like vanadium oxides for sodium-ion battery application

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Nano Research 2018年第1期11卷 449-463页

作者： yangsheng cai Guozhao Fang Jiang Zhou Sainan Liu Zhigao Luo Anqiang Pan Guozhong Cao I Shuquan Liang School of Materials Science and Engineering Central South University Changsha 410083 China Key Laboratory of Nonferrous Metal Materials Science and Engineering Ministry of Education Central South University Changsha 410083 China Department of Materials and Engineering University of Washington Seattle WA 98195-2120 USA

Vanadium oxides with a layered structure are promising candidates for both lithium-ion batteries and sodium-ion batteries （SIBs）. The self-template approach, which involves a transformation from metal-organic frameworks （MOFs） into porous metal oxides, is a novel and effective way to achieve desirable electrochemical performance. In this stud~ porous shuttle-like vanadium oxides （i.e., V205, V203/C） were successfully prepared by using MIL-88B （V） as precursors with a specific calcination process. As a proof-of-concept application, the as- prepared porous shuttle-like VaOdC was used as an anode material for SIBs. The porous shuttle-like V203/C, which had an inherent layered structure with metallic behavior, exhibited excellent electrochemical properties. Remarkable rate capacities of 417, 247, 202, 176, 164, and 149 mAh.g-1 were achieved at current densities of 50, 100, 200, 500, 1,000, and 2,000 mA.g-1, respectively. Under cycling at 2 A.g-1, the specific discharge capacity reached 181 mAh.g-1, with a low capacity fading rate of 0.032% per cycle after 1,000 cycles. Density functional theory calculation results indicated that Na ions preferred to occupy the interlamination rather than the inside of each layer in the V203. Interestingly, the special layered structure with a skeleton of dumbbell-like V-V bonds and metallic behavior was maintained after the insertion of Na ions, which was beneficial for the cycle performance. We consider that the MOF precursor of MIL-88B （V） can be used to synthesize other porous V-based materials for various applications.

关键词： vanadium oxides metal-organic frameworks porous structure density functional theory(DFT) calculation sodium-ion batteries

声压法与声强法的隔声测量不确定度的对比研究

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振动与冲击 2018年第8期37卷 42-46,53页

作者：蔡阳生赵越喆福建工程学院建筑与城乡规划学院福州350118 华南理工大学亚热带建筑科学国家重点实验室广州510640

利用计算隔声单值量及其测量不确定度的方法,根据ISO 12999-1以及GB/T 31004.1—2014给出的标准偏差,分别计算声压法和声强法在普通频率范围(100~5 000 Hz)以及低频扩展范围(50~5 000 Hz)的测量不确定度。结果表明声强法在普通频率范围... 详细信息

利用计算隔声单值量及其测量不确定度的方法,根据ISO 12999-1以及GB/T 31004.1—2014给出的标准偏差,分别计算声压法和声强法在普通频率范围(100~5 000 Hz)以及低频扩展范围(50~5 000 Hz)的测量不确定度。结果表明声强法在普通频率范围的不确定度小于声压法,在低频扩展范围时会更显著小于声压法,这体现了声强法有更好的低频段测量鲁棒性,与前人的实验对比研究结果一致。最后对比了两个隔声构件的不确定度,结果显示构件的低频隔声性能较差会产生较大的不确定度。

关键词：空气声隔声测量不确定度声压声强

城市道路交通噪声频谱及其对隔声评价中频谱修正量的影响

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振动与冲击 2024年第19期43卷 287-297页

作者：蔡阳生陈智慧 AKRAM A N A 袁旻忞福建理工大学建筑与城乡规划学院福州350118 福建理工大学土木工程学院福州350118 国家环境保护道路交通噪声控制工程技术中心北京100088 交通运输部公路科学研究院北京100088

现行隔声评价标准中交通噪声频谱修正量参考的是20世纪80年代北欧测量得到的交通噪声数据。为了研究C_(tr)修正量是否适用于评价建筑外窗对新时代城市道路交通噪声的隔声性能,对多种城市交通道路进行噪声监测,根据测量结果提出一组新的... 详细信息

现行隔声评价标准中交通噪声频谱修正量参考的是20世纪80年代北欧测量得到的交通噪声数据。为了研究C_(tr)修正量是否适用于评价建筑外窗对新时代城市道路交通噪声的隔声性能,对多种城市交通道路进行噪声监测,根据测量结果提出一组新的交通噪声频谱修正曲线C_(A),计算11种常见外窗构造在不同频率范围内的计权隔声量,并对比分析不同频谱修正量声压级频谱的差异性。结果表明:不同城市道路交通噪声频谱都具有低频声压级高、中频平稳、高频下降的相似特点;当今的城市道路交通噪声低频能量远低于C_(tr)所参考的频谱,其能量频谱分布更接近于C_(100~3150);对比分析11组外窗的交通噪声频谱修正量C_(A)与现行标准的频谱修正量的差异,C_(A)均落于C和C_(tr)参考频谱之间的范围内;C_(A)与C、C_(tr)参考频谱的相关系数R2的值均>0.9且高于C与C_(tr)的相关性,因此C_(A)对城市道路交通噪声频谱修正具有更好的适用性与代表性,研究结果可为临街住宅的隔声降噪工程提供数据参考。

关键词：城市道路交通噪声隔声频谱修正量外窗

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福州地区宫庙类传统戏场音质研究

北京师范大学学报（自然科学版） 2019年第3期55卷 329-335页

作者：缪远黄巍蔡阳生福建工程学院建筑与城乡规划学院福建福州350118 西安建筑科技大学建筑学院陕西西安710055 福建工程学院建筑声光工程研究中心福建福州350118

传统戏场是中国传统建筑的重要类型,其音质不仅和传统戏曲的特性相互影响,也是传统建筑保护和研究的重要内容.本文以福州地区2个具有代表性的典型性宫庙类戏场建筑为实例,结合历史建筑测绘与现代声学测量2种方法,对其声学参数进行实验研... 详细信息

传统戏场是中国传统建筑的重要类型,其音质不仅和传统戏曲的特性相互影响,也是传统建筑保护和研究的重要内容.本文以福州地区2个具有代表性的典型性宫庙类戏场建筑为实例,结合历史建筑测绘与现代声学测量2种方法,对其声学参数进行实验研究.由实验结果可以看出,传统戏场声环境的混响时间、早期衰变时间等声学参数的频率特性较为平直,且有较好的清晰度.这些结果可为传统戏场的保护以及新型传统戏场声学设计提供依据.

关键词：传统戏场戏台声学设计早期衰变时间清晰度

隔声室条件下建筑隔声性能测量方法的高频偏差研究

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建筑科学 2017年第2期33卷 134-137,147页

作者：蔡阳生李倩李积权福建工程学院建筑与城乡规划学院福州350118 广州大学机械与电气工程学院广州510006 燕山大学建筑工程与力学学院河北秦皇岛066004

声强法测量隔声量可抑制侧向传声且有更好的再现性,有望为绿色建筑声环境评价提供更方便、更可靠的测量手段。本文主要研究声强法和声压法测量隔声量时高频范围的偏差,这对推广声强法在绿色建筑声环境评价的应用有重要意义。本文首先介... 详细信息

声强法测量隔声量可抑制侧向传声且有更好的再现性,有望为绿色建筑声环境评价提供更方便、更可靠的测量手段。本文主要研究声强法和声压法测量隔声量时高频范围的偏差,这对推广声强法在绿色建筑声环境评价的应用有重要意义。本文首先介绍了建筑隔声测量的原理,然后从三方面讨论了2种方法产生再现性偏差的原因,包括基于声压的声功率测量再现性、声强测量的有限差分误差以及基于声强的声功率测量再现性。由于声功率的2种测量方法的再现性偏差都是随着频率上升而减小,而且声强测量在采用有限差分误差修正后,可以消除其高频偏差,因此本文指出2种方法在高频范围的偏差应小于ISO 15186标准的要求范围,这有助于明确2种测量方法在高频范围并不存在系统偏差。

关键词：隔声量声强高频偏差

Value Iteration-Based Distributed Adaptive Dynamic Programming for Multi-Player Differential Game With Incomplete Information

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 436-447页

作者： Yun Zhang Yuqi Wang Yunze cai the Department of Automation Shanghai Jiao Tong University the Key Laboratory of System Control and Information Processing Ministry of Education of China the National Key Laboratory of Air-based Information Perception and Fusion

In this paper, a distributed adaptive dynamic programming(ADP) framework based on value iteration is proposed for multi-player differential games. In the game setting,players have no access to the information of others' system parameters or control laws. Each player adopts an on-policy value iteration algorithm as the basic learning framework. To deal with the incomplete information structure, players collect a period of system trajectory data to compensate for the lack of information. The policy updating step is implemented by a nonlinear optimization problem aiming to search for the proximal admissible policy. Theoretical analysis shows that by adopting proximal policy searching rules, the approximated policies can converge to a neighborhood of equilibrium policies. The efficacy of our method is illustrated by three examples, which also demonstrate that the proposed method can accelerate the learning process compared with the centralized learning framework.

关键词： Distributed adaptive dynamic programming incomplete information multi-player differential game (MPDG) value iteration

Profiles,exposure assessment and expanded screening of PAHs and their derivatives in one petroleum refinery facility of China

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Journal of Environmental Sciences 2025年第1期147卷 550-560页

作者： Ning Wang Fengjiao Jiang Lin Xu Yaqi cai School of Municipal and Environmental Engineering Shandong Jianzhu UniversityJinan 250101China Resource and Environmental Innovation Institute Shandong Jianzhu UniversityJinan 250101China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Environment Hangzhou Institute for Advanced StudyUCASHangzhou 330106China Hubei Key Laboratory of Environmental and Health Effects of Persistence Toxic Substances Institute of Environment and HealthJianghan UniversityWuhan 430056China

This study investigated environmental distribution and human exposure of polycyclic aromatic hydrocarbons(PAHs)and their derivatives in one Chinese petroleum refinery *** was found that,following with high concentrations of 16 EPA PAHs(∑Parent-PAHs)in smelting subarea of studied petroleum refinery facility,total derivatives of PAHs[named as XPAHs,including nitro PAHs(NPAHs),chlorinated PAHs(Cl-PAHs),and brominated PAHs(Br-PAHs)]in gas(mean=1.57×10^(4)ng/m^(3)),total suspended particulate(TSP)(mean=4.33×10^(3) ng/m^(3))and soil(mean=4.37×10^(3) ng/g)in this subarea had 1.76-6.19 times higher levels than those from other subareas of this facility,surrounding residential areas and reference areas,indicating that petroleum refining processes would lead apparent derivation of ***,compared with those in residential and reference areas,gas samples in the petrochemical areas had higher∑NPAH/∑PAHs(mean=2.18),but lower∑Cl-PAH/∑PAHs(mean=1.43×10^(-1))and∑Br-PAH/∑PAHs ratios(mean=7.49×10^(-2)),indicating the richer nitrification of PAHs than chlorination during petrochemical *** occupational exposure to PAHs and XPAHs in this petroleum refinery facility were 24-343 times higher than non-occupational exposure,and the ILCR(1.04×10^(-4))for petrochemical workers was considered to be potential high ***,one expanded high-resolution screening through GC Orbitrap/MS was performed for soils from petrochemical area,and another 35 PAHs were found,including alkyl-PAHs,phenyl-PAHs and other species,indicat-ing that profiles and risks of PAHs analogs in petrochemical areas deserve further expanded investigation.

关键词： Polycyclic aromatic hydrocarbons(PAHs) Derivatives Petroleum refinery Human exposure Non-targeted screening

Global adaptive output feedback control of nonlinear time-delay systems with measurement uncertainty

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Control Theory and Technology 2025年第1期23卷 145-152页

作者： Weiguo cai Xianglei Jia Xinxu Ju School of Automation Hangzhou Dianzi UniversityHangzhou310018ZhejiangChina

In this paper,a pair of dynamic high-gain observer and output feedback controller is proposed for nonlinear systems with multiple unknown time *** constructing Lyapunov-Krasovskii functionals,it shows that global state asymptotic regulation can be ensured by introducing a single dynamic gain;furthermore,global asymptotic stabilization can be achieved by choosing a sufficiently large static scaling gain when the upper bounds of all system parameters are ***,the output coefficient is allowed to be non-differentiable with unknown upper *** paper proposes a generalized Lyapunov matrix inequality based dynamic-gain scaling method,which significantly simplifies the design computational complexity by comparing with the classic backstepping method.

关键词： Output feedback Measurement uncertainty Nonlinear adaptive control Time delays

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng Li Meifeng cai Shengjun Miao Yuan Li Yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification