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单一及多组分混合物绿松石仿制品的光谱学特征研究

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光谱学与光谱分析 2025年第1期45卷 183-190页

作者：杨池玉汪田田张维肖汤维茜同济大学浙江学院浙江嘉兴314051

对市场新出现的一类仿制品进行了拉曼光谱、红外光谱、化学成分、紫外-可见-近红外吸收光谱分析,对其主要谱学特征进行了归纳总结。结果表明这类仿制品主要由重晶石、三水铝石、方解石粉末单一组分或多组分混合压制再经环氧树脂类或丙... 详细信息

对市场新出现的一类仿制品进行了拉曼光谱、红外光谱、化学成分、紫外-可见-近红外吸收光谱分析,对其主要谱学特征进行了归纳总结。结果表明这类仿制品主要由重晶石、三水铝石、方解石粉末单一组分或多组分混合压制再经环氧树脂类或丙烯酸酯类有机物胶结,并经人工染剂染色而成。红外光谱显示:单一矿物组分仿制品和绿松石差异明显,重晶石仿制品显示[SO_(4)]^(2-)的1078 cm^(-1)吸收峰等,方解石仿制品显示[CO_(3)]^(2-)的1476±cm^(-1)吸收峰等;多组分仿制品可见综合了多种矿物特征的吸收光谱,谱学特征复杂。根据缺失水峰,或仅显示三水铝石结构水OH-导致的3623、3528、3472和3388 cm^(-1)吸收峰,指纹区显示[SO_(4)]^(2-)、[CO_(3)]^(2-)相关吸收峰,可初步区分于绿松石。显微拉曼光谱测试结果表明多组分仿制品的不同测试位置矿物组成不同,可分别测试到三水铝石(3360、3432、3522、3614 cm^(-1))、重晶石(989 cm^(-1))、方解石(1088 cm^(-1))的特征峰,结合显微拉曼光谱及化学分析结果可进一步确认仿制品的具体矿物组成。紫外-可见-近红外吸收光谱表明样品均经人工染剂染色,显示633±、713±nm吸收宽峰或610±、675±nm吸收宽峰。

关键词：三水铝石重晶石方解石振动光谱微区分析

A modern survey method for determining live loads based on multi-source and open-access data on the Internet

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Frontiers of Structural and Civil Engineering 2024年第8期18卷 1135-1147页

作者： chi XU Jun CHEN Jie LI School of Civil Engineering Tongji UniversityShanghai 200092China The State Key Laboratory on Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

Sufficient survey data are required to describe the stochastic behaviors of live ***,due to manual and on-site operation required by traditional survey methods,traditional surveys face challenges like occupant resistance,high costs,and long implementation *** study proposes a new survey method to access live load data online and *** samples are acquired from multi-source,open-access and dynamically updated data on the *** change intervals,geometrical dimensions and object quantities are obtained from transaction information,building attributes and virtual reality models on real estate websites,*** object weights are collected from commodity information on e-commerce *** integration of the aforementioned data allows for the extraction of necessary statistics to describe a live load *** proposed method is applied to a live load survey in china,covering 20040 m^(2),with around 90000 samples acquired for object weights and load *** survey results reveal that about 70%−80%of the amplitude statistics are attributable to 1/6 of the total object types.

关键词： live load online survey method data acquisition data integration

Numerical test of scale relations for modelling coastal sandbar migration and inspiration to physical model design

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Journal of Hydrodynamics 2022年第4期34卷 700-711页

作者： Yuan Li chi Zhang Shan-hang chi Yun-han Yang Jian Shi Ti-ti Sui State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210024China College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210024China State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200241China

Physical model experiments on sandbar migration are widely conducted in the wave flume to reveal its hydro-sediment dynamic *** an appropriate scale relation is an important part of designing a laboratory ***,evaluating the scale effect is complicated since it is impractical to design wave flume experiments based on strict geometry scales derived from the prototype beach or other laboratory ***,a process-based numerical model is used to test the Dean and Shields similitudes by comparing sandbar migration and sediment transport in different undistorted model scales using natural *** numerical model provides excellent predictions for both offshore sandbar migration on a real-world beach and onshore sandbar migration in the wave *** with previous studies,sandbar offshore migration and suspended sediment transport are similar when the Dean similitude is *** onshore migration and bedload transport can be well reproduced only if the Shields similitude is *** previous laboratory experiments of sandbar migration generally used the Dean similitude,it is found that the Shields similitude is effective and indispensable for modelling sandbar onshore migration,which will be underestimated if the Dean similitude is only *** scale relation cannot be used simultaneously for modelling both onshore and offshore sandbar migration in physical models.

关键词： Coastal sandbar migration sediment transport scale relations numerical modelling

Micro Electrical Discharge Machining Deposition in Air for Fabrication of Micro Spiral Structures

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chinese Journal of Mechanical Engineering 2010年第2期23卷 154-160页

作者： PENG Zilong chi Guanxin WANG Zhenlong Key Laboratory of Micro-Systems and Micro-Structures Manufacturing of Ministry of Education Harbin Institute of Technology Harbin 150001 China School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China

Micro electrical discharge machining（EDM） deposition process is a new micro machining method for fabrication of metal micro structures. In this process, the high level of tool electrode wear is used to achieve the metal material deposition. Up to now, the studies of micro EDM deposition process focused mainly on the researches of deposition process, namely the effects of discharge parameters in deposition process on the deposition rate or deposition quality. The research of the formation of micro structures with different discharge energy density still lacks. With proper conditions and only by the z-axis feeding in vertical direction, a novel shape of micro spiral structure can be deposited, with 0.11 mm in wire diameter, 0.20 mm in outside diameter, and 3.78 mm in height. Then some new deposition strategies including angular deposition and against the gravity deposition were also successful. In order to find the forming mechanism of the spiral structures, the numerical simulation of the transient temperature distribution on the discharge point was conducted by using the finite-element method（FEM）. The results show that there are two major factors lead to the forming of the spiral structures. One is the different material removal form of tool electrode according with the discharge energy density, the other is the influenced degree of the movement of the removed material particles in the discharge gap. The more the energy density in single discharge is, the smaller the mass of the removed material particles is, and the easier the movements of which will be changed to form an order tendency. The fine texture characteristics of the deposited micro spiral structures were analyzed by the energy spectrum analysis and the metallographic analysis. It shows that the components of the deposited material are almost the same as those of the tool electrode. Moreover the deposited material has the brass metallic luster in the longitudinal profile and has compact bonding with the

关键词： micro electrical discharge machining deposition micro spiral structure forming mechanism fine texture analysis

Necessary and Sufficient Conditions for Consensus in Third Order Multi-Agent Systems

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IEEE/CAA Journal of Automatica Sinica 2018年第6期5卷 1044-1053页

作者： chi Huang Guisheng Zhai Gesheng Xu College of Mathematics Taiyuan University of TechnologyTaiyuan 030024China Department of Mathematical Sciences Shibaura Institute of TechnologySaitama-337-8570Japan

We deal with a consensus control problem for a group of third order agents which are networked by *** that the control input of each agent is constructed based on weighted difference between its states and those of its neighbor agents, we aim to propose an algorithm on computing the weighting coefficients in the control input. The problem is reduced to designing Hurwitz polynomials with real or complex coefficients. We show that by using Hurwitz polynomials with complex coefficients, a necessary and sufficient condition can be obtained for designing the consensus algorithm. Since the condition is both necessary and sufficient, we provide a kind of parametrization for all the weighting coefficients achieving consensus. Moreover, the condition is a natural extension to second order consensus, and is reasonable and practical due to its comparatively decreased computation burden. The result is also extended to the case where communication delay exists in the control input.

关键词： Communication delay consensus algorithms,graph Laplacians Hurwitz polynomials third order multi-agent systems.

Consensus of cyber-physical power systems based on multi-agent systems with communication constraints

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Journal of Modern Power Systems and Clean Energy 2019年第5期7卷 1081-1093页

作者： chi HUANG Chengli FENG Jinde CAO School of Economic Information Engineering Southwestern University of Finance and EconomicsChengdu 611130China School of Mathematics Southeast UniversityNanjing 210096China College of Mathematics Taiyuan University of TechnologyTaiyuan 030024China

The consensus protocol of cyber-physical power systems is proposed based on fractional-order multi-agent systems with communication *** aims to enable each generator to reach a time-varying common rotor angle and rotor *** constraints including event-triggered sampling and partial information transmission are considered to render the consensus protocol more *** Zeno behavior is excluded during the system sampling process.A sufficient condition is derived to solve the consensus *** effectiveness of the proposed consensus protocol is demonstrated by a numerical example.

关键词： Cyber-physical power system Fractional-order system Multi-agent system Communication constraint

A study of influence of gravity on bulk behaviour of particulate solid

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Particuology 2008年第6期6卷 467-474页

作者： Yun-chi Chung Jin Yeam Ooi Department of Civil and Environmental Engineering Nanya Institute of Technology Institute for Infrastructure & Environment School of Engineering & Electronics University of Edinburgh

This paper examines the influence of gravity on the bulk responses of a granular solid. The loading scenarios in this study include confined compression, rod penetration into a granular medium and discharging through an orifice. Similar loading and flow conditions are likely to be encountered in the stress and deformation regimes that regoliths are subjected to in extraterrestrial exploration activities including in situ resource utilisation processes. Both spherical and non-spherical particles were studied using the discrete element method （DEM）. Whilst DEM is increasingly used to model granular solids, careful validations of the simulation outcomes are rather rare. Thus in addition to exploring the effect of gravity, this paper also compares DEM simulations with experiments under terrestrial condition to verify whether DEM can produce satisfactory predictions. The terrestrial experiments were conducted with great care and simulated closely using DEM. The key mechanical and geometrical properties for the particles were measured in laboratory tests for use in the DEM simulations. A series of DEM computations were then performed under reduced gravity to simulate these experiments under extraterrestrial environment. It was found that gravity has no noticeable effect on the force transmission in the confined compression case; the loading gradient in the rod penetration is linearly proportional to the gravity; the mass flow rate in silo discharge is proportional to square root of the gravity and the angle of repose increases with reducing gravity. These findings are in agreement with expectation and existing scientific evidence.

关键词： Extraterrestrial Particulate assembly Confined compression Rod penetration Silo discharge Discrete element method Gravity effect

Experimental characterization of the bipolar effect on P-hit single-event transients in 65 nm twin-well and triple-well CMOS technologies

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Science china(Technological Sciences) 2016年第3期59卷 488-493页

作者： CHEN JianJun LIANG Bin chi YaQing School of Computer National University of Defense Technology

Single-event charge collection is controlled by drift, diffusion and the bipolar effect. Previous work has established that the bipolar effect is significant in the p-type metal-oxide-semiconductor field-effect transistor(PMOS) in 90 nm technology and above. However, the consequences of the bipolar effect on P-hit single-event transients have still not completely been characterized in 65 nm technology. In this paper, characterization of the consequences of the bipolar effect on P-hit single-event transients is performed by heavy ion experiments in both 65 nm twin-well and triple-well complementary metal-oxide-semiconductor(CMOS) technologies. Two inverter chains with clever layout structures are explored for the characterization. Ge(linear energy transfer(LET) = 37.4 Me V cm^2/mg) and Ti(LET = 22.2 Me V cm^2/mg) particles are also employed. The experimental results show that with Ge(Ti) exposure, the average pulse reduction is 49 ps(45 ps) in triple-well CMOS technology and 42 ps(32 ps) in twin-well CMOS technology when the bipolar effect is efficiently mitigated. This characterization will provide an important reference for radiation hardening integrated circuit design.

关键词： single event transient (SET) bipolar effect quantitative characterization

Constellation shaping optimization for nonlinearity mitigation in CAP UVLC system

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Science china(Information Sciences) 2023年第9期66卷 274-290页

作者： Junlian JIA Junwen ZHANG Nan chi Key Laboratory for Information Science of Electromagnetic Waves(MoE) Fudan University Shanghai Engineering Research Center of Low-Earth-Orbit Satellite Communication and Applications Shanghai Collaborative Innovation Center of Low-Earth-Orbit Satellite Communication Technology Peng Cheng Laboratory

In the sixth-generation communication(6G), wireless communication will cover not only conventional air links but also underwater links. Underwater visible light communication(UVLC) is an expected technique that achieves a high data rate. However, UVLC systems suffer from severe nonlinear distortions for the high-power transmitting, thus nonlinear compensation is vital to the system. Carrier-less amplitude and phase(CAP) modulation is a promising modulation, especially for the scenes with high nonlinear *** this paper, for the first time, we proposed a constellation optimization method for the UVLC system supporting the native artificial intelligence in 6G. The proposed framework, based on the complete process of the CAP modulation and demodulation, fulfills an end-to-end learning scheme with a neural network at the transmitter side and the conventional demodulation processes at the receiver side. A loss function is further designed to support the training without needing a fixed signal-to-noise ratio(SNR). The proposed framework is simulated and then tested in an experiment. In a 1.2-meter nonlinear UVLC channel, compared with 1.5 Gbit/s supported by the conventional grid encoding, the proposed method brings an extra 200 Mbit/s data rate.

关键词： underwater visible light communication nonlinearity compensation constellation optimization