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Neural Regeneration Research 2025年第8期20卷 2169-2180页

作者： Mingyi yu Faith Teo En Ning Chang Liu yu-chi Liu Tissue Engineering and Stem Cell Group Singapore Eye Research InstituteSingapore Yong Loo Lin School of Medicine National University of SingaporeSingapore Department of Cornea and External Eye Disease Singapore National Eye CenterSingapore Ophthalmology and Visual Sciences Academic Clinical Program Duke-NUS Medical SchoolSingapore

Diabetic corneal neuropathy and diabetic retinopathy are ocular complications occurring in the context of diabetes *** corneal neuropathy refers to the progressive damage of corneal *** retinopathy has traditionally been considered as damage to the retinal ***,growing evidence suggests that diabetic retinopathy is a complex neurovascular disorder resulting from dysfunction of the neurovascular unit,which includes both the retinal vascular structures and neural *** retinopathy is one of the leading causes of blindness and is frequently screened for as part of diabetic ocular ***,diabetic corneal neuropathy is commonly overlooked and underdiagnosed,leading to severe ocular surface *** studies have found that these two conditions tend to occur together,and they share similarities in their pathogenesis pathways,being triggered by a status of chronic *** review aims to discuss the interconnection between diabetic corneal neuropathy and diabetic retinopathy,whether diabetic corneal neuropathy precedes diabetic retinopathy,as well as the relation between the stage of diabetic retinopathy and the severity of corneal *** also endeavor to explore the relevance of a corneal screening in diabetic eyes and the possibility of using corneal nerve measurements to monitor the progression of diabetic retinopathy.

关键词： cornea corneal nerves diabetes diabetic corneal neuropathy diabetic retinopathy retina

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

Fidelity spectrum:A tool to probe the property of a quantum phase

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chinese Physics B 2016年第3期25卷 84-90页

作者： Wing chi yu Shi-Jian Gu Department of Physics and ITR The Chinese University of Hong KongHong KongChina

Fidelity measures the similarity between two states and is widely adapted by the condensed matter community as a probe of quantum phase transitions in many-body systems. Despite its success in witnessing quantum critical points, information about the fine structure of a quantum phase one can get from this approach is still limited. Here, we proposed a scheme called fidelity spectrum, By studying the fidelity spectrum, one can obtain information about the characteristics of a phase. In particular, we investigated the spectra in the one-dimensional transverse-field Ising model and the two- dimensional Kitaev model on a honeycomb lattice. It was found that the sPectra have qualitative differences in the critical and non-critical regions of the two models. From the distributions of them, the dominating k modes in a particular phase could also be captured.

关键词： quantum phase.transitions quantum information quanfized spin models

A modest proposal for a new beginning: a Hippocratic Oath for S&T workers

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National Science Review 2015年第4期2卷 387-388页

作者： yu-chi Ho School of Engineering and Applied Sciences Harvard University

In the last 30 some years,chinese scientiic research has seen tremendous growth,along with the miraculous economic and social *** an oversea chinese scientist,I am very proud of the *** growths always come with some side issues that need to be addressed along the *** problem of scholarly misbehavior in china is well known and the systemic causes of the problem have also been extensively *** is no need for me to

关键词： A modest proposal for a new beginning a Hippocratic Oath for S&T workers

Computational fluid dynamics simulations of respiratory airflow in human nasal cavity and its characteristic dimension study

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Acta Mechanica Sinica 2008年第2期24卷 223-228页

作者： Jun Zhang Yingxi Liu Xiuzhen Sun Shen yu chi yu State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China Department of Otorhinolaryngology the Second Affiliated Hospital of Dalian Medical University Dalian 116027 China

To study the airflow distribution in human nasal cavity during respiration and the characteristic parameters of nasal structure, three-dimensional, anatomically accurate representations of 30 adult nasal cavity models were recons- tructed based on processed tomography images collected from normal people. The airflow fields in nasal cavities were simulated by fluid dynamics with finite element software ANSYS. The results showed that the difference of human nasal cavity structure led to different airflow distribution in the nasal cavities and variation of the main airstream passing through the common nasal meatus. The nasal resistance in the regions of nasal valve and nasal vestibule accounted for more than half of the overall resistance. The characteristic model of nasal cavity was extracted on the basis of characteristic points and dimensions deduced from the original models. It showed that either the geometric structure or the airflow field of the two kinds of models was similar. The characteristic dimensions were the characteristic parameters of nasal cavity that could properly represent the original model in model studies on nasal cavity.

关键词： Nasal cavity Characteristic dimension Three-dimensional reconstruction Numerical simulation of flowfield Computational fluid dynamic Finite element method

A Symbol Timing Recovery Algorithm of M-PSK Signals for Burst Modem Applications with Small Packet Size

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china Communications 2016年第6期13卷 138-146页

作者： yu chi Lan Chen Chao Lv Institute of Microelectronics Chinese Academy of Sciences

Feedforward symbol timing recovery techniques are particularly important for initial acquisition in burst modems. However, these techniques either have large calculation burden or sensitive to frequency offsets. In this paper, we proposed an efficient symbol timing recovery algorithm of MPSK signals named OMQ(Ordered Maximum power using Quadratic approximation partially) algorithm which is based on the Quadratic Approximation(QA) algorithm. We used ordered statistic sorting method to reduce the computational complexity further, meanwhile maximum mean power principle was used to decrease frequency offset sensitivity. The proposed algorithm adopts estimation-down sampling structure which is suitable for small packet size transmission. The results show that, while comparing with the QA algorithm, the computational complexity is reduced by 75% at most when 8 samples per symbol are used. The proposed algorithm shows better performance in terms of the jitter variance and sensitivity to frequency offsets.

关键词： symbol timing maximum mean power ordered statistic Quadratic Approximation

Short-term emergency response planning and risk assessment via an integrated modeling system for nuclear power plants in complex terrain

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Frontiers of Earth Science 2013年第1期7卷 1-27页

作者： Ni-Bin CHANG yu-chi WENG Department of Civil Environmental and Construction Engineering University of Central Florida Orlando FL 32816 USA Division of Environmental Engineering Graduate School of Engineering Hokkaido University Hokkaido Sapporo 060-8628 Japan

Short-term predictions of potential impacts from accidental release of various radionuclides at nuclear power plants are acutely needed, especially after the Fukushima accident in Japan. An integrated modeling system that provides expert services to assess the consequences of accidental or intentional releases of radioactive materials to the atmosphere has received wide attention. These scenarios can be initiated either by accident due to human, software, or mechanical failures, or from intentional acts such as sabotage and radioIogicaI dispersal devices. Stringent action might be required just minutes after the occurrence of accidental or intentional release. To fulfill the basic functions of emergency preparedness and response systems, previous studies seldom consider the suitability of air pollutant dispersion models or the connectivity between source term, disper- sion, and exposure assessment models in a holistic context for decision support. Therefore, the Gaussian plume and puff models, which are only suitable for illustrating neutral air pollutants in fiat terrain conditional to limited meteorological situations, are frequently used to predict the impact from accidental release of industrial sources. In situations with complex terrain or special meteorological conditions, the proposing emergency response actions might be questionable and even intractable to decision- makers responsible for maintaining public health and environmental quality. This study is a preliminary effort to integrate the source term, dispersion, and exposure assessment models into a Spatial Decision Support System （SDSS） to tackle the complex issues for short-term emergency response planning and risk assessment at nuclear power plants. Through a series model screening procedures, we found that the diagnostic （objective） wind field model with the aid of sufficient on-site meteorological monitoring data was the most applicable model to promptly address the trend of local wind field patt

关键词： emergency response nuclear power plants diagnostic model particle model source term model spatial analysis Spatial Decision Support System

N-doped NaTaO3 synthesized from a hydrothermal method for photocatalytic water splitting under visible light irradiation

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Journal of Energy Chemistry 2017年第3期26卷 515-521页

作者： Che-chia Hu Hui-Hsin Huang yu-chi Huang Department of Chemical Engineering and R&D Center for Membrane Technology Chung Yuan Christian UniversityTaoyuan City 32023TaiwanChina

NaTaONcatalysts were synthesized by a hydrothermal（H） and a solid-state（S） methods in this *** H-and S-NaTaONsamples were characterized by X-ray diffraction（XRD）, scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, UV–visible（UV–vis） diffuse reflectance spectroscopy, and photoluminescence（PL） spectroscopy. The XRD patterns of the H-and S-samples showed peaks indexed to the pure phase of perovskite NaTaOand minor peaks assignable to TaNat various synthesis temperatures. Substitution of oxygen by nitrogen ions causes the light absorption of the H-and S-NaTaONsamples to be extended to the 600–650 nm region, thus making the samples visible-light active. The NaTaONsamples exhibited photocatalytic activity for Hand Oevolution from aqueous methanol and silver nitrate solutions under visible-light irradiation. The UV–vis and PL spectra of the Hand S-catalysts revealed the presence of cationic vacancies and reduced metallic species, which acted as recombination centers. These results demonstrated that the preparation method plays a critical role in the formation of defect states, thereby governing the photocatalytic activity of the NaTaONcatalysts.

关键词： Photocatalysis H2 production N-doped NaTaO3 Hydrothermal method Visible light

Modifying and Reducing Numerical Dissipation in A Two-Dimensional Central-Upwind Scheme

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Advances in Applied Mathematics and Mechanics 2012年第3期4卷 340-353页

作者： chi-Jer yu chii-Tung Liu Department of Applied Mathematics National Chiao Tung University1001 University RoadHsinchu 300Taiwan Department of Computer Science and Information Engineering Chaoyang University of Technology168 Jifong E.Rd.Wufong Township Taichung County 41349Taiwan

This study presents a modification of the central-upwind Kurganov scheme for approximating the solution of the 2D Euler *** prototype,extended from a 1D model,reduces substantially less dissipation than *** problem arises from over-restriction of some slope limiters,which keep slopes between interfaces of cells to be *** study reports the defect and presents a re-derived optimal *** experiments highlight the significance of this formula,especially in long-time,large-scale simulations.

关键词： Hyperbolic systems of conservation laws Godunov-type finite-volume methods central-upwind scheme Kurganov numerical dissipation anti-diffusion

Study on hydrodynamic vibration in fluidic flowmeter

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第9期8卷 1422-1428页

作者： WANG chi-yu ZOU Jun FU Xin YANG Hua-yong Institute State Key Laboratory of Fluid Power Transmission amt Control Zhejiang University Hangzhou 310027 China

The characteristics of the fluidic flowmeter,which is a combination of impinged concave wall and bistable fluid amplifier,is investigated by experimental studies and numerical simulations. The numerical approaches are utilized to examine the time dependent flow field and pressure field inside the proposed flowmeter. The effect of varying structural parameters on flow characteristics of the proposed fluidic flowmeter is investigated by computational simulations for the optimization. Both the simulation and experimental results disclose that the hydrodynamic vibration,with the same intensity,frequency and 180° phase shift,occurs at axisymmetric points in the feedback channel of the fluidic flowmeter. Using the structural combination of impinged concave wall and bistable fluid amplifier and differential signal processing technique,a novel fluidic flowmeter with excellent immunity and improved sensibility is developed.

关键词： Flowmeter Fluidic Hydrodynamic vibration Coanda effect