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A simple and rapid simultaneous measurement strategy for optical rotatory dispersion and circular dichroism

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Light(Science & Applications) 2024年第11期13卷 2431-2433页

作者： Junjie du State Key Laboratory of Precision Spectroscopy School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200062China

A simple cavity-based technology capable of simultaneously measuring optical rotary dispersion and circular dichroism within milliseconds offers ultra-high sensitivity and unprecedented spectral *** advancement holds significant potential for various biochemical applications,including drug development,clinical diagnosis,and food science and safety.

关键词： dispersion circular simultaneous

Frequency Weighting Filter Design for Automotive Ride Comfort Evaluation

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Chinese Journal of Mechanical Engineering 2016年第4期29卷 727-738页

作者： du Feng School of Mechanical and Automotive Engineering South China University of Technology

Few study gives guidance to design weighting filters according to the frequency weighting factors,and the additional evaluation method of automotive ride comfort is not made good use of in some *** on the regularities of the weighting factors,a method is proposed and the vertical and horizontal weighting filters are *** whole frequency range is divided several times into two parts with respective *** each division,a parallel filter constituted by a low-and a high-pass filter with the same cutoff frequency and the quality factor is utilized to achieve section *** cascading of these parallel filters obtains entire *** filters own a high ***,low order filters are preferred in some *** bilinear transformation method and the least P-norm optimal infinite impulse response（IIR） filter design method are employed to develop low order filters to approximate the weightings in the *** addition,with the window method,the linear phase finite impulse response（FIR） filter is designed to keep the signal from distorting and to obtain the staircase *** the same case,the traditional method produces 0.330 7 m · s^–2 weighted root mean square（r.m.s.） acceleration and the filtering method gives 0.311 9 m · s^–2 *** fourth order filter for approximation of vertical weighting obtains 0.313 9 m · s^–2 *** factors of the acceleration signal weighted by the weighting filter and the fourth order filter are 3.002 7 and 3.011 1,*** paper proposes several methods to design frequency weighting filters for automotive ride comfort evaluation,and these developed weighting filters are effective.

关键词： frequency weighting ride comfort evaluation least P-norm optimal method bilinear transformation weighting filter design

栅极几何结构对MIS栅结构常关p-GaN/AlGaN/GaN HEMTs性能的影响

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沈阳理工大学学报 2025年第1期44卷 72-77页

作者：都继瑶沈阳理工大学自动化与电气工程学院沈阳110159 沈阳理工大学科技开发总公司沈阳110013

高电子迁移率晶体管(high electron mobility transistors,HEMTs)具有高速开关和极高击穿电场等特性,在功率器件领域应用广泛。为提高HEMT器件性能,通过实验研究了栅极几何结构对具有金属/绝缘体/半导体(MIS)栅极结构的常关型p-GaN/AlGa... 详细信息

高电子迁移率晶体管(high electron mobility transistors,HEMTs)具有高速开关和极高击穿电场等特性,在功率器件领域应用广泛。为提高HEMT器件性能,通过实验研究了栅极几何结构对具有金属/绝缘体/半导体(MIS)栅极结构的常关型p-GaN/AlGaN/GaN HEMTs性能的影响。栅极介质层采用5 nm厚的原位生长AlN,AlN/p-GaN界面呈现出更明显的能带弯曲和更宽的耗尽区,有利于阈值电压向正向偏移,且其相对较宽的能带错位有助于抑制栅极电流。实验结果表明:与栅极非覆盖区长度为0μm和6μm的MIS栅极相比,非覆盖区长度为3μm的MIS栅极可提高器件综合性能,有效抑制正向栅极电流,将阈值电压提高至3 V,并较好地保持电流密度为46 mA/mm;栅极结构中两侧没有栅极覆盖的区域在导通过程和导通状态下均可引起较大的沟道电阻,且沟道电阻随着非覆盖区长度增加而上升。

关键词： p-GaN/AlGaN/GaN异质结 AlN介质层常关型器件金属/绝缘体/半导体栅极非覆盖区

Global Land Surface Climate Analysis Based on the Calculation of a Modified Bowen Ratio

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Advances in Atmospheric Sciences 2017年第5期34卷 663-678页

作者： Bo HAN Shihua Lü Ruiqing LI Xin WANG Lin ZHAO cailing ZHAO Danyun WANG Xianhong MENG Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China College of Atmospheric Sciences Chengdu University of Information Technology Plateau Atmosphere and Environment Key Laboratory of Sichuan Province Chengdu 610225 China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology Nanjing 210044 China Inner Mongolia Autonomous Regional Meteorological Observatory Hohhot 010051 China Institute of Arid Meteorology China Meteorological Administration Lanzhou 730020 China

A modified Bowen ratio(BRm),the sign of which is determined by the direction of the surface sensible heat flux,was used to represent the major divisions in climate across the globe,and the usefulness of this approach was evaluated. Five reanalysis datasets and the results of an offline land surface model were investigated. We divided the global continents into five major BRm zones using the climatological means of the sensible and latent heat fluxes during the period 1980–2010:extremely cold,extremely wet,semi-wet,semi-arid and extremely arid. These zones had BRm ranges of(-∞,0),(0,0.5),(0.5,2),(2,10) and(10,+∞),respectively. The climatological mean distribution of the Bowen ratio zones corresponded well with the K ¨oppen-like climate classification,and it reflected well the seasonal variation for each subdivision of climate classification. The features of climate change over the mean climatological BRm zones were also investigated. In addition to giving a map-like classification of climate,the BRm also reflects temporal variations in different climatic zones based on land surface processes. An investigation of the coverage of the BRm zones showed that the extremely wet and extremely arid regions expanded,whereas a reduction in area was seen for the semi-wet and semi-arid regions in boreal spring during the period 1980–2010. This indicates that the arid regions may have become drier and the wet regions wetter over this period of time.

关键词： climate classification surface turbulent heat flux climate change

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孤岛工作面沿空掘巷窄煤柱承载特征研究

煤矿现代化 2025年第1期34卷 19-24页

作者：杜怀飞山西煤炭运销集团金辛达煤业有限公司山西临汾041000

孤岛工作面复杂的支承压力分布状态致使沿空巷道的围岩稳定性受到了极大影响。为探究孤岛工作面沿空掘巷窄煤柱承载特征,采用理论分析方法探究了煤柱塑性区宽度与多种因素相关性,运用数值模拟方法分析了支护参数对巷道围岩稳定性的影响... 详细信息

孤岛工作面复杂的支承压力分布状态致使沿空巷道的围岩稳定性受到了极大影响。为探究孤岛工作面沿空掘巷窄煤柱承载特征,采用理论分析方法探究了煤柱塑性区宽度与多种因素相关性,运用数值模拟方法分析了支护参数对巷道围岩稳定性的影响。研究表明:随着侧压系数的增加,塑性区宽度近似线性增加;而随着支护强度的增加,塑性区宽度则近似线性减小。凝聚力和摩擦角的增加均会导致塑性区宽度的减小,但减小的幅度逐渐变小。增加锚杆长度和预紧力可以扩大压动范围,有效控制巷道围岩变形;而间排距的调整需要在保证支护强度的前提下,选择适当的宽度以提高施工效率和经济性。通过工业实验,采用合理的煤柱宽度和支护结构后,巷道围岩变形趋于稳定,确保了巷道的安全与正常使用,验证了支护方案的有效性。

关键词：支护强度压动范围侧压系数数值模拟

Efficient photo-assisted Fenton oxidation treatment of multi-walled carbon nanotubes

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Chinese Science Bulletin 2007年第15期52卷 2054-2062页

作者： FAN cailing LI Wei LI Xin ZHAO ShiJu ZHANG Ling MO YuJun CHENG RongMing College of Science Henan Agricultural University Zhengzhou 450002 China School of Physics and Information Photoelectron Henan University Kaifeng 475001 China Center of Functional Nanomaterials and Devices East China Normal University Shanghai 200062 China

In this paper,a new and efficient way to oxidize and functionalize the multi-walled carbon nanotubes (MWNTs) has been developed by using a combination of ultraviolet (UV) irradiation and Fenton oxida-tion process,namely UV/Fenton oxidation treatment. Comparing with conventionally individual Fenton oxidation treatment of MWNTs,UV/Fenton combined treatment improved the etching rates and effi-ciencies and hence reduced the time for surface modification of MWNTs,which was proved to be an effective method in etching and functionalizing CNTs. The formation of new functional groups,struc-tural changes and thermal stability during oxidation period were characterized by Fourier transform infrared spectroscopy (FTIR),Raman spectroscopy and could be clarified by thermogravimetric analy-sis (TGA),which showed that it was under UV irradiation conditions that MWNTs could be rapidly functionalized with hydroxyl,carbonyl and carboxyl groups in the presence of Fenton reagents,origi-nating from the increase in the gross HO· concentration and the existent synergetic effect when using UV irradiation combing with Fenton oxidation process. Introduction of such new oxygen-containing functional groups was attributed to attacks of HO· on defect sites and unsaturated bonds of C=C in the MWNTs sample,which should play an important role in accounting for the FTIR and Raman spectral changes.

关键词：碳纳米管氧化处理紫外线辐射表面修饰

InAs/(In)GaSb-superconductor heterostructures:Materials and devices

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Science China(Physics,Mechanics & Astronomy) 2023年第6期66卷 74-85页

作者： Rui-Rui du International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China

This article will briefly describe a Majorana platform made of InAs/GaSb(including InAs/(In)GaSb)semiconductor-superconductor heterostructures.A unique advantage of this platform is that the quantum spin Hall edge state realized in inverted InAs/GaSb is a topologically protected spinless single mode,and can be tuned by front-back dual *** to a number of other platforms the proximity effect of a conventional s-wave superconductor on the helical edge has been proposed to realize Majorana bound *** will present an introduction to this platform with a focus on the materials and devices aspects and those points that are particularly illustrative.

关键词： topological insulators heterostructures topological superconductivity molecular beam epitaxy electrical transport

负载槲皮素的羧甲基壳聚糖水凝胶促进糖尿病大鼠创面愈合

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中国组织工程研究 2025年第4期29卷 692-699页

作者：董美林都海宇刘源连云港市第二人民医院(南京医科大学康达学院附属医院)烧伤整形科江苏省连云港市222000

背景:槲皮素具有抗炎、抗癌、抗氧化、抗衰老、抗抑郁等药理作用,具有极高的药用价值。槲皮素可以促进正常大鼠创面的愈合,但是以槲皮素为主要成分的药物研发较少,限制了其在临床的广泛应用。目的:以水凝胶材料负载槲皮素,探讨槲皮素-... 详细信息

背景:槲皮素具有抗炎、抗癌、抗氧化、抗衰老、抗抑郁等药理作用,具有极高的药用价值。槲皮素可以促进正常大鼠创面的愈合,但是以槲皮素为主要成分的药物研发较少,限制了其在临床的广泛应用。目的:以水凝胶材料负载槲皮素,探讨槲皮素-羧甲基壳聚糖水凝胶在糖尿病大鼠创面中的应用效果。方法:①分别制备羧甲基壳聚糖水凝胶与槲皮素-羧甲基壳聚糖水凝胶,表征水凝胶的微观形貌、体外释药性能。②细胞实验:将小鼠L929成纤维细胞分4组培养,空白对照组常规培养,纯水凝胶组、药物组、载药水凝胶组分别加入羧甲基壳聚糖水凝胶、槲皮素溶液与槲皮素-羧甲基壳聚糖水凝胶,检测细胞增殖与迁移能力。③动物实验:取80只SD大鼠建立糖尿病模型,造模成功后在大鼠背部制作直径2 cm的全层皮肤缺损创面,随机分4组干预,空白对照组、纯水凝胶组、药物组、载药水凝胶组创面分别注射生理盐水、羧甲基壳聚糖水凝胶、槲皮素溶液、槲皮素-羧甲基壳聚糖水凝胶,每组20只,无菌纱布包扎固定。术后观察创面愈合情况、创面病理形态、炎症因子表达及血管生成情况。结果与结论:①扫描电镜下可见两种水凝胶的微观形貌相似,均呈疏松多孔的网络结构,并且槲皮素-羧甲基壳聚糖水凝胶具有良好的体外释药性能。②与空白对照组比较,其他3组细胞增殖与迁移率升高(P<0.05);载药水凝胶组细胞增殖与迁移率高于纯水凝胶组、药物组(P<0.05)。③载药水凝胶组大鼠术后5,11 d的创面愈合率高于其他3组;载药水凝胶组、纯水凝胶组、药物组大鼠术后18 d的创面愈合率基本达到100%,均高于空白对照组(P<0.05)。苏木精-伊红染色显示,载药水凝胶组大鼠术后18 d创面可见完整的皮肤与皮肤附属器,空白对照组、纯水凝胶组、药物组大鼠术后25 d创面可见完整的皮肤与皮肤附属器。载药水凝胶组大鼠创面术后5,11,18 d的创面肿瘤坏死因子α、白细胞介素6水平均低于空白对照组(P<0.05),术后11,18 d的创面转化生长因子β1水平低于空白对照组(P<0.05)。载药水凝胶组大鼠术后11,18 d的CD31、血管内皮生长因子αmRNA表达量均高于其他3组(P<0.05)。④结果表明,槲皮素-羧甲基壳聚糖水凝胶中的槲皮素可发挥调节炎症反应、促进血管新生的作用,可通过促进成纤维细胞的增殖与迁移,促进糖尿病大鼠创面的愈合。

关键词：创面愈合槲皮素敷料水凝胶糖尿病创面羧甲基壳聚糖皮肤创面成纤维细胞

The detection, extraction and parameter estimation of extreme-mass-ratio inspirals with deep learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 86-96页

作者： Qianyun Yun Wen-Biao Han Yi-Yang Guo He Wang Minghui du Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Shanghai Astronomical Observatory Chinese Academy of Sciences School of Physics and Astronomy Shanghai Jiao Tong University School of Astronomy and Space Science University of Chinese Academy of Sciences Taiji Laboratory for Gravitational Wave Universe (Beijing/Hangzhou) University of Chinese Academy of Sciences Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Province Key Laboratory of Quantum Theory and Applications of MoE Lanzhou University Institute of Theoretical Physics & Research Center of Gravitation Lanzhou University International Centre for Theoretical Physics Asia-Pacific (ICTP-AP) University of Chinese Academy of Sciences (UCAS) Center for Gravitational Wave Experiment National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences

One of the primary goals of space-borne gravitational wave detectors is to detect and analyze extreme-mass-ratio inspirals(EMRIs). This task is particularly challenging because EMRI signals are complex, lengthy, and faint. In this work, we introduce a2-layer convolutional neural network(CNN) approach to detect EMRI signals for space-borne detectors, achieving a true positive rate(TPR) of 96.9% at a 1% false positive rate(FPR) for signal-to-noise ratio(SNR) from 50 to 100. Especially, the key intrinsic parameters of EMRIs such as the mass, spin of the supermassive black hole(SMBH) and the initial eccentricity of the orbit can also be inferred directly by employing a neural network. The mass and spin of the SMBH can be determined at 99% and 92% respectively. This will greatly reduce the parameter spaces and computing cost for the following Bayesian parameter *** model also has a low dependency on the accuracy of the waveform model. This study underscores the potential of deep learning methods in EMRI data analysis, enabling the rapid detection of EMRI signals and efficient parameter estimation.

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