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Reflectivity of W/Si Multilayer at the Photo-energies of 700eV and 1200eV

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Chinese Physics Letters 2001年第11期18卷 1481-1482页

作者： feng shi-meng ZHU Guo-Long SHAO Jian-Da YI Kui FAN Zheng-Xiu Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesP.O.Box 800-211Shanghai 201800

We have deposited W/Si multilayer mirrors using magnetron sputtering, and measured their reflectivity at the Beijing Synchrotron Radiation Facility. The W/Si multilayer mirrors show a peak reflectivity of approximately 10% at a photo-energy of 1200eV and 10.5% at a photo-energy of 700eV at an incidence angle of 81°. So far, no higher reflectivity than that given in this letter has been reported.

关键词： reflectivity multilayer letter

Selective leaching of calcium from mechanically activated mixed rare earth concentrate

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Journal of Rare Earths 2024年第6期42卷 1149-1156,I0006页

作者： Jiang Liu Bingxue Chen Yuanqi feng Yijun Cao Yukun Huang Yuan shi meng Li Zhongyuan Critical Metals Laboratory School of Chemical EngineeringZhengzhou UniversityZhengzhou450001China State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou730050China

The loss of rare earths(REs)takes place during the pre-decalcification process of mixed rare earth *** an effort to reduce such RE loss,a novel idea to improve the leaching selectivity of Ca to REs by applying selective mechanical activation was ***,regarding the key minerals affecting the leaching selectivity of Ca to REs,the differences in the mechanical activation behaviors of CaF_(2) and REFCO_(3) were studied,and we find that the lattice strain of CaF_(2) increases from 0.21%to 0.42%,whereas that of REFCO_(3) increases from 0.31%to 0.40%.Notably,CaF_(2) demonstrates a larger lattice strain than REFCO_(3),indicating greater mechanical activation energy storage and higher leaching ***,the HCl leaching process was studied.A significant leaching selectivity of Ca to REs,from 21.6 to 35.1,is achieved through mechanical *** Ca leaching rate reaches 80.7%when the RE loss is 2.3%in the activated *** study provides an novel approach for achieving selective extraction of specific components via mechanical activation pretreatment.

关键词： Mixed rare earth concentrate Pre-decalcification Selective mechanical activation Selective leaching

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复指数矩阵法研究螺旋液晶光学传播特性

光学学报 2008年第9期28卷 1805-1811页

作者：陈婷冯仕猛上海交通大学物理系上海200240

提出一种研究螺旋液晶光学特性的数学处理方法。螺旋型液晶可当作N层双折射材料晶片叠合而成,而相邻晶片的光轴依次旋转一个小角度。在光学转换矩阵中引入复数来研究螺旋型液晶光学性能,给出了相关的数学处理方法。研究了线性偏振光在... 详细信息

提出一种研究螺旋液晶光学特性的数学处理方法。螺旋型液晶可当作N层双折射材料晶片叠合而成,而相邻晶片的光轴依次旋转一个小角度。在光学转换矩阵中引入复数来研究螺旋型液晶光学性能,给出了相关的数学处理方法。研究了线性偏振光在螺旋液晶中的传播特性,并给出了光经过螺旋液晶后电场强度的矩阵表达式。研究发现,如果入射光波长等于螺旋液晶螺距,线偏振光经过右螺旋液晶后是左旋圆偏振光。理论上分析了螺旋液晶对可见光选择性反射机理。

关键词：螺旋液晶指数矩阵旋光器件偏振光

Biomimetic chitin hydrogel via chemical transformation

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Nano Research 2024年第2期17卷 771-777页

作者： Rui-Rui Liu Qian-Qian shi Yu-feng meng Yong Zhou Li-Bo Mao Shu-Hong Yu Division of Nanomaterials&Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China College&Hospital of Stomatology Key Laboratory of Oral Diseases Research of Anhui ProvinceAnhui Medical UniversityHefei 230032China Department of Dental Implantology College&Hospital of StomatologyAnhui Medical UniversityHefei 230032China

Chitin hydrogel has been recognized as a promising material for various biomedical applications because of its biocompatibility and ***,the fabrication of strong chitin hydrogel remains a big challenge because of the insolubility of chitin in many solvents and the reduced chain length of chitin regenerated from *** herein introduce the fabrication of chitin hydrogel with biomimetic structure through the chemical transformation of chitosan,which is a water-soluble deacetylated derivative of *** reacetylation of the amino group in chitosan endows the obtained chitin hydrogel with outstanding resistance to swelling,degradation,extreme temperature and pH conditions,and organic *** chitin hydrogel has excellent mechanical properties while retaining a high water content(more than 95 wt.%).It also shows excellent antifouling performance that it resists the adhesion of proteins,bacteria,blood,and ***,as the initial chitosan solution can be feasibly frozen and templated by ice crystals,the chitin hydrogel structure can be either nacre-like or wood-like depending on the freezing method of the precursory chitosan *** to these anisotropic structures,such chitin hydrogel can exhibit anisotropic mechanics and mass transfer *** current work provides a rational strategy to fabricate chitin hydrogels and paves the way for its practical applications as a superior biomedical material.

关键词： chitin hydrogel biomimetic structure chemical stability mechanical strength antifouling

Fast nuclear-spin gates and electrons−nuclei entanglement of neutral atoms in weak magnetic fields

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Frontiers of physics 2024年第2期19卷 179-203页

作者： Xiao-feng shi School of Physics Xidian UniversityXi’an 710071China

We present a novel class of Rydberg-mediated nuclear-spin entanglement in divalent atoms with global laser ***,we show a fast nuclear-spin controlled phase gate of an arbitrary phase realizable either with two laser pulses when assisted by Stark shifts,or with three ***,we propose to create an electrons−nuclei-entangled state,which is named a super bell state(SBS)for it mimics a large Bell state incorporating three small Bell ***,we show a protocol to create a three-atom electrons-nuclei entangled state which contains the three-body W and Greenberger−Horne−Zeilinger(GHZ)states *** protocols possess high intrinsic fidelities,do not require single-site Rydberg addressing,and can be executed with large Rydberg Rabi frequencies in a weak,Gauss-scale magnetic *** latter two protocols can enable measurement-based preparation of Bell,hyperentangled,and GHZ states,and,specifically,SBS can enable quantum dense coding where one can share three classical bits of information by sending one particle.

关键词： nuclear-spin qubit electrons−nuclei entanglement super Bell state Greenberger−Horne−Zeilinger state Rydberg-mediated entanglement quantum dense coding

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弱磁场中向列相液晶的磁光效应

光学学报 2009年第2期29卷 443-447页

作者：陈婷冯仕猛上海交通大学物理系上海200240

当外磁场强度比较小时,液晶不会发生Freedericksz转变。利用介电张量分析了扭曲型向列液晶在弱磁场中的旋光效应。通过理论分析表明,线性偏振光经过磁场中的扭曲型向列液晶,会产生左右两束椭圆偏振光。这两束椭圆偏振光在该液晶中的传... 详细信息

当外磁场强度比较小时,液晶不会发生Freedericksz转变。利用介电张量分析了扭曲型向列液晶在弱磁场中的旋光效应。通过理论分析表明,线性偏振光经过磁场中的扭曲型向列液晶,会产生左右两束椭圆偏振光。这两束椭圆偏振光在该液晶中的传播速度不同,导致光经过液晶盒后光电场振动面发生偏转。进一步分析表明,对于同一种波长的光,磁场强度越大,其电场振动面旋转角度越大。在相同的磁场强度下,光波长越短,其电场振动面旋转角度越大。如果加上高的偏置电压,使向列型液晶分子长轴方向与外磁场方向平行,线性偏振光经过磁场中的该扭曲型向列液晶,其振动面会也发生偏转。

关键词：材料液晶磁场旋光效应

Semi-volatile organic compounds in a museum in China:A non-targeted screening approach

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Science China(Technological Sciences) 2024年第9期67卷 2693-2705页

作者： SONG ZiDong NIAN LuYing shi meng REN XiaoPeng TANG Ming shi AnMei HAN Ying LIU Min WANG LuYang ZHANG YinPing XU Ying feng Xiaomeng Department of Building Science Tsinghua UniversityBeijing 100084China Beijing Key Laboratory of Indoor Air Quality Evaluation and Control Beijing 100084China National Museum of China Beijing 100006China Department of Endocrinology Beijing Chao-Yang HospitalCapital Medical UniversityBeijing 100020China

Non-targeted analysis(NTA)was conducted to identify semi-volatile organic compounds(SVOCs)in a museum in China using the gas chromatography(GC)-Orbitrap-mass spectrometer(MS).Approximately 160 SVOCs were detected,of which 93 had not been reported in previous studies of museum *** of the detected SVOCs were found to be associated with the chemical agents applied in conservation treatment and the materials used in *** results of hierarchical cluster analysis(HCA)indicated a spatial variation of SVOCs in the indoor air in the museum,but there were no obvious temporal differences of SVOCs observed in indoor ***'s correlation analysis showed that several classes of SVOCs were well correlated,suggesting their common *** and plasticizers were found to be the primary sources of SVOC pollution detected in the *** with compounds in outdoor air,indoor SVOCs had a lower level of unsaturation and more portions of chemically reduced *** study is the first of its kind to comprehensively characterize SVOCs in a museum using an automated NTA approach with *** SVOCs identified in the current study are likely to be present in other similar museums;therefore,further examination of their potential impacts on cultural heritage artifacts,museum personnel,and visitors may be warranted.

关键词： non-target analysis high-resolution mass spectrometry semi-volatile organic compounds museum environment air pollutants

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Attractor for the Extensible Beam Equation with Nonlocal Weak Damping on Time–Dependent Space

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1115-1126页

作者： Chun Xiang ZHAO feng Juan meng Institute of Applied System Analysis Jiangsu UniversityZhenjiang 212013P.R.China School of Mathematics and Physics Jiangsu University of TechnologyChangzhou 213001P.R.China

In this article,we consider the long-time behavior of extensible beams with nonlocal weak damping:ε(t)u_(tt)+Δ^(2)u-m(‖▽u‖^(2))Δu+‖u_(t)‖^(p_(u_(t)))+f(u)=h,whereε(t)is a decreasing function vanishing at *** the theory of process on time-dependent spaces,we investigate the existence of the time-dependent attractor by using the Condition(C_(t))method and more detailed *** results obtained essentially improve and complete some previous works.

关键词： Time-dependent attractor extensible beams equation nonlocal weak damping

Covariate-Assisted Matrix Completion with Multiple Structural Breaks

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Journal of Systems Science & Complexity 2024年第2期37卷 692-728页

作者： meng Jing feng Long ZOU Changliang WANG Zhaojun School of Statistics and Data Science KLMDASRLEBPSand LPMCNankai UniversityTianjin 300071China

In matrix completion,additional covariates often provide valuable information for completing the unobserved entries of a high-dimensional low-rank matrix *** this paper,the authors consider the matrix recovery problem when there are multiple structural breaks in the coefficient matrix β under the column-space-decomposition model A=Xβ+B.A cumulative sum(CUSUM)statistic is constructed based on the penalized estimation of β.Then the CUSUM is incorporated into the Wild Binary Segmentation(WBS)algorithm to consistently estimate the location of ***,a nearly-optimal recovery of A is *** findings are further corroborated via numerical experiments and a real-data application.

关键词： Additional covariates matrix completion multiple structural breaks wild Binary Segmentation