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Light(Science & Applications) 2024年第9期13卷 1878-1887页

作者： yang Lu xu Zhao Dongmei yan Yingqian Mi Peng Sun xu yan Xiaomin Liu Geyu Lu State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin University130012 ChangchunChina Department of Immunology College of Basic Medical SciencesJilin University130021 ChangchunChina

Chiral assemblies have become one of the most active research areas due to their versatility,playing an increasingly important role in bio-detection,imaging and *** this work,chiral UCNPs/CuxOS@ZIF nanoprobes are prepared by encapsulating upconversion nanoparticles(UCNPs)and CuxOS nanoparticles(NPs)into zeolitic imidazolate framework-8(ZIF-8).The novel excited-state energy distribution-modulated upconversion nanostructure(NaYbF4@-NaYF4:Yb,Er)is selected as the fluorescence source and energy donor for highly efficient fluorescence resonance energy transfer(FRET).CuxOS NP is employed as chiral source and energy acceptor to quench upconversion luminescence(UCL)and provide circular dichroism(CD)*** the natural adsorption and sorting advantages of ZIF-8,the designed nanoprobe can isolate the influence of other common disruptors,thus achieve ultra-sensitive and highly selective UCL/CD dual-mode quantification of H2S in aqueous solution and in living ***,the nanoprobe is also capable of in vivo intra-tumoral H2S *** work highlights the multifunctional properties of chiral nanocomposites in sensing and opens a new vision and idea for the preparation and application of chiral nanomaterials in biomedical and biological analysis.

关键词： chiral sulfide donor

Magnetic responsive scaffolds and magnetic fields in bone repair and regeneration

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Frontiers of Materials Science 2014年第1期8卷 20-31页

作者： Hai-yan xu Ning GU Department of Biomedical Engineering Institute of Basic Medical Sciences Chinese Academy of Medical Science & Peking Union Medical College Beijing 100005 China State Key Laboratory of Bioelectronics and Jiangsu Key Laboratory for Biomaterials and Devices School of Biological Science & Medical Engineering Southeast University Nanjing 210096 China

Increasing evidence shows that magnetic fields and magnetic responsive scaffolds can play unique roles in promoting bone repair and regeneration. This article addresses the synergistic effects of magnetic scaffolds in response to external magnetic fields on the bone regeneration in situ. Additionally, the exploration of using magnetic scaffolds as tools in the bone implant fixation, local drug delivery and mimicking microenvironment of stem cell differentiation are introduced. We also discussed possible underlying mechanisms and perspectives of magnetic responsive scaffolds in the bone repair and regeneration.

关键词： bone repair magnetic scaffold magnetic field physical stimulation

DISSIPATIVE NUMERICAL METHODS FOR THE HUNTER-SAXTON EQUATION

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Journal of Computational Mathematics 2010年第5期28卷 606-620页

作者： yan xu Chi-Wang Shu Department of Mathematics University of Science and Technology of China Hefei 230026 China Division of Applied Mathematics Brown University Providence RI 02912 USA

In this paper, we present further development of the local discontinuous Galerkin （LDG） method designed in [21] and a new dissipative discontinuous Galerkin （DG） method for the HuntermSaxton equation. The numerical fluxes for the LDG and DG methods in this paper are based on the upwinding principle. The resulting schemes provide additional energy dissipation and better control of numerical oscillations near derivative singularities. Stability and convergence of the schemes are proved theoretically, and numerical simulation results are provided to compare with the scheme in [21].

关键词： Discontinuous Galerkin method Local discontinuous Galerkin method dissi-pation Hunter-Saxton equation Stability.

Synthesis and Structure of an Interlock Network Frame of Cobalt(Ⅱ) Coordination Polymer {[Co(azpy)_2(NCS)_2]·1/4EtOH·1/2H_2O}_n (azpy=4,4′-Azobispyridine)

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Chemical Research in Chinese Universities 2001年第3期17卷 237-242页

作者： LI Bao-long xu yan LIU Yong-jiang xu Zheng Coordination Chemistry Institute State Key Laboratory of Coordination ChemistryNanjing UniversityNanfing 210093P.R.China

A compound {[Co(azpy)2(NCS)2]·1/4EtOH·1/2H2O}n(1), where azpy=4,4’-azobispyridine, was synthesized and characterized by means of IR, TGA-DTA, magnetic susceptibility and X-ray single crystal diffraction. It consists of two independent sets of fully interlocked two-dimensional networks with the dihedral angle 61.7°, organized in parallel stacks of the sheets which are made of edge-shared [Co(Ⅱ)]4squares separated by 0. 9062nm, and defined size rhombic channels. The thermal gravimetric analysis indicates that the framework is stable up to 198℃. The variable-temperature magnetic susceptibility measurements indicated that there is a weak antiferromagnetic interaction between the cobalt(Ⅰ) ions in the complex (1).

关键词： Crystal structure Porous structure Cobalt complex Azobispyridine complex Thiocyanate complex

基于三周期极小曲面晶胞梯度支架的设计及力学性能

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中国组织工程研究 2025年第16期29卷 3449-3457页

作者：朱文博张旭婧许燕石欣桐新疆大学智能制造现代产业学院(机械工程学院) 新疆维吾尔自治区乌鲁木齐市830046

背景:现阶段骨软骨一体化支架的弹性模量与天然骨软骨相差较大,植入人体后会引起应力遮蔽现象,从而导致植入物松动变形,影响骨软骨组织修复。轴向三周期极小曲面晶胞梯度支架可与人体骨软骨组织孔隙率及弹性模量相匹配,为骨软骨支架设... 详细信息

背景:现阶段骨软骨一体化支架的弹性模量与天然骨软骨相差较大,植入人体后会引起应力遮蔽现象,从而导致植入物松动变形,影响骨软骨组织修复。轴向三周期极小曲面晶胞梯度支架可与人体骨软骨组织孔隙率及弹性模量相匹配,为骨软骨支架设计提供一种新的思路。目的:研究不同晶胞种类和孔径结构对晶胞梯度支架力学性能的影响。方法:使用Gyroid(G)型、Diamond(D)型Primitive(P)型3种基础晶胞,通过三周期极小曲面数学建模,在梯度区域使用不同尺寸、不同种类晶胞,共计构建6种晶胞梯度支架(G-2P-4D、P-2D-4G、D-2P-4D、G-2D-4P、P-2G-4D、D-2G-4P),进行力学实验及仿真模拟实验,评估支架的力学性能,通过计算流体动力学仿真得到了支架内流体的流动性能参数。结果与结论:有限元力学仿真和轴向压缩实验表明,P-2G-4D型与P-2D-4G型梯度支架的弹性模量相较高,分别为148.67 MPa和152.1 MPa,能够承受较高的轴向载荷,提高植入物的力学稳态;D-2P-4G型梯度支架应力分布最为均匀,可有效减少应力集中,使得连接函数区域均能够有效传递应力,减少应力遮蔽;G-2D-4P型梯度支架流动速率变化最小,为0.10-0.48 mm/s,渗透率较高,有利于植入后体液在支架内部流动。基于三周期极小曲面的晶胞梯度支架设计为骨软骨支架设计提供了新思路,仿真分析结果也为支架植入人体后的骨整合预测提供了参考。

关键词：三周期极小曲面晶胞梯度连接函数骨软骨支架力学性能流体性能

超高效液相色谱-串联质谱法测定水体沉积物中17种新烟碱类杀虫剂及代谢物的残留量

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现代化工 2025年第1期45卷 261-265页

作者：徐彦杨继伟李剑徐巧俞晓峰姜佳钦杭州谱育科技发展有限公司浙江杭州310000 浙江工业大学化学工程学院浙江杭州310000

建立了基于全自动加速溶剂萃取-超高效液相色谱-串联质谱法检测水体沉积物中17种新烟碱类杀虫剂及代谢物残留的分析方法,17种目标物的质量浓度在一定范围内与对应的峰面积呈线性关系,该方法的检出限(3.143s)为0.0007~0.0022μg/kg。在0... 详细信息

建立了基于全自动加速溶剂萃取-超高效液相色谱-串联质谱法检测水体沉积物中17种新烟碱类杀虫剂及代谢物残留的分析方法,17种目标物的质量浓度在一定范围内与对应的峰面积呈线性关系,该方法的检出限(3.143s)为0.0007~0.0022μg/kg。在0.02、0.2、1.5μg/kg加标水平下的平均回收率为82.70%~114.30%,日内精密度和日间精密度的相对标准偏差分别为1.4%~9.4%和3.8%~9.7%。

关键词：全自动加速溶剂萃取新烟碱类杀虫剂超高效液相色谱-串联质谱法水体沉积物

Backward Doubly Stochastic Differential Equations with Stochastic Non-Lipschitz Coefficients

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Acta Mathematicae Applicatae Sinica 2024年第4期40卷 908-928页

作者： Si-yan xu Yi-dong ZHANG College of Science North China University of TechnologyBeijing 100144China

In this paper,we prove an existence and uniqueness theorem for backward doubly stochastic differential equations under a new kind of stochastic non-Lipschitz condition which involves stochastic and timedependent *** an application,we use the result to obtain the existence of stochastic viscosity solution for some nonlinear stochastic partial differential equations under stochastic non-Lipschitz conditions.

关键词： Stochastic non-Lipschitz coefficients backward doubly stochastic differential equation stochastic viscosity solutions

Applications of synthetic biology in medical and pharmaceutical fields

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Signal Transduction and Targeted Therapy 2023年第6期8卷 2638-2670页

作者： xu yan xu Liu Cuihuan Zhao Guo-Qiang Chen School of Life Sciences Tsinghua University100084BeijingChina PhaBuilder Biotech Co.Ltd. Shunyi DistrictZhaoquan Ying101309BeijingChina Center for Synthetic and Systems Biology Tsinghua University100084BeijingChina MOE Key Lab for Industrial Biocatalysis Dept Chemical EngineeringTsinghua University100084BeijingChina

Synthetic biology aims to design or assemble existing bioparts or bio-components for useful *** the past decades,progresses have been made to build delicate biocircuits,standardized biological building blocks and to develop various genomic/metabolic engineering tools and *** and pharmaceutical demands have also pushed the development of synthetic biology,including integration of heterologous pathways into designer cells to efficiently produce medical agents,enhanced yields of natural products in cell growth media to equal or higher than that of the extracts from plants or fungi,constructions of novel genetic circuits for tumor targeting,controllable releases of therapeutic agents in response to specific biomarkers to fight diseases such as diabetes and ***,new strategies are developed to treat complex immune diseases,infectious diseases and metabolic disorders that are hard to cure via traditional *** general,synthetic biology brings new capabilities to medical and pharmaceutical *** review summarizes the timeline of synthetic biology developments,the past and present of synthetic biology for microbial productions of pharmaceutics,engineered cells equipped with synthetic DNA circuits for diagnosis and therapies,live and auto-assemblied biomaterials for medical treatments,cell-free synthetic biology in medical and pharmaceutical fields,and DNA engineering approaches with potentials for biomedical applications.

关键词： diagnosis synthetic equipped

Hot deformation behavior and microstructure evolution of as-cast AZ91D magnesium alloy without pre-homogenization treatment

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Rare Metals 2013年第4期32卷 338-346页

作者： yan xu Lian-Xi Hu Yu Sun School of Materials Science and Engineering Harbin Institute of Technology School of Mechanical Engineering Beihua University

The deformation behavior and the microstruc-ture evolution of as-cast AZ91D magnesium alloy without pre-homogenization treatment were systematically inves-tigated. The flow stress behavior was studied by com-pression tests in strain rate range of 0.001-1.000 s^-1 and deformation temperature range of 220-380 ℃ with a maximum deformation strain of 60 %. The dependence of flow stress on deformation temperature and strain rate was described by hyperbolic sine constitutive equation. Through regression analysis, the average apparent activa- tion energy and coefficient of strain rate sensitivity were estimated to be 181.98 ***^-1 and 0.14, respectively. The results also reveal that the variation of peak stress depends on strain rate and deformation temperature. Microstructure observation shows that, at temperatures higher than 300 ℃ and strain rates lower than 0.01 s^-1, DRX developed extensively at the grain boundaries and in the core of coarse grains, resulting in a more homogeneous microstructure. Furthermore, the effects of strain, defor-mation temperature, strain rate, and eutectic β phase on the microstructure evolution of as-cast AZ91D magnesium alloy were discussed.

关键词： AZ91D magnesium alloy Isothermalcompression Constitutive equation Peak stress Microstructure evolution

Crystal-chemistry insight into the photocatalytic activity of BiOCI_(x)Br_(1_x)nanoplate solid solutions

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Frontiers of Materials Science 2017年第2期11卷 120-129页

作者： Huan-yan xu xu HAN Qu TAN Ke-Jia WU Shu-yan QI School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040China

In this study,a facile alcoholysis method was developed to synthesize BiOCI_(x)Br_(1_x)nanoplates at room temperature and atmospheric *** this route,strong acid or alkaline environment was absolutely avoided to realize the high exposure of{001}crystal *** regular changes in XRD peaks and cell parameters as a function of the Br content strongly declared that the obtained BiOCIxBrl_x products belonged to a group of solid *** 2D nanosheets with in-plane wrinkles were clearly observed in TEM ***,as the Br content increased,band gaps of BiOCI_(x)Br_(1_x)solid solutions gradually *** photocatalytic degradation of RhB under simulated sunlight irradiation indicated that ***0.5 had the best photocatalytic *** the viewpoint of crystal chemistry,the photocatalytic activity of BiOCI_(x)Br_(1_x)solid solutions was closely related with the exposure amount of{001}facets,interlayer spacing of(001)plane and energy-level position of valence band.

关键词： BiOCI_(x)Br_(1_x)solid solutions {001}facets exposure internal electric field interlayer spacing energy-level position