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Rare Metals 2022年第10期41卷 3421-3431页

作者： Guan-Li Xu Yu-Dong Gong Chang Miao qing Wang shu-qing nie Yu Xin Min-Yue Wen Jian Liu Wei Xiao College of Chemistry and Environmental Engineering Yangtze UniversityJingzhou434023China Hebei Key Laboratory of Dielectric and Electrolyte Functional Material Northeastern University at QinhuangdaoQinhuangdao066004China Peking University Science Park Beijing100871China School of Engineering Faculty of Applied ScienceThe University of British ColumbiaKelownaBCV1V 1V7Canada

The composite powders,Sn nanoparticles embedded into the porous hydrogel-derived carbon(Sn@PHDC),were successfully prepared by polymerization and calcination processes,and the characterization results confirmed that Sn nanoparticles were homogeneously dispersed in the porous hydrogel-derived pyrolytic *** coin cell assembled with the Sn@PHDC-50 composite electrode presented good cyclic stability and rate performance when the weight ratio of Sn nanoparticles to hydrogel-derived pyrolytic carbon was maintained at 1:***,the Sn@PHDC-50 electrode manifested a lower charge transfer resistance of 58.57 Ω and a higher lithium ions diffusion coefficient of 1.117×10^(-14) cm^(2)·s^(-1) than pure Sn and other Sn@PHDC *** improvements can be partly ascribed to the fact that the hydrogelderived pyrolytic c arbon matrix can release the volume strain and enhance the electronic conductivity of the composite electrode,and partly to the fact that the porous hydrogelderived pyrolytic carbon matrix can suppress agglomerations of Sn nanoparticles and shorten Li^(+) diffusion *** work may provide a new appro ach for the improvement of Sn-based anode materials for lithium-ion batteries.

关键词： Sn nanoparticles Hydrogel Composite anode Electrochemical performance Lithium-ion battery

Dual modification of LiNi_(0.83)Co_(0.11)Mn_(0.06)O_(2) cathode materials by K^(+) doping and Li_(3)PO_(4) coating for lithium ions batteries

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Rare Metals 2024年第7期43卷 3007-3018页

作者： Wei Xiao Jia-Le Wang Zhi-Cheng Yi Cheng-Jin Liu Chang Miao Yu Xin shu-qing nie College of Chemistry and Environmental Engineering Yangtze UniversityJingzhou 434023China

Li_(3)PO_(4)@Li_(0.99)K_(0.01)Ni_(0.83)Co_(0.11)Mn_(O.06)O_(2)(NCM-KP) cathode powders are synthesized via K^(+)doping in calcination processes and H_3PO_4 coating in sol-gel processes.K^(+) precisely enters into the lattice to widen the(003) plane to 0.4746 nm with a lower cationic disordered degree of 1.87%.Moreover,the surface residual lithium salts are treated by H_3PO_4 to generate a uniform Li_(3)PO_(4) coating layer of approximately 11.41 nm,which completely covers on the surface of secondary spherical particles to improve the interfacial *** 25℃,the NCM-KP electrode delivers a discharge specific capacity of 148.9 mAh·g^(-1) with a remarkable capacity retention ratio of 84.1% after 200 cycles at 1.0C and retains a high reversible specific capacity of 154.4 mAh·g^(-1) at *** at 1.0C and 60℃,it can maintain a reversible discharge specific capacity of 114.6 mAh·g^(-1) with 0.21% of capacity decay per cycle after 200 cycles,which is significantly lower than 0.40% for the pristine NCM ***,the charge transfer resistance of 238.89 Ω for the NCM-KP electrode is significantly lower than 947.41 Ω for the pristine NCM one by restricting the interfacial side ***,combining K+doping and Li_(3)PO_(4) coating is an effective strategy to enable the significant improvement of the electrochemical property of high-nickel cathode materials,which may be mainly attributed to the widened diffusion pathway and the formed Li_(3)PO_(4) protective layer,thus promoting Li~+diffusion rate and preventing the erosion of HF.

关键词： High-nickel cathode material Residual lithium K^(+)doping Li_(3)PO_(4)coating Lithium ions battery

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干细胞的趋电性迁移及机制

中国组织工程研究 2025年第23期29卷 4984-4992页

作者：韩芳舒晴贾绍辉田峻武汉体育学院运动医学院湖北省武汉市430079 武汉大学中南医院骨科康复科湖北省武汉市430071

背景:随着对干细胞技术研究的深入,如何使其准确归巢成为临床应用中的一大难题。除药物和趋化因子等信号的诱导外,电场也被广泛应用于指导干细胞的定向迁移,并可增强其迁移速度和定向性。目的:旨在分析总结电场对干细胞迁移特性的影响,... 详细信息

背景:随着对干细胞技术研究的深入,如何使其准确归巢成为临床应用中的一大难题。除药物和趋化因子等信号的诱导外,电场也被广泛应用于指导干细胞的定向迁移,并可增强其迁移速度和定向性。目的:旨在分析总结电场对干细胞迁移特性的影响,同时综述可能的作用机制。方法:通过检索Pub Med和中国知网数据库,收集截至2024年3月的相关文献,英文检索词:“stem cells,direct current electric field,pulsed electric field,migration,electric field device,mechanism”;中文检索词:“干细胞,直流电场,脉冲电场,迁移,电场装置,机制”。排除不能获取全文和与主题无关的文献。结果与结论:根据筛选要求共纳入58篇文献,包括中文文献15篇及英文文献43篇。文献以脂肪间充质干细胞、骨髓间充质干细胞、神经干细胞、表皮干细胞、人胚胎干细胞和人诱导性多功能干细胞为研究对象,在迁移装置中研究电场的不同参数对上述干细胞迁移的影响及其机制。(1)电场作为一种简单、无创且稳定的干预方式在指导干细胞定向迁移的过程中起着积极作用;(2)不同类型的干细胞发生趋电性迁移的方向不同,同时大部分干细胞的迁移速度和定向性是随着电场强度增加而增加的;(3)不同的电场装置在观测干细胞迁移时的侧重点不同,可根据实验目的而择优选择相关装置;(4)不同干细胞趋电性迁移的机制不完全相同,多数干细胞迁移过程中有MAPK通路、ROCK活化以及PI3K功能的参与,同时还有其他蛋白质复合物与信号通路参与调控该过程;(5)除电场参数不同之外,细胞本身的衰老情况和培养环境也会对趋电性迁移的结果产生影响。总而言之,电场作为一种影响干细胞迁移特性的重要信号,与其他新兴材料结合在组织工程应用中展现出了一定的潜力,有望在指导干细胞归巢方面发挥更加重要的作用,促进骨组织再生和修复以及神经系统、自身免疫系统以及肿瘤等疾病的研究取得更大的突破。

关键词：干细胞电场趋电性迁移机制归巢效应物理因子电场装置细胞衰老培养环境

SPATIALLY-LOCALIZED SCAFFOLD PROTEINS MAY FACILITATE TO TRANSMIT LONG-RANGE SIGNALS

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Acta Mathematica Scientia 2009年第6期29卷 1657-1669页

作者： Xinfeng Liu qing nie Department of Mathematics University of South Carolina Columbia SC 29208 USA Department of Mathematics Center for Mathematical and Computational Biology University of California Irvine CA 92697 USA

Scaffold proteins play an important role in the promotion of signal transmission and specificity during cell signaling. In cells, signaling proteins that make up a pathway are often physically orgnaized into complexes by scaffold proteins [1]. Previous work [2] has shown that spatial localization of scaffold can enhance signaling locally while simultaneously suppressing signaling at a distance, and the membrane confinement of scaffold proteins may result in a precipitous spatial gradient of the active product protein, high close to the membrane and low within the cell. However, cell-fate decisions critically depend on the temporal pattern of product protein close to the nucleus. In this paper, when phosphorylation signals cannot be transfered by diffusion only, two mechanisms have been proposed for long-range signaling within cells： multiple locations of scaffold proteins and dynamical movement of scaffold proteins. Thus, here we have unveiled how the spatial propagation of the phosphorylated product protein within a cell depends on the spatially and temporal localized scaffold proteins. A class of novel and fast numerical methods for solving stiff reaction diffusion equations with complex domains is briefly introduced.

关键词： scaffold proteins signal pathway reaction-diffusion equations

Influence of Isotope Effects on Product Polarizations of N(~2D)+D_2, N(~2D)+H_2 and N(~2D)+HD Reactive Systems

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Chemical Research in Chinese Universities 2012年第5期28卷 897-902页

作者： nie Shan-shan CHU Tian-shu State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023P.R.China Institute for Computational Sciences and Engineering Laboratory of New Fiber Materials and Modern Textilethe Growing Base for State Key LaboratoryQingdao UniversityQingdao 266071P.R.China

To figure out the influence of isotope effect on product polarizations of the N（2D）＋D2 reactive system and its isotope variants, quasi-classical trajectory（QCT） calculation was performed on Ho＇s potential energy surface（PES） of 2A″ state. Product polarizations such as product distributions of P（θr）, P（φr） and P（θr,φr）, as well as the generalized polarization-dependent differential cross sections（PDDCSs） were discussed and compared in detail among the four product channels of the title reactions. Both the intermolecular and intramolecular isotope effects were proved to be influential on product polarizations.

关键词： Isotope effect Product polarization Quasi-classical trajectory calculation Potential energy surface

Regulation of morphology and visible light-driven photocatalysis of WO_(3)nanostructures by changing pH

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Rare Metals 2021年第7期40卷 1738-1745页

作者： You-shu Fan Xiao-Li Xi Yang-Si Liu Zuo-Ren nie Lin-Yan Zhao qing-Hua Zhang College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaBeijing University of TechnologyBeijing 100124China National Engineering Laboratory for Industrial Big-data Application Technology Beijing University of TechnologyBeijing 100124China

The controlled preparation of hexagonal tungsten trioxide(h-WO_(3))nanostructures was achieved by adjusting the pH of the precursor *** effect of the pH on the morphology,elemental composition,and photocatalytic performance of the samples was characterized via X-ray diffraction(XRD),scanning electron microscopy,energy dispersive X-ray spectroscopy,and Raman ***-visible(UV-Vis)spectra were used to evaluate the absorbance and the photocatalytic performance of methylene ***(PL),electrochemical impedance spectroscopy,photocurrent response and Brunauer-Emmett-Teller(BET)were used to study the optical properties,electrical performance,and specific surface area of the WO_(3)-nanostructures,*** results indicate that the WO_(3) nanorods prepared at pH=1.0 exhibit the highest photocatalytic performance(87.4%in 1 h),whereas the WO_(3) nanoblocks prepared at p H=3.0 show the *** photocatalytic performance of the one dimensional(1 D)-nanorods can be attributed to their high specific surface area and charge transfer *** h-WO_(3) nanostructures were synthesized via a simple method and without a capping *** show an excellent photocatalytic performance,which is promising for their application in environment purification.

关键词： h-WO_(3) Morphology pH Photocatalysis Charge transfer Optoelectrical properties

ULF electromagnetic precursors before the 1999 Jiji, Taiwan, earthquake and the comparison with results of simulating experiments

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Acta Seismologica Sinica(English Edition) 2001年第3期14卷 342-348页

作者： QIAN shu-qing 1. Laboratory of Tectonophysics & Institute of Geophysics China Seismological Bureau 100081 Beijing China 2. Seismological Bureau of Fujian Province 350003 Fuzhou China

There are many reports about the abnormal electromagnetic signals observed before great earthquakes. In particular, the signals of electromagnetic anomalies before the Hyogo-Ken Nanbu, Japan, MS=7.2 earthquake on January 17, 1995 (Hayakawa, et al, 1996) and those before the Loma Prieta, USA, MS=7.1 earthquake on October 19, 1989 (Fraser-Smith, et al, 1990) are especially remarkable. However, what the above authors reported are only the phenomena of one or two observatories. In order to confirm this phenomenon, the authors studied the results obtained by nine observatories in the southeast coastal areas of Chinese mainland within a range of 256~858 km to the epicenter of the 1999 Jiji, Taiwan, earthquake using instruments of the same type (the ULF/VLF electromag-netic wave observation system). By summarizing the data for the three months up to the time of earthquake occur-rence, the authors obtained the regional distribution of the signals of electromagnetic anomalies before the earth-quake and their features in the time domain and frequency domain.

关键词： Jiji earthquake experiment of rock fracture under compression ULF electromagnetic precursors mechanism of production and propagation P319

Surface Diffusion on Stressed Solid Surface

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Communications in Computational Physics 2007年第1期2卷 73-86页

作者： Xiaofan Li qing nie Department of Applied Mathematics Illinois Institute of TechnologyChicagoIL 60616USA Center for Mathematical and Computational Biology Department of MathematicsUniversity of CaliforniaIrvineCA 92697-3875USA

The surface diffusion of an axi-symmetric solid,a whisker,subject to applied uniaxial stress,is studied numerically based on a new boundary integral formulation for periodic stress *** efficient semi-implicit time-stepping scheme is developed to treat the serve stiffness due to high-order *** the initial perturbation is small the effect of the stress on the motion of the whisker is found to agree with the linear stability *** simulations of a fully nonlinear case are also presented,and a potential break-up of the whisker is observed.

关键词： Surface diffusion elastic stress boundary integral method semi-implicit scheme.

Simulation and Instability Investigation of the Flow around a Cylinder between Two Parallel Walls

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Journal of Thermal Science 2015年第2期24卷 140-148页

作者： DOU Hua-shu BEN An-qing Faculty of Mechanical Engineering and Automation Zhejiang Sci-Tech University

The two-dimensional flows around a cylinder between two parallel walls at Re=40 and Re=100 are simulated with computational fluid dynamics(CFD). The governing equations are Navier-Stokes equations. They are discretized with finite volume method(FVM) and the solution is iterated with PISO Algorithm. Then, the calculating results are compared with the numerical results in literature, and good agreements are obtained. After that, the mechanism of the formation of Karman vortex street is investigated and the instability of the entire flow field is analyzed with the energy gradient theory. It is found that the two eddies attached at the rear of the cylinder have no effect on the flow instability for steady flow, i.e., they don't contribute to the formation of Karman vortex street. The formation of Karman vortex street originates from the combinations of the interaction of two shear layers at two lateral sides of the cylinder and the absolute instability in the cylinder wake. For the flow with Karman vortex street, the initial instability occurs at the region in a vortex downstream of the wake and the center of a vortex firstly loses its stability in a vortex. For pressure driven flow, it is confirmed that the inflection point on the time-averaged velocity profile leads to the instability. It is concluded that the energy gradient theory is potentially applicable to study the flow stability and to reveal the mechanism of turbulent transition.

关键词： numerical simulation cylinder energy gradient theory stability inflection point

Synthesis of nitrogen-doped reduced graphene oxide/magnesium ferrite/polyaniline composite aerogel as a lightweight,broadband and efficient microwave absorber

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Journal of Materials Science & Technology 2024年第8期175卷 115-124页

作者： Ruiwen shu Lijuan nie Ziwei Zhao Xunhong Yang School of Chemical Engineering State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal MinesAnhui University of Science and TechnologyHuainan 232001China Joint National-Local Engineering Research Centre for Safe and Precise Coal Mining Anhui University of Science and TechnologyHuainan 232001China

The fabrication of graphene-based microwave absorbing materials with low density,small filling ratio,broad bandwidth and strong absorption remains a huge *** this work,nitrogen-doped reduced graphene oxide/magnesium ferrite/polyaniline(NRGO/MgFe_(2)O_(4)/PANI)composite aerogel was synthesized by a three-step method of solvothermal reaction,in situ chemical oxidation polymerization and hydrothermal *** results showed that the obtained aerogels had a unique three-dimensional(3D)porous network structure and low bulk density(11.1-13.0 mg cm^(−3)).It was worth noting that in the NRGO/MgFe_(2)O_(4)/PANI ternary composite aerogel,MgFe_(2)O_(4)coated with a thin PANI layer was anchored on the surface of NRGO ***,the NRGO/MgFe_(2)O_(4)/PANI ternary composite aerogel showed much better microwave absorbing capacity compared with pure NRGO aerogel and NRGO/MgFe_(2)O_(4)binary composite *** the filling ratio was as low as 11.5 wt.%,the obtained ternary composite aerogel exhibited the maximum effective absorption bandwidth of 7.0 GHz at a matching thickness of 2.1 mm,and the minimum reflection loss of-42.9 dB at a thickness of 3.57 ***,the prob-able microwave dissipation mechanism was also *** was believed that this study would pave the way for the construction of 3D graphene-based composites as lightweight,broadband and efficient microwave absorbents.

关键词： Graphene Composite aerogel Polyaniline Magnesium ferrite Microwave absorption