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Research on Infrared Emissivity and Laser Reflectivity of Sn_(1−x)Er_(x)O_(2)Micro/Nanofibers Based on First-Principles

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Journal of Renewable Materials 2023年第2期11卷 921-936页

作者： Yuanjia Xia Fang Zhao Zhizun Li Zhaogang Cheng jianwei hu Shijiazhuang Campus Army Engineering University of PLAShijiazhuang050003China

Sn_(1−x)Er_(x)O_(2)(x=0%,8%,16%,24%)micro/nanofibers were prepared by electrospinning combined with heat treatment using erbium nitrate,stannous chloride and polyvinylpyrrolidone(PVP)as raw *** target products were characterized by thermogravimetric analyzer,X-ray diffrotometer,fourier transform infrared spectrometer,scanning electron microscope,spectrophotometer and infrared emissivity tester,and the effects of Er^(3+)doping on its infrared and laser emissivity were *** the same time,the Sn_(1−x)Er_(x)O_(2)(x=0%,16%)doping models were constructed based on the first principles of density functional theory,and the related optoelectronic properties such as their energy band structure,density of states,reflectivity and dielectric constant were analyzed,and further explained the mechanism of Er^(3+)doping on SnO_(2)infrared emissivity and laser absorption from the point of electronic *** results showed that after calcination at 600℃,single rutile type SnO_(2)was formed,and the crystal structure was not changed by doping Er^(3+).The calcined products showed good fiber morphology,and the average fiber diameter was 402 *** infrared emissivity and resistivity of the samples both decreased first and then increased with the increase of Er^(3+)doping *** x=16%,the infrared emis-sivity of the sample was at least 0.71;and Er^(3+)doping can effectively reduce the reflectivity of SnO_(2)at 1.06μm and 1.55μm,when x=16%,its reflectivity at 1.06μm and 1.55μm are 50.5%and 40%,respectively,when x=24%,the reflectivity at 1.06μm and 1.55μm wavelengths are 47.3%and 42.1%,*** the same time,the change of carrier concentration and electron transition before and after Er^(3+)doping were described by first-principle calculation,and the regulation mechanism of infrared emissivity and laser reflectivity was *** study provides a certain experimental and theoretical basis for the development of a single-type,light-weight and easily prepa

关键词： Micro/nano fibers Er^(3+)doping SnO_(2) laser and infrared compatible stealth material

Protective effects of baicalin on amyloid beta 25-35-induced apoptosis in human neuroblastoma SH-SY5Y cells

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Neural Regeneration Research 2010年第22期5卷 1739-1744页

作者： Miao Geng Hongyan Chen Jianhua Wang Yazhuo hu jianwei Liu Jing Liu Jingkun Pan Yuhong Gao Institute of Geriatrics Division of South Building Chinese PLA General Hospital Beijing 100853 China

Baicalin, a type of flavanoid, effectively prevents cellular apoptosis induced by various factors. However, little evidence is available regarding its role on amyloid β （Aβ） -induced neuronal apoptosis. The present study investigated the protective mechanisms of baicalin on Aβ-induced neuronal apoptosis. Flow cytometry and cation dye 5, 5＇, 6, 6＇-tetrachloro-1, 1＇, 3, 3＇-tetraethyl- benzimidazoly lcarbocyanine iodide （JC-1） were employed to measure mitochondrial membrane potential, and nitric oxide secretion and apoptotic-related factors, such as caspase-3, were comprehensively analyzed. Results demonstrated a protective effect of baicalin on Aβ-treated SH-SY5Y cell viability; the rate of apoptosis decreased, nitric oxide generation and expression of caspase-3 were effectively inhibited, and mitochondrial membrane potential was effectively protected. Baicalin inhibited Aβ-induced neuronal apoptosis via multiple targets and multiple pathways, such as the inhibition of free radical damage, reduction of caspase-3 expression, and protection of normal mitochondrial functions.

关键词： baicalin neuron apoptosis traditional Chinese medicine caspase-3 amyloid β neural regeneration

Impact of 5-Fu/oxaliplatin on mouse dendritic cells and synergetic effect with a colon cancer vaccine

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Chinese Journal of Cancer Research 2018年第2期30卷 197-208页

作者： Xinqiang Hong Tiangeng Dong Tuo Yi jianwei hu Zhen Zhang Shengli Lin Weixin Niu Department of General Surgery Zhongshan Hospital Fudan University

Objective： The aim of the present study was to investigate the effects of 5-fluorouracil（5-Fu） and oxaliplatin on the function and activation pathways of mouse dendritic cells（DCs）, and to clarify whether 5-Fu/oxaliplatin combined with the CD1d-MC38/α-galactosylceramide（α-GC） tumor vaccine exhibits synergistic effects on the treatment of colon cancer in ***： The combination of the Toll like receptor（TLR） ligands and/or 5-Fu/oxaliplatin was added into myeloid-derived DCs in vitro culture. DC phenotypic changes were detected by flow cytometry, and the secretion of DC cytokines was detected by cytometric bead array（CBA）. A MC38 mouse colon cancer model was constructed and the DCs were isolated from the spleen, tumor tissue and lymph nodes following intraperitoneal injection of 5-Fu/oxaliplatin. The cell phenotypes were detected by flow cytometry. The tumor infiltrating leukocytes,splenocytes and lymph node cells were co-cultured with the dead MC38 tumor cells, and the secretion levels of interferon-γ（IFN-γ） were detected. 5-Fu/oxaliplatin combined with our previously developed CD1d-MC38/α-GC tumor vaccine was used to inhibit the growth of MC38 colon cancer in mice, and the tumor growth rate and survival time were ***： 5-Fu/oxaliplatin exerted no significant effect on the expression of the stimulating phenotypes of DCs in vitro, while it could reduce the expression of programmed death ligand 1/2（PD-L1/L2） and promote interleukin-12（IL-12） secretion by DCs. Furthermore 5-Fu/oxaliplatin was beneficial to the differentiation of T-helper 1（Th1） cells. 5-Fu/oxaliplatin further enhanced the stimulating phenotypic expression of DCs in tumor bearing mice, decreased PD-L1/L2 expression, and specifically activated the lymphocytes. The CD1d-MC38/α-GC tumor vaccine combined with 5-Fu/oxaliplatin could exert a synergistic role that resulted in a significant delay of the tumor growth rate, and an increase in the survival time of tumor bearing ***： 5

关键词： Dendritic cell colon cancer cancer vaccine chemoimmunotherapy

Osteogenesis effects of magnetic nanoparticles modified-porous scaffolds for the reconstruction of bone defect after bone tumor resection

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Regenerative Biomaterials 2019年第6期6卷 373-381页

作者： Ming Li Jianheng Liu Xiang Cui Guofei Sun jianwei hu Sijia Xu Fei Yang Licheng Zhang XiumeiWang Peifu Tang Department of Orthopaedics Chinese PLA General HospitalBeijing 100853China Beijing National Laboratory for Molecular Sciences State Key Laboratory of Polymer Physics and ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing 100190China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

The treatment of bone defect after bone tumor resection is a great challenge for orthopedic *** should consider that not only to inhibit tumor growth and recurrence,but also to repair the defect and preserve the limb ***,it is necessary to find an ideal functional biomaterial that can repair bone defects and inactivate *** nanoparticles(MNPs)have its unique advantages to achieve targeted hyperthermia to avoid damage to surrounding normal tissues and promote osteoblastic activity and bone *** on the previous stage,we successfully prepared hydroxyapatite(HAP)composite poly(lactic-co-glycolic acid)(PLGA)scaffolds and verified its good osteogenic properties,in this study,we produced an HAP composite PLGA scaffolds modified with *** composite scaffold showed appropriate porosity and mechanical characteristics,while MNPs possessed excellent magnetic and thermal *** cytological assay indicated that the MNPs have antitumor ability and the composite scaffold possessed good *** vivo bone defect repair experiment revealed that the composite scaffold had good osteogenic ***,we could demonstrate that the composite scaffolds have a good effect in bone repair,which could provide a potential approach for repairing bone defect after bone tumor excision.

关键词： bone tumor magnetic nanomaterials PLGA scaffold bone repair

WAVELET ANALYSIS OF MODULATED SIGNALS

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Journal of Electronics(China) 2006年第4期23卷 490-494页

作者： hu jianwei Yang Shaoquan School of Electronic Engineering Xidian Univ Xi＇an 710071 China

The relationship between Haar wavelet decomposition coefficients and modulated signal parame-ters is discussed. A new modulation classification method is presented. The new method uses the amplitude, frequency and phase information derived from Haar wavelet decomposition as feature vectors to distinguish the modulation types of M-ary Frequency-Shift Keying (MFSK), M-ary Phase-Shift Keying (MPSK) and Quadrature Amplitude Modulation (QAM) modulation types. A parallel combined classifier is designed based on these feature vectors. The overall successful recognition rate of 92.4% can be achieved even at a low Sig-nal-to-Noise Ratio (SNR) of 5dB.

关键词： Haar wavelet decomposition Modulated signal Modulation recognition

计算圆柱绕流拉力系数的自适应迎风有限元方法(英文)

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计算物理 2009年第3期26卷 378-388页

作者：马岩胡健伟南开大学数学科学学院天津300071

研究圆柱绕流中拉力系数的自适应计算问题.对二维定常粘性不可压Navier-Stokes方程使用迎风有限元格式,通过引入对偶问题,得到圆柱拉力系数的加权后验误差估计器,实现了自适应网格加密.数值实验表明格式的可行性以及估计器的稳健性.

关键词： Navier-Stokes方程圆柱绕流拉力系数自适应迎风有限元后验误差估计

Ⅰ-Ⅴ型夹芯板在近爆冲击波和破片群联合作用下防爆性能研究

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湖南大学学报（自然科学版） 2019年第1期46卷 32-46页

作者：田力胡建伟天津大学建筑工程学院天津300072 天津大学滨海土木工程结构与安全教育部重点实验室天津300072

针对民用建筑物墙、板构件提出一种新型的Ⅰ-Ⅴ型夹芯板防护结构,采用非线性有限元软件LS-DYNA,开展近爆冲击波和破片群联合作用下Ⅰ-Ⅴ型夹芯板的防护性能研究.从质量损失、能量吸收和竖向峰值位移响应3个方面,研究了炸药比例距离、炸... 详细信息

针对民用建筑物墙、板构件提出一种新型的Ⅰ-Ⅴ型夹芯板防护结构,采用非线性有限元软件LS-DYNA,开展近爆冲击波和破片群联合作用下Ⅰ-Ⅴ型夹芯板的防护性能研究.从质量损失、能量吸收和竖向峰值位移响应3个方面,研究了炸药比例距离、炸药起爆位置对夹芯板防护效果的影响,同时对夹芯板的实际防护性能进行了验证.结果表明:炸药比例距离对Ⅰ-Ⅴ型夹芯板的防护性能有较大的影响;不同炸药起爆位置对Ⅰ-Ⅴ型夹芯板的毁伤程度不同,在轴向增加起爆点的个数并不能显著增大Ⅰ-Ⅴ型夹芯板的毁伤程度;有Ⅰ-Ⅴ型夹芯板防护的钢筋混凝土板迎爆面只有少量混凝土脱落,且无钢筋外露,背爆面无混凝土脱落,也无钢筋外露,塑性变形区域较小,整体没有形成贯穿破坏,Ⅰ-Ⅴ型夹芯板的实际防护效果很好.

关键词：冲击波破片群联合作用夹芯板结构防护设计

近爆冲击波和破片群联合作用下I-V型夹芯板的防护性能研究

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中南大学学报（自然科学版） 2018年第11期49卷 2831-2842页

作者：田力胡建伟天津大学建筑工程学院天津300072 天津大学滨海土木工程结构与安全教育部重点实验室天津300072

为了研究民用建筑物墙、板构件在近爆冲击波及破片联合作用下的防护性能,提出1种新型I-V型夹芯板防护结构;利用非线性有限元分析软件LS-DYNA,分析冲击波、破片群单独作用及二者联合作用下I-V型夹芯板的毁伤效果的差异;在保持用钢质量不... 详细信息

为了研究民用建筑物墙、板构件在近爆冲击波及破片联合作用下的防护性能,提出1种新型I-V型夹芯板防护结构;利用非线性有限元分析软件LS-DYNA,分析冲击波、破片群单独作用及二者联合作用下I-V型夹芯板的毁伤效果的差异;在保持用钢质量不变的前提下,从夹芯板质量损失、能量吸收和竖向峰值位移3个方面,研究夹芯板的上、下面板厚度及夹芯层配置对其防护性能的影响,并与其他类型的夹芯板进行对比。研究结果表明:冲击波和破片群联合作用下对夹芯板的破坏效果具有叠加累积效应,明显强于两者单一作用下破坏效果的线性叠加;在相同荷载工况下,I-V型夹芯板防护效果最优;上、下面板厚度及夹芯层配置对I-V型夹芯板的防护性能有较大的影响;不同侵彻位置下I-V型夹芯板的防护性能基本相同,无局部薄弱部位,整体防护性能较好;不同破片作用下I-V型夹芯板的防护性能不同,破片截面边长为15 mm时夹芯板防护性能最好。

关键词：冲击波破片群联合作用夹芯板结构防护设计

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多幅竖向拼接预制预应力地连墙围护分析研究

地下空间与工程学报 2018年第3期14卷 786-791页

作者：胡坚尉上海市政工程设计研究总院(集团)有限公司上海200092

预制预应力地连墙是一种新型的结构形式,且符合预制装配式的发展方向,其研究具有重大的意义。但单幅预制预应力地连墙长度过长,施工很不方便且成本巨大。将预制预应力地连墙分为竖向多幅,选取上海地区典型地质,对多幅竖向拼接的预制预... 详细信息

预制预应力地连墙是一种新型的结构形式,且符合预制装配式的发展方向,其研究具有重大的意义。但单幅预制预应力地连墙长度过长,施工很不方便且成本巨大。将预制预应力地连墙分为竖向多幅,选取上海地区典型地质,对多幅竖向拼接的预制预应力地连墙在多变量下进行有限元模拟分析,在围护墙体自身变形、受力及周边环境保护等方面进行了系统的比较分析。结果表明,在多幅地连墙的合适部位施加预应力,能有效地减小围护墙体变形,且施加预应力越大,控制效果越明显,同时,地连墙上空心率对地连墙变形影响不大。研究结果有利于将来预制预应力地连墙的推广运用。

关键词：地下连续墙预应力预制多幅竖向拼接变形