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Design of scale model of plate-shaped absorber in a wide frequency range

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Chinese Physics B 2018年第4期27卷 299-304页

作者： Li-Ming Yuan yong-gang xu Wei Gao Fei Dai Qi-Lin Wu Science and Technology on Electromagnetic Scattering Laboratory Shanghai 200438 China Key Laboratory of High Performance Fibers & Products Ministry of Education Donghua University Shanghai 201620 China

In order to design the scale model in a wide frequency range,a method based on the reflective loss is proposed according to the high-frequency approximation algorithm,and an example of designing the scale model of a plate-shaped absorber is given in this *** the example,the frequency of the full-size measurement ranges from 2.0 GHz to 2.4 GHz,the thickness of the full-size absorber is 1 mm and the scale ratio is 1/5.A two-layer scale absorber is obtained by the proposed *** thickness values of the bottom and top layer are 0.4 mm and 0.5 mm,***,the scattering properties of a plate model and an SLICY model are studied by FEKO to verify the effectiveness of the designed scale *** with the corresponding values from the theoretical scale model,the average values of the absolute deviations in 10 GHz～12 GHz are 0.53 d Bm^2,0.65 d Bm^2,0.76 d Bm^2 for the plate model and 0.20 d Bm^2,0.95 d Bm^2,0.77 d Bm^2 for the SLICY model while the incident angles are 0°,30°,and 60°,*** deviations fall within the Radar cross section（RCS） measurement ***,the work in this paper has important theoretical and practical significance.

关键词： scale model plate-shaped absorber wide frequency range RCS

A Dosimetric Comparison between Conventional Fractionated and Hypofractionated Image-guided Radiation Therapies for Localized Prostate Cancer

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Chinese Medical Journal 2016年第12期129卷 1447-1454页

作者： Ming Li Gao-Feng Li Xiu-Yu Hou Hong Gao yong-gang xu Ting Zhao Department of Radiation Oncology Beijing Hospital 8eijing 100730 China

Background： Image-guided radiation therapy （IGRT） is the preferred method for curative treatment of localized prostate cancer, which could improve disease outcome and reduce normal tissue toxicity reaction. 1GRT using cone-beam computed tomography （CBCT） in combination with volumetric-modulated arc therapy （VMAT） potentially allows smaller treatment margins and dose escalation to the prostate. The aim of this study was to compare the difference of dos^metric diffusion in conventional IGRT using 7-field, step-and-shoot intensity-modulated radiation therapy （IMRT） and hypofractionated IGRT using VMAT for patients with localized prostate cancer. Methods： We studied 24 patients who received 78 Gy in 39 daily fractions or 70 Gy in 28 daily fractions to their prostate with/without the seminal vesicles using IMRT （n = 12） or VMAT （n = 12） for prostate cancer between November 2013 and October 2015. Image guidance was performed using kilovoltage CBCT scans equipped on the linear accelerator. Offline planning was performed using the daily treatment images registered with simulation computed tomography （CT） images. A total of 212 IMRT plans in conventional cohort and 292 VMAT plans in hypofractionated cohort were enrolled in the study. Dose distributions were recalculated on CBCT images registered with the planning CT scanner. Results： Compared with 7-field, step-and-shoot IMRT, VMAT plans resulted in improved planning target volume （PTV） D95% （7663.17 ± 69.57 cGy vs. 7789.17± 131.76 cGy, P 〈 0.001）. VMAT reduced the rectal D25 （P 〈 0.001）, D35 （P 〈 0.001）, and D50 （P 〈 0.001）, bladder V50 （P 〈 0.001）, D25 （P = 0.002）, D35 （P = 0.028）, and D50 （P = 0.029）. However, VMAT did not statistically significantly reduce the rectal V50, compared with 7-field, step-and-shoot IMRT （25.02 ± 5.54% vs. 27.43 ±8.79%, P - 0.087）. Conclusions： To deliver the hypofractionated radiotherapy in prostate cancer, VMAT significantly increased PTV D95% dose and decreased the dose of radiation delivere

关键词： Hypofractionated Radiotherapy Image-guided Radiotherapy Prostate Cancer Treatment Planning Volumetric-modulatedArc Therapy

Influence of the Particle Size on the Rheology of Magnetorheological Elastomer

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Influence of the Particle Size on the Rheology of Magnetorhe...

2014中国功能材料科技与产业高层论坛

作者： QianJin yong-gang xu Yang Di Hao Fan School of Material Science and Engineering South west Jiaotong University

In this paper,the correlation between the particle size and rheological properties of MRE was discussed through both experimental results and theoretical *** shows that the particle size can significantly influence the magnetorheological effect by changing the initial shear modulus G and the saturated magnetic-induced shear modulus *** an increase in the particle size,the initial shear modulus G gets lower,and the saturated magnetic-induced shear modulus increases to the maximum and then *** larger the particle size is,the longerthe distance between neighbor particles along the magnetic field *** on the relationship between the particle size and shear modulus,there exists an optimum size for added ***,the performance of MRE can be improved by optimizing the particle size based on those rules.

关键词： Magnetorheological elastomer Particle size Initial shear modulus Saturated magnetic-induced shear modulus Magnetorheological effect

来源： cnki会议评论

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云南蒋家沟黏性泥石流输沙的涨落特征

泥沙研究 2017年第3期42卷 67-73页

作者：刘道川葛永刚谢云旭李泳中国科学院山地灾害与地表过程重点实验室四川成都610041 中国科学院-水利部成都山地灾害与环境研究所四川成都610041 中国科学院大学北京100049

间歇性阵流是山区小流域发生的黏性泥石流活动的基本形式,其输沙特性表现出一定的间歇性和涨落特性,其涨落可达均值的2~4个数量级。利用Hurst指数分析了蒋家沟近50年的数千阵泥石流观测资料,发现间歇性阵流的流量、径流量、输沙量序列的... 详细信息

间歇性阵流是山区小流域发生的黏性泥石流活动的基本形式,其输沙特性表现出一定的间歇性和涨落特性,其涨落可达均值的2~4个数量级。利用Hurst指数分析了蒋家沟近50年的数千阵泥石流观测资料,发现间歇性阵流的流量、径流量、输沙量序列的Hurst指数均大于0.5,说明序列具有一定程度的长程关联性。同时,对比阵流序列与洪峰序列,发现泥石流阵流的长程关联性强于洪峰序列。另一方面,输沙量的累积百分比均满足统一的指数分布形式:P(S)=CS^(-μ)exp(-S/S_c),其中μ越大意味着序列中输沙量较小的阵次越多;S_c表示的是阵流输沙的涨落情况,即S_c越大,阵流输沙的涨落越大。

关键词：泥石流阵流输沙 Hurst指数规模-频率分布涨落

Recent Advances in Fibrous Materials for Hydroelectricity Generation

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Nano-Micro Letters 2025年第2期17卷 109-133页

作者： Can Ge Duo xu Xiao Feng Xing Yang Zheheng Song Yuhang Song Jingyu Chen Yingcun Liu Chong Gao yong Du Zhe Sun Weilin xu Jian Fang College of Textile and Clothing Engineering Soochow UniversitySuzhou 215123People’s Republic of China National Engineering Laboratory for Modern Silk Soochow UniversitySuzhou 215123People’s Republic of China State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200People’s Republic of China Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123People’s Republic of China Department of Electrical and Computer Engineering University of MassachusettsAmherstMA 01003USA Department of Materials Imperial College LondonSouth Kensington CampusLondon SW72AZUK College of Textile Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China School of Materials Science and Engineering Shanghai Institute of Technology100 Haiquan RoadShanghai 201418People’s Republic of China

Depleting fossil energy sources and conventional polluting power generation pose a threat to sustainable *** generation from ubiquitous and spontaneous phase transitions between liquid and gaseous water has been considered a promising strategy for mitigating the energy *** materials with unique flexibility,processability,multifunctionality,and practicability have been widely applied for fibrous materials-based hydroelectricity generation(FHG).In this review,the power generation mechanisms,design principles,and electricity enhancement factors of FHG are first ***,the fabrication strategies and characteristics of varied constructions including 1D fiber,1D yarn,2D fabric,2D membrane,3D fibrous framework,and 3D fibrous gel are ***,the advanced functions of FHG during water harvesting,proton dissociation,ion separation,and charge accumulation processes are analyzed in ***,the potential applications including power supply,energy storage,electrical sensor,and information expression are also ***,some existing challenges are considered and prospects for future development are sincerely proposed.

关键词： Hydroelectricity Fibrous material Streaming potential Ion diffusion

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ACL移植隧道对半月板接触应力的影响仿真

系统仿真学报 2011年第11期23卷 2523-2528页

作者：黄荣瑛许勇刚胡磊徐强北京航空航天大学机械工程及自动化学院北京100191

基于CT和MRI数据建立含软骨与半月板的胫股关节三维模型的基础上,进行了三方面的研究:首先,对正常/含单束/双束移植隧道的胫股关节伸直位施加不同载荷进行有限元试验,分析关节伸直位时载荷对半月板内/外侧接触应力的影响;其二,应用并联... 详细信息

基于CT和MRI数据建立含软骨与半月板的胫股关节三维模型的基础上,进行了三方面的研究:首先,对正常/含单束/双束移植隧道的胫股关节伸直位施加不同载荷进行有限元试验,分析关节伸直位时载荷对半月板内/外侧接触应力的影响;其二,应用并联机构与ADAMS仿真,建立屈曲运动过程中的胫股关节模型;最后,在忽略单束/双束隧道对屈曲角胫股关节位姿影响的基础上,施加单一载荷对屈曲角(0°、30°、60°、90°)位姿时的胫股关节作有限元试验,分析ACL移植隧道对内/外侧半月板应力分布的影响。通过实验得到:内/外侧半月板的接触应力与载荷成线性关系,移植隧道在关节伸直位对内侧半月板的应力基本没有影响,在屈曲角90°时对其外侧的应力影响很小。然而,在屈曲角30°/60°的位姿时移植隧道使半月板内/外侧应力增加显著。因此,ACL重建后存在引起半月板慢性退变的可能性。

关键词：移植隧道胫股关节半月板位姿接触应力

Deciphering the role of ultra-low-loaded rhodium in NiFe-MIL-53 for superior oxygen evolution reaction

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Journal of Energy Chemistry 2025年第1期100卷 77-86页

作者： Jinzhi Jia Jinhua Zhang Kailu Guo Lanyue Zhang Gening Du Hao You Junfeng Huang Mudong Tu Hua Li yong Peng Wei Dou Cailing xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering School of Materials and Energy Lanzhou University College of Chemistry and Chemical Engineering Luoyang Normal University

Designing highly active and stable electrocatalysts of oxygen evolution reaction （OER） is one of the crucial *** this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium（Rh@NiFe-MIL-53）,is successfully prepared via the hydrothermal ***-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of NiFe-MIL-53 and the in-situ formed Rh@NiFeOOH is the actual active *** importantly,the enhanced reversibility of electrochemical reconstruction between NiFeOOH and NiFe（OH）2after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and Ni/Fe in Rh@***,theoretical calculations confirm that the integration of single-atom Rh into the NiFeOOH successfully reduces the band gap,regulates the d-band center （εd）,accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining ***,the optimized Rh@NiFe-MIL-53 exhibits excellent OER activity （240 mV） with a small Tafel slope of 48.2 mV dec-1and long-term durability (over1270 h at 10 m A cm-2and 110 h at 200 mA cm-2).This work presents a new perspective on designing highly efficient OER electrocatalysts.

关键词： X ray photoelectron spectroscopy

Enantio-divergent C–H borylation with two different ligands from a single chiral source

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Science China Chemistry 2025年第1期68卷 226-232页

作者： Rongrong Du Senmiao xu State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences College of Material Chemistry and Chemical Engineering Key Laboratory of Organosilicon Chemistry and Material TechnologyMinistry of Education Hangzhou Normal University University of Chinese Academy of Sciences

Reported here is an iridium-catalyzed enantio-divergent C（sp3）–H borylation of α-gem-dimethyl groups of trifluoromethyl ketone-derived hydrazones to construct a series of acyclic all-carbon quaternary stereocenters with a high level of chiral induction. Two different chiral bidentate boryl ligands from a common chiral source not only can switch the enantioselectivity but also are complementary in terms of the substrate scope.

关键词： asymmetric catalysis C–H borylation all-carbon quaternary stereocenters synthetic methods

Aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders:progress of experimental models based on disease pathogenesis

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Neural Regeneration Research 2025年第2期20卷 354-365页

作者： Li xu Huiming xu Changyong Tang Department of Neurology The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong ProvinceChina

Neuromyelitis optica spectrum disorders are neuroinflammatory demyelinating disorders that lead to permanent visual loss and motor *** date,no effective treatment exists as the exact causative mechanism remains ***,experimental models of neuromyelitis optica spectrum disorders are essential for exploring its pathogenesis and in screening for therapeutic *** most patients with neuromyelitis optica spectrum disorders are seropositive for IgG autoantibodies against aquaporin-4,which is highly expressed on the membrane of astrocyte endfeet,most current experimental models are based on aquaporin-4-IgG that initially targets *** experimental models have successfully simulated many pathological features of neuromyelitis optica spectrum disorders,such as aquaporin-4 loss,astrocytopathy,granulocyte and macrophage infiltration,complement activation,demyelination,and neuronal loss;however,they do not fully capture the pathological process of human neuromyelitis optica spectrum *** this review,we summarize the currently known pathogenic mechanisms and the development of associated experimental models in vitro,ex vivo,and in vivo for neuromyelitis optica spectrum disorders,suggest potential pathogenic mechanisms for further investigation,and provide guidance on experimental model *** addition,this review summarizes the latest information on pathologies and therapies for neuromyelitis optica spectrum disorders based on experimental models of aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorders,offering further therapeutic targets and a theoretical basis for clinical trials.

关键词： aquaporin-4 experimental model neuromyelitis optica spectrum disorder pathogenesis