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Stress, Roughness and Reflectivity Properties of Sputter-Deposited B4C Coatings for X-Ray Mirrors

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Chinese Physics Letters 2019年第12期36卷 17-21页

作者： Jia-Li Wu Run-Ze Qi Qiu-Shi huang Yu-Fei feng Zhan-Shan Wang Zi-Hua Xin Department of Physics Shanghai UniversityShanghai 200444 MOE Key Laboratory of Advanced Micro-Structured Materials Shanghai 200092 Institute of Precision Optical Engineering School of Physics Science and EngineeringTongji UniversityShanghai 200092

Boron carbide(B4C)coatings have high reflectivity and are widely used as mirrors for free-electron lasers in the x-ray ***,B4C coatings fabricated by direct-current magnetron sputtering show a strong compressive stress of about-3 *** changing the argon gas pressure and nitrogen-argon gas mixing ratio,we are able to reduce the intrinsic stress to less than-1 GPa for a 50-nm-thick B4C *** is found that the stress in a coating deposited at 10 m Torr is-0.69 GPa,the rms roughness of the coating surface is 0.53 nm,and the coating reflectivity is 88%,which is lower than those of coatings produced at lower working *** the working gas contains 8%nitrogen and 92%argon,the B4 C coating shows not only-1.19 GPa stress but also a low rms roughness of 0.16 nm,and the measured reflectivity is 93%at the wavelength of 0.154 nm.

关键词： coating stress carbide

Human umbilical cord blood stem cells and brainderived neurotrophic factor for optic nerve injury: a biomechanical evaluation

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Neural Regeneration Research 2015年第7期10卷 1134-1138页

作者： Zhong-jun Zhang Ya-jun Li Xiao-guang Liu feng-xiao huang Tie-jun Liu Dong-mei Jiang Xue-man Lv Min Luo Department of Mechanics PLA Air Force Aviation University Mathematics School Jilin University Department of Ophthalmology China-Japan Friendship Hospital Jilin University Department of Pain China-Japan Friendship Hospital Jilin University

Treatment for optic nerve injury by brain-derived neurotrophic factor or the transplantation of human umbilical cord blood stem cells has gained progress, but analysis by biomechanical indicators is rare. Rabbit models of optic nerve injury were established by a clamp. At 7 days after injury, the vitreous body received a one-time injection of 50 μg brain-derived neurotrophic factor or 1 × 10^6 human umbilical cord blood stem cells. After 30 days, the maximum load, maximum stress, maximum strain, elastic limit load, elastic limit stress, and elastic limit strain had clearly improved in rabbit models of optical nerve injury after treatment with brain-derived neurotrophic factor or human umbilical cord blood stem cells. The damage to the ultrastructure of the optic nerve had also been reduced. These findings suggest that human umbilical cord blood stem cells and brain-derived neurotrophic factor effectively repair the injured optical nerve, improve biomechanical properties, and contribute to the recovery after injury.

关键词： nerve regeneration optic nerve injury human umbilical cord blood stem cells brain-derived neurotrophic factor biomechanical properties neural regeneration

A Review of Mg Isotope Analytical Methods by MC-ICP-MS

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Journal of Earth Science 2014年第5期25卷 822-840页

作者： Yajun An Fang huang CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China

Application of multi-collector inductively coupled plasma mass spectrometry（MC-ICP-MS） has led to big breakthrough of analytical methods for metal stable isotopes, resulting in rapid progresses in non-traditional stable isotope geochemistry. As a new geological tracer, Mg isotopes have been widely applied in studies of almost all important disciplines of geochemistry. High precision Mg isotope data measured by MC-ICP-MS are now available with precision about 0.05‰ amu-1（2SD） or better. Because mass bias caused by chemical procedure and instrument can easily cause significant analytical error, it is still a challenge to obtain accurate Mg isotope data for natural samples. In this paper, we systematically review the development of analytical technique of Mg isotopes, with a detailed description of a series of important techniques used in the measurement process, including calibration of instrumental mass-bias, chemical purification process, matrix effect, and pitfalls for high precision isotope analyses. We compare standard data from different labs and establish a guideline for Mg isotope analysis procedure. Additionally, we briefly discuss the behaviors of Mg isotopes during geological processes including equilibrium and kinetic Mg isotope fractionations, such as magma differentiation, chemical and thermal diffusion, and continental weathering. Finally, we propose some future prospects for Mg isotope geochemistry in both high and low temperature geological processes.

关键词： magnesium isotope MC-ICP-MS isotope fractionation.

Hexagonal and Orthorhombic Perovskite Phases of ErMnO_3 and TmMnO_3 from Hydrothermal Systems

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Chemical Research in Chinese Universities 2010年第5期26卷 707-711页

作者： ZHU Lin-lin CHEN Yan huang Ke-ke ZHANG Gang-hua HU Wei-wei YUAN Hong-ming CHANG Hai-bo feng Shou-hua State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University Changchun 130012 P. R. China Resource and Environment Department Jilin Agriculture University Changchun 130118 P. R. China

The powder crystals of RMnO3（R=Er, Tm） with hexagonal and orthorhombic structures were prepared under hydrothermal conditions. The different structural phases of the title compounds were controllably formed from different kinds of precursors at different reaction temperatures. All of the samples were characterized by powder X-ray diffraction, scanning electron microscopy, inductively coupled plasma analysis, and variable temperature magnetic susceptibility. Their structures were refined by Rietveld method from powder X-ray diffraction data. The measurement of magnetic behavior shows antiferromagnetic orderings at Neel temperatures around 80 and 40 K for the hexagonal and orthorhombic phases, respectively.

关键词： Manganate RMnO3 Antiferromagnetism Hydrothermal synthesis

Crystallization Behavior of Polymer Derived Silicon Carbide Sintered Through Microwave Heating Technique

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Journal of Wuhan University of Technology(Materials Science) 2017年第6期32卷 1368-1373页

作者：熊俊 huang Qing School of Materials Science and Engineering Tianjin University Tianjin 300072 China

A self-crosslinkable liquid highly branched polycarbosilane（LHBPCS） with 5.07% vinyl group and a C/Si ratio of 1.33 was used as the precursor to prepare Si C ceramic material. Microwave heating technique and conventional heating method were applied for the heating treatment process. It was found that, compared with conventional heating method, microwave heating technique could enhance the crystallinity of Si C ceramic material with small grain size at much lower curing temperature and within shorter time. In addition, the SiO_2 additive could lead to less α-Si C and excess carbon, but worsen the crystallinity of β-Si C in the final samples.

关键词： liquid highly branched polycarbosi'ane microwave heating crystallization behavior β-SiC

The effect of metal electron cloud on the luminescence characteristics of organic ligands:An experimental and theoretical investigation

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Chinese Science Bulletin 2011年第6期56卷 479-483页

作者： ZHANG FuJun LIU XiaoJun huang feng ZHUO ZuLiang LU LiFang XU Zheng WANG YongSheng TAO XuTang BIAN WenSheng TANG WeiHua Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University) Ministry of Education Beijing 100044 China State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China Beijing National Laboratory for Molecular Sciences Beijing 100109 China Key Laboratory for Soft Chemistry and Functional Materials of Ministry Education Nanjing University of Science and Technology Nanjing 210094 China

The luminescence processes of metal complexes are complicated by intramolecular charge (energy) transfer from the metal to the ligand or from the ligand to the metal. The charge transfer strongly influences the excited state of the ligand and its luminescence characteristics. The luminescence characteristics of tris(8-hydroxyquinoline) aluminum (Alq3) and tris(8-hydroxyquinoline) gallium (Gaq3) are investigated to reveal the effect of the metal ion on the ligand. Emission from the complexes shows a significant red shift as the size of the metal ion increases from Al to Ga because of more efficient charge transfer from the metal to the ligand. Theoretical calculations on the structure and transition characteristics of the excited states of Alq3 and Gaq3 were performed. The calculated emission wavelength agrees with the experimental value and the effect of the metal electron cloud on the emission wavelength is clarified.

关键词：金属配合物有机配体发光特性电子云实验值金属离子效应电荷转移羟基喹啉

椎体骨皮质强化差异对骨质疏松性椎体压缩性骨折生物力学的影响

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中国组织工程研究 2025年第21期29卷 4430-4438页

作者：方伟黄兴桦屈波杨红胜重庆市云阳县中医院骨伤科重庆市404500 成都医学院附属第一医院骨科四川省成都市610500

背景:骨质疏松性椎体压缩性骨折经皮椎体成形过程中骨水泥在椎体内的骨皮质强化区域对脊柱生物力学及临床疗效有重要影响,但以往研究大多局限于二维层面。目的:采用有限元分析法探讨经皮椎体成形过程中骨水泥在椎体三维层面内骨皮质强... 详细信息

背景:骨质疏松性椎体压缩性骨折经皮椎体成形过程中骨水泥在椎体内的骨皮质强化区域对脊柱生物力学及临床疗效有重要影响,但以往研究大多局限于二维层面。目的:采用有限元分析法探讨经皮椎体成形过程中骨水泥在椎体三维层面内骨皮质强化差异对骨质疏松性椎体压缩性骨折椎体、邻近椎间盘及终板生物力学分布的影响,以评估其效果。方法:建立T12椎体骨质疏松性压缩性骨折行经皮椎体成形治疗的有限元模型,从横断面、矢状面、冠状面对骨水泥有无皮质强化情况进行分组分析,研究不同体位变化下,骨皮质强化对T12椎体松质骨、皮质骨、T11/T12椎间盘、T12/L1椎间盘、T11下终板、L1上终板生物力学的影响。结果与结论:(1)在垂直压缩力作用下,经皮椎体成形过程中有或无骨水泥皮质强化在不同体位变化下除伤椎皮质骨以外结构应力变化均不明显;(2)伤椎皮质骨Von Mises应力值在人体前屈、左/右侧弯和左/右轴向旋转时差异显著,同一平面内骨皮质完全强化组较无骨皮质强化组最大Von Mises应力值明显变小,随着骨皮质强化越广泛Von Mises应力值整体呈下降趋势;(3)提示行经皮椎体成形治疗时,横断面内骨水泥应尽量广泛对称水平分布于椎体骨皮质边缘,矢状面内骨水泥应广泛纵向分布且靠近上下终板及前后壁,冠状面内骨水泥应广泛分布于中线两侧同时对称接触上下终板及侧壁,可有效避免伤椎再骨折风险且不增加邻椎骨折、残留盘源性疼痛风险。

关键词：经皮椎体成形骨皮质强化骨质疏松性椎体压缩性骨折邻近椎间盘终板三维有限元分析生物力学

Safety and efficacy of microwave ablation for periductal hepatocellular carcinoma with intraductal cooling of the central bile ducts through a percutaneous transhepatic cholangial drainage tube

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Journal of Interventional Medicine 2019年第2期2卷 84-90页

作者： Naijian Ge Jian huang Zhiyong Shi Xiaohe Yu Shuqun Shen Xiaobing Wu jing Zhou Qinqin Hang Yefa Yang Mini-invasive Intervention Center Eastern Hepatobiliary Surgery HospitalThe Second Military Medical University225 Changhai RoadShanghaiChina The No.1 Department of Biliary Surgery Eastern Hepatobiliary Surgery HospitalThe Second Military Medical University225 Changhai RoadShanghaiChina Medical Department Health Insurance Office Eastern Hepatobiliary Surgery HospitalThe Second Military Medical University225 Changhai RoadShanghaiChina

Background and aims:Biliary thermal injury caused by microwave ablation(MWA)for a hepatocellular carcinoma(HCC)close to the central bile ducts always results in severe complications and leads to *** studies have demonstrated that intraductal cooling of the biliary tract with chilled saline during thermal ablation can successfully prevent these *** this study,we present a novel bile duct cooling technique through a percutaneous transhepatic cholangial drainage(PTCD)tube for preventing biliary thermal injury caused by MWA,and compare the feasibility and safety of the intraductal cooling technique when performed with a PTCD tube and with an endoscopic nasobiliary drainage(ENBD)***:Participants were randomly assigned to undergo MWA of HCC with intraductal chilled saline perfusion through a PTCD tube or an ENBD *** main study outcomes were bile duct complications related to MWA and local tumor recurrence,p value<0.05 was considered to indicate a statistically significant ***:A total of 23 patients with an HCC(23 nodules)close to a central bile duct were enrolled in this *** these patients,12 had a PTCD tube and 11 had an ENBD tube placed into the hepatic duct close to the *** were no PTCD-and ENBD-related mortality *** was no complication related to the PTCD procedure;however,3 patients(27.27%)developed acute pancreatitis and 1 patient(9.09%)had hemorrhage in the ENBD group(p=0.037).One patient(8.33%)in the PTCD group had bile leakage and 2 patients(18.18%)in the ENBD group developed a *** 5 years,1 patient in the PTCD group and 2 patients in the ENBD group had local *** was no significant difference in local recurrence,nonlocal hepatic recurrence,mortality rate,or median cumulative overall survival between the 2 ***:The intraductal cooling technique using a PTCD tube is a feasible and effective method for preventing bile duct thermal injury caused by MWA for

关键词： Microwave ablation Hepatocellular carcinoma Biliary complications Intraductal cooling technique Percutaneous transhepatic cholangial drainage

Resistance of barley varieties to Heterodera avenae in the Qinghai–Tibet Plateau,China

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Journal of Integrative Agriculture 2022年第5期21卷 1401-1413页

作者： YAN Jia-hui JIA Jian-ping JIANG Li-ling PENG De-liang LIU Shi-ming HOU Sheng-ying YU jing-wen LI Hui-xia huang Wen-kun Key Laboratory of Agricultural Integrated Pest Management Qinghai Academy of Agriculture and Forestry SciencesXining 810016P.R.China State Key Laboratory for Biology of Plant Diseases and Insect Pests/Institute of Plant Protection Chinese Academy of Agricultural SciencesBeijing 100193P.R.China College of Plant Protection Gansu Agricultural UniversityBiocontrol Engineering Laboratory of Crop Diseases and Pests of Gansu ProvinceLanzhou 730070P.R.China

The cereal cyst nematode,Heterodera avenae,is one of the most economically important pathogens impacting the worldwide production of cereals and is widely distributed in more than 16 regions in *** present study used the numbers of nematodes inside the plant roots to evaluate the resistance/susceptibility of different subpopulations of barley Hordeum vulgare(QH2R,QH6R and TB2R)to *** under field and pot *** development in two highly resistant varieties was also evaluated by in vivo experiment and microscopic *** of 186selected varieties showed the numbers of susceptible varieties identified with the number of females/cysts per plant(NFP)method were significantly higher than those identified with the Pf/Pi ratio(PPR)method,which indicated that the NFP method rather than the PPR method is more reliable to evaluate the resistance of *** field and pot experiment results indicated that the QH2R subpopulation had lower females/cysts numbers than QH6R and TB2R subpopulations,and eight HR varieties(Sunong 7617,Sunong 7635,Dongyuan 87-14,Rudong 14-46,Rudong 87-57,Rudong 87-8-45,Rudong 88-14-2,and Rudong 88-67-1)were identified in QH2R,with the NFP numbers below *** microscopic observation of nematode development suggested that *** often penetrated less into highly resistant varieties(Sunong 7635 and Dongyuan 87-14)and more frequently failed to develop into females than the susceptible *** promising resistant varieties identified in the present research might be helpful for breeders to develop CCN-resistant cultivars and control *** populations effectively at low costs.

关键词： Heterodera avenae barley varieties resistance evaluation number of females/cysts per plant(NFP)