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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 121-125页

作者： hai-jun su jun zhang lin liu heng-zhi fu State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi＇an 710072 China

Oxide eutectic ceramic in situ composites have attracted significant interest in the application of high-temperature structural materials because of their excellent high-temperature strength,oxidation and creep resistance,as well as outstanding microstructural *** directionally solidified ternary Al2O3/YAG/ZrO2 hypereutectic in situ composite was successfully prepared by a laser zone remelting method,aiming to investigate the growth characteristic under ultra-high temperature *** microstructures and phase composition of the as-solidified hypereutectic were characterized by using scanning electron microscopy（SEM）,energy dispersive spectroscopy（EDS）,and X-ray diffraction（XRD）.The results show that the composite presents a typical hypereutectic lamellar microstructure consisting of fine Al2O3 and YAG phases,and the enriched ZrO2 phases with smaller sizes are randomly distributed at the Al2O3/YAG interface and in Al2O3 *** power and scanning rate strongly affect the sample quality and microstructure ***,coarse colony microstructures were also observed,and their formation and the effect of temperature gradient on the microstructure were discussed.

关键词： eutectics ceramic materials microstructure thermal gradients remelting solidification

Effects of grain refinement on cast structure and tensile properties of superalloy K4169 at high pouring temperature

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China Foundry 2016年第2期13卷 101-106页

作者： Zi-qi Jie jun zhang Tai-wen Huang lin liu hai-jun su Yan-li Shi heng-zhi fu State Key Laboratory of Solidification ProcessingNorthwestern Polytechnical UniversityXi'an 710072China Xi'an Jiaotong University City College Xi'an 710072China

In order to improve the filling ability of large complex thin wall castings, the pouring temperature should be increased, but this will result in the grain coarsening. To overcome this problem, two kinds of grain refiners of Co-Fe-Nb and Cr-Fe-Nb ternary alloys, which contain high stability compound particles, were prepared. The effects of the refiners on the as-cast structures and tensile properties of the K4169 superalloy with different casting conditions were studied by analyzing specimens 110 mm long and 20 mm in *** showed that the mixture addition of the two refiners in the melt of K4169 can reduce the columnar grain region and decrease the equiaxed grain size greatly. After refinement, the amount of Laves phase decreases and its morphology changes from island to blocky structure. The carbides in the fine grain samples are fine and dispersive. Meanwhile, the porosity in specimens is decreased due to grain refinement. As a result, the yield strength, ultimate strength and the elongation of the specimens are increased. The grain refinement mechanisms are also discussed.

关键词： superalloy K4169 grain refinement tensile properties

阻塞性睡眠呼吸暂停严重度评估参数及诊断技术

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生物化学与生物物理进展 2025年第1期52卷 147-161页

作者：付卓志吴亚岑李媚希尹平平林海军张甫杨宇祥湖南师范大学工程与设计学院长沙410081 湖南师范大学附属第一医院康复医学科长沙410005

阻塞性睡眠呼吸暂停(OSA)是一种日益广泛的睡眠呼吸障碍性疾病,是很多高风险慢性疾病如高血压、冠心病、中风、心律不齐和糖尿病的独立危险因素,具有潜在的致命性。OSA防治的关键是早诊断、早治疗,因此OSA的评估与诊断技术成为研究热点... 详细信息

阻塞性睡眠呼吸暂停(OSA)是一种日益广泛的睡眠呼吸障碍性疾病,是很多高风险慢性疾病如高血压、冠心病、中风、心律不齐和糖尿病的独立危险因素,具有潜在的致命性。OSA防治的关键是早诊断、早治疗,因此OSA的评估与诊断技术成为研究热点。本文综述了OSA的严重度评估参数与诊断技术的研究进展,并探讨了未来发展的方向。在OSA严重度评估参数方面,呼吸暂停低通气指数(AHI)作为黄金标准,其与呼吸暂停低通气持续时间百分比(AH%)、最低氧饱和度(LSpO2)、心率变异性(HRV)、氧减指数(ODI)及新兴的生物标志物,共同构成了多维度评估体系。OSA诊断技术包括金标准多导睡眠监测(PSG)、便捷的家庭睡眠监测(HSAT)和心肺耦合(CPC)技术;而机器学习与人工智能作为新兴的诊断技术,由于其智能化和高准确度而日益受到青睐;此外,标准化问卷和Epworth嗜睡评分(ESS)、影像学检查和声音检测技术也为OSA诊断提供了支持。多模态融合、跨学科的整合研究、个性化诊疗模式的构建以及高新技术在临床应用中的推广将成为OSA评估与诊断领域的发展趋势。

关键词：阻塞性睡眠呼吸暂停评估参数诊断技术

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Simulation of stray grain formation in Ni-base single crystal turbine blades fabricated by HRS and LMC techniques

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China Foundry 2017年第2期14卷 75-79页

作者： Ya-feng Li lin liu Tai-wen Huang Miao Huo jun-sheng He jun zhang heng-zhi fu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China

The simulation models of the thermal and macrostructural evolutions during directional solidification of Ni-base single crystal(SX) turbine blades under high rate solidification(HRS) and liquid metal cooling(LMC) have been constructed using Pro CAST software, coupled with a 3D Cellular Automaton Finite Element(CAFE) model. The models were used to investigate the tendencies of stray grain(SG) formation in the platform region of turbine blades fabricated by HRS and LMC techniques. The results reveal that the LMC technique can prohibit SG formation by smoothing the concaved isotherm and in turn alleviating the undercooling in the platform ends to let the dendrites fill up the undercooled zone before SG nucleation. The simulation results agreed well with the experimental results, indicating that these models could be used to analyze the macrostructural evolution or to optimize process parameters to suppress SG formation. Using these models, the critical withdrawal rate for casting SX turbine blades without SG formation were determined to be around 75 μm·s^(-1) and 100 μm·s^(-1) for HRS and LMC respectively, suggesting that LMC can be used as an efficient technique in fabricating SX turbine blades without any SG defect formation.

关键词： thermal profile macrostructural evolution simulation HRS LMC stray grain

High-capacity potassium ion storage mechanisms in a soft carbon revealed by solid-state NMR spectroscopy

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Rare Metals 2022年第11期41卷 3752-3761页

作者： Jing-heng Han Jia He Qi-Yao Zou Jie zhang zhi Yang zhi-Wei Zhao Hui-Xin Chen Hong-jun Yue Da-Wei Wang hai-Chen lin Hao-Dong liu Gui-Ming Zhong zhang-Quan Peng College of Chemistry and Material Science Fujian Normal UniversityFuzhou350000China CAS Key Laboratory of Design and Assembly of functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China Xiamen Key Laboratory of Rare Earth Photoelectric functional Materials Xiamen Institute of Rare-Earth MaterialsHaixi InstitutesChinese Academy of SciencesXiamen361021China Laboratory of Advanced Spectro-Electrochemistry and Li-Ion Batteries Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China Key Laboratory of Automobile Materials of Ministry of Education&School of Materials Science and Engineering Jilin UniversityChangchun130025China Chemical Engineering University of California San DiegoLa JollaSan DiegoCA92093USA

Carbon materials are crucially important for the realization of potassium-ion ***,the potassium storage mechanisms in various carbon materials are incompletely ***,solid-state ^(13)C nuclear magnetic resonance(NMR) spectroscopy coupled with Raman and X-ray diffraction(XRD) techniques are employed to study the reaction mechanism in a soft carbon *** is revealed that the insertion of potassium ions into the soft carbon firstly induces a transformation of the disordered region to short-range ordered stacking,involving both the pristine local unorganized and organized carbon ***,potassium ions intercalate into the rearranged carbon structure,finally producing the nano-sized KC_(8).Moreover,a remarkable c apacity of 322 mAh·g^(-1) with a low mid potassiation voltage of sults suggest that regulating the disordered stacking region in the turbostratic structure of soft carbon is a critical issue for further improving the potassium storage performance.

关键词： Reaction mechanism Soft carbon Solid-state nuclear magnetic resonance(NMR) Anode Potassium-ion batteries(PIBs)

2022 roadmap on hydrogen energy from production to utilizations

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Rare Metals 2022年第10期41卷 3251-3267页

作者： Zheng-Xuan Yang Xiu-Gang Li Qi-Lu Yao zhang-Hui Lu Ning zhang jun Xia Kai Yang Yu-Qing Wang Kan zhang hai-Zhen liu liu-Ting zhang Huai-jun lin Qing-jun Zhou Fang Wang zhi-Ming Yu Jian-Min Ma School of Physics and Electronics Hunan UniversityChangsha410082China College of Material and Chemical Engineering Tongren UniversityTongren554300China Key Laboratory of functional Small Molecules for Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China School of Materials Science and Engineering Central South UniversityChangsha410083China School of Chemistry and Chemical Engineering Jiangxi University of Science and TechnologyGanzhou341000China School of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing210094China Guangxi Novel Battery Materials Research Center of Engineering Technology Guangxi Key Laboratory of Processing for Non-Ferrous Metallic and Featured MaterialsGuangxi Colleges and Universities Key Laboratory of Novel Energy Materials and Related TechnologySchool of Physical Science and TechnologyGuangxi UniversityNanning530004China School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang212003China Institute of Advanced Wear and Corrosion Resistance and functional Materials Jinan UniversityGuangzhou510632China College of Science University of Shanghai for Science and TechnologyShanghai200093China School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun130022China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu611731China

Hydrogen has been always the hot topic,which drives a lot of researchers to study and explore hydrogenrelated projects and *** first subfield is hydrogen production with green and cost-effective *** methods have been intensively used for high-efficient hydrogen production,i.e.,catalytic chemical hydrogen generation,electrocatalytic hydrogen evolution,photocatalytic hydrogen evolution,photo-electrocatalytic hydrogen *** of them are driven by various ***,the hydrogen storage is also an important question,which is also a present research hot topic,although the history is long with several *** fuel cells have also obtained great attention due to the zero *** related research mainly focuses on the cell systems and electrocatalysts *** this background,we invite some excellent research groups to write this progress on hydrogen from production to ***,we believe that this roadmap on hydrogen can give some useful guidance in future research.

关键词： Hydrogen Hydrogen production Hydrogen generation Hydrogen evolution Hydrogen storage fuel cells

Preparation and properties of ZrO_(2)-strengthened porous mullite insulation materials using Y_(2)O_(3) additive

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Journal of Iron and Steel Research International 2024年第6期31卷 1514-1521页

作者： Wang-zhi Yu Yi-hong Shi Ping liu Yong-wan Wu Cheng-hao Song Xian-gong Deng Xiang Ding Song-lin Ran Yi zhang hai-jun zhang hai-liang Deng Advanced Ceramics Research Center School of Materials Science and EngineeringAnhui University of TechnologyMa'anshan 243002AnhuiChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

ZrO_(2)-strengthened porous mullite insulation materials were prepared by foaming technology utilizing ZrSiO_(4) and Al_(2)O_(3) as primary materials and Y_(2)O_(3) as an *** effects of Y_(2)O_(3) contents on the phase composition,microstructure,mechanical properties,and heat conductivity of the porous mullite insulation materials were investigated.A suitable Y_(2)O_(3) content could promote phase transition of monoclinic ZrO_(2)(m-ZrO_(2))to tetragonal ZrO_(2)(t-ZrO_(2)),reduce pore size,and improve the strengths of as-prepared *** cold crushing strength and bending strength of as-prepared specimens with a 119µm spherical pore size using 6 wt.%Y_(2)O_(3) were 35.2 and 13.0 MPa,respectively,with a heat conductivity being only 0.248 W/(m K).

关键词： Porous mullite insulation material Zirconium oxide Y_(2)O_(3) Mechanical property Heat conductivity

Cholangiojejunostomy for multiple biliary ducts in living donor liver transplantation: A case report

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World Journal of Clinical Cases 2021年第11期9卷 2649-2654页

作者： Fei Xiao Li-Ying sun lin Wei zhi-Gui Zeng Wei Qu Ying liu hai-Ming zhang zhi-jun Zhu Liver Transplantation Center National Clinical Research Center for Digestive DiseasesBeijing Friendship HospitalCapital Medical UniversityBeijing 100050China Department of Organ Transplantation Liao Cheng People's HospitalLiaocheng 252000Shandong ProvinceChina Clinical Center for Pediatric Liver Transplantation Capital Medical UniversityBeijing 100050China Beijing Key Laboratory of Tolerance Induction and Organ Protection in Transplantation Capital Medical UniversityBeijing 100050China Department of Intensive Care Unit Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China Liver Transplantation Center National Clinical Research Center for Digestive DiseasesCapital Medical UniversityBeijing 100050China

BACKGROUND Laparoscopic living donor hepatectomy(LLDH)has been successfully carried out in several transplant *** reconstruction is key in living donor liver transplantation(LDLT).Reliable biliary reconstruction can effectively prevent postoperative biliary stricture and *** preoperative magnetic resonance cholangiopancreatography and intraoperative indocyanine green cholangiography have been shown to be helpful in determining optimal division points,biliary variability and limitations associated with LLDH,multiple biliary tracts are often encountered during surgery,which inhibits biliary reconstruction.A reliable cholangiojejunostomy for multiple biliary ducts has been utilized in *** procedure provides a reference for multiple biliary reconstructions after *** suMMARY A 2-year-old girl diagnosed with ornithine transcarbamylase deficiency required liver *** to the scarcity of deceased donors,she was put on the waiting list for *** father was a suitable donor;however,after a rigorous evaluation,preoperative magnetic resonance cholangiopancreatography examination of the donor indicated the possibility of multivessel variation in the biliary ***,a laparoscopic left lateral section was performed on the donor,which met the estimated graft-to-recipient weight *** intraoperative indocyanine green cholangiography,4 biliary tracts were confirmed in the *** was difficult to reform the intrahepatic bile ducts due to their openings of more than 5 mm.A reliable cholangiojejunostomy was,therefore,utilized:suture of the jejunum to the adjacent liver was performed around the bile duct openings with 6/0 absorbable *** the last follow-up(1 year after surgery),the patient was *** Intrahepatic cholangiojejunostomy is reliable for multiple biliary ducts after LLDH in LDLT.

关键词： Cholangiojejunostomy Living donor liver transplantation Laparoscopic left lateral section Multiple biliary ducts Treatment Case report

Preparation, microstructure and dislocation of solar-grade multicrystalline silicon by directional solidification from metallurgical-grade silicon

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Transactions of Nonferrous Metals Society of China 2012年第10期22卷 2548-2553页

作者：苏海军张军刘林傅恒志西北工业大学凝固技术国家重点实验室西安710072

A vacuum directional solidification with high temperature gradient was performed to prepare low cost solar-grade multicrystalline silicon （mc-Si） directly from metallurgical-grade mc-Si. The microstructure characteristic, grain size, boundary, solid-liquid growth interface, and dislocation structure under different growth conditions were studied. The results show that directionally solidified multicrystalline silicon rods with high density and orientation can be obtained when the solidification rate is below 60 μm/s. The grain size gradually decreases with increasing the solidification rate. The control of obtaining planar solid-liquid interface at high temperature gradient is effective to produce well-aligned columnar grains along the solidification direction. The growth step and twin boundaries are preferred to form in the microstructure due to the faceted growth characteristic of mc-Si. The dislocation distribution is inhomogeneous within crystals and the dislocation density increases with the increase of solidification rate. furthermore, the crystal growth behavior and dislocation formation mechanism of mc-Si were discussed.

关键词： multi-crystalline silicon metallurgical-grade silicon silicon solar cell directional solidification microstructure

Current Tracking on Effectiveness and Mechanisms of Acupuncture Therapy: A Literature Review of High-Quality Studies

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Chinese Journal of Integrative Medicine 2020年第4期26卷 310-320页

作者： YANG fu-ming YAO lin WANG Shen-jun GUO Yi XU zhi-fang zhang Chien-Hung zhang Kuo FANG Yu-xin liu Yang-yang Acupuncture Research Center Tianjin University of Traditional Chinese MedicineTianjin(301617)China Department of Acu-moxibustion and Tuina Changchun University of Traditional Chinese MedicineJilin(130000)China Department of Acu-moxibustion and Tuina Tianjin University of Traditional Chinese MedicineTianjin(301617)China Department of Traditional Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjin(301617)China

The scientific evidenee of acupuncture studies has been improved in recent years,and one of the important manifestations is that more and more acupuncture clinical trials and mechanism researches have been published in the source periodicals of Science Citation Index(SCI).This study summarized the dominant diseases of acupuncture focusing on of acupuncture efficacy and mechanisms,and discussed the existing problems,highlight!ng the directi on of future developme *** clinical studies were published in journals with journal impact factor(JIF)score of 10 or above,and majority of the basic researches had JIF scores of 5 to *** above literature were further divided according to the International Classification of Diseases(ICD).The most concerned diseases in these articles were neurological diseases,musculoskeletal system and connective tissue diseases,tumor and digestive system *** therapeutic effect and mechanism of acupuncture on each kind of disease were *** results showed that the therapeutic effect of acupuncture on nerve injury focused on the anti-oxidation pathway,neuroprotective and anti-inflammatory *** antiinflammatory effect also played an important role in the treatme nt of musculoskeletal *** an algesic effect was underlined in most of these *** trials were well carried out on acupuncture curative effect of tumor complications and side effects of chemo-radiotherapy,but the potential mechanisms have not been ***-visceral reflex was suggested to be strongly associated with the effects of acupuncture changing the motor activity of the gastrointestinal *** magnetic resonance imaging studies indicated that non-specific effects play important roles in acupuncture *** of evidenee have pointed out that the regulation of neuro-endocrine-immune networks may be a common switch of acupuncture on different nerve system diseases.

关键词： acupuncture clinical trials mechanism anti-inflammation neuro-endocrine-immune network