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One-pot Synthesis and Formation Mechanism of Prisms-built VO2(M) with Hypersensitive Phase-transition Hysteresis

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Chinese Journal of Structural Chemistry 2021年第8期40卷 999-1004,968页

作者： li xiong-jian YANG Shui-Jin Hubei Key Laboratory of Pollutant Analysis&Reuse Technology College of Chemistry and Chemical EngineeringHubei Normal UniversityHuangshi 435002China

Prisms-built VO_(2)(M)micro-nanostructures with narrow hysteresis width of 2.7℃were successfully synthesized using V_(2)O_(5)-H_(2)C_(2)O_(4)-H2O system by one-pot hydrothermal *** structure,composition,phase transition and optical properties were characterized by XRD,SEM,DSC,and variable-temperature *** results revealed the prism had well-defined six facets and entire smooth surface with lengths of about 500 nm and thicknesses of around 100 *** prisms were connected to each other through the apical *** prismatic VO_(2)(M)showed excellent phase transition and optical switching properties that would be beneficial for highly sensitive electrical/optical devices or other *** possible formation mechanism of prismatic VO_(2)(M)was proposed via time-dependent SEM images and XRD ***,the influence of the amount of H_(2)O on the final product was discussed in detail.

关键词： VO_(2)(M) optical properties hysteresis width one-pot synthesis

Effect of Counterface Material on Friction and Wear Behavior of Ni-Cr-W-Al-Ti-MoS_2 Composites

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Chinese Journal of Aeronautics 2006年第B12期19卷 74-77页

作者： li jian-liang xiong Dang-sheng WAN Yi Department of Materials Science and Engineering Nanfing University of Science and Technology Nanjing 210094 China

Ni-Cr-W-Al-Ti-MoS2 self-lubricating composites were prepared through the powder metallurgy （P/M） method. Their friction properties were investigated by a pin-on-disk tribometer in the range from the room temperature to 600 ℃. Alumina, silicon nitride and nickel-iron-sulfide alloys were selected as the counterface materials. Results indicate that the lowest friction coefficients under 0.22 can be obtained at 600℃ when rubbed against alumina. When rubbed against nickel-iron-sulfide alloys, are presented the lowest wear rates in the magnitude of 10^-6 mm^3/N-m, one order of magnitude lower than those when rubbed against ceramics. In the case of three rubbing pairs, the wear rates of the composite containing MoS2 present themselves inversely proportional to friction coefficients. With alumina ceramics used as a counterface, transfer films and glaze layers will form on the contact surface playing a main role in lubrication at high temperatures. However, when silicon nitride and nickel-iron-sulfide alloy are used, the lubricating transfer films appear not to be prominent.

关键词： powder metallurgy (P/M) high temperature solid lubrication Ni-based composite

Analysis of blade vibration response induced by rotating stall in axial compressor

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航空动力学报 2012年第10期27卷 2269-2277页

作者： Zhang, Ming-Ming Hou, An-Ping li, jian-xiong Yao, Juan Chen, Ying-Xiu School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China

An experimental and numerical study was conducted to investigate the forced response of blade vibration induced by rotating stall in a low speed axial *** have been made of the transient stalling process in a low speed axial compressor *** CFD study was performed using solution of 3-dimensional Navier-Stokes equations,coupled with structure finite element models for the blades to identify modal shapes and structural deformations *** between fluid and structure were managed in a coupled manner,based on the interface information exchange until convergence in each time *** on the rotating stall measurement data obtained from a low speed axial compressor,the blade aeroelastic response induced by the rotating stall flow field was analyzed to study the vibration characteristics and the correlation between the *** this approach,good agreement between the numerical results and the experimental data was *** flow phenomena were well captured,and the results indicate that the rotating field stall plays a significant role in the blade vibration and stress affected by the flow excitation.

关键词： compressor rotating stall blade forced response CFD fluid-structure interaction

Mechanisms of secondary damage to the thalamic nucleus and substantia nigra in an adult hypertensive rat model following middle cerebral artery occlusion

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Neural Regeneration Research 2010年第11期5卷 853-858页

作者： li xiong jian Yu Songjie liao Shihui Xing Zhan Zhao Jinsheng Zeng Stroke Center and Department of Neurology First Affiliated Hospital Sun Yat-Sen University Guangzhou 510080 Guangdong ProvinceChina

BACKGROUND： Following ischemia, apoptosis is observed at the ipsilateral ventropostenor thalamic nucleus and substantia nigra, which are distant from, but connected to, the ischemic cerebral cortex, in animals with normotension. However, secondary brain damage in hypertension has not been clearly investigated. OBJECTIVE： The present study determined whether neuronal apoptosis is associated with neuronal loss in the ipsilateral ventroposterior thalamic nucleus and substantia nigra following cortical ischemia in adult hypertensive rats. Results should provide options for determining a time window for anti-apoptotic therapy. DESIGN, TIME AND SETTING： All experimental procedures in this randomized, controlled trial were conducted at the Neurological Laboratory of the First Affiliated Hospital of Sun Yat-sen University of China between October 2006 and July 2008. MATERIALS： Monoclonal primary antibodies specific to mouse anti-rat microtubule-associated protein 2 and glial fibrillary acidic protein were respectively purchased from Sigma Chemical, USA and BD Pharmingen, USA. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling （TUNEL） detection kits were purchased from Roche Applied Science, Switzerland and Upstate, USA, respectively. METHODS： A total of 64 male, Sprague Dawiey rats, aged 60-90 days, were equally and randomly divided into middle cerebral artery occlusion and sham surgery groups. Renovascular hypertension was established in both groups by renal artery occlusion. Right distal middle cerebral artery occlusion was performed by electrocoagulation in the middle cerebral artery occlusion group. MAIN OUTCOME MEASURES： Microtubule-associated protein 2 and glial fibrillary acidic protein were detected by immunohistochemistry, and apoptotic cells were observed by TUNEL assay. The stainings were separately detected in the ipsilateral ventroposterior thalamic nucleus and substantia nigra. RESULTS： During the 4 weeks followin

关键词： ventroposterior thalamic nucleus substantia nigra apoptosis rats cerebral infarction neural regeneration

Responses of Earthworms to Organic Matter at Different Stages of Decomposition

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Pedosphere 2009年第3期19卷 382-388页

作者： li jian-xiong ZHANG Wei-Xin liAO Chong-Hui YANG Yue-Ping FU Sheng-Lei Guangdong Entomological Institute Guangdong Academy of Sciences Guangzhou 510260 （China） Institute of Ecology South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 （China） Graduate University of the Chinese Academy of Sciences Beijing 100049 （China）

This study was conducted to examine the responses of earthworms to soil organic matter and litter at different decomposition stages and their contributions in litter decomposition processes in southern subtropical areas of China. Two plantations were selected as the study sites: Site I was dominated by the exotic endogeic earthworm species Ocnerodrilus occidentalis; Site II was dominated by epigeic species Amynthas corticis. After the fallen litter and earthworms were removed or expelled, four treatments were set up as: reserving the top soil (0–5 cm, equal to H layer) (H), removing the top soil and adding fresh litter (Le), removing the top soil and adding semi-decomposed litter (li), and a control with no top soil nor any litter (CK). Five randomized blocks that were enclosed with nylon nets on the top were set up in each site, and then the four treatments were arranged randomly in each block. After 2–3 months, earthworms were collected using the formalin method. The results showed that Ocnerodrilus occidentalis preferred Treatment H though it was found in Treatments Le and li as well; Amynthas corticis preferred Treatment li though sometimes it also appeared in Treatment H; and Amynthas sp., another epigeic species, was mainly present under Treatment Le and only appeared in Treatment H occasionally. These findings confirmed that earthworm species belonging to different ecological groups had different responses to organic matter at different decomposition stages. The impacts of earthworm communities dominated by O. occidentalis mainly appeared at the later periods of litter decomposition.

关键词： decomposition stage earthworm litter soil organic matter

CORRECTIVE SURGERY OF CONGENITAL SCOliOSIS WITH TYPE II SPliT SPINAL CORD MALFORMATION

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Chinese Medical Sciences Journal 2006年第1期21卷 48-52页

作者： Bin Yu Yi-peng Wang Gui-xing Qiu jian-guo Zhang Jia-yi li jian-xiong Shen Xi-sheng Weng Department of Orthopedic Surgery Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730

Objective To investigate the corrective results of congenital scoliosis with type II split spinal cord *** By reviewing the medical records and roentgenograms of congenital scoliosis patients with type II split spinal cord malformation that underwent corrective surgery, septum location and length, curve type, coronal and sagittal Cobb’s angles, apical vertebral rotation and translation, and trunk shift were measured and *** A total of 23 congenital scoliosis patients with type II split spinal cord malformation were studied, 6 cases were due to failure of segmentation, 8 cases due to failure of formation, and the remaining 9 cases due to mixed *** fibrous septums were located in the thoracic spine in 8 patients, lumbar spine in 4 patients, thoracic and lumbar spine in 10 patients, and from cervical to lumbar spine in 1 *** septum extended an average of 4.9 *** surgeries included anterior correction with instrumentation in 2 patients, posterior correction with instrumentation in 11 patients, anterior release and posterior correction with instrumentation in 6 patients, anterior and posterior resection of the hemivertebra and posterior correction with instrumentation in 4 *** pre- and postoperative coronal Cobb’s angles, apical vertebral translations, apical vertebral rotations, trunk shifts were 61.9° and 32.5°(Pliosis with type II split spinal cord malformation, positive correction results with no neurological complication may be obtained without resection of the fibrous septum.

关键词： scoliosis spinal dysraphism congenital disorders spinal cord myelodysplasia

Applied technique of the cemented fill with fly ash and fine-sands

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Journal of Central South University 2001年第3期13卷 189-192页

作者： WANG Xin-ming,li jian-xiong,FAN Ping-zhi (College of Resources, Environment and Civil Engineering, Central South Universi ty, Changsha 410083, China) College of Resources Environment and Civil Engineering Central South University Changsha China

Traditional stabilization of backfilling material is done by using Portland cement. However, the high price of cement forced mining engineer s to seek cheaper binding materials. Fly ash, which is the indus- trial wast e from thermal power plant, possess the potential activity of jellification, and can b e used in cemented fill as a partial substitute for cement to reduce the fill co s t. Tests were done during the past few years in Xinqiao Pyrite Mine and Phoenix Copper Mine to determine the technology parameters and the suitable content of f ly ash. Specimens with different cement/fly/ash tailings (sands) ratios were tes ted to obtain the strength values of the fill mass based on the analyses of both the chemical composition and physical and mechanical properties of fly ash . The compressive strength of specimens with a ratio of 1∶2∶8 (cement to fly ash to tailings ) can reach 2 MPa after 90 d curing, totally meeting the requiremen t of artificial pillar and reducing the fill cost by 20%-30%.

关键词： fly ash cementing agent cemented fill replacement

Protection　of　L－arginine　against　lysophosphatidy　lcholine－inducedmy　ocardi　alinjury　inisolated　ratheart

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中国药理学与毒理学杂志 1996年第2期 6-9页

作者： TANG Yu-Hai, PENG Chang-Fu, li Yuan-jian 2, xiong Yan (Department of Pharmacology, Hunan Medical University, Changsha 410078)

在离体大鼠心脏观察了Ｌ－精氨酸对溶血性磷脂酰胆碱（ＬＰＣ）损伤心肌作用的影响．ＬＰＣ（５μｍｏｌ·Ｌ－１）引起心率减慢，冠脉流量减少，心脏功能降低（ＬＶＰ和ＬＶｄｐ／ｄｔｍａｘ下降）及肌酸激酶（ＣＰＫ）释放增加．３０... 详细信息

在离体大鼠心脏观察了Ｌ－精氨酸对溶血性磷脂酰胆碱（ＬＰＣ）损伤心肌作用的影响．ＬＰＣ（５μｍｏｌ·Ｌ－１）引起心率减慢，冠脉流量减少，心脏功能降低（ＬＶＰ和ＬＶｄｐ／ｄｔｍａｘ下降）及肌酸激酶（ＣＰＫ）释放增加．３０μｍｏｌ·Ｌ－１Ｌ－精氨酸能促进心率恢复，增加冠脉流量和改善心脏功能，但仅ＬＶｄＰ／ｄｔｍａｘ恢复显示统计学差异；３００μｍｏｌ·Ｌ－１Ｌ－精氨酸能显著改善心脏功能，促进心率和冠脉流量的恢复，减少ＣＰＫ释放．结果提示：Ｌ－精氨酸对ＬＰＣ所致心肌损伤具有一定的保护作用．

关键词：精氨酸溶血性磷脂酰胆碱心脏大鼠

Compound control for speed and tension multivariable coupling system of reversible cold strip mill

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Journal of Central South University 2015年第2期22卷 529-538页

作者：方一鸣刘乐李建雄常茹 Key Laboratory of Industrial Computer Control Engineering of Hebei Province(Institute of Electrical Engineering Yanshan University) National Engineering Research Center for Equipment and Technology of Cold Strip Rolling(Yanshan University)

To weaken the nonlinear coupling influence among the variables in the speed and tension system of reversible cold strip mill, a compound control(CC) strategy based on invariance principle was proposed. Firstly, invariance principle was used to realize static decoupling between the speed and tension of reversible cold strip mill. Then, considering the influence caused by the time variation of steel coil radius and rotational inertia of the left and right coilers, as well as the uncertainties, a CC strategy that is composed of extended state observer(ESO) and global sliding mode control(GSMC) with backstepping adaptive was proposed,which further realized dynamic decoupling and coordination control for the speed and tension system. Theoretical analysis shows that the resulting closed-loop system is global bounded stable. Finally, the simulation was carried out on the speed and tension system of a 1422 mm reversible cold strip mill by using the actual data, and through the comparison of the other control strategies, validity of the proposed CC strategy was shown by the results.

关键词： reversible cold strip mill speed and tension system decoupling invariance principle compound control extended state observer global sliding mode control