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Friction and Wear Behavior of GCr15 Under Multiple Movement Condition

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Journal of China University of Mining and Technology 2005年第3期15卷 167-171页

作者： wang shi-bo GE shi-rong LI Wei wang Qing-liang School of Mechatromcs Engmeering China University of Mining and Technology Xuzhou Jiangsu 221008 China School of Material Science and Engineering China UniversiO of Mining and Technology Xuzhou Jiangsu 221008 China

Friction and wear of GCr15 under cross-sliding condition is tested on a ball-on-disc wear test machine. Thisresult shows that the cross-sliding of friction pair leads to different friction and wear behavior. For the condition de-scribed in this paper, the friction coefficients with ball reciprocating are smaller than that without ball *** friction coefficients increase with the increase of reciprocating frequency.. The wear weight loss of the ball sub-jected reciprocating sliding decreases, however, the wear weight loss of disc against the reciprocating ball increases. Incross-sliding friction, the worn surfaces of the ball show crinkle appearance along the circumferential sliding *** of small strip debris is formed along the plowing traces on the disc worn surface. The plowing furrow onthe disc surfaces looks deeper and wider than that without reciprocating sliding. The size of wear particles fromcross-sliding wear is larger than those without reciprocating sliding.

关键词： Friction coefficients Wear weight loss Cross-sliding Wear mechanism.

Comparison of the Wear Behavior of UHMWPE Lubricated by Human Plasma and Brine

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Journal of China University of Mining and Technology 2007年第3期17卷 335-340页

作者： wang shi-bo GE shi-rong NORM Gitis MICHAEL Vinogradov XIAO Jun Institute of Reliability Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Center for Tribology Incorporated Campell California 95008 USA

The effect of plasma and brine lubricants on the friction and wear behavior of UHMWPE were studied by using the geometry of a Si3N4 ball sliding on a UHMWPE disc under patterns of uni-directional reciprocation and bi-directional sliding motions. The worn surface and wear particles produced in these two lubricants were analyzed. Sliding motion pattern affected the friction coefficients lubricated with plasma,while seldom affected that lubricated with brine. UHMWPE lubricated with plasma showed about half of the wear rate of that lubricated with brine. The two rates were 0.75 pg/m and 2.19 pg/m for the two motion patterns,respectively. However,wear particles generated in plasma included a greater amount of small particles,compared to that in brine. In uni-directional reciprocation,the main wear mechanism is ploughing both in plasma and in brine. In bi-directional sliding modes,the significant characteristic is ripples on the worn surface in plasma,while there are oriented fibers on the worn surface in brine.

关键词： UHMWPE wear lubrication wear particles wear mechanism

Anti-oxidant and Anti-inflammatory Effects of Ethanol Extract from Polygala sibirica *** megalopha *** Lipopolysaccharide-Stimulated RAW264.7 Cells

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中国结合医学杂志:英文版 2023年第10期29卷 905-913页

作者： YANG Cheng-liu wang shi-bo HE Wen-ping LIU Jin-juan Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province School of Life ScienceJiangsu Normal UniversityXuzhouJiangsu Province221116China

Objective To investigate the anti-oxidant and anti-inflammatory effects of ethanol extract of Polygala sibirica *** megalopha Fr.(EEP)on RAW264.7 mouse *** RAW264.7 cells were pretreated with 0–200µg/mL EEP or vehicle for 2 h prior to exposure to 1µg/mL lipopolysaccharide(LPS)for 24 *** oxide(NO)and prostaglandin(PGE2)production were determined by Griess reagent and enzyme-linked immunosorbent assay(ELISA),*** mRNA levels of inducible nitric oxide synthase(iNOS),cyclooxygenase-2(COX-2),tumor necrosis factorα(TNF-α),interleukin-1beta(IL-1β),and IL-6 were determined using reverse transcription polymerase chain reaction(RT-PCR).Western blot assay was used to determine the protein expressions of iNOS,COX-2,phosphorylation of extracellular regulated protein kinases(ERK1/2),c-Jun N-terminal kinase(JNK),inhibitory subunit of nuclear factor Kappa B alpha(IκB-α)and *** was used to observe the nuclear expression of nuclear factor-κB p65(NF-κB p65).Additionally,the anti-oxidant potential of EEP was evaluated by reactive oxygen species(ROS)production and the activities of catalase(CAT)and superoxide dismutase(SOD).The 2,2-diphenyl-1-picrylhydrazyl(DPPH),hydroxyl(OH),superoxide anion(O2−)radical and nitrite scavenging activity were also *** The total polyphenol and flavonoid contents of EEP were 23.50±2.16 mg gallic acid equivalent/100 g and 43.78±3.81 mg rutin equivalent/100 *** EEP treatment(100 and 150µg/mL),there was a notable decrease in NO and PGE2 production induced by LPS in RAW264.7 cells by downregulation of iNOS and COX-2 mRNA and protein expressions(P<0.01 or P<0.05).Furthermore,with EEP treatment(150µg/mL),there was a decrease in the mRNA expression levels of TNF-α,IL-1βand IL-6,as well as in the phosphorylation of ERK,JNK and p38 mitogen-activated protein kinase(MAPK,P<0.01 or P<0.05),by blocking the nuclear translocation of NF-κB p65 in LPS-stimulated *** addition,EEP(100 and 150µg/mL)led

关键词： Polygala sibirica L.var megalopha Fr. anti-inflammatory anti-oxidant RAW264.7 cells lipopolysaccharide Chinese medicine

糖尿病足导致跟骨骨髓炎继发跟骨病理性鸟嘴样骨折的治疗效果

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中国骨伤 2024年第6期37卷 609-615页

作者：李炜峰高彦军王士波阮培灿邱元洲何昌强深圳市罗湖区中医院创伤骨科与足踝外科广东深圳518001

目的 :探讨万古霉素硫酸钙联合内固定治疗糖尿病足导致跟骨骨髓炎继发跟骨病理性“鸟嘴样”骨折的临床疗效。方法:回顾性分析2018年4月至2021年10月收治的5例糖尿病足导致跟骨骨髓炎继发跟骨病理性“鸟嘴样”骨折患者,男2例,女3例;年龄4... 详细信息

目的 :探讨万古霉素硫酸钙联合内固定治疗糖尿病足导致跟骨骨髓炎继发跟骨病理性“鸟嘴样”骨折的临床疗效。方法:回顾性分析2018年4月至2021年10月收治的5例糖尿病足导致跟骨骨髓炎继发跟骨病理性“鸟嘴样”骨折患者,男2例,女3例;年龄48~60岁;糖尿病病程5~13年;糖尿病足病程18~52 d;按Wagner分级均为Ⅲ级。所有患者根据病情Ⅰ期实施清创术,万古霉素骨水泥植入,负压吸引术;Ⅱ期使用万古霉素硫酸钙加内固定治疗跟骨病理性“鸟嘴样”骨折。记录患者手术切口、骨折愈合时间,观察骨髓炎复发情况,评价术后12个月美国足与踝关节协会踝与后足评分(American Orthopedic Foot Andankle Society,AOFAS)及渗出等并发症情况。结果:5例顺利完成手术,所有患者未出现下肢血管闭塞。5例获得随访,时间16~36个月。骨折内固定术后切口愈合时间16~26 d,所有骨折愈合,愈合时间16~27周。术后12个月AOFAS评分65~91分;其中优2例,良2例,可1例。其中1例术后5个月因烫伤导致足背部皮肤溃疡(非并发症),经治疗后痊愈;2例出现伤口渗漏并发症,经换药后伤口痊愈;所有患者未再发骨髓炎及骨折。结论:万古霉素硫酸钙联合内固定治疗糖尿病足导致跟骨骨髓炎继发跟骨病理性“鸟嘴样”骨折在控制感染的同时可促进骨折愈合,可获得较好的临床效果。

关键词：糖尿病足病理性骨折骨髓炎万古霉素骨水泥万古霉素硫酸钙

Chemical modification of barite for improving the performance of weighting materials for water-based drilling fluids

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Petroleum Science 2024年第1期21卷 551-566页

作者： Li-Li Yang Ze-Yu Liu shi-bo wang Xian-bo He Guan-Cheng Jiang Jie Zhang MOE Key Laboratory of Petroleum Engineering State Key Laboratory of Petroleum Resources and ProspectingChina University of Petroleum(Beijing)Changping DistrictBeijing102249China MOE Key CNPC Drilling Research Institute Changping DistrictBeijing102206China

With increasing drilling depth and large dosage of weighting materials,drilling fluids with high solid content are characterized by poor stability,high viscosity,large water loss,and thick mud cake,easier leading to reservoir damage and wellbore *** this paper,micronized barite(MB)was modified(mMB)by grafting with hydrophilic polymer onto the surface through the free radical polymerization to displace conventional API barite *** suspension stability of water-based drilling fluids(WBDFs)weighted with API barite:mMB=2:1 in 600 g was significantly enhanced compared with that with API barite/WBDFs,exhibiting the static sag factor within 0.54 and the whole stability index of *** viscosity and yield point reached the minimum,with a reduction of more than 40%compared with API barite only at the same *** multi-stage filling and dense accumulation of weighting materials and clays,filtration loss was decreased,mud cake quality was improved,and simultaneously it had great reservoir protection performance,and the permeability recovery rate reached 87%.In addition,it also effectively improved the lubricity of *** sticking coefficient of mud cake was reduced by 53.4%,and the friction coefficient was ***,mMB can serve as a versatile additive to control the density,rheology,filtration,and stability of WBDFs weighted with API barite,thus regulating comprehensive performance and achieving reservoir protection *** work opened up a new path for the productive drilling of extremely deep and intricate wells by providing an efficient method for managing the performance of high-density WBDFs.

关键词： Drilling fluids Weighting materials Filtration control Reservoir protection Stability property

Coexistence of hyperlipidemia and acute cerebral ischemia/reperfusion induces severe liver damage in a rat model

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World Journal of Gastroenterology 2012年第35期18卷 4934-4943页

作者： Wei-Hong Gong Wen-Xia Zheng Jun wang shi-Hui Chen bo Pang Xia-Min Hu Xiao-Lu Cao Department of Pharma-cology College of Medicine Wuhan University of Science andTechnology Wuhan 430065 Hubei Province China

AIM:To investigate the correlation of hyperlipemia(HL) and acute cerebral ischemia/reperfusion(I/R) injury on liver damage and its ***:Rats were divided into 4 groups:control,HL,I/R and HL+I/*** the induction of HL via a high-fat diet for 18 wk,middle cerebral artery occlusion was followed by 24 h of reperfusion to capture I/*** alanine transaminase(ALT) and aspartate aminotransferase(AST) were analyzed as part of liver function tests and liver damage was further assessed by histological *** apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick-end labeling(TUNEL) *** expression of genes related to apoptosis(caspase-3,bcl-2) was assayed by immunohistochemistry and Western *** tumor necrosis factor-(TNF-),interleukin-1(IL-1) and liver mitochondrial superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),malondialdehyde(MDA) and Ca 2+ levels were measured to determine inflammatory and oxidative/antioxidative status *** hydroxylase activity of the cytochrome P450 2E1(CYP2E1)-containing enzyme was measured with aniline as the substrate,and CYP2E1 expression in the liver tissue and microsome was determined by immunohistochemistry and Western blotting ***:HL alone induced by high-fat diet for 18 wk resulted in liver damage,indicated by histopathological analysis,and a considerable increase in serum ALT(25.13 ± 16.90 vs 9.56 ± 1.99,P < 0.01) and AST levels(18.01 ± 10.00 vs 11.33 ± 4.17,P < 0.05) compared with ***,HL alone induced hepatocyte apoptosis,which was determined by increased TUNEL-positive cells(4.47 ± 0.45 vs 1.5 ± 0.22,P < 0.01),higher caspase-3 and lower bcl-2 ***,compared with those in control,HL or I/R groups,massive increases of serum ALT(93.62 ± 24.00 vs 9.56 ± 1.99,25.13 ± 16.90 or 12.93 ± 6.14,P < 0.01) and AST(82.32 ± 26.92 vs 11.33 ± 4.17,18.01 ± 10.00 or 14.00 ± 6.19,P < 0.01) levels in HL+I/R group were

关键词： Hyperlipidemia High-fat diet Cerebral isch-emia/reperfusion Liver damage Hepatocyte apoptosis Cytochrome P450 2E1

基于运动目标三维轨迹重建的视频序列同步算法

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自动化学报 2017年第10期43卷 1759-1772页

作者：王雪 shi Jian-bo PARK Hyun-Soo 王庆西北工业大学计算机学院宾夕法尼亚大学工程与应用科学学院美国费城19104

提出一种利用运动目标三维轨迹重建的视频时域同步算法.待同步的视频序列由不同相机在同一场景中同时拍摄得到,对场景及相机运动不做限制性约束.假设每帧图像的相机投影矩阵已知,首先基于离散余弦变换基重建运动目标的三维轨迹.然后提... 详细信息

提出一种利用运动目标三维轨迹重建的视频时域同步算法.待同步的视频序列由不同相机在同一场景中同时拍摄得到,对场景及相机运动不做限制性约束.假设每帧图像的相机投影矩阵已知,首先基于离散余弦变换基重建运动目标的三维轨迹.然后提出一种基于轨迹基系数矩阵的秩约束,用于衡量不同序列子段间的空间时间对准程度.最后构建代价矩阵,并利用基于图的方法实现视频间的非线性时域同步.我们不依赖已知的点对应关系,不同视频中的跟踪点甚至可以对应不同的三维点,只要它们之间满足以下假设:观测序列中跟踪点对应的三维点,其空间位置可以用参考序列中所有跟踪点对应的三维点集的子集的线性组合描述,且该线性关系维持不变.与多数现有方法要求特征点跟踪持续整个图像序列不同,本文方法可以利用长短不一的图像点轨迹.本文在仿真数据和真实数据集上验证了提出方法的鲁棒性和性能.

关键词：视频同步独立运动相机运动恢复非刚性结构轨迹基秩约束

Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression

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China Ocean Engineering 2024年第2期38卷 313-325页

作者： DONG Wen-bo ZHOU Li DING shi-feng wang Ai-ming CAI Jin-yan School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of *** the Arctic,merchant ships with low ice class often navigate in channels opened up by *** in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large *** ship may get stuck if steered into ice fields off the *** this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable *** this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point *** first stage employs the image segmentation method to extract channel *** the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression *** training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel *** evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second.

关键词： ice channel ship navigation identification image segmentation corner point regression

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典型煤的近红外反射光谱特征的方向性研究

光谱学与光谱分析 2022年第3期42卷 847-858页

作者：杨恩王世博江苏建筑职业技术学院智能制造学院江苏徐州221116 中国矿业大学机电工程学院江苏徐州221116

高光谱遥感是煤矿区探测的有效方法,对于煤炭资源调查、矿区环境监测等具有重要意义,其中煤、矸石、植被、水体等被遥测物各个方向的反射光谱特征是煤矿高光谱遥感的基础,为此有必要针对典型煤的方向反射光谱特征进行研究。从我国不同... 详细信息

高光谱遥感是煤矿区探测的有效方法,对于煤炭资源调查、矿区环境监测等具有重要意义,其中煤、矸石、植被、水体等被遥测物各个方向的反射光谱特征是煤矿高光谱遥感的基础,为此有必要针对典型煤的方向反射光谱特征进行研究。从我国不同矿区收集了无烟煤、烟煤、褐煤三大类煤中的4种典型煤样,4种煤样按煤阶由高到低顺序包括无烟煤一号、贫煤、气煤、褐煤二号,在实验室利用方向反射测量球坐标实验装置测定了每种煤样半球空间各反射方向的近红外波段(1000~2500 nm)反射光谱曲线。通过对反射光谱曲线波形分析,发现同一种煤不同反射方向的近红外反射光谱波形基本相似,但在整体反射率大小和局部波形特征上具有差异性,光谱曲线整体反射率越大,吸收谷越明显。随反射角增大,4种煤在前向反射方向(180°探测方位角)反射光谱曲线均整体上升,在后向反射方向(0°探测方位角)反射光谱曲线高度变化相对较小。在每种煤半球空间各反射方向的反射光谱曲线中,选取了1400,1700,1900,2200和2300 nm 5个特征波长,通过分析此5个特征波长处的反射率空间分布极坐标云图,发现4种煤在5个特征波长点处均具有一定的双向反射特征,均表现出较明显的前向反射热点特征和相对较弱的后向反射热点特征,无烟煤一号后向反射热点特征比贫煤、气煤、褐煤二号更明显,贫煤、气煤、褐煤二号随煤阶降低后向反射热点特征逐渐增强。每种煤前、后向反射方向的反射光谱中,通过对5个特征波长处反射率与反射角进行相关性分析,发现前向反射特征波长反射率与反射角近似呈线性函数关系,后向反射特征波长反射率与反射角近似呈高斯函数关系,且高斯函数拟合曲线波峰随煤阶降低向较大反射角度移动。该研究为矿区煤炭高光谱遥感最优探测几何的选择提供了依据,也为矿区煤炭资源精准探测提供了参考。

关键词：煤矿区高光谱遥感近红外方向反射特征波长点