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Adhesion and friction performance of DLC/rubber:The influence of plasma pretreatment

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Friction 2021年第3期9卷 627-641页

作者： changning bai Zhenbin GONG Lulu AN Li QIANG Junyan ZHANG Georgy YUSHKOV Alexey NIKOLAEV Maxim SHANDRIKOV Bin ZHANG Key Laboratory of Science and Technology on Wear and Protection of Materials Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China High Current Electronics Institute Russian Academy of SciencesTomsk 634055Russia

Diamond-like carbon(DLC)films are deposited on rubber surfaces to protect the rubber components,and surface pretreatment of the rubber substrates prior to the film deposition can improve the adhesion between the DLC films and the ***,the principal purpose of this work concentrates on determining the effects of argon(Ar),oxygen(O_(2)),nitrogen(N_(2)),and hydrogen(H_(2))plasma pretreatments on the adhesion and friction performance of the DLC films deposited on rubber(DLC/rubber).The results indicated that the Ar plasma pretreatment promoted the formation of a compact layer on the rubber *** contrast,massive fillers were exposed on the rubber surface after oxygen or nitrogen plasma ***,the typical micrometer-scale patches divided by random cracks were observed on the surface of DLC/rubber,except for the sample pretreated with oxygen *** adhesion of DLC/rubber was found to strengthen with the removal of weak boundary layers and the generation of free radicals on the rubber surface after plasma *** tribo-tests revealed that DLC/rubber with O_(2),N_(2),and H_(2) plasma pretreatments cannot achieve optimal friction ***,DLC/rubber with Ar plasma pretreatment exhibited a low and stable friction coefficient of 0.19 and superior wear resistance,which was correlated to the high adhesion,good load-bearing of the rubber surface,and the approximate sine function of the surface profile of the DLC film.

关键词： diamond-like carbon(DLC)films rubber plasma pretreatment adhesion friction

六方氮化硼气凝胶的制备及其导热和吸附性能的研究进展

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中国科学：化学 2020年第8期50卷 891-899页

作者：赵召屈孟男白常宁安璐璐于元烈中国科学院材料磨损与防护重点实验室中国科学院兰州化学物理研究所兰州730000 西安科技大学化学与化工学院西安710054

六方氮化硼(h-BN)是一种类石墨结构的材料,因其具有优异的机械强度、较宽的带隙、较强的高温抗氧化性、优异的电绝缘性和突出的导热性而吸引了无数科研人员的青睐.但是,纳米尺度的h-BN分散性较差且极易团聚,影响其广泛应用.h-BN基气凝... 详细信息

六方氮化硼(h-BN)是一种类石墨结构的材料,因其具有优异的机械强度、较宽的带隙、较强的高温抗氧化性、优异的电绝缘性和突出的导热性而吸引了无数科研人员的青睐.但是,纳米尺度的h-BN分散性较差且极易团聚,影响其广泛应用.h-BN基气凝胶具有稳定的三维网络结构,低密度,可以作为高导热性超轻材料或导热聚合物添加剂.此外,h-BN基气凝胶具有可调的开放孔隙结构,高比表面积和可压缩性,可以作为理想的吸附材料,用于吸附空气或水中的有毒气体、重金属离子或者有机污染物等.本文结合国内外研究进展,归纳了h-BN基气凝胶的制备方法,如冷冻干燥法、化学气相沉积法、辅助模板法和复合交联法等,并对其在导热和吸附方面的应用作了详细的介绍.

关键词：六方氮化硼气凝胶导热吸附性能

空气等离子预处理改善橡胶表面碳膜结合强度和耐磨性研究

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真空与低温 2019年第5期25卷 324-330页

作者：白常宁强力唐宏亮张斌张俊彦中国科学院兰州化学物理研究所固体润滑国家重点实验室兰州730000 中国科学院大学材料与光电研究中心北京100049 上海航天控制技术研究所上海201109

为增强橡胶在动密封环境服役的耐磨性,采用等离子体增强化学气相沉积技术在丁腈橡胶表面制备非晶碳膜。利用高分辨透射电子显微镜(HRTEM)、显微共焦拉曼光谱仪、扫描电子显微镜(SEM)、傅里叶变换红外光谱仪(FTIR)、划痕测试仪、球盘摩... 详细信息

为增强橡胶在动密封环境服役的耐磨性,采用等离子体增强化学气相沉积技术在丁腈橡胶表面制备非晶碳膜。利用高分辨透射电子显微镜(HRTEM)、显微共焦拉曼光谱仪、扫描电子显微镜(SEM)、傅里叶变换红外光谱仪(FTIR)、划痕测试仪、球盘摩擦磨损试验机等表征空气等离子体预处理偏压对薄膜结构、膜基结合力和摩擦学性能的影响。结果表明:随空气等离子体预处理偏压升高,薄膜趋于石墨化。预处理偏压为-900V时,薄膜/橡胶呈现最优的膜基结合力(46N)和摩擦性能(平均摩擦系数0.24),比原始橡胶的摩擦系数降低了70%,摩擦曲线稳定、耐磨性较强。说明空气等离子体预处理能够提高膜基结合强度,有效增强橡胶的耐磨性。

关键词：丁腈橡胶空气等离子体预处理非晶碳膜膜基结合力摩擦性能

丁腈橡胶磨损失效机制及其表面碳薄膜改性技术

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飞控与探测 2022年第1期5卷 92-102页

作者：白常宁余三成刘洪宇唐宏亮张俊彦中国科学院兰州化学物理研究所兰州730000 上海航天控制技术研究所上海201109 上海伺服系统工程技术研究中心上海201109

针对航天伺服机构密封件因磨损失效导致的泄漏难题,分析了大气及氮气环境下丁腈橡胶磨损失效机制。在此基础上,提出了丁晴橡胶表面硬质类金刚石碳薄膜(DLC)改性技术,并分析了改性后丁腈橡胶密封实件的综合性能。结果表明:大气环境、恒... 详细信息

针对航天伺服机构密封件因磨损失效导致的泄漏难题,分析了大气及氮气环境下丁腈橡胶磨损失效机制。在此基础上,提出了丁晴橡胶表面硬质类金刚石碳薄膜(DLC)改性技术,并分析了改性后丁腈橡胶密封实件的综合性能。结果表明:大气环境、恒定载荷(小载低速)条件下,丁腈橡胶主要以分层剥落方式磨损(疲劳磨损)。随着摩擦速度(或载荷)的增大,其磨损失效主要表现为黏着磨损。对于氮气环境,氮气能够有效避免摩擦界面氧化作用,即降低了黏着磨损效应;此外,改性后橡胶密封实件在机械性能、质密性和密封性等方面较原始密封件未发生明显变化。经过4000次台架磨合试验后,油端密封圈表面光洁,无异常磨损;气端密封圈表面存在轻微磨损,能够满足使用要求。

关键词：丁腈橡胶磨损失效机制类金刚石碳薄膜改性密封实件综合性能

Development of a potential PET probe for HDAC6 imaging in Alzheimer's disease

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Acta Pharmaceutica Sinica B 2022年第10期12卷 3891-3904页

作者： Ping bai Prasenjit Mondal Frederick A.Bagdasarian Nisha Rani Yan Liu Ashley Gomm Darcy R.Tocci Se Hoon Choi Hsiao-Ying Wey Rudolph E.Tanzi Can Zhang changning Wang Athinoula A.Martinos Center for Biomedical Imaging Department of RadiologyMassachusetts General HospitalHarvard Medical SchoolCharlestownMA 02129USA Genetics and Aging Research Unit McCance Center for Brain HealthMassGeneral Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolCharlestownMA 02129USA

Although the epigenetic regulatory protein histone deacetylase 6(HDAC6)has been recently implicated in the etiology of Alzheimer’s disease(AD),little is known about the role of HDAC6 in the etiopathogenesis of AD and whether HDAC6 can be a potential therapeutic target for ***,we performed positron emission tomography(PET)imaging in combination with histopathological analysis to better understand the underlying pathomechanisms of HDAC6 in *** first developed[^(18)F]PB118 which was demonstrated as a valid HDAC6 radioligand with excellent brain penetration and high specificity to *** studies of[^(18)F]PB118 in 5xFAD mice showed significantly increased radioactivity in the brain compared to WT animals,with more pronounced changes identified in the cortex and *** translatability of this radiotracer for AD in a potential human use was supported by additional studies,including similar uptake profiles in non-human primates,an increase of HDAC6 in ADrelated human postmortem hippocampal tissues by Western blotting protein analysis,and our ex vivo histopathological analysis of HDAC6 in postmortem brain tissues of our ***,our findings show that HDAC6 may lead to AD by mechanisms that tend to affect brain regions particularly susceptible to AD through an association with amyloid pathology.

关键词： HDAC6 Alzheimer’s disease Radiotracer PET imaging Epigenetic

Novel radioligands for imaging sigma-1 receptor in brain using positron emission tomography(PET)

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Acta Pharmaceutica Sinica B 2019年第6期9卷 1204-1215页

作者： Yu Lan Ping bai Zude Chen Ramesh Neelamegam Michael SPlaczek Hao Wang Stephanie AFiedler Jing Yang Gengyang Yuan Xiying Qu Hayden RSchmidt Jinchun Song Marc DNormandin Chongzhao Ran changning Wang Athinoula A.Martinos Center for Biomedical Imaging Department of RadiologyMassachusetts General HospitalHarvard Medical SchoolCharlestownMA 02129USA Gordon Center for Medical Imaging Department of RadiologyMassachusetts General HospitalHarvard Medical SchoolCharlestownMA 02129USA Department of Biological Chemistry and Molecular Pharmacology Harvard Medical SchoolBostonMA 02129USA Department of Pharmacy Renmin Hospital of Wuhan UniversityWuhan 430060China

The sigma-1 receptor(σ1R)is a unique intracellular protein.σ1R plays a major role in various pathological conditions in the central nervous system(CNS),implicated in several neuropsychiatric *** ofσ1R in the brain using positron emission tomography(PET)could serve as a noninvasively tool for enhancing the understanding of the disease’s ***,σ1R PET tracers can be used for target validation and quantification in ***,we describe the radiosynthesis,in vivo PET/CT imaging of novelσ1R11C-labeled radioligands based on 6-hydroxypyridazinone,[11C]HCC0923 and[11C]*** radioligands have high affinities toσ1R,with good *** mice PET/CT imaging,both radioligands showed appropriate kinetics and ***,the specific interactions of two radioligands were reduced by compounds 13 and 15(self-blocking).Ofthe two,[11C]HCC0929 was further investigated in positive ligands blocking studies,using classicσ1R agonist SA 4503 andσ1R antagonist PD ***σ1R ligands could extensively decreased the uptake of[11C]HCC0929 in mice ***,the biodistribution of major brain regions and organs of mice were determined in *** studies demonstrated that two radioligands,especially[11C]HCC0929,possessed ideal imaging properties and might be valuable tools for non-invasive quantification ofσ1R in brain.

关键词： σ1R PET Brain imaging 6-Hydroxypyridazinone 11C-labeled radioligand

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基于矩阵PBM的煤粉超细粉碎过程研究

煤炭学报 2019年第6期44卷 1906-1914页

作者：楚长青赵冰龙白雪涛吴昌宁翁力李国涛刘科南方科技大学前沿与交叉科学研究院广东深圳518055 南方科技大学创新创业学院广东深圳518055 南方科技大学理学院广东深圳518055

建立基于研磨过程机理的煤粉超细研磨动力学模型可以预测超细磨出料的粒度分布和指导优化磨机的研磨效率,降低研磨能耗,对制备低灰分的超净煤具有非常重要的作用。通过田口(Taguchi)正交实验设计,使用实验室1.5 L立式搅拌磨机考察了不... 详细信息

建立基于研磨过程机理的煤粉超细研磨动力学模型可以预测超细磨出料的粒度分布和指导优化磨机的研磨效率,降低研磨能耗,对制备低灰分的超净煤具有非常重要的作用。通过田口(Taguchi)正交实验设计,使用实验室1.5 L立式搅拌磨机考察了不同煤的物性参数、磨介尺寸和煤粉比处理量对于超细研磨的影响,将基于研磨过程特征的动力学模型矩阵粒群平衡模型(Matrix Population Balance Model,M-PBM)用于煤粉的搅拌磨机超细研磨出料的粒度预测,并结合Rosin-Rammler粒度分布模型,精确地预测出料产品在任意筛下累积含量对应的颗粒粒度。通过极差分析,探讨了煤的灰分、磨介尺寸和煤粉比处理量对于超细研磨能耗和比通量的影响大小,基于对煤粉超细研磨过程中煤-灰解离过程的分析并结合Tomoyoshi的比表面积能耗公式,探讨了煤的灰分与能耗的关系,并进一步建立了煤的灰分、磨介尺寸和煤粉比处理量与磨机研磨比通量和能耗的关系式,研究发现搅拌球磨机湿法超细研磨的粒度变化规律符合一阶线性动力学假设,在定搅拌转轴转速和所考查的研磨粒度变化范围内,煤的灰分对搅拌磨机的比通量和能耗的影响是最大的,建立的研磨能耗和比通量关系式表明在10μm(p50)以下的超细粉磨粒度范围内,煤的研磨能耗随着灰分的提高、磨介尺寸的减小(磨介尺寸在0.3~1.8 mm)和比处理量的增大而减小,而比通量随着灰分的提高、磨介尺寸的减小和比处理量的增大而增大。

关键词：超细磨 PBM模型超净煤粒度分布搅拌磨机

Value of shear wave elastography with maximal elasticity in differentiating benign and malignant solid focal liver lesions

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World Journal of Gastroenterology 2020年第46期26卷 7416-7424页

作者： Hui-Ping Zhang Ji-Ying Gu Min bai Fan Li Yu-Qing Zhou Lian-Fang Du Department of Ultrasound Shanghai Changning Maternity and Infant Health HospitalEast China Normal UniversityShanghai 200050China Department of Ultrasound Shanghai Fourth People’s HospitalShanghai Tongji University School of MedicineShanghai 200434China Department of Ultrasound Shanghai General HospitalShanghai Jiaotong University School of MedicineShanghai 200080China

BACKGROUND It is important to differentiate benign and malignant focal liver lesions(FLLs)*** the wide use and acceptance of shear wave elastography(SWE),its value for assessing the elasticity of FLLs and differentiating benign and malignant FLLs is still *** studies of SWE for FLLs used mean elasticity as the parameter to reflect the stiffness of *** the inhomogeneity of tumor stiffness,maximal elasticity(Emax)might be the suitable parameter to reflect the stiffness of FLLs and to differentiate malignant FLLs from benign *** To explore the value of SWE with Emax in differential diagnosis of solid *** We included 104 solid FLLs in 95 patients and 50 healthy *** the subjects were examined using conventional ultrasound(US)and virtual touch tissue quantification(VTQ)imaging.A diagnosis of benign or malignant FLL was made using conventional *** VTQ values were acquired after 10 consecutive measurements for each FLL and each normal liver,and the largest value was recorded as *** There were 56 cases of malignant FLLs and 48 cases of benign FLLs in this *** of malignant FLLs(3.29±0.88 m/s)was significantly higher than that of benign FLLs(1.30±0.46 m/s,P<0.01)and that of livers in healthy volunteers(1.15±0.17 m/s,P<0.01).The cut-off point of Emax was 1.945,and the area under the curve was *** sensitivity and specificity of Emax were 92.9%and 91.7%,respectively,higher(but not significantly)than those of conventional US(80.4%for sensitivity and 81.3%for specificity).Combined diagnosis of conventional US and Emax using parallel testing improved the sensitivity to 100%with specificity of 75%.CONCLUSION SWE is a convenient and easy method to obtain accurate stiffness information of solid *** is useful for differential diagnosis of FLLs,especially in combination with conventional US.

关键词： Focal hepatic lesions Shear wave elastography Conventional ultrasound Maximal elasticity

不同LED光源对百合组培苗小子球繁育的影响

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北方园艺 2019年第24期 68-73页

作者：王玉英白晓云段正瑞叶长宁赵聃李枝林云南农业大学园林园艺学院

以百合‘索邦’品种组培苗为试材,白色荧光灯为对照,研究了7种不同LED光源对组培苗小子球繁育的影响。结果表明:单色蓝光(B)处理对植株生长效果最好,株高、根长和叶片数达到最高值,分别为5.67 cm、2.28 cm和3.10片;红蓝绿复合光(RBG)对... 详细信息

以百合‘索邦’品种组培苗为试材,白色荧光灯为对照,研究了7种不同LED光源对组培苗小子球繁育的影响。结果表明:单色蓝光(B)处理对植株生长效果最好,株高、根长和叶片数达到最高值,分别为5.67 cm、2.28 cm和3.10片;红蓝绿复合光(RBG)对小子球增殖效果最好,增殖率为对照的2倍;红蓝复合光(2RB)处理后鲜质量达到最大值0.207 g,与其它处理差异显著;单色红光(R)处理下,干质量达到最大值0.038 g,与其它处理差异显著;红蓝绿复合光(RBG)处理下,叶绿素a含量和总叶绿素含量最高分别为0.9536 mg·g-1和1.1965 mg·g-1;白光(W)处理下可溶性糖含量和可溶性蛋白质含量达到最大值分别为1.3987%和1.485 mg·g-1,与红蓝绿复合光(RBG)处理下差异不显著,均与对照(CK)差异显著。综合比较各项指标,红蓝绿复合光(RBG)可作为百合‘索邦’小子球繁育的理想光源。

关键词： LED光源百合‘索邦’ 组培苗小子球繁育