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Role of nickel on vanadium poisoned FCC catalyst: A study of physiochemical properties

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Journal of Energy Chemistry 2016年第4期25卷 667-676页

作者： U.J.Etim b.xu P.bai Rooh Ullah F.Subhan Z.Yan State Key Laboratory of Heavy Oil Processing Petro China Key Laboratory of CatalysisChina University of PetroleumQingdao Department of Chemistry Abdul Wali Khan University Mardan

Active sites of Fluid catalytic cracking (FCC) catalyst are poisoned during operation in the FCC reactor due to causes including feedstock contaminant metals deposition. This leads to activity, selectivity and increasing coking problems, thereby raising concern to the refiner. This work investigated effect of nickel coexisting with vanadium in the FCC feedstock on the standard FCC catalyst during cracking process, in which destruction of active sites occurs as a result of the metals deposition. Laboratory simulated equilibrium catalysts (E-cats) were studied by XRD, FTIR spectroscopy, N-2 adsorption, solid state MAS-NMR, SEM and H-2-TPR. Results revealed that vanadium, above a certain concentration in the catalyst, under hydrothermal conditions, is highly detrimental to the catalyst's structure and activity. Conversely, nickel hardly affects the catalyst structure, but its co-presence in the catalyst reduces destructive effects of vanadium. The mechanism of nickel inhibition of vanadium poisoning of the catalyst is discussed. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier b.V. and Science Press. All rights reserved.

关键词： FCC catalyst Contaminant metals Activity Physiochemical properties Mechanism

Micro injection of metallic glasses parts under ultrasonic vibration

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Journal of Materials Science & Technology 2017年第7期33卷 703-707页

作者： X.Liang J.Ma X.Y.Wu b.xu F.Gong J.G.Lei T.J.Peng R.Cheng Guangdong Provincial Key Laboratory ofMicro/Nano Optomechatronics Engineering College of Mechatronics and Control and Engineering Shenzhen University Shenzhen 518060 China Shenzhen ESUN Exhibition Company Limited Shenzhen 518048. China

This work investigates the evolution of structure and mechanical performance of metallic glasses（MGs）under a proposed rapid forming approach. Through the unique ultrasonic-assisted micro injection method, micro MGs parts with fine dimensional accuracy were successfully fabricated. The temperature during the micro injection is higher than the glass transition temperature and lower than the crystallization temperature. Differential scanning calorimeter curve and X-ray diffraction pattern show that the MGs micro parts keep the amorphous nature after the ultrasonic-assisted micro injection. Our results propose a novel route for the fast forming of MGs and have promising applications in the rapid fabrication of micro scale products and devices.

关键词： Metallic glasses Micro injection Ultrasonic vibration

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PMMA／石墨导电复合材料的制备与表征

化学研究与应用 2008年第7期20卷 848-853页

作者：黄光平洪若瑜 b.xu 李洪钟尉东光苏州大学化学化工学院江苏省有机合成重点实验室苏州215123 中国科学院过程工程研究所多相反应国家重点实验室北京100080 Nanotec Inc．(Suzhou) 苏州业园区215123 Center for Nanoscale Sys. School of Eng. ＆ Appl. Sci. Harvard Univ. 11 Oxford St. Cambridge MA 02139 USA

以可膨化石墨为原料,高温处理得到膨化石墨,再经过超声处理,得到纳米薄片石墨。将得到的纳米薄片石墨与甲基丙烯酸甲酯单体在超声作用下预聚,灌模,得到块状的聚甲基丙烯酸甲酯(PMMA)/石墨复合材料。用扫描电子显微镜(SEM)、透射电子显微... 详细信息

以可膨化石墨为原料,高温处理得到膨化石墨,再经过超声处理,得到纳米薄片石墨。将得到的纳米薄片石墨与甲基丙烯酸甲酯单体在超声作用下预聚,灌模,得到块状的聚甲基丙烯酸甲酯(PMMA)/石墨复合材料。用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、选区电子衍射SAD、红外、热重等分析仪器表征了纳米石墨薄片及PMMA/石墨复合材料。测试了复合材料的力学、电学性能,发现在室温下该复合材料的渗滤阀值为1.3%(wt),且保证石墨含量在1.4%(wt)时,即可保证复合材料具有良好的电学和力学性能。

关键词：石墨插层反应原位聚合聚甲基丙烯酸甲酯

在纤维图像处理中对多纤维横截面自动分离的一种新的分割算法

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国外纺织技术 2000年第9期 36-41页

作者： b.xu 纪峰吴兆平冯毅力李汝勤

在纤维图像处理中对多纤维横截面自动分离的一种新的分割算法

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国外纺织技术（纺织针织服装化纤染整） 2000年第9期 36-41页

作者： b.xu 纪峰吴兆平冯毅力李汝勤

Ag/Pb(Zr0.53Ti0.47)O3/Yba2Cu3O7-x三端器件构造和性能的研究

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低温物理学报 1999年第1期21卷 60-64页

作者：刘保亭,Ｙｕ．Ｋｉｓｌｉｎｓｋｉi,郝昭,陈莺飞,许波,陈红,吴非,赵柏儒中国科学院物理研究所国家超导实验室

应用脉冲激光沉积法和光刻技术我们成功地制作Ａｇ／Ｐｂ（Ｚｒ０．５３Ｔｉ０．４７）Ｏ３／ＹＢａ２Ｃｕ３Ｏ７－ｘ（ＰＺＴ／ＹＢＣＯ）三端器件．为了降低矫顽场，应用变形相界（ｘ≈０．５３）的５５０纳米厚的ＰＺＴ作为门电极，... 详细信息

应用脉冲激光沉积法和光刻技术我们成功地制作Ａｇ／Ｐｂ（Ｚｒ０．５３Ｔｉ０．４７）Ｏ３／ＹＢａ２Ｃｕ３Ｏ７－ｘ（ＰＺＴ／ＹＢＣＯ）三端器件．为了降低矫顽场，应用变形相界（ｘ≈０．５３）的５５０纳米厚的ＰＺＴ作为门电极，通过优化沉积条件和门电极面积小型化（６×１０－６ｃｍ２），在６４Ｋ下三端器件门电极显示了极好的电性能，低的矫顽场（～３７ｋＶ／ｃｍ）、大的饱和极化强度（６０μＣ／ｃｍ２）、剩余极化强度（４１μＣ／ｃｍ２）以及击穿电压～３×１０５Ｖ／ｃｍ．对于我们的场效应器件，在±９Ｖ的情况下沟道电阻被调制～３％．

关键词：击穿电压场效应器件 O3/Yba2Cu3O Ti Zr Ag/Pb 矫顽场矫顽力正常态

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多参数MRI评估慢性肾病和肾纤维化的价值

国际医学放射学杂志 2023年第5期 622-622页

作者： C.Hua L.Qiu L.Zhou Y.Zhuang T.Cai b.xu 许振华

摘要目的确定评估慢性肾脏病（CKD）和肾间质纤维化（IF）的最佳MRI参数。方法前瞻性纳入43例CKD病人和20例正常对照组。CKD组根据病理检查结果分为轻度和

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双标记PIb-PET和双示踪剂PET在阿尔茨海默病诊断的比较

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国际医学放射学杂志 2015年第1期 86-86页

作者： L.Fu L.Liu J.Zhang b.xu Y.Fan J.Tian Department of Nuclear Medicine General Hospital of the Chinese People’s Liberation Army

目的确定从早期11C-PIb(灌注PIb,11C-p PIb)影像捕获灌注信息最佳时间窗;比较18F-FDG PET和双标记11C-PIb PET[11C-p PIb和淀粉样蛋白PIb(11C-a PIb)]在阿尔

关键词：阿尔茨海默病 FDG 双标记 PIb-PET PET 示踪剂示踪物

The pivotal role of microglia in injury and the prognosis of subarachnoid hemorrhage

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Neural Regeneration Research 2025年第7期20卷 1829-1848页

作者： Wenjing Ning Shi Lv Qian Wang Yuzhen xu Department of Rehabilitation The Second Affiliated Hospital of Shandong First Medical UniversityTaianShandong ProvinceChina Department of Central Laboratory The Affiliated Taian City Central Hospital of Qingdao UniversityTaianShandong ProvinceChina

Subarachnoid hemorrhage leads to a series of pathological changes,including vascular spasm,cellular apoptosis,blood–brain barrier damage,cerebral edema,and white matter ***,which are the key immune cells in the central nervous system,maintain homeostasis in the neural environment,support neurons,mediate apoptosis,participate in immune regulation,and have neuroprotective *** evidence has shown that microglia play a pivotal role in the pathogenesis of subarachnoid hemorrhage and affect the process of injury and the prognosis of subarachnoid ***,microglia play certain neuroprotective roles in the recovery phase of subarachnoid *** approaches aimed at modulating microglia function are believed to attenuate subarachnoid hemorrhage *** provides new targets and ideas for the treatment of subarachnoid ***,an in-depth and comprehensive summary of the role of microglia after subarachnoid hemorrhage is still *** review describes the activation of microglia after subarachnoid hemorrhage and their roles in the pathological processes of vasospasm,neuroinflammation,neuronal apoptosis,blood–brain barrier disruption,cerebral edema,and cerebral white matter *** also discusses the neuroprotective roles of microglia during recovery from subarachnoid hemorrhage and therapeutic advances aimed at modulating microglial function after subarachnoid ***,microglia in subarachnoid hemorrhage are targeted with TLR inhibitors,nuclear factor-κb and STAT3 pathway inhibitors,glycine/tyrosine kinases,NLRP3 signaling pathway inhibitors,Gasdermin D inhibitors,vincristine receptorαreceptor agonists,ferroptosis inhibitors,genetic modification techniques,stem cell therapies,and traditional Chinese ***,most of these are still being evaluated at the laboratory *** clinical studies and data on subarachnoid hemorrhage are required to improve the treatment of subarachnoid hemor

关键词： apoptosis blood–brain barrier brain edema microglia neuroinflammation neuron neuroprotection subarachnoid hemorrhage vasoconstriction white matter injury