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Improved activity of Ni-Mo/SiO_(2) bimetallic catalyst synthesized via sol-gel method for methylcyclohexane cracking

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Petroleum Science 2021年第5期18卷 1530-1542页

作者： Jun Zhang Ting chen Yi Jiao Mei cheng Lin-Lin wang Jian-Li wang xiang-Yuan Li yao-Qiang chen School of Chemical Engineering Sichuan UniversityChengdu610064SichuanChina Institute of New Energy and Low-Carbon Technology Sichuan UniversityChengdu610064SichuanChina College of Chemistry Sichuan UniversityChengdu610064SichuanChina

To improve the cracking behavior of hydrocarbon,Ni-Mo/SiO_(2) bimetallic catalysts were synthesized by different preparation methods(sol-gel,co-impregnation and single-impregnation) and added the additives(citric acid,polyethylene glycol and cetyltrimethylammonium bromide) based on the most suitable method *** cracking reaction of methylcyclohexane under supercritical conditions was performed as the probe reaction to estimate the catalytic performance,and the properties of Ni-Mo/SiO_(2) catalyst were characterized by N_(2) absorption-desorption,XRD,XPS,H_(2)-TPR,NH_(3)-TPD,in-situ IR of NH_(3) desorption,HRTEM and STEM-mapping so as to study the structure-activity *** catalyst synthesized via sol-gel method showed the best conversion and heat sink,being 81.8% and 3.81 MJ/kg,which was closely related to strong mutual effect between active components and SiO_(2) as well as strong acid ***,the introduction of additives by sol-gel method has an affirmative influence on properties of Ni-Mo/SiO_(2) catalysts,being that the acidity(more L and B acid sites) was modulated and organic groups interact with metal to suppress the aggregation of metal species(Ni and Mo),thereby enhancing the catalytic *** 750℃,the conversion(89.3%) as well as heat sink(3.99 MJ/kg) of MCH cracking obtained an optimum over Ni-Mo/SiO_(2) catalyst with addition of citric acid.

关键词： Ni dispersion Ni-Mo/SiO_(2) Catalytic cracking Citric acid Sol-gel method Acidity modulation

Corrosion resistance behavior of gradient microstructure induced by punching deformation and recovery treatment on cupronickel alloy surface

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Rare Metals 2017年第12期36卷 971-976页

作者： xiang-Yang Mao Hao chen Hong-Yan Yang yao yao Hong-xing wang Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology School of Materials EngineeringNanjing Institute of Technology Nanjing 211167 China

In this study, the gradient grain induced by punching deformation and recovery treatment on a cupronickel alloy surface sample were investigated, and their effects on corrosion resistance were measured by atom force microscopy(AFM), X-ray diffraction(XRD),electrochemical measurement, electron work function(EWF), and contact electrical resistance(CER). The cupronickel alloy surface experienced punching deformation for 60 min and recovery at 300 ℃ for 1 h to produce gradient surface. The grain size measured by XRD is bigger than that measured by AFM, due to X-ray intensity of95 % produced at the depth of 12-20 μm for the crystal planes of(111),(200), and(220). The gradient grain surface, compared to the original surface, shows a 13.7-fold decrease in passivation current density(i), and corrosion potential(Ec) increases by approximately 9.8 %. These results are attributable to the increase in EWF and formation of passivation film with better adhesion and compactness after treatment.

关键词： Gradient grain Corrosion resistance Electron work function Punching deformation

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郫县豆瓣感官轮及定量描述剖面建立

食品科学 2025年第3期46卷 179-186页

作者：陈厚银钟葵云振宇史波林汪厚银张瑶张丽涵何晓宁项雅科赵镭西南交通大学生命科学与工程学院四川成都610031 中国标准化研究院农业食品标准化研究所国家市场监督管理总局重点实验室(食品感官分析)北京102200

为探究中国地理标志产品郫县豆瓣的感官特性,通过感官评价小组构建郫县豆瓣的感官轮及定量描述剖面。采用中心点剖面法结合几何平均值对市面上21款豆瓣产品进行感官描述词开发,构建包括外观、基本味、香气、风味和质地5个维度共计53个... 详细信息

为探究中国地理标志产品郫县豆瓣的感官特性,通过感官评价小组构建郫县豆瓣的感官轮及定量描述剖面。采用中心点剖面法结合几何平均值对市面上21款豆瓣产品进行感官描述词开发,构建包括外观、基本味、香气、风味和质地5个维度共计53个感官描述词。进一步结合多元统计方法复选出23个感官描述词并建立相应的强度参比样,开展不同种类和等级郫县豆瓣感官品质的定量描述评价。结果表明,郫县传统豆瓣酱香、辣香更强、质地偏黏,可见性(蚕豆瓣)、硬度更大。相比传统豆瓣,郫县红油豆瓣颜色偏红褐色,具有更强的油香、香料香、湿润性和油味等特性。随等级增加,郫县豆瓣的酱香、豆豉味等特征更突出,滋味更加醇厚。本研究可为郫县豆瓣的感官品质评价、产品质量控制及改进提供基础数据和评价方法参考。

关键词：郫县豆瓣感官描述词多元分析方法感官轮定量描述剖面

Sonochemical Degradation of Polychlorinated Biphenyls in Aqueous Solution

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Chinese Chemical Letters 2003年第2期14卷 205-208页

作者： xi Kui wang Guan Hong chen Zhong Yan yao College of Chemistry and Environmental Science University of JinanJinan 250022

Polychlorinated biphenyl (PCB) is a kind of persistent and dangerous environmental pollutants. This paper presented the research result of sonochemical degradation of 2-chloro- biphenyl (2-CBP), 4-chlorobiphenyl (4-CBP) and 4,4-dichlorobiphenyl (4,4-CBP)in water. The ultrasonic degradation kinetics of 2-CBP, 4-CBP and 4,4-CBP in water were found to be first-order and the degradation rate coefficients are 3.69?0-2, 3.19?0-2 and 2.06?0-2 at 25?C for 2-CBP, 4-CBP and 4,4-CBP respectively. The influence of initial concentrations, reaction temperature on the ultrasonic decomposition of 2-CBP were also investigated.

关键词： Polychlorinated biphenyl degradation sonochemistry 2-chlorobiphenyl.

基于扩展Kalman滤波算法的半球谐振子特征参数辨识方法

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光学与光电技术 2025年第1期23卷 79-85页

作者：高心想王晨晟张熙邹康华中光电技术研究所-武汉光电国家研究中心湖北武汉430223

针对如何有效辨识半球谐振子特征参数的问题,提出了一种基于扩展Kalman滤波算法的辨识方法,来辨识谐振子四个特征参数:刚度各向异性Δ_(ω)、刚度失准角θ_(ω)、阻尼各向异性Δ(1/τ)和阻尼失准角θ_(τ)。根据非理想半球谐振子的幅值... 详细信息

针对如何有效辨识半球谐振子特征参数的问题,提出了一种基于扩展Kalman滤波算法的辨识方法,来辨识谐振子四个特征参数:刚度各向异性Δ_(ω)、刚度失准角θ_(ω)、阻尼各向异性Δ(1/τ)和阻尼失准角θ_(τ)。根据非理想半球谐振子的幅值控制方程和正交控制方程,构建了基于扩展Kalman滤波算法的参数辨识方程,并搭建了半球谐振陀螺仿真模型,从而验证了提出方法的有效性。仿真结果表明,所有特征参数均在15 s内收敛至设定的期望值。所提出的方法能够有效辨识出半球谐振子的特征参数,可为半球谐振陀螺的误差校准、补偿以及系统精度提升提供有利指导。

关键词：谐振陀螺半球谐振子特征参数扩展Kalman滤波半球谐振陀螺

基于LKB1/AMPK/mTOR通路调节自噬探讨固本健脑液对阿尔茨海默病的作用机制

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中国中药杂志 2025年第2期50卷 293-300页

作者：张婧凡龙清华曾楚华陈益敏谢喆尧蔡元钦王曦湖北民族大学医学部湖北恩施445000 云南中医药大学基础医学院云南昆明650500 湖北民族大学风湿性疾病发生与干预湖北省重点实验室湖北恩施445000 湖北民族大学附属民大医院湖北恩施445000

基于肝激酶B1(liver kinase B1,LKB1)/腺苷酸活化蛋白激酶(adenosine monophosphate-activated protein kinase,AMPK)/哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)通路调节自噬探讨固本健脑液对阿尔茨海默病(Alzheimer's disease,AD)的作用机制。雄性SD大鼠随机分为空白组、模型组、固本健脑液低剂量组、固本健脑液高剂量组和雷帕霉素组,每组10只。除空白组外,其余组大鼠均双侧海马注射β-淀粉样蛋白(β-amyloid,Aβ)1-42建立AD模型。固本健脑液低剂量组(6.21 g·kg^(-1))、固本健脑液高剂量组(12.42 g·kg^(-1))、雷帕霉素组(1 mg·kg^(-1))给予相应药物灌胃,空白组、模型组给予等体积生理盐水灌胃,持续4周。Morris水迷宫检测各组大鼠学习记忆能力;苏木精-伊红(hematoxylin-eosin,HE)染色、尼氏染色观察大鼠海马CA1区神经元及尼氏体形态数量变化;免疫组化检测大鼠海马CA1区Aβ阳性细胞表达;透射电镜观察大鼠海马组织超微结构变化;Western blot检测大鼠海马组织LKB1、p-AMPK/AMPK、p-mTOR/mTOR、Beclin1、p62、LC3-Ⅱ的蛋白表达水平。结果显示,与空白组比较,模型组大鼠逃避潜伏期升高,穿越平台次数、在平台象限停留时间减少;海马区神经元数量减少、形态受损,Aβ阳性细胞表达升高;LKB1、p-AMPK/AMPK、Beclin1、LC3-Ⅱ表达水平降低,p-mTOR/mTOR、p62表达水平升高。与模型组比较,固本健脑液低、高剂量组大鼠逃避潜伏期降低,穿越平台次数、在平台象限停留时间升高,神经元数量增多,Aβ阳性细胞表达减少,海马组织自噬溶酶体数量增加;固本健脑液低剂量组大鼠海马LKB1、Beclin1、LC3-Ⅱ表达水平升高;固本健脑液高剂量组大鼠海马组织LKB1、p-AMPK/AMPK、Beclin1、LC3-Ⅱ表达水平升高,p-mTOR/mTOR、p62表达水平降低。以上结果显示,固本健脑液可以改善AD大鼠认知障碍,其作用机制可能与激活LKB1/AMPK/mTOR信号通路,上调自噬水平有关。

关键词：阿尔茨海默病固本健脑液自噬 LKB1/AMPK/mTOR信号通路

I_(2)-DMSO-Mediated Multicomponent [2+1+1+1] Annulation Reaction via Ethyl Nitroacetate C-NO_(2), Bond Cleavage as a C1 Synthon: A Route to Multisubstituted β-Pyrrolidinones Derivatives with a Quaternary Center

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Chinese Journal of Chemistry 2024年第17期42卷 2029-2034页

作者： Zhi-cheng Yu xi Shen You Zhou xiang-Long chen Li-Sheng wang Yan-Dong Wu An-xin Wu National Key Laboratory of Green Pesticide International Joint Research Centerfor Intelligent BiosensorTechnologyand HealthCollegeof ChemistryCentral ChinaNormal UniversityWuhanHubei 430079China

A[2+1+1+1]cyclization reaction has been developed for the synthesis of multisubstituted 6-pyrrolidinones from commercially available aryl methyl ketones,primary amines,and ethyl *** this I_(2)-DMSO-meditated process,the C-NO_(2) bond of ethyl nitroacetate is cleaved,affording a C1 synthon,and the formation of two C-C and two C-N bonds and a quaternary carbon center are constructed in one *** method has good substrate compatibility and permits the late-stage modification of pharmaceutical compounds.

关键词： Cyclization Multisubstitutedβ-pyrrolidinones I_(2)-DMSO C1 building blocks Quaternary carbon center Late-stage modification Cracking

A high precision computing method for heat transfer in the process of oil-water displacement

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Journal of Hydrodynamics 2021年第5期33卷 958-969页

作者： Pan-pan Han Ke chen Dong-xi Liu Yun-xiang You Jin wang State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China Yazhou Bay Institute of Deepsea Technology Shanghai Jiao Tong UniversitySanya 572000China College of Ocean Science and Engineering Shanghai Maritime UniversityShanghai 201306China COTEC Offshore Engineering Solutions Beijing 100011China

The process of oil-water displacement is one of the key technologies in offshore underwater *** hot oil is contacting the normal-temperature water,the interfacial heat transfer should be investigated as the heat loss may result in wax precipitation and solidification which will reduce the flowing of oil and thus affect the *** for the numerical simulation of heat transfer,the calculation is costly as the underwater tank is usually large and the displacement period is long.A high precision computing method would greatly reduce the mesh ***,this research is performed to establish a high precision computing *** on volume of fluid(VOF),a new form of energy equation is *** equation is derived from temperature equation and the variable internal energy per volume is *** variable is additive and has a close relationship with volume *** algorithm implantation to OpenFOAM,two non-isothermal VOF solvers are established corresponding to temperature equation and the new equation *** an analytical solution is built,the two solvers are *** solver based on the new equation presents far more accurate results than the solver based on temperature *** energy weighted scheme is more reasonable than a linear temperature distribution for the mixture phase.

关键词： Multi-phase flow energy equation heat transfer oil-water displacement volume of fluid(VOF)

Mitigated reaction kinetics between lithium metal anodes and electrolytes by alloying lithium metal with low-content magnesium

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Journal of Energy Chemistry 2024年第8期95卷 644-650,I0014页

作者： Yang-Yang wang Ya-Nan wang Nan yao Shu-Yu Sun xiao-Qing Ding chen-xi Bi Qian-Kui Zhang Zhao Zheng cheng-bin Jin Bo-Quan Li Xue-Qiang Zhang Jia-Qi Huang School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China College of Materials and Chemistry China Jiliang UniversityHangzhou 310018ZhejiangChina

Lithium(Li)metal is regarded as a promising anode candidate for high-energy-density rechargeable ***,Li metal is highly reactive against electrolytes,leading to rapid decay of active Li metal ***,alloying Li metal with low-content magnesium(Mg)is proposed to mitigate the reaction kinetics between Li metal anodes and *** atoms enter the lattice of Li atoms,forming solid solution due to the low amount(5 wt%)of *** atoms mainly concentrate near the surface of Mg-alloyed Li metal *** reactivity of Mg-alloyed Li metal is mitigated kinetically,which results from the electron transfer from Li to Mg atoms due to the electronegativity *** on quantitative experimental analysis,the consumption rate of active Li and electrolytes is decreased by using Mgalloyed Li metal anodes,which increases the cycle life of Li metal batteries under demanding ***,a pouch cell(1.25 Ah)with Mg-alloyed Li metal anodes delivers an energy density of 340 Wh kg^(-1)and a cycle life of 100 *** work inspires the strategy of modifying Li metal anodes to kinetically mitigate the side reactions with electrolytes.

关键词： Lithium metal anodes Alloying Anode/electrolyte interface Reaction kinetics Pouch cell