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Tracking Catalytic Esterification of Naphthenic Acids in Crude Oil by ESI FT-ICR MS

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China Petroleum Processing & Petrochemical Technology 2016年第3期18卷 57-65页

作者： Li xiaohui Wu Bencheng Zhu Jianhua tao Xiujuan College of Chemistry and Chemical Engineering Xi'an Shiyou University College of Chemical Engineering China University of PetroleumBeijing Key Laboratory of Auxiliary Chemistry and Technology for Chemical Industry Shaanxi University of Science and Technology

The catalytic esterification reaction was used to decrease total acid number(TAN) of crude oil by converting naphthenic acids to naphthenic acid esters in the presence of Zn-Al hydrotalcite used as the catalyst and glycol used as the reactant. The crude oil and its corresponding esterified oil were characterized by the negative-ion electrospray ionization(ESI) Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR MS). Six acidic class species, O_2, O_1, N_1, N_2, N_1O_1 and N_1O_2 were assigned in the negative-ion spectrum both in the crude oil and its esterified oil. Among the identified acidic compounds, the O2 class was dominant. The relative abundance of O_2 class species was much higher than other acidic class species in crude oil, while it was significantly decreased after esterification. The most abundant O_2 class species had a carbon number of 30-34 and a double-bond equivalence(DBE) value of 5 before and after esterification. It could be concluded that the naphthenic acids in crude oil can be esterified to lower its TAN value, and each of them seems to exhibit identical esterification efficiency approximately due to the similar DBE versus the-carbon number distribution before and after esterification.

关键词： naphthenic acids crude oil esterification ESI FT-ICR MS

Optimizing energy harvesting performance by tailoring ferroelectric/relaxor behavior in KNN-based piezoceramics

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Journal of Advanced Ceramics 2022年第6期11卷 935-944页

作者： Yu HUAN Xinjian WANG Wenyu YANG Limin HOU Mupeng ZHENG tao WEI xiaohui WANG School of Materials Science and Engineering University of JinanJinan 250022China Key Laboratory of Advanced Functional Materials Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Piezoelectric energy harvesters(PEHs)fabricated using piezoceramics could convert directly the mechanical vibration energy in the environment into electrical *** high piezoelectric charge coefficient(d_(33))and large piezoelectric voltage coefficient(g_(33))are key factors for the high-performance ***,high d_(33)and large g_(33)are difficult to simultaneously achieve with respect to g_(33)=d_(33)/(e_(0)e_(r))and d_(33)=2Qe_(0)e_(r)P_(r).Herein,the energy harvesting performance is optimized by tailoring the CaZrO_(3)content in(0.964−x)(K_(0.52)Na_(0.48))(Nb_(0.96)Sb_(0.04))O_(3)-0.036(Bi_(0.5)Na_(0.5))ZrO_(3)-xCaZrO_(3)***,the doping CaZrO_(3)could enhance the dielectric relaxation due to the compositional fluctuation and structural disordering,and thus reduce the domain size to~30 nm for x=0.006 *** nanodomains switch easily to external electric field,resulting in large ***,the rhombohedral-orthorhombic-tetragonal phases coexist in x=0.006 sample,which reduces the polarization anisotropy and thus improves the piezoelectric *** multiphase coexistence structures and miniaturized domains contribute to the excellent piezoelectric properties of d_(33)(354 pC/N).Furthermore,the dielectric relative permittivity(ε_(r))reduces monotonously as the CaZrO_(3)content increases due to the relatively low ion polarizability of Ca^(2+)and Zr^(4+).As a result,the optimized energy conversion coefficient(d_(33)×g_(33),5508×10^(−15)m^(2)/N)is achieved for x=0.006 *** importantly,the assembled PEH with the optimal specimen shows the excellent output power(~48 mW)and lights up 45 red commercial light-emitting diodes(LEDs).This work demonstrates that tailoring ferroelectric/relaxor behavior in(K,Na)NbO_(3)-based piezoelectric ceramics could effectively enhance the electrical output of PEHs.

关键词： piezoelectric energy harvesters(PEHs) potassium sodium niobate(KNN) relaxor ferroelectric miniaturized domains multiphase coexistence

Stabilizing MXene suspension with polyhydric alcohols

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Journal of Materials Science & Technology 2023年第34期165卷 219-224页

作者： Renfei Cheng Junchao Wang tao Hu Yiming Zhao Yan Liang xiaohui Wang Yanchun Zhou Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Institute of Materials Science and Devices School of Materials Science and EngineeringSuzhou University of Science and TechnologySuzhou 215009China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

MXenes have promises in myriad applications by virtue of two-dimensional nature and adjustable functional *** achieve the applications,MXenes are always first prepared in the form of aqueous ***,fast degradation caused by the attack of dissolved oxygen and water molecules is the main obstacle to the application of *** has come to light that the degradation preferentially takes place at defective sites and edges where defects *** tackle this problem and increase the stability,herein,using Ti_(3)C_(2)T_(x)MXene as a model material,we report a simple yet efficient strategy for long term storage of MXene suspension by introducing glycerol,a typical polyhydric *** effectiveness of the strategy is evidenced by structural compositional and morphological *** protects the defective sites of MXene flakes through restricting water and/or oxygen molecules from reactive *** is supported by ab initio molecular dynamics simulations that form hydrogen bonds between MXene and glycerol molecules just over defective *** this mechanism,other polyhydric alcohols,such as ethylene glycol and propylene glycol,are also effective in stabilizing Ti_(3)C_(2)T_(x)MXene *** strategy based on polyhydric alcohols has the potential to be extended to other MXenes,solving the most urgent challenge in the field of MXene engineering.

关键词： MXene Stability Polyhydric alcohols Glycerol Ethylene glycol and propylene glycol

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船舶活动知识图谱可视分析方法

计算机辅助设计与图形学学报 2024年第8期36卷 1194-1204页

作者：刘建湘陈晓慧刘海砚张兵叶林易万潇刘涛中国人民解放军93116部队沈阳110000 中国人民解放军战略支援部队信息工程大学数据与目标工程学院郑州450000 中国人民解放军61578部队十堰442000

随着全球海事贸易的高速发展,对船舶活动进行可视分析的需求越来越大,用户在没有非常专业的知识背景下,难以快速地选择合适的可视化方法进行船舶活动分析,面临“冷启动”问题.为此,提出船舶活动知识图谱可视分析方法.基于多源异构的船... 详细信息

随着全球海事贸易的高速发展,对船舶活动进行可视分析的需求越来越大,用户在没有非常专业的知识背景下,难以快速地选择合适的可视化方法进行船舶活动分析,面临“冷启动”问题.为此,提出船舶活动知识图谱可视分析方法.基于多源异构的船舶活动数据,构建包含时间、地点、船舶和活动4类船舶活动要素的船舶活动知识图谱,并结合船舶活动分析需求,设计船舶对象特征分析、船舶活动事件分析、船舶活动关联分析和船舶活动时空分析4种分析任务;在船舶活动知识图谱的基础上,提出基于活动要素的船舶活动可视分析方法,并结合过滤、关联和导航等交互方式,设计船舶活动知识图谱可视分析模型.以AIS数据和“沸腾环贸”海上事件数据作为船舶活动数据,基于所提出的船舶活动知识图谱可视分析模型,开发了船舶活动知识图谱可视分析原型系统,实验结果表明,该系统可以为用户推荐相对合适的可视化方法,为船舶活动的分析提供更多的视角;也验证了如禁渔期等特殊情况造成船舶活动规律变化等结论.

关键词：船舶活动船舶事件知识图谱时空活动可视分析

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Single Cu atom dispersed on S,N-codoped nanocarbon derived from shrimp shells for highly-efficient oxygen reduction reaction

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Nano Research 2022年第7期15卷 5995-6000页

作者： Hao Zhang Qingdi Sun Qian He Ying Zhang xiaohui He tao Gan Hongbing Ji Fine Chemical Industry Research Institute School of ChemistrySun Yat-sen UniversityGuangzhou 510275China School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China School of Chemical Engineering Guangdong University of Petrochemical TechnologyMaoming 525000China

Recently,Cu-based single-atom catalysts(SACs)have garnered increasing attention as substitutes for platinum-based catalysts in the oxygen reduction reaction(ORR).Therefore,a facile,economical,and efficient synthetic methodology for the preparation of a high-performance Cu-based SAC electrocatalyst for the ORR is extremely desired,but is also significantly *** this study,we propose a ball-milling method to synthesize isolated metal SACs embedded in S,N-codoped nanocarbon(MNSDC,M=Cu,Fe,Co,Ni,Mn,Pt,and Pd).In particular,the Cu-NSDC SACs exhibit high electrochemical activity for the ORR with half-wave potential(E_(1/2))of 0.84 V(*** hydrogen electrode(RHE),20 mV higher than Pt/C)in alkaline electrolyte,excellent stability,and electrocatalytic *** functional theory(DFT)calculations demonstrated that the desorption of OH*intermediates was the rate-determining step over *** study creates a pathway for high-performance ORR single atomic electrocatalysts for fuel cell applications and provides opportunities to convert biowaste materials into commercial opportunities.

关键词： ball milling oxygen reduction reaction single-atom catalysis shrimp shell S,N-codoped nanocarbon

Multimodal interaction design and application in augmented reality for chemical experiment

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Virtual Reality & Intelligent Hardware 2020年第4期2卷 291-304页

作者： Mengting XIAO Zhiquan FENG xiaohui YANG tao XU Qingbei GUO Department of Information Science and Engineering University of JinanJinan 250022China Shandong Provincial Key Laboratory of Network Based Intelligent Computing Jinan 250022China

Background Augmented reality classrooms have become an interesting research topic in the field of education,but there are some ***,most researchers use cards to operate experiments,and a large number of cards cause difficulty and inconvenience for ***,most users conduct experiments only in the visual modal,and such single-modal interaction greatly reduces the users'real sense of *** order to solve these problems,we propose the Multimodal Interaction Algorithm based on Augmented Reality(ARGEV),which is based on visual and tactile feedback in Augmented *** addition,we design a Virtual and Real Fusion Interactive Tool Suite(VRFITS)with gesture recognition and intelligent *** The ARGVE method fuses gesture,intelligent equipment,and virtual *** use a gesture recognition model trained by a convolutional neural network to recognize the gestures in AR,and to trigger a vibration feedback after a recognizing a five finger grasp *** establish a coordinate mapping relationship between real hands and the virtual model to achieve the fusion of gestures and the virtual *** The average accuracy rate of gesture recognition was 99.04%.We verify and apply VRFITS in the Augmented Reality Chemistry Lab(ARCL),and the overall operation load of ARCL is thus reduced by 29.42%,in comparison to traditional simulation virtual *** We achieve real-time fusion of the gesture,virtual model,and intelligent equipment in *** with the NOBOOK virtual simulation experiment,ARCL improves the users'real sense of operation and interaction efficiency.

关键词： Augmented reality Gesture recognition Intelligent equipment Multimodal Interaction Augmented Reality Chemistry Lab

计算机导航辅助骨盆软骨肉瘤切除手术预后分析

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中华骨科杂志 2024年第10期44卷 676-684页

作者：李卓宇刘巍峰邓志平金韬李远蒋协远鱼锋张清牛晓辉首都医科大学附属北京积水潭医院(北京大学第四临床医学院)骨肿瘤科北京100035 国家骨科医学中心北京100035 北京市创伤骨科研究所北京100035

目的探讨计算机导航手术和传统手术对骨盆软骨肉瘤功能和肿瘤学结局的影响。方法回顾性分析2000年1月至2017年12月北京积水潭医院手术治疗的骨盆软骨肉瘤136例,男65例、女71例,年龄(46.07±13.37)岁(范围13~73岁);原发性120例、继发性16... 详细信息

目的探讨计算机导航手术和传统手术对骨盆软骨肉瘤功能和肿瘤学结局的影响。方法回顾性分析2000年1月至2017年12月北京积水潭医院手术治疗的骨盆软骨肉瘤136例,男65例、女71例,年龄(46.07±13.37)岁(范围13~73岁);原发性120例、继发性16例,其中普通型软骨肉瘤109例(病理分化程度分级Ⅰ级7例、Ⅱ级83例、Ⅲ级19例)、去分化软骨肉瘤21例、间叶型3例、透明细胞型2例、黏液型1例;12例为多发骨软骨瘤病恶变;Enneking分期ⅠB期104例、ⅡB期32例;按解剖部位分类为骨盆Ⅰ区14例、Ⅱ区1例、Ⅲ区13例、Ⅰ+Ⅱ区16例、Ⅰ+Ⅳ区16例、Ⅱ+Ⅲ区47例、Ⅰ+Ⅱ+Ⅲ区25例、Ⅰ+Ⅱ+Ⅲ+Ⅳ区4例。所有病例按照切除边界分为囊内、边缘、广泛切除,计算机导航手术(导航组)45例、非导航手术组91例。比较两组患者人口学资料、术前肿瘤分期、手术特征、外科边界分类、肿瘤学指标、重建方法、术后并发症及骨与软组织肿瘤功能评分(Musculoskeletal Tumor Society score,MSTS)。结果导航组未发生计算机导航系统相关的手术并发症。导航组与非导航组术后随访时间分别为(68.56±37.82)个月(范围6~197个月)和(76.85±52.60)个月(范围5~225个月)。导航组和非导航组MSTS分别为(25.43±2.854)和(24.56±4.193)分,差异无统计学意义(t=1.191,P=0.237)。导航组边缘切除10例、广泛切除35例,非导航组囊内切除12例、边缘切除32例、广泛切除47例,差异有统计学意义(χ^(2)=10.977,P=0.004)。导航组术后局部复发4例(8.9%,4/45),非导航组20例(21.9%,20/91),差异有统计学意义(χ^(2)=4.040,P=0.046);导航组复发患者最终截肢2例、再次切除2例,非导航组最终截肢6例、再次切除14例。导航组3例(7%,3/45)发生远处转移,非导航组18例(20%,18/91),差异有统计学意义(χ^(2)=4.478,P=0.034)。导航组和非导航组术后五年生存率分别为93.3%、72.6%,三年、五年无进展生存率为91.1%、84.4%和74.8%、62.7%,差异均有统计学意义(χ^(2)=5.081,P=0.024;χ^(2)=6.800,P=0.009)。导航组ⅠB期肿瘤五年生存率为96.7%、非导航组为84.5%,差异有统计学意义(χ^(2)=3.897,P=0.048);导航组ⅡB期肿瘤五年生存率为75.0%、非导航组为35.0%,差异无统计学意义(P>0.05)。术后并发症包括术后感染15例、深静脉血栓形成16例、双下肢不等长14例、假体脱位2例、淋巴水肿2例、疝气1例及异体骨吸收1例,两组各并发症发生率的差异无统计学意义(P>0.05)。结论计算机导航辅助骨盆软骨肉瘤切除手术相较于传统手术有利于获得安全的肿瘤外科边界,降低肿瘤局部复发率从而有效改善患者生存预后。

关键词：外科手术,计算机辅助骨盆软骨肉瘤外科边界

鄂尔多斯盆地南部古生界天然气地球化学特征与成因

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天然气地球科学 2024年第9期35卷 1616-1625页

作者：张涛王晓锋金晓辉孟庆强王怡然陈晓艳张雯张隽中国石化石油勘探开发研究院北京100083 西北大学地质学系/大陆动力学国家重点实验室陕西西安710069

鄂尔多斯盆地南部古生界天然气地球化学特征与北部存在较大差异,除了由于烃源岩有机质成熟度升高造成的干燥系数增加、甲烷碳同位素组成较重之外,盆地南部上古生界天然气中CO_(2)气体含量更高、普遍出现甲、乙烷碳同位素组成倒转等现象... 详细信息

鄂尔多斯盆地南部古生界天然气地球化学特征与北部存在较大差异,除了由于烃源岩有机质成熟度升高造成的干燥系数增加、甲烷碳同位素组成较重之外,盆地南部上古生界天然气中CO_(2)气体含量更高、普遍出现甲、乙烷碳同位素组成倒转等现象。以气体地球化学为主要研究手段,在系统对比盆地古生界天然气南北差异的基础上,讨论天然气成因与来源。盆地南部上古生界天然气主体以高过成熟煤型气为主,其中部分地区的部分样品气体地球化学指标体现了下古生界海相烃源特征。盆地南部上古生界天然气整体出现甲、乙烷碳同位素组成倒转现象,这与上古生界与下古生界不同成因类型天然气混合作用有关。具有相对较高的乙烷含量和较轻乙烷碳同位素组成的下古生界油型气不同程度的混合是造成盆地南部上古生界天然气碳同位素组成倒转的主要原因。盆地南部下古生界天然气地球化学指标体现了典型海相烃源特征,同时不排除少量上古生界煤型气混入的可能。

关键词：碳同位素组成倒转天然气成因与来源混合作用鄂尔多斯盆地南部

Closed-loop cobalt recycling from spent lithium-ion batteries based on a deep eutectic solvent (DES) with easy solvent recovery

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Journal of Energy Chemistry 2022年第9期31卷 532-538,I0015页

作者： Taibai Li Yige Xiong xiaohui Yan tao Hu Siqi Jing Zhongjie Wang Xiang Ge Department of Materials and Metallurgy Guizhou UniversityGuiyang 550025GuizhouChina

Efficient recycling technology for the rapid growth of spent lithium-ion batteries(LIBs)is essential to tackle the resources and environmental *** approach has attracted extensive research due to its potential to reduce the consumption of energy and threat to the ***,the simultaneous realization of green,efficient and closed-loop recycling is still ***,we report a closed-loop and highly efficient approach to recycle lithium cobalt oxide from spent LIBs based on a choline chloride:oxalic acid(ChCl:OA)type deep eutectic solvent(DES).An ultrafast leaching process is observed at 180°C for 10 s with no observable *** energy barrier during leaching is calculated to be 113.9 kJ/***,the solubility of cobalt ions can be reversibly tuned by simply adding/evaporating deionized water,thus avoiding the addition of precipitant and enabling the easy recovery of the leaching solvent for realizing a closed-loop recycling *** simultaneous realization of high efficiency,green and closed-loop process is expected to push the DES into practical application for recycling the electrodes of LIBs.

关键词： Lithium-ion batteries recycle Deep eutectic solvent Closed-loop High efficiency Solvent recovery