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Effect of vanadium content on microstructure and properties of in situ TiC reinforced V_(x)FeCoNiCu multi-principal-element alloy matrix composites

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Journal of Iron and Steel Research International 2021年第11期28卷 1471-1480页

作者： chun-lei Tu xiao-dong Sun Jie Li He-guo Zhu Xiang-dong Li College of Mechanical Engineering Southeast UniversityNanjing 210094JiangsuChina Special Equipment Safety Supervision Inspection Institute of Jiangsu Province Nanjing 210036JiangsuChina College of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina

V_(x)FeCoNiCu high entropy alloy matrix composites reinforced by in situ TiC particles(10 vol.%),i.e.,V_(x)FeCoNiCu/TiC composites,were fabricated from V–Fe–Co–Ni–Cu–Ti–C system using vacuum inductive melting *** the content of vanadium increasing,the size of TiC particles decreased ***,vanadium agglomeration occurred *** reaction mechanism of the mixed powder(Fe,V,Ti and C)and the mechanical properties of obtaining V_(x)FeCoNiCu/TiC composites were *** was found that three reactions occurred(Fe-Ti-FeTi-Fe_(2)Ti,FeTi-Fe_(2)Ti-Fe-Ti and Ti-C-TiC)in the heating *** apparent activation energy for these three reactions was calculated and found to be 26.4,698.3 and 1879.0 kJ/mol,*** room temperature,tensile strength and elongation increased first and then decreased with the increase in vanadium content and the microhardness increased *** maximum tensile strength of the composites was determined to be 666 MPa,representing a 17.7%increase over that of FeCoNiCu/TiC high entropy alloy composites.

关键词： High entropy alloy matrix composite Vacuum inductive melting Reaction mechanism Apparent activation energy Tensile strength

Increasing the Content of β Phase of Poly(9,9-dioctylfluorene) by Synergistically Controlling Solution Aggregation and Extending Film-forming Time

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Chinese Journal of Polymer Science 2019年第7期37卷 664-673页

作者： Ya-Di liu Qiang Zhang Xin-Hong Yu Jian-Gang liu Yan-chun Han State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China

For poly(9,9-dioctylfluorene)(PFO),β phase (coplanar conformation with the intra-chain torsion angle of 165°) has a greater conjugation length and higher degree of order compared to those of α phase, which favors charge carrier transport. However, the highest content of β phase obtained so far is 45%. We propose to increase the content of β phase by promoting the solution aggregation of PFO molecules and extending film-forming time. For this purpose, 1,8-diiodooctane (DIO) is added to PFO o-xylene solution, which enhances the interaction of PFO chains and improves the planarity of PFO backbone, resulting in the formation of ordered aggregation. The aggregates act as nucleation centers to promote the formation of β phase. The content of β phase increases with increasing DIO concentration and reaches a platform of 39% as DIO is more than 4 vol%. Furthermore, the film is kept in a sealed environment with oxylene atmosphere for 3 h, thus the PFO molecules have enough time to diffuse to the crystallization front and achieve disorder-order transition. As a result, the crystallinity of PFO is improved significantly and the content of β phase increases to 52%, reaching the highest value reported so far.

关键词： β Phase Ordered aggregation Film-forming time Disorder-order transition

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多级串联膜电容去离子装置的脱盐性能

环境工程学报 2024年第1期18卷 63-70页

作者：陈瑞程谷佳蓉余铭浩马俊俊牛建瑞李耘科刘春河北科技大学环境科学与工程学院河北省污染防治生物技术实验室

膜电容去离子(membrane capacitive deionization,MCDI)技术具有的装置简单、易操作、易再生、成本低,无污染、节能等优势,使其成为一种新型的脱盐技术。为了提升MCDI的脱盐性能,将多个装置的进水串联,对每个装置单独加电来探究脱盐率,... 详细信息

膜电容去离子(membrane capacitive deionization,MCDI)技术具有的装置简单、易操作、易再生、成本低,无污染、节能等优势,使其成为一种新型的脱盐技术。为了提升MCDI的脱盐性能,将多个装置的进水串联,对每个装置单独加电来探究脱盐率,平均脱盐速率、单位能量脱盐量等指标对多级串联的影响。结果表明,在进水盐质量浓度、水力停留时间、电压等不同操作条件下,二、三级MCDI串联脱盐率都提高了约2、3倍,三级串联较二级串联的脱盐速率提升较小,但具有更高的能耗。综合比较,二级MCDI串联的脱盐性能更优,并获得了最佳的操作条件为1.5 g·L^(-1),0.375 min,1.2 V。在连续脱盐过程中,多级串联能够连续稳定的去除盐离子,并且具有较高的吸附容量,表明了连续脱盐的可行性。研究结果对多级MCDI脱盐工程化应用具有指导意义。

关键词：膜电容去离子多级串联脱盐性能参数优化连续脱盐

Configuration interaction study on low-lying states of AlCl molecule

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Chinese Physics B 2021年第5期30卷 320-327页

作者： xiao-Ying Ren Zhi-Yu xiao Yong liu Bing Yan Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China

High-level ab initio calculations of theΛ-S states for aluminum monoiodide(AlCl)molecule are performed by utilizing the explicitly correlated multireference configuration interaction(MRCI-F12)*** Davidson correction and scalar relativistic correction are investigated in the *** on the calculation by the MRCI-F12 method,the spin-orbit coupling(SOC)effect is investigated with the state-interacting *** adiabatic potential energy curves(PECs)of the 13Λ-S states and 24Ωstates are *** spectroscopic constants of bound states are determined,which are in accordance with the results of the available experimental and theoretical ***,the transition properties of 0^(+)(2)-X0^(+),1(1)-X0^(+),and 1(2)-X0^(+)transitions are predicted,including the transition dipole moments(TDMs),Franck-Condon factors(FCFs),and the spontaneous radiative lifetimes.

关键词： AlCl molecule MRCI-F12 potential energy curves spin-orbit coupling

Fault Feature Extraction of Diesel Engine Based on Bispectrum Image Fractal Dimension

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Chinese Journal of Mechanical Engineering 2018年第2期31卷 216-226页

作者： Jian Zhang Chang-Wen liu Feng-Rong Bi xiao-Bo Bi xiao Yang State Key Laboratory of Engines Tianjin University

Fault feature extraction has a positive effect on accurate diagnosis of diesel engine. Currently, studies of fault feature extraction have focused on the time domain or the frequency domain of signals. However, early fault signals are mostly weak energy signals, and time domain or frequency domain features will be overwhelmed by strong back?ground noise. In order consistent features to be extracted that accurately represent the state of the engine, bispectrum estimation is used to analyze the nonlinearity, non?Gaussianity and quadratic phase coupling(QPC) information of the engine vibration signals under different conditions. Digital image processing and fractal theory is used to extract the fractal features of the bispectrum pictures. The outcomes demonstrate that the diesel engine vibration signal bispectrum under different working conditions shows an obvious differences and the most complicated bispectrum is in the normal state. The fractal dimension of various invalid signs is novel and diverse fractal parameters were utilized to separate and characterize them. The value of the fractal dimension is consistent with the non?Gaussian intensity of the signal, so it can be used as an eigenvalue of fault diagnosis, and also be used as a non?Gaussian signal strength indicator. Consequently, a symptomatic approach in view of the hypothetical outcome is inferred and checked by the examination of vibration signals from the diesel motor. The proposed research provides the basis for on?line monitoring and diagnosis of valve train faults.

关键词： Engine fault diagnosis Bispectrum image processing Fractal Signal processing

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镧离子辅助混凝沉淀去除水体中氟离子的研究

应用化工 2024年第1期53卷 1-5页

作者：刘雨秋代林莉张永奎刘小龙王雅博四川大学化学工程学院四川成都610065 中国核动力研究设计院反应堆燃料及材料重点实验室四川成都610213

通过在含氟废水中投加可溶性镧盐,形成La-F胶体,再利用氯化铁-氧化钙-聚丙烯酰胺(PAM)混凝体系沉淀去除水体中的氟离子。利用较优的除氟工艺,即La^(3+)∶F-(摩尔比)=2∶3,pH=5,PAM∶F-(质量比)=5∶1,处理初始氟离子浓度为20~200 mg/L的... 详细信息

通过在含氟废水中投加可溶性镧盐,形成La-F胶体,再利用氯化铁-氧化钙-聚丙烯酰胺(PAM)混凝体系沉淀去除水体中的氟离子。利用较优的除氟工艺,即La^(3+)∶F-(摩尔比)=2∶3,pH=5,PAM∶F-(质量比)=5∶1,处理初始氟离子浓度为20~200 mg/L的含氟废水,可将出水氟离子浓度控制在1 mg/L以下。由于La^(3+)与F-之间较强的亲和作用,二者在水中可形成以LaF_(x)(OH)_(3-x)形式存在的胶体颗粒,后续加入的氯化铁和氧化钙破坏了胶体体系的稳定状态,并通过Fe^(3+)和PAM的凝聚-絮凝作用去除水体中的氟离子。该工艺的沉淀副产物可作为染料废水脱色用吸附剂,其对模拟污染物刚果红的吸附容量达337.8 mg/g,且大部分有效吸附发生在前3 min。

关键词：镧离子含氟废水胶体混凝沉淀

Diagnostic value of the fluoroscopic triggering 3D LAVA technique for primary liver cancer

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Hepatobiliary & Pancreatic Diseases International 2010年第2期9卷 159-163页

作者： Shen, xiao-Yong Chai, chun-Hua xiao, Wen-Bo Wang, Qi-Dong Zhejiang Univ Sch Med Affiliated Hosp 1 Dept Radiol Hangzhou 310003 Zhejiang Peoples R China

BACKGROUND: Primary liver cancer (PLC) is one of the common malignant tumors. Liver acquisition with acceleration volume acquisition (LAVA), which allows simultaneous dynamic enhancement of the hepatic parenchyma and vasculature imaging, is of great help in the diagnosis of PLC. This study aimed to evaluate application of the fluoroscopic triggering 3D LAVA technique in the imaging of PLC and liver vasculature. METHODS: The clinical data and imaging findings of 38 adults with PLC (22 men and 16 women; average age 52 years), pathologically confirmed by surgical resection or biopsy, were collected and analyzed. All magnetic resonance images were obtained with a 1.5-T system (General Electrics Medical Systems) with an eight-element body array coil and application of the fluoroscopic triggering 3D LAVA technique. Overall image quality was assessed on a 5-point scale by two experienced radiologists. All the nodules and blood vessel were recorded and compared. The diagnostic accuracy and feasibility of LAVA were evaluated. RESULTS: Thirty-eight patients gave high quality images of 72 nodules in the liver for diagnosis. The accuracy of LAVA was 97.2% (70/72), and the coincidence rate between the extent of tumor judged by dynamic enhancement and pathological examination was 87.5% (63/72). Displayed by the maximum intensity projection reconstruction, nearly all cases gave satisfactory images of branches III and IV of the hepatic artery. Furthermore, small early-stage enhancing hepatic lesions and the parallel portal vein were also well displayed. CONCLUSIONS: Sequence of LAVA provides good multi-phase dynamic enhancement scanning of hepatic lesions. Combined with conventional scanning technology, LAVA effectively and safely displays focal hepatic lesions and the relationship between tumor and normal tissues, especially blood vessels. (Hepatobiliary Pancreat Dis Int 2010; 9: 159-163)

关键词： liver neoplasm diagnosis imaging LAVA sequence

初诊糖尿病患者脂代谢指标及血BUN、UA检测的临床价值分析

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四川生理科学杂志 2024年第8期46卷 1767-1769,1848页

作者：吴煜刘芳孔小青南康区第一人民医院江西赣州341400

目的:探究初诊糖尿病患者脂代谢指标及尿素氮(Blood urea nitrogen,BUN)、尿酸(Uric acid,UA)检测的临床价值分析。方法:回顾性分析2020年1月至2023年11月期间,本院收治的初诊糖尿病患者共计64例;与此同时,从医院体检中心选取50例健康... 详细信息

目的:探究初诊糖尿病患者脂代谢指标及尿素氮(Blood urea nitrogen,BUN)、尿酸(Uric acid,UA)检测的临床价值分析。方法:回顾性分析2020年1月至2023年11月期间,本院收治的初诊糖尿病患者共计64例;与此同时,从医院体检中心选取50例健康体检人群作为对照组,通过查阅患者电子病历档案以及医院信息系统(Hospital information system,HIS)收集上述研究对象的基线资料、脂代谢水平、BUN以及UA水平;对两组研究对象的上述指标以及水平进行对比,并分析上述指标应用于初诊糖尿病患者对的临床价值。结果:初诊糖尿病组患者的甘油三酯(Triglyceride,TG)、总胆固醇(Total cholesterol,TC)以及低密度脂蛋白(Low density lipoprotein,LDL-C)水平显著高于健康对照组;高密度脂蛋白(High density lipoprotein,HDL-C)水平显著低于健康对照组,差异存在统计学意义(P<0.05);与此同时,初诊糖尿病组患者的BUN水平以及UA水平显著高于健康对照组,差异存在统计学意义(P<0.05);Logistic回归分析结果显示,研究对象的TG、TC、LDL-C、HDL-C、BUN以及UA水平同初诊糖尿病的发病之间存在一定的关联性(P<0.05)。结论:初诊糖尿病患者脂代谢指标及BUN、UA水平同健康对照组之间存在显著差异,对于糖尿病患者的早期诊断具有一定的评估价值,值得临床研究人员的借鉴应用。

关键词：初诊糖尿病脂代谢指标尿素氮尿酸临床价值分析

Selective and stable elimination of endosymbionts from multiple-infected whitefly Bemisia tabaci by feeding on a cotton plant cultured in antibiotic solutions

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Insect Science 2020年第5期27卷 964-974页

作者： Dong-xiao Zhao Zhi-chun Zhang Hong-Tao Niu Hui-Fang Guo Institute of Plant Protection Jiangsu Academy of Agricultural SciencesNanjingChina

The maternally heritable endosymbiont provides many ecosystem *** elimination of a specific symbiont and establishment of experimental host lines lacking certain symbionts enable the roles of a given symbiont to be *** whitefly Bemisia tabaci(Gennadius)in China harbors obligate symbiont Portiera infecting each in-dividual,as well as facultative symbionts,such as Hamiltonella,Rickettsia and Cardinium,with co-infections occurring relatively *** far no studies have evaluated the selectivity and efficacy of a specific symbiont elimination using antibiotics in whiteflies co-infected with different ***,no success has been achieved in estab-lishing certain symbiont-free *** *** this study,we treated Hamiltonella infected *** line,Hamiltonella-Rickettsia-co infected line and Hamiltonella-Cardinium co-infected line by feeding *** adults with cotton plants cultured in water containing ri-fampicin,ampicillin or a mixture of them,aiming to selectively curing symbiont infections and establishing stable symbiont-free *** found ampicillin selectively eliminated Cardinium without afecting Portiera,Hamiltonella and Rickettsia,although they coex-isted in the same host ***,all of the symbionts considered in our study can be removed by *** reduction of facultative symbionts occurred at a much quicker pace than obligate symbiont Portiera during rifampicin ***,we measured the stability of symbiont elimination in whitefly successive generations and established Rickettsia-infected and Cardinium-infected lines which are absent in natural *** results provide new protocols for selective elimination of symbionts co-existing in a host and establishment of different symbiont-infected host lines.

关键词： antibiotic treatment Bemisia tabaci co-infections endosymbionts infection frequency