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Chinese Journal of Mechanical Engineering 2018年第4期31卷 168-181页

作者： Rui-ting tong Geng Liu Shaanxi Engineering Laboratory for Transmissions and Controls Northwestern Polytechnical University

Textured surfaces are widely used in engineering components as they can improve tribological properties of sliding contacts, while the detailed behaviors of nanoscale reciprocating sliding contacts of textured surfaces are still lack of study. By using multiscale method, two dimensional nanoscale reciprocating sliding contacts of textured surfaces are investigated. The influence of indentation depth, texture shape, texture spacing, and tip radius on the average friction forces and the running-in stages is studied. The results show that the lowest indentation depth can make all the four textured surfaces reach steady state. Surfaces with right-angled trapezoid textures on the right side are better for reducing the running-in stage, and surfaces with right-angled trapezoid textures on the left side are better to reduce wear. Compared with other textured surfaces, the total average friction forces can be reduced by 82.94%–91.49% for the case of the contact between the tip with radius R = 60rand the isosceles trapezoid textured surface. Besides,the total average friction forces increase with the tip radii due to that bigger tip will induce higher contact areas. This research proposes a detailed study on nanoscale reciprocating sliding contacts of textured surfaces, to contribute to design textured surfaces, reduce friction and wear.

关键词： Nanoscale Reciprocating sliding contacts Textured surface Structure parameters Indentation depth

A Local Region Molecular Dynamics Simulation Method for Nanoscale Sliding Contacts

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Chinese Journal of Mechanical Engineering 2018年第5期31卷 119-126页

作者： Rui-ting tong Geng Liu Tian-Xiang Liu Shaanxi Engineering Laboratory for Transmissions and Controls Northwestern Polytechnical University Xi’an 710072 China Institute for Mechanics and Fluid Dynamics TU Bergakademie Freiberg Lampadiusstr. 4 09596 Freiberg Germany

Computational e ciency and accuracy always conflict with each other in molecular dynamics(MD) simulations. How to enhance the computational e ciency and keep accuracy at the same time is concerned by each corresponding researcher. However, most of the current studies focus on MD algorithms, and if the scale of MD model could be reduced, the algorithms would be more meaningful. A local region molecular dynamics(LRMD) simulation method which can meet these two factors concurrently in nanoscale sliding contacts is developed in this paper. Full MD simulation is used to simulate indentation process before sliding. A criterion called contribution of displacement is presented, which is used to determine the e ective local region in the MD model after indentation. By using the local region, nanoscale sliding contact between a rigid cylindrical tip and an elastic substrate is investigated. Two two?dimensional MD models are presented, and the friction forces from LRMD simulations agree well with that from full MD simulations, which testifies the e ectiveness of the LRMD simulation method for two?dimensional cases. A three?dimensional MD model for sliding contacts is developed then to show the validity of the LRMD simulation method further. Finally, a discussion is carried out by the principles of tribology. In the discussion, two two?dimensional full MD models are used to simulate the nanoscale sliding contact problems. The results indicate that original smaller model will induce higher equivalent scratching depth, and then results in higher friction forces, which will help to explain the mechanism how the LRMD simulation method works. This method can be used to reduce the scale of MD model in large scale simulations, and it will enhance the computational e ciency without losing accuracy during the simula?tion of nanoscale sliding contacts.

关键词： Local region molecular dynamics simulation Nanoscale Sliding contacts Contribution of displacement

Characterization of Formation Kinetics of Self-Assembled Thiol Monolayers on Gold by Electrochemical Impedance Spectroscopy

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Chinese Chemical Letters 2000年第12期11卷 1085-1088页

作者： Peng DIAO Min GUO Ru ting tong Department of Chemistry Hebei Teacher’s UniversityShijiazhuang 050016 Department of Traditional Chinese Pharmacy Traditional Chinese Medicine CollegeHebei Medical UniversityShijiazhuang 050091

Self-assembled monolayers of octadecanethiol (ODT) on gold have been studied by electrochemical impedance spectroscopy (EIS). The fractional coverage has been examined as a function of immersion time of Au in ODT deposition solution. The fractional coverage exhibits two distinct adsorption steps: an initial rapid step followed by a slow one. The fractional coverage of ODT monolayer increases sharply from zero to more than 99% of its maximum within the first minute. However. it takes a day for the fractional coverage to approach its final value.

关键词： self-assembled thiol monolayer electrochemical impedance spectroscopy adsorption kinetics

Analysis of Metal Forming in Two-Roll Cross Wedge Rolling Process Using Finite Element Method

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Journal of Iron and Steel Research International 2009年第1期16卷 38-43页

作者： WANG Min-ting LI Xue-tong DU Feng-shan College of Mechanical and Engineering Yanshan University Qinhuangdao 066004 Hebei China

A simulation model for two-roll cross wedge rolling （CWR） was presented by using three-dimensional rigid-plastic finite element method （FEM）. The whole forming process of CWR, including knifing zone, guiding zone, stretching zone, and sizing zone, was simulated using the model in which dynamic adaptive remeshing technology for tetrahedral solid elements was used to fix element distortion. Based on the simulation results, the distributions of metal flow field, strain field, and damage field, and the geometry of the workpiece＇s end were analyzed. These results could provide theoretical guidance for realizing net shaping and reasonable design of tools.

关键词： cross wedge rolling finite element method plastic forming simulation

Primary pancreatic lymphoma diagnosed by endoscopic ultrasound-guided fine needle biopsy

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Hepatobiliary & Pancreatic Diseases International 2022年第1期21卷 99-102页

作者： Ning-Xin Zhu Xiao-Yan Wang ting tong Jia-Hao Xu Yuan-Yuan Yang Li Tian Gastroenterology Department of the Third Xiangya Hospital Central South UniversityChangsha 410013China

To the Editor:Primary pancreatic lymphoma(PPL)is extremely rare,account-ing for 1%of extra-nodal lymphomas and less than 0.5%of pan-creatic masses[1].Both cytological and histological analyses are required to confirm the diagnosis of *** main treatments include chemotherapy and radiotherapy[2].Pancreatic resection alone does not improve the survival rate[3].Hence,it is necessary to differentiate PPL from other malignant tumors before surgery.

关键词： needle diagnosis chemotherapy

The efficacy and safety of endoscopic ultrasound-guided fine-needle biopsy in gallbladder masses

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Hepatobiliary & Pancreatic Diseases International 2023年第6期22卷 632-638页

作者： ting tong Li Tian Min-Zi Deng Xue-Jie Chen Tian Fu Ke-Jia Ma Jia-Hao Xu Xiao-Yan Wang Endoscopic Center Department of Gastroenterologythe Third Xiangya HospitalCentral South UniversityNo.138 Tongzipo Road Yuelu DistrictChangsha 410013China

Background: Endoscopic ultrasound-guided fine-needle biopsy(EUS-FNB) is a widely used modality for acquiring various target samples, but its efficacy in gallbladder masses is unknown. The aim of this retrospective study was to evaluate the efficacy and safety of EUS-FNB in patients with gallbladder masses. Methods: The study samples were composed of patients from March 2015 to July 2019 who needed to identify the nature of gallbladder masses through EUS-FNB. The outcomes of this study were the adequacy of specimens, diagnostic yields, technical feasibility, and adverse events of the EUS-FNB in gallbladder masses. Results: A total of 27 consecutive patients with a median age of 58 years were included in this study. The 22-gauge FNB needle was feasible in all lesions. The median follow-up period of the patients was 294 days. The specimens sufficient for diagnosis account for 89%(24/27) and 93%(25/27) in cytology and histology, respectively. The overall diagnostic yields for malignancy showed the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 95.45% [95% confidence interval(CI): 75.12%-99.76%], 100%(95% CI: 46.29%-10 0%), 10 0%(95% CI: 80.76%-100%), 83.33%(95% CI: 36.48%-99.12%), and 96.30%(95% CI: 80.20%-99.99%), respectively. The subgroup analysis revealed that FNB could obtain sufficient specimens and high diagnostic yields in both gallbladder mass < 20.5 mm group and ≥20.5 mm group. One patient experienced mild abdominal pain after the procedure and recovered within one day. Conclusions: EUS-FNB is a reasonable diagnostic tool for the pretreatment diagnosis of patients with gallbladder masses, especially for patients who may miss the opportunity of surgery and need sufficient specimens to identify the pathological type so as to determine chemotherapy regimens. Further largescale studies are needed to confirm our conclusion.

关键词： Adverse events Diagnostic yields Endoscopic ultrasound-guided fine-needle biopsy Gallbladder masses Specimen adequacy

ZrO2/聚偏氟乙烯复合材料介电性能及松弛行为

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复合材料学报 2019年第9期36卷 2051-2058页

作者：童婷马凯陕西理工大学材料科学与工程学院

通过熔融法制备了ZrO2/聚偏氟乙烯(PVDF)复合材料,采用SEM、XRD和FTIR对其形貌和结构进行分析,结果表明,ZrO2分布较为均匀,ZrO2/PVDF复合材料主要含α相和少量γ相。采用宽频介电谱(BDS)测试,ZrO2/PVDF复合材料介电常数ε′随ZrO2含量... 详细信息

通过熔融法制备了ZrO2/聚偏氟乙烯(PVDF)复合材料,采用SEM、XRD和FTIR对其形貌和结构进行分析,结果表明,ZrO2分布较为均匀,ZrO2/PVDF复合材料主要含α相和少量γ相。采用宽频介电谱(BDS)测试,ZrO2/PVDF复合材料介电常数ε′随ZrO2含量的增加而增加,而介电损耗tanδ保持定值,表明ZrO2的加入可以显著提高ZrO2/PVDF复合材料的介电性能。经计算ZrO2/PVDF复合材料介电模量M″和活化能,发现有玻璃化转变峰、缺陷峰和界面极化峰存在,而加入ZrO2后,ZrO2/PVDF复合材料活化能增加。

关键词： ZrO2 聚偏氟乙烯(PVDF) 介电性能松弛行为活化能

Electrochemical Impedance Study of Schiff Base by Means of Self-assembled Monolayer

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Chinese Chemical Letters 2001年第12期12卷 1101-1104页

作者： Ke Qiang DING Zhen Bin JIA Qing Fei WANG Na TIAN Ru ting tong Xin Kui WANG Hui Bo SHAO Department of Chemistry Hebei Teacher's University Institute of Coal Chemistry Chinese Academy of Science Department of Chemistry Capital Normal University

In this work, the self-assembled monolayer of Schiff base was first investigated using electrochemical impedance spectroscopy (EIS). The complexation Of Cu2+ with the Schiff base: was also detected with EIS method. The approximate linear relationship between Cu2+ and the reaction resistance (R-r) was observed. All the results suggest that the electrochemical property of Schiff base could be studied conveniently by means of forming self-assembled monolayer.

关键词： Schiff base self-assembled monolayer electrochemical impedance spectroscopy complexation

ERG3 and ERG11 genes are critical for the pathogenesis of Candida albicans during the oral mucosal infection

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International Journal of Oral Science 2018年第1期10卷 57-64页

作者： Yujie Zhou Min Liao Chengguang Zhu Yao Hu ting tong Xian Peng Mingyun Li Mingye Feng Lei Cheng Biao Ren Xuedong Zhou State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & West China Hospital of Stomatology Sichuan University

The hyphal development of Candida albicans(***) has been considered as an essential virulent factor for host cell ***, the missing link between hyphae and virulence of *** is also been discovered. Here, we identified that the null mutants of ERG3 and ERG11, two key genes in ergosterol biosynthesis pathway, can form typical hyphae but failed to cause the oral mucosal infection in vitro and in vivo for the first time. In particular, the erg3Δ/Δ and erg11Δ/Δ strains co-cultured with epithelial cells significantly reduced the adhesion, damage, and cytokine(interleukin-1α(IL-1α)) production, whereas the invasion was not affected in vitro. Importantly, they were incapable of extensive hyphal invasion, formation of micro-abscesses, and tongue epithelium damage compared to wild type due to the decrease of the colonization and epithelial infection area in a murine oropharyngeal candidiasis model. The fluconazole(FLC), an antifungal targeted at ergosterol biosynthesis, relieved the epithelial infection of *** vitro and in vivo even under non-growth inhibitory dosage confirming the virulent contribution of ergosterol biosynthesis pathway. The erg3Δ/Δ and erg11Δ/Δ strains were cleared by macrophages similar to wild type, whereas their virulence factors including agglutinin-like sequence 1(Als1), secreted aspartyl proteinase 6(Sap6), and hyphal wall protein-1(Hwp1) were significantly reduced indicated that the non-toxicity might not result from the change on immune tolerance but the defective virulence. The incapacity of erg3Δ/Δ and erg11Δ/Δ in epithelial infection highlights the contribution of ergosterol biosynthesis pathway to *** pathogenesis and fluconazole can not only eliminate the fungal pathogens but also reduced their virulence even at low dosage.

关键词：

THE RESEARCH ON MODEL OF PROBABILITY DAMAGE TOLERANCE ANALYSIS

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Chinese Journal of Aeronautics 1993年第4期 253-260页

作者： Liu Wen-ting,Luo Yi,tong Ming-bo (Beijing University of Aeronautics and Astronautics,Beijing,China,100083)

A new model of probability damage tolerance analysis is presented. It is composed ofua-t" random crack growth model and reliability analysis model which are based onthe life-failure criterion. The former establishes distribution function oflife for arbitrarycrack length by using reasonable "a-t" relation and statistically analysing life data forarbitrary given crack length. The latter indicates that safe reliability R corresponding togiven life tis probability of random critical life exceeding t. This new model can remedythe weakness of previous analysis model of probability damage tolerance, which is composedof "da/dt" random process model and "a-a" （or "K-K" ） reliabilityinterference model, and furthermore, it is very convenient to engineering use.

关键词： THE RESEARCH ON MODEL OF PROBABILITY DAMAGE TOLERANCE ANALYSIS