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Ag/C nanoparticles catalysed aerobic oxidation of diaryl and aryl（hetero） methylenes into ketones

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Nano Research 2017年第9期10卷 3261-3267页

作者： Shuangxi Guo Qi Zhang hongbo Li Huifang Guo wei He Tsinghua-Peking Joint Center for Life Sciences and School of Life Sciences Tsinghua University Beijing 100084 China Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences & Peking Union Medical College Beijing I O00SO China School of Pharmaceutical Sciences Tsinghua University 8eijing 100084 China

The aerobic oxidation of diaryl and aryl(hetero) methylenes into ketones, catalyzed by Ag/C nanoparticles under mild conditions, was successfully developed. This method features a wide scope of substrates, good yields... 详细信息

关键词： nanoparticle aerobic oxidation diaryl methylenes ketones

Optical properties and applications of SnS_(2) SAs with different thickness

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Opto-Electronic Advances 2021年第10期4卷 1-10页

作者： Mengli Liu hongbo Wu Ximei Liu Yaorong Wang Ming Lei Wenjun Liu wei Guo Zhiyi wei State Key Laboratory of Information Photonics and Optical Communications School of ScienceP.O.Box 91Beijing University of Posts and TelecommunicationsBeijing 100876China School of Physics Beijing Institute of Technology5 South Zhongguancun StreetBeijing 100081China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

Q-switched lasers have occupied important roles in industrial applications such as laser marking,engraving,welding,and cutting due to their advantages in high pulse energy.Here,SnS_(2)-based Q-switched lasers are implemented.Consid-ering that SnS_(2) inherits the thickness sensitive optical characteristics of TMD,three kinds of SnS2 with different thick-ness are characterized in terms of nonlinearity and used to realize the Q-switched pulses under consistent implementa-tion conditions for comparison tests.According to the results,the influence of thickness variation on the nonlinear per-formance of saturable absorber,such as modulation depth and absorption intensity,and the influence on the correspond-ing laser are analyzed.In addition,compared with other traditional saturable absorbers,the advantage of SnS_(2) in realiz-ing ultrashort pulses is also noticed.Our work explores the thickness-dependent nonlinear optical properties of SnS_(2),and the rules found is of great reference value for the establishment of target lasers.

关键词： nonlinear optical materials fiber laser Q-switching

Lane Departure Assistance Coordinated Control System for In-Wheel Motor Drive Vehicles Based on Dynamic Extension Boundary Decision

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Journal of Systems Science & Complexity 2020年第4期33卷 1040-1063页

作者： WANG hongbo CUI wei YE Bin School of Automotive and Transportation Engineering Hefei University of TechnologyHefei 230009China Anhui Intelligent Vehicle Engineering Laboratory Hefei 230009China

Aiming at the advantages in active safety control of in-wheel motor drive vehicles, the classified decision-control-execution is proposed to the lane departure assistance system under the premise of ensuring the stability of the vehicle. The dynamic extension boundaries which vary with vehicle speed, road curvature and road adhesion coefficient are designed in the decision layer by using the neural network algorithm, which divides different dangerous degrees into different decision regions.The active differential steering controller, the electronic differential controller and their coordinated control strategy are designed in the control layer, and the corresponding control is carried out among different decision regions. In order to avoid the dangerous situation of secondary deviation caused by the existence of drift angle when the vehicle is rectified to the lane centerline, the heading angle controller is then designed in the control layer. The different torque distribution modes are divided according to the current vehicle speed, road adhesion coefficient and lateral acceleration in the execution layer, and the economic distribution, stability distribution, joint distribution are correspondingly executed among different torque distribution modes. Finally, Carsim and Matlab/Simulink are used for simulation verification.

关键词： execution Extension heading

A comprehensive study on the oxidation behavior and failure mechanism of(γ’+β)two-phase Ni-34Al-0.1Dy coating treated by laser shock processing

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Journal of Materials Science & Technology 2023年第31期162卷 131-144页

作者： Bangyang Zhou Qijie Zhou Jian He wei Wang hongbo Guo School of Materials Science and Engineering Beihang University(BUAA)Beijing 100191China Research Institute for Frontier Science Beihang University(BUAA)Beijing 100191China Key Laboratory of High-Temperature Structural Materials&Coatings Technology(Ministry of Industry and Information Technology) Beihang University(BUAA)Beijing 100191China State Key Laboratory of Long-Life High Temperature Materials Deyang 618000China Dongfang Electric Corporation Dongfang Turbine Co. LTDDeyang 618000China

Laser shock processing(LSP),as a novel surface modification technology,exhibits tremendous potential to improve the oxidation resistance of alloys.In this paper,(γ’+β)two-phase Ni-34Al-0.1Dy coatings were prepared by electron beam physical vapor deposition(EB-PVD)and then treated by LSP with different pulse energy(4 and 5 J).Their oxidation behavior(including isothermal oxidation and cyclic oxidation)at 1150°C was compared.In the isothermal oxidation case,the LSP-treated samples exhibited good ox-idation resistance due to high dislocation density and refined grains caused by the LSP.For the cyclic oxidation,however,the LSP-treated samples were subjected to undesirable thermally grown oxide(TGO)spallation.In the early oxidation stage(within 30 min),the residual compressive stress introduced by the LSP rapidly released,resulting in a severe plastic deformation at the coating/TGO interface.As a result,the mismatch between coating and TGO gave rise to the TGO spallation.With the increase in the oxida-tion time,work hardening,which continuously limited the synchronous deformation of the TGO/coating interface,became the dominant mechanism controlling the TGO spallation of 5 J-treated coatings.The continuous TGO spallation affected the Al supply and thus deteriorated the cyclic oxidation behavior.

关键词： Ni-34Al-0.1dy coating Laser shock processing Mechanical properties Oxidation Spallation

Probing the intriguing frictional behavior of hydrogels during alternative sliding velocity cycles

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摩擦:英文版 2023年第12期11卷 2329-2341页

作者： Yiming ZHAO Gang YI Jiuyu CUI Ziqian ZHAO Yonggan YAN Luxing wei Jinlong SHAO hongbo ZENG Jun HUANG Key Laboratory of High Efficiency and Clean Mechanical Manufacture of Ministry of Education National Demonstration Center for Experimental Mechanical Engineering EducationSchool of Mechanical EngineeringShandong UniversityJinan 250061China Shandong Key Laboratory of Advanced Organosilicon Materials and Technologies Zibo 256401China Department of Chemical and Materials Engineering University of AlbertaEdmontonAlberta T6G 1H9Canada Department of Periodontology School and Hospital of StomatologyCheeloo College of MedicineShandong University&Shandong Key Laboratory of Oral Tissue RegenerationJinan 250061China Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration Jinan 250012China

Understanding the friction behavior of hydrogels is critical for the long-term stability of hydrogelrelated bioengineering applications.Instead of maintaining a constant sliding velocity,the actual motion of bio-components(e.g.,articular cartilage and cornea)often changes abruptly.Therefore,it is important to study the frictional properties of hydrogels serving under various sliding velocities.In this work,an unexpected low friction regime(friction coefficientμ<10^(-4) at 1.05×10^(-3) rad/s)was observed when the polyacrylamide hydrogel was rotated against a glass substrate under alternative sliding velocity cycles.Interestingly,compared with the friction coefficients under constant sliding velocities,the measuredμdecreased significantly when the sliding velocity changed abruptly from high speeds(e.g.,105 rad/s)to low speeds(e.g.,1.05×10^(-3) rad/s).In addition,μexhibited a downswing trend at low speeds after experiencing more alternative sliding velocity cycles:the measuredμat 1.05 rad/s decreased from 2×10^(-2) to 3×10^(-3) after 10 friction cycles.It is found that the combined effect of hydration film and polymer network deformation determines the lubrication and drag reduction of hydrogels when the sliding velocity changes abruptly.The observed extremely low friction during alternative sliding velocity cycles can be applied to reduce friction at contacted interfaces.This work provides new insights into the fundamental understanding of the lubrication behaviors and mechanisms of hydrogels,with useful implications for the hydration lubrication related engineering applications such as artificial cartilage.

关键词： hydrogel friction alternative sliding velocity ultra-low friction coefficient drag reduction

Nitrogen removal and simultaneous nitrification and denitrification in a fluidized bed step-feed process

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Journal of Environmental Sciences 2012年第2期24卷 303-308页

作者： BingWang wei Wang Hongjun Han hongbo Hu Haifeng Zhuang State Key Laboratory of Urban Water Resources and Environment （SKLUWRE） Harbin Institute of Technology Harbin 150090 China Municipal ＆ Environmental Engineering College Shenyang Jianzhu University Shenyang 110168 China School of Civil and Hydraulic Engineering Hefei University of Technology Hefei 230009 China

For urban wastewater treatment,we conducted a novel four-stage step-feed wastewater treatment system combined with a fluidized bed laboratory experiment to investigate chemical oxygen demand（COD）,NH4＋-N,and total nitrogen（TN） removal performance.The removal rates of COD,NH4＋-N and TN were 88.2%,95.7%,and 86.4% with e？uent concentrations of COD,NH4＋-N and TN less than 50,8,and 10 mg/L,respectively.Biomass and bacterial activities were also measured,with results showing more nitrobacteria in the activated sludge than in the biofilm;however,bacterial activity of the biofilm biomass and the activated sludge were similar.Nitrogen concentrations during the process were also detected,with simultaneous nitrification and denitrification found to be obvious.

关键词： denitrification fluidized bed step-feed simultaneous nitrification and denitrification

Identification of the surgical indication line for the Denonvilliers’fascia and its anatomy in patients with rectal cancer

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Cancer Communications 2020年第1期40卷 25-31页

作者： Jianglong Huang Jing Liu Jiafeng Fang Zongheng Zeng Bo wei Tufeng Chen Hongbo Wei Department of Gastrointestinal Surgery The Third Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510630GuangdongP.R.China Department of Human Anatomy Histology and EmbryologyGuangdong Pharmaceutical UniversityGuangzhou 510006GuangdongP.R.China

Background:The high rate of urogenital dysfunction after traditional total mesorectal excision(TME)has caused doubts among scholars on the standard fashion of dissection.We have proposed the necessity to preserve the Denonvilliers’fascia in patients with rectal cancer.However,how to accurately locate the Denonvilliers’fascia is unclear.This study aimed to explore anatomical features of the Denonvilliers’fascia by comparing autopsy findings and observations of surgical videos so as to propose a dissection method for the preservation of pelvic autonomic nerves during rectal cancer surgery.Methods:Five adult male cadaver specimens were dissected,and surgical videos of 135 patients who underwent TME for mid-low rectal cancer between January 2009 and February 2019 were reviewed to identify and compare the structure of the Denonvilliers’fascia.Results:The monolayer structure of the Denonvilliers’fascia was observed in 5 male cadaver specimens,and it was located between the rectum,the bottom of the bladder,the seminal vesicles,the vas deferens,and the prostate.The Denonvilliers’fascia was originated from the rectovesical pouch(or rectum-uterus pouch),down to fuse caudally with the rectourethral muscle at the apex of the prostate,and fused to the lateral ligaments on both sides.The fascia was thinner on the midline with a thickness of 1.06±0.10 mm.The crown shape of the Denonvilliers’fascia was slightly triangular,with a height of approximately 5.42±0.16 cm at midline.Nerves were more densely distributed in front of the Denonvilliers’fascia than behind,especially on both sides of it.Under laparoscopic view,the Denonvilliers’fascia was originated at the lowest point of the rectovesical pouch(or rectum-uterus pouch),with a thickened white line which was a good mark for identifying the Denonvilliers’fascia.Conclusion:Identification of the surgical indication line for the Denonvilliers’fascia could help us identify the Denonvilliers’fascia,and it would improve our ability to protect the pelvic autonomic function of patients

关键词： cadaver dissection laparoscopic surgery pelvic autonomic nerve preservation rectal cancer the Denonvilliers’fascia total mesorectal excision

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进展期胃癌的外科治疗策略

中华胃肠外科杂志 2018年第10期21卷 1099-1102页

作者：魏波卫洪波中山大学附属第三医院胃肠外科广州510630

我国是胃癌大国，基于国内整体普查和诊疗现状，大多数患者确诊时已是进展期。目前，外科手术仍是进展期胃癌患者获得临床痊愈或改善生存状况的重要途径。对于可切除进展期胃癌的淋巴结清扫，D2根治术作为标准的进展期胃癌淋巴结清扫范... 详细信息

我国是胃癌大国，基于国内整体普查和诊疗现状，大多数患者确诊时已是进展期。目前，外科手术仍是进展期胃癌患者获得临床痊愈或改善生存状况的重要途径。对于可切除进展期胃癌的淋巴结清扫，D2根治术作为标准的进展期胃癌淋巴结清扫范围，逐渐被东亚国家和越来越多的西方国家接受。AJCC第8版TNM分期标准推荐，至少送检16枚淋巴结可带来较好的近期及远期生存，并指出获检30枚以上淋巴结能更好地评估预后。外科专家历经多年的研究探索发现，D1＋不适用于进展期胃癌；未侵及大弯侧的胃上部癌行全胃切除无需联合脾切除；不推荐切除网膜囊作为cT3或cT4a胃癌的标准治疗方式。对于腹腔镜手术在进展期胃癌治疗中的应用，日本JLSSG 0901和韩国KLASS-02的三期临床试验已在进行，旨在证实进展期胃癌腹腔镜手术远期生存不亚于传统开放手术。中国腹腔镜胃肠外科研究组的CLASS-01临床三期研究，对腹腔镜、开放远端胃切除术以及D2淋巴结清扫术对进展期胃癌的治疗进行了对比；其短期安全报告结果显示，腹腔镜技术具有良好的安全性和有效性，并且具有比较满意的肿瘤学疗效。随着转化治疗的发展，国外学者将Ⅳ期胃癌分为4类，即潜在可切除转移、边缘可切除转移、无法治愈和无法切除的转移、不可治愈的转移，并提出第2类、某些第3类和第4类患者适于转化治疗，手术的最佳时机通常是肿瘤对化疗的最佳反应时。此外，对于无法转化治疗或转化治疗无效的患者，在出现外科合并症如幽门狭窄或梗阻、肿瘤穿孔或无法缓解的大出血时，可选择姑息切除或短路手术。

关键词：胃肿瘤,进展期治疗外科手术

Hydrodearomatization Kinetics of Diesel Fraction and Catalyst Stacking Simulation

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China Petroleum Processing & Petrochemical Technology 2022年第3期24卷 105-116页

作者： wei Ye Sun Xinge LüHailong Jiang hongbo Chen Wenbin Qin Kang Li Mingfeng Nie Hong Petroleum Processing Institute East China University of Science and TechnologyShanghai 200237China SINOPEC Research Institute of Petroleum Processing Beijing 100083China

The kinetics of hydrodearomatization (HDA) is studied in an isothermal high-throughput reactor over three catalysts (CoMo, NiMo, and NiMoW) to produce clean diesel fuel according to China’s latest emission standards. The influences of reaction temperature, pressure, the ratio of H2 to oil, and space time were systematically investigated. By analyzing the reaction mechanism, a four-lump kinetic model considering the influence of competitive adsorption was proposed for the hydrodearomatization reaction, and the model parameters were optimized with good fitting. It was found that nitrogen compounds inhibited the hydrodearomatization reaction. The simulation of various catalyst stacking schemes based on the HDA kinetic model is close to the experimental data, proving the reliability of the model. The concentration of aromatic compounds of different loading sequences was predicted with the catalyst gradation model.

关键词： hydrodearomatization kinetic model diesel catalyst stacking