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Science China Chemistry 2008年第10期51卷 928-936页

作者： pang xuehui GUO WenJuan LI WeiHua XIE JianDong HOU BaoRong School of Chemistry and Chemical Engineering University of JinanJinan 250022China Institute of Oceanology Chinese Academy of SciencesQingdao 266071China Institute of Design and Research of Shandong Jianzhu University Jinan 250013China

The inhibiting effect and mechanism of 1-cyclopropyl-6-fluoro-1,4-dihydro -4-oxo-7-(1-piperazinyl) -3- quinoline carboxylicacid(ciprofloxacin), 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinoline carboxylic acid (norfloxacin) and (?)-(S)-9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7- oxo-7 H-pyrido(1,2,3-de)-1,4- benzoxazine-6 carboxylic acid (ofloxacin) on the corrosion of mild steel in 1 mol/L HCl have been studied using electrochemical method, quantum chemical method and SEM at 303 K. The potentiodynamic results showed that these compounds suppressed both cathodic and an-odic processes of mild steel corrosion in 1 mol/L HCl. The impedance spectroscopy showed that Rp values increased, and Cdl values decreased with the rising of the working concentration. Quantum chemical calculation showed that there was a positive correlation between some inhibitors structure properties and the inhibitory efficiency. The inhibitors function through adsorption followed Langmuir isotherm, and chemisorption made more contribution to the adsorption of the inhibitors on the steel surface compared with physical adsorption. SEM analysis suggested that the metal had been protected from aggressive corrosion because of the addition of the inhibitors.

关键词： inhibition mild steel polarization electrochemical impedance spectroscopy SEM

Corrosion inhibition and mechanism of mild steel in hydrochloric acid by ceftriaxone and amoxicillin

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Science China Chemistry 2011年第9期54卷 1529-1536页

作者： pang xuehui GONG Min ZHANG YuXuan WEI Qin HOU BaoRong Institute of Oceanology Chinese Academy of sciences Qingdao 266071 China College of Materials and Chemical Engineering Sichuan University of Science & Engineering Zigong 643000 China School of Chemistry and Engineering University of Jinan Jinan 250022 China

Corrosion inhibition of mild steel in 1 mol/L HC1 by amoxicillin and ceftriaxone in the concentration range of 1.00×10^-5-1.00×10^-2 mol/L has been studied using weight loss, electrochemical potentiodynamic polarization, electrochemical impedance spectroscopy （EIS）, scanning electron microscopy （SEM） and quantum chemistry tests at 298 K. The weight loss experiment showed that the inhibition efficiency increased with amoxicillin and ceftriaxone concentrations to attain the maximums of 80.3% and 94.1%, respectively at 1.00×10^-2 mol/L. Potentiodynamic polarization indicated that amoxicillin and ceftriaxone acted as mixed-type inhibitors but mainly inhibited cathode hydrogen evolution reaction for mild steel in 1 mol/L HC1. The electrochemical impedance spectroscopy （EIS） demonstrated the inhibitors covered the active points of metal surface to inhibit corrosion. The absorption of both inhibitors on the mild steel surface was found to follow Langmuir adsorption isothermal and dominantly involve chemical adsorption at 298 K. Scanning electron microscopy （SEM） confirmed both of the inhibitors played a significant protective effect in mild steel corrosion in 1 mol/L HC1. The relationship between the inhibition properties and molecular structure had been discussed by quantum chemistry calculation. All the experimental results concluded that both amoxicillin and ceftriaxone acted as good corrosion inhibitors and their inhibition efficiency was in the order of ceftriaxone 〉 amoxicillin.

关键词： corrosion mild steel acid weight loss potentiodynamic polarization curve EIS SEM quantum chemistry

Biomineralization of organic matter in cobalt-rich crusts from the Marcus–Wake Seamounts of the western Pacific Ocean

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Acta Oceanologica Sinica 2014年第12期33卷 67-74页

作者： ZHAO Jun ZHANG Haisheng WU Guanghai LU Bing PULYAEVA Irina A ZHANG Haifeng pang xuehui Key Laboratory of Marine Ecosystem and Biogeochemistry Second Institute of Oceanography State Oceanic Administration State Scientific Centre Yuzhmorgeologia Gelendzhik 353461 Russia School of Chemistry and Engineering University of Jinan

Organic matter in cobalt-rich crust （CRC） from the Marcus-Wake Seamounts of the western Pacific Ocean, Sample CM1D03, has been analyzed to understand the source, geochemistry and mineralization of organic matter, and the mineralization environment. Biomarkers, includingn-alkanes, isoprenoids, terpanes and sterols, have been detected in various layers of the CRC sample, using gas chromatography （GC） and gas chromatography-mass spectrometry （GC-MS）. The content of organic carbon （OC） and its stable isotope （δ13C）, and the combined features of the biomarkers show that the mineralized organic matter in CM1D03 CRC was mainly derived from microorganisms and lower plankton （e.g., bacteria and algae, respectively） from marine surface water, with some terrestrial higher plant components. The ratio of chloroform bitu-men ＂A＂： OC was high in the CRC, between 10.51 and 20.66, showing significant migration characteristics of n-alkanes. Four mineralization categories of organic matter were recognized based on GC chromatograms ofn-alkane molecules：（1） primitive type （bacteria and algae）, which is characterized by moderately mature ofn-alkanes preserving the original characteristics of the organic matter from microorganisms and lower plankton; （2） microbial degradation type, which is characterized by low contents ofn-alkanes and rising baseline in the chromatogram, with the ＂bulge＂ being the products of organic matter by biodegradation; （3） organic matter migration type, which is characterized by low carbon number ofn-alkanes withnC18 as the main peak carbon, without odd even predominance, and low concentrations of isoprenoids and hydro-carbons with high carbon number; and （4） organic matter hydrothermal type, which is characterized by relatively low concentration of small molecular weightn-alkanes, pristane, and phytane, accompanied by higher concentration ofn-alkanes with carbon number greater thannC18. This study shows that biomarkers can record controlling factors of mineraliz

关键词： ubiomineralization cobalt-rich crust biomarker Marcus-Wake Seamounts

Adsorption of CO molecules on Rh low index and (331)stepped surfaces

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Chinese Science Bulletin 2004年第10期49卷 1012-1019页

作者： WANG Zexin pang xuehui WANG Rui Chemistry Department, Shandong Normal University, Jinan 250014,China Correspondence should be addressed to Wang Zexin Chemistry Department Shandong Normal University Jinan China

The 5-parameter Morse potential (for short5-MP) of the interaction between C, O atom and Rh surfaceand the extended LEPS potential have been constructed, andthe adsorption and diffusion of CO molecules on Rh low in-dex surfaces and open rough Rh(331) stepped surface areinvestigated. This work puts forward the concept of vibra-tion dactylogram property for molecular adsorption *** calculation results and the analysis of vibration dactylo-gram show that there exists the commonness in the adsorp-tion on Rh low index surfaces and Rh(331) stepped surface: with the increasing coverage, the top, bridge sites are ad-sorbed in perpendicularly in sequence, and the top sites arethe steady adsorption sites and the bridge sites are the *** (100) surface, CO molecules obtain the eigenvibration of2009, 1946 cm^-1 on the top and bridge sites respectively andthe difference between the binding energy of above two sitesis 0.09 eV; on (110) surface, CO molecules obtain the eigen-vibration of 2019, 1961 cm^-1 respectively; on (111) surface,CO molecules on the top. bridge and hollow sites produce theeigenvibration of 2000, 1912, 1894 cm^-1 respectively, thebinding energies of the three sites decrease in turn and thediscrepancy between the top and bridge sites is 0.03 eV; on (331) surface, top and bridge sites between two equivalenttop sites are adsorbed in, and then obtain the eigenvibrationof 2018, 1987 cm^-1; 1969, 1927 cm^-1 respectively.

关键词：一氧化碳铑 5-MP 扩展LEPS电势表面吸附陆地指纹本征振动

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高温弹体的精度综合测量系统

机械工程学报 2008年第10期44卷 145-148,153页

作者：庞学慧张治民中北大学机械工程与自动化学院

针对挤压成形的高温弹体壁厚差与形位误差在线测量难题,提出一种新的测量原理,成功研制专用弹体几何精度测量系统。介绍系统的工作原理、基本构成、软硬件系统,以及数据处理和弹体热变形补偿的方法,并给出测量实例。实际使用表明,该系... 详细信息

针对挤压成形的高温弹体壁厚差与形位误差在线测量难题,提出一种新的测量原理,成功研制专用弹体几何精度测量系统。介绍系统的工作原理、基本构成、软硬件系统,以及数据处理和弹体热变形补偿的方法,并给出测量实例。实际使用表明,该系统能够实现对弹体准确、快速的自动测量,可以解决弹体自动化生产的一项难题。

关键词：弹体几何精度在线测量热变形补偿

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颗粒阻尼铣刀减振分析与试验研究

制造技术与机床 2016年第6期 89-93页

作者：张恒明庞学慧中北大学机械与动力工程学院山西太原030051

研究了多种阻尼颗粒在不同填充参数下对颗粒阻尼铣刀减振效果的影响。对颗粒阻尼铣刀进行锤击实验以测得刀杆阻尼比,进行铣削实验以测得工件表面粗糙度。比较了颗粒粒径、密度、填充率对减振效果的影响,发现了较优的填充颗粒参数。实验... 详细信息

研究了多种阻尼颗粒在不同填充参数下对颗粒阻尼铣刀减振效果的影响。对颗粒阻尼铣刀进行锤击实验以测得刀杆阻尼比,进行铣削实验以测得工件表面粗糙度。比较了颗粒粒径、密度、填充率对减振效果的影响,发现了较优的填充颗粒参数。实验结果表明:填充颗粒直径越小,密度越大、减振效果越好,当填充率为70%时,减振效果最佳;选取合理填充颗粒参数时,刀杆阻尼比最高达到4.35%,铣削后的工件表面粗糙度值最低为1.392μm,相比于实心铣刀降低了50.09%;球粉混合填充模型有待进一步研究。

关键词：颗粒阻尼铣刀阻尼比表面粗糙度

吡哌酸、左氧氟沙星及环丙沙星在0．5mol／L H2SO4中对碳钢的缓蚀性能与机理研究

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化学学报 2011年第4期69卷 483-491页

作者：庞雪辉张玉璇张洁解建东侯保荣济南大学化学化工学院济南250022 北京林业大学环境科学与工程学院北京100083 山东建筑大学济南250013 中国科学院海洋研究所青岛266071

利用失重实验、动电位极化曲线测试、交流阻抗测试(EIS)及扫描电子显微镜(SEM)方法对吡哌酸(8-乙基-5-氧代-5,8-二氢-2-(1-哌嗪基)吡啶并[2,3-d]嘧啶-6-羧酸)、左氧氟沙星[(±)-9-氟-2,3-二氢-3-甲基-10-(4-甲基-1-哌嗪基)-7-氧代-7H-... 详细信息

利用失重实验、动电位极化曲线测试、交流阻抗测试(EIS)及扫描电子显微镜(SEM)方法对吡哌酸(8-乙基-5-氧代-5,8-二氢-2-(1-哌嗪基)吡啶并[2,3-d]嘧啶-6-羧酸)、左氧氟沙星[(±)-9-氟-2,3-二氢-3-甲基-10-(4-甲基-1-哌嗪基)-7-氧代-7H-吡啶并[1,2,3-de][1,4]苯并恶嗪-6-羧酸]及环丙沙星[l-环丙基-6-氟-1,4-二氢-4-氧代-7-(1-哌嗪基)-3-喹啉羧酸]在303 K时0.5 mol/L H2SO4中对碳钢的缓蚀性能、作用机理进行研究.失重实验得出,303 K时试样浸泡在0.5 mol/L H2SO4溶液中的腐蚀速度随缓蚀剂的浓度增大而减小,同时三种缓蚀剂的缓蚀效率显著增大.电化学测试表明缓蚀剂分子对阴阳极反应均有抑制作用,但对阴极的抑制作用更加明显,其抑制作用与缓蚀剂在金属表面的覆盖有关.303 K时缓蚀剂在金属表面的吸附行为符合Langmuir等温线,且作用过程物理、化学吸附兼有.扫描电子显微镜观察结果表明,添加三种缓蚀剂对碳钢表面的腐蚀起到了显著的保护作用.同种条件下的测试结果表明,环丙沙星缓蚀性能最强.

关键词：缓蚀失重动电位极化交流阻抗扫描电子显微镜吸附

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切削用量对车削42CrMo钢切削力的影响

机床与液压 2016年第3期44卷 163-165页

作者：李琴梁军华庞学慧山西机电职业技术学院山西长治046011 四川工程职业技术学院四川德阳618000 中北大学山西太原030051

在单因素条件下通过改变切削用量车削42CrMo钢试验,得出了切削用量的改变对主切削力、进给力、背向力与总切削力的影响规律,分析了切削用量的改变导致切削力变化的原因,提供了车削42CrMo钢半精加工阶段的参考切削用量。结果表明:背吃刀... 详细信息

在单因素条件下通过改变切削用量车削42CrMo钢试验,得出了切削用量的改变对主切削力、进给力、背向力与总切削力的影响规律,分析了切削用量的改变导致切削力变化的原因,提供了车削42CrMo钢半精加工阶段的参考切削用量。结果表明:背吃刀量和进给量的改变对主切削力的影响较大,而切削速度的改变对主切削力影响较小;总切削力的变化规律与主切削力相似,背吃刀量对进给力的影响较大。

关键词：车削 42CrMo 切削力切削用量

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水基润滑剂在温挤成形中的应用

锻压技术 2015年第1期40卷 104-107页

作者：徐健庞学慧张治民中北大学材料科学与工程学院山西太原030051

温挤成形工艺在生产中应用广泛,虽然通过对模具材料的热处理和表面处理技术,提高了模具自身性能,但由于模具长时间处于高温、高压状态,使得模具容易产生磨损和回火现象,严重影响模具的使用寿命。为了解决这个问题,具体分析了几种常用润... 详细信息

温挤成形工艺在生产中应用广泛,虽然通过对模具材料的热处理和表面处理技术,提高了模具自身性能,但由于模具长时间处于高温、高压状态,使得模具容易产生磨损和回火现象,严重影响模具的使用寿命。为了解决这个问题,具体分析了几种常用润滑材料的物理特性和润滑性能,针对不同类型润滑剂在不同环境条件下的润滑效果和冷却效果进行了对比研究,得到了水基润滑剂的适用温度范围。其中,水基石墨润滑剂在300~800℃挤压温度范围内,润滑性能可靠,可以使模具表面冷却,实现延长模具的使用寿命的设计构想。

关键词：温挤成形水基润滑剂润滑效果使用寿命

喹诺酮药品对Q235钢在HCl溶液中缓蚀性能的影响

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中国腐蚀与防护学报 2008年第3期28卷 166-172页

作者：庞雪辉李伟华侯保荣于志刚中国海洋大学化学化工学院青岛266100 中国科学院海洋研究所青岛266071

用失重法、极化曲线和交流阻抗等方法研究了喹诺酮类药品(诺氟沙星、氧氟沙星)对在1 mol/L HCl溶液中的Q235钢的缓蚀性能和作用机理的影响。结果表明,所研究的两种喹诺酮类药品均具有较好的缓蚀性能,二者在有效浓度为3.5 mmol/L时对碳... 详细信息

用失重法、极化曲线和交流阻抗等方法研究了喹诺酮类药品(诺氟沙星、氧氟沙星)对在1 mol/L HCl溶液中的Q235钢的缓蚀性能和作用机理的影响。结果表明,所研究的两种喹诺酮类药品均具有较好的缓蚀性能,二者在有效浓度为3.5 mmol/L时对碳钢的缓蚀效率分别为95%、92%,二者均为阳极抑制为主的的混合抑制型缓蚀剂。同时,还考察了温度对两种缓蚀剂的缓蚀性能的影响,结果是温度的升高不利于其缓蚀作用的发挥。

关键词：喹诺酮腐蚀交流阻抗极化曲线