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An ecofriendly approach for corrosion control of 6061 Al-15%(v)SiC(P)composite and its base alloy

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Chinese Journal of Chemical Engineering 2017年第3期25卷 363-372页

作者： Charitha B.P. Padmalatha rao Department of chemistry Manipal Institute of TechnologyManipalUdupiKamatakaIndia

Corrosion inhibition characteristics of bio polymer dextran was studied for the corrosion control of 6061 Al-15%_((v)) SiC_((P)) composite and its base alloy in 1 mol·l^(-1) HCl. Standard electrochemical techniques such as potentiodynamic polarization(PDP) measurements and electrochemical impedance spectroscopy(EIS) method were adopted for corrosion rate measurement. Surface morphology was studied by scanning electron microscopy(SEM) and elemental mapping was done by energy dispersive X-ray(EDX) analysis. Suitable mechanism was proposed for corrosion and inhibition process. Results indicated that dextran acts as an excellent anticorrosive agent for the corrosion control of 6061 Al-15%_((v)) SiC_((P)) composite, with maximum inhibition efficiency of 91% for the concentration of 0.4 g·l^(-1) at 303 K. Dextran acted as a mixed type of inhibitor, and got physically adsorbed both on composite and base alloy by obeying l.ngmuir adsorption isotherm. Dextran is proved to be a green inhibitor with environmental and economic benefits.

关键词： 6061 Al-15%(v) SiC(p) composite Green inhibitor Biopolymer Electrochemical studies SEM–EDX

控氮型不锈钢316lN在含氯介质中的点蚀行为

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机械科学与技术 2024年第6期43卷 1084-1091页

作者：华晓春黄国辉左竞成赵丽饶思贤安徽工业大学机械工程学院安徽马鞍山243032 合肥通用机械研究院国家压力容器与管道安全工程技术中心合肥230031

针对N元素对奥氏体不锈钢抗点蚀能力的影响与其机理尚不明确的现状,以控氮型不锈钢316lN为研究对象,对其进行力学性能测试和电化学阻抗谱等电化学测试。结果表明316lN在室温下的力学性能及抗腐蚀性能均比不含氮的316l优越,但随着温度与... 详细信息

针对N元素对奥氏体不锈钢抗点蚀能力的影响与其机理尚不明确的现状,以控氮型不锈钢316lN为研究对象,对其进行力学性能测试和电化学阻抗谱等电化学测试。结果表明316lN在室温下的力学性能及抗腐蚀性能均比不含氮的316l优越,但随着温度与介质浓度的提升,316lN的抗腐蚀性能存在明显的劣化;在室温和低介质浓度下,316lN的钝化膜阻抗普遍高于316l,显示在N元素和Cr、Mo等合金元素的协同下,316lN的表层钝化膜稳定性高于316l;同时N元素的转化产物NH_(4)^(+)或NO_(3)^(-)可有效抑制点蚀内部二次点蚀坑的形成,避免点蚀坑向纵深快速扩展。

关键词： 316lN不锈钢 N元素点蚀电化学阻抗谱

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超声辅助提取油莎豆油的工艺优化及品质分析

食品工业科技 2024年第10期45卷 207-216页

作者：权煜刘学强赵丹丹饶欢吴彤娇郝建雄河北科技大学食品与生物学院河北石家庄050000

为提高油莎豆油的得率且保证成品品质,本研究采用超声辅助正己烷法对油莎豆油的提取工艺进行响应面试验优化,确定最优提取条件后对油莎豆油品质进行分析。在油的品质研究中,采用25℃(常温)、47℃(超声辅助提取最佳温度)、60℃(高温)三... 详细信息

为提高油莎豆油的得率且保证成品品质,本研究采用超声辅助正己烷法对油莎豆油的提取工艺进行响应面试验优化,确定最优提取条件后对油莎豆油品质进行分析。在油的品质研究中,采用25℃(常温)、47℃(超声辅助提取最佳温度)、60℃(高温)三个温度对比超声作用对油样中总酚含量、总黄酮含量、1, 1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除率、脂肪酸组成及含量的影响。结果表明:脱皮油莎豆研磨后在料液比1:15 (g/ml)、超声时间20 min、超声温度47℃、粉碎粒度70目时,油莎豆油的得率为25.01%±0.03%,油样为黄橙色微浊状态,具有豆类特有的香气。油莎豆油对DPPH自由基有一定的清除作用,超声可更好地溶出油莎豆中的营养物质,但对油莎豆中黄酮类物质的破坏效应相对较大,酚酸类物质在高温时含量显著(P<0.05)下降。在25~60℃间超声作用和温度的变化对脂肪酸的种类和含量的影响不大,油酸(C18:1)含量最高,约为73.81%~74.00%。本试验结果可以为油莎豆油脂的开发利用提供一定基础和理论依据。

关键词：油莎豆油超声辅助提取工艺优化抗氧化活性气相色谱黄酮多酚脂肪酸组成

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多发性硬化与吉兰-巴雷综合征脑脊液实验室检测结果的比较分析

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中华检验医学杂志 2024年第2期47卷 136-141页

作者：马瑞敏饶昕怡陈宇欣吕虹张国军首都医科大学附属北京天坛医院检验科北京100070 首都医科大学第五临床医学院北京100070 首都医科大学临床检验诊断学系北京100070

目的比较多发性硬化(MS)和吉兰-巴雷综合征(GBS)脑脊液检测结果的特点,为2种神经系统脱髓鞘疾病的鉴别诊断提供依据。方法病例分析。以2020年1月至2023年8月在首都医科大学附属北京天坛医院就诊的患者为研究对象,其中MS患者70例[男性19... 详细信息

目的比较多发性硬化(MS)和吉兰-巴雷综合征(GBS)脑脊液检测结果的特点,为2种神经系统脱髓鞘疾病的鉴别诊断提供依据。方法病例分析。以2020年1月至2023年8月在首都医科大学附属北京天坛医院就诊的患者为研究对象,其中MS患者70例[男性19例,女性51例,年龄34(28,44)岁],GBS患者70例[男性44例,女性26例,年龄50(36,61)岁]。对2组患者进行寡克隆区带电泳及免疫球蛋白G指数(IgG I)检测,同时检测脑脊液常规、脑脊液生化(葡萄糖、氯、蛋白)、乳酸、白介素-6(Il-6)、白介素-8(Il-8)、肿瘤坏死因子-α(TNF-α)、单纯疱疹病毒(HSV)抗体、巨细胞病毒(CMV)抗体、风疹病毒(RV)抗体、弓形虫(TOX)抗体、EB病毒(EBV)抗体、柯萨奇病毒(COX)抗体。计数资料比较采用χ^(2)检验;计量资料不符合正态分布,比较采用Mann-Whitney U检验。结果MS患者和GBS患者寡克隆区带电泳的阳性率分别为80.00%(56/70)和4.29%(3/70),MS患者阳性率高于GBS患者(χ^(2)=82.289,Pl]、氯[127(125,128)mmol/l]水平均高于GBS患者[3.50(2.00,7.00)个/μl,126(124,128)mmol/l](U=-2.245,Pl]、葡萄糖[3.59(3.36,3.88)mmol/l]和乳酸[1.55(1.40,1.73)mmol/l]水平低于GBS患者[76.71(43.78,138.30)mg/l,3.97(3.55,4.54)mmol/l,1.80(1.60,2.00)mmol/l](U=-6.747,Pl-6[3.36(2.34,5.02)pg/ml]、Il-8[55.40(46.75,66.40)pg/ml]和TNF-α[5.63(4.25,6.63)pg/ml]水平均低于GBS患者[6.12(3.61,11.73)pg/ml,120.00(74.90,187.80)pg/ml,6.57(5.25,8.03)pg/ml](U=-3.463,P<0.05;U=-5.225,P<0.001;U=-2.785,P<0.05)。MS患者脑脊液中CMV IgG、TOX IgG、EBVCA-IgG阳性率分别为36.36%(24/66)、0、0,GBS患者脑脊液中CMV IgG、TOX IgG、EBVCA-IgG阳性率分别为85.71%(54/63)、30.16%(19/63)、19.05%(12/63),MS患者脑脊液中CMV IgG、TOX IgG、EBVCA-IgG阳性率低于GBS患者(χ^(2)=32.839,P<0.001;χ^(2)=23.343,P<0.001;χ^(2)=13.861,P<0.001)。结论MS患者主要表现为脑脊液寡克隆区带电泳阳性率较高。GBS患者脑脊液蛋白水平升高而白细胞数升高不明显,表现为脑脊液蛋白-细胞分离现象,同时鞘内免疫、炎症相关指标水平升高,病原体抗体阳性率较高。

关键词：多发性硬化吉兰-巴雷综合征脱髓鞘疾病脑脊髓液

Crystal structures and biochemical studies of human lysophosphatidic acid phosphatase type 6

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Protein & Cell 2013年第7期4卷 548-561页

作者： Jun li Yu Dong Xingru lü lu Wang Wei Peng Xuejun C.Zhang Zihe rao National laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Structure Biology laboratory Tsinghua UniversityBeijing 100084China Tianjin Key laboratory of Protein Science College of Life SciencesNankai UniversityTianjin 300071China

lysophosphatidic acid(lPA)is an important bioac-tive phospholipid involved in cell signal.ng through G-protein-coupled receptors *** is also involved in balancing the lipid composition inside the cell,and modulates the function of lipid rafts as an intermediate in phospholipid *** of its involvement in these important processes,lPA degradation needs to be regulated as precisely as its ***-tidic acid phosphatase type 6(ACP6)is an lPA-specifi c acid phosphatase that hydrolyzes lPA to monoacylglyc-erol(MAG)and ***,we report three crystal structures of human ACP6 in complex with malonate,l-(+)-tartrate and tris,*** analyses revealed that ACP6 possesses a highly conserved Rossmann-fold-like body domain as well as a less conserved cap *** vast hydrophobic substrate-binding pocket,which is located between those two domains,is suitable for ac-commodating lPA,and its shape is different from that of other histidine acid phosphatases,a fact that is consistent with the observed difference in substrate *** analysis of the binding of three molecules in the active site reveals the involvement of six conserved and crucial residues in binding of the lPA phosphate group and its *** structure also indicates a water-supplying channel for substrate *** structural data are consistent with the fact that the enzyme is active as a *** combination with additional mutagenesis and enzyme activity studies,our structural data provide important insights into substrate recognition and the mechanism for catalytic activity of ACP6.

关键词： lysophosphatidic acid histidine acid phos-phatase crystal structure

Geochemical evidences of trace metal anomalies for finding hydrocarbon microseepage in the petroliferous regions of the Tatipaka and Pasarlapudi areas of Krishna Godavari Basin,India

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Petroleum Science 2013年第1期10卷 19-29页

作者： Rasheed M A lakshmi M rao P l S Kalpana M S Dayal A M Patil D J Microbiology laboratory Petroleum Geochemistry Group National Geophysical Research Institute (Council of Scientific and Industrial Research)

The l.ng-term seepage of hydrocarbons, either as macroseepage or microseepage, can set up near-surface oxidation reduction zones that favor the development of a diverse array of chemical and mineralogical changes. The bacterial oxidation of light hydrocarbons can directly or indirectly bring about significant changes in the values of pH and Eh of the surrounding environment, thereby also changing the stability fields of the different mineral species present in that environment. The paper reports the role of hydrocarbon microseepage in surface alterations of trace metal concentrations. In this study trace metal alterations were mapped that appear to be associated with hydrocarbon microseepages in the oil/ gas fields. A total of 50 soil samples were collected near oil and gas fields of the Tatipaka and Pasarlapudi areas of the Krishna Godavari Basin, Andhra Pradesh. The soil samples were collected from a depth of 2-2.5 m. The paper reports the chemical alterations associated with trace metals in soils that are related to hydrocarbon microseepages above some of the major oil and gas fields of this petroliferous region. Trace metals, such as scandium （Sc）, vanadium （V）, chromium （Cr）, cobalt （Co）, nickel （Ni）, copper （Cu）, zinc （Zn）, barium （Ba） and strontium （Sr）, in soil samples were analyzed using inductively coupled plasma- mass spectrometry （ICP-MS）. The concentrations of Sc （8 to 40 mg/kg）, V （197 to 489 mg/kg）, Cr （106 to 287 mg/kg）, Co （31 to 52 mg/kg）, Ni （65 to 110 mg/kg）, Cu （88 to 131 mg/kg）, Zn （88 to 471 mg/kg）, Ba （263 to 3,091 mg/kg） and Sr （119 to 218 mg/kg） were obtained. It was observed that the concentrations of trace elements were tremendously increased when they were compared with their normal concentrations in soils. The analysis of adsorbed soil gas showed the presence of high concentrations of YC2＋（C2H6, C3H8 and n-C4H10） ranging from 7 to 222 μg/kg respectively. Integrated studies of trace elements over adsorbed light gaseous hydrocarbons （2C2

关键词： Hydrocarbons microseepage trace metal alterations adsorbed soil gas Krishna Godavari Basin

Simultaneous determination of pioglitazone and candesartan in human plasma by lC-MS/MS and its application to a human pharmacokinetic study

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Journal of Pharmaceutical Analysis 2012年第3期2卷 167-173页

作者： Vijaya Kumari Karra Nageswara rao Pilli Jaswanth Kumar Inamadugu J.V.l.N.Seshagiri rao University College of Pharmaceutical Sciences Jawaharlal Nehru Technological UniversityKukatpallyHyderabad-500085India Analytical and Environmental Chemistry Division Department of ChemistrySri Venkateswara UniversityTirupati-517502India College of Pharmaceutical Sciences Andhra UniversityVisakhapatnam-530003India

A simple and rapid liquid chromatography-tandem mass spectrometric(lC-MS/MS) assay method has been developed and fully validated for simultaneous quantification of pioglitazone and candesartan in human *** was used as an internal *** analytes were extracted from human plasma samples by solid-phase extraction technique using a Strata-X 33 mm polymeric *** reconstituted samples were chromatographed on a C18 column by using a 80:20(v/v) mixture of acetonitrile and 0.1% formic acid as the mobile phase at a flow rate of 0.8 ml/*** calibration curves obtained were linear(rZ0.99) over the concentration range of 15-3000 ng/ml for pioglitazone and 5-608 ng/ml for *** results of the intra-and inter-day precision and accuracy studies were well within the acceptable limits.A run time of 2.7 min for each sample made it possible to analyze more than 300 plasma samples per *** proposed method was found to be applicable to clinical studies.

关键词： Pioglitazone Candesartan Human plasma Solid-phase extraction lC-MS/MS Pharmacokinetics

Soil Enzyme Activities and Organic Matter Composition Affected by 26 Years of Continuous Cropping

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Pedosphere 2016年第5期26卷 618-625页

作者： Fugen DOU Alan l.WRIGHT rao S.MYlAVARAPU JIAng Xianjun John E.MATOCHA Texas A&M Agrilife Research Center at Beaumont BeaumontTX 77713(USA) University of Florida Indian River Research&Education CenterFt.PierceFL 34945(USA) University of Florida Soil&Water Science Dept.GainesvilleFL 32611(USA) Southwest University College of Resources and EnvironmentChongqing(China) Texas A&M University Agricultural Research and Extension CenterCorpus ChristiTX 78406(USA)

The study was to determine the l.ng-term effects of subtropical monoculture and rotational cropping systems and fertilization on soil enzyme activities and soil C, N, and P levels. Cropping systems included continuous sorghum(Sorghum bicolor l.), cotton(Gossypium hirsutum l.), corn(Zea mays l.), and cotton/sorghum rotations after 26 years of treatment imposition. Soil under continuous sorghum and continuous corn had 15% and 11%, respectively, greater C concentrations than soil under continuous *** C was 10% higher at 0–7.5 cm than at 7.5–15 cm. Total N followed similar trends with soil depth as organic C. Continuous sorghum had 19% higher total N than other crop species and rotations. With fertilization, continuous cotton had the highest total P at 0–7.5 cm and sorghum had the highest at 7.5–15 cm. Soil total P was 14% higher at 0–7.5 than at 7.5–15 cm, and fertilization increased 15% total P compared to unfertilized soil. Arylsulfatase, alkaline phosphatase, and β-d-glucosidase activity were the highest for sorghum and the lowest for cotton. Rotation increased enzyme activities compared to continuous cotton but not for continuous sorghum. Of all crop species and rotations, continuous cotton generally showed the lowest levels of organic matter and enzyme activities after 26 years. Fertilization significantly increased the yields for all cropping systems, but rotation had no significant effect on either sorghum or cotton lint yield compared to each crop grown in monoculture. l.ng-term cropping did not increase soil organic matter levels beyond short-term gains, indicating the difficulty in promoting C sequestration in subtropical soils.

关键词： C sequestration fertilization monoculture rotation subtropical soil

lncRNAuc.48+对CGRP介导的三叉神经痛的作用

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中国药理学通报 2024年第10期40卷 1866-1871页

作者：谭梦霞吴饶平张爱霞高云熊伟南昌大学基础医学院生理学教研室江西南昌330006 江西卫生职业学院江西南昌330052 南昌医学院江西南昌330052 南昌大学附属口腔医院江西南昌330019

目的探究长链非编码核糖核酸uc.48+(l.ng non-coding RNA,lncRNA uc.48+)如何影响三叉神经痛(trigeminal neuralgia,TN)大鼠三叉神经节(trigeminal ganglion,TG)中降钙素基因相关肽(calcitonin gene related peptide,CGRP)以及其潜在的作用机制。方法慢性压迫性损伤大鼠眶下神经(chronic compression injury to the infraorbital nerve,CCI-ION)建立大鼠TN动物模型。成模后,经眶下孔局部注射uc.48+小干扰敲低lncRNAuc.48+,以及向正常大鼠转染uc.48+质粒过表达lncRNAuc.48+。通过行为学来观察各组大鼠面部机械痛阈值(mechanical pain threshold,MWT),结合qPCR、蛋白印迹等方法观察大鼠TG中CGRP的含量及变化。ElISA法观察1l-1β的变动状况。结果接受uc.48+小干扰处理的TN大鼠机械痛敏阈值明显上升;TG中CGRP的蛋白、mRNA水平明显下降(Pl-1β的水平也降低(Pl-1β的水平明显增加(P<0.01)。结论TN大鼠敲除uc.48+显著减轻疼痛,而过表达uc.48+则加剧了TN的疼痛传导。uc.48+小干扰对TN有一定的抑制作用,该机制可能是通过减少神经病理痛大鼠TG中CGRP的表达,抑制初级感觉神经节对三叉神经病理痛信息的传播,进而减轻三叉神经病理痛对机械性疼痛的敏感性。

关键词：长链非编码核糖核酸uc.48+ 三叉神经痛降钙素基因相关肽三叉神经节小干扰过表达