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Effect of HCO_3^- concentration on CO_2 corrosion in oil and gas fields

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Journal of University of Science and Technology Beijing 2006年第1期13卷 44-49页

作者： guoan Zhang Minxu Lu Chengwen Chai yinshun Wu Corrosion and Protection Center University of Science and Technology Beijing Beijing 100083 China

The effect of HCO3^- concentration on CO2 corrosion was investigated by polarization measurement of potentiodynamic scans and weight-loss method, Under the conditions of high pressure and high temperature, the corrosion rate of steel X65 decreased with the increase of HCO3^- concentration, while pH of solution increased. SEM, EDS, and XRD results of the corrosion scales indir cated that the typical FeCO3 crystallite was found at low HCO3^- concentration but Ca（Fe,Mg）（CO3）2 was found at high HCO3^- con- centration. Ca^2＋ and Mg^2＋ are precipitated preferential to Fe^2＋ at high pH value. Potentiodynamic polarization curves showed that the cathodic current density decreases with the increase of HCO3^- concentration at low HCO3^- concentration. When the HCO3^- concentration reaches 0.126 mol/L, increasing HCO3^- concentration promotes cathodic reactions. Anodic behavior is an active process at low HCO3^- concentration and the anodic current density decreases with the increase of HCO3^- concentration. An evident active-passive behavior is exhibited in anodic process at 0.126 mol/L HCO3^-.

关键词： oil and gas fields carbon dioxide corrosion bicarbonate concentration polarization curves

无透镜编码叠层显微成像原理及研究进展(特邀)

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激光与光电子学进展 2024年第6期61卷 54-71页

作者：郭成飞李婧妍江劭玮邵晓鹏郑国安西安电子科技大学杭州研究院浙江杭州311231 西安电子科技大学光电工程学院陕西西安710071 杭州电子科技大学通信工程学院浙江杭州310018 康涅狄格大学生物医学工程系美国斯托斯06269

叠层成像技术是近年来发展快速的相干衍射成像方法,目前已经成为世界上大多数X射线同步加速器和国家实验室不可或缺的成像工具。光学叠层成像是叠层成像技术在可见光波段的应用,分为基于透镜的傅里叶叠层成像与基于无透镜的编码叠层成... 详细信息

叠层成像技术是近年来发展快速的相干衍射成像方法,目前已经成为世界上大多数X射线同步加速器和国家实验室不可或缺的成像工具。光学叠层成像是叠层成像技术在可见光波段的应用,分为基于透镜的傅里叶叠层成像与基于无透镜的编码叠层成像。编码叠层成像作为一种新型无透镜片上显微成像技术,具有大视场、高分辨率、无像差、无标记、便携式,以及缓变相位成像等诸多技术优点。本文介绍无透镜编码叠层显微成像的基本原理及最新研究进展,分析了其成像性能,重点介绍了其在生物医学方面的相关应用,并讨论了编码叠层成像技术未来的发展方向。

关键词：叠层成像编码叠层无透镜成像计算成像显微成像

覆膜对盆栽牡丹根际基质酶活性和微生物多样性的影响

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山东农业科学 2024年第6期56卷 75-80页

作者：赵明君史帅营李世奇史国安河南科技大学牡丹学院/河南省牡丹综合利用工程技术研究中心河南洛阳471023

覆膜能够改变植物根际土壤酶活性和微生物群落结构。本研究采用高通量测序和生物信息学方法,对春、夏两季覆膜和不覆膜盆栽牡丹根际基质的酶活性和微生物多样性变化进行测定与分析。结果表明,覆膜显著提高盆栽牡丹根际基质酶活性,中性... 详细信息

覆膜能够改变植物根际土壤酶活性和微生物群落结构。本研究采用高通量测序和生物信息学方法,对春、夏两季覆膜和不覆膜盆栽牡丹根际基质的酶活性和微生物多样性变化进行测定与分析。结果表明,覆膜显著提高盆栽牡丹根际基质酶活性,中性磷酸酶活性变化最为显著,脲酶次之;改变了微生物群落结构组成和优势菌群相对丰度,芽单胞菌门(Gemmatimonadota)和变形菌门(Proteobacteria)的相对丰度有所提升,梭菌属(Faecalibacterium)和拟杆菌属(Bacteroides)的相对丰度发生变化;提高了根际微生物群落Alpha多样性,Simpson和Shannon指数均有所提高,但夏季覆膜降低菌群丰度;季节对微生物群落Beta多样性影响较大,覆膜有改变细菌距离的趋势。该研究结果可为进一步探讨覆膜对盆栽牡丹微生态环境的影响提供重要参考,为覆膜技术在盆栽牡丹生产中应用提供理论依据。

关键词：覆膜盆栽牡丹根际基质酶活性微生物多样性

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Borophene gas sensor

Nano Research 2022年第3期15卷 2537-2544页

作者： Chuang Hou guoan Tai Yi Liu Xiang Liu The State Key Laboratory of Mechanics and Control of Mechanical Structures and Laboratory of Intelligent Nano Materials and Devices of Ministry of Education College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

High-performance gas sensing devices have been extensively studied in industrial production,clinical medicine and environmental *** the materials used to fabricate gas sensors,two-dimensional(2D)materials are viewed as favorable candidate sensing materials because of their high surface-to-volume ratios,abundant surface activity,defect ***,gas sensors based on the previously reported 2D materials have some disadvantages such as poor air-stability and slow dynamic ***,borophene,as a unique 2D material,has been theoretically predicted to have excellent gas sensing characteristic,especially for nitrogen dioxide(NO_(2)).However,the gas sensing property of borophene has not been still reported ***,we report that a chemiresistive sensor device based on borophene shows high sensitivity,fast response,high selectivity,good flexibility and long-time *** is found that the sensor has a low experimental detection limit of around 200 ppb,a large detection range from 200 ppb to 100 ppm,and fast response time of 30 s and recovery time of 200 s at room temperature,which are remarkably superior to those of reported 2D *** underlying NO_(2) sensing mechanism of borophene is revealed by first-principles *** line with theoretical predication,it has also been confirmed experimentally that the borophene-based sensor has a unique selectivity to NO_(2) compared with other common ***,the sensor also displays superior flexibility and stability under different bending *** study shows excellent electronic and sensing characteristic of borophene,which indicates that it has great potential application value in high-performance sensing and detection in the future.

关键词： borophene gas sensor charge transfer wearable application density functional theory

Probabilistic Model Checking-Based Survivability Analysis in Vehicle-to-Vehicle Networks

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China Communications 2018年第1期15卷 118-127页

作者： Li Jin guoan Zhang Jue Wang School of Electronics and Information Nantong University

Probabilistic model checking has been widely applied to quantitative analysis of stochastic systems, e.g., analyzing the performance, reliability and survivability of computer and communication systems. In this paper, we extend the application of probabilistic model checking to the vehicle to vehicle(V2V) networks. We first develop a continuous-time Markov chain(CTMC) model for the considered V2V network, after that, the PRISM language is adopted to describe the CTMC model, and continuous-time stochastic logic is used to describe the objective survivability properties. In the analysis, two typical failures are considered, namely the node failure and the link failure, respectively induced by external malicious attacks on a target V2V node, and interrupt in a communication link. Considering these failures, their impacts on the network survivability are demonstrated. It is shown that with increasing failure strength, the network survivability is reduced. On the other hand, the network survivability can be improved with increasing repair rate. The proposed probabilistic model checking-based approach can be effectively used in survivability analysis for the V2V networks, moreover, it is anticipated that the approach can be conveniently extended to other networks.

关键词： V2V survivability analysis prob-abilistic model checking PRISM

An emission source inversion model based on satellite data and its application in air quality forecasts

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Science China Earth Sciences 2010年第5期53卷 752-762页

作者： CHENG XingHong XU XiangDe DING guoan Chinese Academy of Meteorological Sciences Beijing 100081China National Climate Center Beijing 100081China

This paper aims at constructing an emission source inversion model using a variational processing method and adaptive nudging scheme for the Community Multiscale Air Quality Model (CMAQ) based on satellite data to investigate the applicability of high resolution OMI (Ozone Monitoring Instrument) column concentration data for air quality forecasts over the North China. The results show a reasonable consistency and good correlation between the spatial distributions of NO2 from surface and OMI satellite measurements in both winter and summer. Such OMI products may be used to implement integrated variational analysis based on observation data on the ground. With linear and variational corrections made, the spatial distribution of OMI NO2 clearly revealed more localized distributing characteristics of NO2 concentration. With such information, emission sources in the southwest and southeast of North China are found to have greater impacts on air quality in Beijing. When the retrieved emission source inventory based on high-resolution OMI NO2 data was used, the coupled Weather Research Forecasting CMAQ model (WRF-CMAQ) performed significantly better in forecasting NO2 concentration level and its tendency as reflected by the more consistencies between the NO2 concentrations from surface observation and model result. In conclusion, satellite data are particularly important for simulating NO2 concentrations on urban and street-block scale. High-resolution OMI NO2 data are applicable for inversing NOx emission source inventory, assessing the regional pollution status and pollution control strategy, and improving the model forecasting results on urban scale.

关键词： OMI NO2 product variational processing method emission source inversion model CMAQ air quality forecast

“以赛促训,以训促学”在第二课堂建设中的探究

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创新创业理论研究与实践 2023年第24期6卷 117-119,126页

作者：原冬伟栾广宇张旭尹国安王秋菊韦春波王建发刘鹏黑龙江八一农垦大学动物科技学院黑龙江大庆163319

“以赛促训,以训促学”是以完善第二课堂教学体系为任务,以课外实践活动为载体,以各级专业技能大赛为目标,培养高素质应用型专门人才。该文以黑龙江八一农垦大学动物科技学院的课堂教学改革为对象,参考国内外先进改革经验和研究成果,提... 详细信息

“以赛促训,以训促学”是以完善第二课堂教学体系为任务,以课外实践活动为载体,以各级专业技能大赛为目标,培养高素质应用型专门人才。该文以黑龙江八一农垦大学动物科技学院的课堂教学改革为对象,参考国内外先进改革经验和研究成果,提出“以赛促训,以训促学”形式,加强和完善课堂教学改革,实现第一课堂和第二课堂的有效衔接,将专业知识和实践技能训练相融合,开展从专业基础技能到专业综合技能的培养,提高学生的综合素质,对高等院校人才培养目标的达成具有重要意义,为培养新农科人才创造了适宜的实践教学模式。

关键词：以赛促训以训促学第二课堂综合素质教学模式教学改革

50 m高砖结构烟囱爆破拆除数值模拟及施工设计

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煤矿爆破 2024年第3期42卷 10-15页

作者：陈欢罗国安杨士昌鲁海生肖健尹俊涛安徽江南爆破工程有限公司安徽宣城242300

针对某复杂环境条件下50 m高砖结构烟囱爆破拆除工况,设计人员采用理论分析方法确定烟囱爆破缺口参数,采用延时爆破开设定向窗、密集空孔代替定位窗的方式控制爆破方向,同时对爆破有害效应进行了估算。为验证爆破方案设计的合理性,设计... 详细信息

针对某复杂环境条件下50 m高砖结构烟囱爆破拆除工况,设计人员采用理论分析方法确定烟囱爆破缺口参数,采用延时爆破开设定向窗、密集空孔代替定位窗的方式控制爆破方向,同时对爆破有害效应进行了估算。为验证爆破方案设计的合理性,设计人员采用数值仿真技术对烟囱倒塌过程进行仿真分析,在砖结构单元之间定义弹簧单元,以还原单元间的黏结滑移效果,仿真结果表明烟囱基本沿设计方向倒塌并出现筒体下坐和中部折断现象。现场爆破过程中,烟囱倒塌过程历时9.0 s,基本与仿真结果一致,触地解离完全,爆破有害效应均得到有效控制,为类似工程提供借鉴。

关键词：砖结构烟囱拆除爆破数值模拟爆破设计

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利用多标签信息的聚类方法

天津理工大学学报 2024年第1期40卷 15-21页

作者：杨国安王志岗天津朗誉科技发展有限公司天津300457 天津理工大学计算机科学与工程学院天津300384

k-means是当前使用最广泛的聚类算法,但其只对无标签信息的样本数据进行聚类,需用户提供初始聚类中心等信息且聚类花费时间长结果不稳定。当前很多数据集都带有多标签的信息,如何利用多标签信息更加快速有效的聚类是一个重要的研究方向... 详细信息

k-means是当前使用最广泛的聚类算法,但其只对无标签信息的样本数据进行聚类,需用户提供初始聚类中心等信息且聚类花费时间长结果不稳定。当前很多数据集都带有多标签的信息,如何利用多标签信息更加快速有效的聚类是一个重要的研究方向。文中提出了多标签数据的聚类方法,首先对多标签信息进行聚类得到适当的初始聚类中心,然后再使用k-means算法对大量样本做聚类。试验结果表明,该聚类方法比使用随机初始聚类中心的k-means算法具有更好的时间性能和聚类结果。

关键词：多标签聚类 k-means 无标签