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A preliminary investigation on the occurrence and distribution of antibiotic resistance genes in the Beijiang River, South China

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Journal of Environmental Sciences 2013年第8期25卷 1656-1661页

作者： Zhenhao Ling Ying Yang Yuanli Huang shichun Zou Tiangang Luan School of Marine Sciences Sun Yat-sen University Department of Civil and Environmental Engineering Hong Kong Polytechnic University Environmental Biotechnology Lab Department of Civil Engineering The University of Hong Kong Guangzhou Quality Supervision and Testing Institute

The occurrence of antibiotic resistance genes （ARGs） was investigated and quantified in 20 water samples collected in the Beijiang River, South China. Sulfonamide- and tetracycline-resistant bacteria were present in 17 and 14 of the collected 20 samples. For sulfonamide ARGs, sulI and sulII were frequently observed in the Beijiang River. The levels of sulI were higher than sulII （p 〈 0.05）, with the mean values of （1.41 ± 1.12） × 10-2 and （1.58 ± 1.71） × 10-3 copies/16S rDNA, respectively. For tetracycline ARGs, tetG had the highest frequency, 100%, followed by tetA （85%）, tetO （85%）, tetC （70%）, tetX （60%）, tetM （40%） and tetQ （20%）, while tetE and tetS were not detected in all the samples from the Beijiang River. On the other hand, tetC had the highest concentration, ranging from 8.30 × 10-2 to 13.20 copies/16S rDNA. The poor correlation between ARGs and antibiotic concentrations revealed that the self-amplification and persistence of ARGs were the reasons that made ARGs exist in the water environment even though the antibiotic selecting pressure was absent. Because so few field measurements have been conducted for investigating the levels of ARGs in rivers in South China, this study provides an important insight on better understanding the occurrence and spread of ARGs in such an ecosystem.

关键词： antibiotic resistant genes Beijiang River South China

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考虑调节费用补偿的海水抽蓄优化定容策略

电工电能新技术 2024年第4期43卷 63-75页

作者：张彬桥段继儒李咸善李世春万刚三峡大学电气与新能源学院湖北宜昌443002 梯级水电站运行与控制湖北省重点实验室(三峡大学) 湖北宜昌443002 中国长江电力股份有限公司检修厂湖北宜昌443002

通过海上风电与海水抽蓄联合运行参与电网的调峰调度,可有效促进海上风电消纳,助力电网调峰,但需要进行海水抽蓄多目标优化定容研究,解决海水抽蓄成本回收问题以及多目标之间的主观偏好与客观冲突对优化决策的影响等关键问题。为此,本... 详细信息

通过海上风电与海水抽蓄联合运行参与电网的调峰调度,可有效促进海上风电消纳,助力电网调峰,但需要进行海水抽蓄多目标优化定容研究,解决海水抽蓄成本回收问题以及多目标之间的主观偏好与客观冲突对优化决策的影响等关键问题。为此,本文提出了考虑调节费用补偿的海水抽蓄多目标优化定容方法,通过海水抽蓄调节费用双向补偿机制,保障抽蓄调节利益;考虑风电不确定性,计及风蓄联合出力跟踪电网负荷误差最小、海上风电运营效益最大和海水抽蓄收益最大,建立风蓄联合运行多目标优化模型,实现多主体利益共赢。以双向补偿电价、海水抽蓄上水库容量、海水抽蓄机组容量为优化决策变量,通过NSGA-Ⅱ方法优化得到Pareto前沿解集;通过K-means算法对Pareto前沿解集进行聚类作为备选方案;采用层次分析法-熵权法进行主、客观赋权;通过TOPSIS方法将备选方案与理想方案比较排序选出最优解。仿真算例结果验证了本文海水抽蓄优化定容方案能够兼顾新能源消纳效果与多主体利益共赢。

关键词：海水抽水蓄能海上风电 NSGA-Ⅱ算法多目标优化

^(18)F-FDG PET/CT联合CT三维重建鉴别肺结节良恶性的回顾性队列研究

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中国胸心血管外科临床杂志 2024年第3期31卷 357-363页

作者：陈勇吴俊陆世春孙超束余声王霄霖大连医科大学辽宁大连116044 苏北人民医院胸外科江苏扬州225009

目的探讨^(18)F-FDG正电子发射计算机体层显像(positron emission tomography/computed tomography,PET/CT)联合CT三维重建(CT three-dimensional reconstruction,CT-3D)对肺结节良恶性鉴别诊断的准确性。方法回顾性分析2020年7月—2021年8月于苏北人民医院胸外科行手术治疗的肺结节患者。提取患者术前^(18)F-FDG PET/CT和胸部增强CT-3D等影像学资料,通过受试者工作特征(receiver operating characteristic,ROC)曲线下面积(area under the curve,AUC)筛选具有诊断意义的参数,通过二元logistic回归分别建立PET/CT预测模型(PET/CT prediction model,MOD PET)、CT-3D预测模型(CT-3D prediction model,MOD CT-3D)和PET/CT联合CT-3D的预测模型(MOD combination),再通过ROC曲线验证模型的诊断效能。结果共纳入125例患者,其中男57例、女68例,平均年龄(61.16±8.57)岁。良性病变46例,恶性肿瘤79例。共提取2个PET/CT参数和5个CT-3D参数,其中PET/CT参数中SUVmax≥1.5(AUC=0.688)和肺门/纵隔淋巴结代谢摄取异常(AUC=0.671)被纳入回归模型,CT-3D参数中CT直方图峰(AUC=0.694)和三维形态(AUC=0.652)被纳入回归模型。最后验证MOD PET的AUC为0.738[95%CI(0.651,0.824)],敏感性为74.7%,特异性为60.9%;MOD CT-3D的AUC为0.762[95%CI(0.677,0.848)],敏感性为51.9%,特异性为87.0%;MOD combination的AUC为0.857[95%CI(0.789,0.925)],敏感性77.2%,特异性82.6%,差异有统计学意义(P<0.001)。结论^(18)F-FDG PET/CT联合CT-3D可提高肺结节的诊断效能,其特异性和敏感性均优于单种影像学诊断方法;联合预测模型对肺结节手术时机和手术方式的选择具有重要意义,为肺结节诊断人工智能化提供理论依据。

关键词：肺结节三维重建正电子发射计算机体层显像 logistic模型人工智能

煤层气采出水阴极结垢的影响分析与减缓技术优化试验

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粘接 2024年第6期51卷 134-137页

作者：田涛唐玉虎张世春陕西新泰能源有限公司陕西彬州713500

为减缓煤层气采出水阴极结垢量,保障设备长期稳定运行,开展了煤层气采出水电絮凝结垢减缓试验,并分析了软化水比例、极板间距、电流密度、处理量等因素对未软化、完全软化和部分软化3种电絮凝处理效果的影响。试验结果表明,当极板间距为... 详细信息

为减缓煤层气采出水阴极结垢量,保障设备长期稳定运行,开展了煤层气采出水电絮凝结垢减缓试验,并分析了软化水比例、极板间距、电流密度、处理量等因素对未软化、完全软化和部分软化3种电絮凝处理效果的影响。试验结果表明,当极板间距为20 mm、电流密度为10 mA/cm^(2)、软化水比例1∶20。处理量为30 L/h时,3种电絮凝处理效果最好,阴极结垢量分别为0.81、0.12、0.13 g,单价分别为0.35、9.82、0.80元/m^(3)。综合考虑处理效果和单价成本,最终确定煤层气采出水的最佳结垢减缓电絮凝方式为部分软化电絮凝。

关键词：煤层气采出水阴极结垢量悬浮物去除率电絮凝

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Atomic phase diagram

Progress in Natural Science:Materials International 2004年第2期14卷 17-22页

作者： LI shichun*(Materials Department, University of Petroleum, Dongying 257061, China) Materials Department University of Petroleum Dongying 257061 China

Based on the Thomas-Fermi-Dirac-Cheng model, atomic phase diagram or electron density versus atomic radius diagram describing the interaction properties of atoms of different kinds in equilibrium state is developed. Atomic phase diagram is established based on the two-atoms model. Besides atomic radius, electron density and continuity condition for electron density on interfaces between atoms, the lever law of atomic phase diagram involving other physical parameters is taken into account, such as the binding energy, for the sake of simplicity.

关键词： TFDC model atom phase diagram two-atoms model electron density atomic radius.

Local PM_(10) and PM_(2.5) emission inventories from agricultural tillage and harvest in northeastern China

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Journal of Environmental Sciences 2017年第7期29卷 15-23页

作者： Weiwei Chen Daniel Q Tong shichun Zhang Xuelei Zhang Hongmei Zhao Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of Sciences Cooperative Institute for Climate & Satellites University of Maryland Center for Spatial Information Science and Systems George Mason University

Mineral particles or particulate matters（PMs） emitted during agricultural activities are major recurring sources of atmospheric aerosol ***,precise PM inventory from agricultural tillage and harvest in agricultural regions is challenged by infrequent local emission factor（EF） *** understand PM emissions from these practices in northeastern China,we measured EFs of PM_（10） and PM_（2.5） from three field operations（i.e.,tilling,planting and harvesting） in major crop production（i.e.,corn and soybean）,using portable real-time PM analyzers and weather station ***-level PM_（10） and PM_（2.5） emissions from agricultural tillage and harvest were estimated,based on local EFs,crop areas and crop *** EFs averaged（107 ± 27）,（17 ± 5） and 26 mg/m^2 for field tilling,planting and harvesting under relatively dry conditions（i.e.,soil moisture 〈15%）,*** EFs of PM from field tillage and planting operations were negatively affected by topsoil *** magnitude of PM_（10） and PM_（2.5） emissions from these three activities were estimated to be 35.1 and 9.8 kilotons/yr in northeastern China,respectively,of which Heilongjiang Province accounted for approximately45%.Spatiotemporal distribution showed that most PM_（10） emission occurred in April,May and October and were concentrated in the central regions of the northeastern plain,which is dominated by dryland *** work is needed to estimate the contribution of agricultural dust emissions to regional air quality in northeastern China.

关键词： PM Emission factor Agricultural inventory Tillage Harvest Burning

SImuLATION OF CYLINDRICAL UPSETTING OF POROUS MATERIALS BY FINITE ELEMENT METHOD

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中国有色金属学会会刊：英文版 1998年第1期8卷 25-28,142页

作者： Zhang, Xingquan Peng, Yinghong Ruan, Xueyu Li, Miaoquan Wu, shichun Shanghai Jiao Tong Univ Shanghai China

ＳＩＭＵＬＡＴＩＯＮＯＦＣＹＬＩＮＤＲＩＣＡＬＵＰＳＥＴＴＩＮＧＯＦＰＯＲＯＵＳＭＡＴＥＲＩＡＬＳＢＹＦＩＮＩＴＥＥＬＥＭＥＮＴＭＥＴＨＯＤ①ＺｈａｎｇＸｉｎｇｑｕａｎ，ＰｅｎｇＹｉｎｇｈｏｎｇａｎｄＲｕａｎＸｕｅｙ... 详细信息

ＳＩＭＵＬＡＴＩＯＮＯＦＣＹＬＩＮＤＲＩＣＡＬＵＰＳＥＴＴＩＮＧＯＦＰＯＲＯＵＳＭＡＴＥＲＩＡＬＳＢＹＦＩＮＩＴＥＥＬＥＭＥＮＴＭＥＴＨＯＤ①ＺｈａｎｇＸｉｎｇｑｕａｎ，ＰｅｎｇＹｉｎｇｈｏｎｇａｎｄＲｕａｎＸｕｅｙｕＮａｔｉｏｎａｌＤｉｅ＆Ｍｏｌｄ...

关键词： porous metal materials the critical technological parameters defects

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中红外波段差分吸收检测气体池设计与实验

大气与环境光学学报 2024年第4期19卷 456-467页

作者：王怡李仕春刘若彤刘家辉辛文辉西安理工大学机械与精密仪器工程学院陕西西安710048 陕西省现代装备绿色制造协同创新中心陕西西安710048

针对中红外波段差分吸收激光雷达探测性能标定的问题,设计并搭建了中红外波段差分吸收检测直通型气体池,以开展大气苯系物差分吸收光谱检测实验。以中红外带间级联激光器为光源,结合带间级联激光器的发射光束参数,设计了直通型气体池的... 详细信息

针对中红外波段差分吸收激光雷达探测性能标定的问题,设计并搭建了中红外波段差分吸收检测直通型气体池,以开展大气苯系物差分吸收光谱检测实验。以中红外带间级联激光器为光源,结合带间级联激光器的发射光束参数,设计了直通型气体池的结构参数和光学参数,测试了3187.0 nm和3235.3 nm波段的气体池透光特性和密封性能,并在此基础上,以苯为例开展了差分吸收激光雷达探测标定实验。结果表明,该气体池在测试波段的透光率大于85%,100 h的负气压减少约13 kPa,差分吸收光谱检测标定实验的相关系数为0.995,完全满足中红外波段差分吸收激光雷达的标定要求。

关键词：光谱检测差分吸收技术直通型气体池中红外波段苯浓度

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Temporal variability of atmospheric particulate matter and chemical composition during a growing season at an agricultural site in northeastern China

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Journal of Environmental Sciences 2015年第12期27卷 133-141页

作者： Weiwei Chen Daniel Tong shichun Zhang Mo Dan Xuelei Zhang Hongmei Zhao Northeast Institute of Geography and Agroecology Chinese Academy of Sciences National Oceanic and Atmospheric Administration (NOAA) Beijing municipal Institute of Labor Protection

This study presents the observations of PM10 and PM2.5 concentrations at an agricultural site from April to October 2012 in Dehui city,*** air was sampled by filter-based samplers and online PM *** filter samples were analyzed to determine the abundance of ionic/inorganic elements,organic carbon（OC） and elemental carbon（EC）.The daily PM10 concentrations varied significantly over the monitoring period,with an average of168 ± 63（in the range of 52-277） μg/m^3 during the land preparation/planting period（26 April-15 June）,85 ± 65（36-228） μg/m^3 during the growing season（16 June-25 September）,and 207 ±88（103-310） μg/m^3 during the harvest period（26 September-31 October）.PM2.5 accounted for44%,56%and 66%of atmospheric PM10 during these periods,*** PM10 diurnal variation showed a distinct peak from 16：00 to 21：00（LST） during the growing and harvesting seasons,while a gradual increase throughout the daytime until 17：00 was observed during tilling *** dust elements（Al,Ca,Fe,and Mg） dominated the PM10 chemical composition during the tilling season;OC,NO3^-,SO4^（2-） and NH4~＋ during the growing season;and carbonaceous species（i.e.,OC and EC） during the harvesting *** results indicate that the soil particles emitted by farm tillage and organic matter released from straw burning are the two most significant sources of PM10 emissions contributing to the recurring high pollution events in this ***,development of agricultural PM inventories from soil tillage and straw burning is prioritized to support air quality modeling.

关键词： PM10 PM2.5 Emission factor Agricultural inventory Tillage Harvest Burning