检索结果-南通市图书馆

中国海洋大学学报:英文版 2023年第5期22卷 1253-1268页

作者： LIU Bo HU Rijun WANG Yonghong LI Yi ZHU Longhai ZHANG xiaodong yuan xiaodong College of Marine Geosciences Ocean University of ChinaQingdao 266100China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationOcean University of ChinaQingdao 26610China Huaneng Xiapu Nuclear Power Co.Ltd. Ningde 352000China

Based on the contents of six heavy metal elements in surface sediments from coastal areas of Fujian Province,the distribution characteristics and controlling factors of six heavy metals in a bay-island-estuary system(BIES)were studied.This paper focuses on the influence of the hydrodynamic environment,and systematically discusses how grain size compositions,chemical environment,tidal current,ocean circulation and human activities influence the distribution and transportation of the heavy metals.The results indicated that the distribution and migration of Cu,Pb,Zn and Cr elements were mainly controlled by natural factors such as regional geological background,grain size compositions,and tidal residual currents.In contrast,As and Hg was mainly affected by human factors such as agriculture and industrial manufacturing.In the BIES,where the chemical environment exerted limited influence,the accumulation and migration of heavy metals are mainly influenced by human activities and enhanced by estuary processes as well as the complex sedimentary dynamic environment caused by many bays and islands.

关键词： heavy metals sediments source to sink controlling factors hydrodynamic environment

Study on the Sediment Transport Flux and Mechanism in the Bohai Strait at the Tidal and Monthly Scales in Summer

在线全文

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2023年第1期22卷 75-87页

作者： yuan xiaodong FENG Xiuli HU Rijun JIANG Shenghui ZHONG Wei College of Marine Geoscience Ocean University of ChinaQingdao 266100China Key Laboratory of Submarine Geosciences and Prospecting Techniques MOEOcean University of ChinaQingdao 266100China

Based on the data of tidal currents and suspended sediment concentrations observed synchronously at 11 stations in the Bohai Strait lasting for 25 hours,the temporal and spatial variations of currents and suspended sediment concentrations in the Bohai Strait in summer were analyzed.The Study preliminarily discussed the transport mechanism,transport trend and transport flux of suspended sediments in summer,using flux-mechanism decomposition method and numerical simulation.The suspended sediment transport was mainly controlled by advection and next influenced by vertical net circulation,while resuspension is relatively weak in Bohai Strait.The single-width fluxes of investigation stations varied from 3.8 to 89.1 gm^(−1) s^(−1),with the maximum value in Miaodao Strait.The suspended sediment transport trends in Laotieshan channel along the vertical section are obviously distinct.The waters mainly flow out of the Bohai Sea in surface layer,while into the Bohai Sea in bottom layer.However,the transport trends of other channels in the centre and south are consistent vertically.The sediments in the Bohai Strait follows the transport pattern of moving outward from the south and inward from the north in summer,i.e.,the sediments are carried out of the Bohai Sea through the Laotieshan channel,while into the Bohai Sea through other channels.And the outflow flux exceeds the inflow flux in August with the net water flux of 1.4×10^(10)m^(3),basically same as the deliveries of the rivers into the Bohai Sea.Moreover,the suspended sediment flux is 0.33 Mt under the action of tidal residual currents in the Yellow Sea in August.

关键词： Bohai Strait suspended sediment transport numerical simulation summer

Effect of electroacupuncture at different acupoints in treating rapid gastric emptying:Zusanli(ST36)plus Zhongwan(CV12)versus Zhongwan(CV12)alone

在线全文

学校读者我要写书评

暂无评论

Journal of Traditional Chinese Medicine 2021年第2期41卷 326-330页

作者： YUE Gonglei yuan xiaodong GE Xiaobin DU Guangzhong Department of Acupuncture-Moxibustion and Tuina Qilu Hospital of Shandong UniversityJinan 250012China Shandong University of Traditional Chinese Medicine Jinan 250355China

OBJECTIVE:To evaluate the effect of electroacupuncture on rapid gastric emptying by comparing the effectiveness of electroacupuncture at both Zusanli(ST36)and Zhongwan(CV12)(He-Mu acupoints)versus electroacupuncture at Zhongwan(CV12)alone.METHODS:Sixty-five patients were randomly divided into two groups;33 patients in the He-Mu acupoints group received electroacupuncture at both Zusanli(ST36)and Zhongwan(CV12),while 32 patients in the single acupoint group received electroacupuncture only at Zhongwan(CV12).Both groups were treated once daily for 30 min,five times per week for 3 weeks.Before and after the 3-week treatment course,patients underwent gastric emptying scintigraphy and were assessed using the Traditional Chinese Medicine(TCM)symptom scale of gastrointestinal diseases.The two groups were compared regarding the percentages of gastric retention at 30 and 60 min and the TCM symptom scores.RESULTS:After the treatment course,the percentages of gastric retention at 30 and 60 min were significantly improved in both groups compared with the pre-treatment values(P<0.01).The improvement in the gastric retention was significantly better in the He-Mu acupoints group than the single acupoint group at 30 min(P<0.01)and 60 min(P<0.05).The TCM symptom score was significantly decreased after the treatment course in both groups(P<0.01).The improvement in the TCM symptom score was significantly better in the He-Mu acupoints group than the single acupoint group(P<0.01).The total effective rate was 93.55%(29/31)in the He-Mu acupoints group and 77.42%(24/31)in the single acupoint group.The treatment effect was better in the He-Mu acupoints group than the single acupoint group(P<0.05).CONCLUSIONS:Electroacupuncture at both Zusanli(ST36)and Zhongwan(CV12)or at Zhongwan(CV12)alone is effective in treating rapid gastric emptying.Furthermore,electroacupuncture at both Zusanli(ST36)and Zhongwan(CV12)is more effective than electroacupuncture at Zhongwan(CV12)alone.

关键词： gastric emptying electroacupuncture point ST 36(Zusanli) point CV 12(Zhongwan) Points He-Mu

短路电流对二次设备电磁干扰分析及抗干扰措施

在线全文

学校读者我要写书评

暂无评论

高压电器 2024年第1期60卷 182-189页

作者：张赢袁晓东曹春诚程显朱剑鹏国网呼伦贝尔供电公司内蒙古呼伦贝尔021100 郑州大学电气工程学院郑州450000 河南省输配电装备与电气绝缘工程技术研究中心郑州450000

目前智能配电网的建设不断推进,加快了配电开关一二次设备相关技术的发展,也对长期处于复杂电磁环境下的二次设备提出了更高的要求。文中基于合成试验回路搭建了短路电流对配电开关二次设备电磁干扰试验平台,开展开断故障电流对相关干... 详细信息

目前智能配电网的建设不断推进,加快了配电开关一二次设备相关技术的发展,也对长期处于复杂电磁环境下的二次设备提出了更高的要求。文中基于合成试验回路搭建了短路电流对配电开关二次设备电磁干扰试验平台,开展开断故障电流对相关干扰对成套设备的影响研究,分析干扰信号产生原因、频谱特性。针对干扰的特性设计一套抗干扰测量系统,利用ATP-EMTP模拟合成回路进行仿真分析并进行实际测试验证。结果表明:成套设备进行开断试验时,二次设备端口会受到较大的干扰。电流波形也会发生畸变,干扰电流的最高可到26 A,且干扰电流受电流互感器磁饱和和退饱和的影响,通过增加抗干扰措施,二次设备输出准确度与之相比提升约40%。本次的试验结果可为一二次融合成套设备中二次设备电磁兼容研究提供相关依据。

关键词：一二次融合电磁干扰合成试验回路暂态恢复电压 ATP-EMTP 二次设备

Multi-source genesis of continental carbonate-rich fine-grained sedimentary rocks and hydrocarbon sweet spots

在线全文

学校读者我要写书评

暂无评论

Petroleum Exploration and Development 2021年第1期48卷 30-42页

作者： JIANG Zaixing KONG Xiangxin YANG Yepeng ZHANG Jianguo ZHANG yuanfu WANG Li yuan xiaodong School of Energy Resources China University of Geosciences(Beijing)Beijing 100083China

This paper systematically discusses the multiple source characteristics and formation mechanisms of carbonate-rich fine-grained sedimentary rocks through the analysis of material source and rock formation.The hydrocarbon accumulation characteristics of carbonate-rich fine-grained sedimentary rocks are also summarized.The results show that the main reason for the enrichment of fine-grained carbonate materials in rift lake basins was the supply of multiple material sources,including terrestrial material input,formation of intrabasinal authigenic carbonate,volcanic-hydrothermal material feeding and mixed source.The development of carbonate bedrock in the provenance area controlled the filling scale of carbonate materials in rift lake basins.The volcanic-hydrothermal activity might provide an alkaline fluid to the lake basins to strengthen the material supply for the formation of carbonate crystals.Authigenic carbonate crystals induced by biological processes were the main source of long-term accumulation of fine-grained carbonate materials in the lake basins.Carbonate-rich fine-grained sedimentary rocks with multiple features were formed through the interaction of physical,biochemical and chemical processes during the deposition and post-deposition stages.The source and sedimentary origin of the fine-grained carbonate rock controlled the hydrocarbon accumulation in it.In the multi-source system,the types of"sweet spots"of continental shale oil and gas include endogenous type,terrigenous type,volcanic-hydrothermal type and mixed source type.

关键词： carbonate-rich fine-grained sedimentary rocks rift lake basins multiple sources hydrocarbon accumulation sweet spot of continental shale oil and gas

基于多期相CT图像的深度学习ResNet18和ResNet50模型诊断肾结核的效能比较

在线全文

学校读者我要写书评

暂无评论

中国防痨杂志 2024年第3期46卷 288-293页

作者：易婉晴郑雪怡张状孙维荣袁小东河北北方学院张家口075000 秦皇岛市第二医院医学影像科秦皇岛066000 解放军总医院第八医学中心放射诊断科北京100089

目的:探讨基于CT图像构建深度学习模型对肾结核进行鉴别诊断的可行性。方法:回顾性分析2018年9月至2020年8月经解放军总医院第八医学中心收治,并经组织病理学或临床确诊的肾结核、肾肿瘤、肾盂肾炎、正常肾脏、肾囊肿、肾积水患者。共纳... 详细信息

目的:探讨基于CT图像构建深度学习模型对肾结核进行鉴别诊断的可行性。方法:回顾性分析2018年9月至2020年8月经解放军总医院第八医学中心收治,并经组织病理学或临床确诊的肾结核、肾肿瘤、肾盂肾炎、正常肾脏、肾囊肿、肾积水患者。共纳入200例患者共400个肾脏的CT图像数据。将400个肾脏CT图像分为结核组(114个)和非结核组(286个),并且按8∶2的比例分为训练集(肾结核:85个;非肾结核:235个)和测试集(肾结核:29个;非肾结核:51个)。基于训练集通过ResNet18和ResNet50网络分别构建肾脏平扫期、皮髓质期、实质期和排泄期的深度学习模型;基于测试集评估所构建模型对肾结核的诊断效能,计算受试者工作特征曲线(ROC)曲线下面积(AUC)、敏感度、特异度、准确率和F1分数。结果:训练集中,结核组平均年龄为(41.27±11.75)岁,明显低于非结核组[(54.05±13.97)岁];测试集中,结核组平均年龄为(44.06±11.95)岁,明显低于非结核组[(56.12±10.73)岁],差异均有统计学意义(t值分别为5.753、3.444,P值均<0.05)。训练集中,结核组男性占66.7%(40/60),女性占33.3%(20/60);非结核组男性占60.9%(78/128),女性占39.1%(50/128);两组差异无统计学意义(χ^(2)=0.009,P=0.924)。测试集中,结核组男性占64.3%(18/28),女性占35.7%(10/28);非结核组男性占58.7%(27/46),女性占41.3%(19/46);两组差异无统计学意义(χ^(2)=0.018,P=0.894)。ResNet18模型肾脏各期相的AUC、敏感度、特异度、准确率和F1分数均高于ResNet50模型。ResNet18模型中以皮髓质期为最佳,AUC、敏感度、特异度、准确率和F1分数分别为0.925、93.1%、86.3%、88.7%和0.857;ResNet50模型皮髓质期AUC、敏感度、特异度、准确率和F1分数分别为0.858、72.4%、84.3%、80.0%和0.724。结论:基于多期相CT图像的ResNet18模型诊断肾结核的效能优于ResNet50模型,ResNet18模型中以皮髓质期诊断效能最佳,有较高的临床应用价值。

关键词：结核,肾体层摄影术 X线计算机图像解释,计算机辅助诊断,鉴别

Rapid Amplification of 5′ cDNA End of S. Liaotungensis Choline Monooxygenase Using Inverse PCR RACE

在线全文

学校读者我要写书评

暂无评论

High Technology Letters 2002年第1期8卷 5-7页

作者：李秋莉 Gao Xiaorong FAN Qi yuan xiaodong Liu Dawei An Lijia Bioengineering Department of Dalian University of Technology Dalian 116012 P.R.China Biology Department of Liaoning Normal University Dalian 116029 P.R.China Bioengineering Department of Dalian University of Technology Dalian 116012 P.R.China TaKaRa Biotechnology Dalian Co. Ltd. Dalian 116600 P.R.China

Based on part of a known cDNA sequence of Suaeda Liaotungensis choline monooxygenase, the authors successfully cloned the 5′ cDNA end of Suaeda Lianotungensis choline monooxygenase using Inverse PCR RACE with a specially designed 5′-phosphated RT primer and two pairs of specific inverse PCR primers. Compared with the anchored PCR RACE, inverse PCR RACE has better specificity and higher amplification.

关键词： DNA 放大反演PCR RACE应用

在线全文

学校读者我要写书评

暂无评论

基于混合电解槽制氢系统的功率分配技术

电力系统自动化 2024年第13期48卷 9-18页

作者：李建林赵文鼎梁忠豪缪惠宇袁晓冬国家能源用户侧储能创新研发中心(北方工业大学) 北京市100144 国网江苏省电力有限公司电力科学研究院江苏省南京市211103

光伏(PV)电解水制氢技术是实现PV消纳和绿电制氢的重要手段。在波动电源输入状态下,电解槽制氢系统运行稳定性及制氢经济性存在较多问题。针对这些问题,提出基于混合电解槽制氢系统的PV制氢方案,采用碱性电解槽(AEL)制氢系统与质子交换... 详细信息

光伏(PV)电解水制氢技术是实现PV消纳和绿电制氢的重要手段。在波动电源输入状态下,电解槽制氢系统运行稳定性及制氢经济性存在较多问题。针对这些问题,提出基于混合电解槽制氢系统的PV制氢方案,采用碱性电解槽(AEL)制氢系统与质子交换膜电解槽(PEMEL)系统相结合的方法,提出混合电解槽制氢系统功率优化控制技术和容量配置方法,在实现不同类型电解槽组合运行、合理配置的基础上,提升制氢性能。结果表明,混合电解制氢系统与单一AEL制氢技术相比,制氢量提升了5%,波动率大幅降低,制氢成本相较于PEMEL电解水制氢系统大幅降低。采用功率优化控制技术后,同等功率运行下,制氢量提升。单一电解槽处于波动工况下,采用阵列轮换方式保证了电解槽系统安全运行。研究结果可以为实现PV消纳以及多类型电解槽安全运行模式提供参考。

关键词：光伏发电碱性电解槽质子交换膜电解槽容量配置功率分配

在线全文

学校读者我要写书评

暂无评论

车联网环境下电动汽车主动充电引导模型

电力系统自动化 2024年第7期48卷 159-168页

作者：袁晓冬甘海庆王明深滕欣元阮文骏龙寰国网江苏省电力有限公司电力科学研究院江苏省南京市211103 国网江苏省电力有限公司江苏省南京市210024 东南大学电气工程学院江苏省南京市210096

为了适应电动汽车数量和充电需求的急剧增长,从电动汽车用户视角出发,提出了一种在车联网环境下基于改进A*路径规划算法与排队论的电动汽车主动充电引导模型。首先,融入红绿灯等待时间和不走回头路条件,改进A*路径规划算法,利用实际路... 详细信息

为了适应电动汽车数量和充电需求的急剧增长,从电动汽车用户视角出发,提出了一种在车联网环境下基于改进A*路径规划算法与排队论的电动汽车主动充电引导模型。首先,融入红绿灯等待时间和不走回头路条件,改进A*路径规划算法,利用实际路网状态信息更新路网时空状态矩阵,实时优化电动汽车行驶路径,获取电动汽车充电行驶时间。其次,利用深度置信网络预测充电站电动汽车短时到达量,基于排队论M/G/k模型预测电动汽车充电等待时间。最后,以最小化电动汽车充电行驶时间和充电等待时间为目标,搭建电动汽车主动充电引导模型。以中国南京市中心区域为算例,验证了所提主动充电引导模型的有效性,所提算法能够提高充电桩的利用率并减少电动汽车用户综合充电时间。

关键词：车联网电动汽车主动充电引导排队论路径规划

基于参数自调节的电氢耦合系统调频控制策略研究

在线全文

学校读者我要写书评

暂无评论

高压电器 2024年第7期60卷 1-11页

作者：李建林胡笳扬辛迪熙曾飞袁晓冬北方工业大学国家能源用户侧储能创新研发中心北京100144 国网江苏省电力有限公司电力科学研究院南京211103

针对含质子交换膜燃料电池(proton exchange membrane fuel cell,PEMFC)的氢储能系统频率控制问题,为提高氢储能系统的频率稳定性,提出了一种基于虚拟参数自调节的系统频率控制策略。其中,电氢耦合系统以PEMFC为依托,光伏、储能电池为辅... 详细信息

针对含质子交换膜燃料电池(proton exchange membrane fuel cell,PEMFC)的氢储能系统频率控制问题,为提高氢储能系统的频率稳定性,提出了一种基于虚拟参数自调节的系统频率控制策略。其中,电氢耦合系统以PEMFC为依托,光伏、储能电池为辅助,通过PEMFC、光伏、储能电池三者混合向系统综合负荷供电。通过数学模型构建,观察出系统内发生微小扰动后,PEMFC及储能电池的动态响应变化,改变虚拟控制参数,调整系统内的功率分配。由于PEMFC和储能电池动态响应时间不同,对于PEMFC和储能电池采取不同的控制策略,具体体现为对PEMFC采取下垂控制,而对储能电池采取惯量控制,来达到维持系统内频率在正常范围内微小波动并趋于稳定的目的。最后,通过MATLAB/Simulink仿真平台搭建模型验证了所提策略的有效性和优越性。

关键词：质子交换膜燃料电池电氢耦合下垂控制惯量控制调频参数自调节储能电池光伏