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Characterization and distribution of polycyclic aromatic hydrocarbon in sediments of haihe River, Tianjin, China

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Journal of Environmental Sciences 2007年第3期19卷 306-311页

作者： JIANG Bin zheng hai-long HUANG Guo-qiang DING Hui LI Xin-gang SUO Hong-tu LI Rui School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China Jinzhou Petrochemical Co. Designing Institute Jinzhou 121001 China

In this study sediment samples were collected from 13 sites of haihe River in Tianjin City, China, sixteen of priority polycyclic aromatic hydrocarbons （PAHs） listed in USEPA were analyzed by means of GC-MS. The total concentrations of PAH ranged from 774.81 to 255371.91 ng/g dw, and two to four rings of PAHs were dominant in sediment samples. Molecular ratios, such as phenanthrene/anthracene, fluoranthene/pyrene and low-molecular-weight PAH/high-molecular-weight PAH, were used to study the possible sources of pollution. It indicated a mixed pattern of parolytic and petrogenic inputs of PAHs in sediments in haihe River. The petrogenic PAHs may be mainly derived from the leakage of refined products, e.g., gasoline, diesel fuel and fuel oil vehicle traffics or gas stations from urban area. The pyrolytic PAHs might be from the discharge of industrial wastewater and the emission of atmospheric particles from petrochemical factories. In addition, the levels of PAHs in the urban and industrial areas are far beyond the values reported from other rivers and marine systems reported. This situation may be due to polluted discharging from some petrochemical industrial manufactories and worse traffic conditions in Tianjin.

关键词： PAHs haihe River sediments Tianjin

Localized Structures on Periodic Background Wave of （2＋1）-Dimensional Boiti-Leon-Pempinelli System via an Object Reduction

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Communications in Theoretical Physics 2007年第5X期48卷 811-814页

作者： FANG Jian-Ping MA Song-Hua FEI Jin-Xi HONG Bi-hai zheng Chun-long College of Mathematics and Physics Lishui University Lishui 323000 China

In this paper, we present an object reduction for nonlinear partial differential equations. As a concrete example of its applications in physical problems, this method is applied to the （2＋1）-dimensional Boiti-Leon-Pempinelli system, which has the extensive physics background, and an abundance of exact solutions is derived from some reduction equations. Based on the derived solutions, the localized structures under the periodic wave background are obtained.

关键词： object reduction (2+1)-dimensional Boiti-Leon-Pempinelli system exact solution

Properties of a family of merit functions and a merit function method for the NCP

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Applied Mathematics(A Journal of Chinese Universities) 2010年第4期25卷 379-390页

作者： LU Li-yong HUANG zheng-hai HU Sheng-long Department of Mathematics, School of Science, Tianjin University, Tianjin 300072, China Department of Mathematics School of Science Tianjin University Tianjin China

A family of merit functions are proposed, which are the generalization of several existing merit functions. A number of favorable properties of the proposed merit functions are established. By using these properties, a merit function method for solving nonlinear complementarity problem is investigated, and the global convergence of the proposed algorithm is proved under some standard assumptions. Some preliminary numerical results are given.

关键词： Nonlinear complementarity problem NCP-function merit function merit function method.

A rare case of Castleman disease presenting as pulmonary mass mimicking central pulmonary malignancy

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Chinese Medical Journal 2009年第8期122卷 990-991页

作者： WANG Shao-hua RUAN zheng HUANG hai-long SONG Kang-sheng Department of Thoracic Surgery First People's Hospital Shanghai Jiao Tong University Shanghai 200080 China

Castleman disease is a rare disorder of the lymphoid system characterized by noncancerous growths that may develop in lymph node tissues throughout the body. Most often this occurs in the neck, mediastinum, and abdomen where lymph nodes aggregate. Here we describe a case of asymptomatic intrapulmonary Castleman disease adjacent to the left pulmonary hilum that mimicked central pulmonary malignancy in a 27-year-old man who underwent curative surgical removal of the mass.

关键词： Castleman disease pulmonary malignancy lymph node hyperplasia

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结合慕课理念开展精品视频公开课建设的对策

黑龙江高教研究 2015年第10期33卷 163-165页

作者：郑海龙哈尔滨工程大学国防教育学院黑龙江哈尔滨150001

自2012年的慕课热冲击以来,视频公开课的建设和发展遇到前所未有的困境,慕课将取代视频公开课的呼声越来越高。慕课虽然在网络课程方面有其独到的优势,但是绝不能因为这样,我们就要放弃精品视频公开课的建设,相反,慕课的先进理念恰恰为... 详细信息

自2012年的慕课热冲击以来,视频公开课的建设和发展遇到前所未有的困境,慕课将取代视频公开课的呼声越来越高。慕课虽然在网络课程方面有其独到的优势,但是绝不能因为这样,我们就要放弃精品视频公开课的建设,相反,慕课的先进理念恰恰为精品视频公开课的建设带来了生机,应瞄准当前视频公开课建设中课程内容缺乏合理搭配、教学互动缺乏巧妙设计、教学效果缺乏反馈机制等问题,结合慕课开放性、灵活性和完整性的特点,为视频公开课重新设计建设对策。

关键词：慕课精品视频公开课对策

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铺地锦竹草的试验栽植及城市园林应用

草业科学 2009年第6期26卷 172-176页

作者：郑龙海马龙邓勇章毅杭州浙大园林建设有限公司浙江杭州310027 浙江省绍兴县园林管理处浙江绍兴312030

采用不同光照、不同土壤条件试验，观测铺地锦竹草Callisia repenstg生长特性，得出：日气温18～22℃．夜间温度≥12℃，为植株适宜生长温度；在落叶阔叶林下，铺地锦竹草夏季中午光照强度在10000lx以下，早上及傍晚30000lx以上（斜向... 详细信息

采用不同光照、不同土壤条件试验，观测铺地锦竹草Callisia repenstg生长特性，得出：日气温18～22℃．夜间温度≥12℃，为植株适宜生长温度；在落叶阔叶林下，铺地锦竹草夏季中午光照强度在10000lx以下，早上及傍晚30000lx以上（斜向光）植株生长健状，生长优异；铺地锦竹草对土壤的适应性广泛，对肥力要求不高．只要确保土壤水分充足，无论粉沙土、粘质土、砾质土和石砾。铺地锦竹草都能生长。阐述了铺地锦竹草在城市园林应用中的栽植方法、养护管理措施，对常绿树林下、城市高架桥下及屋顶绿化营植草地和丰富林下景观、改善室内环境具有一定意义。

关键词：铺地锦竹草影响因子养护管理耐荫性地被植物城市园林应用

FS-T_(2)WI联合DWI在乳腺良恶性囊实性病变鉴别诊断中的价值

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中国临床医学影像杂志 2024年第1期35卷 31-34页

作者：郑海龙严高武遂宁市中心医院放射影像科四川遂宁629000

目的:探究T_(2)WI抑脂序列(Fat saturation T_(2)-weighted imaging,FS-T_(2)WI)联合扩散加权成像(Diffusion weighted imaging,DWI)在乳腺良恶性囊实性病变鉴别诊断中的价值。方法:回顾性选取2021年1月—2022年12月于我院治疗的乳腺囊实性病变患者95例,病灶数量113个。于治疗前对患者行FS-T_(2)WI和DWI序列扫描,对影像学图像进行分析,获取ADC值和FS-T_(2)WI不均匀,以手术病理检查结果为金标准,采用受试者工作曲线(ROC)分析FS-T_(2)WI和DWI序列扫描对乳腺良恶性囊实性病变的鉴别效能。结果:对95例患者行病理组织活检,有38例患者存在恶性结节,57例患者无恶性结节,根据此结果将患者分为良性组和恶性组,比较两组患者资料发现,恶性组患者的结节数量明显多于良性组,最大肿瘤直径大于良性组(P<0.05)。病理检查结果显示共有113个结节,其中恶性结节48个,良性结节65个。根据结节性质不同将结节分为良性结节和恶性结节,比较不同结节的FS-T_(2)WI和DWI序列扫描结果发现,良恶性结节囊壁特点、厚度和肿瘤内部强化特征之间差异有统计学意义,且恶性结节平均直径大于良性结节,ADC值和SIR值小于良性结节(P<0.05)。ADC值和SIR值对乳腺囊实性良恶性病变的诊断AUC分别为0.801、0.818,两者联合检测的AUC为0.908,其联合诊断灵敏度和特异度分别为81.3%、86.3%,高于单独诊断的诊断效能。结论:FS-T_(2)WI和DWI序列扫描对于乳腺囊实性良恶性病变均有较高的鉴别诊断价值,且两者联合诊断的灵敏度和特异度均高于单独诊断。

关键词：乳腺肿瘤乳腺疾病磁共振成像

Anatomic structural study of cerebellopontine angle via endoscope

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Chinese Medical Journal 2007年第20期120卷 1836-1839页

作者： XIA Yin LI Xi-ping HAN De-min zheng Jun long hai-shan SHI Jin-feng Department of Otolaryngology,Beijing Tongren Hospital,Capital Medical University Key Laboratory of Otolaryngology Head and Neck Surgery (Capital Medical University),Ministry of Education,Beijing 100730,China (Xia Y,Li XP,Han DM,zheng J,long HS and Shi JF) Department of Otolaryngology Beijing Tongren Hospital Capital Medical UniversityKey Laboratory of Otolaryngology Head and Neck Surgery (Capital Medical University) Ministry of EducationBeijing 100730 China）

Background Minimally invasive surgery in skull base relying on searching for possible anatomic basis for endoscopic technology is controversial. The objective of this study was to observe the spatial relationships between main blood vessels and nerves in the cerebellopontine angle area and provide anatomic basis for lateral and posterior skull base minimally invasive surgery via endoscopic retrosigmoid keyhole approach.Methods This study was conducted on thirty dried adult skulls to measure the spatial relationships among the surface bony marks of posterior cranial fossa, and to locate the most appropriate drilling area for retrosigmoid keyhole approach. In addition, we used 10 formaldehyde-fixed adult cadaver specimens for simulating endoscopic retrosigmoid approach to determine the visible scope.Results The midpoint between the mastoid tip and the asterion was the best drilling point for retrosigmoid approach. A hole centered on this point with the 2.0 cm in diameter was suitable for exposing the related structures in the cerebellopontine angle. Retrosigmoid keyhole approach can decrease the pressure on the cerebellum and expose the related structures effectively which include facial nerve, vestibulocochlear nerve, trigeminal nerve, glossopharyngeal nerve, vagus nerve, accessory nerve, hypoglossal nerve, anterior inferior cerebellar artery, posterior inferior cerebellar artery and labyrinthine artery, etc.Conclusions Exact location on endoscope retrosigmoid approach can avoid dragging cerebellum during the minimally invasive surgery. The application of retrosigmoid keyhole approach will extend the application of endoscopic technology.

关键词： applied anatomy cerebellopontine angle endoscope operative approach

AP1000核电厂安全壳内电缆鉴定试验研究

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电工电气 2016年第4期 49-52页

作者：郑海龙山东核电有限公司山东烟台265116

安全壳内电缆对核电厂安全运行和安全停堆起着重要作用。介绍了AP1000核电厂安全壳内电缆鉴定的主要项目和方法,探讨了热老化试验、辐照老化试验、DBA试验、长期浸没试验等关键试验,分析了试验过程中面临的问题并给出了解决办法,为核电... 详细信息

安全壳内电缆对核电厂安全运行和安全停堆起着重要作用。介绍了AP1000核电厂安全壳内电缆鉴定的主要项目和方法,探讨了热老化试验、辐照老化试验、DBA试验、长期浸没试验等关键试验,分析了试验过程中面临的问题并给出了解决办法,为核电厂电缆鉴定试验以及完善国内相关规范标准提供参考。

关键词：壳内电缆热老化试验辐照老化试验 DBA试验浸没试验特殊试验