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组合型缺陷管道凹陷形成过程的应力应变响应研究

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中国安全生产科学技术 2024年第7期20卷 72-77页

作者：窦广超张颖赵鹏程潘传禹王佳音常州大学安全科学与工程学院江苏常州213164 江苏国信股份有限公司江苏南京210018 青岛青港通达能源有限公司山东青岛266555

为研究组合型缺陷管道的凹陷形成过程,设计完成全尺寸管道外载试验,结合有限元模拟仿真,对组合型缺陷的凹陷形成过程的应力应变响应规律进行深入分析。研究结果表明:靠近缺陷中心处的测点应变变化速率快且幅度大;等效塑性应变最大值位... 详细信息

为研究组合型缺陷管道的凹陷形成过程,设计完成全尺寸管道外载试验,结合有限元模拟仿真,对组合型缺陷的凹陷形成过程的应力应变响应规律进行深入分析。研究结果表明:靠近缺陷中心处的测点应变变化速率快且幅度大;等效塑性应变最大值位于缺陷区域的轴向边缘处;不同凹陷深度下,管道残余应力状态不同,管壁弯曲发生变化;随着凹陷深度的增加,最大等效应力的位置逐渐偏离缺陷中心区域。研究结果可为组合缺陷管道安全评价提供参考。

关键词：组合型缺陷管道应力应变有限元模型全尺寸试验

The chemical distribution characteristics of variant form phosphorus in the seawater of the South China Sea

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Acta Oceanologica Sinica 2003年第3期22卷 385-394页

作者： Jianming pan, chuanyu Hu, Jianfang Chen, Xiaoya Liu, Huaiyang Zhou, Weidong Ji Key Laboratory of Submarine Geosciences of State Oceanic Administration, Second Institute of Oceanography, State O-ceanic Administration, Hangzhou 310012,China. E-mail:panjianming@sio. zj.edu. cnThird Institute of Oceanography, State Oceanic Administration, Xiamen 361005,China Key Lab.Submar.Geosci.St.Ocean.Admin Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China Third Institute of Oceanography State Oceanic Administration Xiamen 361005 China

According to two cruises investigation information in summer and winter during 1998 and 1999, the phosphorous concentration distribution and changes of summer and winter were discussed primarily in the South China Sea. The results show that the phosphate concentration of surface seawater in summer is distinctly lower than that in winter, averaging 0.04 mumol/dm(3) in summer and 0.35 mumol/ dm(3) in winter. The organic phosphorous concentration of surface seawater in summer is higher than that in winter, averaging 0.12 mumol/dm(3) in summer and 0. 04 mumol/dm(3) in winter respectively. The seasonal changes of total phosphorus are similar to phosphate, averaging 0.22 mumol/dm(3) in summer and 0.61 mumol/dm(3) in winter respectively. In vertical direction, phosphate, TDP and TP content are the lowest in upper 50 m water column, and increase in linearity rapidly with water depth, increasing slowly under 500 m, reach to maximum about 1000 m, then decrease slightly with water depth increasing. The vertical distribution is typical in summer, and there is small dispersed for phosphorus concentration for the same depth of different stations. However, in winter there is a large disperse for phosphate, TDP and TP, specifically for phosphate at 200 m at which the concentration is maximum. This result indicates that there are large differences in hydrology and biology conditions that affect largely the chemical environment of the South China Sea. The organic phosphorus is the predominant in surface seawater of the South China Sea, but the inorganic phosphorus is the predominant in layers below depth of 150 m. The organic phosphorus concentration in deep water usually decreases with water depth increasing. The organic phosphorus in summer is remarkably more than that in winter because of the strong biology activities in summer.

关键词： the South China Sea specific form phosphorus biogeochemistry processes

细水雾抑制障碍物遮挡气体池火的缩尺度实验研究

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燃烧科学与技术 2022年第5期28卷 489-497页

作者：刘洋鹏王喜世沈佳杏李国春倪小敏潘传鱼中国科学技术大学火灾科学国家重点实验室合肥230026 浙江大学能源清洁利用国家重点实验室杭州310027 浙江大学湖州研究院湖州313000

大型仓库等场所由于存在明显的障碍物空间遮挡情形,一旦发生火灾,障碍物势必会对细水雾灭火效果及其作用机制产生影响.通过搭建1/6缩尺度实验平台,利用平面激光诱导荧光(PLIF)及粒子图像测速(PIV)技术,获取了细水雾与障碍物遮挡火焰相... 详细信息

大型仓库等场所由于存在明显的障碍物空间遮挡情形,一旦发生火灾,障碍物势必会对细水雾灭火效果及其作用机制产生影响.通过搭建1/6缩尺度实验平台,利用平面激光诱导荧光(PLIF)及粒子图像测速(PIV)技术,获取了细水雾与障碍物遮挡火焰相互作用的火焰羟基自由基浓度分布及细水雾流场数据.结果表明,细水雾可以有效熄灭最大有效雾量比大于0.59且火焰功率小于3.93 kW的遮挡火焰.PIV拍摄视场下雾滴最大速度随细水雾施加时间的特征规律,揭示了灭火过程中雾-焰相互竞争的动力学机制.

关键词：细水雾障碍物遮挡火缩尺度实验火焰抑制

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矿山法隧道超前帷幕注浆施工技术研究

智能建筑与工程机械 2019年第4期1卷 45-47页

作者：宗朝阳潘传宇周旋中建铁路投资建设集团有限公司北京100032

本文通过对徐州轨道交通3号线南翟区间隧道矿山法隧道全断面超前帷幕注浆施工经验分析,从施工准备、止浆墙施做、钻孔、注浆、效果检查等方面总结阐述了超前帷幕注浆的施工工艺和控制要点,为类似工程提供借鉴和参考。

关键词：止浆墙钻孔注浆帷幕浆液

混合式学习中心:基于教育数字化的图书馆阅读服务研究

维普期刊数据库评论

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图书馆界 2024年第2期 18-22,59页

作者：赵文萱冯川玉潘健金陵图书馆江苏南京210019

在教育数字化背景下,图书馆作为人类文化传递中心和知识交流中心,理应主动适应时代的发展要求,充分发挥其服务作用及价值,共谋未来学习发展新方向。通过阐述混合式学习的内涵特征及其在图书馆阅读服务中的应用价值,归纳总结图书馆学习... 详细信息

在教育数字化背景下,图书馆作为人类文化传递中心和知识交流中心,理应主动适应时代的发展要求,充分发挥其服务作用及价值,共谋未来学习发展新方向。通过阐述混合式学习的内涵特征及其在图书馆阅读服务中的应用价值,归纳总结图书馆学习中心研究实践现状,从构成要素、流程设计、组织模式3个方面明确混合式学习在图书馆阅读服务中的实践路径,探索图书馆混合式学习的空间、资源、通道及人与机器的具体服务重点和策略,推动图书馆事业创新与转型发展。

关键词：教育数字化混合式学习中心图书馆阅读服务

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Characteristics of particle fluxes in the Prydz Bay polynya, Eastern Antarctica

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Science China Earth Sciences 2019年第4期62卷 657-670页

作者： Zhengbing HAN chuanyu HU Weiping SUN Jun ZHAO Jianming pan Gaojing FAN Haisheng ZHANG Second Institute of Oceanography Ministry of Natural Resources Key Laboratory of Marine Ecosystem and Biogeochemistry State Oceanic Administration China University of Geosciences

The settling of particulate carbon in seawater is a key component of the ocean carbon cycle. We deployed a set of sediment trap in the polynya of Prydz Bay from December 2010 to December 2011 to investigate the seasonal variations in particle fluxes. There was a clear seasonal variation in the particle fluxes, with maximum and minimum fluxes recorded during the summer and winter, respectively. The average total flux over the sampling period was 193.58 mg m^(-2)d^(-1), and the average fluxes of organic carbon(C_(org)), inorganic carbon(C_(inorg)), and biogenic silica(Si_(bio)) were 721.78, 28.67, and 2382.80 μmol m^(-2) d^(-1), respectively. Si_(bio)was the main contributor to the total mass flux, and strongly correlated with C_(org). The high Si_(bio)/C_(org)molar ratios(>1) suggest that C_(org)was transported to deep sea in association with Si_(bio). By comparing remote sensing data of sea ice and chlorophyll in the upper water column, we found that the dynamics of carbon fluxes were closely related to changes in sea ice. Algae in sea ice may have a key role in biological pump processes in early summer. Apart from the ice algae bloom period, variations in carbon fluxes generally corresponded with phytoplankton blooms in the upper water. The ballast effect controlled the particle settling velocity and the efficiency of the biological pump. Sea ice rafts initiated the first particle export event and enhanced the particle settling efficiency during melting period. As diatoms might become less dominant in the ice-free area, sea ice loss may cause the efficiency of the biological pump efficiency to decrease over the long term.

关键词： Prydz Bay Particle fluxes Polynya Ballast effect Biological pump efficiency

Changes in soil free-living diazotrophic community and co-occurrence patterns along desert wetland degradation gradient in the Mu Us Desert,northern China

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Pedosphere 2023年第4期33卷 638-648页

作者： Kun WANG Hongyan FEI Qian TONG chuanyu WAN Ruopeng pan Fengpeng HAN State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau College of Natural Resources and EnvironmentNorthwest A&F UniversityShaanxi 712100(China) Research Center on Soil&Water Conservation Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesShaanxi 712100(China)

Climate change and human activity have led to the degradation of desert ***-living diazotrophs are vital for soil nitrogen ***,a comprehensive understanding of how soil free-living diazotrophic communities and their co-occurrence patterns respond to desert wetland degradation is ***,quantitative polymerase chain reaction(qPCR),amplicon sequencing targeting nitrogenase gene(nifH),and network analysis were used to investigate the abundance,diversity,community composition,and co-occurrence patterns of soil free-living diazotrophs along the wetland degradation gradient,i.e.,non-degraded(ND),lightly degraded(LD),moderately degraded(MD),and severely degraded(SD),in the southeastern Mu Us Desert,northern *** abundance and Shannon,Simpson,Chao 1,and ACE indexes decreased(P0.05)was observed between ND and LD *** relative abundance of Proteobacteria generally decreased(by 53.5%–19.7%)across the different degradation levels,while the relative abundance of Cyanobacteria increased(by 6.2%–40.1%)from ND to MD *** abundance,diversity,and community composition of diazotrophs were most strongly related to soil organic carbon,followed by total nitrogen,moisture,and *** least number of network nodes and edges and the lowest density were observed for MD and SD wetlands,indicating that the complexity of free-living diazotrophic networks was reduced by continued ***,severe desert wetland degradation affected the abundance,diversity,and network complexity of soil free-living diazotrophs more negatively than light *** degradation promoted the growth of autotrophic diazotrophs and inhibited the growth of heterotrophic *** changes were mostly related to the loss of soil organic carbon.

关键词： amplicon sequencing biological nitrogen fixation co-occurrence network analysis nifH gene quantitative polymerase chain reaction soil organic carbon

2019年福建省晋江市健康人群破伤风抗体调查

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疾病监测 2020年第6期35卷 523-526页

作者：庄天从张华捷李喆吕新军王传林马霄潘钏愉晋江市罗山街道社区卫生服务中心福建晋江362200 中国食品药品检定研究院北京102629 中国疾病预防控制中心病毒病预防控制所北京100052 北京大学人民医院急诊科国家创伤救治中心北京100044

目的了解福建省晋江市健康人群破伤风抗体(TAB)状况。方法采用分层随机抽样法,采集晋江市2019年各年龄段健康人群血清,通过酶联免疫吸附试验(ELISA)检测血清TAB水平。使用Excel软件整理数据,运用SPSS 22.0软件进行不同组间TAB阳性率差... 详细信息

目的了解福建省晋江市健康人群破伤风抗体(TAB)状况。方法采用分层随机抽样法,采集晋江市2019年各年龄段健康人群血清,通过酶联免疫吸附试验(ELISA)检测血清TAB水平。使用Excel软件整理数据,运用SPSS 22.0软件进行不同组间TAB阳性率差异比较。结果775份调查样本中,TAB总体阳性率为39.2%(304/775),各年龄组TAB阳性率分别为71.9%(87/121,8~20岁)、53.6%(82/153,21~30岁)、39.3%(57/145,31~40岁)、25.2%(38/151,41~50岁)、16.2%(17/105,51~60岁)和23.0%(23/100,61岁以上);有含破伤风类毒素疫苗(TTCV)免疫史人群TAB阳性率为70.7%(164/232),无免疫史或免疫史不明人群TAB阳性率为25.8%(140/543);TAB阴性者从事破伤风高危行业和低危行业的人群,年龄组分布差异有统计学意义(χ^2=62.185;P<0.000);破伤风高危行业人群中40~50岁年龄组比例为46.79%。结论晋江市健康人群TAB阳性率随年龄增长呈下降趋势,应重视开展TTCV的加强免疫工作。

关键词：破伤风破伤风抗体酶联免疫吸附试验含破伤风类毒素疫苗免疫

中国南极海洋生源要素格局及其生态环境效应研究进展

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极地研究 2024年第3期36卷 329-342页

作者：潘建明赵军李栋张海峰于培松张偲杨旭锋朱长凤胡佶扈传昱范高晶韩正兵孙维萍陶柯宇蓝木盛张海生自然资源部海洋生态系统动力学重点实验室自然资源部第二海洋研究所浙江杭州310012 南极长城极地生态国家野外科学观测研究站中国极地研究中心(中国极地研究所)上海200136

南极海洋生源要素格局及其生态环境效应研究是探讨全球气候变化、碳循环和生态系统相互作用的关键内容,也是预测南大洋生态系统演化趋势的重要依据。中国自1984年首次南极科学考察以来,已组织开展多年南大洋综合调查,并依托“南北极环... 详细信息

南极海洋生源要素格局及其生态环境效应研究是探讨全球气候变化、碳循环和生态系统相互作用的关键内容,也是预测南大洋生态系统演化趋势的重要依据。中国自1984年首次南极科学考察以来,已组织开展多年南大洋综合调查,并依托“南北极环境综合考察与评估”和“南极重点海域对气候变化的响应与影响”等极地专项的实施,聚焦南大洋生态系统演变及其环境调控等关键科学问题,取得了一系列重要认识。本文总结了我国在南极海洋生源要素格局及其生态环境效应领域的相关研究进展,特别是海洋生源要素循环与浮游生态系统、生源物质沉降通量及其季节变化以及上层海洋过程的沉积记录等方面的研究成果,初步探讨了南极冰间湖生态过程及其对全球气候变化的响应,并对我国未来南大洋生态环境调查研究提出了相关建议。

关键词：南极海洋生源要素生态环境中国南极科学考察