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丁基自粘TPO防水卷材在金属屋面修缮中的应用

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中国建筑防水 2024年第6期 26-29页

作者：周吉龙深圳市卓宝科技股份有限公司广东深圳518049

某方舱医院项目系利用既有建筑改造而建,原有压型金属板屋面经多年使用,出现锈蚀、变形,致使屋面呈现大面积无规律渗漏。该项目在充分考虑维修工期、造价后,选用在原金属压型板上满粘一层耐候型(TPO)丁基自粘防水卷材,利用TPO片材优异... 详细信息

某方舱医院项目系利用既有建筑改造而建,原有压型金属板屋面经多年使用,出现锈蚀、变形,致使屋面呈现大面积无规律渗漏。该项目在充分考虑维修工期、造价后,选用在原金属压型板上满粘一层耐候型(TPO)丁基自粘防水卷材,利用TPO片材优异的耐候、防水性能实现屋面渗漏治理和长期外露使用的需求。本文介绍了耐候型(TPO)丁基自粘卷材在压型板金属屋面上应用的特点、优势以及施工流程和细部处理。

关键词：压型金属板屋面屋面渗漏修缮丁基自粘胶 TPO片材外露使用

Simulation Research on Stress Intensity Factors of Different Crack Aspect Ratios on Hollow Axles

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Chinese Journal of Mechanical Engineering 2009年第5期22卷 766-771页

作者： zhou Suxia XIE jilong Engineering Research Center of Structure Reliability and Operation Measurement Technology of Rail Guided Vehicles of Ministry of Education Beij＇ing Jiaotong University Beijing 100044 China

Because of the wicked service environment of the high speed train, it is possible that the hollow axle of the train may encounter the foreign object damage and form a sharp notch. Under the fatigue loading a crack can initiate from the notch and propagate to failure. It is noted that the stress intensity factor is the control parameter of the crack propagating, for the purpose of getting the more exact propagation characteristics, the stress intensity factor is studied mainly. The service loads of hollow axles are defined, and the stress distribution of hollow axles is obtained according to the load spectrum. The semi-ellipse crack configuration is defined with three parameters： the aspect ratio, the relative depth and the relative location along the crack front. Quarter point 20-node isoparametric degenerate singular elements are used for the region near the crack tip. The finite element model of crack extension of hollow axle is created, and the crack front is dispersed which can realize orthogonal extension. Based on this the stress intensity factors of crack front were calculated, and the distribution rules of the stress intensity factors of different initial crack shapes are obtained. The conclusions are compared with that of the analytic method and they agree with each other very well, and the calculating results show that there is a close relationship between the stress intensity factor and the initial crack shape. For a round crack the stress intensity factor at the surface point increases faster than the one at the center point with the crock propagation. However, for a narrow crack, the results are in contrast with that of a round one. So, all the cracks with different shapes propagate toward to a similar shape, and they grow at this shape to end. The study may contribute to the crack propagate characteristics research.

关键词： hollow axle surface crack propagation stress intensity factor finite element

高矿化度油藏“强化泡沫+凝胶”调驱实验研究

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西南石油大学学报（自然科学版） 2024年第4期46卷 159-168页

作者：樊晓伊周继龙周永强张金通张迅中国石化河南油田分公司河南南阳473132 河南省提高石油采收率重点实验室河南南阳473000 西南石油大学石油与天然气工程学院四川成都610500

春光油田稀油油藏已经进入高含水、高采出程度和产量递减的开发阶段。针对目前新增储量减少,剩余油分散,挖潜难度大等问题,油田亟需转换新的开发方式,从而进一步挖潜剩余油,实现油田稳产。在春光油田油藏条件下开展了“强化泡沫+凝胶”... 详细信息

春光油田稀油油藏已经进入高含水、高采出程度和产量递减的开发阶段。针对目前新增储量减少,剩余油分散,挖潜难度大等问题,油田亟需转换新的开发方式,从而进一步挖潜剩余油,实现油田稳产。在春光油田油藏条件下开展了“强化泡沫+凝胶”调驱实验研究,对比不同介质驱替结果表明,0.4%P2-1+0.1%温轮胶强化泡沫体系的提高采收率效果远优于单一介质体系。不同介质小段塞多轮次注入实验结果表明,在段塞用量相同时,注入轮次越多,小段塞越多,提高的采收率就相对更高,增加小段塞可以增加段塞体系对油藏的深部非均质调控能力和波及体积,进而提高驱油效率和实现较大幅度提高采收率。

关键词：泡沫凝胶强化泡沐提高采收率介质驱替

Characteristics and influencing factors of CO_(2) emission from inland waters in China

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Science China Earth Sciences 2024年第6期67卷 2034-2055页

作者： Ting zhou Xiaofeng WANG Zuolin XIAO Zhaoyin QING Xianxiang LI jilong WANG Ziyi QUE Chongqing Key Laboratory of Carbon Cycling and Carbon Regulation in Mountainous Ecosystems Chongqing 401331China School of Geography and Tourism Chongqing Normal UniversityChongqing 401331China Chongqing Field Observation and Research Station of Earth Surface Ecological Processes in Three Gorges Reservoir Area Chongqing 405400China School of Earth System Science Tianjin UniversityTianjin 300072China

Inland water bodies,being the most active biogeochemical cycle reactors,play a pivotal role in the global carbon cycle and CO_(2) *** study integrates existing observation dataset of CO_(2) flux(fCO_(2))in rivers,lakes and reservoirs in China,to elucidate their spatial-temporal patterns and key influencing factors and to reappraise the significance for regional carbon *** showed that,the fCO_(2) in rivers,lakes and reservoirs in China presented significant variability with large range of-379.3-4947.6,-160.1-785.0 and -74.0-1603.1 mg CO_(2)m-2h^(-1),*** median of the fCO_(2) in rivers was of 228.5 mg CO_(2)m^(-2)h^(-1),observably higher than these in lakes and reservoirs(26.0 and 28.3 mg CO_(2)m^(-2)h^(-1),respectively).The fCO_(2)in rivers and reservoirs exhibited similar decreasing trend from south to north as a result of universal climate restraint,the averaged fCO_(2) in Pearl River and Yangtze River basins showed much higher than that in Northeastern ***,the averaged fCO_(2) in the Mongolia-Xinjiang lake district and the Northeast lake district were higher than other lake districts,followed by the Qinghai-Xizang lake district,and the Eastern and Yungui lake district were generally low,contradicting the climatic *** water primary production enhancement resulting from human activities was the main driver of spatial variation in the fCO_(2) in ***,the fCO_(2) in rivers presented seasonal pattern with higher wet season than dry season,while opposite patterns were found in lakes and *** temperature,precipitation and water primary production were main ***,it showed pH was a key factor indicating the variability of the fCO_(2) levels either in rivers,lakes or in *** lakes,the fCO_(2) is closely linked to chlorophyll a(Chl-a)and dissolved oxygen(DO),whereas,the fCO_(2) in rivers is primarily associated with organic carbon(OC)and total nitrogen(TN),highlighting the dive

关键词： Rivers/lakes/reservoirs CO_(2) emission Spatio-temporal variability Influence factors Regional contribution

The transcriptional activator Klf5 recruits p300-mediated H3K27ac for maintaining trophoblast stem cell pluripotency

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Journal of Molecular Cell Biology 2023年第7期15卷 31-44页

作者： Chengli Dou Linhui Wu Jingjing Zhang Hainan He Tian Xu Zhisheng Yu Peng Su Xia Zhang Junling Wang Yi-Liang Miao jilong zhou Institute of Stem Cell and Regenerative Biology College of Animal Science and Veterinary MedicineHuazhong Agricultural UniversityWuhan 430070China Key Laboratory of Agricultural Animal Genetics Breeding and Reproduction(Huazhong Agricultural University)Ministry of EducationWuhan 430070China Department of Reproductive Medicine Huangshi Central HospitalAffiliated Hospital of Hubei PolytechnicEdong Healthcare GroupHuangshi 435000China Hubei Hongshan Laboratory Wuhan 430070China

The effective proliferation and differentiation of trophoblast stem cells(TSCs)is indispensable for the development of the placenta,which is the key to maintaining normal fetal growth during ***-like factor 5(Klf5)is implicated in the activation of pluripotency gene expression in embryonic stem cells(ESCs),yet its function in TSCs is poorly ***,we showed that Klf5 knockdown resulted in the downregulation of core TSC-specific genes,consequently causing rapid differentiation of ***,Klf5-depleted embryos lost the ability to establish TSCs in *** the molecular level,Klf5 preferentially occupied the proximal promoter regions and maintained an open chromatin architecture of key TSC-specific *** of Klf5 impaired the enrichment of p300,a major histone acetyl transferase of H3 lysine 27 acetylation(H3K27ac),and further reduced the occupancy of H3K27ac at promoter regions,leading to decreased transcriptional activity of TSC pluripotency ***,our findings highlight a novel mechanism of Klf5 in regulating the self-renewal and differentiation of TSCs and provide a reference for understanding placental development and improving pregnancy rates.

关键词： Klf5 trophoblast stem cells self-renewal chromatin accessibility p300 H3K27ac

Porcine pluripotent stem cells: progress, challenges and prospects

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Frontiers of Agricultural Science and Engineering 2019年第1期6卷 8-27页

作者： Jianyong HAN Yi-Liang MIAO Jinlian HUA Yan LI Xue ZHANG jilong zhou Na LI Ying ZHANG Jinying ZHANG Zhonghua LIU State Key Laboratory for Agrobiotechnology College of Biological Sciences China Agricultural University Institute of Stem Cell and Regenerative Biology/College of Animal Science and Veterinary Medicine/Key Laboratory of Agricultural Animal Genetics Breeding and Reproduction of Ministry of Education Huazhong Agricultural University College of Veterinary Medicine/Shaanxi Centre of Stem Cells Engineering and Technology Northwest A&F University Key Laboratory of Animal Cellular and Genetic Engineering of Heilongjiang Province College of Life Science Northeast Agricultural University

Pluripotent stem cells(PSCs) are characterized by their capacity for high self-renewal and multiple differentiation potential and include embryonic stem cells, embryonic germ cells and induced PSCs. PSCs provide a very suitable model for the studies of human diseases, drugs screening, regenerative medicine and developmental biology research. Pigs are considered as an ideal model for preclinical development of human xenotransplantation, therapeutic approaches and regenerative medicine because of their size and physiological similarity to humans. However, lack of knowledge about the derivation, characterization and pluripotency mechanisms of porcine PSCs hinders progress in these biotechnologies. In this review, we discuss the latest progress on porcine PSCs generation, evaluation criteria for pluripotency, the scienti?c and technical questions arising from these studies. We also introduce our perspectives on porcine PSC research, in the hope of providing new ideas for generating naive porcine PSCs and animal breeding.

关键词： embryonic germ cells embryonic stem cells induced pluripotent stem cells pigs pluripotent stem cells

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畜禽规模养殖污染防治存在问题及解决方案

畜牧兽医科学（电子版） 2019年第11期 59-60页

作者：周纪龙广西省陆川县畜牧站

新时期我国提倡绿色发展模式,强调人与自然和谐相处,畜禽养殖业在带来巨大经济效益的同时,其自身的产业污染也给自然环境带来了巨大的压力。该文通过对养殖污染的危害与原因进行探索,总结发展中存在的污染问题,并对问题的解决方案进行研... 详细信息

新时期我国提倡绿色发展模式,强调人与自然和谐相处,畜禽养殖业在带来巨大经济效益的同时,其自身的产业污染也给自然环境带来了巨大的压力。该文通过对养殖污染的危害与原因进行探索,总结发展中存在的污染问题,并对问题的解决方案进行研究,促进我国绿色发展理念的发展。

关键词：畜禽养殖业规模化养殖污染治理

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耐温耐盐聚合物微球性能评价

油田化学 2016年第2期33卷 254-260页

作者：杨长春岳湘安周代余贺杰赵冀周继龙李超跃中国石油大学(北京)石油工程教育部重点实验室北京102249 中国石油大学(北京)石油工程学院北京102249 中国石油塔里木油田分公司新疆库尔勒841000 西南石油大学化学化工学院四川成都610500

为获得悬浮性好、耐温耐盐性能优良的调剖堵水用聚合物微球,以丙烯酰胺为聚合单体、偶氮二异丁腈为引发剂、二乙烯基苯为交联剂、脂肪醇聚氧乙烯醚硫酸钠为乳化剂合成了具有三层结构的纳米/微米聚合物微球DCA,评价了微球的耐温性、悬浮... 详细信息

为获得悬浮性好、耐温耐盐性能优良的调剖堵水用聚合物微球,以丙烯酰胺为聚合单体、偶氮二异丁腈为引发剂、二乙烯基苯为交联剂、脂肪醇聚氧乙烯醚硫酸钠为乳化剂合成了具有三层结构的纳米/微米聚合物微球DCA,评价了微球的耐温性、悬浮性、膨胀性及调剖堵水效果。结果表明,DCA微球粒径为0.1数30μm,外壳有纳米孔隙,微球耐温高达300℃,可在115℃放置90 d。DCA在模拟地层水中静置28 h的沉降速度为0.005 m L/min,悬浮性较好。DCA微球膨胀率随着温度的升高而升高,在115℃浸泡24 h的最大膨胀率为13.83%;对三层非均质岩心调剖堵水后含水率降低5%,采收率增幅为7%。矿场试验结果表明,经微球段塞调剖后产液量和综合含水率降低、日增油效果明显。DCA微球适用于高温高盐油藏的深部调剖堵水。

关键词：聚合物微球调剖堵水耐温性能抗盐性能高温高盐油藏

一种新型三氮唑化合物的光物理性质及其与血清白蛋白的键合研究

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化学学报 2013年第5期71卷 837-843页

作者：何文英司宏宗栾峰吴禄勇周纪龙何明霞陈光英海南师范大学化学化工学院海口571158 青岛大学计算科学与工程技术研究中心青岛266071 烟台大学化学化工学院烟台264005

1-(1-萘基)-5-苯基-1H-1,2,3-三唑(1-(naphthalen-1-yl)-5-phenyl-1H-1,2,3-triazole,简称NPTA)是一种新合成的三氮唑化合物,研究了其光谱特征及其生物活性.利用PM3半经验方法的Polak-Ribiere共轭梯度法得到了优化的NPTA分子结构,进而用分子对接显示与人血清白蛋白(HSA)的键合模式及位点,再利用紫外光谱、多种荧光光谱法等技术表征了NPTA及其键合HSA的光谱性质.结果表明:共轭多烯π键的存在使得NPTA呈现特征的荧光与紫外光谱.分子模拟的结果表明NPTA可以嵌于HSA分子的疏水腔内,并与精氨酸Arg222形成四个氢键;位点竞争实验确定了NPTA在HSA亚结构域的位点II位发生作用.二维及三维荧光光谱显示NPTA可以猝灭HSA的内源荧光,使其构象发生变化;紫外、同步荧光扫描证实NPTA主要猝灭了HSA色氨酸残基的荧光,并影响了HSA的微环境;较小的各向异性值说明NPTA与HSA结合后生成的配合物弛豫时间较短,结合的较松.荧光滴定法求得不同温度下(299,309和319 K)NPTA与HSA作用的键合常数,键合模式为典型的疏水作用,与分子模拟的结果相一致.另外,测定了NPTA与键合HSA相关的几种物理化学参数.

关键词： NPTA HSA 光谱法键合作用