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基于DFOS的通州湾地区地面沉降监测与变形分析

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河海大学学报（自然科学版） 2023年第2期51卷 81-88页

作者：卢毅宋泽卓刘瑾卜凡祁长青自然资源部地裂缝地质灾害重点实验室(江苏省地质调查研究院) 江苏南京210049 河海大学地球科学与工程学院江苏南京210098

以江苏省通州湾地区YD002钻孔为研究对象,建立了地面沉降DFOS(distributed fiber optic sensing)系统,对该地区第四纪沉积层的变形及地面沉降进行长期监测,并依据监测数据对该地区地面沉降的现状和趋势进行分析。结果表明:该地区目前的... 详细信息

以江苏省通州湾地区YD002钻孔为研究对象,建立了地面沉降DFOS(distributed fiber optic sensing)系统,对该地区第四纪沉积层的变形及地面沉降进行长期监测,并依据监测数据对该地区地面沉降的现状和趋势进行分析。结果表明:该地区目前的主要变形来源为抽水层上部承压含水层组垂向释水造成的土层压缩变形,地层整体呈压缩趋势,且各压缩层变形与地下水水位变化规律密切相关;相较于传统分层标,DFOS技术能够更加精细化地测量土层垂向的压缩-回弹变形。

关键词：地面沉降 DFOS 沉积层通州湾地区

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若尔盖县湿地稳态转换的水文地貌生态阈值

生态学报 2020年第23期40卷 8794-8804页

作者：崔燚张学霞张雪方宇郭长庆北京林业大学水土保持学院北京100083 水土保持国家林业局重点实验室北京100083

以若尔盖县湿地为研究对象,在Google Earth影像和野外调查基础上获取若尔盖县人工沟渠的空间分布数据,并计算结构特征指数。从地形地貌和水文条件两个方面选择6项指标,利用熵值法筛选出对湿地稳态转换影响最大的指标并厘定生态阈值,包... 详细信息

以若尔盖县湿地为研究对象,在Google Earth影像和野外调查基础上获取若尔盖县人工沟渠的空间分布数据,并计算结构特征指数。从地形地貌和水文条件两个方面选择6项指标,利用熵值法筛选出对湿地稳态转换影响最大的指标并厘定生态阈值,包括理想值和临界值,通过1980—2015年土地利用数据识别若尔盖县湿地稳态转换区,最终基于乡镇尺度确定生态阈值调控范围,划分各乡镇湿地恢复优先性。结果表明:(1)若尔盖县存在四类湿地稳态转换区,其中稳态平衡区面积最大,占全县湿地面积的47.56%,退化转化区次之,占全县湿地面积的35.88%。(2)对若尔盖县湿地稳态转换影响最大的两项水文地貌生态指标为网络联通度和沟渠密度,权重分别为0.162和0.161。若尔盖县网络联通度的理想值为0.033、临界值为0.054;沟渠密度的理想值为0.011 km/km^(2)、临界值为0.360 km/km^(2)。(3)在若尔盖县需要进行湿地恢复的10个乡镇中,按湿地恢复优先性划分出3个三级恢复区、4个二级恢复区、3个一级恢复区,其中一级恢复区应优先恢复。

关键词：生态阈值调控湿地恢复若尔盖县

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中国高速动车组创新发展的探索与实践

铁道技术标准（中英文） 2019年第12期1卷 92-99,104页

作者：刘长青 Wei yi 中车长春轨道客车股份有限公司长春130062 不详

本文通过回顾高速动车组从“技术引进”到“中国制造”再到“中国创造”的创新历程,总结其创新发展取得成就、主要做法和经验启示,为开辟具有中国特色的高速动车组创新发展之路提供参考和借鉴。

关键词：高速动车组创新发展中国创造

Differential Expression of Wnts, β-catenin and E-cadherin in hEFs and Normal, Abnormal Karyotype hES Cells during Culture in vitro

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Journal of Life Sciences 2011年第7期5卷 483-487页

作者： Xueqin Zheng Zhen Xiang Xianlei Li Wenling Lu Li Tan Qingguo Luo changqing He Ye Yu yi Yao yingLi Huaijiang Li Yang Xiang Department of Chemistry and Chemical Engineering Hunan Institute of Science and Technology Yueyang 414000 China

Human embryonic fibroblasts （hEFs） can well maintain the pluripotency in human embryonic stem cells （hESs）. However, recent research and reports indicated that a few of hES cell lines acquired genomic alteration during long-term culture of hES cells in vitro. This will directly restrict the therapy use of hES cells. Wnts are secreted lipid-modified signaling proteins that influence multiple processes ranging from cell proliferation to stem cell loss. Activation of Wnt signaling in many tissues has also been associated with cancer. Unchecked Wnt signaling and loss of cadherin expression can promote tumorigenesis. In this study, we found the caryotype of one hES cell line chHES-3 changed with duplication of 1 p32-1p36 area after 34 passages. The results of RT-PCR indicated Wnt7a was expressed in hEFs after culture normal karyotype hES cells, but not expressed in control and abnormal karyotype hES cells. Wnt3 was expressed in hEFs after culture abnormal karyotype hES cells, not expressed in control and normal karyotype hES cells. Wnt3, Wnt9a and WntlOb were detected weakly expression in normal hES cells, but higher in abnormal hES cells. At the same time, Wnt3a, Wnt4, Wnt5b, Wnt7a, Wnt8b and Wnt11 were expressed and E-cadherin was not tested in abnormal hES cells compared with normal hES cells. All that indicated Wnt7a was need for culture normal karyotype hES cells and Wnt3 was need for culture abnormal karyotype hES cells on hEFs. Wnt3, Wnt9a and WntlOb high expression in hES cells and absence of E-cadherin may cause hES cells karyotype change.

关键词： hEFs hES cell karyotype differential expression Hints β--catenin E-cadherin.

Boosting charge transfer via interface charge reconstruction between amorphous NiFe-LDH and crystalline NiCo_(2)O_(4)for efficient alkaline water/seawater oxidation

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Nano Research 2024年第6期17卷 4856-4863页

作者： Zhonghang Xing yi Zhao Yunhai Wang Xiaohe Liu Zhiqiang Guo Qingyun Chen International Research Center for Renewable Energy and State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049China Department of Environmental Science and Engineering Xi’an Jiaotong UniversityXi’an 710049China China School of Geology and Environment Xi’an University of Science and TechnologyXi’an 710049China changqing Engineering Design Co. Ltd.Xi’an 710018China

Electrocatalysts with optimal efficiency and durability for the oxygen evolution reaction(OER)are becoming increasingly important as the demand for alkaline water/seawater electrolysis technology ***,a novel rose-shaped NiFe-layered double hydroxide(LDH)/NiCo_(2)O_(4)composed of amorphous wrinkled NiFe-LDH and highly crystalline NiCo_(2)O_(4)was synthesized with rich *** unsaturated metal sites are generated due to significant charge reconstruction at the heterointerface between the crystalline and amorphous *** metal sites could trigger and provide more active *** density functional theory(DFT)reveals that a new charge transfer channel(Co-Fe)was formed at the heterointerface between NiFe-LDH as electron acceptor and NiCo_(2)O_(4)as electron *** new charge transfer channel boosts interfacial charge transfer and enhances catalytic *** NiFe-LDH/NiCo_(2)O_(4)/nickel foam(NF)drives current densities of 10 and 100 mA·cm−2 with overpotentials of 193 and 236 mV,*** composite electrode demonstrates a fast turnover frequency(0.0143 s−1)at 1.45 V ***(RHE=reversible hydrogen electrode),which is 5.5 times greater than pure NiCo_(2)O_(4),suggesting its superior intrinsic ***,NiFe-LDH/NiCo_(2)O_(4)/NF electrode exhibited negligible degradation after 150 h of uninterrupted running in alkaline seawater *** study introduces a method for preparing high-efficiency electrocatalysts utilized in alkaline water/seawater electrolysis.

关键词： NiFe-layered double hydroxide(LDH)/NiCo_(2)O_(4)/nickel foam(NF) heterogeneous interfaces charge reconstruction water/seawater electrolysis

A new environmentally friendly water-based drilling fluids with laponite nanoparticles and polysaccharide/polypeptide derivatives

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Petroleum Science 2022年第6期19卷 2959-2968页

作者： Xin-Liang Li Guan-Cheng Jiang yi Xu Zheng-Qiang Deng Kai Wang College of Chemistry and Chemical Engineering Southwest Petroleum UniversityChengdu610500SichuanChina College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China Drilling Fluid Technology Service Corporation CNPC Chuanqing Drilling Engineering Company LimitedChengdu610051SichuanChina changqing General Drilling Company CNPC Chuanqing Drilling Engineering Company LimitedXi’an710018ShaanxiChina

Considering the increasing environmental pressure,environmentally friendly and high-performance water-based drilling fluids(WBDFs)have been widely studied in recent years to replace the commonly used oil-based drilling fluids(OBDFs).However,few of these drilling fluids are entirely composed of natural materials,which makes it difficult to achieve real environmental *** laponite nanoparticles and various derivatives of natu ral mate rials,including cro sslinked starch,cellulose composite,gelatin ammonium salt,poly-l-arginine,and polyanionic cellulose,a kind of environmentally friendly water-based drilling fluid(EF-WBDF)was built for drilling in environment-sensitive *** properties of this EF-WBDF were evaluated by thermal stability tests on rheology,filtration,inhibition,and salt ***,biological toxicity,biodegradability,heavy mental content and wheat cultivation tests were conducted to investigate the environmental factor of *** showed that EF-WBDF displayed satisfactory thermal resistance up to 150℃,and the rheological properties did not suffer significant fluctuation,showing potential application in high-temperature *** optimal rheological model of EF-WBDF was Herschel-Bulkley *** EF-WBDF performed an eligible filtration of 14.2 mL at 150℃and a differential pressure of 3.5 *** fluid could still maintain colloidal stability after being contaminated by 7.5%NaCl or 0.5%CaC1_(2).Meanwhile,rather low clay swelling degree of 2.44 mm and high shale recovery of more than 95%ensured the inhibitive capability of ***,EF-WBDF presented a half maximal effective concentration(EC_(50))of51200 mg/L and a BOD/COD ratio of 47.55%,suggesting that EF-WBDF was non-toxic and easily *** wheat cultivated in EF-WBDF could grow healthily,beneficial for reducing the adverse impact on ecological *** formed EF-WBDF has a promising future for drilling in environment-sensitive and high-te

关键词： Water-based drilling fluids Environmental protection High-temperature resistance Laponite nanoparticles Natural materials Wellbore stability

急诊内镜在急性非静脉曲张性上消化道出血中的诊疗价值

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胃肠病学 2011年第6期16卷 367-369页

作者：龚好仲敏陈怡朱长清上海交通大学医学院附属仁济医院急诊科 200127

急性非静脉曲张性上消化道出血（ANVUGIB）是临床常见急症之一，随着内镜技术的普及，急诊内镜已成为ANVUGIB的首选诊治方法。目的：探讨急诊内镜在ANVUGIB中的诊疗价值。方法：连续纳入2008年1月～2010年7月上海仁济医院确诊的ANVUGIB... 详细信息

急性非静脉曲张性上消化道出血（ANVUGIB）是临床常见急症之一，随着内镜技术的普及，急诊内镜已成为ANVUGIB的首选诊治方法。目的：探讨急诊内镜在ANVUGIB中的诊疗价值。方法：连续纳入2008年1月～2010年7月上海仁济医院确诊的ANVUGIB患者215例．回顾性分析患者的临床资料，比较急诊内镜组（出血48h内行胃镜检查）和择期内镜组（〉48h行胃镜检查）的ANVUGIB病因检出率以及急诊内镜治疗组和内科保守治疗组的止血有效率、再出血率和手术率。结果：消化性溃疡、消化道肿瘤和糜烂出血性胃炎是本组ANVUGIB患者的三大病因，以消化性溃疡最为常见。急诊内镜组的病因检出率显著高于择期内镜组（P〈0．05）；急诊内镜治疗组的止血有效率显著高于内科保守治疗组．再出血率和手术率显著低于内科保守治疗组（P〈0．05）。结论：对ANVUGIB患者，急诊内镜是迅速安全、疗效确切的诊疗方法，值得在临床推广应用。

关键词：内镜检查胃肠道胃肠出血诊断治疗

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一种不稳定硫化体系橡胶材料的制备与性能

高分子材料科学与工程 2018年第11期34卷 120-124页

作者：曹昌庆孙贺雷夏瑞易荣华周爱军武汉工程大学材料科学与工程学院湖北武汉430073

以丁苯橡胶(SBR)为主要基材,纳米氧化锌(Zn O)与硬脂酸(SA)为活性剂,炭黑(CB-774)为补强剂,N-N亚甲基双丙烯酰(MBA)与过氧化二苯甲酰(BPO)为硫化剂,通过机械共混与平板硫化的方法,制备了一种以酰胺键为交联键的不稳定硫化体系的橡胶材... 详细信息

以丁苯橡胶(SBR)为主要基材,纳米氧化锌(Zn O)与硬脂酸(SA)为活性剂,炭黑(CB-774)为补强剂,N-N亚甲基双丙烯酰(MBA)与过氧化二苯甲酰(BPO)为硫化剂,通过机械共混与平板硫化的方法,制备了一种以酰胺键为交联键的不稳定硫化体系的橡胶材料。通过改变MBA用量,研究了橡胶材料的硫化特性、力学性能与老化性能。同时,采用傅里叶变换红外光谱(FT-IR)与扫描电子显微镜(SEM)对橡胶材料的水解特性进行了表征分析。结果表明,当MBA用量为5 phr时,橡胶材料表现出较优的力学性能,其拉伸强度可达到6.3 MPa,断裂伸长率为412.6%,邵尔A硬度为60,且其老化后力学性能损失较小,稳定性保持较好。通过溶解试验发现,橡胶材料经水解后可溶解于有机溶剂中。FT-IR与SEM分析表明,橡胶材料中酰胺交联键在碱性环境下会发生水解,从而导致其产生粗糙的表面结构。

关键词：丁苯橡胶不稳定硫化体系橡胶材料 N,N’-亚甲基双丙烯酰过氧化二苯甲酰

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海藻酸不同存在状态对纳滤膜硅酸盐结垢影响

哈尔滨工业大学学报 2018年第2期50卷 59-64页

作者：李珍贤王磊王佳璇张一职瑞许长青西安建筑科技大学环境与市政工程学院西安710055

为探索硅酸盐结垢过程中,多糖类有机物海藻酸(AA)在纳滤过程中的不同存在状态,即在溶液中与饱和硅酸盐共存、在膜面生成有机污染层,对聚酰胺复合纳滤膜硅酸盐结垢的影响.由过滤实验研究硅酸盐结垢过程中膜通量衰减趋势;结合扫描电子显... 详细信息

为探索硅酸盐结垢过程中,多糖类有机物海藻酸(AA)在纳滤过程中的不同存在状态,即在溶液中与饱和硅酸盐共存、在膜面生成有机污染层,对聚酰胺复合纳滤膜硅酸盐结垢的影响.由过滤实验研究硅酸盐结垢过程中膜通量衰减趋势;结合扫描电子显微镜及原子力显微镜,分析膜表面污染层结构;通过Zeta电位研究静电排斥作用的影响;利用原子力显微镜结合二氧化硅胶体探针分析不同结垢阶段的黏附力特点.结果表明:硅酸盐结垢污染程度为:新膜>AA与硅酸盐共存时(新膜)>AA污染膜.对比新膜的硅酸盐结垢,AA与硅酸盐共存时,可以较弱程度地减轻硅酸盐结垢;然而当AA污染层在膜面形成后,硅酸盐结垢程度显著降低.上述结果表明,AA的不同存在状态对硅酸盐结垢的影响差异很大.

关键词：海藻酸硅酸盐聚酰胺复合纳滤膜原子力显微镜黏附力