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An integrated north–south paleo-Dadu-Anning River: New insights from bulk major and trace element analyses of the Xigeda Formation

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China Geology 2024年第1期7卷 91-103页

作者： Yong Zheng Hai-bing Li Jia-wei Pan Ping Wang ya lai Zheng Gong Key Laboratory of Deep-Earth Dynamics Institute of GeologyChinese Academy of Geological SciencesChina Geological SurveyMinistry of Natural ResourcesBeijing 100037China Jiangsu Donghai Continental Deep Hole Crustal Activity National Observaion and Research Station Lianyungang 222300China Southern Marine Science and Engineering Guangdong Laboratory Guangzhou 511458China Geophysical Exploration Center China Earthquake AdministrationZhengzhou 450002China Institute of Geophysics China Earthquake AdministrationBeijing 100081China

The Xianshuihe-Anninghe fault extends SE–S and constitutes the southeastern margin of the Tibetan ***,the Dadu River which is associated with the fault does not flow following the path,but makes a 90ºturn within a distance of 1 km at Shimian,heading east,and joins the yangtze River,finally flowing into the East China *** to the abrupt turn,a low and wide pass near the Daqiao reservoir at Mianning separates the N–S course of the Dadu River from the headwater of the Anning River which then flows south into the Yunnan Province along the Anninghe ***,many previous studies assumed southward flow of the paleo-Dadu River from the Shimian to the Anning ***,evidences for the capture of the integrated N–S paleo-Dadu-Anning River,its timing,and causes are still *** study explored the paleo-drainage pattern of the Dadu and Anning Rivers based on bulk mineral and geochemical analyses of the large quantities of fluvial/lacustrine sediments along the trunk of the Dadu and Anning *** with sands in the modern Dadu River,the Xigeda sediments also exhibit a granitoid affinity with the bulk major mineral compositions of quartz(>50%),anorthite(about 10%),orthoclase(about 5%),muscovite(about 5%),and clinochlore(about 4%).Correspondingly,bulk major elements show high SiO_(2),with all samples>60%,and some of them>70%,low TiO_(2)(≤0.75%),P_(2)O_(5)(≤0.55%),FeO*(≤5%),and relatively high CaO(1.02%–8.51%),Na_(2)O(1.60%–2.52%),and K_(2)O(2.17%–2.71%),with a uniform REE ***,synthesizing all these results indicate that these lacustrine sediments have similar material sources,which are mainly derived from its course in the Songpan-Ganzi flysch block,implying that the paleo-Dadu originally flowed southward into the Anning River and provided materials to the Xigeda ancient *** rearrangement of the paleo-Dadu River appears to be closely related to the locally focused uplift driven by strong activities of the Xians

关键词： Dadu River Anninghe fault River diversion Xigeda Formation Tectonic uplift Provenance Songpan-Ganzi flysch Ancient lake Xianshuihe-Xiaojiang fault system Tibetan Plateau

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数字图集:社交媒体中的数字记忆与遗忘

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现代传播（中国传媒大学学报） 2024年第6期46卷 78-84页

作者：詹琰赖雅芊中国科学院大学人文学院南安普顿大学艺术与人文学院

在社交媒体平台上,数字图像往往以多图并置的方式呈现,成为记录与塑造数字记忆的重要形式。数字图集能够突破数字记忆中记住与遗忘的二元对立,打破遗忘被排除于数字记忆之外的理论困境,构造出潜藏遗忘可能性的数字记忆。数字图集的独特... 详细信息

在社交媒体平台上,数字图像往往以多图并置的方式呈现,成为记录与塑造数字记忆的重要形式。数字图集能够突破数字记忆中记住与遗忘的二元对立,打破遗忘被排除于数字记忆之外的理论困境,构造出潜藏遗忘可能性的数字记忆。数字图集的独特性来源于其形式特征和活动方式。数字图集依赖图像形式中的空间蒙太奇,社交平台上复制、转发数字图集的活动,以及数字图集构造数字记忆的动态结构,形成既保存与传递信息,又经由信息衰退和消失等遗忘方式共同塑造数字记忆的动态结构。

关键词：数字图集复数性数字记忆遗忘

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高温-冷却-冲击循环下花岗岩物理损伤及力学劣化试验研究

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岩土力学 2024年第8期45卷 2362-2372,2386页

作者：詹金武周亚来王雨黄明江松福建理工大学土木工程学院福建福州350118 聊城大学建筑工程学院山东聊城252059 福州大学土木工程学院福建福州350116

高温岩石经不同冷却方式冷却后的力学特性直接影响着深地岩土工程施工的安全性。以中风化花岗斑岩为研究对象,对400℃下循环自然冷却和遇水冷却试样展开单轴压缩试验和循环动态冲击试验,对比分析花岗岩力学性质的变化规律,并基于Logisti... 详细信息

高温岩石经不同冷却方式冷却后的力学特性直接影响着深地岩土工程施工的安全性。以中风化花岗斑岩为研究对象,对400℃下循环自然冷却和遇水冷却试样展开单轴压缩试验和循环动态冲击试验,对比分析花岗岩力学性质的变化规律,并基于Logistic分布规律,引入受荷损伤变量和热循环损伤变量建立花岗岩统计损伤本构模型,确定了相应参数表达式,验证了本构模型的适用性与合理性,结果表明:在单轴压缩试验中,随着热循环次数的提高,花岗岩内部微裂隙开始扩展、贯通形成宏观裂纹,岩样质量和纵波波速开始衰减,静态应力-应变曲线中的弹性变形阶段逐渐缩短,出现明显的不稳定破坏阶段;冷却方式可以显著影响岩石强度的劣化速度,但对花岗岩的最终静态抗压强度无明显影响。在0.30 MPa冲击气压下,随着冲击次数的增加,自然冷却花岗岩的动态抗压强度先增大后减小,首次冲击可有助于提高自然冷却花岗岩的抗压强度,当热循环超过3次时,花岗岩的抗循环冲击能力开始下降。基于Logistic分布建立的动态损伤本构模型与试验曲线具有较好的一致性,且模型参数获取简单,物理意义明确,具有一定适用性。研究成果可为变温环境下岩体施工、修复及围岩稳定性分析提供参考。

关键词：高温岩石自然冷却遇水冷却多次冲击损伤程度

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Selective separation of pyrene from mixed polycyclic aromatic hydrocarbons by a hexahedral metal-organic cage

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Chinese Chemical Letters 2024年第1期35卷 523-527页

作者： ya-Liang lai Juan Su Le-Xiong Wu Dong Luo Xue-Zhi Wang Xian-Chao Zhou Chuang-Wei Zhou Xiao-Ping Zhou Dan Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and ApplicationsJinan UniversityGuangzhou 510632China

Polycyclic aromatic hydrocarbons(PAHs)play an important role in the industry,and the development of new materials for the selective separation of PAHs is of great *** this work,we report a hexahedral metal-organic cage with low symmetry by subcomponent *** this cage,the eight ZnII centers adopt an interestin∧∧/△△△△△△or∧∧∧∧∧∧/△△*** cage with a cavity volume of 520˚A3 can bind anthracene,phenanthrene,and pyrene to form 1:1 host-guest complexes,while the bigger triphenylene,chrysene,perylene,and coronene cannot be *** binding constant Ka of pyrene is about 1.110×10^(3)(mol/L)^(−1),which is more than an order of magnitude larger than that of anthracene and phenanthrene(111(mol/L)^(−1),277(mol/L)^(−1),respectively).X-ray structure studies reveal that the pyrene is located in the cavity and stabilized by multiple C–H…π*** separation from a mixture of PAHs,pyrene with>96.1%purity can be *** work provides a useful method for the first time for the selective separation of pyrene from PAHs mixture by utilizing a metal-organic cage as the material,making it a useful tool for purifying and separating specific compounds from complex mixtures.

关键词： Polycyclic aromatic hydrocarbons Metal-organic cage Host-guest chemistry Selective separation

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大跨径上承空腹式梁拱组合刚构桥设计关键技术

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公路交通科技 2024年第5期41卷 69-78页

作者：赖亚平闫福成杨丁重庆大学土木工程学院重庆400045 林同棪国际工程咨询(中国)有限公司重庆401121

为克服主跨大于200 m的山区桥梁在桥型选择中采用连续刚构桥易导致的弊端,以及选用上承式钢筋混凝土拱桥由于适用条件存在的局限性,提出了将常规预应力混凝土连续刚构桥和上承式钢筋混凝土拱桥在结构体系上进行组合,形成上承式梁拱组合... 详细信息

为克服主跨大于200 m的山区桥梁在桥型选择中采用连续刚构桥易导致的弊端,以及选用上承式钢筋混凝土拱桥由于适用条件存在的局限性,提出了将常规预应力混凝土连续刚构桥和上承式钢筋混凝土拱桥在结构体系上进行组合,形成上承式梁拱组合刚构新桥型。大跨径上承空腹式梁拱组合刚构桥的结构体系和力学特征进行了分析,采用有限元分析方法对该桥型的主要结构参数、合理成桥状态、拱梁汇合段构造、梁拱倒三角区施工和临时扣索的合理拆除时机等设计关键技术开展研究,结果表明:上承空腹式梁拱组合刚构桥利用下弦拱辅助主梁受力并形成自平衡受力体系,显著减小了中跨和边跨主梁长度,使结构力学性能得以优化,具有结构竖向刚度大,对长期挠度变形控制效果好的优点;当结构关键控制点的强度、刚度和线形计算指标符合目标范围时,可达到合理成桥状态;拱梁汇合段的下弦拱顶板与上弦梁底板的交汇构造采用A字形,构造简单,传力效果好,施工质量容易控制;该桥型适宜采用平衡悬浇节段施工,梁拱倒三角区段上弦梁和下弦拱均需采用临时斜拉扣挂辅助结构受力,下弦拱临时扣索宜在拱梁汇合段形成后与中跨常规梁段跨中合龙之前分批拆除,上弦梁临时扣索在全桥合龙后拆除。

关键词：桥梁工程组合结构体系有限元分析设计关键技术合理成桥状态施工方法临时斜拉扣挂

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温阳活血法预防妇科恶性肿瘤术后下肢深静脉血栓形成的临床疗效观察

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中医肿瘤学杂志 2024年第4期6卷 34-40页

作者：赖雅薇潘海霞李凯月李道成周英广州中医药大学第一临床医学院广东广州510405 广州中医药大学第一附属医院广东广州510405 广东省中医临床研究院广东广州510405

目的评估温阳活血法预防妇科恶性肿瘤术后下肢深静脉血栓(Deep vein thrombosis,DVT)形成的临床效果及安全性。方法采用回顾性分析,纳入2023年5月至2023年12月在广州中医药大学第一附属医院接受妇科恶性肿瘤手术治疗的85例患者。根据术... 详细信息

目的评估温阳活血法预防妇科恶性肿瘤术后下肢深静脉血栓(Deep vein thrombosis,DVT)形成的临床效果及安全性。方法采用回顾性分析,纳入2023年5月至2023年12月在广州中医药大学第一附属医院接受妇科恶性肿瘤手术治疗的85例患者。根据术后预防方法的不同,分为温阳防栓方组(64例)和低分子肝素组(21例)。比较两组术后DVT发生率,以及术后第1、3、7天D-二聚体(D-Dimer,D-D)及血小板水平。结果术后DVT发生率方面,温阳防栓方组低于低分子肝素组(9.38%vs 19.05%),但差异无统计学意义(P>0.05);D-D方面,温阳防栓方组术后第1天明显低于低分子肝素组(P0.05);不良事件方面,温阳防栓方组发生率更低(肝功能受损率:12.5%vs 38.1%),差异有统计学意义(P<0.05)。结论温阳防栓方在预防妇科恶性肿瘤术后DVT形成方面效果优于低分子肝素,且不良反应较少。

关键词：温阳活血法下肢深静脉血栓妇科恶性肿瘤中药外治回顾性研究

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Achieving High CO_(2)Photoreduction Activity by Conductive Crosslinks of Metal–Organic Framework

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CCS Chemistry 2024年第5期6卷 1211-1221页

作者： Ning Li Gui-Qi lai lai-Hon Chung Fei Yu Jun He ya-Qian Lan Department School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhouGuangdong 510006 School of Chemistry South China Normal UniversityGuangzhou 510006 School of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023

Fast photogenerated charge migration is crucial for the improvement of photocatalytic performance,but its deliberate modulation is *** work presents two Zr-based metal–organic framework catalysts,GDUT-8 and GDUT-8-Ox,for photocatalytic CO_(2)***,thiophene pendants in GDUT-8 were coupled covalently via Scholl reaction to give GDUT-8-Ox,a catalyst with at least two orders of magnitude(up to 6.1×10^(−3)S cm^(−1))enhanced conductivity and faster transport of photogenerated carriers during ***,from GDUT-8 to GDUT-8-Ox,stronger ligand-to-cluster charge transfer with pronounced light absorption extension was *** a result,GDUT-8-Ox exhibited the highest photocatalytic CO_(2)-to-HCOO−conversion rate(1725μmol g^(−1)h^(−1))to date,in the absence of photosensitizer,as well as turnover number,turnover frequency,and quantum efficiency much higher than *** work presents an unprecedented strategy to accelerate the photogenerated carrier transport of photocatalysts.

关键词： metal-organic framework Scholl reaction covalent crosslinks high conductivity CO_(2)photoreduction CO_(2)-to-HCOO−conversion

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Health risk assessment of heavy metals in soils and crops in a mining area(Au-Ag-Cutrona-oil et al.) of the Nanyang Basin, Henan Province, China

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China Geology 2023年第4期6卷 567-579页

作者： Qiu-yao Dong Hao-tian Wen Pan Wang Chao Song Shu-ya lai Zhen-jing yang Yuan-yi Zhao Ming-jiang yan Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Key Laboratory of Quaternary Chronology and Hydro-Environmental Evolution China Geological SurveyMinistry of Natural ResourcesShijiazhuang 050061China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China School of Earth Sciences Hebei GEO UniversityShijiazhuang 050031China Institute of Mineral Resources Chinese Academy of Geological SciencesBeijing 100037China

Heavy metal distribution in mining areas has always been a hot research topic due to the special environment of these areas. This study aims to explore the impact of heavy metal pollution on soils and crops in the study area, ensure the safety of local crops and the health of local residents, and provide a basis for the subsequent environmental restoration and the prevention and control of environmental pollution. Based on the analysis of the heavy metal concentrations in local soils and crops, the study investigated the spatial distribution, pollution degrees, and potential ecological risks of heavy metals in the farmland of a mining area in the southeastern Nanyang Basin, Henan province, China explored the sources of heavy metals and assessed the health risks caused by crop intake. The results of this study are as follows. The root soils of crops in the study area suffered heavy metal pollution to varying degrees. The degree of heavy metal pollution in maize fields is higher than that in wheat fields, and both types of fields suffer the most severe Cd pollution. Moreover, the root soils of different crops suffer compound *** root soils in the maize fields suffer severe compound pollution at some sampling positions, whose distribution is similar to that of the mining area. Cd poses the highest potential ecological risks among all heavy metals, and the study area mainly suffers low and moderate comprehensive potential ecological risks. The principal component analysis(PCA) shows that the distribution of Zn, Cd, Pb, and As in soils of the study area is mainly affected by anthropogenic factors such as local mining activities;the distribution of Cr and Ni is primarily controlled by the local geological background;the distribution of Hg is mainly affected by local vehicle exhaust emissions, and the distribution of Cu is influenced by both human activities and the geological background. Different cereal crops in the study area are polluted with heavy metals dom

关键词： Heavy metal Zn-Cd-Pb pollution Cr-Ni pollution As pollution Natural ecosystem Health risk assessment Adult-children health risk Ecological risk index(ERI) Ecological geological engineering Mining activity

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Fetal Hemodynamics and Fetal Growth Indices by Ultrasound in Late Pregnancy and Birth Weight in Gestational Diabetes Mellitus

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Chinese Medical Journal 2016年第17期129卷 2109-2114页

作者： Fang Liu Yong Liu ya-Ping lai Xiao-Ning Gu Dong-Mei Liu Min yang Department of Ultrasound Beijing Shijitan Hospital Affiliated to Capital Medical University Beijing 100038 China Department of Obstetrics and GynecologY Beijing Shijitan Hospital Affiliated to Capital Medical Llniversity Beijing 100038 China

Background： The offspring of women with gestational diabetes mellitus （GDM） are prone to macrosomia. However, birth weight is difficult to be correctly estimated by ultrasound because of fetal asymmetric growth characteristics. This study aimed to investigate the correlations between fetal hemodynamics, fetal growth indices in late pregnancy, and birth weight in GDM. Methods： A total of 147 women with GDM and 124 normal controls （NC） were enrolled in this study. Fetal hemodynamic indices, including the systolic/diastolic ratio （S/D）, resistance index （RI）, pulsatility index （PI） of umbilical artery （UA）, middle cerebral artery （MCA）, and renal artery （RA）, were collected. Fetal growth indices, including biparietal diameter （BPD）, head circumference （HC）, abdominal circumference （AC）, and femur length, were also measured by ultrasound. Birth weight, newborn gender, and maternal clinical data were collected. Results： The independent samples t-test showed that BPD, HC, and AC were larger in GDM than in NC （P 〈 0.05）. Fetal hemodynamic indices of the UA and MCA were lower （P 〈 0.05）, but those of the RA were higher （P 〈 0.001 ） in GDM than in NC. Birth weight was higher in GDM than in NC （P 〈 0.001）. Pearson＇s correlation analysis showed that hemodynamic indices of the UA were negatively correlated with birth weight, BPD, HC, and AC in both groups （P 〈 0.05）. MCA （S/D, PI, and RI） was negatively correlated with birth weight, HC, and AC in GDM （i- = -0.164, -0.206, -0.200, -0.226, -0.189, -0.179, -0.196, -0.177, and - 0.172, respectively, P 〈 0.05）, but there were no correlations in NC （P 〉 0.05）. RA （S/D, PI, and RI） was positively correlated with birth weight in GDM （r = 0.168, 0.207, and 0.184, respectively, P 〈 0.05）, but there were no correlations in NC （P 〉 0.05）. Conclusion： Fetal hemodynamic indices in late pregnancy might be helpful for estimating newborn birth weight in women with GDM.

关键词： Fetus Gestational Diabetes Mellitus Infant Middle Cerebral Artery Renal Artery Ultrasound Umbilical Artery

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Trends in etiologies of chronic pancreatitis within 20 years： analysis of 636 cases

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Chinese Medical Journal 2011年第21期124卷 3556-3559页

作者： LI Jing-nan lai ya-min QIAN Jia-ming GUO Tao LU Hong TANG Xiao-yan Department of Gastroenterology Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing 100730 China

Background The prevalence of chronic pancreatitis has increased during recent years in Asia-Pacific areas as well as in China. The etiologies vary in different regions and periods. This study aimed to investigate the changing etiologies of chronic pancreatitis within 20 years at Peking Union Medical College Hospital in China. Methods Retrospective analysis of the etiologies of 636 cases of chronic pancreatitis at Peking Union Medical College Hospital from 1990 to 2010 was performed. Patients were divided into two groups according to two time periods （1990-2000 and 2001-2010）. Statistical analysis was performed using the chi-square test. Results The morbidity rate of chronic pancreatitis in China has recently increased. The main etiology changed from biliary diseases in the 1990s （decreased from 36.8% to 28.1%） to alcohol abuse after the year 2000 （increased from 26.5% to 36,8%）. The main etiology of biliary diseases is stones in the cholecyst or bile duct, and the percentage of choLecystitis cases has increased. Autoimmune disease, inctuding autoimmune pancreatitis, has increased quickly and currently accounts for 7.3% of cases because a greater number of autoimmune pancreatitis cases are being diagnosed. Approximately 9.5% of chronic pancreatitis cases are caused by multiple factors such as alcohol abuse and bile duct stones. Other factors include cholecystectomy and acute pancreatitis. Conclusions The main etiology of chronic pancreatitis has changed from biliary disease to alcohol abuse in recent years. Autoimmune factors have also obviously increased.

关键词： chronic pancreatitis etiology bile duct disease autoimmune pancreatitis

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