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机械工程学报 2022年第4期58卷 232-239页

作者：张济民宗振海周和超寇杰同济大学铁道与城市轨道交通研究院上海201804

独立旋转轮对轨道车辆由于左右车轮解除耦合作用,失去了传统刚性轮对所具有的自动复位能力。为改善独立旋转轮对的导向性能,提出一种独立旋转轮对车辆的自适应导向控制方法。该方法可以自动识别车辆是否处于曲线段并且计算曲线半径的大... 详细信息

独立旋转轮对轨道车辆由于左右车轮解除耦合作用,失去了传统刚性轮对所具有的自动复位能力。为改善独立旋转轮对的导向性能,提出一种独立旋转轮对车辆的自适应导向控制方法。该方法可以自动识别车辆是否处于曲线段并且计算曲线半径的大小,针对不同线路状态采取适合的控制策略,实现独立旋转轮轨轨道车辆的运行的自适应控制。在加入自适应控制后,独立旋转车辆恢复了纵向蠕滑力和直线复位对中能力,使独立旋转轮对具备更加优良的导向性能。总体来看,自适应控制下的车辆的曲线导向性能与安全性能均优于独立旋转轮对车辆;在小半径曲线上,自适应控制车辆具备比传统刚性轮对车辆更加优良的曲线导向性能以及安全性能;在曲线半径较大时,由于纵向蠕滑力不足,自适应控制车辆的导向性能要弱于传统刚性轮对车辆。

关键词：独立旋转轮对自适应控制复位性能导向性能安全性

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集中采灌条件下碳酸盐岩热储群井示踪试验

地质学报 2021年第6期95卷 1984-1994页

作者：殷肖肖沈健赵艳婷刘东林赵苏民宗振海天津地热勘查开发设计院天津300250 中国地质调查局水文地质环境地质调查中心河北保定071051

地热回灌是实现地热资源可持续开发的有力措施,在世界各国已获得广泛应用,在地热资源的保护、减少资源浪费、延长地热井寿命以及减少环境污染等方面具有重要意义。天津是我国开展地热回灌比较成熟的地区之一,截至2019年底,天津市基岩裂... 详细信息

地热回灌是实现地热资源可持续开发的有力措施,在世界各国已获得广泛应用,在地热资源的保护、减少资源浪费、延长地热井寿命以及减少环境污染等方面具有重要意义。天津是我国开展地热回灌比较成熟的地区之一,截至2019年底,天津市基岩裂隙型热储回灌率已达79.61%。大规模集中采灌条件下热储层渗流场的变化以及是否会影响热储温度已成为热储系统研究的前沿课题。本文以天津市东丽湖地区为例,选取1,5-萘磺酸钠作为示踪剂,在2018~2019年供暖期集中采灌期间开展了群井示踪试验,结果显示,供暖期内地热井开采量(或回灌量)、水温没有明显变化,水位除受正常采灌影响外没有明显变化,热储系统基本处于稳定状态;试验中示踪剂回收率极低,开采井和回灌井之间水力联系较差,有限的优势通道中的最大流速为448.42m/d,优势通道的方向主要集中于北东向,与区内主要控热断裂沧东断裂及其次生断裂的发育方向一致;在现状开发利用模式下,不会造成该热储层温度的显著变化。这些认识对于指导北方古潜山碳酸盐岩热储的科学开发利用具有一定的现实意义。

关键词：碳酸盐岩热储地热回灌示踪试验优势通道热突破

天津地区地热流体主要离子组分特征及地热成因分析

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华北地质 2023年第2期46卷 9-16页

作者：王冰宗振海夏雨波张芬娜贾志天津地热勘查开发设计院天津300250 中国地质调查局天津地质调查中心天津300170

天津地区中低温地热资源丰富,地热资源开发利用历史悠久,多年的勘查和开发利用取得了丰富的勘查成果。在研究天津地区地质构造和主要热储层地热流体水化学特征的基础上,本文以天津地区大量的地热流体水化学数据为研究对象,选取主要热储... 详细信息

天津地区中低温地热资源丰富,地热资源开发利用历史悠久,多年的勘查和开发利用取得了丰富的勘查成果。在研究天津地区地质构造和主要热储层地热流体水化学特征的基础上,本文以天津地区大量的地热流体水化学数据为研究对象,选取主要热储层地热流体中的主要离子与矿化度之间的关系分别进行R聚类分析和相关分析,结果表明,K+含量在裂隙热储层中普遍高于孔隙型热储,且与矿化度的相关性不高;Na^(+)含量、Ca^(2+)含量与矿化度呈明显的正相关关系,且相关性较高;裂隙热储中地热流体的Cl^(-)、SO_(4)^(2-)含量高于孔隙型热储中的地热流体,且与矿化度呈正相关关系;HCO_(3)^(-)含量则与矿化度关系不大。采用元素比例系数法分析天津地区地热流体特征离子,得知天津地区基岩型地热系统相对比较封闭,有利于地热流体的形成和保存;地热流体属于海相含盐沉积岩溶滤水。综合地热流体水文地球化学、同位素和补给条件等资料分析,天津地区地热水的补给来源为大气降水,入渗水在深循环过程中受到地层围岩的加温过程,并与海相沉积的碳酸盐岩发生溶滤作用,最终形成大气渗入-海相沉积的混合成因溶滤水。

关键词：天津地区地热流体 R聚类分析矿化度元素比例系数法

天津市馆陶组热储集中开采区热储压力恢复原因分析

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华北地质 2024年第2期47卷 54-61页

作者：闫佳贤张森宗振海秦冬时沈健李虎殷肖肖天津地热勘查开发设计院天津300000 天津市地热资源开发有限公司天津300000 自然资源部天津中低温地热野外科学观测研究站天津300000 内蒙古自治区地质调查研究院呼和浩特010000

地热是一种清洁能源,局部集中开采会形成压力降落漏斗。【研究目的】天津地区由于地热开发历史长,形成了大范围压力降落漏斗。2018年开采量逐步减少后,漏斗中心地带的水位开始迅速回升,热储压力开始恢复。但水位回升与开采量变化的相关... 详细信息

地热是一种清洁能源,局部集中开采会形成压力降落漏斗。【研究目的】天津地区由于地热开发历史长,形成了大范围压力降落漏斗。2018年开采量逐步减少后,漏斗中心地带的水位开始迅速回升,热储压力开始恢复。但水位回升与开采量变化的相关关系、漏斗形态会发生哪些变化,目前研究较少,发展规律认识不够清晰。【研究方法】本文以天津地区新近系馆陶组热储层采灌条件下多年水位动态变化特征为例,通过采灌量和水位的相关关系分析,研究漏斗区水位动态演化规律,分析压力恢复的原因,并给出漏斗区地热可采量评价的合理建议。【研究结果】研究认为热储水量持续“入不敷出”是水位降落漏斗形成的根本原因,而群井抽水叠加效应导致热储压力的同步波动,消耗量骤减和漏斗的夷平作用使得漏斗中心区域水位回升。【结论】地热评价和管理应以漏斗区域内热储压力的实时动态为基准,合理控制消耗量,维持水量收支平衡,是地热资源持续利用的有效途径。

关键词：地热资源水位降落漏斗夷平作用天津地区

基于TOUGH2.0东丽湖地区雾迷山组热储资源潜力评价

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工程勘察 2015年第8期43卷 52-57页

作者：刘东林闫佳贤田光辉宗振海蔡芸王冰天津地热勘查开发设计院天津300250

东丽湖地区处在山岭子地热田内,地热资源比较丰富,雾迷山组是该区主要热储层,出水温度最高达102℃。本文在分析东丽湖地区地热地质条件的基础上,考虑了沧东断裂导水导热的作用及大地热流对区域的影响,首次将TOUGH2.0软件平台应用于雾迷... 详细信息

东丽湖地区处在山岭子地热田内,地热资源比较丰富,雾迷山组是该区主要热储层,出水温度最高达102℃。本文在分析东丽湖地区地热地质条件的基础上,考虑了沧东断裂导水导热的作用及大地热流对区域的影响,首次将TOUGH2.0软件平台应用于雾迷山组地热资源可开采潜力评价,计算得出东丽湖地区雾迷山组可新增开采量为515.88×104m3/a,结合区内能源需求,制定科学的开采目标,实现了区域地热资源的可持续利用。

关键词：东丽湖地区 TOUGH2.0 雾迷山组热储潜力评价

Can patients with mild non-neoplastic lesions diagnosed at baseline screening be safely exempt from surveillance: evidence from multicenter community-based cohorts

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Science China Life Sciences 2025年第1期 263-271页

作者： Siyi He Zhiyi Zhang Guohui Song zhenhai Wang Chunyun Dai Shipeng Yan Kun Jiang Bingbing Song He Li Maomao Cao Dianqin Sun Fan Yang Xinxin Yan Shaoli Zhang Yi Teng Qianru Li Changfa Xia Wanqing Chen Office of Cancer Screening National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical College Department of Gastroenterology Gansu Wuwei Tumor Hospital Cixian Cancer Institute Linzhou Cancer Hospital Center for Disease Control and Prevention of Sheyang County Department of Cancer Prevention and Control Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of MedicineCentral South University Luoshan Center for Disease Control and Prevention Office for Cancer Control and Research Affiliated Cancer Hospital of Harbin Medical University

Surveillance recommendations for gastric cancer（GC） in current guidelines focused on advanced precancerous lesions and were based on precise diagnosis of severity/extent of baseline lesions. We aimed to develop a less endoscopy-related equipment-dependent risk-stratification tool, and assessed whether mild-precursor-lesion patients can be safely exempt from surveillance. In the multicenter communitybased cohort, 75,051 participants receiving baseline endoscopy were enrolled during 2015–2017 and followed-up until 2021. Cumulative incidence rates（CIRs） of GC for precancerous-conditions were calculated by Kaplan-Meier method and compared by Log-rank tests. Mixedeffects Cox regression models were used to detect potential factors for progression towards GC. A risk score was calculated as counts of selected factors. An independent cohort, including 26,586 participants was used for external validation. During a median follow-up of 6.25 years, CIRs of GC were 0.302%, 0.436%, and 4.756% for normal group, non-neoplastic（atrophic gastritis/intestinal metaplasia） and neoplastic lesions（low-grade/high-grade dysplasia）, respectively(Ptrend<0.001). Four predictors, including male, ≥60 years, smoking, and limited vegetable consumption, were selected for risk-stratification. High-risk patients（≥3 risk factors） with non-neoplastic lesions showed higher GC risks（adjusted HR=7.73, 95%CI: 4.29–13.92）, and their four-year CIR reached the one-year CIR of neoplastic lesions. Further categorizing non-neoplastic lesions by histological grade, both patients with moderate-to-severe lesions（aHR=3.07, 95%CI: 1.67–5.64） and high-risk patients with mild lesions（aHR=7.29, 95%CI: 3.58–14.86） showed higher risks. Consistent trends were observed in validation cohort. High-risk mild-precursor-lesion patients should receive surveillance within 3–5 years after baseline screening. Our study provides evidence on supplementing current guideline recommendations.

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Structure of a Mixture of Graphene Plates and Ionic Liquid 1-Octyl-3-methylimidazolium Hexafluoroborate

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Chemical Research in Chinese Universities 2018年第4期34卷 598-603页

作者： CHEN Siyan GAO zhenhai State Key Laboratory of Supramolecular Structure and Materials College of Chemistry Jilin University Changchun 130012 P. R.China State Key Laboratory of Automotive Simulation and Control Jilin University Changchun 130025 P. R. China

We reported a molecular dynamics simulation study of a mixture of 1-octyl-3-methylimidazolium hexa- fluoroborate（[C8MIN]^＋[PF6]^-）, an ionic liquid, and pristine graphene. Our simulations were performed under various conditions, including several temperatures and distances between graphene plates. By studying the liquid structure of the ionic-liquid graphene mixture, we found that the transition for the ionic liquids entering the middle of two graphene plates should occur within 1.00 and 1.50 nm in the temperature range studied（300-600 K）. We also studied the pair correlations between the graphene plates and the head and tail of the cation and the anion. Our study at the molecular level can aid in understanding the detailed molecular structure of the mixture.

关键词： Nanofluid Graphene Ionic liquid Molecular dynamic

Strong convergence results for hemivariational inequalities

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Science China Mathematics 2006年第7期49卷 893-901页

作者： LIU zhenhai ZOU Jiezhong Department of Mathematics Changsha University of Science and Technology Changsha 410076 China School of Mathematical Science and Computing Technology Central South University Changsha 410075 China School of Mathematical Science and Computing Technology Central South University Changsha 410075 China

The purpose of this paper is to study a regularization method of solutions of ill-posed problems involving hemivariational inequalities in Banach spaces. Under the assumption that the hemivariational inequality is solvable, a strongly convergent approximation procedure is designed by means of the so-called Browder-Tikhonov regularization method. Our results generalize and extend the previously known theorems.

关键词： hemivariational inequalities, Clarke subdifferential, regularization, strong convergence.

An interfacial engineering strategy of electrocatalyst boosts ammonia electrosynthesis

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Science China Chemistry 2019年第8期62卷 921-922页

作者： Yichun Ding Genxiang Wang zhenhai Wen CAS Key Laboratory of Design and Assembly of Functional Nanostructures Fujian Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of Sciences

Ammonia (NH3) is not only an essential chemical feedstock for the manufacture of nitrogen-rich fertilizers but also a promising carbofree energy carrier for storing H2 due to its high content of hydrogen (17.6% by mass). At present, industrial NH3 is still dominantly produced by the traditional Haber-Bosch process, which reduces nitrogen (N2) to NH3 (N2+3H2←→2NH 3) at high temperatures (350-550 °C) and high pressures (150-350 atm)[1]. Such a process not only requires the raw materials of high-purity streams of nitrogen and hydrogen but also consumes tremendous energy;noting that the consumed hydrogen occupied approximately 50% of its global production that produced exclusively from transformations of fossil resources with the emission of greenhouse gas [1].

关键词： engineering strategy electrosynthesis tremendous energy