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随机裂隙围岩盾构隧道注浆浆液扩散规律

铁道工程学报 2024年第9期41卷 67-71,76页

作者：王新强中国铁建大桥工程局集团有限公司天津300300

研究目的:盾构隧道同步注浆是造成施工期管片上浮、错台的主要因素,尤其是在自稳能力较差与裂隙较多的地层。为探究同步注浆浆液在盾尾间隙与围岩的填充与扩散规律,本文以广州地铁18号线为背景,建立考虑围岩随机裂隙分布的浆液渗透瞬态... 详细信息

研究目的:盾构隧道同步注浆是造成施工期管片上浮、错台的主要因素,尤其是在自稳能力较差与裂隙较多的地层。为探究同步注浆浆液在盾尾间隙与围岩的填充与扩散规律,本文以广州地铁18号线为背景,建立考虑围岩随机裂隙分布的浆液渗透瞬态模型,以期为盾构隧道同步注浆过程提供一定的理论指导。研究结论:(1)浆液在注浆后20 s内可以完全填充盾尾间隙,随后浆液会随着裂隙向地层中填充渗透,渗透速度随时间不断降低;(2)因注浆压力的存在,使得管片周围地层的孔隙水压力明显大于远离隧道区域相同埋深的地层;(3)裂隙中的达西速度明显大于连续地层,贯通裂隙几乎是地下水流通的唯一通道;(4)地层中的达西速度对地层的孔隙率以及渗透系数较为敏感;(5)本研究成果可应用于盾构隧道注浆工程领域。

关键词：地铁隧道同步注浆随机裂隙浆液扩散瞬态模型

Reconstructing coherent dynamics of bound states induced by strong attosecond XUV pulses

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Chinese Optics Letters 2024年第2期22卷 56-63页

作者：贾利娟刘明清王新强徐龙闫培光姜维超傅立斌 Institute of Quantum Precision Measurement College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China Department of Physics Xiamen UniversityXiamen 361005China Graduate School of China Academy of Engineering Physics Beijing 100193China

We propose a scheme that utilizes weak-field-induced quantum beats to investigate the electronic coherences of atoms driven by a strong attosecond extreme ultraviolet(XUV)*** technique involves using a strong XUV pump pulse to excite and ionize atoms and a time-delayed weak short pulse to probe the photoelectron *** theoretical analysis demonstrates that the information regarding the bound states,initiated by the strong pump pulse,can be precisely reconstructed from the weak-field-induced quantum beat *** examine this scheme,we apply it to the attosecond XUV laser-induced ionization of hydrogen atoms by solving a three-dimensional time-dependent Schr?dinger *** work provides an essential reference for reconstructing the ultrafast dynamics of bound states induced by strong XUV attosecond pulses.

关键词： attosecond pulse bound-state dynamics quantum beats

Progress in efficient doping of Al-rich AlGaN

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Journal of Semiconductors 2024年第2期45卷 10-20页

作者： Jiaming wang Fujun Xu Lisheng Zhang Jing Lang Xuzhou Fang Ziyao Zhang Xueqi Guo Chen Ji Chengzhi Ji Fuyun Tan Xuelin Yang Xiangning Kang Zhixin Qin Ning Tang xinqiang wang Weikun Ge Bo Shen State Key Laboratory of Artificial Microstructure and Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871China Beijing SinoGaN Semiconductor Technology Co. Ltd.Beijing 101399China Nano-optoelectronics Frontier Center of Ministry of Education Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China

The development of semiconductors is always accompanied by the progress in controllable doping *** AlGaN-based ultraviolet(UV)emitters as an example,despite a peak wall-plug efficiency of 15.3%at the wavelength of 275 nm,there is still a huge gap in comparison with GaN-based visible light-emitting diodes(LEDs),mainly attributed to the inefficient doping of AlGaN with increase of the Al ***,p-doping of Al-rich AlGaN is a long-standing challenge and the low hole concentration seriously restricts the carrier injection *** p-GaN cladding layers are widely adopted as a compromise,the high injection barrier of holes as well as the inevitable loss of light extraction cannot be *** in terms of n-doping the main issue is the degradation of the electrical property when the Al composition exceeds 80%,resulting in a low electrical efficiency in sub-250 nm *** review summarizes the recent advances and outlines the major challenges in the efficient doping of Al-rich AlGaN,meanwhile the corresponding approaches pursued to overcome the doping issues are discussed in detail.

关键词： AlGaN-based UV-LEDs Al-rich AlGaN doping

New U-Pb age constraints on the upper Banxi Group and synchrony of the Sturtian glaciation in South China

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Geoscience Frontiers 2017年第5期8卷 1161-1173页

作者： Gaoyuan Song xinqiang wang Xiaoying Shi Ganqing Jiang School of Earth Science and Resources China University of Geosciences (Beijing) Beijing 100083 China State Key Laboratory of Biogeology and Environmental Geology Beijing 100083 China Department of Geoscience University of Nevada Las Vegas NV 89154-4010 USA

The Nanhua basin in South China hosts well-preserved middle-late Neoproterozoic sedimentary and volcanic rocks that are critical for studying the basin evolution, the breakup of the supercontinent Rodinia, the nature and dynamics of the "snowball" Earth and diversification of metazoans. Establishing a stratigraphic framework is crucial for better understanding the interactions between tectonic, paleoclimatic and biotic events recorded in the Nanhua basin, but existing stratigraphic correlations remain debated, particularly for pre-Ediacaran strata. Here we report new Laser Ablation Inductively Coupled Plasma Mass Spectrometry(LA-ICPMS) U-Pb zircon ages from the middle and topmost Wuqiangxi Formation(the upper stratigraphic unit of the Banxi Group) in Siduping, Hunan Province, South China. Two samples show similar age distribution, with two major peaks at ca. 820 Ma and 780 Ma and one minor peak at ca. 910 Ma, suggesting that the Wuqiangxi sandstone was mainly sourced from Neoproterozoic rocks. Two major age peaks correspond to two phases of magmatic events associated with the rifting of the Nanhua basin, and the minor peak at ca. 910 Ma may correspond to the Shuangxiwu volcanic arc magmatism, which represents pre-collision/amalgamation subduction on the southeastern margin of the Yangtze Block. The youngest zircon group from the topmost Wuqiangxi Formation has a weighted mean age of 714.6±5.2 Ma, which is likely close to the depositional age of the uppermost Banxi Group. This age, along with the ages reported from other sections, constrains that the Banxi Group was deposited between ca. 820 Ma and ca. 715 Ma. The age of 714.6±5.2 Ma from the top of the Wuqiangxi Formation is indistinguishable with the SIMS U-Pb age of 715.9± 2.8 Ma from the upper Gongdong Formation in the Sibao village section of northern Guangxi, South China. It is also, within uncertainties, overlapped with two TIMS U-Pb ages from pre-Sturtian strata in Oman and Canada. These ages indicate that th

关键词： Nanhua basin Wuqiangxi Formation Banxi Group U-Pb zircon ages Sturtian glaciation South China

Chemocline instability and isotope variations of the Ediacaran Doushantuo basin in South China

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Science China Earth Sciences 2008年第11期51卷 1560-1569页

作者： JIANG GanQing ZHANG ShiHong SHI XiaoYing wang xinqiang Department of Geoscience University of NevadaLas VegasNV 89154-4010USA School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China State Key Laboratory of Geological Process and Mineral Resources Beijing 100083China

Stable isotope analyses in sections across a shelf to basinal transect of the Ediacaran Doushantuo basin show substantial isotope variabilities. In Songlin section where sediments were deposited in an intrashelf basin, δ 13C values are persistently negative (_3‰ to _5‰, VPDB) through the entire Doushantuo Formation, similar to those obtained from the slope section in Wuhe (_5‰ to _10‰, VPDB). Shallow water sections in Weng'an and Duoding show two broad δ 13C anomalies overprinted with significant meter-scale variations, but none of the curves has similar absolute δ 13C values compared to the Yangtze Gorges areas in South China and other sections globally. Such isotope variations, if partially recording ancient seawater signature, imply spatial and temporal chemocline instability in the Doushantuo basin. In combination with available δ 13C records from other Ediacaran successions globally, the data from the Doushantuo basin are consistent, in first order, with the existence and oxidation of a large dissolved organic carbon (DOC) reservoir in Ediacaran oceans, but imply local environmental controls on Neoproterozoic isotope values and call attentions for using δ 13C anomalies as time lines in stratigraphic correlation.

关键词： Ediacaran isotopes chemocline early animals Doushantuo Formation South China

择偶优劣势对师范大学生教师职业认同的影响:择偶价值感的中介及自尊的调节作用

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心理发展与教育 2024年第1期40卷 64-73页

作者：王鑫强李金文卢红燕赖正伟李佳源江西师范大学心理学院心理健康教育研究中心南昌330022 北京师范大学发展心理研究院北京100875 爱丁堡大学社会科学健康学院英国爱丁堡EH89AG 新疆师范大学心理学院乌鲁木齐830017 四川外国语大学国际教育学院重庆400031

采用情境故事法启动基于职业资源的择偶优劣势,以567师范大学生为有效被试,考察择偶优劣势对师范大学生教师职业认同的影响,并分析择偶价值感和自尊在该影响中的中介作用和调节作用。结果发现:(1)择偶优劣势显著影响了师范大学生的职业... 详细信息

采用情境故事法启动基于职业资源的择偶优劣势,以567师范大学生为有效被试,考察择偶优劣势对师范大学生教师职业认同的影响,并分析择偶价值感和自尊在该影响中的中介作用和调节作用。结果发现:(1)择偶优劣势显著影响了师范大学生的职业价值和外在价值认同,但对职业认同总分及其他维度(职业意愿与期望、职业意志、职业效能、内在价值认同、意志行为认同)的影响不显著;(2)择偶优劣势通过择偶价值感的中介作用影响外在价值认同,自尊调节该中介模型的前半段路径,高自尊个体的择偶价值感受择偶优劣势的影响相对较小;(3)随着自尊水平的下降,择偶价值感在择偶优劣势对外在价值认同影响中的中介效应随之增大。研究为教师职业认同的提升工作提供了理论指导。

关键词：教师职业认同择偶优劣势择偶价值感职业价值认同自尊

A New Convergent Algorithm for Online Empirical Risk Minimization

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A New Convergent Algorithm for Online Empirical Risk Minimiz...

基于网络药理学和实验验证探讨当归黄芪超滤物治疗放射性心肌纤维化的作用机制

第36届中国控制会议

作者： xinqiang wang Lei Guo Key Lab.of Systems and Control Institute of Systems ScienceAMSSCAS

ISBN: (纸本)9781538629185

The generalization ability of learning algorithms is the focus of machine learning research,where the empirical risk minimization（ERM） plays an important role when the population distribution of observations is *** of the previous results are mainly based on computational learning theory,which is interested in how many samples are needed to make sure the estimated expected risk satisfies a given accuracy with high *** this paper,we will propose a new algorithm by combining the advantages of both random search and gradient descent algorithms,and show that given an accuracy level of the estimated expected risk,we can generate a hypothesis by our algorithm to guarantee the accuracy with probability 1,and our algorithm will converge in finite *** addition,we will relax the conventional independently and identically distributed（i.i.d.）assumption on the observations to a kind of weakly dependent *** will also provide some simulations to demonstrate our algorithm’s advantages over either random search or gradient descent algorithms.

关键词： ERM random search convergent gradient descent machine learning

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中国临床药理学与治疗学 2024年第6期29卷 601-611页

作者：李雯蒋虎刚王新强李应东刘凯赵信科甘肃中医药大学中西医结合学院甘肃兰州730000 甘肃中医药大学附属医院心血管中心甘肃兰州730000 甘肃省中医药防治慢性疾病重点实验室甘肃兰州730000

目的:通过网络药理学联合实验验证探讨当归黄芪超滤物(RAS-AM)治疗放射性心肌纤维化(RIMF)可能的作用靶点和机制。方法:使用TC-MSP数据库、TCM@TAIWAN台湾中医药资料库和TCMID中医药数据库筛选RAS-AM的成分和靶点,并使用Swiss Target Pr... 详细信息

目的:通过网络药理学联合实验验证探讨当归黄芪超滤物(RAS-AM)治疗放射性心肌纤维化(RIMF)可能的作用靶点和机制。方法:使用TC-MSP数据库、TCM@TAIWAN台湾中医药资料库和TCMID中医药数据库筛选RAS-AM的成分和靶点,并使用Swiss Target Prediction数据库进行靶点预测。从GeneCards和OMIM数据库获得RIMF疾病靶点,疾病和药物的交集靶点通过韦恩在线工具获得,交集靶点通过STRING数据库获得蛋白互作关系(PPI),使用Cytoscape3.9.1软件构建“药物-成分-靶点-疾病”的可视化网络拓扑关系图。通过David数据库对核心靶点进行GO和KEGG富集分析,利用微生信平台作图。实验验证:将60只Wi-star大鼠随机分为空白组、模型组、阳性药物组(1.0mg/kg)、RAS-AM低剂量组(150mg/kg)、RAS-AM中剂量组(300 mg/kg)、RAS-AM高剂量组(600 mg/kg),采用38Gy剂量辐射诱导建立RIMF模型,灌胃给药4周,同时观察大鼠一般情况。大鼠取血和心脏后,HE染色观察心肌组织形态学改变,ELISA法和Western blot法检测网络药理学预测的关键靶点。结果:网络药理学分析得到RAS-AM活性成分34个,靶点705个,共有靶点154个,以IL-6、VEGFA、MMP-2、MMP-9、ACE为前五的核心靶点;GO富集分析共筛选出153个条目,KEGG富集有25条通路。实验部分:HE染色结果显示各用药组心肌细胞变性、坏死好转,心肌间质中炎症细胞浸润减轻,心肌间质纤维结缔组织增生减少。ELISA与Westernblot结果显示,与空白组比较,模型组IL-6、VEGFA、MMP-9表达均升高(P<0.05,P<0.01);与模型组比较,各用药组IL-6、VEGFA、MMP-9表达均不同程度降低(P<0.05),呈剂量依赖性。结论:RAS-AM;可能通过下调IL-6、VEGFA蛋白、MMP-9蛋白等为代表的核心靶点和调控炎症通路、胶原分解等过程,多途径协同以抗RIMF。

关键词：当归黄芪超滤物放射性心肌纤维化网络药理学 IL-6 VEGFA MMP-9

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Nitrogen Isotopes from the Neoproterozoic Liulaobei Formation,North China:Implications for Nitrogen Cycling and Eukaryotic Evolution

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Journal of Earth Science 2022年第5期33卷 1309-1319页

作者： Ting Yang xinqiang wang Dongtao Xu Xiaoying Shi Yongbo Peng School of Earth Science and Resources China University of GeosciencesBeijing100083China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing100083China International Center for Isotope Effect Research Nanjing UniversityNanjing210023China School of Earth Sciences and Engineering Nanjing UniversityNanjing210023China

The nitrogen isotope compositions(δ^(15)N )of sedimentary rocks can provide information about the nutrient N cycling and redox conditions that may have played important roles in biological evolution in Earth’s *** considerableδ^(15)N data for the Precambrian have been published,there is a large gap during the Early Neoproterozoic that restrains our understanding of the linkages among N cycling,ocean redox changes and biological evolution during this key ***,we report bulkδ^(15)N and organic carbon isotope(^(δ)13C_(org))compositions as well as the total nitrogen(TN)and total organic carbon(TOC)contents from the Tonian fossiliferous Liulaobei Formation in the southern part of the North China ***δ^(15)N in the study section is dominated by very stable values centering around+4.3‰,which is moderately lower than that in modern sediments(~+6‰).These positiveδ^(15)N values were attributed to partial denitrification under low primary productivity(scenario 1)and/or denitrification coupled with dissimilatory nitrate reduction to ammonium(DNRA)(scenario 2).In either case,the availability of fixed nitrogen may have provided the nutrient N required to facilitate facilitated eukaryotic *** study highlights the pivotal role of nutrient N in the evolution of eukaryotes.

关键词： Neoproterozoic Tonian Liulaobei Formation nitrogen isotopes eukaryotic evolution nutrient limitation geochemistry