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高混凝土坝位移监控模型前期温度因子的优化

水电能源科学 2025年第1期43卷 127-131页

作者：柴斌高邹嘉鑫郑徐敏王少伟常州大学城市建设学院江苏常州213164

当前高混凝土坝位移监控模型未考虑温度敏感性,所有位移测点均采用相同的温度建模因子,且坝体温度和位移同属响应量,以温度为因子所建位移模型缺乏预测能力。对此,利用Shapley法确定各位移测点较敏感的温度测点,再结合基于滞后影响机理... 详细信息

当前高混凝土坝位移监控模型未考虑温度敏感性,所有位移测点均采用相同的温度建模因子,且坝体温度和位移同属响应量,以温度为因子所建位移模型缺乏预测能力。对此,利用Shapley法确定各位移测点较敏感的温度测点,再结合基于滞后影响机理的高混凝土坝实测温度场分区及其因果预测模型,提出了以坝址气温和上游库水位为基础的前期温度因子构建方法,建立了考虑温度滞后性和敏感性的高混凝土坝位移因果预测模型。对锦屏一级拱坝的实例分析结果表明,该方法操作简便、可行性高,为前期气温和库水位选用总时段长度和分段间隔提供了定量依据。相较于谐波温度因子和传统前期分段平均温度因子,所建位移模型预测精度高、测点适应性好,预测均方根误差分别平均降低了24.9%、29.2%。

关键词：高混凝土坝位移监控模型滞后影响机理温度敏感性前期温度因子

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低速水流作用下水泥净浆缝面溶蚀的试验研究

水电能源科学 2025年第1期43卷 79-83页

作者：高文龙王少伟吴佳雯夏群胡坤常州大学环境科学与工程学院江苏常州213164 常州大学城市建设学院江苏常州213164

为探究低速水流作用下水泥净浆缝面流速与加速钙溶蚀效应之间的定量关系,使用1 moL/L NH_4Cl溶液作为溶蚀介质,在0.0、0.3、0.6、1.2、2.4 m/s流速下对水泥净浆单裂缝表面开展静态和动态溶蚀试验,研究缝面溶蚀—冲蚀深度、钙离子溶出量... 详细信息

为探究低速水流作用下水泥净浆缝面流速与加速钙溶蚀效应之间的定量关系,使用1 moL/L NH_4Cl溶液作为溶蚀介质,在0.0、0.3、0.6、1.2、2.4 m/s流速下对水泥净浆单裂缝表面开展静态和动态溶蚀试验,研究缝面溶蚀—冲蚀深度、钙离子溶出量、质量损失率、曲折度、粗糙度和剩余固相钙含量6种评价指标的时变规律,并通过SEM/EDS和XRD进行微观机理解释。结果表明,2.4 m/s范围内的净浆缝面动态溶蚀过程仍满足Fick扩散定律,流动水对缝面无明显冲蚀作用,加速溶蚀效应与流速之间呈负指数函数型增长关系;流动水仅在溶蚀初期会引起缝面曲折度和粗糙度的显著降低,后期几乎无影响;流动水仅加速缝面溶蚀过程,不同流速下的最终缝面剩余固相钙含量相近。

关键词：水泥净浆低速水流单裂缝缝面加速溶蚀效应

含砂率和粒径对砂浆缝面溶蚀-冲蚀性能的影响

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水电能源科学 2025年第2期43卷 113-117页

作者：吴佳雯王少伟高文龙夏群胡坤常州大学环境科学与工程学院江苏常州213164 常州大学城市建设学院江苏常州213164

在1.2 m/s流速下对水泥砂浆缝面开展动态加速溶蚀试验,分析缝面溶蚀评价指标的时变规律,研究含砂率和细度模数对砂浆缝面溶蚀-冲蚀性能的影响。结果表明,缝面溶蚀-冲蚀深度和钙溶出量随含砂率和细度模数的增大分别呈先增加、后降低和逐... 详细信息

在1.2 m/s流速下对水泥砂浆缝面开展动态加速溶蚀试验,分析缝面溶蚀评价指标的时变规律,研究含砂率和细度模数对砂浆缝面溶蚀-冲蚀性能的影响。结果表明,缝面溶蚀-冲蚀深度和钙溶出量随含砂率和细度模数的增大分别呈先增加、后降低和逐渐降低的趋势,最佳含砂率为30%;质量损失率随含砂率的增加呈逐渐减小的趋势,溶蚀90 d前,砂细度模数对质量损失率的影响较小,但溶蚀150 d后,粗砂、中砂、细砂缝面试件的质量损失率依次减小,分别为8.98%、7.60%、6.62%;粗糙度和曲折度随溶蚀时间的延长呈先快速、后缓慢的下降趋势,含砂率较高试件的缝面较为粗糙,导致溶蚀后砂粒剥落质量较大、形貌变化明显;低速水流对砂浆缝面的损伤机制以加速钙溶蚀为主。

关键词：水泥砂浆缝面含砂率细度模数低速水流溶蚀-冲蚀效应

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No-go guide for the Hubble tension:Late-time or local-scale new physics

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 73-85页

作者： Lu Huang shao-Jiang wang wang-wei Yu CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of Sciences(CAS)Beijing100190China Asia Pacific Center for Theoretical Physics(APCTP) Pohang37673Korea Max-Planck-Institut für Gravitationsphysik(Albert-Einstein-Institut) HannoverD-30167Germany Leibniz Universität Hannover Hannover30167Germany

The standard model of modern cosmology might be cracked by the recent persistent hot debate on the Hubble-constant(H_(0))tension,which manifests itself as the sound-horizon(r_(s))tension or absolute-magnitude(M_(B))tension if deeming the origin of the Hubble tension from modifying the early or late Universe,*** this study,we achieve a fully model-independent constraint(fitting a model-independent global parameterization to a model-independent inverse distant ladder with a modelindependent high-redshift calibration)on late-time models with strong evidence against homogeneous new physics over theΛ-cold-dark-matter(ΛCDM)*** using this model-independent constraint to calibrate sufficiently local supernovae with corresponding late-time models extrapolated below the homogeneity scale,we find surprisingly that,although both H_(0)tension and MB tension are absent in our local Universe,a combination of H_(0)and M_(B)as the intercept a B of the magnitude-redshift relation exhibits 3~7σtension even for theΛCDM *** aBtension seems to call for local-scale inhomogeneous new physics disguised as local observational systematics.

关键词： Hubble constant inverse distance ladder local Universe

Crack status analysis for concrete dams based on measured entropy

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Science China(Technological Sciences) 2016年第5期59卷 777-782页

作者： WU Bang Bin WU Zhong Ru CHEN Bo SU Huai Zhi BAO Teng Fei wang shao wei State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University College of Water Conservancy and Hydropower Engineering Hohai University

The integrity and safety of concrete darns are seriously affected by the existing cracks in dam bodies, and some serious cracks may cause dam failure or disaster. The propagation of cracks in concrete dams is accompanied by changes in energy distribution, which can be represented by changes in the structure＇s system entropy. Therefore, the entropy theory can be used in analyzing the behavior of dam cracks. Due to the randomness and locality of crack propagation, it is difficult to predict the loca- tion of cracks by traditional monitoring methods. To solve this problem, the influence of spatial positions of monitoring points on inspection zones is represented by a weight index, and the weight index is determined by the distance measure method proposed in this paper. Through the weighted linear fusion method, the entropy of multiple monitoring points is obtained for analyzing the behavior of dam cracks in the selected zones. Meanwhile, the catastrophe theory is used as the variation criterion of an entropy sequence in order to predict the instability time of dam cracks. Case studies are put forward on a high arch darn, and the fusion entropy is calculated according to the monitoring data from strain gauges. Results show that the proposed method can effectively predict the occurrence time and location of dam cracks regardless of the layout of monitoring instruments, and it is a new way to analyze the occurrence and propagation of dam cracks.

关键词： energy measured data entropy changes multiple monitoring points fusion concrete dam

An efficient synthesis of 3-(guaiazulene-1-yl)succinimides by addition of guaiazulene to maleimides

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Chinese Chemical Letters 2011年第7期22卷 789-792页

作者： Dao Lin wang shao Fei Li wei Li Yuan Feng Li Li Nan Lin Key Laboratory of Synthesis & Application of Functional Compound College of Chemistry & Chemical Engineering Bohai University Jinzhou 121001 China

A facile, efficient synthesis of 3-（guaiazulen-l-yl）succinimides was developed by Michael-type addition of guaiazulene to maleimides in the presence of p-toluenesulfonic acid under mild reaction conditions.

关键词： Guaiazulene Succinimidcs Michael-type addition p-Toluenesulfonic acid

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 67-74页

作者： Song He Li Li Sai wang shao-Jiang wang Center for Theoretical Physics and College of Physics Jilin UniversityChangchun 130012China School of Physical Science and Technology Ningbo UniversityNingbo 315211China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences(UCAS)Hangzhou 310024China Theoretical Physics Division Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Physical Sciences University of Chinese Academy of Sciences(UCAS)Beijing 100049China Max Planck Institute for Gravitational Physics(Albert Einstein Institute) Am Muhlenberg 1Golm 14476Germany

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition,yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT)left *** specific baryon chemical poten-tial,the first-order QCD phase transition agrees with the observational constraint of baryon ***,therefore,provides a scenario for phase transition gravitational waves(GWs)within the standard model of particle *** these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA)observations,the duration of this FoPT can be well constrained,and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Study on multi-wavelength thin film thickness determination method

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红外与毫米波学报 2024年第6期43卷 813-819页

作者： SHI Ce XIE Mao-Bin ZHENG wei-Bo JI Ruo-Nan wang shao-wei LU wei School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China State Key Laboratory of Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China Shanghai Engineering Research Center of Energy-Saving Coatings Shanghai 200083China Shanghai Key Laboratory of Optical Coatings and Spectral Modulation Shanghai 200083China Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai 200083China

This work introduces a novel method for measuring thin film thickness,employing a multi-wavelength method that significantly reduces the need for broad-spectrum *** traditional techniques that require sev⁃eral hundred spectral data points,the multi-wavelength method achieves precise thickness measurements with data from only 10 *** innovation not only simplifies the process of spectral measurement analysis but al⁃so enables accurate real-time thickness measurement on industrial coating production *** method effective⁃ly reconstructs and fits the visible spectrum(400-800 nm)using a minimal amount of data,while maintaining measurement error within 7.1%.This advancement lays the foundation for more practical and efficient thin film thickness determination techniques in various industrial applications.

关键词： film thickness determination transmittance and reflectance spectra fitting spectral reconstruction

Role of Cervical Cerclage and Vaginal Progesterone in the Treatment of Cervical Incompetence with/without Preterm Birth History

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Chinese Medical Journal 2016年第22期129卷 2670-2675页

作者： shao-wei wang Lin-Lin Ma Shuai Huang Lin Liang Jun-Rong Zhang Department of Obstetrics and Gynecology Beijing Hospital National Center of Gerontology Beijing 100730 China

Background：Preterm birth （PTB） is the leading cause of perinatal morbidity and mortality worldwide,and its prevention is an important health-care *** cervical incompetence is a well-known risk factor for PTB and its incidence is about 0.1-2.0%,while there is no ideal optimum treatment recommended *** cervical incompetence causes about 15% of habitual abortion in 16-28 *** study aimed to evaluate the effectiveness and safety of cervical cerclage and vaginal progesterone in the treatment of cervical incompetence with/without PTB ***：We retrospectively observed the pregnancy outcome of 198 patients diagnosed with cervical incompetence from January 2010 to October 2015 in Beijing *** the 198 women involved,women who had at least one PTB before 32 weeks （including abortion in the second trimester attributed to the cervical competence） were assigned to the PTB history cohort,and others were assigned to the non-PTB history *** women underwent cerclage placement （cervical cerclage group） or administrated with vaginal progesterone （vaginal progesterone group） until *** outcomes of interest were the differences in gestational age at delivery,the rate of premature delivery,neonatal outcome,complications,and route of delivery between the two treatment ***：Among the 198 patients with cervical incompetence,116 patients in PTB history cohort and 80 patients in non-PTB history cohort were included in the final *** the PTB history cohort,cervical cerclage group had significantly longer cervical length at 2 weeks after the start of treatment （23.1 ± 4.6 mm vs.12.4 ± 9.1 mm,P =0.002）,higher proportion of delivery ≥37 weeks＇ gestation （63.4% vs.33.3%,P =0.008）,bigger median birth weight （2860 g vs.2250 g,P =0.031）,and lower proportion of neonates whose 1-min Apgar score 〈7 （5.9% vs.33.3%,P =0.005）,compared with vaginal progesterone *** significant differences were found in other outcome measures be

关键词： Cervical Cerclage Cervical Incompetence Preterm Delivery Vaginal Progesterone