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吉林工程技术师范学院学报 2017年第4期33卷 72-73,76页

作者：杨建华钟毅王显峰吉林工程技术师范学院机械工程学院吉林长春130052

采用双金属浇注方法防止灰铸铁铸件在铸造中产生的铸造裂纹、白口组织、缩孔、缩松等铸造缺陷,该工艺方法不仅能提高铸件的机械性能,还能降低铸造成本。

关键词：双金属浇注机床铸件浇注工艺

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68卷 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.

关键词： stomach neoplasms precancerous conditions cancer screening cumulative incidence risk stratification

Variable Selection for the Partial Linear Single-Index Model

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Acta Mathematicae Applicatae Sinica 2017年第2期33卷 373-388页

作者： Wu wang zhong-yi ZHU Department of Statistics School of Management Fudan University Shanghai 200433 China

In this paper, we consider the issue of variable selection in partial linear single-index models under the assumption that the vector of regression coefficients is sparse. We apply penalized spline to estimate the nonparametric function and SCAD penalty to achieve sparse estimates of regression parameters in both the linear and single-index parts of the model. Under some mild conditions, it is shown that the penalized estimators have oracle property, in the sense that it is asymptotically normal with the same mean and covariance that they would have if zero coefficients are known in advance. Our model owns a least square representation, therefore standard least square programming algorithms can be implemented without extra programming efforts. In the meantime, parametric estimation, variable selection and nonparametric estimation can be realized in one step, which incredibly increases computational stability. The finite sample performance of the penalized estimators is evaluated through Monte Carlo studies and illustrated with a real data set.

关键词： nonparametric link function SCAD penalty semiparametric model spline estimation variable selection

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流域治理与水文要素变化浅析

吉林水利 2002年第4期 14-15页

作者：刘忠义王琮璞姜嘉礼辽宁省水文水资源勘测局锦州分局辽宁锦州121000

以水文要素的变化为依据，分析流域治理效果，从水文要素的变化可以证明水保工作是一项治标又治本的举措，意义非常深远。

关键词：水文要素水土保特流域治理水土流失

Capacity and failure mechanism of laterally loaded jet-grouting reinforced piles: Field and numerical investigation

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Science China(Technological Sciences) 2016年第5期59卷 763-776页

作者： HE Ben wang Li zhong HONG yi College of Civil Engineering and Architecture Zhejiang University

This study presents the results of field and numerical investigations of lateral stiffness, capacity, and failure mechanisms for plain piles and reinforced concrete piles in soft clay. A plastic-damage model is used to simulate concrete piles and jet-grouting in the numerical analyses. The field study and numerical investigations show that by applying jet-grouting sur- rounding the upper 7.5D （D = pile diameter） of a pile, lateral stiffness and beating capacity of the pile are increased by about 110% and 100%, respectively. This is partially because the jet-grouting increases the apparent diameter of the pile, so as to en- large the extent of failure wedge and hence passive resistance in front of the reinforced pile. Moreover, the jet-grouting pro- vides a circumferential confinement to the concrete pile, which suppresses development of tensile stress in the pile. Corre- spondingly, tension-induced plastic damage in the concrete pile is reduced, causing less degradation of stiffness and strength of the pile than that of a plain pile. Effectiveness of the circumferential confinement provided by the jet-grouting, however, diminishes once the grouting cracks because of the significant vertical and circumferential tensile stress near its mid-depth. The lateral capacity of the jet-grouting reinforced pile is, therefore, governed by mobilized passive resistance of soil and plastic damage of jet-grouting.

关键词： jet-grouting reinforced cast-in-place piles field test finite element analysis lateral bearing capacity lateral stiffness plastic damage failure mechanism

Finite element analysis of stiffness and static dent resistance of aluminum alloy double-curved panel in viscous pressure forming

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Transactions of Nonferrous Metals Society of China 2009年第S2期19卷 312-317页

作者： LI yi wang zhong-Jin School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

The static dent resistance performance of the aluminum alloy double-curved panel formed using viscous pressure forming (VPF)was studied by finite element analysis,which mainly considers the forming process *** whole simulation consisting of three stages,i.e.,forming,spring-back and static dent resistance,was carried out continuously using the finite element code *** influence of blank holder pressure(BHP)and the drawbead on the stiffness and the static dent resistance of the panels formed using VPF was *** results show that the adequate setting of the drawbead can increase the plastic deformation of the double-curved panel,which is beneficial to the initial stiffness and the static dent *** is an optimum BHP range for the stiffness and the static dent resistance.

关键词： aluminum alloy double-curved panel viscous pressure forming panel stiffness static dent resistance finite element analysis

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电容式薄膜真空压力传感器设计

传感器与微系统 2017年第3期36卷 84-86,90页

作者：王凡崔宏敏宗义仲王文博中国电子科技集团公司第四十九研究所黑龙江哈尔滨150001

为了满足在工程型号上的使用要求,解决真空压力传感器敏感探头壳体与传感器壳体隔离绝缘问题;传感器输出信号非线性的补偿问题;传感器热零点漂移的全电路的温度补偿问题,采用电容式薄膜封装结构,壳体为电容的另一极,在0.1~100 Pa的范围... 详细信息

为了满足在工程型号上的使用要求,解决真空压力传感器敏感探头壳体与传感器壳体隔离绝缘问题;传感器输出信号非线性的补偿问题;传感器热零点漂移的全电路的温度补偿问题,采用电容式薄膜封装结构,壳体为电容的另一极,在0.1~100 Pa的范围内进行了校准测试,实现了传感器0.2%FS的测量精度。

关键词：电容式薄膜真空压力传感器零点漂移温度补偿

Closed-form solution of beam on Pasternak foundation under inclined dynamic load

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Acta Mechanica Solida Sinica 2017年第6期30卷 596-607页

作者： Yu Miao Yang Shi Guobo wang yi zhong School of Civil Engineering and Mechanics Huazhong University of Science and Technology Wuhan 430074 China Hubei Key Laboratory of Roadway Bridge & Structure Engineering Wuhan University of Technology Wuhan Hubei 430070 China

The dynamic response of an infinite Euler–Bernoulli beam resting on Pasternak foundation under inclined harmonic line loads is developed in this study in a closed-form *** conventional Pasternak foundation is modeled by two parameters wherein the second parameter can account for the actual shearing effect of soils in the vertical ***,it is more realistic than the Winkler model,which only represents compressive soil ***,the Pasternak model does not consider the tangential interaction between the bottom of the beam and the foundation;hence,the beam under inclined loads cannot be considered in the *** this study,a series of horizontal springs is diverted to the face between the bottom of the beam and the foundation to address the limitation of the Pasternak model,which tends to disregard the tangential interaction between the beam and the *** horizontal spring reaction is assumed to be proportional to the relative tangential *** governing equation can be deduced by theory of elasticity and Newton’s laws,combined with the linearly elastic constitutive relation and the geometric equation of the beam body under small deformation *** Fourier transformation is used to simplify the geometric equation into an algebraic equation,thereby conveniently obtaining the analytical solution in the frequency domain for the dynamic response of the *** Fourier inverse transform and residue theorem are also adopted to derive the closed-form *** proposed solution is verified by comparing the degraded solution with the known results and comparing the analytical results with numerical results using *** computations of distinct cases are provided to investigate the effects of the angle of incidence and shear stiffness on the dynamic response of the *** are realistic and can be used as reference for future engineering designs.

关键词： Beam Harmonic line load Pasternak foundation Tangential interaction between the beam and the foundation Fourier transform

Synthesis of Poly(p-phenyleneethynylene)s with Crosslinkable End or Side Groups and Its Solid State Structure and Optical Properties Before and after Crosslinking

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Chemical Research in Chinese Universities 2009年第5期25卷 767-772页

作者： wang Wen-zhong LIU zhong-yi HUANG Peng-cheng Department of Polymer Materials and Composites School of Materials Science and Engineering Beihang University Beijing 100083 P. R. China

Two crosslinkable poly（p-phenyleneethynylene）s（PPEs）： poly[2,5-di（2＇-ethyl-hexyloxy）-1,4-phenylenecthynylene] with end-capped vinyl（PPE1） and poly[2,5-di（allyloxy）-1,4-phenyleneethynylene-2,5-di（2＇-ethyl-hexyloxy）-1,4-phenyleneethynylene]（PPE2） were synthesized. Via the thermal addition reactions of vinyl end groups of PPE1 and allyloxy side groups of PPE2, crosslinked polymers C-PPE1 and C-PPE2 were obtained, respectively. The two polymers were characterized by wide-angle X-ray diffraction（WXRD）, ultraviolet-visible（UV-Vis） absorption, and photoluminescence（PL）. The results indicate that in the solid state, the polymer chains of PPE1 were packed with a low degree of crystallinity because of the sterically hindered（2＇-ethyl-hexyl）oxy branched side chains, but, because of the introduction of allyloxy side chains, the polymer chains of PPE2 were packed in an order fashion with a high degree of crystallinity. Because of the high crosslinking density in C-PPE2, the formation of aggregates and excimer was hampered by the formed crosslinking network more effectively in C-PPE2 film than in C-PPE1 film.

关键词： Poly(p-phenyleneethynylene) Crosslinkable polymer Optical property Packing fashion

Recent advances and key perspectives of in-situ studies for oxygen evolution reaction in water electrolysis

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Green Energy & Environment 2024年第10期9卷 1497-1517页

作者： yi wang Zichen Xu Xianhong Wu zhong-Shuai Wu State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China University of Chinese Academy of Sciences Shijingshan DistrictBeijing100049China Dalian National Laboratory for Clean Energy Chinese Academy of SciencesDalian116023China

Electricity-driven water splitting to produce hydrogen is one of the most efficient ways to alleviate energy crisis and environmental pollution problems,in which the anodic oxygen evolution reaction(OER)is the key half-reaction of performance-limiting in water *** the complicated reaction process and surface reconstruction of the involved catalysts under actual working conditions,unraveling the real active sites,probing multiple reaction intermediates and clarifying catalytic pathways through in-situ characterization techniques and theoretical calculations are *** this review,we summarize the recent advancements in understanding the catalytic process,unlocking the water oxidation active phase and elucidating catalytic mechanism of water oxidation by various in-situ characterization ***,we introduce conventionally proposed traditional catalytic mechanisms and novel evolutionary mechanisms of OER,and highlight the significance of optimal catalytic pathways and intrinsic ***,we provide a comprehensive overview of the fundamental working principles,different detection modes,applicable scenarios,and limitations associated with the in-situ characterization ***,we exemplified the in-situ studies and discussed phase transition detection,visualization of speciation evolution,electronic structure tracking,observation of reaction active intermediates,and monitoring of catalytic products,as well as establishing catalytic structure-activity relationships and catalytic ***,the key challenges and future perspectives for demystifying the water oxidation process are briefly proposed.

关键词： In-situ studies Water splitting Oxygen evolution reaction Catalytic mechanism