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An Approach for Quantifying the Influence of Seepage Dissolution on Seismic Performance of Concrete Dams

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Computer Modeling in Engineering & Sciences 2022年第4期131卷 97-117页

作者： Shaowei Wang cong Xu Hao Gu Pinghua Zhu Hui Liu bo Xu School of Environmental and Safety Engineering Changzhou UniversityChangzhou213164China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing210029China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing210098China College of Hydraulic Science and Engineering Yangzhou UniversityYangzhou225009China

Many concrete dams seriously suffer from long-term seepage dissolution,and the induced mechanical property deterioration of concrete may significantly affect the structural performance,especially the seismic *** approach is presented in this paper to quantify the influence of seepage dissolution on seismic performance of concrete *** connect laboratory test with numerical simulation,dissolution tests are conducted for concrete specimens and using the cumulative relative leached calcium as an aging index,a deterioration model is established to predict the mechanical property of leached concrete in the first step.A coupled seepage-calcium dissolutionmigrationmodel containing two calculation modes is proposed to simulate the spatially non-uniformdeterioration of concrete *** on the simulated state of a roller compacted concrete dam subjected to 100 years of seepage dissolution,seismic responses of the damare subsequently *** which the nonlinear cracking of concrete,the radiation damping of the far-field foundation is *** results show that seepage dissolution will seriously weaken the seismic safety of concrete dams because of the dissolution-induced decrease of effective thickness of the dam *** upstream surface,dam toe and gallery wall suffer from a large degree of dissolution,whereas it is minimal and basically the same inside the dam body,at a degree of 0.19%within 100 *** horizontal displacements of dam crest under the design static load and fortification against earthquake increase by 6.9%and 21.9%,respectively,and the dissolution-induced seismic cracking leads to the failure of dam anti-seepage *** study can provide engineers with a reference basis for reinforcement decision of old concrete dams.

关键词： Concrete dams seepage dissolution deterioration prediction model seismic performance failure mode

Solid Phase Synthetic Reaction of Sodium Pyroxene for Na_2CO_3-Fe(OH)_3-H_2SiO_3 System

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Journal of Iron and Steel Research International 2013年第1期20卷 21-25页

作者： WANG Yi-ci ZHANG Jian-liang WANG yue-cong LUO Guo-ping College of Metallurgical and Ecological Engineering University of Science and Technology Beijing College of Material and Metallurgy University of Science and Technology Inner Mongolia

In order to explore synthetic method of pure sodium pyroxene,the pure chemical reagents of Na2CO3,Fe（OH）3 and H2SiO3were used as raw materials,and the possible solid phase reactions for Na2CO3-Fe（OH）3-H2SiO3system in heating process had been studied by means of differential thermal analysis（DTA）and X-ray diffraction（XRD）. The influencing factors of sodium pyroxene（NaFeSi2O6）synthetic reaction,such as sintering temperature and holding time,had also been *** results show that sodium pyroxene can be largely synthesized at 737℃;it is helpful for synthesis of sodium pyroxene to increase sintering temperature appropriately,and the best temperature should be controlled at 900℃or so,because it will melt and decompose at temperatures higher than 900℃.In those influencing factors of sodium pyroxene synthesis the most important is *** results will be helpful for providing pure NaFeSi2O6for further research on the formation of SFCA for NaFeSi2O6-KAlSi2O3-CaO-Fe2O3-CaF2 system in the sintering process of Bayan-obo iron ore.

关键词： solid phase synthesis sodium pyroxene Naz CO3-Fe(OH)3-H2 SiO3 system

Negative Bias Temperature Instability ＂Recovery＂ under Negative Stress Voltage with Different Oxide Thicknesses

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Chinese Physics Letters 2011年第1期28卷 175-178页

作者： CAO Yan-Rong MA Xiao-Hua HAO yue ZHU Min-bo TIAN Wen-Chao ZHANG yue School of Electronical and Machanical Engineering Xidian University Xi'an 710071 School of Technical Physics Xidian University Xi 'an 710071 Key Lab of Wide Band-Gap Semiconductor Materials and Devices Xi'an 710071

Different phenomena are observed under negative gate voltage stress which is smaller than the previous degra- dation stress in PMOSFETs with different oxide thicknesses. We adopt the real time method to make a point of the drain current to study the degradation and recovery of negative bias temperature instability （NBTI）. For the device with thin oxide, recovery phenomenon appears when smaller negative voltage stress was applied, due to the more influencing oxide charges detrapping effects than the interface states. For the device with thick oxide, not recovery but degradation phenomenon comes forth. As many charges are trapped in the deeper position and higher energy level in the oxide, these charges can not be detrapped. Therefore, the effect of the charge detrapping is smaller than that of the interface states in the thick oxide. The degradation presents itself during the ＇recovery＇ time.

关键词： Electronics and devices Semiconductors

Wind pressure acting on greenhouses: A review

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International Journal of Agricultural and Biological Engineering 2021年第2期14卷 1-8页

作者： cong Wang bo Nan Tieliang Wang Yikui Bai Yuqing Li College of Water Conservancy Shenyang Agricultural UniversityShenyang 110866China

Greenhouses are widely used in agricultural and horticultural *** the characteristics of lightweight,small stiffness and high flexibility,greenhouses are sensitive to wind *** the calculation of wind loads,the wind pressure coefficient(Cp)is *** rationality of the value directly affects the safety and economy of ***,the Cp values estimation is one of the most important issues in the design of *** order to make full use of the existing research results,in this study,three main methods for estimating Cp values were analyzed,namely,full-scale field experiment,wind tunnel experiment and numerical *** factors influencing the Cp values were then reviewed including greenhouse design parameters,greenhouse group,overhanging eaves,ventilation and wind *** on the existing researches,suggestions for future development and research work were also put *** to the flexibility and deformability of greenhouses,the fluid-solid coupling method should be used to analyze the effects of vibrations on wind *** interaction of building parameters(such as the number of spans,ridge height,roof shape and slope angle)and terrain around the greenhouse should be taken into consideration *** destructive vortices occurred on the greenhouse should be further investigated.

关键词： computational fluid dynamics greenhouse wind pressure coefficients wind tunnel influence factors

Discrepancies in boreal summer monsoon rainfall between GPCP and CMAP products during 1979–2014

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Atmospheric and Oceanic Science Letters 2016年第3期9卷 226-233页

作者： HAO Yu-Qian ZHU cong-Wen LIU bo-Qi Institute of Climate System Chinese Academy of Meteorological Sciences State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences

This study compares the boreal summer monsoon （BSM） precipitation between the GPCP and CMAP products during 1979-2014. The authors apply temporal, spatial correlation and error evaluation methods to evaluate their discrepancies in terms of BSM distribution and summer rainfall interannual variability over the five BSM regions. The results suggest that the climatology of the seasonal evolution of BSM rainfall is reflected well in both datasets, and the summer rainfall anomalies of the two products are highly correlated. However, major diversity is found in the rainfall pattern and the magnitude in climatology over the oceanic monsoon areas, especially the western North Pacific monsoon region, as well as in the interannual variability of summer rainfall anomalies over the North Africa and India monsoon regions. Although inconsistency between the two datasets is evident before the 1990s, the use of their arithmetic mean is demonstrated to be an efficient way to reduce the uncertainty between them.

关键词： GPCP CMAP boreal summermonsoonl interannualvariability data evaluation

DBU-based CO2 absorption-mineralization system: Reaction process,feasibility and process intensification

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Chinese Journal of Chemical Engineering 2020年第4期28卷 1145-1155页

作者： cong Luo Kejing Wu Hairong yue Yingying Liu Yingming Zhu Wei Jiang Houfang Lu Bin Liang School of Chemical Engineering Sichuan UniversityChengdu 610065China Institute of New Energy and Low-carbon Technology Sichuan UniversityChengdu 610207China

Amine-based carbon dioxide(CO2)capture is still limited by high desorption energy *** CO2 into carbonate is a safer and more permanent *** this work,calcium oxide(CaO)is introduced to perform chemical desorption instead of thermal desorption on 1,8-diazabicyclo[5.4.0]undec-7-ene(DBU)aqueous solution after CO2 *** X-ray diffraction(XRD)patterns of solid products show the formation of calcite calcium carbonate(CaCO3),which prove the feasibility of this *** effects of reaction temperature,reaction time and Ca2+/CO32-molar ratios on the related reactions in CO2 absorption-mineralization process and CaCO3 precipitation are discussed,and purer CaCO3 is obtained by ultrasonic *** CaCO3 content can be increased to 95.8%and the CO2 desorption ratio can achieve 80%by 30 min ultrasonic dispersion treatment under the conditions(40℃,180 min,Ca2+/CO32-molar ratio=1.0).After five cycles,DBU aqueous solution shows stable CO2 absorption and mineralization *** transform infrared spectroscopy(FT-IR)spectra of the reaction process also indicate the regeneration of the *** with thermal desorption,this process is exothermic,almost without no additional heat.

关键词： CO2 mineralization CaCO3 1,8-Diazabicyclo[5.4.0]undec-7-ene aqueous Reaction process

Recent Developments of Dinitrogen Activation on Metal Complexes and Clusters

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Chinese Journal of Structural Chemistry 2022年第12期41卷 80-88页

作者： Xue-Lu Ma Meng Li Jun-bo Lu cong-Qiao Xu Jun Li School of Chemical&Environmental Engineering China University of Mining&TechnologyBeijing 100083China Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China Department of Chemistry and Key Laboratory of Organic Optoelectronics&Molecular Engineering of Ministry of Education Tsinghua UniversityBeijing 100084China

Dinitrogen(N_(2)) is the major component of the atmosphere and many factors bring about dinitrogen inertness with low reactivity. Dinitrogen activation on metal complexes and clusters under ambient condition is the long-standing goal in the modern chemistry. In this review,an attempt has been made to survey the mechanistic aspects of dinitrogen activation and functionalization based on different coordination binding modes of dinitrogen. Our goal is to provide a comprehensive survey of dinitrogen activation in order to guide the relevant research in the future.

关键词： dinitrogen activation binding mode dinitrogen complex metal cluster synergistic mechanism

Molecular cloning,characterization and promoter analysis of LbgCWIN1 and its expression profiles in response to exogenous sucrose during in vitro bulblet initiation in lily

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Horticultural Plant Journal 2024年第2期10卷 545-555页

作者： cong Gao Shiqi Li Yunchen Xu yue Liu Yiping Xia Ziming Ren Yun Wu Genomics and Genetic Engineering Laboratory of Ornamental Plants Institute of Landscape ArchitectureCollege of Agriculture and BiotechnologyZhejiang UniversityHangzhouZhejiang 310058China Laboratory of Flower Bulbs Department of Landscape ArchitectureSchool of Civil Engineering and ArchitectureZhejiang Sci-Tech UniversityHangzhouZhejiang 310018China

Lily(Lilium spp.) is an important ornamental flower, which is mainly propagated by bulbs. Cell wall invertases(CWINs), which catalyze the irreversibly conversion of sucrose into glucose and fructose in the extracellular space, are key enzymes participating in sucrose allocation in higher plants. Previous studies have shown that CWINs play an essential role in bulblet initiation process in bulbous crops, but the underlying molecular mechanism remains unclear. Here, a CWIN gene of Lilium brownii var. giganteum(Lbg) was identified and amplified from genomic DNA. Quantitative RT-PCR assays revealed that the expression level of LbgCWIN1 was highly upregulated exactly when the endogenous starch degraded in non-sucrose medium during in vitro bulblet initiation in Lbg. Phylogenetic relationship, motif, and domain analysis of LbgCWIN1 protein and CWINs in other plant species showed that all sequences of these CWIN proteins were highly conserved. The promoter sequence of LbgCWIN1 possessed a number of alpha-amylase-, phytohormone-, light-and stress-responsive cis-elements. Meanwhile, β-glucuronidase(GUS) assay showed that the 459 bp upstream fragment from the translational start site displayed maximal promoter activity. These results revealed that LbgCWIN1 might function in the process of in vitro bulblet initiation and be in the response to degradation of endogenous starch.

关键词： Lilium brownii var.giganteum LbgCWIN1 Phylogenetic analysis Promoter analysis Bulblet initiation

Enhancing thermoelectric performance in P-type Mg_(3)Sb_(2)-based Zintls through optimization of band gap structure and nanostructuring

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Journal of Materials Science & Technology 2024年第3期170卷 25-32页

作者： Yi-bo Zhang Ji-Sheng Liang Chengyan Liu Qi Zhou Zhe Xu Hong-bo Chen Fu-cong Li Ying Peng Lei Miao Guangxi Key Laboratory of Information Material Engineering Research Center of Electronic Information Materials and DevicesMinistry of EducationSchool of Material Science and EngineeringGuilin University of Electronic TechnologyGuilin 541004China Guangxi Key Laboratory for Relativity Astrophysics Center on Nanoenergy ResearchGuangxi Key Laboratory of Processing for Nonferrous Metal and Featured MaterialsSchool of Physical Science&TechnologyGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Precision Navigation Technology and Application Guilin University of Electronic TechnologySchool of Information and CommunicationGuilin 541004China

P-type Mg_(3)Sb_(2)-based Zintls have attracted considerable interest in the thermoelectric(TE)field due to their environmental friendliness and low ***,compared to their n-type counterparts,they show relatively low TE performance,limiting their application in TE *** this work,we simultaneously introduce Bi alloying at Sb sites and Ag doping at Mg sites into the Mg_(3)Sb_(2)to coopera-tively optimize the electrical and thermal properties for the first time,acquiring the highest ZT value of∼0.85 at 723 K and a high average ZT of 0.39 in the temperature range of 323-723 K in sample Mg_(2.94)Ag_(0.06)Sb_(1.9)Bi_(0.1).The first-principle calculations show that the codoping of Ag and Bi can shift the Fermi level into the valence band and narrow the band gap,resulting in the increased carrier concentration from 3.50×10^(17)cm^(-3)in the reference Mg 3 Sb 0.9 Bi 0.1 to∼7.88×10^(19)cm^(-3)in sample Mg 2.94 Ag 0.06 Sb 0.9 Bi *** a result,a remarkable power factor of∼778.9μW m^(-1)K^(-2)at 723 K is achieved in sample Mg 2.94 Ag 0.06 Sb 0.9 Bi ***,a low lattice thermal conductivity of∼0.48 W m^(-1)K^(-1)at 723 K is also obtained with the help of phonon scattering at the distorted lattice,point defects,and nano-precipitates in sample Mg 2.94 Ag 0.06 Sb 0.9 Bi *** synergistic effect of using the multi-element co-doping/-alloying to optimize electrical properties in Mg_(3)Sb_(2)holds promise for further improving the TE performance of Zintl phase materials or even others.

关键词： Thermoelectric materials Band engineering Nanostructuring P-type Mg_(3)Sb_(2) Ag and Bi Co-doping