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Effects of freezing-thawing on the engineering performance of core wall soil materials of a dam in the process of construction

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Journal of Mountain Science 2020年第11期17卷 2840-2852页

作者： REN Xiu-ling YU Qi-hao zhang Gui-ke YUE Pan LIU En-long zhang Zhen-yu you Yan-hui State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Yalong River Hydropower Development Company LtdChengdu 610065China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resources and HydropowerSichuan UniversityChengdu 610065China

The construction of water conservancy projects in cold regions experiences freezing-thawing cycles,which can greatly change the engineering properties of soil and have a significant impact on the construction of *** Hydropower Station(LHS),is a controlling station with the largest installed capacity among the 7 middle reach projects in the Yalong River,the secondary tributary of the Yangtze *** is located in a seasonally frozen soil *** on the measured data of air and ground temperature in winter in the dam core wall,the freezing-thawing variation of gravelly soil and contact clay during the filling process of the core wall are compared and analyzed,then the main impact factors of the freezing-thawing variation of soils are *** results show that under the influence of air temperature,soil freezes unidirectionally from ground surface downward and deepens gradually,and the thawing processes are different at the aspects of thawing direction and *** temperature and physical properties of soil including soil type,moisture content and dry density affect the freezingthawing processes of *** the impact of engineering construction is more remarkable than natural *** engineering construction affects soil temperature and freezing-thawing process by controlling the initial temperature of soil,the speed and duration of the technological conversion of paving,compaction,and the length of placed duration at *** to the long placed duration of soil with the slow construction method,the initial temperature of soil gradually reduces,the heat transfer process inside soil is *** the internal heat of soil releases,the decreasing rate of ground temperature of soil at different depths is fast and the frozen depth *** due to the short placed duration of soil with the rapid construction process,the initial temperature of soil is high,high internal heat of soil is supplied every day,and the heat transfer process in

关键词： Lianghekou Hydropower Station(LHS) Gravelly soil Contact clay Freezing-thawing variation Impact factors

Enhanced light harvesting ability in hollow Pt/TiO2 nanoreactor for boosting tetracycline photodegradation

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Progress in Natural Science:Materials International 2024年第4期34卷 767-775页

作者： Danyang Li Yongqi Li Dagui Liao Mengqing Cao Lulu zhang Shasha zhang ling Chen Yawen Chen Huan Wang Jian Qi Feifei you College of Textile and Clothing Yancheng Institute of Technology Hebei Key Laboratory of Flexible Functionals Materials School of Materials Science and Engineering Hebei University of Science and Technology State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences School of Chemical Engineering University of Chinese Academy of Sciences

Utilizing solar energy to decompose tetracycline（TC） is a green strategy to treat wastewater. Herein, a heterogeneous hollow structured TiO2decorated Pt nanoparticles were successfully designed and synthesized via hardtemplate approach and photo-deposition process toward TC photodegradation. The Pt nanoparticles loaded on the surface of hollow structured TiO2can increase the visible light absorption due to the local surface plasmon resonance（LSPR） effect. Furthermore, owing to the tough electron oscillation of the LSPR excitation, the plasmonic hot holes on the surface of Pt nanoparticles can capture the electrons of TiO2, effectively facilitating the separation of photo-excited charge carriers because of the formation of Schottky junction constructed between Pt and TiO2. Combined the natural merits of shorten conveying path of charge carriers and physical structural stability for hollow structure, the optimal Pt/TiO2hetero-junction hybrid showed superior photocatalytic activity and durability for TC photodegradation with the degradation efficiency of 93.8 % after 30 min and the rate constant of 0.09196 min-1under 300 W Xe lamp irradiation. This work displays a heterogeneous hybrids catalyst based on eco-friendly metal and semiconductor materials which can be used in the fields including without limitation TC photodegradation.

关键词： Hollow structure Photodegradation Tetracycline Hetero-junction

Contour reconstruction of three-dimensional spiral CT damage image

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Journal of Innovative Optical Health Sciences 2018年第5期11卷 42-50页

作者： Cui ling-ling zhang Hui The First Affiliated Hospital of Jinzhou Medical University Jinzhou 121001 P.R.China

In order to improve the diagnosis and analysis ability of 3D spiral CT and to reconstruct the contour of 3D spiral CT damage image,a contour reconstruction method based on sharpening template enhancement for 3D spiral CT damage image is *** method uses the active contour LasSO model to extract the contour feature of the 3D spiral CT damage image and enhances the information by sharpening the template *** technique and makes the noise separation of the 3D spiral CT damage *** spiral CT image was procesed with ENT,and the statistical shape model of 3D spiral CT damage image was *** algorithm is used to decompose the feature to realize the analysis and reconstruction of the contour feature of the 3D spiral CT damage image,so as to improve the adaptive feature matching ability and the ability to locate the abnormal feature *** simulation results show that in the 3D spiral CT damage image contour reconstruction,the proposed method performs well in the feature matching of the output pixels,shortens the contour reconstruction time by 20/ms,and provides a strong ability to express the image *** normalized reconstruction error of CES is 30%,which improves the recognition ability of 3D spiral CT damage image,and increases the signal-to noise ratio of peak output by 40 dB over other methods.

关键词： Spiral CT three dimensional image contour feature extraction sharpening template en hancement

Study on threshold segmentation of multi-resolution 3D human brain CT image

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Journal of Innovative Optical Health Sciences 2018年第6期11卷 78-86页

作者： ling-ling Cui Hui zhang The First Hospital A±liated to Jinzhou Medical University Jinzhou 121001 P.R.China

In order to effectively improve the pathological diagnosis capability and feature resolution of 3D human brain CT images,a threshold segmentation method of multi-resolution 3D human brain CT image based on edge pixel grayscale feature decomposition is proposed in this *** this method,first,original 3D human brain image information is collected,and CT image filtering is performed to the collected information through the gradient value decomposition method,and edge contour features of the 3D human brain CT image are ***,the threshold segmentation method is adopted to segment the regional pixel feature block of the 3D human brain CT image to segment the image into block vectors with high-resolution feature points,and the 3D human brain CT image is reconstructed with the salient feature point as *** results show that the method proposed in this paper can provide accuracy up to 100%when the signal-to-noise ratio is 0,and with the increase of signal-to-noise ratio,the accuracy provided by this method is stable at 100%.Comparison results show that the threshold segmentation method of multi-resolution 3D human brain CT image based on edge pixel grayscale feature decomposition is signicantly better than traditional methods in pathological feature estimation accuracy,and it effectively improves the rapid pathological diagnosis and positioning recognition abilities to CT images.

关键词： Multi-resolution 3D human brain CT image segmentation feature extraction recognition

Hydroxyapatite/palmitic acid superhydrophobic composite coating on AZ31 magnesium alloy with both corrosion resistance and bacterial inhibition

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Frontiers of Materials Science 2024年第1期18卷 71-83页

作者： Hang zhang Shu Cai Huanlin zhang Lei ling you Zuo Hao Tian Tengfei Meng Guohua Xu Xiaogang Bao Mintao Xue Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education Tianjin UniversityTianjin 300072China Department of Orthopedic Surgery Spine CenterChangzheng HospitalNaval Medical UniversityShanghai 200003China

The coating-modified magnesium(Mg)alloys exhibit controllable corrosion resistance,but the insufficient antibacterial performance limits their clinical applications as degradable *** coatings show excellent performance in terms of both corrosion resistance and inhibition of bacterial adhesion and *** this work,a hydroxyapatite(HA)/palmitic acid(PA)superhydrophobic composite coating was fabricated on the Mg alloy by the hydrothermal technique and immersion *** HA/PA composite coating showed superhydrophobicity with a contact angle of 153°and a sliding angle of 2°.The coated Mg alloy exhibited excellent corrosion resistance in the simulated body fluid,with high polarization resistance(77.10 kΩ·cm^(2))and low corrosion current density((0.491±0.015)μA·cm^(-2)).Meanwhile,the antibacterial efficiency of the composite coating was over 98% against *** and *** in different *** results indicate that the construction of such superhydrophobic composite coating(HA/PA)on the Mg alloy can greatly improve the corrosion resistance of Mg alloy implants within the human body and avoid bacterial infection during the initial stages of implantation.

关键词： superhydrophobic coating hydroxyapatite corrosion resistance antibacterial

Durability and microstructure analysis of the road base material prepared from red mud and flue gas desulfurization fly ash

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International Journal of Minerals,Metallurgy and Materials 2020年第4期27卷 555-568页

作者： Emile Mukiza ling-ling zhang Xiao-ming Liu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China

The present study aimed to investigate the durability and microstructure evolution of road base materials(RBM)prepared from red mud and flue gas desulfurization fly *** durability testing showed that the strength of RBM with the blast furnace slag addition of 1wt%,3wt%and 5wt%reached 3.81,4.87,and 5.84 MPa after 5 freezing–thawing(F–T)cycles and reached 5.21,5.75,and 6.98 MPa after 20 weting–drying(W–D)cycles,*** results also indicated that hydration products were continuously formed even during W–D and F–T exposures,resulting in an increase of the strength and durability of *** observed increase of macropores(>1μm)after F–T and W–D exposures suggested that the mechanism of RBM deterioration is pore enlargement due to cracks that develop inside their ***,the F–T exposure showed a greater negative effect on the durability of RBM compared to the W–D *** leaching tests showed that sodium and heavy metals were solidified below the minimum requirement,which indicates that these wastes are suitable for use as a natural material replacement in road base construction.

关键词： red mud road base material durability microstructure damage mechanism

Synthesis of Novel Quaternary Selenide K_2CdSnSe_4

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Chemical Research in Chinese Universities 2010年第4期26卷 514-516页

作者： zhang Li-dan HAN Chun-ying FENG Xiu-ling WEI Yong-ge GUO Hong-you College of Sciences Beoing University of Chemical Technology Beijing 100029 P. R. China Department of Chemistry Huaihua Institute Huaihua 418008 P. R. China College of Chemistry and Molecular Engineering Peking University Beoing 100871 P. R. China

A novel quaternary metal selenide, K2CdSnSe4, was synthesized via a molten-salt reaction at 550 ℃. The compound has a one-dimensional structure containing a chain of ∞^1[CdSnSe4]^2- anions separated by K^＋ cations. The crystal belongs to the space group I-4^-2m, with the unit cell parameters a=0.80298（11） nm, b=0.80298（11） nm, c=0.69217（14） nm, α=β=γ=90°. A reflectance spectroscopy study reveals the nature of the semiconductor with an energy gap of 1.7 eV for the compound and it has a strong optical absorotion in a range of 2--5 eV.

关键词： Quatemary metal selenide Solid state synthesis Crystal structure

Research progress on refractory composition and deformability of shell molds for TiAl alloy castings

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China Foundry 2018年第1期15卷 1-10页

作者： Chun-ling Bao Shuang-qi zhang Yu-yan Ren you-wei zhang Hua-sheng Xie Jun Zhao Titanium Alloy Division Shenyang Research Institute of Foundry School of Materials Science and Engineering Shenyang University of Technology

At present, most TiAl components are produced by an investment casting process. Environmental and economic pressures have, however, resulted in a need for the industry to improve the current casting quality, reduce manufacturing costs and explore new markets for the process. Currently, the main problems for investment casting of TiAl alloys are cracks, porosities, and surface defects. To solve these problems, many studies have been conducted around the world, and it is found that casting defects can be reduced by improving composition and properties of the shell molds. It is important to make a summary for the related research progress for quality improvement of TiAl castings. So, the development on refractory composition of shell molds for TiAl alloy investment castings was reviewed, and research progress on deformability of shell mold for TiAl alloy castings both at home and abroad in recent years was introduced. The existing methods for deformability characterization and methods for improving the deformability of shell molds were summarized and discussed. The updated advancement in numerical simulation of TiAl alloy investment casting was presented, showing the necessity for considering the deformability of shell mold during simulation. Finally, possible research points for future studies on deformability of shell mold for TiAl alloy investment casting were proposed.

关键词： TiAl based alloys investment casting shell mold deformability

Detection of HPV Types and Neutralizing Antibodies in Women with Genital Warts in Tianjin City,China

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Virologica Sinica 2010年第1期25卷 8-17页

作者： Xue-ling WU Chun-tao zhang Xiao-ke ZHU you-chun WANG Department of Cell Biology National Institute for the Control of Pharmaceutical and Biological Products （NICPBP） Beijing 100050 China Department of Sexually Transmitted Disease Tianjin Center for Disease Control Tianjin 300011 China

The serum samples and corresponding cervical swabs were collected from 50 women with genital warts from Tianjin city, China. The neutralizing antibodies against HPV-16, -18, -58, -45, -6 and -11 in serum samples were tested by using pseudovirus-based neutralization assays and HPV DNAs in cervical swabs were also tested by using a typing kit that can detect 21 types of HPV. The results revealed that 36% （18/50） of sera were positive for type-specific neutralizing antibodies with a titer range of 160-2560, of which 22%（11/50）, 12%（6/50）, 10%（5/50）, 4%（2/50）, 4%（2/50） and 2%（1/50） were against HPVs -6, -16, -18, -58, -45 and -1 l, respectively. Additionally, 60% （30/50） of samples were HPV DNA-positive, in which the most common types detected were HPV-68（18%）, HPV-16（14%）, HPV-58（12%）, HPV-33（8%） and HPV-6, HPV-11, HPV-18 and HPV-52 （6% each）. The concordance between HPV DNA and corresponding neutralizing antibodies was 56% （28/50） with a significant difference （P〈0.05）. The full-length sequences of five HPV types （HPV -42, -52, -53, -58 and -68） were determined and exhibited 98%-100% identities with their reported genomes. The present data may have utility for investigating the natural history of HPV infection and promote the development of HPV vaccines.

关键词： HPV type Genital warts Pseudovirus Neutralizing antibody DNA