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Study of interfacial transition zones between magnesium phosphate cement and Portland cement concrete pavement

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Journal of Traffic and transportation Engineering(English Edition) 2024年第3期11卷 523-537页

作者： Fei Liu Baofeng Pan Changjun Zhou Ge Li Xiaocun Wang Jiaquan Li Faculty of Infrastructure Engineering Dalian University of TechnologyDalian 116024China tongren city transportation bureau Tongren 554300China Beijing Civil Aviation Design and Research Institute of China Design Group Beijing 101318China

The Portland cement concrete pavement(PCCP)often suffers from different environmental distresses and vehicle load failure,resulting in slab corner fractures,potholes,and other *** repair has become one of the effective ways to open traffic *** this study,a novel type of rapid repair material,basalt fiber reinforced polymer modified magnesium phosphate cement(BFPMPC),is used to rapidly repair ***,the mechanical properties and characteristics of the repair interfaces which are named interfacial transition zones(ITZs)formed by BFPMPC and cement concrete are focused on as a decisive factor for the performance of the rapid *** changing trend of the elastic moduli was studied by nanoindentation experiments in the ITZs with the deconvolution analysis that the elastic moduli of certain kinds of substances can be *** experimental results show that the elastic modulus of ITZ-1 with a width of about20μm can be regarded as 0.098 times of the aggregate,and 0.51 times of the ordinary Portland cement(OPC)*** BFPMPC-OPC mortar ITZ has roughly the same mechanical properties as the ITZ between aggregate and BFPMPC.A multi-scale representative two-dimensional model was established by random aggregate and a two-dimensional extended finite element method(XFEM)to study the mechanical properties of the repair *** simulation results show that the ITZ formed by the interface of BFPMPC and OPC mortar and basalt aggregate is the most vulnerable to failure,which is consistent with the nano-indentation experimental results.

关键词： Portland cement concrete pavement Interfacial transition zone Magnesium phosphate cement Repair interface Nanoindentation Mechanical properties and characteristics

Temperature Field of PC Box Girder Bridge Based on GPRS Temperature Collection System

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Wuhan University Journal of Natural Sciences 2015年第3期20卷 269-276页

作者： YANG Zeying LIU Jing QU Jianbo ZHOU Xiangshan LI Lixin School of Civil Engineering Shandong University Highway bureau of Shandong Province transportation bureau of Jiaxiang County Highway bureau of Yantai city

In order to study the temperature distribution and the corresponding temperature effects on pre-stressed concrete（PC） curved box girder bridge in Shandong Province, this paper builds and adopts an automatic remote real-time temperature collection system to collect temperature data on site, and further uses the software ANSYS for analysis. Based on the comparisons between the measured data and the simulation results, the following conclusions can be drawn： 1 Our temperature monitoring system is reliable; 2 The corresponding measured data of the web plate and flange plate exposed to the sun, vary more severely than that at other positions, so these plates need higher standard design and construction requirements; 3 In the cold wave where still is sunshine, the box girder temperature effect behaves as sine-like curve.

关键词： bridge engineering concrete curved box girder bridge temperature distribution and temperature effect measured data and finite element analysis

Bi-level programming model for reconstruction of urban branch road network

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Journal of Central South University 2009年第1期16卷 172-176页

作者：史峰黄恩厚陈群王英姿 School of Traffic and transportation Engineering Central South University Planning bureau of Nanning city College of Civil Engineering Hunan University

Considering the decision-making variables of the capacities of branch roads and the optimization targets of lowering the saturation of arterial roads and the reconstruction expense of branch roads, the bi-level programming model for reconstructing the branch roads was set up. The upper level model was for determining the enlarged capacities of the branch roads, and the lower level model was for calculating the flows of road sections via the user equilibrium traffic assignment method. The genetic algorithm for solving the bi-level model was designed to obtain the reconstruction capacities of the branch roads. The results show that by the bi-level model and its algorithm, the optimum scheme of urban branch roads reconstruction can be gained, which reduces the saturation of arterial roads apparently, and alleviates traffic congestion. In the data analysis the arterial saturation decreases from 1.100 to 0.996, which verifies the micro-circulation transportation's function of urban branch road network.

关键词： branch road reconstruction bi-level programming model micro-circulation traffic

Special Emergency Resources Preallocation Concerning Demand Time for Tunnel Collapse

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International Journal of Disaster Risk Science 2023年第1期14卷 113-126页

作者： Xia Li Yuewen Xiao Jiaxuan Li Haipeng Wang Eryong Chuo Haili Bai School of Civil and transportation Engineering Hebei University of TechnologyTianjin300401China Qingdao Municipal Engineering Design and Research Institute Qingdao266061China Dongying city transportation bureau Dongying257000China Tianjin Institute of transportation Science Tianjin300074China

Lacking timely access to rescue resources is one of the main causes of casualties in tunnel *** provide timely rescue,this study proposed a multi-objective preallocation model of special emergency resources for tunnel collapse based on demand ***,multiple coverage,and cost-effectiveness are taken as the key objectives of the model;the demand time service range is used as a coverage decision factor considering the unique nature of tunnel *** weight of potential disaster-affected points and other general factors are also considered in this model in order to thoroughly combine the distribution of disaster points and service ***,we take 15 main tunnel projects under construction in China as an *** the relative proximity to the ideal point of the selected optimal schemeε_(a)is smaller than 0.5,we will adjust the weight of three objectives and reselect the optimal scheme untilε_(a)>*** with the not preallocated case,the number of rescue rigs needed is reduced by 8.3%,the number of covered potential disaster-affected points is increased by 36.36%,the weighted coverage times are increased from 0.853 to 1.383,and the weighted distance is significantly reduced by 99%when the rescue rigs are preallocated,verifying the feasibility and superiority of the proposed model.

关键词： China Demand time Emergency resources preallocation Special emergency resources Tunnel collapse

Field Application of Mulberry Straw Arch in Ecological Bank Revetment

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Journal of Renewable Materials 2022年第10期10卷 2607-2621页

作者： Xiaojuan Yu Chao Liu Quan Hua Xiaohui Wang Yongbin Li Geotechnical Research Institute Yancheng Institute of TechnologyYancheng224051China Yancheng city Channel Management Office Yancheng Transportation BureauYancheng224051China

With the growing level of awareness and increasing demand for environmental protection,timber pile revetments with significant ecological effects have experienced increasingly wide application in *** current timber pile revetment system has two problems:continuous dense piles have high construction costs and require large timber consumptions,while the discrete pile-bamboo fence systems have poor retaining *** these problems,an original revetment structure form is proposed:a discrete pile-mulberry straw arch *** investigate the mechanical properties of the mulberry straw,some mechanical tests are conducted on mulberry straw and its arch *** is found that the average compressive strength of mulberry straw is 2.30 MPa,the bending strength is 20.08 MPa and the shear strength is 2.99 MPa;considering the structural characteristics of arches,mulberry straw arches have a high bending strength,which affords immense potential for their application in revetment ***,by doing field study of the discrete timber pile-mulberry straw arch structure for bank revetment,it is found that the arch height of the mulberry straw arch changes 1.4–1.6 cm after 489 d *** soil settlement before the straw arch is 0.13–0.18 cm and the settlement of the pile is 0.66–0.72 *** with bamboo fence structure,the cost of using mulberry straw arch structure as revetment material can save up to 27.07%.Therefore,the discrete timber pile-mulberry straw arch has a rational and stable structure that provides effective support for protecting the riverbank and the toe of gentle slopes and effectively prevents the collapse of bank slopes in the *** new revetment structure proposed in this paper has signifi-cant ecological and economic effects,is easy to construct and feasible for standard production,and consequently has great application potential.

关键词： Mulberry straw arch ecological bank revetment field test

Camellia oil trait and DIA quantitative proteomics analyses reveal the impact of harvesting time on the oil content and quality of the late-maturing cultivar ***‘Huaxin’

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Food Quality and Safety 2022年第4期6卷 521-533页

作者： Jugang Wang Xiaomin Gao Min Liu Jianxin Li Hong Yang Zuhua Wang Lilin Yang College of Agro-forestry Engineering&Planning Tongren UniversityTongrenChina Guizhou Provincial Education Department Engineered Research Center for Innovation and Utilization of Oil Camellia Germplasm Resources Tongren UniversityTongrenChina Guizhou Provincial Key Laboratory for Biodiversity Conservation and Utilization in the Fanjing Mountain Region Tongren UniversityTongrenChina

Objectives:Harvesting fruits prematurely is a serious problem in many Camellia oleifera‘Huaxin’*** views of dynamic alterations in central metabolism associated with the oil content and oil quality of this cultivar at different harvesting dates were *** and Methods:Oil trait analysis was performed in conjunction with data-independent acquisition proteomics analysis using kernels harvested at three time *** were taken from different years and locations to verify oil trait changes,and parallel reaction monitoring(PRM)was performed for some pivotal proteins to validate changes in their ***:Samples harvested at 6 d after the recommended harvesting date had the highest contents and best fatty acid composition of Camellia oil.A total of 614 differentially accumulated proteins were detected in three pairwise *** days prior to the recommended harvesting date,the maximum expression of ribonucloprotein,helicase ATP-binding domain-containing protein,and glycerol kinase and the highest seed moisture content were *** highest mitogen-activated protein kinase 6,very-long-chain 3-oxoacyl-CoA reductase and stearoyl-CoA desaturase expression appeared on the recommended harvesting date.A delayed effect was observed for proteomic and oil trait *** trait and PRM validations indicated that the results were highly ***:The current data strongly suggest that in Guizhou Province,‘Huaxin’cannot be harvested earlier than the recommended harvesting date;appropriately delaying the harvesting time can improve the ultimate production and quality of Camellia oil.

关键词： Oil Camellia harvesting time proteome fatty acids delay effect

Establish Albumin-creatinine Ratio Reference Value of Adults in the Rural Area of Hebei Province

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Chinese Medical Sciences Journal 2016年第1期31卷 23-30页

作者： Qiao-jing Liang Wen Huang Guo-juan Zhang Ning-li Wang Department of Nephrology Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical University Beijing Institute of Ophthalmology Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical University

Objective To establish albumin-creatinine ratio （ACR） reference value of the rural population in Hebei province. Methods This study enrolled 5154 participants. By excluding subjects with hypertension, diabetes, dyslipidemia, cardiovascular and cerebrovascular diseases, kidney diseases, and overweight condition, as well as those with an estimated glomerular filtration rate （eGFR）（60 ml/（min· 1.73 m^2）, apparently healthy subjects （1168） were selected. Urine albumin was measured by using the immunoturbidimetic method, serum creatinine was measured by using Jaffe＇s kinetic method on a morning spot-urine sample, and ACR was calculated. The 95th percentile of ACR in the healthy subjects was used as the normal upper limit. Results The normal upper limit of ACR was 28.71 mg/g （3.25 mg/retool） for males and 31.85 mg/g （3.60 rag/retool） for females. Based on this ACR reference value, the age-gender standardized prevalence of albuminuria in the rural areas of Hebei province was 12.9%. Conclusion The ACR reference value in the rural of Hebei province is higher than that of the Western population.

关键词： albumin-creatinine ratio albuminuria chronic kidney disease

Efficient Technique of Rapeseed and Morchella *** in Mountainous Areas

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Medicinal Plant 2022年第1期13卷 7-10页

作者： Wenjun SONG Haiping DENG Yan SHI Dan LIU Xiaosong LI Kaiguo LIU tongren Academy of Forestry Tongren 554300 China tongren Academy of Agricultural Sciences Tongren 554300 China Bijiang District bureau of Agriculture and Rural Affairs Tongren 554300 China

Aiming at the climatic characteristics of more rain and high humidity and cultivation habits of rapeseed in tongren area,in terms of rapeseed and Morchella ***,excellent varieties suitable for the local climate were selected,the formulas of culture substrate and nutrition bag were optimized to produce high-quality strains,soil pests were prevented and controlled,rapeseed was transplanted in time,Morchella *** sown in ditches,nutrition bags were placed simultaneously,thick soil was covered and fruiting ditches were left,and stress was arranged to promote growth of *** production cycle was 90-100 *** yield of Morchella *** 2250-3375 kg/ha,with a net profit of 6000-10000 yuan.

关键词： Morchella spp. Rapeseed Interplanting Nutrition bag Stress Density of conidial layer

Effects of odd-even traffic restriction on travel speed and traffic volume:Evidence from Beijing Olympic Games

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Journal of Traffic and transportation Engineering(English Edition) 2016年第1期3卷 71-81页

作者： Ruimin Li Min Guo Institute of transportation Engineering Department of Civil EngineeringTsinghua UniversityBeijing 100084China Beijing Traffic Management bureau Beijing 100037China

This paper reports the effects of using an ＂odd and even＂ traffic restriction policy in Beijing during the 2008 Olympic Games. Based on data from 529 traffic detectors on the expressway network and some main arterials in Beijing, China, a comparative analysis has been carried out on the following parameters： the total traffic volume within the expressway network, the total traffic volume on different ring expressways, the traffic volume and speed of a freeway segment, and an arterial street before and after the implementation of the traffic restriction policy. The results show that during the traffic restriction period, although more than 50% of vehicles were forbidden to travel in Beijing, the traffic volume was only reduced by 20%-40% while the travel speed had been increased by 10%-20%. This suggests that such traffic restriction policy may be an effective shortterm management measure in dealing with increased transportation demand and congestion during major events, such as the Olympic Games. Results also indicate that vehicle travel demand does not decrease with the same proportion as the total vehicles forbidden, at least for the expressway and main arterials in a city.

关键词： Traffic demand managementTraffic restriction policyComparative analysisTraffic detection system