bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of Metal Organic Framework Material MIL-101
Authors: Zhang Xiaotong , Li Fangqin , Ren Jianxin , Feng Haijun , Hou Xin , Ma Chuang
Published: July 2019

MIL-101 is a typical metal-organic framework. Mil-101, like the other metal-organic frameworks (MOFs) is a material with high porosity, large surface area, adjustable micro-pore size, and easy functional structure. Contrary to the most MOFs, Mil-101 has a high hydrothermal stability. All of the characteristics collectively make MIL-101 a good candidate for a catalyst support. In this paper, the synthesis methods of MIL-101 materials have been reviewed. It is pointed out that the hydrothermal synthesis method has many problems such as complicated process, many organic waste liquid and low yield. The room temperature fast synthesis method has the potential to provide industrialized production of MIL-101 with its unique advantages.
Research on customers’ willingness to participate in express package recycling
Authors: Cao Xing , Liu Chengshan
Published: July 2019

The rapid development of logistics and electronics industry has produced a large number of express packaging garbage, which is gradually destroying the environment and wasting resources, the implementation of express packaging recycling has become the key, but consumer participation in express packaging recycling intention is not strong. Based on the theory of planned behavior, social exchange, perceived trust and situational factors, this paper constructs a model of influencing factors of consumers’ willingness to participate in express packaging recycling, and makes an empirical analysis using structural equation model. The results show that recycling attitudes, perceived behavior control, perceived benefits, convenience and policy propaganda have a significant positive impact on consumers’ willingness to participate in express packaging recycling. Subjective norms, perceived trust and perceived benefits have a certain impact on recycling attitudes.
Chloride Distribution Feature in Surface Layer of Cementitious-based Materials under Mere Cyclic Wetting and Drying Action
Authors: Chang Honglei , Qu Mingyue , Cheng Mengying , Liu Jian
Published: July 2019

Chloride transport under wetting and drying environment is very complicated. A lot of research has reported maximum phenomena in chloride profiles under such environment. Considering the fact that most specimens in which chloride maximum was detected before either had inhomogeneous surface (might be influenced by skin effect) or were exposed to natural environment (might be influenced by rain washing), this study aims to reveal chloride distribution under mere wetting and drying condition in cement-based materials. The chloride distribution results in the surface layer of specimens with different water to binder ratio (W/B) detected by silver nitrate titration method (SNT), ion chromatography method (IC)and electric probe micro analysis (EPMA) present a fact that: maximum phenomena occur in all specimens under four wetting-drying regimes, no matter in paste or mortar, in free or total chloride, and whether with slag (SL) and fly ash (FA) or not. It suggests that mere wetting and drying action can incur chloride maximum phenomenon without the attendance of skin effect and rain washing, though sometimes confined by the accuracy of testing method, the position of maximum phenomenon can not be presented.
Assessment and Design of Critical Infrastructures against Intentional Attacks Based on Degraded States Vulnerability Methodology
Authors: Geng Hao , Lu Hao , Huang Mu , Sun Shanzheng
Published: July 2019

A crucial issue in today’s counterterrorism environment is how to assess critical infrastructure damage and develop a more appropriate design rapidly against intentional attacks, since it has become unacceptable to ignore the high impact of disruptions caused by these attacks. Degraded states vulnerability methodology (DSVM) is used to explore the vulnerability analysis and design method of critical infrastructures. After the terrorist attack, the damage status of the components at all levels of the target is quickly determined, and the probability of component level damage is simulated. Using this method to judge the functional damage condition and improve the planning and design under multi-hit. Respond quickly to the damage effect of each hit, and put forward multi-hit’s degraded states transition tables and state-effect tables. It provides the basis for rapid assessment, planning and design of critical infrastructure in modern local wars where terrorists are more intensive and frequent.
Above-threshold ionization of hydrogen atoms in a two-color laser field
Authors: Guo Zhijian
Published: July 2019

By using the method of electron wave packet interference, we investigate the above-threshold ionization (ATI) of hydrogen atoms in a linearly polarized two-color laser pulse (λ
1 = 800 nm and λ
2 = 400 nm). Firstly, using the strong field approximation (SFA) with the time window function, we obtain the intracycle interference and intercycle interference patterns of hydrogen atoms in a 10 fs laser pulse, and it is found that the general characteristics of two-dimensional photoelectron momentum spectrum are formed by the interplay of the intracycle interference and intercycle interference, and the side rings in two-dimensional photoelectron momentum spectra originate from intercycle interference. Subsequently, we calculate the two-dimensional photoelectron momentum spectra of hydrogen atoms by SFA in full pulse. When the relative phase ϕ = 0, the intracycle interference and intercycle interference fringes in two-dimensional momentum spectrum are symmetrical, and when the relative phase is ϕ=0.5π, the intracycle interference fringes in the two-dimensional momentum spectrum are obviously asymmetrical. The results show that ionization is vitally dependent on relative phase of two laser pulses in two-color laser filed.
In-depth study of the key factors affecting the degradation of antibiotics by carbon nitride and its modified photocatalytic materials
Authors: Qiang Ning , Shi Tianzhe , Liu Tao
Published: July 2019

In this paper, the method of thermal copolymerization is used to synthesize graphite phase carbonitride with urea as precursor, and thermal copolymerization of urea and salicylic acid to form modified carbon nitride. Through a series of experiments to explore the influencing factors of photocatalytic degradation of antibiotics by carbon nitride and its modified photocatalytic materials under different conditions, the suitable experimental and applied catalytic conditions were proposed to provide theoretical support for scientific research and practical application.
In-depth study of desorption kinetics in adsorption process
Authors: Qiang Ning , Shi Tianzhe , Cao Yiqi , Miu Haichao , Liu Tao
Published: July 2019

In this paper, open-loop desorption experiments were carried out by hot gas sweeping. The effects of different concentrations of methylene chloride and temperatures in the sweeping gas on the desorption process were investigated from three perspectives: average desorption rate (

V
¯

30

,

V
¯

9

), instantaneous desorption rate (Vmax) and desorption kinetics. It was concluded that the maximum instantaneous desorption rate could better represent the desorption rate required by the experiment at different sweeping concentrations and temperatures. The maximum instantaneous desorption rate Vmax increased with the rising temperature and decreased with the increasing concentration of inlet methylene chloride. The concluded law was the same as the average desorption rate (

V
¯

30

) of 30 min. Thereinto, the temperature had a significant influence on Vmax. As the temperature increased, the concentration of inlet methylene chloride also inhibited the maximum instantaneous desorption rate Vmax more obviously. This provided important reference data for the optimization design of desorption equipment in the activated carbon adsorption process.
Multi-agent revenue distribution model of VPP based on game theory
Authors: Wang Xuanyuan , Zhang Hao , Shi Jianlei , Liu Zhen , Liu Dunnan , Wang Jiani
Published: July 2019

VPP contain multiple investment entities. There are cooperation and competition relationships among different entities. It is necessary to study the problem of income distribution among multiple entities. Firstly, the multi-agent investment income model of VPP is analized, and the VPP income function is determined. Secondly, based on cooperative game theory, the Shapley value method is used to construct a multi-agent revenue model allocation model for VPP. Finally, select typical scenarios for measurement and analysis to verify the validity of the model.
Effects of Compound Sweep and Lean on the Aerodynamic Performances of Transonic Centrifugal Impellers
Authors: Zhao Huijing , Lu Xiang , Zhao Guanhui , Ma Rui
Published: July 2019

The blade lean and sweep has a significant effect on the centrifugal compressors performance. This paper modifies the blade leading edges of two transonic centrifugal impellers with two compound sweep and lean (CSL) methods: the blade tip forward sweep with a negative lean (SFB), the blade tip backward sweep with a positive lean (SBB), and the CSL effects are numerically studied. For the unshrouded impeller, the SFB improves the highest isentropic efficiency and total pressure ratio. The SBB decreases the total pressure ratio and almost has no effect on the isentropic efficiency. The SFB expands the stall margin. Conversely, the SBB decreases the stall margin. The CSL effects on the shrouded impeller are less obvious compared with the unshrouded impeller. By analyzing the flow field, it is found that, the CSL has important effects on the shock, the accumulation of low momentum fluid and the blade loading near the blade leading edge for unshrouded impeller and shrouded impeller. Since the CSL effects on the stall margin of the unshrouded impeller are associated with the blade tip loading and tip clearance leakage flow, the CSL does not influence the stall margin of the shrouded impeller without a tip clearance.
Research on mine acoustic wave transmission technology
Authors: Gao Jun , Ma Hongwei , Shi Zhijun
Published: July 2019

In view of the present coal mine underground majority drilling construction still uses the non-directional drilling technology in present situation, it is proposed to use the propagation characteristics of sound waves in acoustic drill rods to study the mining data transmission technology based on acoustic wave transmission to make up for the existing drilling while drilling. Insufficient transmission mode by studying the propagation characteristics of sound waves in the drill pipe, revealing the law of amplitude attenuation and residual wave variation of the acoustic signal in the drill pipe, determining the signal transmission frequency and amplitude; considering the actual working conditions of the coal mine, designing a rare earth based the explosion-proof transducer of giant magnetostrictive material is used as the signal source. Finally, the reliability of the transmission scheme and signal source is verified by the signal transmission simulation test.
Optimization of Hydrolyzed Crude Extract from Tartary Buckwheat Protein and Analysis of Its Hypoglycemic Activity in Vitro
Authors: Tao Ting , Pan Di , Zheng Ya Ying , Ma Ting jun
Published: July 2019

Tartary buckwheat was used as substrate for enzymatic hydrolysis to prepare a crude extract of tartary buckwheat protein, hydrolyzed by alcalase to simulate digestion in vivo. On the basis of single factor experiment, buckwheat protein hydrolysis was served as the response value. By Box-Behnken experimental, the optimum conditions were determined as volume of enzyme 40.61 U/g, temperature 46.16°C, time 20.80 min. Under these conditions, the actual degree of hydrolysis of the tartary buckwheat protein could reach to 57.71%, in good agreement with the predicted value (57.69%), and the inhibition of α-amylase activity was 78.69%, respectively.
Study on the Sedimentary Microfacies Subdivision Standard of Type ii B Reservoir in Sanan Development Zone
Authors: Junming Sun
Published: July 2019

At present, the object of tertiary oil recovery and development in Sanan development zone has been transferred to type ii B reservoir, aiming at the current situation that the development effect is not ideal at the stage and the characteristics of more heterogeneity of type ii B reservoir. The sedimentary microfacies subdivision of type ii B reservoir was carried out, and the sedimentary microfacies subdivision standard was established by combining qualitative and quantitative methods, which provided a strong support for further improving the quality and increasing the efficiency.
Mine acoustic wave signal generator
Authors: Gao Jun , Ma Hongwei , Zhu Yinda
Published: July 2019

Based on the requirement of mine acoustic wave technology for the signal generator, this paper aims to explore the key factors affecting the amplitude of the output acoustic signal of rare earth giant magnetostrictive materials (RE-GMM), including bar size, magnetic field strength and pre-stress in order to set an optimal plan based on the influence of various factors on output signal amplitude. This paper establishes a test platform for measuring the output performance of the acoustic signal generator and to test the prototype. Result verifies the correctness of the scheme.
Mode Study on the Circulation Sharing of Logistics Turnover Box on New Agricultural Products
Authors: Miao Ye , Zhang Pin , Ma Yanmei , Fu Wentao , Wang Chen
Published: July 2019

In terms of ecological environment protection, the to-circle-box circulation sharing model responds to national policies, meets the requirements of energy conservation and emission reduction in the “Twelfth Five-Year Plan”, and conforms to the theory of low-carbon economy. From the perspective of market development, the demand for totes in the cyclical sharing model will increase. The prospect of tote leasing is very broad, as there are no special large toll collectors in the current market. This paper analyzes the development trend of Chinese logistics turnover box cycle sharing, proposes the operation process of the new logistics turnover box cycle sharing mode, and builds the agricultural information logistics container rental sharing information platform. The economic benefit and social benefit of the cycle box circulation sharing mode and ecological benefits are analyzed.
Research on the Motivation and Path of New Logistics Development under the New Retail Era
Authors: Wang Rixin , Dan Liang , Da Xu , Huo Feida , Wang Faquan
Published: July 2019

New retail is a retail model based on the Internet, using big data, cloud computing and other technologies to upgrade the production process, circulation and sales of commodities, and deep integration of online and offline and smart logistics. The new retail has aroused widespread concern from all walks of life, and the new retail industry has sprung up, which has also promoted the development of new logistics. By analyzing the relationship between new retail and new logistics development, the article explores the relationship and difference between new logistics and traditional logistics, analyzes the motivation of new logistics development, and proposes relevant measures to promote the development of new logistics.
Development Countermeasures on Container Multimodal Transport of Railway in China
Authors: Shi Yujiao , Zhang Nina , Shang Yan , Zhang Zetong , Li Yiyang , Li Zheng , Shi Yujiao
Published: July 2019

With the national “One Belt and One Road” strategy put forward, multimodal transport has become the key to break through the bottleneck of China’s comprehensive transport service capacity. In order to speed up the construction of modern integrated transportation system and promote the logistics industry to reduce costs and increase efficiency, this paper analyses the problems existing in the development of China’s railway multimodal transport and analyses the opportunities for the development of China’s railway container multimodal transport from four aspects. Finally, the paper puts forward some countermeasures for the development of multimodal transport, which can improve the efficiency of multimodal transport organization, realize the smooth connection of different modes of transport, and promote the cost reduction and efficiency increase of logistics industry.
Exploration of the basic flight mode of a two-axis aircraft
Authors: Liu Xuetao
Published: July 2019

In recent years, drones have been widely used in military and civilian applications. Among them, multi-rotor UAVs have functions such as taking off and landing vertically, hovering and flighting in high speed. It is simple to operate, safe, reliable and highly serviceable. It has received great attention from people and has become a research hotspot in recent years. However, it has obvious defects in endurance performance and load capacity, and the two-axis aircraft is one of the methods to solve the problem. Therefore, this paper explores the structural form of the two-axis aircraft and the flight principle of the basic flight mode.
Treatment of wastewater from alumina plant by electrodialysis
Authors: Hu Biao , Mu Zhi Duan
Published: July 2019

The alumina plant emits a large amount of production wastewater every day, which causes serious pollution to the environment and also seriously wastes water resources. In response to this problem, the electrodialysis method was used to treat and recycle the wastewater from the alumina plant. The test adopts cyclic desalination. The volume of fresh water controlled during the test is 4 times of the volume of concentrated water, that is, the recovery rate of wastewater is 80%. The constant pressure, constant current operation and the desalination effect of fresh water inlet line speed under constant pressure conditions are respectively carried out. the optimal operating conditions of the system was determined. Using 100 V terminal voltage to control fresh water and concentrated water inlet line speed of 5 cm / s, three parallel desalination tests were carried out. The results showed that the salt content of fresh water was less than 500 mg/L. and the water quality meets the industrial water requirements of the alumina plant. The energy consumption per unit of water production is relatively low, less than 1.75 kw·h/m3 fresh water, which is beneficial for economic development.
Research Progress in Seismic Structural Design of Bridges Crossing Strike-slip Faults
Authors: Shi Jingxian , Cheng Yingjie , Liu Xun
Published: July 2019

Bridge structure is an important lifeline project. Bridge structures across strike-slip faults have great risk of damage during earthquakes. It is of great significance to ensure that they can operate safely and reliably during earthquakes. Firstly, this paper introduces the basic characteristics of strike-slip faults; secondly, the main earthquake damage of bridge across fault is summarized, as well as the theoretical research status and existing problems of this kind of bridge; finally, the key problems of the bridge across strike-slip fault need to be studied are prospected.
Stability Study of Poly Nitro Substituted Compounds of cis-syn-cis-2,6-Dioxodecahydro-lH,5H-Diimidazo[4,5-b:4’,5’-e] Pyrazine
Authors: Yang Tongtong , Xu Zhibin , Meng Zihui
Published: July 2019

Due to their excellent performance both in density and high detonation velocity, poly nitro substituted cis-syn-cis-2,6- dioxodecahydro-lH,5H-diimidazo [4,5-b:4’,5’-e] pyrazine derivatives (2-5) attract our focus. The stabilities study showed that the sensitivity of these compounds is increasing with more nitro groups substituted. Although compound 5 with six nitro groups exhibits the most excellent detonation velocity, it is very sensitive to friction and impact. As isomer to each other, compound 2 and 3 showed not only low sensitivity but also good thermal stability with similar detonation performance to RDX and HMX. It suggests that they are potential energetic materials.
Regulation of Protein Interaction in Protein Nuclear Transport and Its Function
Authors: yuyi Fang , qingqing Li , Huakun Wang
Published: July 2019

Protein nuclear transport is an important process in eukaryotic cells, and is closely related to the normal function of cells. Normally, protein nuclear transport is accomplished by nuclear receptor mediation, which requires the participation of multiple proteins. Therefore, protein nuclear transport cannot be separated from the interaction between proteins. In this paper, the relationship between protein interaction and protein nuclear transport is studied, and its effects on cellular and physiological functions are analyzed from many aspects.
A novel liquid precipitation route to synthesize high-quality cobalt carbonate with low chloride ions concentration
Authors: Guo Miaomiao , Xi Xiaoli , Li Sen , Long Xiaolin , Nie Zuoren , Xu Kaihua
Published: July 2019

Herein, high-quality cobalt carbonate is synthesized by employing a novel liquid phase precipitation route, where CoCl2 and ammonium bicarbonate solutions are used as the raw material and precipitator, respectively. The morphology of primary and secondary particles and agglomeration due to their nucleation and growth are influenced by the stirring speed, reaction temperature and pH value. Furthermore, the influence of process parameters on physiochemical properties has been systematically studied by measuring apparent density, FSSS particle size, specific surface area and chloride ions concentration. Under optimal processing conditions, i.e., stirring speed of 100 rpm, pH value of 7.0-7.1 and a reaction temperature of 55 °C, the as-synthesized cobalt carbonate rendered an apparent density of 0.74 g/cm3 and chloride ions concentration of 19 ppm. The results reveal that the washing efficiency of chloride ions is affected by the morphology of primary particles and stacking mode of the secondary particle in cobalt carbonate. In general, the higher BET specific surface area of cobalt carbonate results in lower chloride ions concentration.
Application of Thermal Neutron Imaging System in Oil & Gas Field development
Authors: Xu Xiaohu , Fang Huijun , Lin Jingde , Liu Xinwei , Chen Gang
Published: July 2019

The correct identification of oil and gas reservoirs is very important in oil and gas field production. To solve the problem of oil and gas reservoir evaluation in low salinity and low porosity reservoirs, thermal neutron imaging system(TNIS) is introduced. The advantage of TNIS is that it can record a large number of formation information through multiple detectors to obtain imaging documents, allowing intuitive quantitative analysis of formation, and calculate oil and gas saturation through thermal neutron capture cross section, attenuation spectrum and capture spectrum, so as to obtain oil/gas/water distribution near wellbore. In the processing, interpretation and evaluation of thermal neutron imaging logging data, the interpretation model, parameters and criteria are established according to the geological characteristics of lithology and formation water salinity of the target block, which improves the interpretation coincidence rate. Field application shows that thermal neutron imaging logging has achieved sound effects in identifying watered-out zone, potential zone, gas reservoir and residual oil distribution monitoring.
Design of intelligent detection system for high voltage circuit breaker based on functional integration
Authors: Su Yi , Lu Yufeng , Xie Zhibiao , Huang Huimin , Wang Jialin
Published: July 2019

Since there are various preventive test items for high voltage circuit breaker, in this paper, a function-integrated hardware is put forward to reduce the height and wiring times of the test personnel and improve the field work efficiency. Firstly, we comprehensively analyze the electrical test requirements for high voltage circuit breaker. Then we integrate multiple detection projects into one system, taking advantage of the fact that each test project can be merged. These test projects include tests of dielectric loss of circuit breaker, capacitance value, circuit resistance, direct resistance of switching coil, mechanical characteristic, closing resistance and closing time as well as insulation resistance and AC withstand voltage of auxiliary control circuit. Next, we configure the required detection items and relevant parameters before the test. Finally, we complete the whole process, which requires connection and disconnection for only once and will automatically finish all project detection, test data collection and intelligent analysis item by item.
Brief analysis of key issues in the HSE due diligence of LNG point-supply project
Authors: Chuan Ai , Leibin Qin , Mengli Zhang
Published: July 2019

With the increase of national environmental protection and the introduction of favorable policies, LNG point-supply project has achieved rapid development. In order to further optimize the industrial structure and achieve mutual benefit between enterprises, HSE due diligence should be carried out for LNG point-supply project before collecting, merging and purchasing enterprises. On the basis of field investigation, the problems of formalities and site safety existing in LNG point-supply project were mainly analyzed in this paper, and some suggestions were put forward. On the one hand, the project leaders of LNG point-supply should complete the formalities actively to promote the legalization, and strengthen the management and correct problems timely while strengthening communication with owners. On the other hand, investigators should pay attention to the change in national laws and regulations in real time and carry out in accordance with existing laws and regulations.
The Study of Waterflood Stimulation Technology
Authors: Li Ning , Yu Dong-he , Yu Xi , Che Hang , Liu Guo-hua , Mu Hai-lin , Zhang Bin , Zhang Li-na
Published: July 2019

Aiming at the development status of Liuxi Oilfield, waterflood stimulation is studied to improve the development effect. The process is as follows: in begin with, the displacement liquid is injected into the oil well quickly to replenish energy; then the oil well is closed a while to promote oil and water displacement; finally, let the oil well produce under a reasonable system of production. Strong water-wet, high oil saturation, the degree of fracture development and low oil viscosity are the advantages of using waterflood stimulation by analyzing related researches. Based on the reservoir engineering research, numerical simulation method which is about waterflood stimulation is established using Eclipse software. According to the numerical simulation results, assuming that injection rounds is one time, when injection volume is more, the formation pressure rises higher and the liquid sweep is wider and cumulative production is more. At the same time, the degree of stage production is increasing with the closed time lengthen. But it has the most optimum values about the closed time, and the production increase of the degree of stage production becomes significantly slow.
Research and Implementation of QoS Algorithm for 230MHz Power Wireless Private Network
Authors: Shao Weiping , Zhang Ruibing , Fang Jinghui , Chen Jing , Zheng Weijun , Yuan Jing
Published: July 2019

The wireless private network is a key for building an energy Internet and a full-service ubiquitous electric Internet of things (eIoT). It is an important means to get through the bottleneck of power distribution network. Quality-of-Services (QoS) management is the one of the issues that is appeared after using wireless network. With the requirements of power Internet of things, this paper studies the communication needs of different service types in the power grid, proposes a two-stage QoS algorithm based on 230MHz power wireless private network, and solves the problem of prioritizing different service types in the power grid. A new type of wireless communication equipment was developed and tested through the trial network. The test results proved that the algorithm could effectively optimize the QOS processing capacity of the system, and the results met the design expectation. The research result has positive reference value for further evolution of the electric Internet of things.
Hydrate-based desalination process enhanced via graphite
Authors: Li Feng , Yang Yamei , Shi Changrui , Yang Shiying , Chen Zechang , Yang Shihao , Ling Zheng , Song Yongchen
Published: July 2019

Desalination via hydrate processes is a novel and attractive method for desalting seawater. However, it is a great challenge to form hydrates with large amount in a short time, especially in the presence of high concentrations of salts. In this study, we used cheap and easily separated graphite particles to promote hydrate-based desalination. It was confirmed that graphite has no impact on the structures and compositions of cyclopentane hydrates. The dosage of used graphite can dramatically increase the conversion rate of water to hydrate, without degradation of the desalination efficiency. Due to the presence of graphite, the ratio of NaCl solution to cyclopentane has little impact on the conversion rate. A multi-stage desalination via hydrate formation was demonstrated, which can produce high quality freshwater with a purity of 99.76% meeting the drinking water standard. The findings in this study will help to rationally select and design the desalination process based on hydrates.
Analysis of impact of offshore platform pile under the waves and ice load Introduction
Authors: Wang Jun , Wang Liting , Wu Chongfu , Lang Junbiao , Zhang Junning
Published: July 2019

This article uses finite element software to simulate the internal force and deformation of pile-soil under the wave and ice load. The group pile foundation model is simplified in the plane as a single pile affected by other piles.Calculating wave force based on Morison Equation,The effect of wave force and ice load calculated with the measured wave force and ice load on the pile is compared. According to the time history curve, when the absolute value of acceleration is maximum, the curves of the bending moment, axial force, shear and displacement of the pile with the depth of the pile under the action of wave force, ice load and joint force are analyzed, the time history curves of pile top displacement under the combined action of wave force and ice load are analyzed,the displacement time history curves of different positions of piles are compared.Finally, the effect of buried depth, pile diameter and free length on the pile body interaction under the wave force and ice load is analyzed.
On Bearing Capacity of Power Tunnel Angle Steel Brackets
Authors: Jia Liu , Xiaotian Fang , Yi Wang
Published: July 2019

Based on the typical power tunnel project in Guangzhou, a finite element analysis model is established based on full-scale test. The stress, strain and displacement of the support under end load are studied. The results show that the length of the bracket and the thickness of the angle steel have great influence on the bearing capacity of the support, and the relationship between the length and the bearing capacity is basically linear. The model is used to analyze the parameters of the bracket, and the optimal structure form is obtained to achieve the goal of economic and efficient.
Research on Risk Management of Ginza Project
Authors: Zhang Mengfei , Wang Tiedan , Peng Dinghong , Guo Bingxue
Published: July 2019

This paper reviews the basic situation of risk management at home and abroad, starting from the view of project investors, and carries out risk management analysis for specific construction projects in Ginza. Firstly, the concept and classification of project risk management are put forward. Then, the risk management of a city’s Ginza is thoroughly analyzed from four risk management processes: risk identification, risk assessment, risk decision-making and risk monitoring. The whole process of risk management is completed by four procedures, so as to reduce risk losses.
Interaction Analysis of Multiple Cracks Based on the Maximum Shear Stress Criterion
Authors: Jianfeng Xue , Yuelin Sun , Zhenzhong Shen
Published: July 2019

In order to analyse the interaction of multiple cracks in the process of the cracks propagation and penetration, the overlap triple-cracks penetration test was simulated according to the maximum shear stress criterion. The stress intensity factors of the crack tips were calculated by means of element-free method (EFM). The results show that the maximum shear stress criterion can simulate the crack propagation process well. With comparison with the single crack model, the formation mechanism of the wing cracks and the shear cracks, and the interaction between the cracks and its influence on the multi-cracks propagation path were also explained.
On-site Monitoring and Comparative Analysis about Surrounding Rock Pressure Variation with Time in Unsymmetrial Loading Tunnel
Authors: Hu Jiang-chun , Sun Fa-yong , Li Yuan , Cui Li , Ji Meng-jie
Published: July 2019

Bias Tunnes are common seen and it has complicated variation on their surrounding rock pressure. It is crucial for the security and stability of a tunnel to determine the variation law of surrounding rock pressure and on-site monitoring technology. This essay compares the experimental data to the theoretically calculated data of a certain tunnel according to the data from on-site monitoring and theoretical analysis. The result indicates that the real data of surrounding rock pressure of three chosen cross sections is close to the calculated data from grade V surrounding rock. To be specific, the vault and the arch waist are in good agreement. The pressure on the tunnel is obviously unsymmetrial. The data of surrounding rock pressure of arch waist and flank wall on the left side is larger than that on the right side.Also, there is a significant difference between the measured data and calculated data of pressure of horizontal adjoining rock. The horizontal stress of surrounding rock on the bias tunnel is over-released. The measured pressure data on flank wall is much larger than its calculated data.In conclusion, The timbering system should be reinforced in the early stage of construction and the rigidity of timbering system should be chosen carefully. The result of this research can contribute to the tunnel construction design and construction safety in the future.
Analyzing chaotic effect of reinforced concrete pile driving in cohesive soil
Authors: Du Ting , Yan Tiecheng , Liu Liping
Published: July 2019

This paper presents the chaos phenomenon in pile driving. Firstly, the pile wave equation that Smith put forward is used for painting Poincare section, and then the basic features of chaos are obtained. By analyzing the Poincare section, a point with which the ratio of penetration to velocity is the largest is discovered, and that is to say energy consumption is the lowest at this point. Moreover, the relationship between hammer weight and dropping height is proved to satisfy the construction experience of light blow with heavy hammer through curve fitting. So according to the theory, the value of impact force and initial value can change to get the hammer weight and dropping height for different square and circular piles under the lowest energy consumption. The results show it is better to use square piles during driving, and the relationships between square and circular piles with different cross-sections and its impact force on pile top, hammer weight and dropping height satisfy a certain function equation, respectively. Hence, the corresponding hammer weight and dropping height can be selected to save energy consumption and reduce the cost during construction according to their functional relation.
Research on Tunnel Risk Control and Evaluation Index Based on Fuzzy Theory
Authors: Wen Fei , Yin Zihan , Zhou Ying
Published: July 2019

In recent years, many large scaled tunnels, like the Kouksa Tunnel, with complicated construction have emerged in China. The multiple factors, including intricate topography and weather conditions, all make the potential risks highly uncontrollable during tunnel excavation. The researching group made comprehensive assessments to geological risks of the Kouksa Tunnel through the fuzzy theory, and drew the conclusion that its risk belonged to level three, as a medium one. By assessing geological risks, it will be helpful for the construction unit to take measures to prevent high-risk geological disasters and ensure the safety of tunnels.
Preparation and Properties of Carbon Nanotube-Ag/AgCl Electrode for Marine Electric Field Test
Authors: Chen Wenbo , Song Yusu , Li Hongxia
Published: July 2019

The carbon dioxide was used as the material to modify the Ag/AgCl marine electric field electrode, and a new type of marine electric field detecting electrode was designed and manufactured. The surface morphology observation, electrochemical performance, electrode self-noise and range stability time were tested. The result shows that the specific surface area of the Ag/AgCl electrode increases greatly after the addition of carbon nanotubes and the range stability time is shortened. The range is small and the exchange current density become larger. It shows good electrochemical performance. Howeve, its electrode self-noise is too large, which is not suitable as a marine electric field detecting electrode.
Soil Parameters’ Influence on the Mechanical Behaviour considering Boundary Condition
Authors: Xu Binbin , Zhang Naishou
Published: July 2019

In this paper, how to determine the soil parameters and initial values employed in the numerical calculation using experimental results is talked over in detail. The results of the triaxial compression tests and one-dimensional tests for undisturbed and disturbed samples are utilized step by step to modify the numerical results. It is found that there are several steps to model the whole procedure of sampling from the ground to the experiment equipment. Therefore, the step of taking the soil samples out from underground, which is assumed to be under the undrained condition accompanying with unloading process until the deviator stress becomes zero, is always ignored in the research.
Static Load Test Study on Long-span Continuous Rigid Frame Bridge with V-shaped Pier
Authors: Zhang Fei , Wang Yan
Published: July 2019

Taking the main bridge of the shuidong bridge in Youxi country of Fujian province as background, this paper develops the static characteristic analysis and static load test study on long-span prestressed continuous rigid frame bridge with V-shaped pier. By the analysis and comparison between the measured data and FEA results, it evaluates the working condition of the bridge. The results show: Firstly,each evaluation indicator tested meets the requirements of “Test methods for large-span concrete bridges” Secondly, the strain efficacy coefficient of measured points in top plate of each control section is within 0.65∼0.74, and that of the measured points in bottom plate is within 0.64∼0.73, the residual strain of the measured points is less, therefore, the safety stock of the bridge is sufficient, and it is on the flexible working condition basically; Finally, the measured value and the theoretical value of deflection curves along the longitudinal bridge is compatible, the efficacy coefficient of vertical deformation is within 0.55∼0.85, and the severity of the practical structure is more.
Providing strategic method to increase performance in execution and management of high-rise building
Authors: Dezhkam Majid , Xue Suduo , Liu Zhansheng
Published: July 2019

In current situation, high- rise building projects execution seems difficult issue. These problems cause to increase duration, possible delay, and increasing project costs. The main goal of this research is prediction of possible accidents in respect of intellectual, behavioral and structural dimensions which establishes various problems such as time, cost, quality and etc in high-rise building execution. Therefore, it should be provided a model which can make suitable and on time various decisions and strategies in least of possible time and cost in case of satisfying impact episodes during project execution and can control deviations and manage executive plans in regard of suitable reliable performance for projects. This article is applicable method in regard of goal and is descriptive- exploratory method in regard of method and form. First, key activities in project are evaluated. Then, interior and exterior environmental factors, duration and the cost of project execution are considered by their impacts to each other, current obstacles in project execution are identified and studied in frame of professional variables of executor organizations. Finally, the technique of partial minimum squares in combination of meaningful non-parametric tests are approved by using Azar board Company (high rise- building company) engineers as statistical society.
Method for evaluating user-side flexible device access to power grid
Authors: Zhang Ke , Gong Taorong , Shi Kun
Published: July 2019

In this paper, the benefit model of energy saving and emission reduction for electric vehicles and fuel vehicles are established, the situation of energy consumption and carbon emission between the two sides were comprehensively analyzed. Then, the reliability model of distribution network was established. Based on the theory of peak-valley time-of-use electricity price and V2G market regulation agreement, the reliability of connecting electric vehicles to distribution network is evaluated accordingly. The results show that the energy consumption of electric vehicles is much lower than fuel vehicles and the economy is better. For example, according to 2017 data, more than 130,000 electric vehicles in Beijing can save up 70,000 RMB per kilometer during peak hours. Reasonable connection of electric vehicles to power distribution network can effectively reduce carbon emissions and has remarkable environmental protection effect. Compared with disorderly charging of electric vehicles, V2G market with peak-valley time-of-use electricity price can obviously improve the stability of the system.
The Knowledge Map of Marine Energy
Authors: Lyu Shuran , Wang Wanqing , Wang Chunxue , Zhang Jiayi
Published: July 2019

In order to analyze the research hotspots of marine energy, the Citespace III software was used to visually analyze marine energy. The database was collected on the criteria of marine energy as the keyword, and time span extended from 2007 to 2016 on the basis of the “Web of Sciencetm core collection database”. The scientific knowledge maps analysis of marine energy has been conducted based on the Citespace III software, and analyzes the active countries/regions, institutions and research hotspots in related research fields. Active countries/regions, institutions and research hotspots of relevant research areas have been studied, and University of Chinese Academy of Sciences is at the first place of whole research institutions in marine energy field. Keywords co-occurrence analysis results show that coast, corrosion, kinetics, evolution and sediments have the highest centralities which are the focal keywords in marine energy research field. The results of the co-citation analysis show that wave energy, tidal stream energy, tidal stream turbines, and the microalgae biofuels are the hotspots in marine energy research field.
Application Research of GPR in Quality Detection of Urban Underground Jacked Pipes Construction
Authors: Yang Tianchun , Dai Shixin , Deng Hanyang , Xu Degen , Wang Qiren
Published: July 2019

Nowadays, pipe jacking method is usually adopted in the construction of urban underground pipelines. In order to ensure the construction quality of pipe jacking method, geophysical non-destructive prospecting methods are used for detecting the compactness around the jacked pipes. Based on the theory of ground penetrating radar (GPR), the void models of jacked pipes with two different materials (i.e. cement pipe and steel pipe) were established, and the finite element method was used to simulate the 2D forward modeling of GPR. At the same time, combined with the urban underground jacked pipes construction project in Xiangtan city, Hunan province, China, GPR was used to carry out field prospection of the quality of jacked pipes construction. The results of forward simulation and practical applications show that good results can be obtained when GPR is used to detect the construction quality of cement pipes, which is the same as that of using GPR to detect the construction quality of tunnel. But the collected signals are not effective when the steel pipes are detected, which is because the radar signal cannot penetrate the steel pipe, and there are multiple reflections between the radar antenna and the pipe wall. Therefore, new non-destructive prospecting methods are needed for void detection of steel jacked pipes.
Experimental study into turbulent characteristics of airflows under stratum ventilation with pulsating air supply: comparison to steady air supply
Authors: Tian Xue , Li Bozheng , Cheng Yong
Published: July 2019

Stratum ventilation is more energy-efficient than conventional ventilation strategies, whereas its thermal comfort can be further improved. Compared with steady airflows, dynamic airflows are capable of improving thermal comfort. Turbulent characteristics of airflows can affect human thermal comfort. This study aims to investigate the turbulent characteristics of airflows in the occupied zone under stratum ventilation with pulsating air supply, which can produce dynamic airflows. The turbulent characteristics were compared with that under conventional steady air supply. Experiments were conducted in a classroom mock-up using stratum ventilation. Five cases, namely, one with steady air supply and four with pulsating air supply were designed. The turbulent intensity (Tu) and power spectrum of air velocity signals were analysed. The results showed that the Tu of the airflows in the occupied zone under pulsating air supply was greater than that under steady air supply by 10-15%. Power spectrum density exponents (β) of airflows under the two air supplies fluctuated within the same range of 0.5 to 1.2. However, the power spectrum density function showed different distributions on low frequency area. The turbulent characteristics of airflows created by pulsating airflows may provide better thermal comfort.
Characteristic Research on the Generation of Ozone Using Dielectric Barrier Discharge
Authors: Du Zhehua , Lin Xin
Published: July 2019

Ozone has been widely used in many fields due to its strong oxidation ability. Under the conditions of the experiments, the results are as follows: With an increasing applied voltage, both ozone concentration and ozone generation rate increase, while ozone generation efficiency increases at first, reaching peak value, then decreases slowly; With an increasing gas flow rate, ozone concentration decreases, while both ozone generation rate and ozone generation efficiency increase at first, reaching peak value, then decrease; When power supply frequency is changed in the range from 5.0kHz to 9.9kHz, no apparent laws of ozone concentration, generation rate and generation efficiency are found; When gap spacing is changed in the range from 0.3mm to 0.5mm and dielectric thickness is unchanged, shorter gap doesn’t show better effect.