bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation and cell imaging of nitrogen-doped graphene quantum dot conjugated indomethacin
Authors: Feng Shixuan , Li Hongli , Pan Jiaqi , Li Chaorong , Zheng Yingying
Published: December 2019

The nitrogen-doped graphene quantum dot conjugated indomethacin (N-GQD-IDM) was synthesized by an amide reaction. The results of FTIR indicated that the synthesis of N-GQD-IDM was successful. It was then co-cultured with MCF-7 cells, and obvious fluorescence was observed under a laser confocal scanning microscope. With the increase of incubation time, the material accumulated significantly in the cells and the fluorescence intensity of the cells was slightly improved. This compound could be suggested as a promising fluorescent probe in cancer cell labeling.
Construction of CdS/Ni3S2 Heterojunctions for the Enhancement of Hydrogen Production
Authors: Li Hongli , Pan Jiaqi , Feng Shixuan , liu Xin , Li Chaorong
Published: December 2019

The CdS/Ni3S2 heterojunction is prepared by a two-step hydrothermal method. The structure and crystalline phase are proved by SEM, TEM and XRD. The photocatalytic hydrogen production performance of the CdS/Ni3S2 heterojunction exhibits about ∼24 times enhancement that of pure CdS. It may be ascribed to the CdS with narrow band gap could increase the solar utilization. What’s more, the Ni3S2 with quick photon-generated electrons transferring could improve the separation of photon-generated carriers.
Effects of Different Carbon Content on the Extraction of Silicon Aluminum Alloy By Carbon Reduction Fly Ash
Authors: Bai Zhiling , Qin Bingke
Published: December 2019

Effects of different carbon distribution on the extraction of silicon aluminium alloy by carbon reduction fly ash were studied. X-ray diffraction instrument was used to characterize phases of the products. The results showed that when the carbon content was 0.8 to 1.0 times that of carbon, alumina and silicon carbide were included in the reduction products. When the carbon content was 1.1 times that of carbon, the reduction products were Al, Al4.5FeSi, Si, SiC and FeSi2. When the carbon content was 1.2 times that of carbon, the reduction products were SiC, Si, Al and Al4.5FeSi. With the increase of the amount of carbon, the effect of preparing silicon aluminium by carbon reduction fly ash was better. In this experiment, when the carbon content was 1.2 times that of carbon, the carbon reduction fly ash had the best preparation effect on silicon aluminum alloy.
Microstructure and chemical composition analysis of a vortex steam flowmeter
Authors: Ren Facai , Wu Xinghua , Tang Xiaoying
Published: December 2019

The microstructure and chemical composition of a vortex steam flowmeter made of 304 austenitic stainless steel were investigated based on the optical microscope and scanning electron microscope analysis. The results show that the microstructures of flange and weld between the flange and main channel are austenite. The chemical composition analysis shows that the contents of Ni and Cr of flange and weld between the flange and main channel do not meet the relevent standard.
Creep deformation calculation method on sandstone rock foundation settlement of nuclear island
Authors: Qi Xiaohai , Fan Yibo , Bai Yanqiang , Li Jianguang
Published: December 2019

Most nuclear island built its foundation on the bed rock. Generally the bearing capacity of these bed rocks is very high and the settlements of these buildings are very small. But in some cases we should consider the nonlinear part of the bed rock deformation when the bedrock is sandstone, Siltstone and Shale ect. under the foundation. Because these Metamorphic deformations are mostly creep deformation. This article analyzed settlements of a nuclear island’s foundation which are much greater than it were being designed. The deformation of sandstone is very large when with high load on top of it. Long time of deformation can bring many problems in nuclear power plant, such as pipe tolerance, building connection problem, cable connection problem and can make damage of them. Compared observed dates and a calculation result by using FEM software. And here gives a simple calculation method on nuclear island foundation settlement on sandstone.
Development Status and Application of Polysilicate Flocculants
Authors: Chen Zhao , Ping Liu
Published: December 2019

Flocculation method plays an important role in water treatment. The quality of flocculation depends to a large extent on the performance of flocculant. As a new type of inorganic polymer flocculant, polysilicate flocculant has good effects in removing turbidity, removing algae, removing color and removing organic substance. This paper comprehensively introduces several polysilicic flocculants, analyzes their flocculation performance, development and application.
The Rheological Property Study on the Slurry of Unclassified Tailings Cemented for an Iron Mine
Authors: Xin Li , Lijie Guo , Wenyuan Xu
Published: December 2019

There is a large iron mine deposit in Anhui province, the mining and dressing ability was designed to 4.5 million t/a, the main mining method is stage open stoping with subsequent filling and the filling ability is 100m3/h. The experiment process of rheological property for the slurry of unclassified tailings cemented will be shown in this paper. By the experiments of diffusion degree and viscosity test for slurry with different concentration and sand-cement ratio were carried on, the relation between rheological property of the slurry and ratio parameters can be got. The experimental results effectively evaluate the rheological properties of the filling slurry; the ratio parameters of filling material which were accordant with the requirements of the mine filling process about the filling slurry pipeline can be provided.
Study on Distribution Law of Spontaneous Combustion “Three Zones” in Goaf of Fully Mechanized Mining Face with Large Mining Height
Authors: Li Chengyu , Zhang Lili
Published: December 2019

In order to explore the large mining height are broken coal seam fully mechanized working face goaf spontaneous combustion “three zones” under the different height of distribution, through the establishment of numerical model, builds the working face goaf spontaneous combustion “three zones” three-dimensional sampling analysis system, through the analysis of oxygen, carbon monoxide, carbon dioxide and other coal spontaneous combustion index gases change law of goaf spontaneous combustion dangerous area under different heights for the division, the goaf three-dimensional spontaneous combustion dangerous area is determined. The results show that the “spontaneous combustion zone” of goaf in fully mechanized coal face of large mining height gradually widens along the vertical height, and the spontaneous combustion risk area becomes larger.
The study on desiliconization mechanism of sodium aluminate solution prepared from aluminum ash
Authors: Wang Yiru , Zhao Qiupin , Li Xiaolong , Zhi Pengkuo , Zhao Dan
Published: December 2019

The sodium aluminate crude solution prepared by using aluminum ash often contains a certain amount of sodium silicate impurities, and needs refined desiliconization. In this paper, desilication treatment of sodium aluminate solution by adding calcium oxide during sintering and refining. Experimental results show that the amount of calcium oxide added, desiliconization time and desiliconization temperature have an important influence on desiliconization efficiency of sodium aluminate solution. The results show that the desiliconization efficiency can reach 95.80 % under the optimal conditions, which satisfies the crystal decomposition of sodium aluminate solution.
Low-nitrogen combustion reformation for boiler burner
Authors: Yang Yan , Zhang Junjie , Liu Xiaobin , Hongxia Li , Wang Hongtao
Published: December 2019

In view of the current reformation for denitrification and cost reduction in coal-fired power plants, the boiler burner was upgraded in our company. On the basis of the comprehensive study of the low nitrogen burners of the major coal-fired power plants, the following low nitrogen retrofit measures were implemented: low NOx retrofit measures of the burners, anti-slagging and anti-corrosion measures, as well as high-efficiency measures for stable combustion. The results showed that the improved burner had better air counterweight ratio and could ensure the stable combustion of pulverized coal. Under the pure coal condition, NOx was reduced from 600mg/m3 to 210mg/m3. Under the mixed combustion condition, NOx in the flue gas decreased from 410mg/m3 to 160mg/m3. The boiler efficiency was slightly improved after the reformation, for the boiler efficiency increased from 91.49% to 91.79% under the condition of gas mixing and increased from 92.92% to 93.79% under pure coal condition. As shown above, the NOx emission for burner was reduced without affecting the working efficiency and the cost of denitration was also controlled after reformation.
Research on Risk Assessment of Coalbed Methane Development Project Based on SEWM-GCA
Authors: Wang Wanqing , Lyu Shuran , Zhang Yudong , Shuqi Ma
Published: December 2019

Coalbed Methane development is a complex system project with complex technology, many links and long cycle. It is highly susceptible to risks such as legal, technical and management during the development process. In order to scientifically measure the overall risk of CBM development projects, reduce resource waste and property losses caused by risk management failure. This paper constructs a risk assessment index system for CBM development projects consisting of six first-level indicators and 28 second-level indicators. The weight of each indicator is calculated by the structural entropy weight method. Secondly, based on the grey clustering analysis method, the theoretical model of risk assessment for coalbed methane development projects is established. Finally, an empirical study on a coalbed methane development project in Qinshui County, Shanxi Province was carried out using the evaluation system. After calculation, the overall risk level of the project is Grade II. The evaluation results are consistent with the actual situation of the enterprise, indicating that the established evaluation system has certain effectiveness and feasibility.
Research on Comprehensive Efficiency Evaluation of Mineral Resources Development
Authors: Yi Lu
Published: December 2019

Based on the analysis of ecological economy and circular economy of mineral resources development, this study establishes a comprehensive efficiency evaluation index system from three aspects: resource utilization efficiency, ecological compensation efficiency and development benefit efficiency, and uses the entropy method to determine the index weight. The comprehensive efficiency levels are evaluated by the TOPSIS analysis method. Through the empirical research, the sample enterprises have been comprehensively evaluated. The evaluation results show the reliability and practicability of the evaluation indicators and evaluation methods, and provide reference for the future high-quality development of the enterprise.
Vertical axis wind turbine with low turbulence Fluid-driven simulation
Authors: Zhou Ping , Yang CAO , Jiawei QI , Jinyi LI
Published: December 2019

New blade was designed by combining the advantage of sweepback and characteristic of flight trajectory. Mass and rotational inertia of turbine were calculated before using UDF and SDOF to build up the condition of fluid-driven simulation and observing the behavior of VAWT with airfoil NACA0012-800, LJY-800 and NACA23012-800. Results showed the potential of new designed airfoil and blade with better aerodynamic stability. Fluid-driven simulation gave out further suggestion that VAWT with high lift-drag ratio coefficient and power coefficient should be validated for its feasibility by fluid-driven simulation.
Research on Control Factors of Remaining Oil Distribution
Authors: Wei Xiaolong , Hu Wenjun , Li Tao , Yuan Yaofeng
Published: December 2019

Aiming at the characteristics of the overall dispersion and local enrichment of residual oil in the high water cut period of the continental water flooding reservoir, the Fuyang oil layer in the V block of Xinli Oilfield is taken as the research object, the remaining oil enrichment law is the main line, and the comprehensive application of earthquake, logging. Based on drilling, logging, closed coring, testing and production dynamic data, we conducted research on the effects of various geological factors and development factors on the remaining oil distribution. Preliminary research indicates that the remaining recoverable reserves with a certain scale are mainly controlled by the heterogeneity of reservoirs such as low-order faults, interlayers and physical properties, and the differences in hydrodynamic conditions.
Energy, environmental and economic assessment of a manufacturing plant with practical solutions
Authors: Wang Chunping , David Chicaiza Ortiz Cristhian
Published: December 2019

Considering the role that China has in the industry which triggers challenges in the environmental, economic and energetic sector. This study aimed to evaluate the energy consumption key points for a manufacturing factory located in Shanghai and propose practical projects to improve its performance. The methodology followed an inventory analysis and theoretical calculation in the three sectors mentioned, being the most representative the emissions of carbon dioxide, payback period and the standardization of the energy units. Among the results, the most energy-consuming areas and equipment were found; then, three projects were suggested to implement: the installation of a heat recovery system for the air compressor system, an insulation layer for the injection machine and installing a new air compressor, plus several common suggestions for manufacturing plants. Most of the projects presented a payback period lower than two years and relatively fast implementation for manufacturing plants.
Research on International Comparison and Future Development Trend of China’s Electrification Level
Authors: Zhang Chuncheng , Li Jiangtao , Weng Yuyan
Published: December 2019

Problems such as shortage of resources, environmental pollution, and climate change are increasingly becoming serious obstacles to the development of human society. To cope with these problems, a new round of energy transformation is in full swing, and electricity is playing an increasingly important role as a clean, efficient and convenient secondary energy source. In this paper, we compare China’s electrification level with the global and 10 typical countries, summarize the development characteristics of global electrification level, analyze the current situation of China’s electrification level. In the end, we comprehensively consider the factors affecting the electrification process, and combine relevant research to judge the development trend of China’s electrification process in the future.
Preparation of Calcium Chloride Composite Adsorbents for Woodchip by Carbonization Porosity
Authors: Hu Bing , Shao Youyuan
Published: December 2019

In order to improve the mass transfer performance of calcium chloride based composite adsorbents, calcium chloride was embedded in wood chips by soaking, and then the calcium chloride wood chips were carbonized to form holes. SEM images and elemental analysis show that at a charring temperature of 700 °C, the composite adsorbent prepared by charring calcium chloride sawdust has a developed pore structure, and calcium chloride is evenly dispersed in the adsorbent. The adsorption properties of the composite adsorbent to ammonia gas were shown to be 0.204, 0.253 and 0.285 kg/kg at evaporation temperature of - 5 °C and condensation temperature of 40 °C at adsorption time of 5, 10 and 15 min, respectively. SCP(refrigeration power per unit mass sorbent) is 868.96, 540.02 and 405.16 W/kg, respectively, with average adsorption rates of 6.79 * 10-4, 4.22 * 10-4 and 3.17 * 10-4 kg/kg/s, respectively, At the same time, the expansion and agglomeration of calcium chloride were solved.
Sound insulation and noise reduction technology for modular housing used in airport environments
Authors: Qiu Jialin , Zhang Jianfei , Zhang Qingyu , Chen Baoguang , Zhang Pingping , Xie Rongling , Li Minghui
Published: December 2019

The purpose of this study is to provide a modular building of steel structure to meet the requirements of internal construction and acoustics of the airport, improve the living environment and rest conditions of tower staff, relieve the daily work pressure of staff and improve work efficiency. The research of this subject has practical application value for the construction of staff dormitory of airport tower.
Experimental investigation of high strength reinforced concrete columns damaged by fire and retrofitted with CFRP jackets
Authors: Xu J , Tan C , Aboutaha R
Published: December 2019

This paper presents the compressive behaviour of high strength circular reinforced concrete (RC) columns exposed to fire following the ISO834 standard fire curve for 1 or 2 hours, air cooled, and then retrofitted with 2 layers of transverse carbon fibre reinforced polymer (CFRP) wraps. Total 5 circular RC columns ϕ300mm x 1000mm) were tested to investigate the effects of fire duration and the effectiveness of CFRP jackets. The investigated compressive behaviour of columns included load-displacement relationship, CFRP load-strain response and failure mode. Large temperature gradient was observed when columns were exposed to fire. For the unretrofitted columns, the test results showed that the ultimate capacity and stiffness of fire-damaged RC columns was decreased due to the deterioration of concrete at elevated temperatures. Longer fire duration leads to more sever damaged on columns. CFRP jackets could effectively restore the stiffness and improve the ultimate capacity of fire-damaged circular columns.
Research on Curriculum Reform of Mechanical Manufacturing Equipment Design Based on Engineering Awareness Training
Authors: BaoJiading  , Weiguang Zheng
Published: December 2019

Machinery Manufacturing Equipment Designis an important professional course in mechanical design, manufacturing and automation of colleges and universities. It involves a wide range of knowledge, and requires a high level of students’ comprehensive ability to apply knowledge. It is practical and applicable. However, the current teaching model still has a weak engineering awareness, and students lack engineering practice ability and independent innovation ability. The study of many contents of the course still stays in the teaching of theoretical knowledge, so that the students’ understanding of the course Mechanical Manufacturing Equipment Designis limited to the text of the book and cannot be combined with engineering practice. Therefore, the teaching content of the course Machinery Manufacturing Equipment Designneeds to be reformed, mainly to strengthen students’ engineering awareness, thus strengthening students’ practical ability and innovative ability, and promoting students’ all-round development.
Research on Teaching Reform of Experimental Measurement of Temperature Field and Thermal Deformation of Machine tool
Authors: He Shuilong , Tang Tao , Bao Jiading , Tang Rongjiang
Published: December 2019

With innovation and reform proposal of intelligent manufacturing 2025 in China, the precision of machine tool is required to be higher in the field of intelligent manufacturing, and the thermal deformation of machine tools is one of the main factors affecting machining accuracy. The measurement of temperature field and thermal deformation of machine tool has become one of the most important contents in undergraduate teaching experiments in many colleges and universities. In view of the shortcomings of the traditional teaching of the experiment, which only uses some instruments for finite point measurement, an experimental teaching scheme is supplemented by vibration for full-state testing, along with a new testing technology is proposed in this paper. All of them are expected to enrich testing means, expand the students’ horizons, improve students’ ability of testing, data processing and analysis, increase students’ interest in learning, and enhance students’ comprehensive design ability of machine tool fixture. The practice shows that the experimental teaching plays a positive role in cultivating students’ knowledge mastery ability and using theoretical knowledge to solve problems, thus greatly improve the teaching effect.
The effect on the shock wave resulting from the rocket explosion on launch pad
Authors: Wang Yan , Wang Hua , Cui Cunyan
Published: December 2019

Once an explosion occurs, it would threaten the safety of personnel and facilities around the launch site. In order to study the propagation law of shock wave near-ground and the multiplicative effect on peak overpressure of the ground, the finite model of near-surface explosion has been established based on explicit nonlinear dynamic ANSYS/LS-DYNA program. Results show that the existence of the ground will change the propagation law and conform to the reflection law of the shock wave. For gauges at different heights, ground may have different effects on the peak overpressure. When xis not greater than 20m, the peak overpressures of h greater than 2m are the same, but less than the peak overpressures of hequal to 2m. When x is greater than 20m, the peak overpressure decreases with the increase of h, and eventually the peak overpressure of different h gradually tends to be the same.
Research on the control technology of heavy layer hard roof blasting
Authors: Wang Jianwei
Published: December 2019

In this paper, based on the typical geological features of heavey layer hard roof, around a blasting weakening control of complete sets of technology, through the theoretical calculation and numerical simulatio, analyses the rules of the thick layer of hard roof and the characteristic of mine pressure appear; Based on the theoretical analysis, the attenuation height of vertical blasting and the circular blasting distance are determined. By weakening roof blasting scheme design, pull cut blasting with two lane ahead of deep hole blasting weakening technology, this paper introduces hole arrangement, drilling tool, design parameters control and instrument. A complete set of technical measures to reduce the control of hard roof blasting in thick layer is formed, and the rationality of the technical measures is confirmed by field observation. The relevant research results have important practical significance and reference value to the hard roof management of similar geological conditions.
Degradation of phenol in water by Fe(II)-citrate activated persulfate oxidation
Authors: Fang Maoying , Mao Mengqian , Wen Zhiguo
Published: December 2019

To enhance the degradation efficiency, complexing agent citric acid (CA) and trisodium citrate (TC) were introduced into the Fe(II)-persulfate (Fe2+/PS) oxidation system to degrade phenol. And the optimal operating conditions were determined. The results showed that Fe2+-citrate/PS system had higher degradation efficiency than the others. The optimal operating conditions to degrade phenol in water were: a PS concentration of 0.06 mol/L, a Fe2+ concentration of 0.02 mol/L and a TC concentration of 0.01 mol/L, while reaction temperature and the initial pH values had little influence on the phenol degradation.
Research on Project Approval Evaluation Index of Highway Engineering Metering Technical Specification Based on Delphi Method
Authors: Zhu Jing
Published: December 2019

As the standard and basis for metrology, testing and calibration, highway engineering metrological technical specifications play a key role in promoting highway metrology. It is an important part of the national metrological technical norms, and it is of great significance to evaluate it in the project approval process. Based on the literature research and Delphi method, this paper aims to find out the project evaluation indicators of the highway engineering metrological technical specification project, and provide decision makers with a scientific evaluation method for reviewing projects.
Microstructure of P92 Steel for Main Steam Pipeline of Ultra Supercritical Units after 50,000 h Service
Authors: Xinmei Li , Zhang Zhongwen , Zou Yong , Baoshuai Du , Wei Yuzhong , Yin Zhiyi
Published: December 2019

The microstructure of P92 steel used in the main steam pipeline of ultra-supercritical unit after 50,000 h service was studied by means of metallographic microscope, scanning electron microscope, energy dispersive spectroscopy and X-ray diffraction. The results show that the microstructure of P92 steel is still lath martensite after 50,000 hours of service at high temperature, but the martensite recovers. There are many large-sized M23C6 and Laves phases in the structure, and the aging phenomenon is obvious. The compound of bismuth is small in size and difficult to grow during service, which is beneficial to the improvement of creep rupture strength of P92 steel. The initial particle size of M23C6 and Laves phase is small, which is beneficial to improve the high temperature strength of the material. With the extension of service time, the size of M23C6 and Laves phase increases, which promotes the creep cavity and reduces the creep rupture strength of the material.
Research on Finite Element Simulation of Typical Down Lead of Transformer Substation
Authors: Xiubao Pan , Peng Li , Bin Liu , Jingchao Wang , Yongkun Zhu , Danyu Li
Published: December 2019

To calculate the stress status of equipment terminal exactly, this paper establishes the overall simulation models of two types of down lead structure systems, and compares them with the test result. The result shows that for cross line - down lead model and truss - down lead model, a relatively good effect has been obtained for both of them by using cable element to simulate conductor, and the error between the terminal stress simulation result and the test result is controlled within 15%, which means that the finite element simulation model of this paper is exact and reasonable.
Determination of ground motion parameters by seismic response analysis method of soil layer
Authors: Zhou Chang Xian , Zheng ShaoPeng , Ye YouQuan , Hao  , Wang Ping Fu
Published: December 2019

In this paper, the factors affecting the results of seismic response analysis of soil layers are analyzed by substituting trial calculation for various factors in the engineering example of seismic safety evaluation. In the soil response analysis of building site, the lithology of overburden soil, the sudden change of soil structure (interlayer) and the input shear wave value all have influence on the soil seismic response. Among them, the weak interlayer has significant influence on the peak acceleration and characteristic periodic value of seismic response analysis, while the hard interlayer, simple overburden and the type of bedrock soil have little influence on the seismic response of soil. The following construction projects must be evaluated for seismic safety:(1) Major State construction projects; (2) Construction projects that may cause floods, fires, explosions, massive leakage of highly toxic or highly corrosive substances or other serious secondary disasters after being damaged by earthquakes, including reservoir dams, dikes, oil and gas storage, and storage of inflammable, explosive, highly toxic or highly corrosive substances. Facilities and other construction projects that may cause serious secondary disasters; (3) nuclear power plants and facilities that may cause radioactive pollution after earthquake damage; (4) other construction projects that provinces, autonomous regions and municipalities directly under the Central Government consider to be of great value or have significant impact on their respective administrative regions.
Monitoring Instantaneous Dynamic Deformation of A High-rise Building by Digital Photography
Authors: Liyuan Wu , Liu Xiaodong , Chen Mingzhi , Chengxin Yu
Published: December 2019

In order to make up for the shortcomings of conventional measurement methods in measuring instantaneous deformation of High-rise buildings, in this paper, we propose the method of IS-PPT(Image sequence-photographic proportional transformation)method based on digital photogrammetry to monitor the instantaneous Dynamic deformation information of High-rise building. The specific actions of this method are: Setting up the camera in the right position to make the monitoring object in the center of the image and Setting five stable reference points in the vertical direction of the objective lens at the same time, then selecting feature points as Monitoring points on High-rise building. According to the method of IS-PPT, the pixel variation of the monitoring point on the image plane is transformed into the actual amount of change in-object plane, thus, the actual instantaneous deformation value of High-rise building and its regulation of variation with time are obtained. This method can warn potential dangers in real time and provide data support for maintenance of high-rise buildings timely.
Study on mechanical properties of the gravelly soils with consolidated-undrained conditions
Authors: Luo Fei , Wei Song , Xu Zihan , Jing Li
Published: December 2019

A standard stress path triaxial test system (STDTTS) was applied to study the mechanical properties of gravelly soil at initial relative densities of 0.13,0.5K 0.67 and 0.81 under confining pressures of 50,100,200 and 400 KPa, respectively. The results in the consolidated undrained tests show that all stress-strain curves behalf strain softening. With an increase of confining pressures, the pore pressure increases gradually and is almost irrelevant to initial relative density. With the increase of initial relative density, the peak strength of tested samples shows an uptrend, and its strength conforms to the Mohr-Coulomb strength criterion.
Prediction of ground settlement on shielded water-rich sand layer considering groundwater level and tunnel depth
Authors: Bo Wu , Jie Xu , Wei Huang , Zhigang Li
Published: December 2019

In order to research the effect of different groundwater level and tunnel depth on the ground settlement law for the shield construction of the water-rich sand layer, monitoring data of Fuzhou Metro Line 6 project is adopted and analyzed. The finite element software Plaxis 3D is used to carry out the numerical simulation of the project. Using the “activate” and “deactivate” functions of Plaxis 3D finite element software, the jack thrust, grouting pressure, face pressure, shield machine advancement and splicing of the segment are simulated. The calculation results in terms of vertical displacement of ground surface are in good agreement with the actual monitoring data. Using this numerical simulation method, under the combined action of different groundwater level and different tunnel depth, the ground settlement law of shield in the water-rich sand layer is studied, and the following conclusions are drawn: the shallower the groundwater level in the same tunnel burial depth The greater the surface settlement, the greater the buried depth of the tunnel and the smaller the surface settlement.
Dead-time Compensation Method Based on Field Oriented Control Strategy
Authors: Miao Zichao , Wei Jiangfeng , Guo Tingting , Zheng Mingyue
Published: December 2019

This paper analyzed a dead-time effect and zero-current clamping phenomenon in FOC control strategy, and then proposed corresponding compensation measures. The Field Oriented Control (FOC) strategy of brushless motor is improved according to this Dead-time Compensation measure. On the basis of the existing FOC control theory, a dead-time hysteresis loop is added near the current zero-crossing point to prevent current fluctuation and zero-point clamping from causing errors. The dead-time compensation is carried out in each PWM cycle according to the principle that the actual volt-second area is equal. Finally, the feasibility of the method was verified by experiments, the results showed that the compensation method effectively improves the current waveform and improves the stability of the motor operation, and it proved to be of good use value.
Study on deformation law of slope foundation under different external loads
Authors: Wang Yuan
Published: December 2019

The external load has a great influence on the stability of the transmission tower foundation. Considering that the external load on the foundation is more complicated, the external load is simplified to the basic center. The analysis of the deformation law under the external load is helpful to grasp the dangerous part of the foundation after being subjected to external force. In order to highlight the variability in the direction of the external load, the external load is set to a certain size, and the load direction is regularly changed. Using the finite element difference software FLAC3D to analyze the internal deformation law of the model under nine working conditions. The results show that the deformation of the foundation in the horizontal and vertical directions will change regularly with the direction of the concentrated force. When the direction of the concentrated force is within a certain range, it will play a positive role in the stability of the foundation.
Research on pavement quality control based on bayes’ theorem
Authors: Bei LIU , Tongxing CAI , Sheng XIAO , Hang YUAN , Qiang Wang
Published: December 2019

In order to meet the fine construction requirements of municipal engineering, improve the pavement stone paving technology level. Through the statistics of municipal engineering sidewalk construction common technical quality problems. Established the pavement surfacing technology quality control index system, and establish the quality control of causal relationship between spatial topology relationship structure model, using the mature of bayes’ theorem to the pavement stone pavement quality control study, forecast the quality of each control factor to influence the quality of the pavement stone pavement, the size of the causal backstepping method is used to analyze mechanism of quality control factor, finally, complete quality control evaluation by mutual information theory, find out the biggest quality control factor. Taking the project of yanjiang avenue (minsheng road to qingchuan bridge) in wuhan as an example, this paper applies bayes’ theorem and mutual information theory to the research of municipal pavement quality control. The results show that the probability of stone pavement quality accidents in this project is 2.83%, the roadbed quality control is not in place is the largest quality control factor affecting the fine construction of this project.
Dynamic Control Method of Thermal Power Units Compensating for Wind Power Disturbance
Authors: Li Jun , Wang Ting , Meng XiangRong , Li Jie , Gao Song , Lin Bo
Published: December 2019

The randomness and volatility of wind power generation are the main reasons restricting the capacity of power grid to absorb wind power. Thermal power units are the main force of power grid frequency modulation. The speed of load adjustment rate determines their response ability to power grid load. Based on the analysis of the characteristics of wind power generation, the nonlinear multiscale decomposition of the automatic power generation control (AGC) load command is carried out. Combined with the different load regulation rates of different types of units, the rational allocation of unit combinations can effectively ensure the power grid load regulation capacity and compensate the random disturbance of wind power.
Composition and Reproduction of Regional Landscape Elements of Highway
Authors: Huang Wenhong , Shao Shegang , Wang Jian , Yuan Minmin
Published: December 2019

In recent years, with the enhancement of people’s awareness of ecological environmental protection and aesthetic ability, as well as the requirement of sustainable development, the coordination between highway and landscape has gradually attracted people’s attention. How to reduce the damage of highway construction to the original landscape and create a harmonious road environment, and how to make highway construction not only meet people’s travel needs, but also coordinate with the surrounding environment, are new problems faced by highway construction. By sorting out the inheritance paths, this paper classifies the highway landscape, pays attention to the protection and grasps its essence, so as to protect the regional context and characteristics on the basis of combining the innovation of the times in the planning and construction of the highway landscape.
Auto-encoder based fault early warning model for primary fan of power plant
Authors: Lu Kuan , Gao Song , Sun Wenxue , Jiang Zhe , Meng Xiangrong , Zhai Yong , Han Yingkun , Sun Mengmeng
Published: December 2019

Primary fan system plays an important role in the operation of a power plant. However, due to the complicated working conditions of the primary fan and the strong coupling characteristics of multi-state variables, it is necessary to carry out feature engineering before using multivariate state estimation technique (MSET). In addition, no-linear operator should be designed to make sure matrix being invertible. This paper proposes an Auto-encoder based model to automatically construct a normal state memory matrix through unsupervised learning of neural networks. It reduces human intervention as well as the difficulty in giving a suitable non-linear operator design. This model is applied to the early warning of primary fan failure in a power plant in eastern Shandong Province.
Development and Application of Universal Hanging line Fixtures for 66-220kV Pointed cross-head
Authors: Jun Ma , Yonggang Shi , Gang Dong , Fuxing Gong , Kegang Wei , Xin Su , Yu Ding , Zhu Wang
Published: December 2019

For traditional fixtures, replace insulator string conductors as horizontal side hanging points in the linear pole tower of the transmission line. Its versatility is not strong, when using the wire rod and soft slings or carriages can not be shared and other limitations. The development of a Universal Hanging line Fixtures for 66-220kV Pointed cross-head is proposed. First of all, the fixtures span can be adjusted by adjusting the bolts, so as to better avoid all kinds of cross-burden head bolts, and cross on the joint plate and the cross-load bolt. Makes it stable. Secondly, fitting the wire rod directly in the slot at the hanging points at both ends of the mount and lifting with a wire rod depends on the needs of the lifting wire. You can also install a pin rod in the trailer, the carriage set or tight-line soft sling hanging on the pin rod, with the carriage or soft sling lifting. Solved the problem when replacing the insulator with pointed cross-heads, the generality of the wire lifting is not good. And the wire rod and carriage set and soft sling between the lifting tool interchange.
Application of Dry-coupling Ultrasonic Technology in Oil-level Detection of Oil-filled Equipment in Power Grid
Authors: Qinqin Liang , Chaofu Lin , Longfei Zhang
Published: December 2019

Dry-coupling ultrasonic technology is applied to detecting oil-level of oil-filled equipment in power grid. Vinyl silicone rubber is used to substitute liquid coupling agent to fabricate dry-coupling ultrasonic probe, which makes the ultrasonic directly enter the oil-filled equipment through the special structure of dry-coupling probe and detect oil-level of oil-filled equipment accurately and rapidly. Omitting the step that smearing liquid coupling agent on the probe can avoid the contamination on the surface of equipment and significantly improve the detection efficiency.
Research on the Relationship between Structural Change and Economic Growth in Guangzhou——An Empirical Analysis Based on VAR Model
Authors: Zhong Jiayi , Tang Jie , Zhong Jiayi
Published: December 2019

High-quality development is an active choice for socialism with Chinese characteristics to enter a new era. As one of the four first-tier cities, Guangzhou should set an example in promoting high-quality economic development. Based on the structural factors of economic development, this paper uses vector autoregressive model (VAR) to empirically analyze the dynamic relationship between consumption structure, industrial structure, ownership structure change and economic growth in Guangzhou from 1985 to 2017. The results show that there is a two-way Granger causality between Guangzhou’s consumption structure, industrial structure, ownership structure and economic growth. The two-way causal relationship between industrial structure change and economic growth is the most significant. From the results of variance decomposition, the consumption structure changes have the highest contribution to the trend of economic growth fluctuations.
Effect of acid wet deposition on operation of power grid equipment in China
Authors: Chao Yafeng , Zhang Liu , Huang Fuyong , Wang Cheng , Yue Yishi , Duan Jianjia , Liu Sanwei
Published: December 2019

The distribution law of acid rain in China is counted, and the operation of power grid equipment in acid wet deposition area is investigated. It is found that southern China has the strongest acidity of precipitation in the country. The ratio of SO4
2-, N03
-, NH4+, Ca2+ concentration in acid rain is higher. Acid rain causes serious corrosion of transmission line and transformation equipment in Shandong, Sichuan, Shanxi and Henan provinces of China. The acid rain and corrosion products aggravate the dissolution and chemical reaction of the original dry deposition pollution on the external insulation surface of power grid, which may lead to corrosive flashover.
Analysis and countermeasures of the tilt of lightning rod in transformer substation
Authors: Li Wenbo , Liu Lanlan , Sun Lipeng , Hu Jiarui , Wang Jun , Xie Yi
Published: December 2019

The lightning rod is an important lightning protection facility in transformer substations, which has a good protective effect for the compact equipment, while its safety performance is often neglected. The lightning rod in the 220kV transformer substation is up to tens of meters, the collapse of the lightning rod results in not only serious damage to the equipment, but also severe power failure. In this paper, the causes of the tilt of the lightning rod were analysed, and the installation requirements for the new lightning rod was proposed, which could effectively ensure the safety of the lightning rod.
Multi-factor Comprehensive Evaluation on Durability of Various Grouting Materials
Authors: Xia Junwu , Wang Tonglei , Yang Yuanzheng , Linli Yu
Published: December 2019

With In this paper, four grouting materials, namely new type grouting material, pure cement, cement-sodium silicate and glue sand, were tested by single factor for their water corrosion resistance, permeability resistance and volume stability. The durability of the four grouting materials under the environment of three factors was evaluated by the multi-factor fuzzy comprehensive evaluation method. The results show that the three kinds of new type grouting materials are better than the other three kinds of grouting materials in terms of anti-water corrosion and volume stability. In terms of impermeability, the performance of cement reached the best impermeability pressure of 0.8Mpa, but the impermeability pressure of new type grouting material with a water-cement ratio of 1.0 has also reached 0.6MPa, which can meet the impermeability requirement with a small gap with cement. As a scientific and effective evaluation method, the method will be helpful to the further study of the durability of grouting materials.
Extension of bridge cap beams with CFRP composites: experimental investigation
Authors: Tan Cheng , Xu Jia , Aboutaha Riyad
Published: December 2019

As rapid increase of traffic volume, bridge widening has been extensively conducted and studied. Compared to conventional method, such as costructing new bridge piers, extension of cap beam offers a more economical solution for limited amount of bridge widening. This paper presents and experimental investigation of extended pier cap beams reinforced with various Carbon fiber reiforced polymer (CFRP) systems. Four quarter-scaled hammer headed RC cap beams were cast and tested. Failure mode and load-displacement response were evaluated and reported. It was observed that the extened and CFRP reinforced beams exhibited good structural behavior in terms of ultimate strength, stifness and ductility.
Tin Oxide Nanofiber and 3D Sponge Structure by Blow Spinning
Authors: Wang Haolun , Huang Ya , Liao Suiyang , He Hongcai , Wu Hui
Published: December 2019

SnO2 nanofibers show wide applications in many advancing areas, such as gas sensors and semiconductors. The traditional methods of fabricating SnO2 nanofibers include electrospinning, hydrothermal synthesis etc. In this work, SnO2 nanofibers were prepared by blow spinning, which is a convenient and high-efficient method. Meanwhile, a 3D sponge nanofiber network can be produced by accumulating fibers in a novel collector. While traditional SnO2 nanofibers obtained from previous work show high brittleness, the SnO2 nanofiber sponge has good resilience against external compression and can recover to its original shape.
Synthesis and rheological properties of retarding polycarboxylate superplasticizers
Authors: Lai Huazhen , Fang Yunhui , Shao Youzhe , Lai Guangxing
Published: December 2019

In this paper, different types of retarding polycarboxylate superplasticizers (PT-1, PT-2 and PT-3) were synthesized. The structure information and functional groups of the water reducing agent were characterized by gel chromatography and infrared spectroscopy. The rheological properties of the retarding polycarboxylate superplasticizers for cement paste were studied. The results show that PT-1 containing sulfonic group and hydroxyethyl ester has good initial dispersion, while PT-2 containing hydroxyethyl ester and hydroxypropyl ester has long-term slump-retaining effect. The shear stress of PT-1, PT-2 and PT-3 on cement paste increases with the increase of shear rate, while the apparent viscosity decreases rapidly at first and then tends to be stable gradually with the increase of shear rate. The research results are of great guiding significance for the design of different types of retarding polycarboxylate superplasticizers.
Study on the Effect of Water Reducing Agent on Dolomite-based Magnesium Sulfate Cement
Authors: Zhou Jiaqi , Wu Chengyou , Miao Meng , Zong Jinping , Chen Yuanji
Published: December 2019

Adding different types and amounts of water reducing agent to Dolomite-based magnesium sulfate cement (DBMSC), and analysing the effect of water reducing agent on DBMSC by studying its setting time, water reduction effect and mechanical strength. on the one hand, Experimental results show that adding water reducing agent to DBMSC has a retarding effect on dolomitic magnesium sulfate cement, and reduces the hydration heat of cement; on the other hand, the water reduction effect of the water reducing agent on DBMSC prepared by light burning dolomite is not too obvious, and even the mechanical strength of DBMSC is lowered.
Effect of Different Additives Addition on Basic Magnesium Sulfate Cement Composite Sheet
Authors: Miao Meng , Wu Chengyou , Xing Sainan , Zhou Jiaqi , Zong Jingping
Published: December 2019

Study the effects of different admixtures and different dosages on Basic Magnesium Sulfate Cement (BMS) composite sheets, the effects of sodium citrate and phosphoric acid on the flexural strength and compressive strength of basic magnesium sulfate cement sheets were studied, XRD and SEM were used to analyze the composition and microstructure of hydration products. The results show, the addition of admixtures has a great influence on the properties of composite sheets. Adding the corresponding proportion of admixture to the plate, the mechanical properties are significantly improved. Therefore, the properties of sheet metal can be greatly improved by choosing appropriate additives.