bluuebunny/crossref_metadata_2025 huggingface dataset:
PML absorbing boundary condition for structure-preserving seismic wave modeling
Authors: Zhu Tong , Wang Yu , Sun Zhentao
Published: September 2020

Some efficient structure preserving algorithms have been proposed for high precision seismic exploration and detection in recent years. However, feasible artificial boundary conditions to truncate unbounded medium are never discussed in structure preserving seismic modeling. We pay our emphasis on application of perfectly matched layer absorbing boundary condition (PML ABC) to fit the structure preserving algorithms. In the domain of interest, a typical structure preserving algorithm is presented to discretize the conservative dynamic system, while in the PML region, traditional central difference is applied to solve the dissipative system. In the adjacent region of the interior and exterior domains, the temporary values of wave field between two time steps are approximated by interpolation using the present and the updated value of the wave fields in the PML region. A numerical experiment is adopted to demonstrate compatibility of the algorithms and no visible reflections of outgoing waves occur on the edge of interior domain.
Observing Dynamic Deformation of Masonry Wall in Vibration through Digital Photography and Kalman Filter
Authors: Liu Xiaodong , Tang Wei , Zhang Guojian , Yu Chengxin
Published: September 2020

Masonry structure is one of the common engineering structures, they encounter brittle fractures and even collapse in earthquakes, posing a major threat to the safety of human beings and property. This drives a need to monitor their dynamic deformation during earthquakes and study the seismic performance of masonry structure. This paper uses digital photography to monitor dynamic deformation of masonry structure in vibration. Kalman filter is used to eliminate the random noise and filter the change value of the pixel. Finally, the filtered value is converted into the actual displacement value by the time baseline parallax method. Results show that the relative measurement accuracy is 2.13‰ after using kalman filter to process deformation data. In the early vibration stage, masonry structure develops less deformation and it is in elastic state. The deformation of masonry structures increase gradually with the vibration being stronger. Digital photography can monitor the dynamic deformation of masonry structure in real time and grasp its health status. It can provide technical and data support for studying seismic performance of masonry structure.
The application research of a main machine hall for a thermal power plant with BRB
Authors: Xue Tao , Xing Guolei
Published: September 2020

As a kind of energy dissipation brace members by the yielding of metal, Buckling Restrained Brace (BRB) can overcome shortcomings of the common brace’s compression buckling, which has good energy dissipation capacity and ductility in earthquake. To study the Buckling Restrained Brace effect in the main machine hall, the nonlinear finite element analysis software ABAQUS is adopted to analyze the seismic performance of a main machine hall with BRB under the action of the rare earthquake and compare the elastic-plastic analysis results under the action of different seismic wave in this paper. The results show the structural seismic performance has been improved significantly, “no collapse under strong earthquake” can be achieved.
Study on Structural Improvement of Loess by Waxy Rice Powder in Weak Acid Environment
Authors: Tang Xiaowu , Yu Yue , Fei Minliang , Sun Guoping , Zhao Wenfang
Published: September 2020

Waxy rice is widely used in many ancient buildings due to their good performance in some fields (such as caking property, impermeability, weatherability, etc.). In the humid environment of South China, the excavation of ancient sites is faced with many problems, especially for sites with deep burial depth, it is necessary to set support and minimize the impact on the site environment. In the excavation project of Jingtoushan site, located in the town of Sanqi, Yuyao, Zhejiang Province, China, the loess between the steel structures supports needs to be reinforced. Waxy rice, as a traditional Chinese building additive, was used as the reinforcement of this project. Therefore, it is of great significance to explore the best proportion of waxy rice powder mixed with loess. In this paper, the standard columns with different proportion of waxy rice powder were made, and the uniaxial compression tests were carried out after curing for 0~180 days in standard humid environment (25°C and 60% humidity). It was found that the soil columns with 2% waxy rice powder had the best improvement effect. Due to the weak acidity of groundwater in South China, loess specimens mixed with 0%, 1%, 2%, 3% waxy rice powder was soaked in acetic acid solutions of 0mol/L, 0.5mol/L, 1mol/L and 2mol/L respectively, and the consolidation fast shear test, SEM test and mercury injection test were completed. The results show that the overall structure of the specimen is improved when the concentration of acetic acid is low. Acetic acid dissolves the calcium carbonate in the loess-waxy rice structure, quickly and effectively destroys the poor pore structure in the loess, and makes the waxy rice powder filled as the binder between the soil particles, forming a new structure. The improved structure has strong shear strength. When the concentration of acetic acid is high, the cementitious substance between the soil particles dissolves and the pore content increases. The waxy rice powder is not enough to fill the extra pores. Therefore, it is suggested that the proportion of waxy rice powder should be more than 2% in the areas with strong acidity. The study provides a useful reference for the excavation and follow-up protection of earthen sites in the acid environment of South China.
Experiment Study on the Compression Resilience of Loess
Authors: Xu Yali
Published: September 2020

Due to structure form of particles and the characteristics of loess, such as high strength and incomplete consolidation, in order to research the influence of structure on compression and resilience characteristics of loess, the compression resilience test for undisturbed soil and remoulded soil and compression resilience recompression test for undisturbed soil is carried out under five kinds of different water content. The results show that: the structure has great influence on the compression and resilience characteristics of loess, especially after or before the structure damage. And the structured yield stress is bigger, resilience characteristics is more and more strong. Moreover, when pre-consolidation pressure is ascertained, the structure must be considered. The research of compression and resilience characteristics of loess lays a foundation for proposing a new method of ascertaining pre-consolidation pressure.
Research on the Law of Stress and Strain Response of Surrounding Rock of Underground Powerhouse Cavity Excavated by Layered Cutting
Authors: Lin Xue , Gao Yang , Jiang Yanbo , Shi Zhenyue , Zhao Xinyue , Wu Kun , Zhang Jie , Yuan Cheng , Ge Xuze , Wang Qingbiao
Published: September 2020

As an important part of the construction of hydropower stations, underground powerhouses are increasingly perfected and synchronized with their construction methods. Layered cutting and excavation methods have emerged at the historic moment. This article takes Wendeng Pumped Storage Power Station as an example, using theoretical analysis, numerical simulation and other methods to study the influence of the layered cutting method on the change of stress and strain of surrounding rock, and draws the following conclusions: (1) The cave is from the first floor to the first during the eight-layer excavation, the tensile stress of the side walls on both sides is symmetrically distributed and there is a maximum on the same layer, and the compressive stress reaches the maximum at the bottom plate; with the increase in the number of excavation layers, the tensile stress on the side walls on both sides increases first and then decrease, the surrounding rock compression stress of the vault and floor continue to decrease. (2) During the excavation of the cavern, the strain of the vault on the same floor reaches the maximum value, and the strain continues to increase with the increase of the number of excavation layers. The excavation of the eighth floor has increased to 4.94mm; The strain changes less with the increase of the number of excavation layers, and is always maintained at 2.50~2.75mm; the floor strain decreases layer by layer. (3) By comparing the on-site monitoring and numerical calculation data, analyze the changing trend of the on-site measured arch strain and the side wall stress around 2.50mm up and down, and calculate the difference ratio between the numerical simulation and the measured data. The excavation time difference ratio reaches the maximum value of 29.1%, which verifies the correctness of the simulation experiment and provides a supporting scheme for the underground powerhouse in harmony with the deformation law.
Research on Application Model of Marine Geological Sampling Model Based on Object-Oriented Relational Mapping
Authors: Chen Chen , Sun Yuxi , Tan Jun
Published: September 2020

In the study of marine geology, the sampling technology and preservation are very important links. Marine geology is developed on the basis of marine sediment sampling technology. ORM (Object-Relation Mapping) technology is an effective method to solve the “impedance mismatch” between object model and relation model. The research on object-relation mapping technology has become a research hotspot in the field of software architecture. The development of object-relational database has enhanced the ability of database to support complex data types, making the integrated storage of spatial data, topological relations and attribute data a reality. This paper proposes a class hierarchy based on the technical framework of object-relational mapping, and explains all kinds of classes. The application of this framework can simplify the mapping mechanism on the premise of meeting the requirements of marine geological sampling, thus providing users with an object-oriented way to intuitively access the database.
Interaction and Research of Biological Organic Fertilizer on Agricultural Soil Geological Improvement Preparation
Authors: Yu Wujiang , Lou Jinyong , Song Chunyan
Published: September 2020

Based on the characteristics of bio-organic fertilizer material composition, the paper carried out an experimental study on the improvement of poor soil geology. Through the study of the geological background, stratigraphic characteristics and Quaternary characteristics of poor soil, and through petrification analysis, it was found that quartz in soil geology accounts for a large proportion, high silicate content, severe weathering, and insufficient fertility. At the same time, this article discusses the mechanism of bio-organic fertilizer to improve soil geology, and clarifies that the addition of sludge increases the content of soil geological organic matter, which is beneficial to increase the soil geological aggregate structure and humic acid content, and promote the optimization of geological ecosystem.
Effects of Soil Remediation Agents and Microbial Agents on Soil Enzyme Activities
Authors: Han Lin , Zhai Yuying
Published: September 2020

Soil remediation agents and microbial agents can improve crop yield and improve crop quality, and amaranth is rich in a variety of nutrients, many of the body needs vitamins, proteins and various minerals. Therefore, soil remediation agent and microbial agent were used to treat amaranth. The results are as follows: In the cultivation process of amaranth, if the soil remediation agent is applied, the applied concentration should be 2 g·L−1; If the application of microbial agent, the application of concentration should be 1 g·L−1.
Application of Carbon Isotopes in Loess-paleosol Sequences in Paleoenvironmental Research
Authors: Hu Yi
Published: September 2020

Loess-paleosol sequences at the Chinese Loess Plateau have been proved the best-preserved carriers of paleoenvironmental information. Studies on carbon isotopes in loess-paleosol sequences could obtain useful information for paleobotany and paleoclimatology and reconstruction of paleoenvironment. This literature review points out some imperfections of previous studies and suggests that future studies regarding relationship between carbon isotopes and other climate factors, carbon isotopic fractionation during transformation of plant materials to soil organic matter under different ecological conditions, and carbon isotopes in modern soils of Chinese Loess Plateau should be given priority.
Design of Underground Displacement Measurement System Based on Mutual Inductance and Hall Effect
Authors: Wang Feng , Shentu Nanying , Li Qing , Wang Sheng
Published: September 2020

Deep displacement monitoring of rock and soil is important for landslide warning. By using mutual inductance effect and Hall Effect, the author designed the underground displacement sensing unit through the solenoid and permanent magnet and the Hall sensor. The author designed the Hall voltage measurement circuit and installation device, and used the mutual inductance voltage measurement circuit that the laboratory has realized, which can accurately collect the mutual inductance voltage and the Hall voltage in real time. Through the 485 communication, the collected data is transmitted to the upper computer, the mathematical model established by the curve fitting method can be used to measure the real-time displacement of the deep part of the rock and soil. The experimental result shows that the horizontal displacement measurement range is 0-40mm, and the measurement accuracy can reach 1.5mm. It can measure the underground displacement within a reasonable error range.
Method Verification of Soil Volatile Organic Compounds
Authors: Chen Tianqing , Wang Zhao
Published: September 2020

In this paper, purge-and-trap / gas chromatography-mass spectrometry is used to verify the analysis of six volatile organic compounds in soil, including 1,1-dichloropropene, benzene, and 1,2-dichloroethane. The feasibility of purge and trap / gas chromatography-mass spectrometry for the determination of VOCs in land Engineering was discussed. The results show that in the linear relationship, the response value and concentration of the volatile organic target object show a good linear relationship with a correlation coefficient of 0.9951 to 0.9996; the detection limit is 0.8 to 1.9 μg/kg and the quantification limit is 3.0 to 7.6 μg/kg. The relative standard deviation of 6 volatile organic compounds in precision is: 3.0% to 12.3%; the recovery rate of 6 volatile organic compounds in accuracy is: 112.4% to 127.0%. The verification results show that the linear relationship, detection limit, precision, and accuracy all meet the requirements of “Soil and Sediment-Determination of Volatile Organic Compounds Purge and Trap Gas Chromatography/Mass Spectrometry Method” (HJ605-2011). The purge-and-trap/gas chromatography-mass spectrometry technology can be used to achieve fast, accurate and sensitive detection of target substances, and can meet the detection requirements of trace volatile organic compounds, so it can be applied to environmental testing work such as soil.
Risk assessment model of underground engineering based on Delphi-AHP
Authors: Lei Xu
Published: September 2020

Underground engineering is an extremely complex system engineering, with many uncertain factors and extremely many and complex risk factors. In order to ensure the smooth completion of the organization and construction of the whole underground engineering, risk management is bound to be carried out, and in the process of risk management, risk analysis and assessment undoubtedly plays a crucial role. This paper on the study of underground engineering construction risk scholars both at home and abroad are reviewed, and then briefly summarizes of underground engineering risk analysis evaluation model at home and abroad, sum up experience, to establish universal underground engineering construction risk to risk factors to choose his own table, proposed a based on Delphi-AHP fast universal model of quantitative analysis for underground engineering construction risk to provide the basis for decision-makers quickly.
Analysis and Application of Isolation Layer of a School in Highly Fortified Area
Authors: Li Peng , Meng Zhaohu , Li Juhui , He Lu , Li Jianning , Li Yan , Wang Zhigang , Zhang Qinxiong , Han Guangzhao , Liu Tao , Yang Rong
Published: September 2020

A school complex building is located in an area with a seismic fortification of 8 degrees, with six floors above the ground and two floors below the ground, and has a frame structure. Using YJK calculation program and elastic time history analysis method, the calculation model is established. Through the comparison and verification of the isolated model with the isolated unit and the non-isolated model, the isolation scheme is determined, and the isolation scheme is determined through analysis and research. The isolation layer is arranged on the top of the basement column, and an isolation support is arranged on the bottom surface of each column of the isolation layer to separate the upper structure from the top of the basement column or the top of the beam so as to isolate the seismic energy and reduce the seismic action of the upper structure.
Field direct shear tests on a backfill soil slope and finite element analysis of its reinforcement schemes
Authors: Zhang Zhichao , Ye Longzhen , Chen Zhichao , Xu Shangrui
Published: September 2020

The field direct shear test was used to analyze the backfill soil strength of a filling slope, and the slope controlled by different reinforcement conditions was simulated by finite element method base on the shear strength by the field test. The results show that the shear strength parameters of the backfill soil are friction angle φ = 15° and cohesion c = 25 kPa. Reinforced by anti-slide pile with different lengths, the maximum horizontal displacement of the slope can be reduced by 79.7% ~ 81.3% compared with that of the unreinforced slope. The maximum shear strain of the soil is also reduced to some extent, and the sliding surface characteristics and the strain amplitude are weakened.
Field Test and Numerical Analysis of Flexible Retaining Wall of Shoulder Geocell
Authors: Pang Zhe
Published: September 2020

In order to study the stress and deformation characteristics of the shoulder type geocell flexible retaining wall, a three-dimensional numerical model of the geocell flexible retaining wall is established based on the reconstruction project of Zichang County urban transit section of Provincial Road 205 in Shaanxi Province, and the numerical calculation results are compared with the field monitoring results. The results show that the base pressure of the flexible retaining wall of the shoulder geocell increases with the increase of the filling height of the retaining wall, and decreases slightly after the completion of the construction; the horizontal earth pressure on each layer of the retaining wall is not evenly distributed, the horizontal earth pressure in the middle of the retaining wall > the horizontal earth pressure inside the retaining wall > the horizontal earth pressure outside the retaining wall; the horizontal earth pressure and the horizontal deformation after the stability are along the height of the retaining wall The drum distribution is the largest at the height H / 2 of the retaining wall.
Research on a Non-destructive Testing Technology for the Foundation of Transmission Tower Based on Rayleigh Wave Method
Authors: Wang Longlin , Wang Hua , Wu Changxia , Peng Xi
Published: September 2020

There are more and more accidents of transmission tower collapse caused by the defects of foundation. The safety of the foundation of transmission tower has gradually attracted the attention of relevant departments. However, for the existing concrete foundations of transmission towers, the conventional detection methods will not only cause structural secondary damage, but also have extremely low efficiency, which is not conducive to actual large-scale detection. Therefore, this paper aims to propose a non-destructive testing technology for the foundation of transmission tower based on Rayleigh wave method. The non-destructive testing theory for the foundation of transmission tower based on Rayleigh wave method was firstly introduced. And then the non-destructive testing procedure of the foundation size of transmission tower based on Rayleigh wave method was described in details. The proposed non-destructive testing technology for the foundation of transmission tower based on Rayleigh wave method was verified through an actual foundation model of transmission tower. The experimental results prove that the proposed method in this paper is feasible.
Research on structure and performance of polyurethane elastomer/superfine talcum powder composite
Authors: Ma Qixiang , Zhu Jingrong
Published: September 2020

The structure and performance of polyurethane elastomer/superfine talcum powder composites were investigated by X ray diffraction ( XRD), FTIR spectra and thermogravimetric analysis ( TG - DTA, DSC ). The results showed that talcum powder and polyurethane elastomer formed com pound structure of heterogeneous nucleation when the content of superfine talcum powder was right(such as 15% ), which caused the soft segments, hard segments and talcum powder of polyurethane elastomer to form interactional congeries system and the integrated mechanical properties and thermostability of polyurethane elastomer were improved.
Experimental Study on Humidity Structure and p-value of Undisturbed Loess in High-risk Slope
Authors: Jia Yajun , Tang Zhihong , Chen Cunli , Liu Naijun
Published: September 2020

A long-term dry-wet cycle will cause changes in the internal structure of the loess, which will affect its permeability coefficient and slope properties. In this paper, through the dry-wet cycle test, the changes of permeability coefficient P value, porosity and dry density of undisturbed loess and remodelled loess under the action of dry-wet cycle are studied. Under the condition of dry-wet cycle, the permeability coefficient of undisturbed loess in high-risk slope decreases, and the permeability coefficient of remoulded loess increases. Remoulding the original loess of high-risk slopes due to soil erosion is more likely to cause gullies and internal erosion, accelerating the occurrence of original loess landslides and collapse of high-risk slopes.
The risk assessment of tunnel surrounding rock deformation based on entropy weight method and extension matter element method
Authors: Hou Shoujiang
Published: September 2020

The deformation of surrounding rock is an expected geological hazard when the tunnel passes through the area with unfavorable geological conditions. If the surrounding rock deformation is too large, it will lead to serious safety hazards. In this paper, the entropy weight method is adopted to calculate the weight of each index. Based on the extension theory, the risk evaluation model of tunnel surrounding rock deformation is established. Five evaluation indexes, such as surrounding rock grade, tunnel depth, groundwater status, the uniaxial compressive strength of rock, and rock integrity, were selected to evaluate the deformation risk of surrounding rock in 10 sections of Sheta Village tunnel of Zhangjihuai high-speed railway. The results show that the surrounding rock deformation is high in 2 of the 10 cavities to be evaluated, and the workers must take reinforcement measures to strengthen the surrounding rock, which is of considerable significance to guide the scientific and reasonable construction of the tunnel.
Technical Specifications for Natural Grassland Improvement of Karst Area in Guizhou
Authors: Yang Xuedong , Li Li , Ding Leilei , Liu Jiajia , Liang Xianyi , Liu Jiming , Wang Puchang
Published: September 2020

In order to strengthen the protection of ecological environment in Guizhou, speed up the development of ecological animal husbandry, and improve the standardized production level of natural grassland in Guizhou, based on the summary of practical production and scientific research achievements, this paper stipulates the methods and measures of natural grassland improvement in Guizhou karst mountainous areas, as well as their application scope and operation steps. Specific requirements are put forward for forage sowing, field management and utilization of improved grassland in the process of natural grassland improvement. The formulation of this technical regulation has practical significance for scientifically guiding the standardization, standardized development and utilization of natural grassland in Guizhou karst mountainous areas.
Near-field directional seismic waves based on tunnel environment
Authors: Yue Yongao , Ren Dongxu , Chen Yongqian , Li Zhengfeng , Zhou Gaofeng , Cui Lujun , Han Chun
Published: September 2020

In this paper, a near-field directional seismic wave (NFDSW) method based on near-field application environment is proposed. Different from the far-field directional seismic wave technique, the time-delay parameter of near-field directional seismic wave is not a single fixed value, but a variation value. In this paper, the accurate delay parameters of target signal are estimated by cross-correlation method, then the phase axis of target signal is leveled by delay parameters, and finally the final target signal is obtained by array element superposition and inverse correction. Numerical simulation shows that the near field directional seismic wave technology can separate the target signal well and improve the quality of target signals significantly in the near field environment.
Stability analysis of the middle wall in process of double-arch tunnel construction
Authors: Gao Haidong , Li Gang , Guo Yanbing , Gao Peng
Published: September 2020

As the main bearing components of double-arch tunnels, the stability of the middle wall is related to the construction safety of double-arch tunnels during construction and operation. Different construction methods of double-arch tunnel have great influence on the stability of middle wall, especially when the excavation span is large and the buried depth is very shallow. Based on an ultra-shallowly buried double-arch tunnel with extra-large spans in Xiamen, China, the mechanical response and deformation law of the middle wall are obtained. Furthermore, the performance of the CRD method and the double-side-drift method for optimizing the deformation and stress state of the middle wall are compared. The results can serve as initial guidelines for the for the selection of double-arch tunnel construction schemes.
Application of BIM in Pipeline and Equipment Project of an Energy Centre
Authors: Zhao Yu , Zhao Na , Ma Jian , Ma Fan
Published: September 2020

This paper is based on BIM chemical plant upgrade project energy centre plant design, BIM Technology is applied to the project pipeline comprehensive design, using the Revit to complete the professional system modelling, using Naviswork to analyse the collision conflict between various disciplines and generate collision conflict report, through the pipeline comprehensive adjustment optimization model, improve the design quality.
Titanium-doped MoS2 monolayer as highly efficient catalyst for hydrogen evolution reaction
Authors: Shi Wenwu , Wang Zhiguo
Published: September 2020

The effects of Ti dopants on the catalytic activities of the hydrogen evolution reaction (HER) in monolayer MoS2 basal plane were investigated using density functional theory. Our study shows that Ti dopants that substituted Mo atoms in MoS2 have small formation energy, and the complex dopant structures involving multiple Ti sites are energetically more stable than the isolated ones. Doping Ti atoms greatly improves the catalytic performances of MoS2 with a near-ideal hydrogen-adsorption Gibbs free energy. Projected density of states analysis revealed that the mechanism for the improvement of catalytic activity is due to formation of the density of states near the Fermi energy level upon increasing dopant concentrations. It can be expected from the current results that excellent catalytic performance can be obtained by atomic composition modifications, such as Ti doping in the HER reaction.
Application of collaborative modelling method in Pile-Beam-Arc of Subway station
Authors: Luo Qingfei , Cao Quan , Li Wei , Zhao Chunsheng , Xue Qingwei , Zhang Mengheng , Shen Peng
Published: September 2020

Taking Pile-Beam-Arc of Harbin Metro Line 2 Shengzhengfu station as an example, through the Midas GTS NX, different methods are used to establish the numerical model of PBA method. The results show that the quality of the model generated by the collaborative modelling method is better and the modelling efficiency is higher. The specific embodiment is that the number of units generated by the collaborative modelling method is less than that of auto-solid method, and the operation time of the model is reduced. The quality of the model generated by the collaborative modelling method is better than that of auto-solid method, which improves the model convergence and accuracy. The efficiency and application conditions of collaborative modelling method are better than those of plane element expansion method.
Study on Intelligent Mine Based on the Application of 5G Wireless Communication System
Authors: Ma Long
Published: September 2020

In the traditional industrial sector, mining plays an important role. The development of a century-old industry is inseparable from the development and utilization of mineral resources. Mining is not only about the economy, but also about safety. In the past 100 years, dangerous mines have brought enormous challenges to the world’s industrial safety. Mine safety has always been a major concern of all countries in the world. People are constantly looking forward to and exploring, looking forward to safer, smarter, more automated, unmanned mining methods. With the rapid changes in the era of artificial intelligence and the era of all things connected, the new era of intelligent mines is really coming. Currently, 5G business is getting closer. Exploring and promoting 5G typical applications has become the key to successful 5G operations. With the acceleration of the commercialization of 5G technology, the application of 5G technology in the coal mining industry and the underground working face has achieved a seamless docking between the underground and the underground, which helps the operation of unmanned mining equipment and realizes unmanned mining. Fundamentally avoiding casualties has gradually become a reality. This paper starts with the concept of intelligent mine, summarizes the construction significance of intelligent mine construction and intelligent mine structure, and introduces in detail the application of 5G wireless communication system in intelligent mines. The 5G era is coming, it will bring huge changes to people’s lives.
Development and demonstration of CO2 flow numerical calibration system – part II
Authors: Xue Zhipeng , Liao Yonghao , Xu Junfeng
Published: September 2020

This project takes the flue at the tail of Fujian Kemen Power Generation Company as the research object. Calibration factor, precise flow value, etc. Through the above analysis, it is concluded that the ultrasonic flowmeter has high requirements on the location selection, and the measurement result is closer to the true value. The matrix type flowmeter is easy to arrange, and the location selection sensitivity is low; the single point pitot tube flowmeter has poor accuracy and is not recommended.
Research on Vitality Measurement of Village Public Space Based on Big Data and Multidimensional Module
Authors: Luo Jing
Published: September 2020

The study takes village public space as the object, builds an information database based on massive data, and builds a multi-dimensional module and measurement system for public space vitality measurement. The research introduces measurement indexes such as Syntactic geometry and integration degree, and establishes three sub-modules from different dimensions. For the three sub-modules and their constituent elements, element analysis, superposition calculation and correlation matrix are established. Through GIS-spatial syntactic analysis, reveal the element system that affects the vitality of village public space, explore quantitative analysis methods based on big data and multi-dimensional modules, and put forward scientific measurement methods and optimization suggestions.
Analysis of Biofilm-Resistance Factors in Singapore Drinking Water Distribution System
Authors: Li Yuanzhe , Wang Yilin , Xiao Peng , Narasimalu Srikanth , Dong ZhiLi
Published: September 2020

In drinking water distribution system (DWDS), biofilm offers protection of bacterial community within the extracellular polymeric substance (EPS) from outside stressors, including surrounding environment, predatory microorganisms and antibiotics. The growth of biofilm may increase cleaning and maintenance cost for the drinking water decontamination and expose high risk to human immune system. This article critically reviews current Singapore DWDS by analysing the leading and lagging performance of two stages, granulated active carbon (GAC) filtering and secondary disinfection by chloramine, which are highly relevant with the biofilm resistance. Furthermore, other extrinsic factors, such as pipe age and material, hydraulic retention time, seasonal change, primary ultraviolet disinfection, etc. are also reviewed. Finally, top-down approach to address the growth and biofilm resistance are proposed. Practices and technology methodology, e.g. good consumers’ hygiene, nutrient removal, chlorine disinfection, probiotic approach, anti-biofouling coatings are discussed with their associated challenges and opportunities.
Development and demonstration of CO2 flow numerical calibration system – part I
Authors: Xue Zhipeng , Liao Yonghao , Xu Junfeng
Published: September 2020

This project takes the flue at the tail of Fujian Kemen Power Generation Company as the research object. Due to the diversified forms of the tail flue, the installation position of the flow measurement equipment affects its flow calibration coefficient. Through the computational fluid dynamics method, a numerical simulation model is established to perform numerical calculation on the entire flue.
Preliminary study on the influence of residents’ central heating temperature on atmospheric environment
Authors: Zhang Xinyi
Published: September 2020

The cold weather in northern China requires a long heating period and uses central heating. The process of coal-fired heating has caused enormous pollution to the atmospheric environment. This paper starts from the point of reducing the central heating temperature of heating enterprises, and studies its impact on reducing pollutant emissions and mitigating air pollution. Think about whether it can alleviate the problem of air pollution in the northern winter by reducing the central heating temperature.
The Safe Storage Life Estimation for Energetic Materials
Authors: Gu Yan , Yang Huan , Yu Silong , Wang Fangfang , Liu Wenliang , Du Jiaojiao , Jia Lin , Zhang Dongmei
Published: September 2020

In the present study, the safe storage 1ife prediction of gun-propellant in different temperature mode were calculated by the dates of stabilizer content under thermal accelerated aging at temperature of 95°C, 90°C, 85°C, 75°C and 65 °C via Berthelot equation and Arrhenius equation. In order to demonstrate these predictions, all the estimation results have been compared with the real experimental results. Presented results indicate that the prediction via Arrhenius equation is consistent well with real storage experimental results at shallower reaction depth of stabilizer (α = 6.6%). Furthermore, predicting by shallower Berthelot equation is available at deeper reaction depth (α = 50%).
Research on Monitoring System Based on Crowd Sports Health and Regional Geological Environment
Authors: Yang Xudong , Man Xiaoni , Yu Tianbo
Published: September 2020

The paper proposes remote sensing on the monitoring of mine geological environment in important mining areas, the risk assessment of landslides in the mining area, the feasibility study of land reclamation in the mining area, the monitoring of tailing ponds and the safety assessment, etc. Monitoring and comprehensive evaluation methods provide new technical means for mine geological environment supervision, which can further strengthen the timeliness of mine geological environment supervision in China, and thus promote remote sensing technology to play a greater role in mine geological environment monitoring.
Research on the Development Status of biochar for Cr (VI) remediation Technology Based on Patent Analysis
Authors: Liu Miao
Published: September 2020

More and more chromium (Cr) is being discharged into the environment, which is posing ecological risks to animals, plants and microorganisms, and endangering human health. Hexavalent Cr (VI) was more toxic than trivalent Cr (III), and the mobility of Cr (VI) in the water environment was higher than that of Cr (III). Therefore, various effective methods of reducing Cr (VI) were developed. In this research, the “biochar”, “chromium remediation”, were taken as keywords for patent retrieval. The retrieval time is from 1986 to 2019. A great number of patents about Cr (VI) remediation and biochar are collected and analysed applying big data. Based on the number and the legal status of patent applications, and the trend of patent applications, the research situation of biochar for Cr (VI) remediation in China is studied by S-curve law which is used to describe the technology life cycle theory in TRIZ theory. The results show that the technology of biochar for Cr remediation is still in its initial stage and full of potential.
Desulfurization and Denitrification of Ship Exhaust Gas with Low Temperature Plasma
Authors: Chen Peng
Published: September 2020

In order to reduce the emission of pollutants such as sulfur oxides and nitrogen oxides in ship exhaust gas, the principles and experimental methods of desulfurization and denitrification with low temperature plasma with dielectric barrier discharge were introduced in this study. The impacts of reactor voltage and reactor frequency of low temperature plasma, humidity and oxygen content of ship exhaust gas on the efficacy of desulfurization and denitrification were also explored by experiments in this study. It was revealed that the low temperature plasma technology could desulfurize and denitrify the ship exhaust gas better. The efficacy of desulfurization and denitrification would be increased when the voltage increases. At a voltage of 20 kV, the removal rates of NO and SO2 reached 59% and 52% respectively. When the reactor voltage was maintained at 15 kV, the removal rates of NO and SO2 would rise at the beginning and decrease later with increase of the frequency. The highest removal rates of NO and SO2 were 55% and 42% respectively when the frequency was 10 kHz. The efficacy of desulfurization and denitrification can be affected by humidity and oxygen content of the ship exhaust gas. Researches in this study provided a crucial reference for the application of low temperature plasma technology in the desulfurization and denitrification of ship exhaust gas.
Experimental Study on Removal of SO3 from Flue Gas by Na2CO3
Authors: Xue Fangming , Su Jingcheng , Li Peipei , Zhang Yulong
Published: September 2020

The alkaline absorbent spraying technology is an efficient method for accurately removing SO3 in flue gas. By studying the characteristics of the technology, the reaction mechanism, the migration rule of SO3, and the experimental platform by using the real flue gas as the source of the alkaline absorbent jet removal of flue gas SO3. The results of the study show that the efficiency of the alkaline absorbent to remove SO3 is related to n(Na2CO3):n(SO3), flue gas temperature, residence time and other factors; under the test conditions, the flue gas temperature is 320°C, n(Na2CO3): n(SO3) is 1:4, the concentration of Na2CO3 solution after gasification is 52.6 mg/m3, and the concentration of soot is 4680 mg/m3 under standard conditions, which can ensure the removal efficiency of SO3 is above 85%; The effect of the catalyst is small and can be ignored. The above results can provide a reference for the domestic coal-fired power plants to carry out the research and application of alkaline absorbent to remove flue gas SO3 technology.
Research progress and ideas of Influence of hydrological regimes on river primary productivity of algae
Authors: Guo Weijie , Gong Dandan , Qiao Qianglong
Published: September 2020

The algae, as the primary producer of the water ecosystem, are the basic part of food chain in aquatic ecosystem. The flow pattern and hydrological process of the river have been significantly changed by the construction of the high dams. Not only the natural hydrological characteristics and physical and chemical conditions of the river were changed by the obstacle of the dams, but also the habitat environment on which the phytoplankton live, and its community structure, biomass and primary productivity of the water further were affected. In this paper, the research on the effect of river hydrological regime change on the primary productivity of water body were summarized and summarized. In the future, further research can be carried out in these aspects: (i) the analysis of the key factors affecting the primary productivity; (ii) clarifying the mechanism of the influence of hydrological situation change on the primary productivity and its distribution of algae in the reservoir area and downstream channel; (iii) establishing the coupling relationship between the change of hydrological regime and the primary productivity of phytoplankton.
Research on Low-Carbon Campus Based on Carbon Footprint Model
Authors: Li Jiapeng , Sun Ping , Zhang Xuan
Published: September 2020

This paper uses the carbon footprint model to study the carbon emissions of low-carbon campuses. Based on the actual campus conditions, the campus carbon cycle is investigated through field surveys and interviews to discuss the school’s carbon balance and obtain the water, electricity and domestic waste of Tianjin University of Technology. The conclusion that the carbon emissions are large and the emissions of people and cars are small, carbon emissions governance needs to be greatly improved based on the carbon footprint model of low-carbon campus research.
The determination of PAHs in PM10 of different open-source
Authors: Liu Yuanyuan
Published: September 2020

Orthogonal experimental is designed to determine using of L12 (6 * 22) orthogonal, the time is 12 hours and the temperature is 55 °C, dichloromethane amount of 200 ml to extract the best conditions, the best extraction conditions were eight of Jinan City A typical open-source Soxhlet extraction, the extract of the rotary Evaporation, chromatography purification after blowing nitrogen; using GC-MS determination of the content of polycyclic aromatic hydrocarbons. Through the eight kinds of samples of data comparison, the steel dust found in samples of the highest content of polycyclic aromatic hydrocarbons. With the strong carcinogen Dibenzo (a, h) anthracene, 16 in the highest levels of polycyclic aromatic hydrocarbons.
Influence of Ag-based Supported Catalyst via Hydrothermal Synthesis on the Catalytic Treatment Efficiency of Formaldehyde Gas
Authors: Yang Yue , Chen Shanyuan , Wu Taotao , Wang Runmin , Guan Chengli
Published: September 2020

This study aims to explore the influencing factors of the Ag-based supported catalyst synthesized via hydrothermal synthesis method in formaldehyde catalytic oxidation treatment. CeO2 nanorods (CeO2-r) is prepared by hydrothermal synthesis method, and a series catalyst of Ag-K/CeO2-r with different concentrations of active components are prepared by adding active components to the nanorods by maceration method. The best weight hourly space velocity (WHSV), the best concentration of formaldehyde, and the best concentration of active components are studied with the prepared catalysts. When the WHSV is between 26000cm3(g h)-1 and 42000cm3(g h)-1, the maximum conversion rate is at the WHSV of 360003(g h)-1. The different formaldehyde concentrations are set, it is found that when the formaldehyde concentration is 300ppm, the conversion rate of formaldehyde through the catalyst can reach 100%. Under the condition of 300ppm, 360003(g h)-1, the optimal conversion rate of 4%Ag-K/CeO2-r catalyst is found to be the best at all temperatures. Moreover, the physical adsorption of the catalyst is related to whether the catalyst is loaded with auxiliary agent K. In this study, the Ag-based supported catalyst is prepared via hydrothermal synthesis method and the influencing factors of formaldehyde gas treatment are successfully investigated, which lay a solid foundation for further experiments.
A Recyclable Polymer-supported Glycane as pH Buffers for Urease-catalyzed Reaction
Authors: Wang Jiaojiao , Wang Yongguang , Li Yongsheng , Yang Zhiqiang
Published: September 2020

we utilized the PSG beads as polymer-supported buffer agents. Ammonia was measured by the Berthelot method, Buffer activity of the PSG buffers in enzyme-catalyzed reactions at neutral solition was examined for its ability to control the pH of urease catalysed hydrolysis of urea. The urease activity of soybean which analysed using PSG buffers in pH 7. The recycling ability of the PSG was tested. In each cycle, the PSGs were regenerated by HCl and changed into mixed H-Na form by NaOH (H+ form 40% and Na+ form 60%). We demonstrated that PSG exchangers show high buffer activity at neutral pH. The PSG exchangers were effectively used to control the pH of urease catalyzed reactions. The new buffers are as efficient as phosphate buffers in neutral solution but more environmentally benign.
A review of current, temperature and water distribution diagnosis technique for PEMFC
Authors: Ye Qing , Song Jie , Song Pengxiang , Xu Ke , Guo Zhiyuan , Hu Xiao
Published: September 2020

Diagnosis technology is a key means for understanding the electrochemical reaction process of fuel cell. With the increasing demand for high-power stacks in the market, Membrane Electrode Assemblies (MEA) with large active area have been a hot topic. Obtaining the current, temperature, and water distribution information over the entire active area is critical to structural design and performance control of fuel cell. This paper reviews the diagnosis technique that can be used for in-suit measurement of current, temperature, and water distribution. The applicability of various techniques and specific applications in fuel cell diagnosis are summarized, and future developing trend is prospected.