bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical investigation on the leaked nature gas diffusion of underground gas pipeline through soil to atmosphere
Authors: Zhang Tiantian , Qin Yuxin , Han Dongliang , Luo Zonglin , Tan Yufei
Published: July 2021

When the buried gas pipeline leaks due to corrosion, aging, overload and other reasons, serious safety accidents are easy to occur. In this paper, a three-dimensional numerical model is established to simulate the underground gas diffusion from the directly buried pipeline, through the soil to the atmosphere. Using the model, the diffusion characteristics under the conditions of different initial pipeline pressures and different soil porosities are comparatively simulated and analysed. As indicated by the numerical results, when pinhole leakage occurs, the gas concentration exhibits a symmetrical distribution in the horizontal and axial directions. The gas content gradually reduces, as the distance from the leakage point increases. The diffusion process and gas content are largely determined by the initial leak pressure, as well as the flow resistance in accordance with the soil porosity.
First-principles study on hydrogen storage properties of Ti8C6 cluster
Authors: Wu Xueke , Zhang Song , Zeng Fanju
Published: July 2021

The geometric structure, energy gaps of molecular orbital and hydrogen absorb capacities of Ti8C6 clusters are investigated by first-principles based on density functional theory. The results show that the bond length of hydrogen molecules decrease and the Ti-H bond length of Ti8C6(H2)n clusters increase with the increase of hydrogen molecules adsorbed by Ti8C6 from 8 to 40. Moreover, the Ti8C6(H2)40 cluster not only exhibits strong stability according to energy gap analysis, but also absorbs 40 hydrogen molecules with gravimetric density of 15.05 wt%, which will be considered as a candidate material for hydrogen absorption.
Coordinated Control and Energy Management System of Microgrid Group
Authors: Wang Yanan
Published: July 2021

As an important part of the smart grid, the operation control of the microgrid group is the key technology to maintain its safe and stable operation. The reasonable distribution of microgrid energy is closely related to the stability of system control. Multiple micro-grids in a certain area are uniformly regulated and controlled to form a micro-grid group operation mode. Aiming at the operation and management requirements of the multi-energy complementary microgrid group, the article proposes a design scheme for the energy management system of the microgrid group. The entire system has high operational reliability and economy, and has certain engineering value for improving the comprehensive benefits of the microgrid.
Research basis of muon imaging applied in reactor core monitoring
Authors: Qiao Yanlong , Gao Liang , Fang Qishu
Published: July 2021

Muon imaging technology has been applied in many fields. The exploratory application of muon imaging technology after the Fukushima nuclear accident provides enlightenment for the application of nuclear core safety monitoring under serious accidents. In this paper, the muon imaging technology is introduced from the aspects of technical principle, muon detection technology, imaging algorithm and application, so as to provide ideas and methods for the application of muon imaging technology in nuclear core safety monitoring.
Research on Two-layer Cooperative Optimal Allocation Method of Integrated Energy System
Authors: Li Hua , Liu Dunnan
Published: July 2021

Integrated energy system is one of the effective means to improve the operating economy of China’s energy system, reduce pollution emissions and improve energy utilization efficiency. The upper model solves the planning problem of the integrated energy system, and inputs the planning scheme into the lower model. The lower model realizes the operation optimization of the integrated energy system within the life cycle based on the given planning scheme. Through the iterative updating of the upper and lower models, the optimization of the plan-operation scheme is realized.
Analysis of conductivity of ZnO/LDPE Composites
Authors: Shen Yubo , Zhang Jian , Zhang Dewen , Sun Wei , Zhou Hongyi , Liu Heqian , Zhang Peng
Published: July 2021

The composites prepared by adding zinc oxide into polymer have been widely studied and applied because of their special properties of self homogenizing electric field distribution in non-uniform electric field, inhibiting space charge and electrical tree growth. In this paper, the effects of inorganic filler concentration and particle size on the conductivity of ZnO/LDPE Composites were studied by voltammetry combined with high voltage DC power supply and picoammeter to measure applied voltage and through current.
Lightning Shielding Failure Analysis of High Voltage Transmission Lines Based on Leading Development Model
Authors: Liu Yonghuan
Published: July 2021

Lightning strikes are one of the important causes of line faults. With the increase of voltage levels, the proportion of short-circuit trip accidents caused by shielding strikes is increasing. Therefore, accurate evaluation of the line’s shielding lightning resistance is important for power systems. Its safe and stable operation is of great significance. In this paper, based on the derivation of the pilot development model (LPM) for evaluating the shielding characteristics of the line, taking the 500kV single-circuit line network of the East China Power Grid as the research object, the lightning shielding trip rate and related influencing factors are analyzed and calculated, and the methods for enhancing the lightning protection performance are given. Measures.
Structural Design and Thermal-mechanical Coupling Analysis of a Novel Automobile Magnetostrictive Actuator
Authors: Jia Xingjian , Chu Changbao , Zhou Xiangfeng , Xiao Yue
Published: July 2021

This paper takes automobile disc brakes as the research object, and designs a novel magnetostrictive disc actuator based on the characteristics of large output force, high displacement resolution and fast response speed of giant magnetostrictive material. Based on the vehicle parameters of a new energy vehicle as the design basis, calculate the specific structure and size of the magnetostrictive actuator, and use CATIA software to complete the system parametric modeling, import the built model into COMSOL Multipysics. The simulation results show that the output displacement and output force of the actuator can meet the requirements of braking, and the maximum temperature of the surface of the friction pair is far from the temperature limit of the brake, the rationality of the design and the correctness of the simulation model are verified.
Study on vehicle internal organization fault and performance detection based on mechanical vibration feature extraction
Authors: Hao Lei , Jie Yanliang
Published: July 2021

Vehicle mechanical fault diagnosis is of great significance to ensure the safe and stable operation of vehicle mechanical equipment. The method of vehicle mechanical fault feature extraction based on independent component analysis is studied. Firstly, multi-domain features such as time-domain features, frequency domain features, and EEMD energy features of vibration signals are extracted, and a multi-objective optimization function containing the correlation, monotonicity, and robustness of each feature vector is introduced as the degradation feature evaluation function. Through the independent component analysis of the vehicle mechanical fault signals of different working conditions, the independent components of the signals of various working conditions are obtained, and these independent components contain some inherent characteristics of the vibration signals of the working conditions. Through the vehicle, internal organization fault, and performance testing test, the accuracy and effectiveness of the proposed method are proved, with high prediction accuracy and robustness, which has important guiding significance for engineering practice.
Design of combined heat and power micro grid system in plateau area
Authors: Pu Zewei
Published: July 2021

In order to build a cogeneration microgrid system suitable for the special environment and climate conditions of Tibet Plateau, This paper is mainly through the corresponding generation, transmission and distribution network, to achieve the transmission of electric energy, at the same time reasonable selection of heating equipment and heat dissipation device, under the premise of ensuring the reliability and safety of heating, improve the efficiency of energy utilization, and then achieve the absorption and flexible operation of clean energy (photovoltaic), so as to improve the comfort of the demonstration site.
Phase-Shifted TAB Converter System for Electric VTOL Aircraft
Authors: Fang Zixuan , Callegaro Leonardo
Published: July 2021

This paper investigates a triple-active-bridge converter for an all-electric VTOL(Vertical Take Off&Landing) aircraft, based on the Dual-active-bridge converter, presenting four working scenarios which matching the operating of e-VTOL. The converter adopts a phase-shifting control strategy and decouples the control network. Different targeted settings of the converter system are made for the various operating states of the e-VTOL, and the operating states of the TAB converter in different modes are simulated in MATLAB. The experimental results show that the TAB converter has more diverse operating modes, which can match future e-VTOL use in urban applications.
Design and Research of Transformer Disassembly and Assembly Vehicle with Lifting, Clamping and Pushing Functions
Authors: Ren Shuang , Zhai Guanyu , Qian Yong , Liu Hongwei , Wang Xiaobing
Published: July 2021

The disassembly and installation of distribution transformer is widely involved in the field of distribution network construction and maintenance in power system. In the traditional installation method, cranes and ropes are used to hoist the distribution transformer. Many safety accidents have caused by crane operation. Therefore, it is very necessary to design a special equipment that can successfully install and dismantle the transformers without changing the transverse wire, and fit the narrow space of the two concrete poles on the platform.
Stress analysis of screw connection of key structural components in pump turbine
Authors: Chen Liu , Li Hailing , Yu Jixing , Luo Yongyao , Wang Zhengwei , Zhu Xingbing , Zhao Zhiwen , Lu Xiaokang
Published: July 2021

In the structure of water pump turbine unit, the top cover and the seat ring structure are the key structural components, and the high-strength bolts distributed in the circumferential direction are usually used to connect. With the increase of the unit capacity and size, the number of connecting bolts is increasing gradually, so as to ensure the effective connection of key structural components. Taking a mixed flow pump turbine of a pumped storage power station as an example, the finite element calculation of the joint screw pair structure of the head cover and the seat ring is carried out under different working conditions. The stress distribution law of the screw pair is studied in this paper, which provides important theoretical basis and design reference for the practical engineering application of the head cover ring connection of the pump turbine.
Research on Electric Energy Peak-Valley Time Division Method Based on Supply-Demand Ratio
Authors: Liu Dunnan , Li Hua , Wang Lingxiang , Dong Zhixin
Published: July 2021

With the increase of the proportion of renewable energy, the traditional period division method based on load curve is no longer suitable for the new power system. Considering the development trend of renewable energy, a method for dividing peak and valley periods based on the ratio of supply and demand was proposed. According to the ratio of power supply and load demand, the peak and valley periods were divided by K-means algorithm. By comparing the period division method based on load curve with the period division method based on supply/demand ratio curve, the validity of the peak/valley period division method based on supply/demand ratio proposed in this paper is verified.
Research on the layout of battery pack for plug-in hybrid vehicle
Authors: Yang Guang , Cao Yong , Zhan Guoqiang , Zeng Qi , Chen Qi
Published: July 2021

The layout of battery pack for plug-in hybrid car is usual a difficult problem. The layout analysis involves the balance of battery pack capacity, ride space, passability and other performance. Through dimensional chain analysis, this paper refines each problem, balances each performance, and obtains a reasonable scheme. This paper also studies the layout of the battery for the expansion of electricity. At last, the layout method of battery pack for plug-in hybrid vehicle is summarized.
Parameter Matching and Optimization of Composite Clean Energy Power Supply For PHEV
Authors: Sun Jingxia
Published: July 2021

The idea of composite power supply solves the problem that the specific power and specific capacity of a single battery restrict each other. The specific power of composite power supply is higher than that of a single battery, and the specific energy is higher than that of a single super capacitor, so that the power components are no longer restricted by a single factor. According to the performance requirements of the vehicle, the basic parameters of each component of the vehicle power supply are determined, and then the components are matched reasonably according to their performance advantages to get the appropriate power supply required by PHEV. The parameters of the composite power supply are optimized by using the iterative algorithm of dynamic programming to achieve the best matching of power and energy, and the matching results are verified by simulation.
Research On Clean Energy and New Energy Vehicle by Multidimensional Preference Analysis
Authors: He Chang , Li Qian
Published: July 2021

This paper mainly studies the product selection preferences of consumers of new energy vehicles and the personal attribute factors that affect their selection preferences. By using the multidimensional preference analysis model, consumers can evaluate the preferences of the selected mainstream new energy vehicles and evaluate the product positioning attributes of the vehicles. The results show that consumers have significant preference differences in the product positioning of new energy vehicles. Reliable quality products and economical and practical products are preferred by consumers, while fashion technology products and luxury comfort products have great market potential in the future. In addition, personal attributes including age, income and career stage have an important impact on consumer choice preference.
Study on the Construction Method of Tree Topology in Low Voltage Station Area of Power System
Authors: Fan Jianjun , Sun Jing , Liu Xinzhong , Li Zhimin , Wang Xinku , Cao Shengnan , Lei Jiakun
Published: July 2021

Based on the comparison and analysis of bus topology, star topology, tree topology, ring topology and network topology, the tree topology of low voltage station area is established according to the correlation between output line and input line of each distribution box. Experiments show the realizability of this method.
Power Lines Extraction Using UVA LiDAR Point Clouds in Complex Terrains and Geological Structures
Authors: He Yong , Dong Limeng , Zeng Fanrong , Dong Chengxi , Yao Jianan
Published: July 2021

In order to boost current power line extraction accuracy of transmission lines in complex terrains and cope with uneven point cloud densities, an advanced method for extracting power lines from elevation point cloud features is proposed. First, the elevation filter algorithm is improved by space segmentation and point cloud density analysis to reflect thick extractions of power lines; then, a feature extraction algorithm in which the threshold of Hough line detection decreases along with the increase of elevations is proposed to accurately extract power lines. The improved power line based on elevation feature extraction can effectively solve the problem of incomplete detection of power lines, which attached to the electric tower caused by the undulation of terrains. This research provides a reference for power line extraction and power line early warning of large-scale transmission lines in complex scenarios.
Finite Element Analysis of Peltier Effect based Thermoelectric Energy Conservation Cooling System for Microprocessors
Authors: Chu Weishen , Lv Jiahe , Hong Nan
Published: July 2021

Chip cooling technologies have been attracting researchers’ interests as the wiring density in integrated circuits increases dramatically in recent chip design. A Peltier effect based thermoelectric cooling system is designed for microprocessor cooling. A 3D Finite Element Analysis model is developed to validate, analyse, and optimize the performance of the thermoelectric cooling system. The effects of microcooler size and activation current have been studied by thermo-electric coupled field analysis. It has been found that the Peltier effect based thermoelectric cooling system can successfully reduce the temperature of microprocessors and the optimum activation current for the cooling system has been determined.
Research on Reliability of Grid Connected Photovoltaic Renewable Generation System
Authors: Qadeer Abdul , Huawei Li , Ikram Muhammad Talha
Published: July 2021

Renewable energy sources are increasingly being implemented in power systems to curb global warming and improve generation adequacy. These renewable sources include Hydro, wind, tidal, and solar power systems. Since Pakistan experiences decent solar irradiation throughout the year, the most viable renewable energy option is photovoltaic generation. Before solar systems are implemented, the proposed design is first simulated using design software such as MATLAB-Simulink to correct and adjust parameters to attain the DC voltage and current through the irradiation and environment temperature. Reliability studies and analysis are performed on the simulated systems to ascertain the success and long life before the system components’ failure. In this thesis, the grid-connected PV system’s reliability model established based on the reliability block diagram method using the MIL-HDBK-217F handbook. The handbook provides the methodology of calculating failure rates of specific physical electronics operations. The mean time to failure (MTTF) and Mean time to repair (MTTR) of the system is calculated from the overall system reliability. Photovoltaic power output varies greatly, and it is dependent on solar irradiation and temperature, resulting in intermittent and variable energy production. All of these considerations have a significant effect on the entire system adequacy of the power generation system. This study uses a probabilistic analytical methodology to develop comprehensive reliability models of grid-connected Photovoltaic generation systems.
Enhanced hole extraction in green energy perovskite solar cell by CuOx/spiro-OMeTAD bilayer with improved performance
Authors: Xiao Li , Wang Guanxiong , Yao Jianxi
Published: July 2021

Hole transport layer is of vital important for improving the photo-to-electron efficiency of perovskite solar cells. In this study, we investigate the performance of meso-structure perovskite solar cell applying bilayer materials for improving hole extraction ability. By simulating the performance of perovskite solar cell using wxAMPS software, CuOx is chosen to be ideal candidate of inorganic hole transport material which can moderate device property. The optimized value band offset in schematic diagram shows that photo-generated holes could be extracted from perovskite layer to spiro-OMeTAD efficiently by applying CuOx layer at the interface of perovskite/spiro-OMeTAD. Moreover, the experiment results show that Jsc of device increase to 19.5 mA/cm2, FF increase to 65.9% and total PCE reaches 12.3% by adopting CuOx/spiro-OMeTAD bilayer as hole transfer layer. Simultaneously, hysteresis decreases from 2% to 0.7% and integrated Jsc increase from 14.8 mA/cm2 to 16.03 mA/cm2. The PL results also confirm the mechanism of carrier extraction, which is consist with experimental results. It suggests that applying CuOx/spiro-OMeTAD bilayer is an efficient way to improve performance of perovskite solar cell.
Incremental Capacity Curve Based uniformity analysis for the energy and capacity utilization rate of lithium-ion Batteries
Authors: Zhang Xuenan , Shi Wei , Liu Huan , Zhao Yangmei
Published: July 2021

The consistency problem of the cells will lead to a decrease in the energy and capacity utilization rate of battery, and even cause safety problems. The incremental capacity curve method can be used to study the uniformity of cells and it can acquire the internal parameter status directly, but its accuracy is limited by the curve drawing. This paper proposes a consistency analysis method to obtain the missing points through curve fitting and obtain a high-precision square capacity increment curve. This method uses partial least squares to solve the multicollinearity between feature parameters and introduces the variable projection importance index to judge the importance. Experiments show that after analysis, the rechargeable capacity of the battery can be increased by more than 9% compared with the traditional method, and it has good robustness and accuracy.
Analysis of the memory effect of lithium iron phosphate batteries charged with stage constant current
Authors: Zhao Yangmei , Shi Wei , Zhang Mei
Published: July 2021

Lithium iron phosphate batteries are widely used in various fields and have long been considered to have no memory effect. It is not until recent years that the memory effect of lithium iron phosphate batteries has been discovered and studied. In engineering applications, electric vehicles are usually charged with stage constant current. Here, we first briefly explain the process of memory effect generation. Make the battery have a memory effect under different charging methods. Compare and analyze the characteristics of memory effect under each charging method for optimization ideas of development ChaoJi and other high-power and high-current charging technologies.
Grey Evaluation Method of DC Current Transformer Transient Characteristics in High-Voltage Transmission System
Authors: Ji Feng , Lu Shufeng , Xu Minrui , Chen Gang , Lu Zigang , Guo Jiahao
Published: July 2021

The transient characteristics of the current transformer and its evaluation method are the key factors affecting the protection device, system security, and stability. Therefore, to verify and evaluate the rise time, maximum overshoot, transient delay, and periodic stability of the DC transformer, a DC transformer calibration system is proposed. Based on the calibration system, the index basis of transformer evaluation is obtained, and the evaluation method of DC transformer characteristics based on grey theory is proposed. Finally, through the transient performance test, the transient characteristic parameters of the tested DC transformer are obtained, and its evaluation model is established. Through case analysis, the quantitative evaluation scores of different transformers are given. The method proposed in this paper has an important reference value in the field calibration of the DC transformer.
Study on the oxidation treatment of sodium sulfide by sodium persulfate
Authors: Meng Mei , Gao Pengxuan , Zheng Bo , Liu Zhuang , Chen Xing , Wu Baoyang , Zhao Hanlei , Yang Ziwang
Published: July 2021

In view of a large amount of sulfur ions contained in oilfield sewage, finding an efficient method for desulfurization to reduce the sulfide content of sulfide in oilfield sewage has become one of the topics urgently studied by oilfield workers. In this paper, the oxidation method is used to treat sulfur ions in oilfield sewage, and it is oxidized to harmless elemental sulfur or high-priced sulate. The effects of pH, molar ratio, reaction time, temperature and concentration on the removal rate of sulfur ions were investigated. The optimal reaction conditions were determined that the initial concentration of simulated water was 75 mg/L, pH=8, the molar ratio of sodium persulfate and sodium sulfide was 1.2: 1, the reaction time was 30 minutes. The maximum removal rate of sulfur ions by sodium sulfate can reach 96.11% at 35°C.
A novel state of health estimation method for lithium-ion battery based on partial incremental capacity and Support vector regression
Authors: Yang Bo , Jin Peng , Liao Xiawei , Ma Xiaomin , Sun Wei
Published: July 2021

State of Health (SOH) is critical for lithium-ion batteries as it ensures the safety of batteries’ health condition and provides a basis for retirement of the batteries. In order to provide an accurate estimation of the SOH, a novel hybrid estimation method based on the partial incremental capacity and Support vector regression (SVR) is proposed in this paper. Firstly, the Savitzky-Golay method is applied to smooth the initial incremental capacity curves under the period of constant current charge. Then the key health features are extracted from the partial incremental curve theoretically and selected through correlation analysis methods. Finally, an SVR model is constructed to estimate the SOH. Several battery datasets under different cycling test conditions are used to validate the effectiveness of the proposed method. The result shows that the proposed method can provide a reliable and accurate estimation for SOH.
Study on treatment technology of industrial and mining wasteland in Shenmu City
Authors: Shi Lei , Yang Liangyan
Published: July 2021

In order to implement the basic state policy of cherishing and rationally using land and strictly protecting cultivated land, effectively break the bottleneck of strategic resource development and urban development, optimize the land use structure, raise the level of economical and intensive land use, promote the balance between urban and rural areas and the sustainable economic and social development, and realize the overall development and protection of cultivated land. In the pilot project of reclamation and utilization of historical abandoned industrial and mining lands in Shenmu City, management requirements such as total control of resource utilization, two-way regulation of supply and demand and difference are implemented to standardize the reclamation and utilization behavior of abandoned industrial and mining lands. The waste residue covered by the mining area shall be stripped and cleared, the buildings and structures in the mining area shall be dismantled, and all the waste residue and construction waste shall be transported to the designated accumulation point. Then, as needed, it will be cleared into farmland, forests, grasslands and rivers. Results: The reclamation area of the project covers 42 plots, with a total area of 2146.4 mu. The construction scale of the project is 124.8122hm2. Through the reclamation of abandoned industrial and mining land, 22.1038hm2 of new cultivated land was added in the project area, with a rate of 17.71%. The new grassland area was 32.2119hm2. After reclamation, the land utilization rate of the project increased significantly, reaching 93.38%. It promotes the balance of dynamic indexes of cultivated land in Shenmu City, maintains the dynamic balance of total cultivated land in Shaanxi Province, and improves the production and living conditions of local farmers. The project has great ecological benefit, obvious social benefit and certain economic benefit. The unification of social benefit, economic benefit and ecological benefit is realized, which accords with the goal of industrial waste land reclamation.
Research on Optimal Operation Strategy of Distributed Energy Based on Distribution Network Planning
Authors: Zheng Liming , Sun Min , Xu Genqi , Zhang Zhengbo
Published: July 2021

Distributed energy is an energy supply mode based on load demand side. It aims at maximizing energy utilization and environmental benefits, integrates and optimizes various energy demands and resource allocation of users, and adopts a new energy system with demand response design and modular allocation. Because most of the energy it consumes is renewable and clean, it is environmentally friendly. Energy community is an important part of active distribution system. The method of power grid planning is studied and analyzed, and the energy management model of energy community is established. On this basis, the active distribution system is studied comprehensively and solidly. The research results can effectively improve the economy and reliability of active distribution system, and promote the large-scale grid connection of renewable energy. By using the heat storage system to periodically transfer heat load, the contradiction between the ratio of electric load to heat load in microgrid and the electric heat ratio of cogeneration system can be alleviated, thus realizing efficient and economical electric heat dispatching.
Performance Test and Application Research of New Gemini Wetting Dust Suppressant
Authors: Li Ming , Qiu Linling , Yang Huaizhen , Fei Xudong
Published: July 2021

In order to solve the problem of low efficiency of dust-catching by water mist to the hard-to-wetting and respirable dust, a new wetting type dust suppressant of Gemini was proposed based on the analysis of the wetting effect of water mist. Based on the evaluation indexes of surface tension, contact Angle, wetting and settling rate of dust spray, the performance of polyquaternary ammonium salt AG-101, dodecanol polyoxyethylene etheryl dimethyl ammonium chloride, octyl alcohol polyoxyethylene etheryl dimethyl decyl ammonium chloride and macromolecular cationic PCD Gemini surfactants were optimized, and had carried on the dust-suppression performance in a certain open-pit iron mine field experiment research. The results show that the comprehensive dust suppression performance of mass concentration of 2.0% of quaternary ammonium salt polymer AG-101 is the best, indoor experimental tests showed the dust rate is 4.2 times the speed of water, the field test showed that the initial wetting speed is 4.4 times the speed of water, and the action time of dust and water mist suppression is shortened obviously. The field application proves that the total dust removal efficiency is 82.3% (water is 56.6%), which is 45.4% higher than that of water. The dust removal efficiency of respirable dust is 92.1%, which is 16.5% higher than that of water. The research results provide a new dust suppressing agent for optimization of mine spray dust removal.
The Application of Nanoenzymes in Biology Detection
Authors: Li Yifei
Published: July 2021

Nanozyme is a special kind of artificial mimic enzyme of chemical synthesis that has the unique properties of nano-materials as well as the catalytic efficiency and enzymatic reaction kinetics similar to natural enzymes. With all its specific features, Nanozyme has the advantages of good stability, low making cost and easy preparation, overcoming the shortcomings of the complicated preparation and purification process of natural enzymes and their changeable catalytic activity and stability which is easily affected by outside restrictions. Based on its unique superiority, nanozyme has exhibited broad prospects for its practical application in many fields of chemical detection, especially in environment and biology. With different designs of compositions and morphological forms, nanozymes enable quick and relatively accurate detection of nucleic acid, macro-molecular substances, like micro-molecular substances like glucose, hydrogen Peroxide in certain tissues, which surely casts a bright light on the convenient and effective test in biology.
Simulation-based sensitivity analysis and optimization of narrow strip electrostatic sensor
Authors: Chen Jiange
Published: July 2021

Aiming at the problems of low sensitivity and large interference to the dust flow field when the rod electrostatic sensor detects pipe dust, the narrow strip electrostatic sensor is proposed in this paper. Firstly, the high fidelity 3D finite element model of narrow strip electrostatic sensor, pipe and dust particles is established by COMSOL software. By gridding the model, the electrostatic field distribution in the pipeline under the action of charged dust is simulated. Then the spatial sensitivity distribution of the narrow strip electrostatic sensor in the dust pipe is analyzed. Finally, the influence of the length, width and thickness of the strip electrostatic sensor on the spatial sensitivity of the narrow strip electrostatic sensor is analyzed, which provides a basis for the structural design of the high sensitivity narrow strip electrostatic sensor.
Study on Treatment of Mineral Processing Wastewater by Ozone Combined Catalytic Oxidation
Authors: Chen Guoqiang , Chen Bin , Yang Xiaosong , Shao Linan , Sun Chao
Published: July 2021

At present, most non-ferrous metal mines treat Mineral Processing Wastewater by natural degradation of tailings pond. Some residual mineral processing agents were decomposed after the waste water passed through the tailings pond, but a large number of mineral processing agents remained in the water quality could not meet the discharge standard requirements. Conventional oxidation process has disadvantages of large dosage and high cost. In this study, ozone composite catalytic oxidation method was used to treat COD of mineral processing wastewater. According to the experimental results, when the dosage of homogeneous catalyst Mn2+ was 2mg/L, the volume ratio of heterogeneous catalyst dosage wastewater and KYO-1 catalyst was 3:1, and the dosage of ozone was 20mg/L, COD of wastewater after oxidation decreased from 155 to 35mg/L.It meets the discharge standard and the operation cost is about 0.8 yuan/ton of water.
Exposure to dibutyl phthalate induced the growth inhibition and oxidative injury in Dunaliella salina
Authors: Wei Chenghui , Wang Shuang , Hu Xiaochen , Zhang Jing , Chen Jie , Zhang Qichen , Wang Yuan , Wei Jie
Published: July 2021

Dibutyl phthalate (DBP) is a persistent organic pollutant that poses a threat to aquatic ecosystems. In order to study the ecological toxicological mechanism of DBP on marine microalgae. Dunaliella salina was chosen as the experimental material. We investigated the cell growth, hydrogen peroxide (H2O2) content, malondialdehyde (MDA) content, superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities of D. salina exposed to different DBP concentrations. Exposure to low concentrations of 0.1 mg/L DBP promoted the cell growth of D. salina. As the concentrations of DBP increased, the growth of D. salina was gradually inhibited. The GPx and SOD activities of D. salina reduced significantly exposed to DBP concentrations of 50 and 100 mg/L. When D. salina was exposed to 100 mg/L DBP, the MDA and H2O2 contents of D. salina increased with time from the second day. The results provided theoretical support for studying the toxicity mechanism of DBP.
A New Method for the Dynamic Comprehensive Evaluation of Regional Eco-efficiency: Evidence from Jiangsu Province
Authors: Peng Fang , Zhang Ling , Shi Yun
Published: July 2021

Regional eco-efficiency is an important indicator for observing the harmonious coexistence of man and nature, which also provides a quantitative idea for the observation of the effect of China’s Ecological Civilization Construction. Among the various studies of regional eco-efficiency evaluation, problems of interacting indicators and dynamic comparisons are still waiting to be resolved. Based on this situation, this paper proposes a new evaluation approach, integrating bi-capacity, VIKOR method and time series entropy technology, to explore the dynamic comprehensive evaluation of regional eco-efficiency. Eco-efficiency performances of 13 cities in Jiangsu Province during 2014 to 2018 are also be calculated by this new approach in case study.
Design of electronic delay ignition device for a certain type of HESH
Authors: Zhang Xinhua , Miu Yingbing , Niu Yuqiu , Shang Wei
Published: July 2021

Aiming at the low precision of the gunpowder delay body of a certain type of HESH (High-explosive squash-head), an electronic delay ignition device was used to replace the traditional delay body. The design uses an independent setter to charge the electronic delay ignition device, set the delay time and detect the online status,etc. The delay time of HESH can be adjusted within the predetermined range, and the precision of the delay ignition time can be improved from 0.6s to 0.03s,which can obviously improve the performance of HESH.
A Multi-point Masonry Method for Small Revetment of Concrete Pole Embankment
Authors: Ren Shuang , Qian Yong , Chen Xiuhui , Wang Xiaobing , Shen Amei
Published: July 2021

At present, in order to prevent the water flow of rivers, streams, spillways, fish ponds and field ditches from soaking and eroding the line foundation, it is often necessary to build revetment to the poles near these waters. In order to completely eliminate the disadvantages of traditional revetment, we need to design the revetment suitable for power concrete pole.
A FEA Method for Deformation Characteristics of Circular Cylindrical Shells Compressed by Two Rigid Plates
Authors: Zhang Ziqian , Yang Huilin , Zhao Fei , Jiang Nianshun
Published: July 2021

Circular cylindrical thin shells as one of the most energy absorbing elements are used in various engineering applications. One of the most important applications is compressing shells laterally between two rigid plates. Many researchers have work on this issue, but it is hard to be analyzed by the theoretical methods. In the present paper, a finite element model was developed to resemble the compressive process of circular cylindrical shell by two rigid plates laterally. Then a dynamic simulation was carried out using ANSYS LS-DYNA program. The cross-sectional profile and Mises stress distributions as well as the load–displacement curve was obtained by the FEA process, which can reveal the main deformation characteristics of circular cylindrical shells compressed between two rigid plates.
Development and Application of Energy Environment Ecological Control Integrated System in A Steel Company
Authors: Yuan Zhipan , Ma Zhichong , Tang Yunlan , Wang Mengyuan
Published: July 2021

Energy environmental ecological system with traditional design pattern to design and evaluate different phases in order, in view of the A steel company., energy and environment ecology and ecological management status, and the requirement of new industrialization, the development of A steel company., energy and environmental ecological integrated control system, this paper introduces the A steel company., co., LTD., the actual application shows that, The ISEE system developed by our company improves the ability of energy and environment ecological management, has significant ecological benefits, and has strong promotion and application value. This paper gives some practical suggestions on the effective application of ISEE model for the improvement of the actual engineering type environment.
Evaluation of Energy Consumption of Typical Asphalt Pavement Structure
Authors: Zou Bo , Yang Fei , Fu Jiancun , Wang Kai , Liu Fangtao
Published: July 2021

The energy consumption of asphalt pavement during construction is analyzed according to life cycle theory. The energy consumption boundary of each asphalt pavement structure layer during construction period is clarified. The energy consumption of each link of asphalt pavement is analyzed, and the key nodes of energy consumption control during construction of asphalt pavement are identified. At the same time, by comparing the energy consumption of different types of mixtures, new energy-saving and emission reduction technologies are recommended.
Study on stresses of head cover bolts in a pump turbine based on FSI
Authors: Luo Yongyao , Chen Funan , Chen Liu , Wang Zhengwei , Yu Jixing , Zhu Xingbing , Zhao Zhiwen , Ren Shaocheng , Li Jinwei , Lu Xiaokang
Published: July 2021

The stresses of head cover bolts in a pump turbine were analyzed based on Fluid-Structure-Interaction (FSI). A nonlinear finite element model including head cover, bolts and stay ring was set up by means of contact elements, two head cover models with different flanges were set up to evaluate the effect of head cover to bolts. Results showed that both the uneven pressure distribution and the uneven head cover structure along the circumference have great influence on the stresses of the bolts. In this study, for the head cover with double flange, the single bolt has larger axial stresses amplitude along the outside circle, and the average values of the axial stresses for the 96 bolts are larger too, as a result, the bolts have higher average relative stiffness.
Research of Fenton-like Catalysts for Remediation of Organic Pollution in Sewage Treatment Technology
Authors: Luo Yuhu , Wei Yang
Published: July 2021

Supported Fenton-like catalysis has the advantages of wide application range, high catalytic efficiency and easy recycling. This article reviews the preparation methods of supported Fenton-like catalysts and analyzes the degradation effects of different carrier catalysts on organic pollution, in order to provide necessary reference for the remediation of organic pollution.
A Building Information Modelling (BIM) Approach to the Systematic Management of Construction Projects
Authors: Ershadi Mahmoud , Jefferies Marcus , Davis Peter , Mojtahedi Mohammad
Published: July 2021

Recent advancements in information technology have benefited the construction sector in more effective storage, analysis, and transmission of information. Making proper project decisions is hinged upon the verified and timely information provided by systems. It is especially the case in large construction projects in which many partners collaborate to deliver a project. Building information modeling (BIM) as an intelligent 3D model-based approach provides construction managers with insight on how to integrate elements of project configuration. In this paper, we theorize the potential contribution of BIM to the systematic management of projects at the project and corporate level. The findings guide practitioners on how to take advantage of this approach towards the integrated planning and control of construction projects.
Double single-channel Kondo coupling in graphene with Fe molecules
Authors: Vicent I M , Chirolli L , Guinea F
Published: July 2021

We study the interaction between graphene and a single-molecule-magnet, [Fe
4(L)2(dpm)6]. Focusing on the closest Iron ion in a hollow position with respect to the graphene sheet, we derive a channel selective tunneling Hamiltonian, that couples different d orbitals of the Iron atom to precise independent combinations of sublattice and valley degrees of freedom of the electrons in graphene. When looking at the spin-spin interaction between the molecule and the graphene electrons, close to the Dirac point the channel selectivity results in a channel decoupling of the Kondo interaction, with two almost independent Kondo systems weakly interacting among themselves. The formation of magnetic moments and the development of a full Kondo effect depends on the charge state of the graphene layer.
Almost minimizers for certain fractional variational problems
Authors: Jeon S. , Petrosyan A.
Published: July 2021

A notion of almost minimizers is introduced for certain variational problems governed by the fractional Laplacian, with the help of the Caffarelli–Silvestre extension. In particular, almost fractional harmonic functions and almost minimizers for the fractional obstacle problem with zero obstacle are treated. It is shown that for a certain range of parameters, almost minimizers are almost Lipschitz or

C

1
,
β

C^{1,\beta }

-regular.
Growth theorems for metric spaces with applications to PDE
Authors: Safonov M.
Published: July 2021

The paper is devoted to some extensions of the joint results by N. V. Krylov and the author on the Harnack inequalities for second order elliptic and parabolic equations in nondivergence form to metric spaces of homogeneous type. The main tools are special Landis-type growth theorems.
Zero tolerance to sexual harassment in surgical training in the UK
Authors: Boffa C , Ceresa C D L , Vig S , Knight S R , Royston E , Quiroga I , Sinha S
Published: July 2021

Sexual harassment exists within the surgical training community and environment. This is unprofessional behaviour and the surgical community must raise awareness of it as well as facilitating and encouraging reporting with robust investigation pathways.
Accurate axillary staging by superparamagnetic iron oxide-enhanced MRI at 1.5 T with fat-suppression sequence as an alternative to sentinel node biopsy in breast cancer
Authors: Motomura K , Tabuchi Y , Enomoto Y , Nishida T , Nakaoka T , Mori D , Kouda M
Published: July 2021

Superparamagnetic iron oxide (SPIO)-enhanced MRI at 1.5 T with fat-suppression sequence is useful for the detection of metastases in sentinel nodes localized by CT lymphography in patients with breast cancer. SPIO-enhanced MRI may offer an alternative to sentinel node biopsy and avoid axillary surgery itself for patients with breast cancer who have negative sentinel nodes on SPIO-enhanced MRI.
Meta-analysis of randomized controlled trials and individual patient data comparing minimally invasive with open oesophagectomy for cancer
Authors: Müller-Stich B. P. , Probst P. , Nienhüser H. , Fazeli S. , Senft J. , Kalkum E. , Heger P. , Warschkow R. , Nickel F. , Billeter A.T. , Grimminger P. P. , Gutschow C. , Dabakuyo-Yonli T. S. , Piessen G. , Paireder M. , Schoppmann S. F. , van der Peet D. L. , Cuesta M. A. , van der Sluis P. , van Hillegersberg R. , Hölscher A. H. , Diener M. K. , Schmidt T.
Published: July 2021

Background

Minimally invasive oesophagectomy (MIO) for oesophageal cancer may reduce surgical complications compared with open oesophagectomy. MIO is, however, technically challenging and may impair optimal oncological resection. The aim of the present study was to assess if MIO for cancer is beneficial.

Methods

A systematic literature search in MEDLINE, Web of Science and CENTRAL was performed and randomized controlled trials (RCTs) comparing MIO with open oesophagectomy were included in a meta-analysis. Survival was analysed using individual patient data. Random-effects model was used for pooled estimates of perioperative effects.

Results

Among 3219 articles, six RCTs were identified including 822 patients. Three-year overall survival (56 (95 per cent c.i. 49 to 62) per cent for MIO versus 52 (95 per cent c.i. 44 to 60) per cent for open; P = 0.54) and disease-free survival (54 (95 per cent c.i. 47 to 61) per cent versus 50 (95 per cent c.i. 42 to 58) per cent; P = 0.38) were comparable. Overall complication rate was lower for MIO (odds ratio 0.33 (95 per cent c.i. 0.20 to 0.53); P < 0.010) mainly due to fewer pulmonary complications (OR 0.44 (95 per cent c.i. 0.27 to 0.72); P < 0.010), including pneumonia (OR 0.41 (95 per cent c.i. 0.22 to 0.77); P < 0.010).

Conclusion

MIO for cancer is associated with a lower risk of postoperative complications compared with open resection. Overall and disease-free survival are comparable for the two techniques.