bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research on Vibration of Ship Coupling Beam
Authors: Shuo Chen , Heng Zhang 
Published: February 2021

Abstract
With the continuous progress and development of the military strength of various countries, the concealment performance of submarines has received more and more attention from various countries. It has gradually become an effective way to reduce vibration and noise by studying the vibration and sound radiation characteristics of the propeller-shaft-boat coupling structure. The previous research methods for the vibration and sound radiation characteristics of simple and uniform structures are insufficient in meeting current actual engineering needs. Therefore, it is necessary to explore a more accurate and efficient method for modeling and calculating the complex non-uniform structure of the propeller-shaft-boat.
Kinetic model of methane explosion in a spheroidal explosion tank
Authors: Zhang Xin-Hai , Dou Kai , Luo Zhen-min , Cheng Fang-Ming , Xue Han-ling 
Published: February 2021

Abstract
Methane explosion is studied with a 20-liter content, spheroidal explosion tank. Mixture of methane with oxygen at varied ratio is detonated in the enclosed tank while pressure inside the tank is real-time recorded during the experiments. Temperature and conversion rate of the methane inside the tank during the explosion is calculated according to actual gas equation of state and energy conservation equation. Kinetic equations of the explosion process are derived among conversion rate, species concentration and temperature. Kinetic parameters of the steadily accelerating phase of the explosion process, including the apparent equilibrium constant and enthalpy change, as well as activation energy and pre-exponential factor, are calculated based on kinetic equations and experimental data.
Analysis of the influence of different control modes on the transient power characteristics of DFIG
Authors: Li Zhiping , Cao Na 
Published: February 2021

Abstract
In the event of failure, the doubly-fed Induction Generator (DFIG) with low voltage ride through (LVRT) ability will have different effects on the parallel network characteristics due to the different control mode. In order to analyze the influence of different control modes on the transient power characteristics of DFIG, three kinds of transient response states of wind power system under grid fault are modeled by using power superposition principle based on RSC / GSC controller sampling link and PWM small inertia link, and the accurate transient power response models of different control modes are obtained. The accuracy of the model is verified by simulation with PSCAD/EMTDC, and the influence of control mode on system frequency stability is analyzed.
Probabilistic Load Flow Analysis for Power System Containing Wind Farms Based on Cumulant Method
Authors: Gao Ming , Lv Pan , Zhou Zhuan , Li Jingya , Xue Jingjie , Zhang Bo , Sun Donglei 
Published: February 2021

Abstract
In this paper, a probabilistic load flow computation method based on the cumulants and Edgeworth expansion theory is put forward, and is used in the analysis of system containing wind farms composed of doubly-fed induction generator. Firstly a 2-parameter Weibull function is adopted to fit the random distribution of wind speed, and then the probabilistic model for wind power generator can be established based on active power output characteristic of wind power generator. Based on the linearized AC load flow model, analysis for IEEE 30-node system with wind farm is carried out. Finally the method is compared with Monte-Carlo simulation method, and the effects of wind farms integrated to the operation of power system is analysed in detail.
Experimental study on broaching self-locking anchor rod with mega prestressing force
Authors: Chen Wanbo , Liao Jiehong , Zhou Jianbo 
Published: February 2021

Abstract
In order to solve the problem of applying super-tonnage prestressing force to the gate pier in the process of dam reinforcement, this paper presents a comparative study on the three groups of test specimens of prestressed counterbore self-locking anchor rod and unbonded prestressed anchor cable. T show: (a)both methods satisfy the needs of applying prestress, the experiment conducted on the gate pier that is to be renovated has tested the prestress loss of two schemes and the concrete stress in both free section and anchor section after applying the prestress. The results and counterbore self-locking anchor rod boasts shorter anchorage section and better applicability. (b) the anchorage sections of two schemes generate additional tensile stress, and the maximum additional tensile stress in the anchor rod features 54% less than that of anchor cable, smaller range of additional tensile stress and more reasonable stress state of concrete than that of anchor cable.
Research on Simulation of Heat Transfer Characteristics of Intermittent Spray Cooling
Authors: Han Fucheng , Dong Haihong , Ma Fan 
Published: February 2021

Abstract
Intermittent spray cooling is a new type cooling technology with the energy-saving advantage which can enhance the spray cooling performance and reduce energy was established consumption. In this paper, the three-dimensional simulation model of intermittent spray cooling, and it is the first time using the simulation method to study the heat transfer characteristics of intermittent spray cooling. The simulation results show that intermittent spray cooling effect can be optimized by adjusting spray cycle and duty ratio, and there is the optimal spray cycle and duty ratio at lower flow rate. The simulation results were compared with the experimental results under the same working conditions, and the calculation error was discussed, which is permitted for engineering application.
Study on the Preparation and Performance of An Early Strength Agent for Liquid Alkali-Free Accelerator
Authors: Jiang Yu , Deng Lei , Chen Wenhong , Li Jianmei 
Published: February 2021

Abstract
An early strength agent applied to liquid alkali-free setting accelerator was synthesized at 60°C-70°C by taking methacrylic acid, silicic acid, calcium hydroxide, and hydroxyethyl ethylenediamine as the raw materials. The experiment showed that after 4% early strength agent was added into the accelerator, the 1d compressive strength and 28d compressive strength of the quick-setting mortar and shotcrete were obviously improved, so the industrialized application of this early strength agent can be realized.
Influence of different material proportions on the physical properties of water-saving roof greening substrates
Authors: Wang Bin , Liu Yongxia , Wen Yonghong , Yan Hao 
Published: February 2021

Abstract
The choice of roof greening substrate is the key to effective roof greening. To fully analyze the influence of different material proportions on the physical properties of the substrate, three materials, namely nutrient soil, vermiculite, and ceramsite, are selected, which are mixed with the soil in different proportions to form different roof greening substrates. By measuring the indexes including the bulk density, water absorption rate, water loss rate, and hydraulic conductivity, the variation influence of material proportions on the physical properties of the substrates is analyzed.
Research and Design of Over - irrigation Control System for Underwater Pouring Concrete of Pile Foundation
Authors: Cao Zhen , Wei Yongbin 
Published: February 2021

Abstract
The quality of the pile head is the control difficulty of the concrete cast-in-situ pile technology when the bored piles, especially the deep foundation piles, are filled with underwater concrete. The hammer method and volume estimation method are widely used to control concrete over-irrigation height in the existing technology. However, in the actual operation, these two methods are inclined to cause mis-judgment by the field technicians, so it is difficult to accurately determine the over-irrigation height, resulting in the under-irrigation or the excessively high over-irrigation height of the pile head, which seriously affects the construction quality and greatly increase the cost of engineering costs. In order to solve this problem, combining modern sensing technology and communication technology, an over-irrigation height control system of underwater concrete cast-in-situ pile was developed in this paper based on the principle that the buoyancy changes at a certain depth due to the difference between the mud weight and the concrete proportion of the bored pile. The system is mainly composed of sensor based on Hall effect, data acquisition module, wireless communication module, remote network server and monitoring terminal, and serial tests were carried out. The test results show that the system can accurately monitor the concrete level to reach the pre-set height in advance, and timely alarm for overrun, and it is easy to operate and has high popularization value.
Removal of organic compounds from Microcystis aeruginosa by coagulants and its mechanisms
Authors: Xing Linan , Zheng Mingyue , Zhang Xiaohui , Lu Peng , Xie Guoli , Cao Qiguang , Chen Hongmei , Yang Dongqing 
Published: February 2021

Abstract
Algae organic matter (AOM) has always been a threat to the effective operation of water treatment processes. Coagulation is the most effective way to control the contamination. In this study, AlCl3, PAC and HPAC were investigated as the coagulants. The removal performances were considered by detecting TOC, turbidity, apparent molecular weight (AMW) and fluorescence excitation-emission matrix (FEEM). The turbidity and TOC removal rate can reach 95% when the optimal dosage of PAC and HPAC was 0.04 mol⋅L−1, respectively. For AlCl3, higher dosage is needed. HPAC has a good efficiency on small molecular weight compounds removal. Because there are active adsorption groups and the cationic groups in HPAC. These groups can make the make the AOM lose stability and flocculation through neutralization and adsorption bridging.
Influence of water injection parameters on fracturing effect in coal seam hydraulic fracturing
Authors: Li Liangwei 
Published: February 2021

Abstract
According to the basic parameters of Yangquan mining area, based on the determined meso physical and mechanical parameters and geological parameters, several groups of numerical calculation models considering different fracturing parameters (water injection flow and water injection time) are established. Then, the numerical simulation test of water injection fracturing is carried out by using the particle discrete element program, and the influence effect of related parameters of coal seam hydraulic fracturing is analyzed numerically, the influence of flow rate, pressure, time and other parameters on water injection flow is obtained.
Research Report on Technologies and Equipment for Exploitation of Marine Combustible Ice Resources
Authors: Jin Chaoyue 
Published: February 2021

Abstract
Scientists have been focusing on studying combustible ice as "new energy for the 21st century" due to its wide distribution, abundant reserves, high energy density, low pollution and other advantages. With boundless prospects, however, combustible ice has posed a severe challenge to the existing science and technology of human. Its exploitation technologies have become a key academic research field in the new century. Therefore, it is of vital importance to master scientific payoffs and development trends of Chinese domestic and foreign technologies and equipment for the exploitation of combustible ice and make breakthroughs in its drilling techniques in order to address the energy crisis and carry out the strategic action plan for energy development better in China.
Research on Optimal Utilization of Proven Undeveloped Gas Field
Authors: Zheng Likun 
Published: February 2021

Abstract
X gas field shows a large scale of proven unexploited reserves, however, most of them are characterized by low gas well production, rapid pressure decline, small well control reserves and poor economic benefits. How to economically and orderly develop and utilize these reserves is a difficult problem. By establishing an evaluation system for the existing developed blocks of X gas field, applying the method of multiple regression, establishing a comprehensive evaluation and scoring formula for development effect, taking the proven index data of the development block into the formula for calculating, the comprehensive evaluation score of development and utilization of un exploited reserves blocks, queuing the blocks with productivity and reserves in the new area.This method will provide technical reference for the next development and utilization of X gas field.
Carbon emission reduction cooperation in supply chain with government subsidies
Authors: Li Zhimin , Yang Wen , Pan Yanchun 
Published: February 2021

AbstractEnvironmental sustainability has become the key index to evaluate the success of supply chain management. This paper aims at the problem of joint emission reduction in supply chain with government subsidies under the Cap-and-Trade mechanism(C&T). Three mathematical models considering green technology investment and two subsidy methods are constructed. It is found that government subsidies cannot ensure that enterprises reduce total carbon emissions. Compared with subsidies based on green investment costs, subsidies based on emission reduction have greater emission reductions, but the total carbon emissions are also greater.
Research on frequency Control Strategy of micro grid including wind power and hybrid energy storage system
Authors: Dong Xin , Wang Ruifeng 
Published: February 2021

Abstract
In view of the frequency fluctuation of the micro-grid system containing wind power, hybrid energy storage system composed of batteries and supercapacitors is adopted to coordinate the output, so as to maintain the frequency stability of the micro-grid and provide the possibility for the micro-grid to further absorb wind power and other clean energy. Firstly, by analyzing the characteristics of wind power output, the power deviation signal of the system is decomposed into low-frequency and high-frequency parts through wavelet packet decomposition, so as to maximize the consumption of wind power output power on the premise of meeting the stability of the system. Then, the high frequency part of the power gap is further divided to determine the initial FM power distribution scheme of the energy storage system. Finally, the energy storage output is modified by the Logistic regression function to take into account both the energy storage adaptive frequency modulation and the energy storage charged state self-recovery. Example analysis shows that the proposed control strategy can realize the optimal distribution of wind power, ensure the full utilization of wind farm output, improve wind power grid connection capacity, and increase efficiency and economy.
Research on the Framework of the New Urban Energy Internet Demonstration Project
Authors: Zhang Xiaoyan , Wang Hailong , Wang Bingwen , Huang Kun 
Published: February 2021

Abstract
Energy is the main driving force of economic development and social progress, and the relationship between its production and supply directly determines the destiny of the country. As to the new urban Energy Internet demonstration project, the characteristics and elements of the new urban Energy Internet are analyzed in this paper, and then the overall framework and information integration framework of the new urban Energy Internet demonstration project is proposed. Finally the overall framework and functional requirements of Energy Internet comprehensive management and service platform and the perception layer equipment are proposed, which can provide technical support and framework guidance for the development of new urban Energy Internet business.
Preliminary exploration of energy-saving residential design in hot summer and cold winter area taking Wuhan as an example
Authors: Hu Xueqing 
Published: February 2021

Abstract
In today's architectural design industry, building energy-saving design has become a hot topic, and it is a necessary link for the construction industry to implement sustainable development. However, most areas in China are in hot summer and cold winter. It is very meaningful to design energy-saving residential buildings in combination with the climate to make the buildings more livable and environmentally friendly. This paper demonstrates the design process of a small house in the suburbs of Wuhan, comprehensively considers the building shape, building natural lighting and ventilation, building maintenance structure, the actual application of new materials and new technologies for green house design. At the same time, it combines Ecotect and other computer technology to design the green house. The applied building energy saving technology is analyzed and optimized to provide new ideas for other related designs.
Headspace-Gas Chromatography Method for Determination of Formaldehyde Content in Wastewater
Authors: Xiao-long WANG , Lei ZHANG 
Published: February 2021

Abstract
Through the use of headspace-gas chromatography, the sensitivity and detection limit of formaldehyde content in wastewater obtained by the standard curve method and the standard addition method are compared in order to obtain the best detection method. The results show that the calibration curve correlation of the standard insertion method for testing the formaldehyde content in wastewater is 0.9991, the detection limit of the method is 0.18 mg/L, and the lower limit of determination is 0.69 mg/L. Excellent standard curve method; this method is used for samples with low, medium and high concentrations. The range of standard recovery rate calculated is 85.1%~112.9%, the relative standard deviation in the laboratory is 2.7%~ 6.3%, which is also better than the standard curve method and meets the test requirements. This method is easy to operate, high sensitivity, and low detection limit for the determination of formaldehyde in wastewater, which meets the requirements of analysis and testing.
Research on the Changes of Air Quality in Chengdu During the COVID-19 Pandemic
Authors: Deng Fumin , Zhang Hongjia , Ma Xiaolei , Liang Xuedong 
Published: February 2021

Abstract
As a public health emergency, COVID-19 has greatly affected all walks of life. It also has an impact on the environment. In order to systematically assess the impact of COVID-19 on the environment and the reasons for this impact, this paper takes Chengdu as an example for research. The air quality in Chengdu is analysed from two aspects of time and space, two dimensions of longitudinal and transverse. This paper selects six air pollution indexes (PM2.5, PM10, NO2, CO, SO2, O3)and applies the dual-weight fuzzy comprehensive evaluation method to analyse. The results show that, no matter what the angle is, the air quality in Chengdu has greatly improved during the COVID-19 blockade and the concentration of various pollutants has been greatly reduced. But it's worth thinking about that this situation is always temporary from a longitudinal perspective. With the unblocking and the restoration of industrial production, the air pollution situation begins to return to previous state. This paper provides a reference for studying the changes in air quality during the COVID-19 pandemic and provides a useful supplement for air pollution control.
Effects of magnetic particle proportion and additive amount on the extraction of Pb and Cd from soil by magnetic biochar
Authors: Gong Haofei , Tan Mingxia , Xing Haiwen , Huang Jianjun , Chi Jie 
Published: February 2021

Abstract
Due to the high sorption capacity for heavy metals, magnetic biochar (MBC) has the potential to adsorb heavy metals in soils, which are then removed together with MBC from soils by a magnetic field. However, little research on the magnetic particle (MP) proportion and the addition amount of MBC. In this study, different magnetic particle proportion and addition amount of MBC were evaluated by a batch experiment. The most suitable MP proportion of MBC was 0.2 mol/L Fe2+, under this MP proportion, the extraction rates of Pb and Cd were 42.9% and 37.2%, respectively. The most suitable addition amount was 2.5% under low pollution condition, and 7.5% under severe pollution condition.
Optimization Analysis of System and Air Distribution for Solar and Heat Pump Multi-energy Complementary Zanthoxylum Drying
Authors: Xue Hanling , Wan Xuening , Wu Yehao , Yan Yuting 
Published: February 2021

Abstract
Crops have high moisture content and are easily deteriorated, requiring dry storage. However, the drying energy consumption is relatively large and the drying quality of materials is often affected by the uneven distribution of indoor airflow. Author takes Zanthoxylumas for an example and designs two solar and heat pump drying systems in which the heat pump evaporator and the heat pipe are used to recover the waste heat respectively. The energy efficiency is compared and analyzed, the result shows that when the heat evaporator is used to recover the waste heat, the energy efficiency is higher and COP of the heat pump can reach 4.06. Based on the optimized system, the FLUENT software is used to simulate the airflow organization of the two types that supplying below and returning upward, and the side-supplying and side-returning. The results show that the airflow in the drying chamber has better uniformity when using the side-supplying and side-returning, which satisfies the requirements of Zanthoxylum drying.
Research on the Influence of Environmental Regulation on Enterprise Green Innovation Performance
Authors: Wang GuLei 
Published: February 2021

Abstract
according to summarizing the research status of environmental regulation, expected economic benefits of green innovation and enterprise green innovation per -formance at home and abroad, this paper discusses: (1) the affect of different types of regulation on green innovation performance, and divides environmental regulation into command control type, market incentive type and voluntary disclosure type, and discusses which way of environmental regulation can improve enterprise green innovation performance more effectively; (2) Taking the expected economy of green innovation as an intermediary variable, this paper discusses its intermediary mechanism between environment and enterprise green innovation performance; (3) Divide enterprise green innovation performance into two dimensions: economic performance and environmental performance, and analyze the effect of different kinds of environmental regulations on different dimensions of enterprise innovation performance.
Review on Plants Selection and Application Effects in Ecological Floating Beds based on Water purification
Authors: Zhang Haixia , Han Jianqiu , Chen Fengzhen , Yuan Qingqing 
Published: February 2021

Abstract
Due to the variety of plants and different types of polluted water quality, there is no unified standard for the application types of floating bed plants. Therefore, this paper summarizes and analyses 815 articles related to "ecological floating bed" and "plant water purification" that have been screened and identified in the search results of CNKI. According to plant types and water quality types, the purification effects of floating bed plants on different pollutants are comprehensively described to comprehensively evaluate the actual effects of plants in floating bed applications, which provides a useful scientific reference for the reader to screen and apply the plant in the floating bed.