bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of out-of-service wells on soil condition
Authors: Zhichkina L , Nosov V , Zhichkin K , Mirgorodskaya M , Avdotin V
Published: January 2020

The purpose of the research it to evaluate the degree of chemical contamination of soil in and around wells located in the Buzuluksky Bor National Park. The research found oil pollutants in the soil cover of the №6, №8, and №229 Nekludovskaya wells areas. Category of pollution by oil products is dangerous, oil products content in № 8 Nekludovskaya well area is 27 MAC, in № 6 Nekludovskaya well area - 19.5MAC, in № 229 Nekludovskaya well area - 9.7 MAC. Soil cover in № 6 Nekludovskaya, № 229 Nekludovskaya, № 6 Koltubanovskaya and Mogutovskaya wells areas is polluted by oil products and heavy metals, and is subject to remediation or conservation.
An ecological analysis of the composition and condition of woody plants in urban and suburban ecosystems of the Khopyor River Region
Authors: Larionov M V , Soldatova V V , Logacheva E A , Larionov N V , Ermolenko A S
Published: January 2020

The aim: to perform research of the species composition and condition of urban and suburban ecosystems of the Khopyor River Region. The route method was used for the species composition of woody plants. Also, using this method the conditions of the growth of trees and shrubs were described. The data of field ecological observations and researches were analyzed in the laboratory conditions. Plant species were identified by means of determinants. The geographical analysis and floristic belonging of plants in towns and villages is carried out. A diagnostics of the vital state of woody plants is carried out according to the complex of their external signs on ecologically different territories. It is found that the greatest species diversity is characterized by the family Rosaceae Juss. The poverty of the species composition of woody plants in the towns and villages of the research area is associated with insufficient introduction. The largest number of species of trees and shrubs in urban areas are characterized by parks and squares. Of great concern is the weakening of the vital condition of woody plants in the area of suburban highways. The greatest values of damages of the objects of the research are revealed at wood plants as part of roadside territories of towns and villages. The expediency to restore greening in ecologically problematic urban areas is obvious.
Consulting: Russian practice of economy greening
Authors: Piskorskaya Svetlana Yu , Malanina Yulia N
Published: January 2020

The article deals with the problem of greening the economy and the formation of the environmental services direction. Analyzed are the specifics of environmental consulting, identified the main activities falling under the definition of “environmental consulting”: environmental certification of equipment, production, plants and natural objects and territories; conducting integrated environmental-economic analysis of the functioning of existing and planned industrial facilities; environmental consulting environmental protection enterprises. The practice of Russian professional environmental consulting is presented and the activities of consulting agencies are listed. The Russian environmental consulting is focused on rendering a complex of services on ecological safety of the organizations and filling of the corresponding reporting and documentation. The basic principles of reporting on environmental activities of enterprises are given. The main aspects of environmental legislation of the Russian Federation are considered. A general idea of environmental consulting as a business policy is formed, including understanding of environmental problems, environmental monitoring and environmental audit of enterprises and organizations to identify areas of their environmental activities. It is proved that environmental consulting is necessary for most enterprises and organizations, especially those engaged in the field of environmental management.
Numerical simulation of a flow mixer for a radial type chemical reactor
Authors: Solovev S A , Soloveva O V , Gilmurahmanov B Sh , Lamberov A A
Published: January 2020

In this work, we performed mathematical modeling of internal elements for mixing the reaction flows. The reactor of the dehydrogenation of ethylbenzene to styrene process was studied. A variant of a radial type reactor in which the gas flow is from the bottom up is considered. Ethylbenzene and steam were selected as components for mixing. Ethylbenzene is supplied to the mixer at a temperature of about 600°C, and steam at a temperature of about 700°C. Three design cases for the internal devices of the mixer are considered. The analysis of the gas mixture parameters, such as volume fraction and average temperature, at the outlet of the mixer was carried out. The cases with the best mixing of the components are determined.
On the problem of increasing the efficiency of UAVs technologies in agrarian business
Authors: Kovalev I V , Karaseva M V
Published: January 2020

The article considers the technological and economic application efficiency of the aviation unmanned systems in agrarian business. The most effective types of work for agricultural unmanned aircraft have been identified taking into account the global trend towards the introduction of precision farming technologies. The conversion of manned aircraft into unmanned aerial vehicles is also pointed out in the field of unmanned aviation. It is typical for cargo UAVs. The unmanned version of the AN-2 aircraft is an efficient transport platform for moving goods in rural areas, i.e., in the absence of financially costly infrastructure of modern airfields and airstrips. A mathematical model for the biotechnological system of the technological process in processing crops with aircraft of various carrying capacities is studied. The task of optimizing the aircraft load with chemicals is considered for two technological schemes for organizing their refueling with aviation fuel.
Using biological protective agents in turkey farms
Authors: Gainullina M K , Volkov A K , Yusupova G R , Yakimov O A , Dandrawy M K
Published: January 2020

This research aimed to study the effect of adding new feed additives “Asido Bio-TCIT” in drinking water” in a dose of 1.0 ml/head/day on the productivity and hematological characters of turkey poults “BIG-6 “cross. Results showed that using of “Asido Bio-TCIT” leads to an improvement in the main production indicators of growth and development of turkeys; survival rate increases by 4.0%;the average daily gain in live weight is increased by 13.1%; feed costs per 1 kg live weight are reduced by 9.88%;the mass of gutted carcasses of the experimental group is higher than the control by 12.3%;the liver mass of the carcasses of the experimental group is higher than the control by 14.8%, and the heart weight is more by 17.9%.In addition to, total blood proteins show marked increase in the experimental group turkeys by 3.02 % compared with the control group. On biochemical analysis, a significant difference was observed in increase in the amount of hemoglobin and red blood corpuscles in the experimental group of turkeys by 8.82%, 8.29%, respectively.
The efficiency of the spring wheat production process depending on the seeding rate in the arid zone of Mongolia
Authors: Litvinova V S , Bopp V L , Kurachenko N L , Shmeleva Zh N
Published: January 2020

The paper presents the experience of assessing the efficiency of the spring wheat production process depending on the seeding rate in the arid zone of Mongolia. The research was conducted in 2017 at the experimental field of PROLOG SYSTEMS LLC (Mongolia). The experiment used different norms of wheat varieties Novosibirskaya 15. Arable chestnut soils for land use in PROLOG SYSTEMS LLC have the light granulometric composition, characterized by a shortage of productive moisture and a low level of potential fertility. Low availability of humus, alkaline reaction, very low availability of mobile phosphorus, low-exchange potassium significantly reduce the productivity of the company’s fields. The evaluation of wheat biometric indicators revealed the dependence of plant height, spikelets number in the ear and productive bushiness on the seeding rate. A lower seeding rate in the arid zone of Mongolia reduces species competition between plants before the bushiness phase, but increases it in later phases of plant development due to the increased productive bushiness. Also, crops of wheat varieties Novosibirskaya 15 in Mongolia with an optimal seeding rate of 140-180 kg/ha had more intensive growth, maximum yield and minimum lodging compared with a higher seeding rate of 210-230 kg/ha. The decrease in the seeding rate is permissible in hot and arid conditions of Mongolia, while the presence of productive moisture in the spring period will be a determining factor.
Export potential development of wild plants
Authors: Rozhkova A V , Dalisova N A , Stepanova E V , Karaseva M V
Published: January 2020

The article presents the prospects for the wild plants export development in Krasnoyarsk Krai. The analysis of the wild plants export from the region over the past five years is carried out. The commodity structure of the wild plants export was revealed and the main foreign trading partners were identified. The article considers factors and prospects for the development of wild plants harvesting and sending them for export on the example of Krasnoyarsk Krai.
Effect of Starting Microstructure in High Speed Steel on the Grain Refinement Potency of Electropulsing Treatment
Authors: Zhang Jiatao , Hu Penglei , Li Xiongqi
Published: January 2020

High speed steels (HSSs) are widely used materials for tools production, which grab a third part of the global cutting tool market. Heat treatment is an indespensable process for the fabrication of HSS tools. Modifications of carbides and grain size of the matrix are two main aspects for the heat treatment of HSSs. In order to obtain better wear property, hardness or red hardness, modification of carbides attracts more researchers’ attention, but grain refinement benefits to the toughness and tool life. Compared with the grain refinement methods used for other steels, such as controlled rolling, available method for grain refinement of HSSs seems deficient. Our previous study provided a new method to produce ultrafine grained M2 steel, but the effect of the starting structures on the grain refinement potential of electropulsing treatment (EPT) was not involved. Results in this work show that the grain size can both be refined or even ultra-refined by EPT, whatever the difference in the starting structures. But the austenite transformation of the matrix was completed at lower peak temperature when using starting tempered structure. And the pre-tempered M2 samples have higher hardness than that obtained after heat treatment or EPT when using the starting annealed structures.
Analysis of Centroid Variation of Three-floating Gyroscope Based on Error Sensitivity
Authors: Zhang Jialun , Li Yi , Zhang Faping
Published: January 2020

The surface error of the three-floating gyroscope caused the centroid variation of the three-floating gyroscope, which caused the navigation accuracy to decrease. In this paper, the error sensitivity model of three-floating gyroscope was established by using the geometric error transfer theory, the influence of each surface error to the three-floating gyroscope’s centroid was calculated, and the results were verified using modeling software. Finally, this paper evaluated the assembly capabilities of the assembly surface. This paper has guiding significance for the three-floating gyroscope to reduce production cost under the premise of ensuring navigation accuracy.
Design of the remote-control system for PM2.5 capture device
Authors: Wang Wan , Lu Yanlin , Zhang Zuo , Wang Tianzhi
Published: January 2020

PM2.5 is the main factor of haze formation. This paper designed a remote control system for PM2.5 capture device by using combined strategies, which were redundant structure, acoustic vibration and reverse blowing. The remote control system is composed of Siemens PLC s7-200 series CPU, software and hardware. The system was simulated by Siemens S7200 SIM programming. The combined strategies realized the continues work. In addition, remote monitoring of the PLC control system implemented to make remote operation more convenient.
Study on Preparation and properties of low sensitive polycarboxylate superplasticizer
Authors: Guan Mengqin , Li Xianghe , Jiang Zhuojun , Guo Xinqi
Published: January 2020

Esterified macromonomers (P1) were obtained from methacrylic acid(MAA), maleic anhydride(MAn) and methoxy polyethylene glycol monomethyl ether (MPEG). A low sensitive polycarboxylate superplasticizer (P-DMG) was prepared by copolymerization of Esterified macromonomers (P1) with acrylic acid (AA), hydroxyethyl acrylate (HEA), acryloyloxyethyl trimethyl ammonium chloride (DAC) and 4-hydroxybutyl vinyl polyoxyethylene ether (VPEG). Compared with the conventional polycarboxylate superplasticizer, P-DMG can reduce the sensitivity to concrete dosage, water consumption, temperature and raw materials, and has good workability. It can be widely used in various concrete projects.
Quantitative analysis of Satellite counterweight and Influencing Factors
Authors: Zheng Jian Dong , Zou Chen , Xiao Pi Li , Xue Bi Jie , Zhong Hong Xian , Zhang Lei , Zou Shuang , Yang Wen
Published: January 2020

Counterweight will increase with the use of more and more load equipment. More counterweights in satellite will reduce weight percentage of load equipment, consume fuel and short the lifetime of satellite on orbit. Firstly, this paper analyzes the relative factors with counterweight, and the relationships between them. That is, the relationships between counterweight and designed centroid from satellite layout, centroid error from product and computational error, installation scheme and error of 490N engine, as well as the disturbance torque value. Then the way to reduce counterweight is approached.
Effect of mechanical juice extraction method on the quality of fresh-squeezed apple juice
Authors: Wang Zhengchen , Cui Huanyong , Fan Shichao
Published: January 2020

In order to study the effect of different mechanical juice extraction methods on the quality of fresh-squeezed apple juice, the optimal fresh-squeezed apple juice processing method was selected. The fresh-squeezed apple juice is processed by three kinds of mechanical juice extraction methods: squeezed juice, spiral juicer and broken juice. Five main evaluation indexes of soluble solid content, titratable acid content, value of b*, value of a* and 625nm transmittance of fresh-squeezed apple juice obtained by three mechanical juice extraction methods were determined. Through the analysis and research of the data obtained from the five indicators, the influence of different mechanical juice extraction methods on the quality of fresh-squeezed apple juice was determined, and the mechanical juice extraction method suitable for processing fresh-squeezed apple juice was determined.
Study on the preparation high performance microfiber glass blanket with high water resistance for buildings
Authors: Hao Xiaotian , Wang Qingjiang , Wang Hailong
Published: January 2020

The high performance microfiber glass blanket with high water resistence is mostly used as insulation and sound absorption materials in the construction field, such as roof insulation materials, wall insulation materials. The high performance microfiber glass blanket was prepared by centrifugal method with spraying binder. The influence of fiber diameter and aging time on the water resistance, strength, filtration efficiency and resistence was investigated. The results show that the optimum kiln pressure is 24±2Pa, kiln temperature is 490±5°C and leakage current is 787±5mA); the optimum dosage of phenolic resin compound and water-resistant agent is 7% and 0.4% respectively; the fracture strength of the prepared samples in the direction of length and width is better than that of the same products abroad by using the above optimum preparation conditions. The microfiber glass mat was prepared by the flame method with spraying binder at the same time. The preparation condition of microfiber glass mat was mainly investigated and optimized. Shing currency was 787±5mA. The optimal added content of phenolic resin adhesive and water resistant agent was 7% and 0.4%, respectively. Through utilizing the optimal conditions, the prepared microfiber glass mat obtained more excellent mechanical properties than the overseas products.
Simulation and Calculation of Interior Ballistic of A Large Caliber Artillery
Authors: Wang Dan-Yu , Nan Feng-Qiang , Du Ping , Zhao Xin-Min , Wang Zheng-Lun
Published: January 2020

Based on the classical interior ballistic model, the model is improved according to the actual situation. Relying on the newly established model, the related software is compiled. The maximum bore pressure, muzzle velocity and detonation temperature of a 155mm caliber gun are simulated by using relevant software. The maximum bore pressure is 338.2748 MPa, muzzle velocity is 855.1096 m/s and detonation temperature is 3468.402 K. After comparing the calculated results with the experimental data, it is found that the software is more practical and can be applied in engineering practice.
Study on environment-friendly passivation for hot-dip galvanized steel with high corrosion resistance
Authors: Dong Xueqiang , Guo Taixiong , Zhouyilin
Published: January 2020

In order to improve the corrosion resistance of hot-dip galvanized steel, experimental study developed a new trivalent chromium passivation film with high corrosion resistant. The preparation method of passivation coating with high corrosion resistant was that the CrO3 was reduced to trivalent chromium by sufficient organic compound with reduction, then added colloidal SiO2, the matter containing radical phosphate and other substances after reaction completely. The passivation coating did not contain hexavalent chromium, and can meet the requirement of RoHS directive, so the film on hot-dip galvanized steel after passivation was environment-friendly. After coated on the hot-dip galvanized steel, the coating could be fast drying at 100 °C about 10s to 20s. The film was uniform, and did not appear floating, falling and other abnormal phenomenon, so that the passivation coating had good coating performance. The passivation reaction of the new trivalent chromium coating on the hot-dip galvanized steel was compound processes of electrochemical reaction, precipitation reaction and physical deposition. The passivation film produced no corrosion basically after 120h in the neutral salt spray test according to the Chinese national standards GB/T10125 and corroded area is less than 5% after 216 h, thus the corrosion resistance of the passivation film was excellent. In addition, the film has excellent heat resistance and fingerprint resistance, so it can meet the requirements of the user.
Study on the Film of Ti-Si-C-O Oxides and Its Application in Memristor
Authors: Zhao Xin , Yuan Yuhan , Liu Cheng , Li Dongyang , Li Wei
Published: January 2020

The thin films of Ti-Si-C-O oxides are fabricated via direct-current magnetron co-sputtering using a Ti3SiC2 target with oxygen (O2). The X-ray photoelectron spectroscopy is used to verified the composition of the Ti-Si-C-O thin films. A memristor is designed as the structure of Pt/TSCO/ITO/glass, and the I-V curves as well as the switching behaviors are studied for the first time. The results indicated that there appear typical pinched hysteresis I-V loops and continuous resistance changes under positive and negative sweeping bias, and that the device conductance can be modulated by consecutive potentiating and depressing programming. The carrier transport mechanism of the device is also investigated and it is found that the Ohmic connection is the leading factor in the linear low electric field region while Schottky emission in the non-liner high electric field region.
Research on dynamic inverse method of surrounding rock mechanical parameters of large underground caverns in excavation
Authors: Di Shengjie , Zhang Ying , Zhou Heng , Liu Jing
Published: January 2020

Rock mechanical parameters are important factors to affect the stability of surrounding rock in underground engineering. With the development of underground cavern excavation progress, the mechanical parameters of rock mass will change significantly. In order to reflect the change of parameters during excavation in real time based on uniform design and optimization algorithm technology, dynamic inverse method of surrounding rock parameters during excavation of underground caverns is carried out. Considering the location, elevation and period of excavation, the parameters inversion are divided into excavation sections and staged. Verified by actual engineering, the calculated displacement values of the inversion agree well with the measured.
Study on a New Measurement Method of Small Polarization Rotation Using the Common-Path Heterodyne Interferometry and a Half-Wave Plate
Authors: Chiu Ming-Hung , Tsai Chih-Ting
Published: January 2020

This thesis proposes a novel method for small polarization rotation measurement using a half-wave plate and a high-stability common-path heterodyne interferometry. The phase with azimuth angle 22.5° of a half-wave plate has a distinct change resulting from the small polarization rotation of the incident light. The optical rotation properties of a material, such as glucose solution, can be determined in this phase from the concentration of the solution. Finally, the phase can be measured using a lock-in amplifier, and the relevant formula between the glucose concentration and the polarization rotation can also be identified with a recording table.
Automatic Classification for Ground Targets under Complex Background Based on Bag of Words Model
Authors: Jin Wei , Feng Yunsong
Published: January 2020

In order to improve the performance of the automatic classifier for ground targets under complex background, a new classifier which was based on bag of words model and support vector machine (SVM) was build. Firstly, the keypoints of a target image were extracted into vectors by using Scale-Invariant Feature Transform algorithm, and vectors which were extracted from all trained images were merged into large vectors. Secondly, the large vectors were clustered into small vectors which included K vectors by using K-means clustering algorithm. To analyze how different values of K affected the classifying results, K was set to several different numbers. Thirdly, vectors which were extracted from all trained images were classified, and K-dimensional numerical vectors were obtained. Finally, the classifier was build with SVM algorithm, and the K-dimensional vectors were as input features of the classifier. The training images were randomly chosen from 90% of images dataset which included missile launch vehicles and tanks, and the rest 10% were as the testing images. The trained classifier is tested, and the f1-score value is 0.79. The results show that the new classifier can perform well.
A High-Efficiency and Real-Time Method for Quality Evaluation of PPG Signals
Authors: Li Hongxing , Huang Shizhao
Published: January 2020

The pulse oximeter (POM) is a device for real-time detection of HR and SpO2 based on PPG (Photo Plethyamo Graphy) signals, and its detection accuracy varies with diverse interferences. Therefore, it is presented in the paper a method for quality evaluation of PPG signals to detect wavebands of interference signals. Firstly, features of PPG signals are acquired by slope weighted sum function (SSF). Then, the normalized cross-correlation coefficient of each signal and its reference signal is calculated. Finally, signal quality index (SQI) is calculated based on nonlinear scaling function. In the research, 20 PPG signals with 1469 beats are chosen from the CB database to make the experiments of signal quality evaluation. The experimental results show that the method included can effectively identify useful signals from the mixed signals. The sensitivity and positive prediction value are 94.66% and 96.78%, respectively. Consequently, the method proposed has high recognition accuracy with key significance in clinical applications.
Properties of mode-locked ultrafast fiber lasers
Authors: Jia Youwen
Published: January 2020

Lasers, including solid-state lasers, fiber lasers and ultrafast fiber laser, are critical to our daily lives. Different kinds of laser have their own advantages and disadvantages. For solid-state lasers, they can generate short duration, high energy pulses but are difficult to maintain and expensive. Fiber lasers, which are compact, low-price, high-efficiency, can provide a novel solution to these issues. Here, we illustrate the theory and main features of the most important ultrafast fiber laser designs: soliton laser, dispersion-management soliton, dissipative soliton and Mamyshev oscillator. At last, we focus primarily on the promising future of the ultra-fast fiber lasers.
Preparation and Electrochemical Properties of LiMnPO4 Cathode Material with Controllable Morphology
Authors: Wang Zhongxu , Li Tingting
Published: January 2020

The morphology of particles was a really vital parameter influencing the electrochemical properties of LiMnPO4 based cathode materials. In this work, nano-sized LiMnPO4 with various kinds of morphology were prepared by solvothermal method. Then the phase structure, micro morphology and electrochemical properties were deeply analyzed by using XRD, SEM, electrochemical workstation and battery test system. The results indicated that obtained samples with porous and spindle-shaped powders show the best electrochemical properties, contributing to the decrease of Li+ diffusion coefficient and enhancement of wetting properties between the active powders and the electrolyte.
Fourier single-pixel imaging based on edge attenuation technique
Authors: Hu Yang-Di , Cheng Zheng-Dong , Liang Zhen-Yu , Xiang-Zhai  , Zhe-Wang
Published: January 2020

Fourier single-pixel imaging has been widely concerned with its real-time and high quality. However, DMD (Digital Micromirror Array) as an illumination source cannot produce a continuous gray level of the Fourier basis pattern. Therefore, the inevitable error is produced. This paper proposes a halftone technique based on edge attenuation, which can be applied to the Fourier basis pattern generation method on DMD without loss of resolution, and compared with the traditional methods, the invention solves the problem that the traditional methods has a single scanning direction and accumulated errors, finally; we improve the image quality.
Data Augmentation Based on Wasserstein Generative Adversarial Nets Under Few Samples
Authors: Jiang Yuchen , Zhu Bin , Ma Qi
Published: January 2020

Aiming at the problem of low accuracy of image classification under the condition of few samples, an improved method based on Wasserstein Generative Adversarial Nets is proposed. The small data sets are augmented by generating target samples through minimax game between the generator and the discriminator. Firstly, label information is introduced into the network to save the cost of manual labeling for the generated images, and then classifier loss is introduced to further improve the quality of generated images, and the classification accuracy is improved after expanding the data set.
Study on factors affecting the mechanical properties of dry mixing CDG based geopolymer
Authors: Zha Xiaoxiong , Wang Kai , Zhu Jiayuan
Published: January 2020

Cement is the main material for the construction industry. But it produces a large amount of greenhouse gases and consumes a lot of resources. As a new type of green cementitious material, geopolymer materials can replace cement. In order to simplify the preparation process of the geopolymer material, dry-mixing CDG geopolymer materials are prepared by using a dry mixing process technique, using a solid activator material, mixing the dry materials, and adding water to the mixture. In this paper, the completely decomposed granite (CDG) and slag are used as the main cementitious materials, and the geopolymer paste and concrete are prepared by the action of alkaline activator, and the systematic study on the mechanical properties of this new geopolymer material has been carried out.
Prediction method of coal slagging property in layer-fired boiler
Authors: Zhao Wang , Song-song Zhang , Li Guo , Guo-li Qi
Published: January 2020

In this article, different coal samples are selected and their physicochemical properties are analyzed. Study and comprehensively analyze various factors affecting slagging. Prediction of coal slagging properties using 12 influencing factors, include: softening temperature, the difference between deformation temperature and flow temperature, characteristic of char residue, sodium oxide content, silicon ratio, silica-alumina ratio, iron-calcium ratio, acid-base oxide ratio, sulfur slagging index, contamination index, chlorine content, inorganic mineral content. The fuzzy clustering analysis method was used to classify and quantify all the influencing factors, and the coal slagging prediction method of layer fired boiler was proposed and verified by application.
Uncertainty Research of Particles Concentration Measurement in Continuous Emission Monitoring System of Thermal Power Plants
Authors: Liang Tianqi , Zheng Tianlin , Zhang Guangxue , Ma Luyao , Xu Hong
Published: January 2020

In order to monitor the reliability of the CEMS operation data of a thermal power plant in Hangzhou, the data of its operation process were collected. The components of uncertainty influencing on the particles concentration measurement, including zero drift, range drift, relative accuracy and measuring repeatability, were analyzed in the system. The confidence interval (2.80%) and the allowable interval (8.94%) were introduced to ensure the reliability of the system data. The result of evalution shows that the related expanded uncertainty of particles concentration measurement is 9.26% when coverage factor is k=2 and level of confidence is 95%. Measuring repeatability is the main factor affecting the uncertainty.
Discussion on Relevant Issues of Thermal performance test code for industrial boilers
Authors: Yongqiang Chang , Tiankui Li , Peng Li
Published: January 2020

In the study and application of GB/T 10180-2017 “Thermal performance test code for industrial boilers”, the author found some unreasonable or error-prone areas in the rules. In this paper, the value of boiler thermal efficiency, the test method of condensing boiler, the correction method of boiler thermal efficiency and the calculation of desulfurization thermal efficiency are discussed, and personal suggestions are put forward.
Effect of crack length on tip field of 304 stainless steel SCC
Authors: Yang Xu , Zhang Jianlong
Published: January 2020

Stress corrosion cracking (SCC) is one of the key issues affecting the long-term safe operation of high temperature pressure vessels and pipeline. In this paper, the effect of crack length on the SCC crack tip field of austenitic 304 stainless steel is studied by using a compact tensile specimen. Firstly, the finite element model of SCC crack tip creep is established by using ABAQUS, and the crack tip creep and creep to crack tip mechanics are analyzed. The influence of different crack lengths on crack tip creep and creep rate was studied. It can be obtained by numerical simulation analysis software. The high creep variable area is mainly concentrated in the near crack tip region. The crack length has a great influence on the SCC crack tip creep field. With the continuous expansion of the austenitic 304 stainless steel crack, crack tip creep variables and creep rates are also increasing. It provides a theoretical reference for the safety evaluation and analysis of high temperature pressure vessels and pipelines.
Study on Separation Efficiency of Cyclone Separator for 75t/h Circulating Fluidized Bed Boiler
Authors: Wang Hai
Published: January 2020

Taking a 75t/h circulating fluidized bed boiler cyclone separator in a boiler manufacturing plant as the research object, this study uses FLUENT fluid calculation software and the balanced orbit and dwell time model to analyze the influence of the particle trajectory tracking, exhausting pipe length and pipe diameter on the separation efficiency The calculation results show that when the relative diameter is equal to 0.3∼0.5, the separation efficiency is already high. If the diameter of the core tube is reduced, the separation efficiency is not improved much. However, this will lead to a sharp increase in pressure loss; The increase of the powder concentration is markedly increased; the larger the particle size is, the higher the separation efficiency is. The separation efficiency is obviously improved after the particle size is larger than 30 μm. The separation efficiency is already high after the particle size is larger than 80 μm, and the increase of the particle size is not significant.
Boiler Thermal Efficiency Test System Based on NB-IoT Technology
Authors: Chen Zhigang , Xu Chongtao , Gao Shuai
Published: January 2020

This paper combines the wireless NB-IoT technology with the traditional boiler thermal efficiency test, and uses LabVIEW to develop a test analysis system. By installing the data export module and the transmission module together on the existing equipment to perform wireless and digital upgrade of the detection equipment, the purpose of improving the automation degree of the thermal efficiency test is achieved, thereby reducing the number of test staff on site. At the same time, it will avoid the dust and high temperature danger that the staff will encounter on site. The complex boiler thermal efficiency calculation formula is simplified according to the wireless, real-time and accurate needs of the boiler thermal efficiency test. A formula for calculating the enthalpy value that satisfies the requirements of online testing, a formula for the heat loss of the incomplete combustion of the gas, and a formula for fitting the ash combustibles are proposed.
Research on Low Temperature Condensation of Flue Gas from Gas Industrial Boiler
Authors: Ji-Ming Yu , Juan Li , Jian Guan
Published: January 2020

The paper analyzed the heat transfer in the condensing section of condensing gas industrial boiler. As to the operation of boiler, the field test of the flue gas condensing section was carried out where the field test data was compared with the theoretical values to verify the calculation formula of the convective exothermic coefficient of the condensing section in the condensing boiler’s spiral rib.
Energy conservation certification for coal layer-combustion industrial boiler
Authors: Liu Xuemin , Yu Jiming , Zhang Songsong , Zhao Lihua
Published: January 2020

The effect of boiler load on main operation parameters and the boiler efficiency were investigated, and the thermal efficiency distribution of nearly 300 coal-fired boilers was further analyzed. The results show that the exit gas temperature decreases as the boiler load decreases, while the unburned carbon contents in ash and slag, and CO content in flue gas usually increase. Correspondingly, the loss due to exit gas decreases, and the loss due to unburned solids usually increases. The loss due to surface radiation and convection increases. Taking into account changes of all the losses, the boiler efficiency decreases at lower loads. With reference to TSG G0002, Technical Specification for Energy Conservation Certification of Coal Layer-Combustion Industrial Boiler under off-Design Conditions has been drafted and the evaluating values of energy conservation for products have been proposed, including boiler efficiency under different test loads and CO concentration in flue gas. The target efficiency values vary according to the boiler capacity and fuel type. The CO concentration value is a limit that can be achieved by most boilers.
Apparatus for investigation of heat transfer to H2O/CO2 mixtures in both near-critical and supercritical regions
Authors: Wu Haomin , Zhang Hanlin , Li Sha , Liu Dong , Li Qiang
Published: January 2020

Supercritical H2O/CO2 mixtures are the working fluid in a novel power generation system with coal gasified in supercritical water, so their heat transfer behaviors are important to design heat transfer devices. However, heat transfer to supercritical mixtures has received few attention. Here, we designed and established an apparatus to measure the forced convection coefficients and constant pressure heat capacities of H2O/CO2 mixtures in both near-critical and supercritical regions. The highest mixture temperature is designed to be 873 K with the highest pressure of 25 MPa and with the CO2 mass fraction up to 25%. Results show that our apparatus is stable in both near-critical and supercritical regions, which is challenging for high-temperature and high-pressure experiments. Furthermore, our apparatus has lower uncertainties than those in previous studies.
Effect of Surface State on Acid Rain Corrosion Resistance of T6 6005A Aluminum Alloy by BT-FSW Joint
Authors: Qin Zhiheng , Xu Hongji
Published: January 2020

The test sample was 5 mm thick artificial aging 6005A aluminium alloy profile, which was butted by BT-FSW. This work aimed to analyse the effect of surface state on corrosion resistance of welded joints in acid rain environment based on acetate ssalt spray test (CASS), polarization curve and EIS impedance test, combined with SEM scanning and EDS energy spectrum. The results showed that the corrosion rate of pre-welded polished joints was high at the initial stage of salt spray corrosion, and the corrosion rate of both joints were equal at the later stage of corrosion, higher than that of base metal. The best preservation of corrosion morphology was THAZ, followed by nugget zone and HAZ, and the pitting degree of base metal was the most serious. The polarization curves of the polished joints before 30 min corrosion were located at the lower right of the image, and its self-corrosion current density in the nugget zone showed the worst corrosion resistance. The corrosion resistance of the pre-welded polished joint increased after 336 hours of corrosion, the corrosion breakdown potential and self-corrosion current were not significantly different from those of the unpolished joints. The fitting curves of the two kinds of joints had similar dual capacitance arc resistance characteristics and the impedance parameters in EIS, and the electrochemical corrosion resistance of the two joints were weaker than that of the base metal.
A Study on the Change of Manufacturing Design Process due to the Development of A.I Design and 3D Printing
Authors: Hyunjin Chun
Published: January 2020

The fourth industrial revolution brought about changes in various fields. The speed of the fourth industrial revolution will proceed faster than the previous ones. It is a new revolution in which new technologies are integrated. So the convergence of new technologies in the fourth industrial revolution will affect many areas. In particular, new technologies such as artificial intelligence and 3D printing technology are being used in the manufacturing industry. The fourth industrial revolution will change the manufacturing design process in the future. Predicted changes are as follows: First, existing management processes are divided into planning, design and manufacturing processes. The collection and analysis of many data are important in the planning process. This planning phase enabled data collection, processing and management through cloud computing and big data technologies. Based on these plans, artificial intelligence can produce thousands of design results. Next, based on the design plan, products can be produced in 3D printing. As such, the manufacturing process has been very simplified by 3D printing. The study can offer some solutions for social changing problems by predicting the future of manufacturing. And the results of the study can be used as a research base in the manufacturing design sector using artificial intelligence and 3D printing.
Application of Reverse Engineering on Spacecraft Assembly Process Simulation
Authors: Yiliu Xu , Chunsheng Yang , Kai Xu , Wei Wang , Xing Fan , Jun Hou
Published: January 2020

This paper proposes a new process that assembly simulation with 3-D model which obtained from product to improve the reliability of spacecraft assembly. 3-D model of the satellite camera which obtained by reverse engineering was used in DELMIA virtual assembly simulation. The point cloud date of the model was scanned by laser radar, and the scanning accuracy is 0.3mm. To get more accurate model data, firstly it’s necessary to remove noise data by the method of HCI and curve inspect; then, min-distance method was used to streamline the point data, and repair the data by complementary surface; finally, reconstruct the model by the triangular Bezier surface. Because the model obtained by RE is more exact than the ordinary model, the virtual assembly simulation is more useful. During the period of installing the camera, as the simulation, the risk was avoided and the process was successful.
Experimental studies on caffeine mediated synthesis of hydroxyapatite nanorods and their characterization
Authors: Subramanian R , Murugan P , Chinnadurai G , Ponmurugan K , Al-Dhabi Naif Abdullah
Published: January 2020

Hydroxyapatite nanorods (HA) were fabricated using caffeine as a modifier at room temperature. Various concentrations of caffeine were utilized to synthesize the HA nanoparticles to analyze its effect on size, shape and morphology. The formation of phosphate ion was confirmed by Fourier Transform spectrophotometer (FTIR). Crystalline structure and phase of the nanoparticles was confirmed by x-ray diffraction study (XRD). The formation of HA nanorods with diversified morphology was confirmed by Transmission Electron Microscope (TEM) images. The results acquired in this study reveals that the HA nanoparticles synthesized using caffeine are uniform and evenly scattered nanorods. The average size of the nanorods obtained from the XRD study was in the range of 20–30 nm. The TEM and SAED investigation revealed the shape, morphology and arrangement of HA nanorods with higher crystallinity. This investigation claims that caffeine is a natural modifier to produce HA nanorods.
Enhanced photocatalytic activity of Cuprous Oxide nanoparticles for malachite green degradation under the visible light radiation
Authors: Muthukumaran M , Gnanamoorthy G , Varun Prasath P , Abinaya M , Dhinagaran G , Sagadevan Suresh , Mohammad Faruq , Oh Won Chun , Venkatachalam K
Published: January 2020

Photocatalysis provides excellent potentials for the complete removal of organic pollutants in environmentally friendly ways and sustainable means of technology. It has been noted that under UV-visible light irradiation, nanostructured semiconductor metal oxides photocatalysts can degrade different organic pollutants. Taking into consideration of the photocatalytic activity, the present study deals with the synthesis of cuprous oxide (Cu2O) nanoparticles (NPs) by the sonochemical method and characterized for their physicochemical, optical, and photocatalytic properties. The powdered X-ray diffraction (XRD) analysis confirmed for the cubic phase crystalline structure while the Field emission scanning electron microscopy (SEM) supported for the icosahedron morphology. The bandgap of the synthesized Cu2O NPs was found to be 2.26 eV, which is the suitable bandgap energy so as to achieve the enhanced photocatalytic degradation efficiency. On testing for the degradation of Malachite green (MG) as a model pollutant, the synthesized Cu2O NPs demonstrated a high degradation efficiency under visible light irradiation. The observed results suggest that the synthesized Cu2O NPs are attractive photocatalysts for the degradation of toxic organic wastes in the water under visible light. Further investigation confirmed for the photocatalytic reduction of 4-nitrophenol (4-NP) into 4-aminophenol (4-AP) under aqueous conditions with visible light.
Photocatalytic activity of CuInS2 nanoparticles synthesized via a simple and rapid microwave heating process
Authors: Chumha Nawapong , Pudkon Watcharapong , Chachvalvutikul Auttaphon , Luangwanta Tawanwit , Randorn Chamnan , Inceesungvorn Burapat , Ngamjarurojana Athipong , Kaowphong Sulawan
Published: January 2020

In this research, visible–light photocatalytic activities of CuInS2 nanoparticles for degradation of three organic dyes (rhodamine B; RhB, methylene blue; MB, and methyl orange; MO) were investigated. The CuInS2 nanoparticles were synthesized by a simple and rapid microwave heating process using sodium sulfide as a sulfur source and then characterized by x–ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET), and UV–vis diffuse reflectance spectroscopy (UV–vis DRS) techniques. The synthesized CuInS2 nanoparticles exhibited excellent photocatalytic degradation activity to the cationic dyes (RhB and MB) when compared with that of anionic dye (MO). Zeta potential of the CuInS2 photocatalyst was measured to elucidate the adsorption ability toward dye molecules. A possible photocatalytic degradation mechanism was proposed based on active species quenching experiments and Mott–Schottky analysis.
Effect of SiC layer on microwave absorption properties of novel three-dimensional interconnected SiC foam with double-layer hollow skeleton
Authors: Li Binbin , Mao Bangxiao , He Tao , Wang Xingbang , Huang Haiquan
Published: January 2020

To design a lightweight and high-performance absorber, this work introduced a novel three-dimensional interconnected SiC foam with double-layer hollow skeleton (3D-ISF), which was prepared by depositing SiC, pyrolytic carbon, and SiC layer on interconnected carbon foam, followed by oxidation of carbon. SEM results showed the interconnected hollow structure had been successfully synthesized, which was beneficial for microwave absorbing efficiency, and numerous columnar SiC defects were observed and played a critical role in the microwave absorption properties. The electromagnetic performances of 3D-ISF-I and 3D-ISF-II were investigated in depth. With the increase of thickness of SiC layer, 3D-ISF-II exhibited a better microwave absorption property, which could be ascribed to the higher impedance matching ratio (Z

r
) and attenuation constant (α). The optimum reflection loss value of 3D-ISF-II could reach −45.649 dB while that of 3D-ISF-I was just −32.070 dB. There is no doubt that the prepared materials have tunable microwave absorbing properties, which can promote the development of SiC-based absorbing materials to a certain extent. Finally, it was confirmed that the Z

r
played a dominant role in 3D-ISF, which provided practical guidance for the design of porous materials.