bluuebunny/crossref_metadata_2025 huggingface dataset:
Space group and morphology evolution of nanosized Nd(x)Sr(1-x)MnO3 manganite
Authors: Dharmayanti A M R , Munazat D R , Razaq D S , Kurniawan B , Mustaghfiroh Q , Nanto D , Handoko D
Published: March 2021

Polycrystalline series sample of Nd(x)Sr(1-x)MnO3 (x = 0.3; 0.7 and 0.9) has been prepared with sol-gel method. Refinement result from X-ray diffractometer shows that the sample are crystallize in the same orthorhombic structure with different space group of Imma and Pnma. Scanning Electron Microscope result also indicated that the different amount of substitution modified the grain size and both particle and crystallite size. After all, Nd0.7Sr0.3MnO3 has the largest cell volume followed by the largest grain and crystallite size compared to other two samples. Therefore, each different amount of substitution into the sample will give different impact and further investigation were needed to explore its relation to the physical properties.
Effect Of Mn On Structure And Corrosion Properties Of Co-Cr-Mo Alloys in Simulated Body Solutions
Authors: Qonita Aliya , Eka Perkasa Daniel , Soegijono Bambang
Published: March 2021

Metal alloys applied as biomedical materials have been developed for decade, due to the need for devices implanted into the human body. One of them is a cobalt-based alloy which commonly used as an orthopedic implant for total hip replacement. The biocompatibility properties of CoCrMo alloys make these alloys superior to corrosive resistance when making direct contact with the biological environment of the body where Simulated Body Fluid (SBF) solution is a solution often used to test its compatibility. The presence of manganese elements in CoCrMo Alloy and influence of heat treatment at temperature 700 oC for 65 hours were characterized by using X ray diffraction and Potentiostat. The structure and corrosion behavior in Simulated Body Fluid were discussed. The results show different crystal parameter and corrosion behavior observed. It concludes that, heat treatment and the presence of Mn affect the signicantly on the properties of CoCrMo Alloy.
Preliminary Study on the Use of Optical Fiber to Detect Borax Content in Meat
Authors: Yunianto Mohtar , Putri Andaresta Dita , Anwar Fuad , Endah Saraswati Teguh
Published: March 2021

A preliminary study has been conducted to detect the presence of borax in meat using a optical fiber sensor. The study was conducted in 2 stages, the first stage was a test using a UV-Vis spectrometer which was used as reference data to test the presence of borax in meat with variations in the borax mass of 0.1 gr, 0.2 gr and 0.3 gr mixed with each 40 gr of beef, while the next stage is to use an optical fiber sensor that has been made where the results of testing are compared with the results of the first stage. The results obtained in the initial stage are more and more borax content in the meat showing the absorbance value increases at a wavelength of 419 nm with an R2 value of 0.93. In the second stage using an optical fiber sensor, the results of transmittance values obtained at 419 nm wavelength decreased linearly with R2 values of 0.99, the transmittance value is inversely proportional to the absorbance value. This shows that a fiber optic sensor made has the potential to be used as detection for borax content in meat.
DECY-13 cyclotron equilibrium orbit verification using CYCLONE
Authors: Mulyani E , Taufik  , Darmawan R S , Kudus I A , Diah F I
Published: March 2021

A cyclotron is a machine that accelerates a charged particle in a circular trajectory using electric and magnetic fields. The technical development of 13 MeV cyclotron in PSTA (Pusat Sains dan Teknologi Akselerator) BATAN was started in 2010 which eventually will be used for radioisotope production. A cyclotron consists of various technologies such as an electromagnetic, RF (Radio Frequency), ion source, and vacuum systems. Among them, the electromagnetic creates a magnetic field for particles to accelerate in a stable circular orbit. A particle within a uniform magnetic field moves along a closed trajectory, and that is called an equilibrium orbit. The stability of particle acceleration refers to the movement along the equilibrium orbit with oscillation. This paper deals with the equilibrium orbit verification using CYCLONE. We calculated and analyzed the magnetic and electric fields using Opera, then used them as input data in CYCLONE. The CYCLONE analysis provides several beam parameters such as beam energy, tune diagram, and beam trajectory. The analysis result shows that the beam was accelerated until the desired energy (13 MeV).
Mapping and Analysis Burned Area Based on LANDSAT 8 OLI/TIRS and Hotspots Data in Palangkaraya of Central Kalimantan Province - Indonesia
Authors: Eko Cahyono Bowo , Fibyana Vica , Tjahjo Nugroho Agung , Subekti Agus
Published: March 2021

Indonesia experienced with big forest fire every year especially within dry season. Palangkaraya City of Central Kalimantan province is the most prone area with fire. It was reported that Palangkaraya had the highest risk of fire in 2019 which caused smog that disrupts people breathing and their daily activities. Indonesian government is paying a great attention to manage and suppress the fire. People are encouraged to provide information of burning location, responsible company and burned area in the incident. This study determined burned area in Palangkaraya using Normalized Burned Ratio (NBR) method and the results were validated with hotspots data acquired from LAPAN website. The results showed that 64.24% burned area is classified as low severity and only 1.04% of burned area is classified as high severity. The remaining area with 31.84% categorized in moderate low severity and 2.88% categorized in moderate high severity. The validation result showed that 100%of burned area is confirmed valid with the occurring hotspots.
Railway Vibration Level in Semarang City
Authors: Margiantono A. , Setijo H. , Setiawati E.
Published: March 2021

Increased train traffic in the city of Semarang caused an increase in vibration exposure to residents and buildings that are around the railroad. Train vibrations have a large influence on comfort, human health and building structures. The location of this research data collection in three places, namely Bulu Lor Settlement, Tawang Station area and Tlogomulyo Village, the reason the location was chosen is because the route is the busiest route in the city of Semarang so it has a high vibration level. Vibration intersection (A) and vibration velocity (v) are measured when a train is passing using a Vibration level meter. The results showed that the Bulu Lor settlement at a distance of 15m from the highest intersection of the axle road was 29.27 microns at a frequency of 12.5 Hz and the lowest was 4.45 microns at a frequency of 63 Hz. In the Tawang Station Area, the highest 25m distance is 20.38 microns at 12.5 Hz frequency and the lowest is 3.55 microns at 63Hz frequency, while in Tlogomulyo Kelurahan at 25m distance from the highest intersection of axles by 21.28 microns at 12, 5Hz and lowest 3.61 microns at 63Hz frequency. Referring to the results of this research, it can be concluded that all the values of the vibrational quantities are still below the standard level according to Kep-49 / MENLH / 11/1996, so that the vibrations of the passing trains do not disturb and do not damage the buildings at the three points of the research location.
Physical deterioration of soil and rice productivity in rural Java
Authors: Irawan S , Antriyandarti E
Published: March 2021

Soil degradation is one of the world’s most serious ecological and environmental problems affected agricultural productions. The agricultural sector defines land degradation as a process of decreasing land productivity that is temporary or permanent, characterized by a decrease in physical, chemical, and biological properties. This study aims to investigate the impact physical deterioration of which occurs in the form of structure fertilizer application on rice productivity. This study applied Autoregressive model to analyse the primary data collected from 4 main rice producer areas in Central Java and East Java, namely Cilacap, Grobogan, Lamongan and Jember. The results show that previous chemical fertilizer use has negative impacts on rice productivity. Inorganic chemical fertilizers have an important role in increasing productivity, but at the same time the uncontrolled use of it is one of the causes of the decline in the quality of biological, physical, and chemical fertility of the soil.
Quantitative Assessment of NPP Changes in the Yellow River Source Area from 2001 to 2017
Authors: Rong Tang , Long Lin Hui
Published: March 2021

It is of great significance to quantitatively evaluate the ecological degradation and restoration of the Yellow River source area from 2001 to 2017. Net primary productivity (NPP) is the core indicator used to indicate the health of terrestrial ecosystems. Based on the improved CASA (Carnegie-Ames-Stanford Approach) model and MOD17A3 NPP products, 174 measured sample sites were used to validate the NPP simulation results, select the model with higher accuracy as the actual NPP simulation, and using Theil-Sen median trend analysis and Mann-Kendall test to investigate the dynamics of NPP changes. The results are as follows: (1) the accuracy of the CASA model is higher than that of the MOD17A3 NPP product, and it is more suitable for the simulation of the actual NPP in the source area of the Yellow River; (2) the Yellow River Source region has shown a fluctuating upward trend in net primary productivity over the past 17 years, with 50% of the region showing a slight improvement, 36% showing a significant improvement, 13% showing a slight decline, and only 1% showing a significant decline, the average annual growth rate of NPP is 2.6 g C/yr-1. Compared with 2001, the net primary productivity in 2017 increased by 5.24×1012g C.
Efficient PFOS decomposition in an alkaline ultrasonic system
Authors: Gu Yurong , Jiang Chengchun , Dong Zijun , Xiao Yating
Published: March 2021

Perfluorooctane sulfonate (PFOS) has attracted increasing attention due to its global distribution, high chemical stability and environmental persistence. An alkaline ultrasonic system was explored and used for PFOS decomposition in this study. kobs of PFOS decomposition in the investigated system was 0.0196 min−1, which was remarkably efficient than that in sole ultrasonic system. eaq
− induced reductive decomposition and pyrolysis decomposition based on the collapse of cavitation bubble were found to be two main reasons contributing to PFOS decomposition. PFOS decomposition kinetics was boosted by increasing alkaline dosage and reaction temperature, but suppressed when increasing initial PFOS concentration.
Experimental Research on Dust Concentration Distribution Characteristics of Blast Furnace Cast House
Authors: Tianying Wang , Jingling Yang , Xiaohua Zhu , Hui Wang
Published: March 2021

This paper compares the temperature and dust concentration distribution of blast furnace cast house under different dust removal design conditions and external climate conditions by means of on-site sampling, field measurement and data analysis. It is found that the post temperature in closed design of cast house is 2.4°C lower than that in open design, but the dust concentration of the post of open design is 0.139 mg/m3, which is 1/10 of that of the closed design. Therefore, the open design is recommended. Different climatic conditions also have influence. It is suggested to close the main wind direction doors and windows when the outside wind speed is high to avoid turbulence.
Discussion on Related Factors of Air Pollution Based on Automatic Monitoring Data of Air Quality
Authors: Xia Li , Maolin Deng
Published: March 2021

Air pollution seriously affects people’s production and life. In order to explore the main factors affecting the air quality of Zhangye and evaluate the air quality, based on the national air quality automatic monitoring data, first, PM2.5, carbon monoxide (CO), nitrogen dioxide (NO2), ozone (O3), and sulfur dioxide (SO2) are selected as the component factors of air pollution. Second, based on the fuzzy comprehensive evaluation method, the evaluation standard set and air quality pollution level are established. Finally, the time characteristics of each factor from 2016 to 2019 are analyzed. The results show that: the overall air quality of Zhangye is more serious in spring and winter, while it is more moderate in summer and autumn. PM 2.5 and O3 are the two key factors affecting its air quality; the air quality trend of Zhangye in recent years is good, and the overall air pollution level is below V2. The improvement of air quality depends on the effective control of all aspects, including human activities.
Research on environmental management of medical waste in the 14th Five-Year Plan
Authors: Shuangliu Liu , Liang Cheng , Zheng Zhang , Ya Tao , Mengyin Yao
Published: March 2021

Aiming to promote environmental management in the field of medical waste, based on the analysis of the current situation of national medical waste production and disposal, problems existing in the current system of concentrated disposal of medical wastes were identified, namely, the insufficient of centralized disposal capacity of medical waste in some areas, insufficient emergency disposal capacity reserve of medical waste, weakness of of medical waste supervision level and unperfect of technical standards. It is suggested to promote the environmental management of medical waste during the "14th Five-Year Plan" period by strengthening the centralized disposal capacity of medical waste in key cities, improving the disposal capacity of medical waste in rural and remote areas, speeding up the allocation of emergency disposal capacity of medical waste, and improving the environmental supervision capacity of medical waste.
Analysis of Temporal and Spatial Variation Characteristics of Air Quality in the Pearl River Delta during 2015-2019
Authors: Chuntao Huang , Qifeng Liao , Jifu Lu
Published: March 2021

Based on the history monitoring data of Air Quality Index (AQI) during 2015-2019, we conducted a contrastive analysis of the temporal and spatial variation characteristics of air quality in the Pearl River Delta. Results showed that the variation trends of AQI annual averages in the Pearl River Delta were basically the same. The AQI annual averages rose after decline and the variation curves were W-shaped. In the Pearl River Delta, Shenzhen and Huizhou enjoyed better air quality. In this region, AQI quarterly averages were high in autumn and winter but low in summer, and in a same year, the variation trends of the nine cities were basically the same. In autumn, the ozone concentration increased dramatically and therefore ozone became a major pollutant in ambient air. In winter, Guangzhou, Shenzhen and Dongguan saw a double-peak phenomenon in AQI hourly values, which rose at rush hours.
Index evaluation of overall stability of small-span steel plate bridge
Authors: Li Haoqi
Published: March 2021

Based on a 3×35m steel plate bridge of a highway project, a nonlinear entity model is established using finite element software, and the structure is evaluated with the stability safety factor as the evaluation index. Through the analysis of different parameters, some conclusions are drawn to satisfy the stability of the bridge structure.
A two-stage robust optimization framework for land-water-environment nexus management
Authors: Chen Rui , Xu Zhongwen
Published: March 2021

On the premise of rational utilization of soil and water resources, systematic engineering method is widely considered to balance agriculture and ecology. Regular planning is carried out by the authority based on historical data and future expectation, however, uncertain environment cannot be ignored. Hence, we propose an adjusted dynamic two-stage robust optimization framework to explore comprehensive managerial insights of irrigative areas and forest expansion. Dynamic planning is adopted to reflect the long-period planning, and two-stage is to differ “wait-and-see” decision from “right-and-now” decision. Considering the whole system’ benefit, economic and ecological benefits are maximized and water scarcity, water/soil erosion penalties are minimized. To solve the proposed two-stage robust model, we propose two structural properties to obtain the global solution. After transformation, a C&CG algorithm is designed to calculate the proposed model.
Temporal and Spatial Succession Law of Abor Diversity in Xiaoxing’an Mountains
Authors: Li Jialin , Yang Jiao , Sun XueWei , Luo Jincheng , Qiu Hongbin , Li Lan
Published: March 2021

The national forest nature reserve in the Xiaoxing’anling area was studied. Based on the diversity of α and β, three forest types of grassland, birch forest, and larch forest were analyzed. Based on the diversity law of latitude gradient, the nature reserve was discussed in forest type. A difference in a diversity of different forest types was succession changes. A method based on quantitative evaluation of species conservation value was constructed. The community structure and species composition of nature reserves were systematically analyzed, and the conservation value of species and the conservation value of rare and endangered species were scientifically evaluated. The results showed that the Shannon Wiener index and Margalef index of grassland, birch forest, and larch forest showed a decreasing trend with the increase of latitude. Compared with the other four latitudes, the grassland, birch forest and larch forest of Dazhanhe Nature Reserve showed a decreasing trend from the north to south Jaccard index and Sorenson index, and the Cody index showed an increasing trend. The Jaccard index and the Sorenson index have peaks in friendly areas, and the species similarity is high, indicating that the friendly areas may be the interlaced areas of Xiaoxing’anling. The Shannon Wiener index and the Margalef index of the nature reserve from the early stage of succession to the middle and late succession increased continuously, reaching the maximum in the middle and late stages, and began to decline in the later stage of succession, which is consistent with the mid-specie.
Effects of Different Pesticide Treatments on Soft Rot Control and Yield of Konjac
Authors: Jiang Xiong , Wang Zhengxiang , Yang Fuqing , Chen Zhizhou , Yang Sumian , Yan Zesheng , Qin Yaoguo
Published: March 2021

To screen pesticides with improved disease control and increase the yield of konjac plant, we grew one-year-old konjac corms, determined the field control effect, growth indicators, photosynthetic indicators, and yield of konjac plants, and compared the results with those obtained after treatments with three kinds of antibiotic pesticides, three kinds of copper fungicides, chloroisobromine cyanuric acid, bismerthiazol, and water (as control). The results showed that the soft rot incidences in konjac plants after treatment with several pesticides were significantly lower than that of the control (CK). The control effects of tetramycin, copper succinate, and chloroisobromine cyanuric acid were high, the growth status of the plants treated with cuprous oxide, tetramycin, and copper succinate improved; the net photosynthetic rates of each pesticide treatment showed no significant difference from that of the CK, and the yield was the highest with copper succinate and tetramycin. This study demonstrated that certain copper fungicides or antibiotic pesticides can be used for the control of konjac soft rot, but their effects are different. The comprehensive comparison suggests that the effects of copper succinate and tetramycin are the best for the disease control and yield increase of konjac.
Exploration on key factors for overall migration into olive oil of food-contact silicone
Authors: Hu Jinmei
Published: March 2021

To ensure the accuracy of the overall migration into olive oil of high risk food-contact silicone products, the key factors of the test method on the base of EN1186-1 &2 were analyzed and discussed. Two sample conditioning methods for the silicone products were compared, and the extraction times for olive oil in the samples were investigated, as well as the change trend of the actual temperature of olive oil at the set temperature. Using calcium chloride dryer conditioning method can achieve the same effect of constant temperature and humidity method, and can significantly reduce the conditioning time. For silicone products that are easily absorbed oil, the olive oil in the sample should be extracted at least twice. The temperature of the oven should be increased appropriately to meet the requirements of the temperature of olive oil. The water conditioning of samples, the extraction times of olive oil and the preheating temperature of olive oil are the key factors for olive oil overall migration of food-contact silicone, which can provide a reference for testing workers of food-contact materials.
Research on self-insulating block composed of ground rice husk and recycled aggregate in severe cold area
Authors: Shi Daquan , Fang Guangxiu , Li Pu , Yang Xu , Wu Xuanru
Published: March 2021

Aiming at severe cold areas, this paper replaces 5% cement and 30% natural gravel with the same amount of ground rice husks and recycled aggregates respectively, and designs a new self-insulating block structure model compared with traditional blocks. This new block is easy to assemble, short construction period and good seismic performance. The 28d splitting strength of concrete and 28d compressive strength of blocks are determined. The results showed that this mate is better than the cracking strength of the block that can act as a MU10 non-load-bearing wall, and the standard test piece is better than ordinary concrete.
Study on relationship between underlying surface of typical warping dam and erosion and sediment yield
Authors: Li Ma , YongXin Ni , XiZhi Lv , QiuFen Zhang , Li Li , LinNan Liu
Published: March 2021

Under the condition of rainstorm, the underlying surface is an important factor of erosion and sediment yield, and an important embodiment of the process of soil erosion and the law of sediment deposition. This paper analyzes the soil erosion of warping dams with different underlying surface characteristics based on the data of typical warping dams, such as sedimentation amount, sediment retention modulus and underlying surface. The results show that: (1) the average slope of dam55, dam97 and dam011 is 27.55°, 30.79° and 34.68° respectively, and the erosion modulus is 11020t/km2, 15204 t/km2 and 22579 t/km2 respectively; the average slope of dam55, dam97 and dam011 is positively correlated with the erosion modulus, and the correlation coefficient is 0.9889. (2) The sedimentation depth and erosion modulus of dam011 are significantly higher than those of dam55 and dam97. Under the condition of rainstorm, the average slope of watershed is an important factor of soil erosion, which can better reflect and predict the comprehensive intensity of soil erosion.
Mathematical model-based study of Scottish herring and mackerel migration
Authors: Yang Zhenzhen , Yue Jiaxin , Yu Yadan , Zhang Yuehua , Li Lan
Published: March 2021

The global sea temperature continues to rise and reaches a new high in 2019. This phenomenon will force the migration of Scottish herring and mackerel to higher latitudes and severely inhibit the development of small-scale Scottish fishing companies. This paper establishes a grey prediction model, a regression analysis prediction model and a fuzzy comprehensive evaluation model to explore the migration locations of herring and mackerel in the next 50 years, and to formulate appropriate business strategies for small-scale Scottish fishing companies. The model results show that in the next 50 years, herring and mackerel will migrate to Greenland and Norwegian waters, and will migrate out of the fishing range of small fishing companies from 2046 to 2053. Therefore, reducing labour costs is the most appropriate business strategy.
Synthesis and Properties of Hydrazine Picrate
Authors: Mu Xiaogang , Liu Bo , Li Zhaoxiang , Yang Jingjing
Published: March 2021

Picric acid was reacted with liquid propellant anhydrous hydrazine to synthesize anhydrous hydrazine picrate. Its structure was characterized by elemental analysis, infrared spectrum analysis, nuclear magnetic resonance, and its thermal decomposition performance was analyzed by TG-DTG and DSC. The thermal decomposition of anhydrous hydrazine picrate was studied by using Kissinger method and its activation energy was calculated. The critical temperature of thermal explosion was calculated by using the characteristic data of non-isothermal DSC curve. The results shows that the thermal decomposition of anhydrous hydrazide is mainly between 179.8∼200.9°C, the decomposition process is exothermic reaction, the melting point is about 140°C, the non-isothermal kinetic equation is ln(β/T
p

2
)=-17652 (1/T
p)+28.009, the activation energy of thermal decomposition is E=146.76kJ/mol, pre-exponential factor lnA=30.34, and the critical temperature of thermal explosion T
b=175.3°C. Anhydrous hydrazine picrate has the characteristics of simple synthesis, rapid reaction and good thermal stability. It provides a new way for the disposal and reuse of anhydrous hydrazine.
Multi-Objective Sustainable Planning of Chemical Production Chains
Authors: Zhang Zetian , Liu Zhenghan , Jia Xiaoping
Published: March 2021

Sound management of chemicals is one of key contributors for achieving of the Sustainable Development Goals. The aim of this work is developing a multi-objective planning framework on the early planning and decision-making for chemical production processes, in order to obtain the maximum economic benefits, minimize the risk of possible chemical accidents to people, and minimize the environmental risk of production routes. GM (1, 1) model was established to predict the price trend and demand change of chemical products from 2020 to 2030. Combining three objective functions with the production chain constraints, a mixed integer linear programming model is developed. Polyvinyl Chloride production chains are taken as an example.
Status and Future Development Prospects of CSP
Authors: Ruidong Wang , Jun MA
Published: March 2021

As a type of energy which is clean, renewable and pollution-free, solar energy possesses a large amount of reserves but its energy flux density is low. Concentrating Solar Power (CSP) technology is an effective way of utilizing solar energy, which can be a replacement of thermal power. By ways of realizing peak load regulation in the grid, and greatly improving the transmission capacity of the power grid, CSP can provide a solution to the problem of abandoning wind and light in northwest China, and promote the sustainable development of clean energy in the whole country. In this paper, the key technologies of CSP are reviewed, and the present developing situations at home and abroad are summarized. In addition, the problems of CSP industry are analyzed and a series of solutions are proposed. Finally, the future directions of CSP and several improving measures are prospected.
Load Shedding Model and Algorithm Based on Minimum Power Outage Lose
Authors: Wang Yasong , Cao Zenggong , Wang Chunyi , Peng Bo , Du Peng , Guo Yinglei , Wei Zhen , Dong Xiaoming
Published: March 2021

This paper combines the power outage loss caused by load shedding with the optimization problem of load shedding during power shortage, and proposes a load shedding model that seeks the minimum power outage loss under the system’s security and economic constraints. The model is a kind of optimal power flow. In order to reduce the complexity of solving the model, this paper adopts an improved linear programming algorithm to solve the model. With the help of Jacobian matrix, the objective function and constraints of the system are linearized and the linear optimal solution in the iterative space of control variables can be found. Through multiple iterations the scheme with the minimum power outage loss is obtained that satisfies various constraints while the total power generation cost of the system is minimized The correctness and superiority of the model and algorithm are verified in the IEEE14-bus system.
A new method of safety detection in high-rise building curtain walls based on natural vibration frequency
Authors: Chen Chen , Xie Mowen , Du Yan , Pang Wei
Published: March 2021

With the development of curtain wall technology, the unit curtain wall has been widely used as a decorative component of high-rise buildings, but it has brought great difficulties to the later safety inspection. Based on the theory of thin-slab vibration, the laser vibration measurement technology in this paper is used to analyze the relationship between the multi-order natural frequency and the safety status of the point-supported experimental curtain wall model. At the same time, a corresponding finite element model is established to further quantify the natural frequency and restraining force on the curtain wall. The result shows that there are different relationships between natural frequencies of different orders and the safety of the curtain wall. In actual engineering, it is more sensitive for the first-order natural frequency to changes in the safety status of the curtain wall. A new method of safety detection in high-rise building curtain walls can be achieved by the combination of remote laser vibration measurement technology.
Optimization of Energy Storage Capacity to Smooth Wind Power Fluctuation
Authors: Cao Zenggong , Wang Chunyi , Peng Bo , Wang Yasong , Du Peng , Guo Yinglei , Wei Zhen , Dong Xiaoming
Published: March 2021

The uncertainty and randomness of wind power generation bring hidden trouble to the safe operation of power distribution network. Combining energy storage system with wind power generation can effectively improve the output characteristics of wind power generation. In this paper, considering the investment cost of energy storage and the effect of suppressing the fluctuation of wind power output, the optimization of energy storage capacity under the scenario of wind power grid connection is studied. Firstly, the multi-objective capacity optimization model of the energy storage system is established to minimize the cost of the energy storage system and the variance of wind power system output equipped with energy storage. Then, the multi-objective optimization problem is transformed into a single objective optimization problem by introducing the weight coefficient of the objective function and the particle swarm optimization algorithm (PSO) is used to solve the problem. Finally, through the test of IEEE-33 bus distribution network system, the relationship curve between energy storage capacity and wind power fluctuation suppression effect is obtained. The results of numerical examples show the effectiveness of the proposed method.
Numerical simulation of thermal environment in 320,000 tons VLCC engine room
Authors: Niu Anqi , Guo Mingxuan , Wang Jianli , Chen Meiqi , Jin Guoliang , Wang Shenghai
Published: March 2021

The engine room is the power center of the ship, including the main diesel engine and many other equipment, to maintain the stable operation of equipment in the engine room, to provide a comfortable working environment for the crew. The temperature and humidity in the engine room must reach a certain standard. There are ventilation systems in the engine rooms of ships, but we don’t have a good way to direct the lay out of the ventilation system. This paper takes 320,000 tons of VLCC as an example, uses FLUENT software to numerically simulate the temperature field and velocity field in the engine room, obtains the temperature distribution of the entire engine room, analyzes the simulation results, and proposes a ventilation layout optimization plan. Finally, the full text is summarized and the plan for further research is discussed.
Study on Determination of SF6 Decomposition Based on Gas Chromatography
Authors: Yan Honghua , Zhang Chuanping
Published: March 2021

The current research about SF6 switchgear failures mainly focuses on various troubleshooting methods, while ignoring the impact of SF6 gas decomposition products on equipment and the types of failures they reflect, and the application of SF6 gas decomposition products to diagnose equipment failures still needs to be further explored and improved. Therefore, this paper focuses on the study of the decomposition process of SF6 under partial discharge failure, and conducts theoretical analysis of the decomposition product composition of SF6 under partial discharge failure, and detects SF6 gas decomposition products by gas chromatography. Finally, it can be concluded that when the concentration of S2F10 and S2OF10 is about 5μL/L, the switchgear is likely to have a partial discharge failure. At this time, the maintenance personnel should deal with it in time to ensure that the switchgear can be put into use normally.
Research and Application of 66kV Internal Wedge Type Fast Tension Clamp
Authors: Jun Ma , Yonggang Shi , Gang Dong , Fuxing Gong , Zhu Wang , Lei Wang , Yu Ding
Published: March 2021

This research belongs to the field of live working of power transmission line, that is, 66kV internal wedge tension fast clamp fixture. The utility model comprises a clamp cone barrel which can pass through the conductor in the middle, a ring sleeve is fixed on the back of the clamp cone barrel, U-shaped bolts are inserted and screwed on the rear end faces of both ends of the ring sleeve, a line clamp connecting the insulator string is connected on the rear end of the U-shaped bolt, two ends of the line clamp are provided with connecting ring holes, and a connecting pin shaft is inserted in the ring hole. The structure is simple and reasonable, and the use is safe and reliable. It can solve the problem that there is no special clamp for 66kV fast tension clamp.
Topology Automatic Identification Method for Low-Voltage Stations Based on Line Impedance Analysis
Authors: Jiang Yan , Song Xueying , Lin Hua , Zhao Yupeng , Qiu Kaiyi , Yang Chao , Dong Shidanjie
Published: March 2021

Aiming at the problems of high cost, low real-time performance of manual identification of low-voltage station topological structure, automatic identification methods such as instantaneous power failure method and voltage correlation analysis method, which affect residents’ electricity consumption, and the success rate is limited by application scenarios, this paper proposes a method based on multiple linear regression Line impedance analysis method for automatic identification of the topology of low-voltage stations. Based on the relationship between voltage, current, and impedance, multiple linear regression analysis is used to derive the upstream topology step by step from the bottom up to the top of the topology and then determine the station membership by voltage correlation. The cloud platform based on Docker technology and Hadoop technology is used for data distributed storage calculation, and an identification model in the context of big data is established to effectively improve the efficiency of the algorithm. Finally, the correctness of the algorithm verification is judged based on the results of manual field verification.
Spacer for Double Bundle in Phase Conductor of Transmission Line Based on Cross Universal Joint Structure
Authors: Jun Ma , Yonggang Shi , Gang Dong , Fuxing Gong , Zhu Wang , Lei Wang , Yu Ding
Published: March 2021

This research belongs to the field of transmission line, that is, the double bundle inphase conductor spacer of transmission line based on cross universal joint structure. The utility model comprises a spacing rod, two ends of the spacing rod are provided with wire clamps, and the spacing rod and the wire clamp are connected by a cross universal joint, that is, one end of the spacing rod is provided with a fork, the fork is movably connected with two opposite axes of the cross shaft, the back end of the wire clamp is provided with a wire clamp fork, and the fork of the wire clamp is movably connected with another two opposite axes of the cross shaft. The utility model is to replace the ball joint structure of the existing double bundle conductor in the same phase spacer with the cross shaft universal joint structure, so as to increase the allowable range of movement of the spacer, avoid the fracture due to the force beyond the range, and meet the requirements for the installation and use of the double bundle conductor in the same phase of the transmission line. The structure is simple and reasonable, and the use is safe and reliable, which solves the problem that the spacer of the in-phase conductor of the original double bundle conductor of the transmission line is easy to break.
Design of electromagnetic compatibility test platform for transformer fire-fighting nitrogen injection extinguishing system
Authors: Wei Defu , Li Shengchuan , Wu Xinpeng , Song Yundong , Tan Rui
Published: March 2021

The transformer fire-fighting nitrogen injection extinguishing system plays an important role in preventing transformer fires in the field of power transformation. However, the fire-fighting system operating on site is often misoperation or non-operation caused by electromagnetic interference and other factors, which affects the reliability of transformer fire extinguishing. This paper builds an electromagnetic compatibility platform for the fire control cabinet of the transformer oil discharge and nitrogen injection system to develop the simulation system of the oil discharge and nitrogen injection fire extinguishing device, and study the factors affecting the reliability of the oil discharge and nitrogen injection fire extinguishing device. Electromagnetic compatibility test refers to a test that uses electromagnetic interference detection equipment and electromagnetic interference generation equipment to assess the electromagnetic compatibility of systems and equipment under laboratory or external environmental conditions. The electromagnetic compatibility test is mainly divided into electrostatic test, electric fast pulse EFT, surge impact and so on.
Discussion on Supervision and Inspection Method of High Temperature Bolt of Steam Turbine
Authors: Tian Chengchuan , Jiang Chong , Gao Zhiwei , Zhao Hai
Published: March 2021

Based on the failure analysis of high-temperature bolts in a thermal power plant, this paper proposed that the fracture mechanism of high-temperature bolts is mainly creep fracture. According to the bolt replacement and rejection criteria, the effectiveness of the current bolt supervision and inspection method was analyzed. It was proposed that the power station should strengthen the creep deformation measurement at the thread of the high-temperature bolt part, not just the screw part.
Failure Analysis for Disconnector Current Transfer Contact Falling off GIS Gas Chamber
Authors: Rong Huang , Yi Xie , Kejian Ouyang , Xianhui Cao , Chao Feng , Jun Wang
Published: March 2021

The withstand voltage test of GIS gas chamber disconnector in a new project of transformer substation was not passed. When the cover of the GIS gas chamber was opened, it was found that phase B of “E” rings current transfer contact and the corresponding accessories fell on the basin insulator at the bottom, and the current transfer contact falling off was the main reason for failing the withstand voltage test. Failed phase B & phase A of “E” rings and new sample were analyzed by size and weight test, hardness test, metallographic structure analysis, clamping force calculation and scanning electron microscopy (SEM) analysis. The analysis results show that the thickness value of “E” rings was less than standard value and the weight was not qualified, especially opening width and hardness of failed “E” rings were unqualified and had abnormal microstructure. Unqualified “E” rings and clamp failure caused current transfer contact to fall off.
Research on Strategy of distributed energy storage aggregators participating in peak load regulation auxiliary service
Authors: Dunnan Liu , Yuan Gao , Tingting Zhang , Jiahao Liang
Published: March 2021

In view of the peak shaving problem caused by high proportion of renewable energy connected to the grid, this paper proposes a trading mode in which the distributed energy storage aggregator participates in the peak shaving auxiliary service market, analyzes the operation mode of DSAP participating in peak shaving auxiliary service, and puts forward the optimization model and scheduling strategy of DSAP participating in peak shaving. The feasibility and effectiveness of DSAP participating in peak shaving auxiliary service are verified by numerical simulation.
Highly mesoporous and chemically bonded Fe3O4/N-doped carbon nanocomposite with an outstanding cycling life as lithium-ion-battery anode
Authors: Li Zhenwei , Li Jiayang , Han Meisheng
Published: March 2021

Owing to high theoretical capacity (926 mAh g−1), Fe3O4 has achieved much focus as a prospective anode material for lithium-ion batteries (LIBs). A one-step vapor-pressured induced approach considering the synthesis of chemically bonded Fe3O4/N-doped carbon nanocomposites (Fe3O4/NC) via Fe-O-C and Fe-N-C, together with the encapsulation of Fe3O4 nanoparticles (∼80 nm) into highly mesoporous N-doped carbon matrix via pyrolyzing the mixture of iron oxalate and dimethylformamide in a sealed vessel, does not exist at present. As LIB anode, the Fe3O4/NC presents a high capacity of 1250.2 mAh g−1 at 0.1 A g−1, an outstanding cyclability with a capacity of 600.1 mAh g−1 after 4000 cycles at 5 A g−1, and a high rate capability (244.8 mAh g−1 at 20 A g−1). Such excellent performances can be ascribed to its unique structure that Fe3O4 nanoparticles tightly encapsulated into highly mesoporous N-doped carbon matrix can increase active sites, electrical conductivity, and cyclability.
Field Experimental Research on Application of Strain Special Optical Cable and Parallel Optical Cable
Authors: Shi Ning , Bai Luyao , Ma Yunbin , Li Liangliang , Cao Jinggang
Published: March 2021

With the rapid development of China’s oil and gas pipeline mileage, pipeline construction will be unable to avoid crossing high-risk areas such as disaster risk areas, densely populated areas, environmentally sensitive areas. The traditional extensive pipeline patrol method has been unable to meet the requirements of fine management, which puts forward a new test for the upgrade of safety monitoring technology. In this paper, the distributed optical fiber sensing technology which has been studied intensively in recent years is introduced. Through in-depth analysis of pipeline requirements and characteristics of accompanying optical cable, a single-end BOTDA solution suitable for long-distance oil and gas pipelines is proposed. A 400-meter pipeline trench was excavated along the route of a domestic product oil pipeline. Strain special cables and GYTA53 cables were laid concurrently. Twelve strain monitoring sections were set up using vibrating wire strain sensors. The strain of two kinds of optical cables was monitored under various working conditions, such as partial backfilling, full backfilling, manual compaction and heavy mechanical compaction, as well as the monitoring values of two kinds of optical cable for soil temperature. The test results show that: 1) the strain-sensitive fiber optic cable is sensitive to strain feedback, and can produce rapid feedback to 2m3 pile soil, while the stress feedback of pipeline-accompanying fiber optic cable to soil is very small. 2) The temperature around the pipeline can be accurately reflected by the fiber optic cable, and it can be used for temperature compensation in strain monitoring.
Research and development of ultra-high temperature delayed crosslinking acid system
Authors: Xin Qiao , Pandeng Luo , Zhanqing Qu , Tiankui Guo
Published: March 2021

The average burial depth of carbonate reservoirs in Shunbei area exceeds 7300 meters, and the bottom hole temperature is as high as 160°C. The commonly used cross-linked acid system cannot meet the needs of acid fracturing. Therefore, this article uses AM, AMPS, acrylamide (AM) modified monomers, acrylic acid (AA) modified monomers to synthesize thickener SBCH-1, the organic zirconium crosslinking agent SBJL1 was synthesized with zirconium oxychloride, isopropanol, citric acid and diethanolamine. And other auxiliary agents are selected, and the final formula is determined as: 220% HCl+0.8% SBCH-1 thickener +0.8% SBJL-lcrosslinking agent +0.8% SBYC-1 crosslinking retarder +2% SBHS-1A high temperature corrosion inhibitor +2% SBHS-1B high temperature corrosion inhibitor +1% SBTW-4 iron ion stabilizer +1% SBZP-2 drainage aid +1% SBPR-1 demulsifier. The viscosity of the system stabilized above 200mPa⋅s after continuous shearing at 160°C, 170s-1 for 30min.
Economic analysis of distribution network planning considering decentralized energy storage system
Authors: Lei He , Sang Zixia , Huang Jiaqi , He Jifeng , Yan Jiong , Wang Qixin , Yang Dongjun , Du Zhi , Wu Lei
Published: March 2021

The rapid development of renewable energy makes the power grid gradually change from traditional power system to high proportion renewable energy power system. The rapid development of electric vehicles, energy storage and controllable load increases the uncertainty of load. The flexible adjustable load is less, which can not meet the consumption demand of large wind and solar power generation, and can not support the power valley filling demand when the wind power output is insufficient. Energy storage system is very important for the safe and stable operation of renewable energy internet. How to consider the reliability and economy, this paper proposes a distribution network planning scheme considering energy storage system.
Comprehensive evaluation of community fitness environment in multiple cities based on AHP-DEA integrated model
Authors: Wang Shichao
Published: March 2021

Based on the correlation between AHP and DEA, this study uses five aspects, four levels and 26 indicators to construct the evaluation index system and hierarchical structure model of fitness environment in urban communities along the ancient tea-horse road, and calculate the weights of criterion layer and index layer. the first-hand survey data is used to comprehensively evaluate the fitness environment of 9 urban communities, and the comparison and analysis of the individual cities evaluated are used to provide a paradigm reference for similar research.
A Polarimetric Interferometer Based on Composite Optical Waveguide for Refractive Index Detection
Authors: Du Bin , Mu Xihui , Liu Shuai , Liu Zhiwei , Liu Bing , Tong Zhaoyang , Xu Jianjie , Qi Zhimei
Published: March 2021

A sensitive interference refractive index sensor based on composite optical waveguide (COWG) was developed. Sol-gel technique was used to prepare TiO2 sol, and the TiO2 film was fixed on the surface of single-mode potassium ion-exchange (PIE) optical waveguide (OWG) by dip-coating and annealing treatment to fabricate an interference refractive index sensor device. The interference between the zeroth-order transverse electric (TE0) and magnetic (TM0) modes of the laser beam which transport in the COWG caused phase-difference change (Δϕ) of output light signals. Refractive index sensitivity of TiO2/PIE COWG chip was examined by injecting aqueous NaCl solutions and distilled water in turn to detect its Δϕ. Experimental results show that, for the TiO2/PIE COWG its refractive index sensitivity is SRI = (573.09 × 2π)/RIU in the refractive index ranges of 1.3386∼1.36. The sensor sees the advantages of high sensitivity, compact size, simple fabrication, as well as low cost.