bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of hybrid fibres on the mechanical properties of high performance concrete
Authors: SulphiaBeevi U , Joseph Anitha , Nazeer M
Published: July 2020

Fibre reinforcement is a technique used to provide toughness and ductility to brittle cementitious matrices. Reinforcement of concrete using a single type of fibre could improve the properties to a limited level. A hybrid composite refers to two or more types of fibres that are rationally combined to produce a composite that stems benefits from each of the individual fibres and exhibits a synergetic response. This study intends to illustrate and quantify the mechanical properties of Hybrid Fibre Reinforced Concrete. For this purpose, a reference High Performance Concrete (HPC) of grade M65 with water-binder ratio of 0.34 was used. Specimens of plain concrete mix, HPC with silica fume, Steel Fibre Reinforced High Performance Concrete (SFRHPC) containing only steel fibres, and Hybrid Fibre Reinforced High Performance Concrete (HFRHPC) containing steel fibres and carbon fibres were prepared. Optimum amount of silica fume was taken as 12.5%. The crimped steel fibre was added initially at 0.25%, 0.5%, 0.75%, 1% and 1.25% by weight of concrete and its optimum percentage was found out. Once the optimum dosage of crimped steel fibre was obtained, carbon fibre was used to replace the optimum steel fibre dosage at 25%, 50%, 75% and 100% by volume fraction. Thus an optimum hybrid fibre dosage was obtained. The mechanical properties of the HFRHPC like compressive strength, flexural strength, splitting tensile strength, modulus of elasticity and impact resistance were studied and compared with HPC mix. The results revealed that the addition of steel fibre improved all the mechanical properties of concrete.
Strength of concrete with wood ash and waste glass as partial replacement materials
Authors: Thomas Anu V , Ramaswamy K P , Nair Adarsh , Padmanabhan R , Isac Tom K , Anilkumar Vishnu
Published: July 2020

This paper discusses a study on the use of wood ash as partial replacement of cement and waste glass as partial replacement of fine aggregate in concrete. Wood ash was used to replace cement at 5% and 10% and waste glass was used to replace fine aggregate at 10% and 15%. When wood ash was added to concrete, the compressive strength of concrete was found to reduce marginally with respect to the reference mix and the optimal value of compressive strength was obtained at 5% replacement. Addition of waste glass to replace fine aggregate resulted in marginal reduction of compressive strength of concrete at 10% replacement. However, a drastic reduction in compressive strength was observed at 15% replacement level of waste glass. Replacing 5% of cement with wood ash and 10% of fine aggregate with waste glass yielded satisfactory results and thereby at these replacement levels, wood ash and waste glass can be used as replacement materials in concrete. Incorporating the waste materials in concrete will be an efficient and effective way to dispose these materials and will result in lower consumption of natural materials in the manufacturing process of concrete thereby resulting in an environment friendly and cheaper concrete.
Effects of slag and superplasticizers on alkali activated geopolymer paste
Authors: Raju Thushara , Ramaswamy K P , Saraswathy B
Published: July 2020

Geopolymers are a type of amorphous alumino-silicate product, and can be synthesised by the polycondensation reaction of geopolymeric precursor and alkali polysilicates. The binder is prepared by the alkaline activation of industrial by-product materials like fly ash, slag, metakaolin, rice husk ash, etc. as a source for aluminosilicate. The most commonly used alkaline activator is the combination of sodium hydroxide (NaOH) and sodium silicate (Na2SiO3). Chemical admixtures are indispensable in alkali activated systems owing to its poor fresh properties such as workability, too quick setting etc. In this study, the chemical admixture – alkali activated binder interactions were carried out by using latest generation superplasticizers, such as Polycarboxylic ether admixture (PCE) and Sulphonated naphthalene formaldehyde (SNF). Mini slump test, initial and final setting time tests were conducted in alkali activated slag blended fly ash based geopolymer paste and the test results were analyzed with respect to parameters such as alkali to binder ratio (a/b), proportion of slag in blended geopolymer paste, type and dosage of superplasticizers. The test results indicated that the workability and setting time of alkali activated geopolymer paste enhanced due to the increase in alkali content and the reduction in slag content. Based on the effect of chemical admixtures in geopolymer mix, SNF performed better than PCE admixture with regards to mini slump test for all the mixes; whereas in the case of setting time test, SNF showed better results only for the mix with 100% slag. In the case of slag blended fly ash based geopolymer paste, both PCE and SNF showed similar effects, and also it was observed that, the flow of the paste got enhanced when the dosage of superplasticizers is increased from 0 to 3% by weight of binders.
Effect of superplastizicer type on the fresh and strength properties of alkali activated slag composites
Authors: Muhammed Nabil K , Namitha S , Sundhar Reshma , Mohammed Rafeeque N V , Raju Thushara , Ramaswamy K P
Published: July 2020

Nowadays, the demand for green concrete has increased due to the greenhouse gas emissions and uncontrolled pollution from the cement industry. At the same time, the green concrete should exhibit better mechanical properties and durability characteristics when replacing conventional concrete without compromising on the fresh properties. A better solution for the production of green concrete is to use air cured Alkali Activated Slag (AAS) composites, an innovative and sustainable binding material with very low carbon footprint. However, AAS exhibits demerits such as quick setting and poor workability and this demands the use of superplasticizers in such binder systems which are less explored thus far. Hence, this paper presents a study on the influence of superplasticizer type on the fresh and strength properties of AAS mortar. Paste/mortars were prepared with alkali activators composed of sodium silicate and sodium hydroxide and tested to study the setting times, workability, and evolution of compressive strength. It is found that the fresh properties are improved by increasing the alkali to binder ratio and the dosage of superplasticizer. Both sulphonated naphthalene formaldehyde (SNF) and polycarboxylate ether (PCE) based admixtures were found to be effective in alleviating the negatives of air cured alkali activated paste/mortar systems.
Application of artificial intelligence techniques in prediction of cyclic resistance ratio (CRR) of clean sands
Authors: Akhila V , Adarsh S
Published: July 2020

Liquefaction study by in-situ tests like SPT and CPT are very complicated and time consuming. Cyclic Resistance Ratio (CRR) of a soil is controlled by various properties of the soil. Artificial intelligence techniques can identify relationship between various parameters which influence the liquefaction phenomenon from sufficiently large data set to generate models connecting those parameters. Models for prediction of cyclic resistance ratio (CRR) of clean sand is generated using MGGP, GPR and M5’ model tree in the present study using data from cyclic triaxial test and cyclic direct shear test. Using 346 data points, divided in 50% train to 50%test ratio, sufficiently accurate models were generated through the algorithms considered. These algorithms were compared by means of the Root Mean Square Error (RMSE), Coefficient of correlation (R2) and Maximum absolute Error in prediction (MAE). An equation connecting the CRR with other input parameters was developed using the MGGP algorithm, which also showed the maximum R2 value of 0.96 for the test data. The AI algorithms were observed to satisfactorily model the relation between the input parameters and the CRR without any prior knowledge of the same.
Study of fin shape on the behaviour of finned piles under combined loading conditions
Authors: Ambi Rekha , Jayasree P K , Unnikrishnan N
Published: July 2020

Several types of structures, such as bridge abutments, retaining walls, transmission line towers and other structures exposed to wind and earthquake loads, supported by pile foundation are being subjected to large lateral loads. Finned pile is an emerging form of pile foundation that is capable of resisting large lateral displacements. Here, it is attempted to assess the effect of the shape of fins on the lateral carrying capacity of a pile with fins subjected to combined loading conditions. Small-scale laboratory model tests were performed on normal piles (without fins) and also with finned piles. These piles were embedded in sand. The studies were carried out by varying the geometric factors such as length, width and shape of the fins. Results show that there is a substantial increase in lateral resistance capacity of the piles after fitting the fins close to the pile head. The increase in lateral resistance capacity gained by placing fins on a pile varies with dimension of the fins. On the basis of the laboratory model test results, optimum dimension of the fin for maximum improvement are recommended for combined loading conditions. The trend showed in the results were comparable with those reported in the literature as on studies with lateral load alone.
Performance evaluation of Indian air routes
Authors: Thomas N , Handuja V , Iyer K C
Published: July 2020

India is witnessing a massive growth in the aviation industry. In 2016, the Government of India had launched Regional Connectivity Scheme (RCS), also known as UDAN (Ude Desh ka Aam Naagrik) which translates as ‘let the common citizen of the country fly’. It aims to make flying affordable for the masses, promote tourism, increase employment opportunities and promote balanced regional economic growth. The scheme incentivises the airlines to fly in non-financially viable regional routes. This study employs data envelopment analysis (DEA) approach to evaluate the performance of 33 domestic air routes of India after UDAN has launched. The parameters for evaluation of the efficiency have been established using the literature survey and pilot studies. Four input variables (air distance between airports, VGF (Viability Gap Funding) sought, maximum airfare, the capacity of routes) and one output variable (load factor) are selected for the analysis. The results of DEA model demonstrate that eight routes are relatively efficient operationally. This performance analysis can be used to assess the management actions and strategies in developing more effective decision making for satisfying the objectives of the owners or operators of airports.
Sand Free Rate Enhancement with Aqueous-based Selfhealing System
Authors: Li Jianda , Zhang Guicai , Ge Jijiang , Qiao Wenli , Jiang Ping , Pei Haihua
Published: July 2020

Unconsolidated sandstone reservoirs are susceptible to sanding problems. Traditional sand consolidation methods are often not environmental-friendly or ineffectively. This paper proposed a new sand consolidation treatment with aqueous-based self-healing system (ABSH) to maximize the sand free rate. The ABSH performs well with a relative lower dosage in laboratory tests. Sand consolidation performance and chemical resistance property were evaluated using the maximized sand free rate as indicators. After aging for 12 hours, the maximized sand free rate of consolidated sand pack could be prominently increased to 6600mL/h. Re-agglomeration ability between sand particles was illuminated by adhesion force tests. The adhesion force could be almost 90% of the original one after the contacting and separating process proceeded for three times.
Application of Pipeline System Stress Analysis in Inspection
Authors: Pu Zhe , Ren Bin , Tang Xiaoying , Wang Jifeng
Published: July 2020

Industrial pipeline is generally laid overhead along the pipe gallery. When the pipeline changes from cold state to heat state, the pipeline will have thermal expansion, which will generate thermal displacement and thermal stress. As a kind of heat medium, Steam has been widely used in industrial production. The pipeline has been in service at high temperature for a long time, which is prone to metal material degradation such as graphitization and spheroidization. The accidents of steam pipeline occurred frequently in recent years, so we must pay more attention to the safety of steam pipeline. The traditional inspection method adopts a random sampling model which has the risk of over inspection and missing inspection. This paper introduced the stress analysis of a steam pipeline based on ASME B31.3. Through the software, the model of the pipeline was established. According to the calculation results, a targeted inspection scheme was established and the inspection was more economical and effective
Microwave-assisted Acid-catalyzed Hydrolysis of Hemicelluloses in Rice Husk into Xylose
Authors: Zhang Mingyu , Wang Ya , Hui K. S. , Liu Lizhu , Zhang Chunqi
Published: July 2020

The development of an environmentally benign process for the hydrolysis of hemicelluloses into xylose could be one of the key technologies for making full use of biomass in the future. This paper studies dilute acid hydrolysis of hemicelluloses in rice husk (RH) into xylose using microwave radiation. Fourier transform infrared-attenuated total reflection spectroscopy was employed to quantitatively analyze xylose. The influences of hydrolysis parameters such as temperature, time, acid concentration, and ratio of RH to sulfuric acid on the yield of xylose in acid hydrolysis of RH were also investigated. The optimum hydrolysis conditions of hemicelluloses in RH to xylose are as follows: 4 wt% of H2SO4 concentration, 150 °C hydrolysis temperature, 25 min reaction time, and 1:7 ratio of RH (g) to H2SO4 (mL). Under optimum hydrolysis conditions, a yield of 32.96% xylose is obtained.
Investigation on Tribology Behaviors of Oil-soluble Nano-Cu Lubricating Additive for Aluminum Alloy ZL101
Authors: Wang Yonggang , Li Na , Liu Hui , Wang Junge , Huang Jialei
Published: July 2020

Oil-soluble Nano-Cu lubricating additive was prepared and its tribology behaviors as lubricant additive in SJ 15W/40 heavy duty gear oil used for aluminum alloy material ZL101 were investigated on an end-face friction and wear tester apparatus. SEM and EDS techniques were used to characterize the morphology, compositions and chemical states of the worn surface. The results indicate that the oil-soluble Nano-Cu additive have excellent friction-reducing properties and 0.6wt.% addition exhibited the best friction behavior. An appropriate applied load and rotating speed can improve the tribology properties obviously. The combination of SEM-EDS analysis reveals that by addition of Cu nanoparticles, a tribo-film containing Cu nanoparticles was formed and helped improving the wear and friction properties. The results demonstrate that Cu nanoparticles are potential friction modifier when used in ZL101.
Exergy destruction calculation and analysis for a Coal drying system
Authors: Jing Xuye , Shi Zhansheng , Ma Zhian , Peng Li , Dong Fang , Xu Bo
Published: July 2020

A coal drying system was modelled and the calculation methodology was developed to calculate the system. Then the system performance was obtained and the exergy destruction and loss in the system is 70.5 kW. The reasons of exergy destruction were tried to be explained from the perspective of energy grade. In DRY-REAC, the wet coal was dried to dry coal, the process of which is irreversible, and the main exergy destructions are used to pay the thermodynamic penalty of the increased energy grade of the wet coal.
Research advances on driving mechanism of nitrogen and phosphorus loss in sloping fields
Authors: Gong Xinfeng , Qin Tianling , Wang Huiliang , Nie Hanjiang
Published: July 2020

Slope runoff and its associated soil nutrient loss are affected by precipitation, topography, underlying surface conditions and soil physical and chemical properties. The loss of nitrogen and phosphorus in slopes is an important cause of soil quality degradation and eutrophication of water bodies. Therefore, based on the study of rainfall runoff, the loss of soil nutrients and the change of runoff quality in the process of runoff can be further analyzed, which can provide reference for controlling nutrient loss and revealing the mechanism of nutrient loss. In this paper, the current situation of the study on the loss of nitrogen and phosphorus in sloping fields at home and abroad is analyzed from five aspects of precipitation, topography, soil characteristics, vegetation and human activities. The possible research directions in the future are put forward from three aspects of precipitation characteristics, topography and vegetation conditions, so as to provide ideas for more systematic study on the loss mechanism of nitrogen and phosphorus in sloping fields.
Identification method of water-flooded layer based on analytic hierarchy process——Taking the Keshang Formation reservoir in the J188 well area as an example
Authors: Liu Wengfeng , Zhang Xuyang , Wang Kang , Yang Yufeng , Liu Xin , Zeng Shuling , Chen Jing
Published: July 2020

Most oil fields in China have entered the high water cut stage, the identification of water flooded layers is a very important task. At present, the identification of water-flooded layers usually adopts the combination of qualitative method and quantitative method to carry out the work. However, the qualitative method is difficult to be characterized by quantitative numerical values, so the work efficiency is very low; the quantitative method needs to be taken in the actual operation. The oil-water relative permeability of the reservoir, the viscosity of the oil and water, and the original oil saturation, the calculation accuracy of these parameters are inevitably large errors. This paper explores a semi-quantitative method to overcome the insufficiency of qualitative methods, the simplification of quantitative parameters, and the error of water-flooded layer identification. The analytic hierarchy process was used to identify the water-flooded layer in the Keshang Formation reservoir in the 188 well area. The water production rate, oil saturation, production index and relative permeability index were integrated into a comprehensive water-flooded layer identification index. The results show that the total water-flooded layer identification coincidence rate reaches 70%. The method of water flooded layer identification based on analytic hierarchy process is feasible.
Monitoring and analysis of external deformation of face rock-fill dam during initial storage period
Authors: Li Xiuwen , Wu Hao , Tian Dongcheng , Zhang Shunfu
Published: July 2020

During the initial storage period of the face rock-fill dam, its physical and mechanical properties will not be in a fully controlled state when it is subjected to the test of water loads, which may cause certain safety risks. The stability of the dam body and slope can be analyzed by studying the external deformation changes of the face rock-fill dam after water storage. This article analyzes the external deformation monitoring data of the Hekou Village Reservoir’s face rock-fill dam during the initial storage period, and it reveals the general rule of the external deformation of the face rock-fill dam after water storage. The results also show that the dam is safe after storing water and have certain reference significance for other similar projects.
Short-term Effect of Intelsat-29e Explosion on GEO Environment
Authors: Yiwen Hu , Zhanyue Zhang , Hongqiang Sun , Kaixi Liu
Published: July 2020

Geosynchronous Orbit (GEO) space environment model of the orbital targets with a size above 10 cm was established according to the amended data and space density. The situation of satellite explosion on GEO is simulated, including the number of fragments generated by the explosion, the size distribution as well as the corresponding mass distribution of the fragments. Under the conditions of selecting fragments of different size for analyzing, the area to mass ratio, discrete velocity, and apogee-perigee distribution can be obtained. By simulating the collisions of targets in different size and mass, and the evolution of the space environment when different size thresholds are selected, the necessity of establishing the GEO space environment and evolution model with the threshold size of 10 cm is demonstrated. The feedback collision caused by the fragments generated by the GEO satellite explosion is simulated under the conditions of different collision probability thresholds. The results show that the explosion fragments would cause a high collision risk environment for other GEO orbital targets, and the risky circumstance would last for hours. The impact of explosive debris on the security of the future space environment is analyzed
Dewatering Design of a Foundation Pit
Authors: Xiao Ma , Peng Mu
Published: July 2020

Foundation pit dewatering project is one of the important guarantee measures for the smooth construction of building foundation under the groundwater level. Through hydrogeological investigation and precipitation test, to find out the hydrogeological conditions of the site and obtain accurate hydrogeological parameters is the basis of determining the best precipitation scheme which is safe, reliable, economic and reasonable. Taking the dewatering design of a foundation pit as an example, the analysis and summary are made.
Analysis of ultimate bearing capacity of pressure spherical shell with openings
Authors: Wei Yan , Jianting Guo , Yong Shen
Published: July 2020

As the main pressure bearing structure of the deep submerger, it is inevitable to open manholes and observation holes on the pressure spherical shell, and the openings will affect the ultimate bearing capacity of the pressure spherical shell. In this paper, 7000m pressure spherical shell is taken as the research object, the finite element model of the spherical shell is established based on ANSYS, and the influence of the opening size on the ultimate bearing capacity of the spherical shell is calculated. At the same time, the trunk bulkhead strengthening method is adopted, and the thickness and height are taken as variables to calculate the change of the ultimate bearing capacity under different working conditions. The results show that the wall strengthening can significantly reduce the influence of opening on the pressure spherical shell, and the appropriate increase of thickness or decrease of height can increase the ultimate bearing capacity of the structure.
Study on spatiotemporal difference and influencing factors of grassland yield in sunan county of Gansu province
Authors: Yan Jixuan , guangping Qi , Sun Dongyuan , Zheng Zhiqin , qiang qiao Hong , guang Li
Published: July 2020

Grassland ecosystem is the most important terrestrial ecosystem. Only by accurately estimating grassland yield and productivity can we effectively protect the ecosystem. This thesis is based on 323 monitoring data and MODIS-NDVI and MODIS-EVI vegetation index corresponding to the same period from 2012 to 2016, Based on the establishment of grassland yield estimation model, the grassland yield of Sunan County was estimated. The results show that: (1) After validating the model equations corresponding to the five production areas through the reserved precision verifying points, the model accuracy is higher than 90%, and it is feasible to estimate production by remote sensing.(2) From 2012 to 2016, the average yield of grass in Sunan County was 89.92 million tons, and the average yield per unit area was 524.12 kg/h m2.(3) Grass yield in Sunan County decreased from southeast to northwest during 2012-2016, and the overall grass yield showed a slow downward trend.(4) The annual grass yield in the study area is directly proportional to the annual precipitation and average annual temperature, and the annual precipitation has a greater impact on the annual grass yield.
Numerical study on the evolution of cloud microphysical characteristics during rainfall processes of typhoon Bolaven in 2012
Authors: Zhang Zhiwei , Li Sicong , Li Yunying
Published: July 2020

The cloud microphysical characteristics in a rainfall process of typhoon Bolaven is studied by the WRF model. The results indicate that the maximum values of different cloud microphysical parameters occur at different times, strong ascending motions have an important impact on the evolution of cloud microphysics. More than four hours before the peak of rainfall, ascending motions are strongest and occur primarily above the 0°C layer, water vapor is lifted to the upper troposphere and frozen. With increasing rainfall, the core of the strong ascending motion decreases. When the core of the strong ascending motion decreases below the 0°C layer, the amounts of both rainwater and cloud water increase rapidly and reach their maximums at and after the peak, respectively. The vertically integrated cloud water content maintains its maximum for approximately three hours in torrential rain, and cloud water is continuously collected by rainwater.
Prediction of subsidence deformation of subway project by improved markov chain and optimized wavelet neural network model
Authors: Lijuan Luo
Published: July 2020

In view of the fact that the factors affecting the subsidence deformation of subway engineering are complex and the subsidence monitoring data are random, this paper constructs an optimized wavelet neural network model with markov chain improvement to improve the accuracy of the predicted data. Firstly, the wavelet neural network is optimized by adding momentum and adjusting learning rate adaptively. Finally, based on markov chain theory, the residual between the predicted value and the actual monitoring value of the optimized wavelet neural network is improved. Taking the settlement data of a settlement monitoring point of xi'an metro line 14 as the research object, the prediction accuracy of the model was compared and analyzed by C++ program. The results of the program show that the additional momentum and the adaptive learning rate are effective for the optimization of the wavelet neural network model, and the prediction accuracy of the optimized wavelet neural network model improved by the markov chain is higher than that of the single model, which is suitable for the prediction of the subway engineering settlement.
Mutual grafting affects the physiology of two Solanum photeinocarpum ecotypes under selenium stress
Authors: Liao Renyan , Fan Zhengkang , Peng Huaiqing , Huang Kewen
Published: July 2020

The aim of this pot experiment was to determine the grafting affecting the physiology of twoSolanum photeinocarpumecotypes under selenium (Se) stress. TwoS. photeinocarpumecotypes (farmland and mining) were subjected to mutual grafting, and then their physiological characteristics were determined after growth in soil containing Se at 10 mg kg−1. Compared with ungraftedS. photeinocarpum, the combination of the scion (farmland ecotype) and the rootstock (mining ecotype) showed increased photosynthetic pigment contents, while the opposite grafting combination showed decreased photosynthetic pigment contents. Mutual grafting also increased the antioxidant enzyme activity graftedS. photeinocarpum, and these parameters showed the highest values in the combination of the scion (farmland ecotype) and the rootstock (mining ecotype).
A Study on Development Abilityof Fishery Economy in China Based on Factor Analysis
Authors: Yu Lei , Xu Zhicang
Published: July 2020

The thesis adopts the factor analysis method, taking 11 indicators reflecting the fishery economic development capacity as the research object, and measures the output capacity, input capacity and comprehensive development capacity of China’s fishery economy from 2009 to 2018. The results show that the input capacity of the fishery economy is significantly higher than the output capacity of the fishery economy; the pulling effect of the input capacity of the fishery economy on the output capacity of the fishery economy varies from strong to weak; the speed gradually slowed down.
Process of Soil Erosion Study Method
Authors: Zheng Yanshuang , Lin Jing , Li Binbin , Liu Jie , Liu Mingxin
Published: July 2020

The study methods of soil erosion and main soil erosion prediction model are introduced in this paper. The soil erosion study methods include the erosion features survey procedure, test plot long-term monitoring, rainfall simulation experiment in laboratory, agrology method, river gauging, remote sensing method, nuclide traces method, soil erosion prediction model method et al. The soil erosion prediction model includes the USLE and RUSLE, CSLE, WEPP, YWYM et al. We introduced the relative merits about these soil erosion study methods and soil erosion prediction model in this paper.
Strategic Sustainability Plan In Denpasar 2040
Authors: Liu Yuchen , Tao Hongyi
Published: July 2020

By 2040, Denpasar will become a vital international city. There are traditions flourishing and unique cultural history alongside sustainability innovations, modern technology, and empowered communities. Its core is that Denpasar embraces traditional philosophy, harmony with God, people and the environment. This report discusses various strategies for making Denpasar a sustainable city in 2040. The region’s natural resources are managed fairly and sustainably to enhance social cohesion and improve resistance to environmental risks. The city will reduce waste through a variety of economic, extensive reuse and waste recycling projects and support a wide range of industries and opportunities for the Denpasar people. Tourism will continue to promote employment and the economy without compromising related ecosystems and biodiversity. Denpasar will not only thrive, but will also be sustainable.
Research Progress of Remedying the Heavy Metal Contaminated Soils with Rape
Authors: Ma Lin , Zhao Yutong
Published: July 2020

The problem of heavy metal pollution in soil is becoming more and more serious, which seriously threatens the ecosystem and human safety. In recent years, there have been more and more studies on the use of plants to remediate heavy metal contaminated soil. The toxicity of rapeseed and the detoxification mechanism of rapeseed to heavy metals, the enhancement method of rapeseed in the remediation of heavy metal pollution in soil, and the research prospect of remediation of heavy metal contaminated soil by rapeseed.
Analysis on Composite Erosion Process Based on Multi Dynamic Erosion Environment Simulation
Authors: Yang Chunxia , Zhen Bin , Zhang Pan , Xiao Peiqing
Published: July 2020

Using the compound erosion experimental device developed by ourselves, the compound erosion process simulation experiment of 35° steep slope were carried out under different combination modes of freeze-thaw, wind, rainfall. The runoff and sediment yield change process of Pisha sandstone slope under different dynamic combination environment were studied. The results show that the superposition of wind, freeze-thaw and rainfall conditions obviously promotes the occurrence of slope erosion, among which the effect of freeze-thaw increased the collapse phenomenon obviously in the erosion process.
Analysis on the Influences of Temperature on the Moisture Detection of Transformer Bushings
Authors: Gu Zhaoliang , Zhu Wenbing , Zhu Mengzhao , Xu Wei , Gao Zhixin , Yi Feng
Published: July 2020

Insulation damp is the main cause of transformer bushing failures. Dielectric loss detection, as the most important method to evaluate the insulation state of transformer bushing, has been widely used in the evaluation of transformer bushing dampness. But its accuracy of detection will be affected by temperature and other environmental factors. The real capacitor transformer bushings have been taken as the research object to simulate the real situations of transformer bushing dampness in this paper. The relationship between Dielectric loss values and temperature of transformer bushings with different moisture concentrations have been obtained. And the influences of temperature on the moisture detection of transformer bushings are also studied. These results can provide reference for the accurate dielectric loss detection of transformer bushings and the diagnosis of dampness degree.
The Effects of Different Planetary Boundary Layer Schemes on the Meteorological and Environmental Elements in winter stable weather of Shenyang
Authors: Wang Yangfeng , Lu Zhongyan , Zhang Guangmei , Ren Wanhui , Wan Xujiang , Ma Yanjun , Zhang Yunhai
Published: July 2020

Two planetary boundary layer schemes (YUS and MYJ) in the WRF-CMAQ model, are selected for sensitivity simulation, and the simulation capabilities of different planetary boundary layer schemes to meteorological elements and PM2.5 concentration distribution are analyzed from December 17th to December 20th in 2016. The results show that using the YSU and MYJ schemes can well simulate the spatial distribution and diurnal variation characteristics of temperature, wind speed and PM2.5 concentration on the ground under the background of stable weather in winter. It is sensitive to temperature, wind speed and PM2.5 concentration on the ground using different planetary boundary layer parameterization schemes. The simulated wind speed is relatively large, and the maximum deviation can reach about 2m/s. The deviation of wind speed using the MYJ scheme is relatively small than YSU, which is closer to the real value. There has a lower PM2.5 concentration value using YSU than MYJ at night, however the daytime (mainly from 11:00 to 18: 00) YSU scheme is relatively higher than MYJ. The deviation of PM2.5 concentration on the ground using the MYJ scheme is relatively smaller than YSU, and the characteristics of daily variation is closer to the real situation. Overall, the MYJ scheme is better than YSU in air pollution simulation.
1D seismic site response analysis for a soil deposit at Baoding city
Authors: Jia Qijun , Wang Duguo , Zhai Fenlou , Liu Xiaoyu
Published: July 2020

Based on 1D equivalent linear method, the effect of a soil deposit at Baoding city on wave propagation was analysized. Firstly, probabilistic seismic hazard analysis (PSHA) was performed, and the peak accelartion and response spectrum of outcrop with exposure rate over 63%, 10% and 2% in 50 years are obtained; secondly, the artificial earthquake ground motions used as input motion of soil deposit were synthesized; lastly, 1D equivalent linear analysis was performed to evaluate the effect of soil deposit on wave propagation. Results show that soil deposit has a great influence on wave propagation. The intensity of input motion also plays an important role on the properities of seismic ground motion.
Structural design and analysis of Yanqi Lake ecological development Demonstration Area in Beijing
Authors: Zhang Xiaomeng , Liu Wenting , Gao Bo , Ding Weilun , Yang Jie , Li Sen , zhou Yilun
Published: July 2020

Beijing lake yanxi ecological development demonstration project, a total of 60 square meters, consists of eight 50 tower and garage, tower, a total of seven family, layer number ranged from 8 to 15 layers, structure with shear wall structure, garage mainly adopts frame structure, through the choice of different structure and introduction, the structure system is analyzed.
Study on creep characteristics of unsaturated sericite schist residual soils
Authors: Liu Huan , Lian Xiao-lan , Nie Guang-ying , Zhang Qing-wen
Published: July 2020

Sericite schist is an extremely soft rock, which is characterized by obvious rheological properties and large creep deformation. The residual soil of Sericite schist is in unsaturated state for most of the time. When encountering water, it interacts with water, which has a great influence on its strength. In this paper, one dimension and three axis creep tests of Sericite schist residual soil are carried out by using unsaturated quadruple consolidation apparatus and unsaturated triaxial creep apparatus. The results show that the creep process of the residual soil can be divided into three stages: rapid growth stage, slow growth stage and stable stage. The creep deformation of triaxial test is larger than that of one dimension.
Effects of different hormones on germination and callus induction of hemp seeds
Authors: He Bingqing , Shen Penglin , Zheng Hongjuan , Chu Yi , Guan Jinqiu , Li Lan
Published: July 2020

The purpose was to induce and treat hemp seeds and callus, compare the methods to increase the germination rate of hemp seed, obtain suitable disinfectant for hemp seed, and different hormone ratios to promote callus growth. GA3, 6-BA, and IAA were used to induce hemp seed germination, and the effects of different hormones and different concentrations on hemp seed germination were studied. Tissue culture was used to induce hemp seeds to select suitable hemp seeds disinfectant and time; callus was induced by using hemp aseptic seedling leaves. GA3 with a concentration of 20-80mg/L and IAA with a concentration of 20-40mg/L can promote the germination of hemp seeds; the best disinfection method of hemp seeds is: 70% ethanol for 1min + 10% NaClO for 18min; the most the combinations beneficial to callus growth were: 2.0mg/L 6-BA+0.5mg/L NAA. GA3 and low-concentration IAA can promote the germination of hemp seeds; the combination of 70% ethanol and 10% sodium hypochlorite has the best disinfection effect on hemp seeds; 6-BA+NAA can obtain good quality hemp seeds hemp callus.
Effect of Dry-Wet Cycle on Stability of Granite Residual Soil Slope
Authors: Wang De-Yong , Zeng Qing-Jun , Wang Jing , Zhou Mi
Published: July 2020

The dry-wet cycle has a significant effect on the shear strength of the granite residual soil, which will affect the stability of the slope. A numerical model of the road cutting slope considering the strength change of the granite residual soil under conditions of dry-wet cycle was established. The numerical model was compared with the previous research results to obtain a good agreement, indicating the validity of the model established. Then several influence factors such as the number of cycles, initial cohesion, friction angle, initial slope angle, excavation slope angle and other factors are considered, and the parameter analysis of the stability development of the road cutting slope with the strength changes of the granite residual soil under dry and wet cycling conditions is considered. The research results show that the dry-wet cycle has a great impact on the stability of the road cutting slope of granite residual soil, which reduces the slope stability by about 10-30%. The conclusions of this paper provide a certain theoretical guidance for the design and application of the roadside slope engineering of granite residual soil.
Theoretical Analysis and Finite Element Verification on Natural Vibration of Special Water Tower Structure System
Authors: Ji Jing , Kang Wei , Xu Ming , Li Zhihui , Jiang Liangqin
Published: July 2020

In order to master the dynamic characteristics of this special engineering structure, based on the advanced structural dynamics, the water tower structure is simplified as a single degree of freedom vibration model according to the mass concentration method, and the analytical solution of the free vibration fundamental frequency of the water tower structure is derived. The three-dimensional finite element model of the water tower is established by using the finite element software ABAQUS, and the modal analysis of the water tower structure is carried out. The simulation fundamental frequency and vibration mode of the water tower structure are obtained. Through comparison, it can be seen that the analytical solution of the free vibration fundamental frequency of the water tower structure is in good agreement with the simulation result, which verifies the correctness and application scope of the analytical solution of the free vibration fundamental frequency of the water tower structure. It can be seen that the mass concentration method proposed in this paper can accurately calculate the fundamental frequency of water tower structure. Finally, the seismic design suggestions of water tower structure are given.
Determination principle of residual Gas and Analysis of influencing factors on the results of Laboratory Measurement
Authors: Yang Hongwei , Han Bing , Qian Zhiliang
Published: July 2020

In view of the current situation that the concept of residual gas content in coal seam in our country is relatively chaotic, the definition of residual gas content and the measurement principle of degassing and desorption methods in “The direct method of determining coalbed gas content in the mine” are analyzed. The standard unified method and the explicit concept are proposed. Through the laboratory desorption experiments in some mining areas, it is found that the residual content of gas and the degree of coal metamorphism are positively correlated as a whole. There is a negative correlation between the content of ash and internal moisture in coal and the residual content of gas. The order of the residual gas content of different sampling methods is as follows: core sampler> hydraulic slag sampler ≈ wind slag sampler, coal structure is complete, the change range of measured data is the smallest with core sampler, which can truly reflect the law of coal desorption and status.
China’s Incubator Industry Efficiency Evaluation——Based on DEA Analysis of Provincial Data
Authors: Jin Lanqing
Published: July 2020

This paper evaluates the efficiency of China’s incubator industry based on DEA (Data Envelopment Analysis) of provincial data in 2017. We use DEA method to test the efficiency of industrial input-output. Through the empirical test we find that the overall efficiency of China’s incubator development is high, while the efficiency of various regions is not balanced, and some provinces are inefficient. In the end, we put forward suggestions at government level, the intermediary organization level and incubator level. At the government level, the systems and mechanisms should be innovated, market-oriented reforms should be put forward, and the enthusiasm for investment and participation should be stimulated. The intermediary organizations should actively establish cooperation platform and invest with the incubator. The incubators should enhance their own value-added ability, give play to the advantages of the group to attract more investment.
The Impact of Cultural Festivals on the Development of Rural Tourism - A Case Study of Da Jia Matsu Pilgrimage
Authors: Lin Hsiao-Hsien , Hsu Chin-Hsien , Liu Chih-Yu , Cheng Bai-You , Wang Ching-Hsin , Liu Jen-min , Jhang Shangwun
Published: July 2020

This study aimed to the impact of cultural festivals on the development of rural tourism to explore. We took the Da Jia Matsu Pilgrimage as an example, and investigated the residents of the counties and cities along the pilgrimage route. SPSS for Windows 22.0 was used to conduct the t-test, and the descriptive statistical analysis to 2072 samples. The research result is residents in different regions regarded that the pilgrimage could unite the people, improve community environments, preserve traditional culture, maintain public facilities, and increase public infrastructure. Male residents argued that the pilgrimage could only unite the people, while female residents asserted that it could increase public infrastructure and service measures, preserve traditional monuments, and improve community environments; however, it also resulted in traffic accidents and the disturbance of living spaces. The research conclusion is residents of different places and genders have different understandings in terms of the economic, social, and environmental impacts on the Da Jia Matsu Culture Festival. The research suggestion is the schedule and investigation of the places along the pilgrimage can be extended to include other cultural festivals and different impacts on stakeholders.
The Influence and Measures of Developing Sightseeing and Leisure Agriculture on Rural Economic Development
Authors: Yang Jian
Published: July 2020

This paper starts with the analysis of the current situation of China’s modern sightseeing and leisure agriculture, and then makes an in-depth analysis on how to actively develop sightseeing agriculture in the contemporary era, including detailed discussion and planning on improving the quality of residents, scientifically planning sightseeing agriculture, strengthening the attention of the countryside to modern sightseeing agriculture, and increasing the cost input in the development of sightseeing agriculture. Furthermore, this paper specifically expounds the impact of the development of sightseeing and leisure agriculture on the development of rural economy, starting from the reality of rural economy, promoting the rapid development of sightseeing and leisure agriculture while promoting the progress of rural economy.
Research on the Crack Resistance and Bearing Capacity of Concrete Roadway Enhanced by Carbon Fiber Mesh and Carbon Fiber Short Cut Wire
Authors: Chen Lei
Published: July 2020

Shotcrete support technology can play a certain role in strengthening and anti-permeability of underground roadway. However, the lack of crack resistance and bending resistance seriously affects the function of shotcrete support. In this paper, the crack resistance and bearing capacity of underground concrete shotcrete layer were improved by means of high density carbon fiber mesh (CFM) embedded in prefabricated layer and carbon fiber short cut wires (CFSC) with different content of uniform cloth, which was focused on the synergistic strengthening mechanism between CFM and CFSC. The results show that the addition of high density CFM can significantly improve the bearing capacity of concrete shotcrete layer, but the improvement of crack resistance is not obvious. The addition of CFSC (with a content of 2% and a length of 3 mm) can significantly increase the initial crack load of concrete shotcrete, thus improving the crack resistance performance, but it has no obvious effect on the bearing capacity. Adding CFM and CFSC together can further significantly enhance the bearing capacity and crack resistance of concrete shotcrete layer and give full play to the synergistic enhancement effect between the two.
Study on the Development Effect Standard of Classified Well Groups for Polymer Flooding in Class II Reservoirs
Authors: Sun Xiangqi
Published: July 2020

Because of the development characteristics of the second type reservoir, the heterogeneity of the reservoir is obvious, and the development effect of polymer flooding in different well groups is quite different, which is not conducive to the adjustment and evaluation of later development. Therefore, it is necessary to classify the polymer flooding well groups in the second type reservoir according to the dynamic and static physical parameters, and evaluate the development effect of different types of polymer flooding well groups on this basis. By analyzing the dynamic and static data of polymer flooding blocks in type II reservoirs, this paper determines the influencing factors of well group classification evaluation, establishes the method of well group classification combined with grey correlation method and mathematical statistics analysis, uses reservoir numerical simulation technology to predict the development effect of polymer flooding for different types of well groups, gives the development effect standards of polymer flooding for different types of well groups, and plays a certain role in adjusting the development effect of polymer flooding in oilfields.