bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Urban Expansion Intensity on Urban Ecological Status Utilizing Remote Sensing and GIS: A Study of Semarang-Indonesia
Authors: Indrawati Like , Sigit Heru Murti B S , Rachmawati Rini , Aji Dwi Setyo
Published: March 2020

The rapid urban expansion will drive land-use conversion and cause substantial environmental and ecological impacts. The ability of remote sensing to record spatial and temporal data on the land surface with complete coverage has been proven effective for recognizing spatiotemporal changes in the regional eco-environment quickly. This study utilized Landsat TM / ETM + and Landsat-8 OLI remote sensing data to assess the effect of urban expansion intensity on the urban ecological status with the study area in Semarang, Indonesia. The method to measure urban expansion uses the urban expansion intensity index and to assess the urban ecological status using an integrated ecological index (IEI). The IEI generated from four parameters which include the degree of greenness (i.e. the soil adjusted vegetation index, SAVI), the moisture degree (i.e. the normalized difference moisture index, NDMI), dryness degree (i.e. the normalized difference soil index, NDSI) and built-up aggregation degree (i.e. the normalized difference built-up index, NDBI). Principal component analysis (PCA) is used to compress the four indicators to construct the index of ecological status and Pearson correlation analysis was used to determine the effect of urban expansion intensity on urban ecological status. The result showed that the urban land area increased by 38.98 km2 with an average expansion area of 3.9 km2 y-1 from 2005 to 2015. The index of urban expansion intensity during 2011-2015 increased about 2.1 times from 2005-2011. The pattern of deteriorating urban ecological status of the city of Semarang spreading towards the west, south, southeast, and east. The lowest integrated ecological index is in the central and northern parts of the city of Semarang. The extent of good and excellent urban ecological status continues to decline in a decade, on the contrary, the urban ecological status of poor and extremely poor increased. The negative linear relationship of the index of urban expansion intensity and urban ecological status shows that the intensity of urban expansion influences the urban ecological status in Semarang city.
Climate-based crop pattern determination using Standard Precipitation Index (SPI) and the Oldeman classification in Sangiran Site
Authors: Ahmada Benarifo , Rahmah Cahya Nur , Larasati Lia Amellya , Muchlis Luthfi , Qonita Maryam , Khoiruluswati Nur Medisyanning , Rohmah Siti , Karunia Rahayu Theresia Dhina , Nurjani Emilya
Published: March 2020

Sangiran Site is dominated by rainfed field. Climate parameters, especially rain intensity affects crop patterns. Farmers strongly depend on rain intensity to support productivity thus they need climate-based crop patterns. Sangiran Site is prone to drought hazard since the region has a limited access to groundwater, which is henced by deep well in the region. Drought becomes the main threat to agriculture within Sangiran. This study aims to analyse meteorological drought and crop pattern determination using the SPI and the Oldeman classification respectively. Rainfall data is derived from multi temporal CHIRPS data. A monthly time series with thirty consecutive years (1988–2017) was used to calculate the annual SPI. The annual SPI help to determine crop patterns which is suitable for the region. The results of the study show that angiran Site has monsoonal rainfall with one peak of dry season, and one peak of wet season. Rainfed field is at the highest risk when drought lasts for above four months. Climate based crop patterns with the Oldeman classification indicate that Sangiran Site is classified into type C2 which is adequate for two times palawija crops and one time paddy crops.
Temporal analysis of net radiation in the metropolitan area of San Luis Potosí - México using landsat 5 and 8 satellite images
Authors: Tristan A C , Ortiz J C M , Ovalle A G C , Cárdenas O R , Putri R F
Published: March 2020

The San Luis Potosí Valley is a basin situated in the municipalities of San Luis Potosí and Soledad de Graciano Sánchez belonging to the San Luis Potosí State and which make up the metropolitan area. This state is located in the north-central zone of México; it has a territorial extension of 64,165 m2 that represents 3.12% of the national territory. It is bounded to the north by the states of Coahuila, Nuevo Leon and Tamaulipas; to the south by Guanajuato, Queretaro and Hidalgo; to the east by Veracruz and to the west by Zacatecas and Jalisco. The analysis of the radiation capture phenomenon was carried out in the San Luis Potosí Metropolitan Area (ZMSLP). The study area is located between latitudes 22° 20′ 00″ and 22° 02′ 00″ north and longitudes 101° 12′ 00″ and 100° 44′ 00″ west. Net radiation is the phenomenon in which radiation fluxes interact between atmosphere and the earth’s surface. This phenomenon leads to processes such as evapotranspiration and photosynthesis. The net radiation analysis can be performed by three methods: (a) by using radiation monitoring stations, (b) by statistical models using data from meteorological stations such as temperature and relative humidity, and (c) by using satellite imagery. Since satellite images offer the possibility of analyzing large tracts of land, this method has been chosen to carry out the study using two images per year, one for the dry season and one for the rainy season between 1990 and 2017. The results show a considerable reduction in net radiation between the study periods, possibly due to the metropolitan area growth that impacts on the environment and therefore to the processes mentioned above.
Household waste management in Sukoharjo Village, Ngaglik District, Sleman Regency, Yogyakarta Special Region
Authors: Prakoso B S E , Pamungkas G S , Yusari T
Published: March 2020

Waste is an item that is considered to be unused and disposed of by the previous owner / user, but actually from the dumped part of the waste it can still be used if managed with the right procedure. The problem faced today is handling waste without going through the right management process. The community disposed of all the waste produced through the officers, buried in the garden or disposed of it wildly. This is found in Sleman Regency in general and in Sukoharjo Village specifically. This study aims to find out the characteristics of the waste management community in Sukoharjo Village; explain waste management in Sukoharjo Village; and examine the differences in waste management by the community in Sukoharjo Indah Housing with Banjarsari Hamlet . The method used in this study is a survey method. Survey is an investigation by using questionnaires for collecting data. Data collection was carried out by observation and interview of 76 respondents. The results, waste management model differences in the two regions due to the differences in household characteristics, such as income level and the land ownership to burn trash. On the other hand, the trash also requires management to avoid direct way disposed to landfill, by making use reduction, reuse, and recycling. However, waste management in both areas is reach the phase of reduction. This is due to the lack of socialization of waste management in the two regions, especially in Banjarsari Hamlet RT 06 surveyed had never held socialization.
Solar suitability map for office buildings using integration of remote sensing and Geographical Information System (GIS)
Authors: Omar R C , Wahab W A , Putri R F , Roslan R , Baharuddin I N Z
Published: March 2020

The rapid growth and urbanization of metropolitan regions has resulted to greenhouse gasses and global warming. The primary anthropogenic greenhouse gas emissions are coal dioxide, CO2, which is produced by natural operations such as cement manufacturing, deforestation and combustion of fossil fuels. This could have a major, damaging impact on human well-being. Energy requirements are anticipated to raise by a ratio of 1.5 to 3.0 by 2050, leading to an ever-increasing rise in carbon dioxide emissions. As rising carbon emissions have become a growing issue, there is a need to reduce carbon emissions. Many countries in the world are aiming at increasing the use of renewable energies and improving energy efficiency in urban and rural areas while utilizing the economic growth potential of the low-carbon sector. Among renewable energy sources such as wind and solar energy, solar energy is one of the oldest, cleanest, and most reliable renewable energy sources. Over the years, numerous methods for estimating solar radiation on a horizontal plane have been developed. In this study, the satellite dataset with the aid of GIS technology was used to generate solar suitability maps for the study area. With the integration of satellite images, spatial datasets, and GIS tools, the best location to set up solar collectors such as photovoltaic and concentrated solar power can be determined.
Agriculture development of Lampung Province based on agropolitan zonation
Authors: Rahmah C N , Purnomo A D , Amalia R D , Putri R F
Published: March 2020

Lampung Province is one of provinces in Indonesia which has a huge agriculture potential. Lampung’s sectoral contribution to gross domestic product (GDP) is predominantly from agriculture sector which makes up to 30% of the total Lampung GDP in 2017. The high agricultural contribution supports Lampung to surpass national economic growth in 2011 – 2017. Lampung is one of Indonesia’s major producer of a wide variety of agricultural products and commodities which include palm oil, cassava, rice, and chili pepper. However, the agriculture potential is not managed properly, thus agriculture sector shows a declining trend on Lampung regional GDP. This research aims to determine zonation of agropolitan area to promote agriculture development in Lampung Province. We use quantitative method by retrieving secondary data of GDP, agriculture commodities, and road map derived from Statistics of Lampung Province and Open Street Map (OSM) respectively. Analysis of the GDP data using Location Quotient (LQ) and Krugman Specialization Index (SI), and analysis of agropolitan zonation using geographic information system (GIS). The result indicates that agriculture development using agropolitan zonation is strongly affected by the percentage of agriculture shares on GDP and the distribution of road network across Lampung Province.
Nitrogen presence diagnosis in the Media Luna water spring, Rioverde-Cd. Fernández, San Luis Potosí, México
Authors: Pérez L A , Tristán A C , Barragán M L , Ovalle A G C , Putri R F
Published: March 2020

Potential water pollution not only changes water quality, it also threatens human health, economic development and social prosperity. This is the reason why it was carried out the analysis of La Media Luna water spring and the surrounding soil by means of a sample. The water spring is located in the municipalities of Rioverde and Cd. Fernandez belonging to the Middle Zone of the San Luis Potosi State, Mexico. The location coordinates are as follows (393791.987 E, 2417785.435 N). Water and soil samples were taken at a depth of 15 to 30 cm at each km of the canals to the north and south from the centre of the water spring, in which the nitrogen concentration was analysed by means of a UV-visible spectrophotometer. The water sampling evaluation was supplemented using geospatial techniques to observe the spread behavior and the dispersion of ammoniacal nitrogen, nitrates, pH and electrical conductivity. The objective of this research project was to identify the nitrogen concentration in the form of ammoniacal nitrogen and nitrate in order to know the impact of anthropogenic activities, the contributions of agrochemicals and fertilizers, and their possible consequences to the water spring.
Differences in adolescent knowledge about Generation Planning (GenRe) based on the characteristics of adolescents in the Ngepring Family Planning Village
Authors: Budiman L S , Listyaningsih U
Published: March 2020

Adolescent reproductive health in Indonesia so far still has problems that need to be addressed. The high birth rate of the age group of 15-19 years shows the low understanding of adolescents about reproductive health regarding family planning. Concerning adolescent behaviour such as early marriage trends, premarital sex, and drug abuse encourage the National Population and Family Planning Agency to implement Generation Planning (GenRe) Program to prepare family life for adolescents. The very diverse characteristics of adolescents in the Ngepring Family Planning Village lead to the assumption that it will lead to differences in adolescent knowledge about GenRe. This study aims to determine differences in adolescent knowledge about GenRe based on the characteristics of adolescents in Ngepring. Methods of data collection through interviews 123 adolescents with questionnaires. The results of the interviews were processed by parametric difference test using Independent Samples T-Test and One-Way ANOVA with SPSS. The variable of GenRe knowledge that is most affected by the characteristics is knowledge of Maturing Marriage Age, Three Basic Risks of Adolescent Reproductive Health and Small, Happy, Prosperous Family. This raises assumption that delivery of information needs to pay attention to the characteristics so that it is right on target.
Hydrochemistry temporal variation of Anjani Underground River, Jonggrangan Karst, Java Island, Indonesia
Authors: Pratama A D , Adji T N , Dwiputra D S
Published: March 2020

Anjani underground river was one of the biggest water resource in Jonggrangan Karst. The objective of this research was to describe hydrochemical temporal variation which was expected to assist in defining the aquifer conditions that recharge Anjani underground river in more detail. Sampling was carried out for one year covering dry and wet seasons, as well as the flood events. The hydrochemical analysis was conducted based on dissolved major ion concentration and physicochemical properties. In addition, SIcalcite and log PCO2 were calculated to understand the temporal variation of aggressiveness on calcite mineral. The results showed that all water samples performed HCO3-Ca type. The chemical constituent in water varied temporally which showed high during dry season and decreased during wet season. The high chemical constituent during dry season was caused by the domination of slow-flow (diffuse) so the water had a longer residence time in aquifer, allowing water-rock interaction to be more intensive. Meanwhile, the low dissolved constituent during wet season was caused by input from quick-flow that changed water-rock interaction into dilution by precipitation process. Generally, all water samples was saturated with respect to calcite, except during flood events. One of the factors that affected this condition was CO2 supply from the allogenic river that allowed the dissolution process to be more intensive.
The effects of hydrodynamic process and mangrove ecosystem on sedimentation rate in Kendal coastal area, Indonesia
Authors: Risanti A A , Marfai M A
Published: March 2020

The Coastal Area of Kendal Regency is subjected to continually changing morphodynamic processes. The density of mangroves contributes to the extent of accretion, sediment distribution, and high surface elevation. The study aimed to identify the effects of hydrodynamics on sedimentation, calculate the sedimentation rate, and analyze the significance of mangrove ecosystems in shaping this rate. Located on the west side of Bodri River, the research area includes a mangrove ecosystem directly facing the open water. This quantitative research involved analysis and validation of hydrodynamic parameters, quantification of sedimentation rate, identification of mangrove species, and calculation of the Importance Value Index (IVI) of mangrove at each growth stage. Parameters in November-February represented intensive hydrodynamic processes with the highest monthly average detected in February, meaning that sediment movement is also the most intensive in this month. The lowest sedimentation rate was 0.1501 mg/cm2/day, while the highest was 23.4938 mg/cm2/day. Rhizophora apiculata and Avicennia alba were the two mangrove species growing in the area. A. alba had the highest relative dominance score in the community, as indicated by its IVI. Mangrove density and sedimentation rate showed a directly proportional relationship in Plot 3 at two growth stages, namely, sapling and seedling.
The potential of delta ecosystem in North Coast of Java in reducing CO2 emissions
Authors: Kusumaningrum P B , Haryono E
Published: March 2020

Global warming causes more carbon dioxide (CO2) emissions. The mangrove forest is one of the world’s largest carbon sinks, as it is capable of storing and absorbing CO2 more than other forests. This research aims to determine carbon storage and CO2 sequestration at various zones of mangrove forests on the Wulan Delta, i.e. pond, river, and coastal zone, also determine the potential of delta ecosystem in North Coast of Java in reducing CO2 emissions with Wulan Delta as the sample. Systematic and non-destructive sampling method was used by measuring the Diameter at Height Breast (DBH) of mangrove trees with a diameter of >5 cm inside plot areas of 10 m x 10 m each, and the measurement result was then calculated based on an allometric equation. The mangrove forest of Wulan Delta has the above-ground of carbon density 245.578 ton C/ha, root carbon density of 100.778 ton C/ha, and soil carbon density of 42,991.169 ton C/ha. It sums up to the total carbon storage of 9,171,845.27 ton C and CO2 sequestration of 33,660,672.12 ton CO2 with an annual sequestration value of 1,530,030.55 tons CO2/year. The CO2 sequstration results are then compared with the delta in North Coast of Java with extrapolation method. The results obtained that Delta in North Coast of Java can absorb CO2 national emissions in 2018 by 3.416x10−6 CO2/year.
Estimation of suspended sediment concentrations in the Rhine River using Landsat Satellite Images
Authors: Sutari C A T , Van der Perk M , Middelkoop H
Published: March 2020

The traditional methods for measuring water quality and suspended sediment concentrations (SSC) are time-consuming and often do not give the spatial and temporal detail needed for assessment of the water quality and sediment transport. The determination of the suspended sediment concentrations using remote sensing through the main channel and tributaries of Rhine River can provide valuable information to assess the spatial and temporal of the suspended sediment. The main objective of this study is to estimate the suspended sediment concentrations (SSC) using Landsat satellite images. This study developed a method of quantifying SSC based on Landsat imagery and corresponding SSC data from the International Commission for the Protection of the Rhine (IKSR) and Dutch Rijkswaterstaat from 1995 to 2016. The model was built using the ratio of logarithmic transformation of a red/green band and logarithmic transformation of SSC based onin-situsampling measurements. The SSC model works well and shows satisfactory performance. Landsat satellites (Thematic Mapper (TM), Multi-Spectral Scanner (MSS), Enhanced Thematic Mapper (ETM), Operational Land Imager (OLI)) explained an acceptable result accuracy.
Slope stability analysis using Universal Distinct Element Code (UDEC) method
Authors: Roslan R , Omar R C , Putri R F , Wahab W A , Baharuddin I N Z , Jaafar R
Published: March 2020

Slope stability analysis was conducted using the Universal Distinct Element Code (UDEC) technique in this research. This technique stimulates the spread of stress waves in the jointed rock mass owing to dynamic loading caused by the blast. Simulation is a vital component of the slope stability analysis, as it generates a model called discontinuum capable of simulating the movement of fragments owing to the burst of production. Besides, the discontinuous codes used in this analysis may duplicate the entire method of fragmentation of the rock from fracture to fragment throw. This discontinuous analysis can also simulate joints and porosity attributes in a rock mass.
Landslide Susceptibility Zone using Frequency Ratio Method in Karangkobar Catchment, Merawu Watershed, Banjarnegara District, Central Java Province
Authors: Radjah V Y G , Suryatmojo H , Ngadisih
Published: March 2020

Karangkobar catchment is located in the upstream area of Merawu watershed, classified as one of the most critical watershed in Indonesia. Land use change from forested area to agricultural land has changed the hydrological process in the catchment. A huge landslide disaster has occurred at the end of 2014 and causing 95 people deaths. It is important to have a landslide susceptibility map for disaster risk mitigation in this area. The purpose of this study is to apply the frequency ratio method to analysis the landslide susceptibility in Karangkobar catchment. Actual landslide data is obtained from the results of field survey. Frequency ratio method is used to assess the landslide susceptibility using 70% of total landslides data while 30% is used for model validation. The results shown that the highest FR value is found in the distance from the road at range of 0-25 m, distance from the river at range of 100-125 m, flat curvature and garden land use. The broad percentage of low landslide susceptibility is 38%. moderate susceptibility is 48% and high susceptibility is 14%. The results of validation for landslide susceptibility showed that the resulting susceptibility model is very effective for assessing the landslide susceptibility.
Livelihood strategies of farmer households in the face of changing weather patterns: a case study from Sangiran Region
Authors: Budiman L S , Adlina L , Aisyah D A N , Irfan M , Diadasa N Q , Zain N A , Aliyya R R , Capilano A J , Rofi A
Published: March 2020

Java Island is the region where agriculture plays an important role in the economic activity of Indonesia. Nevertheless, the changing weather pattern in Sangiran has affect the cropping patterns, time of planting, production, and quality of the agriculture. Climate change affects the agricultural production loss between 5 - 20 %, while the long-term impact is the absence of farmers working on dry land. This sort of thing recently happens in Sangiran region which is a granary in Central Java because of the adaptation of the community. The purpose of this study was to determine the household livelihood strategies of farmers in the face a changing weather pattern in the Sangiran region. This research uses descriptive quantitative and qualitative approaches (mix method) in Sangiran region with multi-stage random sampling technique. The results of the research show that farmer households in Sangiran region face a changing weather pattern. Coping strategies that the farmers do while their facing changes in rainfall patterns are selling assets or property, money loan, reduce daily consumption, and change jobs. Strategies that the farmer households do to cope with the loss of assets are applying for a loan to a financial institution and working for someone else.
Online transportation workers in Palembang City: context and characteristics
Authors: Saputra Wahyu , Rum Giyarsih Sri , Joko Pitoyo Agus
Published: March 2020

Online transportation has become a necessity for people in Palembang City in particular. Palembang City is the only city in South Sumatra Province that has online transportation services. The existence of these services is related to the existence of disruptive innovations in the field of transportation services. Transportation which so far has only been based on conventional, has now changed to being based online. The purpose of this study is to describe the characteristics of online transportation workers in the city of Palembang. The research method used is quantitative with a descriptive approach. Data were collected by means of a survey of 384 respondents. Data analysis was performed using descriptive statistics. The results showed that online transportation workers in Palembang were dominant at a young age with a range of 18-28 years. Male gender is more dominant, mostly unmarried, migrant status originating from various regions in Sumatra and Java. Their education level is predominantly high school / vocational school with income of more than Rp 3,000,000. Their vehicle ownership status is private vehicle status.
Label free detection of uric acid using Si nanowire PH sensor
Authors: Lin Suhua , Wang Jing , Lin Yilin , Wang Xiaohua
Published: March 2020

In this study, we successfully apply a silicon nanowire FETs biosensor for detection of uric acid according to pH change. The pH sensing experiments of the silicon nanowire FETs shows that average sensitivity of 42mV/pH. We show that silicon nanowire FETs configured as pH sensors can be used for the quantitative detection of uric acid at concentration as low as 2.4mg/dL. The sensor shows a good linearity (R2 = 0.99) and sensitivity (60mV/mM) in the concentration range of 3-8mg/dL, with less than 300 sec response time. These results demonstrate that silicon nanowire FETs based biosensor can potentially be served as the diagnosis tool for general clinical examinations.
One-pot Synthesis of Multifunctional PAM@FeNPs Composite Microspheres
Authors: Wang Jun , Wang Jinke
Published: March 2020

Multifunctional composite microspheres are with variety of applications. In this study, one-pot dot polymerization synthesis was utilized to construct the polyacrylamide@Fe3O4 nanoparticles (PAM@FeNPs) composite microspheres. This composite microspheres featured as uniform size, great magnetic property, extremely stable visible and near-infrared autofluorescence produced by glutaraldehyde crosslinking. In conclusion, this study provides an important insight into the preparation of multifunctional composite microspheres.
Effect of micro-arc oxidation time on coating formation of AZ91 magnesium alloy in silicate electrolyte
Authors: Chen Xianming , Fan Yingying
Published: March 2020

The micro-arc oxidation behavior of AZ91 magnesium alloy in silicate alkaline electrolyte was studied. The effects of micro-arc oxidation time on film formation and microstructure were investigated and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), emission spectrometry (ICP) and salt spray test. The results show that oxidation time has an important effect on the surface morphology, thickness, phase structure and corrosion resistance of micro-arc oxidation film. With the increase of treatment time, the surface roughness and pore size increased. The acid ion (SiO3
2-) in electrolyte plays an important role in the formation of phase in the early stage of micro-arc oxidation, and the formation rate of MgO is dominant in the later stage. The corrosion rate decreases first and then increases with the increase of treatment time, and the corrosion rate of the sample processing 30min is lower under our technological conditions.
Influence factors of the chitosan degradation by pawpaw protease
Authors: Wang Qingyu , Shi Liang , Shen Yukai , Chen Xin , Chen Weidong
Published: March 2020

The pawpaw protease is used to degrade chitosan to prepare a low molecular weight chitosan-reducing sugar.The effect of temperature, pH value, reaction time and enzyme addition on the degradation of chitosan was investigated by single factor experiment with the reducing sugar concentration of the degradation solution as the index. The experimental results show that with the increase of the amount of enzyme added and the prolongation of the reaction time, and the degradation rate of chitosan increased and the concentration of reducing sugar increased. As the increase of pH and reaction temperature, the concentration of reducing sugar first increases and then decreases. The optimal conditions for chitosan degradation is 4.1 of the pH value, 42 °C of the reaction temperature, 1.4 h of the reaction time, and enzyme addition amount is 30 U/mg. Under the above conditions, the reducing sugar concentration reaches 1.57 g/L, and the rate is 15.7%.
Experimental study on municipal sludge rotary deep dewatering device
Authors: Yin Fengjiao , Zhao Gaiju , Wang Shouquan , Jiang Bin , Shi Yongchun
Published: March 2020

In view of the problem of drying high-humidity and high-viscosity sludge, it is analyzed in the water characteristics and drying characteristics of municipal sludge, optimizing the design of key components of ordinary rotary cylinder dryer and conducting industrial simulation experiments. The results show that: the self-cleaning and dispersing rotary cylinder dryer has higher heat exchange efficiency, smaller discharge particles and better drying effect than ordinary rotary cylinder dryer, which is a useful exploration for the research, development and popularization of municipal sludge deep dewatering process.
The determinants of energy consumption in China: a spatial panel data approach
Authors: Cao Huashen , Xu Yanli
Published: March 2020

As the second largest country of energy consumption around the world, China is facing an increasing pressure on energy-saving and emission-reduction. However, there is little research to study the spatial features and determinants of China’s energy consumption. This paper uses province level data in China from 2006 to 2016, and spatial panel model to analyze the determinants of energy emissions in China. The results indicate that the provincial energy consumption has a certain spatial autocorrelation, however, which is not strong. Regression results show that industrial development, economic level and financial development have significantly positive effects on energy consumption.
Overview of advanced oxidation technology based on sulfate radical in water treatment
Authors: Wang Junfei , Zhang Yongli
Published: March 2020

with the rapid development of industry and agriculture, the pollution of organic pollutant wastewater to the environment is becoming more and more serious. This paper introduces the classification of traditional water treatment method and advanced oxidation method, introduces their mechanism, advantages and disadvantages, and puts forward some research directions.
Study on the influence of waste residue of mixing station, slag and water slag on the strength of cement mortar
Authors: Hu Lizhi , Wang Shu , Wang Chan , Bao Ming , Wu Yuanyuan
Published: March 2020

In their paper. In this paper, the influence of the waste residue of the mixing station on the strength of cement mortar was studied. And the influence of the different content of the waste residue of the mixing station, slag and water slag on the strength of cement mortar was studied to get the optimal proportion. The study showed that when the mass ratio of the waste residue of mixing station, slag and water slag is 3:3:4 and 3:2:5, the synergistic effect of the three materials can be fully exerted, the grinding characteristics of the waste slag of the mixing station can be effectively improved, and the hydration activity of the waste slag of the mixing station can be improved.
Low cycle fatigue properties of 7050-T7451 aluminum alloy under different strain ratios
Authors: Tong Dihua , He Yuhuai , Hu Benrun , Chen Bo , Zhao Yanguang
Published: March 2020

The low cycle fatigue properties of 7050-T7451 aluminum alloy was studied. The low cycle fatigue properties of 7050-T7451 aluminum alloy at three strain ratios R = -1, 0.02, and 0.5 were measured by axial strain control method on MTS electro-hydraulic servo testing machine. In this research, the relationship between cyclic stress and strain at strain ratio R = -1 and the average stress relaxation effect of R = -1, 0.05 were given. The equivalent strain model was used to draw the strain-life curve for low cycle fatigue life data. The results show that under different strain ratios of 7050-T7451 aluminum alloy, the same strain amplitude in the high strain region leads to approximate fatigue life, and the effect of the strain ratio is only reflected in the low strain region.
Effect of extrusion routes on thermal stability of pure titanium processed by equal channel angular pressing
Authors: Wang Hongfei , Ban Chunyan , Qin Tipeng , Zhao Nannan , Liu Sitong , Kang Yiyao , Cui Jianzhong
Published: March 2020

Thermal stability of samples deformed by equal channel angular pressing (ECAP) using route BC and B135 was studied. The new route B135 was developed by defining 135° clockwise rotation of samples in each pass. After ECAP processing, samples were heat treated at different temperatures for a period of time. The effect of the two different routes on thermal stability of the ECAPed samples was investigated in detail. Electron backscatter diffraction was used to detect the processes of both recovery and recrystallization during thermal processing. Also, the effect of extrusion route on thermal stability of the deformed samples was further investigated by microhardness measurements.
Research on Rural Community Construction with Modern Rammed Earth Materials
Authors: Chen Zhenya , Guo Yu , Zhang Lingqing , Yan Jing , Fu Wenfeng , Wan Jiangjun , Tang Xiaohong
Published: March 2020

The soil exists in the vast countryside. Rammed earth materials are an important part of the growth process of rural dwellings. With the emergence of the homogenization of architectural style and the lack of cultural atmosphere of rural characteristics in the construction of beautiful countryside, the development and application of modern rammed earth materials will help the future construction of rural communities. Taking rammed earth dwelling houses in Sichuan as the research object, this paper constructs the livability evaluation system of rammed earth community, analyses the evaluation of residents’ satisfaction, and thus obtains the optimization strategy of modern rammed earth dwelling houses. From the theoretical perspective of "Ternary mutualism", the relationship between modern rammed earth materials and rural communities is mutually beneficial, that is, modern rammed earth materials are the natural foundation, charm display window and practice platform of rural communities, and rural communities are the embodiment of the value of modern rammed earth materials, protection continuation and multiple innovation. Based on this, the construction path of modern rammed earth materials in rural communities is proposed, in order to provide reference for the construction of rural communities using modern rammed earth materials. The research results show that modern rammed earth material, as a unique construction material, is conducive to the construction of rural communities in harmony with the natural ecological environment of the local landscape, and plays a role in the protection and inheritance of local culture.
Study on the Microstructure and Properties of Al/Cu Laser Filled Solder Joint
Authors: Wang Long , Hu Dean , Cheng Donghai , Chen Yiping , Dai Changqing , He Kai , Chen Yufu , Liao Feilong
Published: March 2020

Using IPG-YLS-4000 fiber laser to weld T2 copper plate and LY16 aluminum alloy plate, using Zn-10%Al flux cored wire as filler material, the microstructure of the joint was observed and analyzed by SEM and EDS, and the effects of laser power, welding speed and welding line energy on the mechanical properties of the joint were studied. The results show that the joints are mainly divided into copper side brazing area, weld center area and aluminum side fusion welding area. Among them, there are two interface reaction layers composed of intermetallic compound (IMC) in the copper side brazing area, the first layer is CuZn compound in the form of strip, and the second layer is Al2Cu phase in the form of shoot. The central area of the weld is mainly composed of massive α-Al phase and branched β-Zn phase. The tensile strength of the joint increases first and then decreases with the increase of laser power, welding speed and welding line energy. The thickness of IMC layer grows linearly with the increase of line energy. The best process parameters: when the laser power is 2200 W, the welding speed is 0.9 m/min, the welding line energy is 1446.67 J/cm, the IMC layer thickness is 10.11 μm, and the tensile strength reaches the maximum value, 252.6 MPa.
Preparation of low molecular weight chitosan by pawpaw protease
Authors: Zhang Yongli , Shi Liang , Chen Wenjing , Chen Xin , Chen Weidong
Published: March 2020

Pawpaw protease was used to degrade chitosan, and then obtained low molecular weight chitosan and reducing sugar in this study. According to the orthogonal experiment on the degradation of chitosan by pawpaw protease, the effects of temperature, pH value, reaction time and enzyme dosage on the decomposition efficiency of chitosan were investigated with the concentration of reducing sugar in the degradation solution as the index. The experimental results show that the optimal conditions for the degradation reaction are: the pH value of 4.1 and the reaction temperature of 42 °C, the reaction time of 1.4 h and the amount of enzyme of 30 U/mg, the concentration of reducing sugar in the degradation solution of 1.57 g/L and the yield of 15.7%.
Study on hot deformation behaviour and microstructure of Zr-4 alloy
Authors: Zhou Xuan , Wang Kelu , Li Xin , Gao Xiayun , Zhong Mingjun , Feng Rui
Published: March 2020

The isothermal compression experiment of Zr-4 alloy was accomplished by using Gleeble-3500 thermomechanical simulator. The hot deformation behaviour at the strain rate of 0.001~10s-1 and the deformation temperature of 750~1000°C was researched. The characteristics of flow stress were studied. The result is that the flow stress has a great influence on the deformation temperature and the strain rate. Based on the experimental data, the strain rate sensitivity map (m) was established. Through microstructure observation, the zones at lower m value are mainly flow localization (750 °C/10s-1) and kink (950 °C/10s-1). The zones at higher m value are mainly spheroidization. The result is that at strain rate of 0.01~0.1s-1/deformation temperature of 900~1000 °C is the suitable deformation parameter of Zr-4 alloy.
Mechanical properties and microstructure of coordination toughened epoxy based composites
Authors: He Yunyi , Wang Ruocheng , Wang Zhao , Kang Hongwei , Zhang Chenxi , Jin Haiyun , Gao Naikui
Published: March 2020

In this paper, toughening epoxy based composites were fabricated, the mechanical properties were measured and the microstructure was observed, the performance changes of epoxy casting system under different components were compared and analysed, coordination effect of multi-toughened was also investigated. Results showed that, the toughening agent and fumed silica as toughening fillers had the best strengthening and toughening effect on epoxy matrix with the addition of 4wt.% and 3wt.% respectively. Finally, by combining the different influence mechanism of the two fillers on the matrix, the comprehensive properties of the epoxy casting insulating materials were further improved. The results showed that the synergistic effect was obtained when the two fillers were blended with 3 wt.% toughener and 1 wt.% fumed silica. The tensile strength and impact strength were 67.42MPa and 13.69kJ/m2, which were 67.51% and 37.15% higher than those of pure epoxy.
Drying Experiment and Drying Model Analysis of Dehydrated Sludge Particles
Authors: Zhao Gaiju , Yin Fengjiao , Liang Xi , Yuan Dongling , Geng Wenguang , Wang Luyuan , Sun Rongfeng
Published: March 2020

A sludge drying experiment was conducted with dehydrated sludge particles as the research object, and the effects of temperature and particle size on sludge drying characteristics were discussed. The results show that the average drying rate of sludge can be increased by increasing the drying temperature and decreasing particle size of sludge, that is, the drying process of dehydrated sludge particles is controlled by internal migration. According to Fick’s second law, the simplified diffusion model of sludge drying is obtained by regression of experimental data, the simulation results obtained by the simplified diffusion model are in good agreement with the experimental results, which can well reflect the drying process of sludge particles and provide technical basis for the control of dehydrated sludge particles drying process.
Study on preparation of chito-oligosaccharide by cellulase hydrolysis
Authors: Chen Xin , Li Gaofeng , Dong Pengcheng , Sun Huili
Published: March 2020

By using cellulase enzymatic hydrolysis preparation to obtain low molecular weight chito-oligosaccharide. The conditions for the hydrolysis of chitosan by cellulase were studied by single factor experiment. The effects of temperature, pH value, reaction time and enzyme dosage on the decomposition efficiency of chitosan were investigated.The conclusions from the experiment are as follows: the optimum conditions for the preparation of chito-oligosaccharide by cellulase hydrolysis are reaction temperature of 50 °C, pH of 4.8, enzymatic hydrolysis time of 3.5 h, the enzyme dosage of 50 U/mg, in this case its economic benefits is greatest.
The fragmentation of thin-walled Q235 steel shell under explosion
Authors: Wei Jifeng , Du Zhixin , Zheng Yonghui , Zhang Liang , Lv Zhenbin
Published: March 2020

The fragmentation of a shell filled with explosive is quite valuable for evaluating the killing ability of improvised explosive device. A typical explosive device with Q235 steel shell and TNT explosive is chosen to study the fragmentation of thin-walled structure. With sand recovery method, experiments are conducted to get fragments with the mass above 0.1g. G-S formula shows a better agreement with experimental results when predicting average fragment mass than Mott formula. Further researches show that shell thickness and length-diameter aspect ratio have great effect on the fragmentation of shell. Average fragment mass increases exponentially and total fragment number decreases exponentially when shell thickness increases, while average fragment mass remains almost unchanged and fragment number grows linearly when length-diameter aspect ratio increases. These results are very helpful for whenever academic study or real application.
Effect of Oxidized Polyethylene Wax on Curing Process of Powder Coatings
Authors: Wang Wenxue , Wang Yujue , Han Yuying , Liu Ziliang , Wang Chuanxing
Published: March 2020

In this paper, differential scanning calorimetry (DSC) was used to analyze the reaction kinetics of powder coatings. The effects of oxidized polyethylene wax (OPEW) on the curing process of powder coatings were investigated by exploring the curing process of OPEW-Owt% and OPEW-8wt% powder coatings. The Tgof OPEW-8wt% powder coating was 57.1 °C, which was greater than the Tgof OPEW-Owt% powder coating, indicating that OPEW increased the storage stability of the system. The apparent activation energy (Ea) of the two powder coatings was investigated by the Kissinger and Doyle-Ozawa equations. The Crane empirical equation was used to calculate the curing reaction order (n) of the two powder coatings, and the curing kinetics was discussed. The Eaof OPEW-0wt% was 64.35 kJ⋅mol-1, and the Ea of OPEW-8wt% was 60.95 kJ⋅mol-1, indicating that OPEW could promote the curing reaction.
Orthogonal experimental study on preparation of chitosan oligosaccharide based on cellulase hydrolysis
Authors: Chen Xin , Xu Feng , Dong Shaofeng , Li Gaofeng , Sun Huili
Published: March 2020

The conditions of enzymatic hydrolysis of chitosan by cellulase were studied by orthogonal experiments. The effects of temperature, pH, reaction time and enzyme dosage on the decomposition efficiency of chitosan were investigated and the following conclusions were obtained by experiments: the major and minor relationship between the factors affecting the conversion of chitosan oligosaccharide prepared by cellulase hydrolysis is temperature > pH > time. The optimum conditions are as follows: at the reaction temperature of 50 °C, the pH of 4.8 and the hydrolysis time of 3.5 h. Under these reaction conditions, the content of reducing sugar is the highest, which is 1.59 mg⋅mL-1, and the economic benefit is the best.
Optimized Design of Aircraft Control Surface Driving Structure Based on Shape Memory Alloy
Authors: Li Fan , Li Yixuan , Zhao Jianhui
Published: March 2020

A driving structure using the shape memory alloy (SMA) wire to deflect an aircraft control surface was designed in this study. Instead of changing angle mounts or other conventional methods for changing the attitude angle of aircraft control surfaces, this driving structure drew on the existing idea of smart material SMA driven aileron deformation. The main contribution of this study is the optimization of the rib design inside the control surface: ribs with different numbers of hinged sections were evaluated and the location of the SMA wires were adjusted, to improve the range of achievable deflection angles and the ability of the rib to withstand aerodynamic force. Simulation results show that the use of a three-section or four-section rib effectively improves the aerodynamic effect of the control surface over the use of a two-section rib, especially under the action of larger aerodynamic forces; compared with a two-section rib, a four-section rib provides a deflection angle as much as 20% larger under aerodynamic pressure.
Sensitivity Analysis of Factors Influencing the Stability of Loess Landslide
Authors: Mu Peng
Published: March 2020

Sensitivity analysis is used to check and analyze the factors that have a greater impact on the stability of the landslide, and determine the most sensitive factors that affect the stability of the landslide. At present, the sensitivity analysis of the factors affecting the stability of loess landslides in high intensity seismic regions has not been reported. In this paper, taking a loess landslide in Wenchuan earthquake area as an example, the sensitivity of its stability factors is analyzed by using the improved grey correlation method, which provides the basis for the treatment and design of loess landslide.
Multifunctional modification of viscose fiber using plant extracts formulations
Authors: Li Huimin , Yu HuSheng
Published: March 2020

Some plant extracts with specific functions have been used to integrate with textiles, which can not only endowing the fabric with certain functions, but also accord with the concept of environmental protection and sustainable development. In this paper, codonopsis powder and thyme essential oils microcapsule were added to viscose spinning fluid. The obtained viscose fiber with various functions, such as antibacterial activity, anti-mould activity and anti-mites activity. In addition, the durability are also more than 20 washes. The multifunctional viscose fiber has a more extensive application prospect.
Effect of calcination time on degradation of landfill leachate by Fe-Co-Ru-Ce / γ-Al2O3 catalytic wet oxidation system
Authors: Wang Qingyu , Zhang Honghua , Zhang Yongli
Published: March 2020

The landfill leachate was used as the target pollutant, and the degradation was carried out by catalytic wet oxidation. The heterogeneous catalyst Fe-Co-Ru-Ce/γ-Al2O3 was prepared by impregnation method. The calcination time was set to 1.5, 3, 4.5, 6, 7.5 h respectively, the catalyst was calcined at a constant temperature for a set time to prepare five catalysts, and the influence of the calcination time on the activity of the catalyst was investigated. The results showed that when the calcination time was 3 h, the activity of the catalyst reached the maximum. At this time, the COD removal rate and decolorization rate of the treated water were 78.1% and 60.4%, respectively.