VNU Journal of Science: Earth and Environmental Sciences最新文献

{"title":"Study on Adsorption of Nickel and Methylene Blue in Aqueous Solution by Magnetic Carboxylate-Rich Carbon","authors":"Doan Van Dat, Nguyen Hoai Thuong, Tran Thi Kieu Ngan, Le Thi Thanh Nhi, Dao My Uyen, Tran Thi Huong, Cong Hong Hanh, Le Van Thuan","doi":"10.25073/2588-1094/vnuees.4586","DOIUrl":"https://doi.org/10.25073/2588-1094/vnuees.4586","url":null,"abstract":"In this study, magnetic carboxylate-rich carbon material (Fe3O4@CRC) was synthesized via a low-temperature carbonization method and applied as an adsorbent for adsorption of Ni(II) ions and methylene blue (MB) in aqueous solution. The synthesized Fe3O4@CRC was characterized by various techniques (XRD, FTIR, FE-SEM, TEM, EDX, VSM, and BET). The adsorption kinetics, isotherms, thermodynamics, and the effects of key adsorption factors, including the pH value, initial adsorbate concentration, contact time, adsorbent dose and temperature were investigated in detail. The results showed that Fe3O4@CRC exhibited a high adsorption capacity for MB and Ni(II) with the maximum adsorption capacity of 187.26 mg/g and 106.75 mg/g, respectively. The adsorption of MB and Ni(II) on Fe3O4@CRC was a spontaneous and endothermic process, and was best described with the first-order kinetic model, Freundlich (for MB) and Langmuir (for Ni(II)) isotherm models. In addition, Fe3O4@CRC could maintain a high adsorption capacity after many consecutive cycles. Therefore, the Fe3O4@CRC material can be used as a highly efficient adsorbent for the removal of heavy metals and dyes from wastewater due to the advantages of high adsorption performance, easy separation, and good reusability. \u0000 ","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116016901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Survey and Assessment of Willingness to Pay (WTP) for Reducing the Health and Environmental Risks of Vegetable Production Activities inBinh Chanh District, Ho Chi Minh City","authors":"Vu Thi Bao Ngoc, Thai Anh Hoa, Nguyen Thi Kim Thoa, Nguyễn Minh Kỳ","doi":"10.25073/2588-1094/vnuees.4472","DOIUrl":"https://doi.org/10.25073/2588-1094/vnuees.4472","url":null,"abstract":"The paper presents the current state of using pesticides and Willingness to Pay (WTP) to reduce vegetable producers’ health and environmental risks in Binh Chanh District, Ho Chi Minh City. This study used random sampling method by investigating 60 households (30 normal farm households and 30 VietGAP households). The main contents cover assessment on the impacts of using  pesticides, conducting WTP surveys to reduce health and environmental risks due to exposure to pesticides and analyzing marginal effects related to the Log - Lin regression model. Regarding the current, the normal vegetable producers tended to use more pesticides and exceed recommended doses compared to VietGAP group. The regression model explained 86,0 percent of the changes in farmers' WTP. The estimation results of the affecting factors to WTP showed that the variables such as agricultural promotion (X3), income (X4), amount of group I&II pesticides (X5), the frequency of exposure of group I&II pesticides (X7), and dummy variables GAP (GAP) were statistically significant (p<0,05). Therefore, the study proposed relevant solutions to reduce health and environmental risks in vegetable production for the safe use of pesticides.","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123862431","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diversity of Terrestrial Molluscs in Ngoc Son-Ngo Luong Nature Reserve, Hoa Binh Province (Mollusca: Gastropoda)","authors":"D. Sang, Nguyen Thanh Son, N. T. Hue, R. Devender","doi":"10.25073/2588-1094/vnuees.4569","DOIUrl":"https://doi.org/10.25073/2588-1094/vnuees.4569","url":null,"abstract":"Ngoc Son-Ngo Luong Nature Reserve composes of a large variety of natural habitats, such as limestone forest, limestone karsts, caves and isolated limestone hills. Therefore, this area is expected to have a high species diversity, especially for the terrestrial molluscs. A total of 56 species was recorded, of which 12 were recorded in Hoa Binh Province for the first time. The data on terrestrial molluscs in this study could be considered as a scientific basis to carry on systematic research. \u0000 ","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"60 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116906043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on Adsorption of Methylene Blue from Aqueous Solution by Biochar Derived from Mimosa Pigra Plant","authors":"N. X. Cuong","doi":"10.25073/2588-1094/vnuees.4582","DOIUrl":"https://doi.org/10.25073/2588-1094/vnuees.4582","url":null,"abstract":"Biochar from mimosa pigra was studied to remove methylene blue (MB) from aqueous solution. The properties of biochars were determined using Fourier Transform Infrared, scanning electron microscope, and Brunauer–Emmett–Teller. The biochar achieved the yield of 24.62 % at 500 oC pyrolysis. The specific surface area of ​​the biochar is 285.53 m2/g, the total pore size is 0.153 cm3/g and the ash content is 2.79%. The optimal dose of removing MB of the biochar is 5 g/L and the optimal pH is 2 - 10. MB removal reached over 80% in the first 30 min, followed by a stable period of 120 to 360 min reaching over 90% of removal. Maximum adsorption capacity reached 20.18 mg/g at 25 oC. MB adsorption data is suitable for kinetic models in order: Avrami > Elovich > PSO > PFO. The adsorption process may comprise physical and chemical adsorption andmultiple stages. \u0000 ","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122559557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of SAR Sentinel-1 Satellite for Air Emission Inventory from Rice Straw Open Burning in Hanoi","authors":"H. Le, N. V. Thanh, D. M. Phuong, H. Bằng, Nguyen Quang Hung, Dinh Manh Cuong","doi":"10.25073/2588-1094/VNUEES.4635","DOIUrl":"https://doi.org/10.25073/2588-1094/VNUEES.4635","url":null,"abstract":"Air emission inventory is an advance tool in application research of environmental field. Emission inventory can be conducted in different approaches, in which statistical data collection is considered to be a conventional way with relatively low reliability and delaying time. This study uses a methodology of extracting activity data of cultivation area and rice production employing SAR Sentinel-1 images in order to overcome the limitation of conventional method. Consequently, the data is utilized to estimate the total air pollutants emitted from rice straw open burning. Results show that integration of remote sensing data (SAR Sentinel-1 satellite) improves the seasonal spatial rice cultivated area and production distribution with high reliability. The study implies a considerable potential of satellite data for estimation of air emission from agriculture waste combusion due to its availability, real-time, and low cost features. Application for Hanoi in 2019 performs that an amount of 460 thousand tons of rice straw was burned, thus, created 542 thousand tons of CO2 (90%), 42 thousand tons of CO (7%), and other air pollutants of the rest 3%.","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"2011 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127367312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of Statistic Model and Backpropagation Neural Network to Analyzing and Forecasting Hydropower Dam Displacement","authors":"Bui Thi Kieu Trinh, Xiao Yangxuan, Chinh Van Doan, Do Xuan Khanh, Mai Dinh Sinh","doi":"10.25073/2588-1094/VNUEES.4529","DOIUrl":"https://doi.org/10.25073/2588-1094/VNUEES.4529","url":null,"abstract":"Horizontal displacement of Hoa Binh dam in operation phase was analyzed and then forecasted by using three methods: the multi-regression model (MTR), the Seasonal Integrated Auto-regressive Moving Average (SARIMA) and the Back-propagation Neural Network (BPNN). The monitoring data of the Hoa Binh Dam in 137 periods, including horizontal displacement, time, reservoir water level and air temperature were used for the experiments. The results indicated that all of these three methods could describe the real trend of dam deformation and achieve the required accuracy in short-term forecast up to 9 months. In addition, forecast results of BPNN had the highest stability and accuracy.","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116314967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of Green Nanocomposite to Adsorb Cadmium ion in Wastewater","authors":"H. Ha, T. D. Minh, H. M. Nguyet","doi":"10.25073/2588-1094/VNUEES.4564","DOIUrl":"https://doi.org/10.25073/2588-1094/VNUEES.4564","url":null,"abstract":"In the condition of industrialization, the water environment has been contaminated by industrial and agricultural waste as well as pharmaceutical residuals. These sources of waste water are usually treated efficiently prior to releasing into environment. This leads to a significant quantity of pollutants accumulated in water, threating seriously to human health. Among various detected pollutants, Cadmium and its compounds are considered as one of the most dangerous reagents. They can be released to the environment from different sources of waste, such as metal, alloy and metal plating, and Cd-Ni batteries, which clearly showed a danger to the human health. This work aims to develop a novel “green” material applied for highly efficient treatment of Cd (II). The concept “Green material” indicates the material which is composed of environmental-friendly compounds (non-toxic to human and organisms, degradable or biodegradable). The novel material C2H5OHSiO2/PANI (CSP) was synthesized using two-step procedure including functionalization of silicon oxide nanoparticles (SiO2) by polyaniline polymer (PANI) and dispersion of SiO2/PANI in ethanol under ultrasound sonication. All components of CSP including Silica, ethanol, PANI do not have negative effect on environment, thus they are applied in plenty of fields. CSP were successfully synthesized and characterized by several methods and techniques such as FTIR, SEM, TEM and BET analysis. Based on the practical data, the Cd (II) adsorption was followed by Langmuir adsorption isotherms, and the pseudo-second order adsorption kinetic. CSP has obtained the Cd (II) maximum adsorption capacity of 301.23 mgg, which is higher than the previous reported adsorbents. Cd (II) adsorption by CSP is desired at pH 6, reaction time of 150 min, initial concentration of Cd (II) as 300 mgL, CSP weight as 0.6 g. Adsorption data show that pH is one of the most important factor in Cd (II) adsorption due to the formation of surface complexes between Cd (II) and the functional groups of CSP such as hydroxyl group (OH), silanol (Si-OH), amine (– NH2), quinoid imine [C=N–] and benzenoid amine [–NH–].","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126408524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulation of the Hydrodynamic Field in Nhat Le Estuary, Quang Binh Province","authors":"N. Loc, Dang Dinh Thuc, Trang Vinh Quang","doi":"10.25073/2588-1094/VNUEES.4460","DOIUrl":"https://doi.org/10.25073/2588-1094/VNUEES.4460","url":null,"abstract":"Hydrodynamic field is the primary research problem of all studies on coastal estuarine areas. Over the years, there have been many studies on Nhat Le estuary's region (Quang Binh). Still, these studies have not focused on simulating the characteristics of the hydrodynamics of this area. This study presents the ability to apply a mathematical model to simulate hydrodynamic fields for the region of Nhat Le estuary and Quang Binh sea by constructing the MIKE 21 model set based on the actual measurement database by the Center for Environmental Fluid Dynamics implemented in 2018. Through the calculation scenarios under different conditions, the longshore current mainly consists of Southeast Northwest (especially with NE waves, the current direction is Northwest Southeast) with current speed mostly in the range of 0.1 0.4 m/s. In estuarine areas, river flows have complicated developments, including many component flows. In the dry season, the river flow is not strong and is dominated by changes in the tide phase, withdrawal in a day. There are days of high flood flow in the flood season, overwhelming the tidal currents; the maximum flow velocity at the door can reach more than 6 m/s. Waves in the southwest monsoon season are relatively small, about 0.25 0.6 m; while the waves in the Northeast monsoon season are quite large and very strong during the storm, but when the depth is about -3 to -4 m, the wave height decreases sharply, spreading to the door. In particular, when there are floods in the river, the waves that propagate through this depth will almost calm.","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115365083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ecological Characteristic of Grazing Vegetation and Capacity Food for the Large Cattle in Central Highland, Vietnam","authors":"Vũ Anh Tài, T. T. Van, B. Q. Tuấn, L. D. Hoang","doi":"10.25073/2588-1094/VNUEES.4528","DOIUrl":"https://doi.org/10.25073/2588-1094/VNUEES.4528","url":null,"abstract":"The Highland Central of Vietnam has a high potential for livestock development with a vast grazing areas include scrubs, grassland and some forest types. Currently, the livestock of the Central Highland has been facing with water shortage when dry season has prolonged from 4 to 6 months that make most of the plant communities stop growing. In order to develop livestock in the Central Highland, the ecological characteristics of the natural vegetation were gathered, including structure, seasonal rhythm and succession trend of each plant communities related to grazing. In this paper, the ecological characteristics of 11 natural ecological habitats and one artificial habitat were described. In addition, natural grazing vegetation includes five forests, three scrubs and three grasslands belonging to three bio-climate types (tropical monsoon moisture, tropical monsoon dry and sub-tropical monsoon moisture) and three ecological canopy types (evergreen, semi-deciduous and deciduous) were analyzed. The seasonal rhythm of each ecosystem affected the food resources for the cattle. In which, the main food was found in dry grasslands and scrubs in the rainy season while those habitats have not supported food considerable in the dry season. Thus, the cattle would get food from the moisture habitats in this period. The largest changes of food source ratios between rainy and dry seasons were found in Dak Lak and Gia Lai provinces, where the dry habitats are common. On contrary, the changing ratios at Kon Tum and Lam Dong provinces have been not much. Hence, these two provinces would support stably food for the large cattle during the year. However, when the density of the cattle head is too high, the natural food sources cannot adapt for the cattle requirement especially in the dry season. Thus, people must use the other sources such as planting, industrial food for cattle feeding. The density of the cattle also affected the ecological succession trend of each habitat. In normally, the forest would be changed to the scrubs and the scrubs would be changed to the grassland, and vice versa. In the first trend, it is positive but the second trend is negative. Because of high density of cattle, the negative ecological succession within ________ * Corresponding author. E-mail address: tai.botany@gmail.com https://doi.org/10.25073/2588-1094/vnuees.4528 V.A. Tai et al. / VNU Journal of Science: Earth and Environmental Sciences, Vol. 37, No. 1 (2021) 28-43 29 the natural vegetation related to the grazing in the Central Highland has been found at the western area of Dak Lak and Gia Lai provinces, and most areas of Kon Tum and Dak Nong provinces except the habitat along the boundary of the special used forest (national park, nature reserves). The positive succession would be found at all of the special used forest areas, Lam Dong province, Southeastern area of Dak Lak province, Central areas of Gia Lai province.","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114728345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics of late Miocene Lithofacies - Paleogeography in the Southeast Region of Hanoi Depression","authors":"Nguyen Thi Thao, T. Nghi, D. X. Thanh","doi":"10.25073/2588-1094/VNUEES.4633","DOIUrl":"https://doi.org/10.25073/2588-1094/VNUEES.4633","url":null,"abstract":"The characteristics of late Miocene lithofacies in the southeast region of Hanoi depression have been revealed on the basis of sedimentary evolution in relation to sea level change and tectonic movement. During late Miocene, global sea level change had created one depositional sequence and three sedimentary systems tract. The lowstand systems tract (LST) is characterized by 5 rhythms of alluvial lithofacies. These rhythms were represented by rough and humoc seismic wave fields. This environment was not favorable condition for coal formation. The transgressive systems tract (TST) was characterized by 6 transitional lithofacies rhythms. Each lithofacies rhythm consisted of 4 facies: the tidal flats sand facies of the bay, the mud facies of the river mouth lagoon, the coastal marshy mud facies creating coal and the bay greenish-gray clay facies. The pacing process involved changes in the local sea level caused by tectonic lift. Each tectonic subsidence phase took place at a very slow velocity, so it was compensated for fine-grained sediment creating marshy mud facies to develop mangroves on a large scale. It was a prerequisite to create thick coal seams distributed near the end of each rhythm. A part of highstand systems tract (HST) were eroded due to the improved folding process, creating an angular unconformity boundary with Pliocene-Quaternary sediments. However, after reconstracting of deformated section, it was clear that this system tract had only one rhythm including 2 facies: prodelta mud facies and alluvial fan sandstone facies.","PeriodicalId":247618,"journal":{"name":"VNU Journal of Science: Earth and Environmental Sciences","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121298276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}