Vietnam Journal of Science and Technology最新文献

Effect of rice husk morphology on the ability to synthesize silicon carbide by pyrolysis method 稻壳形态对热解法合成碳化硅能力的影响

Vietnam Journal of Science and Technology Pub Date : 2024-07-24 DOI: 10.15625/2525-2518/18511

Kieu Do Trung Kien, Hanh Ong Dieu, Khoi Nguyen Hoang Thien, Minh Huynh Ngoc

{"title":"Effect of rice husk morphology on the ability to synthesize silicon carbide by pyrolysis method","authors":"Kieu Do Trung Kien, Hanh Ong Dieu, Khoi Nguyen Hoang Thien, Minh Huynh Ngoc","doi":"10.15625/2525-2518/18511","DOIUrl":"https://doi.org/10.15625/2525-2518/18511","url":null,"abstract":"Silicon carbide (SiC) is a mineral with good technical properties and high economic value. However, the synthesis of SiC is expensive because it is synthesized at a high-temperature environment (above 1500oC). The synthesis of SiC from biomass can significantly reduce the synthesis temperature. One commonly used biomass material for synthesizing SiC is rice husk. However, the ability to synthesize SiC depends on the shape of the rice husk. The influence of the morphology of rice husk on the ability to synthesize SiC was studied in this study. Experimental results showed that the original rice husk would give better SiC formation capacity than the rice husk powder. The amount of SiC formed using the original rice husk when impregnated by sodium silicate solution and pyrolysis at 1200oC is 18.3% (wt%.). With rice husk powder, it is 15.12% (wt%.). The results of analysis of the mineral composition, functional groups, and morphologies by X-ray diffraction (XRD), Fourier Infrared Transform Method (FT-IR), and Scanning Electron Microscopy (SEM) found that the polymorphy of SiC is α-SiC and β-SiC. These minerals are the basis for SiC from rice husks, which can be applied as wear-resistant materials.","PeriodicalId":23553,"journal":{"name":"Vietnam Journal of Science and Technology","volume":"1 13","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141807291","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}

引用次数: 0

Green synthesis of nanostructured 1T/2H-MoS2 hybrid phase with polyol solvents and microwave heating 利用多元醇溶剂和微波加热绿色合成纳米结构 1T/2H-MoS2 混合相

Vietnam Journal of Science and Technology Pub Date : 2024-07-24 DOI: 10.15625/2525-2518/18507

Thi Minh Nguyet Nguyen, V. Vuong, Huu Huy Phuc Nguyen, Van Thang Le

{"title":"Green synthesis of nanostructured 1T/2H-MoS2 hybrid phase with polyol solvents and microwave heating","authors":"Thi Minh Nguyet Nguyen, V. Vuong, Huu Huy Phuc Nguyen, Van Thang Le","doi":"10.15625/2525-2518/18507","DOIUrl":"https://doi.org/10.15625/2525-2518/18507","url":null,"abstract":"Green synthesis approaches have attracted greatly of attention in recent years since they address the issues associated with sustainability than conventional synthesis methods. New research fields in green nanoscience are being developed as a result of the incorporation of green chemistry principles into nanoscience. In this paper, the successful microwave-assisted green synthesis of MoS2 nanoparticles in a single pot using polyol solvents such as ethylene glycol and glycerol is demonstrated. The coexistence of 1T and 2H phases in MoS2 nanomaterials was determined using advanced techniques such as XRD, Raman, XPS, and TEM images. The highest 1T proportion obtained was 84.5% when compared to the 2H phase. The reaction mechanism and the phase transition between 1T and 2H were described and illustrated. The role of polyol solvents in the practical synthesis of nano MoS2 under microwave heating is also evaluated and explained. Due to the ability of the metallic 1T phase to enhance electrical conductivity, it is believed that hybrid nanostructures exhibit superior electrochemical performance for energy storage and conversion applications.","PeriodicalId":23553,"journal":{"name":"Vietnam Journal of Science and Technology","volume":"58 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141808945","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}

引用次数: 0

Study on solidified material from dredged sediment, fly ash, and blended Portland cement using the response surface method 利用响应面法研究由疏浚沉积物、粉煤灰和混合硅酸盐水泥制成的固化材料

Vietnam Journal of Science and Technology Pub Date : 2024-07-24 DOI: 10.15625/2525-2518/18519

Tien-Dat Thai, N. Huynh, Tuyen Luu, Kien Kieu Do Trung, Nhi Nguyen Vu Uyen, Minh Do Quang

{"title":"Study on solidified material from dredged sediment, fly ash, and blended Portland cement using the response surface method","authors":"Tien-Dat Thai, N. Huynh, Tuyen Luu, Kien Kieu Do Trung, Nhi Nguyen Vu Uyen, Minh Do Quang","doi":"10.15625/2525-2518/18519","DOIUrl":"https://doi.org/10.15625/2525-2518/18519","url":null,"abstract":"Treating dredged sediment is a complex processing and ongoing challenge. To utilize dredged sediment for the landfill or construction purposes, a material fabricated from a mixture of dredged sediment, Portland cement, and fly ash, was cured under room temperature and hydrothermal condition at 180 °C and 0.9 MPa pressure for 16 hours. The response surface methodology was used to evaluate the compressive strength of the material, with the range of factors investigated being the dredged sediments/solid ratio (0.3-0.9), cement/fly ash ratio (2-4), and water/solid ratio (0.45-0.55). The fitting models offered an accurate and reliable match to the actual data. The optimum mix proportions of two curing conditions were obtained using total desirability function, meet multi-objective criteria. This result finger out hydrothermal curing significantly enhances treatment capacity of dredged sediment, with a lower CO2 emission in the mixture compared to ambient curing. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) were used to figure out the difference between the minerals formed in the material under two curing conditions, such as tobermorite.","PeriodicalId":23553,"journal":{"name":"Vietnam Journal of Science and Technology","volume":"58 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141808468","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}

引用次数: 0

comprehensive review of rock dust for soil remineralization in sustainable agriculture and preliminary assessment of nutrient values in micronized porous basalt rock from Nghe-An province, Vietnam 全面审查岩尘在可持续农业中的土壤再矿化作用，初步评估越南义安省微粉多孔玄武岩中的营养价值

Vietnam Journal of Science and Technology Pub Date : 2024-07-24 DOI: 10.15625/2525-2518/18544

Nguyen Hoang Thien Khoi, Nguyen Ngoc Tri Huynh, Nguyen Vinh Phuoc, Nguyen Khanh Son

{"title":"comprehensive review of rock dust for soil remineralization in sustainable agriculture and preliminary assessment of nutrient values in micronized porous basalt rock from Nghe-An province, Vietnam","authors":"Nguyen Hoang Thien Khoi, Nguyen Ngoc Tri Huynh, Nguyen Vinh Phuoc, Nguyen Khanh Son","doi":"10.15625/2525-2518/18544","DOIUrl":"https://doi.org/10.15625/2525-2518/18544","url":null,"abstract":"This review delves into the utilization of rock powder as a mineral-derived fertilizer to support soil remineralization in the context of sustainable agriculture. Soil remineralization has emerged as a key strategy for ensuring long-term soil fertility and reducing the dependency on synthetic fertilizers. This review critically assesses the methodological approaches applied in various studies, taking into account factors such as local rock mineralogy, soil conditions, crop types, and nutrient uptake by plants. The review covers a range of methods, including nutrient value analysis, assessment of nutrient release rates, crop cultivation experiments in both laboratory and field settings, and the resulting implications for soil remineralization. Additionally, we present findings from a preliminary study focusing on the nutrient content of basalt rock from Nghe-An Province, Vietnam. This experimental investigation is centered on the assessment of nutrient values in a specific porous basalt material, which has been processed into micro-nanometer particles using a high-energy ball mill, thereby enhancing nutrient release efficiency. The study employs a range of analytical techniques, including XRD, XRF, SEM/EDS, and ICP-MS, to quantify macro- and micro-nutrient compositions. While the basalt rock samples may exhibit limitations in providing macronutrients (such as K) compared to commercial azomite rock, they offer distinct advantages in furnishing secondary macronutrients (like Ca). This comprehensive analysis provides insights into the potential use of micronized basalt rock for soil remineralization.","PeriodicalId":23553,"journal":{"name":"Vietnam Journal of Science and Technology","volume":"52 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141807030","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}

引用次数: 1

Manufacturing of Al-Zr-Si master alloy from zircon concentrate 利用锆石精矿制造铝-锆-硅母合金

Vietnam Journal of Science and Technology Pub Date : 2024-07-24 DOI: 10.15625/2525-2518/18562

Huynh Cong Khanh, Ly Thai Phap, Do Thanh Toan

引用次数: 0

Zinc Oxide/Polypyrrole particle-decorated rod structure for NO2 detection at low temperature 用于低温检测二氧化氮的氧化锌/聚吡咯粒子装饰棒结构

Vietnam Journal of Science and Technology Pub Date : 2024-07-24 DOI: 10.15625/2525-2518/18528

Vu Thanh Dong, Pham Tien Hung, Le Duc Anh, Ly Quoc Vuong, Dang Duy Khanh, Nguyen Thi Huong

{"title":"Zinc Oxide/Polypyrrole particle-decorated rod structure for NO2 detection at low temperature","authors":"Vu Thanh Dong, Pham Tien Hung, Le Duc Anh, Ly Quoc Vuong, Dang Duy Khanh, Nguyen Thi Huong","doi":"10.15625/2525-2518/18528","DOIUrl":"https://doi.org/10.15625/2525-2518/18528","url":null,"abstract":"In this study, Zinc oxide (ZnO) nanoparticles with a size of about 50 - 70 nm were green-synthesized using tea leaves and ZnO/Polypyrrole (ZnO/Ppy) nanocomposites were obtained by ultrasonic-assisted chemical polymerization method using pyrrole monomer and the nanoparticles. The characterization of the materials is conducted using several analytical techniques, including Field Emission Scanning Electron Microscopy (FESEM) and X-Ray Diffraction (XRD) and Ultraviolet visible spectrum (UV-Vis).\u0000The synthesized PPy material exhibits have a rod-shaped structure, diameter ranging from 100 to 200 nm. The ZnO/PPy nanocomposite system, consisting of PPy rods surrounded by ZnO particles. The gas sensing characteristics of the materials have also been investigated by measuring their sensitivity, response time, and stability to NO2 at low temperature and different humidity. Notably, the material exhibits considerable sensitivity to NO2 gas at low temperatures and the parameters related to response and recovery times are relatively rapid. Furthermore, a potential gas-sensing mechanism based on changes in the width of the depletion region is proposed.","PeriodicalId":23553,"journal":{"name":"Vietnam Journal of Science and Technology","volume":"56 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141808958","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}

引用次数: 0

Synthesis of hydroxyapatite and strontium-substituted hydroxyapatite for bone replacement and osteoporosis treatment 合成用于骨替代和骨质疏松症治疗的羟基磷灰石和锶替代羟基磷灰石

Vietnam Journal of Science and Technology Pub Date : 2024-07-24 DOI: 10.15625/2525-2518/18533

Le Thi Bang, Nguyen Van Ha, Bui Duc Long, Nguyen T. Hong Nhung

{"title":"Synthesis of hydroxyapatite and strontium-substituted hydroxyapatite for bone replacement and osteoporosis treatment","authors":"Le Thi Bang, Nguyen Van Ha, Bui Duc Long, Nguyen T. Hong Nhung","doi":"10.15625/2525-2518/18533","DOIUrl":"https://doi.org/10.15625/2525-2518/18533","url":null,"abstract":"Hydroxyapatite (HAp) is an inorganic component exhibiting bioactivity similar to that of natural bone. However, it is not resorbed by osteoclasts during bone remodelling due to its lack of bio-resorption property. This can be enhanced by the substitution of other element presented in bone mineral. In this research work, hydroxyapatite (HAp) and strontium-substituted hydroxyapatite (Sr-HAp) were synthesized by a precipitation method. Calcium nitrate tetra hydrate [Ca(NO3)2•4H2O], disodium hydrogen phosphate (Na2HPO4), and Strontium nitrate [Sr(NO3)2] were used as Ca, PO4 and Sr sources, respectively. Molar ratio Ca/P=1.67 was used to synthesize HAp, where (Ca+Sr)/P=1.67 was used to synthesize strontium substituted-HAp (Sr-HAp). The reaction was carried out at room temperature. The results show that pure HAp and Sr-HAp were formed with nanometer-sized particles. Sr substitution in the HAp lattice results in an increase in both the lattice disorder and crystal aspect ratio. The results of in vitro bioactive testing using simulated bodily fluid also showed that both HAp and Sr-HAp have high bioactive, with the Sr-HAp sample having the greater bioactive. Therefore, HAp and Sr-HAp have great potential for biological applications.","PeriodicalId":23553,"journal":{"name":"Vietnam Journal of Science and Technology","volume":"43 20","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141809584","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}

引用次数: 0

Preparation and characterization of Lithium-stabilized Colloidal Silica as a silicate densifier for concrete surface treatment 将锂稳定胶体二氧化硅作为用于混凝土表面处理的硅酸盐致密剂的制备和特性分析

Vietnam Journal of Science and Technology Pub Date : 2024-07-24 DOI: 10.15625/2525-2518/18515

Hoang Thien Khoi Nguyen, Ngoc Tri Huynh Nguyen, N. Huynh, Khanh Son Nguyen

{"title":"Preparation and characterization of Lithium-stabilized Colloidal Silica as a silicate densifier for concrete surface treatment","authors":"Hoang Thien Khoi Nguyen, Ngoc Tri Huynh Nguyen, N. Huynh, Khanh Son Nguyen","doi":"10.15625/2525-2518/18515","DOIUrl":"https://doi.org/10.15625/2525-2518/18515","url":null,"abstract":"Enhancing the durability of concrete by safeguarding it against cracking and environmental deterioration is paramount. While silicate-based densifiers have been instrumental in shielding concrete surfaces from wear and environmental factors, the surging popularity of lithium silicate solutions faces a significant impediment due to the high cost of lithium, mainly attributed to its predominant use in manufacturing lithium batteries. To address this substantial challenge, an intriguing approach involves blending lithium silicate with colloidal silica, potentially offering a cost-effective and efficient solution for concrete surface treatment. This study delves into the feasibility of utilizing lithium-stabilized colloidal silica as a silicate densifier, focusing on their preparation, characterization, and efficacy in lab-scale applications. The results demonstrate that lithium-stabilized colloidal silica can heighten surface hardness while concurrently reducing porosity. However, it is worth noting that this approach presents particular challenges, particularly regarding preparation and water resistance, when compared to surfaces treated solely with lithium silicate. Addressing these hurdles holds promise for optimizing and enhancing lithium-stabilized colloidal silica and advancing the concrete surface treatment field in future research endeavours.","PeriodicalId":23553,"journal":{"name":"Vietnam Journal of Science and Technology","volume":"33 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141810106","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}

引用次数: 0

Synthesis of Polybenzoxazine as an environmentally friendly adhesive material from cardanol and post-consumer PET source 利用万丹醇和消费后 PET 源合成环保型粘合剂材料聚苯并恶嗪

Vietnam Journal of Science and Technology Pub Date : 2024-07-24 DOI: 10.15625/2525-2518/18526

Xuan Viet Cao, Viet Chat Luong, Khanh Tuong Huynh, Uy Lan Du Ngoc

引用次数: 0

A snapshot of bacterial endophytes isolated from the roots of Vetiver grass (Chrysopogon zizanioides) grown at Bien Hoa airbase, Dong Nai province 从同奈省边和空军基地种植的香根草（Chrysopogon zizanioides）根部分离的细菌内生菌快照

Vietnam Journal of Science and Technology Pub Date : 2024-05-23 DOI: 10.15625/2525-2518/19395

Thi Lan Anh Vu, Thi Nhan Nguyen, Thi Ha Thu Dang, The Hai Pham, Quoc Dinh Nguyen, Thi Thuy Huong Ngo, Van-Tuan Tran

{"title":"A snapshot of bacterial endophytes isolated from the roots of Vetiver grass (Chrysopogon zizanioides) grown at Bien Hoa airbase, Dong Nai province","authors":"Thi Lan Anh Vu, Thi Nhan Nguyen, Thi Ha Thu Dang, The Hai Pham, Quoc Dinh Nguyen, Thi Thuy Huong Ngo, Van-Tuan Tran","doi":"10.15625/2525-2518/19395","DOIUrl":"https://doi.org/10.15625/2525-2518/19395","url":null,"abstract":"Vetiver grass (Chrysopogon zizanioides) with a strong root system has been widely used for environmental pollution treatment. Recently, this grass has been cultivated at Bien Hoa airbase to mitigate dioxin concentration in the contaminated soil. Bacterial endophytes have been recognized to play key roles in plant growth promotion and responses of plant hosts to environmental factors. However, a beneficial association between endophytic bacteria and Vetiver grass root system grown in dioxin-contaminated soil has not been elucidated. In the present study, we isolated sixteen endophytic bacterial strains from the roots of Vetiver grass. The results of DNA sequencing of the 16S rRNA gene revealed that these culturable bacterial endophytes belong to 9 species of different genera. Four strains, including Klebsiella variicola B1, Enterobacter cloacae B4, Enterobacter kobei B6, and Enterobacter cloacae B11, produce high amounts of indol acetic acid (IAA). Strains K. variicola B1 and E. cloacae B4 also produce phytase and phosphatase to dissolve phytate and phosphate, respectively. These strains were selected to evaluate their abilities in promoting the growth of tomato plants as a model. After 28 days of inoculation with the tested strains through the roots, tomato plants grew 19% to 22% faster than the control plants. Conclusively, this study shows for the first time the successful isolation of endophytic bacteria from the roots of Vetiver grass cultivated in dioxin-contaminated soil, and some culturable bacterial strains exhibit as promising candidates for plant growth promotion.","PeriodicalId":23553,"journal":{"name":"Vietnam Journal of Science and Technology","volume":"19 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141107558","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}

引用次数: 0