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Synthesis and characterization of PMMA-grafted-ZrO2 hybrid nanoparticles PMMA 接枝-ZrO2 混合纳米粒子的合成与表征
Pub Date : 2023-12-15 DOI: 10.15625/2525-2518/16991
Linh Nguyen Thi Dieu, Dung Nguyen Thi Kim, Thang Dam Xuan, Tham Do Quang
In this study, we reported a facile synthesis and the characterization of PMMA-grafted ZrO2 hybrid nanoparticles from original ZrO2 (oZrO2) nanoparticles. The synthesis process included of three steps: (i) modification of nano ZrO2 with a vinyl silane agent, (ii) graft copolymerization of methyl methacrylate (MMA) monomers and modified ZrO2 (mZrO2) nanoparticles, and (iii) extraction of homo PMMA to obtain the final product of PMMA-g-ZrO2 (gZrO2) nanoparticles. Fourier transform infrared (FTIR) spectra and thermogravimetric analysis (TGA) of mZrO2, oZrO2, and gZrO2 indicated that the silane coupling agent was grafted onto oZrO2 nanoparticles. FTIR spectra of gZrO2 indicated PMMA had been successfully grafted onto the surface of ZrO2 nanoparticles. Using TGA method, the PMMA grafting content onto ZrO2 nanoparticles was evaluated as 9.03 wt.%. The electron microscopy (SEM) images of gZrO2, mZrO2, and oZrO2 indicated that their primary particle size and shape were almost unchanged after modification processes, their particle size was in the range from 50 nm to 140  nm. XRD analysis showed the monoclinic crystalline structure of three kinds of ZrO2 nanoparticles (nanocrystals). The organic gZrO2 nanoparticles can be a better candidate as an opacifier additive for polymer nanocomposites or acrylic bone cement.
在这项研究中,我们报道了一种从原始 ZrO2(oZrO2)纳米粒子中简便合成 PMMA 接枝 ZrO2 混合纳米粒子的方法及其特性。合成过程包括三个步骤:(i) 用乙烯基硅烷剂改性纳米 ZrO2;(ii) 甲基丙烯酸甲酯(MMA)单体与改性 ZrO2(mZrO2)纳米粒子接枝共聚;(iii) 萃取均质 PMMA,得到最终产品 PMMA-g-ZrO2(gZrO2)纳米粒子。mZrO2、oZrO2 和 gZrO2 的傅立叶变换红外光谱(FTIR)和热重分析(TGA)表明,硅烷偶联剂接枝到了 oZrO2 纳米粒子上。gZrO2 的傅立叶变换红外光谱表明 PMMA 已成功接枝到 ZrO2 纳米粒子表面。使用 TGA 方法评估了接枝到 ZrO2 纳米粒子上的 PMMA 含量为 9.03 wt.%。gZrO2、mZrO2 和 oZrO2 的电子显微镜(SEM)图像表明,改性后它们的原始粒径和形状几乎没有变化,粒径范围在 50 纳米到 140 纳米之间。XRD 分析表明,三种 ZrO2 纳米粒子(纳米晶体)均为单斜晶系结构。有机 gZrO2 纳米粒子可以更好地用作聚合物纳米复合材料或丙烯酸骨水泥的不透明添加剂。
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引用次数: 0
Modelling carbon dioxide gas emission from Notopterus chitala fish ponds by stella software 利用 stella 软件模拟鳙鱼池塘的二氧化碳气体排放
Pub Date : 2023-12-15 DOI: 10.15625/2525-2518/16746
Van So Nguyen, Anh Tuan Le
The rapid development of the areas of ​​Notopterus chitala fish ponds in Hau Giang province in recent years has raised a question about greenhouse gas emissions, in the form of total carbon dioxide equivalents (CO2e). There are many parameters that affect greenhouse gas emissions in a fish pond, such as amount of feed, dissolved oxygen (DO), chemical oxygen demand (COD) in the water, pH, water temperature, windy velocity and sunlight reaching the pond surface. In this study, a System Thinking, Experimental Learning Laboratory with Animation, shortly called as Stella is applied as a visual programming language for system dynamics modelling in order to find the relationship between simulated CO2 and measured CO2 in Notopterus chitala fish pond. Three ponds were used for measuring average pH, temperature, feeds, DO, COD and phytoplankton inside the ponds while windy speed and light intensity data were collected from a Weather Station nearby. The results of model calibration and validation showed that the Stella 8.0 can be used as predictable tool for the change in time of CO2 emission during 240 days of fishing. Model can help fishing farmers to adjust the quantity of feeds and control the water quality in their Notopterus chitala fish ponds to reduce greenhouse gas emissions appropriately.
近年来,后江省鳙鱼池塘面积的快速发展引发了以总二氧化碳当量(CO2e)为形式的温室气体排放问题。影响鱼塘温室气体排放的参数有很多,如饲料量、溶解氧 (DO)、水中化学需氧量 (COD)、pH 值、水温、风速和到达池塘表面的阳光。在本研究中,应用了系统思维、带动画的实验学习实验室(简称为 Stella)作为系统动力学建模的可视化编程语言,以找出鳙鱼池塘中模拟的二氧化碳与测量的二氧化碳之间的关系。使用三个池塘测量池塘内的平均 pH 值、温度、饲料、溶解氧、化学需氧量和浮游植物,同时从附近的气象站收集风速和光照强度数据。模型校准和验证结果表明,Stella 8.0 可用作预测 240 天捕鱼过程中二氧化碳排放时间变化的工具。该模型可帮助渔业养殖户调整饲料投放量和控制鱼塘水质,从而适当减少温室气体排放。
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引用次数: 0
Eco-friendly method of biocementation for soil improvement and environmental remediation in the context of Viet Nam: a state-of-the-art review 在越南采用生态友好型生物固化法进行土壤改良和环境修复:最新进展综述
Pub Date : 2023-12-15 DOI: 10.15625/2525-2518/18516
Ngoc Tri Huynh Nguyen, Pham Huong Huyen Nguyen, Hoang Thien Khoi Nguyen, Khanh Son Nguyen
Scientists have been using microorganisms to improve soil strength and durability through a process called biocementation. This technique involves inducing mineral precipitation to form a cement-like material that enhances soil properties. Biocementation has been successful in various applications, including soil stabilization, erosion control, and groundwater remediation. Researchers are optimizing nutrient concentrations and ratios to create a favorable environment for microbial activity and promote efficient mineral formation. Different microorganisms have varying abilities to induce mineralization, and cycle treatments have shown promise in stimulating biomineralization processes. Biocementation is a sustainable and eco-friendly technique that can stabilize and immobilize contaminants in soil and groundwater, preventing the spread of pollutants. Despite these challenges, biocementation holds great potential for innovative soil improvement and environmental remediation. Recent studies, experiments, testing devices, and results from research groups in the world and Vietnam in recent years were reviewed to gain insight into this promising approach. Ongoing research aims to develop cost-efficient and sustainable methods for large-scale production and application of biocementing agents. Further research is needed to uncover the intricate mechanisms and identify optimal strategies for applications and environmental conditions.
科学家们一直在利用微生物,通过一种名为 "生物固结 "的过程来提高土壤强度和耐久性。这种技术包括诱导矿物质沉淀,形成一种类似水泥的材料,从而增强土壤性质。生物固结技术在各种应用领域都取得了成功,包括土壤稳定、侵蚀控制和地下水修复。研究人员正在优化养分浓度和比例,以创造有利于微生物活动的环境,促进矿物的有效形成。不同的微生物诱导矿化的能力各不相同,循环处理在刺激生物矿化过程方面已显示出良好的前景。生物固化是一种可持续的生态友好型技术,可以稳定和固定土壤和地下水中的污染物,防止污染物扩散。尽管存在这些挑战,生物固结在创新性土壤改良和环境修复方面仍具有巨大潜力。为了深入了解这一前景广阔的方法,我们回顾了近年来世界各国和越南研究小组的最新研究、实验、测试设备和成果。目前正在进行的研究旨在开发具有成本效益和可持续的方法,以大规模生产和应用生物固化剂。还需要进一步研究,以揭示其复杂的机理,并确定适用于各种应用和环境条件的最佳策略。
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引用次数: 0
Optical properties of circular photonic crystal fibers filled with carbon tetrachloride 填充四氯化碳的环形光子晶体光纤的光学特性
Pub Date : 2023-12-15 DOI: 10.15625/2525-2518/17045
Hoang Trong Duc, Le Tran Bao Tran, Tran Ngoc Thao, C. V. Lanh, Nguyen Thi Thuy
In this work, the dispersion properties and nonlinear properties of circular photonic crystal fibers were improved by a combination of carbon tetrachloride infiltration into the core and modification of the air hole diameters d1 and d2 of rings in the cladding. The quantities such as dispersion, effective mode area, nonlinear coefficient, and low confinement are analyzed in detail. Based on the survey results, two photonic crystal fibers with optimal optical properties were proposed which are beneficial for supercontinuum generation. The first fiber with Ʌ = 1.0 µm, d1/Ʌ = 0.6, has an all-normal dispersion of –10.785 ps/nm.km at a pump wavelength of 0.985 µm. The high nonlinear coefficient of 581.795 W–1.km–1 and the low confinement loss of 3.904 dB/m are also achieved with this fiber. SC broadband under the influence of soliton is expected to be generated when using the second fiber (Ʌ = 2.0 µm, d1/Ʌ = 0.3) with flat and low anomalous dispersion at the pump wavelength of 1.3 µm.
在这项研究中,通过在纤芯中渗入四氯化碳和改变包层中环的气孔直径 d1 和 d2,改善了环形光子晶体光纤的色散特性和非线性特性。详细分析了色散、有效模式面积、非线性系数和低约束等量。根据研究结果,提出了两种具有最佳光学特性的光子晶体光纤,它们都有利于超连续产生。第一种光纤的Ʌ = 1.0 µm,d1/Ʌ = 0.6,在泵浦波长为 0.985 µm 时的全常色散为 -10.785 ps/nm.km。这种光纤还具有 581.795 W-1.km-1 的高非线性系数和 3.904 dB/m 的低约束损耗。如果使用第二根光纤(Ʌ = 2.0 µm,d1/Ʌ = 0.3),在 1.3 µm 的泵浦波长处具有平坦而低的反常色散,则有望在孤子影响下产生 SC 宽带。
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引用次数: 0
Assessment of the role of ACC deaminase, IAA, and siderophore-producing bacteria isolated from Spratly Islands on the growth of Brassica juncea on the coral sand 评估从南沙群岛分离的 ACC 脱氨酶、IAA 和产苷细菌对珊瑚沙上甘蓝菜生长的作用
Pub Date : 2023-11-20 DOI: 10.15625/2525-2518/18867
Vu Thi Quynh Chi, Nguyen Viet Hiep, Le Thi My Hao, Nguyen Quang Hai, Do Thi Kim Anh, Huong Pham, Than Van Hau, Nguyen Cong Viet, Ngo Thi Xinh, Nguyen Thi Loi, Bui Dang Thanh
Root endophytic and rhizosphere bacteria play a significant role in enhancing plant tolerance and promoting growth by producing 1-aminocyclopropane-1-carboxylate (ACC) deaminase, indole-3-acetic acid (IAA), and siderophore. These bacteria have been isolated and screened from 45 plants’ roots and rhizosphere soil samples of 19 types of plants which are growing on 8 floating islands in Spratley Islands, Viet Nam. In which, 3 root endophytic bacteria strains were selected and identified to be Agrobacterium tumefaciens, Pseudomonas plecoglossicida, and Klebsiella aerogenes from roots of Scaevola taccada, Barringtonia asiatica (L.) Kurz, and Carica papaya, respectively. Correspondingly, 3 rhizosphere bacteria strains were selected and identified to be Bacillus velezensis, Bacillus aryabhattai, and Bacillus velezensis from rhizosphere soils of Canavalia maritima (Aubt) Thouars (C. obtusifolia DC.), Cucumis sativus, Heliotropium foertherianum, respectively. These strains were found could increase the germination rate of Brassica juncea’s seeds and 20-day-old fresh biomass, compared to the control treatment in the same condition of 10‰ saline watering. When these bacterial strains were combined as an inoculant, they indicated the same result on coral sand. Thus, the addition of selected endophytic and rhizosphere bacteria is efficient in improving the coral sand environment to enhance food crops’ development in the Spratly Islands.
根部内生菌和根瘤菌通过产生 1-氨基环丙烷-1-羧酸(ACC)脱氨酶、吲哚-3-乙酸(IAA)和嗜苷酸,在增强植物耐受性和促进生长方面发挥着重要作用。这些细菌是从生长在越南南沙群岛 8 个浮岛上的 45 种植物根部和 19 种植物根圈土壤样本中分离和筛选出来的。其中,从 Scaevola taccada、Barringtonia asiatica (L.) Kurz 和 Carica papaya 的根部筛选并鉴定出 3 株根内生细菌,分别是农杆菌、褶皱假单胞菌和气生克雷伯氏菌。相应地,从 Canavalia maritima (Aubt) Thouars (C. obtusifolia DC.)、Cucumis sativus、Heliotropium foertherianum 的根瘤土壤中筛选并鉴定出 3 株根瘤菌,分别为 Velezensis 杆菌、Bacillus aryabhattai 杆菌和 Velezensis 杆菌。研究发现,在 10‰盐水浇灌的相同条件下,与对照处理相比,这些菌株能提高芥蓝种子的发芽率和 20 天的新鲜生物量。当这些细菌菌株作为接种剂混合使用时,它们在珊瑚沙上的效果相同。因此,添加精选的内生菌和根瘤菌可有效改善珊瑚沙环境,促进南沙群岛粮食作物的生长。
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引用次数: 0
Heterotrophic nitrifying bacteria from activated sludge in DHS reactor for ammonium removal of natural rubber processing wastewater treatment DHS 反应器中活性污泥的异养硝化细菌用于天然橡胶加工废水处理的氨去除
Pub Date : 2023-10-20 DOI: 10.15625/2525-2518/17141
Tran Minh Duc, Phan Thi Thanh Thuy, Nguyen Thi Huyen, Nguyen Lan Huong
Two heterotrophic nitrifying bacterial strains, D2 and D7 were isolated from an activated sludge of sponges in a laboratory-scale downflow hanging sponge reactor. Both strains exhibited efficient ammonium removal ability over a wide range of ammonium loads. At the initial concentration of 100 mg/L, NH4+-N was completely degraded within 20 h by both strains. When the initial concentration was increased to 200 mg/L, the NH4+-N removal efficiency was 99.6 % within 20 h by the strain D2 and 61.3 % by the strain D7. In natural rubber processing wastewater, the ammonium removal efficiencies of strain D2 and D7 were 38 % and 99 % with the initial N-NH4+ concentration of 280 and 380 mg/L after 88 h, respectively. The 16S rRNA gene sequence of D2 and D7 showed the highest similarity to the Pseudomonas aeruginosa and Glutamicibacter nicotianae, respectively. This is the first report to demonstrate the ability to remove ammonium in NRPW by ​heterotrophic nitrifying bacteria isolated from activated sludge in DHS reactor.
在实验室规模的下流式悬挂海绵反应器中,从海绵活性污泥中分离出两种异养硝化细菌菌株 D2 和 D7。这两株菌株在广泛的氨负荷范围内均表现出高效的氨去除能力。初始浓度为 100 mg/L 时,两种菌株都能在 20 小时内完全降解 NH4+-N。当初始浓度增加到 200 mg/L 时,菌株 D2 在 20 小时内对 NH4+-N 的去除率为 99.6%,菌株 D7 为 61.3%。在天然橡胶加工废水中,当初始 N-NH4+ 浓度为 280 mg/L 和 380 mg/L 时,菌株 D2 和 D7 在 88 h 后的氨去除率分别为 38 % 和 99 %。D2 和 D7 的 16S rRNA 基因序列分别与铜绿假单胞菌和烟酸谷氨酸杆菌的相似度最高。这是首次报道在 DHS 反应器中从活性污泥中分离出的异养硝化细菌去除 NRPW 中氨氮的能力。
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引用次数: 0
Studies on hepatoprotective effects of Vietnamese medicinal plants 越南药用植物的保肝作用研究
Pub Date : 2023-10-20 DOI: 10.15625/2525-2518/17426
Ngoc Khanh Pham, Katarina Bauerova, Nguyen Manh Cuong
The liver is a major organ of the human and animal body, playing an important role in metabolism, detoxification and immunomodulation. When liver tissue is damaged, liver function will decrease, leading to liver diseases such as liver fibrosis, cirrhosis, and liver cancer. Medicinal plants and natural products have provided a source of new drug candidates for the prevention and treatment of liver diseases. This review is based on scientific publications on Vietnamese plants investigated for their hepatoprotective activity during the period from 1998 to 2022. 51 medicinal plants, 38 phytoconstituents, and 8 hepatoprotective herbal formulations of Vietnamese-origin have been reported to protect the liver from the harmful effects induced by hepatotoxins, typically CCl4 or paracetamol. Each plant's information, including its botanical name, family, part of the plant used, local name, chemical constituents, extracts or fractions used, dosage, model used, parameters obtained, histopathology, and results of hepatoprotective studies, is displayed. Also discussed is the possible mechanism of action of these hepatoprotective plants.
肝脏是人和动物身体的主要器官,在新陈代谢、解毒和免疫调节方面发挥着重要作用。当肝脏组织受损时,肝功能就会下降,导致肝纤维化、肝硬化和肝癌等肝脏疾病。药用植物和天然产品为预防和治疗肝病提供了新的候选药物来源。本综述基于 1998 年至 2022 年期间有关越南植物保肝活性研究的科学出版物。据报道,51 种药用植物、38 种植物成分和 8 种越南原产保肝草药配方可保护肝脏免受肝毒素(通常是四氯化碳或扑热息痛)的危害。每种植物的信息,包括其植物学名称、科属、使用的植物部分、当地名称、化学成分、使用的提取物或馏分、剂量、使用的模型、获得的参数、组织病理学以及肝脏保护研究的结果,均有展示。此外,还讨论了这些保肝植物可能的作用机制。
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引用次数: 0
Antioxidant, angiotensin converting enzyme inhibitory and anthelmintic activities of bark essential oil of Cinnamomum bejolghota (Buch.-Ham.) Sweet from North East India 印度东北部 Cinnamomum bejolghota (Buch.-Ham.) Sweet 树皮精油的抗氧化、血管紧张素转换酶抑制和驱虫活性
Pub Date : 2023-10-20 DOI: 10.15625/2525-2518/17346
B. Gogoi, K. J. Tamuli, Snigdha Saikia, Neipihoi Lhouvum, M. Bordoloi, Hemanta K. Sarma
Cinnamomum bejolghota (Buch.-Ham.) Sweetisa traditional anthelmintic and cardiotonic medicinal plant. The essential oil extracted from the bark of C. bejolghota was characterized by gas chromatography-mass spectrometry and 28 constituents were identified. Monoterpenoids were found to be dominating chemical constituents with α-terpineol (18.57 %) as the major component of the essential oil. The antioxidant activity of the essential oil was evaluated by DPPH radical, β-carotene bleaching and reducing power assay methods. The essential oil showed in-vitro dose-response hindering activity against angiotensin-converting enzyme with an IC50 value of 33.43 ± 0.46 µg/mL.The essential oil also exhibited potent anthelmintic property in-vitro against Caenorhabditis elegans with an ED50value of 80.53 ± 3.57 µg/mLin adult mortality assay. The inhibitory activity of essential oil against larval development assay showed an ED50value of 72.40 ± 2.68 µg/mL against C. elegans larva. Further, the egg hatching assay using C. eleganseggs demonstrated an ED50 value of 68.27 ± 3.51 µg/mL with this essential oil. Thus, the ethnomedicinal claim has been validated for the bark essential oil, which provides an excellent scope for the development of the C. bejolghota bark essential oil as novel herbal antihypertensive and anthelmintic agents.
Cinnamomum bejolghota (Buch.-Ham.) Sweetisa 是一种传统的驱虫和强心药用植物。采用气相色谱-质谱法对从 C. bejolghota 树皮中提取的精油进行了表征,并确定了 28 种成分。发现单萜是主要的化学成分,α-松油醇(18.57 %)是精油的主要成分。精油的抗氧化活性通过 DPPH 自由基、β-胡萝卜素漂白和还原力测定法进行了评估。精油对血管紧张素转换酶具有体外剂量反应阻碍活性,其 IC50 值为 33.43 ± 0.46 µg/mL。精油还在体外对秀丽隐杆线虫(Caenorhabditis elegans)具有有效的驱虫特性,在成虫死亡率试验中的 ED50 值为 80.53 ± 3.57 µg/mL。精油对幼虫发育实验的抑制活性显示,其对秀丽隐杆线虫幼虫的 ED50 值为 72.40 ± 2.68 µg/mL。此外,在使用象鼻虫进行卵孵化试验时,该精油的 ED50 值为 68.27 ± 3.51 µg/mL。因此,树皮精油的民族药用价值得到了验证,这为将 C. bejolghota 树皮精油开发成新型草药降压药和驱虫药提供了良好的发展空间。
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引用次数: 0
Fracture analysis in 2D plane strain problems for composite materials containing hard inclusions and voids using an extended consecutive-interpolation quadrilateral element 使用扩展连续插值四边形元素分析含有硬夹杂物和空隙的复合材料二维平面应变问题中的断裂分析
Pub Date : 2023-10-20 DOI: 10.15625/2525-2518/18456
Binh Hai Hoang, V. S. Lo, B. Tran, T. T. Truong
This paper investigates fracture mechanics in particle-reinforced composites by using the extended finite element method enhanced by the consecutive-interpolation quadrilateral element. These composite materials have discontinuous boundaries such as cracks, voids, holes, and soft inclusions. And the extended consecutive-interpolation quadrilateral element (XCQ4) is employed to model these boundaries in two-dimensional linear elastic deformation problems. XCQ4 combines the enrichment functions in the traditional extended finite element method with the consecutive interpolation on a 4-node quadrilateral element. This element uses both nodal values and averaged nodal gradients as interpolated conditions. In fracture analysis, the stress intensity factors (SIFs) are important parameters that must be defined.  In this study, the values of SIFs at the crack tips are evaluated with the help of the interaction integrals approach. The obtained numerical results are compared with other reliable results showing high accuracy and convergence rate of the XCQ4 element.
本文采用由连续插值四边形元素增强的扩展有限元法研究了颗粒增强复合材料的断裂力学。这些复合材料具有不连续边界,如裂缝、空洞、孔洞和软夹杂物。在二维线性弹性变形问题中,采用扩展连续内插四边形元素(XCQ4)对这些边界进行建模。XCQ4 将传统扩展有限元方法中的富集函数与四节点四边形元素上的连续插值相结合。该元素使用节点值和平均节点梯度作为插值条件。在断裂分析中,应力强度因子(SIF)是必须定义的重要参数。 在本研究中,借助交互积分法评估了裂纹尖端的 SIF 值。所获得的数值结果与其他可靠结果进行了比较,显示 XCQ4 元素具有较高的精度和收敛速度。
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引用次数: 0
A study on mechanical properties of 1H-type crystalline nickel ditelluride 关于 1H 型结晶二碲化镍机械特性的研究
Pub Date : 2023-10-20 DOI: 10.15625/2525-2518/17619
Nguyen Danh, Truong, Nguyen Van Quynh
We used the molecular dynamic finite element method with Stillinger-Weber potential to study the mechanical behavior of monolayer 1H-type nickel ditelluride (1H-NiTe2) sheets under uniaxial tension. As the size of the pristine 1H-NiTe2 sheet increases, the Young’s modulus in the armchair direction increases by 6.2 %, while that in the zigzag one decreases by 6.0 %. Both tend to be size-independent in larger sheets and approach the same value at around 54 N/m. The ultimate stress in the armchair direction remains almost unchanged but that in the zigzag one reduces by about 9.5 % as the size inclines. Besides the influence of size, our results show that single vacancy defects strongly affect the ultimate stress and strain while having no effect on Young’s modulus and Poisson’s ratio. When a Te atom is missing at the sheet’s center, the ultimate stress in the armchair direction is reduced by 11.7 %, while a decrease of 16.0 % is caused by a Ni atom vacancy
我们利用分子动力学有限元法和 Stillinger-Weber 电位研究了单层 1H 型二碲化镍(1H-NiTe2)薄片在单轴拉伸下的力学行为。随着原始 1H-NiTe2 片材尺寸的增大,扶手方向的杨氏模量增加了 6.2%,而之字形方向的杨氏模量降低了 6.0%。在较大的薄片中,二者都趋向于与尺寸无关,并在 54 N/m 左右接近相同的值。扶手方向的极限应力几乎保持不变,但人字形方向的极限应力则随着尺寸的增大而减小约 9.5%。除了尺寸的影响外,我们的结果还表明,单个空位缺陷对极限应力和应变有很大影响,而对杨氏模量和泊松比没有影响。当薄片中心缺少一个 Te 原子时,扶手方向的极限应力降低了 11.7%,而一个 Ni 原子空位则导致极限应力降低了 16.0%。
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引用次数: 0
期刊
Vietnam Journal of Science and Technology
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