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In Vietnam, many legal documents have been issued to set out requirements for general education innovation, emphasizing innovation in testing and evaluating educational outcomes. However, theoretical issues related to the design of measurement tools, especially standardized tools, have not been fully and systematically studied for implementation in practice. In addition, although innovation in teaching methods and assessment is focused on, teachers still face many difficulties in designing and using assessment tools. The purpose of this paper is, through systematizing research and implementation practices, to provide some theoretical and practical issues on assessment according to the 2018 General Education Program, from which some test problems and ways to solve them are proposed.

This paper focuses on studying the influence of temperature on the working process of Panasonic NCR-18650B electric vehicle battery. Through the Matlab - Simulink simulation tool, the effects related to the charging/discharging process of electric vehicle batteries such as voltage, current and state of charge (SOC) have been considered at different temperature of 0, 25, 50 degrees Celsius. Research results contribute to optimizing battery usage, thereby minimizing the impact of batteries on the environment, contributing to the development of the current electric car industry.

This study aims to identify suitable density of suspended trays and care regime, which was conducted from February to November 2022 at Tay Van Boi, Lan Ha Bay, Cat Ba, Cat Hai - Hai Phong to improve growth, survival rates and helping to shorten the time for snout otter clam grow-out culture. The experiment was carried out with 3 treatments: Densities of 4, 8 and 12 trays/4 m2 combined with 3 care regimes during grow-out culture. The results showed that densities of 4 and 8 trays/4 m2 were higher growth than the remaining treatment, specifically length was from 32.9 - 36.8 mm and survival rate was over 84%, with a significant difference, compared to a density of 12 trays/4 m2 with 3 different care regimes. The results show that to increase productivity and reduce production costs and care time, a density of 8 trays/4 m2 with 3 care regimes/a culturing period should be chosen. The study has also propounded disease prevention and treatment measures for the Snout otter clam to help control the disease well and proposed solutions on farming techniques that contribute to high and sustainable economic efficiency.

In the context of economic integration and climate change, the companies need to conduct corporate social responsibility practices to meet the sustainable development. This study attempts to assess the extent of corporate social responsibility disclosure (CSRD) in case of 601 listed Vietnamese enterprises. Data is gathered from Vietnamese listed annual reports, financial statements, and other sources. The amount of voluntary and mandatory CSRD is measured by Global Reporting Initiatives (GRI) recommendations and Vietnamese regulations, respectively. The findings indicate that the general level of CSRD in Vietnam is low, no mandatory CSR items are revealed by all enterprises, and the amount of CSRD varies by industry sector. To enhance the CSRD of Vietnamese listed firms, local government is suggested to strengthen propaganda for enterprises on the obligations and benefits of implementing CSR.

The research was conducted to complete technological protocol of biomass production of algae Nannochloropsis oculata with both culture methods in plastic bags and photo-bioreactor systems. The results show that in the nylon bag system, algae reached a peak of biomass density at day-8 of culture with 80 million cells per ml. In the photo-bioreactor systems, algae were higher density (180 million cells per ml), and longer period of culture (15 days of culture) than in plastic bags. The total products of 404.4 kg of fresh concetrated algae and 57.6 kg of dried algae powder which were suitable produced under climate conditions in Nghe An. All the algae products met the quality and requirements for use as food for aquatic animals as well as raw materials for the production of functional foods for humans.

Camellia piquetiana, one of the endemic species of Vietnam, is classified as Critically Endangered (CR) by the IUCN. A reassessment of its conservation status and research into propagation methods are essential for its conservation. Our survey recorded 246 mature individuals in the wild at three locations in Lam Dong Province: Bao Loc City, Bao Lam District, and Da Huoai District. The conservation assessment for this species, determined with GeoCat software, is still CR. Propagation by partially uncoated seeds had a higher propagation efficiency than by coated seeds. The germination percentage was 92.22%; the seeds began germination after 11 days and finished after 29.33 days. The results showed that stem cuttings immersed in a concentration of 500 ppm indole-3-butyric acid for 10 minutes with a 100% coir substrate gave the highest survival percentage (90.00%), rooting percentage (86.67%), average number of roots (4.54), root length (4.86 cm), and rooting index (21.98) after 90 days.

This paper aimed to present a mini review on applying Structural Equation Modeling (SEM) for behavioural research on solid waste management. This paper examined the literature on behavioural research of solid waste management across various geographical regions. Households were the ubiquitous research subject of the studies on waste separation behaviour, while business sectors - accounting for a large amount of waste generation - were not pervasively studied. Theory of planned behaviour (TPB) was the dominant theory model for studies on waste separation behaviour. However, waste separation behaviour would be extremely complex so base theory integration was highly recommended. Five-point and seven-point Likert scales were the most ubiquitous scales utilised. PLS-SEM would be a “Silver bullet” due to its advantages in data analysis. The results of this study are expected to be a reference for managers, decision-makers, policymakers, researchers, and other stakeholders in solid waste management studies and projects.

Mosquitoes are vectors of serious human diseases, i.e., dengue fever, malaria, and yellow fever. The number of dengue fever cases has seen 30 times increase in the previous 50 years. The research and development of mosquito repellents as personal care products is an approach for preventing diseases spread by mosquitoes, besides others for killing larvae. Most commercial mosquito repellents today are derived from chemical synthesis associated with many risks of adverse effects on human health, particularly for the nervous system. Natural products are appraised to be a tremendous means of overcoming these restrictions and shortcomings. The ability of essential oils extracted from herbs to repel mosquitoes has drawn much more attention recently. In this review, we have summarized the chemical composition, the mosquito repellent capacity, and the application of essential oils.

The hierarchical nanostructures (3D) with their large specific surface area and abundant pores usually possess unique physical and chemical properties for various important applications. In this report, we have introduced simple and scalable routes to successfully synthesize 3D iron oxide nanostructures, including porous cubes and bird nest-like architecture. The 3D sponge-like Fe2O3 nanocubes were formed by an annealing process of perfect Prussian Blue (PB) microcubes, which were built from small nanoparticles linked together. Whereas, the 3D bird nest-like Fe2O3 nanostructures were formed by the transformation of C@FeOOH nanoflower precursors, which were constructed by primary nanorods. The results indicated that the obtained materials show monodispersity, uniform morphology, ultra-porosity and extremely high specific surface area. With unique characteristics, the 3D Fe2O3 nanostructures could be potential candidates for various important fields such as catalysts, absorption and gas sensors.

We investigate the assembly of a binary mixture of patchy colloids and droplets into crystal structures by use of the space-filling principle and Metropolis Monte Carlo simulations. Here, colloids with six patches in an octahedral symmetry attract droplets, whereas the colloid-colloid and droplet-droplet pairwise interactions are purely hard-core repulsions. Within parameter space regions that allow for stable binary crystals, we find the formation of different structure types, which are colloidal analogs of the NaCl phase and pyrite (FeS2) phase, as a function of the droplet-to-colloid sphere diameter ratio. This finding is consistent with theoretical predictions. Notably, while the NaCl structure type is a commonly known structure of hard-sphere colloids and nanoparticles, the formation of the FeS2 structure type from colloidal dispersion has not been explored. Our approach suggests a potential route to obtain colloidal crystals with more complex structures.

Trong bài báo này, các tính chất điện tử và truyền dẫn của vật liệu hai chiều đơn lớp Janus TiSiSeP2 được nghiên cứu bằng pháp lý thuyết phiếm hàm mật độ (DFT). Các tính toán cho thấy đơn lớn TiSiSeP2 có cấu trúc bền vững và có khả năng tổng hợp được bằng thực nghiệm. Ở trạng thái cơ bản, đơn lớp Janus TiSiSeP2 là bán dẫn với vùng cấm xiên có bề rộng là 1,23 eV khi được tính bằng phiếm hàm lai HSE06. Các đặc trưng điện tử của TiSiSeP2 phụ thuộc rất lớn vào biến dạng, đặc biệt là độ rộng vùng cấm. Bên cạnh đó, các đặc trưng truyền dẫn của TiSiSeP2 cũng đã được tính toán một cách hệ thống trong bài báo này. Các kết quả nghiên cứu góp phần hiểu rõ hơn về các tính chất vật lý của vật liệu hai chiều đơn lớp Janus TiSiSeP2.

From 1973 to 1980, responding to the appeals for assistance from the Government of the Democratic Republic of Vietnam, the Germany Democratic Republic has provided aid and assistance for the reconstruction process and contributed to the fundamental changes in the appearance of Vinh city. From a historical point of view, the article reconstructs the assistance and construction process, and simultaneously evaluates the impact and characteristics of the assistance from the Germany Democratic Republic on the reconstruction of Vinh city in the period 1973 - 1980.

This paper presents a simple thermal-electrical model of a photovoltaic panel with a cooler-integrated sun tracker. Based on the model and obtained weather data, we analyzed the improved overall efficiency in a year as well as the performance in each typical weather case for photovoltaic panels with fixed-tilt systems with a tilt angle equal to latitude, fixed-tilt systems with cooler, a single-axis sun tracker, and a cooler-integrated single-axis sun tracker. The results show that on a sunny summer day with few clouds, the performance of the photovoltaic panels with the proposed system improved and reached 32.76% compared with the fixed-tilt systems. On a sunny day with clouds in the wet, rainy season, because of the low air temperature and the high wind speed, the photovoltaic panel temperature was lower than the cooler’s initial set temperature; the performance of the photovoltaic panel with the proposed system improved by 12.55% compared with the fixed-tilt system. Simulation results show that, over one year, the overall efficiency of the proposed system markedly improved by 16.35, 13.03, and 3.68% compared with the photovoltaic panel with the fixed-tilt system, the cooler, and the single-axis sun tracker, respectively. The simulation results can serve as a premise for future experimental models.

This paper investigates the effect of cash in advance (CIA) on the export decision in Vietnamese firms in the face of financial and institutional constraints. We find that the CIA has a positive relationship with the probability of export in the institutionally constrained firms, and this effect becomes pronounced when those firms are small and medium-sized or also suffer financial constraints. This finding suggests that the CIA does help firms export by mitigating the joint effects of constraints imposed on Vietnamese small and medium-sized enterprises (SMEs).

Recently, permeable concrete has been considered one of the "Best Management Practices" in rainwater collection and cleaning. The outstanding properties of this type of concrete are its relatively high porosity (typically 15 ÷ 30% in volume) and the linking/connection of the internal pore system resulting in high water permeability and retention. However, one of the limitations to the widespread application of this eco-friendly material is the decrease of permeable capacity over time due to the clogging materials and the lack of regular maintenance. This paper performs an experimental approach for manufacturing permeable concrete that has both high water permeability and meets the strength requirement (1). At the same time, the influence of clogging sand and typical maintenance methods on the infiltration rate of permeable or pervious concrete is presented (2). Based on the literature review and obtained experimental results in this study, maintenance measures to ensure the required permeability for urban surface structures and sustainable surface water drainage are also proposed (3).

The Central Highlands (Tây Nguyên) is a center of yellow camellia diversity in Vietnam and the world. The Central Highlands contains 18 of Vietnam’s yellow camellia species, accounting for 37% of yellow camellia species in Vietnam and 28% of yellow camellia species worldwide. Moreover, all 18 yellow camellia species in the Central Highlands are endemic to Vietnam. The camellias of the Central Highlands belong to nine sections, accounting for 75% of the world. The yellow colors occur in three groups: pale yellow, yellow, and yellow with compound colors. The yellow camellia distribution is dispersed at 500–1600 m elevation in evergreen broadleaf forests and mixed wood-bamboo forests.

Camellia sphamii is described and illustrated as a new species of section Piquetia from Hamasin village, D’ran town, Don Duong district, Lam Dong province, Vietnam. C. sphamii is similar to C. proensis (Quach, Luong et al., 2021) but differs from it in several morphological features: mature leaves cordate at base, young leaves purple; pericarp 7–8 mm thick with dense hair on the outer surface, flower buds ovate, ferruginous; sepals 5, hemisphere, concave, finely hairy on the outer surface, sparsely hairy on the inside, petals 7, finely hairy on the outer surface, with translucent margin, concave; style 5, ½ basally united; capsule 5 locular. Information on its phenology, distribution, ecology, and conservation status is also provided.

Motivated by the successful exfoliation of a novel two-dimensional MoSi2N4 materials, in this work, we investigate the structural and electronic properties of a novel single-layer MoSi2N4 and the effect of strain engineering by using the first-principles calculations based on the density functional theory. The single-layer MoSi2N4 has a hexagonal structure with a space group of P6m1, which is dynamically stable. The material exhibits a semiconducting characteristic with an indirect band gap of 1.80/2.36 eV calculated by using the PBE/HSE functional. The conduction band minimum at the K point of the material originates from the Mo atom, while its valence band maximum at the G point is contributed by the hybridization between the Mo and N atoms. The electronic properties of the single-layer MoSi2N4 can be modulated with strain engineering, giving rise to a transition from a semiconductor to a metal and tending to a change in the band gap. Our results demonstrate that the single-layer MoSi2N4 is a promising candidate for electronic and optoelectronic applications.

Dangshen Codonopsis javanica exhibits invaluable medicinal properties in herbal remedies; however, there has currently not been much specific analysis of the phytochemicals and bioactivities of this plant. The root ethanol extract of C. javanica contains substances such as saponins, phenolic acids, terpenoids, and alkaloids. It displays an antibacterial effect against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus cereus with the IC50 values of 150, 100, 150, and 90 μg/mL, respectively. The antioxidant capacity of the root extract was also observed with an IC50 value of 46.8 ± 6.8 μg/mL. Furthermore, the extract exhibits activity on human cancer cell lines HepG2 (IC50 = 83.6 ± 2.7 μg/mL) and MCF-7 (IC50 = 95.3 ± 2.3 μg/mL). Hence, this study provides the basic data for further research on the bioactivities of natural compounds of Dangshen C. javanica for the first time.

The Monte Carlo N-Particle code (MCNP4C2 version) has been modified for atomic relaxation in both source code and library to simulate XRF spectra for different measurement configurations. The modified code was then used to simulate XRF spectra of six metal samples: Ni, Cu, Zn, Pd, Ag, Au, and Au alloys on an XRF spectrometer. The results are compared to those of experimental measurements. The intensity ratios of line pairs Kb1/Ka1 and Lb1/La1 between simulated and experimental values differ by about 4%-11% for the six single metals. The relative intensities of the Au alloys, compared to AuLa1, were in the range of 0.02%-26.00%. The modified MCNP4C2 code is capable of forecasting the basic characteristics of new XRF designs.

Trong công trình này, màng tổ hợp của vật liệu graphene (Gr) – ống nano cácbon hai tường (DWCNT) và hạt nano kim loại vàng (AuNPs) (DWCNT-AuNPs-Gr) đã được chế tạo bằng phương pháp lắng đọng pha hơi nhiệt hóa học (CVD). Hình thái học bề mặt và các tính chất điện, điện hóa của vật liệu tổ hợp đã được khảo sát thông qua kính hiển vi điện tử quét phát xạ trường, phổ Raman, điện trở bốn mũi dò và kỹ thuật quét thế vòng (CV). Với nồng độ DWCNTs 0,3 g/L và tốc độ quay phủ 4000 vòng/phút, vật liệu DWCNTs-AuNPs-Gr có điện trở bề mặt giảm 2,3 lần so với màng Gr và đạt khoảng 549 W/sq; dòng đỉnh đáp ứng trong dung dịch 2 mM K3[Fe(CN)6]/K4[Fe(CN)6] trong 0,1 M PBS đạt 15,79 µA tại 50 mV/s, cao gấp 1,48 lần so với điện cực biến tính màng Gr và gấp 2,57 lần so với điện cực trần. Vật liệu DWCNTs-AuNPs-Gr có tiềm năng ứng dụng trong cảm biến điện hóa để phát hiện các phần tử sinh học khác nhau.

This paper presents the change in the volt-farad characteristics of the Al/SiO2/n-Si structure irradiated with helium ions with the energy of 5 MeV in the frequencies of 1, 10, 100, and 1000 kHz. The voltage dependence of the capacitance and the frequency dependence of the dissolution angle are measured on an LCR Agilent E4980A and Agilent 4285A meter. The hodograph of the irradiated structure shows that there is a formation of a quasi-continuous radiation-disturbed layer at a fluence of 1012 cm–2 with U < –7 V and 1013 cm–2 with U < –20 V, which enhances the speed of charged particles, thereby increasing the reverse current in the irradiated structure.

Trong nghiên cứu này, vật liệu nano Gd(OH)3 dạng thanh đã được tổng hợp bằng phương pháp polyol với tiền chất là gadolini clorua hydrat (GdCl3·xH2O), natri hydroxit và chất hoạt động bề mặt là trietylen glycol (C6H14O4). Sản phẩm đã được đặc trưng bằng các kỹ thuật XRD, SEM, TEM, TG-DTA, EDX. Kết quả cho thấy vật liệu Gd(OH)­3 thu được có cấu trúc dạng thanh nano, đồng đều với khích thước 20 × 200 nm và tinh khiết. Vật liệu được ứng dụng trong phản ứng oxy hóa nâng cao đối với quang hóa phân hủy Congo đỏ của hệ xúc tác UV/Gd(OH)3 và UV/H2O2/Gd(OH)3.

Nghiên cứu này đã ứng dụng thang đo của Parasuraman để đo lường mức độ hài lòng của người nộp thuế về chất lượng dịch vụ tuyên truyền hỗ trợ tại Cục Thuế tỉnh Kiên Giang. Trên cơ sở lý thuyết về chất lượng dịch vụ công cộng, kế thừa phương pháp đánh giá chất lượng dịch vụ của Parasuraman gồm 7 thành phần: Cơ sở vật chất; Tính minh bạch; Năng lực phục vụ; Đáp ứng; Tin cậy; Sự công bằng, dân chủ; Sự cảm thông. Từ mô hình đề xuất ban đầu, tác giả tiến hành khảo sát trên 350 mẫu nghiên cứu và áp dụng phương pháp kiểm định Cronbach Alpha và phân tích EFA, ANOVA. Kết quả nghiên cứu cho thấy mức độ hài lòng của người nộp thuế đối với chất lượng dịch vụ tuyên truyền hỗ trợ tại Cục Thuế tỉnh Kiên Giang gồm 7 thành phần: 1. Cảm thông, công bằng; 2. Tin cậy; 3. Đáp ứng; 4. Công khai quy trình; 5. Năng lực phục vụ; 6. Cơ sở vật chất; 7. Công khai công vụ. Từ kết quả nghiên cứu, bài viết đưa ra các giải pháp nhằm cải thiện và nâng cao chất lượng dịch vụ tuyên truyền hỗ trợ cho người nộp thuế.

Bài báo này thể hiện kết quả sàng lọc hoạt tính chống oxy hóa của 5 loài rong nâu S. angustifolium, S. aemulum, S. assimile, S. feldmanii và S. ilicifolium ở tỉnh Khánh Hòa. Hoạt tính chống oxy hóa được đánh giá dựa trên các hoạt tính chống oxy hóa tổng, khử Fe và DPPH. Đồng thời cũng chỉ ra hàm lượng phlorotannin/ polyphenol tương ứng ở trong các loài rong này. Những loài này được thu mẫu vào thời gian thành thục sinh sản của chúng. Kết quả cho thấy hàm lượng phlorotannin/ polyphenol ở rong S. angustifolium là cao nhất. ở 5 loài nghiên cứu, hoạt tính khử Fe thể hiện mạnh hơn các hoạt tính khác, hoạt tính khử Fe của S. angustifolium là cao nhất. Hoạt tính bắt gốc tự do DPPH dao động trong khoảng 50% - 96%.

Many people believe that, with the signing of the Indo-Soviet Treaty of Peace Friendship and Cooperation in 1971, India now gave up her non-aligned guideline. Reexamining the non-aligned policies of India regarding her relationship with Soviet after 1971, with a focus on the mutual international issues, this article concludes that, in both theory and reality, India did not violate the non-aligned principle. Yet her attitude and actions toward Soviet was neither "positive" nor "active" compared toward the United States. [ABSTRACT FROM AUTHOR]