HNUE Journal of Science Hanoi National University of Education
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PHONON DYNAMICS AND OPTICAL PROPERTIES OF WURTZITE CdS
Get PDFThis study provides a comprehensive investigation of the structural, vibrational, optical, and thermodynamic properties of wurtzite cadmium sulfide (CdS) using computational methods. Using density functional theory (DFT) and phonon analysis, we reveal stable phonon dispersion with distinct acoustic and optical modes. The phonon density of states (PDOS) highlights the contributions of cadmium and sulfur sublattices, with key modes identified at 34.7 cm⁻¹, 124.4 cm⁻¹, 273 cm⁻¹, and 305.5 cm⁻¹. Optical analysis shows that CdS is transparent below 3.5 eV, exhibiting a maximum refractive index of 2.96 at 3.05 eV, and strong absorption at 7.76 eV (with an extinction coefficient of 1.88). Thermodynamic analysis indicates decreasing entropy and Gibbs free energy with rising temperature. The vibrational zero-point energy (ZPE) is calculated to be 0.124 eV, which is consistent across different calculation methods. These results provide valuable insights into the fundamental properties of CdS for its use in optoelectronic applications.This study provides a comprehensive investigation of the structural, vibrational, optical, and thermodynamic properties of wurtzite cadmium sulfide (CdS) using computational methods. Using density functional theory (DFT) and phonon analysis, we reveal stable phonon dispersion with distinct acoustic and optical modes. The phonon density of states (PDOS) highlights the contributions of cadmium and sulfur sublattices, with key modes identified at 34.7 cm⁻¹, 124.4 cm⁻¹, 273 cm⁻¹, and 305.5 cm⁻¹. Optical analysis shows that CdS is transparent below 3.5 eV, exhibiting a maximum refractive index of 2.96 at 3.05 eV, and strong absorption at 7.76 eV (with an extinction coefficient of 1.88). Thermodynamic analysis indicates decreasing entropy and Gibbs free energy with rising temperature. The vibrational zero-point energy (ZPE) is calculated to be 0.124 eV, which is consistent across different calculation methods. These results provide valuable insights into the fundamental properties of CdS for its use in optoelectronic applications
MAGNETIC FIELD AS A GROWTH ENHANCER: EVALUATING ITS POSITIVE IMPACTS ON AGRONOMIC CHARACTERISTICS OF MING ARALIA (Polyscias fruticosa)
Get PDFThis study investigated the effects of a magnetic field (MF) on agronomical and physiological characteristics of Ming aralia (Polyscias fruticosa) under hydroponic conditions. The evaluation focused on key root-related traits including root length, root hair density, fresh biomass, and dry biomass, as well as leaf-related traits such as leaf area, chlorophyll content, fresh and dry leaf biomass. Results revealed that MF exposure significantly enhanced root development, with treated plants showing a 21.5% increase in root length, a 48.2% improvement in root hair density, 24.8% and 36% higher fresh and dry root biomass, respectively, compared to the control group at day 50 of treatment. Similarly, leaf traits exhibited substantial improvements with MF treatment including a 20.2% increase in leaf area and a 20.4% enhancement in chlorophyll content by the end of the experiment. Fresh and dry leaf biomass of the treated group were also 25.2% and 28.1% higher, respectively, than those of the control group. These findings suggested that MF act as a biophysical stimulus, enhancing both morphological and physiological aspects of plant growth, likely by improving water and nutrient absorption, photosynthetic efficiency, and metabolic processes. The study highlights the potential of MF as a sustainable and effective tool to optimize plant development and productivity in controlled cultivation systems.This study investigated the effects of a magnetic field (MF) on agronomical and physiological characteristics of Ming aralia (Polyscias fruticosa) under hydroponic conditions. The evaluation focused on key root-related traits including root length, root hair density, fresh biomass, and dry biomass, as well as leaf-related traits such as leaf area, chlorophyll content, fresh and dry leaf biomass. Results revealed that MF exposure significantly enhanced root development, with treated plants showing a 21.5% increase in root length, a 48.2% improvement in root hair density, 24.8% and 36% higher fresh and dry root biomass, respectively, compared to the control group at day 50 of treatment. Similarly, leaf traits exhibited substantial improvements with MF treatment including a 20.2% increase in leaf area and a 20.4% enhancement in chlorophyll content by the end of the experiment. Fresh and dry leaf biomass of the treated group were also 25.2% and 28.1% higher, respectively, than those of the control group. These findings suggested that MF act as a biophysical stimulus, enhancing both morphological and physiological aspects of plant growth, likely by improving water and nutrient absorption, photosynthetic efficiency, and metabolic processes. The study highlights the potential of MF as a sustainable and effective tool to optimize plant development and productivity in controlled cultivation systems
CHARACTERISTICS OF THE LANDSCAPE CLASSIFICATION SYSTEM OF COMMUNES: CHO RA, BA BE, PHUC LOC, THUONG MINH AND DONG PHUC, THAI NGUYEN PROVINCE
Get PDFThe paper builds a landscape classification system to clarify the characteristics of landscape units in the communes of Cho Ra, Ba Be, Phuc Loc, Thuong Minh, and Dong Phuc, Thai Nguyen province. The diversity and spatial differentiation of the landscape of the area are shown through the model diagram of the landscape classification system; four landscape component maps and landscape (synthesis) maps of the five communes at the same scale of 1:50,000. The landscape units of the area are arranged into a system of seven levels, including one landscape system, one landscape subsystem, one landscape type, three landscape classes, five landscape subclasses, six landscape classes, and one hundred and nineteen types of landscape. The research results provide a database for studies on the use of landscapes for local purposes and a basis to help managers develop planning, orientation for use, and conservation of the landscape here in a reasonable and sustainable way.The paper builds a landscape classification system to clarify the characteristics of landscape units in the communes of Cho Ra, Ba Be, Phuc Loc, Thuong Minh, and Dong Phuc, Thai Nguyen province. The diversity and spatial differentiation of the landscape of the area are shown through the model diagram of the landscape classification system; four landscape component maps and landscape (synthesis) maps of the five communes at the same scale of 1:50,000. The landscape units of the area are arranged into a system of seven levels, including one landscape system, one landscape subsystem, one landscape type, three landscape classes, five landscape subclasses, six landscape classes, and one hundred and nineteen types of landscape. The research results provide a database for studies on the use of landscapes for local purposes and a basis to help managers develop planning, orientation for use, and conservation of the landscape here in a reasonable and sustainable way
DIVERSITY OF GROUND-ACTIVE SPIDER COMMUNITY ACROSS DIFFERENT TROPICAL FOREST HABITATS AND CLIMATE CONDITIONS IN NORTHERN VIETNAM
Get PDFA year-long survey of ground-active spiders was conducted in three typical tropical forest areas of Northern Vietnam, each characterized by distinct climatic conditions: Cuc Phuong National Park (CPNP, tropical monsoon climate of the Red River Delta), Tam Dao National Park (TDNP, high-elevation tropical monsoon climate), and Cat Ba National Park (CBNP, maritime climate). Four types of habitats were selected in each region: natural forest and disturbed forest (both with multi-layered vegetation structures), and shrubland and acacia plantation (both with simple-layer vegetation structures). Spiders were sampled using pitfall traps. Cursorial hunters and ground-level web builders were the dominant guilds in all study areas. Spider diversity was compared across the study areas. Cluster analysis showed that the species composition in the maritime climate area (CBNP) was significantly different from that in the other areas. Spider diversity was also compared between habitats with multi-layer vegetation structures (multi-LVS) and those with simple-layer vegetation structures (simple-LVS). Both species composition and spider abundance were higher in habitats with multi-LVS than those with simple-LVS. The results of this study highlight the importance of preserving natural ecological processes to conserve biodiversity in multi-VLS habitats and to aid in the restoration of biodiversity in simple-LVS habitats.Keywords: ground-active spiders, regional climate, Northern Vietnam.A year-long survey of ground-active spiders was conducted in three typical tropical forest areas of Northern Vietnam, each characterized by distinct climatic conditions: Cuc Phuong National Park (CPNP, tropical monsoon climate of the Red River Delta), Tam Dao National Park (TDNP, high-elevation tropical monsoon climate), and Cat Ba National Park (CBNP, maritime climate). Four types of habitats were selected in each region: natural forest and disturbed forest (both with multi-layered vegetation structures), and shrubland and acacia plantation (both with simple-layer vegetation structures). Spiders were sampled using pitfall traps. Cursorial hunters and ground-level web builders were the dominant guilds in all study areas. Spider diversity was compared across the study areas. Cluster analysis showed that the species composition in the maritime climate area (CBNP) was significantly different from that in the other areas. Spider diversity was also compared between habitats with multi-layer vegetation structures (multi-LVS) and those with simple-layer vegetation structures (simple-LVS). Both species composition and spider abundance were higher in habitats with multi-LVS than those with simple-LVS. The results of this study highlight the importance of preserving natural ecological processes to conserve biodiversity in multi-VLS habitats and to aid in the restoration of biodiversity in simple-LVS habitats.Keywords: ground-active spiders, regional climate, Northern Vietnam
ASSESSMENT OF DROUGHT IN THE SOUTHERN SUB-REGION OF THE RED RIVER DELTA FOR AGRICULTURAL DEVELOPMENT
Get PDFThe southern sub-region of the Red River Delta possesses favorable natural conditions for agricultural development and plays an important role in the country’s agricultural output. Nevertheless, this region is highly vulnerable to natural disasters, particularly droughts, which pose significant challenges to agricultural productivity. This study applies a combination of statistical and spatial analysis methods to examine drought characteristics in the Southern Subregion of the Red River Delta. The research methodology included: (i) calculation of the K drought index, (ii) estimation of drought and extreme drought frequency, (iii) application of simple linear regression analysis, and (iv) interpolation using the Inverse Distance Weighting (IDW) method. Monthly precipitation and evapotranspiration data from 1991 to 2020 were utilized. The results show that droughts occurred in almost all months, except August and September, with the most severe events concentrated in December, January, and February. Although the region is relatively homogeneous, spatial variations are apparent. Ha Nam Province consistently recorded the lowest drought severity across all indicators, including drought frequency, extreme drought frequency, and the annual drought index. In contrast, a prominent elongated zone (or “trough”) with a high frequency of severe drought months is evident in the spatial distribution maps. Additionally, a drought tongue with increasing severity extends from Ha Nam in a northeast–southwest direction toward Van Ly (Nam Dinh). These findings provide critical insights for disaster risk reduction and serve as a scientific basis for agricultural planning and sustainable development in the region.The southern sub-region of the Red River Delta possesses favorable natural conditions for agricultural development and plays an important role in the country’s agricultural output. Nevertheless, this region is highly vulnerable to natural disasters, particularly droughts, which pose significant challenges to agricultural productivity. This study applies a combination of statistical and spatial analysis methods to examine drought characteristics in the Southern Subregion of the Red River Delta. The research methodology included: (i) calculation of the K drought index, (ii) estimation of drought and extreme drought frequency, (iii) application of simple linear regression analysis, and (iv) interpolation using the Inverse Distance Weighting (IDW) method. Monthly precipitation and evapotranspiration data from 1991 to 2020 were utilized. The results show that droughts occurred in almost all months, except August and September, with the most severe events concentrated in December, January, and February. Although the region is relatively homogeneous, spatial variations are apparent. Ha Nam Province consistently recorded the lowest drought severity across all indicators, including drought frequency, extreme drought frequency, and the annual drought index. In contrast, a prominent elongated zone (or “trough”) with a high frequency of severe drought months is evident in the spatial distribution maps. Additionally, a drought tongue with increasing severity extends from Ha Nam in a northeast–southwest direction toward Van Ly (Nam Dinh). These findings provide critical insights for disaster risk reduction and serve as a scientific basis for agricultural planning and sustainable development in the region
EFFECTS OF ALCOHOL-SOLUBLE COMPONENTS IN SOYMILK RESIDUE ON PLASMA LIPID LEVELS, LIPID DIGESTIONAND BODY WEIGHT GAIN IN SWISS MICE
Get PDFThe present study was conducted to examine the effects of alcohol-soluble components (alcohol extract, AE) in soymilk residue (SR) on body weight gain, plasma lipid levels, and lipid digestion in Swiss mice. Aqueous ethanol was used to extract the SR, afterwhich the residue and the supernatant were separated. The supernatant was then dried to produce the AE. Four experimental diets were formulated and designated as CD (control diet), CD+AE20 (CD supplemented with 20 g AE/kg), CD+AE40 (CD supplemented with 40 g AE/kg), and CD+AE60 (CD supplemented with 60 g AE/kg). Six mice (with an initial body weight of 24 g) were distributed into each of eight cages, with two replicate cages per dietary treatment. The experimental mice were fed with the test diets ad libitum for 4 weeks. The results showed that the final body weights of mice fed with AE-supplemented diets were lower than those fed with the control diet, while no differences in feed intake were found among the treatments. Moreover, the AE significantly reduced body weight gain with significant differences observed in mice receiving AE supplementation levels of 40 and 60 g/kg. The mice fed with AE-supplemented diets exhibited lower plasma concentrations of total cholesterol, low-density lipoprotein, and triglyceride as well as lower intestinal total bile acid level and lipase activity, but higher lipid content in feces, compared with those fed with the control diet. These findings indicated that the AE in SR negatively affected the lipid digestion process, therefore reducing plasma cholesterol levels and body weight gain in Swiss mice.The present study was conducted to examine the effects of alcohol-soluble components (alcohol extract, AE) in soymilk residue (SR) on body weight gain, plasma lipid levels, and lipid digestion in Swiss mice. Aqueous ethanol was used to extract the SR, afterwhich the residue and the supernatant were separated. The supernatant was then dried to produce the AE. Four experimental diets were formulated and designated as CD (control diet), CD+AE20 (CD supplemented with 20 g AE/kg), CD+AE40 (CD supplemented with 40 g AE/kg), and CD+AE60 (CD supplemented with 60 g AE/kg). Six mice (with an initial body weight of 24 g) were distributed into each of eight cages, with two replicate cages per dietary treatment. The experimental mice were fed with the test diets ad libitum for 4 weeks. The results showed that the final body weights of mice fed with AE-supplemented diets were lower than those fed with the control diet, while no differences in feed intake were found among the treatments. Moreover, the AE significantly reduced body weight gain with significant differences observed in mice receiving AE supplementation levels of 40 and 60 g/kg. The mice fed with AE-supplemented diets exhibited lower plasma concentrations of total cholesterol, low-density lipoprotein, and triglyceride as well as lower intestinal total bile acid level and lipase activity, but higher lipid content in feces, compared with those fed with the control diet. These findings indicated that the AE in SR negatively affected the lipid digestion process, therefore reducing plasma cholesterol levels and body weight gain in Swiss mice
CONTEMPORARY LEGEND STUDIES: TRENDS, RESOURCES, AND PROSPECTS
Get PDFVới khả năng lấp đầy những khoảng trống trong kiến thức thực nghiệm của con người bằng những giả thuyết về cách thức “vận hành siêu hình” của thế giới, truyền thuyết đương đại trở thành nguồn tài nguyên tuyệt vời cho các học giả quan tâm đến phương thức trong đó truyền thống cổ xưa, văn hóa bản địa và xã hội đương đại mới tương tác và định nghĩa lẫn nhau trong thế giới thực và trên các phương tiện truyền thông. Nghiên cứu này, với mục tiêu đánh giá tổng quan và bước đầu giới thiệu những khái niệm, tranh luận nền tảng về một tiểu loại tự sự dân gian còn khá mới mẻ ở Việt Nam, sẽ tập trung vào tổng thuật ngắn về các khuynh hướng nghiên cứu cơ bản, xác lập vai trò và vị trí của tiểu loại này trong hệ thống thể loại tự sự dân gian. Bài viết cũng hướng đến việc nhấn mạnh trữ lượng và trình bày các viễn cảnh, chủ đề nghiên cứu tiềm năng liên quan đến tiểu loại đang có động lực phát triển bậc nhất trên thế giới hiện nay.With the ability to fill gaps in human empirical knowledge with hypotheses about the \u27metaphysical workings\u27 of the world, contemporary legends have become a valuable resource for scholars interested in how ancient traditions, indigenous cultures, and contemporary societies interact and define each other in the real world and through media. This study aims to provide an overview and an introduction to foundational concepts and debates surrounding a relatively new subgenre of folklore in Vietnam, focuses on a summary of the primary research trends, and establishes the role and position of this subgenre within the system of folk narrative genres. The study also emphasizes the available resources, potential research prospects, and themes related to this rapidly developing subgenre worldwide
FURTHER DISCUSSION ON “COMPARATIVE LITERATURE” AND THE FORMATION AND DEVELOPMENT OF CHINESE COMPARATIVE LITERATURE
Get PDFNgày nay, làn sóng toàn cầu hoá đã lan đến tận hầu khắp các địa hạt, văn học các nước không thể giam mình trong lâu đài dân tộc trung tâm luận biệt lập, các quốc gia với nền văn học của mình đều tham dự vào nền văn chương thế giới. Các trào lưu văn học, tác gia và tác phẩm thông qua sự mở rộng của thị trường văn hóa (xuất bản và dịch thuật) tiếp xúc với nhau, tác động đa chiều tới nhau. Và bản thân văn học cũng không còn có thể yên nhiên trong địa vực của mình, mà chịu ảnh hưởng của các loại hình nghệ thuật khác, chịu tác động của cả các yếu tố phi văn học. Tình hình đó hoặc làm sâu sắc thêm những mối quan hệ nội tại của mỗi nền văn học, cũng như làm hình thành thêm những mối quan hệ mới giữa văn học với các thành tố văn hóa khác. Những mối quan hệ ấy sẽ được lí giải và nghiên cứu bởi văn học so sánh. Các nước châu Á như Trung Quốc và Nhật Bản, do tính cách tiêu biểu của văn hóa tại châu lục và đều là những “đầu cầu” của mối liên hệ giao lưu Đông - Tây nên rất đáng được xét đến như những trường hợp quan trọng trong lịch sử văn học thế giới nói chung, lịch sử văn học so sánh nói riêng. Bài viết của chúng tôi thêm một lần khẳng định vai trò quan trọng của bộ môn văn học so sánh và tập trung nghiên cứu sự hình thành, phát triển ngành nghiên cứu văn học này tại Trung Quốc.Nowadays, the wave of globalization has influenced every field, encouraging the extension of the domestic literature which was previously confined within their philosophy to the global literature. Through the interdimensional exchange of cultural products via publication and translation, several trends of writing, authors, and literary works were widespread. This circumstance also brings various non-literary effects of other art forms into the literature, which deepens the internal relationships of literary dynamics in their own country while forming new relationships between the literature and other cultural elements. These relationships might be well analyzed and researched by Comparative literature (Littérature comparée). East Asian countries such as China and Japan, whose cultures are representatives of the continent’s culture and are ”bridgeheads” of the East-West interaction, can be considered note-worthy cases in the history of World Literature, particularly in the history of Comparative Literature. This essay affirms the significance of Comparative Literature and focuses on tracing the formation and development of this literary research field in China
THE ANTITHESIS OF TRADITION IN YI MUN-YOL\u27S GARUDA FROM THE PERSPECTIVE OF NARRATIVE DISCOURSE
Get PDFBài viết này đi sâu nghiên cứu phản đề truyền thống trong truyện ngắn Kim sí điểu (Garuda) của Yi Mun-yol (이문열) thông qua phương pháp phân tích diễn ngôn trần thuật. Bài viết khám phá các chiến lược diễn ngôn mà Yi Mun-yol sử dụng để tạo lập phản đề truyền thống, bao gồm hình tượng nhân vật, tái diễn giải và chuyển đổi ngữ cảnh. Thông qua mâu thuẫn trong hệ thống nhân vật, tác giả thể hiện sự đấu tranh giữa cái mới và cái cũ. Chiến lược tái diễn giải mang lại cách hiểu khác về diễn ngôn truyền thống. Trong khi đó, việc chuyển đổi ngữ cảnh tạo ra sự giao thoa giữa quá khứ với hiện tại. Các chiến lược diễn ngôn mang đến không gian văn học độc đáo, thúc đẩy tiến trình sáng tạo. Nghiên cứu nhấn mạnh rằng sáng tác của Yi Mun-yol góp phần tái cơ cấu giá trị truyền thống, làm phong phú cảnh quan văn học Hàn Quốc đương thời.This article delves into the traditional antithesis in Yi Mun-yol\u27s (이문열) short story Garuda through narrative discourse analysis. It explores the discursive strategies Yi Mun-yol employs to establish traditional antithesis, including poetics of character, reinterpretation, and contextual shift. The author portrays the struggle between the new and the old through the conflicts within the character system. The strategy of reinterpretation provides a different understanding of traditional discourse. Meanwhile, contextual shift creates an intersection between the past and the present. These discourse strategies offer a unique literary space, promoting creativity. The study emphasizes that Yi Mun-yol\u27s works contribute to the restructuring of traditional values, enriching the contemporary Korean literary landscape
TRANSFORMATIONS IN MO MUONG PERFORMANCE ART IN THE DIGITAL AGE
Get PDFNghiên cứu này tìm hiểu sự biến đổi của nghệ thuật biểu diễn Mo Mường trong thời đại kĩ thuật số. Theo truyền thống, Mo Mường do Ôông Mo biểu diễn gắn liền với các nghi lễ, phong tục tập quán dân gian của cộng đồng người Mường, diễn ra trong môi trường vật chất và văn hóa như nhà sàn và các buổi họp mặt cộng đồng. Tuy nhiên, trong giai đoạn hiện đại, thực tiễn thực hành diễn xướng Mo Mường này đã mở rộng sang lĩnh vực kĩ thuật số, tích hợp với không gian mạng để hình thành nên cái được gọi là Văn hóa dân gian kĩ thuật số (E-folklore). Thông qua nghiên cứu thực địa dân tộc học, phân tích dữ liệu ngữ văn dân gian và phỏng vấn sâu các nghệ nhân, nghiên cứu này xem xét thời đại kĩ thuật số đã thay đổi việc thực hành, bảo tồn và phổ biến Mo Mường như thế nào. Nghiên cứu cũng hướng đến việc nhấn mạnh sự chuyển đổi từ truyền miệng truyền thống sang ghi âm kĩ thuật số và tương tác trực tuyến giữa nghệ nhân và khán thính giả, đánh giá tác động đối với di sản văn hóa và bản sắc cộng đồng.This study explores the transformations in the performance art of Mo Muong in the digital age. Traditionally, Mo Muong is performed by Oong Mo and is closely associated with the rituals and folk customs of the Muong community. These performances typically occur within the physical and cultural environments, such as stilt houses and community gatherings. However, in modern times, the practice of Mo Muong has expanded into the digital realm, integrating with cyberspace to form what is known as Digital Folklore (E-folklore). Through ethnographic fieldwork, analysis of folk literature data, and in-depth interviews with storytellers, this research examines how the digital age has altered the practice, preservation, and dissemination of Mo Muong. The study also highlights the transition from traditional oral transmission to digital recording and online interaction between artisans and audiences, evaluating the impact on cultural heritage and community identity