САДЫ И АРХИТЕКТУРА ИМПЕРАТОРСКИХ ПОГРЕБАЛЬНЫХ КОМПЛЕКСОВ ВЬЕТНАМА, КАК РЕЗУЛЬТАТ ВЛИЯНИЯ КИТАЙСКОЙ КУЛЬТУРЫ НА СТРАНЫ ЮГО-ВОСТОЧНОЙ АЗИИ

The article is devoted to the issues of borrowing and identity of the Vietnamese garden culture on the example of the burial complexes of China and Vietnam. In all countries of Southeast Asia and Indochina, where the traditions of Chinese gardening were perceived, the gardens of the imperial funerary complexes demonstrated the degree of popularity of the deceased emperor, the economic condition of the empire, modeled the emperor's “life” in the afterlife with maximum use of Feng Shui planning principles. All planning aspects prescribed by this doctrine were observed in Vietnamese burial complexes, but with a certain adjustment in accordance with their own aesthetic views, functional preferences and perceptions of expediency. The field surveys carried out by the authors of the burial complexes of Vietnam and China in the cities of Hue, Shenyang and the outskirts of Beijing served as sources for the study. Globalization trends in the field of horticultural culture from the period of the Chinese conquests of Vietnam to the period of the Nguyen dynasty, when the policy of the French administration was aimed at breaking cultural and economic ties between Vietnam and China, are considered. It was revealed that the layout and architecture of the garden and park ensembles of the imperial mausoleum parks were influenced by all three basic philosophical and religious teachings of China - Confucianism, Taoism and Buddhism. These teachings manifested themselves in an orderly layout with axes and symmetrical elements (Confucianism), compliance with the laws of Chinese geomancy Feng Shui (Taoism) and the unity of life and posthumous space (Buddhism). The gardens of the mausoleums in Vietnam were used for recreation and entertainment of the ruling elite, followed by the burial of the emperor and his family.El artículo está dedicado a los temas de préstamo e identidad de la cultura del jardín vietnamita en el ejemplo de los complejos de entierro de China y Vietnam. En todos los países del sudeste asiático e Indochina, donde se percibían las tradiciones de la jardinería china, los jardines de los complejos funerarios imperiales demostraron el grado de popularidad del emperador fallecido, la condición económica del imperio, modelaron la "vida" del emperador en la Más allá de la vida con el máximo uso de los principios de planificación de Feng Shui. Todos los aspectos de planificación prescritos por esta doctrina se observaron en los complejos de entierros Vietnamitas, pero con un cierto ajuste de acuerdo con sus propios puntos de vista estéticos, preferencias funcionales y percepciones de conveniencia. Las encuestas de campo realizadas por los autores de los complejos de enterramiento de Vietnam y China en las ciudades de Hue, Shenyang y las afueras de Beijing sirvieron como fuentes para el estudio. Se consideran las tendencias de la globalización en el campo de la cultura hortícola desde el período de las conquistas chinas de Vietnam hasta el período de la dinastía Nguyen, cuando la política de la administración francesa tenía como objetivo romper los vínculos culturales y económicos entre Vietnam y China. Se reveló que el diseño y la arquitectura de los conjuntos de jardines y parques de los parques del mausoleo imperial estaban influenciados por las tres enseñanzas filosóficas y religiosas básicas de China: el confucianismo, el taoísmo y el budismo. Estas enseñanzas se manifestaron en un diseño ordenado con ejes y elementos simétricos (confucianismo), el cumplimiento de las leyes de la geomancia china Feng Shui (taoísmo) y la unidad de la vida y el espacio póstumo (budismo). Los jardines de los mausoleos en Vietnam se usaron para recreación y entretenimiento de la elite gobernante, seguido del entierro del emperador y su familia.Статья посвящена вопросам заимствования и самобытности вьетнамской садовой культуры на примере погребальных комплексов Китая и Вьетнама. Во всех странах юго-восточной Азии и Индокитая, где были восприняты традиции китайской садовой культуры, сады императорских погребальных комплексов демонстрировали степень популярности усопшего императора, экономическое состояние империи, моделировали обустройство «жизни» императора в загробном мире с максимальным использованием планировочных принципов Фэн Шуй. Все планировочные аспекты, предписанные этим учением, во вьетнамских погребальных комплексах соблюдались, но с определенной корректировкой в соответствии с собственными эстетическими взглядами, функциональными предпочтениями и представлениями о целесообразности. Источниками для исследования послужили выполненные авторами натурные обследования погребальных комплексов Вьетнама и Китая - в городах Хюэ, Шэньяне и окрестностях Пекина. Рассматриваются глобализационные тенденции в области садовой культуры от периода китайских завоеваний Вьетнама до периода правления династии Нуген, когда политика французской администрации была направлена на слом культурных и экономических связей Вьетнама с Китаем. Выявлено, что планировку и архитектуру садово-парковых ансамблей императорских мавзолейных парков повлияли все три основных философско- религиозных учений Китая - конфуцианство, даосизм и буддизм, которые проявились в упорядоченной планировке с осями и симметричными элементами (конфуцианство), соблюдении законов китайской геомантии Фэн Шуй (даосизм) и единстве жизненного и посмертного пространства (буддизм). Сады мавзолеев во Вьетнаме использовались для отдыха и развлечений правящей элиты с последующим захоронением там императора и его семьи

Facile synthesis and electrical characteristics of n-SnO2/p-NiO nanowire heterojunctions

In the current work, we report a facile synthesis of n-SnO2/p-NiO nanowire heterojunctions by a drop-coating approach. The pure SnO2 and NiO nanowires (NWs) were grown by chemical vapor deposition (CVD) and hydrothermal methods, respectively. Morphology, composition and crystal structures of the NWs and heterojunctions were investigated by means of field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD), respectively. The data showed that SnO2 NWs were grown with their average diameter of 200 nm and length of about 10 mm. The NiO NWs were also synthesized with a shorter average length and smaller average diameter compared to those of the SnO2 NWs. The EDS results indicated no impurity present in both SnO2 and NiO NWs. The XRD patterns pointed out the tetragonal rutile and cubic structures of SnO2 and NiO, respectively. Interestingly, electrical properties of the NWs and heterojunctions were studied through the Keithley 2602A sourcemeter-based I-V characterizations. The results confirm the nature of the metal semiconducting oxides. The formation of the n-SnO2/p-NiO heterojunctions was certified through the rectifying behavior of the I-V curves with the rectification ratio of about 5 at ± 3V and 350 oC. The potential energy barrier between the NWs was also estimated to be about 1.16 eV. The band energy structure was also proposed to get insight into characteristics of the n-SnO2/p-NiO heterojunction

On-chip ZnO nanofibers prepared by electrospinning method for NO2 gas detection

In the present study, on-chip ZnO nanofibers were fabricated by means of the electrospinning technique followed by a calcination process at 600 oC towards the gas sensor application. The morphology, composition, and crystalline structure of the as-spun and annealed ZnO nanofibers were investigated by field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX), and X-ray diffraction (XRD), respectively. The findings show that spider-net like ZnO nanofibers with a diameter of 60 – 100 nm were successfully synthesized without any incorporation of impurities into the nanofibers. The FESEM images also reveal that each nanofiber is composed of many nanograins. The combination of experimental and calculated X-ray diffraction data indicate that ZnO nanofibers were crystallized in hexagonal wurtzite structure. For the gas sensing device application, the ZnO nanofibers-based sensors were tested with the nitrogen dioxide gas in the temperature range of 200 oC to 350 oC and concentrations from 2.5 ppm to 10 ppm. The sensing property results indicate that at the optimal working temperature of 300 oC, the ZnO nanofibers-based sensors exhibited a maximum response of 30 and 166 times on exposure of 2.5 and 10 ppm NO2 gas, respectively. The presence of nanograins within nanofibers, which results in further intensification of the resistance modulation, is responsible for such high gas response

ĐIỆN CỰC NANO CẤU TRÚC 3D - PHÂN LỚP DỊ THỂ CỦA CdS/ZnO/Pt/WO3 TRONG VIỆC NÂNG CAO HIỆU SUẤT TÁCH NƯỚC QUANG ĐIỆN HÓA

In this work, we report the synthesis of the hierarchical structure of a CdS/ZnO/Pt/WO3 electrode for photoeletrochemical water splitting application. The photoanode was synthesized via the hydrothermal and atomic layer deposition methods. The morphological and structural properties of CdS/ZnO/Pt/WO3 nanoplates were carefully investigated by using SEM, TEM, and XRD techniques. The CdS/ZnO/Pt/WO3-based photoelectrode has a photocurrent density of 8,5 mA·cm-2 and a photoconversion efficiency of 7.9% at a supplied potential of –0,85 V in a 0.5 M Na2S solution. This photocurrent density is twice higher than that of the CdS/ZnO/FTO electrode. Due to built-in potential and efficiently collecting the photo-carriers generated from the ZnO/CdS heterojunction under illumination, the CdS/ZnO/Pt/WO3 electrode exhibits enhanced performance of the photoelectrochemical cell. This is a promising approach to the synthesis of heterojunction layers of semiconductor together with nanostructures for fabricating photoelectrodes of the photoelectrochemical cell to enhance hydrogen production efficiency.Trong bài báo này, chúng tôi nghiên cứu chế tạo điện cực có cấu trúc 3D phân lớp dị thể (cây – cành – nhánh) CdS/ZnO/Pt/WO3 ứng dụng cho tách nước quang điện hóa. Điện cực được tổng hợp bằng phương pháp thủy nhiệt và lắng đọng lớp nguyên tử. Hình thái học, cấu trúc tinh thể, và thành phần nguyên tố của điện cực này được nghiên cứu bằng kính hiển vi điện tử quét (FE–SEM), kính hiển vị điện tử truyền qua (HR–TEM) và nhiễu xạ tia X (XRD). Nghiên cứu tính chất quang điện hóa của cấu trúc CdS/ZnO/Pt/WO3, chúng tôi thu được mật độ dòng quang điện là 8,5 mA·cm-2 và hiệu suất chuyển đổi năng lượng ánh sáng mặt trời thành năng lượng hydro 7,9 %% tại thế cung cấp –0,85 V trong dung dịch chất điện ly Na2S với nồng độ 0,5 mol/L. Cấu trúc 3D phân lớp này có mật độ dòng quang điện của điện cực cao hơn gấp hai lần so với các cấu trúc CdS/ZnO trên điện cực thủy tinh phủ oxit thiếc pha tạp bằng flo. Đây là một hướng tiếp cận rất hứa hẹn tổng hợp các cấu trúc nano phân lớp dị thể nhằm nâng cao hiệu quả sản xuất hydro

Utilisation d'une nanosonde de rayons X pour la caractérisation structurelle et chimique de nanofils uniques de ZnO dopés au Co par implantation ionique

The PhD dissertation focuses on the investigation of single Co-implanted ZnO nanowires using X-ray fluorescence, X-ray absorption spectroscopy, and X-ray diffraction techniques with nanometer resolution at the beamline ID22 of the European Synchrotron Radiation Facility. The ZnO nanowires were grown on p-Si (100) substrates using vapor-liquid-solid mechanism. The synthesized ZnO nanowires were doped with Co via an ion implantation process. For the first time, the combined use of these techniques allows us to study the dopant homogeneity, composition, short- and large-range structural order of individual nanowires. The nano-X-ray fluorescence results indicate the successful and homogeneous Co doping with the desired concentrations in the ZnO nanowires by an ion implantation process. The nano-X-ray absorption spectroscopy and X-ray diffraction data analyses provide new insights into the lattice distortions produced by the structural defect formation generated by the ion implantation process. These findings highlight the importance of the post-implantation thermal annealing to recover the structure of single ZnO nanowires at the nanometer length scale. Complementary microphotoluminescence and cathodoluminescence measurements corroborrate these results. In general, the methodologies used in this work open new avenues for the application of synchrotron based multi-techniques for detailed study of single semiconductor nanowires at the nanoscale.Ce travail de thèse porte sur l'analyse de nanofils de ZnO dopés au cobalt par implantation ionique, en utilisant la fluorescence des rayons X, la spectroscopie d'absorption des rayons X et les techniques de diffraction des rayons X à l'échelle nanométrique sur la ligne de lumière ID22 de l'Installation Européenne de Rayonnement Synchrotron. Les nanofils sont obtenus par croissance catalysée sur des substrats de p-Si (100). Les nanofils de ZnO synthétisés ont été dopés avec du cobalt par d'implantation ionique. Pour la première fois, l'utilisation combinée des techniques de caractérisation par rayons X citées ci-dessus nous permet d'étudier l'homogénéité de la distribution des dopants, la composition, ainsi que l'ordre structurel à courte et grande distance de nanofils individuels. Les résultats de la nano-fluorescence des rayons X indiquent que le dopage au cobalt par implantation ionique dans les nanofils de ZnO est homogène, avec les concentrations désirées. La spectroscopie d'absorption de rayons X et l'analyse des données de diffraction de rayons X fournissent de nouvelles informations sur la distorsion du réseau cristallin produite par l'introduction de défauts structuraux par le processus d'implantation ionique. Ces résultats soulignent l'importance du recuit thermique après l'implantation pour récupérer la structure des nanofils de ZnO à l'échelle du nanomètre. Les mesures complémentaires de micro-photoluminescence et cathodo-luminescence corroborent ces résultats. En conclusion, les méthodes utilisées dans cette thèse ouvrent de nouvelles voies pour l'application de mesures multi-techniques basées sur le rayonnement synchrotron pour l'étude détaillée des nanofils semi-conducteurs à l'échelle nanométrique

A REGIONAL COMPARISON OF THE MOTIVATION AND PROBLEMS OF VIETNAMESE ENTREPRENEURS

This study assesses the motivations, perceived success factors and business problems experienced by entrepreneurs in Vietnam. It also compares the results between the northern and southern regions of the country. Using data from a survey of 378 Vietnamese entrepreneurs in Hanoi and Ho Chi Minh City, results show that Vietnamese entrepreneurs are motivated by the ability to provide jobs for themselves and family members, to gain public recognition, and to prove they can successfully run a business of their own. Important perceived entrepreneurial success factors include friendliness toward customers and a good product at a good price while significant business problems include too much competition, unreliable employees and the inability to obtain both short-term and long-term capital. Results also show a number of city/regional differences in motivation, success factors and perceived success. Implications for policymakers in Vietnam and other emerging economies are also presented.Vietnamese entrepreneurs, motivation, small business, Vietnamese business

GHANAIAN AND KENYAN ENTREPRENEURS: A COMPARATIVE ANALYSIS OF THEIR MOTIVATIONS, SUCCESS CHARACTERISTICS AND PROBLEMS

Three hundred and fifty-six entrepreneurs from Kenya and Ghana were surveyed to determine their motivation for business ownership, variables contributing to their business success, and the problems they encountered. Kenyan and Ghanaian entrepreneurs indicated that increasing their income and creating jobs for themselves were leading factors motivating them to become business owners. Hard work and good customer service were cited by both Kenyan and Ghanaian business owners as critical for their success. But, compared to the Kenyan entrepreneurs, Ghanaians weighed support from family and friends and external relationship building as more important. A weak economy is the most important problem preventing entrepreneurs of both countries from achieving their goals. Ghanaian entrepreneurs were more concerned about the inability to obtain capital, while Kenyan entrepreneurs were more concerned about government regulations and problems related to business location.African entrepreneurs, motivation, business success, African business problems

A conformal multi-port MIMO patch antenna for 5G wireless devices.

This paper presents a multiple-input-multiple-output (MIMO) antenna array with low-profile and flexible characteristics. Multiple microstrip patches are arranged in the E-plane configuration and decoupled by shorted quarter-wavelength stubs. The antenna has a small element spacing of 0.032 λ, where λ is a free-space wavelength at the center frequency. To demonstrate the feasibility of the proposed concept, a 1 × 4 MIMO array prototype is fabricated. The measured results on the fabricated prototype demonstrate that the MIMO antenna has good operation features at 4.8 GHz with a reflection coefficient of less than -10 dB and an isolation of better than 20 dB. Besides, good radiation patterns and broadside gain of around 4.5 dBi are also attained. The antenna also works in the bending mode and has the capability of extending to large-scale MIMO arrays. Such attractive features prove the utility of the proposed antenna in various modern electronic devices