Creating nano composite TiO2.Fe2O3/laterite material applying to treat arsenic compound in groundwater: Research article

This article presents nano composite TiO2.Fe2O3/laterite materials, which were successfully prepared by hydrometallurgical method. The materials were modified using urea as the nitrogen source. The particles size of the materials is from 20-30 nanometers. The obtained materials can not only absorb arsenic compounds but also enhance the ability of converting As (III) or As (V) into Aso, which is removed from solution. Arsenic removal efficiency of these materials is high. Using sunlight in a hydraulic retention time, about 180 minutes, the arsenic value at the inflow was about 10 mg/L but the outflow was negligible. Covering TiO2.Fe2O3 nano on laterite have brought high economical efficiency, on one hand, it saved material and on the other hand, it can be continuously operated without the centrifugal separation of the nano material.Bài báo này giới thiệu về phương pháp điều chế vật liệu nano TiO2.Fe2O3 biến tính nitơ được phủtrên đá ong bằng phương pháp thủy luyện. Vật liệu nano thu được có kích thước 20-30 nm. Vật liệu thu được không những có khả năng hấp phụ các hợp chất của asen mà còn có khả năng khử As (III) hoặc As (V) thành Asokhi được chiếu sáng. Sử dụng ánh sáng mặt trời chiếu vào hệ thống xử lý trong thời gian 180 phút có thể loại bỏ được gần như hoàn toàn asen ra khỏi nước mặc dù hàm lượng đầu vào là 10 mg/l. Việc phủ vật liệu TiO2.Fe2O3 nano lên đá ong đã mang lại hiệu quả kinh tế cao, một mặt nó tiết kiệm được vật liệu, mặt khác, vật liệu có thể sử dụng một cách liên tục mà không cần phải tách bằng phương pháp ly tâm

An inquiry into the determinants of Vietnamese product export

Export led growth is the model of economic development that Vietnam has been following. While there are a great number of studies on the determinants of aggregate export of Vietnam, there are few that analyze the impacts of different factors on the export of different product groups. This paper aims at filling this gap in research on international trade of Vietnam. The results show that the fast GDP growth of Vietnam, the large population of importing countries, the wide economic gap between Vietnam and the importing countries, the depreciation of domestic currency, the free trade agreements that Vietnam signed and the shared border with the importing countries contribute to the increase of Vietnam’s export of all product groups. In contrast, the GDP of importing countries and population of Vietnam have no clear impacts on the export of any product groups.

A Unified Approach to Convex and Convexified Generalized Differentiation of Nonsmooth Functions and Set-Valued Mappings

In the early 1960's, Moreau and Rockafellar introduced a concept of called \emph{subgradient} for convex functions, initiating the developments of theoretical and applied convex analysis. The needs of going beyond convexity motivated the pioneer works by Clarke considering generalized differentiation theory of Lipschitz continuous functions. Although Clarke generalized differentiation theory is applicable for nonconvex functions, convexity still plays a crucial role in Clarke subdifferential calculus. In the mid 1970's, Mordukhovich developed another generalized differentiation theory for nonconvex functions and set-valued mappings in which the "umbilical cord with convexity" no longer exists. The primary goal of this paper is to present a unified approach and shed new light on convex and Clarke generalized differentiation theories using the concepts and techniques from Mordukhovich's developments

THE IMPACT OF DATA SECURITY ON THE INTENTION OF VIETNAMESE CONSUMERS TO USE E-WALLETS

E-wallets are used as a form of payment that brings many benefits to users. This article studies the impact of data security on consumer intentions to use e-wallets in the rapidly growing economy of Vietnam. The data consist of 236 observations from a survey of consumers in Vietnam. Covariance-based structural equation modeling (CB-SEM) was employed to test the proposed hypotheses. Research results show that security trust has the greatest impact on the intention to use e-wallets, followed by perceived privacy risk, social influence, and information sensitivity. The study also reveals the role of privacy policies and security concerns in consumer intentions to use e-wallets. Based on the research results, the study provides recommendations for consumers, e-wallet providers, and governmental agencies to increase awareness of and responsibility for information security among the consumers who use e-wallets

Linking Relationship Marketing to Customer Loyalty in The E-Banking Context: The Central Role of Customer Satisfaction

This research examines the interrelationships between relationship marketing, customer satisfaction and customer loyalty in e-banking’s context. The study was conducted in two phases: In-depth interviews and a quantitative survey with a sample of 690 Vietnamese individual and corporate e-banking customers. The research results show that customer satisfaction mediates the impact of relationship marketing on customer loyalty among individual customers. Meanwhile, instead of customer satisfaction, relationship marketing significantly and directly contributes to the loyalty of the corporate customer group. The significance and magnitude of the effects that the five dimensions of relationship marketing’s effectiveness have on customer satisfaction and loyalty, which include the banks’ commitment, customer experience, process-driven approach, service reliability and application of technology, are also different between the two customer segments. This study theoretically contributes to the research stream regarding the mechanism underlying the relationship between relationship marketing’s effectiveness and customer loyalty in the e-banking context, and proposes practical implications for commercial banks to effectively apply relationship marketing in the virtual business environment