Facile synthesis of 3D Fe2O3 nanostructures: sponge-like cube shape and bird nest-like architecture

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

Equality of ordinary and symbolic powers of Stanley-Reisner ideals

This paper studies properties of simplicial complexes for which the m-th symbolic power of the Stanley-Reisner ideal equals to the m-th ordinary power for a given m > 1. The main results are combinatorial characterizations of such complexes in the two-dimensional case. It turns out that there exist only a finite number of complexes with this property and that these complexes can be described completely. As a consequence we are able to determine all complexes for which the m-th ordinary power of the Stanley-Reisner ideal is Cohen-Macaulay for a given m > 1.Comment: 19 page

Tính chất đàn hồi và nhiệt động lực học của nano tinh thể cadmi selenide

The elastic and thermodynamic of zincblende CdSe nano crystals have been investigated by first-principles calculations based on density functional theory (DFT). The type of CdSe structure was optimized from the experimental parameter values. The mechanic characterization was determined based on the computed values of independent elastic constants C11, C12, and C44. The temperature dependence of a series of thermodynamic properties functions such as free energy, entropy, enthalpy, and heat capacity are calculated and analyzed in detail.Các tính chất đàn hồi và nhiệt động lực học của nano tinh thể (NC) cadmi selenide (CdSe) có cấu trúc zincblend đã được nghiên cứu trên cơ sở tính toán nguyên tắc ban đầu bằng phương pháp phiếm hàm mật độ (DFT). Thông số cấu trúc tinh thể được tối ưu hóa phù hợp với giá trị từ kết quả thực nghiệm. Các hệ số đặc trưng cho tính chất cơ học được xác định thông qua các giá trị tính toán ba hệ số đàn hồi độc lập C11, C12, C44. Sự phụ thuộc vào nhiệt độ của một số hệ số đặc trưng cho tính chất nhiệt động lực học như năng lượng tự do, entropy, entanpy và nhiệt dung cũng được khảo sát và phân tích một cách chi tiết

Ownership, technology gap and technical efficiency of small and medium manufacturing firms in Vietnam: A stochastic meta frontier approach

The ownership - efficiency relationship in a firm has always been an important topic. In this paper, we focus on the state owned versus non-state-owned status of Vietnamese manufacturing firms, to shed light into the relationship between these two variables when using a more state-of-the-art method as a stochastic meta-frontier method. Applying the method for two periods: one during the global economic crisis and the other after the end of the crisis, the study determines that in both periods, there was a strong evidence that non-state-owned firms performed much better than state owned counterpart. We also found that the difference became even larger during the harsh time and sub-industries with non-state-owned firms could outperform the state-owned firms, significantly

Phase Structure of Bose - Einstein Condensate in Ultra - Cold Bose Gases

The Bose - Einstein condensation of ultra - cold Bose gases is studied by means of the Cornwall - Jackiw - Tomboulis effective potential approach in the improved double - bubble approximation which preserves the Goldstone theorem. The phase structure of Bose - Einstein condensate associating with two different types of phase transition is systematically investigated. Its main feature is that the symmetry which was broken at zero temperature gets restore at higher temperature

Trends in, projections of, and inequalities in non-communicable disease management indicators in Vietnam 2010–2030 and progress toward universal health coverage : a Bayesian analysis at national and sub-national levels

Background: Movement towards Universal Health Coverage (UHC) can improve health services, risk factor management, and inequality in non-communicable diseases (NCD); conversely, prioritizing and monitoring NCD management can support pathways to UHC in resource-limited settings. We aimed to estimate trends in NCD management indicators in Vietnam from 2010, and projections to 2030 at national and sub-national levels; compute the probability of reaching UHC targets; and measure inequalities in NCD management indicators at demographic, geographic, and socio-economic levels. Methods: We included data of 37,595 households from four nationally representative surveys from 2010. We selected and estimated the coverage of NCD health service and risk management indicators nationally and by six sub-national groups. Using Bayesian models, we provided trends and projections and calculated the probability of reaching UHC targets of 80% coverage by 2030. We estimated multiple inequality indices including the relative index of inequality, slope index of inequality, and concentration index of inequality, and provided an assessment of improvement in inequalities over the study period. Findings: Nationally, all indicators showed a low probability of achieving 2030 targets except sufficient use of fruit and vegetables (SUFV) and non-use of tobacco (NUT). We observed declining trends in national coverage of non-harmful use of alcohol (NHUA), sufficient physical activity (SPA), non-overweight (NOW), and treatment of diabetes (TOD). Except for SPA, no indicator showed the likelihood of achieving 2030 targets at any regional level. Our model suggested a non-achievement of 2030 targets for all indicators in any wealth quintile and educational level, except for SUFV and NUT. There were diversities in tendency and magnitude of inequalities with widening gaps between genders (SPA, TOD), ethnic groups (SUFV), urban-rural areas (TOH), wealth quintiles, and educational levels (TOD, NUT, NHUA). Interpretation: Our study suggested slow progress in NCD management at the national level and among key sub-populations in Vietnam, together with existing and increasing inequalities between genders, ethnicities, geographic areas, and socioeconomic groups. We emphasised the necessity of continuously improving the healthcare system and facilities, distributing resources between geographic areas, and simultaneously integrating economic, education, and gender intervention and programs. Funding: None. © 2022 The Author(s