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With the rapid development of the experience economy and sharing economy, bed and breakfast (B&B) accommodation, favoured by more and more tourists, has become an indispensable component of tourism...

Ionic liquids have a great potential in capture and separation of carbon dioxide (CO2), and the solubility of CO2 in ionic liquids is one of key data for engineering applications. In this paper, th...

Neural network algorithms are gradually applied to the field of chemical informatics. In this paper, the neural network models are used to predict the properties of compounds based on Molecular Inf...

Two-dimensional numerical simulations were performed using the FLUENT code to investigate the impacts of the shape and height of building roofs on flow and pollutant dispersion inside an isolated street canyon. The numerical model was validated against wind tunnel measured data. Five different roof shapes (vaulted, trapezoidal, slanted, upward wedge-shaped, and downward wedge-shaped roofs) and three different roof heights ( = 1/6, 1/3, and 1/2, where is the roof height and H is the building height) were considered in the simulations. The numerical results revealed that the vortical flow structure and pollutant distribution within an isolated canyon depend significantly on the shape and height of building roofs. A large unique clockwise vortex is established in the canyon, and thus the pollutants accumulate in the leeward side of the canyon for the vaulted and downward wedge-shaped roofs at = 1/6, 1/3, and 1/2, the trapezoidal roof at = 1/6 and 1/3, and the slanted and upward wedge-shaped roofs at ...

Many epidemiological studies have evaluated associations of platelet glycoprotein receptor alpha2beta1 integrin (ITGA2) and glycoprotein IIIa (ITGB3) gene polymorphisms with diabetic retinopathy (DR), but the published data are inconclusive. The aim of the present study was to assess the associations by using meta-analysis.A comprehensive electronic search (PubMed, EMBASE, Elsevier Science Direct, CNKI and Wanfang) was carried out until 31 August 2013. Odds ratios (ORs) and its 95% confidence intervals (CIs) were used to assess the strength of the associations.Nine studies including 1678 cases and 1329 controls were included in the meta-analysis. Meta-analysis was performed for ITGA2 gene BgI II polymorphism (7 studies including 758 cases and 570 controls) and ITGB3 gene PlA1/A2 polymorphism (4 studies including 1047 cases and 861 controls). Significant associations were found for BgI II (+ versus -: OR = 1.42, 95% CI = 1.06-1.90, p = 0.02; +/- + +/+ versus -/-: OR = 1.46, 95% CI = 0.99-2.15, p = 0.06; +/+ versus -/- + +/-: OR = 1.90, 95% CI = 1.35-2.67, p = 0.0003) and PlA1/A2 (A2 versus A1: OR = 0.74, 95% CI = 0.52-1.07, p = 0.11; A1A2 + A2A2 versus A1A1: OR = 0.80, 95% CI = 0.64-0.99, p = 0.04; A2A2 versus A1A1 + A1A2: OR = 0.45, 95% CI = 0.27-0.75, p = 0.002) polymorphisms.This meta-analysis demonstrates that DR is associated with ITGA2 BgI II and ITGB3 PlA1/A2 polymorphisms.

Nuclear magnetic resonance (NMR) is a robust method for the analysis of molecular complex structures, and the measurement of the nuclear spin–spin coupling constant is the key. In this paper, based...

A two-dimensional numerical model for evaluating the wind flow and pollutant dispersion within a street canyon was first developed using the FLUENT code, which was then validated against a wind tunnel experiment. Then, the effects of the upstream building width and upwind building arrangement on the airflow and pollutant dispersion inside an isolated street canyon were investigated numerically. The numerical results revealed that: (1) the in-canyon vortex center shifts downwards as the upstream building width increases; (2) the recirculation zone covers the entire upstream building roof for the cases when W/H = 0.5, 1.0, 1.5, and 2.0 (W is the upstream building width and H is the building height), whereas the flow reattaches the upstream building roof for the cases when W/H = 2.5 and 3.0; (3) when the upstream building width is shorter than the critical width WC (= 2H), an increase in the upstream building width leads to an increase in the pollution level on the leeward wall of the canyon and a decrease i...

Particle degradation can be a significant issue in particulate solids handling and processing, particularly in pneumatic conveying systems, in which high-speed impact is usually the main contributory factor leading to changes in particle size distribution (comparing the material to its virgin state). However, other factors may strongly influence particles breakage as well, such as particle concentrations, bend geometry, and hardness of pipe material. Because of such complex influences, it is often very difficult to predict particle degradation accurately and rapidly for industrial processes. In this article, a general method for evaluating particle degradation due to high-speed impacts is described, in which the breakage properties of particles are quantified using what are known as “breakage matrices.” Rather than a pilot-size test facility, a bench-scale degradation tester has been used. Some advantages of using the bench-scale tester are briefly explored. Experimental determination of adipic acid has b...

The models of the nonlinear radial flow for the finite fractal reservoirs including a quadratic gradient term are presented. Generalized orthogonal transform is given by using the orthogonality of eigenfunction. We give the exact solution in real space for flow equation including quadratic gradient term for both constant-rate and constant-pressure production cases from in a finite system by using generalized orthogonal transform. Both closed and constant pressure outer boundary conditions are considered. Moreover, the difference between the nonlinear pressure solution and linear pressure solution is analyzed, and the difference may be reached about 10% in the long time. The effect of the quadratic gradient term in the large time well test may be considered.

Aqueous pressure oxidation has been developed to a viable technology. It has found extensive commercial applications in mineral industry. Numerous pressure processing plants have been constructed worldwide for production of nickel, cobalt, copper and zinc from ores, concentrates and other metallurgical intermediates or secondary materials and for pretreatment of gold refractory ores. Successful operation of these plants provides hydrometallurgy with experience and confidence for its potential development and applications. This paper is intended to review the development and applications of pressure oxidation technology and the chemistry involved as well.

A greal deal of effort has been directed towards the development of economically and technically feasible processes for the chemical oxidation of iron sulfides. Such processes applied commercially or under active development, including roasting, and sulfate-, nitrate-, chloride- and alkaline-based aqueous oxidation processes, are outlined in this paper.

Oxidized copper ores are exhibiting increasingly their importance as copper resources as worldwide high grade copper sulfide deposits become depleted. Extensive chemical and technological efforts have been made to meet the demand of exploitation of such copper resources. This paper reviews the processes and modifications developed in the last three decades as the results of these efforts in flotation, hydrometallurgy and combined mineral processing and metallurgy processes. The emphasis is put on the refractory oxidized ores, with a special reference to a copper deposit at Tangdan of Dongchuan mine in Yunnan province of China.