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The paper aims to investigate the determinants of China’s daily intervention in the foreign exchange market since the 2005 reform aimed at moving the Renminbi (RMB…
The paper aims to investigate the determinants of China’s daily intervention in the foreign exchange market since the 2005 reform aimed at moving the Renminbi (RMB) exchange rate regime towards greater flexibility.
The paper uses bivariate probit models to test whether China’s intervention decision is driven by three sets of factors, comprising Model I (basic model), Model II and Model III.
Evidence from the models suggests that medium-term Chinese interventions tend to be leaning-against-the-wind, whereas long-term interventions are leaning-with-the-wind. Furthermore, by analyzing exchange rate volatility, this paper finds that intervention is used by the Chinese central bank to ensure that there are no big swings in the RMB exchange rate.
The paper will be of value to other researchers attempting to understand the policy of the central bank and, in particular, the factors that can lead to interventions during periods of financial crisis.
Alginate fiber with a breaking tenacity of up to 2.32 cN/dtex is prepared by spinning a sodium alginate solution in a coagulating solution of CaCl2 aqueous solution…
Alginate fiber with a breaking tenacity of up to 2.32 cN/dtex is prepared by spinning a sodium alginate solution in a coagulating solution of CaCl2 aqueous solution followed by multi-roller drawing. Preparation parameters such as sodium alginate concentration, coagulant concentration and coagulation temperature, which affect the fiber tenacity, are investigated with an orthogonal test design, and the best spinning process is found with a coagulating 5% sodium alginate solution in 4% CaCl2 at 40°C. The morphology, degree of crystallinity, thermal stability and the combustion performance of this alginate fiber are investigated by scanning electron microscopy (SEM), infrared (IR), X-ray diffraction (XRD), Thermo gravimetric Analysis (TGA) and Cone Calorimeter. Using the centrifugal dewatering method, the absorption capacity of this alginate fiber is determined, and has a capacity of 13.01 grams of man-made blood per gram. The test results show that fibers have an irregular cross-section without a thicker cortex and uniform longitudinal surface with grooves. The combustion property results demonstrate that the fiber has a self-flameretarding property.
Glutaraldehyde is chosen as a novel non-formaldehyde durable press finish for cotton fabrics in this investigation. The optimum technique conditions and influences of…
Glutaraldehyde is chosen as a novel non-formaldehyde durable press finish for cotton fabrics in this investigation. The optimum technique conditions and influences of glutaraldehyde concentration and catalysts, pH value, and curing conditions for the properties of the finished fabric have been investigated in detail. The finished fabric achieves the best performance with a pH value in the range of 4 to 4.5 for the glutaraldehyde finishing bath, magnesium chloride as the catalyst, and curing conditions of 160oC for 3 minutes. In addition, in contrast to low formaldehyde resin and non-formaldehyde finishers sold in the market, the wrinkle recovery angle of the fabric finished with glutaraldehyde is better than that finished with FREEREZ NFR (DHDMI), but not as satisfactory as that finished with FREEREZ 880 (low formaldehyde 2D). However, its strength is greater than the fabric finished with FREEREZ 880, but less so than that finished with FREEREZ NFR.
The purpose of this paper is to examine the performance of a fastener composite coating system, sherardized (SD) coating/zinc-aluminum (ZA) coating whether it has good…
The purpose of this paper is to examine the performance of a fastener composite coating system, sherardized (SD) coating/zinc-aluminum (ZA) coating whether it has good performance in marine environment.
In this paper, SD coating was fabricated on fastener surface by solid-diffusion method. ZA coating was fabricated by thermal sintering method. Corrosion behaviours of the composite coating were investigated with potentiodynamic polarization curves, open circuit potential and electrochemical impedance spectroscopy methods.
Neutral salt spray (NSS) and deep sea exposure tests revealed that the composite coating had excellent corrosion resistance. Polarization curve tests showed that corrosion current density of the sample with composite coating was significantly decreased, indicating an effective corrosion protection of the composite coating. OCP measurement of the sample in NaCl solution demonstrated that the composite coating had the best cathodic protection effect. The good corrosion resistance of the composite coating was obtained by the synergy of SD and ZA coating.
SD/ZA coating can be used in marine environment to prolong the life of carbon steel fastener.
SD/ZA composite coating can reduce the risk and accident caused by failed fastener, avoid huge economic losses.
A new kind of composite coating was explored to protect the carbon steel fastener in marine environment. And the composite coating has the long-term anti-corrosion performance both in simulated and marine environment test.
The purpose of this work was to express a facile method to fabricate microcapsules containing linseed oil with melamine-urea-formaldehyde (MUF) shell in the presence of…
The purpose of this work was to express a facile method to fabricate microcapsules containing linseed oil with melamine-urea-formaldehyde (MUF) shell in the presence of polyvinylpyrrolidone (PVP) as an emulsifier. These microcapsules may be used in self-healing coating formulations.
In this work, different types of PVP (i.e., PVP with different molecular weights or K values) were used as emulsifiers and colloid protectors to encapsulate linseed oil in an MUF shell. Moreover, the effect of agitation rate on the morphology of the microcapsules was investigated. Microcapsule morphology and particle size distribution were evaluated using optical microscopy and scanning electron microscopy. Thermal studies were performed using a thermo-gravimetric analysis technique and chemical structure of materials was characterized by using Fourier transform infrared analysis.
In this work, microcapsules with a regular spherical shape and a shell thickness of about 330 nm were fabricated. The results revealed that the use of PVP in the fabrication of MUF could facilitate the synthesis process by eliminating the necessity of pH control during the reaction. In fact, the pH of the reaction media must be precisely controlled in conventional processes. The yield of microencapsulation was found to be 86.5 per cent when a high molecular weight of PVP (PVP K-90) was used. It was also found that the surface morphology of microcapsules became smoother when PVP K-90 was used. The results showed that the surface roughness and the average particle size decreased with an increase in stirring intensity. Mean diameter of the prepared microcapsules ranged from 34 to 346 μmin for various synthesis conditions.
This work is limited to the encapsulation of a hydrophobic liquid (such as linseed oil) by an in situ polymerisation of amino resins.
The presented results can be used by researchers (in academia and industry) who are working in the field of fabrication microcapsules, in various applications such as pharmaceuticals, electrophoretic displays, textiles, carbonless copy papers, cosmetics, printing and self-healing materials.
PVP is considered as an environmentally friendly emulsifier. Therefore, this process is less harmful to the environment. In addition, the prepared microcapsules may be used in self-healing coatings, which helps in reducing maintenance costs for buildings and steel structures.
Ethylene maleic anhydride and styrene maleic anhydride are usually used as emulsifiers in conventional methods for the preparation of amino resin microcapsules. These methods require an intensive and precise pH control to obtain favourable microcapsules, while in the present research, a facile method was used to fabricate MUF microcapsules containing linseed oil without needing any pH control during the reaction.