Some ferrocene containing aromatic azo polyesters were prepared by condensing 1,1-ferrocenedicarbonyl chloride with different azo groups containing aromatic diols, which were synthesized by diazotization coupling reaction from aromatic diamines. The polymeric products were separated as two portions on the basis of their solubility and subsequently characterized by their elemental analysis and FTIR spectral studies. Thermal properties of the products were measured by differential scanning calorimetry and thermogravimetry and the activation energies of pyrolysis were calculated using Horowitz and Metzger's method. The molecular weights of the soluble portions were determined by gel permeation chromatography (GPC) and these portions were also characterized by their inherent viscosities and UV-Vis spectroscopic studies. 相似文献
This study aims to address the paradigms of consumers’ adoption behavior for mobile government, posits the factors which pursue citizens’ intention to adopt mobile government services, and reveals the impact of cultural dimensions in perceiving driving factors of mobile government adoption. The mobile government adoption model was developed and tested among users of three different countries, namely Bangladesh, Canada, and Germany. The finding suggests the rationale that cross-cultural differences impact consumers’ perception of mobile government adoption behavior. 相似文献
The study has focused on electricity generation from organic acid-rich bio-substrate like star fruit (Averrhoa carambola). The sap of star fruit was selected as an electrolyte due to the presence of significant amounts of organic acids such as citric acid and ascorbic acid. To preserve the sap, 2% phenol by volume was used to reduce the growth of microorganisms, and the addition of phenol did not affect the initial pH. It was observed that due to an increase in the electrode surface area, reaction rate and current generation had been amplified. Internal resistance also decreased rapidly because of the large electrode surface area. Furthermore, internal resistance was the significant barrier in electricity generation, which was also successfully controlled by the baffle flow agitation system. Moreover, the baffle flow agitation system reduces the formation of dead zones and increases the total dissolved solids inside the electrochemical cell compartments during operation. 相似文献
The mobile-Government (mGov) service system is conducted through an open network, and it is virtual. This service mode and pattern change inevitably necessitates a behavioral change in citizen attitudes and intentions. Nevertheless, this new pattern of service delivery through mGov has hardly been systematically investigated by any researchers. The objective of this current research is twofold. First, we attempt to reveal the sources of beliefs for developing intention toward the mGov (ITM) system. Then, as the second objective, we investigate cultural influence as the reason for a difference in consumer attitudes and intentions toward mGov. In this regard, the empirical study was conducted in Bangladesh and the USA, which have potential differences in the cultural traits listed by Hofstede. From our statistical analysis, we have identified the sources of beliefs for both Bangladeshi and USA consumers. We observed clear differences in sources of beliefs and their influence on attitudes leading to intention, which demonstrates support for our second objective which was designed to verify the cultural impacts on belief-attitude relations. We understand that these different sources of beliefs influence cognitive, affective, and connative attitudes toward mGov in different ways. 相似文献
Today, urbanised people spend most of their time in indoor environments, and the risk of exposure to toxic materials in an indoor environment is of great concern. This paper considers sources for the inhalation risk of aerosol sprays by measuring the particle size distributions of some of the most popular products that are commercially available in Bangladesh, and examines the degree of toxicity and the health risk via the respirability of the products. Results show that thoracic and respirable fractions of the suspended particulate matter are present in the tested samples and hence the spray products may pose a significant health risk. 相似文献
Efforts have been devoted to synthesize and characterize processable polymers with desired properties. Herein, four different series of aromatic and aliphatic terpolyamides were prepared via solution phase polycondensation of 4,4′-oxydianiline and hexamethylenediamine (HMDA) with various diacids chlorides (isophthalyol dichloride, terepthalyol dichloride, 1, 1′-ferrocene dicarboxylic acid chloride and trans-azobenzene-4, 4′-dicarbonyl chloride). The structural, morphological and physico-chemical nature of as prepared polymers was explored by Fourier-transform infrared spectroscopy, scanning electron microscopy, thermal analysis (TGA and DSC), and wide-angle x-ray diffraction. Moreover, an aliphatic diamine was incorporated in varying concentration as a flexible methylene spacer and the effect of its concentration on the properties of polyamides was also studied. Changes in various physico-chemical properties such as solubility, inherent viscosity, surface morphology and flame retarding behaviour were investigated. Marked difference in morphology and solubility was observed with the change in the ratio of segments in the chain. Inherent viscosities of polymers ranged from 1.8052–1.6274 dl/g indicating reasonably moderate molecular weights. Interestingly, ferrocene based aromatic polymers were more thermally stable (Tg 260 °C, Ti 310 °C, Th 525 °C, Tf 720 °C, for PF0), and also found to exhibit best flame retarding behavior (limiting oxygen index value for PF0is LOI 33.15%).
The purified crude lipid of Psoralia corylifolia seeds was subjected to lipid class and fatty acid analysis by thin layer and gas chromatography. The lipid classes identified were triacyl glycerol, free fatty acid, diacyl glycerol, mono acyl glycerol, hydrocarbon-waxester and polar lipid fractions. Most of the fractions were found to contain high level of C18:1 while C18:0, C18:3 and C20:0 were also found to be present in all the lipid fractions. It has been observed that the diacyl and monoacyl glycerol fractions contain significant amounts of C14:0 and C18:0 while the hydrocarbon-waxester fraction was rich in C22:0. The polar lipids contain high level of C18:3 and low level of C18:1 as compared to other lipid fractions. The fatty acid composition of the whole oil was also determined and found to be similar to other fractions. Unidentified long chain fatty acids were also present in significant amounts in all the lipid fractions. 相似文献
Tungsten inert gas (TIG) welded joints between Zircaloy-4 and stainless steel 304L have been studied by scanning electron
microscope (SEM) having energy dispersive system (EDS) as an attachment. Intermetallic compound Zr(Cr, Fe)2 and Zr2Fe–Zr2Ni eutectic phase have been observed in the molten zone. The surface area occupied by intermetallic compound Zr(Cr, Fe)2 is about twice compared to Zr2Fe–Zr2Ni eutectic phase. The shape of the intermetallic compound is rod like. The phases were also identified by using X-ray diffraction
(XRD) technique. EDS and XRD results are quite in agreement. 相似文献