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1.
Two sets of variable oil length, alkyd resins modified by sunflower oil (SOA) and by rapeseed oil (ROA), were evaluated in offset formulations with mineral oils as diluent. The more suitable alkyds for this kind of application were determined. In a second experiment, hydrocarbon solvents were substituted by the fatty acid methyl esters derived from rapeseed oil or sunflower oil to produce ecologically friendly offset printing inks. Finally, the ROA and the SOA were associated with the methyl esters derived from the same vegetable oil. New properties of the varnishes composed of a vegetable diluent were evaluated. The quickset formulations with the methyl esters do not need important modifications, as opposed to the heatset formulations.  相似文献   

2.
Most existing techniques for regulating the ink flow in offset presses rely on density measurements carried out on specially printed patches. In the present contribution, we develop a methodology to deduce ink thickness variations from spectral measurements of multichromatic halftone patches located within the printed page. For this purpose, we extend the Clapper‐Yule spectral reflectance prediction model by expressing the transmittance of the colorants composed of superposed inks as a function of the ink transmittances and of fitted ink layer thicknesses. We associate to each ink an ink thickness variation factor. At print time, this ink thickness variation factor can be fitted to minimize a difference metric between predicted reflection spectrum and measured reflection spectrum. The ink thickness variations deduced from multichromatic halftones allow to clearly distinguish between normal ink volume, reduced ink volume, or increased ink volume. This information can then be used for performing control operations on the printing press. © 2009 Wiley Periodicals, Inc. Col Res Appl, 34, 432–442, 2009  相似文献   

3.
Colors can be characterized by three main attributes: hue, value, and saturation. But colors also exhibit other phenomenological qualities. In this study, we identify one such secondary attribute of color: perceived density. We discuss the prevalence of dense colors in Japan starting from the “48 Teas and 100 Mice” colors of the Edo period, and develop the concept of perceived density through this aspect of Japanese color preference. When vivid colors were forbidden to commoners during the Edo period, subtle variations of brownish and grayish colors were created. These colors with base tones were not salient, yet they looked dense. Muted colors with paradoxical richness are still common in Japan today. Japanese commodity design often uses muddy colors with white or gray undertones, and deep colors with black undertones. Together they form distinct groupings of relatively dense color. The perceived density of color corresponds to how dense and filled, or thin and airy a color appears. Colors of higher perceived density appear to be more packed and to have mass. Perceived density of color is unusual in that it does not have a monotonic relationship with one of the primary perceptual attributes. High apparent density is observed in a central region of an equi‐hue plane where value or saturation are at intermediate values. We consider two possible explanations of how high values of density can coincide with middling values of value and saturation: characteristics of the spectral reflectance curves, or the complexity of the neural signals that underlie the emergent property.  相似文献   

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The pharmaceutical manufacturing sector needs to rapidly evolve to absorb the next wave of disruptive industrial innovations—Industry 4.0. This involves incorporating technologies like artificial intelligence and 3D printing (3DP) to automate and personalize the drug production processes. This study aims to build a formulation and process design (FPD) framework for a pharmaceutical 3DP platform that recommends operating (formulation and process) conditions at which consistent drop printing can be obtained. The platform used in this study is a displacement-based drop-on-demand 3D printer that manufactures dosages by additively depositing the drug formulation as droplets on a substrate. The FPD framework is built in two parts: the first part involves building a machine learning model to simulate the forward problem—predicting printer operation for given operating conditions and the second part seeks to solve and experimentally validate the inverse problem—predicting operating conditions that can yield desired printer operation.  相似文献   

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The aim of this work was to degrade pharmaceuticals such as amoxicillin (AMX), ceftriaxone (CTX), and Telebrix (TLX) by electro-Fenton (EF) process using a dimensionally stable anode (DSA) cathode, Pt-RuO2-IrO2 (PRI). For this purpose, the optimal conditions of degradation, the pseudo-first-order kinetics, the current efficiency, the electrochemical energy consumption (EEC), and the energy cost have been investigated. A spectrophotometric analysis technique has been developed. It is a simple, fast, linear, reliable, and selective technique with LOD = 0.013 g/L and LOQ = 0.04 g/L. The optimum working conditions determined are: Fe2+ = 0.2 mM, pH = 3, j = 20 mA/cm2, and (Pt, PRI) as electrode pair. Under these conditions, the EF process leads to a conversion of the parent compound. In addition, the degradation of compounds by EF follows pseudo-first-order kinetics. The EEC for the degradation of 1 kg COD of an organic compound is 99.48, 66.86, and 50.32 kWh kg COD−1 for AMX, CTX, and TLX respectively. The energy cost for processing these compounds is $4.92 (AMX), $10.03 (CTX), and $7.55 (TLX) with current efficiencies between 26% and 51%. Ultimately, the EF process using PRI at the cathode can be used for the treatment of real wastewater from health centres under optimal conditions.  相似文献   

8.
Compared to the equiatomic or near-equiatomic NiTinol alloys, Ni-rich NiTi alloys are suitable to be employed in structural applications as they exhibit higher hardness and are dimensionally stable. This research aimed to process two different grades of Ni-rich NiTi alloys, 58NiTi and 60NiTi, from Ni–Ti powder mixtures having about 58 wt.% and 60 wt.% Ni, respectively. This was performed by a laser powder bed fusion technique. At the first stage of this research, the printability of the used powder mixtures was investigated by applying different sets of printing parameters. Two appropriate sets were then selected to print the samples. Microstructural study of the printed parts revealed the existence of inhomogeneity in the microstructures. In addition, depending on the applied set of parameters, some amounts of cracks and pores were also present in the microstructure of these parts. Postprinting hot isostatic pressing procedures, performed at different temperatures, were developed to cause the reaction of phases, homogenize the parts, and possibly eliminate the existing flaws from the samples. Effects of these applied treatments on the microstructure, phase composition, density, dimensional integrity, and hardness of parts were sequentially studied. In essence, 58NiTi and 60NiTi parts having phase compositions complying with those of the equilibrium phase diagram were obtained in this research. However, the mentioned cracks and pores, formed in the microstructure of as-printed parts, could not be fully removed by postprocessing treatments.  相似文献   

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