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51.
基于伊犁盆地伊宁凹陷钻/测井、露头、地震剖面等资料,运用平衡剖面恢复技术,在对伊宁凹陷主干剖面构造演化恢复的基础上,开展构造特征研究工作。研究表明:伊宁凹陷具有"北断南超、南北分带"的构造格局和"北强南弱"的构造变形特点;自二叠纪完全进入陆内发展阶段以来,该区经历了二叠纪末、三叠纪末侏罗纪初、侏罗纪末以及新近纪末4个主要挤压形变期,其中二叠纪末期盆地在东西方向上的挤压变形较为强烈,之后减弱并逐渐发展为以南北向挤压为主,新近纪末为伊宁凹陷南北向主体结构的主要定型期;在南北向为主的挤压应力背景下,伊宁凹陷及周边对冲、逆冲构造发育,形成了以挤压构造为主的构造样式。 相似文献
52.
The quality of recycled process water is an important issue in the flotation of Cu–Mo ores. Processing of Cu–Mo ores includes two steps: a bulk flotation where molybdenite is recovered together with Cu sulfides, and a subsequent selective flotation step where molybdenite is separated from depressed copper sulfides. Flocculants are usually employed in the middling thickeners in the copper plant, and in the Cu–Mo bulk concentrate ahead of the molybdenite plant. However, the floatability of molybdenite, similarly to other naturally hydrophobic minerals, is highly sensitive to the presence of both natural and synthetic polymers. In this work flotation tests demonstrate that conventional flocculants, high-molecular weight anionic polyacrylamides (PAM), are strong molybdenite depressants. Low-molecular weight shear degraded polyacrylamides in spite of losing flocculation efficiency maintain depressing ability for molybdenite. Also a non-ionic flocculant, polyethylene oxide (PEO), has been studied in this project. Our results indicate that PEO is an efficient flocculant for molybdenite suspensions in a wide pH range. However, similarly to polyacrylamides, the PEO flocculant also depresses molybdenite flotation. 相似文献
53.
《Journal of the European Ceramic Society》2020,40(4):1522-1531
Predicting the in-line transmittance of transparent ceramics via model calculations is a useful guide for materials design and optimization of preparation process. However, the absence of reliable input information (volume fractions and size) usually precludes the direct verification of these calculations. On the other hand, suspensions, which can be prepared with well controlled volume fractions of the solids selected, may serve as model systems that are amenable to verification. This paper describes the procedure to perform these calculations, and compares calculated data for suspensions of monodisperse spheres of amorphous silica with spectrophotometric measurements of silica monosphere suspensions with four different concentrations. Moreover, completely analogous model calculations are performed for bubbles in silica glass and pores in spinel ceramics. The results are discussed on the basis on 3D graphs, the use of which is highly recommended. The results may be considered as a benchmark for future model calculations for polydisperse systems. 相似文献
54.
《Journal of the European Ceramic Society》2020,40(12):4323-4331
Reducing the viscosity of high solid-loading ceramic suspensions and controlling the resolution of ceramic green parts produced by digital light processing (DLP) 3D printing are two important concerns in the ceramic additive manufacturing industry. The presence of ceramic particles within a photopolymerizable system leads to light scattering that reduces the resolution of the ceramic green scaffolds. This study introduced a graphite additive to solve these problems and focused on the effects of graphite concentration on the viscosity, curing behaviour and scaffold fabrication of β-TCP ceramic suspensions. As a result, it was found that an appropriate addition of graphite reduced the viscosity of the ceramic suspensions, and the light scattering decreased with the increase of graphite concentration. Both the cure depth (Cd) and excess width (Cex) also decreased with the increase of graphite concentration. But, graphite has a larger effect on the width curing than depth curing. 相似文献
55.
56.
《Ceramics International》2016,42(16):18516-18520
CeO2 nanostructures with completely different morphologies were successfully prepared using the same cerium source and mineralizer through the direct and indirect hydrothermal methods with different introducing strategies of PVP surfactant. The CeO2 nanostructures tend to form the morphologies of nano-flowers and nano-cubes through the indirect and direct hydrothermal methods, respectively. X-ray diffraction (XRD) analyses revealed that both as-prepared nanostructures are composed of CeO2 with a standard fluorite structure. The different synthesis mechanisms and corresponding chemical evolutions of the as-prepared CeO2 nanostructures are discussed based on the different introducing strategies of PVP surfactant in the direct and indirect hydrothermal processes. Investigation of the UV-shielding ability of both CeO2 nanostructures suggested that the UV absorbance of the nano-flowers is much higher than that of the nano-cubes. 相似文献
57.
《Ceramics International》2016,42(3):4556-4561
Eu-doped Ca-α-SiAlON phosphors, featuring high phase purity, uniform particle size of 3–5 μm and good luminescent properties with a yellow emission spectrum under blue light excitation, were prepared by a highly efficient combustion synthesis (CS) method. A certain amount of NaCl was applied as an innovative additive to regulate and control the properties of synthesized phosphors. Further, the effects of NaCl additive in the CS system were systematically investigated and rational proposed. It was found that the effect on accelerating nitridation and crystallization played a dominant role in the reaction as the content of NaCl was less than 6 wt%, while the effect of absorbing reaction heat through vaporization was dominant with the further-increased content of NaCl. The intensity of the emission spectrum for the sample doped with 6 wt% of NaCl was remarkably enhanced, nearly 40% more than the sample which was not NaCl-doped. Moreover, a continuous blue-shift phenomenon in emission spectra was observed with the increased content of NaCl. 相似文献
58.
This paper aims at introducing the governing equation of motion of a continuous fractionally damped system under generic input loads, no matter the order of the fractional derivative. Moreover, particularizing the excitation as a random noise, the evaluation of the power spectral density performed in frequency domain highlights relevant features of such a system.Numerical results have been carried out considering a cantilever beam under stochastic loads. The influence of the fractional derivative order on the power spectral density response has been investigated, underscoring the damping effect in reducing the power spectral density amplitude for higher values of the fractional derivative order. Finally, the fractional derivative term introduces in the system dynamics both effective damping and effective stiffness frequency dependent terms. 相似文献
59.
Zhang Xiaosong Tan Yu-an Zhang Changyou Xue Yuan Li Yuanzhang Zheng Jun 《Multimedia Tools and Applications》2018,77(9):11137-11157
Multimedia Tools and Applications - Android devices is emerging as a significant force for multimedia big data, which hold an enormous amount of information about the users. The security and... 相似文献
60.
《Measurement》2016
To predict fatigue life of Polyethylene Terephthalate (PET) modified asphalt mixture, various soft computing methods such as Genetic Programming (GP), Artificial Neural Network (ANN), and Fuzzy Logic-based methods have been employed. In this study, an application of Support Vector Machine Firefly Algorithm (SVM-FFA) is implemented to predict fatigue life of PET modified asphalt mixture. The inputs are PET percentages, stress levels and environmental temperatures. The performance of proposed method is validated against observed experiment data. The results of the prediction using SVM-FFA are then compared to those of applying ANN and GP approach and it is concluded that SVM-FFA leads to more accurate results when compared to observed experiment data. 相似文献