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The existence and release of fluid inclusions in bornite and its associated minerals, namely, quartz and calcite were investigated and confirmed. The structures, forms, and phases of these large quantities of fluid inclusions were also studied. A mass of fluid inclusions with various sizes, distributions, shapes, and phases exist in bornite and its associated minerals. Their sizes vary from a few micrometers to tens of micrometers, and the forms appear as negative crystals, or elongated, elliptical, and irregular. At room temperature, fluid inclusions were mainly characterized as gas-liquid two- phase. However, small amounts of fluid inclusions with pure gas phase and pure liquid single-phase were also observed in quartz and calcite. These fluid inclusions initially broke during the ore crushing and grinding process and then released into the flotation pulp in the flotation process. The quantitative analysis of fluid inclusions in the solution and the comparisons of mineral dissolution show that the amount of copper and iron released by fluid inclusions in the bornite sample is higher than the amount dissolved by the mineral; fluid inclusions in the associated gangue minerals, quartz, and calcite also make contribution.  相似文献   
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热轧带肋钢筋22MnSiV的研制   总被引:1,自引:0,他引:1  
系统的研究了热轧带肋钢筋22MnSiV各项性能,其各项性能不仅达到GB1449-1998中HRB400的要求,还有其特性,脆性转变温度低于-40℃,抗形变时效,高应变低周疲劳性能好,因此,特别适用于地震区,寒冷地区,也适用于钢筋混凝土结构。  相似文献   
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降低钢轨脱碳层深度的研究   总被引:2,自引:0,他引:2  
通过分析加热炉钢坯加热时间,加热温度和炉内气氛等工艺参数对钢轨脱碳层深度的影响,制定了降低钢轨脱碳层深度的技术措施,经现场实施应用,钢轨脱碳层深度保持在0.2-0.5mm的范围内,满足了钢轨对脱碳层浓度≤0.5mm的要求。  相似文献   
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In recent years, a new and promising polymer processing technology known as water‐assisted injection molding (WAIM) has attracted attention not only for academic reasons but also for its industrial applications. WAIM technology provides a new way to fabricate hollow or other complicated products due to its faster cycling time and light weight. This paper aims to give an overview of the basic principles and applications of WAIM as well as the current research status in academia. The origin and development of WAIM technology are first described and then, their advantages and applications are given. This review focuses on the experimental trends of WAIM such as computer simulation, the effect of processing parameters on the WAIM samples, and the morphology as well as related WAIM–molded composites and polymer blends' work.  相似文献   
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This paper deals with the issue of preparation of the aiming angles with the use of tabular firing tables and needed determination of the ballistic elements μB (ballistic wind wB Wxm WzB, ballistic (virtual) temperature τB, ballistic density ρB) from the standardized met messages. The weighting factors are used for the calculation of ballistic elementsμB that are incorporated into the trajectory calculations characteristics of weapon and ammunition. Two different methodologies practically used in the praxis are analysed and compared. For the comparison of the two methodologies the reference height of trajectory determined from the weighting factor functions is employed. On the basis of the analyses conducted, the potential for further increase in accuracy of these aiming angles preparation methods is pointed out.  相似文献   
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The experimental investigations of the effect of contact time/temperature on initiating the cook-off using 7.62 mm calibre cartridge cases (CC) were conducted previously. These cartridges were filled with commercial off-the-shelf (COTS) double based (DB) propellant (Bulls Eye) and were loaded in a hot chamber. The thermal explosion temperature is of great significance to both weapon designers and safety inspectors as it provides the operational limit and safe operating temperature. For CC under test, it was found that the cook-off temperatures of this propellant were encountered with the heat transfer profile of the simulated gun barrel between 151.4 ℃ and 153.4 ℃, with a reaction occurring in less than 300 s after the round was chambered. Usefully, each experiment was found to be consistent and repeatable.  相似文献   
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研究介绍了圆形孔径的球面聚焦压电换能器的基本电声参数:输出声功率、辐射电导、电声效率、自由场发射电流(电压)响应、自由场电压灵敏度、有效面积、有效孔径、声焦距、声束宽度和阻抗(导纳)等电声特性及其测量方法,详细地论述了基于辐射力天平法和自易校准法的测量原理和方法,讨论了它们的内在联系。给出了换能器自易校准中的衍射修正系数和平均反射系数的公式、计算方法和系列数据图表。试验结果表明了测量原理和方法的合理性和可行性。  相似文献   
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