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31.
孙孝仁 《砖瓦》2021,(2):26-26
介绍了一种由梯形砖改型设计而成的新型多功能燕尾空心卯砖及其实际应用。  相似文献   
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通过矿相显微镜、扫描电镜、电子探针、X射线能谱元素面分析等多种手段综合研究了川北某黑色页岩型铼矿中铼的赋存状态。样品为黑色页岩,有机碳含量较高。粘土矿物总量为14.6%,黄铁矿含量16.2%,石英含量37.7%。样品具典型的粘土结构,矿物粒度微细。铼有两种赋存状态,一种呈类质同象形式赋存于黄铁矿内,另一种则以分散形式存在。典型黄铁矿测点Re平均含量为0.024%。黄铁矿是Re的重要载体矿物。建议通过浮选分离黄铁矿,从而实现Re的富集。   相似文献   
34.
陈平  田宇  胡成 《无机盐工业》2020,52(10):130-134
为了解决脱硫石膏的大量堆存对环境造成的潜在危害,同时提高脱硫石膏的附加值,采用常压盐溶液水热法以电厂脱硫石膏为原料探究α-半水石膏的最佳合成工艺,重点研究了盐溶液种类及浓度对α-半水石膏的合成过程、合成产物组成及结构的影响。结果表明:在氯化钙、氯化镁盐溶液中,由于同离子效应和硫酸镁离子对的形成,导致半水石膏的形成过程受阻。较高浓度氯化钾和氯化钠盐溶液可使二水石膏发生转晶,其中氯化钾会致使半水石膏过度脱水生成无水钾石膏,氯化钠盐溶液可以使二水石膏转变为半水石膏并维持较长时间,通过比较得出最佳合成工艺为氯化钠溶液质量分数为15%、体系反应温度为95 ℃、固液质量比为1∶4、搅拌速率为150 r/min、合成时间为3 h,可以制得长径比约为5∶1的六方短柱状α-半水石膏。  相似文献   
35.
This study proposes a method of constructing type II generalized angulated elements (GAEs II) Hoberman sphere mechanisms on the basis of deployment axes that intersect at one point. First, the constraint conditions for inserting n GAEs II into n deployment axes to form a loop are given. The angle constraint conditions of the deployment axes are obtained through a series of linear equations. Second, the connection conditions of two GAEs II loops that share a common deployable center are discussed. Third, a flowchart of constructing the generalized Hoberman sphere mechanism on the basis of deployment axes is provided. Finally, four generalized Hoberman sphere mechanisms based on a fully enclosed regular hexahedron, arithmetic sequence axes, orthonormal arithmetic sequence axes, and spiral-like axes are constructed in accordance with the given arrangement of deployment axes that satisfy the constraint conditions to verify the feasibility of the proposed method.  相似文献   
36.
Type 2 diabetes mellitus patients are at significant risk of cardiovascular disease, however, the pathophysiology of these complications is complex and incompletely known in this population. The aim of this study was to compare the serum proteome of patients with type 2 diabetes mellitus presenting or not presenting cardiovascular disease with non-diabetic subjects to find essential proteins related to these cardiovascular complications. This cross-sectional study compares the serum proteome by a combination of protein depletion with 2D-DIGE (2-dimension Difference Gel Electrophoresis) methodology. The proteins differentially expressed were identified by MALDI TOF/TOF (Matrix-assisted laser desorption/ionization and Time-Of-Flight ion detector) or LC-MS/MS (Liquid Chromatography coupled to Mass-Mass Spectrometry). Type 2 diabetes mellitus patients with cardiovascular disease showed higher expression of plasma retinol binding protein and glutathione peroxidase-3 compared to those without cardiovascular disease and non-diabetic controls. These results show that proteins related to the inflammatory and redox state appear to play an important role in the pathogenesis of the cardiovascular disease in the type 2 diabetes mellitus patients.  相似文献   
37.
以韶州府学宫大成殿为例,着重从建筑沿革、建筑型制及尺度分析入手,探讨粤北地区殿堂建筑设计的原则,并指出大成殿构架中上层檐柱支撑方式的独特性,以及建筑构造上在檐下采用粤北地区较常见的朵式插栱,总结粤北地区传统建筑的地方性特征。  相似文献   
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39.
The surface roughness of barium titanate (BTO) following its implication by aerosol deposition method (ADM), is a very important characteristic affecting its potential for use in high-k metal-insulator-metal capacitors. The ADM is the best candidate to deposit ceramic films but has two major problems: macroscopic defects and rough interface effects on the BTO surface. In this work, a chemical mechanical polishing (CMP) technique is applied to obtain an ultra-smooth BTO surface morphology by the optimization of several factors including the slurry type, the head rotational speed, and the down pressure. Statistically, we were able to achieve a root mean square (RMS) value of the BTO surface of 1.746 nm by utilizing a two-step polishing process, applied at a head rotational speed of 70 rpm under 5 kg/cm2 of down pressure; this RMS value is improved at least 8 times over previous studies. This analysis is based on representative pattern images, three-dimensional images, line profiles, histograms, and power spectra of selected BTO surface areas, further verified with data from both energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy.  相似文献   
40.
This paper deals with the investigation of the effect of hygrothermal conditions on the bending of nanoplates using Levy type solution model employing the state-space concept. The nanoplates are assumed to be subjected to a hygrothermal environment. The two-unknown function plate theory is used to derive the governing differential equations on the basis of Eringen's nonlocal elasticity theory. The governing equations contain the small scale effect as well as hygrothermal and mechanical effects. These equations are converted into a set of first-order linear ordinary differential equations with constant coefficients. Analytical solution of bending response for nanoplates under combinations of simply supported, clamped and free boundary conditions is obtained. Comparison of the results with those being in the open literature is made. The influences played by small scale parameter, temperature rise, the degree of moisture concentration, boundary conditions, plate aspect ratio and side-to-thickness ratio are studied.  相似文献   
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