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151.
超临界CO2对钢材的腐蚀实验研究 总被引:3,自引:0,他引:3
采用静态高温高压釜及SEM现代分析测试手段,在分析超临界CO2存在形式及与原油、水交互作用的基础上,进行了超临界CO2对钢材的腐蚀实验研究。结果表明,在腐蚀系统SCF-CO2气相中,存在CO2腐蚀现象;液相中,腐蚀速率随压力增加而上升,12MPa达到峰值后下降。在纯水中12MPa时,液相和气相中的腐蚀速率趋于一致,腐蚀形貌表现为腐蚀瘤。30%的原油含量可在液相促进钢材腐蚀。腐蚀形貌表现为腐蚀瘤与腐蚀坑并存;但随含油量增加,会抑制钢材腐蚀。 相似文献
152.
Phosphogypsum (PG) is a solid waste produced in the wet process of producing phosphoric acid.Lignite is a kind of promising chemical raw material.However,the high sulfur of lignite limits the utilization of lig-nite as a resource.Based on fluidized bed experiments,the optimal reaction conditions for the production syngas by lignite chemical looping gasification (CLG) with PG as oxygen carrier were studied.The study found that the optimal reaction temperature should not exceed 1123 K;the mole ratio of water vapor to lignite should be about 0.2;the mole ratio of PG oxygen carrier to lignite should be about 0.6.Meanwhile,commercial software Comsol was used to establish a fuel reaction kinetics model.Through computational fluid dynamics (CFD) numerical simulation,the process of reaction in fluidized bed were well captured.The model was based on a two-fluid model and coupled mass transfer,heat transfer and chemical reac-tions.This study showed that the fluidized bed presents a flow structure in which gas and solid coexist.There was a high temperature zone in the middle and lower parts of the fluidized bed.It could be seen from the results of the flow field simulated that the fluidized bed was beneficial to the progress of the gasification reaction. 相似文献
153.
Romina Combi Maria Salsone Chiara Villa Luigi Ferini-Strambi 《International journal of molecular sciences》2021,22(8)
Dementia with Lewy bodies (DLB) is one of the most common causes of dementia and belongs to the group of α-synucleinopathies. Due to its clinical overlap with other neurodegenerative disorders and its high clinical heterogeneity, the clinical differential diagnosis of DLB from other similar disorders is often difficult and it is frequently underdiagnosed. Moreover, its genetic etiology has been studied only recently due to the unavailability of large cohorts with a certain diagnosis and shows genetic heterogeneity with a rare contribution of pathogenic mutations and relatively common risk factors. The rapid increase in the reported cases of DLB highlights the need for an easy, efficient and accurate diagnosis of the disease in its initial stages in order to halt or delay the progression. The currently used diagnostic methods proposed by the International DLB consortium rely on a list of criteria that comprises both clinical observations and the use of biomarkers. Herein, we summarize the up-to-now reported knowledge on the genetic architecture of DLB and discuss the use of prodromal biomarkers as well as recent promising candidates from alternative body fluids and new imaging techniques. 相似文献
154.
赣西地区浒坑钨矿是我国华南钨、锡、铜多金属成矿区与中生代岩浆活动密切相关的典型矿床之一。对浒坑钨矿床中与成矿有关的白云母花岗岩开展了锆石U-Pb定年、磷灰石和锆石原位微量元素研究,结果表明:赋矿白云母花岗岩的成岩时代为(152.3±1.73)Ma;磷灰石具有特殊的“M”型REE球粒陨石标准化配分模式,富F和Mn,贫Cl和Mg;锆石具有高Th/U比值,REE球粒陨石标准化配分模式亏损LREE、富集HREE。锆石微量元素(Ce、U和Ti)温度计和氧逸度计结果表明,锆石形成于岩浆早期高温(800 ℃)和低氧逸度条件下。研究认为,浒坑赋矿花岗岩在演化初期经历了强烈的矿物结晶分异,矿床的形成可能与还原性高分异岩浆演化相关。 相似文献
155.
用动电位伏安法,动电位光电流测量,表面膜的阴极还原和XRD分析等手段研究了铜在含或不含人血清白蛋白的模拟宫腔液(pH=7)中的电化学和光电化学行为,在不含白蛋白的模拟宫腔液中,铜电极表面生成的Cu2O呈n型光响应;一定量白蛋白存在时使Cu2O的光响应从n型转为p型,Cu2O在模拟宫腔液中呈n型光响应可归因于氯离子对Cu2O的掺杂,白蛋白排斥氯离子对Cu2O的掺杂,使其光响应从n型转为p型。 相似文献
156.
凝固过程中的颗粒推斥 总被引:8,自引:1,他引:8
颗粒推斥是材料在固液相变过程中的基础问题之一,界面自由能的传统理论难以解释在金属基复合材料制备过程中的颗粒推斥现象,作者提出了固液界面前沿的流体流动是颗粒推斥的主要原因之一,并给出颗粒滚动及颗粒速度两种作用机制,推导出颗粒推斥条件判据,并以实验验证流体流动的作用机制及颗粒推斥理论判据。 相似文献
157.
158.
FCC捕钒剂的研究进展 总被引:2,自引:0,他引:2
论述了钒在催化裂化过程中的危害及危害机理,对捕钒剂的捕钒机理及实验室评价方法作了叙述,介绍了国外几种捕钒剂产品及应用效果。 相似文献
159.
Energy Aspects in Drying 总被引:1,自引:0,他引:1
T. Kudra 《Drying Technology》2004,22(5):917-932
The energy performance of a dryer and a drying process is characterized by various indices such as volumetric evaporation rate, steam consumption, unit heat consumption and energy (thermal) efficiency. Of all indices, energy efficiency is the most frequently quoted, in technical specifications. A thorough analysis of available information, including the Handbook of Industrial Drying, points to the inconsistency of terminology, definition and data interpretation. Thus, reported data on energy efficiency vary significantly and frequently contradict both drying theory and industrial practice. To establish a common platform to deal with energy issues, this article provides a concise overview of the most common definitions of energy efficiency, along with a critical review of the published data. A need for energy audit and benchmarking is pointed out. To eliminate shortcomings of the energy efficiency as a lumped parameter, and to allow analysis of energy consumption over time (batch drying) or distance (continuous drying), instantaneous and cumulative indices are proposed. Using these indices, the energy performance of selected dryers is examined, and possible modifications to dryer design and operating parameters are indicated in order to reduce the overall energy consumption. 相似文献
160.