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91.
分别以碳酸盐和硝酸盐为前驱体,采用熔盐法在750~1050℃合成了针状的Sr0.5Ba0.5Nb2O6(SBN50)模板晶粒。通过XRD,SEM分析方法,研究了前驱体对SBN50晶粒相结构和微观形貌的影响,并讨论了其形成机理。结果表明:前驱体性质的不同造成熔盐熔点时SrNb2O6数量和形貌的差异,影响最终SBN50晶粒的形貌;SBN50晶粒的生长是二维成核过程。  相似文献   
92.
采用共沉淀–熔盐法制备了M型铁氧体BaFe11.85-2xCoxTixMn0.15O19。运用TGA-DTA、XRD、SEM和矢量网络分析仪,对样品的晶化过程、相组成、显微形貌及微波吸收性能进行了表征。结果表明:Co2+、Ti4+固溶到铁氧体的晶格并取代Fe3+位,有助于提高铁氧体的电、磁损耗。当取代量x为1.2时,微波吸收最强,制得的样品的吸波频率在8.2~12.4 GHz范围内,tanδe、tanδμ的最大值分别为:9.0,6.8。  相似文献   
93.
以BH—G/K玻璃为基体,以添加Al2O3粉的DM—308玻璃为表层区研制出与金属外壳封接的双层玻坯。分析了Al2O3粒度及添加量对熟坯致密化和线收缩率的影响。结果表明,表层区使用添加质量分数为20%和30%0.5μm粒径Al2O3粉的DM—308玻璃可以实现熟坯的匹配收缩,用于UP2113—14外壳熔封。电镀后外壳气密性、绝缘电阻均有数量级提高,玻璃沿引线上爬高度只为BH—G/K玻璃的1/3,显著降低外壳盐雾试验后引线根部易锈蚀和引线受力后绝缘子开裂的风险。  相似文献   
94.
Membrane decorated with biocides is an effective way to suppress biofilm growth. However, their immediate biocidal effect usually suffers from a significant decline due to the irreversible consumption of the biocides. Here, a smart nanofiltration membrane is reported with rechargeable antibacterial capability that is fabricated by a facile interfacial polymerization via 3-aminophenylboronic acid and trimesoyl chloride on a polysulfone substrate. Biocides bearing diol groups can be grafted onto the membrane surface under neutral/alkaline condition and then released from the surface under acidic environment, due to the pH-responsive feature of boronate ester complexes. The resultant membrane exhibits integrated properties of fast bacterial inactivating efficiency, rechargeable antibacterial capability, and impressive stability. In addition, the achieved membrane shows remarkable separation efficiency to dye/monovalent salt system. The successful fabrication of the membrane with rechargeable anti-bacterial property provides new insights into the development of pH-responsive and sustainable antibacterial membranes.  相似文献   
95.
Mg batteries as the most typical multivalent batteries are attracting increasing attention because of resource abundance, high volumetric energy density, and smooth plating/stripping of Mg anodes. However, current limitations for the progress of Mg batteries come from the lack of high voltage electrolytes and fast Mg‐insertable structure prototypes. In order to improve their energy or power density, hybrid systems combining Li‐driven cathode reaction with Mg anode process appear to be a potential solution by bypassing the aforementioned limitations. Here, FeS x (x = 1 or 2) is employed as conversion cathode with 2–4 electron transfers to achieve a maximum energy density close to 400 Wh kg?1, which is comparable with that of Li‐ion batteries but without serious dendrite growth and polysulphide dissolution. In situ formation of solid electrolyte interfaces on both sulfide and Mg electrodes is likely responsible for long‐life cycling and suppression of S‐species passivation at Mg anodes. Without any decoration on the cathode, electrolyte additive, or anode protection, a reversible capacity of more than 200 mAh g?1 is still preserved for Mg/FeS2 after 200 cycles.  相似文献   
96.
高氯酸铵的热分解   总被引:26,自引:12,他引:26  
用差热分析及其在FTIR联用技术研究了两种粒度高氯酸铵(AP)的热分解过程,提出了AP晶体分解的“局部化学”现象,通过FTIR实时跟踪检测气体产物,并结合文献报道,提出了AP两个阶段分解的不同机理。  相似文献   
97.
硝酸铵防吸湿性和防结块性研究   总被引:1,自引:1,他引:1  
用十二烷基苯磺酸铈(CDBS)、硬脂酸铈(CSA)和十八烷胺硝酸盐(ON)等添加剂包覆硝酸铵(AN)以防其吸湿和结块,分析了添加剂降低AN吸湿性和结块性的原因。结果表明,与纯AN相比,添加CDBS、CSA和ON的AN的结块性和吸湿性明显降低,CDBS、CSA和ON组成的复合添加剂对AN的防潮、抗结块效果优于单一添加剂。液相包覆处理法优于机械混合法。包覆温度和复合添加剂的添加次序是影响抗结块效果的两个主要因素。  相似文献   
98.
The glaciogenic Al Khlata Formation (Late Carboniferous – Early Permian) contains important reservoir and seal intervals in oil fields in southern Oman. Here we describe a 3D regional geological model of the Al Khlata Formation and the underlying Misfar Group in a 1750 km2 area in the Eastern Flank of the South Oman Salt Basin. The Misfar Group (Devonian‐Carboniferous?) was included in the model because it also contains glaciogenic facies in the study area. The 3D model is based on wireline logs from 42 wells, palynological zonation in 31 wells, cores from three wells, and a 2011 3D seismic dataset from which three horizons (top‐Huqf, top‐Rahab Shale and top‐Gharif) were interpreted throughout the study area. The combined Al Khlata and Misfar interval varies in thickness in the area from 20 to 730 m over relatively short distances. These large variations in thickness were due to the creation of accommodation in mini‐basins resulting from the removal of underlying Infracambrian salt at the basin margin. In places, some of the available accommodation was occupied by Cambrian sandstones of the Nimr Group and Haima Supergroup, influencing the location and thickness of the Al Khlata mini‐basins. These local depocentres vary in scale, shape and orientation relative to the present‐day salt edge: some are ovoid in plan‐view, others more linear and parallel to the salt edge, and one takes the form of a narrow graben almost perpendicular to the salt edge. By the Early Permian, towards the end of Al Khlata time, deposits become more blanket‐like and uniform, indicating an external or more regional control on base level. Four key lithofacies have been distinguished from wireline logs and were populated zone‐by‐zone through the geological model: sandstone (reservoir), shale (seal), and sandy and silty diamictite. Sandstones are most common towards the base of the Misfar – Al Khlata interval and shales towards the top. The Rahab Shale (Early Permian) at the top of the Al Khlata Formation forms an important seal for oil fields in South Oman, often in combination with seals in overlying intervals. The Rahab Shale was the first widespread seal to be deposited which may have trapped oil migrating from the South Oman Salt Basin during the Palaeozoic. The most common lithofacies in the Misfar – Al Khlata interval in the modelled area is diamictite (60%), which is normally considered to be a waste‐rock lithology. However thick silty diamictites of sufficient extent can seal hydrocarbon accumulations, and some sandy diamictites have the potential to be unconventional reservoir rocks. Even after 50 years of exploration and production of oil from the Al Khlata Formation, there remains potential for further discoveries and overlooked pay zones due to its heterogeneous character and the occurrence of intra‐formational seals.  相似文献   
99.
盐构造是由于岩盐和其他蒸发岩的流动形变所形成的地质体。世界上大约有60%的含油气圈闭与盐构造有关。在地震和探井资料基础上,以渤海湾盆地济阳坳陷东营凹陷中央隆起带-盐构造为切入点,探讨了该构造的物质基础和动力之源,并将其发育分成3个阶段:发育初期、发展期和稳定期。同时,分析了该盐构造发育对沉积地层的影响,指出盐构造形成后的外形与当时地质历史时期的气候有一定关系,该地区的气候在盐构造稳定后向干旱期转化,与盐构造发育有关的断层破坏了油气藏的形成,使该地区地层复杂化。盐构造的研究在国内尚不成熟,它应是今后勘探的热点之一。  相似文献   
100.
柳长春 《钻采工艺》2006,29(3):82-83
介绍一种用于聚合物驱油的新型聚合物交联体系,通过试验,对比分析了聚合物浓度、聚交比、剪切降解、温度、热稳定性等对交联体系性能的影响,表明该体系可用于高矿化度、中等温度的油藏聚合物调驱油。新型交联体系的耐盐能力高达70000mg/L(其中Ca^2++Mg^2+含量为1627.35mg/L),耐受温度达到80%,可获得较好的聚合物调驱油效果。  相似文献   
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