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1.
用高能球磨制备等原子比铁(Fe)钴(Co)镍(Ni)铁镍钴复合粉体,用激光熔覆方法制备复合粉铁镍钴体合金涂层。用OM、HV、XRD、SEM、EDS、SVET等对复合粉体及熔覆合金层进行了组织表征及性能测试。结果表明,复合粉体经3 h高能球磨后均匀细化,平均尺寸从35μm到15μm左右,镍晶格有一定畸变,有新相Co3Fe7产生;用优化后的激光熔覆工艺激光功率2 000 W,激光扫描速度10 mm/s,保护Ar气流速度12 L/min制备中熵熔覆合金Fe Co Ni涂层;XRD、SEM、EDS表明熔覆层合金是单一的面心立方(FCC)相,Fe, Co, Ni成分均匀分布,没有金属间化合物产生;熔覆层的HV约是243,在0.5 mol/L氯化钠溶液中熔覆层的SVET表明耐腐蚀性能好。  相似文献   

2.
INTRODUCTION The solid oxide fuel cell (SOFC) has attracted much attention as a promising source of electrical power generation because of its high efficiency in converting chemical energy to electrical power. De- velopment of SOFC with operating temperature of less than 800 °C has been extensively studied. SOFC has the potential to have the cost of its materials, cell fabrication, and corrosion of its stack components dramatically reduced. Gadolinia-doped ceria with the chemical fo…  相似文献   

3.
The effect of non-reactive powder particle properties on the detergent dry agglomeration process in a high shear mixer was investigated. Three types of micron-scale silica were chosen as the non-reactive fine powders and a semi-solid alkyl ethyl ethoxy sulfate(AES) paste with ultra-high viscosity was chosen as the binder. The granules were characterized using massbased granule size distribution, scanning electron microcopy, and bulk density tests. The results revealed that powder particle size plays a leading role in agglomeration behavior. A decrease in the median particle size results in enhanced dispersion of silica particles in the AES paste binder droplets, which leads to the formation of uniform granules that are slightly affected by compacting forces. Agglomerate quality, using silica with high oil absorption as well as optimum particle size, was satisfactory, and the product exhibited a smaller median particle size, narrower size distribution, and superior anti-caking capacity under the same liquid-to-solid ratio(L/S).  相似文献   

4.
超细氧化镁的制备   总被引:1,自引:0,他引:1  
以工业硫酸镁和草酸铵为原料,采用直接沉淀法合成了超细粉体氧化镁,并通过红外光谱(IR)、热重分析(TG-DTA)、X射线粉末衍射(XRD)、透射电镜(TEM)等手段对该纳米微粒的结构进行了表征.结果表明所制得的纳米氧化镁微粒呈立方晶格,形貌为椭球体,分散性好,粒径在25~35nm之间.考察了反应物浓度、加料方式和煅烧温度等各种因素对粉体质量的影响.  相似文献   

5.
雷公藤巴布剂能明显抑制巴豆油诱发的小鼠耳廓炎症;能显著抑制小鼠腹腔巨噬细胞的吞噬功能;降低小鼠碳粒廓清指数;能抑制T淋巴细胞百分比(外周血T淋巴细胞酶标记染色法)。皮肤刺激及皮肤过敏试验表明,一次及多次给药后各观察时间均未发生刺激反应,亦未发生全身过敏反应。结论:雷公藤巴布剂具有明显的抗炎和免疫抑制作用。无皮肤刺激性和过敏反应。  相似文献   

6.
采用溶胶凝胶法制备掺铝氧化锌粉末,通过控制铝盐的添加量来制备不同掺杂比例的掺铝氧化锌粉末,使用XRD来测试铝是否掺杂在氧化锌的晶格中,利用SEM来反映掺铝氧化锌粉末的外观以及颗粒分布聚集情况,用激光粒度分布仪来测其颗粒大小。并用所制备的氧化锌粉末样品对甲基红和溴甲酚绿进行光催化,使其降解,通过观察降解的效果,选择最佳的掺杂比例。结果表明,铝元素是掺杂在晶体中,且掺铝摩尔比为5%,煅烧温度为500℃,煅烧时间为3 h,其降解甲基红、溴甲酚绿效率最高。  相似文献   

7.
目的:探讨糖尿病性脂肪肝胰岛素强化治疗的方法、效果,临床病理变化。方法:将42例糖尿病性脂肪肝患者分为A、B两组,分别采用静点胰岛素、皮下注射胰岛素强化治疗,肝穿刺活检检查肝组织病理变化。结果:两者间不同时相血糖及血浆胰岛素浓度有显著性差异(P<0.05);肿大肝脏恢复正常大小时间的差异有显著性(P<0.01);肝穿活检证实代谢紊乱纠正后脂肪肝可以逆转。结论:提示静点胰岛素强化治疗糖尿病性脂肪肝优于皮下注射胰岛素强化治疗。  相似文献   

8.
Insulin is a major protein hormone secreted by the β-cells of the pancreas and is important for the control of diabetes. Insulin is usually administered to diabetic patients through subcutaneous injection. This mode of therapy has certain inherent disadvantages such as local pain, itching and insulin lipodystrophy around the injection site. Hence, pharmaceutical scientists have been trying to design an oral delivery system for insulin. Many challenges are associated with the oral delivery of insulin, relating to the physical and chemical stability of the hormone, and its absorption and metabolism in the human body. Here we discuss various strategies for the oral delivery of insulin that are being tried out, as well as methods used to improve the absorption of orally consumed insulin and to reduce its degradation by digestive enzymes. K Gowthamarajan is on the faculty of the Department of Pharmaceutics in JSS College of Pharmacy, Ootacamund. His research interests are in the area of designing drug delivery systems for peptides and proteins. He is currently involved in research on pharmaceutical applications of plant polysaccharides. Giriraj T Kulkarni is on the faculty of the Department of Pharmaceutics in JSS College of Pharmacy, Ootacamund. Currently, he is involved in research on pharmaceutical and biotechnological applications of plant polysaccharides. He has authored a book ‘Biotechnology and its Applications in Pharmacy’ for undergraduate and postgraduate students of pharmacy.  相似文献   

9.
研究利用Visual Basic6.0和SQL Server2000开发物流送货管理系统的方法.该系统包括订货、送货和报表管理,使接受订货和发出订货更为省力,防止订货和送货出现差错,提高了工作效率.  相似文献   

10.
研究香菇多糖冻干粉针剂的处方及制备工艺,并对其进行质量评价.经预实验选定复合赋形剂及配比,实验考察其用量对制剂成型性的影响,用正交法筛选最优处方,以冷冻干燥法制备粉针剂,并测定其有关质量指标.通过筛选的优化处方为:香菇多糖50mg,赋形剂L-精氨酸300mg和甘露醇250mg,加水量为75mL,溶液PH值为7.0-7.5;制备的冻干粉针剂质量优良、综合评定其分值为5.处方合理,制备工艺可行,检验结果准确可靠.  相似文献   

11.
通过溶胶凝胶法制备NixZn1-xFe2O4(x=0.2,0.4,0.6,0.8)铁氧体粉体.XRD显示制备的样品具有良好的尖晶石结构.研究了其磁性能比如密度、起始磁导率、Q值和截止频率.  相似文献   

12.
在1,2丙二醇-水体系中,以PdCl2为成核剂,NiSO.46H2O和无水Na2CO3反应生成的NiCO.32N(iOH).22H2O前驱体,回流2.5 h后,加入还原剂水合肼,反应30 min后制得纳米镍,其分散好.所制备的纳米镍粉用X射线衍射分析法、透射电镜进行了表征,发现前躯体在1,2丙二醇-水体系中回流反应,有利于最终产物提高分散度.  相似文献   

13.
采用溶胶-凝胶法制备了不同掺杂浓度的Mn-Al共掺杂Zn O粉末。用XRD分析了粉末的晶格结构。表明所有样品都具有纤锌矿结构。当Mn(1wt%)掺入纯Zn O时晶格常数明显变大,这表明Mn已经进入了Zn O晶格,且Mn离子处于正二价态。随着粉末中Al浓度的增加,发现晶胞参数a,c开始略有减小,而后随Al离子浓度增大而变大。确定了在Mn(1wt%)掺杂的前提下,Al对Zn O掺杂的最佳浓度为2wt%。  相似文献   

14.
荧光增白剂在无磷洗衣粉中效能讨论   总被引:1,自引:0,他引:1  
以常用表面活性剂LAS、AEO—9和助剂结晶型层状硅酸钠、4A沸石、荧光增白剂VBL、31配成实验用无磷洗衣粉。通过粉体白度实验,去污实验和循环洗涤实验,考察了荣光增白剂在洗衣粉中的效能.实验结果表明:添加荧光增白剂使物体白度提高;去污力比值提高,荧光增白剂VBL、31在农洗衣粉中的最佳添加量其质量分数是0.15%。  相似文献   

15.
用柠檬酸络合法制备了尖晶石型复合氧化物SrAl2O4、BaAl2O4,用XRD、TEM等手段对催化剂结构和性能进行了表征,并考察了其在可见光下降解刚果红的催化性能。结果表明,在可见光条件下,60 min内BaAl2O4使刚果红降解率达80%以上,SrAl2O4降解率大约为70%。SrAl2O4的催化活性低于BaAl2O4可能是由于电子层结构的不同造成的。  相似文献   

16.
Food-deprived rats develop polydipsia on an intermittent schedule (fixed time 60 sec) of food pellet delivery, but not on an identical schedule of food powder delivery. This result was demonstrated with separate groups receiving each type of food and was replicated using rats as their own controls. Powdered food not only prevented the development of polydipsia, but it abruptly terminated ongoing polydipsia in rats that were switched from the scheduled delivery of pellets to powder. Ethological analysis of the behavior showed that the rats receiving powder were not engaging excessively in some behavior other than drinking. After discounting several factors, we concluded that the amount of oral activity associated with feeding, which occurred immediately after food delivery, was reciprocally related to the level of drinking.  相似文献   

17.
用柠檬酸络合法制备了尖晶石型复合氧化物SrAl2O4、BaAl2O4,用XRD、TEM等手段对催化剂结构和性能进行了表征,并考察了其在可见光下降解刚果红的催化性能。结果表明,在可见光条件下,60 min内BaAl2O4使刚果红降解率达80%以上,SrAl2O4降解率大约为70%。SrAl2O4的催化活性低于BaAl2O4可能是由于电子层结构的不同造成的。  相似文献   

18.
提出一种应用于智能胰岛素笔的步进电机驱动控制优化方案。具体实现过程中,采用TI公司的MSP430微处理器作为主控芯片,配合Allegro公司的电动机驱动器A3901芯片,并结合IAR Embedded Workbench for MSP430v5.10系统环境,采用梯形线圈电流波形的微步模式,实现对两相步进电机的驱动控制。同时,出于用户注射安全的考虑,通过加入光电检测装置,可以实时监测电机运行状态。结果表明:该设计能有效地提高注射过程的精确性、舒适性和安全性,更有利于糖尿病患者的使用。  相似文献   

19.
Mechanical and physical properties, such as tensile strength, elongation at break, modulus of elasticity, Shore D hardness, melt flow rate (MFR), and electrical and thermal conductivities of composites with high density polyethylene matrix reinforced with Al powders were investigated experimentally. Measurements of the mechanical and physical properties were performed up to a reinforcing component concentration of 30% volume Al powder and compared with mathematical models from the literature. The obtained results have shown that experimental data were in good agreement with theoretical data. The ultimate tensile strength (UTS) and elongation at break decreased with increasing Al powder content, which was attributed to the introduction of discontinuities in the polymer structure, and modulus of elasticity increased with increasing Al content. The composite preparation conditions allowed the formation of a random distribution of metallic particles in the polymer matrix volume for system high density polyethylene-Al (HDPE-Al). There was a cluster formation of Al particles at higher Al contents in the polymer matrix. Electrical and thermal conductivity values of HDPE-Al composites were higher than pure HDPE values.  相似文献   

20.
TiC增强涂层以钛铁粉、铁粉、铬粉和碳的前驱体(蔗糖)等为原料,通过前驱体碳化复合技术制备了Fe-Cr-Ti-C等离子熔覆复合粉末,并通过等离子熔覆技术在Q235钢表面成功原位合成.采用SEM、XRD和EDS对涂层的相组成和显微组织结构进行了分析,并在室温干滑动磨损条件下测试了该涂层的耐磨性能.结果表明,等离子熔覆涂层由原位合成的TiC相和(Cr,Fe)7C3共晶相与奥氏体相构成,与基材完全冶金结合.涂层中碳化物TiC呈现梯度分布,并且涂层的熔合区和中部区域TiC颗粒形状大多呈现粒状,涂层的表层区域部分TiC颗粒呈现树枝状.涂层的硬度从表面到熔合区相差不大,平均显微硬度约是HV02750,是基体金属的3.2倍.涂层磨损质量约是基体金属的1/12,具有良好的耐磨性能.  相似文献   

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