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1.
高品质纳米氧化锌粉体的制备及其表征   总被引:6,自引:0,他引:6  
讨论了以均匀沉淀法制备纳米ZnO的影响因素,首次提出了在反应体系中加入表面活性剂,控制溶液pH值的相对稳定性的方法。并制备了高品质纳米ZnO粉体,XRD及TEM分析表明:ZnO纳米粒子10nm-30nm,颗粒均匀,分散性好。  相似文献   

2.
制备一种适于早期HIV的大范围筛查使用的检测人唾液中抗HIV-1抗体的胶体金免疫层析试纸条.采用柠檬酸三钠还原法制备直径为19nm的胶体金颗粒,标记HIV-1gp41抗原,制备胶体金免疫复合物,按常规组装成免疫层析检测试纸条.结果表明:阳性HIV患者唾液中的抗HIV抗体与测试条上金标记物结合后沿着硝酸纤维素膜移动,与膜上的固相抗原结合形成肉眼可见的红色圆点.胶体金颗粒粒径均一,胶体金免疫复合物性能稳定,特异性强,试纸条检测时间只需10~20min.制备的胶体金免疫层析试纸条检测唾液中HIV抗体,使用安全,简便快速,结果准确,适用于基层医疗单位使用和对大量人群的规模筛查等.  相似文献   

3.
Gold nanoparticles with different shapes and sizes were prepared by adding gold precursor (HAuCl4) to an electrolyzed aqueous solution of poly(N-vinylpyrrolidone) (PVP) and KNO3, which indicates the good reducing capacity of the PVP-containing solution after being treated by electrolysis. Using a catholyte and an anolyte as the reducing agents for HAuCl4, respectively, most gold nanoparticles were spherical particles in the former case but plate-like particles in the latter case. The change in the pH value of electrolytes caused by the electrolysis of water would be the origin of the differences in shape and morphology of gold nanoparticles. A hypothesis of the H+ or OH? catalyzed PVP degradation mechanism was proposed to interpret why the pH value played a key role in determining the shape or morphology of gold nanoparticles. These experiments open up a new method for effectively controlling the shape and morphology of metal nanoparticles by using electrochemical methods.  相似文献   

4.
A two-dimensional (2D) ordered hexagonal close-packed structure, formed by 1-nonanethiol-capped gold nanoparticles, is reported. The structure was constructed only by dipping the gold nanoparticle colloidal solution on flat substrate. The gold nanoparticles were synthesized as follows: First, AuCl4-1 was transferred from aqueous solution to toluene by the phase-transfer reagent of tetraoctylammonium bromide. Then it was reduced with aqueous sodium borohydride in the presence of a given amount of 1-nonanethiol molecules which was used to control the nucleation and growth of the gold nanoparticles for the desired size. The experimental techniques, such as UV-Vis, FT-IR, and X-ray photoelectron spectroscopy (XPS), were employed to characterize the obtained product. Transmission electron microscopy (TEM) measurement demonstrated the size of the gold nanoparticle and the formation of two-dimensional ordered hexagonal close-packed gold nanoparticle structure.  相似文献   

5.
由N235与路易斯碱三辛基氧膦(TOPO)组成协同萃取体系,对碱性氰化浸金贵液中金(I)协同萃取和反萃进行了研究.研究了有机相中N235含量、水相平衡pH、相比等因素对金(I)萃取率的影响,考察了反萃液中氢氧化钠液浓度对负载金有机相的反萃效果.结果表明,采用有机相为10%+10%协萃剂TOPO+80%煤油的协萃体系,对pH=9~10和初始金(I)质量浓度ρO=10.87 mg/L碱性氰化浸金贵液进行萃取时,经一级萃取后,萃取率可高达98%左右;同时,采用0.05~0.1 mol/L的氢氧化钠溶液可对负载有机相进行反萃,反萃率达到91%以上.  相似文献   

6.
嗜热菌对高砷金精矿氧化-氰化提金试验研究   总被引:1,自引:2,他引:1  
HQ-0211嗜热菌是一种良好的浸矿菌种,具有良好的耐砷性能,适合处理高砷金精矿.采用HQ-0211嗜热菌对含砷质量分数为11.78%金精矿进行氧化6 d后,金精矿含砷质量分数下降到0.20%,液体砷质量浓度达到11.41 g/L,脱砷率达到99.24%,失重率63.38%.含砷质量分数为11.78%的金精矿经过嗜热菌的氧化预处理,金的回收率大大提高,从直接氰化的18.25%提高到92.12%.试验表明含砷11.78%金精矿的细菌氧化-氰化试验取得了很好的工艺技术指标,不需要配矿降砷,该菌氧化时间短,脱砷、脱硫效果良好.  相似文献   

7.
采用各种电化学方法对金在硫代硫酸盐溶液中阳极溶解的行为及机理进行的研究表明,无氨时,金的阳极溶解约在50mV(SCE)出现电流峰,极化曲线有明显的钝化特征,金的阳极溶解速度较慢;氨对金的阳极溶解有显著的促进作用,它使钝化作用减弱,金的溶解速度增大。金在含氨的硫代硫酸盐溶液中的溶解机理是:氨优先与金粒表面阳极上的金离子络合,生成的金氨络离子进入溶液后被硫代硫酸根离子取代,生成最终产物金硫代硫酸根离子。  相似文献   

8.
实验采用反溶剂重结晶法对硫酸沙丁胺醇进行超细化。将乙醇、异丙醇、丙酮作为反溶剂进行了对比实验,最后选定丙酮作为该体系的反溶剂,并且确定了最佳反溶剂和溶液的体积比为10∶1。结果证明,体系的过饱和度ΔC越大重结晶所得到的颗粒就越小,采用反加法、低温、高搅拌速度能够增大体系的过饱和度,得到 300nm的针状颗粒产品。  相似文献   

9.
本文采用分光光度法研究了纳米金溶液、CT-DNA及两者混合液高速离心前后的吸收值的变化情况,发现纳米金溶胶和DNA之间存在相互作用,并进一步证明了两者有定量的结合关系。  相似文献   

10.
D A Schafer  J Gelles  M P Sheetz  R Landick 《Nature》1991,352(6334):444-448
  相似文献   

11.
Two synthetic techniques for colloidal gold particles was improved by using SDS. And colloidal Au particles of mean diameters between 5 and 14 nm are synthesized, that exhibit improved monodispersity relative to previously published methods. According to the particular molecular structure of surfactants and different electrons distribution arising from colloidal small sizes and high surface/ volume ratios, it is found that there are a complex between SDS and Au3+ (and Au atoms ) during synthesizing colloidal gold nanoparticles and as a stablizer for Au particles, SDS can prevent their further growth. So the colloidal gold particles is monodispersize and more steady. But other surfactants don't affect the process of synthesizing gold nanoparticles because of their structures and properties different from SDS. Gold nanoparticles have considerable bioaffinity and can be applied to study the adsorption of proteins or polypeptides.  相似文献   

12.
高含Cu量Mo-Cu合金的液相烧结   总被引:7,自引:0,他引:7  
采用液相烧结Mo、Cu混合粉压坯的方法制取合金,分析了合金的力学性能及组织。借助TEM,SEM组织观察以及电子探针成分(EDXA)分析表明:Mo-Cu合金的烧结由于Mo的溶解-析出,Mo晶粒表面有Mo、Cu不同比例含量的过渡层,该层中组织均匀细小。在润湿角为0°附近温度烧结合金性能最佳。  相似文献   

13.
在深入研究黔东南从江地虎金银多金属矿成矿地质背景及构造特征的基础上,从构造地球化学方面对黔东南从江地虎金银多金属矿构造特征进行研究,进行了变形、破裂实验,成矿物质活化、迁移实验和压力溶解、韧性流动模拟实验,并进行宏观及微观构造对比。实验结果初步验证了地虎金银多金属矿的构造特征,为该区构造控制金矿提供了重要的实验材料,同时为研究该区的找矿提供了有益信息。  相似文献   

14.
本文讨论了在酸性溶液中,用湿法氯化从新疆托里地区氰化法矿渣中提取金的实验方法.在本文确定的实验条件下,各种试验结果表明:金的总回收率>90%以上,为新疆的氯化冶金开发利用提供了新的途径.  相似文献   

15.
针对机器人在与人交互过程中对指定人体目标的跟踪容易受到周围其他人体干扰的问题,提出了一种人机交互中的人体目标跟踪算法.将所有干扰区域看作候选目标,通过建立基于重叠率的粒子分布模型,确保粒子集可以通过均值偏移收敛到所有的候选目标,并减少粒子数量.以权重距离总误差和目标尺寸作为聚类条件,将粒子划分到相应的候选目标粒子集中,最后选择最优的候选目标作为跟踪结果.实验结果表明:该算法能够避免周围相似物体的干扰并准确跟踪目标,具有较好的鲁棒性和实时性.  相似文献   

16.
为探究矿石粒径对矿堆内溶液毛细渗流的影响特征,利用所构建的溶液毛细上升实验装置,针对单一粒径矿堆和混合粒径矿堆,分别开展不同矿石粒径下溶液毛细上升实验,得到了溶液毛细上升高度与时间的关系曲线及相应的拟合方程,分析了溶液上升速度随时间变化规律。研究发现:实验初期矿堆内溶液上升速度较快,随着实验时间的增加,溶液上升速度逐渐减小并最终降为零,且溶液最大上升高度及溶液上升速度均与矿石粒径负相关。矿堆内由毛细作用形成的不可动溶液含量随矿石平均粒径的减小而增大,细颗粒矿石含量过多时在矿堆内将形成大范围的不可动溶液区域,影响矿堆内溶液渗透效果。  相似文献   

17.
本文结合电刷镀镍-钴-二氧化锆复合镀的试验研究,对非金属固体微粒与金属共沉积机理进行了初步探讨,并讨论了表面活性剂、施镀电压、镀液中固体微粒浓度和微粒尺寸等因素对镀层中非金属微粒沉积量的影响.  相似文献   

18.
《科学通报(英文版)》1998,43(3):210-210
Nanometer sized Au/TiO\-2 particles were synthesized by irradiation of a HAuCl\-4 solution containing colloidal TiO\-2 with light of wavelength (λ)>330 nm. The absorption maximum attributed to the surface plasmon band of gold was observed at 540 nm, a red shift of about 20 nm from the position in aqueous solution. The Au clusters are situated on the surface of TiO\-2 in terms of microcrystallite, which was confirmed by HRTEM, EDS and XRD. The electronic interfaction between the metal and the suport was discussed.  相似文献   

19.
探讨了硫酸作为氧化剂分解含砷难处理金矿的技术可行性,实验结果表明硫酸可以有效地氧化砷黄铁矿而实现金的单体解离,适宜的分解条件为:硫酸与矿粉重量比为3,采用机械搅拌,反应温度240~260℃,分解时间2~3h,分解渣采用硫脲浸出时浸金率高于95%浸金条件为:硫脲浓度1%,三价铁作氧化剂,氧化剂与络合剂比值为0.04~0.06,浸出时间6h图1,表6,参8  相似文献   

20.
Nanometer sized Au/TiO2, particles were synthesized by irradiation of a HAuCl4 solution containing colloidal TiO2 with light of wavelength (λ) > 330 nm. The absorption maximum attributed to the surface plasmon band of gold was observed at 540 nm, a red shift of about 20 nm from the position in aqueous solution. The Au clusters are situated on the surface of TiO2 in terms of microcrystallite, which was confirmed by HRTEM, EDS and XRD. The electronic interfaction between the metal and the suport was discussed.  相似文献   

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