排序方式: 共有44条查询结果,搜索用时 96 毫秒
1.
建立了毛细管电泳快速检测牙龈卟啉单胞菌(P.g)、齿垢密螺旋体(T.d)、福赛斯坦纳菌(T.f)3种牙周病病原菌种的方法。紫外分光光度法表明,采用无菌吸潮纸尖及PBS缓冲液可以实现牙周病原菌的快速有效提取。对提取的牙周病病原菌种做多聚酶链式反应(PCR)与多重PCR反应,最后以20 cm长,75μm内径的石英毛细管作为分离通道,分离电压4000 V,1.2%羟乙基纤维素(HEC,250 K)为筛分介质,牙周病病原菌菌种P.g,T.d,T.f PCR及多重PCR产物12 min内得到较好分离。结果表明,毛细管电泳与PCR技术相结合,可以实现牙周病原菌种快速鉴定,且检测限低至4.80×10-11ng/μL。方法已用于牙周病原菌菌种的快速检测。 相似文献
2.
3.
LiSi/FeS2热电池失效机理分析 总被引:1,自引:0,他引:1
热电池的失效主要是由于生产环境控制不严导致电池材料吸潮后水份与电极材料发生反应的结果。本文简要分析了热电池失效的三种主要因素。 相似文献
4.
Nano-TiO2 thin films are deposited by radio frequency (RF) magnetron sputtering using TiO2 ceramic target and characterized by X-ray diffractometer, atomic force microscope, and ultraviolet-visible spectrophotometer. The photocatalytic activity is evaluated by light-induced degradation of methyl orange solutions (5, 10, and 20 ppm) using a high pressure mercury lamp as the light source. The film is amorphous, and its energy gap is 3.02 eV. The photocatalytic degradation of methyl orange solution is the first-order reaction and the apparent reaction rate constants are 0.00369, 0.0024, and 0.00151 for the methyl orange solution concentrations of 5, 10, and 20 ppm, respectively. 相似文献
5.
The inelastic electron tunneling spectroscopy of edge-modified graphene nanoribbon-based molecular devices
下载免费PDF全文
![点击此处可从《中国物理 B》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The inelastic electron tunneling spectroscopy(IETS) of four edge-modified finite-size grapheme nanoribbon(GNR)-based molecular devices has been studied by using the density functional theory and Green's function method. The effects of atomic structures and connection types on inelastic transport properties of the junctions have been studied. The IETS is sensitive to the electrode connection types and modification types. Comparing with the pure hydrogen edge passivation systems, we conclude that the IETS for the lower energy region increases obviously when using donor–acceptor functional groups as the edge modification types of the central scattering area. When using donor–acceptor as the electrode connection groups, the intensity of IETS increases several orders of magnitude than that of the pure ones. The effects of temperature on the inelastic electron tunneling spectroscopy also have been discussed. The IETS curves show significant fine structures at lower temperatures. With the increasing of temperature, peak broadening covers many fine structures of the IETS curves.The changes of IETS in the low-frequency region are caused by the introduction of the donor–acceptor groups and the population distribution of thermal particles. The effect of Fermi distribution on the tunneling current is persistent. 相似文献
6.
采用射频磁控溅射TiO2陶瓷靶的方法在硅和石英衬底上制备纳米TiO2薄膜,并经950℃退火1h.通过X射线衍射(XRD)、原子力显微镜(AFM)、紫外可见光谱(UV-Vis)和接触角仪对薄膜相结构、表面形貌、光学性能和亲水性能进行表征.结果表明,与950℃退火1h相比,未退火薄膜是无定形结构并呈现较高的光致亲水性能.退火薄膜是锐钛矿和金红石混合相,其中锐钛矿相质量分数是11.34%.未退火和950℃退火1h的薄膜样品的能隙分别是3.03 eV和3.11 eV.未退火薄膜具有较高的光致亲水性能主要归因于其较低的光学能隙.退火薄膜的热致亲水性能与其相结构、表面清洁度和粗糙度有关. 相似文献
7.
8.
在通信行业中,人们通常把电源比喻为通信系统的“心脏”,而蓄电池则是电源中最重要的部分。据不完全统计,通信电源设备事故中,高压切换事故占20%,高频开关电源事故占10%(强排风,灰尘侵入设备),而蓄电池故障引发的通信事故占到70%。因此,从确保通信质量、生产和财产安全的角度来看,提高蓄电池的维护与管理就显得相当重要了。 相似文献
9.
Ta2O5对TiO2基压敏陶瓷半导化的影响 总被引:3,自引:0,他引:3
研究Ta2O5对(Sr,Bt,St,Ta)掺杂的TiO2基压敏陶瓷半导化的影响,发现随着Ta2O5增加,晶粒电阻呈现“U”字型变化规律,按照配方TiO2+0.3%(SrCO3+Bt2O3+SiO2)+0.1%Ta2O5(摩尔分数)配制的样品的晶粒电阻最小,这表明适当增加施主Ta2O5的含量有助于材料晶粒的半导化。 相似文献
10.