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101.
Here a biomimetic approach is presented to fabricate nanodragon fruits featured by a multitude of tiny quantum dot ZnO seeds embedded in mesosilica (SiO2) flesh then enclosed in amorphous calcium phosphate (ACP) shell. The nanodragon fruits give rise to a new class of hybrid ZnO/SiO2@ACP nanocomplex with multimoidal capability: cellular delivering, intracellular targeting, and subcellular imaging. With this particular design, the unusual fluorescent stability of ZnO quantum dots (QDs) in aqueous solution, the specific color selection of the functional ZnO QD seeds, and the stability of transient ACP over a long period of time are made possible. In addition, the nanodragon fruits, capable of targeting mitochondria, have elevated biocompatibility, thus can be of enormous potential applications in treating mitochondrial diseases including inflammation, neurodegeneration, obesity, diabetes, cardiovascular diseases, and cancer. As numerous human disorders are often associated with cellular dysfunctions, this biocompatible carrying platform, capable of delivering, targeting, and imaging subcellular organelles, is therefore highly desirable for efficacious therapeutic and diagnostic treatment.  相似文献   
102.
采用张应力–焦耳热方式对玻璃包覆钴基非晶丝进行退火,测量其退火后的磁滞回线和磁阻抗值,研究张应力退火对玻璃包覆钴基非晶丝静磁性能和巨磁阻抗(GMI)效应的影响。结果表明:通过处理,其各向异性场降低,其中经140MPa张应力退火的样品GMI峰值最大可达80%,所对应的磁场强度降至60A/m。随着玻璃包覆钴基非晶丝内应力的改变,导致样品壳内畴的体积增加,引起应力感生横向各向异性,从而影响GMI效应。  相似文献   
103.
电子束蒸发非晶硅光学薄膜工艺研究   总被引:1,自引:2,他引:1  
研究了沉积时真空室真空度、基片温度和沉积速率对常用电子束蒸发非晶硅(a-Si)光学薄膜的折射率和消光系数的影响。结果表明,在300~1100nm的波长范围内,真空室真空度、基片温度和沉积速率越高,则所得a-Si薄膜折射率越高,消光系数越大。并将实验结果用于半导体激光器腔面高反镜用a-Si膜镀制,发现在选择初始真空为1E-6×133Pa、基片温度为100℃和沉积速率为0.2nm/s时所得高反镜的光学特性比较好,在808nm处折射率和消光系数分别为3.1和1E-3。  相似文献   
104.
Thin films of amorphous tungsten oxide were deposited by sputtering onto glass substrates coated by conductive indium–tin oxide. The films were sputtered at different oxygen-to-argon flow ratios with different pressure and power. Elastic recoil detection analysis determined the density and the stoichiometry. X-ray diffraction measurements showed that the films were amorphous. The films were electrochemically intercalated with lithium ions. At several intercalation levels of each film, the optical reflectance and transmittance were measured in the wavelength range 0.3–2.5 μm. We study the effect of various sputtering conditions on the coloration efficiency of the films and on the luminous and solar optical properties. The O2/Ar ratio and the sputter pressure determine to a large extent the optical absorption. As-deposited sputtered tungsten oxide with sufficiently little oxygen exhibits an absorption peak similar to the case of lithium intercalation.  相似文献   
105.
The crystallization behavior of amorphous CdGexAs2, where the x values were varied from 0 to 1.2, was studied in order to document the effect of germanium on the amorphous structure. The glass-forming tendency of amorphous CdGexAs2 was evaluated by Hruby's criterion. The crystallization mechanism of each group was proposed, interpreting DSC, XRD, EDS, and TEM data, interactively. The crystallization behavior appeared as two distinct groups: those based on the CdAs2 structure and those on the CdGeAs2 structure (chalcopyrite), depending on Ge content. Ge atoms were found to suppress a glass-to-glass exothermic transformation to higher temperatures in the CdAs2 group, and crystallization in both groups. Proposed models of amorphous structure from previous investigators, measuring the radial distribution function, magnetic susceptibility, and macroscopic density, were correlated to the crystallization studies herein. A model of the transformation of glass structure with increasing Ge content from a CdAs2 to a CdGeAs2-like structure was established by extrapolation of experimental results indicating this behavior in crystalline CdGexAs2 compounds with varying x .  相似文献   
106.
采用熔体急冷法制备了Al_(90)Ni_2Y_8和Al_(84)Ni_8Y_8合金条带,并用XRD进行了结构表征,用差示扫描量热仪分析了合金的热稳定性,使用超导量子干涉仪对Al_(90)Ni_2Y_8和Al_(84)Ni_8Y_8非晶态及部分晶化态合金的磁性进行了研究.结果表明,Al_(90)Ni_2Y_8和Al_(84)Ni_8Y_8非晶合金为抗磁性,而且随着Ni含量的增加,合金更容易被磁化.当磁场强度达到0.5T时,Al_(90)Ni_2Y_8合金对应的比磁化强度为-0.083 Am~2/kg,磁化率为-1.66×10~(-5),而Al_(84)Ni_8Y_8合金对应的比磁化强度为-0.091 Am~2/kg,磁化率为-1.82×10~(-5).当合金部分晶化后,合金的磁性仍保持抗磁性,但是比磁化强度的绝对值均显著增加.当磁场强度为0.5 T时,Al_(90)Ni_2Y_8合金对应的比磁化强度的绝对值从急冷态的0.083 Am~2/kg增大到部分晶化后的0.231 Am~2/kg,Al_(84)Ni_8Y_8对应的比磁化强度的绝对值从急冷态的0.091 Am~2/kg增大到部分晶化后的0.163 Am~2...  相似文献   
107.
研究了喷射成形大尺寸La62Al15.7(Cu,Ni)22.3非晶合金在过冷液相区内的塑性变形行为.结果表明,随加热温度的增加和应变速率的减小,该非晶合金由非稳态变形向单一稳态变形行为转变.当应变速率为5×10-3S-1,温度为443 K和挤压比为6.25时,喷射成形La62Al15.7(Cu,Ni)22.3非晶合金样品的密度由挤压前的5.723增加到挤压后的5.924 g/cm3,达到了同成分吸铸态非晶合金密度(6.134 g/cm3)的96.6%.挤压后非晶合金样品依然保持完全非晶态.  相似文献   
108.
During the past several years, giant magneto-impedance effect (GMI) in amorphous wires has generated growing interest in the science community because of theirapplications in sensors. The giant magneto-impedance effect in Co71.8Fe4.9Nb0.8Si7.5B15 amorphous glass-covered wires (AGCW) consists of strong changes in the high frequency impedance with a small DC magnetic field. When f =1 MHz, there is no GMI effect due to the fact that the magnetic penetration depth is higher than their radius. As the frequency increases, the GMI effect becomes important in both the glass-covered wire and the wire afterglass removal. Field dependence of the impedance has a similar behaviour to the AGCW ones, when a tensile stress is applied to the wire without glass cover.  相似文献   
109.
110.
新型铁基非晶合金的研究   总被引:4,自引:0,他引:4  
本文研究的新型铁基软磁非晶合金,既具有1.8T的高饱和磁感应强度,又具有相当钻基非晶合金的低的高频损耗、低矫顽力等特性,该合金还克服了超微晶材料的脆性和可加工性差的缺点,可用于直线感应加速器、压缩开关、磁放大器及逆变电源等设备中,命名为1K104。  相似文献   
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