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61.
Molecular imaging, as an emerging technique in current medical diagnostics, therapy and biology science, has received more and more attention in academia, industry, as well as medical practices. And the applications of nanotechnology in this field stimulate its development. This paper explores the development of the basic research and applied research on nano-enhanced molecular imaging, and does the in-depth analysis by adopting the bibliometrics method. The results show that the US is the leader in this field, who has the absolute advantages. Germany, UK and France and Japan are the followed ones. The rapidly developing Asian countries , China and South Korea might become the potential competitors. Research network analysis draws the conclusion that the other countries and regions share the same research interests with the US. The US not only take the lead in the researching number, but also directing the future orientation of this field. However, the US has not much international collaboration. The collaboration within the country and regions show that collaboration in this field is limited to the regional adjacency. Disciplinary analysis reveals that the major subjects which relate intimately to the nano-enhanced molecular imaging are chemistry, biomedical science and material science.  相似文献   
62.
Nanocrystalline solid solution CeO2-Nd2O3 powders were prepared by low temperature combustion process.Special attention was paid to the influence of the glycine/metal ratio and calcination temperature on the powders phase structure, morphology and particle size.TG-DSC curves and XRD peaks of different glycine/metal ratio show that smaller particle size can be obtained with a slightly fuel-deficient ratio.XRD results indicate that the as-prepared powders are crystallized in a single fluorite structure.The crystalline size ranges from 9 to 24 nm, which increases with the increase of calcination temperature.The lower SEM images were characterized by the spongy and form-like microstructure of the powders.Organic agent may be gradually eliminated by high temperature calcination process.  相似文献   
63.
随着Internet的发展,越来越多的企业和个人加入其中,而网终安全成为最为突出的一个问题,防火墙是解决Internet安全问题最有效的方法。  相似文献   
64.
根据目前地基平板载荷试验中存在的一些问题.提出一些建议供工程检测人员及规范制定单位参考.  相似文献   
65.
旋转失速是压缩机的常见故障 ,但诊断该故障时易和其他故障相混淆。本文从旋转失速的振动机理出发 ,归纳了旋转失速的故障识别特征。旋转失速的特征频率是成对出现的 ,随流量的减少而降低。该故障特征在现场诊断时得到验证 ,并成功应用于现场诊断  相似文献   
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The evolution of mining-induced stress field in longwall panel is closely related to the fracture field and the breaking characteristics of strata.Few laborator...  相似文献   
69.
A superior drug controlled release system capable of achieving efficient osteogenesis is in imperative demand because of limited bone substitute tissue for the treatment of bone defect. In the present study, we investigated the potential of using poly(ε-caprolactone)–hydroxyapatite (PCL–HA) composite microspheres as an injectable bone repair vehicle by controlled release of alendronate (AL), a medicine that belongs to the bisphosphonates family. The PCL/HA–AL microspheres were prepared with solid/oil/water emulsion technique, which included two processes: (1) AL was loaded on the hydroxyapatite nanoparticles; (2) the HA–AL complex was built in the PCL matrix. The spherical PCL/HA–AL microspheres were characterized with its significantly improved encapsulation efficiency of hydrophilic AL and better sustained release. Human bone mesenchymal stem cells (hMSCs) were cultured on the surface of these microspheres and exhibited high proliferative profile. Specifically, in osteogenic medium, hMSCs on the surface of PCL/HA–AL microspheres displayed superior osteogenic differentiation which was verified by alkaline phosphatase activity assay. In conclusion, by presenting strong osteogenic commitment of hMSCs in vitro, the PCL/HA–AL microspheres have the potential to be used as an injectable vehicle for local therapy of bone defect.  相似文献   
70.
In order to effectively control petroleum hydrocarbon pollution by immobilisation technology,it is necessary to understanding the degradation pathways of petrol...  相似文献   
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