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191.
“Saturnized fullerene C60 molecules” were designed as the cardinal points for cross-linked polymers. Results from the graphic molecular modeling, including the CVFF calculations, indicate that the 1, 2-adduct [-N(CH2)6-]6·C6oH6with S6 symmetry is the best target molecule.  相似文献   
192.
A simple radiation-hard process for rapid thermal reoxidized nitrided oxide (RNO) structures is proposed. This process involves fast pulling (FP) of samples out of the furnace in a mixture of oxygen and nitrogen immediately after the oxidation has been completed. Samples with starting oxides prepared by conventional postoxidation annealing (POA) are also compared. It is found from CV curves that the initial interface property of an RNO structure with a fast pulled starting oxide (RNOFP) is almost the same as that with a postoxidation annealed starting oxide (RNOPOA); however, after being exposed to Co-60 irradiation, the former becomes superior to the latter. Excess oxygen left at interface in the starting oxide during the fast pulling procedure might be the origin of the radiation-hard property for RNOFP structures  相似文献   
193.
The radiation hardness of MOS capacitors with various reoxidized nitrided oxide (RNO) structures was studied by changing the duration of rapid thermal processes during sample preparation and by applying irradiation-then-anneal (ITA) treatments on samples after preparation. It was found that the initial flatband voltage and midgap interface trap density of MOS capacitors exhibit turnaround dependency on the total time of nitridation and reoxidation processes. For samples with nitrided oxide (NO) structures, the radiation-induced variations of the above parameters are also turnaround-dependent on nitridation time. However, when the reoxidation process is performed, the radiation hardness for all samples is gradually improved with increasing reoxidation time no matter when the nitridation time. The most radiation-hard process for RNO structures is suggested. Finally, it was found that when ITA treatments are applied on samples after preparation, their radiation hardness is much improved  相似文献   
194.
195.
We synthesized AuPt alloyed nanoparticles in colloidal solution by a one-pot procedure based on synchrotron x-ray irradiation in the presence of PEG (polyethylene glycol). The exclusive presence of alloyed nanoparticles with fcc structure was confirmed by several different experiments including UV-vis spectroscopy, x-ray diffraction (XRD) and transmission electron microscopy (TEM). The composition of the AuPt alloyed nanoparticles can be varied in a continuous fashion by simply varying the feed ratios of Au and Pt precursors. The nanoparticles exhibited colloidal stability and biocompatibility, important for potential applications.  相似文献   
196.
Multifunctional nanoparticles are synthesized for both pH‐triggered drug release and imaging with radioluminescence, upconversion luminescent, and magnetic resonance imaging (MRI). The particles have a yolk‐in‐shell morphology, with a radioluminescent core, an upconverting shell, and a hollow region between the core and shell for loading drugs. They are synthesized by controlled encapsulation of a radioluminescent nanophosphor yolk in a silica shell, partial etching of the yolk in acid, and encapsulation of the silica with an upconverting luminescent shell. Metroxantrone, a chemotherapy drug, was loaded into the hollow space between X‐ray phosphor yolk and up‐conversion phosphor shell through pores in the shell. To encapsulate the drug and control the release rate, the nanoparticles are coated with pH‐responsive biocompatible polyelectrolyte layers of charged hyaluronic acid sodium salt and chitosan. The nanophosphors display bright luminescence under X‐ray, blue light (480 nm), and near infrared light (980 nm). They also served as T1 and T2 MRI contrast agents with relaxivities of 3.5 mM?1 s?1 (r1) and 64 mM?1s?1 (r2). These multifunctional nanocapsules have applications in controlled drug delivery and multimodal imaging.  相似文献   
197.
Predicated execution is a promising architectural feature for exploiting instruction-level parallelism in the presence of control flow. Compiling for predicated execution involves converting program control flow into conditional, or predicated, instructions. This process is known as if-conversion. In order to apply ifconversion effectively, one must address two major issues: what should be ifconverted and when the if-conversion should be performed. A compiler's use of predication as a representation is most effective when large amounts of code are if-converted and when if-conversion is performed early in the compilation procedure. On the other hand, efficient execution of code generated for a processor with predicated execution requires a delicate balance between control flow and predication. The appropriate balance is tightly coupled with scheduling decisions and detailed processor characteristics. This paper presents a compilation framework based on partial reverse if-conversion that allows the compiler to maximize the benefits of predication as a compiler representation while delaying the final balancing of control flow and predication to schedule time.  相似文献   
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