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811.
812.
Orthorhombic distorted K2NiF4-type (Ca1+xNd1?x)CrO4 (0.00  x  0.15) was synthesized using a standard ceramic technique. The cell parameters (a and c) decreased, whereas the cell parameter (b) increased with the increase in x. The variation in the global instability index (GII) indicated that the crystal stability of (Ca1+xNd1?x)CrO4 was not influenced by the Cr4+ ion content. At all temperatures, the electrical conductivity (σ) of (Ca1+xNd1?x)CrO4 increased with the increase in x. (Ca1+xNd1?x)CrO4 was a p-type semiconductor and exhibited hopping conductivity in a small-polaron model in the temperature range of 290 K  T  713 K. The Cr4+ ion acts as an acceptor, and the electron transfer through the Cr3+–O–Cr4+ path becomes active as a result of the Cr4+ ion content and the Cr–O(1) distance.  相似文献   
813.
扁平多分支管内两相流流量分配的数值模拟   总被引:2,自引:0,他引:2  
利用FLUENT软件,对一水平矩形扁平多分支管内,氮气和水为工质的气液两相流流量分配问题进行了数值模拟,并与实验数据进行了对比.数值模拟计算分析了相间曳力作用模型、气液进口条件、壁面粗糙度、离散相直径、结构参数对两相流流量分配的影响,指出为了提高模拟计算准确度,需要改进和完善现有模型.  相似文献   
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Herein, we report an ATP-responsive nanoparticle (GroELNP) whose surface is fully covered with the biomolecular machine “chaperonin protein GroEL”. GroELNP was synthesized by DNA hybridization between a gold NP with DNA strands on its surface and GroEL carrying complementary DNA strands at its apical domains. The unique structure of GroELNP was visualized by transmission electron microscopy including under cryogenic conditions. The immobilized GroEL units retain their machine-like function and enable GroELNP to capture denatured green fluorescent protein and release it in response to ATP. Interestingly, the ATPase activity of GroELNP per GroEL was 4.8 and 4.0 times greater than those of precursor cysGroEL and its DNA-functionalized analogue, respectively. Finally, we confirmed that GroELNP could be iteratively extended to double-layered NP.  相似文献   
816.
Adhesives/sealants are used after suturing to prevent leakage of cerebrospinal fluid from an anastomotic site. Commercial adhesives/sealants have been used to close the cerebral dura. However, swelling of the cured adhesives/sealants induces increased intracranial pressure and decreases the strength of the seal. In the present study, tissue adhesive hydrogels with improved swelling property using inclusion complex composed of α-cyclodextrin (αCD) and decyl group (C10)-modified Alaska pollock-derived gelatin (C10-ApGltn) with a high degree of substitution (DS) (>20 mol%) are developed. Viscosity of C10-ApGltn with a high DS solution remarkably decreased by the addition of αCD. The resulting αCD/C10-ApGltn adhesive hydrogel composed of αCD/C10-ApGltn inclusion complexes and poly(ethylene glycol) (PEG)-based crosslinker showed improved swelling property after immersion in saline. Also, the resulting adhesive has a significantly higher burst strength than fibrin-based adhesives and is as strong as a PEG-based adhesive. Quantitative analysis of αCD revealed that the improved swelling property of the resulting adhesive hydrogels is induced by the release of αCD from cured adhesive, and the subsequent assembly of decyl groups in the saline. These results suggest that adhesives developed using the αCD/C10-ApGltn inclusion complex can be useful for closing the cerebral dura mater.  相似文献   
817.
We present an electrochemical-lossy mode resonance (LMR) sensing method that detects refractive indices and electroactive species. The LMR peaks of indium-tin-oxide in the transmittance-wavelength spectra were significantly shifted as the applied potential between 1.0 and −0.5 V at 209 nm/V. The modulation was exploited for sensing the refractive index and electroactive species (ferrocyanide and methylene blue) in two ways: peak-wavelength tracking and potential scanning. The potential-scanning technique produced clear potential LMR peaks in the transmittance-potential spectra for the first time, which were corresponded to the external refractive index. Meanwhile, the limits of detection of ferrocyanide and methylene blue were 7.5 and 25.3 μM, respectively, in peak-wavelength tracking and 18.2 and 20.8 μM, respectively, in the potential scanning technique.  相似文献   
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Aoyagi  Tomohiro  Ohtsubo  Kouichi 《Optical Review》2023,30(3):376-386
Optical Review - The fundamental formula in an optical system is Rayleigh diffraction integral. In practice, we deal with Fresnel diffraction integral as approximate diffraction formula. Fresnel...  相似文献   
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