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171.
In this paper the results of structural analysis of the SnO2 and In2O3 films deposited by spray pyrolysis are presented. The main goals of this analysis are summarizing the results obtained in this field, highlighting a correlation between parameters of film deposition and the material structure and formulating some general regularities, typical for metal oxides. Peculiarities and mechanisms of pyrosol deposition as well as advantages and disadvantages of this technology for deposition of the films with required parameters were also discussed. It is shown that this technology has great potential for controlling structural parameters of metal oxides such as thickness, the grain size, texturing, roughness, the grain faceting and the porosity.  相似文献   
172.
N-substituted anilines react with triethanolamine in the presence of a catalytic amount of a homogeneous ruthenium catalyst to give the corresponding 1-substituted indoles in good yields.  相似文献   
173.
174.
In this paper we study a double phase problem with an irregular obstacle. The energy functional under consideration is characterized by the fact that both ellipticity and growth switch between a type of polynomial and a type of logarithm, which can be regarded as a borderline case of the double phase functional with (p,q)-growth. We obtain an optimal global Calderón–Zygmund type estimate for the obstacle problem with double phase in the borderline case.  相似文献   
175.
Herein, two unit of β-cyclodextrin linked by thiomethylene bridge was synthesized and employed as a novel efficient supramolecular host for the synthesis of biologically active chromenones templates via three-component single-pot reaction. A possible reaction mechanism through molecular complexation is suggested based on 2D ROESY NMR spectroscopic analysis. Moreover, the catalyst could be easily recycled, while a 94% yield and 89% rate of catalyst recovery could be achieved after four cycles of catalyst recycling. Environmentally benign reaction conditions, excellent yields, and avoidance of organic solvent and conventional isolation as well as purification are the noteworthy credits of this developed protocol.  相似文献   
176.
177.
Toward the goal of smart sensor systems for wearable electronics, polymer microfiber‐based free‐standing sensors benefit from excellent flexibility, decent ductility, and easy wearability in comparison with thin‐film‐based sensing devices. Herein, we report a hydrophobic and conducting single‐strand microfiber‐based liquid‐phase chemical sensor consisting of polyurethane (PU), tin oxide (SnO2), and carbon nanotube (CNT) composites with applying a (1H,1H,2H,2H‐heptadecafluorodec‐1‐yl) phosphonic acid (HDF‐PA)‐based self‐assembled monolayer. The free‐standing HDF‐PA‐treated PU–SnO2–CNT composite microfiber showing selective filtering properties with the repellency of water and the penetration of an organic solvent is electrically and mechanically characterized. Finally, the single‐strand HDF‐PA‐treated PU–SnO2–CNT composite microfiber‐based chemical sensor, which shows excellent mechanical properties and aqueous stability, is demonstrated to detect the presence of a chemical in pure water or counterfeit gasoline in pure gasoline by observing mechanical changes, especially variations in the length and diameter of the fiber, and monitoring the electrical resistance change. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 495–502  相似文献   
178.
The purpose of this study was to measure the radiation exposure to operator and patient during cardiac electrophysiology study, radiofrequency catheter ablation and cardiac device implantation procedures and to calculate the allowable number of cases per year. We carried out 9 electrophysiology studies, 40 radiofrequency catheter ablation and 11 cardiac device implantation procedures. To measure occupational radiation dose and dose–area product (DAP), 13 photoluminescence glass dosimeters were placed at eyes (inside and outside lead glass), thyroids (inside and outside thyroid collar), chest (inside and outside lead apron), wrists, genital of the operator (inside lead apron), and 6 of photoluminescence glass dosimeters were placed at eyes, thyroids, chest and genital of the patient. Exposure time and DAP values were 11.7?±?11.8?min and 23.2?±?26.2?Gy?cm2 for electrophysiology study; 36.5?±?42.1?min and 822.4?±?125.5?Gy?cm2 for radiofrequency catheter ablation; 16.2?±?9.3?min and 27.8?±?16.5?Gy?cm2 for cardiac device implantation procedure, prospectively. 4591 electrophysiology studies can be conducted within the occupational exposure limit for the eyes (150?mSv), and 658-electrophysiology studies with radiofrequency catheter ablation can be carried out within the occupational exposure limit for the hands (500?mSv). 1654 cardiac device implantation procedure can be conducted within the occupational exposure limit for the eyes (150?mSv). The amounts of the operator and patient's radiation exposure were comparatively small. So, electrophysiology study, radio frequency catheter ablation and cardiac device implantation procedures are safe when performed with modern equipment and optimized protective radiation protect equipment.  相似文献   
179.
In this work, a projection algorithm is considered for treating strongly continuous semigroups of demicontinuous pseudocontractions. Theorems of strong convergence of fixed points are established in the framework of real Hilbert spaces.  相似文献   
180.
A m-xylene bridged imidazolium receptor 1 has been designed and synthesized. The receptor 1 utilizes two imidazole (C–H)+—anion hydrogen bonds and one aromatic hydrogen—anion hydrogen bond. The major driving force of complexation between the receptor 1 and anions comes from two imidazole (C–H)+—anion hydrogen bonding. However, some hydrogen bonding energy between aromatic hydrogen and anion exists, although it is expected to be much smaller than that of imidazole (C–H)+—anion hydrogen bonds.

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