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Multimedia Tools and Applications - Endometriosis is a common gynecologic condition typically treated via laparoscopic surgery. Its visual versatility makes it hard to identify for non-specialized...  相似文献   
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Catalysts of quaternary composition have been prepared and tested for the Sabatier process. For catalyst syntheses the following techniques have been used: sol‐gel methods, wet impregnation and incipient wetness impregnation. The Sabatier reaction was carried out at temperatures between 520 K and 670 K, pressures of 15 bar and 30 bar using a mixture H2:CO2 of 4:1. Activity screening of the microscale wall catalysts was performed by a custom‐built 10‐fold parallel gas‐flow microreactor setup in sequential operating mode. To analyze the gas phase compositions GC‐FID was used.  相似文献   
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A nanocomposite material based on copper(II) oxide (CuO) and its utilization as a highly selective and stable gas‐responsive electrical switch for hydrogen sulphide (H2S) detection is presented. The material can be applied as a sensitive layer for H2S monitoring, e.g., in biogas gas plants. CuO nanoparticles are embedded in a rigid, nanoporous silica (SiO2) matrix to form an electrical percolating network of low conducting CuO and, upon exposure to H2S, highly conducting copper(II) sulphide (CuS) particles. By steric hindrance due to the silica pore walls, the structure of the network is maintained even though the reversible reaction of CuO to CuS is accompanied by significant volume expansion. The conducting state of the percolating network can be controlled by a variety of parameters, such as temperature, electrode layout, and network topology of the porous silica matrix. The latter means that this new type of sensing material has a structure‐encoded detection limit for H2S, which offers new application opportunities. The fabrication process of the mesoporous CuO@SiO2 composite as well as the sensor design and characteristics are described in detail. In addition, theoretical modeling of the percolation effect by Monte‐Carlo simulations yields deeper insight into the underlying percolation mechanism and the observed response characteristics.  相似文献   
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Metallurgical and Materials Transactions B - Flow measurements are performed in a slab model for continuous casting of steel under the influence of a ruler type Electromagnetic Brake (EMBr). The...  相似文献   
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We explore the possibility of characterizing sperm cells without the need to stain them using spectral and fluorescence lifetime analyses after multi-photon excitation in an insect model. The autofluorescence emission spectrum of sperm of the common bedbug, Cimex lectularius, was consistent with the presence of flavins and NAD(P)H. The mean fluorescence lifetimes showed smaller variation in sperm extracted from the male (tau m, τm = 1.54–1.84 ns) than in that extracted from the female sperm storage organ (tau m, τm = 1.26–2.00 ns). The fluorescence lifetime histograms revealed four peaks. These peaks (0.18, 0.92, 2.50 and 3.80 ns) suggest the presence of NAD(P)H and flavins and show that sperm metabolism can be characterized using fluorescence lifetime imaging. The difference in fluorescence lifetime variation between the sexes is consistent with the notion that female animals alter the metabolism of sperm cells during storage. It is not consistent, however, with the idea that sperm metabolism represents a sexually selected character that provides females with information about the male genotype.  相似文献   
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To develop new polymer-based materials, the design of aliphatic carbonate has received attention and become a well-known cyclic monomer. In view of carbonate ring polymer scope, poly(trimethylene carbonate) (PTMC) has been continuously developed for further applications due to its unique degradability. PTMC bearing oligo ethylene glycol units, PTMCM-MOE3OM, were typically prepared via ring-opening polymerization (ROP) using amidine-based catalysts such as 1,8-diazabicyclo[5.4.0] undec-7-ene (DBU) and benzyl alcohol (BnOH) as an initiator. To improve the polymer molecular weight or other properties, several know-how synthetic catalysts based on organometallic complexes are under consideration as potential catalysts. With the existence of diverse classes of metallic complexes, the inorganic complexes were investigated for their catalytic activity based on tris(dimethylsilyl)amido chelating, bis(phenolate) chelating, and macrocyclic tetradentate (NNNN)-type cyclen chelating with a metal-core of tin (II), scandium (III), lutetium (III), and zinc (II). In this study, we found that involving a Zn(II) dimethylcyclen/alkoxide ligand and Mg complexes could accelerate the reaction and finish the polymerization under ambient conditions within 2 hr. Molecular weight reached 11,000 g/mol (40%) and 8,100 g/mol (> 96%). Subsequently, we concluded that Zn and Mg complexes were high reactivity for initiating the ROP of TMCM-MOE3OM upon steadily degree of polymerization.  相似文献   
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