A novel catalyst of silver microparticles embedded in a silicon nanowire array support (Ag@SiNW) was prepared by an in situ electroless metal deposition method; it exhibited high selectivity and stability for gas-phase oxidation of high alcohol to its corresponding aldehyde. 相似文献
A novel two-dimensional (2-D) tilt sensor is demonstrated by incorporating only two fiber Bragg gratings (FBGs) with a hybrid pendulum transducer. The pendulum transducer is specially designed with hollow half at the upper side and solid half at the lower side. Two FBGs were attached on the surface separated by one fourth of the circumference of the rod of pendulum and across the interface of its hollow and solid parts. Reflection peaks of FBGs split by the applied tilt angle. 2-D tilt angle can be determined by monitoring the wavelength separations of the split peak in two FBGs, which is inherently insensitive to temperature. In the experiment, a sensitivity of 0.054 nm/° over a wide range of 20º has been achieved, with the accuracy of 0.27°. 相似文献
Depolymerized lignin products are very complex mixtures. Based on a depolymerization solution of commercially available sodium lignosulfonate under mild conditions, a fast and efficient method for the separation and direct characterization of the degree and efficiency of the acid‐catalyzed depolymerization of lignin was developed in this study. Using an ultraviolet detector, the depolymerized lignosulfonate products were well separated and characterized according to the relative molar mass distribution on an advanced polymer chromatographic system with three ethylene‐bridged hybrid columns having small pore sizes (45 Å) in series and tetrahydrofuran as the mobile phase. The developed advanced polymer chromatography method enabled the detection of low‐molecular‐weight lignin degradation products (Mn = 260–1100 Da) with high peak resolutions in less than 7.2 min. Furthermore, preliminary advanced polymer chromatography studies to determine the influence of reaction temperature on the depolymerized products indicated that the depolymerized aromatics fell in several molecular weight ranges with an extremely low dispersity. This new approach can be used for the rapid analysis of lignin depolymerization products. 相似文献
The histone lysine methyltransferase EZH2 has been reported to play important roles in cancer aggressiveness, metastasis and poor prognosis. In this study, a series of benzomorpholine derivatives were synthesized and biologically evaluated as EZH2 inhibitors. The target compounds were obtained in good yields from 3-amino-5-bromo-2-hydroxybenzoic acid via cyclization, Suzuki coupling and amidation as the key steps. A preliminary optimization study led to the discovery of several potent novel EZH2 inhibitors (6b, 6c, 6x and 6y). Moreover, 6y inhibited the A549 and NCI-H1975 cell lines (IC50?=?1.1 µM and 1.1 µM, respectively). Further studies indicated that 6y can reduce EZH2 expression in intact cells and cause cell arrest in the G2/M phase.
The education characters of emerging engineering education (3E) is summarized. The necessary for reform and construction of new chemistry-related majors based on the ideal of 3E is discussed. The main ideas and ways proposed and the main research progresses made by the Instructional Committee of Chemistry Majors, Mistry of Education are briefly introduced with emphasis on the setup of two new majors namely "Chemistry Metrology and Technology" and "Intelligent Molecular Engineering" and reform of "Energy Chemistry". It is of guidance significance for the future reform of chemistry-related majors based on the 3E idea. 相似文献
A novel two-dimensional tilt sensor with a large measurement range is demonstrated by using four fiber Bragg gratings (FBGs) attached on a cylindrical cantilever-based pendulum. Experimental results show that tilt accuracy of ±0.2° and resolution of 0.013° have been achieved in the range of −40°-40°. The temperature effect is automatically eliminated without additional temperature compensation elements. 相似文献
Surface effects on the persistence length of quasi-one-dimensional nanomaterials are investigated by using the theory of surface elasticity and the core–shell model of nanobeams. A simple and unified expression is provided to determine the persistence length of nanowires and nanotubes with any regular polygonal cross-sections. It is demonstrated that surface effects have a distinct influence on the persistence length when the characteristic sizes of materials shrink to nanometers. This work is helpful not only for understanding the size-dependent behavior of nanomaterials but also for the design of devices based on nanotubes or nanowires. 相似文献