A Ce(III)-catalyzed, visible-light induced aerobic oxidative dehydrogenative coupling reaction between glycine derivatives and electron-rich arenes is disclosed. The protocol proceeds efficiently under mild conditions, providing an efficient method for the rapid synthesis of α-arylglycine derivatives without the need for an external photosensitizer and additional oxidant. Moreover, this protocol could be performed on a 5 mmol scale, without obvious reduction of the efficiency.
The effect of organic phase concentration,saponifier type ,saponification ratio of organic phase and raw solution acidity on saturated extraction amount,distribution ration and separation coefficient,which was made by extracting HDEHP in sulphuric acid medium was investigated The optimum condition was get The distribution ration and separation coefficient of light rare earths was determined
Abstract The influences of Mo on the structures and the electronic properties of passive films on Nil6C Χ Mo ( Χ =0wt.%, 2wt.%, 5wt.%, 8wt.%, 12wt.% and 16wt.%) alloys in pH 1.0 sulfuric acid solution, pH 8.5 borate buffer solution and pH 13 sodium hydroxide solution were investigated using X-ray photoelectron spectroscopy (XPS), potentiodynamic polarization curve, Electrochemical impedance spectroscopy (EIS) and Mott-Schottky plot. The results showed that the addition of Mo can evidently refine the microstructure of Ni16Cr alloy, and the grain size sharply decreased with increasing Mo. Ni16Cr alloy was passivated in pH1 sulfuric acid solution, pH8.5 borate buffer solution and pH13 sodium hydroxide solution, each passive current density decreased and each passive potential region enlarged with the increment of Mo. XPS results showed that the passive films on Ni16CΧMo alloys were mainly composed of the inner Cr 2 s 3 layer and the outer NiO layer with a little amount of Cr 2 S 3 , NiS and NiSO 4 . The resistances and compactness of the passive films on Ni16Cr alloy in the three solutions increased with the increased Mo, which implyed the enhanced protection of the passive film. Mott-Schottky plots revealed that the passive film on Ni16Cr alloy appeared the p-n heterojunction, the defect number of the outer film increased with the increment of Mo, while for the inner film, the defect number decreased with Mo, while the total protection of the passive films to the metal matrix was improved with increasing Mo.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Removing heavy metal ions from industrial wastewater is one of the most important and difficult areas of the water treatment industry. In this study, Bacterial Cellulose/Polyvinyl Alcohol/Graphene Oxide/Attapulgite (BC/PVA/GO/APT) composites were successfully prepared via a repeated freeze-thaw method using bacterial cellulose, polyvinyl alcohol as the skeleton, and graphene oxide, attapulgite as fillers. The capacities of adsorbing Cu2+ and Pb2+ ions in solution were investigated. FTIR, XRD, SEM, BET, and TG-DSC analyses showed that the BC/PVA/GO/APT hydrogel has a better hydrophilicity, a larger specific surface area and a better thermal stability than traditional materials. We found that the adsorption of Cu2+ and Pb2+ ions can be accurately predicted by the Freundlich kinetic model, and the optimal adsorption capacities of these ions were found to be 150.79 mg/g and 217.8 mg/g respectively. Thermodynamic results showed that the adsorption process is spontaneous and exothermic. BC/PVA/GO/APT composites are suggested to be an ideal adsorption material for removing heavy metal ions from industrial wastewater.
Abstract This paper introduced a silicon resonant pressure sensor based on thermal stress-matched structures to extend the operating temperature range. The sensor designed this time consists of an SOI wafer with a pressure-sensitive diaphragm for pressure sensing and two integrated resonators, a silicon wafer for vacuum packaging, and a glass wafer for additional stress isolation. The multilayer structures were bonded together to form a thermal stress-matched part to address the problem of temperature inflection points of conventional resonant pressure sensors within broad temperature zones. Finite element analyses optimized the sensor’s pressure- and temperature-sensitive characteristics. Micromachining based on eutectic and anodic bonding to fabricate sensor chips. Characterization results indicated the developed pressure sensor can work stably in a wide temperature range of -55∼125°C and has excellent fitting accuracy exceeding ±0.01% FS., which showed a better performance than previously reported counterparts.
Lithium-sulfur batteries have garnered significant interest as potential energy storage systems for the future, owing to their remarkable theoretical specific capacity (1675 mA h g
The research on the mechanism of roast reaction of Baotou rare earth concentrate added by 25% Na 2CO 3 was carried out by using thermal analysis,X ray diffraction and chemical analysis.RECO 3F was first decomposed into REOF and CeO 2 as roasting at 348～455℃,then REPO 4 was decomposed into RE 2O 3 as roasting at 577～665℃.The kinetics of roast reaction was calculated,at 348～455℃,E=150kJ·mol -1 ,n=0 87,A=1.84×10 11 S -1 ·mol -1 ,k=0.398(T=712k);and at 577～665℃,E=229kJ·mol -1 ,n=1.18,A=6.14×10 9S -1 ·mol -1 ,k=1 06×10 -3 (T=921k).F 1=-ln(1-α) was calculated to be the equation of the mechanism of roast reaction in two stages from thermogravimetric curves.
The microscopic mechanisms underpinning the spontaneous surface passivation of metals from ubiquitous water have remained largely elusive. Here, using in situ environmental electron microscopy to atomically monitor the reaction dynamics between aluminum surfaces and water vapor, we provide direct experimental evidence that the surface passivation results in a bilayer oxide film consisting of a crystalline-like Al(OH)3 top layer and an inner layer of amorphous Al2O3. The Al(OH)3 layer maintains a constant thickness of ~5.0 Å, while the inner Al2O3 layer grows at the Al2O3/Al interface to a limiting thickness. On the basis of experimental data and atomistic modeling, we show the tunability of the dissociation pathways of H2O molecules with the Al, Al2O3, and Al(OH)3 surface terminations. The fundamental insights may have practical significance for the design of materials and reactions for two seemingly disparate but fundamentally related disciplines of surface passivation and catalytic H2 production from water.
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