Lentinula edodes, one of the most cultivated edible fungi in the world, are usually neglected for mycotoxins contamination due to the initial thinking of its resistance to mycotoxingenic molds. In the present study, a sensitive and reliable liquid chromatography with tandem mass spectrometry method was developed for the simultaneous quantification of 33 mycotoxins in L. edodes. Targeted mycotoxins were extracted using a quick, easy, cheap, effective, rugged, and safe procedure without any further clean‐up step, and analyzed by liquid chromatography with tandem mass spectrometry on an Agilent Poroshell 120 EC‐C18 column (100 × 3 mm, 2.7 μm) with a linear gradient elution program using water containing 5 mM ammonium acetate and methanol as the mobile phase. After validation by determining linearity (R2 > 0.99), sensitivity (LOQ ≤ 20 ng/kg), recovery (73.6–117.9%), and precision (0.8–19.5%), the established method has been successfully applied to reveal the contamination states of various mycotoxins in L. edodes. Among the 30 tested samples, 22 were contaminated by various mycotoxins with the concentration levels ranging from 3.3–28 850.7 μg/kg, predicting that the edible fungus could be infected by the mycotoxins‐producing fungi. To the best of our knowledge, this is the first report about real mycotoxins contamination in L. edodes. 相似文献
High‐porosity interconnected, thermoresponsive macroporous hydrogels are prepared from oil‐in‐water high internal phase emulsions (HIPEs) stabilized by gelatin‐graft‐poly(N‐isopropylacrylamide). PolyHIPEs are obtained by gelling HIPEs utilizing the thermoresponsiveness of the copolymer components. PolyHIPEs properties can be controlled by varying the aqueous phase composition, internal phase volume ratio, and gelation temperature. PolyHIPEs respond to temperature changes experienced during cell seeding, allowing fibroblasts to spread, proliferate, and penetrate into the scaffold. Encapsulated cells survive ejection of cell‐laden hydrogels through a hypodermic needle. This system provides a new strategy for the fabrication of safe injectable biocompatible tissue engineering scaffolds.
Evidence of internal sulfate attack in field exposure was demonstrated by the damaged interior wall of a three‐year‐old house situated in Nakhon Ratchasima Province, Thailand. Partial distension of the mortar was clearly observed together with an expansion of a black substance. Removal of the black substance revealed a dense black layer. This layer was only found in the vicinity of the damaged area, suggesting that this black material is possibly involved in the wall cracking. By employing synchrotron‐based X‐ray photoelectron spectroscopy (XPS) and X‐ray absorption near‐edge structure (XANES) techniques, the unknown sample was chemically identified. The S 2p and O 1s XPS results mutually indicated the existence of sulfate species in the materials collected from the damaged area. The XANES results indicated the presence of ferrous (II) sulfate, confirming sulfate‐induced expansion and cracking. The sulfate attack in the present case appeared to physically affect the structure whereas the chemical integrity at the molecular level of the calcium silicate hydrate phase was retained since there was a lack of spectroscopic evidence for calcium sulfate. It was speculated that internal sulfate probably originated from the contaminated aggregates used during the construction. The current findings would be beneficial for understanding the sulfate‐attack mechanism as well as for future prevention against sulfate attack during construction. 相似文献
The cell performance and temperature gradient of a tubular solid oxide fuel cell with indirect internal reformer(IIR-SOFC) fuelled by natural gas, containing a typical catalytic packed-bed reformer, a catalytic coated wall reformer, a catalytic annular reformer, and a novel catalytic annular-coated wall reformer were investigated with an aim to determine the most efficient internal reformer system. Among the four reformer designs, IIR-SOFC containing an annular-coated wall reformer exhibited the highest performance in terms of cell power density(0.67 W cm-2)and electrical efficiency(68%) with an acceptable temperature gradient and a moderate pressure drop across the reformer(3.53×10-5kPa).IIR-SOFC with an annular-coated wall reformer was then studied over a range of operating conditions: inlet fuel temperature, operating pressure, steam to carbon(S : C) ratio, gas flow pattern(co-flow and counter-flow pattern), and natural gas compositions. The simulation results showed that the temperature gradient across the reformer could not be decreased using a lower fuel inlet temperature(1223 K–1173 K)and both the power density and electrical efficiency of the cell also decreased by lowering fuel inlet temperature. Operating in higher pressure mode(1-10 bar) improved the temperature gradient and cell performance. Increasing the S : C ratio from 2 : 1 to 4 : 1 could decrease the temperature drop across the reformer but also decrease the cell performance. The average temperature gradient was higher and smoother in IIR-SOFC under a co-flow pattern than that under a counter-flow pattern, leading to lower overpotential and higher cell performance. Natural gas compositions significantly affected the cell performance and temperature gradient. Natural gas containing lower methane content provided smoother temperature gradient in the system but showed lower power density and electrical efficiency. 相似文献
A gas‐phase approach to form Zn coordination sites on metal–organic frameworks (MOFs) by vapor‐phase infiltration (VPI) was developed. Compared to Zn sites synthesized by the solution‐phase method, VPI samples revealed approximately 2.8 % internal strain. Faradaic efficiency towards conversion of CO2 to CO was enhanced by up to a factor of four, and the initial potential was positively shifted by 200–300 mV. Using element‐specific X‐ray absorption spectroscopy, the local coordination environment of the Zn center was determined to have square‐pyramidal geometry with four Zn?N bonds in the equatorial plane and one Zn‐OH2 bond in the axial plane. The fine‐tuned internal strain was further supported by monitoring changes in XRD and UV/Visible absorption spectra across a range of infiltration cycles. The ability to use internal strain to increase catalytic activity of MOFs suggests that applying this strategy will enhance intrinsic catalytic capabilities of a variety of porous materials. 相似文献