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481.
Response to the “Comment on Chemical and Toxicological Investigations of a Previously Unknown Poisonous European Mushroom Tricholoma terreum” 下载免费PDF全文
Dr. Xia Yin Dr. Tao Feng Zheng‐Hui Li Prof. Dr. Ji‐Kai Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(16):5789-5792
Recently, Dr. Paolo Davoli and his colleagues stated that the conclusions drawn by us were misleading from a mycotoxicological perspective, as they cast doubts on the edibility of a mushroom species (Tricholoma terreum) that has been always recognized as safe. Unfortunately, they made a mistake, and seriously misinterpreted our data, which resulted in scepticism of our research. Saponaceolides B and M were tested for their stabilities heating directly on and boiling in water. It is undoubted that both saponaceolides B and M are capable of withstanding prolonged heating during cooking. 相似文献
482.
Pattern imprinting in deep sub-micron static random access memories induced by total dose irradiation 下载免费PDF全文
Pattern imprinting in deep sub-micron static random access memories(SRAMs) during total dose irradiation is investigated in detail. As the dose accumulates, the data pattern of memory cells loading during irradiation is gradually imprinted on their background data pattern. We build a relationship between the memory cell’s static noise margin(SNM) and the background data, and study the influence of irradiation on the probability density function of ?SNM, which is the difference between two data sides’ SNMs, to discuss the reason for pattern imprinting. Finally, we demonstrate that, for micron and deep sub-micron devices, the mechanism of pattern imprinting is the bias-dependent threshold shift of the transistor, but for a deep sub-micron device the shift results from charge trapping in the shallow trench isolation(STI) oxide rather than from the gate oxide of the micron-device. 相似文献
483.
A new approach based on the Monte Carlo simulation is used to calculate the infinite matrix dose rate correction factors of gamma, beta and internal conversion radiations for 250 μm diameter grains of quartz and TLD500 chips. Here, the dependence of the correction factor on the radiation energy is initially calculated for each type of emitted particle and with this result the correction factors for the 232Th and 238U series and 40K are determined. This analysis is made for dry soil and also for different levels of water content in it. The obtained beta correction factors for quartz are in good agreement with those previously reported. For the TLD500 chip certain differences with previously reported data are found. The analysis of the gamma water correction factor for quartz based on Zimmerman equation shows the correspondence with the similar correction factor for electrons. In the case of TLD500 chip a gamma water correction factor value of 1.0 was found. 相似文献
484.
选择了四种典型双极集成电路,在两种不同剂量率下,开展了不同温度的高温辐照加速实验,测量了典型双极集成电路的辐射敏感参数在不同高温辐照下的变化规律。实验结果表明:高温辐照能够给出空间低剂量率辐射损伤增强效应的保守估计,且存在最佳辐照温度,最佳辐照温度随总剂量的增加向低温区漂移,随剂量率的增大向高温区漂移,在相同剂量率和总剂量下,输入级为NPN晶体管的双极集成电路比输入级为PNP晶体管的最佳辐照温度低。 相似文献
485.
《Biomedical chromatography : BMC》2017,31(5)
A rapid, specific and high‐throughput stable isotope‐dilution LC–MS/MS method was developed and validated with high sensitivity for the quantification of R‐ phencynonate (a eutomer of phencynonate racemate) in rat and dog plasma. Plasma samples were deproteinized using acetonitrile and then separated on a C8 column with an isocratic mobile phase containing acetonitrile–water–formic acid mixture (60:40:0.1, v /v/v) at a flow rate of 0.2 mL/min. Each sample had a total run time of 3 min. Quantification was performed using triple quadrupole mass spectrometry in selected reaction monitoring mode with positive electrospray ionization. The method was shown to be highly linear (r 2 > 0.99) and to have a wide dynamic range (0.1–100 ng/mL) with favourable accuracy and precision. No matrix effects were observed. The detailed pharmacokinetic profiles of R‐ phencynonate at therapeutic doses in rats and dogs were characterized by rapid oral absorption, quick clearance, high volume of distribution and poor absolute bioavailability. R‐ Phencynonate lacked dose proportionality over the oral dose range, based on the power model. However, the area under concentration–time curve and the maximum plasma concentration increased linearly in a dose‐dependent manner in both animal models. The absolute bioavailability of R‐ phencynonate was 16.6 ± 2.75 and 4.78 ± 1.26% in dogs and rats, respectively. 相似文献
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489.
Authors have elaborated a method which allows a digital computer to be applied for the calculaiton of the relative irradiation dose rates of the K-120.000 60Co gamma irradiation source with a specific activity of 80.000 Ci. The model used takes into consideration is the joint effect of 80 source-elements which were one-dimensional but of different activities and arranged in four layers one above the other, around one/two imaginary cylinder superficies. In possession of chemical or physical dosimetry data this method can be applied also for the calculation of the absolute irradiation dose ratres. According to the experiences obtained so far, over a distance of 6 cm-s from the source-elements the error of the computed absolute irradiation dose rate data is less than 5%. 相似文献
490.
Zur Darstellung der Einheit der Energiedosis von Quantenstrahlung für Energien oberhalb von 0,4 MeV wurde im ASMW eine Normalmeßeinrichtung geschaffen, deren Hauptbestandteil ein quasiadiabatisches Differentialkalorimeter ist. Der Aufbau und die Wirkungsweise der Normalmeßeinrichtung werden erläutert. Als Bezugsmaterial für die absolute Bestimmung der Energiedosis dient Graphit. Die Korrektionsfaktoren, die in die Bestimmungsgleichung für die Energiedosis eingehen, werden kurz diskutiert. Die untere Meßgrenze der Einrichtung liegt bei 10?1 Gy, wobei die Meßunsicherheit 1,4% betrāgt. 相似文献