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关键词： X-ray spectroscopy   x ray photoelectron spectrometer   surface science   surface chemistry   surface of a catalyst   co oxidation   single crystal model catalysts   ap xps   hydrogenation of carbon dioxide   water gas shift   partial oxidation of methane   complete oxidation of methane   coupling of methane   dry or steam reforming of methane   reduction of nitric oxide   developing catalysts   photocatalysis   nanoparticle catalyst  

ISBN: (数字)9781119845485 ISBN: (纸本)9781119845447

摘要： APPLICATION OF AMBIENT PRESSURE X-RAY PHOTOELECTRON SPECTROSCOPY TO CATALYSIS Authoritative and detailed reference on ambient-pressure x-ray photoelectron spectroscopy for practitioners and researchers starting in the field Application of Ambient Pressure X-ray Photoelectron Spectroscopy to Catalysis introduces a relatively new analytical method and its applications to chemistry, energy, environmental, and materials sciences, particularly the field of heterogeneous catalysis, covering its background and historical development, its principles, the instrumentation required to use it, analysis of data collected with it, and the challenges it faces. The features of this method are described early in the text; the starting chapters provide a base for understanding how AP-XPS tracks crucial information in terms of the surface of a catalyst during catalysis. The second half of this book delves into the specific applications of AP-XPS to fundamental studies of different catalytic reactions. In later chapters, the focus is on how AP-XPS could provide key information toward understanding catalytic mechanisms. To aid in reader comprehension, the takeaways of each chapter are underlined. In Application of Ambient Pressure X-ray Photoelectron Spectroscopy to Catalysis , readers can expect to find detailed information on specific topics such as: Going from surface of model catalyst in UHV to surface of nanoparticle catalyst during catalysis Application of XPS from surface in UHV to surface in gas or liquid phase and fundamentals of X-ray spectroscopy Significance and challenges of studying surface of a catalyst in gaseous phase and instrumentation of ambient pressure X-ray photoelectron spectrometers Experimental methods of AP-XPS studies and difference in data analysis between AP-XPS and high vacuum XPS Ambient Pressure X-Ray Photoelectron Spectroscopy is an ideal resource for entry level researchers and students involved in x-ray photoelectron spectroscopy. Additionally, the te

关键词： 紫苏   三维荧光   小波包分解   Fisher判别分析   BP神经网络   支持向量机  

摘要： 为实现紫苏品种的快速鉴别，避免以次充好，选取四个品种的紫苏采集三维荧光数据，提出了一种基于小波包分解融合Fisher判别分析(Fisher Discriminant Analysis，FDA)的荧光数据特征选择策略，并实施了四种紫苏的有效鉴别。首先，对三维荧光数据进行预处理，采用Delaunay三角形内插值法去除瑞利散射和拉曼散射，以消除它们的不利影响；运用Savitzky-Golar（SG）卷积平滑对数据进行平滑处理，以减少噪声的干扰。同时，对三维荧光数据进行初步筛选，去除了荧光强度小于0.01 a.u.的发射波长。然后，对各激发波长对应的发射光谱进行3层sym4小波包分解，计算得到最低频段的小波包能量值，作为各激发波长光谱数据表征量。接着，再利用FDA对小波包能量进行判别分析，将其所包含的差异性信息进行融合，得到FDA生成的新变量，并选取累计判别能力达到99%的前3个FD变量作为不同品种差异性信息的表征变量，提出三维荧光数据的表征策略。最后，利用BP神经网络(Back Propagation Neural Network，BPNN)和支持向量机(Support Vector Machine，SVM)两种模式识别算法对表征变量进行分析，得到FDA+BPNN和FDA+SVM两种鉴别结果。FDA+BPNN的训练集正确率为97.5%，测试集正确率为95%；FDA+SVM的训练集和测试集的正确率均达到了98.33%。结果表明，三维荧光光谱技术结合小波包分解、FDA和SVM算法基本上能够实现紫苏品种的鉴别。这为后续有关紫苏的进一步检测研究（如某些有效成分的定量检测）奠定了基础。

摘要： Black hole X-ray binaries (XRBs) serve as essential astrophysical laboratories for in- vestigating the physics of the accretion flows and black holes. These systems, composed of a black hole and a companion star, exhibit a variety of spectral states, offering a unique opportunity to study the accretion dynamics on shorter timescales when compared to su- permassive black holes (SMBHs). In this work, we address the challenge of capturing the radiation processes within XRBs by presenting an implementation of a radiation prescrip- tion, which offers a lower computational cost compared to traditional radiative transfer codes, within the GPU-accelerated code H-AMR. Our approach incorporates a radiative so- lution that accounts for bremsstrahlung, synchrotron radiation, comptonized synchrotron, and coulomb collisions. Through extensive testing, we validate the functionality of our methodology. Our implementation provides a low-cost tool for investigating the properties and dynamics of black hole accretion flows in XRBs.

标准号: T/SSMTA 003-2023

摘要： Transcription factor Cbf11 belongs to the CSL protein family. The CSL protein family is well known for its function in Notch signalling pathway, however representatives in Notch- less fission yeast were discovered. Mga2 protein is a transcription regulator of triacylglycerol and glycerophospholipid metabolism. A crosstalk between Cbf11 and Mga2 was found. Cbf11 and Mga2 share target genes, and both are required for mitotic fidelity. This thesis aims to validate and characterize relationship between these transcription regulators. We show here that protein levels of Cbf11 and Mga2 change in response to presence of the other protein, as well as in response of nitrogen source. We also determine phylogenetic distribution of Cbf11 and Mga2 among Fungi, pointing to its connection. Using proteomic analysis of mga2 and cbf11 deletion strains we found that there is an overlap between proteins up/downregulated in these strains. Together, these results acknowledge crosstalk between Cbf11 and Mga2 proteins, bringing a novel connection between CSL protein family member and a functional analogue of mammalian SREBP-1 protein Mga2.

关键词： 晋城矿区   微观结构   GCMC   分子模拟   CO   -ECBM  

摘要： 为探究煤的孔径、芳香片层堆砌度、芳香片层延展度、气体温度、气体压力对CH4和CO2竞争吸附的影响，以晋城矿区3#煤为研究对象，对不同温度、不同压力、不同孔径、不同芳香片层堆砌度、不同芳香片层延展度下煤吸附CH4、CO2二元混合气体的过程进行研究。基于工业分析、X射线衍射实验对煤的微观结构进行测试与分析，采用巨正则系综蒙特卡洛(GCMC)方法对煤吸附混合气体的过程进行分子模拟，结果表明：气体压力增加有利于吸附，压力为5MPa时CO2的吸附量已接近饱和；温度增加会导致煤对CO2的最大吸附量和吸附热降低；孔径增大会导致煤对CH4的吸附量增大，孔径从1nm增加到2nm，CH4的吸附量增加最快；随芳香片层堆砌度的增加，煤吸附的气体分子数变化不明显，但单位质量煤对CO2的吸附量呈迅速下降趋势，对CH4的吸附量略有降低；随芳香片层延展度的增加，煤吸附的CH4分子数缓慢增加，吸附的CO2分子数快速增加，单位质量的煤对两种气体的吸附量变化不明显；从吸附量和吸附热两个角度来看，CO2在竞争吸附过程中均处于优势地位，因此向煤层注入CO2可有效驱替CH4。本文研究结果加强了分子层面对CH4、CO2二元混合气体吸附的认识，可为注CO2强化煤层气开采奠定理论基础。

摘要： Radio-Photo Luminescence (RPL) glasses are used as passive dosimeters, having a wide range of applications in different radiation fields, where low to high doses are absorbed. This work presents an experimental characterisation of FD-7, a commercial RPL glass dosimeter, irradiated with X-rays at different doses ranging from 0.3 kGy to 0.5 MGy. Investigation over such a broad range allows to enhance the understanding of RPL response in different dose level, out of their normal range of application up to 0.5 kGy. The purpose of this research is to achieve additional information on the response of FD-7 RPL glass dosimeters at high doses, to further their use in extreme high dose environment, especially targeting MGy range. The findings will be beneficial for the European Laboratory for Nuclear Research (CERN), where these dosimeters are used in environments in which such doses can be reached. In this study, a customized set-up has been developed, allowing the investigation of various relevant quantities, need to be measured in real-time. For instance, Radiation Induced Attenuation and transmittance response during irradiation and their recovery after irradiation are measured. It also allows to perform post-irradiation passive measurements. Parametric studies have been performed to assess the dependence of these quantities on the total absorbed dose and on the dose rate (ranging between 1.75 Gy/s and 0.175 Gy/s). Their kinetics during irradiation and recovery after irradiation are studied. Additionally, RPL signal evolution during irradiation with total absorbed dose up to 5 KGy at 1.036 Gy/s dose rate has been measured and reported, including settling of RPL signal to a constant intensity after irradiation. The RPL signal is normally used alone to determine the total absorbed dose, this technique being extensively used and considered as reliable up to approximately 0.3 kGy. For higher doses, a combination of both RPL signal and transmitted light is used to determine th