1,406 research outputs found
Microstrain in pyrope-grossular garnet solid solution at high pressure: a case study of Py(90)Gr(10) and Py(10)Gr(90) up to 15 GPa
No full textSingle-phase, well-sintered, translucent polycrystalline garnets with compositions of Py(90)Gr(10) and Py(10)Gr(90) were synthesized at 6 GPa and 1400 degrees C using a multi-anvil apparatus. X-ray diffraction (XRD) data for these garnet solid solutions were collected with both high-resolution synchrotron X-ray and standard laboratory X-ray sources. Analysis of the FWHM of the XRD peaks using Williamson-Hall plot yields microstrains around 0.12% for Py(90)Gr(10) and 0.09% for Py(10)Gr(90). The FWHM of Py(10)Gr(90) garnet as well as the derived microstrain remains constant up to 11 GPa, followed by a continuous increase to the experimental peak pressure 15 GPa caused by elastic strain in response to deviatoric/anisotropic stresses. The FWHM and microstrain for Py(90)Gr(10) remain constant to the measurement limit at 7 GPa. The microstrain of pyrope-grossular garnets exhibits a nonlinear dependence on composition, showing two peaks near Py(20)Gr(80) and Py(80)Gr(20), which may be associated with local structural heterogeneities arising from Mg and Ca substitution. Using a third-order Birch-Murnaghan equation of state, the bulk modulus is constrained to be Ie (0) = 171.8 +/- 2.1 GPa (with K-0(') fixed to 5.92) for Py(10)Gr(90) and Ie (0) = 174.3 +/- 2.5 GPa (with K-0(') fixed to 4.4) for Py(90)Gr(10), both of which are much larger than that for intermediate composition close to Py(50)Gr(50) but comparable to that for their corresponding end members. The relatively larger microstrain and higher bulk moduli for Py(10)Gr(90) and Py(90)Gr(10) garnets could be related to short-range ordering of Mg and Ca cations in garnet structure due to substitution, which results in different local environments for Mg and Ca cations along the pyrope-grossular solid solution.DOE/NNSA [DE-NA0002907]; NSF [EAR1524078]SCI(E)ARTICLE6377-3884
Synthesis, crystal structure and nonlinear optical properties of two novel linear cluster polymers {[MoOS3Cu3(CN)(py)3].0.5C6H6}n and [WOS3Cu3(CN)(py)4]n
No full textCluster polymers {[MoOS3Cu3(CN)(py)3]·0.5C6H6}n 1 and [WOS3Cu3(CN)(py)4]n 2 were synthesized by the reaction of (NH4)2MO2S2 (M = Mo, W) and CuCN with py. Their structures have been characterized by X-ray diffraction. Both of them show neutral nest-shaped structural units, and every structural unit forms two Cu1–N1–C1–Cu3 bridges with two other structural units leading to infinite one-dimensional polymers. In every unit cell of {[MoOS3Cu3(CN)(py)3]·0.5C6H6}n there are four [MoOS3Cu3(CN)(py)3] structural units and two benzene molecules, and the four structural units are from four independent linear polymer molecules which are parallel. In every unit cell of polymer 2, there are four [WOS3Cu3(CN)(py)4] structural units too, but they are only from two parallel linear polymer molecules. Polymer 1 shows good nonlinear optical (NLO) absorptive and NLO refractive properties, whereas strong NLO properties of polymer 2 are not observed
From appreciation to dwelling : on the evolution of Hong Kong's non-fiction nature writing = Cong shang wan dao qi ju : lun Xianggang fei xu gou zi ran shu xie zhi yan bian
No full textRecent scholarship on Hong Kong’s nature-oriented literature predominantly looks into fiction. This thesis examines non-fictional prose, so as to highlight the generic feature of nature writing, in which field experience, knowledge and emotions of the author are intertwined. It aims to fill the gap in literary ecocriticism and trace the evolving trajectory of Hong Kong’s nature writing since the 1930s. How do these texts reflect the interrelationship between humans, non-human beings and the environment? How do they interact with the environmental discourse in Hong Kong over time? In particular, this study focuses on three types of nature writing—travel accounts of the countryside, plant and animal writing, as well as pastoral writing. Borrowing the theoretical lens of “mobility” and “sense of place” from human geography, this thesis explicates how various mobilities in the texts alter human-nature relations and present the possibility of “nature as a place”. It first explores how different ways of walking shape the travelers’ perceptions towards the countryside. It then illustrates the influence of interactive dynamics between human and non-human beings on the imagination of a cohabiting place. Eventually, it elaborates how the author establishes a profound connection with the land through farming. Despite the distinctive development and internal heterogeneity of each type, the texts generally demonstrate a turn from the anthropocentric, urban identified topophilia to the nature-oriented topophilia. It shows humans gradually move beyond their experiences of leisure, stop manipulating nature, and (re-)learn to dwell with it in the Anthropocene.published_or_final_versionChineseMasterMaster of Philosoph
atomneb/AtomNeb-py: AtomNeb-py.0.3.0
No full textAtomNeb - Python Package for Atomic Data of Ionized Nebulae
AtomNeb is a database containing atomic data stored in FITS file format generated for for spectral analysis. The AtomNeb Python Package is equipped with several API functions developed in the Python language, which can be used to read atomic data from the AtomNeb FITS files. The API functions of the AtomNeb Python Package, together with the pyEQUIB Python Package, can be used to carry out plasma diagnostics and abundance analysis of spectra emitted from ionized nebulae.
Update Summary
Change data structures from pandas.DataFrame to NumPy
Add Chianti 9.0 atomic data
Citation
@article{Danehkar2020,
author = {{Danehkar}, Ashkbiz},
title = {AtomNeb Python Package, an addendum to AtomNeb: IDL Library for Atomic Data of Ionized Nebulae},
journal = {Journal of Open Source Software},
volume = {5},
number = {55},
pages = {2797},
year = {2020},
doi = {10.21105/joss.02797}
Photodegradation of pyrogenic dissolved organic matter (Py-DOM): a combined photon counting and distribution-based FT-ICR MS study
No full textQuantitative systematic studies are needed to elucidate the both short and long-term environmental implications of increasing pyrogenic dissolved organic matter (Py-DOM) inputs associated with projected increase in wildfire activity over the next century. Time-resolved fluorescence spectroscopy and Fourier transform ion cyclotron resonance were used to characterize extracts of unaltered and pyrolyzed wood and plant material. Upon pyrolysis, extracts shifted from a predominantly phenolic signature to a carboxylic-rich alicyclic configuration. Photodegradation of extracts was commensurate with solar energy exposure. The rate of photodegradation and the degradable fraction of DOM was component driven. Results of this study point to a disproportionate energy-induced response in components common to lignocellulose-derived DOM. Further studies are required to elucidate the mechanistic aspect of photodegradation of DOM, and Py-DOM as relates to energy input
atomneb/AtomNeb-py: AtomNeb-py.0.3.3
No full textAtomNeb - Python Package for Atomic Data of Ionized Nebulae
AtomNeb is a database containing atomic data stored in FITS file format generated for for spectral analysis. The AtomNeb Python Package is equipped with several API functions developed in the Python language, which can be used to read atomic data from the AtomNeb FITS files. The API functions of the AtomNeb Python Package, together with the pyEQUIB Python Package, can be used to carry out plasma diagnostics and abundance analysis of spectra emitted from ionized nebulae.
Update Summary
Add Jupyter Notebooks
Citation
@article{Danehkar2020,
author = {{Danehkar}, Ashkbiz},
title = {AtomNeb Python Package, an addendum to AtomNeb: IDL Library for Atomic Data of Ionized Nebulae},
journal = {Journal of Open Source Software},
volume = {5},
number = {55},
pages = {2797},
year = {2020},
doi = {10.21105/joss.02797}
Identification of 5,6-trans-epoxyeicosatrienoic acid in the phospholipids of red blood cells
No full textAs epoxyeicosatrienoic acids (EETs), particularly 11,12-EET, and the heme oxygenase/carbon monoxide (HO/CO) system share overlapping biological activities, we examined a possible link between 11,12-EET and HO activity in endothelial cells. Confocal microscopy analysis of immunostaining of HO-1 and HO-2 in cultured endothelial cells treated with 11,12-EET (1 microM) showed an increase in florescence of HO-1 protein in the various cellular compartments, but not of HO-2. Incubation of endothelial cells with 11,12-EET (1 microM) for 24 h increased the level of HO-1 protein by about three-fold. Similarly, incubation of endothelial cells with 8,9-EET and sodium nitroprussiate, a known inducer of HO-1, increased HO-1 protein without any effect on HO-2. Upregulation of HO-1 by 11,12-EET, as well as 8,9-EET, was associated with an increase in HO activity, which was inhibited by stannous mesoporphirin (10 microM). Incubation of rat aortas with 11,12-EET (1 microM for 60 min) increased HO activity. These findings identify a novel effect of EETs on endothelial HO-1 and indicate that the signaling pathway of EETs in endothelial cells is possibly via an increase in HO-1 expression and activity
In-plane spin reorientation transition in Co/Py bilayers grown epitaxially on vicinal Cu(001)
No full textCo/Py bilayers were grown epitaxially onto a vicinal Cu(001) substrate with the atomic steps parallel to the [110] crystalline axis. We show that the magnetization in vicinal Cu/Co/Py/Cu(001) undergoes an in plane spin reorientation transition (SRT) from perpendicular to parallel direction of the steps as the Co film thickness increases. By performing Rotation Magneto-Optic Kerr Effect (ROTMOKE) measurement as a function of both the Py and the Co film thicknesses, we show that the observed in-plane SRT results from a competition between the step-induced uniaxial anisotropies in the Py and Co films that favor the Py and Co magnetizations perpendicular and parallel to the atomic steps, respectively. Step decoration experiment further shows that the uniaxial anisotropy originates from the step edges of the vicinal surface. (C) 2016 Elsevier B.V. All rights reserved.National Science Foundation NRF through the Global Research Laboratory project of Korea [DMR-1504568]; China Scholarship Council; National Natural Science Foundation of China [51331006]SCI(E)EIARTICLE193-19840
- …
