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31.
Zachary Taie Gertrude Villaverde Jennifer Speaks Morris Zoe Lavrich Anna Chittum Keith White Christopher Hagen 《International Journal of Hydrogen Energy》2021,46(5):3365-3378
To determine if a power-to-gas pilot-scale plant would be possible in Oregon, a feasibility study was conducted that assessed the technical, political, economic, environmental, safety, and policy aspects of a potential project in the region. The results of this study were submitted as part of Oregon State University – Cascades' entry to the Hydrogen Education Foundation's 2018 student design competition. The Pacific Northwest has a need for long term energy storage (seasonal energy shifting) due to seasonally available low-priced, low-carbon electricity. There appears to be the political motivation and the technical feasibility to install a demonstration-scale power-to-gas plant in the region to assess the technical and economic performance of the system when exposed to real-world boundary conditions. However, preliminary economic analyses show the system will be challenged by low capacity factor operation resulting in a levelized cost of hydrogen of $121.81/kgH2 when only using otherwise curtailed electricity, or $8.84/kgH2 when running continuously for 6 months per annum. To fund a pilot scale plant a renewable gas development surcharge of $0.18/therm is proposed as a way for willing customers to support the decarbonization mission. There is precedent within the utility for such an incentive, indicating that it would be approved by the utility commission and could be a viable path forward for a pilot-scale plant. 相似文献
32.
Diana M. Ceballos Jessica Craig Xianqiang Fu Chunrong Jia David Chambers MyDzung T. Chu Alai T. Fernandez Victoria Fruh Zoe E. Petropoulos Joseph G. Allen Jose Vallarino Lydia Thornburg Thomas F. Webster 《Indoor air》2019,29(4):539-550
Nail technicians are exposed to volatile organic compounds (VOCs) from nail products, but no studies have previously measured VOC biomarkers for these workers. This study of 10 nail technicians aimed to identify VOCs in nail salons and explore relationships between air concentrations and biomarkers. Personal and area air samples were collected using thermal desorption tubes during a work shift and analyzed using gas chromatography/mass spectrometry (GC/MS) for 71 VOCs. Whole blood samples were collected pre‐shift and post‐shift, and analyzed using GC/MS for 43 VOCs. Ventilation rates were determined using continuous CO2 measurements. Predominant air VOC levels were ethyl methacrylate (median 240 µg/m3), methyl methacrylate (median 205 µg/m3), toluene (median 100 µg/m3), and ethyl acetate (median 639 µg/m3). Blood levels were significantly higher post‐shift than pre‐shift for toluene (median pre‐shift 0.158 µg/L and post‐shift 0.360 µg/L) and ethyl acetate (median pre‐shift <0.158 µg/L and post‐shift 0.510 µg/L); methacrylates were not measured in blood because of their instability. Based on VOCs measured in these seven nail salons, we estimated that emissions from Greater Boston area nail salons may contribute to ambient VOCs. Ventilation rates did not always meet the ASHRAE guideline for nail salons. There is a need for changes in nail product formulation and better ventilation to reduce VOC occupational exposures. 相似文献
33.
Discusses the contributions and limitations of D. G. Dutton's and J. J. Browning's (1988) videotape studies of wife assault. These studies demonstrate that batterers are most sensitive to scenes of emotional abandonment. It is suggested, however, that these findings should be interpreted with an awareness that the videotape manipulations are not necessarily representative of the whole class of possible stimulus manipulations. More confidence in the conclusions may be derived from replication of the intimacy findings across a range of topics. Improved manipulation of the dominance variable is also advised. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
South Africa has a decade of experience designing and implementing biodiversity offsets. In the absence of explicit national policy on biodiversity offsets, the country has relied on existing legal provisions in environmental law as the basis for offset requirements, supported by provincial guidelines. South Africa’s periodic national biodiversity surveys provide scientifically rigorous quantification and mapping for individual ecosystems and finer scale surveys identify biodiversity priority areas, primed as ‘offset receiving areas’. Yet despite enabling factors the use of offsets has frequently been inadequate to deliver intended biodiversity outcomes. Challenges include: (a) the absence of national policy to drive and shape offset implementation; (b) insufficient capacity to evaluate, design and implement offsets; (c) inconsistent decision-making; (d) problems establishing sustainable financing mechanisms; and (e) inadequate enforcement and monitoring, linked to poor drafting of licencing conditions and/or insufficient capacity to monitor implementation. South Africa’s experience provides valuable insights into the challenges and potential solutions for making offsets work for biodiversity conservation and offers important lessons for the development and implementation of biodiversity offsetting in other developing countries. 相似文献
35.
Peter A. Novak Charlie A. Fairfield Mike Miloshis Zoe C. Knight Robert Lindsay Alison J. King 《河流研究与利用》2021,37(1):3-16
Macrotidal tropical rivers are dynamic systems where wet‐season floods and tidal flows cause significant riverbank erosion and sediment transport. This study aimed to explore patterns of riverbank erosion and deposition in a large, tropical, macrotidal river in Northern Australia; the Daly River. In particular, we aimed to determine if recreational boat use was impacting bank erosion in this dynamic river. Erosion pins were installed at multiple levels on both banks at 10 sites along a 34 km reach of the river. Measurements were made every four to six weeks during the low water dry season, and opportunistically during the wet season (flooding period) and seasonal transition periods. A bank geotechnical assessment, riverbed cross‐sections and site bathymetry were undertaken. Whilst the wet season was a period of substantial erosion (mean rate of 0.64 mm day?1), the highest mean erosion rate (3.6 mm day?1) was observed in the early dry season (April to May), a period of stabilizing water levels but greatest boat traffic. Bank erosion at this time was measured on both sides of the river and the inside of meander bends, which is atypical of normal riverine bank erosion patterns, and indicative of erosion due to boat wash. As the dry season progressed, significant spatial differences in erosion rates were evident, where erosion was observed at sites upstream of a large shallow sand bar, while sites downstream from the sand bar gained material through the deposition of tidally transported sediment. This study highlights the importance of understanding the significance and interaction of various erosive factors in tropical tidal rivers and has demonstrated that boat wash may be an important contributor to dry season bank erosion in these systems. We encourage management agencies to consider the role of boats in any future river management program in these systems. 相似文献
36.
Spontaneously adsorbed monolayers of [Co(ttp-CH2-SH)2](PF6)2 have been formed on platinum microelectrodes by exposure to micromolar solutions of the complex in 0.1 M TBABF4 in acetonitrile, ttp-CH2-SH is 4′-(p-(thiolmethyl)-phenyl)-2,2′:6′,2″-terpyridine. Resonance Raman spectroscopy on roughened polycrystalline platinum macro electrodes show that the molecule undergoes adsorption through the sulphur atom onto the platinum surface. The monolayers show reversible and well defined cyclic voltammetry when switched between Co2+ and Co3+ forms, with a peak to peak splitting of 0.040 ± 0.005 V up to 200 V s−1 and an FWHM of 0.138 ± 0.010 V. Adsorption is irreversible leading to the maximum surface coverage, 6.3 ± 0.3 × 10−11 mol cm−2 for 2.5 ≤ [Co(ttp-CH2-SH)2] ≤ 10 μM. The rate of monolayer formation appears to be controlled not by mass transport or interfacial binding but by surface diffusion of the complex. The surface diffusion coefficient is 5.5 ± 1.1 × 10−7 cm2 s−1 indicating that prior to formation of an equilibrated monolayer, the adsorbates have significant mobility on the surface. The electron transfer process across the monolayer-electrode interface has been probed by high speed chronoamperometry and the standard heterogeneous electron transfer rate constant, k°, is approximately 3.06 ± 0.03 × 104 s−1. The reorganization energy is at least 18.5 kJ mol−1. 相似文献
37.
Zoe A.D. Lethbridge Richard I. Walton Arnaud S.H. Marmier Christopher W. Smith Kenneth E. Evans 《Acta Materialia》2010,58(19):6444-6451
The relationship between elastic anisotropy and extreme Poisson’s ratio behaviour (either positive or negative) in single-crystalline materials has been investigated using experimentally determined single-crystal elastic constants for a wide range of solid materials. This makes use of a recently proposed elastic anisotropy index that is applicable to all crystal symmetries. For many real materials we find a striking correlation between the value of the elastic anisotropy index and the magnitudes of maximum and minimum Poisson’s ratios this is independent of crystal symmetry. This structure–property relationship provides new examples of auxetics and shows that negative Poisson’s ratios are actually not uncommon among many classes of inorganic (and organic) materials, including elemental metals, alloys, ionic solids, molecular solids and giant covalent networks. 相似文献
38.
Thomas A. Neumann Mary R. Albert Chandler Engel Zoe Courville Frank Perron 《International Journal of Heat and Mass Transfer》2009,52(1-2):309-315
Sublimation of snow is a fundamental process that affects the crystal structure of snow, and is important for ice core interpretation, remote sensing, snow hydrology and chemical processes in snow. Prior investigations have inferred the sublimation rate from energy, isotopic, or mass-balance calculations using field data. Consequently, these studies were unable to control many of the environmental parameters which determine sublimation rate (e.g. temperature, relative humidity, snow microstructure). We present sublimation rate measurements on snow samples in the laboratory, where we have controlled many of these parameters simultaneously. Results show that the air stream exiting the snow sample is typically saturated under a wide range of sample temperature and air-flow rate, within measurement precision. This result supports theoretical work on single ice grains which found that there is no energy barrier to be overcome during sublimation, and suggests that snow sublimation is limited by vapor diffusion into pore spaces, rather than sublimation at crystal faces. Undersaturation may be possible in large pore spaces (i.e. surface- or depth-hoar layers) with relatively high air-flow rates. We use these data to place bounds on the mass-transfer coefficient for snow as a linear function of Reynolds number, and find that hm = 0.566 Re + 0.075. 相似文献
39.
建筑师操刀室内设计,越来越多地个性设计发生在时尚门店的身上。这种建筑和时装的结合,是时尚品牌帝国提升自己形象的得意之举。无论是韩国庆熙宫的白色装置建筑,还是美国第五大道上舞动的楼梯设计,都让人赞叹。 相似文献
40.
Stevenson Richard J.; Miller Laurie A.; Thayer Zoe C. 《Canadian Metallurgical Quarterly》2008,34(5):1183
Certain odors have tastelike qualities when sniffed. To the extent that these qualities are akin to real taste experiences, impairment in perception of odor-induced tastes should be accompanied by taste impairment, and vice versa. Twelve patients were selected with possible odor-induced taste impairments or general taste impairments via a screening test, along with a further 6 patients with a probable taste impairment (insular lesion). These 18 patients, along with 19 normal controls, completed a battery of odor, taste, visual control, and neuropsychological tests to assess impairments in odor-induced taste perception and general taste perception. Four patients had an odor-induced taste impairment and were also impaired on taste perception. A further analysis, using regression on the whole sample, indicated that taste impairments were associated with odor-induced taste abnormalities independent of other predictors. This pattern also held for the patient group alone. The insular patients also exhibited both taste and odor-induced taste impairments. This study is the first to demonstrate a relationship between impaired taste perception and the perception of odor-induced tastes and suggests that both may rely on certain common neural substrates. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献