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151.
The objective of this study was to identify the major electricity and water-consuming components of a pasture-based automatic milking (AM) system and to establish the daily and seasonal consumption trends. Electricity and water meters were installed on 7 seasonal calving pasture-based AM farms across Ireland. Electricity-consuming processes and equipment that were metered for consumption included milk cooling components, air compressors, AM unit(s), auxiliary water heaters, water pumps, lights, sockets, automatic manure scrapers, and so on. On-farm direct water-consuming processes and equipment were metered and included AM unit(s), auxiliary water heaters, tubular coolers, wash-down water pumps, livestock drinking water supply, and miscellaneous water taps. Data were collected and analyzed for the 12-mo period of 2015. The average AM farm examined had 114 cows, milking with 1.85 robots, performing a total of 105 milkings/AM unit per day. Total electricity consumption and costs were 62.6 Wh/L of milk produced and 0.91 cents/L, respectively. Milking (vacuum and milk pumping, within-AM unit water heating) had the largest electrical consumption at 33%, followed by air compressing (26%), milk cooling (18%), auxiliary water heating (8%), water pumping (4%), and other electricity-consuming processes (11%). Electricity costs followed a similar trend to that of consumption, with the milking process and water pumping accounting for the highest and lowest cost, respectively. The pattern of daily electricity consumption was similar across the lactation periods, with peak consumption occurring at 0100, 0800, and between 1300 and 1600 h. The trends in seasonal electricity consumption followed the seasonal milk production curve. Total water consumption was 3.7 L of water/L of milk produced. Water consumption associated with the dairy herd at the milking shed represented 42% of total water consumed on the farm. Daily water consumption trends indicated consumption to be lowest in the early morning period (0300–0600 h), followed by spikes in consumption between 1100 and 1400 h. Seasonal water trends followed the seasonal milk production curve, except for the month of May, when water consumption was reduced due to above-average rainfall. This study provides a useful insight into the consumption of electricity and water on a pasture-based AM farms, while also facilitating the development of future strategies and technologies likely to increase the sustainability of AM systems. 相似文献
152.
A new technique for the observation and interpretation of concentration profiles in diffusion layers at membrane-solution interfaces was developed. The concentration profiles in dilute (0·01N) KCl solutions near an ion-exchange membrane were observed in a modified O'Brien-type wedge laser interferometer while electric current (1·15 and 2·3 mA cm?2) passed through the solution (25°C). After current reversal, following prepolarization periods of 5–60 s, a concentration minimum develops. The image of this minimum in relation to the membrane surface is not subject to optical deflection and can therefore be accurately determined. From its trajectory, the salt concentration at the membrane surface at the time of current reversal was determined. It was found that as this concentration dropped to the order of 10?3–10?4M (“critical concentration”) significant deviations occurred between observed trajectories and those computed from a theory based on the Nernst-Planck equations. These deviations are believed to be caused by substantial migration of H+ and OH?. While these measurements indicate the order of magnitude of the critical concentration, additional measurements are necessary for quantitative determination of this concentration under different physicochemical and hydrodynamic conditions. 相似文献
153.
William G. O’Brien Harvey J. Jensen Robert N. Benedict Renato G. Bautista 《Metallurgical and Materials Transactions B》1976,7(4):671-677
The decomposition equilibria of platinum dichloride have been found to consist of two decomposition steps, with chlorine molecules
being the vapor species for both steps. An intermediate metastable PtCl solid is formed in the first step in addition to platinum
metal and chlorine molecules. The platinum dichloride decomposes incongruently, the stepwise decomposition being PtCl2 → PtCl → Pt. The PtCl2 decomposition reactions consist of PtCl2(s) = PtCl (metastables) + 1/2 Cl2
(g) and PtCl2(s) = Pt(s) + Cl2
(g). The sum of the third lawΔH
D, 298 K for the above two reactions is 214.637 ± 1.963 kJ/mole, in very good agreement with the second law ΔHD, 298 K = 215.107 ± 13.062 kJ/mole. The second decomposition step is given by the reaction 2PtCl (metastables) = 2Pt(s) + Cl2
(g) with a third law ΔHD, 298 K = 127.356 ± 0.791 kJ/mole, in excellent agreement with the second law ΔHD, 298 K = 127.509 ± 6.154 kJ/mole. The calculated heat of formation of PtCl2 is -139 ± 2 kJ/mole and that of PtCl is -63 ± 1 kJ/mole.
Formerly Graduate Assistant.
Formerly Undergraduate Research Helper, 相似文献
154.
155.
Florian ‘Floyd’ Mueller Gunnar Stevens Alex Thorogood Shannon O’Brien Volker Wulf 《Personal and Ubiquitous Computing》2007,11(8):633-645
Sport is a domain full of movement-based interactions. These interactions typically have positive health effects as well as
an impact on social bonding. We have investigated ways in which computer augmented devices can lead to new sport experiences
and explored opportunities to combine physical activities with remote social bonding. Three prototypes have been implemented
which showcase movement-based interaction in sports. “Breakout for Two” allows geographically distant users to play a physically
exhausting ball game together. “FlyGuy” gives users a hang-glide experience controllable through body movement. “Push’N’Pull”
uses isometric exercise equipment over a network to encourage users to complete a cooperative game whilst performing intense
muscular actions. A comparison of these applications shows that such movement-based interaction in a networked environment
allows players in different locations to achieve a work out and also to socialize. Based on these projects, we conclude with
practical design implications for future Exertion Interfaces. 相似文献
156.
Hinnant J. Benjamin; O’Brien Marion; Ghazarian Sharon R. 《Canadian Metallurgical Quarterly》2009,101(3):662
There is relatively little research on the role of teacher expectations in the early school years or the importance of teacher expectations as a predictor of future academic achievement. The current study investigated these issues in the reading and mathematic domains for young children. Data from nearly 1,000 children and families at 1st, 3rd, and 5th grades were included. Child sex and social skills emerged as consistent predictors of teacher expectations of reading and, to a lesser extent, math ability. In predicting actual future academic achievement, results showed that teacher expectations were differentially related to achievement in reading and math. There was no evidence that teacher expectations accumulate but some evidence that they remain durable over time for math achievement. In addition, teacher expectations were more strongly related to later achievement for groups of children who might be considered to be at risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
157.
This paper presents a comparative analysis of three different infrastructure assessment tools currently used by the U.S. Army’s combat engineer small units (squad, platoon, company). The infrastructure assessment tools included one pen and paper checklist and two software-based tools based on specialized handheld hardware for data collection in combat conditions. Evaluation was conducted using macroergonomic and applied cognitive task analysis methods with soldiers of varying levels of infrastructure assessment expertise. Each assessment method was evaluated based on performance (time, errors, and accuracy) and usability (ergonomic and cognitive challenges). We found that soldiers documented more accurate data using handheld digital devices instead of pen-and-paper assessment forms, but there was little difference in time between the methods. Contrary to initial expectation, we also found that most soldiers prefer a slightly more difficult to use handheld assessment device with customized checklists rather than an easier to use, less restrictive device. Critiques developed by this research can be used to improve engineering and construction organizations as well as add to our design guidelines for portable infrastructure assessment tools and methods. 相似文献
158.
159.
Sukhomlinov Dmitry Klemettinen Lassi O’Brien Hugh Taskinen Pekka Jokilaakso Ari 《Metallurgical and Materials Transactions B》2019,50(6):2723-2732
Metallurgical and Materials Transactions B - The distributions of Ga, In, Sn, and Te between copper-iron mattes and silica-saturated iron silicate slags over a wide range of matte grades 55 to 75... 相似文献
160.
Carlotta Bon Ting-Rong Chern Elena Cichero Terrence E. OBrien Stefano Gustincich Raul R. Gainetdinov Stefano Espinoza 《International journal of molecular sciences》2022,23(6)
Trace amine-associated receptor 5 (TAAR5) is a G protein-coupled receptor that belongs to the TAARs family (TAAR1-TAAR9). TAAR5 is expressed in the olfactory epithelium and is responsible for sensing 3-methylamine (TMA). However, recent studies showed that TAAR5 is also expressed in the limbic brain regions and is involved in the regulation of emotional behaviour and adult neurogenesis, suggesting that TAAR5 antagonism may represent a novel therapeutic strategy for anxiety and depression. We used the AtomNet® model, the first deep learning neural network for structure-based drug discovery, to identify putative TAAR5 ligands and tested them in an in vitro BRET assay. We found two mTAAR5 antagonists with low to submicromolar activity that are able to inhibit the cAMP production induced by TMA. Moreover, these two compounds also inhibited the mTAAR5 downstream signalling, such as the phosphorylation of CREB and ERK. These two hits exhibit drug-like properties and could be used to further develop more potent TAAR5 ligands with putative anxiolytic and antidepressant activity. 相似文献