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101.
102.
Novatein is a thermoplastic polymer made from blood meal proteins, but it has rheological properties very different from commodity thermoplastics. Capillary rheometry revealed an apparent time dependent shear viscosity for Novatein, evident from a decreasing pressure drop over time, measured at constant shear rate. However, blending with polybutylene adipate-co-terephthalate (PBAT) reduced the time dependence for uncompatibilized blends and virtually eliminated time dependence for compatibilized blends containing 30 wt % PBAT. Novatein's extensional viscosity is three orders of magnitude more than its shear viscosity and explained the difficulty in sheet extrusion. In contrast, 30% compatibilized blends had an extensional viscosity similar to neat PBAT and was also the only blend that could be successfully sheet extruded. Although uncompatibilized blends at the same or lower PBAT content also had a lower extensional viscosity, they could not be sheet extruded and the difference was the 30% compatibilized blends had a fine PBAT phase structure (co-continuous in this case), which was sufficiently adhered to the Novatein phase. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47977. 相似文献
103.
T. Beechie H. Imaki J. Greene A. Wade H. Wu G. Pess P. Roni J. Kimball J. Stanford P. Kiffney N. Mantua 《河流研究与利用》2013,29(8):939-960
An important question for salmon restoration efforts in the western USA is ‘How should habitat restoration plans be altered to accommodate climate change effects on stream flow and temperature?’ We developed a decision support process for adapting salmon recovery plans that incorporates (1) local habitat factors limiting salmon recovery, (2) scenarios of climate change effects on stream flow and temperature, (3) the ability of restoration actions to ameliorate climate change effects, and (4) the ability of restoration actions to increase habitat diversity and salmon population resilience. To facilitate the use of this decision support framework, we mapped scenarios of future stream flow and temperature in the Pacific Northwest region and reviewed literature on habitat restoration actions to determine whether they ameliorate a climate change effect or increase life history diversity and salmon resilience. Under the climate change scenarios considered here, summer low flows decrease by 35–75% west of the Cascade Mountains, maximum monthly flows increase by 10–60% across most of the region, and stream temperatures increase between 2 and 6°C by 2070–2099. On the basis of our literature review, we found that restoring floodplain connectivity, restoring stream flow regimes, and re‐aggrading incised channels are most likely to ameliorate stream flow and temperature changes and increase habitat diversity and population resilience. By contrast, most restoration actions focused on in‐stream rehabilitation are unlikely to ameliorate climate change effects. Finally, we illustrate how the decision support process can be used to evaluate whether climate change should alter the types or priority of restoration actions in a salmon habitat restoration plan. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
104.
J. W. Radcliffe J. W. Loram J. M. Wade G. Wltschek J. L. Tallon 《Journal of Low Temperature Physics》1996,105(3-4):903-908
We have measured the magnetic field dependence of the electronic specific heat el (=Cel/T) of polycrystalline Tl2Ba2CuO6+ from 8 K to above Tc, for samples with Tc = 24 K to 72 K using a high resolution, differential technique. We find that in applied fields of up to 13 T the position of the specific heat jump does not shift significantly for any Tc. This is in strong disagreement with HC2(T) inferred from magnetoresistance experiments on the same compound, where the resistive transition is shifted down considerably by similar fields. However, there is a dramatic collapse of the specific heat anomaly height in field — signifying a loss in entropy around Tc — compensated by a corresponding increase in el at lower temperatures. The superconducting anomaly is almost completely suppressed in 13 T for the lowest Tc sample, compared to a reduction of 65 % for the sample with Tc = 72 K. We find simple vertical scaling of el(T) — n suggesting that the field forces a proportion of the superconductor into the normal state, while the remainder in the superconducting state is unaffected. 相似文献
105.
Badeau R.W. Bahar R.I. Bernstein D. Biro L.L. Bowhill W.J. Brown J.F. Case M.A. Castelino R.W. Cooper E.M. Delaney M.A. Deverell D.R. Edmonson J.H. Ellis J.J. Fischer T.C. Fox T.F. Gowan M.K. Gronowski P.E. Herrick W.V. Jain A.K. Meyer J.E. Miner D.G. Partovi H. Peng V. Preston R.P. Somanathan C. Stamm R.L. Thierauf S.C. Uhler G.M. Wade N.D. Wheeler W.R. 《Solid-State Circuits, IEEE Journal of》1992,27(11):1585-1598
A macropipelined CISC microprocessor was implemented in a 0.75-μm CMOS 3.3-V technology. The 1.3-million-transistor custom chip measures 1.62×1.46 cm2 and dissipates 16.3 W. The 100-MHz parts were benchmarked at 50 SPEC marks. The on-chip clocking system and several high-performance logic and circuit techniques are described. Macroinstruction handling, micropipeline management, and control store structures highlight the design architecture. The hierarchical array organization and fast tag comparison technique of the primary cache are discussed. Power estimation procedures are outlined, and the results are compared to measurements. Physical design and verification methods, and CAD tools are also described. After extensive functional verification efforts are described, chip and system test results are presented 相似文献
106.
Chlorophyll-a in the rivers of eastern England 总被引:5,自引:0,他引:5
Chlorophyll-a concentration variations are described for two major river basins in England, the Humber and the Thames and related to catchment characteristics and nutrient concentrations across a range of rural, agricultural and urban/industrial settings. For all the rivers there are strong seasonal variations, with concentrations peaking in the spring and summer time when biological activity is at its highest. However, there are large variations in the magnitude of the seasonal effects across the rivers. For the spring-summer low-flow periods, average concentrations of chlorophyll-a correlate with soluble reactive phosphorus (SRP). Chlorophyll-a is also correlated with particulate nitrogen (PN), organic carbon (POC) and suspended sediments. However, the strongest relationships are with catchment area and flow, where two straight line relationships are observed. The results indicate the importance of residence times for determining planktonic growth within the rivers. This is also indicated by the lack of chlorophyll-a response to lowering of SRP concentrations in several of the rivers in the area due to phosphorus stripping of effluents at major sewage treatment works. A key control on chlorophyll-a concentration may be the input of canal and reservoir waters during the growing period: this too relates to issues of residence times. However, there may well be a complex series of factors influencing residence time across the catchments due to features such as inhomogeneous flow within the catchments, a fractal distribution of stream channels that leads to a distribution of residence times and differences in planktonic inoculation sources. Industrial pollution on the Aire and Calder seems to have affected the relationship of chlorophyll-a with PN and POC. The results are discussed in relation to the Water Framework Directive. 相似文献
107.
Salman Azhar Wade A. CarltonDarren Olsen Irtishad Ahmad 《Automation in Construction》2011,20(2):217-224
Today, there is a high level of demand for sustainable buildings. The most important decisions regarding a building's sustainable features are made during the design and preconstruction stages. Leadership in Energy and Environmental Design (LEED®) is the most widely adopted sustainable building rating system in the United States. For projects pursuing LEED® certification, designers have to conduct in-depth sustainability analyses based on a building's form, materials, context, and mechanical-electrical-plumbing (MEP) systems. Since Building Information Modeling (BIM) allows for multi-disciplinary information to be superimposed within one model, it creates an opportunity to conduct these analyses accurately and efficiently as compared to the traditional methods. In this exploratory research, a case study was conducted on Salisbury University's Perdue School of Business building to demonstrate the use of BIM for sustainable design and the LEED® certification process. First, a conceptual framework was developed to establish the relationship between BIM-based sustainability analyses and the LEED® certification process. Next, the framework was validated via this case study. The results of this study indicate that documentation supporting LEED® credits may be directly or indirectly prepared using the results of BIM-based sustainability analyses software. This process could streamline the LEED® certification process and save substantial time and resources which would otherwise be required using traditional methods. 相似文献
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109.
As evidenced by the eclecticism of this collection of essays, the history of psychology is ripe with possibilities for additional research into the interplay of politics and public policy on the development of the discipline and its practice. After all, as this collection makes clear, a more complete rendering of the history of psychology must make sense of the profession’s longstanding immersion in politics and public policy—indeed, of its being as much a political and policymaking project as an intellectual one. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
110.
Vogel David L.; Wester Steven R.; Larson Lisa M.; Wade Nathaniel G. 《Canadian Metallurgical Quarterly》2006,37(4):398
Despite the presence of quality mental health care in many communities, people tend to avoid seeking help and wind up languishing in their problems unnecessarily. For the professional to better understand how to reach these individuals, an information-processing model is presented that examines the effects of people's interpretation of their environment and their symptoms on their decision to seek mental health services. Using the model as a guide, suggestions are presented for practitioners who wish to provide services to those who are in need of professional help, yet are hesitant to obtain it. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献