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21.
Scientific meetings and conferences are a part of the scientific process, and can facilitate collaboration, idea-sharing, and harmonization of research and management. The success of a conference can be measured using many criteria, including consistency and reoccurrence of the meetings, credibility by participation of reputable professionals, and attendance by a diverse community. In the interest of increasing the success of large-lake, freshwater science, policy, and management, this comment focuses on two recent conferences attended by the authors: the 60th annual meeting of the International Association for Great Lakes Research, in Detroit, U.S.A., and the African Great Lakes Conference, in Entebbe, Uganda. By our measures of success, we suggest that to make a larger impact on research, policy, and management of global, large, freshwater lakes that each conference can improve, either through greater diversity of experts from the global freshwater research community, or by consistently reoccurring on a regular basis. 相似文献
22.
Robert Gracie Ted Belytschko 《International journal for numerical methods in engineering》2009,78(3):354-378
A method for the modeling of dislocations and cracks by atomistic/continuum models is described. The methodology combines the extended finite element method with the bridging domain method (BDM). The former is used to model crack surfaces and slip planes in the continuum, whereas the BDM is used to link the atomistic models with the continuum. The BDM is an overlapping domain decomposition method in which the atomistic and continuum energies are blended so that their contributions decay to their boundaries on the overlapping subdomain. Compatibility between the continua and atomistic domains is enforced by a continuous Lagrange multiplier field. The methodology allows for simulations with atomistic resolution near crack fronts and dislocation cores while retaining a continuum model in the remaining part of the domain and so a large reduction in the number of atoms is possible. It is applied to the modeling of cracks and dislocations in graphene sheets. Energies and energy distributions compare very well with direct numerical simulations by strictly atomistic models. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
23.
正Ground control is the science of studying and controlling the behavior of rock strata in response to mining operations.Ground-control-related research has seen significant advancements over the last 40 years, and these accomplishments are well documented in the proceedings of the annual International Conference on Ground Control in Mining (ICGCM)[1]. 相似文献
24.
K. Lee Matheson Ted P. Matson Kang Yang 《Journal of the American Oil Chemists' Society》1986,63(3):365-370
A peaked ethylene oxide distribution alcohol ethoxylate can be produced using new catalyst systems. The mechanism of ethoxylation
is discussed. Such Novel™ ethoxylates are markedly different from a conventional ethoxylate in physical properties and performance
characteristics. Performance and formulation studies show several advantages for the peaked distribution in typical household
product formulations.
Presented at the AOCS meeting in Dallas, May 1984.
Deceased. 相似文献
25.
Phenyl isomer distributions, within current commercial limits of HF and A1C13 linear alkylbenzene sulfonates (LAS), have little effect on dishwashing performance in light-duty liquids (LDL), detergency performance in heavy-duty powders (HDP), and interfacial tension value. The most important factor in determining performance differences among commercial LAS samples is carbon chain homolog distribution. Both HF and A1C13 LAS perform equally well and can be used interchangeably in high-performance products. The optimum for foam stability in light-duty liquids shifts towards shorter alkyl chain length as water hardness increases. At 0 ppm water hardness the optimum occurs at C13: at 50–150 ppm the optimum moves to C11 and C12; and above 150 ppm the optimum shifts to include C10, C11 and C,12. The detergency performance optimum range in a phosphate built heavy-duty powder at 50 and 150 ppm water hardness includes the C12, C13 and C14 alkyl chain lengths. In a nonphosphate built powder the optimum is similar at 50 ppm hardness to that of a phosphate built powder, but shifts at 150 ppm hardness to include C11, C12 and C13. 相似文献
26.
Ted Belytschko 《International journal for numerical methods in engineering》2009,77(8):1051-1051
27.
Identification, characterization, and physiological actions of factor H as an adrenomedullin binding protein present in human plasma 总被引:4,自引:0,他引:4
A recently discovered adrenomedullin binding protein has been characterized as complement factor H, an important regulator of the complement cascade. This review will describe the evidence that led to the identification of factor H as an adrenomedullin binding protein and will address the implications that such binding has in the radioimmunoassay of AM in plasma. We will also describe the possible physiological implications of AM binding: namely, factor H suppresses the antimicrobial activity of AM, enhances AM-mediated induction of cyclic-AMP in rat fibroblasts, and augments the AM-mediated growth of a human cancer cell line. These initial studies suggest that factor H may be an important factor in the regulation of AM physiology. The elucidation of the mechanisms that modulate AM activity will be necessary for the understanding of the role of AM in normal and pathological conditions. 相似文献
28.
A computer simulation of a section of the interior region of a liquid chromatographic column is performed. The detailed fluid flow profile is provided from a microscopic calculation of low Reynolds number flow through a random packed bed of nonporous spherical particles. The fluid mechanical calculations are performed on a parallel processor computer utilizing the lattice Boltzmann technique. Convection, diffusion, and retention in this flow field are calculated using a stochastic-based algorithm. This computational scheme provides for the ability to reproduce the essential dynamics of the chromatographic process from the fundamental considerations of particle geometry, particle size, flow velocity, solute diffusion coefficient, and solute retention parameters when retention is utilized. The simulation data are fit to semiempirical models. The best agreement is found for the "coupling" model of Giddings and the four-parameter Knox model. These models are verified over a wide range of particle sizes and flow velocities at both low and high velocity. The simulations appear to capture the essential dynamics of the chromatographic flow process for non-dimensional flow velocities (Péclet number) less than 500. Since the same packing geometry is utilized for different particle size studies, the interpretation of the parameter estimates from these models can be extended to the physical column model. The simulations reported here agree very well with a number of experiments reported previously. 相似文献
29.
A prototype, all-sky flux mapper has been developed at the Solar Energy Research Institute (SERI). The flux mapper is a video system which provides a rapid, real time processing of daylightning luminance data. The system uses an orthographic-projection fish-eye lens to project the entire image of a 180° field onto a vidicon target. The signal is then digitized and may be plotted as equal brightness comtours or recorded on tape for later analysis. The system has great potential for use in delineating illuminance distribution of the sky and of interior spaces. 相似文献
30.
Three experiments were carried out to determine whether there is a lag in predicting surprise relative to false belief. All 3 experiments used "backwards reasoning" tasks. The findings were that ( a ) there is a lag in predicting surprise relative to false belief, ( b ) by 5 or 6 years of age children claim that one will be surprised when they gain knowledge of that which they were previously ignorant or when they discover that they had previously held a false belief, ( c ) by 7 to 9 years of age they understand that surprise will more likely result from false beliefs rather than mere ignorance, and ( d ) children's difficulty understanding surprise as specifically belief-based does not likely stem from information processing limitations. It is argued that the lag likely results because children must build a new concept of surprise ( e.g., from desire- to belief-based ) . (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献