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971.
Superstructures composed of diblock copolymer micelles and inorganic nanoparticles are quite interesting because the specific arrangement of inorganic nanoparticles within the micellar structure can reveal interesting opportunities in many field of science. In this perspective, we report a simple method to produce clustered assembly of Au nanoparticles in the micelles in attempt to induce plasmonic coupling among multiple Au nanoparticles in the assembled structures. Here, we utilized polystyrene‐block‐poly(acrylic acid), PS‐PAA, micelles containing single Au nanoparticle in the core (Au@PS‐PAA micelles) as building materials to initiate next‐level assembling process. In particular, the addition of HCl to the solution of Au@PS‐PAA micelles affected the overall equilibrium condition as well as kinetic process in the micellar solution. As a result, individual Au@PS‐PAA micelles could be merged together to form more large micelles with inclusion of multiple nanoparticles in the core, the process of which was accompanied with plasmonic coupling of Au nanoparticles. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44693. 相似文献
972.
Dynamic analysis and open‐loop start‐up of an integrated radiant syngas cooler and steam methane reformer 下载免费PDF全文
Jaffer H. Ghouse Dominik Seepersad Thomas A. Adams II 《American Institute of Chemical Engineers》2017,63(5):1602-1619
The transient performance of an integrated radiant syngas cooler (RSC) of an entrained‐bed gasifier and steam methane reformer (SMR) is investigated. Base‐case designs using either co‐current or counter‐current configurations are subjected to operating transients to evaluate the feasibility to transition to new steady states. Each system, under open loop, is subjected to changes in key variables of the SMR feed on the tube side and disturbances to variables of the coal‐derived syngas on the RSC side to determine the dynamics and stability of the integrated system. The results indicate that the co‐current configuration is flexible to move to new operating steady states and more safe than the counter‐current configuration, although it provides less cooling and has poorer methane conversion. The variables likely to violate the design limit in the event of a disturbance are identified. A start‐up procedure is also established based on industrial practices employed for entrained‐bed gasifiers and methane reformers. © 2016 American Institute of Chemical Engineers AIChE J, 63: 1602–1619, 2017 相似文献
973.
A review of Chemical Oxygen Iodine Laser (COIL) chemistry, physics, and technology is presented. Individual COIL components are discussed in relation to the COIL heuristic equation, which predicts COIL performance based on well-known, measurable, device performance parameters. Topics include singlet oxygen generators (SOGs), supersonic nozzle designs, I 2 mixing, and I 2 dissociation. In addition, a brief summary of the recently invented All Gas-phase Iodine Laser (AGIL) is given, where the I*(2P½) → I(2P3/2) inversion was generated by the NCl(a1 δ) + I(2P 3/2) energy transfer reaction. 相似文献
974.
Estimation of plasma parameters inside air bubbles including the electric field was conducted on the basis of experimental data on the hydrodynamic luminescence spectrum. 相似文献
975.
976.
Frederick J. Passman George L. Egger II Sarah Hallahan Brent W. Skinner Mark Deschepper 《摩擦学汇刊》2013,56(6):788-792
Adenosine triphosphate (ATP) assays have been used to quantify bioburdens (biomass) in low-organic-compound-content fluids (freshwater, seawater, cooling tower water, and similar fluids) since the early 1950s. The original methodology was labor intensive and required considerable laboratory skill. Over the past half-century, the protocol has been simplified substantially, but until recently, chemical interferences made it impractical to use the ATP test in metalworking fluids (MWF). This article presents precision and bias statistics for a new test protocol for ATP in emulsifiable oil, semisynthetic and synthetic MWF at end-use dilutions. Additionally it presents the results of field tests in which ATP data are compared with other MWF condition monitoring data. The field evaluation demonstrates the applicability of the new protocol to MWF bioburden condition monitoring. 相似文献
977.
978.
LaDage Lara D.; Roth Timothy C. II; Fox Rebecca A.; Pravosudov Vladimir V. 《Canadian Metallurgical Quarterly》2009,123(2):284
The complexity of an animal's physical environment is known to affect the hippocampus. Captivity may affect hippocampal anatomy and this may be attributable to the limited opportunities for memory-based experiences. This has tangential support, in that differential demands on memory can mediate changes in the hippocampus. What remains unclear is whether captivity directly affects hippocampal architecture and whether providing memory-based experiences in captivity can maintain hippocampal attributes comparable to wild-caught conspecifics. Using food-caching mountain chickadees (Poecile gambeli), we found that wild-caught individuals had larger hippocampal volumes relative to the rest of the telencephalon than captive birds with or without memory-based food-caching experiences, whereas there were no differences in neuron numbers or telencephalon volume. Also, there were no significant differences in relative hippocampal volume or neuron numbers between the captive birds with or without memory-based experiences. Our results demonstrate that captivity reduces hippocampal volume relative to the remainder of the telencephalon, but not at the expense of neuron numbers. Further, memory-based experiences in captivity may not be sufficient to maintain hippocampal volume comparable to wild-caught counterparts. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
979.
L.N. Dinh J.M. Haschke C.K. Saw P.G. Allen W. McLean II 《Journal of Nuclear Materials》2011,408(2):171-175
The role of cubic Pu2O3 in the corrosion of PuO2-coated Pu by H2 was investigated. Experiments were conducted to demonstrate that nucleation of hydriding is promoted by formation of Pu2O3 sites in the oxide layer. The nucleation mechanism based on diffusion of hydrogen through the PuO2 layer was evaluated and an alternative mechanism based on formation of catalytic Pu2O3 sites via the Pu-PuO2 reaction is proposed. The possibility of active participation of other impurities and inclusions in the dioxide is also discussed. 相似文献
980.
Daniel J. Kubek Vincent H. Gattone II Matthew R. Allen 《Microscopy research and technique》2010,73(3):182-186
Osteocytes are the most abundant of the bone cells. Each osteocyte is contained within its own lacuna and connected to adjacent osteocytes via fillipodial processes, which form an intricate network of canaliculi within the matrix. Studying this intricate network of cells and their processes is difficult, because it exists embedded within a densely mineralized matrix. Scanning electron microscopy (SEM) has been shown to be a useful tool for visualizing this cellular network, yet the techniques involved for preparing specimens has not been systematically explored. The goal of this study was to investigate how variations in acid‐etching, both etching media and etching duration, affect SEM‐based visualization of the osteocyte lacunar–canalicular network. Bone samples were embedded in plastic and then acid etched in either 9% (10, 20, 40, and 60 s durations) or 37% (5, 10, and 15 s) phosphoric acid. Specimens were imaged using SEM, and qualitative evaluation of the lacunar–canalicular network was undertaken. Our findings show acid etchingwith a 9% phosphoric acid solution for 20 s provided the most favorable visualization of the osteocyte lacunar–canalicular network. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc. 相似文献