The Physics of Plasmas provides a comprehensive introduction to the subject, illustrating the basic theory with examples drawn from fusion, space and astrophysical plasmas. A particular strength of the book is its discussion of the various models used to describe plasma physics and the relationships between them. These include particle orbit theory, fluid equations, ideal and resistive magnetohydrodynamics, wave equations and kinetic theory. The reader will gain a firm grounding in the fundamentals, and develop this into an understanding of some of the more specialised topics. Throughout the text, there is an emphasis on the physical interpretation of plasma phenomena. Exercises are provided throughout. Advanced undergraduate and graduate students of physics, applied mathematics, astronomy and engineering will find a clear but rigorous explanation of the fundamental properties of plasmas with minimal mathematical formality. This book will also appeal to research physicists, nuclear and electrical engineers.
Abstract. In a joint NRL/Manila Observatory mission, as part of the Seven SouthEast Asian Studies program (7-SEAS), a 2-week, late September 2011 research cruise in the northern Palawan archipelago was undertaken to observe the nature of southwest monsoonal aerosol particles in the South China Sea/East Sea (SCS/ES) and Sulu Sea region. Previous analyses suggested this region as a receptor for biomass burning from Borneo and Sumatra for boundary layer air entering the monsoonal trough. Anthropogenic pollution and biofuel emissions are also ubiquitous, as is heavy shipping traffic. Here, we provide an overview of the regional environment during the cruise, a time series of key aerosol and meteorological parameters, and their interrelationships. Overall, this cruise provides a narrative of the processes that control regional aerosol loadings and their possible feedbacks with clouds and precipitation. While 2011 was a moderate El Niño-Southern Oscillation (ENSO) La Niña year, higher burning activity and lower precipitation was more typical of neutral conditions. The large-scale aerosol environment was modulated by the Madden-Julian Oscillation (MJO) and its associated tropical cyclone (TC) activity in a manner consistent with the conceptual analysis performedPublished by Copernicus Publications on behalf of the European Geosciences Union. J. S. Reid et al.: Temporal variability in South Chinas Sea aerosol propertiesby Reid et al. (2012). Advancement of the MJO from phase 3 to 6 with accompanying cyclogenesis during the cruise period strengthened flow patterns in the SCS/ES that modulated aerosol life cycle. TC inflow arms of significant convection sometimes span from Sumatra to Luzon, resulting in very low particle concentrations (minimum condensation nuclei CN < 150 cm −3 , non-sea-salt PM 2.5 < 1 µg m −3 ). However, elevated carbon monoxide levels were occasionally observed suggesting passage of polluted air masses whose aerosol particles had been rained out. Conversely, two drier periods occurred with higher aerosol particle concentrations originating from Borneo and Southern Sumatra (CN > 3000 cm −3 and non-sea-salt PM 2.5 10-25 µg m −3 ). These cases corresponded with two different mechanisms of convection suppression: lower free-tropospheric dry-air intrusion from the Indian Ocean, and large-scale TC-induced subsidence. Veering vertical wind shear also resulted in aerosol transport into this region being mainly in the marine boundary layer (MBL), although lower free troposphere transport was possible on the western sides of Sumatra and Borneo. At the hourly time scale, particle concentrations were observed to be modulated by integer factors through convection and associated cold pools. Geostationary satellite observations suggest that convection often takes the form of squall lines, which are bowed up to 500 km across the monsoonal flow and 50 km wide. These squall lines, initiated by cold pools from large thunderstorms and likely sustained by a veering vertical wind shear and aforementioned mid-troposphere dr...
Several racemic or enantiomerically pure complexes of the general type Mo(CHR)(NR‘)(O2R‘‘) that contain binaphtholate or biphenolate (O2R‘‘) ligands have been prepared and employed to ring open several achiral, racemic, or enantiomerically pure norbornenes and norbornadienes. A bimodal molecular weight distribution sometimes results from polymerization of an enantiomerically pure monomer with a racemic initiator as a consequence of a different rate of chain growth from enantiomeric metal centers. The analogous polymerization of an enantiomerically pure monomer with an enantiomerically pure initiator yields only a single polymer chain, as expected. Evaluation of the cis content of the resulting polymers suggests that cis polymer results from polymerization via syn alkylidene propagating species and that accessibility of the anti rotamer on the polymerization time scale is determined by a subtle combination of steric bulk in the biphenoxide and imido ligands. All cis polymers were found to be highly isotactic. The X-ray structures of two catalytically active species are also described. One is a THF adduct of 3,3‘-diphenyl-2,2‘-diolate-1,1‘-dinaphthyl (anti rotamer) while the other is a base-free syn species that contains the 6,6‘-dimethyl-3,3‘,5,5‘-tetra-tert-butyl-1,1‘-biphenyl-2,2‘-diolate ligand.
Dissolved organic matter (DOM) absorbance and fluorescence were used as optical proxies to track terrestrial DOM fluxes through estuaries and coastal waters by comparing models developed for several coastal ecosystems. Key to using these optical properties is validating and calibrating them with chemical measurements, such as lignin-derived phenols-a proxy to quantify terrestrial DOM. Utilizing parallel factor analysis (PARAFAC), and comparing models statistically using the OpenFluor database (http://www.openfluor.org) we have found common, ubiquitous fluorescing components which correlate most strongly with lignin phenol concentrations in several estuarine and coastal environments. Optical proxies for lignin were computed for the following regions: Mackenzie River Estuary, Atchafalaya River Estuary (ARE), Charleston Harbor, Chesapeake Bay, and Neuse River Estuary (NRE) (all in North America). The slope of linear regression models relating CDOM absorption at 350 nm (a 350) to DOC and to lignin, varied 5-10-fold among systems. Where seasonal observations were available from a region, there were distinct seasonal differences in equation parameters for these optical proxies. The variability appeared to be due primarily to river flow into these estuaries and secondarily to biogeochemical cycling of DOM within them. Despite the variability, overall models using single linear regression were developed that related dissolved organic carbon (DOC) concentration to CDOM (DOC 2 = 40 ± 2 × a + ± 350 138 16; R = 0.77; N = 130) and lignin (8) to CDOM (= 2.03 ± 0.07 × a .47 2 − 0 ± = 8 350 0.59; R 0.87; N = 130). This wide variability suggested that local or regional optical models should be developed for predicting terrestrial DOM flux into coastal oceans and taken into account when upscaling to remote sensing observations and calibrations.
Efficient routes to sulfonation and epoxidation of the double bonds in a polynorbornene backbone have been found that do not interfere with side chain functional groups of interest for making light-emitting devices. Substituted norbornene monomers were prepared with ether or thioether linkages, which were stable to sulfonation. Oligomers (25mers or 50mers) of homo- and copolymers containing diphenylanthracene (for blue-light emission), oxadiazole (for electron transport), and p-triphenylene (for hole transport) side chains were prepared via ring-opening metathesis polymerization (ROMP) of the corresponding norbornene monomers. Sulfonation of the polynorbornene backbone yielded a polyanionic material that was suitable for creating films via sequential adsorption with the polycation, poly(allylamine HCl) (PAH). Devices with an indium tin oxide (ITO) anode and an aluminum cathode were constructed. A two-layer device comprised of a layer of diphenylanthracene/oxadiazole copolymer and a layer of p-triphenylene homopolymer showed better performance in terms of efficiency and light output than a single layer of diphenylanthracene/oxadiazole. However, a single layer of polymer containing 9-mesityl-10-phenylanthracene gave the best performance, up to 21 nW and 0.3 nW/mA efficiency.
A blue-light-emitting electroluminescent polymer was prepared by ring-opening metathesis polymerization (ROMP) of a norbornene monomer that contains a diphenylanthracene chromophore as a side chain (λmax,em ) 450 nm). Norbornene monomers also were synthesized that contain an oxadiazole (for electron transport) or a tertiary arylamine (for hole transport). Oligomers (25mers or 50mers) of homo-and copolymers (Mw/Mn ) 1.02-1.08) were prepared in toluene in 95-98% yield, employing Mo(N-2,6-C6H3-i-Pr2)(CHMe2Ph)(O-t-Bu)2 as the initiator. Electroluminescent devices made with a single layer of substituted polynorbornene, an ITO anode, and an Al cathode were prepared first. Two-layer devices were then constructed in which the substituted polynorbornene was spin cast onto a 25-bilayer poly(phenylenevinylene) (PPV) heterostructure. The two-layer device performed best in terms of efficiency, light output, and threshold voltage.
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