photoluminescence and carrier transport in nanocrystalline tio2

... micelle” (path I in Fig 6) These SDS-coated TiO2 particles then aggregate into stacked TiO2 nanorods; further calcination at higher temperatures results in the nanocrystalline TiO2 rods and hollow ... that microstructure and phase content of the nanocrystalline TiO2 can be tailor-made by properly manipulating those parameters during the combined sol–gel and hydrothermal processing Experimental ... nanorods of ∼10 nm in diameter The nanocrystalline TiO2 thus prepared appears to have an engraved surface morphology and consists mainly of the anatase and minor amount of rutile and brookite It...

Ngày tải lên: 20/03/2014, 13:07

... mathematical modeling, and numerical methods His present interests are in understanding and predicting the transport and fate of sediments and contaminants in surface and ground waters and the effects ... and commercial fishers as well as for swimming, windsurfing, surfing, scuba diving, snorkeling, and shellfishing Since 1995, fish consumption advisories and health warnings have been posted in ... transported downstream, and again © 2009 by Taylor & Francis Group, LLC Sediment and Contaminant Transport in Surface Waters deposited in low-flowing and quiescent areas of the river (including...

Ngày tải lên: 18/06/2014, 22:20

... multiplying or dividing by two For example, very coarse sand is defined as particles with diameters between and mm, and very fine sand is defined as particles with diameters between 1/8 and 1/16 ... and the units of d and ws are cm and cm/s, respectively For d in µm and ws in µm/s, ws = 0.898 d2, or ws © 2009 by Taylor & Francis Group, LLC d2 (2.6) 32 Sediment and Contaminant Transport in ... Sediment and Contaminant Transport in Surface Waters mineralogy and size of an inorganic particle tend to be related Large particles with a diameter greater than 62.5 µm are defined as sands and gravels...

Ngày tải lên: 18/06/2014, 22:20

... obtained by inserting the coring tube into the bottom sediments; this core and its contents then are retrieved and inserted into the Shaker frame The thickness of the sediment in the coring tube ... of sand had eroded at this site between fall and spring In a brief bathymetric survey of the area, it was determined that water depths in this area had increased by up to 1.5 m, again indicating ... the lowering of the three dams in 1987 and the subsequent modification and increase in the flow velocities In this river, as shown above in Figures 3.9(c), (d), and (e), as well as in the Housatonic...

Ngày tải lên: 18/06/2014, 22:20

... the outer cylinder rotating and the inner cylinder stationary In this way, a reasonably uniform velocity gradient can be generated in the fluid in the annular gap between the cylinders The width ... analyzer As shown by Camp and Stein (1943) and Saffman and Turner (1956), the flocculation rate in a laminar flow can be related to the rate in a turbulent flow by replacing the laminar shear by an effective ... long and 10 cm wide The tube was insulated with styrofoam on all sides, top, and bottom and kept away from windows and drafts Experiments were usually performed in the late afternoon and evening...

Ngày tải lên: 18/06/2014, 22:20

... Basin and quite weak in the deeper parts of the basins 5.5.2.2 A North Wind For a north wind, both wave height and wave period increase southward with increasing wind fetch For the Western Basin, ... calculated and measured currents near surface and near bottom at the Boeing station are shown in Figure 5.14 Despite difficulties and uncertainties in averaging measurements and calculations in the ... and Contaminant Transport in Surface Waters 5.1.5 SIGMA COORDINATES In a Cartesian grid, the vertical distances between grid points depend only on z and not on x or y In a variable-depth basin,...

Ngày tải lên: 18/06/2014, 22:20

... and sediment inflow The transports in the Lower Fox and Saginaw rivers are discussed here to illustrate various interesting features of sediment transport in rivers and the modeling of this transport ... to changes in particle size distributions and the inclusion of bedload and bed armoring All are significant and need to be included in sediment transport modeling 6.3.3 TRANSPORT IN A CURVED ... Sediment and Contaminant Transport in Surface Waters west wind (the dominant wind throughout the year), a northeast wind (the dominant direction during large storms), a southeast wind, and a northwest...

Ngày tải lên: 18/06/2014, 22:20

... Sediment and Contaminant Transport in Surface Waters the steady-state partitioning of an HOC between sedimentary particles and water are discussed subsequently In this first set of experiments, linear ... constant and independent of dissolved HOC concentration at constant temperature) were obtained However, nonlinear and interactive effects on isotherms are often observed and have been reported in the ... Francis Group, LLC 300 Sediment and Contaminant Transport in Surface Waters size and density distributions are not wide, and the variation in k is less than Because of this and because of our meager...

Ngày tải lên: 18/06/2014, 22:20

... EROSION/DEPOSITION AND TRANSPORT Two HOC transport problems are discussed in this section: (1) the transport of PCBs in the Saginaw River, including the assumption of equilibrium partitioning; and (2) the transport ... that remains in the water decreases as the wind speed increases, the total amount of PCBs remaining in the water increases because of the very nonlinear increase of sediment and contaminant resuspension ... Group, LLC 316 Sediment and Contaminant Transport in Surface Waters A simple and idealized problem of contaminant release and transport during environmental dredging is discussed in Section 8.6; the...

Ngày tải lên: 18/06/2014, 22:20

... }, as obtained with MLE and O&M The observation length is N = 32 in Figure and N = 64 in Figure Marks indicate simulation results while the thin solid lines are drawn to ease the reading of the ... obtained, timing and phase estimates are computed in closed form as indicated in (21) and (22), respectively In summary, the difficult and time-consuming part in the estimation of (ν, ε, ϕ) is the one ... of two FFTs instead of a single FFT In addition to carrier synchronization, however, the MLE also provides timing recovery Actually, from (16) and (21) we see that computing the timing estimate...

Ngày tải lên: 22/06/2014, 19:20

... to investigate disorder and its resulting transport properties in previously unexplored contexts In the last decade, the discovery of graphene and the renewed interest in topological effects in ... delocalized in the absence of disorder, as shown by Anderson Therefore, disorder plays an important role in determining the transport properties, and on the other hand, disorder can be deliberately introduced ... of interest to studies concerning anomalous transport Finally, we summarize the main results of this thesis and offer an outlook in Chapter Chapter Physics Background and Mathematical Preliminaries...

Ngày tải lên: 09/09/2015, 08:16

... momentum and spin relaxation times Both quantity increase with increasing electron carrier density (e) Linear dependence of momentum and spin relaxation times showing that EY like spin scattering ... Charge carrier density dependent spin transport measurements in CVD single and bi-layer graphene: The carrier density dependence of spin signal, spin diffusion constant and spin polaraziation in ... on spin transport in graphene In the first part of the thesis, I demonstrate spin injection, transport and detection in CVD grown graphene-based spin valve devices by utilizing the four terminal...

Ngày tải lên: 09/09/2015, 11:18

... assigns index value of 0.0 to the interior domain and 1.0 to the exterior domain in order to separate two domains in the index field Thus, index values of 0.0 and 1.0 are substituted into the ...   in  ex  in H d x  (27) where the subscripts, in and ex, indicate the interior and exterior domains, respectively Figure II-1 Simulation domain near RBC membrane The bold line represents ... RBC and the h is size of lattice The implementation of the Flood-fill method consists of three steps: initializing the index field, drawing the boundary, and filling the interior In the initialization...

Ngày tải lên: 09/09/2015, 11:24

... which was explained by fewer defects due to folding in the lamellar, leading to a longer conjugation length and less perturbed interchain packing in longer chains This reduces the transport dependence ... boiling point solvents It was explained that the high boiling point solvent allows more time for crystallization to occur during the spin-coating process by evaporating slowly hence improving ... crystallinity in the film achieved by processing from a high boiling point solvent and substrate surface modification with SAMs It was interpreted that an ordered and tighter packing of rr-P3HT chains...

Ngày tải lên: 10/09/2015, 08:34

... endocytosis; and they are capable of producing intracellular actin and myosin filaments that are oriented in the flow direction Eskin et al (1984) investigated the shear stress effects on bovine aortic ... Control Volume in the computational domain 151 Fig 2.6 Geometry and boundary conditions for lid driven flow in an inclined square cavity 152 Fig 2.7 Grid system utilized in the inclined square cavity ... (UDF) 27 2.2.2 User Defined Scalar (UDS) 28 2.2.3 Numerical method and code verification 29 2.3 Grid generation in complex domain and Finite Volume Method in curvilinear coordinate 31 2.3.1 Grid...

Ngày tải lên: 12/09/2015, 21:13

... theoretical and practical challenges in relation to micro power generation systems Therefore, the understanding of combustion and energy transport in the micro-scale is key to optimizing the design and ... blow-off due to preheating of the incoming gases, but has a minimal effect on extinction Studies on this topic are still going on 2.3.2 Cylindrical Tubes with Backward-Facing Steps Cylindrical tubes ... ‘probe’ into the small space which is normally inaccessible to measuring devices, yielding detailed information of the parameters of interest As shown in Table 2.2, both cylindrical and planar...

Ngày tải lên: 14/09/2015, 14:05

... Hydrodynamic Stress in Stirred Bioreactors 1.2.3 Mass Transport in Stirred Bioreactors 1.2.4 Swirling Flow and Vortex Breakdown in Micro-Bioreactors 12 1.2.5 Flow and Mass Transport in Bioreactors ... rotating 159 Figure 3.10 Streamline contours in the meridional plane in the cylindrical chamber with a bottom-wall rotating; H/R = 2.0 and Re as indicated 160 Figure 3.11 Schematic of a flow in ... 14 Chapter Introduction Another variant is the effect of introducing a rotating central rod, which has been reported by Mullin et al (2000) and Husain et al (2003) Mullin et al (2000) investigated...

Ngày tải lên: 14/09/2015, 18:55

... one In both cases, the Ca2+ concentration increased gradually from the beginning of leaching, decreased after a peak, and then increased and decreased again This behavior indicates that the initial ... the transport of salts such as cations (Na+, Ca2+, Mg2+ and K+) and Cl- in a column were investigated by using a tensiometer and a four-electrode sensor, and the amounts of these salts in soil and ... of amount of moisture infiltration in column infiltration experiment Changes in precipitation, evapotranspiration, and falling infiltration are shown in Fig 15 In April and May, evapotranspiration...

Ngày tải lên: 05/09/2013, 09:38

... area, and stoichiometric flow ratio The inlet velocities of air and fuel are calculated according to [22]: u in ,c = ζ c I RTin ,c AMEA xO2 ,in Pc Ach 4F (39) u in ,a = ζ a I RTin ,a AMEA x H ,in ... cm2 serpentine flow-fields with single channel, double channel, cyclic-single channel, and symmetric-single channel patterns to investigate the effect of flow-field design High and low inlet humidity ... been obtained on a Pentium IV PC (3 GHz, GB RAM), using Windows XP operating system The geometric and the base case operating conditions are listed in Table Values of the electrochemical transport...

Ngày tải lên: 05/09/2013, 14:58

... community and its people Establishing and understanding gender differences in transport needs, access and planning is important, particularly in that men and women have different economic and socio-cultural ... travelling to and from the river, minutes of travelling for primary production purposes, and 52 minutes of travelling to and from the field In addition to this, 74 minutes are spent travelling to and ... dung, 45 minutes tending to the fire and 114 minutes (1 hour 45 minutes) preparing and cooking food Other household activities take an average of 211 minutes (3 hours 31 minutes), bringing the...

Ngày tải lên: 15/02/2014, 01:20