Large-Scale Physical Forcing of Thin Layer Dynamics

2001 ◽  
Author(s):  
Margaret M. Dekshenieks ◽  
Percy L. Donaghay ◽  
Thomas R. Osborn ◽  
Ann E. Gargett
Keyword(s):  
Thin Layer ◽  
Large Scale ◽  
Physical Forcing

Large-Scale Physical Forcing of Thin Layer Dynamics

2002 ◽  
Author(s):  
Margaret A. McManus ◽  
Percy L. Donaghay ◽  
Thomas R. Osborn
Keyword(s):  
Thin Layer ◽  
Large Scale ◽  
Physical Forcing

scholarly journals Modelling and pH Control in Raceway and Thin-Layer Photobioreactors for Wastewater Treatment

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1099
Author(s):  
María José Rodríguez-Torres ◽  
Ainoa Morillas-España ◽  
José Luis Guzmán ◽  
Francisco Gabriel Acién
Keyword(s):  
Wastewater Treatment ◽  
Thin Layer ◽  
Large Scale ◽  
Control Period ◽  
Ph Control ◽  
Thin Layers ◽  
Control Algorithms ◽  
Treatment Processes ◽  
Overall Performance ◽  
Reduction Of Co2

One of the most critical variables in microalgae-related processes is the pH; it directly determines the overall performance of the production system especially when coupling with wastewater treatment. In microalgae-related wastewater treatment processes, the adequacy of pH has a large impact on the microalgae/bacteria consortium already developing on these systems. For cost-saving reasons, the pH is usually controlled by classical On/Off control algorithms during the daytime period, typically with the dynamics of the system and disturbances not being considered in the design of the control system. This paper presents the modelling and pH control in open photobioreactors, both raceway and thin-layer, using advanced controllers. In both types of photobioreactors, a classic control was implemented and compared with a Proportional–Integral (PI) control, also the operation during only the daylight period and complete daily time was evaluated. Thus, three major variables already studied include (i) the type of reactors (thin-layers and raceways), (ii) the type of control algorithm (On/Off and PI), and (iii) the control period (during the daytime and throughout the daytime and nighttime). Results show that the pH was adequately controlled in both photobioreactors, although each type requires different control algorithms, the pH control being largely improved when using PI controllers, with the controllers allowing us to reduce the total costs of the process with the reduction of CO2 injections. Moreover, the control during the complete daily cycle (including night) not only not increases the amount of CO2 to be injected, otherwise reducing it, but also improves the overall performance of the production process. Optimal pH control systems here developed are highly useful to develop robust large-scale microalgae-related wastewater treatment processes.

The ignition of a thin layer of explosive by impact

1974 ◽  
Vol 338 (1612) ◽  
pp. 77-93 ◽  
Keyword(s):  
Pressure Drop ◽  
Thin Layer ◽  
High Speed ◽  
Large Scale ◽  
Flow Speed ◽  
Thin Layers ◽  
Drop Weight ◽  
Flow Speeds ◽  
Show Evidence ◽  
Weight Impact

The behaviour of thin layers of solid materials under drop-weight impact is studied with the aid of high-speed photographic and pressure-measuring techniques. Photographic sequences taken with a high-speed framing camera show that explosive materials suffer large-scale deformation before initiation of explosion. The sample may undergo plastic flow in bulk, show evidence of partial fusion, and even (with PETN) melt completely. There is also evidence of Munroe jetting and instability of flow of material at the anvil/layer interfaces. The flow speed of the sample during these processes is considerable and may reach 300 m/s. When ignition of the layer occurs it does so at a small number of local hot spots, following which rapid combustion develops at speeds of 200-700 m/s. Strain-gauge measurements show that the pressures attained during drop-weight impact are typically 0.5-1 GPa (5–10 kbar) and the duration of impact 300–500 μs. In the course of impact of a thin layer of granular material a sharp pressure drop may occur, frequently from several hundred MPa down to zero. With an explosive layer, ignition occurs immediately following the instant of the pressure drop. The sudden fall in pressure is due to mechanical failure of the sample, and correlation of the two experiments shows that this is the cause of the very high flow speeds attained during impact. On the basis of these results a possible mechanism of ignition is suggested.

scholarly journals Efficient CdTe Nanocrystal/TiO2 Hetero-Junction Solar Cells with Open Circuit Voltage Breaking 0.8 V by Incorporating A Thin Layer of CdS Nanocrystal

Nanomaterials ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 614 ◽  
Author(s):  
Xianglin Mei ◽  
Bin Wu ◽  
Xiuzhen Guo ◽  
Xiaolin Liu ◽  
Zhitao Rong ◽  
...  
Keyword(s):  
Solar Cells ◽  
Thin Layer ◽  
Large Scale ◽  
Open Circuit Voltage ◽  
Open Circuit ◽  
Band Alignment ◽  
Ambient Conditions ◽  
Solution Processed ◽  
Processing Technologies ◽  
Cdte Nanocrystal

Nanocrystal solar cells (NCs) allow for large scale solution processing under ambient conditions, permitting a promising approach for low-cost photovoltaic products. Although an up to 10% power conversion efficiency (PCE) has been realized with the development of device fabrication technologies, the open circuit voltage (Voc) of CdTe NC solar cells has stagnated below 0.7 V, which is significantly lower than most CdTe thin film solar cells fabricated by vacuum technology (around 0.8 V~0.9 V). To further improve the NC solar cells’ performance, an enhancement in the Voc towards 0.8–1.0 V is urgently required. Given the unique processing technologies and physical properties in CdTe NC, the design of an optimized band alignment and improved junction quality are important issues to obtain efficient solar cells coupled with high Voc. In this work, an efficient method was developed to improve the performance and Voc of solution-processed CdTe nanocrystal/TiO2 hetero-junction solar cells. A thin layer of solution-processed CdS NC film (~5 nm) as introduced into CdTe NC/TiO2 to construct hetero-junction solar cells with an optimized band alignment and p-n junction quality, which resulted in a low dark current density and reduced carrier recombination. As a result, devices with improved performance (5.16% compared to 2.63% for the control device) and a Voc as high as 0.83 V were obtained; this Voc value is a record for a solution-processed CdTe NC solar cell.

scholarly journals Mathematical modelling of the thin layer drying of pineapple (Ananas comosus, L.): experiment at village-scale in a greenhouse type solar dryer

2019 ◽  
Vol 20 (2) ◽  
pp. 1-10
Author(s):  
Ignacio López Cerino ◽  
Irineo Lorenzo López Cruz ◽  
Serm Janjai ◽  
Marcus Nagle ◽  
Busarakorn Mahayothee ◽  
...  
Keyword(s):  
Experimental Data ◽  
Moisture Content ◽  
Thin Layer ◽  
Large Scale ◽  
Linear Regression Analysis ◽  
Ananas Comosus ◽  
Solar Dryer ◽  
Thin Layer Drying ◽  
Best Fitting ◽  
Drying Curves

The objectives of this research were two: first to investigate experimentally the behavior of pineappl (Ananas comosus, L.) thin layer drying in a greenhouse-type solar dryer and second to describe the best fitting kinetic and mathematical model taken from literature. A large scale greenhouse dryer designed and installed at Silpakorn University, Nakhon Pathom, Thailand was used to dry slices 1 cm width at temperature range between 25-60 °C with relative humidity between 50-90%. Nine statistical models, either empirical or semi-empirical, were tested in order to validate the experimental data. A non-linear regression analysis conducted by a statistical computer program was applied to evaluate the constants of all the models. The parameter values, root mean square error (RMSE), mean absolute error (MAE) and modelling efficiency (EFF) of the nine models were calculated. Comparison outcomes of two experiments are displayed between the predicted moisture content and the observed pineapple moisture content. Hasibuan and Daud drying model proved to describe the best pineapple solar drying curves. The two experiments were carried out on sunny days, the second experiment on the third day showed cloudiness decreasing the solar radiation. Mathematical models of pineapple drying in a greenhouse dryer have not been found so far in the literature. Drying curves obtained from experiments showed that the constant drying and the falling drying rate periods exist. Nine thin-layer drying models were fitted to two experimental data in order to describe the drying characteristics of pineapple founding that the Hasibuan and Daud model was the best fitting.

Micro-analysis for quinidine in serum by thin-layer chromatography followed by fluorescence densitometry.

1983 ◽  
Vol 29 (12) ◽  
pp. 2100-2102 ◽  
Author(s):  
M Kelner ◽  
D N Bailey
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Large Scale ◽  
Internal Standard ◽  
Peak Height ◽  
Peak Height Ratio ◽  
Height Ratio ◽  
Coefficients Of Variation ◽  
Micro Analysis ◽  
Layer Chromatography

Abstract We report a thin-layer-chromatographic micro-analysis for quinidine in serum, with detection by fluorescence densitometry. Quinidine is extracted from 20 microL of serum at pH 13 into 3 mL of hexane/acetone solution (80/20 by vol) containing N-(1-naphthyl)ethylenediamine as internal standard. The extract is concentrated and applied to silica-gel-impregnated plates for conventional thin-layer chromatography. Quinidine is identified from its RF value and quantified from the peak-height ratio between quinidine and the internal standard, relative to that of simultaneously extracted serum standards. The proposed assay is sensitive (to 0.2 mg/L), specific for unmetabolized quinidine, precise (between-run coefficients of variation less than 6%), and readily adaptable to large-scale "batch" analysis. Peak-height ratio is linearly related to concentration to at least 20 mg/L. Quinidine concentrations in the serum of patients, as measured by the proposed method (x) and by a traditional double-extraction spectrofluorometric assay (y), were related as follows: y = 0.994x + 0.276 (r = 0.989, n = 20).

Metasomatism in the Whin Sill of the North of England. Part II: Hydrothermal Alteration by Juvenile Solutions

1929 ◽  
Vol 66 (5) ◽  
pp. 221-238 ◽  
Author(s):  
L. R. Wager
Keyword(s):  
Thin Layer ◽  
Hydrothermal Alteration ◽  
Outer Surface ◽  
Large Scale ◽  
General Character ◽  
Small Scale ◽  
Hydrothermal Solutions ◽  
Vein Quartz ◽  
Columnar Jointing ◽  
The North

In Teesdale and Weardale, at all exposures that have been examined, the Whin Sill is cut by a system of approximately vertical, sweeping, joint planes. These are distinct in general character from, and are on a larger scale than, the columnar jointing which is conspicuous in all vertical scars of Whin Sill. The pattern of the larger scale jointing on a horizontal surface varies with the depth within the sill; Fig. 1 shows diagrammatically the appearance at a depth of about 10 feet below the top of the sill; the inset Fig. 2, of the upper surface of the sill, shows how the joints have a more irregular course in the more rapidly cooled part of the dolerite. The joints do not usually pass from the dolerite into the adjacent sediment and Fig. 2 also shows a thin layer of baked sediment, attached to the outer surface of the sill, which the joint does not penetrate. The large scale jointing is often displaced by the small scale columnar jointing in a way that proves the large scale jointing to be the earlier. For the purposes of this paper, the early, large scale, joints will be referred to simply as the early joints. The walls of the early joints, for a distance of an inch or so, have been altered by hydrothermal solutions, to a rock which, although varying in composition with the distance from the joint, consists essentially of chlorite, quartz, and carbonate. The joint walls are usually about a quarter of an inch apart, and the space between them is filled with calcite and quartz. The calcite is present in greater abundance than the quartz which occurs in well shaped crystals of vein-quartz habit.

An improved method for rapid, large-scale thin-layer chromatographic urine screening for drugs of abuse

1971 ◽  
Vol 60 ◽  
pp. 95-101 ◽  
Author(s):  
J.R. Broich ◽  
D.B. Hoffman ◽  
S. Andrayauskas ◽  
L. Galante ◽  
C.J. Umberger
Keyword(s):  
Thin Layer ◽  
Large Scale ◽  
Drugs Of Abuse ◽  
Improved Method ◽  
Urine Screening

SOME METACOMPUTING EXPERIENCES FOR SCIENTIFIC APPLICATIONS

1999 ◽  
Vol 09 (02) ◽  
pp. 243-252 ◽  
Author(s):  
O. LARSSON ◽  
M. FEIG ◽  
L. JOHNSSON
Keyword(s):  
Molecular Dynamics ◽  
Thin Layer ◽  
High Performance ◽  
Large Scale ◽  
Distributed Memory ◽  
Parallel Applications ◽  
Globus Toolkit ◽  
Performance Measurements ◽  
Correct Execution ◽  
Application Codes

We demonstrate good metacomputing efficiency and portability for three typical large-scale parallel applications; one molecular dynamics code and two electromagnetics codes. The codes were developed for distributed memory parallel platforms using Fortran77 or Fortran90 with MPI. The performance measurements were made for a testbed of two IBM SPs connected through the vBNS. No change of the application codes were required for correct execution of the codes on the testbed using the Globus Toolkit for the required metacomputing services. However, we observe that for good performance, it may be necessary for MPI codes to make use of overlapped computation and communication. For such MPI codes, a communications library designed for hierarchical or clustered communication can yield very good metacomputing efficiencies when high-performance networks, such as the vBNS or the Abilene networks, such as the vBNS or the Abilene networks, are used for platform connectivity. We demonstrate this by inserting a thin layer between the MPI application and the MPI libraries, providing some clustering of communications between platforms.

Determination of drugs in plasma by high-performance thin-layer chromatography.

1978 ◽  
Vol 24 (8) ◽  
pp. 1386-1392 ◽  
Author(s):  
D C Fenimore ◽  
C M Davis ◽  
C J Meyer
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
High Performance ◽  
Large Scale ◽  
Ultraviolet Spectrophotometry ◽  
Reflectance Spectrometry ◽  
Ultraviolet Reflectance ◽  
Layer Chromatography

Abstract High-performance thin-layer chromatography was used to determine chlorpromazine, amitriptyline, nortriptyline, imipramine, desipramine, phenobarbital, and phenytoin in plasma, to demonstrate the utility of this technique for routine analysis. We quantitated the separated components by use of ultraviolet reflectance spectrometry with detection limits as low as 1 microgram/liter. Regressions of psychoactive agents extracted from plasma were linear over the range of 0 to 300 microgram/liter. The anti-convulsant drugs, phenobarbital and phenytoin, were determined over a range of 0 to 50 mg/liter. Analyses were rapid, reproducible, and well-suited to large-scale programs. Separated components also can be identified in situ by ultraviolet spectrophotometry.

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