Characterization of Cathode Chromium Incorporation during Mid-Term Stack Operation under Various Operational Conditions

2019 ◽  
Vol 7 (1) ◽  
pp. 245-254 ◽  
Author(s):  
Norbert H. Menzler ◽  
L. G. de Haart ◽  
Doris Sebold
Keyword(s):  
Operational Conditions

Freight Railroads Adjacent to High-Speed Rail: Assessing the Risk

2014 ◽  
Author(s):  
John Cockle
Keyword(s):  
High Speed ◽  
Objective Assessment ◽  
Assessment Model ◽  
Exact Probability ◽  
High Speed Rail ◽  
Operational Conditions ◽  
Hazard Risk ◽  
Class 1 ◽  
Potential Applications

By law, the California High-Speed Train System (CHSTS) must be designed and built along established transportation corridors, includes adjacent to or in shared right-of-ways with Class 1 freight railroads. The Adjacent Railroad Hazard Risk Assessment Model (ARHRAM) has been developed as a tool to assist the California High-Speed Rail Authority (Authority) in the assessment of hazard risk posed by adjacent freight railroads. This assessment assists the Authority in the risk-based prioritization of resources meant to mitigate the hazards presented by the adjacency of freight railroad operations. Use of the ARHRAM allows the Authority to apply consistent, objective assessment techniques across the entire system and throughout the various developmental phases. ARHRAM uses both quantitative and qualitative techniques to develop a characterization of the hazard risk at a particular location, as opposed to an exact probability of the occurrence of a derailment. FRA-reportable derailment data is used to establish the frequency of a derailment on the adjacent railroad at any location, normalized against the performance over a 10-year period. A review of characteristics at a particular location is then conducted, examining for the presence of sixteen separate site characteristics including alignment geometry, train control methods, speed, access, grade crossings, special trackwork, and operational modes. Each characteristic is given a value according to its presence (or not) and the total multiplied by the derailment factor for the railroad and volume of trains operated at the location. The result is a characterization of the levels of site-specific hazard risk that allows the Authority to prioritize mitigations (resources) in order to reduce risk to an acceptable level. The model is dynamic in that it can be modified if new characteristics need to be introduced or existing characteristics modified, and the model can be re-run should physical or operational conditions change in the future. This paper applies the model to an existing rail corridor adjacent the CHSTS, demonstrating how appropriate mitigations can be determined and residual risk accepted. The paper also identifies future applications of the ARHRAM in the development of the CHSTS, and potential applications for other systems or modes.

scholarly journals Synthesis and characterization of modified activated carbon (MgO/AC) for methylene blue adsorption: optimization, equilibrium isotherm and kinetic studies

2021 ◽  
Author(s):  
Vahab Ghalehkhondabi ◽  
Alireza Fazlali ◽  
Keyhan Ketabi
Keyword(s):  
Methylene Blue ◽  
Activated Carbon ◽  
Natural Waters ◽  
Sol Gel ◽  
Kinetic Studies ◽  
Maximum Adsorption Capacity ◽  
Human Beings ◽  
Operational Conditions ◽  
Coating Method

Abstract Methylene blue (MB) is the cationic dye that is widely used for coloring cotton, wool, and silk. Since MB is harmful to human beings and toxic to microorganisms, there is the need to find cheap and efficient methods for removal of MB from wastewater prior to disposal into natural waters. In the present study, MB adsorption potential of MgO/AC prepared using a sol–gel-thermal deep-coating method was compared with the activated carbon (AC). The central composite design (CCD) as a method of the response surface methodology (RSM) was applied to minimize the number of runs and process optimization. The characterization of the microporous MgO/AC composite showed that the magnesium oxide nanoparticles were successfully coated on the AC and the BET specific surface area of AC and MgO/AC were 1,540 and 1,246 m2/g, respectively. The MB removal efficiency and the maximum adsorption capacity of AC and MgO/AC were 89.6, 97.5% and 571.7, 642.3 mg/g, respectively under optimum operational conditions of initial dye concentration of 100.9 mg/L, the adsorbent dosage of 69.4 mg/100 mL, pH of 10.2 and contact time of 149.1 min. According to an analysis of variance (ANOVA), the initial dye concentration and its interaction with the other effective factors have a large impact on adsorption efficiency. Furthermore, the mechanism of adsorption followed the Langmuir isotherm (R2 = 0.9935, Δqe = 2.9%) and adsorption kinetics fitted by the pseudo-second-order model (R2 = 0.9967, Δqe = 6.6%). Finally, our results suggest that the prepared MgO/AC is an efficient and promising material for dye wastewater treatment.

scholarly journals Hydrothermal–Microwave Processing for Starch Extraction from Mexican Avocado Seeds: Operational Conditions and Characterization

Processes ◽  
2020 ◽  
Vol 8 (7) ◽  
pp. 759 ◽  
Author(s):  
Rafael G. Araújo ◽  
Rosa M. Rodríguez-Jasso ◽  
Héctor A. Ruiz ◽  
Mayela Govea-Salas ◽  
Walfred Rosas-Flores ◽  
...  
Keyword(s):  
Extraction Yield ◽  
Absorption Capacity ◽  
Molecular Spectra ◽  
Operational Conditions ◽  
Assisted Extraction ◽  
Conventional Extraction ◽  
Avocado Starch ◽  
Isothermal Mode ◽  
Agroindustrial Residue

Avocado seeds are an agroindustrial residue widely produced in Mexico that are causing various environmental problems due to their accumulation. The evaluation of avocado residues to recover biopolymers by microwave-assisted extraction (MAE) and the characterization of avocado starch properties were studied in the present work. A central-composite design was used to optimize the MAE process. Moreover, a comparison was performed between MAE non-isothermal mode (NO–ISO) and conventional extraction. Starch optimization by MAE was obtained at 161.09 °C for 56.23 min with an extraction yield of 49.52% ± 0.69%, while with NO–ISO at 161 °C was obtained 45.75% ± 2.18%. Conventional extraction was 39.04% ± 2.22%. Compared with conventional starch, MAE starch showed similar proprieties and molecular spectra. In contrast, MAE starch showed high solubility, low water absorption capacity, a non-granular structure with small particle size (<2 µm) and polydispersity of fragments at different sizes of polymers. Therefore, MAE is a viable technology to extract the starch, and avocado seed can be considered an excellent starch source for the development of novel functional foods, contributing to promoting sustainability across the food chain.

scholarly journals Performance Characterization of the Smartphone Video Guidance Sensor as Vision-Based Positioning System

Sensors ◽  
2020 ◽  
Vol 20 (18) ◽  
pp. 5299
Author(s):  
Nasir Hariri ◽  
Hector Gutierrez ◽  
John Rakoczy ◽  
Richard Howard ◽  
Ivan Bertaska
Keyword(s):  
Sampling Rate ◽  
Target Velocity ◽  
Error Statistics ◽  
Operational Conditions ◽  
Error Metrics ◽  
Orientation Vector ◽  
State Position ◽  
Overall Performance ◽  
Video Guidance

The Smartphone Video Guidance Sensor (SVGS) is a vision-based sensor that computes the six-state position and orientation vector of a target relative to a coordinate system attached to a smartphone. This paper presents accuracy-characterization measurements of the Smartphone Video Guidance Sensor (SVGS) to assess its performance as a position and attitude estimator, evaluating its accuracy in linear and angular motion for different velocities and various types of targets based on the mean and standard deviation errors between SVGS estimates and known motion profiles, in both linear and angular motions. The study also examines the effects of target velocity and sampling rate on the overall performance of SVGS and provides an overall assessment of SVGS’ performance as a position/attitude estimator. While the error metrics are dependent on range and camera resolution, the results of this paper can be scaled to other operational conditions by scaling the blob size in pixels (the light markers identified in the images) relative to the total resolution (number of pixels) of the image. The error statistics of SVGS enable its incorporation (by synthesis of a Kalman estimator) in advanced motion-control systems for navigation and guidance.

Characterization of electrodes and performance tests on MEAs with varying platinum content and under various operational conditions

2013 ◽  
Vol 38 (22) ◽  
pp. 9431-9437 ◽  
Author(s):  
Dedi Rohendi ◽  
Edy Herianto Majlan ◽  
Abu Bakar Mohamad ◽  
Wan Ramli Wan Daud ◽  
Abdul Amir Hassan Kadhum ◽  
...  
Keyword(s):  
Performance Tests ◽  
Operational Conditions ◽  
Platinum Content ◽  
And Performance

scholarly journals Characterization of Combinatorially Independent Permutation Separability Criteria

2005 ◽  
Vol 12 (04) ◽  
pp. 331-345 ◽  
Author(s):  
Paweł Wocjan ◽  
Michał Horodecki
Keyword(s):  
Density Matrix ◽  
The State ◽  
Necessary Condition ◽  
Trace Norm ◽  
Mixed States ◽  
Graphical Notation ◽  
Operational Conditions ◽  
Separability Criteria ◽  
Partial Transpose

The so-called permutation separability criteria are simple operational conditions that are necessary for separability of mixed states of multipartite systems: (1) permute the indices of the density matrix and (2) check if the trace norm of at least one of the resulting operators is greater than one. If it is greater than one then the state is necessarily entangled. A shortcoming of the permutation separability criteria is that many permutations give rise to equivalent separability criteria. Therefore, we introduce a necessary condition for two permutations to yield independent criteria called combinatorial independence. This condition basically means that the map corresponding to one permutation cannot be obtained by concatenating the map corresponding to the second permutation with a norm-preserving map. We characterize completely combinatorially independent criteria, and determine simple permutations that represent all independent criteria. The representatives can be visualized by means of a simple graphical notation. They are composed of three basic operations: partial transpose, and two types of so-called reshufflings. In particular, for a four-partite system all criteria except one are composed of partial transpose and only one type of reshuffling; the exceptional one requires the second type of reshuffling. Furthermore, we show how to obtain efficiently a simple representative for every permutation. This method allows to check easily if two permutations are combinatorially equivalent or not.

scholarly journals Partial Purification and Characterization of a Heat Stable α-Amylase from a Thermophilic Actinobacteria, Streptomyces sp. MSC702

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Renu Singh ◽  
Vijay Kumar ◽  
Vishal Kapoor
Keyword(s):  
Enzyme Activity ◽  
Biochemical Characterization ◽  
Enzyme Stability ◽  
Potato Starch ◽  
Tween 80 ◽  
Partial Purification ◽  
Amylolytic Enzyme ◽  
Operational Conditions ◽  
Heat Stable

A partial purification and biochemical characterization of the α-amylase from Streptomyces sp. MSC702 were carried out in this study. The optimum operational conditions for enzyme substrate reaction for amylolytic enzyme activity from the strain were evaluated. The optimum pH, temperature, and incubation period for assaying the enzyme were observed to be 5.0, 55°C, and 30 min, respectively. The extracellular extract was concentrated using ammonium sulfate precipitation. It was stable in the presence of metal ions (5 mM) such as K+, Co2+, and Mo2+, whereas Pb2+, Mn2+, Mg2+, Cu2+, Zn2+, Ba2+, Ca2+, Hg2+, Sn2+, Cr3+, Al3+, Ag+, and Fe2+ were found to have inhibitory effects. The enzyme activity was also unstable in the presence of 1% Triton X-100, 1% Tween 80, 5 mM sodium lauryl sulphate, 1% glycerol, 5 mM EDTA, and 5 mM denaturant urea. At temperature 60°C and pH 5.0, the enzyme stability was maximum. α-amylase retained 100% and 34.18% stability for 1 h and 4 h, respectively, at 60°C (pH 7.0). The enzyme exhibited a half-life of 195 min at 60°C temperature. The analysis of kinetic showed that the enzyme has Km of 2.4 mg/mL and Vmax of 21853.0 μmol/min/mg for soluble potato starch. The results indicate that the enzyme reflects their potentiality towards industrial utilization.

scholarly journals CARACTERIZAÇÃO TÉCNICA DO ASPERSOR PLONA-RL300

Irriga ◽  
2005 ◽  
Vol 10 (1) ◽  
pp. 53-63 ◽  
Author(s):  
Giuliani Do Prado ◽  
Alberto Colombo
Keyword(s):  
Flow Rate ◽  
Clustering Analysis ◽  
Water Distribution ◽  
Distribution Curve ◽  
Operating Pressure ◽  
Geometric Shapes ◽  
Operational Conditions ◽  
Uniformity Test ◽  
Caixa Postal

CARACTERIZAÇÃO TÉCNICA DO ASPERSOR PLONA-RL300  Giuliani do Prado; Alberto ColomboDepartamento do Engenharia, Universidade Federal de Lavras, Caixa Postal 37, CEP 37200-000, Lavras – MG,  [email protected]  1 RESUMO O trabalho teve como objetivo apresentar as características operacionais do aspersor, do tipo canhão hidráulico com mecanismo setorial de reversão lenta, da marca PLONA, modelo RL300, que foram determinadas no Setor de Hidráulica da Universidade Federal de Lavras, em Lavras - MG. Foram realizadas quarenta e cinco determinações de vazão, raio de alcance e perfil radial de distribuição de água, abrangendo nove diferentes diâmetros do bocal principal (22, 24, 26, 28, 30, 32, 34, 36 e 38 mm) e cinco valores de pressões de serviço, variando deste 294 até 686 kPa, em intervalos de 98 kPa. Os valores de vazão (Q em m3 h-1) e raio de alcance (R em m) observados nos ensaios foram relacionados ao diâmetro do bocal principal (b em mm) e à pressão de serviço (P em kPa) através das equações: Q = 0,00145 b2,189 P0,504 (r2 = 0,9963) e R = 0,553 b0,533 P0,436 (r2 = 0,9611). Os perfis radiais de aplicação de água foram adimensionalizados e submetidos à análise de agrupamento (método “K-Means”) que indicou a ocorrência de perfis radiais com três formatos geométricos distintos e também caracterizou as condições operacionais do aspersor (bocal versus pressão), que determinam a ocorrência de cada umas das três formas geométricas distintas do perfil radial de aplicação de água. UNITERMOS: aspersores, perfil radial de aplicação, teste de uniformidade.  PRADO, G.; COLOMBO, A.TECHINAL CHARACTERIZATION OF THE SPRINKLER PLONA-RL300  2 ABSTRACT This work aimed to present performance characteristics of the PLONA-RL300 slow reversion gun-type sprinkler that were evaluated at the Hydraulics Section of the Universidade Federal de Lavras, in Lavras - MG, Brazil. Sprinkler flow rate, reach radius and water distribution curve were evaluated at forty-five different combinations of sprinkler nozzle diameter (22, 24, 26,28, 30, 32, 34, 36, and 38 mm) and operating pressure (from 294 kPa up to 686 kPa at regular 98 kPa intervals). Values of sprinkler flow rate (Q in m3 h-1) and sprinkler reach radius (R in m), observed at different combinations of nozzle size (b in mm) and operating pressure (P in kPa), were used to fit the following equations: Q = 0.00145 b2.189 P0.504 (r2 = 0.9963) and R = 0.553 b0.533 P0.436 (r2 = 0.9611). Water distribution curves were normalized and submitted to clustering analysis (K-Means algorithm). Based on the clustering analysis results, we were able to identify the occurrence of normalized distribution curves with three different geometric shapes and also to identify sprinkler operational conditions associated to each one of the three normalized distribution curve geometric shapes. KEYWORDS: rotating sprinkler, water distribution curve, uniformity test

scholarly journals Wind speed measurements using distributed fiber optics: a windtunnel study

2019 ◽  
Author(s):  
Justus G. V. van Ramshorst ◽  
Miriam Coenders-Gerrits ◽  
Bart Schilperoort ◽  
Bas J. H. van de Wiel ◽  
Jonathan G. Izett ◽  
...  
Keyword(s):  
Wind Speed ◽  
Wind Tunnel ◽  
Fiber Optics ◽  
Sonic Anemometer ◽  
Surface Wind ◽  
Turbulent Heat ◽  
Distributed Temperature Sensing ◽  
Near Surface ◽  
Operational Conditions

Abstract. Near-surface wind speed is typically only measured by point observations. The Actively Heated Fiber-Optic (AHFO) technique, however, has the potential to provide high-resolution distributed observations of wind speeds, allowing for better characterization of fine-scale processes. Before AHFO can be widely used, its performance needs to be tested in a range of settings. In this work, experimental results on this novel observational wind-probing technique are presented. We utilized a controlled wind-tunnel setup to assess both the accuracy and the precision of AHFO under a range of operational conditions. The technique allows for wind speed characterization with a spatial resolution of 0.3 m on a 1 s time scale. The flow in the wind tunnel was varied in a controlled manner, such that the mean wind, ranged between 1 and 17 m/s. The AHFO measurements are compared to sonic anemometer measurements and show a high overall correlation (0.85–0.98). Both the precision and accuracy of the AHFO measurements were also greater than 95 %. We conclude that the AHFO has potential to be employed as an outdoor observational technique. It allows for characterization of spatially varying fields of mean wind in complex terrain, such as in canopy flows or in sloping terrain. In the future, the technique could be combined with conventional Distributed Temperature Sensing (DTS) for turbulent heat flux estimation in micrometeorological/hydrological applications.

Sign in / Sign up

Export Citation Format

Share Document