Optimization of properties and operating parameters of a passive DMFC mini-stack at ambient temperature

2008 ◽  
Vol 180 (2) ◽  
pp. 797-802 ◽  
Author(s):  
V. Baglio ◽  
A. Stassi ◽  
F.V. Matera ◽  
A. Di Blasi ◽  
V. Antonucci ◽  
...  
Keyword(s):  
Ambient Temperature ◽  
Operating Parameters

scholarly journals Testing and evaluation of cold-start emissions from a gasoline engine in RDE test at two different ambient temperatures

2021 ◽  
Vol 11 (1) ◽  
pp. 425-434
Author(s):  
Jacek Pielecha ◽  
Kinga Skobiej ◽  
Karolina Kurtyka
Keyword(s):  
Ambient Temperature ◽  
Gasoline Engine ◽  
Cold Start ◽  
Exhaust Emissions ◽  
Operating Parameters ◽  
Time Interval ◽  
Vehicle Speed ◽  
Passenger Cars ◽  
Ambient Temperatures ◽  
The Impact

Abstract In order to better reflect the actual ecological performance of vehicles in traffic conditions, both the emission standards and the applied emission tests are being developed, for example by considering exhaust emissions for a cold engine start. This article presents the research results on the impact of ambient temperature during the cold start of a gasoline engine in road emission tests. The Real Driving Emissions (RDE) tests apply to passenger cars that meet the Euro 6 emissions norm and they are complementary to their type approval tests. A portable emissions measurement system was used to record the engine and vehicle operating parameters, as well as to measure the exhaust emissions during tests. This allowed for parameters such as engine load, engine speed and vehicle speed to be monitored. The cold start conditions for two different temperatures (8°C and 25°C) were compared in detail. Moreover, the engine operating parameters, exhaust concentration values and road emissions for the 300 s time interval, were compared. The summary of the article presents the share of a passenger car’s cold start phase for each exhaust compound in the urban part of the test and in the entire Real Driving Emissions test depending on the ambient temperature.

Effect of Operating Conditions on the Performance of Two-Bed Closed-Cycle Solid-Sorption Heat Pump Systems

1995 ◽  
Vol 117 (3) ◽  
pp. 181-186 ◽  
Author(s):  
W. Zheng ◽  
W. M. Worek ◽  
G. Nowakowski
Keyword(s):  
Ambient Temperature ◽  
System Performance ◽  
Cooling Capacity ◽  
Heat Pumps ◽  
Operating Conditions ◽  
Operating Parameters ◽  
Closed Cycle ◽  
Sorption Heat ◽  
Cycling Speed ◽  
Sorption Heat Pump

The effect of two operating parameters, the regeneration temperature and the ambient temperature, on the performance of two-bed, closed-cycle solid-sorption heat pumps is investigated. The results show that increasing the regeneration temperature can improve both the COP and cooling capacity, and the effect on cooling capacity is more significant than the COP. Increasing the regeneration temperature from 180°C to 260°C, the cooling capacity increases by 50 percent and the COP improves 20 percent. When the ambient temperature drops, the system performance increases significantly. When the ambient temperature decreases by 10°C from the design point of 35°C, the COP and cooling capacity increases by 50 percent and 40 percent, respectively. Also, the bed cycling speed should be increased to achieve the optimum system performance when the regeneration temperature is higher or the ambient temperature becomes lower.

scholarly journals Analysis and Modeling of the Wear-Out Process of a Lithium-Nickel-Manganese-Cobalt Cell during Cycling Operation under Constant Load Conditions

Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3899 ◽  
Author(s):  
Damian Burzyński ◽  
Robert Pietracho ◽  
Leszek Kasprzyk ◽  
Andrzej Tomczewski
Keyword(s):  
Ambient Temperature ◽  
Experimental Research ◽  
Discharge Current ◽  
Fuzzy Model ◽  
Constant Load ◽  
Operating Parameters ◽  
Half Cycle ◽  
Wear Process ◽  
Nickel Manganese ◽  
Load Conditions

This article describes the analyses of modeling the wear process of lithium-nickel-manganese-cobalt cells operating cyclically under constant load conditions. The main aging processes taking place in cells and the methodology of the modeling are discussed. The process of cell wear is examined, taking into account the influence of cyclic operating parameters (temperature, discharge current, and discharge depth). On the basis of the analyses carried out, a new function reflecting the influence of ambient temperature on the durability of the cell is proposed. A new fuzzy model of the wear process of the NMC 18650 type cell, depending on the parameters of the discharge half cycle, has been developed. The results of the model have been verified by experimental research.

scholarly journals Cold start emissions from a gasoline engine in RDE tests at different ambient temperatures

2020 ◽  
Vol 181 (2) ◽  
pp. 24-30
Author(s):  
Karolina KURTYKA ◽  
Jacek PIELECHA
Keyword(s):  
Ambient Temperature ◽  
Gasoline Engine ◽  
Test Procedure ◽  
Cold Start ◽  
Exhaust Emissions ◽  
Test Method ◽  
Exhaust Emission ◽  
Operating Parameters ◽  
Passenger Cars ◽  
Ambient Temperatures

The implementation of the 3rd package of the RDE test procedure has extended the test method by considering emissions from a cold start period into the total exhaust emissions from a vehicle. The article presents the research results of exhaust emissions of a vehicle equipped with a gasoline engine. The tests were carried out at two different ambient temperatures, in line with the requirements of the RDE test procedure for passenger cars, meeting the Euro 6d-Temp emissions standard. The obtained results were analyzed, i.e. there were compared the engine and vehicle operating parameters and the values of road exhaust emissions during the cold start at two different ambient temperatures. The summary presents the shares of the cold start phase for each exhaust emission compound in the urban part of the test and the entire RDE test, depending on the ambient temperature (8ºC and 25ºC).

Application of Improved Voltage Compensation in the SEM to Imaging of Organic Materials

1973 ◽  
Vol 31 ◽  
pp. 444-445
Author(s):  
P.J. Killingworth ◽  
M. Warren
Keyword(s):  
Electron Beam ◽  
Organic Materials ◽  
Operating Parameters ◽  
Low Density ◽  
Beam Diameter ◽  
Incident Electron Beam ◽  
Specimen Material ◽  
Voltage Compensation ◽  
Selection Of ◽  
Scanning Electron

Ultimate resolution in the scanning electron microscope is determined not only by the diameter of the incident electron beam, but by interaction of that beam with the specimen material. Generally, while minimum beam diameter diminishes with increasing voltage, due to the reduced effect of aberration component and magnetic interference, the excited volume within the sample increases with electron energy. Thus, for any given material and imaging signal, there is an optimum volt age to achieve best resolution.In the case of organic materials, which are in general of low density and electric ally non-conducting; and may in addition be susceptible to radiation and heat damage, the selection of correct operating parameters is extremely critical and is achiev ed by interative adjustment.

SEM of non-coated hepatocellular cytoskeleton of perfused livers

1984 ◽  
Vol 42 ◽  
pp. 306-307
Author(s):  
S.W. French ◽  
N.C. Benson ◽  
C. Davis-Scibienski
Keyword(s):  
Ambient Temperature ◽  
Critical Point ◽  
Protease Inhibitors ◽  
Metal Deposition ◽  
Heat Damage ◽  
Detergent Extraction ◽  
Cytoskeletal Elements ◽  
Triton X ◽  
Excised Tissue

Previous SEM studies of liver cytoskeletal elements have encountered technical difficulties such as variable metal coating and heat damage which occurs during metal deposition. The majority of studies involving evaluation of the cell cytoskeleton have been limited to cells which could be isolated, maintained in culture as a monolayer and thus easily extracted. Detergent extraction of excised tissue by immersion has often been unsatisfactory beyond the depth of several cells. These disadvantages have been avoided in the present study. Whole C3H mouse livers were perfused in situ with 0.5% Triton X-100 in a modified Jahn's buffer including protease inhibitors. Perfusion was continued for 1 to 2 hours at ambient temperature. The liver was then perfused with a 2% buffered gluteraldehyde solution. Liver samples including spontaneous tumors were then maintained in buffered gluteraldehyde for 2 hours. Samples were processed for SEM and TEM using the modified thicarbohydrazide procedure of Malich and Wilson, cryofractured, and critical point dried (CPD). Some samples were mechanically fractured after CPD.

Formation of Dislocation Channels in Neutron Irradiated Molybdenum

1972 ◽  
Vol 30 ◽  
pp. 672-673
Author(s):  
S. Mahajan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ambient Temperature ◽  
Room Temperature ◽  
Channel Formation ◽  
Early Stages ◽  
Transmission Electron ◽  
Three Stages ◽  
Two Stages ◽  
Polycrystalline Molybdenum

The evolution of dislocation channels in irradiated metals during deformation can be envisaged to occur in three stages: (i) formation of embryonic cluster free regions, (ii) growth of these regions into microscopically observable channels and (iii) termination of their growth due to the accumulation of dislocation damage. The first two stages are particularly intriguing, and we have attempted to follow the early stages of channel formation in polycrystalline molybdenum, irradiated to 5×1019 n. cm−2 (E > 1 Mev) at the reactor ambient temperature (∼ 60°C), using transmission electron microscopy. The irradiated samples were strained, at room temperature, up to the macroscopic yield point.Figure 1 illustrates the early stages of channel formation. The observations suggest that the cluster free regions, such as A, B and C, form in isolated packets, which could subsequently link-up to evolve a channel.

Crystallographic Characterization of Dislocation Loops in Irradiated Tungsten

1968 ◽  
Vol 26 ◽  
pp. 290-291
Author(s):  
Robert C. Rau
Keyword(s):  
Electron Microscope ◽  
Ambient Temperature ◽  
Dislocation Loops ◽  
Polycrystalline Specimen ◽  
Post Irradiation ◽  
Neutron Fluences

Previous work has shown that post-irradiation annealing, at temperatures near 1100°C, produces resolvable dislocation loops in tungsten irradiated to fast (E > 1 MeV) neutron fluences of about 4 x 1019 n/cm2 or greater. To crystallographically characterize these loops, tilting experiments were carried out in the electron microscope on a polycrystalline specimen which had been irradiated to 1.5 × 1021 n/cm2 at reactor ambient temperature (∼ 70°C), and subseouently annealed for 315 hours at 1100°C. This treatment produced large loops averaging 1000 Å in diameter, as shown in the micrographs of Fig. 1. The orientation of this grain was near (001), and tilting was carried out about axes near [100], [10] and [110].

Voids in Quenched Nickel

1968 ◽  
Vol 26 ◽  
pp. 266-267
Author(s):  
J. J. Laidler
Keyword(s):  
Electron Beam ◽  
Ambient Temperature ◽  
Cooling Rate ◽  
Three Dimensional ◽  
Cooling Curve ◽  
Polycrystalline Nickel ◽  
Quenching Temperature ◽  
Long Tail ◽  
Diffusion Pump

The presence of three-dimensional voids in quenched metals has long been suspected, and voids have indeed been observed directly in a number of metals. These include aluminum, platinum, and copper, silver and gold. Attempts at the production of observable quenched-in defects in nickel have been generally unsuccessful, so the present work was initiated in order to establish the conditions under which such defects may be formed.Electron beam zone-melted polycrystalline nickel foils, 99.997% pure, were quenched from 1420°C in an evacuated chamber into a bath containing a silicone diffusion pump fluid . The pressure in the chamber at the quenching temperature was less than 10-5 Torr . With an oil quench such as this, the cooling rate is approximately 5,000°C/second above 400°C; below 400°C, the cooling curve has a long tail. Therefore, the quenched specimens are aged in place for several seconds at a temperature which continuously approaches the ambient temperature of the system.

Electron sources: Past, present, and future

1993 ◽  
Vol 51 ◽  
pp. 764-765
Author(s):  
David C Joy
Keyword(s):  
Glass Tube ◽  
Source Size ◽  
Electron Gun ◽  
Operating Parameters ◽  
Operational Parameters ◽  
Electron Sources ◽  
Difficult Decision ◽  
Probe Size ◽  
Wide Range ◽  
Overall Performance

The electron source is the most important component of the Scanning electron microscope (SEM) since it is this which will determine the overall performance of the machine. The gun performance can be described in terms of quantities such as its brightness, its source size, its energy spread, and its stability and, depending on the chosen application, any of these factors may be the most significant one. The task of the electron gun in an SEM is, in fact, particularly difficult because of the very wide range of operational parameters that may be required e.g a variation in probe size of from a few angstroms to a few microns, and a probe current which may go from less than a pico-amp to more than a microamp. This wide range of operating parameters makes the choice of the optimum source for scanning microscopy a difficult decision.Historically, the first step up from the sealed glass tube ‘cathode ray generator’ was the simple, diode, tungsten thermionic emitter.

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