BURNING OF A MIXTURE OF LIQUID KEROSENE AND COLD AIR IN A DETONATION CHAMBER 503 MM IN DIAMETER WITH CHAMBER GEOMETRY VARIATION

2020 ◽  
Author(s):  
F. A. BYKOVSKII ◽  
◽  
S. A. ZHDAN ◽  
E. F. VEDERNIKOV ◽  
◽  
...  
Keyword(s):  
Diesel Oil ◽  
Cold Air ◽  
Flow Type ◽  
Significant Interest ◽  
Isopropyl Nitrate ◽  
First Time

Investigations of detonative combustion of kerosene in air in flow-type combustors are of significant interest for science and applications. Detonative combustion of cold kerosene and diesel oil was earlier reached for the first time in a plane-radial combustor with a diameter dc1 = 204 mm. In annular cylindrical combustors, detonative combustion was obtained only if air was enriched with oxygen or if kerosene was enriched with hydrogen; another possible option was addition of isopropyl nitrate to kerosene.

Ambient vibration test results of the Imperial County Services Building

1983 ◽  
Vol 73 (6A) ◽  
pp. 1895-1902
Author(s):  
Gerard C. Pardoen
Keyword(s):  
Strong Motion ◽  
Ambient Vibration ◽  
Vibration Test ◽  
Test Results ◽  
Structural Failure ◽  
Imperial Valley ◽  
Ambient Vibration Test ◽  
Significant Interest ◽  
First Time ◽  
County Services

Abstract The ambient vibration test results conducted on the Imperial County Services Building prior to the 15 October 1979 Imperial Valley earthquake are summarized. These results are of significant interest because the Imperial County Services Building has been the source of many postearthquake investigations due to the fact that the 1979 earthquake represented the first time a building instrumented with strong motion recorders suffered and recorded the major structural failure.

Instrumentation Improvements for the Leak Detection and Batch Tracking Systems of the Sa˜o Paulo Brasi´lia Pipeline (OSBRA)

2008 ◽  
Author(s):  
Ma´rcio Manha˜es Gomes de Almeida ◽  
Jose Augusto Morais de Andrade ◽  
Andre Paulo Kotchetkoff Neto
Keyword(s):  
Detection System ◽  
Leak Detection ◽  
Diesel Oil ◽  
Flow Measurements ◽  
Control Center ◽  
Tank Farm ◽  
Field Instrumentation ◽  
Pumping Stations ◽  
Actual Field ◽  
First Time

OSBRA is the 964 Km pipeline which supplies over 6.500.000 m3/year of gasoline, diesel oil and LPG to the Brazilian Midwestern region. Products on OSBRA pipeline are pumped 24 hours a day and 365 days a year on a scheduled basis from Planalto Paulista Refinery – REPLAN to 5 midsize cities through 6 remote operated pumping stations located along the pipeline. The pipeline operation, including pumping and valve actuations and tank farm monitoring, is done remotely from PETROBRAS Transporte S/A – TRANSPETRO National Pipeline Control Center (CNCO). A real time leak detection system (LDS) was supplied and installed at the CNCO. The LDS is based on measurements of flow and pressure as well as pump and valve status along the pipeline. An actual field leak test was done in order to validate and verify the LDS performance. The LDS performance was considered satisfactory at the first time, but after a few months an excessive number of false leak alarms started to occur. A detailed investigation was conducted both on operational procedures and field instrument installation. This report shows how this investigation was conducted and the main recommendations that were agreed in order to avoid the LDS to detract from credibility and the creation of complacency. It is presented the existing limitations on the flow measurements and the improvements that are planned to field instrumentation, operational/maintenance procedures and the OSBRA LDS and Batch Tracking models so it could reach a higher performance level.

scholarly journals Report for Maintenance Air Cooled Chiller Power Ciat 2800X

2020 ◽  
Vol 4 (2) ◽  
pp. 42-50
Author(s):  
Rasheed N. Abed ◽  
Ramzi Qasim Muhammed
Keyword(s):  
Water Temperature ◽  
Ball Bearing ◽  
Cooling Capacity ◽  
Air Cooling ◽  
Planning Study ◽  
Cold Air ◽  
Air Handling Units ◽  
Chilled Water ◽  
Student Club ◽  
First Time

In this report, the maintenance of the chiller ciat to feed the cooling capacity of the presidency of Al-Nahrain University and the student club buildings was achieved. The chiller ciat was repaired and operated by using the planning study for the maintenance and complete all faults that leads to stop the chiller from working. The results for repairing are very good and the chilled water temperature is (7 oC) to feed the air handling units, which gives the cold air inside the building to all facilities such as (offices, and hallways). According to the maintenance of the chiller ciat was utilized the best material and with cheap prices, which were brought from the local markets, such as: gat valve to open/close the chilled water that exit from the evaporator to the pumps, air vents, filters, ball bearing type (NSK-Poland) and it size was (6005Z). For repairing the package unit of the computerize center in the student club building was invented a new method that leads to cool this place with facilities such as (offices, and hallways). A better performance was achieved for the output chilled water from the chiller and the air handling units are able to give a cooled air to all facilities inside the buildings. This report is one of the first maintenance studies to repair the chiller ciat with these problems in very hot atmosphere. Where is utilized some procedure for the first time to prepare the air cooling for all offices in buildings.

scholarly journals A Grain-Scale Study of Mojave Mars Simulant (MMS-1)

Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4730
Author(s):  
Sathwik S. Kasyap ◽  
Kostas Senetakis
Keyword(s):  
Surface Composition ◽  
Space Exploration ◽  
Severe Damage ◽  
Geotechnical Characteristics ◽  
Significant Interest ◽  
Natural Satellites ◽  
Individual Grains ◽  
Crushing Behavior ◽  
First Time ◽  
Particle Configuration

Space exploration has attracted significant interest by government agencies and the scientific community in recent years in an attempt to explore possible scenarios of settling of facilities on the Moon and Mars surface. One of the important components in space exploration is related with the understanding of the geophysical and geotechnical characteristics of the surfaces of planets and their natural satellites and because of the limitation of available extra-terrestrial samples, many times researchers develop simulants, which mimic the properties and characteristics of the original materials. In the present study, characterization at the grain-scale was performed on the Mojave Mars Simulant (MMS-1) with emphasis on the frictional behavior of small size samples which follow the particle-to-particle configuration. Additional characterization was performed by means of surface composition and morphology analysis and the crushing behavior of individual grains. The results from the study present for the first time the micromechanical tribological response of Mars simulant, and attempts were also made to compare the behavior of this simulant with previously published results on other types of Earth and extra-terrestrial materials. Despite some similarities between Mars and Moon simulants, the unique characteristics of the MMS-1 samples resulted in significant differences and particularly in severe damage of the grain surfaces, which was also linked to the dilation behavior at the grain-scale.

Annulate lamellae in the Sertoli cells of guinea pig testis after unilateral torsion of the spermatic cord

1984 ◽  
Vol 42 ◽  
pp. 196-197
Author(s):  
J. Chakraborty ◽  
A. P. Sinha Hikim ◽  
J. S. Jhunjhunwala
Keyword(s):  
Sertoli Cells ◽  
Guinea Pigs ◽  
Spermatic Cord ◽  
Present Report ◽  
Cell Types ◽  
Annulate Lamellae ◽  
Spermatogenic Cells ◽  
Electron Microscopic ◽  
Structural Details ◽  
First Time

Although the presence of annulate lamellae was noted in many cell types, including the rat spermatogenic cells, this structure was never reported in the Sertoli cells of any rodent species. The present report is based on a part of our project on the effect of torsion of the spermatic cord to the contralateral testis. This paper describes for the first time, the fine structural details of the annulate lamellae in the Sertoli cells of damaged testis from guinea pigs.One side of the spermatic cord of each of six Hartly strain adult guinea pigs was surgically twisted (540°) under pentobarbital anesthesia (1). Four months after induction of torsion, animals were sacrificed, testes were excised and processed for the light and electron microscopic investigations. In the damaged testis, the majority of seminiferous tubule contained a layer of Sertoli cells with occasional spermatogonia (Fig. 1). Nuclei of these Sertoli cells were highly pleomorphic and contained small chromatinic clumps adjacent to the inner aspect of the nuclear envelope (Fig. 2).

Electron spectroscopic imaging and diffraction

1991 ◽  
Vol 49 ◽  
pp. 706-707
Author(s):  
M. Rühle ◽  
J. Mayer ◽  
J.C.H. Spence ◽  
J. Bihr ◽  
W. Probst ◽  
...  
Keyword(s):  
Materials Science ◽  
Electron Spectroscopic Imaging ◽  
Magnetic Filter ◽  
Magnetic Imaging ◽  
Illumination System ◽  
Probe Size ◽  
Diffraction Patterns ◽  
Fritz Haber ◽  
Koehler Illumination ◽  
First Time

A new Zeiss TEM with an imaging Omega filter is a fully digitized, side-entry, 120 kV TEM/STEM instrument for materials science. The machine possesses an Omega magnetic imaging energy filter (see Fig. 1) placed between the third and fourth projector lens. Lanio designed the filter and a prototype was built at the Fritz-Haber-Institut in Berlin, Germany. The imaging magnetic filter allows energy-filtered images or diffraction patterns to be recorded without scanning using efficient area detection. The energy dispersion at the exit slit (Fig. 1) results in ∼ 1.5 μm/eV which allows imaging with energy windows of ≤ 10 eV. The smallest probe size of the microscope is 1.6 nm and the Koehler illumination system is used for the first time in a TEM. Serial recording of EELS spectra with a resolution < 1 eV is possible. The digital control allows X,Y,Z coordinates and tilt settings to be stored and later recalled.

A Novel TEM Technique for Characterizing As-Grown CVD Diamond Films

1991 ◽  
Vol 49 ◽  
pp. 956-957 ◽  
Author(s):  
Z.L. Wang ◽  
J. Bentley ◽  
R.E. Clausing ◽  
L. Heatherly ◽  
L.L. Horton
Keyword(s):  
Diamond Films ◽  
Chemical Vapor ◽  
Growth Direction ◽  
Dark Field ◽  
Growth Surface ◽  
Specimen Preparation ◽  
Transmission Electron ◽  
Diffraction Patterns ◽  
First Time ◽  
Microstructural Studies

Microstructural studies by transmission electron microscopy (TEM) of diamond films grown by chemical vapor deposition (CVD) usually involve tedious specimen preparation. This process has been avoided with a technique that is described in this paper. For the first time, thick as-grown diamond films have been examined directly in a conventional TEM without thinning. With this technique, the important microstructures near the growth surface have been characterized. An as-grown diamond film was fractured on a plane containing the growth direction. It took about 5 min to prepare a sample. For TEM examination, the film was tilted about 30-45° (see Fig. 1). Microstructures of the diamond grains on the top edge of the growth face can be characterized directly by transmitted electron bright-field (BF) and dark-field (DF) images and diffraction patterns.

A microscopic marker experiment study on high temperature oxidation of Ni-Al alloy

1986 ◽  
Vol 44 ◽  
pp. 514-515
Author(s):  
Shou-kong Fan
Keyword(s):  
Transport Mechanism ◽  
High Temperature Oxidation ◽  
Transverse Section ◽  
Al Alloy ◽  
Metal Interface ◽  
Electron Microscopic ◽  
Temperature Oxidation ◽  
Analytical Electron ◽  
Microscopic Studies ◽  
First Time

Transmission and analytical electron microscopic studies of scale microstructures and microscopic marker experiments have been carried out in order to determine the transport mechanism in the oxidation of Ni-Al alloy. According to the classical theory, the oxidation of nickel takes place by transport of Ni cations across the scale forming new oxide at the scale/gas interface. Any markers deposited on the Ni surface are expected to remain at the scale/metal interface after oxidation. This investigation using TEM transverse section techniques and deposited microscopic markers shows a different result,which indicates that a considerable amount of oxygen was transported inward. This is the first time that such fine-scale markers have been coupled with high resolution characterization instruments such as TEM/STEM to provide detailed information about evolution of oxide scale microstructure.

Direct imaging of charge transfer

1996 ◽  
Vol 54 ◽  
pp. 680-681
Author(s):  
Yimei Zhu ◽  
J. Tafto
Keyword(s):  
Charge Transfer ◽  
Electron Diffraction ◽  
Scattering Amplitude ◽  
High Temperature Superconductors ◽  
Charge Carriers ◽  
Image Charge ◽  
Net Charge ◽  
Long Time ◽  
Electron Holes ◽  
First Time

The electron holes confined to the CuO2-plane are the charge carriers in high-temperature superconductors, and thus, the distribution of charge plays a key role in determining their superconducting properties. While it has been known for a long time that in principle, electron diffraction at low angles is very sensitive to charge transfer, we, for the first time, show that under a proper TEM imaging condition, it is possible to directly image charge in crystals with a large unit cell. We apply this new way of studying charge distribution to the technologically important Bi2Sr2Ca1Cu2O8+δ superconductors.Charged particles interact with the electrostatic potential, and thus, for small scattering angles, the incident particle sees a nuclei that is screened by the electron cloud. Hence, the scattering amplitude mainly is determined by the net charge of the ion. Comparing with the high Z neutral Bi atom, we note that the scattering amplitude of the hole or an electron is larger at small scattering angles. This is in stark contrast to the displacements which contribute negligibly to the electron diffraction pattern at small angles because of the short g-vectors.

Recent developments in low-voltage SEM of polymers

1993 ◽  
Vol 51 ◽  
pp. 866-867
Author(s):  
S.J. Krause ◽  
W.W. Adams
Keyword(s):  
Low Voltage ◽  
Chromatic Aberration ◽  
Thermal Electron ◽  
Analytical Technique ◽  
Recent Developments ◽  
Beam Currents ◽  
New Generation ◽  
First Time ◽  
Voltage Scanning ◽  
Beam Damage

Over the past decade low voltage scanning electron microscopy (LVSEM) of polymers has evolved from an interesting curiosity to a powerful analytical technique. This development has been driven by improved instrumentation and in particular, reliable field emission gun (FEG) SEMs. The usefulness of LVSEM has also grown because of an improved theoretical and experimental understanding of sample-beam interactions and by advances in sample preparation and operating techniques. This paper will review progress in polymer LVSEM and present recent results and developments in the field.In the early 1980s a new generation of SEMs produced beam currents that were sufficient to allow imaging at low voltages from 5keV to 0.5 keV. Thus, for the first time, it became possible to routinely image uncoated polymers at voltages below their negative charging threshold, the "second crossover", E2 (Fig. 1). LVSEM also improved contrast and reduced beam damage in sputter metal coated polymers. Unfortunately, resolution was limited to a few tenths of a micron due to the low brightness and chromatic aberration of thermal electron emission sources.

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