ELECTRON-STIMULATED DESORPTION OF POTASSIUM ATOMS ADSORBED ON THE SURFACE OF GOLD

Physical and Chemical Aspects of the Study of Clusters Nanostructures and Nanomaterials ◽

10.26456/pcascnn/2020.12.836 ◽

2020 ◽

pp. 836-844

Author(s):

Юрий Александрович Кузнецов ◽

Михаил Николаевич Лапушкин

Keyword(s):

Intermetallic Compound ◽

Excitation Energy ◽

Room Temperature ◽

Intermetallic Layer ◽

Gold Layer ◽

The Core ◽

Tungsten Surface ◽

Electron Stimulated Desorption

Создан ультратонкий слой интерметаллида KAu при комнатной температуре при напылении атомов калия на слой адсорбированного золота на поверхности вольфрама. Исследованы процессы электронно-стимулированной десорбции атомов K с поверхности KAu. Найдены квазирезонансные пики в зависимости выхода ЭСД от энергии возбуждения при 64 и 82 эВ, которые соответствуют возбуждению остовных уровней Au 5р и Au 5р. Полученные результаты свидетельствуют о формировании KAu различной стехиометрии: от KAu до KAu. Показано, что интерметаллид KAu, полученный при комнатной температуре, как полученный ранее KAu при 1000K, является полупроводником. Предложена модель электронно-стимулированной десорбции атомов K в системе K/KAu/Au/W. An ultrathin intermetallic layer KAuwas created at room temperature by depositing potassium atoms on adsorbed gold layer on the tungsten surface. The processes of electron-stimulated desorption of K atoms from the KAu surface are investigated. Quasi-resonance peaks are found in the dependence of the ESD yield on the excitation energy at 64 and 82 eV, which correspond to the excitation of the core levels Au 5p and Au 5p. The obtained results indicate the formation KAu of different stoichiometry: from KAu to KAu . It is shown that the intermetallic compound KAu created at room temperature is a semiconductor, as it was previously obtained at 1000 K. A model of electron-stimulated desorption of K atoms in the K / KAu / Au / W system is proposed.

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ELECTRON-STIMULATED DESORPTION OF LITHIUM ATOMS ADSORBED ON THE SURFACE OF GOLD-LITHIUM INTERMETALLIC

Physical and Chemical Aspects of the Study of Clusters Nanostructures and Nanomaterials ◽

10.26456/pcascnn/2021.13.235 ◽

2021 ◽

pp. 235-242

Author(s):

Юрий Александрович Кузнецов ◽

Михаил Николаевич Лапушкин

Keyword(s):

Thin Film ◽

Intermetallic Compound ◽

Kinetic Energy ◽

Energy Distribution ◽

Room Temperature ◽

High Energy ◽

Low Energy ◽

Tungsten Surface ◽

Electron Stimulated Desorption ◽

Two Peaks

Получена тонкая пленка интерметаллида LiAu при комнатной температуре при напылении атомов Li на слой адсорбированного золота на поверхности вольфрама. Исследованы процессы электронно-стимулированной десорбции (ЭСД) атомов Li с поверхности LiAu. Показано, что ЭСД атомов Li может наблюлаться только в том случае, когда напылено не менее одного монослоя атомов Li и с Au . Зависимость выхода ЭСД атомов Li от количества напыленного Li и Au имеет максимум при напылении двух монослоев атомов Li на Au. Полученные результаты свидетельствуют о формировании LiAu различной стехиометрии: от LiAu с дефицитом атомов лития до LiAu при напылении двух монослоев атомов Li. В энергетическом распределении по кинетическим энергиям десорбирующихся атомов Li обнаружено два пика: высокоэнергетический и низкоэнергетический. Первый из них связан с десорбцией атомов Li из LiAu, а второй в десорбцией атомов Li из верхнего монослоя атомов Li. A thin film of the intermetallic compound LiAu was obtained at room temperature by deposition Li atoms onto a layer of adsorbed gold on the tungsten surface. The processes of electron-stimulated desorption of Li atoms from the surface are investigated. It is shown that electron-stimulated desorption of Li atoms can be observed only in the case when at least one monolayer of Li and Au atoms is deposited. The dependence of the electron-stimulated desorption yield of Li atoms on the amount of deposited has a maximum when two monolayers of atoms Li are deposited on Au . The results obtained indicate the LiAu formation of various stoichiometry: from with a deficit of lithium atoms to the deposition of two monolayers of atoms. In the kinetic energy distribution of desorbed Li atoms, two peaks were found: high-energy and low-energy. The first of them is associated with the desorption of Li atoms from LiAu, and the second with the desorption of Li atoms from the upper monolayer of Li atoms.

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Design of Swimming Pool Temperature Dot Matrix Screen Display

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.556-562.2208 ◽

2014 ◽

Vol 556-562 ◽

pp. 2208-2211

Author(s):

Xue Feng Yang

Keyword(s):

Water Temperature ◽

Real Time ◽

Room Temperature ◽

Detection Method ◽

Swimming Pool ◽

Real Time Monitoring ◽

Real Time Processing ◽

The Core ◽

Swimming Pool Water ◽

Point Detection

According to the need of the real-time monitoring and displaying of the environment in many areas,to put forward a method of temperature monitoring and displaying, using STC11F32XE microcontroller as the core controller, DS18B20 as temperature acquisition chip, 32X64LED dot matrix screen as a display screen,using the mothod of multi point detection method,real-time monitoring of swimming pool water temperature and room temperature, real-time displaying of Multipoint collecting information, Real time processing the detected temperature, the page display to multipoint temperature display through the wireless remote control module,the system will alarm When the water temperature is too high or too low, to remind managers of real-time processing.To design a clear temperature display for the swimming pool,real time monitoring and controlling is very convenient,after the experimental verification, the system reaches the anticipative goal,the system is an ideal and effective.

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Growth of Listeria monocytogenes within a Caramel-Coated Apple Microenvironment

mBio ◽

10.1128/mbio.01232-15 ◽

2015 ◽

Vol 6 (5) ◽

Cited By ~ 31

Author(s):

Kathleen A. Glass ◽

Max C. Golden ◽

Brandon J. Wanless ◽

Wendy Bedale ◽

Charles Czuprynski

Keyword(s):

Listeria Monocytogenes ◽

Water Activity ◽

Room Temperature ◽

Slow Growth ◽

Free Water ◽

Storage Conditions ◽

Pathogenic Bacterium ◽

Content Type ◽

The Core ◽

Serotype 4B

ABSTRACT A 2014 multistate listeriosis outbreak was linked to consumption of caramel-coated apples, an unexpected and previously unreported vehicle for Listeria monocytogenes. This outbreak was unanticipated because both the pH of apples (<4.0) and the water activity of the caramel coating (<0.80) are too low to support Listeria growth. In this study, Granny Smith apples were inoculated with approximately 4 log10 CFU of L. monocytogenes (a cocktail of serotype 4b strains associated with the outbreak) on each apple's skin, stem, and calyx. Half of the apples had sticks inserted into the core, while the remaining apples were left intact. Apples were dipped into hot caramel and stored at either 7°C or 25°C for up to 11 or 28 days, respectively. Data revealed that apples with inserted sticks supported significantly more L. monocytogenes growth than apples without sticks under both storage conditions. Within 3 days at 25°C, L. monocytogenes populations increased >3 log10 in apples with sticks, whereas only a 1-log10 increase was observed even after 1 week for caramel-coated apples without sticks. When stored at 7°C, apples with sticks exhibited an approximately 1.5-log10 increase in L. monocytogenes levels at 28 days, whereas no growth was observed in apples without sticks. We infer that insertion of a stick into the apple accelerates the transfer of juice from the interior of the apple to its surface, creating a microenvironment at the apple-caramel interface where L. monocytogenes can rapidly grow to levels sufficient to cause disease when stored at room temperature. IMPORTANCE Neither caramel nor apples are a food where the pathogenic bacterium Listeria monocytogenes should grow, as caramel does not contain enough free water and apples are too acidic. Caramel-coated apples, however, were recently linked to a deadly outbreak of listeriosis. We hypothesized that inserting a stick into the apple releases juice to the interface between the apple and caramel, providing a more hospitable environment than either component alone. To test this hypothesis, apples were inoculated with L. monocytogenes prior to caramel dipping. Some apples had sticks inserted into them before dipping, while others did not. No growth of L. monocytogenes occurred on refrigerated caramel apples without sticks, whereas slow growth was observed on refrigerated caramel apples with sticks. In contrast, significant pathogen growth was observed within 3 days at room temperature on caramel apples with sticks inserted. Food producers should consider interfaces between components within foods as potential niches for pathogen growth.

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The CORE Sequence: A Nanoscale Fluorocarbon-Free Silicon Plasma Etch Process Based on SF6/O2 Cycles with Excellent 3D Profile Control at Room Temperature

ECS Journal of Solid State Science and Technology ◽

10.1149/2162-8777/ab61ed ◽

2020 ◽

Vol 9 (2) ◽

pp. 024002 ◽

Cited By ~ 3

Author(s):

Vy Thi Hoang Nguyen ◽

Chantal Silvestre ◽

Peixiong Shi ◽

Roy Cork ◽

Flemming Jensen ◽

...

Keyword(s):

Room Temperature ◽

Plasma Etch ◽

The Core ◽

Core Sequence ◽

Free Silicon ◽

Profile Control ◽

3D Profile

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High-Temperature Fatigue Properties of Single Crystal Superalloys in Air and Hydrogen

Volume 4: Manufacturing Materials and Metallurgy; Ceramics; Structures and Dynamics; Controls, Diagnostics and Instrumentation; Education; IGTI Scholar Award ◽

10.1115/2001-gt-0585 ◽

2001 ◽

Cited By ~ 3

Author(s):

Nagaraj K. Arakere

Keyword(s):

High Pressure ◽

Shear Stress ◽

High Temperature ◽

Fatigue Life ◽

Single Crystal ◽

Room Temperature ◽

Turbine Blades ◽

The Core ◽

Blade Tip ◽

Pressure Hydrogen

Hot section components in high performance aircraft and rocket engines are increasingly being made of single crystal nickel superalloys such as PWA1480, PWA1484, CMSX-4 and Rene N-4 as these materials provide superior creep, stress rupture, melt resistance and thermomechanical fatigue capabilities over their polycrystalline counterparts. Fatigue failures in PWA1480 single crystal nickel-base superalloy turbine blades used in the Space Shuttle Main Engine (SSME) fuel turbopump are discussed. During testing many turbine blades experienced Stage II non-crystallographic fatigue cracks with multiple origins at the core leading edge radius and extending down the airfoil span along the core surface. The longer cracks transitioned from stage II fatigue to crystallographic stage I fatigue propagation, on octahedral planes. An investigation of crack depths on the population of blades as a function of secondary crystallographic orientation (β) revealed that for β = 45+/- 15 degrees tip cracks arrested after some growth or did not initiate at all. Finite element analysis of stress response at the blade tip, as a function of primary and secondary crystal orientation, revealed that there are preferential β orientations for which crack growth is minimized at the blade tip. To assess blade fatigue life and durability extensive testing of uniaxial single crystal specimens with different orientations has been tested over a wide temperature range in air and hydrogen. A detailed analysis of the experimentally determined Low Cycle Fatigue (LCF) properties for PWA1480 and SC 7-14-6 single crystal materials as a function of specimen crystallographic orientation is presented at high temperature (75 F – 1800 F) in high-pressure hydrogen and air. Fatigue failure parameters are investigated for LCF data of single crystal material based on the shear stress amplitudes on the 24 octahedral and 6 cube slip systems for FCC single crystals. The max shear stress amplitude [Δτmax] on the slip planes reduces the scatter in the LCF data and is found to be a good fatigue damage parameter, especially at elevated temperatures. The parameter Δτmax did not characterize the room temperature LCF data in high-pressure hydrogen well because of the noncrystallographic eutectic failure mechanism activated by hydrogen at room temperature. Fatigue life equations are developed for various temperature ranges and environmental conditions based on power-law curve fits of the failure parameter with LCF test data. These curve fits can be used for assessing blade fatigue life.

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Synthesis and Magnetic Properties of CoAl2O4 Coated Co Solid Solution Nanocapsules

Materials Science Forum ◽

10.4028/www.scientific.net/msf.663-665.1256 ◽

2010 ◽

Vol 663-665 ◽

pp. 1256-1259

Author(s):

Gui Mei Shi ◽

Ge Song ◽

Shu Lian ◽

Jin Bing Zhang

Keyword(s):

Solid Solution ◽

Photoelectron Spectrum ◽

Room Temperature ◽

Ferromagnetic State ◽

Antiferromagnetic Order ◽

X Ray Diffraction ◽

X Ray ◽

The Core ◽

New Type ◽

The Magnetic Field

A new type of antiferromagnetic CoAl2O4 coated ferromagnetic Co solid solution is synthesized by arc-discharging. Typical HRTEM images show that the nanocapsules form in a core-shell structure. The size of the nanocapsules is in range of 10-90 nm and the thickness of the shell is about 3-10 nm. X-ray photoelectron spectrum (XPS) and X-ray diffraction (XRD) reveal that the core consists of Co solid solution, while the shell is CoAl2O4. The magnetic field and temperature dependence of magnetizations confirm that the Co solid solution nanocapsules are basically in the ferromagnetic state below Curie temperature. In addition, the antiferromagnetic order occurs with Neél temperature TN of about 5 K. The saturation magnetization of Ms = 76.1 Am2/kg and the coercive force of Hc= 23.28 kA/m are achieved at room temperature for the Co solid solution nanocapsules.

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Formation of the intermetallic compound PtZn at room temperature

Acta Metallurgica ◽

10.1016/0001-6160(55)90075-4 ◽

1955 ◽

Vol 3 (3) ◽

pp. 302-304 ◽

Cited By ~ 8

Author(s):

H.H. Uhlig ◽

J.S. MacNairn ◽

D.A. Vaughn

Keyword(s):

Intermetallic Compound ◽

Room Temperature

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Identification of Nanocrystalline Inclusions in Bismuth-Doped Silica Fibers and Preforms

Microscopy and Microanalysis ◽

10.1017/s1431927616011569 ◽

2016 ◽

Vol 22 (5) ◽

pp. 987-996 ◽

Cited By ~ 7

Author(s):

Liudmila D. Iskhakova ◽

Filipp O. Milovich ◽

Valery M. Mashinsky ◽

Alexander S. Zlenko ◽

Sergey E. Borisovsky ◽

...

Keyword(s):

Optical Fibers ◽

Room Temperature ◽

Optical Loss ◽

Laser Generation ◽

Dopant Distribution ◽

X Ray ◽

The Core ◽

Silica Fibers ◽

Transmission Electron ◽

Bismuth Concentration

AbstractThe nature of nanocrystalline inclusions and dopant distribution in bismuth-doped silicate fibers and preforms are studied by scanning and transmission electron microscopy, and energy and wavelength-dispersive X-ray microanalysis. The core compositions are Bi:SiO2, Bi:Al2O3–SiO2, Bi:GeO2–SiO2, Bi:Al2O3–GeO2–SiO2, and Bi:P2O5–Al2O3–GeO2–SiO2. Nanocrystals of metallic Bi, Bi2O3, SiO2, GeO2, and Bi4(GeO4)3 are observed in these glasses. These inclusions can be the reason for the background optical loss in bismuth-doped optical fibers. The bismuth concentration of 0.0048±0.0006 at% is directly measured in aluminosilicate optical fibers with effective laser generation (slope efficiency of 27% at room temperature).

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Investigation of the Intermetallic Formation on Wet Underwater Welding of AISI 4012 Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.991.10 ◽

2020 ◽

Vol 991 ◽

pp. 10-16

Author(s):

Agus Dwi Anggono ◽

Suwantri ◽

Waluyo Adi Siswanto ◽

Joko Sedyono

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Intermetallic Compound ◽

Tensile Test ◽

Electric Current ◽

Intermetallic Layer ◽

Plain Water ◽

Water Pool ◽

Underwater Welding ◽

Intermetallic Formation

The objectives of the study is to investigate the formation of intermetallic compound and the mechanical properties of the underwater welding. AISI 4012 steel was selected as the material and two types of electrode E6013 and E7018. The variations of electric current used in this study were 80,100, and 120 amperes. The underwater welding was conducted in plain water pool and 3 meters depth by using SMAW. Tensile test and SEM-EDS were carried out to investigate the tensile strength and appearence the intermetallic layer.The results of this study indicated that the highest value of tensile stresswas found on the use E7018 electrodes and 80 amperes electric current. While the lowest value was found in the use E6013 electrodes with 120 amperes. Intermetallic layer was detected base on the SEM-EDS investigation.

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