scholarly journals Depth distributions of low energy deuterium implantations in (110) tungsten: a theoretical model

1978 ◽  
Author(s):  
D.K. Brice
Keyword(s):  
Theoretical Model ◽  
Low Energy ◽  
Depth Distributions

THE COLLIDING PARTICLES MASS RATIO INFLUENCE ON PECULIARITIES OF LOW-ENERGY ION NEAR-SURFACE IMPLANTATION AT CHANNELING CONDITIONS

2018 ◽  
Vol 20 (4) ◽  
pp. 265-274
Author(s):  
F.F. Umarov ◽  
A.M. Rasulov ◽  
A.A. Dzhurakhalov
Keyword(s):  
Energy Loss ◽  
Normal Incidence ◽  
Binary Collision ◽  
Low Energy ◽  
Main Peak ◽  
Mass Ratio ◽  
Near Surface ◽  
Collision Approximation ◽  
Thin Crystal ◽  
Depth Distributions

In the present work the peculiarities of ion implantation and colliding particles mass ratio influence on the ranges, energy loss and profiles of distribution for 1−5 keV P+ ions channelling in Si(110) and SiC(110) at normal incidence, and 1 keV Be+ and Se+ ions in GaAs(100), as well as 5 keV Ar+ and Kr+ on Cu(001) surface at glancing incidence are carried out by computer simulation in binary collision approximation. It is shown that for paraxial part of a beam the main contribution to the total energy loss comes from inelastic ones. It has been established that the energy loss of ions transmitted through thin crystal and depth profile distributions depend on width of the channel and mass ratio of colliding atoms. It was shown that at grazing surface channeling conditions the main peak of the implanted depth distributions is considerably shallow, the range for Se+ ions is shallower and the half-width of profile for these ions is narrow than that for Be+ ions. The results allow one to select the optimum for implanted depth distributions with demanded shape at narrow near-surface area of crystals obtaining.

DEPTH DISTRIBUTIONS OF LOW ENERGY DEUTERIUM IMPLANTED INTO SILICON AS DETERMINED BY SIMS

1980 ◽  
pp. 383-387
Author(s):  
CHARLES W. MAGEE ◽  
SAMUEL A. COHEN ◽  
DONALD E. VOSS ◽  
DAVID K. BRICE
Keyword(s):  
Low Energy ◽  
Depth Distributions

The Mental Simulation of Motor Incapacity in Depression

2008 ◽  
Vol 22 (3) ◽  
pp. 228-249 ◽  
Author(s):  
Lisa M. Lindeman ◽  
Lyn Y. Abramson
Keyword(s):  
Theoretical Model ◽  
Mental Simulation ◽  
Low Energy ◽  
Positive Outcomes ◽  
Physiological Changes ◽  
Negative Outcomes ◽  
Causal Mechanisms ◽  
Motor Movement ◽  
Negative Beliefs ◽  
Physical Weakness

In depression, negative beliefs are coupled with profound physical weakness. Specifically, the belief that one is incapable of altering events in order to prevent expected negative outcomes or bring about positive outcomes leads to bodily symptoms characterized by low energy, slow motor movement, and delays in the initiation of movement. The purpose of this article is to present a theoretical model describing the causal mechanisms that link these cognitive and somatic elements of depression. We propose that (a) the inability to alter events is conceptualized metaphorically as motor incapacity; (b) as part of this conceptualization, the experience of motor incapacity is mentally simulated; and (c) this simulation leads to both subjective feelings of lethargy and peripheral physiological changes consistent with motor incapacity.

Layer-by-Layer Sputtering and Ultrathin Ion Implantation by Low-Energy Grazing Ion Bombardment

2005 ◽  
Vol 908 ◽  
Author(s):  
Abdurauf Dzhurakhalov ◽  
Sirojiddin Rahmatov ◽  
Nigorakhon Teshabaeva ◽  
Maqsud Yusupov
Keyword(s):  
Ion Implantation ◽  
Crystal Orientation ◽  
Ion Bombardment ◽  
Grazing Incidence ◽  
Low Energy ◽  
Layer By Layer ◽  
Ion Sputtering ◽  
Depth Distributions

AbstractThe ion sputtering and implantation into GaAs(001) surface at 1-5 keV Se+ grazing ion bombardment have been investigated by computer simulation.The azimuth angular dependencies of sputtering and penetration yield at grazing incidence have been calculated. It was observed that these dependencies correlate the crystal orientation. The depth distributions of 1-5 keV Se ions implanted into GaAs(001) for several azimuth angles of incidence have been presented.

scholarly journals Unbalanced exchange flow and its implications for the night cooling of buildings by displacement ventilation

2021 ◽  
Author(s):  
Nick Wise ◽  
Gary Hunt
Keyword(s):  
Theoretical Model ◽  
Low Energy ◽  
Exchange Flow ◽  
Displacement Ventilation ◽  
Excess Heat ◽  
Low Level ◽  
Cooling Strategy ◽  
Rate Of Cooling ◽  
Flow Changes ◽  
High Level

AbstractPassive ventilation of buildings at night forms an essential part of a low-energy cooling strategy, enabling excess heat that has accumulated during the day to self-purge and be replaced with cooler night air. Instrumental to the success of a purge are the locations and areas of ventilation openings, and openings positioned at low and at high levels are a common choice as there is then the expectation that a buoyancy-driven displacement flow will establish and persist. Desirable for their efficiency, displacement flows guide excess heat out through high-level openings and cooler air in through low-level openings. Herein we show that displacement flow cannot be maintained for the full duration of a purge. Instead, the flow must transition to an ‘unbalanced exchange flow’, whereby the cool inflow of air at low level is maintained but there is now a warm outflow and a cool inflow occurring simultaneously at the high-level opening. The internal redistribution of heat caused by this exchange alters the rate at which heat is self-purged and the time thought necessary to complete a purge. We develop a theoretical model that captures and predicts these behaviours. Our approach is distinct from all others which assume that a displacement flow will persist throughout the purge. Based on this enhanced understanding, and specifically that the transition to unbalanced exchange flow changes the rate of cooling and resultant emptying times, we anticipate that practitioners will be better placed to design passive systems that meet their target specifications for cooling.

Sign in / Sign up

Export Citation Format

Share Document