121 research outputs found
EFFECT OF ENERGETIC ION BOMBARDMENT DURING THE GROWTH OF HYDROGENATED AMORPHOUS CARBON THIN FILMS
Hydrogenated amorphous carbon (a-C:H) thin film growth using plasma-assisted deposition is studied using Monte Carlo based simulation. The effect of energetic bombardment of the ionized depositing species as well as ionized buffer gas species on the film growth and the resulting film properties is investigated. The ion energies that assist the a-C:H film growth from low density structures to high density structures such as diamond-like carbon (DLC) are used and the effect of energy and composition of the depositing species on the C-C and C-H bonding and the film structure are analyzed. It is found that the ion bombardment favors the formation of a-C:H films with low H contents, high density and superior mechanical strength of the resulting thin films and is therefore an effective way to tailor-made a-C:H thin film growth for specific applications
Lifetimes of Fine Levels of Li Atom for 20 < n < 31 by Extended Ritz Formula
Lithium and lithium-like elements look like hydrogen atoms if their two
electrons and the nucleus are considered a core around which a single electron
is orbiting. The energy and radii expressions for hydrogen atoms can be used
for lithium and lithium-like elements; an important modification is introducing
an effective principal quantum number. The effective principal quantum number
differs from the principal quantum number of hydrogen by the quantum defect.
Quantum defect has respective values for various levels of lithium and lithium
ions. In this study, we used extended Ritz formulas to calculate quantum
defects required to calculate energies of ns, np, nd, and nf series. Using
these energies, we calculated transition probabilities and then the lifetimes
of the lithium levels. The lifetimes were calculated with the published data;
an excellent agreement was recorded. The work also extended the available list
of lifetimes. Forty lifetimes are new and presented for the first time. a
polynomial for each of the ns, np, nd, and nf series lifetimes has been
produced that fits well the lifetime valuesComment: 9 Pages 4 table
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Comparison on the effectiveness of different chemical treatments of built-up broiler litter on broiler house environment and broiler performance
The objectives in these four experiments were to observe
the effectiveness of sodium bisulfate and clinoptilolite and
different methods of application of sodium bisulfate, ferrous
sulfate heptahydrate and Micro Aide® on atmospheric ammonia
level in the broiler house and on broiler performance.
The first experiment was conducted to determine the
optimum effective level of the litter application of sodium
bisulfate. Atmospheric ammonia at 4 weeks and litter moisture
at 3 weeks
treated-pens
were significantly lower in sodium bisulfate
(488 g/m²) than in the untreated control pens.
However, broiler performance was not significantly affected
with any treatment. Litter application of sodium bisulfate at
244 g/m² and 488 g/m² were comparable and better than the 122
g/m² and untreated control.
In Experiments 2 and 3 comparisons of litter chemical
treatments of liquid Micro Aid® (8.75 ml/L H₂O) applied at 0,
2, 4,and 6 weeks; granular Micro Aid® (0.5 mg/g of feed) fed
continuously throughout the experiment, and litter application
of ferrous sulfate (732 g/m²); clinoptilolite (2443 g/m²),
sodium bisulfate (244 g/m²) and ferrous sulfate (732 g/m²) were
made for 7 week periods. Ferrous sulfate-treated pens (732
g/m²) had significantly lower litter pH at 2, 4 and 6 weeks
than untreated control and significantly lower atmospheric
ammonia levels at 3 and 6 weeks than the clinoptilolite (2443
g/m²), sodium bisulfate (244 g/m²) and untreated control in the
other experiment.
In the fourth experiment, sodium bisulfate was applied
twice (244 g/m²/application) at 0 and 4 weeks, sodium
bisulfate applied once (488 g/m²) and ferrous sulfate applied
once (732 g/m²) prior to the experiment. At 4 weeks mean body
weights and feed conversion were significantly better with one
sodium bisulfate application than the untreated control. At
7 weeks feed conversion (P<0.08) and male body weights (P<0.1)
were slightly better in one sodium bisulfate application than
in the untreated control while mortality was significantly
lower in the untreated control pens. Most mortality occurred
after 4 weeks and were due primarily to Sudden Death Syndrome.
Atmospheric ammonia levels at 0, 1, 2, 3 and 4, weeks and
litter pH levels at 0, 1, 2, 3, and 4 weeks were significantly
lower in pens with one application of sodium bisulfate than in
pens untreated. Litter application of sodium bisulfate once
(488 g/m²) seemed to be the best litter treatment in reducing
atmospheric ammonia
STRUCTURAL PROPERTIES OF NITROGEN DOPED ANATASE AND RUTILE TiO2 THIN FILMS
Anatase and rutile TiO2 thin films have been doped by N ion implantation. The effect of N doping on the structural changes of TiO2 thin films and its correlation to the optical and chemical properties of the films is investigated. The depth and concentration of the implanted N atoms is found not to exhibit substantial difference for anatase and rutile phases. The energy loss of the implanted N atoms correlates well to the energy gained by O and Ti atoms in the TiO2 lattice. An increased number of O vacancies are found to be generated as compared to Ti for both anatase and rutile phases. The energy loss mechanisms of the implanted N atoms together with the O vacancy generation are found to be the major driving forces for facilitating enhanced optical and chemical properties of the TiO2 thin films
Neural Network and Regression Methods for Estimation of the Average Daily Temperature of Hyderabad for the Years 2018-2020
A qualitative study on temperature distribution has been executed in Hyderabad by several researchers. This study, however, is the first attempt to study temperature distribution quantitatively. Two different methods, i.e., Artificial Neural Network (ANN) and Regression Analysis (RA), have been used to determine the average daily temperature distribution for Hyderabad, a city in Pakistan. Both the methods are used to predict the average daily temperature of the years; 2018, 2019, and 2020. In Neural Network (NN) analysis, the network was trained and validated for three years with temperature recorded from 2015-2017. With the help of training and validation parameters of the hidden layer, the average d aily temperature was predicted for 2018-2020. Based on input parameters (dew point, relative humidity, and wind speed), a multiple regression model was developed, and average daily temperature for the years 2018-2020 was predicted again. For validation of the model statistical errors, Root Mean Square Error (RMSE), Mean Absolute Error (MABE), Mean Absolute Percent Error (MAPE), and coefficient of determination are calculated. The statistical errors show that multiple regression models and neural network models provide a good prediction of temperature distribution. However, the results of the neural network are better than the regression model
Measuring the influence of chronic diseases on health-related major life changing decisions and development of a patient-based novel instrument for its measurement
The permanent nature of chronic disease may impair patients' psycho-social and physical well being, may change their attitude towards life goals and influence major life changing decisions (MLCDs) over time. Very little information is available in the literature about the long term impact of chronic diseases, particularly their influence on MLCDs. The aim of this study was to investigate the influence of chronic diseases on MLCDs and to develop a standardised tool for use across all chronic conditions to assess the impact of disease on MLCDs. 675 patients (100 from 6 specialties: cardiovascular, rheumatoid, diabetes, cystic fibrosis, chronic obstructive pulmonary disease, nephrology and 75 from dermatology) from the University Hospital of Wales, Cardiff and University Hospital Llandough, Llandough were invited to take part. The data was obtained through surveys, interviews and focus group discussions and this was reduced to core items through 'content analysis'. In a further study, 225 patients from the seven specialties were asked to complete the MLCDP (version la) and, factor analysis was applied to confirm the breadth and depth of the allocated domains and to determine construct validity of the MLCDP. 385 (57%) patients of 675 took part in the first phase of the study. Themes and statements generated from 316 (82%) evaluable responses (postal survey=258, individual interviews=50, focus group=8) were used for the development of the MLCD Profile. The most frequently reported MLCDs concerned early retirement, having children, job, career choice, relationships, housing, moving abroad and education. The correlation between the patients' age and the total number of reported MLCDs was significant (rs = -0.46, p=<0.001, n=308) showing negative relationship. In total, 41 affected MLCD themes were identified and grouped into 15 core MLCD categories. The working definition of health-related 'Major Life Changing Decision' was also developed. The 45-item draft profile was grouped into six MLCD domains. 19 clinicians took part in the 'content validation' stage and there was good agreement among the panel members for their ratings of language clarity, relevance, completeness and scaling. (Interclass correlation coefficient=0.71, p=<0.0001, CI=0.61-0.78, kappa coefficient=0.81, p=<0.0001, 0=0.69-0.93). This led to a new 41-item version of the MLCDP (version la), covering five MLCD domains: education, job/career, family/relationships, social and physical. 210 patients (30 from each of the seven specialties) were recruited into the second phase completed the MLCDP and data were analysed using factor analysis. The Cronbach's alpha value of 0.8 indicated good reliability. Several items were made redundant as a result of factor analysis this analysis supported the evidence of construct validity. Item prevalence ranking helped to retain conceptually important items at this stage. This profile was easy to complete for most patients (n=131, 97%) and mean completion time was 5.7 minutes. A 32-item version of the MLCDP (version 2) was finally developed, which requires future examination of its other psychometric properties. The MLCDP is potentially of benefit in alerting clinicians to the long term impact of a chronic disease on patients, and as a tool to assess the true burden of chronic diseases on individuals' long term quality of life. Clinicians' knowledge about the influence of chronic diseases on MLCDs is important to provide better and timely guidance to patients, to support better treatment decisions and eventually to lead to better health outcomes. This study also proposed strategies for patients to consider when taking MLCDs. Such support might result in more appropriate decision-taking and improved health outcomes
The Electrokinetic Stabilization (EKS) Green Approach Towards Improving the Geotechnical Properties of the Gulf Sabkha Soil at Rabigh, Saudi Arabia
Objectives: Sabkha soil is widely formed in the Arabian Gulf in the Kingdom of Saudia Arabia, particularly along the coastline. Over the past 25 years, numerous studies have been conducted to understand and characterize sabkha soil and increase its strength and durability. To enhance the geotechnical properties of Sabkha soil using an environmentally friendly electrokinetic stabilization method. From a geotechnical perspective, the construction process heavily depends on improving weak soil strength, durability, and treatment cost. The presence of water, high salinity, low shear strength, and low specific gravity are the soft geotechnical features that need to be enhanced before any construction on sabkha soil. Methods/Analysis: The electrokinetic stabilization method was applied to extract salty particles and enhance the geotechnical properties of sabkha soil. The voltage gradient of 40 V was applied for 1, 3, and 7 days using stainless steel electrodes. Findings: The result showed an outstanding improvement of sabkha soil geotechnical properties where the shear strength was increased from 116 to 165, 230, and 360 kPa for Rabigh I (RI), 122 to 155, 254, and 371 kPa for Rabigh II (RII), and for Rabigh III (RIII), the shear strength was improved up to 405 kPa. The moisture content decreased from 34.5 to 16.8% for RI, 35.2 to 15.9% for RII, and 37.5 to 14.7% for RIII. Novelty and applications: Experimental results demonstrated that all parameters were improved massively by increasing the voltage gradient and operational time. This technique is highly recommended to strengthen weak soil and improve geotechnical properties
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