126 research outputs found
Smart water for eor by membranes
Master's thesis in Environmental technologyDesign of smart water for carbonate reservoir, using membrane process is the focus of the thesis. The desirable characteristics of smart water is low salinity or low NaCl concentrations while retaining divalent ions such as Ca2+, Mg2+, SO42- for improving the wettability. Experimental setup of the project consists of a Nanofiltration (NF) and a Reverse Osmosis (RO) membrane system for ion separation.
The retentate from NF is selected as the main constituent of the smart water due to the property of NF to retain the divalent ions. The results of the selected NF membrane show retention of 99 % of SO42-, 61 % of Mg2+, 31 % of Ca2+, 9 % of Na+ and 7 % of Cl- at a feed flow rate of 145 L/h.
A sensitivity test by spiking Na2SO4 in the feed seawater has shown interesting results of decrease in retention of Cl- with an increase of sulphate concentration. The results also show a reduction in permeate flux as the concentration of Na2SO4 increases.
The RO experiments have produced permeate with TDS level as low as 1620 ppm from the filtered seawater having a TDS level of 30200 ppm. The comparison of NF and RO experiments has confirmed the selectivity of NF to retain divalent ions at a low operating pressure for NF.
The challenge in producing the smart water requirements is the high TDS left in the retentate by NF. In order to overcome this, three options to dilute the retentate is evaluated in the thesis. The options under consideration are combinations of NF with RO, MSFD (Multi-stage flash distillation) and fresh water. The dilution ratio depends on the tolerable limit of total TDS for smart water and at the same time, retaining the divalent ions in the retentate.
Mixing of NF retentate with fresh water (0.43 kWh/m3) emerges as the optimal option in terms of minimum energy consumption for smart water production. However, due to the constraints on availability of fresh water and its socio-environmental impact, the combination process of NF and RO (3.84 kW h/m3) is proposed as the viable process for producing smart water. This option has the benefit of less environmental impact by reduced energy consumption and no chemical addition
Testing the consistency between cosmological measurements of distance and age
We present a model independent method to test the consistency between
cosmological measurements of distance and age, assuming the distance duality
relation. We use type Ia supernovae, baryon acoustic oscillations, and
observational Hubble data, to reconstruct the luminosity distance D_L(z), the
angle averaged distance D_V(z) and the Hubble rate H(z), using Gaussian
processes regression technique. We obtain estimate of the distance duality
relation in the redshift range 0.1<z<0.73 and we find no evidence for
inconsistency between the data sets used.Comment: 5 pages, 1 pdf figure, minor revision, accepted for publication in
Physics Letters
Effectiveness of paced breathing on labor pain perception among primi mothers during first stage of labor in a selected hospital, Kanyakumari District
An experimental study was conducted to evaluate the effectiveness of paced breathing on labor pain perception among primi mothers during first stage of labor in a selected hospital, Kanyakumari District.
The investigator used true experimental pre test post test Control group design with sample size 60 by Simple random sampling technique (Lottery method), and Numerical pain scale as the tool for assessing the level of labor pain perception. Paced breathing exercise taught for the Study group and the level of pain perception was assessed by Numerical pain scale after each contractions. The data gathered were analyzed by descriptive and inferential statistical methods and interpretations were made on the basis of the objectives of the study.
Majority of the demographic variables in study group, 22(73%) of them belonged to 23-26 years of age, 15(50%) of them were Hindus , 17 (57%) of them were graduates, 13(43%) of them were private employees, 21(70%) of them were earning monthly family income of Rs.6001-10000, 22(73%) of them living in rural area, 13(43%) of them belonging to extended family and the demographic variable in Control group, 15 (50%) of them belonged to 23-26 years of age, 13(43.3%) of them were Hindus, 15 (50%) of them were graduates, 13(46.6%) of them were private employees, 21(70%) of them were earning monthly family income of Rs.6001-10000, 23(77%) of them living in rural area and 10 (33.3%) were belonging to nuclear, joint and extended
family respectively.
During pre test both study group and control group, 60 (100%) had severe pain. During post test, in study group, 14 (46.6 %) had mild pain, 16(53.3 %) had moderate pain and none had severe pain. In control group, 27(90%) had severe pain, 3(10%) had moderate pain and none had mild pain. There was significant difference in the pre test and post test level of pain perception in study group and control group at 5% significant level.
In post test, mean score of level of pain perception of the study group was 3.5 and the mean score of the control group was 7.6. There was significant difference between the study group and control group computed through independent βtβ test. (t=17.88). The score represents the effectiveness of paced breathing on reduction of labor pain at 5% significant level. There was no association between the post test levels of pain perception with the selected demographic variables. Researcher concluded as per the study that the pain experienced by the mothers during labor can be reduced by performing paced breathing exercises which is cost effective and best method. This study statistically proved the effectiveness of paced breathing in reducing labor pain
Implicit Social Biases in People With Autism
Implicit social biases are ubiquitous and are known to influence social behavior. A core diagnostic criterion of autism spectrum disorders (ASD) is abnormal social behavior. We investigated the extent to which individuals with ASD might show a specific attenuation of implicit social biases, using Implicit Association Tests (IATs) involving social (gender, race) and nonsocial (nature, shoes) categories. High-functioning adults with ASD showed intact but reduced IAT effects relative to healthy control participants. We observed no selective attenuation of implicit social (vs. nonsocial) biases in our ASD population. To extend these results, we supplemented our healthy control data with data collected from a large online sample from the general population and explored correlations between autistic traits and IAT effects. We observed no systematic relationship between autistic traits and implicit social biases in our online and control samples. Taken together, these results suggest that implicit social biases, as measured by the IAT, are largely intact in ASD
Wave forecasting and monitoring during very severe cyclone Phailin in the Bay of Bengal
Wave fields, both measured and forecast during the very severe cyclone Phailin, are discussed in this communication. Waves having maximum height of 13.54 m were recorded at Gopalpur, the landfall point of the cyclone. The forecast and observed significant wave heights matched well at Gopalpur with correlation coefficient of 0.98, RMS error of 0.35 m and scatter index of 14%. Forecasts were also validated in the open ocean and found to be reliable (scatter index < 15%). The study also revealed the presence of Southern Ocean swells with a peak period of 20-22 sec hitting Gopalpur coast along with the cyclone-generated waves
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