Search results for: detachment diameter

Authors: K. Jagannath, Akhilesh Kotian, S. S. Sharma, Achutha Kini U., P. R. Prabhu

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Boiling process is characterized by the rapid formation of vapour bubbles at the solid–liquid interface (nucleate boiling) with pre-existing vapour or gas pockets. Computational fluid dynamics (CFD) is an important tool to study bubble dynamics. In the present study, CFD simulation has been carried out to determine the bubble detachment diameter and its terminal velocity. Volume of fluid method is used to model the bubble and the surrounding by solving single set of momentum equations and tracking the volume fraction of each of the fluids throughout the domain. In the simulation, bubble is generated by allowing water-vapour to enter a cylinder filled with liquid water through an inlet at the bottom. After the bubble is fully formed, the bubble detaches from the surface and rises up during which the bubble accelerates due to the net balance between buoyancy force and viscous drag. Finally when these forces exactly balance each other, it attains a constant terminal velocity. The bubble detachment diameter and the terminal velocity of the bubble are captured by the monitor function provided in FLUENT. The detachment diameter and the terminal velocity obtained is compared with the established results based on the shape of the bubble. A good agreement is obtained between the results obtained from simulation and the equations in comparison with the established results.

Keywords: bubble growth, computational fluid dynamics, detachment diameter, terminal velocity

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Authors: R. S. Hassani, S. Chikh, L. Tadrist, S. Radev

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A bubbly flow in a vertical miniature tube is analyzed theoretically. The liquid and gas phase are co-current flowing upward. The gas phase is injected via a nozzle whose inner diameter is 0.11mm and it is placed on the axis of the tube. A force balance is applied on the bubble at its detachment. The set of governing equations are solved by use of Mathematica software. The bubble diameter and the bubble generation frequency are determined for various inlet phase velocities represented by the inlet mass quality. The results show different behavior of bubble growth and detachment depending on the tube size.

Keywords: two phase flow, bubble growth, mini-channel, generation frequency

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Authors: Bassam M. Abunahel, Nurul Zahirah Noor Azman, Munirah Jamil

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The effect of needle diameter on the morphological structure of electrospun n-Bi₂O₃/epoxy-PVA nanofibers has been investigated using three different types of needle diameters. The results were observed and investigated using two techniques of scanning electron microscope (SEM). The first technique is backscattered SEM while the second is secondary electron SEM. The results demonstrate that there is a correlation between the needle diameter and the morphology of electrospun nanofibers. As the internal needle diameter decreases, the average nanofiber diameter decreases and the fibers get thinner and smoother without agglomeration or beads formation. Moreover, with small needle diameter the nanofibrous porosity get larger compared with large needle diameter.

Keywords: needle diameter, fiber diameter, porosity, agglomeration

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Authors: Clara Eichberger, Daantje Derks, Hannes Zacher

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Technology-assisted supplemental work (TASW) involves performing job-related tasks after regular working hours with the help of technological devices. Due to emerging information and communication technologies, such behavior becomes increasingly common. Since previous research on the relationship of TASW, psychological detachment and well-being are mixed, this study aimed to examine the moderating roles of appraisal and cognitive coping. A moderated mediation model was tested with daily diary data from 100 employees. As hypothesized, TASW was positively related to negative affect at bedtime. In addition, psychological detachment mediated this relationship. Results did not confirm appraisal and cognitive coping as moderators. However, additional analyses revealed cognitive coping as a mediator of the positive relationship of TASW and positive affect at bedtime. These results suggest that, on the one hand engaging in TASW can be harmful to employee well-being (i.e., more negative affect) and on the other hand, it can also be associated with higher well-being (i.e., more positive affect) in case it is accompanied by cognitive coping.

Keywords: cognitive coping, psychological detachment, technology-assisted supplemental work, well-being

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Authors: Andriati Nadhilah Widyarini, Ezra Margareth

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Introduction: Rhegmatogenous retinal detachment is a condition where there’s a break in the retina, which allows the vitreous to directly enter the subretinal space. Proliferative vitreoretinopathy (PVR) may develop due to this condition and can result in a new break, which could cause traction on the previously detached retina. Various methods of therapy can be done to treat this complication. Case: This case series involved 2 eyes of 2 patients who had total retinal detachment with advanced PVR. Pars plana vitrectomy was performed, and a 360-degree retinectomy procedure with perfluorocarbon liquid usage was done. This was followed by endo laser retinopexy to surround the border of retinectomy. 5000 cs silicone oil was used in 1 eye, whereas 12% of perfluoropropane gas was used in the other eye as a tamponade. These procedures were performed with meticulous attention to prevent any fluid from entering the subretinal space. Postoperative examination showed attachment of the retina and improvement of the patient’s visual acuity. Both eyes’ intraocular pressure was in the normal range. One eye developed retinal displacement, but no other complications occurred. Discussion: Rhegmatogenous retinal detachment with advanced PVR is a complex situation for vitreoretinal surgeons. PVR is characterized by the growth and migration of preretinal or subretinal membranes. PVR is the most common cause of retinal reattachment failure. A 360-degree retinectomy is an alternative surgical method to overcome this condition. Objectives of this procedure are releasing retinal traction caused by PVR, reducing the recurrence rate of PVR, and reattaching the retina to the pigment epithelial surface. Conclusion: 360-degree retinectomy provides satisfactory retinal reattachment and visual outcome improvement in rhegmatogenous retinal detachment with advanced PVR.

Keywords: RRD, retinectomy, pars plana, advanced PVR

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Authors: Hamidreza Torabi, Mohsen Moghtaderi

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Introduction: Currently, deep vitrectomy with silicone oil tamponade is the standard treatment method for patients with Rhegmatogenous Retinal Detachment (RRD). After retinal repair, it is necessary to remove silicone oil from the eye, but the appropriate time to remove the oil and complications related to that time has been less studied. The aim of this study was to compare the results of the early removal of silicone oil with the delayed removal of silicone oil in patients with RRD. Method & material: Patients who were referred to the Ophthalmology Clinic of Baqiyatallah Hospital, Tehran, Iran, due to RRD with detached macula in 2021 & 2022 were evaluated. These patients were treated with deep vitrectomy and silicone oil tamponade. Patients whose retinas were attached after the passage of time were candidates for silicone oil removal (SOR) surgery. For patients in the early SOR group, SOR surgery was performed 3-6 months after the initial vitrectomy surgery, and for the late SOR group, SOR was performed after 6 months after the initial vitrectomy surgery. Results: In this study, 60 patients with RRD were evaluated. 23 (38.3%) patients were in the early group, and 37 (61.7%) patients were in the late group. Based on our findings, it was seen that the mean visual acuity of patients based on the Snellen chart in the early group (0.48 ± 0.23 Decimal) was better than the late group (0.33 ± 0.18 Decimal) (P-value=0.009). Retinal re-detachment has happened only in one patient with early SOR. Conclusion: Early removal of silicone oil (less than 6 months) from the eyes of patients undergoing RRD surgery has been associated with better vision results compared to late removal.

Keywords: retinal detachment, vitrectomy, silicone oil, silicone oil removal, visual acuity

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Authors: W. Intagun, T. Khamdaeng, P. Prom-ngarm, N. Panyoyai

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Biochar has been used as a soil amendment since it has high porous structure and has proper nutrients and chemical properties for plants. Product yields produced from biochar kiln are dependent on process parameters and kiln types used. The objective of this research is to investigate the effect of core puncture diameter on biochar kiln efficiency, i.e., yields of biochar and produced gas. Corncobs were used as raw material to produce biochar. Briquettes from agricultural wastes were used as fuel. Each treatment was performed by changing the core puncture diameter. From the experiment, it is revealed that the yield of biochar at the core puncture diameter of 3.18 mm, 4.76 mm, and 6.35 mm was 10.62 wt. %, 24.12 wt. %, and 12.24 wt. %, of total solid yields, respectively. The yield of produced gas increased with increasing the core puncture diameter. The maximum percentage by weight of the yield of produced gas was 81.53 wt. % which was found at the core puncture diameter of 6.35 mm. The core puncture diameter was furthermore found to affect the temperature distribution inside the kiln and its thermal efficiency. In conclusion, the high efficient biochar kiln can be designed and constructed by using the proper core puncture diameter.

Keywords: anila stove, bio-char, soil conditioning materials, temperature distribution

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Authors: Yuta Kurashina, Chikahiro Imashiro, Kiyoshi Ohnuma, Kenjiro Takemura

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Research objectives and goals: To realize clinical applications of regenerative medicine, a mass cell culture is highly required. In a conventional cell culture, trypsinization was employed for cell detachment. However, trypsinization causes proliferation decrease due to injury of cell membrane. In order to detach cells using an enzyme-free method, therefore, this study proposes a novel cell detachment method capable of detaching adherent cells using acoustic radiation pressure exposed to the dish by the assistance of serum-free medium with ITS liquid medium supplement. Methods used In order to generate acoustic radiation pressure, a piezoelectric ceramic plate was glued on a glass plate to configure an ultrasonic transducer. The glass plate and a chamber wall compose a chamber in which a culture dish is placed in glycerol. Glycerol transmits acoustic radiation pressure to adhered cells on the culture dish. To excite a resonance vibration of transducer, AC signal with 29-31 kHz (swept) and 150, 300, and 450 V was input to the transducer for 5 min. As a pretreatment to reduce cell adhesivity, serum-free medium with ITS liquid medium supplement was spread to the culture dish before exposed to acoustic radiation pressure. To evaluate the proposed cell detachment method, C2C12 myoblast cells (8.0 × 104 cells) were cultured on a ø35 culture dish for 48 hr, and then the medium was replaced with the serum-free medium with ITS liquid medium supplement for 24 hr. We replaced the medium with phosphate buffered saline and incubated cells for 10 min. After that, cells were exposed to the acoustic radiation pressure for 5 min. We also collected cells by using trypsinization as control. Cells collected by the proposed method and trypsinization were respectively reseeded in ø60 culture dishes and cultured for 24 hr. Then, the number of proliferated cells was counted. Results achieved: By a phase contrast microscope imaging, shrink of lamellipodia was observed before exposed to acoustic radiation pressure, and no cells remained on the culture dish after the exposed of acoustic radiation pressure. This result suggests that serum-free medium with ITS liquid inhibits adhesivity of cells and acoustic radiation pressure detaches cells from the dish. Moreover, the number of proliferated cells 24 hr after collected by the proposed method with 150 and 300 V is the same or more than that by trypsinization, i.e., cells were proliferated 15% higher with the proposed method using acoustic radiation pressure than with the traditional cell collecting method of trypsinization. These results proved that cells were able to be collected by using the appropriate exposure of acoustic radiation pressure. Conclusions: This study proposed a cell detachment method using acoustic radiation pressure by the assistance of serum-free medium. The proposed method provides an enzyme-free cell detachment method so that it may be used in future clinical applications instead of trypsinization.

Keywords: acoustic radiation pressure, cell detachment, enzyme free, ultrasonic transducer

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Authors: Nabilah Ibrahim, Khaliza Musa

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The increment thickness of intima-media thickness (IMT) which involves the changes of diameter of the carotid artery is one of the early symptoms of the atherosclerosis lesion. The manual measurement of arterial diameter is time consuming and lack of reproducibility. Thus, this study reports the automatic approach to find the arterial diameter behavior for different gender, and body mass index (BMI) categories, focus on tracked region. BMI category is divided into underweight, normal, and overweight categories. Canny edge detection is employed to the B-mode image to extract the important information to be deal as the carotid wall boundary. The result shows the significant difference of arterial diameter between male and female groups which is 2.5% difference. In addition, the significant result of differences of arterial diameter for BMI category is the decreasing of arterial diameter proportional to the BMI.

Keywords: B-mode Ultrasound Image, carotid artery diameter, canny edge detection, body mass index

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Authors: A. Moussouni, L. Mouzai, M. Bouhadef

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Soil erosion is a very complex phenomenon, resulting from detachment and transport of soil particles by erosion agents. The kinetic energy of raindrop is the energy available for detachment and transport by splashing rain. The soil erodibility is defined as the ability of soil to resist to erosion. For this purpose, an experimental study was conducted in the laboratory using rainfall simulator to study the effect of the kinetic energy of rain (Ec) on the soil erodibility (K). The soil used was a sandy agricultural soil of 62.08% coarse sand, 19.14% fine sand, 6.39% fine silt, 5.18% coarse silt and 7.21% clay. The obtained results show that the kinetic energy of raindrops evolves as a power law with soil erodibility.

Keywords: erosion, runoff, raindrop kinetic energy, soil erodibility, rainfall intensity, raindrop fall velocity

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Authors: H. Abchiche, M. Mellal

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The aim of this work is to study the parameters that influence the rheological behavior of a complex fluid (sodium Carboxyméthylcellulose solution), on a capillary rheometer. An installation has been made to be able to vary the diameter of trial conducts. The obtained results allowed us to deduce that: the diameter of trial conducts have a remarkable effect on the rheological responds.

Keywords: bingham’s fluid, CMC, cylindrical conduit, rheological behavior

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Authors: War War Min Swe, Aung Myat Thu, Khin Cho Thet, Zaw Moe Htet, Thuzar Mon

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The main parameter of the orifice hole diameter was designed according to the range of throttle diameter ratio which gave the required discharge coefficient. The discharge coefficient is determined by difference diameter ratios. The value of discharge coefficient is 0.958 occurred at throttle diameter ratio 0.5. The throttle hole diameter is 80 mm. The flow analysis is done numerically using ANSYS 17.0, computational fluid dynamics. The flow velocity was analyzed in the upstream and downstream of the orifice meter. The downstream velocity of non-standard orifice meter is 2.5% greater than that of standard orifice meter. The differential pressure is 515.379 Pa in standard orifice.

Keywords: CFD-CFX, discharge coefficients, flow characteristics, inclined

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Authors: Sepehr Moradi

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This study investigates the contribution of individual Australian Superfine Merino Wool (ASFW) and Inner Mongolia Cashmere (IMC) fibres strength behaviour to the breaking force variation (CVBF) and minimum fibre diameter (CVₘFD) induced by actual single fibre lengths and the combination of length and diameter groups. Mid-side samples were selected for the ASFW (n = 919) and IMC (n = 691) since it is assumed to represent the average of the whole fleece. The average (LₘFD) varied for ASFW and IMC by 36.6 % and 33.3 % from shortest to longest actual single fibre length and -21.2 % and -21.7 % between longest-coarsest and shortest-finest groups, respectively. The tensile properties of single animal fibres were characterised using Single Fibre Analyser (SIFAN 4). After normalising for diversity in fibre diameter at the position of breakage, the parameters, which explain the strength behaviour within actual fibre lengths and combination of length-diameter groups, were the Intrinsic Fibre Strength (IFS) (MPa), Min IFS (MPa), Max IFS (MPa) and Breaking force (BF) (cN). The average strength of single fibres varied extensively within actual length groups and within a combination of length-diameter groups. IFS ranged for ASFW and IMC from 419 to 355 MPa (-15.2 % range) and 353 to 319 (-9.6 % range) and BF from 2.2 to 3.6 (63.6 % range) and 3.2 to 5.3 cN (65.6 % range) from shortest to longest groups, respectively. Single fibre properties showed no differences within actual length groups and within a combination of length-diameter groups, or was there a strong interaction between the strength of single fibre (P > 0.05) within remaining and removing length-diameter groups. Longer-coarser fibre fractionation had a significant effect on BF and IFS and all of the length groups showed a considerable variance in single fibre strength that is accounted for by diversity in the diameter variation along the fibre. There are many concepts for the improvement of the stress-strain properties of animal fibres as a means of raising a single fibre strength by simultaneous changes in fibre length and diameter. Fibre fractionation over a given length directly for single fibre strength or using the variation traits of fibre diameter is an important process used to increase the strength of the single fibre.

Keywords: single animal fibre fractionation, actual length groups, strength variation, length-diameter groups, diameter variation along fibre

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Authors: Ilsun Pang, Kwanghun Kim, Sungsun Baik

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Large diameter Si wafer is used as semiconductor substrate. Large diameter Si crystal ingot should be needed in order to increase wafer size. To make convection of large silicon melt stable, magnetic field is normally applied, but magnetic field is expensive and it is not proper to stabilize the large Si melt. To solve the problem, we propose a continuous Czochralski process which can be applied to small melt without magnetic field. We used granule poly, which has size distribution of 1~3 mm and is easily supplied in double crucible during silicon ingot growth. As the result, we produced 420 mm diameter ingot. In this paper, we describe an experimental study on crystal growth of large diameter silicon by Continuous Czochralski process.

Keywords: Czochralski, ingot, silicon crystal, wafer

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Authors: M. K. Yusuf, W. O. Hamman, U. E. Umana, S. B. Oladele

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Background: Dilatation of the inferior vena cava (IVC) is used as the ultrasonic diagnostic feature in patients suspected of congestive heart failure. The IVC diameter has been reported to vary among the various body mass indexes (BMI) and body shape indexes (ABSI). Knowledge of these variations is useful in precision diagnoses of CHF by imaging scientists. Aim: The study aimed to establish an equation for predicting the ultrasonic mean diameter of the IVC among the various BMI/ABSI of inhabitants of Azare, Bauchi State-Nigeria. Methodology: Two hundred physically healthy adult subjects of both sexes were classified into under, normal, over, and obese weights using their BMIs after selection using a structured questionnaire following their informed consent for an abdominal ultrasound scan. The probe was placed on the midline of the body, halfway between the xiphoid process and the umbilicus, with the marker on the probe directed towards the patient's head to obtain a longitudinal view of the IVC. The maximum IVC diameter was measured from the subcostal view using the electronic caliper of the scan machine. The mean value of each group was obtained, and the results were analysed. Results: A novel equation {(IVC Diameter = 1.04 +0.01(X) where X= BMI} has been generated for determining the IVC diameter among the populace. Conclusion: An equation for predicting the IVC diameter from individual BMI values in apparently healthy subjects has been established.

Keywords: equation, ultrasonic, IVC diameter, body adiposities

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Authors: Kshanaprava Dhalsamant, Punyadarshini P. Tripathy, Shanker L. Shrivastava

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Potato is chosen as the food product for carrying out the natural convection mixed-mode solar drying experiments since they are easily available and globally consumed. The convective heat and mass transfer coefficients along with effective diffusivity were calculated considering both shrinkage and without shrinkage for the potato cylinders of different geometry (8, 10 and 13 mm diameters and a constant length of 50 mm). The convective heat transfer coefficient (hc) without considering shrinkage effect were 24.28, 18.69, 15.89 W/m2˚C and hc considering shrinkage effect were 37.81, 29.21, 25.72 W/m2˚C for 8, 10 and 13 mm diameter samples respectively. Similarly, the effective diffusivity (Deff) without considering shrinkage effect were 3.20×10-9, 4.82×10-9, 2.48×10-8 m2/s and Deff considering shrinkage effect were 1.68×10-9, 2.56×10-9, 1.34×10-8 m2/s for 8, 10 and 13 mm diameter samples respectively and the mass transfer coefficient (hm) without considering the shrinkage effect were 5.16×10-7, 2.93×10-7, 2.59×10-7 m/s and hm considering shrinkage effect were 3.71×10-7, 2.04×10-7, 1.80×10-7 m/s for 8, 10 and 13 mm diameter samples respectively. Increased values of hc were obtained by considering shrinkage effect in all diameter samples because shrinkage results in decreasing diameter with time achieving in enhanced rate of water loss. The average values of Deff determined without considering the shrinkage effect were found to be almost double that with shrinkage effect. The reduction in hm values is due to the fact that with increasing sample diameter, the exposed surface area per unit mass decreases, resulting in a slower moisture removal. It is worth noting that considering shrinkage effect led to overestimation of hc values in the range of 55.72-61.86% and neglecting the shrinkage effect in the mass transfer analysis, the values of Deff and hm are overestimated in the range of 85.02-90.27% and 39.11-45.11%, respectively, for the range of sample diameter investigated in the present study.

Keywords: shrinkage, convective heat transfer coefficient, effectivive diffusivity, convective mass transfer coefficient

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Authors: Avantika Verma

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In industrialized nations, corneal lacerations are one of the most common reason for hospitalization. This study was designed to study visual and clinical outcome in patients presenting with full thickness corneal lacerations in Indian population and to ascertain the impact of various preoperative and operative factors influencing prognosis after repair of corneal lacerations. Males in third decade with injuries at work with metallic objects were common. Lens damage, hyphema, vitreous hemorrhage, retinal detachment and endophthalmitis were seen. All the patients underwent primary repair within first 24 hours of presentation. At 3 months, 74.3% had a good visual outcome. About 5.7% of patients had no perception of light.In conclusion, various demographic and preoperative factors like age, time of presentation, vision at presentation, length of corneal wound, involvement of visual axis, associated ocular features like hyphaema, lenticular changes, vitreous haemorrhage and retinal detachment are significant prognostic indicators for final visual outcome.

Keywords: corneal laceration, corneal wound repair, injury, visual outcome

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Authors: Karla Kristine Bay, Jovie Ann Gabin, Allana Joyce Sasotona

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This research employed an Interpretative Phenomenological Analysis to explore the experiences of Children in Conflict with the Law (CICL) which gave light to their concept of ‘friends’. Derived from this context are the following objectives of the study: 1) determining the differentiation of the forms of friends of the CICL; 2) presenting the process of attachment towards detachment in the formation of friendship; and 3) discussing the experiences, and reflections of the CICL on the ‘self’ out of their encounter with friendship. Using the data gathered from the individual drawings of the CICL of their representations of the self, family, friends, community, and Bahay Kalinga as subjects in the meaning-making process utilizing Filipino Psychology methods of pagtatanong-tanong (interview), and pakikipagkwentuhan (conversation), data analysis produced a synthesis of seventeen individual cases. Overall results generated three superordinate themes on the differentiation of the forms of friends which include friends with good influences, friends with bad influences, and friends within the family. While two superordinate themes were produced on the process of attachment towards detachment, namely social, emotional, and psychological experiences on the process of attachment, and emotional and psychological experiences on the process of detachment. Lastly, two superordinate themes were created on the experiences, and reflections of the CICL on the ‘self’ out of their encounter with friendship. This consists of the recognition of the ‘self’ as a responsible agent in developing healthy relationships between the self and others, and reconstruction of the self from the collective experiences of healing, forgiveness, and acceptance. These findings, together with supporting theories discussed the impact of friendship on the emergence of criminal behavior and other dispositions; springing from the child’s dissociation from the family that led to finding belongingness from an external group called friends.

Keywords: children in conflict with the law, criminal behavior, friends, interpretative phenomenological analysis

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Authors: Ibrahim Rassoul, E-K. Si Ahmed

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The growth, deformation, and detachment of fluid droplets adherent to solid substrates is a problem of fundamental interest with numerous practical applications. Specific interest in this proposal is the problem of a droplet on a fibrous, hydrophobic substrate subjected to body or external forces (gravity, convection). The past decade has seen tremendous advances in proton exchange membrane fuel cell (PEMFC) technology. However, there remain many challenges to bring commercially viable stationary PEMFC products to the market. PEMFCs are increasingly emerging as a viable alternative clean power source for automobile and stationary applications. Before PEMFCs can be employed to power automobiles and homes, several key technical challenges must be properly addressed. One technical challenge is elucidating the mechanisms underlying water transport in and removal from PEMFCs. On the one hand, sufficient water is needed in the polymer electrolyte membrane or PEM to maintain sufficiently high proton conductivity. On the other hand, too much liquid water present in the cathode can cause 'flooding' (that is, pore space is filled with excessive liquid water) and hinder the transport of the oxygen reactant from the gas flow channel (GFC) to the three-phase reaction sites. The aim of this work is to investigate the stability of a liquid water droplet emerging form a GDL pore, to gain fundamental insight into the instability process leading to detachment. The approach will combine analytical and numerical modeling with experimental visualization and measurements.

Keywords: polymer electrolyte fuel cell, water droplet, gas diffusion layer, contact angle, surface tension

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Authors: H. A. Mansour

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The objective of this research work is studying the water use prediction, prediction technology for water use by action agencies, and others involved in conservation, planning, and environmental assessment of the Water Erosion Prediction Project (WEPP) simulation model. Models the important physical, processes governing erosion in Egypt (climate, infiltration, runoff, ET, detachment by raindrops, detachment by flowing water, deposition, etc.). Simulation of the non-uniform slope, soils, cropping/management., and Egyptian databases for climate, soils, and crops. The study included important parameters in Egyptian conditions as follows: Water Balance & Percolation, Soil Component (Tillage impacts), Plant Growth & Residue Decomposition, Overland Flow Hydraulics. It could be concluded that we can adapt the WEPP simulation model to determining the previous important parameters under Egyptian conditions.

Keywords: WEPP, adaptation, soil properties, tillage impacts, water balance, soil percolation

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Authors: Farnoush Haghanipour

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Recent research studies relation between coping strategies with stress and mental health situation in flying addicted family of self-introducer and private, Units of Guilan province. For this purpose 251 family (parent, spouse), that referred to private and self-introducer centers to break out of drug are selected in random sampling form. Research method was cross sectional-descriptive and purpose of research was fixing of between kinds of coping strategies with stress and mental health condition with attention to demographic variables. Therefore to collection of information, coping strategies questionnaire (CSQ) and mental health questionnaire (GHQ) was used and finally data analyzed by descriptive statistical methods (average, standard deviation) and inferential statistical correlation coefficient and regression. Study of correlation coefficient between mental healths with problem focused emotional focused and detachment strategies in level more than %99 is confirmed. Also mental health with avoidant focused hasn't correlation in other words relation is between mental health with problem focused strategies (r= 0/34) and emotional focused with mental health (r=0.52) and detachment with mental health (r= 0.18) in meaningful level 0.05. And also relation is between emotional focused strategies and mental health (r= 0.034) that is meaningless in Alpha 0.05. Also relation between problem processed coping strategies and mental health situation with attention to demographic variable is meaningful and relation level verified in confidence level more than 0.99. And result of anticipation equation regression statistical test has most a have in problem focused coping strategy, mental health, but relation of the avoidant emotional, detachment strategy with mental health was meaningless with attention to demographic variables.

Keywords: stress, coping strategy with stress, mental health, self introducer and private

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Authors: Nidhi S. Bisht

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The study examines the role of work-home interference, on enhancing emotional exhaustion in the branch officers of private MFIs in India. Additionally, the moderating role of recovery experiences and technology-assisted supplemental work (TASW) were studied. With the increasing expectations to perform job related tasks at home, technology-assisted supplemental work (TASW) was hypothesized to positively moderate the relationship between work-home interference and emotional exhaustion. Further, it was expected that recovery experiences-psychological detachment, relaxation will help to recover and unwind from work and negatively moderate the relationship between work-home interference and emotional exhaustion. Results of SEM-analyses largely offered support for the hypotheses. These findings increase our insight in the processes leading to increased emotional exhaustion and suggest that employees can protect themselves from emotional exhaustion by keeping a tab on technology-assisted supplemental work and facilitating recovery experiences.

Keywords: emotional exhaustion, India, microfinance institutions (MFIs), work-home interference

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Authors: C. Agrawal, R. Kumar, A. Gupta, B. Chatterjee

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An experimental investigation has been carried out to study the cooling of a hot horizontal Stainless Steel surface of 3 mm thickness, which has 800±10 °C initial temperature. A round water jet of 22 ± 1 °C temperature was injected over the hot surface through straight tube type nozzles of 2.5-4.8 mm diameter and 250 mm length. The experiments were performed for the jet exit to target surface spacing of 4 times of jet diameter and jet Reynolds number of 5000-24000. The effect of change in jet Reynolds number on the surface quenching has been investigated form the stagnation point to 16 mm spatial location.

Keywords: hot-surface, jet impingement, quenching, stagnation point

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Authors: Ashraf Mohammed M. Eid, Hossam El Badry

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The bored pile friction resistance may be affected by many factors such as the method of construction, pile length and diameter, the soil properties, as well as the depth below ground level. These factors can be represented analytically to study the influence of diameter on the unit skin friction. In this research, the Egyptian Code of soil mechanics is used to assess the skin friction capacity for either the ordinary pile diameter as well as for the large pile diameter. The later is presented in the code and through the work of some researchers based on the results of investigations adopted for a sufficient number of field tests. The comparative results of these researchers with respect to the Egyptian Code are used to check the adequacy of both methods. Based on the results of this study, the traditional static formula adopted for piles of diameter less than 60 cm may be continually used for larger piles by correlating the analyzed formulae. Accordingly, the corresponding modified angle of internal friction is concluded demonstrating a reduction of shear strength due to soil disturbance along the pile shaft. Based on this research the difference between driven piles and bored piles constructed in same soil can be assessed and a better understanding can be evaluated for the effect of different factors on pile skin friction capacity.

Keywords: large piles, static formula, friction piles, sandy soils

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Authors: C. Milind Caspar, Valtonia Octavio Massingue, K. Maneesh Reddy, K. V. Ramesh

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Gas holdup data were obtained from measured pressure drop values in a gas-liquid upflow bubble column in the presence of string of hemispheres promoter internal. The parameters that influenced the gas holdup are gas velocity, liquid velocity, promoter rod diameter, pitch and base diameter of hemisphere. Tap water was used as liquid phase and nitrogen as gas phase. About 26 percent in gas holdup was obtained due to the insertion of promoter in in the present study in comparison with empty conduit. Pitch and rod diameter have not shown any influence on gas holdup whereas gas holdup was strongly influenced by gas velocity, liquid velocity and hemisphere base diameter. Correlation equation was obtained for the prediction of gas holdup by least squares regression analysis.

Keywords: bubble column, gas-holdup, two-phase flow, turbulent promoter

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Authors: Manwendra Kumar Tripathi, Subhas Ganguly

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A few glass forming ability expressions in terms of characteristic temperatures have been proposed in the literature. Attempts have been made to correlate the expression with the critical diameter of the bulk metallic glass composition. However, with the advent of new alloys, many exceptions have been noted and reported. In the present approach, a genetic programming based code which generates an expression in terms of input variables, i.e., three characteristic temperatures viz. glass transition temperature (Tg), onset crystallization temperature (Tx) and offset temperature of melting (Tl) with maximum correlation with a critical diameter (Dmax). The expression evolved shows improved correlation with the critical diameter. In addition, the expression can be explained on the basis of time-temperature transformation curve.

Keywords: glass forming ability, genetic programming, bulk metallic glass, critical diameter

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Authors: Sebastian Gerber, Julian Fesel, Christian Zimmer, Pauline Yzombard, Daniel Comparat, Michael Doser

Abstract:

Molecular anions play a central role in a wide range of fields: from atmospheric and interstellar science, anionic superhalogens to the chemistry of highly correlated systems. However, up to now the synthesis of negative ions in a controlled manner at ultracold temperatures, relevant for the processes in which they are involved, is currently limited to a few Kelvin by supersonic beam expansion followed by resistive, buffer gas or electron cooling in cryogenic environments. We present a realistic scheme for laser cooling of C2- molecules to sub-Kelvin temperatures, which has so far only been achieved for a few neutral diatomic molecules. The generation of a pulsed source of C2- and subsequent laser cooling techniques of C2- molecules confined in a Penning trap are reviewed. Further, laser cooling of one anionic species would allow to sympathetically cool other molecular anions, electrons and antiprotons that are confined in the same trapping potential. In this presentation the status of the experiment and the feasibility of C2- sympathetic Doppler laser cooling, photo-detachment cooling and AC-Stark Sisyphus cooling will be reviewed.

Keywords: antiprotons, anions, cooling of ions and molecules, Doppler cooling, photo-detachment, penning trap, Sisyphus cooling, sympathetic cooling

Procedia PDF Downloads 348

Authors: Lise P. Labéjof, Ivna Mororó, Raquel G. Bastos, Maria Isabel G. Severo, Arno H. de Oliveira

Abstract:

This work presents an alternative mode of intestine mucosa renewal that may allow to better understand the total loss of villi after irradiation. It was tested a morphological method of 3d reconstruction using micrographs of serial sections of rat duodenum. We used hundreds of sections of each specimen of duodenum placed on glass slides and examined under a light microscope. Those containing the detachment, approximately a dozen, were chosen for observation under a transmission electron microscope (TEM). Each of these sections was glued on a block of epon resin and recut into a hundred of 60 nm-thick sections. Ribbons of these ultrathin sections were distributed on a series of copper grids in the same order of appearance than during the process of microstomia. They were then stained by solutions of uranyl and lead salts and observed under a TEM. The sections were pictured and the electron micrographs showing signs of cells detachment were transferred into two softwares, ImageJ to align the cellular structures and Reconstruct to realize the 3d reconstruction. It has been detected epithelial cells that exhibited all signs of programmed cell death and localized at the villus-crypt junction. Their nucleus was irregular in shape with a condensed chromatin in clumps. Their cytoplasm was darker than that of neighboring cells, containing many swollen mitochondria. In some places of the sections, we could see intercellular spaces enlarged by the presence of shrunk cells which displayed a plasma membrane with an irregular shape in thermowell as if the cell interdigitations would distant from each other. The three-dimensional reconstruction of the crypts has allowed observe gradual loss of intercellular contacts of crypt cells in the longitudinal plan of the duodenal mucosa. In the transverse direction, there was a gradual increase of the intercellular space as if these cells moved away from one another. This observation allows assume that the gradual remoteness of the cells at the villus-crypt junction is the beginning of the mucosa detachment. Thus, the shrinking of cells due to apoptosis is the way that they detach from the mucosa and progressively the villi also. These results are in agreement with our initial hypothesis and thus have demonstrated that the villi become detached from the mucosa at the villus-crypt junction by the programmed cell death process. This type of loss of entire villus helps explain the rapid denudation of the intestinal mucosa in case of irradiation.

Keywords: 3dr, transmission electron microscopy, ionizing radiations, rat small intestine, apoptosis

Procedia PDF Downloads 356

Authors: J. Kloypayan, W. Pimpakan

Abstract:

The pipe taper thread measurement and uncertainty normally used the four-wire probe according to the JIS B 0262. Besides, according to the EA-10/10 standard, the pipe thread could be measured using the three-wire probe. This research proposed to use the three-wire probe measuring the pitch diameter of the pipe taper thread. The measuring accessory component was designed and made, then, assembled to one side of the ULM 828 CiM machine. Therefore, this machine could be used to measure and calibrate both the pipe thread and the pipe taper thread. The equations and the expanded uncertainty for pitch diameter measurement were formulated. After the experiment, the results showed that the pipe taper thread had the pitch diameter equal to 19.165 mm and the expanded uncertainty equal to 1.88µm. Then, the experiment results were compared to the results from the National Institute of Metrology Thailand. The equivalence ratio from the comparison showed that both results were related. Thus, the proposed method of using the three-wire probe measured the pitch diameter of the pipe taper thread was acceptable.

Keywords: pipe taper thread, three-wire probe, measure and calibration, the universal length measuring machine

Procedia PDF Downloads 378

Authors: C. F. Alegretti, F. R. Cunha, R. G. Gontijo

Abstract:

This work investigates the effects of an applied magnetic field on the geometry-driven boundary layer detachment flow of a ferrofluid over a sudden expansion. Both constitutive equation and global magnetization equation for a ferrofluid are considered. Therefore, the proposed formulation consists in a coupled magnetic-hydrodynamic problem. Computational simulations are carried out in order to explore, not only the viability to control flow instabilities, but also to evaluate the consistency of theoretical aspects. The unidirectional sudden expansion in a ferrofluid flow is investigated numerically under the perspective of Ferrohydrodynamics in a two-dimensional domain using a Finite Differences Method. The boundary layer detachment induced by the sudden expansion results in a recirculating zone, which has been extensively studied in non-magnetic hydrodynamic problems for a wide range of Reynolds numbers. Similar investigations can be found in literature regarding the sudden expansion under the magnetohydrodynamics framework, but none considering a colloidal suspension of magnetic particles out of the superparamagnetic regime. The vorticity-stream function formulation is implemented and results in a clear coupling between the flow vorticity and its magnetization field. Our simulations indicate a systematic decay on the length of the recirculation zone as increasing physical parameters of the flow, such as the intensity of the applied field and the volume fraction of particles. The results all are discussed from a physical point of view in terms of the dynamical non-dimensional parameters. We argue that the decrease/reduction in the recirculation region of the flow is a direct consequence of the magnetic torque balancing the action of the torque produced by viscous and inertial forces of the flow. For the limit of small Reynolds and magnetic Reynolds parameters, the diffusion of vorticity balances the diffusion of the magnetic torque on the flow. These mechanics control the growth of the recirculation region.

Keywords: boundary layer detachment, ferrofluid, ferrohydrodynamics, magnetization, sudden expansion

Procedia PDF Downloads 183