brass ferrules have been used as packing in a laboratory- scale glass distillation column approaching pilot plant size because of their availability in all sizes and low cost. the available size range is such that these ferrules could also be used in industry and the results of this study could be scaled up. the performance of the new packing has been compared with the performance of glass pack...

in the present study, computational fluid dynamics (cfd) techniques and artificial neural networks (ann) are used to predict the pressure drop value (δp ) of al2o3-water nanofluid in flat tubes. δp  is predicted taking into account five input variables: tube flattening (h), inlet volumetric flow rate (qi  ), wall heat flux (qnw  ), nanoparticle volume fraction (φ) and nanoparticle diameter (dp ...

the harvested walnut has a relatively high moisture content of 30% compared with the safe storage moisture content of 8%. one of the common means of reducing the moisture content is by drying. for design of drying and other aeration systems for agricultural products including walnuts, the relationship between the drop in pressure and airflow velocity must be known. an airflow resistance app...

ramadan is a holy month for muslims and fasting in this month is the rule for any healthy matured person. nutritional and behavioral changes occurred during ramadan fasting may lead to several physiological change, such as blood pressure (2). studies evaluated the effects of ramadan fasting on blood pressure in hypertensive patients, are scarce and reported inadequate results. in this paper a s...

background: previous studies have indicated that ramadan fasting has beneficial effects on cardiovascular risk factors, specially blood pressure and heart rate. in the present study, the effect of ramadan fasting on 24-hour ambulatory blood pressure and heart rate has been investigated. materials and methods: this prospective observational study was conducted on two groups of individuals. six p...

abstract background and objective: obesity is an important risk factor for development of hypertension. we investigated the association between body mass index (bmi) and blood pressure in adolescents. methods: the cross-sectional study was performed on 694 adolescents aged 12-18 years from middle and high schools located in 4 districts of shiraz, iran. height, weight, and systolic and diastolic...

background: a pressure ulcer is a complication related to the need for the care and treatment of primarily disabled and elderly people. with the decrease of the blood flow caused by the pressure loaded, ulcers are formed and the tissue will be wasted with the passage of time. objective the aim of this study was to construct blood flow monitoring system on the heel tissue which was under externa...

it is accepted that noise pollution has a major impact on health, such as physical, physiological, psychological and performance related effects, all over the world. this study aims to evaluate noise pollution in four urban parks located in sanandaj city, iran and to zone it in gis environment. sound pressure level (spl) and maximum sound level (lmax) were measured at 45 points (each point was ...

background: creating a socket with proper fit is an important factor to ensure the comfort and control of prosthetic devices. several techniques are commonly used to cast transtibial stumps but their effect on stump shape deformation is not well understood. this study compares the dimensions, circumferences and volumes of the positive casts and also the socket comfort between two casting method...

this study aimed to estimate the rate of pressure ulcers in intensive care units (icus) and medical and surgical wards of iranian hospitals and compare the performance of methods of medical record review as well as direct observation for their detection.the research team visited 308 patients in medical and surgical wards of hospitals affiliated with tehran university of medical sciences and a f...