نتایج جستجو برای: protective device

تعداد نتایج: 788881  

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه صنعتی اصفهان - دانشکده مهندسی مواد 1386

در چند دهه اخیر توسعه مواد جاذب برای استتار تجهیزات نظامی از دید رادار پیشرفت شایان توجهی داشته است. آلاییدن فریت های هگزاگونالی با یون های مغناطیسی و غیر مغناطیسی، یکی از روش های افزایش میزان تلفات انعکاس این مواد در محدوده امواج رادار می-باشد. در این پژوهش، سه نوع فریت استرانسیوم آلاییده شده توسط یون های منگنز، تیتانیم و کبالت با فرمول شیمیایی srfe9mn1.5ti1.5o19، srfe9mn1.5co1.5o19 و srfe9co1...

ژورنال: طلوع بهداشت یزد 2013
عطاری, قوام الدین, علی آبادی, محسن, فرهادیان, مریم, محجوب, حسین ,

  Background: The occupational exposure conditions such as dust concentration, exposure time, smoking status and use of respiratory protection device are effective on pulmonary function disorder. The aim of this study was to determine the risk of pulmonary function disorder in the workers exposed to silica dust in the stone crushing by using Cox regression model.   Method: 117 of workers employ...

Journal: :iranian red crescent medical journal 0
ghassem mohammadkhani department of audiology, school of rehabilitation, tehran university of medical sciences, tehran, ir iran akram pourbakht department of audiology, rehabilitation research center, school of rehabilitation sciences, iran university of medical sciences, tehran, ir iran; department of audiology, rehabilitation research center, school of rehabilitation sciences, iran university of medical sciences, tehran, ir iran. tel: +98-2122250541, fax: +98-2122220946 mahnaz khanavi department of pharmacognosy and traditional, iranian medicine research center, school of pharmacy, tehran university of medical sciences, tehran, ir iran soghrat faghihzadeh department of biostatistics and social medicine, zanjan university of medical sciences, zanjan, ir iran

background hearing capability plays a principal role on human's communication. noise-induced hearing loss (nihl) caused by exposure to high noise levels is a serious socio-economic problem in modern societies. nihl can either be reversible, resulting in a temporary threshold shifts (tts) or irreversible, resulting in a permanent threshold shifts (pts). pts is often confirmed in the time span of...

Journal: :Annals of African medicine 2011
Iyiade A Ajayi Adenike O Adeoye Charles O Bekibele Oluwatoyin H Onakpoya O J Omotoye

OBJECTIVE To determine the level of awareness and practice of use of protective eye devices among welders in Ile-Ife. METHODS This is a cross-sectional descriptive study of 405 consenting welders. A pretested proforma was utilized to obtain information on sociodemographic characteristics, as well as awareness and use of protective eye device. RESULTS The age of the respondents ranged from 1...

Disconnecting microgrid from main grid, may lead to severe frequency changes. Under frequency load shedding method provides a proper protection scheme by shedding certain amount of loads. Under frequency load shedding relay is used for frequency control of islanded microgrid. Each synchronous distributed generator (DG) of microgrid is equipped with a protective islanding detection device such a...

Journal: :Biomicrofluidics 2014
Chung Yu Chan Vasiliy N Goral Michael E DeRosa Tony Jun Huang Po Ki Yuen

In this article, we present a simple, rapid prototyped polystyrene-based microfluidic device with three-dimensional (3D) interconnected microporous walls for long term perfusion cell culture. Patterned 3D interconnected microporous structures were created by a chemical treatment together with a protective mask and the native hydrophobic nature of the microporous structures were selectively made...

Journal: :DEStech Transactions on Computer Science and Engineering 2018

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید