نتایج جستجو برای: Ultraviolet irraciation

تعداد نتایج: 40519  

B. Mojazi Amiri M. Pourkazemi M.R. Kalbasi, S. Dorafshan,

Abstract:  The optimum dose of UV irradiation to produce gynogenesis rainbow trout, Oncorhynchus mykiss with emphasis of Hertwing effect and photoreactivation (PR) was investigated. For this purpose, the sperm of rainbow trout were inadiated with UV at 2010±200 µw.cm-2 intensity in different alternatives of 0, 1, 3, 5, 8, 10, 15, 20, 25, 35 and 45 minutes and allowed to fertilize normal ova; th...

Journal: :novelty in biomedicine 0
mohammadreza nazari department of optometry, faculty of rehabilitation sciences, shahid beheshti university of medical sciences, tehran, iran saeed rahmani department of optometry, faculty of rehabilitation sciences, shahid beheshti university of medical sciences, tehran, iran bahram khosravi department of optometry, faculty of rehabilitation sciences, shahid beheshti university of medical sciences, tehran, iran seyyed mehdi tabatabaei

background: wearing spectacles is the most common approach in correcting the refractive errors worldwide. due to harmful effects of overexposure to solar ultraviolet radiations, the usage of multi-layer coatings in ophthalmic lenses has recently been increased. these lenses can reduce the reflections and hence increase the transmission of visible light; they can also decrease the transmission o...

Journal: :international journal of nanoscience and nanotechnology 2014
s. rahmani m. mahmoudifard m. safi

ultraviolet waves, because of their short wavelength, have a high energy and considerable damaging effects on surfaces. protection against ultraviolet radiations is one of the finishing treatments done on surfaces exposed to sunlight. the importance of this issue in relation to human health, due to complications such as skin burns and cancer, is doubled. up to now, different materials such as z...

Journal: :iranian journal of public health 0
f.vaezi a. mesdaghinia k. imandel i b. golestan

chemical methods ( actinometry ) depend on the measurement of the extent to which a chemical reaction occurs under the influence of uv light. two chemical actinometers have been used in this research. in one method, the mixtures of potassium peroxidisuiphate butanol solutions were irradiated for various time intervals, and ph-changes were determined. a linear relationship was observed between t...

Journal: :علوم گیاهان زراعی ایران 0
حمیدرضا بلوچی سید علی محمد مدرس ثانوی یحیی امام

drought, ultraviolet radiation and atmospheric co2 are some three environmental factors that seriously affect future food security. the objective followed in the present research was to study the effect of two levels of carbon dioxide (400 and 900 ppm), ultraviolet radiation (uv a, b and c with intensities of 18, 25 and 40 microw.cm-2 respectively) and water deficit (%100 and %60 of field capac...

Journal: :تحقیقات نظام سلامت 0
شهرام صفری دانشجوی کارشناسی ارشد، گروه مهندسی بهداشت حرفه ای، دانشکده بهداشت، دانشگاه علوم پزشکی اصفهان، اصفهان، ایران مقداد کاظمی دانشجوی کارشناسی ارشد، گروه مهندسی بهداشت حرفه ای، دانشکده بهداشت، دانشگاه علوم پزشکی اصفهان، اصفهان، ایران حبیب الله دهقان استادیار، گروه مهندسی بهداشت حرفه ای، دانشکده بهداشت، دانشگاه علوم پزشکی اصفهان، اصفهان، ایران حسینعلی یوسفی مربی، گروه مهندسی بهداشت حرفه ای، دانشکده بهداشت، دانشگاه علوم پزشکی اصفهان، اصفهان،ایران بهزاد مهکی استادیار، گروه آمار و اپیدمیولوژی، دانشکده بهداشت، دانشگاه علوم پزشکی اصفهان، اصفهان، ایران

background : one way to optimize energy consumption is replacing incandescent lamp with compact fluorescent lamps .these lamps produce ultraviolet radiation due to the nature of light production. this study aimed to evaluate the ultraviolet radiation emitted from compact fluorescent lamps which are widely used in iran. methods : this study carries out on 16 compact fluorescent lamps (four diffe...

ژورنال: پژوهش در پزشکی 2011
رحمنی, سعید, طباطبایی, سید مهدی, قاسمی برومند, محمد, نظری, محمدرضا ,

Abstract Background: Solar light has various electromagnetic radiations include Ultraviolet, Visible & infrared rays. Overexposure to solar ultraviolet radiations can lead to some dangerous disorders and usage of non standard sunglasses can increase foregoing harmful effects. In Iran cataract is the most common disorder produced by UV rays. This study aims to measure the transmission of ultr...

ژورنال: سلامت و محیط زیست 2021

Background and Objective: Monitoring the amount of ultraviolet radiation from sunlight can provide a basis for assessing people's exposure, raise public awareness and warn people against this radiation. Measuring the sun's ultraviolet index over a working period is an accurate choice to achieve this goal. Materials and Methods: In this study, the amount of solar UV index in one of the outdoor ...

The present study was focused to examine the combined effects of climate and ultraviolet-B radiation on conifer tree-ring density. Statistical methods were employed to extract tree responses in annual ring density and to identify functional relationship in trees when the level of ultraviolet-B radiation changes regardless of climate variations. In this study, the consideration was given to the ...

Journal: :بهداشت و توسعه 0
روح الله مقصودی مقدم فرهاد فراستی علی طولابی زهره جعفرزاده

background: light is an important and adjustable physical factor in the job environment.this study aimed to determine the intensity of natural and mixed light and also the level of ultraviolet radiation in libraries and computer sites of ilam universities in spring 2011.   methods: in this cross-sectional study, 10 libraries, 16 study saloons, and 7 computer sites were selected. luminosity asse...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید