نتایج جستجو برای: co2

تعداد نتایج: 70752  

2015
Andreas Schindlbacher Werner Borken Ika Djukic Christian Brandstätter Christoph Spötl Wolfgang Wanek

Temperate forests provide favorable conditions for carbonate bedrock weathering as the soil CO2 partial pressure is high and soil water is regularly available. As a result of weathering, abiotic CO2 can be released and contribute to the soil CO2 efflux. We used the distinct isotopic signature of the abiotic CO2 to estimate its contribution to the total soil CO2 efflux. Soil cores were sampled f...

2007
Haris Riris James B. Abshire Graham Allan Xiaoli Sun S. Randy Kawa Jian-Ping Mao Mark Stephen Emily Wilson Michael A. Krainak

We report progress in assessing the feasibility of a new satellite-based laser-sounding instrument to measure CO2 concentrations in the lower troposphere from space. INTRODUCTION CO2 measurements from ice cores show that atmospheric CO2 concentrations are higher now than they have been in the past 400,000 years. It is becoming increasingly important to understand the nature and processes of the...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه علامه طباطبایی - دانشکده اقتصاد 1391

تولید و مصرف برق یکی از منابع اصلی انتشار co2 می باشد و بخش های تولیدی از استفاده کنندگان نهایی اصلی برق به شمار می روند. بدین منظور روش داده- ستانده با تحلیل حساسیت ترکیب شده تا مصرف مستقیم و غیرمستقیم برق در 40 بخش سه کشور ایران، ترکیه و آلمان بررسی گردد. در این مطالعه ابتدا فعالیت ها و بخش های صنعتی را که سهم بیش تری از تقاضای برق و انتشار co2 دارند را تعیین می کنیم. سپس اثر افزایش قیمت برق ...

پایان نامه :دانشگاه آزاد اسلامی - دانشگاه آزاد اسلامی واحد تهران مرکزی - دانشکده علوم پایه 1393

چکیده : هدف اصلی این پایان نامه، طراحی و ساخت فیلتر اپتیکی znse برای لیزر در طول موج 10600 نانومتر می باشد. در این پروژه،پس از مطالعه اولیه در مورد مفاهیم لیزر و فیلترهای این لیزر به خواص اپتیکی لایه های نازک و تکنیک های لایه نشانی می پردازیم. همچنین روش های مختلف آنالیز سطح از جمله طیف عبوری و بازتابی، sem جهت بررسی ساختارلایه بلوری و نمونه ها که مورد استفاده قرارگرفته اند،نیزمورد توجه قرار...

Journal: :journal of petroleum science and technology 2014
mohammad reza jafari nasr

the importance of energy crisis and global warming necessitates presenting strategies in order to decrease the amount of emissions as well as fuel consumption in large and complex industries such as refineries and petrochemical industries. generally, refinery steam networks are regarded as units which consume fuel enormously. in this paper, the steam network of tehran oil refinery is considered...

Journal: :journal of physical & theoretical chemistry 2008
b. khezri k. zare h. aghaie

bond-order conservation-morse potential (boc-mp) method is used to carry out the calculationon the co2+ h20 system. one of the best catalysts for methanol synthesis in catalytic reductionof co2 with h2o is cu/zno/a1203 whose surface is supported by with some amount of pd orga. reduction of co2 with h20 on cu will result in methanol formation; while on ni will lead tomethane formation. in the me...

Journal: :iranian chemical communication 2014
mahdieh ghobadifard mostafa khelghati ehsan zamani qasem maleki saeid farhadi

zno nanostructures of different methods and sizes were grown in a controlled manner using a simple hydrothermal and sonochemical technique. controlling the content of concentration and temperature of the reaction mixture, spherical nanoparticles zno structures could be synthesized at temperatures 100-150 °c with excellent reproducibility in solvothermal and at different power and time in sonoch...

Journal: :world journal of plastic surgery 0
ramtin kassir department of plastic surgery, hoag presbytarian university hospital, newport beach, ca, usa. johonna gilbreath department of plastic surgery, hoag presbytarian university hospital, newport beach, ca, usa. ali sajjadian 496 old newport blvd, suite #3, newport beach, ca 92663, usa.

rhinophyma is a severe late complication of rosacea, which is characterized by progressive hyperplasia of sebaceous glands and connective tissue involving the lower two-thirds of the nose. it can be an emotionally devastating disorder, and serve as a medium for occult cancers and other health problems. many surgical treatments have been advocated, as well as dermabrasion and laser therapy. in l...

Journal: :journal of skin and stem cell 0
abbas zamanian department of dermatology, rasoul akram hospital, iran university of medical sciences, tehran, iran elham behrangi department of dermatology, rasoul akram hospital, iran university of medical sciences, tehran, iran gholam hossein ghafarpour department of dermatology, rasoul akram hospital, iran university of medical sciences, tehran, iran golnaz mehran department of dermatology, rasoul akram hospital, iran university of medical sciences, tehran, iran romina espahbodi faculty of medicine, golestan university of medical sciences, gorgan, iran tanaz hoseinzade fakhim department of dermatology, rasoul akram hospital, iran university of medical sciences, tehran, iran; department of dermatology, rasoul akram hospital, iran university of medical sciences, tehran, iran. tel: +98-9123180244

conclusions our study showed that the triple therapy of nd: yag and nd: yag + co2 fractional and hydroquinone cream had high efficiency and low morbidity compared to twofold treatment with nd: yag and nd: yag + co2 fractional. results seventeen patients with melasma (14 females and three males) with mean (± sd) age of 38.47 (± 6.29) years (range 29 - 53) were included in this study. the only si...

2006

Carbon dioxide (CO2) is the gaseous end product of the aerobic metabolism of oxygen. CO2 is highly soluble in body tissues, and readily diffuses from cells to blood, where circulation transports it to the lungs for elimination. Divers often ignore carbon dioxide, as CO2 is a normal part of life. However, CO2 may have definite and detrimental effects if a diver accumulates an excessive amount of...

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