نتایج جستجو برای: n2o

تعداد نتایج: 4180  

2012
L. M. Zamora A. Oschlies H. W. Bange K. B. Huebert J. D. Craig A. Kock C. R. Löscher

The eastern tropical Pacific (ETP) is believed to be one of the largest marine sources of the greenhouse gas nitrous oxide (N2O). Future N2O emissions from the ETP are highly uncertain because oxygen minimum zones are expected to expand, affecting both regional production and consumption of N2O. Here we assess three primary uncertainties in how N2O may respond to changing O2 levels: (1) the rel...

Journal: :Isotopes in environmental and health studies 2003
O V Menyailo B A Hungate J Lehmann G Gebauer W Zech

The use of stable isotopes of N and O in N2O has been proposed as a way to better constrain the global budget of atmospheric N2O and to better understand the relative contributions of the main microbial processes (nitrification and denitrification) responsible for N2O formation in soil. This study compared the isotopic composition of N2O emitted from soils under different tree species in the Br...

ژورنال: :مجله دانشکده پزشکی اصفهان 0
محمد گلپرور دانشیار بیهوشی، گروه بیهوشی و مراق بتهای ویژه، دانشکده پزشکی، دانشگاه علوم پزشکی اصفهان، اصفهان، ایران علیرضا کوشا متخصص بیهوشی، بیمارستان دکتر غرضی، ملایر، ایران

مقدمه: یکی از روش های کمی اندازه گیری میزان آرامش و عمق بیهوشی (bis) bispectral index می باشد؛ در برخی مطالعات، اثر معکوس (پارادوکس) از n2o بر روی bis در بالغین شرح داده شده است. هدف از این مطالعه بررسی بروز اثرات پارادوکس n2o بر روی bis حین القای استنشاقی بیهوشی اطفال به وسیله ی هالوتان و ایزوفلوران بود. روش ها: در یک کارآزمایی بالینی 80 مورد از اطفال 6-1 ساله، asa ii و iکاندید عمل جراحی الکتی...

Journal: :Pediatric dentistry 2004
Ulrich Klein Brenda A Bucklin Thomas J Poulton Daniel Bozinov

PURPOSE Nitrous oxide (N2O) administration with nasal mask produces variable outcomes in dental patients. This study describes a novel sampling method to measure actual inspired/expired N2O concentrations ([N2O]). METHODS Fifteen adult volunteers (32.5 +/- 8.5 years) underwent placement of a nasopharyngeal probe. With a nasal mask, 100% oxygen (O2) was administered for 2 minutes. N2O was intr...

2014
Zhigao Sun Lingling Wang Xiaojie Mou Huanhuan Jiang Wanlong Sun

To investigate the spatial and seasonal variations of nitrous oxide (N2O) fluxes and understand the key controlling factors, we explored N2O fluxes and environmental variables in high marsh (HM), middle marsh (MM), low marsh (LM), and mudflat (MF) in the Yellow River estuary throughout a year. Fluxes of N2O differed significantly between sampling periods as well as between sampling positions. D...

Journal: :journal of agricultural science and technology 2015
y. k. li b. li w. z. guo x. p. wu

nitrous oxide (n2o) has significant impact on global warming and leads to the depletion of ozone in the stratosphere. agricultural soil is regarded as a major source of n2o emissions. in recent years, greenhouse grown vegetables have rapidly developed in china. although excessive fertilizer application in greenhouse vegetable production can result in increased n2o emissions, research data on su...

2016
Yanxia Nie Li Li Reika Isoda Mengcen Wang Ryusuke Hatano Yasuyuki Hashidoko

Dent corn Andisol at the Hokkaido University Shizunai Livestock Experimental Farm actively emits nitrous oxide (N2O). In order to screen for culturable and active N2O emitters with high N2O emission potential, soft gel medium containing excess KNO3 was inoculated with soil suspensions from farm soil samples collected at different land managements. Dominant bacterial colonies were searched for a...

2009
A. Freing D. W. R. Wallace T. Tanhua S. Walter H. W. Bange

[1] We use transit time distributions calculated from tracer data together with in situ measurements of N2O to estimate the concentration of biologically produced N2O ([N2O]xs) and N2O production rates in the central North Atlantic Ocean. Our approach to estimation of N2O production rates integrates the effects of potentially varying production and decomposition mechanisms along the transport p...

2016
Yuepeng Sun Qidong Yin Bo Li Guangxue Wu

Nitrous oxide (N2O) generation and emission may hamper the wide application of denitrifying phosphorus removal technology. In this study, batch experiments were carried out to investigate the effect of nitrite on N2O generation and emission during denitrifying phosphorus removal. Compared to NO3-N, N2O emission was much higher when NO2-N was used as the electron acceptor. N2O emission had no ob...

2017
Lisa Brase Hermann W. Bange Ralf Lendt Tina Sanders Kirstin Dähnke

Nitrous oxide (N2O) is one of the most important greenhouse gases and a major sink for stratospheric ozone. Estuaries are sites of intense biological production and N2O emissions. We aimed to identify hot spots of N2O production and potential pathways contributing to N2O concentrations in the surface water of the tidal Elbe estuary. During two research cruises in April and June 2015, surface wa...

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