keyword
MENU ▼
Read by QxMD icon Read
search

n2o

keyword
https://www.readbyqxmd.com/read/28212019/complete-nutrient-removal-coupled-to-nitrous-oxide-production-as-a-bioenergy-source-by-denitrifying-polyphosphate-accumulating-organisms
#1
Han Gao, Miaomiao Liu, James S Griffin, Longcheng Xu, Da Xiang, Yaniv D Scherson, Wen-Tso Liu, George F Wells
Coupled Aerobic-anoxic Nitrous Decomposition Operation (CANDO) is a promising emerging bioprocess for wastewater treatment that enables direct energy recovery from nitrogen (N) in three steps: (1) ammonium oxidation to nitrite; (2) denitrification of nitrite to nitrous oxide (N2O); and (3) N2O conversion to N2 with energy generation. However, CANDO does not currently target phosphorus (P) removal. Here, we demonstrate that denitrifying polyphosphate accumulating organism (PAO) enrichment cultures are capable of catalyzing simultaneous biological N and P removal coupled to N2O generation in a 2nd generation CANDO process, CANDO+P...
February 17, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28209538/new-insight-into-the-catalytic-cycle-about-epoxidation-of-alkenes-by-n2o-over-a-mn-substituted-keggin-type-polyoxometalate
#2
Meng-Xu Jiang, Chun-Guang Liu
Although epoxidation of alkenes by N2O catalyzed by Mn-substituted polyoxometalates (POMs) has been studied both experimental and theoretical methods, a complete catalytic cycle has not been established currently. In the present paper, density functional theory (DFT) calculations were employed to explore possible reaction mechanism about this catalytic cycle. Our DFT studies reveal that the reaction pathway starts from a low-valent Keggin-type POM aquametal derivative [PW11O39Mn(III)H2O](4-). In the presence of N2O pressure, the formation of the active catalytic species [PW11O39Mn(V)O](4-) involves a ligand-substituted reaction about replacement of the aqua ligand with N2O to generation of POM/N2O adduct [PW11O39Mn(III)ON2](4-) and dissociation of N2 from this adduct...
December 21, 2016: Journal of Molecular Graphics & Modelling
https://www.readbyqxmd.com/read/28208256/effects-of-drift-gas-selection-on-the-ambient-temperature-ion-mobility-mass-spectrometry-analysis-of-amino-acids
#3
Kimberly L Davidson, Matthew F Bush
Ion mobility (IM) separates ions based on their response to an electric field in the presence of a drift gas. Because of its speed and sensitivity, the integration of IM and mass spectrometry (MS) offers many potential advantages for the analysis of small molecules. To determine the effects that drift gas selection has on the information content of IM separations, absolute collision cross sections (Ω) with He, N2, Ar, CO2, and N2O were measured for the 20 common amino acids using low-pressure, ambient-temperature ion mobility experiments performed in a radio frequency-confining drift cell...
February 7, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28206894/survey-of-american-academy-of-pediatric-dentistry-on-nitrous-oxide-and-sedation-20-years-later
#4
Stephen Wilson, Elizabeth S Gosnell
PURPOSE: The purpose of this study was to survey the membership of the American Academy of Pediatric Dentistry (AAPD) and determine the current status of nitrous oxide (N2O) utilization in their dental practices while also comparing the findings to a similar survey completed 20 years ago. METHODS: A 55-item questionnaire on the use of N2O was sent to the AAPD membership. RESULTS: The total number of respondents was 1,632 (26 percent). Sixty-two percent are board-certified, 97 percent use N2O in their office, 18 percent indicated greater than 80 percent of their patient pool required N2O versus six percent in 1996...
October 15, 2016: Pediatric Dentistry
https://www.readbyqxmd.com/read/28205581/pathways-of-n-removal-and-n2o-emission-from-a-one-stage-autotrophic-n-removal-process-under-anaerobic-conditions
#5
Kai Li, Fang Fang, Han Wang, Chao Wang, Youpeng Chen, Jinsong Guo, Xixi Wang, Fuyang Jiang
To investigate the pathways of nitrogen (N) removal and N2O emission in a one-stage autotrophic N removal process during the non-aeration phase, biofilm from an intermittent aeration sequencing batch biofilm reactor (SBBR) and organic carbon-free synthetic wastewater were applied to two groups of lab-scale batch experiments in anaerobic conditions using a (15)N isotopic tracer and specific inhibitors, respectively. Then, the microbial composition of the biofilm was analysed using high-throughput sequencing...
February 16, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28197774/popliteal-block-for-lower-limb-surgery-in-children-with-cerebral-palsy-effect-on-sevoflurane-consumption-and-postoperative-pain-a-randomized-double-blinded-controlled-trial
#6
Derya Ozkan, Emel Gonen, Taylan Akkaya, Mesut Bakir
PURPOSE: The aim of this study was to evaluate the effects of a preoperative popliteal block on sevoflurane consumption, postoperative pain, and analgesic consumption in children with cerebral palsy (CP) following lower limb surgery. METHODS: Fifty-four patients undergoing lower limb surgery were randomized to receive either a popliteal block + general anaesthesia (group P, n = 27) or general anaesthesia without a popliteal block (group C, n = 27). After anesthesia induction with 50% N2O, O2, and 8% sevoflurane, a popliteal block was given to group P patients with ultrasound guidance as a single dose of 0...
February 14, 2017: Journal of Anesthesia
https://www.readbyqxmd.com/read/28192496/impact-of-nitrogen-fertilization-on-soil-atmosphere-greenhouse-gas-exchanges-in-eucalypt-plantations-with-different-soil-characteristics-in-southern-china
#7
Kai Zhang, Hua Zheng, Falin Chen, Ruida Li, Miao Yang, Zhiyun Ouyang, Jun Lan, Xuewu Xiang
Nitrogen (N) fertilization is necessary to sustain productivity in eucalypt plantations, but it can increase the risk of greenhouse gas emissions. However, the response of soil greenhouse gas emissions to N fertilization might be influenced by soil characteristics, which is of great significance for accurately assessing greenhouse gas budgets and scientific fertilization in plantations. We conducted a two-year N fertilization experiment (control [CK], low N [LN], middle N [MN] and high N [HN] fertilization) in two eucalypt plantations with different soil characteristics (higher and lower soil organic carbon sites [HSOC and LSOC]) in Guangxi, China, and assessed soil-atmosphere greenhouse gas exchanges...
2017: PloS One
https://www.readbyqxmd.com/read/28192347/predicting-n2o-emissions-from-nitrifying-and-denitrifying-biofilms-a-modeling-study
#8
Fabrizio Sabba, Cristian Picioreanu, Joshua P Boltz, Robert Nerenberg
Wastewater treatment plants can be significant sources of nitrous oxide (N2O), a potent greenhouse gas. While our understanding of N2O emissions from suspended-growth processes has advanced significantly, less is known about emissions from biofilm processes. Biofilms may behave differently due to their substrate gradients and microbial stratification. In this study, we used mathematical modeling to explore the mechanisms of N2O emissions from nitrifying and denitrifying biofilms. Our ammonia-oxidizing bacteria biofilm model suggests that N2O emissions from biofilm can be significantly greater than from suspended-growth systems...
February 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
https://www.readbyqxmd.com/read/28192343/comparison-of-different-two-pathway-models-for-describing-the-combined-effect-of-do-and-nitrite-on-the-nitrous-oxide-production-by-ammonia-oxidizing-bacteria
#9
Longqi Lang, Mathieu Pocquet, Bing-Jie Ni, Zhiguo Yuan, Mathieu Spérandio
The aim of this work is to compare the capability of two recently proposed two-pathway models for predicting nitrous oxide (N2O) production by ammonia-oxidizing bacteria (AOB) for varying ranges of dissolved oxygen (DO) and nitrite. The first model includes the electron carriers whereas the second model is based on direct coupling of electron donors and acceptors. Simulations are confronted to extensive sets of experiments (43 batches) from different studies with three different microbial systems. Despite their different mathematical structures, both models could well and similarly describe the combined effect of DO and nitrite on N2O production rate and emission factor...
February 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
https://www.readbyqxmd.com/read/28190665/intranasal-fentanyl-and-inhaled-nitrous-oxide-for-fracture-reduction-the-fan-observational-study
#10
J Hoeffe, E Doyon Trottier, B Bailey, D Shellshear, M Lagacé, C Sutter, G Grimard, R Cook, F E Babl
INTRODUCTION: Procedural sedation and analgesia (PSA) are frequently used for fracture reduction in pediatric emergency departments (ED). Combining intranasal (IN) fentanyl with inhalation of nitrous oxide (N2O) allow for short recovery time and obviates painful and time-consuming IV access insertions. METHODS: We performed a bicentric, prospective, observational cohort study. Patients aged 4-18years were included if they received combined PSA with IN fentanyl and N2O for the reduction of mildly/moderately displaced fracture or of dislocation...
January 5, 2017: American Journal of Emergency Medicine
https://www.readbyqxmd.com/read/28183759/complete-genome-sequences-of-two-acetylene-fermenting-pelobacter-acetylenicus-strains
#11
John M Sutton, Shaun M Baesman, Janna L Fierst, Amisha T Poret-Peterson, Ronald S Oremland, Darren S Dunlap, Denise M Akob
Acetylene fermentation is a rare metabolism that was serendipitously discovered during C2H2-block assays of N2O reductase. Here, we report the genome sequences of two type strains of acetylene-fermenting Pelobacter acetylenicus, the freshwater bacterium DSM 3246 and the estuarine bacterium DSM 3247.
February 9, 2017: Genome Announcements
https://www.readbyqxmd.com/read/28166085/when-the-laughing-stops-subacute-combined-spinal-cord-degeneration-caused-by-laughing-gas-use
#12
Annemiek Buizert, Ruby Sharma, Hille Koppen
Here we describe a case of subacute combined spinal cord degeneration caused by nitrous oxide (N2O, laughing gas) use. Because of its euphoric effects, the use of N2O has become increasingly popular in recent years. Unfortunately, the use of N2O leads to inactivation of vitamin B12. Vitamin B12 plays an essential role in the synthesis and maintenance of myelin, a fatty substance that surrounds nerve cells and is crucial for their functioning. Deficiency of vitamin B12 could typically result in degeneration of posterior and lateral columns of the spinal cord...
February 3, 2017: Journal of Addiction Medicine
https://www.readbyqxmd.com/read/28165773/greenhouse-gas-emissions-from-a-cu-contaminated-soil-remediated-by-in-situ-stabilization-and-phytomanaged-by-a-mixed-stand-of-poplar-willows-and-false-indigo-bush
#13
M Šimek, D Elhottová, M Mench, L Giagnoni, P Nannipieri, G Renella
Phytomanagement of trace element-contaminated soils can reduce the soil toxicity and restore the soil ecological functions, including the soil gas exchange with the atmosphere. We studied the emission rate of the greenhouse gases (GHG) CO2, CH4 and N2O, and the potential CH4 oxidation, denitrification activity (DEA) and glucose mineralization of a Cu-contaminated soil amended with dolomitic limestone and compost, alone or in combination, after a 2 year-phytomanagement with a mixed stand of Populus nigra, Salix viminalis, S...
February 6, 2017: International Journal of Phytoremediation
https://www.readbyqxmd.com/read/28164698/hybrid-nitrous-oxide-production-from-partial-nitrifying-bioreactor-hydroxylamine-interactions-with-nitrite
#14
Akihiko Terada, Sho Sugawara, Keisuke Hojo, Yuki Takeuchi, Shohei Riya, Willie F Harper, Tomoko Yamamoto, Megumi Kuroiwa, Kazuo Isobe, Chie Katsuyama, Yuichi Suwa, Keisuke Koba, Masaaki Hosomi
The goal of this study was to elucidate the mechanisms of N2O production from a bioreactor for partial nitrification (PN). Ammonia-oxidizing bacteria (AOB) enriched from a sequencing batch reactor (SBR) were subjected to N2O production pathway tests. The N2O pathway test was initiated by supplying an inorganic medium to ensure an initial NH4(+)-N concentration of 160 mg-N/L, followed by (15)NO2(-) (20 mg-N/L) and dual (15)NH2OH (each 17 mg-N/L) spikings to quantify isotopologs of gaseous N2O ((44)N2O, (45)N2O, and (46)N2O)...
February 6, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28161628/application-of-biochar-and-nitrogen-influences-fluxes-of-co2-ch4-and-n2o-in-a-forest-soil
#15
Iain Hawthorne, Mark S Johnson, Rachhpal S Jassal, T Andrew Black, Nicholas J Grant, Sean M Smukler
Nitrogen (N) fertilization of forests for increasing carbon sequestration and wood volume is expected to influence soil greenhouse gas (GHG) emissions, especially to increase N2O emissions. As biochar application is known to affect soil GHG emissions, we investigated the effect of biochar application, with and without N fertilization, to a forest soil on GHG emissions in a controlled laboratory study. We found that biochar application at high (10%) application rates increased CO2 and N2O emissions when applied without urea-N fertilizer...
February 2, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28161179/methane-production-ruminal-fermentation-characteristics-nutrient-digestibility-nitrogen-excretion-and-milk-production-of-dairy-cows-fed-conventional-or-brown-midrib-corn-silage
#16
F Hassanat, R Gervais, C Benchaar
The objective of this study was to examine the effect of replacing conventional corn silage (CCS) with brown midrib corn silage (BMCS) in dairy cow diets on enteric CH4 emission, nutrient intake, digestibility, ruminal fermentation characteristics, milk production, and N excretion. Sixteen rumen-cannulated lactating cows used in a crossover design (35-d periods) were fed (ad libitum) a total mixed ration (forage:concentrate ratio = 65:35, dry matter basis) based (59% dry matter) on either CCS or BMCS. Dry matter intake and milk yield increased when cows were fed BMCS instead of CCS...
February 1, 2017: Journal of Dairy Science
https://www.readbyqxmd.com/read/28160658/nitrogen-removal-via-nitrite-in-a-partial-nitrification-sequencing-batch-biofilm-reactor-treating-high-strength-ammonia-wastewater-and-its-greenhouse-gas-emission
#17
Dong Wei, Keyi Zhang, Huu Hao Ngo, Wenshan Guo, Siyu Wang, Jibin Li, Fei Han, Bin Du, Qin Wei
In present study, the feasibility of partial nitrification (PN) process achievement and its greenhouse gas emission were evaluated in a sequencing batch biofilm reactor (SBBR). After 90days' operation, the average effluent NH4(+)-N removal efficiency and nitrite accumulation rate of PN-SBBR were high of 98.2% and 87.6%, respectively. Both polysaccharide and protein contents were reduced in loosely bound extracellular polymeric substances (LB-EPS) and tightly bound EPS (TB-EPS) during the achievement of PN-biofilm...
January 25, 2017: Bioresource Technology
https://www.readbyqxmd.com/read/28153401/the-influence-of-straw-returning-on-n2o-emissions-from-a-maize-wheat-field-in-the-north-china-plain
#18
Yizhen Zhou, Yuanyuan Zhang, Di Tian, Yujing Mu
Crop straw returning has become a prevailing cultivation practice in the vast area of the North China Plain (NCP), while few investigations about its influence on nitrous oxide (N2O) emission have been conducted. In this study, N2O emissions from an agricultural field in the NCP with and without straw returning were comparably investigated by using static chambers in two consecutive maize-wheat growing seasons from June 2010 to June 2012. Compared with the NP treatment (compound nitrogen fertilizer only), the cumulative N2O emission from the SP treatment (compound nitrogen fertilizer plus straw) increased about 150% during the maize season in 2010, but decreased by about 35% during the maize season in 2011...
January 30, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28152458/dynamics-and-emissions-of-n2o-in-groundwater-a-review
#19
REVIEW
Anna Jurado, Alberto V Borges, Serge Brouyère
This work reviews the concentrations, the dynamics and the emissions of nitrous oxide (N2O) in groundwater. N2O is an important greenhouse gas (GHG) and the primary stratospheric ozone depleting substance. The major anthropogenic source that contributes to N2O generation in aquifers is agriculture because the use of fertilizers has led to the widespread groundwater contamination by inorganic nitrogen (N) (mainly nitrate, NO3(-)). Once in the aquifer, this inorganic N is transported and affected by several geochemical processes that produce and consume N2O...
January 30, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28150149/effects-of-maize-stover-and-its-derived-biochar-on-greenhouse-gases-emissions-and-c-budget-of-brown-earth-in-northeast-china
#20
Xu Yang, Yu Lan, Jun Meng, Wenfu Chen, Yuwei Huang, Xiaoyi Cheng, Tianyi He, Ting Cao, Zunqi Liu, Linlin Jiang, Jiping Gao
Concerns regarding rising population levels and the impacts of atmospheric greenhouse gas (GHG) emissions on world climate have encouraged effective alternative methods to increase agricultural production while mitigating climate change. Soil GHG emissions from maize (Zea mays L.) fields treated with stover and a stover-derived biochar amendment during two consecutive maize growing seasons were studied in a brown earth soil type in Liaoning, China. We considered three treatments: CK (basal application of mineral NPK fertilizer; 120 kg N ha(-1), 60 kg P2O5 ha(-1), and 60 kg K2O ha(-1), respectively), ST (maize stover application; 7...
February 1, 2017: Environmental Science and Pollution Research International
keyword
keyword
41395
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"