搜索结果: 1-15 共查到“理学 ammonium”相关记录74条 . 查询时间(0.062 秒)
The importance of Dissimilatory Nitrate reduction to ammonium (DNra) in the Nitrogen cycle of coastal ecosystems
Dissimilatory Nitrate Nitrogen cycle
2015/7/16
Until recently, it was believed that biological assimilation and gaseous nitrogen (N) loss through denitrification were the two major fates of nitrate entering or produced within most coastal ecosyste...
Modeling atmospheric ammonia and ammonium using a stochastic Lagrangian air quality model (STILT-Chem v0.7)
Modeling atmospheric ammonia ammonium stochastic Lagrangian air quality model
2014/12/16
A new chemistry module that simulates atmospheric ammonia (NH3) and ammonium (NH+4) was incorporated into a backward-in-time stochastic Lagrangian air quality model (STILT-Chem) that was originally de...
At different times of the year, prevailing winds blow into Bermuda from open ocean to the south or from the continental United States — an ideal laboratory for studying pollution generated by human ac...
Nitrogen fixation and dissimilatory nitrate reduction to ammonium (DNRA) support nitrogen dynamics in Texas estuaries
Nitrogen fi xation dissimilatory nitrate
2014/4/30
We conducted continuous-flow experiments on intact sediment cores from Laguna Madre, Sabine Lake, East
Matagorda Bay, and Nueces Estuary to evaluate internal nitrogen (N) sources, sinks, and re...
Anaerobic ammonium oxidation (anammox) bacteria and sulfide-dependent denitrifiers coexist in the water column of a meromictic south-alpine lake
Anaerobic ammonium oxidation bacteria sulfide-dependent denitrifiers coexist in the water column a meromictic south-alpine lake
2014/4/2
In addition to organotrophic denitrification, alternative pathways, such as anaerobic ammonium oxidation(anammox) or sulfide-dependent denitrification may be important modes for the removal of fixed n...
Ammonium uptake and dinitrogen fixation by the unicellular nanocyanobacterium Crocosphaera watsonii in nitrogen-limited continuous cultures
nanocyanobacterium Crocosphaera Ammonium uptake
2014/4/2
Ammonium uptake and nitrogen (N) fixation of the unicellular nanocyanobacterium Crocosphaera watsonii
isolated from the western subtropical North Pacific were determined in N-limited continuous cultu...
The role of hydrodynamics in structuring in situ ammonium uptake within a submerged macrophyte community
nutrients water fl ow patchiness Cymodocea nodosa Caulerpa prolifera
2014/4/1
In low-nutrient, macrophyte-dominated coastal zones, benthic ammonium (NH4
+
) uptake may be influenced by the structural properties of plant canopies via their effect on near-bed hydrodynamic...
Fast removal of ammonium ion using a hydrogel optimized with response surface methodology
Adsorption Ammonium ion Box–Behnken design Hydrogel Response surface methodology
2011/12/14
Response surface methodology (RSM) based on a three-level, three-variable, Box–Behnken design (BBD) was used to optimize the preparation parameters of a hydrogel consisted of polyvinyl alcohol (PVA),a...
Comparative effects of urea, ammonium, and nitrate on phytoplankton abundance, community composition, and toxicity in hypereutrophic freshwaters
Comparative effects of urea ammonium nitrate
2014/4/4
Dissolved nitrogen (N) as urea ([NH2
]2CO), nitrate (NO{
3
), and ammonium (NHz
4
) was added to naturally
phosphorus (P)-rich lake water (up to 175 mg P L21
) to test the hypotheses that pollu...
Molecular evidence for anaerobic ammonium–oxidizing (anammox) bacteria in continental shelf and slope sediments off northwest Africa
Molecular evidence anaerobic ammonium–oxidizing bacteria in continental shelf slope sediments off northwest Africa
2014/4/16
The presence and abundance of anaerobic ammonium–oxidizing (anammox) bacteria was investigated in continental shelf and slope sediments (300–3000 m water depth) off northwest Africa in a combined appr...
Amine exchange into ammonium bisulfate and ammonium nitrate nuclei
Amine ammonium bisulfate ammonium nitrate nuclei
2010/8/12
The exchange kinetics and thermodynamics of amines for ammonia in small (1–2 nm diameter) ammonium bisulfate and ammonium nitrate clusters were investigated using electrospray ionization Fourier trans...
Depositional ice nucleation on solid ammonium sulfate and glutaric acid particles
Depositional ice nucleation solid ammonium sulfate glutaric acid particles
2010/3/16
Heterogeneous ice nucleation on solid ammonium sulfate and glutaric acid particles was studied using optical microscopy and Raman spectroscopy. Optical microscopy was used to detect selective nucleati...
The reaction of free chlorine with tertiary ammonium or amine compounds in aqueous solution was studied by the amperometry at a rotating Pt-disk electrode. The amperometric method can be applied to fo...
Thermoanalytical studies of natural potassium, sodium and ammonium alunites
Alunite thermal analysis, Controlled rate thermal analysis, Dehydration, Dehydroxylation
2011/11/10
Dynamic and controlled rate thermal analysis (CRTA) has been used to characterise alunites of formula [M(Al)3(SO4)2(OH)6] where M+ is the cations K+, Na+ or NH4 +. Thermal decomposition occurs in a se...
Oxorhenium(V)-mediated syntheses and structures of oxypyridinium-ammonium zwitterions
Oxorhenium(V) oxypyridinium-ammonium zwitterions
2010/4/8
Treatment of N,N-bis(2-hydroxybenzyl)-2-(2-aminoethyl) dimethylamine (H2had) with trans-[ReO2(py)4]I in acetone affords the iodide salts of the oxypyridinium-ammonium zwitterions N1-(2-hydroxybenzyl)-...