نتایج جستجو برای: n fixation
تعداد نتایج: 1024085 فیلتر نتایج به سال:
N(2) fixation by Chlorobium phaeobacteroides from Lake Kinneret was dependent on ammonia concentration and light intensity. In the thermocline of Lake Kinneret, N(2) fixation and photosynthesis were low. It was concluded that the bacteria do not contribute significantly to the organic nitrogen load of the lake.
Nitrogen fixation, the enzymatic conversion of atmospheric N (N 2) to ammonia (NH 3), is a microbially mediated process by which "new" N is supplied to N-deficient water bodies. Certain bloom-forming cyanobacterial species are capable of conducting N 2 fixation; hence, they are able to circumvent N limitation in these waters. However, this anaerobic process is highly sensitive to oxygen, and si...
Terminal iron nitrides (Fe≡N) have been proposed as intermediates of Fe-mediated nitrogen fixation, and well-defined synthetic characterized in high oxidation states, including FeIV, FeV, FeVI. This study reports the generation low temperature characterization a terminally bound iron(III) nitride, P3BFe(N) (P3B=tris(o-diisopropylphosphinophenyl)borane), which is intermediate iron-mediated fixat...
Annual rates of N2 fixation were measured over 3 yr (1998–2000) at an open water station (BY31) and 2 coastal stations (H4 and X1) in the Baltic Sea. This is the first report on depthintegrated rates of N2 fixation from more than one complete growth season in the Baltic Sea. Annual estimates of N2 fixation ranged from 56 000 to 125 000 t N in the Baltic Proper, and 18 000 to 162 000 t N at the ...
The near ubiquitous distribution of nifH genes in sediments sampled from 14 high-temperature (48.0-89.0°C) and acidic (pH 1.90-5.02) geothermal springs in Yellowstone National Park suggested a role for the biological reduction of dinitrogen (N(2)) to ammonia (NH(3)) (e.g. nitrogen fixation or diazotrophy) in these environments. nifH genes from these environments formed three unique phylotypes t...
PURPOSE. To compare the efficacy of locking plate fixation with and without inferomedial screws in maintaining the reduction of a proximal humeral fracture. METHODS. 22 synthetic humerus models were used. A standardised 3-part proximal humeral fracture with a 4-mm wedge segment was created and fixed with a locking plate and screws with (n=11) and without (n=11) inferomedial screws. The intrafra...
BACKGROUND Ligament reconstruction is a common procedure in orthopedic surgery. Although several popular techniques are currently in use, new methods are proposed for secure fixation of the tendon graft into the bone tunnel. PURPOSES We sought to introduce our new technique of Bashti bone plug for fixation of soft tissue graft in anterior cruciate ligament (ACL) reconstruction and to compare ...
BACKGROUND Expandable screws have greater pullout strength than conventional screws. The purpose of this study was to compare the biomechanical stability provided by a new built-in expandable anterior spinal fixation system with that of 2 commonly used anterior fixation systems, the Z-Plate and the Kaneda, in a porcine partial vertebral corpectomy model. METHODS Eighteen porcine thoracolumbar...
Hydrogen sulphide (H2S), as a signalling molecule, regulates the process of plant growth and development. H2S is involved in establishment legume rhizobial symbiotic relationship, but little known about role during nodule senescence. We studied function senescence Glycine max-Sinorhizobium fredii system. Physiological biochemical methods were used to modulate nitrogen fixation, structure, senes...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید