Photosynthetic Acclimation to Low Carbon Concentrations in Chlamydomonas reinhardtii

1990 ◽  
pp. 3235-3242
Author(s):  
Göran Samuelsson ◽  
Kristin Palmqvist ◽  
Zakir Ramazanov ◽  
Lars-Göran Sundblad
Keyword(s):  
Chlamydomonas Reinhardtii ◽  
Photosynthetic Acclimation ◽  
Low Carbon ◽  
Carbon Concentrations

Impact of climate and bulking materials on characteristics of compost from ecological toilets

2012 ◽  
Vol 2 (2) ◽  
pp. 79-86 ◽  
Author(s):  
James W. McKinley ◽  
Rebecca E. Parzen ◽  
Álvaro Mercado Guzmán
Keyword(s):  
Low Carbon ◽  
Pathogen Inactivation ◽  
High Ph ◽  
Moisture Contents ◽  
Urine Diversion ◽  
Ph Values ◽  
Dominant Process ◽  
Nitrogen Ratio ◽  
Storage Times ◽  
Carbon Concentrations

Urine-diversion dehydration toilets (UDDT) are common throughout the developing world, and the toilet product is widely used as compost. There is no comprehensive research to date that characterizes the compost to determine its quality, extent of pathogen inactivation, and the effects of climate and bulking materials on the compost. Compost was collected from 45 UDDT in Bolivia and analyzed for physical, chemical, and biological parameters. Eighty percent and 56% of samples did not meet acceptable compost guidelines for moisture content and pH, respectively, indicating desiccation was the dominant process in UDDT. Bulking materials significantly impacted compost characteristics in terms of pH, carbon, carbon-to-nitrogen ratio, and carbon stability (P < 0.05). Composts with ash exhibited, on average, low carbon concentrations (4.9%) and high pH values (9.7), which can be harmful to plants and composting microorganisms. Composts with sawdust exhibited, on average, high carbon concentrations (40.0%) and carbon-to-nitrogen ratios (31.0). Climate had no significant impact on chemical characteristics, however composts from humid regions had significantly higher moisture contents (34.4%) than those from arid climates (24.8%) (P < 0.05). Viable Ascaris lumbricoides ova were identified in 31% of samples, including samples with high pH, low moisture contents, and long storage times.

Development of Low Carbon Microalloyed Ultra High Strength Steels

2005 ◽  
Vol 500-501 ◽  
pp. 551-558 ◽  
Author(s):  
A. Ghosh ◽  
Brajendra Mishra ◽  
Subrata Chatterjee
Keyword(s):  
Room Temperature ◽  
High Strength Steels ◽  
High Strength ◽  
Low Carbon ◽  
Hsla Steels ◽  
Finish Rolling ◽  
Ultra High Strength Steels ◽  
Rolling Temperatures ◽  
Carbon Microalloyed ◽  
Carbon Concentrations

In the present study HSLA steels of varying carbon concentrations, alloyed with Mn, Ni, Cr, Mo, Cu and micro-alloyed with Nb and Ti were subjected to different finish rolling temperatures from 850oC to 750oC in steps of 50oC. The microstructure of the steel predominantly shows martensite. Fine twins, strain induced precipitates in the martensite lath along with e-Cu precipitates are observed in the microstructure. With an increase in carbon content the strength value increases from 1200MPa UTS to 1700MPa UTS with a negligible reduction in elongation. Impact toughness values of 20-26 joules at room temperature and −40oC were obtained in sub-size samples.

Influence of Carbon Concentrations in Reducing Co and Cr Ions Release in Cobalt Based Implant: A Preliminary Report

2013 ◽  
Vol 845 ◽  
pp. 462-466 ◽  
Author(s):  
H. Mas-Ayu ◽  
S. Izman ◽  
Mohammed Rafiq Abdul Kadir ◽  
Rosdi Daud ◽  
A. Shah ◽  
...  
Keyword(s):  
Metal Ions ◽  
Oxide Layer ◽  
Inductively Coupled Plasma ◽  
Atmospheric Condition ◽  
Immersion Test ◽  
Low Carbon ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Plasma Mass Spectrometry ◽  
Carbon Concentrations

The releases of harmful ions from cobalt based alloy to host tissues have raised significant health concerns. Carbon contents in this alloy may influence ions release but has yet investigated. It is hypothesized that carbon contents in this alloy will help the formation of oxide layer during thermal oxidation process and hence reducing the release of Co/Cr ions after implantation. In this study, Co-Cr-Mo alloy with carbon concentrations of 0.03% and 0.24% were oxidized at 1050°C for 3 hours under atmospheric condition. The oxidized substrates were characterized under FESEM and subjected to circulating immersion test in simulated body fluid (SBF) for 21 days. Metal ions release was measured using inductively coupled plasma-mass spectrometry (ICP-MS) at day 0, 7, 14 and 21. Oxidized high carbon samples show denser and a more uniform oxide layer than samples with low carbon contents. It is found that compact oxide structure promotes less metal ions release during immersion.

On the quantitative EDS analysis of low carbon concentrations in analytical TEM

1993 ◽  
Vol 49 (1-4) ◽  
pp. 220-224 ◽  
Author(s):  
W. Wunderlich ◽  
A.H. Foitzik ◽  
A.H. Heuer
Keyword(s):  
Low Carbon ◽  
Eds Analysis ◽  
Analytical Tem ◽  
Carbon Concentrations

Impact of low carbon concentrations on the electrical properties of highly boron doped SiGe layers

1997 ◽  
Vol 71 (11) ◽  
pp. 1522-1524 ◽  
Author(s):  
H. J. Osten ◽  
G. Lippert ◽  
P. Gaworzewski ◽  
R. Sorge
Keyword(s):  
Electrical Properties ◽  
Low Carbon ◽  
Boron Doped ◽  
Carbon Concentrations

The diffusion of carbon into tungsten and molybdenum at low carbon concentrations

1965 ◽  
Vol 3 (4) ◽  
pp. 288-291 ◽  
Author(s):  
L. N. Aleksandrov ◽  
V. Ya. Shchelkonogov
Keyword(s):  
Low Carbon ◽  
Carbon Concentrations

Experimental Lakes Area: Whole-Lake Experiments in Eutrophication

1974 ◽  
Vol 31 (5) ◽  
pp. 937-953 ◽  
Author(s):  
D. W. Schindler ◽  
E. J. Fee
Keyword(s):  
Algal Blooms ◽  
Large Scale ◽  
The Other ◽  
Phosphorus Fertilization ◽  
Low Carbon ◽  
Nitrogen And Phosphorus ◽  
Experimental Lakes Area ◽  
Carbon And Nitrogen ◽  
Small Phytoplankton ◽  
Carbon Concentrations

The following whole-lake experiments are described:Lake 227, fertilized for 5 yr with phosphate and nitrate, has shown an enormous increase in phytoplankton, in spite of low carbon concentrations. The carbon necessary for production of algal blooms was found to invade from the atmosphere.Lake 304, eutrophied by fertilization with phosphorus, nitrogen, and carbon in 1971 and 1972, recovered rapidly when phosphorus fertilization was terminated.Lake 226 was split in half with a curtain. One half was fertilized with carbon and nitrogen and the other was fertilized with phosphorus, carbon, and nitrogen. The half of the lake receiving phosphorus developed an algal bloom and the other half did not.Lake 302, which had carbon, nitrogen, and phosphorus added to the hypolimnion, did not develop algal blooms in summer. Small phytoplankton blooms were found under ice in early December, but all nutrients were efficiently sedimented and unavailable the following year.The above studies illustrate clearly that phosphorus control is an efficient primary step in preventing or checking eutrophication problems.A review of other published and ongoing studies in the Experimental Lakes Area is given, illustrating the role which large-scale experiments can play in interpreting environmental problems.

scholarly journals The Structure, Morphology, and Mechanical Properties of Ta-Hf-C Coatings Deposited by Pulsed Direct Current Reactive Magnetron Sputtering

Coatings ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 212 ◽  
Author(s):  
Alexis de Monteynard ◽  
Huan Luo ◽  
Mohamed Chehimi ◽  
Jaafar Ghanbaja ◽  
Sofiane Achache ◽  
...  
Keyword(s):  
Residual Stresses ◽  
Magnetron Sputtering ◽  
Carbon Content ◽  
Direct Current ◽  
Optical Emission ◽  
Low Carbon ◽  
Tem Analysis ◽  
Carbide Phases ◽  
Pulsed Direct Current ◽  
Carbon Concentrations

Ta, Hf, TaCx, HfCx, and TaxHf1-xCy coatings were deposited by reactive pulsed Direct Current (DC) magnetron sputtering of Ta or Hf pure metallic targets in Ar plus CH4 gas mixtures. The properties have been investigated as a function of the carbon content, which is tuned via the CH4 flow rate. The discharge was characterized by means of Optical Emission Spectroscopy and, in our conditions, both Ta-C and Hf-C systems seem to be weakly reactive. The structure of the as-deposited pure tantalum film is metastable tetragonal β-Ta. The fcc-MeCx carbide phases (Me = Ta or Hf) are {111} textured at low carbon concentrations and then lose their preferred orientation for higher carbon concentrations. Transmission Electron Microscopy (TEM) analysis has highlighted the presence of an amorphous phase at higher carbon concentrations. When the carbon content increases, the coating’s morphology is first compact-columnar and becomes glassy because of the nano-sized grains and then returns to an open columnar morphology for the higher carbon concentrations. The hardness and Young’s modulus of TaCx coatings reach 36 and 405 GPa, respectively. For HfCx coatings, these values are 29 and 318 GPa. The MeCx coating residual stresses increase with the addition of carbon (from one-hundredth of 1 MPa to 1.5 GPa approximately). Nevertheless, the columnar morphology at a high carbon content allows the residual stresses to decrease. Concerning TaxHf1-xCy coatings, the structure and the microstructure analyses have revealed the creation of a nanostructured coating, with the formation of an fcc superlattice. The hardness is relatively constant independently of the chemical composition (22 GPa). The residual stress was strongly reduced compared to that of binary carbides coatings, due to the rotation of substrates.

Sign in / Sign up

Export Citation Format

Share Document