Results 71 to 80 of about 255,270 (305)

Clouds, Clumps, Cores & Comets - a Cosmic Chemical Connection?

, 2008
We discuss the connection between the chemistry of dense interstellar clouds and those characteristics of cometary matter that could be remnants of it. The chemical evolution observed to occur in molecular clouds is summarized and a model for dense core ...
Charnley, S. B., Rodgers, S. D.
core   +2 more sources

Terrestrial and fluvial carbon fluxes in a tropical watershed: Nyong basin, Cameroon [PDF]

, 2009
The Nyong watershed, with an area of 27 800 km2 and a mean annual discharge of 390 m3 s−1, is the second largest river in Cameroon. The Nyong watershed serves as an outstanding study area for the examination of carbon fluxes in humid tropical ...
Boeglin, Jean-Loup, Brunet, Frédéric, Dubois, Krystel, Ndam-Ngoupayou, Jules-Rémy, Nkoue Ndondo, Gustave Raoul, Probst, Jean-Luc, Veizer, Jan   +6 more
core   +2 more sources

The (Glg)ABCs of cyanobacteria: modelling of glycogen synthesis and functional divergence of glycogen synthases in Synechocystis sp. PCC 6803

FEBS Letters, EarlyView.
We reconstituted Synechocystis glycogen synthesis in vitro from purified enzymes and showed that two GlgA isoenzymes produce glycogen with different architectures: GlgA1 yields denser, highly branched glycogen, whereas GlgA2 synthesizes longer, less‐branched chains.
Kenric Lee, Dimitrios Bekiari, Sofia Doello, Karl Forchhammer   +3 more
wiley   +1 more source

Chemical Speciation and Characterization of Trace Metals in Dry Camellia sinensis and Herbal Tea Marketed in Nigeria

Journal of Health and Pollution, 2018
Background. Trace metals from anthropogenic activities have been found to occur in tea brands and pose potential human health risks to consumers. Objectives.
Omowunmi H. Fred-Ahmadu, Adebusayo E. Adedapo, Mary O. Oloyede, Nsikak U. Benson   +3 more
doaj   +1 more source

Extraction Behaviors of Lignin and Hemicellulose-Derived Sugars During Organosolv Fractionation of Agricultural Residues Using a Bench-Scale Ball Milling Reactor

Energies, 2020
Ethanol organosolv fractionation combined with ball milling was conducted on three major agricultural residues: Rice husk (RH), rice straw (RS), and barley straw (BS).
Tae Hoon Kim, Hyun Kwak, Tae Hyun Kim, Kyeong Keun Oh   +3 more
doaj   +1 more source

Fractionation of Irradiated Cholesterol: Chemical Observations.

Experimental Biology and Medicine, 1926
One of us recently reported1 that cholesterol, as a result of exposure in air to light from the mercury-vapor quartz lamp, reacted differently from the untreated cholesterol towards a reagent consisting of aniline and concentrated hydrochloric acid. With the aid of this color reaction, fractionation of irradiated cholesterol was undertaken.
M. J. Shear, B. Kramer
openaire   +1 more source

DNC/HNC Ratio of Massive Clumps in Early Evolutionary Stages of High-Mass Star Formation

, 2012
We have observed the HN13C J=1-0 and DNC J=1-0 lines toward 18 massive clumps, including infrared dark clouds (IRDCs) and high-mass protostellar objects (HMPOs), by using the Nobeyama Radio Observatory 45 m telescope.
Aikawa, Aikawa, Benson, Beuther, Beuther, Caselli, Chambers, Crapsi, Devine, Egan, Hirota, Hirota, Jackson, Jijina, Kenji Furuya, Kurayama, Nakajima, Nami Sakai, Perault, Peters, Ragan, Rathborne, Rodgers, Sakai, Sakai, Satoshi Yamamoto, Simon, Sridharan, Sridharan, Takeshi Sakai, Tatematsu, Tomoya Hirota, Umebayashi, Walmsley, Yuri Aikawa   +34 more
core   +1 more source

Extreme enrichment in atmospheric 15N15N. [PDF]

, 2017
Molecular nitrogen (N2) comprises three-quarters of Earth's atmosphere and significant portions of other planetary atmospheres. We report a 19 per mil (‰) excess of 15N15N in air relative to a random distribution of nitrogen isotopes, an enrichment that ...
Fischer, Tobias P, Haslun, Joshua A, Hu, Huanting, Kohl, Issaku E, Li, Shuning, Ostrom, Nathaniel E, Schauble, Edwin A, Yeung, Laurence Y, Young, Edward D   +8 more
core   +1 more source

Structural biology of ferritin nanocages

FEBS Letters, EarlyView.
Ferritin is a conserved iron‐storage protein that sequesters iron as a ferric mineral core within a nanocage, protecting cells from oxidative damage and maintaining iron homeostasis. This review discusses ferritin biology, structure, and function, and highlights recent cryo‐EM studies revealing mechanisms of ferritinophagy, cellular iron uptake, and ...
Eloise Mastrangelo, Flavio Di Pisa
wiley   +1 more source

Physico-chemical characterisation of petroleum fractions

CT&F - Ciencia, Tecnología y Futuro, 1995
A complete physicochemical charaterization of several crude oil fractions is accomplished and nuclear magnetic resonance of 13C and 1H, column chromatography, mass spectrometry and empiric correlations  are used to establish their chemical composition.
C. A. BALDRICH, L. A. NOVOA, J. R. MARTÍNEZ, D. MOLINA   +3 more
openaire   +1 more source