The aim of this book is to provide an overview on the importance of stoichiometry in the materials science field. It presents a collection of selected research articles and reviews providing up-to-date information related to stoichiometry at various levels. Being materials science an interdisciplinary area, the book has been divided in multiple sections, each for a specific field of applications. The first two sections introduce the role of stoichiometry in nanotechnology and defect chemistry, providing examples of state-of-the-art technologies. ...
Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Phonon Raman spectra of colloidal CdTe nanocrystals: effect of size, non-stoichiometry and ligand exchange
Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học 'Respiratory Research cung cấp cho các bạn kiến thức về ngành y đề tài: Biophysical analysis of HTLV-1 particles reveals novel insights into particle morphology and Gag stoichiometry...
We studied the interaction of several metal ions with the
copper chaperone fromEnterococcus hirae(EhCopZ). We
show that the stoichiometry of the protein–metal complex
varies with the experimental conditions used. At high con-centration of the protein in a noncoordinatingbuffer, a
dimer, (EhCopZ)2–metal, was formed. The presence of a
potentially coordinatingmolecule L in the solution leads to
the formation of a monomeric ternary complex, EhCopZ–
Cu–L, where L can be a buffer or a coordinatingmole-cule (glutathione, tris(2-carboxyethyl)phosphine). ...
-dependent F-ATP synthases ofIlyobacter tartaricusandPropioni-genium modestum contain membrane-embedded ring-shaped c subunit
assemblies with a stoichiometry of 11. Subunit c from either organism was
overexpressed in Escherichia coliusing a plasmid containing the corres-ponding gene, extracted from the membrane using detergent and then puri-fied.
Today, ozone is considered as an alternative oxidant-disinfectant agent with multiple
possibilities of application in water, air pollution, medicine, etc. Particularly, in water
treatment it has many abilities to disinfect, oxidize, or to be combined with other
technologies and reagents.
Tribasic lead sulfate Ž3BS. and tetrabasic lead sulfate Ž4BS., used as precursors of the positive active material in the leadracid batteries, were prepared by a new method: reactive grinding. The effects of various experimental parameters Žstoichiometry, hygrometry of the starting compounds, duration of mechanical treatment. upon the nature and morphological features of the resulting phase were investigated.
Science seeks to understand and explain our world, be that its physical composition
(geology), chemical composition (chemistry), the way its composite matter interacts
(physics), or the organisms that inhabit it (biology). We can only get an idea of what
life is all about by piecing together information from each discipline to give us the big
We don’t have to look very far to realize that it is difficult, if not impossible, to
separate biology from chemistry. After all, our body is a bag of chemicals.
Research on ion channels has exploded in the last few decades and it is now
clear that ion channels play essential roles in cell biology and physiology, with
their dysfunction being the root cause of many human diseases. Understanding
human biology in the post-genome sequencing era requires that the function of
the protein products encoded by these recently sequenced genes be quantified.
Science and engineering have dominated world events and world culture for at least
150 years. The blind and near blind have been made to see. The deaf and near deaf have
been made to hear. The ill have been made well. The weak have been made strong.
Radio, television and the internet have made the world seem smaller. And some of us
have left the planet. Computers have played an essential role in all of these
developments; they are now ubiquitous. These miraculous events happened by design—
not by accident. Individuals and teams set out to accomplish goals.
many metals form complex with a ligand:
Cu++ + NH3 ⇔ Cu(NH3)++ Cu(NH3)2+ + NH3 ⇔ Cu (NH3)22+ Cu (NH3)22+ + NH3 ⇔ Cu (NH3)32+ Cu (NH3)32+ + NH3 ⇔ Cu (NH3)42+ Kf1 Kf2 Kf3 Kf4
Zn (NH3) complexes vs lg NH3
.• theoretically could titrate Zn with ammonia • stepwise Kf very similar • difficult to know stoichiometry • to ensure all one form, need excess NH3 • titration never gives good equivalence point • can’t use monodentate ligand to titrate metals
Titrations with EDTA
• • • • use multidentate ligands e.g.
Transport of presecretory proteins into the mammalian
rough endoplasmic reticulum involves a protein translocase
that comprises the integral membrane proteins Sec61ap,
Sec61bp, and Sec61cp as core components. Electron
microscopic analysis of protein translocase in rough micro-somal membranes suggested that between three and four
heterotrimeric Sec61p complexes form the central unit of
Kinetics is the study of how fast chemical reactions occur. There are 4 important factors which affect rates of reactions: Reactant concentration, temperature, action of catalysts, and surface area. Invite you to consult.
Transthyretin is a tetrameric binding protein involved in the transport of
thyroid hormones and in the cotransport of retinol by forming a complex
in plasma with retinol-binding protein. In the present study, we report the
crystal structure of a macromolecular complex, in which human transthy-retin, human holo-retinol-binding protein and a murine anti-retinol-binding
protein Fab are assembled according to a 1 : 2 : 2 stoichiometry.
In dense plant populations, individuals shade each other resulting in a low-light habitat that is enriched in far-red light. This light quality gradient
decreases the efficiency of the photosynthetic light reaction as a result of
imbalanced excitation of the two photosystems. Plants counteract such con-ditions by performing acclimation reactions.
The cellular level of the organic osmolyte taurine is abalance
betweenactiveuptakeandpassive leakviaavolume sensitive
pathway. Here, we demonstrate that NIH3T3 mouse fibro-blasts express a saturable, high affinity taurine transporter
(TauT,Km¼18lM), and that taurine uptake via TauT is
-dependent process with an apparent
2.5 : 1 : 1 Na
/taurine stoichiometry. Transport activ-ity is reduced following acute administration of H2O2 or
We report on the results obtained by measuring the stoi-chiometry of antenna polypeptides in Photosystem I (PSI)
fromArabidopsis thaliana. This analysis was performed by
quantification of Coomassie blue binding to individual
LHCI polypeptides, fractionation by SDS/PAGE, and by
the use of recombinant light harvesting complex of Photo-system I (Lhca) holoproteins as a standard reference. Our
results show that a single copy of each Lhca1–4 polypeptide
is present in Photosystem I.
With the aim of extending our knowledge on the reaction
pathways of Zn-metallothionein (MT) and apo-MT species
in the presence of Hg(II), we monitored the titration of
-aMT and Zn3
-bMT proteins, at pH 7 and 3,
with either HgCl2or Hg(ClO4
by CD and UV-vis spectr-oscopy.
One-electron oxidation of six different c-type lysozymes
from hen egg white, turkey egg white, human milk, horse
milk, camel stomach and tortoise was studied by gamma-and pulse-radiolysis.In the first step, one tryptophan side
chain is oxidized to indolyl free radical, which is produced
quantitatively.As shown already, the indolyl radical subse-quently oxidizes a tyrosine side chain to the phenoxy radical
in an intramolecular reaction.However this reaction is not
total and its stoichiometry depends on the protein.