2,892 research outputs found
Synchronous liver metastases, oncosurgical strategy: How to resect the unresectable?
info:eu-repo/semantics/publishedVersio
Review of \u3ci\u3eVanished\u3c/i\u3e: \u3ci\u3eThe Sixty-Year Search for the Missing Men of World War II\u3c/i\u3e
Review of Vanished: The Sixty-Year Search for the Missing Men of World War II by Wil S. Hylton. 2013. Riverhead Books, New York. xiii + pp. 239. $27.95 (cloth), ISBN 978-1-59448-727-9. Reviewed by Mack Cristino, University of Nebraska-Lincoln.
Scannon’s mission approach was one of social and expert collaboration. Scannon valued the stories, memories, and accounts of the indigenous Palauan peoples and the families of the missing crew. He also sat down to interview and visit fellow Long Ranger veterans of the 307th Bombardment group. Scannon goes on to share that these accounts were invaluable to the search for the missing men. The heartfelt pleas from their loved ones and comrades touched the heart of Scannon and were heard far and wide by the many experts who soon also devoted themselves to the search. Hylton describes Scannon’s recruitment of scientists, archaeologists, and divers to his fulfilling project. These collaborations formed the heart of this book
Review of \u3ci\u3eStill Life with Bones\u3c/i\u3e: \u3ci\u3eGenocide, Forensics, and What Remains\u3c/i\u3e
Review of Still Life with Bones: Genocide, Forensics, and What Remains by Alexa Hagerty. 2023. Crown Publishing Group, New York. xvi + pp. 228. $28.00 (cloth), ISBN 978-0-593-44313-2. Review by: Mack Cristino, University of Nebraska-Lincoln.
Alexa Hagerty pours her entire heart into this book in both recounting her own personal experiences and passions in contributing to the repatriation of these victims and in bringing about awareness of such governmental corruption. Millions of innocent people are dead at the hands of greedy figureheads, and it is in the marriage of forensics and empathy that we will solve these crimes and bring these people back to their families. Hagerty’s work pleads for the continued growth of empathetic attitudes and a sense of humanity in the forensic sciences
Photoelectrochemical hydrogen production from aqueous solution employing nanostructured semiconductors
The focus of this thesis is the exploitation of various types of photoelectrodes based on
nanostructured materials to be employed in photoassisted electrolysis schemes, aimed to
convert solar energy into chemical energy.
Since the world demand of energy is projected to increase in the next years,
environmental issues like global warming and climate change impose a change in our
way of producing and storing energy, currently and mainly based on the combustion of
fossil fuels. Both a stable improvement of the quality of life for an increasing world
population and the preservation the environment will require the use of progressively
larger amounts of new energy sources which must be carbon neutral, renewable and
low cost. This defines a grand scientific and technological challenge for the XXI
century.
Sunlight provides by far the largest of all carbon-neutral energy sources. More energy
from sunlight strikes the Earth in one hour (4.3 x 1020 ) than all the energy consumed on
the planet in a year (4.1 x 1020 J). Yet solar electricity provides only approximately 1
millionth of the total electricity supply, and renewable biomass provides less than 0.1%
of the total energy consumed. There is a huge gap between our present use of solar
energy and its enormous undeveloped potential.
Hydrogen production from solar water splitting is regarded by many as the “holy grail”
of photochemistry, providing a practically inexhaustible fuel source and, since the
experiment of Fujishima and Honda, the use of semiconductor photoelectrodes capable
of operating with a virtually unitary quantum yield has appeared as a convenient mean
to realize water splitting in a photoelectrochemical cell.
In particular, a large part of this thesis work has been devoted to the development of
efficient WO3 photoelectrodes which is a promising material for water splitting,
coupling favourable energetics for oxygen evolution, high photochemical stability in
aqueous media and visible photon absorption up to 500 nm. .
At first, different synthetic approaches for obtaining nanostructured WO3 on transparent
conductive oxides have been explored by keeping the Santato-Augustynski recipe as a
main guideline. In general the preparation of nanostructured photoelectrodes involves
the formation of stabilized H2WO4 colloidal precursors in the presence of different
organic dispersing agents which control both nanoparticle size and film porosity. The
relationships between crystallite size, film porosity, electrochemically active surface
and photoelectrochemical behavior under simulated solar illumination have been
studied.
The work has then focused on the preparation of WO3 films by potentiostatic
anodization of metallic tungsten in different solvent/electrolyte compositions with the
aim of improving the charge transfer and charge transport kinetics by creating tightly
interconnected porous oxide structures directly bound to a metal collector. In the
NMF/H2O/NH4F solvent mixture the anodization leads to highly efficient WO3
photoanodes, which, combining spectral sensitivity, high electrochemically active
surface and improved charge transfer kinetics, outperform, under simulated solar
illumination, most of the reported nanocrystalline substrates produced by anodization
in aqueous electrolytes and by sol gel methods. The use of such electrodes results in
high water electrolysis yield, of the order of 70% in 1 M H2SO4 under a potential bias of
1 V vs SCE and close to 100% in the presence of methanol acting as a hole scavenger.
The requirement to harvest large part of the solar spectrum and photooxidize small
molecules like H2S (largely present as a contaminant of hydrocarbon sources) has led
us to the study of heterointerfaces between TiO2 and group VI semiconductors like
CdS, CdSe, CdTe and Bi2S3, which are characterized by a relatively narrow band gap
(from 2.4 eV for CdS to 1.4 eV for Bi2S3).
The use of colloidal and nanotubular TiO2 as a substrate for growing sensitizing
semiconductors by chemical and electrochemical means was instrumental in reducing
significantly degradative self photoxidation and recombination leading to good photon
to electron quantum yields, ranging from 20% (Bi2S3) to 60% (CdS)
The photoelectrochemical behavior of TiO2 photoanodes sensitized by water stable
molecular Ru(II) dyes was finally explored in the context of photoinduced hydrogen
generation. The photoanodes sustained 240 h of irradiation without undergoing
appreciable hydrolysis and decomposition in an aqueous environment at pH 3. Despite a
favourable driving force for direct water oxidation, the performances in pure water were
far from an applicative interest. However, the use of organic sacrificial donors, like
isoprapanol and ascorbic acid considerably enhanced their photoanodic response and,
interestingly, the exploitation of iodide, a well known electron donor in
photoelectrchemical cells, was more problematic because the adsorption of
photogenerated I3
- from aqueous media favored charge recombination with conduction
band electrons, thus limiting the efficiency of the photoelectrosynthetic device.
However, experiments performed in a three-compartment cell, where the photolectrode
was in contact with an organic solvent preventing triiodide adsorption, revealed a
remarkable photocurrent, with an electrolysis yield close to 87%.
Although the problem of finding the ideal system for photoassisted electrolysis has not
been entirely solved, this thesis work suggests some feasible approaches for obtaining
high photon to electron conversion efficiencies, pointing out that the basis of an
efficient photoelectrochemical system reside in the combination of an high
electroactive area with fast interfacial charge transfer kinetics, necessary to overcome
losses arising from recombination.
II
Cristino Bernazard to Mr. Congressman, 20 January 1978
Copy typed letter signed dated 20 January 1978 from Cristino Bernazard, Secretary of the Puerto Rican House of Representatives, to Mr. Congressman, re: resolution upon death of Humphrey.https://egrove.olemiss.edu/joecorr_e/1002/thumbnail.jp
Estructuras sedimentarias primarias
Depto. de Geodinámica, EstratigrafĂa y PaleontologĂaFac. de Ciencias GeolĂłgicasTRUEpu
Bosquejo estratigráfico de la región de El Tranco Pontones-Santiago de la Espada (Zona prebética, provincia de Jaén
Some results obtained in the El Tranco-Santiago de la Espada area, located in the Sierras de Cazorla y
Segura (Prebetic Zone), are shown in this note.
The established series are described and related the one the other. Several importants lacunas and the presence of an
intramiocene unconformity are pointed out. A geological scheme are included
PresentaciĂłn de "PaleogeografĂa de la Meseta Norte durante el Terciario"
Depto. de Geodinámica, EstratigrafĂa y PaleontologĂaFac. de Ciencias GeolĂłgicasTRUEpu
Ambientes sedimentarios y facies
Depto. de Geodinámica, EstratigrafĂa y PaleontologĂaFac. de Ciencias GeolĂłgicasTRUEpu
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