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Books > Professional & Technical > Technology: general issues
Gerrie Radlof se gewilde Oloff die Seerowerreeks is oorspronklik
tussen 1957 en 1961 uitgegee en het daarna reeds vier uitgawes
beleef. Die verhale, wat in die 1740's afspeel aan die Kaap de
Goede Hoop en die seewee daarom heen, is verwerk om aan te pas by
die moderne taalgebruik en aan te sluit by die hedendaagse tiener,
maar niks van die oorspronklike sjarme en spanning het in die
verwerking verlore gegaan nie. Ook geskik as leesstof vir Afrikaans
tweede taal vir ouer leerlinge.
A Best Book of 2020: The Washington Post * NPR * Chicago Tribune *
Smithsonian A "remarkable" (Los Angeles Times), "seductive" (The
Wall Street Journal) debut from the new cohost of Radiolab, Why
Fish Don't Exist is a dark and astonishing tale of love, chaos,
scientific obsession, and--possibly--even murder. "At one point,
Miller dives into the ocean into a school of fish...comes up for
air, and realizes she's in love. That's how I felt: Her book took
me to strange depths I never imagined, and I was smitten." --The
New York Times Book Review David Starr Jordan was a taxonomist, a
man possessed with bringing order to the natural world. In time, he
would be credited with discovering nearly a fifth of the fish known
to humans in his day. But the more of the hidden blueprint of life
he uncovered, the harder the universe seemed to try to thwart him.
His specimen collections were demolished by lightning, by fire, and
eventually by the 1906 San Francisco earthquake--which sent more
than a thousand discoveries, housed in fragile glass jars,
plummeting to the floor. In an instant, his life's work was
shattered. Many might have given up, given in to despair. But
Jordan? He surveyed the wreckage at his feet, found the first fish
that he recognized, and confidently began to rebuild his
collection. And this time, he introduced one clever innovation that
he believed would at last protect his work against the chaos of the
world. When NPR reporter Lulu Miller first heard this anecdote in
passing, she took Jordan for a fool--a cautionary tale in hubris,
or denial. But as her own life slowly unraveled, she began to
wonder about him. Perhaps instead he was a model for how to go on
when all seemed lost. What she would unearth about his life would
transform her understanding of history, morality, and the world
beneath her feet. Part biography, part memoir, part scientific
adventure, Why Fish Don't Exist is a wondrous fable about how to
persevere in a world where chaos will always prevail.
The conditions of our overpopulated planet with ever-growing energy
needs, fossil fuels in limited supplies, and inefficient energy use
world-wide, are creating a global crisis. Science has a
responsibility, as well as a grand opportunity, to solve these
energy-based problems of society. Science's new nanotechnologies,
and the creativity they bring, are particularly appropriate to
solve these problems. For example, energy-saving lighting, coupled
with improved harvesting and conversion of sunlight into electric
energy, will have a great impact on society's energy needs. Also,
development of energy efficient and low cost fuel cells, which
could eventually replace car engines, has a potential to improve
everyday life greatly. Nanomaterials offer an opportunity to
develop new low-cost materials as environmentally friendly
solutions and renewable energy sources, in order to meet society's
energy needs. Fortunately, a wide spectrum of the scientific
community has become interested in developing these nanomaterials
in order to solve the above energy challenges. Nanomaterials offer
unique mechanical, catalytic, electronic, and optical features,
which are different from those of the analogous bulk material (1).
This is because nanomaterials have scale-dependent properties, due
to quantum size effects, which means the nanomaterial size (10 -
100 nm) is smaller than the mean free path of their electrons.
Thus, nanomaterials have great promise for use in harvesting solar
energy, hydrogen production and storage, fuel cells, catalysis,
chemical, optical sensors, drug delivery systems (such as
liposomes), and nanothermite reactions (2-4). Fluorine-containing
nanomaterials generally have certain unique properties which are
often improved relative to the analogous non-fluorinated
nanomaterials, and which therefore could be engineered. Although
fluorine has the highest electronegativity of all the elements,
which means that bonds to fluorine are generally quite polar, it is
also in the second period of the periodic table, so it also has a
small atomic radius and forms strong bonds. This produces the
following properties, which also are characteristic of and bring
great advantages to fluorine nanomaterials: high thermal and
chemical stability, resistance to degradation by solvents, low
flammability, low moisture absorption, low surface tension or
energy, low dielectric constant, and serving as a strong oxidant
under high energy conditions (5). However, little attention has
been given to fluorine-containing organic and inorganic
nanomaterials, which are predicted to have these unusual
characteristics. This book presents examples of four diverse
classes of these nanomaterials.
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