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Photothermal materials for efficient solar powered steam generation
Solar powered steam generation is an emerging area in the field of energy harvest and sustainable technologies. The nano-structured photothermal materials are able to harvest energy from the full solar spectrum and convert it to heat with high efficiency. Moreover, the materials and structures for heat management as well as the mass transportation are also brought to the forefront. Several groups have reported their materials and structures as solutions for high performance devices, a few creatively coupled other physical fields with solar energy to achieve even better results. This paper provides a systematic review on the recent developments in photothermal nanomaterial discovery, material selection, structural design and mass/heat management, as well as their applications in seawater desalination and fresh water production from waste water with free solar energy. It also discusses current technical challenges and likely future developments. This article will help to stimulate novel ideas and new designs for the photothermal materials, towards efficient, low cost practical solar-driven clean water production
Reflections on the Arts, Environment, and Culture After Ten Years of The Goose
To mark the tenth anniversary of The Goose, we asked prominent ecologically-minded scholars, writers, artists, and educators from across Canada to reflect on the relationship between the arts, culture, and the environment. Their comments illuminate a wide range of triumphs and tensions, from the politics and practices of environmentalist writing and art, to the connections between the environment and matters of diversity and justice, to the past and future of ALECC (Association for Literature, Environment, and Culture in Canada), to the world of a single poem
A Link to the Past: Using Markov Chain Monte Carlo Fitting to Constrain Fundamental Parameters of High-Redshift Galaxies
We have a developed a new method for fitting spectral energy distributions
(SEDs) to identify and constrain the physical properties of high-redshift (4 <
z < 8) galaxies. Our approach uses an implementation of Bayesian based Markov
Chain Monte Carlo (PiMC^2) that allows us to compare observations to
arbitrarily complex models and to compute 95% credible intervals that provide
robust constraints for the model parameters. The work is presented in 2
sections. In the first, we test PiMC^2 using simulated SEDs to not only confirm
the recovery of the known inputs but to assess the limitations of the method
and identify potential hazards of SED fitting when applied specifically to high
redshift (z>4) galaxies. Our tests reveal five critical results: 1) the ability
to confidently constrain metallicity, population ages, and Av all require
photometric accuracy better than what is currently achievable (i.e. less than a
few percent); 2) the ability to confidently constrain stellar masses (within a
factor of two) can be achieved without the need for high-precision photometry;
3) the addition of IRAC photometry does not guarantee that tighter constraints
of the stellar masses and ages can be defined; 4) different assumptions about
the star formation history can lead to significant biases in mass and age
estimates; and 5) we are able to constrain stellar age and Av of objects that
are both young and relatively dust free. In the second part of the paper we
apply PiMC^2 to 17 4<z<8 objects, including the GRAPES Ly alpha sample (4<z<6),
supplemented by HST/WFC3 near-IR observations, and several broad band selected
z>6 galaxies. Using PiMC^2, we are able to constrain the stellar mass of these
objects and in some cases their stellar age and find no evidence that any of
these sources formed at a redshift much larger than z_f=8, a time when the
Universe was ~ 0.6 Gyr old.Comment: Submitted to ApJ (Full abstract, 47 pages, 17 figures, 7 tables
Chlorido(4,4′,4′′-tri-tert-butyl-2,2′:6′,2′′-terpyridine)platinum(II) chloride toluene monosolvate
In the title compound, [PtCl(C27H35N3)]Cl·C7H8, the PtII atom is coordinated in a pseudo-square-planar fashion by the N atoms of a 4,4′,4′′-tri-tert-butyl-2,2′:6′,2′′-terpyridine (tbtrpy) ligand and a Cl atom. The Pt—N distance of the N atom on the central pyridine is 1.941 (4) Å, while the peripheral N atoms have Pt—N distances of 2.015 (4) and 2.013 (4) Å. The Pt—Cl bond distance is 2.3070 (10) Å. The cations pack as dimers in a head-to-tail orientation with an intermolecular Pt⋯Pt distance of 3.2774 (3) Å and Pt⋯N distances of 3.599 (4), 3.791 (4) and 4.115 (4) Å. The solvent molecule is disordered and occupies two positions with a ratio of 0.553 (6):0.447 (6)
Chlorido(4,4′,4′′-tri-tert-butyl-2,2′:6′,2′′-terpyridine)platinum(II) tetrafluoridoborate
In the title compound, [PtCl(C27H35N3)]BF4, the PtII atom is in a pseudo-square-planar coordination, which is typical of Pt–terpyridine complexes. The Pt—Cl bond distance is 2.2998 (7) Å. The Pt—N distance of the N atom on the central pyridine is 1.931 (2) Å, while the peripheral N atoms have Pt—N distances of 2.018 (2) and 2.022 (2) Å. The cations pack as dimers in a head-to-tail orientation with an intermolecular Pt⋯Pt distance of 3.5214 (2) Å and Pt⋯N distances of 3.527 (2), 3.873 (2) and 4.532 (2) Å. In the crystal, cations and anions are linked by weak C—H⋯F hydrogen-bonding interactions
A Link to the Past: Using Markov Chain Monte Carlo Fitting to Constrain Fundamental Parameters of High-Redshift Galaxies
We have a developed a new method for fitting spectral energy distributions
(SEDs) to identify and constrain the physical properties of high-redshift (4 <
z < 8) galaxies. Our approach uses an implementation of Bayesian based Markov
Chain Monte Carlo (PiMC^2) that allows us to compare observations to
arbitrarily complex models and to compute 95% credible intervals that provide
robust constraints for the model parameters. The work is presented in 2
sections. In the first, we test PiMC^2 using simulated SEDs to not only confirm
the recovery of the known inputs but to assess the limitations of the method
and identify potential hazards of SED fitting when applied specifically to high
redshift (z>4) galaxies. Our tests reveal five critical results: 1) the ability
to confidently constrain metallicity, population ages, and Av all require
photometric accuracy better than what is currently achievable (i.e. less than a
few percent); 2) the ability to confidently constrain stellar masses (within a
factor of two) can be achieved without the need for high-precision photometry;
3) the addition of IRAC photometry does not guarantee that tighter constraints
of the stellar masses and ages can be defined; 4) different assumptions about
the star formation history can lead to significant biases in mass and age
estimates; and 5) we are able to constrain stellar age and Av of objects that
are both young and relatively dust free. In the second part of the paper we
apply PiMC^2 to 17 4<z<8 objects, including the GRAPES Ly alpha sample (4<z<6),
supplemented by HST/WFC3 near-IR observations, and several broad band selected
z>6 galaxies. Using PiMC^2, we are able to constrain the stellar mass of these
objects and in some cases their stellar age and find no evidence that any of
these sources formed at a redshift much larger than z_f=8, a time when the
Universe was ~ 0.6 Gyr old.Comment: Submitted to ApJ (Full abstract, 47 pages, 17 figures, 7 tables
Genome Sequence of Stenotrophomonas maltophilia PML168, Which Displays Baeyer-Villiger Monooxygenase Activity
Stenotrophomonas maltophilia PML168 was isolated from Wembury Beach on the English Coast from a rock pool following growth and selection on agar plates. Here we present the permanent draft genome sequence, which has allowed prediction of function for several genes encoding enzymes relevant to industrial biotechnology, including a novel flavoprotein monooxygenase
Phase transitions and the internal noise structure of nonlinear Schr\"odi nger equation solitons
We predict phase-transitions in the quantum noise characteristics of systems
described by the quantum nonlinear Schr\"odinger equation, showing them to be
related to the solitonic field transition at half the fundamental soliton
amplitude. These phase-transitions are robust with respect to Raman noise and
scattering losses. We also describe the rich internal quantum noise structure
of the solitonic fields in the vicinity of the phase-transition. For optical
coherent quantum solitons, this leads to the prediction that eliminating the
peak side-band noise due to the electronic nonlinearity of silica fiber by
spectral filtering leads to the optimal photon-number noise reduction of a
fundamental soliton.Comment: 10 pages, 5 figure
Linking Life Skills and Norms with adolescent substance use and delinquency in South Africa
We examined factors targeted in two popular prevention approaches with adolescent drug use and
delinquency in South Africa. We hypothesized adolescent life skills to be inversely related, and
perceived norms to be directly related to later drug use and delinquency. Multiple regression and a
relative weights approach were conducted for each outcome using a sample of 714 South African
adolescents ages 15 to 19 years (M = 15.8 years, 57% female). Perceived norms predicted gateway
drug use. Conflict resolution skills (inversely) and perceived peer acceptability (directly) predicted
harder drug use and delinquency. The “culture of violence” within some South African schools
may make conflict resolution skills more salient for preventing harder drug use and delinquency.Department of HE and Training approved lis
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