12 research outputs found
Magnetic ground state of the two isostructual polymeric quantum magnets [Cu(HF2)(pyrazine)2]SbF6 and [Co(HF2)(pyrazine)2]SbF6 investigated with neutron powder diffraction
The magnetic ground state of two isostructural coordination polymers, (i) the quasi-two-dimensional S=1/2 square-lattice antiferromagnet [Cu(HF2)(pyrazine)2]SbF6 and (ii) a related compound [Co(HF2)(pyrazine)2]SbF6, was examined with neutron powder diffraction measurements. We find that the ordered moments of the Heisenberg S=1/2 Cu(II) ions in [Cu(HF2)(pyrazine)2]SbF6 are 0.6(1)μb, while the ordered moments for the Co(II) ions in [Co(HF2)(pyrazine)2]SbF6 are 3.02(6)μb. For Cu(II), this reduced moment indicates the presence of quantum fluctuations below the ordering temperature. We show from heat capacity and electron spin resonance measurements that due to the crystal electric field splitting of the S=3/2 Co(II) ions in [Co(HF2)(pyrazine)2]SbF6, this isostructual polymer also behaves as an effective spin-half magnet at low temperatures. The Co moments in [Co(HF2)(pyrazine)2]SbF6 show strong easy-axis anisotropy, neutron diffraction data, which do not support the presence of quantum fluctuations in the ground state, and heat capacity data, which are consistent with 2D or close to 3D spatial exchange anisotropy
Specialist hospital services Exploring public attitudes to travel and specialist treatment
SIGLEAvailable from British Library Document Supply Centre-DSC:7769.05354(33) / BLDSC - British Library Document Supply CentreGBUnited Kingdo
TĪNĒ: the fate, behavior, and ecotoxicology of manufactured nanomaterials in terrestrial ecosystems
We have developed a life cycle perspective
inspired conceptual model (CM) that indicates terrestrial ecosystems
as a major repository for ZnO, TiO2, and Ag manufactured nanomaterials
(MNMs) introduced via the land application of MNM-containing biosolids.
In this project we are investigating the transport, fate, behavior, bioavailability,
and effects of MNMs in(to) agroecosystems under environmentally
realistic scenarios organized around three key hypotheses: Hypothesis (H1) Surface chemistry is the primary factor influencing the fate and transport
of MNMs in the terrestrial environment as well as the bioavailability
and effects to biological receptors; Hypothesis (H2) Once released to the
environment, pristine MNM surfaces will be modified by interactions with
organic and inorganic ligands (macromolecules) or via other biogeochemical
transformations (aging effects forming a-MNMs); Hypothesis (H3)
Ecoreceptors will respond to interactions with pristine metal and metal
oxide MNMs, a-MNMs, and/or dissolved constituent metal ions and bulk
oxides by specific ecological and toxicogenomic responses that will reflect
their combined effects. The overall objectives are to: O1) Compare the
transport, fate, behavior, bioavailability, and effects of MNMs, a- MNMs,
and/or dissolved free metals/bulk oxides to organisms with key terrestrial
ecosystem functions, as well as exposure pathways involving humans; O2)
Determine MNM, surface modified MNM and a-MNM interactions with
important biological targets relevant to the BLM and pBRM models and
relate these interactions to physicochemical properties; O3) Validate models
with information generated from experiments designed to address O1 for
MNMs introduced through a pilot scale Waste Water Treatment Process
(WWTP) to key terrestrial ecoreceptors, including effects of MNMs on the
WWTP itself; O4) Determine realistic MNM emission scenarios for Tier
1 MNMs in wastewater from the WWT pilot plant data and develop first
generation Life-Cycle-Analysis-inspired Risk Assessment (LCA-RA) model
components for terrestrial effects of Tier 1 MNMs and a-MNMS based
on data generated in experiments designed to address O1, O2, & O3; and
O5) Provide tools for in situ detection, monitoring, and characterization of
pristine MNMs and a-MNMs in environmental media and biota. The key
results from aging and toxicity studies will be presented
A Review of Factors Influencing Whole-Body Vibration Injuries in Forestry Mobile Machine Operators
Mobile machine operators in the forestry industry are subjected to long hours of whole-body vibration exposure while adopting static seated postures and performing repeated hand and foot movements to operate controls. These conditions have been found to put operators at increased risk for musculo-skeletal injuries and pain in the neck, shoulders, and back, as well as decreased productivity. This paper provides a review of the individual risk factors for these musculoskeletal problems and explores the possible interactions between risk factors and their effects on injury and productivity. Gaps in the literature and directions for future research are identified and discussed