264 research outputs found
Historic Scour Data Collected at Selected Bridges in South Carolina
2008 S.C. Water Resources Conference - Addressing Water Challenges Facing the State and Regio
An inverted-sandwich diuranium μ-η5:η5-cyclo-P5 complex supported by U-P5 δ-bonding
Reaction of [U(TrenTIPS)] [1, TrenTIPS=N(CH2CH2NSiiPr3)3] with 0.25 equivalents of P4 reproducibly affords the unprecedented actinide inverted sandwich cyclo-P5 complex [{U(TrenTIPS)}2(μ-η5:η5-cyclo-P5)] (2). All prior examples of cyclo-P5 are stabilized by d-block metals, so 2 shows that cyclo-P5 does not require d-block ions to be prepared. Although cyclo-P5 is isolobal to cyclopentadienyl, which usually bonds to metals via σ- and π-interactions with minimal δ-bonding, theoretical calculations suggest the principal bonding in the U(P5)U unit is polarized δ-bonding. Surprisingly, the characterization data are overall consistent with charge transfer from uranium to the cyclo-P5 unit to give a cyclo-P5 charge state that approximates to a dianionic formulation. This is ascribed to the larger size and superior acceptor character of cyclo-P5 compared to cyclopentadienyl, the strongly reducing nature of uranium(III), and the availability of uranium δ-symmetry 5f orbitals
Development of a Mercury Load Model for McTier Creek, South Carolina Using TOPMODEL
2012 S.C. Water Resources Conference - Exploring Opportunities for Collaborative Water Research, Policy and Managemen
Isolation of elusive HAsAsH in a crystalline diuranium(IV) complex
The HAsAsH molecule has hitherto only been proposed tentatively as a short-lived species generated in electrochemical or microwave-plasma experiments. After two centuries of inconclusive or disproven claims of HAsAsH formation in the condensed phase, we report the isolation and structural authentication of HAsAsH in the diuranium(IV) complex [{U(TrenTIPS)}2(μ-η2:η2-As2H2)] (3, TrenTIPS=N(CH2CH2NSiPri3)3; Pri=CH(CH3)2). Complex 3 was prepared by deprotonation and oxidative homocoupling of an arsenide precursor. Characterization and computational data are consistent with back-bonding-type interactions from uranium to the HAsAsH π*-orbital. This experimentally confirms the theoretically predicted excellent π-acceptor character of HAsAsH, and is tantamount to full reduction to the diarsane-1,2-diide form
Melioidosis in Birds and Burkholderia pseudomallei Dispersal, Australia
To the Editor: Melioidosis is an emerging infectious disease of humans and animals caused by the gram-negative bacterium Burkholderia pseudomallei, which inhabits soil and surface water in the disease-endemic regions of Southeast Asia and northern Australia (1). The aim of this study was to assess the potential for birds to spread B. pseudomallei. Birds are known carriers of various human pathogens, including influenza viruses, West Nile virus, Campylobacter jejuni, and antimicrobial drug–resistant Escherichia coli (2)
Exercise attenuates cardiotoxicity of anthracycline chemotherapy measured by global longitudinal strain [Letter]
[Extract] Anthracycline-based chemotherapy (AC) is a common
treatment for patients with breast cancer and has
been associated with a dramatic improvement in
breast cancer survivorship. Among patients with
early-stage breast cancer, cardiovascular diseases
represent the most common cause of mortality, and
there is a growing emphasis on strategies for minimizing
the toxic effects of breast cancer treatments
on the cardiovascular system (1)
Exercise attenuates cardiotoxicity of anthracycline chemotherapy measured by global longitudinal strain [Letter]
[Extract] Anthracycline-based chemotherapy (AC) is a common
treatment for patients with breast cancer and has
been associated with a dramatic improvement in
breast cancer survivorship. Among patients with
early-stage breast cancer, cardiovascular diseases
represent the most common cause of mortality, and
there is a growing emphasis on strategies for minimizing
the toxic effects of breast cancer treatments
on the cardiovascular system (1)
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