Studies in the coordination chemistry of phospholes

The chemical, physicochemical, theoretical and metal coordination studies of phospholes which have so far appeared in the literature are reviewed briefly with particular reference to the electronic structure of the system. The coordinating properties of the simple phospholes 1-phenylphosphole (PP), 3-methyl-1-phenylphosphole (mPP), 3,4- dimethyl-l-phenylphosphole (dPP) and 3,4-dimethyl-1-rwbutylphosphole (dBP) with the metal ions Re(III), Ru(III), Ru(II), Co{II), Rh(III), Ir(III), Ni(II), Pd(II), Pt(II), Cu(I) and Hg(II) and also with carbonyl complexes of Ru(II) and Rh(I) have been studied. ... Differences in the behavior of the various phospholes studied here, and also other phospholes, in complex formation are attributed to variations in the substitution pattern with the type of substitution at the phosphorus atom being apparently of particular importance. The results are discussed in terms of orbital perturbation of a pyramidal phosphole in which the HOMO may not be the lone-pair orbital and also in terms of a pyramidal but aromatic phosphole system

Temporal trends and patterns of infective endocarditis in a Chinese population:A territory-wide study in Hong Kong (2002-2019)

BACKGROUND: The characteristics of infective endocarditis (IE) in Asians are poorly understood. Therefore, we aim to describe the epidemiological trends and clinical features of IE in Hong Kong. METHODS: All patients with incident IE from 2002–2019 in a territory-wide clinical database in Hong Kong were identified. We studied the age- and sex-adjusted and one-year mortality of IE between 2002 and 2019 and identified significant contributors to 1-year all-cause death using the attributable fraction. We used propensity score and inverse propensity of treatment weighting to study the association of surgery with mortality. FINDINGS: A total of 5139 patients (60.4 ± 18.2years, 37% women) were included. The overall incidence of IE was 4.9 per 100,000 person-year, which did not change over time (P = 0.17). Patients in 2019 were older and more comorbid than those in 2002. The one-year crude mortality rate was 30% in 2002, which did not change significantly over time (P = 0.10). Between 2002 and 2019, the rate of surgery increased and was associated with a 51% risk reduction in 1-year all-cause mortality (Hazard Ratio 0.49 [0.28–0.87], P = 0.015). Advanced age (attributable fraction 19%) and comorbidities (attributable fraction 15%) were significant contributors to death. INTERPRETATION: The incidence of IE in Hong Kong did not change between 2002 and 2019. Patients with IE in 2019 were older and had more comorbidities than those in 2002. Mortality of IE remains persistently high in Hong Kong. Together, these data can guide public health strategies to improve the outcomes of patients with IE. FUNDING: This work was supported by Sanming Project of Medicine in Shenzhen, China [No. SZSM201911020] and HKU-SZH Fund for Shenzhen Key Medical Discipline [No. SZXK2020081]

Design and synthesis of some polyaminopolycarboxylic acids and the structural influence of their anions on the separation of actinides and lanthanides

Investigation of some methods for the preparation of four polyaminopolycarboxylic acids: thiobis(ethylenenitrilo)-N,N,N',N'-tetraacetic acid, N,N-bis(2-aminoethyl)aniline-N',N',N'',N''-tetraacetic acid, bis(3-aminopropyl)ether-N,N,N',N'-tetraacetic acid and N,N-bisN',N'-dicarboxymethyl-3-aminopropyl-N-methylammonioacetate are reported. The coordinating properties of their anions with regard to lanthanide ions have been examined;Polyaminopolycarboxylates form 1:1 chelate species with trivalent lanthanide ions in aqueous media. The stability constants of their metal chelate species depend upon the size of the chelating rings formed, the basicity of the middle atom in the chain, and the number of coordination points between anion and metal cation;Tracer level ('241)Am-('155)Eu cation-exchange experiments explore how the relative magnitude of the chelate stability constants affects the separation of members of the lanthanide and actinide series; *DOE Report IS-T-1046. This work was performed under Contract No. W-7405-Eng-82 with the U.S. Department of Energy.</p

The light metals industry of China /

Includes bibliographical references (p. 36).Mode of access: Internet

Modeling of aqueous and organic phase speciation for solvent extraction systems

The TRUEX (TRansUranic EXtraction) solvent extraction process has the ability to remove, separate, and recover transuranic (TRU) elements from acidic nuclear waste solutions. A computer model of the TRUEX process is currently being developed for use in flowsheet design and process optimization. The correlations that are to be used in the model for generating extraction distribution ratios are based on chemical mass action principles and require calculation of aqueous and organic phase speciation. Aqueous phase activity coefficients are calculated using methods available in the literature, while the organic phase species are treated in terms of ideal associated solution theory. This approach is demonstrated for the extraction of HNO/sub 3/, HTcO/sub 4/, and americium nitrate by n-octyl(phenyl)-N,N-diisobutylcarbamoyl-methylphosphine oxide (CMPO)---the primary metal extractant in the TRUEX solvent. 23 refs., 5 figs

A Generic Bayesian Belief Model for Similar Cyber Crimes

Part 5: NETWORK FORENSICSInternational audienceBayesian belief network models designed for specific cyber crimes can be used to quickly collect and identify suspicious data that warrants further investigation. While Bayesian belief models tailored to individual cases exist, there has been no consideration of generalized case modeling. This paper examines the generalizability of two case-specific Bayesian belief networks for use in similar cases. Although the results are not conclusive, the changes in the degrees of belief support the hypothesis that generic Bayesian network models can enhance investigations of similar cyber crimes

Sensitivity Analysis of Bayesian Networks Used in Forensic Investigations

Part 5: ADVANCED FORENSIC TECHNIQUESInternational audienceResearch on using Bayesian networks to enhance digital forensic investigations has yet to evaluate the quality of the output of a Bayesian network. The evaluation can be performed by assessing the sensitivity of the posterior output of a forensic hypothesis to the input likelihood values of the digital evidence. This paper applies Bayesian sensitivity analysis techniques to a Bayesian network model for the well-known Yahoo! case. The analysis demonstrates that the conclusions drawn from Bayesian network models are statistically reliable and stable for small changes in evidence likelihood values