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The study of Total Dissolved Solids (TDS) and concentration distribution of multielements including toxic elements in river–wetland ecosystem at different locations of Satluj River and Harike Wetland were carried out to understand the mobilization behavior of elements including toxic elements. The concentrations of multi-elements in water and sediments were determined using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Instrumental Neutron Activation Analysis (INAA) utilizing reactor neutrons, respectively. The concentration values are found to be within permissible limit set by WHO and BIS. The concentration factors of selected common elements namely Cr, Mn, Fe, Zn and As were evaluated utilizing their corresponding concentrations in water and sediment samples.

The synthesis, structures, and magnetic properties of monomeric half-sandwich iron and cobalt imidazolin-2-iminato complexes have been comprehensively investigated. Salt metathesis reactions of [Cp'M(μ-I)]2 (1-M, M = Fe, Co; Cp' = η5-1,2,4-tri-tert-butylcyclopentadienyl) with [ImDippNLi]2 (ImDippN = 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-iminato) furnishes the terminal half-sandwich compounds [Cp'M(NImDipp)] (2-M, M = Fe, Co), which can be regarded as models for elusive half-sandwich iron and cobalt imido complexes. X-ray diffraction analysis confirmed the structure motif of a one-legged piano stool. Complex 2-Co can also be prepared by an acid-base reaction between [Cp'Co{N(SiMe3)2}] (3-Co) and ImDippNH. The electronic and magnetic properties of 2-M and 3-Co were probed by 57Fe Mossbauer spectroscopy (M = Fe), X-band EPR spectroscopy (M = Co), and solid-state magnetic susceptibility measurements. In particular, the central metal atom adopts a high-spin (S = 2) state in 2-Fe, while the cobalt complex 2-Co represents a rare example of a Co(II) species with a coordination number different from six displaying a low-spin to high-spin spin-crossover (SCO) behavior. The experimental observations are complemented by DFT calculations.

Uranium (U) is ubiquitously abundant in the environment. Significant amounts of U are applied on agricultural soils with mineral phosphorus fertilizers; thus, entering the food chain. The daily intake of U with solid food varies only slightly. It is lowest with a mixed standard diet (1.3 µg/day U) and highest with a vegan diet (2.0 µg/day U). It is the U content of tap and mineral water which determines the total U intake (1.7 – 7.1 µg/day U). Next to U speciation and amount of U entering the human body, an oversupply with phosphorus, and a critical supply with calcium and iron may amplify negative health effects. Kidneys are the prime target of a high P intake and U toxicity. The additional daily phosphorus intake by food phosphates peaked to 1000 mg/day in the last 20 years. This may add on an average 1.2 µg/day U and worst case 11 µg/day U to the solid diet. Toxicological studies suggest that damages of kidneys can be expected when the U content is as low as 0.1-0.4 µg/g U. The study provides a comprehensive overview of potential health hazards caused by dietary uranium intake in relation to nutritional habits.

Study objective To analyze the efficacy of intestinal ultrasonography with bowel preparation (TVUSBP) for endometriosis mapping in evaluating intestinal endometriosis to choose the surgical technique (segmental resection or linear nodulectomy) for treatment. Design Cross-sectional observational study. Setting University Hospital—Center for Advanced Endoscopic Gynecologic Surgery from April 2010 to November 2014. Patient(s) One hundred and eleven women with clinically suspected endometriosis and intestinal endometriotic nodule or intestinal adherence in TVUSBP for endometriosis mapping. Intervention(s) All patients with suspected endometriosis underwent TVUSBP for endometriosis mapping prior to videolaparoscopy for complete excision of endometriosis foci, including intestinal foci, using the linear nodulectomy or segmental resection techniques, depending on the characteristics of the intestinal lesion with confirmation of endometriosis on anatomopathological examination. Measurements and main results Preoperative ultrasonographic assessment of the length of the intestinal nodule, circumference of the intestinal loop affected by the endometriotic lesion, distance from the anal verge and intestinal wall layers infiltrated by endometriosis, as well as other endometriosis sites. Of the 111 patients who participated in the study, 63 (56.7%) presented intestinal endometriotic nodules in ultrasonography, performed by a single examiner (A.L.A.N.), and underwent intestinal surgical treatment of deep endometriosis—linear nodulectomy or segmental resection. The analysis of the receiver operating characteristic (ROC) curve showed that a longitudinal length of the intestinal nodule of 2.25 cm and a loop circumference of 27% are cutoff points separating linear nodulectomy from segmental resection techniques for excising intestinal endometriosis. The information obtained by TVUSBP helps the surgeon and patient, in the preoperative period, to select the surgical technique to be performed for resection of intestinal endometriosis and plan the surgical procedure while taking into account postoperative morbidity.

The half-sandwich complex [Cp′Fe(μ-I)]2 (1; Cp′ = η5-1,2,4-(Me3C)3C5H2) is cleaved when heated in toluene to form a cation–anion pair [{Cp′Fe(η6-toluene)}+{Cp′FeI2}−] (2), in which the two Fe(II) atoms adopt different spin states, i.e., a low-spin (S = 0) and a high-spin (S = 2) configuration. Upon oxidation of 1 with C2H4I2, the thermally stable 15VE species [Cp′FeI2] (3) can be isolated, in which the Fe(III) atom adopts an intermediate spin (S = 3/2) configuration. Complex 3 is an excellent starting material for further functionalizations and it reacts with Mg(CH2SiMe3)2 to form the unprecedented Fe(III) (S = 3/2) bis(alkyl) complex [Cp′Fe(CH2SiMe3)2] (4). The respective spin states of complexes 2–4 are confirmed by single-crystal X-ray crystallography, zero-field 57Fe Mossbauer spectroscopy, and solid-state magnetic susceptibility measurements. In contrast to the related 14VE high-spin (S = 2) Fe(II) alkyl species [Cp′FeCH(SiMe3)2], which resists the reaction with H2 as a consequence of a spin-induced reaction barrier, complex 4 reacts cleanly with H2 (8 bar) in cyclohexane to yield iron hydrides [{Cp′Fe}2(μ-H)3] (5) and [Cp′Fe(μ-H)2]2 (6) in a 1 : 4 ratio. However, when the hydrogenation of 4 is carried out in benzene, a green 19VE [Cp′Fe(η6-C6H6)] (A) intermediate is formed, which dimerizes to the bis(cyclohexadienyl)-bridged product [(Cp′Fe)2(μ2–η5:η5-C12H12)] (7). Further evidence for the intermediacy of [Cp′Fe(η6-C6H6)] (A) was gathered by X-band EPR and UV/vis spectroscopy. Interestingly, attempts to oxidize 7 with AgSbF6 proceeded via C–C bond cleavage instead of metal oxidation to form [Cp′Fe(C6H6)][SbF6] (8).

The concentration of toxic elements present in surface water of Sutlej River and Harike wetland besides Eichhornia crassipes, commonly known as water hyacinth, is estimated employing inductively coupled plasma mass spectrometry (ICP‐MS). Toxic elements such as cadmium (Cd), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), uranium (U), and zinc (Zn) are identified in the river as well as in Harike wetland catchment. Accumulation of elements in different parts of the water hyacinth plant is observed with the roots exhibiting maximum affinity followed by stem and then leaves. The removal efficacy of pollutants by water hyacinth is estimated using bioconcentration factor (BCF) index. It is found to be different for different elements, with Mn showing the highest and U the lowest magnitude. The study carried out in the present work indicates that rhizofiltration could play an important role in controlling pollutant load.

Phosphate rocks (PRs) used in fertilizer production contain uranium (U), which enters agricultural soils through phosphorus fertilization. However, our knowledge is still limited and cannot explain the different levels of U contamination found in agricultural systems. The paper reviewed the spatial and temporal U variations in PRs to obtain a comprehensive overview of U levels in various PRs worldwide and to investigate why U concentrations in igneous PRs are significantly lower compared to sedimentary PRs, and why less U is present in old sedimentary PRs (Precambrian-Cambrian) than in younger PRs (Ordovician-Neogene). In addition, the natural oxygen isotope compositions of phosphate (δ18Op) in various PRs were determined to identify their origins in relation to their U concentration. The δ18Op values differed among igneous PRs, old sedimentary PRs, and younger sedimentary PRs. Generally, the PRs with low δ18Op values had low U concentrations. In igneous PRs, low U concentrations were due to the lack of secondary U enrichment processes after rock formation, with low δ18Op values resulting from limited isotope fractionation at high temperature. Conversely, in sedimentary PRs, both U concentrations and δ18Op values were influenced by paleoclimate and paleogeographic features. Overall, there is a time-dependent coincidence of processes altering U concentration and δ18Op signatures of sedimentary PRs in a similar direction.

The half-sandwich complex [Cp'Fe(μ-I)]

Addition of N-heterocyclic carbenes (L = 1,3-di-tert-butylimidazol-2-ylidene (ItBu), 1,3-di-iso-propyl-4,5-dimethylimidazol-2-yildene (IiPr2Me2), 1,3-mesitylimidazol-2-yildene (IMes) and 1,3-di-(2,6-di-isopropylphenyl)imidazol-2-yildene (IPr)) to the iron half-sandwich complex [Cp′FeI]2 (Cp′ = η5-1,2,4-(Me3C)3C5H2, 1) forms the neutral, 16VE adducts [Cp′FeI(L)] (2–5) in moderate to excellent yields. These complexes were structurally characterised. The NHC ligand binds strongly to the Fe(II) atom, so that no exchange is observed on the NMR and chemical time scale. Fe(II) atoms in the starting material 1 adopt a high-spin configuration (S = 2) and are weakly antiferromagnetically coupled at low temperatures. Furthermore, in contrast to previous reports on related [(η5-C5Me5)FeCl(NHC)] systems, in which the Fe(II) atoms assume an intermediate spin (S = 1), no spin state change occurs upon coordination of the NHC ligand; the Fe(II) atoms in complexes 2–5 retain their high-spin state (S = 2) as shown by solid state magnetic susceptibility and zero-field 57Fe Mossbauer spectroscopy investigations. Density functional theory (DFT) studies at the B3LYP level of theory also agree with a well separated S = 2 ground state for compounds 2–5. Surprisingly for Fe(II) high-spin systems, compounds 1–5 exhibit slow paramagnetic relaxation in their Mossbauer spectra; this can be traced to spin–spin and spin–lattice relaxation processes with unusually large spin–lattice relaxation barriers. A structural model is proposed that associates these processes with crystal packing effects.

Salt metathesis of [Cp′FeI]2 [1, Cp′ = η5-1,2,4-(Me3C)3C5H2] and NaBH4 (2 equiv.) in tetrahydrofuran yields the low-spin iron complex [Cp′Fe(η3-BH4)] (2), which is thermally unstable and degrades slowly to the trimeric complex [Cp′FeBH2]3 (3) and H2. Both molecules have been fully characterized by various spectroscopic techniques. An X-ray structure analysis of 3 confirms its nature and reveals rather long B–B distances of 1.883(9) A. DFT methods in combination with three complementary approaches [Wiberg bond indices (WBI), atoms in molecules (AIM) and compliance constants] have been used to explain the bonding in these iron(II) complexes. All methods predict a weak bonding interaction between the boron atoms in 3.

Facile pseudohalide activation occurs in the reaction of SCN–, SeCN– and N3– with the iron half-sandwich [Cp′Fe(μ-I)]2., The iron half-sandwich [Cp′Fe(μ-I)]2 (Cp′ = 1,2,4-(Me3C)3C5H2, 1) reacts with the pseudohalides NCO–, SCN–, SeCN– and N3– to give [Cp′Fe(μ-NCO)]2 (2), [Cp′Fe(μ-S)]2 (3), [Cp′Fe(μ-Se2)]2 (4) and [Cp′Fe(μ-N)]2 (5), respectively. Various spectroscopic techniques including X-ray diffraction, solid-state magnetic susceptibility studies and 57Fe Mössbauer spectroscopy were employed in the characterization of these species. Mössbauer spectroscopy shows a decreasing isomer shift with increasing formal oxidation state, ranging from Fe(ii) to Fe(iv), in complexes 1 to 5. The sulfido-bridged dimer 3 exhibits strong antiferromagnetic coupling between the Fe(iii) centers. This leads to temperature-independent paramagnetism (TIP) at low temperature, from which the energy gap between the ground and the excited state can be estimated to be 2J = ca. 700 cm–1. The iron(iv) nitrido complex [Cp′Fe(μ-N)]2 (5) shows no reactivity towards H2 (10 atm), but undergoes clean reactions with CO (5 bar) and XylNC (Xyl = 2,6-Me2C6H3) to form the diamagnetic isocyanate and carbodiimide complexes [Cp′Fe(CO)2(NCO)] (7) and [Cp′Fe(CNXyl)2(NCNXyl)] (8), respectively. All compounds were fully characterized, and density functional theory (DFT) computations provide useful insights into their formation and the electronic structures of complexes 3 and 5.

bibtex: ISI:000400553000098 bibtex\location:'THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND',publisher:'ROYAL SOC CHEMISTRY',type:'Article',affiliation:'Walter, MD (Reprint Author), Tech Univ Carolo Wilhelmina Braunschweig, Inst Anorgan & Analyt Chem, Hagenring 30, D-38106 Braunschweig, Germany. Maron, L (Reprint Author), Univ Toulouse, INSA UPS LPCNO, CNRS LPCNO, 135 Ave Rangueil, F-31077 Toulouse, France. Reiners, Matthias; Maekawa, Miyuki; Daniliuc, Constantin G.; Freytag, Matthias; Jones, Peter G.; Walter, Marc D., Tech Univ Carolo Wilhelmina Braunschweig, Inst Anorgan & Analyt Chem, Hagenring 30, D-38106 Braunschweig, Germany. White, Peter S., Univ N Carolina, Dept Chem, CB 3290, Chapel Hill, NC 27599 USA. Hohenberger, Johannes; Sutter, Joerg; Meyer, Karsten, Univ Erlangen Nurnberg, Dept Chem & Pharm, Inorgan Chem, Egerlandstr 1, D-91058 Erlangen, Germany. Maron, Laurent, Univ Toulouse, INSA UPS LPCNO, CNRS LPCNO, 135 Ave Rangueil, F-31077 Toulouse, France.','author-email':'laurent.maron@irsamc.ups-tlse.fr mwalter@tu-bs.de',da:'2018-12-05','doc-delivery-number':'ET8MH',eissn:'2041-6539','funding-acknowledgement':'Alexander von Humboldt Foundation; NSF [CHE-0615704]; Emmy Noether and Heisenberg program [WA 2513/2, WA 2513/6]; Humboldt Foundation','funding-text':'We thank the Alexander von Humboldt Foundation for a Feodor-Lynen Fellowship (M. D. W.) and Prof. Maurice Brookhart for providing financial support (through NSF Grant CHE-0615704) and laboratory facilities (M. D. W.) during the initial phase of this research program. Deutsche Forschungsgemeinschaft (DFG) is acknowledged for generous funding by the Emmy Noether and Heisenberg program (WA 2513/2 and WA 2513/6, respectively). LM is grateful to the Humboldt Foundation for a grant of experienced researcher and the Chinese Academy of Science. CalMip is also gratefully acknowledged for a generous computational grant.','journal-iso':'Chem. Sci.','keywords-plus':'FE2O2 DIAMOND CORE; STRUCTURAL-CHARACTERIZATION; DINITROGEN ACTIVATION; SULFUR CLUSTERS; SOLVENT PURIFICATION; MOLECULAR-STRUCTURES; ELECTRON-TRANSFER; 2FE-2S CLUSTERS; DOUBLE-BOND; FE-IVN','number-of-cited-references':'106',oa:'DOAJ Gold','orcid-numbers':'Meyer, Karsten/0000-0002-7844-2998 Daniliuc, Constantin G./0000-0002-6709-3673','research-areas':'Chemistry','researcherid-numbers':'Meyer, Karsten/G-2570-2012 Walter, Marc/E-4479-2012','times-cited':'4','unique-id':'ISI:000400553000098','usage-count-last-180-days':'4','usage-count-since-2013':'20','web-of-science-categories':'Chemistry, Multidisciplinary'\; International audience; The iron half-sandwich [Cp'Fe(mu-I)](2) (Cp' = 1,2,4-(Me3C)(3)C5H2, 1) reacts with the pseudohalides NCO-, SCN-, SeCN- and N-3(-) to give [Cp'Fe(mu-NCO)](2) (2), [Cp'Fe(mu-S)](2) (3), [Cp'Fe(mu-Se-2)](2) (4) and [Cp'Fe(mu-N)](2) (5), respectively. Various spectroscopic techniques including X-ray diffraction, solid-state magnetic susceptibility studies and Fe-57 Mossbauer spectroscopy were employed in the characterization of these species. Mossbauer spectroscopy shows a decreasing isomer shift with increasing formal oxidation state, ranging from Fe(II) to Fe(IV), in complexes 1 to 5. The sulfido-bridged dimer 3 exhibits strong antiferromagnetic coupling between the Fe(III) centers. This leads to temperature-independent paramagnetism (TIP) at low temperature, from which the energy gap between the ground and the excited state can be estimated to be 2J = ca. 700 cm(-1). The iron(IV) nitrido complex [Cp'Fe(mu-N)](2) (5) shows no reactivity towards H-2 (10 atm), but undergoes clean reactions with CO (5 bar) and XylNC (Xyl = 2,6-Me2C6H3) to form the diamagnetic isocyanate and carbodiimide complexes [Cp'Fe(CO)(2)(NCO)] (7) and [Cp'Fe(CNXyl)(2)(NCNXyl)] (8), respectively. All compounds were fully characterized, and density functional theory (DFT) computations provide useful insights into their formation and the electronic structures of complexes 3 and 5.

Hybrid films of TiO 2 and benzoquinone, its derivative 2-methyl-benzoquinone or the dye 2,9,16,23-tetrasulfophthalocyaninatonickel(II) were prepared by anodic electrodeposition from titanium alkoxide solutions. Calcination of the films at 450 °C led to removal of the organics and the formation of crystalline and highly porous TiO 2 films as seen in XRD and Kr adsorption measurements, respectively. In dye-sensitized solar cells the films achieved an overall light-to-electricity conversion efficiency of 0.8% despite a low film thickness of 0.55 μm. In the photocatalytic decomposition of methylene blue the films showed photonic efficiencies of up to 0.09% for film thicknesses around 0.5 μm, which is much higher than those of comparable TiO 2 films prepared by sol–gel method.

Crystalline TiO2 films can be formed by anodic electrodeposition from TiCl3 solution. In this study we investigated the co-deposition of TiO2 with different organic dye molecules as structure-directing agents. The best results were obtained with the pH-indicator bromothymol blue, which leads to the formation of thick, crystalline and porous films. The films were tested in dye-sensitized solar cells and gave a five times higher efficiency compared to the film deposited with sodium dodecyl sulfate in our earlier study.

We examined the relationship between the values of plasma protein induced by vitamin K absence or antagonist II (PIVKA-II) and serum α-fetoprotein (AFP) and the presence of AFP mRNA in the mononuclear cells of the peripheral blood in 50 patients with hepatocellular carcinoma (HCC) . AFP mRNA in the blood was detected in 26 of 50 patients with HCC (52.0%). The frequency of positive cases in each TNM stage was: none of 5 in stage I, 3 of 14 (21.4%) in stage II, 6 of 10 (60.0%) in stage III and 17 of 21 (81.0%) in stage IV. AFP mRNA was detected more frequently in patients with high serum AFP level (400 ng/ml and more than 400 ng/ml) (12/16, 75.0%) than in those with low AFP level (less than 400 ng/ml) (14/34, 41.2%) (P

A series of manganese, iron and cobalt complexes bearing sterically demanding 1,3-disubstituted indenyl ligands, 1,3-(Me(3)C)(2)C(9)H(5) (Ind(tBu)) (1) and 1,3-(C(6)H(11))(2)C(9)H(5) (Ind(cHexyl)) (2), has been prepared. These complexes have been fully characterised by various spectroscopic techniques, elemental analysis, and X-ray diffraction experiments. In addition the electronic and steric properties of these ligands have been evaluated. Although the cone angles and electronic properties are similar to 1,2,4-(Me(3)C)(3)C(5)H(2) (Cp'), indenyl iron half-sandwich complexes are only stable at low temperature. This has been demonstrated for 1-FeI using suitable trapping experiments such as CO or NaCp' addition to yield 1-Fe(CO)(2)I and 1-FeCp', respectively. Overall the metal-ligand bonds in these indenyl compounds are weaker than in the corresponding cyclopentadienyl derivatives. In addition, the bis(indenyl)manganese complexes, 1-Mn and 2-Mn, are high-spin, as established by solid state magnetic susceptibility studies in the temperature range 2-300 K.

The sterically encumbered 1,2,4-(Me3C)3C5H2 (Cp′) ligand allows the synthesis of stable high spin mono(cyclopentadienyl) manganese complexes [Cp′MnX(thf)]2 (X = Cl, Br, I; 1-X). Thermal stabilities of 1-X toward ligand redistribution to [Cp2′Mn] (2) and MnX2 depend on the bridging halide ligand. The kinetic stability of 1-I in solution even at elevated temperatures is noteworthy. Complexes 1 are useful starting materials for further functionalizations. Metathesis of 1-Cl with [LiN(SiMe3)2(OEt2)]2 yields the 13 valence-electron (VE) complex, [Cp′MnN(SiMe3)2] (3), while the manganese polyhydride cluster, [{Cp′Mn}4{MnH6}], was formed in the reaction of 1-I and KHBEt3. The 17 VE [MnH6]4− core of 4 is effectively shielded by four high spin [Cp′Mn]+ units. Magnetic susceptibility studies on 4 suggest weak electron exchange coupling between the spin carriers, but the spin state of the central [MnH6]4− fragment remained ambiguous. Therefore, the electronic structure of 4 was also analyzed by broken symmetry (BS) DFT calculations, which provided strong evidence for a low spin [MnH6]4− unit in agreement with previous spectrochemical studies performed on [FeH6]4−.

A combination of phase-transfer and traditional alkylation strategies has been employed to synthesise sterically encumbered 1,3-di(cyclohexyl) and 1,3-di(tert-butyl) substituted indenes in multi-gram quantities. These indenyl ligands and sterically demanding alkyl cyclopentadienyl ligands have been used to prepare a series of [(η(7)-C(7)H(7))Zr(η(5)-L)] (L = Cp and Ind) complexes by straightforward salt metathesis between [(η(7)-C(7)H(7))ZrCl(tmeda)] and the corresponding sodium indenide or cyclopentadienide. All of these Zr complexes have been characterized by elemental analysis, NMR spectroscopy and single crystal X-ray diffraction. The structural information derived from these studies was employed to evaluate the steric demand of these ligands in a realistic manner.