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The eletrochemical properties of Group 15 quaternary alkyl bistriflimides salts were reported. The ionic liquids with potential application in electropositive metal deposition when used as supporting electrolytes in MeCN was also discussed. It was found that the three Group 15 based ionic liquids that were prepared have extremely large electrochemical windows.

Background: Collecting duct carcinoma (CDC) is a rare and aggressive variant of renal cell carcinoma (RCC), which has poor response to cytokine therapy and chemotherapy. Introduction of tyrosine kinase inhibitors (TKIs), in particular sorafenib and sunitinib, is changing the treatment paradigm for management of RCC. However, patients with CDC have been excluded from the majority of randomised trials involving the use of TKIs. Case Report: Our patient with metastatic CDC was treated with sorafenib, and demonstrated an excellent response, both clinically and radiologically. She continues on sorafenib treatment with minimal toxicity, and has demonstrated a progressionfree survival exceeding 13 months. Conclusions: This is the first reported case of a patient with CDC responding to sorafenib treatment. Therefore, the role of sorafenib in the management of metastatic CDC needs prospective evaluation.

[Ru(bpy)(2)(Mebpy-COOH)](PF(6))(2).3H(2)O (1), [Ru(phen)(2)(Mebpy-COOH)](ClO(4))(2).5H(2)O (2), [Ru(dppz)(2)(Mebpy-COOH)]Cl(2).9H(2)O (3), and [Ru(bpy)(dppz)(Mebpy-COOH)](PF(6))(2).5H(2)O (4) (bpy = 2,2'-bipyridine, Mebpy-COOH = 4'-methyl-2,2'-bipyridine-4-carboxylic acid, phen = 1,10-phenanthroline, dppz = dipyrido[3,2,-a;2',3-c]phenazine) have been synthesized and characterized spectroscopically and by microanalysis. The [Ru(Mebpy-COOH)(CO)(2)Cl(2)].H(2)O intermediate was prepared by reaction of the monocarboxylic acid ligand, Mebpy-COOH, with [Ru(CO)(2)Cl(2)](n), and the product was then reacted with either bpy, phen, or dppz in the presence of an excess of trimethylamine-N-oxide (Me(3)NO), as the decarbonylation agent, to generate 1, 2, and 3, respectively. For compound 4, [Ru(bpy)(CO)Cl(2)](2) was reacted with Mebpy-COOH to yield [Ru(bpy)(Mebpy-COOH)(CO)Cl](PF(6)).H(2)O as a mixture of two main geometric isomers. Chemical decarbonylation in the presence of dppz gave 4 also as a mixture of two isomers. Electrochemical and spectrophotometric studies indicated that complexes 1 and 2 were present as a mixture of protonated and deprotonated forms in acetonitrile solution because of water of solvation in the isolated solid products. The X-ray crystal structure determination on crystals of [Ru(bpy)2(MebpyCOO)][Ru(bpy)(2)(MebpyCOOH)](3)(PF(6))(7), 1a, and [Ru(phen)(2)(MebpyCOO)](ClO(4)).6H(2)O, 2a, obtained from solutions of 1 and 2, respectively, revealed that 1a consisted of a mixture of protonated and deprotonated forms of the complex in a 1:3 ratio and that 2a consisted of the deprotonated derivative of 2. A distorted octahedral geometry for the Ru(II) centers was found for both complexes. Upon excitation at 450 nm, MeCN solutions of the protonated complexes 1-4 were found to exhibit emission bands in the 635-655 nm range, whereas the corresponding emission maxima of their deprotonated forms were observed at lower wavelengths. Protonation/deprotonation effects were also observed in the luminescence and electrochemical behavior of complexes 1-4. Comprehensive electrochemical studies in acetonitrile show that the ruthenium centers on 1, 2, 3, and 4 are oxidized from Ru(II) to Ru(III) with reversible potentials at 917, 929, 1052, and 1005 mV vs Fc(0/+) (Fc = ferrocene), respectively. Complexes 1 and 2 also exhibit an irreversible oxidation process in acetonitrile, and all compounds undergo ligand-based reduction processes.

Electrocrystallization of single nanowires and/or crystalline thin films of the semiconducting and magnetic Co[TCNQ]2(H2O)2 (TCNQ=tetracyanoquinodimethane) charge-transfer complex onto glassy carbon, indium tin oxide, or metallic electrodes occurs when TCNQ is reduced in acetonitrile (0.1 M [NBu4][ClO4]) in the presence of hydrated cobalt(II) salts. The morphology of the deposited solid is potential dependent. Other factors influencing the electrocrystallization process include deposition time, concentration, and identity of the Co2+(MeCN) counteranion. Mechanistic details have been elucidated by use of cyclic voltammetry, chronoamperometry, electrochemical quartz crystal microbalance, and galvanostatic methods together with spectroscopic and microscopic techniques. The results provide direct evidence that electrocrystallization takes place through two distinctly different, potential-dependent mechanisms, with progressive nucleation and 3-D growth being controlled by the generation of [TCNQ]*- at the electrode and the diffusion of Co2+(MeCN) from the bulk solution. Images obtained by scanning electron microscopy reveal that electrocrystallization of Co[TCNQ]2(H2O)2 at potentials in the range of 0.1-0 V vs Ag/AgCl, corresponding to the [TCNQ]0/*- diffusion-controlled regime, gives rise to arrays of well-separated, needle-shaped nanowires via the overall reaction 2[TCNQ]*-(MeCN)+Co2+(MeCN)+2H2O right harpoon over left harpoon {Co[TCNQ]2(H2O)2}(s). In this potential region, nucleation and growth occur at randomly separated defect sites on the electrode surface. In contrast, at more negative potentials, a compact film of densely packed, uniformly oriented, hexagonal-shaped nanorods is formed. This is achieved at a substantially increased number of nucleation sites created by direct reduction of a thin film of what is proposed to be cobalt-stabilized {(Co2+)([TCNQ2]*-)2} dimeric anion. Despite the potential-dependent morphology of the electrocrystallized Co[TCNQ]2(H2O)2 and the markedly different nucleation-growth mechanisms, IR, Raman, elemental, and thermogravimetric analyses, together with X-ray diffraction, all confirmed the formation of a highly pure and crystalline phase of Co[TCNQ]2(H2O)2 on the electrode surface. Thus, differences in the electrodeposited material are confined to morphology and not to phase or composition differences. This study highlights the importance of the electrocrystallization approach in constructing and precisely controlling the morphology and stoichiometry of Co[TCNQ]2-based materials.

There is little consensus regarding long-term followup of renal function in patients who undergo urinary diversion. We established the usefulness of combined serial isotopic glomerular filtration rate measurement and diuresis renography in the early identification of patients at risk for deterioration of renal function following ileal conduit diversion.A total of 340 patients with ileal conduit diversion who were followed between 1990 and 2000 were identified. We analyzed data on 178 patients who had more than 4 years of followup. Renal function was assessed by serial estimation of serum creatinine, isotopic glomerular filtration rate and diuresis renographic measurements.Of the patients 52 (29%) demonstrated a worsening glomerular filtration rate. Mean followup +/- SEM was 8.2 +/- 0.4 years (range 4 to 30) and 67% of patients had more than 6 years of followup. In this group we found that hypertension, recurrent urinary sepsis and an initial post-diversion glomerular filtration rate of less than 50 ml per minute per 1.73 m were prevalent risk factors. Hypertension was an independent predictor of a decreased glomerular filtration rate in this group. Of 52 patients with a deteriorating glomerular filtration rate 19 had type II or IIIb curves on followup renography, of whom 13 underwent revision surgery. Renal function subsequently stabilized or improved in this group.Of patients with an ileal conduit 29% have renal function deterioration in the long term. No surgical cause for glomerular filtration rate deterioration was found in 18%. Important predisposing factors in nonobstructed cases were hypertension, recurrent urinary sepsis and a glomerular filtration rate of less than 50 ml per minute per 1.73 m. Hypertension was an independent predictor of a decreased glomerular filtration rate in the group with worsening glomerular filtration rates. In 11% of patients deterioration was due to upper tract obstruction. This was identifiable using renography and the glomerular filtration rate. A type IIIb curve was an early indicator of obstruction.

The reduction of selected lanthanide cations to the zerovalent state in the room-temperature ionic liquid [Me3N(n)Bu][TFSI] is reported (where TFSI = bistriflimide, [N(SO2CF3)2]-). The lanthanide cations were introduced to the melt as the TFSI hydrate complexes [Ln(TFSI)3(H2O)3] (where Ln = La(III), Sm(III) or Eu(III)). The lanthanum compound [La(TFSI)3(H2O)3] has been crystallographically characterized, revealing the first structurally characterized f-element TFSI complex. The lanthanide in all three complexes was shown to be reducible to the metallic state in [Me3N(n)Bu][TFSI]. For both the Eu and Sm complexes, reduction to the metallic state was achieved via divalent species, and there was an additional observation of the electrodeposition of Eu metal.

To determine the effect of perioperative distal vasal lavage with 50 mL of normal saline on subsequent time to azoospermia after vasectomy.Seventy-two patients were prospectively enrolled and randomized to undergo vasectomy with or without vasal lavage. Infertility rates at 8, 10 and 12 weeks were compared for both groups and for those undergoing the procedure under local or general anaesthesia. Patient compliance for returning postoperative semen for analysis was also assessed.There was no statistically significant difference in infertility rates at 8, 10 or 12 weeks after vasectomy with or without vasal lavage. Vasectomies performed under local and general anaesthesia had comparable rates of infertility at 12 weeks after surgery. Compliance in providing semen for analysis was poor.The routine adoption of distal vasal lavage during vasectomy for contraception cannot be recommended. As compliance in providing semen for analysis was poor, the clinician has a responsibility to remind the patient of the consequences of such action.

In batteries the separator plays a crucial role within the cell. Commercially available separators, e.g. polyolefins, glass fibres, or polyolefins with ceramic coatings, do not have ideal compatibility with ionic liquid (IL) electrolytes. In this study, we report on the use of electrospinning to fabricate poly(vinylidene fluoride) (PVDF) membranes for use with IL electrolyte based batteries. Four electrospun membranes have been prepared; a neat PVDF, PVDF doped with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and two LiTFSI-doped membranes based on either thermal or UV cross-linking. The membranes were characterised by a number of techniques and the key characteristics of all electrospun membranes included small fibre sizes and high porosity. The tensile strengths of the cross-linked membranes approached those of commercial membranes. Electrochemical performance was measured using coin cell cycling and the thermally cross-linked membrane gave the lowest cell overpotential as well as the lowest cell resistance.

not Available.

The effect of storage time on the cyclability of lithium electrodes in an ionic liquid electrolyte, namely 0.5 m LiBF4 in N-methyl-N-propyl pyrrolidinium bis(fluorosulfonyl)imide, [C3mpyr+][FSI–], was investigated. A chemical interaction was observed which is time dependent and results in a morphology change of the Li surface due to build up of passivation products over a 12‐day period. The formation of this layer significantly impacts on the Li electrode resistance before cycling and the charging/discharging process for symmetrical Li|0.5 m LiBF4 in [C3mpyr+][FSI–]|Li coin cells. Indeed it was found that introducing a rest period between cycling, and thereby allowing the chemical interaction between the Li electrode and electrolyte to take place, also impacted on the charging/discharging process. For all Li surface treatments the electrode resistance decreased after cycling and was due to significant structural rearrangement of the surface layer. These results suggest that careful electrode pretreatment in a real battery system will be required before operation.

The polymerisation reaction of pyrrole and 3,4-ethylenedioxythiophene using the chemical oxidant FeCl3·6H2O in the room temperature ionic liquid butyl-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (C4mpyrTFSI) has been investigated using cyclic voltammetry, UV/vis and IR spectroscopy. The voltammetric data for the Fe2+/3+ reaction is complicated by the presence of H+ introduced upon dissolution of the iron salt by deprotonation of the coordinated waters. The voltammetric and chemical reaction studies show that H+ itself, introduced to solution as trifluoromethanesulfonic acid (HTFSI), can act as the chemical oxidant for the polymerisation reaction. Voltammetric data also implies that in this system the Fe2+/3+ redox couple may not actually be involved in the polymerisation reaction and that the H+ introduced upon dissolution of the FeCl3·6H2O may be the sole cause of the oxidation reaction.

I refer to the article “Excess Enthalpies of Binary and Ternary Mixtures Containing Dibutyl Ether, Cyclohexane, and 1Butanol at 298.15 K” by Aguilar et al. in J. Chem. Eng. Data, 2009, 54, 1672 1679 and Corrections in J. Chem. Eng. Data, 2009, 54, 2341 2342. I used the Redlich Kister eq 1 with constants given in Table 4 of the original paper, to calculate the excess enthalpy of a binary (H). I found that eq 1 is incorrect. It should read as below. H 1⁄4 xð1 xÞ 3 1⁄2∑ n

Room temperature ionic liquids (RTILs) with the bis(fluorosulfonyl)imide (FSI) anion exhibit higher conductivities than the corresponding bis(trifluoromethanesulfonyl)imide (TFSI) compounds, thereby generating interest as novel electrolytes for lithium batteries. The electrochemical properties of a series of FSI RTILs, at inert metal and lithium electrodes, have been investigated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy. Addition of LiBF 4 , LiPF 6 , or LiTFSI extends cathodic limits to significantly more negative values and allows reversible lithium electrodeposition. Variable-current cycling of symmetrical Li | Li coin cells reveals significant changes in electrode-electrolyte interphasial impedance, which depends on the identity of the lithium salt anion, the concentration of the salt, and the RTIL cation. For most cells, voltage-time curves become unsteady early in duty, which is consistent with the formation of dendrites on the lithium surface. A stable voltage behavior returns within around 20 cycles, at notably a lower current density presumably because detachment/reattachment of dendrites eventually re-establishes a contiguous lithium electrode with a higher surface area. Importantly, the combination of the kinetics of lithium deposition and morphology of the deposit in FSI anion-based RTIL media does not result in lithium penetration of the separator. Therefore, FSI-based electrolytes can play a key role in the development of a viable lithium-metal battery technology.

In seeking to develop ionic liquid based electrolytes for use in lithium metal batteries, we present an investigation of the electrochemical properties of N-propyl-N-methyl-pyrrolidinium bis(fluorosulfonyl)imide and lithium bis(fluorosulfonyl)imide at Ni, Pt, and Li electrodes by cyclic voltammetry, chronoamperometry, and impedance spectroscopy. While lithium electrodeposition and stripping are chemically reversible, the magnitude of peak currents during successive cycles is strongly dependent on the substrate. Severe decreases are observed at Ni, only moderate falls at Pt, while Li electrodes support modest increases in current, consistent with roughening of the electrode with each deposition cycle. We discuss this behavior on the basis of competition between (i) formation of a solid electrolyte interphase at the deposited lithium surface and (ii) strength of interaction between deposited lithium and substrate. Chronoamperometric data indicate that lithium deposition proceeds via instantaneous nucleation and growth, which favors smooth rather than nodular deposit morphology. Symmetrical (Li|electrolyte|Li) cells display excellent cycling behavior (>470 cycles), at current densities up to 10 mA cm ―2 , with only transient evidence of dendrite formation. Initially high impedance is reduced by increasing the concentration (∼0.5 mol kg ―1 ) of lithium salt, although all cells eventually reach relatively low values of < 10 Ω cm 2 . The properties of this electrolyte system make it a strong candidate for future application in lithium metal batteries.

The in situ reduction of dissolved Ag+ or Au3+ to the zero valent state in the distillable ionic liquid DIMCARB is reported. The reduction process leads to both 1D and 3D nanostructure formation, i.e. nanoparticles and nanowires and clusters composed of nanoparticles. The nanostructures formed have been characterised using UV/vis spectroscopy, powder X-ray diffraction and atomic force microscopic (AFM) topographic and phase imaging. Ag nanostructure growth occurs as a solution based crystallisation process. However, real time AFM imaging of Ag nanostructures formed when poly(vinyl pyrrolidone) is present shows the growth of nanowires on a mica surface via a surface confined process involving Ag atom diffusion. The growth of Au nanowires also occurs via the surface diffusion process. Based on the experimental results, a nanostructure growth mechanism in DIMCARB is proposed and 1D or 3D nanostructure growth is related to either a thermodynamic or a kinetic pathway.

The reaction of UO22+ with the trivacant lacunary polyoxometalate anions, [SbW9O33]9− and [TeW9O33]8−, yields the novel isostructural complexes [(UO2)2(H2O)2(SbW9O33)2]14− (1) and [(UO2)2(H2O)2(TeW9O33)2]12− (2), respectively. The complex anions contain two [XW9O33]n− (X = SbIII or TeIV) anions linked by two UO22+ cations. Each uranyl moiety bonds to two unsaturated oxygen atoms of each lacunary anion in the complex. Each [XW9O33]n− anion has six unsaturated oxygen atoms meaning that in 1 and 2 each [XW9O33]n− anion has two unsaturated oxygen atoms which remain uncoordinated to uranium with the result being the formation of an ‘open’ sandwich structure. The fact that a third UO22+ cation is not coordinated to form a ‘closed’ sandwich structure (as is observed for first row d-block transition metals) is attributed to the steric hindrance of the axial ‘yl’ oxygen atoms of the uranyl group. The products, prepared as NH4+ salts, have been characterised by single crystal X-ray diffraction, elemental analysis, TGA analysis, IR, Raman and UV/vis spectroscopy, which indicate that the O donor atoms of the lacunary heteropolytungstate anions are strongly coordinating to U(VI) in the equatorial plane, weakening the uranyl U–O axial bonds.

The surface ice taken from the snout of the Nehnar glacier (Kashmir) in western Himalaya has been dated using radioisotopes32Si and210Pb to be 500 years. Based on the age distribution of ice and the expected activity of32Si in the fallout, the average rate of glacier movement over a period of the last few centuries is estimated to be about 6 m/yr.