Facile formulation and fabrication of the cathode using a self-lithiated carbon for all-solid-state batteries.

We propose a innovative concept to boost the electrochemical performance of cathode composite electrodes using surface-modified carbons with hydrophilic moieties to increase their dispersion in a Lithium Nickel Manganese Cobalt Oxide (NMC) cathode and in-situ generate Li-rich carbon surfaces. Using a rapid aqueous process, the hydrophilic carbon is effectively dispersed in NMC particles followed by the conversion of its acid surface groups (e.g. -COOH), which interact with the NMC particles due to their basicity, into grafted Li salt (-COO-Li+). The solid-state batteries prepared using the cathode composites with surface-modified carbon exhibit better electrochemical performance. Such modified carbons led to a better electronic conduction path as well as facilitating Li+ ions transfer at the carbon/NMC interface due to the presence of lithiated carboxylate groups on their surface.

Microscopy and microanalysis of complex nanosized strengthening precipitates in new generation commercial Al-Cu-Li alloys.

Precipitates (ppts) in new generation aluminum-lithium alloys (AA2099 and AA2199) were characterised using scanning and transmission electron microscopy and atom probe tomography. Results obtained on the following ppts are reported: Guinier-Preston zones, T1 (Al2 CuLi), ß' (Al3 Zr) and δ' (Al3 Li). The focus was placed on their composition and the presence of minor elements. X-ray energy-dispersive spectrometry in the electron microscopes and mass spectrometry in the atom probe microscope showed that T1 ppts were enriched in zinc (Zn) and magnesium up to about 1.9 and 3.5 at.%, respectively. A concentration of 2.5 at.% Zn in the δ' ppts was also measured. Unlike Li and copper, Zn in the T1 ppts could not be detected using electron energy-loss spectroscopy in the transmission electron microscope because of its too low concentration and the small sizes of these ppts. Indeed, Monte Carlo simulations of EEL spectra for the Zn L2,3 edge showed that the signal-to-noise ratio was not high enough and that the detection limit was at least 2.5 at.%, depending on the probe current. Also, the simulation of X-ray spectra confirmed that the detection limit was exceeded for the Zn Kα X-ray line because the signal-to-noise ratio was high enough in that case, which is in agreement with our observations.

Nanometres-resolution Kikuchi patterns from materials science specimens with transmission electron forward scatter diffraction in the scanning electron microscope.

A charge-coupled device camera of an electron backscattered diffraction system in a scanning electron microscope was positioned below a thin specimen and transmission Kikuchi patterns were collected. Contrary to electron backscattered diffraction, transmission electron forward scatter diffraction provides phase identification and orientation mapping at the nanoscale. The minimum Pd particle size for which a Kikuchi diffraction pattern was detected and indexed reliably was 5.6 nm. An orientation mapping resolution of 5 nm was measured at 30 kV. The resolution obtained with transmission electron forward scatter diffraction was of the same order of magnitude than that reported in electron nanodiffraction in the transmission electron microscope. An energy dispersive spectrometer X-ray map and a transmission electron forward scatter diffraction orientation map were acquired simultaneously. The high-resolution chemical, phase and orientation maps provided at once information on the chemical form, orientation and coherency of precipitates in an aluminium-lithium 2099 alloy.

Simulating STEM imaging of nanoparticles in micrometers-thick substrates.

Scanning transmission electron microscope (STEM) images of three-dimensional (3D) samples were simulated. The samples consisted of a micrometer(s)-thick substrate and gold nanoparticles at various vertical positions. The atomic number (Z) contrast as obtained via the annular dark-field detector was generated. The simulations were carried out using the Monte Carlo method in the CASINO software (freeware). The software was adapted to include the STEM imaging modality, including the noise characteristics of the electron source, the conical shape of the beam, and 3D scanning. Simulated STEM images of nanoparticles on a carbon substrate revealed the influence of the electron dose on the visibility of the nanoparticles. The 3D datasets obtained by simulating focal series showed the effect of beam broadening on the spatial resolution and on the signal-to-noise ratio. Monte Carlo simulations of STEM imaging of nanoparticles on a thick water layer were compared with experimental data by programming the exact sample geometry. The simulated image corresponded to the experimental image, and the signal-to-noise levels were similar. The Monte Carlo simulation strategy described here can be used to calculate STEM images of objects of an arbitrary geometry and amorphous sample composition. This information can then be used, for example, to optimize the microscope settings for imaging sessions where a low electron dose is crucial for the design of equipment, or for the analysis of the composition of a certain specimen.

Examples of charging effects on the spectral quality of X-ray microanalysis on a glass sample using the variable pressure scanning electron microscope.

The performance of X-ray microanalysis in the variable pressure or environmental scanning electron microscope (VP-SEM or ESEM) is limited by skirting. Under certain conditions, charging effects can occur and change the X-ray emission, which affects the X-ray microanalysis. The conventional way to evaluate charging is to calculate the Duane-Hunt limit by fitting the X-ray intensity region located below the energy cut-off. Nevertheless, this method appears to have serious limitations for instance in the case of strong insulators. A perfect example of this limitation is to study the evolution of composition of an alkali glass with time. This paper reports on the evolution of the sodium X-ray intensity with time depending on accelerating voltage, pressure and presence of a surface coating. For certain conditions, a decrease of sodium X-ray intensity with time was observed but for other conditions the reverse behavior was noticed. The increase of sodium X-ray intensity with time was obtained when the force created by the surface electrons was stronger than the force generated by electrons trapped in the interaction volume, whereas the decrease of sodium X-ray intensity occurred when the force generated by electrons trapped in the interaction volume was the stronger. The variations of sodium X-ray intensity were also compared to the variation of the Duane-Hunt limit, the determination of which is studied in detail in this article.

Determination of E2 for nitride ceramics using FE-SEM and the Duane-Hunt limit procedure.

This work demonstrates the possibility of using the Duane-Hunt limit of the bremsstrahlung to determine E2 values of Si3N4 and AlN ceramics. The E(DHL) versus E0 graph demonstrates that for conductive materials, the experimental curve is parallel to the theoretical (E(DHL) = E0), but both curves cross in the case of insulators. The intersection points (E2 value), are 3.01 keV for Si3N4 and 2.67 keV for AlN. Imaging of ceramic grain structure at high magnification was performed to demonstrate the validity of the calculated E2 values.

Targeted hepatitis C lookback: Quebec, Canada.

BACKGROUND: Since March 1990, all blood donations in Canada are screened for antibodies to hepatitis C virus (HCV). Because HCV may cause chronic asymptomatic hepatitis, in February 1995, the Canadian Red Cross began targeted HCV lookback studies. STUDY DESIGN AND METHODS: From March 1990 to March 1997, the Quebec Center of the Canadian Red Cross collected 1,750,846 donations, and there were 561 anti-HCV-positive repeat donors, from whom 3,196 blood components had been issued to the hospitals. Hospital blood bank directors were asked to test recipients and return results to the Quebec Center. One hundred nine hospitals were surveyed to determine methods and resources involved in lookback. The transfusion medicine service at the Royal Victoria Hospital (RVH) developed a standard operating procedure for performing lookbacks and analyzed the costs and outcomes of lookbacks. RESULTS: As of April 1998, information has been received on 2329 (73%) of components; 1020 patients had died of unrelated causes, 590 were untraceable, and 353 were tested. Of those tested, 215 (61%) were anti-HCV positive; their average age was 47, and at least 53 percent were already aware of their HCV status. Few hospitals had received any additional resources to perform lookbacks. At the RVH, lookback on 182 components resulted in the identification of nine seropositive recipients, average age 70, who did not previously know their HCV status; four of these patients had abnormal alanine aminotransferase levels. The cost of lookback per newly diagnosed case of HCV was estimated at $2727 (US) for the Quebec Center and $6014 (US) for the RVH. CONCLUSION: Targeted lookback in the province of Quebec on 3196 components has resulted in the identification of 101 seropositive recipients who did not previously know their HCV status.

Pharmacokinetics of bisoprolol during repeated oral administration to healthy volunteers and patients with kidney or liver disease.

The pharmacokinetics of bisoprolol were investigated following oral administration of 10mg once daily for 7 days in 8 healthy subjects, in 14 patients with different degrees of renal impairment and in 18 patients with liver disease. In healthy subjects peak and trough steady-state concentrations of 52 micrograms/L and 11 micrograms/L, respectively, an elimination half-life of 10.0 hours and total body clearance of 14.2 L/h were observed. 5.21 mg/24 hours of unchanged bisoprolol were recovered following urinary excretion during the dosage interval. In 11 patients with renal impairment (mean CLCR = 28 +/- 5 ml/min/1.72m2) half-life was prolonged to 18.5 hours, and peak and trough concentrations were 74 and 32 micrograms/L, respectively. Correspondingly, urinary excretion decreased to 3.35 mg/24 hours and total body clearance to 7.8 L/h. In uraemic patients (CLCR less than 5 ml/min/1.73m2) the total clearance of bisoprolol was 5.0 L/h and the elimination half-life was 24.2 hours. In patients with liver cirrhosis half-life increased to 13.5 hours, steady-state peak and trough concentrations increased to 62 and 22 micrograms/L, respectively, and total body clearance decreased to 10.8 L/h. The present study indicates that in patients with impairment of kidney or liver function accumulation of bisoprolol above a factor of 2 did not occur. However, in the terminal stages of insufficiency of kidney or liver function bisoprolol dosage should not exceed 10mg.

[Minoxidil in the treatment of malignant hypertension (author's transl)]. / Minoxidil in der Behandlung der malignen Hypertonie.

In 21 of 23 patients with hypertension unresponsive to other treatment minoxidil, a new antihypertensive drug acting via peripheral vasodilatation, lowered their blood pressure from 191 +/- 19/117 +/- 12 MM Hg to 147 +/- 13/117 +/- 12 mm Hg. The drug causes a reflex tachycardia and must therefore be combined with beta-blockers. Furthermore, an effective diuretic must also be used because minoxidil causes sodium retention. Hypertrichosis is an important side-effect for which the drug may have to be discontinued, especially in young women. Orthostasis did not occur in the reported series. The authors recommend that the drug be made available for the treatment of malignant hypertension.

Pharmacokinetics of amikacin for treatment of urinary tract infections in patients with reduced renal function.

Amikacin (250 mg four times daily for 10 days) was administered intramuscularly to 22 patients with long-standing, severe infections of the urinary tract, in each case superimposed on chronic uropathy or nephropathy. Therapy with amikacin was completely successful in 14 patients (sterile 14-day follow-up urine specimens obtained by suprapubic needle aspiration of the bladder) and partially successful in three (sterile three-day but positive 14-day follow-up urine specimens). Five patients were judged to be treatment failures. Quantitative assessment of pyuria revealed a significant drop in the rate of excretion of white cells to near normal levels not only in patients who were cured but also in others, a finding which suggests that the infectious process had been affected by amikacin in all cases. The course of the disease in individual patients suggested that amikacin therapy can be successful after a long series of failures from treatment of such conditions with other antibiotics. Additional pharmacokinetic studies indicated that the half-life of amikacin may be increased five- to 10-fold in patients with renal insufficiency. A tentative dosage schedule was prepared for patients with various degrees of impaired renal function on the basis of average half-life values.