CO2 Electroreduction on Cu-Modified Platinum Single Crystal Electrodes in Aprotic Media

Techniques of electrode modification by copper deposits are developed that allow obtaining compact bulk quasi-epitaxial deposits on basal Pt(hkl) single crystal faces. The issues of the deposit roughness and characterization are discussed. Problems of drying and transferring electrodes with copper deposits into other solutions are considered. The obtained deposits are used for CO2 electroreduction in propylene carbonate and acetonitrile solutions of 0.1 M TBAPF6, and the relationship between the electrode surface structure and its electrocatalytic activity in CO2 electroreduction is discussed. We also demonstrate that the restructuring of Cu deposits occurs upon CO2 electroreduction. Complementary reactivity studies are presented for bare Pt(hkl) and Cu(hkl) single crystal electrodes. Cu-modified Pt(hkl) electrodes display the highest activity as compared to bare Pt(hkl) and Cu(hkl). Particularly, the Cu/Pt(110) electrode shows the highest activity among the electrodes under study. Such high activity of Cu/Pt(hkl) electrodes can be explained not only by the increasing actual surface area but also by structural effects, namely by the presence of a large amount of specific defect sites (steps, kinks) on Cu crystallites.

Kunstbüchlein. Auff mancherley weyß Dinten vnd allerhandt Farben zu bereiten : Auch Gold vnnd Silber, sampt allen Metallen auß der Federn zu schreyben, Mit vil anderen nützlichen künstlin. Schreybfedern vnnd Pergamen mit allerley Farben zu ferben ...

Fingerprint nach Ex. der UB Frankfurt

Schwarz-Roth-Gold: Liederbuch für Bürgerwehr, Volksheer und Turngemeinden : mit Melodieen

Boberach: Mit zwei kolorierten Illustrationen auf Umschlag und Umschlagrücken: Deutscher Doppeladler mit Krone, Fahnenträger einer Bürgerwehr. - Welsch (Projektbearbeiter): Abdruck von insgesamt 71 Liedern, u.a.: 'Was ist des Deutschen Vaterland?'. 'Freiheit, die ich meine', 'Der Gott, der Eisen wachsen ließ', 'Frisch auf, mein Volk!', 'Stimmt an mit hellem, hohem Klang' und 'Schleswig-Holstein, meerumschlungen'

Radiation dose reduction in postoperative computed position control of cochlear implant electrodes in lambs - An experimental study

OBJECTIVE Cochlear implants (CI) are standard treatment for prelingually deafened children and postlingually deafened adults. Computed tomography (CT) is the standard method for postoperative imaging of the electrode position. CT scans accurately reflect electrode depth and position, which is essential prior to use. However, routine CT examinations expose patients to radiation, which is especially problematic in children. We examined whether new CT protocols could reduce radiation doses while preserving diagnostic accuracy. METHODS To investigate whether electrode position can be assessed by low-dose CT protocols, a cadaveric lamb model was used because the inner ear morphology is similar to humans. The scans were performed at various volumetric CT dose-indexes CTDIvol)/kV combinations. For each constant CTDIvol the tube voltage was varied (i.e., 80, 100, 120 and 140kV). This procedure was repeated at different CTDIvol values (21mGy, 11mGy, 5.5mGy, 2.8mGy and 1.8mGy). To keep the CTDIvol constant at different tube voltages, the tube current values were adjusted. Independent evaluations of the images were performed by two experienced and blinded neuroradiologists. The criteria diagnostic usefulness, image quality and artifacts (scaled 1-4) were assessed in 14 cochlear-implanted cadaveric lamb heads with variable tube voltages. RESULTS Results showed that the standard CT dose could be substantially reduced without sacrificing diagnostic accuracy of electrode position. The assessment of the CI electrode position was feasible in almost all cases up to a CTDIvol of 2-3mGy. The number of artifacts did not increase for images within this dose range as compared to higher dosages. The extent of the artifacts caused by the implanted metal-containing CI electrode does not depend on the radiation dose and is not perceptibly influenced by changes in the tube voltage. Summarizing the evaluation of the CI electrode position is possible even at a very low radiation dose. CONCLUSIONS CT imaging of the temporal bone for postoperative electrode position control of the CI is possible with a very low and significantly radiation dose. The tube current-time product and voltage can be reduced by 50% without increasing artifacts. Low-dose postoperative CT scans are sufficient for localizing the CI electrode.

Characterization of the Capacitance of a Rotating Ring–Disk Electrode

The use of rotating ring–disk electrodes as generator-collector systems has so far been limited to the detection of Faradaic currents at the ring. As opposed to other generator-collector configurations, non-Faradaic detection has not yet been carried out with rotating ring–disk electrodes. In this study, a.c. perturbation based detection for measurement of the ring impedance is introduced. By using a conducting polymer-modified disk electrode in combination with a bare gold ring as a model, it is shown that the measured ring capacitance correlates with the polarization of the polymer film, most probably due to counter-ion exchange. A method of calculating the ring capacitance based on a small-signal sinusoid perturbation is described and the most important instrumental limitations are identified.

Open radical cystectomy: still the gold standard for muscle invasive bladder cancer

INTRODUCTION Muscle invasive bladder cancer is an unforgiving disease, and if untreated, it leads to death within 2 years of the diagnosis in >85 % of the patients. Long-term oncologic efficacy remains the ultimate standard that all procedures have to be measured by. In the past decades, open radical cystectomy (RC), extended pelvic lymph node dissection (PLND), and urinary diversion have been established as the gold standard. In the last few years, however, growing attention has been set on robotic-assisted radical cystectomy (RARC). RESULTS Even in the very long term, open RC has good oncological results and if an ileal neobladder is performed excellent functional results. Follow-up of patients after open RC exceeds more than a decade which is unsurpassed by any other technique. Its outcomes have been proven to be durable and cost-effective. Least perioperative complications as well as best oncological and functional results can be achieved if open RC and urinary diversion were performed in a high-volume hospital by high-volume surgeons and an experienced team. CONCLUSIONS Despite upcoming new technologies such as RARC, open RC following extended (PLND) remains the gold standard treatment for high-grade muscle invasive bladder cancer.

Fief la Repoplik! Weg mit det Gold und schwarzen Doot! Wir Pulletarier woll'n blos roth ...

Welsch (Projektbearbeiter): Spottgedicht auf die republikanischen Agitatoren und ihre Anhänger

Complications with computer-aided designed/computer-assisted manufactured titanium and soldered gold bars for mandibular implant-overdentures: short-term observations

BACKGROUND Implant-overdentures supported by rigid bars provide stability in the edentulous atrophic mandible. However, fractures of solder joints and matrices, and loosening of screws and matrices were observed with soldered gold bars (G-bars). Computer-aided designed/computer-assisted manufactured (CAD/CAM) titanium bars (Ti-bars) may reduce technical complications due to enhanced material quality. PURPOSE To compare prosthetic-technical maintenance service of mandibular implant-overdentures supported by CAD/CAM Ti-bar and soldered G-bar. MATERIALS AND METHODS Edentulous patients were consecutively admitted for implant-prosthodontic treatment with a maxillary complete denture and a mandibular implant-overdenture connected to a rigid G-bar or Ti-bar. Maintenance service and problems with the implant-retention device complex and the prosthesis were recorded during minimally 3-4 years. Annual peri-implant crestal bone level changes (ΔBIC) were radiographically assessed. RESULTS Data of 213 edentulous patients (mean age 68 ± 10 years), who had received a total of 477 tapered implants, were available. Ti-bar and G-bar comprised 101 and 112 patients with 231 and 246 implants, respectively. Ti-bar mostly exhibited distal bar extensions (96%) compared to 34% of G-bar (p < .001). Fracture rate of bars extensions (4.7% vs 14.8%, p < .001) and matrices (1% vs 13%, p < .001) was lower for Ti-bar. Matrices activation was required 2.4× less often in Ti-bar. ΔBIC remained stable for both groups. CONCLUSIONS Implant overdentures supported by soldered gold bars or milled CAD/CAM Ti-bars are a successful treatment modality but require regular maintenance service. These short-term observations support the hypothesis that CAD/CAM Ti-bars reduce technical complications. Fracture location indicated that the titanium thickness around the screw-access hole should be increased.

Michael Gold, Juden ohne Geld [Rezension]

Shalom Ben-Chorin

Deformation Studies of Tungsten-Gold Contacts at the Nanometer Scale.

The deformation behavior of atomically clean, nanometer sized tungsten / gold contacts was studied at room temperature in ultra-high vacuum. An instrument that combines atomic force microscopy (AFM), scanning tunneling microscopy (STM), and field ion microscopy (FIM) into a single experimental apparatus was designed, constructed, and calibrated. A cross-hair force sensor having a spring constant of - 442 N/m was developed and its motion was monitored during indentation experiments with a differential interferometer. Tungsten tips of controlled size (12.8 nm < tip radius < 2 1.6 nm) were first shaped and characterized using FIM and then indented into a Au (1 10) single crystal to depths ranging from 1.5 nrn to 18 nm using the force sensor. Continuum mechanics models were found to be valid in predicting elastic deformation during initial contact and plastic zone depths despite our small size regime. Multiple discrete yielding events lasting < 1.5 ms were observed during the plastic deformation regime; at the yield points a maximum value for the principal shear stress was measured to be 5 + 1 GPa. During tip withdrawal, "pop-out" events relating to material relaxation within the contact were observed. Adhesion between the tip and sample led to experimental signatures that suggest neck formation prior to the break of contact. STM images of indentation holes revealed various shapes that can be attributed to the (1 1 1 ) (1 10) crystallographic slip system in gold. FIM images of the tip after indentation showed no evidence of tip damage

Did Impending War in Europe Help Destroy the Gold Bloc in 1936? An Internal Inconsistency Hypothesis

This paper investigates the gold bloc operated between France, the Netherlands, Switzerland and Belgium, especially over the period after the USA left the gold standard in March 1933 to its end in September 1936. It enquires into the effect of military-political developments in Germany and Italy on the sustainability of the gold bloc between its members. Juxtaposed is the view of leading political scientists, such as Henry Kissinger, who see impending war in Europe as deeply and adversely affecting psychology in Europe, and what may be called the standard "economists' view" that sees the demise of the gold bloc as being caused almost exclusively by economic factors. Developing concepts of external and internal inconsistency of the gold bloc, this investigation concludes that both economic and military-political developments played important roles in destroying the last vestiges of the gold standard.

Die Gold- und Silberfarne unserer Gewächshäuser

Vom Professor Dr. Karl Koch