With I figure and 2 tables Zusammenfassung Die ,,IUGS Subeommission on the Systematics of Igneous Rocks" unterbreitet hier ihre Empfehlungen ffir die Benennung und Klassifizierung pyroklastischer sowie gemischt pyroklastiseh-epiklastischer Ablagerungen auf Grund deskriptiver, haupts~ichlich granulometrischer, Kriterien. Diese Empfehlungen sind das l~esultat einer internationalen Umfrage mittels Fragebogen, die sida iiber die letzten vier Jahre erstreckte. AbstractThe IUGS Subcommission on the Systematics of Igneous Rocks herein presents its recommendations on the nomenclature and classification of pyroclastic and mixed pyroclastic-epiclastic deposits using descriptive, mainly granulometric, criteria. The recommendations are the result of an international inquiry by means of questionnaires during the last four years. Rasum~La ~Subcommission on the Systematics of Igneous Rocks,< de I'IUGS pr6sente ici ses recommendations pour la d6nomination et la classification des roches pyroclastiques et pyroelastiques-6piclastiques selon arguments descriptives, surtout granulom6triques. Ces recommendations repr6sentent le r6sultat d'une enqu~te internationale ex6cut6e pendant les quatres ann6es pass6es. I~paTEoe Co~cp~aHHeMe~yHapo~Haa KOMMHCCHH no CHCTeMaTHKe 3pyHTHBHbIX nopo~, a TaI~e Hx COCTaBHBIX HaCTef~ --,,IUGS" -npe~aomHaa aSKeTy. 3~ecr~ rIpHBO~TCH pesyJn~-raTbI onpoca ~ npe~aoa~eHx~a, ~aK oT~ea~ris~x y~eHbix, Tare r~ ynpem~enrxf~ o ~aaccr~qb~Ka~Hr~ 3py~TX~BHt,lX nopo~.

The expansion of renewable energy and the growing number of electric vehicles and mobile devices are demanding improved and low-cost electrochemical energy storage. In order to meet the future needs for energy storage, novel material systems with high energy densities, readily available raw materials, and safety are required. Currently, lithium and lead mainly dominate the battery market, but apart from cobalt and phosphorous, lithium may show substantial supply challenges prospectively, as well. Therefore, the search for new chemistries will become increasingly important in the future, to diversify battery technologies. But which materials seem promising? Using a selection algorithm for the evaluation of suitable materials, the concept of a rechargeable, high-valent all-solid-state aluminum-ion battery appears promising, in which metallic aluminum is used as the negative electrode. On the one hand, this offers the advantage of a volumetric capacity four times higher (theoretically) compared to lithium analog. On the other hand, aluminum is the most abundant metal in the earth's crust. There is a mature industry and recycling infrastructure, making aluminum very cost efficient. This would make the aluminum-ion battery an important contribution to the energy transition process, which has already started globally. So far, it has not been possible to exploit this technological potential, as suitable positive electrodes and electrolyte materials are still lacking. The discovery of inorganic materials with high aluminum-ion mobility—usable as solid electrolytes or intercalation electrodes—is an innovative and required leap forward in the field of rechargeable high-valent ion batteries. In this review article, the constraints for a sustainable and seminal battery chemistry are described, and we present an assessment of the chemical elements in terms of negative electrodes, comprehensively motivate utilizing aluminum, categorize the aluminum battery field, critically review the existing positive electrodes and solid electrolytes, present a promising path for the accelerated development of novel materials and address problems of scientific communication in this field.

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We consider the classic problem of pole placement by state feedback. We adapt the Moore eigenstructure assignment algorithm to obtain a novel parametric form for the pole-placing gain matrix, and introduce an unconstrained nonlinear optimization algorithm to obtain a gain matrix that will deliver robust pole placement. Numerical experiments indicate the algorithm's performance compares favorably against several other notable robust pole placement methods from the literature.

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Endothelins (ETs), peptides that were originally isolated from endothelial cells, have extremely potent and long-lasting vasoconstricting effects on cerebral vessels in vitro and in vivo. Observations that astrocytes produce these peptides and that their ET production can be stimulated, e.g. by thrombin, and potentiated via a self-enhancing autoregulatory mechanism may have shed new light upon the pathogenesis of cerebrovasospasm (CVS). ETs are present at low levels in normal human cerebrospinal fluid (CSF). Few and contradictory reports exist on ET levels in subarachnoid hemorrhage (SAH)-associated CVS. We monitored ventricular CSF, plasma, and 24-h urine levels of immunoreactive endothelin-1 (ET-1) and endothelin-3 (ET-3) in seven patients with SAH, who did (five) or did not (two) develop CVS in the course of their disease, as well as in two patients with different conditions (acoustic neuroma/postoperative meningitis; hydro-/hematocephalus) over 7-19 days. A distinct peak of both ET-1 and ET-3 in CSF of patients with SAH coincided with clinically documented signs of CVS and was absent in CSF of patients with SAH but no CVS. CSF levels of ET-1 and ET-3 displayed a striking parallelism in all subjects. Plasma ET-1 levels were essentially in the normal range. ET-3 was not detectable in plasma under our assay conditions. The excretion profiles of ET-1 and ET-3 in 24-h urine revealed again a predominantly parallel behavior of the two peptides. Interestingly, patients with high ET levels in CSF showed simultaneous peaks in urinary ET excretion, expressed as nanograms per gram of creatinine. Our findings support an association of ETs with the pathogenic events following SAH. The well-documented effects of these peptides on cerebral vessels suggest they are mediators rather than markers of disease.

This paper describes the analysis and design of saturated silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) switches for millimeter-wave applications. A switch optimization procedure is developed based on detailed theoretical analysis and is then used to design multiple switch variants. The switches utilize IBM's 90-nm 9HP technology, which features SiGe HBTs with peak of 300/350 GHz. Using a reverse-saturated configuration, a single-pole double-throw switch with a measured insertion loss of 1.05 dB and isolation of 22 dB is achieved at 94 GHz after de-embedding pad losses. The switch draws 5.2 mA from a 1.1-V supply, limiting power consumption to less than 6 mW. The switching speed is analyzed and the simulated turn-on and turn-off times are found to be less than 200 ps. A technique is also introduced to significantly increase the power-handling capabilities of saturated SiGe switches up to an input-referred 1-dB compression point of 22 dBm. Finally, the impact of RF stress on this novel configuration is investigated and initial measurements over a 48-h period show little performance degradation. These results demonstrate that SiGe-based switches may provide significant benefits to millimeter-wave systems.Index Terms-Millimeter wave, 94 GHz, reverse saturation, saturation, silicon-germanium (SiGe) heterojunction bipolar transistor (HBT), single-pole double throw (SPDT), switch, transformer.