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Fibrous phosphorus is prepared by controlled heating of red phosphorus (evacuated silica tube, 1.

[Cd3Cu]CuP10, a polyphosphide containing adamantine-analogue [P10] unit undergoes a solid-state polymerization to form [P6] rings and tubular [P26] polymer units at elevated temperatures. This reaction represents the rare case of a polyphosphide polymerization in the solid state. The formation of such a polymeric unit starting from a molecular precursor is the first evidence of the general possibility to perform a bottom-up route to the well-known tubular polyphosphide units of elemental phosphorus in a solid material. Temperature-dependent X-ray powder diffraction experiments substantiate the solid phase transformation of [Cd3Cu]CuP10 starting at 550 °C to the polymerized form via an additional intermediate step. A single crystal structure determination of the quenched product at room temperature was performed to evaluate the structural properties and the resulting polyphosphide units. The full polymerization and decomposition mechanism has been analyzed by thermogravimetric experiments and subsequent X-ray powder phase analyses. The present [P26] polymer unit represents a former unseen one-dimensional cut-out of the two-dimensional polyphosphide substructure of Ag3P11 and can be directly related to the tubular polyphosphide substructures of violet or fibrous phosphorus.

The pure ternary phases on the line Sm2O3-SeO2: Sm2SexO3+2x in thermodynamical equilibri­um have been synthesizied by solid state reactions and characterized by X-ray powder diffrac­tion, IR spectroscopy and DSC measurements. The existence of two new phases Sm2Se1,5O6 and Sm2Se4O11 was demonstrated besides the known phases Sm2Se3,5O10, Sm2Se3O9 and Sm2SeO5. The thermal decomposition properties of all compounds have been determined by total pressure measurements and the thermodynamical data of the compounds have been derived from their decomposition function and Cp-values. The phase diagram and the phase barogram have been estabilished using the results of DSC and total pressure measurements.

Auf dem quasibinaren Schnitt BiOCl/SeO2 wurde die Existenz nur einer ternaren Verbindung BiOCl · SeO2 = BiSeO3Cl nachgewiesen. Durch Gesamtdruckmessungen und DTA wurden das Zustandsbarogramm und das Zustandsdiagramm des Systems aufgestellt. Die bei Raumtemperatur stabile Phase α-BiSeO3Cl weist eine stark endotherme Umwandlung (α β) bei 400 ± 2 °C und eine schwach endotherme Umwandlung (β γ) bei 410 ± 3 °C auf; die Verbindung schmilzt peritektisch bei 417 ± 3 °C. Aus dem chemischen Transport von BiOClf mit SeO2,g und der Wanderung von BiSeO3Clf im Temperaturgefalle folgt die Existenz der Gasspezies BiSeO3Cl. In Auswertung des Zersetzungsdruckes von BiSeO3Clf, des Sattigungsdruckes und des chemischen Transportes erhalt man die Standardwerte:δH°B (α-BiSeO3Clf, 298) = –148,0 ± 2,8 kcal/mol,S°(α-BiSeO3Clf, 298) = 41,0 ± 2,0 cal/mol K undδH°B(BiSeO3Clg, 298) = –102,7 ± 7,0 kcal/mol,S°(BiSeO3Clg, 298) = 101,0 ± 5,0 cal/mol K.Durch Losungskalorimetrie in 4 n HCl wurden hergeleitet:δH°B(α-BiSeO3Clf, 298) = –148,5 ± 1,4 kcal/mol undδH°B(β-BiSeO3Clf, 298) = –148,2 ± 1,4 kcal/mol Investigations on the System BiOCl/SeO2 The section BiOCl/SeO2 was shown to be quasibinary one and include only one intermediate phase BiOCl · SeO2 = BiSeO3Cl. The phase barogram and the phase diagram were determined by total pressure measurements and DTA. BiSeO3Cl shows on heating two transitions in crystal phase, (α β) at 400 ± 2 °C and (β γ) at 410 ± 3 °C. The compound melts peritectically at 417 ± 3 °C. The experiments on sublimation of BiSeO3Cl in the temperature gradient and chemical vapour transport with SeO2 allowed to make the conclusion on the existence of BiSeO3Cl molecules in the vapour. Some standard thermodynamic data were determined by solution calorimetry and evaluated from the vapour pressure and chemical vapour transport rate data. (Data see Inhaltsubersicht)

Glucocorticoid hormones influence manifold neuronal processes including learning, memory, and emotion via the glucocorticoid receptor (GR). Catecholamines further modulate these functions, although the underlying molecular mechanisms are poorly understood. Here, we show that epinephrine and norepinephrine potentiate ligand-dependent GR transactivation in a hippocampal cell line (HT22) via beta(2)-adrenergic receptors. This enhancement was strongest at low concentrations of glucocorticoids and was accompanied by increased GR binding to a glucocorticoid-responsive element (GRE). beta(2)-Adrenergic receptor-mediated GR enhancement was relayed via G protein beta gamma-subunits, insensitive to pertussis toxin and independent of protein kinase A (PKA). In contrast, the catecholamine-evoked GR enhancement was strongly reduced by wortmannin, suggesting a critical role for phosphoinositide 3-kinase (PI3-K). In agreement, epinephrine directly activated PI3-K in vivo. Similarly, stimulation of tyrosine kinase receptors coupled to PI3-K activation, e.g. receptors for insulin-like growth factor I (IGF-I) or fibroblast growth factor (FGF), increased GR transactivation. Further analysis indicated that G protein-coupled receptor (GPCR) and tyrosine kinase receptor signals converge on PI3-K through separate mechanisms. Blockade of GR enhancement by wortmannin was partially overcome by expression of the downstream-acting protein kinase B (PKB/Akt). Collectively, our findings demonstrate that GPCRs can regulate GR transactivation by stimulating PI3-K. This novel cross-talk may provide new insights into the molecular processes of learning and memory and the treatment of stress-related disorders.

Durch Gesamtdruckmessungen uber Bodenkorper und auserhalb des Sattigungsbereiches wurde das Verdampfungs-, bzw. Zersetzungsverhalten Studiert. Im Zustandsbarogramm des Systems Se/Cl hat die Bodenkorperzusammensetzung Cl/Se = 4 den geringsten und Cl/Se = 2 den hochsten Gesamtdruck. Im Bodenkorper existieren als diskrete Verbindungen SeCl4,f und Se2Cl2,fl, in der Gasphase tritt nur SeCl2 auf. Aus der Zersetzungssublimation von SeCl4 und der Zersetzungsreaktion von Se2Cl2 folgen die Daten ΔH(SeCl2,g,298) = −29,8 kJ/mol und S°(Se2Cl2,fl,298) = 247 J/K · mol. Fur die Verdampfung von SeOCl2 gelten ΔH°(verd, SeOCl2,298) = 55,0 kJ/mol und S°(verd. SeOCl2,298) = 126,5 J/K · mol. Aus der Zersetzungsreaktion des gasformigen SeOCl2 wird die Bildungsenthalpie ΔH(SeOCl2,g,298) = −128,0 kJ/mol abgeleitet. Equilibrium Measurements in the System Se/O/Cl The evaporation and decomposition behaviour was Studied by total pressure measurements in equilibrium with condensed phases as well as in the unsaturated Vapour. The composition Cl/Se = 4 shows the lowest, the composition Cl/Se = 2 the highest total pressure in the Barogramm of the system Se/Cl. Solid SeCl4 and liquid Se2Cl2 exist as condensed compounds whereas only SeCl2 exists in the gas. The following data were derived (see „Inhaltsubersicht”) from the decomposition sublimation SeCl4, the decomposition of Se2Cl2 and the evaporation and decomposition of SeOCl2.

Heat treatment of solid [Cd3Cu]CuP10 in evacuated silica ampules at 500 °C for 4 d leads to the formation of Cd15Cu10P46, which contains [P6] rings and tubular [P26] polymer units.

Die Existenz der Verbindungen Bi4O4SeCl2, Bi10O12SeCl4 und Bi22O28SeCl8 im System Bi2O3/Bi2Se3/BiCl3 wurde durch Festkorperreaktionen und Chemischen Transport nachgewiesen. Daruber hinaus wurden die Festkorper-Gasphasengleichgewichte fur die Verbindungen massenspektrometrisch untersucht. Dabei wurde die Gasspezies BiSeCl erstmals experimentell nachgewiesen und ihre Geometrie und thermochemischen Eigenschaften uber ab-initio Molekulberechnungen charakterisiert. Weiterfuhrende thermodynamische Modellierungen der heterogenen Gleichgewichte unterstutzen das Verstandnis der experimentellen Ergebnisse zur Gasphasenzusammensetzung sowie zum Chemischen Transport. Gas-Phase Equilibria of Quaternary Bismuth Selenium Oxidechlorides The existence of new compounds Bi4O4SeCl2, Bi10O12SeCl4, and Bi22O28SeCl8 in the pseudoternary area Bi2O3/Bi2Se3/BiCl3 has been established by solid state and chemical vapour transport reactions. Furthermore, heterogeneous equilibria between solid state and vapour phase have been studied by mass-spectrometric measurements. The novel gas-molecule BiSeCl has been detected. The results of ab initio calculations for structure and refining of thermochemistry of this molecule are given: (Bi–Se) = 2,44 A; (Bi–Cl) = 2,49 A; (Se–Bi–Cl) = 106,0°; Thermodynamics: δH°B,298 (BiSeClg) = 6,0 kcal/mol; S°298 (BiSeClg) = 75,8 cal/mol K; Cp (BiSeClg) = 13,583 + 0,64 · 10–3 · T – 0,41 · 105 · T–2 – 0,35 · 10–6 · T2 cal/mol K. Finally, the composition of the gaseous phase has been calculated and estimations about chemical vapour transport were carried out by thermodynamic modelling.

Pituitary adenylate cyclase-activating polypeptides and PAC1-R are expressed during early embryogenesis and PACAP's neurotrophic action supports a role in neuronal development. In the adult brain PACAP functions as a neuroprotective factor that attenuates the neuronal damage resulting from various insults. The tumor suppressor gene p53 and the new zinc finger protein Zac regulate apoptosis and cell cycle arrest through unrelated pathways and both genes are up-regulated under cerebral ischemia. We report here that p53 and Zac induce expression of the PAC1-R gene. By this mechanism p53 and Zac could fine-tune the balance between death promoting and protective signals and may thus fulfil a dual role in ischemia.

We describe the existence of six thermodynamically stable phases on the binary line Bi2O3- SeO2 at room temperature: Bi12SeO20, Bi10Se2O19, Bi16Se5O34, Bi2SeO5, Bi2Se3O9 and Bi2Se4O11. At higher temperature we optained evidence for Bi20Se3O36 and Bi4SeO8. The decomposition pressures were measured for all phases in a membrane zero manometer and the enthalpy of formation and the standard entropy was determined. The phase barogram and phase diagram followed from total pressure measurements and differential thermoanalysis. The standard enthalpies of formation of all phases were also derived from solution calorimetry. The necessary data of transitions on molar enthalpies were obtained by DSC- and Cp-measurements.

The phase relations in the ternary system Bi/Te/O have been determined in previous studies by solid state reactions. Thermodynamical data have now been obtained for the pertinent equilibria. The heats of solution of Bi2O3, Bi12TeO20, Bi10Te2O19, Bi16Te5O34, Bi2TeO5, Bi2Te2O7, Bi2Te4O11 and TeCl4 were determined in 4N HCl. From these the enthalpies of formation of bismuth tellurites at 298 K have been derived: ⊿H°b (Bi12TeO20, f, 298) = -901,6 ± 8 kcal/mol, ⊿H°b (Bi10Te2O19, f, 298) = -856,1 ± 9 kcal/mol, ⊿H°b (Bi16Te5O34, f, 298) = -1519,5 ± 17 kcal/mol, ⊿H°b (Bi2TeO5, f, 298)= -222,8 ± 3 kcal/mol, ⊿H°b (Bi2Te2O7, f, 298)= -299,4 ± 4 kcal/mol, ⊿H°b (Bi2Te4O11, f, 298)= -448,2 ± 7 kcal/mol.

Only the ternary phase Bi2O2Se is shown to exists in the thermodynamical equilibrium in the investigated ternary system on the binary line Bi2O3-Bi2Se3. Its thermal decomposition was measured in a quartz membrane zero manometer. The enthalpy of formation and the standard entropy were derived from the temperature function of the decomposition equilibrium: ⊿H°f(Bi2O2Ses,298) = -104,6 ±4,0 kcal/mol S°(Bi2O2Ses,298) = 43 ± 3 cal/K·mol. The coexistence ranges in the ternary region Bi2O3- SeO2- Bi2O2Se-Se were followed by X-ray diffraction, IR spectroscopy and total pressure measurements of binary and ternary compositions.

Since their first recognition in mineral forming processes some 150 years ago chemical vapor transport reactions (CVTR) have attracted continuous scientific interest. Due to the pioneering work of Harald Schafer quantitative understanding and exploitation of transport reactions for crystal growth, synthesis, investigation of high-temperature gas species, and thermodynamic studies have become possible. Renewed interest in CVT is triggered by the demand of material sciences for novel compounds with tailor-made physical properties and by the need for efficient recycling strategies for various metals from industrial waste.

In Kapitel A wurden der Jahresabschluss und die bei seiner Aufstellung zu beachtenden Grundsatze diskutiert. Um im Detail zu sehen, wie die einzelnen Komponenten des Jahresabschlusses (insbesondere Bilanz und Gewinn- und Verlustrechnung) entstehen, werden Sie in diesem Kapitel in die allgemeine Buchfuhrungstechnik eingefuhrt.

In diesem Kapitel wird naher auf eine Reihe ausgewahlter Buchungsvorgange eingegangen, die im Laufe eines Geschaftsjahres in einem Industriebetrieb regelmasig anfallen konnen.

Chemical Vapor Transport Reactions–Methods, Materials, Modeling

The title compound, the first intermetallic compound in the Cu—Cd—As system, is synthesized by solid state reaction of a stoichiometric mixture of the elements (1000 °C, 63 h) and characterized by powder and single crystal XRD, DFT electronic structure calculations, and magnetic measurements.

This comprehensive handbook covers the diverse aspects of chemical vapor transport reactions from basic research to important practical applications. The book begins with an overview of models for chemical vapor transport reactions and then proceeds to treat the specific chemical transport reactions for the elements, halides, oxides, sulfides, selenides, tellurides, pnictides, among others. Aspects of transport from intermetallic phases, the stability of gas particles, thermodynamic data, modeling software and laboratory techniques are also covered. Selected experiments using chemical vapor transport reactions round out the work, making this book a useful reference for researchers and instructors in solid state and inorganic chemistry.

Neben dem Anlagevermogen ist auch das Umlaufvermogen zum Bilanzsichtag zu bewerten. Zu letzterem gehoren alle Vermogensgegenstande, die nicht zum Anlagevermogen, d. h. die dem Geschaftsbetrieb nicht dauerhaft dienen, und nicht zu den Rechnungsabgrenzungsposten (vgl. Abschnitt D 4) zahlen. Der Fokus dieses Kapitels liegt auf der Bewertung von Vorraten (Abschnitt D 3.2), Forderungen (Abschnitt D 3.3) und Wertpapieren des Umlaufvermogens (Abschnitt D 3.4).

Es ware auserst umstandlich und zeitraubend, nach jedem Geschaftsvorfall eine neue Bilanz zu erstellen, die den aktuellen Stand des Vermogens und der Schulden aufweist. Daher wird die Bilanz zu Beginn eines jeden Geschaftsjahres (Eroffnungsbilanz) in einzelne Rechnungsstellen, sog. Konten, aufgeteilt, auf denen dann im Verlauf des Geschaftsjahres die Verbuchungen der Geschaftsvorfalle erfolgen. Fur jeden Bilanzposten existiert also ein eigenes Konto. Zum Jahresende werden diese dann wieder zu einer Schlussbilanz zusammengefasst.

Back in black: All metastable and stable phases can be identified for the solid solution arsenic/phosphorus by a combination of quantum-chemical calculations and investigations of the phase formation. Reaction paths for phase formations and transitions in situ were also evaluated. The results show that orthorhombic black arsenic (o-As) is metastable in pure form and has only been previously obtained by stabilizing impurities.