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BACKGROUND: β-lactoglobulin (BLG) stimulates muscle protein synthesis and β-hydroxybutyrate (BHB) inhibits muscle breakdown. Whether combining the 2 can additively attenuate disease-induced muscle loss is unknown.OBJECTIVE: Based on previous observations of anticatabolic effects of protein and ketone bodies during inflammation, and using a novel model combining ongoing systemic inflammation, fasting, and immobilization, we tested whether the anticatabolic muscle response to oral amino acids is altered compared with control conditions, as well as whether coadministration of oral BHB and BLG further improves the muscle anabolic response. Muscle net balance (NBphe) was the primary outcome and intramyocellular signals were assessed.METHODS: In a randomized crossover design, 8 young men underwent either preconditioning with LPS (prestudy day: 1 ng/kg, study day: 0.5 ng/kg) combined with a 36-h fast and bed rest to mimic catabolic inflammatory disease (CAT) or an overnight fast (control [CTR]) prior to isocaloric nutritional interventions on 3 occasions separated by ∼6 wk (range 42 to 83 d).RESULTS: NBphe increased similarly upon all conditions (interaction P = 0.65). From comparable baseline rates, both Rdphe [muscle synthesis, median ratio (95% CI): 0.44 (0.23, 0.86) P = 0.017] and Raphe [muscle breakdown, median ratio (95% CI): 0.46 (0.27, 0.78) P = 0.005] decreased following BHB + BLG compared with BLG. BLG increased Rdphe more under CAT conditions compared with CTR (interaction P = 0.02). CAT increased inflammation, energy expenditure, and lipid oxidation and decreased Rdphe and anabolic signaling [mammalian target of rapamycin (mTOR) and eukaryotic translation initiation factor 4E-binding protein 1 (4EPB1) phosphorylation].CONCLUSION: In contrast to our initial hypothesis, NBphe increased similarly following BLG during CAT and CTR conditions; CAT however, specifically stimulated the BLG-mediated increase in protein synthesis, whereas BHB coadministration did not affect NBphe, but distinctly dampened the BLG-induced increase in muscle amino acid fluxes thereby liberating circulating amino acids for anabolic actions elsewhere.

Some aspects of the CubeMAP mission (also known as ESP-MACCS) are presented: its science objectives, and the primary choices made to address them from small satellite platforms. The science case, addressing some key scientific questions related to global change, is elaborated in four objectives focused on upper troposphere and stratospheric composition and its change. The sounding methodology and the associated observation concept retained is a constellation of miniature limb solar occultation thermal infrared sounders, offering the advantages of limb solar occultation, whilst mitigating the inherent lack of coverage of this geometry. The mission focuses on tropical regions as the gateway to the upper troposphere, and the stratosphere. The miniaturized instrument payloads developed for the mission are briefly presented: the High resolution InfraRed Occultation Spectrometer (HIROS) and the Hyperspectral Solar Disk Imager (HSDI). Lastly, the nanosatellite 12U platform and its subsystem are described, completing the overview of the mission space segment.

Background: Patients' difficulties following critical illness and the willingness of intensive care units (ICU) to take an expanded responsibility during the recovery period have led to the development of different follow-up programs. The aim of this study was to explore and describe patients' participation in and evaluation of a follow-up program at a nurse-led clinic (NLC). Methods: Patients with a length of stay ≥72 h, discharged from the ICU, participated in a follow-up program based on three contacts, as a visit to the NLC, telephone contact, ward visit or as an indirect contact, during a 6-month period. A specially developed database recorded information regarding patients' participation and questionnaires were used to obtain patients' views of the follow-up program. Results: Of 96 study patients, 51% visited the NLC once or twice. These patients were younger (P

Shrimp (Pandalus borealis) from a commercial freezer trawler were thawed then subjected to different treatments (conditioning) in 20 kg lots by holding them in ice, water and brine of various salt concentrations before being steam-cooked and peeled. Various parameters such as pH, peelability, yield, salt content, dry matter, and water holding capacity were measured. Near infrared (NIR) spectra were obtained, on samples of whole shrimp and of minced flesh from the various treatments. Analysis of the spectral and compositional, treatment and processing data using principal components and partial least squares indicated that NIR could be used to distinguish between frozen and thawed material, between salt content, pH in the flesh, cooking period (temperature) of either whole or minced shrimp, or both. The NIR data could not be used to determine peelability, water holding capacity, dry matter or salt content in either whole or minced shrimp.

Die Strukturen der untersuchten Silbersilicate werden von anionischen Gittern bestimmt, innerhalb derer den Ag+-Ionen Raum fur ihre Wanderung und damit fur den Transport elektrischer Ladung zur Verfugung steht. Diesen Transport behindern vornehmlich die Korngrenzen, was sich mit Hilfe der Impedanzspektroskopie anhand der kapazitiven Anteile der Impedanz nachweisen last. On Relations between Structural and Electrochemical Properties of Various Silver Silicates The structures of the explored silver silicates are dominated by anionic lattice, within the Ag+ iones are able to move and transport electrical charge. This transport is disturbed mainly by the grain boundaries. Impedance spectroscopic measurements verify this matter because of the capacitance related to the single spectra.

The aggregation properties of zinc-free insulin have been studied using static and dynamic light scattering. The aggregation has been investigated as a function of three parameters, the concentration of sodium chloride (in the range 10-100 mM), the pH value (in the range pH 7.5-10.5), and the insulin concentration (1.8-13.4 mg/mL). The measured homodyne autocorrelation function was used to determine the apparent mean hydrodynamic diameter as well as the apparent weight-averaged molar mass of the insulin species in solution. A method of data analysis was employed, which allows the separation of light scattering contributions from the insulin oligomers and from irrelevant macromolecules and possible impurities present in the sample solutions. Also, a simple phenomenological equilibrium model describing the association of oligomers of insulin is presented. One aspect of this model is that it makes it possible to determine weight average molar masses corrected for virial effects on the Rayleigh ratio. This was necessary because virial effects cannot be isolated and corrected for by dilution since this would change the equilibrium distribution of oligomers. The basis of the model is a positive contribution to Gibbs free energy from charge repulsion depending on the protein charge and the number of monomers in the oligomers, and an assumed constant negative contribution to Gibbs free energy arising from either an entropic gain or hydrogen bonding upon association. The equilibrium model gives a good description of both the apparent weight average molar masses and the apparent hydrodynamic diameters, when the effect of the insulin concentration is taken into account by including virial effects arising from charge-charge repulsion (Donnan effect). The result shows that the association of insulin as a function of pH and ionic strength can be described by an effective charge equal to the charge derived from proton titration reduced by the number of sodium ions binding to insulin. At the lowest pH and highest salt concentration (pH 7.5, 100 mM NaCl, 12 mg/mL insulin), the weight average molar mass is close to that of the hexamer, and at the highest pH and lowest salt concentration (pH 10.5, 10 mM NaCl, 1.9 mg/mL), the weight average molar mass is close to that of the monomer. In all cases, however, a distribution of oligomers is present with a relative Gaussian width of about 30%.(ABSTRACT TRUNCATED AT 400 WORDS)

A high transport critical current density, J c , in Ag-sheathed Bi-2223 superconducting tapes had been obtained using the oxide powder-in-tube technique. At 77 K and self-field, the highest J c value of 69 000 A/cm 2 was measured for tapes of 80 μm thickness ( I c =35 A), while the largest critical current, I c , reached 74 A for tapes of 150 μm thickness ( J c =61 000 A/cm 2 ). A detailed investigation of the processing parameters has been carried out on the phase content and particle size of the starting powders, and on the sintering treatment and mechanical deformation of the tapes.

The structures of the Ag–Ge-zeolite Ag3HGe7O16·4H2O and its pyrolyse products Ag4Ge9O20 and Ag2Ge4O9 consist of a network of linked (GeO4)-tetraedra and (GeO6)-octahedra. In this network there exist free channels, which can be used as transport paths through the structure by Ag+-ions. Impedance spectroscopic measurements show the loss of weakly bonded water at about 210°C and irreversible structural changes, which finally lead to the pyrolysis products. Lattice vibrations prevent a better Ag+-mobility, so the high expectations concerning the conductance properties could not be fulfilled. In all cases the main part of the resistance could be attributed to the grain boundaries between the crystals.

Metall-bis(acetylacetonate) fungieren in THF gegenuber Zink(II)-chlorid als bifunktionelle Lewis-Basen und bilden binukleare Komplexe (THF)2M(acac)2ZnCl2 (M = Co, Ni, Mg). Ein oktaedrisches und ein tetraedrisches Zentrum sind uber zwei dreibindige Sauerstoffatome der Acetylacetonatliganden miteinander verknupft (Bildung eines viergliedrigen MOZnO-Rings). Die Addition ist mit einer Deformation des oktaedrischen Zentrums verbunden, die eine dichte Packung der vier Atome des MOZnO-Ringes ermoglicht. Gegenuber Quecksilber(II)-chlorid fungieren die Metall-bis(acetylacetonate) als tetrafunktionelle Lewis-Basen. In den trinuklearen Komplexen (THF)2M(acac)2(HgCl2)2 (M = Co, Ni, Mg) bleibt die Wechselwirkung zwischen den drei Koordinationszentren gering; das oktaedrische Zentrum wird strukturell nicht verandert, die beiden HgCl2-Bausteine weichen nur gering von der Linearitat ab. Ein Ligandenaustausch wurde in folgenden Fallen beobachtet: (a) Umsetzung von Vanadium(III)-chlorid mit Co(acac)2 unter Bildung von [(THF)2V(acac)2][(THF)CoCl3] (ubergang der Acetylacetonatliganden auf das hoherwertige Zentralatom). (b) Umsetzung von Magnesiumhalogeniden mit M(acac)2 unter Bildung von (THF)2Mg(acac)2MX2 (c) Bildung von (THF)3Co(acac) (μ—Cl)ZnCl2 (V) aus Zn(acac)2 und Cobalt(II)-chlorid Im Komplex V ist das oktaedrische Zentrum am Cobalt uber ein dreibindiges Sauerstoffatom des Acetylacetonatoliganden und eine Chlorobrucke mit dem tetraedrischen Zentrum am Zink verknupft (Bildung eines viergliedrigen CoClZnO-Ringes mit dichtester Packung der Atome). Wesentliche Triebkraft fur die Umsetzung gemas c ist die Bildung der stabilen OZnCl3-Gruppierung. Fur den Ligandenaustausch gemas b ist die Stabilitat der oktaedrischen MgO6-Gruppierung und die leichte Bildung der teraedrischen Baugruppe MO2X2 bei den ubergangsmetallen masgebend. (THF)3Co(acac)(μ—Cl)HgCl2 (VI) ist isostrukturell mit V. Deutlich verschieden sind allerdings die Valenzwinkel am tetraedrischen Zentralatom, in die die terminalen Chloroliganden einbezogen sind (120,7° fur V; 143,7° fur VI). Die Kristallstruktur von (THF)3Co(acac)(μ—Cl)ZnCl2 (V) wurde durch Rontgenbeugung bestimmt: monoklin, Raumgruppe P21/n, Z = 4; a = 1 177,4(5); b = 1 628,9(4); c = 1 284,2(6) pm; β = 99,54(4)°; R = 6,71% fur 2 160 beobachtete Reflexe. Exchange of Metal Ions in the System Acetylacetonate/Halide/Tetrahydrofuran. As bifunctional Lewis bases metal bis(acetyl-acetonates) react with zinc(II) chloride under formation of binuclear complexes (THF)2M(acac)2ZnCl2 (M = Ni, Co, Mg). The octahedral and the tetrahedral centre of these compounds are connected by tridentate oxygen atoms of the two acetylacetonato ligands which are simultaneously part of a four-membered ring MOZnO. The addition is combined with a deformation of the octahedral centre, as a prerequisite of a closest package of the atoms within the MOZnO ring. With mercury(II) chloride the metal bis(acetylacetonates) react as tetrafunctional Lewis bases. In the trinuclear complexes (THF)2M(acac)2(HgCl2)2 (M = Co, Ni, Mg) the interaction between the three coordination centres is weak. No structural change of the octahedral centre (THF)2M(acac)2 is found, but the HgCl2 group diverge slightly from linearity. A ligand exchange was observed in the following cases: (a) Reaction of vanadium(III) chloride with Co(acac)2 under formation of [(THF)2V(acac)2][(THF)CoCl3] (transition of the acetylacetonato ligands to the higher valent central atom). (b) Reaction of magnesium halides with M(acac)2 and formation of (THF)3Mg(acac)2MX2 (c) Formation von (THF)3Co(acac)(μ—C1)ZnC12 (V) by the reaction of Zn(acac)2 with cobalt(l1) chloride In the complex V the octahedral ccntrc of cobalt(II) is connected with the tetrahedral centre of zinc(I1) by tridentate oxygen atom of the acetylacetonato ligand and a chloro bridge (formation of the four-membered CoClZnO cycle with a closest package of the atoms). A driving force for reaction c is the formation of the stable tetrahedral OZnCI3 group. Important for the li- gand exchange according to c is the stability of the octa- hcdral MgO6 moiety and the easy formation of the tetra- hedral MO2X2 group with a transition metal ion. (THF)3Co(acac)(μ-CI)(HgCl2) (VI) is isoslruclural with V. But there is a marked diffcrence between the bond angles of the tetrahedral central atom including the termi- nal chloro ligands (120.7° for V; 143.7° for VI). The crystal structure of (THF)3Co(acac)(μ-CI)ZnCl2 (V) was determined by X-ray diffraction: monoclinic; space group P2,/n; Z = 4; a = 1 177.4(5); b = 1628.9(4); c = 1284.2(6) pm; β = 99.54(4)°; R = 6.71 % for 2160 observed reflections.

Bis(acetylacetonate) von Magnesium(II), Cobalt(II) oder Nickel(II) addieren Dihalogenide wie FeCl2, CoCl2 oder NiBr2 (aMIIX2) unter Bildung binuklearer Komplexe (THF)2MII(acac)2(aMIIX2), in denen ein oktaedrisches und ein tetraedrisches Zentrum uber zwei dreibindige Sauerstoffatome der Acetylacetonatliganden miteinander verknupft sind (Bildung eines viergliedrigen MIIOMII-Ringes). Die Addition ist mit einer Deformation des oktaedrischen Zentrums verbunden, die eine dichte Packung der vier Atome des MIIOMII-Ringes ermoglicht. Im trinuklearen Komplex (THF)2Ni(acac)2(HgCl2)2III bleibt die Wechselwirkung zwischen den drei Koordinationszentren gering. Das oktaedrische Zentrum (THF)2Ni(acac)2 wird strukturell nicht verandert, allerdings weichen die beiden HgCl2-Bausteine (Valenzwinkel 171,1°) von der Linearitat ab. Es gelang nicht, binukleare Komplexe mit einem Zentralatom der Oxidationsstufe III im oktaedrischen Zentrum darzustellen. Ein Grund dafur ist die verringerte Donorstarke der zweizahligen Lewisbasen-Funktion im oktaedrischen Zentrum [(THF)Mn+(acac)2]n-2 fur M+3 als Zentralion. Reaktive Systeme mit zwei- und dreiwertigen Kationen weichen auf die Seite von ionischen Komplexen aus, wie die Bildung von [(THF)2V(acac)2][(THF)CoCl3] IV aus VCl3 und Co(acac)2 zeigt. Die Kristallstrukturen von (THF)2Co(acac)2CoCl2II und [(THF)2V(acac)2][(THF)CoCl3] IV wurden durch Rontgenbeugung bestimmt. II: orthorhombisch primitiv, Raumgruppe P212121, Z = 4; a = 967,4(2), b = 1453,4(3), c = 1715,9(4) pm; R = 0,049 fur 3084 beobachtete Reflexe. IV: triklin, Raumgruppe P1, Nr.2; Z = 2; a = 871,5(2), b = 930,6(3), c = 1865,6(6) pm; α = 101,70(2), b = 92,45(2), γ = 91,06(2)°; R = 0,060 fur 4221 beobachtete Reflexe. Addition of Transition Metal Dihalides to Acetylacetonates of Divalent Metal Ions Transition metal dihalides aMIIX2 (FeCl2, CoCl2 NiBr2 etc.) are added by the chelates MII(acac)2 under formation of binuclear complexes (THF)2MII(acac)2(aMIIX2). The octahedral and the tetrahedral centre of these compounds are connected by tridentate oxygen atoms of the two acetylacetonato ligands which are simultaneously included in four-membered rings (MIIOMII). The addition is combined with a deformation of the octahedral centre, as a prerequisite of a closest package of the atoms within the MIIOMII-ring. In the trinuclear complex (THF)2Ni(acac)2(HgCl2)2III the interaction between the three coordination centres is weak. No structural change of the octahedral centre (THF)2Ni(acac)2 is found, but the HgCl2-groups diverge slightly from linearity (ClHgCl 171.1°). No binuclear complexes with a central ion of the oxidation state III in the octahedral centre were obtained. One reason is the lowered donor strength of the bidentate Lewis base function of the octahedral centre [(THF)2Mn+(acac)2]n-2 with M+3 as a centralatom. Reacting systems with di- and trivalent ions prefer ionic complexes, as it is shown by the formation of [(THF)2V(acac)2][(THF)CoCl3] IV from VCl3 and Co(acac)2. The crystal structures of (THF)2Co(acac)2CoCl2II and [(THF)2V(acac)2][(THF)CoCl3] IV were determined by x-ray diffraction. II: orthorhombic-primitive; space group P212121, Z = 4; a = 967.4(2), b = 1453.4(3), c = 1715.9(4) pm; R = 0.049 for 3084 observed reflections. IV: triclinic; space group P1, Nr. 2; Z = 2; a = 871,5(2), b = 930,6(3), c = 1865,6(6) pm; α = 101,70(2), b = 92,45(2), γ = 91,06(2)°; R = 0,060 fur 4221 observed reflections.

Die Struktur von Diquecksilber(I)-bis(1,1,3, 3-tetracyanpropenid), Hg2(tcp)2, wurde durch Einkristall-Rontgenstrukturanalyse ermittelt. Die Kristalle sind monoklin, Raumgruppe P 21/n. Die Zelldimensionen sind a = 9,9193(3) A, b = 5,6912(6) A, c = 13,3806(4) A, β = 92,544(4)° und Z = 2. Die Quecksilberatome im zentrosymmetrischen Kation werden dreifach koordiniert mit HgHg 2,503; HgN 2,207; 2,560 A. tcp fungiert als zweizahniger Ligand unter Ausbildung unendlicher Ketten parallel zur a-Achse. Mercury Compounds with Cyancarbanions. II Synthesis and Crystal Structure of Dimercury(I)-bis(1,1,3,3-tetracyanpropenide) The structure of dimercury(I)-bis(1,1,3,3-tetracyanpropenide), Hg2(tcp)2, has been determined by single-crystal X-ray diffraction methods. The crystals are monoclinic, space group P 21/n. The unit cell dimensions are: a = 9.9193(3) A, b = 5.6912(6) A, c = 13.3806(4), β = 92.544(4)° and Z = 2. The mercury atoms in the centrosymmetric cation are three-coordinate with HgHg 2.503, HgN 2.207, 2.207, 2.560 A. tcp behaves as a bidentate ligand forming infinite chains running parallel to the a-axis.

Major improvements and expansion of the capabilities of the aircraft recovery systems that are now in service on our aircraft carriers are feasible with existing technology, without any major hardware design change and without jeopardizing the high reliability of the current hydraulic-mechanical arresting gear that was designed in the 1950s. A self-compensat ing (model-reference adaptive) control system with multiple redundancy and majority voting logic can be developed and installed on our aircraft carriers at a cost less than that of the first aircraft saved by such a system. Feasibility of a "Closed-Loop Control System" that eliminates the risk of aircraft losses due to an erroneous weight preset has been demonstrated by computer simulation. The installation of cable-payout transducers (encoders), of a signal processor, and a servo-actuator that can correct the mis-set of a weight adjustment lever can solve this problem. In addition, an expansion of the current design limits for off-center engagement and for weight and speed of the landing aircraft, as well as a reduction in stress levels and a corresponding increase in service life for aircraft (such as the A-6) and arresting systems, can be achieved by modifications of the cable damper subsystems that are now in service.

As thermochromic compounds, tetraiodomercurates show phase transitions, which have been investigated by impedance spectroscopy. In the case of Ag2HgI4 and Cu2HgI4 we found clear changes of conductivity not present with HgI2. In all cases the main resistance is caused by the grain boundaries between the single crystals of the powder sample. Also diffusion in the double layer in front of the surface of the electrodes influences the spectra. Single crystal measurements of Hgl, show the different ionic mobilities along the various crystallographic directions.

Two methods are reported for the indirect determination of thiosulphate down to ca. 0.02 μg/ml by differential-pulse polarography. Both methods involve prior oxidation of thiosulphate with iodine, either in acidic medium to tetrathionate or in alkaline medium to sulphate, whereby ultimately one and eight equivalents of iodate are obtained, respectively. The concentration of iodate in the resulting solution is then measured by differential-pulse polarography under optimum conditions. The average recovery for each method amounted to 100.1%, and the relative standard deviations were 1.3 and 1.4% for the two methods.

Information concerning the chemical substances that make up electronic devices is hardly available, so current processing of obsolete electronics is not effective. Providing chemical information by modern analytical chemistry means that electronics scrap is characterized. Based on this knowledge a laboratory scale combination process has been established, which takes care of both, metals and plastics, forming the parts of electronic devices. Considering these chemical aspects, a more ecological design of future electronics is possible. >

Antimyosin Fab fragment has been shown to bind to myosin leaked from necrotic cardiac cells but not to myosin in undamaged cells. The purpose of this investigation was to evaluate indium 111-antimyosin Fab fragment scintigraphy as a noninvasive technique in the diagnosis of acute rejection after heart transplantation. Simultaneous endomyocardial biopsy served as the gold standard.Twenty-two patients had scintigraphic studies at weeks 3 to 4, 6, 10, 26, and 52, but the next 16 patients underwent scintigraphy more often, that is, at all scheduled biopsies performed from week 3 to week 26 after transplantation. From analysis of the first 70 studies, an interstudy decrease in the patient's heart-to-lung ratio was classified as normal, that is, no rejection, whereas an unchanged or increased heart-to-lung ratio was considered pathologic.By use of this definition of negative and positive scintigraphic results, prospective analysis of 88 conclusive, consecutive studies showed 6 true- and 31 false-positive studies (prevalence of rejection 8%), giving a low predictive value of a pathologic change in heart-to-lung ratio. Of the 51 studies with decreasing heart-to-lung ratio only 1 was a false negative, giving a predictive value of a negative study of 98% (95% confidence limits 90% to 100%).In conclusion, antimyosin scintigraphy is a promising noninvasive technique in the routine surveillance of acute heart rejection. Because of many false-positive results in the studies, biopsy should be used as a control for a pathologic heart-to-lung ratio.

The aggregation properties of zinc-free insulin have been studied using static and dynamic light scattering. The aggregation has been investigated as a function of three parameters, the concentration of sodium chloride (in the range 10-100 mM), the pH value (in the range pH 7.5-10.5), and the insulin concentration (1.8-13.4 mg/mL). The measured homodyne autocorrelation function was used to determine the apparent mean hydrodynamic diameter as well as the apparent weight-averaged molar mass of the insulin species in solution. A method of data analysis was employed, which allows the separation of light scattering contributions from the insulin oligomers and from irrelevant macromolecules and possible impurities present in the sample solutions. Also, a simple phenomenological equilibrium model describing the association of oligomers of insulin is presented. One aspect of this model is that it makes it possible to determine weight average molar masses corrected for virial effects on the Rayleigh ratio. This was necessary because virial effects cannot be isolated and corrected for by dilution since this would change the equilibrium distribution of oligomers. The basis of the model is a positive contribution to Gibbs free energy from charge repulsion depending on the protein charge and the number of monomers in the oligomers, and an assumed constant negative contribution to Gibbs free energy arising from either an entropic gain or hydrogen bonding upon association. The equilibrium model gives a good description of both the apparent weight average molar masses and the apparent hydrodynamic diameters, when the effect of the insulin concentration is taken into account by including virial effects arising from charge-charge repulsion (Donnan effect). The result shows that the association of insulin as a function of pH and ionic strength can be described by an effective charge equal to the charge derived from proton titration reduced by the number of sodium ions binding to insulin. At the lowest pH and highest salt concentration (pH 7.5, 100 mM NaCl, 12 mg/mL insulin), the weight average molar mass is close to that of the hexamer, and at the highest pH and lowest salt concentration (pH 10.5, 10 mM NaCl, 1.9 mg/mL), the weight average molar mass is close to that of the monomer. In all cases, however, a distribution of oligomers is present with a relative Gaussian width of about 30%.(ABSTRACT TRUNCATED AT 400 WORDS)

Two methods are reported for the indirect determination of thiosulphate down to ca. 0.02 microg/ml by differential-pulse polarography. Both methods involve prior oxidation of thiosulphate with iodine, either in acidic medium to tetrathionate or in alkaline medium to sulphate, whereby ultimately one and eight equivalents of iodate are obtained, respectively. The concentration of iodate in the resulting solution is then measured by differential-pulse polarography under optimum conditions. The average recovery for each method amounted to 100.1%, and the relative standard deviations were 1.3 and 1.4% for the two methods.

Die Hydrate der Dihalogenomonocyanomercurate KHgX2CN · H2O (X = Cl, Br) bilden sich bei der Umsetzung aquimolarer Mengen von HgX2 und KCN in wasriger Losung. In der Kristallstruktur des rhombischen KHgBr2CN · H2O (a = 454,2 pm; b = 1738,1 pm; c = 465,1 pm; Pmmm; Z = 2) liegen nebeneinander digonale HgBr2- und Hg(CN)2-Gruppen, sowie isolierte Br−- und K+-Ionen vor, so das die Verbindung als Doppelsalz Hg(CN)2 · HgBr2 · 2 KBr · 2 H2O zu formulieren ist. Die Chlorverbindung ist isotyp.

Das durch Umsetzung von Chinolin mit Quecksilber(I)-nitrat aus wasrigen Losungen erhaltene [C18H14Hg2N2](NO3)2 kristallisiert monoklin (a = 1 062,8(9) pm, b = 1 021,9(8) pm, c = 1 823,6(15) pm, β = 100,35 ± 0,06°) in der Raumgruppe C2/cC (Nr. 15) mit Z = 4. Die Struktur wurde rontgenographisch mittels Patterson- und Fourier-Synthesen gelost und nach der Methode der kleinsten Fehlerquadrate bis zu einem R-Wert von 0,091 verfeinert. Die Substanz ist aufgebaut aus isolierten [ ]-Gruppen, zwischen denen die Nitrationen liegen. Stable Mercury(I)-Nitrogen Compounds. VI. Synthesis and Crystal Structure of Bis(chinoline)Dimercury(I) Dinitrate The product of the reaction of aqueous solutions of mercury(I) nitrate and chinoline, Bis(chinoline)dimercury(I) dinitrate, [C18H14Hg2N2](NO3)2, crystallizes monoclinic (a = 1 062.8(9) pm; b = 1 021.9(8) pm; c = 1 823.6(15) pm; β = 100.35 ± 0.06°) in the space group C2/cC (Nr. 15) with Z = 4. The X-ray structure has been determined using Patterson and Fourier syntheses and refined by least squares to an R value of 0.091. The results show that the compound exists as a group structure of units with the nitrate anions occupying positions between the groups.

p-Aminobenzoesaure, Nicotinsaure, Sulfanilsaure und Pyridin(3)-sulfo-saure wurden mit Quecksilber(I)-nitrat und -perchlorat umgesetzt. Die beiden Carbonsauren reagierten zu Verbindungen der Zusammensetzung (Hg2L)NO3 (L = H2NC6H4COO−, C5H4NCOO−) bzw. (Hg2L)ClO4 (L = C5H4NCOO−). Die IR-Spektren lassen auf Kettenstrukturen mit den Bauelementen [HgH2C6H4-COOHg]NO3− und [HgC5H4COOHg]X− (X− = NO3−, C1O4−) schliesen. Die Reaktionsprodukte der Umsetzungen mit den beiden Sulfosauren waren Hg2(H2NC6H4SO3)2 und Hg2(NC5H4SO3)2 · 2H2O. Diesen Stochiometrien entsprechen Gruppenstrukturen LHgHgL. Die Rontgenstrukturanalyse von Bis[pyridin(3)-sulfonat]diquecksilber(I)-dihydrat hat ge-zeigt, das die Hg2-Gruppe an den Pyridinstoff gebunden wird. Das Sulfonat-Anion kompensiert die positive Formalladung des Stickstoffs. Es liegt ein Zwitterion vor. Das IR-Spektrum last auch fur Bis(sulfanilat)-diquecksilber(I) auf eine zwitterionische Struktur schliesen. Stable Mercury(I)-Nitrogen Compounds. 9. Compounds of Four Aromatic Carboxylic Respectively Sulfonic Acids with Mercury(I) Salts and Crystal Structure of Bis [pyridine (3) -sulfonate] dimercury(I) Dihydrate Reactions of p-aminobenzoic acid, nicotinic acid, sulfanilic acid, and pyridine(3)-sulfonic acid with mercury(I) nitrate and perchlorate have been carried out. The two carboxylic acids give products of the compositions (Hg2L)NO3 (L = H2NC6H4COO−, C5H4NCOO−) and (Hg2L)C1O4 (L = C5H4NCOO−). The i.r. spectra indicate that the compounds exist of chains containing units [HgH2C6H4COOHg]NO3− and [HgC5H4COOHg]X− (X− = NO2−, C1O4−). From the reactions with the two sulfonio acids, the compounds Hg2(H2NC6H4SO3)2 and Hg2(NC5H4SO3)2 · 2H2O have been obtained. These stoichiometries refer to group structures LHgHgL. An X-ray crystal structure determination has shown that the Hg2 group is linked to the pyridine nitrogen. The sulfonate anion compensates the formal positive charge on the nitrogen; a Zwitterionic structure results.

Hg4O2(NO3)2 kristallisiert monoklin in der Raumgruppe P21/a – Standard aufstellung P21/c (C) – mit a = 1158,0(2), b = 666,4(1), c = 553,3(1) pm, β = 98,82(1)° und Z = 2. Die Strukturbestimmung aus Einkristalldiffraktometerdaten (AgKα, 1170 I0(hkl), numerische Absorptionskorrektur) lieferte R = 5,12% (RW = 6,85%). In der gemisch-valenten Verbindung liegen gewellte Schichten [(HgII)2/2O(Hg)1/2]+ vor, die parallel (201) verlaufen. Wahrend in den Schichten ausschlieslich kovalente HgHg- bzw. HgO-Bindungen auftreten, erfolgt die Verknupfung zwischen den Schichten durch schwache HgIO-Kontakte und uber Nitratanionen, die als schwache Bruckenliganden zwischen Hg-Atomen fungieren. Die gefundene Schichtstruktur erklart die ausgepragte Spaltbarkeit der Kristalle von Hg4O2(NO3)2. Crystal Structure of the Basic Dimercury(I) Nitrates. III. Crystal Structure of Hg4O2(NO3)2 Hg4O2(NO3)2 crystallizes monoclinic, space group P21/a – standard setting P21/c (C) – with a = 1158.0(2), b = 666.4(1), c = 553.3(1) pm, β = 98.82(1)° and Z = 2. The structure determination from single crystal diffractometer data (AgKα, 1170 I0(hkl), numerical absorption corrections applied) resulted in a final R = 0.0512 (Rw = 0.0685). The mixed valence compound is built up of puckered layers [(HgII)2/2O(Hg)1/2]+ parallel (201). Within the layers there are exclusively covalent HgHg and HgO bonds; whereas the linkage between the layers is achieved by weak HgIO contacts and by nitrate ions functioning as weak bridging ligands for mercury atoms. This layer structure explains the distinct cleavage of crystals of Hg4O2(NO3)2.

Durch Reaktion zwischen Hg(CN)2 und den Erdalkalithiocyanaten M(NCS)2 · nH2O (M = Mg, Ca, Sr, Ba; n = 3, 4) in H2O wurden die Verbindungen M[Hg(CN)2SCN]2 · 4H2O dargestellt. Die kristallinen Spezies wurden durch rontgenographische, spektrometrische und thermische Methoden charakterisiert. Die Strukturen der Verbindungen mit M = Mg und Sr konnten bestimmt werden. Der strukturelle Aufbau last Vergleiche mit den entsprechenden Verbindungen der Alkaliionen M′Hg(CN)2SCN (M′ = K, Rb, Cs) zu. On the Dicyanothiocyanatomercurates(II) of the Alkaline-earth Metals The reactions between Hg(CN)2 and M(NCS)2 · nH2O (M = Mg, Ca, Sr, Ba; n = 3, 4) in aqueous solutions lead to the compounds M[Hg(CN)2SCN]2 · 4 H2O. The compounds yielded by crystallization are characterized with x-ray, spectroscopic, and thermal methods. The crystal structures of Mg[Hg(CN)2SCN]2 · 4 H2O and Sr[Hg(CN)2SCN]2 · 4 H2O have been determined by x-ray structure analysis. These structures can be compared with the compounds M′Hg(CN)2SCN (M′ = K, Rb, Cs).

Das durch Umsetzung von 1,3-Dithian mit Quecksilber(I)-nitrat aus methanolischen Losungen erhaltene Addukt, (C4H8S2Hg2)(NO3)2, kristallisiert monoklin (a = 697,0 ± 0,5 pm, b = 1 520,5 ± 0,8 pm, c = 1 118,5 ± 0,8 pm, β = 96 ± 0,6°) in der Raumgruppe P21/c—C (Nr. 14) mit Z = 4. Die Kristallstruktur wurde rontgenographisch mit Fourier-Methoden bestimmt und durch Least-squares-Verfahren bis zu einem R-Wert von 0,068 verfeinert. Die Substanz ist aus gewinkelten Ketten aufgebaut, zwischen denen die Nitrat-Ionen verknupfend wirken. Stable Mercury (I)-Sulfur Compounds. II. Crystal Structure of 1,3-Dithiane-dimercury(I) Dinitrate The product of the reaction of methanolic solutions of 1,3-Dithiane and Dimercury(I) dinitrate, the addukt (C4H8S2Hg2)(NO3)2, crystallizes monoclinic (a = 697.0 ± 0.5 pm, b = 1 520.5 ± 0.8 pm, c = 1 118.5 ± 0.8 pm, β = 96 ± 0.6deg;) in the space group P 21/c—C (Nr. 14) with Z = 4. The X-ray structure has been determined using Fourier methods and refined by least-squares to an R-value of 0.068. The results show that the compound exists as a chain structure of with nitrate ions connecting the chains.

In der Kristallstruktur des monoklinen MgHg(SCN)4 · 2 H2O (a 1 335,1(6) pm, b 531,6(5) pm, c 1 867,0(14) pm, β 92,3(1)°, Z 4, Raumgruppe C2/c) sind annahernd tetraedrische Hg(SCN)4- und oktaedrische Mg(OH2)2(NCS)4-Baugruppen uber HgSCNMg-Brucken zu Schichten verbunden. Crystal Structure of MgHg(SCN)4 · 2 H2O The crystal structure of the monoclinic MgHg(SCN)4 · 2 H2O (a 1 335.1(6) pm, b 531.6(5) pm, c 1 867.0(14) pm, β 92.3(1)°, Z 4, space group C2/c) contains nearly tetrahedral Hg(SCN)4 and octahedral Mg(OH2)2(NCS)4 groups. These groups are joined together with HgSCNMg bridges and are forming a network of layers.

Die Kristallstruktur des Terlinguaits wurde an einem synthetischen Einkristall mit absorptionskorrigierten Diffraktometerdaten neu bestimmt. Raumgruppe C 2/c (Nr. 15 der IT), mit a = 1 195,3(4), b = 590,4(3), c = 946,6(4) pm, β = 105,59(6)o und Z = 4. Die Struktur stellt ein einziges, hoch vernetztes Riesenmolekul dar, in dem ganz ungewohnliche Hg3-Cluster als Baueinheiten mit Hg–Hg-Bindungslangen von 270 pm vorliegen. Die nahezu planare Viererumgebung um alle Hg-Atome des Dreirings ist als weitere Variante der Bauprinzipien von Quecksilberverbindungen anzusehen. Terlinguaite Hg4O2Cl2, a Mineral with Unusual Hg3 Units The crystal structure of Terlinguaite was redetermined from a synthetic single crystal with absorption corrected diffractometer data. Space group C 2/c with a = 1 195.3(4), b = 590.4(3), c = 946.6(4) pm, β = 105.59(6)o and Z = 4. The structure shows a single high density network of a giant molecule, in which unusual Hg3-clusters as building units appear with Hg–Hg bond lengths of 270 pm. The nearly planar fourfold coordination of all Hg-atoms in the 3-membered ring is to be seen as a further variation of mercury compounds' building units.

Geschmolzenes Quecksilber(II)-bromid (Arbeitstemperatur 242°C) erweist sich als stabilisierendes Medium fur Quecksilber(I)-Verbindungen. Die kovalenten Quecksilber(I)-Halogenide Hg2X2 verhalten sich wie schwache Solvobasen, die mit Solvosauren HgBrA (A z.B. CIO4) unter Bildung bisher unbekannter Quecksilber(I)-Halogenosalzen Hg2XA reagieren. Quecksilber(I)-Salze von Mineralsauren Hg2A2 unterliegen in Schmelze der Solvolyse. Die Lage des Gleichgewichts und die Art der Solvolyseprodukte wird entscheidend vom Anion A beeinflust. Im Gegensatz zu den Blei(II)-Halogeniden PbX2 reagieren die Zinn(II)-Halogenide SnX2 nicht zweibasig als Sn(HgBr3)2, sondern einbasig als Lewis-Basen. Zinn(II)-bromid bildet mit Hg2Br2 ein losliches 2:1 Addukt, welches mit NEt4ClO4 (Et C2H5) als Perchlorat ausgefallt werden kann. Zur selben Reaktion kommt es bei Angriff der Lewis-Base SnBr2 auf die Lewis-Saure Hg2BrClO4, welche nach 4 verschiedenen Methoden erzeugt wurde. Investigations with Mercury (I) Compounds and Tin (II) Halides in Molten Mercury (II) Bromide Molten mercuric bromide HgBr2 (experimental temperature 242°C) is a very stabilizing medium for mercurous compounds. The covalent mercurous halides Hg2X2 are weak solvobases in molten HgBr2, i. e. in solution exist only a few dissociated associates [Hg2X(Hg2X2)n]+ (HgBr2X)−, which react with a solvoacid HgBrA (A i. e. ClO4) to a hitherto unknown type of compound Hg2XA. Mercurous salts of mineral acids Hg2A2 are solvolized in the melt (HgBrA, Hg2BrA, Hg2Br2…). The state of equilibrium and the type of the products are mainly influenced by the anion A. In contrary to the lead(II) halides PbX2 the tin(II) halides SnX2 react not as Sn(HgBr3)2 (two-basic) but onebasic as a Lewis base. Conductometric investigations show that SnBr2 formes a soluble 2:1 adduct with Hg2Br2, which can be precipitated as perchlorate with NEt4ClO4 (Et C2H5). The same reaction takes place, if the Lewis base SnBr2 attacks the Lewis acid Hg2BrClO4, which was generated by 4 different methods.

Die Kristallstrukturen der Verbindungen Hg2(p-H2N–C6H4–SO3)2 (1), Hg2(m-H2N–C6H4–SO3)2 (2) und Hg2(m-H2N–C6H4–SO3) 2 · 2H2O (3) enthalten Blattstrukturen (1 und 3) oder Kettenstrukturen (2), die durch Verknupfung der nahezu linearen Baueinheiten N–Hg–Hg–N durch koordinative Hg–O-Kontakte und Bildung von Wasserstoffbruckenbindungen entstehen. Die geringere Dichte von 3 verglichen mit 1 – bedingt durch grosere sterische Hinderung des Liganden – last den Einbau von Kristallwasser zur Erhoung der stabilisierenden Wechselwirkungen innerhalb des Kristalles plausibel erscheinen. Die Verbindung 3 ist das kinetisch kontrollierte, die Verbindung 2 das thermodynamisch kontrollierte Produkt. Crystal Structures of Dimercuri (I) Salts of p- and m-Sulfanilic Acids The crystal structures of the compounds Hg2(p-H2N–C6H4–SO3)2 (1), Hg2(m-H2N–C6H4–SO3)2 (2), and Hg2(m-H2N–C6H4–SO3)2 · 2H2O (3) contain leaf-structures (1 and 3) or chain-structures (2), with nearly linear groups N–Hg–Hg–N, Hg–O-contacts and hydrogen-bridging bonds. The smaller density of 3 compared with 1–caused by the steric hindrance through the ligand – declared the incorporation of water for raising the stabilising interaction in the crystals. The compound 3 is the kinetic controlled, the compound 2 the thermodynamic controlled product.

Die Elementarzelle von Hg2OH(NO3) · Hg2(NO3)2 ist orthorhombisch, Raumgruppe Cc2a — Standardaufstellung Aba2 (C) — mit a = 2017,1(5) pm. b = 935,8(3) pm, c = 1121,7(3) pm und enthalt 8 Formeleinheiten. Charakteristisch sind Ketten [Hg2OH(Hg2)2/2 ]3+ parallel [001]. an Quecksilber koordinierte Nitrationen verknupfen diese zu einem dreidimensionalen Netzwerk. Zusatzliche Stabilisierung erfahrt die Struktur durch schwache Wasserstoffbruckenbindungen zwischen dem Sauerstoffatom der Hydroxylgruppen und benachbarten Nitrationen. Die Bindungsbeziehung eines Wasserstoffatoms zu vier tetraedrisch angeordneten Sauerstoffatomen wird diskutiert. The Crystal Structure of the Basic Dimercury (I) Nitrates. I. The Crystal Structure of Hg2OH(NO3) · Hg2(NO3)2 The unit cell of Hg2OH(NO3) · Hg2(NO3)2 is orthorhombic, space group Cc2a - standard setting Aba2 (C) — with a = 2017.1(5) pm, b = 935.8(3) pm, c = 1121.7(3) pm and contains 8 formula units. Characteristic are chains [Hg2OH(Hg2)2/2]3+ parallel [001]. These are interconnected to a three-dimensional network by nitrate ions coordinated to mercury. The structure achieves additional stabilization through weak hydrogen bonds between oxygen atoms of the hydroxy groups and neighbouring nitrate ions. The bonding relationship of one hydrogen atom to four tetrahedrally correlated oxygen atoms is discussed.

SrHg(SCN)4 · 3H2O ist orthorhombisch, Raumgruppe Pcca, mit a = 19,476(7), b = 8,150(1), c = 8,991(3) A, V = 1427,1 A3, Z = 4, dc = 2,67 g · cm−3, μ(AgKα) = 77,95 cm−1. In der Verbindung sind annahernd tetraedrische Hg(SCN)4-Einheiten enthalten. Sr besitzt eine tricapped trigonal prismatische Koordination (4 N- und 5 O-Atome). Die Thiocyanatogruppen liegen als end-to-end-Brucken vor und verbinden die beiden Koordinationspolyeder. Crystal Structure of SrHg(SCN)4 · 3 H2O SrHg(SCN)4 · 3 H2O is orthorhombic, space group Pcca, with a = 19.476(7), b = 8.150(1), c = 8.991(3) A, V = 1427.1 A3, Z = 4, dc = 2.67 g · cm−3, μ(AgKα) = 77.95 cm−1. The salt consists of nearly tetrahedral Hg(SCN)4 groups, Sr has a tricapped trigonal prismatic coordination: four N and five O atoms. The thiocyanate groups form end-to-end bridges and connect the Hg and Sr coordination polyhedra.

Platin(II)-chlorid wurde mit Hilfe von Transportreaktionen in Form von schwarzroten Einkristallen dargestellt. Rontgenographische Untersuchungen unter Verwendung von FOURIER-Methoden fuhrten zu folgendem Strukturmodell: Das Platin(II)-chlorid besitzt eine Inselstruktur mit diskreten [Pt6Cl12]-Gruppen. Die sechs Platinatome bilden ein Oktaeder, uber dessen Kanten die zwolf Chlor-Teilchen liegen. Dabei ist jedes Platin-Atom annahernd planar quadratisch von vier Chlor-Atomen umgeben, wahrend jedes Cl-Teilchen seinerseits zu je zwei Pt-Teilchen gehort. Die Verbindung ist diamagnetisch. Das Reflexionsspektrum weicht etwas von dem anderer Platin(II)-Chlor-Verbindungen ab. Auf Grund der speziellen Baugruppen [Pt6Cl12] kann man auf Metall–Metall-Wechselwirkungen schliesen. By use of chemical transport reactions black-red single crystals of platinum(II) chloride were prepared. X-ray work with FOURIER methods shows that platinum(II) chloride has an insular structure with discret [Pt6Cl12] groups. The 12 chlorine atoms are situated above the edges of an octahedron built up by six platinum atoms. The PtCl coordination is fourfold planar with respect to platinum and twofold angular with respect to chlorine. Platinum(II) chloride is diamagnetic. Its reflexion spectrum is somewhat different of those of other platinum(II) compounds with chlorine ligans. The assumption of metal-metal interactions agrees well with the existence of discret [Pt6Cl12] units.