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The supercooling and vitrification of aqueous glycerol solutions was studied at high pressures. Homogeneous ice nucleation temperatures (TH) were obtained for aqueous glycerol solutions of R = 50, 30, 20, 12, and 10 (R: moles of water/moles of glycerol) up to 300 MPa. The R = 20 glycerol solution formed a glass above 200 MPa at a cooling rate of 200 °C/min, indicating that pressure enhances glass-formation of aqueous glycerol solutions. The (dTg/dP) values were obtained for vitrified aqueous glycerol solutions of R = 3, 5, 10, and 20. These data can be used for the development of cryo-preservation liquids for living cells at high pressures.

Yokukansan (YKS), a traditional Japanese medicine, is composed of seven kinds of dried herbs. It is widely prescribed in clinical situation for treating psychiatric disorders such as aggressiveness in patients with dementia. We previously demonstrated that YKS and Uncaria hook (UH), which is a constituent herb of YKS, had a partial agonistic effect to 5-HT(1A) receptors in vitro. However, it has still been unclear whether this in vitro effect is reflected in in vivo, and what the active ingredients are. The purpose of the present study is to find the active ingredient in YKS and to demonstrate the effect in in vivo. In the present study, we first studied the effect of YKS and UH on aggressiveness and sociality in socially isolated mice. YKS and UH ameliorated the isolation-induced increased aggressiveness and decreased sociality, and these ameliorative effects were counteracted by coadministration of 5-HT(1A) receptor antagonist WAY-100635, or disappeared by eliminating UH from YKS. These results suggest that the effect of YKS is mainly attributed to UH, and the active ingredient is contained in UH. To find the candidate ingredients, we examined competitive binding assay and [(35)S] guanosine 5'-O-(3-thiotriphosphate) (GTPγS) binding assay of seven major alkaloids in UH using Chinese hamster ovary cells expressing 5-HT(1A) receptors artificially. Only geissoschizine methyl ether (GM) among seven alkaloids potently bound to 5-HT(1A) receptors and acted as a partial agonist. This in vitro result on GM was further demonstrated in the socially isolated mice. As did YKS and UH, GM ameliorated the isolation-induced increased aggressiveness and decreased sociality, and the effect was counteracted by coadministration of WAY-100635. These lines of results suggest that GM in UH is potent 5-HT(1A) receptor agonist and a candidate for pharmacological effect of YKS on aggressiveness and sociality in socially isolated mice.

Homogeneous ice nucleation temperatures ( T H s) of aqueous sucrose, trehalose, and maltose solutions were measured together with melting temperatures ( T m s). It is shown that there is a linear relation between T H and T m for these solutions. Almost identical supercooling behavior is observed for these aqueous disaccharide solutions.

Complex formation of rare earth ions with thiocyanate ions was investigated in the presence of coexisting anions (Cl− or ClO4− ions). From the frequency variations of the CS and CN stretching Raman bands, it is shown that both the coordination number change in the middle of the series and the complex formation of rare earth ions with thiocyanate ions are affected by the coexisting anions. Some discussion was made on the anomalous behavior of the coordination number change with the salt concentration.

Homogeneous ice nucleation temperatures (THs) were measured as a function of solute concentration for aqueous solutions of alcohols (methanol, ethylene glycol, glycerol and xylitol) and sugars (glucose, fructose, sucrose, maltose and trehalose). It is found that there is a linear relation between TH and the number of OH groups in an alcohol molecule. It is also found that small configurational difference of the solute molecule gives rise to little TH difference.

Raman spectroscopic measurements were carried out for the anhydrous LnCl3·20MeOH·XLiCl solutions (Ln3+=Pr3+, Gd3+ and Ho3+, X=0–4) in both liquid and glassy states. Salt concentration dependence of the frequency for the Ln–Cl stretching Raman band (νLn–Cl) is examined in conjunction with the formation of chloro-rare earth complexes. We have obtained the very interesting results that the chloro-complexations of gadolinium and holmium ions in these solutions show very peculiar behavior as to the salt concentration dependence at room temperature: the νLn–Cl frequency increases with increasing concentration. On the other hand, the νLn–Cl frequency of the PrCl3·20MeOH·XLiCl solution shows normal behavior as to the salt concentration dependence: νLn–Cl decreases with increasing chloride concentration. We present a possible mechanism for this anomalous concentration dependence of coordination of Cl− ions to Ln3+ ions in anhydrous methanol LnCl3 solutions.

Aim: The objective of this study was to investigate whether the presence of small, dense lipoproteins, which are thought to be related to the metabolic syndrome caused by insulin resistance, can be predicted by routine serum lipid profiling. Methods: The relationship between low-density lipoprotein (LDL) particle size and serum lipid levels was analysed in 284 school children (148 boys and 136 girls), aged 7 to 13 y old. LDL particle size was determined by gradient gel electrophoresis. Results: The LDL particle diameter was significantly correlated with the serum levels of high-density lipoprotein cholesterol (HDL-C) (r= 0.437, p > 0.001) and triglycerides (TG) (r= 0.432, p 0.001), and with the atherogenic index (AI) [total cholesterol/HDL-C] (r= 0.450, p > 0.001), while only weak correlations were observed with the serum levels of total cholesterol, apolipoprotein A1 and apolipoprotein B. No significant relationship was observed between LDL particle diameter and the serum LDL-C level. Conclusion : The presence of small, dense LDL as a metabolic marker of lifestyle-related diseases in children seems to be reflected by a serum lipid profile characterized by an elevation in TG, a reduction in HDL-C, and a raised AI.

Hydrogen bonding in aqueous N,N-dimethylformamide (DMF) and N,N-dimethylacetamide (DMA) solutions was studied by Raman spectroscopy of the OH-stretching spectra of water as functions of solute concentration and temperature (from –50 to 50 °C). The Raman spectra were decomposed successfully into two components (the low- and high-frequency components). The peak area ratio of the low-frequency component to the high-frequency component increases exponentially with decreasing temperature. The frequency of the low-frequency component decreases linearly with lowering temperature down to –50 °C at all solute concentrations (solute mol fraction from 0.3 to 0.7). It is shown that the hydrogen bonds in the clathrate structures around DMA molecules are stronger than those around DMF molecules.Key words: Raman spectrum, DMF, DMA, aqueous solution, low temperature.

The thermal decomposition of the lanthanoid trifluoromethanesulfonate (triflate) complexes {Ln(CF3SO3)3·9H2O; Ln=La-Lu{ was studied by TG and DTA methods. From the endothermic and exothermic data of Ln(CF3 SO3)3·9H2O complexes, pyrolysis behavior of the complexes is classified into three groups: 1) La-Nd salts, 2) Sm-Ho salts, 3) Er-Lu salts. It has also shown that all the final decomposition products were found to result in the formation of LnF3.

SUMMARYIn this study we established a new animal model for exploring the pathogenesis of autoimmune pancreatitis. We have found previously that MRL/Mp-+/+(MRL/+) mice develop pancreatitis spontaneously by an autoimmune mechanism but only when they are more than 34 weeks old. Because this disease might be a model of multi-factorial diseases controlled by genetic and environmental factors, beginning at 6 weeks old, we injected polyinosinic:polycytidylic acid (poly I:C) into MRL/+ mice and in addtion, into MRL/Mp mice bearing the Fas deletion mutant gene, lpr (MRL/lpr). Poly I:C induced chronic severe pancreatitis in all the MRL/+ mice and to a lesser extent in the MRL/lpr mice by 18 weeks of age. There was no pancreatitis in control mice of both strains at the same age. Other than chronic pancreatitis, no severe autoimmune diseases were observed in MRL/+ mice. Immunohistochemical examinations revealed predominant infiltration of CD4+ T cells and Mac-2+ activated macrophages in the pancreatic lesions. Splenic expression of the mRNAs for TNF-α and IL-10, which is known to suppress the development of pancreatitis, were increased in both strains of mice. These findings suggest that an MRL strain of mice treated with poly I:C might be a good model for developing new approaches to the study of the pathogenesis of autoimmune pancreatitis.

Supercooling behavior of aqueous tetraalkylammonium chloride solution {R4NCl, R = methyl (Me), ethyl (Et), and n-propyl (Pr)} was investigated using emulsification method at high pressures. The magnitude of the supercooling at normal pressure is in the order: Pr4NCl > Et4NCl > Me4NCl while it becomes in the reversed order at high pressures (∼ 200 MPa): Me4NCl > Et4NCl > Pr4NCl. It is shown that the supercooling behavior of these solutions is closely related to intrinsic clathrate-like structures in pure water. In addition, it is suggested that bulky cage-like structures can not be formed at higher pressures than ∼ 200 MPa in water and aqueous solutions.

Test of the linear relation between TH (homogeneous ice nucleation temperature) and Tm (melting temperature) was carried out for aqueous HCl and H2SO4 solutions. It is shown that the linear relation does not hold for aqueous H2SO4 solution. Enhancement of the ionization of sulfuric acid with decreasing temperature is the most likely cause for the curved relation between TH and Tm. In addition, close examination of the TH and Tm data for aqueous HCl solution indicates that the TH versus Tm relation for aqueous HCl solution seems very weakly curved.

An attempt has been made to interpret the anomalous properties of supercooled water in a unified way by using Stillinger's postulate that the formation of bulky clathrate-like local structures is the main cause of the anomalous thermodynamic and transport properties exhibited by liquid water at low temperatures. Comparison of the thermodynamic properties of liquid water, tellurium, and sulfur suggests the existence of a λ-like Cp transition in supercooled water below TH (but above TK). It is inferred that the diverging trends of various anomalous properties with lowering temperature are preserved up to high pressures (

Raman spectroscopic measurements were carried out for anhydrous alcoholic rare earth chloride solutions (LnCl3 · 20ROH; ROH = MeOH, EtOH, and n-PrOH) in the glassy state at liquid nitrogen temperature. Series behavior of the Ln–Cl stretching Raman band is examined in conjunction with the formation of chloro complexes. The results are summarized as follows: (1) Comparing the results with those in the liquid state at room temperature, more Cl- ions tend to coordinate to heavy rare earth ions in the three alcohol solutions upon going from a liquid to a glassy state, while the coordination number of the Cl- ions of the light rare earth ions remains almost unchanged on vitrification. (2) In the former half region of the rare earth series, the coordination number of the Cl- ions of the rare earth ions in the methanol LnCl3 solution is apparently the same as that in the ethanol LnCl3 solution. (3) In the latter half region, the higher chloro complexes, such as [LnClx+1(ROH)y-2](z-1) (x + y = 8; x = 1, z = 2 or x = 2, z = 1) are more abundant in the methanol LnCl3 solution than in the ethanol and n-propanol LnCl3 solutions.

Raman spectra were obtained for alcohol solutions with inert solvents such asCCl4, CHCl3, etc. The frequency of the OH stretching vibrations[νOH(free) band]due to free hydrogen bonds varies with change in either alcohol or inert solvent.It is shown that the frequency of the νOH(free) band is sensitive to the shape ofthe head group of an inert solvent. The main cause for the frequency change ofthe νOH(free) band with change in alcohol is ascribed to the change of effectivemass of the vibrating unit (RO-H, R = alkyl group).

The supercooling and glass-forming behavior of aqueous sucrose solution was investigated using emulsified sucrose solutions at high pressures. It is shown that emulsified aqueous sucrose solution with the sucrose concentration being as low as 1 m (m: molality) is glass-forming at high pressures above 190 MPa. This finding may form the basis of a useful vitrification method for cryo-preservation of living cells and tissues at high pressures.

Raman spectra of the OH-stretching, HOH-bending and low-frequency (115∼800 cm −1 ) regions were measured for both low- and high-density amorphous ices (LDA and HDA, respectively). There are close similarities in spectral features between LDA and crystal ice I. The Raman spectrum of HDA is more similar to that of glassy aqueous LiCl solution than to that of LDA.

Raman Ln–Cl stretching spectra (Ln=rare earth ion) were measured for alcoholic solutions (alcohol=methanol, ethanol and n-propanol) of anhydrous rare earth chlorides. From the extended s-shaped variation of the frequency for the Ln–Cl stretching Raman band across the series, it is concluded that the inner-coordination number of rare earth ions decreases by one in the latter region of the rare earth series.

Raman measurements were carried out for aqueous rare earth thiocyanate [Ln(SCN) 3 ; Ln=La 3+ ~Lu 3+ ] solutions ( R =20; R is moles of water per moles of salt) in the liquid state at room temperature and in the glassy state at liquid-nitrogen temperature. Raman band shifts for the C-S and C-N stretching bands of the SCN − ion indicated that the SCN − ion binds to a rare earth ion only at the N end. Thus, these solutions are better called as aqueous rare earth isothiocyanate solutions. Glass transition temperatures ( T g 's) of these solutions were also measured. The T g values have a distinct extended s-shape and are compared with the previous ones for aqueous rare earth chloride and perchlorate solutions. Series behavior of the T g results is discussed in conjunction with the coordination number change in the middle of the series.

Glass transition temperatures T g and Raman spectra of KPO 3 ·Ln(PO 3 ) 3 (Ln=rare earth ion) glasses were measured for all rare earth members (except Pm). From the series behavior of the T g and Raman data, it is concluded that the coordination number around rare earth ions changes, probably from nine to eight, in the middle of the rare earth series.

The glass-forming composition regions of aqueous tetraalkylammonium nitrate solutions (alkyl = ethyl and n-propyl) were determined by a simple DTA method with a cooling rate of about 600 K-min−1. The glass transition temperatures Tg of these solutions vary in a different manner from those for simple inorganic salt solutions such as aqueous LiCl, MgCl2,and AlCl3 solutions. Liquid-liquid immiscibilities are observed in these solutions at low temperatures.

Raman spectra were measured for aqueous solutions of Sc − , Ln − and M − nitrates (Lnlanthanoids; MAl, Ga and In). A comparison was made between the coordination of NO 3 − ions to the metal ions in these solutions. It is concluded that Sc 3+ behaves differently to lanthanoid ions in its complex formation with NO 3 − ions. A hydration number of seven is inferred for aqua-Sc 3+ ions from the Raman data of these nitrate solutions.

The glass transition temperature T g of an aqueous CsF solution was measured as a function of CsF concentration, and Raman spectra of the solution were obtained for both liquid and glassy states. The results were discussed in comparison with those for aqueous LiX (X=Cl, Br and I) and HF solutions.

Raman spectra of alcoholic lithium Perchlorate solutions (alcohol = methanol and ethanol) were measured as a function of LiClO4 concentration. The Raman band due to nearly free hydrogen bonds shows peculiar concentration dependences: (1) its frequency shifts with LiClO4 concentration in contrast to alcoholic LiX solutions (X = CI and Br), in which the Raman band due to solvated halide ions shows little frequency change with LiX concentration, and (2) the half band width shows anomalous changes with LiX concentration. Non-ionized LiClO4 species in alcohol coupled with the changes of solution structure are the major cause for this peculiar behavior.

Various properties of water and aqueous solutions are reviewed within the framework of the ‘strong/fragile liquids’ classification. The peculiar situation presented by pure water and dilute aqueous solutions, is discussed, then the more concentrated and easily glass-forming solutions involving salts, molecular components, and polymeric components are reviewed. In the electrolyte cases the properties of solutions in the glass-forming domain up to the ice-saturated limit prove to be those of very fragile liquids. This behavior is incompatible with the properties of pure water near the glass transition of vitreous ice (amorphous solid waters; ASW), supporting the notion that the latter is a distinct and separate phase of H2O. In the molecular solute cases, particularly with sugar components, the liquids appear to become stronger with increasing water content, whereas with water-plasticized polymers the position is not yet clear. Evidence on methacrylate polymers and proteins suggested that they may be rather strong. With this background the effects of solution fragility on the kinetics of longer time scale processes is discussed. In particular, the freezing of chemical reactions at temperatures well above Tg is considered in relation to the fluid (solvent) fragility, and accounted for in terms of a simple diffusion model.

Raman spectra of aqueous HX solutions (X = F, Cl, Br and I) were measured in botl: the liquid and glassy states. It is shown that the preresonance Raman effect is the major factor for the intensity increase in the Raman spectra with increase in halide concentration. The general spectral features are essentially the same as those for aqueous LiX solutions when the contributions of oxonium ions are excluded. The Raman bands of oxonium ions were observed better in the Raman spectra of glassy HX solutions.

Glass transition temperature ( T g ) of mixtures of alcohol (methanol, ethanol or 1-propanol) and aqueous LiCl solution were measured as a function of alcohol content. Anomalous T g behavior was observed for all the solutions. Phase separation (double glass transition phenomenon) was observed for the mixture of ethanol and aqueous LiCl solution. Hydrophobic interaction between water and alcohol molecules is considered to be responsible for the anomalous T g behavior.

The loss of nickel under cathodic polarization in molten NaNO3 increased with an increase in the quantity of electricity for the cathodic reaction. The formation of NiO was observed on the surface of the nickel after cathodic polarization. A large amount of powdered corrosion product consisting of NiO was detected in the NaNO3 salt after cathodic polarization. The cathodic polarization reaction and the products by the cathodic polarization reaction were examined in order to determine a mechanism for the cathodic corrosion of nickel in molten NaNO3. On the basis of the results it was proposed that the corrosion of nickel under cathodic polarization in molten NaNO3 occurred by a chemical reaction of nickel with NO2 and O2− which appeared to be cathodic products.

The loss of nickel under cathodic polarization in molten NaNO3 increased with an increase in the quantity of electricity for the cathodic reaction. The formation of NiO was observed on the surface of the nickel after cathodic polarization. A large amount of powdered corrosion product consisting of NiO was detected in the NaNO3 salt after cathodic polarization. The cathodic polarization reaction and the products by the cathodic polarization reaction were examined in order to determine a mechanism for the cathodic corrosion of nickel in molten NaNO3. On the basis of the results it was proposed that the corrosion of nickel under cathodic polarization in molten NaNO3 occurred by a chemical reaction of nickel with NO2 and O2− which appeared to be cathodic products.

Raman spectral changes associated with vitrification were measured for ZnCl2·4OROH solutions (ROH=methanol, ethanol and 1-propanol). Solvated ZnCl2 is the only major Zn-species in these solutions at room temperature while the dominant Zn-species stabilized in the glassy alcoholic solutions are ZnCl3−, ZnCl42− and [Zn(MeOH)6]2+ for the methanol solution, ZnCl2 and ZnCl3− for the ethanol solution and ZnCl2 for the 1-propanol solution. Together with Raman data for aqueous ZnCl2 solutions, the differences in the dominant Zn-species in the glassy alcoholic solutions are discussed in terms of the dielectric constants of solvents (water and alcohols).

The complex ion of the title molecule (+)589-[Co(C2H8N2)2(C12H12N2O4)](ClO4)3, has twofold symmetry and the absolute configuration is Λ. The seven-membered chelate ring of the 4,4′-dimethoxy-2,2′-bipyridine 1,1′-dioxide ligand adopts a chiral skew conformation of δ, which forms a lel structure in the complex ion. The dihedral angle between the two pyridine rings is 61.2 (2)°, and the O—Co—O bite angle is 91.3 (2)°. The ethylenediamine chelates take a δ-gauche conformation in the complex ion.

The title molecule, C 10 H 8 N 2 O 2 , lies on a crystallographic twofold axis. The dihedral angle between the planes of the pyridine groups is 67.5° and the non-bonded distance between the O atoms in the N-oxide groups is 3.046(2)A. Although the skew conformation of the skeleton is almost the same as that of the coordinated form, the dihedral angle is the largest among the corresponding values for the 2,2'-bipyridine 1,1'-dioxide complexes.

This paper describes a method for measuring the small current through the oxides on the order of 10/sup -20/ A or less using a floating gate MOSFET and the application results on flash memories with thin tunnel oxides. The method is based on accurate measurement of the threshold voltage of a floating gate MOSFET with no charge in the floating gate. We applied the method to flash memories to investigate the leakage current behaviour through thin tunnel oxides with very small areas (

The coordination of NO 3 - ions to Ln 3+ ions (Ln, rare earth) in Ln(NO 3 ) 3 -H 2 O-alcohol systems (Ln≡La, Gd, Yb; alcohol≡methanol, ethanol) was investigated by Raman spectroscopy. The fraction of NO 3 - ions coordinated to Ln 3+ ions decreases smoothly from La 3+ to Yb 3+ . The addition of alcohol to aqueous Ln(NO 3 ) 3 solution enhances the coordination of NO 3 - ions to Ln 3+ ions

Conjunctival goblet cells secrete mucus in response to cholinergic (muscarinic) agonists, but the underlying signaling pathways activated in this tissue are not well understood. Cholinergic agonists usually activate phospholipase C to produce inositol 1,4,5 trisphosphate and diacylglycerol. Inositol 1,4,5 trisphosphate increases the intracellular Ca(2+)concentration ([Ca2(+)](i)) while diacylglycerol activates protein kinase C (PKC). PKC and Ca(2+), either by itself or with calmodulin, activate cellular functions. Goblet cell glycoprotein secretion, our index of mucin secretion, was measured from pieces of rat conjunctiva with an enzyme-linked lectin assay using the lectin Ulex europaeus agglutinin I (UEA-I). UEA-I selectively recognizes high molecular weight glycoproteins secreted by the goblet cells. Increasing the [Ca(+)](i)with the Ca(2+)ionophore ionomycin stimulated glycoprotein secretion from conjunctival goblet cells. Cholinergic agonist-induced secretion was completely blocked by chelation of extracellular Ca(2+)and by the Ca(2+)/calmodulin-dependent protein kinase inhibitors KN93 and W7 as well as their inactive analogs KN92 and W5. Activation of classical and novel PKC isozymes by phorbol 12-myristate 13-acetate and phorbol 12,13-dibutyrate stimulated goblet cell glycoprotein secretion. When ionomycin and PMA were added simultaneously, secretion was additive. PKC isozymes were identified by Western blotting analyses with antibodies specific to nine of the 11 PKC isozymes (PKCgamma and zeta were not tested). All nine PKC isozymes were identified in the conjunctival epithelium. The cellular location of the PKC isozymes was determined by immunofluorescence microscopy. Goblet cells contained the classical PKC isozymes PKCalpha, -betaI and -betaII, the novel PKC isozymes PKCepsilon, -theta;, and - mu, and the atypical PKC isozyme PKCzeta. We were unable to determine if PKC activation is required for cholinergic-agonist induced secretion because the PKC inhibitors chelerythrine and staurosporine alone greatly increased secretion. We conclude that Ca(2+)plays a major role in cholinergic agonist-induced conjunctival goblet cell secretion, but this agonist appears not to use Ca(2+)/calmodulin-dependent protein kinases. We also conclude that activated PKC can stimulate goblet cell secretion and that seven different PKC isoforms are present in the goblet cells.

Raman measurements were carried out on glassy concentrated sulfuric acid ( R =3, 6 and 10, R =moles of water/moles of H 2 SO 4 ). It is shown that complete ionization of concentrated sulfuric acid is realized at low temperatures.

Luminescence, time-resolved luminescence, and decay-times were measured for uranyl ions doped in the improper-ferroelectric Rb2ZnCl4 crystal in order to investigate the incommensurate-commensurate phase transition mechanism involved. Luminescence spectra down to 11 K were identified as being due to two uranyl ion sites, I and II, with different spectral shapes and lifetimes. A strongly temperature dependent change of a thermal hysteresis-loop in luminescence intensity, shift and broadening was found for a substitutional site I in the vicinity of the INC-C phase transition temperatures. This is explained by pinning effects of impurity ions in luminescence which prevent a diffusion of discommensurations in the thermal equilibrium processes. This should result in the first observation of an anomalous luminescence memory effect in the ferroelectric phosphor.

Two years field experiments were conducted to evaluate the effects of placement and supplying patterns of soluble or controlled availability fertilizers (CAFs) on the N recoveries, growth and yield of dent corn (Zea mays L.). Grain yield of co-situs CAFs treatments were about 20% greater than that of conventional urea treatment in 1995, while there was no difference between these treatments in 1994, reflecting the differences in rainfall between the two years. The controlled N supply synchronizing with the N demands of dent corn increased the recovery of N fertilizer in any climatic conditions. Therefore single co-situs placement of suitable CAFs can increase fertilizer efficiency and achieve stable yield.

Two synthetic peptides 31 and 32 amino acids in length were prepared as deduced from a known amino acid sequence of penicillin-binding protein 2' (PBP2') of methicillin-resistant Staphylococcus aureus. Two monoclonal antibodies were generated from fused cells of myeloma cells and splenic cells of mice immunized with the synthetic peptides. Western blot (immunoblot) analysis demonstrated specific binding of the antibodies to PBP2' of a methicillin-resistant S. aureus strain. An immunoradiometric assay was developed by using these antibodies for simple detection of PBP2'.

To clarify the misunderstanding in the statements made in the above paper, it is shown that Raman OD stretching spectra of glassy aqueous tetraalkylammonium chloride are very similar to those of low-density amorphous D 2 O ice (LDA) despite the structural differences between LDA and glassy aqueous tetraalkylammonium chloride solutions.

Supercooling behavior of aqueous dimethylsulfoxide (DMSO) solution was investigated as a function of DMSO concentration and at high pressures. A linear relationship was observed for T(H) (homogeneous ice nucleation temperature) and T(m) (melting temperature) for the supercooling of aqueous DMSO solution at normal pressure. Analysis of the DTA (differential thermal analysis) traces for homogeneous ice crystallization in the bottom region of the T(H) curve for a DMSO solution of R=20 (R: moles of water/moles of DMSO) at high pressures supported the contention that the second critical point (SCP) of liquid water should exist at P(c2)= approximately 200 MPa and at T(c2)-100 degrees C (P(c2): pressure of SCP, T(c2): temperature of SCP). The presence of two T(H) peaks for DMSO solutions (R=15, 12, and 10) suggests that phase separation occurs in aqueous DMSO solution (Ror=15) at high pressures and low temperatures (-90 degrees C). The pressure dependence of the two T(H) curves for DMSO solutions of R=10 and 12 indicates that the two phase-separated components in the DMSO solution of R=10 have different liquid water structures [LDL-like and HDL-like structures (LDL: low-density liquid water, HDL: high-density liquid water)] in the pressure range of 120-230 MPa.

There are four molecules in a unit cell of the title compound, C 12 H 12 N 2 O 2 , and the structure of only half a molecule has been determined because of its twofold rotational symmetry. The dihedral angle between the two pyridine rings is 61.3° and the non-bonded distance between O atoms in the N-oxide groups is 2.96 A. The skew conformation of the skeleton is almost the same as that of the tetrakis(2,2'-bipyridine 1,1'-dioxide)-lanthanum(III) complex.