Bi Component Research Articles

Thermodynamics and the Segregation-Order Transformation in Liquid Na-Bi Alloys

The quasichemical approximation (QCA) has been applied to study the asymmetry observed in the concentration dependence of the thermodynamic properties of Na-Bi liquid alloys. The formation of a complex of the form Na 3 Bi has been assumed to calculate the concentration dependence of some thermodynamic properties, the long wavelength limit of the structure factors S CC (0), S NN (0) and S NC (0) and the Warren-Cowley short-range order parameter α 1 . The calculations indicate that with decreasing percentage of the more electronegative Bi component, there is an increasing tendency for phase separation. Size effect is negligible and thus we ascribe observed compound formation to electronegativity (EN) difference between Na and Bi. We expect that K, Rb and Cs-Bi liquid alloys would tend to be systems for which heterocoordination would dominate since in all cases the EN difference is larger. This deduction is in agreement with experimental observations.

Nicotine addiction in chronic schizophrenic inpatients

27) were adult neuroleptic-medicated inpatients with a DSM-III-R diagnosis of chronic schizophrenia (n = 22) or schizoaffective disorder (n = 5). Paired t tests revealed higher B! than NAART estimates for FSIQ (NAART m =97.2, BI m z 103.8; t[23] 2.63, p < 0.05), VIQ (NAART m -93.7, BI m = 103.2; t[23] =3.5, p < 0.05), but not PIQ. NAART and BI correlations with age, illness duration, education, and mental status (MS) revealed no significant associations. A trend between NAART and MS (r 0.37, p = 0.07) emerged. The possible NAART/MS relation suggested the NAART may be sensitive to cognitive deterioration. One possibility is that the ability to read/retrieve irregular words declines in schizophrenia, consistent with models of left hemisphere dysfunction. Studies with matched controls and nonchronic patients will determine if lower NAART scores reflect lower premorbid IQ or deterioration. As four of six BI components are demographic in nature and relatively independent of schizophrenia disease processes, these results may suggest that the BI is better suited for premorbid IQ estimation in schizophrenia.

Three-channel Lissajous' trajectory of the binaural interaction components of human auditory middle-latency evoked potentials

Three-channel Lissajous' trajectories (3-CLTs) of the binaural interaction component (BI) of auditory middle latency evoked potentials (AMLEPs) were derived from 14 normally hearing adults by subtracting the response to binaural clicks from the algebraic sum of monaural responses. AMLEPs were recorded in response to 65 dB nHL, rarefraction clicks, presented at a rate of 3.3/s. A normative set of BI 3-CLT measures was calculated and compared with the corresponding measures of simultaneously recorded, single-channel vertex-left mastoid and vertex-neck derivations of BI and of AMLEP to binaural stimulation (B). 3-CLT measures included: apex latency, amplitude and orientation, as well as planar segment duration, orientation, size and shape. The results showed seven main apices and associated planar segments (‘Be’, ‘Bf’, ‘Bg’, ‘Bh’, ‘Bi 1’, ‘Bi 2’ and ‘Bj’) in the 3-CLT of BI. Apex latencies of the BI 3-CLT were comparable to peak latencies of the vertex-left mastoid and vertex-neck AMLEP and BI records, both in their absolute values and in intersubject variability. Durations of BI planar segments were approximately 5.0 ms. Apex amplitudes of BI 3-CLT were larger than the respective peak amplitudes of the vertex-mastoid and vertex-neck BI records, while their intersubject variabilities were comparable. The lateralization of BI components may indicate asymmetric processing of binaural auditory input, or may be connected with anatomical asymmetry such as skull thickness. Preliminary analyses did not reveal a clear correlation between the lateralization of the BI component ‘Bi 2’ and the handedness of the subject. We suggest that BI components of AMLEP may be associated with the primary auditory cortex and subcortical ascending structures.

ゾル・ゲル法によるＢｉ系銅酸化物超伝導膜の作製に於ける出発組成と特性

Bi-Pb-Sr-Ca-Cu-O superconducting films were prepared on single MgO substrate by sol-gel method . As the starting solution, we used acetates-solutes butyric acid with the addition of aqueous ammonia . The films were prepared by repeating the process of coating and decomposition (at 700 C for 30 min) 3 or 5 times and by finally sintering at 855°C. for 12h . In the composition of BiaPbbSr2.0Ca2.2Cu3.2Oy (M=a+b, b=0.3a), M was changed 2.6, 2.8, 3.0, 3.2 and 3.4 and it was found that the optimum composition was M=3.2, and when the high-Tc phase amounted to 67% and Tc0 (the critical temperature of zero resistance) = 93 K . As a reason of the existence of optimum M value, there was evaporation of Bi and Pb components which brought about impurities such as (Sr, Ca)2CuO3 for small M(≤2.8) . On the other hand for large M (≥3.0), it gave rise to precipitation of impurities such as CuO. We used Atomic Force Microscope (AFM) in observing surface microstracture, and we could find the height difference without sputtering gold in SEM observation.

Three-channel Lissajous' trajectory of the binaural interaction components in human auditory brain-stem evoked potentials

The 3-channel Lissajous' trajectory (3-CLT) of the binaural interaction components (BI) in auditory brain-stem evoked potentials (ABEPs) was derived from 17 normally hearing adults by subtracting the response to binaural clicks (B) from the algebraic sum of monaural responses (L + R). ABEPs were recorded in response to 65 dB nHL, alternating polarity clicks, presented at a rate of 11/sec. A normative set of BI 3-CLT measures was calculated and compared with the corresponding measures of simultaneously recorded, single-channel vertex-left mastoid and vertex-neck derivations of BI and of ABEP L+R and B. 3-CLT measures included: apex latency, amplitude and orientation, as well as planar segment duration and orientation. The results showed 3 apices and associated planar segments (“Bd II,” “Be” and “Bf”) in the 3-CLT of BI which corresponded in latency to the vertex-mastoid and vertex-neck peaks IIIn, V and VI of ABEP L + R and B. These apices corresponded in latency and orientation to apices of the 3-CLT of ABEP L + R and ABEP B. This correspondence suggests generators of the BI components between the trapezoid body and the inferior colliculus output. Durations of BI planar segments were approximately 1.0 msec. Apex amplitudes of BI 3-CLT were larger than the respective peak amplitudes of the vertex-mastoid and vertex-neck recorded BI, while their intersubject variabilities were comparable.

Study of the electronic structure of Ba(Pb,Bi)O 3−δ single crystals

Changes in the electronic structures of BaPb x Bi 1− x O 3−δ( x = 0 and 0.05) single crystals are analyzed as a function of sev surface treatments. The untreated surface exhibits a relatively weak presence of spoiling phases, which expresses a weak reactivity of these compounds. The fractured surface is characterized by a double O line, a double Bi line and a single Ba line, while the reconstructed surface exhibits essentially one set of single lines. Ar + ion etching and surface oxygenation give rise to two additional O components and one additional Bi component. The evolution of the shape of the Bi line does not allow one to conclude about the presence of any bismuth disproportionation in BaBiO 3−δ.

The growth of bismuth and antimony overlayers on InP(110)

The adsorption of Bi and Sb on clean cleaved InP(110) surfaces has been studied with soft x-ray photoemission spectroscopy at the BESSY synchrotron radiation source in Berlin. Bi and Sb were deposited onto ultrahigh vacuum cleaved InP(110) surfaces at substrate temperatures of 300 K [room temperature (RT)] and 120 K [low temperature (LT)]. In this paper we focus on the evolution of the overlayer emission intensities as a function of coverage. Spectra of the Bi 5d and Sb 4d core level emission lines were taken from the submonolayer regime up to coverages of approximately 60 and 20 monolayers (ML) of Bi and Sb, respectively. The spectra were then deconvoluted using a core level fitting routine. In all cases, good agreement between the experimental and fitted curves was achieved by introducing two chemically shifted components of the Bi 5d and Sb 4d core level emission which are interpreted in terms of Bi(Sb)–substrate and Bi(Sb)–Bi(Sb) bonds. However, for RT deposition, the evolution of the Bi 5d and Sb 4d spectra is significantly different in the coverage range below 2 ML. In the Bi case the adatom–substrate component grows first, and only after about 0.5 ML is the Bi–Bi component observed. The two components have equal intensity at about 2 ML. In contrast, the two components in the Sb 4d spectra grow with equal intensity until 1 ML. The spectra for higher coverages for both systems are dominated by the component assigned to adatom–adatom bonds and the overlayer is found to be semimetallic. The LT spectra do not have the easily resolvable features seen in the RT spectra which may indicate that the growth is much more disordered. However, the overlayers at LT are more laminar. In addition, we present the band bending versus coverage behavior for the Bi/p-InP(110) interface, which is compared to that of Sb/p-InP(110).

Intra-ponto-mesencephalic recording of binaural interaction in human brain-stem auditory evoked potentials

Brain-stem auditory evoked potentials (BAEPs) were recorded at intraparenchymatous sites along a ponto-mesencephalic stereotactic penetration path in a patient with the rare condition of a ponto-medullary lesion which required biopsy but did not grossly alter scalp BAEPs. Click stimuli were applied either monaurally (with contralateral masking noise against acoustic cross-talk; conditions ‘R’, ‘L’) or binaurally (condition ‘RL’). A binaural interaction trace (‘BI’) was derived by subtracting the sum of the monaural from the binaural responses: BI = (RL) − (R + L). Despite failure to obtain significant BI components above noise level for scalp BAEPs, at the lower pons clearly discernible, multiphasic BI activity could be recorded beginning at the peak latency of scalp wave III and extending over approximately the next 4 msec. Its amplitude rapidly fell off with distance toward more rostral, mesencephalic recording sites. In relation to this positive finding, the equivocality among some of the previous studies on the detection of BI components in human scalp BAEPs is tentatively rephrased in terms mainly of a low signal-to-noise ratio and of functional peculiarities introduced by the respective stimulation protocols.

A NOTE ON GRAPHS WHOSE DESTRUCTIONS YIELD COMPLETE SUBGRAPHS

Abstract A connected graph G of order p =|V| and sise q =| E | is said to be (ai, bi)-destructible (with respect to Ei and Vi say) if ai,bi are integral factors of p and an ai-set of edges Ei exists whose removal from G results in exactly bi components isomorphic to Ki i.e. whose removal from G isolates the vertices in a bi-set Vi. The operation of removing Ei and Vi from G results in either O or a subgraph H of G and is called an (ai , bi)-destruction of G. In this paper we show that the only graphs whose every (ai,bi)- destruction results in a complete subgraph are K (1,2) and K4—e, where e e K4.

Segregation in garnet LPE

Abstract Growth reactions of liquid phase epitaxial iron garnet mixed crystal films can be classified thermodynamically according to the changes of chemical potentials of its components. By using a special experimental procedure, the interpretation of the growth parameter dependence of chemical composition of the LPE layers is considerably facilitated. Interfacial concentrations of rare earth ions, for example, can be evaluated using a minimum of a priori assumptions about the growth mechanism. The analysis of experimental results shows an increase of the chemical potential of the Pb, Bi, and La component in substituted yttrium iron garnet during crystallization (trapping), while for Pr in YIG the chemical potential is constant. The Bi incorporation was found to be not significantly dependent on the crystallographic orientation of the layer ((100), (110) and (111)), if the comparison was done for identical driving force at the interface.

Associations of platinum-group minerals of the Noril'sk copper-nickel sulfide ores

Significant variations in modes of occurrence and composition of platinum-group minerals in different types of ores of the Noril9sk deposits are described. In disseminated sulfide ores the main platinum-group minerals are represented by isoferroplatinum and cooperite whereas in massive ores a great diversity of palladium intermetallic compounds and tetraferroplatinum commonly occur. Pd and Pt sulfides, tellurides, and bismuthotellurides are characteristic of veinlet-disseminated and breccia ores.A short review of the platinum-group mineralogy shows that, in addition to platinum-group minerals commonly found in other copper-nickel deposits, the Noril9sk ores are characterized by: (1) a wide spectrum of platinum-group element partners (Sn, Pb, Cu, Bi, Fe, Ni, As, Sb, Te, Se, Ag) in the platinum-group minerals, (2) a large number of ternary compounds of Pd, Sn, and Cu, and (3) a wide distribution of Pd-Pb minerals.The textural features observed in the massive ores indicate that the platinum-group minerals formed at a late stage in the crystallization history of the ores. These textural features include metacrystals and veinlets of platinum-group minerals in the main ore-forming sulfides--pyrrhotite, chalcopyrite-group minerals, and pentlandite--and the close association of platinum-group minerals with galena, sphalerite, and Cl-bearing djerfisherite. Polymineral intergrowths of platinum-group minerals are also noted. Of great interest are zonal intergrowths of these minerals, testifying to the transformation of the earlier platinum-group minerals by reaction with a residual solution.Different conditions of formation are represented by different types of platinum-group mineral assemblages. These are distinguished as those crystallizing directly from a sulfide melt and represented by cooperite and isoferroplatinum in disseminated ores and those formed from the residual liquid enriched in Pt, Pd, Sn, Pb, As, Sb, Bi, Cu, Ag, Au, and volatile components represented by various intermetallic compounds of palladium in massive ores composed of chalcopyrite-group minerals.

Dependence of Magnetooptic Properties of MnBi Films on Component Ratio

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Electric Current System in the Undisturbed Magnetospheric Tail

Satellite measurements of the magnetic field B in the earth's tail indicate the existence of electric currents flowing inside the tail but outside the so‐called ‘Current’ or ‘neutral’ sheet. The Imp 3 data indicate that the density of these currents, although not insignificant, is smaller than the current density inside the ‘neutral’ sheet. Preliminary discussion of the effect of the polarity of the interplanetary magnetic field Bi on the tail geometry is presented. The ‘neutral’ sheet is systematically displaced northward if the polarity of Bi is positive (i.e., if Bi has a component directed away from the sun), but its average position is close to the plane Z = 0 if the polarity of Bi is negative. ((X, Y, Z) is the standard solar magnetospheric coordinate system.) The tail structure outside the ‘neutral’ sheet is not symmetric with respect to the plane Z = 0, even if the geomagnetic latitude of subsolar point (χ) is close to zero; i.e., the magnetic field in the part of the magnetotail where the X component of B is antiparallel to the X component of Bi is smaller than in the other part of the tail.

The cytochemistry of synaptic densities. I. An analysis of the bismuth iodide impregnation method

The affinity of BIUL (bismuth iodide impregnation, combined with uranyl acetate and lead hydroxide poststaining) to nerve ultrastructure is examined. Maximal electron microscopic contrast is seen in chromatin, ribosomes, inner and outer fuzz coats of membranes, and especially the membrane complexes at intercellular junctions. Basement lamina and osmiophilic leaflets of unit membranes attain low contrast properties. The BI component reacts with basic amino residues (in vitro studies), while U followed by L not only stains the acidic groups but is apparently bound to BI. Methylation and acetylation experiments support the notion that the high contrast of synaptic membrane complexes as demonstrated by the BIUL method may be related to the presence of high concentrations of anionic as well as cationic groups.