SrB4O2 (SBO) has recently received much attention as a wavelength-conversion material which can operate into the deepest ultraviolet wavelengths (125 nm). The utilization of SBO for semiconductor lithography and laser ablation requires fully transparent crystals. Here, we show the growth of SBO crystal fibers with near-stoichiometric composition by the mu-pulling-down method. SrB2xO3x+1 ceramics sintered with various values of x were evaluated by X-ray diffraction (XRD). The melting point of the SBO ceramics was measured by differential scanning calorimetry (DSC) as 1017 degrees C, and the heat of fusion was 63.3 J/g. Furthermore, we observed SBO crystal fibers grown with various x values by optical microscopy. As a result, even when the deviation from stoichiometric composition was +/- -0.1 mol % SrO (x = 2 +/- 0.004), SrB2O4/SrB6O10 appeared. Also, DSC curves of SBO ceramics exhibited only one melting peak. These results demonstrate that SBO shows no solid-solution width and that the stoichiometric composition is equal to the congruent composition. Furthermore, we succeeded in obtaining transparent SBO crystal fibers by growth with a stoichiometric composition. In contrast, since growth ridges including SrB2O4/SrB6O10 were formed on surfaces of the SBO single crystals, SBO crystal fibers grown with nonstoichiometric composition were opaque. We could explain the formation of growth ridges via compositional supercooling on rims.

Phase relation studies for ternary Cu-Fe-S system have been performed by author and some students. Their results are described as mainly phase diagrams. Some diagrams are already reported, but adds additional new data and new knowledge. Phase relations from 900 to 500°C were performed by evacuated silica glass tube method, and from 500 to 300°C were studied by thermal gradient transformation method under hydrothermal condition. Phase relations at 900, 800, 700, 600 and 500 by dry method were obtained and their phase diagrams are given in the Figs. 5, 6, 7, 8 and 9 and at 500, 400, 300°C determined by hydrothermal synthesis under 29 MPa (300 kg/cm), 98 MPa (1,000 kg/cm) and 196 Mpa (2,000 kg/cm) are also given in Figs. 10, 11, 12, 13, 14, 15 and 16.

High-form pentlandite of composition Fe4.93Ni4.06S8.01 first crystallizes by peritectic reaction between liquid and monosulfide solid-solution at 870 +/- 3 degrees C (865 +/- 3 degrees C for high-form pentlandite with Fe=Ni in at.%) in the Fe-Ni-S system; it forms a limited solid-solution from Fe5.08Ni3.93S7.99 to Fe3.81Ni5.24S7.96 including the ideal composition Fe4.50Ni4.50S8.00 at 850 degrees C. The solid solution grows rapidly to extend its field toward the Ni-rich side with decreasing temperature and connects with beta(2) (44.7 at.% S) in the Ni-S join at 806 +/- 3 degrees C (peritectic between liquid and Ni1-xS). Below the peritectic temperature, high-form pentlandite (metal-rich composition) crystallizes directly from liquid. This crystallization continues to the eutectic (746 +/- 3 degrees C for the high form with Fe=Ni) with decreasing temperature, and the high-form solid solution grows still more. Crystallization of the monosulfide solid-solution and high-form pentlandite solid solution from liquid finishes at 762 +/- 3 degrees C and 739 +/- 3 degrees C, respectively. The high-form pentlandite solid solution extended from the Ni-S join is maintained at 700 and 650 degrees C and coexists with monosulfide solid-solution and/or with liquid (870 to 739 degrees C), and/or with beta(1) or its solid solution (800 to 503 degrees C), and/or with gamma (762 to 579 degrees C).In geological processes such as the formation of Ni-Cu ore deposits, pentlandite can crystallize as the high form from liquid (sulfide magma) by peritectic and eutectic reactions at comparatively high temperatures from 870 to 739 degrees C (Fe-Ni-S system). Pentlandite is also produced by the breakdown of the high form at the pseudoeutectoid (or ternary eutectoid). Pentlandite can further be formed by exsolution from monosulfide solid-solution below 600 degrees C, and from the ternary beta(1) phase.

Ni-rich horomanite is found from the chalcopyrite-bearing (1.0-1.5 mode%) layer in the Kouyama gabbroic body, Hagi city, Yamaguchi Prefecture, western Japan and as second occurrence in the world. It occurs as inclusions in chalcopyrite interspaced with silicate minerals, vanadium-bearing magnetite and ilmenite. It is often associated with siegenite and is secondarily replaced by violarite. Chalcopyrite associating with Ni-rich horomanite commonly shows the polysynthetic twin. Analytical data for horomanite obtained by EPMA are Cu: 0.56-2.19, Fe: 23.01-25.32, Ni: 37.45-41.35, Co: 1.56-4.03 and S: 32.85-33.32 wt%. Their variations are small for inner grain or another grain. The atomic ratio of (Cu + Fe + Ni + Co): S correlates well with ideal formula of 9:8 for horomanite. In addition, Ni content in metal ratio for (Cu + Co): Fe: Ni (at%) ranges from 52 to 59 and is Ni-rich than that of original horomanite from the Horoman peridotite. Horomanite might be considered to be continuous solid solution ranging from 3.0 to 5.5 in terms of Ni(+Co) content. Therefore, general formula for horomanite is thought to be (Fe + Cu)6 − x(Ni + Co)3 + xS8(0 < x < 2.5).

Baumstarkite ideally AgSbS2, was found as aggregates of euhedral crystals in the Koryu mine, Hokkaido, Japan. The optical properties, chemical composition, and cell parameters of this mineral are presented. The compositional ranges are from 1.8 to 7.0 at.% As (7.4 to 28.2 mol.% AgAsS2). The unit cell of a sample with 10 mol.% AgAsS2 is triclinic, P (1) over bar with a 7.778(1), b 8.326(1), c 8.814(1) angstrom, alpha 100.90(1), beta 104.01(1), gamma 90.06(1)degrees, and V 543.2(1) angstrom(3); these values are in very good accordance with those of the type mineral as well as those of synthetic material.

An elongate field of high-form pentlandite solid-solution, Fe 5.65 Ni 3.35 S 7.85 , β 2 (Ni 4± x S 3 ), occurs in the system Fe–Ni–S at 650°C. This solid solution coexists with monosulfide solid-solution, β 1 (Ni,Fe) 3± x S 2 and γ (Fe,Ni). Pentlandite with a composition Fe 5.60 Ni 3.40 S 7.82 first appears as a stable phase at 625°C owing to the phase transition of the most Fe-rich high-form pentlandite with the same composition. It grows as a limited solid-solution, from Fe 5.64 Ni 3.36 S 7.82 to Fe 3.25 Ni 5.75 S 7.92 at 600°C and from Fe 5.68 Ni 3.32 S 7.85 to Fe 2.43 Ni 6.57 S 7.85 at 500°C owing to a continuous phase-transition, exsolution and breakdown (pseudoperitectoid and pseudo-eutectoid) of the high-form solid-solution and the exsolution and breakdown (pseudo-eutectoid) of β 1 . The compositional range of the solid solution is also increased by the exsolution of monosulfide solid-solution below 625°C. Pentlandite coexists with high-form pentlandite (625° to 503°C), monosulfide solid-solution (below 625°C), γ (below 617°C) and β 1 (579° to 484°C). High-form pentlandite still remains stable below 520°C, but breaks down to pentlandite, high-form godlevskite and β 1 at 503° ± 3°C and Fe 1.04 Ni 7.96 S 6.93 (eutectoid). Phase β 1 also breaks down to pentlandite, heazlewoodite and γ at 484° ± 3°C and Fe 0.26 Ni 2.87 S 2.00 (eutectoid). The assemblages with pentlandite and high-form godlevskite or heazlewoodite first appear at 568° ± 3°C or 498° ± 3°C, respectively. In this study, we show that pentlandite in the Ni–Cu ores can form at temperatures from 625° to 500°C or less owing to the phase transition, exsolution and eutectoid of the high-form pentlandite solid-solution, monosulfide solid-solution and β 1 . These are the primary phases that would crystallize from sulfide magma (liquid in the system Fe–Ni–S) between around 1000° and 750°C.

Horomanite and samaniite are found in the interstices among grains of silicate minerals in lherzolite from the Horoman peridotite massif, Samani-cho, Hokkaido, Japan. The mean analytical data for the horomanite, as determined by electron-probe micro-analysis (EPMA), are Cu: 0.43, Fe: 41.82, Ni: 23.76, Co: 0.52 and S: 33.29 for a total of 99.82 wt%. The empirical formula is (Fe5.77Ni3.12Co0.07Cu0.05)(Sigma 9.01)S-8.00. Crystallographic data for the horomanite acquired by X-ray single-crystal (precession) and powder (Gandolfi) diffraction methods. They revealed a tetragonal symmetry, space group P4/mmm, a = 8.707 angstrom, c = 10.439 angstrom, V = 791.4 angstrom(3), and Z = 4.The mean chemical composition of samaniite obtained by EPMA is Cu: 16.90, Fe: 34.60, Ni: 15.48, Co: 0.16, and S: 32.87 for a total of 100.01 wt%. The empirical formula is Cu-2.08(Fe4.84Ni2.06Co0.02)(Sigma 6.92)S-8.00. The crystallographic data for samaniite, which were obtained by X-ray single-crystal and powder-diffraction methods, are tetragonal symmetry, space group P4(2)/mnm, a = 10.089, c = 10.402 angstrom, V = 1058.9 angstrom 3, and Z = 4.

Aggregates composed of pentlandite, isocubanite and pyrrhotite occur in the basaltic andesite from Kasayama volcano, Hagi-city, Yamaguchi Prefecture, Japan. Fe content of pentlandite is slightly over the value of ideal formula (Fe4.5Ni4.5S)8. Isocubanite is close to the ideal CuFe2S3. The aggregates of these sulfides may have been crystallized from sulfide melt having composition of pentlandite solid-solution in silicate melt. After that, pentlandite solid-solution exsolved to pentlandite and Cu-Fe-S intermediate solid solution (iss). The iss also exsolved to isocubanite and pyrrhotite.

Sulfide blebs composing of bornite solid-solution, mooihoekite, isocubanite and pyrrhotite occur in andesite from the lava dome, Tarumai volcano, Hokkaido, Japan. The lava dome consists of two-pyroxene andesite. Some bornite solid-solutions are found as exsolution lamellae in mooihoekite which is originally crystallized as intermediate solid-solution (iss) in the Cu-Fe-S system at high-temperature, included in magnetite phenocrysts of the andesite. Isocubanite occurs closely associating with pyrrhotite included in orthopyroxene phenocrysts of the andesite, and is exsolved from the Cu-bearing pyrrhotite. Some bornite solid-solutions and mooihoekite are found in a ground mass as micro-crystals. The magnetite including mooihoekite and bornite solid-solution, and the orthopyroxene including pyrrhotite and isocubanite may be crystallized at different conditions. The crystallization temperatures are about 950 °C for the silicate melt including magnetite phenocrysts, and about 1150 °C for the orthopyroxene bearing silicate melt. Therefore, this andesite magma is thought to be formed by the magma mixing.

Isocubanite was found in spinel lherzolite xenolith with clinopyroxene-spinel symplectite from Ichinome-gata, Akita Prefecture, Japan. It occurs as two types; one is as exsolution lamella type in monosulfide solid solution (mss) and the other is a rim type observed around mss. The former type's chemical composition is very close to the ideal formula of isocubanite, CuFe2S3. The latter type has an intermediate composition between the ideal formula of chalcopyrite and that of isocubanite. The mss blebs including isocubanite lamellae associate commonly with orthopyroxene and clinopyroxene, sometimes with chromian spinel, and rarely with pargasite and clinopyroxene-spinel symplectite. The mss associating the rim type isocubanite occurs in orthopyroxene, clinopyroxene or olivine. The Ni-contents of mss associated with isocubanite are in the range from 19.3 to 25.8 of Ni/(Ni+Fe+Cu) in atomic%, and show the Cu contents vary from 0.07 to 0.45. Textures and chemical compositions of mss and isocubanite suggest that isocubanite occurred as an exsolution product from the originally formed monophase of mss, which had been crystallized during the metasomatic process in the upper mantle.

Sugakiite is found in the interstices among grains of olivine in the Horoman peridotite massif, Hokkaido, Japan. The mean analytical data (and range) for the mineral, as determined by electron-probe micro-analysis (EPMA), are Cu: 6.95 (6.21-7.91), Fe: 43.27 (42.75-44.03), Ni: 16.10 (15.25-17.02), Co: 0.18 (0.10-0.28), S: 33.04 (32.66-33.61). for a total of 99.54 (98.63-100.80) wt%. The empirical formula is Cu(Fe,Ni)(8)S-8. Crystal lographic data for the mineral were acquired by X-ray single-crystal (precession) and powder (Gandolfi) diffraction methods. They reveal a tetragonal symmetry, space group P4(2)/mnm, a 10.566 angstrom, c 9.749 angstrom, V 1088.4 angstrom(3), and Z = 4. The mineral is a product of high-temperature metasomatic adjustments after peridotite crystallization, and corresponds to CuFeNi2S8 synthesized at 850 degrees C by the dry method. Sugakiite is named in honor of Asahiko Sugaki (b. 1923), of the University of Tohoku, specialist in phase equilibria in sulfide systems.

AIMS:To investigate the requirement of outer membrane porins for osmotic adaptation at alkaline pH in Escherichia coli. METHODS AND RESULTS:Escherichia coli mutants deficient in ompC, ompF and both genes were constructed and the growth of these mutants was observed at alkaline pH. The growth rate of the mutant deficient in both ompC and ompF was slower than that of the wild type and mutants deficient in one of these genes under hyperosmotic stress at pHs above 8.0. The decreased rate was recovered when a cloned ompC was introduced to the mutant, but the growth recovery with a cloned ompF was partial. Such growth diminution was not observed at pHs below 8.0. CONCLUSION:OmpC and OmpF were shown to participate in hyperosmotic adaptation at alkaline pH in E. coli. SIGNIFICANCE AND IMPACT OF THE STUDY:This study is the first report to demonstrate that OmpC and OmpF are required for hyperosmotic adaptation at pHs above 8.0, but not below 8.0.

Sulfur (S) solubility is determined in silicate melts, in particular with low-FeO content coexisting with graphite. In a high FeO range (>10 mol %), the S solubility is strongly dependent on the FeO content in silicate melt, which is in good agreement with previous works. In an intermediate FeO range (1similar to10 mol %), the S solubility in melts with a multi-component system is higher than that in melts with a simple system. The SKalpha shift of the electron microprobe shows the dissolve sulfur is all sulfide. A positive dependence is observed between CaO and S content in the melt undoped with FeO, but the dissolved sulfur is sulfate. The relationship between melt composition, S content, and S oxidation state is discussed.

We have devised a new, simple and easy technique to measure the viscosity of hydrous silicate melts by combining an autoclave for melt hydration and the fiber elongation method for viscosity measurement. Using this, we measured the viscosity of hydrous rhyolitic melts whose water content ranges from 0.02 to 0.58 wt%. We observed a drastic decrease in viscosity against water content: 0.1 wt% water decreases the viscosity about an order of magnitude. Even when the water content is only 0.02 wt%, the viscosity decreased about half an order of magnitude. These results clearly demonstrate that the effect of water on viscosity should not be ignored even when it occurs as a trace constituent. We compared our experimental data with those derived from a non-Arrhenian viscosity model, which is considered to be applicable to calc-alkaline samples. This model succeeded in expressing the viscosity variation against water content but was unable to accurately predict the measured viscosity of liquids.

Phase equilibrium in the Cu-Fe-S system has been investigated for over 100 samples by the sealed silica tube method at 800degreesC. Bornite shows solid solutions ranging from (Cu4.70Fe1.30)(6.00)S-4.00 to (Cu7.43Fe0.00)(7.43)S-4.00, and those of pyrrhotite ranges from (Cu0.04Fe1.01)(1.05)S-1.00 to (Cu0.00Fe1.00)(1.00)S-1.00. The intermediate solid solution (iss) and the sulfide liquid exist in the central part of this system. The most important difference between the phase diagram obtained in this study with that reported by KULLERUD et al. (1969) is that the sulfide liquid is between bornite and pyrrhotite, and that the tie-lines between bornite and iss and between bornite and pyrrhotite are unstable. The new phase diagram of this system at 800degreesC is reported.

Phase relations along the join Fe4.5Ni4.5S8-Co9S8 in the system Fe-Ni-Co-S were investigated by the evacuated-silica-glass-tube method. Euhedral crystals of high-form cobalt pentlandite (Co9S8) and a member of the solid solution containing 50 mole % Co9S8 were also synthesized by both I-2 vapor-transport and NaCl-KCl flux methods. The phases produced in this study were examined by ore microscopy, SEM, EPMA, high-temperature X-ray diffraction and DTA. A continuous solid-solution (low form) between pentlandite and cobalt pentlandite transforms to a high-form solid-solution at temperatures from 615degrees +/- 3degreesC (pentlandite) to 831degrees +/- 3degreesC (cobalt pentlandite). Except for end-member compositions, there is a narrow two-phase field with both low- and high-form solid-solutions. The high-low inversion is reversible. High-form solid-solution melts incongruently to liquid and monosulfide solid-solution at temperatures from 865degrees +/- 3degreesC (high-form pentlandite) to 930degrees +/- 3degreesC (high-form cobalt pentlandite), and then remnant monosuffide solid-solution melts completely at temperatures from 982degrees +/- 5degreesC for (Fe,Ni)(1-x)S to 1069degrees +/- 5degreesC for Co1-xS. These lines of evidence suggest that in geological processes such as the formation of Ni-Cu(-Co) ore deposits, pentlandite, Co-bearing pentlandite and Ni-bearing cobalt pentlandite can crystallize as the high form by peritectic reaction between monosulfide solid-solution segregated first from liquid (sulfide magma) and residual liquid at relatively high temperatures around 800degrees to 900degreesC. Pentlandite (Fe4.5Ni4.5S8.0), cobalt pentlandite (Co9S8) and the member of the solid solution with 50 mole % Co9S8 (Fe2.25Ni2.25Co4.50S8.00) are cubic, Fi (3) over barm, with a equal to 10.0608(2), 9.9287(2) and 9.9925(2) Angstrom, respectively, at room temperature. On the other hand, the high forms have a primitive cubic (pc) cell with a equal to 5.335(2) Angstrom for Fe4.5N4.5S8.0, 5.171(2) Angstrom for Co9S8, and 5.251(2) Angstrom for the composition with 50 mole % Co9S8 at 850degreesC, corresponding to a/2 of the low form. The inversion of low- and high-form solid-solution is of order-disorder type, from supercell (low form) to subcell.