This study examines the cytotoxicity of Super-Bond C&B (-&B), Super-Bond RC Sealer (SB-RC), MetaSEAL (Meta), and AH Plus Sealer (AH+). Freshly mixed and set materials (100 mg) were prepared in vitro and placed in cell culture medium (1 mL) for the working time and for 6 h, respectively. L929 cells seeded into 96-well plates at 5,000 cells/well were incubated with the eluted medium (200 µL) for 24 h. Cells cultured with medium alone served as the control. Cytotoxicity was evaluated by MTS assay and analyzed with ANOVA. In the freshly mixed group, the average ± SD (%) for cell viability were 66.0 ± 13.6, 55.5 ± 15.6, 10.6 ± 0.7, and 8.9 ± 2.2 for -&B, SB-RC, Meta, and AH+, respectively. In the set group, the average ± SD (%) for cell viability were 100 ± 21.9, 81.8 ± 38.5, 24.9 ± 7.9, and 23.6 ± 10.0 for -&B, SB-RC, Meta, and AH+, respectively. -&B and SB-RC are less cytotoxic than are Meta and AH+. (J Oral Sci 54, 213-217, 2012)

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直径10mm, 厚さ6mmの小円柱にねじを取り付けた小試験片を用いて, 引張・圧縮せん断・曲げ割裂・ねじりせん断接着強さを測定できる装置を考案し, 2種の歯科用接着剤(PEX, &B)の18-8ステンレス鋼(SUS304)に対する接着強さを測定した, PEX/SUS304の引張接着強さ(878±32kgf/cm²)と圧縮せん断接着強さ(576±84kgf/cm²)との差は高度に有意であったが, &B/SUS304の引張接着強さ(420±52kgf/cm²)と圧縮せん断接着強さ(405±55kgf/cm²)との差は有意でなかった.4点曲げ割裂接着強さは, PEX, &Bともに1000kgf/cm²以上に達し, 両者に有意な差は認められないなどの結果を得た.

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　圧縮せん断接着強さを測定する装置を試作して, 2種の歯科用接着剤(スーパーボンドC&B(以下 &Bとする), パナビアEX(以下PEXとする))とSUS 304との接着強さを測定し, 接着試験法について検討を加えた.次に接着ブリッジ用合金として可能性があると考えたNi-Cr-Co-Mo四元合金を溶製し, 鋳造したときの機械的性質, 耐変色性を調べ, この中から性質の優れた合金を選び, &Bとの圧縮せん断接着強さを測定した. &BとSUS 304の接着強さは, 接着後の放置温度により変化し, 60℃放置のとき約550 kgf/cm²に達した.20℃, 37℃に放置後4℃, 60℃の水中にそれぞれ120 sの熱サイクルを30回加えると接着強さは放置時よりかえって増加したが, 60℃放置では低下した.PEXとSUS 304の接着強さは, &Bにくらべ小さく, 変動係数は大きかったが, 放置温度による影響は少なかった.
　モリブデン量を15 wt%に一定し, コバルト5〜30 wt%, クロム10〜25 wt%, 残量をニッケルとしたNi-Cr-Co-Mo合金24種のうち優れた機械的性質および耐変色性を持つ合金組成は45±10Ni-20±2Cr-20±8Co-15Mo(wt%)と推定され, この範囲内にあるNo.15, 16, 17合金は, &Bと強固に接着し, 接着ブリッジ用合金として応用の可能性がある.

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This paper describes the morphological and rheological behavior of block copolymer solutions. The data cited here are concerned mostly with commercial styrene (S) and butadiene (B) copolymers of SB-diblock (Solprene 1205) and SBS-triblock (Kraton 1101) type. The emphasis is placed on the following two aspects: One is to compare the behavior of SB- and SBS- block copolymers dissolved in solvents such as n-tetradecane (C14) and n-decane, which are preferentially good to B-blocks but nonsolvent to S-blocks (we call them B-selective solvents). The other aspect is to describe and examine the nature of peculiar morphological and rheological transitions exhibited by changing temperature and concentration of /14 solutions.
The morphological features, the shape and size of microphase-separated domains exist in SB and SBS solutions, are essentially similar to each other, if the latter is regarded as an S-B/2 diblock copolymer. However, their rheology, especially in B-selective solvents, are entirely different, because S-cores are interconnected with B-blocks and therefore SBS-molecules form a quasinetwork structure in the SBS solutions. The quasinetwork structure imparts highly elastic and viscous properties to the SBS solutions. On the other hand, in the SB solution, SB-molecules form micelles with S-aggregates as the cores and soluble B-blocks as the cilia stabilizing the micelles. The /14 micelle systems exhibit viscoelastoplastic behavior (with yield stress). Upon raising temperature or decreasing concentration, the /14 solutions exhibit a transition from the viscoelastoplastic behavior to non-Newtonian (viscoelastic) and to Newtonian (viscoelastic) behavior (similar to a second-order fluid).
Small-angle-x-ray-scattering studies on the /14 solutions revealed that the rheological transition corresponds to the morphological transition from a simple-cubic macrolattice structure of the micelles to disordered suspension of the micelles and to homogeneous solution (at high temperatures) or a highly dilute suspension of the micelles (in low concentrations).

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直径10mm, 厚さ4mmの小円柱にねじを取り付けた小試験片を用いて, クロム量を5〜40mass%に変えたNi-Cr二元合金および純ニッケルのバフ研磨面および加熱酸化面に対する歯科用接着剤(PEX, &B)の引張・圧縮せん断接着強さを測定した.バフ研磨したNi-Cr二元合金に対するPEXの引張・圧縮せん断接着強さは, クロム量15%までほぼ直線的に増加し, 約500kgf/cm²となった. &Bの接着強さはクロム含有量に影響されず約410kgf/cm²であった.Ni-Cr二元合金を200〜600℃に加熱酸化させても接着強さは改善されないなどの結論を得た.

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A simple and reliable high-performance liquid chromatographic (HPLC) method was developed for the simultaneous determination of five hydroxyanthraquinones (aloe-emodin, rhein, emodin, chrysophanol, and physcion) in Rhubarb and experimental animal bodies. A Zorbax -18 column (250 mm × 4.6 mm i.d., 5 μm) and a methanol -0.5% acetic acid (85:15, v/v) mobile phase were used for the separation. The detection wavelength of a diode array detector (DAD) was set at 254 nm. Regression equations revealed a linear relationship (R² > 0.9996) between the mass of hydroxyanthraquinones injected and the peak areas detected by DAD. The detection limits (S/N = 3) ranged from 0.35 ng to 3.13 ng, and the recoveries ranged from 83% to 103% for different hydroxyanthraquinones. This method is simple, sensitive and suitable for the analysis of hydroxyanthraquinones in medicinal materials and pharmacological experiment samples.

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To quantitatively measure trace levels of bisphenol A (BPA) in infant urine, a simply improved high-performance liquid chromatography (HPLC)–tandem mass-spectrometry method was developed and validated. In the present work, a ZORBAX - column (2.1 × 30 mm, 3.5 μm) was used for trapping and isolating BPA from the HPLC mobile phase. The result showed that the trapping column can provide effective separation from the background BPA to the sample BPA. This method has a limit of detection (LOD) of 0.048 μg/L, spiked recoveries 85.4% (0.50 – 10.0 μg/L), and relative standard deviations of 1.8 – 15.9%. By using its low-LOD advantage, we firstly reported that Chinese infants (n = 48 with age <6 months) have been ubiquitously exposed to BPA (detection frequency of 93%) with an median level of 0.13 μg/L (ranging from below LOD to 5.04 μg/L).

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In order to overcome deficiencies for simultaneously determining felodipine (FDP) and metoprolol (MPL) with low recovery and low sensitivity, a new online SPE coupled with the liquid chromatography–tandem mass spectrometry (SPE-LC-MS/MS) method for the simultaneous quantitative determination of FDP and MPL in beagle dog plasma was established. The SPE extraction of FDP and MPL was performed on a Retain PEP Javelin column (10 × 2.1 mm, 5 μm), while the chromatographic separation was achieved on a ZORBAX -18 (50 × 2.1 mm, 3.5 μm) analytical column. Multiple reaction monitoring operated in the positive ion mode was adopted in MS detection, and the precursors to the product ion transition values of m/z 384/338.1, 268/74.2 and 436.2/207.1 were used to measure FDP, MPL and the internal standard (valsartan). The high throughput, accurate and sensitive method for FDP and MPL was validated and applied to the bioavailability research of FDP and MPL in beagle dogs.

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For elucidating the tread wear mechanism of studdless tires on the icy road, we have conducted, μ-S curve analysis which principally yields the relationships between the friction coefficient, μ, and the slip ratio, S, and deformation analysis of small rubber blocks located between the sipes.
Then the following results were obtained.
1) μ-S curve can be formulated by the following regression equation;
μ=(a•-)•exp(-S^d)+c•exp(S^e)
Where, μ is friction coefficient, S is slip ratio, and a, b, c, d and e are coefficients.
2) Resulted relationships between the shape of μ-S curve and tire performance on the icy road indicate that the tire performance enhances with loosening the sharpness of the μ peak shape.
3) The deformation analysis of small rubber blocks have reached an modified formula in which the degree of small rubber block deformation can be shown by an addition of bending deformation and the compression-shearing deformations. Using this formula, an amended equation of relationships between an inclined angle of the block and friction coefficient can be obtained, μ rock value obtained from dimensions of small rubber blocks of test tires with various number of sipes and from their modulus has corresponded with one obtained from substituting 100% for slip ratio in, μ-S curve regression equation. This verifies the effectiveness of the formula.

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As a fundamental study to develop a new process for eliminating detrimental antimony, recovering precious metals from the antimony-rich matte produced from the copper concentrate, and treating the occasionally generated speiss in nonferrous smelting processes, the phase relations in the Cu-Fe-S-Sb system saturated with carbon and the distribution of some minor elements between the phases in the miscibility gap, where three equilibrated phases of iron-rich alloy, copper-rich alloy and matte coexist, were investigated at 1200°C by using a quenching method.
The experimental results were compared with the results for the Cu-Fe-S-As-C system and discussed on the basis of activity coefficient of antimony in the matte phase at different matte grades. By utilizing the obtained data, material balance calculations concerning to the treatment of antimony-rich matte produced in copper smelting by adding the pig-iron was elaborated and also laboratory scale experiments using industrial matte were carried to corroborate the calculations. By using the phase separation, the cleaning of complex matte, the recovery of valuable copper, silver and gold into the copper-rich alloy and matte phases as well as the elimination of iron and an acceptable amount of antimony into the iron-rich alloy phase for discarding as a harmless and smaller deposit might be feasible.

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ポリ (エチレンテレフタラート) の重要な原料であるビス (2-ヒドロキシエチル) =テレフタラート (HOC₂H₄O₂C-C₆H₄-CO₂C₂H₄OH) を二三の有機溶媒中でテレフタル酸とエチレンオキシドから合成する反応をアルキルもしくはフェニルボスフィン, アルシン, スチビン (R₃X, X=P, As, Sb) の存在下に行い, これらの化合物の触媒作用について検討した. 反応中間体の単離および速度論的検討からボスフィン, アルシンではテレフタル酸, エチレンオキシドおよびR₃Xから成る三元錯体形成を経て生成するカルボン酸第四級塩 (R′COO (-) X⊕ (R₃) C₂H₄OH) が触媒となり, テレフタル酸のエステル化が起こっている. 一方, トリフェニルスチビンではカルボン酸第四級塩の生成は起こらず, エステル化反応も観測されなかった. テレフタル酸のエステル化速度は次の順に低下することを明らかにした. (n-C₄H₉) ₃P> (C₆H₅) ₃P>> (C₆H₅) ₃As>> (n-C₄H₉)

3Sb

, (

C₆H₅

) ₃Sb.

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As a fundamental study to develop a new process for eliminating detrimental elements and for recovering valuable ones from secondary Cu-Fe base alloys with a considerably high content of antimony, both the phase relations in a miscibility gap of the Cu-Fe-Sb system saturated with carbon and the distribution of some minor elements such as silver, platinum, cobalt, nickel and sulfur between two phases in the miscibility gap were investigated at 1473 K by a quenching method. The phase separation into copper-rich and iron-rich phases occurred when the Cu-Fe-Sb system was saturated with carbon. The antimony content in the copper-rich phase was very large compared with that in the iron-rich phase, and carbon was mostly distributed in the iron-rich phase. Cobalt and nickel were distributed preferentially in the iron-rich phase and platinum and sulfur were distributed almost evenly in both phases, while silver mostly in the copper-rich phase. The experimental results for the phase separation and the distribution of the minor elements were discussed on the basis of activity coefficients in the copper-rich and iron-rich phases and were compared with the results for the Cu-Fe-As system saturated with carbon. By utilizing this phase separation, recovery of valuable silver and copper into the copper-rich phase and elimination of less valuable iron into the iron-rich phase are feasible for treating the secondary Cu-Fe-Sb base alloys.

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Synopsis:
Effects of arsenic, antimony and tin on strength, recrystallization temperature and Snoek peaks of alpha iron were investigated. It was found that the increase in tensile strength caused by cold drawing became layer in the order, arsenic, tin and antimony addition. Effect of arsenic on the recrystallization temperature of alpha iron was not observed, on the contrary, antimony and tin affected the recrystallization temperature and it rised about 90°C. Changes in tensile strength and in electrical resistivity at liquid nitrogen temperature after aging the alloys quenched from 950°C were also investigated. The changes assumed to be due to precipitation were found in the alloys bearing more than about 0.25 atomic per cent antimony and tin, but were not found in the alloys containing less than 0.045 atomic per cent of antimony and 0.094 atomic per cent of tin, and less than 0.38 atomic per cent of arsenic.
The internal friction peaks owing to carbon and nitrogen were investigated by using the alloys containing about 0.25 atomic per cent arsenic, antimony and tin. In addition to the usual carbon and nitrogen peaks, abnormal peaks were observed on high temperature side of the usual peaks. Activation energies of the abnormal peaks were determined as 19.1 kcal/mol in Fe-As-N, 19.2 kcal/mol in Fe-Sb-N, 200 kcal/mol in Fe-As-C, 21.5 kcal/ mol in Fe-As-C, 21.2 kcal/mol in Fe--, and 22.5 kcal/mol in Fe-Sn-C.

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1998 年に噴火し，火山ガスの影響により全島避難している三宅島の切土法面植生に対して見取り調査を行った。三宅島は離島であり，国立公園域であるため外来植物である牧草の使用を控え在来種による法面緑化を進めようとする動きがある。しかしながら，在来種の国内採取種子は市場に流通していないため流通している中国産在来種種子を用いることになり，三宅島自生種の遺伝子攪乱を起こすおそれがある。この点を回避するために，過去の牧草による急速緑化箇所の植生推移状況を目視観察し，植生交代の実体を確認し，牧草使用の可能性について検討を行った。牧草は三宅島に自然分布しないため，遺伝子の攪乱に関する心配が無いため，むしろ外国産在来種よりも三宅島自生種に与えるインパクトは低いものと考えるからである。その結果，5 年程度でススキなどの周辺植生との交代が始まり，10 年以降は周辺植生から侵入したトベラなどの低木の生長が始まり，20 年程度で低木とススキの混在する状態となり自然回復が進むことが明らかになった。また，トベラの置苗吹付工を併用すると，5 年程度で同様の景観回復が可能となることが判明した。

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Many important problems in communication networks, transportation networks, and logistics networks are solved by the minimization of cost functions. In general, these can be complex optimization problems involving many variables. However, physicists noted that in a network, a node variable (such as the amount of resources of the nodes) is connected to a set of link variables (such as the flow connecting the node), and similarly each link variable is connected to a number of (usually two) node variables. This enables one to break the problem into local components, often arriving at distributive algorithms to solve the problems. Compared with centralized algorithms, distributed algorithms have the advantages of lower computational complexity, and lower communication overhead. Since they have a faster response to local changes of the environment, they are especially useful for networks with evolving conditions. This review will cover message-passing algorithms in applications such as resource allocation, transportation networks, facility location, traffic routing, and stability of power grids.

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