Orthogonal cutting tests and fretting tests were carried out by using such extreme pressure fluids as carbon tetrachloride, tricresyl phosphate and tri-n-butyl phosphate and a practical cutting fluid lard-kerosene mixture. The specimens were completely dipped in the fluids or the fluids were supplied over the surface of the specimen. All cutting fluids play roles for lubrication on the rear surface of chips. The fretting tests shown adaptability of the extreme pressure fluids for cutting the 7075-T4 alloy. Tricresyl phosphate (aryl series) and tri-n-butyl phosphate (alkyl series) of the phospholic esters have lubricating actions different from each other.

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In the hydrostatic journal bearing which requires an external resistance such as capillary or orifice, the load may be maintained on fluid film under pressure even though there is no relative movement between mating surfaces, and the fluid under pressure is supplied from external source to the load carrying fluid film as in the case of hydrostatic thrust bearing. This paper describes the characteristics of such a bearing having four rectangular pockets around the circumference. Particulary some theoretical investigations concerning the resistance, pocket throttle ratio and rigidity (i. e. stiffness) of this bearing are also reported to find out the designing factor of hydrostatic journal bearing under optimum operating condition.

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This paper presents the results of an investigation of the frictional effect on cutting forces in metal cutting. What is called the coefficient of friction especially in the case of metal cutting is actually the apparent coefficient of friction.
The real coefficient of friction is nearly constant, or independent of the rake angle of a tool at least. And it depends on the properties of the material, the condition of the tool surface, and the temperature of the contact surface, etc.
The theory of these phenomena is discussed in term of basic variables in chip formation. The fundamentals of chip formation are largely affected by the accuracy in measurement of cutting force under normal cutting conditions.
The primary requirement for the dynamometer is sufficient stiffness, and the second is high sensibility.
For this purpose, the authors made a three-dimentional tool dynamometer with a tubular tool holder. For measurement of interface temperature, a compensating circuit Is used to minimize the effect of parasitic electro motive force, induced by use of a lead dissimilar in composition to the carbide tip.
These results are shown graphically in Fig.5-10, then the considerations or discussions on the friction in metal cutting.
From these analyses, it can be concluded that the apparent coefficient of friction (μ) is defined by the real coefficient of friction (μ₀) and a function of the rake angle (α), as shown Eq. (5), (6).

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The cutting resistance value in turning decreased for the case hardening steel mixed with martensite in the ferrite matrix as compared with the normalized case hardening steel.
In the cutting at the low and intermediate speed, the micro-cracks were observed in chip of the steel mixed with martensite.It suggested that the cutting resistance value was decreased by the formation of the brittle fracture in the shear region of chip.
In the steel tempered for the softening of martensite, the cutting speed range where the built-up edge disappeared shifted to the high cutting speed side, and in this cutting speed range the side force increased.
In the cutting at the intermediate and high speed, the damaged layer (D₁) between the deformation flow layer (F_μ) and chip and the influence of the flow speed of chip (V_c) on the plasticity of F_μ, were important. The V_c and the difference of the hardness between D₁ and F_μ increased with an increase of shear angle of chip (φ) in the steel mixed with martensite more than the normalized steel.It was suggested that the cutting resistance value decreased with an increase of the plasticity in F_μ.Increase of the plasticity in F_μ resulted from the rise of the temperature due to the increase of theV_c and the hardness difference between D₁ and F_μ.

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A study has been made about behavior of belag for tool abrasion when Ca bearing free-cutting steel is machined.
(a) Composition of belag is different from that of inclusions and is varied by cutting speed.
(b) The limitation of cutting speed which makes the effect of belag lost is remarkably dominated by the type of inclusion and Ca itself also gives influence to the said limitation.
(c) Belag has barrier effect for crater abrasion and lubricating effect.
(d) Continuous supply of composition of inclusion (CaO-MnO-SiO₂-Al₂O₃) is necessary condition for keeping anti-abrasion of belag constantly in machining materials.

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Exploratory laparotomy was performed on a dog suspected of having idiopathic renal hematuria. Two catheters were inserted into the bilateral ureters, and hematuria from the left kidney was confirmed. The blood flow was occluded in the ventral and dorsal rami of the left renal artery in order to localize the site of hemorrhage. As hematuria disappeared when the dorsal ramus was occluded, the site of renal hematuria was localized to the area dominated by the dorsal ramus of the renal artery. As a result of ligating the dorsal ramus of the left renal artery in this dog, renal hematuria subsided, and the dog has shown a favorable course, to date, one year after surgery.

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In order to investigate the influence of second-phase particles on chip breakability of aluminum alloys, turning test for various wrought aluminum alloys were carried out with carbide inserts (K10) in dry and wet cutting conditions. In the materials, Al₂Cu, Mg₂Si, Al–Fe–Si system compound and eutectic Si were observed as second-phase particles. Chip breakability of materials which containing Al₂Cu or Si as second-phase particles were superior than that of materials with Mg₂Si or Al–Fe–Si system compound. This tendency was more prominent in wet cutting than in dry cutting. The Al₂Cu and Si particles on the machined surface were fractured by cutting tool in machining. It was estimated that those fractured second-phase particles acted as nucleus of chip breaking during machining. Moreover, the increase of the chip breakability in wet cutting was attributable to the promotion of fracture of Al₂Cu and Si particles due to the Rehbinder effect.

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Deep drawability, Baring ratio, tensile properties, textures and hardness change by deep drawing were examined for 2036 aluminum alloy specimens age-hardened under various conditions. Specimens aged at temperatures below 160° higher limiting drawing ratio (LDR) than those as quenched or fully annealed, whereas those aged above 180° lower LDR. LDR of age-hardened materials is shown to be correlated to total elongation and n value, but not to tensile strength and r value. Earing in age-hardened specimens is nearly same as in the fully annealed or as quenched ones. The obtained LDR values were compared with ones previously reported for 6061 and 7N01 alloys. 2036 and 7N01 alloys show the highest and lowest LDR, respectively when compared at the same tensile strength, total elongation, r and n values. LDR of age-hardened specimens of these three alloys are shown to be correlated to r_min value, and inversely correlated to the intensity of (200) diffraction parallel to the sheet.

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エポキシ樹脂硬化物では-70～-40℃領域にβ緩和と呼ばれる緩和挙動が観察される。この緩和は在来はビスフェノール骨格の運動によるともいわれ,ヒドロキシエーテル鎖の運動によるともいわれてきた。本報ではビスフェノール型,α,ω-ジオール型およびグリコール型エポキシ樹脂の3種を,構造を異にする2種の第一級アミンおよび2種の第三級アミンによって硬化し,構造上明らかにヒドロキシエーテル鎖の部分を生ずる系と,これを生じない系の緩和挙動を比較した。その結果,ヒドロキシエーテル鎖のような可動構造部分を含む硬化系のβ挙動は,それを含まない硬化系のβ緩和たとえば局所モード緩和などにこの可動構造部分の運動の影響が加わった複合緩和挙動と考えるべきことが明らかにされた。さらにヒドロキシエーテル構造を形成する硬化系と,これを形成しない硬化系の損失正接曲線の差から,ヒドロキシエーテル鎖のみの運動と考えられる新たな緩和ピークが推定された。この緩和ピークの高さとその位置はヒドロキシエーテル部分の濃度に依存することが明らかにされた。

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We isolated Streptobacillus moniliformis, the causative agent of rat-bite fever in humans, from the salivary gland of a pet rat postmortem. The isolate was a Gram-negative pleomorphic coccobacillus, which produced acid from glucose and showed enzymatic activities for eight items in the API ZYM system. The results were consistent with those of the reference strain, ATCC 14647^T, except for acid production from dextrin. Partial sequencing of 16S rRNA (1,440 bp) and gyrB genes (514 bp) of the isolate revealed similarities of 100% and 99.8%, respectively, to those of S. moniliformis in GenBank. Therefore, the isolate was identified as S. moniliformis. These results suggested the potential risk of rat-bite fever arising from pet rats in Japan.

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The grindability of carbon steel, e.g. cutting temperature, cutting forces, machined surface quality and chip formation are studied by a fundamental cutting experiment with a single fly tool method on several kinds of carbon steels, which have been heat treated under various conditions. It was found that the grinding temperature and forces are affected little by the hardness and the metallurgical structure, and that they are rather determined mainly by the grinding speed, and the thermal conductivity and carbon content of the work material. Also an increase of wear land of tool results in an increase in the grinding temperature and forces, which can be attributable to an increase of frictional force associated with the nardness of workpiece. It was further found that the effect of heat treatment and grinding speed is clearly observed on the formation of chip, which can be classified into four groups, thus contributing to the knowlege on grindability of steel.

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23種類の界面活性剤を用いてMHのタバコ腋芽抑制作用を指標に界面活性剤のアジュバント作用について検討した.
界面活性剤の化学構造と薬害については一定の関係は得られなかったが, タバコにおいては従来からいわれていたC₈～C₁₂を含む界面活性剤が, 必ずしもつねに高い薬害を示すとはいえないことがわかった. またアジュバント効果はC₁₂およびC_18:1を含む界面活性剤において局かった.
界面活性剤の物性とアジュバント作用については, 界面活性剤の薬害の出ない最高濃度および吸湿性に高い相関関係が認められたが, 表面張力, 接触角, HLB, pHには相関関係は認められなかった. またいくつかの保湿剤にも高いアジュバント効果が認められた.
以上の結果から, 従来の展着剤の効果つまり付着性, 湿展性, 懸垂性, 乳化性などに加えてアジュバント効果を期待する場合には, 高濃度で植物に薬害を与えず, 吸湿性にすぐれた界面活性剤を選ぶことが重要であることがわかった.

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抗酸化色素アスタキサンチンの天然唯一の供給源である微細藻ヘマトコッカスの生産性向上を目的とし，ホルモンの一種であるメラトニン（MT）の添加がHaematococcus lacustrisの細胞増殖とアスタキサンチンの生産性へ及ぼす影響を検討した。非生物的ストレスとして光強度の異なる条件下で比較したところ，強光条件下で，培養開始時にわずか1.0 mg L^－¹ のMTを添加することにより，対照区と比較してバイオマスとアスタキサンチンの生産量はそれぞれ11%と25%増強した。MTは低濃度で環境ストレス耐性を向上し生産性を増強するが，高濃度では細胞増殖を阻害した。これまでに報告されている増殖促進剤よりも，はるかに低濃度の添加で効果を発現することから，微細藻類培養におけるバイオスティミュラントとしてのMTの可能性が示唆された。

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ビスフェノール型,α ω-ジオール型およびグリコール型エポキシ樹脂をp,p'-ジアミノジフェニルメタン,α,ω-ジアミン類およびトリエチレンテトラミンによって硬化し,その力学的緩和挙動を調べ,セグメント構造との関連からその緩秘幾構を明らかにしようとした。
その結果これらの硬化物は170,80,-50および-130℃ 付近の領域に四つの緩和をもつ。ここではそれらをそれぞれα-,α-, β-およびγ-緩和とよぶことにする。これらの緩和のうちβ-緩和はこの硬化系のヒドロキシエーテル部分の運動に基づき,γ-緩和は4～6個以上のメチレン鎖もしくは2個以上のポリエチレングリコール鎖の運動によることを示した。

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Brillouin scattering spectra and the thermal expansion of SnCl₂·2H₂O were experimentally studied over a temperature range covering the isomorphous transition at −55°C (T_c). The frequency shifts of the longitudinal phonon show an anomaly at the phase transition temperature for q⁄⁄[100], [001] and [101] but not for q⁄⁄[010]. The thermal expansions along the crystalline axes a^*, b and discontinuity at T_c.

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The authors have reported that the machinability (lathe turning, drilling and sawing) of Type 304 austenitic stainless steel has been improved by the precipitation of hexagonal boron nitride (h-BN). In the present study, the influence of h-BN precipitation on surface roughness of Type 304 steel after lathe turning was investigated. Surface roughness was degraded with increasing the amount of boron addition, especially at lower cutting speed of 22 m/min. However, Type 304 steel with boron addition up to 0.05 mass % exhibited similar or better surface roughness compared to that of commercial Type 304 steel, and 0.1 mass % boron added Type 304 steel showed better surface roughness compared to that of Type 303 sulfur added free-cutting steel. Precipitation of h-BN enhanced the size of built up edge and degraded the surface roughness. On the other hand, increased Vickers hardness values due to solute nitrogen decreased the separation size of built up edge and improved the surfaced roughness.

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