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排序方式: 共有453条查询结果,搜索用时 15 毫秒
91.
Kerr-lens mode-locked Cr:LiSrAlF/sub 6/ lasers are demonstrated with various prism pairs based on a recalculation of the condition for compensating the intracavity dispersion. The minimum pulse duration is 9.9 fs, which is the limit for ordinary nonchirped dielectric mirrors. To develop an efficient diode-pumped Kerr-lens mode-locked Cr:LiSAF laser, diode-pumping geometry is also discussed. 相似文献
92.
93.
Yuji Sasaki Ryo Yoshimitsu Syouhei Nishihama Yuma Shimbori Hidenobu Shiroishi 《分离科学与技术》2017,52(7):1186-1192
A new extractant biuret(C8) is synthesized and tested for solvent extraction of hard acid metals, for example, actinides, and soft acid metals. This compound has a central frame similar to that of malonamide but with an additional amino functional group introduced into the central framework; in this case, both the amidic oxygen atoms and the amino nitrogen atom may bond with metals. We found that both hard and soft acid metals can be extracted from nitric or perchloric acids to n-dodecane using biuret(C8). It is clear that D(Pd, Pu, U) values of approximately 100 can be obtained using 0.1 M biuret(C8)/n-dodecane. 相似文献
94.
S. Isobe F. Zuber K. Uemura A. Noguchi 《Journal of the American Oil Chemists' Society》1992,69(9):884-889
Transport of material in a single-screw press depends mainly on friction between the material and the barrel’s inner surface
and the screw surface during screw rotation. Thus, a solid core component, like seed hulls, is often necessary to produce
the fraction. This sometimes causes excess frictional heat, large energy consumption and oil deterioration. Furthermore, if
single-screw presses are not configured with breaker bars or other special equipment, they provide inadequate crushing and
mixing.
A twin-screw oil press can be expected to solve these problems because of the higher transportation force, similar to a gear
pump, and better mixing and crushing at the twin-screw interface. A twin-screw press (screw diameter=136 mm, length/diameter=6.5,
screw speed 15–100 rpm, feed rate=50–150 kg/h) was designed with partially intermeshing and counter-rotating screws and was
tested on dehulled sunflower seed. The results were compared to a single-screw lab-scale press. Dehulled sun-flower seed (wt,
6.0%; oil, 58.6%) without pretreatments (crushing or cooking) gave 93.6% oil recovery with the twin-screw press, in contrast
to 20% oil recovery with the single-screw press. The oil expressed with a twin-screw press had less foreign material than
the oil from the single-screw press. Other properties of the oil were also good. Energy consumption of the twin-screw press
was more efficient. All results suggested that oil production from dehulled sunflower seed with a twin-screw press is highly
efficient. 相似文献
95.
A.P. Rubshtein I.Sh. Trakhtenberg E.G. Volkova A.B. Vladimirov A.G. Gontar K. Uemura 《Diamond and Related Materials》2005,14(11-12):1820
Hardness, elastic modulus, internal stresses and friction coefficients were measured in CN0 ≤ x ≤ 0.5 coatings (1–3 μm). The dependence of these parameters on nitrogen concentration can be applied in the practical coatings. The structure investigations show that the domain amorphous matrix mixture consists of CNx ≤ 0.1 and CN0.5. Such structure allows understanding the dependence of the CN0 ≤ x ≤ 0.5 coatings properties on nitrogen concentration. Through the structure, the coating properties of CN0 ≤ x ≤ 0.5, depend on the nitrogen concentration. 相似文献
96.
Yasuo Hatate Yoshimitsu Uemura Mitsunobu Migita Yoshinobu Kawano Yasuhiko Tanaka Kazuya Ijichi D.F. King 《Chemical Engineering Communications》1991,101(1):39-44
A semi-cylindrical fluidized bed of 15 cm internal diameter, equipped with a transparent flat glass plate for the front wall, was employed to visually observe bubbles in the bubbling to slugging transition regime and in the slugging regime. Five kinds of perforated distributors were used to investigate the effect of distributor type on the bubble size and the bubble rise velocity. The average bubble size was not affected by distributor type in these flow regimes, and could be predicted by Darton et al's correlation (1974)of hole number 22. In other words, this comes from the inapplicability of the correlation to the slugging regime. The bubble rise velocity agreed well with Allahwala et al's correlation (1979) and was not affected by the type of distributor. 相似文献
97.
In the work, investigation of the features and operation regimes of sputter enhanced ion-plasma source are presented. The source is based on the target sputtering with the dense plasma formed in the crossed electric and magnetic fields. It allows operation with noble or reactive gases at low pressure discharge regimes, and, the resulting ion beam is the mixture of ions from the working gas and sputtering target. Any conductive material, such as metals, alloys, or compounds, can be used as the sputtering target. Effectiveness of target sputtering process with the plasma was investigated dependently on the gun geometry, plasma parameters, and the target bias voltage. With the applied accelerating voltage from 0 to 20 kV, the source can be operated in regimes of thin film deposition, ion-beam mixing, and ion implantation. Multi-component ion beam implantation was applied to α-Fe, which leads to the surface hardness increasing from 2 GPa in the initial condition up to 3.5 GPa in case of combined N(2)-C implantation. Projected range of the implanted elements is up to 20 nm with the implantation energy 20 keV that was obtained with XPS depth profiling. 相似文献
98.
Nozomu Nanato Takahiro Inoue Satoru Murase Gen Nishijima Katsunori Tamakawa Munenori Amaya Yoshifumi Uemura 《低温学》2012,52(7-9):321-324
When a quench occurs in a superconducting magnet, excessive joule heating may damage the magnet. We have presented the quench protection system based on an active power method. Our previous quench protection tests have been carried out for small superconducting magnets whose self inductances are less than several hundred mH to verify principles of our proposed system. In this paper, we present experimental results of quench protection tests of a cryocooler cooled 6 T NbTi superconducting magnet (self inductance 15.5 H), which is a commercial size magnet made by Tamakawa Co., Ltd. We confirmed that our proposed system could inhibit the maximum temperature of the superconducting magnet (initial temperature 4.3 K) after the quench to less than about 44 K at operation magnetic field 5.5 T. Experimental results suggest that our proposed system is useful for practical used superconducting magnets. 相似文献
99.
A p-nitrophenyl-α-D -glycopyranoside-hydrolyzing oligo-1,6-glucosidase (dextrin 6-α-glucanohydrolase, EC 3.2.1.10) of a caldoactive Bacillus sp. KP 1228 capable of growing at 51–82°C was purified to homogeneity. The molecular weight was estimated as 140,000. The enzyme consisted of two identical subunits each comprising a threonine residue at the NH2-terminus. The enzyme was most active at 85°C and pH 5.1, and stable for 10 min up to 85°C at pH 6.8. The enzyme had no antigenic determinant common to oligo-1,6-glucosidases from Bacillus cereus ATCC 7064 (mesophile), Bacillus coagulans ATCC 7050 (facultative thermophile) and Bacillus thermoglucosidasius KP 1006 (DSM 2542) (obligate thermophile). A strong correlation between the increase in proline content and the rise in thermostability of these 4 proteins was observed. 相似文献
100.
In this paper, the voltage dynamics of induction motor loads up to some ten seconds are discussed in terms of a linearized model. It is generally recognized that the dynamics of a power system load mainly originate from the induction motor dynamics constituting the load. Aspects of the voltage dynamics of induction motors are analyzed with respect to machine constants. The results show that small and medium-sized induction motors have dynamics that can be well approximated at the first order, thus partly accounting for the fact that most feeders indicate first-order dynamics 相似文献