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排序方式: 共有1441条查询结果,搜索用时 15 毫秒
1.
2.
Masafumi Itoh Osamu Sakurada Minoru Hashiba Kouichi Hiramatsu Yukio Nurishi 《Journal of Materials Science》1996,31(12):3321-3324
An average shell volume occupied in the adsorption layer on alumina by a polyacrylic acid ammonium salts molecule (PAA) defined as the average area occupied by an adsorbed PAA on alumina multiplied by the average thickness of the water layer at the limit of thickening, has been calculated from the adsorbed amount of PAA and from the flow points of alumina in the presence of PAA of different molecular weights. A steric effect of the PAA dispersant on the dispersion of alumina resulted in a flow with no yield stress. This was due to the change of the extension of PAA in the adsorption shell from a sphere to an ellipsoid with a long axis which exceeded the effective distance that the van der Waals attraction force reaches at a molecular weight for the PAA of between 10 000–20 000. 相似文献
3.
Infrared (IR) detecting elements were prepared using positive temperature coefficient (PTC) thermistors with large temperature
coefficients of resistivity (α). Their compositions were denoted as Ba1−x
Sr
x
Nb0.003Ti0.997O3 + 1 mol % TiO2 + 0.07 mol %MnO (x=0, 0.2), and their temperature coefficients of resistivity were 78 and 50% K−1, respectively. Their IR sensing properties were measured under the self-regulating heating conditions, and were compared
with those of a detector with small α (18 % K−1). It was shown that large α was effective for controlling the element temperature by self-regulating heating and for improving
sensitivity. The responsivity,R
v
of the element withx=0.2 was 980 VW−1, and was as large as those of pyroelectric detectors. Expressions which normalize the sensitivity and the thermal time constant
were derived. From these expressions, criteria for improving some IR sensing properties were obtained. 相似文献
4.
Makoto Hino Minoru Hiramatsu Koichi Akiyama Hitoshi Kawasaki Masato Tsujikawa Makoto Kawamoto 《Materials and Manufacturing Processes》1997,12(1):37-46
A high powered YAG laser with kaleidoscope for surface modification was applied to the surface hardening of carbon steels containing 0. 18-0.54 wt% C without the absorbents, and the relationships between laser processing and surface hardening were investigated by hardness and microstructure. The structure of the hardened zone underwent complete martensitic transformation in all of the carbon steels tested, and its hardness increased with greater carbon content. Under identical irradiated conditions, the hardened zone expanded with increasing carbon content. A hardened zone extending from the surface to a depth of 1.0 mm was obtained at a laser power of 1.0 kW and a scanning speed of 1 mm/sec. It was found that in the surface hardening of carbon steels, a high powered YAG laser can be used to control the hardened zone by selecting the appropriate irradiation conditions, however, the hardened zone was affected by the assistant gas and the flow rate. 相似文献
5.
M Inaba K Inaba Y Fukuba S Mori H Haruna H Doi Y Adachi H Iwai N Hosaka H Hisha 《Canadian Metallurgical Quarterly》1995,25(5):1244-1248
We have previously found that thymic B cells, particularly thymic CD5+ B cells, show low responsiveness to the usual B cell stimulants such as lipopolysaccharide or anti-IgM plus interleukin (IL)-4, although they proliferate and produce antibodies after direct interaction with major histocompatibility complex class II-restricted T blasts. These findings raise the possibility that a CD40-CD40 ligand (L) interaction is involved in the activation of thymic B cells. In the present study, we therefore examine this possibility using CD40L-transfected Chinese hamster ovary (CHO) cells or anti-CD40 monoclonal antibody (mAb). When B cells in the spleen and peritoneal cavity were stimulated, they proliferated and produced immunoglobulin (Ig) in the presence of CD40L-CHO cells or anti-CD40 mAb alone. However, another signal delivered by IL-10 in addition to CD40L-CHO cells or anti-CD40 mAb was found to be necessary for thymic B cells to proliferate and secrete Ig. Other interleukins acting on B cells, such as IL-4, IL-5, and IL-6, had no effect on the activation of thymic B cells, which thus have unique characteristics not found in peripheral B cells. This report discusses the physiological significance of IL-10- and CD40-driven signals in the activation of thymic B cells. 相似文献
6.
When a fault occurs on transmission or distribution systems due to lightning or overvoltage, often an arc discharge occurs at the fault point. The arc discharge, which is caused by a fault current, has a high current, high temperature, strong light emission, etc., thus it sometimes causes heavy damages to electric power equipment. The arc discharge is influenced by the conditions around the arcs, i.e., gas, insulation materials, gap length, weather, etc. Also, the arc voltage along the arc column indicates the characteristics of the arc. If the voltage waveforms of the arcs caused by the fault on transmission or distribution systems are classified, it is possible to find the location and the equipment where the fault occurred. In this paper, the arc voltage data in 6-kV class XLPE cables and 6-kV class overhead lines are analyzed and an artificial neural network method is applied to classify the arc voltage waveforms. The results obtained from the six artificial neural networks developed show that the artificial neural network method is effective for classification of arc voltage waveforms if adequate input parameters are selected. 相似文献
7.
The authors propose a photodetector-amplifier circuit consisting of a bridge photodetector circuit and a CMOS differential amplifier, both monolithically integrated on a transparent substrate. A test circuit was fabricated using a-Si p-i-n photodiodes and poly-Si thin-film transistors on a quartz substrate. A clear effect of the differential amplifier was demonstrated in the test circuit. It is shown that the circuit performance can be controlled by changing the bias current of the differential amplifier. With a relatively low bias current on the order of 10-11 A, the circuit works digitally with output voltages either close to 0 V or V DD. The power consumption of the circuit is approximately 60 μW, which is low enough for use in two-dimensional arrays 相似文献
8.
9.
Minoru Ueno Satoshi Yamamoto Kenjiro Meguro 《Journal of the American Oil Chemists' Society》1974,51(8):373-376
Several salts of α,ω-sulfates, MO3SO(CH2)n OSO3M(n=12, 14, 16, 18, and M=Li, Na, and K) were prepared from the corresponding α,ω-alkane diols. The Krafft points of these
α,ω-sulfates with common counterion as estimated by electroconductivity measurements increased with the increase of the hydrocarbon
chain length, and the effect of the counterions on the Krafft points of the α,ω-sulfates with the same hydrocarbon chain length
was in the order : Li<Na<K. Solutions of the α,ω-sulfates, except disodium dodecanediol disulfate, showed two break points
corresponding to the first and second critical micelle concentration in each plot of the electroconductivity as a function
of the concentration. The existence of the second break point suggested that another aggregation of rearrangement of the existing
aggregates occurs in α,ω-sulfate solutions in addition to the usual micelle formation. The first and second break points of
α,ω-sulfates with sodium counterion decreased logarithmically with increasing total number of methylene groups. The relationships
were given as follows: log(first break point)=−0.138Nc−0.095; log(second break point)=−0.104Nc−0.251. The effect of the counterions
upon the break points of α,ω-sulfates with the same hydrocarbon chain length was in accordance with their positions in the
lyotropic series. 相似文献
10.
Koki Murano Tomoyoshi Shimobaba Atsushi Sugiyama Naoki Takada Takashi Kakue Minoru Oikawa Tomoyoshi Ito 《Computer Physics Communications》2014
We report fast computation of computer-generated holograms (CGHs) using Xeon Phi coprocessors, which have massively x86-based processors on one chip, recently released by Intel. CGHs can generate arbitrary light wavefronts, and therefore, are promising technology for many applications: for example, three-dimensional displays, diffractive optical elements, and the generation of arbitrary beams. CGHs incur enormous computational cost. In this paper, we describe the implementations of several CGH generating algorithms on the Xeon Phi, and the comparisons in terms of the performance and the ease of programming between the Xeon Phi, a CPU and graphics processing unit (GPU). 相似文献