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排序方式: 共有722条查询结果,搜索用时 15 毫秒
1.
Sachiyuki Hasegawa Kazuyuki Shimizu Takeshi Kobayashi Masakazu Matsubara 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(1):33-42
Repeated batch operation using two fermentors (RBTF) to penicillin fermentation was demonstrated by computer simulation to improve productivity. Three operation modes were compared: chemostat, repeated batch operation using a single fermentor (RBSF) and RBTF; in each case account was made of the lag period before growth. The simulated fermentor performances were assessed on the basis of the penicillin productivity and concentration; the simulation was based on published batch fermentation data. It was shown that RBTF was superior to RBSF and chemostat. The advantage of RBTF increased as the lag period became greater. 相似文献
2.
3.
The distribution of soap in the polymerization system for preparation of carboxylated polystyrene latexes has been investigated. The critical micelle concentration (CMC) for sodium dodecyl sulfate (SDS) in the polymerization system was determined by surface tension measurement to be 0.173 mmole/l. The solubility of styrene (St) in the aqueous phase of the polymerization system was determined by NMR measurement to be 4.52 mmole/l. It was confirmed by NMR measurement that at the concentration of SDS higher than the CMC, St is solubilized in the interior of the SDS micelles, and the concentration of solubilized St is almost proportional to the concentration of micellar SDS. From this relationship, the number and radius of SDS micelles containing solubilized St can be determined. 相似文献
4.
Recently, various robots with many degrees of freedom, such as rescue robots and domestic robots, have been developed and
used in practical applications. It is difficult to control such robots autonomously in real environments, because in order
to control the many degrees of freedom, we have to observe many states, calculate huge amounts of information, and operate
many actuators. In this study, we consider a flexible robot without sensors or controllers that can determine the inclination
of a slope and climb up the slope. In order to demonstrate the effectiveness of the proposed framework, we have developed
a prototype robot and conducted experiments. The result indicates that the robot could determine the inclination and climb
up a gentle slope autonomously. Thus, we have realized an autonomous robot that has no explicit sensors or controllers. 相似文献
5.
Although a number of studies on traditional Chinese medicine, such as qi-gong (QG), acupuncture (AC), moxibustion and Chinese herbal drugs, have been reported in recent years, there are few reports on human cerebral evoked potentials (EPs), especially relating only to QG and AC. In the present study, we examined the changes in EPs and electroencephalogram (EEG) by QG, and by AC stimulation to the point called "Zusanli" on the left lower leg, with one healthy male adult. 1. With regard to the effect of QG, significant changes in EP-components originated from the cortex suggest both facilitating and inhibitory effects of QG on the cortex. However, no significant changes in EP-components originated from the subcortex and no significant changes in EEG power% suggest that QG does not affect the subcortex. 2. With regard to the effects of AC, significant changes in EP-components originated from the cortex suggest facilitating and inhibitory effects of AC stimulation on the cortex. Furthermore, it is suggested that AC stimulation has few effects on the somatosensory and the visual pathways up to the cortex, while it has complicated effects on the auditory pathway up to the cortex. 相似文献
6.
Kazuyuki Maeshima Nanao Hayashi Tadayuki Murakami Fumiki Takahashi Hisashi Komae 《Journal of chemical ecology》1985,11(1):1-9
Chemical components stimulating oviposition bySitophilus zeamais in rice grain were isolated from rice bran and were found to be a mixture of ferulates, diglycerides, and free sterols. Oviposition preference of the species can be induced by synergistic action of these compounds. 相似文献
7.
众所周知,微生物,如藻类、细菌、霉菌(真菌和酵母)以及病毒可在物品的表面寄生和存活,尤其是当死角、粗糙的表面或微缝中有残存的营养物质时,微生物…在聚合物表面的生长可导致褪色、污渍、臭味、生物膜、交叉感染并最终降低机械强度,降低产品使用寿命。汽巴可为解决上述的问 相似文献
8.
Kazuyuki Wada Shigetaka Takagi Nobuo Fujii 《Analog Integrated Circuits and Signal Processing》1998,16(3):225-238
This paper proposes an automatic tuning system to adjust frequency characteristics of integrated continuous-time filters especially at high frequencies. Frequency characteristic deterioration of a filter using integrators with electrically controllable unity-gain frequencies can be easily evaluated and compensated even when they are affected by deviations of element values and parasitic elements. The compensation requires detection of both frequency and excess phase shifts of the integrators. Their two values are electrically detected by two detection systems usually used in the conventional frequency tuning system. The proposed system is stable, simple and easy to be implemented on an integrated circuit. As an example a 4th-order biquad bandpass filter with 10 MHz center frequency, 2 MHz passband width, and 0.5 dB passband ripples is designed using a bipolar process. Simulation results by SPICE show the effectiveness of the proposed system. 相似文献
9.
Kazuyuki Tsubone Noriko Uchida Kunio Mimura 《Journal of the American Oil Chemists' Society》1990,67(7):451-454
A series of new amphoteric surfactants having a phosphoric acid group, a tertiary amino group and a 2-hydroxyalkyl group, sodium 2-(N-2-hydroxyalkyl-N-methyl-amino)ethyl hydrogen phosphates (alkyl: n-tetradecyl, n-hexadecyl, n-octadecyl), were prepared by an addition reaction of 1,2-epoxyalkanes to N-methylaminoethanol, followed by the introduction of a phosphoric acid group and neutralization with sodium hydroxide. The structures of these compounds were confirmed by spectroscopy and elemental analysis. The solubility in solvents, Krafft point, surface tension, critical micelle concentration (CMC), occupation area of the molecule at the surface of aqueous solutions and foaming power were measured. It was shown that a 2-hydroxyethyl group in a long alkyl chain seemed to behave as a hydrophobic part. 相似文献
10.
Kazuyuki Ishikawa Naohiro Kameta Masaru Aoyagi Masumi Asakawa Toshimi Shimizu 《Advanced functional materials》2013,23(13):1606-1606