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31.
Effects of pressure and temperature on dyeing acrylic fibres with basic dyes in supercritical carbon dioxide 总被引:2,自引:0,他引:2
The dyeing of acrylic fibre with CI Basic Blue 47 has been investigated using an ammonium carboxylate perfluoropolyether as an auxiliary in order to perform the reverse micellar system in supercritical carbon dioxide media. The basic dye was satisfactorily solubilised in the interior of the reverse micelle in the system, and dyeability in the supercritical carbon dioxide media was excellent, even in the absence of a retardant and/or an acid. The optimum proton-rich condition for dyeing of acrylic fabric is performed in reverse micelle aggregates and the proton-rich water pool is suitable for dye uptake by the fibre even without the presence of additives. Changes in glass transition temperature of acrylic fibre in the carbon dioxide media also influence the dyeing behaviour of acrylic fabric. 相似文献
32.
Takahiro Sawada Yoshiyuki Kawazoe 《Science and Technology of Advanced Materials》2013,14(5-6):609-611
A direct computer simulation of reaction dynamics at the electronic excited states is not easy to perform, because nonadiabatic equations must be solved as a function of time. Here we present a simple simulation to integrate directly the time-dependent Schrödinger equation within the framework of the time-dependent density functional theory (for electrons) coupled with the Newtonian equation of motion (for nuclei). We find that a chemical reaction, 2LiH→Li2+H2, takes place by the doubly excitation. Along the reaction, a level crossing occurs automatically between the highest occupied and lowest unoccupied levels. The simulation demonstrates a mechanism for relaxation for the reactions driven by doubly excitation: electronic excited state changes smoothly into the electronic ground state leaving a kinetic energy of the atoms. 相似文献
33.
Optimal Digital Controller Design for a Servo Motor Taking Account of Intersample Behavior 下载免费PDF全文
A continuous‐time plant with a discretized continuous‐time controller does not yield stability if the sampling rate is lower than some certain level. Thus far, high‐performance electronic control has made use of expensive hardware needed to implement discretized continuous‐time controllers; low‐cost hardware generally does not have a sufficiently high sampling rate. This technical note presents results comparing performance indexes with and without intersample behavior, and provides some answers to the question of how a low‐specification device can control a plant effectively. We consider a machine simulating wafer handling robots, which is an electromechanical system driven by a direct drive motor, at a semiconductor factory. We illustrate the controller design for the robot with and without intersample behavior, and present simulations and experimental results using these controllers. Taking intersample behavior into account proves to be effective in improving control performance and makes it possible to choose a relatively long sampling period. Controller design in terms of the performance index with intersample behavior makes it possible to deal with situations in which a sufficiently short sampling period may not be employed, and freedom of controller design may be widened, especially regarding the choice of the sampling period. 相似文献
34.
H. Endo A. Netchaev K. Yoshimura K. Arie M. Yamadate T. Sawada H. Ninokata 《Progress in Nuclear Energy》2000,37(1-4):291-298
Against fossil fuels, the nuclear energy is the only alternative energy source in the next century. Such energy source as the future nuclear power plant is expected to meet the following requirements. First, high temperature output for the multiple energy conversion capability as the electricity generation and the production of alternative fuels (hydrogen), which can be used widely in transportation systems. Second, the capability for siting close to the energy consumption area without onsite refueling. Third, the capability for nuclear fuel breeding and incineration of long-lived fission products, and fourth, the harmonization between active and passive safety features. This paper describes the basic concept of the Multipurpose liquid metallic-fueled Fast Reactor system (MPFR), which satisfies all mentioned requirements with introducing the U-Pu-x (x: Mn, Fe, Co) liquid metallic alloys for the fuel. We can obtain such characteristics as high operational temperature of the reactor (between 550 °C and 1200 °C) and elongation of the core operational lifetime by the inherent fission product separation in the liquid fuel by using these alloys. The enhanced self-controllability is achieved by the thermal expansion of liquid fuel; and the re-criticality phenomenon at the core compaction events can be eliminated by discharging of the liquid fuel from the core. 相似文献
35.
Shoji Seki Mami Iwasaki Hiroto Makino Yasuhito Yahara Yoshitaka Miyazaki Katsuhiko Kamei Hayato Futakawa Makiko Nogami Nguyen Tran Canh Tung Tatsuro Hirokawa Mamiko Tsuji Yoshiharu Kawaguchi 《International journal of molecular sciences》2022,23(7)
Intervertebral disc (IVD) diseases are common spinal disorders that cause neck or back pain in the presence or absence of an underlying neurological disorder. IVD diseases develop on the basis of degeneration, and there are no established treatments for degeneration. IVD diseases may therefore represent a candidate for the application of regenerative medicine, potentially employing normal human dermal fibroblasts (NHDFs) induced to differentiate into nucleus pulposus (NP) cells. Here, we used a three-dimensional culture system to demonstrate that ectopic expression of MYC, KLF4, NOTO, SOX5, SOX6, and SOX9 in NHDFs generated NP-like cells, detected using Safranin-O staining. Quantitative PCR, microarray analysis, and fluorescence-activated cell sorting revealed that the induced NP cells exhibited a fully differentiated phenotype. These findings may significantly contribute to the development of effective strategies for treating IVD diseases. 相似文献
36.
Makoto Tanaka Mikio Taguchi Tsuysohi Takahama Toru Sawada Shigeru Kuroda Takao Matsuyama Shinya Tsuda Akio Takeoka Shoichi Nakano Hiroshi Hanafusa Yukinori Kuwano 《Progress in Photovoltaics: Research and Applications》1993,1(2):85-92
A new solar cell structure named HIT (Heterojunction with Intrinsic Thin layer) has been developed based on new artificially constructed junction (ACJ) technology. In this structure a non-doped a-Si thin layer was inserted between the p(a-Si)/n(c-Si) heterojunction, improving the output characteristics and achieving a conversion efficiency of 18.1%. This structure was applied to cast polycrystalline silicon solar cells of a practical size. A high conversion efficeincy of 13.6% was obtained with a cell size of 10 cm × 10 cm using various technologies, including hydrogen plasma passivation. 相似文献
37.
Epigenetic changes influence various physiological and pathological conditions in the human body. Recent advances in epigenetic studies of the skin have led to an appreciation of the importance of epigenetic modifications in skin diseases. Cutaneous sarcomas are intractable skin cancers, and there are no curative therapeutic options for the advanced forms of cutaneous sarcomas. In this review, we discuss the detailed molecular effects of epigenetic modifications on skin sarcomas, such as dermatofibrosarcoma protuberans, angiosarcoma, Kaposi’s sarcoma, leiomyosarcoma, and liposarcoma. We also discuss the application of epigenetic-targeted therapy for skin sarcomas. 相似文献
38.
Natsuko Saito-Sasaki Yu Sawada Motonobu Nakamura 《International journal of molecular sciences》2022,23(3)
Inflammation is an essential action to protect the host human body from external, harmful antigens and microorganisms. However, an excessive inflammation reaction sometimes exceeds tissue damage and can disrupt organ functions. Therefore, anti-inflammatory action and resolution mechanisms need to be clarified. Dietary foods are an essential daily lifestyle that influences various human physiological processes and pathological conditions. Especially, omega-3 fatty acids in the diet ameliorate chronic inflammatory skin diseases. Recent studies have identified that omega-3 fatty acid derivatives, such as the resolvin series, showed strong anti-inflammatory actions in various inflammatory diseases. Maresin-1 is a derivative of one of the representative omega-3 fatty acids, i.e., docosahexaenoic acid (DHA), and has shown beneficial action in inflammatory disease models. In this review, we summarize the detailed actions of maresin-1 in immune cells and inflammatory diseases. 相似文献
39.
It was found that thin film devices derived from SnO2 sols by spin-coating method showed unique thermal behavior of electric resistance in air involving a temperature region where resistance was independent of temperature. The temperature independent resistance region extended up to 400 °C, replacing a region of temperature-conventionally dependent resistance, as film thickness increased. Such unique behavior of resistance was observed also for a brush-coated device but not for screen-coated thick film devices or disk-type device, suggesting that the absence of mechanical forces applied during device fabrication favored the occurrence of the unique behavior. It was shown that the unique behavior could be well accounted for by postulating a combination of electron tunneling transport and conventional migration transport. Calculation of tunneling probability based on a simple model allowed estimating that electron tunneling transport can take place between oxide grains with a probability of 0.01 or larger if a gap in between is narrower than 0.01 nm. 相似文献
40.
Numerical simulation of micro-nozzle and micro-nozzle-array flowfield characteristics 总被引:1,自引:0,他引:1
Preliminary numerical simulation using a Direct Simulation Monte Carlo (DSMC) method was conducted to elucidate the internal flowfield and external plume characteristics of micro-single-nozzles and micro-nozzle-arrays, since these small-sized nozzles generally undergo a severe viscous loss due to the low Reynolds numbers. This study also contains the investigation on optimization of the geometry and configuration of the micro-nozzles and micro-nozzle-arrays to achieve the improved propulsive performance. Typical sizes of each rectangular nozzle element were 0.1 mm in throat height, 0.36 mm in exit height, and 0.35 mm in length of the divergent part. For the micro-single-nozzles, calculated specific impulses were fairly in good agreement with our previous experimental data, showing a poor nozzle efficiency due to the viscous loss of low Reynolds number. Also, mechanisms of exhaust jet interaction of multi-nozzle-array jets, bringing a significant improvement in thrust performance, were investigated. As a result, it was shown that pressure and temperature increased at the exit and jet boundaries, and then the exhaust multi-jets were not expanded after the exit, or rather being confined, showing possibilities to realize the higher propulsive performance due to the augmented effect of the pressure thrust. 相似文献