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排序方式: 共有1122条查询结果,搜索用时 15 毫秒
91.
92.
Phase relations associated with the aluminum blast furnace: Aluminum oxycarbide melts and Al-C-X (X=Fe,Si) liquid alloys 总被引:2,自引:0,他引:2
Harumi Yokokawa Masao Fujishige Seiichi Ujiie Masayuki Dokiya 《Metallurgical and Materials Transactions B》1987,18(2):433-444
The thermodynamic properties and the phase relations were evaluated and estimated for the Al-O-C, Al-Si-C, and Al-Fe-C systems
which are important to understand the chemical behavior in an aluminum blast furnace. The mixing properties of binary liquid
alloys, including metal-carbon systems, were represented by the Redlich-Kister equation. The properties of liquid Al−C and
Si−C alloys were estimated so as to be consistent with their phase diagrams. The coefficients of Al−Fe and Fe−C liquids were
evaluated from reported values for activity and enthalpy. The extrapolation to the higher order systems was made by Maggianu's
method. The aluminum oxycarbide melt was represented by a subregular solution model. In the Al-O-C system, liquid alloy/oxycarbide
melt equilibria were calculated and compared with earlier experimental results and estimates. Attempts were made to clarify
the volatilization of aluminum oxycarbide melts, and also the carbidation of liquid aluminum alloys. An empirical correlation
between the first terms of the Redlich-Kister equation for the enthalpies and the excess entropies was discussed. 相似文献
93.
Masao Taki 《IEEJ Transactions on Electrical and Electronic Engineering》2016,11(6):683-695
Research works on bioelectromagnetics in Japan are reviewed with a focus on the efforts devoted to the issue of human protection from electromagnetic field (EMF) exposures. History of this issue in Japan is briefly reviewed first for all EMF spectra. Then research works on radiofrequency (RF) EMF are summarized in more detail. The RF studies reviewed are mainly conducted in the framework of research program by the Ministry of Internal Affairs and Communications (MIC) started in 1997. Because of this program, collaborations between biology/medicine and engineering have been promoted. The results consistently show no evidence against the safety of RF‐EMF within the exposure levels of internationally accepted guidelines. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
94.
Itaru Natori Shizue Natori Hiroyuki Sekikawa Tomoyuki Takahashi Kenji Ogino Kousuke Tsuchiya Hisaya Sato 《Polymer》2010,51(6):1501-3438
The effect of polymer chain structure on the optical and electrical properties are reported for poly(4-diphenylaminostyrene) (PDAS), which was prepared by the living anionic polymerization of 4-diphenylaminostyrene (DAS) with the benzyllithium (BzLi)/N,N,N′,N′-tetramethylethylenediamine (TMEDA) system. The optical properties of PDAS are strongly affected by the stereoregularity of the PDAS polymer chain; intramolecular excimer-forming fluorescence was observed from PDAS with a syndiotactic-rich configuration. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of PDAS were approximately −5.4 and −2.0 eV, respectively, regardless of the polymer chain structure. The hole and electron drift mobilities for PDAS were in the order of 10−4 to 10−5 (cm2/V s) and 10−5 (cm2/V s), respectively, with negative slopes. The distance of each triphenylamino (TPA) group in the polymer chain was a major factor influencing the drift mobility of PDAS. The current-voltage (I-V) characteristics of PDAS were controllable according to the polymer chain structure of PDAS. 相似文献
95.
Ohmori T Morita H Tanaka M Miyauchi K Kasai D Furukawa K Miyashita K Ogawa N Masai E Fukuda M 《Journal of Bioscience and Bioengineering》2011,111(4):437-442
Rhodococcus jostii RHA1 accumulates chlorobenzoates (CBA) during the degradation of polychlorinated biphenyls (PCBs). CBA degradation is considered one of the rate-limiting steps in the complete degradation of PCBs. To reduce the accumulation of CBAs, the upper pathway enzyme genes for PCB degradation of RHA1 were introduced into a CBA-degrading bacterium, Burkholderia sp. NK8. The resulting recombinant strain exhibited no biphenyl 2,3-dioxygenase (BphA) activity encoded by bphAaAbAcAd genes, which encode the large and small subunits of the terminal oxygenase component and the ferredoxin and reductase subunits responsible for electron transfer from NADH to the large subunit. The remaining enzyme genes involved in the transformation of biphenyl to benzoate, bphB2C1D1, which encode dehydrogenase, ring-cleavage dioxygenase and hydrolase, conferred activities to NK8. To obtain the BphA activity of RHA1 in NK8, sets of BphA genes were constructed by combining the bphAaAbAcAd genes of RHA1 and bphA3A4 of Pseudomonas pseudoalcaligenes KF707, encoding the ferredoxin and reductase subunits. Hybrid derivatives of BphA containing the KF707 bphA3 conferred BphA activity to NK8, and a derivative containing the RHA1 bphAaAb and KF707 bphA3A4 genes exhibited the highest BphA activity. A plasmid containing the RHA1 bphAaAb and KF707 bphA3A4 genes plus the RHA1 bphB2C1D1 genes was constructed and introduced into NK8. The resulting recombinant strain efficiently degraded 2-, 3- and 4-chlorobiphenyls with an apparent reduction in CBA accumulation in comparison to the recombinant mutant strain, which had an insertion in the cbeA gene to inactivate CBA dioxygenase. 相似文献
96.
Uematsu Y Ogimoto M Kabashima J Suzuki K Kaneko R Funayama K Haneishi N Yasuno T Ogino S 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2005,46(4):133-138
Migration from multi-layer laminated film pouches intended for retort foods was investigated through HPLC analysis with a fluorescence detector, and measurements of residue on evaporation, consumption of potassium permanganate and total organic carbon. HPLC analysis revealed that the levels of migrants in oil and the water which were heated in the pouches (121 degrees C, 30 min) were ten times of those in the corresponding official simulants under the official conditions; n-heptane (25 degrees C, 60 min), and water (95 degrees C, 30 min). Bisphenol A diglycidyl ether and related compounds were found in the oil and the water heated in the pouches, as well as in the simulants. These compounds were thought to have been present in the adhesive between the laminated films, and migrated through the food-contact film of the package. Consumption of potassium permanganate and residue on evaporation of the heated water were ten times of those of the water simulant, while the total organic carbon level of the heated water was several-hold greater than that of the water simulant. In addition, migrant levels per surface area of the pouch were one-fourth of the concentrations per content volume of the pouch. Since compliance with the legal limits is evaluated based on the concentration per surface area, real migration into foods would be underestimated by a factor of another four. 相似文献
97.
Atomic force microscopy (AFM) can dynamically detect the adhesion or affinity force between a sample surface and a cantilever. This feature is useful as a detection method using aptamers--single-strand DNA that recognizes its target with very high affinity. The present study proposes a novel DNA aptamer-based sensing system using AFM. In this study, thrombin was chosen as the target molecule, and a DNA aptamer-based AFM sensing system based on competition was developed. The affinity force between the gold chip and the cantilever decreased as the concentration of thrombin increased. Moreover, a low detection limit of 0.2 nM was achieved. Therefore, the AFM sensing system used would be appropriate for the measurement of various chemical compounds. 相似文献
98.
Yuya Tachibana Takuya Maeda Osamu Ito Yasukatsu Maeda Masao Kunioka 《International journal of molecular sciences》2009,10(8):3599-3615
We have developed a mulch sheet made by inflation molding of PLA, Ecoflex® and modified starch, which all have different biodegradabilities. A field test of use as an agricultural mulch sheet for mandarin oranges was carried out over two years. The mechanical properties of the mulch sheet were weakened with time during the field test, but the quality of the mandarin oranges increased, a result of the controlled degradation of the sheet. The most degradable modified starch degraded first, allowing control of the moisture on the soil. Accelerator mass spectroscopy was used for evaluation of the biomass carbon ratio. The biomass carbon ratio decreased by degradation of the biobased materials, PLA and modified starch in the mulch sheet. 相似文献
99.
Masao Kubo Takashi Matsubara Satoshi Shimizu Hiroshi Sato 《Artificial Life and Robotics》2010,15(2):207-211
In this article, a new localization approach for a team of robots that use the emergent properties of their formation is proposed.
Synchronized behavior sometimes generates spin-off effects that include geometric patterns. The question then arises as to
whether it is possible to use these patterns for something important for robots. In this article, Takayama’s control strategy,
which is a target enclosure formation, is discussed. A simple and useful expansion of Monte Carlo localization by the emergent
pattern is proposed. The proposed algorithms are confirmed through a series of computer simulations. 相似文献
100.
Itaru Natori Shizue Natori Anna Kanasashi Kosuke Tsuchiya Kenji Ogino 《Reactive and Functional Polymers》2013,73(1):200-206
The synthesis of tetraphenylporphyrin (H2TPP)-end-functionalized poly(p-phenylene) (H2TPP-PPP) as a leaf-green-colored soluble semiconducting polymer with a well-controlled and defined polymer chain structure was achieved for the first time. Chloromethyl-end-functionalized poly(1,3-cyclohexadiene) (CM-PCHD) was prepared by the living anionic polymerization of 1,3-cyclohexadiene and the post-polymerization reaction of poly(1,3-cyclohexadienyl)lithium and chloro(chloromethyl)dimethylsilane. H2TPP-end-functionalized PCHD (H2TPP-PCHD) was then prepared by the addition of 5-(4-hydroxyphenyl)-10,15,20-triphenylporphyrin to CM-PCHD. The dehydrogenation of H2TPP-PCHD with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone was performed under ultrasonic irradiation, and H2TPP-PPP was obtained as a target polymer in almost quantitative yield. The –Si(CH3)2–CH2–O– bond in H2TPP-PPP effectively inhibited the coordination of the H2TPP end-group onto the PPP moiety, and the aggregation of H2TPP-PPP with the accumulation of the H2TPP end-group was formed. H2TPP-PPP exhibited a leaf-green color and had a very broad absorption band overlapping the visible-light region, similar to chlorophyll a. 相似文献