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61.
The operation of an ideal heat integrated dlstillation columan (HIDiC) is addressed .Five Kinds of control configurations, i.e. single-loop control, multi-loop control, multivariable internal model control (IMC), modified multlvariable internal model control (MIMC) and nonlinear process model-based control (NPMC), are designed and applied to the process. Simulation results demonstrate that all of the above control confaguratloam ere valid for product quality control. NPMC control configuration is found to be the best one among all the alternatives. It can readily realize setpoint transitions and conduct effectively against external disturbance. MIMC control configuration ranks second in the row for its regulatory responses to feed composition disturbances with relatively extended setting time, Next comes from the multi-loop control configuration, which is moee or lees handicapped by its greater deviations and overshootings. IMC control configuration can not compete with the multi-loop control configuration because it is extremely sensitive to operating condition changes. Single-ioop control configuration is the worst one among all the mentioned control configurations. Its responses for the uncoutrolled end products are extremely sluggish. 相似文献
62.
Takamatsu K Takano A Yakushiji N Morohashi K Morishita K Matsuura N Makishima M Tai A Sasaki K Kakuta H 《ChemMedChem》2008,3(5):780-787
Retinoid X receptor (RXR) agonists (rexinoids) are attracting much attention for their use in treatment of cancers, including tamoxifen-resistant breast cancer and taxol-resistant lung cancer, and metabolic disease. However, known RXR agonists have a highly lipophilic character. In addition, no subtype-selective RXR agonists have been found. We previously reported an RXRalpha-preferential agonist 4-[N-methanesulfonyl-N-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-2-naphthyl)amino]benzoic acid (6 a). The RXR agonistic activity is much less than that of well-known RXR agonists. To develop potent, less-lipophilic, and subtype-selective RXR agonists, we created new RXR agonists possessing alkoxy and isopropyl groups as a lipophilic domain of the common structure of well-known RXR agonists. As a result, compounds possessing branched alkoxy groups, 6-[N-ethyl-N-(3-isopropoxy-4-isopropylphenyl)amino]nicotinic acid (NEt-3IP: 7 a) and 6-[N-ethyl-N-(3-isobutoxy-4-isopropylphenyl)amino]nicotinic acid (NEt-3IB: 7 c), showed RXR agonistic activity as potent as, or more potent than, the activities of representative RXR agonists. Moreover, NEt-3IP (7 a) was found to be the first RXRalpha/beta-selective (or RXRalpha/beta-dual) agonist. Being potent, less lipophilic, and having RXR subtype-selective activity, NEt-3IP (7 a) is expected to become a new drug candidate and to be a useful biological tool for clarifying each RXR subtype function. 相似文献
63.
64.
Ogawara K. Takamatsu J. Kimura H. Ikeuchi K. 《Industrial Electronics, IEEE Transactions on》2003,50(4):667-675
This paper describes a new approach on how to teach a robot everyday manipulation tasks under the "Learning from Observation" framework. In this approach, human demonstrations, which are made up of mutual interactions between a grasped object and an environmental object, are observed and a reusable manipulation task model is automatically generated. Most of the similar approaches so far assume that a demonstration can be well understood from a single demonstration. However, a single demonstration contains ambiguity, in that interactions which are essential to complete a task cannot be discerned without prior task dependent knowledge, which should be obtained from observation. To address these issues, a technique to integrate multiple observations of demonstrations is proposed. The demonstrations differ, but are virtually the same task. The shared interactions among all the demonstrations are considered to be essential and a task model is generated from their symbolic representations. Then, the relative trajectories corresponding to each essential interaction are generalized by calculating their mean and variance, and they are also stored in the task model, which is used to reproduce skilled behavior. This approach is examined by using a human-form robot, which successfully imitates human demonstrations of everyday tasks. 相似文献
65.
To investigate the RNA polymerase of rabies virus, we cloned a cDNA of the catalytic subunit (called L protein because of its large molecular size) of the HEP-Flury strain, an avirulent strain obtained by high frequencies of serial embryonated hen egg passages. Nucleotide sequencing showed that the cDNA encodes a long polypeptide of 2,127 amino acids (Mr. 242,938). A comparison of the deduced amino acid sequence with that of other strains (PV and SAD B19) indicated that the sequence was highly conserved, except for several amino acid substitutions which were accumulated in some limited regions. A fragment of the cDNA was used for expression in Escherichia coli (E. coli) to prepare the L antigen for raising the antibodies in rabbits. Immunoprecipitation studies with the rabbit antiserum showed that the polypeptides produced in the L cDNA-transfected COS-7 cells displayed almost the same electrophoretic mobility as that of authentic L protein. Immunofluorescence studies indicated that both L and P (another subunit of RNA polymerase) proteins displayed colocalized distribution with the nucleocapsid antigen (N) in the cytoplasmic inclusion bodies, where envelope proteins (G and M) were absent. On the other hand, expression of the L protein alone did not cause inclusion body-like granular distribution, suggesting that the inclusion body-like accumulation depends on certain interaction(s) with other viral gene products, probably with the ribonucleoproteins comprising the inclusion bodies. 相似文献
66.
Y Adachi I Takamatsu M Harada Y Uchihashi F Karasawa T Sato S Sugahara 《Canadian Metallurgical Quarterly》1998,47(12):1478-1481
This study evaluates the effects of low-doses i.v. fentanyl, buprenorphine and pentazocine on circulatory responses of endotracheal intubation in 70 scheduled surgical patients. Patients were allocated to 5 groups randomly and 2 (n = 11) or 4 (n = 13) micrograms.kg-1 of fentanyl, 0.5 mg.kg-1 of pentazocine (n = 13), 5 micrograms.kg-1 of buprenorphine (n = 10) and saline as a control (n = 23) were administered 5 minutes before the administration of thiopental, respectively. Then, patients were intubated with 0.1 mg.kg-1 of vecuronium. Blood pressure and heart rate were recorded. Only 4 micrograms.kg-1 of fentanyl diminished circulatory responses of systolic blood pressure on the stimuli of endotracheal intubation. 相似文献
67.
The best optimizing control procedure using an automatic optimizing controller, based on a simple pattern-search type, steepest ascent method is presented for a distillation column. The control system is composed of a conventional feedback loop by which the composition of overhead product is maintained constant, and an optimizing control unit which holds the partial derivatives of the objective function with respect to control variables to zero. The objective function used in this study is the profit rate obtained from the distillation process, and the two control variables; feed flow rate and energy supplied to the plant, are used. 相似文献
68.
Shuji Kiyohara Hideaki Takamatsu Taku Motoishi Katsumi Mori 《Journal of Materials Science: Materials in Electronics》2004,15(2):99-102
The fabrication of diamond nanopatterns by electron cyclotron resonance (ECR) oxygen plasma with a composite metal octylate mask was investigated using electron beam lithography technology. A high etching selectivity of 14 was obtained with Bi4Ti3O12 octylate film as a mask under the plasma-etching conditions of microwave power of 300 W and oxygen gas flow rate of 3 sccm. The metal naphthenates and metal octylates exhibited negative exposure characteristics. The sensitivity of metal naphthenates (1.2×10–3 C cm–2) was ten times lower than that of polymethyl methacrylate (PMMA) resist, while that of octylates (8.0×10–5 C cm–2) was in good agreement with that of PMMA resist (6.0×10–5 C cm–2). The resulting minimum chemical vapor deposited (CVD) diamond line-width of 100 nm with a height of approximately 1 m was fabricated with a Bi4Ti3O12 octylate mask. 相似文献
69.
Indium tin oxide (ITO) films were deposited on glass substrate at temperatures ranging from room temperature to 120 °C by the dc arc discharge ion plating technique. The electrical properties and crystallinity of ITO films were investigated. The resistivity of ITO films decreased with the increase of the substrate temperature in deposition, mostly due to increase in Hall mobility above 90 °C. The resistivity of ITO film obtained at temperature 120 °C was 1.33×10−4 Ω cm. The ITO films crystallized at the substrate temperature higher than 90 °C and the grain size estimated from the (2 2 2) peak in the direction parallel to the surface of the substrate became large with the increase of the substrate temperature. That the Hall mobility increased with the increase of the substrate temperature was speculated to be due to the increase of the grain size in the direction parallel to the surface. 相似文献
70.
Amachi S Kasahara M Hanada S Kamagata Y Shinoyama H Fujii T Muramatsu Y 《Environmental science & technology》2003,37(17):3885-3890
The roles of microorganisms in iodine volatilization from soils were studied. Soils were incubated with iodide ion (I-), and volatile organic iodine species were determined with a gas chromatograph. Iodine was emitted mainly as methyl iodide (CH3I), and CH3I emission was sometimes enhanced by the addition of glucose. Soils were then incubated with a radioactive iodine tracer (125I), and radioiodine emitted from soils was determined. The emission of iodine was enhanced in the presence of yeast extract but was inhibited by autoclaving of soils. The addition of streptomycin and tetracycline, antibiotics that inhibit bacterial growth, strongly inhibited iodine emission, while a fungal inhibitor cycloheximide caused little effect. Forty bacterial strains were randomly isolated from soils, and their capacities for volatilizing iodine were determined. Among these, 14 strains volatilized significant amounts of iodine when they were cultivated with iodide ion. Phylogenetic analysis based on 16S ribosomal DNA sequences showed thatthese bacteria are widely distributed through the bacterial domain. Our results suggest that iodine in soils is methylated and volatilized as CH3I by the action of soil bacteria and that iodine-volatilizing bacteria are ubiquitous in soil environments. The pathway of iodine volatilization by soil bacteria should be important for understanding the biogeochemical cycling of iodine as well as for the assessment of long-lived radioactive iodine (129I) in the environment. 相似文献