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21.
Tsuyoshi Takahashi Masahito Kitou Michio Asai Mitsuyasu Kido Tomio Chiba Junzou Kawakami Yoshiaki Matsui 《Electrical Engineering in Japan》1994,114(2):18-33
Power system control equipment needs higher sensitivity and operational reliability. Advanced voltage control equipment is needed for reducing the frequency of tap changes and improving the characteristics (the relationship between the actual voltage and reference voltage) of the voltage to meet today's power system requirements. However, these objectives are in a trade-off relationship. Studies of voltage control derived from a knowledge base suitable for electric power systems can satisfy these objectives using fuzzy inference. Compared with corresponding conventional equipment, the new equipment improved the deviation of 30 min average voltage of 30 percent. This paper describes the design concept of new voltage control equipment using fuzzy inference. In addition, field test results are described along with rules of fuzzy inference, membership functions, and the deviation of 30 min average voltage through detailed simulation. 相似文献
22.
23.
Blends of polyamide and high‐density polyethylene show adequate properties for a large range of applications: they are used for the production of filaments, containers, and molding resins. The effect of the addition of 2 wt % of a compatibilizer, maleic anhydride grafted polyethylene, to the blend was studied and compared to the use of postconsumer polyethylene. The samples were extruded with single‐ and twin‐screw extruders with 25, 50, or 75 wt % f polyethylene, and the test specimens, molded by injection, were characterized by stress–strain tests, thermal properties, and morphologies. Processing the blends with postconsumer polyethylene in both extruders improved the mechanical properties in comparison to the blends processed with high‐density polyethylene and the compatibilizer. The morphologies of these blends showed that there was a decrease in the domain size of the disperse phase with the use of the compatibilizer or postconsumer polyethylene. The results indicate that for this blend, postconsumer polyethylene substituted, with advantages, for the necessity of a compatibilizer and the use of the high‐density polyethylene. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008. 相似文献
24.
The in situ measurement of dynamic changes in viscosity induced by illumination has been performed on a range of photosensitive urethane dimethacrylates (UDMA) evaluating the response at three different illuminations intensities (1, 2, and 5 W cm?2) and at three different diluent concentrations (15, 30, and 50%), using 1,6‐hexanediol dimethacrylate (HDDMA). The initial viscosity value ranged between 1 and 10 Pa s for the mixtures with final viscosities approaching 1 × 107 Pa s after illumination. The initial rise in viscosity was analyzed using an exponential model with an exponent ranging from 1.0 to 2.5 with time under exposure. Higher conversion rates were observed with both higher intensity and lower HDDMA content. The analytical approach taken here could aid in developing more sophisticated models that consider simultaneous flow and cure advancement in other thermosets. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
25.
Separations through reactions can provide reliable and economically viable alternatives to established methods of separation,
particularly for close boiling substances. New strategies in ‘Dissociation Extraction’ and ‘Dissociation Extractive Crystallization’
for separation of close boiling acidic/basic mixtures have been highlighted. Separations with aqueous solutions of hydrotrope
and aqueous micellar solutions have been brought out. Separations by membranes with facilitated transport is potentially attractive.
This paper is dedicated to Dr L K Doraiswamy on his sixtieth birthday. 相似文献
26.
D.M. LEWIS 《International journal of cosmetic science》1996,18(3):123-135
The strength and nature of dye–fibre interactions vary according to fibre type and dye type. In the case of acid dyes for polyamide fibres, cationic dyes for acrylic fibres, disperse dyes for hydrophobic fibres, and direct dyes for cellulosic fibres, these interactions may be classified as non-covalent, a classification which includes van der Waals (VDW), electrostatic, induction, solvophobic and charge-transfer interactions.
Reactive dyes are a notable exception to the above, since the interaction which is responsible for their excellent wet fastness is the dye–fibre covalent bond, however, these dyes are increasingly viewed as environmentally unfriendly due to high salt usage and residual unfixed colour. This situation may be improved by either incorporating amine sites in the cellulose or by reversing the system to incorporate reactive residues in the fibre and nucleophilic sites in the dye.
Nonionic disperse dyes are valuable for hydrophobic fibres such as polyester but have made little impact on hydrophilic fibres such as silk, wool and cotton. Experiments to develop simple treatments to render the latter fibres disperse dyeable are described and the combined role of solvophobic and – interactions discussed. 相似文献
Reactive dyes are a notable exception to the above, since the interaction which is responsible for their excellent wet fastness is the dye–fibre covalent bond, however, these dyes are increasingly viewed as environmentally unfriendly due to high salt usage and residual unfixed colour. This situation may be improved by either incorporating amine sites in the cellulose or by reversing the system to incorporate reactive residues in the fibre and nucleophilic sites in the dye.
Nonionic disperse dyes are valuable for hydrophobic fibres such as polyester but have made little impact on hydrophilic fibres such as silk, wool and cotton. Experiments to develop simple treatments to render the latter fibres disperse dyeable are described and the combined role of solvophobic and – interactions discussed. 相似文献
27.
Amirah Mohammad-Sidik Jian Sun Ryoung Shin Zhizhong Song Youzheng Ning Elsa Matthus Katie A. Wilkins Julia M. Davies 《International journal of molecular sciences》2021,22(2)
Extracellular ATP (eATP) has long been established in animals as an important signalling molecule but this is less understood in plants. The identification of Arabidopsis thaliana DORN1 (Does Not Respond to Nucleotides) as the first plant eATP receptor has shown that it is fundamental to the elevation of cytosolic free Ca2+ ([Ca2+]cyt) as a possible second messenger. eATP causes other downstream responses such as increase in reactive oxygen species (ROS) and nitric oxide, plus changes in gene expression. The plasma membrane Ca2+ influx channels involved in eATP-induced [Ca2+]cyt increase remain unknown at the genetic level. Arabidopsis thaliana Annexin 1 has been found to mediate ROS-activated Ca2+ influx in root epidermis, consistent with its operating as a transport pathway. In this study, the loss of function Annexin 1 mutant was found to have impaired [Ca2+]cyt elevation in roots in response to eATP or eADP. Additionally, this annexin was implicated in modulating eATP-induced intracellular ROS accumulation in roots as well as expression of eATP-responsive genes. 相似文献
28.
Ssu-Yu Chen Yung-Lung Chang Shu-Ting Liu Gunng-Shinng Chen Shiao-Pieng Lee Shih-Ming Huang 《International journal of molecular sciences》2021,22(7)
Disulfiram (DSF), an irreversible aldehyde dehydrogenase inhibitor, is being used in anticancer therapy, as its effects in humans are known and less adverse than conventional chemotherapy. We explored the potential mechanism behind the cytotoxicity of DSF-Cu+/Cu2+ complexes in oral epidermoid carcinoma meng-1 (OECM-1) and human gingival epithelial Smulow-Glickman (SG) cells. Exposure to CuCl2 or CuCl slightly but concentration-dependently decreased cell viability, while DSF-Cu+/Cu2+ induced cell death in OECM-1 cells, but not SG cells. DSF-Cu+/Cu2+ also increased the subG1 population and decreased the G1, S, and G2/M populations in OECM-1 cells, but not SG cells, and suppressed cell proliferation in both OECM-1 and SG cells. ALDH enzyme activity was inhibited by CuCl and DSF-Cu+/Cu2+ in SG cells, but not OECM-1 cells. ROS levels and cellular senescence were increased in DSF-Cu+/Cu2+-treated OECM-1 cells, whereas they were suppressed in SG cells. DSF-Cu+/Cu2+ induced mitochondrial fission in OECM-1 cells and reduced mitochondrial membrane potential. CuCl2 increased but DSF- Cu2+ impaired oxygen consumption rates and extracellular acidification rates in OECM-1 cells. CuCl2 stabilized HIF-1α expression under normoxia in OECM-1 cells, and complex with DSF enhanced that effect. Levels of c-Myc protein and its phosphorylation at Tyr58 and Ser62 were increased, while levels of the N-terminal truncated form (Myc-nick) were decreased in DSF-Cu+/Cu2-treated OECM-1 cells. These effects were all suppressed by pretreatment with the ROS scavenger NAC. Overexpression of c-Myc failed to induce HIF-1α expression. These findings provide novel insight into the potential application of DSF-CuCl2 complex as a repurposed agent for OSCC cancer therapy. 相似文献
29.
Luisa Siculella Laura Giannotti Benedetta Di Chiara Stanca Matteo Calcagnile Alessio Rochira Eleonora Stanca Pietro Alifano Fabrizio Damiano 《International journal of molecular sciences》2021,22(8)
Reactive intermediate deaminase (Rid) proteins are enzymes conserved in all domains of life. UK114, a mammalian member of RidA subfamily, has been firstly identified as a component of liver perchloric acid-soluble proteins (L-PSP). Although still poorly defined, several functions have been attributed to the mammalian protein UK114/RIDA, including the reactive intermediate deamination activity. The expression of UK114/RIDA has been observed in some tumors, arousing interest in this protein as an evaluable tumor marker. However, other studies reported a negative correlation between UK114/RIDA expression, tumor differentiation degree and cell proliferation. This work addressed the question of UK114/RIDA expression in human non-tumor HEK293 cell lines and in some human tumor cell lines. Here we reported that human RIDA (hRIDA) was expressed in all the analyzed cell line and subjected to lysine (K-)succinylation. In HEK293, hRIDA K-succinylation was negatively correlated to the cell proliferation rate and was under the control of SIRT5. Moreover, K-succinylation clearly altered hRIDA quantification by immunoblotting, explaining, at least in part, some discrepancies about RIDA expression reported in previous studies. We found that hRIDA was able to deaminate reactive enamine-imine intermediates and that K-succinylation drastically reduced deaminase activity. As predicted by in silico analysis, the observed reduction of deaminase activity has been related to the drastic alterations of hRIDA structure inferred by K-succinylation. The role of hRIDA and the importance of its K-succinylation in cell metabolism, especially in cancer biology, have been discussed. 相似文献
30.
Kavitej Samra Mathun Kuganesan William Smith Anna Kleyman Robert Tidswell Nishkantha Arulkumaran Mervyn Singer Alex Dyson 《International journal of molecular sciences》2021,22(6)
Metabolically active gasotransmitters (nitric oxide, carbon monoxide and hydrogen sulfide) are important signalling molecules that show therapeutic utility in oxidative pathologies. The reduced form of selenium, hydrogen selenide (HSe−/H2Se), shares some characteristics with these molecules. The simple selenide salt, sodium hydroselenide (NaHSe) showed significant metabolic activity, dose-dependently decreasing ex vivo O2 consumption (rat soleus muscle, liver) and transiently inhibiting mitochondrial cytochrome C oxidase (liver, heart). Pharmacological manipulation of selenoprotein expression in HepG2 human hepatocytes revealed that the oxidation status of selenium impacts on protein expression; reduced selenide (NaHSe) increased, whereas (oxidized) sodium selenite decreased the abundance of two ubiquitous selenoproteins. An inhibitor of endogenous sulfide production (DL-propargylglycine; PAG) also reduced selenoprotein expression; this was reversed by exogenous NaHSe, but not sodium hydrosulfide (NaHS). NaHSe also conferred cytoprotection against an oxidative challenge (H2O2), and this was associated with an increase in mitochondrial membrane potential. Anesthetized Wistar rats receiving intravenous NaHSe exhibited significant bradycardia, metabolic acidosis and hyperlactataemia. In summary, NaHSe modulates metabolism by inhibition of cytochrome C oxidase. Modification of selenoprotein expression revealed the importance of oxidation status of selenium therapies, with implications for current clinical practice. The utility of NaHSe as a research tool and putative therapeutic is discussed. 相似文献