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Multi-satellite observation integrated scheduling method oriented to emergency tasks and common tasks 被引量:23
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作者 Guohua Wu Manhao Ma +1 位作者 Jianghan Zhu Dishan Qiu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第5期723-733,共11页
Satellite observation scheduling plays a significant role in improving the efficiency of satellite observation systems.Although many scheduling algorithms have been proposed,emergency tasks,characterized as importance... Satellite observation scheduling plays a significant role in improving the efficiency of satellite observation systems.Although many scheduling algorithms have been proposed,emergency tasks,characterized as importance and urgency(e.g.,observation tasks orienting to the earthquake area and military conflict area),have not been taken into account yet.Therefore,it is crucial to investigate the satellite integrated scheduling methods,which focus on meeting the requirements of emergency tasks while maximizing the profit of common tasks.Firstly,a pretreatment approach is proposed,which eliminates conflicts among emergency tasks and allocates all tasks with a potential time-window to related orbits of satellites.Secondly,a mathematical model and an acyclic directed graph model are constructed.Thirdly,a hybrid ant colony optimization method mixed with iteration local search(ACO-ILS) is established to solve the problem.Moreover,to guarantee all solutions satisfying the emergency task requirement constraints,a constraint repair method is presented.Extensive experimental simulations show that the proposed integrated scheduling method is superior to two-phased scheduling methods,the performance of ACO-ILS is greatly improved in both evolution speed and solution quality by iteration local search,and ACO-ILS outperforms both genetic algorithm and simulated annealing algorithm. 展开更多
关键词 satellite scheduling emergency task ant colony optimization(ACO) iteration local search(ils) acyclic directed graph model
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An efficient fluorination of β-ketosulfones promoted by a room-temperature ionic liquid at ambient conditions under ultrasound irradiation using Selectfluor^(TM) F-TEDA-BF_4 被引量:3
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作者 Mohammad Reza Poor Heravi 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第12期1399-1402,共4页
The fluorination reaction involving a β-ketosulfones by Selectfluor^TM was efficiently promoted by the ionic liquid, [Hbim]BF4 (IL) as a reaction medium with methanol as co-solvent at room temperature under ultraso... The fluorination reaction involving a β-ketosulfones by Selectfluor^TM was efficiently promoted by the ionic liquid, [Hbim]BF4 (IL) as a reaction medium with methanol as co-solvent at room temperature under ultrasonic irradiation to afford the corresponding mono and difluoro-β-ketosulfones in excellent yields. The advantages of this method include among others the use of a recyclable, non-volatile ionic liquid, which promotes this protocol under room temperature without the requirement of any added catalyst under ultrasonic irradiation. 展开更多
关键词 FLUORINATION Ultrasound irradiation β-Ketosulfones Selectfluor^TM Ionic liquids(ils)
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Detection of Drought-Related Loci in Rice at Reproductive Stage Using Selected Introgressed Lines 被引量:3
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作者 CHEN Man-yuan Ali j +8 位作者 FU Bin-ying XU Jian-long ZHAO Ming-fu JIANG Yun-zhu ZHU Ling-hua SHI Ying-yao YAO Da-nian GAO Yong-ming LI Zhi-kang 《Agricultural Sciences in China》 CAS CSCD 2011年第1期1-8,共8页
The present study was carried out to illustrate high-efficient detection of quantitative trait loci (QTLs) with selected introgression lines (ILs) and the existence of 'hidden genes' conferring drought tolerance... The present study was carried out to illustrate high-efficient detection of quantitative trait loci (QTLs) with selected introgression lines (ILs) and the existence of 'hidden genes' conferring drought tolerance (DT). 52 selected DT ILs, derived from BC2Fz population developed by crossing and backcrossing the susceptible recurrent parent (RP) IR64 with the susceptible donor Khazar were planted under irrigation and drought condition. Four important agronomic traits, e.g., grain yield (GY), heading date (HD), panicle numbers per plant (PN), and plant height (PH) were evaluated and 83 SSR polymorphic molecular markers were used for genotypic analysis. Chi-square test based on genetic hitch-hiking and one-way analysis of variances (ANOVA) were used to detect drought-related loci. Nine and 36 loci were detected by chi-square test and one-way ANOVA, respectively. Five common loci were observed by comparing the results of the two methods, among which two QTLs linked with RM7, and RM241 were detected under irrigation condition, both of the favorable alleles were from RP and explained 13% phenotypic variation (PV) for GY and 28% PV for PH, respectively. The other three QTLs linked with RM 163, RM 18, and RM270 were detected under drought condition, the favorable alleles were all from the donor and explained 10, 24, and 19% PV for HD, PH, and PH, respectively. Five common loci were observed by comparing the results of chi-square test and one-way ANOVA including two QTLs (one for GY and one for PH) under irrigation condition and three QTLs (one for HD and two for PH) under drought condition. By combining phenotypic and genotypic analysis, drought escape could be inferred as the main mechanism for drought tolerance in the present study. The results in present study suggested that the selected ILs population analyzed by chi-square test and one-way ANOVA was quite effective for DT QTL detection with low inputs and could also produce useful materials for breeding with wide genetic diversity for drought tolerance. 展开更多
关键词 RICE drought tolerance introgression lines (ils) quantitative trait loci (QTL) hidden diversity
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Synthesis and Characterization of Poly [2,2-( m-phenylene) -5,5-bibenzimidazole] in 1-butyl-3-methylimidazolium Chloride
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作者 白雪君 王彪 +3 位作者 唐艳芳 文志伟 江建明 王华平 《Journal of Donghua University(English Edition)》 EI CAS 2013年第3期239-243,共5页
Poly[ 2, 2-(m.phenylene) -5, 5-bibenzimidazole] (mPBI) were synthesized by mixing 3, 3', 4, 4'-tetraaminobiphenyl and isophthallc acid in 1 -butyl-3 -methyUmidazolinm chloride ( E BMIM] CI). Intrinsic viscosit... Poly[ 2, 2-(m.phenylene) -5, 5-bibenzimidazole] (mPBI) were synthesized by mixing 3, 3', 4, 4'-tetraaminobiphenyl and isophthallc acid in 1 -butyl-3 -methyUmidazolinm chloride ( E BMIM] CI). Intrinsic viscosity of mPBI polymers was 0.67 dL/g which was measured in 96% sulfuric acid. The polymer was characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance ( 1H-NMR ), and thermogravimetric analysis (TGA). The effects of polymerization conditions on the intrinsic viscosity of mPBI were investigated. It showed that the molecular weight of polymer mainly depended on pre-reaction time and reaction temperature. Comparison of structure and properties of mPBI synthesized in ionic liquids(ILs) and polyphosphoric acid was also reported. It indicates that the ionic liquids are a kind of good solvents in synthesis process of m_PBI and ionic liquids mainly affect molecular weight of mPBL 展开更多
关键词 polybenzimidazole PBI 1-butyl-3-methylimidazolium chloride( [ BMIM] C1 ionic liquids(ils) synthesis
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沉默的力量——感悟伊尔泽·艾辛格的诗集《送出的建议》
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作者 姜丽 《同济大学学报(社会科学版)》 2005年第6期26-31,共6页
伊尔泽·艾辛格1921年11月1日生于奥地利维也纳,母亲是犹太人。二战期间伊尔泽一家好几个人被送进集中营,无一人生还。这段人生经历使她走向写作,并把写作定义为沉默。这沉默使她的作品,尤其是诗歌少有人读,使评论家们找不到可以用... 伊尔泽·艾辛格1921年11月1日生于奥地利维也纳,母亲是犹太人。二战期间伊尔泽一家好几个人被送进集中营,无一人生还。这段人生经历使她走向写作,并把写作定义为沉默。这沉默使她的作品,尤其是诗歌少有人读,使评论家们找不到可以用来分析它们的理论,只能不断地引用她的话、她的作品来解释她的作品。然而伊尔泽·艾辛格的作品的魅力就在于虽然难懂,却牢牢地吸引着你,所以从1952到2002年她已在19个大小奖项中获奖。可以说,这就是艾辛格的沉默的力量。在她的诗集《送出的建议》中沉默无处不在,让你惊奇,让你无法释怀。 展开更多
关键词 沉默 写作 惊奇
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Separation and recovery of critical metal ions using ionic liquids 被引量:1
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作者 Terence Makanyire Sergio Sanchez-Segado Animesh Jha 《Advances in Manufacturing》 SCIE CAS CSCD 2016年第1期33-46,共14页
Separation and purification of critical metal ions such as rare-earth elements (REEs), scandium and niobium from their minerals is difficult and often deter- mines if extraction is economically and environmentally f... Separation and purification of critical metal ions such as rare-earth elements (REEs), scandium and niobium from their minerals is difficult and often deter- mines if extraction is economically and environmentally feasible. Solvent extraction is a commonly used metal-ion separation process, usually favored because of its sim- plicity, speed and wide scope, which is why it is often employed for separating trace metals from their minerals. However, the types of solvents widely used for the recovery of metal ions have adverse environmental impact. Alternatives to solvent extraction have been explored and advances in separation technologies have shown commer- cial establishment of liquid membranes as an alternative to conventional solvent extraction for the recovery of metals and other valuable materials. Liquid membrane transport incorporates solvent extraction and membrane separation in one continuously operating system. Both methods con- ventionally use solvents that are harmful to the environ- ment, however, the introduction of ionic liquids (ILs) over the last decade is set to minimize the environmental impact of both solvent extraction and liquid membrane separation processes. ILs are a family of organic molten salts with low or negligible vapour pressure which may be formed below 100 ~C. Such liquids are also highly thermally stable and less toxic. Their ionic structure makes them thermody- namically favorable solvents for the extraction of metallic ions. The main aim of this article is to review the current achievements in the separation of REE, scandium, niobium and vanadium from their minerals, using ILs in eithersolvent extraction or liquid membrane processes. The mechanism of separation using ILs is discussed and the engineering constraints to their application are identified. 展开更多
关键词 Critical metals Ionic liquids (ils) -Niobium Tantalum Rare-earth elements (REEs)Vanadium SCANDIUM
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