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研究二阶泛函微分方程x(t) p(t)x(t) q(t)x(t) ?(t,xt)=0的稳定性问题,利用Liapunov第二方法获得某些充分性判据。 相似文献
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利用C*-代数到B(H)中的等距*-表示,研究C*-代数中的Bohr不等式,得到了4个推广的Bohr不等式成立的一些充分必要条件.主要结论如下:设p,q∈R+,且满足1/p+1/q=1,则(V) A,B∈S(S为有单位元的C*-代数),| A-B | 2+|(1-p)A-B | 2≤p|A|2+q| B|2成立当且仅当p≤2;设α,β,u,u∈R,p,q∈R+,则|αA+βB| 2+|uA+vB| 2≤p|A|2+q | B | 2成立当且仅当p≥α2+u2,q≥β2+v2且(p-(α2+ u2))(q-(β2+v2))≥(αβ+uv)2;设a,b∈R+,c∈C,则VA,B∈S,a|A|2+b|B|2+cA*B+cB*A≥0成立当且仅当ab≥|c | 2;设α,β∈R,x,y是正数,则(V)A,B∈S,|αA+βB| 2≤x|A|2+y|B|2成立,当且仅当x≥α2,y≥β2且(x-α2)(y-β2)≥α2β2. 相似文献
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《现代家电》2003,(5):54-54
﹁!Jll刁I|月|.月!|门11|门J.|刁leeesjes.门||月|J|J|Jes|J.|门.Jesjljjjl|JIJ|IJ月es.|.|刁eses.1毛111!lles月.|I川|l当!es州l罐产品名称产品名称家用电风扇54彩色电视机微波炉抽油烟机燃气热水器厂l卜|l,厂眨1.|……编………11…l卜es.es.|l|esles.lles|...es|les.l|1..11苦!l胜.1||卜l||es||1164彩色电视机吸尘器投影电视机影碟机家用电脑家用电冰箱电热水器家用电冰拒电饭锅家用空调器双缸洗衣机电熨斗全自动洗衣机 综合占有率%,1 6.86 1 4.69 1 5.44 1 4.66,!4 .62}1 3.11}1 7.01 1 1 .47 9 .19 1 5.86{1 4.34一1 0.22「4 .79… 相似文献
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《纺织高校基础科学学报》2016,(2)
利用C*-代数到B(H)中的等距*-表示,研究C*-代数中的Bohr不等式,得到了4个推广的Bohr不等式成立的一些充分必要条件1.主要结论如下:设p,q∈R~+,且满足1/p+1/q=1,则A,B∈S(S为有单位元的C*-代数),|A-B|~2+|(1-p)A-B|~2≤p|A|~2+q|B|~2成立当且仅当p≤2;设α,β,u,v∈R,p,q∈R~+,则|αA+βB|~2+|uA+vB|~2≤p|A|~2+q|B|~2成立当且仅当p≥α~2+u~2,q≥β~2+v~2且(p-(α~2+u~2))(q-(β~2+v~2))≥(αβ+uv)~2;设a,b∈R~+,c∈C,则A,B∈S,a|A|~2+b|B|~2+cA*B+cB*A≥0成立当且仅当ab≥|c|2;设α,β∈R,x,y是正数,则A,B∈S,|αA+βB|~2≤x|A|~2+y|B|~2成立,当且仅当x≥α~2,y≥β~2且(x-α~2)(y-β)≥α~2β~2. 相似文献
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设C为实Hilbert空间H的非空闭凸子集,P:H→C为最近点投影映射,T:C→H为非扩张映象,且T满足弱内向条件,f:C→C为压缩映象.任意t∈(0,1),定义了2种隐式粘性迭代序列(xt),(yt)和2种显式粘性迭代序列{xn},{yn},证明了T有不动点当且仅当序列{xt},{yt},{xn},{yn}有界.且在适当条件下,迭代序列(隐或显)强收敛于T的一个不动点.所得结果在实Hilbert空间上推广与发展了有关文献的相应结果。 相似文献
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2011年,A|X Armani Exchange将迈进品牌20周年。为了纪念品牌20周年历程,Giorgio Armani将专门为A|X20周年设计一个特别系列并命名为A|XX,从2011年3月30日开始,各个A|X门店将会出售A|XX系列,每件为20周年精心设计的特别款都会附以极富代表性的全新标记-A|XX。 相似文献
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讨论了具有记忆项的非线性黏弹性方程的初边值问题utt+△2u+αu+r|u|ξu-∫t0g(t-τ)△2u (τ)dτ+β|ut|put=0.利用Galerkin方法和紧致性原理得到了整体解的存在性和渐近性. 相似文献
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《粮食与饲料工业》1984,(4)
续…”本额{职工}翌}竺17。0}一四||州||r叫|l|eswe|川Z0l||||||||141|叫||i|一…一1955|洲设洛{。业名称年份…而{癫诚开,。:6}世成泰火磨企业所在地哈尔城哈尔浓1115llwell4eees.|.116|l|1026!;、新第三}。{上海代宗翻、浦文}孤王禹卿股份无限公司厂粉16}长丰面冲J-陆维篇(怡下洋行买办)、偷钧甫、曹连生(均系商人)、股份无限公司泞春裕等n甘八U尸口﹄勺片艺‘上茂新面粉第二J一护宗故、价‘大{豁雷沁锡无盆新面粉第三厂无错荣戈导敬、生荣德股份无限公司lwewe创叫esl月恻|esl 91血 ﹃.山,生1916,湖南第一机4湖南长沙 }器面枷一!{1916!… 相似文献
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Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides. 相似文献
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John Gilbert Catherine Simoneau David Cote Achim Boenke 《Food Additives & Contaminants》2000,17(10):889-893
An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium. 相似文献
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Sophie Guillot Laurence Peytavi Sylvie Bureau Renaud Boulanger Jean-Paul Lepoutre Jean Crouzet Sabine Schorr-Galindo 《Food chemistry》2006
The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties. 相似文献
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Jesus Simal-Gandara Miguel Sarria-Vidal Arjen Koorevaar Rinus Rijk 《Food Additives & Contaminants》2000,17(8):703-711
The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials. 相似文献
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M. S. Garcí a-Falc n J. Simal-G ndara S. T. Carril-Gonz lez-Barros 《Food Additives & Contaminants》2000,17(12):957-964
A simple, rapid and inexpensive method has been developed for the determination of benzo[a 相似文献
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H. J. Van Den Top A. Boenke P. A. Burdaspal J. Bustos H. P. Van Egmond T. Legarda A. Mesego A. Mourino W. E. Paulsch C. Salgado 《Food Additives & Contaminants》2001,18(9):810-824
This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance. 相似文献
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《肉类研究》2014,(2)
<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the 相似文献
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《印刷工业》2014,(11):95-95
According to Printing and Printing Equipment Industries Association of China(PEIAC)'s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%. 相似文献
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《印刷工业》2014,(8):103-103
正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press 相似文献