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1.
Two types of molecular and polymer devices employing (2-(4′-biphenyl)-5-(4““““““““-tert-butylphenyl)-1,3,4-oxadiazole) (PBD)and poly(N-vinylcarbazole) (PVK) as electron transport and hole transport materials, respectively, have been fabricated. The structures of these two devices are ITO/PVK( 70 nm)/PBD(60 nm)/A1 and ITO/PVK: PBD (1:1 by mass, 70 nm)/A1. The formation of exciplex is evident by comparing the electroluminescence (EL) of a bi-layer device and the photoluminescence (PL) of a PVK and PBD mixed film.The maximum emission energy of exciplex evaluated is consistent with the peak emission of EL. Blue emissions from both devices are obtained. The type of exicplex is interpreted based on the energy level diagram of the bi-layer device. 相似文献
2.
《课堂内外(高中版)》2007,(Z1)
一、单项选择题(正规试题含选择题 70 道, 每道 1 分。本套试题共有 24 道。) 1. Which of the seven ancient wonders still exists? A. The Temple of Artemis at Ephesus. B. The Great Pyramid of Egypt. C. The Lighthouse of Alexandria. D. The Statue of Zeus at Olymp 相似文献
3.
李士芗 《现代远程教育研究》2000,(3)
综合练习 A1 完形填空(10分)Men first measured time (1) using a stick in the ground.The length of the (2) shadow would (3) what time of day itwas.(4),the Egyptians used a pillar,(5) as a gnomon,andthen developed a simple sundial,(6) consisted of a stone with apointer on it.The stone was placed in an east-west direction,and the shadow of the pointer showed the time.About 300 BC,a Babylonian (7) Berosus invented a semi-circular sundial,(8) he marked twelve hours.The Babyloni-am,like the Egyptians,divided daylight (9) twelve parts andnight into twelve.This meant that an hour would have differ-ent lengths (10) different times of the year.A daytime hourmight be longer or shorter than a nighttime one.These hoursare known as 'temporary hours'.(1)A.with B.byC.through D.in 相似文献
4.
任明俊 《中学数学教学参考》2005,(3):63-63
1.1 Some definitions (1)Outcome A result of an experiment is called an outcome. (2)Sample space The set of possible outcomes of an experiment is the sample space for the experiment. 相似文献
5.
任明俊 《中学数学教学参考》2005,(3)
1 Probability1.1 Some definitions (1)Outcome A result of an experiment is called an outcome. (2)Sample space The set of possible outcomes of an experiment is the sample space for the experiment. (3) Fair experiment If a sample space has n possi- 相似文献
6.
Ⅲ.Select an appropriate verb in brackets.(10%)1.Where(is,are)that five pounds I lent you?2.A series of pre-recorded tapes(has been,have been)prepared forlanguage laboratory.3.The majority of criminals(is,are)young men.4.This kind of apples(is,are)highly priced.5.The sum and substance of this argument(is,are)war and peace. 相似文献
7.
A.Each of the statements below is followed byfour alternative answers.Choose the one thatwould best complete the statement and put theletter in the brackets.(C)1.Which of the following two stories are tak-en from Irving's The Sketch Book of Geoffrey Cray-on,Gent..A.A History of New York and Tales of a TravelerB.Bracebridge Hall and Rip Van WinkleC.Rip Van Winkle and The Legend of Sleepy HollowD.The Legend of Sleepy Hollow and Tales of a 相似文献
8.
In this paper,we give all-sided pastic analysis of the rectangular slab with three edges simply-supported and other free.Here we discuss the following four cases:(1)The uniformly distributedload over the area a slab.(2).A concentrated load act at midpoint of free edges slab.(3)A concen-trated load act at the center a slab.(4)The line load act along free edge of slab. 相似文献
9.
A differential cross-coupled regulated cascode(RGC)transimpedance amplifier(TIA)is proposed. The theory of multi-stage common-source(CS) configuration as an auxiliary amplifier to enhance the bandwidth and output impedance of RGC topology is analyzed. Additionally, negative Miller capacitance and shunt active inductor compensation are exploited to further expand the bandwidth. The proposed RGC TIA is simulated based on UMC 0.18 μm standard CMOS process. The simulation results demonstrate that the proposed TIA has a high transimpedance of 60.5 d B?, and a-3 d B bandwidth of 5.4 GHz is achieved for 0.5 p F input capacitance. The average equivalent input noise current spectral density is about 20 p A/Hz~(1/2) in the interested frequency, and the TIA consumes 20 m W DC power under 1.8 V supply voltage. The voltage swing is 460 m V pp, and the saturation input current is 500 μA. 相似文献
10.
Xue Wang Liang-fei Zhan Qian-gang Pan Zhi-jun Liu Hong Liu Yong-shun Tao 《浙江大学学报(A卷英文版)》2010,11(10):756-760
A 9% Cr ferritic steel weld metal containing 1% Co, partially substituted for nickel, was prepared by submerged arc welding (SAW) processing. The microstructure and creep properties of the weld metal were investigated. The microstructure exhibited a fully tempered martensitic structure free of δ-ferrite. The creep properties of the obtained weld metal were inferior to those of the P92 base metal at 600 and 650 °C. The values of A and n for weld metal in the Norton power law constitution at 650 °C are 1.1×10?21 and 8.1, respectively. 相似文献
11.
A novel polycarbonate urethane was synthesized by the two-stage solution process of diisocyanates with polycarbonate diols(PCDL),in which PCDL,1,4-butanediol(BD) and mixture of 4,4'-methylenediphenyl diisocy-anate and hexamethylene diisocyanate(HDI) were soft segment,chain extender and rigid segment,respectively.The structures were characterized by using FTIR and 1H-NMR.The thermoanalysis and mechanical properties of products were measured by means of DSC,TG and other systems.The result shows that an import... 相似文献
12.
1.What well(井)don't you sink?2.What kind of belt(带子)you can’t fasten round yOtit waist?3.What kind of stockings(长 统袜)you don’t wear?4.What'S the’way(路)on which you can't walk?5.What cock(公鸡)won’t crov~’?答案:1.An inkwell.(墨水池)2.The cotton belt.(一种棉地带)3.A Blue-stocking(才女)4.The milky way.(银河)5.A weather-cock.(风标)双关语问答@胡芸芳… 相似文献
13.
Synthesis and Characterization of Novel Copolymers Based on 3 （S）-Methyl-Morpholine-2,5-Dione 总被引：1，自引：1，他引：0
A series of novel copolymers were successfully synthesized by ring-opening polymerization(ROP) of 3(S)-methyl-morpholine-2,5-dione(MMD) and 5-methyl-5-benzyloxycarbonyl-1,3-dioxan-2-one(MBC) using stannous octoate as catalyst.The copolymers were characterized by means of 1 H-NMR and FT-IR spectroscopy.Gel permeation chromatography(GPC) test shows that the average-number relative molecular mass and average-weight relative molecular mass slightly increase with the increase of MBC content in feed.The results of differential scanning calorimetry(DSC) demonstrate that the glass transition temperature of copolymers increases with the increase of MBC content in copolymers.The copolymers of MMD and MBC are amorphous copolymers,as indicated by DSC results,while the homopolymer of MMD is semicrystalline. 相似文献
14.
Wei HONG Kai WANG Yi-ping ZHANG Jun-yan KOU Dan HONG Dan SU Wei-min MAO Xin-min YU Fa-jun XIE Xiao-jian WANG 《Journal of Zhejiang University. Science. B》2013,14(3):207-215
Objective:The aim of this study was to evaluate the association between the methylenetetrahydrofolate reductase(MTHFR) C677T excision repair cross-complementation group 1(ERCC1) genetic polymorphisms and the clinical efficacy of gemcitabine-based chemotherapy in advanced non-small cell lung cancer(NSCLC).Methods:A total of 135 chemonaive patients with unresectable advanced NSCLC were treated with gemcitabine/platinum regimens.The polymorphisms of MTHFR C677T,ERCC1 C8092A,and ERCC1 C118T were genotyped using the TaqMan methods.Results:The overall response rate was 28.9%.Patients with MTHFR CC genotype had a higher rate of objective response than patients with variant genotype(TT or CT)(41.2% versus 19.1%,P=0.01).Median time to progression(TTP) of patients with MTHFR CC genotype was longer than that of patients with variant genotype(7.6 months versus 5.0 months,P=0.003).No significant associations were obtained between ERCC1 C118T and C8092A polymorphisms and both response and survival.Conclusions:Our data suggest the value of MTHFR C677T polymorphism as a possible predictive marker of response and TTP in advanced NSCLC patients treated with gemcitabine/platinum. 相似文献
15.
Li FZ Jin SH Hu GC Fu YP Si HM Jiang DA Sun ZX 《Journal of Zhejiang University. Science. B》2005,6(8):803-811
A rice pse(t) (premature senescence, tentatively) mutant line, was isolated from 4500 independent T-DNA inserted transgenic lines. The symptoms of premature senescence appeared more severely than those of the control plants (Zhonghua 11,japonica) at the last development stage. To characterize the mutant and provide basic information on the candidate genes by mapping to a physical region of 220-kb, experiments were carried out in two phytotrons under controlled temperature of 24 ℃ and28 ℃, respectively. The content of chlorophyll, soluble protein and MDA (malondialdehyde), net photosynthesis, the antioxidant enzyme activities of SOD (superoxide dismuase) (EC 1.15.1.1) and POD (peroxidase) (EC 1.11.1.7) and the peptidase activities of leaves were measured from top to bottom according to the leaf positions at the flowering stage. Compared with the control plant,the mutant showed the following characteristics: (1) Higher net photosynthesis rate (Pn) appeared in the 1 st and 2nd leaves, contents of chlorophyll and soluble protein were also higher in the 1 st leaf; (2) The activities of SOD, POD and peptidase were higher according to the leaf position from top to bottom; (3) The symptom of premature senescence was accelerated in the mutant at 28℃treatment. The MDA content and the SOD and POD activities between the 24 ℃ and 28 ℃ treatment mutants were not significantly different. Content of chlorophyll and soluble protein of leaves mutant decreased rapidly at 28 ℃ treatment. The results show that pse(t) is sensitive to high temperature. The probable function of PSE(T) is discussed. 相似文献
16.
A route for the synthesis of nefazodone is reported. Nefazodone was obtained with an overall yield of 37. 2% from phenol. The key steps involve the improved synthesis of 5-ethyl-4-(2-phenoxyethyl)-1, 2, 4-triazol-3(2H)-one, a key intermediate in the synthesis of nefazodone. The phenol was etherified with 1, 2-dichloroethane (75%), followed by iodination-amination with Nal and CH_3OH-NH_3(85.7%), acylation with ethyl chloroformate (95.7%) and cyclization with propionyl hy-drazine (83.6%). 相似文献
17.
A Beijing, Nov. 16 (Xinhuanet)-China's Ministry of Health on Wednesday confirmed(确认) two human cases and one suspected case of H5N1 bird flu. The two confirmed cases involve a nine-year-old boy in Xiangtan County of Hunan Province, central China, and a 24-year-old woman farmer in Zongyang County of Anhui Province in the east. The boy surnamed He had fever and showed pneumonia-like symptoms(肺炎症状) on Oct 10. There was an outbreak of H5N1 bird flu occurred in his village. Lab tests on the boy's blood serum (血清) samples 相似文献
18.
Guo-dong HAO Yi-wu ZHENG Birgitte GJESING Xing-ai KONG Jing-yuan WANG Zhi-jing SONG Xu-xin LAI Nan-shan ZHONG Michael D.SPANGFORT 《Journal of Zhejiang University. Science. B》2013,14(3):240-246
Objective:Weed pollens are common sources of allergens worldwide.The prevalence of weed pollen sensitization is not yet fully known in China.The purpose of this study was to investigate the prevalence of sensitization to weed allergens from Artemisia,Ambrosia,and Humulus in northern China.Methods:A total of 1144 subjects(aged from 5 to 68 years) visiting our clinic from June to October 2011 underwent intradermal testing using a panel of 25 allergen sources.Subjects with positive skin responses to any pollen were further tested for their serum concentrations of IgE antibodies against Artemisia vulgaris,Ambrosia artemisiifolia,and Humulus scandens,and against the purified allergens,Art v 1 and Amb a 1.Results:Of 1144 subjects,170 had positive intradermal reactions to pollen and 144 donated serum for IgE testing.The prevalence of positive intradermal responses to pollens of Artemisia sieversiana,Artemisia annua,A.artemisiifolia,and H.scandens was 11.0%,10.2%,3.7%,and 6.6%,respectively.Among the intradermal positive subjects,the prevalence of specific IgE antigens to A.vulgaris was 58.3%,to A.artemisiifolia 14.7%,and to H.scandens 41.0%.The prevalence of specific IgE antigens to the allergen Art v 1 was 46.9%,and to Amb a 1 was 11.2%.The correlation between the presence of IgE antibodies specific to A.vulgaris and to the Art v 1 antigen was very high.Subjects with A.artemisiifolia specific IgE also had A.vulgaris specific IgE,but with relatively high levels of A.vulgaris IgE antibodies.There were no correlations between the presence of IgE antibodies to H.scandens and A.vulgaris or to H.scandens and A.artemisiifolia.Conclusions:The intradermal prevalence of weed pollen sensitization among allergic subjects in northern China is about 13.5%.Correlations of specific IgE antibodies suggest that pollen allergens from Artemisia and Humulus are independent sources for primary sensitization. 相似文献
19.
A .E凌eh of the stotements below 15 fol. fowed by four alternative answers. Ch00Se the one that w0Uld best Corn· Plete the statement and Put the letter in the brackets.10%(C)1 .The term Renaissanee or一ginal}y Indieat- ed_after the dark ages of me- d!evs}ObSCUrsntlsm. A .a trGmendOUS}nterest旧dlfferent forms of}iterstUrG B .8 rev一vs}of dem0C旧tiC ldeas C .a rev一va}ofe!assieala吐5 and Se卜 enCeS D .a re!igious devotlon(A)2 .The greatest ePle Poem In the seeond 卜a、 oft卜e 1 6th… 相似文献
20.
l完形填空A(10分) Men first measuredthe ground.The Iength (3) what time ofEg)rptianS used a pilIar,of the dav (5)(1)(2)lt waSusing a stick in shadow would(4) ,the(5)(6)as a gnOmOn,aJld thell (7)deve【0ped a simpk sundial, (6) 00nsisted of a stonewith a pOinter on it.The stone waS placed in￡u1 east—weSt (8)directIOn,a11d the shadow of the pointer showed the tinle. About 300 BC,a Babylonianvented a semi—circular sundial。(7)(8)BerOsus in一 (9)he markedtwelVe hours.The Babylonians,like… 相似文献