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Electron Concentration Dependence of Transformation Temperature in Different NiMnGa Alloys with First Order Magnetic Transition
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作者 Duan Jingfang Zhang Zeyu Wang Dong Long Yi YeRongchang Chang Yongqin 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第4期I0012-I0012,共1页
Composition and electron concentration dependence of transformation temperature in Ni2+x+y Mn1-xGa1-y, Ni2+x Mn1-x Ga alloys with first order magnetic transition were studied. For Ni2 + x + y Mn1- x Ga1-y alloys,... Composition and electron concentration dependence of transformation temperature in Ni2+x+y Mn1-xGa1-y, Ni2+x Mn1-x Ga alloys with first order magnetic transition were studied. For Ni2 + x + y Mn1- x Ga1-y alloys, martensitic transformation temperature TM increases and Curie temperature Tc decreases with the increase of electron concentration e/a, they intercept at e/a = 7.68. TM and Tc decrease when continue to increase electron concentration. While for Ni2+x Mn1-xGa alloys, they cross at e/a = 7. 635. Before their crossing, the change tendency with e/a is the same as Ni2+x+yMn1-xGa1-y alloys;, after their crossing, both TM and Tc increase slowly. The different relations between TM and Tc and e/a within two NiMnGa alloys show that TM and Tc depend not only on e/a, but also on composition. 展开更多
关键词 NiMnGa alloys electron concentration (e/a) martensitic transformation magnetic transition rare earths
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Molecular Epidemiological Analysis of Echovirus 19 Isolated From an Outbreak Associated With Hand, Foot, and Mouth Disease (HFMD) in Shandong Province of China 被引量:22
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作者 ZHEN ZHU WEN-BO XU +6 位作者 AI-QIANG XU HAI-YAN WANG YONG ZHANG LI-ZHI SONG Hui-LiYANG YANLI FENGJI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2007年第4期321-328,共8页
To elucidate the genetic characterization and molecular epidemiological features of Echovirus 19 (El9) isolates collected from an outbreak associated with hand, foot and mouth disease (HFMD) in Tai'an city of Sha... To elucidate the genetic characterization and molecular epidemiological features of Echovirus 19 (El9) isolates collected from an outbreak associated with hand, foot and mouth disease (HFMD) in Tai'an city of Shandong Province of China from July to September, 2003. Methods Thirty seven Echovirus 19 isolates were isolated from stool specimens and throat swabs collected during the outbreak, then major capsid (VP1) genomic sequence was determined, and phylogenetic tree was done based on the VP1 sequences among these 37 and other El9 viruses deposited in the Genbank. Also a representative strain named CHN-SD03-TN12 was selected for sequencing of 5′-untranslated regions (5′-UTR). Results The identity rate was about 98.9%-100% among all these 37 El9 viruses. The genetic relationships between these 37 El9 isolates and other strains reported were also depicted. The identity rate was about 78.4%-78.9% compared with El9 reference strain Burke. The substitutions in the sequence of 5′-UTR resulted in changes in the conjectural properties of 5′-UTR of El9 viruses. Condusion The genetic features of El9 viruses isolated during the outbreak in Shandong Province in 2003 may be associated with a genetic and antigenic drift that changes the virulence of the Shandong isolates, but the molecular changes in Shandong El9 viruses contributing to their phenotype remain to be further illuminated. However, the sequences described in this paper substantiate the changes taken place in capsid VPI and 5′UTR regions. These substitutions may contribute to their tropism and virulence, and play a significant role in pathogenesis and clinical manifestations of the disease. 展开更多
关键词 enterovirus 19(e19) Hand foot and mouth disease (HFMD) Molecular epidemiology 5′ Untranslated regions(5′-UTR) B-C loop
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Electron Momentum Spectroscopy of Outer Valence Orbitals of 2-Fluoroethanol
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作者 史钰峰 单旭 +3 位作者 王恩亮 阳弘江 张卫 陈向军 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第1期35-42,I0001,共9页
The binding energy spectra and electron momentum distributions for the outer valence molecular orbitals of gaseous 2-fluoroethanol have been measured by the non-coplanar asym- metric (e, 2e) spectrometer at impact e... The binding energy spectra and electron momentum distributions for the outer valence molecular orbitals of gaseous 2-fluoroethanol have been measured by the non-coplanar asym- metric (e, 2e) spectrometer at impact energy of 2.5 keV plus binding energy. The quantitative calculations of the ionization energies and the relevant molecular orbitals have been carried out by using the outer-valence Green's function method and the density functional theory with B3LYP hybrid functional. The observed ionization bands in binding energy spectra, as well as the previous photoelectron spectrum which was not assigned, have been assigned for the first time through the comparison between experiment and theory. In general, the the- oretical electron momentum distributions calculated by B3LYP method with aug-cc-pVTZ basis set are in line with the experimental ones when taking into account the Boltzmann- weighted thermo-statistical abundances of five conformers of 2-fluoroethanol. 展开更多
关键词 (e 2e electron momentum spectroscopy 2-Fluoroethanol CONFORMeR Densityfunctional theory
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Steroid sex hormone dynamics during estradiol-17β induced gonadal differentiation in Paralichthys olivaceus(Teleostei) 被引量:3
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作者 孙鹏 尤锋 +5 位作者 刘梦侠 吴志昊 文爱韵 李军 徐永立 张培军 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第2期254-259,共6页
Steroid sex hormones, such as estradiol-17β (E2) and testosterone (T), are important regulators of sex change in fish. In this study, we examined the effects of E2 treatment on the dynamics of E2 and T during gon... Steroid sex hormones, such as estradiol-17β (E2) and testosterone (T), are important regulators of sex change in fish. In this study, we examined the effects of E2 treatment on the dynamics of E2 and T during gonadal differentiation in the olive flounder Paralichtbys olivaceus using histology and radioimmunoassay (RIA). Flounder larvae were divided into five groups (G0~G4), and fed with 0 (control), 0.2, 2, 20 and 100 mg E2/kg feed from 35 to 110 day post hatching (dph). Fish growth in the G1 and G2 groups was not significantly different from that of the control group (P〉0.05), while fish in the G3 and G4 groups were less active and showed growth depression and high mortality. The gonads of fish in the G3 and G4 groups were smaller and surrounded by hyperplastic connective tissue. The frequency of females in the G0-G4 groups was 54.5%, 75.0%, 100%, 100% and 93.3%, respectively. The RIA analyses of E2 and T showed that T levels decreased during gonadal differentiation, and increased slightly at the onset of ovarian differentiation, while E2 levels increased gradually and peaked at the onset of ovarian differentiation in the control group. In the E2-treated groups, T levels decreased before the onset of ovarian differentiation. E2 levels were high on the 48 dph, but declined to a lower level on the 54 dph, and then increased gradually during gonadal differentiation. And a sharp increase of E2 levels were observed in all E2-treated groups at the onset of ovarian differentiation. The data suggest that T and E2 play important roles during gonadal differentiation, and an E2 dose of 2 mg/kg feed could induce sex reversal in P olivaceus. 展开更多
关键词 olive flounder gonadal differentiation estradiol-17β (e2) testosterone (T) exogenous e2 treatment
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Synthesis, Crystal Structure and Antitumor Activity of (E)-4-tert-Butyl-N-(2,4-dichlorobenzylidene)-5-(1,2,4-triazol-1-yl)-thiazol-2-amine 被引量:5
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作者 胡艾希 覃智 +1 位作者 叶姣 夏曙 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第11期1680-1683,共4页
The title compound (E)-4-tert-butyl-N-(2,4-dichlorobenzylidene)-5-(1,2,4-triazol-1-yl)-thiazol-2-amine was synthesized by the reaction of 4-tert-butyl-5-(1,2,4-triazol-1-yl)-thiazol-2-amine with 2,4-dichlorobe... The title compound (E)-4-tert-butyl-N-(2,4-dichlorobenzylidene)-5-(1,2,4-triazol-1-yl)-thiazol-2-amine was synthesized by the reaction of 4-tert-butyl-5-(1,2,4-triazol-1-yl)-thiazol-2-amine with 2,4-dichlorobenzaldehyde, and its crystal structure was determined by singlecrystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with a = 7.9748(4), b = 10.1803(5), c = 11.4603(6), α = 102.882(1), β = 100.253(1), γ = 104.457(1)°, V = 850.95(7)3, Z = 2, F(000) = 392, C16H15Cl2N5S, Mr = 380.29, Dc = 1.484 g/cm3, S = 1.095, μ = 0.512 mm-1, the final R = 0.0301 and wR = 0.0965 for 3334 observed reflections (I 〉 2σ(I)). The preliminary antitumor activity shows that for the title compound the IC50 of Hela is 0.175 μmol/mL and that of Bel7402 is 0.156 μmol/mL. 展开更多
关键词 (e)-4-tert-butyl-N-(2 4-dichorobenzylidene)-5-(1 2 4-triazl-1-yl)-thiazol-2-amine crystal structure synthesis antitumor activity
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Dietary lipid and gross energy affect protein utilization in the rare minnow Gobiocypris rarus 被引量:2
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作者 吴本丽 熊小琴 +1 位作者 解绶启 王剑伟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第4期740-748,共9页
An 8-week feeding trial was conducted to detect the optimal dietary protein and energy, as well as the ef fects of protein to energy ratio on growth, for the rare minnow( Gobiocypris rarus), which are critical to nutr... An 8-week feeding trial was conducted to detect the optimal dietary protein and energy, as well as the ef fects of protein to energy ratio on growth, for the rare minnow( Gobiocypris rarus), which are critical to nutrition standardization for model fi sh. Twenty-four diets were formulated to contain three gross energy(10, 12.5, 15 kJ/g), four protein(20%, 25%, 30%, 35%), and two lipid levels(3%, 6%). The results showed that optimal dietary E/P was 41.7–50 kJ/g for maximum growth in juvenile rare minnows at 6% dietary crude lipid. At 3% dietary lipid, specifi c growth rate(SGR) increased markedly when E/P decreased from 62.5 kJ/g to 35.7 kJ/g and gross energy was 12.5 kJ/g, and from 75 kJ/g to 42.9 kJ/g when gross energy was 15.0 kJ/g. The optimal gross energy was estimated at 12.5 kJ /g and excess energy decreased food intake and growth. Dietary lipid exhibited an apparent protein-sparing eff ect. Optimal protein decreased from 35% to 25%–30% with an increase in dietary lipid from 3% to 6% without adversely ef fecting growth. Dietary lipid level af fects the optimal dietary E/P ratio. In conclusion, recommended dietary protein and energy for rare minnow are 20%–35% and 10–12.5 k J/g, respectively. 展开更多
关键词 rare minnow Gobiocypris rarus protein to energy ratio(e/P) crude lipid GROWTH
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Synthesis,Crystal Structure and Fungicidal Activity of(E)-2-[(4-tert-Butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)methyl]phenol 被引量:2
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作者 胡艾希 曹高 +2 位作者 马颍绮 张建宇 欧晓明 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第10期1235-1239,共5页
The title compound (E)-2-[(4-tert-butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)methyl]phenol was synthesized by the reaction of 5-(4-methoxybenzyl)-4-tert- butylthiazol-2-amine with salicylaldehyde, and its crys... The title compound (E)-2-[(4-tert-butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)methyl]phenol was synthesized by the reaction of 5-(4-methoxybenzyl)-4-tert- butylthiazol-2-amine with salicylaldehyde, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 5.9362(8), b = 11.5070(15), c = 29.460(4)A, β= 97.326(3)°, V = 1995.9(5) A^3, Z = 4, F(000) = 808, C22H24N2O2S, Mr= 380.49, De= 1.266 g/cm^3, S = 1.031,μ = 0.181 mm^-1, the final R = 0.0474 and wR = 0.1441 for 4327 observed reflections (I 〉 2σ(I)). Intramolecular O-H…N hydrogen bond is observed in the crystal. The preliminary bioassay showed that the title compound exhibits 95% inhibition rate against Rhizoctonia solani at the test concentration of 500 mg/L. 展开更多
关键词 crystal structure SYNTHeSIS fungicidal activity (e)-2- [(4-tert-butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)methyl]phenol
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Functional characterization of(E)-β-caryophyllene synthase from lima bean and its up-regulation by spider mites and alamethicin 被引量:1
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作者 LI Feng-qi FU Ning-ning +1 位作者 ZHOU Jing-jiang WANG Gui-rong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第10期2231-2238,共8页
(E)-β-Caryophyllene is a sesquiterpene compound widely distributed in plants and functions in plant defence. However, little is known about the sequence and function of (E)-β-caryophyllene synthase in lima bean ... (E)-β-Caryophyllene is a sesquiterpene compound widely distributed in plants and functions in plant defence. However, little is known about the sequence and function of (E)-β-caryophyllene synthase in lima bean (Phaseolus lunatus). Here, we report a new full-length cDNA (PICAHS) encoding (E)-β-caryophyllene synthase, a possible key enzyme of plant defence. The cDNA of PICAHS contains an open reading frame of 1 761 bp, encoding a protein of 586 amino acids with a predicted mass of 67.95 kDa. The deduced amino acid sequence shows 52% identity with sesquiterpene synthase MtCAHS of Med- icago truncatula. Based on phylogenetic analysis, PICAHS is classified as the terpene synthases (TPS)-a subfamily. The recombinant enzyme, expressed in Escherichia coil, catalysed the formation of a major product (E)-β-caryophyllene (82%) and a minor product a-humulene (18%) from farnesyl dJphosphate. Real-time quantitative PCR (qRT-PCR) analysis found that the PICAHS transcript was significantly up-regulated in leaves after treatment with spider mites and alamethicin (ALA), suggesting its ecological function in plant defence. 展开更多
关键词 plant defence terpene synthases (e)--caryophyllene lima bean
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Synthesis,Crystal Structure and DNA-binding Properties of a New Copper(Ⅱ) Schiff Base Complex 被引量:1
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作者 秦蓓 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第8期1187-1193,共7页
A new asymmetric bidentate copper(Ⅱ) complex,CuL 2(HL=2-((E)-(4-bromophenylimino)methyl)-6-bromo-4-chlorophenol),has been synthesized and characterized by elemental analyses and single-crystal X-ray diffrac... A new asymmetric bidentate copper(Ⅱ) complex,CuL 2(HL=2-((E)-(4-bromophenylimino)methyl)-6-bromo-4-chlorophenol),has been synthesized and characterized by elemental analyses and single-crystal X-ray diffraction.The complex crystallizes in the monoclinic space group P2 1 /c with a=11.218(3),b=9.355(3),c=13.449(4),β=108.722(4)°,V=1336.8(6)3,Z=2,Dc=2.008 g/cm 3,μ(MoKα)=7.024 mm-1,F(000)=806,S=0.999,the final R=0.0342 and wR=0.0641for2611observed reflections (I〉2σ(I)).The central copper(Ⅱ) is four-coordinate and bonds to two nitrogen and two oxygen atoms from two Schiff base ligands.The complex is linked into a two-dimensional supramolecular structure by weak intermolecular interactions.In addition,DNA-binding properties of the metal complex were investigated using spectrometric titrations and viscosity measurements.The results show that the complex binds with calf-thymus DNA(CT-DNA),presumably via a partial intercalative mode.The intrinsic binding constant of the Cu(Ⅱ) complex with DNA is 7.335×10 3 M-1. 展开更多
关键词 crystal structure 2-((e)-(4-bromophenylimino)methyl)-6-bromo-4-chlorophenol copper(Ⅱ) complex calf-thymus DNA partial intercalative mode
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The (e,2e) triple differential cross sections of Cu^+ (3p) in coplanar asymmetric geometry
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作者 周丽霞 燕友果 门福殿 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第7期204-209,共6页
The three-body distorted=wave Born approximation has been used to calculate the (e, 2e) triple differential cross sections (TDCSs) of Cu+ (3p) in different kinematical variables in coplanar asymmetric geometry.... The three-body distorted=wave Born approximation has been used to calculate the (e, 2e) triple differential cross sections (TDCSs) of Cu+ (3p) in different kinematical variables in coplanar asymmetric geometry. The angles 4°, 10° and 20° were selected as the scattering electron angles. Under high incident energy (≥500 eV) and high asymmetric detection energy, the binary peaks showed abnormal splits. Such abnormal splits have not been observed in atomic target and outer valence orbitals of ionic target, which indicates that an (e, 2e) process for inner valence orbitals of ionic target would be more complicated than outer valence orbitals. Furthermore, some pronounced peaks appeared at certain ejected angles. We considered that these pronounced peaks are probably related to one kind of double-binary collision. 展开更多
关键词 (e 2e distorted-wave Born approximation triple differential cross sections double-binary collision
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UV-TiO_2 photocatalytic disinfection and photoreactivation of pathogenic bacterium in municipal wastewater
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作者 王西峰 胡晓莲 +1 位作者 龚昕 班云霄 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第12期3115-3121,共7页
The disinfected bacteria will be a photoreactivation under the irradiation of the sunlight,and the light intensity plays an important role in the bacteria resurrection.The effect of light intensity on photoreactivatio... The disinfected bacteria will be a photoreactivation under the irradiation of the sunlight,and the light intensity plays an important role in the bacteria resurrection.The effect of light intensity on photoreactivation of Escherichia coli(E.coli) and Enterococcus faecalis(E.faecalis) in secondary effluents which were disinfected respectively by pure UV and UV-TiO_2 was investigated.The results show that the disinfection efficiency of UV-TiO_2 is much higher than that of the pure UV disinfection.The photoreactivation rate of E.coli is much higher in pure UV disinfection than in UV-TiO_2 photocatalytic disinfection.Under high light intensity in UV-TiO_2 disinfection,high resurrection rate can be induced.However,a higher resurrection rate can be introduced even under low light intensity in pure UV disinfection alone.Meanwhile,UV-TiO_2 disinfection has a strong inhibition effect on E.faecalis photoreactivation.When the light intensity is lower than 21 μW/cm^2,nearly no resurrection of E.faecalis occurs after 72 h resurrection irradiation,and a little resurrection rate is observed only under a strong photoreactivating light intensity. 展开更多
关键词 pathogenic bacteria inactivate UV-TiO2 disinfection PHOTOReACTIVATION escherichia coli (e. coli) enterococcusfaecalis (e. facialis)
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Polarization effect in(e,2e) reaction process for Ar(3s) in coplanar asymmetric geometry
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作者 周丽霞 王殿生 +1 位作者 燕友果 王彩玲 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第11期268-272,共5页
The (e, 2e) triple differential cross sections (TDCSs) of Ar (3s) are calculated by using distorted-wave Born approx- imation under coplanar asymmetric geometry. The incident electron energy is 113.5 eV, and the... The (e, 2e) triple differential cross sections (TDCSs) of Ar (3s) are calculated by using distorted-wave Born approx- imation under coplanar asymmetric geometry. The incident electron energy is 113.5 eV, and the scattering electron angle 01 is -15~. The ejected electron energy is set at 10 eV, 7.5 eV, 5 eV, and 2 eV, respectively. The polarization effects have been discussed and the polarization potential Vpol changing from a second-order to a fourth-order term has been analyzed. Our calculated TDCSs have been compared with reported experimental and theoretical results, and the calculated TDCSs of polarization potential up to the fourth order could give a good fit with experimental results in the binary region, but fail to predict the correct recoil-to-binary ratio in most cases. 展开更多
关键词 (e 2e reaction distorted-wave Born approximation triple differential cross sections polarizationeffect
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Second-order Born calculation of coplanar symmetric(e, 2e) process on Mg
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作者 张永志 王旸 周雅君 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第6期177-180,共4页
The second-order distorted wave Born aPl6roximation (DWBA) method is employed to investigate the triple differen- tial cross sections (TDCS) of coplanar doubly symmetric (e, 2e) collisions for magnesium at exces... The second-order distorted wave Born aPl6roximation (DWBA) method is employed to investigate the triple differen- tial cross sections (TDCS) of coplanar doubly symmetric (e, 2e) collisions for magnesium at excess energies of 6 eV-20 eV. Comparing with the standard first-order DWBA calculations, the inclusion of the second-order Born term in the scattering amplitude improves the degree of agreement with experiments, especially for backward scattering region of TDCS. This indicates that the present second-order Born term is capable to give a reasonable correction to DWBA model in studying coplanar symmetric (e, 2e) problems of two-valence-electron target in low energy range. 展开更多
关键词 second-order Born approximation (e 2e collisions MAGNeSIUM triple differential cross section
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Electron Momentum Distributions for 4a1 Orbitals of CFxCl4-x in Low Momentum Region: a Possible Evidence of Molecular Geometry Distortion
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作者 Xu Shan Chun-kai Xu +3 位作者 Xiao-feng Yin Li-xia Zhou Ke-zun Xu Xiang-jun Chen 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第6期642-648,J0002,共8页
Electron momentum distributions for 4a1 orbitals of serial freon molecules CFaC1, CF2Cl2, and CFCl3 (CFxC14-x, x=1-3) have been reanalyzed due to the severe discrepancies between theory and experiment in low momentu... Electron momentum distributions for 4a1 orbitals of serial freon molecules CFaC1, CF2Cl2, and CFCl3 (CFxC14-x, x=1-3) have been reanalyzed due to the severe discrepancies between theory and experiment in low momentum region. The tentative calculations using equilibrium geometries of molecular ions have exhibited a great improvement in agreement with the experimental data, which suggests that the molecular geometry distortion may be responsible for the observed high intensities at p〈0.5 a.u.. Further analyses show that the severe discrepancies at low momentum region mainly arise from the influence of molecular geometry distortion on C-Cl bonding electron density distributions. 展开更多
关键词 (e 2e electron momentum spectroscopy Molecular geometry distortion electron density distribution
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A Facile Stereospecific Synthesis of 1, 3-Enynylsulfides via Sonogashira Coupling of (E)-a-Iodovinyl Sulfides with 1-Alkynes
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作者 Jian Wen JIANG Ming Zhong CAI 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第6期757-760,共4页
(E)-α-Iodovinyl sulfides 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol % of Pd(PPh3)4 and 10 mol % of CuI to afford the correspo... (E)-α-Iodovinyl sulfides 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol % of Pd(PPh3)4 and 10 mol % of CuI to afford the corresponding 1, 3-enynylsulfides 3 stereospecifically in high yields. 展开更多
关键词 (e)-α-Iodovinyl sulfide 1 3-enynylsulfide Sonogashira coupling terminal alkyne.
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Convenient one-pot synthesis of functionalized (E)-2-arylvinyl bromides from (E)-4-(2-bromovinyl)phenyl acetate
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作者 Yu Bo Jiang Chun Xiang Kuang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第5期545-548,共4页
A convenient one-pot synthesis of functionalized (E)-2-arylvinyl bromides was achieved by microwave-induced deacetylation and subsequent acylation using dicyclohexyl carbodiimide (DCC) and dimethylamino-pyridine ... A convenient one-pot synthesis of functionalized (E)-2-arylvinyl bromides was achieved by microwave-induced deacetylation and subsequent acylation using dicyclohexyl carbodiimide (DCC) and dimethylamino-pyridine (DMAP) at room temperature from (E)-4-(2-bromovinyl)phenyl acetate. 展开更多
关键词 One-pot synthesis (e)-2-Arylvinyl bromide ACYLATION DeACeTYLATION
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Triple-differential cross section for single ionization of H_2 by electron impact
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作者 王远成 刘俊伯 +2 位作者 马佳 刘德军 周雅君 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期163-166,共4页
The triple-differential cross section (TDCS) for the (e,2e) ionization of a hydrogen molecule is calculated using the molecule distorted-wave Born approximation (MDWBA). Distorted waves are obtained by solving m... The triple-differential cross section (TDCS) for the (e,2e) ionization of a hydrogen molecule is calculated using the molecule distorted-wave Born approximation (MDWBA). Distorted waves are obtained by solving momentum-space coupled-channel Lippmann-Schwinger equations, including the ground state and the lowest-lying electronic state of b3Σu . TDCSs at the incident energy 100 eV in coplanar asymmetric geometry are reported. The present calculations are compared with the available experimental measurements and the theoretical results. 展开更多
关键词 (e 2e collisions hydrogen molecule triple differential cross section
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(e,2e) triple-differential cross sections for Ag^+ (4p, 4s) in coplanar symmetric geometry
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作者 周丽霞 燕友果 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期204-207,共4页
The (e, 2e) triple-differential cross sections of Ag+ (4p, 4s) are calculated based on the three-body distorted-wave Born approximation considering post-collision interaction in coplanar symmetric geometry. The e... The (e, 2e) triple-differential cross sections of Ag+ (4p, 4s) are calculated based on the three-body distorted-wave Born approximation considering post-collision interaction in coplanar symmetric geometry. The energy of the outgoing electron is set to be 50, 70, 100, 200, 300,500, 700, and 1000 eV, and the intensity and splitting of forward and backward peaks are discussed in detail. Some new structures are observed around 15° and 85° for 4p and 4s orbitals. Structures in triple-differential cross sections at 15° are reported for the first time. A double-binary collision is proposed to explain the formation of such structures. The structures at 85° are also considered as the result of one kind of double-binary collision. 展开更多
关键词 (e 2e process distorted-wave Born approximation triple-differential cross section coplanar symmetric geometry
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Electron impact ionization of neon and neonic ions under distorted-wave Born approximation
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作者 周丽霞 燕友果 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第5期249-252,共4页
The (e, 2e) triple differential cross sections of 2s orbitals of neon and neonic ions (Z = 11-14) are calculated using a distorted-wave Born approximation under coplanar asymmetric geometry. The calculated results... The (e, 2e) triple differential cross sections of 2s orbitals of neon and neonic ions (Z = 11-14) are calculated using a distorted-wave Born approximation under coplanar asymmetric geometry. The calculated results show that, with the increase in the nuclear charge number Z, the amplitude of triple differential cross sections decreases. The angle difference between the binary peak position and the direction of momentum transfer gradually increases with the increase in the nuclear charge Z, and a new structure appears at an ejected angle 90° 〈 θ2 〈 120°. Three kinds of collision processes are proposed to illustrate the formation mechanism of such collision peaks. 展开更多
关键词 (e 2e reaction distorted-wave Born approximation triple differential cross sections
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Electro-optical properties and(E,F) phase diagram of fluorinated chiral smectic liquid crystals
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作者 R Zgueb H Dhaouadi T Othman 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第10期570-577,共8页
Fluorinated smectic liquid crystals each with a biphenyl benzoate rigid core are investigated. Molecular structures of the studied compounds have difference only in fluorine position and the length of the carbon chain... Fluorinated smectic liquid crystals each with a biphenyl benzoate rigid core are investigated. Molecular structures of the studied compounds have difference only in fluorine position and the length of the carbon chain. Dielectric relaxation study and electro-optical measurements are carried out with the classical SSFLC geometry. The field-induced phase transitions are studied and the(E,T) phase diagram is established. 展开更多
关键词 smectic liquid crystal dielectric relaxation electro-optical properties phase transition (e T)phase diagram
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