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1.
荧光分子探针技术在表达分子间识别行为及复杂生命和环境体系的内状态信息方面具有非常优异的性能,氧杂蒽及其衍生物螺连隐色体结构变化伴随的分子荧光变换模型,广泛且深入的应用于构建新型功能光敏探针分子.近年来此类探针的合成设计及功能化调控研究异常活跃,新的突破不断涌现.综述了新近基于氧杂蒽及其衍生物的荧光探针在金属阳离子、pH、阴离子识别检测方面的研究进展,并简要阐释了该类探针分子的构筑,识别检测机理以及探针在生物成像和环境监测等方面的应用.  相似文献   
2.
For the injector Scheme-Ⅰ test stand of the China-ADS (Accelerator Driven subcritical System), a beam with the maximum power of 100 kW will be produced and transported to the beam dump. To solve the very high thermal load problem at the dump, two measures are taken to deal with the huge power density at the target. One is to enlarge the contact area between the beam and the target, and this is to be accomplished by expanding the beam profile at the target and using slanted target plates. The other is to produce a more homogenous beam profile at the target to minimize the maximum power density. Here the beam dump line is designed to meet the requirement of beam expansion and homogenization at 3 different energies (3.2 MeV, 5 MeV and 10 MeV), and the step-like field magnets are employed for the beam spot homogenization. Taking into account the fact that the space charge effects are very strong at such low beam energies, the simulations have included space charge effects and errors which show that the beam line can meet the requirements very well. In the meantime, the alternative beam design using standard multipole magnets is also presented.  相似文献   
3.
杨征  马松华  方建平 《中国物理 B》2011,20(6):60506-060506
By improved projective equation approach and a linear variable separation approach, a new family of exact solutions of the (2+1)-dimensional Boiti-Leon-Pempinelli (BLP) system is derived. Based on the derived solitary wave solution, some dromion and solitoff excitations and chaotic behaviours are investigated.  相似文献   
4.
For the injector Scheme- test stand of the China-ADS(Accelerator Driven subcritical System), a beam with the maximum power of 100 k W will be produced and transported to the beam dump. To solve the very high thermal load problem at the dump, two measures are taken to deal with the huge power density at the target.One is to enlarge the contact area between the beam and the target, and this is to be accomplished by expanding the beam profile at the target and using slanted target plates. The other is to produce a more homogenous beam profile at the target to minimize the maximum power density. Here the beam dump line is designed to meet the requirement of beam expansion and homogenization at 3 different energies(3.2 Me V, 5 Me V and 10 Me V), and the step-like field magnets are employed for the beam spot homogenization. Taking into account the fact that the space charge effects are very strong at such low beam energies, the simulations have included space charge effects and errors which show that the beam line can meet the requirements very well. In the meantime, the alternative beam design using standard multipole magnets is also presented.  相似文献   
5.
Three new kinds of acylhydrazone compounds(C_(12)H_(10)FN_5O·H_2O,1;C_(12)H_(10)Cl N_5O·2CH_3COOH,2;C_(12)H_(10)Br N_5O,3)were synthesized by the reaction of 2-amino-3-pyrazinecarbohydrazide(C_5H_7N_5O)with halogenated benzaldehyde(C_7H_5OX,X=F,Cl,Br).The structures of the three compounds were characterized by elemental analysis,~1H NMR,IR and X-ray diffraction.X-ray single-crystal diffraction presents that the three compounds all belong to triclinic system,P1 space group.Thermal gravity analyses show that three compounds have excellent thermal stabilities and all the thermal decomposition temperature of maximum weight loss was around 300°C.The interactions of the compounds with CT-DNA were investigated by UV-Vis spectrum,fluorescence spectrum and viscosity measurement.All the results suggest that three compounds could bind with CT-DNA through intercalation.The fluorescence spectrum was also used to study the interactions of three compounds with BSA.It was proved that all the compounds could quench the intrinsic fluorescence of BSA via a static quenching process.Compound 2 displays the strongest binding ability both in the reaction with CT-DNA or BSA.Antimicrobial test was carried on Escherichia coli,Staphylococcus aureus and Salmonella,and 2 is more effective against S.aureus.But in MTT assay,1 shows better cytotoxity activity against A549cells.  相似文献   
6.
Three new halogenated pyridyl hydrazones, namely 4-chlorobenzaldehyde-4-chloropyridine-2-formyl acylhydrazone(C(13)H9Cl2N3O, 3 a), 4-bromobenzaldehyde-4-chloropyridine-2-formyl acylhydrazone(C(13)H9BrClN3O, 3 b) and 4-iodobenzaldehyde-4-chloropyridine-2-formyl acylhydrazone(C(13)H9ClIN3O, 3 c), have been synthesized and characterized by elemental analysis, IR, 1 H NMR, and single-crystal X-ray diffraction. The X-ray diffraction analysis revealed that 3 a^3 c crystallize in monoclinic with space group Cc. The units of 3 a ~ 3 c were linked by intermolecular N–H...X(X = Cl, Br, I) hydrogen bonds into 2 D layered structures, which were further extended into 3 D networks by a series of π-π stacking interactions. Thermogravimetric analysis showed that all of them possessed higher thermal stabilities. The reactivities toward calf thymus DNA(ct-DNA) and bovine serum albumin(BSA) of 3 a^3 c were investigated by UV-vis and fluorescent spectroscopy as well as molecular docking simulation. Both theoretical and experimental results indicated that 3 a^3 c bound to ct-DNA in the mode of minor groove binding, and interacted with BSA through the hydrophobic cavity near TRP213. Besides, the orders of binding affinities of 3 a^3 c to ct-DNA and BSA were both 3 c > 3 b > 3 a, which were the same as that of antibacterial activities. Thus, the interactions of iodinated acylhydrazone with biological targets were stronger than that of chlorinated and brominated acylhydrazones, which provided a representative case for halogenation of lead compounds in rational drug design.  相似文献   
7.
利用SDS-聚丙烯酰胺凝胶电泳方法分析了水稻孢子体雄性不育系珍汕97A、保持系珍汕97B、F1代汕优63和配子体雄性不育系丛广41A、保持系丛广41B、F1代广优青在小孢子败育时期的花药线粒体蛋白质.结果表明,在这两种类型的组合中,不育系同保持系、F1代的带型差异很大,保持系的带型和F1代的带型差异较小.其中,汕优63比珍汕97B多1条分子量为31000的多肽带,广优青比丛广41B多1条分子量为43300多肽带.  相似文献   
8.
利用Riccati方程映射法和变量分离法,得到了推广的(2+1)维浅水波系统的变量分离解(包括孤波解、周期波解和有理函数解).根据得到的孤波解,构造出了方程的单孤子和双孤子结构,研究了孤子的混沌行为.  相似文献   
9.
以人的抑癌基因bcl-2为探针,通过Southern杂交技术,发现bcl-2在玉米和水稻的基因组中均具有同源序列;并运用荧光原位杂交技术,对玉米中的bcl-2同源序列进行了定位.结果表明:bcl-2在玉米第4号和第7号染色体上均检出了杂交信号,信号检出率分别为8.16%和6.63%.bcl-2在第4号染色体长臂上的杂交信号与着丝粒的百分距离为58.07±4.90,在第7号染色体长臂上的杂交信号与着丝粒的百分距离为80.34±3.12.上述研究结果为研究植物细胞程序性死亡的可能调控机制提供了线索,将有利于进一步分析植物与动物细胞程序性死亡的相关性  相似文献   
10.
CaF2:Ho3+/Yb3+ nano-particles with intense green up-conversion (UC) luminescence are successfully synthesized via a facile hydrothermal approach by using NH4F as the fluoride source and Na2EDTA as a chelating reagent. Powder X- ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), and UC emission spectra are used to characterize the structures, shapes, and luminescent properties of the samples. The effects from fluoride sources and chelating reagents on the formations of CaF2 nano-particles are investigated, and the for- mation process is also deduced. Under the excitation of a 980-nm laser diode, the samples each show a green up-conversion emission centered at 540 nm corresponding to the 5S2/5F4-+518 transitions of Ho3+. Moreover, the UC mechanisms of Ho3+/Yb3+ co-doped CaF2 nano-particles are also discussed.  相似文献   
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