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31.
A novel water-soluble [60] fullerene-substituted lysine derivative 3 has been synthesized and characterized by elemental analysis, 1H NMR, 13C NMR and FAB-MS. The synthetic procedure involved condensation of Boc-protected lysine with terephthaldehyde followed by 1,3-dipolar cycloaddition reaction with C60 in the presence of sarcosine and finally deprotection of the amino group using trifluoroacetic acid. The synthesized compound 3 exhibited high DNA cleavage efficiency upon visible light irradiation in the presence of NADH. 相似文献
32.
ZONG Qianying GENG Huimin YE Lin ZHANG Aiying SHAO Ziqiang FENG Zengguo 《高等学校化学研究》2016,32(3):484-492
Fmoc or Boc mono-substituted cyclo(L-Lys-L-Lys)s were synthesized via the reaction of lysine cyclic dipeptide with Fmoc N-hydroxysuccinimide este(Fmoc-OSu) and di-tert-butyl dicarbonate[(Boc)2O], respectively. The resulted mono-substituted cyclo(L-Lys-L-Lys)s(2-4) by means of test tube inversion method served as organogelators enabled to form stable thermo-reversible organogels in alcoholic, substituted benzene and chlorinated solvents, with the minimum gelation concentration(MGC) in a range of 1%-4%(mass fraction). The transmission electron microscopy(TEM) and scanning electron microscopy(SEM) observations reveal that these gelators self-assembled into 3D nanofiber, nanoribbon or nanotube network structures. The rheological measurement exhibited that the storage modulus of gels is higher than the loss one, and the complex viscosity is reduced linearly with the increasing of scanning frequency. The fluorescence spectrum of compound 2 in 1,2-dichloroethane and benzene demonstrates that the emission peak of Fmoc at 320 nm has red-shifted and the intensity decreases gradually, while the intensity of the emission peak at 460 nm substantially enhances as a function of concentration, indicating the existence of π-π sta- cking interactions and the formation of J-type aggregates. Meanwhile, compound 4 self-assembled into nanotubes via the stacking of multiple bilayer membranes. Fmoc and Boc disubstituted cyclo(L-Lys-L-Lys)(3) holds the relatively lower MGC values, showing the stronger gelation ability in most selected organic solvents due to the presence of both Fmoc and Boc groups. 相似文献
33.
Haihang Zhao Ling Li Yuan Cao Guidong Gong Yangyang Zhou XingXing Gao Lin Pu Gang Zhao 《Tetrahedron letters》2019,60(18):1238-1242
A BINAM-based compound (R)-1 is found to show significant fluorescence enhancement in the presence of Lys in aqueous solution (1%DMF). This probe achieves highly selective fluorescent recognition of Lys even in the presence of other natural amino acids. It can be used as a sensitive as well as selective fluorescent probe for Lys. The mechanism for the interaction of (R)-1 with Lys was studied by NMR and HRMS. 相似文献
34.
35.
2(C12H26O3N3·C2H3O2)·C2H4O2·H2O,M
r
=350.44, triclinic, P1,a=5.576,b=12.574(3),c=14.946(2) Å, =107.80(2), =96.34(2), =89.89(2)°.B=991.04(6) Å3,Z=2,D
x
=1.201 g/cm3, (KCu)=1.5418, Å, =7.4 cm–1, room temperature.R=0.074 for 2645 observed reflections. In the unit cell there are two peptide molecules, three acetic acid molecules, two of them likely to be present as acetate anions, and one water molecule. Each peptide exists in zwitterionic form with the carboxylic group deprotonated, and with positive charges both in the amino terminal and -amino groups of lysine. The two peptide molecules have almost identical conformations. The dipeptide backbone is folded. 相似文献
36.
A covalent modified glassy carbon electrode (GCE) with Lysine (Lys) has been fabricated via an electrochemical oxidation procedure. The electrostatic interaction of the monolayer has been investigated by cyclic voltammetry (CV) with Fe(CN)63? redox probe in different concentrations of protons and different charged cations, respectively. The electrochemical method can be a new feasible method for the study of electrostatic interaction of the monolayer. 相似文献
37.
38.
赖氨酸与邻氯苯甲醛的衍生化反应及其示波极谱法测定 总被引:4,自引:0,他引:4
本文研究了赖氨酸与邻氯苯甲醛的衍生化反应,发现所生成的席夫键产物,在约0.30mol/L的磷酸盐缓冲溶液中(pH11.0),于峰电位-1.12V处,在滴汞电极上产生灵敏吸附还原波。导数波高与赖氨酸浓度在1×10~(-7)mol/L~5×10~(-4)mol/L内有线性关系,检测限为3×10~(-8)mol/L。该方法应用于食品中赖氨酸含量测定,得到满意结果。 相似文献
39.
Esther?Campos GiménezEmail author Thierry?Bénet Lionel?Spack 《Accreditation and quality assurance》2004,9(10):605-614
The measurement uncertainty in the calculation of the amount of blocked and reactive lysine (as determined by the furosine method) was evaluated according to the procedure described in the Eurachem/CITAC guide. The analytical method involves the chromatographic determination of lysine and furosine after acid hydrolysis. The calculation of blocked and reactive lysine in the initial protein is based on known conversion factors. The estimation of the uncertainty was performed in two steps: (1) determination of the uncertainty in the chromatographic determination of lysine and furosine, and (2) determination of the uncertainty in the calculation of blocked and reactive lysine. The individual contributions to the final uncertainty were identified, quantified, and combined in uncertainty budgets. The largest contribution to the calculation of blocked lysine came from estimating the conversion factor of blocked lysine into furosine during acid hydrolysis. For the calculation of reactive lysine, the main contribution came from the chromatographic determination of lysine. The uncertainty estimates were compared to available validation data (in-house and collaborative standard deviations of reproducibility). 相似文献
40.
制备了一种新的基因载体材料———赖氨酸修饰的壳聚糖(CTS-lys)包裹的磁性纳米颗粒. 优化制备了CTS-lys原料, 红外(IR)和核磁(1H-NMR)检测结果表明壳聚糖的大量氨基被赖氨酸修饰. 通过共沉淀方法, 制备了赖氨酸修饰的壳聚糖磁性纳米颗粒(CTS-lys-MNPs). 利用透射电镜(TEM)、激光粒度分析仪、磁力计(VSM)和X射线衍射(XRD)对CTS-lys-MNPs进行了表征, 并通过U293细胞, 研究了CTS-lys-MNPs的细胞毒性. 结果表明, CTS-lys-MNPs的平均粒径为100 nm, 具有较好的超顺磁性和较低的细胞毒性; 在此基础上, 通过凝胶电泳实验观察了CTS-lys-MNPs和DNA的结合情况, 并通过单光子发射型计算机断层显像仪(SPECT) 研究了CTS-lys-MNPs和DNA的复合物在动物体内跨越血脑屏障的能力. 结果表明, CTS-lys-MNPs 是一种较好的磁靶向基因载体并能成功地跨越血脑屏障. 相似文献