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481.
482.
Broadband Light‐Harvesting Molecular Triads with High FRET Efficiency Based on the Coumarin–Rhodamine–BODIPY Platform 下载免费PDF全文
Longwei He Sasa Zhu Dr. Yong Liu Yinan Xie Qiuyan Xu Haipeng Wei Prof. Weiying Lin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(34):12181-12187
Broadband capturing and FRET‐based light‐harvesting molecular triads, CRBs, based on the coumarin–rhodamine–BODIPY platform were rationally designed and synthesized. The absorption band of CRBs starts from blue–green to yellow–orange regions (330–610 nm), covering the strong radiation scope of sunlight. The peripheral coumarin and BODIPY chromophore energy could transfer to the central acceptor rhodamine by a one‐step direct way. The energy of the coumarin moiety could also transfer to the BODIPY unit, subsequently transferring to the rhodamine core by two‐step sequential ways. Both the efficiencies of the coumarin moiety and the BODIPY unit to the rhodamine core in CRBs, determined by two different ways, are very high. 相似文献
483.
Sequential Logic Operations with a Molecular Keypad Lock with Four Inputs and Dual Fluorescence Outputs 下载免费PDF全文
Dr. Xiong‐Jie Jiang Prof. Dennis K. P. Ng 《Angewandte Chemie (International ed. in English)》2014,53(39):10481-10484
A novel coumarin–rhodamine conjugate was prepared, and its metal binding properties were studied by UV/Vis and fluorescence spectroscopy. The conjugate serves as a ratiometric and highly selective fluorescent sensor for Hg2+ ions. Its metal‐responsive spectral properties were utilized to construct a molecular keypad lock with four inputs and dual fluorescence outputs. The complexity of this molecular logic network can greatly enhance the security level of this device. 相似文献
484.
Mert Olgun Karata Gamze algn Bülent Alc Baak Gke Nahit Gener Tuba Takn Tok Oktay Arslan In Kl‐Ckla Namk
zdemir 《应用有机金属化学》2019,33(10)
We synthesized three coumarin‐substituted benzimidazolium chlorides and their silver(I), ruthenium(II) and palladium(II) N‐heterocyclic carbene (NHC) complexes. All compounds were characterized using appropriate spectroscopic techniques and elemental analyses. Single‐crystal X‐ray structure of a Pd(II)–NHC complex ( 6b ) was also determined. The inhibitory properties of all compounds were tested on the activity of human paraoxonase 1 (PON1). All complexes exhibited weaker inhibitory properties than their corresponding benzimidazolium salts except for complex 6b which is the most active inhibitor with an IC50 value of 3.01 μM among the compounds reported in this study. A kinetic evaluation showed that this complex inhibits PON1 activity in a non‐competitive manner. Molecular docking studies were also performed for 6b in order to obtain more insight into the binding mode. 相似文献
485.
Nanomagnetic bisethylferrocene‐containing ionic liquid supported on silica‐coated iron oxide (Fe3O4@SiO2@Im‐bisethylFc [HC2O4]) as a novel catalyst was designed and synthesized. The described catalyst was recycled and used without change in the time and efficiency of the condensation reaction. The Fourier transform‐infrared spectroscopy (FT‐IR), scanning electron microscopy images, X‐ray diffraction patterns, energy‐dispersive X‐ray spectroscopy, transmission electron microscope and vibrating‐sample magnetometer results confirmed the formation of Fe3O4@SiO2@Im‐bisethylFc [HC2O4] magnetic nanoparticle. The novel bis‐coumarin derivatives were identified by 1H‐NMR, 13C‐NMR, FT‐IR and CHNS analysis. 相似文献
486.
为寻找具有杀菌活性的三唑类先导化合物,采用活性亚结构拼接方法,将香豆素环和硫醚结构单元引入到三唑类化合物分子中,合成一系列未见文献报道的新型含香豆素环和硫醚结构的三唑类衍生物。经~1H NMR、~(13)C NMR、IR、MS和元素分析对所合成化合物的结构进行了表征。初步生物活性测试表明,部分目标化合物在试验浓度下具有一定的抑菌活性。 相似文献
487.
本文合成了3-乙酰基-8-叔丁基香豆素,并通过X-射线单晶衍射法测定分子结构,随后进行红外、核磁共振、紫外可见吸收光谱表征,并通过密度泛函理论(DFT)研究晶体中的分子间作用,模拟光谱并预测表面活性位点。结果表明,分子为大共轭平面结构,在晶体中主要以π-π堆积作用和氢键作用结合,结合能分别为17. 2和3. 9 kcal/mol。分子在近紫外可见光范围内的最大吸收波长在310nm,摩尔消光系数为16000L·mol-1·cm-1,主要对应苯环上π电子向内酯环以及羰基氧上的跃迁。该分子6号位碳最易发生芳环上亲电取代反应,内酯可发生水解、氨解等反应,苯环上氢、羰基氧均可形成氢键等弱相互作用。 相似文献
488.
In this study, synthesis of new ligands, 8-hydroxy-3-[p-(3′,4′-dicyanophenoxy)-phenyl]coumarin and 8-hexyloxy-3-[p-(3′,4′-dicyanophenoxy)-phenyl]coumarin, and their phthalocyanines, 2,9,16,23-tetrakis[8-hexyloxy-3-(4-oxyphenyl)coumarin]-metal-free and metallophthalocyanines {M[Pc(OBzCou)4] (M = 2H, Zn(II), Co(II); Bz: benzene; Cou: coumarin)} were synthesised. The novel chromogenic compounds were characterised by elemental analysis: 1H NMR, 13C NMR, MALDI-TOF, IR and UV–vis spectral data. The effect of coumarin substituents on the photophysical properties of metal-free (H2Pc) and zinc phthalocyanines (ZnPc) derivatives has been examined. Spectrophotometric measurements revealed that coumarin-substituted ZnPc derivatives were in the unaggregated form, whereas those of H2Pc species were in aggregated form. It means that substitution of coumarin derivative prevents the cluster formation in the presence of zinc ion in the centre of Pc. 相似文献
489.
490.
A new phenolic glycoside, citrauranoside A (1), and two new monoterpenoid furocoumarins, citraurancoumarin A (2) and citraurancoumarin B (3), along with four known compounds (4–7) were isolated from the young fruit of Citrus aurantium L. The structures were elucidated by their comprehensive analysis including 1D, 2DNMR, IR and mass spectra. 相似文献