全文获取类型
收费全文 | 929篇 |
免费 | 0篇 |
专业分类
化学 | 928篇 |
物理学 | 1篇 |
出版年
2023年 | 1篇 |
2020年 | 28篇 |
2019年 | 84篇 |
2018年 | 20篇 |
2017年 | 77篇 |
2016年 | 16篇 |
2015年 | 18篇 |
2014年 | 15篇 |
2013年 | 18篇 |
2012年 | 60篇 |
2011年 | 54篇 |
2010年 | 34篇 |
2009年 | 26篇 |
2008年 | 42篇 |
2007年 | 37篇 |
2006年 | 48篇 |
2005年 | 53篇 |
2004年 | 41篇 |
2003年 | 38篇 |
2002年 | 29篇 |
2001年 | 42篇 |
2000年 | 37篇 |
1999年 | 24篇 |
1998年 | 29篇 |
1997年 | 19篇 |
1996年 | 24篇 |
1995年 | 15篇 |
排序方式: 共有929条查询结果,搜索用时 821 毫秒
91.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(16):4636-4639
Multicomponent reactions are excellent tools for rapid generation of small molecules with broad chemical diversity and molecular complexity. Herein, a novel one‐pot multicomponent synthesis of β‐amino amides from aldehydes, anilines, carboxylic acids and ynamides has been successfully developed. This process is practical and efficient to unravel synthetic utility and scalability. Moreover, an isotope labeling reaction was conducted to elucidate a plausible reaction mechanism. 相似文献
92.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(48):15585-15589
π‐Conjugated molecular cages are very challenging targets in structural organic chemistry, supramolecular chemistry, and materials science. The synthesis and physical characterizations are reported of the first three‐dimensionally π‐conjugated diradical molecular cage PTM‐C, in which two polychlorotriphenylmethyl (PTM) radicals are linked by three bis(3,6‐carbazolyl) bridges. This cage compound was synthesized mainly by intermolecular Yamamoto coupling followed by deprotonation and oxidation. It is stable and its structure was confirmed by X‐ray crystallographic analysis. The two carbon‐centered PTM radicals are weakly coupled through electronic interactions with the carbazole spacers, as revealed by optical, electronic, and magnetic measurements as well as theoretical calculations. 相似文献
93.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(45):14405-14409
Coiled‐coil peptides are frequently used to create new function upon the self‐assembly of supramolecular complexes. A multitude of coil peptide sequences provides control over the specificity and stability of coiled‐coil complexes. However, comparably little attention has been paid to the development of methods that allow the reversal of complex formation under non‐denaturing conditions. Herein, we present a reversible two‐state switching system. The process involves two peptide molecules for the formation of a size‐mismatched coiled‐coil duplex and a third, disruptor peptide that targets an overhanging end. A real‐time fluorescence assay revealed that the proximity between two chromophores can be switched on and off, repetitively if desired. Showcasing the advantages provided by non‐denaturing conditions, the method permitted control over the bivalent interactions of the tSH2 domain of Syk kinase with a phosphopeptide ligand. 相似文献
94.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(41):12692-12696
The newly developed oligophenylenevinylene (OPV)‐based fluorescent (FL) chiral chemosensor (OPV‐Me) for the representative enantiomeric guest, 1,2‐cyclohexanedicarboxylic acid (1,2‐CHDA: RR ‐ and SS ‐form) showed the high chiral discrimination ability, resulting in the different aggregation modes of OPV‐Me self‐assembly: RR ‐CHDA directed the fibrous supramolecular aggregate, whereas SS ‐CHDA directed the finite aggregate. The consequent FL intensity toward RR ‐CHDA was up to 30 times larger than that toward SS ‐CHDA. Accordingly, highly enantioselective recognition was achieved. Application to the chirality sensing was also possible: OPV‐Me exhibited a linear relationship between the FL intensity and the enantiomeric excess through the morphological development of stereocomplex aggregates. These results clearly show that the chiral recognition ability is manifested by the amplification cascade of the chirality difference through self‐assembly. 相似文献
95.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(43):13473-13477
Homochirality in peptides is crucial in sustaining “like–like” intermolecular interactions that allow the formation of assemblies and aggregates and is ultimately responsible for the resulting material properties. With the help of a series of stereoisomers of the tripeptide F–F–L, we demonstrate the critical role that peptide stereochemistry plays in the self‐assembly of peptides, guided by molecular recognition, and for self‐sorting. Homochiral self‐assemblies are thermally and mechanically more robust compared to heterochiral self‐assemblies. Morphological studies of the multicomponent peptide systems showed that aggregates formed from homochiral peptides possessed a uniform nano‐fibrous structure, whereas heterochiral systems resulted in self‐sorted systems with a heterogeneous morphology. In essence, homochiral peptides form the stronger aggregates, which may be one of reasons why homochirality is preferred in living systems. 相似文献
96.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(44):13794-13799
Soft and deformable liquid metals (LMs) are building components in various systems related to uncertain and dynamic task environments. Herein we describe the development of a biomolecule‐triggered external‐manipulation method involving LM conjugates for the construction of future innovative soft robotics operating in physiological environments. Functional soft hybrids composed of a liquid‐metal droplet, a thiolated ligand, and proteins were synthesized for the expression of diverse macroscopic commands, such as attachment to cells, binary fusion, and self‐propelled movement through molecular recognition and enzymatic reactions. Our technology could be used to create new state‐of‐the‐art soft robots for chemical and biomedical engineering applications. 相似文献
97.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(39):11955-11958
Singlet oxygen is among the reactive oxygen species (ROS) with the shortest life‐times in aqueous media because of its extremely high reactivity. Therefore, designing sensors for detection of 1O2 is perhaps one of the most challenging tasks in the field of molecular probes. Herein, we report a highly selective and sensitive chemiluminescence probe ( SOCL‐CPP ) for the detection of 1O2 in living cells. The probe reacts with 1O2 to form a dioxetane that spontaneously decomposes under physiological conditions through a chemiexcitation pathway to emit green light with extraordinary intensity. SOCL‐CPP demonstrated promising ability to detect and image intracellular 1O2 produced by a photosensitizer in HeLa cells during photodynamic therapy (PDT) mode of action. Our findings make SOCL‐CPP the most effective known chemiluminescence probe for the detection of 1O2. We anticipate that our chemiluminescence probe for 1O2 imaging would be useful in PDT‐related applications and for monitoring 1O2 endogenously generated by cells in response to different stimuli. 相似文献
98.
Dr. Xin-Ming Hu Magnus H. Rønne Prof. Dr. Steen U. Pedersen Prof. Dr. Troels Skrydstrup Prof. Dr. Kim Daasbjerg 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(23):6568-6572
In a comparative study of the electrocatalytic CO2 reduction, cobalt meso-tetraphenylporphyrin (CoTPP) is used as a model molecular catalyst under both homogeneous and heterogeneous conditions. In the former case, employing N,N-dimethylformamide as solvent, CoTPP performs poorly as an electrocatalyst giving low product selectivity in a slow reaction at a high overpotential. However, upon straightforward immobilization of CoTPP onto carbon nanotubes, a remarkable enhancement of the electrocatalytic abilities is seen with CO2 becoming selectively reduced to CO (>90 %) at a low overpotential in aqueous medium. This effect is ascribed to the particular environment created by the aqueous medium at the catalytic site of the immobilized catalyst that facilitates the adsorption and further reaction of CO2. This work highlights the significance of assessing an immobilized molecular catalyst from more than homogeneous measurements alone. 相似文献
99.