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111.
Click chemistry is employed to couple two β‐cyclodextrins at both ends of azobenzene moiety yielding dumbbell‐shaped amphiphiles (AZO‐β‐CD dimer) constructed by rigid aromatic building blocks as “body”, and hydrophilic cyclodextrins as “head” with almost quantitative yield and purity. Bulk aggregates formed by the self‐assembly of the supraamphiphiles through π–π stacking and hydrophobic effect are observed. Meanwhile, the rationally designed polyesters, named as AZO‐PCL with controllable molecular weights and low polydispersities, are successfully synthesized by ring‐opening polymerization of ε‐caprolactone in the presence of p‐aminoazobenzene as initiator. In the aqueous phase, very stable spherical particles are formed by host–guest interactions between AZO‐β‐CD and AZO‐PCLs; the spherical aggregates inherit the photo‐responsiveness of azobenzene. The detailed aggregation and disaggregation behaviors are fully investigated by TEM, SEM, NMR, 2D NOESY, IR, UV and XRD measurements. Compared to the previous works, our newly developed system can be fabricated with more readily manners, avoiding tedious synthetic process; the reversible and dynamic nature of the non‐covalent interactions also can be modulated alternatively by UV or visible light. Thus, such dumbbell‐shaped supra‐amphiphiles are of great potential applications in the controlled delivery systems. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
112.
113.
Well‐defined cyclic‐polymers (cyclic‐PAzoMMAs), bearing side‐chain phenylazo naphthalene chromophore, were successfully synthesized by the combination of atom transfer radical polymerization (ATRP) and copper(I)‐catalyzed azide/alkyne cycloaddition “click” reaction, as verified by GPC, 1H NMR, FTIR, and MALDI‐TOF mass spectrometry. The cyclic‐PAzoMMA showed higher glass transition temperatures than the linear‐PAzoMMA with the same molecular weight. Interestingly, the cyclic‐PAzoMMA exhibited deeper modulation depth (M.D.) induced by SRG, larger value of the photoinduced birefringence, increased fluorescence emission, and longer fluorescence lifetime in comparison with its linear counterpart.  相似文献   
114.
偶氮苯聚合物薄膜光致表面调制效应研究   总被引:1,自引:1,他引:0  
实验观测了偶氮苯聚合物薄膜在Ar^ 激光(488nm)激发下的光表面调制效应。给出了488nm激光激发条件下,含有不同偶氮苯侧基的聚合物的光表面调制效应的数值。分析比较了偶氮苯聚合物表面调制效应的强弱及其产生的原因。给出光表面调制效应与聚合物接枝率的关系。  相似文献   
115.
设计并合成了一类新型的4′-(4″-n-烷氧基亚苯基乙炔基)4-n-乙氧基偶氮苯及其两个系列的氟代化合物,它们的相变行为通过差示扫描量热法和偏光显微镜进行了测试及观察,发现它们均是液晶化合物,都呈现向列相和近晶相,并且发现该类化合物的相变行为与氟原取代的数目与位置有着密切的关系。相比较不含氟的同类化合物,氟原子的引入降低了化合物的熔点和清亮点,如果两个氟原子对称分布在液晶分子长轴向的两侧有利于向列相的稳定性,相反分布于分子长轴一侧的两个氟原子有利于近晶相的稳定性/。  相似文献   
116.
The association within one molecule ofcalix[4]arene and crown ether moieties leads toligands with new complexing properties. In particular,calix[4]arene bis(crown-6) and some of itsderivatives have been shown to be highly selectiveextractants for caesium ions. This review presents thebackground of the study and the results of crystalstructure determinations and molecular modellingcalculations performed during the investigation of twomolecular families, the bis(crown ether) and theazobenzocrown derivatives of calix[4]arene.  相似文献   
117.
An innovative heterojunction is fabricated between two sides of a freestanding thin film of HCl-doped polyaniline (PANI) derivative containing azobenzene side-chain, which is synthesized through an N-alkyl-substituted reaction. Of the film, the side with being irradiated by UV light during preparation is represented as `A side'; the other side without being irradiated is represented as `N side'. The electrical properties of the heterojunction are measured and the rectifying effect is observed in the {current--voltage} characteristic curves with the values of rectifying ratio (γ) being 20 at ±0.06 V at T= 77K and 4 at ±0.02V at T=300 K separately.  相似文献   
118.
Poly(N‐isopropylacrylamide)‐block‐poly{6‐[4‐(4‐methylphenyl‐azo) phenoxy] hexylacrylate} (PNIPAM‐b‐PAzoM) was synthesized by successive reversible addition‐fragmentation chain transfer (RAFT) polymerization. In H2O/THF mixture, amphiphilic PNIPAM‐b‐PAzoM self‐assembles into giant micro‐vesicles. Upon irradiation of light at 365 nm, fusion of the vesicles was observed directly under an optical microscope. The real‐time fusion process is presented and the derivation is preliminarily due to the perturbation by the photoinduced trans‐to‐cis isomerization of azobenzene units in the vesicles.

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119.
偶氮苯取代乙炔功能化合物的合成与表征   总被引:1,自引:1,他引:0  
采用偶氮偶联和金属钯催化偶联反应法,合成了一系列非线性光学基团直接取代乙炔化合物,其结构经^1HNMR,IR,DSC及元素分析等表征。  相似文献   
120.
赵鹭明  王立军 《光学技术》2001,27(5):427-429
从全息光栅法出发 ,详细阐述了应用偶氮苯聚合物光致表面调制效应制备光栅的新工艺 ,说明使用偶氮苯聚合物薄膜制备光栅方法的特点 ,介绍了采用新工艺制备的光栅的独特性质———光栅可热擦除或光学擦除 ,同时提出应用新材料光栅制造方法所面临的问题。采用新工艺实验制备了薄膜光栅  相似文献   
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