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1.
Synthesis and characterization of double hydrophilic block copolymers containing semi-rigid and flexible segments 下载免费PDF全文
Alice M. Savage Elizabeth Ullrich Stacey M. Chin Zachary Kiernan Caitlyn Kost S. Richard Turner 《Journal of polymer science. Part A, Polymer chemistry》2015,53(2):219-227
3-Methyl-(E)-stilbene (3MSti) and 4-(diethylamino)-(E)-stilbene (DEASti) monomers are synthesized and polymerized separately with maleic anhydride (MAn) in a strictly alternating fashion using reversible addition-fragmentation chain transfer (RAFT) polymerization techniques. The optimal RAFT chain transfer agents (CTAs) for each copolymerization affect the reaction kinetics and CTA compatibilities. Psuedo-first order polymerization kinetics are demonstrated for the synthesis of poly((3-methyl-(E)-stilbene)-alt-maleic anhydride) (3MSti-alt-MAn) with a thiocarbonylthio CTA (methyl 2-(dodecylthiocarbonothioylthio)−2-methylpropionate, TTCMe). In contrast, a dithioester CTA (cumyl dithiobenzoate, CDB) controls the synthesis of poly((4-(diethylamino)-(E)-stilbene)-alt-maleic anhydride) (DEASti-alt-MAn) with pseudo-first order polymerization kinetics. DEASti-alt-MAn is chain extended with 4-acryloylmorpholine (ACMO) to synthesize diblock copolymers and subsequently converted to a double hydrophilic polyampholyte block copolymers (poly((4-(diethylamino)-(E)-stilbene)-alt-maleic acid))-b-acryloylmorpholine) (DEASti-alt-MA)-b-ACMO) via acid hydrolysis. The isoelectric point and dissociation behavior of these maleic acid-containing copolymers are determined using ζ-potential and acid–base titrations, respectively. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 219–227 相似文献
2.
Water‐Soluble Luminescent Hybrid Composites Consisting of Oligosilsesquioxanes and Lanthanide Complexes and their Sensing Ability for Cu2+ 下载免费PDF全文
Qianqian Xu Dr. Zhiqiang Li Prof. Dr. Huanrong Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(9):3037-3043
Water‐soluble hybrid composites with great potential for selective and sensitive sensing and that are obtained through simple, rapid, and environmentally friendly methods are highly desirable and remain a challenging task. Herein, we present luminescent hybrid composites that were realized by linking Na3[Ln(dpa)3] (dpa=2,6‐pyridinedicarboxylic acid) to octa‐amino functionalized polyhedral oligomeric silsesquioxane (POSS‐NH2) through hydrogen‐bonding interactions between the oxygen atoms of the carboxylate groups of dpa and the hydrogen‐bond‐donor amino groups. The resulting hybrid composites Ln(dpa)3@POSS‐NH2 are highly soluble in aqueous solutions and the quantum yield of Eu(dpa)3@POSS‐NH2 is as high as 56.5 % or 46.3 % in the solid state and in aqueous solution, respectively, as determined by using the integrating sphere method. The novel water‐soluble luminescent hybrid composites exhibit high thermal and photostability, and the emitted colors of the resulting hybrid composite can be finely tuned by changing the Eu3+/Tb3+ ratio. Interestingly, Eu(dpa)3@POSS‐NH2 hybrid composites exhibited an effective switch‐off fluorescence response to Cu2+ over other common metal ions in aqueous media. 相似文献
3.
In this work, a phthalonitrile derivative bearing p-sulfonylphenoxy group at the 3-position has been synthesised. The water-soluble non-peripherally tetrasubstituted zinc (3) and cobalt (4) phthalocyanines were obtained by cyclotetramerisation of this phthalonitrile derivative in the presence of anhydrous metal salts by microwave irradiation. The compounds have been characterised by using FT-IR, 1H NMR, UV–Vis and Mass spectrometry (MS) data. The aggregation behaviours of these compounds were investigated in methanol, DMSO, DMF, and water. We have also studied the aggregation behaviours of the phthalocyanine complex 3 in various DMSO/water mixtures. Additionally, the redox properties of the phthalocyanine complexes were examined in dimethylsulfoxide by voltammetry and in situ spectroelectrochemistry. Redox behaviours of the complexes supported the structures of the complexes. Metal and ring-based reductions were observed for 4 and only ring-based electron transfer processes were observed with 3. 相似文献
4.
An uncharged, water-soluble per-ethylene-glycol pillar[5]arene derivative ( 1 ) was synthesized and its aggregation mode, host-guest chemistry in water and extraction ability was explored. Compound 1 is a liquid at room temperature; in water, limited self-aggregation occurred at high concentrations as deduced from diffusion NMR and dynamic light scattering. Compound 1 forms pseudo-rotaxane-like 1 : 1 host-guest complexes with 1,ω-di-substituted alkanes with association constants on the order of 103–104 m −1. Interestingly, NMR experiments showed that the guest location relative to the host ring system differs among the different complexes. In proof-of-concept experiments, compound 1 was shown to extract structurally related organic compounds from benzene into water with significant selectivity. Compound 1 , which is a liquid at room temperature and has only limited interactions with its side arms, can, in principle, be regarded as a complement to or as a kind of type I porous liquid. 相似文献
5.
The influences of pH, contact time, solid-liquid ratio, temperature and C60(C(COOH)2)n on Th(IV) adsorption onto the magnetic multi-walled carbon nanotubes(MMWCNTs) were studied by batch technique. The dynamic process showed that the adsorption of Th(IV) onto MMWCNTs could reach equilibrium in 40 h and matched the pseudo-second-order kinetics model. The adsorption of Th(IV) onto MMWCNTs was significantly dependent on pH values, the adsorption ratio increased markedly at pH 3.0–5.0, and then maintained a steady state as pH values increased. At low pH, different C60(C(COOH)2)n content could enhance the adsorption content of Th(IV) onto MMWCNTs, but restrained it at higher pH. Through simulating the adsorption isotherms by Langmuir, Freundlich and Dubini-Radushkevich models, it could be seen respectively that the adsorption pattern of Th(IV) onto MMWCNTs was mainly surface complexation, and that the adsorption process was endothermic and irreversible. 相似文献
6.
This communication reports the successful adsorption of a water-soluble cationic fluorescent dye Acridine Orange (AO) onto Langmuir–Blodgett (LB) films of a cationic amphiphile octadecylamine (ODA) in the presence of nano-clay platelets hectorite. Acridine orange (AO) has been widely used as a stainer for the characterization of biopolymers. But AO has a tendency to form non-florescent H-dimer even in the aqueous solution. Anionic nano-clay platelets hectorite played an important role in controlling the H-dimer formation of AO in the hybrid film. Effects of various parameters in the adsorption process were investigated in detail. 相似文献
7.
8.
《Journal of Coordination Chemistry》2012,65(7):1115-1126
A UV-Vis spectrophotometric study of adduct formation of SalenH2 (1) and MII(Salen), where M?=?Mn (2), Fe (3), Co (4), Ni (5) and Cu (6) as donors with Me2SnCl2 as acceptor have been investigated in chloroform. Adducts (1a–6a) have been characterized by 1H, 13C and 119Sn NMR, IR and electronic spectroscopy and microanalysis. Formation constants and thermodynamic parameters were measured for 1 : 1 and 2 : 1 adducts at various temperatures (T?=?278 to 308 K). The data refinement was carried out with the SQUAD 84 program. The trend of formation constants of MII(Salen) complexes with Me2SnCl2 follows the order: Mn>Fe>Cu>Co>Ni. The formation constants for the free 1 and MII(Salen) with Me2SnCl2 changes according to the following trend: MII(Salen)>SalenH2 相似文献
9.
AbstractTwo new lignans mubezhisol (1) and mubezhisal (2), together with twenty six known compounds (3–28) were isolated from water-soluble fraction from the semens of Momordica cochinchinensis. In the subsequent action evaluation, four saponins (4, 6, 13, 27), six lignans (1, 2, 16, 17, 22, 23), and one naphthoquinone (24) exhibited the significant cytotoxicity. The results indicated that various saponins and lignans were mainly responsible for the antitumor activities of Momordicae Semen. 相似文献
10.