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Tobias G. Brevé Mike Filius Sven Weerdenburg Stefan J. van der Griend Tim P. Groeneveld Dr. Antonia G. Denkova Dr. Rienk Eelkema 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(10):e202103523
Stimuli-responsive soft materials enable controlled release of loaded drug molecules and biomolecules. Controlled release of potent chemotherapeutic or immunotherapeutic agents is crucial to reduce unwanted side effects. In an effort to develop controlled release strategies that can be triggered by using Cerenkov luminescence, we have developed polymer hydrogels that can release bovine serum albumin and immunoglobulin G by using light (254 nm–375 nm) as a trigger. We describe the synthesis and photochemical characterization of two light sensitive phenacyl bis-azide crosslinkers that are used to prepare transparent self-supporting hydrogel patches. One crosslinker was designed to optimize the overlap with the Cerenkov luminescence emission window, bearing an π-extended phenacyl core, resulting in a high quantum yield (14 %) of photocleavage when irradiated with 375 nm light. We used the extended phenacyl crosslinker for the preparation of protein-loaded dextran hydrogel patches, which showed efficient and selective dosed release of bovine serum albumin or immunoglobulin G after irradiation with 375 nm light. Cerenkov-triggered release is as yet inconclusive due to unexpected side-reactivity. Based on the high quantum yield, efficient release and large overlap with the Cerenkov window, we envision application of these photosensitive soft materials in radiation targeted drug release. 相似文献
76.
Oleg N. Tretinnikov Natalya I. Sushko Anastasia V. Protosovskaya Artsiom V. Radkevich Eryk I. Pavalanski 《先进技术聚合物》2022,33(1):254-259
Radiochromic films composed of polymer matrices and organic dyes are widely used for routine dosimetry purposes in operation of various radiation facilities—gamma and X-ray-irradiation, electron accelerators, and so on. However, the sensitivity of these films rapidly decreases at doses exceeding 30–50 kGy due to a saturation of their optical response, making them unsuitable for accurate dosimetry in radiation processing of polymers and composites where doses up to 200 kGy are typically employed. To overcome this limitation, the use of inorganic substances as the coloring agents of polymer-based radiochromic films was proposed in this paper, specifically, heteropolyacidacid H3PW12O40 (tungstophosphoric acid) in the matrix of poly(vinyl alcohol) (PVA). Nanocomposite PVA/H3PW12O40 films were prepared by solution casting and their optical responses toward 60Co gamma radiation and beams of 6 MeV electrons for a dose range of 10–200 kGy were investigated. It was established that upon exposure to gamma rays and electron beams, the films turn blue and a broad absorption band at 750 nm appears in their spectra. Importantly, the radiation-induced optical absorption increases in a linear fashion up to the dose of 150 kGy and only slightly deviates from linearity at 200 kGy. Moreover, it was found that the PVA/H3PW12O40 films have a long shelf life, are dose-rate independent within a wide range, and color-stable after irradiation. All these features make the nanocomposite PVA/H3PW12O40 films promising for use as routine dosimeters and dose labels in a much wider range of high doses as compared to radiochromic films based on organic dyes. 相似文献
77.
Most recent advances in the synthesis of supramolecular hydrogels based on low molecular weight gelators (LMWGs) have focused on the development of novel hybrid hydrogels, combining LMWGs and different additives. The dynamic nature of the noncovalent interactions of supramolecular hydrogels, together with the specific properties of the additives included in the formulation, allow these novel hybrid hydrogels to present interesting features, such as stimuli-responsiveness, gel-sol reversibility, self-healing and thixotropy, which make them very appealing for multiple biomedical and biotechnological applications. In particular, the inclusion of magnetic nanoparticles in the hydrogel matrix results in magnetic hydrogels, a particular type of stimuli-responsive materials that respond to applied magnetic fields. This review focuses on the recent advances in the development of magnetic supramolecular hydrogels, with special emphasis in the role of the magnetic nanoparticles in the self-assembly process, as well as in the exciting applications of these materials. 相似文献
78.
Ryohei Yoshisaki Dr. Shinya Kimura Dr. Masashi Yokoya Prof. Dr. Masamichi Yamanaka 《化学:亚洲杂志》2021,16(14):1937-1941
Maltose is a ubiquitous disaccharide produced by the hydrolysis of starch. Amphiphilic ureas bearing hydrophilic maltose moiety were synthesized via the following three steps: I) construction of urea derivatives by the condensation of 4-nitrophenyl isocyanate and alkylamines, II) reduction of the nitro group by hydrogenation, and III) an aminoglycosylation reaction of the amino group and the unprotected maltose. These amphiphilic ureas functioned as low molecular weight hydrogelators, and the mixtures of the amphipathic ureas and water formed supramolecular hydrogels. The gelation ability largely depended on the chain length of the alkyl group of the amphiphilic urea; amphipathic urea having a decyl group had the highest gelation ability (minimum gelation concentration=0.4 mM). The physical properties of the supramolecular hydrogels were evaluated by measuring their thermal stability and dynamic viscoelasticity. These supramolecular hydrogels underwent gel-to-sol phase transition upon the addition of α-glucosidase as a result of the α-glucosidase-catalyzed hydrolysis of the maltose moiety of the amphipathic urea. 相似文献
79.
Yuping Wang Attalla F. El-Kott Ayman E. El-Kenawy Liangjun Xue 《Arabian Journal of Chemistry》2021,14(7):103201
In this study, a green protocol for supporting CuO nanoparticles over chitosan-modified amino-magnetic nanoparticles is described. The physicochemical and morphological properties of the desired nanocomposite assessed by various techniques like ICP, FT-IR, FE-SEM, EDX, TEM, XRD and VSM. In the oncological part of the recent study, the Cu(NO3)2, Fe3O4, and Fe3O4-NH2@CS/CuO nanocomposite cell viability was very low against human gastric cancer cell lines i.e. MKN45, AGS, and KATO III and human colorectal carcinoma cell lines i.e. HT-29, HCT 116, HCT-8 [HRT-18], and Ramos.2G6.4C10. The IC50 of Fe3O4-NH2@CS/CuO nanocomposite against MKN45, AGS, KATO III, HT-29, HCT 116, HCT-8 [HRT-18], and Ramos.2G6.4C10 cell lines were 517, 525, 544, 282, 214, 420, and 477 µg/mL, respectively. Thereby, the best anti-gastro-duodenal cancers findings of our Fe3O4-NH2@CS/CuO nanocomposite was seen in the HCT 116 cell line case. 相似文献
80.
Khaled D. Khalil Sayed M. Riyadh Mariusz Jaremko Thoraya A. Farghaly Mohamed Hagar 《Molecules (Basel, Switzerland)》2021,26(12)
Recently, the development of nanocatalysts based on naturally occurring polysaccharides has received a lot of attention. Chitosan (CS), as a biodegradable and biocompatible polysaccharide, is considered to be an excellent template for the design of a hybrid biopolymer-based metal oxide nanocomposite. In this case, lanthanum oxide nanoparticles doped with chitosan at different weight percentages (5, 10, 15, and 20 wt% CS/La2O3) were prepared via a simple solution casting method. The prepared CS/La2O3 nanocomposite solutions were cast in a Petri dish in order to produce the developed catalyst, which was shaped as a thin film. The structural features of the hybrid nanocomposite film were studied by FTIR, SEM, and XRD analytical tools. FTIR spectra confirmed the presence of the major characteristic peaks of chitosan, which were modified by interaction with La2O3 nanoparticles. Additionally, SEM graphs showed dramatic morphological changes on the surface of chitosan, which is attributed to surface adsorption with La2O3 molecules. The prepared CS/La2O3 nanocomposite film (15% by weight) was investigated as an effective, recyclable, and heterogeneous base catalyst in the synthesis of pyridines and pyrazoles. The nanocomposite used was sufficiently stable and was collected and reused more than three times without loss of catalytic activity. 相似文献