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991.
Significant attention has been focused on bone tumor therapy recently. At present, the treatment in clinic typically requires surgical intervention. However, a few tumor cells remain around bone defects after surgery and subsequently proliferate within several days. Thus, fabrication of biomaterials with dual functions of tumor therapy and bone regeneration is significant. Herein, the injectable hydrogel containing cisplatin (DDP) and polydopamine‐decorated nano‐hydroxyapatite is prepared via Schiff base reaction between the aldehyde groups on oxidized sodium alginate and amino groups on chitosan. The hydrogel exhibits sustained release properties for DDP due to the immobilization of DDP via abundant functional groups on polydopamine (PDA). Additionally, given the intense absorption of PDA in the near‐infrared region, the hydrogel exhibits excellent photothermal effects when exposed to the NIR laser (808 nm). Based on the properties, the hydrogel effectively ablates tumor cells (4T1 cells) in vitro and suppresses tumor growth in vivo. Furthermore, the hydrogel promotes the adhesion and proliferation of bone mesenchymal stem cells in vitro due to the abundant functional groups on PDA and further induces bone regeneration in vivo. Therefore, the study extends research on novel biomaterials with dual functions of tumor therapy and bone regeneration.  相似文献   
992.
Zhang  De  Liang  Pei  Ye  Jiaming  Xia  Jing  Zhou  Yongfeng  Huang  Jie  Ni  Dejiang  Tang  Lisha  Jin  Shangzhong  Yu  Zhi 《Analytical and bioanalytical chemistry》2019,411(27):7187-7196
Analytical and Bioanalytical Chemistry - Surface-enhanced Raman spectroscopy (SERS) has the potential to detect pesticide residues in agricultural products. However, some systemic pesticides, such...  相似文献   
993.
Zhou  Yabin  Hua  Jin  Tang  Ben Zhong  Tang  Youhong 《中国科学:化学(英文版)》2019,62(10):1312-1332
Fluorescence imaging is an important branch of bioimaging. It is non-invasive and provides superior spatial and temporal resolution during the real-time monitoring of biological samples of interest. Although the spatial resolution limit of optical microscopes is about 200 nm, due to the diffraction limit, with the application of super-resolution fluorescence microscopy technologies this limit has been pushed below 30 nm. This makes it feasible to visualize biological structures in subcellular levels and to monitor subcellular biological processes in real time. However, due to the complexity of the biological structure and components within cells, simultaneous staining and monitoring multiple intracellular components with different coloured fluorophores is often needed during multiplex imaging, to better understand biological processes. Aggregation-induced emission luminogens(AIEgen) and AIEgen based nanoparticles(NPs) have presented many advantages in fluorescence imaging, with strong potential for biological science and nano-medicine. Herein this review, we focus on the advantages of AIEgen and AIEgen NP in cell-based fluorescence imaging, and the latest advances of AIEgens in cell-based multiplex imaging are summarized and discussed. The future perspectives are proposed.  相似文献   
994.
Cao  Jing  Wu  Binghui  Peng  Jian  Feng  Xiaoxia  Li  Congping  Tang  Yu 《中国科学:化学(英文版)》2019,62(3):363-369
A CuI coated Cu hybrid nanostructure by partial iodation of Cu nanowires was used as hole transport material(HTM) to enhance the charge transfer in inverted perovskite solar cells(PSCs). The outer CuI achieved efficient charge extraction, and the inner copper facilitated the extracted charges to be rapidly transferred, further improving the overall cell performance. Furthermore,we employed a mixture of [6,6]-phenyl-C71-butyric acid methyl ester(PCBM) and ZnO nanoparticles as electron transport material(ETM) to achieve the fabrication of stable PSCs. The best efficiency was up to 18.8%. This work represents a fundamental clue for the design of efficient and stable PSCs using the chemical in-situ construction strategy for HTM and integration of PCBM and ZnO as ETM.  相似文献   
995.
Hu  Rong  Chen  Xu  Zhou  Taotao  Si  Han  He  Benzhao  Kwok  Ryan T. K.  Qin  Anjun  Tang  Ben Zhong 《中国科学:化学(英文版)》2019,62(9):1198-1203
Unnatural reaction in the living cells is a powerful tool for biological research. However, the polymerization inside cells is rarely reported. In this work, a lab-in-cell is illustrated based on our developed spontaneous amino-yne click polymerization. Carbonyl group activated terminal diyne can spontaneously polymerize with tetraphenylethene(TPE)-containing primary diamine inside cells, and polymer with weight-average molecular weight of 7,300 was yielded. By utilizing this in vivo amino-yne click polymerization and taking advantage of the aggregation-induced emission feature of TPE, a "turn-on" cell imaging was realized,and in-situ killing of cells was also acquired by destroying the structures of actin and tubulin, which cannot be realized by preprepared polymer. This strategy provides a useful platform and holds great promise in biochemistry and therapy applications.  相似文献   
996.
In this work, we aim to develop cancer cell‐targeting AIE dots based on a polyyne‐bridged red‐emissive AIEgen, 2TPE‐4E, through the combination of metabolic engineering and bio‐orthogonal reactions. Azide groups on a tumor were efficiently produced by intravenous injection of Ac4ManNAz and glycol‐metabolic engineering. These bio‐orthogonal azide groups could facilitate the specific targeting of DBCO‐AIE dots to the tumor cells undergoing metal‐free click reaction in vivo. The efficiency of this targeting strategy could be further improved with the development of new bio‐orthogonal chemical groups with higher reactivity and a large amount of AIEgens could be delivered to the tumor for diagnosis.  相似文献   
997.
Molecular ferroelectrics have displayed a promising future since they are light‐weight, flexible, environmentally friendly and easily synthesized, compared to traditional inorganic ferroelectrics. However, how to precisely design a molecular ferroelectric from a non‐ferroelectric phase transition molecular system is still a great challenge. Here we designed and constructed a molecular ferroelectric by double regulation of the anion and cation in a simple crown ether clathrate, 4 , [K(18‐crown‐6)]+[PF6]?. By replacing K+ and PF6? with H3O+ and [FeCl4]? respectively, we obtained a new molecular ferroelectric [H3O(18‐crown‐6)]+[FeCl4]?, 1 . Compound 1 undergoes a para‐ferroelectric phase transition near 350 K with symmetry change from P21/n to the Pmc21 space group. X‐ray single‐crystal diffraction analysis suggests that the phase transition was mainly triggered by the displacement motion of H3O+ and [FeCl4]? ions and twist motion of 18‐crown‐6 molecule. Strikingly, compound 1 shows high a Curie temperature (350 K), ultra‐strong second harmonic generation signals (nearly 8 times of KDP), remarkable dielectric switching effect and large spontaneous polarization. We believe that this research will pave the way to design and build high‐quality molecular ferroelectrics as well as their application in smart materials.  相似文献   
998.
Ivabradine hydrochloride (IVA‐HCl) (systematic name: {[3,4‐dimethoxybicyclo[4.2.0]octa‐1(6),2,4‐trien‐7‐yl]methyl}[3‐(7,8‐dimethoxy‐2‐oxo‐2,3,4,5‐tetrahydro‐1H‐3‐benzazepin‐3‐yl)propyl]methylazanium), is a novel medication used for the symptomatic management of stable angina pectoris. In many recent patents, it has been claimed to exist in a very large number of polymorphic, hydrated and solvated phases, although no detailed analysis of the structural features of these forms has been published to date. Here, we have successfully crystallized the tetrahydrate form of IVA‐HCl (form β), C27H37N2O5+·Cl?·4H2O, and elucidated its structure for the first time. Simultaneously, a new crystal form of IVA‐HCl, i.e. the hemihydrate (form II), C27H37N2O5+·Cl?·0.5H2O, was discovered. Its crystal structure was also accurately determined and compared to that of the tetrahydrate form. While the tetrahydrate form of IVA‐HCl crystallized in the orthorhombic space group P212121, the new form (hemihydrate) was solved in the monoclinic space group P21. Detailed conformational and packing comparisons between the two forms have allowed us to understand the role of water in the crystal assembly of this hydrochloride salt. The stabilities of the two forms were compared theoretically by calculating the binding energy of the water in the crystal lattice using differential scanning calorimetry (DSC). The stability experiments show that the tetrahydrate is stable under high‐humidity conditions, while the hemihydrate is stable under high‐temperature conditions.  相似文献   
999.
Two new three‐dimensional (3D) LnIII metal‐organic frameworks (MOFs) were designed and successfully obtained via a solvothermal reaction between lanthanide(III) nitrates and a semi‐flexible carbazole tetracarboxylate acid linker as a high‐performance chromophore. 1 and 2 possess porous 3D networks with channels along the a axis, and more importantly, they show a highly sensitive and selective fluorescence quenching response to Fe3+ and CrVI anions. The sensing mechanism investigation revealed that the weak interactions of Fe3+ with nitrogen atoms of carbazole and deprotonated carboxylic acids protruding into the pores of MOFs quenched the luminescence of 1 and 2 effectively. In addition, the competition absorption also played an important role in the luminescence quenching detection of Fe3+ based on 1 , and CrVI anions based on 1 and 2 . Therefore, 1 and 2 represent an alternative example of regenerable luminescence based sensors for the quantitative detection of Fe3+ and CrVI anions.  相似文献   
1000.

Classical Bose-Chaudhuri-Hocquenghem (BCH) codes over finite fields have been studied extensively. The Calderbank-Shor-Steane (CSS) construction, especially Steane’s enlargement, and Hermitian construction are the most widely used methods in design of quantum codes. The BCH codes containing their Euclidean dual or Hermitian dual codes can be used to generate good stabilizer codes. Therefore, we can construct quantum codes by classical BCH codes over finite fields in this paper. Firstly, we study the properties of such classical BCH codes in terms of the cyclotomic cosets. It is convenient to compute the dimension of new quantum BCH codes. Meanwhile, it ensures that classical BCH codes are Euclidean dual-containing or Hermitian dual-containing. These results about suitable cyclotomic cosets make it possible to construct several new families of nonbinary quantum BCH codes with a given parameter set. Compared with the ones available in the literature, the quantum BCH codes in our schemes have good parameters. In particular, we extend to more general cases than known results.

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