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991.
Jinwei Sun Xinrui Yang Yun Liu Yi Wang Yi Pan 《Journal of heterocyclic chemistry》2020,57(3):1449-1455
An efficient synthesis of 3-nitroimidazo[1,2-a]pyridines has been developed via N-iodosuccinimide (NIS)-mediated multicomponents reaction of 2-aminopyridines, aldehydes, and nitromethane under metal-free conditions. This protocol has many advantages such as broad substituent scope, mild and eco-friendly conditions, high step economy, and good yields. 相似文献
992.
Shuai Yang Kaijie Xu Qiuqin Lai Chen Zhao Hanhong Xu 《Journal of heterocyclic chemistry》2020,57(12):4304-4311
In searching for novel insecticidal leads, a series of N-pyridylpyrazolo-5-methyl amines and their derivatives were designed and synthesized. Among the 22 target compounds obtained, bioassays indicated that some of the target compounds exhibited good insecticidal activities against Plutella xylostella (P. xylostella) and Spodoptera frugiperda (S. frugiperda). In particular, compound 9j revealed the best insecticidal activity against P. xylostella, with a LC50 value of 22.11 mg/L, and compound 9q had the best insecticidal activity against S. frugiperda which with 73.99% of mortality rate at 100 mg/L. Structure-activity relationship (SAR) analysis showed that 4-CF3 at the position of R1 linked with N-pyridylpyrazole via amide bond could enhance the insecticidal activity of the target compounds. This study provides valuable clues for the further design and optimization of N-pyridylpyrazole derivatives. 相似文献
993.
A series of new ligands L1-L7 were readily prepared in one step.Friedel-Crafts alkylation of indoles with nitroalkenes catalyzed by a novel Cu(Ⅱ)-L complex has been developed.The remarkable advantages of this reaction are mild reaction conditions,simple workup procedure,high yields of products and the use of ethanol as a green solvent. 相似文献
994.
A novel and efficient synthetic method of atorvastatin was described.The key step of the synthesis was the construction of the olefin linkage between the chiral side chain and skeleton via a Horner-Wadsworth-Emmons reaction,resulting in the advanced intermediate of atorvastatin under hydrogenation of the olefin over Pd/C.This novel method is more useful for the practical synthesis of atorvastatin than its document reported methods. 相似文献
995.
Yuedi Ding Jun Fan Wenxin Li Runlin Yang Ying Peng Lili Deng Yu Wu Qiang Fu 《Applied biochemistry and biotechnology》2013,170(7):1637-1648
Somatostatin is a natural inhibitor of growth hormone, and its analogues are clinically used for the therapy of acromegaly, gigantism, thyrotropinoma, and other carcinoid syndrome. However, natural somatostatin is limited for clinical usage because of its short half-life in vivo. Albumin fusion technology was used to construct long-acting fusion proteins, and Pichia pastoris was used as an expression system. Three fusion proteins, (somatostatin (SS)14)2-human serum albumin (HSA), (SS14)3-HSA, and HSA-(SS14)3, were constructed with different fusion copies of somatostatin-14 and fusion orientations. The expression level of (SS14)3-HSA and HSA-(SS14)3 was much lower than (SS14)2-HSA due to the additional fusion of the somatostatin-14 molecule. Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry revealed that severe degradation occurred in the fermentation process. Similar to the standard of somatostatin-14, all three fusion proteins were able to inhibit growth hormone secretion in the blood, with (SS14)2-HSA being the most effective one. On the whole, (SS14)2-HSA was the most effective protein in both production level and bioactivity, and increasing the number of small protein copies fused to HSA may not be a suitable method to improve the protein bioactivity. 相似文献
996.
Hai Y Chen JJ Zhao P Lv H Yu Y Xu P Zhang JL 《Chemical communications (Cambridge, England)》2011,47(8):2435-2437
A novel class of ZnSalens (ZnL(1-10)) with lipophilic and cationic conjugates as optical probes in single and two-photon fluorescence microscopy images of living cells were prepared, which exhibited chemo- and photostability, low cytotoxicity and high subcellular selectivity. 相似文献
997.
He C Qian X Xu Y Yang C Yin L Zhu W 《Dalton transactions (Cambridge, England : 2003)》2011,40(5):1034-1037
A novel ratiometric fluorescent probe for oxalic acid was designed and synthesized, based on the zinc-containing [DAQZ@2Zn(2+)] complex. It shows highly selective "on-off" fluorescence changes with a more than 20 nm blue shift in wavelength for oxalic acids in aqueous solution. Moreover, it can fluorescently respond to oxalic acid in living cells. 相似文献
998.
A facile one-pot method to high-quality Ag-graphene composite nanosheets for efficient surface-enhanced Raman scattering 总被引:2,自引:0,他引:2
Zhang Z Xu F Yang W Guo M Wang X Zhang B Tang J 《Chemical communications (Cambridge, England)》2011,47(22):6440-6442
Ag-graphene composite nanosheets (AGCN) with adjustable size and well-controlled densities of Ag nanoparticles (Ag NPs) using Poly(N-vinyl-2-pyrrolidone) (PVP) as a reductant and stabilizer are reported. The obtained AGCN substrate is extremely suitable for surface-enhanced Raman spectroscopy (SERS). 相似文献
999.
An efficient synthetic method has been developed for the synthesis of 2-arylacrylic esters from the corresponding aryl methyl ketones via Wittig reaction and singlet oxygen ene reaction. Wittig reaction to aryl methyl ketones with (methoxymethyl)triphenylphosphonium chloride in basic condition afforded the methyl enol ethers, and then 2-arylacrylic esters were obtained by singlet oxygen ene reaction, followed by tosylation and elimination in one-pot to the methyl enol ethers in good yields. 相似文献
1000.
Liu M Gan M Lin S Zhang Y Zi J Song W Fan X Liu Y Yang Y Shi J 《Organic letters》2011,13(11):2856-2859
Two structurally novel homocucurbitane triterpenoid glycosides, machilusides A (1) and B (2), possessing an unprecedented C(36) skeleton with a D-fructose moiety incorporated into a cucurbitane nucleus forming unique cage-like tricyclic ring moieties, were isolated from the stem bark of Machilus yaoshansis. Their structures were determined by spectroscopic methods. Both compounds exhibited nonselective cytotoxic activities against several human cancer cell lines. The biosynthetic pathway of 1 and 2 was postulated. 相似文献