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41.
We described the design and synthesis of a colorimetric and ratiometric fluorescent probe based on a conjugated π-electron system that displayed differential fluorescence responses towards cyanide and sulfide and demonstrated its utility in intracellular ion imaging and logic gate. 相似文献
42.
Amino acids are firstly employed in transition-metal free heterocyclization reaction of 1,3-diynes in the presence of K3PO4 and DMSO at 120 °C. This method produces 2,3,6-trisubstituted pyridines with up to 86% yield. The –CO2H group on the amino acids is crucial for this heterocyclization reaction. The mechanism of such a heterocyclization reaction is discussed, as well. 相似文献
43.
He Yanfang Niu Xiangheng Shi Libo Zhao Hongli Li Xin Zhang Wenchi Pan Jianming Zhang Xifeng Yan Yongsheng Lan Minbo 《Mikrochimica acta》2017,184(7):2181-2189
Microchimica Acta - The authors describe a photometric method for the determination of free cholesterol based on the oxidation of cholesterol by the catalytic action of the enzyme... 相似文献
44.
Shuai Zhang Zhi-Wei Zhao Zhen-Dong Fang Jie Liu 《Russian Journal of Applied Chemistry》2017,90(3):458-466
The effect of combined filtration efficiency on the performance of anthracite filtration?micro electrolysis?sand filtration (AMS) was investigated. Impact of different operating parameters, such as iron?carbon ratio of micro electrolytic units, filtration velocity of AMS, were studied. It was found that when iron?carbon ratio was 6: 4, the AMS’s average turbidity removal rate was 96.75% at the filtration velocity of 3 m h?1. The results showed that when the filtration rate was 3?9 m h?1 and iron?carbon ratio was 6: 4, the turbidity removal efficiency was over 94%, and the turbidity of the effluent was less than 1 NTU in effective filtration cycle. The effective filtration cycle can last for more than 5 h or longer. Meanwhile, the removal rate of UV254 was above 33%, and the concentration of iron ions in the effluent is less than 0.15 mg L?1. Turbidity and iron indicators have reached the national drinking water standards. It was also found the mechanism of iron?carbon micro electrolytic enhanced filtration by infrared spectroscopy and scanning electron microscopy. And It was also speculated the reasons for the reaction passivation. 相似文献
45.
46.
Vizing conjectured that every edge chromatic critical graph contains a 2-factor. Believing that stronger properties hold for this class of graphs, Luo and Zhao (2013) showed that every edge chromatic critical graph of order with maximum degree at least is Hamiltonian. Furthermore, Luo et al. (2016) proved that every edge chromatic critical graph of order with maximum degree at least is Hamiltonian. In this paper, we prove that every edge chromatic critical graph of order with maximum degree at least is Hamiltonian. Our approach is inspired by the recent development of Kierstead path and Tashkinov tree techniques for multigraphs. 相似文献
47.
An arc of a digraph is called universal if and are in a common cycle for any vertex of . In this paper we characterize local tournaments whose every arc is universal. 相似文献
48.
Nan Zhao Huawei Mou Yuguang Zhou Xinxin Ju Shoujun Yang Shan Liu Renjie Dong 《Molecules (Basel, Switzerland)》2021,26(4)
Developing a green and sustainable method to upgrade biogas wastes into high value-added products is attracting more and more public attention. The application of solid residues as a performance enhancer in the manufacture of biofilms is a prospective way to replace conventional plastic based on fossil fuel. In this work, solid digestates from the anaerobic digestion of agricultural wastes, such as straw, cattle and chicken manures, were pretreated by an ultrasonic thermo-alkaline treatment to remove the nonfunctional compositions and then incorporated in plasticized starch paste to prepare mulching biofilms by the solution casting method. The results indicated that solid digestate particles dispersed homogenously in the starch matrix and gradually aggregated under the action of a hydrogen bond, leading to a transformation of the composites to a high crystalline structure. Consequently, the composite biofilm showed a higher tensile strength, elastic modulus, glass transition temperature and degradation temperature compared to the pure starch-based film. The light, water and GHG (greenhouse gas) barrier properties of the biofilm were also reinforced by the addition of solid digestates, performing well in sustaining the soil quality and minimizing N2O or CH4 emissions. As such, recycling solid digestates into a biodegradable plastic substitute not only creates a new business opportunity by producing high-performance biofilms but also reduces the environmental risk caused by biogas waste and plastics pollution. 相似文献
49.
Ning Liang Yuk-Man Li Zouyan He Wangjun Hao Yimin Zhao Jianhui Liu Hanyue Zhu Erika Kwek Ka-Ying Ma Wen-Sen He Zhen-Yu Chen 《Molecules (Basel, Switzerland)》2021,26(12)
Rutin (R) and quercetin (Q) are two widespread dietary flavonoids. Previous studies regarding the plasma cholesterol-lowering activity of R and Q generated inconsistent results. The present study was therefore carried out to investigate the effects of R and Q on cholesterol metabolism in both HepG2 cells and hypercholesterolemia hamsters. Results from HepG2 cell experiments demonstrate that both R and Q decreased cholesterol at doses of 5 and 10 µM. R and Q up-regulated both the mRNA and protein expression of sterol regulatory element binding protein 2 (SREBP2), low-density lipoprotein receptor (LDLR), and liver X receptor alpha (LXRα). The immunofluorescence study revealed that R and Q increased the LDLR expression, while only Q improved LDL-C uptake in HepG2 cells. Results from hypercholesterolemia hamsters fed diets containing R (5.5 g/kg diet) and Q (2.5 g/kg diet) for 8 weeks demonstrate that both R and Q had no effect on plasma total cholesterol. In the liver, only Q reduced cholesterol significantly. The discrepancy between the in vitro and in vivo studies was probably due to a poor bioavailability of flavonoids in the intestine. It was therefore concluded that R and Q were effective in reducing cholesterol in HepG2 cells in vitro, whereas in vivo, the oral administration of the two flavonoids had little effect on plasma cholesterol in hamsters. 相似文献
50.
Wang Danbo Guo Guangming Chen Renzeng Gong Yuzhen Sun Lishui Zhao Yingjie 《中国科学:化学(英文版)》2021,64(9):1510-1514
Two charge-transfer single crystals induced by donor-acceptor interactions were obtained. The presence of different solvent molecules led to 1D(linear) or 2D self-assembly modes. More interestingly, the 2 D organic framework, a layer-by-layer 2D organic framework single crystal, showed a stronger charge-transfer effect than the 1D cocrystal. 相似文献