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991.
2‐Phenyl‐1,1,3‐tricyano‐3‐bromopropene 1 reacts with the aromatic amines 2a–f and 6a–c to afford the N‐substituted pyrroles 4a–d, the pyrrolo[1,2‐a]quinazoline derivatives 5a, b, and the diaza‐as‐indacene derivatives 7a–c and 8a–c, presumably via elimination of hydrogen bromide followed by cyclization of the formed acyclic intermediates. All structures are confirmed by analytical and spectral data. 相似文献
992.
Treatment of a novel polymer‐supported phenylselenomethyltrimethylsilane reagent with LDA followed by alkylation and oxidative deselenation efficiently afforded aliphatic aldehydes in moderate to good yields with excellent purities. 相似文献
993.
Indium chloride was found to be a very efficient catalyst for the synthesis of amidoalkyl naphthols from β-naphthol, aromatic aldehydes, and acetamide/urea under solvent-free conditions using microwave irradiation. 相似文献
994.
An efficient and convenient method for the preparation of 2,4-diamino-6-arylpyrimidine-5-carbonitrile derivatives by the one-pot reaction of aromatic aldehydes, malononitrile, and guanidine carbonate, in the presence of sodium hydroxide under solvent-free conditions, was reported. This method has the advantages of excellent yields, mild reaction conditions, easy work up, and environmental friendliness over the existing procedures. 相似文献
995.
Mukka Satish Kumar Marri Venkateswarlu Purugula Venkanna Pondichery Kuppuswamy Saiprakash 《合成通讯》2013,43(19):2251-2258
An efficient and safe method for nitration of aromatic compounds and decarboxylative nitration of α,β-unsaturated acids was developed using trichloroisocyanuric acid (TCICA)/dimethylformamide (DMF) in the presence of NaNO2. The reaction times of conventional protocol reduced from 8–10 h to 1.0–1.5 h (60–90 min) under sonication, even though the yields are comparable under both the conditions. 相似文献
996.
Zhenhua Shang 《合成通讯》2013,43(20):2927-2937
Aromatic aldehyde N‐acylhydrazones were oxidized into 2,5‐disubstituted 1,3,4‐oxadiazoles with bis(trifluoroacetoxy)iodobenzene in CHCl3 or DMSO at room temperature in good to excellent yields. 相似文献
997.
A simple and efficient Knoevenagel condensation method for the synthesis of trisubstituted electrophilic alkenes was developed using lipase as a biocatalyst. Knoevenagel condensation was performed using the conventional method and using lipases (Aspergillus oryzae or Rhizopus oryzae) as biocatalysts, and reaction time, reaction temperature, yield, and recyclability were compared. Using a lipase as a biocatalyst eliminated the need for bases such as piperidine and pyridine. A wide range of aromatic aldehydes and ketones readily undergo condensation with active methylene compounds. The workup procedure is also very simple, and yields of the reactions are in the range of 75% to 95%. Both the biocatalysts were effectively recycled four times with no major decrease in the yield of product. The remarkable catalytic activity and reusability of lipase widens its applicability in Knoevenagel condensation with good to excellent yields for synthesis of trisubstituted electrophilic alkenes. 相似文献
998.
Santosh V. Goswami Prashant. B. Thorat Vijay N. Kadam Sachin A. Khiste Sudhakar R. Bhusare 《中国化学快报》2013,24(5):422-424
An efficient protocol was developed for the synthesis of 3-aminoalkylated indoles using 3-chlorophenylboronic acid as a catalyst under ambient temperature conditions. The three-component reaction of indoles, aromatic aldehydes and N-methyl aniline offered corresponding 3-aminoalkylated indoles in excellent yields. This protocol presents some remarkable features such as mild reaction conditions, simple workup procedure and excellent yields. 相似文献
999.
Mohammad Reza Islami Elaheh Mosaddegh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):3134-3138
An efficient method for the synthesis of 4H-benzo[b]pyrans has been developed by the use of Ce(SO4)2·4H2O (2.5 mol%) as a catalyst. Heating the mixture of an appropriate aldehyde, malononitrile, and dimedone in the presence of the catalyst at 45°C in a mixture of water:ethanol (1:1) as solvent for about 9–55 min resulted excellent yields of the corresponding products. Short experimental time of the reaction, excellent yields, simple workup, not using cumbersome apparatus for purification of the products, and inexpensiveness and commercially availability of the catalyst are the advantages of this method. 相似文献
1000.
Rashid Badri Maryam Gorjizadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):544-549
An efficient and convenient synthesis of 1,3,4-oxadiazoles from aromatic aldehydes, acyl hydrazide, and 1,4- bis(triphenylphosphonium)-2-butene peroxodisulfate is reported. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献