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91.
Dr. Thierry Achard Julien Egly Michel Sigrist Dr. Aline Maisse-François Dr. Stéphane Bellemin-Laponnaz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(58):13271-13274
A dehydrogenation of primary amine to give the corresponding nitrile under oxidant- and base-free conditions catalysed by simple [Ru(p-cym)Cl2]2 with no extra ligand is reported. The system is highly selective for alkyl amines, whereas benzylamine derivatives gave the nitrile product together with the imine in a ratio ranging from 14:1 to 4:1 depending on the substrate. Preliminary mechanistic investigations have been performed to identify the key factors that govern the selectivity. 相似文献
92.
DRAB David M. KELLEY Steven P. SHAMSHINA Julia L. SMIGLAK Marcin COJOCARU O. Andreea GURAU Gabriela ROGERS Robin D. 《中国科学:化学(英文版)》2012,55(8):1683-1687,1,11
Certain N-cyanoalkyl-functionalized imidazolium halide salts unexpectedly undergo nitrile hydrolysis to amides, as well as dipolar cycloaddition to tetrazoles when eluted on azide anion exchanged resin. 相似文献
93.
The 1,3‐dipolar cycloaddition of an azomethine ylide generated by a decarboxylative route from sarcosine and isatin to 1‐benzyl‐3,5‐diarylmethylidene‐piperidin‐4‐ones afforded novel di‐spiro‐indolo/pyrrolidino/piperidines in moderate yields. Further cycloaddition of these di‐spiro compounds to nitrile oxide afforded tri‐spiro‐indolo/pyrrolidino/piperadino/isoxazolines in moderate yields with high regio‐ and stereoselectivity. 相似文献
94.
Fatima Setifi David K. Geiger Ibrahim Abdul Razak Zouaoui Setifi 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(8):658-663
Polynitrile anions are important in both coordination chemistry and molecular materials chemistry, and are interesting for their extensive electronic delocalization. The title compound crystallizes with two symmetry‐independent half 4,4′‐bipyridine‐1,1′‐diium (bpyH22+) cations and two symmetry‐independent 1,1,3,3‐tetracyano‐2‐ethoxypropenide (tcnoet−) anions in the asymmetric unit. One of the bpyH22+ ions is located on a crystallographic twofold rotation axis (canted pyridine rings) and the other is located on a crystallographic inversion center (coplanar pyridine rings). The ethyl group of one of the tcnoet− anions is disordered over two sites with equal populations. The extended structure exhibits two separate N—H...NC hydrogen‐bonding motifs, which result in a sheet structure parallel to (010), and weak C—H...NC hydrogen bonds form joined rings. Two types of multicenter CN...π interactions are observed between the bpyH22+ rings and tcnoet− anions. An additonal CN...π interaction between adjacent tcnoet− anions is observed. Using density functional theory, the calculated attractive energy between cation and anion pairs in the tcnoet−...π(bipyridinediium) interactions were found to be 557 and 612 kJ mol−1 for coplanar and canted bpyH22+ cations, respectively. 相似文献
95.
Effects of precipitated silica (PSi) and silica from fly ash (FA) particles (FASi) on the cure and mechanical properties before and after thermal and oil aging of natural rubber (NR) and acrylonitrile–butadiene rubber (NBR) blends with and without chloroprene rubber (CR) or epoxidized NR (ENR) as a compatibilizer have been reported in this paper. The experimental results suggested that the scorch and cure times decreased with the addition of silica and the compound viscosity increased on increasing the silica content. The mechanical properties for PSi filled NR/NBR vulcanizates were greater than those for FASi filled NR/NBR vulcanizates in all cases. The PSi could be used for reinforcing the NR/NBR vulcanizates while the silica from FA was regarded as a semi‐reinforcing and/or extending filler. The incorporation of CR or ENR enhanced the mechanical properties of the NR/NBR vulcanizates, the ENR being more effective and compatible with the blend. The mechanical properties of the NR/NBR vulcanizates were improved by post‐curing effect from thermal aging but deteriorated by the oil aging. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
96.
1,3-Dipolar cycloaddition of nitrile oxides generated in situ in the presence of variously substituted N-arylmaleimides and N-benzylmaleimide provides new pyrrolo[3,4-d]izoxazoline-4,6-diones in good yields. The whole procedure could be performed in a practical and efficient one-pot operation. All the cycloadducts were isolated in excellent yields and identified by spectral studies.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 444–448, March, 2009. 相似文献
97.
V. A. Ogurtsov O. A. Rakitin Yu. A. Strelenko N. V. Obruchnikova L. I. Khmel'nitskii 《Russian Chemical Bulletin》1993,42(4):706-708
Interaction of aromatic nitrile oxides with bis-trimethylsilylthiodiimide results in 2-amino-4-aryl-1,2,3,5-oxathiadiazoles, the first representatives of a new class of heterocyclic compounds.For Part 2, see ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 742–743, April, 1993. 相似文献
98.
芳腈在温和条件下进行锆氢化反应,所得产物经水解得到芳醛;若经酰基化则得到N-酰基不饱和胺。后者不稳定,在室温下与甲醇发生加成反应得N-(α-甲氧基苄基)苯甲酰胺。过量的锆氢化试剂与芳腈反应,继之进行酰基化,得到二元酰基化产物,两个酰基分别加到腈基的碳与氮原子上。 相似文献
99.
Paramagnetic nitrile oxide, a derivative of 3-imidazoline-1-oxyl, has been generated by thermolysis of geminal nitrooxime. This compound readily undergoes cycloaddition with alkenes with both activated and nonactivated C=C bonds. The paramagnetic nitrile oxide may be used for introducing a nitroxyl into molecules with multiple carbon-carbon bonds.For the previous communication, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 289–291, February, 1994. 相似文献
100.
The consecutive reaction of bis [ 2, 2, 2-trifluoroethyl] phosphite and its application to the one-pot synthesis of 3-cyano-β, γ-unsaturated nitriles with exdusive or predominant E-selectivity (E: Z = 100-85: 0-15) and excellent yields (94%-99%) are described. 相似文献