全文获取类型
收费全文 | 580篇 |
免费 | 0篇 |
专业分类
化学 | 568篇 |
晶体学 | 2篇 |
数学 | 3篇 |
物理学 | 7篇 |
出版年
2023年 | 4篇 |
2022年 | 5篇 |
2021年 | 6篇 |
2020年 | 7篇 |
2019年 | 14篇 |
2018年 | 17篇 |
2017年 | 16篇 |
2016年 | 27篇 |
2015年 | 12篇 |
2014年 | 11篇 |
2013年 | 47篇 |
2012年 | 14篇 |
2011年 | 12篇 |
2010年 | 12篇 |
2009年 | 15篇 |
2008年 | 14篇 |
2007年 | 20篇 |
2006年 | 9篇 |
2005年 | 4篇 |
2004年 | 13篇 |
2003年 | 13篇 |
2002年 | 11篇 |
2001年 | 16篇 |
1996年 | 4篇 |
1995年 | 3篇 |
1994年 | 3篇 |
1993年 | 6篇 |
1992年 | 13篇 |
1991年 | 14篇 |
1990年 | 8篇 |
1989年 | 10篇 |
1988年 | 6篇 |
1987年 | 13篇 |
1986年 | 9篇 |
1985年 | 9篇 |
1984年 | 7篇 |
1983年 | 10篇 |
1982年 | 13篇 |
1981年 | 9篇 |
1979年 | 13篇 |
1978年 | 20篇 |
1977年 | 18篇 |
1976年 | 13篇 |
1975年 | 3篇 |
1972年 | 4篇 |
1971年 | 15篇 |
1970年 | 6篇 |
1969年 | 8篇 |
1967年 | 4篇 |
1966年 | 3篇 |
排序方式: 共有580条查询结果,搜索用时 218 毫秒
41.
42.
I. V. Konovalova L. A. Burnaeva E. K. Khusnutdinova A. N. Pudovik 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4)
Abstract Nucleophilicity of (I) in reactions with such carbonyl compounds as chloral, benzyl, ester and nitrile of benzoylformic acid is found to be notably reduced by the electronoaccepting perfluoropropyl groups. Unlike of dialkyl isocyanatophosphites (I) afford the cycloaddition products with ≡P-N- fragment (II) which being unable for the imide-amide rearrangement undergo dimerization into crystalline cyclodiphosphazanes (III) with pentacovalent phosphorus atoms. 相似文献
43.
44.
Rustem Kamalov Roza Al'myanova Michael Pudovik 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract Isothiocyanatochloromethyl(thio)phosphonates and (thio)-phosphinates 1 (X=O, S; R1 = OPh, CH2Cl, NCS; R2 = H, Cl have been found to be convenient starting material for synthesis of a variety of S (Se), N, P-containing cyclic compounds. They react with different proton containing nucleophiles in the presence of a base with formation of saturated 2 and unsaturated 3 five membered phosphacyclanes. Diisothiocyanatodichloromethylphosphonates 1 (R1 = NCS, R2 =Cl) produce with amines and thiols appropriate bicyclic compounds 4. 相似文献
45.
Il'yas S. Nizamov Elvira S. Batyeva Vladimir A. Al'fonsov Rashid Z. Musin Arkady N. Pudovik 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):229-237
Abstract The reactions of tetraphosphorus trisulfide with thioacetals, aminals, sulfenamides and disulfides were studied. The reactions were found to give organothiophosphorus compounds and to be facilitated by organic amines and benzoyl peroxide. 相似文献
46.
O. G. Sinyashin I. Yu. Gorshunov E. S. Batyeva A. N. Pudovik 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract A simple and effective method has been developed for synthesizing a new type of organophosphorus compounds, thiolophosphohydrides, with the general formula R(R′S)PH based on the selective reduction of thioesters of P(III) acids by di- or trialkylstannanes. Stable S-alkylalkylthiophos-phonites and S-alkylalkyldithiophosphonites have been obtained for the first time by using the processes of oxidation and sulfurization. The functionally substituted phosphorus (111) thio derivatives have been obtained by the addition reactions of thiolophosphohydrides with compounds containing carbon-carbon and carbon-oxygen multiple bonds, with the cleavage of the P-H bonds and the preservation of P-S bonds. Factors affecting the rate of interaction, stability and the structure of additional products have been elucidated. Depending on the reaction conditions of thiolophosphohydrides with halogen containing electrophilic reagents and on the nature of the latter, the process can lead to the cleavage either of the P-H bond or the P-S bond. Thiolophosphohydrides as new reagents in organophosphorus synthesis open up new vistas for obtaining a variety of functionally substituted phosphor- and sulfur-containing compounds. 相似文献
47.
48.
L. I. Vagapova L. R. Amirova E. Yu. Pavlova A. R. Burilov Yu. K. Voronina V. V. Syakaev D. R. Sharafutdinova I. Kh. Rizvanov A. R. Garifzyanov M. A. Pudovik 《Russian Journal of Organic Chemistry》2014,50(4):469-477
New α-amino acetals containing a phosphonate or phosphine oxide group were synthesized by the Kabachnik-Fields reaction in the ternary system amino acetal-paraformaldehyde-dialkyl phosphonate (or dialkylphosphine oxide). Condensation of dialkyl (2,2-dimethoxyethylamino)methylphosphonates with resorcinol and its derivatives in ethanol in the presence of hydrochloric acid, apart from the corresponding 2,2-bis(polyhydroxyphenyl) ethylammonium salts, gave 2,5-bis(polyhydroxyphenyl)-1,4-bis[(dialkoxyphosphoryl)methyl]-piperazines. Dialkyl[(2,2-dimethoxyethylamino)methyl]phosphine oxides (Alk = C8H17, C10H21) did not react with resorcinol derivatives under similar conditions, and analogous ammonium salts were obtained by heating the reactants in boiling trifluoroacetic acid. 相似文献
49.
Laxman Singh Ravikant Sharma Narayan Singh Atendra Kumar Dev K Mahato Youngil Lee Mikhael Bechelany KD Mandal 《Progress in Crystal Growth and Characterization of Materials》2021,67(4):100542
This review paper covers the low temperature wet growth of nano-engineered particles of ZnO-based mixed metal oxides, their growth mechanism, and characterization using X-ray diffraction, SEM, TEM and IR, UV–visible, and XPS spectral techniques. Main focus of this article is centered on low temperature semi-wet methods of synthesis that are suitable for large scale production of zinc oxide-based systems mixed with iron oxide, copper oxide, nickel oxide and cobalt oxide. These mixed metal oxides have broad industrial applications as catalyst, semiconductors, adsorbents, superconductors, electro-ceramics, and antifungal agents in addition to extensive applications in medicines. This paper discusses the low-cost and environment friendly synthesis of these mixed metal oxides, measurement of properties and applicability of these materials systems. 相似文献
50.
Azmukhanova R. R. Gibadullina E. M. Pazilova N. B. Pudovik M. A. Burilov A. R. 《Russian Journal of Organic Chemistry》2017,53(11):1746-1748
Russian Journal of Organic Chemistry - In reaction of diethyl [(3,5-di-tert-butyl-4-oxocyclohexa-2,5-diеn-1-ylidene)methyl]phosphonate with N 1,N 1-dimethylethane-1,2-diamine aminophosphonate... 相似文献