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排序方式: 共有427条查询结果,搜索用时 15 毫秒
91.
92.
Abbasi Malek Kruger Alexander Y. Théra Michel 《Set-Valued and Variational Analysis》2021,29(3):701-719
Set-Valued and Variational Analysis - This paper proposes three enlargements of the conventional Moreau–Rockafellar subdifferential: the sup-, sup?- and symmetric subdifferentials. They... 相似文献
93.
The theoretical study focused on the possible use of low-molecular-weight mono-as well as multifunctional terminal alkynes as catalysts for two reactions, which are known to be typically acid catalyzed - acetalization and esterification, is presented in this study. Multifunctional terminal alkynes [(diethynylbenzenes, triethynylbenzene, and tetrakis(4-ethynylphenyl)methane] were significantly more active than the monofunctional ones (cyclopropylacetylene, phenylacetylene, 3-cyclohexylprop-1-yne, 1-ethynyl-2-fluorobenzene, 1-ethynyl-4-fluorobenzene, 4-ethynyltoluene, 4-tert-butylphenylacetylene, and 2-ethynyl-α,α,α-trifluorotoluene), this fact can be partly explained by the higher amount of ethynyl groups per alkyne molecule. We confirmed that terminal ethynyl groups in low-molecular-weight alkynes can successfully act as acid catalytic centers for acetalization as well as for esterification. 相似文献
94.
Ghasem Marandi Niloufar Akbarzadeh Torbati Reza Heydari Nourallah Hazeri Sayyed Mostafa Habibi-Khorassani Malek Taher Maghsoodlou 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1450-1461
A series of diverse NH- and CH-acids are used for a one-pot synthesis of stable phosphorus ylides and 1,4-diionic organophosphorus compounds by trapping of the zwitterionic intermediate from the reaction between triphenylphosphine and dialkyl acetylenedicarboxylates under solvent-free conditions. The structural geometry for one of the products was confirmed by single crystal X-ray diffraction analysis. 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
95.
Alexey N. Egorochkin Olga V. Kuznetsova Nadiya M. Khamaletdinova Lada G. Domratcheva-Lvova Georgy A. Domrachev 《Journal of organometallic chemistry》2009,694(9-10):1447-1452
The literature date on substituent influence on the carbonyl stretching frequencies (ν), CO stretching force constants (k), as well as 13C NMR carbonyl chemical shifts (δ) have been analyzed for 19 series of the transition metal carbonyl complexes. It was established for the first time that the ν, k and δ values depend not only on the inductive and resonance effects but also on the polarizability of substituents. The polarizability contribution ranges up to 37%. 相似文献
96.
Faroughi Niya Homayoun Hazeri Nourallah Rezaie Kahkhaie Mahboobeh Maghsoodlou Malek Taher 《Research on Chemical Intermediates》2020,46(3):1685-1704
Research on Chemical Intermediates - In this study, an efficient and novel procedure has been reported for loading sulfanilic acid on the surface of magnetite Fe3O4 nanoparticles using... 相似文献
97.
98.
Lada Zmostn Thomas Braun Beatrice Braun 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(10):2783-2787
The degradation of SF6 and SF5 organyls by S F and S C bond‐activation reactions at [{Rh(μ‐H)(dippp)}2] under mild conditions is reported. Fluorido and thiolato species were identified as products or intermediates, and were characterized by X‐ray diffraction analysis and multinuclear NMR spectroscopy. An unprecedented cyclic process for the conversion of the potent greenhouse gas SF6 into H2S was developed. 相似文献
99.
Nader Saad Brosse Nicolas Khadraoui Malek Fuentealba Cecilia Ziegler-Devin Isabelle Quils Fabienne El-Kirat-Chatel Sofiane Mauret Evelyne 《Cellulose (London, England)》2022,29(10):5593-5607
Cellulose - Micro- and Nano-Fibrillated Cellulose (MNFC) have gained increasing attention due to their remarkable properties, but their production usually requires an intensive multi-step process.... 相似文献
100.
Mehrnoosh?Kangani Nourallah?HazeriEmail author Malek?Taher?Maghsoodlou Khatereh?Khandan-Barani Maryam?Kheyrollahi Fereshteh?Nezhadshahrokhabadi 《Journal of the Iranian Chemical Society》2015,12(1):47-50
Saccharose was applied as an efficient and homogeneous catalyst for one-pot, four-component synthesis of 1,4-dihydropyrano[2,3-c]pyrazole derivatives from aromatic aldehydes, malononitrile, ethyl acetoacetate and hydrazine monohydrate under thermal solvent-free conditions. This protocol has a considerable number of advantages including mild condition, high yields, operational simplicity, environmentally benign and simple work-up procedures. 相似文献