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91.
Mahmoudan Alireza Samadof Parviz Kumar Ravinder Jalili Mohamad Issakhov Alibek 《Journal of Thermal Analysis and Calorimetry》2021,145(3):1353-1372
Journal of Thermal Analysis and Calorimetry - Ensuring efficient operation of energy conversion systems in terms of economics and ecology is a prime objective that should be addressed within the... 相似文献
92.
Anhydrous zinc bromide catalysed reactions of arylidine‐3‐acetyl coumarins ( 1a‐c ) and 5,6‐benzoanalogs of arylidine 3‐acetyl coumarins ( 4a,4b ) with 1,3‐cyclohexanedione gives ‐(4‐aryl‐5‐oxo‐5,6,7,8‐tetrahydro‐4H‐chromen‐2yl)‐2H‐chromen‐2‐ones ( 3a, 3c ) and 5,6‐benzoanalogs of 3‐(4‐aryl‐5‐oxo‐5,6,7,8‐tetrahydro‐4H‐chromen‐2yl)‐2H‐chromen‐2‐one ( 5a,5b ). Under similar conditions arylidine‐3‐acetylcoumarins ( 1a, 1b,1d, 1e, 1f ) and 5,6‐benzoanalog of arylidine 3‐acetyl coumarin ( 4b ) react with 5,5‐dimethyl‐1,3‐cyclohexanedione (dimedone) yielding 3‐(4‐aryl‐7,7‐dimethyl‐5‐oxo‐5,6,7,8‐tetrahydro‐4H‐chromen‐2‐yl)‐2H‐chromen‐2‐ones ( 3d‐3h ) and the 5,6‐benzoanalog of 3.(4‐aryl‐7,7‐dimethyl‐5‐oxo‐5,6,7,8‐tetrahydro‐4H‐chromen‐2‐yl)‐2H‐chromen‐2‐one ( 5c ). 相似文献
93.
94.
Ravinder Chona 《Optics and Lasers in Engineering》1993,19(1-3)
A procedure for determining the fracture mechanics parameters of interest from full-field optical mechanics data is presented. Examples are presented for crack-tip stress fields recorded using dynamic photoelasticity. Stress-field representations in series form, when combined with local collocation procedures, are shown to be a powerful tool for reliable and accurate parameter determination. The methodology is illustrated and applied to two cases of dynamic crack propagation, one pertaining to opening-mode crack propagation and the other to a smoothly curving crack. Emphasis has been placed on giving guidance to a user on how best to approach implementation of the methodology from a practical standpoint. 相似文献
95.
Sirassu Narsimha Sathesh Kumar Nukala T. Savitha Jyostna M. Ravinder M. Srinivasa Rao N. Vasudeva Reddy 《Journal of heterocyclic chemistry》2020,57(4):1655-1665
In search of better antibacterial and anticancer agents, a series of novel 4-[3-fluoro-4-(morpholin-4-yl)]phenyl-1H-1,2,3-triazole derivatives were synthesized ( 6a - l and 8a - j ) by using 3-fluoro-4-morpholinoaniline, alkyne, and triflyl azide via an in situ generated 4-(4-azido-2-fluorophenyl)morpholine and evaluated for their antibacterial and anticancer activity in vitro. Antibacterial activity against three G+ bacterial strains and anticancer activity against breast cancer cell line (MCF-7) and cervical carcinoma cell line (HeLa) was evaluated. Among all the tested compounds, 6h , 6i , and 8b exhibited potent antibacterial activity against tested gram-positive bacterial strains. The anticancer activity screening results of 8f , 8h , and 8i exhibited potent cytotoxic activity against two cancer cell lines with IC50 values nearer to the standard drug, doxorubicin. The remaining compounds have shown good to moderate activity against the tested cell lines. On the basis of the results obtained, a structure-activity relationship (SAR) is discussed. 相似文献
96.
97.
Ring-opening of aziridines with potassium thiocyanate and thiols has efficiently been carried out at room temperature in the presence of sulfated zirconia to give the corresponding β-aminothiocyanates and β-aminosulfides, respectively, in high yields within 2 h and with high regioselectivity. The catalyst, a solid acid, functions under heterogeneous conditions. 相似文献
98.
Boyu Zhang Hong ZhangBrittany K. Myers Ravinder ElupulaJanarthanan Jayawickramarajah Scott M. Grayson 《Analytica chimica acta》2014
End groups play a critical role in macromolecular coupling reactions for building complex polymer architectures, yet their identity and purity can be difficult to ascertain using traditional analytical technique. Recent advances in mass spectrometry techniques have made matrix-assisted laser desorption/ionization time-of-fight (MALDI-TOF) mass spectrometry a rapid and powerful tool for providing detailed information about the identity and purity of homopolymer end groups. In this work, MALDI-TOF mass spectrometry was used to study end groups of linear polyethylene glycols. In particular, the identifications of alcohol, amine and thiol end groups are investigated because these nucleophilic moieties are among the most common within biological and synthetic macromolecules. Through comparative characterization of alcohol, amine, and thiol end groups, the exact identification of these end groups could be confirmed by selective and quantitative modification. The precision of this technique enables the unambiguous differentiation of primary amino groups relative to hydroxyl groups, which differ by only 1 mass unit. In addition, the quantitative conversion of various polyethylene glycol end groups using highly efficient coupling reactions such as the thiol-ene and azide-alkyne click reactions can be confirmed using MALDI-TOF mass spectrometry. 相似文献
99.
A novel multicomponent reaction involving phenacylbromide, thiosemicarbazide, and α-acetyl-γ-butyrolactone in the presence of POCl3, forming 7-methyl-5-[4-(aryl/heteryl)thiazole-2-yl]-5,8-diaza spiro[2,4]hept-6-en-4-ones in good yields, is described. 相似文献
100.
Dr. Aviva Levina Dr. Adriana Pires Vieira Asanka Wijetunga Dr. Ravinder Kaur Dr. Jordan T. Koehn Prof. Debbie C. Crans Prof. Peter A. Lay 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(37):15968-15972
The chemistry and short lifetimes of metal-based anti-cancer drugs can be turned into an advantage for direct injections into tumors, which then allow the use of highly cytotoxic drugs. The release of their less toxic decomposition products into the blood will lead to decreased toxicity and can even have beneficial effects. We present a ternary VV complex, 1 ([VOL1L2], where L1 is N-(salicylideneaminato)-N′-(2-hydroxyethyl)ethane-1,2-diamine and L2 is 3,5-di-tert-butylcatechol), which enters cells intact to induce high cytotoxicity in a range of human cancer cells, including T98g (glioma multiforme), while its decomposition products in cell culture medium were ≈8-fold less toxic. 1 was 12-fold more toxic than cisplatin in T98g cells and 6-fold more toxic in T98g cells than in a non-cancer human cell line, HFF-1. Its high toxicity in T98g cells was retained in the presence of physiological concentrations of the two main metal-binding serum proteins, albumin and transferrin. These properties favor further development of 1 for brain cancer treatment by intratumoral injections. 相似文献