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81.
Background
The extracts from the aerial parts of Portulaca quadrifida have been reported to show the total flavonoid content, antioxidant and antibacterial activities.Results
Our results revealed that the total flavonoid content of methanol and chloroform extracts is 2.335?±?0.0097 and 1.7312?±?0.0082 mgQE/100 g respectively. The two extracts also showed good antioxidant activity and total phenolic content as well as weak to moderate antibacterial activity against some bacteria.Conclusions
The extracts the aerial parts of the P. quadrifida showed good total flavonoid content, DPPH radical scavenging activity and antibacterial activity. In addition to this, the extracts also showed the presence of some important compounds by phytochemical analysis.
82.
A. T. Soldatenkov I. A. Bekro Zh. A. Mamyrbekova S. A. Soldatova A. Temesgen N. D. Sergeeva L. N. Kuleshova V. N. Khrustalev 《Chemistry of Heterocyclic Compounds》1996,32(2):197-201
N-Alkyl substituted 4 phenyl-1.2,5,6-tetrahydropyridines which do not undergo Wagner hydroxylation are converted in good yields to the corresponding 3,4-dihydroxy-2-oxopiperidines under modified conditions for this reaction. The molecular structures of a 3,4-dihydroxy-4-phenylpiperidin-2-one and its diacetatate have been studied by x-ray crystalographic analysis.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 222–226, February, 1996. 相似文献
83.
Letícia R. Teixeira Rubén D. Sinisterra Rafael P. Vieira Aline Scarlatelli-Lima Márcio F.D. Moraes Maria Carolina Doretto Ângelo M. Denadai Heloisa Beraldo 《Journal of inclusion phenomena and macrocyclic chemistry》2006,54(1-2):133-138
A non-hygroscopic pharmaceutical composition was obtained following a host-guest strategy that used the anticonvulsant drug
sodium valproate (VA) and α-cyclodextrin. The pharmaceutical composition was fully characterized by thermal analyses (TG/DTG,
DSC), X-ray powder diffraction and by 1H, 13C, hydrogen relaxation times (T1) and 2D-ROESY NMR techniques. Isothermal titration calorimetry (ITC) was used to determine the VA:α-CD 1:1 stoichiometry
as well as to calculate the equilibrium constant (K) and thermodynamic energies of interaction (ΔGo, ΔHo and TΔSo). 相似文献
84.
Sahel Fajal Atikur Hassan Writakshi Mandal Mandar M. Shirolkar Sumanta Let Neeladri Das Sujit K. Ghosh 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(1):e202214095
In case of pollutant segregation, fast mass diffusion is a fundamental criterion in order to achieve improved performance. The rapid mass transport through porous materials can be achieved by availing large open pores followed by easy and complete accessibility of functional sites. Inducing macroporosity into such materials could serve as ideal solution providing access to large macropores that offer unhindered transport of analyte and full exposure to interactive sites. Moreover, the challenge to configure the ionic-functionality with macroporosity could emerge as an unparalleled avenue toward pollutants separation. Herein, we strategized a synthetic protocol for construction of a positively charged hierarchically-porous ordered interconnected macro-structure of organic framework where the size and number of macropores can easily be tuned. The ordered macropores with strong electrostatic interaction synergistically exhibited ultrafast removal efficiency towards various toxic pollutants. 相似文献
85.
Ingrid F. Zattoni Lais D. Guanaes Letícia B. Cerqueira Roberto Pontarolo Diogo R.B. Ducatti M. Eugênia R. Duarte Miguel D. Noseda Angela C.L.B. Trindade Alan G. Gonçalves 《Tetrahedron letters》2019,60(40):151129
We have evaluated four 1,4-dihydropyridines (DHPs 1a, 1b, 1c and 1d) as reducing agents, which presented free (hydrogenated) or phenyl-substituted N-1 and C-4 positions of the DHP ring. Reactions combining each of the DHP and different amounts of BF3OEt2 were evaluated for the reduction of imine 2a (N-benzylideneaniline). DHP simultaneously substituted at N-1 and C-4 (1a), and DHP substituted at C-4 (1b) gave lower yields for reduction of 2a in comparison with DHPs 1c and 1d (both unsubstituted at the C-4 position). By evaluating the amount of added BF3OEt2 to the reaction mixture, we have found that DHP 1c (substituted at N-1) provided its best yield for amine 3a (82%) when associated with stoichiometric amounts BF3OEt2, while DHP 1d (N-1- and C-4-unsubstituted derivative) was more effective (90% yield) with catalytic quantities of the Lewis acid. The reaction system using DHP 1c under stoichiometric BF3OEt2 could also be successfully applied with additional imine examples and under reductive amination conditions. 相似文献
86.
对高能激光大气传输非线性问题的数值模拟进行了计算方法的研究。用快速富里叶变换法和分量分离法进行了理论分析和数值对比计算,两种方法都达到二阶精度,分量分离法计算稳定性比较好,运算速度快。 相似文献
87.
de Lima Melchiades Gabriela Angeli Valéria Weiss Colombo Mariana Koester Letícia Scherer 《Journal of Thermal Analysis and Calorimetry》2020,142(3):1249-1260
Journal of Thermal Analysis and Calorimetry - Compatibility is an important step in pre-formulation studies during the development of solid dosage forms. In the present study, we used thermal... 相似文献
88.
Franciele Queiroz Ames Lívia Bracht Francielle Sato Lidiane Vizioli de Castro-Hoshino Bruno Ambrósio da Rocha Letícia Aparecida de Oliveira 《Natural product research》2020,34(16):2341-2345
Abstract Fish oil (FO) is a natural source of omega-3 fatty acids, with well-established beneficial effects in inflammatory diseases when FO is orally administered. This study investigated the effects of a topically applied FO preparation (FOP) on phenol-induced ear edema and evaluated the percutaneous penetration of FOP in ear tissue. After applying phenol, groups of mice received FOP on the ear. After 1?h, ear tissue was collected to determine the percent inhibition of edema, myeloperoxidase activity, and to perform photoacoustic spectroscopy (PAS). Treatment with FOP did not reduce edema, but reduced myeloperoxidase activity. The FOP decreased the area of bands that characterize inflamed tissue and penetrated into the tissue. These results indicated an inhibitory effect of FOP on leukocyte recruitment in phenol-induced ear edema. These data support the applicability of PAS as a non-destructive method for evaluating the inflammatory response, percutaneous penetration and antiinflammatory activity of compounds. 相似文献
89.
Dr. Kelly A. D. F. Castro Letícia D. Costa Juliana A. Prandini Dr. Juliana C. Biazzotto Prof. Dr. Augusto C. Tomé Prof. Dr. Michael R. Hamblin Prof. Dr. Maria da Graça P. M. S. Neves Prof. Dr. M. Amparo F. Faustino Prof. Dr. Roberto S. da Silva 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(6):1990-1994
Photodynamic therapy (PDT) is a promising alternative to overcome the resistance of melanoma to conventional therapies. Currently applied photosensitizers (PS) are often based on tetrapyrrolic macrocycles like porphyrins. Unfortunately, in some cases the use of this type of derivative is limited due to their poor solubility in the biological environment. Feasible approaches to surpass this drawback are based on lipid formulations. Besides that, and inspired in the efficacy of potassium iodide (KI) for antimicrobial photodynamic therapy (aPDT), the combined effect of singlet oxygen (1O2) with KI was assessed in this work, as an alternative strategy to potentiate the effect of PDT against resistant melanoma cells. 相似文献