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81.
Priscilla Magalhes de Lima Gustavo Csar Dacanal Lorena Silva Pinho Samuel Henrique Gomes de S Marcelo Thomazini Carmen Sílvia Favaro-Trindade 《Molecules (Basel, Switzerland)》2022,27(21)
Reducing waste, using byproducts, and natural food additives are important sustainability trends. In this context, the aim of this study was to produce and evaluate a natural food dye, extracted from pumpkin byproducts, powdered and protected by spray-chilling (SC) and a combination of spray-drying and spray-chilling techniques (SDC). The extract was obtained using ethanol as solvent; vegetable fat and gum Arabic were used as carriers. Formulations were prepared with the following core:carrier ratios: SC 20 (20:80), SC 30 (30:70), SC 40 (40:60), SDC 5 (5:95), SDC 10 (10:90), and SDC 15 (15:85). The physicochemical properties of the formed microparticles were characterised, and their storage stability was evaluated over 90 days. The microparticles exhibited colour variation and size increase over time. SDC particles exhibited the highest encapsulation efficiency (95.2–100.8%) and retention of carotenoids in the storage period (60.8–89.7%). Considering the carotenoid content and its stability, the optimal formulation for each process was selected for further analysis. All of the processes and formulations produced spherical particles that were heterogeneous in size. SDC particles exhibited the highest oxidative stability index and the highest carotenoid release in the intestinal phase (32.6%). The use of combined microencapsulation technologies should be considered promising to protect carotenoid compounds. 相似文献
82.
de Oliveira Pedro Igor Camara de Santana Miranda Paulo Henrique Lourenço Estela Mariana Guimaraes de Santana Nogueira Silverio Priscilla Suene Barbosa Euzebio Guimaraes 《Molecular diversity》2021,25(4):2219-2235
Molecular Diversity - Chagas disease kills over 10,000 people per year, and approximately 8 million people are infected by Trypanosoma cruzi. The reference drug for treatment of the disease,... 相似文献
83.
Ludmila C. Fidale Constance Ißbrücker Priscilla L. Silva Camila M. Lucheti Thomas Heinze Omar A. El Seoud 《Cellulose (London, England)》2010,17(5):937-951
Although cellulose acetates, CAs, are extensively employed there is scant information about the systematic dependence of their properties on their degree of substitution, DS; this is the subject of the present work. Nine CAs samples, DS from
0.83 to 3.0 were synthesized; their films were prepared. The following solvatochromic probes have been employed in order to
determine the empirical polarity, E
T(33); “acidity, α”; “basicity, β”, and “dipolarity/polarizability, π*” of the casted films: 2,6-dichloro-4-(2,4,6-triphenyl-pyridinium-1-yl)
phenolate, WB; 4-nitroaniline; 4-nitroanisole; 4-nitro-N,N-dimethylaniline; 2,6-diphenyl-4-(2,4,6-triphenyl-pyridinium-1-yl)phenolate, RB. Additionally, two systems, ethanol plus ethyl
acetate (EtOH–EtAc), and cellulose plus cellulose triacetate, CTA, were employed as models for CAs of different DS. Regarding
the model systems, the following was observed: (i) For EtOH–EtAc, the dependence of all solvatochromic parameters on the “equivalent-DS”
of the binary mixture was non-linear because of preferential solvation; (ii) The dependence of E
T(33) on equivalent DS of the cellulose–CTA films is linear, but the slope is smaller than that of the corresponding plot for
CAs. This is attributed to the more efficient hydrogen bonding in the model system, a conclusion corroborated by IR measurements.
The dependence of solvatochromic parameters of CAs on their DS is described by the simple equations; a consequence of the
substitution of the OH by the ester group. The thermal properties of bulk CAs samples were investigated by DSC and TGA; their
dependence on DS is described by simple equations. The relevance of these data to the processing and applications of CAs is
briefly discussed. 相似文献
84.
Ida Malarselvi Rajkumar Deepika Asaithambi Ramachandra Raja Chidambaram Priscilla Rajkumar 《合成通讯》2020,50(17):2617-2628
Abstract This enhancement in the activity may be efficient on the basis that ligands mainly possess CH=N bond. The use of a structure-based drug design approach (SBDD) provides a way for investigation as well as to understand the molecular basis of the target protein and ligand molecule interactions at the atomic level. Structure-based drug design is the design and optimization of a chemical structure to identify a compound suitable for clinical testing the drug candidates. Chitosan is a polysaccharide with recognized biological activities for improving the functionality of polysaccharide 5-Fluorosalicylaldehyde aniline system. The used for selectively oxidized chitosan to produce tailored derivatives. C-2-5-Fluorosalicylaldehyde-C-6 aniline double Schiff base derivatives of chitosan were synthesized. The structure and properties of the newly synthesized product were characterized by FT-IR, 1H-NMR, 13C-NMR, GC-Mass spectroscopy, and thermal analysis (DSC/TGA). An exothermic process discusses a DSC and TGA analysis of thermal behavior of this polymer was shown to be a possible thermal polymerization of the double bonds in the polymer chains and thermo-oxidation of the polymer. 相似文献
85.
de Pádua Lima Fernandes Antônio Garcia Eric Marsalha de Almeida Rubens Moreira Taroco Hosane Aparecida Silva Edyth Priscilla Campos Domingues Rosana Zacarias Matencio Tulio 《Journal of Solid State Electrochemistry》2016,20(9):2575-2580
Journal of Solid State Electrochemistry - In this work, anode-supported solid oxide fuel cells (SOFC) were tested with a yttria-stabilized zirconia (YSZ) (8 mol%... 相似文献
86.
Lumetta GJ Rapko BM Garza PA Hay BP Gilbertson RD Weakley TJ Hutchison JE 《Journal of the American Chemical Society》2002,124(20):5644-5645
Evaluation of the malonamide substructure with respect to binding site preorganization and complementarity for lanthanide metal ions suggests a new ligand architecture specifically designed to enhance lanthanide ion affinity. Consideration of conformational reorganization, restricted bond rotation, and donor group orientation suggests that typical malonamide structures, for example, N,N,N'N'-tetrahexylpropane-1,3-diamide (1), N,N'-dibutyl-N,N'-dimethyl-2-tetradecylpropane-1,3-diamide (2), or N,N,N'N'-tetramethylpropane-1,3-diamide (6), are poorly organized for metal ion complexation. Molecular mechanics analyses show that the unfavorable enthalpic and entropic terms are eliminated by the use of the novel bicyclic architecture found in 3,9-diaza-3,9-dimethylbicyclo[4.4.0]decane-2,10-dione (7). Diamide 7 was prepared, and the X-ray crystal structure of the complex [Eu(7)(2)(NO(3))(3)] exhibits the same chelate conformation predicted by the molecular mechanics model. A hydrophobic derivative, 3,9-diaza-3,9-dioctylbicyclo[4.4.0]decane-2,10-dione (8), was prepared, and solvent extraction studies reveal that the preorganized architecture of 8 gives a dramatic enhancement in binding affinity, exhibiting Eu(3+) distribution coefficients that are 7 orders of magnitude larger than a typical malonamide ligand, 1. 相似文献
87.
Mekassa Birhanu Baker Priscilla G. L. Chandravanshi Bhagwan Singh Tessema Merid 《Journal of Solid State Electrochemistry》2018,22(11):3607-3619
Journal of Solid State Electrochemistry - In this work, nickel nanoparticles (NiNPs) and graphene oxide (GO) were synthesized and characterized independently using spectroscopic and microscopic... 相似文献
88.
89.
Volcke C Simonis P Durant F Thiry PA Lambin P Culot C Humbert C 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(14):4185-4190
The influence of chemical modification of scanning tunnelling microscopy tips on image contrast is studied. This technique is applied to the identification of an ester functional group, hardly visible otherwise. Self-assembled overlayers of wax esters [CH3-(CH2)14-CO-O-(CH2)15-CH3], adsorbed at the interface between highly oriented pyrolitic graphite and a solution of phenyloctane, are imaged. The gold tips used are chemically modified by 4-mercaptobenzoic acid and 4-mercaptotoluene. The stability of the ordered overlayers formed facilitates the reproducible set of images with submolecular resolution. This allows the identification of the layer regular structure and of other features within molecules, which can be unambiguously related to the fingerprints of the COO bond. Moreover, we are interested in finding evidence of molecular motions observed at domain boundaries. 相似文献
90.
Jos A. Figueira Priscilla Porto-Figueira Cristina Berenguer Jorge A. M. Pereira Jos S. Cmara 《Molecules (Basel, Switzerland)》2021,26(14)
In this study, the health-promoting benefits of different fruits grown in Madeira Island, namely lemon (Citrus limon var. eureka), tangerine (Citrus reticulata var. setubalense), pitanga (Eugenia uniflora var. red), tomato (Solanum lycopersicum var. gordal) and uva-da-serra, an endemic blueberry (Vaccinium padifolium Sm.), were investigated. The phenolic composition (total phenolics and total flavonoids content) and antioxidant capacity (assessed through ABTS and DPPH assays) were measured revealing a high phenolic potential for all fruits, except tomato, while uva-da-serra is particularly rich in flavonoids. In relation to the antioxidant capacity, the highest values were obtained for pitanga and uva-da-serra extracts. The bioactive potential was also assessed through the ability of the extracts to inhibit digestive enzymes linked to diabetes (α-amylase, α- and β-glucosidases) and hypertension (angiotensin-converting enzyme, ACE). The results obtained point to a very high bioactive potential with the selected samples exhibiting very important ACE anti-enzymatic capacities. A statistical analysis of the obtained data reveals a very strong correlation between ABTS and TPC, and a strong contribution of the fruit polyphenols for enzyme inhibition, and thus, presenting high antihypertensive and antidiabetic capacities. Overall, the results obtained clearly show a high bioactive potential of the selected fruits that should be further studied, in terms of specific phenolic composition. Moreover, these results strongly support the valorisation of pitanga seeds usually discarded as a waste, and uva-da-serra, an endemic and wild bush, as potential bioresources of bioactive compounds with impact in human diet. 相似文献