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981.
Synthesis of 1‐Arylethyl‐2‐arylethylamino‐5‐trifluoroacetyl‐1,2,3,4‐tetrahydropyridines and Related Compounds with Potential Cell Efflux Pump Inhibition 下载免费PDF全文
Nilo Zanatta Marcio M. Lobo Josiane M. dos Santos Laura de A. Souza Valquiria P. de Andrade Helio G. Bonacorso Marcos A. P. Martins 《Journal of heterocyclic chemistry》2015,52(6):1776-1781
This study reports a simple, fast, and efficient method for the synthesis of a new series of 1‐arylethyl‐2‐arylethylamino‐5‐trifluoroacetyl‐1,2,3,4‐tetrahydropyridines and related compounds from the reaction of 2‐alkoxy‐5‐trifluoroacetyl‐3,4‐dihydro‐2H‐pyrans with 2‐arylethanamines and related 2‐ethanamines. The desired tetrahydropyridines were obtained in excellent yields (90–98%), through a reaction that can be described as an AAB′ three‐component reaction protocol following an ANRORC‐type mechanism. 相似文献
982.
Priscilla Mendes Arruda Antônio Canal Neto Mauro Cesar Martins Campos Henrique Raulino Coelho da Cruz Fábio Alves dos Santos 《International journal of quantum chemistry》2015,115(2):77-83
The Monte Carlo simulated annealing method is adapted to optimize correlated Gaussian‐type functions in nonrelativistic molecular environments. Starting from an atom‐centered atomic Gaussian basis set, the uncontracted functions are reoptimized in the molecular environments corresponding to the H2O, CN?, N2, CO, BF, NO+, CO2, and CS systems. These new molecular adapted basis sets are used to calculate total energies, harmonic vibrational frequencies, and equilibrium geometries at a correlated level of theory. The present methodology is a simple and effective way to improve molecular correlated wave functions, without the need to enlarge the molecular basis set. Additionally, this methodology can be used to generate hierarchical sequences of molecular basis sets with increasing size, which are relevant to establish complete basis set limits. © 2014 Wiley Periodicals, Inc. 相似文献
983.
Dr. Vinayaraj Ozhukil Kollath Freya Van den Broeck Dr. Krisztina Fehér Prof. José C. Martins Dr. Jan Luyten Dr. Karl Traina Dr. Steven Mullens Prof. Rudi Cloots 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(29):10497-10505
Biocompatible inorganic nano‐ and microcarriers can be suitable candidates for protein delivery. This study demonstrates facile methods of functionalization by using nanoscale linker molecules to change the protein adsorption capacity of hydroxyapatite (HA) powder. The adsorption capacity of bovine serum albumin as a model protein has been studied with respect to the surface modifications. The selected linker molecules (lysine, arginine, and phosphoserine) can influence the adsorption capacity by changing the electrostatic nature of the HA surface. Qualitative and quantitative analyses of linker‐molecule interactions with the HA surface have been performed by using NMR spectroscopy, zeta‐potential measurements, X‐ray photoelectron spectroscopy, and thermogravimetric analyses. Additionally, correlations to theoretical isotherm models have been calculated with respect to Langmuir and Freundlich isotherms. Lysine and arginine increased the protein adsorption, whereas phosphoserine reduced the protein adsorption. The results show that the adsorption capacity can be controlled with different functionalization, depending on the protein–carrier selections under consideration. The scientific knowledge acquired from this study can be applied in various biotechnological applications that involve biomolecule–inorganic material interfaces. 相似文献
984.
André Talvani Maria Terezinha Bahia Lívia Cristina Lira de Sá-Barreto Eliana Martins Lima Marcílio Sérgio Soares da Cunha-Filho 《Journal of Thermal Analysis and Calorimetry》2014,115(3):2501-2506
Carvedilol (CARVE) is an important cardiovascular drug with limited bioavailability. To improve its therapeutic performance, the investigation of new dosage forms is of great interest due its relevance in clinical applications. Therefore, the aim of this work was to evaluate the stability of CARVE and its drug–excipient compatibility to support its pharmaceutical development. Kinetic analysis under isothermal conditions using thermogravimetry was performed to determine the activation energy of CARVE through an Arrhenius plot. Differential scanning calorimetry, Fourier transform infrared spectroscopy, and optical microscopy were used to test binary mixtures of CARVE and selected excipients. The activation energy of CARVE was 81.2 kJ mol?1, and from the compatibility studies, all the excipients showed strong thermal interactions, presenting changes in the melting profile of the drug. In addition, analytical assays revealed no physical or chemical changes; because of this, all eight excipients studied are considered compatible and are recommended in formulations containing CARVE. All the evidence together attests to the low chemical reactivity of CARVE and provides useful information for the development of new pharmaceutical formulations containing CARVE. 相似文献
985.
New RuII(arene) Complexes with Halogen‐Substituted Bis‐ and Tris(pyrazol‐1‐yl)borate Ligands 下载免费PDF全文
Dr. Serena Orbisaglia Dr. Corrado Di Nicola Prof. Fabio Marchetti Prof. Claudio Pettinari Dr. Riccardo Pettinari Prof. Luísa M. D. R. S. Martins Prof. Elisabete C. B. A. Alegria Prof. M. Fátima C. Guedes da Silva Bruno G. M. Rocha Dr. Maxim L. Kuznetsov Prof. Armando J. L. Pombeiro Prof. Brian W. Skelton Dr. Alexandre N. Sobolev Prof. Allan H. White 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(13):3689-3704
[RuCl(arene)(μ‐Cl)]2 dimers were treated in a 1:2 molar ratio with sodium or thallium salts of bis‐ and tris(pyrazolyl)borate ligands [Na(Bp)], [Tl(Tp)], and [Tl(TpiPr, 4Br)]. Mononuclear neutral complexes [RuCl(arene)(κ2‐Bp)] ( 1 : arene=p‐cymene (cym); 2 : arene=hexamethylbenzene (hmb); 3 : arene=benzene (bz)), [RuCl(arene)(κ2‐Tp)] ( 4 : arene=cym; 6 : arene=bz), and [RuCl(arene)(κ2‐TpiPr, 4Br)] ( 7 : arene=cym, 8 : arene=hmb, 9 : arene=bz) have been always obtained with the exception of the ionic [Ru2(hmb)2(μ‐Cl)3][Tp] ( 5′ ), which formed independently of the ratio of reactants and reaction conditions employed. The ionic [Ru(CH3OH)(cym)(κ2‐Bp)][X] ( 10 : X=PF6, 12 : X=O3SCF3) and the neutral [Ru(O2CCF3)(cym)(κ2‐Bp)] ( 11 ) have been obtained by a metathesis reaction with corresponding silver salts. All complexes 1 – 12 have been characterized by analytical and spectroscopic data (IR, ESI‐MS, 1H and 13C NMR spectroscopy). The structures of the thallium and calcium derivatives of ligand Tp, [Tl(Tp)] and [Ca(dmso)6][Tp]2 ? 2 DMSO, of the complexes 1 , 4 , 5′ , 6 , 11 , and of the decomposition product [RuCl(cym)(HpziPr, 4Br)2][Cl] ( 7′ ) have been confirmed by using single‐crystal X‐ray diffraction. Electrochemical studies showed that 1 – 9 and 11 undergo a single‐electron RuII→RuIII oxidation at a potential, measured by cyclic voltammetry, which allows comparison of the electron‐donor characters of the bis‐ and tris(pyrazol‐1‐yl)borate and arene ligands, and to estimate, for the first time, the values of the Lever EL ligand parameter for Bp, Tp, and TpiPr, 4Br. Theoretical calculations at the DFT level indicated that both oxidation and reduction of the Ru complexes under study are mostly metal‐centered with some involvement of the chloride ligand in the former case, and also demonstrated that the experimental isolation of the μ3‐binuclear complex 5′ (instead of the mononuclear 5 ) is accounted for by the low thermodynamic stability of the latter species due to steric reasons. 相似文献
986.
Luiz Carlos Martins Das Neves Tábata Taemi Miazaki Ohara Miyamura Dante Augusto Moraes Thereza Christina Vessoni Penna Attilio Converti 《Applied biochemistry and biotechnology》2006,129(1-3):130-152
Industrial effluents from the pharmaceutical industry often contain high concentrations of phenolic compounds. The presence
of “anthropogenic” organic compounds in the environment is a serious problem for human health; therefore, it merits special
attention by the competent public agencies. Different methods have been proposed in the last two decades for the treatment
of this kind of industrial residues, the most important of which are those utilizing absorption columns, vaporization and
extraction, and biotechnological methods. Biofiltration is a method for the removal of contaminants present in liquid or gaseous
effluents by the use of aerobic microorganisms, which are immobilized on solid or porous supports. Although several bacteria
can utilize aromatic compounds as carbon and energy source, only a few of them are able to make this biodegradation effectively
and with satisfactory rate. For this reason, more investigation is needed to ensure an efficient control of process parameters
as well as to select the suited reactor configuration. The aim of this work is to provide an overview on the main aspects
of biofiltration for the treatment of different industrial effluents, with particular concern to those coming from pharmaceutical
industry and laboratories for the production of galenicals. 相似文献
987.
de Araújo Gabriela Martins Codognoto Lucia Simões Fábio Ruiz 《Journal of Solid State Electrochemistry》2020,24(8):1857-1866
Journal of Solid State Electrochemistry - In this work, composites based on polyaniline (PAni) grafted with reduced graphene oxide (rGO) were obtained by the in situ chemical polymerization of... 相似文献
988.
Eliane Teixeira Sousa Frederico de M. Rodrigues Cludio C. Martins Fabio Santos de Oliveira Pedro Afonso de P. Pereira Jailson B. de Andrade 《Microchemical Journal》2006,82(2):142-149
Peppers are used not only in cookery, but also in many other applications, like cosmetic, pharmaceutical and nourishing industry. The chemical composition of peppers is quite complex and several volatile and non-volatile substances contribute to their flavor, which is an important sensorial propriety. In this work a headspace/solid phase microextraction/gas chromatography coupled to mass spectrometry method was developed to evaluate the profiles of volatile compounds that contribute to the aroma of red, yellow and purple varieties of Capsicum chinense sp. peppers. The optimization of the extraction conditions was carried out using multivariate strategies such as factorial design and response surface methodology. The GC-MS analysis allowed the tentative identification of 34 compounds, with similarities higher than 85%, in accordance with the NIST mass spectral library. The data obtained by the analysis of volatile compounds, according to the proposed method, were treated with PCA chemometrics tool in order to group different varieties of C. chinense sp. peppers with similar VOC profiles. Amongst the most abundant VOCs, hexyl ester of pentanoic acid, dimethylcyclohexanols, humulene and esters of butanoic acid were found. Principal component analysis turned possible to visualize the grouping tendencies of the studied varieties of pepper, as well as the identification of the volatile compounds responsible for discriminating the three groups. Considering the fact that many species of peppers are used as human food, the significance of this work is further emphasized by its applicability to the study of food quality indicators, and as a tool for investigations on the composition of the pepper sources. 相似文献
989.
Moraes Amanda Naves Ferreira Silva Luís Antônio Dantas de Oliveira Maysa Aparecida de Oliveira Eder Magno Nascimento Thais Leite Lima Eliana Martins Torres Ieda Maria Sapateiro Diniz Danielle Guimarães Almeida 《Journal of Thermal Analysis and Calorimetry》2020,140(5):2283-2292
Journal of Thermal Analysis and Calorimetry - Hydroxychloroquine is effectively used in the treatment for malaria, lupus erythematosus and rheumatoid arthritis. The study of drug–excipient... 相似文献
990.
Duy‐Khiet Ho Xabier Murgia Chiara De Rossi Rebekka Christmann Antonio G. Hüfner de Mello Martins Marcus Koch Anastasia Andreas Jennifer Herrmann Rolf Müller Martin Empting Rolf W. Hartmann Didier Desmaele Brigitta Loretz Patrick Couvreur Claus‐Michael Lehr 《Angewandte Chemie (International ed. in English)》2020,59(26):10292-10296
Elimination of pulmonary Pseudomonas aeruginosa (PA) infections is challenging to accomplish with antibiotic therapies, mainly due to resistance mechanisms. Quorum sensing inhibitors (QSIs) interfering with biofilm formation can thus complement antibiotics. For simultaneous and improved delivery of both active agents to the infection sites, self‐assembling nanoparticles of a newly synthesized squalenyl hydrogen sulfate (SqNPs) were prepared. These nanocarriers allowed for remarkably high loading capacities of hydrophilic antibiotic tobramycin (Tob) and a novel lipophilic QSI at 30 % and circa 10 %, respectively. The drug‐loaded SqNPs showed improved biofilm penetration and enhanced efficacy in relevant biological barriers (mucin/human tracheal mucus, biofilm), leading to complete eradication of PA biofilms at circa 16‐fold lower Tob concentration than Tob alone. This study offers a viable therapy optimization and invigorates the research and development of QSIs for clinical use. 相似文献