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51.
Dipl.‐Chem. Nicolas Dietl Dr. Anna Troiani Dr. Maria Schlangen Dr. Ornella Ursini Dr. Giancarlo Angelini Prof. Dr. Yitzhak Apeloig Prof. Dr. Giulia de Petris Prof. Dr. Helmut Schwarz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(21):6662-6669
The reactivity of the two diatomic congeneric systems [CO].+ and [SiO].+ towards methane has been investigated by means of mass spectrometry and quantum‐chemical calculations. While [CO].+ gives rise to three different reaction channels, [SiO].+ reacts only by hydrogen‐atom transfer (HAT) from methane under thermal conditions. A theoretical analysis of the respective HAT processes reveals two distinctly different mechanistic pathways for [CO].+ and [SiO].+, and a comparison to the higher metal oxides of Group 14 emphasizes the particular role of carbon as a second‐row p element. 相似文献
52.
Dr. Maria Petrosino Dr. Francesco Stellato Prof. Roberta Chiaraluce Prof. Valerio Consalvi Dr. Giovanni La Penna Dr. Alessandra Pasquo Dr. Olivier Proux Prof. Giancarlo Rossi Prof. Silvia Morante 《ChemistryOpen》2021,10(11):1133-1141
We present in this work a first X-ray Absorption Spectroscopy study of the interactions of Zn with human BST2/tetherin and SARS-CoV-2 orf7a proteins as well as with some of their complexes. The analysis of the XANES region of the measured spectra shows that Zn binds to BST2, as well as to orf7a, thus resulting in the formation of BST2-orf7a complexes. This structural information confirms the the conjecture, recently put forward by some of the present Authors, according to which the accessory orf7a (and possibly also orf8) viral protein are capable of interfering with the BST2 antiviral activity. Our explanation for this behavior is that, when BST2 gets in contact with Zn bound to the orf7a Cys15 ligand, it has the ability of displacing the metal owing to the creation of a new disulfide bridge across the two proteins. The formation of this BST2-orf7a complex destabilizes BST2 dimerization, thus impairing the antiviral activity of the latter. 相似文献
53.
A. Akindinov A. Alici P. Antonioli S. Arcelli M. Basile G. Cara Romeo M. Chumakov L. Cifarelli F. Cindolo A. De Caro D. De Gruttola S. De Pasquale M. Fusco Girard C. Guarnaccia D. Hatzifotiadou H.T. Jung W.W. Jung D.W. Kim H.N. Kim J.S. Kim S. Kiselev G. Laurenti K. Lee S.C. Lee E. Lioublev M.L. Luvisetto A. Margotti A. Martemiyanov R. Nania F. Noferini P. Pagano A. Pesci R. Preghenella G. Russo E. Scapparone G. Scioli R. Silvestri Y. Sun I. Vetlitskiy K. Voloshin L. Vorobiev M.C.S. Williams B. Zagreev C. Zampolli A. Zichichi 《The European Physical Journal C - Particles and Fields》2007,50(2):341-352
In this work we explore the possibility to perform “effective energy” studies in very high energy collisions at the CERN large
hadron collider (LHC). In particular, we focus on the possibility to measure in pp collisions the average charged multiplicity
as a function of the effective energy with the ALICE experiment, using its capability to measure the energy of the leading
baryons with the zero degree calorimeters. Analyses of this kind have been done at lower centre-of-mass energies and have
shown that, once the appropriate kinematic variables are chosen, particle production is characterized by universal properties:
no matter the nature of the interacting particles, the final states have identical features. Assuming that this universality
picture can be extended to ion–ion collisions, as suggested by recent results from RHIC experiments, a novel approach based on the scaling hypothesis for limiting
fragmentation has been used to derive the expected charged event multiplicity in AA interactions at LHC. This leads to scenarios
where the multiplicity is significantly lower compared to most of the predictions from the models currently used to describe
high energy AA collisions. A mean charged multiplicity of about 1000–2000 per rapidity unit (at η∼0) is expected for the most
central Pb–Pb collisions at .
In memory of A. Smirnitskiy 相似文献
54.
Dr. Andrea Previtali Dr. Wei He Dr. Alessandra Forni Dr. Daniele Malpicci Dr. Elena Lucenti Dr. Daniele Marinotto Prof. Lucia Carlucci Prof. Pierluigi Mercandelli Dr. Marco Aldo Ortenzi Prof. Giancarlo Terraneo Dr. Chiara Botta Prof. Ryan Tsz Kin Kwok Dr. Jacky Wing Yip Lam Prof. Ben Zhong Tang Prof. Elena Cariati 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(67):16690-16700
Organic materials with multiple emissions tunable by external stimuli represent a great challenge. TTPyr, crystallizing in different polymorphs, shows a very rich photophyisics comprising excitation-dependent fluorescence and phosphorescence at ambient conditions, and mechanochromic and thermochromic behavior. Transformation among the different species has been followed by thermal and X-ray diffraction analyses and the emissive features interpreted through structural results and DFT/TDDFT calculations. Particularly intriguing is the polymorph TTPyr(HT), serendipitously obtained at high temperature but stable also at room temperature, whose non-centrosymmetric structure guarantees an SHG efficiency 10 times higher than that of standard urea. Its crystal packing, where only the TT units are strongly rigidified by π-π stacking interactions while the Pyr moieties possess partial conformational freedom, is responsible for the observed dual fluorescence. The potentialities of TTPyr for bioimaging have been successfully established. 相似文献
55.
56.
Emanuela Colombo Rosaria Pascente Daniela Triolo Claudia Bassani Anthea De Angelis Francesca Ruffini Linda Ottoboni Giancarlo Comi Gianvito Martino Cinthia Farina 《Molecules (Basel, Switzerland)》2020,25(22)
Astrocytes greatly participate to inflammatory and neurotoxic reactions occurring in neurodegenerative diseases and are valuable pharmacological targets to support neuroprotection. Here we used human astrocytes generated from reprogrammed fibroblasts as a cellular model to study the effect of the compound Laquinimod and its active metabolite de-Laquinimod on astrocyte functions and the astrocyte–neuron interaction. We show that human iAstrocytes expressed the receptor for the inflammatory mediator IL1 and responded to it via nuclear translocation of NFκB, an event that did not occur if cells were treated with Laquinimod, indicating a direct anti-inflammatory activity of the drug on the human astrocyte. Similarly, while exposure to IL1 downregulated glial glutamate transporters GLAST and GLT1, treatment with Laquinimod supported maintenance of physiological levels of these proteins despite the inflammatory milieu. Laquinimod also induced nuclear translocation of the aryl hydrocarbon receptor (AHR), suggesting that drug action was mediated by activation of the AHR pathway. However, the drug was effective despite AHR inhibition via CH223191, indicating that AHR signaling in the astrocyte is dispensable for drug responses. Finally, in vitro experiments with rat spinal neurons showed that laquinimod did not exert neuroprotection directly on the neuron but dampened astrocyte-induced neurodegeneration. Our findings indicate that fibroblast-derived human astrocytes represent a suitable model to study astrocyte–neuron crosstalk and demonstrate indirect, partial neuroprotective efficacy for laquinimod. 相似文献
57.
A. Akindinov A. Alici P. Antonioli S. Arcelli M. Basile F. Bellini D. Caffarri G. Cara Romeo L. Cifarelli F. Cindolo A. De Caro D. De Gruttola S. De Pasquale K. Doroud M. Fusco Girard B. Guerzoni D. Hatzifotiadou W. W. Jung D. W. Kim J. S. Kim S. Kiselev G. Laurenti K. Lee S. C. Lee D. Malkevich A. Margotti R. Nania A. Nedosekin F. Noferini P. Pagano A. Pesci O. Pinazza R. Preghenella M. Ryabinin E. Scapparone G. Scioli J. Seo A. Silenzi K. Voloshin M. C. S. Williams C. Zampolli A. Zichichi 《The European Physical Journal C - Particles and Fields》2010,68(3-4):601-607
The Time-Of-Flight detector (TOF) of the ALICE experiment at the CERN LHC is based on Multi-gap Resistive Plate Chambers (MRPCs). The TOF detector consists of 152928 readout channels covering a total area of 141 m2. In this paper the results of the calibration with cosmic-ray data collected during 2009 are presented. 相似文献
58.
Maura Pellei Carlo Santini Giancarlo Gioia Lobbia Franco Cantalamessa Cinzia Nasuti Mariacristina Di Prinzio Rosita Gabbianelli Giancarlo Falcioni 《应用有机金属化学》2005,19(5):583-589
New organotin(IV) derivatives containing the anionic ligands bis(3,5‐dimethylpyrazol‐1‐yl)dithioacetate [LCS2]− and bis(3,5‐dimethylpyrazol‐1‐yl)acetate [LCO2]− have been synthesized from reaction between (CH3)2SnCl2 and lithium salts of the ligands. Mononuclear complexes of the type {[LCX2](CH3)2SnCl} (X = S or O) have been obtained and fully characterized by elemental analyses and FT‐IR in the solid state and by NMR (1H, 13C and 119Sn) spectroscopy, conductivity measurements and electrospray ionization mass spectrometry in solution. The acute toxicity of new organotin(IV) derivatives on rat was studied, comparing their effect with those of dimethyltin chloride (CH3)2SnCl2. The comparison of LD50 of organotin(IV) complexes and (CH3)2SnCl2 administered intraperitoneally, as a single dose, evaluated in vivo on rats, showed that toxicity decreases as follows: (CH3)2SnCl2 > LCO2 > LCS2. The effect of these organotin(IV) complexes on DNA was evaluated in vitro and in vivo on rats treated with different doses of these compounds (1/20 LD50 and 1/100 LD50). The lymphocyte DNA status was assessed by the comet assay, a rapid and sensitive single‐cell electrophoresis technique, used to detect primary DNA damage in individual cells. After 36 h from the start of treatment the two new organotin(IV) derivatives induced a significant rise in comet assay parameters, indicating an increasing presence of damaged DNA. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
59.
Hierarchical Analysis of Self‐Assembled PEGylated Hexaphenylalanine Photoluminescent Nanostructures 下载免费PDF全文
Dr. Carlo Diaferia Dr. Teresa Sibillano Dr. Nicole Balasco Dr. Cinzia Giannini Dr. Valentina Roviello Dr. Luigi Vitagliano Prof. Giancarlo Morelli Dr. Antonella Accardo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(46):16586-16597
Despite the growing literature about diphenylalanine‐based peptide materials, it still remains a challenge to delineate the theoretical insight into peptide nanostructure formation and the structural features that could permit materials with enhanced properties to be engineered. Herein, we report the synthesis of a novel peptide building block composed of six phenylalanine residues and eight PEG units, PEG8‐F6. This aromatic peptide self‐assembles in water in stable and well‐ordered nanostructures with optoelectronic properties. A variety of techniques, such as fluorescence, FTIR, CD, DLS, SEM, SAXS, and WAXS allowed us to correlate the photoluminescence properties of the self‐assembled nanostructures with the structural organization of the peptide building block at the micro‐ and nanoscale. Finally, a model of hexaphenylalanine in aqueous solution by molecular dynamics simulations is presented to suggest structural and energetic factors controlling the formation of nanostructures. 相似文献
60.
Francesco Trotta Luisa Costa Giancarlo Costa 《Journal of inclusion phenomena and macrocyclic chemistry》2002,44(1-4):341-344
Optically pure binaphthyl structures make up the most important family of auxiliaries, ligands and catalysts used in enantioselective reactions. Syntheses of 2,2'-disubstituted-1,1'-binaphtyl derivatives were carried out one pot in water by oxidative coupling with FeCl3 in the presence of - and -cyclodextrin (CD) derivatives. A new efficient and inexpensive preparation of trihydroxyethyl- and tri-2-hydroxypropyl- - and -CD afforded these powerful solubilizing agents. The resolution of racemic 2,2'-dihydroxy-1,1'-binaphthyl was easily achieved by semipreparative HPLC separating diastereomers obtained from the reaction with (-)menthyl chloroformate. Final basic hydrolysis afforded the enantiomerically pure product. 相似文献