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21.
LetIP[f(n)] be the class of languages recognized by interactive proofs withf(¦x¦) interactions. Babai [2] showed that all languages recognized by interactive proofs with a bounded number of interactions can be recognized by interactive proofs with only two interactions; i.e., for every constantk, IP[k] collapses toIP[2].In this paper, we give evidence that interactive proofs with an unbounded number of interactions may be more powerful than interactive proofs with a bounded number of interactions. We show that for any polynomially bounded polynomial time computable functionf(n) and anyg(n)=o(f(n)) there exists an oracleB such thatIP
B
[f(n)]
=
IP
B
[g(n)].The techniques employed are extensions of the techniques for proving lower bounds on small depth circuits used in [6], [14] and [10].Research done while in the Department of Mathematics at M. I. T. and supported by an ONR graduate fellowship.Supported in part by NSF Grant DCR MCS8509905.Research done while at the Laboratory for Computer Science at M. I. T. and Supported by an IBM fellowship. 相似文献
22.
In several previous papers we have argued for a global and non-entropic approach to the problem of the arrow of time, according
to which the “arrow” is only a metaphorical way of expressing the geometrical time-asymmetry of the universe. We have also
shown that, under definite conditions, this global time-asymmetry can be transferred to local contexts as an energy flow that
points to the same temporal direction all over the spacetime. The aim of this paper is to complete the global and non-entropic
program by showing that our approach is able to account for irreversible local phenomena, which have been traditionally considered
as the physical origin of the arrow of time. 相似文献
23.
Nadia Manzo Fabiana Pizzolongo Alessandra Aiello Raffaele Romano 《Natural product research》2019,33(13):1835-1841
Heat treatments can cause degradation in tomatoes of lycopene which has important antioxidant effects. No information about decimal reduction time (D100) of lycopene is available. D-value is the time required at a given temperature to reduce 90% of the molecule. This study for the first time determine the kinetic of lycopene thermal degradation. The content was measured at regular intervals of pasteurization using canned tomato paste to determinate D value. Microbiological analysis was carried out to verify product stability after packaging. Yeasts, molds and lactic acid bacteria were determined. The pasteurization time allowed to observe a loss of the red color. Lycopene content, after an increase at 8 min, decreased at 32 min of pasteurization. D100 value was calculated at 75 min; a diminution of 90% in lycopene content in the concentrated tomato paste was observed. Microbiological analysis confirmed the stability of products after 8 min of pasteurization. 相似文献
24.
Fontana A Viale M Guernelli S Gasbarri C Rizzato E Maccagno M Petrillo G Aiello C Ferrini S Spinelli D 《Organic & biomolecular chemistry》2010,8(24):5674-5681
Different nitronaphthylbutadienes have been previously proved to have antitumour activity. The main drawback of these derivatives is their low water solubility. With the aim of facilitating the administration of these new drugs we have synthesized the hexyl (2Z,4E)-2-methylsulfanyl-5-(1-naphthyl)-4-nitro-2,4-pentadienoate analogue (1-Naph-NHCB) which is demonstrated to be easily included into cyclodextrins and/or entrapped into liposomes. Its antitumour activity was revealed to be almost comparable with that of the previously studied methyl analogue ester (1-Naph-NMCB). On the other hand, in vitro studies with different cancer cell lines showed that the cytotoxic activity of both 1-Naph-NMCB and 1-Naph-NHCB were fully preserved and in some cases also enhanced when entrapped into liposomal carriers. 相似文献
25.
Farid Jahouh Rina Saksena Donatella Aiello Anna Napoli Giovanni Sindona Pavol Kováč Joseph H. Banoub 《Journal of mass spectrometry : JMS》2010,45(10):1148-1159
We present the MALDI‐TOF/TOF‐MS analyses of various hapten–bovine serum albumin (BSA) neoglycoconjugates obtained by squaric acid chemistry coupling of the spacer‐equipped, terminal monosaccharide of the O‐specific polysaccharide of Vibrio cholerae O1, serotype Ogawa, to BSA. These analyses allowed not only to calculate the molecular masses of the hapten–BSA neoglycoconjugates with different hapten–BSA ratios (4.3, 6.6 and 13.2) but, more importantly, also to localize the covalent linkages (conjugation sites) between the hapten and the carrier protein. Determination of the site of glycation was based on comparison of the MALDI‐TOF/TOF‐MS analysis of the peptides resulting from the digestion of BSA with similar data resulting from the digestion of BSA glycoconjugates, followed by sequencing by MALDI‐TOF/TOF‐MS/MS of the glycated peptides. The product‐ion scans of the protonated molecules were carried out with a MALDI‐TOF/TOF‐MS/MS tandem mass spectrometer equipped with a high‐collision energy cell. The high‐energy collision‐induced dissociation (CID) spectra afforded product ions formed by fragmentation of the carbohydrate hapten and amino acid sequences conjugated with fragments of the carbohydrate hapten. We were able to identify three conjugation sites on lysine residues (Lys235, Lys437 and Lys455). It was shown that these lysine residues are very reactive and bind lysine specific reagents. We presume that these Lys residues belong to those that are considered to be sterically more accessible on the surface of the tridimensional structure. The identification of the y‐series product ions was very useful for the sequencing of various peptides. The series of a‐ and b‐product ions confirmed the sequence of the conjugated peptides. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
26.
27.
Anna Maria Almerico Girolamo Cirrincione Gaetano Dattolo Enrico Aiello Francesco Mingoia 《Journal of heterocyclic chemistry》1994,31(1):193-198
Acid catalyzed decomposition of the azido derivatives 4a-c gave rise to amino-hydroxy-phenylpyrroles of type 7 and 8 upon hydrolysis of the intermediate aryl nitrenium ions, together with the hydrogen abstraction compounds of type 3 . The aminopyrrolo[1,2-f]phenanthridines 10, 11 , and 12 were obtained by treatment with TFMSA of the azide 4d in which the ring being attacked was made more nucleophilic by the introduction of the methoxy group. 相似文献
28.
S. Plescia G. Daidone V. Sprio E. Aiello G. Dattolo G. Cirrincione 《Journal of heterocyclic chemistry》1978,15(8):1287-1290
Preparation and structural evidence of N-methyl-(1,3-R,R'-pyrazol-5-yl)-o-nitrobenzamides (VIIIa, b) are discussed. Diazotisation of related o-aminobenzamides XIa,b followed by the Pschorr reaction afforded a very complex mixture from which pyrazolo[3,4-c]isoquinolin-5-ones XIIa.b in 7–10% yields together with N-methyl-(1,3-R,R'-pyrazol-5-yl)-o-hydroxybenzamides (XIIIa) in 15–20% yields were isolated. 相似文献
29.
Enrico Aiello Gaetano Dattolo Girolamo Cirrincione Anna Maria Almerico Isabella D'Asdia 《Journal of heterocyclic chemistry》1981,18(6):1153-1155
The synthesis of a new heterocyclic ring system is described. Condensation of 1,4-diketones 1a,b with β-alanine gave the substituted propionic acids 2a,b which upon reduction with palladium on charcoal afforded compounds 3a,b . Title compounds 4a,b were obtained by refluxing 3a,b in toluene with p-toluenesulphonic acid as catalyst. 相似文献
30.
Mauro Ghedini Daniela Pucci Alessandra Crispini Iolinda Aiello Francesco Barigelletti Alessandro Gessi Oriano Francescangeli 《应用有机金属化学》1999,13(8):565-581
The series of dinuclear 4,4′‐bis(hexyloxy)azobenzene, [H(Azo‐6)], cyclopalladated complexes of general formula [Azo‐6)Pd(µ‐X)]2, (X = Cl, Br, I, N3, SCN, OAc) and [Azo‐6)2Pd2(µ‐Ox)] (Ox = oxalate) have been synthesized and investigated for mesomorphism and spectroscopic properties. Single‐crystal X‐ray analysis of the dinuclear bromo‐ and iodo‐bridged complexes has been performed. The structural data, compared with those of the known homologous chloro compound, show that all the [Azo‐6)Pd(µ‐X)]2)] (X = Cl, Br, I) molecules crystallize in the monoclinic space group P21/c and are isomorphous. They are arranged in slipped pairs with intermolecular non‐bonding Pd–Pd contacts ranging from 3.668(1) Å(X = Cl) to 3.758(3) Å(X = I). The different nature of the bridging group allows variation of the distance between the palladium atoms and the bond environment experienced by the metal centers. Thus, this comparative study reveals that the effectiveness of the bridging group in promoting thermotropic mesophases is greater for chloride, bromide, azide or oxalate than for iodide, thiocyanate or acetate. The greatest range of liquid‐crystal behavior was displayed by [Azo−6)2Pd2(µ−Ox)]. Remarkably, this compound is the first example of a metallomesogen containing the bridging oxalate group. The bimetallic complexes exhibit different absorption spectra (i.e. colors) depending, in general terms, on the nature of the bridge connecting the two cyclometalated [H(Azo‐6)] moieties, which can be varied so as to tune the optical properties. Blocking the azo group in the trans position results in several cases in weakly luminescent complexes, with luminescence efficiencies ϕ ≈10−4 and luminescence lifetimes of the order of nanoseconds. Using the data obtained from the 4,4′‐bis(hexyloxy)azoxybenzene [H(Azoxy‐6)] derivative, [Azoxy‐6)Pd(µ<?tf="ps2b61">‐Cl)]2, from the mononuclear acetylacetonate (acac) complexes [(Azo‐6)Pd(acac)] and [(Azoxy‐6)Pd(acac)], and from the uncomplexed [H(Azo‐6)] and [H(Azoxy‐6)] ligands, the nature of the excited states relevant to the photophysical behavior are discussed. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献