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31.
D. Seweryniak B. Cederwall J. Nyberg C. Fahlander A. Johnson A. Kerek J. Kownacki L. -O. Norlin E. Adamides A. Atac J. Blomqvist H. Grawe E. Ideguchi R. Julin S. Juutinen W. Karczmarczyk S. Mitarai M. Piiparinen R. Schubart G. Sletten S. Törmänen A. Virtanen 《Zeitschrift für Physik A Hadrons and Nuclei》1993,345(2):243-244
Neutron deficient nuclei close to 100Snhave been investigated in-beam by γ-ray spectroscopic methods using the NORDBALL detector array. A beam of 270 MeV 58Niwas used to bombard a target of 54Fe.Reaction channel separation was achieved with a 4π charged particle multidetector setup together with a 1π neutron detector wall placed in the forward direction. Excited states of 102Inwere identified for the first time. The level scheme constructed from γ-γ-particle-coincidence and γ-γ-angular correlation analysis is presented. The structure of 102 In is discussed and compared to neighboring nuclei in the framework of the nuclear shell-model. 相似文献
32.
A. Neskakis R. M. Lieder H. Beuscher B. Bochev D. Haenni M. Müller-Veggian G. Sletten 《Zeitschrift für Physik A Hadrons and Nuclei》1982,304(3):277-278
Bands in 180 Os have been studied with in-beam spectroscopy methods. Four side bands were established. Configurations have been assigned to them considering the features of similar bands in neighbouring nuclei. New aspects result from an interpretation in the framework of the cranked shell model. 相似文献
33.
A subnanosecond fission isomer has been found in 238Pu by means of a new fission-inflight technique. An isomer with a longer half-life reported previously in the same nucleus has been detected simultaneously. The half-lives are 0.5 ± 0.2 ns and 5 ± 2 ns respectively. Excitation functions show that the two isomers are separated by 1.3 ± 0.3 MeV, the short-lived isomer having the lowest excitation energy. It is assigned as the ground state while the 5 ns state is interpreted as a quasiparticle state in the second potential well. The difference of 1.3 MeV in excitation energy defines within the uncertainty the neutron energy gap at the isomeric deformation. 相似文献
34.
Perru O Sorlin O Franchoo S Azaiez F Bouchez E Bourgeois C Chatillon A Daugas JM Dlouhy Z Dombrádi Z Donzaud C Gaudefroy L Grawe H Grévy S Guillemaud-Mueller D Hammache F Ibrahim F Le Coz Y Lukyanov SM Matea I Mrazek J Nowacki F Penionzhkevich YE de Oliveira Santos F Pougheon F Saint-Laurent MG Sletten G Stanoiu M Stodel C Theisen Ch Verney D 《Physical review letters》2006,96(23):232501
The reduced transition probabilities B(E2;0(+) --> 2(+)(1)) of the neutron-rich (74)Zn and (70)Ni nuclei have been measured by Coulomb excitation in a (208)Pb target at intermediate energy. These nuclei have been produced at Grand Accélérateur National d'Ions Lourds via interactions of a 60A MeV (76)Ge beam with a Be target. The B(E2) value for (70)Ni(42) is unexpectedly large, which indicates that neutrons added above N=40 strongly polarize the Z=28 proton core. In the Zn isotopic chain, the steep rise of B(E2) values beyond N=40 continues up to (74)Zn(44). The enhanced proton core polarization in (70)Ni is attributed to the monopole interaction between the neutron in the g(9/2) and protons in the f(7/2) and f(5/2) spin-orbit partner orbitals. This interaction could result in a weakening of magicity in (78)Ni(50). 相似文献
35.
L. Nagy A. Szorcsik H. Jankovics T. Yamaguchi K. Yoshida M. Scopelliti L. Pellerito E. Sletten 《Journal of Radioanalytical and Nuclear Chemistry》2008,275(1):193-200
Complexes of adenosine and related compounds (adenosine-5’-monophosphate, adenosine-5’-triphosphate and pyridoxal-5-phosphate) with Bu2SnO and/or BuSnCl2 were prepared in the solid state. The compositions of the complexes were determined by standard analytical methods. It was found that the complexes contain the organotin(IV) moiety and the ligand in a ratio of 1:1. The FT-IR spectra demonstrated that Bu2SnO reacts with the D-ribose moiety of the ligands, while Bu2SnCl2 is coordinated to the deprotonated phosphate group. The basic part of the ligands does not participate directly in complex formation. Comparison of the experimental Mössbauer Δ (quadrupole splitting) values with those calculated on the basis of the pqs concept revealed that the organotin(IV) moiety has Tbp and in some cases also Th geometry. The adenosine complex contains the organotin(IV) cation in two different surroundings (Tbp and Th). The local structures of the complexes were determined by means of EXAFS measurements. At the same time a number of organotin(IV) complexes containing different organo moieties of calf thymus DNA were also prepared. Similarly as above, EXAFS data were obtained for these compounds and analyzed by using multishell models up to 300 pm. These results are the first structural data (bond lengths) on complexes formed with organotin(IV)-DNA and related compounds. 相似文献
36.
A tetracationic supramolecular helicate, [Fe2L3]4+ (L = C25H20N4), with a triple-helical architecture is found to induce the formation of a three-way junction (3WJ) of deoxyribonucleotides with the helicate located in the center of the junction. NMR spectroscopic studies of the interaction between the M enantiomer of the helicate and two different oligonucleotides, [5'-d(TATGGTACCATA)]2 and [5'-d(CGTACG)]2, show that, in each case, the 2-fold symmetry of the helicate is lifted, while the 3-fold symmetry around the helicate axis is retained. The 1:3 helicate/DNA stoichiometry estimated from 1D NMR spectra supports a molecular model of a three-way junction composed of three strands. Three separate double-helical arms of the three-way junction are chemically identical giving rise to one set of proton resonances. The NOE contacts between the helicate and DNA unambiguously show that the helicate is fitted into the center of the three-way junction experiencing a hydrophobic 3-fold symmetric environment. Close stacking interactions between the ligand phenyl groups and the nucleotide bases are demonstrated through unusually large downfield shifts (1-2 ppm) of the phenyl protons. The unprecedented 3WJ arrangement observed in solution has also been found to exist in the crystal structure of the helicate adduct of [d(CGTACG)2] (Angew. Chem., Int. Ed. 2006, 45, 1227). 相似文献
37.
K. Jessen W. Andrejtscheff M. Bergström P. von Brentano A. Dewald B. Herskind H. Meise C. Schumacher G. Sletten O. Stuch D. Weißhaar I. Wiedenhöver J. Wrzesinski 《The European Physical Journal A - Hadrons and Nuclei》1999,4(1):9-10
A new high-spin isomer in 145Sm was observed by in-beam γ-ray spectroscopy with the reaction 122Sn(27Al,3np) at 127 MeV performed at the Nordball multi-detector array in Roskilde. The excitation energy of the isomer was determined
to be E
x= 11147 keV, and using the generalized centroid-shift method its half-life was found to be T
1/2= (7.4 ± 1.0) ns.
Received: 23 October 1998 相似文献
38.
J. Domscheit S. Trmnen B. Aengenvoort H. Hübel R. A. Bark M. Bergstrm A. Bracco R. Chapman D. M. Cullen C. Fahlander S. Frattini A. Grgen G. B. Hagemann A. Harsmann B. Herskind H. J. Jensen S. L. King S. Lenzi D. Napoli S. W.
degrd C. M. Petrache H. Ryde U. J. van Severen G. Sletten P. O. Tjm C. Ur 《Nuclear Physics A》1999,660(4):1211-392
High-spin states in 163Lu have been investigated using the Euroball spectrometer array. The previously known superdeformed band has been extended at low and high energies, and its connection to the normal-deformed states has been established. From its decay the mixing amplitude and interaction strength between superdeformed and normal states are derived. In addition, a new band with a similar dynamic moment of inertia has been found. The experimental results are compared to cranking calculations which suggest that the superdeformed bands in this mass region correspond to shapes with a pronounced triaxiality (γ≈±20°). 相似文献
39.
Stéphane Téletchéa Dr. Tormod Skauge Dr. Einar Sletten Prof. Jiří Kozelka Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(45):12320-12337
The antitumor drug cisplatin (cis‐[PtCl2(NH3)2]) reacts with cellular DNA to form GG intrastrand adducts between adjacent guanines as predominant lesions. GGG sites have been shown to be hotspots of platination. To study the structural perturbation induced by binding of cisplatin to two adjacent guanines of a GGG trinucleotide, we examined here the decanucleotide duplex d[(G1C2C3 G6T7‐ C8G9C10) ? d(G11C12G13A14C15C16C17G18‐ G19C20)] ( dsCG*G*G ) intrastrand cross‐linked at the G* guanines by cis‐{Pt(NH3)2}2+ using NMR spectroscopy and molecular dynamics (MD) simulations. The NMR spectra of dsCG*G*G were found to be similar to those of previously characterized DNA duplexes cross‐linked by cisplatin at a pyG*G*X site (py=pyrimidine; X=C, T, A). This similarity of NMR spectra indicates that the base at the 3′‐side of the G*G*–Pt cross‐link does not affect the structure to a large extent. An unprecedented reversible isomerization between the duplex dsCG*G*G (bearing a –Pt chelate) and duplex dsGG*G*T (bearing a –Pt chelate) was observed, which yielded a 40:60 equilibrium between the two intrastrand GG–Pt cross‐links. No formation of interstrand cross‐links was observed. NMR spectroscopic data of dsCG*G*G indicated that the deoxyribose of the 5′‐G* adopts an N‐type conformation, and the cytidines C3, C15, and C16 have average phase angles intermediate between S and N. The NMR spectroscopic chemical shifts of dsGG*G*T showed some fundamental differences to those of pyG*G*–platinum adducts but were in agreement with the NMR spectra reported previously for the DNA duplexes cross‐linked at an AG*G*C sequence by cisplatin or oxaliplatin. The presence of a purine instead of a pyrimidine at the 5′‐side of the G*G* cross‐link seems therefore to affect the structure of the XG* step significantly. 相似文献
40.
K. Jessen M. Bergström P. von Brentano A. Dewald B. Herskind H. Meise C. Schumacher G. Sletten O. Stuck D. Weißhaar I. Wiedenhöver J. Wrzesinski 《The European Physical Journal A - Hadrons and Nuclei》1998,2(2):113-114
An in-beam experiment with the reaction 122Sn(27Al,4np) at 127 MeV was performed at the Nordball multi-detector array in Roskilde. It provided evidence for a new high-spin
isomer in 144Sm. This isomer with T
1/2= (2.6 ± 0.5) ns at an excitation energy E
x= 9232 keV seems to belong to a family of isomers of similar configuration in neighbouring N= 82 nuclei.
Received: 16 November 1997 相似文献