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91.
Deacon GB Forsyth CM Behrsing T Konstas K Forsyth M 《Chemical communications (Cambridge, England)》2002,(23):2820-2821
The syntheses and structures of the novel Ce-Fe bimetallic complexes [[Fe(sal)2(bpy)]2Ce(NO3)(H2O)3].EtOH and [[Fe(sal)2(bpy)]4Ce2(H2O)11][salH]2.EtOH.3H2O (salH2 = salicylic acid) suggest Fe(3+)-sal2- units and Ce-OC(R)O-Fe bridging contribute to the formation of corrosion inhibitive layers on steel surfaces exposed to [Ce(salH)3(H2O)]. 相似文献
92.
The φ meson productions in Au+Au and/or Pb+Pb collisions at AGS, SPS,
RHIC, and LHC energies have been studied systematically with a hadron and
string cascade model LUCIAE. After considering the energy dependence of the
model parameter α in string fragmentation function and adjusting it
to the experimental data of charged multiplicity to a certain extent,
the model predictions for φ meson yield, rapidity, and
transverse mass distributions are compatible with the experimental data at
AGS, SPS and RHIC energies. A calculation for Pb+Pb collisions at LHC energy
is given as well. The obtained fractional variable in string fragmentation
function shows a saturation in energy dependence. It is discussed that the
saturation of fractional variable in string fragmentation function might be a
qualitative representation of the energy dependence of nuclear transparency. 相似文献
93.
The energy and centrality dependencies of charged particle pseudorapidity density in relativistic nuclearcollisions were studied using a hadron and string cascade model, JPCIAE. Both the relativistic p+p experimental dataand the PHOBOS and PHENIX Au+Au data at RHIC energy could be fairly reproduced within the framework ofJPCIAE model and without retuning the model parameters. The predictions for Pb + Pb collisions at the LHC energywere also given. We computed the participant nucleon distributions using different methods. It was found that thenumber of participant nucleons is not a well defined variable both experimentally and theoretically. Thus it may beinappropriate to use the charged particle pseudorapidity density per participant pair .as a function of the number ofparticipant nucleons for distinguishing various theoretical models. 相似文献
94.
95.
96.
GUY BOUCHITTÉ IRENE FONSECA GIOVANNI LEONI LUÍSA MASCARENHAS 《Archive for Rational Mechanics and Analysis》2002,165(3):187-242
An integral representation formula for a class of functionals defined on and in (the space of special functions of bounded variation) is obtained without requiring the regularity conditions usually imposed
in the literature. The approach is based on the general results of [10] and on a Poincaré-Wirtinger type inequality introduced
by DE GIORGI, CARRIERO & LEACI [25]. Applications to relaxation problems and dimension-reduction problems in brittle thin
films are presented.
(Accepted May 8, 2002) Published online October 18, 2002
Communicated by L. Ambrosio 相似文献
97.
用酶促聚合和原子转移自由基聚合相结合的"一锅法"合成了聚甲基丙烯酸正丁酯嵌段聚10-羟基癸酸[PBMA-b-P(10-HD)],通过核磁共振(1H NMR)、傅里叶红外光谱(FTIR)和凝胶渗透色谱(GPC)对其结构以及分子量与其分子量分布进行了表征,并通过动态光散射仪(DLS)和原子力显微镜(AFM)对聚合物在水溶液中的性质进行了研究.所得嵌段聚合物纳米粒子呈球形结构,平均直径为135 nm左右. 相似文献
98.
99.
Prof. Dr. Marcus L. Cole Prof. Dr. Glen B. Deacon Dr. Craig M. Forsyth Prof. Dr. Peter C. Junk Dr. Kristina Konstas Dr. Jun Wang Henry Bittig Daniel Werner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(4):1410-1420
New reactive, divalent lanthanoid formamidinates [Yb(Form)2(thf)2] (Form=[RNCHNR]; R=o‐MeC6H4 (o‐TolForm; 1 ), 2,6‐Me2C6H3 (XylForm; 2 ), 2,4,6‐Me3C6H2 (MesForm; 3 ), 2,6‐Et2C6H3 (EtForm; 4 ), o‐PhC6H4 (o‐PhPhForm; 5 ), 2,6‐iPr2C6H3 (DippForm; 6 ), o‐HC6F4 (TFForm; 7 )) and [Eu(DippForm)2(thf)2] ( 8 ) have been prepared by redox transmetallation/protolysis reactions between an excess of a lanthanoid metal, Hg(C6F5)2 and the corresponding formamidine (HForm). X‐ray crystal structures of 2 – 6 and 8 show them to be monomeric with six‐coordinate lanthanoid atoms, chelating N,N′‐Form ligands and cis‐thf donors. However, [Yb(TFForm)2(thf)2] ( 7 ) crystallizes from THF as [Yb(TFForm)2(thf)3] ( 7 a ), in which ytterbium is seven coordinate and the thf ligands are “pseudo‐meridional”. Representative complexes undergo C? X (X=F, Cl, Br) activation reactions with perfluorodecalin, hexachloroethane or 1,2‐dichloroethane, and 1‐bromo‐2,3,4,5‐tetrafluorobenzene, giving [Yb(EtForm)2F]2 ( 9) , [Yb(o‐PhPhForm)2F]2 ( 10) , [Yb(o‐PhPhForm)2Cl(thf)2] ( 11) , [Yb(DippForm)2Cl(thf)] ( 12) and [Yb(DippForm)2Br(thf)] ( 16) . X‐ray crystallography has shown 9 to be a six‐coordinate, fluoride‐bridged dimer, 12 and 16 to be six‐coordinate monomers with the halide and thf ligands cis to each other, and 11 to have a seven‐coordinate Yb atom with “pseudo‐meridional” unidentate ligands and thf donors cis to each other. The analogous terbium compound [Tb(DippForm)2Cl(thf)2] ( 13 ), prepared by metathesis, has a similar structure to 11 . C? Br activation also accompanies the redox transmetallation/protolysis reactions between La, Nd or Yb metals, Hg(2‐BrC6F4)2, and HDippForm, yielding [Ln(DippForm)2Br(thf)] complexes (Ln=La ( 14 ), Nd ( 15 ), Yb ( 16 )). 相似文献
100.
Daisuke Sawada Yoshiharu Nishiyama Loukas Petridis R. Parthasarathi S. Gnanakaran V. Trevor Forsyth Masahisa Wada Paul Langan 《Cellulose (London, England)》2013,20(4):1563-1571
The neutron structure of a complex of EDA with cellulose has been determined to reveal the location of hydrogen atoms involved in hydrogen-bonding. EDA disrupts the hydrogen-bonding pattern of naturally occurring cellulose by accepting a strong hydrogen-bond from the O6 hydroxymethyl group as the conformation of this group is rotated from tg to gt. The O3-H·O5 intrachain hydrogen-bond commonly found in cellulose allomorphs is observed to be disordered in the neutron structure, and quantum chemistry and molecular dynamics calculations show that O3 prefers to donate to EDA. The hydrogen-bonding arrangement is highly dynamic with bonds continually being formed and broken thus explaining the difficulty in locating all of the hydrogen atoms in the neutron scattering density maps. Comparison with other polysaccharide-amino complexes supports a common underlying mechanism for amine disruption of cellulose. 相似文献