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151.
152.
Dragana TadicJoannes T.M Linders Judith L Flippen-Anderson Arthur E JacobsonKenner C Rice 《Tetrahedron》2003,59(25):4603-4614
Two of the 12 possible oxide-bridged phenylmorphans, were synthesized, rac-(3R,6aS,11aS)-2-methyl-1,3,4,5,6,11a-hexahydro-2H-3,6a-methanobenzofuro[2,3-c]azocine-10-ol (7) (the ortho-c compound), and rac-(3R,6aS,11aS)-2-methyl-1,3,4,5,6,11a-hexahydro-2H-3,6a-methanobenzofuro[2,3-c]azocine-8-ol (8) (the para-c compound). Single-crystal X-ray diffraction studies indicated that the dihedral angle between the least squares planes through the phenyl ring and the atoms C1, C11a, C12, and C3 in the piperidine ring in both 7·CHCl3 and 8·HBr was 6.9°. The C12-C6a-C6b-C10a torsion angle was found to be 139.3° for both compounds. The angular relationship between the phenolic ring and the piperidine ring in phenylmorphans that interact with specific opioid receptors as agonists or antagonists is of considerable theoretical interest. 相似文献
153.
Brigitte BibalJean-Paul Declercq Jean-Pierre Dutasta Bernard TinantAnne-Gaëlle Valade 《Tetrahedron》2003,59(31):5849-5854
The iiii stereoisomer of the tetrathiophosphonate-calix[4]resorcinarene host 1 exhibited excellent extraction properties towards soft metal ions, with a better affinity for Ag+ (91%), than for Tl+ (38%) and Hg2+ (16%). The extraction of other picrate salts (Cu2+, Ni2+, Co2+, Zn2+, Cd2+, Pb2+) was not detected. The stoichiometry and the structure of the Hg2+, Tl+ and Ag+ complexes were studied by NMR in solution and gave respectively 1:1, 1:1 and 1:2 host-guest complexes. The formation of the self-assembled 12·(AgPic)4 complex was independent on the anion and only observed with silver(I) ion. 相似文献
154.
The carbamoyl methyl sulfoxide compounds of uranyl bis(β-diketonate) of the types [UO2(DBM)2CMSO] and [{UO2(DBM)2}2CMSO] (where HDBM = C6H5COCH2COC6H5; CMSO = C6H5CH2SOCH2CONHC6H5 or C6H5SOCH2CONiPr2) have been synthesized and characterized by IR and NMR spectroscopic techniques and elemental analysis. Spectral studies show that CMSO acts as a monodentate ligand in [UO2(DBM)2CMSO] compounds and bonds through the sulfoxo oxygen atom to the uranyl group. It acts as a bridging bidentate ligand in [{UO2(DBM)2}2CMSO] compounds and bonds through both the sulfoxo and carbamoyl oxygen atoms to two different uranyl groups. The structure of the compound [{UO2(DBM)2}2C6H5CH2SOCH2CONHC6H5] confirms the bridging bidentate mode of coordination for the CMSO ligand. Extraction studies show an enhancement in solvent extraction for the uranyl ion from nitric acid medium when a mixture of thenoyl trifluoroacetone (HTTA) and CMSO was employed. 相似文献
155.
运用三足四齿配体三(2-甲基吡啶)胺(TPA)或三(2-甲基苯丙咪唑)胺(TBA),得到两个双核铁(III)配合物,[Fe2L2(μ2-O)(μ2-p-NH2-C6H4COO)]3+
(L = TPA, 1 和 L = TBA,
2)。两个配合物均为单斜晶系,空间群为P2(1)/c.晶胞参数 1: a =
1.4529(4), b = 1.6622(5), c = 2.0625(6) nm, β= 100.327(5)º,
V = 4.900(3) nm3, z = 4, F(000) = 2344, 分子量Mr = 1142.91, Dc
= 1.549 g/cm3, R1 = 0.0544,
R2 = 0.0962. 2: a = 1.3378(4), b = 2.1174(7), c =
2.4351(7) nm, β= 97.315(6)º, V = 6.842(4) nm3,
z = 4, F (000) = 3116, 分子量Mr = 1505.08, Dc
= 1.444 g/cm3, R1 = 0.0793, R2 = 0.1623. 在两个双核铁(III)配合物中,中心的三价铁和配体TPA或TBA上的四个氮原子和两个氧原子通过不同的桥形成一个畸变的八面体构型。 相似文献
156.
The title coordination compound with N-substituted-salicyl Schiff ligand, Cu(C15H12N2O3)(C5H5N), has been synthesized. The coordination compound crystallizes in orthorhombic system, space group Pbca with a=2.037 62(7) nm, b=0.698 45(2)nm, c=2.508 76(9)nm, V=3.570 4(2) nm3, Z=8, F(000)=1 688, Dc=1.529 g·cm-3, Mr=410.91, μ=1.250 mm-1, R=0.031 3 and wR=0.077 0. In the coordination compound, one phenolate oxygen, one carbonyl oxygen and one hydrazine nitrogen atom from the dianionic ligand N-salicylaldehyde-N′-(4-methoxybenzoyl) hydrazone and one pyridine nitrogen atom coordinate to Cu(Ⅱ) ion, forming a distorted square plane. CCDC: 218182. 相似文献
157.
O. A. Kizas V. V. Krivykh V. V. Vorontsov A. A. Koridze 《Russian Chemical Bulletin》1993,42(6):1102-1103
Protonation of triosmium clusters Os3(-H)(CO)9(3-,2-CC-R) (R=CMe2OH, C(Me)=CH2) affords a cationic complex containing a six-electron propargyl ligand which has been detected for the first time.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1144–1145, June, 1993. 相似文献
158.
Formation contants (log K
MAL
MA
) of mixed ligand complexes MAL, where M = UO
2
2+
or Th4+, A = IMDA, NTA, HEDTA, EDTA, CDTA or DTPA, and L = resorcinol (res), 2-methyl resorcinol (2-Me-res), 5-methyl resorcinol
(5-Me-res) or 4-chloro resorcinol (4-Cl-res), have been determined pH-metrically by the Irving-Rossotti approach at 25°C and
at an ionic strength,I = 0.2(moldm−3KNO3). The observed stability sequences are IMDA > NTA > HEDTA > EDTA > CDTA > DTPA, and 4-Cl-res > 5-Me-res > 2-Me-res > res
with respect to primary and secondary ligands, respectively. Th4+ forms more stable mixed complexes than UO
2
2+
. The A ΔlogK values are negative due mainly to the charge repulsion involved in the complexation MA + L⇋MAL. 相似文献
159.
Surprising Reactions on O-Methyl-1,1-dithiooxalates The O-methyl-1,1-dithiooxalate ligand (i-dtoMe) reacts with metalII-acetylacetonates of d8 metal centers (NiII, PdII) forming mononuclear mixed ligand complexes with two remarkable aspects: The formation of a perthioligand, first time described for thiooxalates, and the first example of a nucleophilic attack of a CH-acidic compound (acetylacetonate) on dithiocarbon of coordinated dithiocompounds (here i-dtoMe). X-ray structure is shown for Ph4P[(ptoMe)Ni(i-dtoMeacac)]. 相似文献
160.
Yi-Chun Lai 《Tetrahedron》2005,61(40):9484-9489
Palladium-catalyzed Suzuki cross-coupling reactions employing Schiff-bases as ligands toward a series of substituted arylbromides and boronic acids were pursued. In the presence of a N,O-bidentate ligand, 2-[1-(2,4,6-trimethyl-phenylimino)-ethyl]-phenol 5, the catalytic reactions could be carried out efficiently at room temperature with a wide array of arylbromides, even with electronically deactivated arenes. A deprotonated 5, 5′, chelated palladium acetate complex, [5′Pd(II)(OAc)(solv)] 8, was proposed as a precursor of a genuine catalytically active species. 相似文献