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101.
T Matsuo K Uchino T Toukairin M Iwamoto Y Tonosaki T Akiyama H Ogawara A Fukuchi 《Chemical & pharmaceutical bulletin》1989,37(7):1849-1851
New 5'-nucleotidase-inhibitory polyphenols named NPF-86IA, NPF-86IB, NPF-86IIA and NPF-86IIB were isolated from the seeds of Areca catechu L. The ability of the inhibitors to precipitate gelatin was investigated by microturbidimetry. These inhibitors produced weak turbidity. As 5'-nucleotidase is a kind of phosphatase, we examined the effects of these inhibitors on alkaline and acidic phosphatases. While they showed moderate inhibitory effects on the activity of acidic phosphatases, they did not have any significant effect on the activity of alkaline phosphatase. Therefore, they showed a higher inhibitory effect on the 5'-nucleotidase than the other phosphatases, Murine macrophages were directly stimulated by the 5'-nucleotidase inhibitors. 相似文献
102.
Hidetaka Yuge Toschitake Iwamoto 《Journal of inclusion phenomena and macrocyclic chemistry》1996,26(1-3):119-126
The title inclusion compound [{NH2(CH2CH2)2NCH2CH2NH2}2H][Cu4(CN)7] was obtained as single crystals from an aqueous solution containing CuCN, KCN, andN-(2-aminoethyl)piperazine. It crystallizes in the monoclinic space groupP2/n,a = 12.3829(9),b = 8.5970(9),c = 12.6633(7) Å, = 109.984(5)°,z = 2,R = 0.035 for 2921 independent reflections. The inclusion structure is composed of the hydrogen-bonded dimeric onium guest [{NH2(CH2CH2)2NCH2CH2NH2}2H]3+ and the negatively-charged three-dimensional host [CU4(CN)7]3– in which the CN-bridged framework Cu(I) atoms are all tetrahedral. A polyacene-like one-dimensional array of hexagons cornered by Cu(I) atoms and edged by -CN- linkages is arrayed in parallel to theb axis and stacked approximately along the c axis. The Cu(I) corner shared in the one-dimensional array extends an N-coordinate CN group along the c axis to a pair of unshared Cu(I) corners for which the C end behaves as a bifurcated ligand to build up the three-dimensional host structure. The cavity is composed of two networks of the hexagons at the top and bottom and pillared by six >CN- groups and accommodates a dimeric guest ofN-(2-aminoethyl)piperazinium cations protonated at each 4-N with the cations being hydrogen-bonded to each other through the 2-NH2 groups sharing another H+.Presented at the Sixth International Seminar on Inclusion Compounds, Istanbul, Turkey, 27–31 August, 1995. 相似文献
103.
Tai Hasegawa Toschitake Iwamoto 《Journal of inclusion phenomena and macrocyclic chemistry》1988,6(2):143-156
The crystal structures of the four title compounds have been analyzed by single crystal X-ray diffraction methods at room temperature. Three with a general formula Cd[NH2(CH2)6NH2]Ni(CN)4·G (G=m-toluidine,Im;p-toluidine,Ip; and 2,4-xylidine,Ix) are the inclusion compounds of the respective aromatic molecules in the three-dimensional metal complex host (1,6-diaminohexane)cadmium(II) tetracyanonickelate(II). The remaining one is a coordination complex ofp-toluidine, bis(p-toluidine) (1,6-diaminohexane)cadmium(II) tetracyanonick-elate(II),II, Im, Ix, andII crystallize under similar experimental conditions;Ip is obtained using thep-toluidinemesitylene mixture at higher dilution than that used forII. Im crystallizes in the tri linic space group \(P\bar 1\) , witha=9.725(2),b=7.598(1),c=7.177(1) Å, α=90.44(1), β=98.80(1), γ=95.70(1)o, andZ=1 (the final conventionalR=0.037 for 3526 reflections);Ip: monoclinic,P2/m,a=9.540(2),b=7.611(1),c=7.120(1) Å, β=100.95(1)o, andZ=1 (R=0.027 for 1700 reflections);Ix: monoclinic,P2/m,a=9.628(2),b=7.613(1),c=7.122(1) Å, β=100.01(1)o, andZ=1 (R=0.049 for 2704 reflections);II: monoclinic,P21/n,a=12.107(3),b=10.117(2),c=12.471(3) Å, β=113.67(2)o, andZ=2 (R=0.037 for 2616 reflections). The structures ofIm, Ip andIx are similar to that of theo-toluidine inclusion compound of the same metal complex host. InII atrans pair of thep-toluidine molecules to the cadmium atom in the two-dimensional network formed by thecatena-μ-linkages of ?Cd?NH2(CH2)6NH2?Cd? and ?NC?Ni?CN?Cd?NC?Ni?CN?intersecting at each Cd atom; two cyanide groups of the tetracyanonickelate(II) moiety have free N-ends. 相似文献
104.
Masakazu Iwamoto Shin-Ichiro Nakamura Hideto Kusano Shuichi Kagawa 《Journal of inclusion phenomena and macrocyclic chemistry》1986,4(1):99-103
The adsorption and/or decomposition pathway of Fe2(CO)9 or Fe3(CO)12 on hydrated or dehydrated NaY zeolites has been studied by an ESR technique. The adsorption resulted in the formation of three paramagnetic species withg
iso=2.0450, 2.0378, and 2.0016, which were attributable to Fe3(CO)11
–, Fe2(CO)8
–, and Fe(CO)4
– anion radicals, respectively. These radicals have been suggested as intermediates in the formation of HFe3(CO)11
– on the hydrated NaY zeolite and Fe3(CO)12 on the dehydrated NaY zeolite. 相似文献
105.
The growth inhibition of Streptococcus mutans by 5'-nucleotidase inhibitors from Areca catechu L 总被引:4,自引:0,他引:4
M Iwamoto K Uchino T Toukairin K Kawaguchi T Tatebayashi H Ogawara Y Tonosaki 《Chemical & pharmaceutical bulletin》1991,39(5):1323-1324
New 5'-nucleotidase inhibitors named NF-86I, NF-86II were recently isolated from the seeds of Areca catechu L. NF-86I and NF86II showed inhibitory effects on the growth of Streptococcus mutans MT8148(c) and Streptococcus mutans MT6715(g), respectively. In addition, these inhibitors could inhibit insoluble glucan formation from sucrose. NF-86I and NF-86II were found to be polyphenolic substances. Some polyphenols such as tannic acid bind non-specifically to proteins (tannic activity). The 5'-nucleotidase inhibitors that we isolated did not show any such activity. However, the growth inhibitory activity and the inhibitory effect on water-insoluble glucan production were equal to tannic acid. It is therefore considered that these inhibitors bind specifically to the bacterial cell surface. Our findings suggest that the 5'-nucleotidase inhibitors NF-86I and NF-86II may be useful anti-plaque preventing agents. 相似文献
106.
A new simple model of porphyrin ring current effect was proposed based on a line current approximation. It can reproduce the porphyrin-induced shifts for several Sn(IV)(tpp) and Sn(IV)(oep) dicarboxylate complexes quite satisfactorily. Perpendicular arrangement of the aromatic rings in the diaromatic-carboxylate complexes of Sn(IV)(tpp) and Sn(IV)(oep) was clarified with this porphyrin ring current effect model. There are two structures, exo and endo, in solution in dinaphthalene-1- and 2- carboxylate complexes of Sn(IV)(tpp) and Sn(IV)(oep). The exo conformer is in dynamic equilibrium with the endo form in solution. Thermodynamic data of these conformational equilibria are given. 相似文献
107.
M. SenŌ H. Noritomi Y. Kuroyanagi K. Iwamoto G. Ebert 《Colloid and polymer science》1984,262(11):896-901
The molecular conformations of poly(N5-dihydroxyethylaminopropyl-L-glutamine) and poly(N5-dihydroxyethyl-L-glutamine) were investigated in reversed micelles of AOT as well as in aqueous solutions. Both poly(-amino acid)s assume disordered structures in pure water. The conformation of poly(N5-dihydroxyethylaminopropyl-L-glutamine) transits into-helix in the reversed micelles as the molar ratio of water to AOT (w0=[H2O]/[AOT]) becomes smaller. A similar conformational transition was also observed in aqueous solutions when a certain amount of AOT was added. Under these conditions, however, poly(N5-dihydroxyethyl-L-glutamine) did not undergo a conformational transition into-helix. 相似文献
108.
T Morita Y Iwamoto T Shimizu T Masuzawa Y Yanagihara 《Chemical & pharmaceutical bulletin》1989,37(2):407-409
The mutagenicity (Trp+ reversion) of procarcinogens such as N-nitrosodimethylamine, 3,4-benzpyrene and 2-acetylaminofluorene has been detected with the permeable mutant of yeast, Saccharomyces cerevisiae C658-K42. The original strain C658, however, showed a positive response only to N-nitrosodimethylamine with S9 mix. The permeable mutant C658-K42 was employed for mutagenicity tests on 12 carcinogens which had been reported to be non-mutagenic in Salmonella/microsome tests. It was found that phenobarbital, thiourea, 1,2-dimethylhydrazine and 4-aminoantipyrine were mutagenic in the presence of S9 mix. Benzene, o-toluidine and thioacetamide were weakly mutagenic. Negative results were obtained for diethylstilbestrol, safrole, acetamide, urethane and ethionine at the concentrations used. Caprolactam did not show any mutagenic effect on C658-K42 at concentrations up to 20 mg/ml. Sodium azide, which is unlikely to be carcinogenic but is strongly mutagenic in the Ames test, showed a very weak mutagenic effect on C658-K42. 相似文献
109.
110.
Based on a standard constant-pressure Monte Carlo molecular simulation, we have studied liquid crystal phases of binary mixtures of nonspherical molecules. The components of the mixtures are two types of hard Gaussian overlap (HGO) molecules. The first type of molecule has a small molecularelongation parameter (short HGO molecules) and cannot form stable liquid crystal phase in the bulk by themselves. The second type of molecule has a large elongation parameter (long HGO molecules) and can form a liquid crystal phase easily. In the mixtures, the short HGO molecules can form an orientationally ordered phase because the long HGO molecules form confining surfaces to induce the alignment of the short molecules. We also study the isotropic-nematic phase transition in different mixtures composed of short and long HGO molecules with different elongations and concentrations. The obtained result implies that small anisotropic molecules can show liquid crystal behavior. 相似文献