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61.
62.
Gold was deposited on top of hydrogen saturated Si(1 1 1) clean surfaces. The electronic nature and atomic intermixing between gold overlayer and silicon substrate were studied by AES and ELS. It is claimed that there is a critical thickness (~ 2 ML), where 1 ML = 7.8 × 1014 atoms cm?2 for Si(1 1 1), for gold to induce alloyed metallic overlayer formation on the surface of a specimen due to intermixing reaction independently whether a surface of Si(1 1 1) substrate is saturated with hydrogen atoms or not. 相似文献
63.
In the previous paper, we reported that 67Ga was accumulated in abscess and uptake rate of 67Ga in abscess increased with time after the injection of 67Ga-citrate. The present study was undertaken to elucidate the influence of blood flow on the accumulation of 67Ga in abscess. Five days after subcutaneous injection of 0.2 ml of turpentine to the rats, 131I-human serum albumin (HSA) was injected intravenously to the rats. At an appropriate time after the injection (10 min to 6 days), uptake rates of 131I-HSA in abscess and normal tissues were measured. Similarly, 51Cr-red blood cells (RBC) were injected intravenously to the above rats and the uptake rates of 51Cr-RBC were also measured. One, three, and 24 hours after injection of 131I-HSA, the uptake rates of 131I-HSA in abscess were 1.32 %dose/g, 1.84 %dose/g, and 0.82 %dose/g, respectively. However, the uptake rates of 51Cr-RBC in abscess was very small, and the value was 0.14 %dose/g at 24 hours after the injection. In the case of abscess, blood in the tissue fluid was very little, but the permeability of 131I-HSA from the blood vessel in the tissue was much larger than that of normal tissues. From these facts, it was deduced that the accelerated permeability caused the abscess accumulation of 67Ga. 相似文献
64.
65.
Both (3S,4R)-(+)- and (3R,4S)-(?)-enantiomers of faranal [(6E,10Z)-3,4,7,11-tetramethyl-6,10-tride- cadienal] were synthesized. The former was comparable in bioactivity with that of the natural trail pheromone isolated from Monomorium pharaonis. 相似文献
66.
Masayoshi Onishi Katsuma Hiraki Koichi Maeda Toshihiro Itoh 《Journal of organometallic chemistry》1980,188(2):245-253
The 2-picolylpalladium(II) complex [{Pd(CH2Py)Cl(PPh3)}2] (CH2Py=2-picolyl) (I), prepared from 2-picolyl chloride and [Pd(PPh3)4], was treated with lithium bromide, silver acetate, 4-picoline (pic) and silver perchlorate, thallium acetylacetonate{Tl(acac)}, sodium dimenthyldithiocarbamate-water-(1/2) {Na(dmdc). 2 H2O}, and 1,2-bis(diphenylphospino)ethane (dppe) to yield [{PdBr(CH2Py)(PPh3)}2] (II), [{Pd(CH2Py)OAc(PPh3)}2] (III), [{Pd(Ch2Py)(pic)(PPh3)}2](ClO4)2 (IV), [Pd(CH2Py)(acac)(PPh3)] (V), [Pd(CH2Py)(dmdc)(PPh3)] (VI), and [Pd(Ch2Py)Cl(dppe)] (VII), respectively. Halogen abstraction from VII using silver perchlorate afforded an ionic complex [{Pd(CH2Py)(dppe)}2](ClO4)2 (VIII). It was concluded that the 2-picolyl groups in these eight complexes are σ-bonded to palladium, and that in the dinuclear complexes I, II, III, IV, and VIII, they serve as bridging ligands. 相似文献
67.
Hidefumi Hirai Katsuma Hiraki Isamu Noguchi Shoji Makishima 《Journal of polymer science. Part A, Polymer chemistry》1970,8(1):147-156
ESR spectra of homogeneous catalyst systems derived from n-butyl titanate and triethylaluminum at Al/Ti molar ratios of 1.0–10 were observed in toluene solution at several temperatures from ?78°C to +25°C. In the whole range of Al/Ti molar ratios, a single signal with a g value of 1.951 was observed at ?78°C and was associated with the first reaction intermediate. With increasing temperature, the intensity of the signal decreased gradually, while two series of signals appeared, depending on the Al/Ti molar ratio. At an Al/Ti molar ratio of 1.7, seven kinds of signals with g values of 1.960, 1.946, 1.950, 1.959, 1.980, 1.977, and 1.978, respectively, were observed. On the other hand, four kinds of signals with g values of 1.934, 1.966, 1.952, and 1.979, respectively, were found at Al/Ti molar ratios larger than 3. The structures of the species corresponding to the signals were discussed on the basis of the ESR spectra, the order of their growth and their hyperfine structures being considered. Two series of ESR signal were correlated to two kinds of active species for polymerization of styrene and butadiene, respectively. 相似文献
68.
Masayoshi Onishi Katsuma Hiraki Atsushi Iwamoto 《Journal of organometallic chemistry》1984,262(2):c11-c13
A 1,2-disubstituted ferrocene derivative, 2-[(dimethylamino)methyl]-1-hydroxyferrocene (I), was prepared from 2-[(dimethylamino)methyl]-1-iodoferrocene via 2-[(dimethylamino)methyl]-1-acetoxyferrocene. On complexation, compound I served as a stable monovalent chelate ligand of a 1,2-disubstituted ferrocene derivative. In addition, a dihydroxy derivative, 2-(hydroxymethyl)-1-hydroxyferrocene, was obtained from hydrolysis of the methiodide formed from I. 相似文献
69.
A new method has been developed for imaging the thyroid gland by the use of 201Tl radioactive implant induced X-ray emission (RIXE). The thyroid phantom was made from two cylindrical tubes embedded in plastic neck phantom. Each tube consisted of stable iodine and 201Tl radioactive source in 10 ml water solution. Some photopeaks in the energy range from 20 to 200 ke V were scanned along a horizontal axis by the collimated Ge detector with high energy resolution. The distribution on the horizontal axis was obtained for the generated I K alpha-ray and some primary 201Tl radiations. The 201Tl RIXE scanning can provide information about the distribution of iodine with 201Tl as well as 201Tl distribution in the thyroid gland. The effectiveness of the 201Tl RIXE technique as a thyroid scanning method is discussed. 相似文献
70.
Masayoshi Onishi Katsuma Hiraki Yushichiro Ohama Atsushi Kurosaki 《Journal of organometallic chemistry》1985,284(3):403-408
Thallium [1-(p-tolylimino)-2-methylpropyl]cyclopentadienide, Tl[C5H4C(=NC6H4CH3)CH(CH3)2], was prepared and treatment of the salt with [{PdCl2(PREt2)}2] (R = Ph and Et) yielded mononuclear palladium(II) complexes, [Pd{η5-C5H4C(=NC6H4CH3)CH(CH3)2}Cl(PREt2)], with an imidoyl-substituted η5-cyclopentadienyl group. In addition, [Pd(η5-C5H4-COY)Cl(PPhEt2)] (Y = CH3 and OCH3) complexes were obtained from the sodium salts of their substituted cyclopentadienyl groups. These new compounds were characterized by means of 1H and 13C NMR and IR spectroscopy. 相似文献