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排序方式: 共有849条查询结果,搜索用时 859 毫秒
11.
S Mori T Konishi K Matsuoka M Deguchi M Ohta O Mizuno T Ueno T Okinaka Y Nishimura N Ito T Nakano 《Canadian Metallurgical Quarterly》1998,37(7):606-610
We report a nephrotic syndrome patient with eosinophilia who developed ileus, epigastralgia and malabsorption due to strongyloidiasis which became symptomatic by steroid therapy. The patient was then treated with thiabendazole and recovered. A percutaneous renal biopsy revealed minimal change nephrotic syndrome. This renal injury may be brought on by severe infection of Strongyloides stercoralis. It is important to rule out strongyloidiasis prior to corticosteroid therapy to patients from eosinophilia endemic areas. 相似文献
12.
13.
Minoru Ueno Satoshi Yamamoto Kenjiro Meguro 《Journal of the American Oil Chemists' Society》1974,51(8):373-376
Several salts of α,ω-sulfates, MO3SO(CH2)n OSO3M(n=12, 14, 16, 18, and M=Li, Na, and K) were prepared from the corresponding α,ω-alkane diols. The Krafft points of these
α,ω-sulfates with common counterion as estimated by electroconductivity measurements increased with the increase of the hydrocarbon
chain length, and the effect of the counterions on the Krafft points of the α,ω-sulfates with the same hydrocarbon chain length
was in the order : Li<Na<K. Solutions of the α,ω-sulfates, except disodium dodecanediol disulfate, showed two break points
corresponding to the first and second critical micelle concentration in each plot of the electroconductivity as a function
of the concentration. The existence of the second break point suggested that another aggregation of rearrangement of the existing
aggregates occurs in α,ω-sulfate solutions in addition to the usual micelle formation. The first and second break points of
α,ω-sulfates with sodium counterion decreased logarithmically with increasing total number of methylene groups. The relationships
were given as follows: log(first break point)=−0.138Nc−0.095; log(second break point)=−0.104Nc−0.251. The effect of the counterions
upon the break points of α,ω-sulfates with the same hydrocarbon chain length was in accordance with their positions in the
lyotropic series. 相似文献
14.
M. Takeuchi S. Ueno E. Flöter K. Sato 《Journal of the American Oil Chemists' Society》2002,79(7):627-632
The binary phase behavior of SOS (1,3-distearoyl-2-oleoyl-sn-glycerol) and SLS (1,3-distearoyl-2-linoleoyl-sn-glycerol) was examined by using DSC and conventional and synchrotron radiation X-ray diffraction. The solid-solution phases
were observed in the metastable α and γ forms in all concentration ranges. Results indicated that the miscible γ form did
not transform to the β′ form when the mixtures were subjected to simple cooling from a high-temperature liquid to a low-temperature
solid phase. However, and α-melt-mediated transformation into β′ and β2 resulted in the formation of immiscible phases in concentration ranges of SLS below 30%. By contrast, at SLS concentration
ranges above 30%, the α-melt-mediated transformation caused crystallization of only the γ form, and β′ and β2 crystals did not appear. These results show that the specific interactions between SOS and SLS are operative in the phase
behavior of the mixture states of SOS and SLS. 相似文献
15.
T.?Sonoda Y.?Takata S.?Ueno K.?SatoEmail author 《Journal of the American Oil Chemists' Society》2004,81(4):365-373
The crystallization and polymorphic behavior of palm stearin (PS) in a bulk state and in oil-in-water (O/W) emulsion droplets
(average diameter, 1.7±0.3 μm) was observed by using DSC, optical microscopy, and in situ X-ray diffraction with synchrotron radiation (SR-XRD). For the bulk sample the DSC measurements revealed three main exothermic
peaks at approximately 31 (large), 21 (small) and 3°C (medium) on cooling, and broad endothermic peaks at approximate −3 (small),
8, 15 to 25 (medium), and 37 and 53°C upon heating. The SR-XRD patterns taken during cooling from 60 to −5°C clarified that
the DSC exothermic peaks around 31 and 3°C corresponded to crystallization of the α form of high-melting and low-melting fractions,
respectively, and that the occurrence of β′ corresponded to the small exothermic peak around 21°C. The XR-XRD patterns taken
during heating from −5 to 60°C demonstrated that the DSC endothermic peaks corresponded to the following transformation processes:
melting of α of the low-melting fraction (−3°C), melt-mediated transformation from α to ∇′ (15–25°C), melting of β′ (36°C),
and melting of β (53°C) of the high-melting fraction. As for the O/W emulsion sample, the DSC and SR-XRD measurements during
the cooling and heating processes exhibited basically the same behavior as that of PS in the bulk state, except that β′ did
not crystallize during the cooling process, and the temperatures of crystallization of α, melt-mediated α→β′→β transformation,
and melting of β were lower in the emulsion droplets than in the bulk state. 相似文献
16.
Ru-doped nanostructured carbon films 总被引:1,自引:0,他引:1
Pure and Ru-doped carbon films are deposited on Si (100) substrates by electron cyclotron resonance chemical vapor deposition. The films are characterized by transmission electron microscopy, electron energy loss spectroscopy, energy dispersive X-ray spectroscopy and atomic force microscopy. In both the pure and Ru-doped samples, diamond nanocrystallites are formed in amorphous carbon matrices. The Ru-doped film contains much smaller diamond nanocrystallites (approx. 3 nm) than the pure samples (approx. 11 nm). Lower surface roughnesses are observed in both pure and Ru-doped samples as compared to other reported nanocrystalline diamond films. The conductivity of the Ru-doped film is significantly higher than that of the pure film. The results show that Ru-doped nanocrystalline diamond films have unique structures and properties as compared to pure nanocrystalline diamond films or metal doped diamond-like carbon films, which may offer advantages for electrochemical, optical-window, field emission or tribological applications. 相似文献
17.
M. Toriumi N. Hayashi M. Hashimoto S. Nonogaki T. Ueno T. Iwayanagi 《Polymer Engineering and Science》1989,29(13):868-873
The design and preparation of a series of negative resists for KrF excimer laser lithography are described. Each resist is composed of poly(hydroxystyrene) and an aromatic azide. The base resin shows high transmittance of 62%/μm at 248 nm, when p-ethylphenyl p-azidophenylsulfonate. 4-azido-4α-methoxy-chalcone, 1-(4 azidobenzylidene)-3-(α-hydroxy-4-azidobenzyl)-indene, 4,4α-diazido-3,3α-dimethoxybiphenyl, or 1-(4-azidostyryl)-5, 5-dimethyl-2-cyclohexen-1-one is employed as a sensitizer. These azides are obtained by red-shifting the absorption maxima to lower energy regions than the exposing wavelength of 248 nm. Transmittance of resists can be controlled from 10 to 30%. The resist is exposed with a KrF excimer laser stepper and developed in an alkaline solution. Sensitivities of about 15 mJ/cm2 are observed. A good, subhalf-micron resist profile is achieved. The photochemical reaction mechanisms of poly(hydroxystyrene) and 4,4α-diazido-3,3α-dimethoxybiphenyl were studied at 248 nm and 313 nm exposure. Quantum yield for photodecomposition at 248 nm is seven times larger than that at 313 nm, but dissolution-inhibition effects are larger at 313 nm exposure. Consequently, the resist shows higher sensitivity at 313 nm than at 248 nm. 相似文献
18.
The micellar properties of aqueous binary mixed solutions for two systems consisting of sodium cholate (NaC)-octaoxyethylene
glycol mono n-decyl ether (C10E8) and sodium glycocholate (NaGC)-C10E8 have been studied on the basis of surface tensions, polarity of the micelle interior and the mean aggregation number. Application
of two theoretical treatments, based on regular solution and excess thermodynamic quantities for critical micellar concentration
(CMC) data from surface tension curves of two mixed systems showed that the mole fraction of each bile salt in the mixed micelles
near the CMC is lower than that of the corresponding prepared mole fraction in the mixed solution. The polarity of the interior
suggested that the hydrophobicity of intramicelles increased with the increase of the mole fraction of bile salt in the mixed
solution and that the mixed micelles become dramatically more hydrophobic at a mole fraction of 0.68 for NaGC−C10E8 system and 0.75 for NaC−C10E8 system, respectively. This implies that the micelles become richer in the bile salt molecules and the tendency appears strongly
for NaGC−C10E8 system due to the strong cohesion between the conjugated glycines in the NaGC molecules. The decrease of aggregation number
with the increase of the mole fraction of bile salts shows that the micelles approach those of the single system of each bile
salt. This supports the previously mentioned facts. 相似文献
19.
α-Tocopherol was reacted with methyl linoleateperoxyl radicals at 37°C. The peroxyl radicals were generated by the reaction
of methyl linoleate with a free radical initiator, 2,2′-azobis(2,4-dimethylvaleronitrile). The primary products of α-tocopherol with methyl linoleate-peroxyl radicals were isolated by
reversephase and normal-phase high performance liquid chromatography (HPLC), and their structures were characterized by ultraviolet
(UV), infrared (IR),1H and13C nuclear magnetic resonance (NMR) and mass spectrometry (MS). There were four stereoisomers of methyl 13-(8a-peroxy-α-tocopherone)-9(Z),11(E)-octadecadienoate and four stereoisomers of methyl9-(8a-peroxy-α-tocopherone)-10(E),12(Z)-octadecadienoate. 相似文献
20.
Shin-ichiro Sekimiya Eikoh Kobayashi Nobukatsu Nemoto Yukihiko Ueno Koji Ikeda Nobuo Takamiya 《Polymer Bulletin》1991,27(1):37-40
Summary Liquid crystalline side-chain polysiloxanes were prepared without metal complex catalyst. Mesogenic groups such as cholesteryl, 4-cyano-4-biphenyl and 4-methoxy-4-biphenyl group were introduced into polysiloxane by esterification and from DSC measurements they were compatible with other liquid crystalline polysiloxanes reported previously. 相似文献