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81.
Yoshio Oyumi Kiyotaka Inokami Kazuhiro Yamazaki Koki Matsumoto 《Propellants, Explosives, Pyrotechnics》1994,19(4):180-186
Thermal decomposition and the burning properties of BAMO based propellants with HMX or AN/HMX have been investigated. The heat generated by the azide binder decomposition initiated and accelerated the thermal decomposition of HMX and AN. Ammonium perchlorate (AP) and lead stearate with carbon black significantly altered the mechanisms of the thermal decomposition and the burning properties of the HMX based propellants. AP showed an increase in burning rate with a slight decrease in burning rate pressure exponent. The lead catalyst yielded high value of the burning rate with the lowest pressure exponent. The ammonium dichromate also influenced the mechanisms of the thermal decomposition and the burning properties of the AN/HMX samples. The combination of ammonium dichromate and copper chromite was the most effective on the burning rate augmentation of AN/HMX based propellants. AN sublimed and evaporated from the condensed phase and mainly reacted exothermically in the gas phase HMX and AN/HMX based propellants showed smokeless burning characteristics in the small rocket motor combustion tests. 相似文献
82.
Koji Ishiguro Yoto SameshimaTakashi Kume Ken-ichiro IkedaJun Matsumoto Makoto Yoshimoto 《Food chemistry》2012,131(3):774-779
We have investigated angiotensin I-converting enzyme (ACE) inhibitory activity in an enzyme digest of sweetpotato protein, the antihypertensive effect of the digest in spontaneously hypertensive rats (SHR), and the identification of an ACE inhibitory peptide. Protein was prepared from squeezed juice of sweetpotato by isoelectric focusing precipitation. Three kinds of proteases were selected for effective protein digestion. The digest, sweetpotato peptide (SPP), exhibited strong ACE inhibitory activity (IC50: 18.2 μg/ml). SPP was orally administered by gavage to SHR at a dose of 100 mg/kg or 500 mg/kg. The systolic blood pressure and the diastolic blood pressure were measured at 0 (before administration), 2, 4, 8, and 24 h after administration. A dose-dependent decrease in systolic blood pressure in SHR was observed after oral administration of SPP. Significant differences between SPP-administered rats and control rats were observed 4 and 8 h after administration in the 500 mg/kg-administered group and 8 h after administration in the 100 mg/kg-administered group. Diastolic blood pressure also decreased in the SPP-administered groups, although the difference between SPP-administered rats and control rats was not significant. These results suggest that SPP may be useful in the prevention or treatment of hypertension. Peptides with ACE inhibitory activity were purified from SPP by absorption chromatography and preparative HPLC using an ODS column. The amino acid sequences of isolated peptides were I-T-P, I-I-P, G-Q-Y and S-T-Y-Q-T; their ACE inhibitory activities (IC50) were 9.5 μM, 80.8 μM, 52.3 μM and 300.4 μM, respectively. In conclusion, I-T-P is a novel, strong ACE inhibitory peptide. 相似文献
83.
Sterol composition of 19 vegetable oils 总被引:6,自引:4,他引:6
The unsaponifiables from 19 vegetable oils were divided into a sterol and three other fractions by thin-layer chromatography.
All except olive and palm kernel oils gave the sterol fraction in a large quantity. Compositions of the sterol fractions were
determined by gas liquid chromatography. Identification of each sterol was carried out by gas liquid chromatography and combined
gas chromatograph-mass spectrometry. Campesterol, stigmasterol and β-sitosterol were present in all oils, and a minor amount
of cholesterol in majority of the oils. Brassicasterol occurrence was widespread but its content was extremely small in oils
other than rapeseed oil. Other sterols, presumably δ7-stigmastenol and δ5- and δ7-avenasterol were detected in most of the oils. 相似文献
84.
Sterols,methylsterols, and triterpene alcohols in threeTheaceae and some other vegetable oils 总被引:4,自引:0,他引:4
The unsaponifiables from threeTheaceae (Camellia japonica L.,Camellia Sasanqua Thunb., andThea sinensis L.) oils and alfalfa, garden balsam, and spinach seed oils and shea fat were separated into four fractions: sterols, 4-methylsterols,
triterpene alcohols, and less polar compounds by thin layer chromatography. While the sterol fraction was the major one for
the unsaponifiables from alfalfa and spinach seed oils, the triterpene alcohol fraction was predominant for the unsaponifiables
from all other oils. The sterol, 4-methylsterol, and triterpene alcohol fractions were analyzed by gas chromatography. All
the sterol fractions were alike in their compositions, consisting exclusively of Δ7-sterols, such as α-spinasterol and Δ7-stigmastenol as predominant components together with Δ7-avenasterol and 24-methylcholest-7-enol. Obtusifoliol, gramisterol (occasionally accompanied with cycloeucalenol), and citrostadienol,
together with several other unidentified components, were found in the 4-methylsterol fractions from all of the oils except
shea fat. The 4-methylsterol fraction from shea fat showed a characteristic composition containing a large proportion of unidentified
components which had relative retention time greater than that of citrostadienol, while no citrostadienol was detected. β-Amyrin,
lupeol, and butyospermol were major components of the triterpene alcohol fractions from most of the oils, but the fraction
from spinach seed oil contained cycloartenol and 24-methylene-cycloartanol as predominant components. There is a close similarity
in the compositions of unsaponifiables (sterols, 4-methylsterols, and triterpene alcohols) of the threeTheaceae oils. Two sterols, α-spinasterol and Δ7-stigmastenol, and five triterpene alcohols were isolated from tea seed oil. Moreover, five unidentified components beside
parkeol, butyrospermol, α-amyrin, and lupeol were isolated from the triterpene alcohol fraction of shea fat. 相似文献
85.
Visible-light-active titanium oxide photocatalyst realized by an oxygen-deficient structure and by nitrogen doping 总被引:41,自引:0,他引:41
T. Ihara M. Miyoshi Y. Iriyama O. Matsumoto S. Sugihara 《Applied catalysis. B, Environmental》2003,42(4):403-409
A visible-light (vis)-active titanium oxide photocatalyst was prepared by a simple wet process: the calcination of the hydrolysis product of Ti(SO4)2 with ammonia using an ordinary electric furnace in dry air at 400 °C. The color of this photocatalyst was vivid yellow and absorbed light in the blue (400 nm) to bluish-green (550 nm) region exclusively. Its structure was characterized to anatase with oxygen-deficient stoichiometry by XRD and X-ray photoelectron spectroscopy. Nitrogen was also detected, but only in trace amounts. Using blue-light-emitting diodes as a light source, 540 ppm of acetone was decomposed within 36 h and a stoichiometric yield of CO2 was obtained. From the results of the crystalline size D, it was found that vis-activity could be realized on polycrystalline particles and the grain-boundaries (GBs) are thought to be important, since oxygen vacancies are easily created in GBs, which could form a GB state. Finally, we concluded that oxygen-deficient sites formed in GBs are important to emerge vis-activity, and nitrogen doped in the part of oxygen-deficient sites are important as a blocker for reoxidation. 相似文献
86.
The soft texture of the pizza crust rim is generated by baking at a high temperature for a short period in a stone oven. In the case of baking in an electric oven, the pizza dough is baked at a much lower temperature and for a longer period, resulting in a harder texture. To improve the texture of electric oven-baked pizza crust, the effects of water and gelatinized starch on the viscoelasticity of pizza dough and the texture of pizza crust were investigated. Rheological properties (storage modulus, loss modulus, and yield stress) of pizza dough decreased with an increase in water content. When wheat flour in the dough was partially replaced with pre-gelatinized wheat starch, the rheological properties of the dough were maintained even at a high-water content. These results indicate that water-enriched dough can be prepared with gelatinized starch and baked using an electric oven. There was no significant difference in apparent density between the conventional and modified pizza crusts. Water content of the crumb part of the modified crust was significantly higher than that of the conventional crust. Texture analysis revealed that the modified pizza crust showed significantly lower stress at high strain than the conventional crust. In addition, sensory evaluation showed that the modified pizza crust exhibited greater firmness and stickiness than the conventional crust, which was attributed to the increased water content with gelatinized starch of the dough. 相似文献
87.
We attempted to produce a Ti45Zr38Ni17 bulk icosahedral (i) quasicrystal by a shock compression technique, in which a single-stage powder gun discharges a flyer plate that consolidates the target powders. The results were also compared with those by a conventional hot-pressing. The powder mixtures for the shock compression were blended by two kinds of methods; that is, gently mixing in a vial, and mechanically alloying by a planetary ball mill. A large bulk i-phase sample, with a Ti2Ni crystal phase, was synthesized from mechanically alloyed powders after shock compression at a higher flyer velocity, although the conventional hot-pressing at 3 MPa synthesized only the Ti2Ni phase. For the gently mixed powders, no reaction occured even after shock compression. High-pressure and high-temperature produced during shock compression, and milling process were key factors to obtain the i-phase. The Vickers hardness and the wetting contact angle with pure water under an atmospheric pressure for the bulk sample containing the i-phase were about 7 GPa and about 70°, respectively. 相似文献
88.
All-optical 2R regeneration of two-wavelength time-interleaved signals is demonstrated using higher order four-wave mixing in a fiber. In this regeneration scheme, a single fiber and a pump are shared by the two channels. The results show that interchannel crosstalk can be avoided when pulses in the two channels are time separated by more than ~3 times their pulsewidth. A possible power monitoring to determine suitable time-interleaving condition is also discussed. 相似文献
89.
Toshiro Matsui Xiao-Lin Zhu Koso Shiraishi Tatsuro Ueki Yoshiharu Noda Kiyoshi Matsumoto 《Journal of food science》2010,75(4):H129-H134
ABSTRACT: In this study, we focused on the antihypertensive effect of newly fermented salt-free soy sauce (SFS) in spontaneously hypertensive rats (SHRs). A 13-wk oral administration of SFS was performed daily in 8- to 21-wk-old SHRs with a dose of 200 mg/kg of body weight/d. The systolic (SBP) and diastolic (DBP) blood pressures were measured for each week during the experimental period. As a result, a significant (P < 0.01) BP lowering effect was observed from the 5th d to the end of the experiment in the SFS group compared with the control group (ΔSBP21-wk: 27 mmHg, ΔDBP21-wk: 20 mmHg). In contrast to such substantial effect by SFS intake, angiotensin I-converting enzyme activities in blood and local organs as well as pharmaceutical parameters such as serum Na+ or K+ level did not show any significant difference between in both SFS and control groups. Vasoconstriction experiment using thoracic aorta rings from 21-wk SHRs provided an interesting result that the rings from the SFS group evoked a >2-fold higher increase in the angiotensin II-stimulated constrictive response compared with the rings from the control group (P = 0.012), which suggested that the SFS-intake would be effective in possessing a higher vessel tone. Practical Application: In this study, we investigated the antihypertensive effect of newly fermented SFS in SHRs. As a result of 13-wk SFS-administration, we found a significant antihypertensive effect of the SFS. This finding strongly demonstrates that the developed SFS would be greatly beneficial for health and useful for health-related industries. 相似文献
90.
Shiv Shankhar Kaundun Satoru Matsumoto 《Journal of the science of food and agriculture》2011,91(14):2660-2663
BACKGROUND: Tea is the most consumed beverage worldwide after water. Yet very little is known about the genetics of tea in comparison with other crop species. Here we have taken advantage of the polymorphic nature of microsatellite DNA to investigate the mode of chloroplast inheritance in tea, Camellia sinensis (L.) O. Kuntze. This is important for the correct interpretation of phylogeny and introgression data as well as assessing the suitability of chloroplast transformation as a means for transgene containment in tea. RESULTS: The study was based on six Japanese tea cultivars, namely Aj2, CK23, Hatsumomiji, Nka05, Yamanoibuki and Kanayamidori used to generate four informative families. The parental pairs in the crosses differed at a single chlroroplast locus with respect to an imperfect microsatellite repeat of 16 nucleotide bases. In agreement with earlier cytological studies, all 61 progeny displayed a cpDNA profile that was consistent with the maternal inheritance of chloroplasts in tea. CONCLUSIONS: The data generated here provide the first molecular evidence of the plastid inheritance in tea. However, we suggest that additional families and polymorphic markers be screened for increasing the confidence in the observed maternal inheritance of chloroplasts in this important crop species. Copyright © 2011 Society of Chemical Industry 相似文献