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121.
H Mugishima M Iwata I Okabe E Sanuki N Onuma T Fujimoto M Ohira M Kaneko Y Tsuchida M Okuni 《Canadian Metallurgical Quarterly》1994,74(3):972-977
BACKGROUND: Encouraging results have been reported with high dose chemotherapy and total body radiation followed by bone marrow autotransplantation in children with advanced neuroblastoma; however, relapse remains a significant problem. METHODS: The authors treated 22 children with advanced neuroblastoma with high dose chemotherapy, surgery, intraoperative radiation, and a bone marrow autotransplant (treated in vitro to remove tumor cells) followed by 13-cis-retinoic acid. RESULTS: The 3-year relapse rate was 25% (95% confidence interval [CI], 6-44%). The 3-year disease free survival rate was 72% (95% CI, 52-92%). Toxicities included hemolytic uremic syndrome, herpes infection, and hepatic venoocclusive disease. CONCLUSION: These data suggest that this treatment strategy offers an increased rate of 3-year disease free survival. The nonrandomized nature of this study and its use of multiple modalities precludes the analysis of the specific contribution of each treatment component and comparison with conventional therapy. 相似文献
122.
Washio K. Okabe T. Norisue K. Nagashima T. 《Solid-State Circuits, IEEE Journal of》1992,27(9):1264-1269
An all-band TV tuner IC with an on-chip PLL and a high-voltage output stage is developed. The use of a self-aligned bipolar technology called high-voltage compatible sidewall base contact structure (HV-SICOS) allows the integration of 1-GHz analog circuits, 1-GHz low-power ECL-I2L PLL circuits, and a 0.5- to 30-V tuning diode bias current on the same chip. The analog block has a VCO and mixer pair for the VHF/CATV and another pair for the UHF bands, a UHF input amplifier, an IF amplifier, and a VCO signal switching circuit. To suppress the digital noise level for mixed analog/digital mode operation, the PLL is constructed with high-speed ECL circuits for divide-by-four and dual modulus prescalers, and low-power I2L circuits. An isolation area is placed between the analog and digital blocks. Conversion gain of 24 dB for VHF/CATV and 33 dB for UHF, a noise figure of 10 dB, and 1% cross modulation of 95 dB-μV are obtained. This IC operates with a total power dissipation of 200 mW on a 3-mm×4-mm chip 相似文献
123.
K Kawagoe D Kitamura M Okabe I Taniuchi M Ikawa T Watanabe T Kinoshita J Takeda 《Canadian Metallurgical Quarterly》1996,87(9):3600-3606
Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hematopoietic stem cell disorder characterized by complement-mediated hemolysis. Abnormal hematopoietic cells from patients with PNH are deficient in glycosylphosphatidylinositol (GPI)-anchored proteins and clonally dominate various hematopoietic lineages in the bone marrow and the peripheral blood. Analysis of many patients with PNH has showed that somatic mutation in the X-linked gene PIG-A is responsible for the GPI-anchor deficiency in PNH. The PIG-A mutation must also be relevant to the clonal dominance of GPI-anchor deficient (GPI-) blood cells because two or more PIG-A mutant clones become dominant in many patients. However, whether the PIG-A mutation alone is sufficient for clonal dominance is not known. To address this question, we generated chimeric mice using Pig-a (the murine homologue of PIG-A) disrupted embryonic stem (ES) cells, in which the animals are chimeric with respect to the surface expression of GPI-anchored proteins. The chimerism of hematopoietic and nonhematopoietic tissues in such mice was always low, suggesting that the higher contribution of Pig-a disrupted GPI- cells had a lethal effect on the chimera. GPI- cells appeared in the peripheral blood of some of the chimeric mice. However, the percentage of GPI- erythrocytes did not increase for 10 months after birth, implying that the Pig-a mutation alone does not immediately cause the clonal dominance of GPI- blood cells; another pathologic or physiologic change(s) in the hematopoietic environments or in the clone itself may be necessary. 相似文献
124.
Y Wada N Wada M Kubo M Nagata O Tatsuzawa M Okazaki T Oishi K Joh T Okabe S Kohno 《Canadian Metallurgical Quarterly》1998,38(3):496-503
We compared clinical findings in 12 cases of systemic lupus erythematosus (SLE) in boys with those in 49 cases in girls. The age at which SLE developed in boys was consistent with that of infantile SLE and there was no age specificity. Momy cases in boys were diagnosed earlier as compared with cases in girls. Symptoms of infantile SLE, such as fever, arthalgia, butterfly rash, and urinary abnormalities, did not differ between boys and girls. However, a higher percentage of boys (58.3%) had central nervous system complications at onset than did girls (30.6%). Platelet counts tended to be higher in boys than in girls, a finding that suggests SLE tends to be more severe in boys than in girls. The incidence in the appiarance of LE cells, anti-Sm antibodies and immune complexes was higher in boys than in girls. Type IV or V renal pathologic changes (World Health Organization Histologic Classification) were present in 70% of boys. Our findings suggest that SLE in boys is more severe than that in girls and is more likely to be associated with central nervous system complications and severe renal complications. 相似文献
125.
M Murakoshi H Nishino Y Satomi J Takayasu T Hasegawa H Tokuda A Iwashima J Okuzumi H Okabe H Kitano 《Canadian Metallurgical Quarterly》1992,52(23):6583-6587
Although beta-carotene has been considered to be a key cancer preventive agent in green and yellow vegetables, other types of carotenoids, such as alpha-carotene, may also contribute to anticarcinogenic action, since these carotenoids usually coexist with beta-carotene and are detectable in human blood and tissues. In this study, we compared the inhibitory effect of natural alpha-carotene, obtained from palm oil, with that of beta-carotene on spontaneous liver carcinogenesis in C3H/He male mice. The mean number of hepatomas per mouse was significantly decreased by alpha-carotene supplementation (per os administration in drinking water at a concentration of 0.05%, ad libitum) as compared with that in the control group (P < 0.001, Student's t test). On the other hand, beta-carotene, at the same dose as alpha-carotene, did not show any such significant difference from the control group. Furthermore, we also compared the antitumor-promoting activity of alpha-carotene with that of beta-carotene against two-stage mouse lung carcinogenesis (initiator, 4-nitroquinoline 1-oxide; promoter, glycerol). alpha-Carotene, but not beta-carotene, reduced the number of lung tumors per mouse to about 30% of that in the control group (P < 0.001, Student's t test). The higher potency of the antitumor-promoting action of alpha-carotene compared to beta-carotene was confirmed in other experimental systems; e.g., alpha-carotene was also found to have a stronger effect than beta-carotene in suppressing the promoting activity of 12-O-tetradecanoylphorbol-13-acetate on skin carcinogenesis in 7,12-dimethylbenz[a]anthracene-initiated mice. These results suggest that not only beta-carotene, but also other types of carotenoids, such as alpha-carotene, may play an important role in cancer prevention. 相似文献
126.
Pectin‐[(3‐acrylamidopropyl) trimethylammonium chloride‐co‐acrylic acid] hydrogel prepared by gamma radiation and selectively silver (Ag) metal adsorption
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Pectin‐[(3‐acrylamidopropyl) trimethylammonium chloride‐co‐acrylic acid] hydrogel has been prepared from the aqueous blend solution of pectin, (3‐acrylamidopropyl) trimethylammonium chloride (APTAC), and acrylic acid (AAc) by applying gamma radiation of different doses (1–25 kGy) from 60Co gamma source. The hydrogels were characterized by equilibrium swelling, Fourier transform infrared, differential scanning calorimetry, and scanning electron microscopy. The hydrogels were used in multielement adsorption and it was found that pectin‐(APTAC‐co‐AAc) gel is highly selective toward silver (I) ion among 27 metal ions. The data obtained from equilibrium adsorption studies were fitted in Langmuir and Freundlich adsorption isotherm models and model parameters evaluated. The maximum adsorption capacity of pectin‐(APTAC‐co‐AAc) gel was found to be 67.6413 mg/g of dry gel at sample volume of 25 mL. The kinetic data were tested using pseudo‐first order and pseudo‐second order kinetic models and different adsorption diffusion models such as film diffusion and intra‐particle diffusivity model. Thiourea solution was used for desorption of adsorbed metal ions from the hydrogel. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45906. 相似文献
127.
The purpose of this investigation was to analyze the fundamental wear properties of new porous carbon materials Woodceramics. Wear tests were carried out by sliding an alumina ball (R=1.5, 4.0 mm) or hemispherical diamond pin (R=0.075 mm) against a Woodceramics plate (MDF-800), under three lubrication conditions: unlubricated in air, impregnated with base oil, and in water. The specific wear rate was calculated from the profile of the worn surfaces, and the relationship between the specific wear rate and the contact pressure parameter (W/R
2)1/3 was obtained. Worn surfaces were observed with a scanning electron microscope (SEM) to clarify the microscopic wear mechanisms. The following principal results were obtained: (1) The specific wear rate of Woodceramics increases rapidly with increasing contact pressure parameter (W/R
2)1/3, under all lubricated conditions; (2) When the contact pressure parameter (W/R
2)1/3 is less than a certain critical value, the specific wear rate of Woodceramics is less than 10–8 [mm2/N], which is low enough for practical use; (3) The wear mode of Woodceramics can be classified into the following three modes: large-scale brittle fracture-induced wear (flake formation), small-scale brittle fracture-induced wear (powder formation), and ultra mild wear (ploughing). 相似文献
128.
Yosio Edemir Shimabukuro Egidio Arai Valdete Duarte Anderson Jorge Erone Ghizoni dos Santos Kaio Allan Cruz Gasparini 《International journal of remote sensing》2019,40(14):5475-5496
Deforestation is the replacement of forest by other land use while degradation is a reduction of long-term canopy cover and/or forest stock. Forest degradation in the Brazilian Amazon is mainly due to selective logging of intact/un-managed forests and to uncontrolled fires. The deforestation contribution to carbon emission is already known but determining the contribution of forest degradation remains a challenge. Discrimination of logging from fires, both of which produce different levels of forest damage, is important for the UNFCCC (United Nations Framework Convention on Climate Change) REDD+ (Reducing Emissions from Deforestation and Forest Degradation) program. This work presents a semi-automated procedure for monitoring deforestation and forest degradation in the Brazilian Amazon using fraction images derived from Linear Spectral Mixing Model (LSMM). Part of a Landsat Thematic Mapper (TM) scene (path/row 226/068) covering part of Mato Grosso State in the Brazilian Amazon, was selected to develop the proposed method. First, the approach consisted of mapping deforested areas and mapping forest degraded by fires using image segmentation. Next, degraded areas due to selective logging activities were mapped using a pixel-based classifier. The results showed that the vegetation, soil, and shade fraction images allowed deforested areas to be mapped and monitored and to separate degraded forest areas caused by selective logging and by fires. The comparison of Landsat Operational Land Imager (OLI) and RapidEye results for the year 2013 showed an overall accuracy of 94%. We concluded that spatial resolution plays an important role for mapping selective logging features due to their characteristics. Therefore, when compared to Landsat data, the current availability of higher spatial and temporal resolution data, such as provided by Sentinel-2, is expected to improve the assessment of deforestation and forest degradation, especially caused by selective logging. This will facilitate the implementation of actions for forest protection. 相似文献
129.
Conversion electron Mössbauer spectra revealed that the uppermost surface layer of a carburized and quenched steel was almost -austenite and that the surface layer of this sample consisted of -martensite and -austenite. Iron carbide was expected to have been formed in the surface layer of a carburized and annealed steel but, in fact, no iron carbide could be recognized in the sample. This may be due to the de-carburization or the re-diffusion of carbon into the steel. However, conclusive evidence supporting this explanation was not obtained. 相似文献
130.
Junichi Hojo Kenji Miyachi Yasuzo Okabe Akio Kato 《Journal of the American Ceramic Society》1983,66(7):c114-c115
Ultrafine β-SiC powders with an average particle size of 0.01 to 0.06 μm were produced by CVD methods. When these powders contained enough carbon to remove impurity oxygen, sintered bodies with a relative density >95% were uchieved at 2050°C in the presence of 1 wt% boron. The Vickers microhardness reached 21 to 25 GPa at a density of ∼95% . 相似文献