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771.
Measuring oxygen saturation of skin with advancing age using iterative optical path-length matrix method 总被引:1,自引:1,他引:0
Satoshi Yamamoto Shumpei Watanabe Izumi Fujiwara Norimichi Tsumura Tetsuo Akiba Keiko Ogawa-Ochiai 《Artificial Life and Robotics》2013,18(3-4):165-171
We measured the oxygen saturation of skin at various ages by iterating our previously proposed method that can rapidly simulate skin spectral reflectance with high accuracy. Oxygen saturation is commonly measured by a pulse oximeter to evaluate oxygen delivery for monitoring the functions of heart and lungs at a specific time. On the other hand, oxygen saturation of skin is expected to assess peripheral conditions. Our previously proposed method, the optical path-length matrix method (OPLM), is based on a Monte Carlo model of steady-state light transport in multi-layered tissue (MCML), but can simulate skin spectral reflectance 27,000 times faster than MCML. In this study, we implemented an iterative OPLM with a nonlinear optimization technique such that this method can also be used for estimating hemoglobin concentration and oxygen saturation from the measured skin spectral reflectance. The iterative OPLM was over 25,000 times faster than the MCML with 95 % accuracy. Before measurements in clinic, stability of oxygen saturation among measuring pressure was confirmed. Then, the skin reflectance spectra of 72 outpatients aged between 20 and 86 years were measured by a spectrophotometer. Three points were measured for each subject: the forearm, the thenar eminence, and the intermediate phalanx. The result showed that the oxygen saturation of skin remained constant at each point as the age varied. 相似文献
772.
Forest gap dynamics affects light intensity on the forest floor, which in turn may influence defense and survival of tree
seedlings. Current-year Fagus crenata seedlings show high mortality under the canopy caused by damping-off. In contrast, they survive pathogen attacks in gaps.
However, defense mechanisms against damping-off have not been fully understood. In order to determine the resistance factors
that affect mortality in current-year seedlings, we compared seedling survival and chemical and histological characteristics
of the hypocotyls of seedlings from closed-stand and forest-edge plots. Damping-off occurred in the current-year seedlings
mainly from the end of June to July; survival rate of the seedlings was higher in the forest-edge plot than in the closed-stand
plot. By performing an inoculation test on the seedling hypocotyls, we identified Colletotrichum dematium and Cylindrocarpon sp. as the causative pathogens under low illumination only. In the beginning of July, only seedling hypocotyls from the forest-edge
plot exhibited periderm formation. From mid-June to July, seedling hypocotyls from the forest-edge plot accumulated approximately
twice the amount of total phenols as those accumulated by seedling hypocotyls from the closed-stand plot. The ethyl acetate
phase of methanol extracts of hypocotyls showed antifungal activity. We conclude that seedlings from the forest-edge plot
may resist pathogenic attack via periderm formation and increased phenol synthesis. Plant defense mechanisms that are controlled
by light intensity may be important for promoting seedling regeneration in forest gap dynamics. 相似文献
773.
Xiong-chao Lin Keiko Ideta Jin Miyawaki Hiromichi Takebe Yong-gang Wang Seong-Ho Yoon Isao Mochida 《煤炭学报(英文版)》2012,18(1):80-87
Structural and compositional transitions of Datong coal ash and its CaCO3 additional effects were carefully examined at a temperature range of 300 to 1 600 °C by using XRD and solid state NMR. The
quantitative estimation of amorphous structures of ashes can be successfully obtained through the analyses of solid state
NMR spectra. Viscosity of molten ash and its changes with CaCO3 addition were also evaluated up to 1 700 °C by using a rotary type viscometer. Glasses with poor crystalline and amorphous
phase were continuously formed through the eutectic reaction of silica above fusing temperature (FT>1 500 °C) that caused
broadening and shift of 29Si and 27Al peaks in NMR results. With the additional amount of CaCO3 increasing, the peaks shifted to downfield obviously; the fraction of Si(OAl)0(OSi)4 decreased, while that of Si(OAl)1(OSi)1 at −84.3×10−6 increased apparently. These transitions indicated the destruction of large alumina-silicate framework into small segments
by the addition of Ca ion. 相似文献
774.
Abstract In part I of this investigation it was shown that the phenomenon of correlation-induced spectral changes may be used to construct novel types of spectral filter which could modify the spectrum of the source in any desired manner. In the present paper a method of realizing such filters is described and some of their potential applications are discussed. 相似文献
775.
Shuji Noda Kazuhide Nagano Eiji Inoue Toshio Egi Takeshi Nakashima Naoto Imawaka Masahiro Kanayama Shiro Iwata Kunihiro Toshima Keiko Nakada Katsumi Yoshino 《Synthetic Metals》2009,159(21-22):2355-2357
The DSSC sub-module of 120 mm2 which has high temperature durability was fabricated. The durability was tested under 85 °C for 1000 h; at the end of the test the conversion efficiency was retained over 95% of the initial one. The high temperature durability was realized using the improved sealant, protective material of collecting grids and the new ruthenium-complex dye J2 which was developed by SIIT. By the same way the larger size module was developed. 相似文献
776.
Oxidative stress plays an important role in the pathophysiology of acute kidney injury (AKI). Previously, we reported that vanin-1, which is involved in oxidative stress, is associated with renal tubular injury. This study was aimed to determine whether urinary vanin-1 is a biomarker for the early diagnosis of AKI in two experimental models: in vivo and in vitro. In a rat model of AKI, ischemic AKI was induced in uninephrectomized rats by clamping the left renal artery for 45 min and then reperfusing the kidney. On Day 1 after renal ischemia/reperfusion (I/R), serum creatinine (SCr) in I/R rats was higher than in sham-operated rats, but this did not reach significance. Urinary N-acetyl-β-D-glucosaminidase (NAG) exhibited a significant increase but decreased on Day 2 in I/R rats. In contrast, urinary vanin-1 significantly increased on Day 1 and remained at a significant high level on Day 2 in I/R rats. Renal vanin-1 protein decreased on Days 1 and 3. In line with these findings, immunofluorescence staining demonstrated that vanin-1 was attenuated in the renal proximal tubules of I/R rats. Our in vitro results confirmed that the supernatant from HK-2 cells under hypoxia/reoxygenation included significantly higher levels of vanin-1 as well as KIM-1 and NGAL. In conclusion, our results suggest that urinary vanin-1 might be a potential novel biomarker of AKI induced by I/R. 相似文献
777.
Wataru Hashimoto Keiko Momma Tomoyuki Katsube Yasunobu Ohkawa Teruo Ishige Makoto Kito Shigeru Utsumi Kousaku Murata 《Journal of the science of food and agriculture》1999,79(12):1607-1612
The compositions of transgenic potatoes with intact and modified genes for soybean glycinin were compared with those of control potatoes; non-transgenic or transgenic ones with a vector. The expression levels of glycinin proteins in the transgenic potato tubers were approximately 12–31 mg g−1-total soluble protein. With reference to six major components, moisture, protein, lipid, fiber, ash and carbohydrate, there were no significant differences between transgenic and control potatoes. The levels of glycoalkaloids in transgenic potato tubers, as well as in transgenic controls, increased in comparison with those in non-transgenic ones, though the level was within the permitted limit. The modified glycinin expressed in the transgenic potato tuber was digested under the simulated gastric conditions. From these results, the transgenic potatoes with intact and modified glycinin genes are considered to be as safety utilization for food as non-transgenic potatoes. © 1999 Society of Chemical Industry 相似文献
778.
Isao Hasegawa Yoshiaki Fujii Keiko Yamada Chieko Kariya Toshio Takayama 《应用聚合物科学杂志》1999,73(7):1321-1328
Lignin, prepared by digesting cedar with acetic acid, and tetraethoxysilane have been allowed for a sol–gel reaction in tetrahydrofuran using H2SO4 as catalyst to yield lignin–SiO2 hybrids in the bulk gel form. The solid-state 13C nuclear magnetic resonance spectra of the hybrids and products formed solely from the lignin under the acidic conditions revealed that the lignin underwent crosslinking during the sol–gel reaction. The degree of crosslinking increased with an increasing amount of H2SO4. The powdered hybrids have been heated at 1500°C in Ar for carbothermal reduction, resulting in the formation of SiC powders. The lignin-to-tetraethoxysilane mixing ratio of the starting solutions varied free carbon content in the SiC powders. In addition, the amount of carbonaceous residue formed from the lignin upon heating depended on the degree of crosslinking of the lignin. Thus, to adjust the amounts of both the lignin and H2SO4 was necessary for producing the hybrids suitable for precursors for SiC powders with high purity. Critical adjustment of the amounts led to the formation of SiC powders with a free carbon content of 0.57 wt %, implying that the lignin is a beneficial carbon source for the production of SiC powders by the hybrid route. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 1321–1328, 1999 相似文献
779.
As cellulose triacetate was prepared from low-grade hardwood-dissolving pulp, a considerable amount of the insoluble residue was present in the acetylation medium of the acetic acid/acetic anhydride/sulfuric acid system, and it consisted mainly of cellulose triacetate (CTA) and xylan diacetate (XDA). As one of the remedies for reducing the insoluble residue, a solvent was added to the acetylation medium and the effects of the solvent addition on the amount of insoluble residue formed were studied. To do so, 17 different solvents were selected so as to cover a wide range of solubility parameters. The obtained results clearly indicated that the addition of the solvent affects the amount of insoluble residue and that, excluding dichloroacetic acid, nitromethane was effective for its reduction, but that neither methylene chloride nor nitroethane were in spite of their effectiveness for softwood-dissolving pulp, which would be due to the intrinsic properties of XDA on the solubility in the acetylation medium. A new acetylation system with such an appropriate solvent would, therefore, provide a clue as to an industrial usage of the low-grade hardwood-dissolving pulps for cellulose acetate production. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 1445–1449, 1998 相似文献
780.
Toshiyuki Kondo Akio Ishiguro Yuji Watanabe Yasuhiro Shirai Yoshiki Uchikawa 《Electrical Engineering in Japan》1998,123(3):1-10
In recent years, in the field of artificial intelligence (AI), much attention has been focused on reactive planning approaches such as behavior-based AI and new AI. However, a criticism of these approaches is that their arbitration among competence modules is fixed against dynamically changing environments. On the other hand, biological information processing systems have various interesting characteristics from an engineering viewpoint. Among them, the immune system plays an important role in maintaining its own system against dynamically changing environments. Based on this fact, we have investigated a new decentralized consensus-making system for the behavior arbitration of autonomous mobile robots, inspired by the idiotypic network hypothesis in immunology. In this paper, we illustrate the usefulness of our proposed method by means of computer simulations and experiments. © 1998 Scripta Technica. Electr Eng Jpn, 123(3): 1–10, 1998 相似文献