全文获取类型
收费全文 | 358篇 |
免费 | 3篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 35篇 |
综合类 | 3篇 |
化学工业 | 134篇 |
金属工艺 | 5篇 |
机械仪表 | 6篇 |
建筑科学 | 7篇 |
能源动力 | 10篇 |
轻工业 | 33篇 |
水利工程 | 4篇 |
石油天然气 | 1篇 |
无线电 | 22篇 |
一般工业技术 | 61篇 |
冶金工业 | 13篇 |
原子能技术 | 9篇 |
自动化技术 | 19篇 |
出版年
2024年 | 1篇 |
2023年 | 1篇 |
2022年 | 6篇 |
2021年 | 11篇 |
2020年 | 4篇 |
2019年 | 1篇 |
2018年 | 3篇 |
2017年 | 3篇 |
2016年 | 6篇 |
2015年 | 2篇 |
2014年 | 6篇 |
2013年 | 16篇 |
2012年 | 12篇 |
2011年 | 23篇 |
2010年 | 6篇 |
2009年 | 8篇 |
2008年 | 27篇 |
2007年 | 20篇 |
2006年 | 14篇 |
2005年 | 21篇 |
2004年 | 18篇 |
2003年 | 18篇 |
2002年 | 15篇 |
2001年 | 4篇 |
2000年 | 12篇 |
1999年 | 8篇 |
1998年 | 8篇 |
1997年 | 10篇 |
1996年 | 5篇 |
1995年 | 8篇 |
1994年 | 6篇 |
1993年 | 9篇 |
1992年 | 6篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1985年 | 5篇 |
1984年 | 9篇 |
1983年 | 1篇 |
1982年 | 5篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1973年 | 1篇 |
排序方式: 共有362条查询结果,搜索用时 15 毫秒
351.
352.
Ioannis K. Brilakis Lucio Soibelman Yoshihisa Shinagawa 《Advanced Engineering Informatics》2006,20(4):443-452
The capability to automatically identify shapes, objects and materials from the image content through direct and indirect methodologies has enabled the development of several civil engineering related applications that assist in the design, construction and maintenance of construction projects. This capability is a product of the technological breakthroughs in the area of image processing that has allowed for the development of a large number of digital imaging applications in all industries. In this paper, an automated and content based construction site image retrieval method is presented. This method is based on image retrieval techniques, and specifically those related with material and object identification and matches known material samples with material clusters within the image content. The results demonstrate the suitability of this method for construction site image retrieval purposes and reveal the capability of existing image processing technologies to accurately identify a wealth of materials from construction site images. 相似文献
353.
Keisuke Kojima Naoki Sunagawa Yoshihisa Yoshimi Theodora Tryfona Masahiro Samejima Paul Dupree Kiyohiko Igarashi 《Journal of Applied Glycoscience》2022,69(2):35
Endo-type xylanases are key enzymes in microbial xylanolytic systems, and xylanases belonging to glycoside hydrolase (GH) families 10 or 11 are the major enzymes degrading xylan in nature. These enzymes have typically been characterized using xylan prepared by alkaline extraction, which removes acetyl sidechains from the substrate, and thus the effect of acetyl groups on xylan degradation remains unclear. Here, we compare the ability of GH10 and 11 xylanases, PcXyn10A and PcXyn11B, from the white-rot basidiomycete Phanerochaete chrysosporium to degrade acetylated and deacetylated xylan from various plants. Product quantification revealed that PcXyn10A effectively degraded both acetylated xylan extracted from Arabidopsis thaliana and the deacetylated xylan obtained by alkaline treatment, generating xylooligosaccharides. In contrast, PcXyn11B showed limited activity towards acetyl xylan, but showed significantly increased activity after deacetylation of the xylan. Polysaccharide analysis using carbohydrate gel electrophoresis showed that PcXyn11B generated a broad range of products from native acetylated xylans extracted from birch wood and rice straw, including large residual xylooligosaccharides, while non-acetylated xylan from Japanese cedar was readily degraded into xylooligosaccharides. These results suggest that the degradability of native xylan by GH11 xylanases is highly dependent on the extent of acetyl group substitution. Analysis of 31 fungal genomes in the Carbohydrate-Active enZymes database indicated that the presence of GH11 xylanases is correlated to that of carbohydrate esterase (CE) family 1 acetyl xylan esterases (AXEs), while this is not the case for GH10 xylanases. These findings may imply co-evolution of GH11 xylanases and CE1 AXEs. 相似文献
354.
Reconstruction of bone fenestration on mandiblar by the guided bone regeneration methods with beta-TCP/PLGC membranes 总被引:1,自引:0,他引:1
Koyama Y Kikuchi M Edamura K Nagaoka K Tanaka S Tanaka J Takakuda K 《Journal of nanoscience and nanotechnology》2007,7(3):859-861
Guided Bone Regeneration (GBR) is a method for bone tissue regeneration. In this method, membranes are used to cover bone defects and to block the invasion of the surrounding soft tissues. It would provide sufficient time for the osteogenic cells from bone marrow to proliferate and form new bony tissues. In spite of the potential usefulness of this method, no appropriate materials for the GBR membrane have been developed. Here we design the ideal mechanical properties of the GBR membranes and created novel materials, which is the composite of beta-tricalcium phosphate (beta-TCP) and block copolymer of L-lactide, glycolide, and epsilon-caplolactone (PLGC). In the animal experiments with the use of the GBR membranes for large bone defects, we observed significant enhancement in the bone regeneration after 12 weeks implantation and proved the effectiveness of the materials. 相似文献
355.
Alteration of Wax Ester Content and Composition in Euglena gracilis with Gene Silencing of 3‐ketoacyl‐CoA Thiolase Isozymes 下载免费PDF全文
Masami Nakazawa Hiroko Andoh Keiichiro Koyama Yomi Watanabe Takeo Nakai Mitsuhiro Ueda Tatsuji Sakamoto Hiroshi Inui Yoshihisa Nakano Kazutaka Miyatake 《Lipids》2015,50(5):483-492
Euglena gracilis produces wax ester under hypoxic and anaerobic culture conditions with a net synthesis of ATP. In wax ester fermentation, fatty acids are synthesized by reversing beta‐oxidation in mitochondria. A major species of wax ester produced by E. gracilis is myristyl myristate (14:0‐14:0Alc). Because of its shorter carbon chain length with saturated compounds, biodiesel produced from E. gracilis wax ester may have good cold flow properties with high oxidative stability. We reasoned that a slight metabolic modification would enable E. gracilis to produce a biofuel of ideal composition. In order to produce wax ester with shorter acyl chain length, we focused on isozymes of the enzyme 3‐ketoacyl‐CoA thiolase (KAT), a condensing enzyme of the mitochondrial fatty acid synthesis pathway in E. gracilis. We performed a gene silencing study of KAT isozymes in E. gracilis. Six KAT isozymes were identified in the E. gracilis EST database, and silencing any three of them (EgKAT1‐3) altered the wax ester amount and composition. In particular, silencing EgKAT1 induced a significant compositional shift to shorter carbon chain lengths in wax ester. A model fuel mixture inferred from the composition of wax ester in EgKAT1‐silenced cells showed a significant decrease in melting point compared to that of the control cells. 相似文献
356.
Akiyama H Nakamura K Harikai N Watanabe H Iijima K Yamakawa H Mizuguchi Y Yoshikawa R Yamamoto M Sato H Watai M Arakawa F Ogasawara T Nishihara R Kato H Yamauchi A Takahata Y Morimatsu F Mamegoshi S Muraoka S Honjoh T Watanabe T Sakata K Imamura T Toyoda M Matsuda R Maitani T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2004,45(6):325-331
Inter-laboratory evaluation studies were conducted for ELISA methods for allergic substances (peanuts). Extracts of biscuit, sauce, chocolate and butter spiked with peanut standard protein at a level of 5-20 ng/mL as sample solutions were analyzed in replicate in 10 laboratories. Coefficients of variation (CVs) of the ELISA methods using a Peanut Protein ELISA Kit (Peanut kit) and a FASTKIT Peanut ELISA kit (Peanut ELISA kit) were mostly below 10%. Mean recoveries of the peanut standard protein from the food extracts were over 40% in the two ELISA methods. Repeatability relative standard deviations of peanut standard protein in four food extracts were in the ranges of 15.2-49.7% and 3.0-28.3% for the Peanut kit and the Peanut ELISA kit, respectively. Reproducibility relative standard deviations of peanut standard protein in four food extracts were 23.5-44.4%, 9.6-28.4% for the Peanut kit and the Peanut ELISA kit, respectively. The detection limits of both ELISA methods were 2-2.5 ng/mL in sample solutions. These results suggested that the notified ELISA methods are reliable and reproducible for the inspection of peanut protein levels in extracts of biscuit, sauce, chocolate and butter. 相似文献
357.
Electric vehicles are expected to be one of the means to level the difference between the peak time and off-peak time electric loads. From a global point of view, increasing environmental concerns make us recognize the necessity of replacing conventional gasoline cars by electric vehicles. Due to problems with the efficiency and life time of a battery, it will take time before electric vehicles are in general use. Electric vehicles are used only in specialized small fields. Automobile makers are cooperating to invent advanced batteries for use in electric vehicle. Thus, it is timely to develop appropriate infrastructure standards and technologies to make electric vehicles attractive to consumers. In this paper, we investigate the impact of electric vehicle on electricity demands by assuming analytical models of EV consumption. The charging characteristics of a battery, the running performance, and the practical driving distance of each type of car are used in this analysis. According to the scenario analysis, the simulations clearly presented the impact of EV introduction using the practical day load duration curve for the Tokyo cosmopolitan area. The authors conclude that electric vehicles are effective for load leveling under some sort of market regulations. If there is no regulation in the EV market, power shortage will occur on both nighttime and daytime because of the concentration of the nighttime charge and the quick charge. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 120(4): 40–47, 1997 相似文献
358.
Junji Kondoh Takashi Fujita Hiroaki Tsutsui Yoshihisa Sato Shunji Tsuji‐Iio Ryuichi Shimada 《Electrical Engineering in Japan》2000,130(3):39-48
High field is very favorable for magnetically confined fusion devices such as a tokamak, but electromagnetic force derived from the field becomes a fatal problem. In particular, the largest in‐plane centering force hinders toroidal field coils from operating at higher fields. Variable pitch multihelical coils, which we term force‐balanced coils (FBCs), by which this force is drastically reduced, are proposed for the coil system of tokamaks. FBCs can also provide poloidal flux swing for plasma breakdown and current induction during the ramp‐up phase of the coil current. In this paper, we indicate how to design FBCs for tokamaks. The fusion reactor‐size FBCs are designed and compared with that of the conventional toroidal field coil system. © 1999 Scripta Technica, Electr Eng Jpn, 130(3): 39–48, 2000 相似文献
359.
Fahima Khatun Yoshihisa Aizu Izumi Nishidate 《International journal of molecular sciences》2021,22(4)
Cyanosis is a pathological condition that is characterized by a bluish discoloration of the skin or mucous membranes. It may result from a number of medical conditions, including disorders of the respiratory system and central nervous system, cardiovascular diseases, peripheral vascular diseases, deep vein thrombosis, and regional ischemia. Cyanosis can also be elicited from methemoglobin. Therefore, a simple, rapid, and simultaneous monitoring of changes in oxygenated hemoglobin and deoxygenated hemoglobin is useful for protective strategies against organ ischemic injury. We previously developed a red-green-blue camera-based spectral imaging method for the measurements of melanin concentration, oxygenated hemoglobin concentration (CHbO), deoxygenated hemoglobin concentration (CHbR), total hemoglobin concentration (CHbT) and tissue oxygen saturation (StO2) in skin tissues. We leveraged this approach in this study and extended it to the simultaneous quantifications of methemoglobin concentration (CmetHb), CHbO, CHbR, and StO2. The aim of the study was to confirm the feasibility of the method to monitor CmetHb, CHbO, CHbR, CHbT, and StO2. We performed in vivo experiments using rat dorsal skin during methemoglobinemia induced by the administration of sodium nitrite (NaNO2) and changing the fraction of inspired oxygen (FiO2), including normoxia, hypoxia, and anoxia. Spectral diffuse reflectance images were estimated from an RGB image by the Wiener estimation method. Multiple regression analysis based on Monte Carlo simulations of light transport was used to estimate CHbO, CHbR, CmetHb, CHbT, and StO2. CmetHb rapidly increased with a half-maximum time of less than 30 min and reached maximal values nearly 60 min after the administration of NaNO2, whereas StO2 dramatically dropped after the administration of NaNO2, indicating the temporary production of methemoglobin and severe hypoxemia during methemoglobinemia. Time courses of CHbT and StO2, while changing the FiO2, coincided with well-known physiological responses to hyperoxia, normoxia, and hypoxia. The results indicated the potential of this method to evaluate changes in skin hemodynamics due to loss of tissue viability and vitality. 相似文献
360.
Sotaro Motoi Mai Uesugi Takashi Obara Katsuhiro Moriya Yoshihisa Arita Hideaki Ogasawara Motohiro Soejima Toshio Imai Tetsu Kawano 《International journal of molecular sciences》2021,22(9)
Background: Hepatocyte growth factor (HGF) is an endogenously induced bioactive molecule that has strong anti-apoptotic and tissue repair activities. In this research, we identified APOA4 as a novel pharmacodynamic (PD) marker of the recombinant human HGF (rh-HGF), E3112. Methods: rh-HGF was administered to mice, and their livers were investigated for the PD marker. Candidates were identified from soluble proteins and validated by using human hepatocytes in vitro and an animal disease model in vivo, in which its c-Met dependency was also ensured. Results: Among the genes induced or highly enhanced after rh-HGF exposure in vivo, a soluble apolipoprotein, Apoa4, was found to be induced by rh-HGF in the murine liver. By using primary cultured human hepatocytes, the significant induction of human APOA4 was observed at the mRNA and protein levels, and it was inhibited in the presence of a c-Met inhibitor. Although mice constitutively expressed Apoa4 mRNA in the small intestine and the liver, the liver was the primary organ affected by administered rh-HGF to strongly induce APOA4 in a dose- and c-Met-dependent manner. Serum APOA4 levels were increased after rh-HGF administration, not only in normal mice but also in anti-Fas-induced murine acute liver failure (ALF), which confirmed the pharmacodynamic nature of APOA4. Conclusions: APOA4 was identified as a soluble PD marker of rh-HGF with c-Met dependency. It should be worthwhile to clinically validate its utility through clinical trials with healthy subjects and ALF patients. 相似文献