全文获取类型
收费全文 | 1045篇 |
免费 | 35篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 65篇 |
化学工业 | 261篇 |
金属工艺 | 21篇 |
机械仪表 | 24篇 |
建筑科学 | 31篇 |
能源动力 | 79篇 |
轻工业 | 114篇 |
水利工程 | 2篇 |
无线电 | 76篇 |
一般工业技术 | 167篇 |
冶金工业 | 72篇 |
原子能技术 | 51篇 |
自动化技术 | 118篇 |
出版年
2024年 | 4篇 |
2023年 | 11篇 |
2022年 | 19篇 |
2021年 | 37篇 |
2020年 | 22篇 |
2019年 | 16篇 |
2018年 | 24篇 |
2017年 | 19篇 |
2016年 | 23篇 |
2015年 | 23篇 |
2014年 | 34篇 |
2013年 | 77篇 |
2012年 | 53篇 |
2011年 | 92篇 |
2010年 | 66篇 |
2009年 | 58篇 |
2008年 | 45篇 |
2007年 | 55篇 |
2006年 | 42篇 |
2005年 | 36篇 |
2004年 | 27篇 |
2003年 | 24篇 |
2002年 | 36篇 |
2001年 | 16篇 |
2000年 | 13篇 |
1999年 | 17篇 |
1998年 | 34篇 |
1997年 | 30篇 |
1996年 | 12篇 |
1995年 | 13篇 |
1994年 | 11篇 |
1993年 | 13篇 |
1992年 | 5篇 |
1991年 | 8篇 |
1990年 | 7篇 |
1989年 | 10篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1983年 | 5篇 |
1982年 | 4篇 |
1980年 | 6篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1974年 | 3篇 |
1972年 | 2篇 |
排序方式: 共有1081条查询结果,搜索用时 678 毫秒
41.
Junji Fukuda Shintaro Takahashi Tatsuya Osaki Naoto Mochizuki Hiroaki Suzuki 《Science and Technology of Advanced Materials》2012,13(6)
Plugs, i.e. droplets formed in a microchannel, may revolutionize microfluidic cell-based assays. This study describes a microdevice that handles nanolitre-scale liquid plugs for the preparation of various culture setups and subsequent cellular assays. An important feature of this mode of liquid operation is that the recirculation flow generated inside the plug promotes the rapid mixing of different solutions after plugs are merged, and it keeps cell suspensions homogeneous. Thus, serial dilutions of reagents and cell suspensions with different cell densities and cell types were rapidly performed using nanolitres of solution. Cells seeded through the plug processing grew well in the microdevice, and subsequent plug processing was used to detect the glucose consumption of cells and cellular responses to anticancer agents. The plug-based microdevice may provide a useful platform for cell-based assay systems in various fields, including fundamental cell biology and drug screening applications. 相似文献
42.
Takuya Morikawa Tatsuya Ashitani Hisayoshi Kofujita Koetsu Takahashi 《Holz als Roh- und Werkstoff》2014,72(5):651-657
The antitermitic activity of extracts from the branch heartwood of Chamaecyparis obtusa (hinoki) against Japanese termites (Reticulitermes speratus) was compared with that of the trunk. Samples of branch and trunk heartwood were extracted with n-hexane, ethyl acetate, and methanol successively. n-Hexane extracts of branch and trunk heartwood were strongly antitermitic, and branch heartwood contained greater quantities of active n-hexane extracts than trunk heartwood. Germacra-1-(10), 5-dien-4β-ol, t-cadinol, α-cadinol, hinokiresinol, and hinokinin were separated from the branch extracts and the termiticidal and antifeedant activity of these compounds was tested by no-choice and dual-choice test methods. The sesquiterpenoids, germacra-1-(10), 5-dien-4β-ol, t-cadinol and α-cadinol were strongly termiticidal. The norlignan hinokiresinol and lignan hinokinin had weak termiticidal, and strong antifeedant and repellent activity. High concentrations of germacra-1-(10), 5-dien-4β-ol and hinokiresinol were present in branch heartwood. These compounds protect hinoki branches from termites and other harmful organisms. Hinoki branch heartwood, which is usually unused, is a potential source of active antitermitic compounds. 相似文献
43.
Jingyu Xiang Yuichi Tazaki Shinkichi Inagaki Tatsuya Suzuki 《Electrical Engineering in Japan》2014,186(4):59-69
This paper presents a method that allows simultaneous map building and path planning for mobile robots in unknown environments. A graphical representation of a workspace in variable resolutions is constructed using measurement data obtained by omnidirectional distance sensors. At the same time, a search for a feasible path to the target destination is executed using the constructed graph map. The proposed method is evaluated by performing simulations and experiments using an omnidirectional mobile robot equipped with laser range finders. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(4): 59–69, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22493 相似文献
44.
45.
46.
Wataru Kanematsu Tatsuya Miyajima Mutsuo Sando 《Journal of the American Ceramic Society》2001,84(10):2427-2429
A visualizing technique for indentation damage of ceramics was developed. Plasma etching was used to enhance the view of cracks and the subsurface microcracking crush zone following Knoop indentation of hot pressed Si3 N4 . The microcracking zone was readily identified from the surface view of the indented surface as a grain-falling-off region (GFOR), defined as a region in which grains were removed by preferential etching using CF4 gas, followed by ultrasonic cleaning. A fissure-like opening corresponding to the indentation cracks was also observed. It is inferred that the formation of the GFOR region and the fissure-like opening were caused by the etching/cleaning treatment. Meanwhile, the etching on a section which included diagonals of the impression provided a section view of the microcracking zone. 相似文献
47.
所谓“疏散地形时间地图”(一般叫逃生地图)是指从绘制详细的疏散地图到致力于震后重建方法论的一系列举措。这一系列举措不仅保护了众多今后可能会没落的地域文化。而且还从地震中吸取教训,在进行建设和规划以人命优先为主旨的城市的前提下尝试着对地域进行改变。本文主要介绍了“逃生地图”概要、地方研讨会的地图效果以及逃生地图在汽车导航服务方面的应用等。 相似文献
48.
Toshiki Ozaki Tatsuya KotoTam V. Nguyen Hideyuki NakanishiTomohisa Norisuye Qui Tran-Cong-Miyata 《Polymer》2014
Influence of the Trommsdorff–Norrish (T–N) effect on the phase separation of methyl methacrylate (MMA)/poly(ethyl acrylate) (PEA) mixtures undergoing photo-polymerization was examined by a combination of several experimental techniques. By FT-IR spectroscopy, it was found that the polymerization conversion explosively increases at the onset of this T–N effect. The characteristic irradiation time τ at which this effect occurs, strongly depends on the light intensity and gradually shifts to early time as the irradiation intensity increases. The shrinkage of the mixture observed in situ by laser-scanning confocal microscopy exhibits a transition at a particular irradiation time which is slightly longer than the characteristic time τ. By gel permeation chromatography (GPC), it was found that the molecular weight of the resulting PMMA was almost unchanged before τ and suddenly increases about an order of magnitude after the onset of the auto-acceleration effect. Finally, the characteristic length scales of the morphology also quickly increase with irradiation time and are eventually frozen by this T–N effect. These experimental results indicate that the Trommsdorff–Norrish effect plays an important role in the kinetic processes of polymerization-induced phase separation, suggesting an efficient tool to control the morphology of the polymerizing mixture. 相似文献
49.
Yuji Higaki Ryosuke Okazaki Tatsuya Ishikawa Moriya Kikuchi Noboru Ohta Atsushi Takahara 《Polymer》2014
The chain stiffness and local chain conformation of atactic poly(α-methylene-γ-butyrolactone) (PMBL), which is a side chain cyclic structural analog of poly(methyl methacrylate) (PMMA), with a weight-average molecular weight (Mw) ranging from 2.8 × 103 to 2.6 × 106 in N,N-dimethylformamide (DMF) and γ-butyrolactone (GBL) were characterized by size exclusion chromatography with a multi-angle light-scattering detector (SEC-MALS) and synchrotron radiation small-angle X-ray scattering (SAXS). Based on the Kratky-Porod worm-like chain model, the scattering functions and the Mw dependence of z-average root-mean-square radius of gyration <S2>z1/2 yielded the Kuhn segment lengths λ−1, the diameter of the PMBL chains d, and the excluded-volume strengths in DMF and GBL. The local conformation of atactic PMBL in DMF and GBL were slightly larger than those of atactic PMMA, due to the presence of the conformationally rigid lactone ring structure. 相似文献
50.
Tae Oike Yoshihito Sekiguchi Yuya Yoshimoto Takahiro Oike Ken Ando Wenchao Gu Yasushi Sasaki Takashi Tokino Akira Iwase Tatsuya Ohno 《International journal of molecular sciences》2022,23(1)
Radiotherapy is a definitive treatment for early-stage cervical cancer; however, a subset of this disease recurs locally, necessitating establishment of predictive biomarkers and treatment strategies. To address this issue, we performed gene panel-based sequencing of 18 stage IB cervical cancers treated with definitive radiotherapy, including two cases of local recurrence, followed by in vitro and in silico analyses. Simultaneous mutations in KRAS and SMAD4 (KRASmt/SMAD4mt) were detected only in a local recurrence case, indicating potential association of this mutation signature with radioresistance. In isogenic cell-based experiments, a combination of activating KRAS mutation and SMAD4 deficiency led to X-ray resistance, whereas either of these factors alone did not. Analysis of genomic data from 55,308 cancers showed a significant trend toward co-occurrence of mutations in KRAS and SMAD4. Gene Set Enrichment Analysis of the Cancer Cell Line Encyclopedia dataset suggested upregulation of the pathways involved in epithelial mesenchymal transition and inflammatory responses in KRASmt/SMAD4mt cancer cells. Notably, irradiation with therapeutic carbon ions led to robust killing of X-ray-resistant KRASmt/SMAD4mt cancer cells. These data indicate that the KRASmt/SMAD4mt signature is a potential predictor of radioresistance, and that carbon ion radiotherapy is a potential option to treat early-stage cervical cancers with the KRASmt/SMAD4mt signature. 相似文献