全文获取类型
收费全文 | 873篇 |
免费 | 38篇 |
国内免费 | 14篇 |
专业分类
电工技术 | 34篇 |
综合类 | 62篇 |
化学工业 | 120篇 |
金属工艺 | 9篇 |
机械仪表 | 64篇 |
建筑科学 | 278篇 |
矿业工程 | 7篇 |
能源动力 | 18篇 |
轻工业 | 39篇 |
水利工程 | 4篇 |
石油天然气 | 25篇 |
武器工业 | 8篇 |
无线电 | 62篇 |
一般工业技术 | 29篇 |
冶金工业 | 6篇 |
原子能技术 | 12篇 |
自动化技术 | 148篇 |
出版年
2023年 | 5篇 |
2022年 | 14篇 |
2021年 | 13篇 |
2020年 | 15篇 |
2019年 | 11篇 |
2018年 | 5篇 |
2017年 | 19篇 |
2016年 | 28篇 |
2015年 | 25篇 |
2014年 | 54篇 |
2013年 | 47篇 |
2012年 | 50篇 |
2011年 | 61篇 |
2010年 | 60篇 |
2009年 | 65篇 |
2008年 | 60篇 |
2007年 | 55篇 |
2006年 | 67篇 |
2005年 | 67篇 |
2004年 | 60篇 |
2003年 | 40篇 |
2002年 | 29篇 |
2001年 | 16篇 |
2000年 | 13篇 |
1999年 | 11篇 |
1998年 | 14篇 |
1997年 | 6篇 |
1996年 | 3篇 |
1995年 | 4篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1989年 | 1篇 |
1985年 | 1篇 |
1982年 | 1篇 |
1980年 | 3篇 |
排序方式: 共有925条查询结果,搜索用时 46 毫秒
41.
Martina Decker 《Architectural Design》2016,86(1):82-87
At best, the ageing of materials is regarded as lending a patina to historic buildings. In reality, however, materials often age disgracefully and unevenly, requiring a high level of maintenance and refurbishment. What if materials could be engineered and integrated into buildings not only to enhance but to heal? Martina Decker , Assistant Professor in the College of Architecture and Design at the New Jersey Institute of Technology (NJIT), looks at pioneering research that is being undertaken into performative, time-dependent materials. 相似文献
42.
Branko Kolarevic 《Architectural Design》2015,85(5):128-133
An emphasis on material synthesis is not without its pitfalls and challenges. Here Branko Kolarevic , Professor and Chair in Integrated Design at the University of Calgary Faculty of Environmental Design, alerts us to the dangers of overlooking materials' shifting capacities, which are so often scale dependent, while also disregarding existing materials in favour of the new or novel. As the potential grows for material systems in buildings to become more adaptive and to harness automation, Kolarevic describes some exciting developments that are taking place in dynamic facade design, providing the much-heralded promise of an efficient use of ambient energy. 相似文献
43.
Alex McDowell 《Architectural Design》2015,85(4):26-33
Film production requires world building: the power to visualise and bring to life narrative through a film's total environment. This is often entirely speculative, imagining alternative or future worlds. Here, Alex McDowell , acclaimed British production designer, producer and Professor at the University of Southern California (USC) describes his world-building, narrative approach to production design, which he consolidated in the Steven Spielberg film Minority Report (2002) that envisioned Washington DC in the year 2050. The possibilities of this storytelling technique are demonstrated by its transference into real-life projects, such as the immersive model that his production company, 5D GlobalStudio, developed for Al Baydha, a Bedouin village in Saudi Arabia. 相似文献
44.
利用Virtual Lab Motion对下肢外骨骼进行了结构建模。依据现有的临床步态分析数据——关节角度随时间的变化关系,通过运动学分析逆向得出所设计系统各个液压缸的理想控制曲线,即液压缸位移随时间的变化关系。依据仿真得到的力臂及液压缸速度可对电液系统的压力和流量进行估算,利用Virtual Lab Motion与AMESim的耦合仿真验证了系统的合理性。 相似文献
45.
A novel vinyl ether-type RAFT agent, benzyl 2-(vinyloxy)ethyl carbonotrithioate (BVCT) was synthesized for various block copolymers via the combination of living cationic polymerization of vinyl ethers and reversible addition−fragmentation chain transfer (RAFT) polymerization. The novel BVCT–trifluoroacetic acid adduct play an important role to produce well-defined block copolymers, which is both as a cationogen under EtAlCl2 initiation system in the presence of ethyl acetate for living cationic polymerization and a RAFT agent for blocks by RAFT polymerization. The resulting polymer, poly(vinyl ether)s, by living cationic polymerization had a high number average α-end functionality (≥0.9) as determined by both 1H NMR and MALDI-TOF-MS spectrometry. In addition, this poly(vinyl ether)s worked well as a macromolecular chain transfer agent for RAFT polymerization. The RAFT polymerization of radically polymerizable monomers was conducted in toluene using 2,2′-azobis(isobutyronitrile) at 70 °C. For example, a double thermoresponsive block copolymer (MOVE61-b-NIPAM150) consisting of 2-methoxyethyl vinyl ether (MOVE) and N-isopropylacrylamide (NIPAM) was prepared via the combination of living cationic polymerization and RAFT polymerization. The block copolymer reversibly formed and deformed micellar assemblies above the phase separation temperature (Tps) of poly(NIPAM) block in water. This BVCT is not only functioned as an initiator, but also acted as a monomer. When BVCT was copolymerized with MOVE by living cationic polymerization, followed by graft copolymerization with NIPAM via RAFT polymerization, well-defined graft copolymers (MOVEn-co-BVCTm)-g-NIPAMx (n = 62–73, m = 1–9, x = 19–214) were successfully obtained. However, no micelle formed in water above Tps of poly(NIPAM) graft chain unlike the case of block copolymers. 相似文献
46.
The controlled synthesis of narrowly distributed low molecular weight polymers with functionalization possibilities is of great industrial interests. Although living polymerization allows for control over polymer architecture, the production of low molecular weight polymers with low polydispersities via living polymerization systems is challenged by the use of large amounts of catalysts and broadening in molecular weight distribution. This review addresses the synthesis of narrowly distributed, functional, low molecular weight polyethylene and polyethylene mimics. The review is structured for quick identification of relevant systems for the production of specific polymer architectures with specific cost, efficiency, and safety concerns. 相似文献
47.
食品香精是加香产品的“灵魂”,是食品添加剂的重要组成部分。近年来我国食品香精呈现良好的发展势头,本文对当前食品香精研究开发的热点作了综述,并指出了未来的研究开发前景。 相似文献
48.
Kiyotaka Onitsuka Atsushi Shimizu Fumie Takei Shigetoshi Takahashi 《Journal of Inorganic and Organometallic Polymers and Materials》2009,19(1):98-103
A novel multifunctional initiator has been developed by peripheral modification of a Pt-acetylide dendrimer. Pd–Pt μ-ethynediyl
units were introduced to the first-generation dendrimer by a divergent method. The dendritic initiator was applicable to the
living polymerization of aryl isocyanides, producing high molecular weight polymers with a narrow polydispersity index in
quantitative yields. The 31P NMR spectrum of the resulting polymer suggested that all Pd–Pt μ-ethynediyl units in the dendritic molecule actually functioned
as an initiator. 相似文献
49.
50.
随着城市建设的发展,传统公园的改造面临着巨大的挑战,本文以西湖公园改造更新项目为例,分析目前传统公园改造存在的主要问题,运用人居环境科学理论以及"有机更新"的设计理念,提出了针对城市传统公园的改造原则和改造策略,在尽可能满足现代功能要求的同时,保护公园的传统文化与景观特色,打造具有艺术性、文化性与功能性的公园景观,体现可持续、科学的发展观。 相似文献