首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   396篇
  免费   30篇
  国内免费   1篇
电工技术   12篇
综合类   3篇
化学工业   137篇
金属工艺   7篇
机械仪表   5篇
建筑科学   18篇
矿业工程   1篇
能源动力   22篇
轻工业   21篇
水利工程   1篇
无线电   39篇
一般工业技术   94篇
冶金工业   3篇
自动化技术   64篇
  2024年   1篇
  2023年   27篇
  2022年   31篇
  2021年   44篇
  2020年   29篇
  2019年   38篇
  2018年   19篇
  2017年   17篇
  2016年   26篇
  2015年   12篇
  2014年   14篇
  2013年   22篇
  2012年   22篇
  2011年   21篇
  2010年   14篇
  2009年   19篇
  2008年   12篇
  2007年   7篇
  2006年   3篇
  2005年   6篇
  2004年   5篇
  2002年   1篇
  2001年   1篇
  2000年   1篇
  1999年   2篇
  1997年   4篇
  1996年   3篇
  1995年   2篇
  1994年   1篇
  1993年   1篇
  1992年   1篇
  1991年   1篇
  1989年   1篇
  1985年   1篇
  1981年   2篇
  1980年   6篇
  1979年   2篇
  1978年   3篇
  1936年   1篇
  1928年   1篇
  1926年   3篇
排序方式: 共有427条查询结果,搜索用时 11 毫秒
51.
52.
The partitioning of corrosion inhibitor (CI) products is a measure of their potential to protect oilfield pipelines. In this paper the hydrophilic–lipophilic deviation (HLD) model is first used to quantify their partitioning in terms of the characteristic curvature (C c,act) of a series of anionic (alkoxylated phosphate esters) and cationic (alkoxylated amines, aromatic amines, imidazoline acetates and quaternary amines) actives. This parameter is expressed over a range of pHs within which pipeline corrosion occurs. The HLD model is next used to predict the partitioning of each active from water into toluene at increased salinities. Linear mixing rules are lastly used to predict the characteristic curvature of Product A (C c,mix) as a function of the C c,act of a subset of actives.  相似文献   
53.
Glioblastoma (GBM) is an obligatory lethal brain tumor with a median survival, even with the best standard of care therapy, of less than 20 months. In light of this fact, the evaluation of new GBM treatment approaches such as oncolytic virotherapy (OVT) is urgently needed. Based on our preliminary preclinical data, the YB-1 dependent oncolytic adenovirus (OAV) XVir-N-31 represents a promising therapeutic agent to treat, in particular, therapy resistant GBM. Preclinical studies have shown that XVir-N-31 prolonged the survival of GBM bearing mice. Now using an immunohumanized mouse model, we examined the immunostimulatory effects of XVir-N-31 in comparison to the wildtype adenovirus (Ad-WT). Additionally, we combined OVT with the inhibition of immune checkpoint proteins by using XVir-N-31 in combination with nivolumab, or by using a derivate of XVir-N-31 that expresses a PD-L1 neutralizing antibody. Although in vitro cell killing was higher for Ad-WT, XVir-N-31 induced a much stronger immunogenic cell death that was further elevated by blocking PD-1 or PD-L1. In vivo, an intratumoral injection of XVir-N-31 increased tumor infiltrating lymphocytes (TILs) and NK cells significantly more than Ad-WT not only in the virus-injected tumors, but also in the untreated tumors growing in the contralateral hemisphere. This suggests that for an effective treatment of GBM, immune activating properties by OAVs seem to be of greater importance than their oncolytic capacity. Furthermore, the addition of immune checkpoint inhibition (ICI) to OVT further induced lymphocyte infiltration. Consequently, a significant reduction in contralateral non-virus-injected tumors was only visible if OVT was combined with ICI. This strongly indicates that for an effective eradication of GBM cells that cannot be directly targeted by an intratumoral OV injection, additional ICI therapy is required.  相似文献   
54.
55.
56.
57.
Repair of Cracks in Reinforced Concrete Structures after Accidental Action Accidental loads – for example an earthquake, a vehicle impact or blast and shock waves due to detonations – lead to local damages in RC‐structures. Both the damage assessment as well as the repair of damaged reinforced concrete are important topics with respect to a durable use of infrastructure. After damage assessment a further step focuses on the repair of damaged structural concrete. Therefore fundamental investigations concerning the use of different repair methodologies have been carried out with respect to damage after accidental action. The grouting techniques used focus on the repair of cracks, the concretes microstructure and the weakened bond between reinforcement bars and concrete in the surrounding damage zone. Furthermore this contribution includes applicationoriented experimental investigations concerning the repair of reinforced concrete components by grouting and a discussion of the appropriateness for repairing RC‐structures damaged by accidental action.  相似文献   
58.
In this paper, we present an aero‐structural model of a tethered swept wing for airborne wind energy generation. The carbon composite wing has neither fuselage nor actuated aerodynamic control surfaces and is controlled entirely from the ground using three separate tethers. The computational model is efficient enough to be used for weight optimisation at the initial design stage. The main load‐bearing wing component is a nontypical “D”‐shaped wing‐box, which is represented as a slender carbon composite shell and further idealised as a stack of two‐dimensional cross section models arranged along an anisotropic one‐dimensional beam model. This reduced 2+1D finite element model is then combined with a nonlinear vortex step method that determines the aerodynamic load. A bridle model is utilised to calculate the individual forces as a function of the aerodynamic load in the bridle lines that connect the main tether to the wing. The entire computational model is used to explore the influence of the bride on the D‐box structure. Considering a reference D‐box design along with a reference aerodynamic load case, the structural response is analysed for typical bridle configurations. Subsequently, an optimisation of the internal geometry and laminate fibre orientations is carried out using the structural computation models, for a fixed aerodynamic and bridle configuration. Aiming at a minimal weight of the wing structure, we find that for the typical load case of the system, an overall weight savings of approximately 20% can be achieved compared with the initial reference design.  相似文献   
59.
Platinum diselenide (PtSe2) is a 2D material with outstanding electronic and piezoresistive properties. The material can be grown at low temperatures in a scalable manner, which makes it extremely appealing for many potential electronics, photonics, and sensing applications. Here, the nanocrystalline structure of different PtSe2 thin films grown by thermally assisted conversion (TAC) is investigated and is correlated with their electronic and piezoresistive properties. Scanning transmission electron microscopy for structural analysis, X-ray photoelectron spectroscopy (XPS) for chemical analysis, and Raman spectroscopy for phase identification are used. Electronic devices are fabricated using transferred PtSe2 films for electrical characterization and piezoresistive gauge factor measurements. The variations of crystallite size and their orientations are found to have a strong correlation with the electronic and piezoresistive properties of the films, especially the sheet resistivity and the effective charge carrier mobility. The findings may pave the way for tuning and optimizing the properties of TAC-grown PtSe2 toward numerous applications.  相似文献   
60.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号