全文获取类型
收费全文 | 124篇 |
免费 | 4篇 |
国内免费 | 6篇 |
专业分类
化学 | 95篇 |
力学 | 5篇 |
数学 | 6篇 |
物理学 | 28篇 |
出版年
2023年 | 2篇 |
2022年 | 4篇 |
2021年 | 4篇 |
2020年 | 2篇 |
2019年 | 3篇 |
2018年 | 5篇 |
2017年 | 2篇 |
2016年 | 9篇 |
2015年 | 4篇 |
2014年 | 8篇 |
2013年 | 14篇 |
2012年 | 13篇 |
2011年 | 10篇 |
2010年 | 16篇 |
2009年 | 6篇 |
2008年 | 9篇 |
2007年 | 4篇 |
2006年 | 5篇 |
2005年 | 4篇 |
2004年 | 3篇 |
1994年 | 1篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1985年 | 1篇 |
1980年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有134条查询结果,搜索用时 15 毫秒
131.
Peyman Salehi Mahdi Ayyari Morteza Bararjanian Samad Nejad Ebrahimi Atousa Aliahmadi 《Journal of the Iranian Chemical Society》2014,11(3):607-613
A series of novel 2,3-dihydroquinazolin-4(1H)-ones was synthesized by a three-component reaction between dehydroabietylamine (DHA) diterpene, isatoic anhydride and different aromatic aldehydes in the presence of a catalytic amount of p-toluenesulfonic acid (13 mol%). Diastereomeric products were separated by preparative thin-layer chromatography and their structures were characterized by 1H and 13C NMR, HMQC, IR and HR-ESI-MS. Antioxidant activities of the synthesized compounds were assessed by two different methods including DPPH and β-carotene-linoleic acid bleaching assays. Antibacterial activities of the compounds were also evaluated against two Gram-positive and one Gram-negative bacterial strains and in the case of Bacillus cereus a considerable inhibitory effect (MIC 4–16 μg/ml) was observed. 相似文献
132.
Natan Roberto de Barros Mohammad Ali Darabi Xin Ma Sibel Emir Diltemiz Menekse Ermis Alireza Hassani Najafabadi Sara Nadine Ethan A. Banton Kalpana Mandal Reza Abbasgholizadeh Natashya Falcone João F. Mano Rohollah Nasiri Rondinelli Donizetti Herculano Yangzhi Zhu Serge Ostrovidov Junmin Lee Han-Jun Kim Vahid Hosseini Mehmet R. Dokmeci Samad Ahadian Ali Khademhosseini 《Macromolecular bioscience》2023,23(12):2370037
Several microfabrication technologies have been used to engineer native-like skeletal muscle tissues. However, the successful development of muscle remains a significant challenge in the tissue engineering field. Muscle tissue engineering aims to combine muscle precursor cells aligned within a highly organized 3D structure and biological factors crucial to support cell differentiation and maturation into functional myotubes and myofibers. In this study, the use of 3D bioprinting is proposed for the fabrication of muscle tissues using gelatin methacryloyl (GelMA) incorporating sustained insulin-like growth factor-1 (IGF-1)-releasing microparticles and myoblast cells. This study hypothesizes that functional and mature myotubes will be obtained more efficiently using a bioink that can release IGF-1 sustainably for in vitro muscle engineering. Synthesized microfluidic-assisted polymeric microparticles demonstrate successful adsorption of IGF-1 and sustained release of IGF-1 at physiological pH for at least 21 days. Incorporating the IGF-1-releasing microparticles in the GelMA bioink assisted in promoting the alignment of myoblasts and differentiation into myotubes. Furthermore, the myotubes show spontaneous contraction in the muscle constructs bioprinted with IGF-1-releasing bioink. The proposed bioprinting strategy aims to improve the development of new therapies applied to the regeneration and maturation of muscle tissues. 相似文献
133.
Khan MS Kannangara D Shen W Garnier G 《Langmuir : the ACS journal of surfaces and colloids》2008,24(7):3199-3204
The mechanism of the generation and sustainability of noncoalescent droplets (NCDs) was investigated at the liquid-air interface of the same liquids in the context of inkjet printing. The Weber number (We) was used to correlate and predict the generation of NCDs in a falling-drop experiment. This study found that NCDs can be generated for We higher than 130. We values of this magnitude are relevant to inkjet printing. The formation of NCD can reduce the print quality because the NCD droplets roll away uncontrollably from the print target, thus reducing print resolution. This study also used a simple experiment to demonstrate the physical origin of the NCD, which is the existence of a gaseous cushion between the liquid drop and the liquid-air interface that supports the drop. The gaseous cushion has a thickness greater than the van der Waals attraction range (around 10 nm). 相似文献
134.
Gerhard Post Samad Ahmadi Sophia Daskalaki Jeffrey H. Kingston Jari Kyngas Cimmo Nurmi David Ranson 《Annals of Operations Research》2012,194(1):385-397
The High School Timetabling Problem is amongst the most widely used timetabling problems. This problem has varying structures
in different high schools even within the same country or educational system. Due to lack of standard benchmarks and data
formats this problem has been studied less than other timetabling problems in the literature. In this paper we describe the
High School Timetabling Problem in several countries in order to find a common set of constraints and objectives. Our main
goal is to provide exchangeable benchmarks for this problem. To achieve this we propose a standard data format suitable for
different countries and educational systems, defined by an XML schema. The schema and datasets are available online. 相似文献