全文获取类型
收费全文 | 258篇 |
免费 | 5篇 |
国内免费 | 3篇 |
专业分类
化学 | 135篇 |
晶体学 | 1篇 |
力学 | 7篇 |
数学 | 76篇 |
物理学 | 47篇 |
出版年
2023年 | 2篇 |
2022年 | 6篇 |
2021年 | 6篇 |
2020年 | 12篇 |
2019年 | 16篇 |
2018年 | 14篇 |
2017年 | 9篇 |
2016年 | 13篇 |
2015年 | 11篇 |
2014年 | 17篇 |
2013年 | 43篇 |
2012年 | 23篇 |
2011年 | 21篇 |
2010年 | 10篇 |
2009年 | 18篇 |
2008年 | 5篇 |
2007年 | 11篇 |
2006年 | 5篇 |
2005年 | 4篇 |
2004年 | 3篇 |
2003年 | 1篇 |
2002年 | 1篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1980年 | 1篇 |
排序方式: 共有266条查询结果,搜索用时 390 毫秒
211.
212.
Ali Rezaei Saeme Asgari Samira Komijani Seyedeh Narjes Sadat Jean-Marc Sabatier Davood Nasrabadi Kamran Pooshang Bagheri Delavar Shahbazzadeh Mohammad Reza Akbari Eidgahi Michel De Waard Hasan Mirzahoseini 《Molecules (Basel, Switzerland)》2022,27(7)
Cancer is one of the leading causes of mortality in the world. Unfortunately, the present anticancer chemotherapeutics display high cytotoxicity. Accordingly, the discovery of new anticancer agents with lower side effects is highly necessitated. This study aimed to discover an anticancer compound from Hemiscorpius lepturus scorpion venom. Bioactivity-guided chromatography was performed to isolate an active compound against colon and breast cancer cell lines. 2D electrophoresis and MALDI-TOF were performed to identify the molecule. A partial protein sequence was obtained by mass spectrometry, while the full-length was deciphered using a cDNA library of the venom gland by bioinformatics analyses and was designated as leptulipin. The gene was cloned in pET-26b, expressed, and purified. The anticancer effect and mechanism action of leptulipin were evaluated by MTT, apoptosis, and cell cycle assays, as well as by gene expression analysis of apoptosis-related genes. The treated cells displayed inhibition of cell proliferation, altered morphology, DNA fragmentation, and cell cycle arrest. Furthermore, the treated cells showed a decrease in BCL-2 expression and an increase in Bax and Caspase 9 genes. In this study, we discovered a new anticancer protein from H. lepturus scorpion venom. Leptulipin showed significant anticancer activity against breast and colon cancer cell lines. 相似文献
213.
The use of a non-steady ejector based on wave rotor technology is modeled for pulse detonation engine performance improvement
and for compatibility with turbomachinery components in hybrid propulsion systems. The rotary wave ejector device integrates
a pulse detonation process with an efficient momentum transfer process in specially shaped channels of a single wave-rotor
component. In this paper, a quasi-one-dimensional numerical model is developed to help design the basic geometry and operating
parameters of the device. The unsteady combustion and flow processes are simulated and compared with a baseline PDE without
ejector enhancement. A preliminary performance assessment is presented for the wave ejector configuration, considering the
effect of key geometric parameters, which are selected for high specific impulse. It is shown that the rotary wave ejector
concept has significant potential for thrust augmentation relative to a basic pulse detonation engine. 相似文献
214.
Poly(ethylene glycol) dicationic ionic liquid‐based MnCl42? was prepared by nucleophilic substitution of poly(ethylene glycol) dichloride with methylimidazole followed by reaction with MnCl2. The structural properties of the catalyst were systematically investigated using Fourier transform infrared, UV–visible and Raman spectra and thermogravimetric analysis. The application of this catalyst allows the synthesis of a variety of benzyl thiocyanates and azides in high yield under reflux conditions in water. The main advantages of this method are its easy nature, rapidity, environmental benignity and high yields. 相似文献
215.
Khodabandeh Erfan Akbari Omid Ali Akbari Soheil Taghizadeh Afshin Saffari Pour Mohsen Ersson Mikael Jönsson Pär G. 《Journal of Thermal Analysis and Calorimetry》2021,144(1):245-256
Journal of Thermal Analysis and Calorimetry - In this numerical study, the variations in the surface area of the cooling channels in a solid oxide fuel cell with different cross sections... 相似文献
216.
217.
Akbari Vakilabadi M. Bidi M. Najafi A. F. Ahmadi Mohammad Hossein 《Journal of Thermal Analysis and Calorimetry》2020,139(2):1275-1290
Journal of Thermal Analysis and Calorimetry - Water scarcity and environmental impacts of blowdown within steam power plants are among the important growing concerns. In order to solve these... 相似文献
218.
219.
The left multiplicative continuous compactification is the universal semigroup compactification of a semitopological semigroup. In this paper an internal construction of a quotient space of the left multiplicative continuous compactification of a semitopological semigroup is constructed as a space of z-filters. 相似文献
220.
Doppler cooling of 88Sr atoms is studied in the presence of off-resonant red-detuned fluctuating laser fields.Using a semi-classical approach,we show that the relevant physical quantities in the cooling process,such as optical forces,the damping coefficient,Doppler temperature,and atom number in the trap,are strongly affected by the laser amplitude and phase fluctuations.We find that the Doppler cooling limit is higher than the predicted Doppler theory for non-fluctuating lasers.This ... 相似文献