全文获取类型
收费全文 | 583篇 |
免费 | 10篇 |
国内免费 | 2篇 |
专业分类
化学 | 422篇 |
晶体学 | 31篇 |
力学 | 13篇 |
数学 | 64篇 |
物理学 | 65篇 |
出版年
2024年 | 1篇 |
2023年 | 7篇 |
2022年 | 10篇 |
2021年 | 16篇 |
2020年 | 16篇 |
2019年 | 21篇 |
2018年 | 19篇 |
2017年 | 17篇 |
2016年 | 17篇 |
2015年 | 20篇 |
2014年 | 11篇 |
2013年 | 42篇 |
2012年 | 30篇 |
2011年 | 44篇 |
2010年 | 48篇 |
2009年 | 33篇 |
2008年 | 51篇 |
2007年 | 37篇 |
2006年 | 30篇 |
2005年 | 35篇 |
2004年 | 26篇 |
2003年 | 20篇 |
2002年 | 14篇 |
2001年 | 4篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1997年 | 6篇 |
1995年 | 4篇 |
1994年 | 1篇 |
1991年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1978年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有595条查询结果,搜索用时 125 毫秒
591.
Çiğdem Albayrak Başak Koşar Mustafa Odabaşoğlu Orhan Büyükgüngör 《Crystallography Reports》2010,55(7):1203-1206
The crystal structure of hexakis(4-phormylphenoxy)cyclotriphosphazene is determined by using X-ray diffraction and then the
molecular structure is investigated with density functional theory (DFT). X-Ray study shows that the title compound has C-H…π
interaction with phosphazene ring. The molecules in the unit cell are packed with Van der Waals and dipole-dipole interactions
and the molecules are packed in zigzag shaped. Optimized molecular geometry is calculated with DFT at B3LYP/6-311G(d,p) level.
The results from both experimental and theoretical calculations are compared in this study. 相似文献
592.
The present study aimed to characterize the physical properties of nanoemulsion-based sodium alginate edible coatings containing myrtle (Myrtus communis L.) essential oil and to determine its inhibitory effects on Listeria monocytogenes in fresh Kasar cheese during the 24-day storage at 4 °C. The GC-MS analysis showed that the main components of myrtle essential oil were 1,8-cineol (38.64%), α-pinene (30.19%), d-limonene (7.51%), and α-ocimene (6.57%). Myrtle essential oil showed an inhibitory effect on all tested L. monocytogenes strains and this effect significantly increased after ultrasonication. Minimum inhibitory and minimum bactericidal concentrations of myrtle essential oil nanoemulsion were found to be 4.00–4.67 mg/mL and 5.00–7.33 mg/mL, respectively. The antibacterial activity of myrtle essential oil nanoemulsion against L. monocytogenes was confirmed by the membrane integrity and FESEM analyses. Nanoemulsion coatings containing myrtle essential oil showed antibacterial activity against L. monocytogenes with no adverse effects on the physicochemical properties of cheese samples. Nanoemulsion coatings containing 1.0% and 2.0% myrtle essential oil reduced the L. monocytogenes population in cheese during the storage by 0.42 and 0.88 log cfu/g, respectively. These results revealed that nanoemulsion-based alginate edible coatings containing myrtle essential oil have the potential to be used as a natural food preservative. 相似文献
593.
Elif Burcu Aydın Muhammet Aydın Mustafa Kemal Sezgintürk 《Macromolecular bioscience》2023,23(1):2200390
An early on time detection of breast cancer significantly affects the treatment process and outcome. Herein, a new label-free impedimetric biosensor is developed to determine the lowest change in the level of calreticulin (CALR), which is a new biomarker of breast carcinoma. The proposed immunosensor is fabricated by using reduced graphene oxide/amino substituted polypyrrole polymer (rGO-PPyNH2) nanocomposite modified disposable electrode. The anti-CALR antibodies are first attached on the rGO-PPyNH2 nanocomposite coated electrode through glutaraldehyde crosslinking; the CALR antigens are then immobilized with the addition of CALR antigens to form an immunocomplex on the sensing surface. This immunocomplex induces considerably larger interfacial electron transport resistance (Rct). The variation in the Rct has a linear relationship with CALR level in the detection range of 0.025 to 75 pg mL−1, with a detection limit of 10.4 fg mL−1. The suggested biosensor shows high selectivity to CALR, good storage stability (at least 5 weeks) and suitable reproducibility results as shown in quality control chart. The designed immunosensor is utilized to analyze CALR levels in human sera with satisfying results. This immunosensor provides a novel way for the clinical determination of CALR and other cancer biological markers. 相似文献
594.
Two different classes of drugs were selected to test the adsorption capacity of carbon nanofibers as a greener new generation alternative adsorbent in simulated gastric and intestinal fluids. Kinetics of the promethazine and trimethoprim adsorption were analyzed using Lagergren first order and Pseudo second order models. Intraparticle diffusion graphs were also plotted to discuss the adsorption mechanism. Kinetic data showed the significance of boundary layer effect for both of the drugs and the presence of intraparticle diffusion as the other rate controlling step for the promethazine adsorption. Giles isotherms showed the high affinity of drug molecules to the adsorbent. Maximum adsorption capacity of drugs was calculated using Langmuir model as 18.35 and 41.15 mg/g for trimethoprim and 95.24 and 80.65 mg/g for promethazine in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF), respectively. Trimethoprim adsorption was under favor of hydrophobic interaction and π-π dispersion interactions while promethazine adsorption was through cation exchange where the electrostatic attraction is an important force with the contribution of dispersion interactions. 相似文献
595.
Central European Journal of Operations Research - We consider the model of a transportation problem with the objective of finding a minimum-cost transportation plan for shipping a given... 相似文献