全文获取类型
收费全文 | 255篇 |
免费 | 11篇 |
专业分类
化学 | 195篇 |
晶体学 | 3篇 |
力学 | 7篇 |
数学 | 23篇 |
物理学 | 38篇 |
出版年
2023年 | 2篇 |
2022年 | 4篇 |
2021年 | 9篇 |
2020年 | 10篇 |
2019年 | 9篇 |
2018年 | 8篇 |
2017年 | 10篇 |
2016年 | 6篇 |
2015年 | 5篇 |
2014年 | 16篇 |
2013年 | 22篇 |
2012年 | 33篇 |
2011年 | 29篇 |
2010年 | 15篇 |
2009年 | 23篇 |
2008年 | 18篇 |
2007年 | 7篇 |
2006年 | 7篇 |
2005年 | 2篇 |
2004年 | 4篇 |
2003年 | 5篇 |
2002年 | 5篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1988年 | 1篇 |
1987年 | 2篇 |
排序方式: 共有266条查询结果,搜索用时 15 毫秒
1.
Mat Rasol Awang Hassan Hamdani Mutaat Mohd. Shukri Mahmud Wan Badrin Wan Husain Tajuddin Osman Khomsaton Abu Bakar Asmahwati Kassim Zal U''yun Wan Mahmud Ishak ManafTamikazu Kume Shoji Hashimoto 《Radiation Physics and Chemistry》1993,42(4-6):611-616
In solid state fermentation, Pleurotus sajor-caju has been found to be able to degrade at least 30% oil palm empty Fruit Bunch (EFB) fibre leaving 70 % useful materials. Conditions under which fermentation carried out were investigated. It was found that, in the temperature range between 25– 28 °C, relative ph between 6–8, moisture between 60–70 % and medium composition of CaCO3: rice bran 2 %: 5 % were the optimum conditions. The results showed in fermented products that, there were substantial reduction in cellulosic component such as Crude Fiber (CF, 18 %); Acid Detergent Fibre (ADF, 45 %), Neutral Detergent Fibre (NDF, 61 %) and Acid Detergent Lignin (ADL, 14 %). However, Crude Protein (CP, 10%) increased resulted from single cell protein enrichment of mycelial microbial mass. The mass reductions of substrate in fermentation process corresponds to the CO2 released during fermentation. Hence, attributable to the decreased in content of CF, ADF, NDF, and ADL. The digestibility study has also been carried out to determine the useful level of this product to ruminant. Aflatoxin content was detected low in both the initial substrates and products. Based on nutritional value and low content of aflatoxin, the product is useful as a source of roughage to ruminant. 相似文献
2.
Norimah Yusof A.H. Ainul Hafiza Rozaini M. Zohdi Md Zuki A. Bakar 《Radiation Physics and Chemistry》2007,76(11-12):1767-1770
Radiation at 25 and 50 kGy showed no effect on the acidic pH of the local honey, Gelam, and its antimicrobial property against Staphylococcus aureus but significantly reduced the viscosity. Honey stored up to 2 years at room temperature retained all the properties studied. Radiation sterilized Gelam honey significantly stimulated the rate of burn wound healing in Sprague-Dawley rats as demonstrated by the increased rate of wound contraction and gross appearance. Gelam honey attenuates wound inflammation; and re-epithelialization was well advanced compared to the treatment using silver sulphadiazine (SSD) cream. To enhance further the use of honey in wound treatment and for easy handling, Gelam honey was incorporated into our hydrogel dressing formulation, which was then cross-linked and sterilized using electron beam at 25 kGy. Hydrogel with 6% of honey was selected based on the physical appearance. 相似文献
3.
Atta-ur-Rahman Nasim S Baig I Sener B Orhan I Ayanoglu F Choudhary MI 《Natural product research》2004,18(5):465-471
Two new isoflavones 1 and 2 along with eleven known compounds 3-13, have been isolated for the first time from the rhizomes of Iris soforana. The structures of these compounds were determined on the basis of spectroscopic methods and found to be 5,3'-dihydroxy-4'-methoxy-6,7-methylenedioxyisoflavone (1) (Soforanarin A), and 5,7,5'-trimethoxy-6,3',4'-trihydroxyisoflavone (2) (Soforanarin B). 相似文献
4.
Leyla Bitiş Sevda Süzgeç Ulaş Sözer Hasan Özçelik Josef Zapp Alexandra K. Kiemer Filiz Meriçli Ali H. Meriçli 《Helvetica chimica acta》2007,90(11):2217-2221
From the aerial parts of Delphinium buschianum Grossh ., collected in Turkey, a new diterpenoid alkaloid 1 , named budelphine, was isolated along with the known diterpenoid alkaloids karakoline ( 2 ), 18‐hydroxy‐14‐O‐methylgadesine ( 3 ), delsoline ( 4 ), lapaconidine ( 5 ), columbianine ( 6 ), 14‐benzoylneoline ( 7 ), and hetisine ( 9 ). The structure of 1 was established on the basis of 1H‐, 13C‐, DEPT, 1H,1H‐COSY, NOESY, HSQC, and HMBC NMR studies. 相似文献
5.
6.
Joseph T. Hill-Cousins Sofia S. Salim Youssef M. Bakar Richard K. Bellingham Mark E. Light Richard C.D. Brown 《Tetrahedron》2014
Ring-closing metathesis (RCM) and sequential Yb(OTf)3 promoted Diels–Alder reactions of sulfamide-linked enynes proceeded selectively in one-pot to afford a series of bicyclic and tricyclic sulfamides. Excellent levels of diastereoselectivity are observed for the cycloaddition step, with only the endo-adducts being isolated. The protocol was further extended to incorporate a one-pot RCM–cross metathesis (CM)–Diels–Alder sequence, permitting rapid access to high levels of molecular complexity from simple and easily accessible precursors. 相似文献
7.
Saadi Bayat Emilia Abd Malek Normi M. Yahaya Abu Bakar Salleh Bimo Ario Tejo Mohd Basyaruddin Abdul Rahman 《Tetrahedron letters》2014
The promiscuous aldo–ketoreductase (AKR) enzyme is used as a sustainable biocatalyst for the first time to catalyze asymmetric aldol reactions in aqueous medium. The reactions between aromatic aldehydes and cyclic/acyclic ketones give the corresponding products in moderate yields and enantioselectivities in the presence of water. The influence of solvents, the mole ratio of substrates, and enzyme concentration are investigated. The mechanism of the AKR1A1-catalyzed aldol reaction is also discussed. 相似文献
8.
9.
G. Al-mahbashi M.S. Md Noorani S.A. Bakar M.M. Al-sawalha 《The European physical journal. Special topics》2016,225(1):51-64
This paper investigates the problem of projective lag synchronization behavior in drive-response dynamical networks (DRDNs) with identical and non-identical nodes. An adaptive control method is designed to achieve projective lag synchronization with fully unknown parameters and unknown bounded disturbances. These parameters were estimated by adaptive laws obtained by Lyapunov stability theory. Furthermore, sufficient conditions for synchronization are derived analytically using the Lyapunov stability theory and adaptive control. In addition, the unknown bounded disturbances are also overcome by the proposed control. Finally, analytical results show that the states of the dynamical network with non-delayed coupling can be asymptotically synchronized onto a desired scaling factor under the designed controller. Simulation results show the effectiveness of the proposed method. 相似文献
10.
M. N. Hafiza A. N. A. Bashirah N. Y. Bakar 《International Journal of Polymer Analysis and Characterization》2014,19(2):151-158
This present work discusses dual-blend green polymer electrolyte (GPE)–based natural polymers, composed of carboxyl methylcellulose (CMC) and chitosan (CS), created by introducing various compositions of ammonium bromide (NH4Br) as a dopant in the system. These GPEs were successfully prepared by the solution casting technique and characterized using electrical impedance spectroscopy (EIS). From EIS measurement, the highest room-temperature conductivity is 1.21 × 10?5 Scm?1 for the sample containing 20 wt.% of NH4Br. Plot of the temperature dependence of the GPEs revealed that the system obeys the Arrhenius rule and was thermally assisted. Besides that, dielectric studies were also conducted and the data were analyzed using complex permittivity, ?*, and complex electrical modulus, M*, to determine the sample with the highest conductivity value. Thus, this study confirmed non-Debye behavior in the sample. 相似文献