全文获取类型
收费全文 | 139篇 |
免费 | 5篇 |
专业分类
化学 | 48篇 |
晶体学 | 2篇 |
力学 | 17篇 |
数学 | 13篇 |
物理学 | 64篇 |
出版年
2023年 | 1篇 |
2022年 | 4篇 |
2021年 | 5篇 |
2020年 | 3篇 |
2019年 | 3篇 |
2018年 | 5篇 |
2017年 | 7篇 |
2016年 | 9篇 |
2015年 | 8篇 |
2014年 | 7篇 |
2013年 | 8篇 |
2012年 | 12篇 |
2011年 | 14篇 |
2010年 | 2篇 |
2009年 | 4篇 |
2008年 | 10篇 |
2007年 | 9篇 |
2006年 | 1篇 |
2005年 | 2篇 |
2004年 | 3篇 |
2003年 | 2篇 |
2002年 | 4篇 |
2001年 | 1篇 |
2000年 | 6篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1986年 | 1篇 |
1983年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有144条查询结果,搜索用时 31 毫秒
111.
112.
M. Manuela M. Raposo Ana M. B. A. Sampaio G. Kirsch 《Journal of heterocyclic chemistry》2005,42(7):1245-1251
A synthesis of 1‐alkoxy‐ and 1‐amino‐ substituted 4‐(2‐thienyl)‐phthalazines is described from halo‐derivatives of 4‐(2‐thienyl)‐l‐(2H)‐phthalazinone 3. 相似文献
113.
114.
The Picrosirius-polarization method has been indicated as a selective histochemical stain for collagen detection in tissue sections. This method can also be of value for studying collagen degradation given that, under polarized light, collagen displays birefringence due to its molecular order. The aim of this study is to highlight this staining method as an additional instrument for a rapid and excellent confirmatory diagnosis of the presence of collagenolysis in connective tissue in the vaginal wall with vesical prolapse lesion, in tissue sections. Dramatic changes in collagen morphology were found in vaginal mucosa in vesical prolapse disorder: they were weakly stained by Sirius red and under polarized light appeared as thin, pale (weakly birefringent), greenish, and with fibers more scattered, while the histoarchitecture of the organ showed a disrupted appearance. Thus, in the present study, we showed in vaginal mucosa in the vesicle prolapse that corroded collagenous framework appears as fragmentary and irregularly separated collagenous structures, that are weakly birefringent, corresponding to a molecular disorganization of these fibers caused by collagenolysis. 相似文献
115.
Influence of inhibitory compounds and minor sugars on xylitol production by Debaryomyces hansenii 总被引:1,自引:0,他引:1
Sampaio FC Torre P Passos FM de Moraes CA Perego P Converti A 《Applied biochemistry and biotechnology》2007,136(2):165-182
To obtain in-depth information on the overall metabolic behavior of the new good xylitol producer Debaryomyces hansenii UFV-170, batch bioconversions were carried out using semisynthetic media with compositions simulating those of typical acidic hemicellulose hydrolysates of sugarcane bagasse. For this purpose, we used media containing glucose (4.3-6.5 g/L), xylose (60.1-92.1 g/L), or arabinose (5.9-9.2 g/L), or binary or ternary mixtures of them in either the presence or absence of typical inhibitors of acidic hydrolysates, such as furfural (1.0-5.0 g/L), hydroxymethylfurfural (0.01- 0.30 g/L), acetic acid (0.5-3.0 g/L), and vanillin (0.5-3.0 g/L). D. hansenii exhibited a good tolerance to high sugar concentrations as well as to the presence of inhibiting compounds in the fermentation media. It was able to produce xylitol only from xylose, arabitol from arabinose, and no glucitol from glucose. Arabinose metabolization was incomplete, while ethanol was mainly produced from glucose and, to a lesser less extent, from xylose and arabinose. The results suggest potential application of this strain in xyloseto- xylitol bioconversion from complex xylose media from lignocellulosic materials. 相似文献
116.
Purification of a PHA-Like Chitin-binding Protein from Acacia farnesiana Seeds: A Time-dependent Oligomerization Protein 总被引:1,自引:0,他引:1
Santi-Gadelha T Rocha BA Oliveira CC Aragão KS Marinho ES Gadelha CA Toyama MH Pinto VP Nagano CS Delatorre P Martins JL Galvani FR Sampaio AH Debray H Cavada BS 《Applied biochemistry and biotechnology》2008,150(1):97-111
A lectin-like protein from the seeds of Acacia farnesiana was isolated from the albumin fraction, characterized, and sequenced by tandem mass spectrometry. The albumin fraction was extracted with 0.5 M NaCl, and the lectin-like protein of A. farnesiana (AFAL) was purified by ion-exchange chromatography (Mono-Q) followed by chromatofocusing. AFAL agglutinated rabbit erythrocytes and did not agglutinate human ABO erythrocytes either native or treated with proteolytic enzymes. In sodium dodecyl sulfate gel electrophoresis under reducing and nonreducing conditions, AFAL separated into two bands with a subunit molecular mass of 35 and 50 kDa. The homogeneity of purified protein was confirmed by chromatofocusing with a pI = 4.0 +/- 0.5. Molecular exclusion chromatography confirmed time-dependent oligomerization in AFAL, in accordance with mass spectrometry analysis, which confers an alteration in AFAL affinity for chitin. The protein sequence was obtained by a liquid chromatography quadrupole time-of-flight experiment and showed that AFAL has 68% and 63% sequence similarity with lectins of Phaseolus vulgaris and Dolichos biflorus, respectively. 相似文献
117.
118.
Based on high-order linear multistep methods (LMMs), we use the class
of extended trapezoidal rules (ETRs) to solve boundary value problems of ordinary
differential equations (ODEs), whose numerical solutions can be approximated by
boundary value methods (BVMs). Then we combine this technique with fourth-order
Padé compact approximation to discrete 2D Schrödinger equation. We propose a
scheme with sixth-order accuracy in time and fourth-order accuracy in space. It is
unconditionally stable due to the favourable property of BVMs and ETRs. Furthermore,
with Richardson extrapolation, we can increase the scheme to order 6 accuracy
both in time and space. Numerical results are presented to illustrate the accuracy of
our scheme. 相似文献
119.
120.