全文获取类型
收费全文 | 132篇 |
免费 | 0篇 |
专业分类
化学 | 60篇 |
晶体学 | 1篇 |
数学 | 13篇 |
物理学 | 58篇 |
出版年
2022年 | 5篇 |
2021年 | 3篇 |
2020年 | 1篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2013年 | 6篇 |
2012年 | 6篇 |
2011年 | 11篇 |
2010年 | 6篇 |
2009年 | 1篇 |
2008年 | 9篇 |
2007年 | 3篇 |
2006年 | 2篇 |
2005年 | 3篇 |
2003年 | 4篇 |
2002年 | 1篇 |
2001年 | 2篇 |
2000年 | 8篇 |
1999年 | 5篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 4篇 |
1995年 | 7篇 |
1994年 | 7篇 |
1993年 | 5篇 |
1992年 | 6篇 |
1991年 | 3篇 |
1990年 | 4篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1974年 | 1篇 |
1930年 | 2篇 |
排序方式: 共有132条查询结果,搜索用时 15 毫秒
11.
Emission spectra of the b1Sigma+(b0(+)) --> X3Sigma-(X10(+), X21) and a1Delta(a2) --> X21 transitions of AsI have been measured in the near-infrared spectral region with a Fourier-transform spectrometer. The arsenic iodide radicals were generated and excited in a fast-flow system by reaction of arsenic vapor (Asx) with iodine and microwave-discharged oxygen. The most prominent features in the spectrum are six band sequences of the strong b1Sigma+(b0(+)) --> X3Sigma-(X10(+)) transition in the range 800-900 nm. With much lower intensities the hitherto unknown b1Sigma+(b0(+)) --> X3Sigma-(X21) subsystem and the a1Delta(a2) --> X21 transition near 1660 nm are observed. Vibrational analyses have yielded improved molecular constants for the X10(+) and b0(+) states and first values of the electronic energies and vibrational constants of the X21 and a2 states (in cm-1), X21: Te = 289.8(2), omegae = 255.2(2), omegaexe = 0.68(7), a2: Te = 6305.4(3), omegae = 267.8(1), omegaexe = 0.56(2), where the numbers in parentheses are the standard deviations of the parameters. Copyright 1999 Academic Press. 相似文献
12.
Wm. Lerch R. H. Bogue E. S. Shepherd G. A. Rankin F. E. Wright F. Ferrari J. Stanton Pierce W. C. Setzer F. Strumpf und R. H. H. Stanger 《Fresenius' Journal of Analytical Chemistry》1930,81(12):476-480
Ohne Zusammenfassung 相似文献
13.
14.
Anton Setzer 《Archive for Mathematical Logic》2000,39(3):155-181
We define a type theory MLM, which has proof theoretical strength slightly greater then Rathjen's theory KPM. This is achieved
by replacing the universe in Martin-L?f's Type Theory by a new universe V having the property that for every function f, mapping families of sets in V to families of sets in V, there exists a universe inside V closed under f. We show that the proof theoretical strength of MLM is . This is slightly greater than , and shows that V can be considered to be a Mahlo-universe. Together with [Se96a] it follows .
Received: 8 February 1996 相似文献
15.
K.D. Setzer 《Journal of Molecular Spectroscopy》2003,221(1):127-130
Emission spectra of the 0-0 band of the a1Δg→X3Σ−g magnetic dipole transition of S2 have been observed in the near-infrared spectral region near 4400 cm−1. The S2 molecules were generated in a fast-flow system by passing Sx or S2Cl2 vapor in Ar carrier gas through a microwave discharge and were excited by electronic-to-electronic energy transfer from metastable singlet oxygen O2(a1Δg). Medium-resolution spectra of the b1Σ+g→X3Σ−g and a1Δg→X3Σ−g transitions of S2 were measured with a Fourier-transform spectrometer. By comparing the bandshape of the 0-0 band of the a→X system with a computer simulation calculated with literature data of the rotational constants of the X and a states, the origin of the 0-0 band was determined to be ν0=4394.25±0.2 cm−1. 相似文献
16.
The Bangham equation indicates a direct proportionality between the length change of a porous body and a change of surface energy. In our experiments surface energy of hardened cement paste has been modified by desorbing or adsorbing water molecules. The internal pressure created by surface energy could be directly determined with the help of Mössbauer experiments. Based on these results it is possible to determine to what extent shrinkage or swelling is caused by a change of surface energy. Using Griffith's criterion our findings can explain quantitatively the decrease of stength as a function of increasing water content. Results are in good agreement with other methods of studying surface energy such as experiments to determine van der Waals forces. 相似文献
17.
Ioannis Zalachoras Gwendolynn Grootaers Lisa TCM van Weert Yves Aubert Suzanne R de Kreij Nicole A Datson Willeke MC van Roon-Mom Annemieke Aartsma-Rus Onno C Meijer 《BMC neuroscience》2013,14(1):1-12
Background
Antisense oligonucleotide (AON)-mediated exon skipping is a powerful tool to manipulate gene expression. In the present study we investigated the potential of exon skipping by local injection in the central nucleus of the amygdala (CeA) of the mouse brain. As proof of principle we targeted the splicing of steroid receptor coactivator-1 (SRC-1), a protein involved in nuclear receptor function. This nuclear receptor coregulator exists in two splice variants (SRC-1a and SRC-1e) which display differential distribution and opposing activities in the brain, and whose mRNAs differ in a single SRC-1e specific exon.Methods
For proof of principle of feasibility, we used immunofluorescent stainings to study uptake by different cell types, translocation to the nucleus and potential immunostimulatory effects at different time points after a local injection in the CeA of the mouse brain of a control AON targeting human dystrophin with no targets in the murine brain. To evaluate efficacy we designed an AON targeting the SRC-1e-specific exon and with qPCR analysis we measured the expression ratio of the two splice variants.Results
We found that AONs were taken up by corticotropin releasing hormone expressing neurons and other cells in the CeA, and translocated into the cell nucleus. Immune responses after AON injection were comparable to those after sterile saline injection. A successful shift of the naturally occurring SRC-1a:SRC-1e expression ratio in favor of SRC-1a was observed, without changes in total SRC-1 expression.Conclusions
We provide a proof of concept for local neuropharmacological use of exon skipping by manipulating the expression ratio of the two splice variants of SRC-1, which may be used to study nuclear receptor function in specific brain circuits. We established that exon skipping after local injection in the brain is a versatile and useful tool for the manipulation of splice variants for numerous genes that are relevant for brain function. 相似文献18.
KM Varier AM Vinodkumar NVSV Prasad PV Madhusudhana Rao DL Sastry Lagy T Baby MC Radhakrishna NG Puttaswamy JJ Das P Sugathan N Madhavan AK Sinha DO Kataria 《Pramana》1999,53(3):529-533
Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies.
Coupled channel calculations incorporating couplings to 2+ and 3− states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements
had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer
were carried out for 46,48Ti+61Ni systems. The present paper gives the results of these studies. 相似文献
19.
The artificial saturation phenomenon due to freeze–thaw cycles is described by a multi–phase and multiscale model [1,2,3] formulated within the Theory of Porous Media, [4]. It represents partially saturated concrete as a mixture of 5 interacting constituents φα, namely the solid skeleton φs, the bulk water φl, the pore volume occupied by vapour φv, the ice φi and the gel water phase φp. Most relevant for the model is the distinction between two length scales and their characteristic time scales. The boundary is marked where macroscopic bulk conditions change to surface physics and chemistry. Surface physics and chemistry acting on the nano–scale affect fundamental properties of concrete and consequently the durability of concrete against freeze–thaw. At the macroscopic scale the model describes transient conditions (i.e. water–uptake, heat transport, volume dilatation of 9%, phase change of first order considering hysteresis) which are characterized by a relatively long time period to reach equilibrium in contrast to the processes modelled on the microstructure. At the microscopic scale the model represents the nanoscopic CSH–gel system consisting of solid CSH and water as a linked system of both components basing on the concept of the “Solid–Liquid Gel System” [5]. In the constribution the numerical results of the model are presented with focus on the evaluation of the process zone during the penetration of the melting front into the matrix. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
20.
Ali NA Crouch RA Al-Fatimi MA Arnold N Teichert A Setzer WN Wessjohann L 《Natural product communications》2012,7(1):113-116
The chemical composition of the hydrodistilled leaf essential oil from Pulicaria stephanocarpa Balf. Fil was determined by GC-MS analysis, and its antimicrobial, antioxidant and anticholinesterase (AChE) activities were evaluated. Eighty-three compounds were identified representing 97.2% of the total oil. (E)-Caryophyllene 13.4%, (E)-nerolidol 8.5%, caryophyllene oxide 8.5%, alpha-cadinol 8.2% spathulenol 6.8% and tau-cadinol 4.7%, were the main components. Antimicrobial activity of the oil, evaluated using the disc diffusion and broth dilution methods, demonstrated the highest susceptibility on Gram-positive bacteria and Candida albicans. The free radical scavenging ability of the oil was assessed by the DPPH assay to show antiradical activity with IC50 of 330 microg/mL. Moreover, the oil revealed an AChE inhibitory activity of 47% at a concentration of 200 microg/mL using Ellman's method. 相似文献