全文获取类型
收费全文 | 92篇 |
免费 | 1篇 |
专业分类
化学 | 17篇 |
数学 | 25篇 |
物理学 | 51篇 |
出版年
2021年 | 1篇 |
2014年 | 1篇 |
2012年 | 1篇 |
2011年 | 3篇 |
2010年 | 2篇 |
2008年 | 3篇 |
2007年 | 3篇 |
2006年 | 3篇 |
2005年 | 1篇 |
2003年 | 4篇 |
2002年 | 2篇 |
2001年 | 4篇 |
2000年 | 1篇 |
1999年 | 4篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1992年 | 6篇 |
1991年 | 1篇 |
1990年 | 4篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1976年 | 2篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1962年 | 1篇 |
1960年 | 1篇 |
1957年 | 1篇 |
1955年 | 1篇 |
1946年 | 1篇 |
1945年 | 1篇 |
1943年 | 1篇 |
1941年 | 1篇 |
1928年 | 1篇 |
1919年 | 1篇 |
1916年 | 2篇 |
1915年 | 1篇 |
1914年 | 2篇 |
1913年 | 1篇 |
1912年 | 1篇 |
1910年 | 1篇 |
1894年 | 1篇 |
1889年 | 1篇 |
排序方式: 共有93条查询结果,搜索用时 406 毫秒
1.
2.
Abbotto A Beverina L Bozio R Facchetti A Ferrante C Pagani GA Pedron D Signorini R 《Organic letters》2002,4(9):1495-1498
[structure: see text]. The synthesis and nonlinear optical characterization of two novel heteroaromatic-based chromophores is described. The new dyes present an A-pi-D-pi-A general framework, where A is a pi-deficient heteroaromatic ring (pyridine, quinoline, benzothiazole) and D a pi-excessive pyrrolyl moiety. Both systems exhibit large two-photon absorption (TPA) values in the femtoseconds regime (TPA cross section as high as 150 x 10(-50) cm(4) s photon(-1) molecule(-1) with 150 fs laser pulses). Their TPA-based optical limiting activity is also shown. 相似文献
3.
Abbotto A Beverina L Bozio R Facchetti A Ferrante C Pagani GA Pedron D Signorini R 《Chemical communications (Cambridge, England)》2003,(17):2144-2145
The first examples of heterocycle-based multi-branched dyes with efficient two-photon absorption (TPA) activity are reported; the novel chromophores exhibit large TPA cross sections (as high as 1600 x 10(-50) cm4 s photon(-1) molecule(-1), measured with 150 fs laser pulses at 800 nm); a strong cooperative enhancement in the branched systems with respect to the one-dimensional sub-units is found. 相似文献
4.
Gioria Esteban Signorini Chiara Taleb María C. Thomas Arne Mihályi Magdolna R. Gutierrez Laura 《Cellulose (London, England)》2021,28(14):9135-9147
Cellulose - Palladium was incorporated into carboxymethylated cellulose fibers as a support, thereby becoming an efficient and stable catalyst for low temperature gas phase reaction. Thus, NO was... 相似文献
5.
A lot of methods were created in last decade for the spatio-temporal analysis of multi-electrode array (MEA) neuronal data
sets. In this paper we show how a new simple analysis approach that considers the total network activity, is able to show
interesting neuronal network system dynamical features. In particular, we perform two different analyses: a neuronal connectivity
examination studying networks at different days in vitro (div) and an analysis of the long per- iod effects of the administration of two common neuroactive drugs, Tetrodotoxin (TTX)
and D-2-amino-5-phosphonovalerate (AP5), to spontaneously spiking mature neuronal networks. Our analysis is performed considering
burst topology, i.e., cataloguing network bursts as Global (if they involve more than the 25% of the MEA channels) or Local
(if less that 25%). In the first analysis, this division allows to understand the network connectivity developments. The networking
increases from div 1 to 6 building up an undifferentiated highly connected network. From div 6 to 10 the networking decreases
(pruning) till reaching a plateau in a small-world like organization. The second analysis highlights substantial differences
between long period effects of TTX and AP5. Results show that AP5, selectively blocking NMDA receptors and inhibiting long
term potentiation, is unable to produce activity twisting in a network that already reached a developmental plateau, but it
is able to desynchronize sub-network (Local) activity. TTX, on the other side, blocking any type of electrical communication
among neurons, acts on the whole network synchronization. The important activity increment in the post-TTX epoch (+66%), together
with the Global activity explosion, suggests the possibility of a long-term inhibitory-synapse depression mechanism. 相似文献
6.
T. Faestermann F. Feilitzsch R. S. Raghavan C. Signorini T. Yamazaki C. V. K. Baba D. B. Fossan D. Proetel 《Zeitschrift für Physik A Hadrons and Nuclei》1975,275(2):157-161
Then th,α)-reaction spectroscopical data are reported on95Mo,123Te and145Nd (target nuclei). The95Mo(n, α)92Zr and123Te(n, α)120Sn reactions showed up two lines each corresponding to the ground state and the 1st excited state with a total cross section of 32 ub and 52 μb respectively. In the case of145Nd(n, α)142Ce, a transition only to the 1st excited state of142Ce is present. It is shown that in the case of95Mo,145Nd and probably123Te, most of the cross-section comes respectively from the 2+ possibly 4?, and 0 bound levels whose widths are determined to beΓ α=0.5 × 10?6 eV,Γ α=1.6×10?8 eV andΓ α=1.6 × 10?6 eV. The present results on these three nuclei, when combined with the existing data, are consistent with the calculated statistical model values. 相似文献
7.
A. Signorini 《Annali di Matematica Pura ed Applicata》1943,22(1):33-143
Sunto. Con questa Memoria l'A. inizia l'esposizione sistematica delle sue ricerche nell'ambito della Elasticità non linearizzata,
per dare completo sviluppo a quanto molto sinteticamente si trova accennato in tre conferenze tenute a Stoccolma [3.o Congr. int. di Mecc. appl., 1930], a Palermo [XXIV Riunione della S.I.P.S., 1935], a Bologna [2.o Congr. della U.M.I., 1940] e nella relazione da lui svolta nel recente convegno internazionale di matematici a Roma. 相似文献
8.
9.
P. J. Daly S. Lunardi F. Soramel M. Morando C. Signorini B. Fornal G. Fortuna A. M. Stefanini W. Meczynski 《Zeitschrift für Physik A Hadrons and Nuclei》1986,325(2):245-246
A simple evaporation and percolation model is applied to calculate the amount of excitation energy needed to have multifragmentation. 相似文献
10.