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排序方式: 共有562条查询结果,搜索用时 15 毫秒
41.
C. Kourkoumelis L.K. Resvanis T.A. Filippas E. Fokitis A.M. Cnops S. Iwata R.B. Palmer D.C. Rahm P. Rehak I. Stumer C.W. Fabjan T. Fields D. Lissauer I. Mannelli P. Mouzourakis A. Nappi W.J. Willis M. Goldberg 《Physics letters. [Part B]》1979,84(2):277-280
The inclusive η production cross section at the CERN ISR has been measured for pT values of up to 11 GeV/c. We find that the cross-section ratio has an average value of 0.55 ± 0.07 and varies little with pT. 相似文献
42.
Y. Osamura S. Yamabe F. Hirota H. Hosoya S. Iwata H. Kashiwagi K. Morokuma M. Togasi S. Obara K. Tanaka K. Ohno 《International journal of quantum chemistry》1980,18(2):393-396
A brief account of a quantum chemistry literature data base (QCLDB ) is described, which contains the key information of about 2000 papers of ab initio calculations of atoms and molecules published in 1977–1979. The QCLDB is stored in a computer and can be sorted and rearranged into author and substance indices. Selection of the items for each paper in a computer-readable data base is discussed. 相似文献
43.
The divalent ruthenium complexes bearing benzene, mesitylene triphenylbenzene as a π-ligand were prepared and their catalytic activity for olefin hydrogenation was examined. They showed activity in the presence of a small amount of base. Particularly, the complex with triphenylbenzene was found to have extremely high activity. Discussion here is on a role of a π-arene ligand in the activity. 相似文献
44.
Dutz H Helbing K Krimmer J Speckner T Zeitler G Ahrens J Altieri S Annand JR Anton G Arends HJ Beck R Bock A Bradtke C Braghieri A v Drachenfels W Frommberger F Godo M Goertz S Grabmayr P Hasegawa S Hansen K Harmsen J Heid E Hillert W Holvoet H Horikawa N Iwata T Van Hoorebeke L d'Hose N Jennewein P Kiel B Klein F Kondratiev R Lang M Lannoy B Leukel R Lisin V Menze D Meyer W Michel T Naumann J Panzeri A Pedroni P Pinelli T Preobrajenski I Radtke E Reicherz G Rohlof C Rostomyan T Sauer M 《Physical review letters》2003,91(19):192001
To verify the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for the first time experimentally, we measured the helicity dependent total photoabsorption cross section with circularly polarized real photons and longitudinally polarized nucleons in the photon energy range 0.68-1.82 GeV with the tagged photon facility at ELSA. The experiment was carried out with a 4pi detection system, a circularly polarized tagged photon beam, and a frozen spin polarized proton target. The contribution to the GDH sum rule in this photon energy range is [49.9+/-2.4(stat)+/-2.2(syst)] microb. 相似文献
45.
Zegers RG Sumihama M Ahn DS Ahn JK Akimune H Asano Y Chang WC Daté S Ejiri H Fujimura H Fujiwara M Hicks K Hotta T Imai K Ishikawa T Iwata T Kawai H Kim ZY Kino K Kohri H Kumagai N Makino S Matsumura T Matsuoka N Mibe T Miwa K Miyabe M Miyachi Y Morita M Muramatsu N Nakano T Niiyama M Nomachi M Ohashi Y Ooba T Ohkuma H Oshuev DS Rangacharyulu C Sakaguchi A Sasaki T Shagin PM Shiino Y Shimizu H Sugaya Y Toyokawa H Wakai A Wang CW Wang SC Yonehara K Yorita T Yoshimura M Yosoi M 《Physical review letters》2003,91(9):092001
Beam polarization asymmetries for the p(gamma-->,K+)Lambda and p(gamma-->,K+)Sigma(0) reactions are measured for the first time for E(gamma)=1.5-2.4 GeV and 0.6相似文献
46.
Modern modeling approaches for circuit analysis lead to differential-algebraic equations (DAEs). The index of a DAE is a measure
of the degree of numerical difficulty. In general, the higher the index is, the more difficult it is to solve the DAE. The
index of the DAE arising from the modified nodal analysis (MNA) is determined uniquely by the structure of the circuit. Instead,
we consider a broader class of analysis method called the hybrid analysis. For linear time-invariant electric circuits, we
devise a combinatorial algorithm for finding an optimal hybrid analysis in which the index of the DAE to be solved attains
the minimum. The optimal hybrid analysis often results in a DAE with lower index than MNA.
相似文献
47.
Takashi Kamimura Masaki Sato Takao Iwata 《Journal of magnetism and magnetic materials》1987,70(1-3):209-210
Transitions related to the spin-glass phase in Mn1−xTixSb
are revisited from the nonlinear ac susceptibility. Near the tricritical point (x≈0.8), the transition between ferromagnetic and reentrant spin-glass states is sharp. At x0.8, an anomally is found slightly above the temperature of usual spin-glass freezing. 相似文献
48.
49.
50.
In this study, a cation-exchange resin (CEX) of the K+-form, i.e., an enhancer resin, is used as a postcolumn conductimetric enhancer in the ion-exclusion chromatography of aliphatic carboxylic acids. The enhancer resin is filled in the switching valve of an ion chromatograph; this valve is usually used as a suppressor valve in ion-exchange chromatography. An aliphatic carboxylic acid (e.g., CH3COOH) separated by a weakly acidic CEX column of the H+-form converts into that of the K+-form (e.g., CH3COOK) by passing through the enhancer resin. In contrast, the background conductivity decreases because a strong acid (e.g., HNO3) with a higher conductimetric response in an eluent converts into a salt (e.g., KNO3) with a lower conductimetric response. Since the pH of the eluent containing the resin enhancer increases from 3.27 to 5.85, the enhancer accelerates the dissociations of analyte acids. Consequently, peak heights and peak areas of aliphatic carboxylic acids (e.g., acetic acid, propionic acid, butyric acid, and valeric acid) with the enhancer resin are 6.3-8.0 times higher and 7.2-9.2 times larger, respectively, than those without the enhancer resin. Calibrations of peak areas for injected analytes are linear in the concentration range of 0.01-1.0 mM. The detection limits (signal-to-noise ratio = 3) range from 0.10 μM to 0.39 μM in this system, as opposed to those in the range of 0.24-7.1 μM in the separation column alone. The developed system is successfully applied to the determination of aliphatic carboxylic acids in a chicken droppings sample. 相似文献