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排序方式: 共有1112条查询结果,搜索用时 31 毫秒
91.
Raphaël Grougnet Prokopios Magiatis Sofia Mitaku Alexios‐Leandros Skaltsounis Pierre Cabalion François Tillequin Sylvie Michel 《Helvetica chimica acta》2011,94(4):656-661
Three new dammarane triterpenoids, gardaubryones A–C ( 1 – 3 ), were isolated from the gum collected on the aerial parts of Gardenia aubryi Vieill ., together with the known compounds hydroxydammarenone II ( 4 ), ocotillone ( 5 ), cabraleone, and hollongdione. The structures of the novel compounds were established on the basis of mass spectrometry, NMR experiments, and chemical‐correlation reactions. 相似文献
92.
Ugo Morin 《Annali di Matematica Pura ed Applicata》1942,21(1):113-155
Sunto Delle varietà algebriche a3 dimensioni (non coni o luoghi di ∞1 piani) a curve sezioni di genere π=3 si danno i tipi proiettivamente distinti. Questi, ad eccezione dellaV
3
(4)
dell'S
4, sono razionali. I loro sistemi rappresentativi forniscono tutti i sistemi lineari di superficie dell'S
3, cremonianamente distinti, a curva caratteristica di genere3, semplici e di grado >4. 相似文献
93.
Laurent Aubry Thierry Sayd Claude Ferreira Christophe Chambon Annie Vnien Sylvie Blinet Marie Bourin Anglique Travel Maeva Halgrain Vronique Sant-Lhoutellier Laetitia Thron 《Molecules (Basel, Switzerland)》2021,26(12)
The marketing of poultry livers is only authorized as fresh, frozen, or deep-frozen. The higher consumer demand for these products for a short period of time may lead to the marketing of frozen–thawed poultry livers: this constitutes fraud. The aim of this study was to design a method for distinguishing frozen–thawed livers from fresh livers. For this, the spectral fingerprint of liver proteins was acquired using Matrix-Assisted Laser Dissociation Ionization-Time-Of-Flight mass spectrometry. The spectra were analyzed using the chemometrics approach. First, principal component analysis studied the expected variability of commercial conditions before and after freezing–thawing. Then, the discriminant power of spectral fingerprint of liver proteins was assessed using supervised model generation. The combined approach of mass spectrometry and chemometrics successfully described the evolution of protein profile during storage time, before and after freezing-thawing, and successfully discriminated the fresh and frozen–thawed livers. These results are promising in terms of fraud detection, providing an opportunity for implementation of a reference method for agencies to fight fraud. 相似文献
94.
95.
Makhlouf Amoura Cécile Roux Sylvie Masse Nathalie Steunou Thibaud Coradin 《Comptes Rendus Chimie》2010,13(1-2):52-57
Zirconium oxyhydroxide nanoparticles prepared by an aqueous route were evaluated for Escherichia coli bacteria encapsulation. A low viability rate was measured 24 hours after immobilization that could be attributed to nanoparticle cytotoxicity. Moreover, the presence of glycerol, a long-term cell-preserving molecule, hindered gel formation, probably due to its adsorption on the nanoparticle surface. A comparison with boehmite and ferrihydrite gels previously synthesized following a similar aqueous colloidal route suggests that the generalization of this method will rely on a careful control of the nanoparticle surface reactivity and may require surface chemical modification. 相似文献
96.
Ugo Morin 《Annali di Matematica Pura ed Applicata》1940,19(1):257-288
Sunto. Si assegnano i tipi cremonianamente distinti di sistemi lineari completi, semplici, irriducibili di superficie algebriche
dello spazioS
3 a curva-caratteristica (variabile) di genereπ=2. Questi si distribuiscono in25 famiglie, delle quali si danno la dimensione, l'ordine minimo, ecc. e la rappresentazione analitica. 相似文献
97.
98.
Characterization of Linear Structures 总被引:2,自引:0,他引:2
Sylvie Dubuc 《Designs, Codes and Cryptography》2001,22(1):33-45
We study the notionof linear structure of a function defined from F
mto F
n, and in particular of a Boolean function.We characterize the existence of linear structures by means ofthe Fourier transform of the function. For Boolean functions,this characterization can be stated in a simpler way. Finally,we give some constructions of resilient Boolean functions whichhave no linear structure. 相似文献
99.
Sylvie Guerre 《Israel Journal of Mathematics》1986,53(2):191-208
We prove that every normalized sequence inL
p
, weakly null ifp>2 and equivalent to the unit vector basis ofl
2 if 1≦p<2, has for allε>0 a subsequence which is 2(1+ε)-symmetric. This result was known forp=1 (H.P. Rosenthal) andp∈N (W.B. Johnson, B. Maurey, G. Shechtman, L. Tzafriri). Here, we use the techniques of stability which were introduced by
J.L. Krivine and B. Maurey: as well as providing new results, this approach unifies and simplifies previous known results.
相似文献
100.