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71.
It is pointed out that all models in which particle production occurs via an intermediate step of isotropically decaying fireballs, predict the existence of the positive short-range component in two-particle inclusive correlations. The correlation lenght is predicted to be about one, in agreement with existing data. 相似文献
72.
T. Anticic B. Baatar J. Bartke L. Betev H. Bia?kowska B. Boimska J. Bracinik V. Cerny O. Chvala J. Dolejsi V. Eckardt H. G. Fischer Z. Fodor E. G?adysz K. Kadija A. Karev V. Kolesnikov M. Kowalski M. Kreps M. Makariev A. Malakhov M. Mateev G. Melkumov A. Rybicki N. Schmitz P. Seyboth T. Susa P. Szymanski V. Trubnikov D. Varga G. Vesztergombi S. Wenig 《The European Physical Journal C - Particles and Fields》2010,68(1-2):1-73
New data on the production of charged kaons in p+p interactions are presented. The data come from a sample of 4.8 million inelastic events obtained with the NA49 detector at the CERN SPS at 158 GeV/c beam momentum. The kaons are identified by energy loss in a large TPC tracking system. Inclusive invariant cross sections are obtained in intervals from 0 to 1.7 GeV/c in transverse momentum and from 0 to 0.5 in Feynman x. Using these data as a reference, a new evaluation of the energy dependence of kaon production, including neutral kaons, is conducted over a range from 3 GeV to $\mathrm{p}+\overline{\mathrm{p}}$ collider energies. 相似文献
73.
The effect of interferents present on the opposite side of the Pb2+-selective membrane has been studied for both internal solution and all-solid-state sensors with a conducting polymer (CP)
transducer. For interferents with moderate selectivity coefficients (sodium cations) present in the internal solution or in
the CP transducer phase, super-Nernstian responses were obtained. For sensors containing strongly discriminated interferents
(lithium ions), however, responses typical of conventional electrodes are observed, despite the low activity of primary ions
on the opposite side of the membrane. This effect is attributed to hindered incorporation of interfering ions into the membrane,
which also impairs the long term stability of the potential. Because of the relatively small absolute amounts of interferents
in the transducer of all-solid-state sensors, their exchange for primary ions occurs quickly. Thus, transformation of the
sensor to one with a micromolar detection limit and high potential stability is observed.
相似文献
74.
Katarzyna Białas 《PAMM》2010,10(1):357-358
The major objective of this study is to show how to carry out the process of structural and parametrical synthesis that is understood as a method intended to seek for the structure and parameters of a discrete model of the system with active suppression of vibrations. Active components are implemented as mechanical components with kinematic excitations. The other objective is to analyze how the active subsystem interacts with the overall investigated structure. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
75.
For an arbitrary countable field, we construct an associative algebra that is graded, generated by finitely many degree-1 elements, is Jacobson radical, is not nil, is prime, is not PI, and has Gel’fand-Kirillov dimension two. This refutes a conjecture incorrectly attributed to Goodearl. 相似文献
76.
Let K be a field and let A be a finitely generated prime K-algebra. We generalize a result of Smith and Zhang, showing that if A is not PI and does not have a locally nilpotent ideal, then the extended centre of A has transcendence degree at most GKdim(A) ?2 over K. As a consequence, we are able to show that if A is a prime K-algebra of quadratic growth, then either the extended centre is algebraic over K or A is PI. Finally, we give an example of a finitely generated non-PI prime K-algebra of GK dimension 2 with a locally nilpotent ideal such that the extended centre has infinite transcendence degree over K. 相似文献
77.
Agata Konarska Elbieta Weryszko-Chmielewska Anna Matysik-Wo
niak Aneta Sulborska Beata Polak Marta Dmitruk Krystyna Piotrowska-Weryszko Beata Stefaczyk Robert Rejdak 《Molecules (Basel, Switzerland)》2021,26(14)
The aim of this study was to conduct a histochemical analysis to localize lipids, terpenes, essential oil, and iridoids in the trichomes of the L. album subsp. album corolla. Morphometric examinations of individual trichome types were performed. Light and scanning electron microscopy techniques were used to show the micromorphology and localization of lipophilic compounds and iridoids in secretory trichomes with the use of histochemical tests. Additionally, the content of essential oil and its components were determined using gas chromatography-mass spectrometry (GC-MS). Qualitative analyses of triterpenes carried out using high-performance thin-layer chromatography (HPTLC) coupled with densitometric detection, and the iridoid content expressed as aucubin was examined with spectrophotometric techniques. We showed the presence of iridoids and different lipophilic compounds in papillae and glandular and non-glandular trichomes. On average, the flowers of L. album subsp. album yielded 0.04 mL/kg of essential oil, which was dominated by aldehydes, sesquiterpenes, and alkanes. The extract of the L. album subsp. album corolla contained 1.5 × 10−3 ± 4.3 × 10−4 mg/mL of iridoid aucubin and three triterpenes: oleanolic acid, β-amyrin, and β-amyrin acetate. Aucubin and β-amyrin acetate were detected for the first time. We suggest the use of L. album subsp. album flowers as supplements in human nutrition. 相似文献
78.
Ewa Pejcz Sabina Lachowicz-Winiewska Paulina Nowicka Agata Wojciechowicz-Budzisz Radosaw Spychaj Zygmunt Gil 《Molecules (Basel, Switzerland)》2021,26(14)
Inoculation of sourdough allows the fermentation medium to be dominated by desired microorganisms, which enables determining the kinetics of the conversion of chemical compounds by individual microorganisms. This knowledge may allow the design of functional food products with health features dedicated to consumers with special needs. The aim of the study was to assess the dynamics of transformations of fermentable oligosaccharide, disaccharide, monosaccharide and polyol (FODMAP) compounds from wheat flour as well as their antioxidant activity during inoculated and spontaneous sourdough fermentation. The FODMAP content in grain products was determined by the fructan content with negligible amounts of sugars and polyols. To produce a low-FODMAP cereal product, the fermentation time is essential. The 72 h fermentation time of L. plantarum-inoculated sourdough reduced the FODMAP content by 91%. The sourdough fermentation time of at least 72 h also positively influenced the content of polyphenols and antioxidant activity, regardless of the type of fermentation. The inoculation of both L. plantarum and L. casei contributed to a similar degree to the reduction in FODMAP in sourdough compared to spontaneous fermentation. 相似文献
79.
Agata Semeniuk Justyna Kalinowska-Tluscik Wojciech Nitek Barbara J. Oleksyn 《Journal of chemical crystallography》2008,38(5):333-338
Abstract The crystal structure of hydroxychloroquine sulfate (OHClQ) was determined in order to compare its conformation and intermolecular
interactions to those in the crystalline chloroquine phosphate (ClQP) and quinine salicylate (QSal) monohydrate. The crystals
of OHClQ are monoclinic with the space group P21/c and unit-cell dimensions: a = 10.4966(1) ?, b = 8.8056(1) ?, c = 21.8603(3) ?, β = 101.074(1)°. The quinoline antimalarial drugs may interact with their putative receptors by formation
of characteristic hydrogen-bonded rings. The protonated nitrogen atoms and/or hydroxyl groups of the drug cation are proton
donors, while the oxygen atoms of anions are proton acceptors. Water molecules may intermediate in these interactions.
Graphical Abstract Hydroxychloroquine sulfate is a drug used in the treatment of malaria and rheumatic diseases. The X-ray structure analysis
shows an important role of intermolecular hydrogen bonds in the crystal architecture. Comparison with chloroquine phosphate
and quinine salicylate indicates that the organization of the drug cations is determined by the anions.
相似文献
80.
Synthesis of some new triazoles fused to triazoles 5a–c or thiadiazoles 6a–c and the thiol‐thione tautomeric equilibrium study of the title compounds are reported. The “rule of five” and complementary criteria of pharmacokinetic properties were determined to predict whether these compounds are orally bioavailable. Semiempirical parameterizations have been critically benchmarked for the thiol‐thione tautomeric equilibrium against the DFT calculations. It was shown that unlike the AM1 and PM3 Hamiltonians, which erroneously predict higher stability of the thiol tautomer, the newly developed RM1 Hamiltonian, on the other hand, predicts energetics of this equilibrium in excellent agreement with the DFT results. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:713–718, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20499 相似文献