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91.
We force and construct a model in which level by level equivalence between strong compactness and supercompactness holds,
along with a strong form of diamond and a version of square consistent with supercompactness. This generalises a result due
to the first author. There are no restrictions in our model on the structure of the class of supercompact cardinals.
A. W. Apter’s research was partially supported by PSC-CUNY Grants and CUNY Collaborative Incentive Grants. J. Cummings’s research
was partially supported by NSF Grant DMS-0400982. 相似文献
92.
It is proved that there is a certain degree of independencebetween stationary reflection phenomena at different cofinalities. 相似文献
93.
The development and evaluation of a kinetic method for the simultaneous quantification of methemoglobin and hemoglobin is described. A unique feature of the reaction/monitoring system is that the two species produce signals that change in opposite directions. Attempts to optimize the reaction conditions, procedures for preparing reliable standards, a new multiwavelength method used for comparison purposes and results for synthetic standards and blood samples to which known amounts of methemoglobin are added are described. Combined effects of competing directions of signal change, large concentration differences and conditions required for pseudo-first-order behavior results in a relativity narrowly defined set of conditions that permit simultaneous determinations. Even so, results for methemoglobin were in reasonable agreement between the kinetic and spectrophotometric methods (slope 1.05, intercept 0.17 mmol l?1); difficulties in achieving pseudo-first-order behavior yielded less reliable results for hemoglobin with a least-squares slope of 1.16 for a comparison of results by kinetic and spectrophotometric methods. This latter problem had an adverse effect on comparison of percentages of methemoglobin in samples even though concentration values were in good agreement. 相似文献
94.
Amperometric detection of phenolic compounds by polypyrrole-based composite carbon paste electrodes 总被引:1,自引:0,他引:1
Mailley P Cummings EA Mailley S Cosnier S Eggins BR McAdams E 《Bioelectrochemistry (Amsterdam, Netherlands)》2004,63(1-2):291-296
This contribution describes new composite carbon paste electrodes (CPEs) for the determination of phenolic compounds. The composite CPEs were prepared by in situ generation of polypyrrole (PPy) within a paste containing the enzyme polyphenol oxidase (PPO). The best paste composition (enzyme/pyrrole monomer/carbon particles/Nujol) was determined for a model enzyme, glucose oxidase (GOx) according to the enzymatic activity of the resulting electrodes and to the enzyme leakage from the paste during storage in phosphate buffer. The in situ electrogenerated PPy improves the enzyme immobilisation within the paste since practically no enzyme was lost in solution after 72 h of immersion. Moreover, the enzyme activity remains particularly stable under storage since the biocomposite structure conserves 80% of its activity after 1 month of storage. Following the optimisation of the paste composition, PPO-based carbon paste biosensors were prepared and presented excellent analytical properties toward catechol detection with a sensitivity of 4.7 A M(-1) cm(-2) and a response time lower than 20 s. The resulting biosensors were applied to the determination of polyphenolic compounds (e.g., epicatechin and ferulic acid). 相似文献
95.
Amita Gupta Alexei Yu Ganin Parmanand Sharma Vikrant Agnihotri LM Belova KV Rao Mikhail E Kozlov AA Zakhidov RH Baughman 《Pramana》2002,58(5-6):1051-1059
We present studies of novel nanocomposites of BiNi impregnated into the structure of opals as well as inverse opals. Atomic force microscopy and high resolution elemental analyses show
a highly ordered structure and uniform distribution of the BiNi filler in the matrix. These BiNi-based nanocomposites are
found to exhibit distinct ferromagnetic-like ordering with transition temperature of about 675 K. As far as we know there
exists no report in literature on any BiNi compound which is magnetic. 相似文献
96.
Stepanyan S Hicks K Carman DS Pasyuk E Schumacher RA Smith ES Tedeschi DJ Todor L Adams G Ambrozewicz P Anciant E Anghinolfi M Asavapibhop B Audit G Avakian H Bagdasaryan H Ball JP Barrow SP Battaglieri M Beard K Bektasoglu M Bellis M Berman BL Bianchi N Biselli AS Boiarinov S Bouchigny S Bradford R Branford D Briscoe WJ Brooks WK Burkert VD Butuceanu C Calarco JR Carnahan B Chen S Ciciani L Cole PL Coleman A Cords D Corvisiero P Crabb D Crannell H Cummings JP De Sanctis E Degtyarenko PV 《Physical review letters》2003,91(25):252001
In an exclusive measurement of the reaction gammad-->K(+)K(-)pn, a narrow peak that can be attributed to an exotic baryon with strangeness S=+1 is seen in the K(+)n invariant mass spectrum. The peak is at 1.542+/-0.005 GeV/c(2) with a measured width of 0.021 GeV/c(2) FWHM, which is largely determined by experimental mass resolution. The statistical significance of the peak is (5.2+/-0.6)sigma. The mass and width of the observed peak are consistent with recent reports of a narrow S=+1 baryon by other experimental groups. 相似文献
97.
Carman DS Joo K Mestayer MD Raue BA Adams G Ambrozewicz P Anciant E Anghinolfi M Armstrong DS Asavapibhop B Audit G Auger T Avakian H Bagdasaryan H Ball JP Barrow SP Battaglieri M Beard K Bektasoglu M Bellis M Bennhold C Bianchi N Biselli AS Boiarinov S Bonner BE Bouchigny S Bradford R Branford D Briscoe WJ Brooks WK Burkert VD Butuceanu C Calarco JR Carnahan B Cazes A Cetina C Ciciani L Clark R Cole PL Coleman A Cords D Corvisiero P Crabb D Crannell H Cummings JP DeSanctis E Degtyarenko PV 《Physical review letters》2003,90(13):131804
The first measurements of the transferred polarization for the exclusive e-->p-->e(')K+Lambda--> reaction have been performed at Jefferson Laboratory using the CLAS spectrometer. A 2.567 GeV beam was used to measure the hyperon polarization over Q2 from 0.3 to 1.5 (GeV/c)(2), W from 1.6 to 2.15 GeV, and over the full K+ center-of-mass angular range. Comparison with predictions of hadrodynamic models indicates strong sensitivity to the underlying resonance contributions. A nonrelativistic quark-model interpretation of our data suggests that the ssmacr; quark pair is produced with spins predominantly antialigned. Implications for the validity of the most widely used quark-pair creation operator are discussed. 相似文献
98.
We report new detailed density profile measurements in expanding strongly coupled neutral calcium plasmas. Using laser-induced fluorescence techniques, we determine plasma densities in the range of 10(5) to 10(9) cm(-3) to with a time resolution limit as small as 7 ns. Strong coupling in the plasma ions is inferred directly from the fluorescence signals. Evidence for strong coupling at late times is presented, confirming a recent theoretical result. 相似文献
99.
Strauch S Berman BL Adams G Ambrozewicz P Anghinolfi M Asavapibhop B Asryan G Audit G Avakian H Bagdasaryan H Baillie N Ball JP Baltzell NA Barrow S Batourine V Battaglieri M Beard K Bedlinskiy I Bektasoglu M Bellis M Benmouna N Bennhold C Biselli AS Boiarinov S Bouchigny S Bradford R Branford D Briscoe WJ Brooks WK Bültmann S Burkert VD Butuceanu C Calarco JR Careccia SL Carman DS Carnahan B Chen S Cole PL Coleman A Coltharp P Cords D Corvisiero P Crabb D Crannell H Cummings JP Degtyarenko PV 《Physical review letters》2005,95(16):162003
100.
We consider scalar-valued matrix functions for n×n matrices A=(aij) defined by Where G is a subgroup of Sn the group of permutations on n letters, and χ is a linear character of G. Two such functions are the permanent and the determinant. A function (1) is multiplicative on a semigroup S of n×n matrices if d(AB)=d(A)d(B) AB∈S.
With mild restrictions on the underlying scalar ring we show that every element of a semigroup containing the diagonal matrices on which (1) is multiplicative can have at most one nonzero diagonal(i.e., diagonal with all nonzero entries)and conversely, provided that χ is the principal character(χ≡1). 相似文献
With mild restrictions on the underlying scalar ring we show that every element of a semigroup containing the diagonal matrices on which (1) is multiplicative can have at most one nonzero diagonal(i.e., diagonal with all nonzero entries)and conversely, provided that χ is the principal character(χ≡1). 相似文献