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51.
Elena Piacenza Delia Francesca Chillura Martino Luciano Cinquanta Pellegrino Conte Paolo Lo Meo 《Magnetic resonance in chemistry : MRC》2022,60(3):369-385
A set of commercial milk and Sicilian cheeses was analysed by a combination of fast field cycling (FFC) nuclear magnetic resonance (NMR) relaxometry and chemometrics. The NMR dispersion (NMRD) curves were successfully analysed with a mathematical model applied on Parmigiano–Reggiano (PR) cheese. Regression parameters were led back to the molecular components of cheeses (water trapped in casein micelles, proteins and fats) and milk samples (water belonging to hydration shells around dispersed colloidal particles of different sizes and bulk water). The application of chemometric analysis on relaxometric data enabled differentiating milk from cheeses and revealing differences within the two sample groups of either cheeses or milk samples. Marked differences among cheeses were evidenced by statistical analysis of the sole quadrupolar peaks parameters, suggesting that these contain information on the nature of the milk used during cheese production. Hence, combination of FFC NMR and chemometrics represents a powerful tool to investigate alterations in dairy products. 相似文献
52.
Delia Ionescu-Kruse 《Journal of Mathematical Fluid Mechanics》2013,15(1):41-54
In order to obtain quite precise information about the shape of the particle paths below small-amplitude gravity waves travelling on irrotational deep water, analytic solutions of the nonlinear differential equation system describing the particle motion are provided. All these solutions are not closed curves. Some particle trajectories are peakon-like, others can be expressed with the aid of the Jacobi elliptic functions or with the aid of the hyperelliptic functions. Remarks on the stagnation points of the small-amplitude irrotational deep-water waves are also made. 相似文献
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Delia Ionescu-Kruse 《Nonlinear Analysis: Real World Applications》2010,11(4):2989-3000
Two-dimensional periodic surface waves propagating under the combined influence of gravity and surface tension on water of finite depth are considered. Within the framework of small-amplitude waves, we find the exact solutions of the nonlinear differential equation system which describes the particle motion in the considered case, and we describe the possible particle trajectories. The required computations involve elliptic integrals of the first kind, the Legendre normal form and a solvable Abel differential equation of the second kind. Some graphs of the results are included. 相似文献
55.
Piacenza Elena Presentato Alessandro Alduina Rosa Scurria Antonino Pagliaro Mario Albanese Lorenzo Meneguzzo Francesco Ciriminna Rosaria Chillura Martino Delia F. 《Cellulose (London, England)》2022,29(10):5779-5802
Cellulose - Pectin recovered via hydrodynamic cavitation (IntegroPectin) from lemon and grapefruit agri-food waste intrinsically containing antimicrobial bioactive substances (flavonoids, phenolic... 相似文献
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Thomas J. Delia Jennifer M. Schomaker Alvin S. Kalinda 《Journal of heterocyclic chemistry》2006,43(1):127-131
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Fabrication of an amperometric-rotating biosensor for the enzymatic determination of cholesterol is reported. The assay utilizes a combination of three enzymes: cholesterol esterase (ChE), cholesterol oxidase (ChOx) and peroxidase (HRP); which were co-immobilizing on a rotatory disk. The method is developed by the use of a glassy carbon electrode as detector versus Ag/AgCl/3 M NaCl in conjunction with a soluble-redox mediator 4-tert-butylcatechol (TBC). ChE converts esterified cholesterol to free cholesterol, which is then oxidized by ChOx with hydrogen peroxide as product. TBC is converted to 4-tert-butylbenzoquinone (TBB) by hydrogen peroxide, catalyzed by HRP, and the glassy carbon electrode responds to the TBB concentration. The system has integrated a micro packed-column with immobilized ascorbate oxidase (AAOx) that works as prereactor to eliminate l-ascorbic acid (AA) interference. This method could be used to determine total cholesterol concentration in the range 1.2 μM-1 mM (r = 0.999). A fast response time of 2 min has been observed with this amperometric-rotating biosensor. Lifetime is up to 25 days of use. The calculated detection limits was 11.9 nM. Reproducibility assays were made using repetitive standards solutions (n = 5) and the percentage standard error was less than 4%. 相似文献
59.
Ruiz J Lorenzo J Sanglas L Cutillas N Vicente C Villa MD Avilés FX López G Moreno V Pérez J Bautista D 《Inorganic chemistry》2006,45(16):6347-6360
Pd(II) and Pt(II) complexes with the anions of the model nucleobases 1-methylthymine (1-MethyH), 1-methyluracil (1-MeuraH), and 1-methylcytosine (1-MecytH) of the types [Pd(dmba)(mu-L)]2 [dmba = N,C-chelating 2-((dimethylamino)methyl)phenyl; L = 1-Methy, 1-Meura or 1-Mecyt] and [M(dmba)(L)(L')] [L = 1-Methy or 1-Meura; L' = PPh(3) (M = Pd or Pt), DMSO (M = Pt)] have been obtained. Palladium complexes of the types [Pd(C6F5)(N-N)(L)] [L = 1-Methy or 1-Meura; N-N = N,N,N',N'-tetramethylethylenediamine (tmeda), 2,2'-bipyridine (bpy), or 4,4'-dimethyl-2,2'-bipyridine (Me2bpy)] and [NBu4][Pd(C6F5)(1-Methy)2(H2O)] have also been prepared. The crystal structures of [Pd(dmba)(mu-1-Methy)]2, [Pd(dmba)(mu-1-Mecyt)]2.2CHCl3, [Pd(dmba)(1-Methy)(PPh3)].3CHCl3, [Pt(dmba)(1-Methy)(PPh3)], [Pd(tmeda)(C6F5)(1-Methy)], and [NBu4][Pd(C6F5)(1-Methy)2(H2O)].H2O have been established by X-ray diffraction. The DNA adduct formation of the new platinum complexes synthesized was followed by circular dichroism and electrophoretic mobility. Atomic force microscopy images of the modifications caused by the platinum complexes on plasmid DNA pBR322 were also obtained. Values of IC50 were also calculated for the new platinum complexes against the tumor cell line HL-60. All the new platinum complexes were more active than cisplatin (up to 20-fold in some cases). 相似文献
60.
A one-step synthesis of 2,4-disubstituted-pyrimido[4,5-d]pyrimidines has been investigated. Cyclization of 6-amino-2,4-disubstituted-pyrimidines with formamide as solvent and reagent affords the title compounds in 50-70% yield. Strongly electron-donating groups are required. Based on model compounds, a pathway for the cyclization is suggested. The method is an improvement on previous methods of synthesis, albeit a limited one. 相似文献