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The ternary edible films based on commercial or bio-chemical chitosan (CCh or BCh) and starch (S) with different concentration of gallic acid (GA) were produced by casting. This work analyzed the effect of different type of Ch and GA concentrations (1.25 mg/gTB and 2.5 mg/gTB) on the rheological properties of the film-forming solutions, as well as physicochemical (thickness, moisture content, swelling index, water vapor permeability (WVP), tensile strength, microstructure, opacity, and color) and antioxidant properties of the edible films themselves. The chemical cross-linking between the GA and Ch into the edible films of biopolymers could form of ester linkages between the carboxyl groups of GA and the hydroxyl groups of Ch. Results showed that the ternary edible films of BCh-S-GA5.0 resulted with a positive effect on their rheological (η0, λ, and p), physicochemical (WVP, swelling, tensile strength, microstructure) and antioxidant properties. The greatest incorporation of polyphenol into the BCh-S-GA5.0 films greatly reduced WVP and swelling values in approximately 61.01% and 23%, respectively also the tensile strength value increased to 37.372 MPa. The ternary edible films developed in this study showed many desirable characteristics, which could potentially be used as bioactive packaging films for food applications.

Graphical abstract, Highlights • Ultrasound is a fast method for phenolic compounds recovery from C. chinense leaves. • Solvent polarity has a strong effect on the recovery of phenolic compounds. • Dielectric constant was propose to predict the most appropriate solvent for phenolic extraction. • Antioxidant activity correlates with total phenolic content of C. chinense leaves extracts. • Identification of phenolic compounds was performed by UPLC-PDA-ESI-MS/MS., Phenolic compounds are secondary metabolites involved in plant adaptation processes. The development of extraction procedures, quantification, and identification of this compounds in habanero pepper (Capsicum chinense) leaves can provide information about their accumulation and possible biological function. The main objective of this work was to study the effect of the UAE method and the polarity of different extraction solvents on the recovery of phenolic compounds from C. chinense leaves. Quantification of the total phenolic content (TPC), antioxidant activity (AA) by ABTS+ and DPPH radical inhibition methods, and the relation between the dielectric constant (ε) as polarity parameter of the solvents and TPC using Weibull and Gaussian distribution models was analyzed. The major phenolic compounds in C. chinense leaves extracts were identified and quantified by UPLC-PDA-ESI-MS/MS. The highest recovery of TPC (24.39 ± 2.41 mg GAE g−1 dry wt) was obtained using MeOH (50%) by UAE method. Correlations between TPC and AA of 0.89 and 0.91 were found for both radical inhibition methods (ABTS+ and DPPH). The Weibull and Gaussian models showed high regression values (0.93 to 0.95) suggesting that the highest phenolic compounds recovery is obtained using solvents with “ε” values between 35 and 52 by UAE. The major compounds were identified as N-caffeoyl putrescine, apigenin, luteolin and diosmetin derivatives. The models presented are proposed as a useful tool to predict the appropriate solvent composition for the extraction of phenolic compounds from C. chinense leaves by UAE based on the “ε” of the solvents for future metabolomic studies.

Cactus pear (Opuntia sp.) is a highly perishable fruit that starts to deteriorate after several days of storage at room temperature. After two weeks at room temperature, 70% of the fruit shows signs of deterioration. Cactus pear quality for stored pears depends on harvest techniques and on practices for prolonging shelf life. A pneumatic cauterizing machine with a resistive heating element was used to seal cactus pears on their peduncle. More effective contact between the heater element and fruit was obtained after cutting the peduncle. Internal pulp temperature was measured with NTC thermistors and it was found that after heating at 200 °C for 30 s, pulp temperature increased to 60 °C. Surface temperature was measured with a thermal infrared camera. Cactus pear shelf life, water loss, firmness and ° Brix were evaluated using piston pressures of 50, 100, 150 and 200 kPa during 30 s at cauterizing temperatures of 150, 180, 200 and 240 °C. The best shelf life was obtained after pressing the fruit with 100 kPa during 30 s at a temperature of 200 °C. Thirty-seven days after being cauterized, fruits began to rot, and half of the fruit was not marketable after 63 days. Pulp firmness decreased by 81% after 60 storage days, and soluble solids increased by 105%. Pears that did not seal properly were detected using thermal imaging three days after cauterizing. Pears were sliced and cauterized again unless the rotting area was over 50% and firmness lower than 15 N cm−2.

The physicochemical characteristics, intrinsic viscosity, adsorption dynamics and emulsifying properties of two hawthorn accessions pectins (HP50 and HP55) were evaluated and compared to those obtained for commercial citrus pectin (CP). Mark-Houwink-Kuhn-Sakurada coefficients, aMHKS = 0.71 ± 0.02 and kMHKS = 5.08 × 10− 3 ± 2 × 10− 4 g dL− 1 were obtained from intrinsic viscosity data. The diffusion (Kdiff), penetration (K1) and the rearrangement (K2) constants were determined from adsorption dynamics data of the pectins at the canola oil-water interface. Kdiff was higher and K1 was lower for HP50 than for HP55 and for CP. These results had bearing on the stability of oil-in-water emulsions. Higher Kdiff produced smaller initial droplet sizes, due to the faster diffusion of molecules to the interface, while lower K1 produced longer-term stability, as a more consolidated and stronger interfacial film was formed faster, making arduous the penetration of newly arriving molecules through the monolayer. The rate of creaming was lower the smaller was the initial droplet size and the higher the apparent viscosity of the emulsions.

The coupling of two s-wave superconductors through a small magnetic dot is discussed. Assuming that the dot charging energy is small compared to the superconducting gap, $E_c\ll \Delta$, and that the moment of the dot is classical, we develop a simple theory of transport through the dot. The presence of the magnetic dot will position Andreev bound states within the superconducting gap at energies tunable with the magnetic properties of the dot. Studying the Josephson coupling it is shown that the constructed junction can be tuned from a "0" to a "$\pi$"-junction via a degenerate two-level state either by changing the magnetic moment of the dot or by changing temperature. Furthermore, it is shown that details of the magnetic dot can be extracted from the sub-harmonic structure in the current-voltage characteristics of the junction., Comment: 5 pages, 4 figures, paper presented at the conference SDP 2001 in Tokyo on June 25

We present a theoretical approach to the transport properties of normal (N) and ferromagnetic (F) atomic-size contacts between superconducting (S) electrodes. This approach is based on non-equilibrium Green function techniques and a Hamiltonian description of the electron transfer processes in the constriction region. For a normal atomic-size contact the theory allows to relate the conduction channels to the atomic orbital structure. In the ferromagnetic case spin polarization gives rise to a spin dependent transmission distribution. For the case of S–N–S constrictions this theory predicts a d.c. current and shot noise in remarkable agreement with recent experimental results. We also analyze S–F and S–F–S constrictions. In this last case the current–voltage characteristic exhibits a very peculiar subgap structure associated to the competition between the multiple Andreev reflection mechanism and the ferromagnetic spin polarization.

An enantiospecific synthesis of a monocyclic core of the antifungal sordarins and sordaricins has been achieved. This synthesis is based on the conversion of (+)-3,9-dibromocamphor into a 1,1,2,2,5-pentasubstituted cyclopentane bearing all the key functionalities present in these antifungals.

A microscopic theory for transport properties of a superconducting quantum point contact is presented. According to contact transmission and quasiparticle damping two different physical regimes can be identified. In the limit of small applied voltages and weak damping this theory provides an exact analytical expression for the current through the contact. The phase-dependent linear conductance thus obtained exhibits an unusual behavior at low temperatures which strongly differs from the standard cos φ -like form. It is argued that a realistic highly transmissive contact will be accurately described by our analytical expression.

Palladium-chelate complexes of the type [PdX2(L-L)] [X = Cl; L-L = 3,3′- (1), 5,5′- (2), or 7,7′-dimethyl-2,2′-biindazole (3) have been prepared, but are too insoluble for structural studies. When X = C6F5 the position of the methyl substituents is critical: thus, 3 is unable to give the corresponding complex due to severe methyl-C6F5 interactions, 2 gives a planar complex, and 1 gives a non-planar (likely helicene-type) complex due to methyl-methyl interaction, as shown by 19F NMR spectroscopy. [Pd(C6F5)X(L-L)][X = Br; L-L = 1] is also non-planar.

The title compound undergoes ring opening under sunlight irradiation to give the bis- 3H -indazole intermediate 15 which adds alcohols to give 1,2-bisindazolyl disubstituted ethanes 16a and 16b .