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Identification of odor compounds in fresh sea buckthorn juice (FSBJ) and pulp (SBP) was performed by gas chromatography-mass spectrometry-olfactometry (GC-MS-O). A total of 39 and 36 odor compounds were identified in FSBJ and SBP, respectively. Further findings revealed that ethyl hexanoate, ethyl 2-methylbutyrate, ethyl 3-methylbutyrate, and 3-methylbutyl 3-methylbutanoate had high flavor dilution (FD) factors and were identified as the key odor compounds in FSBJ. In addition, the contents of ester compounds contributing to the fruity odor were significantly reduced in SBP after pasteurization. Sensory evaluation and electronic tongue analysis revealed that the sweetness and overall taste of SBP were superior to those of FSBJ. The contents of vitamin C and total flavonoids were significantly lower in SBP than in FSBJ, indicating that pasteurization reduces the nutritional quality of FSBJ. The results of the study can provide theoretical references for the flavor and nutritional quality optimization of sea buckthorn products.

ZnO varistors are widely employed for overvoltage protections and surge absorptions due to their excellent nonlinear current–voltage characteristics originating from double Schottky barriers (DSBs). In most cases, they are operating under moderate ac voltages, while calculating the transient current responses of DSBs remains a challenge, impeding the development of condition assessments. In this paper, a transient conducting model for the DSB is proposed by quantifying the charge trapping processes of the interface states. The DSB is found to quickly reach a quasi-steady state, where the interfacial charge stabilizes with only small modulations at a relatively high level above the dc equilibrium value, even though the applied ac voltage varies in time and polarity. This is the result of efficient charge trapping and slow de-trapping by grain boundary interface states. For charge compensation under the time-varying voltage, the width of the two depletion regions of the DSB shows periodic changes. The proposed model is validated by a satisfying agreement between experimentally measured current responses and simulation results of ZnO varistors. The findings of this study provide a perspective on investigating the time-varying conducting systems and open avenues for condition assessments of nonlinear conducting devices. [ABSTRACT FROM AUTHOR]

The co-achieving of stable colossal permittivity (CP) and low dielectric loss in dielectric materials has been a challenge. In this paper, a transition in CP was observed in V-doped CaCu3Ti4O12 (CCTO) ceramics. The fast high-frequency dielectric relaxation that mainly contributed to CP of CCTO ceramics was greatly suppressed in V-doped CCTO samples. Its relaxation activation energy remained ∼0.10 eV, while its magnitude dropped from thousands in CCTO to dozens in V-doped CCTO. Instead, CP of V-doped CCTO ceramics mainly arose from another slow dielectric relaxation, which appeared in a much lower frequency range. Moreover, this dielectric relaxation gradually turned from a "carrier-dominated" relaxation into a "dipole-dominated" one with the increase in temperature. Its relaxation activation energy also changed from ∼0.06 to 0.42 eV in the meanwhile. These results indicated important roles of multiple point defects and their relating charge transport in CP behaviors. It supported that CP arose from electron trapping behaviors at the edge of double Schottky barriers at grain boundaries. On this basis, suppression of any deep-level point defects was concluded to be a potential clue to achieve both stable CP and sufficiently low dielectric loss in CCTO ceramics and other CP materials. [ABSTRACT FROM AUTHOR]