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1.
Extraction of plant materials is an essential practice in various fields using natural compounds. Nevertheless, it is challenging to perform complicated extraction efficiently and consistently on materials with hard-to-crush structures. This work presents a new method called simultaneous stone-milling and extraction (SME) to achieve one-step extraction of hard materials. SME under its optimal conditions was confirmed to produce high quality extracts from whole spice seeds (anise seeds, dill seeds, fennel seeds) and coarse-cut star anise. Compared to other extraction methods like maceration, heat-assisted extraction and ultrasound-assisted extraction, SME extracts contained comparable or higher concentrations of general (polyphenols, flavonoids, antioxidants) and specific (enzyme inhibitors) bioactive groups. Hence, SME with its one-step operation is expected to simplify the task of plant extraction and contribute to the advances in studies using plant-derived phytochemicals.  相似文献   
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In this paper, apple crispness was evaluated by sensory evaluation and compared with non-destructive measurements of portable acoustic signal to discuss the feasibility of non-destructive evaluation for apple crispness based on portable acoustic signal. Acoustic eigenvalues from the acoustic signal were processed by time domain and Hilbert–Huang transform (HHT), followed by analysing the correlations with apple crispness that had been evaluated via sensory evaluation. Multiple linear regression (MLR) and artificial neural network (ANN) were applied to predict apple crispness. The results proved that crispness correlates significantly (P < 0.01) with four acoustic eigenvalues, including waveform index, sound intensity, energy of low frequency and energy of high frequency. The average relative error of apple crispness predicted by ANN was 1.42 ± 1.9%, remarkably lower (P < 0.01) that of MLR (6.79 ± 5.64%), implying that the model predicted by ANN is more accurate than that of MLR.  相似文献   
4.
The world market for functional foods has grown dynamically and China is expected to be one of the most promising markets. But little is understood the formation mechanisms of consumers’ purchase attitude and intention toward functional foods in Mainland China. The current study investigates the roles of trust, health consciousness and price in shaping consumers’ purchase intention toward functional foods by focusing on purchase attitude as a mediator and food neophobia as a moderator. Results from the sample of 1144 Chinese suggest that Chinese consumers had moderate purchase intention toward functional foods. Trust in the food system and health consciousness positively affects purchase intention via purchase attitude. Price negatively affects purchase intention; meanwhile, the negative effect could be counteracted by health consciousness. Food neophobia does not directly affect individuals’ purchase attitude or intention, but moderates the relationships between antecedents and them. Consumers with a low level of food neophobia treat higher price as a monetary sacrifice, while their counterparts may regard a higher price as a greater quality signal. The study offers the food industry insights into the development and marketing of functional foods targeted to the Mainland China market.  相似文献   
5.
The influence of microwave boiling (MB treated 5, 10 and 15 s was abbreviated as MB5, MB10 and MB15, respectively) and high-pressure boiling (HB processed 10, 20 and 30 min was denoted as HB10, HB20 and HB30, respectively) processing on the composition and content of bound phenolic substances of sorghum hull and their antioxidant capacity were evaluated. Nine bound phenolic profiles were identified by HPLC-ESI-MS/MS, including syringic acid, veratric acid, p-hydroxybenzonic acid, caffeic acid, sinapic alcohol, ascorbic acid, prenylnaringenin and luteolin. Compared with traditional hot water processing (HP treated 10, 30 and 50 min was abbreviated as HP10, HP30 and HP50, respectively), the content of free procyanidins and total phenolics of sorghum hull treated with HB increased by 35.92–58.87% and 6.20–18.70%, respectively. Sorghum hull treated with HB20 possessed the highest ABTS (ABTS radical scavenging capacity) and FRAP (ferric ion reducing antioxidant power) among all treatment groups.  相似文献   
6.
Six novel photoluminescent Ln–Cu(I) heterobimetallic 3D coordination polymers, [LnCu (pyip2 )2(H2O)]n (16) (where Ln is Pr, Nd, Sm, Eu, Gd, Ho, respectively, and H2pyip = 5-(4-pyridyl) isophthalic acid) have been synthesized in a concise and reproducible manner under hydrothermal conditions. All of these substances were fully characterized by appropriate spectroscopic methods and elemental analysis. Structural determinations revealed that 16 are isomorphic and display 3D frameworks. Luminescent properties of the obtained compounds have been studied in detail revealing light emissions of warm white, cool white and light blue for 3, 4 and 5, respectively. The effectiveness of association of a rare earth with a transition metal in producing valuable luminescent materials for practical applications is demonstrated.  相似文献   
7.
Segmentation is crucial for targeting product development initiatives and marketing communication nationally as well as internationally. In this paper we use the Food Related Lifestyle instrument that has been applied in the food arena for many years as a ‘stepping stone’ to develop a contemporary, targeted and smaller version of the Food Related Lifestyle instrument, still following the original theoretical framework. In particular we focus on three dimensions that have proven to be of core value in segmentation: food involvement; food innovativeness; and, food responsibility. Based on data collection in six countries (DK, AU, HU, UK, USA and NZ) across two rounds from 2017 to 2019 (total N = 3396), we propose a new core instrument consisting of 15 items that have been tested for cross-cultural validity. Next, we used these three dimensions for segmentation across the six countries by applying multi-level latent class analysis. A solution leading to five different segments could be identified; the foodies, the moderates, the adventurous, the uninvolved and the conservatives. The segments were profiled by means of Schwartz’s ten value domains and measures of self-reported food-related behaviour to check for nomonological validity. We conclude that the 15 items were cross-culturally valid, could be used for segmentation across six countries, and that segment profiling by means of Schwartz values and behavioural items were in line with the theoretical background.  相似文献   
8.
Optomagnetic multifunctional composite based on upconversion luminescence nanomaterial is regarded as a promising strategy for bioimaging,disease diagnosis and targeted delivery of drugs.To explore a mesoporous nanostructure with excellent water dispersibility and high drug-loading capacity,a novel nanorattle-structured Fe3O4@SiO2@NaYF4∶Yb,Er magnetic upconversion nanorattle (MUCNR) was suc-cessfully designed by using Fe3O4 as core and NaYF4∶Yb,Er nanocrystals as shell.The microstructures and crystal phase of the as-prepared MUCNRs were evaluated by transmission electron microscopy,X-ray powder diffraction and N2 adsorption/desorption isotherms.The Kirkendall effect was adapted to explain the formation mechanism of the MUCNRs.The loading content and encapsulation efficiency of doxorubicin hydrochloride (DOX) could reach as high as 18.2% and 60.7%,respectively.Moreover,the DOX loading MUCNR (DOX-MUCNR) system showed excellent sustained drug release and strong pH-dependent performance,which was conducive to drug release at the slightly acidic microenvironment of tumor.Microcalorimetry was used to quantify the interactions between the carrier structure and drug release rate directly.The heat release rates in the heat-flow diagrams are basically consistent with the DOX release rate,thereby showing that microcalorimetry assay not only provides a unique thermody-namic explanation for the structure-activity relationship of Fe3O4@SiO2@NaYF4∶Yb,Er MUCNRs but also provides powerful guidance to avoid the blind selection or design of drug carriers.Therefore,our work firmly provided a comprehensive perspective for using Fe3O4@SiO2@NaYF4∶Yb,Er MUCNRs as a remark-able magnetic targeted drug carrier.  相似文献   
9.
Nanoemulsion-based acai oil was obtained by the phase inversion method using two nonionic surfactants, Ceteareth-20 (Brij™ CS20) and polyoxyethylene-hydrogenated castor oil (Croduret™ 50), with the concentration of each surfactant varying from 7 to 10 %. The formulation with 10 % Brij CS20 presented the best values for droplet size, zeta potential, and polydispersity index (PDI). Ketoconazole was incorporated into this formulation, with an encapsulation efficiency of 98.31 % and equally good zeta potential, droplet size, and PDI, and spherical shape when observed by transmission electron microscopy. Overall, nanoemulsions of acai oil proved to be a good vehicle for imidazole antifungals such as ketoconazole.  相似文献   
10.
Ni-based catalysts have been widely studied in reforming methane with carbon dioxide. However, Ni-based catalysts tends to form carbon deposition at low temperatures (≤600 °C), compared with high temperatures. In this paper, a series of Ni/SiO2-XG catalysts were prepared by the glycine-assisted incipient wetness impregnation method, in which X means the molar ratio of glycine to nitrate. XRD, H2-TPR, TEM and XPS results confirmed that the addition of glycine can increase Ni dispersion and enhance the metal-support interaction. When X ≥ 0.3, these catalysts have strong metal-support interaction and small Ni particle size. The Ni/SiO2-0.7G catalyst has the best catalytic performance in dry reforming of methane (DRM) test at 600 °C, and its CH4 conversion is 3.7 times that of Ni/SiO2-0G catalyst. After 20 h reaction under high GHSV (6 × 105 ml/gcat/h), the carbon deposition of Ni/SiO2-0.7G catalyst is obviously lower than that of Ni/SiO2-0G catalyst. Glycine-assisted impregnation method can enhance the metal-support interaction and decrease the metal particle size,which is a method to prepare highly dispersed and stable Ni-based catalyst.  相似文献   
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