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Lanzou Alkaline Stretched Noodles (LASN) was a traditional staple food in northwest China for nearly 90 years. LASN specialty wheat breeding has become an important target since 1990s. In order to discover the LASN specialty wheat quality requirement for allelic variations at Glu-3 of northwest China spring wheats. Two northwest China spring wheat cultivars and 39 elite F6 breeding lines were adopted to determine the low-molecular-weight glutenin subunits (LMW-GS) composition by one step one-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) basing on the protocol of Singh et al. (1991). The results showed that Glu-A3d and Glu-B3g were correlated to high protein content, high volume of SDS-sediment and super dough strength (W). While Glu-A3a was bad to dry gluten content and SDS-sediment as well as dough properties such as dough strength (W) and dough tenacity (P). Moreover, Glu-B3j has not significant influence on flour quality, but it has the negative effect on dough strength (W) and dough extensibility (L). As for LASN quality, Glu-A3d and Glu-B3g were beneficial alleles and Glu-A3a was unbeneficial alleles for LASN quality.

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The purpose of this study was to evaluate the ability of Lactobacillus rhamnosus to bind patulin (PAT) in the buffer solution and apple juice. The binding of L. rhamnosus to PAT was reversible, which improved the stability of the bacterial complex. The ability to bind PAT can be enhanced with the inactivation of the strain by high temperature and acid treatment. Acid-treated bacteria had the highest PAT binding rate of 72.73±1.05%. The binding rates of acid and high temperature (121 °C) treatments were increased by 21.37% and 19.15%, respectively. L. rhamnosus showed the best detoxification ability to PAT at 37 °C, where the binding rate reached 50.9±1.03%. When the dose of inactivated bacteria powder was 0.02 g ml−1, the minimum concentration of PAT in apple juice was 0.37 µg ml−1. The addition of the L. rhamnosus inactivated powder did not affect the quality of the juice product and effectively bound the PAT in apple juice.

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The present study was to evaluate the survival rate of free and encapsulated Bifidobacterium bifidum BB28 under simulated gastrointestinal conditions and its stability during storage. Results showed that non-microencapsulated Bifidobacterium bifidum BB28 was more susceptible to simulated gastrointestinal conditions than microencapsulated bacteria. Microencapsulated Bifidobacterium BB28 exhibited a lower population reduction than free cells during exposure to simulated gastrointestinal conditions, the viable count of monolayer microcapsules, double layer microcapsules, and triple layer microcapsules decreased by nine magnitudes, four magnitudes, and one magnitude after 2 h, respectively. The enteric test showed that the microorganism cells were released from the monolayer, double layer, and triple layer microcapsules completely in 40 min. Moreover, the optimum storage times of free Bifidobacterium BB28, monolayer microcapsules, double layer microcapsules, and triple layer microcapsules were 21 days, 21 days, 28 days, and more than 35 days in orange juice, pure milk, and nutrition Express (a commercially available milk based drink), and the viable counts were maintained at 1×106 CFU g−1 or more, which means that the double layer and triple layer of microcapsules of B. bifidum BB28 have great potential in food application.

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Abstract

The decomposition process of barium, cerium and neodymium oxalates in air was investigated by DTA-TG. Decomposition of an oxalate coprecipitate precursor and formation of barium cerate were examined in air, N2 and CO2 atmospheres, respectively, by employing DTA-TG and XRD. The results showed that, in air, cerium oxalate could easily be decomposed to CeO2 below 350°C and Nd2O3 could be obtained at 670°C, while a high temperature of >1400°C was needed to obtain BaO. Although some amount of BaCeO3 was formed at 500°C in air, at 650°C in N2 and at 800°C in CO2, single perovskite phase of BaCeO3 could only be obtained at a much higher temperature.

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Abstract  

The catalytic and accelerating effects of three coal-burning additives (CBA) on the burning of graphite were studied with the help of thermogravimetric (TG) analysis. The kinetic study on the catalytic oxidation of the graphite doped with CBA was carried out and the results were presented. The results show that the CBA can change the carbon oxidation/combustion course by catalytic action and change the activation energy, thus improving the combustion efficiency.

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Abstract  

Highly oriented single crystal antimony nanowire arrays have been synthesized within anodic aluminum oxide (AAO) template by pulsed electrodeposition. Thermal behavior and oxidation analysis of the antimony nanowires have been investigated by means of thermogravimetry and differential scanning calorimetry in Ar and air atmosphere, respectively. Compared to bulk antimony, the antimony nanowires exhibit a lower sublimation temperature at 496.4°C. Evident oxidation of the Sb nanowires occurs at 429.8°C in air atmosphere and α-Sb2O4 nanowires have been obtained as the oxidation product. The results indicate that the sublimation and the oxidation of the antimony nanowires in the AAO template is a slow multi-step process. The present results are of relevance when processing antimony nanowries for thermoelectric applications at high temperatures.

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Abstract  

Fe–B ultrafine amorphous alloy particles (UFAAP) were prepared by chemical reduction of Fe3+ with NaBHO4 and confirmed to be ultrafine amorphous particles by transmission electron microscopy and X-ray diffraction. The specific heat of the sample was measured by a high precision adiabatic calorimeter, and a differential scanning calorimeter was used for thermal stability analysis. A topological structure of Fe-B atoms is proposed to explain two crystallization peaks and a melting peak observed at T=600, 868 and 1645 K, respectively.

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Acta Alimentaria
Authors:
C.Y. Zhou
,
Q.W. Cheng
,
T. Chen
,
L.L. Meng
,
T.G. Sun
,
B. Hu
,
J. Yang
, and
D.Y. Zhang

Abstract

To study the feasibility of evaluating the quality characteristics of banana based on the browning area. The texture characteristics, total soluble solids (TSS), ascorbic acid, malondialdehyde (MDA) concentrations, relative conductivity, polyphenol oxidase, peroxidase, and phenylalanine ammonia-lyase (PAL) activities in banana peels were detected during storage. A linear model was made by principal component analysis and multiple linear regression between the banana browning area and characteristic indices. The results showed that the changes in the physiological characteristics of bananas were significantly different during different storage periods. The main factors that affected the banana browning area were relative conductivity, PAL, TSS, and MDA, indicating that lipid peroxidation, respiration, and metabolism of phenylpropanoids had significant influence on the banana browning area during storage. Thus, it is feasible to predict banana quality based on changes in browning area, which could be a rapid and non-destructive detection of banana quality during storage.

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Journal of Thermal Analysis and Calorimetry
Authors:
F. Xu
,
L. Sun
,
J. Zhang
,
Y. Qi
,
L. Yang
,
H. Ru
,
C. Wang
,
X. Meng
,
X. Lan
,
Q. Jiao
, and
F. Huang

Abstract  

Heat capacities of the carbon nanotubes (CNTs) with different sizes have been measured by modulated temperature differential scanning calorimetry (MDSC) and reported for the first time. The results indicated the values of C p increased with shortening length of CNTs when the diameters of CNTs were between 60 and 100 nm. However, the values of C p of CNTs were not affected by their diameter when the lengths of CNTs were 1–2 um, or not affected by the length of CNTs when their diameters were below 10 nm. The thermal stabilities of the CNTs have been studied by TG-DTG-DSC. The results of TG-DTG showed that thermal stabilities of CNTs were enhanced with their diameters increase. With lengths increase, the thermal stabilities of CNTs increased when their diameters were between 60 and 100 nm, but there is a slight decrease when their diameters were less than 60 nm. The further DSC analyses showed both released heat and T onset increased with the increase of CNTs diameters, which confirms the consistency of the results from both TG-DTG and DSC on CNTs thermal stability.

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Summary

A selective and sensitive liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) method was developed and validated for analysis of xanthotoxol (1), xanthotoxin (2), isoimpinellin (3), bergapten (4), oxypeucedanin (5), imperatorin (6), cnidilin (7), and isoimperatorin (8) in rat bile and urine using pimpinellin as an internal standard (IS). An Agilent 1200 liquid chromatography system (Agilent Technologies, USA) equipped with a quaternary pump, an autosampler, and a column compartment was used for all analyses. Chromatographic separations were performed on a Sapphire C18 column (150 mm × 4.6 mm, 5 μm), and the column temperature was maintained at 30°C; the sample injection volume was 10 μL. The specificity, linearity, accuracy, precision, recovery, matrix effect, and several stabilities were validated for all analytes in the rat bile and urine samples. The method was successfully applied in monitoring the concentrations of eight coumarins in rat bile and urine after a single oral administration of Radix Angelicae Dahuricae extract with a dosage of 8.0 mL/kg. In the bile samples, the eight coumarins excreted completely in twenty-four hours. The average percentages of coumarins (1–8) excreted were 0.045%, 0.019%, 0.177%, 0.105%, 0.337%, 0.023%, 0.024%, 0.021%. In the urine samples, the eight coumarins excreted completely in seventy-two hours. The average percentages of coumarins (1–8) excreted were 1.78%, 0.095%, 0.130%, 0.292%, 0.082%, 0.008%, 0.005%, 0.004%. The method is robust and specific and it can successfully complete the requirements of the excretion study of the eight coumarins in Radix Angelicae Dahuricae.

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