Cold-pressed oils from six herb plant seeds and four woody plant seeds were analyzed and compared for their quality characteristics such as oil, crud protein, shell, and moisture content, fatty acid （FA） compositio...Cold-pressed oils from six herb plant seeds and four woody plant seeds were analyzed and compared for their quality characteristics such as oil, crud protein, shell, and moisture content, fatty acid （FA） compositions and oxidation stability. Results showed that walnut kernel contained the greatest amount of seed oil and safflower seed contained the lowest. Safflower, pumpkin, hemp, camellia and peony seeds had high shell content, their kernel oil content significantly increased after shelling. These oils had significant differences （p〈0.01） in levels of fatty acids and the ratio of n-6：n-3 fatty acids. Camellia, safflower, and flax seed oil contained the highest oleic acid, linoleic acid, and a-linolenic acid respectively. Hemp seed oil was observed in a 3.53：1 ratio of n-6 and n-3 fatty acids. All these ten oils were obviously different in moisture and volatile content, acid value, peroxide value and induction period （IP） （p〈0.01）. IP of peony seed oil was lowest （0.94 h） and almond oil was the highest （14.10 h）. IP of oils negatively correlated with polyunsaturated fatty acids content ^=-0.664, p=0.036）. These studies of ten cold-pressed oils may provide better explanation for their potential health benefits and further developing their commercial value.展开更多
Ten cold-pressed oil from 6 herb plant seeds （sesame, fax, saffower, pumpkin, tomato and hemp） and 4 woody plant seeds （camellia, almond, walnut and peony） were analyzed to determine bioactive compounds content, i...Ten cold-pressed oil from 6 herb plant seeds （sesame, fax, saffower, pumpkin, tomato and hemp） and 4 woody plant seeds （camellia, almond, walnut and peony） were analyzed to determine bioactive compounds content, including tocopherols, phytosterols and phenolics, as well as their antioxidant activities. Total tocopherols content ranged from 161.11 mg/kg in camellia seed oil to 1,072.51 mg/kg in tomato seed oil. Tomato seed oil had the highest total phytosterols （708.89 mg/100 g） and phenolics content （20.27 mg SAE/100 g）,whereas, saffower seed oil has the lowest total phytosterols （173.75 mg/100g） and walnut kernel oil contained the lowest phenolics （2.32 mg SAE/100 g）, respectively. Tomato seed oil exhibited the strongest ferric-reducing antioxidant power （FARP, 311.36 μmol/100 g） and 2,2-diphenyl-1-picrylhydrazyl （DPPH） radical scavenging activity （56.40 μmol/100 g）, while camellia seed oil had the lowest FRAP value （34.83 μmol/100 g） and fax seed oil had the lowest DPPH value （2.75 μmol/100 g）. Correlation coeffcient was determined as 0.647 and 0.863 between FRAP value and total tocopherols and phenolics, and 0.673 and 0.711 between DPPH value and total tocopherols and phenolics （p 〈 0.05）, respectively. This result indicated the antioxidant activities （FRAP and DPPH） were highly correlated with total tocopherols and phenolics content of oil. This study will be very useful for comprehensive utilization of all 10 cold-press oils.展开更多
Click-clack噪声是双离合器变速器(DCT)特有的NVH问题,通常发生在低挡位、低车速Tip In/Out工况。以某6速DCT Tip In/Out工况Click-clack噪声为例,详细阐述了DCT Click-clack噪声产生的机制,通过扭振测试及变速器标定的方法,消除或改善C...Click-clack噪声是双离合器变速器(DCT)特有的NVH问题,通常发生在低挡位、低车速Tip In/Out工况。以某6速DCT Tip In/Out工况Click-clack噪声为例,详细阐述了DCT Click-clack噪声产生的机制,通过扭振测试及变速器标定的方法,消除或改善Click-clack噪声。展开更多
Two special rare earth elements cerium and europium were chosen to conduct chemical modification of the BaTiO3 structure. The cold-pressing ceramic processing technique was used to prepare barium titanate ceramics dop...Two special rare earth elements cerium and europium were chosen to conduct chemical modification of the BaTiO3 structure. The cold-pressing ceramic processing technique was used to prepare barium titanate ceramics doped with Ce at Ti sites and with Eu at Ba sites on the base of formulas Ba （ Ti1 -x Cex ） O3 （x = 0. 05, 0. 10 ） （CBT） and （ Ba1-y Euy ） Ti1-x/8O3 （ y = 0. 05, 0. 10） （EBT）. Associated with structures and microstructures, the effects of cerium and europium doping on dielectric properties of BaTiO3 ceramics were discussed. The CBT ceramics exhibit a pseudocubic perovskite structure, while the EBT ceramics exhibit a tetragonal perovskite structure with the exception of the existence of a small percentage of the Eu2Ti2O7 phase. The Curie peak of BaTiO3 shifts towards room temperature at rates of 3 ℃/mol Ce atoms and 10 ℃/mol Eu atoms（ Eu≤5% ）, respectively. Compared with the CBT ceramics, the EBT ceramics show significant advantages, such as a narrow fine grain size distribution（ 1 μm）, a lower porosity and a higher density（5.85 g/cm^3）, more stable dielectric-temperature dependence（ ε′= 1600-1800 at t 〈 50℃ ） and a lower dissipation factor（ 〈 0. 05 ）. The stability of dielectric constant with frequency in BaTiO3 can extend to 107 Hz due to Ce and Eu doping.展开更多
文摘Cold-pressed oils from six herb plant seeds and four woody plant seeds were analyzed and compared for their quality characteristics such as oil, crud protein, shell, and moisture content, fatty acid （FA） compositions and oxidation stability. Results showed that walnut kernel contained the greatest amount of seed oil and safflower seed contained the lowest. Safflower, pumpkin, hemp, camellia and peony seeds had high shell content, their kernel oil content significantly increased after shelling. These oils had significant differences （p〈0.01） in levels of fatty acids and the ratio of n-6：n-3 fatty acids. Camellia, safflower, and flax seed oil contained the highest oleic acid, linoleic acid, and a-linolenic acid respectively. Hemp seed oil was observed in a 3.53：1 ratio of n-6 and n-3 fatty acids. All these ten oils were obviously different in moisture and volatile content, acid value, peroxide value and induction period （IP） （p〈0.01）. IP of peony seed oil was lowest （0.94 h） and almond oil was the highest （14.10 h）. IP of oils negatively correlated with polyunsaturated fatty acids content ^=-0.664, p=0.036）. These studies of ten cold-pressed oils may provide better explanation for their potential health benefits and further developing their commercial value.
基金National Key R&D Program of China(2017YFD0400402)National Natural Science Foundation of China(31471620)National Science Foundation of China(31772010)for financial support
文摘Ten cold-pressed oil from 6 herb plant seeds （sesame, fax, saffower, pumpkin, tomato and hemp） and 4 woody plant seeds （camellia, almond, walnut and peony） were analyzed to determine bioactive compounds content, including tocopherols, phytosterols and phenolics, as well as their antioxidant activities. Total tocopherols content ranged from 161.11 mg/kg in camellia seed oil to 1,072.51 mg/kg in tomato seed oil. Tomato seed oil had the highest total phytosterols （708.89 mg/100 g） and phenolics content （20.27 mg SAE/100 g）,whereas, saffower seed oil has the lowest total phytosterols （173.75 mg/100g） and walnut kernel oil contained the lowest phenolics （2.32 mg SAE/100 g）, respectively. Tomato seed oil exhibited the strongest ferric-reducing antioxidant power （FARP, 311.36 μmol/100 g） and 2,2-diphenyl-1-picrylhydrazyl （DPPH） radical scavenging activity （56.40 μmol/100 g）, while camellia seed oil had the lowest FRAP value （34.83 μmol/100 g） and fax seed oil had the lowest DPPH value （2.75 μmol/100 g）. Correlation coeffcient was determined as 0.647 and 0.863 between FRAP value and total tocopherols and phenolics, and 0.673 and 0.711 between DPPH value and total tocopherols and phenolics （p 〈 0.05）, respectively. This result indicated the antioxidant activities （FRAP and DPPH） were highly correlated with total tocopherols and phenolics content of oil. This study will be very useful for comprehensive utilization of all 10 cold-press oils.
文摘Click-clack噪声是双离合器变速器(DCT)特有的NVH问题,通常发生在低挡位、低车速Tip In/Out工况。以某6速DCT Tip In/Out工况Click-clack噪声为例,详细阐述了DCT Click-clack噪声产生的机制,通过扭振测试及变速器标定的方法,消除或改善Click-clack噪声。
基金Supported by Fukumori International Patent Co., Ltd.(No. 407053)
文摘Two special rare earth elements cerium and europium were chosen to conduct chemical modification of the BaTiO3 structure. The cold-pressing ceramic processing technique was used to prepare barium titanate ceramics doped with Ce at Ti sites and with Eu at Ba sites on the base of formulas Ba （ Ti1 -x Cex ） O3 （x = 0. 05, 0. 10 ） （CBT） and （ Ba1-y Euy ） Ti1-x/8O3 （ y = 0. 05, 0. 10） （EBT）. Associated with structures and microstructures, the effects of cerium and europium doping on dielectric properties of BaTiO3 ceramics were discussed. The CBT ceramics exhibit a pseudocubic perovskite structure, while the EBT ceramics exhibit a tetragonal perovskite structure with the exception of the existence of a small percentage of the Eu2Ti2O7 phase. The Curie peak of BaTiO3 shifts towards room temperature at rates of 3 ℃/mol Ce atoms and 10 ℃/mol Eu atoms（ Eu≤5% ）, respectively. Compared with the CBT ceramics, the EBT ceramics show significant advantages, such as a narrow fine grain size distribution（ 1 μm）, a lower porosity and a higher density（5.85 g/cm^3）, more stable dielectric-temperature dependence（ ε′= 1600-1800 at t 〈 50℃ ） and a lower dissipation factor（ 〈 0. 05 ）. The stability of dielectric constant with frequency in BaTiO3 can extend to 107 Hz due to Ce and Eu doping.
