The industrial chemistry of oils and fats is a mature technology, with decades of experience and refinement behind current practices, therefore some physico-chemical characteristics of eleven vegetable oils sunflower ...The industrial chemistry of oils and fats is a mature technology, with decades of experience and refinement behind current practices, therefore some physico-chemical characteristics of eleven vegetable oils sunflower oil （four different manufacturing companies）, olive oil （three different manufacturing companies）, corn oil, castor oil, coconut oil and canola oil in Iraqi Kurdistan region （Hawler city center） have been evaluated according to association of official analytical chemists （AOAC） （1995） official methods. The refractive index, viscosity, acid value, peroxide value, pH values, and values of specific gravity of the vegetable oil samples were measured at various different conditions. The results showed that some of the oil samples have unacceptable values in comparison with the standards.展开更多
Flax fiber was used to reinforce Polypropylene （PP） owing to its lower impact on environment and suitable mechanical behaviors. To overcome the difficulty of penetrating fibers due to the high viscosity of thermo-pl...Flax fiber was used to reinforce Polypropylene （PP） owing to its lower impact on environment and suitable mechanical behaviors. To overcome the difficulty of penetrating fibers due to the high viscosity of thermo-plastic resin, PP filaments wrapping around the linen yam produced commingled yams, which were woven into fabrics as preforms to make laminates by optimum hot-pressing technology. The effects of fiber volume fraction, fabric density and structure on tensile properties of composites were researched through analyzing the tensile test results and the scanning electronic microscope （SEM） micrographs of fracture surface. Conclusions are drawn that the properties of laminates with fiber volume fraction of 0.50 are better than those with the other two fractions. For plain structure, the tensile properties in warp direction decrease according to the increase of weft density while in weft direction increase. For different fabric structures, properties of laminates with structures of plain 3, twill 2/2 and twill 3/1 increase gradually. And properties in weft direction are prior to those in warp direction for each laminate.展开更多
Formation and preservation of greigite can indicate the physicochemical characteristics of sedimentary environment. Presence of greigite can be diagnosed in the late Pleistocene fluvio-lacustrine sedimentary layers of...Formation and preservation of greigite can indicate the physicochemical characteristics of sedimentary environment. Presence of greigite can be diagnosed in the late Pleistocene fluvio-lacustrine sedimentary layers of 29.4–29.7 and 26.1–27.1 m in core ZK30 of the Yellow River delta, based on analysis of particle size, magnetic properties, scanning electron microscope(SEM) and X-ray diffraction(XRD) measurements. These layers are the transition zones from shallow marine facies to fluvio- lacustrine facies, and from fluvio-lacustrine facies to salt marsh facies in an ascending order, respectively. They are characterized by higher SIRM and SIRM/χ(>30 kA m-1) values than those of other layers, suggesting the possible existence of greigite. Both SEM and XRD analyses confirm its presence. However, sediment layer of 29.4–29.7 m are coarser, and greigite coexists with pyrite, but sediment layer of 26.1–27.1 m are finer and the occurrence of greigite is not accompanied by pyrite. The different occurrence of greigite in the two layers suggests that different climate condition and sedimentary environment control its formation and preservation.展开更多
文摘The industrial chemistry of oils and fats is a mature technology, with decades of experience and refinement behind current practices, therefore some physico-chemical characteristics of eleven vegetable oils sunflower oil （four different manufacturing companies）, olive oil （three different manufacturing companies）, corn oil, castor oil, coconut oil and canola oil in Iraqi Kurdistan region （Hawler city center） have been evaluated according to association of official analytical chemists （AOAC） （1995） official methods. The refractive index, viscosity, acid value, peroxide value, pH values, and values of specific gravity of the vegetable oil samples were measured at various different conditions. The results showed that some of the oil samples have unacceptable values in comparison with the standards.
文摘Flax fiber was used to reinforce Polypropylene （PP） owing to its lower impact on environment and suitable mechanical behaviors. To overcome the difficulty of penetrating fibers due to the high viscosity of thermo-plastic resin, PP filaments wrapping around the linen yam produced commingled yams, which were woven into fabrics as preforms to make laminates by optimum hot-pressing technology. The effects of fiber volume fraction, fabric density and structure on tensile properties of composites were researched through analyzing the tensile test results and the scanning electronic microscope （SEM） micrographs of fracture surface. Conclusions are drawn that the properties of laminates with fiber volume fraction of 0.50 are better than those with the other two fractions. For plain structure, the tensile properties in warp direction decrease according to the increase of weft density while in weft direction increase. For different fabric structures, properties of laminates with structures of plain 3, twill 2/2 and twill 3/1 increase gradually. And properties in weft direction are prior to those in warp direction for each laminate.
基金supported by the National Natural Science Foundation of China(Grant Nos.41030856,41176039,41376054 and 41030856)the Natural Science Foundation of Shandong Province(Grant No.2011ZRE29040)
文摘Formation and preservation of greigite can indicate the physicochemical characteristics of sedimentary environment. Presence of greigite can be diagnosed in the late Pleistocene fluvio-lacustrine sedimentary layers of 29.4–29.7 and 26.1–27.1 m in core ZK30 of the Yellow River delta, based on analysis of particle size, magnetic properties, scanning electron microscope(SEM) and X-ray diffraction(XRD) measurements. These layers are the transition zones from shallow marine facies to fluvio- lacustrine facies, and from fluvio-lacustrine facies to salt marsh facies in an ascending order, respectively. They are characterized by higher SIRM and SIRM/χ(>30 kA m-1) values than those of other layers, suggesting the possible existence of greigite. Both SEM and XRD analyses confirm its presence. However, sediment layer of 29.4–29.7 m are coarser, and greigite coexists with pyrite, but sediment layer of 26.1–27.1 m are finer and the occurrence of greigite is not accompanied by pyrite. The different occurrence of greigite in the two layers suggests that different climate condition and sedimentary environment control its formation and preservation.
