The Aronia melanocarpa El oit was used as test material. The microstruc-ture of normal and vitrified shoots and the characteristics of their stomas on leaf surface were compared by paraffin section and leaf epidermis-...The Aronia melanocarpa El oit was used as test material. The microstruc-ture of normal and vitrified shoots and the characteristics of their stomas on leaf surface were compared by paraffin section and leaf epidermis-tearing method. The results showed the palisade tissue of Aronia melanocarpa El oit consists of 2-3 lay-ers of cells. The stomas on lower epidermis cave in, and are smal and dense. There are abundant vessels and sieve tubes in stems. ln contrast, the main veins of vitrified shoots are unobvious, messy and irregular. The boundary between pal-isade tissue and spongy tissue is not obvious. The stomas open circularly and bigly. The stems are swel ing and thick, but the pith parenchyma cells are broken.展开更多
With the widespread use of polyethylene(PE)materials in gas pipelines,the problem related to the aging of these pipes has attracted increasing attention.Especially under complex environmental conditions involving temp...With the widespread use of polyethylene(PE)materials in gas pipelines,the problem related to the aging of these pipes has attracted increasing attention.Especially under complex environmental conditions involving temperature,humidity,and pressure changes,PE pipes are prone to oxidative degradation,which adversely affects their performance and service life.This study investigates the aging behavior of PE pipes used for gas transport under the combined effects of temperature(ranging from 80℃to 110℃)and pressure(0,0.1,0.2,and 0.3 MPa).By assessing the characteristics and thermal stability of the aged pipes,relevant efforts are provided to explore the performance variations during the aging process and develop methods for evaluating thermal stability.The results indicate that an increase in aging factors,specifically temperature and pressure,significantly reduces theMeltMass Flow Rate(MFR)of polyethylene pipes,suggesting a decline in the material’s flowability during the aging process.Oxidative Induction Time(OIT)tests show that with increasing temperature and pressure,the oxidative induction time of the aged polyethylene pipes progressively shortens,indicating a significant reduction in the material’s oxidative stability.The application of the Arrhenius equation further demonstrates that the aging reaction rate of polyethylene pipes in high-temperature environments is closely related to both temperature and activation energy,thereby laying the foundation of a new approach for the development of an initial model that can reflect the microscopic behavior of polyethylene pipes in aging environments.展开更多
Solvent extraction of palladium （Ⅱ） from hydrochloric acid solution with 2-n-octyl-4-isothiazolin-3-one （OIT）/cyclohexane was studied. Effects of different parameters on extraction efficiency were evaluated. 99.9...Solvent extraction of palladium （Ⅱ） from hydrochloric acid solution with 2-n-octyl-4-isothiazolin-3-one （OIT）/cyclohexane was studied. Effects of different parameters on extraction efficiency were evaluated. 99.96 % and 98.26 % palladium （Ⅱ） could be effectively extracted with 0.018 mol·L^-1 OIT/cyclohexane of 0.1 and 4.0 mol·L^-1 HCl medium, respectively. Nonpolar solvent and low acidity could improve the extracting efficiency, and successfully strip palladium （Ⅱ） from the loaded organic phase was achieved with 0.5 mol·L^-1 （NH2）2CS solution. It was proposed that the extraction of Pd com-plexes from HCl medium proceeded through the ion-association mechanism by slope method, NMR and FF-IR spectra.展开更多
文摘The Aronia melanocarpa El oit was used as test material. The microstruc-ture of normal and vitrified shoots and the characteristics of their stomas on leaf surface were compared by paraffin section and leaf epidermis-tearing method. The results showed the palisade tissue of Aronia melanocarpa El oit consists of 2-3 lay-ers of cells. The stomas on lower epidermis cave in, and are smal and dense. There are abundant vessels and sieve tubes in stems. ln contrast, the main veins of vitrified shoots are unobvious, messy and irregular. The boundary between pal-isade tissue and spongy tissue is not obvious. The stomas open circularly and bigly. The stems are swel ing and thick, but the pith parenchyma cells are broken.
基金supported by the Sponsored by Natural Science Foundation of Xinjiang Uygur Autonomous Region(no.2022D01C389)the Xinjiang University Doctoral Start-up Foundation(no.620321029)the Science and Technology Planning Project of State Administration for Market Regulation(no.2022MK201).
文摘With the widespread use of polyethylene(PE)materials in gas pipelines,the problem related to the aging of these pipes has attracted increasing attention.Especially under complex environmental conditions involving temperature,humidity,and pressure changes,PE pipes are prone to oxidative degradation,which adversely affects their performance and service life.This study investigates the aging behavior of PE pipes used for gas transport under the combined effects of temperature(ranging from 80℃to 110℃)and pressure(0,0.1,0.2,and 0.3 MPa).By assessing the characteristics and thermal stability of the aged pipes,relevant efforts are provided to explore the performance variations during the aging process and develop methods for evaluating thermal stability.The results indicate that an increase in aging factors,specifically temperature and pressure,significantly reduces theMeltMass Flow Rate(MFR)of polyethylene pipes,suggesting a decline in the material’s flowability during the aging process.Oxidative Induction Time(OIT)tests show that with increasing temperature and pressure,the oxidative induction time of the aged polyethylene pipes progressively shortens,indicating a significant reduction in the material’s oxidative stability.The application of the Arrhenius equation further demonstrates that the aging reaction rate of polyethylene pipes in high-temperature environments is closely related to both temperature and activation energy,thereby laying the foundation of a new approach for the development of an initial model that can reflect the microscopic behavior of polyethylene pipes in aging environments.
基金financially supported by the National Natural Science Foundation of China(No.21271073)
文摘Solvent extraction of palladium （Ⅱ） from hydrochloric acid solution with 2-n-octyl-4-isothiazolin-3-one （OIT）/cyclohexane was studied. Effects of different parameters on extraction efficiency were evaluated. 99.96 % and 98.26 % palladium （Ⅱ） could be effectively extracted with 0.018 mol·L^-1 OIT/cyclohexane of 0.1 and 4.0 mol·L^-1 HCl medium, respectively. Nonpolar solvent and low acidity could improve the extracting efficiency, and successfully strip palladium （Ⅱ） from the loaded organic phase was achieved with 0.5 mol·L^-1 （NH2）2CS solution. It was proposed that the extraction of Pd com-plexes from HCl medium proceeded through the ion-association mechanism by slope method, NMR and FF-IR spectra.
