An accurate and objective assessment of the health status of EMU trains is of great importance.In order to make sure the trains are functional,reliable,and endurable in their full life cycle(FLC),health assessment met...An accurate and objective assessment of the health status of EMU trains is of great importance.In order to make sure the trains are functional,reliable,and endurable in their full life cycle(FLC),health assessment method for EMU trains after Level 3-5 maintenance and repair is studied.First,the element-selection principles and the assessment rules are defined;second,to present the complex topological relationship between the elements in assessment,a functional logical structure construction method is proposed;third,a health value calculation model is defined based on the element’s characteristics and their logical structures.The health variables of each element is calculated and fitted following the steps in the corresponding weight calculation methods.The assessment method is proved to be applicable and effective.展开更多
A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly conce...A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly concentrated in the 2CaO SiO2-3CaO P2O5 solid solution,the recovery of P from dephosphorization slag primarily depends on the separation of the solid solution from other phases.The distribution ratios of P2O5 between solid solution and liquid phase in the CaOSiO2-FeO-P2O5-Nslag system were investigated.The results indicated that the addition of Na2O facilitated the enrichment of P2O5 in the solid solution because it increased not only the distribution ratio of P2O5 but also the mass fraction of the solid solution.The distribution ratio of P2O5 was independent of the P2O5 content in slag.A higher P2O5 content in slag resulted in higher P2O5 and Na2O contents in the solid solution.The distribution ratio of P2O5 increased with the total Fe content in the liquid phase,regardless of the valence of Fe.An increase in the FeO content in slag brought a higher P2O5 content in the solid solution.As slag basicity increased,the distribution ratio of P2O5 increased,but the P2O5 content in the solid solution decreased.展开更多
Long-term and synchronous monitoring of PMIo and PM2.s was conducted in Chengdu in China from 2007 to 2013. The levels, variations, compositions and size distributions were investigated. The sources were quantified by...Long-term and synchronous monitoring of PMIo and PM2.s was conducted in Chengdu in China from 2007 to 2013. The levels, variations, compositions and size distributions were investigated. The sources were quantified by two-way and three-way receptor models (PMF2, ME2-2way and ME2-3way), Consistent results were found: the primary source categories contributed 63.4% (PMF2), 64.8% (ME2-2way) and 66.8% (ME2-Bway) to PMIo, and contributed 60.9% (PMF2), 65.5% (ME2-2way) and 61.0% (ME2-3way) to PM2.s. Secondary sources contributed 31.8% (PMF2), 32.9% (ME2-2way) and 31.7% (ME2-3way) to PMIo, and 35.0% (PMF2), 33.8% (ME2-2way) and 36.0% (ME2-3way) to PM2.s. The size distribution of source categories was estimated better by the ME2-3way method. The three-way model can simultaneously consider chemical species, temporal variability and PM sizes, while a two-way model independently computes datasets of different sizes. A method called source directional apportionment (SDA) was employed to quantify the contributions from various directions for each source category. Crustal dust from east-north-east (ENE) contributed the highest to both PM^o (12.7%) and PMzs (9.7%) in Chengdu, followed by the crustal dust from south-east (SE) for PMao (9.8%) and secondary nitrate & secondary organic carbon from ENE for PMzs (9.6%). Source contributions from different directions are associated with meteorological conditions, source locations and emission patterns during the sampling period. These findings and methods provide useful tools to better understand PM pollution status and tn dovolon offoctive nolhltion control gtrateMeg.展开更多
BACKGROUND Only a few cases of giant pseudomeningoceles have been reported in the literature.Herein,we report a giant pseudomeningocele of the cervical spine that was found after cervical laminectomy for an epidural h...BACKGROUND Only a few cases of giant pseudomeningoceles have been reported in the literature.Herein,we report a giant pseudomeningocele of the cervical spine that was found after cervical laminectomy for an epidural hematoma following epidural blockade.CASE SUMMARY A 47-year-old man presented with recurrent neck pain and posterior neck swelling after spinal surgery.Magnetic resonance imaging of the cervical spine revealed fluid collection(5.6 cm×6.6 cm×11.2 cm)at the C3-6 level;this proved to be a pseudomeningocele.Symptoms related to the pseudomeningocele resolved following dural repair and fat graft transplantation.CONCLUSION Although rare,pseudomeningocele is a possibility in patients with recurrent back pain,radicular pain,or a persistent headache following spinal surgery.Continuous attention should be paid throughout the spinal procedure,whether conservative or non-conservative.展开更多
文摘An accurate and objective assessment of the health status of EMU trains is of great importance.In order to make sure the trains are functional,reliable,and endurable in their full life cycle(FLC),health assessment method for EMU trains after Level 3-5 maintenance and repair is studied.First,the element-selection principles and the assessment rules are defined;second,to present the complex topological relationship between the elements in assessment,a functional logical structure construction method is proposed;third,a health value calculation model is defined based on the element’s characteristics and their logical structures.The health variables of each element is calculated and fitted following the steps in the corresponding weight calculation methods.The assessment method is proved to be applicable and effective.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.51704010,51604003,U1760117)Key Laboratory Open Project Fund of Metallurgical Emission Reduction and Resources Recycling(Anhui University of Technology)Ministry of Education(JKF18-02).
文摘A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly concentrated in the 2CaO SiO2-3CaO P2O5 solid solution,the recovery of P from dephosphorization slag primarily depends on the separation of the solid solution from other phases.The distribution ratios of P2O5 between solid solution and liquid phase in the CaOSiO2-FeO-P2O5-Nslag system were investigated.The results indicated that the addition of Na2O facilitated the enrichment of P2O5 in the solid solution because it increased not only the distribution ratio of P2O5 but also the mass fraction of the solid solution.The distribution ratio of P2O5 was independent of the P2O5 content in slag.A higher P2O5 content in slag resulted in higher P2O5 and Na2O contents in the solid solution.The distribution ratio of P2O5 increased with the total Fe content in the liquid phase,regardless of the valence of Fe.An increase in the FeO content in slag brought a higher P2O5 content in the solid solution.As slag basicity increased,the distribution ratio of P2O5 increased,but the P2O5 content in the solid solution decreased.
基金supported by the Tianjin Natural Science Foundation(No.16JCQNJC08700)the Fundamental Research Funds for the Central Universities+4 种基金National Key Research and Development Program of China(No.2016YFC0208500)the National Natural Science Foundation of China(No.21407174)the Tianjin Research Program of Application Foundation(No.14JCQNJC08100)the Tianjin Science and Technology Project(Nos.16YFZCSF00260,14ZCDGSF00027,14ZCDGSF00029)the Special Funds for Research on Public Welfares of the Ministry of Environmental Protection of China(201309072)
文摘Long-term and synchronous monitoring of PMIo and PM2.s was conducted in Chengdu in China from 2007 to 2013. The levels, variations, compositions and size distributions were investigated. The sources were quantified by two-way and three-way receptor models (PMF2, ME2-2way and ME2-3way), Consistent results were found: the primary source categories contributed 63.4% (PMF2), 64.8% (ME2-2way) and 66.8% (ME2-Bway) to PMIo, and contributed 60.9% (PMF2), 65.5% (ME2-2way) and 61.0% (ME2-3way) to PM2.s. Secondary sources contributed 31.8% (PMF2), 32.9% (ME2-2way) and 31.7% (ME2-3way) to PMIo, and 35.0% (PMF2), 33.8% (ME2-2way) and 36.0% (ME2-3way) to PM2.s. The size distribution of source categories was estimated better by the ME2-3way method. The three-way model can simultaneously consider chemical species, temporal variability and PM sizes, while a two-way model independently computes datasets of different sizes. A method called source directional apportionment (SDA) was employed to quantify the contributions from various directions for each source category. Crustal dust from east-north-east (ENE) contributed the highest to both PM^o (12.7%) and PMzs (9.7%) in Chengdu, followed by the crustal dust from south-east (SE) for PMao (9.8%) and secondary nitrate & secondary organic carbon from ENE for PMzs (9.6%). Source contributions from different directions are associated with meteorological conditions, source locations and emission patterns during the sampling period. These findings and methods provide useful tools to better understand PM pollution status and tn dovolon offoctive nolhltion control gtrateMeg.
文摘BACKGROUND Only a few cases of giant pseudomeningoceles have been reported in the literature.Herein,we report a giant pseudomeningocele of the cervical spine that was found after cervical laminectomy for an epidural hematoma following epidural blockade.CASE SUMMARY A 47-year-old man presented with recurrent neck pain and posterior neck swelling after spinal surgery.Magnetic resonance imaging of the cervical spine revealed fluid collection(5.6 cm×6.6 cm×11.2 cm)at the C3-6 level;this proved to be a pseudomeningocele.Symptoms related to the pseudomeningocele resolved following dural repair and fat graft transplantation.CONCLUSION Although rare,pseudomeningocele is a possibility in patients with recurrent back pain,radicular pain,or a persistent headache following spinal surgery.Continuous attention should be paid throughout the spinal procedure,whether conservative or non-conservative.