An integrated coal pyrolysis process with iron ore reduction is proposed in this article. As the first step, iron oxide reduction is studied in a fixed bed reactor using simulated coal pyrolysis gas with benzene as a ...An integrated coal pyrolysis process with iron ore reduction is proposed in this article. As the first step, iron oxide reduction is studied in a fixed bed reactor using simulated coal pyrolysis gas with benzene as a model tar compound. Variables such as reduction temperature, reduction time and benzene concentration are studied. The carbon deposition of benzene results in the retarded iron reduction at low temperatures. At high temperatures over800 °C, the presence of benzene in the gas can promote iron reduction. The metallization can reach up to 99% in20 min at 900 °C in the presence of benzene. Significant increases of hydrogen and CO/CO2 ratio are observed in the gas. It is indicated that iron reduction is accompanied by the reforming and decomposition of benzene. The degree of metallization and reduction increases with the increasing benzene concentration. Iron oxide can nearly completely be converted into cementite with benzene present in the gas under the experimental conditions. No sintering is found in the reduced sample with benzene in the gas.展开更多
In this work,uniform reduced graphene oxide(RGO) films were formed on poly-(ethylene terephthalate)(PET) substrates using a simple drop-casting method.We investigated four types of substrates:unmodified PET,pol...In this work,uniform reduced graphene oxide(RGO) films were formed on poly-(ethylene terephthalate)(PET) substrates using a simple drop-casting method.We investigated four types of substrates:unmodified PET,polydopamine-coated PET.carboxyl-group-modified PET,and alkyl-group-modified PET.Upon water evaporation,the surface of the polydopamine-modified PET substrates can interact with the reduced graphene oxide sheets to form flattened and continuous RGO films,which exhibit a sheet resistance of 21.75 kΩ/sq at 82% transmittance.The result indicates that the properties of the surface groups determined whether uniform and flattened RGO films could be formed on the substrates.Hence,we proposed a simple and effective way to produce transparent and conductive films in which the catechol unit exhibits a great effect on the deposition of uniform RGO films on PET substrates.展开更多
The mixing performance of a multi-bladed baffle inserted into a traditional Gallay tote blender is explored by graphic processing unit-based discrete element method software. The mixing patterns and rates are investig...The mixing performance of a multi-bladed baffle inserted into a traditional Gallay tote blender is explored by graphic processing unit-based discrete element method software. The mixing patterns and rates are investigated for a binary mixture, represented by two different colors, under several loading profiles. The baffle effectively enhances the convective mixing both in the axial and radial directions, because of the disturbance it causes to the initial flowing layer and solid-body zone, compared with a blender without a baffle. The axial mixing rate is affected by the gap between the baffle and the wall on the left and right sides, and an optimal blade length corresponds to the maximum mixing rate. However, the radial mixing rate increases with the blade length almost monotonically.展开更多
基金Supported by the joint program of the National Natural Science of Foundation of China and the Shenhua Group Cooperation Limited(51174284)
文摘An integrated coal pyrolysis process with iron ore reduction is proposed in this article. As the first step, iron oxide reduction is studied in a fixed bed reactor using simulated coal pyrolysis gas with benzene as a model tar compound. Variables such as reduction temperature, reduction time and benzene concentration are studied. The carbon deposition of benzene results in the retarded iron reduction at low temperatures. At high temperatures over800 °C, the presence of benzene in the gas can promote iron reduction. The metallization can reach up to 99% in20 min at 900 °C in the presence of benzene. Significant increases of hydrogen and CO/CO2 ratio are observed in the gas. It is indicated that iron reduction is accompanied by the reforming and decomposition of benzene. The degree of metallization and reduction increases with the increasing benzene concentration. Iron oxide can nearly completely be converted into cementite with benzene present in the gas under the experimental conditions. No sintering is found in the reduced sample with benzene in the gas.
基金supported by the National Basic Research Program of China(973 Program)with no.2011CB706900the National Nature Science Foundation of China(nos.50872149 and 50502003)+1 种基金the Scientific Research Foundation for Returned Scholars within the Ministry of Education of Chinathe Presidential Foundation of the Graduate University of the Chinese Academy of Sciences
文摘In this work,uniform reduced graphene oxide(RGO) films were formed on poly-(ethylene terephthalate)(PET) substrates using a simple drop-casting method.We investigated four types of substrates:unmodified PET,polydopamine-coated PET.carboxyl-group-modified PET,and alkyl-group-modified PET.Upon water evaporation,the surface of the polydopamine-modified PET substrates can interact with the reduced graphene oxide sheets to form flattened and continuous RGO films,which exhibit a sheet resistance of 21.75 kΩ/sq at 82% transmittance.The result indicates that the properties of the surface groups determined whether uniform and flattened RGO films could be formed on the substrates.Hence,we proposed a simple and effective way to produce transparent and conductive films in which the catechol unit exhibits a great effect on the deposition of uniform RGO films on PET substrates.
基金This work was supported by the National Key Basic Research Program of China under Grant No. 2015CB251402, the National Natural Science Foundation of China under Grant Nos. 21206167, 21225628, 91434201, and 91334204, the Strategic Priority Research Program of the Chinese Academy of Sciences under Grant No. XDA07080203, and CAS Interdisciplinary Innovation Team.
文摘The mixing performance of a multi-bladed baffle inserted into a traditional Gallay tote blender is explored by graphic processing unit-based discrete element method software. The mixing patterns and rates are investigated for a binary mixture, represented by two different colors, under several loading profiles. The baffle effectively enhances the convective mixing both in the axial and radial directions, because of the disturbance it causes to the initial flowing layer and solid-body zone, compared with a blender without a baffle. The axial mixing rate is affected by the gap between the baffle and the wall on the left and right sides, and an optimal blade length corresponds to the maximum mixing rate. However, the radial mixing rate increases with the blade length almost monotonically.