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Lu F.,Chongqing University | Wen L.-Y.,Chongqing University | Wang H.-P.,Chongqing University | Liang H.-L.,Chongqing University | Li Y.-K.,Institute of Multipurpose Utilization of Mineral Resources
Guocheng Gongcheng Xuebao/The Chinese Journal of Process Engineering | Year: 2015

The interaction between gas and particles in a fluidized furnace was simulated using CFD software. The distribution of instantaneous particles concentration, change of velocity and orientation of particles with time, pressure drop with height at the center of bed, and radial concentration distribution of particles under various arc degrees of furnace bottom were investigated. The results showed that the gas from the center of flat bottom was stronger than that from the arc bottom, when the superficial velocity was 0.24 m/s. The center pressure dropped suddenly at the height of 300~400 mm, the inner loop in the region of reaction was reinforced, and the particles concentration was distributed equally when the arc degree of bottom was 60°, the portion of bubbles with the diameter less than 50 mm was higher and the number of bubbles was more than that under the arc degrees of 90° and 0°. The simulated results agreed with the experimental ones of photographs and parameter change curves of gas-particles flow. A better fluidization could be achieved under the arc degree of furnace bottom at 60°. ©, 2015, Science Press. All right reserved.

Lu Y.,University of Sichuan | Lu Y.,Institute of Multipurpose Utilization of Mineral Resources | Wang J.,University of Sichuan | Yuan H.,University of Sichuan | Xiao D.,University of Sichuan
Analytical Methods | Year: 2014

Carbon quantum dots (CQDs) have attracted significant attention due to their low toxicity, biocompatibility and potential applications, particularly in the field of biomedical imaging. However, the major drawback limiting the application of CQDs is their relatively low quantum yield (QY). For further study and applications of CQDs, this class of carbon nanomaterials requires separation and purification. In this paper, we report a general method to separate CQDs obtained using resorcinol (m-C6H6O2) as the carbon precursor on a C18 column through high performance liquid chromatography (HPLC). The separation of CQDs was achieved by binary gradient elution using acetonitrile-water and acetonitrile-methanol as the mobile phases and acetonitrile plays an important role in the separation of CQDs. The resolution of some peaks improved when the flow rate was increased; however, the separation of certain other peaks worsened, almost disappearing at higher flow rates. The characterization of the collected fractions revealed that the oxygen-containing functional groups on the CQDs are crucial when separating the CQDs through this method. Our method is feasible and the collected purified CQDs have QY as high as 0.72. © the Partner Organisations 2014.

Xu S.,Chongqing University | Long M.,Chongqing University | Li Y.,Institute of Multipurpose Utilization of Mineral Resources | Chen D.,Chongqing University | And 3 more authors.
Metalurgia International | Year: 2013

The extraction of vanadium from a high Ca/V ratio vanadium was studied by direct roasting and water leaching. In the present paper, the effects of Na2CO3 amount, roasting temperature and roasting time on the extraction of vanadium were studied. Results showed that the Na2CO3 amount and roasting temperature are the main factors in roasting process affecting the final leaching rate of vanadium. As indicated in the experimental study, the optimal Na2CO3 amount is 19%, the roasting temperature is 800°C, and the roasting time is 90 min respectively. By the mean of TG-DSC analysis and X-Ray diffraction(XRD) techniques, the oxidation process and material phase transformation of vanadium slag during roasting process under the optimal roasting conditions were analyzed and discussed.

Fei G.-C.,Chengdu University of Technology | Wen C.-Q.,Chengdu University of Technology | Zhou X.,Chengdu University of Technology | Zhou X.,Institute of Multipurpose Utilization of Mineral Resources | And 2 more authors.
Kuangwu Yanshi/ Journal of Mineralogy and Petrology | Year: 2010

Dongzhongla ore deposit is located in the Zhaxue-Yaguila mineralization area, Nyainqentanglha Range, Tibet and is a new founded middle-large size lead-zinc deposit. The host quartz veins in the Dongzhong lead-zinc deposit was measured by laser microprobe 40Ar-39Ar dating method in order to obtain the ore-forming age. As a result, the isochron age of the ore is 42. 2 Ma ±1. 7 Ma, inverse isochron age is 42 Ma±3 Ma with the MSWD value of 2. 4 and the initial 40Ar/36 Ar value of 303. 6±1.4. The measured age is in agreement with-the inverse isochron age within a reasonable error range, and the dating results can be regarded as the ore-forming age of the Dongzhong lead-zinc deposit (formed during early Eocene). In the same mineralization zone, the Sharang porphyry molybdenum deposit has a Re-Os isochrone age of 51 Ma ±1.0 Ma,and the Yaguila lead-zinc-molybdenum polymetallic deposit yields a Re-Os weighted average model age of 58.7 Ma ±8. 5 Ma. All the geochronology information indicated that the mineralization movements occurred during main Indian-Asian collision period (41 Ma∼65 Ma) in the Nyainqentanglha mineralization belt. This study provided important evidence for the research and exploration of lead-zinc molybdenum-copper polymetallic ore deposits in the Nyainqentanglha Range.

Fei G.-C.,Chengdu University of Technology | Wen C.-Q.,Chengdu University of Technology | Wang C.-S.,Bureau of Mineral Resources | Zhou X.,Chengdu University of Technology | And 4 more authors.
Geology in China | Year: 2010

Located in the Zhaxue -Yaguila metallogenic belt of the Nyainqentanglha Range, Tibet, the Dongzhongla ore deposit is a newly-discovered lead-zinc polymetallic deposit. The exposed porphyry granite has an intimate relationship with the Dongzhongla ore deposit. In order to determine the accurate age of the porphyry granite in Dongzhongla, the authors employed the zircon SHRIMP U-Pb isotope dating technology and obtained the age of 124.4 ±1.9 Ma (MSWD =5.09), indicating Cretaceous. This age is essentially in agreement with the event of magmatism in the east of the Gangdise -Nyainqentanglha volcanic -magmatic belt (from 109 Ma to 130 Ma) and the age of granites in the Zhaxue-Jinda lead-zinc polymetallic metallogenic belt. Combined with regional data, it is suggested that the Dongzhongla early Cretaceous porphyry granites resulted from the crustal thickening melting of the intra -arc rift tensional system. This age provides the important evidence for Cretaceous magmatism and helps to direct studies related to lead -zinc molybdenum -copper polymetallic ore exploration in the Nyainqentanglha Range.

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