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9篇 您的检索式:作者名="Congren"
    题名 作者 年代 出处 被引量
1Utilization of polysaccharides as depressants for the flotation separation of copper/lead concentrate显示文摘The interaction mechanism between dextrin and minerals has been investigated through micro-flotation, adsorption density measurements, Fourier transform infrared ray (FTIR) spectroscopic studies and dissolution tests. Dextrin shows a good depressing action towards galena but not chalcopyrite. FTIR spectroscopic studies indicate that dextrin chemically adsorbed on galena surface in alkaline pH range. Dissolution tests confirm leaching action of metal ions from chalcopyrite and galena surfaces, and dextrin-lead ion interaction. Adsorption measurements present that the higher adsorption density of O-isopropyl-N-ethyl thionocarbamate (IPETC) onto chalcopyrite than that onto galena, and IPETC adsorbed on galena decrease with increasing dextrin concentrations in the presence of dextrin, attesting the flotation results.Qin Wenqing Wei Qian Jiao Fen Yang Congren Liu Ruizeng Wang Peipei Ke Lifang 2013International Journal of Mining Science and Technology2013,23,2:16
2Floral characteristics and pollination ecology of Manglietia ventii(Magnoliaceae),a plant species with extremely small populations(PSESP)endemic to South Yunnan of China显示文摘Manglietia ventii is a highly endangered plant species endemic to Yunnan province in China, where there are only five known small populations. Despite abundant flowering there is very low fruit and seed set,and very few seedlings in natural populations, indicating problems with reproduction. The causes of low fecundity in M. ventii are not known, largely because of insufficient knowledge of the species pollination ecology and breeding system. We conducted observations and pollination experiments, and analyzed floral scents to understand the pollinatoreplant interactions and the role of floral scent in this relationship, as well as the species breeding system. Like the majority of Magnoliaceae, M. ventii has protogynous and nocturnal flowers that emit a strong fragrance over two consecutive evenings. There is a closing period(the pre-staminate stage) during the process of anthesis of a flower, and we characterize the key flowering process as an 'open-close-reopen' flowering rhythm with five distinct floral stages observed throughout the floral period of this species: pre-pistillate, pistillate, pre-staminate, staminate,and post-staminate. Flowers are in the pistillate stage during the first night of anthesis and enter the staminate stage the next night. During anthesis, floral scent emission occurs in the pistillate and staminate stages. The effective pollinators were weevils(Sitophilus sp.) and beetles(Anomala sp.), while the role of Rove beetles(Aleochara sp.) and thrips(Thrips sp.) in pollination of M. ventii appears to be minor or absent. The major chemical compounds of the floral scents were Limonene, b-Pinene, a-Pinene, 1,8-Cineole, Methyl-2-methylbutyrate, p-Cymene, Methyl-3-methyl-2-butenoate and 2-Methoxy-2-methyl-3-buten, and the relative proportions of these compounds varied between the pistillate and staminate stages. Production of these chemicals coincided with flower visitation by weevils and beetles.The results of pollination experiments suggest that M. ventii is pollinator-dependent, and low seed set in natural populations is a result of insufficient pollen deposition. Thus, conservation of the species should focus on improving pollination service through the introduction of genetically variable individuals and increase in density of reproducing trees.Bin Wang Gao Chen Congren Li Weibang Sun 2017Plant Diversity2017,39,1:8
3A novel approach to with a preparing ultra-lightweight ceramsite large amount of fly ash显示文摘The disposal of fly ash has become a serious problem in China due to its rapid increase in volume in recent years.The most common method of fly ash disposal is solidification-stabilization-landfill,and the most common reuse is low-value-added building materials.A novel processing method for preparing ultra-lightweight ceramsite with fly ash was developed.The results show that the optimal parameters for preparation of ultra-lightweight ceramsite are as follows:mass ratio of fly ash:kaolin:diatomite=80:15:5,preheating temperature of 800℃,preheating time of 5 min,sintering temperatiire of 1220℃,and sintering time of 10 min.The expansion agent is perlite,at 10 wt.% addition.Finally,a ceramsite with bulk density of 340 kg/m3,particle density of 0.68 g/cm3,and cylinder compressive strength of 1.02 MPa was obtained.Because of its low density and high porosity,ultra-lightweight ceramsite has excellent thermal insulation performance,and its strength is generally low,so it is usually used in the production of thermal insulation concrete and its products.The formation of a liquid-phase component on the surface,and generation of a gas phase inside ceramsite during the sintering process,make it possible to control the production of the suitable liquid phase and gas in this system,resulting in an optimization of the expansion behavior and microstructure of ceramsite.These characteristics show the feasibility of industrial applications of fly ash for the production of ultralightweight ceramsite,which could not only produce economic benefits,but also conserve land resources and protect the environment.Sen Liu Congren Yang Wei Liu Longsheng Yi Wenqing Qin 2020Frontiers of Environmental Science & Engineering2020,14,4:2
4Investigation of condition-induced bubble size and distribution in electroflotation using a high-speed camera显示文摘In the flotation process,bubble is a key factor in studying bubble-particle interaction and fine particle flotation.Knowledge on size distribution of bubbles in a flotation system is highly important.In this study,bubble distributions in different reagent concentrations,electrolyte concentrations,cathode apertures,and current densities in electroflotation are determined using a high-speed camera.Average bubble sizes under different conditions are calculated using Image-ProòPlus(Media Cyberneticsò,MD,USA)and SigmaScanòPro(Systat Software,CA,USA)software.Results indicate that the average sizes of bubbles,which were generated through 38,50,74,150,250,420,and 1000 lm cathode apertures,are 20.2,29.5,44.6,59.2,68.7,78.5,and 88.8 lm,respectively.The optimal current density in electroflotation is20 A/m2.Reagent and electrolyte concentrations,current density,and cathode aperture are important factors in controlling bubble size and nucleation.These factors also contribute to the control of fineparticle flotation.Ren Liuyi Zhang Yimin Qin Wenqing Bao Shenxu Wang Peipei Yang Congren 2014International Journal of Mining Science and Technology2014,24,1:2
5Bioleaching of a low grade nickel-copper-cobalt sulfide ore 显示文摘Yang Congren Qin Wenqing Lai Shaoshi 2011Hydrometallurgy2011,106,12:1
6Bioleaching of chalcopyrite by moderately thermophilic microorganisms显示文摘Wenqing Qin Congren Yang Shaoshi Lai Jun Wang Kai Liu Bo Zhang 2013Bioresource Technology2013,,:1
7Application of EDTMPS as a novel calcite depressant in scheelite flotation显示文摘In this study, the innovative use of ethylenediamine tetramethylene phosphonic sodium(EDTMPS) as a calcite depressant in scheelite flotation was investigated by flotation experiments, and its selective depression mechanism was revealed by contact angle measurement, FTIR analysis, Zeta potential test and XPS analysis. The flotation experiment results showed that scheelite and calcite could be efficiently separated under the following conditions: pulp p H=9.5, Na OL concentration of 1.5×10^(-4)mol/L, EDTMPS concentration of 3.0×10^(-5)mol/L, a scheelite concentrate with WO3grade of 65.49%, recovery of 83.29%and separation efficiency of 65.29% could be obtained from the artificially mixed minerals. The analysis results of mineral surface properties demonstrated that EDTMPS was strongly adsorbed onto the calcite surface through the reaction between the phosphonate group and the calcium ions, which hindered Na OL adsorption and increased the hydrophilicity of calcite. However, EDTMPS had weak adsorption strength on the scheelite surface, which didn’t affect further adsorption of Na OL, hence, the scheelite remained hydrophobic. Consequently, the selective adsorption of EDTMPS on the two minerals’ surfaces increased a difference in wettability and thus enabling them to be separated by flotation. Finally, the mechanism model of this flotation separation process was established.Fen Jiao Wei Li Xu Wang Congren Yang Zhengquan Zhang Liwen Fu Wenqing Qin 2023International Journal of Mining Science and Technology2023,33,5:1
8Alkyl dimethyl betaine activates the low-temperature collection capacity of sodium oleate for scheelite显示文摘The impact of alkyl dimethyl betaine (ADB) on the collection capacity of sodium oleate (NaOl) at low temperatures was evaluated using flotation tests at various scales. The low-temperature synergistic mechanism of ADB and NaOl was explored by infrared spectroscopy, X-ray photoelectron spectroscopy, surface tension measurement, foam performance test, and flotation reagent size measurement.The flotation tests revealed that the collector mixed with octadecyl dimethyl betaine (ODB) and NaOl in a mass ratio of 4:96 exhibited the highest collection capacity. The combined collector could increase the scheelite recovery by 3.48% at low temperatures of 8–12℃. This is particularly relevant in the Luanchuan area, which has the largest scheelite concentrate output in China. The results confirmed that ODB enhanced the collection capability of NaOl by improving the dispersion and foaming performance. Betaine can be introduced as an additive to NaOl to improve the recovery of scheelite at low temperatures.Xu Wang Zhengquan Zhang Yanfang Cui Wei Li Congren Yang Hao Song Wenqing Qin Fen Jiao 2024International Journal of Minerals,Metallurgy and Materials2024,31,1:0
9Uncovering the evolution of tin use in the United States and its implications显示文摘Tin is of key importance to daily life and national security;it is considered an essential industrial metal.The United States(US)is the world’s largest economy and consumer of natural resources.Therefore,the analysis of historical tin use in the US is helpful for understanding future tin use trends in the world as a whole and in developing countries.Time series analysis,regression analysis with GDP or GDP/capita,and historical data fitted with logistic and Gompertz models are employed in this study.Historical tin use in the US shows three stages-increase-constant-decrease,as GDP per capita has increased.Tin use in the US is negatively correlated with the GDP value added by the manufacturing sector,while the use of tin worldwide and in China continues to increase along with the GDP value added by the manufacturing sector.Although a sigmoid curve can fit the US tin use data well,that use is not directly related to the limited tin reserves or resources.Rather,policies,economic restructuring,substitutions,new end-use markets,etc.have played key roles in the changing tin use patterns.This work contributes to understanding future tin use at both the global and national levels:tin use will continue to increase with GDP at the global level,but use patterns of tin at the national level can be changed through human intervention.Congren Yang Xianlai Zeng Haodong Li Zuyuan Tian Wei Liu Wenqing Qin Jinhui Li 2021Frontiers of Environmental Science & Engineering2021,15,6:0
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