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清代浮尸收瘗中的人文关怀 被引量:2
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作者 蓝勇 张铭 《学术研究》 CSSCI 北大核心 2018年第2期117-125,共9页
清代浮尸多能得到较为妥善的收瘗,很少出现"挟尸要价"、"挟尸索费"的现象。具体的收瘗过程中有大量细致入微的人性化举措,如强调浮尸打捞时分"击见即捞"和"看明再捞"区别对待,待殓时需要搭建... 清代浮尸多能得到较为妥善的收瘗,很少出现"挟尸要价"、"挟尸索费"的现象。具体的收瘗过程中有大量细致入微的人性化举措,如强调浮尸打捞时分"击见即捞"和"看明再捞"区别对待,待殓时需要搭建尸棚尸场以避免暴露,相验时务尽详明,停厝待认时想方设法寻觅尸亲。埋葬时多须二次收瘗,坟茔形制及埋葬用度等须务得如式,并注明浮尸信息以备尸亲查寻,时时培护墓冢,浮尸随身财物分公私两条路径妥善处理,务使归亲。埋葬后须坚持岁时祭祀并照顾尸亲,始终坚持"不问阶层、众生平等"的浮尸处理原则。虽然清代在浮尸收瘗具体实践过程中,实际的收瘗效果与完善的制度规定之间存在一定的差异,但总体而言,清代整个浮尸收瘗过程中具体收瘗细节处处体现出无微不至的人文关怀,实现了"死者免暴露",值得当下借鉴。 展开更多
关键词 清代 人文关怀
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清末九江地方厘务人员薪酬水平与厘金浮收关系研究 被引量:3
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作者 孙健 《中国经济史研究》 CSSCI 北大核心 2019年第5期76-90,共15页
清末有关厘金的论述,多以厘卡局员贪墨,浮收之数难以在各省向户部提交的清册中体现。本文依据清末海关九江的厘金报告,分析九江各卡局员官方薪酬相对粮价的水平。分析结果显示,九江厘金局卡员役勒索私征,从制度上与其薪金报酬偏低有关;... 清末有关厘金的论述,多以厘卡局员贪墨,浮收之数难以在各省向户部提交的清册中体现。本文依据清末海关九江的厘金报告,分析九江各卡局员官方薪酬相对粮价的水平。分析结果显示,九江厘金局卡员役勒索私征,从制度上与其薪金报酬偏低有关;厘金的实际税率普遍达到15.14%—24.03%,甚至一度超出30%。浮收占实征数目的比重,保守估计为10.22%—27.87%。若放宽标准,则这一数字计入米厘的结果可能达到20%以上;若仅以百货厘金为计算标准,则浮收接近半数;若以浮收接近半数反推厘务人员收入,则其实际收入可能是制度收入的五到十倍;与此对应,厘金的实际税率则会进一步提升。 展开更多
关键词 九江 厘务人员 薪酬 厘金浮收
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清代浮收案件的论罪和启示
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作者 付宁馨 《法律适用》 CSSCI 北大核心 2018年第18期112-120,共9页
浮收案件是清代刑案中的重要部分。税收关系到国家命脉,也是中国古代州县官的重要职责。清代社会构成更加复杂,治吏成为统治者亟需解决的问题。清代浮收案件反映了胥吏诈赃等问题的司法判断,涉及的法律分布在吏律、户律、刑律三门,涵盖... 浮收案件是清代刑案中的重要部分。税收关系到国家命脉,也是中国古代州县官的重要职责。清代社会构成更加复杂,治吏成为统治者亟需解决的问题。清代浮收案件反映了胥吏诈赃等问题的司法判断,涉及的法律分布在吏律、户律、刑律三门,涵盖行政违法、贪污、受贿等部门,是"官-吏-民"纠纷的重要体现。通过清代浮收案件,我们可以进一步理解古代社会官吏关系和吏民关系,并由此对现代中国基层行政发包制、职务犯罪等有所启发。 展开更多
关键词 浮收 蠹役诈赃 吏治 受贿罪
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定额财政、税收瓶颈与治理失范——传统国家治理质量的财政视角 被引量:1
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作者 谢红星 《华中科技大学学报(社会科学版)》 CSSCI 北大核心 2020年第3期112-121,共10页
由于缺乏必要的财产认证制度及技术手段,传统国家很难全面掌握经济运行及纳税人财产状况的真实信息,以及从千变万化的经济信息和纳税人财产变动信息中准确确定税收的合理额度与基准,由此,其税收不得不以建立在相对稳定的土地收成之上的... 由于缺乏必要的财产认证制度及技术手段,传统国家很难全面掌握经济运行及纳税人财产状况的真实信息,以及从千变万化的经济信息和纳税人财产变动信息中准确确定税收的合理额度与基准,由此,其税收不得不以建立在相对稳定的土地收成之上的田赋为主,并带有某种"定额财政"的特点。国家税收很难随着经济的成长而同步增加,尤其是很难从工商业创造的巨额财富中开辟稳定可期的税源。大一统中央集权帝国的建立意味着政府所承担的公共职能大规模扩张,国家财政支出由此极为浩大,难以减省,且随着王朝法制的逐渐败坏呈不可逆转的恶性膨胀趋势。为了解决收支之间的缺口,传统国家在"强干弱枝"的名义下,持续挤压和割夺地方财政,从而加剧了本已存在的地方经费之紧缺;地方官府为满足其俸给和经费的需求,不得不在正税之外浮收加征、摊捐杂派,并愈加愈多,反过来又影响国家正税之征收,最终百姓穷、国家亦穷,"藏富于民"变成了"藏富于官""藏富于豪强",国家与百姓双输。 展开更多
关键词 能力 定额财政 强干弱枝 浮收加征
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直吸式收盐机研发 被引量:2
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作者 纪天龙 张庆龙 +1 位作者 马海永 周革 《盐业与化工》 CAS 2016年第8期37-38,共2页
针对浮吸式收盐机二级输盐电机对盐的破损严重、形成粉盐多、集盐耙拆卸不方便、扒盐过程中形成盐绺不均的现况,研制适合的直吸式收盐机。
关键词 吸式盐机 直吸式盐机 结晶
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清末银钱比价波动与地方官府赋税征解(1901-1911) 被引量:2
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作者 蒋立场 《安徽史学》 CSSCI 北大核心 2007年第1期42-46,共5页
清末十余年间,在国内外种种因素交互作用下,银钱比价波动具有阶段性特征与区域性特征。受银钱比价波动阶段性的影响,地方各级官府的赋税征解经历了一个由征钱解银到征银解银发展演变的过程。地方各级官府在赋税征收中私自采取的种种抑... 清末十余年间,在国内外种种因素交互作用下,银钱比价波动具有阶段性特征与区域性特征。受银钱比价波动阶段性的影响,地方各级官府的赋税征解经历了一个由征钱解银到征银解银发展演变的过程。地方各级官府在赋税征收中私自采取的种种抑勒浮收行径,是造成银钱比价波动具有区域性特征的不可或缺的因素。地方官府财政税收行为与货币金融市场之间构成一种复杂的恶性互动关系。这种恶性互动关系的进一步发展演变,则导致清末币制更趋紊乱,吏治更加腐败,国家财政日益困窘,商贸运营严重受阻,民生愈益艰难,从而大大加剧清政府统治的危机。 展开更多
关键词 清末 银钱比价波动 赋税征解 抑勒浮收
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论胡林翼在湖北的减赋改革 被引量:1
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作者 甘迎春 《怀化学院学报》 2006年第10期82-84,共3页
胡林翼在署理湖北巡抚期间(1855-1861),针对湖北衙门冗杂重叠,征收浮收过多,农民负担沉重,政府财政收支困难的局面,进行了一次大的减赋改革。这次改革主要在三个方面展开:减免农民的田赋和浮收、整顿厘金和漕务、减免捐输的数额,改革取... 胡林翼在署理湖北巡抚期间(1855-1861),针对湖北衙门冗杂重叠,征收浮收过多,农民负担沉重,政府财政收支困难的局面,进行了一次大的减赋改革。这次改革主要在三个方面展开:减免农民的田赋和浮收、整顿厘金和漕务、减免捐输的数额,改革取得了一定的成绩,但由于国内外的战争环境,急需大量的赋税收入,最终改革在1861年被迫停止。 展开更多
关键词 胡林翼 减赋 浮收 厘金 漕务 捐输
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Flotation separation of Xixia andalusite ore 被引量:3
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作者 周灵初 张一敏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第6期1388-1394,共7页
The flotation behavior of Xixia andalusite was studied with different collectors.The tests were conducted with a pure andalusite sample in micro-flotation cell and then with an ore sample in a mechanical flotation cel... The flotation behavior of Xixia andalusite was studied with different collectors.The tests were conducted with a pure andalusite sample in micro-flotation cell and then with an ore sample in a mechanical flotation cell.The surface charge was measured on pure andalusite sample and the isoelectric point(IEP) was found to be pH 5.2.Andalusite is floated with an amine collector above IEP where mineral surface is negatively charged.In contrast,an alkyl sulfonate collector(sodium dodecyl benzene sulfonate) is effective in the pH range where andalusite surface is positively charged.Furthermore,andalusite is floated with oleate in neutral and mildly alkaline pH values.55.3% Al2O3 is produced with 75.6% andalusite recovery when using the alkyl benzene sulfonate collector.Starch is found to be an effective depressant for gangue minerals in alkyl benzene sulfonate flotation.Moreover,slimes are found to have an adverse effect on the flotation of andalusite.Therefore,pretreatment by desliming and pre-float(to remove carbonaceous species) prior to andalusite flotation is necessary. 展开更多
关键词 ANDALUSITE FLOTATION collectors DESLIMING pre-float isoelectric point(IEP)
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清代浮尸收瘗保障制度研究 被引量:1
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作者 张铭 蓝勇 《历史教学(下半月)》 CSSCI 北大核心 2018年第3期56-63,共8页
当下民间浮尸收瘗因存在诸多问题,动辄"挟尸索费",造成了不良的社会影响,然清代处理收瘗事宜则较为顺畅,既有相应的规章制度保障,避免了各种棍徒的敲诈勒索,又有来自官方和民间的资金支持,保障了所需经费用度,同时从报信、打... 当下民间浮尸收瘗因存在诸多问题,动辄"挟尸索费",造成了不良的社会影响,然清代处理收瘗事宜则较为顺畅,既有相应的规章制度保障,避免了各种棍徒的敲诈勒索,又有来自官方和民间的资金支持,保障了所需经费用度,同时从报信、打捞到埋葬等具体环节给予了人员相应酬劳,为收瘗工作提供了持续的人力支持。清代较为完备的保障制度使浮尸收瘗事业得以完全公益性。参考清代浮尸收瘗保障制度,可为当下各类公益保障措施的制定提供一定的借鉴意义。 展开更多
关键词 清代 制度 保障
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Flotation of low-grade bauxite using organosilicon cationic collector and starch depressant 被引量:7
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作者 余新阳 王浩林 +2 位作者 王强强 冯博 钟宏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第4期1112-1117,共6页
The flotation of diaspore and three kinds of silicate minerals, including kaolinite, illite and pyrophyllite, using an organosilicon cationic surfactant (TAS101) as collector and starch as depressant was investigated.... The flotation of diaspore and three kinds of silicate minerals, including kaolinite, illite and pyrophyllite, using an organosilicon cationic surfactant (TAS101) as collector and starch as depressant was investigated. The results show that both diaspore and aluminosilicate minerals float readily with organosilicon cationic collector TAS101 at pH values of 4 to 10. Starch has a strong depression effect for diaspore in the alkaline pH region but has little influence on the flotation of aluminosilicate minerals. It is possible to separate diaspore from aluminosilicate minerals using the organosilicon cationic collector and starch depressant. Further studies of bauxite ore flotation were also conducted, and the reverse flotation separation process was adopted. The concentrates with the mass ratio of Al2O3 to SiO2 of 9.58 and Al2O3 recovery of 83.34% are obtained from natural bauxite ore with the mass ratio of Al2O3 to SiO2 of 6.1 at pH value of 11 using the organosilicon cationic collector and starch depressant. 展开更多
关键词 BAUXITE reverse flotation organosilicon cationic collector starch depressant
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Separation behavior and mechanism of hematite and collophane in the presence of collector RFP-138 被引量:1
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作者 余侃萍 余永富 许向阳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期501-507,共7页
The reverse flotation separation performance and mechanism of hematite and cellophane in the presence of RFP-138, a newly synthesized dephosphorization collector, were studied. Reverse flotation tests on monominerals ... The reverse flotation separation performance and mechanism of hematite and cellophane in the presence of RFP-138, a newly synthesized dephosphorization collector, were studied. Reverse flotation tests on monominerals and artificially mixed minerals of hematite and collophanite show that, this anionic collector performs excellently in reducing the phosphorus content in hematite. It can decrease the content of P in artificially mixed minerals from 1.05% to 0.12% and achieve the TFe recovery rate of 91.30%. The chemical behavior of solution and infrared spectra of RFP-138 were investigated to explore the selective collecting mechanism of RFP-138 to these two minerals. 展开更多
关键词 HEMATITE collophane reverse flotation separation DEPHOSPHORIZATION dephosphorization collector
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Investigating the first-order flotation kinetics models for Sarcheshmeh copper sulfide ore 被引量:12
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作者 Asghar Azizi Ahmad Hassanzadeh Behnam Fadaei 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第5期849-854,共6页
This study was performed in two phases of work.In the first stage,four conventional first-order flotation kinetics models were fitted to the measured recoveries data and the best model were selected.In the second stag... This study was performed in two phases of work.In the first stage,four conventional first-order flotation kinetics models were fitted to the measured recoveries data and the best model were selected.In the second stage,influence of pH,solid concentration,water chemistry and the amount of collector dosage were investigated on kinetics parameters including flotation rate constant and ultimate recovery.The results indicated that that perfectly mixed reactor model and Kelsall model gave the best and the weakest fit to the experimental data,respectively.It was observed that flotation rate constant and ultimate recovery were strongly affected by chemical factors investigated especially water quality.The flotation rate constant decreased with increasing the solids content,while ultimate recovery increased to certain value and thereafter reduced.It was also found that the most values of flotation rate constant and ultimate recovery obtained in dosage of collector are 30 and 40 g/t,respectively. 展开更多
关键词 Copper ore FLOTATION Kinetics model Rate constant Ultimate recovery
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Flotation performance and adsorption mechanism of novel 1-(2-hydroxyphenyl)hex-2-en-1-one oxime flotation collector to malachite 被引量:16
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作者 Fang-xu LI Xiao-tong ZHOU Ri-xiao LIN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第10期2792-2801,共10页
A novel collector 1-(2-hydroxyphenyl)hex-2-en-1-one oxime(HPHO)was synthesized from 2-hydroxy acetophenone and butyraldehyde.Its flotation performance and adsorption mechanism to malachite were investigated by flotati... A novel collector 1-(2-hydroxyphenyl)hex-2-en-1-one oxime(HPHO)was synthesized from 2-hydroxy acetophenone and butyraldehyde.Its flotation performance and adsorption mechanism to malachite were investigated by flotation test,zeta potential,Fourier transform infrared(FTIR)and X-ray photoelectron spectroscopy(XPS)analysis techniques.Compared with benzohydroxamic acid(BA),1-(2-hydroxyphenyl)ethan-1-one oxime(HPEO)and sodium isobutyl xanthate(SIBX),HPHO exhibited excellent collecting power to malachite without additional reagents,such as Na2S regulator and methyl isobutyl carbinol(MIBC)frother.Results of zeta potential indicated that HPHO was coated on malachite surfaces through a chemisorption process.FTIR and XPS data gave clear evidence for the formation of Cu−oxime complex on malachite surfaces after HPHO adsorption through the linkage between C=C,—OH,N—OH group and Cu species. 展开更多
关键词 MALACHITE FLOTATION COLLECTOR OXIME adsorption mechanism
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A novel collector RL for flotation of bauxite 被引量:19
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作者 卢毅屏 张国范 +1 位作者 冯其明 欧乐明 《Journal of Central South University of Technology》 2002年第1期21-24,共4页
The flotation properties of single minerals such as diaspore, kaolinite and pyrophllite in bauxites were investigated using RL as collector. The effects of regulators and unavoidable ions on flotation were studied. Ba... The flotation properties of single minerals such as diaspore, kaolinite and pyrophllite in bauxites were investigated using RL as collector. The effects of regulators and unavoidable ions on flotation were studied. Based on the results of single minerals flotation, the separation experiments of mixed minerals and bauxite ore were carried out. The results of closed circuit test on the ore show that, using RL as collector, Na 2CO 3 and (NaPO 3) 6 as modifiers, the grade of Al 2O 3 and SiO 2 are respectively 70.74% and 6.37% in concentrate (Al/Si 11.11), and the recovery of Al 2O 3 can reach 90.52%. 展开更多
关键词 COLLECTOR MODIFIER unavoidable ion flotation properties BAUXITE
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Review on development of low-grade scheelite recovery from molybdenum tailings in Luanchuan, China: A case study of Luoyang Yulu Mining Company 被引量:9
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作者 Xu WANG Wen-qing QIN +6 位作者 Fen JIAO Cong-ren YANG Wei LI Zheng-quan ZHANG Jin-min ZHOU Jian-gen GUO Jian ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第3期980-998,共19页
Luanchuan area is one of the regions with the largest scale of scheelite beneficiation and the largest output of scheelite concentrate in the world. After years of innovation and progress, the beneficiation technology... Luanchuan area is one of the regions with the largest scale of scheelite beneficiation and the largest output of scheelite concentrate in the world. After years of innovation and progress, the beneficiation technology of low-grade scheelite associated with molybdenum tailings in Luanchuan area is becoming more and more perfect. In this study, the development process of low-grade scheelite recycling technology in Luanchuan area was reviewed, including raw ore properties, beneficiation process, flotation equipment and flotation reagents. Meanwhile, taking Luoyang Yulu Mining Co., Ltd. as an example, the effects of various technical transformations such as the optimization of the beneficiation process, the column-machine combined process, and the high-efficiency flotation reagents were elucidated in detail. However, the recycling technology of low-grade scheelite of Luanchuan area is still possible to be improved. As a result, coupled with the latest research progress, the development direction of low-grade scheelite beneficiation in Luanchuan area was also prospected. It is of great significance to further improve the recovery efficiency of low-grade scheelite resources in Luanchuan area and this can provide technical reference for other scheelite plants. 展开更多
关键词 SCHEELITE low-grade ore BENEFICIATION FLOTATION RECOVERY
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Effective recovery of chalcopyrite at low temperatures using modified ester collector 被引量:6
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作者 Xian-zhong BU Yuan-yuan FENG +2 位作者 Ji-wei XUE Lu YANG Chong-hui ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第1期296-306,共11页
The effect of a modified ester collector named as BL on the flotation of chalcopyrite at low temperatures was investigated by micro-flotation tests,contact angle measurements,adsorption experiments,laser particle size... The effect of a modified ester collector named as BL on the flotation of chalcopyrite at low temperatures was investigated by micro-flotation tests,contact angle measurements,adsorption experiments,laser particle size analysis,cryogenic transmission electron microscopy(Cryo-TEM)and Fourier transform infrared(FTIR)analyses.Micro-flotation tests proved that the collecting ability of BL for chalcopyrite was significantly better than that of N,N-diethyl dithiocarbamate propiononitrile ester(ester-105)at low temperatures.Combined with laser particle size,Cryo-TEM and FTIR analyses,it was found that the particle size of BL in water was smaller than that of ester-105,and the distributed density of BL was higher than that of ester-105 at low temperatures,indicating that BL dispersed well at low temperatures.Therefore,BL was more easily adsorbed on the chalcopyrite surface and improved the surface hydrophobic degree of chalcopyrite,which were also confirmed by the contact angle measurements and adsorption experiments. 展开更多
关键词 modified ester collector chalcopyrite flotation collecting ability DISPERSIVITY low temperature reagent synthesis
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Mechanism and application on sulphidizing flotation of copper oxide with combined collectors 被引量:23
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作者 Wan-zhong YIN Qian-yu SUN +3 位作者 Dong LI Yuan TANG Ya-feng FU Jin YAO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第1期178-185,共8页
The effect of sodium butyl xanthate (NaBX) and dodecylamine (DDA) as combined collector on the sulphidizing flotation of copper oxide was investigated by flotation test, fluorescent pyrene probe, zeta potential, and i... The effect of sodium butyl xanthate (NaBX) and dodecylamine (DDA) as combined collector on the sulphidizing flotation of copper oxide was investigated by flotation test, fluorescent pyrene probe, zeta potential, and infrared spectroscopy analyses. The micro-flotation results show that combined use of NaBX+DDA yields better effect than using NaBX at pH 7-11 only, and the optimal molar ratio of NaBX to DDA is 2: 1. The actual ores flotation shows that when the dosage of NaBX+DDA is (100+54) g/t, the copper concentrate grade and recovery are 15.93% and 76.73%, respectively. The fluorescent pyrene probe test demonstrates that the NaBX+DDA can reduce the micelle concentration in the pulp. The zeta potential and the infrared spectroscopy analyses indicate that chemical adsorption, hydrogen-bonding and electrostatic interaction can help to adsorb NaBX+DDA on the surface of malachite. Meantime, copper xanthate and copper-amine complexes may be generated during the adsorption process. 展开更多
关键词 copper oxide combined collector FLOTATION ADSORPTION infrared spectroscopy
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Recovery of molybdenum and copper from porphyry ore via iso-flotability flotation 被引量:11
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作者 Qing-quan LIN Guo-hua GU +5 位作者 Hui WANG You-cai LIU Chong-qing WANG Jian-gang FU Jun-yao ZHAO Luo-luo HUANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第10期2260-2271,共12页
A copper-molybdenum iso-flotability flotation process has been developed to efficiently improve the recovery ofmolybdenite from Duobaoshan porphyry Cu-Mo ores.The effects of flotation approach,type of collector,feed p... A copper-molybdenum iso-flotability flotation process has been developed to efficiently improve the recovery ofmolybdenite from Duobaoshan porphyry Cu-Mo ores.The effects of flotation approach,type of collector,feed particle sizedistribution,rougher pH value and reagent dosage on the recovery of molybdenite were evaluated systematically.The results suggestthat compared with kerosene and diesel oil,transformer oil has stronger dispersion capability in water media and better flotationselectivity for molybdenite,providing a higher molybdenum recovery under low reagent dosage.Moreover,compared with bulkflotation approach,the iso-flotability flotation approach using transformer oil as a collector can obtain superior Mo recovery(90.77%)and grade(0.80%)in the cleaner concentrate,and increase the Mo recovery and grade by over18%and5%in the final Moconcentrate,respectively.The results of commercial flotation further indicate that the iso-flotability flotation approach is a rationaland effective route to beneficiate the porphyry Cu-Mo ores. 展开更多
关键词 copper-molybdenum ore iso-flotability flotation oily collector interfacial interaction flotation separation
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Oxygen pressure leaching-flotation joint process for Jinbaoshan platinum group minerals 被引量:2
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作者 Shuai RAO Zhi-qiang LIU +4 位作者 Xian-yang QIU Dong-xing WANG Hong-yang CAO WeiLI Jin-zhang TAO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第5期1090-1098,共9页
An oxygen pressure leaching-flotation joint process was proposed to treat Jinbaoshan platinum group minerals to produce a desired concentrate. The result demonstrates that leaching parameters which include particle si... An oxygen pressure leaching-flotation joint process was proposed to treat Jinbaoshan platinum group minerals to produce a desired concentrate. The result demonstrates that leaching parameters which include particle size, stirring speed, liquid-solid ratio, and the dosage of calcium lignosulfonate, simultaneously affect the leaching rates of base metals and the recovery of platinum group metals (PGMs). The complete dissolution of base metals sulfides leads to a reduction in the amount of flotation carrier for enriching PGMs, decreasing the recovery of PGMs. The optimum leaching conditions are determined as follows: liquid-solid ratio of 10 mL/g, 73% occupancy of ore particle size below 0.043 mm, stirring speed of 400 r/min, and 0.6 g dosage of calcium lignosulfonate. Under optimal conditions, the leaching rates of Cu, Ni and Fe are 87.6%, 87.6% and 90.3%, respectively. The grade of PGMs enriched in the flotation concentrate is 420 g/t through the flotation technology. 展开更多
关键词 platinum group metals oxygen pressure leaching FLOTATION RECOVERY
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Nano-microbubble flotation of fine and ultrafine chalcopyrite particles 被引量:30
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作者 Ahmadi Rahman Khodadadi Darban Ahmad +1 位作者 Abdollahy Mahmoud Fan Maoming 《International Journal of Mining Science and Technology》 SCIE EI 2014年第4期559-566,共8页
As is well known to mineral processing scientists and engineers, fine and ultrafine particles are difficult to float mainly due to the low bubble-particle collision efficiencies. Though many efforts have been made to ... As is well known to mineral processing scientists and engineers, fine and ultrafine particles are difficult to float mainly due to the low bubble-particle collision efficiencies. Though many efforts have been made to improve flotation performance of fine and ultrafine particles, there is still much more to be done. In this paper, the effects of nano-microbubbles (nanobuhbles and microbubbles) on the flotation of fine (-38 + 14.36 μm) and ultrafine (-14.36 + 5μm) chalcopyrite particles were investigated in a laboratory scale Denver flotation cell. Nano-microbubbles were generated using a specially-designed nano- microbubble generator based on the cavitation phenomenon in Venturi tubes. In order to better under- stand the mechanisms of nano-microbubble enhanced froth flotation of fine and ultrafine chalcopyrite particles, the nano-microbubble size distribution, stability and the effect of frother concentration on nano- bubble size were also studied by a laser diffraction method. Comparative flotation tests were performed in the presence and absence of nano-microbubbles to evaluate their impact on the fine and ultrafine chalcopyrite particle flotation recovery. According to the results, the mean size of nano-microbubbles increased over time, and decreased with increase of frother concentration. The laboratory-scale flotation test results indicated that flotation recovery of chalcopyrite fine and ultrafine particles increased by approximately 16-21% in the presence of nano-microbubbles, depending on operating conditions of the process. The presence of nano-microbubbles increased the recovery of ultrafine particles (-14.36 + 5 μm) more than that of fine particles (-38 + 14.36 μm). Another major advantage is that the use of nano-microbubbles reduced the collector and frother consumptions by up to 75% and 50%, respectively. 展开更多
关键词 Nanobubbles Nano-microbubble Bubble size distribution Chalcopyrite Froth flotation Fine particles
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