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A nomogramfor predicting overall survival in patients with low-grade endometrial stromal sarcoma: A population-based analysis 被引量:70
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作者 Jie Wu Huibo Zhang +4 位作者 Lan Li Mengxue Hu Liang Chen Bin Xu Qibin Song 《Cancer Communications》 SCIE 2020年第7期301-312,共12页
Background:Low-grade endometrial stromal sarcoma(LG-ESS)is a rare tumor that lacks a prognostic prediction model.Our study aimed to develop a nomogram to predict overall survival of LG-ESS patients.Methods:A total of ... Background:Low-grade endometrial stromal sarcoma(LG-ESS)is a rare tumor that lacks a prognostic prediction model.Our study aimed to develop a nomogram to predict overall survival of LG-ESS patients.Methods:A total of 1172 patients confirmed to have LG-ESS between 1988 and 2015 were selected from the Surveillance,Epidemiology and End Results(SEER)database.They were further divided into a training cohort and a validation cohort.The Akaike information criterion was used to select variables for the nomogram.The discrimination and calibration of the nomogram were evaluated using concordance index(C-index),area under time-dependent receiver operating characteristic curve(time-dependent AUC),and calibration plots.The net benefits of the nomogram at different threshold probabilities were quantified and compared with those of the International Federation of Gynecology and Obstetrics(FIGO)criteria-based tumor staging using decision curve analysis(DCA).Net reclassification index(NRI)and integrated discrimination improvement(IDI)were also used to compare the nomogram’s clinical utilitywith that of the FIGO criteria-based tumor staging.The risk stratifications of the nomogram and the FIGO criteria-based tumor staging were compared.Results:Seven variables were selected to establish the nomogram for LG-ESS.The C-index(0.814 for the training cohort and 0.837 for the validation cohort)and the time-dependent AUC(>0.7)indicated satisfactory discriminative ability of the nomogram.The calibration plots showed favorable consistency between the prediction of the nomogram and actual observations in both the training and validation cohorts.The NRI values(training cohort:0.271 for 5-year and 0.433 for 10-year OS prediction;validation cohort:0.310 for 5-year and 0.383 for 10-year OS prediction)and IDI(training cohort:0.146 for 5-year and 0.185 for 10-year OS prediction;validation cohort:0.177 for 5-year and 0.191 for 10-year OS prediction)indicated that the established nomogram performed significantly better than the FIGO criteria-based 展开更多
关键词 FIGO criteria-based tumor staging low-grade endometrial stromal sarcoma(LG-ESS) NOMOGRAM overall survival prognostic model risk stratification
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Irritable bowel syndrome:Diagnosis and pathogenesis 被引量:51
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作者 Magdy El-Salhy 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第37期5151-5163,共13页
Irritable bowel syndrome (IBS) is a common gastro-intestinal (GI) disorder that considerably reduces the quality of life. It further represents an economic burden on society due to the high consumption of healthcare r... Irritable bowel syndrome (IBS) is a common gastro-intestinal (GI) disorder that considerably reduces the quality of life. It further represents an economic burden on society due to the high consumption of healthcare resources and the non-productivity of IBS patients. The diagnosis of IBS is based on symptom assessment and the Rome Ⅲ criteria. A combination of the Rome Ⅲ criteria, a physical examination, blood tests, gastros-copy and colonoscopy with biopsies is believed to be necessary for diagnosis. Duodenal chromogranin A cell density is a promising biomarker for the diagnosis of IBS. The pathogenesis of IBS seems to be multifactorial, with the following factors playing a central role in the pathogenesis of IBS:heritability and genetics, dietary/intestinal microbiota, low-grade inflammation, and disturbances in the neuroendocrine system (NES) of the gut. One hypothesis proposes that the cause of IBS is an altered NES, which would cause abnormal GI motility, secretions and sensation. All of these abnormalities are characteristic of IBS. Alterations in the NES could be the result of one or more of the following:genetic factors, dietary intake, intestinal flora, or lowgrade inflammation. Post-infectious IBS (PI-IBS) and inflammatory bowel disease-associated IBS (IBD-IBS) represent a considerable subset of IBS cases. Patients with PI-and IBD-IBS exhibit low-grade mucosal inflammation, as well as abnormalities in the NES of the gut. 展开更多
关键词 CHOLECYSTOKININ Chromogranin A Diagno-sis DIET Endocrine cells Intestinal flora HEREDITARY low-grade inflammation Peptide YY SEROTONIN
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苏打烧结法处理低品位钨矿及废钨渣的研究 被引量:31
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作者 杨利群 《中国钼业》 2008年第4期25-27,共3页
进行了苏打烧结法处理低品位钨矿和废钨渣的研究。苏打烧结法处理低品位、难处理黑白钨矿和废钨渣都能有效地使其分解,渣中钨可降至0.5%以下。此外,处理这类相对低价的钨矿物可取得比较可观的经济效益。
关键词 苏打烧结法 低品位 废钨渣
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低品位双重难处理金矿石工艺矿物学及浸金影响因素 被引量:29
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作者 杨洪英 巩恩普 杨立 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2008年第12期1742-1745,共4页
试验所用矿石来自我国云南某金矿,该矿含金2.4 g/t,砷0.97%,碳1.47%.它是典型的低品位含碳双重难处理金矿石,浮选精矿-氰化提金,金浸出率为10.43%;浮选精矿-焙烧-氰化工艺,金浸出率为46.52%,属于极难浸金矿.矿石主要金属矿物为黄铁矿、... 试验所用矿石来自我国云南某金矿,该矿含金2.4 g/t,砷0.97%,碳1.47%.它是典型的低品位含碳双重难处理金矿石,浮选精矿-氰化提金,金浸出率为10.43%;浮选精矿-焙烧-氰化工艺,金浸出率为46.52%,属于极难浸金矿.矿石主要金属矿物为黄铁矿、毒砂.脉石矿物主要为石英、绢云母、白云石、方解石、伊利石黏土矿物等.金的赋存状态绝大多数是"不可见金",主要为次显微、超显微的包裹金以及胶体金.金主要包裹于毒砂和黄铁矿晶体中.矿石中金矿物主要为自然金,少为银金矿.矿石金回收率低的原因主要是包裹金,矿石含砷、碳质以及黏土矿物. 展开更多
关键词 低品位 双重难处理金矿石 碳质 工艺矿物学 浸金
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低品位钒钛磁铁矿选铁尾矿综合回收钛试验研究 被引量:28
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作者 龙运波 张裕书 《矿业快报》 2007年第7期22-24,共3页
针对低品位钒钛磁铁矿选铁尾矿含钛低、含橄榄石和钛普通辉石高、矿石工艺性质复杂难选的特点,开展了综合回收钛的试验研究。研究结果表明:采用强磁预选-浮选工艺,可以获得含TiO248.01%、回收率36.40%(对选铁尾矿)的较高质量的钛精矿产品。
关键词 钒钛磁铁矿 钛铁矿 低品位 综合回收钛 强磁选 浮选
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某低品位原生金矿选矿试验研究 被引量:27
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作者 张成强 李洪潮 +1 位作者 张红新 田敏 《中国矿业》 北大核心 2010年第11期89-91,共3页
对某低品位原生金矿进行了选矿试验研究。通过对浮选指标各影响因素的优化,得出了粗选最佳选别条件:磨矿细度-200目65%;pH值调整剂碳酸钠用量1500g/t,相应pH值为8.5;浮选浓度31%;丁基黄药用量60g/t;2#油用量35g/t。在此条件下,进行了一... 对某低品位原生金矿进行了选矿试验研究。通过对浮选指标各影响因素的优化,得出了粗选最佳选别条件:磨矿细度-200目65%;pH值调整剂碳酸钠用量1500g/t,相应pH值为8.5;浮选浓度31%;丁基黄药用量60g/t;2#油用量35g/t。在此条件下,进行了一次粗选、三次精选、两次扫选的实验室闭路试验,可获得金精矿品位29.8g/t、回收率为94.59%的较好指标。试验结果表明,该低品位金矿可以通过浮选达到预先富集的目的。 展开更多
关键词 低品位 原生金矿 浮选 可浮性
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Hepatic steatosis,low-grade chronic inflammation and hormone/growth factor/adipokine imbalance 被引量:24
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作者 Giovanni Tarantino Silvia Savastano Annamaria Colao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第38期4773-4783,共11页
Non-alcoholic fatty liver disease (NAFLD), a further expression of metabolic syndrome, strictly linked to obesity and diabetes mellitus, is characterized by insulin resistance (IR), elevated serum levels of free fatty... Non-alcoholic fatty liver disease (NAFLD), a further expression of metabolic syndrome, strictly linked to obesity and diabetes mellitus, is characterized by insulin resistance (IR), elevated serum levels of free fatty acids and fatty infi ltration of the liver, which is known as hepatic steatosis. Hepatocyte apoptosis is a key feature of this disease and correlates with its severity. Free-fatty-acidinduced toxicity represents one of mechanisms for the pathogenesis of NAFLD and hormones, growth factors and adipokines influence also play a key role. This review highlights the various pathways that contribute to the development of hepatic steatosis. Circulating concentrations of inflammatory cytokines are reckoned to be the most important factor in causing and maintaining IR. Low-grade chronic inflammation is fundamental in the progression of NAFLD toward higher risk cirrhotic states. 展开更多
关键词 Hepatic steatosis low-grade chronic inflammation ADIPOKINES HORMONES Growth factors
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低品位铜矿资源开发利用状况和选矿工艺技术综述 被引量:23
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作者 贾振宏 胡凤英 《有色矿冶》 2014年第2期22-24,21,共4页
随着我国铜消费量的急剧增加和国内资源保证程度不断下降,急需对复杂低品位铜矿资源进行开发利用,以缓解我国铜原料长期依赖进口的矛盾。本文对铜资源状况、我国主要产铜基地以及低品位铜矿选矿工艺技术进行了综合阐述。
关键词 铜资源 基地 浮选 浸出 低品位
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低品位白钨矿选矿技术的研究发展 被引量:22
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作者 黎继永 谢贤 +2 位作者 童雄 侯凯 杨子轩 《矿产综合利用》 CAS 北大核心 2015年第4期1-6,11,共7页
系统地介绍我国低品位白钨矿选矿技术现状及发展。详细阐述了浮选、非浮选选矿工艺以及选矿联合工艺在低品位白钨矿的选矿中的作用及其进展。重点指出对于品位低、组分复杂、细粒嵌布的白钨矿,单一选矿工艺已经很难解决问题,加大力度研... 系统地介绍我国低品位白钨矿选矿技术现状及发展。详细阐述了浮选、非浮选选矿工艺以及选矿联合工艺在低品位白钨矿的选矿中的作用及其进展。重点指出对于品位低、组分复杂、细粒嵌布的白钨矿,单一选矿工艺已经很难解决问题,加大力度研究重、磁、浮、化等选矿工艺之间联系,组成联合工艺,实现各个工艺之间的优劣势互相补充,协同效应最大化,是未来大力度开发利用低品位白钨矿,保持我国钨业持续发展的发展方向。 展开更多
关键词 白钨矿 低品位 混合矿 浮选 联合工艺.
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某低品位方解石-石英型萤石浮选试验研究 被引量:22
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作者 艾光华 梁焘茂 +1 位作者 袁勤智 李继福 《非金属矿》 CAS CSCD 北大核心 2018年第1期70-72,共3页
某方解石-石英型萤石矿CaF_2含量为25.32%,属低品位萤石矿。浮选试验在粗选磨矿细度-74μm占75%,粗精矿再磨细度选择为-74μm占85%的条件下,以碳酸钠作调整剂,水玻璃作抑制剂,油酸作捕收剂,采用"1粗7精2扫-粗精矿再磨"工艺流... 某方解石-石英型萤石矿CaF_2含量为25.32%,属低品位萤石矿。浮选试验在粗选磨矿细度-74μm占75%,粗精矿再磨细度选择为-74μm占85%的条件下,以碳酸钠作调整剂,水玻璃作抑制剂,油酸作捕收剂,采用"1粗7精2扫-粗精矿再磨"工艺流程进行闭路试验,最终得到CaF_2含量为96.33%、CaCO_3含量为0.89%,回收率为70.07%的萤石精矿。 展开更多
关键词 低品位 再磨 萤石 方解石 浮选
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Oxidation process of low-grade vanadium slag in presence of Na_(2)CO_3 被引量:22
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作者 李新生 谢兵 +1 位作者 王广恩 李晓军 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第8期1860-1867,共8页
The oxidation process of low-grade vanadium slag in the presence of Na2CO3 was investigated by XRD,SEM/EDS and TG-DSC techniques.The results show that the vanadium slag is oxidized in a temperature range from 273 to 7... The oxidation process of low-grade vanadium slag in the presence of Na2CO3 was investigated by XRD,SEM/EDS and TG-DSC techniques.The results show that the vanadium slag is oxidized in a temperature range from 273 to 700 °C.Olivine phases and spinel phases are completely decomposed at 500 and 600 °C,respectively.Most of water-soluble sodium vanadates are formed between 500 and 600 °C.When roasting temperature reaches above 700 °C,the vanadium-rich phases of sodium vanadates can be obviously observed.However,at temperature above 800 °C,the samples are sintered.Most of the vanadium is enwrapped by glassy phase compounds which lead to the decrease of the leaching rate of vanadium.At the same time,the effect of roasting temperature on extraction of vanadium and characterization of leach residues were discussed. 展开更多
关键词 low-grade vanadium slag NA2CO3 ROASTING vanadium-rich phases LEACHING
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复杂难选铜铅锌矿选矿工艺研究 被引量:18
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作者 许运寿 蔡有兴 《湖南有色金属》 CAS 2000年第3期13-14,共2页
对复杂硫化矿进行铜铅锌分离研究 ,采用铜铅混浮 ,铅进一步用摇床富集提纯 ,获得良好的选别效果 ,得到铜铅锌三种合格产品。
关键词 混合浮选 选矿工艺 铜铅锌矿 硫化硫
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低孔隙度低渗透率储层压裂后产能测井预测方法研究 被引量:21
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作者 张丽华 潘保芝 +3 位作者 庄华 郭立新 李庆峰 赵小青 《测井技术》 CAS CSCD 北大核心 2012年第1期101-105,共5页
通过研究影响压裂后产能的各种参数,对低孔隙度低渗透率的朝阳沟油田进行了压裂后产能预测。对压裂后产能影响较大的参数有地层有效渗透率、有效厚度、井底流压等。确定了该区产能级别划分标准,提出2种预测方法:方程法和神经网络法。建... 通过研究影响压裂后产能的各种参数,对低孔隙度低渗透率的朝阳沟油田进行了压裂后产能预测。对压裂后产能影响较大的参数有地层有效渗透率、有效厚度、井底流压等。确定了该区产能级别划分标准,提出2种预测方法:方程法和神经网络法。建立了朝阳沟油田预测压裂后产能的无限导流能力垂直裂缝稳态流方程,并给出了各参数的计算方法。应用方程法对11口井的压裂后产能进行预测,判别单层测试产油级别符合率为73%。应用神经网络法,选取研究区13口井进行训练和验证,单层测试产油级别符合率为100%。 展开更多
关键词 测井评价 产能预测 压裂 低孔隙度 低渗透率 产能级别 方程法 神经网络法
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Leaching kinetics of low-grade copper ore containing calcium-magnesium carbonate in ammonia-ammonium sulfate solution with persulfate 被引量:20
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作者 刘志雄 尹周澜 +1 位作者 胡慧萍 陈启元 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2822-2830,共9页
The leaching kinetics of copper from low-grade copper ore was investigated in ammonia-ammonium sulfate solution with sodium persulfate. The effect parameters of stirring speed, temperature, particle size, concentratio... The leaching kinetics of copper from low-grade copper ore was investigated in ammonia-ammonium sulfate solution with sodium persulfate. The effect parameters of stirring speed, temperature, particle size, concentrations of ammonia, ammonium sulfate and sodium persulfate were determined. The results show that the leaching rate is nearly independent of agitation above 300 r/min and increases with the increase of temperature, concentrations of ammonia, ammonium sulfate and sodium persulfate. The EDS analysis and phase quantitative analysis of the residues indicate that bornite can be dissolved by persulfate oxidization. The leaching kinetics with activation energy of 22.91 kJ/mol was analyzed by using a new shrinking core model (SCM) in which both the interfacial transfer and diffusion across the product layer affect the leaching rate. A semi-empirical rate equation was obtained to describe the leaching process and the empirical reaction orders with respect to the concentrations of ammonia, ammonium sulfate and sodium persulfate are 0.5, 1.2 and 0.5, respectively. 展开更多
关键词 low-grade copper ore calcium-magnesium carbonate leaching kinetics ammoniacal solution sodium persulfate activation energy shrinking cure model
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试论“低品位”油气资源 被引量:17
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作者 查全衡 何文渊 《石油勘探与开发》 SCIE EI CAS CSCD 北大核心 2003年第6期5-7,共3页
"低品位"资源是一个相对概念,是相对于已发现的规模大、丰度高、油品好、产量高油气田的"高品位"资源而言的,也是相对于一定时期的技术经济条件而言的。自然界中的"低品位"资源数量相当大,有些盆地的&qu... "低品位"资源是一个相对概念,是相对于已发现的规模大、丰度高、油品好、产量高油气田的"高品位"资源而言的,也是相对于一定时期的技术经济条件而言的。自然界中的"低品位"资源数量相当大,有些盆地的"低品位"资源总量可以等于甚至超过"高品位"资源总量,其重要性不容忽视。发达国家十分重视对本土"低品位"资源的利用。我国存在大量"低品位"资源,随着勘探程度的加深和技术的进步,其地位将日益重要。 展开更多
关键词 油气资源 低品位 开发
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Recent developments in the pathophysiology of irritable bowel syndrome 被引量:19
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作者 Magdy El-Salhy 《World Journal of Gastroenterology》 SCIE CAS 2015年第25期7621-7636,共16页
Irritable bowel syndrome(IBS) is a common gastrointestinal disorder, the pathophysiology of which is not completely known, although it has been shown that genetic/social learning factors, diet, intestinal microbiota, ... Irritable bowel syndrome(IBS) is a common gastrointestinal disorder, the pathophysiology of which is not completely known, although it has been shown that genetic/social learning factors, diet, intestinal microbiota, intestinal low-grade inflammation, and abnormal gastrointestinal endocrine cells play a major role. Studies of familial aggregation and on twins have confirmed the heritability of IBS. However, the proposed IBS risk genes are thus far nonvalidated hits rather than true predisposing factors. There is no convincing evidence that IBS patients suffer from food allergy/intolerance, with the effect exerted by diet seemingly caused by intake of poorly absorbed carbohydrates and fiber. Obesity is a possible comorbidity of IBS. Differences in the microbiota between IBS patients and healthy controls have been reported, but the association between IBS symptoms and specific bacterial species is uncertain. Low-grade inflammation appears to play a role in the pathophysiology of a major subset of IBS, namely postinfectious IBS. The density of intestinal endocrine cells is reduced in patients with IBS, possibly as a result of genetic factors, diet, intestinal microbiota, and low-grade inflammation interfering with the regulatory signals controlling the intestinal stem-cell clonogenic and differentiation activities. Furthermore, there is speculation that this decreased number of endocrine cells is responsible for the visceral hypersensitivity, disturbed gastrointestinal motility, and abnormal gut secretion seen in IBS patients. 展开更多
关键词 DIET Endocrine cells Genetic factors low-grade inflammation MICROBIOTA Stem cells
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高钙低品位石煤提取五氧化二钒新工艺 被引量:18
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作者 姚金江 吴海国 李婕 《湖南有色金属》 CAS 2009年第6期21-23,61,共4页
文章对高钙低品位石煤提钒工艺进行了研究,提出了选矿冶炼联合提钒新工艺,并获得了理想的浸出效果。该工艺与传统工艺相比,可有效降低冶炼成本,提高钒的回收率,开辟了低品位石煤钒矿提取五氧化二钒新途径,提高了低品位钒矿的资源综合利... 文章对高钙低品位石煤提钒工艺进行了研究,提出了选矿冶炼联合提钒新工艺,并获得了理想的浸出效果。该工艺与传统工艺相比,可有效降低冶炼成本,提高钒的回收率,开辟了低品位石煤钒矿提取五氧化二钒新途径,提高了低品位钒矿的资源综合利用率。 展开更多
关键词 高钙 低品位 石煤 五氧化二钒
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川西某低品位锂辉石矿分选试验研究 被引量:19
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作者 程仁举 李成秀 +2 位作者 刘星 王昌良 徐莺 《有色金属(选矿部分)》 北大核心 2017年第5期42-45,50,共5页
川西某低品位锂矿为伟晶岩型矿石,其有用矿物主要为锂辉石,Li_2O品位为1.20%,在目前的技术和经济条件下,该矿的开发利用具有显著的经济效益和社会效益。在磨矿细度为-74μm含量78.3%的情况下,采用一次粗选、两次扫选、三次精选、中矿顺... 川西某低品位锂矿为伟晶岩型矿石,其有用矿物主要为锂辉石,Li_2O品位为1.20%,在目前的技术和经济条件下,该矿的开发利用具有显著的经济效益和社会效益。在磨矿细度为-74μm含量78.3%的情况下,采用一次粗选、两次扫选、三次精选、中矿顺序返回的浮选闭路流程,可获得Li_2O品位5.69%,回收率为83.06%的锂精矿。 展开更多
关键词 锂辉石 低品位 浮选 捕收剂
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磷尾矿综合利用研究进展 被引量:18
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作者 周雪娜 关洪亮 +3 位作者 何东升 宋国平 张可成 朱志伟 《广州化工》 CAS 2021年第5期24-27,共4页
磷矿是一种不可再生的重要化工矿产资源,经过大量的开采,其资源日渐贫乏。我国磷矿不富,需要经过选矿富集才能得到更加有效的利用,所产生的大量的尾矿堆积造成环境污染。大量磷尾矿中富含钙、镁、磷资源,加以回收利用,具有重要的经济价... 磷矿是一种不可再生的重要化工矿产资源,经过大量的开采,其资源日渐贫乏。我国磷矿不富,需要经过选矿富集才能得到更加有效的利用,所产生的大量的尾矿堆积造成环境污染。大量磷尾矿中富含钙、镁、磷资源,加以回收利用,具有重要的经济价值和社会意义。根据目前行业内发展状况,综述了目前国内磷尾矿综合利用的现状,阐述了磷尾矿回收和利用的多种途径和方法,并提出了建议。 展开更多
关键词 磷尾矿 低品位 环境污染 综合利用
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某低品位难选金矿浮选试验研究 被引量:18
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作者 李丽君 易峦 卢央泽 《金属材料与冶金工程》 CAS 2012年第3期22-26,共5页
某低品位难选金矿含金0.86 g/t,根据其性质特点,采用MA和丁胺黑药组合药剂,进行磨矿-二粗一扫三精的浮选工艺流程试验,最终可获得精矿金品位21.40 g/t,回收率84.41%的浮选闭路指标,金得到很好的回收。
关键词 低品位 金矿 组合用药 浮选
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