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Alkaline pressure oxidative leaching of bismuth-rich and arsenic-rich lead anode slime

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International Journal of Minerals,Metallurgy and Materials 2019年第6期26卷 689-700页

作者： Yun-long He rui-dong Xu Shi-wei He Han-sen Chen Kuo Li Yun Zhu Qing-feng Shen Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China

A new alkaline pressure oxidative leaching process(with NaNO3 as the oxidant and NaOH as the alkaline reagent)is proposed herein to remove arsenic,antimony,and lead from bismuth-rich and arsenic-rich lead anode slime for bismuth,gold,and silver *** effects of the temperature,liquid-to-solid ratio,leaching time,and reagent concentration on the leaching ratios of arsenic,antimony,and lead were investigated to identify the optimum leaching *** experimental results under optimized conditions indicate that the average leaching ratios of arsenic,antimony and lead are 95.36%,79.98%,63.08%,respectively.X-ray diffraction analysis indicated that the leaching residue is composed of Bi,Bi2O3,Pb2Sb2O7,and trace amounts of NaSb(OH)***,antimony,and lead are thus separated from lead anode slime as Na3AsO4·10H2O and *** electron microscopy and energy-dispersive spectrometry imaging revealed that the samples undergo appreciable changes in their surface morphology during leaching and that the majority of arsenic,lead,and antimony is removed.X-ray photoelectron spectroscopy was used to demonstrate the variation in the valence states of the arsenic,lead,and *** Pb(IV)and Sb(V)content was found to increase substantially with the addition of NaNO3.

关键词： lead anode slime pressure leaching arsenic removal antimony bismuth

A New Method for Monitoring Scattered Stray Light of an Inner-occulted Coronagraph

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Research in Astronomy and Astrophysics 2024年第2期24卷 216-227页

作者： Da-Yang Liu Hong-Xin Zhang Ming-Zhe Sun Zheng-Hua Huang Li-dong Xia Wei-Xin Liu Hui Fu Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

The scattered stray light of a coronagraph is a type of stray light that is generated by the objective lens as its surface defects are irradiated by *** defects mainly include dust and blemishes on the lens surface,microroughness of the lens surface,and impurity and inhomogeneity of the *** the other types of relatively stable defects introduced when the objective lens is being manufactured,the scattered stray light caused by dusts on the lens surface is difficult to quantify accurately due to the disorder and randomness of the dust *** contribution of this type of stray light to the overall stray light level is difficult to determine through simulations and *** can result in continuous deterioration of the stray light level of a coronagraph and thus affect the observation capabilities of the *** solve this issue,through analyzing the forming mechanism of scattered stray light and ghost image generated by the inner-occulted coronagraph,we propose a novel method to monitor the scattered stray light from dusts by utilizing different stray light correlation *** this method,we first simulate and measure the level of stray light from the ghost image of the objective lens,and then determine the flux ratio of scattered light and ghost image on the conjugate *** the flux ratio varies with the accumulation of dusts on the lens surface,it remains constant on the image ***,the level of dust scattering light on the image plane can be obtained by using this ratio together with the level of ghost image stray *** accuracy of this method has been validated in a laboratory by applying the objective lens with numerous surface cleanliness levels.

关键词： Sun corona-Sun atmosphere-instrumentation miscellaneous-methods analytical-techniques image processing

基于粒子群-支持向量机算法的激光诱导击穿光谱钢铁快速检测与分类

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光谱学与光谱分析 2024年第6期44卷 1559-1565页

作者：曾庆栋陈光辉李文鑫孟久灵李耿童巨红田志辉张晓林李国辉郭连波肖永军湖北工程学院物理与电子信息工程学院湖北孝感432000 华中科技大学武汉光电国家研究中心湖北武汉430074 湖北大学物理与电子科学学院湖北武汉430062

钢铁是国民经济中的支柱性产业,由于受生产技术的限制,我国钢铁产品主要集中为质量参差不齐的中低端产品,废品率较高,易造成资源浪费和环境污染。因此,钢铁产品的快速检测与鉴别分类,对保护环境以及提高钢铁资源的回收利用率有着重要意... 详细信息

钢铁是国民经济中的支柱性产业,由于受生产技术的限制,我国钢铁产品主要集中为质量参差不齐的中低端产品,废品率较高,易造成资源浪费和环境污染。因此,钢铁产品的快速检测与鉴别分类,对保护环境以及提高钢铁资源的回收利用率有着重要意义。利用激光诱导击穿光谱技术(LIBS)进行10种钢铁样品光谱数据的快速采集,并采用支持向量机(SVM)算法对其数据进行学习建模,得到钢铁快速分类模型。然而,由于不同钢铁样品的光谱数据特征是复杂且相似的,导致设置的模型参数也会对SVM模型的分类结果有着较大的影响。为了实现对不同牌号钢铁合金的快速检测分类,实验中采用粒子群算法(PSO)与网格寻优法两种不同方法来优化模型参数,并分别选取样品中6种微量元素(Mn、Cr、Cu、V、Mo、Ti)的17条特征谱线,和经主成分分析法(PCA)对全谱数据降维提取得到的前17个主成分作为模型的输入,建立PSO-SVM、PSO-PCA-SVM、PCA-SVM和SVM四种分类模型。实验结果表明,相比于精度最高的PCA-SVM模型的优化时间(257.84 s),PSO-SVM模型优化时间最短(11.5 s),且识别精度可达96.67%,与PCA-SVM模型的精度(97.5%)几乎相当。该结果表明LIBS结合PSO-SVM算法可实现快速的钢铁检测与分类,该方法为钢铁产品的快速检测与分类提供了一种新的解决途径。

关键词：激光诱导击穿光谱支持向量机粒子群算法钢铁分类

联合PS-InSAR和SBAS-InSAR的鄂西山区滑坡隐患识别——以长阳县清江流域为例

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安全与环境工程 2024年第2期31卷 202-212页

作者：曾斌刘诗雅董琦袁晶晶艾东中国地质大学(武汉)环境学院湖北武汉430078 湖北省地质局第七地质大队湖北宜昌443100

针对鄂西山区滑坡等灾害频发,而部分地区因为地形陡峭调查困难以及潜在滑坡隐患区的空间分布与未来发展趋势不明的难题,如何利用InSAR技术获取的地表形变数据实现滑坡隐患区早期识别成为滑坡研究的热门方向。利用Sentinel-1A升轨数据,... 详细信息

针对鄂西山区滑坡等灾害频发,而部分地区因为地形陡峭调查困难以及潜在滑坡隐患区的空间分布与未来发展趋势不明的难题,如何利用InSAR技术获取的地表形变数据实现滑坡隐患区早期识别成为滑坡研究的热门方向。利用Sentinel-1A升轨数据,分别基于PS-InSAR和SBAS-InSAR技术获取长阳县清江流域北岸2020年7月至2021年12月的地表形变信息,再将两种方法得到的地表形变信息进行叠加融合,综合考虑研究区的地质背景条件、历史滑坡点以及第四系覆盖层厚度等因素,识别出研究区可能发生滑坡的隐患区,并结合GNSS监测数据对识别结果进行可靠性分析。结果表明:基于PS-InSAR、SBAS-InSAR技术得到的研究区地表形变速率范围分别为-32.03~16.74 mm/a、-53.33~26.94 mm/a,根据自然断点法联合分析两种方法得到的监测结果,最终将研究区地表形变速率划分为5个等级,并识别出研究区有18处滑坡隐患区,总面积为27.58 km^(2),主要分布在研究区西部招徕河至资丘镇沿清江段;将PS与SBAS两种InSAR技术的解译结果进行融合判译,不仅能够进一步提高滑坡隐患区识别的精度,为区域地质灾害防控提供更加可靠的科学依据,同时也为基于InSAR技术的滑坡隐患区识别提供了新的思路。

关键词：滑坡隐患早期识别地表形变监测 PS-InSAR SBAS-InSAR 长阳县清江流域

Application of fecal immunochemical test in colorectal cancer screening:A community-based,cross-sectional study in averagerisk individuals in Hainan

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3445-3456页

作者： Fan Zeng Da-Ya Zhang Shi-Ju Chen Run-Xiang Chen Chen Chen Shi-Mei Huang Da Li Xiao-dong Zhang Jia-Jia Chen Cui-Yi Mo Lei Gao Jun-Tao Zeng Jian-Xin Xiong Zhai Chen Fei-Hu Bai Graduate School Hainan Medical UniversityHaikou 571199Hainan ProvinceChina Department of Gastroenterology Qionghai People’s HospitalQionghai 571400Hainan ProvinceChina Department of Gastroenterology Sanya Central HospitalSanya 572022Hainan ProvinceChina Department of Gastroenterology Hainan Second People’s HospitalWuzhishang 572299Hainan ProvinceChina Department of Gastroenterology Dongfang People’s HospitalDongfang 572699Hainan ProvinceChina Department of Gastroenterology The Second Affiliated Hospital of Hainan Medical UniversityHaikou 570216Hainan ProvinceChina The Gastroenterology Clinical Medical Center of Hainan Province Haikou 570216Hainan ProvinceChina

BACKGROUND The incidence of colorectal cancer(CRC)in China is steadily rising,with a high proportion of advanced-stage *** highlights the significance of early detection and prevention measures to enhance survival *** immunochemical testing(FIT)is a globally recommended CRC screening method;however,limited research has been conducted on its application in *** To assess the efficacy and adherence of FIT screening among average-risk individuals in Hainan,while also examining the risk factors associated with positive FIT *** This population-based cross-sectional study implemented FIT screening for CRC in 2000 asymptomatic participants aged 40-75 years from five cities and 21 community health centers in Hainan *** study was conducted from August 2022 to April 2023,employing a stratified sampling method to select *** with positive FIT results subsequently underwent *** predictive values for confirmed CRC and advanced adenoma were calculated,and the relationship between relevant variables and positive FIT results was analyzed usingχ2 tests and multivariate logistic *** A total of 1788 participants completed the FIT screening,with a median age of 57 years(interquartile range:40-75).Among them,503(28.1%)were males,and 1285(71.9%)were females,resulting in an 89.4%compliance rate for FIT *** overall positivity rate of FIT was 4.4%[79 out of 1788;95%confidence interval(CI):3%-5%].The specific positivity rates for Haikou,Sanya,Orient City,Qionghai City,and Wuzhishan City were 9.6%(45 of 468;95%CI:8%-11%),1.3%(6 of 445;95%CI:0.1%-3.1%),2.7%(8 of 293;95%CI:1.2%-4.3%),3.3%(9 of 276;95%CI:1.0%-6.3%),and 4.2%(11 of 406;95%CI:1.2%-7.3%),*** associations were found between age,dietary habits,and positive FIT *** of the 79 participants with positive FIT results,55 underwent colonoscopy,demonstrating an 82.2%compliance *** them,10 had a clean

关键词： Fecal immunochemical test Colorectal cancer Adenoma Screening Hainan Province

Myopia induced by flickering light in guinea pigs: a detailed assessment on susceptibility of different frequencies

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International Journal of Ophthalmology(English edition) 2013年第2期6卷 115-119页

作者： Yue Di rui Liu Ren-Yuan Chu Xing-Tao Zhou Xiao-dong Zhou Department of Ophthalmology Jinshan Hospital Fudan University Department of Ophthalmology Eye Ear Nose and Throat Hospital Fudan University

AIM: To investigate the effectiveness and feasibility of inducing myopia in guinea pigs by flickering light (FL) stimulation with different frequencies. METHODS: Seventy 2 -week-old guinea pigs were randomly assigned to six groups: five FL groups and a control group (n =12 for each). Animals in the five FL groups were raised under 500lx illumination with a duty diurnal cycle of 50% at a flash rate of 5, 1, 0.5, 0.25 and 0.1Hz respectively. Those in the control group were reared under steady 250lx illumination. Refraction, axial length, and radius of curvature were measured before and at 2, 4, 6, 8, 10 and 12 weeks after treatment. At week 12, the eyeballs were taken out and three ocular dimensions and dry weight of sclera were measured. RESULTS: A myopic shift and axial eye length increase developed in the five FL groups. Stimulation at 0.5Hz caused greater changes in myopic shift, axial elongation, eyeball dimension, and dry weight of sclera than stimulation at other frequencies. Compared with controls, eyes in 0.5Hz group were approximately -5.5 ±1.5D more myopic with increase in horizontal, vertical, axial dimensions by 0.89 ±0.3mm, 0.69 ±0.2mm, 1.12 ±0.2mm respectively and with increase in dry weight of sclera by 0.44mg. CONCLUSION: Chronic exposure to periodic illumination at temporal frequency is attended by development of excessive ocular enlargement and myopic refractive error. Emmetropization could bedisrupted differently by frequency alteration.

关键词： myopia flickering illumination stimulus guinea pig animal model eye development

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珙桐体细胞胚胎发生技术研究

西北林学院学报 2024年第2期39卷 70-78页

作者：令狐高曼季晓莲段榕怡刘睿戴钊董嘉明徐金颢康永祥西北农林科技大学林学院陕西杨陵712100 杨凌职业技术学院陕西杨陵712100

研究探讨基本培养基类型对珙桐愈伤组织诱导的影响、植物生长调节剂对胚性愈伤组织诱导及体胚发育的影响,初步建立以未成熟合子胚为外植体,通过体细胞胚胎发生途径再生珙桐植株的培养方案。结果表明,在含有3%蔗糖、0.3%凝胶、800 mg/L... 详细信息

研究探讨基本培养基类型对珙桐愈伤组织诱导的影响、植物生长调节剂对胚性愈伤组织诱导及体胚发育的影响,初步建立以未成熟合子胚为外植体,通过体细胞胚胎发生途径再生珙桐植株的培养方案。结果表明,在含有3%蔗糖、0.3%凝胶、800 mg/L水解酪蛋白、400 mg/L L-谷氨酰胺的MS、1/2MS和WPM基本培养基上均可诱导出愈伤组织,以MS+2.0 mg/L 2,4-D+0.5 mg/L 6-BA诱导率最高,可达94.0%;胚性愈伤组织在MS+0.5 mg/L NAA+1.0 mg/L 6-BA的培养基上诱导效果较好;在MS+0.5 mg/L NAA+1.0 mg/L 6-BA培养基上,体胚诱导率可达22.9%;成熟体胚在1/2MS+0.5 mg/L 6-BA+0.25 mg/L IBA的萌发培养基上能正常萌发,其后在添加1 g/L活性炭的萌发培养基上转化成完整小植株。组织细胞学观察表明,珙桐体胚起源于胚性愈伤组织,经历了球形期、心形期、鱼雷期和子叶期发育阶段,这与自然条件下的合子胚形成过程相似。

关键词：珙桐胚性愈伤组织体细胞胚植株再生组织细胞学

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D^(+)→π^(+)v■decay process within the QCDSR approach

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Chinese Physics C 2024年第6期48卷 69-81页

作者：陈宇付海冰钟涛吴胜波黄冬 Department of Physics Guizhou Minzu UniversityGuiyang 550025China Center of Experimental Training Guiyang Institute of Information Science and TechnologyGuiyang 550025China

In this paper,we investigate the charmed meson rare decay process D^(+)→π^(+)v■using an approach based on QCD sum ***,the pion twist-2,3 distribution amplitude(DA)moments|μ,are calculated up to the tenth and fourth orders,respectively,in the QCD sum rules according to the background field *** constructing the light-cone harmonic oscillator model for the pion twist-2,3 D As,we obtain their behaviors by matching the calculatedξ-***,the D→πtransition form factors(TFFs)are calculated using an approach based on QCD light-cone sum *** vector form factor at the large recoil region is f_(+)^(D)→^(π)(0)=0.627_(-0.080)^(+0.120).Using the rapidly converging simplified series expansion of z(q^(2),t),we present the TFFs and corresponding angular coefficients in the whole squared momentum transfer physical *** on nonstandard neutrino interactions,the■^(0)→π^(+)e■_(e)decay can be related to the■^(0)→π^(+)e■_(e)decay ***,we first describe the semileptonic decay process■^(0)→π^(+)e■_(e),differential decay widths,and branching fraction with B(■^(0)→π^(+)e■_(e))=0.308_(-0.066)^(+0.155)×10^(2).The■^(0)→π^(+)e■_(e)differential/total predictions for forward-backward asymmetry,q^(2)-differential flat terms,and lepton polarization asymmetry are also *** prediction for the D^(+)→π^(+)v■branching fraction isB(D^(+)→π^(+)v■)=1.85_(-0.46)+^(0.93)×10^(-8).

关键词： transition form factors pion LCDAs flavour changing neutral current transition heavy meson semileptonic decays QCD sum rule

苓泽降脂汤联合多烯磷脂酰胆碱胶囊对非酒精性脂肪性肝病患者的临床疗效

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中成药 2024年第7期46卷 2220-2224页

作者：邢东刘建伟张掖市第二人民医院甘肃张掖734000

目的探讨苓泽降脂汤联合多烯磷脂酰胆碱胶囊对非酒精性脂肪性肝病患者的临床疗效。方法80例患者随机分为对照组和观察组,每组40例,对照组给予多烯磷脂酰胆碱胶囊,观察组在对照组基础上加用苓泽降脂汤,疗程3个月。检测临床疗效、血脂指标... 详细信息

目的探讨苓泽降脂汤联合多烯磷脂酰胆碱胶囊对非酒精性脂肪性肝病患者的临床疗效。方法80例患者随机分为对照组和观察组,每组40例,对照组给予多烯磷脂酰胆碱胶囊,观察组在对照组基础上加用苓泽降脂汤,疗程3个月。检测临床疗效、血脂指标(TC、HDL-C、LDL-C、TG)、血糖指标(HbA1c、FPG)、LPS、氧化应激指标(T-AOC、SOD、NO)、胰岛素敏感性指标(GLUT4、IRS1、IRS2)、肝功能指标(ALT、AST)、肝损伤指标(γ-2GT、TGF-β、LEP、核因子κB)、中医证候评分变化。结果观察组总有效率高于对照组(P<0.05)。治疗后,2组TC、LDL-C、TG、血糖指标、LPS、NO、肝功能指标、肝损伤指标、中医证候评分降低(P<0.05),HDL-C、T-AOC、SOD、胰岛素敏感性指标升高(P<0.05),以观察组更明显(P<0.05)。结论苓泽降脂汤联合多烯磷脂酰胆碱胶囊可改善非酒精性脂肪性肝病患者糖脂代谢、胰岛素敏感性和肝功能,抑制炎症,减少氧化应激损伤和肝损伤,提升临床疗效。

关键词：苓泽降脂汤联合多烯磷脂酰胆碱胶囊非酒精性脂肪性肝病