检索结果-南通市图书馆

Selective precipitation and non-isothermal crystallization kinetics of britholite from low grade REE-bearing slag

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2023年第11期41卷 1812-1818,I0006页

作者： Zhuang ma Zengwu Zhao Xingqi Guo Wentao Guo School of materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou014010China Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou014010China Inner Mongolia Autonomous Regional Engineering technology Research Center of Sustainable Exploitation of Rare Earth Secondary Resources Inner Mongolia University of Science and TechnologyBaotou014010China

In order to improve the recovery rate of rare earth,the effect of P_(2)O_(5) and cooling rate on the selective precipitation of caO-SiO_(2)-tiO_(2)-P_(2)O_(5)-nb_(2)O_(5)-CeO_(2)-caF_(2) slag system was explored using X-ray powder diffraction,a scanning electron microscope,an electron probe micro-analyzer and a confocal laser scanning *** apatite(ca_(2.02)Ce_(7.98)Si_(6.00)O_(26.00))is tiny and difficult to be separated from the slag without P_(2)O_(5).When the addition of P_(2)O_(5) is 6 wt%-10 wt%,the cerium and phosphorus are found to be enriched in britholite(ca_(5-x)Ce_(x)[(SiO_(4))_(x)(po_(4))_(3-x)]F)phase while x is negatively correlated with P_(2)O_(5) content in the *** influence of P_(2)O_(5) and cooling rate on the non-isothermal crystallization kinetics was also *** the cooling rate between 5 and 40℃/min,continuous cooling transformation diagram of britholite was constructed when the P205 content is between 6 wt%-10 wt%.the modified Avrami model was applied to determine the crystallization mode of slag with 10 wt%P_(2)O_(5).It is shown that the crystallization mode is diffusion-controlled with constant nucleation rate and one-dimensional *** consideration of quantity and volume of crystals,the reasonable cooling rate is between 10and 30℃/min.

关键词： P_(2)O_(5) Crystallization Kinetics Low grade REE-bearing slag Rare earths

Road to identifying endpoint biomarkers in the treatment of nonalcoholic steatohepatitis: are we there yet?

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary Surgery and nutrition 2020年第2期9卷 244-246页

作者： Donghee Kim luis Miguel Vazquez-Montesino Aijaz Ahmed Division of Gastroenterology and Hepatology Stanford University School of MedicineStanfordCAUSA Department of Medicine Stanford University School of MedicineStanfordCAUSA

In the United States(US),the landscape of chronic liver disease has been in flux in recent years as chronic hepatitis C virus(HCV)infection is no longer the leading indication for liver transplantation and now ranks behind alcoholic liver disease(ALD)and nonalcoholic steatohepatitis(nASH)as the third leading indication for liver transplantation(1).the approval of second-generation direct-acting antiviral(DAA)agents in late 2013 heralded a revolutionary era in the treatment of HCV *** a recent population-based study,there was a marked increase in age-standardized mortality for HCV infection with annual percent change(APC)of 2.2%in the pre-DAA era[2007-2014],but a marked decline in age-standardized mortality rates for HCV in the DAA-era[2014-2017]with-6.5%of APC(2).While HCV-related mortality declined along with the introduction of DAA therapies,nonalcoholic fatty liver disease(nAFLD)-related death was on the rise at an accelerated pace in the US adults(3).notably,age-standardized mortality for nASH-related cirrhosis increased significantly between 2007 and 2016(APC:15.4%;95%CI:14.1 to 16.7)(4).nAFLD-related advanced fibrosis remains a topic of interest because of its association with end-stage liver disease and hepatocellular *** the last 10 years from 2005 to 2016,nAFLD-related advanced fibrosis increased from 3%among subjects with nAFLD in 2005-2008 to 6%in 2013-2016 in the US adults(5).the prevalence of nAFLD-related advanced fibrosis is now estimated to be four million US adults(5).Longitudinal cohort studies looking into patients with nAFLD suggest that the fibrosis stage,and not the presence of nASH,predicted both the risk of overall and cause-specific mortality(6,7).

关键词： mortality treatment approval

Electrochemical and spectroscopic study of interfacial interactions between chalcopyrite and typical flotation process reagents

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and materials 2016年第2期23卷 127-136页

作者： Gustavo Urbano Isabel Lázaro Israel Rodríguez Juan luis Reyes Roxana Larios Roel Cruz Instituto de Metalurgia Universidad Autonotrla de San Luis PotosiAvSierra Leona 550Lomas 2a SeccionSan Luis PotosiS.L.P.78210Mexico Industrial Minera Mexico S.A.de C.V. San Luis PotosiS.L.P.Mexico Centro Universitario de Ciencias Exactas e Ingenierias Universidad de GuadalajaraGuadalajaraJaliscoMexico

Comparative voltammetry and differential double-layer capacitance studies were performed to evaluate interfacial interactions between cnalcopyrite（CuFeS2） and n-isopropyl xanthate（X） in the presence of ammonium bisulfite/39wt%SO2 and caustic starch at different pH *** spectroscopy,Fourier transform infrared（FtIR） spectroscopy,contact angle measurements,and microflotation tests were used to establish the type and extent of xanthate adsorption as well as the species involved under different mineral surface conditions in this *** results demonstrate that the species that favor a greater hydrophobicity of chalcopyrite are primarily CuX and S^0,whereas oxides and hydroxides of Cu and Fe as well as an excess of starch decrease the hydrophobicity.A conditioning of the mineral surface with ammonium bisulfite/39wt%SO2 at pH 6 promotes the activation of surface and enhances the xanthate ***,this effect is diminished at pH ≥ 8,when an excess of starch is added during the preconditioning step.

关键词： sulfide minerals chalcopyrite xanthates flotation interfacial reactions electrochemistry spectroscopy

Engineering the surface of LiCoO2 electrodes using atomic layer deposition for stable high-voltage lithium ion batteries

在线全文

学校读者我要写书评

暂无评论

nano Research 2017年第11期10卷 3754-3764页

作者： Jin Xie Jie Zhao Yayuan Liu Haotian Wang Chong Liu tong Wu po-Chun Hsu Dingchang Lin Yang Jin Yi Cui Department of materials Science and Engineering Stanford University Stanford CA 94305 USA Department of Applied Physics Stanford University Stanford CA 94305 USA Department of materials Science and Engineering Stanford University Stanford CA 94305 USA Stanford Institute for materials and Energy Sciences SLAC National Accelerator Laboratory Menlo Park CA 94025 USA

Developing advanced technologies to stabilize positive electrodes of lithium ion batteries under high-voltage operation is becoming increasingly important,owing to the potential to achieve substantially enhanced energy density for applications such as portable electronics and electrical ***,we deposited chemically inert and ionically conductive LiAlO2 interfacial layers on LiCoO2 electrodes using the atomic layer deposition *** prolonged cycling at high-voltage,the LiAlO2 coating not only prevented interfacial reactions between the LiCoO2 electrode and electrolyte,as confirmed by electrochemical impedance spectroscopy and Raman characterizations,but also allowed lithium ions to freely diffuse into LiCoO2 without sacrificing the power *** a result,a capacity value close to 200 ma＆#183;h＆#183;g-1 was achieved for the LiCoO2 electrodes with commercial level loading densities,cycled at the cut-off potential of 4.6 V ***＋/Li for 50 stable cycles;this represents a 40% capacity gain,compared with the values obtained for commercial samples cycled at the cut-off potential of 4.2 V ***＋/Li.

关键词： Lithium ion batteries lithium cobalt oxide atomic layer deposition

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

基于转录组学分析辣椒对磷营养逆境的响应

中国农业科学 2024年第14期57卷 2827-2846页

作者：徐明睿王晓娟杨亚莉马越飞刘万茂孙颖宁夏大学农学院

【目的】探究辣椒幼苗在不同梯度磷胁迫下的转录水平及生理响应的变化，分析不同梯度磷胁迫的重要通路，并结合相关生理试验分析辣椒应对磷营养逆境的生理机制，筛选出调控磷营养逆境的转录因子及核心基因，为辣椒选育提供理论基础和基... 详细信息

【目的】探究辣椒幼苗在不同梯度磷胁迫下的转录水平及生理响应的变化，分析不同梯度磷胁迫的重要通路，并结合相关生理试验分析辣椒应对磷营养逆境的生理机制，筛选出调控磷营养逆境的转录因子及核心基因，为辣椒选育提供理论基础和基因资源。【方法】本研究以纯系辣椒ca#8幼苗根系为试验材料，采用霍格兰水培法培养至四叶一心期进行4个不同梯度磷胁迫处理，分别为对照组(CK,200μmol·L-1nH4H2po4)、缺磷胁迫组(DP,0μmol·L-1nH4H2po4)、低磷胁迫组(LP,20μmol·L-1nH4H2po4)和高磷胁迫组(HP,1 000μmol·L-1nH4H2po4)。处理2 d后对辣椒根系进行转录组测序（RnA-Seq），并在处理0、2、4和6 d后测定辣椒根系内源激素和抗氧化酶活性。【结果】与CK组对比，DP、LP、HP组的差异表达基因（DEG）分别为626、107、171个，通过GO、KEGG富集分析和WGCnA分析发现10个与磷信号途径相关的DEG,4个与植物激素信号转导途径相关的DEG,7个与抗氧化酶活性相关的DEG，并进行实时荧光定量（q Rt-PCR）验证了转录组数据的准确性。对辣椒幼苗根系内源激素定量测定发现，随着磷胁迫时间的增加，与CK组对比，DP、LP、HP组幼苗根系内各种生长促进类的植物内源激素如赤霉素（GA）、油菜素内酯（BR）、细胞分裂素（CtK）、吲哚乙酸（IAA）、独脚金内酯（SL）、茉莉酸（JA）含量降低，生长抑制类激素如乙烯（EtH）、脱落酸（ABA）含量上升。其中，缺磷胁迫和低磷胁迫表现最为明显，对幼苗根系生长的抑制程度最大。不同梯度磷胁迫处理能够诱导辣椒组织中超氧化物歧化酶（SOD）、过氧化物酶（poD）、过氧化氢酶（cat）活性升高，胁迫后期SOD活性下降，poD和cat活性趋于稳定。【结论】磷营养逆境下，辣椒通过响应磷信号途径、植物激素信号转导途径及抗氧化酶活性相关的差异表达基因，缓解了磷胁迫对辣椒幼苗生长的影响，增强了辣椒对磷胁迫的耐受性。

关键词：辣椒磷胁迫磷饥饿响应转录组基因挖掘

Embryonic stem cell factors and pancreatic cancer

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2014年第9期20卷 2247-2254页

作者： marta Herreros-Villanueva luis Bujanda Daniel D Billadeau Jin-San Zhang Daniel D Billadeau Jin-San Zhang Division of Oncology Research Schulze Center for Novel Therapeutics Mayo Clinic College of Medicine Rochester MN 55905 United States Department of Gastroenterology Hospital Donostia/Instituto Biodonostia Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd) Universidad del País Vasco UPV/EHU20014 San Sebastián Spain School of Pharmaceutical Sciences Key Laboratory of Biotechnology and Pharmaceutical Engineering Wenzhou Medical University

Pancreatic ductal adenocarcinoma(PDAC),the most common type of pancreatic tumor,is a highly aggressive human cancer with the lowest five-year survival rate of any human maligancy primarily due to its earlymetastasis and lack of response to chemotherapy and *** research suggests that PDAC cells comprise a hierarchy of tumor cells that develop around a population of cancer stem cells(CSCs),a small and distinct population of cancer cells that mediates tumoregenesis,metastasis and resistance to standard ***,CSCs could be a target for more effective treatment ***,pancreatic CSCs are subject to regulation by some of key embryonic stem cell(ESC)transctiption factors abberently expressed in PDAC,such as SOX2,OCt4 and *** transcription factors are important DnA-binding proteins present in both embryonic and adult somatic *** critical role of these factors in reprogramming processes makes them essential not only for embryonic development but also *** we provide an overview of stem cell transcription factors,particularly SOX2,OCt4,and nAnOG,on their expression and function in pancreatic *** contrast to embryonic stem cells,in which OCt4 and SOX2 are tightly regulated and physically interact to regulate a wide spectrum of target genes,de novo SOX2 expression alone in pancreatic cancer cells is sufficient to promote self-renewal,dedifferentiation and imparting stemness characteristics via impacting specific cell cycle regulatory genes and epithelial-mesnechymal transtion driver ***,targeting ESC factors,particularly SOX2,could be a worthy strategy for pancreatic cancer therapy.

关键词： Embryonic stem cells nAnOG SOX2 OCt4 Pluripotency Pancreatic cancer cancer stem cells

Volcanic emissions and atmospheric pollution:A study of nanoparticles

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geoscience Frontiers 2021年第2期12卷 746-755页

作者： Erika M.trejos luis F.O.Silva James C.Hower Eriko M.M.Flores carlos mario González Jorge E.Pachón Beatriz H.Aristizábal Hydraulic Engineering and Environmental Research Group Universidad Nacional de Colombia Sede ManizalesManizalesColombia Department of Civil and Environmental Universidad de la CostaCalle 58#55-66Barranquilla 080002Colombia University of Kentucky Center for Applied Energy Research2540 Research Park DriveLexingtonKY 40511USA Department of Earth&Environmental Sciences University of KentuckyLexingtonKY 40506USA Universidade Federal de Santa maria Santa MariaBrazil Centro Lasallista de Investigación y Modelación Ambiental–CLIma Universidad de La SalleBogotáColombia

the influence of emissions of an active volcano on the composition of nanoparticles and ultrafine road dust was identified in an urban area of the *** many cities are close to active volcanoes,few studies have evaluated their influence in road dust *** quality in urban areas is significantly affected by nonexhaust emissions(*** dust,brake wear,tire wear),however,natural sources such as volcanoes also impact the chemical composition of the *** this study,elements from volcanic emissions such as Si>Al>Fe>ca>K>Mg,and Si-Al with K were identified as complex ***,As,Hg,Cd,Pb,As,H,Cd,Pb,V,and salammoniac were observed in nanoparticles and ultrafine *** composition was detected in the order of quartz>mullite>calcite>kaolinite>illite>goethite>magnetite>zircon>monazite,in addition to salammoniac,a tracer of volcanic *** foregoing analysis reflects the importance of carrying out more studies relating the influence of volcanic emissions in road dust in order to protect human *** road dust load(RD_(10))ranged between 0.8 and 26.8 mg m^(−2)in the city.

关键词： nanoparticles Amorphous phases potential hazardous elements Road dust Volcano zone

Geochemical insights into contribution of petroleum hydrocarbons to the formation of hydrates in the taixinan Basin, the South China Sea

在线全文

学校读者我要写书评

暂无评论

Geoscience Frontiers 2021年第6期12卷 394-403页

作者： Yan Li Yun-Xin Fang Qian-Zhi Zhou Xiang-po Xu Jin-Zhong Liu Guo-Yi Zhou Jiang-Hai Wang Guangdong Provincial Key Laboratory of marine Resources and Coastal Engineering School of Marine SciencesSun Yat-Sen UniversityGuangzhou510006China Guangzhou marine Geological Survey Guangzhou510760China State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou510640China Southern marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519000China

Methane hydrate in the South China Sea (SCS) has extensively been considered to be biogenic on the basis of its δ13C andδD *** previous efforts have greatly been made,the contribution of thermogenic oil/gas has still been *** this study,biomarkers and porewater geochemical parameters in hydrate-free and hydrate-bearing sediments in the taixinan Basin,the SCS have been measured for evaluating the contribution of petroleum hydrocarbons to the formation of hydrate deposits via a comparative study of their source inputs of organic matters,environmental conditions,and microbial *** results reveal the occurrence of C_(14)–C_(16) branched saturated fatty acids (bSFAs) with relatively high concentrations from sulfate-reducing bacteria(SRBs) in hydrate-bearing sediments in comparison with hydrate-free sediments,which is in accord with the positive δ^(13)C values of dissolved inorganic carbon (DIC),increasing methane concentrations,decreasing alkalinity,and concentration fluctuation of ions (Cl^(-),Br^(-),SO_(4)^(2-),ca^(2+),and Mg^(2+)).these data indicate the relatively active microbial activities in hydrate-bearing sediments and coincident variations of environmental *** isotope compositions of b SFAs (-34.0‰to -21.2‰),n-alkanes (-34.5‰to-29.3‰),and methane(-70.7‰to -69.9‰) jointly demonstrate that SRBs might thrive on a different type of organic carbon rather than *** with numerous gas/oil reservoirs and hydrocarbon migration channels in the SCS,the occurrence of unresolved complex mixtures (UCMs),odd-even predominance (OEP) values (about 1.0),and biomarker patterns suggest that petroleum hydrocarbons from deep oil/gas reservoirs are the most probable carbon *** new results provide significant evidence that the deep oil/gas reservoirs may make a contribution to the formation of methane hydrate deposits in the SCS.

关键词： Petroleum hydrocarbons Sulfate-reducing bacteria(SRBs) Biomarkers porewater geochemistry Gas hydrates the South China Sea(SCS)

nanomineralogy of evaporative precipitation of efflorescent compounds from coal mine drainage

在线全文

学校读者我要写书评

暂无评论

Geoscience Frontiers 2021年第6期12卷 404-410页

作者： luis F.O.Silva Diana Pinto Guilherme L.Dotto James C.Hower Department of Civil and Environmental.Universidad de La Costa CUCCalle 58#55–66BarranquillaAtlanticoColombia Universidade Federal de Santa maria–UFSM 1000Roraima Avenue97105–900Santa MariaRSBrazil University of Kentucky Department of Earth&Environmental SciencesLexingtonKY40506USA University of Kentucky Center for Applied Energy Research2540 Research Park DriveLexingtonKY40511USA

Efflorescent nanophases(nPs) are found as a transitory accumulation of potentially hazardous elements(PHEs),particularly in tropical climates. the central objective of this study was to investigate the distribution of PHEs with nPs through the evaporative formation structures(EFS) of enormously PHEs-rich coal-mine drainages(CMD). the EFS were studied in natural coal mine drainage for five months in order to determine their geochemical and ecological structures and to assess their position in the reduction of PHEs in nature. the largest coal-fired power plant in South America, located in south Brazil, is used as an example of such a problem. In this work, a novel methodology for the analysis of PHEs in CMD precipitates is proposed for this affected coal *** analytical method, combining X-Ray Diffraction(XRD) and advanced electron microscopies, shows the importance of nanomineralogy in understanding different circumstances of coal contamination. Several ultrafinenanoparticles(UnPs) were identified in the sampled soils and river sediments together with the PHEs. A decrease in PHEs was identified in association with UnPs. However, further investigations are required with regard to the mobility of PHEs in water, atmosphere, soils, and sediments. the EPS was thoroughly studied, acquiring suitable understanding with investigational facts for ca and Fe-sulphates, pickeringite, and several amorphous phases.

关键词： Coal mine drainage Evaporative precipitation Sediments Water and soil pollution