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Modified National Early Warning Score 2, warning system for predicting treatment outcomes in patients with emphysematous pyelonephritis
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作者 Mohammad S Al-Haggar Zahraa A Abdelmoneim 《World Journal of Nephrology》 2025年第3期202-204,共3页
Emphysematous pyelonephritis(EPN)is a severe,a lethal necrotizing upper urinary tract infection,characterized by gas production within the renal pa-renchyma,collecting system,or perinephric tissue.EPN is emerging as a... Emphysematous pyelonephritis(EPN)is a severe,a lethal necrotizing upper urinary tract infection,characterized by gas production within the renal pa-renchyma,collecting system,or perinephric tissue.EPN is emerging as a sig-nificant concern,necessitating early diagnosis,severity assessment,and timely intervention to improve outcomes.This study proposes a modified National Early Warning Score 2(mNEWS 2)to enhance risk stratification and predictive accuracy in EPN management.The mNEWS 2 refines the original NEWS 2 system,which aggregates 6 physiological indicators(body temperature,systolic blood pressure,pulse rate,oxygen saturation,breathing rate,and degree of consciousness),by incorporating weighted risk stratification indices and specific cutoff values derived from clinical observations,statistical modeling,and predictive per-formance analysis.A pilot study identified optimal thresholds,with a score of 15 maximizing predictive performance for mortality risk and intervention needs,validated through receiver operating characteristic curve analysis.So,the mNEWS 2 score represents a significant advancement in EPN management,offering improved risk stratification and treatment outcomes. 展开更多
关键词 modified National Early Warning Score 2 Emphysematous pyelonephritis Warning system PYELONEPHRITIS Emphysematous
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Preparation of Nano-SiO_2/Amino-modified Polysiloxane Hybrid Superhydrophobic Coating and Thermal-stability Characterization 被引量:3
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作者 李金桦 翁睿 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第1期35-39,共5页
We put forward a large-area and cost-effective method to fabricate superhydrophobic coating by introducing in-situ functionalized nano-SiO2 into side-amino modified hydroxy-terminated polydimethylsiloxane (SA-HTPDMS... We put forward a large-area and cost-effective method to fabricate superhydrophobic coating by introducing in-situ functionalized nano-SiO2 into side-amino modified hydroxy-terminated polydimethylsiloxane (SA-HTPDMS) curing system. With the characterization using water contact angle (WCA) tester, Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), atomic force microscopy (AFM) and simultaneous thermal analysis, the as-prepared coating displayed a tremendous WCA of 154.8±1°, sliding angle (SA) about 3.5° and stable self-cleaning property range from -10 to 80 ℃. It was also found that the synergistic effect of surface micro-nano hierarchical structure and chemical hydrophobicity, stability from matrix had made contributions to the superhydrophobicity and excellent heat resistance up to 300 ℃. 展开更多
关键词 nano-sio2 amino-modified polysiloxane THERMAL-STABILITY SUPERHYDROPHOBIC
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Cerium valence state conversion:Fabrication and environmental remediation of modified CeO_(2)materials
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作者 Jia'ao Han Quansheng Liu +3 位作者 Haitao Xu Yang Wu Shukun Le Chengzhang Zhu 《Journal of Rare Earths》 2025年第3期430-440,I0001,共12页
Rare earth elements are highly applicable in photocatalysis due to their partially filled 4f orbitals,existing in electronic structures that facilitate the transfer of electrons during the reaction process.Among these... Rare earth elements are highly applicable in photocatalysis due to their partially filled 4f orbitals,existing in electronic structures that facilitate the transfer of electrons during the reaction process.Among these materials,CeO_(2)has a distinctive external electronic structure(4f^(1)5d^(1)6s^(2)),abundant oxygen vacancies,and strong conversion ability of Ce^(4+)/Ce^(3+),which makes it an attractive candidate in the field of photocatalysis.To broaden its practical applications in the visible region,the drawbacks of a wide band gap and a slow Ce^(4+)/Ce^(3+)cycle have been addressed through the modification of CeO_(2),thereby accelerating light absorption and self-circulation,and enhancing photocatalytic activity.This paper presents a review of the preparation of modified CeO_(2)catalysts and their application in the conversion of cerium valence state in the photocatalytic degradation of pollutants in water.Furthermore,this paper presents a summary of the most recent development and current challenges,as well as prospect for the application of modified CeO_(2)-based materials. 展开更多
关键词 Rare earths modified CeO_(2) Ce^(4+)/Ce^(3+)pairs PHOTOACTIVITY Environmental remediation
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Synthesis of Waterborne Polyurethane Modified by Nano-SiO_2 Silicone and Properties of the WPU Coated RDX 被引量:4
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作者 Li Yang Zhao Tianbo +2 位作者 Qu Xiaoling Ding Hongjing Li Fengyan 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第2期39-45,共7页
A series of nano silica/silicone modified waterborne polyurethane(WPU) have been synthesized from polytetramethylene glycol and isophorone diisocyanate, dihydroxymethyl propionic acid and triethylamine, ethylenediamin... A series of nano silica/silicone modified waterborne polyurethane(WPU) have been synthesized from polytetramethylene glycol and isophorone diisocyanate, dihydroxymethyl propionic acid and triethylamine, ethylenediamine, trimethylolpropane, nano-SiO2 and the silane coupling agent KH550. The effect of the dosage of nano-SiO2 on the WPU-Si membrane and the coated RDX(cyclotrimethylenetrinitramine) particles have been studied in terms of their surface properties, mechanical properties, and thermal stability. The results showed that with the increase of Si content, the stability of the emulsion reduced gradually. The material with more Si content displayed an increased thermodynamic stability, an increased high temperature resistance, an increased tensile strength and a decreased elongation at break. With the increase of Si content, the surface tension of the material decreased, the bibulous rate reduced, and the contact angle increased gradually, so that the surface tension of the polyurethane and RDX are close to each other which could improve the performance of coating. 展开更多
关键词 nano-sio2 organic silicon waterborne polyurethane coating of RDX
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Synthesis of Modified Epoxy Resin Undercoat for Resistor by Nano-SiO_2
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作者 王秀宇 张之圣 +1 位作者 李海燕 胡明 《Transactions of Tianjin University》 EI CAS 2006年第3期193-198,共6页
A kind of undercoat for resistor with high temperature and humidity resistance was obtained by modifying epoxy resin with proper nano-SiO2 added at 80℃. The structure, thermal stability, humidity resistance, and morp... A kind of undercoat for resistor with high temperature and humidity resistance was obtained by modifying epoxy resin with proper nano-SiO2 added at 80℃. The structure, thermal stability, humidity resistance, and morphological characteristics of the modified epoxy resin undercoat were studied by electrical tests, infrared spectra (IR) analysis, and scanning electron microscopy (SEM). The results show that more compact and steady inter-crosslinked network structures are formed in the modified epoxy resin undercoat added with nano-SiO2, which greatly improves the performance of modified epoxy resin undercoat. The undercoat with nano-SiO2 of about 2. 71%, kept for six months at room temperature without flocculating and aggregating, is of good stability, and the surface of painted resistor is uniform, tight and without air holes on it. The varying ratio of resistance with such undercoat painted is less than one in a thousand after high temperature and humidity resistance tests. 展开更多
关键词 epoxy resin nano-sio2 undercoat high temperature and humidity resistance
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Novel Method of Hyperbranched Polymer Modified Nano-SiO_2-Grafting Hyperbranched Poly(amide-ester) from Nano-SiO_2 by One-Step Polycondensation
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作者 赵辉 李杰 +1 位作者 孙瑞敏 罗运军 《Journal of Beijing Institute of Technology》 EI CAS 2008年第1期100-103,共4页
A new method of surface chemical modification of nano-SiO2 is proposed in this paper. In the presence of catalyst, the active hydroxyl groups on the surface of nano-SiO2 reacted with AB2-type monomer (N, N-dihydroxye... A new method of surface chemical modification of nano-SiO2 is proposed in this paper. In the presence of catalyst, the active hydroxyl groups on the surface of nano-SiO2 reacted with AB2-type monomer (N, N-dihydroxyethyl-3-amino methyl propionate) by one-step polycondensation. And the product's Fourer transform infrared (FTIR) graphs and transmission electron microscopy(TEM) images proved that hyperbranched poly (amine-ester) was grafted on nano-SiO2 surface successfully. Results show that the modified nano-SiO2 exhibits excellent dispersion and stability in some solvents such as alcohol and chloroform. 展开更多
关键词 nano-sio2 hyperbranched poly (amide-ester) one-step polycondensation dispersion and stability
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Joining of SiO2 ceramic and TC4 alloy by nanoparticles modified brazing filler metal 被引量:13
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作者 Hong BIAN Yanyu SONG +3 位作者 Duo LIU Yuzhen LEI Xiaoguo SONG Jian CAO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第1期383-390,共8页
Nano-Al2O3 particles modified Ag Cu Ni filler was adopted to braze the SiO2 ceramic and TC4.The effects of filler size as well as the brazing temperature on the interfacial microstructure and mechanical property of th... Nano-Al2O3 particles modified Ag Cu Ni filler was adopted to braze the SiO2 ceramic and TC4.The effects of filler size as well as the brazing temperature on the interfacial microstructure and mechanical property of the joints were investigated.Nanoscale filler reduced the phases dimension and promoted the homogeneous distribution of microstructure,obtaining a higher joint strength when compared to microscale filler.The increase of brazing temperature made the accelerating dissolution and diffusion of Ti,which promoted the increase of thickness of Ti4O7+TiSi2 layer adjacent to SiO2 ceramic and diffusion layer zone nearby TC4 alloy.The hypoeutectic structure was produced in the brazing seam due to the high Ti content.The maximum shear strength of^40 MPa was obtained at 950°C for 10 min. 展开更多
关键词 BRAZING Microstructure NANOPARTICLES modified filler SIO2 CERAMIC TC4
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Calculation of circulation in the South China Sea during summer of 2000 by the modified inverse method 被引量:8
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作者 YUANYaochu LIUYonggang +3 位作者 LIAOGuanghong LOURuyun SUJilan WANGKangshan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第1期14-30,共17页
On the basis of hydrographic data obtained in August 2000 cruise, the circulation in the South China Sea (SCS) is computed by the modified inverse method in combination with SSH data from TOPEX/ERS-2 analysis. For stu... On the basis of hydrographic data obtained in August 2000 cruise, the circulation in the South China Sea (SCS) is computed by the modified inverse method in combination with SSH data from TOPEX/ERS-2 analysis. For study of the dynamical mechanism, which causes the pattern of summer circulation in the SCS, the diagnostic model (Yuan et al. 1982. Acta Oceanologica Sinica,4(1):1-11; Yuan and Su. 1992. Numerical Computation of Physical Oceanography.474-542) is used to simulate numerically the summer circulation in the SCS. The following results have been obtained. (1) The central and southwestern SCSs are dominated mainly by anticy-clonic circulation systems. They are mainly as follows. 1) There is strong anticyclonic eddy southeast of Vietnam (W1). Its horizontal scale is about 300 km, and it extends vertically from the surface to the about 1 000 m level. 2) There are a warm eddy W2 southeast of Zhongsha Islands and the anticyclonic circulation system W3 west off the Luzon Island. 3) There is a stronger cyclonic eddy C1 between the anticyclonic eddies W1 and W2.4) A strong northward coastal jet is present near the coast of Vietnam, and separates from the coast of Vietnam at about 12° N to the northeast.(2)The northern SCS is dominated mainly by a cyclonic circulation system. There is a cyclonic circulation system near and north of Section N2. (3) The southeastern SCS is dominated mainly by the cyclonic circulation system. (4) Comparing the results of circulation in the SCS during the summer of 2000 with those during the summer of 1998, it is found that they agree qualitatively, but there is the some difference between them in quantity.This shows that the circulation in the SCS has obviously seasonal feature. (5) The dynamical mechanism which products the basic pattern of summer circulation is because the following two reasons: 1) the joint effect of the baroclinity and relief (JEBAR) is essential dynamical cause; and 2) it is next important dynamical cause that the interaction between the wind stress and bottom topography under the southerly monsoon. (6) Comparing the hydrographic structure and distribution of stream functions with the SSH data from TOPEX/ERS-2 analysis in the SCS during August of 2000, they agree qualitatively. 展开更多
关键词 SCS circulation in the summer of 2000 JEBAR interaction between the wind stress and bottom topography SSH data from TOPEX/ERS-2 modified inverse method
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Modified (2+1)-dimensional displacement shallow water wave system and its approximate similarity solutions 被引量:4
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作者 刘萍 付培凯 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期30-36,共7页
Recently, a new (2+1)-dimensional shallow water wave system, the (2+1)-dlmenslonal displacement shallow water wave system (2DDSWWS), was constructed by applying the variational principle of the analytic mechan... Recently, a new (2+1)-dimensional shallow water wave system, the (2+1)-dlmenslonal displacement shallow water wave system (2DDSWWS), was constructed by applying the variational principle of the analytic mechanics in the Lagrange coordinates. The disadvantage is that fluid viscidity is not considered in the 2DDSWWS, which is the same as the famous Kadomtsev-Petviashvili equation and Korteweg-de Vries equation. Applying dimensional analysis, we modify the 2DDSWWS and add the term related to the fluid viscidity to the 2DDSWWS. The approximate similarity solutions of the modified 2DDSWWS (M2DDSWWS) is studied and four similarity solutions are obtained. For the perfect fluids, the coefficient of kinematic viscosity is zero, then the M2DDSWWS will degenerate to the 2DDSWWS. 展开更多
关键词 modified 2+1)-dimensional displacement shallow water wave system viscidity approx-imate similarity solutions Kadomtsev-Petviashvili equation
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Simultaneous removal and oxidation of arsenic from water byδ-MnO 2 modified activated carbon 被引量:7
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作者 Yulong Wang Hupeng Liu +3 位作者 Shaofeng Wang Xuhui Li Xin Wang Yongfeng Jia 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第8期147-160,共14页
The ubiquitous arsenic in groundwater poses a great risk to human health due to its environmental toxicity and carcinogenicity.In the present work,a new adsorbent,δ-MnO2 modified activated carbon,was prepared,and its... The ubiquitous arsenic in groundwater poses a great risk to human health due to its environmental toxicity and carcinogenicity.In the present work,a new adsorbent,δ-MnO2 modified activated carbon,was prepared,and its performance for the uptake of arsenate and arsenite species from aqueous solutions was investigated by batch experiments.Various techniques,including FESEM-EDX,p-XRD,XPS and BET surface area analysis,were employed to characterize the properties of the adsorbent and the arsenic adsorption mechanisms.The results showed thatδ-MnO2 covered on the surface and padded in the pores of the activated carbon.Adsorption kinetic studies revealed that approximately 90.1%and 76.8%of As(Ⅲ)and As(V),respectively,were removed by the adsorbent in the first 9 hr,and adsorption achieved equilibrium within 48 hr.The maximum adsorption capacities of As(V)and As(Ⅲ)at pH 4.0 calculated from Langmuir adsorption isotherms were 13.30 and 12.56 mg/g,respectively.The effect of pH on As(Ⅴ)and As(Ⅲ)removal was similar,and the removal efficiency significantly reduced with the increase of solution pH.Arsenite oxidation and adsorption kinetics showed that the As(Ⅴ)concentration in solution due to As(Ⅲ)oxidation and reductive dissolution of MnO2 increased rapidly during the first 12 min,and then gradually decreased.Based on the XPS analysis,nearly 93.3%of As(Ⅲ)had been oxidized to As(V)on the adsorbent surface and around 38.9%of Mn(Ⅳ)had been reduced to Mn(Ⅱ)after As(Ⅲ)adsorption.This approach provides a possible method for the purification of arsenic-contaminated groundwater. 展开更多
关键词 δ-MnO 2 modified activated carbon ARSENATE ARSENITE ADSORPTION OXIDATION
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Effects of the Modified Linggui Zhugan Decoction(加味苓桂术甘汤) Combined with Short-term Very Low Calorie Diets on Glycemic Control in Newly Diagnosed Type 2 Diabetics 被引量:14
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作者 陈丁生 柯斌 +5 位作者 黄颖娟 孟君 张俊杰 陈泽雄 MICHALSEN Andreas 秦鉴 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2011年第3期185-188,共4页
Objective:To evaluate the effects of the modified Linggui Zhugan Decoction(加味苓桂术甘汤) combined with short-term very low calorie diets(VLCDs) on glycemic control in newly diagnosed type 2 diabetes mellitus(T2DM) p... Objective:To evaluate the effects of the modified Linggui Zhugan Decoction(加味苓桂术甘汤) combined with short-term very low calorie diets(VLCDs) on glycemic control in newly diagnosed type 2 diabetes mellitus(T2DM) patients.Methods:A total of 20 subjects with newly diagnosed T2DM were treated with the modified Linggui Zhugan Decoction(one-month administration) combined with short-term VLCDs(5 days),and 3-months follow-up.A standard 75-g oral-glucose-tolerance test(OGTT) indexes fasting plasma glucose(FPG),post-prandial 0.5 h and 2 h plasma glucose(P0.5hPG,P2hPG),glycated hemoglobin A1C(GHbA1C),body weight,body mass index(BMI),insulin function,insulin resistance index,incidence of hypoglycemia,and the liver and renal functions were evaluated before and after treatment.Correlations of BMI with insulin function and insulin resistance were also assessed.Results:After the treatment,the patients' plasma glucose decreased steadily,FPG decreased from 5.8±0.9 mmol/L at pre-treatment to 5.0±0.6 mmol/L at 3-months follow-up(P<0.05),and P2hPG decreased from 11.7±3.8 mmol/L at pre-treatment to 6.9±0.9 mmol/L at 3-months follow-up(P<0.01).The level of GHbA1C declined from(6.47±1.24)% at pre-treatment to(6.14±0.99)% at 3-months follow-up(P<0.01).Body weight and BMI also declined significantly.Insulin resistance index was improved obviously and no event of hypoglycemia occurred.Part of the patients companied with fatty liver had a transient increase in hepatic transaminase during the treatment,but it turned to normal after the treatment.Conclusions:The modified Linggui Zhugan Decoction combined with short-term VLCDs can be safely implemented for steady glycemic control in newly diagnosed T2DM patients. 展开更多
关键词 modified Linggui Zhugan Decoction Very Low Calorie Diets Type 2 diabetes Plasma glucose
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Sensitive Voltammetric Determination of Captopril Using a Carbon Paste Electrode Modified with Nano-TiO_2/Ferrocene Carboxylic Acid 被引量:6
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作者 Jahan Bakhsh RAOOF Reza OJANI Mehdi BAGHAYERI 《催化学报》 SCIE EI CAS CSCD 北大核心 2011年第11期1685-1692,共8页
A carbon paste electrode (CPE) modified with ferrocene carboxylic acid (FcCA) and TiO2 nanoparticles was constructed by incorporating TiO2 nanoparticles and ferrocene carboxylic acid into the carbon paste matrix. The ... A carbon paste electrode (CPE) modified with ferrocene carboxylic acid (FcCA) and TiO2 nanoparticles was constructed by incorporating TiO2 nanoparticles and ferrocene carboxylic acid into the carbon paste matrix. The electrochemical behavior of captopril (CAP) at the surface of the modified electrode was investigated using electroanalytical methods. The modified electrode showed excellent electrocatalytic activity for the oxidation of CAP in aqueous solutions at physiological pH values. Cyclic voltammetric curves showed that the oxidation of CAP at the surface of the modified electrode reduced its overpotential by more than 290 mV. The modified electrode was used for detecting captopril using cyclic voltammetry and square wave voltammetry techniques. A calibration curve in the range of 0.03 to 2400 μmol/L was obtained that had a detection limit of 0.0096 μmol/L (3?) under the optimized conditions. The modified electrode was successfully used for the determination of captopril in pharmaceutical and biological samples. 展开更多
关键词 ELECTROCATALYSIS modified electrode NANO-TIO2 ferrocene carboxylic acid captopril cyclic voltammetry
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Nonlocal symmetry and exact solutions of the(2+1)-dimensional modified Bogoyavlenskii–Schiff equation 被引量:3
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作者 黄丽丽 陈勇 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第6期63-70,共8页
In this paper,the truncated Painlev′e analysis,nonlocal symmetry,Bcklund transformation of the(2+1)-dimensional modified Bogoyavlenskii–Schiff equation are presented.Then the nonlocal symmetry is localized to the... In this paper,the truncated Painlev′e analysis,nonlocal symmetry,Bcklund transformation of the(2+1)-dimensional modified Bogoyavlenskii–Schiff equation are presented.Then the nonlocal symmetry is localized to the corresponding nonlocal group by the prolonged system.In addition,the(2+1)-dimensional modified Bogoyavlenskii–Schiff is proved consistent Riccati expansion(CRE) solvable.As a result,the soliton–cnoidal wave interaction solutions of the equation are explicitly given,which are difficult to find by other traditional methods.Moreover figures are given out to show the properties of the explicit analytic interaction solutions. 展开更多
关键词 2+1)-dimensional modified Bogoyavlenskii–Schiff equation nonlocal symmetry consistent Riccati expansion soliton–cnoidal wave solution
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Preparation and photocatalytic activity of laponite pillared by CeO_2 modified TiO_2 被引量:4
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作者 林英光 皮丕辉 +2 位作者 郑大锋 杨卓如 王炼石 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第5期732-736,共5页
The laponite pillared by the CeO2 modified TiO2 (Ce-Ti-lap) were prepared by microwave intercalation reaction with laponite as the layered clay, tetrabutyl titanate and cerium chloride as the Ce-Ti composite pillaring... The laponite pillared by the CeO2 modified TiO2 (Ce-Ti-lap) were prepared by microwave intercalation reaction with laponite as the layered clay, tetrabutyl titanate and cerium chloride as the Ce-Ti composite pillaring agent, and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Brumauer-Emmett-Teller (BET) surface area. The photocatalytic activities of Ce-Ti-lap were investigated by the degradation of methyl orange (MO). The results showed that Ce and Ti could be introduced to... 展开更多
关键词 CeO2 modified TiO2 pillared laponite photocatalytic activity microwave intercalation reaction rare earths
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Recovery of iron from copper slag via modified roasting in CO-CO2 mixed gas and magnetic separation 被引量:5
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作者 Ping-guo Jiang Jin-sheng Liu +2 位作者 Yi-yu Xiao Xiao-heng Tan Wen-jie Liu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2020年第7期796-806,共11页
A novel technology,modified roasting in CO-CO2 mixed gas and magnetic separation,was presented to recover iron from copper slag.The effects of various parameters such as dosage of flux(CaO),gas flowrate of CO and CO2,... A novel technology,modified roasting in CO-CO2 mixed gas and magnetic separation,was presented to recover iron from copper slag.The effects of various parameters such as dosage of flux(CaO),gas flowrate of CO and CO2,roasting temperature,roasting time,particle size of modified slag and magnetic flux density on the oxidized modification and magnetic separation were investigated by comparison of the X-ray diffraction patterns and iron recovery ratio.The optimum conditions for recovering iron by oxidizing roasting and magnetic separation are as follows:calcium oxide content of 25 wt.%,mixed gas flow rates of CO2 and CO of 180 and 20 mL/min,oxidizing roasting at 1323 K for 2 h,grinding the modified slag to 38.5-25.0μm and magnetic separation at 170 mT.The mineralogical and microstructural characteristics of modified slag revealed that the iron-bearing minerals in the copper slag were oxidized,the generated magnetite grew into large particles,and the silicate in copper slag was combined with calcium oxide to form calcium silicate.Finally,the iron-bearing concentrate with an iron grade of 54.79%and iron recovery ratio of 80.14%was effectively obtained. 展开更多
关键词 Copper slag CO-CO2 mixed gas modified roasting Magnetic separation Iron recovery ratio
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Preparation of the Ag_2O_2-PbO_2 Modified Electrode and Its Application towards Escherichia coli Fast Counting in Water 被引量:3
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作者 JingGU WenZHANG +3 位作者 YuFengYANG LeiZHENG ZiRongWU LiTongJIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第5期635-638,共4页
A novel nano crystalline Ag2O2-PbO2 film chemically modified electrode (CME) was prepared and the CME was characterized by X-ray diffractometer (XRD) and atomic force microscope (AFM). By chronoamperometry, the nano A... A novel nano crystalline Ag2O2-PbO2 film chemically modified electrode (CME) was prepared and the CME was characterized by X-ray diffractometer (XRD) and atomic force microscope (AFM). By chronoamperometry, the nano Ag2O2-PbO2 CME was used as bioelectro- chemical sensor to determine the population of Escherichia coli (E. coli) in water. Compared with conventional methods, it is found that the technique we used is fast and convenient in counting E. coli. 展开更多
关键词 Ag2O2-PbO2 modified platinum electrode Escherichia coli fast counting.
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Electrochemical determination of vitamin C in the presence of uric acid by a novel TiO_2 nanoparticles modified carbon paste electrode 被引量:4
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作者 Mohammad Mazloum-Ardakani Mohammad Ali Sheikh-Mohseni +2 位作者 Hadi Beitollahi Ali Benvidi Hossein Naeimi 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第12期1471-1474,共4页
The electrochemical behavior of vitamin C(ascorbic acid or AA) is investigated on the surface of a carbon-paste electrode modified with TiO2 nanoparticles and 2,2'-(1,2 butanediylbis(nitriloethylidyne))-bis-hyd... The electrochemical behavior of vitamin C(ascorbic acid or AA) is investigated on the surface of a carbon-paste electrode modified with TiO2 nanoparticles and 2,2'-(1,2 butanediylbis(nitriloethylidyne))-bis-hydroquinone(BBNBH).The prepared modified electrode showed an efficient catalytic role in the electrochemical oxidation of AA,leading to remarkable decrease in oxidation overpotential and enhancement of the kinetics of the electrode reaction.This modified electrode exhibits well-separated oxidation peaks for AA and uric acid(UA).The modified electrode is successfully applied for the accurate determination of AA in pharmaceutical preparations. 展开更多
关键词 Ascorbic acid Uric acid TiO2 nanoparticles ELECTROCATALYSIS modified carbon paste electrode
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Catalytic Oxidation of Dimethyl Ether to Dimethoxymethane over Cs Modified H_3PW_(12)O_(40)/SiO_2 Catalysts 被引量:8
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作者 Qingde Zhang Yisheng Tan +3 位作者 Caihong Yang Yizhuo Han Jun Shamoto Noritatsu Tsubaki 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第3期322-325,共4页
The attractive utilization route for one-step catalytic oxidation of dimethyl ether to dimethoxymethane was successfully carried out over the H3PW12O40(40%)/SiO2 catalyst, modified by Cs, K, Ni, and V. The Cs modifi... The attractive utilization route for one-step catalytic oxidation of dimethyl ether to dimethoxymethane was successfully carried out over the H3PW12O40(40%)/SiO2 catalyst, modified by Cs, K, Ni, and V. The Cs modification of H3PW12O40(40%)/SiO2 gave the most promising result of 20% dimethyl ether conversion and 34.8% dimethoxymethane selectivity. Dimethoxymethane could be synthe- sized via methoxy groups decomposed from dimethyl ether through the synergistic effect between the acid sites and the redox sites of Cs modified H3PW12O40(40%)/SiO2. 展开更多
关键词 dimethyl ether DIMETHOXYMETHANE catalytic oxidation Cs modified H3PW12O40/SiO2 XRD
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Effects of precursor moisture and inert N_2 atmosphere calcinations on structure and properties of alumina modified CeZrLaNd mixed oxides 被引量:3
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作者 Meisheng Cui Zhizhe Zhai +3 位作者 Hao Wang Yongke Hou Yongqi Zhang Xiaowei Huang 《Journal of Rare Earths》 SCIE EI CAS CSCD 2019年第6期609-616,共8页
CeO_2-ZrO_2 mixed oxides are widely used in the three-way catalysts due to their unique reversible oxygen storage and release capacity. Large surface area, high oxygen storage capacity and good thermal stability of ce... CeO_2-ZrO_2 mixed oxides are widely used in the three-way catalysts due to their unique reversible oxygen storage and release capacity. Large surface area, high oxygen storage capacity and good thermal stability of cerium zirconium mixed oxides are the key properties for the automotive catalysts so as to meet the strict emission regulations. In this work, alumina modified CeZrLaNd mixed oxides were prepared by a co-precipitation method. The effects of moisture in precursor and inert N2 atmosphere during calcinations on the structure and properties were investigated by Brunauer-Emmett-Teller(BET) surface area measurements, X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), hydrogen temperature-programmed reduction(H_2-TPR), oxygen storage capacity(OSC), Raman spectroscopy, and X-ray photoelectron spectroscopy(XPS). The results show that the moisture in precursor during calcinations increases the crystal grain size of the cerium zirconium mixed oxides, improving the thermal stability. And the aged surface area of sample after being calcined at1000 ℃ for 4 h reaches 68.8 m^2/g(5.7% increase compared with the common sample). The inert N2 atmosphere endows a great pore-enlarging effect, which leads to high fresh surface area of 148.9 m2/g(13.5% increase compared with the common sample) and big pore volume of 0.5705 mL/g. The redox and oxygen storage capacity are also improved by inert N2 atmosphere with high OSC value of 241.06μmolO_2/g(41.3% increase compared with the common calcination), due to the abundant formation of the crystal defects and oxygen vacancies. 展开更多
关键词 PRECURSOR MOISTURE Inert N2 ATMOSPHERE CALCINATIONS ALUMINA modified CeZrLaNd mixed oxides Rare earths
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Physicochemical properties of a novel composite polymer electrolyte doped with vinyltrimethoxylsilane-modified nano-La_2O_3 被引量:3
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作者 肖围 李新海 +4 位作者 王志兴 郭华军 王接喜 黄思林 甘雷 《Journal of Rare Earths》 SCIE EI CAS CSCD 2012年第10期1034-1040,共7页
Nano-La2O3 was modified with the vinyltrimethoxylsilane by hydrolysis and a novel poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) based composite polymer electrolyte doped with the modified nano-La2O3... Nano-La2O3 was modified with the vinyltrimethoxylsilane by hydrolysis and a novel poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) based composite polymer electrolyte doped with the modified nano-La2O3 was prepared by phase inversion method. The physicochemical properties were studied by SEM, FT-IR, XRD, TG and electrochemical methods. The results of FT-IR indicated that the nano-La2O3 was successfully modified with vinyltrimethoxylsilane. The XRD analysis showed that the incorporation of modified nano-La2O3 into the polymer electrolyte membranes could effectively reduce the crystallinity of PVDF-HFP, and the characterizations also suggested that thermal stability and electrochemical stability window could reach to 382°C and 5.1V, respectively; the reciprocal temperature dependence of ionic conductivity followed Vogel-Tamman-Fulcher (VTF) relation, ionic conductivity at room temperature was up to 3.5×10-3S/cm and lithium ions transference number was up to 0.42; the interfacial resistance increased at initial value about353Ω/cm2 and reached a steady value about 559Ω/cm2 after 5d storage at 30°C. The fabricated Li/As-prepared electrolytes/LiCoO2 coin cell showed excellent rate and cycle performances. 展开更多
关键词 composite polymer electrolyte vinyltrimethoxylsilane modify nano-La2O3 rare earths
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