检索结果-南通市图书馆

^(11)C-PK11195 plasma metabolization has the same rate in multiple sclerosis patients and healthy controls:a cross-sectional study

引用

Neural Regeneration Research 2021年第12期16卷 2494-2498页

作者： Aline Morais de Souza Milena Sales Pitombeira Larissa Estessi de Souza Fabio Luiz Navarro Marques Carlos Alberto Buchpiguel Caroline Cristiano Real Daniele de Paula Faria Laboratory of Nuclear Medicine(LIM43) Department of Radiology and OncologyFaculdade de Medicina FMUSPUniversidade de Sao PauloSao PauloSPBrazil Department of Neurology Faculdade de Medicina FMUSPUniversidade de Sao PauloSao PauloSPBrazil

^(11)C-PK11195 is a positron emitter tracer used for Positron Emission Tomography(PET)imaging of innate immune cell activation in studies of neuroinflammatory *** the image quantitative analysis,it is necessary to quantify the intact fraction of this tracer in the arterial plasma during imaging acquisition(plasma intact fraction).Due to the complexity and costs involved in this analysis it is important to evaluate the real necessity of individual analysis in each 11C-PK11195 PET imaging *** purpose of this study is to compare 11CPK11195 plasma metabolization rate between healthy controls and multiple sclerosis(MS)patients and evaluate the interference of sex,age,treatment,and disease phenotype in the tracer intact fraction measured in arterial plasma samples.11C-PK11195 metabolization rate in arterial plasma was quantified by high performance liquid chromatography in samples from MS patients(n=50)and healthy controls(n=23)at 20,45,and 60 minutes after 11C-PK11195 *** were also stratified by sex,age,treatment type,and MS *** results showed no significant differences in the metabolization rate of healthy controls and MS patients,or in the stratified *** conclusion,11C-PK11195 metabolization has the same rate in patients with MS and healthy controls,which is not affected by sex,age,treatment,and disease ***,these findings could contribute to exempting the necessity for tracer metabolization determination in all 11C-PK11195 PET imaging acquisition,by using a population metabolization rate *** study procedures were approved by the Ethics Committee for Research Projects Analysis of the Hospital das Clinicas of the University of Sao Paulo Medical School(approval No.624.065)on April 23,2014.

关键词： ^(11)C-PK11195 HPLC kinetic modeling metabolization multiple sclerosis neuroinflammation PET imaging PET tracer radiometabolites

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Experimental and numerical analyses of nitrogen oxides formation in a high ammonia‑low hydrogen blend using a tangential swirl burner

引用

碳中和(英文) 2022年第1期1卷 291-310页

作者： A.Alnasif S.Mashruk M.Kovaleva P.Wang A.Valera-Medina College of Physical Sciences and Engineering Queen’s BuildingCardiff UniversityCardiffWales CF243AAUK Engineering Technical College of Al-Najaf Al-Furat Al-Awsat Technical UniversityNajaf 31001Iraq Institute for Energy Research Jiangsu UniversityJiangsu 212013China

Ammonia has been considered as a novel fuel for decarbonization ***,emissions from combustion systems are still posing a ***,experimental and numerical simulations have been conducted to study the concentration of exhaust emissions(Nitric oxide“NO”,Nitrous oxide“N_(2)O”)from burning the ammonia/hydrogen(NH_(3)/H_(2))blend 85/15(vol%).The effects were measured at various thermal powers ranging 10 to 20 kW and with different Reynolds numbers from 20,000—40,*** experimental points were numerically investigated in the Ansys CHEMKIN-Pro environment employing seven chemical kinetic mechanisms taken from the *** experiments have been undertaken at standard atmospheric *** experimental results showed that both NO and N_(2)O gradually increased when the Reynolds number increased from 20,000 to 40,*** with that,the concentration of NO emissions at the exhaust reported minimum level when the Re=20,000 due to lower reactivity radical formation,all that led to a deterioration of the flame ***,the integrated radical intensities of NO*,OH*,NH*,and NH_(2)*demonstrate an increasing trend as Re increased from 20,000 to 40,*** terms of thermal power,N_(2)O suffered an abrupt decrease when the thermal power increased up to 15 kW,while the opposite occurs for *** addition,the radicals intensity of OH*,NH*and NH_(2)*figures show an increase in their concentration when the thermal power increased up to 15 kW then decreased with increasing thermal intensity to reach 20 kW,reflecting into increased NO productions and decreased N_(2)O *** numerical analysis showed that Stagni,Bertolino,and Bowen Mei were the most accurate mechanisms as these give a good prediction for NO and N_(2)*** study also showed that the chemical reaction(HNO+O_(2)←→NO+HO_(2))is the main source of NO *** the chemical reaction(NH+NO←→N_(2)O+H)is responsible for the formation of N_(2)O by consuming NO and when there will

关键词： Ammonia N_(2)O NO Chemiluminescence kinetic modeling

来源：

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

Enzyme hydrolyzed bael fruit liquefaction and its kinetic study

引用

Food Bioscience 2022年第3期47卷 1189-1201页

作者： Rishab Dhar Snehasis Chakraborty Food Engineering and Technology Department Institute of Chemical TechnologyMumbaiMatunga (E)Maharashtra400019India

The study aims to explore the mechanism and optimize the process of enzyme hydrolyzed bael fruit(Aegle marmelos)liquefaction using two different enzymes:pectinase and macerozyme r-10(enzyme mixture).A full factorial design was applied for the factors with 0.05–1.5%(w/w)enzyme concentration(EC),30–60℃ temperature,and incubation time of 30–240 min for pectinase and 60–360 min for *** polynomial models were developed,showing R^(2)≥***-objective numeric optimization was followed to maximize the increase in yield,total reducing sugar(TRS),clarity,and minimizing EC,temperature and ***-treated juice extracts were acceptable on the sensory scale with overall acceptability>*** pomace reduction of 58.8%and 78.9%along with rise in mono and disaccharides were observed after treating with pectinase(t=240 min)and macerozyme(t=360 min),respectively at identical 0.775%EC and 45℃ *** the pectinase enzyme,an optimumΔyield of 32.4%was obtained at 0.82%EC,43℃ temperature in 169.4 ***,with the macerozyme,an optimumΔyield of 39.6%was attained at 0.96%EC,45.6°C temperature in 245.9 *** degradation in bael fruit by enzymatic hydrolysis with pectinase(EC=0.01–1.50%,time=2.5–240 min)and macerozyme(EC:0.01–1.50%,time:5–360 min)was studied at their respective optimum *** modified Michaelis-Menten showed a good fit(R 2>0.98)with the non-linear curve fitting *** treatment showed slower enzyme activity with higher substrate degradation but lower nutrient content compared to the pectinase treatment.

关键词： Bael fruit Enzyme hydrolysis Full factorial design Sensory evaluation Optimization kinetic modeling

来源：

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

Arrhenius parameters determination in non-isothermal conditions for mechanically activated Ag_2O-graphite mixture

引用

Transactions of Nonferrous Metals Society of China 2014年第12期24卷 3994-4003页

作者： Seyed Hadi SHAHCHERAGHI Gholam Reza KHAYATI Department of Mineral Processing Engineering Shahid Bahonar University of Kerman Department of Materials Science and Engineering Shahid Bahonar University of Kerman

The non-isothermal kinetics of mechanochemical reduction of Ag2O with graphite was studied by DSC and TGA with a model of fitting Malek approach and a model-free advanced isoconversional method of Vyazovkin. To evaluate the kinetics parameters, Ag2O–graphite mixture of as-received and milled for 2 and 4 h samples were selected. Based on the results obtained by Vyazovkin method calculation, however, the difference between the maximum and minimum values of activation energy is less than 20%-30%of the average activation energy （（99.38±2.36） kJ/mol） and thermal decomposition of mechanically activated Ag2O for 2 h is a multi-step process. Moreover, the thermal decomposition of mechanically activated Ag2O–graphite powder activated for 4 h is a single-step process （the average activation energy=（93.68±2.26） kJ/mol）. The kinetics modeling shows that the complexity of thermal decomposition of as-received Ag2O–graphite mixture is higher than that of the others. While, the autocatalytic tendency of as-received Ag2O–graphite mixture is lower than that of the others.

关键词： mechanical activation Vyazovkin method kinetic modeling Sestak-Berggren model integral master plot method silver oxide

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Reaction pathway and kinetics of CdO nanoparticles prepared from CdCO_3 precursor using thermal decomposition method

引用

Transactions of Nonferrous Metals Society of China 2016年第4期26卷 1138-1145页

作者： Gholam Reza KHAYATI Seyed Hadi SHAHCHERAGHI Vahid LOTFI Esmael DAREZARESHKI Department of Materials Science and Engineering Shahid Bahonar University of KermanP.O.Box No.76135-133KermanIran Department of Advanced Science and Technology Shahid Bahonar University of KermanP.O.Box No.76135-133KermanIran Mineral Industries Research Centre Shahid Bahonar University of KermanP.O.Box No.76135-133KermanIran

The non-isothermal kinetics of CdO nanoparticles prepared from CdCO3 precursor using thermal decomposition method was investigated. A model-fitting Malek approach and a model-free advanced isoconversional method of Vyazovkin were applied to the analysis of the DSC and TGA data. The results showed that CdO nanoparticles prepared from CdCO3 followed an autocatalytic reaction. Sestak–Berggren model could favorably describe the studied reaction process. Moreover, the apparent activation energy of CdCO3 decomposition was calculated to be (119.19±9.97) kJ/mol and the explicit rate equation form of CdCO3 decomposition was established.

关键词： CdCO_3 CdO nanoparticle kinetic modeling thermal decomposition advanced isoconversional method

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Experimental and modeling Study on de-NO_x Characteristics of Selective Non-catalytic Reduction in O_2/CO_2 Atmosphere

引用

Chinese Journal of Chemical Engineering 2014年第8期22卷 943-949页

作者：李辉韩奎华刘洪涛路春美 National Engineering Laboratory for Coal-fired Pollutants Emission Reduction.School of Energy and Power Engineering Shandong University

An experimental study of thermal de-NOx using NH3 as reductant in 02/C02 atmosphere with the effect of S02 and different additives was performed in a drop tube furnace. Results show that the optimum temperature win- dow is 841-1184 ℃, and the optimum reaction temperature is about 900 ℃ with a de-NOx efficiency of 95.4%. A certain amount of S02 has an inhibiting effect on NO reduction. The effect of additives, including Na2C03, C2H5OH and FeCI3, on NO reduction by NH3 is also explored. The addition of Na2CO3 and FeCI3 is useful to widen the tem- perature window and shift the reaction to lower temperature for the efficiency is increased from 30.5% to 74.0% and 67.4% respectively at 800 ℃. Qualitatively, the modeling results using a detailed kinetic modeling mecha- nism represent well most of the process features. The effect of Na2CO3, C2H5OH and FeCI3 addition can be reproduced well by the Na2C03, C2H5OH and Fe（CO）5 sub-mechanism respectively. The reaction mechanism analysis shows that the effects of these additives on NO reduction are achieved mainly by promoting the produc- tion of OH radicals at lower temperature.

关键词： Selective non-catalytic reduction Denitrification Ammonia kinetic modeling 02/CO2 SO2 Additives

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

kinetics analysis of non-isothermal decomposition of Ag_2O-graphite mixture

引用

Transactions of Nonferrous Metals Society of China 2014年第9期24卷 2991-3000页

作者： Seyed Hadi SHAHCHERAGHI Gholam Reza KHAYATI Department of Mineral Processing Engineering Shahid Bahonar University of KermanKerman Iran Department of Materials Science and Engineering Shahid Bahonar University of KermanKerman Iran

The thermal decomposition kinetics of Ag2O-graphite mixture was systematically studied using a differential scanning calorimeter（DSC） in terms of model-fitting Malek approach, integral master plot method and model-free advanced isoconversional method of Vyazovkin. The results showed that the thermal decomposition occurred in two stages. The first step was the decomposition process of Ag2 O to form porous silver particles as a complex process with the participation of at least two mechanisms, and the second step corresponded to the structural change from porous particles to silver bulk crystals as a single-step process.

关键词： Ag2O advanced isoconversional method kinetic modeling Sestak–Berggren model

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Reaction kinetics for synthesis of sec-butyl alcohol catalyzed by acid-functionalized ionic liquid

引用

Chinese Journal of Chemical Engineering 2015年第1期23卷 106-111页

作者：邱挺唐文莉李承港吴承明李玲 College of Chemistry and Chemical Engineering Fuzhou University

The acid-functionalized ionic liquid([HSO3Pmim]HSO4) was synthesized by a two-step method. Nuclear magnetic resonance(NMR) and Fourier transform infrared spectroscopy(FT-IR) show that the synthesis method is feasible and high purity of ionic liquid can be obtained. Using [HSO3Pmim]HSO4as the catalyst, we studied the reaction kinetics of synthesizing sec-butyl alcohol from sec-butyl acetate and methanol by transesterification in a high-pressure batch reactor. The effects of temperature, initial molar ratio of methanol to ester, and catalyst concentration on the conversion of sec-butyl acetate were studied. Based on its possible reaction mechanism, a homogeneous kinetic model was established. The results show that the reaction heat ΔH is 10.94 × 103J·mol-1, so the reaction is an endothermic reaction. The activation energies Ea+and Ea-are 60.38 × 103 and 49.44 × 103J·mol-1,respectively.

关键词： Ionic liquids sec-Butyl alcohol kinetic modeling Transesterification

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Thermal decomposition kinetics of basic carbonate cobalt nanosheets obtained from spent Li-ion batteries:Deconvolution of overlapping complex reactions

引用

Transactions of Nonferrous Metals Society of China 2018年第6期28卷 1265-1274页

作者： Hossein EBRAHIMZADE Gholam Reza KHAYATI Mahin SCHAFFIE Department of Mineral Industries Research Center Shahid Bahonar University of Kerman Department of Materials Science and Engineering Shahid Bahonar University of Kerman Department of Chemical Engineering Shahid Bahonar University of Kerman

A new non-isothermal method of kinetic analysis was employed to investigate the thermal decomposition kinetic modeling of the basic carbonate cobalt nanosheets（n-BCoC） synthesized from spent lithium-ion batteries（LIBs）. Fraser–Suzuki function was applied to deconvoluting overlapping complex processes from the overall differential thermal curves obtained under the linear heating rate conditions, followed by the kinetic analysis of the discrete processes using a new kinetic analysis method. Results showed that the decomposition of n-BCo C in air occurred through two consecutive reactions in the 136-270 ℃ temperature intervals. Decomposition started by hydroxide component（Co（OH）2） decomposition until to 65% and simultaneously carbonate phase decarbonation began. The process was continued by CO2 evolution and finally carbonate cobalt nanosheets have been produced. The reaction mechanism of the whole process can be kinetically characterized by two successive reactions： a phase boundary contracting reaction followed by an Avrami-Erofeev equation. Mechanistic information obtained by the kinetic study was in good agreement with FT-IR（Fourier transform infrared spectroscopy） and SEM（scanning electron microscopy） results.

关键词： kinetic modeling basic carbonate cobalt nanosheets (n-BCoC) overlapping reactions spent lithium-ion battery

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Experimental and Numerical Studies of Paraguayan Chaco Natural Gas in a Counterflow Diffusion Flame

引用

Journal of Mathematics and System Science 2015年第9期5卷 369-375页

作者： Hemando Maldonado Dario Alviso Miguel Mendieta Juan Carlos Rolon Facultad de Ingenieria Universidad Nacional de Asuncion San Lorenzo 2160 Paraguay.

Combustion is a chemical phenomenon in which a multitude of elementary chemical reactions take place, resulting in the overall process of fuel oxidation. Natural gas fuel has been explored for a few decades and extracted for a few years in the region of Paraguayan Chaco, near Bolivia border. Currently, natural gas is not very important in Paraguay＇s energy matrix, however it could be in the near future if higher volumes are extracted and transported to the most populated cities, specially to the capital. In order to improve Paraguayan natural gas combustion performance, an understanding of its fundamental properties and the combustion pathways is required. This study presents new data for Paraguayan Chaco natural gas combustion in a laminar counterflow diffusion flame configuration at atmospheric pressure. Visible chemiluminescence of excited radicals CH＊ and C2^＊ is employed experimentally. 1D numerical simulation was carried out using Paraguayan Chaco natural gas chemical composition and a standard kinetic mechanism, to which we added CH＊ and C] reactions. Typical flame structures resulting from simulation are presented and a validation of the model is realized comparing experimental and numerical CH＊ and C~ radicals profiles.

关键词： Natural gas counterflow diffusion flames numerical simulation kinetic modeling chemiluminescence

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：