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Effects of binder strength and aggregate size on the compressive strength and void ratio of porous concrete 被引量:22
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作者 P. Chindaprasirt S. Hatanaka +2 位作者 N. Mishima Y. Yuasa T. Chareerat 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2009年第6期714-719,共6页
To test the influence of binder strength, porous concretes with 4 binder strengths between 30.0-135.0 MPa and 5 void ratios between 15%-35% were tested. The results indicated that for the same aggregate, the rates of ... To test the influence of binder strength, porous concretes with 4 binder strengths between 30.0-135.0 MPa and 5 void ratios between 15%-35% were tested. The results indicated that for the same aggregate, the rates of strength reduction due to the increases in void ratio were the same for binders with different strengths. To study the influence of aggregate size, 3 single size aggregates with nominal sizes of 5.0, 13.0 and 20.0 mm (Nos. 7, 6 and 5 according to JIS A 5001) were used to make porous concrete. The strengths of porous concrete are found to be dependent on aggregate size. The rate of strength reduction of porous concrete with small aggregate size is found to be higher than that with larger aggregate size. At the same void ratio, the strength of porous concrete with large aggregate is larger than that with small aggregate. The general equations for porous concrete are related to compressive strength and void ratio for different binder strengths and aggregate sizes. 展开更多
关键词 cement paste porous concrete compressive strength void ratio
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The protection of Thymus vulgaris leaves alcoholic extract against hepatotoxicity of alcohol in rats 被引量:8
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作者 Samah A.El-Newary Nermeen M.Shaffie E.A.Omer 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第4期341-351,共11页
Objective:This study was performed to investigate the protective effect of Thymus vulgaris(T.vulgaris) leaves 70%alcoholic extract against alcohol-mediate hepatotoxicity rats.Methods:The protective effect of extract w... Objective:This study was performed to investigate the protective effect of Thymus vulgaris(T.vulgaris) leaves 70%alcoholic extract against alcohol-mediate hepatotoxicity rats.Methods:The protective effect of extract was investigated at dose of 500 mg/kg/day orally against alcohol-mediate hepatotoxicity using adult male Wister albino rats during 21 days.Protective effect of T.vulgaris extract was evaluated comparing with silymarin standard drug al recommended dose(25 mg/kg/day) orally for 21 days.Results:Alcohol-mediate hepatotoxicity rats(alcohol-control) showed hepatocytes distortion represented as marked increment on liver biomarkers;alkaline phosphatase(ALP),aspartate transaminase(AST) and alanine transaminase(ALT) activities,as well as pronounced reduction on total protein and its fractions albumin and globulin corresponding to normal ranges.Addition to oxidative stress status as depletion on glutathione concentration,catalase(CAT),superoxide dismutase(SOD),glutathione reductase(GR),glutathione-S-transferase(GST) and glutathione peroxidase(GPx)activities,concurrence with augmentation oxidative stress parameters;malondyaldchydc(MDA) and hydrogen peroxide(H_2O_2) concentrations comparing to normal values.Alcohol administration elevated total cholesterol(TC),low density lipoprotein cholesterol(LDL-C) and high density lipoprotein cholesterol(HDL-C) comparing to normal ranges.Co-administration T.vulgaris extract with alcohol showed protective effect on hepatocytes manifested as minimizing on ALP.AST and ALT activities and increment on total protein,albumin and globulin production compared to alcohol-control.Antioxidant enzymes activities;CAT.SOD.GR,GST and GPx were significantly magnified,while MDA and H_2O_2 concentration were lessened corresponding to alcohol-control.Also,lipid profile was markedly improved and risk ratio was lowered compared to alcohol-control.These results were confirmed by normalization of degenerated and fibrotic liver tissue as of alcohol-control.Conclusion:T.vulgaris extract appeared hepatoprotective,hypolipidemic and antioxidant activities on alcohol-mediate hepatotoxicity rats compared to silymarin. 展开更多
关键词 Thymus vulgaris Alcohol-mediate hepatotoxicity POLYPHENOLS Flavonoids Antioxidants enzymes activities Oxidative stress Histopathology
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Adsorbent for Arsenic(V) Removal Synthesized by Radiation-Induced Graft Polymerization onto Nonwoven Cotton Fabric 被引量:1
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作者 Hiroyuki Hoshina Makikatsu Takahashi +1 位作者 Noboru Kasai Noriaki Seko 《International Journal of Organic Chemistry》 2012年第3期173-177,共5页
A fibrous adsorbent for arsenic (As) removal was synthesized with nonwoven cotton fabric as a trunk polymer. 2-hydroxyethyl methacrylate phosphoric acid monomer which composed of phosphoric acid mono (50%) and di (50%... A fibrous adsorbent for arsenic (As) removal was synthesized with nonwoven cotton fabric as a trunk polymer. 2-hydroxyethyl methacrylate phosphoric acid monomer which composed of phosphoric acid mono (50%) and di (50%) ethyl methacrylate ester was introduced with radiation-induced graft polymerization onto nonwoven cotton fabric. The degree of grafting of 130% was obtained at irradiation dose of 20 kGy with 5% of monomer solution for 2 hours reaction time at 40?C reaction temperature. After the grafted material was contacted with 10 mmol/L of zirconium (Zr) solution at pH 1, 0.38 mmol/g of Zr was loaded on phosphoric units as a functional group for As(V) removal. The resulting adsorbent was evaluated by column mode adsorption with 1 mg/L of As(V) solution at various pH with space velocity 200 h–1. The maximum capacity of As(V) adsorption was 0.1 mmol/g at pH 2. 展开更多
关键词 ARSENIC REMOVAL Cotton RADIATION-INDUCED Graft Polymerization Phosphoric Acid ZIRCONIUM
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Synthesis of Highly-Selective Fibrous Adsorbent by Introducing 2-Ethylhexyl Hydrogen-2-Ethylhexylphosphonate for Scandium Adsorption 被引量:1
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作者 Hiroyuki Hoshina Yuji Ueki +1 位作者 Seiichi Saiki Noriaki Seko 《International Journal of Organic Chemistry》 2014年第3期195-200,共6页
2-ethylhexyl hydrogen-2-ethylhexylphosphonate (EHEP) is commonly used as a metal extractant because it has a particular affinity for rare-earth metals like Scandium (Sc). To develop a highly-selective adsorbent of Sc(... 2-ethylhexyl hydrogen-2-ethylhexylphosphonate (EHEP) is commonly used as a metal extractant because it has a particular affinity for rare-earth metals like Scandium (Sc). To develop a highly-selective adsorbent of Sc(III), EHEP was introduced as a functional group onto a polyethylene fabric with radiation-induced graft polymerization(RIGP). The adsorption performances for Sc(III) were evaluated with aqueous solutions containing Sc(III) and Fe(III) in bath and column tests. As a result of column test, the adsorption capacities of Sc(III) and Fe(III) until the bed volume reached 5000 were 5.22 and 0.12 mg/g, respectively. It means that the amount of collected Sc(III) by the EHEP adsorbent was approximately 44 times higher than that of Fe(III). These results indicate that the grafted adsorbent containing EHEP has an extremely high selectivity for Sc(III) adsorption. 展开更多
关键词 FIBROUS ADSORBENT SCANDIUM Radiation-Induced Graft Polymerization SELECTIVE ADSORPTION 2-Ethylhexyl Hydrogen-2-Ethylhexylphosphonate
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Electroconductive Composites Containing Nanocellulose,Nanopolypyrrole,and Silver Nanoparticles
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作者 Samir Kamel Ahmed A.Haroun +1 位作者 Amany M.EI-Nahrawy Mohamed A.Diab 《Journal of Renewable Materials》 SCIE 2019年第2期193-203,共11页
In this work,conducting composites of nanocellulose(NC)/polypyrrole nanoparticles(NPPy)and silver nanoparticles(AgNPs),i.e.,NC/NPPyAg,were synthesized for the first time,to the best of our knowledge,via in situ emulsi... In this work,conducting composites of nanocellulose(NC)/polypyrrole nanoparticles(NPPy)and silver nanoparticles(AgNPs),i.e.,NC/NPPyAg,were synthesized for the first time,to the best of our knowledge,via in situ emulsion polymerization of pyrrole in the presence of surfactant dopants.The AgNPs acted as an oxidizing agent to simultaneously incorporate nanoparticles into the prepared composites.The structures and morphologies of the prepared composites were studied using Fourier transform infrared(FTIR)spectroscopy,X-ray diffraction(XRD),UV-Vis Spectra,thermogravimetric analysis(TGA),and scanning and transmission electron microscopy(SEM and TEM)techniques.Additionally,the prepared composites were characterized by their conductivities,and the dielectric constants(e΄),dielectric losses(e˝),and AC conductivities were studied for the prepared composites with an increasing NPPy content as a function of the frequency. 展开更多
关键词 NANOCELLULOSE nanopolypyrrole emulsion polymerization silver nanoparticles conductive nanocomposites
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Analysis and Evaluation of the Acrylamide Levels in Some Bread Assortments on the Romanian Market by GC-MS/MS
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作者 Mioara Negoita Enuta Iorga +5 位作者 Alina Adascalului Luminita Catana Nastasia Belc Andreea Stan DragosEfstatiade Hassan Y. Aboul-Enein 《Journal of Environmental Science and Engineering(A)》 2016年第4期180-189,共10页
关键词 丙烯酰胺 串联质谱法 气相色谱 罗马尼亚 面包 品种 市场 评价
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Assessment of Patulin Content in Apple Puree and Apple and Fruit Puree by High Performance Liquid Chromatography
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作者 Monica Catana Luminita Catana +5 位作者 Enuta Iorga Mioara Negoita Valentin Ionescu Nastasia Belc Dragos Efstatiade Hassan Y. Aboul-Enein 《Journal of Environmental Science and Engineering(A)》 2016年第7期371-381,共11页
关键词 高效液相色谱法 棒曲霉素 苹果酱 评价 水果 测定 分析样品 原浆
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Synthesis, Spectroscopic Characterization and Thermogravimetric Analysis of Cr(Ⅱ), Cu(Ⅱ), Zn(Ⅱ) and Mg(Ⅱ),Captopril Coordination Compounds
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作者 Asma SAl-Wasidi Nawal MAl-Jafshar +4 位作者 Amal MAl-Anazi Ahmed M.Naglah Robson Fde Farias Claudio Airoldi Moamen SRefat 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2020年第2期661-664,共4页
In this work,we have reported the synthesis and spectroscopic characterization of captopril(Cap)coordination compounds:Cu(Cap)·2H 2O,Cr(Cap)·H 2O,Zn(Cap)·3H 2O and Mg(Cap)4.Herein,it is worthily mention... In this work,we have reported the synthesis and spectroscopic characterization of captopril(Cap)coordination compounds:Cu(Cap)·2H 2O,Cr(Cap)·H 2O,Zn(Cap)·3H 2O and Mg(Cap)4.Herein,it is worthily mentioned that the FTIR spectroscopic technique was employed to recognized the nature of coordination between captopril ligand and copper,chromium,zinc and magnesium(Ⅱ)metal ions.In view of the infrared spectroscopic tool,the copper(Ⅱ)metal ion coordinated toward captopril drug ligand through sulfur atom of SH group dependent on the absent of stretching vibration band of—SH.Based on this result,the stretching motion ofνa(COO)shifts clearly indicates that Cu 2+,Cr 2+,Zn 2+and Mg 2+the carboxylic group is employed as coordinative site for all compounds as a metal-ligand coordinative bond.As a general behavior,it is verified that the coordination compound thermal stability(considering the release of captopril molecules,not the release of water molecules)is affected by the metal cation radius:minor radius is associated with higher thermal stability,probably due to a higher metal-captopril bond dissociation enthalpy. 展开更多
关键词 CAPTOPRIL Transition metals SPECTROSCOPY Coordination compounds THERMOGRAVIMETRY
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Optimization of Grafted Fibrous Polymer as a Solid Basic Catalyst for Biodiesel Fuel Production
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作者 Yuji Ueki Seiichi Saiki +3 位作者 Takuya Shibata Hiroyuki Hoshina Noboru Kasai Noriaki Seko 《International Journal of Organic Chemistry》 2014年第2期91-105,共15页
Grafted fibrous polymer with quaternary amine groups could function as a highly-efficient catalyst for biodiesel fuel (BDF) production. In this study, the optimization of grafted fibrous polymer (catalyst) and transes... Grafted fibrous polymer with quaternary amine groups could function as a highly-efficient catalyst for biodiesel fuel (BDF) production. In this study, the optimization of grafted fibrous polymer (catalyst) and transesterification conditions for the effective BDF production was attempted through a batch-wise transesterification of triglyceride (TG) with ethanol (EtOH) in the presence of a cosolvent. Trimethylamine was the optimal quaternary amine group for the grafted fibrous catalyst. The optimal degree of grafting of the grafted fibrous catalyst was greater than 170%. The optimal transesterification conditions were as follows: The optimal molar quantity of quaternary amine groups, transesterification temperature, molar ratio of TG and EtOH, and primary alkyl alcohol were 0.8 mmol, 80°C, 1:200, and 1-pentanol, respectively. The grafted fibrous catalyst could be applied to BDF production using natural oils. Furthermore, the grafted fibrous catalyst could be used repeatedly after regeneration involving three sequential processes, i.e., organic acid, alkali, and alcohol treatments, without any significant loss of catalytic activity. 展开更多
关键词 Biodiesel Fuel TRIGLYCERIDE TRANSESTERIFICATION RADIATION-INDUCED GRAFT Polymerization Grafted POLYMER Heterogeneous Basic Catalysis
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Preparation Characterization and Thermal Behaviour of Carbopol-TiO<sub>2</sub>Nanocomposites
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作者 Samia Chalal Nabila Haddadine +4 位作者 Naima Bouslah Sihem Souilah Ahmed Benaboura Regis Barille A. Haroun 《Open Journal of Organic Polymer Materials》 2014年第3期55-64,共10页
Composites consisting of carbopol (CP) and ceramic titanium dioxide nanoparticles, TiO2 have been investigated. The CP-TiO2, organic-inorganic hybrid composites have been prepared in DMF by heating the mixture with a ... Composites consisting of carbopol (CP) and ceramic titanium dioxide nanoparticles, TiO2 have been investigated. The CP-TiO2, organic-inorganic hybrid composites have been prepared in DMF by heating the mixture with a constant rate of 1。C/min, up to 30。C, 45。C, 60。C, 80。C, 100。C and 120。C. Proprieties such as absorption, structure and external aspect of the obtained materials were investigated by Uv-vis, FTIR, DRX and SEM analyses. The X-ray diffraction patterns confirmed that the TiO2 nanoparticles maintained their original tetragonal anatase-type crystalline structure in the composites. The chemical structure of the obtained materials was determined by ATR-FTIR spectroscopy. The influence of TiO2 nanoparticles on the thermal proprieties of carbopol matrix was investigated using thermo-gravimetric analysis and differential scanning calorimetry. The glass transition temperature (Tg) of the carbopol matrix was considerably increased by the presence of ceramic feller nanoparticles and its thermal stability was significantly improved. Furthermore the water loss which represents 7.56% of the weight loss in pure CP at 100。C was avoided in the CP-TiO2 nanocomposites at this same temperature. This important finding revealed that ceramic fellers blocked the water loss in the modified carbopol nanocomposites, which stayed stable till 200。C. 展开更多
关键词 CARBOPOL TiO2-Fellers NANOCOMPOSITE Thermal Proprieties FT-IR Spectroscopy
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Finding a New Path for the In-Depth Integration of Manufacturing and Services
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作者 DENG Zhou 《China Economic Transition》 2020年第2期112-118,共7页
The integration of manufacturing and services generally occurs towards the middle and later stages of a country’s industrialization.It is also an important direction of future growth for the transformation and develo... The integration of manufacturing and services generally occurs towards the middle and later stages of a country’s industrialization.It is also an important direction of future growth for the transformation and development of the manufacturing and services industries in the new round of technological and industrial revolutions.For China,promoting the in-depth integration of manufacturing and services is both a necessary response to adapting to new changes in the current environment,and also a proactive measure that will promote the high-quality development of the industries.This integration will play a significant role in positively addressing the challenges currently faced by the manufacturing industry。 展开更多
关键词 SERVICES SERVICES INTEGRATION
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