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磺化甲基酚醛树脂(I)在钻井液中的热稳定性研究
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作者 王友绍 袁月莲 +1 位作者 王果庭 张春光 《莱阳农学院学报》 1996年第2期119-123,共5页
本文用动力学方法研究了磺化甲基酚醛树脂(I)在钻井液中的降解机理,发现其降解机理随温度的变化而不同,在低于180℃时为动力学连续一级降解,在高于210℃时为动力学二级降解,并由红外光谱对其降解机理加以解释,且由计算机... 本文用动力学方法研究了磺化甲基酚醛树脂(I)在钻井液中的降解机理,发现其降解机理随温度的变化而不同,在低于180℃时为动力学连续一级降解,在高于210℃时为动力学二级降解,并由红外光谱对其降解机理加以解释,且由计算机拟合出连续一级动力学失水曲线。 展开更多
关键词 磺化甲 基酚醛树脂 降解动力学 热稳定性
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Graves甲亢合并白细胞减少与甲状腺自身抗体相关性研究 被引量:6
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作者 刘迎见 施秉银 李娟 《山东医药》 CAS 北大核心 2010年第17期58-59,共2页
目的对Graves甲亢合并白细胞减少患者的白细胞与甲状腺自身抗体[甲状腺过氧化酶抗体(TPOAb)、甲状腺球蛋白抗体(TGAb)]进行相关性分析,探讨TPOAb、TGAb与Graves甲亢合并白细胞减少的关系。方法采用放射免疫法检测20例Graves甲亢合并白... 目的对Graves甲亢合并白细胞减少患者的白细胞与甲状腺自身抗体[甲状腺过氧化酶抗体(TPOAb)、甲状腺球蛋白抗体(TGAb)]进行相关性分析,探讨TPOAb、TGAb与Graves甲亢合并白细胞减少的关系。方法采用放射免疫法检测20例Graves甲亢合并白细胞减少患者及20例白细胞正常的Graves甲亢患者的TPOAb、TGAb水平,并将白细胞数与TPOAb、TGAb水平进行相关性分析。结果 Graves甲亢合并白细胞减少患者的TPO-Ab、TGAb水平略高于白细胞正常的Graves甲亢患者,但无统计学差异。线性回归分析显示,Graves甲亢患者的白细胞数与TPOAb、TGAb之间没有相关性。结论 TPOAb、TGAb水平与Graves甲亢并白细胞减少无关。 展开更多
关键词 状腺功能亢进症 白细胞减少 磺化物过氧化物酶 状腺球蛋白
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STUDY ON SYNTHESIS OF p-TOLUIDINE-o-SULFONIC ACID
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作者 张卫江 张雪梅 +2 位作者 郭锦棠 张军保 简春贵 《Transactions of Tianjin University》 EI CAS 2001年第4期277-281,共5页
Synthesis of p toluidine o sulfonic acid from p toluidine by sulfonation in solvent was studied,and effects of various reaction conditions or factors on the reaction were discussed in detail.As a result,the follow... Synthesis of p toluidine o sulfonic acid from p toluidine by sulfonation in solvent was studied,and effects of various reaction conditions or factors on the reaction were discussed in detail.As a result,the following optimum process conditions are presented:50 mL dichlorobenzene,2%~5% oleum,molar ratio of sulfonating agent to p toluidine is 1.10~1.12,oleum is dropped in the reaction system in 10 min or so,sulfate formation time is 2 h,distillation lasts 8 h.Under the above conditions,the purity and the yield of p toluidine o sulfonic acid are better than that of the same product made in Japan. 展开更多
关键词 p toluidine o sulfonic acid SULFONATION p toluidine DICHLOROBENZENE
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Photocatalytic degradation of sulfamethazine by graphitic carbon nitride-modified zinc molybdate:Effects of synthesis method on performance, degradation kinetics,and mechanism 被引量:4
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作者 Jing Zhang Xuhui Mao +1 位作者 Wei Xiao Yanfeng Zhuang 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第12期2009-2020,共12页
In the present study,zinc molybdate(β‐ZnMoO4)and graphitic carbon nitride(g‐C3N4)‐modifiedβ‐ZnMoO4(β‐ZnMoO4/g‐C3N4)were prepared to decontaminate aqueous solutions from the antibiotic sulfamethazine(SMZ).Our ... In the present study,zinc molybdate(β‐ZnMoO4)and graphitic carbon nitride(g‐C3N4)‐modifiedβ‐ZnMoO4(β‐ZnMoO4/g‐C3N4)were prepared to decontaminate aqueous solutions from the antibiotic sulfamethazine(SMZ).Our results revealed that the hydrothermal synthesis method greatly influenced the photocatalytic activity of the resultant catalysts.The pristineβ‐ZnMoO4samples obtained under more intensive synthesis conditions(24h at280°C)showed higher photocatalytic activity than that prepared for12h at180°C(denotedβ‐ZnMoO4‐180).In the case of in situ hydrothermal synthesis ofβ‐ZnMoO4/g‐C3N4,a surface‐modified sample was only obtained under the reaction conditions of180°C for12h.Compared with the sheet‐likeβ‐ZnMoO4‐180sample,theβ‐ZnMoO4‐180/g‐C3N4composite showed enhanced photocatalytic activity for the degradation of SMZ.By contrast,the hydrothermal reaction at280°C caused the gradual decomposition of g‐C3N4.It is believed that the structural incorporation of g‐C3N4intoβ‐ZnMoO4at280°C might disrupt the crystal growth,thereby deteriorating the performance of the composite catalysts formed at this temperature.For the composite catalysts prepared by the ultrasonic method,a remarkable increase in the degradation rate of SMZ was only observed at a high g‐C3N4content of8mol%.The photocatalytic degradation of SMZ byβ‐ZnMoO4‐180/g‐C3N4composite catalysts followed pseudo‐first‐order kinetics.Further study of the photocatalytic mechanism revealed that holes and superoxide radicals were the dominant oxidative species in the photodegradation process.The enhanced photocatalytic performance of the composites was attributed to the higher separation efficiency of the photogenerated electron‐hole pairs at heterogeneous junctions.The degradation intermediates of SMZ were detected by liquid chromatography‐mass spectrometry,from which plausible reaction pathways for the photodegradation of SMZ were proposed.Our results indicated that the synthesis method for g‐C3N4composites should be carefully selected to achieve superior photocatalytic performance. 展开更多
关键词 Zinc molybdate Graphitic carbon nitride PHOTOCATALYSIS SULFAMETHAZINE Water treatment
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Hydrometallurgical process for extracting bismuth from by-product of lead smelting based on methanesulfonic acid system 被引量:3
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作者 Tian-xiang NAN Jian-guang YANG +3 位作者 Chao-bo TANG Wen-chao WANG Wei LONG Ji-yuan YANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第1期319-332,共14页
A new hydrometallurgical process based on the methanesulfonic acid system was proposed to extract the bismuth efficiently from by-products of lead smelting.The bismuth extraction process included electrorefining,oxida... A new hydrometallurgical process based on the methanesulfonic acid system was proposed to extract the bismuth efficiently from by-products of lead smelting.The bismuth extraction process included electrorefining,oxidation leaching,and electrodeposition.The optimum conditions of the bismuth extraction process were determined by a single-factor test.The bismuth plate with a purity of 99.8%was obtained under the optimum conditions.Cyclic voltammetry and linear sweep voltammetry were applied to investigating the cathode reaction mechanism of electrorefining.The results show that lead deposition,bismuth deposition,and hydrogen evolution occur at the cathode,and the reactions of metals deposition are irreversible and diffusion-controlled.In addition,decreasing the temperature and acidity can improve the purity of the cathodic product(lead powder)in the electrorefining process. 展开更多
关键词 BISMUTH hydrometallurgical process methanesulfonic acid system electrochemical mechanism
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Facile Conversion of Alcohols to Olefins by Tosylation and Subsequent SiO_2-promoted β-elimination
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作者 RUAN Xiaohong SONG Gaopeng ZHANG Yichun LI Yingxia 《Journal of Ocean University of China》 SCIE CAS 2007年第2期196-198,共3页
A convenient and effective procedure was developed for the conversion of alcohol to olefin by tosylation and subsequent β-elimination promoted by silica gel in this study. Treatment of the alcohols with p-toluenesulf... A convenient and effective procedure was developed for the conversion of alcohol to olefin by tosylation and subsequent β-elimination promoted by silica gel in this study. Treatment of the alcohols with p-toluenesulfonyl chloride in pyridine at 0℃ af- fords tosylates which undergo β-elimination with silica gel in dichloromethane or chloroform at room temperature, yielding olefins with high productivity. 展开更多
关键词 alcohol TOSYLATION silica gel OLEFIN β-elimination
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Ketalization of Catechol with Carbonyl Compounds Catalyzed by Metal p-Toluenesulfonate as Biphasic Acid Catalyst 被引量:1
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作者 梁学正 高珊 +2 位作者 王雯娟 程文萍 杨建国 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第1期124-127,共4页
Ketalization of catechol was studied with various carbonyl compounds using metal p-toluenesulfonate as biphasic catalysts. The results showed that copper p-toluenesulfonate was the most efficient catalysts for the rea... Ketalization of catechol was studied with various carbonyl compounds using metal p-toluenesulfonate as biphasic catalysts. The results showed that copper p-toluenesulfonate was the most efficient catalysts for the reaction. The advantages of high activity, stability, reusability and low cost for the simple synthetic procedure made the catalyst one of the best choice for the reaction. 展开更多
关键词 synthesis 1 3-benzodioxole biphasic acid catalyst metalp-toluenesulfonate
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Proton-Exchange Sulfonated Poly (ether ether ketone) (SPEEK)/SiOx-S Composite Membranes in Direct Methanol Fuel Cells 被引量:6
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作者 高启君 王宇新 +2 位作者 许莉 卫国强 王志涛 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第2期207-213,共7页
A sulfonated poly(ether ether ketone) (SPEEK) membrane with a fairly high degree of sulfonation (DS) can swell excessively and even dissolve at high temperature. To solve these problems, insolvable functionalize... A sulfonated poly(ether ether ketone) (SPEEK) membrane with a fairly high degree of sulfonation (DS) can swell excessively and even dissolve at high temperature. To solve these problems, insolvable functionalized silica powder with sulfonic acid groups (SiOx-S) was added into the SPEEK matrix (DS = 55.1%) to prepare SPEEK/ SiOx-S composite membranes. The decrease in both the swelling degree and the methanol permeability of the membranes was a dose-dependent result of addition of the SiOx-S powder. Pure SPEEK membrane swelled 52.6% at 80℃, whereas the SPEEK/SiOx-S (15%, by mass) membrane swelled only 27.3% at the same temperature. From room temperature to 80℃, all SPEEK/SPEEK/SiOx-S composite membranes had methanol permeability of about one order of magnitude lower than that ofNafion115. Compared with pure SPEEK membranes, the addition of the SiOx-S powder not only leads to higher proton conductivity, but also increases the dimensional stability at higher temperatures, and greater proton conductivity can be achieved at higher temperature. The SPEEK/SiO4-S (20%, by mass) membrane could withstand temperature up to 145℃, at which in 100% relative humidity (RH) its proton conductivity exceeded slightly that of Nafion 1 15 membrane and reached 0.17 S·cm^-1, while pure SPEEK membrane dissolved at 90℃. The SPEEK/SiOx-S composite membranes are promising for use in direct methanol fuel cells because of their good dimensional stability, high proton conductivity, and low methanol permeability. 展开更多
关键词 sulfonated poly(ether ether ketone) functionalized silica composite membrane direct methanol fuel cell
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Antimicrobial Susceptibilities of Salmonella spp. Isolated from Chicken Meat Samples
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作者 F. Kaynak Onurda B. Er +3 位作者 S. Ozgen B. Demirhan U. Abbasoglu A. Bayhan Oktem 《Journal of Food Science and Engineering》 2011年第2期135-140,共6页
The aim of this study was to determine presence of Salmonella spp. in chicken meat samples collected from Ankara, Turkey and determine the susceptibility of the Salmonella isolates to some antimicrobial agents. For th... The aim of this study was to determine presence of Salmonella spp. in chicken meat samples collected from Ankara, Turkey and determine the susceptibility of the Salmonella isolates to some antimicrobial agents. For this purpose, 127 chicken samples were collected from local markets. Investigation of Salmonella was done according to horizontal method, the guidelines of the method recommended by International Standards Organization (ISO). Antimicrobial susceptibilities of Salmonella spp. was performed with microdilution method according to the guidelines of CLSI M100-SI8. Ampicillin, gentamicin sulphate, ofloxacin, levofloxacin, ciprofloxacin, enrofloxacin, tetracycline, ceftriaxon, amoxicillin/clavulanic acid and trimethoprim/sulfamethoxazole were used in the study. Salmonella spp. was isolated from 5 (3.94%) of the 127 chicken meat samples. Although our findings are not within Turkish Food Codex (TFC) values, lower number of samples that involve Salmonella spp. indicates an improvement in the hygienic conditions in Turkey. Among 5 isolates, one isolate was sensitive to all antimicrobial agents tested. 2 isolates exhibited multidrug resistance. Successfully, all the isolates were sensitive to quinolones as a good result in spite of the reported reduced susceptibility from different regions of the world. However, this study should be improved with more chicken samples and Salmonella spp. isolate numbers to support these results. 展开更多
关键词 SALMONELLA chicken meat SUSCEPTIBILITY ANTIMICROBIAL minimum inhibitory concentration.
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Production of Biodiesel from Sludge Palm Oil by Esterification Process 被引量:2
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作者 A. Hayyan M.Z. Alam +4 位作者 M.E.S. Mirghani N.A. Kabbashi N.I.N.M. Hakimi Y.M. Siran S. Tahiruddin 《Journal of Energy and Power Engineering》 2010年第1期11-17,共7页
Sludge palm oil (SPO) is an attractive feedstock and a significant raw material for biodiesel production. The use of SPO can lower the cost ofbiodiesel production significantly. In this study biodiesel fuel was prod... Sludge palm oil (SPO) is an attractive feedstock and a significant raw material for biodiesel production. The use of SPO can lower the cost ofbiodiesel production significantly. In this study biodiesel fuel was produced from SPO by esterification process using P-toluenesulfonic acid (PTSA) as acid catalyst in different dosages in presence of methanol to convert free fatty acid (FFA) to fatty acid methyl ester (FAME). Batch esterification process of SPO was carried out to study the influence of PTSA dosage (0.25-10% wt/wt), molar ratio of methanol to SPO (6:1-20:1), temperature (40-80 ℃), reaction time (30-120 min). The effects of those parameters on the yield of crude biodiesel and conversion of FFA to FAME were monitored. The optimum condition for batch esterification process was 0.75% wt/wt, 10:1 molar ratio, 60 ℃ temperature and 60 minutes reaction time. 展开更多
关键词 BIODIESEL ESTERIFICATION free fatty acid P-toluenesulfonic acid transesterification.
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Kinetic Rate Constant of Liquid Drainage from Colloidal Gas Aphrons 被引量:3
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作者 罗建洪 李军 +1 位作者 黄平 黄美英 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第6期955-959,共5页
A kinetic model fitted by the empirical equation has been proposed to describe the liquid drainage behavior. Rate constants (kd) of liquid drainage equation could be obtained from the above empirical equation. In th... A kinetic model fitted by the empirical equation has been proposed to describe the liquid drainage behavior. Rate constants (kd) of liquid drainage equation could be obtained from the above empirical equation. In this paper, the stability of the colloidal gas aphrons (CGAs), the effect of concentrations of sodium dodecyl benzene sulphate (SDBS), dodecyl trimethylammonium bromide (HTAB) and polyoxyethylene sorbitol anhydride monolaurate(Tween-20), temperature, stirring speed, stirring time, and various kinds of salts on the kd of liquid drainage are further investigated. The results show that the Arrhenius equation can be successfully used to describe the relation between kd arid absolute temperature (T), and concentrations of surfactants, stirring speed, stirring time and salinities also have great effect on the kd. At last, the CGAs drainage mechanism is explained from analysis of the rate of liquid drainage as a function of time. 展开更多
关键词 colloidal gas aphrons liquid drainage STABILITY rate constants
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Synthesis of 3-O-Benzoyl-1 ,2-O-isopropylidene-a-D-allofuranose and Its Dimesylated Derivative
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作者 张卫红 孟祥启 +1 位作者 冯亚青 刘云华 《Transactions of Tianjin University》 EI CAS 2005年第6期440-445,共6页
Diisopropylidenated α-D-glucofuranose (1) was oxidated with CrO3-pyridine complex. Oxidated product and its hydrate were separated and were reduced together to synthesize diisopropylidenated α-D-allofuranose ( 3... Diisopropylidenated α-D-glucofuranose (1) was oxidated with CrO3-pyridine complex. Oxidated product and its hydrate were separated and were reduced together to synthesize diisopropylidenated α-D-allofuranose ( 3). The yield of 3 increased by 8% than that with only oxidated product as reduction substrate. Benzoylated derivative of 3 was selectively nydrolyzed and dimesylated to synthesize 3-O-benzoyl-1 .2- O- isopropylidene-α-D-allofuranose ( 5 ) and its dimesylated derivative respectively. The overall yield of 5 from 1 was 36%. Each step and final products were analyzed by ^1H-NMR spectra and other methods. The experiments showed that the influence of acetic acid concentration on selective hydrolysis was obvious. The hydrolysis yield was 81.8%. Oxidation. reduction and other procedures were practical and had application potential. 展开更多
关键词 3-O-benzoyl-1. 2-O-isopropylidene-α-D-allofuranose OXIDATION reduction - selective hydrolysis dimesylation
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Highly efficient nickel/phosphine catalyzed cross-couplings of diarylborinic acids with aryl tosylates and sulfamates 被引量:1
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作者 KE HaiHua CHEN XiaoFeng +1 位作者 FENG YuanYuan ZOU Gang 《Science China Chemistry》 SCIE EI CAS 2014年第8期1126-1131,共6页
Highly efficient cross-couplings of diarylborinic acids with aryl tosylates and sulfamates are reported for construction of biaryls using a tri(4-methoxyphenyl)phosphine-supported nickel catalyst system: Ni[P(4-MeOC6H... Highly efficient cross-couplings of diarylborinic acids with aryl tosylates and sulfamates are reported for construction of biaryls using a tri(4-methoxyphenyl)phosphine-supported nickel catalyst system: Ni[P(4-MeOC6H4)3]2Cl2/2P(4-MeOC6H4)3 in the presence of K3PO4·3H2O in toluene. A variety of unsymmetrical biaryls could be obtained in good to excellent yields with1.5–3 mol% or 3–5 mol% catalyst loadings for aryl sulfamates and tosylates, respectively. In sharp contrast to the conventional nickel-catalyzed Suzuki coupling with arylboronic acids, arylsulfamates unexpectedly displayed a higher reactivity than the corresponding tosylates in coupling with diarylborinic acids catalyzed by the nickel/phosphine catalyst system. 展开更多
关键词 NICKEL PHOSPHINE cross-coupling diarylborinic acid aryl tosylate aryl sulfamate
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