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Inhibition of EGFR Suppresses Ethyl Alcohol and Tobacco Cell Effects on Growth of Human Oral Keratinocytes and Human Papillomavirus 16 Entry as a Function of Furin
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作者 Joel L. Schwartz Alexander Munaretto +2 位作者 Sirlata Bagchi David Crowe Gonzalo Izaguirre 《Journal of Cancer Therapy》 2015年第1期90-108,共19页
Background: Reported are increased risks for malignant transformation in human oral keratinocytes (HOK) from ethyl alcohol (ETOH), tobacco products or human papilloma virus oncogenic subtype 16 (HPV 16) infections. We... Background: Reported are increased risks for malignant transformation in human oral keratinocytes (HOK) from ethyl alcohol (ETOH), tobacco products or human papilloma virus oncogenic subtype 16 (HPV 16) infections. We examined various HOK cell responses to these factors to show inhibitors of epidermal growth factor receptor (EGFR) also inhibits furin;proprotein convertase (FC) and HPV 16 entry in HOK. Methods: Immortalized HOK by HPV 16 (HPV 16B) or human telomerase (hTERT);primary foreskin keratinocytes (NHFK), primary HOK, buccal keratinocytes (NHBK) and oral SCC-25 were treated with dibenz[a,l]pyrene (DBP), anthraquinone;nitrosamine (NNAL) or ethyl alcohol (ETOH) and acetaldehyde (AA). ETOH was tested for synthesis of malondialdehyde (MDA) and alcohol dehydrogenase expression (ADH). ETOH, and PAH were evaluated by Western immunoblot for oncogene changes, and phosphorylated EGFR expression. Inhibition of EGFR by WZ4002 and Erlotinib and/or carcinogens effect on HPV 16 entry were studied. A green fluorescent pseudovirus (PsV);chloromethylketone (CMK) an inhibitor of furin activity and Western immunoblot of furin cell distribution further characterized HPV 16 entry. Results: ETOH (10 μM) increased expression of phosphorylated EGFR and HPV 16 entry through furin activity, and membrane, nuclear and cytoskeletal accumulations. CMK suppressed HPV 16 entry and blockage of ADH while aldehyde dehydrogenase (ALDH) enhanced HPV 16 entry. Similarly PAH, DBP (4-8 nM), anthraquinone (98 nM) and NNAL (6.9 μM) enhanced HPV 16 entry through furin activity and membrane, nuclear and cytoskeletal accumulations. Furthermore, WZ4002 and Erlotinib suppressed expressions of phosphorylated EGFR, FC activity, and HPV 16 entry. ETOH and DBP treatments also enhanced expressions of protease activated receptor-1 (PAR-1), and p21waf1 while depressed p16 and p27KIP1 expressions in HOK/HPV 16B cells. Conclusion: EGFR inhibitors are candidates for suppression of alcohol and tobacco effects on EGFR phosphorylated expression;keratinocyte growth, and HPV 16 entry and prevention treatment for HPV related diseases. 展开更多
关键词 ethyl Alcohol Tobacco Poly-Cyclic Aromatic Hydrocarbons Nitrosamines DNA Damage Tumor Suppressor Oncogene HPV 16 FURIN PROPROTEIN CONVERTASE EGFR INHIBITORS Phospho-L-Tyrosine INHIBITORS
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Ethyl acetate fraction of Sargassum pallidum extract attenuates particulate matter-induced oxidative stress and inflammation in keratinocytes and zebrafish 被引量:1
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作者 Wook Chul Kim Ji-Won Park +3 位作者 Bohyun Yun WonWoo Lee Kyung-Min Choi Seung-Hong Lee 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第4期137-146,共10页
Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCa... Objective:To evaluate the effect of the ethyl acetate fraction derived from Sargassum pallidum extract against particulate matter(PM)-induced oxidative stress and inflammation in HaCaT cells and zebrafish.Methods:HaCaT cells and zebrafish were used to evaluate the protective effects of the ethyl acetate fraction of Sargassum pallidum extract against PM-induced oxidative stress and inflammation.The production of nitric oxide(NO),intracellular ROS,prostaglandin E_(2)(PGE_(2)),and pro-inflammatory cytokines,and the expression levels of COX-2,iNOS,and NF-κB were evaluated in PM-induced HaCaT cells.Furthermore,the levels of ROS,NO,and lipid peroxidation were assessed in the PM-exposed zebrafish model.Results:The ethyl acetate fraction of Sargassum pallidum extract significantly decreased the production of NO,intracellular ROS,and PGE_(2) in PM-induced HaCaT cells.In addition,the fraction markedly suppressed the levels of pro-inflammatory cytokines and inhibited the expression levels of COX-2,iNOS,and NF-κB.Furthermore,it displayed remarkable protective effects against PM-induced inflammatory response and oxidative stress,represented by the reduction of NO,ROS,and lipid peroxidation in zebrafish.Conclusions:The ethyl acetate fraction of Sargassum pallidum extract exhibits a protective effect against PM-induced oxidative stress and inflammation both in vitro and in vivo and has the potential as a candidate for the development of pharmaceutical and cosmeceutical products. 展开更多
关键词 Particulate matter INFLAMMATION Oxidative stress Sargassum pallidum ethyl acetate fraction ZEBRAFISH
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Swelling Properties of New Hydrogels Based on the Dimethyl Amino Ethyl Acrylate Methyl Chloride Quaternary Salt with Acrylic Acid and 2-Methylene Butane-1,4-Dioic Acid Monomers in Aqueous Solutions
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作者 Issa Katime Eduardo Mendizábal 《Materials Sciences and Applications》 2010年第3期162-167,共6页
Hydrogels of dimethylaminoethyl acrylate methyl chloride quaternary salt (Q9) have been synthesized with different monomer ratio by copolymerization of this poorly studied monomer either with acrylic acid or with 2-me... Hydrogels of dimethylaminoethyl acrylate methyl chloride quaternary salt (Q9) have been synthesized with different monomer ratio by copolymerization of this poorly studied monomer either with acrylic acid or with 2-methylene bu-tane-1,4-dioic acid. Hydrogel swelling was measured as a function of the composition of the hydrogel and of the crosslinking agent ratio. High values of swelling have been obtained at very high crosslinking values (【14 wt %) and the equilibrium swelling was reached at very low time (less than 15 minutes). The swelling isotherms consisted of a steep initial portion and then levelled off as asymptotically to the equilibrium swelling limit. The experimental data suggest clearly that the swelling process obeys second-order kinetics. According to this, the kinetics rate constant and the equilibrium water content were determined at different comonomer composition and crosslinker concentration. The calculated kinetic constants ranged from 0.48 to 3.76 &#215;10-2 min-1 for poly (acrylic acid-co-Q9) hydrogels and from 0.68 to 4.0 &#215;10-2 min-1 for poly (2-methylene butane-1,4-dioic acid-co-Q9) hydrogels depending on the hydrogels composition. The diffusion process was evaluated for each hydrogel showing a non-Fickian type diffusion. In all cases was observed a considerable increase in diffusion coefficient as Q9 content increases. 展开更多
关键词 DIMethyl Amino ethyl Acrylate Methyl Chloride QUATERNARY Salt 2-methylene butane-1 4-Dioic ACID Acrylic ACID SWELLING Diffusion Coefficients Kinetic Order
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甲基丙烯酸N,N-二甲氨基乙酯/丙烯酸N,N-二甲氨基乙酯的可逆加成断裂链转移聚合研究 被引量:10
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作者 辛秀强 王延梅 潘才元 《高分子学报》 SCIE CAS CSCD 北大核心 2005年第3期398-402,共5页
合成了二硫代苯甲酸2- (乙氧基羰基)异丙酯(ECPDB)、二硫代苯甲酸异丙苯酯(CDB)、二硫代苯甲酸1 苯基乙酯(PEDB) 3种二硫代苯甲酸酯链转移剂.以这3种转移剂为基础,用凝胶渗透色谱和核磁共振测试了甲基丙烯酸N ,N 二甲氨基乙酯(DMAEMA)... 合成了二硫代苯甲酸2- (乙氧基羰基)异丙酯(ECPDB)、二硫代苯甲酸异丙苯酯(CDB)、二硫代苯甲酸1 苯基乙酯(PEDB) 3种二硫代苯甲酸酯链转移剂.以这3种转移剂为基础,用凝胶渗透色谱和核磁共振测试了甲基丙烯酸N ,N 二甲氨基乙酯(DMAEMA)和丙烯酸N ,N 二甲氨基乙酯(DMAEA)两种碱性单体的可逆加成断裂链转移(RAFT)聚合的聚合物分子量、分子量分布和结构.发现有的聚合体系聚合物分子量分布较窄,但实验数均分子量与理论数均分子量相差较大;有的体系则转化率很低,聚合物分子量很小.这些可能是由聚合体系中单体活性和链转移剂链转移能力之间的匹配不太协调,使可逆加成断裂链转移快速平衡反应发生偏移或破坏造成的.因此,可通过更换单体或链转移剂来调节这种匹配,从而使可逆加成断裂链转移快速平衡保持稳定,达到聚合更可控,实验分子量与理论分子量更接近,分子量分布更窄的目的. 展开更多
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Syntheses,structures,and properties of three coordination polymers based on 5⁃ethylpyridine⁃2,3⁃dicarboxylic acid and N⁃containing ligands
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作者 TANG Long BIAN Yaxin +3 位作者 CHEN Luyuan HOU Xiangyang WANG Xiao WANG Jijiang 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第10期1975-1985,共11页
Three coordination polymers[Mn(epda)(2,2'⁃bipy)(H_(2)O)](1),[Mn(epda)(phen)](2),and[Co_(2)(epda)2(bpe)2(H_(2)O)_(4)]·5H_(2)O(3)(H2epda=5⁃ethyl⁃pyridine⁃2,3⁃dicarboxylic acid,2,2'⁃bipy=2,2'⁃bipyridine,... Three coordination polymers[Mn(epda)(2,2'⁃bipy)(H_(2)O)](1),[Mn(epda)(phen)](2),and[Co_(2)(epda)2(bpe)2(H_(2)O)_(4)]·5H_(2)O(3)(H2epda=5⁃ethyl⁃pyridine⁃2,3⁃dicarboxylic acid,2,2'⁃bipy=2,2'⁃bipyridine,phen=phenanthroline,bpe=1,2⁃bis(4⁃pyridyl)ethylene)were synthesized by solvothermal reactions and characterized by single⁃crystal X⁃ray diffraction,thermogravimetric analyses,IR spectroscopy and elemental analysis.1 displays a 1D chain struc⁃ture,and these chains are joined by O-H…O hydrogen bonding andπ⁃πstacking interactions to generate a 2D layer structure.2 displays a 2D layer structure,and adjacent layers are generated 3D architecture throughπ⁃πstacking interactions.3 displays a 1D chain structure,and adjacent chains are generated double layer structure through O-H…O hydrogen bonding.The fluorescent properties of 1 and 3 indicate that they can potentially be used as a luminescent sensor.1 was highly selective and sensitive towards o⁃nitrophenol through different detection mechanisms,however,3 was highly selective and sensitive towards 2,4,6⁃trinitrophenol.In addition,the magnetic behavior of 2 has also been investigated.CCDC:2172533,1,2355773,2,2355774,3. 展开更多
关键词 coordination polymers 5⁃ethyl⁃pyridine⁃2 3dicarboxylate ligand crystal structures fluorescent properties magnetic behavior
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The Detection of 1-Palmitoyl-2-oleoyl-<i>sn</i>-glycero-3-phosphoethanol and Ethyl Glucuronide in Human Umbilical Cord
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作者 Joseph Jones Mary Jones +1 位作者 Charles Plate Douglas Lewis 《American Journal of Analytical Chemistry》 2012年第12期800-810,共11页
In utero exposure to ethanol continues to be a significant public health issue and neonatal healthcare professionals are in need of objective means to identify exposed newborns. The aim of this study was to fully vali... In utero exposure to ethanol continues to be a significant public health issue and neonatal healthcare professionals are in need of objective means to identify exposed newborns. The aim of this study was to fully validate two methods for the detection of two direct alcohol biomarkers, 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanol (POPE) and ethyl glucuronide (EtG), in umbilical cord and apply the assays to a group of authentic specimens. The limits of detections were 2 and 1 ng/g for POPE and ETG and the limits of quantitation were 4 and 3 ng/g, respectively. Inter and intra-day precision and accuracy measurements were within 15%. The assays were applied to 308 authentic specimens where we detected POPE in five (1.6%) specimens and EtG in twelve (3.9%) specimens. The mean concentrations were 11.4 ng/g ± 9.4 ng/g and 127.2 ± 227.7 ng/g for POPE and EtG, respectively. This study suggested that umbilical cord was a suitable specimen type for the identification of newborns exposed to ethanol in the womb and the prevalence of POPE and EtG detected in umbilical cord were consistent with the prevalence of self-reported binge drinking reported by the National Birth Defect Prevention Study (NBDPS) and Behavioral Risk Factor Surveillance System (BRFSS). Further studies are required to fully describe the association between the observed concentrations of POPE and EtG in umbilical cord to the level of maternal consumption of ethanol. 展开更多
关键词 PHOSPHATIDYLETHANOL ethyl GLUCURONIDE Umbilical Cord Ethanol FETUS LC-MS/MS Prenatal Exposure Fetal Alcohol Spectrum Disorders FASD
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EMS与NaN_3对甘蓝型油菜和芥菜型油菜诱变的效果 被引量:9
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作者 赵福永 郑娇 +2 位作者 何芳 何文俊 李利露 《江西农业学报》 CAS 2010年第9期6-9,共4页
采用化学诱变剂甲基磺酸乙酯(EMS)和叠氮化钠(NaN3)分别以不同浓度和处理时间组合,对3个甘蓝型油菜品种(湘油15号、中油821、中双9号)和3个芥菜型油菜品种(金油王2号、品系153和154)成熟种子进行诱变。以未处理组为对照,比较了诱变当代(... 采用化学诱变剂甲基磺酸乙酯(EMS)和叠氮化钠(NaN3)分别以不同浓度和处理时间组合,对3个甘蓝型油菜品种(湘油15号、中油821、中双9号)和3个芥菜型油菜品种(金油王2号、品系153和154)成熟种子进行诱变。以未处理组为对照,比较了诱变当代(M1)种子的发芽率和子代(M2)株高、叶色、花色、种皮颜色和花粉育性等生物学性状。结果发现,随着诱变剂浓度的增加和处理时间的延长各品种(系)M1代种子的发芽率逐渐降低,且相同处理条件下芥菜型油菜的平均发芽率要低于甘蓝型油菜;在M2代中初步筛选出28个甘蓝型油菜和38个芥菜型油菜的株高、叶色、花色等性状的突变体,为今后油菜遗传改良和功能基因组学研究提供了更丰富的研究材料。 展开更多
关键词 EMS BRASSICA JUNCEA BRASSICA napus Mutagenic Effect
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Tailoring Ni based catalysts by indium for the dehydrogenative coupling of ethanol into ethyl acetate
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作者 Ming Yin Jifeng Pang +4 位作者 Jin Guo Xianquan Li Yujia Zhao Pengfei Wu Mingyuan Zheng 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第8期1321-1331,共11页
Exploring stable and robust catalysts to replace the current toxic CuCr based catalysts for dehydrogenative coupling of ethanol to ethyl acetate is a challenging but promising task.Herein,novel NiIn based catalysts we... Exploring stable and robust catalysts to replace the current toxic CuCr based catalysts for dehydrogenative coupling of ethanol to ethyl acetate is a challenging but promising task.Herein,novel NiIn based catalysts were developed by tailoring Ni catalysts with Indium(In)for this reaction.Over the optimal Ni0.1Zn0.7Al0.3InOx catalyst,the ethyl acetate selectivity reached 90.1%at 46.2%ethanol conversion under the conditions of 548 K and a weight hourly space velocity of 1.9 h^(-1)in the 370 h time on stream.Moreover,the ethyl acetate productivity surpassed 1.1 g_(ethyl acetate)g_(catalyst)^(-1)h^(-1),,one of the best performance in current works.According to catalyst characterizations and conditional experiments,the active sites for dehydrogenative coupling of ethanol to ethyl acetate were proved to be Ni4In alloys.The presence of In tailored the chemical properties of Ni,and subsequently inhibited the C-C cracking and/or condensation reactions during ethanol conversions.Over Ni4In alloy sites,ethanol was dehydrogenated into acetaldehyde,and then transformed into acetyl species with the removal of H atoms.Finally,the coupling between acetyl species and surface-abundant ethoxyde species into ethyl acetate was achieved,affording a high ethyl acetate selectivity and catalyst stability. 展开更多
关键词 Dehydrogenative coupling ETHANOL ethyl acetate Nickel and indium alloys
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高取代度乙基纤维素的一步法合成机理及研究 被引量:2
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作者 李洪青 邹华生 +2 位作者 肖磊 廖晓燕 刘会冲 《涂料工业》 CAS CSCD 2005年第7期16-20,共5页
采用正交试验方法,以甲苯为稀释剂,探讨了高取代度乙基纤维素一步法合成的反应机理及工艺条件,并采用红外光谱、核磁共振氢谱对产物分子结构进行了鉴定表征。以27g纤维素为基准,优选出一步法合成最佳工艺条件为甲苯用量180g,氢氧化钠溶... 采用正交试验方法,以甲苯为稀释剂,探讨了高取代度乙基纤维素一步法合成的反应机理及工艺条件,并采用红外光谱、核磁共振氢谱对产物分子结构进行了鉴定表征。以27g纤维素为基准,优选出一步法合成最佳工艺条件为甲苯用量180g,氢氧化钠溶液质量浓度60%,氯乙烷用量477.5g,反应温度140℃,反应时间13h,该条件下,乙氧基含量(质量分数)可达44.8%。 展开更多
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High mobility group box 1 in the central nervous system:regeneration hidden beneath inflammation
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作者 Hanki Kim Bum Jun Kim +4 位作者 Seungyon Koh Hyo Jin Cho Xuelian Jin Byung Gon Kim Jun Young Choi 《Neural Regeneration Research》 SCIE CAS 2025年第1期107-115,共9页
High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the ex... High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the extracellular space functions as a pro-inflammatory damage-associated molecular pattern,which has been proven to play an important role in a wide variety of central nervous system disorders such as ischemic stroke,Alzheimer’s disease,frontotemporal dementia,Parkinson’s disease,multiple sclerosis,epilepsy,and traumatic brain injury.Several drugs that inhibit high-mobility group box 1 as a damage-associated molecular pattern,such as glycyrrhizin,ethyl pyruvate,and neutralizing anti-high-mobility group box 1 antibodies,are commonly used to target high-mobility group box 1 activity in central nervous system disorders.Although it is commonly known for its detrimental inflammatory effect,high-mobility group box 1 has also been shown to have beneficial pro-regenerative roles in central nervous system disorders.In this narrative review,we provide a brief summary of the history of high-mobility group box 1 research and its characterization as a damage-associated molecular pattern,its downstream receptors,and intracellular signaling pathways,how high-mobility group box 1 exerts the repair-favoring roles in general and in the central nervous system,and clues on how to differentiate the pro-regenerative from the pro-inflammatory role.Research targeting high-mobility group box 1 in the central nervous system may benefit from differentiating between the two functions rather than overall suppression of high-mobility group box 1. 展开更多
关键词 central nervous system damage-associated molecular pattern ethyl pyruvate glycyrhizzin high mobility group box 1 INFLAMMATION neural stem cells NEURODEVELOPMENT oligodendrocyte progenitor cells redox status REGENERATION
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Waste Management in Propylene Epoxidation Process with the Use of Supercritical Fluid Media 被引量:1
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作者 F. M. Gumerov R. A. Kayumov +3 位作者 R. A. Usmanov A. A. Sagdeev I. Sh. Abdullin R. F. Sharafeev 《American Journal of Analytical Chemistry》 2012年第12期950-957,共8页
Experimental results on solubility of the styrene, phenol, methylphenylcarbinol, acetophenone, ethyl benzene, propylene glycol and molybdenum as a complex with Trilon B in supercritical CO2 obtained using a dynamic (f... Experimental results on solubility of the styrene, phenol, methylphenylcarbinol, acetophenone, ethyl benzene, propylene glycol and molybdenum as a complex with Trilon B in supercritical CO2 obtained using a dynamic (flow) method are presented. The obtained data are described in the framework of Peng-Robinson equation. The results of the experients on the extraction of organic components from waste formed in the olefin epoxidation process at Nizhnekam-skneftekhim Inc., on the analysis of extract composition, and on the testing of the extract as an epoxidation catalyst are presented. The supercritical water oxidation (SCWO) process of epoxidation process waste was conducted in periodical and continuous mode. The analysis results of reaction product are given. Pilot experiments on dry sediment formation were conducted using Radio Frequency (RF) Inductively Coupled Plasma (ICP) of low pressure. 展开更多
关键词 Styrene Phenol Methylphenylcarbinol ACETOPHENONE ethyl Benzene PROPYLENE GLYCOL Molybdenum SUPERCRITICAL Carbon Dioxide SOLUBILITY Dynamic Method Description of SOLUBILITY PengRobinson Equation SUPERCRITICAL Water Oxidation High-Frequency Induction Plasma
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ISOBARIC VAPOR-LIQUID EQUILIBRIUMS OF OCTANE-ETHYL ACETATE AND OCTANE-ISOPROPYL ACETATE SYSTEMS 被引量:2
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作者 陈钟秀 胡望明 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1995年第3期59-65,共7页
The isobaric vapor-liquid equilibrium data of systems of ethyl acetate<sub>(1)</sub>-n-octane<sub>(2)</sub> andisopropyl acetate<sub>(1)</sub>-n-octane<sub>(2)</sub... The isobaric vapor-liquid equilibrium data of systems of ethyl acetate<sub>(1)</sub>-n-octane<sub>(2)</sub> andisopropyl acetate<sub>(1)</sub>-n-octane<sub>(2)</sub> were determined at 0.0709 MPa and 0.1013 MPa by using a modifiedRose-Williams still.The experimental data were tested for thermodynamical consistency and correlatedsatisfactorily with p-T equation of state and Wilson equation. 展开更多
关键词 OCTANE ethyl ACETATE isopropyl ACETATE vapor- liquid equilibrium thermodynamic consistency p-T EQUATION WILSON EQUATION
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3(5)-氨基吡唑-4-甲酸乙酯的合成研究 被引量:5
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作者 蒋华江 孙日勇 蔡继平 《化工时刊》 CAS 2005年第3期12-13,共2页
以乙氧亚甲基氰乙酸乙酯和水合肼为原料 ,考察了溶剂、温度以及原料配比对产率的影响 ,确定了初步的反应条件 ,所得的 3(5 ) -氨基吡唑 - 4 -甲酸乙酯 ,产率达到了 85 % ;并用岛津FTIR— 84 0 0型红外分光光度计和NMR— 5 0 0型核磁共... 以乙氧亚甲基氰乙酸乙酯和水合肼为原料 ,考察了溶剂、温度以及原料配比对产率的影响 ,确定了初步的反应条件 ,所得的 3(5 ) -氨基吡唑 - 4 -甲酸乙酯 ,产率达到了 85 % ;并用岛津FTIR— 84 0 0型红外分光光度计和NMR— 5 0 0型核磁共振仪进行结构表征 ,WATERS— 6 0 0E型HPLC测定含量。本实验具有产率高、溶剂易回收、温度易控制等优点。 展开更多
关键词 500 400 HPLC E
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Ethyl Methane Sulphonate (EMS) Induced Mutagenesis in Malaysian Rice (cv. MR219) for Lethal Dose Determination 被引量:11
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作者 Ali Benjavad Talebi Amin Benjavad Talebi Behzad Shahrokhifar 《American Journal of Plant Sciences》 2012年第12期1661-1665,共5页
Chemical and physical mutagenesis has been used to increase genetic variability in crop plants. More than 430 new varieties have been derived as mutants of rice (Oryza sativa L.) via the application of different mutag... Chemical and physical mutagenesis has been used to increase genetic variability in crop plants. More than 430 new varieties have been derived as mutants of rice (Oryza sativa L.) via the application of different mutagenic agents. Chemical mutagens such as ethyl methane sulphonate (EMS), diepoxybutane-derived (DEB), sodium azide and irradiation (Gamma rays, X-rays and fast neutrons) have been widely used to induce a large number of functional variations in rice and others crops. Among chemical mutagens, the alkylating agent, ethyl methane sulfonate (EMS) is the most commonly used in plants as it causes a high frequency of nucleotide substitutions, as detected in different genomes. In this study, seeds of potential genotype of the popular variety, (Oryza sativa L. spp. Indica cv. MR219) were treated with EMS at concentrations of 0.25%, 0.50%, 0.75%, 1%, 1.25%, 1.5% and 2%. Sensitivity to EMS was determined by various measurements on the M1 generation. As concentration of applied EMS increased, will decrease in germination, seedling height, root length and emergence under field conditions was observed in M1 generation as compared to the non-treatment control. Plant height and root length also decreased with increases in EMS mutagenesis in an approximately linear fashion. The LD25 and LD50 values were observed based on growth reduction of seedlings after EMS treatment with 0.25% and 0.50% on the rice variety (Oryza sativa L. spp. Indica cv. MR219). 展开更多
关键词 EMS LETHAL Dose Chemical Mutagenesis ethyl-Methane SULFONATE Oryza Sativa Indica cv. MR219
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新型钼铋硫化矿捕收剂CYB⁃06的开发及工业应用
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作者 唐雪峰 龙冰 +4 位作者 程征 沈慧明 赵洪冬 刘杰 徐涛 《矿冶工程》 CAS 北大核心 2024年第3期62-64,共3页
针对柿竹园钼铋硫化矿矿石特点,开发了新型环保硫化矿捕收剂CYB⁃06。工业试验结果表明,以CYB⁃06和乙硫氮为组合捕收剂,硫化矿全浮选精矿钼、铋、硫回收率分别为84.12%、67.90%、83.28%,较丁基黄药与乙硫氮组合使用时分别提高了2.32、2.8... 针对柿竹园钼铋硫化矿矿石特点,开发了新型环保硫化矿捕收剂CYB⁃06。工业试验结果表明,以CYB⁃06和乙硫氮为组合捕收剂,硫化矿全浮选精矿钼、铋、硫回收率分别为84.12%、67.90%、83.28%,较丁基黄药与乙硫氮组合使用时分别提高了2.32、2.82、6.55个百分点;浮选尾水COD值117 mg/L,较丁基黄药与乙硫氮组合使用时降低了41.21%。新型捕收剂CYB⁃06无刺激性气味、选别指标良好、尾矿废水COD值低,对矿山企业提质增效、清洁生产和环境保护具有重要意义。 展开更多
关键词 CYB06
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微流控制备包覆含能材料模拟物的核壳结构微球
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作者 刘静 吕英迪 +2 位作者 刘建行 杨文博 陶胜洋 《火炸药学报》 EI CAS CSCD 北大核心 2024年第6期506-512,I0003,共8页
基于简单的生产单重乳液的液滴微流控技术,结合相分离和结晶固化的方法,制备出具有对硝基苯甲醛(p-NBA)核层和聚苯乙烯(PS)壳层的核壳结构微球,一步完成了对高能炸药3,4-二硝基呋咱基氧化呋咱(DNTF)的模拟物p-NBA的包覆;通过调控p-NBA... 基于简单的生产单重乳液的液滴微流控技术,结合相分离和结晶固化的方法,制备出具有对硝基苯甲醛(p-NBA)核层和聚苯乙烯(PS)壳层的核壳结构微球,一步完成了对高能炸药3,4-二硝基呋咱基氧化呋咱(DNTF)的模拟物p-NBA的包覆;通过调控p-NBA、PS以及赋形剂乙基纤维素(EC)的含量配比,可以得到不同结构和形貌的微球,并研究了上述因素对核壳结构微球的影响;基于高能炸药DNTF的包覆钝化效果和包覆量双重条件,在使用大相对分子质量(M r=300000~350000)PS情况下,得出最佳实验条件为:EC和p-NBA质量比为1∶10,PS质量分数为8%。结果表明,赋形剂的添加有助于促进p-NBA的结晶,使其能够在液滴相分离的时候形成球形颗粒,从而被完整包覆;PS在微液滴中的初始质量分数越大,形成的壳层越厚、球形度越高,但封装DNTF的壳层越厚,爆炸威力会降低。 展开更多
关键词 (p-NBA) (EC) DNTF
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固体超强酸SO_4^(2-)/Fe_2O_3的制备及其催化性能的研究 被引量:15
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作者 李建伟 周长智 弓彦忠 《应用化工》 CAS CSCD 2005年第5期313-314,共2页
用(NH4)2SO4·Fe2(SO4)3·24H2O直接焙烧的方法制备了固体超强酸催化剂SO42-/Fe2O3,并以乙酸乙酯的合成反应考察了焙烧温度、焙烧时间对固体酸催化活性的影响。实验表明:最佳焙烧温度为550℃,最佳焙烧时间为4h。当催化剂用量为... 用(NH4)2SO4·Fe2(SO4)3·24H2O直接焙烧的方法制备了固体超强酸催化剂SO42-/Fe2O3,并以乙酸乙酯的合成反应考察了焙烧温度、焙烧时间对固体酸催化活性的影响。实验表明:最佳焙烧温度为550℃,最佳焙烧时间为4h。当催化剂用量为2g,醇酸物质的量比为1.6∶1,回流时间2h时,乙酸转化率为85.1%。 展开更多
关键词 SO4^2-/FE2O3 FE2(SO4)3 (NH4)2SO4
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Liquid Chromatography-Tandem Mass Spectrometry Assay to Detect Ethyl Glucuronide in Human Fingernail: Comparison to Hair and Gender Differences 被引量:1
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作者 Joseph Jones Mary Jones +4 位作者 Charles Plate Douglas Lewis Michael Fendrich Lisa Berger Daniel Fuhrmann 《American Journal of Analytical Chemistry》 2012年第1期83-91,共9页
Over the past decade, the use of hair specimens for the long-term detection of the alcohol biomarker ethyl glucuronide has been increasing in popularity and usage. We evaluated the usefulness of fingernail clippings a... Over the past decade, the use of hair specimens for the long-term detection of the alcohol biomarker ethyl glucuronide has been increasing in popularity and usage. We evaluated the usefulness of fingernail clippings as a suitable alterna-tive to hair for ethyl glucuronide detection. A liquid chromatography-tandem mass spectrometry method for the detection of ethyl glucuronide in fingernail clippings was fully validated and used to analyze the hair and/or fingernail specimens of 606 college-aged study participants. The limit of detection was 2 pg/mg, the limit of quantitation was 8 pg/mg and the method was linear from 8 to 2000 pg/mg. Intra- and inter-assay imprecision studies at three different concentrations (20, 40, 200 pg/mg) were all within 7.8% and all intra- and inter-assay bias studies at these levels were within 115.1% of target concentration. Ethyl glucuronide levels in fingernail (mean = 29.1 ± 55.6 pg/mg) were higher than ethyl glucuronide levels in hair (mean = 9.48 ± 22.3 pg/mg) and a correlation of the matched pairs was observed (r = 0.552, P < 0.01, n = 529). Evaluating each gender separately revealed that the correlation of male fingernail to male hair was large and significant (r = 0.782, P < 0.01, n = 195) while female hair to female fingernail was small yet sig-nificant (r = 0.249, P < 0.01, n = 334). The study results demonstrated that fingernail may be a suitable alternative to hair for ethyl glucuronide detection and may be the preferred sample type due to the lack of a gender bias. 展开更多
关键词 ALCOHOL Biomarkers Liquid Chromatography-Tandem mass SPECTROMETRY LC-MS/MS ethyl GLUCURONIDE Fingernail HAIR
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乙酸乙酯键联卟啉的合成与表征 被引量:1
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作者 范少华 崔玉民 《河南科技大学学报(自然科学版)》 CAS 2005年第2期98-101,i007,共5页
从5,10,15,20-四苯基卟啉合成5-(p-β-乙酸乙酯基氨基苯基)-10,15,20-三苯基卟啉5,10,15,20-四苯基卟啉(A)与发烟硝酸反应得到5-(对-硝基苯基)-10,15,20-三苯基卟啉(B),产率48.7%;B与二氯化锡进行还原反应得到5-(对-氨基苯基)-10,15,20... 从5,10,15,20-四苯基卟啉合成5-(p-β-乙酸乙酯基氨基苯基)-10,15,20-三苯基卟啉5,10,15,20-四苯基卟啉(A)与发烟硝酸反应得到5-(对-硝基苯基)-10,15,20-三苯基卟啉(B),产率48.7%;B与二氯化锡进行还原反应得到5-(对-氨基苯基)-10,15,20-三苯基卟啉(C),产率72.0%;C在无水碳酸钾和无水碘化钾催化下与氯乙酸乙酯进行亲核取代反应得到5-(p-β-乙酸乙酯基氨基苯基)-10,15,20-三苯基卟啉(D),产率8.5%。该方法的反应条件温和,合成路线短,纯化方法简单。 展开更多
关键词 线
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基于Web of Science的精喹禾灵研究热点与趋势的可视化分析
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作者 杨丽莉 刘春光 +2 位作者 付海燕 宋新宇 杨峰山 《中国农学通报》 2024年第18期140-149,共10页
本研究旨在客观分析精喹禾灵(Quizalofop-p-ethyl)领域的研究现状,并揭示其研究前沿,以期为相关学者提供科学的数据参考。通过科学引文索引扩展版SCIE检索“Quizalofop-p-ethyl”,查到2007-2023年间181篇相关文献,并从中获取了精喹禾灵... 本研究旨在客观分析精喹禾灵(Quizalofop-p-ethyl)领域的研究现状,并揭示其研究前沿,以期为相关学者提供科学的数据参考。通过科学引文索引扩展版SCIE检索“Quizalofop-p-ethyl”,查到2007-2023年间181篇相关文献,并从中获取了精喹禾灵发文量、发文研究机构和作者等信息。借助Python和VOSviewer工具,进行了精喹禾灵研究领域关键词共现图谱的可视化分析。主要研究结果有:(1)精喹禾灵领域世界发文量和被引频次整体呈上升趋势,中国为发文量最多的国家,前10位世界发文量的研究机构大部分来自中国;(2)发文量最多的作者为美国的Webster EP,来自中国的研究机构篇均被引频次均较高;(3)研究热点主要聚集在降解和除草剂等方面。综上所述,中国在精喹禾灵研究领域处于领先地位,国内学者具有较强的研究实力和国际影响力。然而,近年来中国的发文量有所下降,面对日益深入的研究需求,中国需要持续努力以保持其领先优势。 展开更多
关键词 Web of Science 沿
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