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2-Ethyl-9,10-anthraquinone assisted sol–gel synthesis of Pd/γ-Al2O3 nanorods with enhanced catalytic performance in 2-ethyl-9,10-anthraquinone hydrogenation 被引量:5
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作者 Weiquan Cai Junlin Zhuo +1 位作者 Jimin Fang Zhichao Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第8期1863-1869,共7页
A series of nanorod-like porous Pd/γ-Al2 O3 catalysts with controllable textural properties and enhanced catalytic performance in 2-ethyl-9,10-anthraquinone(eAQ) hydrogenation for H2 O2 preparation were successfully ... A series of nanorod-like porous Pd/γ-Al2 O3 catalysts with controllable textural properties and enhanced catalytic performance in 2-ethyl-9,10-anthraquinone(eAQ) hydrogenation for H2 O2 preparation were successfully prepared via a facile sol-gel method using aluminum isopropoxide as aluminum precursor and eAQ as structure directing agent,sequential calcination and impregnation process with Na2 PdCl4 solution.The physicochemical properties of the catalysts obtained with different addition amounts of eAQ.were comparatively characterized by XRD,TG-DSC,BET,TEM,CO-TPR,H2-TPR and H2-O2 titration.The results show that addition of eAQ can not only effectively control the textural properties(surface area,pore volume and average pore size) of the catalysts,but also lower their reduction temperature of active metal.Importantly,the catalyst obtained with an addition amount of 4 wt% eAQ shows the highest hydrogenation efficiency of 10.28 g·L^-1,which is 37.3% higher than 7.49 g·L^-1 of the catalyst obtained without eAQ. 展开更多
关键词 Catalyst HYDROGENATION Alumina 2-ethyl-9 10-anthraquinone Structure directing agent H2O2
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Investigation on removal pathways of Di 2-ethyl hexyl phthalate from synthetic municipal wastewater using a submerged membrane bioreactor 被引量:2
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作者 Mehdi Zolfaghari Patrick Drogui +4 位作者 Brahima Seyhi Satinder Kaur Brar Gerardo Buelna Rino Dubé Nouha Klai 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第11期37-50,共14页
Highly hydrophobic Di 2-ethyl hexyl phthalate(DEHP) is one of the most prevalent plasticizers in wastewaters. Since its half-life in biological treatment is around 25 days, it can be used as an efficiency indicator ... Highly hydrophobic Di 2-ethyl hexyl phthalate(DEHP) is one of the most prevalent plasticizers in wastewaters. Since its half-life in biological treatment is around 25 days, it can be used as an efficiency indicator of wastewater treatment plant for the removal of hydrophobic emerging contaminants. In this study, the performance of submerged membrane bioreactor was monitored to understand the effect of DEHP on the growth of aerobic microorganisms. The data showed that the chemical oxygen demand(COD)and ammonia concentration were detected below 10 and 1.0 mg/L, respectively for operating conditions of hydraulic retention time(HRT) = 4 and 6 hr, sludge retention time(SRT) = 140 day and sludge concentration between 11.5 and 15.8 g volatile solid(VS)/L. The removal efficiency of DEHP under these conditions was higher and ranged between 91% and 98%. Results also showed that the removal efficiency of DEHP in biological treatment depended on the concentration of sludge, as adsorption is the main mechanism of its removal. For the submerged membrane bioreactor, the pore size is the pivotal factor for DEHP removal, since it determines the amount of soluble microbial products coming out of the process. Highly assimilated microorganisms increase the biodegradation rate, as 74% of inlet DEHP was biodegraded; however, the concentration of DEHP inside sludge was beyond the discharge limit. Understanding the fate of DEHP in membrane bioreactor,which is one of the most promising and futuristic treatment process could provide replacement for conventional processes to satisfy the future stricter regulations on emerging contaminants. 展开更多
关键词 Di 2-ethyl hexyl phthalate Submerged membrane bioreactor Removal efficiency Soluble microbial products Toxicity
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Synthesis and Crystal Structure of Tri(4-(3-hydroxy2-ethyl-4-pyridinone-1-yl)-aniline Condensation Salicylaldehydato) Monohydratotricopper(II)Dimethylformamide Monohydrate Solvate 被引量:2
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作者 LUZai-Sheng NIUDe-Zhong +1 位作者 TUShu-Jiang CHENJiu-Tong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第6期681-686,共6页
The title complex [Cu3L3(H2O)]DMFH2O (H2L = 4-(3-hydroxy-2-ethyl-4- pyridinone-1-yl)-aniline condensation salicylaldehyde) was obtained. The single-crystal X-ray study shows that it is a trinuclear compound [Cu3(C20H1... The title complex [Cu3L3(H2O)]DMFH2O (H2L = 4-(3-hydroxy-2-ethyl-4- pyridinone-1-yl)-aniline condensation salicylaldehyde) was obtained. The single-crystal X-ray study shows that it is a trinuclear compound [Cu3(C20H15N2O3)3(H2O)]DMFH2O. The coordi- nation sphere about each copper ion in the complex consists of two oxygen atoms from hydroxylpyridinone moiety of one ligand and one oxygen and one nitrogen atoms from salicyladehyde Schiff-base moiety of another ligand arranged in a slightly distorted square planar geometry. Among the three copper ions, one (Cu(2)) is coordinated by the other oxygen atom of water molecule on the fifth coordinate position to form a distorted square pyramid geometry. The crystal is of monoclinic, space group P21/c with a = 12.9202(5), b = 27.197(1), c = 17.0116(7) ? b = 100.588(1), V = 5875.9(4) 3, Z = 4, C63H57N7O12Cu3, Mr = 1294.78, Dc = 1.464 g/cm3, m = 1.146 mm-1, F(000) = 2668, R = 0.0784 and wR = 0.1546 for 6926 observed reflections with I > 2s(I). The differences of coordinate bond lengths are observed between anhydrous and hydrous units: in the former unit, the average bond lengths are 1.978 ?for CuN (azomethine), 1.883 ?for CuO (phenolic) in Schiff-base moiety, 1.959 ?for CuO (keto), and 1.919 ?for CuO (hydroxy) in hydroxypyridinone moiety; while those in the latter are longer with the following corresponding values: 1.985(5), 1.908(5), 1.993(5) and 1.919(4) ? respectively. The Cu(2)O (water) bond length is 2.375(6) ? 展开更多
关键词 copper(II) complex 4-(3-hydroxy-2-ethyl-4-pyridinone-1-yl)-aniline salicylaldehyde Schiff-base crystal structure
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Delivery of docetaxel using pH-sensitive liposomes based on D-α-tocopheryl poly(2-ethyl-2-oxazoline) succinate:Comparison with PEGylated liposomes 被引量:1
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作者 Shu Han Ruiyang Sun +4 位作者 Hong Su Jing Lv Huan Xu Di Zhang Yuanshan Fu 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2019年第4期391-404,共14页
This study aimed to investigate the ability of the novel materials D-α-tocopheryl poly(2-ethyl-2-oxazoline) succinate(TPOS) to construct pH-sensitive liposomes. TPOS was initially synthesized and characterized by TLC... This study aimed to investigate the ability of the novel materials D-α-tocopheryl poly(2-ethyl-2-oxazoline) succinate(TPOS) to construct pH-sensitive liposomes. TPOS was initially synthesized and characterized by TLC, FTIR, and ~1H-NMR. The buffering capacity of polyethylene glycol-distearoyl phosphatidylethanolamine(PEG-DSPE) and TPOS was determined by acid-base titration, and TPOS displayed a slower downtrend and gentler slope of titration curve than PEG-DSPE within pH 7.4–5.0. Studies on the in vitro drug release demonstrated that TPOS modified docetaxel(DOC) liposomes(TPOS-DOC-L) had a slower drugrelease rate at pH 7.4 similar to PEGylated-DOC liposomes(PEG-DOC-L), whereas the release rate reached approximately 86.92% ± 1.69% at pH 6.4. In vitro cellular uptake assays by microplate reader, and flow cytometry revealed that TPOS modified coumarin 6 liposomes(TPOS-C6-L) had stronger cellular uptake at pH 6.4 than that at pH 7.4( P < 0.01). Conversely, for PEGylated C6 liposomes(PEG-C6-L) and conventional C6 liposomes(C6-L), very similar cellular uptakes were exhibited at different pH values. Confocal laser scanning microscopy images showed that PEG-C6-L and C6-L were mainly located in lysosomes. By contrast, TPOS-C6-L showed broader cytoplasmic release and distribution at 4 h. MTT assay showed that the cytotoxicity of TPOS-DOC-L was similar to that of PEG-DOC-L and conventional DOC liposomes(DOC-L) at the same DOC concentration and at pH 7.4, but was much lower than those at pH 6.4 after 48 h of incubation. The apoptosis of PEG-DOC-L and DOC-L had no remarkable improvement with decreased pH from 7.4 to 6.4. Meanwhile, TPOS-DOC-Lsignificantly induced the apoptosis of HeLa cells with decreased pH. Therefore, TPOS can be a biomaterial for the construction of a pH-sensitive drug delivery system. 展开更多
关键词 d-α-tocopheryl poly(2-ethyl-2-oxazoline) SUCCINATE Liposomes PH-SENSITIVE PEGYLATION
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Extraction of Gold by Di(2-ethylhexyl)Sulfoxide and N-Octyl Sulfoxide
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作者 Lu Zhong’e, Que Haoquan, Liu Guoxing, Wang Hanzhang and Zhu Qinhua (Department of Chemistry, Suzhou University, Suzhou) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1989年第3期231-236,共6页
A long chain aliphatic sulfoxide can be used as an extractant.It can extract almost all metallic ions which can be extracted by tributylphosphate (TBP).The extraction of gold was studied by Chekushin,V. S. and Mojski,... A long chain aliphatic sulfoxide can be used as an extractant.It can extract almost all metallic ions which can be extracted by tributylphosphate (TBP).The extraction of gold was studied by Chekushin,V. S. and Mojski,M.using petroleum sulfoxide and n-dioctyl sulfoxide(DOSO) as an extractant respectively. 展开更多
关键词 EXTRACTION Di(2-ethyl hexyl)sulfoxide N-octyl sulfoxide GOLD
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Preparation and Catalytic Activity of PW_(12)/PAn Material in Synthesis of 2-Methyl-2-Ethyl Acetoacetate-1,3-Dioxolane
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作者 YANG Shui-jin YU Xie-qing +1 位作者 LU Bao-lan SUN Ju-tang 《合成化学》 CAS CSCD 2004年第z1期47-47,共1页
关键词 Methyl-2-ethyl acetoacetate-1 3-dioxolane PW12/PAn ketalation catalysis.
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MECHANISM-TRANSFORMATION SYNTHESIS AND CHARACTERIZATION OF POLY(STYRENE-b-2-ETHYL-2-OXAZOLINE) DIBLOCK COPOLYMER
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作者 Sheng-qing Xu Han-ying Zhao +1 位作者 Tao Tang Bao-tong Huang Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1999年第2期145-150,共6页
By mechanism-transformation (anionic --> cationic) poly(styrene-6-2-ethyl-2-oxazoline) diblock copolymer, PS-b-PEOx, was synthesized in two steps. The first step is the polymerization of styrene block capped with e... By mechanism-transformation (anionic --> cationic) poly(styrene-6-2-ethyl-2-oxazoline) diblock copolymer, PS-b-PEOx, was synthesized in two steps. The first step is the polymerization of styrene block capped with ethylene oxide and its tosylation; the second step is the cationic ring-opening polymerization of 2-ethyl-2-oxazoline. The products were thoroughly characterized by various methods, such as H-1-NMR, IR, DMA, TEM and SAXS. The results show that the copolymer obtained possesses high molecular weight and narrow molecular weight distribution. 展开更多
关键词 diblock copolymer mechanism-transformation polymerization 2-ethyl-2-oxazoline STYRENE characterization
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Synthesis of (S)-N-(2-Ethyl-6-methylphenyl) alanine by Enzyme-catalyzed Resolution and Chemical Racemization
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作者 ZHENG Liang-yu ZHANG Suo-qin +1 位作者 LU Xiao-li CAO Shu-gui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第6期836-840,共5页
A practical synthesis of (S)-N-(2-ethyl-6-methylphenyl)alanine, a key intermediate for (S)-metolachlor, was completed by means of lipase-catalyzed hydrolytic kinetic resolution and chemical racemization of the r... A practical synthesis of (S)-N-(2-ethyl-6-methylphenyl)alanine, a key intermediate for (S)-metolachlor, was completed by means of lipase-catalyzed hydrolytic kinetic resolution and chemical racemization of the remaining ester. The effects of operating temperature and enzyme concentration on the activity and enantioselectivity of enzyme were initially studied, and it was found that the enantioselectivity of CAL-B towards the resolution was not high enough to obtain enantiomerically pure compound(E=12.1). When diethyl ether(15%, volume fraction) was added in the reaction medium, the lipase gave an excellent enantioselectivity(E=117.8), which is about 9.7-fold that in pure buffered aqueous solution. For overcoming the limitation of a maximum theoretical yield of 50%, the acid product was separated from the remaining ester by a simple extraction procedure and the remaining ester was racemized with aldehyde and acetic acid under microwave irradiation or conventional heating condition, The results show the microwave irradiation was more effective than the conventional heating method and gave the desired (R,S)-N-(2- ethyl-6-methylphenyl)alanine methyl ester a high yield(92%) with R/S=50/50 in 1 h. 展开更多
关键词 Candida antarctica lipase B RESOLUTION (S)-N-(2-ethyl-6-methylphenyl)alanine RACEMIZATION
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Synthesis and Crystal Structure of cis-Bis(3-hydroxy2-ethyl-4-pyranonato)dioxomolybdenum(Ⅵ)
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作者 LU Zai-Sheng② NIU De-Zhong LI Xiu-Ling (Department of University, Xuzhou Normal University, Xuzhou 221009, China) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第5期573-576,共4页
The complex MoO2(C7H7O3)2 has been prepared by the reaction of 3-hydroxy- 2-ethyl-4-pyranone with (NH4)6Mo7O244H2O. The single-crystal X-ray study shows that the coordination sphere about the molybdenum atom in the co... The complex MoO2(C7H7O3)2 has been prepared by the reaction of 3-hydroxy- 2-ethyl-4-pyranone with (NH4)6Mo7O244H2O. The single-crystal X-ray study shows that the coordination sphere about the molybdenum atom in the complex consists of six oxygen atoms arranged in a distorted octahedral geometry with the dioxo ligands in cis positions. The crystal is of monoclinic, space group P21/c with a = 8.3968(2), b = 12.7534(4), c = 14.5443(4) ? b = 96.277(1), V = 1548.18(7) ?, Z = 4, C14H14O8Mo, Mr = 406.19, Dc = 1.743g/cm3, m = 0.886mm-1, F(000) = 816, R = 0.0444 and wR = 0.1091 for 2336 observed reflections with I>2s(I). The average Mo=O bond length is 1.695(4) ? The two ketonic oxygen atoms of the pyranone moieties are trans to the oxo ligands and the hydroxy oxygen atoms are trans to each other. The average MoO bond lengths are 2.248(4) ?for the ketone oxygens and 2.005(3) ?for the hydroxy oxygens. The average ligand bite angle of OMoO is 75.2(2) and the bond angle between two Mo=O is 105.1(2). The dihedral angle is 79.16(2)?between two chelate ring planes. 展开更多
关键词 crystal structure molybdenum(VI) complex 3-hydroxy-2-ethyl-4-pyranone
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Synthesis and Crystal Structure of Tris(N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinonato)iron(III)
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作者 路再生 牛德仲 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第6期466-469,共4页
The complex [Fe(C14H14NO2)3]2H2O has been prepared by reaction of N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinone with FeCl36H2O. A single-crystal X-ray study shows that the iron atoms lie in a trigonally distorted oc... The complex [Fe(C14H14NO2)3]2H2O has been prepared by reaction of N-p-methylphenyl-3-hydroxy-2-ethyl-4-pyridinone with FeCl36H2O. A single-crystal X-ray study shows that the iron atoms lie in a trigonally distorted octahedral environment coordinated to the hydroxy and ketone oxygen atoms of three ligands in the mer configuration Mr=773.57(C42H46N3O8Fe). The crystal is hexagonal with space group P31c; a=15.943(2), c=17.612(4)? V=3877.0(12)?, Z=4, Dc=1.325g/cm3, m=0.445mm-1, F(000)=1634, R=0.0446, wR= 0.1154 for 3085 reflections with I >2s(I). The bond lengths from iron to oxygens are 1.980(1)?for the ketone oxygens and 2.071(1)?for the hydroxy oxygens. The molecule exhibits the expected propeller shape, and the angle of the trigonal twist is 48.37. The dihedral angles are 0.5(2)?between chelate ring plane and pyridine ring plane and 71.31(7)?between pyridine ring plane and benzene ring plane. The solvent H2O(O(3) and O(4)) molecules are linked with O(2) and O(1) by hydrogen bonds with bond lengths 2.900(1) and 2.999(1)? respectively. 展开更多
关键词 crystal structure iron(III) complex N-p-methylphenyl-3- hydroxy-2-ethyl-4- pyridinone
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Cell Death Effects of the Phthalate 2-Ethyl-1-Hexanol on Human Linfoblast Cells
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作者 Karoline Rios Christian Vélez Beatriz Zayas 《Open Journal of Apoptosis》 2019年第1期1-15,共15页
Phthalates have been used in a wide variety of consumer goods. Their versatility as plasticizers has translated into worldwide use in a vast array of consumer products. These compounds can leach into matrices, such as... Phthalates have been used in a wide variety of consumer goods. Their versatility as plasticizers has translated into worldwide use in a vast array of consumer products. These compounds can leach into matrices, such as food and liquids that can be routed for human exposure. One of the most used phthalates is Diethylhexyl phthalate (DEHP). Diethylhexyl phthalate and its metabolite 2-ethyl-1-hexanol (2-EH) have demonstrated biological effects which merit further evaluation. In this work, we expand on our previous work with DEHP and screen the 2-EH metabolite for different cell death endpoints such as growth inhibition, apoptosis, autophagy, caspase activation, DNA fragmentation, and cell cycle arrest using fluorophores and the NC3000 instrument. Significant results (p 0.05) revealed higher toxicity for the 2-EH metabolite when compared to DEHP. Also, 2-EH presented apoptosis induction with characteristic hallmarks, such as loss of mitochondrial membrane potential, caspase activation, DNA fragmentation and cell cycle arrest at the S phase. In addition, the presence of autophagosome was detected through L3CB protein staining. We conclude that 2-EH presents differences in cell death endpoints that interestingly differ from the DEHP parent compound. Further studies are needed to establish the molecular pathways responsible for the observed effects. 展开更多
关键词 PHTHALATES 2-ethyl-1-Hexanol Diethylhexyl PHTHALATE Autophagy Apoptosis LYMPHOBLAST Caspase
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2-氯乙基乙基硫醚暴露对淡水微藻光合代谢的影响及毒理效应
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作者 王莹 郑升 +3 位作者 赖金龙 付倩 张宇 罗学刚 《生态毒理学报》 北大核心 2026年第1期503-513,共11页
硫芥类化合物模拟剂2-氯乙基乙基硫醚(2-CEES)因潜在环境泄漏风险可能威胁水生生态系统,但其对淡水微藻的水生态毒理效应鲜有报道。本研究以9种淡水微藻(含蓝藻、绿藻、红藻)为对象,经2-CEES暴露后,分析藻液理化参数、叶绿素荧光动力学... 硫芥类化合物模拟剂2-氯乙基乙基硫醚(2-CEES)因潜在环境泄漏风险可能威胁水生生态系统,但其对淡水微藻的水生态毒理效应鲜有报道。本研究以9种淡水微藻(含蓝藻、绿藻、红藻)为对象,经2-CEES暴露后,分析藻液理化参数、叶绿素荧光动力学及微藻代谢谱的变化,解析2-CEES暴露对微藻光合电子传递链与碳代谢途径的毒理机制。结果显示,2-CEES导致微藻pH显著降低(2.6%~13.0%)、电导率升高1.93%~10.29%;其中,紫球藻和片状微囊藻生长受抑制最显著,表现出明显的种间差异。藻类叶绿素荧光参数显示,经2-CEES暴露,7种微藻光系统Ⅱ(PSⅡ)最大光化学效率(F_(v)/F_(m))显著降低,单位反应中心光能捕获(ABS/RC)与热耗散(DI_(o)/RC)增强,但电子传递活性(ET_(o)/RC)受抑,表明微藻光反应能量转化效率下降。代谢组学分析共鉴定2404个代谢物,KEGG富集通路显示,14种碳水化合物显著富集于糖酵解、磷酸戊糖途径(PPP)及卡尔文循环,其中10种代谢物在处理组间呈现显著性差异(P<0.05)。结果表明,2-CEES通过破坏PSⅡ反应中心电子传递、诱导代谢能量再分配,抑制微藻光合碳同化效率,其毒性效应具有显著种属特异性,该结果可为硫芥类污染物生态风险评估及生物标志物开发提供理论依据。 展开更多
关键词 2-氯乙基乙基硫醚 淡水微藻 光合代谢 叶绿素荧光动力学 生态风险评估
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乙酰丙酸乙酯加氢脱水一体化合成2-甲基四氢呋喃
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作者 王洪星 于富红 +3 位作者 张帅 李宁宁 田野 李新刚 《化工学报》 北大核心 2026年第1期356-365,共10页
乙酰丙酸乙酯(EL)加氢制1,4-戊二醇(1,4-PDO)和2-甲基四氢呋喃(2-MTHF)普遍采用极低的反应物浓度,以间歇釜式反应为主,不利于连续的规模化生产。为了提高生产效率,在固定床反应器上采用Cu基催化剂进行EL无溶剂加氢制1,4-PDO,并在HZSM-5... 乙酰丙酸乙酯(EL)加氢制1,4-戊二醇(1,4-PDO)和2-甲基四氢呋喃(2-MTHF)普遍采用极低的反应物浓度,以间歇釜式反应为主,不利于连续的规模化生产。为了提高生产效率,在固定床反应器上采用Cu基催化剂进行EL无溶剂加氢制1,4-PDO,并在HZSM-5分子筛作用下将后者原位脱水转化为2-MTHF。通过双固体催化剂分段组装可以在更低的反应温度下获得更优越的反应性能,较文献釜式反应器的温度低40℃及以上,EL转化率和2-MTHF选择性分别可达99.9%和97.8%。同时考察了绿铜锌矿、锌孔雀石和类水滑石等CuZn(Al)催化剂不同前体对EL加氢制1,4-PDO的影响,采用N2物理吸附、XRD、FTIR、H_(2)-TPR、NH_(3)-TPD、CO_(2)-TPD和原位XPS等表征技术对CuZn(Al)催化剂进行了系统的分析。结果表明,绿铜锌矿衍生的45CZ催化剂具有更高比例的Cu+位点,能更好地吸附和活化中间产物γ-戊内酯(GVL),同时具有适量的酸碱性位点,Cu+位点和酸碱性位点协同作用使得该催化剂表现出最佳的1,4-PDO选择性。本研究可为2-MTHF的规模化生产提供参考。 展开更多
关键词 乙酰丙酸乙酯 1 4-戊二醇 2-甲基四氢呋喃 催化剂 加氢
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Synthesis and characterization of diblock copolymer of butadiene and 2-ethyl-2-oxazoline
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作者 徐胜清 黄葆同 《Science China Chemistry》 SCIE EI CAS 1998年第2期194-201,共8页
By mechanism transformation (anionic cationic) polymerization, diblock copolymer of butadiene and 2 ethyl 2 oxazoline (PBd b PEOx) was synthesized in two steps. The first step is the polymerization of butadiene bloc... By mechanism transformation (anionic cationic) polymerization, diblock copolymer of butadiene and 2 ethyl 2 oxazoline (PBd b PEOx) was synthesized in two steps. The first step is the polymerization of butadiene block capped with ethylene oxide and its tosylation; the second step is the cationic ring opening polymerization of 2 ethyl 2 oxazoline. The products were characterized by various methods, such as IR, 1HNMR, DMA, TEM and SAXS. The results show that the obtained copolymers possess high molecular weight and narrow molecular weight distribution, and that the content of 1,4 structure was controllable. 展开更多
关键词 2-ethyl 2 OXAZOLINE BUTADIENE block COPOLYMER mechanism transformation POLYMERIZATION charac terization.
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Microtropins J-P: 6’-O-(2”<i>S</i>,3”<i>R</i>)-2”-Ethyl-2”,3”-Dihydroxybutyrates of Phenolic Alcohol <i>&#223</i>-D-Glucopyranosides from the Branches of <i>Microtropis japonica</i>
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作者 Yuka Uemura Sachiko Sugimoto +2 位作者 Katsuyoshi Matsunami Hideaki Otsuka Yoshio Takeda 《American Journal of Plant Sciences》 2013年第10期1954-1959,共6页
From the branches of Microtropis japonica (Celastraceae), seven phenolic alcohol glucosides, named microtropins J-P (1-7), were isolated. The 6-position of glucose was esterified with 2-ethyl-2,3-dihydroxybutyric acid... From the branches of Microtropis japonica (Celastraceae), seven phenolic alcohol glucosides, named microtropins J-P (1-7), were isolated. The 6-position of glucose was esterified with 2-ethyl-2,3-dihydroxybutyric acid. Microtropin K (2) was hydrolyzed under a mild basic condition to give methyl (2S,3R)-2-ethyl-2,3-dihydroxybutyrate, whose absolute structure was determined by the comparison of NMR data and the optical rotation value with that reported. 展开更多
关键词 Microtropis JAPONICA CELASTRACEAE Microtropin (2S 3R)-2-ethyl-2 3-Dihydroxybutyrate
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芽孢杆菌C1对2-氯乙基乙基硫醚的脱氯性能及代谢响应机制
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作者 晏磊 赖金龙 +2 位作者 付倩 张宇 罗学刚 《生态毒理学报》 北大核心 2025年第4期303-315,共13页
2-氯乙基乙基硫醚(2-chloroethyl ethyl sulfide,2-CEES)作为一种氯代烷烃,被用作研究有机氯类污染降解的模拟物质。本研究以2-CEES污染土壤中分离出的一株芽孢杆菌C1为对象,评估了其对2-CEES的脱氯能力,通过单因素实验结合响应曲面法... 2-氯乙基乙基硫醚(2-chloroethyl ethyl sulfide,2-CEES)作为一种氯代烷烃,被用作研究有机氯类污染降解的模拟物质。本研究以2-CEES污染土壤中分离出的一株芽孢杆菌C1为对象,评估了其对2-CEES的脱氯能力,通过单因素实验结合响应曲面法优化其降解效果,利用非靶向代谢组学探究细菌对2-CEES污染的生物降解特性,利用气相色谱-质谱(GC-MS)检测有机相,预测了2-CEES的生物降解路径。结果显示,芽孢杆菌C1在4-羟乙基哌嗪乙磺酸-氢氧化钠(HEPES-NaOH)缓冲液浓度为82.29 mmol·L^(-1),丙三醇的体积分数20.54%,培养到第50.30小时对2-CEES(1.0 mg·mL-1)的脱氯率达82.20%。通过KEGG富集分析发现,2-CEES胁迫显著影响芽孢杆菌C1的代谢网络,特别是硫代谢、精氨酸生物合成和能量代谢途径。高浓度2-CEES胁迫可抑制细菌精氨酸生物合成、鸟氨酸循环代谢水平,但激活了苯丙氨酸代谢通路、苯甲酸酯降解水平,进而提高细胞对2-CEES污染的代谢能力。而低浓度胁迫下促进自身的代谢水平,如精氨酸生物合成和氧化磷酸化途径。通过对检测到的有机物进行生物降解路径预测,发现除了2-CEES的脱氯反应和取代基的直接水解反应外,还发生了活泼中间体自由基的二次聚合过程。 展开更多
关键词 2-氯乙基乙基硫醚 芽孢杆菌 生物刺激 代谢组学
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基于2-硝基查尔酮与异氰基乙酸乙酯的串联环化反应合成α-咔啉酮类化合物
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作者 盛馨瑶 李鑫鑫 +3 位作者 邢潇 潘玲 刘群 李亦菲 《有机化学》 北大核心 2025年第6期2163-2170,共8页
α-咔啉酮类化合物广泛存在于多种天然产物及药物活性分子中,其合成方法具有重要的研究意义和应用价值.发现了一种新颖、实用的基于2-硝基查尔酮与异氰基乙酸乙酯的串联环化反应,可用于高效合成α-咔啉酮类化合物.该合成过程通过一步反... α-咔啉酮类化合物广泛存在于多种天然产物及药物活性分子中,其合成方法具有重要的研究意义和应用价值.发现了一种新颖、实用的基于2-硝基查尔酮与异氰基乙酸乙酯的串联环化反应,可用于高效合成α-咔啉酮类化合物.该合成过程通过一步反应实现了两个氮杂环系的构建和多个化学键的形成与转化,且涉及的还原环化过程无需外加还原剂.该反应操作简便,原料廉价易得,反应条件绿色温和,是一种有效且实用的咔啉酮类化合物合成方法. 展开更多
关键词 α-咔啉酮 2-硝基查尔酮 异氰基乙酸乙酯 串联环化反应
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SiO_(2)助剂对铜基催化剂上辛烯醛加氢制辛醇反应副产物选择性的影响
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作者 刘洁 孙远龙 +3 位作者 李婷婷 于杨 李忠于 郭学锋 《低碳化学与化工》 北大核心 2025年第7期38-44,57,共8页
辛烯醛气相法加氢是工业领域生产2-乙基己醇(下称“辛醇”)的主要方法,该过程的副产物种类和选择性对辛醇品质和产量有直接影响。为获得具有较高催化活性的催化剂并控制副产物选择性,制备了铜(Cu)基催化剂,并采用SiO_(2)作为助剂对催化... 辛烯醛气相法加氢是工业领域生产2-乙基己醇(下称“辛醇”)的主要方法,该过程的副产物种类和选择性对辛醇品质和产量有直接影响。为获得具有较高催化活性的催化剂并控制副产物选择性,制备了铜(Cu)基催化剂,并采用SiO_(2)作为助剂对催化剂进行了改性。评价了所得催化剂(N-1、N-2和N-3)的辛烯醛气相加氢催化性能,并结合XRD、N_(2)吸/脱附、XPS、TEM、NH_(3)-TPD和Py-IR等多种表征方式对催化剂进行了表征。结果表明,催化剂的催化活性与催化剂中CuO分散度和Lewis酸量相关。其中在入口温度为150℃、反应压力为0.4 MPa和辛烯醛进料液空速为0.3 h^(-1)的条件下,SiO_(2)含量(质量分数,下同)为0的N-1的辛烯醛转化率为99.76%,辛醇选择性为99.50%,加氢产物中部分加氢副产物2-乙基己醛和2-乙基己烯醇含量分别为0.22%和0.04%,重组分含量为1.06%;SiO_(2)能够修饰催化剂表面性质,定向降低重组分产物选择性,SiO_(2)含量为2%的N-2的辛烯醛转化率为99.49%,辛醇选择性为99.40%,2-乙基己醛、2-乙基己烯醇和重组分含量分别为0.28%、0.06%和0.72%。在总计10个月的工业应用验证中,N-2表现出较好的催化性能,其2-乙基己醛、辛醇和重组分含量的均值分别为小于0.01%、97.88%和0.42%。 展开更多
关键词 辛烯醛加氢 铜基催化剂 2-乙基己醇 SiO_(2) 副产物选择性
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Synthesis and Antitumor Activity of 3-[2-(4-Hydroxy-Phenyl)-Ethyl]-Benzo[d] Isoxazole-4,6-Diol
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作者 Li Wang 《International Journal of Organic Chemistry》 CAS 2023年第1期1-6,共6页
A new phloretin derivative 1 3-[2-(4-hydroxy-phenyl)-ethyl]-benzo[d] isoxazole-4,6-diol (yield 63%) was synthesized from phloretin by carbonyl nucleophilic addition condensation reaction. Its structure was characteriz... A new phloretin derivative 1 3-[2-(4-hydroxy-phenyl)-ethyl]-benzo[d] isoxazole-4,6-diol (yield 63%) was synthesized from phloretin by carbonyl nucleophilic addition condensation reaction. Its structure was characterized by 1H NMR, 13C NMR and HR-MS. The phloretin, compound 1, resveratrol and acetylated resveratrol were determined by comparing them with paclitaxel. Anti-tumor activity of alcohol on SPC-A1, EC109, A549, MCF-7 and MDA-MB-231 cell lines. Compound 1 showed better antitumor activity than docetaxel against A549 tumor cells. 展开更多
关键词 3-[2-(4-Hydroxy-Phenyl)-ethyl]-Benzo[d] Isoxazole-4 6-Diol SYNTHESIS Antitumor Activity
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不同香型白酒中2-羟基-3-甲基丁酸乙酯对映体的分布及感官特性
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作者 余成霞 朱建猛 +4 位作者 王超 顾莎莎 韦朝阳 邱树毅 戴怡凤 《中国酿造》 北大核心 2025年第7期58-66,共9页
该研究利用液液萃取(LLE)结合气相色谱(GC)和手性气相色谱-质谱(Chiral-GC-MS)分析白酒中2-羟基-3-甲基丁酸乙酯(E2H3MB),优化其气相色谱分析条件,对12种香型白酒中E2H3MB对映体分布情况进行探究,并利用三点选配(3-AFC)阈值测定方法,评... 该研究利用液液萃取(LLE)结合气相色谱(GC)和手性气相色谱-质谱(Chiral-GC-MS)分析白酒中2-羟基-3-甲基丁酸乙酯(E2H3MB),优化其气相色谱分析条件,对12种香型白酒中E2H3MB对映体分布情况进行探究,并利用三点选配(3-AFC)阈值测定方法,评估E2H3MB对映体在纯水和体积分数46%乙醇溶液中的嗅觉阈值及感官特征。结果表明,CYCLOSIL-B色谱柱(30 m×0.25 mm×0.25μm)对E2H3MB分离效果良好,升温速率1.5℃/min,载气流速为1.0 mL/min时,E2H3MB对映体分离情况最佳,分离度(R)=5.0>1.5。除了米香型、清香型以及豉香型白酒,其他香型白酒中均只检测到(R)-构型E2H3MB((R)-E2H3MB),且同一香型白酒中(R)-E2H3MB含量存在显著差异(P<0.05)。感官特征结果表明,在纯水和体积分数46%乙醇溶液中,(R)-E2H3MB嗅觉阈值分别是(S)-构型E2H3MB((S)-E2H3MB)的2.1倍左右((R)-构型38μg/L;(S)-构型18μg/L)和1.9倍左右((R)-构型322 mg/L;(S)-构型173 mg/L),两种构型均表现出令人愉悦的甜香以及果香。该研究结果有助于白酒风味轮的细化,为研究白酒中手性风味物质对映体的分布提供参考依据,丰富人们对白酒中手性风味物质的认识。 展开更多
关键词 白酒 2-羟基-3-甲基丁酸乙酯 手性风味物质 对映体 感官特征
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