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Steam reforming of acetic acid over Ni/biochar of low metal-loading:Involvement of biochar in tailoring reaction intermediates renders superior catalytic performance
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作者 Yunyu Guo Yiran Wang +5 位作者 Shu Zhang Yi Wang Song Hu Jun Xiang Walid Nabgan Xun Hu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期241-252,共12页
Biochar is a reactive carrier as it may be partially gasified with steam in steam reforming,which could influence the formation of reaction intermediates and modify catalytic behaviors.Herein,the Ni/biochar as well as... Biochar is a reactive carrier as it may be partially gasified with steam in steam reforming,which could influence the formation of reaction intermediates and modify catalytic behaviors.Herein,the Ni/biochar as well as two comparative catalysts,Ni/Al_(2)O_(3) and Ni/SiO_(2),with low nickel loading(2%(mass))was conducted to probe involvement of the varied carriers in the steam reforming.The results indicated that the Ni/biochar performed excellent catalytic activity than Ni/SiO_(2) and Ni/Al_(2)O_(3),as the biochar carrier facilitated quick conversion of the -OH from dissociation of steam to gasify the oxygen-rich carbonaceous intermediates like C=O and C-O-C,resulting in low coverage while high exposure of nickel species for maintaining the superior catalytic performance.In converse,strong adsorption of aliphatic intermediates over Ni/Al_(2)O_(3) and Ni/SiO_(2) induced serious coking with polymeric coke as the main type(21.5%and 32.1%,respectively),which was significantly higher than that over Ni/biochar(3.9%).The coke over Ni/biochar was mainly aromatic or catalytic type with nanotube morphology and high crystallinity.The high resistivity of Ni/biochar towards coking was due to the balance between formation of coke and gasification of coke and partially biochar with steam,which created developed mesopores in spent Ni/biochar while the coke blocked pores in Ni/Al_(2)O_(3) and Ni/SiO_(2) catalysts. 展开更多
关键词 Steam reforming Acetic acid Ni/biochar catalyst Property of coke Reaction intermediates
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Steam reforming of acetic acid over Ni-Ba/Al2O3 catalysts:Impacts of barium addition on coking behaviors and formation of reaction intermediates 被引量:5
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作者 Zhanming Zhang Yiran Wang +7 位作者 Kai Sun Yuewen Shao Lijun Zhang Shu Zhang Xiao Zhang Qing Liu Zhenhua Chen Xun Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第4期208-219,共12页
The influence of barium addition to a Ni/Al2O3 catalyst on the reaction intermediates formed,the activity,resistance of the catalyst to coking,and properties of the coke formed after acetic acid steam reforming were i... The influence of barium addition to a Ni/Al2O3 catalyst on the reaction intermediates formed,the activity,resistance of the catalyst to coking,and properties of the coke formed after acetic acid steam reforming were investigated in this study.The results showed the drastic effects of barium addition on the physicochemical properties and performances of the catalyst.The solid-phase reaction between alumina and BaO formed BaAl2O4,which re-constructed the alumina structure,resulting in a decrease in the specific surface area and an increase in the resistance of metallic Ni to sintering.The addition of barium was also beneficial for enhancing the catalytic activity,resulting from the changed catalytic reaction network.The in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) study of the acetic acid steam reforming indicated that barium could effectively suppress the accumulation of the reaction intermediates of carbonyl,formate,and C=C functional groups on the catalyst surface,attributed to its relatively high ability to cause the gasification of these species.In addition,coking was considerably more significant over the Ba-Ni/Al2O3 catalyst.Moreover,the Ba-Ni/Al2O3 catalyst was more stable than the Ni/Al2O3catalyst,owing to the distinct forms of coke formed (carbon nanotube form over the Ba-Ni/Al2O3 catalyst,and the amorphous form over the Ni/Al2O3 catalyst). 展开更多
关键词 BARIUM ADDITION Nickel-based CATALYSTS Steam reforming of acetic acid Reaction intermediateS COKING BEHAVIORS
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Geological characteristics and metallogenic significance of the Devonian intermediate-basic volcanic rocks in the Dachang deposit, Guangxi Zhuang Autonomous Region 被引量:9
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作者 YAN Yongfeng LIU Chenming +1 位作者 QIN Dexian JIANG Kai 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2013年第1期110-118,共9页
Recently discovered intermediate-basic volcanic rocks in the Devonian strata at Dachang, Guangxi Zhuang Autonomous Region are dominated by basalts and andesites. Most of them belong to the calc-alkali and alkali serie... Recently discovered intermediate-basic volcanic rocks in the Devonian strata at Dachang, Guangxi Zhuang Autonomous Region are dominated by basalts and andesites. Most of them belong to the calc-alkali and alkali series. Petrology and geochemistry data indicate that the volcanic rocks may be formed in a continental rift environment. The volcanic rocks are in conformable contact with the overlying and underlying wall rocks, with such typical sedimentary structures as laminated and striped ones, and the host rocks of the volcanic rocks contain lots of marine fossils such as tentaculite. Many pieces of evidence indicate that the eruption environment of the volcanic rocks is a sea-facies one. The volcanic rocks are of the LREE-enrichment type, with high ratios of light rare-earth elements to heavy rare-earth elements. In addition, they display moderately negative δEu anomalies and moderately negative δCe anomalies with a higher degree of LREE and HREE fractionation. Through the Q-cluster analysis of the REE samples, it is indicated that the ores have a closer relation with the layered volcanic rocks, and also possess a certain inheritance-consistency relationship with the layered volcanic rocks. The source of ore-forming materials may be related with volcanism. It is proposed that the ore deposit in the study area should be genetically explained as the result of marine volcano-sedimentary exhalation of hot water and late superposition-reworking. 展开更多
关键词 广西壮族自治区 基性火山岩 成矿意义 地质特征 矿床 泥盆系 轻稀土元素 重稀土元素
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Formation mechanism of high-quality reservoirs in intermediate volcanic rocks:A case study of Longfengshan area in Songliao Basin 被引量:1
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作者 XING Jian SHAN Xuanlong +3 位作者 REN Xianjun YI Jian LIU Chaoyang NIU Penghui 《Global Geology》 2022年第2期69-83,共15页
The basin margin slope area of Changling fault depression in Songliao Basin is dominated by intermediate-basic volcanic rocks of Huoshiling Formation,and there is still a lack of in-depth understanding of the developm... The basin margin slope area of Changling fault depression in Songliao Basin is dominated by intermediate-basic volcanic rocks of Huoshiling Formation,and there is still a lack of in-depth understanding of the development pattern and formation mechanism of high-quality reservoirs in intermediate-basic volcanic rocks in this area.Taking the intermediate volcanic rocks in Longfengshan area of Changling fault depression as an example,a comprehensive study was undertaken via core observations,thin section porosity analysis,rock physical property tests,scanning electron microscopy and X-ray diffraction analysis,combined with well log and seismic d ata.As a result,formation mechanism of a high quality reservoir was made clear based on dissolution modification effects of the volcanic rocks,and the development model of the high quality reservoir under t he dual control of lithology and fluid was established.The research shows that the volcanic rocks in this area consist of six lithologies:andesitic hydrothermal breccia,andesite,andesitic volcanic breccia,andesitic tuff,dacitic tuff and sedimentary tuff,which are controlled by structure,eruptive source,eruptive action and palaeotopography.The proximal facies of the volcanic edifice were located on the basin margin,distributed along faults mainly consisting of overflow facies intermixed with eruptive facies,and gradually transformed into thick eruptive facies(middle-source facies)and volcanic sedimentary facies(distal facies).The reservoir space of volcanic rocks was dominated by dissolution pores,which were formed by weathering and dissolution by organic acidic fluids.The thermal debris flow subphase in the middle-source facies of the volcanic edifice had a large amount of easily dissolved volcanic ash,which was close to the source rock in the centre of the basin and was a favourable area for the development of dissolution pores.This study is providing a guide for oil and gas exploration in the intermediate-basic volcanic rocks in the slope of Changling fault depression in Songliao Basin. 展开更多
关键词 Songliao Basin Changliang fault depression intermediate volcanic rock DISSOLUTION RESERVOIR
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CHBMISTRY OF HYODEOXYCHOLIC ACID 5. CONCISE SYNTHESIS OF 25-HYDROXYCHOLESTEROL FROM HYODEOXYCHOLIC ACID, A KEY INTERMEDIATE OF 25-HYDROXYVITAMIN D_3
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作者 Zhong Qi WANG Li Zhong JIANG Wei Shan ZHOU Shanghai Institute of Organic Chemistry, Academia Sinica 345, Lingling Lu, Shanghai 200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第6期409-410,共2页
25-Hydroxycholesterol, which is an important intermediate for the synthesis of 25-hvdroxyvitamin D_3 and 1α, 25-dihydroxyvitamin D_3, was prepared efficiently from hyodeoxycholic acid in 31% overall yield in seven st... 25-Hydroxycholesterol, which is an important intermediate for the synthesis of 25-hvdroxyvitamin D_3 and 1α, 25-dihydroxyvitamin D_3, was prepared efficiently from hyodeoxycholic acid in 31% overall yield in seven steps. 展开更多
关键词 CONCISE SYNTHESIS OF 25-HYDROXYCHOLESTEROL FROM HYODEOXYCHOLIC acid CHBMISTRY OF HYODEOXYCHOLIC acid 5 A KEY intermediate OF 25-HYDROXYVITAMIN D3 CHC
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STUDY ON THE SYNTHESIS OF TETRACYCLIC DITERPENOID 7 Preparation of the Key Intermediate 5 for the Synthesis of Grandiflorenic Acid and its Analogues
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作者 Yun Xing CHENG Wei Shan ZHOU Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,345 Lingling Lu,Shanghai 200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第4期291-294,共4页
The key intermediate 5 for synthesis of the contragestationally active diterpenoid grandiflorenic acid(1)and its analogues 2 and 3 was prepared and an acetyl transposition reaction occurred in the SeO_2 oxida- tion of 8.
关键词 In STUDY ON THE SYNTHESIS OF TETRACYCLIC DITERPENOID 7 Preparation of the Key intermediate 5 for the Synthesis of Grandiflorenic acid and its Analogues
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The effects of temperature and acid number of crude oil on the wettability of acid volcanic reservoir rock from the Hailar Oilfi eld 被引量:5
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作者 Xie Quan He Shunli Pu Wanfeng 《Petroleum Science》 SCIE CAS CSCD 2010年第1期93-99,共7页
Wettability of acid volcanic reservoir rock from the Hailar Oilfield, China, was studied with crude oils of different acid numbers generated from an original crude oil with an acid number of 3.05 mg KOH/g. The modifed... Wettability of acid volcanic reservoir rock from the Hailar Oilfield, China, was studied with crude oils of different acid numbers generated from an original crude oil with an acid number of 3.05 mg KOH/g. The modifed oils and their resultant acid numbers were: A (2.09 mg KOH/g), B (0.75 mg KOH/g), C (0.47 mg KOH/g), D (0.30 mg KOH/g), and E (0.18 mg KOH/g). Contact angles and improved Amott water indexes were measured to study the effects of temperature and acid number on the wettability of the acid volcanic reservoir rock. Experimental results indicated that the wettability was not sensitive to variation in temperature when using the same oil, but the acid number of the crude oil was a key factor in changing the wettability of the rock. The Amott water index, Iw was an exponential function of the acid number, and the Amott water index increased as the acid number decreased (i.e. Amott water index exponentially decreased with the acid number increase). The Iw value of the core saturated with oil A, with an acid number of 2.09 mg KOH/g, ranged from 0.06 to 0.11, which indicated low water wetness. If the acid number of the oil decreased to 0.18 mg KOH/g, the Iw value increased to 0.95, which indicated strong water wetness. The contact angle decreased from 80~ to 35~ when the aid number decreased from 0.75 to 0.18 mg KOH/g, indicating a change towards more water wet conditions. The oil recovery by spontaneous imbibition of water also increased as the acid number of the oil decreased. As an example, at 80 ~C, the recovery of Oil A with an acid number of 2.09 mg KOH/g was only 7.6%, while Oil E with an acid number of 0.18 mg KOH/g produced 56.4%, i.e. an increase of 48.8%. 展开更多
关键词 acid volcanic reservoir rock Amott wettability index wetting angle TEMPERATURE acid number WETTABILITY
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Catastrophic and persistent environmental consequences of an acid crater-lake discharge, Chiginagak Volcano, Alaska
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作者 Janet R. Schaefer William C. Evans +3 位作者 Bronwen Wang William E. Scott Robert G. McGimsey Janet Jorgenson 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期230-231,共2页
关键词 酸性 火山 深湖 地球化学
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The acid lakes and rivers of Copahue Volcano, Argentina
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作者 Johan C. Varekamp 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期229-229,共1页
关键词 火山 活性 同位素 地球化学 稀土元素
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盆地火山岩相研究进展——基性火山熔岩及水下喷发火山岩相新成果
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作者 单玄龙 邹玉洁 +5 位作者 衣健 郝国丽 李昂 石云倩 陆俊杰 李嘉慧 《吉林大学学报(地球科学版)》 CAS CSCD 北大核心 2024年第3期721-734,共14页
火山岩相是火山物质喷发类型、搬运方式和就位环境与状态的总和,划分火山岩相是刻画盆地火山岩分布,寻找火山岩有利储层的基础,对盆地火山岩油气勘探具有重要作用。前人以火山岩的“岩性-组构-成因”为分类依据,建立了盆地火山岩“5相1... 火山岩相是火山物质喷发类型、搬运方式和就位环境与状态的总和,划分火山岩相是刻画盆地火山岩分布,寻找火山岩有利储层的基础,对盆地火山岩油气勘探具有重要作用。前人以火山岩的“岩性-组构-成因”为分类依据,建立了盆地火山岩“5相15亚相”分类方案,极大推动了我国盆地深层火山岩勘探进程。目前,我国大规模的盆地火山岩油气勘探已经走过了20余年的历程,随着勘探的深入对该岩相分类方案进行了不断地完善和丰富:针对基性火山熔岩,建立了基性溢流相,以及板状熔岩流、辫状熔岩流和玻质碎屑岩3种亚相及相模式;针对湖盆水下喷发,建立了水下爆发相,以及气携水下热碎屑流、水携火山高密度流和水下降落3种亚相及相模式,形成了“7相21亚相”的新的分类方案。基性溢流相中,辫状熔岩流亚相储层发育条件最好,玻质碎屑岩亚相次之,板状熔岩流亚相稍差;水下爆发相中,气携水下热碎屑流亚相控制有效储层的空间分布。基性溢流相的建立,克服了基性熔岩因单层厚度薄,钻井和地震亚相刻画困难等问题;水下爆发相的建立,实现了沉积盆地从陆上到水下不同喷发环境火山岩相的准确刻画。两种岩相的建立为进一步探索基性火山熔岩发育区和水下喷发火山碎屑岩发育区储层发育规律,寻找有利储层提供了基础。 展开更多
关键词 火山岩相 基性溢流相 水下爆发相 火山岩储层 盆地
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松辽盆地深层中-基性火山岩有利相带及储层“甜点”逐级识别
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作者 李宁 李瑞磊 +2 位作者 苗贺 曹开芳 田军 《石油与天然气地质》 EI CAS CSCD 北大核心 2024年第3期801-815,共15页
松辽盆地深层下白垩统火石岭组中-基性火山岩广泛发育,岩性-岩相复杂,储层横向非均质性强,储层“甜点”识别难,制约了油气勘探和开发。以查干花地区为例,研究了松辽盆地深层中-基性火山岩岩相及储层特征,提出了火山通道、有利岩相、有... 松辽盆地深层下白垩统火石岭组中-基性火山岩广泛发育,岩性-岩相复杂,储层横向非均质性强,储层“甜点”识别难,制约了油气勘探和开发。以查干花地区为例,研究了松辽盆地深层中-基性火山岩岩相及储层特征,提出了火山通道、有利岩相、有利岩性及储层甜点识别方法。研究表明:①火山岩岩相主要为3相6亚相,优质储层岩性主要为粗粒、细粒凝灰岩和凝灰质砂岩,在近-中源相带中火山爆发相储层最为发育,相带控制了有利岩性凝灰岩的分布区域,物性和含气性是火山岩“甜点”的主要控制因素。②通过分析每个喷发期次的裂缝密度,结合蚂蚁体与地震数据的叠合剖面,识别出了不同喷发期次的火山通道,以判断火山近源相带,再结合火山机构厚度和能量半衰时属性划分中源与远源相带的边界,实现储层“甜点”发育区的定性刻画。③为降低地震反演定量预测中-基性火山岩储层的多解性,优选出低波阻抗表征沉凝灰岩,低密度表征高核磁孔隙度储层,低拉梅常数表征气层,基于此,在叠前反演密度预测孔隙度数据体的基础上,逐级剔除干扰沉凝灰岩、低孔隙度层及非气层,得到较为可靠的火山岩储层“甜点”空间分布预测结果。经验证,预测结果符合有利相带分布规律,且与已钻井气层解释结论吻合。应用有利相带定性认识及逐级定量刻画“甜点”空间分布,部署井取得较好效果,该方法可在深层火山岩“甜点”分布地震预测中广泛推广。 展开更多
关键词 逐级识别 火山通道 有利相带 储层“甜点” 中-基性火山岩 松辽盆地
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气相条件下Criegee中间体与痕量酸碱物种的双分子反应研究进展
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作者 王兴 蒋友凌 +2 位作者 周莉 马嫣 郑军 《环境化学》 CAS CSCD 北大核心 2024年第8期2741-2757,共17页
气相臭氧化反应是不饱和烯烃在大气中重要的降解途径之一.反应会生成一个关键的Criegee中间体,该中间体有非常活跃的反应活性,可以发生单分子分解反应生成羟基自由基和烷氧自由基,也可以与大气中其他化合物发生双分子反应,生成复杂的反... 气相臭氧化反应是不饱和烯烃在大气中重要的降解途径之一.反应会生成一个关键的Criegee中间体,该中间体有非常活跃的反应活性,可以发生单分子分解反应生成羟基自由基和烷氧自由基,也可以与大气中其他化合物发生双分子反应,生成复杂的反应产物.受测量手段的限制和大气丰度的影响,关于Criegee中间体双分子反应的研究主要集中在与H_(2)O、(H_(2)O)2及SO_(2)的反应.大气中的无机酸、有机酸、氨和有机胺是大气中痕量、具有高反应活性的化合物,在维持大气酸碱平衡、新粒子生成及二次有机气溶胶形成过程中发挥重要作用.近年的研究指出,Criegee中间体与这些痕量酸碱气体反应速率接近碰撞极限,并生成低挥发性有机物,颠覆了以往研究中认为的反应可以忽略的结论.结合前人的研究成果,对Criegee中间体双分子反应机理做了简要总结,着重阐述了Criegee中间体与无机酸和有机酸以及与氨和有机胺在大气中的双分子反应过程.从文献的梳理中我们发现Criegee中间体与有机酸和有机胺的双分子反应均可以无势垒发生,并且有低聚产物生成,这些机理的提出对于现有的全球化学传输模型和新粒子形成模型可能有重要影响. 展开更多
关键词 Criegee 中间体 双分子反应 无机酸 有机酸 有机胺.
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瓜蒌皮注射液及其中间体中17种氨基酸含量测定及其变化规律研究 被引量:2
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作者 陶香 张静娴 +7 位作者 胡青 孙健 董莹 丁金国 于泓 沈盈盈 毛秀红 季申 《中成药》 CAS CSCD 北大核心 2024年第3期709-717,共9页
目的测定瓜蒌皮注射液及其中间体中天冬氨酸、谷氨酸、丝氨酸、甘氨酸、苏氨酸、瓜氨酸、精氨酸、丙氨酸、γ-氨基丁酸、酪氨酸、缬氨酸、苯丙氨酸、异亮氨酸、鸟氨酸、亮氨酸、赖氨酸、脯氨酸的含量,并分析其变化规律。方法OPA-FMOC在... 目的测定瓜蒌皮注射液及其中间体中天冬氨酸、谷氨酸、丝氨酸、甘氨酸、苏氨酸、瓜氨酸、精氨酸、丙氨酸、γ-氨基丁酸、酪氨酸、缬氨酸、苯丙氨酸、异亮氨酸、鸟氨酸、亮氨酸、赖氨酸、脯氨酸的含量,并分析其变化规律。方法OPA-FMOC在线衍生化分析采用Waters XBridge C_(18)色谱柱(4.6 mm×100 mm,3.5μm);流动相磷酸盐缓冲液-[甲醇-乙腈-水(45∶45∶10)],梯度洗脱;体积流量1 mL/min;柱温45℃;检测波长262、338 nm。主成分分析、热图分析对10道工序相应中间体的6批样品进行化学模式识别。结果17种氨基酸在各自范围内线性关系良好(R^(2)>0.9980),平均加样回收率83.4%~119.5%,RSD 0.91%~7.94%。相同工序不同批次样品较聚集,不同工序相应中间体聚为3组。醇沉和阳离子交换柱对氨基酸组成影响最大。结论本实验可为瓜蒌皮注射液质量控制的关键因素提供重要参考,以保证终产品的稳定性和均一性。 展开更多
关键词 瓜蒌皮注射液 中间体 氨基酸 含量测定 变化规律 OPA-FMOC在线衍生化 主成分分析 热图分析
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Preparation of Cu nanoparticles with ascorbic acid by aqueous solution reduction method 被引量:7
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作者 刘清明 Takehiro YASUNAMI +1 位作者 Kensuke KURUDA Masazumi OKIDO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第9期2198-2203,共6页
Cu nanoparticles were prepared by reducing Cu2+ ions with ascorbic acid through aqueous solution reduction method. The effects of solution pH and average size of Cu2O particles on the preparation of Cu nanoparticles ... Cu nanoparticles were prepared by reducing Cu2+ ions with ascorbic acid through aqueous solution reduction method. The effects of solution pH and average size of Cu2O particles on the preparation of Cu nanoparticles were investigated. Cu particles were prepared at pH 3, 5 or 7, with the smallest Cu particles obtained at pH 7. However, Cu particles could not be prepared at pH 9 or 11. The average size of Cu2O particles can affect that of Cu particles. Larger Cu2O particles result in larger Cu particles. In addition, experiments were conducted to explore the reaction process by measuring the X-ray diffraction (XRD) patterns of specimens collected at different time points during the reaction. It was found that Cu(OH)2 was initially formed as a precursor, followed by the formation of Cu2O, which was finally reduced to Cu particles. 展开更多
关键词 Cu nanoparticles aqueous solution reduction method ascorbic acid intermediate product
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催化剂酸碱性与催化酯醛缩合性能的关系
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作者 张伟 贾鑫 +3 位作者 王兴永 孙培永 傅送保 姚志龙 《精细化工》 EI CAS CSCD 北大核心 2024年第3期687-696,共10页
以γ-Al_(2)O_(3)和SiO_(2)为载体,采用浸渍法引入不同含量Na^(+)、K^(+)和Cs+碱金属离子,制备了一系列酯醛气相缩合催化剂。利用XRD、BET、NH3-TPD和CO_(2)-TPD对催化剂的结构和表面酸、碱性进行了表征,并以丙酸甲酯与甲醛为原料,考察... 以γ-Al_(2)O_(3)和SiO_(2)为载体,采用浸渍法引入不同含量Na^(+)、K^(+)和Cs+碱金属离子,制备了一系列酯醛气相缩合催化剂。利用XRD、BET、NH3-TPD和CO_(2)-TPD对催化剂的结构和表面酸、碱性进行了表征,并以丙酸甲酯与甲醛为原料,考察了其催化酯醛气相缩合反应性能。结果表明,在0.2 MPa、370℃和质量空速为1.2 h^(-1)的条件下,以10%(以载体SiO_(2)质量为基准,下同)Cs/SiO_(2)为催化剂时,丙酸甲酯转化率最高(41.03%),甲基丙烯酸甲酯选择性为99.20%。在有丰富碱活性中心的前提下,催化剂表面弱碱性位点含量与其催化酯醛气相缩合反应性能呈正相关关系,催化剂表面酸性位点和中强碱性位点的存在会导致催化剂催化活性和选择性的降低。 展开更多
关键词 酯醛缩合 催化剂 酸性 碱性 丙酸甲酯 精细化工中间体
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2-氯酮与Meldrum’s acid的反应研究 被引量:2
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作者 丛志奇 尹炳柱 +2 位作者 金龙一 陈铁 李国雷 《化学试剂》 CAS CSCD 北大核心 2003年第6期321-322,366,共3页
探讨了2-氯(?)酮与Meldrum’s acid在不同条件下的反应结果,合成了化合物2-氧代-3-羧基-1-氧杂薁。并用1HN- MR,13CNMR和IR表征了其结构。
关键词 2-氯Zhuo酮 Meldrum′s acid 亲核试剂 2-氧代-3-羧基-1-氧杂薁 药物中间体
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三氟甲磺酸催化制备环丙烷结构燃料中间体吡唑啉
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作者 张汉杰 曹宇鹏 +2 位作者 蒋榕培 孙海云 方涛 《化学推进剂与高分子材料》 CAS 2024年第5期22-29,共8页
通过实验对腙分子内成环制备环丙烷结构高能燃料中间体吡唑啉的酸催化剂进行了筛选,其中三氟甲磺酸的酸性最强,以其来催化合成3,5,5-三甲基-2-吡唑啉,转化率98%,选择性>99%。吡唑啉高温脱氮制备对应环丙烷结构产物,转化率>95%。此... 通过实验对腙分子内成环制备环丙烷结构高能燃料中间体吡唑啉的酸催化剂进行了筛选,其中三氟甲磺酸的酸性最强,以其来催化合成3,5,5-三甲基-2-吡唑啉,转化率98%,选择性>99%。吡唑啉高温脱氮制备对应环丙烷结构产物,转化率>95%。此外,基于密度泛函理论B3LYP/6-311G(d,p)水平,计算了酸催化腙成环反应机理与位点,表明酸催化可以有效降低反应活化能,促进成环反应。Mulliken电荷分布分析显示,腙的质子化是该反应的关键起始步骤。上述结果表明强酸催化剂有利于加快腙转化为吡唑啉的反应速率,且腙的空间位阻是反应关键因素,空间位阻较小的底物转化率较高。该研究为吡唑啉的合成与环丙烷结构燃料的制备提供了一种可行的方法。 展开更多
关键词 环丙烷 高能燃料 高能中间体 吡唑啉 三氟甲磺酸
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抗癌药中间体2-噻吩甲酸制备新工艺研究
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作者 姜维佳 雷伟 +2 位作者 陈杰 王青 王玉高 《现代化工》 CAS CSCD 北大核心 2024年第6期175-180,共6页
在促进剂K_(2)CO_(3)/TiO_(2)的作用下,通过二氧化碳的羧基化反应成功地将噻吩转化为2-噻吩甲酸,并优化了合成条件,考察了促进剂K_(2)CO_(3)/TiO_(2)的结构、性质对合成路线的影响。结果表明,K_(2)CO_(3)/TiO_(2)起主要促进作用的为表... 在促进剂K_(2)CO_(3)/TiO_(2)的作用下,通过二氧化碳的羧基化反应成功地将噻吩转化为2-噻吩甲酸,并优化了合成条件,考察了促进剂K_(2)CO_(3)/TiO_(2)的结构、性质对合成路线的影响。结果表明,K_(2)CO_(3)/TiO_(2)起主要促进作用的为表面无定型K_(2)CO_(3);考虑到产物的热稳定性,反应温度不宜超过300℃;产物在反应刚开始的1 h内大量生成,此后生成速率急速下降。该研究不仅开发了新颖、环保和高效的2-噻吩甲酸合成路线,还拓展了二氧化碳的高效利用途径。 展开更多
关键词 2-噻吩甲酸 抗癌药中间体 二氧化碳 羧基化 合成
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噻吩-2,3-二羧酸的电合成
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作者 王永琪 孙琪昕 +1 位作者 郑婕 冯柏成 《青岛科技大学学报(自然科学版)》 CAS 2024年第3期69-74,共6页
以3-甲基噻吩为原料,通过电卤化、格氏反应、间接电氧化三步合成目标产物噻吩-2,3-二羧酸。考察了电卤化过程中电流密度、温度对2-溴-3-甲基噻吩收率的影响。在此过程中电卤化试剂采用溴化钠,产品收率可达85.5%且能够更好的满足格氏反... 以3-甲基噻吩为原料,通过电卤化、格氏反应、间接电氧化三步合成目标产物噻吩-2,3-二羧酸。考察了电卤化过程中电流密度、温度对2-溴-3-甲基噻吩收率的影响。在此过程中电卤化试剂采用溴化钠,产品收率可达85.5%且能够更好的满足格氏反应中底物活泼性的考究。通过格氏反应合成了3-甲基-2-噻吩羧酸,主要对其反应时间与收率的关系进行了考察,较优反应时间为6 h,产品收率最高达87.8%。以间接电氧化法合成噻吩-2,3-二羧酸,分别考察了电流密度、电解温度、基质氧化温度、投料比、反应时间等因素对反应的影响,较优工艺下收率为87.6%。噻吩-2,3-二羧酸的整个电合成的过程中均无采用传统有毒有害的卤化剂与氧化剂,对环境友好,三废排放少,且过程简单,产物易分离,能够获得较高的产品收率。 展开更多
关键词 有机电合成 电卤化 格氏反应 噻吩-2 3-二羧酸 医药中间体
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大兴安岭呼中地区玛尼吐组火山岩锆石U-Pb年龄、地球化学特征及地质意义
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作者 于跃江 李慧 +3 位作者 李新鹏 江峰 万太平 卜程丹 《地质论评》 CAS CSCD 北大核心 2024年第4期1483-1496,共14页
大兴安岭北部地区大面积分布中生代火山岩,前人对呼中地区玛尼吐组火山岩研究的较少,本文通过年代学及地球化学等方面的研究,探讨玛尼吐组岩石形成年代、岩浆来源及构造背景。对玛尼吐组中—酸性火山岩进行了系统的LA-ICP-MS锆石U-Pb测... 大兴安岭北部地区大面积分布中生代火山岩,前人对呼中地区玛尼吐组火山岩研究的较少,本文通过年代学及地球化学等方面的研究,探讨玛尼吐组岩石形成年代、岩浆来源及构造背景。对玛尼吐组中—酸性火山岩进行了系统的LA-ICP-MS锆石U-Pb测年,显示同位素年龄为154.5±8.6 Ma,表明形成时代为晚侏罗世。岩石地球化学显示富集Rb、Ba、K、Th、La、Ce、Nd、Hf等元素和轻稀土元素,亏损Sr、Nb、P和Ti等元素,属准铝质—铝质高钾钙碱性岩系。玛尼吐组中—酸性火山岩岩浆可能来源于受俯冲板片流体加入引发下地壳部分熔融,进而发生分离结晶作用。构造背景为古太平洋板块向额尔古纳地块下的俯冲作用形成的活动陆缘环境。 展开更多
关键词 中—酸性火山岩 锆石U-PB年龄 地球化学 大兴安岭呼中地区
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