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Enhancing MXene-based supercapacitors:Role of synthesis and 3D architectures
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作者 Wen Siong Poh Wen Jie Yiang +2 位作者 Wee-Jun Ong Pau Loke Show Chuan Yi Foo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期1-26,共26页
MXene has been the limelight for studies on electrode active materials,aiming at developing supercapacitors with boosted energy density to meet the emerging influx of wearable and portable electronic devices.Despite i... MXene has been the limelight for studies on electrode active materials,aiming at developing supercapacitors with boosted energy density to meet the emerging influx of wearable and portable electronic devices.Despite its various desirable properties including intrinsic flexibility,high specific surface area,excellent metallic conductivity and unique abundance of surface functionalities,its full potential for electrochemical performance is hindered by the notorious restacking phenomenon of MXene nanosheets.Ascribed to its two-dimensional(2D)nature and surface functional groups,inevitable Van der Waals interactions drive the agglomeration of nanosheets,ultimately reducing the exposure of electrochemically active sites to the electrolyte,as well as severely lengthening electrolyte ion transport pathways.As a result,energy and power density deteriorate,limiting the application versatility of MXene-based supercapacitors.Constructing 3D architectures using 2D nanosheets presents as a straightforward yet ingenious approach to mitigate the fatal flaws of MXene.However,the sheer number of distinct methodologies reported,thus far,calls for a systematic review that unravels the rationale behind such 3D MXene structural designs.Herein,this review aims to serve this purpose while also scrutinizing the structure–property relationship to correlate such structural modifications to their ensuing electrochemical performance enhancements.Besides,the physicochemical properties of MXene play fundamental roles in determining the effective charge storage capabilities of 3D MXene-based electrodes.This largely depends on different MXene synthesis techniques and synthesis condition variations,hence,elucidated in this review as well.Lastly,the challenges and perspectives for achieving viable commercialization of MXene-based supercapacitor electrodes are highlighted. 展开更多
关键词 MXene 3D architectures synthesis design SUPERCAPACITOR Energy storage
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Sustainable ammonia synthesis:An in-depth review of non-thermal plasma technologies
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作者 Vahid Shahed Gharahshiran Ying Zheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期1-38,共38页
Ammonia serves both as a widely used fertilizer and environmentally friendly energy source due to its high energy density,rich hydrogen content,and emissions-free combustion.Additionally,it offers convenient transport... Ammonia serves both as a widely used fertilizer and environmentally friendly energy source due to its high energy density,rich hydrogen content,and emissions-free combustion.Additionally,it offers convenient transportation and storage as a hydrogen carrier.The dominant method used for large-scale ammonia production is the Haber-Bosch process,which requires high temperatures and pressures and is energy-intensive.However,non-thermal plasma offers an eco-friendly alternative for ammonia synthesis,gaining significant attention.It enables ammonia production at lower temperatures and pressures using plasma technology.This review provides insights into the catalyst and reactor developments,which are pivotal for promoting ammonia efficiency and addressing existing challenges.At first,the reaction kinetics and mechanisms are introduced to gain a comprehensive understanding of the reaction pathways involved in plasma-assisted ammonia synthesis.Thereafter,the enhancement of ammonia synthesis efficiency is discussed by developing and optimizing plasma reactors and effective catalysts.The effect of other feeding sources,such as water and methane,instead of hydrogen is also presented.Finally,the challenges and possible solutions are outlined to facilitate energy-saving and enhance ammonia efficiency in the future. 展开更多
关键词 Nitrogen fixation Ammonia synthesis NH_(3) Non-thermal plasma NI Ru catalyst
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Ultrasonic cavitation-enabled microfluidic approach toward the continuous synthesis of cesium lead halide perovskite nanocrystals 被引量:1
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作者 Mingzhi Li Zhikai Liu +4 位作者 Wang Yao Chao Xu Yangping Yu Mei Yang Guangwen Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第7期32-41,共10页
Ligand assisted reprecipitation(LARP)is a widely used method for cesium lead halide perovskite nanocrystals(NCs)synthesis.Nevertheless,the ultrafast kinetics of LARP,as well as the inefficient transport properties and... Ligand assisted reprecipitation(LARP)is a widely used method for cesium lead halide perovskite nanocrystals(NCs)synthesis.Nevertheless,the ultrafast kinetics of LARP,as well as the inefficient transport properties and discontinuity of batch reactors,challenge the particle size control and experimental repeatability.To address these issues,an ultrasonic cavitation-enabled microfluidic approach was developed to achieve the continuous synthesis of cesium lead halide perovskite via LARP.It was found that the mixing between the good solvent and antisolvent in the microchannel was greatly enhanced by intensive ultrasonic cavitation.The mixing time could be reduced to below 10 ms under the irradiation of 35 W ultrasound.By modulating the mixing degree,LARP was proved to be a mixing-sensitive process.The effects of ultrasonic power,ultrasonic treatment time,total flow rate,water additive,and reprecipitation temperature on the synthesis of CsPbBr_(3) NCs were systematically investigated.As compared to CsPbBr_(3) NCs synthesized in the batch reactor,the sample synthesized via the ultrasonic cavitation-enabled microfluidic approach possessed stronger photoluminescence intensity and better repeatability.Moreover,the ultrasonic cavitation-enabled microfluidic approach could also realize the continuous synthesis of cesium lead halide perovskite NCs with different halide compositions to cover a wide visible spectrum(426-661 nm).The ultrasonic cavitation-enabled microfluidic approach paved the way for the large-scale of high-quality cesium lead halide perovskite NCs. 展开更多
关键词 MICROREACTOR Ultrasound MIXING CsPbBr_(3)nanocrystals synthesis
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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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Recent advances in titanium carbide MXene-based nanotextures with influential effect of synthesis parameters for solar CO_(2)reduction and H_(2)production:A critical review
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作者 Muhammad Tahir Azmat Ali Khan +3 位作者 Sehar Tasleem Rehan Mansoor Areen Sherryna Beenish Tahir 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期295-331,I0008,共38页
Photocatalytic solar to energy conversion is considered an attractive approach for overcoming energy crises and environmental concerns.Recently,titanium carbide(Ti_(3)C_(2))MXenes have been recognized as promising coc... Photocatalytic solar to energy conversion is considered an attractive approach for overcoming energy crises and environmental concerns.Recently,titanium carbide(Ti_(3)C_(2))MXenes have been recognized as promising cocatalysts based on their metallic conductivity,excessive active reaction sites,and enlarged surface area.The current review focuses on the properties and applications of Ti_(3)C_(2)MXenes useful in the field of photocatalysis.More specifically,surface modification of Ti_(3)C_(2)MXenes by varying synthesis parameters to get pure materials and also composites with the role of functional groups towards solar energy conversion applications is highlighted in this review.The effect of etching and oxidizing pathways to get an efficient cocatalyst has been discussed in detail.Considering the significant effect of parameters,optimum synthesis conditions such as etchant type,concentration,time and type of intercalant in both the Ti_(3)C_(2)synthesis approaches for improved photoactivity are discussed.Additionally,the surface modification of Ti_(3)C_(2)through oxidation for TiO2growth on its surface is deliberated with a detailed discussion on etchant type,concentration,etching time,and environmental factors.The optimum oxidation condition,including temperature,time,and environment for thermal treatment of Ti_(3)C_(2),were also included.Lastly,the review summarizes the conclusion and future perspectives for solar energy conversion applications. 展开更多
关键词 Solar to energy conversion Ti_(3)C_(2)nanomaterials Termination groups MXene cocatalyst synthesis parameters
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Low-Temperature Synthesis of Nano-AlN Based on Solid Nitrogen Source by Plasma-Assisted Ball Milling
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作者 Zhuoli Yang Xianbin Hou Leyang Dai 《Journal of Renewable Materials》 SCIE EI 2023年第6期2941-2951,共11页
Plasma-assisted ball milling was carried out on the Al+C3H6N6 system and Al+C_(4)H_(4)N_(4) system,respectively.The phase structure,functional groups and synthesis mechanism were analyzed by XRD and FT-IR,and the diff... Plasma-assisted ball milling was carried out on the Al+C3H6N6 system and Al+C_(4)H_(4)N_(4) system,respectively.The phase structure,functional groups and synthesis mechanism were analyzed by XRD and FT-IR,and the differences in the synthesis process of nano-AlN with different solid nitrogen sources were discussed.The results show that C3H6N6 has a stable triazine ring structure,and its chemical bond is firm and difficult to break,so AlN cannot be synthesized directly by solid-solid reaction at room temperature.However,there are a large number of nitrile groups(-CN)and amino groups(-NH_(2))in C_(4)H_(4)N_(4) molecules.Under the combined action of plasma bombardment and mechanical energy activation,C_(4)H_(4)N_(4) molecules undergo polycondensation and deamination,so that the ball milling tank is filled with a large number of active nitrogen-containing groups such as N=,≡N,etc.These groups and ball milling activated Al can synthesize nano-AlN at room temperature,with a conversion rate of 92%.SEM,DSC/TG analysis showed that the powder obtained by ball milling was formed by soft agglomeration of many fine primary particles about 50–80 nm.The surface morphology of the powder was loose and porous,and it had strong activity.After annealing at 800℃,the conversion rate of the Al+C_(4)H_(4)N_(4) system reached 99%. 展开更多
关键词 Plasma-assisted ball milling solid nitrogen source melamine(C_(3)H_(6)N_(6)) aluminum nitride(AlN) low-temperature synthesis
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新型SF_(6) 环保替代绝缘介质CF_(3)SCF_(3)热动与输运特性
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作者 李兴文 汪冠宇 +3 位作者 唐念 孙东伟 郑晓光 张博雅 《广东电力》 北大核心 2024年第9期3-12,共10页
电力绝缘设备中广泛应用的SF_(6)气体因其极强的温室效应持续危害气候安全,新型环保气体CF_(3)SCF_(3)有望成为替代SF_(6)的绝缘气体。针对这一前景,对比评估CF_(3)SCF_(3)的基础物理特征参数,并基于吉布斯自由能最小化原理以及Chapman-... 电力绝缘设备中广泛应用的SF_(6)气体因其极强的温室效应持续危害气候安全,新型环保气体CF_(3)SCF_(3)有望成为替代SF_(6)的绝缘气体。针对这一前景,对比评估CF_(3)SCF_(3)的基础物理特征参数,并基于吉布斯自由能最小化原理以及Chapman-Enskog理论,研究其作为电力开关设备中灭弧介质的热动与输运性质。结果表明:与大多数环保气体相比,CF_(3)SCF_(3)表现出较好的能量耗散能力与灭弧特性,具备开关装备应用潜力;气压的变化会影响CF_(3)SCF_(3)等离子体中的化学反应进程以及粒子间的相互作用强度,同时改变系统中各类粒子数密度,进而影响其热物理性质;向N 2气体中添加摩尔比25%的CF_(3)SCF_(3)可以将纯N 2在5000 K以下的热耗散参数(质量密度与比热容的乘积)提升约2.5倍以上,且CF_(3)SCF_(3)-N 2混合物的物理特征与CF_(3)SCF_(3)相似,具备作为高气压下灭弧介质的可能。研究结果为开断过程中CF_(3)SCF_(3)环保气体的电弧建模仿真提供了必要基础数据,有助于进一步研究其灭弧特性。 展开更多
关键词 CF_(3)SCF_(3) SF_(6)替代气体 粒子组分 热动属性 输运系数 电弧等离子体
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联苯吡菌胺关键中间体3′,4′-二氯-5-氟-1,1′-联苯-2-胺的合成
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作者 黄晓瑛 尚宇 +2 位作者 王威 王列平 毛明珍 《世界农药》 CAS 2024年第1期38-41,49,共5页
为获得联苯吡菌胺关键中间体3′,4′-二氯-5-氟-1,1′-联苯-2-胺的适合工业化生产工艺路线,对其合成工艺进行了优化。以3,4-二氯溴苯和2-溴-4-氟苯胺为原料,经格氏和Suzuki偶联2步反应合成了3′,4′-二氯-5-氟-1,1′-联苯-2-胺,其结构经... 为获得联苯吡菌胺关键中间体3′,4′-二氯-5-氟-1,1′-联苯-2-胺的适合工业化生产工艺路线,对其合成工艺进行了优化。以3,4-二氯溴苯和2-溴-4-氟苯胺为原料,经格氏和Suzuki偶联2步反应合成了3′,4′-二氯-5-氟-1,1′-联苯-2-胺,其结构经1H NMR、MS表征确证,并对合成条件进行了优化。优化条件下,3′,4′-二氯-5-氟-1,1′-联苯2-胺合成总收率61.9%,纯度98%。该工艺成本低,收率高,具有工业化生产前景。 展开更多
关键词 3′ 4′-二氯-5-氟-1 1′-联苯-2-胺 合成 联苯吡菌胺
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不同表面结构氧化铟催化CO_(2)加氢制甲醇的反应机理
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作者 聂小娃 于笑妍 郭新闻 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2024年第5期1242-1253,共12页
IN_(2)O_(3)对CO_(2)加氢合成甲醇具有较好的催化活性,为了进一步阐明IN_(2)O_(3)的失活机理与甲醇合成的构效关系,选择了立方晶相IN_(2)O_(3)的不同表面,采用密度泛函理论(DFT)研究了H_(2)还原无氧空位的IN_(2)O_(3)完美表面生成氧空... IN_(2)O_(3)对CO_(2)加氢合成甲醇具有较好的催化活性,为了进一步阐明IN_(2)O_(3)的失活机理与甲醇合成的构效关系,选择了立方晶相IN_(2)O_(3)的不同表面,采用密度泛函理论(DFT)研究了H_(2)还原无氧空位的IN_(2)O_(3)完美表面生成氧空位的反应机理,模拟了IN_(2)O_(3)催化剂在氢气作用下失活形成In团簇的微观过程。选择抗烧结性较好的IN_(2)O_(3)(111)阶梯表面,研究了CO_(2)的吸附活化以及甲醇生成的反应机理。结果表明:随着IN_(2)O_(3)表面氧空位数目的增加,H_(2)还原IN_(2)O_(3)的反应能垒升高,H_(2)解离成为氧空位生成的限速步骤;带有缺陷的IN_(2)O_(3)(111)阶梯表面具有较好的反应活性和抗烧结性能;CO_(2)加氢生成HCOO^(*)的反应路径是甲醇合成的优势路线,其中,bi-HCOO^(*)加氢生成bi-H_(2)CO^(*)并同时脱氧填补氧空位的过程为反应的限速步骤。 展开更多
关键词 CO_(2)加氢 甲醇合成 IN_(2)O_(3)催化剂 密度泛函理论 反应机理 催化剂失活机制
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CF_(3)SO_(2)F/N_(2)混合气体的电离特性试验研究 被引量:1
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作者 向志辉 郑宇 +2 位作者 任书波 周文俊 朱太云 《高电压技术》 EI CAS CSCD 北大核心 2024年第3期1331-1339,共9页
为评估CF_(3)SO_(2)F/N_(2)混合气体的绝缘性能,研究了其在电场中的电离特性。通过稳态汤逊实验(SST)测量获得了CF3SO2F摩尔分数分别为10%、20%、30%、40%、100%的CF_(3)SO_(2)F/N_(2)混合气体的有效电离系数和临界约化场强,研究了混合... 为评估CF_(3)SO_(2)F/N_(2)混合气体的绝缘性能,研究了其在电场中的电离特性。通过稳态汤逊实验(SST)测量获得了CF3SO2F摩尔分数分别为10%、20%、30%、40%、100%的CF_(3)SO_(2)F/N_(2)混合气体的有效电离系数和临界约化场强,研究了混合比例、约化场强和电极距离对其电离特性的影响,并比较了CF_(3)SO_(2)F/N_(2)混合气体相对于SF6的绝缘强度。结果表明:CF_(3)SO_(2)F摩尔分数为10%时,CF_(3)SO_(2)F/N_(2)混合气体的电离特性与N_(2)类似;随着CF_(3)SO_(2)F占比增大至20%以上后,CF3SO2F/N2混合气体的电离特性逐步由CF_(3)SO_(2)F主导;CF_(3)SO_(2)F/N_(2)混合气体相对于SF6的理论绝缘强度随着CF_(3)SO_(2)F摩尔分数的增大而增大,40%CF_(3)SO_(2)F/60%N_(2)混合气体的临界约化场强约为SF_(6)的1.01倍,但其对电场变化的敏感程度不如SF6。研究结果可为CF_(3)SO_(2)F/N_(2)混合气体的绝缘强度评估提供理论基础。 展开更多
关键词 CF_(3)SO_(2)F/N_(2)混合气体 SF_(6)替代气体 稳态汤逊实验 临界约化场强 有效电离系数
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基于Boltzmann方程对C_(3)F_(8)/CF_(3)I/CO_(2)三元环保型混合气体的绝缘性能研究
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作者 钟蕊霜 赵谡 +2 位作者 王辉 钱勇 江秀臣 《高压电器》 CAS CSCD 北大核心 2024年第9期46-52,68,共8页
为研究一种新型SF_(6)替代环保绝缘气体介质,采用密度泛函理论(DFT)从微观结构层面上深入地分析C_(3)F_(8)作为一种SF_(6)替代环保绝缘气体的可行性,利用两项近似的Boltzmann方程对300 K下C_(3)F_(8)/CF_(3)I/CO_(2)三元环保混合绝缘气... 为研究一种新型SF_(6)替代环保绝缘气体介质,采用密度泛函理论(DFT)从微观结构层面上深入地分析C_(3)F_(8)作为一种SF_(6)替代环保绝缘气体的可行性,利用两项近似的Boltzmann方程对300 K下C_(3)F_(8)/CF_(3)I/CO_(2)三元环保混合绝缘气体介质的绝缘特性进行了分析,计算三元环保混合气体的电子能量分布函数、电子群参数和协同效应系数等多种微观参数,分析了这些参数随C_(3)F_(8)混合气体比例的变化情况,并与同比例下的c-C_(4)F_(8)/CF_(3)I/CO_(2)三元混合气体的微观参数进行了对比和分析。在约化电场强度E/N低于418 Td时,从扩散系数、电子漂移速度的角度上来看,C_(3)F_(8)三元混合气体的性能优于c-C_(4)F_(8)三元混合气体,在C_(3)F_(8)比例低于7%时,C_(3)F_(8)三元混合气体的绝缘强度高于30%SF_(6)/70%CO_(2)的混合气体,此时的三元混合气体在中低压设备中具有一定的应用潜力。此外,当C_(3)F_(8)气体体积分数为10%时,三元混合气体协同性最好。文中的研究从理论上验证了C_(3)F_(8)/CF_(3)I/CO_(2)替代SF_(6)的可能性。 展开更多
关键词 三元环保型混合气体 C_(3)F_(8)/CF_(3)I/CO_(2) 密度泛函理论 协同效应 绝缘性能
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CF_(3)H和CO_(2)抑制CH_(4)爆炸实验研究
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作者 白洁琪 白纪成 +3 位作者 梁运涛 王琳 宋双林 田富超 《煤矿安全》 CAS 北大核心 2024年第5期122-130,共9页
为对比研究CF_(3)H和CO_(2)对CH_(4)爆炸特性的抑制效果,使用20 L球型爆炸压力测试系统分别测量对比2种抑制剂对CH_(4)在空气中爆炸极限范围的影响;研究了不同体积分数的2种抑制剂对CH_(4)体积分数9.5%爆炸压力参数影响,分析了2种抑制... 为对比研究CF_(3)H和CO_(2)对CH_(4)爆炸特性的抑制效果,使用20 L球型爆炸压力测试系统分别测量对比2种抑制剂对CH_(4)在空气中爆炸极限范围的影响;研究了不同体积分数的2种抑制剂对CH_(4)体积分数9.5%爆炸压力参数影响,分析了2种抑制剂针对CH_(4)在空气中爆炸的爆炸三角形。结果表明:CF_(3)H和CO_(2)均能缩小CH_(4)在空气中的爆炸极限范围,抑制CH_(4)至失爆所需CF_(3)H和CO_(2)体积分数分别为12.5%和21.5%;对比抑制CH_(4)体积分数9.5%的爆炸参数(反应峰值压力和升压速率),10%CF_(3)H的抑爆能力是等量CO_(2)的1.95倍和1.3倍,但是低于体积分数4%的CF_(3)H单独使用时对CH_(4)爆炸存在微弱的促进作用;2种抑制剂作用下的爆炸三角形显示CF_(3)H抑制下的可爆区域面积小于CO_(2),安全区域内CF_(3)H的窒息比是CO_(2)的57%。 展开更多
关键词 CH_(4)爆炸 瓦斯爆炸 CO_(2) CF_(3)H 爆炸极限 抑爆剂 爆炸压力 爆炸三角形
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CF_(3)SO_(2)F及其混合气体电弧等离子体粒子组分与物性参数计算
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作者 柯学 王安阳 +4 位作者 刘伟 颜湘莲 王雯 郭宇铮 王俊 《电工技术学报》 EI CSCD 北大核心 2024年第19期6145-6161,共17页
CF_(3)SO_(2)F是一种有望替代SF_(6)的新型环保绝缘气体,计算CF_(3)SO_(2)F及其混合气体在不同温度下的粒子组成和物性参数对进一步研究其绝缘性质和灭弧能力有重要意义。该文首先深入研究CF_(3)SO_(2)F及其混合气体电弧等离子体粒子组... CF_(3)SO_(2)F是一种有望替代SF_(6)的新型环保绝缘气体,计算CF_(3)SO_(2)F及其混合气体在不同温度下的粒子组成和物性参数对进一步研究其绝缘性质和灭弧能力有重要意义。该文首先深入研究CF_(3)SO_(2)F及其混合气体电弧等离子体粒子组分,并基于吉布斯自由能最小化方法计算得到等离子体在300~30000 K温度范围内的平衡组分;其次根据标准统计热力学关系和Chapman-Enskog方法,在不同气体压力和混合比例下,计算得到等离子体各项热力学参数和输运参数随温度的变化规律;然后探讨了不同缓冲气体对CF_(3)SO_(2)F混合体系的影响,并比较了CF_(3)SO_(2)F与其他常见绝缘气体SF_(6)和C_(4)F_(7)N的相关性质;最后综合分析了CF_(3)SO_(2)F气体的热电弧开断能力。结果表明,在较高的气压下,CF_(3)SO_(2)F气体的分解和电离反应可以被有效抑制;此外,比定压热容分析表明该气体在混合气体中的比例越高,低温区的分解反应越剧烈,高温区的电离反应越平缓;气体种类也会显著影响等离子体的输运特性,不同体系中电导率大小和热导率峰位置等存在较大差异;根据质量密度和比定压热容的乘积(ρc_(p))指标还可以推断CF_(3)SO_(2)F具有较常见绝缘气体C_(4)F_(7)N更强的热电弧开断能力,尽管引入缓冲气体会降低其开断能力,但引入CO_(2)对灭弧性能的负面影响更小。 展开更多
关键词 CF_(3)SO_(2)F 环保绝缘气体 等离子体 粒子组分 物性参数
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新型环保绝缘介质CF_(3)SO_(2)F混合气体电弧等离子体输运参数计算与影响因素分析
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作者 王安阳 柯学 +3 位作者 颜湘莲 郭宇铮 王雯 王俊 《高电压技术》 EI CAS CSCD 北大核心 2024年第9期4261-4271,共11页
绝缘气体输运参数计算对于其绝缘灭弧性能和其他宏观物性研究具有重要意义。首先基于最小吉布斯自由能方法,获得了CF_(3)SO_(2)F混合气体在300~30000 K温度下的粒子组分。在粒子组分的基础上,采用Chapman-Enskog方法求解Boltzmann方程,... 绝缘气体输运参数计算对于其绝缘灭弧性能和其他宏观物性研究具有重要意义。首先基于最小吉布斯自由能方法,获得了CF_(3)SO_(2)F混合气体在300~30000 K温度下的粒子组分。在粒子组分的基础上,采用Chapman-Enskog方法求解Boltzmann方程,计算了0.01~1 MPa压强范围内CF_(3)SO_(2)F混合气体的输运系数(电导率、热导率和黏滞系数),重点考察了气压、混合比例和缓冲气体类别对CF_(3)SO_(2)F混合气体输运参数的影响。结果表明:增大气压会抑制气体解离和电离反应,延缓升温过程对输运系数的影响;增大CF_(3)SO_(2)F混合比例则会直接影响体系主要粒子的相对含量,进而使解离和电离反应的温度发生变化,导致低温区的电导率和中高温区的黏滞系数增大,中高温区的热导率减小;与前两者相比,气体混合类别对输运参数影响较小。此外,相比SF_(6),CF_(3)SO_(2)F混合气体具有更大的热导率和更小的黏滞系数,能够更有效地将焦耳热传递到电弧外从而避免弧后击穿。该研究不仅为CF_(3)SO_(2)F混合气体用于高压电气设备提供一定的指导,也为进一步评估其绝缘和灭弧能力及绝缘气体配置优化提供了必要的数据支撑。 展开更多
关键词 CF_(3)SO_(2)F 环保绝缘气体 SF_(6)替代气体 电弧等离子体 输运参数
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新型环保气体双三氟甲基硫醚的热稳定性研究
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作者 唐念 庞衍泽 +3 位作者 孙东伟 王中奥 张博雅 李兴文 《广东电力》 北大核心 2024年第9期29-35,共7页
为了降低SF_(6)高温室效应对环境的影响,寻找环境友好、性能优异的SF_(6)替代气体很有必要,双三氟甲基硫醚(CF_(3)SCF_(3))因其综合性能良好有望成为新一代SF_(6)替代气体。为了探究CF_(3)SCF_(3)的热稳定性,将CF_(3)SCF_(3)样品充入石... 为了降低SF_(6)高温室效应对环境的影响,寻找环境友好、性能优异的SF_(6)替代气体很有必要,双三氟甲基硫醚(CF_(3)SCF_(3))因其综合性能良好有望成为新一代SF_(6)替代气体。为了探究CF_(3)SCF_(3)的热稳定性,将CF_(3)SCF_(3)样品充入石英管中,使用管式炉加热该气体。在特定温度保持一定时间后,采集气体样品并送入气相色谱质谱联用仪中,提取样品色谱与色谱峰对应的质谱,并在NIST 2017数据库中搜索所获质谱以确定气体成分。研究发现:该气体在450℃时开始生成极少量CF 3 SSCF 3;在500℃时开始出现较为明显的分解;温度继续升高至550℃后,有更多气体分解,并出现了CF 3 CF 3、CS 2、CF 3 SCF 2 CF 3等更多分解产物。由此可知CF_(3)SCF_(3)热稳定性与C_(4)F_(7)N基本相当。研究成果为SF_(6)的环保替代提供了新选择。 展开更多
关键词 SF_(6)替代气体 高通量虚拟筛选 CF_(3)SCF_(3)分子 热稳定性 局部过热
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用于痕量监测Zr^(4+)、Cr_(2)O_(7)^(2-)、Fe^(3+)、HPO_(4)^(2-)和指纹识别的功能化Eu^(3+)/Tb^(3+)配位聚合物荧光探针的构筑
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作者 王思璐 张凤凤 +5 位作者 张成 王潇 唐龙 岳二林 王记江 侯向阳 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第2期441-450,共10页
采用芳香族π共轭及含氮原子有机连接剂,合成同构铽、铕发光配位聚合物(CPs){[Eu(PLIA)_(1.5)(H_(2)O)_(2)]·H_(2)O}_(n)(1)和{[Tb(PLIA)_(1.5)(H_(2)O)_(2)]·H_(2)O}_(n)(2),其中H_(2)PLIA=5-((吡啶-4-基甲基)氧基)苯-1,3-... 采用芳香族π共轭及含氮原子有机连接剂,合成同构铽、铕发光配位聚合物(CPs){[Eu(PLIA)_(1.5)(H_(2)O)_(2)]·H_(2)O}_(n)(1)和{[Tb(PLIA)_(1.5)(H_(2)O)_(2)]·H_(2)O}_(n)(2),其中H_(2)PLIA=5-((吡啶-4-基甲基)氧基)苯-1,3-二甲酸。对合成的配合物进行了结构测定、表征和荧光痕量识别实验研究。2个同构配合物具有理想的三维框架结构,π…π堆积及氢键等弱相互作用增强了其化学稳定性;表征显示配位聚合物1和2具有良好的荧光性质、结晶性、热力学稳定性及结构完整性,可作为荧光传感的材料。1和2对水溶液中的Zr^(4+)、Cr_(2)O_(7)^(2-)和Fe^(3+)、HPO_(4)^(2-)具有选择性好、灵敏度高的荧光识别能力,其检出限分别为0.139μmol·L^(-1)(1,Zr^(4+))、0.626μmol·L^(-1)(1,Cr_(2)O_(7)^(2-))、0.430μmol·L^(-1)(2,Fe^(3+))、1.36μmol·L^(-1)(2,HPO_(4)^(2-))。探究了1和2作为探针的荧光猝灭机理。更有趣的是,1和2具有指纹识别性能,其荧光指纹纹路清晰连贯,细节明显,可被清晰观察。 展开更多
关键词 Eu^(3+)/Tb^(3+)配位聚合物 合成 表征 荧光探针 指纹识别
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Effect of extrusion process on microstructure and mechanical properties of Ni_3Al-B-Cr alloy during self-propagation high-temperature synthesis 被引量:3
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作者 盛立远 奚廷斐 +2 位作者 赖琛 郭建亭 郑玉峰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第3期489-495,共7页
The well-densified Ni3Al-0.5B-5Cr alloy was fabricated by self-propagation high-temperature synthesis and extrusion technique. Microstructure examination shows that the synthesized alloy has fine microstructure and co... The well-densified Ni3Al-0.5B-5Cr alloy was fabricated by self-propagation high-temperature synthesis and extrusion technique. Microstructure examination shows that the synthesized alloy has fine microstructure and contains Ni3Al, Al2O3, Ni3B and Cr3Ni2 phases. Moreover, the self-propagation high-temperature synthesis and extrusion lead to great deformation and recrystallization in the alloy, which helps to refine the microstructure and weaken the misorientation. In addition, the subsequent extrusion procedure redistributes the Al2O3 particles and eliminates the γ-Ni phase. Compared with the alloy synthesized without extrusion, the Ni3Al-0.5B-5Cr alloy fabricated by self-propagation high-temperature synthesis and extrusion has better room temperature mechanical properties, which should be ascribed to the microstructure evolution. 展开更多
关键词 Ni3Al intermetallic compound self-propagation high-temperature synthesis EXTRUSION MICROSTRUCTURE mechanical properties
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A Convenient Synthesis of Trans and Cis-3, 4′, 5-trihydroxystilbene 被引量:2
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作者 王志新 张学景 +1 位作者 周玥 邹永 《Journal of Chinese Pharmaceutical Sciences》 CAS 2005年第4期204-208,共5页
Aim To synthesize trans and cis-3, 4′, 5-trihydroxystilbene by a new convenient route. Methods The reaction of 3, 5-dimethoxybenzaldehyde (3) and 4-methoxy phenylacetonitrile (4) formed the stilbene skeleton. Aft... Aim To synthesize trans and cis-3, 4′, 5-trihydroxystilbene by a new convenient route. Methods The reaction of 3, 5-dimethoxybenzaldehyde (3) and 4-methoxy phenylacetonitrile (4) formed the stilbene skeleton. After hydrolyzation, decarboxylation, and demethylation, we obtained trans-3, 4′, 5-trihydroxystilbene (resveratrol), which can be converted to its cis-isomer by photochemical isomerization. Results Starting from 3 and 4, trans and cis-3, 4′, 5-trihydroxystilbene were synthesized, respectively. Conclusion A facile method for the synthesis of trans and cis-hydroxystilbenes from readily available materials was established. 展开更多
关键词 3 4′ 5-trihydroxystilbene synthesis ISOMERIZATION
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One-step hydrothermal synthesis of Cu-SAPO-34/cordierite and its catalytic performance on NO_x removal from diesel vehicles 被引量:2
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作者 王建成 陈影 +3 位作者 唐磊 鲍卫仁 常丽萍 韩丽娜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第11期3330-3336,共7页
Cu-SAPO-34/cordierite catalysts were prepared via one-step hydrothermal synthesis method and their performances to remove NO x from the diesel vehicle exhaust were evaluated. The morphology, structure, Cu content and ... Cu-SAPO-34/cordierite catalysts were prepared via one-step hydrothermal synthesis method and their performances to remove NO x from the diesel vehicle exhaust were evaluated. The morphology, structure, Cu content and valence state were characterized by SEM, XRD, ICP and XPS, respectively. The experimental results show the active component Cu of the catalysts via in situ synthesis could significantly improve the selective catalytic reduction (SCR) activities of NOx and the optimal Cu content is in the range of 0.30%-0.40%(mass fraction). No N 2 O is detected by gas chromatograph (GC) during the evaluation process, which implies that NOx is almost entirely converted to N2 over Cu-SAPO-34/cordierite catalyst. The conversion rate of NOx to N2 by NH3 over catalyst could almost be up to 100%in the temperature range of 300-670 ℃with a space velocity of 12000 h-1 and it is still more than 60% at 300-620 ℃ under 36000 h-1. The catalysts also show the good hydrothermal and chemical stability at the atmosphere with H 2 O. 展开更多
关键词 in situ synthesis Cu-SAPO-34/cordierite NOx selective catalyst reduction NH3 diesel vehicle exhaust
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Framework-solvent interactional mechanism and effect of NMP/DMF on solvothermal synthesis of [Zn_4O(BDC)_3]_8 被引量:3
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作者 吴争平 王明雪 +4 位作者 周丽姣 尹周澜 谈进 张锦玲 陈启元 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第11期3722-3731,共10页
In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) o... In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) or N-methyl- 2-pyrrolidone(NMP) on solvothermal synthesis of [Zn4O(BDC)3]8 were investigated through a combined DFT and experimental study. XRD and SEM showed that the absorbability of NMP in the pore of [Zn4O(BDC)3]8 was weaker than that of DMF. The thermal decomposition temperature of [Zn4O(BDC)3]8 synthesized in DMF was higher than that in NMP according to TG and FT-IR. In addition, the nitrogen sorption isotherms indicated that NMP improved gas sorption property of [Zn4O(BDC)3]8. The COSMO optimized calculations indicated that the total energy of Zn4O(BDC)3 in NMP was higher than that in DMF, and compared with non-solvent system, the charge of zinc atoms decreased and the charge value was the smallest in NMP. Furthermore, the interaction of DMF, NMP or DEF in [Zn4O(BDC)3]8 crystal model was calculated by DFT method. The results suggested that NMP should be easier to be removed from pore of materials than DMF from the point of view of energy state. It can be concluded that NMP was a favorable solvent to synthesize [Zn4O(BDC)3]8 and the microscopic mechanism was that the binding force between Zn4O(BDC)3 and NMP molecule was weaker than DMF. 展开更多
关键词 solvothermal synthesis [Zn4O(BDC)3]8 N-METHYL-2-PYRROLIDONE interactional mechanism COSMO solvation model density functional method
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