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Tuning Li/Ni mixing by reactive coating to boost the stability of cobalt-free Ni-rich cathode 被引量:1
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作者 Fanghui Du Xitong Zhang +7 位作者 Yingchao Wang Lei Ding Pengfang Zhang Lingyang Liu Dong Wang Jianzong Man Yuling Chen Yunwu Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期20-29,I0002,共11页
Cobalt-free cathode materials are attractive for their high capacity and low cost,yet they still encounter issues with structural and surface instability.AlPO_(4),in particular,has garnered attention as an effective s... Cobalt-free cathode materials are attractive for their high capacity and low cost,yet they still encounter issues with structural and surface instability.AlPO_(4),in particular,has garnered attention as an effective stabilizer for bulk and surface.However,the impact of interfacial reactions and elemental interdiffusion between AlPO_(4) and LiNi_(0.95)Mn_(0.05)O_(2) upon sintering on the bulk and surface remains elusive.In this study,we demonstrate that during the heat treatment process,AlPO_(4) decomposes,resulting in Al doping into the bulk of the cathode through elemental interdiffusion.Simultaneously,PO_(4)^(3-)reacts with the surface Li of material to form a Li_3PO_(4) coating,inducing lithium deficiency,thereby increasing Li/Ni mixing.The suitable Li/Ni mixing,previously overlooked in AlPO_(4) modification,plays a pivotal role in stabilizing the bulk and surface,exceeding the synergy of Al doping and Li_3PO_(4) coating.The presence of Ni^(2+)ions in the lithium layers contributes to the stabilization of the delithiated structure via a structural pillar effect.Moreover,suitable Li/Ni mixing can stabilize the lattice oxygen and electrode-electrolyte interface by increasing oxygen removal energy and reducing the overlap between the Ni^(3+/4+)e_g and O^(2-)2p orbitals.These findings offer new perspectives for the design of stable cobalt-free cathode materials. 展开更多
关键词 Cobalt-free Ni-rich cathode Li/Ni mixing Al doping Li_(3)PO_(4) coating Lithium-ion batteries
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A nonwoven supported mixed matrix membrane for CH4/N2 separation
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作者 Yuntao Liang Yongjing Wang +2 位作者 Wenbin Feng Jingkai Xu Wei Xiao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第9期101-108,共8页
Efficiently enriching low-concentration CH4 is pivotal for enhancing the utilization of unconventional energy sources and mitigating greenhouse gas emissions.This study focuses on modifying the overall performance of ... Efficiently enriching low-concentration CH4 is pivotal for enhancing the utilization of unconventional energy sources and mitigating greenhouse gas emissions.This study focuses on modifying the overall performance of CH_(4)/N_(2)separation membranes.A novel mixed matrix membrane(MMM)with a reinforced substrate structure was developed through a straightforward dip-coating technique.This MMM incorporates a polytetrafluoroethylene(PTFE)porous membrane as the supporting framework,while a composite of block polymer(styrene-butadiene-styrene)and metal-organic framework(Ni-MOF-74)forms the selective separation layer.Comprehensive characterization of Ni-MOF-74 and the fabricatedmembranes was conducted using X-rays diffraction,scanning electron microscope,Brunauer-Emmett-Teller analysis,and gas permeance tests.The findings indicate a robust integration of the PTFE porous support with the membrane layer,enhancing the mechanical stability of theMMM.Under optimal conditions,the mechanical strength of the PM20 membrane(containing 20%Ni-MOF-74)was observed to be 37.7 MPa,representing remarkable increase compared to the non-reinforcedMMM.Additionally,thePM20membrane exhibited an impressive CH4 permeation rate of 92 barrer(1 barrer﹦3.35×10^(-16)mol·m·m^(-2)·s^(-1)·Pa^(-1))alongside a CH_(4)/N_(2)selectivity of 4.18.These results underscore the MMM's substantial performance and its promising potential in methane enrichment applications. 展开更多
关键词 mixed matrix membrane CH_(4)/N_(2)separation MOF fillers Porous skeleton
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C_(2)H_(2)/CH_(4)燃烧特性实验及反应动力学研究
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作者 刘宇 罗蒙蒙 +3 位作者 田富超 谷午 王凯 梁运涛 《燃烧科学与技术》 CAS CSCD 北大核心 2024年第5期473-480,共8页
随着煤矿开采深度的增加,极易出现瓦斯与煤自燃灾害交织共生现象,增大灾害风险.为阐明煤与瓦斯共生灾害发生时的火焰传播特性,有必要开展煤自燃气体掺混对瓦斯燃烧特性的影响研究.乙炔气体(C_(2)H_(2))是煤高温氧化时产生的主要气体之一... 随着煤矿开采深度的增加,极易出现瓦斯与煤自燃灾害交织共生现象,增大灾害风险.为阐明煤与瓦斯共生灾害发生时的火焰传播特性,有必要开展煤自燃气体掺混对瓦斯燃烧特性的影响研究.乙炔气体(C_(2)H_(2))是煤高温氧化时产生的主要气体之一,甲烷(CH_(4))是瓦斯的主要成分,本文研究了0~2%体积分数C_(2)H_(2)掺混对CH_(4)层流燃烧速度的影响规律.结果表明,随着C_(2)H_(2)体积分数的增加,C_(2)H_(2)/CH_(4)混合燃料层流燃烧速度增大.层流燃烧速度受质热扩散作用、动力学和热力学效应的综合影响,当C_(2)H_(2)体积分数增加至2%时,混合燃料的(αLe)^(1/2)、T_(ad)分别增加了1.54%、2.98%,T_(a)减少了26.93%,说明动力学效应是C_(2)H_(2)促进CH_(4)层流燃烧速度增加的主导因素.由活性自由基体积分数分析可知,随着C_(2)H_(2)体积分数的增加,H、O、OH和CH_(3)等活性自由基体积分数均出现增加趋势,从而促进了CH_(4)的燃烧. 展开更多
关键词 C_(2)H_(2)/CH_(4)混合燃料 层流燃烧速度 动力学效应 敏感性分析 活性自由基
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全氟异丁腈(C_(4)F_(7)N)混合气体研究进展综述
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作者 林莘 陈圣 +2 位作者 高克利 张佳 李爽 《沈阳工业大学学报》 CAS 北大核心 2024年第5期541-556,共16页
全氟异丁腈(C_(4)F_(7)N)作为一种潜在SF 6替代气体,近年来备受电力行业关注。介绍了SF 6环保替代技术路线和发展现状,归纳了C_(4)F_(7)N混合气体的放电参数测量和流注放电仿真研究进展,分析了气隙、沿面绝缘以及局部放电性能,剖析了C_(... 全氟异丁腈(C_(4)F_(7)N)作为一种潜在SF 6替代气体,近年来备受电力行业关注。介绍了SF 6环保替代技术路线和发展现状,归纳了C_(4)F_(7)N混合气体的放电参数测量和流注放电仿真研究进展,分析了气隙、沿面绝缘以及局部放电性能,剖析了C_(4)F_(7)N混合气体的灭弧性能、放电后的分解产物特性以及与固体材料的相容性,并概述了其应用情况,总结了C_(4)F_(7)N混合气体替代SF_(6)气体存在的问题,提出了未来需要研究和关注的重点。 展开更多
关键词 C_(4)F_(7)N混合气体 绝缘性能 气体放电 灭弧性能 放电分解
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Ba_(4)Ti_(13)O_(30)陶瓷的制备及其介电性能表征
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作者 王家强 赵泽颖 金灯仁 《现代化工》 CAS CSCD 北大核心 2024年第5期182-186,193,共6页
利用烧结过程中固相反应产生的额外烧结推动力,在1200℃、常压烧结的条件下,通过混相烧结的方法成功制备了晶粒均匀、致密的纯相Ba_(4)Ti_(13)O_(30)陶瓷,研究了Ba_(4)Ti_(13)O_(30)相的合成规律、烧结性能及其显微结构的演变规律,并表... 利用烧结过程中固相反应产生的额外烧结推动力,在1200℃、常压烧结的条件下,通过混相烧结的方法成功制备了晶粒均匀、致密的纯相Ba_(4)Ti_(13)O_(30)陶瓷,研究了Ba_(4)Ti_(13)O_(30)相的合成规律、烧结性能及其显微结构的演变规律,并表征了Ba4Ti13O30材料的介电性能。结果表明,用固相反应法合成的BaTiO_(3)粉体与TiO_(2)在1150℃下即可合成Ba_(4)Ti_(13)O_(30)相,且在1150~1250℃温度范围内均生成单相。当烧结温度为1200℃时,Ba_(4)Ti_(13)O_(30)陶瓷的相对密度达到最大值95%,此时试样的微波性能最佳,其介电常数和品质因数Q×f分别为40和66273,其品质因数Q×f值远高于文献报道的13000;但当烧结温度提高到1230℃时陶瓷试样体密度略有下降并出现晶粒异常长大的现象,微波性能也随之急剧恶化,这是由其显微结构的变化所致。 展开更多
关键词 Ba_(4)Ti_(13)O_(30)陶瓷 相合成 混相烧结 介电性能 微波性能
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G-C_(3)N_(4)/Zn_(0.3)Cd_(0.7)S光催化剂制备及其去除混合染料污染
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作者 陈炎 李娟娟 +2 位作者 李响 徐蕴 李龙凤 《淮北师范大学学报(自然科学版)》 CAS 2024年第4期29-34,共6页
为利用太阳光光催化去除染料污水中多种染料,通过水热反应,成功制备出x%g-G-C_(3)N_(4)/Zn_(0.3)Cd_(0.7)S光催化剂。在可见光照射下,该催化剂能同时降解染料污水中甲基橙、刚果红、中性红和罗丹明B。5%g-G-C_(3)N_(4)/Zn_(0.3)Cd_(0.7)... 为利用太阳光光催化去除染料污水中多种染料,通过水热反应,成功制备出x%g-G-C_(3)N_(4)/Zn_(0.3)Cd_(0.7)S光催化剂。在可见光照射下,该催化剂能同时降解染料污水中甲基橙、刚果红、中性红和罗丹明B。5%g-G-C_(3)N_(4)/Zn_(0.3)Cd_(0.7)S经过80 min光照,对上述4种染料降解效率分别达到98.4%、98.4%、99.2%和99.3%,远高于单一g-C_(3)N_(4)和Zn_(0.3)Cd_(0.7)S。光催化降解循环实验表明5%g-G-C_(3)N_(4)/Zn_(0.3)Cd_(0.7)S具有良好稳定性。x%g-G-C_(3)N_(4)/Zn_(0.3)Cd_(0.7)S光催化剂在染料废水的净化方面具有潜在应用前景。 展开更多
关键词 g-G-C_(3)N_(4)/Zn_(0.3)Cd_(0.7)S 混合染料 光催化降解 水污染 催化机理
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NaCl/Na_(2)SO_(4)混盐溶液纳滤脱盐分质效果研究
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作者 杜永亮 张光远 +1 位作者 苑宏英 赵冲 《天津城建大学学报》 CAS 2024年第1期40-44,共5页
为探究纳滤技术在工业高盐废水处理中的脱盐分质效果,在实验室搭建的纳滤装置上,采用纳滤膜VNF1-4040,研究了NaCl和Na_(2)SO_(4)混盐溶液的脱盐分质过程,考察了在不同质量浓度比混盐进料条件下膜通量、进料质量浓度、进料温度对纳滤脱... 为探究纳滤技术在工业高盐废水处理中的脱盐分质效果,在实验室搭建的纳滤装置上,采用纳滤膜VNF1-4040,研究了NaCl和Na_(2)SO_(4)混盐溶液的脱盐分质过程,考察了在不同质量浓度比混盐进料条件下膜通量、进料质量浓度、进料温度对纳滤脱盐效果的影响.研究结果表明,在所考察工况条件下,纳滤膜对Na2SO4始终有着良好的脱除效果,截留率保持在97.5%以上.对于质量比为1∶9 NaCl/Na_(2)SO_(4)混盐,其Na_(2)SO_(4)截留率均优于相同运行条件下的其它混盐溶液.膜通量越低,进料质量浓度和进料温度越高,NaCl截留率越低,脱盐效果越好.当膜通量、进料质量浓度和进料温度分别为26 LMH、2 g/L和10℃时,Na_(2)SO_(4)截留率最高,分别为98.41%、98.24%和98.80%.纳滤膜对混盐溶液中NaCl的分质效果较好,产水中NaCl的质量浓度占比保持在96%以上. 展开更多
关键词 纳滤膜 高盐废水 NaCl/Na_(2)SO_(4)混盐 脱盐分质 负截留
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固相法制备Bi_(4)V_(2)O_(11)固体电解质在NH_(3)传感器中的应用
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作者 王政 李跃华 +2 位作者 戴磊 王岭 孟维薇 《陶瓷学报》 CAS 北大核心 2024年第5期1013-1021,共9页
通过固相反应法制备了在中低温下具有高离子导电性的固体电解质Bi_(4)V_(2)O_(11),并以CuV_(2)O_(6)为敏感电极组装成混合电位型NH_(3)传感器。通过X射线衍射仪(XRD)、扫描电子显微镜(SEM)和能谱仪(EDS)分析了固体电解质的相组成和传感... 通过固相反应法制备了在中低温下具有高离子导电性的固体电解质Bi_(4)V_(2)O_(11),并以CuV_(2)O_(6)为敏感电极组装成混合电位型NH_(3)传感器。通过X射线衍射仪(XRD)、扫描电子显微镜(SEM)和能谱仪(EDS)分析了固体电解质的相组成和传感器的微观形貌。结果表明,在中低温(300℃~600℃)下Bi_(4)V_(2)O_(11)的电导率高于传统氧离子导体YSZ。传感器测试结果表明,基于Bi_(4)V_(2)O_(11)作固体电解质CuV_(2)O_(6)作敏感电极的传感器能在300℃~500℃的温度范围内对10 ppm~300 ppm的NH_(3)进行检测,而以YSZ作固体电解质的传感器在300℃~350℃性能下降明显;传感器在400℃下有着最高的灵敏度(-59.15 mV/decade),优于相同条件下以YSZ作固体电解质的传感器(-42.89 mV/decade)。传感器具有稳定的响应,传感器的响应值和NH_(3)浓度的对数值呈现良好的正比例关系。 展开更多
关键词 固体电解质 Bi_(4)V_(2)O_(11) NH_(3)传感器 混合电位型
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基于密度泛函的C_(4)F_(7)N/N_(2)/O_(2)三元混合气体击穿及分解特性分析
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作者 刘提 陈聪 +1 位作者 吴震 陈桓 《工程科学与技术》 EI CAS CSCD 北大核心 2024年第5期127-135,共9页
C_(4)F_(7)N具有优异的绝缘性能和环保特性,是有潜力替代SF_(6)的环保型绝缘气体。目前,主要采用CO_(2)作为C_(4)F_(7)N的缓冲气体,其含量一般大于90%,由于CO_(2)为温室气体,将CO_(2)替换为N_(2)后与C_(4)F_(7)N混合,会使混合气体环保... C_(4)F_(7)N具有优异的绝缘性能和环保特性,是有潜力替代SF_(6)的环保型绝缘气体。目前,主要采用CO_(2)作为C_(4)F_(7)N的缓冲气体,其含量一般大于90%,由于CO_(2)为温室气体,将CO_(2)替换为N_(2)后与C_(4)F_(7)N混合,会使混合气体环保性大大提升。虽然,C_(4)F_(7)N/N_(2)混合气体在放电时可能有固体碳析出情况,严重影响气体绝缘设备正常运行,但是,O_(2)的加入能够改善C_(4)F_(7)N/N_(2)二元混合气体的击穿特性,抑制分解产物的产生。为此,本文基于密度泛函理论计算了O_(2)及C_(4)F_(7)N/N_(2)混合气体的电子亲和能、电负性、不同分子数量的O_(2)和N_(2)与C_(4)F_(7)N气体之间的相互作用能及电荷转移量,得出了C_(4)F_(7)N分子的福井函数、C_(4)F_(7)N/N_(2)/O_(2)各气体分子化学键的解离能,分析了C_(4)F_(7)N与O_(2)放电分解涉及的自由基反应过程,从微观角度研究O_(2)对C_(4)F_(7)N/N_(2)混合气体击穿特性及分解特性的影响。结果表明:相较于N_(2),O_(2)的电子亲和能及电负性更强,加入O_(2)有助于提高C_(4)F_(7)N/N_(2)混合气体的击穿电压。O_(2)-C_(4)F_(7)N的相互作用能约为N_(2)-C_(4)F_(7)N相互作用能的5倍;随着缓冲气体分子数量的增加,缓冲气体与C_(4)F_(7)N之间电荷转移量逐渐增加,使得C_(4)F_(7)N/O_(2)体系中C_(4)F_(7)N得到电子,而C_(4)F_(7)N/N_(2)体系中C_(4)F_(7)N失去电子。C_(4)F_(7)N未发生放电分解时,缓冲气体与C_(4)F_(7)N分子间主要以物理作用为主,O_(2)的加入消耗C_(4)F_(7)N分解产生的CF_(2)·与C·自由基,减少金属电极表面碳单质的附着。综上,O_(2)的加入能够减少碰撞电离,消耗C_(4)F_(7)N分解产生的自由基,抑制分解产物的产生,改善三元混合气体C_(4)F_(7)N/N_(2)/O_(2)的击穿特性及分解特性。 展开更多
关键词 C_(4)F_(7)N/N_(2)混合气体 密度泛函理论 O_(2) 击穿特性 分解特性
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C_(4)F_(7)N-air混合气体在稍不均匀和极不均匀电场中的工频绝缘特性分析
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作者 陈曦 陈炯 +2 位作者 徐年飞 邓云坤 曲佳璐 《高压电器》 CAS CSCD 北大核心 2024年第9期1-10,19,共11页
近年来,作为SF_(6)有效替代气体之一,七氟异丁腈(C_(4)F_(7)N)因其优异的电气性能和物化特性而受到关注与讨论,然而由于C_(4)F_(7)N的液化温度较高,需要与低液化温度的缓冲气体并用。选择空气作为缓冲气体,在稍不均匀电场与极不均匀电场... 近年来,作为SF_(6)有效替代气体之一,七氟异丁腈(C_(4)F_(7)N)因其优异的电气性能和物化特性而受到关注与讨论,然而由于C_(4)F_(7)N的液化温度较高,需要与低液化温度的缓冲气体并用。选择空气作为缓冲气体,在稍不均匀电场与极不均匀电场下,通过工频击穿实验研究气压、混合占比和电极间隙对C_(4)F_(7)N-air混合气体工频击穿电压的影响。结果发现:C_(4)F_(7)N-air混合气体在两个电场下的工频击穿电压随着电极间隙的增大而近似线性增加,在极不均匀电场下,出现明显“驼峰”效应,混合比为8%~16%的C_(4)F_(7)N-air混合气体工频击穿电压可达到同条件下SF_(6)的67%~86%。在稍不均匀电场下,8%C_(4)F_(7)N/92%air混合气体的绝缘强度约为同条件下SF_(6)的0.8倍。混合比为12%~16%的C_(4)F_(7)N-air混合气体具备与SF_(6)相等的工频绝缘强度。总结:与SF_(6)对比,C_(4)F_(7)N占比为8%~16%的C_(4)F_(7)N-air混合气体具备替代SF_(6)气体的潜力。 展开更多
关键词 C_(4)F_(7)N-air混合气体 工频实验 稍不均匀电场 极不均匀电场 工频绝缘特性
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Hot corrosion behavior of Ni–16Cr–xAl based alloys in mixture of Na_2SO_4-NaCl at 600 ℃ 被引量:4
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作者 李维杰 刘咏 +2 位作者 王岩 韩朝 汤慧萍 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2617-2625,共9页
The hot corrosion behaviors of Ni–16Cr–xAl(x=4.5%, 6.8%, 9.0%, mass fraction) based alloys in Na2SO4–25% NaCl molten salts at 600 °C were investigated. The effects of pre-oxidation and Al content on the resi... The hot corrosion behaviors of Ni–16Cr–xAl(x=4.5%, 6.8%, 9.0%, mass fraction) based alloys in Na2SO4–25% NaCl molten salts at 600 °C were investigated. The effects of pre-oxidation and Al content on the resistance to hot corrosion were examined. The hot corrosion resistance of Ni–16Cr–xAl based alloy with Al addition from 4.5% to 9.0% increases with increasing Al content. The alloy with Al content of 9.0% shows the highest hot corrosion resistance among the examined alloys because more β–NiAl phases are obtained to sustain the Al2O3 scale repaired during hot corrosion. Pre-oxidized specimens have a superior hot corrosion resistance compared with the as-cast specimens, due to a protective oxide scale formed after pre-treatment. 展开更多
关键词 Ni–16Cr–xAl based alloys PRE-OXIDATION Na2SO4–25% NaCl mixed salt hot-corrosion mechanism
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热研2号柱花草和热研4号王草混合青贮对其营养成分及发酵品质的影响 被引量:3
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作者 韩建成 吴群 +2 位作者 蔺红玲 徐志军 周汉林 《热带作物学报》 CSCD 北大核心 2023年第4期809-815,共7页
为合理开发和利用热带牧草资源,研究热研2号柱花草和热研4号王草混合青贮对其营养成分及发酵品质的影响,以期筛选出适宜的混合青贮比例,为调制高品质的青贮饲料提供理论依据。本研究将热研4号王草和热研2号柱花草混合青贮比例分别设置为... 为合理开发和利用热带牧草资源,研究热研2号柱花草和热研4号王草混合青贮对其营养成分及发酵品质的影响,以期筛选出适宜的混合青贮比例,为调制高品质的青贮饲料提供理论依据。本研究将热研4号王草和热研2号柱花草混合青贮比例分别设置为100∶0(CK)、85∶15(A_(1))、70∶30(A_(2))、55∶45(A_(3))4组,青贮30 d后开封取样检测。结果表明:A_(2)组混合青贮感官评价最佳,随着热研2号柱花草比例的升高,pH和氨态氮/总氮(NH_(3)-N/TN)值逐渐升高,A_(1)、A_(2)、A_(3)组与CK组差异显著(P<0.05);乳酸(LA)含量逐渐降低,A_(3)组显著低于CK组(P<0.05);各试验组乳酸/乙酸(LA/AA)值均大于2.6;且A_(2)组丁酸(BA)显著低于其他各处理组(P<0.05)。随着热研2号柱花草比例升高,各处理组粗蛋白(CP)、干物质(DM)和粗脂肪(EE)含量随之升高,且显著高于CK组(P<0.05);水溶性碳水化合物(WSC)含量呈上升趋势,且各试验组差异不显著(P>0.05);中性洗涤纤维(NDF)逐渐降低,且各处理组间差异不显著(P>0.05);各试验组酸性洗涤纤维(ADF)显著降低(P<0.05);与CK相比,各处理组粗灰分(Ash)有所下降,且A_(1)、A_(2)、A_(3)组之间差异不显著(P>0.05);总之,热研2号柱花草和热研4号王草混合青贮可提高青贮饲料的发酵品质和营养价值。从发酵品质和营养价值综合考虑,A_(2)组的混合青贮比例最为适宜。 展开更多
关键词 热研2号柱花草 热研4号王草 混合青贮 营养成分 发酵品质
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CuFe_(2)O_(4)改性脱硫渣氧载体与褐煤的反应特性 被引量:2
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作者 王保文 刘同庆 +4 位作者 张港 李炜光 林德顺 王梦家 马晶晶 《化工进展》 EI CAS CSCD 北大核心 2023年第6期2884-2894,共11页
基于烟气脱硫渣采用改进的提纯工艺和优化参数获得高纯度和反应活性的CaSO_(4),以此作为模板剂结合溶胶凝胶燃烧合成法制备了CuFe_(2)O_(4)改性活化并具有“核-壳”结构的CaSO_(4)-CuFe_(2)O_(4)混合氧载体。在固定床反应器上研究了还... 基于烟气脱硫渣采用改进的提纯工艺和优化参数获得高纯度和反应活性的CaSO_(4),以此作为模板剂结合溶胶凝胶燃烧合成法制备了CuFe_(2)O_(4)改性活化并具有“核-壳”结构的CaSO_(4)-CuFe_(2)O_(4)混合氧载体。在固定床反应器上研究了还原反应温度和循环次数作用下自制CaSO_(4)-CuFe_(2)O_(4)混合氧载体与煤化学链燃烧特性,系统研究了CaSO_(4)副反应与CuFe_(2)O_(4)交互作用下不同气相硫的释放和演化。研究表明,改性脱硫渣与煤反应时,CuFe_(2)O_(4)还原产物Cu、FeO通过未反应CaSO_(4)及已还原的CaS形成的熔融界面获得了其中未能利用的晶格氧,实现了本身的原位氧化,不仅明显提高了改性脱硫渣的反应活性,促进了煤的转化,同时也促进了未反应CaSO_(4)中晶格氧的定向传递和梯级利用。进一步,综合考虑煤的碳转化率以及气相硫的释放特性,确定了改性脱硫渣与煤的最佳反应条件为900℃。而循环实验发现,CaSO_(4)-CuFe_(2)O_(4)氧载体在多次循环中CaSO_(4)副反应不能完全抑制,少量气相硫的逸出加之还原氧载体的部分烧结导致反应活性衰减。 展开更多
关键词 化学链燃烧 烟气脱硫渣 CaSO_(4)-CuFe_(2)O_(4)混合氧载体 碳转化 硫原位控制
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PEBA2533/PEG600/CuNaY混合基质膜的制备及对C_(3)H_(6)/C_(2)H_(4)混合气的分离性能
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作者 张茜 王晓东 黄伟 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2023年第4期727-736,共10页
以聚醚嵌段共聚酰胺(PEBA2533)和聚乙二醇(PEG600)共混物为有机基质、自制CuNaY分子筛为添加剂,利用溶液浇注法制备了PEBA2533/PEG600/CuNaY混合基质膜。采用扫描电子显微镜(SEM)、电感耦合等离子体发射光谱(ICP-OES)、衰减全反射傅里... 以聚醚嵌段共聚酰胺(PEBA2533)和聚乙二醇(PEG600)共混物为有机基质、自制CuNaY分子筛为添加剂,利用溶液浇注法制备了PEBA2533/PEG600/CuNaY混合基质膜。采用扫描电子显微镜(SEM)、电感耦合等离子体发射光谱(ICP-OES)、衰减全反射傅里叶红外光谱(ATR-FTIR)及差示扫描量热(DSC)等分析方法对PEBA2533/PEG600/CuNaY混合基质膜进行表征,考察了CuNaY分子筛中Cu^(2+)交换度和含量对混合基质膜微结构和C_(3)H_(6)/C_(2)H_(4)混合气(摩尔比50/50)分离效果的影响。结果表明:CuNaY与PEBA2533/PEG600发生物理混合,并使有机基质链的移动性增强;CuNaY分子筛在混合基质膜中质量分数不大于6%时,其分布均一,与有机基质结合良好;极化能力更强的Cu^(2+)取代Na^(+)提高了混合基质膜的分离性能,Cu^(2+)交换度对C_(3)H_(6)选择性存在最佳值,低温有利于提高C_(3)H_(6)/C_(2)H_(4)选择性。在温度-35℃、压力0.2 MPa的条件下,添加CuNaY分子筛质量分数6%、Cu^(2+)交换度12.90%时制备的混合基质膜对C_(3)H_(6)/C_(2)H_(4)混合气的分离性能最佳,C_(3)H_(6)/C_(2)H_(4)选择性可达10.5,C_(3)H_(6)渗透系数为350 barrer。 展开更多
关键词 PEBA2533/PEG600/CuNaY混合基质膜 C_(3)H_(6)/C_(2)H_(4)混合气 交换度 分离 渗透系数
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B-L model with D_(4)×Z_(4)×Z_(2)symmetry for fermion mass hierarchies and mixings
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作者 V.V.Vien 《Chinese Physics C》 SCIE CAS CSCD 2024年第6期11-30,共20页
We constructed a gauge B-L model with D_(4)×Z_(4)×Z_(2)symmetry to explain the quark and lepton mass hierarchies and their mixings with realistic CP phases via the type-I seesaw mechanism.Six quark mases,thr... We constructed a gauge B-L model with D_(4)×Z_(4)×Z_(2)symmetry to explain the quark and lepton mass hierarchies and their mixings with realistic CP phases via the type-I seesaw mechanism.Six quark mases,three quark mixing angles,and the CP phase in the quark sector take the central values whereas Yukawa couplings in the quark sector are diluted in a range of difference of three orders of magnitude by the perturbation theory at the first order.Concerning the neutrino sector,a small neutrino mass is achieved by the type-I seesaw mechanism.Both inverted and normal neutrino mass hierarchies are consistent with the experimental data.The predicted sum of neutrino masses for normal and inverted hierarchies,the effective neutrino masses,and the Dirac CP phase are also consistent with recently reported limits. 展开更多
关键词 flavor symmetries quark and lepton masses and mixing extensions of electroweak gauge sector neutrino mass and mixing non-standard-model neutrinos right-handed neutrinos D4 discrete symmetry
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MECHANISM ANALYSIS OF THICKNESS EFFECT ON MIXED MODE Ⅰ/Ⅱ FRACTURE OF LC4-CS ALUMINUM ALLOY 被引量:2
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作者 H.R. Dong W.L. Guo 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2004年第3期255-262,共8页
Mixed mode Ⅰ/Ⅱ fracture erperiments of LC4-CS aluminum alloy were conductedby using tension--shear specimens with thicknesses of 2, 4, 8 and 14mm. Fracturemechanisms of thickness effect on mixed mode Ⅰ/Ⅱ fracture ... Mixed mode Ⅰ/Ⅱ fracture erperiments of LC4-CS aluminum alloy were conductedby using tension--shear specimens with thicknesses of 2, 4, 8 and 14mm. Fracturemechanisms of thickness effect on mixed mode Ⅰ/Ⅱ fracture were first examined fromfracture surface morphology to correlate with the macroscopic fracture behavior andstress state. It is found that specimen thickness has a strong influence on mixed modefracture. As thickness varies from thin to thick the macroscopic fracture surfacesappear the characteristics of plane stress state (2mm, 4mm--thick specimen), three--dimensional stress state (8mm--thick specimens), and plane strain state (14mm--thickspecimens), respectively. The specimens of all kinds of thicknesses are typical of ten-sile type failure under mode Ⅰ loading condition and shear type failure under mode Ⅱloading condition. Two distinct features coexist on the fracture surfaces under mixedmode loading conditions, and the corresponding proportion varies with loading mix-ity. Void--growth processes are the failure mechanism in both predominately tensile-and shears--type fractures. The size and depth of dimples on the fracture surface varygreatly with thickness. Therefore, it is extraordinary necessary to take into accountthe thickness effect when a mixed mode fracture criterion is being established. 展开更多
关键词 LC4-CS aluminum alloy mixed mode Ⅰ/Ⅱ fracture thickness effect macroscopic fracture appearance SEM
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C_(4)F_(7)N/CO_(2)混合气体特高压母线通流温升特性研究 被引量:8
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作者 崔兆轩 林莘 +2 位作者 钟建英 姚永其 徐建源 《电工技术学报》 EI CSCD 北大核心 2023年第9期2491-2499,共9页
随着“碳达峰、碳中和”的提出,环保型高压设备的研制迫在眉睫。C_(4)F_(7)N/CO_(2)混合气体作为极具潜力的环保替代气体,目前已经初步应用于高压母线,其通流温升特性作为重要设计指标,尚待深入研究。该文针对1100 kV环保混合气体特高... 随着“碳达峰、碳中和”的提出,环保型高压设备的研制迫在眉睫。C_(4)F_(7)N/CO_(2)混合气体作为极具潜力的环保替代气体,目前已经初步应用于高压母线,其通流温升特性作为重要设计指标,尚待深入研究。该文针对1100 kV环保混合气体特高压母线,构建磁-流-热多物理场耦合数值计算模型,并建立C_(4)F_(7)N/CO_(2)混合气体物性参数数据库;搭建通流温升测量试验平台,理论与试验相结合,对比分析负荷电流、充气压力、混合比、结构尺寸等不同因素对母线温升的影响,提出合理的设计方案。研究结果表明:C_(4)F_(7)N/CO_(2)混合气体的换热能力不及SF_(6),增大充气压力和C_(4)F_(7)N的混合比,可有效提高母线通流能力,但依然达不到SF_(6)的水平,在C_(4)F_(7)N/CO_(2)混合气体母线设计时应注意此问题;影响母线温升最主要的结构尺寸为导体外径,在导体外径与壳体内径间绝缘距离不变的条件下,导体外径增大11.5%,通流能力与原SF_(6)母线基本一致,该结论可应用于后续的母线设计。 展开更多
关键词 C_(4)F_(7)N/CO_(2) 环保混合气体 特高压母线 通流温升特性 多物理场耦合
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Syntheses, Characterization and Biological Activity of Coordination Compounds of 3-Hydroxy-2-methyl-4<i>H</i>-pyran-4-one and Its Mixed Ligand Complexes with 1,2-Diaminocyclohexane
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作者 Temitayo O. Aiyelabola 《Advances in Biological Chemistry》 2021年第3期106-125,共20页
<span style="font-family:Verdana;">Coordination compounds of 3-hydroxy-2-methyl-4</span><i><span style="font-family:Verdana;">H</span></i><span style="fo... <span style="font-family:Verdana;">Coordination compounds of 3-hydroxy-2-methyl-4</span><i><span style="font-family:Verdana;">H</span></i><span style="font-family:Verdana;">-pyran-4-one with </span><span style="font-family:Verdana;">iron(III), cobat(III) and chromium(III) were synthesized with M:L (1:2)</span><span style="font-family:Verdana;">. Mixed ligand coordination compounds of 3-hydroxy-2-methyl-4</span><i><span style="font-family:Verdana;">H</span></i><span style="font-family:Verdana;">-pyran-4-one and 1,2-diaminocyclohexane using the same metal ions were also synthesized </span><b><span style="font-family:Verdana;">M:L1</span></b><span style="font-family:Verdana;">:</span><b><span style="font-family:Verdana;">L2</span></b><span style="font-family:Verdana;"> (1:1:1) where </span><b><span style="font-family:Verdana;">L1</span></b><span style="font-family:Verdana;"> is 3-hydroxy-2-methyl-4</span><i><span style="font-family:Verdana;">H</span></i><span style="font-family:Verdana;">-pyran-4-one and </span><b><span style="font-family:Verdana;">L2</span></b><span style="font-family:Verdana;"> is 1,2-diaminocyclohexane. The coordination compounds obtained were characterized using electronic and infrared spectral analyses, magnetic susceptibility and percentage metal analysis. They were also evaluated for their cytotoxic and antioxidant activities. The result obtained suggested that octahedral geometry was obtained for all the compounds, as a result of additional two molecules of the solvent coordinated to the metal ions. Both the primary and secondary ligands coordinated in a bidentate fashion. The synthesized compounds exhibited moderate cytotoxicity, although none was as active as the standard. The cobalt(III) mixed ligand complex elicited the highest activity. The synthesized compounds all exhibited good to moderate antioxidant activity.</span> 展开更多
关键词 Coordination Compounds Cytotoxicity Antioxidant mixed Ligand Complexes 3-Hydroxy-2-methyl-4H-pyran-4-one 1 2-Diaminocyclohexane
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Physico-Chemical Properties and Catalytic Behavior of LnSrNiO_4 Mixed Oxides for NO Decomposition
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作者 赵震 杨向光 +1 位作者 刘钰 吴越 《Journal of Rare Earths》 SCIE EI CAS CSCD 1998年第1期18-25,共8页
A series of LnSrNiO_4(A_2BO_4, Ln=La, Pr, Nd, Sm, Gd) mixed oxides with K_2NiF_4 structure, in which Asite(Sr) was partly substituted by individual light rare earth element, was prepared. The solid state physicochemic... A series of LnSrNiO_4(A_2BO_4, Ln=La, Pr, Nd, Sm, Gd) mixed oxides with K_2NiF_4 structure, in which Asite(Sr) was partly substituted by individual light rare earth element, was prepared. The solid state physicochemical properties including crystal structure, defect structure, IR spectrum, valence state of Bsite ion, nonstoichiometric oxygen, oxygenous species, the properties of oxidation and reduction etc. as well as the catalytic behavior for NO decomposition on these mixed oxides were investigated. The results show that all of these mixed oxide catalysts have high activity for the direct decomposition of NO(at 900 ℃ the conversion of NO is more than 90%). The effect of the substitution of light rare earth elements at Asite on catalytic behavior for NO decomposition was elucidated. 展开更多
关键词 Rare earths mixed oxides with K_2NiF_4 structure NO decomposition CATALYSIS
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Growth of Mixed Rare Earth Tartrate Crystals (Y_(1-x)Sm_x)_2(C_4H_4O_6)_3·zH_2O from Silica Gels
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作者 Anima Jain and P.N.Kotru(Dept. of Physics, University of Jammu, Jammu-180 001, India)M.L.Kaul (Dept. of Chemistry , University , University of Jammu, Jammu-180 001, India (To whom correspondence should be addressed) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1996年第2期81-88,共8页
Experiments performed on the grwth of mixed crystals of rare earth tartrates (Y1-xSmx)2 (C4H4O6)3.zH2O (0≤x≤1) from silica gels at 35~40℃ and 25~30℃ employing single-diffusion technique. are discussed. The crysta... Experiments performed on the grwth of mixed crystals of rare earth tartrates (Y1-xSmx)2 (C4H4O6)3.zH2O (0≤x≤1) from silica gels at 35~40℃ and 25~30℃ employing single-diffusion technique. are discussed. The crystals maintain spherulitic morphology, irrespective of the value of x, concentration of upper and lower reactants, gel pH, gel age and gel temperature. Formation Of Liesegang rings in this system is a temperature dependent phenomenon. It is shown that with the increase of the value of x the system passes from Liesegangring phenomenon to singlezone phenomenon. Operative mechanism of crystallization in the higher (35~40℃) and lower temperature ranges (25~30℃) is explained. Seeded growth experiments indicate the possibility of increasing the size of the spherulites in the gel medium 展开更多
关键词 SM C4H4O6 Growth of mixed Rare Earth Tartrate Crystals x)Sm_x zH2O from Silica Gels
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