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活性钴引起α-溴代酮的反应
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作者 陈剑协 袁素 +1 位作者 陈伟兴 高济宇 《化学研究与应用》 CAS CSCD 1993年第2期89-92,共4页
近年来,活性钛,活性镍等金属试剂正被用于有机合成并引起人们的关注。最近,对活性钴引起有机反应的研究也日益增多。例如在活性钴试剂作用下,卤代芳烃脱卤偶联得到联苯化合物,α,α—二氯二苯基甲烷脱卤得到四苯乙烯,富马酸与二溴甲烷... 近年来,活性钛,活性镍等金属试剂正被用于有机合成并引起人们的关注。最近,对活性钴引起有机反应的研究也日益增多。例如在活性钴试剂作用下,卤代芳烃脱卤偶联得到联苯化合物,α,α—二氯二苯基甲烷脱卤得到四苯乙烯,富马酸与二溴甲烷可以发生不对称环丙烷化反应等。本文报道活性钴试剂引起α—溴代酮的反应。 展开更多
关键词 活性钴 溴代酮
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影响土壤中钴活性的因素 被引量:5
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作者 蔡祖聪 刘铮 《环境科学学报》 CAS CSSCI CSCD 北大核心 1994年第2期184-190,共7页
用大样本统计分析土壤性质对钴活性的影响及研究改变土壤pH值、有机质和氧化还原状况对钴活性的影响.结果表明,在其它土壤性质不变的情况下,全钴提高,活性钴的数量增加;锰氧化物的作用则相反,在酸性及还原土壤中,土壤pH值、... 用大样本统计分析土壤性质对钴活性的影响及研究改变土壤pH值、有机质和氧化还原状况对钴活性的影响.结果表明,在其它土壤性质不变的情况下,全钴提高,活性钴的数量增加;锰氧化物的作用则相反,在酸性及还原土壤中,土壤pH值、浸提剂pH值对钴的提取量有极显著的影响;在中性和碱性并处于氧化状态的土壤中,影响不显著,增加土壤有机质可以提高活性钴的数量. 展开更多
关键词 土壤 活性钴 因素 影响 统计分析
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合成液体燃料的活性炭负载钴基催化剂的反应性能 被引量:3
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作者 钱炜鑫 庄绪军 +2 位作者 张海涛 应卫勇 房鼎业 《石油化工》 CAS CSCD 北大核心 2011年第4期358-364,共7页
在固定床等温积分反应器中,考察了活性炭负载钴基催化剂(Co/AC)的费托(F—T)合成反应性能,采用BET、H2-TPR和SEM等方法对Co/AC催化剂进行了表征。表征结果显示,Co/AC催化剂孔道属于微孔和中孔的混合结构,可用纯H2还原,还原... 在固定床等温积分反应器中,考察了活性炭负载钴基催化剂(Co/AC)的费托(F—T)合成反应性能,采用BET、H2-TPR和SEM等方法对Co/AC催化剂进行了表征。表征结果显示,Co/AC催化剂孔道属于微孔和中孔的混合结构,可用纯H2还原,还原温度选取350~400℃。实验结果表明,升高反应温度和反应压力、减小气态空速、增加原料气中H2与CO的摩尔比(H2/CO比),有利于提高CO的转化率;升高反应压力、降低反应温度、减小气态空速及原料气H2/CO比有利于高碳烃和高碳醇的生成。Co/AC催化剂用于F—T合成较优的工艺条件为:反应温度230℃,反应压力4.0MPa,原料气H2/CO比2.00,气态空速2000h^-1.在该反应条件下,CO转化率为20.1%,CH4、低碳烃(C2~4)、高碳烃(C5^+)、低碳醇(C1~5OH)及高碳醇(C6^+OH)的选择性分别为19.1%,24.1%,365%,15.8%,4.5%。 展开更多
关键词 液体燃料 费托合成 活性炭负载基催化剂 合成气
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活性炭负载钴基催化剂费托合成本征动力学 被引量:4
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作者 钱炜鑫 张海涛 +1 位作者 应卫勇 房鼎业 《天然气化工—C1化学与化工》 CAS CSCD 北大核心 2012年第2期1-6,共6页
在温度220℃~250℃、压力2.0MPa~4.0MPa、空速2000h-1~3500h-1、n(H2)/n(CO)=1.0~2.5的条件下,在固定床等温积分反应器中研究了活性炭负载钴基催化剂(Co/AC)的本征动力学。结合碳化物机理以及CO插入机理,通过假设不同的基元反应以... 在温度220℃~250℃、压力2.0MPa~4.0MPa、空速2000h-1~3500h-1、n(H2)/n(CO)=1.0~2.5的条件下,在固定床等温积分反应器中研究了活性炭负载钴基催化剂(Co/AC)的本征动力学。结合碳化物机理以及CO插入机理,通过假设不同的基元反应以及速率控制步骤推导得到了不同的本征动力学方程。根据实验测定数据,采用Levenberg-Maquardt算法回归得到模型参数,并通过统计检验以及相对误差分析得到了适宜的Co/AC催化剂费托合成的本征动力学方程。 展开更多
关键词 费托合成 活性炭负载基催化剂 本征动力学
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氧化钴修饰活性炭微波催化降解染料废水的工艺研究 被引量:7
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作者 闻海峰 秦琴 杨琴淋 《水资源与水工程学报》 2013年第1期100-103,共4页
经预处理、超声浸渍、焙烧制备出载钴活性炭。采用热重分析,载钴活性炭的失重温度为410℃,较活性炭提高了30℃;X-射线衍射分析,载钴活性炭在2θ为20.9°、37.1°、43.0°时出现吸收峰,活性炭表面晶型出现了掺杂的CoO立方晶... 经预处理、超声浸渍、焙烧制备出载钴活性炭。采用热重分析,载钴活性炭的失重温度为410℃,较活性炭提高了30℃;X-射线衍射分析,载钴活性炭在2θ为20.9°、37.1°、43.0°时出现吸收峰,活性炭表面晶型出现了掺杂的CoO立方晶系的衍射峰。经电镜扫描分析,CoO颗粒的存在导致载钴活性炭表面缺陷增多。在所定工艺参数下,载钴活性炭催化微波降解染料水溶液10 min,酸性染料及阳离子染料水溶液的脱色率87.95%~96.18%,CODCr去除率78.31%~89.70%,降解过程可用一级化学反应动力学方程拟合。实验表明:氧化钴修饰活性炭在微波催化作用下对染料废水具有良好的降解效果。 展开更多
关键词 微波 活性 染料 化学反应 动力学
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助剂对活性炭负载钴催化剂氨合成活性的影响 被引量:1
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作者 林炳裕 林建新 +1 位作者 王榕 魏可镁 《工业催化》 CAS 2009年第1期38-42,共5页
采用四槽高压连续流动反应器研究了添加助剂Ba、K和Sm对活性炭负载钴催化剂氨合成活性的影响,结果发现,添加助剂Ba、K和Sm可以提高催化剂的氨合成活性,其中,Ba的促进效果最好,Ba与Co物质的量比为0.3时,催化活性最高。在Ba-Co/AC催化剂中... 采用四槽高压连续流动反应器研究了添加助剂Ba、K和Sm对活性炭负载钴催化剂氨合成活性的影响,结果发现,添加助剂Ba、K和Sm可以提高催化剂的氨合成活性,其中,Ba的促进效果最好,Ba与Co物质的量比为0.3时,催化活性最高。在Ba-Co/AC催化剂中,助剂Sm的加入降低了催化剂的氨合成活性,而少量K助剂(K与Co物质的量比为0.25~0.5)可以提高其催化性能,在10 MPa、10 000 h^(-1)和450 ℃条件下,双助剂催化剂的氨合成活性可达120 mmol·(g·h)^(-1),进一步增加K的量,其氨合成活性下降。 展开更多
关键词 无机合成化学 助剂 活性炭负载催化剂 氨合成
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活性炭负载钴–过硫酸盐氧化处理含酚废水的研究
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作者 饶倍仁 吴辉勇 +4 位作者 从军军 张胜军 朱海杰 王鑫蕊 成岳 《环境保护前沿》 2023年第4期914-924,共11页
酚类是一种高毒性的有机物,对人类健康和生态环境都产生了极大的危害,其在氧化反应中产生的中间产物也具有高毒性且难处理、成分复杂、废水量大、色度大,因此有必要对酚类物质的降解进行分析研究。本研究选择活性炭(AC)做载体。通过活... 酚类是一种高毒性的有机物,对人类健康和生态环境都产生了极大的危害,其在氧化反应中产生的中间产物也具有高毒性且难处理、成分复杂、废水量大、色度大,因此有必要对酚类物质的降解进行分析研究。本研究选择活性炭(AC)做载体。通过活性炭负载钴离子,进一步提高过硫酸盐的活性,用X射线分析仪(XRD),扫描电子显微镜(SEM)对活性炭负载钴进行表征分析。通过实验研究钴负载量、活性炭负载钴的投加量、过硫酸钠的投加量、反应时间、反应温度、废水的pH以及废水初始浓度对含酚废水降解效果的影响。结果表明,当钴负载量为6%、活性炭负载钴用量为1.2 g/L、过硫酸钠用量为0.9 g/L、反应时间为100 min、反应温度为50℃、废水的pH为3、废水初始浓度为90 mg/L时,COD的去除率可达95.98%,有可实际操作的意义。 展开更多
关键词 活性炭负载 过硫酸钠 苯酚 高级氧化技术
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载钴活性炭强化电芬顿处理亚甲基蓝废水研究
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作者 康瑾 王琪 +2 位作者 高瞻 熊平 蔡俊雄 《环境科学与技术》 CAS CSCD 北大核心 2023年第12期58-64,共7页
文章以啤酒酵母为原料制备了载钴活性炭(Co/AC)和活性炭(AC,对照材料),用于强化电芬顿处理亚甲基蓝(MB)废水,对体系中存在的吸附和催化降解耦合作用进行了研究。独立吸附反应中,Co/AC对MB的吸附动力学过程和等温吸附过程分别符合准二级... 文章以啤酒酵母为原料制备了载钴活性炭(Co/AC)和活性炭(AC,对照材料),用于强化电芬顿处理亚甲基蓝(MB)废水,对体系中存在的吸附和催化降解耦合作用进行了研究。独立吸附反应中,Co/AC对MB的吸附动力学过程和等温吸附过程分别符合准二级动力学模型和Langmuir方程,其理论饱和吸附容量为232.48 mg/g,低于AC(399.79 mg/g)。电芬顿反应中,Co/AC催化对MB和TOC去除率分别为99.05%、88.57%,高于AC催化的95.95%、68.87%,以及硫酸亚铁催化的35.53%、32.37%。Co/AC优异的催化降解MB性能主要源于其具有更强的促进·OH生成的能力。Co/AC对MB的吸附和催化降解耦合作用过程符合构建的Langmuir-first-order动力学方程。 展开更多
关键词 活性 电芬顿 吸附 催化降解 亚甲基蓝
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ZrO2改性Co/活性炭催化剂对浆态床Fischer-Tropsch合成反应的催化性能 被引量:8
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作者 王涛 丁云杰 +3 位作者 朱何俊 李显明 焦桂萍 林励吾 《石油化工》 EI CAS CSCD 北大核心 2008年第4期323-327,共5页
考察了ZrO2改性Co/活性炭(Zr-Co/AC)催化剂在浆态床反应器中的Fischer-Tropsch合成反应性能及反应条件对催化剂活性和选择性的影响。实验结果表明,适量添加ZrO2助剂可明显提高Co/AC催化剂对Fischer-Tropsch合成反应的催化活性,降低甲烷... 考察了ZrO2改性Co/活性炭(Zr-Co/AC)催化剂在浆态床反应器中的Fischer-Tropsch合成反应性能及反应条件对催化剂活性和选择性的影响。实验结果表明,适量添加ZrO2助剂可明显提高Co/AC催化剂对Fischer-Tropsch合成反应的催化活性,降低甲烷的选择性并提高C5+烃的选择性。当Zr-Co/AC催化剂(Co质量分数为15%)中Zr的质量分数由0增加到6%时,CO的转化率从36.4%增加到67.9%,甲烷选择性从15.4%降低到10.1%,而C5+烃的选择性从71.4%增加到79.3%。当Zr-Co/AC催化剂中Co质量分数为15%、Zr质量分数为2%时,适宜的反应条件为:温度493~503K、压力2.5~3.5MPa、气态空速500~2000h-1、催化剂在浆态液中的体积分数为2.50%。在此条件下催化剂的活性和C5+烃的选择性较高。 展开更多
关键词 二氧化锆助剂 锆-/活性炭催化剂 浆态床反应器 Fischer—Tropsch合成
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双草胺酸钴配合物选择性催化氧化醇类的研究
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作者 蒋雪梅 谌兴华 +1 位作者 潘鑫 吕汪洋 《浙江理工大学学报(自然科学版)》 2017年第4期592-597,共6页
在过氧乙酸活化下,双草胺酸钴配合物([CoⅢ(opba)]-)凭借稳定的化学结构和良好的催化活性,能够在不加入共氧化剂和有机溶剂的条件下氧化苯甲醇类化合物成为醛/酮,选择性达到100%,该催化剂甚至能够偶联初级醇与次级醇成为烯酮。这些反应... 在过氧乙酸活化下,双草胺酸钴配合物([CoⅢ(opba)]-)凭借稳定的化学结构和良好的催化活性,能够在不加入共氧化剂和有机溶剂的条件下氧化苯甲醇类化合物成为醛/酮,选择性达到100%,该催化剂甚至能够偶联初级醇与次级醇成为烯酮。这些反应过程可能为高价钴氧活性种机理,并由于[CoⅢ(opba)]-生成的活性位点具有亲核性,使得该体系对苯环对位带有吸电子基团的苯甲醇类化合物的转化率较高。另外,苯环带有供电子基团的醛类加快了偶联反应的进行,同时降低了反应体系中醛/酮的含量,从而提高了醇类转化率。 展开更多
关键词 选择性氧化 -氧活性 醇类偶联 双草胺酸配合物
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Pd-Co/C催化剂上葡萄糖的催化氧化反应 被引量:7
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作者 宋一兵 余林 +3 位作者 孙长勇 叶飞 方奕文 林维明 《应用化学》 CAS CSCD 北大核心 2002年第10期976-980,共5页
以活性炭作为载体 ,制备了 Pd/C、Pd-Co/C催化剂。活性评价结果表明 ,在 Pd-Co/C催化剂上反应3 h后 ,葡萄糖的转化率达 92 % ,选择性为 94% ,较 Pd/C催化剂的活性和选择性有显著提高。BET和 XPS表征结果表明 ,Pd-Co/C催化剂的良好催化... 以活性炭作为载体 ,制备了 Pd/C、Pd-Co/C催化剂。活性评价结果表明 ,在 Pd-Co/C催化剂上反应3 h后 ,葡萄糖的转化率达 92 % ,选择性为 94% ,较 Pd/C催化剂的活性和选择性有显著提高。BET和 XPS表征结果表明 ,Pd-Co/C催化剂的良好催化活性和选择性是由于 Co的添加及焙烧过程改变了 Pd/C催化剂的表面组成及结构 ,提高了 Pd的还原能力有关。 展开更多
关键词 葡萄糖 Pd-Co/C催化剂 催化氧化 活性炭负载钯催化剂
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Exploration of the active phase of the hydrotalcite-derived cobalt catalyst for HCHO oxidation 被引量:1
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作者 Mengya Lin Xiaolin Yu +2 位作者 Xueqin Yang Xiuyun Ma Maofa Ge 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第5期703-712,共10页
A series of Co-based oxide catalysts were prepared by calcining hydrotalcite precursors in different atmospheres and studied for HCHO catalytic oxidation. The N2-calcined catalyst exhibits enhanced HCHO oxidation and ... A series of Co-based oxide catalysts were prepared by calcining hydrotalcite precursors in different atmospheres and studied for HCHO catalytic oxidation. The N2-calcined catalyst exhibits enhanced HCHO oxidation and superior stability. On the basis of H2-TPR, X-ray photoelectron spectroscopy, and Raman characterizations, this can be ascribed to better redox ability, octahedrally coordinated Co2+ ions derived from the CoO phase, and other surface oxygen species, such as O2– or O–. The extra octahedrally coordinated Co2+ ions may reside in a more open framework site than the inactive tetrahedrally coordinated Co2+ ions. This species of Co2+ can easily make contact with oxygen and oxidize. The surface oxygen species, along with the octahedrally coordinated Co2+ ions, and a part of the Co3+ species constitute the Co2+-oxygen species-Co3+ sites, which enhance the catalytic activities. According to DRIFTS, Co2+-oxygen species-Co3+ makes oxidation of HCHO and conversion of DOM to formate easier. 展开更多
关键词 HCHO Hydrotalcite derivate Active phase Cobalt oxide
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Synergistic Catalytic Action of Cobalt(Ⅱ) Hydroxamates and N-Hydroxyphthalimide in the Aerobic Oxidation of p-Xylene 被引量:1
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作者 JianLIANG JianZhangLI BoZHOU ShengYingQIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第1期111-114,共4页
The catalytic performance of a series of cobalt(Ⅱ) hydroxamates (CoL2) and the synergistic catalytic action of the cobalt complexes combined with N-hydroxyphthalimide (NHPI) in the aerobic oxidation of p-xylene to p-... The catalytic performance of a series of cobalt(Ⅱ) hydroxamates (CoL2) and the synergistic catalytic action of the cobalt complexes combined with N-hydroxyphthalimide (NHPI) in the aerobic oxidation of p-xylene to p-toluic acid (PTA) were investigated. The results showed that the existing synergistic action in the catalytic oxidation can shorten the induction period of the radical reaction and improve the yield of PTA. 展开更多
关键词 Catalysis N-hydroxyphthalimide (NHPI) cobalt(Ⅱ) hydroxamates oxidation of p-xyl- ene.
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Effect of carrier and axial ligand on the photocatalytic activity of cobalt thioporphyrazine 被引量:2
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作者 刘义 周泫沐 +2 位作者 张泽会 张丙广 邓克俭 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期330-336,共7页
The photocatalytic activity of cobalt octakis(butylthio) porphyrazine(CoPz(BuS)8) was assessed through photodegradation of the dye rhodamine B(RhB) in water under irradiation with a Xe lamp and aerated conditi... The photocatalytic activity of cobalt octakis(butylthio) porphyrazine(CoPz(BuS)8) was assessed through photodegradation of the dye rhodamine B(RhB) in water under irradiation with a Xe lamp and aerated conditions.The photocatalytic activity of CoPz(BuS)8 loaded on Al2O3 or SiO2@Fe3O4nanoparticles or coordinated with an axial azide ligand was also investigated.The results demonstrated that the photocatalytic activity of CoPz(BuS)8 loaded on Al2O3 was higher than that loaded on SiO2@Fe3O4.The kinetic curves of RhB degradation in aqueous solutions at different pH indicated the pseudo first-order kinetics of the reaction.The highest degradation rate for CoPz(BuS)8 loaded Al2O3 at pH = 4 after 160 min was 84.6%.However,the advantages of easier separation and recycling as well as the ability to terminate the reaction at any time for the CoPz(BuS)8 loaded SiO2@Fe3O4 cannot be ignored.When electron-rich NaN3 was coordinated with CoPz(BuS)8 as an axial ligand and loaded on Al2O3,the resulting catalyst produced more active oxygen species such as O2^- and HO· to promote the quicker degradation of RhB than that by the other catalysts.For the N3-coordinated CoPz(BuS)8 loaded on Al2O3,the reactions at pH = 4 and 7 distinctly deviated from first-order kinetics,and the degradation rate reached 77.6%after 80 min at pH = 4. 展开更多
关键词 Cobalt thioporphyrazine Photocatalytic activity ALUMINA SiO2@Fe3O4 Axial direction ligand Sodium azide
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Theoretical studies of CO oxidation with lattice oxygen on Co_3O_4 surfaces 被引量:2
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作者 王阳刚 杨小峰 李隽 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第1期193-198,共6页
Low-temperature CO oxidation has attracted extensive interest in heterogeneous catalysis because of the potential applications in fuel cells,air cleaning,and automotive emission reduction.In the present study,theoreti... Low-temperature CO oxidation has attracted extensive interest in heterogeneous catalysis because of the potential applications in fuel cells,air cleaning,and automotive emission reduction.In the present study,theoretical investigations have been performed using density functional theory to elucidate the crystal plane effect and structure sensitivity of Co3O4 nano-catalysts toward catalyzing CO oxidation.It is shown that the surface Co–O ion pairs are the active site for CO oxidation on the Co3O4 surface.Because of stronger CO adsorption and easier removal of lattice oxygen ions,the Co3O4(011)surface is shown to be more reactive for CO oxidation than the Co3O4(001)surface,which is consistent with previous experimental results.By comparing the reaction pathways at different sites on each surface,we have further elucidated the nature of the crystal plane effect on Co3O4 surfaces and attributed the reactivity to the surface reducibility.Our results suggest that CO oxidation catalyzed by Co3O4 nanocrystals has a strong crystal plane effect and structure sensitivity.Lowering the vacancy formation energy of the oxide surface is key for high CO oxidation reactivity. 展开更多
关键词 Carbon monoxide oxidation Cobalt oxide Crystal plane effect Ion-pair active center
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Electroless Co-Zn Surface-Modified Nickel Hydroxide as an Active Material for Pasted Nickel Electrodes
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作者 宋全生 唐致远 +1 位作者 郭鹤桐 CHAN S LI 《Transactions of Tianjin University》 EI CAS 2004年第1期47-53,共7页
Chemically precipitated β type nickel hydroxide powder was surface modified by electroless deposition of Co Zn coatings,and physical properties of both the modified and unmodified nickel hydroxide were characterized ... Chemically precipitated β type nickel hydroxide powder was surface modified by electroless deposition of Co Zn coatings,and physical properties of both the modified and unmodified nickel hydroxide were characterized by scanning electron microscopy (SEM), specific surface area (BET), X ray diffraction (XRD) and X ray photoelectron spectroscopy (XPS). It has been found that Co and Zn components of the surface electroless coatings exist in the oxidized state. Electrochemical performances of pasted nickel electrodes using the modified nickel hydroxide as an active material were investigated, and compared with those of the electrodes prepared with the unmodified nickel hydroxide. Charge/discharge tests show that the modified nickel hydroxide electrodes exhibit better performances in the charge efficiency, specific discharge capacity and active material utilization. Their resistance to swelling with cycling is also superior to that of the unmodified nickel hydroxide electrodes. Cyclic voltammetric (CV) studies indicate that the modified electrodes have a higher electrochemical activity, and the porous pasted nickel electrodes have some distinguished CV characteristics in comparison with those of the thin film nickel electrodes. 展开更多
关键词 nickel hydroxide surface modification electroless deposition of Co Zn pasted nickel electrodes electrochemical performances
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Electrocatalytic hydrogen evolution from water at low overpotentials with cobalt complexes supported by redox-active bipyridyl-NHC donors
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作者 Lizhu Chen Xiaojun Su Jonah W.Jurss 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第12期3187-3194,共8页
Three cobalt complexes bearing tunable,redox-active bipyridyl N-heterocyclic carbene(NHC)-based ligands have been studied for electrocatalytic hydrogen evolution from aqueous solutions.The effect of structural modific... Three cobalt complexes bearing tunable,redox-active bipyridyl N-heterocyclic carbene(NHC)-based ligands have been studied for electrocatalytic hydrogen evolution from aqueous solutions.The effect of structural modifications to the ligand framework is investigated across the catalyst series,which includes a non-macrocyclic derivative(1-Co)and 16-(2-Co)and 15-(3-Co)membered macrocycles.A structure-activity relationship is demonstrated,in which the macrocyclic complexes have greater activity compared to their non-macrocyclic counterpart with the most rigid catalyst,supported by the 15-membered macrocycle,performing best overall.Indeed,3-Co catalyzes H2 evolution from aqueous pH 4 acetate buffer with a Faradaic efficiency of 97%at a low overpotential of 330 mV.Mechanistic studies are consistent with formation of a cobalt-hydride species that is subsequently protonated to evolve H2 via a heterolytic pathway. 展开更多
关键词 Redox-active bipyridyl N-heterocyclic carbene donors Cobalt complex ELECTROCATALYSIS Water splitting Hydrogen evolution
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秸秆及碳化秸秆还田对土壤性质的影响
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作者 潘晶 王蕾 +4 位作者 范琳琳 袁雪梅 宋馨馨 张曦邈 黄琳丽 《沈阳师范大学学报(自然科学版)》 2024年第6期521-527,共7页
秸秆还田是我国秸秆资源合理利用最古老的技术之一。为避免资源浪费,提高秸秆综合利用率,研究了秸秆及碳化秸秆(单一或混合)表层覆盖和深埋2种还田方式对土壤性质和酶活性的影响,结果表明:在表层覆盖还田方式下,秸秆还田处理(T1)的土壤... 秸秆还田是我国秸秆资源合理利用最古老的技术之一。为避免资源浪费,提高秸秆综合利用率,研究了秸秆及碳化秸秆(单一或混合)表层覆盖和深埋2种还田方式对土壤性质和酶活性的影响,结果表明:在表层覆盖还田方式下,秸秆还田处理(T1)的土壤含水量、铵态氮含量、有效磷含量和过氧化氢酶活性较对照(T0)显著提高,分别提高了20.02%,61.86%,54.36%和30.59%。在深埋还田方式下,碳化秸秆还田处理(T5)的土壤硝态氮含量和蔗糖酶活性显著提高,较对照(T0)分别提高了76.85%和138.73%。在实际应用中,可以根据不同的改善目标选择秸秆表层覆盖还田方式或碳化秸秆深埋还田方式。 展开更多
关键词 秸秆还田 碳化秸秆 土壤性质 活性氧化 纳米结构 电容器 电催化
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N,P-dual doped carbon with trace Co and rich edge sites as highly efficient electrocatalyst for oxygen reduction reaction 被引量:10
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作者 Dafeng Yan Lan Guo +3 位作者 Chao Xie Yanyong Wang Yunxiao Li Hao Li 《Science China Materials》 SCIE EI CSCD 2018年第5期679-685,共7页
Oxygen reduction reaction (ORR) is key to fuel cells and metal-air batteries which are considered as the al- ternative clean energy. Various carbon materials have been widely researched as ORR electrocatalysts. It h... Oxygen reduction reaction (ORR) is key to fuel cells and metal-air batteries which are considered as the al- ternative clean energy. Various carbon materials have been widely researched as ORR electrocatalysts. It has been ac- cepted that heteroatom doping and exposure of the edge sites can effectively improve the activity of carbon materials. In this work, we used a simple method to prepare a novel N, P-dual doped carbon-based catalyst with many holes on the surface. In addition, trace level Co doping in the carbon material forming Co-N-C active species can further enhance the ORR performance. On one hand, the doping can adjust the elec- tronic structure of carbon atoms, which would induce more active sites for ORR. And on the other hand, the holes formed on the surface of carbon nanosheets would expose more edge sites and can improve the intrinsic activity of carbon. Due to the heteroatom doping and the exposed edge sites, the pre- pared carbon materials showed highly excellent ORR perfor- mance, dose to that of commercial Pt/C. 展开更多
关键词 ELECTROCATALYSTS oxygen reduction reaction dual-doping Co-N-C edge exposed
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Active catalysts based on cobalt oxide@cobalt/N-C nanocomposites for oxygen reduction reaction in alkaline solutions 被引量:9
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作者 Dekang Huang Yanping Luo Shaohui Li Bingyan Zhang Yan Shen Mingkui Wang 《Nano Research》 SCIE EI CAS CSCD 2014年第7期1054-1064,共11页
Over the past few years, electrocatalysis for the oxygen reduction reaction in alkaline solutions has undergone tremendous advances, and non-precious metal catalysts are of prime interest. In this study, we present a ... Over the past few years, electrocatalysis for the oxygen reduction reaction in alkaline solutions has undergone tremendous advances, and non-precious metal catalysts are of prime interest. In this study, we present a highly promising CoO@Co/N-C (where N-C represents a N-doped carbon material) catalyst, achieving an onset potential of 0.99 V (versus the reversible hydrogen electrode (RHE)) and a limiting current density of 7.07 mA-cm-2 (at 0.3 V versus RHE) at a rotation rate of 2,500 rpm in an O2-saturated 0.1 M KOH solution, comparable to a commercial Pt/C catalyst. The H2--O2 alkaline fuel cell test of CoO@Co/N-C as the cathode reveals a maximum power density of 237 mW.cm 2. Detailed investigation clarifies that a synergistic effect, induced by C-N, Co-N-C, and CoO/Co moieties, is responsible for the bulk of the gain in catalytic activity. 展开更多
关键词 oxygen reduction reaction ELECTROCATALYSIS COO Co/N-C
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