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Mechanism of CeO_(2) synthesized by thermal decomposition of Ce-MOF and its performance of benzene catalytic combustion

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Journal of Rare Earths 2021年第7期39卷 790-796,I0002页

作者： Jie Zheng Zhuo Wang Zhu Chen shufeng zuo Zhejiang Key Laboratory of Alternative Technologies for Fine Chemicals Process Shaoxing UniversityShaoxing 312000China

In this paper,the formation mechanism of mesoporous CeO_(2) synthesized by thermal decomposition of Ce-MOF and its performance of benzene catalytic combustion,as well as the structure-activity relationship between them were studied in depth.The self-assembly process and physicochemical properties of CeO_(2) were characterized by thermogravimetry analysis,powder X-ray diffraction,N2 adsorption/desorption,high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy techniques.Characterization results show that Ce-MOF is completely decomposed into pure mesoporous CeO_(2) when the decomposition temperature is higher than 400℃.At this threshold temperature,CeO_(2)(400) has the largest specific surface area and pore volume of 114 m^(2)/g and 0.152 cm^(3)/g,respectively.CeO_(2)(400) exhibits very high catalytic activity for benzene combustion,which can completely catalyze the degradation of benzene at 260℃.Meanwhile,the mesoporous CeO_(2)(400) supported Pt nanocrystalline catalysts were prepared by high temperature solution-phase reduction method.Pt/CeO_(2)(400)can completely degrade benzene at about 200℃ and represents high durability and good waterresistance for benzene combustion during 100 h of continuous reaction.

关键词： Thermal decomposition Ce-MOF Mechanism Structure-effect relationship Benzene Catalytic combustion

MCM-41 supported nano-sized CuO-CeO2 for catalytic combustion of chlorobenzene

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Journal of Rare Earths 2020年第9期38卷 933-940,I0001页

作者： Jie Zheng Zhu Chen Jianfei Fang Zhuo Wang shufeng zuo Zhejiang Key Laboratory of Alternative Technologies for Fine Chemicals Process Shaoxing UniversityShaoxing 312000China Quality and Technical Supervision Inspection Center of Yongkang Yongkang 321300China

In this paper,MCM-41 was synthesized by a soft template technique and MCM-41 supported CuO-CeO2 nano-sized catalysts with different Cu/Ce molar ratios were prepared by a deposition-precipitation method.N2 adsorption,HRTEM-EDS,H2-TPR,XPS characterization,as well as catalytic activity and durability tests for the catalytic combustion of chlorobenzene(CB)were conducted to explore the relationship between the structure and catalytic performance of the catalysts.It is revealed that cuCe(6:1)/MCM-41 has the highest activity and can completely catalyze the degradation of CB at 260℃.The reasons for the high activity of the catalysts are as follows:MCM-41,a type of mesoporous material which has large pore size and large specific surface area,is suitable as a catalyst carrier.The average diameter of nano-sized CuO and CeO2 particles is about 3-5 nm and adding CeO2 improves the dispersion of active component CuO,which are highly and evenly dispersed on the surface of MCM-41.Characterization results also explain why MCM-41 supported CuO-CeO2 with appropriate proportion can highly enhance the catalytic activity.The reason is that CeO2 acting as an oxygen-rich material can improve the mobility of oxygen species through continuous redox between Ce4^+and Ce3^+,and improve the catalytic performance of CuO for CB combustion.Besides,CuCe(6:1)/MCM-41 also displays good durability for CB combustion,both in the humid condition and in the presence of benzene,making it a promising catalytic material for the elimination of chlorinated VOCs.

关键词： CuO-CeO2 MCM-41 Nano-sized Chlorobenzene Catalytic combustion Rare earths

Ce-modified AlZr pillared clays supported-transition metals for catalytic combustion of chlorobenzene

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Journal of Rare Earths 2018年第11期36卷 1169-1174页

作者： Binbin Feng Yingxi Wei Yingnan Qiu shufeng zuo Na Ye Zhejiang Key Laboratory of Alternative Technologies for Fine Chemicals Process Shaoxing University

In this article, we provided a one-step hydrothermal method to prepare composite AIZr pillaring agents, and synthesized AlZr-pillared clays （AIZr-PILC） via ion exchange. Compared with conventional methods, our method successfully shortened synthetic routes and greatly reduced consumption of the materials. Then, A1Zr-PILC-supported manganese and cerium oxide catalysts were obtained by impregnation method. The compositions and properties of these catalysts were characterized by some technical means. The energy dispersive X-ray spectroscopy clearly shows the existence of Mn, Ce, and O, which indicates the successful loading of the active components on the surface of AIZr-PILC. Meanwhile, the results of X- ray diffraction （XRD） and N2 adsorption experiments demonstrate that the synthesized A1Zr-PILC out- performs the raw clays （Na-mmt） and mononuclear AI-PILC in the catalytic combustion of chloroben- zene. XRD and high-resolution transmission electron microscopy also proves that the high activity of them is related to the high dispersion of the oxides and the exposure of more active sites. H2-temper- ature-programmed reduction shows that cerium can promote the redox cycles of the manganese system through the strong interactions between MnO2, CeO2 and AIZr-PILC. In particular, MnCe（9：1 ）/AIZr-PILC shows the best catalytic activity in the catalytic combustion of chlorobenzene.

关键词： Montmorillonite AIZr-PILC Mn Ce based catalysts Catalytic combustion Chlorobenzene Rare earths

高碳磨球钢中Ds类夹杂物的形成机理及工业控制

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中国冶金 2024年第3期34卷 113-121页

作者：戚泽鑫王锦刘威杨树峰李京社左小坦北京科技大学冶金与生态工程学院北京100083 北京科技大学钢铁冶金新技术国家重点实验室北京100083 芜湖新兴铸管有限责任公司安徽芜湖241000

Ds类非金属夹杂物尺寸大、延展性差,严重影响TL-1D磨球钢疲劳寿命等关键性能指标。对某企业TL-1D磨球钢进行全流程取样分析,结果表明该企业此钢种Ds类非金属夹杂物超标,且该钢种中的Ds类非金属夹杂物主要为Al_(2)O_(3)-CaO-MgO-CaS,在L... 详细信息

Ds类非金属夹杂物尺寸大、延展性差,严重影响TL-1D磨球钢疲劳寿命等关键性能指标。对某企业TL-1D磨球钢进行全流程取样分析,结果表明该企业此钢种Ds类非金属夹杂物超标,且该钢种中的Ds类非金属夹杂物主要为Al_(2)O_(3)-CaO-MgO-CaS,在LF精炼钙处理后大量出现。总结出Ds类夹杂物形成机理为,首先以Al_(2)O_(3)为中心开始形核,之后其与钢液中[Mg]和[Ca]结合并长大形成CaO-Al_(2)O_(3)-MgO球状夹杂物,最后球状夹杂物外层与CaS结合形成Al_(2)O_(3)-CaO-MgO-CaS包裹体。工业试验结果证实,钙处理不利于TL-1D钢中Ds类非金属夹杂物的控制,会造成夹杂物尺寸增大,由此提出在TL-1D磨球钢生产精炼环节进行非钙处理的生产工艺方案。试验结果表明,钢液中钙含量处于饱和状态,优化后精炼渣成分趋于液相区,提升了精炼环节精炼渣系对夹杂物的软熔吸附性能,提高了Ds类非金属夹杂物上浮至渣层时的吸附去除率,最终使连铸坯的初检合格率由95.4%提高至97.0%。研究结果对磨球钢工业生产具有参考价值。

关键词：磨球钢非金属夹杂物洁净度非钙处理工业试验

血浆D-二聚体、血栓调节蛋白与上皮性卵巢癌肿瘤细胞减灭术后铂类药物化疗敏感性的关系

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中国性科学 2024年第4期33卷 109-113页

作者：张晓欲左金玲董娜高淑凤唐山市妇幼保健院妇科河北唐山063000 唐山市妇幼保健院产科河北唐山063000

目的分析血浆D-二聚体(D-D)、血栓调节蛋白(TM)与上皮性卵巢癌肿瘤细胞减灭术后铂类药物化疗敏感性的关系。方法选取2019年6月至2022年5月唐山市妇幼保健院收治的137例行铂类药物化疗的上皮性卵巢癌患者作为研究对象,均完成肿瘤减灭术,... 详细信息

目的分析血浆D-二聚体(D-D)、血栓调节蛋白(TM)与上皮性卵巢癌肿瘤细胞减灭术后铂类药物化疗敏感性的关系。方法选取2019年6月至2022年5月唐山市妇幼保健院收治的137例行铂类药物化疗的上皮性卵巢癌患者作为研究对象,均完成肿瘤减灭术,在化疗前进行血液检查,检查项目包括肿瘤标志物、血浆D-D、TM及相关指标。根据化疗结束后复发时间定义复发类型,复发时间<6个月定义为铂耐药复发,反之定义为铂敏感复发,采用Cox回归分析血浆D-D、TM对上皮性卵巢癌肿瘤细胞减灭术后铂耐药复发的影响。结果137例患者成功随访6个月,其中25例在随访6个月内肿瘤复发,铂耐药复发率为18.25%。铂耐药患者国际妇产科联盟(FIGO)分期Ⅳ期、分化程度G_(3)级、手术满意度R1比例高于铂敏感患者,血清糖类抗原125(CA125)、人附睾蛋白4(HE4)、血浆D-D、TM表达高于铂敏感患者(P<0.05)。Cox回归分析结果显示,G_(3)级分化程度、手术满意度R1、血清CA125、HE4及血浆D-D、TM表达上调是上皮性卵巢癌铂耐药复发的影响因素(P<0.05)。结论血浆D-D、TM表达上调与上皮性卵巢癌铂耐药复发风险增加有关,铂类药物化疗前的血浆D-D、TM表达对于评估铂耐药复发风险具有一定意义。

关键词：上皮性卵巢癌铂类化疗 D-二聚体血栓调节蛋白化疗敏感性

Remarkable mechanochromism and force-induced thermally activated delayed fluorescence enhancement from white-light-emitting organic luminogens with aggregation-induced emission

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Chinese Chemical Letters 2022年第10期33卷 4536-4540页

作者： Yitao Zheng Lingqi zuo Letian Zhang Zihao Huang shufeng Li Zhan Yang Zhu Mao Suilian Luo Cong Liu Fengqiang Sun Guang Shi Zhenguo Chi Bingjia Xu Key Laboratory of Theoretical Chemistry of Environment Ministry of Education/School of ChemistrySouth China Normal UniversityGuangzhou 510006China State Key Laboratory of Optoelectronic Materials and Technologies(Sun Yat-sen University) Guangzhou 510275China School of Chemistry Sun Yat-sen UniversityGuangzhou 510275China Shenzhen Institute of Advanced Electronic Materials Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

The development of organic materials with white-light emission and thermally activated delayed fluorescence(TADF)properties in the solid state remain a challenge.Herein,a series of white-light-emitting organic luminogens have been developed and are found to show aggregation-induced delayed fluorescence(AIDF)characteristics.The AIDF emitters present dual-emission consisted of prompt fluorescence and TADF in the crystalline state.Their white-light emissions can be easily tuned by altering the chemical structure and connecting position of the heterocyclic aromatic substituent.Under the stimuli of mechanical force and solvent vapor,the compounds exhibit remarkable and reversible mechanochromism,in which their emission colors are switchable between white and yellow.Upon grinding,they also display linearly tunable luminescence colors,as well as force-induced TADF enhancement,which may be associated with the more compact molecular packing and the restriction of intramolecular motions.The results from time-resolved emission scanning and theoretical calculation suggest that the dual-emission of the AIDF luminogens likely results from the twisted intramolecular charge transfer transitions of the molecules,and the reversible mechanochromism properties probably stem from the interconversion of the quasi-axial and the quasi-equatorial conformations.

关键词： White-light emission Thermally activated delayed fluorescence Aggregation-induced delayed fluorescence mechanochromism Force-induced emission enhancement

MnCo改性的MCM-41催化剂用于氯苯催化燃烧的研究（英文）

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Chinese Journal of Catalysis 2018年第4期39卷 849-856页

作者：成珍李敬荣杨鹏左树锋绍兴文理学院浙江省精细化学品传统工艺替代技术研究重点实验室浙江绍兴312000

含氯挥发性有机化合物(CVOCs)是对人体健康和环境危害极大的有机化合物.常见的有二氯乙烷、三氯乙烯、三氯甲烷、四氯化碳和氯苯等.有些CVOCs是"三致"(致畸、致癌、致突变)物质,有些少量进入大气就能破坏臭氧层,亦或与臭氧等形成光化学... 详细信息

含氯挥发性有机化合物(CVOCs)是对人体健康和环境危害极大的有机化合物.常见的有二氯乙烷、三氯乙烯、三氯甲烷、四氯化碳和氯苯等.有些CVOCs是"三致"(致畸、致癌、致突变)物质,有些少量进入大气就能破坏臭氧层,亦或与臭氧等形成光化学烟雾,引起全球变暖.因此,对于其消除迫在眉睫.CVOCs通常采用高温直接燃烧、吸附、光催化氧化和催化燃烧等方法降解.其中,催化燃烧是非常有效的.我们选择氯苯作为CVOCs探针分子是因其不仅存在于农药和化工产品中,在室内环境中也大量存在,而负载贵金属和非贵金属型催化剂可用于其催化降解.贵金属催化剂价格高而且易氯中毒,但过渡金属催化剂价格低且抗失活,因而是不错的选择.通常过渡金属催化剂使用V_2O_5,Cr_2O_3,MnO_2,Co_3O_4及NiO等活性组分,而Mn和Co氧化物有较好活性且没有环境污染,常用作活性组分.另外,MCM-41是有序介孔硅酸盐和硅铝酸盐家族中M41S的一员,具有高的比表面积和较窄的孔径分布,常用作催化剂的载体.我们利用具有大比表面积、大孔径的MCM-41作为载体,采用浸渍法负载MnO_x,CoO_x,MnO_x-CoO_x等活性组分,制备系列的催化剂用于低浓度氯苯的催化燃烧,研究催化剂的催化活性、选择性及稳定性.并利用XRD、N_2吸脱附、高分辨电镜-能谱分析、H_2-TPR和CB-TPD等手段对MCM-41及催化剂的织构-结构、表面形貌、活性组分分散状态、氧化还原性能及吸附性能等做了系统的研究.采用表面活性剂软模板技术合成了具有大比表面积、大孔径、耐热稳定性高的MCM-41介孔分子筛,负载不同比例的Mn/Co(摩尔比是3:1、6:1及9:1,其中总负载量为10%),以氯苯催化燃烧为探针反应,筛选出活性最佳时的Mn/Co比例.活性评价实验结果表明,各催化剂的活性以下列顺序依次降低:MnCo(6:1)/MCM-41>MnCo(9:1)/MCM-41>MnCo(3:1)/MCM-41>Mn/MCM-41>Co/MCM-41,其中MnCo(6:1)/MCM-41活性最佳,在270 oC即可完全催化燃烧氯苯.耐久性实验结果显示,MnCo(6:1)/MCM-41在连续反应1000 h后,其活性没有降低,表明其具有非常良好的稳定性.XRD实验结果表明,在Mn/MCM-41及Co/MCM-41催化剂上分别检测到MnO_2及Co_3O_4的特征衍射峰.在MnCo(6:1)/MCM-41催化剂上,MnO_2及Co_3O_4的特征衍射峰消失,同时出现了MnCoOx的特征衍射峰,这是由于MnO_2及Co_3O_4的强相互作用经过焙烧后形成的,且MnCoO_x的特征衍射峰较小,表明双金属活性组分的分散比单金属催化剂好.N_2吸脱附结果显示,MCM-41的比表面积达到805.9 m^2/g,孔体积达到0.795 cm^3/g.负载活性组分后其比表面积及孔体积均有不同程度的减小,这是由于活性组分进入了MCM-41的孔隙.高分辨电镜结果表明,MCM-41具有均匀的介孔孔道结构,MnCoO_x在MCM-41表面的颗粒小,分散好.能谱扫描出Mn,Co,O等元素,表明活性组分成功地负载在MCM-41载体上.H_2-TPR表明,双金属催化剂的还原峰温较单金属催化剂低,表明其具有更好的氧化性能.CB-TPD结果表明,MnCo双金属催化剂脱附氯苯的温度高于单金属催化剂,说明氯苯与催化剂之间的相互作用更强,即双金属催化剂对氯苯的吸附能力更强,使得氯苯催化燃烧更加充分,因此其催化性能更好.同时,深入探讨了MnO_x,CoO_x,MnCoO_x和MCM-41之间的相互作用及对催化燃烧性能的影响.

关键词： MCM-41分子筛 Mn/Co 催化燃烧氯苯表征

The Coix Genome Provides Insights into Panicoideae Evolution and Papery Hull Domestication

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Molecular Plant 2020年第2期13卷 309-320页

作者： Chao Guo Yanan Wang Aiguo Yang Jun He Chaowen Xiao Shanhua Lv Fengming Han Yibing Yuan Yuan Yuan Xiaolong Dong Juan Guo YawenYang-Hailan Liu Ningzhi zuo Yaxi Hu Kangxu Zhao Zhengbo Jiang Xing Wang Tingting Jiang Yaou Sherf Moju Cao Yuan Wang Zhaobo Long Tingzhao Rong Luqi Huang shufeng Zhou State Key Laboratory of Exploration and Utilization of Crop Gene Resources in Southwest China Key Laboratory of Biology and Genetic Improvement of Maize in Southwest RegionMinistry of AgricultureMaize Research Institute of Sichuan Agricultural UniversityChengdu 611130China National Resource Center for Chinese Materia Medica China Academy of Chinese Medical SciencesState Key Laboratory Breeding Base of Dao-di HerbsBeijing 100700China Tobacco Research Institute of Chinese Academy of Agricultural Sciences Qingdao 266101China Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengdu 610064China College of Agronomy Liaocheng UniversityLiaocheng 252000China Biomarker Technologies Corporation Beijing 101300China

Coix is a grass crop domesticated as early as the Neolithic era.It is still widely cultivated for both highly nutritional food and medicinal use.However,the genetic study and breeding of this crop are hindered by the lack of a sequenced genome.Here,we report de novo sequencing and assembly of the 1619-Mb genome of Coix,and annotation of 75.39%repeats and 39629 protein-coding genes.Comparative genomics analysis showed that Coix is more closely related to sorghum than maize,but intriguingly only Coix and maize had a recent genome duplication event,which was not detected in sorghum.We further constructed a genetic map and mapped several important traits,especially the strength of hull.Selection of papery hull(thin:easy dehulling)from the stony hull(thick:difficult dehulling)in wild progenitors was a key step in Coix domestication.The papery hull makes seed easier to process and germinate.Anatomic and global transcriptome analysis revealed that the papery hull is a result of inhibition of cell division and wall biogenesis.We also successfully demonstrated that seed hull pressure resistance is controlled by two major quantitative trait loci(QTLs),which are associated with hull thickness and color,respectively.The two QTLs were further fine mapped within intervals of 250 kb and 146 kb,respectively.These resources provide a platform for evolutionary studies and will facilitate molecular breeding of this important crop.

关键词： Coix genome Comparative genomics Panicoideae evolution hull domestication QTL mapping

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38CrMoAl圆钢调质裂纹形成原因分析

金属热处理 2023年第2期48卷 303-307页

作者：谭瑞松黄雁宋波左小坦朱利斌刘威杨树峰北京科技大学冶金与生态工程学院北京100083 芜湖新兴铸管有限责任公司安徽芜湖241002

国内某钢厂38CrMoAl钢在调质过程中出现了裂纹,对裂纹处进行取样,通过化学成分、宏观检测、显微组织分析、扫描电镜分析等探索裂纹产生的原因。结果表明,该钢裂纹性质为淬火裂纹,其产生的主要原因是原始材料圆坯存在冶金缺陷(缩松、点... 详细信息

国内某钢厂38CrMoAl钢在调质过程中出现了裂纹,对裂纹处进行取样,通过化学成分、宏观检测、显微组织分析、扫描电镜分析等探索裂纹产生的原因。结果表明,该钢裂纹性质为淬火裂纹,其产生的主要原因是原始材料圆坯存在冶金缺陷(缩松、点状偏析等),而调质过程中在组织应力和热应力作用下促进了裂纹的扩展。

关键词： 38CrMoAl圆钢淬火裂纹缺陷成分偏析