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Intermetallic PtBi core/ultrathin Pt shell nanoplates for efficient and I stable methanol and ethanol electro-oxidization
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作者 Xiaolei Yuan Xiaojing Jiang +7 位作者 Muhan Cao Lei Chen Kaiqi Nie Yong Zhang Yong Xu Xuhui Sun Yanguang Li Qiao Zhang 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第2期429-436,共8页
The development of Pt-based core/shell nanoparticles represents an emerging class of electrocatalysts for fuel cells, such as methanol oxidation reaction (MOR) and ethanol oxidation reaction (EOR). Here, we present a ... The development of Pt-based core/shell nanoparticles represents an emerging class of electrocatalysts for fuel cells, such as methanol oxidation reaction (MOR) and ethanol oxidation reaction (EOR). Here, we present a one-pot synthesis approach to prepare hexagonal PtBi/Pt core/shell nan ostructure composed of an in termetallic PtiBii core and an ultrathi n Pt shell with well-defined shape, size, and composition.The structure and the synergistic effect among different components enhanced their MOR and EOR performanee. The optimized Pt2Bi nanoplates exhibit excellent mass activities in both MOR (4,820 mA·mgpt^-1) and EOR (5,950 mA·mgpt^1) conducted in alkaline media, which are 6.15 times and 8.63 times higher than those of commercial Pt/C, respectively. Pt2Bi nan opiates also show superior operati on durability to commercial Pt/C. This work may inspire the rational design and synthesis of Pt-based nanoparticles with improved performance for fuel cells and other applications. 展开更多
关键词 intermetallics NANOPLATES core-shell structure METHANOL OXIDATION REACTION ETHANOL OXIDATION REACTION
Air-SAGD technology for super-heavy oil reservoirs 预览
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作者 GAO Yongrong GUO Erpeng +1 位作者 SHEN Dehuang WANG Bojun 《石油勘探与开发:英文版》 2019年第1期113-120,共8页
The air oxidation of super-heavy oil at low temperature was studied in laboratory and its influences on oil viscosity, component and steam sweep efficiency before and after air-injection were analyzed. The feasibility... The air oxidation of super-heavy oil at low temperature was studied in laboratory and its influences on oil viscosity, component and steam sweep efficiency before and after air-injection were analyzed. The feasibility, operation mode and air flooding effect at the late stage of steam assisted gravity drainage(SAGD) were investigated by numerical simulation. The experimental results show for vertical-horizontal well pair SAGD test area of Xing VI Formation in Block Du 84 of Liaohe Oilfield, the low temperature oxidation occurred between 150-250 ?C(steam chamber temperature), the oil viscosity increased greatly after low temperature oxidation, consequently, the oil displacement efficiency dropped sharply. Three development methods in the late stage of SAGD were simulated, i.e., steam + air low temperature oxidation, only air low temperature oxidation and only air high temperature oxidation. By comparing production dynamic curves and residual oil distribution etc., high temperature oxidation reduced the heat loss in late stage of SAGD, recovered the residual oil effectively, and prolonged reservoir development time. 展开更多
关键词 super HEAVY oil SAGD AIR injection low TEMPERATURE OXIDATION high TEMPERATURE OXIDATION
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高锰酸钾在咖啡因精制反应中的应用 预览
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作者 赵杰 赵旭 《化工设计通讯》 CAS 2019年第3期83-83,85共2页
概述了咖啡因的精制工艺。在其他工艺条件不变的基础上,通过调节高锰酸钾的加入量,提升合成咖啡因成品物料的质量。介绍了精制工艺在咖啡因工业化生产中的重要性及其应用前景。
关键词 咖啡因 精制 高锰酸钾 脱色 氧化
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HFO-1336mzz(Z)氧化分解机理的DFT研究
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作者 霍二光 刘朝 +1 位作者 徐肖肖 李期斌 《工程热物理学报》 EI CAS CSCD 北大核心 2019年第2期252-257,共6页
采用密度泛函理论(DFT)对HFO-1336mzz(Z)(CF3CH=CHCF3)的氧化分解机理进行研究,对可能的反应路径进行分析。结果表明:HFO-1336mzz(Z)氧化分解的起始反应可以分为两类,一类是工质自身的热分解,另一类是工质与氧气碰撞产生的分解。研究发... 采用密度泛函理论(DFT)对HFO-1336mzz(Z)(CF3CH=CHCF3)的氧化分解机理进行研究,对可能的反应路径进行分析。结果表明:HFO-1336mzz(Z)氧化分解的起始反应可以分为两类,一类是工质自身的热分解,另一类是工质与氧气碰撞产生的分解。研究发现工质与氧气碰撞发生的分解反应所需的活化能比工质自身的热分解要低,因此HFO-1336mzz(Z)更容易发生氧化分解。在随后的链式反应中,各反应路径的反应能垒普遍低于起始反应,说明自由基与工质分子的碰撞会加快工质的分解;并且大部分的链式反应是放热反应,可以为体系提供能量,促进反应的进行。本文从分子的角度对HFO-1336mzz(Z)的氧化分解机理进行了研究,为HFO类工质的氧化分解研究提供了参考。 展开更多
关键词 HFO-1336mzz(Z) 氧化 分解 密度泛函理论(DFT)
忍冬藤痛风颗粒联合非布司他片治疗痛风性关节炎临床研究 预览
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作者 艾力亚斯·阿不拉 赖敬波 《中国中医药信息杂志》 CAS CSCD 2019年第5期32-36,共5页
目的探讨忍冬藤痛风颗粒联合非布司他片治疗痛风性关节炎的临床疗效及其可能的作用机制。方法采用随机数字表法将144例痛风性关节炎患者分为对照组和研究组各72例。对照组予健康宣教,并予非布司他片,每次1~2片,每日1次,口服;研究组在对... 目的探讨忍冬藤痛风颗粒联合非布司他片治疗痛风性关节炎的临床疗效及其可能的作用机制。方法采用随机数字表法将144例痛风性关节炎患者分为对照组和研究组各72例。对照组予健康宣教,并予非布司他片,每次1~2片,每日1次,口服;研究组在对照组基础上予忍冬藤痛风颗粒,每日1剂,早晚2次冲服。2组均连续治疗24周。观察2组临床疗效,比较2组中医症状评分、血清尿酸、氧化应激指标[8-羟基脱氧鸟苷(8-OHdG)、3-硝基酪氨酸(3-NT)]及炎症因子[肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-1β、IL-6、C反应蛋白(CRP)]水平。结果研究组总有效率为91.67%(66/72),对照组为70.83%(51/72),研究组明显高于对照组(P<0.05)。与本组治疗前比较,2组治疗后中医症状评分及血清尿酸、8-OHdG、3-NT、TNF-α、IL-1β、IL-6、CRP水平明显下降(P<0.05);2组治疗后比较,研究组中医症状评分及血清尿酸、氧化应激指标、炎症因子水平明显低于对照组(P<0.05)。结论忍冬藤痛风颗粒联合非布司他片治疗痛风性关节炎患者临床疗效显著,可降低患者尿酸水平,抑制氧化应激反应和炎症反应。 展开更多
关键词 忍冬藤痛风颗粒 非布司他片 痛风性关节炎 氧化 炎症因子
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脉冲强光处理对菜籽油品质的影响 预览
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作者 周婷婷 曹少谦 +1 位作者 李丝丝 戚向阳 《中国粮油学报》 EI CAS CSCD 北大核心 2019年第1期57-62,113共7页
为探索脉冲强光(IPL)处理对富含油脂食品的影响,采用能量为500J的IPL对菜籽油进行照射,研究IPL处理对储藏过程中菜籽油氧化稳定性及相关成分的影响。结果表明,IPL处理可诱导菜籽油的氧化,增加总酚含量,降低α-生育酚含量,但其主要不饱... 为探索脉冲强光(IPL)处理对富含油脂食品的影响,采用能量为500J的IPL对菜籽油进行照射,研究IPL处理对储藏过程中菜籽油氧化稳定性及相关成分的影响。结果表明,IPL处理可诱导菜籽油的氧化,增加总酚含量,降低α-生育酚含量,但其主要不饱和脂肪酸含量变化不明显(P>0.05)。IPL处理组和对照组菜籽油储藏过程中的氧化程度均随时间的延长而增加,但处理组菜籽油过氧化值(POV)和p-茴香胺值(p-AV)的变化比对照组缓慢。储藏32d后,处理组菜籽油POV值、p-AV值和主要不饱和脂肪酸含量均显著低于对照组(P<0.05),而总酚含量仍显著高于对照组,α-生育酚含量则与对照组相比无显著差异。IPL处理能延缓储藏期内菜籽油的氧化及酚类物质含量的下降。本研究为IPL技术用于富脂食品的加工提供参考。 展开更多
关键词 脉冲强光(IPL) 菜籽油 氧化 主要成分
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高锰酸钾氧化对褐煤酸性基团的影响 预览
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作者 卢友志 王军正 黄润均 《化工技术与开发》 CAS 2019年第1期3-5,26共4页
探究了高锰酸钾溶液氧化褐煤时,时间、温度和氧化剂浓度对褐煤中的总酸值、羧基和羟基的影响。结果表明,当高锰酸钾溶液浓度为0.05mol·L^-1、反应温度为35℃、时间为30min时,余煤中总酸值、羟基和羧基的浓度分别是3.95mmol·g... 探究了高锰酸钾溶液氧化褐煤时,时间、温度和氧化剂浓度对褐煤中的总酸值、羧基和羟基的影响。结果表明,当高锰酸钾溶液浓度为0.05mol·L^-1、反应温度为35℃、时间为30min时,余煤中总酸值、羟基和羧基的浓度分别是3.95mmol·g^-1、3.85mmol·g^-1和0.1mmol·g^-1,相对原煤分别增加34%、增加48%和降低71.4%。红外光谱检测的结果表明,氧化没有破坏褐煤的主分子网络结构;分峰结果表明,氧化过程中缔合羟基的降解少,化合态羟基的降解多。 展开更多
关键词 褐煤 氧化 高锰酸钾
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Formation mechanism of yolk-shell LaMnO3 microspheres prepared by P123-template and oxidation of NO
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作者 Lihui WU Qiuling JIANG +2 位作者 Li WANG Ying WANG Mengxue WANG 《材料科学前沿:英文版》 SCIE CSCD 2019年第1期77-86,共10页
The yolk-shell LaMnO3 perovskite microspheres were fabricated by a novel,simple and mild soft template approach.A series of template-P123 concentrations(0-6.12 mmol·L^-1)were employed to optimize the most complet... The yolk-shell LaMnO3 perovskite microspheres were fabricated by a novel,simple and mild soft template approach.A series of template-P123 concentrations(0-6.12 mmol·L^-1)were employed to optimize the most complete spheres.When the concentration of P123 is 3.0 mmol·L^-1,the obtained yolk-shell microspheres with a diameter of 200-700 nm were constructed by nanoparticles.The possible formation mechanism of the yolk-shell microspheres was revealed step by step via XRD,SEM,TEM,EDS and HRTEM.Molecules of P123 were suitably mixed with solvents for double shelled vesicles through self-assembly,which interacted with metal complexes to form P123-metal vesicles.After the removal of P123 and citric acid by calcination at 700 ℃,the yolk-shell LaMnO3 microspheres with through-channels were obtained.Through-channels on the surface were due to citric acid and the solid core was attributed to the shrink of inner vesicles.Prepared yolk-shell microsphere samples possessed a larger surface area and a higher maximum NO conversion value of 78% at 314 ℃ for NO oxidation,compared with samples without the yolk-shell structure. 展开更多
关键词 perovskite yolk-shell MICROSPHERES NO OXIDATION
同轴连接器镀金层发黑的原因分析与对策 预览
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作者 樊磊 《电镀与涂饰》 CAS CSCD 北大核心 2019年第7期321-323,共3页
某镀金同轴连接器能够通过48h中性盐雾试验,但组装为连接线运输到日本客户处时却存在氧化发黑现象。分析认为是PVC(聚氯乙烯)材质的包装材料在运输过程中受热分解产生的HCl腐蚀了镀层。在PVC包装前增加PE(聚乙烯)材质的包装,该问题得到... 某镀金同轴连接器能够通过48h中性盐雾试验,但组装为连接线运输到日本客户处时却存在氧化发黑现象。分析认为是PVC(聚氯乙烯)材质的包装材料在运输过程中受热分解产生的HCl腐蚀了镀层。在PVC包装前增加PE(聚乙烯)材质的包装,该问题得到解决。 展开更多
关键词 连接器 镀金 包装 氧化 聚氯乙烯 热分解
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Influence of Cr3+ Concentration on SO2 Removal over TiO2 Based Multi-walled Carbon Nanotubes 预览
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作者 Yang Yanchun Jia Fengrui +3 位作者 Jian Weiwei Zhang Shaopeng Ma Danzhu Liu Guangxin 《中国炼油与石油化工:英文版》 SCIE CAS 2019年第1期23-35,共13页
In this study, titanium dioxide supported by multi-walled carbon nano tubes(MWCNTs/TiO2) and Cr-doped TiO2 supported by MWCNTs(MWNTs/Cr-TiO2) were synthesized by the sol-gel method. The prepared samples were character... In this study, titanium dioxide supported by multi-walled carbon nano tubes(MWCNTs/TiO2) and Cr-doped TiO2 supported by MWCNTs(MWNTs/Cr-TiO2) were synthesized by the sol-gel method. The prepared samples were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, the BrunauerEmmett-Teller analysis, and the Raman spectroscopy. The oxidation and efficiency for removal of SO2 in a simulated flue gas were investigated experimentally in a fixed-bed reactor. The 15% MWCNTs/Cr-Ti02 sample displayed excellent adsorption properties, and a SO2 removal rate equating to 30.415 1 mg/g from the simulated flue gas containing 2 300 μg/g of SO2, 8% of 02, and 5% of H20 was achieved under optimal conditions covering a temperature of 333.15 K, and a space velocity of 1 275 h^-1. The adsorption process was enhanced because Cr doping modified the pore structure and inhibited the grain growth of TiO2. In addition, the Freundlich and Langmuir models revealed that SO2 was mainly adsorbed through chemical adsorption on the sample surfaces, and the thermodynamic model analysis indicated that the adsorption was a spontaneous, exothermic, and entropy-reducing process. The adsorption kinetics of SO2 can be described by the pseudosecond-order kinetic and the Bangham dynamics models. The possible reaction mechanism involved in desulfurization process was also proposed. 展开更多
关键词 MWCNTs/ TIO2 Cr DOPING SO2 removal OXIDATION
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Ag-Sn-In合金粉末高压氧化机制的研究
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作者 徐晓燕 李波 +3 位作者 黄锡文 刘心宇 袁昌来 黄兴隆 《稀有金属》 EI CAS CSCD 北大核心 2019年第1期102-107,共6页
采用雾化法制备了Ag-8 Sn-3.7 In(%,质量分数)合金粉末。分别研究了氧气压力、氧化温度及氧化时间对Ag-8 Sn-3.7 In合金粉末氧化行为的影响规律。系统地分析了Ag-8 Sn-3.7 In合金粉末氧化前后的物相组成、粉末粒度、表面形貌及表面成分... 采用雾化法制备了Ag-8 Sn-3.7 In(%,质量分数)合金粉末。分别研究了氧气压力、氧化温度及氧化时间对Ag-8 Sn-3.7 In合金粉末氧化行为的影响规律。系统地分析了Ag-8 Sn-3.7 In合金粉末氧化前后的物相组成、粉末粒度、表面形貌及表面成分。研究结果表明:Ag·SnO2·In2O3合金粉末高压氧化条件中,温度起决定性的作用,选择合适的氧化温度是该氧化工艺的关键。当温度不够高时,需要长时间才能达到完全氧化。氧气压力可以加快氧化的进程,当氧气压力达到0.75 MPa以后,增大氧气压力,意义不大。对三种不同氧化工艺得到的Ag·SnO2·In2O3合金粉末进行成分分析,在氧化完全的条件下,氧化温度越高,其表面偏析现象越低。在Ag-Sn-In合金粉末高压氧化过程中,氧向合金粉末内部扩散, Sn和In向粉末表面扩散,与O2反应分别形成SnO2和In2O3,聚集在颗粒表面的SnO2相和In2O3相在表面反应,形成表面2In2O3·3SnO2壳层,阻碍了Sn原子的进一步扩散。对于Ag-8 Sn-3.7 In(%,质量分数)合金粉末,较好的氧化参数为:氧化温度500℃,氧气压力0.75 MPa,氧化时间2 h。 展开更多
关键词 Ag-Sn-In合金粉末 氧化 偏析
A Simple Strategy for Fabrication of In(OH)3/ZnIn2S4 Heterostructure as Visible-light-driven Photocatalyst for Selective Oxidation 预览
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作者 陈志鑫 《结构化学》 SCIE CAS CSCD 2019年第5期825-836,672共13页
The cubic In(OH)3/ZnIn2S4 heterostructures were successfully synthesized via a simple strategy of post-treatment of cubic ZnIn2S4(C-ZIS), and their structures and properties were characterized by X-ray diffraction(XRD... The cubic In(OH)3/ZnIn2S4 heterostructures were successfully synthesized via a simple strategy of post-treatment of cubic ZnIn2S4(C-ZIS), and their structures and properties were characterized by X-ray diffraction(XRD), UV-vis diffuse reflectance spectra(DRS), field emission scanning electron microscopy(FESEM) and transmission electron microscopy(TEM). According to the results, the tofu-like In(OH)3 semiconductor as a new crystal phase appeared in the matrix of C-ZIS and formed a In(OH)3/ZnIn2S4 heterostructure. Compared with pure C-ZIS, the heterostructure exhibits higher photocatalytic activity towards selective oxidation of benzyl alcohol under visible light. The In(OH)3/ZnIn2S4 heterostructure manifests the best and the highest photocatalytic performance via 18 h post-treatment, which achieved nearly 100% selectivity, 35.5%conversion and 34.5% yield. This is ascribed to the formation of In(OH)3/ZnIn2S4 heterostructure to promote the transfer of photogenerated electron-hole pairs and thus efficiently inhibits their recombination, leading to the longer lifetime of photo-induced carriers. Furthermore, a possible photocatalytic mechanism is proposed and discussed. Our current work could boost more interest in researching the semiconductor materials of ternary chalcogenides and enlarging the applications based on cubic ZnIn2S4 heterostructure as visible-light-driven photocatalyst. 展开更多
关键词 ZnIn2S4 In(OH)3 HETEROSTRUCTURE POST-TREATMENT SELECTIVE OXIDATION
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Reduced graphene oxide supported Pd-Cu-Co trimetallic catalyst:synthesis,characterization and methanol electrooxidation properties 预览
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作者 Fan Yang Bing Zhang +4 位作者 Sen Dong Chunxia Wang Andong Feng Xiaoxu Fan Yongfeng Li 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第2期72-78,共7页
Trimetallic palladium-copper-cobalt nanoparticles supported on reduced graphene oxide(PdCuCo/RGO)with different molar ratios of Pd,Cu and Co can be synthesized by facile chemical reduction with NaBH4 as reductant and ... Trimetallic palladium-copper-cobalt nanoparticles supported on reduced graphene oxide(PdCuCo/RGO)with different molar ratios of Pd,Cu and Co can be synthesized by facile chemical reduction with NaBH4 as reductant and cetrimonium bromide as stabilizer.The morphology,structure and composition of the as-synthesized catalysts are characterized by transmission electron microscopy,X-ray diffraction and Xray photoelectron spectroscopy.The cyclic voltammetry and chronoamperometry are utilized to investigate the electrochemical activities and stabilities of the as-obtained catalysts.The results demonstrate that the PdCuCo/RGO catalyst shows superior catalytic activity and stability for methanol electrooxidation in alkaline media compared with PdCu/RGO,PdCo/RGO,and Pd/RGO catalysts.These findings suggest that the PdCuCo/RGO catalyst possesses a great potential as a promising anode catalyst for direct methanol fuel cells. 展开更多
关键词 Trimetallic NANOPARTICLES REDUCED graphene OXIDE METHANOL OXIDATION
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Modification of NiCoCrAlY with Pt: Part Ⅰ. Effect of Pt depositing location and cyclic oxidation performance
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作者 Yingfei Yang Hongrui Yao +2 位作者 Zebin Bao Pan Ren Wei Li 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第3期341-349,共9页
Pt layers of 5 μm in thickness were electroplated before or after depositing NiCoCrAlY coating by arc ion plating(AIP) aiming for identifying the effect of Pt enriching position on microstructure and cyclic oxidation... Pt layers of 5 μm in thickness were electroplated before or after depositing NiCoCrAlY coating by arc ion plating(AIP) aiming for identifying the effect of Pt enriching position on microstructure and cyclic oxidation behavior of Pt modified NiCoCrAlY coatings. Al-rich zones formed at the same position of Ptrich zones for both modified coatings due to uphill diffusion of Al driven by Pt. Cyclic oxidation tests at 1000 and 1100?C indicated that oxidation resistance of NiCoCrAlY was improved by Pt modification via different mechanisms: at surface, Pt-rich zone promoted selective oxidation of Al to form α-Al2O3,whilst at coating/substrate interface Pt-rich zone acted as effective diffusion barrier for titanium. Roles of Pt played in enhancing the oxidation performance of various Pt-modified NiCoCrAlY coating were investigated. 展开更多
关键词 CYCLIC oxidation Pt-modification NICOCRALY Electron PROBE micro-analysis(EPMA)
木素氧化降解的研究进展
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作者 李梦晓 周学飞 《纸和造纸》 2019年第2期15-20,共6页
木素是一种天然聚合物,在自然界中的储量排第二,但是在生物质精炼过程中其用途和定向功能化仍然需要进一步探索和发展。木素的氧化降解具有很好的发展前景,可以用来生产高度功能化的单体或者低聚物作为化学或制药行业其他精细化学品的... 木素是一种天然聚合物,在自然界中的储量排第二,但是在生物质精炼过程中其用途和定向功能化仍然需要进一步探索和发展。木素的氧化降解具有很好的发展前景,可以用来生产高度功能化的单体或者低聚物作为化学或制药行业其他精细化学品的原材料。本文根据木素的结构特征、分离及表征方法和氧化领域的一些重要成果,综述了有机金属催化(MTO、金属卟啉、salen复合物、POMs)和酶催化(漆酶、过氧化物酶)对木素以及木素模型物的氧化作用、反应机制的影响和反应结果的处理方法。 展开更多
关键词 木素 氧化 降解 催化
Influence of solution treatment on microstructure, corrosion resistance, and oxidation behavior of cast G-NiCr28W alloy
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作者 Alptekin Kisasoz 《中国铸造:英文版》 SCIE 2019年第1期63-70,共8页
G-NiCr28W is a nickel-based cast alloy. Its microstructure consists of nickel-rich matrix phase and chromium-rich eutectic carbides. The solution treatment process can provide homogenous microstructure and desired mec... G-NiCr28W is a nickel-based cast alloy. Its microstructure consists of nickel-rich matrix phase and chromium-rich eutectic carbides. The solution treatment process can provide homogenous microstructure and desired mechanical/thermal properties for G-NiCr28W alloy. However, the solution treatment process affects the corrosion resistance of the alloy and it causes metal loss due to the occurrence of oxidation at atmospheric conditions. Therefore, determining the changes in the properties of the G-NiCr28W is important. For this purpose, G-NiCr28W specimens were solution treated at 1,040 ℃, 1,100 ℃ and 1,160 ℃ for 1 h and 8 h, respectively. The microstructures of the solution-treated samples were characterized by optical microscopy, scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction analysis. Moreover, hardness, corrosion resistance and oxidation behaviors of the solution-treated samples were examined. The solution treatment process applied at 1,160 ℃ led to the formation of Fe2W2C blocky carbides, and hardness of the sample increased with the existence of blocky carbides, while corrosion resistance decreased. Furthermore, excessive metal loss occurred depending on oxidation due to the high process temperature at 1,160 ℃. 展开更多
关键词 G-NiCr28W nickel-based ALLOY heat treatment corrosion behaviour OXIDATION
光照强度对大豆调和油氧化的影响
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作者 刘志明 唐彦君 +3 位作者 孙清瑞 时宁宁 张亚瑾 陈洵 《食品科技》 CAS 北大核心 2019年第4期190-194,共5页
试验研究照度(I)对大豆调和油(BSO)氧化的影响规律。在50℃、大气氧分压(21.0 kPa)、实验室相对湿度40%和50%初始顶空率的固定条件下,分别控制I为0、400、800、1600、3200lx,测定不同氧化时间(t)时BSO的过氧化值(POV),绘制POV﹣t曲线,... 试验研究照度(I)对大豆调和油(BSO)氧化的影响规律。在50℃、大气氧分压(21.0 kPa)、实验室相对湿度40%和50%初始顶空率的固定条件下,分别控制I为0、400、800、1600、3200lx,测定不同氧化时间(t)时BSO的过氧化值(POV),绘制POV﹣t曲线,进行数学回归,计算反应速率常数(k)。结果表明,BSO的氧化符合零级反应动力学特征,k为0.84×10-2~3.48×10-2 mol/kg·h。I相同时,POV随t的延长而线性增大;t相同时,POV随I的增大而升高。k与I的关系符合二项式k=-3×10-9I2+2×10-5I+0.0076。试验揭示,以POV为表征参数,能够定量反映BSO氧化的动力学规律,避光贮存有利于降低BSO的氧化速率。 展开更多
关键词 大豆调和油 光照强度 氧化 过氧化值 速率常数
添加迷迭香提取物对油茶籽油储藏稳定性的影响 预览
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作者 刘耀华 宋永 齐宝坤 《中国调味品》 CAS 北大核心 2019年第1期32-35,共4页
以添加迷迭香提取物的油茶籽油为研究对象,通过Schaal烘箱法在(62±1)℃条件下,储藏0,6,12,18,24天。通过测定样品的过氧化值、酸价、p-茴香胺值、全过氧化值。比较样品的储藏稳定性。结果表明:随着加热时间的延长,油茶籽油的过氧... 以添加迷迭香提取物的油茶籽油为研究对象,通过Schaal烘箱法在(62±1)℃条件下,储藏0,6,12,18,24天。通过测定样品的过氧化值、酸价、p-茴香胺值、全过氧化值。比较样品的储藏稳定性。结果表明:随着加热时间的延长,油茶籽油的过氧化值、酸价和全过氧化值呈现增大的趋势,p-茴香胺值快速增加;添加迷迭香提取物的油茶籽油在加热过程中表现出较低的过氧化值、酸价、p-茴香胺值和全过氧化值改变,说明迷迭香提取物具有较高的抗氧化性,在抑制油脂氧化方面有着明显的作用。 展开更多
关键词 迷迭香提取物 油茶籽油 储藏稳定性 氧化
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TiO2/Schwertmannite nanocomposites as superior co-catalysts in heterogeneous photo-Fenton process
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作者 Yanping Zhu Chun Zeng +5 位作者 Runliang Zhu Yin Xu Xingyan Wang Huijun Zhou Jianxi Zhu Hongping He 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第6期208-217,共10页
The heterogeneous photo-Fenton reaction is an effective technique in combating organic contaminants for both soil and water remediation,and extensive studies have focused on enhancing its efficiency and reducing its c... The heterogeneous photo-Fenton reaction is an effective technique in combating organic contaminants for both soil and water remediation,and extensive studies have focused on enhancing its efficiency and reducing its costs.In this work,we developed novel photoFenton catalysts by simply milling commercially available TiO2(P25)with Schwertmannite(Sh),a natural iron-oxyhydroxysulfate nanomineral.We expect that the photo-generated electrons from TiO2could continuously migrate to Sh,which then could enhance the separation of electron-hole pairs on TiO2and accelerate the reduction of Fe(III)to Fe(II)on Sh,leading to high degradation efficiency of the target organic contaminants.SEM and TEM results showed the distribution of TiO2on Sh surface for the nanocomposites(TiO2/Sh).Under simulated sunlight irradiation,the much higher content of Fe(II)was determined on TiO2/Sh than on Sh via a common method in the iron ore,and the consumption of H2O2and the production of·OH were more significant in the TiO2/Sh system than those in the TiO2and Sh systems.These results well support our hypothesis that the photo-generated electrons could migrate from TiO2to Sh on the composites,and can also explain the much higher degradation efficiency of Rhodamine B(RhB)in the TiO2/Sh system.Besides,TiO2/Sh had lower Fe dissolution as compared with Sh,and retained high catalytic stability after four repeated cycles.Above merits of the TiO2/Sh composites,in combining with their simple synthesis method and low-cost property,indicated that they should have promising applications as heterogeneous photo-Fenton catalysts. 展开更多
关键词 PHOTO-FENTON reaction Semiconductor SCHWERTMANNITE Advanced oxidation
Effect of Al Layer on Oxidation Behavior of NbCrAl Coating
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作者 XU An CHEN Quanzhi +2 位作者 HUANG Zujiang DONG Wanbing LI Weizhou 《武汉理工大学学报:材料科学英文版》 SCIE EI CAS 2019年第2期391-396,共6页
NbCrAl coatings in the presence or absence of Al outer layer were prepared on C103 Nb based alloy and alumina substrate by direct current magnetron sputtering technique. The oxidation performance of coating systems wa... NbCrAl coatings in the presence or absence of Al outer layer were prepared on C103 Nb based alloy and alumina substrate by direct current magnetron sputtering technique. The oxidation performance of coating systems was evaluated by isothermal oxidation tests. The element diffusion and oxidation behavior of the coating systems were investigated. The results indicate that the mass gains of NbCrAl and Al/NbCrAl coatings are 2.02 mg/cm2 and 0.79 mg/cm2 at 1 000 ℃ for short time. Al/NbCrAl coatings exhibit more effective protection than NbCrAl coatings. The addition of Al layer can improve the oxidation resistance of NbCrAl coatings, which is attributed to the Al layer offering enough Al content to react with oxygen to form a continuous and dense Al2O3 scale on NbCrAl coating and it can inhibit the further internal oxidation. 展开更多
关键词 NbCrAl COATING element DIFFUSION OXIDATION behavior direct current MAGNETRON SPUTTERING
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