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氧化磷化工艺技术研究 被引量:1
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作者 王辉 杜兴胜 王荣 《中国新技术新产品》 2013年第4期28-28,共1页
本文通过试验确定了氧化磷化工艺参数,对氧化磷化后进行憎水处理的试样进行了耐蚀性测试,其耐蚀性达到22小时无锈蚀,满足了设计要求。
关键词 氧化磷化 憎水处理 耐蚀性 工艺
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混晶型磷化膜的制备及其耐蚀性能 被引量:3
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作者 张丕俭 胡玉才 +1 位作者 殷平 刘冰 《材料保护》 CAS CSCD 北大核心 2008年第12期57-58,64,共3页
为改进常规晶型和非晶型磷化膜性能的不足,以常温磷化液为基础,通过改变磷化操作工艺,利用波段操作将浸泡磷化与空气中氧化磷化相结合,将晶型磷化膜与非晶型磷化膜有机地结合为一体,制备了混晶型磷化膜,并用硫酸铜点滴试验检测了磷化膜... 为改进常规晶型和非晶型磷化膜性能的不足,以常温磷化液为基础,通过改变磷化操作工艺,利用波段操作将浸泡磷化与空气中氧化磷化相结合,将晶型磷化膜与非晶型磷化膜有机地结合为一体,制备了混晶型磷化膜,并用硫酸铜点滴试验检测了磷化膜的耐蚀性能。结果表明,混晶型磷化膜硫酸铜点滴变色时间延长了1倍左右,大大提高了磷化膜的耐蚀性能。 展开更多
关键词 常温磷 混晶型磷 氧化磷化 耐蚀性能
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新型磷化工艺的研究 被引量:2
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作者 李博 胡建雄 《电镀与环保》 CAS CSCD 北大核心 2019年第2期43-46,共4页
介绍了YBφ磷化液配方及工艺流程,总结了YBφ磷化液的配制和维护经验,并对三种磷化工艺进行了对比分析。结果表明:YBφ磷化膜为微孔结构,与基体结合牢固,与漆层结合良好,耐蚀性与HB/Z 5080磷化膜的相当,氢脆性合格。YBφ磷化膜能够完全... 介绍了YBφ磷化液配方及工艺流程,总结了YBφ磷化液的配制和维护经验,并对三种磷化工艺进行了对比分析。结果表明:YBφ磷化膜为微孔结构,与基体结合牢固,与漆层结合良好,耐蚀性与HB/Z 5080磷化膜的相当,氢脆性合格。YBφ磷化膜能够完全替代HB/Z 5080磷化膜、氧化磷化膜,用于起落架碳钢和低合金钢零件的表面防护。 展开更多
关键词 YBφ磷 HB/Z5080磷 氧化磷化 耐蚀性
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Ultra-deep oxidative desulfurization of fuel with H_2O_2 catalyzed by phosphomolybdic acid supported on silica 被引量:8
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作者 田永胜 王光辉 +3 位作者 龙娟 崔佳伟 金伟 曾丹林 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第12期2098-2105,共8页
A highly active catalyst of phosphomolybdic acid ~HPMo) was prepared and applied in the catalytic oxidative desulfurization (CODS) system. The catalyst was characterized by FT-IR, XRD, XPS and superconducting NMR. ... A highly active catalyst of phosphomolybdic acid ~HPMo) was prepared and applied in the catalytic oxidative desulfurization (CODS) system. The catalyst was characterized by FT-IR, XRD, XPS and superconducting NMR. The influences of rn(catalyst)/m(oil), V(H202)fV(oil), reaction temperature and reaction time on the fractional conversion of benzothiophene (BT) and dibenzothiophene (DBT) were investigated. GC-MS and micra-coulometric methods were employed to investigate the reaction. The catalyst has high desulfurization activity in the removal of BT and DBT under mild conditions. The recycling experiments indicated that DBT and BT removal could still reach 95.2% and 95.7% after 10 cycles. 展开更多
关键词 Mesoporous silica Phosphomolybdic acid Oxidative desulfurization Benzothiophene Dibenzothiophene
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Analysis on Activity of Immunity-related Enzymes in First Familiar Generation and Self Cross F1 of Platichthys stellatus Pallas 被引量:4
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作者 郑明刚 仝颜丽 +4 位作者 王玲 焉翠蔚 刘峰 王波 刘振华 《Agricultural Science & Technology》 CAS 2010年第7期168-170,共3页
[Objective] The aim was to study the activity of immunity-related enzymes in each tissue of self cross F1 of Platichthys stellatus Pallas and first familiar generation of P.stellatus ♀×Verasper variegates ♂.[Me... [Objective] The aim was to study the activity of immunity-related enzymes in each tissue of self cross F1 of Platichthys stellatus Pallas and first familiar generation of P.stellatus ♀×Verasper variegates ♂.[Method] The activity difference of three important non-specific immunity-related enzymes:acid phosphatase (ACP),alkaline phosphatase (AKP) and superoxide dismutase (SOD) existed in muscle,liver,spleen and intestine of first familiar generation and self cross F1 of P.stellatus was compared.[Result] The activity of ACP and AKP in muscle,liver and intestine of first familiar generation was higher than that of self cross F1,while the activity of ACP and AKP in liver of first familiar generation showed no significant difference with that of self cross F1; the SOD activity decreased significantly in tissues expected for muscle.[Conclusion] The result had provided theoretic basis for the breeding of P.stellatus. 展开更多
关键词 Platichthys stellatus Acid phosphatase (ACP) Alkaline phosphatase (AKP) Superoxide dismutase (SOD)
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AF1410超高强度钢表面防护工艺研究 被引量:2
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作者 李江 李博 +1 位作者 焦遥 朱鹏程 《新技术新工艺》 2020年第8期23-26,共4页
针对国内少见有对16Co14Ni10Cr2Mo(AF1410)超高强度钢表面防护的公开报道,为满足其表面防护需求,采用以23Co14Ni12Cr3MoE(A-100)钢为基础做对比的试验方法,研究了AF1410钢镀硬铬、镀镉-钛、氧化磷化及涂漆等主要防护工艺。结果表明,AF1... 针对国内少见有对16Co14Ni10Cr2Mo(AF1410)超高强度钢表面防护的公开报道,为满足其表面防护需求,采用以23Co14Ni12Cr3MoE(A-100)钢为基础做对比的试验方法,研究了AF1410钢镀硬铬、镀镉-钛、氧化磷化及涂漆等主要防护工艺。结果表明,AF1410钢镀硬铬较困难,所需电流密度为A-100钢的4~6倍;镀镉-钛、氧化磷化和涂漆等与A-100钢没有明显差别。 展开更多
关键词 AF1410钢 A-100钢 镀铬 镀镉-钛 氧化磷化 涂漆 表面防护
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Promotional effect of H_3PO_4 on ceria catalyst for selective catalytic reduction of NO by NH_3 被引量:5
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作者 易婷 张一波 +1 位作者 李经纬 杨向光 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第2期300-307,共8页
A series of H3PO4-modified CeO2 samples were prepared by impregnation of CeO2 with H3PO4solution,and evaluated for the selective catalytic reduction of NOx by NH3.The samples were characterized by X-ray diffraction,N2... A series of H3PO4-modified CeO2 samples were prepared by impregnation of CeO2 with H3PO4solution,and evaluated for the selective catalytic reduction of NOx by NH3.The samples were characterized by X-ray diffraction,N2 adsorption-desorption,infrared spectroscopy,Raman spectroscopy,X-ray photoelectron spectroscopy,temperature-programmed desorption of NH3,and temperature-programmed reduction of H2.The results showed that more than 80%NO conversion was achieved in the temperature range 250-550℃ over the H3PO4-CeO2 catalyst.The enhanced catalytic performance could be ascribed to the increase in acidic strength,especially Bronsted acidity,and reduction in redox properties of the CeO2 after H3PO4 modification. 展开更多
关键词 AMMONIA Selective catalytic reduction CERIA Phosphoric acid Redox ACIDITY
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Implications of mitochondrial DNA mutations and mitochondrial dysfunction in tumorigenesis 被引量:20
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作者 Jianxin Lu Lokendra Kumar Sharma Yidong Bai 《Cell Research》 SCIE CAS CSCD 2009年第7期802-815,共14页
Alterations in oxidative phosphorylation resulting from mitochondriai dysfunction have long been hypothesized to be involved in tumorigenesis. Mitochondria have recently been shown to play an important role in regulat... Alterations in oxidative phosphorylation resulting from mitochondriai dysfunction have long been hypothesized to be involved in tumorigenesis. Mitochondria have recently been shown to play an important role in regulating both programmed cell death and cell proliferation. Furthermore, mitochondrial DNA (mtDNA) mutations have been found in various cancer cells. However, the role of these mtDNA mutations in tumorigenesis remains largely unknown. This review focuses on basic mitochondrial genetics, mtDNA mutations and consequential mitochondrial dysfunction associated with cancer. The potential molecular mechanisms, mediating the pathogenesis from mtDNA mutations and mitochondrial dysfunction to tumorigenesis are also discussed. 展开更多
关键词 mitochondrial DNA mutation CANCER ROS APOPTOSIS
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Nitric oxide: orchestrating hypoxia regulation through mitochondrial respiration and the endoplasmic reticulum stress response 被引量:7
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作者 Ian G. CHARLES Salvador MONCADA 《Cell Research》 SCIE CAS CSCD 2005年第1期63-65,共3页
Mitochondria have long been considered to be the powerhouse of the living cell, generating energy in the form of the molecule ATP via the process of oxidative phosphorylation. In the past 20 years, it has been recogni... Mitochondria have long been considered to be the powerhouse of the living cell, generating energy in the form of the molecule ATP via the process of oxidative phosphorylation. In the past 20 years, it has been recognised that they also play an important role in the implementation of apoptosis, or programmed cell death. More recently it has become evident that mitochondria also participate in the orchestration of cellular defence responses.At physiological concentrations, the gaseous molecule nitric oxide (NO) inhibits the mitochondrial enzyme cytochrome c oxidase (complex IV) in competition with oxygen. This interaction underlies the mitochondrial actions of NO, which range from the physiologi- cal regulation of cell respiration, through mitochondrial signalling, to the development of “metabolic hypoxia” – a situation in which, although oxygen is available, the cell is unable to utilise it. 展开更多
关键词 nitric oxide HYPOXIA MITOCHONDRIA endoplasmic reticulum stress.
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Mass Spectrometric Studies of Selective Oxidation of n-Butane over a Vanadium Phosphorus Oxide Catalyst 被引量:2
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作者 陈标华 黄晓峰 +2 位作者 李成岳 梁日忠 赵邦蓉 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第2期177-182,共6页
The selective oxidation of n-butane to maleic anhydride (MA) on a vanadium-phosphorus oxide (VPO) catalyst was studied using on-line gas-chromatography combined with mass spectrometry(GC-MS) and transient response tec... The selective oxidation of n-butane to maleic anhydride (MA) on a vanadium-phosphorus oxide (VPO) catalyst was studied using on-line gas-chromatography combined with mass spectrometry(GC-MS) and transient response technique. The reaction intermediates, buterie and furan, were found in the reaction effluent under near industrial feed condition (3% butane+15%O2), while dihydrofuran was detected at high butane concentration (12% butane, 5%O2). Some intermediates of MA decomposition were also identified. Detection of these intermediates shows that the vanadium phosphorus oxides are able to dehydrogenate butane to butene, and butene further to form MA. Based on these observations, a modified scheme of reaction network is proposed. The transient experiments show that butane in the gas phase may directly react with oxygen both on the surface and from the metal oxide lattice, without a proceeding adsorption step. Gas phase oxygen can be adsorbed and transformed to surface lattice oxygen but it can not participate in selective oxidation. Adsorbed oxygen leads to deep oxidation, while lattice oxygen leads to selective oxidation. 展开更多
关键词 n-butane selective oxidation vanadium phosphorus oxide catalyst mass spectrometer reaction in- termediates transient response
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Killing Effect of Mixed Fumigation of Phosphine and Carbon Dioxide on Eggs of Lasioderma serricorne F. 被引量:2
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作者 彭涛 刘师伟 +2 位作者 谭琳 余兴江 郭年梅 《Agricultural Science & Technology》 CAS 2015年第12期2730-2732,共3页
[Objective] This study aimed to investigate the killing effect of mixed fumi- gation of phosphine and carbon dioxide on eggs of Lasioderma serricorne F. [Method] The outside-storage phosphine generator was placed in a... [Objective] This study aimed to investigate the killing effect of mixed fumi- gation of phosphine and carbon dioxide on eggs of Lasioderma serricorne F. [Method] The outside-storage phosphine generator was placed in a tabernacled smoke box, and the mortality rates of L. serricome F. eggs in the smoke box under conditions of different aluminium phosphide usage amount and different fumigation time were studied. In addition, the times needed by tabernacle and smoke box cen- ter to reach the phosphine concentration peak were recorded. [Result] The optimum conditions for killing the eggs of L. serricorne were as follows: temperature of (27± 2) ℃, relatively humidity of (45±5)%, aluminium phosphide usage amount of 1.5 g/m3 and effective exposure time of 96 h. The killing effect of mixed fumigation of phos- phine and carbon dioxide was increased with the extension of fumigation time. The increased usage amount of aluminium phosphide showed no significant effect on killing effect. The tabernacle space and smoke box center all required relatively short time to reach the phosphine concentration peak. If the tabernacle had a good airtightness, the overall fumigation time could be shortened. [Conclusion] The fumi- gation method is reliable, and it can be used for the control of L. serricorne F. in tobacco storage. 展开更多
关键词 Mixed fumigation of phosphine and carbon dioxide Lasioderma serri- come F. Egg Fumigation time Mortality rate
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CoNiP/NC polyhedrons derived from cobalt-based zeolitic imidazolate frameworks as an active electrocatalyst for oxygen evolution 被引量:2
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作者 Jintang Li Guiqing Du +2 位作者 Xian Cheng Pingjing Feng Xuetao Luo 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第5期982-987,共6页
The oxygen evolution reaction(OER)plays an important role in the development of energy conversation and storage technologies including water splitting and metal-air batteries,where the development of electrocatalysts ... The oxygen evolution reaction(OER)plays an important role in the development of energy conversation and storage technologies including water splitting and metal-air batteries,where the development of electrocatalysts is paramount.In this study,cobalt-nickel phosphide/N-doped porous carbon polyhedron electrocatalysts(CoNiP/NC)were prepared by a facile two-step carbonization method and subsequent phosphorization calcination in an Ar atmosphere using cobalt-based zeolitic imidazolate frameworks(ZIFs)as precursors.Among the electrocatalysts obtained by controlling the carbonization and phosphorization temperature,the CoNiP/NC700 catalyst,where 700 refers to the calcination temperature(°C),exhibited superior electrocatalytic activity for the OER with an onset overpotential of approximate 220 mV and an overpotential of approximate 300 mV in alkaline solution at a current density of 10 mA/cm2.The CoNi/NC and Co/NC Samples were also tested for comparison and CoNiP/NC exhibited the better electrocatalytic activity at all the temperatures tested.The superior electrocatalytic activity of the phosphorization hybrid material can be attributed to the superior synergistic effect of Co,Ni,P and C due to their strong electron coupling interactions.The interconnected amorphous carbon anchored the active Co compounds to avoid aggregation and maintained conducting channels for electron transfer.The composite electrocatalyst prepared herein is a promising candidate for use in electrocatalytic OERs. 展开更多
关键词 ZIF-67 CARBONIZATION Phosphorization ELECTROCATALYST Oxygen evolution reaction
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Elevated nitric oxide and 3',5' cyclic guanosine monophosphate levels in patients with alcoholic cirrhosis 被引量:1
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作者 Cíntia Siqueira Miguel Carneiro de Moura +1 位作者 Ana Júlia Pedro Paula Rocha 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第2期236-242,共7页
AIM: To evaluate whether serum levels of nitric oxide (NO ·) and plasma levels of cyclic guanosine monophosphate (cGMP) and total glutathione (GSH) are altered in patients with alcoholic cirrhosis and to examine ... AIM: To evaluate whether serum levels of nitric oxide (NO ·) and plasma levels of cyclic guanosine monophosphate (cGMP) and total glutathione (GSH) are altered in patients with alcoholic cirrhosis and to examine their correlation with the severity of liver disease.METHODS: Twenty-six patients with alcoholic liver cirrhosis were studied. Serum levels of NO · and plasma levels of cGMP and GSH were measured in 7 patients with compensated alcoholic cirrhosis (Child-Pugh A) and 19 patients with advanced cirrhosis (Child-Pugh B and C). The model for end-stage liver disease (MELD) score was evaluated. Sixteen healthy volunteers served as controls. Liver enzymes and creatinine levels were also tested.RESULTS: NO · and cGMP levels were higher in patients with Child-Pugh B and C cirrhosis than in Child-Pugh A cirrhosis or controls (NO ·: 21.70 ± 8.07 vs 11.70 ± 2.74; 21.70 ± 8.07 vs 7.26 ± 2.47 μmol/L, respectively; P < 0.001) and (cGMP: 20.12 ± 6.62 vs 10.14 ± 2.78; 20.12 ± 6.62 vs 4.95 ± 1.21 pmol/L, respectively; P < 0.001). Total glutathione levels were lower in patients with Child-Pugh B and C cirrhosis than in patients with Child-Pugh A cirrhosis or controls (16.04 ± 6.06 vs 23.01 ± 4.38 or 16.04 ± 6.06 vs 66.57 ± 26.23 μmol/L, respectively; P < 0.001). There was a significant correlation between NO · and cGMP levels in all patients with alcoholic cirrhosis. A significant negative correlation between reduced glutathione/glutathione disulfide and the MELD score was found in all cirrhotic patients.CONCLUSION: Our results suggest a role for oxidative stress in alcoholic liver cirrhosis, which is more significant in decompensated patients with higher levels of NO ·and cGMP and lower GSH levels than in compensated and control patients. Altered mediator levels in decompensated patients may influence the hemodynamic changes in and progression of liver disease. 展开更多
关键词 Oxidative stress Nitric oxide Alcoholic cirrhosis FIBROSIS Model for end-stage liver disease
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6 Kinds of Isozymes after Long-term Subculture of Emmenopterys henryi Oliv. 被引量:5
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作者 杜景川 景丹龙 +1 位作者 陈发菊 李凤兰 《Agricultural Science & Technology》 CAS 2010年第5期22-27,共6页
[Objective] The aim was to study the changes of zymography in 6 kinds of isozymes after long-term subculture of Emmenopterys henryi Oliv.. [Method] Non-denaturing polyacrylamide gel electrophoresis was used to analyze... [Objective] The aim was to study the changes of zymography in 6 kinds of isozymes after long-term subculture of Emmenopterys henryi Oliv.. [Method] Non-denaturing polyacrylamide gel electrophoresis was used to analyze isozyme patterns such as esterase (EST),acid phosphatase (ACP),ATP enzyme (ATPase),amylase (AMY),superoxide dismutase (SOD) and peroxidase (POD) in long-term subculture callus of Emmenopterys henryi Oliv. [Result] The research showed that there were differences among the 6 kinds of isozymes in embryogenic callus and non-embryogenic callus of Emmenopterys henryi Oliv.,and both levels could be taken as the basis for identification,the EST,ACP,and POD of non-embryogenic callus were significantly higher than embryogenic callus. The browning of non-embryogenic callus was non-level in the AMY,SOD and POD isozymes when was compared with normal non-embryogenic callus,while the EST,ACP and ATPase isozymes decreased; When the browning of embryogenic callus was contrasted with normal embryogenic callus,EST isozyme increased and the other 5 kinds of enzymes decreased. [Conclusion] The study provided theoretical basis for research morphological difference and browning of long-term tissue culture of Emmenopterys henryi Oliv.. 展开更多
关键词 Emmenopterys henryi Oliv. Callus Long-term subculture Isozyme Browning
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Effect of Diluents on the Extraction of Oxalic Acid by Trialkylphosphine Oxide 被引量:1
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作者 李玉鑫 王运东 戴猷元 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第1期143-148,共6页
In liquid-liquid solvent extraction processes, diluents have a strong influence on the extraction mechanism and efficiency. In this study, benzene, cyclohexane, trichloromethane, carbon tetrachloride, methyl isobutyl ... In liquid-liquid solvent extraction processes, diluents have a strong influence on the extraction mechanism and efficiency. In this study, benzene, cyclohexane, trichloromethane, carbon tetrachloride, methyl isobutyl ketone (MIBK), butyl acetate, and 1-octanol were used as diluents in the extraction of oxalic acid by trialkylphos-phine oxide (TRPO). The effects of extractant concentration, initial concentration of oxalic acid and diluent type on the extraction equilibrium partition coefficient are analyzed. The sequence of the extraction ability by different diluents is MIBK > butyl acetate > cyclohexane=benzene > carbon tetrachloride > 1-octanol > trichloromethane. Extraction mechanism was analyzed and extraction model parameters were evaluated. 展开更多
关键词 EXTRACTION reversible chemical cornplexation trialkylphosphine oxide oxalic acid DILUENT
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Ordered macroporous boron phosphate crystals as metal-free catalysts for the oxidative dehydrogenation of propane 被引量:8
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作者 Wen-Duo Lu Xin-Qian Gao +4 位作者 Quan-Gao Wang Wen-Cui Li Zhen-Chao Zhao Dong-Qi Wang An-Hui Lu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第12期1837-1845,共9页
Ordered macroporous materials with rapid mass transport and enhanced active site accessibility are essential for achieving improved catalytic activity.In this study,boron phosphate crystals with a three-dimensionally ... Ordered macroporous materials with rapid mass transport and enhanced active site accessibility are essential for achieving improved catalytic activity.In this study,boron phosphate crystals with a three-dimensionally interconnected ordered macroporous structure and a robust framework were fabricated and used as stable and selective catalysts in the oxidative dehydrogenation(ODH)of propane.Due to the improved mass diffusion and higher number of exposed active sites in the ordered macroporous structure,the catalyst exhibited a remarkable olefin productivity of^16 golefin gcat^-1 h^-1,which is up to 2–100 times higher than that of ODH catalysts reported to date.The selectivity for olefins was 91.5%(propene:82.5%,ethene:9.0%)at 515℃,with a propane conversion of 14.3%.At the same time,the selectivity for the unwanted deep-oxidized CO2 product remained less than 1.0%.The tri-coordinated surface boron species were identified as the active catalytic sites for the ODH of propane.This study provides a route for preparing a new type of metal-free catalyst with stable structure against oxidation and remarkable catalytic activity,which may represent a potential candidate to promote the industrialization of the ODH process. 展开更多
关键词 Ordered macroporous material Metal-free catalyst Boron phosphate Oxidative dehydrogenation PROPANE
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A Modified Oxidation Ditch with Additional Internal Anoxic Zones for Enhanced Biological Nutrient Removal 被引量:5
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作者 LIU Wei YANG Dianhai XU Li SHEN Changming 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第2期192-198,共7页
A novel modified pilot scale anaerobic oxidation ditch with additional internal anoxic zones was operated experimentally, aiming to study the improvement of biological nitrogen and phosphorus removal and the effect of... A novel modified pilot scale anaerobic oxidation ditch with additional internal anoxic zones was operated experimentally, aiming to study the improvement of biological nitrogen and phosphorus removal and the effect of enhanced denitrifying phosphorus removal in the process. Under all experimental conditions, the anaero- bic-oxidation ditch with additional internal anoxic zones and an internal recycle ratio of 200% had the highest nutrient removal efficiency. The effluent NH4 -N, total nitrogen (TN), PO3 -P and total phosphorus (TP) contents were 1.2 mg.L-1, 13 mg.L 1, 0.3 mg.L -1 and 0.4 mg.L-1, respectively, all met the discharge standards in China. The TN and TP removal efficiencies were remarkably improved from 37% and 50% to 65% and 88% with the presence of additional internal anoxic zones and internal recycle ratio of 200%. The results indicated that additional internal anoxic zones can optimize the utilization of available carbon source from the anaerobic outflow for denitrification. It was also found that phosphorus removal via the denitrification process was stimulated in the additional internal anoxic zones, which was beneficial for biological nitrogen and phosphorus removal when treating wastewater with a limited carbon source. However, an excess internal recycle would cause nitrite to accumulate in the system. This seems to be harmful to biological phosphorus removal. 展开更多
关键词 internal anoxic zones internal recycle carbon source NITRATE PHOSPHORUS
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Effects of phosphate precursors on morphology and oxygen evolution reaction activity of NiFe(oxy)hydroxide on nickel foams 被引量:2
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作者 Ran DUAN Ye-jun LI +4 位作者 Shu WANG Yong-gang TONG Horst-Günter RUBAHN Gu-fei ZHANG Wei-hong QI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第12期4050-4061,共12页
NiFe(oxy)hydroxides nanosheets were synthesized on nickel foams via co-precipitation and electrochemical activation. It is found that the phosphate precursors(Na_(3)PO_(4), Na_(2)HPO_(4)and NaH_(2)PO_(4)) have diverse... NiFe(oxy)hydroxides nanosheets were synthesized on nickel foams via co-precipitation and electrochemical activation. It is found that the phosphate precursors(Na_(3)PO_(4), Na_(2)HPO_(4)and NaH_(2)PO_(4)) have diverse effects on the morphology and thus the oxygen evolution reaction activity of the formed final catalysts. The resulting NiFe(oxy)hydroxides nanosheets prepared with Na_(2)HPO_(4)demonstrate a low overpotential of 205 m V to achieve a current density of 50 mA/cm^(2) with a Tafel slope down to 30 mV/dec in 1 mol/L KOH, and remain stable for 20 h during stability test. 展开更多
关键词 NiFe(oxy)hydroxides Fe-based phosphate oxygen evolution reaction electrochemical activation
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Soil Enzyme Activity Changes in Different-Aged Spruce Forests of the Eastern Qinghai-Tibetan Plateau 被引量:48
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作者 ZHANGYong-Mei ZHOUGuo-Yi +1 位作者 WUNing BAOWei-Kai 《Pedosphere》 SCIE CAS CSCD 2004年第3期305-312,共8页
Activities of selected soil enzymes (invertase, acid phosphatase, proteinase,catalase, peroxidase and polyphenoloxi-dase) were determined under different spruce forests withrestoration histories of 5, 13, 18, 23, 27 y... Activities of selected soil enzymes (invertase, acid phosphatase, proteinase,catalase, peroxidase and polyphenoloxi-dase) were determined under different spruce forests withrestoration histories of 5, 13, 18, 23, 27 years and an old growth forest over 400 years old in theeastern Qinghai-Tibetan Plateau, China, and their possible use as indicators of ecosystems healthwere analyzed. Plots 10 X 10 m with 4 replications were established to investigate three hypotheses:soil enzyme activities a) would increase with the restoration process; b) would be greater insurface soils than at lower depths; and c) would be correlated to selected physicochemicalproperties. Results showed that as the forests developed after restoration, invertase and peroxidaseactivities usually increased up to the 23 year point. Also soil enzyme activities were associatedwith surface soils and decreased with depths, suggesting that in earlier restoration stages surfaceaddition of organic fertilizer to soils might be more effective than additions at depth. In the 0-20cm soil, there were significant correlations (P < 0.01 or < 0.05) between some soil enzymeactivities and some selected chemical properties. Therefore, temporal changes in enzyme activitiesshould be included as an indicator when evaluating sustainable forest management practices. 展开更多
关键词 acid phosphatase CATALASE INVERTASE PEROXIDASE spruce forest (picea spp.)
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Recent developments in metal phosphide and sulfide electrocatalysts for oxygen evolution reaction 被引量:23
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作者 Lishan Peng Syed Shoaib Ahmad Shah Zidong Wei 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第10期1575-1593,共19页
Oxygen evolution reaction(OER),as an important half‐reaction involved in water splitting,has been intensely studied since the last century.Transition metal phosphide and sulfide‐based compounds have attracted increa... Oxygen evolution reaction(OER),as an important half‐reaction involved in water splitting,has been intensely studied since the last century.Transition metal phosphide and sulfide‐based compounds have attracted increasing attention as active OER catalysts due to their excellent physical and chemical characters,and massive efforts have been devoted to improving the phosphide and sulfide‐based materials with better activity and stability in recent years.In this review,the recent progress on phosphide and sulfide‐based OER electrocatalysts in terms of chemical properties,synthetic methodologies,catalytic performances evaluation and improvement strategy is reviewed.The most accepted reaction pathways as well as the thermodynamics and electrochemistry of the OER are firstly introduced in brief,followed by a summary of the recent research and optimization strategy of phosphide and sulfide‐based OER electrocatalysts.Finally,some mechanistic studies of the active phase of phosphide and sulfide‐based compounds are discussed to give insight into the nature of active catalytic sites.It is expected to indicate guidance for further improving the performances of phosphide and sulfide‐based OER electrocatalysts. 展开更多
关键词 Oxygen evolution reaction ELECTROCATALYSIS Metal phosphide Metal sulfide In situ oxidation Active component
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