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Differential pricing and production strategies for heterogeneous products under cannibalization and promotional effects
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作者 Aijun Liu Meiting Jing +2 位作者 Jie Miao Zengxian Li Yun Yang 《Journal of Management Science and Engineering》 2022年第4期608-629,共22页
This study examines the optimal pricing and production strategy of a closed-loop supply chain consisting of a manufacturer, a recycler, and consumers. Considering the cannibalization and promotion effects of remanufac... This study examines the optimal pricing and production strategy of a closed-loop supply chain consisting of a manufacturer, a recycler, and consumers. Considering the cannibalization and promotion effects of remanufactured products on new and secondhand products, we constructed Stackelberg game models under different scenarios. We analyze the impact of the changes in the two effects on the optimal prices and production strategies of the manufacturer and recycler, as well as their countermeasures. We find that (i) how the cannibalization and promotional effects influence the manufacturer and the recycler's pricing and production strategies differ under different scenarios;(ii) when the two effects exceed a threshold, the manufacturer abandons new or remanufactured products, and the recycler prefers to stop production on its new products or continue to remanufacture products;and (iii) the two effects always reduce the profits of the manufacturer and increase the profits of the recycler. 展开更多
关键词 Cannibalization effect promotional effect Heterogeneous products PRICING Production strategy
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Research Progress on the Growth-Promoting Effect of Plant Biostimulants on Crops
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作者 Qi Lu Longfei Jin +3 位作者 Cuiling Tong Feng Liu Bei Huang Dejian Zhang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第4期661-679,共19页
A Plant Biostimulant is any substance or microorganism applied to plants to enhance nutrition efficiency,abioticstress tolerance,and/or crop quality traits,regardless of its nutrient content.The application of Plant b... A Plant Biostimulant is any substance or microorganism applied to plants to enhance nutrition efficiency,abioticstress tolerance,and/or crop quality traits,regardless of its nutrient content.The application of Plant biostimulants(PBs)in production can reduce the application of traditional pesticides and chemical fertilizers and improvethe quality and yield of crops,which is conducive to the sustainable development of agriculture.An in-depthunderstanding of the mechanism and effect of various PBs is very important for how to apply PBs reasonablyand effectively in the practice of crop production.This paper summarizes the main classification of PBs;Thegrowth promotion mechanism of PBs was analyzed from four aspects:improving soil physical and chemical properties,enhancing crop nutrient absorption capacity,photosynthesis capacity,and abiotic stress tolerance;At thesame time,the effects of PBs application on seed germination,seedling vigor,crop yield,and quality were summarized;Finally,how to continue to explore and study the use and mechanism of PBs in the future is analyzedand prospected,to better guide the application of PBs in crop production in the future. 展开更多
关键词 Plant biostimulants growth promoting effect crop production
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Promoting effects of Fe_2O_3 to Pt electrocatalysts toward methanol oxidation reaction in alkaline electrolyte 被引量:1
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作者 宋桂花 杨海芳 +5 位作者 孙雅飞 王静怡 曲卫东 张强 马令娟 冯媛媛 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第3期554-563,共10页
Fe_2O_3 nanorods and hexagonal nanoplates were synthesized and used as the promoters for Pt electrocatalysts toward the methanol oxidation reaction(MOR) in an alkaline electrolyte.The catalysts were characterized by... Fe_2O_3 nanorods and hexagonal nanoplates were synthesized and used as the promoters for Pt electrocatalysts toward the methanol oxidation reaction(MOR) in an alkaline electrolyte.The catalysts were characterized by scanning electron microscopy,transmission electron microscopy,X-ray diffraction,X-ray photoelectron spectroscopy,cyclic voltammetry and chronoamperometry.The results show that the presence of Fe_2O_3 in the electrocatalysts can promote the kinetic processes of MOR on Pt,and this promoting effect is related to the morphology of the Fe_2O_3 promoter.The catalyst with Fe_2O_3 nanorods as the promoter(Pt-Fe_2O_3/C-R) exhibits much higher catalytic activity and stability than that with Fe_2O_3 nanoplates as the promoter(Pt-Fe_2O_3/C-P).The mass activity and specific activity of Pt in a Pt-Fe_2O_3/C-R catalyst are 5.32 A/mgpt and 162.7 A/m^2_(Pt),respectively,which are approximately 1.67 and 2.04 times those of the Pt-Fe_2O_3/C-P catalyst,and 4.19 and 6.16 times those of a commercial PtRu/C catalyst,respectively.Synergistic effects between Fe_2O_3 and Pt and the high content of Pt oxides in the catalysts are responsible for the improvement.These findings contribute not only to our understanding of the MOR mechanism but also to the development of advanced electrocatalysts with high catalytic properties for direct methanol fuel cells. 展开更多
关键词 PLATINUM Ferric oxide Promoting effect Methanol electrooxidation reaction Alkaline electrolyte
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A critical review on phytochemical profile and health promoting effects of mung bean (Vigna radiata) 被引量:9
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作者 Kumar Ganesan Baojun Xu 《Food Science and Human Wellness》 SCIE 2018年第1期11-33,共23页
The seeds and sprouts of mung bean are very common cruise in Asia.Evidence showed that bioactive compounds in mung bean have emerged as an increasing scientific interest due to their role in the prevention of degenera... The seeds and sprouts of mung bean are very common cruise in Asia.Evidence showed that bioactive compounds in mung bean have emerged as an increasing scientific interest due to their role in the prevention of degenerative diseases.All data of in vitro,in vivo and clinical studies of mung bean and its impact on human health were collected from a library database and electronic search.Botanical,phytochemical and pharmacological information was gathered and orchestrated.Remarkable studies have been demonstrated,showing the enhancement of metabolites in mung bean during the sprouting process,which possesses various health benefiting bioactive compounds.These compounds have been frequently attributed to their antioxidant,anti-diabetic,antimicrobial,anti-hyperlipidemic and antihypertensive effect,anti-inflammatory,and anticancer,anti-tumor and anti-mutagenic properties.In this critical review,we aimed to study the insight of the nutritional compositions,phytochemistry,and healthpromoting effects of mung bean and its sprouts.The various curative potential of mung bean provides successive preclinical outcomes in the field of drug discovery and this review strongly recommends that mung bean is an excellent nutritive legume,which modulates or prevents chronic degenerative diseases. 展开更多
关键词 Mung bean Nutritional composition PHYTOCHEMISTRY Health promoting effects
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Insight into the promotional mechanism of Cu modification towards wide-temperature NH3-SCR performance of NbCe catalyst 被引量:1
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作者 Dongqi An Yuyao Yang +4 位作者 Weixin Zou Yandi Cai Qing Tong Jingfang Sun Lin Dong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第10期301-309,共9页
A simple strategy of Cu modification was proposed to broaden the operation temperature window for NbCe catalyst.The best catalyst Cu0.010/Nb1Ce3 presented over 90%NO conversion in a wide temperature range of 200-400℃... A simple strategy of Cu modification was proposed to broaden the operation temperature window for NbCe catalyst.The best catalyst Cu0.010/Nb1Ce3 presented over 90%NO conversion in a wide temperature range of 200-400℃and exhibited an excellent H_(2)O or/and SO_(2) resistance at 275℃.To understand the promotional mechanism of Cu modification,the correlation among the"activity-structure-property"were tried to establish systematically.Cu species highly dispersed on NbCe catalyst to serve as the active component.The strong interaction among Cu,Nb and Ce promoted the emergence of NbO4 and induced more Bronsted acid sites.And Cu modification obviously enhanced the redox behavior of the NbCe catalyst.Besides,EPR probed the Cu species exited in the form of monomeric and dimeric Cu^(2+),the isolated Cu^(2+)acted as catalytic active sites to promote the reaction:Cu^(2+)-NO_(3)^(-)+NO(g)→Cu^(2+)-NO_(2)^(-)+NO_(2)(g).Then the generated NO_(2) would accelerate the fast-SCR reaction process and thus facilitated the lowtemperature deNO_(x) efficiency.Moreover,surface nitrates became unstable and easy to decompose after Cu modification,thus providing additional adsorption and activation sites for NH3,and ensuring the improvement of catalytic activity at high temperature.Since the NH3-SCR reaction followed by E-R reaction pathway efficaciously over Cu_(0.010)/Nb_(1)Ce_(3) catalyst,the excellent H_(2)O and SO_(2) resistance was as expected. 展开更多
关键词 NH_(3)-SCR NbCe catalyst Cu modification NO_(2)promoting effect Fast-SCR Flue gas
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MECHANISM OF PROMOTING EFFECTS OF RIBOFLAVIN DEFICIENCY ON CARCINOGENESIS OF NITROSAMINES (EFFECTS ON RAT LIVER GLUTATHIONE CONTENT)
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作者 乔长虹 郑素芳 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第4期40-42,共3页
The effects of riboflavin deficiency and simultaneously nitrosodimethylamine (NDMA) given by gastric intubation on the hepatic glutathione (GSH) content were examined in rats. On different days of the experiment, hepa... The effects of riboflavin deficiency and simultaneously nitrosodimethylamine (NDMA) given by gastric intubation on the hepatic glutathione (GSH) content were examined in rats. On different days of the experiment, hepatic GSH content of the riboflavin deficient rats decreased to 55-61% of the control rats. When NDMA was given 6 mg kg by gastric intubation to riboflavin deficient rats, hepatic GSH content decreased markedly to 39-43% of the control rats. After supplying riboflavin, hepatie GSH content of the deficient rats recovered to the level of the control rats. These results suggest that alterations of rat hepatic GSH content during riboflavin deficiency may imply as one of the promoting effects of riboflavin deficiency on the carcinogenesis of nitrosamines. 展开更多
关键词 GSH effects ON RAT LIVER GLUTATHIONE CONTENT MECHANISM OF PROMOTING effects OF RIBOFLAVIN DEFICIENCY ON CARCINOGENESIS OF NITROSAMINES NDMA
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Multidrug dissolvable microneedle patch for the treatment of recurrent oral ulcer 被引量:2
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作者 Yuqiong Wang An’an Sheng +7 位作者 Xinran Jiang Shanshan Yang Long Lin Mingzhu Yang Fengshuo Zhu Yongyan Hu Jian Li Lingqian Chang 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2023年第3期255-267,共13页
Recurrent oral ulcer is a painful oral mucosal disorder that affects 20%of the world’s population.The lack of a radical cure due to its unknown underlying cause calls for innovative symptomatic treatments.This work r... Recurrent oral ulcer is a painful oral mucosal disorder that affects 20%of the world’s population.The lack of a radical cure due to its unknown underlying cause calls for innovative symptomatic treatments.This work reports a hyaluronic acid-based dissolvablemicroneedle patch(ROUMNpatch,short for recurrent oral ulcer microneedle)loaded with dexamethasone acetate,vitamin C and tetracaine hydrochloride for the treatment of recurrent oral ulcers.The ROUMN patch shows enhancement in both the anti-inflammatory effect elicited by dexamethasone and the pro-proliferation effect of vitamin C.In vitro experiments show that ROUMN has a higher efficiency in suppressing lipopolysaccharide(LPS)-induced interleukin-6(IL-6)expression than dexamethasone alone.Cell proliferation and migrationwere also significantly promoted byROUMNcompared to vitamin C alone.The healing-promoting effect of ROUMN was also verified in vivo using an acetic acid-cauterized oral ulcer model in rats.ROUMN as a treatment accelerated the healing process of oral ulcers,shortening the total healing time to 5 days compared with the 7 days required by treatment using watermelon frost,a commonly used over-the-counter(OTC)drug for oral ulcers.The rapid dissolution of the hyaluronic acid-based microneedles and the superior healing-promoting effect of the drug combination could lead to a broad application prospect of the ROUMN patch in the treatment of recurrent oral ulcers. 展开更多
关键词 Recurrent oral ulcer Dissolvable microneedle Hyaluronic acid microneedle MULTIDRUG ANTI-INFLAMMATION Healing promoting effect
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Enhanced CO oxidation over potassium-promoted Pt/Al_2O_3 catalysts:Kinetic and infrared spectroscopic study 被引量:1
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作者 刘欢欢 贾爱平 +2 位作者 王瑜 罗孟飞 鲁继青 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第11期1976-1986,共11页
A series of K-promoted Pt/Al2O3 catalysts were tested for CO oxidation. It was found that the addition of K significantly enhanced the activity. A detailed kinetic study showed that the activation energies of the K-co... A series of K-promoted Pt/Al2O3 catalysts were tested for CO oxidation. It was found that the addition of K significantly enhanced the activity. A detailed kinetic study showed that the activation energies of the K-containing catalysts were lower than those of the K-free ones, particularly for catalysts with high Pt contents (51.6 k)/mol for 0.42K-2.0Pt/Al2O3 and 6:3.6 kJ/mol for 2.0Pt/Al2O3 ). The CO reaction orders were higher for the K-containing catalysts (about -0.2) than for the K-free ones (about -0.5), with the former having much lower equilibrium constants for CO adsorption than the latter. In situ Fourier-transform infrared spectroscopy showed that surface CO desorption from the 0.42K-2.0Pt/Al2O3 catalyst was easier than from 2.0Pt/Al2O3. The promoting effect of K was therefore caused by weakening of the interactions between CO and surface Pt atoms. This decreased coverage of the catalyst with CO and facilitated competitive O2 chemisorption on the Pt surface, and significantly lowered the reaction barrier between chemisorbed CO and O2 species. 展开更多
关键词 CO oxidation Potassium Kinetics Pt/Al2O3 catalyst Promoting effect
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Revalorization of CO2 for methanol production via ZnO promoted carbon nanofibers based Cu-ZrO2 catalytic hydrogenation 被引量:7
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作者 Israf Ud Din Maizatul S.Shaharun +2 位作者 A.Naeem S Tasleem Pervaiz Ahmad 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第12期68-76,共9页
A series of novel carbon nanofibers(CNFs)based Cu-ZrO2 catalysts were synthesized by deposition precipitation method.To investigate the influence of promoter,catalysts were loaded with 1,2,3 and 4 wt%ZnO and character... A series of novel carbon nanofibers(CNFs)based Cu-ZrO2 catalysts were synthesized by deposition precipitation method.To investigate the influence of promoter,catalysts were loaded with 1,2,3 and 4 wt%ZnO and characterized by ICP-OES,HRTEM,BET,N2O chemisorption,TPR,XPS and CO2-TPD techniques.The results revealed that physicochemical properties of the catalysts were strongly influenced by incorporation of ZnO to the parent catalyst.Copper surface area(SCu)and dispersion(DCu)were slightly decreased by incorporation of ZnO promoter.Nevertheless,SCuand DCuwere remarkably decreased when ZnO content was exceeded beyond 3 wt%.The catalytic performance was evaluated by using autoclave slurry reactor at a pressure and temperature of 30 bar and 180℃,respectively.The promotion of CuZrO2/CNFs catalyst with 3 wt%of ZnO enhanced methanol synthesis rate from 32 to 45 g kg^-1 h^-1.Notably,with the ZnO promotion the selectivity to methanol was enhanced to 92%compared to 78%of the un-promoted Cu-ZrO2/CNFs catalyst at the expense of a lowered CO2 conversion.In addition,the catalytic activity of this novel catalyst system for CO2 hydrogenation to methanol was compared with the recent literature data. 展开更多
关键词 Methanol synthesis Slurry reactor Promoter effect Chemisorption studies CNFs CO2 conversion
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Revealing the unexpected promotion effect of EuO_x on Pt/CeO_2 catalysts for catalytic combustion of toluene 被引量:8
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作者 Baoming Zhao Yanfei Jian +1 位作者 Zeyu Jiang Chi He 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第4期543-552,M0003,共11页
Pt/Eu2O3-CeO2 materials with different Eu concentrations were prepared and applied to toluene destruction,and the remarkable promotion impact of EuOx on Pt/CeO2 can be observed.The characterization results reveal that... Pt/Eu2O3-CeO2 materials with different Eu concentrations were prepared and applied to toluene destruction,and the remarkable promotion impact of EuOx on Pt/CeO2 can be observed.The characterization results reveal that the presence of EuOx significantly enhances the redox property,lattice O concentration,and Ce3+ ratio of the Pt/CeO2 material,which facilitates the dispersion and activity of Pt active sites and thus accelerates the decomposition process of toluene.Among all catalysts,a sample with an Eu content of 2.5 at.%(Pt/EC-2.5)possesses the best catalytic activity with 0.09 vol% of toluene completely destructed at 200 ℃ under a relatively high GHSV of 50000 h^-1.The possible reaction pathway and mechanism of toluene combustion over Pt/Eu2O3-CeO2 samples are presented according to in-situ DRIFTS,which confirms that the toluene oxidation process obeys the Mars-van Krevelen mechanism with aldehydes and ketones as primary organic intermediates. 展开更多
关键词 Pt/Eu2O3-CeO2 material Promotion effect TOLUENE Catalytic oxidation In-situ DRIFTS Reaction mechanism
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Promoting effect of super absorbent polymer on hydrate formation 被引量:8
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作者 Fei Long Shuanshi Fan Yanhong Wang Xuemei Lang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第3期251-254,共4页
The effect of super absorbent polymer(SAP) on the formation of tetrahydrofuran(THF) hydrate was studied by the successional cooling method.It was found that THF solution samples with 0.004 wt% and 0.03 wt% of SAP ... The effect of super absorbent polymer(SAP) on the formation of tetrahydrofuran(THF) hydrate was studied by the successional cooling method.It was found that THF solution samples with 0.004 wt% and 0.03 wt% of SAP formed THF hydrate completely during the same cooling process.The corresponding induction time was 16-29 min,14-31 min,respectively,which was obviously shorter than that of THF solution samples without SAP(25-62 min).It indicated that SAP accelerated the formation of THF hydrate.At the same time,the pictures of hydrate formation with and without SAP had been compared.It was found that SAP did not change the morphology of the hydrate.Finally,the mechanism of SAP promoting effect on the formation of THF hydrate was suggested. 展开更多
关键词 super absorbent polymer TETRAHYDROFURAN HYDRATE promoting effect
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Tuning the properties of Ni-based catalyst via La incorporation for efficient hydrogenation of petroleum resin 被引量:4
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作者 Qunhong Liu Jiangtao Yang +5 位作者 Hongwei Zhang Hongming Sun Shuzheng Wu Bingqing Ge Rong Wang Pei Yuan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第5期41-50,共10页
The hydrogenation of petroleum resin(PR)is an effective process to prepare high value-added hydrogenated PR(HPR).However,the preparation of non-noble metal-based catalysts with high catalytic activity for PR hydrogena... The hydrogenation of petroleum resin(PR)is an effective process to prepare high value-added hydrogenated PR(HPR).However,the preparation of non-noble metal-based catalysts with high catalytic activity for PR hydrogenation still remains a challenge.Herein,a La promoted Ni-based catalyst is reported through the thermal reduction of quaternary Ni La Mg Al-layered double hydroxides(Ni La Mg Al-LDHs).The incorporation of La is beneficial to the reduction and stability of Ni particles with reduced particle size,and the increased alkalinity effectively mitigates the breakage of molecular chains of PR.As a result,the La promoted Ni-based catalyst exhibits high catalytic activity and excellent stability for PR hydrogenation.A hydrogenation degree of 95.4%and 96.1%can be achieved for HC_(5)PR and HC_(9) PR with less reduced softening point,respectively.Notably,the hydrogenation degree still maintains at 92.7%even after 100 hours’reaction,much better than that without La incorporation or prepared using conventional impregnation method. 展开更多
关键词 Ni-based catalyst Layered double hydroxides Promotion effect Petroleum resin HYDROGENATION
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The Promotion Effect of Low-Molecular Hydroxyl Compounds on the Nano-Photoelectrocatalytic Degradation of Fulvic Acid and Mechanism 被引量:4
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作者 Yifan Dong Jinhua Li +1 位作者 Xuejin Li Baoxue Zhou 《Nano-Micro Letters》 SCIE EI CAS 2016年第4期320-327,共8页
A significant promotion effect of low-molecular hydroxyl compounds(LMHCs) was found in the nano-photoelectrocatalytic(NPEC) degradation of fulvic acid(FA),which is a typical kind of humic acid existing widely in natur... A significant promotion effect of low-molecular hydroxyl compounds(LMHCs) was found in the nano-photoelectrocatalytic(NPEC) degradation of fulvic acid(FA),which is a typical kind of humic acid existing widely in natural water bodies,and its influence mechanism was proposed.A TiO_2 nanotube arrays(TNAs) material is served as the photoanode.Methanol,ethanediol,and glycerol were chosen as the representative of LMHCs in this study.The adsorption performance of organics on the surface of TNAs was investigated by using the instantaneous photocurrent value.The adsorption constants of FA,methanol,ethanediol,and glycerol were 43.44,19.32,7.00,and 1.30,respectively,which indicates that FA has the strongest adsorption property.The degradation performance of these organics and their mixture were observed in a thin-layer reactor.It shows that FA could hardly achieve exhausted mineralization alone,while LMHCs could be easily oxidized completely in the same condition.The degradation degree of FA,which is added LMHCs,improves significantly and the best promotion effect is achieved by glycerol.The promotion effect of LMHCs in the degradation of FA could be contributed to the formation of a tremendous amount of hydroxyl radicals in the NPEC process.The hydroxyl radicals could facilitate the complete degradation of both FA and its intermediate products.Among the chosen LMHCs,glycerol molecule which has three hydroxyls could generate the most hydroxyl radicals and contribute the best effective promotion.This work provides a new way to promote the NPEC degradation of FA and a direction to remove humus from polluted water. 展开更多
关键词 Fulvic acid Nano-photoelectrocatalytic degradation Promotion effect Low-molecular hydroxyl compounds
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Electrochemical recycling of Pd and Ag from simulated high-level liquid waste 被引量:3
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作者 You-bin WANG Rui ZOU +2 位作者 Yue-zhou WEI Tsuyoshi ARAI Toyohisa FUJITA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第3期1031-1040,共10页
For the recycling of Pd and Ag from high-level liquid waste(HLLW), the electrochemical behaviors of Pd and Ag in the simulated HNO_(3) solutions were investigated by cyclic voltammetry and potentiostatic deposition.Sc... For the recycling of Pd and Ag from high-level liquid waste(HLLW), the electrochemical behaviors of Pd and Ag in the simulated HNO_(3) solutions were investigated by cyclic voltammetry and potentiostatic deposition.Scanning electron microscopy(SEM) and X-ray diffraction(XRD) were used to-observe the deposits morphology and to evaluate their composition. The results indicate that the formation of NO_(2)^(-)electrodeposited. When Pd and Ag are electrodeposited together, more metals are gained in the same time, and the deposited Ag does not dissolve in this situation. The metals are electrodeposited completely at the potentials from -0.4 to -0.6 V(vs MSE) and the deposits contai-n Ag and PdHx. The electrodeposition of Pd can boost h-ydrogen evolution,and then the reaction between H;and NO_(2)^(-)is sped up, thereby lowering the concentration of NO_(2)^(-)and inhibiting the dissolution of Ag. 展开更多
关键词 ELECTRODEPOSITION metals recovery nitrite generation promoting effect morphology characteristics
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Promoting effect of chloride ions on selective oxidation of methanol to methyl formate over zirconia-supported ruthenium oxide catalysts 被引量:2
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作者 Weizhen Li Hongpeng Zhang +1 位作者 Xiaohui He Haichao Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第3期512-516,共5页
The effect of chloride ions on a monoclinic ZrO2-supported RuOx (RuOx/m-ZrO2) catalyst with a Ru surface density of 0.3 Ru/nm2 was studied in the selective oxidation of methanol to methyl formate (MF) at a low tem... The effect of chloride ions on a monoclinic ZrO2-supported RuOx (RuOx/m-ZrO2) catalyst with a Ru surface density of 0.3 Ru/nm2 was studied in the selective oxidation of methanol to methyl formate (MF) at a low temperature of 373 K. The m-ZrO2 support was Cl-free, and Cl- ions were introduced into the RuOx/m-ZrO2 catalyst by impregnation with zirconium oxychloride or ammonium chloride and subsequent thermal treatment in air at 673 K. The structures of these catalysts were characterized by X-ray diffraction, Raman and X-ray photoelectron spectroscopies. Their reducibility was probed by temperature-programmed reduction in H2. The RuOx domains were present as highly dispersed Rut42- structure on m-ZrO2 with similar reducibility for the RuOx/m-ZrO2 samples irrespective of modification with or without Cl ions. Introduction of appropriate amounts of zirconium oxychloride into RuOx/m-ZrO2 led to a remarkable increase in the methanol oxidation rate and MF selectivity, whereas introduction of ammonium chloride or zirconyl nitrate significantly inhibited the catalytic performance of RuOx/m-ZrO2. The promoting effect of Cl- ions derived from zirconium oxychloride can be tentatively attributed to their roles in facilitating the adsorption of methanol and desorption of MF product or its intermediates. This finding provides novel insights into the promoting effect of Cl- ions on oxides-based catalysts for selective oxidation reactions. 展开更多
关键词 methanol oxidation ruthenium oxide monoclinic zirconia chloride promoting effect methyl formate
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The Biological Promotion Effect of a new Biological Promotive Ceramsite 被引量:2
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作者 邱珊 马放 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第4期604-608,共5页
Tourmaline can promote the growth of microorganisms under the temperature less than 900 ℃ by experiment. However, this promotion effect will vanish at 900 ℃ as a result of denaturation. Through the XRD analysis the ... Tourmaline can promote the growth of microorganisms under the temperature less than 900 ℃ by experiment. However, this promotion effect will vanish at 900 ℃ as a result of denaturation. Through the XRD analysis the crystal form change can explain the vanishment of tourmaline’s biological promotion effect at high temperature. Therefore, tourmaline as a biological promoter was used to prepare a kind of biological promotive ceramsite with the surface area of 7.914 m2/g, pore volume of 0.1002 mg/L, superficial pH value of 7.8, Zeta potential of 25 mV, unit water absorption of 0.1365 g/g, biocompatibility of 0.023 A/g and SICE of 0.8456. The experimental results show that the biomass of biological promotive ceramsite is 3.58 times more than that of ordinary ceramsite, and the treatment effect of the biological promotive ceramsite is better than the ordinary ceramsite. These features of this new biological promotive ceramsite makes it a preferable biovector. 展开更多
关键词 TOURMALINE biological promotion effect DENATURATION COMPARISON
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A new insight into the promoting effects of transition metal phosphides in methanol electrooxidation 被引量:3
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作者 Junjie Ding Shaojie Jing +8 位作者 Changqing Yin Chaogang Ban Kaiwen Wang Xue Liu Youyu Duan Yuxin Zhang Guang Han Liyong Gan Jinsong Rao 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第6期200-205,共6页
The construction of highly active catalysts for methanol oxidation reaction(MOR)is central to direct methanol fuel cells.Tremendous progress has been made in transition metal phosphides(TMPs)based catalysts.However,TM... The construction of highly active catalysts for methanol oxidation reaction(MOR)is central to direct methanol fuel cells.Tremendous progress has been made in transition metal phosphides(TMPs)based catalysts.However,TMPs would be partially damaged and transformed into new substances(e.g.,Pt-M-P composite,where M represents a second transition metal)during Pt deposition process.This would pose a large obstacle to the cognition of the real promoting effects of TMPs in MOR.Herein,Co_(2)P co-catalysts(Pt-P/Co_(2)P@NPC,where NPC stands for N and P co-doped carbon)and Pt-Co-P composite catalysts(Pt-CoP/NPC)were controllably synthesized.Electrocatalysis tests show that the Pt-Co-P/NPC exhibits superior MOR activity as high as 1016 m A/mg_(Pt),significantly exceeding that of Pt-P/Co_(2)P@NPC(345 m A/mg_(Pt)).This result indicates that the promoting effect is ascribed primarily to the resultant Pt-Co-P composite,in sharply contrast to previous viewpoint that Co_(2)P itself improves the activity.Further mechanistic studies reveal that Pt-Co-P/NPC exhibits much stronger electron interaction and thus manifesting a remarkably weaker CO absorption than Pt-P/Co_(2)P@NPC and Pt/C.Moreover,Pt-Co-P is also more capable of producing oxygen-containing adsorbate and thus accelerating the removal of surface-bonded CO^(*),ultimately boosting the MOR performance. 展开更多
关键词 Promoting effect Transition metal phosphides Pt-Co-P composite Catalytic mechanisms Methanol oxidation reaction
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Iridium-based catalysts for oxygen evolution reaction in acidic media:Mechanism,catalytic promotion effects and recent progress 被引量:4
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作者 Chunyan Wang Alex Schechter Ligang Feng 《Nano Research Energy》 2023年第2期151-181,共31页
Iridium(Ir)-based catalysts are highly efficient for the anodic oxygen evolution reaction(OER)due to high stability and anti-corrosion ability in the strong acid electrolyte.Recently,intensive attention has been direc... Iridium(Ir)-based catalysts are highly efficient for the anodic oxygen evolution reaction(OER)due to high stability and anti-corrosion ability in the strong acid electrolyte.Recently,intensive attention has been directed to novel,efficient,and low-cost Ir-based catalysts to overcome the challenges of their application in the water electrolysis technique.To make a comprehensive understanding of the recently developed Ir-based catalysts and their catalytic properties,the mechanism and catalytic promotion principles of Ir-based catalysts were discussed for OER in the acid condition aimed for the proton exchange membrane water electrolyzer(PEMWE)in this review.The OER catalytic mechanisms of the adsorbate evolution mechanism and the lattice oxygen mechanism were first presented and discussed for easy understanding of the catalytic mechanism;a brief perspective analysis of promotion principles from the aspects of geometric effect,electronic effect,synergistic effect,defect engineering,support effect was concluded.Then,the latest progress and the practical application of Ir-based catalysts were introduced in detail,which was classified into the varied composition of Ir catalyst in terms of alloys,hetero-element doping,perovskite,pyrochlore,heterostructure,core-shell structure,and supported catalysts.Finally,the problems and challenges faced by the current Ir-based catalyst in the acidic electrolyte were put forward.It is concluded that highly efficient catalysts with low Ir loading should be developed in the future,and attention should be paid to probing the structural and performance correlation,and their application in real PEMWE devices.Hopefully,the current effort can be helpful in the catalysis mechanism understanding of Ir-based catalysts for OER,and instructive to the novel efficient catalysts design and fabrication. 展开更多
关键词 Ir-based catalysts catalytic promotion effects oxygen evolution reaction acidic media
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Effect of Low Concentration of Yttrium on Physiological Characteristics of Cucumber (Cucumis Sativus L.)
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作者 王烁 陈丹 +3 位作者 秦兆江 董振宇 鞠明超 解冰凝 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第S2期236-241,共6页
There is no doubt that rare earth elements stand an important position among the essential elements of plant growth and it is long time since they are first used as plant growth promoters. Given their effects on micro... There is no doubt that rare earth elements stand an important position among the essential elements of plant growth and it is long time since they are first used as plant growth promoters. Given their effects on microstructure, most reports are focused on the toxicology rather than promotion. Using cucumis sativus L. (Jin Chun No.5) as experiment material, we try to find out the nutritional effects of low Y3+ concentrations on cucumber seedlings′ leaves. The present paper suggests that the rare earth elements act as micronutrients at low concentrations while they give rise to toxicity at high concentration. Benefits defeat toxicity with concentration ranging from 5 to 25 μmol·L-1. Through careful study, at the Y(NO3)3 concentration of 10 μmol·L-1 the content of chlorophyll as well as the activities of SOD, Cu-Zn SOD and the POD are the highest. It indicates 10 μmol·L-1 is the optimum concentration of yttrium for promoting the cucumber growth. 展开更多
关键词 rare earth elements YTTRIUM physiological characteristics promoting effects cucumis sativus L.
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Interaction of Each Component in Ni-Ln_2O_3/γ-Al_2O_3 System
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作者 郝茂荣 冯文林 安智华 《Journal of Rare Earths》 SCIE EI CAS CSCD 2001年第4期255-259,共5页
The surface functions produced by adding 14 rare earth oxides in Ni/γ Al 2O 3 system were determined by BET, gas chromatography, infrared spectroscopy, XRD, SEM, X ray electronic energy spectrum etc, and research... The surface functions produced by adding 14 rare earth oxides in Ni/γ Al 2O 3 system were determined by BET, gas chromatography, infrared spectroscopy, XRD, SEM, X ray electronic energy spectrum etc, and researched contrastively. The results show that the addition of rare earth oxides changes the property of catalyst surface. It is of benefit to increasing the number of active center of the catalyst and the surface acidity of the catalyst, decreasing the surface carbon deposit during the reaction. Moreover, the addition of rare earth oxides influences the electronic state of nickel atoms on the surface directly and produces electronic effect. The effect is different for each rare earth element. 展开更多
关键词 rare earths NiLn 2O 3/γ Al 2O 3 catalyst METHANATION rare earth promoter effects
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