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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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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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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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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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PROMOTING EFFECT OF TiO_X OVERLAYER ON THE DISSOCIATION OF CO ON Fe(110)
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作者 Jun Zhuo DENG Hong Li WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第2期167-170,共4页
The adsorption of CO on Fe(110)with different coverages of tita- nia has been studied by AES,XPS,UPS.It is proposed that the adsorption sites of CO in this system are not only blocked by the deposited TiO_X,but also b... The adsorption of CO on Fe(110)with different coverages of tita- nia has been studied by AES,XPS,UPS.It is proposed that the adsorption sites of CO in this system are not only blocked by the deposited TiO_X,but also by the products of the dissociation of CO which is promoted by the deposited TiO_X. 展开更多
关键词 110 IML promoting effect OF TiO_X OVERLAYER ON THE DISSOCIATION OF CO ON Fe CO TIO
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An empirical study on the green effects of new energy vehicle promotion in the context of global carbon neutrality
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作者 Xuan Gu Meng Wang Jiang Wu 《Chinese Journal of Population,Resources and Environment》 2022年第4期332-340,共9页
In the context of global carbon neutrality,new energy vehicle promotion(NEVP)has become an important means of reducing carbon emissions.This paper constructs a theoretical model and uses panel data on NEVP in 21 count... In the context of global carbon neutrality,new energy vehicle promotion(NEVP)has become an important means of reducing carbon emissions.This paper constructs a theoretical model and uses panel data on NEVP in 21 countries from 2012 to 2018 to empirically examine the green effect of NEVP.The results indicate the following:(1)NEVP significantly reduces greenhouse gases emissions,and the green effect can be transmitted and diffused through a direct path.(2)Replacing fuel-fired vehicles and accelerating the end-of-life vehicle scrapping process significantly conducted the green effect,and aggravating traffic congestion was not statistically significant.(3)The transmission mechanism of the green effect is regulated by regional economic heterogeneity.In regions with better development of fuel-fired vehicles,the transmission of the green effect is subject to the elimination of fuel-fired vehicles and traffic congestion governance,and the transmission efficiency is low.However,regions with a relatively weak fuel-fired automobile industry foundation show a strong“advantage of backwardness”,and the green effect is more prominent.This means that global NEVP should be further accelerated to achieve the green effect and the goal of global carbon neutrality. 展开更多
关键词 New energy vehicle promotion(NEVP) Green effect transmission mechanism Regional economic heterogeneity Moderated multiple mediation model
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THE PROMOTING EFFECT OF FLUORIDE TO OCM OCTALYST ZrO_2-BaF_2
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作者 Zi Sheng CHAO Xiao Ping ZHOU +3 位作者 Shui Ju WANG Fu Chun Xu Hui Lin WAN K.R.TSAI (Department of Chemistry, Xiamen University, Xiamen 361005) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第8期685-686,共2页
THE PROMOTING EFFECT OF FLUORIDE TO OCM OCTALYST ZrO;-BaF;THEPROMOTINGEFFECTOFFLUORIDETOOCMOCTALYSTZrO;-BaF;¥Z... THE PROMOTING EFFECT OF FLUORIDE TO OCM OCTALYST ZrO;-BaF;THEPROMOTINGEFFECTOFFLUORIDETOOCMOCTALYSTZrO;-BaF;¥ZiShengCHAO;Xi... 展开更多
关键词 OCM THE promoting effect OF FLUORIDE TO OCM OCTALYST ZrO2-BaF2
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The effect of using in ternet web site in promoting non-remunerated blood donation
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《中国输血杂志》 CAS CSCD 2001年第S1期324-,共1页
关键词 The effect of using in ternet web site in promoting non-remunerated blood donation
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Determination of Growth-promoting and Antagonistic Action of Endophytic Bacteria Strains Itb57 and Itb295 of Tobacco 被引量:1
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作者 汪莹 李小松 +1 位作者 胡建新 马冠华 《Plant Diseases and Pests》 CAS 2011年第1期46-48,共3页
[ Objective ] The paper was to study the growth-promoting and antagonistic action of endophytic bacteria strains Itb57 and Itb295 of tobacco to explore their functions in biological control. [ Method] The growth-promo... [ Objective ] The paper was to study the growth-promoting and antagonistic action of endophytic bacteria strains Itb57 and Itb295 of tobacco to explore their functions in biological control. [ Method] The growth-promoting effects of bacterial suspension ~ff endophytic bacteria Itb57 and Itb295 on tobacco seedling un- der different treatment modes were studied using potting method in greenhouse. The antagonistic action of bacterial suspension of endophytic bacteria Itb57 and Itb295 on Phytophthora nicotianae, Alternaria alternata and Botrytis cinerea were measured by duel culture method. [ Result] Bacterial suspensions of enduphytic bacteria Itb57 and Itb295 had certain growth-promoting effects on tobacco seedling, which could significantly increase the fresh weight and dry weight in aerial part; the growth-promoting effect of soaking + spraying and irrigating treatment was the best. Itb57 strain had good antagonistic action against P. nicotianae. A. alterna- ta and B. cinerea, while Itb295 strain only had good antifungal effect against P. nicotianae. [ Conclusion] The results provided basis for the study and application of tobacco endophytic bacteria strains Itb57 and Itb295 in biocontrol of tobacco diseases. 展开更多
关键词 TOBACCO Endophytic bacteria Growth-promoting effect Antagonistic activity
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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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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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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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Evaluation of the Effectiveness of Workplace Health Promotion Programs from 2000 to 2020: Literature Review 被引量:1
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作者 Siguero María-Ángeles Jerónimo Maqueda +2 位作者 Marqués Francisco Sagües María-Jesús Solé María-Dolores 《Open Journal of Preventive Medicine》 2021年第4期113-131,共19页
Introduction. Recognition of best practices in workplace health promotion is an important task that significantly affects the expansion of those programs. Once the program has been developed, its effectiveness becomes... Introduction. Recognition of best practices in workplace health promotion is an important task that significantly affects the expansion of those programs. Once the program has been developed, its effectiveness becomes the most critical point of evaluation to guarantee achievements in the improvement of workers’ health. Objectives. To identify the practices for evaluating the effectiveness of workplace health promotion programs. Material and Methods: A search was performed on MEDLINE through PubMed with the MeSH: “Occupational Health”, “Health Promotion” and “Program Evaluation”, from the year 2000 to the year 2020 for studies with the following designs: Meta-analyses, Systematic reviews, Randomized Clinical Trials and Clinical Trials. Results: The most common topic of workplace health promotion programs (WHP) was increasing physical activity and avoiding a sedentary lifestyle, followed by stress management and finally smoking cessation and musculoskeletal disorders. The post-intervention measurements were most often done at 6 months and 12. The most commonly used indicators were the number of steps, weight, BMI, % body fat, waist circumference, blood pressure, sedentary time, level of physical activity and time of moderate-vigorous physical activity, daily energy output, life purpose, life satisfaction, mood and stress level. Conclusions: Although a great variability was observed in the evaluation of WHP programs, there were also common aspects. These results will help with designing WHP programs and defining evidence-based evaluation of their effectiveness. It is important to remember that WHP programs must be customized, taking into consideration the needs of each organization’s workforce. 展开更多
关键词 Occupational Health Health promotion effectiveness Evaluation
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Dynamic Promotional Resource Allocation for Segment Specific and Spectrum Effect of Promotion for a Product Line Incorporating Repeat Purchase Behavior 被引量:1
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作者 Prakash Chandra Jha Prerna Manik Anshu Gupta 《American Journal of Operations Research》 2013年第3期350-362,共13页
Promotion is an essential element in the marketing mix. It is used by businesses to inform, influence and persuade customers to adopt the products and services they offer. Without promotion, business would be stagnant... Promotion is an essential element in the marketing mix. It is used by businesses to inform, influence and persuade customers to adopt the products and services they offer. Without promotion, business would be stagnant and lack substantial growth because the brands would have low visibility in the market. Moreover, today’s vast and assorted markets comprise of customers with different needs and varied behavior. So it is rarely possible for companies to satisfy all customers by treating them alike. Thus there arises a need to divide the market into segments having customers with similar traits/characteristics. After identifying appropriate market segments, firms can design differentiated promotional campaigns for each segment. At the same time there can be a mass market promotional campaign that reaches different segments with a fixed spectrum. Also since promotional effort resources are limited, one must use them judiciously. In this paper, we formulate mathematical programming problem under repeat purchase scenario, which optimally allocates mass promotional effort resources and differentiated promotional effort resources across the segments dynamically in order to maximize the overall sales obtained from multiple products of a product line under budgetary and minimum sales aspiration level constraint on each product under consideration in each segment. The planning horizon is divided into multi periods, the adoption pattern of each product in each segment is observed in every subinterval and accordingly promotional effort allocations are determined for the next period till we reach the end of planning period. The optimization model has been further extended to incorporate minimum aspiration level constraints on total sales for each product under consideration from all the segments taken together. The non linear programming problem so formulated is solved using differential evolution approach. A numerical example has been discussed to illustrate applicability of the model. 展开更多
关键词 MARKET Segmentation DIFFERENTIATED MARKET promotION Mass MARKET promotION SPECTRUM effect promotional Effort Allocation REPEAT Purchase Product Line Non Linear Programming Problem Differential Evolution
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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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Proximity Effect of Fe-Zn Bimetallic Catalysts on CO_(2) Hydrogenation Performance 被引量:3
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作者 Shengkun Liu Qiao Zhao +5 位作者 Xiaoxue Han Chongyang Wei Haoting Liang Yidan Wang Shouying Huang Xinbin Ma 《Transactions of Tianjin University》 EI CAS 2023年第4期293-303,共11页
The interaction between a promoter and an active metal crucially impacts catalytic performance.Nowadays,the influence of promoter contents and species has been intensively considered.In this study,we investigate the e... The interaction between a promoter and an active metal crucially impacts catalytic performance.Nowadays,the influence of promoter contents and species has been intensively considered.In this study,we investigate the effect of the iron(Fe)-zinc(Zn)proximity of Fe-Zn bimetallic catalysts on CO_(2)hydrogenation performance.To eliminate the size effect,Fe_(2)O_(3)and ZnO nanoparticles with uniform size are first prepared by the thermal decomposition method.By changing the loading sequence or mixing method,a series of Fe-Zn bimetallic catalysts with different Fe-Zn distances are obtained.Combined with a series of characterization techniques and catalytic performances,Fe-Zn bimetallic proximity for compositions of Fe species is discussed.Furthermore,we observe that a smaller Fe-Zn distance inhibits the reduction and carburization of the Fe species and facilitates the oxidation of carbides.Appropriate proximity of Fe and Zn(i.e.,Fe_1Zn_(1)-imp and Fe_(1)Zn_(1)-mix samples)results in a suitable ratio of the Fe_5C_(2)and Fe_(3)O_(4)phases,simultaneously promoting the reverse water-gas shift and Fischer-Tropsch synthesis reactions.This study provides insight into the proximity effect of bimetallic catalysts on CO_(2)hydrogenation performance. 展开更多
关键词 CO_(2)hydrogenation Fe-based catalyst promotER Proximity effect
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Promotion effect of adsorbed water/OH on the catalytic performance of Ag/activated carbon catalysts for CO preferential oxidation in excess H_2
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作者 Yuanyuan Guo Limin Chen +2 位作者 Ding Ma Daiqi Ye Bichun Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第4期591-598,共8页
Activated carbon (AC) supported silver catalysts were prepared by incipient wetness impregnation method and their catalytic performance for CO preferential oxidation (PROX) in excess H2 was evaluated. Ag/AC cataly... Activated carbon (AC) supported silver catalysts were prepared by incipient wetness impregnation method and their catalytic performance for CO preferential oxidation (PROX) in excess H2 was evaluated. Ag/AC catalysts, after reduction in H2 at low temperatures (≤200 ℃) following heat treatment in He at 200 ℃ (He200H200), exhibited the best catalytic properties. Temperature-programmed desorption (TPD), X-ray diffraction (XRD) and temperature-programmed reduction (TPR) results indicated that silver oxides were produced during heat treatment in He at 200 ℃ which were reduced to metal silver nanoparticles in H2 at low temperatures (≤200 ℃), simultaneously generating the adsorbed water/OH. CO conversion was enhanced 40% after water treatment following heat treatment in He at 600 ℃. These results imply that the metal silver nanoparticles are the active species and the adsorbed water/OH has noticeable promotion effects on CO oxidation. However, the promotion effect is still limited compared to gold catalysts under the similar conditions, which may be the reason of low selectivity to CO oxidation in PROX over silver catalysts. The reported Ag/AC-S-He catalyst after He200H200 treatment displayed similar PROX of CO reaction properties to Ag/SiO2. This means that Ag/AC catalyst is also an efficient low-temperature CO oxidation catalyst. 展开更多
关键词 promotion effect adsorbed water/OH Ag/activated carbon (Ag/AC) catalysts CO preferential oxidation (PROX)
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Evaluation on Inducible Effect of pOp6 Promoter in Transgenic Rice
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作者 Rouyi CHEN Changxiang ZHENG +2 位作者 Jiang CHENG Minna PAN Mariena KETUDAT-CAIRNS 《Agricultural Science & Technology》 CAS 2014年第5期742-744,共3页
In order to analyze the Oslbglu4 phenotype, the inducible promoter of the transgenic rice which knock-down the Oslbglu4 expression was assessed. The result showed that 30 μM dexamethasone(DEX) had the stronger indu... In order to analyze the Oslbglu4 phenotype, the inducible promoter of the transgenic rice which knock-down the Oslbglu4 expression was assessed. The result showed that 30 μM dexamethasone(DEX) had the stronger induction effect than 10 μM DEX by β-Glucuronidase (GUS) staining, qRT-PCR further verified the Oslbglu4 gene deletion. The effect of DEX and its solvent absolute ethanol on seed development was measured, and no significant effect was observed. The conclusion is that final concentration of DEX at 30 μM is suitable for pOp6 promoter induction. 展开更多
关键词 POp6 promoter GUS activity Inducible effect
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