Dear Editor, Lithium-ion(Li-ion) battery has become a promising source to supply and absorb energy/power for many energy-transportation applications. However, Li-ion battery capacity would inevitably degrade over time...Dear Editor, Lithium-ion(Li-ion) battery has become a promising source to supply and absorb energy/power for many energy-transportation applications. However, Li-ion battery capacity would inevitably degrade over time, making its related ageing prediction necessary.展开更多
Single-atom catalysts have been applied in many processes recently.The difference of their kinetic behavior compared to the traditional heterogeneous catalysts has not been extensively discussed yet.Herein a complete ...Single-atom catalysts have been applied in many processes recently.The difference of their kinetic behavior compared to the traditional heterogeneous catalysts has not been extensively discussed yet.Herein a complete catalytic cycle of CH4 combustion assuming to be confined at isolated single sites of the Co3O4(110)surface is computationally compared with that on multi sites.The macroscopic kinetic behaviors of CH4 combustion on Co3O4(110)is systematically and quantitatively compared between those on the single site and multi sites utilizing kinetic Monte Carlo simulations upon the energetic information from the PBE+U calculation and statistic mechanics.The key factors governing the kinetics of CH4 combustion are disclosed for both the catalytic cycles respectively following the single-site and multi-site mechanisms.It is found that cooperation of multi active sites can promote the activity of complete CH4 combustions substantially in comparison to separated single-site catalyst whereas the confinement of active sites could regulate the selectivity of CH4 oxidation.The quantitative understanding of catalytic mechanism paves the way to improve the activity and selectivity for CH4 oxidation.展开更多
In comparison to studies investigating the roles of 5-HT1, 5-HT2 and 5-HT3 receptors in aggressive behaviour there is a dearth of material examining the function of 5-HT4 receptors in this behaviour. In view of this, ...In comparison to studies investigating the roles of 5-HT1, 5-HT2 and 5-HT3 receptors in aggressive behaviour there is a dearth of material examining the function of 5-HT4 receptors in this behaviour. In view of this, the current study examined the effects of the 5-HT4 receptor partial agonist RS 67333 and antagonist RS 39604 in murine agonistic behaviour. RS 67333 failed to produce any significant changes in the offensive. Significant variation in the frequency of evade behaviour was detected but this occurred between treatment groups rather than with controls. Interestingly, both the frequency and duration of stretched attend behaviour were increased by RS 67333 0.1 mg/kg, a result indicative of increased risk assessment. The administration of RS 39604 (0.01 - 1 mg/kg) produced significant variation in the fre-quency and duration of following, and aggressive grooming. Frozen crouch behaviour was also increased significantly at 0.1 mg/kg. It is concluded that since the 5-HT4 receptor ligands employed in this study produced very few significant behavioural effects across the treatment groups, 5-HT4 receptors do not play a role in the modulation of murine aggressive behaviour.展开更多
In a system consisting of an electron and a highly-charged ion,interaction with the radiation field is important.This means radiation-damping effects must be accurately taken into account.The present work discusses th...In a system consisting of an electron and a highly-charged ion,interaction with the radiation field is important.This means radiation-damping effects must be accurately taken into account.The present work discusses the radiation-damping effect in the processes of photoionization,radiative recombination,and electron scattering.展开更多
Cloud computing has created a paradigm shift that affects the way in which business applications are developed. Many business organizations use cloud infrastructures as platforms on which to deploy business applicatio...Cloud computing has created a paradigm shift that affects the way in which business applications are developed. Many business organizations use cloud infrastructures as platforms on which to deploy business applications. Increasing numbers of vendors are supplying the cloud marketplace with a wide range of cloud products. Different vendors offer cloud products in different formats. The cost structures for consuming cloud products can be complex. Finding a suitable set of cloud products that meets an application’s requirements and budget can be a challenging task. In this paper, an ontology-based resource mapping mechanism is proposed. Domain-specific ontologies are used to specify high-level application’s requirements. These are then translated into high-level infrastructure ontologies which then can be mapped onto low-level descriptions of cloud resources. Cost ontologies are proposed for cloud resources. An exemplar media transcoding and delivery service is studied in order to illustrate how high-level requirements can be modeled and mapped onto cloud resources within a budget constraint. The proposed ontologies provide an application-centric mechanism for specifying cloud requirements which can then be used for searching for suitable resources in a multi-provider cloud environment.展开更多
This paper discusses and critically reviews the causes and consequences of global standardization and local adaptation of marketing strategies.The scope of the literature review is in the fields of international marke...This paper discusses and critically reviews the causes and consequences of global standardization and local adaptation of marketing strategies.The scope of the literature review is in the fields of international marketing,international trade,and corporate strategic management.It also aims to emphasize finding gaps after reading the literature.Even though the studies’scope is extensive,this paper limits the reach:firstly,it introduces the standardization and local adaptation,discusses the advantages and disadvantages of both by researchers.At the same time,untangle the relationship between international marketing strategy and marketing mix.Secondly,it is divided into macro and micro to collate and analyze the leading factors affecting international strategy,so that the cross-market fit of global marketing tactic can be realised.Finally,focus on the KPI.The indicators of financial return were selected as the review from the factors representing the intuitive development level of the company.The goal was to concentrate on the mutual feedback and adjustment between the standardization/adaptation and performance of multinational companies.Among them,the diversities between developed and emerging markets are interspersed in each link.As this difference is a trend that scholars have begun to notice in recent years.Although many existed bibliographies are revolved around particular multinational companies or regions to assessment,this paper will focus on the impact of practical research article review and evaluation.It would not involve specific corporate and country.展开更多
The induction generator effect(IGE)and the openloop modal proximity(OLMP)are two different reasons why subsynchronous oscillations(SSOs)in a series-compensated power system(SCPS)may occur.The IGE attributes the growin...The induction generator effect(IGE)and the openloop modal proximity(OLMP)are two different reasons why subsynchronous oscillations(SSOs)in a series-compensated power system(SCPS)may occur.The IGE attributes the growing SSOs to negative resistance,while the OLMP explains the SSO mechanism from the standpoint of modal conditions.In this paper,we investigate the connections between the IGE and the OLMP through equivalent RLC circuit and open-loop modal analysis.Our investigation is conducted for two types of seriescompensated power systems where either a synchronous generator or a DFIG is connected at the sending end.The investigation reveals the conditions,in which the IGE and the OLMP may jointly cause the growing SSOs,i.e.,both the IGE and the OLMP can explain why the growing SSOs occur.Furthermore,the investigation indicates that the IGE and the OLMP may be totally irrelevant and lead to growing SSOs separately.This implies that it is possible that in a SCPS,the growing SSOs are only due to the IGE,and the OLMP is non-existent,and vice versa.Hence,when the growing SSOs occurs in a SCPS,examination based on both the IGE and the OLMP should be carefully conducted in order to find if the oscillatory instability is due to the IGE,or the OLMP,or both of them.展开更多
A pot experiment has been carried out under controlled conditions to study the possibility of applying the technique of in vivo staining for acid phosphatase activity on the roots of mycorrhizal plants and arbuscular ...A pot experiment has been carried out under controlled conditions to study the possibility of applying the technique of in vivo staining for acid phosphatase activity on the roots of mycorrhizal plants and arbuscular mycorrhizal hyphae. The pots had 5 compartments. The central root compartment was separated from the two adjacent hyphal compartments using nylon nets of 30 μm mesh, and the two hyphal compartments were separated from the two outermost compartments with 0.45 μm membranes. Red clover was grown in the root compartment and was either inoculated with the arbuscular mycorrhizal fungus (AMF) Glomus mosseae or uninoculated. Sodium phytate was applied to all compartments. The results show that AMF can increase acid phosphatase activity of clover roots. The plant roots acquired deep red 'mycorrhizal prints'. The external hyphae also had obvious 'hyphal prints' on the test papers, indicating the ability of mycorrhizal hyphae to release acid phosphatase.展开更多
To make methane a suitable energy carrier and transport less costly,it is an urgent and challenging task for us to convert methane to liquid under mild conditions efficiently.In this study,we explored partial methane ...To make methane a suitable energy carrier and transport less costly,it is an urgent and challenging task for us to convert methane to liquid under mild conditions efficiently.In this study,we explored partial methane oxidation to methanol by density functional theory(DFT)calculations using a hybrid functional(HSE06)with van der Waals(vdW)interactions.The stabilities of different active sites over SSZ-13 and SAPO-34,two CHA type zeolites,are thoroughly investigated by ab initio molecular dynamics(AIMD)simulations and ab initio thermodynamics analyses.Four possible active sites,namely[CuOHCu]2+,[Cu(OH)2Cu]2+,[CuOCu]2+and[CuOH]+,are identified stable.Methane-to-methanol reaction mechanisms are further studied upon these most stable active sites,among which[CuOCu]2+and[CuOH]+are proved to be reactive.The migration of species among zeolite pores are also discussed,which accounts for the activity on[CuOH]+sites.This concept may represent a more complete picture of catalytic reactions over zeolites in general.展开更多
Fe-based solid catalysts in promoting Fenton reaction to generate ·OH radical has drawn much attention,and interestingly,FeOCl was reported to have superior activity compared with the traditional Fe2 O3 catalysts...Fe-based solid catalysts in promoting Fenton reaction to generate ·OH radical has drawn much attention,and interestingly,FeOCl was reported to have superior activity compared with the traditional Fe2 O3 catalysts.However,the mechanism of Fenton reaction on FeOCl and the origin of high activity remain unclear.Herein,by virtue of DFT+ U calculations,the H2 O2 decomposition and conversion mechanism on FeOCl(100)surface were systematically investigated.It is found that on clean FeOCl(100)surface,the exposed[Fe^3+-Fe^3+]sites can hardly break O-O bond of H2 O2 into OH groups,but instead H2 O2 tends to dehydrogenate by the surface lattice O,resulting in a series of side reactions and final conversion into O2,while the left H atoms gradually saturate the surface lattice O and reduce Fe^3+ into Fe^2+.On fully H-covered FeOCl(100),H2O2 can efficiently dissociate at[Fe^2+-Fe^2+]sites into two OH,but OH binds with Fe^2+ so strongly that it cannot desorb as OH radical as easily as that on Fe^3+.Interestingly,FeOCl(100)tends to be partially protonated in the real acid solution,which,along with H2 O2 dehydrogenation,results in the formation of active unit [Fe^2+-Fe^3+].On[Fe^2+-Fe^3+]unit,H2 O2 can easily break its O-O bond and OH at Fe3+ can desorb as OH radical,while the other OH at Fe^2+ couples with the surface H into H2O and finish the catalytic cycle.By comparison,Fe2 O3(012)cannot provide enough [Fe^2+-Fe^3+] active units due to the relative difficulty in H2 O2 dehydrogenation,which accounts for its inferior catalytic efficiency for Fenton reaction.展开更多
Different plants have physiological responses under Al stress,but there is no systematic study to examine physiological responses of herbaceous plants under Al stress.The aim of this study is to investigate the effect...Different plants have physiological responses under Al stress,but there is no systematic study to examine physiological responses of herbaceous plants under Al stress.The aim of this study is to investigate the effect of Al on physiological characteristics of four herbaceous plants,which distributed in red soil area in South China,and to analyze the differences in physiological responses to Al stress between the four herbaceous plants.Four herbaceous plants(Pharbitis nil,Cassia occidentlis,Echinochloa colonum and Aeschynomene indica)were used,and the seed germi-nation percentage,the contents of chlorophyll,proline,and malondialdehyde(MDA),membrane permeability(MP),soluble sugar,and activities of peroxides(POD)and cata-lase(CAT)in leaves under five Al^(3+)treatments(0,80,400,2000,and 10000 mg/L)were assayed with the sand culture method.The results showed remarkable effects of Al^(3+)on physiological characteristics of these four herbaceous plants.The seeds of all the four species could not germinate at 10000 mg/L,and the growth of all plants were retarded under the 2000 mg/L Al^(3+)treatment.Compared with the control,2000 mg/L Al^(3+)significantly(P<0.05)reduced the con-tents of chlorophyll a and chlorophyll a+b,and increased the contents of MDA and MP.The content of proline in-creased very significantly(P<0.01)and activities of POD and CAT were depressed.The contents of MDA and MP in leaves of P.nil and A.indica decreased,and the activities of POD and CAT in leaves of the two plants increased under 80 mg/L and 400 mg/L.However,the changes in C.occidentlis leaves were opposite to those of the above two plants.The changes in leaves of E.colonum were similar to those of P.nil and A.indica at 80 mg/L,but were opposite to those at 400 mg/L Al^(3+).It is suggested that plants with higher ac-tivities of POD and CAT,more contents of chlorophyll and proline,and lower contents of MDA and MP consequently improve the tolerance to Al stress under low and middle Al treatments.展开更多
文摘Dear Editor, Lithium-ion(Li-ion) battery has become a promising source to supply and absorb energy/power for many energy-transportation applications. However, Li-ion battery capacity would inevitably degrade over time, making its related ageing prediction necessary.
文摘Single-atom catalysts have been applied in many processes recently.The difference of their kinetic behavior compared to the traditional heterogeneous catalysts has not been extensively discussed yet.Herein a complete catalytic cycle of CH4 combustion assuming to be confined at isolated single sites of the Co3O4(110)surface is computationally compared with that on multi sites.The macroscopic kinetic behaviors of CH4 combustion on Co3O4(110)is systematically and quantitatively compared between those on the single site and multi sites utilizing kinetic Monte Carlo simulations upon the energetic information from the PBE+U calculation and statistic mechanics.The key factors governing the kinetics of CH4 combustion are disclosed for both the catalytic cycles respectively following the single-site and multi-site mechanisms.It is found that cooperation of multi active sites can promote the activity of complete CH4 combustions substantially in comparison to separated single-site catalyst whereas the confinement of active sites could regulate the selectivity of CH4 oxidation.The quantitative understanding of catalytic mechanism paves the way to improve the activity and selectivity for CH4 oxidation.
文摘In comparison to studies investigating the roles of 5-HT1, 5-HT2 and 5-HT3 receptors in aggressive behaviour there is a dearth of material examining the function of 5-HT4 receptors in this behaviour. In view of this, the current study examined the effects of the 5-HT4 receptor partial agonist RS 67333 and antagonist RS 39604 in murine agonistic behaviour. RS 67333 failed to produce any significant changes in the offensive. Significant variation in the frequency of evade behaviour was detected but this occurred between treatment groups rather than with controls. Interestingly, both the frequency and duration of stretched attend behaviour were increased by RS 67333 0.1 mg/kg, a result indicative of increased risk assessment. The administration of RS 39604 (0.01 - 1 mg/kg) produced significant variation in the fre-quency and duration of following, and aggressive grooming. Frozen crouch behaviour was also increased significantly at 0.1 mg/kg. It is concluded that since the 5-HT4 receptor ligands employed in this study produced very few significant behavioural effects across the treatment groups, 5-HT4 receptors do not play a role in the modulation of murine aggressive behaviour.
文摘In a system consisting of an electron and a highly-charged ion,interaction with the radiation field is important.This means radiation-damping effects must be accurately taken into account.The present work discusses the radiation-damping effect in the processes of photoionization,radiative recombination,and electron scattering.
文摘Cloud computing has created a paradigm shift that affects the way in which business applications are developed. Many business organizations use cloud infrastructures as platforms on which to deploy business applications. Increasing numbers of vendors are supplying the cloud marketplace with a wide range of cloud products. Different vendors offer cloud products in different formats. The cost structures for consuming cloud products can be complex. Finding a suitable set of cloud products that meets an application’s requirements and budget can be a challenging task. In this paper, an ontology-based resource mapping mechanism is proposed. Domain-specific ontologies are used to specify high-level application’s requirements. These are then translated into high-level infrastructure ontologies which then can be mapped onto low-level descriptions of cloud resources. Cost ontologies are proposed for cloud resources. An exemplar media transcoding and delivery service is studied in order to illustrate how high-level requirements can be modeled and mapped onto cloud resources within a budget constraint. The proposed ontologies provide an application-centric mechanism for specifying cloud requirements which can then be used for searching for suitable resources in a multi-provider cloud environment.
文摘This paper discusses and critically reviews the causes and consequences of global standardization and local adaptation of marketing strategies.The scope of the literature review is in the fields of international marketing,international trade,and corporate strategic management.It also aims to emphasize finding gaps after reading the literature.Even though the studies’scope is extensive,this paper limits the reach:firstly,it introduces the standardization and local adaptation,discusses the advantages and disadvantages of both by researchers.At the same time,untangle the relationship between international marketing strategy and marketing mix.Secondly,it is divided into macro and micro to collate and analyze the leading factors affecting international strategy,so that the cross-market fit of global marketing tactic can be realised.Finally,focus on the KPI.The indicators of financial return were selected as the review from the factors representing the intuitive development level of the company.The goal was to concentrate on the mutual feedback and adjustment between the standardization/adaptation and performance of multinational companies.Among them,the diversities between developed and emerging markets are interspersed in each link.As this difference is a trend that scholars have begun to notice in recent years.Although many existed bibliographies are revolved around particular multinational companies or regions to assessment,this paper will focus on the impact of practical research article review and evaluation.It would not involve specific corporate and country.
基金supported in part by the National Natural Science Foundation of China under Grant 52077144by the Fundamental Research Funds for the Central Universities(YJ201654).
文摘The induction generator effect(IGE)and the openloop modal proximity(OLMP)are two different reasons why subsynchronous oscillations(SSOs)in a series-compensated power system(SCPS)may occur.The IGE attributes the growing SSOs to negative resistance,while the OLMP explains the SSO mechanism from the standpoint of modal conditions.In this paper,we investigate the connections between the IGE and the OLMP through equivalent RLC circuit and open-loop modal analysis.Our investigation is conducted for two types of seriescompensated power systems where either a synchronous generator or a DFIG is connected at the sending end.The investigation reveals the conditions,in which the IGE and the OLMP may jointly cause the growing SSOs,i.e.,both the IGE and the OLMP can explain why the growing SSOs occur.Furthermore,the investigation indicates that the IGE and the OLMP may be totally irrelevant and lead to growing SSOs separately.This implies that it is possible that in a SCPS,the growing SSOs are only due to the IGE,and the OLMP is non-existent,and vice versa.Hence,when the growing SSOs occurs in a SCPS,examination based on both the IGE and the OLMP should be carefully conducted in order to find if the oscillatory instability is due to the IGE,or the OLMP,or both of them.
文摘A pot experiment has been carried out under controlled conditions to study the possibility of applying the technique of in vivo staining for acid phosphatase activity on the roots of mycorrhizal plants and arbuscular mycorrhizal hyphae. The pots had 5 compartments. The central root compartment was separated from the two adjacent hyphal compartments using nylon nets of 30 μm mesh, and the two hyphal compartments were separated from the two outermost compartments with 0.45 μm membranes. Red clover was grown in the root compartment and was either inoculated with the arbuscular mycorrhizal fungus (AMF) Glomus mosseae or uninoculated. Sodium phytate was applied to all compartments. The results show that AMF can increase acid phosphatase activity of clover roots. The plant roots acquired deep red 'mycorrhizal prints'. The external hyphae also had obvious 'hyphal prints' on the test papers, indicating the ability of mycorrhizal hyphae to release acid phosphatase.
基金supported by the Queen’s University of Belfast and Chinese Scholarship Council for a Joint Scholarship。
文摘To make methane a suitable energy carrier and transport less costly,it is an urgent and challenging task for us to convert methane to liquid under mild conditions efficiently.In this study,we explored partial methane oxidation to methanol by density functional theory(DFT)calculations using a hybrid functional(HSE06)with van der Waals(vdW)interactions.The stabilities of different active sites over SSZ-13 and SAPO-34,two CHA type zeolites,are thoroughly investigated by ab initio molecular dynamics(AIMD)simulations and ab initio thermodynamics analyses.Four possible active sites,namely[CuOHCu]2+,[Cu(OH)2Cu]2+,[CuOCu]2+and[CuOH]+,are identified stable.Methane-to-methanol reaction mechanisms are further studied upon these most stable active sites,among which[CuOCu]2+and[CuOH]+are proved to be reactive.The migration of species among zeolite pores are also discussed,which accounts for the activity on[CuOH]+sites.This concept may represent a more complete picture of catalytic reactions over zeolites in general.
基金financially supported by the National Natural Science Foundation of China(Nos.21622305 and21333003)the Young Elite Scientist Sponsorship Program by China Association for Science and Technology(No.YESS20150131)+1 种基金"Shu Guang"Project supported by Shanghai Municipal Education Commission and Shanghai Education Development Foundation(No.17SG30)the Fundamental Research Funds for the Central Universities(No.WJ1616007)
文摘Fe-based solid catalysts in promoting Fenton reaction to generate ·OH radical has drawn much attention,and interestingly,FeOCl was reported to have superior activity compared with the traditional Fe2 O3 catalysts.However,the mechanism of Fenton reaction on FeOCl and the origin of high activity remain unclear.Herein,by virtue of DFT+ U calculations,the H2 O2 decomposition and conversion mechanism on FeOCl(100)surface were systematically investigated.It is found that on clean FeOCl(100)surface,the exposed[Fe^3+-Fe^3+]sites can hardly break O-O bond of H2 O2 into OH groups,but instead H2 O2 tends to dehydrogenate by the surface lattice O,resulting in a series of side reactions and final conversion into O2,while the left H atoms gradually saturate the surface lattice O and reduce Fe^3+ into Fe^2+.On fully H-covered FeOCl(100),H2O2 can efficiently dissociate at[Fe^2+-Fe^2+]sites into two OH,but OH binds with Fe^2+ so strongly that it cannot desorb as OH radical as easily as that on Fe^3+.Interestingly,FeOCl(100)tends to be partially protonated in the real acid solution,which,along with H2 O2 dehydrogenation,results in the formation of active unit [Fe^2+-Fe^3+].On[Fe^2+-Fe^3+]unit,H2 O2 can easily break its O-O bond and OH at Fe3+ can desorb as OH radical,while the other OH at Fe^2+ couples with the surface H into H2O and finish the catalytic cycle.By comparison,Fe2 O3(012)cannot provide enough [Fe^2+-Fe^3+] active units due to the relative difficulty in H2 O2 dehydrogenation,which accounts for its inferior catalytic efficiency for Fenton reaction.
基金supported by the National Natural Science Foundation of China (No.30540056)the Natural Science Foundation of Zhejiang Province (No.303461,504135).
文摘Different plants have physiological responses under Al stress,but there is no systematic study to examine physiological responses of herbaceous plants under Al stress.The aim of this study is to investigate the effect of Al on physiological characteristics of four herbaceous plants,which distributed in red soil area in South China,and to analyze the differences in physiological responses to Al stress between the four herbaceous plants.Four herbaceous plants(Pharbitis nil,Cassia occidentlis,Echinochloa colonum and Aeschynomene indica)were used,and the seed germi-nation percentage,the contents of chlorophyll,proline,and malondialdehyde(MDA),membrane permeability(MP),soluble sugar,and activities of peroxides(POD)and cata-lase(CAT)in leaves under five Al^(3+)treatments(0,80,400,2000,and 10000 mg/L)were assayed with the sand culture method.The results showed remarkable effects of Al^(3+)on physiological characteristics of these four herbaceous plants.The seeds of all the four species could not germinate at 10000 mg/L,and the growth of all plants were retarded under the 2000 mg/L Al^(3+)treatment.Compared with the control,2000 mg/L Al^(3+)significantly(P<0.05)reduced the con-tents of chlorophyll a and chlorophyll a+b,and increased the contents of MDA and MP.The content of proline in-creased very significantly(P<0.01)and activities of POD and CAT were depressed.The contents of MDA and MP in leaves of P.nil and A.indica decreased,and the activities of POD and CAT in leaves of the two plants increased under 80 mg/L and 400 mg/L.However,the changes in C.occidentlis leaves were opposite to those of the above two plants.The changes in leaves of E.colonum were similar to those of P.nil and A.indica at 80 mg/L,but were opposite to those at 400 mg/L Al^(3+).It is suggested that plants with higher ac-tivities of POD and CAT,more contents of chlorophyll and proline,and lower contents of MDA and MP consequently improve the tolerance to Al stress under low and middle Al treatments.