Exploring efficient catalyst is critical for the application of persulfate-based advanced oxidation processes(AOPs)for environment remediation.Herein,perovskite CoTiO_(3)was demonstrated an efficient catalyst for pero...Exploring efficient catalyst is critical for the application of persulfate-based advanced oxidation processes(AOPs)for environment remediation.Herein,perovskite CoTiO_(3)was demonstrated an efficient catalyst for peroxymonosulfate(PMS)activation,which shows superior performance compared with single metal oxide system and homogenous systems:It removes 98.2%of hydroxychloroquine(HCQ,drugs for effective treatment of COVID-19)within 20 min at low dose of PMS(0.5 mmol/L),showing high tolerance to the environmental p H range(3.5–10.6)and significant versatility for various refractory organics.Combined with the material characterization and DFT calculations,it is found Co–O–Ti bond in CoTiO_(3)serves as an electron mediator to facilitate the rapid redox cycles of Co^(2+)/Co^(3+)during activation process,thus maintaining the high catalytic activity.Further mechanism exploration showed that fast regeneration of Co^(2+)ensures the production of high concentration of SO_(4)·-and·OH,thus securing the rapid degradation of HCQ.Moreover,a designed CoTiO_(3)-CNT-PVDF membrane reactor can effectively remove refractory pollutant via practically feasible filter-through mode,which delivers a highest removal efficiency and longest operation duration compared with previous developed membrane-based AOPs.The corresponding mechanism revealed in this work can serve as guidelines for the design of advanced heterogenous catalysts and membrane reactors for AOPs.展开更多
To formulate fluids with flowback water,produced water directly to improve the utilization rate of recycling and reduce the adsorption damage of slick water to reservoirs,a high salt tolerance and low adsorption drag ...To formulate fluids with flowback water,produced water directly to improve the utilization rate of recycling and reduce the adsorption damage of slick water to reservoirs,a high salt tolerance and low adsorption drag reducer was designed and prepared by introducing polar cation fragments to enhance the non-covalent interactions between the chains.The drag reducer was characterized by IR and NMR.Friction resistance and viscosity tests were conducted to evaluate its salt resistance property.Static adsorption and dynamic adsorption retention tests were carried out to evaluate the damage of this reducer to shale reservoirs.The introduction of cation units into the molecular structure can weak the shielding effect of metal cations to some extent,so the drag reducer can keep a stable molecular structure and good resistant reducing performance under high salinity.The enhancement of non-covalent interaction between chains decreased the free polarity sites,further reduced the possibility of hydrogen bonding between drag reducer molecules and shale.In high salinity condition,both the adsorption capacity of the drag reducer on the shale surface and the average damage rate to the core permeability are low.Compared with the conventional salt-tolerant system,the overall liquid cost was reduced by 17%and the production per well increased by 44%.The application of this slick water system has achieved remarkable results.展开更多
In order to obtain Pleurotus ferulae with high temperature tolerance, conidiophores of wild type strain ACK were implanted with nitrogen ions in energy of 5 -15 keV and dose of 1.5×10^15 - 1.5 × 10^16 cm^-2,...In order to obtain Pleurotus ferulae with high temperature tolerance, conidiophores of wild type strain ACK were implanted with nitrogen ions in energy of 5 -15 keV and dose of 1.5×10^15 - 1.5 × 10^16 cm^-2, and a mutant CGMCC1763 was isolated subsequently through thermotolerant screening method. It was found that during riper period the surface layer mycelium of the mutant in mushroom bag wasn＇t aging neither grew tegument even above 30℃. The mycelium endurable temperature of the mutant was increased by 5℃ compared to that of the wild type strain. The fruiting bodies growth temperature of the mutant was 18 -22℃ in daytime and 8 -14℃ at night. The highest growth temperature of fruiting bodies of the mutant was increased about 7℃ w.r.t, that of original strain. Through three generations investigations, it was found that the mutant CGMCC1763 was stable with high temperature tolerance.展开更多
We propose and demonstrate a synchronously pumped mode-locked Tm-doped fiber（TDF） laser without any extra mode-locking elements. Pumped by a 1.56 μm pulse fiber laser, the TDF laser generates 1.17 ps pulses with a ...We propose and demonstrate a synchronously pumped mode-locked Tm-doped fiber（TDF） laser without any extra mode-locking elements. Pumped by a 1.56 μm pulse fiber laser, the TDF laser generates 1.17 ps pulses with a spectral width of 9.7 nm and a repetition rate of 9.33 MHz. The emission wavelength is tunable along with the cavity length detuning in a wide range of 3 mm. The high detuning toleration is beneficial to achieve high temperature and vibration stability in all-fiber configuration lasers.展开更多
During wireless charging,misalignments commonly occur in the transmission between the transmitting and receiving pads,including misalignments in the forward,backward,lateral and vertical directions.Unavoidable misalig...During wireless charging,misalignments commonly occur in the transmission between the transmitting and receiving pads,including misalignments in the forward,backward,lateral and vertical directions.Unavoidable misalignments can result in changes in system parameters,thus affecting charging performance.A novel diagonally crossed solenoid magnetic coupler(DCSMC)is developed as a solution.The DCSMC integrated into a wireless power transfer(WPT)system with a hybrid topology enables superior misalignment tolerance in the X,Y,Zand XYdiagonal directionswhile maintaining load-independent voltage output characteristics.A simplified parameter design method is developed to optimize the misalignment tolerance performance of a hybrid WPT system in multiple directions.Finally,a hardware prototype of a WPT system is constructed with an operating frequency of 200kHz and a power of 200W.The experimental results showthat the hybrid WPT system,operating under loads from 40Ωto 80Ω,can tolerate misalignments of±90mm(40.9%)in both the Xand Yaxes,maintaining as small as a 5%fluctuation in output voltage.In addition,the WPT system can handle a maximum vertical displacement of+40mm along the Z-axis and XY-diagonal misalignments of±40mm(12.8%).展开更多
Organic solar cells(OSCs)have attracted significant attention as next-generation photovoltaics due to their unique advantages such as mechanical flexibility,lightweight,and solution processability.While state-of-the-a...Organic solar cells(OSCs)have attracted significant attention as next-generation photovoltaics due to their unique advantages such as mechanical flexibility,lightweight,and solution processability.While state-of-the-art power conversion efficiencies(PCEs)exceeding 20%are achieved in inert atmospheres,ambient processing remains a critical challenge for scalable production.Particularly detrimental is moisture penetration into the active layer,which induces a cascade of deleterious effects including trap state formation,charge carrier mobility imbalance,enhanced nonradiative recombination,and disruption of crystalline ordering,ultimately leading to severe device performance losses.Addressing these challenges necessitates strategic molecular engineering to enhance intrinsic moisture resistance by incorporating functional side chains into donor and acceptor materials and using small-molecule additives that suppress water condensation,stabilize morphology,and maintain efficient charge transport.This review systematically summarizes recent progress in the field of humiditytolerant ambient-processed OSCs.Donor:acceptor systems are categorized according to the reported processing humidity levels,including unspecified conditions,low humidity(RH<40%),moderate humidity(RH=40−70%),and high humidity(RH>70%).Encouragingly,even under 90%RH,some systems achieve the PCEs over 18%,demonstrating significant progress toward airprocessed OSCs with high humidity tolerance.These advancements highlight the great promise of molecular engineering strategies to enable the scalable fabrication of high-performance OSCs under ambient conditions with enhanced humidity tolerance.展开更多
The conjugation of SUMO （small ubiquitin-like modifier） to protein substrates is a reversible process （SUMOylation/deSUMOylation） that regulates plant devel- opment and stress responses. The essential metal copper...The conjugation of SUMO （small ubiquitin-like modifier） to protein substrates is a reversible process （SUMOylation/deSUMOylation） that regulates plant devel- opment and stress responses. The essential metal copper （Cu） is required for normal plant growth, but excess amounts are toxic. The SUMO E3 ligase, SIZI, and SIZ1- mediated SUMOylation function in plant tolerance to excess Cu. It is unknown whether deSUMOylation also contributes to Cu tolerance in plants. Here, we report that OTSI, a protease that cleaves SUMO from its substrate proteins, participates in Cu tolerance in Arabidopsis thaliana （Arabi- dopsis）. OTS1 loss-of-function mutants （otsl-2 and otsl-3） displayed increased sensitivity to excess Cu. Redox homeostasis and the balance between SUMOylation and deSUMOylation were disrupted in the otsl-3 mutant under excess Cu conditions, The otsl-3 mutant accumulated higher levels of Cu in both shoots and roots compared to wild type. Specific Cu-related metal transporter genes were upregu- lated due to the loss-of-function of OTS% which might explain the high Cu levels in otsl-3. These results suggest that the SUMOylation/deSUMOylation machinery is acti- vated in response to excess Cu, and modulates Cu homeostasis and tolerance by regulating both Cu uptake and detoxification. Together, our findings provide insight into the biological function and regulatory role of SUMOylation/deSUMOylation in plant tolerance to Cu.展开更多
Color filters in different surroundings inherently suffer from angular sensitivity,which hinders their practical applications.Here,we present an angle-insensitive plasmonic filter that can produce different color resp...Color filters in different surroundings inherently suffer from angular sensitivity,which hinders their practical applications.Here,we present an angle-insensitive plasmonic filter that can produce different color responses to different surrounding environments.The color filters are based on a two-dimensional periodically and randomly distributed silver nanodisk array on a silica substrate.The proposed plasmonic color filters not only produce bright colors by altering the diameter of the Ag nanodisk,but also achieve continuous color palettes by changing the surrounding environment.Due to the weak coupling between the metallic nanodisks,the plasmonic color filters can enable good incident angle-insensitive properties(up to 30°).The strategy presented here could exhibit robust and promising applicability in anti-counterfeiting and imaging technologies.展开更多
With radical global climate change and global warming, high temperature stress has become one of major factors exerting a major Influence on crop production, In the cotton （Gossyplum hirsutum L.）-growlng areas of Ch...With radical global climate change and global warming, high temperature stress has become one of major factors exerting a major Influence on crop production, In the cotton （Gossyplum hirsutum L.）-growlng areas of China, especially in the Yangtze River valley, unexpected periodic episodes of extreme heat stress usually occur In July and August, the peak time of cotton flowering and boll loading, resulting In lower boll set and lint yield. Breeding programs for screening high temperature-tolerant cotton germplasm and cultlvars are urgent In order to stabilize yield in the current and future warmer weather conditions. In the present study, 14 cotton cultivars were quantified for in vitro pollen germination and pollen tube growth in response to temperatures ranging from 10 to 50 ℃ at 5 ℃ intervals. Different cotton genotypes varied In their in vitro pollen germination and pollen tube length responses to the different temperatures. Maximum pollen germination and pollen tube length ranged from 25.2% to 56.2% and from 414 to 682 pro, respectively. The average cardinal temperatures （Tmin,, Topt, and Tmax） also varied among the 14 cultivars and were 11.8, 27.3, and 42.7 ℃ for pollen germination and 11.8, 27.8, and 44.1 ℃ for maximum pollen tube length. Variations In boll retention and boll numbers per plant in field experiments were found for the 14 cotton cultivars and the boll retention and boll retained per plant on 20 August varied considerably In different years according to weather conditions. Boll retention on 20 August was highly correlated with maximum pollen germination （R^2 = 0.84） and pollen tube length （R^2=0.64）. A screening method based on principle component analysis of the combination of pollen characterlatics In an in vitro experiment and boll retention testing In the field environment was used In the present study and, as a result, the 14 cotton cultlvars could be classified as tolerant, moderately tolerant, moderately susceptible and susceptible to high temperature.展开更多
Failures are normal rather than exceptional in the cloud computing environments. To improve system avai- lability, replicating the popular data to multiple suitable locations is an advisable choice, as users can acces...Failures are normal rather than exceptional in the cloud computing environments. To improve system avai- lability, replicating the popular data to multiple suitable locations is an advisable choice, as users can access the data from a nearby site. This is, however, not the case for replicas which must have a fixed number of copies on several locations. How to decide a reasonable number and right locations for replicas has become a challenge in the cloud computing. In this paper, a dynamic data replication strategy is put forward with a brief survey of replication strategy suitable for distributed computing environments. It includes： 1） analyzing and modeling the relationship between system availability and the number of replicas; 2） evaluating and identifying the popular data and triggering a replication operation when the popularity data passes a dynamic threshold; 3） calculating a suitable number of copies to meet a reasonable system byte effective rate requirement and placing replicas among data nodes in a balanced way; 4） designing the dynamic data replication algorithm in a cloud. Experimental results demonstrate the efficiency and effectiveness of the improved system brought by the proposed strategy in a cloud.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52100084 and 52170155)Shenzhen Natural Science Fund(the stable support plan program,No.GXWD20231129152058003)。
文摘Exploring efficient catalyst is critical for the application of persulfate-based advanced oxidation processes(AOPs)for environment remediation.Herein,perovskite CoTiO_(3)was demonstrated an efficient catalyst for peroxymonosulfate(PMS)activation,which shows superior performance compared with single metal oxide system and homogenous systems:It removes 98.2%of hydroxychloroquine(HCQ,drugs for effective treatment of COVID-19)within 20 min at low dose of PMS(0.5 mmol/L),showing high tolerance to the environmental p H range(3.5–10.6)and significant versatility for various refractory organics.Combined with the material characterization and DFT calculations,it is found Co–O–Ti bond in CoTiO_(3)serves as an electron mediator to facilitate the rapid redox cycles of Co^(2+)/Co^(3+)during activation process,thus maintaining the high catalytic activity.Further mechanism exploration showed that fast regeneration of Co^(2+)ensures the production of high concentration of SO_(4)·-and·OH,thus securing the rapid degradation of HCQ.Moreover,a designed CoTiO_(3)-CNT-PVDF membrane reactor can effectively remove refractory pollutant via practically feasible filter-through mode,which delivers a highest removal efficiency and longest operation duration compared with previous developed membrane-based AOPs.The corresponding mechanism revealed in this work can serve as guidelines for the design of advanced heterogenous catalysts and membrane reactors for AOPs.
基金Supported by the China National Science and Technology Major Project(2017ZX05023003)National Science Fund for Distinguished Young Scholars(51525404)
文摘To formulate fluids with flowback water,produced water directly to improve the utilization rate of recycling and reduce the adsorption damage of slick water to reservoirs,a high salt tolerance and low adsorption drag reducer was designed and prepared by introducing polar cation fragments to enhance the non-covalent interactions between the chains.The drag reducer was characterized by IR and NMR.Friction resistance and viscosity tests were conducted to evaluate its salt resistance property.Static adsorption and dynamic adsorption retention tests were carried out to evaluate the damage of this reducer to shale reservoirs.The introduction of cation units into the molecular structure can weak the shielding effect of metal cations to some extent,so the drag reducer can keep a stable molecular structure and good resistant reducing performance under high salinity.The enhancement of non-covalent interaction between chains decreased the free polarity sites,further reduced the possibility of hydrogen bonding between drag reducer molecules and shale.In high salinity condition,both the adsorption capacity of the drag reducer on the shale surface and the average damage rate to the core permeability are low.Compared with the conventional salt-tolerant system,the overall liquid cost was reduced by 17%and the production per well increased by 44%.The application of this slick water system has achieved remarkable results.
基金the National Development and Reform Committee of China(No.[2004]2077)
文摘In order to obtain Pleurotus ferulae with high temperature tolerance, conidiophores of wild type strain ACK were implanted with nitrogen ions in energy of 5 -15 keV and dose of 1.5×10^15 - 1.5 × 10^16 cm^-2, and a mutant CGMCC1763 was isolated subsequently through thermotolerant screening method. It was found that during riper period the surface layer mycelium of the mutant in mushroom bag wasn＇t aging neither grew tegument even above 30℃. The mycelium endurable temperature of the mutant was increased by 5℃ compared to that of the wild type strain. The fruiting bodies growth temperature of the mutant was 18 -22℃ in daytime and 8 -14℃ at night. The highest growth temperature of fruiting bodies of the mutant was increased about 7℃ w.r.t, that of original strain. Through three generations investigations, it was found that the mutant CGMCC1763 was stable with high temperature tolerance.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61675188 and 61875052the Open Fund of Key Laboratory Pulse Power Laser Technology of China under Grant No SKL2016KF03
文摘We propose and demonstrate a synchronously pumped mode-locked Tm-doped fiber（TDF） laser without any extra mode-locking elements. Pumped by a 1.56 μm pulse fiber laser, the TDF laser generates 1.17 ps pulses with a spectral width of 9.7 nm and a repetition rate of 9.33 MHz. The emission wavelength is tunable along with the cavity length detuning in a wide range of 3 mm. The high detuning toleration is beneficial to achieve high temperature and vibration stability in all-fiber configuration lasers.
基金Supported by the Guangdong Basic and Applied Basic Research Foundation(2023A1515240033)the Basic and Applied Basic Research Foundation of Guangzhou(2024A04J6540)the Natural Science Foundation for Distinguished Young Scholars of Guangdong Province(2022B1515020002).
文摘During wireless charging,misalignments commonly occur in the transmission between the transmitting and receiving pads,including misalignments in the forward,backward,lateral and vertical directions.Unavoidable misalignments can result in changes in system parameters,thus affecting charging performance.A novel diagonally crossed solenoid magnetic coupler(DCSMC)is developed as a solution.The DCSMC integrated into a wireless power transfer(WPT)system with a hybrid topology enables superior misalignment tolerance in the X,Y,Zand XYdiagonal directionswhile maintaining load-independent voltage output characteristics.A simplified parameter design method is developed to optimize the misalignment tolerance performance of a hybrid WPT system in multiple directions.Finally,a hardware prototype of a WPT system is constructed with an operating frequency of 200kHz and a power of 200W.The experimental results showthat the hybrid WPT system,operating under loads from 40Ωto 80Ω,can tolerate misalignments of±90mm(40.9%)in both the Xand Yaxes,maintaining as small as a 5%fluctuation in output voltage.In addition,the WPT system can handle a maximum vertical displacement of+40mm along the Z-axis and XY-diagonal misalignments of±40mm(12.8%).
基金financial support of the National Natural Science Foundation of China(22179040)the Basic and Applied Basic Research Major Program of Guangdong Province(2019B030302007)the Guangdong Basic and Applied Basic Research Foundation(2024A1515012693).
文摘Organic solar cells(OSCs)have attracted significant attention as next-generation photovoltaics due to their unique advantages such as mechanical flexibility,lightweight,and solution processability.While state-of-the-art power conversion efficiencies(PCEs)exceeding 20%are achieved in inert atmospheres,ambient processing remains a critical challenge for scalable production.Particularly detrimental is moisture penetration into the active layer,which induces a cascade of deleterious effects including trap state formation,charge carrier mobility imbalance,enhanced nonradiative recombination,and disruption of crystalline ordering,ultimately leading to severe device performance losses.Addressing these challenges necessitates strategic molecular engineering to enhance intrinsic moisture resistance by incorporating functional side chains into donor and acceptor materials and using small-molecule additives that suppress water condensation,stabilize morphology,and maintain efficient charge transport.This review systematically summarizes recent progress in the field of humiditytolerant ambient-processed OSCs.Donor:acceptor systems are categorized according to the reported processing humidity levels,including unspecified conditions,low humidity(RH<40%),moderate humidity(RH=40−70%),and high humidity(RH>70%).Encouragingly,even under 90%RH,some systems achieve the PCEs over 18%,demonstrating significant progress toward airprocessed OSCs with high humidity tolerance.These advancements highlight the great promise of molecular engineering strategies to enable the scalable fabrication of high-performance OSCs under ambient conditions with enhanced humidity tolerance.
基金supported by the National Transgenic Major Project of China (2016ZX08009-003-002 to H.L.)the National Natural Science Foundation of China (31600201 to H.Z+1 种基金 31470342 and 31670235 to H.L.)the National Basic Research Program of China (2015CB150100 to H.L)
文摘The conjugation of SUMO （small ubiquitin-like modifier） to protein substrates is a reversible process （SUMOylation/deSUMOylation） that regulates plant devel- opment and stress responses. The essential metal copper （Cu） is required for normal plant growth, but excess amounts are toxic. The SUMO E3 ligase, SIZI, and SIZ1- mediated SUMOylation function in plant tolerance to excess Cu. It is unknown whether deSUMOylation also contributes to Cu tolerance in plants. Here, we report that OTSI, a protease that cleaves SUMO from its substrate proteins, participates in Cu tolerance in Arabidopsis thaliana （Arabi- dopsis）. OTS1 loss-of-function mutants （otsl-2 and otsl-3） displayed increased sensitivity to excess Cu. Redox homeostasis and the balance between SUMOylation and deSUMOylation were disrupted in the otsl-3 mutant under excess Cu conditions, The otsl-3 mutant accumulated higher levels of Cu in both shoots and roots compared to wild type. Specific Cu-related metal transporter genes were upregu- lated due to the loss-of-function of OTS% which might explain the high Cu levels in otsl-3. These results suggest that the SUMOylation/deSUMOylation machinery is acti- vated in response to excess Cu, and modulates Cu homeostasis and tolerance by regulating both Cu uptake and detoxification. Together, our findings provide insight into the biological function and regulatory role of SUMOylation/deSUMOylation in plant tolerance to Cu.
基金Project supported by the National Key Research and Development Program of China(Grant No.2022YFB2804602)Shanghai Pujiang Program(Grant No.21PJD048).
文摘Color filters in different surroundings inherently suffer from angular sensitivity,which hinders their practical applications.Here,we present an angle-insensitive plasmonic filter that can produce different color responses to different surrounding environments.The color filters are based on a two-dimensional periodically and randomly distributed silver nanodisk array on a silica substrate.The proposed plasmonic color filters not only produce bright colors by altering the diameter of the Ag nanodisk,but also achieve continuous color palettes by changing the surrounding environment.Due to the weak coupling between the metallic nanodisks,the plasmonic color filters can enable good incident angle-insensitive properties(up to 30°).The strategy presented here could exhibit robust and promising applicability in anti-counterfeiting and imaging technologies.
基金Supported by the State Key Basic Research and Development Plan of China(2004CB117306)
文摘With radical global climate change and global warming, high temperature stress has become one of major factors exerting a major Influence on crop production, In the cotton （Gossyplum hirsutum L.）-growlng areas of China, especially in the Yangtze River valley, unexpected periodic episodes of extreme heat stress usually occur In July and August, the peak time of cotton flowering and boll loading, resulting In lower boll set and lint yield. Breeding programs for screening high temperature-tolerant cotton germplasm and cultlvars are urgent In order to stabilize yield in the current and future warmer weather conditions. In the present study, 14 cotton cultivars were quantified for in vitro pollen germination and pollen tube growth in response to temperatures ranging from 10 to 50 ℃ at 5 ℃ intervals. Different cotton genotypes varied In their in vitro pollen germination and pollen tube length responses to the different temperatures. Maximum pollen germination and pollen tube length ranged from 25.2% to 56.2% and from 414 to 682 pro, respectively. The average cardinal temperatures （Tmin,, Topt, and Tmax） also varied among the 14 cultivars and were 11.8, 27.3, and 42.7 ℃ for pollen germination and 11.8, 27.8, and 44.1 ℃ for maximum pollen tube length. Variations In boll retention and boll numbers per plant in field experiments were found for the 14 cotton cultivars and the boll retention and boll retained per plant on 20 August varied considerably In different years according to weather conditions. Boll retention on 20 August was highly correlated with maximum pollen germination （R^2 = 0.84） and pollen tube length （R^2=0.64）. A screening method based on principle component analysis of the combination of pollen characterlatics In an in vitro experiment and boll retention testing In the field environment was used In the present study and, as a result, the 14 cotton cultlvars could be classified as tolerant, moderately tolerant, moderately susceptible and susceptible to high temperature.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 61070162, 71071028 and 70931001the Specialized Research Fund for the Doctoral Program of Higher Education of China under Grant Nos. 20110042110024 and 20100042110025the Fundamental Research Funds for the Central Universities of China under Grant Nos. N100604012, N090504003 and N090504006
文摘Failures are normal rather than exceptional in the cloud computing environments. To improve system avai- lability, replicating the popular data to multiple suitable locations is an advisable choice, as users can access the data from a nearby site. This is, however, not the case for replicas which must have a fixed number of copies on several locations. How to decide a reasonable number and right locations for replicas has become a challenge in the cloud computing. In this paper, a dynamic data replication strategy is put forward with a brief survey of replication strategy suitable for distributed computing environments. It includes： 1） analyzing and modeling the relationship between system availability and the number of replicas; 2） evaluating and identifying the popular data and triggering a replication operation when the popularity data passes a dynamic threshold; 3） calculating a suitable number of copies to meet a reasonable system byte effective rate requirement and placing replicas among data nodes in a balanced way; 4） designing the dynamic data replication algorithm in a cloud. Experimental results demonstrate the efficiency and effectiveness of the improved system brought by the proposed strategy in a cloud.
