Herein, we report the design and synthesis of three new D-A type metal-free carbazole based dyes(S_(1-3))as effective co-sensitizers for dye-sensitized solar cell(DSSC) sensitized with Ru(Ⅱ) complex(NCSU-10).In this ...Herein, we report the design and synthesis of three new D-A type metal-free carbazole based dyes(S_(1-3))as effective co-sensitizers for dye-sensitized solar cell(DSSC) sensitized with Ru(Ⅱ) complex(NCSU-10).In this new design, the electron rich carbazole unit was attached to three different electron withdrawing/anchoring species, viz. 4-amino benzoic acid, sulfanilic acid and barbituric acid. The dyes were characterized by spectral, photophysical and electrochemical analysis. Their optical and electrochemical parameters along with molecular geometries, optimized from DFT have been employed to apprehend the effect of the structures of these co-sensitizers on the photovoltaic performances. Further, S_(1-3) dyes were co-sensitized along with a well-known NCSU-10 dye in order to broaden the spectral response of the co-sensitized devices and hence improve the efficiency. The photovoltaic performance studies indicated that, the device fabricated using S_1 dye as co-sensitizer with 0.2 mM of NCSU-10 exhibited improved PCE of 9.55% with J_(SC) of 22.85 mA cm^(-2), V_(OC) of 0.672 V and FF of 62.2%, whereas the DSSC fabricated with dye NCSU-10(0.2 mM) alone displayed PCE of 8.25% with J_(SC) of 20.41 mA cm^(-2), V_(OC) of 0.667 V and FF of 60.6%. Furthermore, electronic excitations simulated using time-dependent DFT, were in good agreement with the experimentally obtained results of the co-sensitizers, indicating that the exchange-correlation function and basis set utilized for predicting the spectra of the co-sensitizers are quite appropriate for the calculations. In conclusion, the results showed the potential of simple organic co-sensitizers in the development of efficient DSSCs.展开更多
Socialism with Chinese characteristics is a great cause without experience for reference. Under the general theme of adhering to and developing socialism with Chinese characteristics,the basic issues of socialism with...Socialism with Chinese characteristics is a great cause without experience for reference. Under the general theme of adhering to and developing socialism with Chinese characteristics,the basic issues of socialism with Chinese characteristics are specifically composed of three aspects: the ruling construction of the Communist Party of China,the construction of socialism with Chinese characteristics and the development of human society. In the process of realizing the great leap of the Chinese nation to stand up,become rich,and become strong,the Chinese Communists,mainly represented by Mao Zedong,Deng Xiaoping,Jiang Zemin,Hu Jintao and Xi Jinping,have relayed to explore the basic issues of socialism with Chinese characteristics over the past 70 years,and constantly deepen their understanding of the laws governing the construction of the ruling party,the laws of socialist construction,and the laws of the development of human society.展开更多
In the framework of vigorous promotion of low-carbon power system growth as well as economic globalization,multi-resource penetration in active distribution networks has been advancing fiercely.In particular,distribut...In the framework of vigorous promotion of low-carbon power system growth as well as economic globalization,multi-resource penetration in active distribution networks has been advancing fiercely.In particular,distributed generation(DG)based on renewable energy is critical for active distribution network operation enhancement.To comprehensively analyze the accessing impact of DG in distribution networks from various parts,this paper establishes an optimal DG location and sizing planning model based on active power losses,voltage profile,pollution emissions,and the economics of DG costs as well as meteorological conditions.Subsequently,multiobjective particle swarm optimization(MOPSO)is applied to obtain the optimal Pareto front.Besides,for the sake of avoiding the influence of the subjective setting of the weight coefficient,the decisionmethod based on amodified ideal point is applied to execute a Pareto front decision.Finally,simulation tests based on IEEE33 and IEEE69 nodes are designed.The experimental results show thatMOPSO can achieve wider and more uniformPareto front distribution.In the IEEE33 node test system,power loss,and voltage deviation decreased by 52.23%,and 38.89%,respectively,while taking the economy into account.In the IEEE69 test system,the three indexes decreased by 19.67%,and 58.96%,respectively.展开更多
Lipotoxicity is a pivotal factor that initiates and exacerbates liver injury and is involved in the development of metabolic-associated fatty liver disease(MAFLD).However,there are few reported lipotoxicity inhibitors...Lipotoxicity is a pivotal factor that initiates and exacerbates liver injury and is involved in the development of metabolic-associated fatty liver disease(MAFLD).However,there are few reported lipotoxicity inhibitors.Here,we identified a natural anti-lipotoxicity candidate,HN-001,from the marine fungus Aspergillus sp.C1.HN-001 dose-and time-dependently reversed palmitic acid(PA)-induced hepatocyte death.This protection was associated with IRE-1a-mediated XBP-1 splicing inhibition,which resulted in suppression of XBP-1s nuclear translocation and transcriptional regulation.Knockdown of XBP-1s attenuated lipotoxicity,but no additional ameliorative effect of HN-001 on lipotoxicity was observed in XBP-1s knockdown hepatocytes.Notably,the ER stress and lipotoxicity amelioration was associated with PLA2.Both HN-001 and the PLA2 inhibitor MAFP inhibited PLA2 activity,reduced lysophosphatidylcholine(LPC)level,subsequently ameliorated lipotoxicity.In contrast,overexpression of PLA2 caused exacerbation of lipotoxicity and weakened the anti-lipotoxic effects of HN-001.Additionally,HN-001 treatment suppressed the downstream pro-apoptotic JNK pathway.In vivo,chronic administration of HN-001(i.p.)in mice alleviated all manifestations of MAFLD,including hepatic steatosis,liver injury,inflammation,and fibrogenesis.These effects were correlated with PLA2/IRE-1a/XBP-1s axis and JNK signaling suppression.These data indicate that HN-001 has therapeutic potential for MAFLD because it suppresses lipotoxicity,and provide a natural structural basis for developing anti-MAFLD candidates.展开更多
The fast dynamic properties of the surface of metallic glasses(MGs) play a critical role in determining their potential applications. However, due to the significant difference in thermal history between atomic simula...The fast dynamic properties of the surface of metallic glasses(MGs) play a critical role in determining their potential applications. However, due to the significant difference in thermal history between atomic simulation models and laboratory-made samples, the atomic-scale behaviors of the fast surface dynamics of MGs in experiments remain uncertain. Herein, we prepared model MG films with notable variations in thermal stability using a recently developed efficient annealing protocol, and investigated their atomic-scale dynamics systematically. We found that the dynamics of surface atoms remain invariant, whereas the difference in dynamical heterogeneity between surface and interior regions increases with the improvement of thermal stability. This can be associated with the more pronounced correlation between atomic activation energy spectra and depth from the surface in samples with higher thermal stability. In addition, dynamic anisotropy appears for surface atoms, and their transverse dynamics are faster than normal components, which can also be interpreted by activation energy spectra. Our results reveal the presence of strong liquid-like atomic dynamics confined to the surface of laboratory-made MGs, illuminating the underlying mechanisms for surface engineering design, such as cold joining by ultrasonic vibrations and superlattice growth.展开更多
With the rapid development of nuclear power in China, the disposal of high-level radioactive waste(HLW) has become an important issue for nuclear safety and environmental protection. Deep geological disposal is intern...With the rapid development of nuclear power in China, the disposal of high-level radioactive waste(HLW) has become an important issue for nuclear safety and environmental protection. Deep geological disposal is internationally accepted as a feasible and safe way to dispose of HLW, and underground research laboratories(URLs) play an important and multi-faceted role in the development of HLW repositories. This paper introduces the overall planning and the latest progress for China's URL. On the basis of the proposed strategy to build an area-specific URL in combination with a comprehensive evaluation of the site selection results obtained during the last 33 years, the Xinchang site in the Beishan area,located in Gansu Province of northwestern China, has been selected as the final site for China's first URL built in granite. In the process of characterizing the Xinchang URL site, a series of investigations,including borehole drilling,geological mapping, geophysical surveying,hydraulic testing and in situ stress measurements, has been conducted. The investigation results indicate that the geological,hydrogeological, engineering geological and geochemical conditions of the Xinchang site are very suitable for URL construction. Meanwhile, to validate and develop construction technologies for the Beishan URL, the Beishan exploration tunnel(BET), which is a 50-m-deep facility in the Jiujing sub-area, has been constructed and several in situ tests, such as drill-and-blast tests, characterization of the excavation damaged zone(EDZ), and long-term deformation monitoring of surrounding rocks, have been performed in the BET. The methodologies and technologies established in the BET will serve for URL construction.According to the achievements of the characterization of the URL site, a preliminary design of the URL with a maximum depth of 560 m is proposed and necessary in situ tests in the URL are planned.展开更多
Isolated pillars in underground mines are subjected to uniaxial stress,and the load bearing cross-section of pillars is commonly rectangularly shaped.In addition,the uniaxial compression test(UCT)is widely used for de...Isolated pillars in underground mines are subjected to uniaxial stress,and the load bearing cross-section of pillars is commonly rectangularly shaped.In addition,the uniaxial compression test(UCT)is widely used for determining the basic mechanical properties of rocks and revealing the mechanism of isolated pillar disasters under unidimensional stress.The shape effects of rock mechanical properties under uniaxial compression are mainly quantitatively reflected in the specific shape ratios of rocks.Therefore,it is necessary to study the detailed shape ratio effects on the mechanical properties of rectangular prism rock specimens and isolated pillars under uniaxial compressive stress.In this study,granite,marble and sandstone rectangular prism specimens with various height to width ratios(r)and width to thickness ratios(u)were prepared and tested.The study results show that r and u have a great influence on the bearing ability of rocks,and thin or high rocks have lower uniaxial compressive strength.Reducing the level of r can enhance the u effect on the strength of rocks,and increasing the level of u can enhance the r effect on the strength of rocks.The lateral strain on the thickness side of the rock specimen is larger than that on the width side,which implies that crack growth occurs easily on the thickness side.Considering r and u,a novel strength prediction model of isolated pillars was proposed based on the testing results,and the prediction model was used for the safety assessment of 179 isolated pillars in the Xianglu Mountain Tungsten Mine.展开更多
Ultra-long,single crystal,Eu-doped α-Si3N4 nanowires were prepared by a simple approach involving nitriding Eu-doped cryomilled nanocrystalline Si powder in NH3 flow at 1350℃ for 4 h.Phases,chemical composition and ...Ultra-long,single crystal,Eu-doped α-Si3N4 nanowires were prepared by a simple approach involving nitriding Eu-doped cryomilled nanocrystalline Si powder in NH3 flow at 1350℃ for 4 h.Phases,chemical composition and microcosmic feature were tested by X-ray diffraction(XRD),field emission scanning electron microscopy(FESEM),transmission electron mi-展开更多
East China(23.6°–38.4°N,113.6°–122.9°E)is the largest developed region in China.Based on CO2 products retrieved from the Greenhouse Gases Observing Satellite(GOSAT),the spatial and temporal distr...East China(23.6°–38.4°N,113.6°–122.9°E)is the largest developed region in China.Based on CO2 products retrieved from the Greenhouse Gases Observing Satellite(GOSAT),the spatial and temporal distributions of CO2 mixing ratios in East China during 2014–17 are discussed,and the retrieved CO2 from AIRS(Atmospheric Infrared Sounder)and OCO-2(Orbiting Carbon Observatory-2),as well as WLG(Waliguan)background station observations,are compared with those of GOSAT.The annual CO2 retrieved from GOSAT in East China ranged from 398.96±0.24 ppm in 2014 to 407.39±0.20 ppm in 2017,with a growth rate of 2.82±0.15 ppm yr^−1,which were higher than in other regions of China.The seasonal cycle presented a maximum in spring and a minimum in summer or autumn.Higher values were mainly concentrated in the coastal areas of Zhejiang Province,and lower values were concentrated in Jiangxi and the north of Fujian Province.CO2 observed in Fujian and parts of Jiangxi increased by less than 1.0 ppm during 2014–15,but enhanced significantly by more than 5.0 ppm during 2015–16,perhaps influenced by local emissions and global impacts.We calculated year-to-year CO2 enhancements in the Yangtze River Delta region during 2014–17 that were relatively low and stable,due to the region’s carbon emissions control and reduction policies.The annual and seasonal amplitudes of CO2 retrieved from AIRS were lower than those from GOSAT in East China,probably owing to the CO2 retrieved from AIRS better reflecting the characteristics of the mid-troposphere,while GOSAT is more representative of near-surface CO2.The spatial and temporal distribution characteristics of CO2 retrieved from OCO-2 were close to those from GOSAT in East China.展开更多
Tumorous stem mustard is well known for its swollen stem from which pickled“Fuling Mustard”is made.The molecular mechanisms governing the formation of the modified swollen stems are still poorly understood.This pape...Tumorous stem mustard is well known for its swollen stem from which pickled“Fuling Mustard”is made.The molecular mechanisms governing the formation of the modified swollen stems are still poorly understood.This paper aims to identify candidate genes involved in the developmental regulation of the swollen stems.We sought to map previously published transcriptome datasets for Brassica juncea,including those derived from swollen stems at four different developmental stages and a mutant variety without swollen stems.Using pairwise comparisons of the five datasets,we identified 31368 differentially expressed genes(DEGs).A total of 55 DEGs related to plant hormone signal transduction and 259 continuously up-or downregulated transcription factors were identified during stem development using Gene Ontology(GO)analysis.Quantitative real-time PCR(qRT-PCR)results showed that the expressions of 12 important candidate DEGs were consistent with RNA-seq results.Our study provided digital gene expression profiling and a dynamic view of the swollen stem development process.Furthermore,we identified candidate genes for further studies on mechanisms of modified stem development in non-model species.展开更多
To solve the problem of deformation and cracking of ballastless track slab under temperature load,a composite oxide and a series of heat-reflective coating samples were prepared.At the microscopic level,the elemental ...To solve the problem of deformation and cracking of ballastless track slab under temperature load,a composite oxide and a series of heat-reflective coating samples were prepared.At the microscopic level,the elemental composition and optical properties of the materials prepared were analyzed by Fourier transform infrared spectroscopy and ultraviolet-visible spectroscopy,and the feasibility of Ce/Si/Ti oxide as functional fillers for heat-reflective coatings of track slabs was demonstrated.At the macro level,by designing and assembling an indoor sunlight simulation test device,the surface and internal temperatures of the coated and uncoated concrete specimens were analyzed and studied,and the macroscopic cooling effect of the coatings was evaluated.Also,to study the engineering application effect of the track slab thermal insulation reflective coating,COMSOL was used to build a 3D calculation model of the heat transfer deformation of the ballastless track slab structure.The research results showed that:Ce/Si/Ti oxide has strong reflectivity and can reflect 95%of infrared light;it has good ultraviolet(UV)shielding ability and can absorb more than 65%of the UV light.The TiO2 coating can reduce the temperature of the concrete surface by 6–11℃and that of the inside of the concrete by 10–14℃;the cooling effect decreases evenly with the increase of air temperature.The Ce/Si/Ti oxide coating can reduce the surface temperature of the concrete by 16℃and that of the inside of the concrete by 15℃.In addition,the cooling effect is basically not affected by the air temperature,and it changes non-linearly with the increase of the Ce/Si/Ti oxide content.Numerical calculation shows that the heat reflective coating can reduce the surface temperature and internal temperature difference of the track slab by 11.54–21.31℃,and the vertical displacement of the track slab can be reduced by about 35%–70%.Considering the cooling effect,the adhesion strength,and the engineering application effect of the coating,the optimal doping amount of Ce/Si/Ti oxide is 40%,and that coating is the most suitable for use as a ballastless track heat reflective coating.展开更多
Fundamental understandings on the dynamics of charge carriers and excitonic quasiparticles in semiconductors are of central importance for both many-body physics and promising optoelectronic and photonic applications....Fundamental understandings on the dynamics of charge carriers and excitonic quasiparticles in semiconductors are of central importance for both many-body physics and promising optoelectronic and photonic applications.Here,we investigated the carrier dynamics and many-body interactions in two-dimensional(2D)transition metal dichalcogenides(TMDs),using monolayer WS2 as an example,by employing femtosecond broadband pump-probe spectroscopy.Three time regimes for the exciton energy renormalization are unambiguously revealed with a distinct red-blue-red shift upon above-bandgap optical excitations.We attribute the dominant physical process in the three typical regimes to free carrier screening effect,Coulombic exciton-exciton interactions and Auger photocarrier generation,respectively,which show distinct dependence on the optical excitation wavelength,pump fluences and/or lattice temperature.An intrinsic exciton radiative lifetime of about 1.2 picoseconds(ps)in monolayer WS2 is unraveled at low temperature,and surprisingly the efficient Auger nonradiative decay of both bright and dark excitons puts the system in a nonequilibrium state at the nanosecond timescale.In addition,the dynamics of trions at low temperature is observed to be significantly different from that of excitons,e.g.,a long radiative lifetime of^108.7 ps at low excitation densities and the evolution of trion energy as a function of delay times.Our findings elucidate the dynamics of excitonic quasiparticles and the intricate many-body physics in 2D semiconductors,underpinning the future development of photonics,valleytronics and optoelectronics based on 2D semiconductors.展开更多
Emerging technologies in the field of environmental remediation are becoming increasingly significant owing to the increasing demand for eliminating significant amounts of pollution in water,soil,and air.We designed a...Emerging technologies in the field of environmental remediation are becoming increasingly significant owing to the increasing demand for eliminating significant amounts of pollution in water,soil,and air.We designed and synthesized MoS 2/Fe 2 O 3 heterojunction nanocomposites(NCs)as multifunctional materials that are easily separated and reused.The trace detection performance of the prepared sample was examined using bisphenol A(BPA)as the probe molecule,with limits of detection as low as 10−9 M;this detection limit is the lowest among all reported semiconductor substrates.BPA was subjected to rapid photocatalytic degradation by MoS_(2)/Fe_(2)O_(3) NCs under ultraviolet irradiation.The highly recyclable MoS_(2)/Fe_(2)O_(3) NCs exhibited photo-Fenton catalytic activity for BPA and good detection ability when reused as a surface-enhanced Raman scattering(SERS)substrate after catalysis.The SERS and photocatalysis mechanisms were proposed while considering the effects of the Z-scheme charge-transfer paths,three-dimensional flower-like structures,and dipole–dipole coupling.Moreover,the prepared MoS_(2)/Fe_(2)O_(3) NCs were successfully applied in the detection of BPA in real lake water and milk samples.Herein,we present insights into the development of MoS_(2)/Fe_(2)O_(3) materials,which can be used as multifunctional materials in chemical sensors and in photocatalytic wastewater treatments for the removal of recalcitrant organic pollutants.展开更多
In 2018-2019,two types of rocket-triggered lightning tests,that is,striking to ground and distribution line,were conducted in Guangdong,China.The main focus of this paper is to compare the waveform parameters of the r...In 2018-2019,two types of rocket-triggered lightning tests,that is,striking to ground and distribution line,were conducted in Guangdong,China.The main focus of this paper is to compare the waveform parameters of the return strokes(RS)from the two tests.For current,the 10%-90%risetime of RS from lightning striking to distribution line is 2.4 times higher than that striking to ground,and the differences in the other parameters are small.For close magnetic field,the RS from lightning striking to distribution line have a lower peak(30%lower after considering the peak current)and a larger risetime and half-peak width time;besides,it is necessary to divide the front edge of the close magnetic field waveform into two parts:leader(BL)and return stroke(BRS).For close electric field,the close RS electric field peak(ERS)was less sensitive to distance than the leader electric field peak(EL).For far electric field,the differences in waveform parameters of RS from the two tests were not significant,but after considering the peak current,the normalised initial electric field peak(EP)of RS from lightning striking to distribution line was 14%lower than that striking to ground.展开更多
The double-threshold method has been widely used in ultrasonic flow measurement to determine time-of-flight(TOF)due to its low cost and ease of implementation.Performance of this method is negatively affected by the c...The double-threshold method has been widely used in ultrasonic flow measurement to determine time-of-flight(TOF)due to its low cost and ease of implementation.Performance of this method is negatively affected by the cycle-skip phenomenon which occurs frequently under inconstant working conditions,especially varied fluid temperature.This paper proposes a method to suppress the phenomenon to facilitate reliable determination of TOF in ultrasonic flow measurement.First,the double-threshold method is used to generate a feature point to segment the signal.Second,based on the correlation coefficient and signal power,judgement factors of individual signal periods are calculated to determine signal onset.Finally,a valid zero crossing which has a constant lag from the onset is selected to determine the TOF.Thus,the cycle-skip phenomenon is suppressed.Two additional modifications are proposed to eliminate the influence of varied signal frequency and low sampling rate.The proposed method was validated by an experiment based on an ultrasonic water flow sensor.Results showed that the frequently appearing cycle-skip phenomenon can be successfully suppressed by the proposed method.展开更多
Polyetheretherketone(PEEK)has been used as an implant material because it has similar mechani-cal properties to natural bone.However,inferior osseointegration and bioinertness hamper the clinical application of PEEK.I...Polyetheretherketone(PEEK)has been used as an implant material because it has similar mechani-cal properties to natural bone.However,inferior osseointegration and bioinertness hamper the clinical application of PEEK.In this study,the surfaces of sulfonated three-dimensional(3D)PEEK porous structures were loaded with different concentrations of strontium ranelate,a compound commonly used in the treatment or prevention of osteoporosis by promoting bone formation and inhibiting bone resorption.Field-emission scanning electron microscopy was used to characterize the topography of the structures,elemental carbon,oxygen and strontium contents were mea-sured by X-ray photoelectron spectroscopy,and surface zeta potentials and water-contact angle were also measured.The results indicated that strontium ranelate was successfully loaded onto the 3D porous structures.In vitro cellular results showed that strontium ranelate-treated sulfonated PEEK(SP-SR)strengthened the adhesion of MC3T3-E1 cells.The activity of alkaline phosphatase,collagen secretion and extracellular matrix mineralization deposition of MC3T3-E1 cells were also improved on the surface of SP-SR.These results indicate that SP-SR could serve a new implant candidate for surgical treatment.展开更多
Residual water-induced decomposition is one of the dominant reasons for the decay of power conversion efficiency (PCE) in perovskite solar cells (Pero-SCs). To solve this problem, we introduce traces amount of sodium ...Residual water-induced decomposition is one of the dominant reasons for the decay of power conversion efficiency (PCE) in perovskite solar cells (Pero-SCs). To solve this problem, we introduce traces amount of sodium hyaluronate (SH) into the perovskite active layer to reduce the remaining water during the preparation of perovskite films. Unlike the traditionally adopted passive protection of perovskite from exterior water by low surface energy coatings, this study provides active control of the interior water by the addition of a water adsorbent into the perovskite films. The encapsulated Pero-SCs with SH retain approximately 70% of their initial PCE in 4000 h, while those without SH retain 32% of their initial PCE in 1000 h under the dark and ambient atmosphere. The unencapsulated Pero-SCs with SH stored in N2 atmosphere maintain over 94% of the initial PCE in 3000 h at room temperature away from light and remain over 88% of the initial PCE in 2000 h even the devices are heated to 70 °C. It has been proven that the improved stability is mainly due to the well-controlled residual water in perovskite films. Concomitantly, the PCE of p-i-n solar cells based on (FAPbI3)0.85(MAPbBr3)0.15 is improved from 19.34% to 21.54%.展开更多
The adsorption properties of Cu 2+ -loaded montmorillonite clays (MMT-Cu) for Escherichia coli K 88 as a function of time,bacteria concentrations,pH,ionic strength and temperature were investigated.The results showed ...The adsorption properties of Cu 2+ -loaded montmorillonite clays (MMT-Cu) for Escherichia coli K 88 as a function of time,bacteria concentrations,pH,ionic strength and temperature were investigated.The results showed that the bacteria adsorption onto MMT-Cu surface reached equilibrium after 90 min.The percentages of E.coli K 88 adsorbed onto the surfaces of MMT-Cu and montmorillonite clays (MMT) at equilibrium were 88.9% and 56.5%,respectively.Scanning electron microscopy revealed that a lot of E.coli K 88 adhered to the surface of MMT-Cu.The zeta potential of MMT-Cu was relatively high as compared to that of MMT.The adsorptive ability of MMT-Cu for E.coli K 88 was higher than that of MMT (P < 0.05).Moreover,pH,ionic strength and temperature produced a strong influence on the extent of E.coli K 88 adsorption to surface of MMT-Cu and MMT.The mechanism of adsorption of E.coli onto MMT-Cu may involve electrostatic attraction and physiochemical properties of bacterial cell walls and minerals surfaces.展开更多
基金Department of Textile Engineering, Chemistry and Science at North Carolina State University for the financial support
文摘Herein, we report the design and synthesis of three new D-A type metal-free carbazole based dyes(S_(1-3))as effective co-sensitizers for dye-sensitized solar cell(DSSC) sensitized with Ru(Ⅱ) complex(NCSU-10).In this new design, the electron rich carbazole unit was attached to three different electron withdrawing/anchoring species, viz. 4-amino benzoic acid, sulfanilic acid and barbituric acid. The dyes were characterized by spectral, photophysical and electrochemical analysis. Their optical and electrochemical parameters along with molecular geometries, optimized from DFT have been employed to apprehend the effect of the structures of these co-sensitizers on the photovoltaic performances. Further, S_(1-3) dyes were co-sensitized along with a well-known NCSU-10 dye in order to broaden the spectral response of the co-sensitized devices and hence improve the efficiency. The photovoltaic performance studies indicated that, the device fabricated using S_1 dye as co-sensitizer with 0.2 mM of NCSU-10 exhibited improved PCE of 9.55% with J_(SC) of 22.85 mA cm^(-2), V_(OC) of 0.672 V and FF of 62.2%, whereas the DSSC fabricated with dye NCSU-10(0.2 mM) alone displayed PCE of 8.25% with J_(SC) of 20.41 mA cm^(-2), V_(OC) of 0.667 V and FF of 60.6%. Furthermore, electronic excitations simulated using time-dependent DFT, were in good agreement with the experimentally obtained results of the co-sensitizers, indicating that the exchange-correlation function and basis set utilized for predicting the spectra of the co-sensitizers are quite appropriate for the calculations. In conclusion, the results showed the potential of simple organic co-sensitizers in the development of efficient DSSCs.
文摘Socialism with Chinese characteristics is a great cause without experience for reference. Under the general theme of adhering to and developing socialism with Chinese characteristics,the basic issues of socialism with Chinese characteristics are specifically composed of three aspects: the ruling construction of the Communist Party of China,the construction of socialism with Chinese characteristics and the development of human society. In the process of realizing the great leap of the Chinese nation to stand up,become rich,and become strong,the Chinese Communists,mainly represented by Mao Zedong,Deng Xiaoping,Jiang Zemin,Hu Jintao and Xi Jinping,have relayed to explore the basic issues of socialism with Chinese characteristics over the past 70 years,and constantly deepen their understanding of the laws governing the construction of the ruling party,the laws of socialist construction,and the laws of the development of human society.
基金The authors gratefully acknowledge the support of the Enhancement Strategy of Multi-Type Energy Integration of Active Distribution Network(YNKJXM20220113).
文摘In the framework of vigorous promotion of low-carbon power system growth as well as economic globalization,multi-resource penetration in active distribution networks has been advancing fiercely.In particular,distributed generation(DG)based on renewable energy is critical for active distribution network operation enhancement.To comprehensively analyze the accessing impact of DG in distribution networks from various parts,this paper establishes an optimal DG location and sizing planning model based on active power losses,voltage profile,pollution emissions,and the economics of DG costs as well as meteorological conditions.Subsequently,multiobjective particle swarm optimization(MOPSO)is applied to obtain the optimal Pareto front.Besides,for the sake of avoiding the influence of the subjective setting of the weight coefficient,the decisionmethod based on amodified ideal point is applied to execute a Pareto front decision.Finally,simulation tests based on IEEE33 and IEEE69 nodes are designed.The experimental results show thatMOPSO can achieve wider and more uniformPareto front distribution.In the IEEE33 node test system,power loss,and voltage deviation decreased by 52.23%,and 38.89%,respectively,while taking the economy into account.In the IEEE69 test system,the three indexes decreased by 19.67%,and 58.96%,respectively.
基金This study was supported by National Natural Science Foundation of China(82260674 to Yong Rao,82160653 to Ling Huang)Fundamental Research Funds for Hainan University(KYQD(ZR)-21114 to Yong Rao,KYQD(ZR)-21089 to Ling Huang,China)+2 种基金Hainan Provincial Natural Science Foundation of China(822MS054 to Yong Rao)Natural Science Foundation of Guangdong Province(2021A1515010488 to Yong Rao,China)Central Public-interest Scientific Institution Basal Research Fund for CATAS-ITBB(1630052022016,1630052019011,China).
文摘Lipotoxicity is a pivotal factor that initiates and exacerbates liver injury and is involved in the development of metabolic-associated fatty liver disease(MAFLD).However,there are few reported lipotoxicity inhibitors.Here,we identified a natural anti-lipotoxicity candidate,HN-001,from the marine fungus Aspergillus sp.C1.HN-001 dose-and time-dependently reversed palmitic acid(PA)-induced hepatocyte death.This protection was associated with IRE-1a-mediated XBP-1 splicing inhibition,which resulted in suppression of XBP-1s nuclear translocation and transcriptional regulation.Knockdown of XBP-1s attenuated lipotoxicity,but no additional ameliorative effect of HN-001 on lipotoxicity was observed in XBP-1s knockdown hepatocytes.Notably,the ER stress and lipotoxicity amelioration was associated with PLA2.Both HN-001 and the PLA2 inhibitor MAFP inhibited PLA2 activity,reduced lysophosphatidylcholine(LPC)level,subsequently ameliorated lipotoxicity.In contrast,overexpression of PLA2 caused exacerbation of lipotoxicity and weakened the anti-lipotoxic effects of HN-001.Additionally,HN-001 treatment suppressed the downstream pro-apoptotic JNK pathway.In vivo,chronic administration of HN-001(i.p.)in mice alleviated all manifestations of MAFLD,including hepatic steatosis,liver injury,inflammation,and fibrogenesis.These effects were correlated with PLA2/IRE-1a/XBP-1s axis and JNK signaling suppression.These data indicate that HN-001 has therapeutic potential for MAFLD because it suppresses lipotoxicity,and provide a natural structural basis for developing anti-MAFLD candidates.
基金sponsored by the National Natural Science Foundation of China (Grant No. 52101201)supported by the National Natural Science Foundation of China (Grant No.T2325004)+2 种基金sponsored by the National Natural Science Foundation of China(Grant No. 51801046)the Natural Science Foundation of Chongqing,China (Grant No. cstc2021jcyj-msxm X0369)the Science Fund for Scientific and Technological Innovation Team of Shaanxi Province (Grant No. 2021TD-14)。
文摘The fast dynamic properties of the surface of metallic glasses(MGs) play a critical role in determining their potential applications. However, due to the significant difference in thermal history between atomic simulation models and laboratory-made samples, the atomic-scale behaviors of the fast surface dynamics of MGs in experiments remain uncertain. Herein, we prepared model MG films with notable variations in thermal stability using a recently developed efficient annealing protocol, and investigated their atomic-scale dynamics systematically. We found that the dynamics of surface atoms remain invariant, whereas the difference in dynamical heterogeneity between surface and interior regions increases with the improvement of thermal stability. This can be associated with the more pronounced correlation between atomic activation energy spectra and depth from the surface in samples with higher thermal stability. In addition, dynamic anisotropy appears for surface atoms, and their transverse dynamics are faster than normal components, which can also be interpreted by activation energy spectra. Our results reveal the presence of strong liquid-like atomic dynamics confined to the surface of laboratory-made MGs, illuminating the underlying mechanisms for surface engineering design, such as cold joining by ultrasonic vibrations and superlattice growth.
基金support from the China Atomic Energy Authority (CAEA) for China's URL Development Program and the Geological Disposal ProgramThe International Atomic Energy Agency is specially thanked for its support for China's geological disposal program through its Technical Cooperation Projects
文摘With the rapid development of nuclear power in China, the disposal of high-level radioactive waste(HLW) has become an important issue for nuclear safety and environmental protection. Deep geological disposal is internationally accepted as a feasible and safe way to dispose of HLW, and underground research laboratories(URLs) play an important and multi-faceted role in the development of HLW repositories. This paper introduces the overall planning and the latest progress for China's URL. On the basis of the proposed strategy to build an area-specific URL in combination with a comprehensive evaluation of the site selection results obtained during the last 33 years, the Xinchang site in the Beishan area,located in Gansu Province of northwestern China, has been selected as the final site for China's first URL built in granite. In the process of characterizing the Xinchang URL site, a series of investigations,including borehole drilling,geological mapping, geophysical surveying,hydraulic testing and in situ stress measurements, has been conducted. The investigation results indicate that the geological,hydrogeological, engineering geological and geochemical conditions of the Xinchang site are very suitable for URL construction. Meanwhile, to validate and develop construction technologies for the Beishan URL, the Beishan exploration tunnel(BET), which is a 50-m-deep facility in the Jiujing sub-area, has been constructed and several in situ tests, such as drill-and-blast tests, characterization of the excavation damaged zone(EDZ), and long-term deformation monitoring of surrounding rocks, have been performed in the BET. The methodologies and technologies established in the BET will serve for URL construction.According to the achievements of the characterization of the URL site, a preliminary design of the URL with a maximum depth of 560 m is proposed and necessary in situ tests in the URL are planned.
基金funded by the National Natural Science Foundation of China(Nos.51774326,42177164,41807259,and41702350)Hunan Young Talent(No.2021RC3007)+2 种基金the open fund of Mining Disaster Prevention and Control Ministry Key Laboratory at Shandong University of Science and Technology(No.MDPC201917)the Fundamental Research Funds for the Central Universities of Central South University(No.2019zzts668)the Innovation-Driven Project of Central South University(No.2020CX040)。
文摘Isolated pillars in underground mines are subjected to uniaxial stress,and the load bearing cross-section of pillars is commonly rectangularly shaped.In addition,the uniaxial compression test(UCT)is widely used for determining the basic mechanical properties of rocks and revealing the mechanism of isolated pillar disasters under unidimensional stress.The shape effects of rock mechanical properties under uniaxial compression are mainly quantitatively reflected in the specific shape ratios of rocks.Therefore,it is necessary to study the detailed shape ratio effects on the mechanical properties of rectangular prism rock specimens and isolated pillars under uniaxial compressive stress.In this study,granite,marble and sandstone rectangular prism specimens with various height to width ratios(r)and width to thickness ratios(u)were prepared and tested.The study results show that r and u have a great influence on the bearing ability of rocks,and thin or high rocks have lower uniaxial compressive strength.Reducing the level of r can enhance the u effect on the strength of rocks,and increasing the level of u can enhance the r effect on the strength of rocks.The lateral strain on the thickness side of the rock specimen is larger than that on the width side,which implies that crack growth occurs easily on the thickness side.Considering r and u,a novel strength prediction model of isolated pillars was proposed based on the testing results,and the prediction model was used for the safety assessment of 179 isolated pillars in the Xianglu Mountain Tungsten Mine.
文摘Ultra-long,single crystal,Eu-doped α-Si3N4 nanowires were prepared by a simple approach involving nitriding Eu-doped cryomilled nanocrystalline Si powder in NH3 flow at 1350℃ for 4 h.Phases,chemical composition and microcosmic feature were tested by X-ray diffraction(XRD),field emission scanning electron microscopy(FESEM),transmission electron mi-
基金The authors thank the staff of WLG station in Qinghai Province for their data sampling and maintenance of the observation system.We are also grateful to NASA for providing the CO2 products retrieved from AIRS,OCO-2 and JAXA for providing the CO2 product retrieved from GOSAT.This research was supported by the China Meteorological Administration Climate Change Special Project(No.CCSF202035)the Jiangxi Meteorological Science and Technology Project(201805,201905).
文摘East China(23.6°–38.4°N,113.6°–122.9°E)is the largest developed region in China.Based on CO2 products retrieved from the Greenhouse Gases Observing Satellite(GOSAT),the spatial and temporal distributions of CO2 mixing ratios in East China during 2014–17 are discussed,and the retrieved CO2 from AIRS(Atmospheric Infrared Sounder)and OCO-2(Orbiting Carbon Observatory-2),as well as WLG(Waliguan)background station observations,are compared with those of GOSAT.The annual CO2 retrieved from GOSAT in East China ranged from 398.96±0.24 ppm in 2014 to 407.39±0.20 ppm in 2017,with a growth rate of 2.82±0.15 ppm yr^−1,which were higher than in other regions of China.The seasonal cycle presented a maximum in spring and a minimum in summer or autumn.Higher values were mainly concentrated in the coastal areas of Zhejiang Province,and lower values were concentrated in Jiangxi and the north of Fujian Province.CO2 observed in Fujian and parts of Jiangxi increased by less than 1.0 ppm during 2014–15,but enhanced significantly by more than 5.0 ppm during 2015–16,perhaps influenced by local emissions and global impacts.We calculated year-to-year CO2 enhancements in the Yangtze River Delta region during 2014–17 that were relatively low and stable,due to the region’s carbon emissions control and reduction policies.The annual and seasonal amplitudes of CO2 retrieved from AIRS were lower than those from GOSAT in East China,probably owing to the CO2 retrieved from AIRS better reflecting the characteristics of the mid-troposphere,while GOSAT is more representative of near-surface CO2.The spatial and temporal distribution characteristics of CO2 retrieved from OCO-2 were close to those from GOSAT in East China.
基金supported by the National Natural Science Foundation of China(Grant No.31701928)the Chongqing Natural Science Foundation(Grant No.cstc2017jcyjAX0226)+1 种基金the Science and Technology Research Program of Chongqing Municipal Education Commission(Grant No.KJ1712305)research grants of Yangtze Normal University(Grant Nos.2016XJQN07,2016KYQD19).
文摘Tumorous stem mustard is well known for its swollen stem from which pickled“Fuling Mustard”is made.The molecular mechanisms governing the formation of the modified swollen stems are still poorly understood.This paper aims to identify candidate genes involved in the developmental regulation of the swollen stems.We sought to map previously published transcriptome datasets for Brassica juncea,including those derived from swollen stems at four different developmental stages and a mutant variety without swollen stems.Using pairwise comparisons of the five datasets,we identified 31368 differentially expressed genes(DEGs).A total of 55 DEGs related to plant hormone signal transduction and 259 continuously up-or downregulated transcription factors were identified during stem development using Gene Ontology(GO)analysis.Quantitative real-time PCR(qRT-PCR)results showed that the expressions of 12 important candidate DEGs were consistent with RNA-seq results.Our study provided digital gene expression profiling and a dynamic view of the swollen stem development process.Furthermore,we identified candidate genes for further studies on mechanisms of modified stem development in non-model species.
基金supported by the National Natural Science Foundation of China(No.51978588)。
文摘To solve the problem of deformation and cracking of ballastless track slab under temperature load,a composite oxide and a series of heat-reflective coating samples were prepared.At the microscopic level,the elemental composition and optical properties of the materials prepared were analyzed by Fourier transform infrared spectroscopy and ultraviolet-visible spectroscopy,and the feasibility of Ce/Si/Ti oxide as functional fillers for heat-reflective coatings of track slabs was demonstrated.At the macro level,by designing and assembling an indoor sunlight simulation test device,the surface and internal temperatures of the coated and uncoated concrete specimens were analyzed and studied,and the macroscopic cooling effect of the coatings was evaluated.Also,to study the engineering application effect of the track slab thermal insulation reflective coating,COMSOL was used to build a 3D calculation model of the heat transfer deformation of the ballastless track slab structure.The research results showed that:Ce/Si/Ti oxide has strong reflectivity and can reflect 95%of infrared light;it has good ultraviolet(UV)shielding ability and can absorb more than 65%of the UV light.The TiO2 coating can reduce the temperature of the concrete surface by 6–11℃and that of the inside of the concrete by 10–14℃;the cooling effect decreases evenly with the increase of air temperature.The Ce/Si/Ti oxide coating can reduce the surface temperature of the concrete by 16℃and that of the inside of the concrete by 15℃.In addition,the cooling effect is basically not affected by the air temperature,and it changes non-linearly with the increase of the Ce/Si/Ti oxide content.Numerical calculation shows that the heat reflective coating can reduce the surface temperature and internal temperature difference of the track slab by 11.54–21.31℃,and the vertical displacement of the track slab can be reduced by about 35%–70%.Considering the cooling effect,the adhesion strength,and the engineering application effect of the coating,the optimal doping amount of Ce/Si/Ti oxide is 40%,and that coating is the most suitable for use as a ballastless track heat reflective coating.
基金Q.H.X.gratefully acknowledges the support from Singapore Ministry of Education via AcRF Tier 3 Programme(No.MOE2018-T3-1-002)Tier 2 project(No.MOE2017-T2-1-040)Singapore National Research Foundation via NRF-ANR project(No.NRF2017-NRF-ANR0052D-Chiral).
文摘Fundamental understandings on the dynamics of charge carriers and excitonic quasiparticles in semiconductors are of central importance for both many-body physics and promising optoelectronic and photonic applications.Here,we investigated the carrier dynamics and many-body interactions in two-dimensional(2D)transition metal dichalcogenides(TMDs),using monolayer WS2 as an example,by employing femtosecond broadband pump-probe spectroscopy.Three time regimes for the exciton energy renormalization are unambiguously revealed with a distinct red-blue-red shift upon above-bandgap optical excitations.We attribute the dominant physical process in the three typical regimes to free carrier screening effect,Coulombic exciton-exciton interactions and Auger photocarrier generation,respectively,which show distinct dependence on the optical excitation wavelength,pump fluences and/or lattice temperature.An intrinsic exciton radiative lifetime of about 1.2 picoseconds(ps)in monolayer WS2 is unraveled at low temperature,and surprisingly the efficient Auger nonradiative decay of both bright and dark excitons puts the system in a nonequilibrium state at the nanosecond timescale.In addition,the dynamics of trions at low temperature is observed to be significantly different from that of excitons,e.g.,a long radiative lifetime of^108.7 ps at low excitation densities and the evolution of trion energy as a function of delay times.Our findings elucidate the dynamics of excitonic quasiparticles and the intricate many-body physics in 2D semiconductors,underpinning the future development of photonics,valleytronics and optoelectronics based on 2D semiconductors.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.61675090,21776110,and 61705020)the National Youth Foundation of China(Nos.61405072,61704065,and 61705078)+2 种基金the Program for the Development of Science and Technology Jilin Province(Nos.20200301043RQ,20200201022JC,20190103002JH,and 20180520179JH)the Thirteenth Five-Year Program for Science and Technology of Education Department of Jilin Province(Grant Numbers JJKH20200418KJ,JJKH20191018KJ,JJKH20191022KJ,and JJKH20190550KJ)Tianjin Natural Science Foundation(Grant Number 16JCYBJC41400).
文摘Emerging technologies in the field of environmental remediation are becoming increasingly significant owing to the increasing demand for eliminating significant amounts of pollution in water,soil,and air.We designed and synthesized MoS 2/Fe 2 O 3 heterojunction nanocomposites(NCs)as multifunctional materials that are easily separated and reused.The trace detection performance of the prepared sample was examined using bisphenol A(BPA)as the probe molecule,with limits of detection as low as 10−9 M;this detection limit is the lowest among all reported semiconductor substrates.BPA was subjected to rapid photocatalytic degradation by MoS_(2)/Fe_(2)O_(3) NCs under ultraviolet irradiation.The highly recyclable MoS_(2)/Fe_(2)O_(3) NCs exhibited photo-Fenton catalytic activity for BPA and good detection ability when reused as a surface-enhanced Raman scattering(SERS)substrate after catalysis.The SERS and photocatalysis mechanisms were proposed while considering the effects of the Z-scheme charge-transfer paths,three-dimensional flower-like structures,and dipole–dipole coupling.Moreover,the prepared MoS_(2)/Fe_(2)O_(3) NCs were successfully applied in the detection of BPA in real lake water and milk samples.Herein,we present insights into the development of MoS_(2)/Fe_(2)O_(3) materials,which can be used as multifunctional materials in chemical sensors and in photocatalytic wastewater treatments for the removal of recalcitrant organic pollutants.
基金National Natural Science Foundation of China,Grant/Award Numbers:52177154,51807144,51877155。
文摘In 2018-2019,two types of rocket-triggered lightning tests,that is,striking to ground and distribution line,were conducted in Guangdong,China.The main focus of this paper is to compare the waveform parameters of the return strokes(RS)from the two tests.For current,the 10%-90%risetime of RS from lightning striking to distribution line is 2.4 times higher than that striking to ground,and the differences in the other parameters are small.For close magnetic field,the RS from lightning striking to distribution line have a lower peak(30%lower after considering the peak current)and a larger risetime and half-peak width time;besides,it is necessary to divide the front edge of the close magnetic field waveform into two parts:leader(BL)and return stroke(BRS).For close electric field,the close RS electric field peak(ERS)was less sensitive to distance than the leader electric field peak(EL).For far electric field,the differences in waveform parameters of RS from the two tests were not significant,but after considering the peak current,the normalised initial electric field peak(EP)of RS from lightning striking to distribution line was 14%lower than that striking to ground.
基金Project supported by the Science Fund for Creative Research Groups of National Natural Science Foundation of China(No.51821093)。
文摘The double-threshold method has been widely used in ultrasonic flow measurement to determine time-of-flight(TOF)due to its low cost and ease of implementation.Performance of this method is negatively affected by the cycle-skip phenomenon which occurs frequently under inconstant working conditions,especially varied fluid temperature.This paper proposes a method to suppress the phenomenon to facilitate reliable determination of TOF in ultrasonic flow measurement.First,the double-threshold method is used to generate a feature point to segment the signal.Second,based on the correlation coefficient and signal power,judgement factors of individual signal periods are calculated to determine signal onset.Finally,a valid zero crossing which has a constant lag from the onset is selected to determine the TOF.Thus,the cycle-skip phenomenon is suppressed.Two additional modifications are proposed to eliminate the influence of varied signal frequency and low sampling rate.The proposed method was validated by an experiment based on an ultrasonic water flow sensor.Results showed that the frequently appearing cycle-skip phenomenon can be successfully suppressed by the proposed method.
基金This study was supported by grants from the National Natural Science Foundation of China(81403029)the Natural Science Foundation of Shanghai(19ZR1449100)+2 种基金the Science and Technology Commission of Shanghai Municipality(19JC1415500)the Science and Technology Commission of Shanghai Municipality(18410760600)the International Partnership Program of Chinese Academy of Sciences(Grant No.GJHZ1850).
文摘Polyetheretherketone(PEEK)has been used as an implant material because it has similar mechani-cal properties to natural bone.However,inferior osseointegration and bioinertness hamper the clinical application of PEEK.In this study,the surfaces of sulfonated three-dimensional(3D)PEEK porous structures were loaded with different concentrations of strontium ranelate,a compound commonly used in the treatment or prevention of osteoporosis by promoting bone formation and inhibiting bone resorption.Field-emission scanning electron microscopy was used to characterize the topography of the structures,elemental carbon,oxygen and strontium contents were mea-sured by X-ray photoelectron spectroscopy,and surface zeta potentials and water-contact angle were also measured.The results indicated that strontium ranelate was successfully loaded onto the 3D porous structures.In vitro cellular results showed that strontium ranelate-treated sulfonated PEEK(SP-SR)strengthened the adhesion of MC3T3-E1 cells.The activity of alkaline phosphatase,collagen secretion and extracellular matrix mineralization deposition of MC3T3-E1 cells were also improved on the surface of SP-SR.These results indicate that SP-SR could serve a new implant candidate for surgical treatment.
基金supported by the National Natural Science Foundation of China(51673139,91633301)a Priority Academic Program Development of Jiangsu Higher Education Institutions,State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials.
文摘Residual water-induced decomposition is one of the dominant reasons for the decay of power conversion efficiency (PCE) in perovskite solar cells (Pero-SCs). To solve this problem, we introduce traces amount of sodium hyaluronate (SH) into the perovskite active layer to reduce the remaining water during the preparation of perovskite films. Unlike the traditionally adopted passive protection of perovskite from exterior water by low surface energy coatings, this study provides active control of the interior water by the addition of a water adsorbent into the perovskite films. The encapsulated Pero-SCs with SH retain approximately 70% of their initial PCE in 4000 h, while those without SH retain 32% of their initial PCE in 1000 h under the dark and ambient atmosphere. The unencapsulated Pero-SCs with SH stored in N2 atmosphere maintain over 94% of the initial PCE in 3000 h at room temperature away from light and remain over 88% of the initial PCE in 2000 h even the devices are heated to 70 °C. It has been proven that the improved stability is mainly due to the well-controlled residual water in perovskite films. Concomitantly, the PCE of p-i-n solar cells based on (FAPbI3)0.85(MAPbBr3)0.15 is improved from 19.34% to 21.54%.
基金supported by the National Natural Science Foundation of China (No.30471255)the Program for New Century Excellent Talents in University(No.NCET-06-0913)
文摘The adsorption properties of Cu 2+ -loaded montmorillonite clays (MMT-Cu) for Escherichia coli K 88 as a function of time,bacteria concentrations,pH,ionic strength and temperature were investigated.The results showed that the bacteria adsorption onto MMT-Cu surface reached equilibrium after 90 min.The percentages of E.coli K 88 adsorbed onto the surfaces of MMT-Cu and montmorillonite clays (MMT) at equilibrium were 88.9% and 56.5%,respectively.Scanning electron microscopy revealed that a lot of E.coli K 88 adhered to the surface of MMT-Cu.The zeta potential of MMT-Cu was relatively high as compared to that of MMT.The adsorptive ability of MMT-Cu for E.coli K 88 was higher than that of MMT (P < 0.05).Moreover,pH,ionic strength and temperature produced a strong influence on the extent of E.coli K 88 adsorption to surface of MMT-Cu and MMT.The mechanism of adsorption of E.coli onto MMT-Cu may involve electrostatic attraction and physiochemical properties of bacterial cell walls and minerals surfaces.
