A visible-light photocatalyst was prepared by calcination of the hydrolysis product of Ti(SO_4)_2 with ammonia as precipitator. The color of this photocatalyst was vivid yellow. It could absorb light under 550 nm wave...A visible-light photocatalyst was prepared by calcination of the hydrolysis product of Ti(SO_4)_2 with ammonia as precipitator. The color of this photocatalyst was vivid yellow. It could absorb light under 550 nm wavelength. The crystal structure of anatase was characterized by XRD. The structure analysis result of X-ray fluorescence(XRF) shows that doped-nitrogen was presented in the sample. The photocatalytic activities were evaluated using methyl orange and phenol as model pollutants. The photocatalytic activities of samples were increasing gradually with calcination temperature from 400℃ to 700℃ under UV irradiation. It can be seen that the degradation of methyl orange follows zero-order kinetics. However, the calcination temperatures have no significant influence on the degradation of phenol under sunlight. The N-doped catalyst shows higher activity than the bare one under solar irradiation.展开更多
A new method for recharging active medical implant(AMI)in vitro based on incoherent light source and results of the simulation experiments are proposed.Firstly,the models of the AMI recharging method based on incohe...A new method for recharging active medical implant(AMI)in vitro based on incoherent light source and results of the simulation experiments are proposed.Firstly,the models of the AMI recharging method based on incoherent light source in vitro are developed,which include the models of an incoherent light source and skin tissue.Secondly,simulation experiments of the incoherent light source of the AMI recharging process in vitro based on the Monte Carlo(MC)method are carried out.Finally,absorbed fractions of different layers and distributions of density along x axis of the tissue model and other important conclusions have been achieved.展开更多
Purpose:The aim of the current study was to investigate the association of accelerometer-measured sleep duration and different intensities of physical activity(PA)with the risk of incident type 2 diabetes in a populat...Purpose:The aim of the current study was to investigate the association of accelerometer-measured sleep duration and different intensities of physical activity(PA)with the risk of incident type 2 diabetes in a population-based prospective cohort study.Methods:Altogether,88,000 participants(mean age=62.2±7.9 years,mean±SD)were included from the UK Biobank.Sleep duration(short:<6 h/day;normal:6-8 h/day;long:>8 h/day)and PA of different intensities were measured using a wrist-won accelerometer over a 7-day period between 2013 and 2015.PA was classified according to the median or World Health Organization-recommendation:total volume of PA(high,low),moderate-to-vigorous PA(MVPA)(recommended,not recommended),and light-intensity PA(high,low).Incidence of type 2diabetes was ascertained using hospital records or death registries.Results:During a median follow-up of 7.0 years,1615 incident type 2 diabetes cases were documented.Compared with normal sleep duration,short(hazard ratio(HR)=1.21,95%confidence interval(95%CI):1.03-1.41)but not long sleep duration(HR=1.01,95%CI:0.89-1.15)was associated with excessive type 2 diabetes risk.This increased risk among short sleepers seems to be protected against by PA.Compared with normal sleepers with high or recommended PA,short sleepers with low volume of PA(HR=1.81,95%CI:1.46-2.25),not recommended(below the World Health Organization-recommended level of)MVPA(HR=1.92,95%CI:1.55-2.36),or low light-intensity PA(HR=1.49,95%CI:1.13-1.90)had a higher risk of type 2 diabetes,while short sleepers with a high volume of PA(HR=1.14,95%CI:0.88-1.49),recommended MVPA(HR=1.02,95%CI:0.71-1.48),or high light-intensity PA(HR=1.14,95%CI:0.92-1.41)did not.Conclusion:Accelerometer-measured short but not long sleep duration was associated with a higher risk of incident type 2 diabetes.A higher level of PA,regardless of intensity,potentially ameliorates this excessive risk.展开更多
Bismuth containing nanomaterials recently received increasing attention with respect to environmental applications because of their low cost, high stability and nontoxicity. In this work, Bi–Bi_2O_2CO_3 heterojunctio...Bismuth containing nanomaterials recently received increasing attention with respect to environmental applications because of their low cost, high stability and nontoxicity. In this work, Bi–Bi_2O_2CO_3 heterojunctions were fabricated by in-situ decoration of Bi nanoparticles on Bi_2O_2CO_3 nanosheets via a simple hydrothermal synthesis approach. X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM) and high-resolution TEM(HRTEM) were used to confirm the morphology of the nanosheet-like heterostructure of the Bi–Bi_2O_2CO_3 composite. Detailed ultrafast electronic spectroscopy reveals that the in-situ decoration of Bi nanoparticles on Bi_2O_2CO_3 nanosheets exhibit a dramatically enhanced electron-hole pair separation rate, which results in an extraordinarily high photocatalytic activity for the degradation of a model organic dye, methylene blue(MB) under visible light illumination. Cycling experiments revealed a good photochemical stability of the Bi–Bi_2O_2CO_3 heterojunction under repeated irradiation. Photocurrent measurements further indicated that the heterojunction incredibly enhanced the charge generation and suppressed the charge recombination of photogenerated electron-hole pairs.展开更多
To elucidate the mechanism of photodynamic damage of cells, the effect of HPD plus light on transcriptlonal ectlvlty In the mucleus Isolate from the normal rat liver was studied in vitor by 3H- UTP incorporation into ...To elucidate the mechanism of photodynamic damage of cells, the effect of HPD plus light on transcriptlonal ectlvlty In the mucleus Isolate from the normal rat liver was studied in vitor by 3H- UTP incorporation into RNA. Measurements of fluorescence spectrum showed that HPD was bound to the nucleus and its fluorescence Intensity Increased with the Increase of HPD concentration. The experimental results Indicated that no changes could be observed when either HPD or light was used alone. Whereas the nuclear transcription activity was found to be inhibited significantly by both HPD and light treatment, and the degree of Inhibition was dependent on the HPD concentration and the time of exposure to light. After treatment by 3 μg/ ml HPD, the inhibition rate of the nuclear transcription activity was 23% ,45% ,69% ,80% and 90%, respectively for light exposure of 2, 5, 10, 20 and 30 minutes. Our results suggested that dose-dependent decreases in the nuclear transcription activity, and marked inhibition of the activity was found in the range from 3 to 7 μg/ml HPD following exposure to light.展开更多
The visible-light-driven hydrogen evolution is extremely important,but the poor charge transfer capa-bility,a sluggish evolution rate of hydrogen,and severe photo-corrosion make photocatalytic hydrogen evolution impra...The visible-light-driven hydrogen evolution is extremely important,but the poor charge transfer capa-bility,a sluggish evolution rate of hydrogen,and severe photo-corrosion make photocatalytic hydrogen evolution impractical.In this study,we present 1D/2D ReS_(2)-CdS hybrid nanorods for photocatalytic hy-drogen evolution,comprised of a ReS_(2)nanosheet layer grown on CdS nanorods.We found that precise control of the contents of the ReS_(2)nanosheet layer allows for manipulating the electronic structure of Re in the ReS_(2)-CdS hybrid nanorods.The ReS_(2)-CdS hybrid nanorods with optimal ReS_(2)nanosheet layer content dramatically improve photocatalytic hydrogen evolution activity.Notably,photocatalytic hydro-gen evolution activity(64.93 mmol g^(−1)h^(−1))of ReS_(2)-CdS hybrid nanorods with ReS_(2)nanosheet layers(Re/Cd atomic ratio of 0.051)is approximately 136 times higher than that of pure CdS nanorods under visible light irradiation.Furthermore,intimated coupling of the ReS_(2)nanosheet layer with CdS nanorods reduced the surface trap-site of the CdS nanorods,resulting in enhanced photocatalytic stability.The de-tailed optical and electrical investigations demonstrate that the optimal ReS_(2)nanosheet layer contents in the ReS_(2)-CdS hybrid nanorods can provide improved charge transfer capability,catalytic activity,and light absorption efficiency.This study sheds light on the development of photocatalysts for highly efficient photocatalytic hydrogen evolution.展开更多
The paper puts forward a method on controlling the AM-OLED panel to display image with high gray scale levels. It also gives an ASIC design sample to implement this method. A twenty sub-fields scan scheme has been tak...The paper puts forward a method on controlling the AM-OLED panel to display image with high gray scale levels. It also gives an ASIC design sample to implement this method. A twenty sub-fields scan scheme has been taken into use in the chip to display 256 gray scale levels on a QVGA resolution AM-OLED display screen. The functions of image scaling and rotating have also been implemented for multiply application. The simulation and chip test result show that the chip design has met the design requirements.展开更多
Background: Although emerging research is demonstrating the potential health impact of exergaming,investigations have primarily been conducted in laboratory settings among small samples with short-term interventions.I...Background: Although emerging research is demonstrating the potential health impact of exergaming,investigations have primarily been conducted in laboratory settings among small samples with short-term interventions.Information on the effectiveness of exergaming in underserved children's objective physical activity(PA) in population-based settings is also scarce.Moreover,most empirical studies have only included 1 type of exergame in the intervention.Therefore,this study's purpose was to investigate the long-term impact of a multigame exergaming intervention among underserved children integrated within school curricula.Specifically,this study examined the effect of exergaming on children's accelerometer-determined sedentary behavior(SB),light PA,moderate-to-vigorous PA(MVPA),and energy expenditure(EE) over 2 years as compared with regular physical education(PE) classes.Methods: A total of 261 second-and third-grade children(134 girls,127 boys; mean age 8.27 years) were recruited from 2 Texas elementary schools.Children's pre-test 3-day SB,light PA,MVPA,and EE at school were assessed in the fall of 2012.Participants were assigned to 1 of 2groups:(1) exergaming/PE group(125 min weekly of exergaming-based PA program) and (2) comparison group(125 min weekly of PE).PA(SB,light PA,and MVPA) and EE outcome variables were assessed again in 2013(post-test) and 2014(follow-up).Results: Significant time effects were observed for SB(F(1,162)=25.0,p<0.01,η~2= 0.14),light PA(F(1,162)=9.6,p<0.01,η~2= 0.06),and MVPA(F(1,162)=6.2,p=0.01,η~2= 0.04) but not for EE(F(1,162)=0.63,p>0.05,η~2= 0.004).Subsequent pairwise comparisons revealed significant increases from pre-to post-test for light PA(p<0.01),MVPA(p<0.01),and EE(p=0.02) with no changes in SB(p>0.05).Conversely,significant decreases occurred in light PA(p<0.01) from post-test to follow-up with no differences seen in MVPA(p=0.08) and EE(p=0.06) over the same time period.A significant increase was seen,however,for SB from post-test to follow-up.Conclusion: Exergaming PE can have the same positive effect on children's light PA,MVPA,and EE as regular PE.More research is necessary to discern how to promote long-term PA participation after conclusion of the intervention.展开更多
Numerous studies links movement activity(e.g.,physical activity,sedentary behavior[SB],and sleep)with mental health or illness indicators during the COVID-19 pandemic;however,research has typically examined time-use b...Numerous studies links movement activity(e.g.,physical activity,sedentary behavior[SB],and sleep)with mental health or illness indicators during the COVID-19 pandemic;however,research has typically examined time-use behaviors independently,rather than considering daily activity as a 24-hour time-use composition.This cross-sec-tional study aimed to use compositional isotemporal analysis to estimate the association between reallocation of time-use behaviors and depression symptoms in young adults in China.Participants(n=1475;68.0%of female;20.7[1.60]years)reported their time spent in moderate to vigorous physical activity(MVPA),light physical activ-ity(LPA),SB,and sleep.Replacing SB with sleep,LPA,and MVPA at 5,10,or 15 min was significantly associated with lower estimated depression symptoms scores.For example,adding MVPA from SB at 15 min was associated with lower depression symptoms scores(estimated difference:-0.13[-0.17,-0.09]).The associations between reallocation of time use behaviors with depression symptoms scores were slightly differentiated.Our results emphasize the importance of increased MVPA and decreased SB as well as their mutual replacements for lowering the risks of depression symptoms in young adults during the COVID-19 pandemic.Our results can inform policy to develop effective plans and strategies for mental health promotion.展开更多
Protein S-sulfenylation(protein sulfenic acid),as one of the most significant oxidative post-translational modifications(OxiPTMs),plays a vital role in regulating protein function.A variety of activity-based probes ha...Protein S-sulfenylation(protein sulfenic acid),as one of the most significant oxidative post-translational modifications(OxiPTMs),plays a vital role in regulating protein function.A variety of activity-based probes have been developed to profile sulfenic acid in living cells.However,due to the transient presence and low content of sulfenic acid in living cell,high doses of probes are needed to achieve efficient labeling.More importantly,current probes have no temporal control over sulfenic acid labeling.To overcome these limitations,two caged cysteine sulfenic acid probes DYn-2-ONB and DYn-2-Cou with either an o-nitrobenzyl or coumarin protecting group were developed in this study.Both probes can be efficiently uncaged via irradiation to produce the active C-nucleophile probe DYn-2.Labeling assay in living cells demonstrated DYn-2-ONB exhibited better labeling capacity compared with DYn-2,providing it as a powerful tool for improved monitoring of protein S-sulfenylation in living cells.展开更多
W, N co-doped TiO2 nanoparticles were synthesized by a sol-gel method. The prepared samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), trans- mission elect...W, N co-doped TiO2 nanoparticles were synthesized by a sol-gel method. The prepared samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), trans- mission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-1R), X-ray photoelectron spectroscopy (XPS) and diffuse reflectance spectrophotometry (DRS). The results showed that the co- doped photocatalysts were essentially uniform spherical particles with the smallest particle size of 22.5 nm. Compared to un-doped TiO2, N-TiO2 and P-25, the absorption edge of the W, N co-doped TiO2 shifted to longer wavelength and its photocatalytic activity for degradation of methyl orange (MO) under Xe-lamp (350W) was higher.展开更多
The photocatalytic degradation of methylene blue(MB) over Fe-doped CaTiO3 under UV-visible light was investigated. The as-prepared samples were characterized using X-ray diffraction(XRD), scanning electron microsc...The photocatalytic degradation of methylene blue(MB) over Fe-doped CaTiO3 under UV-visible light was investigated. The as-prepared samples were characterized using X-ray diffraction(XRD), scanning electron microscope(SEM) equipped with an energy dispersive spectrometer(EDS) system, Fourier transform infrared spectra(FT-IR), and UV-visible diffuse reflectance spectroscopy(DRS). The results show that the doping with Fe significantly promoted the light absorption ability of CaTiO3 in the visible light region. The Fe-doped CaTiO3 exhibited higher photocatalytic activity than CaTiO3 for the degradation of MB.However, the photocatalytic activity of the Fe-doped CaTiO3 was greatly influenced by the calcination temperature during the preparation process. The Fe-doped CaTiO3 prepared at500°C exhibited the best photocatalytic activity, with degradation of almost 100% MB(10 ppm)under UV-visible light for 180 min.展开更多
A series of MoS_2/ZnO compound photocatalysts with different mass ratios were successfully prepared by hydrothermal method. The X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), scanning electron microsco...A series of MoS_2/ZnO compound photocatalysts with different mass ratios were successfully prepared by hydrothermal method. The X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), scanning electron microscope(SEM) and UV-vis absorption were used to characterize the prepared MoS_2/ZnO photocatalysts. It was proved that the combination of Mo S2 and Zn O can increase the content of oxygen vacancies on surface of Zn O, thus improving the light absorption capacity in visible light region and reducing the band gap of Zn O. And the photocatalytic performance of Zn O was improved. Experimental results show that the MoS_2/ZnO(3 wt%) compound has the highest degradation rate for methylene blue(MB) under visible light, which means that it has the best photocatalytic activity among all the prepared samples.展开更多
The photoisomerization properties of azo derivatives have been widely used in the fields of materials and biology.One serious restriction to the development of functional azo-based materials is the necessity to trigge...The photoisomerization properties of azo derivatives have been widely used in the fields of materials and biology.One serious restriction to the development of functional azo-based materials is the necessity to trigger switching by UV light,which damage the corresponding surfaces and penetrate only partially through the matter.Therefore,developing the visible and near-infrared light activated azo switches can solve this problem.This review provides a summary of molecular design strategies for driving the isomerization of azo derivatives with visible light and near-infrared light:(1) smart design directly excited by visible light,(2) the addition of upconversion nanoparticles,(3) the employment of twophoton absorption,(4) indirect excitation in combination with metal sensitizer.展开更多
Density functional theory (DFT) plays a significant role in the development of visible light responsive photocatalysts. Based on the first-principles plane-wave ultrasoft pseudopotential (USPP) method, the crystal...Density functional theory (DFT) plays a significant role in the development of visible light responsive photocatalysts. Based on the first-principles plane-wave ultrasoft pseudopotential (USPP) method, the crystal structures of α,β,γ, and 5-Bi2O3 were optimally calculated for the total density of states (TDOS) and the partial density of states (PDOS) of Bi, O atoms. The calculation for Ti(IV) doped Bi2O3 supercell was carried out. The effects of Ti(IV)-doping on the electron structures and light absorption properties of various Bi2O3 were analyzed. The results showed that Ti 3d orbital appeared in the forbidden band of Bi2O3 and hybridized with O 2p, Bi 6p orbitals. The narrowed band gap (Eg) and red-shift of light absorption edge are responsible for the enhanced photoeatalytic activity of Bi2O3. The Ⅱ-Bi2O3 and Ti-doped β-Bi2O3 were prepared by a hydrotherrnal synthesis method. The improvement of the photoeatalytic activity of Bi2O3 has also been verified by the characteristics of the UV-vis diffuse reflection spectrum and the experimental evaluation of the photocatalytic degradation of crystal violet in aqueous solution.展开更多
Polymeric-inorganic nanocomposite catalysts were synthesized by facile one-pot chemical polymerization of pyrrole in the presence of titanium dioxide nanoparticles. The electrical, optical, photovoltaic performance of...Polymeric-inorganic nanocomposite catalysts were synthesized by facile one-pot chemical polymerization of pyrrole in the presence of titanium dioxide nanoparticles. The electrical, optical, photovoltaic performance of dye sensitized solar cell(DSSC) and visible light driven photocatalytic activities of the nanocomposite were investigated. The prepared nanocomposite displays excellent photo-activity, attaining 100% degradation of methyl orange dye in 60 min under visible light source while 55% for pure TiO_2 under similar experimental conditions. The photovoltaic performance of the polypyrrole-titanium dioxide(PPy-TiO_2) nanocomposite has a 51.4% improvement with a photo-conversion efficiency of 8.07% as compared to pure TiO_2 based DSSC. By comparing the physical mixture of the PPy-TiO_2 nanocomposite and pristine TiO_2, the enhanced activity of the PPy-TiO_2 nanocomposite can be attributed to the reduced charge transfer resistance, outstanding electrical conductance of the PPy, the nano-sized structure of TiO_2 and their synergetic effect. Furthermore, the PPy-TiO_2 nanocomposite shows excellent electrical conductivity and isothermal stability under ambient conditions below 110?C.展开更多
The chemical structure of newly synthesized cationic surfactants based on Schiff base was confirmed using Fourier transform infrared spectroscopy,proton nuclear magnetic resonance spectroscopy,and mass spectroscopy.Th...The chemical structure of newly synthesized cationic surfactants based on Schiff base was confirmed using Fourier transform infrared spectroscopy,proton nuclear magnetic resonance spectroscopy,and mass spectroscopy.The synthesized surfactants were used in the synthesis of silver nanoparticles by a simple one-step method.The silver nanoparticle(AgNPs) formation was confirmed using transmission electron microscopy(TEM),electron diffraction(SAED),dynamic light scattering(DLS),and energy dispersive X-ray spectroscopy(EDX).The structure of the surfactant played an important role in the synthesis process.Increasing the hydrophobic chain length,the stability,and the amount of surfactant increased the quantity of AgNPs formed.The surface activity of the synthesized cationic surfactants was determined using surface tension measurements at three different temperatures.The synthesized surfactants showed a high tendency toward adsorption and micellization.Increasing the hydrophobic chain length of the synthesized surfactant increased its adsorption.Screening the synthesized cationic surfactants and their nano-form against bacteria and fungi showed that they are highly effective.The silver nanoparticles enhanced the biological activity of the synthesized cationic surfactants.展开更多
文摘A visible-light photocatalyst was prepared by calcination of the hydrolysis product of Ti(SO_4)_2 with ammonia as precipitator. The color of this photocatalyst was vivid yellow. It could absorb light under 550 nm wavelength. The crystal structure of anatase was characterized by XRD. The structure analysis result of X-ray fluorescence(XRF) shows that doped-nitrogen was presented in the sample. The photocatalytic activities were evaluated using methyl orange and phenol as model pollutants. The photocatalytic activities of samples were increasing gradually with calcination temperature from 400℃ to 700℃ under UV irradiation. It can be seen that the degradation of methyl orange follows zero-order kinetics. However, the calcination temperatures have no significant influence on the degradation of phenol under sunlight. The N-doped catalyst shows higher activity than the bare one under solar irradiation.
基金Supported by the Excellent Young Scholars Research Fund of Beijing Institute of Technology(3040012211310)the Basic Research Fund of Beijing Institute of Technology(20120442010)
文摘A new method for recharging active medical implant(AMI)in vitro based on incoherent light source and results of the simulation experiments are proposed.Firstly,the models of the AMI recharging method based on incoherent light source in vitro are developed,which include the models of an incoherent light source and skin tissue.Secondly,simulation experiments of the incoherent light source of the AMI recharging process in vitro based on the Monte Carlo(MC)method are carried out.Finally,absorbed fractions of different layers and distributions of density along x axis of the tissue model and other important conclusions have been achieved.
基金supported by the National Key R&D Program of China(2021YFC2501500)National Natural Science Foundation of China(82171476)。
文摘Purpose:The aim of the current study was to investigate the association of accelerometer-measured sleep duration and different intensities of physical activity(PA)with the risk of incident type 2 diabetes in a population-based prospective cohort study.Methods:Altogether,88,000 participants(mean age=62.2±7.9 years,mean±SD)were included from the UK Biobank.Sleep duration(short:<6 h/day;normal:6-8 h/day;long:>8 h/day)and PA of different intensities were measured using a wrist-won accelerometer over a 7-day period between 2013 and 2015.PA was classified according to the median or World Health Organization-recommendation:total volume of PA(high,low),moderate-to-vigorous PA(MVPA)(recommended,not recommended),and light-intensity PA(high,low).Incidence of type 2diabetes was ascertained using hospital records or death registries.Results:During a median follow-up of 7.0 years,1615 incident type 2 diabetes cases were documented.Compared with normal sleep duration,short(hazard ratio(HR)=1.21,95%confidence interval(95%CI):1.03-1.41)but not long sleep duration(HR=1.01,95%CI:0.89-1.15)was associated with excessive type 2 diabetes risk.This increased risk among short sleepers seems to be protected against by PA.Compared with normal sleepers with high or recommended PA,short sleepers with low volume of PA(HR=1.81,95%CI:1.46-2.25),not recommended(below the World Health Organization-recommended level of)MVPA(HR=1.92,95%CI:1.55-2.36),or low light-intensity PA(HR=1.49,95%CI:1.13-1.90)had a higher risk of type 2 diabetes,while short sleepers with a high volume of PA(HR=1.14,95%CI:0.88-1.49),recommended MVPA(HR=1.02,95%CI:0.71-1.48),or high light-intensity PA(HR=1.14,95%CI:0.92-1.41)did not.Conclusion:Accelerometer-measured short but not long sleep duration was associated with a higher risk of incident type 2 diabetes.A higher level of PA,regardless of intensity,potentially ameliorates this excessive risk.
基金DST,India for financial grant(SB/S1/PC-011/2013)DAE(India)for financial grant 2013/37P/73/BRNS,NTH-School‘‘Contacts in Nanosystems:Interactions,Control and Quantum Dynamics’’+1 种基金the Braunschweig International Graduate School of Metrology(IGSM)DFG-RTG 1952/1,Metrology for Complex Nanosystems
文摘Bismuth containing nanomaterials recently received increasing attention with respect to environmental applications because of their low cost, high stability and nontoxicity. In this work, Bi–Bi_2O_2CO_3 heterojunctions were fabricated by in-situ decoration of Bi nanoparticles on Bi_2O_2CO_3 nanosheets via a simple hydrothermal synthesis approach. X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM) and high-resolution TEM(HRTEM) were used to confirm the morphology of the nanosheet-like heterostructure of the Bi–Bi_2O_2CO_3 composite. Detailed ultrafast electronic spectroscopy reveals that the in-situ decoration of Bi nanoparticles on Bi_2O_2CO_3 nanosheets exhibit a dramatically enhanced electron-hole pair separation rate, which results in an extraordinarily high photocatalytic activity for the degradation of a model organic dye, methylene blue(MB) under visible light illumination. Cycling experiments revealed a good photochemical stability of the Bi–Bi_2O_2CO_3 heterojunction under repeated irradiation. Photocurrent measurements further indicated that the heterojunction incredibly enhanced the charge generation and suppressed the charge recombination of photogenerated electron-hole pairs.
文摘To elucidate the mechanism of photodynamic damage of cells, the effect of HPD plus light on transcriptlonal ectlvlty In the mucleus Isolate from the normal rat liver was studied in vitor by 3H- UTP incorporation into RNA. Measurements of fluorescence spectrum showed that HPD was bound to the nucleus and its fluorescence Intensity Increased with the Increase of HPD concentration. The experimental results Indicated that no changes could be observed when either HPD or light was used alone. Whereas the nuclear transcription activity was found to be inhibited significantly by both HPD and light treatment, and the degree of Inhibition was dependent on the HPD concentration and the time of exposure to light. After treatment by 3 μg/ ml HPD, the inhibition rate of the nuclear transcription activity was 23% ,45% ,69% ,80% and 90%, respectively for light exposure of 2, 5, 10, 20 and 30 minutes. Our results suggested that dose-dependent decreases in the nuclear transcription activity, and marked inhibition of the activity was found in the range from 3 to 7 μg/ml HPD following exposure to light.
基金supported by the National Re-search Foundation of Korea(Nos.NRF-2020R1C1C1008514,2019R1A6A1A11053838,and NRF-2023R1A2C1004015)the“Regional Innovation Strategy(RIS)”through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(MOE)(No.2021RIS-003).
文摘The visible-light-driven hydrogen evolution is extremely important,but the poor charge transfer capa-bility,a sluggish evolution rate of hydrogen,and severe photo-corrosion make photocatalytic hydrogen evolution impractical.In this study,we present 1D/2D ReS_(2)-CdS hybrid nanorods for photocatalytic hy-drogen evolution,comprised of a ReS_(2)nanosheet layer grown on CdS nanorods.We found that precise control of the contents of the ReS_(2)nanosheet layer allows for manipulating the electronic structure of Re in the ReS_(2)-CdS hybrid nanorods.The ReS_(2)-CdS hybrid nanorods with optimal ReS_(2)nanosheet layer content dramatically improve photocatalytic hydrogen evolution activity.Notably,photocatalytic hydro-gen evolution activity(64.93 mmol g^(−1)h^(−1))of ReS_(2)-CdS hybrid nanorods with ReS_(2)nanosheet layers(Re/Cd atomic ratio of 0.051)is approximately 136 times higher than that of pure CdS nanorods under visible light irradiation.Furthermore,intimated coupling of the ReS_(2)nanosheet layer with CdS nanorods reduced the surface trap-site of the CdS nanorods,resulting in enhanced photocatalytic stability.The de-tailed optical and electrical investigations demonstrate that the optimal ReS_(2)nanosheet layer contents in the ReS_(2)-CdS hybrid nanorods can provide improved charge transfer capability,catalytic activity,and light absorption efficiency.This study sheds light on the development of photocatalysts for highly efficient photocatalytic hydrogen evolution.
基金Project supported by the Science and Technology Commission of Shanghai Municipality(Grant No.09530708600)the Shanghai AM Foundation(Grant No.09700714000)
文摘The paper puts forward a method on controlling the AM-OLED panel to display image with high gray scale levels. It also gives an ASIC design sample to implement this method. A twenty sub-fields scan scheme has been taken into use in the chip to display 256 gray scale levels on a QVGA resolution AM-OLED display screen. The functions of image scaling and rotating have also been implemented for multiply application. The simulation and chip test result show that the chip design has met the design requirements.
基金funded by a grant from the National Institute of Child and Human Development(1R15HD071514-01A1)
文摘Background: Although emerging research is demonstrating the potential health impact of exergaming,investigations have primarily been conducted in laboratory settings among small samples with short-term interventions.Information on the effectiveness of exergaming in underserved children's objective physical activity(PA) in population-based settings is also scarce.Moreover,most empirical studies have only included 1 type of exergame in the intervention.Therefore,this study's purpose was to investigate the long-term impact of a multigame exergaming intervention among underserved children integrated within school curricula.Specifically,this study examined the effect of exergaming on children's accelerometer-determined sedentary behavior(SB),light PA,moderate-to-vigorous PA(MVPA),and energy expenditure(EE) over 2 years as compared with regular physical education(PE) classes.Methods: A total of 261 second-and third-grade children(134 girls,127 boys; mean age 8.27 years) were recruited from 2 Texas elementary schools.Children's pre-test 3-day SB,light PA,MVPA,and EE at school were assessed in the fall of 2012.Participants were assigned to 1 of 2groups:(1) exergaming/PE group(125 min weekly of exergaming-based PA program) and (2) comparison group(125 min weekly of PE).PA(SB,light PA,and MVPA) and EE outcome variables were assessed again in 2013(post-test) and 2014(follow-up).Results: Significant time effects were observed for SB(F(1,162)=25.0,p<0.01,η~2= 0.14),light PA(F(1,162)=9.6,p<0.01,η~2= 0.06),and MVPA(F(1,162)=6.2,p=0.01,η~2= 0.04) but not for EE(F(1,162)=0.63,p>0.05,η~2= 0.004).Subsequent pairwise comparisons revealed significant increases from pre-to post-test for light PA(p<0.01),MVPA(p<0.01),and EE(p=0.02) with no changes in SB(p>0.05).Conversely,significant decreases occurred in light PA(p<0.01) from post-test to follow-up with no differences seen in MVPA(p=0.08) and EE(p=0.06) over the same time period.A significant increase was seen,however,for SB from post-test to follow-up.Conclusion: Exergaming PE can have the same positive effect on children's light PA,MVPA,and EE as regular PE.More research is necessary to discern how to promote long-term PA participation after conclusion of the intervention.
基金supported in part by the Guangdong Universities and Major Scientific Projects(2017GWQNCX032).
文摘Numerous studies links movement activity(e.g.,physical activity,sedentary behavior[SB],and sleep)with mental health or illness indicators during the COVID-19 pandemic;however,research has typically examined time-use behaviors independently,rather than considering daily activity as a 24-hour time-use composition.This cross-sec-tional study aimed to use compositional isotemporal analysis to estimate the association between reallocation of time-use behaviors and depression symptoms in young adults in China.Participants(n=1475;68.0%of female;20.7[1.60]years)reported their time spent in moderate to vigorous physical activity(MVPA),light physical activ-ity(LPA),SB,and sleep.Replacing SB with sleep,LPA,and MVPA at 5,10,or 15 min was significantly associated with lower estimated depression symptoms scores.For example,adding MVPA from SB at 15 min was associated with lower depression symptoms scores(estimated difference:-0.13[-0.17,-0.09]).The associations between reallocation of time use behaviors with depression symptoms scores were slightly differentiated.Our results emphasize the importance of increased MVPA and decreased SB as well as their mutual replacements for lowering the risks of depression symptoms in young adults during the COVID-19 pandemic.Our results can inform policy to develop effective plans and strategies for mental health promotion.
基金supported by the National Natural Science Foundation of China(Nos.31871365 and 22177029)Fundamental Research Funds for the Central Universities.
文摘Protein S-sulfenylation(protein sulfenic acid),as one of the most significant oxidative post-translational modifications(OxiPTMs),plays a vital role in regulating protein function.A variety of activity-based probes have been developed to profile sulfenic acid in living cells.However,due to the transient presence and low content of sulfenic acid in living cell,high doses of probes are needed to achieve efficient labeling.More importantly,current probes have no temporal control over sulfenic acid labeling.To overcome these limitations,two caged cysteine sulfenic acid probes DYn-2-ONB and DYn-2-Cou with either an o-nitrobenzyl or coumarin protecting group were developed in this study.Both probes can be efficiently uncaged via irradiation to produce the active C-nucleophile probe DYn-2.Labeling assay in living cells demonstrated DYn-2-ONB exhibited better labeling capacity compared with DYn-2,providing it as a powerful tool for improved monitoring of protein S-sulfenylation in living cells.
文摘W, N co-doped TiO2 nanoparticles were synthesized by a sol-gel method. The prepared samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), trans- mission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-1R), X-ray photoelectron spectroscopy (XPS) and diffuse reflectance spectrophotometry (DRS). The results showed that the co- doped photocatalysts were essentially uniform spherical particles with the smallest particle size of 22.5 nm. Compared to un-doped TiO2, N-TiO2 and P-25, the absorption edge of the W, N co-doped TiO2 shifted to longer wavelength and its photocatalytic activity for degradation of methyl orange (MO) under Xe-lamp (350W) was higher.
基金financially supported by the National Natural Science Foundation of China (Nos. 50874025, 51090384)
文摘The photocatalytic degradation of methylene blue(MB) over Fe-doped CaTiO3 under UV-visible light was investigated. The as-prepared samples were characterized using X-ray diffraction(XRD), scanning electron microscope(SEM) equipped with an energy dispersive spectrometer(EDS) system, Fourier transform infrared spectra(FT-IR), and UV-visible diffuse reflectance spectroscopy(DRS). The results show that the doping with Fe significantly promoted the light absorption ability of CaTiO3 in the visible light region. The Fe-doped CaTiO3 exhibited higher photocatalytic activity than CaTiO3 for the degradation of MB.However, the photocatalytic activity of the Fe-doped CaTiO3 was greatly influenced by the calcination temperature during the preparation process. The Fe-doped CaTiO3 prepared at500°C exhibited the best photocatalytic activity, with degradation of almost 100% MB(10 ppm)under UV-visible light for 180 min.
基金supported by the Xinjiang Science and Technology Project (No.2019D01C036)。
文摘A series of MoS_2/ZnO compound photocatalysts with different mass ratios were successfully prepared by hydrothermal method. The X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), scanning electron microscope(SEM) and UV-vis absorption were used to characterize the prepared MoS_2/ZnO photocatalysts. It was proved that the combination of Mo S2 and Zn O can increase the content of oxygen vacancies on surface of Zn O, thus improving the light absorption capacity in visible light region and reducing the band gap of Zn O. And the photocatalytic performance of Zn O was improved. Experimental results show that the MoS_2/ZnO(3 wt%) compound has the highest degradation rate for methylene blue(MB) under visible light, which means that it has the best photocatalytic activity among all the prepared samples.
基金financially supported by the National Natural Science Foundation of China (Nos.21676113,21772054)Distinguished Young Scholar of Hubei Province (No.2018CFA079)+4 种基金the 111 Project (No.B17019)Scholar Support Program of CCNU (No.0900-31101090002)the Research Fund Program of Guangdong Key Laboratory of Radioactive and Rare Resource Utilization (No.2018B030322009)supported by Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules (No.KLSAOFM2012)Hubei University,China,Excellent Doctorial Dissertation Cultivation Grant of CCNU from the Colleges’ Basic Research and Operation of MOE (No.2019YBZZ029)。
文摘The photoisomerization properties of azo derivatives have been widely used in the fields of materials and biology.One serious restriction to the development of functional azo-based materials is the necessity to trigger switching by UV light,which damage the corresponding surfaces and penetrate only partially through the matter.Therefore,developing the visible and near-infrared light activated azo switches can solve this problem.This review provides a summary of molecular design strategies for driving the isomerization of azo derivatives with visible light and near-infrared light:(1) smart design directly excited by visible light,(2) the addition of upconversion nanoparticles,(3) the employment of twophoton absorption,(4) indirect excitation in combination with metal sensitizer.
基金supported by the National High Technology Research and Development Program (863 program, 2006AA06Z323)National Key Technology R&D Program (2008BAC32B06-3) of Chinaspecial fund of State Key Laboratory of Water Environment Simulation (08ESPCT-Z)
文摘Density functional theory (DFT) plays a significant role in the development of visible light responsive photocatalysts. Based on the first-principles plane-wave ultrasoft pseudopotential (USPP) method, the crystal structures of α,β,γ, and 5-Bi2O3 were optimally calculated for the total density of states (TDOS) and the partial density of states (PDOS) of Bi, O atoms. The calculation for Ti(IV) doped Bi2O3 supercell was carried out. The effects of Ti(IV)-doping on the electron structures and light absorption properties of various Bi2O3 were analyzed. The results showed that Ti 3d orbital appeared in the forbidden band of Bi2O3 and hybridized with O 2p, Bi 6p orbitals. The narrowed band gap (Eg) and red-shift of light absorption edge are responsible for the enhanced photoeatalytic activity of Bi2O3. The Ⅱ-Bi2O3 and Ti-doped β-Bi2O3 were prepared by a hydrotherrnal synthesis method. The improvement of the photoeatalytic activity of Bi2O3 has also been verified by the characteristics of the UV-vis diffuse reflection spectrum and the experimental evaluation of the photocatalytic degradation of crystal violet in aqueous solution.
基金supports of this work by KFUPM through the project # R15-CW-11 (MIT-13103, 13104) under the Center of Excellence for Scientific Research Collaboration with MIT and the project # RG 1311
文摘Polymeric-inorganic nanocomposite catalysts were synthesized by facile one-pot chemical polymerization of pyrrole in the presence of titanium dioxide nanoparticles. The electrical, optical, photovoltaic performance of dye sensitized solar cell(DSSC) and visible light driven photocatalytic activities of the nanocomposite were investigated. The prepared nanocomposite displays excellent photo-activity, attaining 100% degradation of methyl orange dye in 60 min under visible light source while 55% for pure TiO_2 under similar experimental conditions. The photovoltaic performance of the polypyrrole-titanium dioxide(PPy-TiO_2) nanocomposite has a 51.4% improvement with a photo-conversion efficiency of 8.07% as compared to pure TiO_2 based DSSC. By comparing the physical mixture of the PPy-TiO_2 nanocomposite and pristine TiO_2, the enhanced activity of the PPy-TiO_2 nanocomposite can be attributed to the reduced charge transfer resistance, outstanding electrical conductance of the PPy, the nano-sized structure of TiO_2 and their synergetic effect. Furthermore, the PPy-TiO_2 nanocomposite shows excellent electrical conductivity and isothermal stability under ambient conditions below 110?C.
文摘The chemical structure of newly synthesized cationic surfactants based on Schiff base was confirmed using Fourier transform infrared spectroscopy,proton nuclear magnetic resonance spectroscopy,and mass spectroscopy.The synthesized surfactants were used in the synthesis of silver nanoparticles by a simple one-step method.The silver nanoparticle(AgNPs) formation was confirmed using transmission electron microscopy(TEM),electron diffraction(SAED),dynamic light scattering(DLS),and energy dispersive X-ray spectroscopy(EDX).The structure of the surfactant played an important role in the synthesis process.Increasing the hydrophobic chain length,the stability,and the amount of surfactant increased the quantity of AgNPs formed.The surface activity of the synthesized cationic surfactants was determined using surface tension measurements at three different temperatures.The synthesized surfactants showed a high tendency toward adsorption and micellization.Increasing the hydrophobic chain length of the synthesized surfactant increased its adsorption.Screening the synthesized cationic surfactants and their nano-form against bacteria and fungi showed that they are highly effective.The silver nanoparticles enhanced the biological activity of the synthesized cationic surfactants.