Transition metal chalcogenides have nowadays garnered burgeoning interest owing to their fascinating electronic and catalytic properties,thus possessing great implications for energy conversion and storage application...Transition metal chalcogenides have nowadays garnered burgeoning interest owing to their fascinating electronic and catalytic properties,thus possessing great implications for energy conversion and storage applications.In this regard,their controllable synthesis in a large scale at low cost has readily become a focus of research.Herein we report diatomite-template generic and scalable production of VS2 and other transition metal sulfides targeting emerging energy conversion and storage applications.The conformal growth of VS2over diatomite template would endow them with defect-abundant features.Throughout detailed experimental investigation in combination with theoretical simulation,we reveal that the enriched active sites/sulfur vacancies of thus-derived VS2 architectures would pose positive impacts on the catalytic performance such in electrocatalytic hydrogen evolution reactions.We further show that the favorable electrical conductivity and highly exposed sites of VS2 hold promise for serving as sulfur host in the realm of Li-S batteries.Our work offers new insights into the templated and customized synthesis of defect-rich sulfides in a scalable fashion to benefit multifunctional energy applications.展开更多
Hydrogen peroxide (H_(2)O_(2)) is a valuable chemical for a wide variety of applications. The environmentally friendly production route of the electrochemical reduction of O_(2)to H_(2)O_(2) has become an attractive a...Hydrogen peroxide (H_(2)O_(2)) is a valuable chemical for a wide variety of applications. The environmentally friendly production route of the electrochemical reduction of O_(2)to H_(2)O_(2) has become an attractive alternative to the traditional anthraquinone process. The efficiency of electrosynthesis process depends considerably on the availability of cost-effective catalysts with high selectivity, activity, and stability.Currently, there are many outstanding issues in the preparation of highly selective catalysts, the exploration of the interface electrolysis environment, and the construction of electrolysis devices, which have led to extensive research efforts. Distinct from the existing few comprehensive review articles on H_(2)O_(2) production by two-electron oxygen reduction, the present review first explains the principle of the oxygen reduction reaction and then highlights recent advances in the regulation and control strategies of different types of catalysts. Key factors of electrode structure and device design are discussed. In addition,we highlight the promising co-production combination of this system with renewable energy or energy storage systems. This review can help introduce the potential of oxygen reduction electrochemical production of high-flux H_(2)O_(2) to the commercial market.展开更多
To understand the petrogenesis and magma evolution history in the Eastern Manus Basin(EMB),geochemistry of pyroxene and plagioclase mineral phenocrysts in basaltic andesites and dacites were reported.The plagioclase-m...To understand the petrogenesis and magma evolution history in the Eastern Manus Basin(EMB),geochemistry of pyroxene and plagioclase mineral phenocrysts in basaltic andesites and dacites were reported.The plagioclase-melt thermometry showed that,plagioclase in dacites crystalized in 1027.2–1028.5°C under 3.37–5.08 kbar,whereas in basaltic andesite was 1181.4–1187.0°C under 1.79–4.46 kbar.Pyroxene compositions and invariable La/Sm vs La values of whole rock powders indicate that lavas were erupted in rapid cooling rate and mainly controlled by fractional crystallization(FC).In addition,oscillatory zonings in plagioclase and pyroxene phenocrysts indicated small local perturbations and degassing episodes in the magma chamber.Some high Mg#clinopyroxene antecrysts were found in EMB lavas.The highest Mg#of parental EMB melts is 69,which falls into the range of initial partial melts from upper mantle peridotite source(68–75).In terms of isotopic compositions,the EMB lavas most likely originated from Indian-type MORB mantle which was infl uenced by subduction components.In details,the subduction components are mainly derived from the dehydration of a subducted altered oceanic crust,and the contribution of sediment infl uence is minor.The Pb isotopic compositions and end member modeling further suggest that the source of subduction components is more likely from the Pacifi c Plate instead of the Solomon Plate.展开更多
Metal-organic frameworks are recognized as promising multifunctional materials,especially metal-organic framework-based photocatalysts,which are considered to be ideal photocatalytic materials.Herein,a new type of UiO...Metal-organic frameworks are recognized as promising multifunctional materials,especially metal-organic framework-based photocatalysts,which are considered to be ideal photocatalytic materials.Herein,a new type of UiO-66/MoSe_(2) composite was prepared using the solvothermal method.The optimum composite was selected by adjusting the mass ratio of UiO-66 and MoSe_(2).X-ray diffraction analysis showed that the mass ratio influenced the crystal plane exposure rate of the composite,which may have affected its photocatalytic performance.The composite is composed of ultra-thin flower-like MoSe_(2) that wrapped around cubic UiO-66,a structure that increases the abundance of active sites for reactions and is more conducive to the separation of carriers.The photocatalytic properties of the composite were evaluated by measuring the degradation rate of Rhodamine B and the catalyst’s ability to reduce Cr(VI)-containing wastewater under visible light irradiation.Rhodamine B was decolorized completely in 120 min,and most of the Cr(VI)was reduced within 150 min.The photochemical mechanism of the complex was studied in detail.The existence of Mo^(6+)and oxygen vacancies,in addition to the Z-type heterojunction promote the separation of electrons and holes,which enhances the photocatalytic effect.展开更多
By using a two-step hydrothermal method and trithiocyanuric acid(TTCA),2,4,6-trihydrazino-1,3,5-triazine(THT),and Fe_(3)O_(4)as raw materials,a spherical magnetic adsorbent polymer(TTCA/THT@Fe_(3)O_(4))was synthesized...By using a two-step hydrothermal method and trithiocyanuric acid(TTCA),2,4,6-trihydrazino-1,3,5-triazine(THT),and Fe_(3)O_(4)as raw materials,a spherical magnetic adsorbent polymer(TTCA/THT@Fe_(3)O_(4))was synthesized to achieve the efficient removal of Cr(VI)from wastewater.Under optimal adsorption conditions,the maximum adsorption capacity of TTCA/THT@Fe_(3)O_(4)for Cr(VI)can reach 1340 mg∙g‒1.Notably,the removal efficiency can approach 98.9%,even at the lower concentration of 20 mg∙L^(‒1)Cr(VI).For actual wastewater containing Cr(VI),the Cr(VI)concentration was reduced from 25.8 to 0.4 mg∙L^(‒1),a remarkable 20%lower than the current industry discharge standard value.A mechanism for the high adsorption performance of Cr(VI)on TTCA/THT@Fe_(3)O_(4)was investigated using Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,and density functional theory.It can be plausibly attributed to the formation of Cr/N and Cr/S coordination bonds.Additionally,surface electrostatic adsorption,reduction effects,and the spherical polymer structure increase the contact area with Cr(VI),maximizing adsorption.The synergistic effect of adsorption and reduction enhances the adsorption performance of TTCA/THT@Fe_(3)O_(4)for Cr(VI)and total chromium in water.The resultant polymer has a simple preparation process,excellent adsorption performance,easy magnetic separation,and promising application for actual wastewater.展开更多
The degradation of ofloxacin(OFX)in the aqueous solution by Fenton oxidation process was investigated in the present study.The optimum operating conditions for the degradation of OFX in our system was determined.More ...The degradation of ofloxacin(OFX)in the aqueous solution by Fenton oxidation process was investigated in the present study.The optimum operating conditions for the degradation of OFX in our system was determined.More importantly,the degradation pathways on a basis of the identification of transformation products during the degradation of OFX were proposed,which revealed that the initial degradation step could be associated with the decarboxylation at the quinolone moiety.Moreover,the detachment of the F element during the Fenton oxidation process has also been detected.Since the carboxylic group within OFX has been considered as an important bridge for binding quinolones with the DNA gyrase target,the decarboxylation process would offer insights into the reduction of antibacterial potentials.展开更多
The increase in occurrence and severity of cyanobacteria blooms is causing increasing concern;moreover,human and animal health is affected by the toxic effects of Microcystin-LR released into the water.In this paper,a...The increase in occurrence and severity of cyanobacteria blooms is causing increasing concern;moreover,human and animal health is affected by the toxic effects of Microcystin-LR released into the water.In this paper,a floating photocatalyst for the photocatalytic inactivation of the harmful algae Microcystis aeruginosa(M.aeruginosa)was prepared using a simple sol-gel method,i.e.,coating g-C_(3)N_(4) coupled with Bi-doped TiO_(2) on Al_(2)O_(3)-modified expanded perlite(CBTA for short).The impact of different molar ratios of Bi/Ti on CBTA was considered.The results indicated that Bi doping in TiO_(2) inhibited photogenerated electron-hole pair recombination.With 6 h of visible light illumination,75.9%of M.aeruginosa(initial concentration=2.7106 cells/L)and 83.7%of Microcystin-LR(initial concentration=100μg/L)could be removed with the addition of 2 g/L CBTA1%(i.e.,Bi/Ti molar ratio=1%).The key reactive oxygen species(ROSs)in the photocatalytic inactivation process are h+andOH.The induction of the Bi^(4+)/Bi^(3+)species by the incorporation of Bi could narrow the bandgap of TiO_(2),trap electrons,and enhance the stability of CBTA-1%in the solutions with coexisting environmental substances.展开更多
Efficient generation of singlet oxygen(1 O_(2)) by an excitonic ene rgy transfer process is highly desired on a semiconductor photocatalyst for selective oxidation of methyl phenyl sulfide(MPS).Herein,it is demonstrat...Efficient generation of singlet oxygen(1 O_(2)) by an excitonic ene rgy transfer process is highly desired on a semiconductor photocatalyst for selective oxidation of methyl phenyl sulfide(MPS).Herein,it is demonstrated that a large amount of 1 O_(2) is produced on pristine graphitic carbon nitride(CN) nanosheet compared with bismuth oxybromide(BiOBr) and comme rcial P25 titanium dioxide(TiO_(2)).This leads to a certain photoactivity of CN for MPS oxidation.The observed ~77% selectivity for CN depends on the competitive results of excitonic energy transfer for 1 O_(2) formation and charge carrier separation for superoxide radical(O_(2)·) production,which are based on the phosphorescence spectra and electron paramagnetic resonance signals,respectively.Moreover,ultrathin CN nanosheets are synthesized by thermal treatment with the cyanuric acid-melamine hydrogen bonded aggregates as precursors.It is confirmed that the amount of produced 1 O_(2) could be increased by decreasing the thickness of resultant CN nanosheets.The optimized ultrathin CN nanosheet(~4 nm) exhibits excellent photoactivity with high selectivity(~99%).It is suggested that the excitonic energy transfer for 1 O_(2) formation is close related to the intrinsic exciton binding energy and the two-dimensional quantum confinement effect.This work establishes a basic mechanistic understanding on the excitonic processes in CN,and develops a feasible route to design CN-based photocatalysts for efficient 1 O_(2) generation.展开更多
The graphic carbon nitride/polyaniline(g-C_(3)N_(4)/PANI)hybrid composites were successfully synthesized by a facile in situ polymerization process under ice water bath.The photocatalytic activities of the g-C_(3)N_(4...The graphic carbon nitride/polyaniline(g-C_(3)N_(4)/PANI)hybrid composites were successfully synthesized by a facile in situ polymerization process under ice water bath.The photocatalytic activities of the g-C_(3)N_(4)/PANI composites were evaluated by using oxytetracycline(OTC)as model pollutants.The optimal g-C_(3)N_(4)/PANI composite(5%PANI:the g-C_(3)N_(4)/PANI hybrid with 5 wt.%of PANI)showed an enhancement degradation rate of 5-fold compared to that of conventional g-C_(3)N_(4)under simulated-sunlight irradiation.In addition,the 5%PANI demonstrate significantly photocatalytic evolution H_(2)rate(163.2μmol/(g·hr))under the visible light irradiation.Furthermore,based on the results of optical performance and electrochemical testing,a possible mechanism was proposed,indicating that the incorporation of PANI into the traditional g-C_(3)N_(4)can effectively tune the electronic structures,improve the photo-generated electrons-holes separation and enhance extensive absorption of visible light.Such a g-C_(3)N_(4)/PANI hybrid nanocomposites could be envisaged to possess great potentials in practical wastewater treatment and water splitting.展开更多
In this study,novel iron-doped biochar(Fe-BC) was produced using a simple method,and it was used as an H_(2)O_(2)activator for tetracycline(TC) degradation.Generally,iron loading can improve the separation performance...In this study,novel iron-doped biochar(Fe-BC) was produced using a simple method,and it was used as an H_(2)O_(2)activator for tetracycline(TC) degradation.Generally,iron loading can improve the separation performance and reactivity of biochar(BC).In the Fe-BC/H_(2)O_(2)system,92% of the TC was removed within 30 min with the apparent rate constant(k_(obs)) of 0.155 min^(-1),which was 23.85 times that in the case of the BC/H_(2)O_(2)system(0.0065 min^(-1)).The effects of the H_(2)O_(2) and Fe-BC dosage,initial pH,and TC concentration on the TC removal were investigated.The radical quenching and electron paramagnetic resonance(EPR) measurements demonstrated that the removal of TC using the Fe-BC/H_(2)O_(2)process involved both radical(^(*)OH and O_(2)^(-)) and non-radical pathways(^(1)O_(2) and electron transfer).In addition,the performance of the catalyst was also affected by the persistent free radicals(PFRs) and defective sites on the catalyst.Moreover,the degradation pathways of TC were proposed according to the intermediate products detected by LC-MS and the ecotoxicity of intermediates was evaluated.Finally,the Fe-BC/H_(2)O_(2)showed high resistance to inorganic anions and natural organic matter in aquatic environments.Overall,Fe-BC is expected to be an economic and highly efficient heterogeneous Fenton catalyst for removing the organic contaminants in wastewater.展开更多
Facing the body's EEG(electroencephalograph, 0.5–100 Hz, 5–100 μV) and ECG's(electrocardiogram,〈 100 Hz, 0.01–5 mV) micro signal detection requirement, this paper develops a pervasive application micro sign...Facing the body's EEG(electroencephalograph, 0.5–100 Hz, 5–100 μV) and ECG's(electrocardiogram,〈 100 Hz, 0.01–5 mV) micro signal detection requirement, this paper develops a pervasive application micro signal detection ASIC chip with the chopping modulation/demodulation method. The chopper-stabilization circuit with the RRL(ripple reduction loop) circuit is to suppress the ripple voltage, which locates at the single-stage amplifier's outputting terminal. The single-stage chopping core's noise has been suppressed too, and it is beneficial for suppressing noises of post-circuit. The chopping core circuit uses the PFB(positive feedback loop) to increase the inputting resistance, and the NFB(negative feedback loop) to stabilize the 40 dB intermediate frequency gain. The cascaded switch-capacitor sample/hold circuit has been used for deleting spike noises caused by non-ideal MOS switches, and the VGA/BPF(voltage gain amplifier/band pass filter) circuit is used to tune the chopper system's gain/bandwidth digitally. Assisted with the designed novel dry-electrode, the real test result of the chopping amplifying circuit gives some critical parameters: 8.1 μW/channel, 0.8 μVrms(@band-widthD100 Hz), 4216–11220 times digitally tuning gain range, etc. The data capture system uses the NI CO's data capturing DAQmx interface,and the captured micro EEG/ECG's waves are real-time displayed with the PC-Labview. The proposed chopper system is a unified EEG/ECG signal's detection instrument and has a critical real application value.展开更多
Sepsis,defined as life-threatening organ failure caused by a dysregulated host response to severe infection,is a major cause of death among intensive care unit patients.Therapies targeting on immunomodulatory is a new...Sepsis,defined as life-threatening organ failure caused by a dysregulated host response to severe infection,is a major cause of death among intensive care unit patients.Therapies targeting on immunomodulatory is a new research field in sepsis treatment.B-and T-lymphocyte attenuator(BTLA)is an inhibitory costimulatory factor molecule of B and T lymphocytes.Studies have shown that elevated expression of BTLA in lymphocytes can reduce mortality in sepsis,but its regulatory compounds and the underlying mechanism remains to be elucidated.Here,we show that treatment with CP-673451 significantly decreases mortality of septic mouse.CP-673451 is a PDGFR kinase inhibitor which can promote the expression of BTLA,inhibit the release of chemokines such as CXCL13,and reduce first the chemotaxis of B cells to the peripheral blood and vital organs.CP-673451 also inhibits both the release of cytokines and chemokines such as IL-1β,IL-6,IL-10,TNF-α,CCL1,CCL2 and CCL7 and reduces both the chemotactic ability of T cells.This suggests that CP-673451 may prevent septic death by inhibiting lymphocyte chemotaxis and alleviating“cytokine storm”.In conclusion,our study provides a new therapeutic target and an effective compound for sepsis treatment.展开更多
基金financially supported by the National Natural Science Foundation of China(nos.51702225,21671059,51702218)Jiangsu Youth Science Foundation(no.BK20170336)Program for Changjiang Scholars and Innovative Research Team in University(IRT-17R36).
文摘Transition metal chalcogenides have nowadays garnered burgeoning interest owing to their fascinating electronic and catalytic properties,thus possessing great implications for energy conversion and storage applications.In this regard,their controllable synthesis in a large scale at low cost has readily become a focus of research.Herein we report diatomite-template generic and scalable production of VS2 and other transition metal sulfides targeting emerging energy conversion and storage applications.The conformal growth of VS2over diatomite template would endow them with defect-abundant features.Throughout detailed experimental investigation in combination with theoretical simulation,we reveal that the enriched active sites/sulfur vacancies of thus-derived VS2 architectures would pose positive impacts on the catalytic performance such in electrocatalytic hydrogen evolution reactions.We further show that the favorable electrical conductivity and highly exposed sites of VS2 hold promise for serving as sulfur host in the realm of Li-S batteries.Our work offers new insights into the templated and customized synthesis of defect-rich sulfides in a scalable fashion to benefit multifunctional energy applications.
基金supported by the National Natural Science Foundation of China (51702225, 22179089)。
文摘Hydrogen peroxide (H_(2)O_(2)) is a valuable chemical for a wide variety of applications. The environmentally friendly production route of the electrochemical reduction of O_(2)to H_(2)O_(2) has become an attractive alternative to the traditional anthraquinone process. The efficiency of electrosynthesis process depends considerably on the availability of cost-effective catalysts with high selectivity, activity, and stability.Currently, there are many outstanding issues in the preparation of highly selective catalysts, the exploration of the interface electrolysis environment, and the construction of electrolysis devices, which have led to extensive research efforts. Distinct from the existing few comprehensive review articles on H_(2)O_(2) production by two-electron oxygen reduction, the present review first explains the principle of the oxygen reduction reaction and then highlights recent advances in the regulation and control strategies of different types of catalysts. Key factors of electrode structure and device design are discussed. In addition,we highlight the promising co-production combination of this system with renewable energy or energy storage systems. This review can help introduce the potential of oxygen reduction electrochemical production of high-flux H_(2)O_(2) to the commercial market.
基金Supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Nos.XDB42020303,XDA11030302)the National Natural Science Foundation of China(No.41576055)the National Basic Research Program of China(973 Program)(No.2013CB429702)。
文摘To understand the petrogenesis and magma evolution history in the Eastern Manus Basin(EMB),geochemistry of pyroxene and plagioclase mineral phenocrysts in basaltic andesites and dacites were reported.The plagioclase-melt thermometry showed that,plagioclase in dacites crystalized in 1027.2–1028.5°C under 3.37–5.08 kbar,whereas in basaltic andesite was 1181.4–1187.0°C under 1.79–4.46 kbar.Pyroxene compositions and invariable La/Sm vs La values of whole rock powders indicate that lavas were erupted in rapid cooling rate and mainly controlled by fractional crystallization(FC).In addition,oscillatory zonings in plagioclase and pyroxene phenocrysts indicated small local perturbations and degassing episodes in the magma chamber.Some high Mg#clinopyroxene antecrysts were found in EMB lavas.The highest Mg#of parental EMB melts is 69,which falls into the range of initial partial melts from upper mantle peridotite source(68–75).In terms of isotopic compositions,the EMB lavas most likely originated from Indian-type MORB mantle which was infl uenced by subduction components.In details,the subduction components are mainly derived from the dehydration of a subducted altered oceanic crust,and the contribution of sediment infl uence is minor.The Pb isotopic compositions and end member modeling further suggest that the source of subduction components is more likely from the Pacifi c Plate instead of the Solomon Plate.
基金supported by the National Natural Science Foundation of China (Grants Nos.22076039,and 22176051)Natural Science Foundation of Henan Province (Grant No.222300420054)excellent Science and Technology Innovation Team of Henan Normal University (Grant No.2021TD03).
文摘Metal-organic frameworks are recognized as promising multifunctional materials,especially metal-organic framework-based photocatalysts,which are considered to be ideal photocatalytic materials.Herein,a new type of UiO-66/MoSe_(2) composite was prepared using the solvothermal method.The optimum composite was selected by adjusting the mass ratio of UiO-66 and MoSe_(2).X-ray diffraction analysis showed that the mass ratio influenced the crystal plane exposure rate of the composite,which may have affected its photocatalytic performance.The composite is composed of ultra-thin flower-like MoSe_(2) that wrapped around cubic UiO-66,a structure that increases the abundance of active sites for reactions and is more conducive to the separation of carriers.The photocatalytic properties of the composite were evaluated by measuring the degradation rate of Rhodamine B and the catalyst’s ability to reduce Cr(VI)-containing wastewater under visible light irradiation.Rhodamine B was decolorized completely in 120 min,and most of the Cr(VI)was reduced within 150 min.The photochemical mechanism of the complex was studied in detail.The existence of Mo^(6+)and oxygen vacancies,in addition to the Z-type heterojunction promote the separation of electrons and holes,which enhances the photocatalytic effect.
基金supported by the National Natural Science Foundation of China(Grant Nos.22076039 and 22176051)Science Foundation for Outstanding Youth of Henan Province(Grant No.222300420054)Excellent Science and Technology Innovation Team of Henan Normal University(Grant No.2021TD03).
文摘By using a two-step hydrothermal method and trithiocyanuric acid(TTCA),2,4,6-trihydrazino-1,3,5-triazine(THT),and Fe_(3)O_(4)as raw materials,a spherical magnetic adsorbent polymer(TTCA/THT@Fe_(3)O_(4))was synthesized to achieve the efficient removal of Cr(VI)from wastewater.Under optimal adsorption conditions,the maximum adsorption capacity of TTCA/THT@Fe_(3)O_(4)for Cr(VI)can reach 1340 mg∙g‒1.Notably,the removal efficiency can approach 98.9%,even at the lower concentration of 20 mg∙L^(‒1)Cr(VI).For actual wastewater containing Cr(VI),the Cr(VI)concentration was reduced from 25.8 to 0.4 mg∙L^(‒1),a remarkable 20%lower than the current industry discharge standard value.A mechanism for the high adsorption performance of Cr(VI)on TTCA/THT@Fe_(3)O_(4)was investigated using Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,and density functional theory.It can be plausibly attributed to the formation of Cr/N and Cr/S coordination bonds.Additionally,surface electrostatic adsorption,reduction effects,and the spherical polymer structure increase the contact area with Cr(VI),maximizing adsorption.The synergistic effect of adsorption and reduction enhances the adsorption performance of TTCA/THT@Fe_(3)O_(4)for Cr(VI)and total chromium in water.The resultant polymer has a simple preparation process,excellent adsorption performance,easy magnetic separation,and promising application for actual wastewater.
基金supported by the Foundation and Advanced Technology Research Program of Henan Province (102300410098,0611020900,102300410193,and 122300410286)the Innovation Scientists and Technicians Troop Construction Projects of Henan Provincethe Plan for Scientific Innovation Talent of Henan Province
文摘The degradation of ofloxacin(OFX)in the aqueous solution by Fenton oxidation process was investigated in the present study.The optimum operating conditions for the degradation of OFX in our system was determined.More importantly,the degradation pathways on a basis of the identification of transformation products during the degradation of OFX were proposed,which revealed that the initial degradation step could be associated with the decarboxylation at the quinolone moiety.Moreover,the detachment of the F element during the Fenton oxidation process has also been detected.Since the carboxylic group within OFX has been considered as an important bridge for binding quinolones with the DNA gyrase target,the decarboxylation process would offer insights into the reduction of antibacterial potentials.
基金the support of this research by the National Natural Science Foundation of China(Grant Nos.22008057 and 51909165)financially supported by the PhD.Scientific Research Starting Foundation of Henan Normal University(No.5101219170135)ostdoctoral Research Foundation of Henan Normal University(No.5101219470222).
文摘The increase in occurrence and severity of cyanobacteria blooms is causing increasing concern;moreover,human and animal health is affected by the toxic effects of Microcystin-LR released into the water.In this paper,a floating photocatalyst for the photocatalytic inactivation of the harmful algae Microcystis aeruginosa(M.aeruginosa)was prepared using a simple sol-gel method,i.e.,coating g-C_(3)N_(4) coupled with Bi-doped TiO_(2) on Al_(2)O_(3)-modified expanded perlite(CBTA for short).The impact of different molar ratios of Bi/Ti on CBTA was considered.The results indicated that Bi doping in TiO_(2) inhibited photogenerated electron-hole pair recombination.With 6 h of visible light illumination,75.9%of M.aeruginosa(initial concentration=2.7106 cells/L)and 83.7%of Microcystin-LR(initial concentration=100μg/L)could be removed with the addition of 2 g/L CBTA1%(i.e.,Bi/Ti molar ratio=1%).The key reactive oxygen species(ROSs)in the photocatalytic inactivation process are h+andOH.The induction of the Bi^(4+)/Bi^(3+)species by the incorporation of Bi could narrow the bandgap of TiO_(2),trap electrons,and enhance the stability of CBTA-1%in the solutions with coexisting environmental substances.
基金NSFC(Nos.U1805255,11804086,21706044,21971057)General Financial Grant from the China Postdoctoral Science Foundation(No.2017M621316)+2 种基金the Natural Science Foundation of Heilongjiang Province,China(No.B2017006)the General Financial Grant from the Postdoctoral Science Foundation of Heilongjiang Province,China(No.LBHZ17187)the General Financial Grant from Heilongjiang Province for returned students from overseas in 2018。
文摘Efficient generation of singlet oxygen(1 O_(2)) by an excitonic ene rgy transfer process is highly desired on a semiconductor photocatalyst for selective oxidation of methyl phenyl sulfide(MPS).Herein,it is demonstrated that a large amount of 1 O_(2) is produced on pristine graphitic carbon nitride(CN) nanosheet compared with bismuth oxybromide(BiOBr) and comme rcial P25 titanium dioxide(TiO_(2)).This leads to a certain photoactivity of CN for MPS oxidation.The observed ~77% selectivity for CN depends on the competitive results of excitonic energy transfer for 1 O_(2) formation and charge carrier separation for superoxide radical(O_(2)·) production,which are based on the phosphorescence spectra and electron paramagnetic resonance signals,respectively.Moreover,ultrathin CN nanosheets are synthesized by thermal treatment with the cyanuric acid-melamine hydrogen bonded aggregates as precursors.It is confirmed that the amount of produced 1 O_(2) could be increased by decreasing the thickness of resultant CN nanosheets.The optimized ultrathin CN nanosheet(~4 nm) exhibits excellent photoactivity with high selectivity(~99%).It is suggested that the excitonic energy transfer for 1 O_(2) formation is close related to the intrinsic exciton binding energy and the two-dimensional quantum confinement effect.This work establishes a basic mechanistic understanding on the excitonic processes in CN,and develops a feasible route to design CN-based photocatalysts for efficient 1 O_(2) generation.
基金supported by the NSFC(Nos.21677047 and U1604137)the Innovation Scientists and Technicians Troop Construction Projects,the Research Start-up Foundation(No.5101219170107)+3 种基金the Youth Science Foundation(No.2015QK29)of Henan Normal University for the Ph Dthe Key Scientific and Technological Projects in Henan Province(No.132102210129)research fund from Henan Normal University(Nos.5101039170157 and 5101039170304)Postdoctoral Science Foundation of Henan Province(No.5201029470213)。
文摘The graphic carbon nitride/polyaniline(g-C_(3)N_(4)/PANI)hybrid composites were successfully synthesized by a facile in situ polymerization process under ice water bath.The photocatalytic activities of the g-C_(3)N_(4)/PANI composites were evaluated by using oxytetracycline(OTC)as model pollutants.The optimal g-C_(3)N_(4)/PANI composite(5%PANI:the g-C_(3)N_(4)/PANI hybrid with 5 wt.%of PANI)showed an enhancement degradation rate of 5-fold compared to that of conventional g-C_(3)N_(4)under simulated-sunlight irradiation.In addition,the 5%PANI demonstrate significantly photocatalytic evolution H_(2)rate(163.2μmol/(g·hr))under the visible light irradiation.Furthermore,based on the results of optical performance and electrochemical testing,a possible mechanism was proposed,indicating that the incorporation of PANI into the traditional g-C_(3)N_(4)can effectively tune the electronic structures,improve the photo-generated electrons-holes separation and enhance extensive absorption of visible light.Such a g-C_(3)N_(4)/PANI hybrid nanocomposites could be envisaged to possess great potentials in practical wastewater treatment and water splitting.
基金supported by National Natural Science Foundation of China (No. 21906045)The 2020 Scientific Research Project for Postgraduates of Henan Normal University (No. YL202029)。
文摘In this study,novel iron-doped biochar(Fe-BC) was produced using a simple method,and it was used as an H_(2)O_(2)activator for tetracycline(TC) degradation.Generally,iron loading can improve the separation performance and reactivity of biochar(BC).In the Fe-BC/H_(2)O_(2)system,92% of the TC was removed within 30 min with the apparent rate constant(k_(obs)) of 0.155 min^(-1),which was 23.85 times that in the case of the BC/H_(2)O_(2)system(0.0065 min^(-1)).The effects of the H_(2)O_(2) and Fe-BC dosage,initial pH,and TC concentration on the TC removal were investigated.The radical quenching and electron paramagnetic resonance(EPR) measurements demonstrated that the removal of TC using the Fe-BC/H_(2)O_(2)process involved both radical(^(*)OH and O_(2)^(-)) and non-radical pathways(^(1)O_(2) and electron transfer).In addition,the performance of the catalyst was also affected by the persistent free radicals(PFRs) and defective sites on the catalyst.Moreover,the degradation pathways of TC were proposed according to the intermediate products detected by LC-MS and the ecotoxicity of intermediates was evaluated.Finally,the Fe-BC/H_(2)O_(2)showed high resistance to inorganic anions and natural organic matter in aquatic environments.Overall,Fe-BC is expected to be an economic and highly efficient heterogeneous Fenton catalyst for removing the organic contaminants in wastewater.
基金Project supported by the National Natural Science Foundation of China(Nos.61527815,31500800,61501426,61471342)the National Key Basic Research Plan(No.2014CB744600)+1 种基金the Beijing Science and Technology Plan(No.Z141100000214002)the Chinese Academy of Sciences’Key Project(No.KJZD-EW-L11-2)
文摘Facing the body's EEG(electroencephalograph, 0.5–100 Hz, 5–100 μV) and ECG's(electrocardiogram,〈 100 Hz, 0.01–5 mV) micro signal detection requirement, this paper develops a pervasive application micro signal detection ASIC chip with the chopping modulation/demodulation method. The chopper-stabilization circuit with the RRL(ripple reduction loop) circuit is to suppress the ripple voltage, which locates at the single-stage amplifier's outputting terminal. The single-stage chopping core's noise has been suppressed too, and it is beneficial for suppressing noises of post-circuit. The chopping core circuit uses the PFB(positive feedback loop) to increase the inputting resistance, and the NFB(negative feedback loop) to stabilize the 40 dB intermediate frequency gain. The cascaded switch-capacitor sample/hold circuit has been used for deleting spike noises caused by non-ideal MOS switches, and the VGA/BPF(voltage gain amplifier/band pass filter) circuit is used to tune the chopper system's gain/bandwidth digitally. Assisted with the designed novel dry-electrode, the real test result of the chopping amplifying circuit gives some critical parameters: 8.1 μW/channel, 0.8 μVrms(@band-widthD100 Hz), 4216–11220 times digitally tuning gain range, etc. The data capture system uses the NI CO's data capturing DAQmx interface,and the captured micro EEG/ECG's waves are real-time displayed with the PC-Labview. The proposed chopper system is a unified EEG/ECG signal's detection instrument and has a critical real application value.
基金supported by the National Natural Science Foundation of China(82020108021)the Chongqing Special Project for Academicians(cstc2020yszx-jcyj X0004)+3 种基金the Project of the TraumaBurns and Combined Injury State Key Laboratory(SKLYQ201901,SKLKF201802)the Training Plan of the Innovation Ability of Military Medical Frontier Research(2019CXJSB014,2019CXJSB004)the Project of the Science and Technology Fund of Guizhou Provincial Department of Health(gzwjkj2020-1-106)。
文摘Sepsis,defined as life-threatening organ failure caused by a dysregulated host response to severe infection,is a major cause of death among intensive care unit patients.Therapies targeting on immunomodulatory is a new research field in sepsis treatment.B-and T-lymphocyte attenuator(BTLA)is an inhibitory costimulatory factor molecule of B and T lymphocytes.Studies have shown that elevated expression of BTLA in lymphocytes can reduce mortality in sepsis,but its regulatory compounds and the underlying mechanism remains to be elucidated.Here,we show that treatment with CP-673451 significantly decreases mortality of septic mouse.CP-673451 is a PDGFR kinase inhibitor which can promote the expression of BTLA,inhibit the release of chemokines such as CXCL13,and reduce first the chemotaxis of B cells to the peripheral blood and vital organs.CP-673451 also inhibits both the release of cytokines and chemokines such as IL-1β,IL-6,IL-10,TNF-α,CCL1,CCL2 and CCL7 and reduces both the chemotactic ability of T cells.This suggests that CP-673451 may prevent septic death by inhibiting lymphocyte chemotaxis and alleviating“cytokine storm”.In conclusion,our study provides a new therapeutic target and an effective compound for sepsis treatment.