Metal oxyhydroxides(MOOH)generated from irreversible reconstructions of transition metal compounds are intrinsic active species for oxygen evolution reaction,whose activities are still constrained by sluggish deproton...Metal oxyhydroxides(MOOH)generated from irreversible reconstructions of transition metal compounds are intrinsic active species for oxygen evolution reaction,whose activities are still constrained by sluggish deprotonation kinetics and inherent adsorption energy scaling relations.Herein,we construct a tunable proton acceptor(TPA)on oxyhydroxides by in-situ reconstruction of metal oxoacids such as NiC2O4to accelerate deprotonation and break adsorption energy scaling relations during OER.The modified C_(2)O_(4)^(2-)as a TPA can easily extract H of*OH(forming*HC2O4intermediate)and then promote deprotonation by the transmitted hydrogen bond with*OOH along conjugated(H...)O=C-O(-H)chain.As a result,Ni OOH-C2O4shows non-concerted proton-electron transfer and improved deprotonation rate,and delivers a good OER activity(270 mV@10 mA cm-2).The conjugate acidity coefficient(pKa)of the modified oxoacid group can be a descriptor for TPA selection.This TPA strategy can be universally applied to Co-,Fe-,and Ni-based oxyhydroxides to facilitate OER efficiency.展开更多
The Sixth-Generation(6G)standard for wireless communications is expected to realize ubiquitous coverage for massive Internet of Things(IoT)networks by 2030.Satellite-based communications are recognized as a highly pro...The Sixth-Generation(6G)standard for wireless communications is expected to realize ubiquitous coverage for massive Internet of Things(IoT)networks by 2030.Satellite-based communications are recognized as a highly promising technical enabler to satisfy IoT service requirements in the 6G era.This study analyzes multiple access technologies,which are essential for the effective deployment of satellite-based IoT.First,we thoroughly investigate the existing research related to massive access,including information-theory considerations as well as Non-Orthogonal Multiple Access(NOMA)and Random Access(RA)technologies.Then,we explore the influence of the satellite transmission environment on multiple access technologies.Based on this study,a Non-orthogonal Massive Grant-Free Access(NoMaGFA)scheme,which reaps the joint benefits of RA and NOMA,is proposed for asynchronous transmissions in satellite-based IoT to achieve improved system throughput and enhance the system robustness under varying traffics.Finally,we identify some important and interesting future developments for satellite-based IoT,including waveform design,transceiver design,resource allocation,and artificial intelligence-enhanced design.展开更多
Seahorses have evolved many unique biological traits,including a male brood pouch,the absence of caudal and pelvic fins,and the lack of spleen and gut-associated lymphatic tissue.The mitogenactivated protein kinases(M...Seahorses have evolved many unique biological traits,including a male brood pouch,the absence of caudal and pelvic fins,and the lack of spleen and gut-associated lymphatic tissue.The mitogenactivated protein kinases(MAPKs)are known to be involved in various important biological processes including growth,differentiation,immunity,and stress responses.Therefore,we hypothesized that the adaptive evolution and expression of the MAPK gene family in seahorse may differ from those of other teleost species.We identified positive selection sites in the erk2,erk5,jnk1,and p38αMAPK genes of the lined seahorse Hippocampus erectus and tiger-tailed seahorse Hippocampus comes.A novel expression profile of MAPK cascade genes was found in seahorse larvae during the first day after birth based on the RNA-seq data of H.erectus,which refl ected vital signs of immune response to its parental immune system.The expression patterns of the four positively selected MAPK genes were analyzed following the bacterial challenge of Vibrio fortis,revealing their upregulation pattern in brood pouch and other immune tissues.This study enriched our knowledge of the evolution of the H.erectus MAPK subfamilies,and could help better understanding the functional role of MAPKs in teleosts.展开更多
Electrocatalytic water splitting is limited by kinetics-sluggish oxygen evolution,in which the activity of catalysts depends on their electronic structure.However,the infl uence of electron spin polarization on cataly...Electrocatalytic water splitting is limited by kinetics-sluggish oxygen evolution,in which the activity of catalysts depends on their electronic structure.However,the infl uence of electron spin polarization on catalytic activity is ambiguous.Herein,we successfully regulate the spin polarization of Co_(3)O_(4)catalysts by tuning the concentration of cobalt defects from 0.8 to 14.5%.X-ray absorption spectroscopy spectra and density functional theory calculations confi rm that the spin polarization of Co_(3)O_(4)is positively correlated with the concentration of cobalt defects.Importantly,the enhanced spin polarization can increase hydroxyl group absorption to signifi cantly decrease the Gibbs free energy change value of the OER rate-determining step and regulate the spin polarization of oxygen species through a spin electron-exchange process to easily produce triplet-state O_(2),which can obviously increase electrocatalytic OER activity.In specifi c,Co_(3)O_(4)-50 with 14.5%cobalt defects exhibits the highest spin polarization and shows the best normalized OER activity.This work provides an important strategy to increase the water splitting activity of electrocatalysts via the rational regulation of electron spin polarization.展开更多
Spinel-type manganese-cobalt oxides have been regarded as important class of electrocatalysts for oxygen reduction reaction(ORR).However,they are usually synthesized through oxidation-precipitation under aqueous ammon...Spinel-type manganese-cobalt oxides have been regarded as important class of electrocatalysts for oxygen reduction reaction(ORR).However,they are usually synthesized through oxidation-precipitation under aqueous ammonia and then crystallization at high temperature(150–180℃),which not only increases the energy consumption but also induces the growth of particles that is unfavorable for ORR.Herein,through a facile precipitation-dehydration method,ultrasmall spinel manganese-cobalt oxide nanoparticles(~5 nm)homogeneously dispersed on conductive carbon black(MnxCo3-xO4/C)were fabricated at low temperature(60℃).And the bimetallic composite oxide(Mn1.5Co1.5O4/C)with cubic spinel structure and high Mn content exhibits remarkable enhancement of ORR activity and stability compared with single metal oxide(both Mn3O4/C and Co3O4/C).The essential reason for the enhancement of activity can be attributed to the presence of the mixed Mn^3+ and Mn^4+ cations in Mn1.5Co1.5O4/C.Moreover,the ORR activity of Mn1.5Co1.5O4/C is comparable to that of commercial 20 wt% Pt/C,and the relative current density only decreases 1.4% after 12 h test,exceeding that of Pt/C and most reported manganese-cobalt oxide electrocatalysts.展开更多
This paper presents a development process of software with Graphic User Interface (GUI) for monitoring temperature in a Zigbee Wireless Network. The software framework design was introduced and analyzed in detail. In ...This paper presents a development process of software with Graphic User Interface (GUI) for monitoring temperature in a Zigbee Wireless Network. The software framework design was introduced and analyzed in detail. In this paper, we wrote the software with C++ codes in Microsoft Foundation Class (MFC) programming of Visual C++ 6.0, which applied in wireless communication algorithms. Software test results show that temperature of Zibee network was real-time displayed by both text and curve, which achieved wireless temperature monitoring to Zigbee network.展开更多
This paper introduces a mobile phone short message control method in smart home based on GSM (Global System for Mobile communications). AT commands and the system structure is illustrated in detail. The hardware syste...This paper introduces a mobile phone short message control method in smart home based on GSM (Global System for Mobile communications). AT commands and the system structure is illustrated in detail. The hardware system including STC89C51 and TC35i is presented. The software framework is also analyzed clearly in this paper. In addition, some other potential application areas and its direction of development in future are given at last.展开更多
This paper presents a solution to wireless light control system based on Zigbee. Overall design framework of the system was introduced and analyzed in detail, which contained realization of hardware design. The Zigbee...This paper presents a solution to wireless light control system based on Zigbee. Overall design framework of the system was introduced and analyzed in detail, which contained realization of hardware design. The Zigbee wireless light control system was established based on CC2430-chip of Texas Instruments (TI). In this paper, we achieved designing Printed Circuit Board (PCB) for sensor nodes as end device and coordinator in Protel DXP 2004 and also wrote C codes in IAR embedded workbench development tool to form wireless network. Test results of system show that lights on end device or router in Zigbee wireless sensor networks (WSN) can be controlled by another switch on coordinator, which achieved remotely wireless intelligence light control.展开更多
Standardized Precipitation Index(SPI)and Standardized Precipitation Evapotranspiration Index(SPEI),traditionally derived at a monthly scale,are widely used drought indices.To overcome temporalresolution limitations,we...Standardized Precipitation Index(SPI)and Standardized Precipitation Evapotranspiration Index(SPEI),traditionally derived at a monthly scale,are widely used drought indices.To overcome temporalresolution limitations,we have previously developed and published a well-validated daily SPI/SPEI in situ dataset.Although having a high temporal resolution,this in situ dataset presents low spatial resolution due to the scarcity of stations.Therefore,based on the China Meteorological Forcing Dataset,which is composed of data from more than 1,000 ground-based observation sites and multiple remote sensing grid meteorological dataset,we present the first high spatiotemporal-resolution daily SPI/SPEI raster datasets over China.It spans from 1979 to 2018,with a spatial resolution of 0.1°×0.1°,a temporal resolution of 1-day,and the timescales of 30-,90-,and 360-days.Results show that the spatial distributions of drought event characteristics detected by the daily SPI/SPEI are consistent with the monthly SPI/SPEI.The correlation between the daily value of the 12-month scale and the monthly value of SPI/SPEI is the strongest,with linear correlation,Nash-Sutcliffe coefficient,and normalized root mean square error of 0.98,0.97,and 0.04,respectively.The daily SPI/SPEI is shown to be more sensitive to flash drought than the monthly SPI/SPEI.Our improved SPI/SPEI shows high accuracy and credibility,presenting enhanced results when compared to the monthly SPI/SPEI.The total data volume is up to 150 GB,compressed to 91 GB in Network Common Data Form(NetCDF).It can be available from Figshare(https://doi.org/10.6084/m9.figshare.c.5823533)and ScienceDB(https://doi.org/10.57760/sciencedb.j00076.00103).展开更多
Using an in situ lunar regolith as a construction material in combination with 3D printing not only reduces the weight of materials carried from the Earth but also improves the automation of lunar infrastructure const...Using an in situ lunar regolith as a construction material in combination with 3D printing not only reduces the weight of materials carried from the Earth but also improves the automation of lunar infrastructure construction.This study aims to improve the printability of a geopolymer based on a BH-1 lunar regolith simulant,including the extrudability,open time,and buildability,by controlling the temperature and adding admixtures.Rheological parameters were used to represent printability with different water-to-binder ratios,printing temperatures,and contents of additives.The mechanical properties of the hardening geopolymer with different filling paths and loading directions were tested.The results show that heating the printed filaments with a water-to-binder ratio of 0.32 at 80°C can adjust the printability without adding any additive,which can reduce the construction cost of lunar infrastructure.The printability of the BH-1 geopolymer can also be improved by adding 0.3%Attagel-50 and 0.5%polypropylene fiber by mass at a temperature of 20℃to cope with the changeable environmental conditions on the Moon.After curing under a simulated lunar environment,the 72-h flexural and compressive strengths of the geopolymer specimens reach 4.1 and 48.1 MPa,respectively,which are promising considering that the acceleration of gravity on the Moon is 1/6 of that on the Earth.展开更多
Oxygen defects play a critical role in the electrocatalytic oxygen evolution reaction(OER).Therefore,in-depth understanding the structure-activity-mechanism relationship of these defects is the key to design efficient...Oxygen defects play a critical role in the electrocatalytic oxygen evolution reaction(OER).Therefore,in-depth understanding the structure-activity-mechanism relationship of these defects is the key to design efficient OER electrocatalysts.This relationship needs to be understood dynamically due to the potential for irreversible phase transitions during OER.Consequently,significant efforts have been devoted to study the dynamic evolution of oxygen defects to shed light on the OER mechanism.This review critically examines and analyzes the dynamic processes occurring at oxygen defect sites during OER,including defect formation and defect evolution mechanisms,along with the advanced characterization techniques needed to understand these processes.This review aims to provide a comprehensive understanding of high-efficiency electrocatalysts,with a particular emphasis on the importance of in situ monitoring the dynamic evolution of oxygen defects,providing a new perspective towards efficient OER electrocatalyst design.展开更多
Cibotium barometz(Linn.)J.Sm.,a tree fern in the Dicksoniaceae family,is an economically important industrial exported plant in China and widely used in Traditional Chinese Medicine.C.barometz produces a range of bioa...Cibotium barometz(Linn.)J.Sm.,a tree fern in the Dicksoniaceae family,is an economically important industrial exported plant in China and widely used in Traditional Chinese Medicine.C.barometz produces a range of bioactive triterpenes and their metabolites.However,the biosynthetic pathway of triterpenes in C.barometz remains unknown.To clarify the origin of diverse triterpenes in C.barometz,we conducted de novo transcriptome sequencing and analysis of C.barometz rhizomes and leaves to identify the candidate genes involved in C.barometz triterpene biosynthesis.Three C.barometz triterpene synthases(CbTSs)candidate genes were obtained.All of them were highly expressed in C.barometz rhizomes,consisting of the accumulation pattern of triterpenes in C.barometz.To characterize the function of these CbTSs,we constructed a squalene-and oxidosqualene-overproducing yeast chassis by overexpressing all the enzymes in the MVA pathway under the control of GAL-regulated promoter and disrupted the GAL80 gene in Saccharomyces cerevisiae simultaneously.Heterologous expressing CbTS1,CbTS2,and CbTS3 in engineering yeast strain produced cycloartenol,dammaradiene,and diploptene,respectively.Phylogenetic analysis revealed that CbTS1 belongs to oxidosqualene cyclase,while CbTS2 and CbTS3 belong to squalene cyclase.These results decipher enzymatic mechanisms underlying the origin of diverse triterpene in C.barometz.展开更多
Synthetic biology relies on the screening and quantification of genetic components to assemble sophisticated gene circuits with specific functions.Microscopy is a powerful tool for characterizing complex cellular phen...Synthetic biology relies on the screening and quantification of genetic components to assemble sophisticated gene circuits with specific functions.Microscopy is a powerful tool for characterizing complex cellular phenotypes with increasing spatial and temporal resolution to library screening of genetic elements.Microscopy-based assays are powerful tools for characterizing cellular phenotypes with spatial and temporal resolution and can be applied to large-scale samples for library screening of genetic elements.However,strategies for high-throughput microscopy experiments remain limited.Here,we present a high-throughput,microscopy-based platform that can simultaneously complete the preparation of an 8×12-well agarose pad plate,allowing for the screening of 96 independent strains or experimental conditions in a single experiment.Using this platform,we screened a library of natural intrinsic promoters from Pseudomonas aeruginosa and identified a small subset of robust promoters that drives stable levels of gene expression under varying growth conditions.Additionally,the platform allowed for single-cell measurement of genetic elements over time,enabling the identification of complex and dynamic phenotypes to map genotype in high throughput.We expected that the platform could be employed to accelerate the identification and characterization of genetic elements in various biological systems,as well as to understand the relationship between cellular phenotypes and internal states,including genotypes and gene expression programs.展开更多
Dermatomyositis(DM)is a heterogeneous autoimmune disease associated with numerous myositis specific antibodies(MSAs)in which DM with anti-melanoma differentiation-associated gene 5-positive(MDA5+DM)is a unique subtype...Dermatomyositis(DM)is a heterogeneous autoimmune disease associated with numerous myositis specific antibodies(MSAs)in which DM with anti-melanoma differentiation-associated gene 5-positive(MDA5+DM)is a unique subtype of DM with higher risk of developing varying degrees of Interstitial lung disease(ILD).Glycosylation is a complex posttranslational modification of proteins associated with many autoimmune diseases.However,the association of total plasma N-glycome(TPNG)and DM,especially MDA5+DM,is still unknown.TPNG of 94 DM patients and 168 controls were analyzed by mass spectrometry with in-house reliable quantitative method called Bionic Glycome method.Logistic regression with age and sex adjusted was used to reveal the aberrant glycosylation of DM and the association of TPNG and MDA5+DM with or without rapidly progressive ILD(RPILD).The elastic net model was used to evaluate performance of glycans in distinguishing RPLID from non-RPILD,and survival analysis was analyzed with N-glycoslyation score by Kaplan-Meier survival analysis.It was found that the plasma protein N-glycome in DM showed higher fucosylation and bisection,lower sialylation(α2,3-notα2,6-linked)and galactosylation than controls.In MDA5+DM,more severe disease condition was associated with decreased sialylation(specificallyα2,3-sialylation with fucosylation)while accompanying elevated H6N5S3 and H5N4FSx,decreased galactosylation and increased fucosylation and the complexity of N-glycans.Moreover,glycosylation traits have better discrimination ability to distinguish RPILD from non-RPILD with AUC 0.922 than clinical features and is MDA5-independent.Survival advantage accrued to MDA5+DM with lower N-glycosylation score(p=3e-04).Our study reveals the aberrant glycosylation of DM for the first time and indicated that glycosylation is associated with disease severity caused by ILD in MDA5+DM,which might be considered as the potential biomarker for early diagnosis of RPILD and survival evaluation of MDA5+DM.展开更多
Gibberellins(GAs)are a class of plant hormones that can affect plant growth and development.GA-oxidases are rate-limiting enzymes,which play a direct role in GA accumulation in plants.However,the roles of GA-oxidase o...Gibberellins(GAs)are a class of plant hormones that can affect plant growth and development.GA-oxidases are rate-limiting enzymes,which play a direct role in GA accumulation in plants.However,the roles of GA-oxidase on carrot(Daucus carota L.)taproot development are still unclear.In this study,two GA-oxidase genes,DcGA20ox2 and DcGA2ox1,were identified in carrot.Transgenic carrot plants were obtained by using Agrobacterium-mediated genetic transformation method.The results showed that overexpression of DcGA20ox2 significantly promoted the accumulation of active GAs in carrot,increased plant height,generated more branches,and enhanced xylem development.Overexpression of DcGA2ox1 significantly reduced the total contents of active GAs compared with the control group,resulting in a dwarf phenotype and markedly increased lignin content of the transgenic carrot.The expression profiling showed that the genes of GA metabolic pathway responded to the negative feedback regulation mechanism.At the same time,the expression of most genes in lignin biosynthesis and polymerization process was up-regulated,corresponding to the massive accumulation of lignin.These findings indicated that DcGA20ox2 and DcGA2ox1affected carrot growth and development by regulating the levels of endogenous GAs.The results from current work might shed light on further studies aimed to regulate lignification in carrot and other crops.展开更多
Iron sulfide(FeS)nanoparticles(termed FSNs)have attracted much attention for the removal of pollutants due to their high efficiency and low cost,and because they are environmentally friendly.However,issues of agglomer...Iron sulfide(FeS)nanoparticles(termed FSNs)have attracted much attention for the removal of pollutants due to their high efficiency and low cost,and because they are environmentally friendly.However,issues of agglomeration,transformation,and the loss of active components limit their application.Therefore,this study investigates in situ synthesized FeS/carbon fibers with an Fecarrageenan biomass as a precursor and nontoxic sulfur source to ascertain the removal efficiency of the fibers.The enrichment of sulfate groups as well as the double-helix structure in i-carrageenan-Fe could effectively avoid the aggregation and loss of FSNs in practical applications.The obtained FeS/carbon fibers were used to control a Cr(Ⅵ)polluted solution,and exhibited a relatively high removal capacity(81.62 mg/g).T he main mechanisms included the reduction of FeS,electrostatic adsorption of carbon fibers,and Cr(Ⅲ)-Fe(Ⅲ)complexation reaction.The pseudo-second-order kinetic model and Langmuir adsorption model both provided a good fit of the reaction process;hence,the removal process was mainly controlled by chemical adsorption,specifically monolayer adsorption on a uniform surface.Furthermore,co-existing anions,column,and regeneration experiments indicated that the FeS/carbon fibers are a promising remediation material for practical application.展开更多
Modification is one of the most important and effective methods to improve the photoelectrocatalytic(PEC)performance of ZnO.In this paper,the Ru_(x)Zn_(1-x)O/Ti electrodes were prepared by thermal decomposition method...Modification is one of the most important and effective methods to improve the photoelectrocatalytic(PEC)performance of ZnO.In this paper,the Ru_(x)Zn_(1-x)O/Ti electrodes were prepared by thermal decomposition method and the effect of Ru content on those electrodes' electronic structure was analyzed through the first-principles calculation.Various tests were also performed to observe the microstructures and PEC performance.The results showed that as the Ru^(4+) transferred into ZnO lattice and replaced a number of Zn^(2+),the conduction band of ZnO moved downward and the valence band went upward.The number of photogenerated electron-hole pairs increased as the impurity levels appeared in the band gap.In addition,ZnO nanorods exhibited a smaller grain size and a rougher surface under the effect of Ru.Meanwhile,the RuO_(2) nanoparticles on the surface of ZnO nanorods acted as the electron-transfer channel,helping electrons transfer to the counter electrode and delaying the recombination of the electron-hole pairs.Specifically,the Ru_(x)Zn_(1-x)O/Ti electrodes with 9.375 mol% Ru exhibited the best PEC performance with a rhodamine B(RhB)removal rate of 97%,much higher than the combination of electrocatalysis(EC,12%)and photocatalysis(PC,50%),confirming the synergy of photoelectrocatalysis.展开更多
Safe and precise control of gas flow is one of the key factors to many physical and chemical processes,such as degassing,natural gas transportation,and gas sensor.In practical application,it is essential for the gas-i...Safe and precise control of gas flow is one of the key factors to many physical and chemical processes,such as degassing,natural gas transportation,and gas sensor.In practical application,it is essential for the gas-involved physicochemical process to keep everything under control and safe,which significantly relies on the controllability,safety,and stability of their valves.Here we show a light-responsive and corrosion-resistant gas valve with non-thermal effective liquid-gating positional flow control under a constant pressure by incorporating dynamic gating liquid with light responsiveness of solid porous substrate.Our experimental and theoretical analysis reveal that the photoisomerization of azobenzene-based molecular photoswitches on the porous substrate enabled the gas valve to possess a light-responsive and reversible variation of substantial critical pressure of non-thermal effective gas flow switch.Moreover,the chemically inert gating liquid prevented the solid substrate from corrosion and,by combining with the high spatiotemporal resolution of light,the gas valve realizes a precisely positional open and close under a steady-state pressure.The application demonstrations in our results show the potentials of the new gas valve for bringing opportunities to many applications,such as gas-involved reaction control in microfluidics,soft actuators,and beyond.展开更多
The ability of membrane technologies to dynamically tune the transport behavior for gases and liquids is critical for their applications.Although various methods have been developed to improve membrane success,tradeof...The ability of membrane technologies to dynamically tune the transport behavior for gases and liquids is critical for their applications.Although various methods have been developed to improve membrane success,tradeoffs still exist among their properties,such as permeability,selectivity,fouling resistance,and stability,which can greatly affect the performance of membranes.Existing elastomeric membrane designs can provide antifracture properties and flexibility;however,these designs still face certain challenges,such as low tensile strength and reliability.Additionally,researchers have not yet thoroughly developed membranes that can avoid fouling issues while realizing precise dynamic control over the transport substances.In this study,we show a versatile strategy for preparing graphene oxide-reinforced elastomeric liquid gating membranes that can finely modulate and dynamically tune the sorting of a wide range of gases and liquids under constant applied pressures.Moreover,the produced membranes exhibit antifouling properties and are adaptable to different length scales,pressures,and environments.The filling of graphene oxide in the thermoplastic polyurethane matrix enhances the composites through hydrogen bonds.Experiments and theoretical calculations are carried out to demonstrate the stability of our system.Our membrane exhibits good stretchability,recovery,and durability due to the elastic nature of the solid matrix and dynamic nature of the gating liquid.Dynamic control over the transport of gases and liquids is achieved through our optimized interfacial design and controllable pore deformation,which is induced by mechanical stimuli.Our strategy will create new opportunities for many applications,such as gas-involved chemical reactions,multiphase separation,microfluidics,multiphase microreactors,and particulate material synthesis.展开更多
基金the support from the National Key R&D Program of China(2020YFA0710000)the National Natural Science Foundation of China(22278307,22222808,21978200)the Haihe Laboratory of Sustainable Chemical Transformations。
文摘Metal oxyhydroxides(MOOH)generated from irreversible reconstructions of transition metal compounds are intrinsic active species for oxygen evolution reaction,whose activities are still constrained by sluggish deprotonation kinetics and inherent adsorption energy scaling relations.Herein,we construct a tunable proton acceptor(TPA)on oxyhydroxides by in-situ reconstruction of metal oxoacids such as NiC2O4to accelerate deprotonation and break adsorption energy scaling relations during OER.The modified C_(2)O_(4)^(2-)as a TPA can easily extract H of*OH(forming*HC2O4intermediate)and then promote deprotonation by the transmitted hydrogen bond with*OOH along conjugated(H...)O=C-O(-H)chain.As a result,Ni OOH-C2O4shows non-concerted proton-electron transfer and improved deprotonation rate,and delivers a good OER activity(270 mV@10 mA cm-2).The conjugate acidity coefficient(pKa)of the modified oxoacid group can be a descriptor for TPA selection.This TPA strategy can be universally applied to Co-,Fe-,and Ni-based oxyhydroxides to facilitate OER efficiency.
基金This work is supported in part by the NSF of China(no.61801064,no.92038302,no.62071038,no.61901035)Beijing Institute of Technology Research Fund Program for Young Scholars and Young Elite Scientist Sponsorship Program by CASTPart of the work of R.Zhang is also supported by Science and Technology Project of Beijing Municipal Education Commission(no.KM202010028005).
文摘The Sixth-Generation(6G)standard for wireless communications is expected to realize ubiquitous coverage for massive Internet of Things(IoT)networks by 2030.Satellite-based communications are recognized as a highly promising technical enabler to satisfy IoT service requirements in the 6G era.This study analyzes multiple access technologies,which are essential for the effective deployment of satellite-based IoT.First,we thoroughly investigate the existing research related to massive access,including information-theory considerations as well as Non-Orthogonal Multiple Access(NOMA)and Random Access(RA)technologies.Then,we explore the influence of the satellite transmission environment on multiple access technologies.Based on this study,a Non-orthogonal Massive Grant-Free Access(NoMaGFA)scheme,which reaps the joint benefits of RA and NOMA,is proposed for asynchronous transmissions in satellite-based IoT to achieve improved system throughput and enhance the system robustness under varying traffics.Finally,we identify some important and interesting future developments for satellite-based IoT,including waveform design,transceiver design,resource allocation,and artificial intelligence-enhanced design.
基金Supported by the Shandong Province Science and Technology Support Program for Outstanding Youth of Colleges and Universities(No.2020KJF007)the Shandong Province Science and Technology Research Program for Colleges and Universities(No.J18KA146)+3 种基金the Yantai Foundation for Development of Science and Technology(Nos.2020LJRC120,2019CXJJ040)the Weihai Foundation for Development of Science and Technology(No.2017GNS10)the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(No.GML2019ZD0407)the Guangdong Basic and Applied Basic Research Foundation(No.2019A1515110199)。
文摘Seahorses have evolved many unique biological traits,including a male brood pouch,the absence of caudal and pelvic fins,and the lack of spleen and gut-associated lymphatic tissue.The mitogenactivated protein kinases(MAPKs)are known to be involved in various important biological processes including growth,differentiation,immunity,and stress responses.Therefore,we hypothesized that the adaptive evolution and expression of the MAPK gene family in seahorse may differ from those of other teleost species.We identified positive selection sites in the erk2,erk5,jnk1,and p38αMAPK genes of the lined seahorse Hippocampus erectus and tiger-tailed seahorse Hippocampus comes.A novel expression profile of MAPK cascade genes was found in seahorse larvae during the first day after birth based on the RNA-seq data of H.erectus,which refl ected vital signs of immune response to its parental immune system.The expression patterns of the four positively selected MAPK genes were analyzed following the bacterial challenge of Vibrio fortis,revealing their upregulation pattern in brood pouch and other immune tissues.This study enriched our knowledge of the evolution of the H.erectus MAPK subfamilies,and could help better understanding the functional role of MAPKs in teleosts.
基金The authors appreciate the fi nancial support from the National Natural Science Foundation of China(Nos.21978200 and 22161142002)the Haihe Laboratory of Sustainable Chemical Transformations(CYZC202103).
文摘Electrocatalytic water splitting is limited by kinetics-sluggish oxygen evolution,in which the activity of catalysts depends on their electronic structure.However,the infl uence of electron spin polarization on catalytic activity is ambiguous.Herein,we successfully regulate the spin polarization of Co_(3)O_(4)catalysts by tuning the concentration of cobalt defects from 0.8 to 14.5%.X-ray absorption spectroscopy spectra and density functional theory calculations confi rm that the spin polarization of Co_(3)O_(4)is positively correlated with the concentration of cobalt defects.Importantly,the enhanced spin polarization can increase hydroxyl group absorption to signifi cantly decrease the Gibbs free energy change value of the OER rate-determining step and regulate the spin polarization of oxygen species through a spin electron-exchange process to easily produce triplet-state O_(2),which can obviously increase electrocatalytic OER activity.In specifi c,Co_(3)O_(4)-50 with 14.5%cobalt defects exhibits the highest spin polarization and shows the best normalized OER activity.This work provides an important strategy to increase the water splitting activity of electrocatalysts via the rational regulation of electron spin polarization.
文摘Spinel-type manganese-cobalt oxides have been regarded as important class of electrocatalysts for oxygen reduction reaction(ORR).However,they are usually synthesized through oxidation-precipitation under aqueous ammonia and then crystallization at high temperature(150–180℃),which not only increases the energy consumption but also induces the growth of particles that is unfavorable for ORR.Herein,through a facile precipitation-dehydration method,ultrasmall spinel manganese-cobalt oxide nanoparticles(~5 nm)homogeneously dispersed on conductive carbon black(MnxCo3-xO4/C)were fabricated at low temperature(60℃).And the bimetallic composite oxide(Mn1.5Co1.5O4/C)with cubic spinel structure and high Mn content exhibits remarkable enhancement of ORR activity and stability compared with single metal oxide(both Mn3O4/C and Co3O4/C).The essential reason for the enhancement of activity can be attributed to the presence of the mixed Mn^3+ and Mn^4+ cations in Mn1.5Co1.5O4/C.Moreover,the ORR activity of Mn1.5Co1.5O4/C is comparable to that of commercial 20 wt% Pt/C,and the relative current density only decreases 1.4% after 12 h test,exceeding that of Pt/C and most reported manganese-cobalt oxide electrocatalysts.
文摘This paper presents a development process of software with Graphic User Interface (GUI) for monitoring temperature in a Zigbee Wireless Network. The software framework design was introduced and analyzed in detail. In this paper, we wrote the software with C++ codes in Microsoft Foundation Class (MFC) programming of Visual C++ 6.0, which applied in wireless communication algorithms. Software test results show that temperature of Zibee network was real-time displayed by both text and curve, which achieved wireless temperature monitoring to Zigbee network.
文摘This paper introduces a mobile phone short message control method in smart home based on GSM (Global System for Mobile communications). AT commands and the system structure is illustrated in detail. The hardware system including STC89C51 and TC35i is presented. The software framework is also analyzed clearly in this paper. In addition, some other potential application areas and its direction of development in future are given at last.
文摘This paper presents a solution to wireless light control system based on Zigbee. Overall design framework of the system was introduced and analyzed in detail, which contained realization of hardware design. The Zigbee wireless light control system was established based on CC2430-chip of Texas Instruments (TI). In this paper, we achieved designing Printed Circuit Board (PCB) for sensor nodes as end device and coordinator in Protel DXP 2004 and also wrote C codes in IAR embedded workbench development tool to form wireless network. Test results of system show that lights on end device or router in Zigbee wireless sensor networks (WSN) can be controlled by another switch on coordinator, which achieved remotely wireless intelligence light control.
基金the China meteorological forcing dataset.Thanks to the Natural Science Foundation of Fujian Province(No.2021J01627,No.2020J01465)the National Natural Science Foundation of China(No.41601562,No.32071776)for their financial support.
文摘Standardized Precipitation Index(SPI)and Standardized Precipitation Evapotranspiration Index(SPEI),traditionally derived at a monthly scale,are widely used drought indices.To overcome temporalresolution limitations,we have previously developed and published a well-validated daily SPI/SPEI in situ dataset.Although having a high temporal resolution,this in situ dataset presents low spatial resolution due to the scarcity of stations.Therefore,based on the China Meteorological Forcing Dataset,which is composed of data from more than 1,000 ground-based observation sites and multiple remote sensing grid meteorological dataset,we present the first high spatiotemporal-resolution daily SPI/SPEI raster datasets over China.It spans from 1979 to 2018,with a spatial resolution of 0.1°×0.1°,a temporal resolution of 1-day,and the timescales of 30-,90-,and 360-days.Results show that the spatial distributions of drought event characteristics detected by the daily SPI/SPEI are consistent with the monthly SPI/SPEI.The correlation between the daily value of the 12-month scale and the monthly value of SPI/SPEI is the strongest,with linear correlation,Nash-Sutcliffe coefficient,and normalized root mean square error of 0.98,0.97,and 0.04,respectively.The daily SPI/SPEI is shown to be more sensitive to flash drought than the monthly SPI/SPEI.Our improved SPI/SPEI shows high accuracy and credibility,presenting enhanced results when compared to the monthly SPI/SPEI.The total data volume is up to 150 GB,compressed to 91 GB in Network Common Data Form(NetCDF).It can be available from Figshare(https://doi.org/10.6084/m9.figshare.c.5823533)and ScienceDB(https://doi.org/10.57760/sciencedb.j00076.00103).
基金supported by the National Natural Science Foundation of China(Grant Nos.42241128,51978029)Key Laboratory of Road and Traffic Engineering of the Ministry of Education,Tongji University(No.K202206)+1 种基金China Postdoctoral Science Foundation(No.2023M730174)Young Elite Scientist Sponsorship Program by Beijing Association for Science and Technology(No.BYESS2023418).
文摘Using an in situ lunar regolith as a construction material in combination with 3D printing not only reduces the weight of materials carried from the Earth but also improves the automation of lunar infrastructure construction.This study aims to improve the printability of a geopolymer based on a BH-1 lunar regolith simulant,including the extrudability,open time,and buildability,by controlling the temperature and adding admixtures.Rheological parameters were used to represent printability with different water-to-binder ratios,printing temperatures,and contents of additives.The mechanical properties of the hardening geopolymer with different filling paths and loading directions were tested.The results show that heating the printed filaments with a water-to-binder ratio of 0.32 at 80°C can adjust the printability without adding any additive,which can reduce the construction cost of lunar infrastructure.The printability of the BH-1 geopolymer can also be improved by adding 0.3%Attagel-50 and 0.5%polypropylene fiber by mass at a temperature of 20℃to cope with the changeable environmental conditions on the Moon.After curing under a simulated lunar environment,the 72-h flexural and compressive strengths of the geopolymer specimens reach 4.1 and 48.1 MPa,respectively,which are promising considering that the acceleration of gravity on the Moon is 1/6 of that on the Earth.
基金supported by the Ministry of Science and Technology(MOST)of China through the Key Project of Research&Development(2021YFF0500502)。
文摘Oxygen defects play a critical role in the electrocatalytic oxygen evolution reaction(OER).Therefore,in-depth understanding the structure-activity-mechanism relationship of these defects is the key to design efficient OER electrocatalysts.This relationship needs to be understood dynamically due to the potential for irreversible phase transitions during OER.Consequently,significant efforts have been devoted to study the dynamic evolution of oxygen defects to shed light on the OER mechanism.This review critically examines and analyzes the dynamic processes occurring at oxygen defect sites during OER,including defect formation and defect evolution mechanisms,along with the advanced characterization techniques needed to understand these processes.This review aims to provide a comprehensive understanding of high-efficiency electrocatalysts,with a particular emphasis on the importance of in situ monitoring the dynamic evolution of oxygen defects,providing a new perspective towards efficient OER electrocatalyst design.
基金the National Natural Science Foundation of China(No.81874333)the Key Laboratory of Guangdong Drug Administration(2021ZDB03)the Guangdong Basic and Applied Basic Research Foundation(No.2020B1515130005).
文摘Cibotium barometz(Linn.)J.Sm.,a tree fern in the Dicksoniaceae family,is an economically important industrial exported plant in China and widely used in Traditional Chinese Medicine.C.barometz produces a range of bioactive triterpenes and their metabolites.However,the biosynthetic pathway of triterpenes in C.barometz remains unknown.To clarify the origin of diverse triterpenes in C.barometz,we conducted de novo transcriptome sequencing and analysis of C.barometz rhizomes and leaves to identify the candidate genes involved in C.barometz triterpene biosynthesis.Three C.barometz triterpene synthases(CbTSs)candidate genes were obtained.All of them were highly expressed in C.barometz rhizomes,consisting of the accumulation pattern of triterpenes in C.barometz.To characterize the function of these CbTSs,we constructed a squalene-and oxidosqualene-overproducing yeast chassis by overexpressing all the enzymes in the MVA pathway under the control of GAL-regulated promoter and disrupted the GAL80 gene in Saccharomyces cerevisiae simultaneously.Heterologous expressing CbTS1,CbTS2,and CbTS3 in engineering yeast strain produced cycloartenol,dammaradiene,and diploptene,respectively.Phylogenetic analysis revealed that CbTS1 belongs to oxidosqualene cyclase,while CbTS2 and CbTS3 belong to squalene cyclase.These results decipher enzymatic mechanisms underlying the origin of diverse triterpene in C.barometz.
基金supported by the National Key Research and Development Program of China (Grant No.2020YFA0906900 to Fan Jin)the National Natural Science Foundation of China (Grant No.32000061 to Rongrong Zhang and 32101177 to Yajia Huang)Shenzhen Engineering Research Center of Therapeutic Synthetic Microbes (Grant No.XMHT20220104015 to Fan Jin)。
文摘Synthetic biology relies on the screening and quantification of genetic components to assemble sophisticated gene circuits with specific functions.Microscopy is a powerful tool for characterizing complex cellular phenotypes with increasing spatial and temporal resolution to library screening of genetic elements.Microscopy-based assays are powerful tools for characterizing cellular phenotypes with spatial and temporal resolution and can be applied to large-scale samples for library screening of genetic elements.However,strategies for high-throughput microscopy experiments remain limited.Here,we present a high-throughput,microscopy-based platform that can simultaneously complete the preparation of an 8×12-well agarose pad plate,allowing for the screening of 96 independent strains or experimental conditions in a single experiment.Using this platform,we screened a library of natural intrinsic promoters from Pseudomonas aeruginosa and identified a small subset of robust promoters that drives stable levels of gene expression under varying growth conditions.Additionally,the platform allowed for single-cell measurement of genetic elements over time,enabling the identification of complex and dynamic phenotypes to map genotype in high throughput.We expected that the platform could be employed to accelerate the identification and characterization of genetic elements in various biological systems,as well as to understand the relationship between cellular phenotypes and internal states,including genotypes and gene expression programs.
基金supported by grants from The National Key R&D Program of China(2022YFC3400803)the National Natural Science Foundation of China(32071276)+1 种基金Greater Bay Area Institute of Precision Medicine(IPM2021C005)National Postdoctoral Program for Innovative Talents(BX20190076).
文摘Dermatomyositis(DM)is a heterogeneous autoimmune disease associated with numerous myositis specific antibodies(MSAs)in which DM with anti-melanoma differentiation-associated gene 5-positive(MDA5+DM)is a unique subtype of DM with higher risk of developing varying degrees of Interstitial lung disease(ILD).Glycosylation is a complex posttranslational modification of proteins associated with many autoimmune diseases.However,the association of total plasma N-glycome(TPNG)and DM,especially MDA5+DM,is still unknown.TPNG of 94 DM patients and 168 controls were analyzed by mass spectrometry with in-house reliable quantitative method called Bionic Glycome method.Logistic regression with age and sex adjusted was used to reveal the aberrant glycosylation of DM and the association of TPNG and MDA5+DM with or without rapidly progressive ILD(RPILD).The elastic net model was used to evaluate performance of glycans in distinguishing RPLID from non-RPILD,and survival analysis was analyzed with N-glycoslyation score by Kaplan-Meier survival analysis.It was found that the plasma protein N-glycome in DM showed higher fucosylation and bisection,lower sialylation(α2,3-notα2,6-linked)and galactosylation than controls.In MDA5+DM,more severe disease condition was associated with decreased sialylation(specificallyα2,3-sialylation with fucosylation)while accompanying elevated H6N5S3 and H5N4FSx,decreased galactosylation and increased fucosylation and the complexity of N-glycans.Moreover,glycosylation traits have better discrimination ability to distinguish RPILD from non-RPILD with AUC 0.922 than clinical features and is MDA5-independent.Survival advantage accrued to MDA5+DM with lower N-glycosylation score(p=3e-04).Our study reveals the aberrant glycosylation of DM for the first time and indicated that glycosylation is associated with disease severity caused by ILD in MDA5+DM,which might be considered as the potential biomarker for early diagnosis of RPILD and survival evaluation of MDA5+DM.
基金supported by the National Natural Science Foundation of China(Grant Nos.3210236932372681)+1 种基金Natural Science Foundation of Jiangsu Province(BK20211366)the Priority Academic Program Development of Jiangsu Higher Education Institutions Project(PAPD)。
文摘Gibberellins(GAs)are a class of plant hormones that can affect plant growth and development.GA-oxidases are rate-limiting enzymes,which play a direct role in GA accumulation in plants.However,the roles of GA-oxidase on carrot(Daucus carota L.)taproot development are still unclear.In this study,two GA-oxidase genes,DcGA20ox2 and DcGA2ox1,were identified in carrot.Transgenic carrot plants were obtained by using Agrobacterium-mediated genetic transformation method.The results showed that overexpression of DcGA20ox2 significantly promoted the accumulation of active GAs in carrot,increased plant height,generated more branches,and enhanced xylem development.Overexpression of DcGA2ox1 significantly reduced the total contents of active GAs compared with the control group,resulting in a dwarf phenotype and markedly increased lignin content of the transgenic carrot.The expression profiling showed that the genes of GA metabolic pathway responded to the negative feedback regulation mechanism.At the same time,the expression of most genes in lignin biosynthesis and polymerization process was up-regulated,corresponding to the massive accumulation of lignin.These findings indicated that DcGA20ox2 and DcGA2ox1affected carrot growth and development by regulating the levels of endogenous GAs.The results from current work might shed light on further studies aimed to regulate lignification in carrot and other crops.
基金This research was funded by the National Natural Science Foundation of China(Grant Nos.51672143 and 51808303)Natural Science Foundation of Shandong Province(Nos.ZR2019BEE027 and ZR2018BEM002)+1 种基金Applied Basic Research of Qingdao City(Special Youth Project)(Nos.19-6-2-74-cg and 19-6-2-83-cg)Outstanding Youth of Natural Science in Shandong Province(No.JQ201713),and Taishan Scholars Program.
文摘Iron sulfide(FeS)nanoparticles(termed FSNs)have attracted much attention for the removal of pollutants due to their high efficiency and low cost,and because they are environmentally friendly.However,issues of agglomeration,transformation,and the loss of active components limit their application.Therefore,this study investigates in situ synthesized FeS/carbon fibers with an Fecarrageenan biomass as a precursor and nontoxic sulfur source to ascertain the removal efficiency of the fibers.The enrichment of sulfate groups as well as the double-helix structure in i-carrageenan-Fe could effectively avoid the aggregation and loss of FSNs in practical applications.The obtained FeS/carbon fibers were used to control a Cr(Ⅵ)polluted solution,and exhibited a relatively high removal capacity(81.62 mg/g).T he main mechanisms included the reduction of FeS,electrostatic adsorption of carbon fibers,and Cr(Ⅲ)-Fe(Ⅲ)complexation reaction.The pseudo-second-order kinetic model and Langmuir adsorption model both provided a good fit of the reaction process;hence,the removal process was mainly controlled by chemical adsorption,specifically monolayer adsorption on a uniform surface.Furthermore,co-existing anions,column,and regeneration experiments indicated that the FeS/carbon fibers are a promising remediation material for practical application.
基金supported by the National Natural Science Foundation of China(83418083)the Natural Science Foundation of Fujian Province(2019J01230).
文摘Modification is one of the most important and effective methods to improve the photoelectrocatalytic(PEC)performance of ZnO.In this paper,the Ru_(x)Zn_(1-x)O/Ti electrodes were prepared by thermal decomposition method and the effect of Ru content on those electrodes' electronic structure was analyzed through the first-principles calculation.Various tests were also performed to observe the microstructures and PEC performance.The results showed that as the Ru^(4+) transferred into ZnO lattice and replaced a number of Zn^(2+),the conduction band of ZnO moved downward and the valence band went upward.The number of photogenerated electron-hole pairs increased as the impurity levels appeared in the band gap.In addition,ZnO nanorods exhibited a smaller grain size and a rougher surface under the effect of Ru.Meanwhile,the RuO_(2) nanoparticles on the surface of ZnO nanorods acted as the electron-transfer channel,helping electrons transfer to the counter electrode and delaying the recombination of the electron-hole pairs.Specifically,the Ru_(x)Zn_(1-x)O/Ti electrodes with 9.375 mol% Ru exhibited the best PEC performance with a rhodamine B(RhB)removal rate of 97%,much higher than the combination of electrocatalysis(EC,12%)and photocatalysis(PC,50%),confirming the synergy of photoelectrocatalysis.
基金supported by the National Key R&D Program of China(Project Number 2018YFA0209500)the National Natural Science Foundation of China(21975209,21673197,21808191,and 21621091)+4 种基金the Fundamental Research Funds for the Central Universities of China(20720190037)the Natural Science Foundation of Fujian Province of China(2018J06003)the 111 Project(B16029)Special Project of Strategic Emerging Industries from Fujian Development and Reform CommissionCAS Key Laboratory of Bio-inspired Materials and Interfacial Science,Technical Institute of Physics and Chemistry,Chinese Academy of Sciences。
文摘Safe and precise control of gas flow is one of the key factors to many physical and chemical processes,such as degassing,natural gas transportation,and gas sensor.In practical application,it is essential for the gas-involved physicochemical process to keep everything under control and safe,which significantly relies on the controllability,safety,and stability of their valves.Here we show a light-responsive and corrosion-resistant gas valve with non-thermal effective liquid-gating positional flow control under a constant pressure by incorporating dynamic gating liquid with light responsiveness of solid porous substrate.Our experimental and theoretical analysis reveal that the photoisomerization of azobenzene-based molecular photoswitches on the porous substrate enabled the gas valve to possess a light-responsive and reversible variation of substantial critical pressure of non-thermal effective gas flow switch.Moreover,the chemically inert gating liquid prevented the solid substrate from corrosion and,by combining with the high spatiotemporal resolution of light,the gas valve realizes a precisely positional open and close under a steady-state pressure.The application demonstrations in our results show the potentials of the new gas valve for bringing opportunities to many applications,such as gas-involved reaction control in microfluidics,soft actuators,and beyond.
基金We gratefully acknowledge the support from the National Natural Science Foundation of China(grant No.21808191,21673197,21975209,and 21621091)the National Key R&D Program of China(grant No.2018YFA0209500)+2 种基金the Fundamental Research Funds for the Central Universities(grant No.20720190037)the Natural Science Foundation of Fujian Province of China(grant No.2018J06003)the Special Project of Strategic Emerging Industries from Fujian Development and Reform Commission.We thank Prof.C.Chen and Dr.Q.Kong for the preparation of GO at the Institute of Coal Chemistry,Chinese Academy of Sciences.
文摘The ability of membrane technologies to dynamically tune the transport behavior for gases and liquids is critical for their applications.Although various methods have been developed to improve membrane success,tradeoffs still exist among their properties,such as permeability,selectivity,fouling resistance,and stability,which can greatly affect the performance of membranes.Existing elastomeric membrane designs can provide antifracture properties and flexibility;however,these designs still face certain challenges,such as low tensile strength and reliability.Additionally,researchers have not yet thoroughly developed membranes that can avoid fouling issues while realizing precise dynamic control over the transport substances.In this study,we show a versatile strategy for preparing graphene oxide-reinforced elastomeric liquid gating membranes that can finely modulate and dynamically tune the sorting of a wide range of gases and liquids under constant applied pressures.Moreover,the produced membranes exhibit antifouling properties and are adaptable to different length scales,pressures,and environments.The filling of graphene oxide in the thermoplastic polyurethane matrix enhances the composites through hydrogen bonds.Experiments and theoretical calculations are carried out to demonstrate the stability of our system.Our membrane exhibits good stretchability,recovery,and durability due to the elastic nature of the solid matrix and dynamic nature of the gating liquid.Dynamic control over the transport of gases and liquids is achieved through our optimized interfacial design and controllable pore deformation,which is induced by mechanical stimuli.Our strategy will create new opportunities for many applications,such as gas-involved chemical reactions,multiphase separation,microfluidics,multiphase microreactors,and particulate material synthesis.