With the change of the main influencing factors such as structural configuration and impact conditions,reinforced concrete slabs exhibit different mechanical behaviors with different failure patterns,and the failure m...With the change of the main influencing factors such as structural configuration and impact conditions,reinforced concrete slabs exhibit different mechanical behaviors with different failure patterns,and the failure modes are transformed.In order to reveal the failure mode and transformation rule of reinforced concrete slabs under impact loads,a dynamic impact response test was carried out using a drop hammer test device.The dynamic data pertaining to the impact force,support reaction force,structural displacement,and reinforcement strain were obtained through the use of digital image correlation technology(DIC),impact force measurement,and strain measurement.The analysis of the ultimate damage state of the reinforced concrete slab identified four distinct types of impact failure modes:local failure by stamping,overall failure by stamping,local-overall coupling failure,and local failure by punching.Additionally,the influence laws of hammerhead shape,hammer height,and reinforcement ratio on the dynamic response and failure mode transformation of the slab were revealed.The results indicate that:(1)The local damage to the slab by the plane hammer is readily apparent,while the overall damage by the spherical hammer is more pronounced.(2)In comparison to the high reinforcement ratio slabs,the overall bending resistance of the low reinforcement ratio slabs is significantly inferior,and the slab back exhibits further cracks.(3)As the hammer height increases,the slab failure mode undergoes a transformation,shifting from local failure by stamping and overall failure by stamping to local-overall coupling failure and local failure by punching.(4)Three failure mode thresholds have been established,and by comparing the peak impact force with the failure thresholds,the failure mode of the slab can be effectively determined.展开更多
Fluoropolymers promise all-solid-state lithium metal batteries(ASLMBs)but suffer from two critical challenges.The first is the trade-off between ionic conductivity(σ)and lithium anode reactions,closely related to hig...Fluoropolymers promise all-solid-state lithium metal batteries(ASLMBs)but suffer from two critical challenges.The first is the trade-off between ionic conductivity(σ)and lithium anode reactions,closely related to high-content residual solvents.The second,usually consciously overlooked,is the fluoropolymer's inherent instability against alkaline lithium anodes.Here,we propose indium-based metal-organic frameworks(In-MOFs)as a multifunctional promoter to simultaneously address these two challenges,using poly(vinylidene fluoride-hexafluoropropylene)(PVH)as the typical fluoropolymer.In-MOF plays a trio:(1)adsorbing and converting free residual solvents into bonded states to prevent their side reactions with lithium anodes while retaining their advantages on Li~+transport;(2)forming inorganic-rich solid electrolyte interphase layers to prevent PVH from reacting with lithium anodes and promote uniform lithium deposition without dendrite growth;(3)reducing PVH crystallinity and promoting Li-salt dissociation.Therefore,the resulting PVH/In-MOF(PVH-IM)showcases excellent electrochemical stability against lithium anodes,delivering a 5550 h cycling at 0.2 m A cm^(-2)with a remarkable cumulative lithium deposition capacity of 1110 m Ah cm^(-2).It also exhibits an ultrahighσof 1.23×10^(-3)S cm^(-1)at 25℃.Moreover,all-solid-state LiFePO_4|PVH-IM|Li full cells show outstanding rate capability and cyclability(80.0%capacity retention after 280 cycles at 0.5C),demonstrating high potential for practical ASLMBs.展开更多
The ineluctable introduction of lithium salt to polymer solid-state electrolytes incurs a compromise between strength,ionic conductivity,and thickness.Here,we propose Al_(2)O_(3)-coated polyimide(AO/PI)porous film as ...The ineluctable introduction of lithium salt to polymer solid-state electrolytes incurs a compromise between strength,ionic conductivity,and thickness.Here,we propose Al_(2)O_(3)-coated polyimide(AO/PI)porous film as a high-strength substrate to support fast-ion-conducting polymer-in-salt(PIS)solid-state electrolytes,aiming to suppress lithium dendrite growth and improve full-cell performance.The Al_(2)O_(3)coating layer not only refines the wettability of polyimide porous film to PIS,but also performs as a high modulus protective layer to suppress the growth of lithium dendrites.The resulting PI/AO@PIS exhibits a small thickness of only 35μm with an outstanding tensile strength of 11.3 MPa and Young's modulus of 537.6 MPa.In addition,the PI/AO@PIS delivers a high ionic conductivity of 0.1 m S/cm at 25°C.As a result,the PI/AO@PIS enables symmetric Li cells to achieve exceptional cyclability for over 1000 h at 0.1 m A/cm2without noticeable lithium dendrite formation.Moreover,the PI/AO@PIS-based LiFePO4||Li full cells demonstrate outstanding rate performance(125.7 m Ah/g at 5 C)and impressive cycling stability(96.1%capacity retention at 1 C after 200 cycles).This work highlights the efficacy of enhancing the mechanical properties of polymer matrices and extending cell performance through the incorporation of a dense inorganic interface layer.展开更多
Composite solid electrolytes(CSEs)are promising for solid-state Li metal batteries but suffer from inferior room-temperature ionic conductivity due to sluggish ion transport and high cost due to expensive active ceram...Composite solid electrolytes(CSEs)are promising for solid-state Li metal batteries but suffer from inferior room-temperature ionic conductivity due to sluggish ion transport and high cost due to expensive active ceramic fillers.Here,a host–vip inversion engineering strategy is proposed to develop superionic CSEs using cost-effective SiO_(2) nanoparticles as passive ceramic hosts and poly(vinylidene fluoride-hexafluoropropylene)(PVH)microspheres as polymer vips,forming an unprecedented“polymer vip-in-ceramic host”(i.e.,PVH-in-SiO_(2))architecture differing from the traditional“ceramic vip-in-polymer host”.The PVH-in-SiO_(2) exhibits excellent Li-salt dissociation,achieving high-concentration free Li+.Owing to the low diffusion energy barriers and high diffusion coefficient,the free Li+is thermodynamically and kinetically favorable to migrate to and transport at the SiO_(2)/PVH interfaces.Consequently,the PVH-in-SiO_(2) delivers an exceptional ionic conductivity of 1.32.10−3 S cm−1 at 25℃(vs.typically 10−5–10−4 S cm−1 using high-cost active ceramics),achieved under an ultralow residual solvent content of 2.9 wt%(vs.8–15 wt%in other CSEs).Additionally,PVH-in-SiO_(2) is electrochemically stable with Li anode and various cathodes.Therefore,the PVH-in-SiO_(2) demonstrates excellent high-rate cyclability in LiFePO4|Li full cells(92.9%capacity-retention at 3C after 300 cycles under 25℃)and outstanding stability with high-mass-loading LiFePO4(9.2 mg cm−1)and high-voltage NCM622(147.1 mAh g−1).Furthermore,we verify the versatility of the host–vip inversion engineering strategy by fabricating Na-ion and K-ion-based PVH-in-SiO_(2) CSEs with similarly excellent promotions in ionic conductivity.Our strategy offers a simple,low-cost approach to fabricating superionic CSEs for large-scale application of solid-state Li metal batteries and beyond.展开更多
Interfacial solar evaporation holds immense potential for brine desalination with low carbon footprints and high energy utilization.Hydrogels,as a tunable material platform from the molecular level to the macroscopic ...Interfacial solar evaporation holds immense potential for brine desalination with low carbon footprints and high energy utilization.Hydrogels,as a tunable material platform from the molecular level to the macroscopic scale,have been considered the most promising candidate for solar evaporation.However,the simultaneous achievement of high evaporation efficiency and satisfactory tolerance to salt ions in brine remains a challenging scientific bottleneck,restricting the widespread application.Herein,we report ionization engineering,which endows polymer chains of hydrogels with electronegativity for impeding salt ions and activating water molecules,fundamentally overcoming the hydrogel salt-impeded challenge and dramatically expediting water evaporating in brine.The sodium dodecyl benzene sulfonate-modified carbon black is chosen as the solar absorbers.The hydrogel reaches a ground-breaking evaporation rate of 2.9 kg m−2 h−1 in 20 wt%brine with 95.6%efficiency under one sun irradiation,surpassing most of the reported literature.More notably,such a hydrogel-based evaporator enables extracting clean water from oversaturated salt solutions and maintains durability under different high-strength deformation or a 15-day continuous operation.Meantime,on the basis of the cation selectivity induced by the electronegativity,we first propose an all-day system that evaporates during the day and generates salinity-gradient electricity using waste-evaporated brine at night,anticipating pioneer a new opportunity for all-day resource-generating systems in fields of freshwater and electricity.展开更多
Photodynamic therapy(PDT) has been widely investigated for cancer therapy. The intracellular accumulation of reactive oxygen species(ROS)-damaged protein facilitates tumor cell apoptosis. However, there is growing evi...Photodynamic therapy(PDT) has been widely investigated for cancer therapy. The intracellular accumulation of reactive oxygen species(ROS)-damaged protein facilitates tumor cell apoptosis. However, there is growing evidence that the ubiquitin-proteasome pathway(UPP) significantly impedes PDT by preventing the enrichment of ROS-damaged proteins in tumor cells. To tackle this challenge, we report a facile dual-drug nanoassembly based on the discovery of an interesting co-assembly of bortezomib(BTZ, a proteasome inhibitor) and pyropheophorbide a(PPa) for proteasome inhibition-mediated PDT sensitization.The precisely engineered nanoassembly with the optimal dose ratio of BTZ and PPa demonstrates multiple advantages, including simple fabrication, high drug co-loading efficiency, flexible dose adjustment,good colloidal stability, long systemic circulation, favorable tumor-specific accumulation, as well as significant enrichment of ROS-damaged proteins in tumor cells. As a result, the cooperative nanoassembly exhibits potent synergistic antitumor activity in vivo. This study provides a novel dual-drug engineering modality for multimodal cancer treatment.展开更多
The sixth generation(6G)of mobile communication system is witnessing a new paradigm shift,i.e.,integrated sensing-communication system.A comprehensive dataset is a prerequisite for 6G integrated sensing-communication ...The sixth generation(6G)of mobile communication system is witnessing a new paradigm shift,i.e.,integrated sensing-communication system.A comprehensive dataset is a prerequisite for 6G integrated sensing-communication research.This paper develops a novel simulation dataset,named M3SC,for mixed multi-modal(MMM)sensing-communication integration,and the generation framework of the M3SC dataset is further given.To obtain multimodal sensory data in physical space and communication data in electromagnetic space,we utilize Air-Sim and WaveFarer to collect multi-modal sensory data and exploit Wireless InSite to collect communication data.Furthermore,the in-depth integration and precise alignment of AirSim,WaveFarer,andWireless InSite are achieved.The M3SC dataset covers various weather conditions,multiplex frequency bands,and different times of the day.Currently,the M3SC dataset contains 1500 snapshots,including 80 RGB images,160 depth maps,80 LiDAR point clouds,256 sets of mmWave waveforms with 8 radar point clouds,and 72 channel impulse response(CIR)matrices per snapshot,thus totaling 120,000 RGB images,240,000 depth maps,120,000 LiDAR point clouds,384,000 sets of mmWave waveforms with 12,000 radar point clouds,and 108,000 CIR matrices.The data processing result presents the multi-modal sensory information and communication channel statistical properties.Finally,the MMM sensing-communication application,which can be supported by the M3SC dataset,is discussed.展开更多
Although it is reported that the targeting ability of hyaluronic acid(HA)-based nanoparticles(NPs) is molecular weight(MW) dependent,the influence of HA MW on targeting efficiency of HA-functionalized NPs and the unde...Although it is reported that the targeting ability of hyaluronic acid(HA)-based nanoparticles(NPs) is molecular weight(MW) dependent,the influence of HA MW on targeting efficiency of HA-functionalized NPs and the underlying mechanism remain elusive. In this study,we constituted three HA-functionalized Dox-loaded NPs(Dox/HCVs) different HA MWs(7,63,and 102 k Da) and attempted to illustrate the effects of HA MW on the targeting efficiency.The three Dox/HCVs had similar physiochemical and pharmaceutical characteristics,but showed different affinity to CD44 receptor. Furthermore,Dox/HCV-63 exerted the best targeting effect and the highest cytotoxicity compared with Dox/HCV-7 and Dox/HCV-102. It was interesting to found that both the HA-CD44 binding affinity and induced CD44 clustering by HA-based NPs were HA MW-dependent,the two of which determine the apparent targeting efficacy of Dox/HCV NPs in the conflicting directions. Those results laid a good foundation for rationally designing HA-based NPs in cancer therapy.展开更多
Self-nanoemulsifying drug delivery system(SNEDDS) has emerged as a promising platform to improve oral absorption of drugs with poor solubility and low permeability. However,large polarity molecules with insufficient l...Self-nanoemulsifying drug delivery system(SNEDDS) has emerged as a promising platform to improve oral absorption of drugs with poor solubility and low permeability. However,large polarity molecules with insufficient lipid solubility,such as paclitaxel(PTX),would suffer from inferior formulation of SNEDDS due to poor compatibility. Herein,phospholipid-drug complex(PLDC) and SNEDDS were integrated into one system to facilitate oral delivery of PTX. First,PTX was formulated into PLDC in response to its inferior physicochemical properties. Then,the prepared PLDC was further formulated into SNEDDS by integrating these two drug delivery technologies into one system(PLDC-SNEDDS). After PLDC-SNEDDS dispersed in aqueous medium,nanoemulsion was formed immediately with an average particle size of ~30 nm. Furthermore,the nanomulsion of PLDC-SNEDDS showed good colloidal stability in both HCl solution(0.1 mol/l,p H 1.0) and phosphate buffer solution(PBS,p H 6.8). In vivo,PTX-PLDC-SNEDDS showed distinct advantages in terms of oral absorption efficiency,with a3.42-fold and 2.13-fold higher bioavailability than PTX-PLDC and PTX solution,respectively.Our results suggest that the integration of PLDC into SNEDDS could be utilized to facilitate the oral delivery of hydrophobic drugs with large polarity.展开更多
In order to better control the quality of Flos Puerariae(FP),qualitative and quantitative analyses were initially performed by using chemical fingerprint and chemometrics methods in this study.First,the fingerprint of...In order to better control the quality of Flos Puerariae(FP),qualitative and quantitative analyses were initially performed by using chemical fingerprint and chemometrics methods in this study.First,the fingerprint of FP was developed by HPLC and the chemical markers were screened out by similarity analysis(SA),hierarchical clustering analysis(HCA),principal components analysis(PCA),and orthogonal partial least squares discriminant analysis(OPLS-DA).Next,the chemical constituents in FP were profiled and identified by HPLC coupled to Fourier transform ion cyclotron resonance mass spectrometry(HPLCFT-ICR MS).Then,the characteristic constituents in FP were quantitatively analyzed by HPLC.As a result,31 common peaks were assigned in the fingerprint and 6 of them were considered as qualitative markers.A total of 35 chemical constituents were detected by HPLC-FT-ICR MS and 16 of them were unambiguously identified by comparing retention time,UV absorption wavelength,accurate mass,and MS/MS data with those of reference standards.Subsequently,the contents of glycitin,genistin,tectoridin,glycitein,genistein,and tectorigenin in 13 batches of FP were detected,ranging from 0.4438 to 11.06 mg/g,0.955 to 1.726 mg/g,9.81 to 57.22 mg/g,3.349 to 41.60 mg/g,0.3576 to 0.989 mg/g,and 2.126 to 9.99 mg/g,respectively.In conclusion,fingerprint analysis in combination with chemometrics methods could discover chemical markers for improving the quality control standard of FP.It is expected that the strategy applied in this study will be valuable for further quality control of other traditional Chinese medicines.展开更多
One of the major barriers in utilizing prodrug nanocarriers for cancer therapy is the slow release of parent drug in tumors.Tumor cells generally display the higher oxidative level than normal cells,and also displayed...One of the major barriers in utilizing prodrug nanocarriers for cancer therapy is the slow release of parent drug in tumors.Tumor cells generally display the higher oxidative level than normal cells,and also displayed the heterogeneity in terms of redox homeostasis level.We previously found that the disulfide bond-linkage demonstrates surprising oxidationsensitivity to form the hydrophilic sulfoxide and sulphone groups.Herein,we develop oxidation-strengthened prodrug nanosystem loaded with pyropheophorbide a(PPa)to achieve light-activatable cascade drug release and enhance therapeutic efficacy.The disulfide bond-driven prodrug nanosystems not only respond to the redox-heterogeneity in tumor,but also respond to the exogenous oxidant(singlet oxygen)elicited by photosensitizers.Once the prodrug nanoparticles(NPs)are activated under irradiation,they would undergo an oxidative self-strengthened process,resulting in a facilitated drug cascade release.The IC50 value of the PPa@PTX-S-S NPs without irradiation was 2-fold higher than those of NPs plus irradiation.In vivo,the PPa@PTX prodrug NPs display prolonged systemic circulation and increased accumulation in tumor site.The PPa@PTXS-S NPs showed much higher efficiency than free PTX or the PPa@PTX-C-C NPs to suppress the growth of 4 T1 tumors.Therefore,this novel oxidation-strengthened disulfide-bridged prodrug-nanosystem has a great potential in the enhanced efficacy of cancer synergetic photochemotherapy.展开更多
Adolescent binge drinking leads to long-lasting disorders of the adult central nervous system,particularly aberrant hippocampal neurogenesis.In this study,we applied in vivo fluorescent tracing using NestinCreERT2::Ro...Adolescent binge drinking leads to long-lasting disorders of the adult central nervous system,particularly aberrant hippocampal neurogenesis.In this study,we applied in vivo fluorescent tracing using NestinCreERT2::Rosa26-tdTomato mice and analyzed the endogenous neurogenesis lineage progression of neural stem cells(NSCs)and dendritic spine formation of newborn neurons in the subgranular zone of the dentate gyrus.We found abnormal orientation of tamoxifen-induced tdTomato+(tdTom^(+))NSCs in adult mice 2 months after treatment with EtOH(5.0 g/kg,i.p.)for 7 consecutive days.EtOH markedly inhibited tdTom^(+)NSCs activation and hippocampal neurogenesis in mouse dentate gyrus from adolescence to adulthood.EtOH(100 mM)also significantly inhibited the proliferation to 39.2%and differentiation of primary NSCs in vitro.Adult mice exposed to EtOH also exhibited marked inhibitions in dendritic spine growth and newborn neuron maturation in the dentate gyrus,which was partially reversed by voluntary running or inhibition of the mammalian target of rapamycinenhancer of zeste homolog 2 pathway.In vivo tracing revealed that EtOH induced abnormal orientation of tdTom+NSCs and spatial misposition defects of newborn neurons,thus causing the disturbance of hippocampal neurogenesis and dendritic spine remodeling in mice.展开更多
In the present paper, chiral mesoporous silica nano-cocoon(A-CMSN) functionalized with amino group was synthesized, and its loading and release of indomethacin(IMC), a poorly soluble drug, was studied. Due to the use ...In the present paper, chiral mesoporous silica nano-cocoon(A-CMSN) functionalized with amino group was synthesized, and its loading and release of indomethacin(IMC), a poorly soluble drug, was studied. Due to the use of chiral anionic surfactants as a template, ACMSN possessed 2D hexagonal nano-cocoon morphology with curled channels on its surface, which was quite different from another 2D hexagonal mesoporous silica nanoparticles(MCM-41) with straightway channels. After being loaded into the two silica carriers by hydrogen bond, crystalline IMC converted to amorphous form, leading to the improved drug dissolution. And IMC loading capacity of A-CMSN was higher than MCM-41 because curled loading process originating from curvature chiral channels can hold more drug molecules. Compared with IMC, IMC loaded A-CMSN presented obviously fast release throughout the in vitro release experiment, while IMC loaded MCM-41 released faster than IMC at the initial 5 h then showed controlled slow release afterwards, which was closely related to the mesoporous silica nanoparticles and different channel mesostructures of these two carriers. A-CMSN possessed nano-cocoon morphology with curled 2D hexagonal channel and its channel length was shorter than MCM-41, therefore IMC molecules can easily get rid of the constraint of A-CMSN then to be surrounded by dissolution medium.展开更多
The use of fiber as a catalyst carrier to construct heterogeneous catalysts with good catalytic activity and recycling performance has received wide attention.In this study,three phenylboronic acid functionalized poly...The use of fiber as a catalyst carrier to construct heterogeneous catalysts with good catalytic activity and recycling performance has received wide attention.In this study,three phenylboronic acid functionalized polyacrylonitrile fiber(PANF)catalysts were synthesized by amination and quaternization.Fourier transform infrared spectroscopy,X-ray diffractometry,scanning electron microscopy,and X-ray photoelectron spectroscopy were used to verify the successful grafting of phenylboronic acid and the structural integrity of the fiber catalyst after recycling.The activity of the catalysts was explored with the Friedel–Crafts alkylation between indole and aromatic aldehydes.The results indicate that the synthesized catalyst(PANp-BAF)in which the phenylboronic acid functional group was linked at the para position,exhibited the highest catalytic activity for the Friedel–Crafts alkylation.The substrate scope experiments confirmed that the catalyst has outstanding catalytic activity for most aromatic aldehydes,especially for those containing moderate electron donating groups.Moreover,the catalyst can be reused eight times in water without significant decrease in its catalytic activity.Further,the scale-up experiment confirmed that the fiber catalyst has a certain potential for industrial application.展开更多
In gas insulation switch(GIS)substation,secondary devices such as linemonitoring devices are placed in the switching field,and these electronic devices are vulnerable to transient electromagnetic interference caused b...In gas insulation switch(GIS)substation,secondary devices such as linemonitoring devices are placed in the switching field,and these electronic devices are vulnerable to transient electromagnetic interference caused by switching operation.In order to facilitate the measurement and research of electromagnetic disturbance data under different working conditions,a simulation test device is developed in this paper,which can be used to simulate electromagnetic disturbance of GIS substation sensor and secondary device port under switch operation.A four-channel parallel gas switch was designed,and the main characteristic parameters of electromagnetic disturbance generated by the simulation device were measured by using high-frequency pulse power supply as the excitation source.The comparison between the measured waveform and the measured disturbance characteristic parameters of GIS substation shows that it is in good agreement with the measured waveform characteristics,conforms to the basic characteristics of damped oscillation wave,and can be used in the secondary equipment port disturbance voltage coupling characteristics,protection measures evaluation and assessment method research.展开更多
In the existing power system with a large-scale hydrogen storage system,there are problems such as low efficiency of electric-hydrogen-electricity conversion and single modeling of the hydrogen storage system.In order...In the existing power system with a large-scale hydrogen storage system,there are problems such as low efficiency of electric-hydrogen-electricity conversion and single modeling of the hydrogen storage system.In order to improve the hydrogen utilization rate of hydrogen storage system in the process of participating in the power grid operation,and speed up the process of electric-hydrogen-electricity conversion.This article provides a detailed introduction to the mathematical and electrical models of various components of the hydrogen storage unit,and also establishes a charging and discharging efficiency model that considers the temperature and internal gas partial pressure of the hydrogen storage unit.These models are of great significance for studying and optimizing gas storage technology.Through these models,the performance of gas storage units can be better understood and improved.These studies are very helpful for improving energy storage efficiency and sustainable development.The factors affecting the charge-discharge efficiency of hydrogen storage units are analyzed.By integrating the models of each unit and considering the capacity degradation of the hydrogen storage system,we can construct an efficiency model for a large hydrogen storage system and power conversion system.In addition,the simulation models of the hydrogen production system and hydrogen consumption system were established in MATLAB/Simulink.The accuracy and effectiveness of the simulation model were proved by comparing the output voltage variation curve of the simulation with the polarization curve of the typical hydrogen production system and hydrogen consumption system.The results show that the charge-discharge efficiency of the hydrogen storage unit increases with the increase of operating temperature,and H2 and O2 partial voltage have little influence on the charge-discharge efficiency.In the process of power conversion system converter rectification operation,its efficiency decreases with the increase of temperature,while in the process of inverter operation,power conversion system efficiency increases with the increase of temperature.Combined with the efficiency of each hydrogen storage unit and power conversion system converter,the upper limit of the capacity loss of different hydrogen storage units was set.The optimal charge-discharge efficiency of the hydrogen storage system was obtained by using the Cplex solver at 36.46%and 66.34%.展开更多
Interference cancellation scheme without feedback is proposed for X channels with four antennas at each user. Space-time codeword with Alamouti structure is designed for each user. Codewords are combined according a c...Interference cancellation scheme without feedback is proposed for X channels with four antennas at each user. Space-time codeword with Alamouti structure is designed for each user. Codewords are combined according a certain rule. The unwanted codewords are cancelled by linear operation on the received signals. Then, multi-user interference is mitigated by the orthogonal property of the Alamouti code. Comparing with the existing scheme for the same scene, feedback information is not required in the proposed scheme. So the transmission efficiency is improved.展开更多
Winter poses a high risk for spreading infectious respiratory diseases,particularly in classrooms,which are known hotspots for cross-infection.The health hazards in classrooms lacking mechanical ventilation systems of...Winter poses a high risk for spreading infectious respiratory diseases,particularly in classrooms,which are known hotspots for cross-infection.The health hazards in classrooms lacking mechanical ventilation systems often go unnoticed.To address this issue,we studied the risk of respiratory infection transmission in such environments during winter by assessing the spread of contaminants using computational fluid dynamics(CFD).We evaluated four common airflow setups(split-type air conditioner,open door,open window,and both door and window open)in classrooms without mechanical ventilation.Our findings indicate that while split air conditioners provide optimal thermal comfort,they significantly increase exposure risk.Conversely,simply opening a door can effectively balance thermal comfort with a reduced exposure risk—particularly when the infected individual is near the door,leading to a minimal 0.01%average intake fraction.Furthermore,under varying ventilation scenarios,the sensitivity of exposure risk to location changes of infected individuals differs significantly.Specifically,when a split-type air conditioner is used,occupant exposure is largely unaffected by changes in the location of the infected individual.However,the exposure risk becomes highly sensitive to location changes of infected individuals when a door or window is used for ventilation.Strategic positioning of the infected individual can decrease indoor exposure risk by up to 94%with the door open and 67%with the window open.Additionally,when the door and window are both open,the dependency of occupant exposure on the location of the infected individual decreases.In this case,the exposure risk for indoor occupants is low,regardless of the position of the infected individual.展开更多
Climate change in the Arctic serves as a pivotal indicator of alterations in the global climate system,with clouds playing an essential role in regulating the surface radiative energy balance in the Arctic.Elucidating...Climate change in the Arctic serves as a pivotal indicator of alterations in the global climate system,with clouds playing an essential role in regulating the surface radiative energy balance in the Arctic.Elucidating the patterns of Arctic cloud variability and the underlying mechanisms is of paramount scientific importance for understanding Arctic climate change.Spatiotemporal analysis of Arctic cloud characteristics reveals that since the onset of the 21st century,low clouds have predominantly comprised the Arctic summer cloud fraction(approximately 60%),followed by middle clouds(approximately 30%).The total-cloud fraction has exhibited a marked increasing trend,especially in the Beaufort Sea and Chukchi Sea(0.45%/yr).An attribution analysis suggests that the changes in the Arctic cloud fraction are chiefly driven by trends in two atmospheric circulation modes:The Arctic Oscillation(AO)and the Arctic dipole anomaly(DA).During positive phases of the AO,the cloud fraction increases across all Arctic basins.Conversely,in the positive phases of the DA,the cloud fraction decreases in the Beaufort Sea,Chukchi Sea,and Greenland Sea,whereas it increases in the East Siberian Sea,Kara Sea,and Barents Sea,indicating an“east-west”dipole distribution.Since 2000,the AO has been on an upward trend,whereas the DA has been declining.The combined effect of these two modes has resulted in a significant increase in the cloud fraction within the Beaufort Sea region.Further examination of cloud radiative effects indicates that an increase in the cloud fraction intensifies both longwave warming and shortwave cooling effects,leading to an overall net negative radiative effect.Analyzing the long-term trends in Arctic summer clouds enhances our comprehension of Arctic climate change.展开更多
The tumor microenvironment-sensitive prodrug-based nanoparticles(NPs)have emerged as a promising drug delivery system(DDS).The shape of these particles plays a crucial role in their in vivo behavior.However,non-spheri...The tumor microenvironment-sensitive prodrug-based nanoparticles(NPs)have emerged as a promising drug delivery system(DDS).The shape of these particles plays a crucial role in their in vivo behavior.However,non-spherical organic NPs are rarely reported due to the inherent flexibility and variability of organic molecules.Herein,we fabricate reduction-sensitive prodrug NPs and explore the impact of their morphology properties on their in vivo fate.Prodrugs are self-assembled into spherical NPs with distearoyl phosphoethanolamine-PEG2000(DSPE-PEG2k),or into rod-shaped NPs with D-a-tocopherol polyethylene glycol 2000 succinate(TPGS2k)due to the stronger binding energy.In comparison with spherical NPs,the endocytosis of rod-shaped NPs predominantly relies on caveolae-mediated pathways rather than clathrin-mediated ones,potentially avoiding degradation by lysosomes.Additionally,the rod-shaped NPs exhibit prolonged circulation time,increased tumor accumulation,and enhanced antitumor ability.Our current findings reveal the significant effect of particle shape on the behavior of prodrug NPs and introduce a novel paradigm for high-efficacy cancer therapy of prodrug NPs.展开更多
基金Supported by the National Natural Science Foundation of China(Grant No.52078283)Shandong Provincial Natural Science Foundation(Project No.ZR2024MA094)。
文摘With the change of the main influencing factors such as structural configuration and impact conditions,reinforced concrete slabs exhibit different mechanical behaviors with different failure patterns,and the failure modes are transformed.In order to reveal the failure mode and transformation rule of reinforced concrete slabs under impact loads,a dynamic impact response test was carried out using a drop hammer test device.The dynamic data pertaining to the impact force,support reaction force,structural displacement,and reinforcement strain were obtained through the use of digital image correlation technology(DIC),impact force measurement,and strain measurement.The analysis of the ultimate damage state of the reinforced concrete slab identified four distinct types of impact failure modes:local failure by stamping,overall failure by stamping,local-overall coupling failure,and local failure by punching.Additionally,the influence laws of hammerhead shape,hammer height,and reinforcement ratio on the dynamic response and failure mode transformation of the slab were revealed.The results indicate that:(1)The local damage to the slab by the plane hammer is readily apparent,while the overall damage by the spherical hammer is more pronounced.(2)In comparison to the high reinforcement ratio slabs,the overall bending resistance of the low reinforcement ratio slabs is significantly inferior,and the slab back exhibits further cracks.(3)As the hammer height increases,the slab failure mode undergoes a transformation,shifting from local failure by stamping and overall failure by stamping to local-overall coupling failure and local failure by punching.(4)Three failure mode thresholds have been established,and by comparing the peak impact force with the failure thresholds,the failure mode of the slab can be effectively determined.
基金the financial support from the 261 Project of MIITNatural Science Foundation of Jiangsu Province(No.BK20240179)。
文摘Fluoropolymers promise all-solid-state lithium metal batteries(ASLMBs)but suffer from two critical challenges.The first is the trade-off between ionic conductivity(σ)and lithium anode reactions,closely related to high-content residual solvents.The second,usually consciously overlooked,is the fluoropolymer's inherent instability against alkaline lithium anodes.Here,we propose indium-based metal-organic frameworks(In-MOFs)as a multifunctional promoter to simultaneously address these two challenges,using poly(vinylidene fluoride-hexafluoropropylene)(PVH)as the typical fluoropolymer.In-MOF plays a trio:(1)adsorbing and converting free residual solvents into bonded states to prevent their side reactions with lithium anodes while retaining their advantages on Li~+transport;(2)forming inorganic-rich solid electrolyte interphase layers to prevent PVH from reacting with lithium anodes and promote uniform lithium deposition without dendrite growth;(3)reducing PVH crystallinity and promoting Li-salt dissociation.Therefore,the resulting PVH/In-MOF(PVH-IM)showcases excellent electrochemical stability against lithium anodes,delivering a 5550 h cycling at 0.2 m A cm^(-2)with a remarkable cumulative lithium deposition capacity of 1110 m Ah cm^(-2).It also exhibits an ultrahighσof 1.23×10^(-3)S cm^(-1)at 25℃.Moreover,all-solid-state LiFePO_4|PVH-IM|Li full cells show outstanding rate capability and cyclability(80.0%capacity retention after 280 cycles at 0.5C),demonstrating high potential for practical ASLMBs.
基金the financial support from the 261Project of MIIT and Natural Science Foundation of Jiangsu Province(No.BK20240179)。
文摘The ineluctable introduction of lithium salt to polymer solid-state electrolytes incurs a compromise between strength,ionic conductivity,and thickness.Here,we propose Al_(2)O_(3)-coated polyimide(AO/PI)porous film as a high-strength substrate to support fast-ion-conducting polymer-in-salt(PIS)solid-state electrolytes,aiming to suppress lithium dendrite growth and improve full-cell performance.The Al_(2)O_(3)coating layer not only refines the wettability of polyimide porous film to PIS,but also performs as a high modulus protective layer to suppress the growth of lithium dendrites.The resulting PI/AO@PIS exhibits a small thickness of only 35μm with an outstanding tensile strength of 11.3 MPa and Young's modulus of 537.6 MPa.In addition,the PI/AO@PIS delivers a high ionic conductivity of 0.1 m S/cm at 25°C.As a result,the PI/AO@PIS enables symmetric Li cells to achieve exceptional cyclability for over 1000 h at 0.1 m A/cm2without noticeable lithium dendrite formation.Moreover,the PI/AO@PIS-based LiFePO4||Li full cells demonstrate outstanding rate performance(125.7 m Ah/g at 5 C)and impressive cycling stability(96.1%capacity retention at 1 C after 200 cycles).This work highlights the efficacy of enhancing the mechanical properties of polymer matrices and extending cell performance through the incorporation of a dense inorganic interface layer.
基金financial support from the National Natural Science Foundation of China(Nos.52250010 and 52201242)the 261 Project of MIIT,Natural Science Foundation of Jiangsu Province(No.BK20240179)the Young Elite Scientists Sponsorship Program by CAST(No.2021QNRC001).
文摘Composite solid electrolytes(CSEs)are promising for solid-state Li metal batteries but suffer from inferior room-temperature ionic conductivity due to sluggish ion transport and high cost due to expensive active ceramic fillers.Here,a host–vip inversion engineering strategy is proposed to develop superionic CSEs using cost-effective SiO_(2) nanoparticles as passive ceramic hosts and poly(vinylidene fluoride-hexafluoropropylene)(PVH)microspheres as polymer vips,forming an unprecedented“polymer vip-in-ceramic host”(i.e.,PVH-in-SiO_(2))architecture differing from the traditional“ceramic vip-in-polymer host”.The PVH-in-SiO_(2) exhibits excellent Li-salt dissociation,achieving high-concentration free Li+.Owing to the low diffusion energy barriers and high diffusion coefficient,the free Li+is thermodynamically and kinetically favorable to migrate to and transport at the SiO_(2)/PVH interfaces.Consequently,the PVH-in-SiO_(2) delivers an exceptional ionic conductivity of 1.32.10−3 S cm−1 at 25℃(vs.typically 10−5–10−4 S cm−1 using high-cost active ceramics),achieved under an ultralow residual solvent content of 2.9 wt%(vs.8–15 wt%in other CSEs).Additionally,PVH-in-SiO_(2) is electrochemically stable with Li anode and various cathodes.Therefore,the PVH-in-SiO_(2) demonstrates excellent high-rate cyclability in LiFePO4|Li full cells(92.9%capacity-retention at 3C after 300 cycles under 25℃)and outstanding stability with high-mass-loading LiFePO4(9.2 mg cm−1)and high-voltage NCM622(147.1 mAh g−1).Furthermore,we verify the versatility of the host–vip inversion engineering strategy by fabricating Na-ion and K-ion-based PVH-in-SiO_(2) CSEs with similarly excellent promotions in ionic conductivity.Our strategy offers a simple,low-cost approach to fabricating superionic CSEs for large-scale application of solid-state Li metal batteries and beyond.
基金the National Natural Science Foundation of China(Grant No.52076028).
文摘Interfacial solar evaporation holds immense potential for brine desalination with low carbon footprints and high energy utilization.Hydrogels,as a tunable material platform from the molecular level to the macroscopic scale,have been considered the most promising candidate for solar evaporation.However,the simultaneous achievement of high evaporation efficiency and satisfactory tolerance to salt ions in brine remains a challenging scientific bottleneck,restricting the widespread application.Herein,we report ionization engineering,which endows polymer chains of hydrogels with electronegativity for impeding salt ions and activating water molecules,fundamentally overcoming the hydrogel salt-impeded challenge and dramatically expediting water evaporating in brine.The sodium dodecyl benzene sulfonate-modified carbon black is chosen as the solar absorbers.The hydrogel reaches a ground-breaking evaporation rate of 2.9 kg m−2 h−1 in 20 wt%brine with 95.6%efficiency under one sun irradiation,surpassing most of the reported literature.More notably,such a hydrogel-based evaporator enables extracting clean water from oversaturated salt solutions and maintains durability under different high-strength deformation or a 15-day continuous operation.Meantime,on the basis of the cation selectivity induced by the electronegativity,we first propose an all-day system that evaporates during the day and generates salinity-gradient electricity using waste-evaporated brine at night,anticipating pioneer a new opportunity for all-day resource-generating systems in fields of freshwater and electricity.
基金financially supported by the Liaoning Revitalization Talents Program (No. XLYC1907129)the Excellent Youth Science Foundation of Liaoning Province (No. 2020-YQ-06)the China Postdoctoral Science Foundation (No. 2020M670794)。
文摘Photodynamic therapy(PDT) has been widely investigated for cancer therapy. The intracellular accumulation of reactive oxygen species(ROS)-damaged protein facilitates tumor cell apoptosis. However, there is growing evidence that the ubiquitin-proteasome pathway(UPP) significantly impedes PDT by preventing the enrichment of ROS-damaged proteins in tumor cells. To tackle this challenge, we report a facile dual-drug nanoassembly based on the discovery of an interesting co-assembly of bortezomib(BTZ, a proteasome inhibitor) and pyropheophorbide a(PPa) for proteasome inhibition-mediated PDT sensitization.The precisely engineered nanoassembly with the optimal dose ratio of BTZ and PPa demonstrates multiple advantages, including simple fabrication, high drug co-loading efficiency, flexible dose adjustment,good colloidal stability, long systemic circulation, favorable tumor-specific accumulation, as well as significant enrichment of ROS-damaged proteins in tumor cells. As a result, the cooperative nanoassembly exhibits potent synergistic antitumor activity in vivo. This study provides a novel dual-drug engineering modality for multimodal cancer treatment.
基金This work was supported in part by the Ministry National Key Research and Development Project(Grant No.2020AAA0108101)the National Natural Science Foundation of China(Grants No.62125101,62341101,62001018,and 62301011)+1 种基金Shandong Natural Science Foundation(Grant No.ZR2023YQ058)the New Cornerstone Science Foundation through the XPLORER PRIZE.The authors would like to thank Mengyuan Lu and Zengrui Han for their help in the construction of electromagnetic space in Wireless InSite simulation platform and Weibo Wen,Qi Duan,and Yong Yu for their help in the construction of phys ical space in AirSim simulation platform.
文摘The sixth generation(6G)of mobile communication system is witnessing a new paradigm shift,i.e.,integrated sensing-communication system.A comprehensive dataset is a prerequisite for 6G integrated sensing-communication research.This paper develops a novel simulation dataset,named M3SC,for mixed multi-modal(MMM)sensing-communication integration,and the generation framework of the M3SC dataset is further given.To obtain multimodal sensory data in physical space and communication data in electromagnetic space,we utilize Air-Sim and WaveFarer to collect multi-modal sensory data and exploit Wireless InSite to collect communication data.Furthermore,the in-depth integration and precise alignment of AirSim,WaveFarer,andWireless InSite are achieved.The M3SC dataset covers various weather conditions,multiplex frequency bands,and different times of the day.Currently,the M3SC dataset contains 1500 snapshots,including 80 RGB images,160 depth maps,80 LiDAR point clouds,256 sets of mmWave waveforms with 8 radar point clouds,and 72 channel impulse response(CIR)matrices per snapshot,thus totaling 120,000 RGB images,240,000 depth maps,120,000 LiDAR point clouds,384,000 sets of mmWave waveforms with 12,000 radar point clouds,and 108,000 CIR matrices.The data processing result presents the multi-modal sensory information and communication channel statistical properties.Finally,the MMM sensing-communication application,which can be supported by the M3SC dataset,is discussed.
基金supported by the National Basic Research Program of China (No. 81573371)the key projects of Liaoning Province Department of Education (No. 2017LZD03)
文摘Although it is reported that the targeting ability of hyaluronic acid(HA)-based nanoparticles(NPs) is molecular weight(MW) dependent,the influence of HA MW on targeting efficiency of HA-functionalized NPs and the underlying mechanism remain elusive. In this study,we constituted three HA-functionalized Dox-loaded NPs(Dox/HCVs) different HA MWs(7,63,and 102 k Da) and attempted to illustrate the effects of HA MW on the targeting efficiency.The three Dox/HCVs had similar physiochemical and pharmaceutical characteristics,but showed different affinity to CD44 receptor. Furthermore,Dox/HCV-63 exerted the best targeting effect and the highest cytotoxicity compared with Dox/HCV-7 and Dox/HCV-102. It was interesting to found that both the HA-CD44 binding affinity and induced CD44 clustering by HA-based NPs were HA MW-dependent,the two of which determine the apparent targeting efficacy of Dox/HCV NPs in the conflicting directions. Those results laid a good foundation for rationally designing HA-based NPs in cancer therapy.
基金financially supported by the National Nature Science Foundation of China (No. 81703451)the China Postdoctoral Science Foundation (No. 2017M611269 and 2018T110233)
文摘Self-nanoemulsifying drug delivery system(SNEDDS) has emerged as a promising platform to improve oral absorption of drugs with poor solubility and low permeability. However,large polarity molecules with insufficient lipid solubility,such as paclitaxel(PTX),would suffer from inferior formulation of SNEDDS due to poor compatibility. Herein,phospholipid-drug complex(PLDC) and SNEDDS were integrated into one system to facilitate oral delivery of PTX. First,PTX was formulated into PLDC in response to its inferior physicochemical properties. Then,the prepared PLDC was further formulated into SNEDDS by integrating these two drug delivery technologies into one system(PLDC-SNEDDS). After PLDC-SNEDDS dispersed in aqueous medium,nanoemulsion was formed immediately with an average particle size of ~30 nm. Furthermore,the nanomulsion of PLDC-SNEDDS showed good colloidal stability in both HCl solution(0.1 mol/l,p H 1.0) and phosphate buffer solution(PBS,p H 6.8). In vivo,PTX-PLDC-SNEDDS showed distinct advantages in terms of oral absorption efficiency,with a3.42-fold and 2.13-fold higher bioavailability than PTX-PLDC and PTX solution,respectively.Our results suggest that the integration of PLDC into SNEDDS could be utilized to facilitate the oral delivery of hydrophobic drugs with large polarity.
基金supported by Liaoning Province Natural Science Foundation(Grant No.:2021-MS-220).
文摘In order to better control the quality of Flos Puerariae(FP),qualitative and quantitative analyses were initially performed by using chemical fingerprint and chemometrics methods in this study.First,the fingerprint of FP was developed by HPLC and the chemical markers were screened out by similarity analysis(SA),hierarchical clustering analysis(HCA),principal components analysis(PCA),and orthogonal partial least squares discriminant analysis(OPLS-DA).Next,the chemical constituents in FP were profiled and identified by HPLC coupled to Fourier transform ion cyclotron resonance mass spectrometry(HPLCFT-ICR MS).Then,the characteristic constituents in FP were quantitatively analyzed by HPLC.As a result,31 common peaks were assigned in the fingerprint and 6 of them were considered as qualitative markers.A total of 35 chemical constituents were detected by HPLC-FT-ICR MS and 16 of them were unambiguously identified by comparing retention time,UV absorption wavelength,accurate mass,and MS/MS data with those of reference standards.Subsequently,the contents of glycitin,genistin,tectoridin,glycitein,genistein,and tectorigenin in 13 batches of FP were detected,ranging from 0.4438 to 11.06 mg/g,0.955 to 1.726 mg/g,9.81 to 57.22 mg/g,3.349 to 41.60 mg/g,0.3576 to 0.989 mg/g,and 2.126 to 9.99 mg/g,respectively.In conclusion,fingerprint analysis in combination with chemometrics methods could discover chemical markers for improving the quality control standard of FP.It is expected that the strategy applied in this study will be valuable for further quality control of other traditional Chinese medicines.
基金financially supported by National Nature Science Foundation of China(No.81872816,81703451)Liaoning Revitalization Talents Program,No XLYC1808017+2 种基金Key projects of Technology bureau in Shenyang,No18400408Key projects of Liaoning Province Department of Education,No.2017LZD03supported by Heilongjiang Provincial Key Laboratory of Plant Genetic Engineering and Biological Fermentation Engineering for Cold Region。
文摘One of the major barriers in utilizing prodrug nanocarriers for cancer therapy is the slow release of parent drug in tumors.Tumor cells generally display the higher oxidative level than normal cells,and also displayed the heterogeneity in terms of redox homeostasis level.We previously found that the disulfide bond-linkage demonstrates surprising oxidationsensitivity to form the hydrophilic sulfoxide and sulphone groups.Herein,we develop oxidation-strengthened prodrug nanosystem loaded with pyropheophorbide a(PPa)to achieve light-activatable cascade drug release and enhance therapeutic efficacy.The disulfide bond-driven prodrug nanosystems not only respond to the redox-heterogeneity in tumor,but also respond to the exogenous oxidant(singlet oxygen)elicited by photosensitizers.Once the prodrug nanoparticles(NPs)are activated under irradiation,they would undergo an oxidative self-strengthened process,resulting in a facilitated drug cascade release.The IC50 value of the PPa@PTX-S-S NPs without irradiation was 2-fold higher than those of NPs plus irradiation.In vivo,the PPa@PTX prodrug NPs display prolonged systemic circulation and increased accumulation in tumor site.The PPa@PTXS-S NPs showed much higher efficiency than free PTX or the PPa@PTX-C-C NPs to suppress the growth of 4 T1 tumors.Therefore,this novel oxidation-strengthened disulfide-bridged prodrug-nanosystem has a great potential in the enhanced efficacy of cancer synergetic photochemotherapy.
基金supported by the National Natural Science Foundation of China,Nos.31601175(to YL),81803508(to KZ),82074056(to JY)the Natural Science Foundation of Liaoning Province of China,No.20180550335(to YL)the Scientific Research Project of Educational Commission of Liaoning Province of China,No.201610163L22(to YL)。
文摘Adolescent binge drinking leads to long-lasting disorders of the adult central nervous system,particularly aberrant hippocampal neurogenesis.In this study,we applied in vivo fluorescent tracing using NestinCreERT2::Rosa26-tdTomato mice and analyzed the endogenous neurogenesis lineage progression of neural stem cells(NSCs)and dendritic spine formation of newborn neurons in the subgranular zone of the dentate gyrus.We found abnormal orientation of tamoxifen-induced tdTomato+(tdTom^(+))NSCs in adult mice 2 months after treatment with EtOH(5.0 g/kg,i.p.)for 7 consecutive days.EtOH markedly inhibited tdTom^(+)NSCs activation and hippocampal neurogenesis in mouse dentate gyrus from adolescence to adulthood.EtOH(100 mM)also significantly inhibited the proliferation to 39.2%and differentiation of primary NSCs in vitro.Adult mice exposed to EtOH also exhibited marked inhibitions in dendritic spine growth and newborn neuron maturation in the dentate gyrus,which was partially reversed by voluntary running or inhibition of the mammalian target of rapamycinenhancer of zeste homolog 2 pathway.In vivo tracing revealed that EtOH induced abnormal orientation of tdTom+NSCs and spatial misposition defects of newborn neurons,thus causing the disturbance of hippocampal neurogenesis and dendritic spine remodeling in mice.
基金supported by Postdoctoral Science Foundation of China 2017M611268
文摘In the present paper, chiral mesoporous silica nano-cocoon(A-CMSN) functionalized with amino group was synthesized, and its loading and release of indomethacin(IMC), a poorly soluble drug, was studied. Due to the use of chiral anionic surfactants as a template, ACMSN possessed 2D hexagonal nano-cocoon morphology with curled channels on its surface, which was quite different from another 2D hexagonal mesoporous silica nanoparticles(MCM-41) with straightway channels. After being loaded into the two silica carriers by hydrogen bond, crystalline IMC converted to amorphous form, leading to the improved drug dissolution. And IMC loading capacity of A-CMSN was higher than MCM-41 because curled loading process originating from curvature chiral channels can hold more drug molecules. Compared with IMC, IMC loaded A-CMSN presented obviously fast release throughout the in vitro release experiment, while IMC loaded MCM-41 released faster than IMC at the initial 5 h then showed controlled slow release afterwards, which was closely related to the mesoporous silica nanoparticles and different channel mesostructures of these two carriers. A-CMSN possessed nano-cocoon morphology with curled 2D hexagonal channel and its channel length was shorter than MCM-41, therefore IMC molecules can easily get rid of the constraint of A-CMSN then to be surrounded by dissolution medium.
基金financially supported by the National Natural Science Foundation of China(21777111)。
文摘The use of fiber as a catalyst carrier to construct heterogeneous catalysts with good catalytic activity and recycling performance has received wide attention.In this study,three phenylboronic acid functionalized polyacrylonitrile fiber(PANF)catalysts were synthesized by amination and quaternization.Fourier transform infrared spectroscopy,X-ray diffractometry,scanning electron microscopy,and X-ray photoelectron spectroscopy were used to verify the successful grafting of phenylboronic acid and the structural integrity of the fiber catalyst after recycling.The activity of the catalysts was explored with the Friedel–Crafts alkylation between indole and aromatic aldehydes.The results indicate that the synthesized catalyst(PANp-BAF)in which the phenylboronic acid functional group was linked at the para position,exhibited the highest catalytic activity for the Friedel–Crafts alkylation.The substrate scope experiments confirmed that the catalyst has outstanding catalytic activity for most aromatic aldehydes,especially for those containing moderate electron donating groups.Moreover,the catalyst can be reused eight times in water without significant decrease in its catalytic activity.Further,the scale-up experiment confirmed that the fiber catalyst has a certain potential for industrial application.
基金Science and Technology Project of State Grid Corporation of China(Project No.5226SX18000F)Science and Technology Project of State Grid Shaanxi Electric Power Company(Project No.5226KY18002M).
文摘In gas insulation switch(GIS)substation,secondary devices such as linemonitoring devices are placed in the switching field,and these electronic devices are vulnerable to transient electromagnetic interference caused by switching operation.In order to facilitate the measurement and research of electromagnetic disturbance data under different working conditions,a simulation test device is developed in this paper,which can be used to simulate electromagnetic disturbance of GIS substation sensor and secondary device port under switch operation.A four-channel parallel gas switch was designed,and the main characteristic parameters of electromagnetic disturbance generated by the simulation device were measured by using high-frequency pulse power supply as the excitation source.The comparison between the measured waveform and the measured disturbance characteristic parameters of GIS substation shows that it is in good agreement with the measured waveform characteristics,conforms to the basic characteristics of damped oscillation wave,and can be used in the secondary equipment port disturbance voltage coupling characteristics,protection measures evaluation and assessment method research.
基金supported by the Jilin Province Higher Education TeachingReform Research Project Funding(Contract No.2020285O73B005E).
文摘In the existing power system with a large-scale hydrogen storage system,there are problems such as low efficiency of electric-hydrogen-electricity conversion and single modeling of the hydrogen storage system.In order to improve the hydrogen utilization rate of hydrogen storage system in the process of participating in the power grid operation,and speed up the process of electric-hydrogen-electricity conversion.This article provides a detailed introduction to the mathematical and electrical models of various components of the hydrogen storage unit,and also establishes a charging and discharging efficiency model that considers the temperature and internal gas partial pressure of the hydrogen storage unit.These models are of great significance for studying and optimizing gas storage technology.Through these models,the performance of gas storage units can be better understood and improved.These studies are very helpful for improving energy storage efficiency and sustainable development.The factors affecting the charge-discharge efficiency of hydrogen storage units are analyzed.By integrating the models of each unit and considering the capacity degradation of the hydrogen storage system,we can construct an efficiency model for a large hydrogen storage system and power conversion system.In addition,the simulation models of the hydrogen production system and hydrogen consumption system were established in MATLAB/Simulink.The accuracy and effectiveness of the simulation model were proved by comparing the output voltage variation curve of the simulation with the polarization curve of the typical hydrogen production system and hydrogen consumption system.The results show that the charge-discharge efficiency of the hydrogen storage unit increases with the increase of operating temperature,and H2 and O2 partial voltage have little influence on the charge-discharge efficiency.In the process of power conversion system converter rectification operation,its efficiency decreases with the increase of temperature,while in the process of inverter operation,power conversion system efficiency increases with the increase of temperature.Combined with the efficiency of each hydrogen storage unit and power conversion system converter,the upper limit of the capacity loss of different hydrogen storage units was set.The optimal charge-discharge efficiency of the hydrogen storage system was obtained by using the Cplex solver at 36.46%and 66.34%.
文摘Interference cancellation scheme without feedback is proposed for X channels with four antennas at each user. Space-time codeword with Alamouti structure is designed for each user. Codewords are combined according a certain rule. The unwanted codewords are cancelled by linear operation on the received signals. Then, multi-user interference is mitigated by the orthogonal property of the Alamouti code. Comparing with the existing scheme for the same scene, feedback information is not required in the proposed scheme. So the transmission efficiency is improved.
基金supported by the National Natural Science Foundation of China(Grant No.52078009)the joint research project of the Wind Engineering Research Center at Tokyo Polytechnic University(JURC Grant No.24242008).
文摘Winter poses a high risk for spreading infectious respiratory diseases,particularly in classrooms,which are known hotspots for cross-infection.The health hazards in classrooms lacking mechanical ventilation systems often go unnoticed.To address this issue,we studied the risk of respiratory infection transmission in such environments during winter by assessing the spread of contaminants using computational fluid dynamics(CFD).We evaluated four common airflow setups(split-type air conditioner,open door,open window,and both door and window open)in classrooms without mechanical ventilation.Our findings indicate that while split air conditioners provide optimal thermal comfort,they significantly increase exposure risk.Conversely,simply opening a door can effectively balance thermal comfort with a reduced exposure risk—particularly when the infected individual is near the door,leading to a minimal 0.01%average intake fraction.Furthermore,under varying ventilation scenarios,the sensitivity of exposure risk to location changes of infected individuals differs significantly.Specifically,when a split-type air conditioner is used,occupant exposure is largely unaffected by changes in the location of the infected individual.However,the exposure risk becomes highly sensitive to location changes of infected individuals when a door or window is used for ventilation.Strategic positioning of the infected individual can decrease indoor exposure risk by up to 94%with the door open and 67%with the window open.Additionally,when the door and window are both open,the dependency of occupant exposure on the location of the infected individual decreases.In this case,the exposure risk for indoor occupants is low,regardless of the position of the infected individual.
基金supported by the National Natural Science Foundation of China(Grant No.41925022)。
文摘Climate change in the Arctic serves as a pivotal indicator of alterations in the global climate system,with clouds playing an essential role in regulating the surface radiative energy balance in the Arctic.Elucidating the patterns of Arctic cloud variability and the underlying mechanisms is of paramount scientific importance for understanding Arctic climate change.Spatiotemporal analysis of Arctic cloud characteristics reveals that since the onset of the 21st century,low clouds have predominantly comprised the Arctic summer cloud fraction(approximately 60%),followed by middle clouds(approximately 30%).The total-cloud fraction has exhibited a marked increasing trend,especially in the Beaufort Sea and Chukchi Sea(0.45%/yr).An attribution analysis suggests that the changes in the Arctic cloud fraction are chiefly driven by trends in two atmospheric circulation modes:The Arctic Oscillation(AO)and the Arctic dipole anomaly(DA).During positive phases of the AO,the cloud fraction increases across all Arctic basins.Conversely,in the positive phases of the DA,the cloud fraction decreases in the Beaufort Sea,Chukchi Sea,and Greenland Sea,whereas it increases in the East Siberian Sea,Kara Sea,and Barents Sea,indicating an“east-west”dipole distribution.Since 2000,the AO has been on an upward trend,whereas the DA has been declining.The combined effect of these two modes has resulted in a significant increase in the cloud fraction within the Beaufort Sea region.Further examination of cloud radiative effects indicates that an increase in the cloud fraction intensifies both longwave warming and shortwave cooling effects,leading to an overall net negative radiative effect.Analyzing the long-term trends in Arctic summer clouds enhances our comprehension of Arctic climate change.
基金This research was supported by National Natural Science Foundation of China(Nos.82273874 and 82404561)Liaoning Revitalization Talents Program(No.XLYC22202019)+4 种基金the China National Postdoctoral Program for Innovative Talents(No.BX20240233)the Postdoctoral Fellowship Program(Grade B)of China Postdoctoral Science Foundation(No.GZB20240179)the China Postdoctoral Science Foundation(No.2023MD744230)Doctoral Scientific Research Launching Fund Project of Liaoning province(No.2024-BS-075)Prospective Basic research project of 2024 Scientific Research Project of Liaoning Department of Education(No.LJ212410163042).
文摘The tumor microenvironment-sensitive prodrug-based nanoparticles(NPs)have emerged as a promising drug delivery system(DDS).The shape of these particles plays a crucial role in their in vivo behavior.However,non-spherical organic NPs are rarely reported due to the inherent flexibility and variability of organic molecules.Herein,we fabricate reduction-sensitive prodrug NPs and explore the impact of their morphology properties on their in vivo fate.Prodrugs are self-assembled into spherical NPs with distearoyl phosphoethanolamine-PEG2000(DSPE-PEG2k),or into rod-shaped NPs with D-a-tocopherol polyethylene glycol 2000 succinate(TPGS2k)due to the stronger binding energy.In comparison with spherical NPs,the endocytosis of rod-shaped NPs predominantly relies on caveolae-mediated pathways rather than clathrin-mediated ones,potentially avoiding degradation by lysosomes.Additionally,the rod-shaped NPs exhibit prolonged circulation time,increased tumor accumulation,and enhanced antitumor ability.Our current findings reveal the significant effect of particle shape on the behavior of prodrug NPs and introduce a novel paradigm for high-efficacy cancer therapy of prodrug NPs.
