In this paper,tannic acid(TA)and Fe~(3+)were added to form a layer of metal-polyphenol network structure on the surface of the nanoparticles which were fabricated by zein and carbon quantum dots(CQDs)encapsulating phl...In this paper,tannic acid(TA)and Fe~(3+)were added to form a layer of metal-polyphenol network structure on the surface of the nanoparticles which were fabricated by zein and carbon quantum dots(CQDs)encapsulating phlorotannins(PTN).pH-Responsive nanoparticles were prepared successfully(zein-PTN-CQDs-Fe-~Ⅲ).Further,the formation of composite nanoparticles was confirmed by a series of characterization methods.The zeta-potential and Fourier transform infrared spectroscopy data proved that electrostatic interaction and hydrogen bonding are dominant forces to form nanoparticles.The encapsulation efficiency(EE)revealed that metal-polyphenol network structure could improve the EE of PTN.Thermogravimetric analysis and differential scanning calorimetry experiment indicated the thermal stability of zein-PTN-CQDs-Fe~Ⅲnanoparticles increased because of metal-polyphenol network structure.The pH-responsive nanoparticles greatly increased the release rate of active substances and achieved targeted release.展开更多
Herein,the co-pyrolysis reaction characteristics of corn straw(CS)and bituminous coal in the presence of ilmenite oxygen carriers(OCs)are investigated via thermogravimetry coupled with mass spectrometry.The results re...Herein,the co-pyrolysis reaction characteristics of corn straw(CS)and bituminous coal in the presence of ilmenite oxygen carriers(OCs)are investigated via thermogravimetry coupled with mass spectrometry.The results reveal that the participation of OCs weakens the devolatilization intensity of co-pyrolysis.When the CS blending ratio is<50%,the mixed fuel exhibits positive synergistic effects.The fitting results according to the Coats-Redfern integral method show that the solid-solid interaction between OCs and coke changes the reaction kinetics,enhancing the co-pyrolysis reactivity at the high-temperature zone(750-950C).The synergistic effect is most prominent at a 30%CS blending ratio,with copyrolysis activation energy in the range of 26.35-40.57 kJ·mol^(-1).展开更多
Objective:Hemophilia carriers(HCs),who are heterozygous for mutations in the clotting factor VIII/clotting factor IX gene(F8 or F9),may have a wide range of clotting factor levels,from very low,similar to afflicted ma...Objective:Hemophilia carriers(HCs),who are heterozygous for mutations in the clotting factor VIII/clotting factor IX gene(F8 or F9),may have a wide range of clotting factor levels,from very low,similar to afflicted males,to the upper limit of normal,and may experience mental health issues.The purpose of this study was to provide genetic information on mothers of hemophilia patients and to understand the clotting factor activity and phenotype of HCs.Additionally,we aimed to investigate the mental health status of HCs in China.Methods:A total of 127 hemophilia mothers,including 93 hemophilia A(HA)mothers and 34 hemophilia B(HB)mothers,were enrolled in this study.Long distance PCR,multiplex PCR,and Sanger sequencing were used to analyze mutations in F8 or F9.Coagulation factor activity was detected by a one-stage clotting assay.The Symptom Checklist 90(SCL-90,China/Mandarin version)was given to HCs at the same time to assess their mental health.Results:A total of 90.6%of hemophilia mothers were diagnosed genetically as carriers,with inversion in intron 22 and missense mutations being the most common mutation types in HA and HB carriers,respectively.The median clotting factor level in carriers was 0.74 IU/mL(ranging from 0.09 to 1.74 IU/mL)compared with 1.49 IU/mL(ranging from 0.93 to 1.89 IU/mL)in noncarriers,of which 14.3%of HCs had clotting factor levels of 0.40 IU/mL or below.A total of 53.8%(7/13)of HA carriers with low clotting factor levels(less than 0.50 IU/mL)had a history of bleeding,while none of the HB carriers displayed a bleeding phenotype.The total mean score and the global severity index of the SCL-90 for surveyed HCs were 171.00(±60.37)and 1.78(±0.59),respectively.A total of 67.7%of the respondents had psychological symptoms,with obsessive-compulsive disorder being the most prevalent and severe.The pooled estimates of all nine factors were significantly higher than those in the general population(P<0.05).Conclusions:The detection rate of gene mutations in hemophilia mothers was 90.6%,with a median clotting factor level of 0.74 IU/mL,and 14.3%of HCs had a clotting factor level of 0.40 IU/mL or below.A history of bleeding was present in 41.2%of HCs with low clotting factor levels(less than 0.50 IU/mL).Additionally,given the fragile mental health status of HCs in China,it is critical to develop efficient strategies to improve psychological well-being.展开更多
Quasi-2D Dion-Jacobson(DJ)tin halide perovskite has attracted much attention due to its elimination of Van der Waals gap and enhanced environmental stability.However,the bulky organic spacers usually form a natural qu...Quasi-2D Dion-Jacobson(DJ)tin halide perovskite has attracted much attention due to its elimination of Van der Waals gap and enhanced environmental stability.However,the bulky organic spacers usually form a natural quantum well structure,which brings a large quantum barrier and poor film quality,further limiting the carrier transport and device performance.Here,we designed three organic spacers with different chain lengths(ethylenediamine(EDA),1,3-propanediamine(PDA),and 1,4-butanediamine(BDA))to investigate the quantum barrier dependence.Theoretical and experimental characterizations indicate that EDA with short chain can reduce the lattice distortion and dielectric confinement effect,which is beneficial to the effective dissociation of excitons and the inhibition of trap-free non-radiative relaxation.In addition,EDA cation shows strong interaction with the inorganic octahedron,realizing large aggregates in precursor solution and high-quality films with improved structural stability.Furthermore,femtosecond transient absorption proves that EDA cations can also weaken the formation of small n-phases with large quantum barrier to achieve effective carrier transport between different nphases.Finally,the quasi-2D DJ(EDA)FA_(9)Sn_(10)I_(31)solar cells achieves a 7.07%power conversion efficiency with good environment stability.Therefore,this work sheds light on the regulation of the quantum barrier and carrier transport through the chain length of organic spacer for qua si-2D DJ lead-free perovskites.展开更多
Cu2ZnSn(S,Se)4(CZTSSe)solar cells have resource distribution and economic advantages.The main cause of their low efficiency is carrier loss resulting from recombination of photo-generated electron and hole.To overcome...Cu2ZnSn(S,Se)4(CZTSSe)solar cells have resource distribution and economic advantages.The main cause of their low efficiency is carrier loss resulting from recombination of photo-generated electron and hole.To overcome this,it is important to understand their electron-hole behavior characteristics.To determine the carrier separation characteristics,we measured the surface potential and the local current in terms of the absorber depth.The elemental variation in the intragrains(IGs)and at the grain boundaries(GBs)caused a band edge shift and bandgap(Eg)change.At the absorber surface and subsurface,an upward Ec and Ev band bending structure was observed at the GBs,and the carrier separation was improved.At the absorber center,both upward Ec and Ev and downward Ec-upward Ev band bending structures were observed at the GBs,and the carrier separation was degraded.To improve the carrier separation and suppress carrier recombination,an upward Ec and Ev band bending structure at the GBs is desirable.展开更多
We measure the time-resolved terahertz spectroscopy of GeSn thin film and studied the ultrafast dynamics of its photo-generated carriers.The experimental results show that there are photo-generated carriers in GeSn un...We measure the time-resolved terahertz spectroscopy of GeSn thin film and studied the ultrafast dynamics of its photo-generated carriers.The experimental results show that there are photo-generated carriers in GeSn under femtosecond laser excitation at 2500 nm,and its pump-induced photoconductivity can be explained by the Drude–Smith model.The carrier recombination process is mainly dominated by defect-assisted Auger processes and defect capture.The firstand second-order recombination rates are obtained by the rate equation fitting,which are(2.6±1.1)×10^(-2)ps^(-1)and(6.6±1.8)×10^(-19)cm^(3)·ps^(-1),respectively.Meanwhile,we also obtain the diffusion length of photo-generated carriers in GeSn,which is about 0.4μm,and it changes with the pump delay time.These results are important for the GeSn-based infrared optoelectronic devices,and demonstrate that Ge Sn materials can be applied to high-speed optoelectronic detectors and other applications.展开更多
A Diesel Particulate Filter(DPF)is a critical device for diesel engine exhaust products treatment.When using active-regeneration purification methods,on the one hand,a spatially irregular gas flow can produce relative...A Diesel Particulate Filter(DPF)is a critical device for diesel engine exhaust products treatment.When using active-regeneration purification methods,on the one hand,a spatially irregular gas flow can produce relatively high local temperatures,potentially resulting in damage to the carrier;On the other hand,the internal temperature field can also undergo significant changes contributing to increase this risk.This study explores the gas flow uniformity in a DPF carrier and the related temperature behavior under drop-to-idle(DTI)condition by means of bench tests.It is shown that the considered silicon carbide carrier exhibits good flow uniformity,with a temperature deviation of no more than 2%with respect to the same radius measurement point at the outlet during the regeneration stage.In the DTI test,the temperature is relatively high within r/2 near the outlet end,where the maximum temperature peak occurs,and the maximum radial temperature gradient is located between r/2 and the edge.Both these quantities grow as the soot load increases,thereby making the risk of carrier burnout greater.Finally,it is shown that the soot load limit of the silicon carbide DPF can be extended to 11 g/L,which reduces the frequency of active regeneration by approximately 40%compared to a cordierite DPF.展开更多
It is a challenge to coordinate carrier-kinetics performance and the redox capacity of photogenerated charges synchronously at the atomic level for boosting photocatalytic activity.Herein,the atomic Ni was introduced ...It is a challenge to coordinate carrier-kinetics performance and the redox capacity of photogenerated charges synchronously at the atomic level for boosting photocatalytic activity.Herein,the atomic Ni was introduced into the lattice of hexagonal ZnIn_(2)S_(4) nanosheets(Ni/ZnIn_(2)S_(4))via directionalsubstituting Zn atom with the facile hydrothermal method.The electronic structure calculations indicate that the introduction of Ni atom effectively extracts more electrons and acts as active site for subsequent reduction reaction.Besides the optimized light absorption range,the elevation of Efand ECBendows Ni/ZnIn_(2)S_(4) photocatalyst with the increased electron concentration and the enhanced reduction ability for surface reaction.Moreover,ultrafast transient absorption spectroscopy,as well as a series of electrochemical tests,demonstrates that Ni/ZnIn_(2)S_(4) possesses 2.15 times longer lifetime of the excited charge carriers and an order of magnitude increase for carrier mobility and separation efficiency compared with pristine ZnIn_(2)S_(4).These efficient kinetics performances of charge carriers and enhanced redox capacity synergistically boost photocatalytic activity,in which a 3-times higher conversion efficiency of nitrobenzene reduction was achieved upon Ni/ZnIn_(2)S_(4).Our study not only provides in-depth insights into the effect of atomic directional-substitution on the kinetic behavior of photogenerated charges,but also opens an avenue to the synchronous optimization of redox capacity and carrier-kinetics performance for efficient solar energy conversion.展开更多
Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and ...Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and mitigate climate change.In this process,a metal oxide is used as oxygen carrier in a dual fluidized bed to generate clean CO_(2) via combustion of biomass.Most commonly,natural ores or synthetic materials are used as oxygen carrier whereas both must meet special requirements for the conversion of solid fuels.Synthetic oxygen carriers are characterized by higher reactivity at the expense of higher costs versus the lower-cost natural ores.To determine the viability of both possibilities,a techno-economic comparison of a synthetic material based on manganese,iron,and copper to the natural ore ilmenite was conducted.The synthetic oxygen carrier was characterized and tested in a pilot plant,where high combustion efficiencies up to 98.4%and carbon capture rates up to 98.5%were reached.The techno-economic assessment resulted in CO_(2) capture costs of 75 and 40€/tCO_(2) for the synthetic and natural ore route respectively,whereas a sensitivity analysis showed the high impact of production costs and attrition rates of the synthetic material.The synthetic oxygen carrier could break even with the natural ore in case of lower production costs and attrition rates,which could be reached by adapting the production process and recycling material.By comparison to state-of-the-art technologies,it is demonstrated that both routes are viable and the capture cost of CO_(2) could be reduced by implementing the chemical looping combustion technology.展开更多
BACKGROUND The precise role of mitochondrial carrier homolog 2(MTCH2)in promoting malignancy in gastric mucosal cells and its involvement in gastric cancer cell metastasis have not been fully elucidated.AIM To determi...BACKGROUND The precise role of mitochondrial carrier homolog 2(MTCH2)in promoting malignancy in gastric mucosal cells and its involvement in gastric cancer cell metastasis have not been fully elucidated.AIM To determine the role of MTCH2 in gastric cancer.METHODS We collected 65 samples of poorly differentiated gastric cancer tissue and adjacent tissues,constructed MTCH2-overexpressing and MTCH2-knockdown cell models,and evaluated the proliferation,migration,and invasion of human gastric epithelial cells(GES-1)and human gastric cancer cells(AGS)cells.The mito-chondrial membrane potential(MMP),mitochondrial permeability transformation pore(mPTP)and ATP fluorescence probe were used to detect mitochondrial function.Mitochondrial function and ATP synthase protein levels were detected via Western blotting.RESULTS The expression of MTCH2 and ATP2A2 in gastric cancer tissues was significantly greater than that in adjacent tissues.Overexpression of MTCH2 promoted colony formation,invasion,migration,MMP expression and ATP production in GES-1 and AGS cells while upregulating ATP2A2 expression and inhibiting cell apoptosis;knockdown of MTCH2 had the opposite effect,promoting overactivation of the mPTP and promoting apoptosis.CONCLUSION MTCH2 can increase the malignant phenotype of GES-1 cells and promote the proliferation,invasion,and migration of gastric cancer cells by regulating mitochondrial function,providing a basis for targeted therapy for gastric cancer cells.展开更多
The hybrid carrier(HC)system rooted in the carrier fusion concept is gradually garnering attention.In this paper,we study the extended hybrid carrier(EHC)multiple access scheme to ensure reliable wireless communicatio...The hybrid carrier(HC)system rooted in the carrier fusion concept is gradually garnering attention.In this paper,we study the extended hybrid carrier(EHC)multiple access scheme to ensure reliable wireless communication.By employing the EHC modulation,a power layered multiplexing framework is realized,which exhibits enhanced interference suppression capability owing to the more uniform energy distribution design.The implementation method and advantage mechanism are explicated respectively for the uplink and downlink,and the performance analysis under varying channel conditions is provided.In addition,considering the connectivity demand,we explore the non-orthogonal multiple access(NOMA)method of the EHC system and develop the EHC sparse code multiple access scheme.The proposed scheme melds the energy spread superiority of EHC with the access capacity of NOMA,facilitating superior support for massive connectivity in high mobility environments.Simulation results have verified the feasibility and advantages of the proposed scheme.Compared with existing HC multiple access schemes,the proposed scheme exhibits robust bit error rate performance and can better guarantee multiple access performance in complex scenarios of nextgeneration communications.展开更多
A pH-responsive conjugate based 10-hydroxycamptothecin-thiosemicarbazide-polyethene glycol 2000 (10-HCPT-hydro-PEG) nano-micelles were prepared in our previous study. In the present study, ultra-performance liquid chr...A pH-responsive conjugate based 10-hydroxycamptothecin-thiosemicarbazide-polyethene glycol 2000 (10-HCPT-hydro-PEG) nano-micelles were prepared in our previous study. In the present study, ultra-performance liquid chromatography (UPLC-MS) method is developed to investigate its pharmacokinetics and biodistribution in tumor bearing mice. The results demonstrated that the conjugate circulated for a much longer time in the blood circulation system than commercial 10-HCPT injection, and bioavailability was significantly improved compared with 10-HCPT. In vivo biodistribution study showed that the conjugate could enhance the targeting and residence time in tumor site.展开更多
Converting polyethylene terephthalate(PET)wastes to its monomer and valuable chemicals via ecofriendly chemical method is still a challenge task.Previously,phase transfer catalysts used for alkaline hydrolysis were so...Converting polyethylene terephthalate(PET)wastes to its monomer and valuable chemicals via ecofriendly chemical method is still a challenge task.Previously,phase transfer catalysts used for alkaline hydrolysis were soluble in reaction media and hardly separated after reaction.Here,we reported several pH-responsive catalysts combined alkyl quaternary ammonium units with heteropolyacid anion for achieving stepwise product/catalyst separation and catalyst recycling.The properties of homogeneous/heterogeneous transfer behavior allow catalyst to be easily separated from reaction media by adjusting of pH value.Among them,[C_(16)H_(33)N(CH_(3))_(3)]_(3)PW_(12)O_(40)(abbreviated as[CTA]_(3)PW)exhibits the highest activity and the most suitable pH responsive values.Such a pH triggered switchable catalytic system not only shows good performance for depolymerization of pure PET,but also some real PET wastes such as coloured trays and PE/PET complex films could be completely degraded into terephthalic acid.Additionally,the reaction kinetics and activation energy of PET alkaline hydrolysis also studied with and without pH-responsive[CTA]_(3)PW.展开更多
Due to the negative roles of tumor microenvironment(TME)in compromising therapeutic responses of various cancer therapies,it is expected that modulation of TME may be able to enhance the therapeutic responses during c...Due to the negative roles of tumor microenvironment(TME)in compromising therapeutic responses of various cancer therapies,it is expected that modulation of TME may be able to enhance the therapeutic responses during cancer treatment.Herein,we develop a concise strategy to prepare pH-responsive nanoparticles via the CaCO3-assisted double emulsion method,thereby enabling effective co-encapsulation of both doxorubicin(DOX),an immunogenic cell death(ICD)inducer,and alkylated NLG919(aNLG919),an inhibitor of indoleamine 2,3-dioxygenase 1(IDO1).The obtained DOX/aNLG919-loaded CaCO3 nanoparticles(DNCaNPs)are able to cause effective ICD of cancer cells and at the same time restrict the production of immunosuppressive kynurenine by inhibiting IDO1.Upon intravenous injection,such DNCaNPs show efficient tumor accumulation,improved tumor penetration of therapeutics and neutralization of acidic TME.As a result,those DNCaNPs can elicit effective anti-tumor immune responses featured in increased density of tumor-infiltrating CD8+cytotoxic T cells as well as depletion of immunosuppressive regulatory T cells(Tregs),thus effectively suppressing the growth of subcutaneous CT26 and orthotopic 4T1 tumors on the Balb/c mice through combined chemotherapy&immunotherapy.This study presents a compendious strategy for construction of pH-responsive nanoparticles,endowing significantly enhanced chemo-immunotherapy of cancer by overcoming the immunosuppressive TME.展开更多
Bulk graphene nanofilms feature fast electronic and phonon transport in combination with strong light-matter interaction and thus have great potential for versatile applications,spanning from photonic,electronic,and o...Bulk graphene nanofilms feature fast electronic and phonon transport in combination with strong light-matter interaction and thus have great potential for versatile applications,spanning from photonic,electronic,and optoelectronic devices to charge-stripping and electromagnetic shielding,etc.However,large-area flexible close-stacked graphene nanofilms with a wide thickness range have yet to be reported.Here,we report a polyacrylonitrile-assisted’substrate replacement’strategy to fabricate large-area free-standing graphene oxide/polyacrylonitrile nanofilms(lateral size~20 cm).Linear polyacrylonitrile chains-derived nanochannels promote the escape of gases and enable macro-assembled graphene nanofilms(nMAGs)of 50-600 nm thickness following heat treatment at 3,000℃.The uniform nMAGs exhibit 802-1,540 cm^(2)V-1s-1carrier mobility,4.3-4.7 ps carrier lifetime,and>1,581 W m^(-1)K^(-1)thermal conductivity(n MAG-assembled 10μm-thick films,mMAGs).nMAGs are highly flexible and show no structure damage even after 1.0×10^(5)cycles of folding-unfolding.Furthermore,n MAGs broaden the detection region of graphene/silicon heterojunction from near-infrared to mid-infrared and demonstrate higher absolute electromagnetic interference(EMI)shielding effectiveness than state-of-the-art EMI materials of the same thickness.These results are expected to lead to the broad applications of such bulk nanofilms,especially as micro/nanoelectronic and optoelectronic platforms.展开更多
Preparation of polymer microspheres from naturally occurring resource is a challenge.Here,a rosin-based polyol(RAG)was used to prepare polyurethane resin(RPU)firstly,and then act as both self-assembled precursor and e...Preparation of polymer microspheres from naturally occurring resource is a challenge.Here,a rosin-based polyol(RAG)was used to prepare polyurethane resin(RPU)firstly,and then act as both self-assembled precursor and emulsifier,rosin based polyurethane microspheres(RPUMs)were prepared.In the process of self-emulsification,the RPU formed vesicles by self-assembly.The outer shell of the vesicle consisted of hydrophilic segments,while the inner shell contained the hydrophobic phase.After cross-linking the RPU and removal of the solvent in the core,the porous-hollow microspheres with pH-sensitive were obtained.The microspheres were characterized by optical microscope(OM),scanning electron microscopy(SEM)and transmission electron microscope(TEM).The effect of type and amount of the hydrophilic chain extender,and solvent on the morphology,particle size and distribution,and buffer volume of the microspheres were determined.The best conditions for synthetic RPUMs were as follows:n_(NCO)/n_(OH)=1,n_(RAG):n_(1-(2-hydroxyethyl)piperazine)=4:6,with azodiisobutyronitrile level of 1.0 wt.%,based on reactive monomers,mixing speed of both emulsification and polymerization at 400 r·min-1,the RPUMs synthesized had porous-hollow structure with a buffer volume of 1.6 mL.展开更多
The oxygen distribution and evolution within the oxygen carrier exert significant influence on chemical looping processes.This paper describes the influence of oxygen bulk diffusion within FeVO4 oxygen carrier pellets...The oxygen distribution and evolution within the oxygen carrier exert significant influence on chemical looping processes.This paper describes the influence of oxygen bulk diffusion within FeVO4 oxygen carrier pellets on the chemical looping oxidative propane dehydrogenation(CL-ODH).During CL-ODH,the oxygen concentration at the pellet surface initially decreased and then maintained stable before the final decrease.At the stage with the stable surface oxygen concentration,the reaction showed a stable C3H6 formation rate and high C3H6 selectivity.Therefore,based on Fick’s second law,the oxygen distribution and evolution in the oxygen carrier at this stage were further analyzed.It was found that main reactions of selective oxidation and over-oxidation were controlled by the oxygen bulk diffusion.C3H8 conversion rate kept decreasing during this stage due to the decrease of the oxygen flux caused by the decline of oxygen gradient within the oxygen carrier,while C3H6 selectivity increased due to the decrease of overoxidation.In addition,reaction rates could increase with the propane partial pressure due to the increase of the oxygen gradient within the oxygen carrier until the bulk transfer reached its limit at higher propane partial pressure.This study provides fundamental insights for the diffusion-controlled chemical looping reactions.展开更多
Targeted photodynamic therapy(TPDT)based on the photosensitizers responsive for tumor micr oenvironment is promising because of the better anti-tumor effect and less phototoxicity against normal tissue than the tradit...Targeted photodynamic therapy(TPDT)based on the photosensitizers responsive for tumor micr oenvironment is promising because of the better anti-tumor effect and less phototoxicity against normal tissue than the traditional PDT.Nanoparticle based stimuli responsive photo-sensitizers have been widely explored for TPDT.Based on the acidic microenvironments in solid tumors,an ultrasmall pH-responsive silicon phthalocyanine nanomicelle(PSN)(smaller than 10 nm)was designed for selective PDT of tumor.PSN had high drug loading efficacy(more than 28%)and exhibited morphological transitions,enhanced fuorescence and improved singlet∞x-ygen yield under acidic environments.PSN was renal dlearable and could rapidly accumulate and be retained at tumor sites,achieving a tumor-inhibiting ffect better than phthalocyanine micelle without pH response.Tumors of mice treated with PSN for PDT were completely ablated without recurrence.Thus,we have developed a phthalocyanine-based pH responsive micelle with excellent tumor targeting ability,which is expected to realize the selective PDT of tumor.展开更多
Amorphous solid dispersion(ASD)is one of the most effective approaches for delivering poorly soluble drugs.In ASDs,polymeric materials serve as the carriers in which the drugs are dispersed at the molecular level.To p...Amorphous solid dispersion(ASD)is one of the most effective approaches for delivering poorly soluble drugs.In ASDs,polymeric materials serve as the carriers in which the drugs are dispersed at the molecular level.To prepare the solid dispersions,there are many polymers with various physicochemical and thermochemical characteristics available for use in ASD formulations.Polymer selection is of great importance because it influences the stability,solubility and dissolution rates,manufacturing process,and bioavailability of the ASD.This review article provides a comprehensive overview of ASDs from the perspectives of physicochemical characteristics of polymers,formulation designs and preparation methods.Furthermore,considerations of safety and regulatory requirements along with the studies recommended for characterizing and evaluating polymeric carriers are briefly discussed.展开更多
The defects from electron transport layer,perovskite layer and their interface would result in carrier nonradiative recombination losses.Poor buried interfacial contact is detrimental to charge extraction and device s...The defects from electron transport layer,perovskite layer and their interface would result in carrier nonradiative recombination losses.Poor buried interfacial contact is detrimental to charge extraction and device stability.Here,we report a bottom-up holistic carrier management strategy induced synergistically by multiple chemical bonds to minimize bulk and interfacial energy losses for high-performance perovskite photovoltaics.4-trifluoromethyl-benzamidine hydrochloride(TBHCl)containing–CF_(3),amidine cation and Cl^(-)is in advance incorporated into SnO_(2)colloid solution to realize bottom-up modification.The synergistic effect of multiple functional groups and multiple-bond-induced chemical interaction are revealed theoretically and experimentally.F and Cl^(-)can passivate oxygen vacancy and/or undercoordinated Sn^(4+)defects by coordinating with Sn^(4+).The F can suppress cation migration and modulate crystallization via hydrogen bond with FA^(+),and can passivate lead defects by coordinating with Pb^(2+).The–NH_(2)–C=NH^(+)_(2)and Cl^(-)can passivate cation and anion vacancy defects through ionic bonds with perovskites,respectively.Through TBHCl modification,the suppression of agglomeration of SnO_(2)nanoparticles,bulk and interfacial defect passivation,and release of tensile strains of perovskite films are demonstrated,which resulted in a PCE enhancement from 21.28%to 23.40%and improved stability.With post-treatment,the efficiency is further improved to 23.63%.展开更多
基金supported by the National Key R&D Program of China (2018YFD0901106)the Wenzhou Major Science and Technology Project (ZN2021002)the Ningbo“3315 series program”for high-level talents (2020B-34-G)。
文摘In this paper,tannic acid(TA)and Fe~(3+)were added to form a layer of metal-polyphenol network structure on the surface of the nanoparticles which were fabricated by zein and carbon quantum dots(CQDs)encapsulating phlorotannins(PTN).pH-Responsive nanoparticles were prepared successfully(zein-PTN-CQDs-Fe-~Ⅲ).Further,the formation of composite nanoparticles was confirmed by a series of characterization methods.The zeta-potential and Fourier transform infrared spectroscopy data proved that electrostatic interaction and hydrogen bonding are dominant forces to form nanoparticles.The encapsulation efficiency(EE)revealed that metal-polyphenol network structure could improve the EE of PTN.Thermogravimetric analysis and differential scanning calorimetry experiment indicated the thermal stability of zein-PTN-CQDs-Fe~Ⅲnanoparticles increased because of metal-polyphenol network structure.The pH-responsive nanoparticles greatly increased the release rate of active substances and achieved targeted release.
基金support by the Key Research and Development Program of Ningxia Province of China(2018BCE01002)funded by the Joint Funds of the National Natural Science Foundation of China(U20A20124)the Natural Science Foundation Project of Ningxia(2022AAC01001).
文摘Herein,the co-pyrolysis reaction characteristics of corn straw(CS)and bituminous coal in the presence of ilmenite oxygen carriers(OCs)are investigated via thermogravimetry coupled with mass spectrometry.The results reveal that the participation of OCs weakens the devolatilization intensity of co-pyrolysis.When the CS blending ratio is<50%,the mixed fuel exhibits positive synergistic effects.The fitting results according to the Coats-Redfern integral method show that the solid-solid interaction between OCs and coke changes the reaction kinetics,enhancing the co-pyrolysis reactivity at the high-temperature zone(750-950C).The synergistic effect is most prominent at a 30%CS blending ratio,with copyrolysis activation energy in the range of 26.35-40.57 kJ·mol^(-1).
基金supported by Pfizer and the Haemophilia,Experience,Results,and Opportunities(HERO)Research Grant(Novo Nordisk).
文摘Objective:Hemophilia carriers(HCs),who are heterozygous for mutations in the clotting factor VIII/clotting factor IX gene(F8 or F9),may have a wide range of clotting factor levels,from very low,similar to afflicted males,to the upper limit of normal,and may experience mental health issues.The purpose of this study was to provide genetic information on mothers of hemophilia patients and to understand the clotting factor activity and phenotype of HCs.Additionally,we aimed to investigate the mental health status of HCs in China.Methods:A total of 127 hemophilia mothers,including 93 hemophilia A(HA)mothers and 34 hemophilia B(HB)mothers,were enrolled in this study.Long distance PCR,multiplex PCR,and Sanger sequencing were used to analyze mutations in F8 or F9.Coagulation factor activity was detected by a one-stage clotting assay.The Symptom Checklist 90(SCL-90,China/Mandarin version)was given to HCs at the same time to assess their mental health.Results:A total of 90.6%of hemophilia mothers were diagnosed genetically as carriers,with inversion in intron 22 and missense mutations being the most common mutation types in HA and HB carriers,respectively.The median clotting factor level in carriers was 0.74 IU/mL(ranging from 0.09 to 1.74 IU/mL)compared with 1.49 IU/mL(ranging from 0.93 to 1.89 IU/mL)in noncarriers,of which 14.3%of HCs had clotting factor levels of 0.40 IU/mL or below.A total of 53.8%(7/13)of HA carriers with low clotting factor levels(less than 0.50 IU/mL)had a history of bleeding,while none of the HB carriers displayed a bleeding phenotype.The total mean score and the global severity index of the SCL-90 for surveyed HCs were 171.00(±60.37)and 1.78(±0.59),respectively.A total of 67.7%of the respondents had psychological symptoms,with obsessive-compulsive disorder being the most prevalent and severe.The pooled estimates of all nine factors were significantly higher than those in the general population(P<0.05).Conclusions:The detection rate of gene mutations in hemophilia mothers was 90.6%,with a median clotting factor level of 0.74 IU/mL,and 14.3%of HCs had a clotting factor level of 0.40 IU/mL or below.A history of bleeding was present in 41.2%of HCs with low clotting factor levels(less than 0.50 IU/mL).Additionally,given the fragile mental health status of HCs in China,it is critical to develop efficient strategies to improve psychological well-being.
基金financially supported by the National Key Research and Development Program of China(2022YFE0118400)the National Natural Science Foundation of China(51702038)+1 种基金the Science&Technology Department of Sichuan Province(2020YFG0061)the Recruitment Program for Young Professionals。
文摘Quasi-2D Dion-Jacobson(DJ)tin halide perovskite has attracted much attention due to its elimination of Van der Waals gap and enhanced environmental stability.However,the bulky organic spacers usually form a natural quantum well structure,which brings a large quantum barrier and poor film quality,further limiting the carrier transport and device performance.Here,we designed three organic spacers with different chain lengths(ethylenediamine(EDA),1,3-propanediamine(PDA),and 1,4-butanediamine(BDA))to investigate the quantum barrier dependence.Theoretical and experimental characterizations indicate that EDA with short chain can reduce the lattice distortion and dielectric confinement effect,which is beneficial to the effective dissociation of excitons and the inhibition of trap-free non-radiative relaxation.In addition,EDA cation shows strong interaction with the inorganic octahedron,realizing large aggregates in precursor solution and high-quality films with improved structural stability.Furthermore,femtosecond transient absorption proves that EDA cations can also weaken the formation of small n-phases with large quantum barrier to achieve effective carrier transport between different nphases.Finally,the quasi-2D DJ(EDA)FA_(9)Sn_(10)I_(31)solar cells achieves a 7.07%power conversion efficiency with good environment stability.Therefore,this work sheds light on the regulation of the quantum barrier and carrier transport through the chain length of organic spacer for qua si-2D DJ lead-free perovskites.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Ministry of Science and ICT(No.2022M3J1A1085371)by the DGIST R&D programs of the Ministry of Science and ICT(23-ET-08 and 23-CoE-ET-01)supported by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2018R1A6A1A03025340).
文摘Cu2ZnSn(S,Se)4(CZTSSe)solar cells have resource distribution and economic advantages.The main cause of their low efficiency is carrier loss resulting from recombination of photo-generated electron and hole.To overcome this,it is important to understand their electron-hole behavior characteristics.To determine the carrier separation characteristics,we measured the surface potential and the local current in terms of the absorber depth.The elemental variation in the intragrains(IGs)and at the grain boundaries(GBs)caused a band edge shift and bandgap(Eg)change.At the absorber surface and subsurface,an upward Ec and Ev band bending structure was observed at the GBs,and the carrier separation was improved.At the absorber center,both upward Ec and Ev and downward Ec-upward Ev band bending structures were observed at the GBs,and the carrier separation was degraded.To improve the carrier separation and suppress carrier recombination,an upward Ec and Ev band bending structure at the GBs is desirable.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12004067,11974070,62027807,and 52272137)the National Key R&D Program of China(Grant No.2022YFA1403000)。
文摘We measure the time-resolved terahertz spectroscopy of GeSn thin film and studied the ultrafast dynamics of its photo-generated carriers.The experimental results show that there are photo-generated carriers in GeSn under femtosecond laser excitation at 2500 nm,and its pump-induced photoconductivity can be explained by the Drude–Smith model.The carrier recombination process is mainly dominated by defect-assisted Auger processes and defect capture.The firstand second-order recombination rates are obtained by the rate equation fitting,which are(2.6±1.1)×10^(-2)ps^(-1)and(6.6±1.8)×10^(-19)cm^(3)·ps^(-1),respectively.Meanwhile,we also obtain the diffusion length of photo-generated carriers in GeSn,which is about 0.4μm,and it changes with the pump delay time.These results are important for the GeSn-based infrared optoelectronic devices,and demonstrate that Ge Sn materials can be applied to high-speed optoelectronic detectors and other applications.
基金This work was supported by National Key R&D Program Project[Grant Number 2020YFB0106603]Provincial Major Scientific and Technological Innovation Project[Grant Number 2021CXGC010207-1]+2 种基金Shantui Engineering Machinery Intelligent Equipment Innovation and Entrepreneurship Community Innovation Project[Grant Number GTT2021105]Shandong Provincial Science and Technology SMEs Innovation Capacity Improvement Project[Grant Numbers 2021TSGC1334]Undergraduate School of Shandong University,China[Grant Number 2022Y155].
文摘A Diesel Particulate Filter(DPF)is a critical device for diesel engine exhaust products treatment.When using active-regeneration purification methods,on the one hand,a spatially irregular gas flow can produce relatively high local temperatures,potentially resulting in damage to the carrier;On the other hand,the internal temperature field can also undergo significant changes contributing to increase this risk.This study explores the gas flow uniformity in a DPF carrier and the related temperature behavior under drop-to-idle(DTI)condition by means of bench tests.It is shown that the considered silicon carbide carrier exhibits good flow uniformity,with a temperature deviation of no more than 2%with respect to the same radius measurement point at the outlet during the regeneration stage.In the DTI test,the temperature is relatively high within r/2 near the outlet end,where the maximum temperature peak occurs,and the maximum radial temperature gradient is located between r/2 and the edge.Both these quantities grow as the soot load increases,thereby making the risk of carrier burnout greater.Finally,it is shown that the soot load limit of the silicon carbide DPF can be extended to 11 g/L,which reduces the frequency of active regeneration by approximately 40%compared to a cordierite DPF.
基金the National Natural Science Foundation of China (22209091)the Natural Science Foundation of Shandong Province (ZR2020QB057)+1 种基金the Key Program of National Natural Science Foundation of China (22133006)the Yankuang Group 2019 Science and Technology Program (YKKJ2019AJ05JG-R60)。
文摘It is a challenge to coordinate carrier-kinetics performance and the redox capacity of photogenerated charges synchronously at the atomic level for boosting photocatalytic activity.Herein,the atomic Ni was introduced into the lattice of hexagonal ZnIn_(2)S_(4) nanosheets(Ni/ZnIn_(2)S_(4))via directionalsubstituting Zn atom with the facile hydrothermal method.The electronic structure calculations indicate that the introduction of Ni atom effectively extracts more electrons and acts as active site for subsequent reduction reaction.Besides the optimized light absorption range,the elevation of Efand ECBendows Ni/ZnIn_(2)S_(4) photocatalyst with the increased electron concentration and the enhanced reduction ability for surface reaction.Moreover,ultrafast transient absorption spectroscopy,as well as a series of electrochemical tests,demonstrates that Ni/ZnIn_(2)S_(4) possesses 2.15 times longer lifetime of the excited charge carriers and an order of magnitude increase for carrier mobility and separation efficiency compared with pristine ZnIn_(2)S_(4).These efficient kinetics performances of charge carriers and enhanced redox capacity synergistically boost photocatalytic activity,in which a 3-times higher conversion efficiency of nitrobenzene reduction was achieved upon Ni/ZnIn_(2)S_(4).Our study not only provides in-depth insights into the effect of atomic directional-substitution on the kinetic behavior of photogenerated charges,but also opens an avenue to the synchronous optimization of redox capacity and carrier-kinetics performance for efficient solar energy conversion.
文摘Chemical looping combustion has the potential to be an efficient and low-cost technology capable of contributing to the reduction of the atmospheric concentration of CO_(2) in order to reach the 1.5/2°C goal and mitigate climate change.In this process,a metal oxide is used as oxygen carrier in a dual fluidized bed to generate clean CO_(2) via combustion of biomass.Most commonly,natural ores or synthetic materials are used as oxygen carrier whereas both must meet special requirements for the conversion of solid fuels.Synthetic oxygen carriers are characterized by higher reactivity at the expense of higher costs versus the lower-cost natural ores.To determine the viability of both possibilities,a techno-economic comparison of a synthetic material based on manganese,iron,and copper to the natural ore ilmenite was conducted.The synthetic oxygen carrier was characterized and tested in a pilot plant,where high combustion efficiencies up to 98.4%and carbon capture rates up to 98.5%were reached.The techno-economic assessment resulted in CO_(2) capture costs of 75 and 40€/tCO_(2) for the synthetic and natural ore route respectively,whereas a sensitivity analysis showed the high impact of production costs and attrition rates of the synthetic material.The synthetic oxygen carrier could break even with the natural ore in case of lower production costs and attrition rates,which could be reached by adapting the production process and recycling material.By comparison to state-of-the-art technologies,it is demonstrated that both routes are viable and the capture cost of CO_(2) could be reduced by implementing the chemical looping combustion technology.
基金the Medical Science Research Projects in Hebei Province,No.20221526and Natural Science Foundation,No.2022-271.
文摘BACKGROUND The precise role of mitochondrial carrier homolog 2(MTCH2)in promoting malignancy in gastric mucosal cells and its involvement in gastric cancer cell metastasis have not been fully elucidated.AIM To determine the role of MTCH2 in gastric cancer.METHODS We collected 65 samples of poorly differentiated gastric cancer tissue and adjacent tissues,constructed MTCH2-overexpressing and MTCH2-knockdown cell models,and evaluated the proliferation,migration,and invasion of human gastric epithelial cells(GES-1)and human gastric cancer cells(AGS)cells.The mito-chondrial membrane potential(MMP),mitochondrial permeability transformation pore(mPTP)and ATP fluorescence probe were used to detect mitochondrial function.Mitochondrial function and ATP synthase protein levels were detected via Western blotting.RESULTS The expression of MTCH2 and ATP2A2 in gastric cancer tissues was significantly greater than that in adjacent tissues.Overexpression of MTCH2 promoted colony formation,invasion,migration,MMP expression and ATP production in GES-1 and AGS cells while upregulating ATP2A2 expression and inhibiting cell apoptosis;knockdown of MTCH2 had the opposite effect,promoting overactivation of the mPTP and promoting apoptosis.CONCLUSION MTCH2 can increase the malignant phenotype of GES-1 cells and promote the proliferation,invasion,and migration of gastric cancer cells by regulating mitochondrial function,providing a basis for targeted therapy for gastric cancer cells.
基金supported in part by the National Natural Science Foundation of China under Grant U23A20278in part by the National Natural Science Foundation of China under Grant 62171151in part by the Fundamental Research Funds for the Central Universities under Grant HIT.OCEF.2021012。
文摘The hybrid carrier(HC)system rooted in the carrier fusion concept is gradually garnering attention.In this paper,we study the extended hybrid carrier(EHC)multiple access scheme to ensure reliable wireless communication.By employing the EHC modulation,a power layered multiplexing framework is realized,which exhibits enhanced interference suppression capability owing to the more uniform energy distribution design.The implementation method and advantage mechanism are explicated respectively for the uplink and downlink,and the performance analysis under varying channel conditions is provided.In addition,considering the connectivity demand,we explore the non-orthogonal multiple access(NOMA)method of the EHC system and develop the EHC sparse code multiple access scheme.The proposed scheme melds the energy spread superiority of EHC with the access capacity of NOMA,facilitating superior support for massive connectivity in high mobility environments.Simulation results have verified the feasibility and advantages of the proposed scheme.Compared with existing HC multiple access schemes,the proposed scheme exhibits robust bit error rate performance and can better guarantee multiple access performance in complex scenarios of nextgeneration communications.
基金supported by the Major National Scientific Research Projects (2015CB932103)
文摘A pH-responsive conjugate based 10-hydroxycamptothecin-thiosemicarbazide-polyethene glycol 2000 (10-HCPT-hydro-PEG) nano-micelles were prepared in our previous study. In the present study, ultra-performance liquid chromatography (UPLC-MS) method is developed to investigate its pharmacokinetics and biodistribution in tumor bearing mice. The results demonstrated that the conjugate circulated for a much longer time in the blood circulation system than commercial 10-HCPT injection, and bioavailability was significantly improved compared with 10-HCPT. In vivo biodistribution study showed that the conjugate could enhance the targeting and residence time in tumor site.
基金the support of the National Natural Science Foundation of China(22005276)。
文摘Converting polyethylene terephthalate(PET)wastes to its monomer and valuable chemicals via ecofriendly chemical method is still a challenge task.Previously,phase transfer catalysts used for alkaline hydrolysis were soluble in reaction media and hardly separated after reaction.Here,we reported several pH-responsive catalysts combined alkyl quaternary ammonium units with heteropolyacid anion for achieving stepwise product/catalyst separation and catalyst recycling.The properties of homogeneous/heterogeneous transfer behavior allow catalyst to be easily separated from reaction media by adjusting of pH value.Among them,[C_(16)H_(33)N(CH_(3))_(3)]_(3)PW_(12)O_(40)(abbreviated as[CTA]_(3)PW)exhibits the highest activity and the most suitable pH responsive values.Such a pH triggered switchable catalytic system not only shows good performance for depolymerization of pure PET,but also some real PET wastes such as coloured trays and PE/PET complex films could be completely degraded into terephthalic acid.Additionally,the reaction kinetics and activation energy of PET alkaline hydrolysis also studied with and without pH-responsive[CTA]_(3)PW.
基金partially supported by the National Natural Science Foundation of China(51802209,22077093,51761145041,51525203)the National Research Programs from Ministry of Science and Technology(MOST)of China(2016YFA0201200)+3 种基金the Natural Science Foundation of Jiangsu Province(BK20180848)the Jiangsu Social Development Project(BE2019658)Collaborative Innovation Center of Suzhou Nano Science and Technologythe 111 Program from the Ministry of Education of China.
文摘Due to the negative roles of tumor microenvironment(TME)in compromising therapeutic responses of various cancer therapies,it is expected that modulation of TME may be able to enhance the therapeutic responses during cancer treatment.Herein,we develop a concise strategy to prepare pH-responsive nanoparticles via the CaCO3-assisted double emulsion method,thereby enabling effective co-encapsulation of both doxorubicin(DOX),an immunogenic cell death(ICD)inducer,and alkylated NLG919(aNLG919),an inhibitor of indoleamine 2,3-dioxygenase 1(IDO1).The obtained DOX/aNLG919-loaded CaCO3 nanoparticles(DNCaNPs)are able to cause effective ICD of cancer cells and at the same time restrict the production of immunosuppressive kynurenine by inhibiting IDO1.Upon intravenous injection,such DNCaNPs show efficient tumor accumulation,improved tumor penetration of therapeutics and neutralization of acidic TME.As a result,those DNCaNPs can elicit effective anti-tumor immune responses featured in increased density of tumor-infiltrating CD8+cytotoxic T cells as well as depletion of immunosuppressive regulatory T cells(Tregs),thus effectively suppressing the growth of subcutaneous CT26 and orthotopic 4T1 tumors on the Balb/c mice through combined chemotherapy&immunotherapy.This study presents a compendious strategy for construction of pH-responsive nanoparticles,endowing significantly enhanced chemo-immunotherapy of cancer by overcoming the immunosuppressive TME.
基金supported by the National Natural Science Foundation of China(No.52090030)the China Postdoctoral Science Foundation(2022T150558,2020M681819)+1 种基金the Fundamental Research Funds for the Central Universities(No.2021FZZX001-17)the Postdoctoral Research Program of Zhejiang Province(ZJ2021145).
文摘Bulk graphene nanofilms feature fast electronic and phonon transport in combination with strong light-matter interaction and thus have great potential for versatile applications,spanning from photonic,electronic,and optoelectronic devices to charge-stripping and electromagnetic shielding,etc.However,large-area flexible close-stacked graphene nanofilms with a wide thickness range have yet to be reported.Here,we report a polyacrylonitrile-assisted’substrate replacement’strategy to fabricate large-area free-standing graphene oxide/polyacrylonitrile nanofilms(lateral size~20 cm).Linear polyacrylonitrile chains-derived nanochannels promote the escape of gases and enable macro-assembled graphene nanofilms(nMAGs)of 50-600 nm thickness following heat treatment at 3,000℃.The uniform nMAGs exhibit 802-1,540 cm^(2)V-1s-1carrier mobility,4.3-4.7 ps carrier lifetime,and>1,581 W m^(-1)K^(-1)thermal conductivity(n MAG-assembled 10μm-thick films,mMAGs).nMAGs are highly flexible and show no structure damage even after 1.0×10^(5)cycles of folding-unfolding.Furthermore,n MAGs broaden the detection region of graphene/silicon heterojunction from near-infrared to mid-infrared and demonstrate higher absolute electromagnetic interference(EMI)shielding effectiveness than state-of-the-art EMI materials of the same thickness.These results are expected to lead to the broad applications of such bulk nanofilms,especially as micro/nanoelectronic and optoelectronic platforms.
基金The authors greatly acknowledge the financial support from the National Natural Science Foundation of China(No.51863007).
文摘Preparation of polymer microspheres from naturally occurring resource is a challenge.Here,a rosin-based polyol(RAG)was used to prepare polyurethane resin(RPU)firstly,and then act as both self-assembled precursor and emulsifier,rosin based polyurethane microspheres(RPUMs)were prepared.In the process of self-emulsification,the RPU formed vesicles by self-assembly.The outer shell of the vesicle consisted of hydrophilic segments,while the inner shell contained the hydrophobic phase.After cross-linking the RPU and removal of the solvent in the core,the porous-hollow microspheres with pH-sensitive were obtained.The microspheres were characterized by optical microscope(OM),scanning electron microscopy(SEM)and transmission electron microscope(TEM).The effect of type and amount of the hydrophilic chain extender,and solvent on the morphology,particle size and distribution,and buffer volume of the microspheres were determined.The best conditions for synthetic RPUMs were as follows:n_(NCO)/n_(OH)=1,n_(RAG):n_(1-(2-hydroxyethyl)piperazine)=4:6,with azodiisobutyronitrile level of 1.0 wt.%,based on reactive monomers,mixing speed of both emulsification and polymerization at 400 r·min-1,the RPUMs synthesized had porous-hollow structure with a buffer volume of 1.6 mL.
基金the National Key Research and Development Program of China (2021YFA1501302)the National Natural Science Foundation of China (22122808, U20B6002)+1 种基金the Haihe Laboratory of Sustainable Chemical Transformations and the Program of Introducing Talents of Discipline to Universities (BP0618007) for financial supportsupported by the XPLORER PRIZE by Tencent Foundation
文摘The oxygen distribution and evolution within the oxygen carrier exert significant influence on chemical looping processes.This paper describes the influence of oxygen bulk diffusion within FeVO4 oxygen carrier pellets on the chemical looping oxidative propane dehydrogenation(CL-ODH).During CL-ODH,the oxygen concentration at the pellet surface initially decreased and then maintained stable before the final decrease.At the stage with the stable surface oxygen concentration,the reaction showed a stable C3H6 formation rate and high C3H6 selectivity.Therefore,based on Fick’s second law,the oxygen distribution and evolution in the oxygen carrier at this stage were further analyzed.It was found that main reactions of selective oxidation and over-oxidation were controlled by the oxygen bulk diffusion.C3H8 conversion rate kept decreasing during this stage due to the decrease of the oxygen flux caused by the decline of oxygen gradient within the oxygen carrier,while C3H6 selectivity increased due to the decrease of overoxidation.In addition,reaction rates could increase with the propane partial pressure due to the increase of the oxygen gradient within the oxygen carrier until the bulk transfer reached its limit at higher propane partial pressure.This study provides fundamental insights for the diffusion-controlled chemical looping reactions.
基金supported by grants from projects of Interdisciplinary Research Foundation of HIT,the National Natural Science Foundation of China(No.82071980)the International Cooperation and Exchanges NSFC-PSF(No.31961143003)+1 种基金the State Key Program of National Natural Science of China(No.81930047)the National Project for Research and Development of Major Scientifc Instruments(No.81727803).
文摘Targeted photodynamic therapy(TPDT)based on the photosensitizers responsive for tumor micr oenvironment is promising because of the better anti-tumor effect and less phototoxicity against normal tissue than the traditional PDT.Nanoparticle based stimuli responsive photo-sensitizers have been widely explored for TPDT.Based on the acidic microenvironments in solid tumors,an ultrasmall pH-responsive silicon phthalocyanine nanomicelle(PSN)(smaller than 10 nm)was designed for selective PDT of tumor.PSN had high drug loading efficacy(more than 28%)and exhibited morphological transitions,enhanced fuorescence and improved singlet∞x-ygen yield under acidic environments.PSN was renal dlearable and could rapidly accumulate and be retained at tumor sites,achieving a tumor-inhibiting ffect better than phthalocyanine micelle without pH response.Tumors of mice treated with PSN for PDT were completely ablated without recurrence.Thus,we have developed a phthalocyanine-based pH responsive micelle with excellent tumor targeting ability,which is expected to realize the selective PDT of tumor.
基金the National Natural Science Foundation of China(No.81872813,22108313,82273880)Natural Science Foundation of Jiangsu Province(No.BK 20200573,BK 20200576)+1 种基金Fundamental Research Funds for the Central Universities(No 2632022ZD16)the Scientific Research Fund of Hunan Provincial Education Department(No.22B0820).
文摘Amorphous solid dispersion(ASD)is one of the most effective approaches for delivering poorly soluble drugs.In ASDs,polymeric materials serve as the carriers in which the drugs are dispersed at the molecular level.To prepare the solid dispersions,there are many polymers with various physicochemical and thermochemical characteristics available for use in ASD formulations.Polymer selection is of great importance because it influences the stability,solubility and dissolution rates,manufacturing process,and bioavailability of the ASD.This review article provides a comprehensive overview of ASDs from the perspectives of physicochemical characteristics of polymers,formulation designs and preparation methods.Furthermore,considerations of safety and regulatory requirements along with the studies recommended for characterizing and evaluating polymeric carriers are briefly discussed.
基金financially supported by the Support Plan for Overseas Students to Return to China for Entrepreneurship and Innovation(cx2020003)the Fundamental Research Funds for the Central Universities(2020CDJ-LHZZ-074)the Natural Science Foundation of Chongqing(cstc2020jcyj-msxm X0629)。
文摘The defects from electron transport layer,perovskite layer and their interface would result in carrier nonradiative recombination losses.Poor buried interfacial contact is detrimental to charge extraction and device stability.Here,we report a bottom-up holistic carrier management strategy induced synergistically by multiple chemical bonds to minimize bulk and interfacial energy losses for high-performance perovskite photovoltaics.4-trifluoromethyl-benzamidine hydrochloride(TBHCl)containing–CF_(3),amidine cation and Cl^(-)is in advance incorporated into SnO_(2)colloid solution to realize bottom-up modification.The synergistic effect of multiple functional groups and multiple-bond-induced chemical interaction are revealed theoretically and experimentally.F and Cl^(-)can passivate oxygen vacancy and/or undercoordinated Sn^(4+)defects by coordinating with Sn^(4+).The F can suppress cation migration and modulate crystallization via hydrogen bond with FA^(+),and can passivate lead defects by coordinating with Pb^(2+).The–NH_(2)–C=NH^(+)_(2)and Cl^(-)can passivate cation and anion vacancy defects through ionic bonds with perovskites,respectively.Through TBHCl modification,the suppression of agglomeration of SnO_(2)nanoparticles,bulk and interfacial defect passivation,and release of tensile strains of perovskite films are demonstrated,which resulted in a PCE enhancement from 21.28%to 23.40%and improved stability.With post-treatment,the efficiency is further improved to 23.63%.