Superhydrophobic surface(SHS) has been well developed, as SHS renders the property of minimizing the water/solid contact interface. Water droplets deposited onto SHS with contact angles exceeding 150°, allow them...Superhydrophobic surface(SHS) has been well developed, as SHS renders the property of minimizing the water/solid contact interface. Water droplets deposited onto SHS with contact angles exceeding 150°, allow them to retain spherical shapes, and the low adhesion of SHS facilitates easy droplet collection when tilting the substrate. These characteristics make SHS suitable for a wide range of applications. One particularly promising application is the fabrication of microsphere and supraparticle materials. SHS offers a distinct advantage as a universal platform capable of providing customized services for a variety of microspheres and supraparticles. In this review, an overview of the strategies for fabricating microspheres and supraparticles with the aid of SHS, including cross-linking process, polymer melting,and droplet template evaporation methods, is first presented. Then, the applications of microspheres and supraparticles formed onto SHS are discussed in detail, for example, fabricating photonic devices with controllable structures and tunable structural colors, acting as catalysts with emerging or synergetic properties, being integrated into the biomedical field to construct the devices with different medicinal purposes, being utilized for inducing protein crystallization and detecting trace amounts of analytes. Finally,the perspective on future developments involved with this research field is given, along with some obstacles and opportunities.展开更多
The optical diffraction effect imposes a radical obstacle preventing conventional optical microscopes from achieving an imaging resolution beyond the Abbe diffraction limit and thereby restricting their usage in a mul...The optical diffraction effect imposes a radical obstacle preventing conventional optical microscopes from achieving an imaging resolution beyond the Abbe diffraction limit and thereby restricting their usage in a multitude of nanoscale applications.Over the past decade,the optical microsphere nanoimaging technique has been demonstrated to be a cost-effective solution for overcoming the diffraction limit and has achieved an imaging resolution of up to about k6k8 in a real-time and label-free manner,making it highly competitive among numerous super-resolution imaging technologies.In this review,we summarize the underlying nano-imaging mechanisms of the microsphere nanoscope and key advancements aimed at imaging performance enhancement:first,to change the working environment or modify the peripheral hardware of a single microsphere nanoscope at the system level;second,to compose the microsphere compound lens;and third,to engineer the geometry or ingredients of microspheres.We also analyze challenges yet to be overcome in optical microsphere nano-imaging,followed by an outlook of this technique.展开更多
3D hierarchical flowerlike WS_(2) microspheres were synthesized through a facile one-pot hydrothermal route.The as-synthesized samples were characterized by powder X-ray powder diffraction (XRD),energy-dispersive spec...3D hierarchical flowerlike WS_(2) microspheres were synthesized through a facile one-pot hydrothermal route.The as-synthesized samples were characterized by powder X-ray powder diffraction (XRD),energy-dispersive spectroscopy (EDS),scanning electron microscopy (SEM) and Raman.SEM images of the samples reveal that the hierarchical flowerlike WS_(2) microspheres with diameters of about 3-5μm are composed of a number of curled nanosheets.Electrochemical tests such as charge/discharge,cyclic voltammetry,cycle life and rate performance were carried out on the WS_(2) sample.As an anode material for lithium-ion batteries,hierarchical flowerlike WS_(2) microspheres show excellent electrochemical performance.At a current density of100 mA·g^(-1),a high specific capacity of 647.8 mA·h·g^(-1) was achieved after 120 discharge/charge cycles.The excellent electrochemical performance of WS_(2) as an anode material for lithium-ion batteries can be attributed to its special 3D hierarchical structure.展开更多
Polymer microspheres(PMs),such as polyacrylamide,have been widely applied for enhanced oil recovery(EOR),yet with environmental concerns.Here,we report a microfluid displacement technology containing a bio-based eco-f...Polymer microspheres(PMs),such as polyacrylamide,have been widely applied for enhanced oil recovery(EOR),yet with environmental concerns.Here,we report a microfluid displacement technology containing a bio-based eco-friendly material,i.e.,calcium alginate(CaAlg)microspheres for EOR.Two dominant mechanisms responsible for EOR over Ca Alg fluid have been verified,including the microscopic oil displacement efficacy augmented by regulating capillary force(determined by the joint action of interfacial tension and wettability between different phases)and macroscopic sweep volume increment through profile control and mobility ratio reduction.This comprehensive effectiveness can be further impacted when the CaAlg microsphere is embellished ulteriorly by using appropriate amount of sodium dodecyl sulfonate(SDS).The core flooding and nuclear magnetic resonance(NMR)tests demonstrate that CaAlg-SDS microsphere can balance the interphase property regulation(wettability alteration and IFT reduction)and rheology properties,enabling simultaneous profile control and oil displacement.Excessive introduction of SDS will have a negative impact on rheological properties,which is not favored for EOR.Our results show that the involvement of 4-m M SDS will provide the best behavior,with an EOR rate of 34.38%.This cost-effective and environmentally-friendly bio-microspherebased microfluidic displacement technology is expected to achieve“green”oil recovery in future oilfield exploitation.展开更多
Background:In facial plastic surgery,patients with nasal deformity are often treated by rib cartilage transplantation.In recent years,cartilage tissue engineering has developed as an alternative to complex surgery for...Background:In facial plastic surgery,patients with nasal deformity are often treated by rib cartilage transplantation.In recent years,cartilage tissue engineering has developed as an alternative to complex surgery for patients with minor nasal defects via injection of nasal filler material.In this study,we prepared an injectable nasal filler material containing poly-L-l actic acid(PLLA)porous microspheres(PMs),hyaluronic acid(HA)and adipose-derived mesenchymal stem cells(ADMSCs).Methods:We seeded ADMSCs into as-prepared PLLA PMs using our newly invented centrifugation perfusion technique.Then,HA was mixed with ADMSC-i ncorporated PLLA PMs to form a hydrophilic and injectable cell delivery system(ADMSCincorporated PMH).Results:We evaluated the biocompatibility of PMH in vitro and in vivo.PMH has good injectability and provides a favorable environment for the proliferation and chondrogenic differentiation of ADMSCs.In vivo experiments,we observed that PMH has good biocompatibility and cartilage regeneration ability.Conclusion:In this study,a injectable cell delivery system was successfully constructed.We believe that PMH has potential application in cartilage tissue engineering,especially in nasal cartilage regeneration.展开更多
Broadband electromagnetic(EM)wave absorption materials play an important role in military stealth and health protection.Herein,metal–organic frameworks(MOFs)-derived magnetic-carbon CoNiM@C(M=Cu,Zn,Fe,Mn)microspheres...Broadband electromagnetic(EM)wave absorption materials play an important role in military stealth and health protection.Herein,metal–organic frameworks(MOFs)-derived magnetic-carbon CoNiM@C(M=Cu,Zn,Fe,Mn)microspheres are fabricated,which exhibit flower-like nano–microstructure with tunable EM response capacity.Based on the MOFs-derived CoNi@C microsphere,the adjacent third element is introduced into magnetic CoNi alloy to enhance EM wave absorption performance.In term of broadband absorption,the order of efficient absorption bandwidth(EAB)value is Mn>Fe=Zn>Cu in the CoNiM@C microspheres.Therefore,MOFs-derived flower-like CoNiMn@C microspheres hold outstanding broadband absorption and the EAB can reach up to 5.8 GHz(covering 12.2–18 GHz at 2.0 mm thickness).Besides,off-axis electron holography and computational simulations are applied to elucidate the inherent dielectric dissipation and magnetic loss.Rich heterointerfaces in CoNiMn@C promote the aggregation of the negative/positive charges at the contacting region,forming interfacial polarization.The graphitized carbon layer catalyzed by the magnetic CoNiMn core offered the electron mobility path,boosting the conductive loss.Equally importantly,magnetic coupling is observed in the CoNiMn@C to strengthen the magnetic responding behaviors.This study provides a new guide to build broadband EM absorption by regulating the ternary magnetic alloy.展开更多
CO_(2) flooding is a vital development method for enhanced oil recovery in low-permeability reservoirs,However,micro-fractures are developed in low-permeability reservoirs,which are essential oil flow channels but can...CO_(2) flooding is a vital development method for enhanced oil recovery in low-permeability reservoirs,However,micro-fractures are developed in low-permeability reservoirs,which are essential oil flow channels but can also cause severe CO_(2) gas channeling problems.Therefore,anti-gas channeling is a necessary measure to improve the effect of CO_(2) flooding.The kind of anti-gas channeling refers to the plugging of fractures in the deep formation to prevent CO_(2) gas channeling,which is different from the wellbore leakage.Polymer microspheres have the characteristics of controllable deep plugging,which can achieve the profile control of low-permeability fractured reservoirs.In acidic environments with supercritical CO_(2),traditional polymer microspheres have poor expandability and plugging properties.Based on previous work,a systematic evaluation of the expansion performance,dispersion rheological properties,stability,deep migration,anti-CO_(2) channeling and enhanced oil recovery ability of a novel acid-resistant polymer microsphere(DCNPM-A)was carried out under CQ oilifield conditions(salinity of85,000 mg/L,80℃,pH=3).The results show that the DCNPM-A microsphere had a better expansion performance than the traditional microsphere,with a swelling rate of 13.5.The microsphere dispersion with a concentration of 0.1%-0.5%had the advantages of low viscosity,high dispersion and good injectability in the low permeability fractured core.In the acidic environment of supercritical CO_(2),DCNPM-A microspheres showed excellent stability and could maintain strength for over 60 d with less loss.In core experiments,DCNPM-A microspheres exhibited delayed swelling characteristics and could effectively plug deep formations.With a plugging rate of 95%,the subsequent enhanced oil recovery of CO_(2) flooding could reach 21.03%.The experimental results can provide a theoretical basis for anti-CO_(2)channeling and enhanced oil recovery in low-permeability fractured reservoirs.展开更多
[Objectives]This study was conducted to investigate the effects of slow-release nitrogen fertilizer on dry matter accumulation and translocation of summer maize.[Methods]With Zhoudan 9 as the test variety,six differen...[Objectives]This study was conducted to investigate the effects of slow-release nitrogen fertilizer on dry matter accumulation and translocation of summer maize.[Methods]With Zhoudan 9 as the test variety,six different treatment were set up:blank control(CK1),slow-release urea 75 kg/hm^(2)(C1),slow-release urea 150 kg/hm^(2)(C2),slow-release urea 225 kg/hm^(2)(C3),slow-release urea 300 kg/hm^(2)(C4)and ordinary urea 300 kg/hm^(2)(CK2),to study the change law of dry matter accumulation and translocation in summer maize.[Results]Treatment slow-release urea 225 kg/hm^(2)(C4)showed summer maize yield,dry matter translocation between organs,grain contribution rate and proportion of grain dry matter in the full ripe stage higher than other treatments.Considering the weight loss and cost factors,slow-release urea 225 kg/hm^(2)(C3)could be recommended as the fertilizing amount for summer maize.[Conclusions]This study provides theoretical reference for rational selection of fertilizers for reducing fertilizer application and increasing fertilizer efficiency,and for production of summer maize in Shajiang black soil region.展开更多
BACKGROUND Transhepatic arterial chemoembolization(TACE),as a local treatment,has been widely used in the treatment of unresectable liver cancer.The introduction of drug carrier microspheres has brought new hope for t...BACKGROUND Transhepatic arterial chemoembolization(TACE),as a local treatment,has been widely used in the treatment of unresectable liver cancer.The introduction of drug carrier microspheres has brought new hope for the therapeutic effect of TACE.Microspheres can realize the slow release and directional delivery of drugs,reduce systemic toxicity and improve local curative effect.AIM To compare the effectiveness of traditional transcatheter arterial chemoembolization against microsphere-assisted transcatheter arterial chemoembolization in the treatment of hepatocellular carcinoma that is incurable.METHODS We searched the PubMed,Embase,Cochrane Library,and CNKI databases for clinical trials of drug-luting beads TACE(DEB-TACE)vs conventional TACE(cTACE)for the treatment of unresectable liver cancer.We screened references based on inclusion and exclusion criteria and then selected valid data for meta-analysis using RevMan 53 software.The complete response(CR)rate,partial response(PR)rate,postoperative stable disease(SD)rate,and 6-month and 12-month survival rates were compared.RESULTS A total of 12 articles were included,including 1177 patients,519 of whom received DEB-TACE and 658 of whom received cTACE.The CR rate in the DEB-TACE group was much greater than that in the cTACE group[relative risk(RR)=1.42,95%CI:1.18-1.72,P=0.0002].The 12-month survival rate significantly increased(RR=1.09;95%CI:1.01-1.17,P=0.03);the PR rate(RR=1.13;95%CI:0.97-1.30,P=0.12);the SD rate(RR=0.82;95%CI:0.64-1.05,P=0.12);and the 6-month survival rate(RR=1.05;95%CI:1.00-1.10,P=0.07).There was no significant difference(P<0.05).CONCLUSION Compared with those of iodized oil TACE,the drug-loaded microspheres tended to have therapeutic advantages.展开更多
[Objectives] This study was conducted to verify the field application effect of slow-release nitrogen fertilizer on summer maize in Shajiang black soil area by simultaneous sowing and fertilization, and explore the ap...[Objectives] This study was conducted to verify the field application effect of slow-release nitrogen fertilizer on summer maize in Shajiang black soil area by simultaneous sowing and fertilization, and explore the application scope and nitrogen metabolism mechanism, so as to lay a foundation for fertilizer reduction and efficiency improvement. [Methods] With maize variety Beiqing 340 and sulfur-coated urea as experimental materials, five nitrogen application levels were set, namely, control (C0), slow-release nitrogen 70 kg/hm^(2) (C70), slow-release nitrogen 140 kg/hm^(2) (C140), slow-release nitrogen 210 kg/hm^(2) (C210) and slow-release nitrogen 280 kg/hm^(2) (C280). The phosphorus and potassium fertilizers were all in accordance with the unified standard. [Results] With the application rate of slow-release nitrogen increasing, the nitrogen accumulation in organs increased first and then decreased after tasseling stage of maize. In order to reduce the fertilizing amount and increase efficiency, 210 kg/hm^(2) of slow-release nitrogen fertilizer was the best fertilizing amount for summer maize in Shajiang black soil area. [Conclusions] This study provides reference for fertilizer reduction, efficiency improvement and sustainable development of summer maize in Shajiang black soil area.展开更多
Metal(aluminum and boron)based energetic materials have been wildly applied in various fields including aerospace,explosives and micro-devices due to their high energy density.Unfortunately,the low combustion efficien...Metal(aluminum and boron)based energetic materials have been wildly applied in various fields including aerospace,explosives and micro-devices due to their high energy density.Unfortunately,the low combustion efficiency and reactivity of metal fuels,especially boron(B),severely limit their practical applications.Herein,multi-component 3D microspheres of HMX/B/Al/PTFE(HBA)have been designed and successfully prepared by emulsion and solvent evaporation method to achieve superior energy and combustion reactivity.The reactivity and energy output of HBA are systematically measured by ignitionburning test,constant-volume explosion vessel system and bomb calorimetry.Due to the increased interfacial contact and reaction area,HBA shows higher flame propagation rate,faster pressurization rate and larger combustion heat of 29.95 cm/s,1077 kPa/s,and 6164.43 J/g,which is 1.5 times,3.5 times,and 1.03 times of the physical mixed counterpart(HBA-P).Meanwhile,HBA also shows enhanced energy output and reactivity than 3D microspheres of HMX/B/PTFE(HB)resulting from the high reactivity of Al.The reaction mechanism of 3D microspheres is comprehensively investigated through combustion emission spectral and thermal analysis(TG-DSC-MS).The superior reactivity and energy of HBA originate from the surface etching of fluorine to the inert shell(Al_(2)O_(3) and B_(2)O_(3))and the initiation effect of Al to B.This work offers a promising approach to design and prepare high-performance energetic materials for the practical applications.展开更多
[Objectives]To optimize the formulation and preparation of oregano oil microspheres by Box-Behnken response surface methodology.[Methods]Chitosan was used as the carrier material to prepare oregano oil microspheres by...[Objectives]To optimize the formulation and preparation of oregano oil microspheres by Box-Behnken response surface methodology.[Methods]Chitosan was used as the carrier material to prepare oregano oil microspheres by emulsion crosslinking method.The encapsulation efficiency,drug loading and ID 50 were used as the evaluation indicators,and the comprehensive score(OD)obtained by"coefficient of variation-AHP comprehensive weighting method"was used as the final evaluation indicator.The formulation design and preparation process were optimized by single factor experiment and Box-Behnken response surface methodology,and the optimal process parameters were determined.[Results]The optimal formulation and preparation process parameters of oregano oil microspheres were as follows:the ratio of oregano oil to chitosan was 2∶1,the emulsifying speed of double emulsion was 200 r/min,the amount of emulsifier in the colostrum was 4%,and the volume of curing agent was 1.0 mL.The average encapsulation efficiency was 45.33%±1.32%,the average drug loading was 30.59%±2.45%,and the median diameter(ID 50)was 52.596μm±0.023%.[Conclusions]The encapsulation efficiency,drug loading and ID 50 of oregano oil chitosan microspheres prepared by emulsion crosslinking method met the requirements.The drug-loaded microsphere not only can be used as a preparation finished product for direct application,but also be used as a product intermediate to lay a foundation for the research and development of subsequent dosage forms.展开更多
A wound care system consisting of ciprofloxacin-loaded gelatin microspheres impregnated in a macroporous collagen scaffold was created to effectively control wound infection and regenerate soft tissue at the wound sit...A wound care system consisting of ciprofloxacin-loaded gelatin microspheres impregnated in a macroporous collagen scaffold was created to effectively control wound infection and regenerate soft tissue at the wound site.Histological and biochemical alterations were observed in infected wounds treated with these scaffolds in Albino Wistar rats.Furthermore,the study examined the immediate and prolonged release of ciprofloxacin from the scaffolds,as well as their function in eliminating bacterial infections and expediting the process of skin healing and regeneration.The developed technique was followed in the streamlined process of creating these collagen scaffolds.Compared to untreated wounds,the group receiving scaffold treatment experienced a faster rate of wound closure.It was noted that the rate of infections was considerably reduced and that full soft tissue regeneration occurred within 12 days.The development of well-deposited collagen bundles in the treated groups was demonstrated by H&E staining,which verified the flawless regeneration of the dermis and epidermis.The antimicrobial agent-loaded gelatin microspheres impregnated into the porous collagen scaffold demonstrated remarkable soft tissue regeneration and efficient infection control at the wound site.展开更多
Microspheres are a new type of drug carrier with great potential for development and application.Natural polymers have good biocompatibility,biodegradability,and are easily dispersed in living organisms,making them su...Microspheres are a new type of drug carrier with great potential for development and application.Natural polymers have good biocompatibility,biodegradability,and are easily dispersed in living organisms,making them suitable for preparing microspheres.Inorganic materials(mainly inorganic minerals)have excellent mechanical properties and are inexpensive and easy to obtain.Through the coupling and hybridization of natural polymers and inorganic materials,they can complement each other's advantages and synergistically enhance efficiency,resulting in many excellent physical and chemical properties.Inorganic materials/natural polymer composite microspheres can be prepared by modifying natural polymers with inorganic materials through various methods such as emulsification crosslinking,solution mixing,in-situ synthesis,extrusion,etc.The application of inorganic materials/natural polymer composite microspheres in drug delivery systems has significant sustained-release effects,is safe and non-toxic,and the cost of carrier materials is relatively low,which has certain significance for the development of new drug carriers.This article reviews the recent research on the preparation,drug loading and release properties of inorganic material/natural polymer composite microspheres,analyzes the advantages and disadvantages of commonly used preparation methods,and looks forward to the development direction of composite microspheres.展开更多
Functional porous microspheres used for the slow release carrier of actives in cosmetics or pharmaceuticals were prepared by modified suspension polymerization of styrene (ST) with divinylbenzene (DVB) in the pres...Functional porous microspheres used for the slow release carrier of actives in cosmetics or pharmaceuticals were prepared by modified suspension polymerization of styrene (ST) with divinylbenzene (DVB) in the presence of toluene, cyclohexanol and heptane as porogenic diluents. The use of ultrasonic dispersion decreases the beads' size and improves the uniformity. The effects of the porogen mixture, DVB content and solvent extraction on the surface performance of the synthesized beads were studied. The microspheres were characterized by scanning electron microscopy (SEM) and BET surface area determination. It was found that a great proportion of the non-solvating porogen increases the pore diameter and the specific surface area. High DVB concentration also results in the great specific surface area and porosity. When the ratio of toluene/cyclohexanol is 1:2, DVB content is at the range of 40%-60% and methylene chloride was used as extractant, the beads with good spherical shape and pore size were obtained. The prepared porous microspheres were applied as active carriers and showed satisfactory slow release effect. Over 10h constantly sustained release was observed in vitro releasing test for hydroquinone-loaded microspheres. Great surface area promoted high concentration of released hydroquinone.展开更多
Functional porous microspheres used for the slow release carrier of actives in cosmetics or pharmaceu- ticals were prepared by modified suspension polymerization of styrene (ST) with divinylbenzene (DVB) in the presen...Functional porous microspheres used for the slow release carrier of actives in cosmetics or pharmaceu- ticals were prepared by modified suspension polymerization of styrene (ST) with divinylbenzene (DVB) in the presence of toluene, cyclohexanol and heptane as porogenic diluents. The use of ultrasonic dispersion decreases the beads’ size and improves the uniformity. The effects of the porogen mixture, DVB content and solvent extraction on the surface performance of the synthesized beads were studied. The microspheres were characterized by scanning electron microscopy (SEM) and BET surface area determination. It was found that a great proportion of the non-solvating porogen increases the pore diameter and the specific surface area. High DVB concentration also re- sults in the great specific surface area and porosity. When the ratio of toluene/cyclohexanol is 1:2, DVB content is at the range of 40%—60% and methylene chloride was used as extractant, the beads with good spherical shape and pore size were obtained. The prepared porous microspheres were applied as active carriers and showed satisfactory slow release effect. Over 10h constantly sustained release was observed in vitro releasing test for hydro- quinone-loaded microspheres. Great surface area promoted high concentration of released hydroquinone.展开更多
Drug-loaded microspheres are significant for the development of modern pharmaceutical products. It is well known that the taken of aspirin for long-term increases the risk of serious gastrointestinal complications, th...Drug-loaded microspheres are significant for the development of modern pharmaceutical products. It is well known that the taken of aspirin for long-term increases the risk of serious gastrointestinal complications, therefore a controllable delivery of aspirin is of importance to lighten those side effects. In this work, poly(lactic acid)(PLA) was chosen as the carrier to prepare PLA-aspirin microspheres by using the traditional and the improved solvent evaporation methods. It was found that no matter which experimental condition was, the encapsulation efficiency of aspirin was higher by using the improved method than that of the traditional method. Specifically, when the concentration of polyvinyl alcohol = 1%(mass),the polymer concentration = 1:20, the oil/water rate = 1:2.5, PLA-aspirin microspheres were obtained via the improved method with a high yield of 82.83%(mass) and an encapsulation efficiency of 44.09%. PLAaspirin microspheres were then prepared continuously using the improved method, which further enhanced the encapsulation efficiency to 54.56%. Approximate 85% aspirin released from microspheres within 7 days. Obvious degradation which was represented by reduction on hardness was observed by soaking microspheres in PBS for 60 days. This work is of interest because it provides a continuous route to prepare PLA-aspirin microspheres continuously with a high drug encapsulation efficiency.展开更多
Multi-layer 2D material assemblies provide a great number of interfaces beneficial for electromagnetic wave absorption.However,avoiding agglomeration and achieving layer-by-layer ordered intercalation remain chal-leng...Multi-layer 2D material assemblies provide a great number of interfaces beneficial for electromagnetic wave absorption.However,avoiding agglomeration and achieving layer-by-layer ordered intercalation remain chal-lenging.Here,3D reduced graphene oxide(rGO)/MXene/TiO_(2)/Fe_(2)C lightweight porous microspheres with periodical intercalated structures and pronounced inter-facial effects were constructed by spray-freeze-drying and microwave irradiation based on the Maxwell–Wagner effect.Such approach reinforced interfacial effects via defects introduction,porous skeleton,multi-layer assembly and multi-compo-nent system,leading to synergistic loss mechanisms.The abundant 2D/2D/0D/0D intercalated heterojunctions in the microspheres provide a high density of polari-zation charges while generating abundant polarization sites,resulting in boosted interfacial polarization,which is verified by CST Microwave Studio simulations.By precisely tuning the 2D nanosheets intercalation in the heterostructures,both the polarization loss and impedance matching improve significantly.At a low filler loading of 5 wt%,the polarization loss rate exceeds 70%,and a minimum reflection loss(RLmin)of-67.4 dB can be achieved.Moreover,radar cross-section simulations further confirm the attenuation ability of the optimized porous microspheres.These results not only provide novel insights into understanding and enhancing interfacial effects,but also constitute an attractive platform for implementing heterointerface engineering based on customized 2D hierarchical architectures.展开更多
Creation of arbitrary features with high resolution is critically important in the fabrication of nano-optoelectronic devices.Here,sub-50 nm surface structuring is achieved directly on Sb2S3 thin films via microsphere...Creation of arbitrary features with high resolution is critically important in the fabrication of nano-optoelectronic devices.Here,sub-50 nm surface structuring is achieved directly on Sb2S3 thin films via microsphere femtosecond laser irradi-ation in far field.By varying laser fluence and scanning speed,nano-feature sizes can be flexibly tuned.Such small patterns are attributed to the co-effect of microsphere focusing,two-photons absorption,top threshold effect,and high-repetition-rate femtosecond laser-induced incubation effect.The minimum feature size can be reduced down to~30 nm(λ/26)by manipulating film thickness.The fitting analysis between the ablation width and depth predicts that the feature size can be down to~15 nm at the film thickness of~10 nm.A nano-grating is fabricated,which demonstrates desirable beam diffraction performance.This nano-scale resolution would be highly attractive for next-generation laser nano-lithography in far field and in ambient air.展开更多
The“battery type”inorganic electrode has been demonstrated the highly efficient sodium ion intercalation capacity for capacitive deionization.In this work,the CoMn_(2)O_(4)(CMO)microspheres with porous core-shell st...The“battery type”inorganic electrode has been demonstrated the highly efficient sodium ion intercalation capacity for capacitive deionization.In this work,the CoMn_(2)O_(4)(CMO)microspheres with porous core-shell structure are prepared via co-precipitation and followed by annealing.The effects of annealing temperatures on the morphology,pore structure,valence state,and electrochemical behavior of CMO are explored.As electrode for capacitive deionization,the salt removal capacity and current efficiency of optimized AC||CMO device reaches up to 60.7 mg g^(−1) and 97.6%,respectively,and the capacity retention rate is 74.1%after 50 cycles.Remarkably,both the in-situ X-ray diffraction and ex-situ X-ray diffraction analysis features that the intercalation/de-intercalation of sodium ions are governed by(103)and(221)crystal planes of CMO.Accordingly,the density functional theory calculations realize that the adsorption energies of Na+onto(103)and(221)crystal planes are higher than that of any other crystal planes,manifesting the priorities in adsorption of sodium atoms.Furthermore,the X-ray photoelectron spectra of pristine and post-CMO electrode highlights that the reversible conversion of Mn^(3+)/Mn^(4+)couple is resulted from the intercalation/de-intercalation of Na^(+),while this is irreversible for Co^(3+)/Co^(2+)couple.Beyond that,the CMO electrode has been proven the selectivity removal of Na^(+) over K^(+)and Mg^(2+)in a multi-cation stream.展开更多
基金the financial support from Shenzhen Science and Technology Program (JCYJ20210324142210027, X.D.)the National Natural Science Foundation of China (52103136, 22275028, U22A20153, 22102017, 22302033, and 52106194)+5 种基金the Sichuan Outstanding Young Scholars Foundation (2021JDJQ0013)Natural Science Foundation of Sichuan Province (2022NSFSC1271)Sichuan Science and Technology Program (2023JDRC0082)“Oncology Medical Engineering Innovation Foundation” project of University of Electronic Science and Technology of China and Sichuan Cancer Hospital (ZYGX2021YGCX009)“Medical and Industrial Cross Foundation” of University of Electronic Science and Technology of China and Sichuan Provincial People’s Hospital (ZYGX2021YGLH207)Shandong Key R&D grant (2022CXGC010509)。
文摘Superhydrophobic surface(SHS) has been well developed, as SHS renders the property of minimizing the water/solid contact interface. Water droplets deposited onto SHS with contact angles exceeding 150°, allow them to retain spherical shapes, and the low adhesion of SHS facilitates easy droplet collection when tilting the substrate. These characteristics make SHS suitable for a wide range of applications. One particularly promising application is the fabrication of microsphere and supraparticle materials. SHS offers a distinct advantage as a universal platform capable of providing customized services for a variety of microspheres and supraparticles. In this review, an overview of the strategies for fabricating microspheres and supraparticles with the aid of SHS, including cross-linking process, polymer melting,and droplet template evaporation methods, is first presented. Then, the applications of microspheres and supraparticles formed onto SHS are discussed in detail, for example, fabricating photonic devices with controllable structures and tunable structural colors, acting as catalysts with emerging or synergetic properties, being integrated into the biomedical field to construct the devices with different medicinal purposes, being utilized for inducing protein crystallization and detecting trace amounts of analytes. Finally,the perspective on future developments involved with this research field is given, along with some obstacles and opportunities.
基金supported by Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province Human Resource Training Project(HRTP-[2022]-53).
文摘The optical diffraction effect imposes a radical obstacle preventing conventional optical microscopes from achieving an imaging resolution beyond the Abbe diffraction limit and thereby restricting their usage in a multitude of nanoscale applications.Over the past decade,the optical microsphere nanoimaging technique has been demonstrated to be a cost-effective solution for overcoming the diffraction limit and has achieved an imaging resolution of up to about k6k8 in a real-time and label-free manner,making it highly competitive among numerous super-resolution imaging technologies.In this review,we summarize the underlying nano-imaging mechanisms of the microsphere nanoscope and key advancements aimed at imaging performance enhancement:first,to change the working environment or modify the peripheral hardware of a single microsphere nanoscope at the system level;second,to compose the microsphere compound lens;and third,to engineer the geometry or ingredients of microspheres.We also analyze challenges yet to be overcome in optical microsphere nano-imaging,followed by an outlook of this technique.
基金Funded by the Jiangsu Province Industry-University-Research Cooperation Project (No.BY2018314)the Scientific Research Foundation of Jiangsu University of Technology (No.KYY18030)Jiangsu Overseas Visiting Scholar Program for University Prominent Young&Middle-aged Teachers and Presidents。
文摘3D hierarchical flowerlike WS_(2) microspheres were synthesized through a facile one-pot hydrothermal route.The as-synthesized samples were characterized by powder X-ray powder diffraction (XRD),energy-dispersive spectroscopy (EDS),scanning electron microscopy (SEM) and Raman.SEM images of the samples reveal that the hierarchical flowerlike WS_(2) microspheres with diameters of about 3-5μm are composed of a number of curled nanosheets.Electrochemical tests such as charge/discharge,cyclic voltammetry,cycle life and rate performance were carried out on the WS_(2) sample.As an anode material for lithium-ion batteries,hierarchical flowerlike WS_(2) microspheres show excellent electrochemical performance.At a current density of100 mA·g^(-1),a high specific capacity of 647.8 mA·h·g^(-1) was achieved after 120 discharge/charge cycles.The excellent electrochemical performance of WS_(2) as an anode material for lithium-ion batteries can be attributed to its special 3D hierarchical structure.
基金supported by the Open Fund of Shaanxi Key Laboratory of Advanced Stimulation Technology for Oil&Gas Reservoirs(No.KFJJ-TZ-2020-2)the National Natural Science Foundation of China(No.52104030)+1 种基金the Key Research and Development Program of Shaanxi(No.2022 KW-35)the China Fundamental Research Funds for the Central Universities。
文摘Polymer microspheres(PMs),such as polyacrylamide,have been widely applied for enhanced oil recovery(EOR),yet with environmental concerns.Here,we report a microfluid displacement technology containing a bio-based eco-friendly material,i.e.,calcium alginate(CaAlg)microspheres for EOR.Two dominant mechanisms responsible for EOR over Ca Alg fluid have been verified,including the microscopic oil displacement efficacy augmented by regulating capillary force(determined by the joint action of interfacial tension and wettability between different phases)and macroscopic sweep volume increment through profile control and mobility ratio reduction.This comprehensive effectiveness can be further impacted when the CaAlg microsphere is embellished ulteriorly by using appropriate amount of sodium dodecyl sulfonate(SDS).The core flooding and nuclear magnetic resonance(NMR)tests demonstrate that CaAlg-SDS microsphere can balance the interphase property regulation(wettability alteration and IFT reduction)and rheology properties,enabling simultaneous profile control and oil displacement.Excessive introduction of SDS will have a negative impact on rheological properties,which is not favored for EOR.Our results show that the involvement of 4-m M SDS will provide the best behavior,with an EOR rate of 34.38%.This cost-effective and environmentally-friendly bio-microspherebased microfluidic displacement technology is expected to achieve“green”oil recovery in future oilfield exploitation.
基金supported by grants from the CAMS Innovation Fund for Medical Sciences(2021-I2M-1-052)Tianjin Natural Science Foundation for Jingjinji Collaboration(23JCZXJC00240)+2 种基金Capital's Funds for Health Improvement and Research(CFH:2022-2-5072)Tianjin Hospital Fund for Science and Technology(Tjyy2109)the Open Fund of Tianjin Key Laboratory of Biomedical Materials(2022BMEKFKT002)。
文摘Background:In facial plastic surgery,patients with nasal deformity are often treated by rib cartilage transplantation.In recent years,cartilage tissue engineering has developed as an alternative to complex surgery for patients with minor nasal defects via injection of nasal filler material.In this study,we prepared an injectable nasal filler material containing poly-L-l actic acid(PLLA)porous microspheres(PMs),hyaluronic acid(HA)and adipose-derived mesenchymal stem cells(ADMSCs).Methods:We seeded ADMSCs into as-prepared PLLA PMs using our newly invented centrifugation perfusion technique.Then,HA was mixed with ADMSC-i ncorporated PLLA PMs to form a hydrophilic and injectable cell delivery system(ADMSCincorporated PMH).Results:We evaluated the biocompatibility of PMH in vitro and in vivo.PMH has good injectability and provides a favorable environment for the proliferation and chondrogenic differentiation of ADMSCs.In vivo experiments,we observed that PMH has good biocompatibility and cartilage regeneration ability.Conclusion:In this study,a injectable cell delivery system was successfully constructed.We believe that PMH has potential application in cartilage tissue engineering,especially in nasal cartilage regeneration.
基金supported by the National Natural Science Foundation of China(52231007,12327804,T2321003,22088101)this work was supported in part by the National Key Research Program of China under Grant 2021YFA1200600,and Shanghai Sailing Program(22YF1447800).
文摘Broadband electromagnetic(EM)wave absorption materials play an important role in military stealth and health protection.Herein,metal–organic frameworks(MOFs)-derived magnetic-carbon CoNiM@C(M=Cu,Zn,Fe,Mn)microspheres are fabricated,which exhibit flower-like nano–microstructure with tunable EM response capacity.Based on the MOFs-derived CoNi@C microsphere,the adjacent third element is introduced into magnetic CoNi alloy to enhance EM wave absorption performance.In term of broadband absorption,the order of efficient absorption bandwidth(EAB)value is Mn>Fe=Zn>Cu in the CoNiM@C microspheres.Therefore,MOFs-derived flower-like CoNiMn@C microspheres hold outstanding broadband absorption and the EAB can reach up to 5.8 GHz(covering 12.2–18 GHz at 2.0 mm thickness).Besides,off-axis electron holography and computational simulations are applied to elucidate the inherent dielectric dissipation and magnetic loss.Rich heterointerfaces in CoNiMn@C promote the aggregation of the negative/positive charges at the contacting region,forming interfacial polarization.The graphitized carbon layer catalyzed by the magnetic CoNiMn core offered the electron mobility path,boosting the conductive loss.Equally importantly,magnetic coupling is observed in the CoNiMn@C to strengthen the magnetic responding behaviors.This study provides a new guide to build broadband EM absorption by regulating the ternary magnetic alloy.
基金supported by the Fund of State Key Laboratory of Deep Oil and Gas,China University of Petroleum (East China) (SKLDOG2024-ZYRC-06)Key Program of National Natural Science Foundation of China (52130401)+2 种基金National Natural Science Foundation of China (52104055,52250410349)Major Science and Technology Project of China National Petroleum Corporation Limited (2021ZZ01-08)Shandong Provincial Natural Science Foundation,China (ZR2021ME171)。
文摘CO_(2) flooding is a vital development method for enhanced oil recovery in low-permeability reservoirs,However,micro-fractures are developed in low-permeability reservoirs,which are essential oil flow channels but can also cause severe CO_(2) gas channeling problems.Therefore,anti-gas channeling is a necessary measure to improve the effect of CO_(2) flooding.The kind of anti-gas channeling refers to the plugging of fractures in the deep formation to prevent CO_(2) gas channeling,which is different from the wellbore leakage.Polymer microspheres have the characteristics of controllable deep plugging,which can achieve the profile control of low-permeability fractured reservoirs.In acidic environments with supercritical CO_(2),traditional polymer microspheres have poor expandability and plugging properties.Based on previous work,a systematic evaluation of the expansion performance,dispersion rheological properties,stability,deep migration,anti-CO_(2) channeling and enhanced oil recovery ability of a novel acid-resistant polymer microsphere(DCNPM-A)was carried out under CQ oilifield conditions(salinity of85,000 mg/L,80℃,pH=3).The results show that the DCNPM-A microsphere had a better expansion performance than the traditional microsphere,with a swelling rate of 13.5.The microsphere dispersion with a concentration of 0.1%-0.5%had the advantages of low viscosity,high dispersion and good injectability in the low permeability fractured core.In the acidic environment of supercritical CO_(2),DCNPM-A microspheres showed excellent stability and could maintain strength for over 60 d with less loss.In core experiments,DCNPM-A microspheres exhibited delayed swelling characteristics and could effectively plug deep formations.With a plugging rate of 95%,the subsequent enhanced oil recovery of CO_(2) flooding could reach 21.03%.The experimental results can provide a theoretical basis for anti-CO_(2)channeling and enhanced oil recovery in low-permeability fractured reservoirs.
文摘[Objectives]This study was conducted to investigate the effects of slow-release nitrogen fertilizer on dry matter accumulation and translocation of summer maize.[Methods]With Zhoudan 9 as the test variety,six different treatment were set up:blank control(CK1),slow-release urea 75 kg/hm^(2)(C1),slow-release urea 150 kg/hm^(2)(C2),slow-release urea 225 kg/hm^(2)(C3),slow-release urea 300 kg/hm^(2)(C4)and ordinary urea 300 kg/hm^(2)(CK2),to study the change law of dry matter accumulation and translocation in summer maize.[Results]Treatment slow-release urea 225 kg/hm^(2)(C4)showed summer maize yield,dry matter translocation between organs,grain contribution rate and proportion of grain dry matter in the full ripe stage higher than other treatments.Considering the weight loss and cost factors,slow-release urea 225 kg/hm^(2)(C3)could be recommended as the fertilizing amount for summer maize.[Conclusions]This study provides theoretical reference for rational selection of fertilizers for reducing fertilizer application and increasing fertilizer efficiency,and for production of summer maize in Shajiang black soil region.
基金Supported by Scientific Research project of Hunan Provincial Health Commission,No.B202303077689Hunan Natural Science Foundation Project,No.2023JJ40397.
文摘BACKGROUND Transhepatic arterial chemoembolization(TACE),as a local treatment,has been widely used in the treatment of unresectable liver cancer.The introduction of drug carrier microspheres has brought new hope for the therapeutic effect of TACE.Microspheres can realize the slow release and directional delivery of drugs,reduce systemic toxicity and improve local curative effect.AIM To compare the effectiveness of traditional transcatheter arterial chemoembolization against microsphere-assisted transcatheter arterial chemoembolization in the treatment of hepatocellular carcinoma that is incurable.METHODS We searched the PubMed,Embase,Cochrane Library,and CNKI databases for clinical trials of drug-luting beads TACE(DEB-TACE)vs conventional TACE(cTACE)for the treatment of unresectable liver cancer.We screened references based on inclusion and exclusion criteria and then selected valid data for meta-analysis using RevMan 53 software.The complete response(CR)rate,partial response(PR)rate,postoperative stable disease(SD)rate,and 6-month and 12-month survival rates were compared.RESULTS A total of 12 articles were included,including 1177 patients,519 of whom received DEB-TACE and 658 of whom received cTACE.The CR rate in the DEB-TACE group was much greater than that in the cTACE group[relative risk(RR)=1.42,95%CI:1.18-1.72,P=0.0002].The 12-month survival rate significantly increased(RR=1.09;95%CI:1.01-1.17,P=0.03);the PR rate(RR=1.13;95%CI:0.97-1.30,P=0.12);the SD rate(RR=0.82;95%CI:0.64-1.05,P=0.12);and the 6-month survival rate(RR=1.05;95%CI:1.00-1.10,P=0.07).There was no significant difference(P<0.05).CONCLUSION Compared with those of iodized oil TACE,the drug-loaded microspheres tended to have therapeutic advantages.
基金Supported by National Key Research and Development Program of China(2017FYD0101406)Zhoukou Comprehensive Test Station of Henan Provincial Corn Industry Technology System(HARS-22-02-Z5)。
文摘[Objectives] This study was conducted to verify the field application effect of slow-release nitrogen fertilizer on summer maize in Shajiang black soil area by simultaneous sowing and fertilization, and explore the application scope and nitrogen metabolism mechanism, so as to lay a foundation for fertilizer reduction and efficiency improvement. [Methods] With maize variety Beiqing 340 and sulfur-coated urea as experimental materials, five nitrogen application levels were set, namely, control (C0), slow-release nitrogen 70 kg/hm^(2) (C70), slow-release nitrogen 140 kg/hm^(2) (C140), slow-release nitrogen 210 kg/hm^(2) (C210) and slow-release nitrogen 280 kg/hm^(2) (C280). The phosphorus and potassium fertilizers were all in accordance with the unified standard. [Results] With the application rate of slow-release nitrogen increasing, the nitrogen accumulation in organs increased first and then decreased after tasseling stage of maize. In order to reduce the fertilizing amount and increase efficiency, 210 kg/hm^(2) of slow-release nitrogen fertilizer was the best fertilizing amount for summer maize in Shajiang black soil area. [Conclusions] This study provides reference for fertilizer reduction, efficiency improvement and sustainable development of summer maize in Shajiang black soil area.
基金the National Natural Science Foundation of China(Grant Nos.T2222027,12202416 and 12272359).
文摘Metal(aluminum and boron)based energetic materials have been wildly applied in various fields including aerospace,explosives and micro-devices due to their high energy density.Unfortunately,the low combustion efficiency and reactivity of metal fuels,especially boron(B),severely limit their practical applications.Herein,multi-component 3D microspheres of HMX/B/Al/PTFE(HBA)have been designed and successfully prepared by emulsion and solvent evaporation method to achieve superior energy and combustion reactivity.The reactivity and energy output of HBA are systematically measured by ignitionburning test,constant-volume explosion vessel system and bomb calorimetry.Due to the increased interfacial contact and reaction area,HBA shows higher flame propagation rate,faster pressurization rate and larger combustion heat of 29.95 cm/s,1077 kPa/s,and 6164.43 J/g,which is 1.5 times,3.5 times,and 1.03 times of the physical mixed counterpart(HBA-P).Meanwhile,HBA also shows enhanced energy output and reactivity than 3D microspheres of HMX/B/PTFE(HB)resulting from the high reactivity of Al.The reaction mechanism of 3D microspheres is comprehensively investigated through combustion emission spectral and thermal analysis(TG-DSC-MS).The superior reactivity and energy of HBA originate from the surface etching of fluorine to the inert shell(Al_(2)O_(3) and B_(2)O_(3))and the initiation effect of Al to B.This work offers a promising approach to design and prepare high-performance energetic materials for the practical applications.
基金National Natural Science Foundation of China(81560659)General Program of Natural Science Foundation of Jiangxi Province(2023BAB206169)+2 种基金Science and Technology Research Project of Jiangxi Provincial Department of Education(GJJ2200903&GJJ2200952)Science and Technology Plan of Jiangxi Provincial Health Commission(202211411)National College Students Innovation and Entrepreneurship Training Program(202310412028&202110412041).
文摘[Objectives]To optimize the formulation and preparation of oregano oil microspheres by Box-Behnken response surface methodology.[Methods]Chitosan was used as the carrier material to prepare oregano oil microspheres by emulsion crosslinking method.The encapsulation efficiency,drug loading and ID 50 were used as the evaluation indicators,and the comprehensive score(OD)obtained by"coefficient of variation-AHP comprehensive weighting method"was used as the final evaluation indicator.The formulation design and preparation process were optimized by single factor experiment and Box-Behnken response surface methodology,and the optimal process parameters were determined.[Results]The optimal formulation and preparation process parameters of oregano oil microspheres were as follows:the ratio of oregano oil to chitosan was 2∶1,the emulsifying speed of double emulsion was 200 r/min,the amount of emulsifier in the colostrum was 4%,and the volume of curing agent was 1.0 mL.The average encapsulation efficiency was 45.33%±1.32%,the average drug loading was 30.59%±2.45%,and the median diameter(ID 50)was 52.596μm±0.023%.[Conclusions]The encapsulation efficiency,drug loading and ID 50 of oregano oil chitosan microspheres prepared by emulsion crosslinking method met the requirements.The drug-loaded microsphere not only can be used as a preparation finished product for direct application,but also be used as a product intermediate to lay a foundation for the research and development of subsequent dosage forms.
文摘A wound care system consisting of ciprofloxacin-loaded gelatin microspheres impregnated in a macroporous collagen scaffold was created to effectively control wound infection and regenerate soft tissue at the wound site.Histological and biochemical alterations were observed in infected wounds treated with these scaffolds in Albino Wistar rats.Furthermore,the study examined the immediate and prolonged release of ciprofloxacin from the scaffolds,as well as their function in eliminating bacterial infections and expediting the process of skin healing and regeneration.The developed technique was followed in the streamlined process of creating these collagen scaffolds.Compared to untreated wounds,the group receiving scaffold treatment experienced a faster rate of wound closure.It was noted that the rate of infections was considerably reduced and that full soft tissue regeneration occurred within 12 days.The development of well-deposited collagen bundles in the treated groups was demonstrated by H&E staining,which verified the flawless regeneration of the dermis and epidermis.The antimicrobial agent-loaded gelatin microspheres impregnated into the porous collagen scaffold demonstrated remarkable soft tissue regeneration and efficient infection control at the wound site.
文摘Microspheres are a new type of drug carrier with great potential for development and application.Natural polymers have good biocompatibility,biodegradability,and are easily dispersed in living organisms,making them suitable for preparing microspheres.Inorganic materials(mainly inorganic minerals)have excellent mechanical properties and are inexpensive and easy to obtain.Through the coupling and hybridization of natural polymers and inorganic materials,they can complement each other's advantages and synergistically enhance efficiency,resulting in many excellent physical and chemical properties.Inorganic materials/natural polymer composite microspheres can be prepared by modifying natural polymers with inorganic materials through various methods such as emulsification crosslinking,solution mixing,in-situ synthesis,extrusion,etc.The application of inorganic materials/natural polymer composite microspheres in drug delivery systems has significant sustained-release effects,is safe and non-toxic,and the cost of carrier materials is relatively low,which has certain significance for the development of new drug carriers.This article reviews the recent research on the preparation,drug loading and release properties of inorganic material/natural polymer composite microspheres,analyzes the advantages and disadvantages of commonly used preparation methods,and looks forward to the development direction of composite microspheres.
基金Natural Science Foundation of Guangdong Province (No.05006556).
文摘Functional porous microspheres used for the slow release carrier of actives in cosmetics or pharmaceuticals were prepared by modified suspension polymerization of styrene (ST) with divinylbenzene (DVB) in the presence of toluene, cyclohexanol and heptane as porogenic diluents. The use of ultrasonic dispersion decreases the beads' size and improves the uniformity. The effects of the porogen mixture, DVB content and solvent extraction on the surface performance of the synthesized beads were studied. The microspheres were characterized by scanning electron microscopy (SEM) and BET surface area determination. It was found that a great proportion of the non-solvating porogen increases the pore diameter and the specific surface area. High DVB concentration also results in the great specific surface area and porosity. When the ratio of toluene/cyclohexanol is 1:2, DVB content is at the range of 40%-60% and methylene chloride was used as extractant, the beads with good spherical shape and pore size were obtained. The prepared porous microspheres were applied as active carriers and showed satisfactory slow release effect. Over 10h constantly sustained release was observed in vitro releasing test for hydroquinone-loaded microspheres. Great surface area promoted high concentration of released hydroquinone.
基金Supported by Natural Science Foundation of Guangdong Province (No.05006556).
文摘Functional porous microspheres used for the slow release carrier of actives in cosmetics or pharmaceu- ticals were prepared by modified suspension polymerization of styrene (ST) with divinylbenzene (DVB) in the presence of toluene, cyclohexanol and heptane as porogenic diluents. The use of ultrasonic dispersion decreases the beads’ size and improves the uniformity. The effects of the porogen mixture, DVB content and solvent extraction on the surface performance of the synthesized beads were studied. The microspheres were characterized by scanning electron microscopy (SEM) and BET surface area determination. It was found that a great proportion of the non-solvating porogen increases the pore diameter and the specific surface area. High DVB concentration also re- sults in the great specific surface area and porosity. When the ratio of toluene/cyclohexanol is 1:2, DVB content is at the range of 40%—60% and methylene chloride was used as extractant, the beads with good spherical shape and pore size were obtained. The prepared porous microspheres were applied as active carriers and showed satisfactory slow release effect. Over 10h constantly sustained release was observed in vitro releasing test for hydro- quinone-loaded microspheres. Great surface area promoted high concentration of released hydroquinone.
基金financially supported by National Natural Science Foundation of China (22068018)Yunnan Ten Thousand Talents Plan Young & Elite Talents Project。
文摘Drug-loaded microspheres are significant for the development of modern pharmaceutical products. It is well known that the taken of aspirin for long-term increases the risk of serious gastrointestinal complications, therefore a controllable delivery of aspirin is of importance to lighten those side effects. In this work, poly(lactic acid)(PLA) was chosen as the carrier to prepare PLA-aspirin microspheres by using the traditional and the improved solvent evaporation methods. It was found that no matter which experimental condition was, the encapsulation efficiency of aspirin was higher by using the improved method than that of the traditional method. Specifically, when the concentration of polyvinyl alcohol = 1%(mass),the polymer concentration = 1:20, the oil/water rate = 1:2.5, PLA-aspirin microspheres were obtained via the improved method with a high yield of 82.83%(mass) and an encapsulation efficiency of 44.09%. PLAaspirin microspheres were then prepared continuously using the improved method, which further enhanced the encapsulation efficiency to 54.56%. Approximate 85% aspirin released from microspheres within 7 days. Obvious degradation which was represented by reduction on hardness was observed by soaking microspheres in PBS for 60 days. This work is of interest because it provides a continuous route to prepare PLA-aspirin microspheres continuously with a high drug encapsulation efficiency.
基金supported by Zhejiang Provincial Key Research and Development Program(2021C01004)National Key Research and Development Program of China(No.2021YFE0100500,2021YFB3501504)Zhejiang Provincial Natural Science Foundation(LQ22E030003),Guangdong Basic and Applied Basic Research Foundation(2020A1515110005).
文摘Multi-layer 2D material assemblies provide a great number of interfaces beneficial for electromagnetic wave absorption.However,avoiding agglomeration and achieving layer-by-layer ordered intercalation remain chal-lenging.Here,3D reduced graphene oxide(rGO)/MXene/TiO_(2)/Fe_(2)C lightweight porous microspheres with periodical intercalated structures and pronounced inter-facial effects were constructed by spray-freeze-drying and microwave irradiation based on the Maxwell–Wagner effect.Such approach reinforced interfacial effects via defects introduction,porous skeleton,multi-layer assembly and multi-compo-nent system,leading to synergistic loss mechanisms.The abundant 2D/2D/0D/0D intercalated heterojunctions in the microspheres provide a high density of polari-zation charges while generating abundant polarization sites,resulting in boosted interfacial polarization,which is verified by CST Microwave Studio simulations.By precisely tuning the 2D nanosheets intercalation in the heterostructures,both the polarization loss and impedance matching improve significantly.At a low filler loading of 5 wt%,the polarization loss rate exceeds 70%,and a minimum reflection loss(RLmin)of-67.4 dB can be achieved.Moreover,radar cross-section simulations further confirm the attenuation ability of the optimized porous microspheres.These results not only provide novel insights into understanding and enhancing interfacial effects,but also constitute an attractive platform for implementing heterointerface engineering based on customized 2D hierarchical architectures.
基金This work is supported by Academic Research Fund Tier 2,Ministry of Education-Singapore(MOE2019-T2-2-147)T.C.acknowledges support from the National Key Research and Development Program of China(2019YFA0709100,2020YFA0714504).
文摘Creation of arbitrary features with high resolution is critically important in the fabrication of nano-optoelectronic devices.Here,sub-50 nm surface structuring is achieved directly on Sb2S3 thin films via microsphere femtosecond laser irradi-ation in far field.By varying laser fluence and scanning speed,nano-feature sizes can be flexibly tuned.Such small patterns are attributed to the co-effect of microsphere focusing,two-photons absorption,top threshold effect,and high-repetition-rate femtosecond laser-induced incubation effect.The minimum feature size can be reduced down to~30 nm(λ/26)by manipulating film thickness.The fitting analysis between the ablation width and depth predicts that the feature size can be down to~15 nm at the film thickness of~10 nm.A nano-grating is fabricated,which demonstrates desirable beam diffraction performance.This nano-scale resolution would be highly attractive for next-generation laser nano-lithography in far field and in ambient air.
基金This work was supported by the National Natural Science Foundation of China (No.21862016)Project of Ningxia key R&D plan (No.2017BY064).
文摘The“battery type”inorganic electrode has been demonstrated the highly efficient sodium ion intercalation capacity for capacitive deionization.In this work,the CoMn_(2)O_(4)(CMO)microspheres with porous core-shell structure are prepared via co-precipitation and followed by annealing.The effects of annealing temperatures on the morphology,pore structure,valence state,and electrochemical behavior of CMO are explored.As electrode for capacitive deionization,the salt removal capacity and current efficiency of optimized AC||CMO device reaches up to 60.7 mg g^(−1) and 97.6%,respectively,and the capacity retention rate is 74.1%after 50 cycles.Remarkably,both the in-situ X-ray diffraction and ex-situ X-ray diffraction analysis features that the intercalation/de-intercalation of sodium ions are governed by(103)and(221)crystal planes of CMO.Accordingly,the density functional theory calculations realize that the adsorption energies of Na+onto(103)and(221)crystal planes are higher than that of any other crystal planes,manifesting the priorities in adsorption of sodium atoms.Furthermore,the X-ray photoelectron spectra of pristine and post-CMO electrode highlights that the reversible conversion of Mn^(3+)/Mn^(4+)couple is resulted from the intercalation/de-intercalation of Na^(+),while this is irreversible for Co^(3+)/Co^(2+)couple.Beyond that,the CMO electrode has been proven the selectivity removal of Na^(+) over K^(+)and Mg^(2+)in a multi-cation stream.