Elemental calcium plays an important role in human physiology. In order to study the relationship between Ca-intake, Ca-chemical formulation, and Ca-absorptivity, a balance experiment using a ^(41)Ca tracer technique ...Elemental calcium plays an important role in human physiology. In order to study the relationship between Ca-intake, Ca-chemical formulation, and Ca-absorptivity, a balance experiment using a ^(41)Ca tracer technique in SD rats was conducted to measure the endogenous fecal calcium and true absorption of calcium. Apparent absorption of calcium was measured as a control to the endogenous calcium labeling experiment. These results show that by using ^(41)Ca labeled endogenous calcium in vivo, researchers could obtain the true calcium absorption data without extrinsic labeling. Therefore, the method was not affected by the chemical structure or type of calcium supplement and might be used in evaluating the absorptivity of marketed calcium supplements.展开更多
When the thermal environment is under heated conditions, short-wavelength solar radiation shows a strong influence on the human body and the heat is accumulated in the human body. In order to demonstrate the effect of...When the thermal environment is under heated conditions, short-wavelength solar radiation shows a strong influence on the human body and the heat is accumulated in the human body. In order to demonstrate the effect of the short-wavelength solar radiation absorptivity of clothing on physiological temperature in an outdoor space, the relationship between the thermal environment evaluation index, ETFe, and the thermal sensory perceptions of the human body was investigated. A significant temperature difference of 2.7°C was shown for an ETFe that was thermally neutral (neither hot nor cold). The effect of short-wavelength solar radiation absorptivity was strongly apparent in ETFe when direct solar radiation was strong and in warmer outdoor spaces. In an outdoor space where the effect of the sky factor and albedo was strong, the setting of the short-wavelength solar radiation absorptivity was demonstrated to greatly impact the estimation of perceived and physiological temperature. When interviewing subjects on clothing in an outdoor space, it is essential to obtain the hue of clothing.展开更多
The mathematical equations of the effective percentage of a complexant and ite complex-ratio with a metal have been developed by means of the β-correction pinciple. From a real absorbance of the chelate produced,its ...The mathematical equations of the effective percentage of a complexant and ite complex-ratio with a metal have been developed by means of the β-correction pinciple. From a real absorbance of the chelate produced,its true absorptivity can be determined accurately. The β-correction spectrophotometry was studied for the determinations of the desired parameters above, using the reaction of lead with Eriochrome Black T(EBT) at pll 8.2. The results show that the analytical sensitivity and precision by β-correction method are both mucb higher than those by the single wavelength method, the complex-ratio of Pb(Ⅱ) with EBT equals to 1:4 and the true molar absorptivity of Pb(EBT)4 chelate at 550 nm is 3.52,104 L.mol-1.cm-1.展开更多
Choosing two different elements of rare earth, the absorptivity of them on copper and its alloys were researched from the category of rare earth, melting point, adding methods, casting temperature, time of heat preser...Choosing two different elements of rare earth, the absorptivity of them on copper and its alloys were researched from the category of rare earth, melting point, adding methods, casting temperature, time of heat preservation, quantity of rare earth additives etc. The laws of affecting the absorptivity are found through the research. The distributing of rare earth, existent state and the formed compounds on copper and its alloys were observed in the casting state. The absorptivities of rare earth on copper and its alloys were analyzed.展开更多
The molar absorption coefficients of each of 14 kinds of amino acids were determined by the spectrophotometric method, and the mean molar absorption coefficients of 37 different mixtures of each with amino acid compos...The molar absorption coefficients of each of 14 kinds of amino acids were determined by the spectrophotometric method, and the mean molar absorption coefficients of 37 different mixtures of each with amino acid composition exactly equivalent to that of the peptide chain of the corresponding lipopeptide were determined based on calculation or experimental. The significance of the results is that the mean molar absorption coefficients strongly demonstrate the regular patterns, though different amino acids bear quite different molar absorption coefficients.展开更多
Background:Traditional Chinese medicine involves complex ingredients and mixtures of ingredients that often exhibit low bioavailability,and excipients are often lacking to increase the absorption-enhancing effects.Thi...Background:Traditional Chinese medicine involves complex ingredients and mixtures of ingredients that often exhibit low bioavailability,and excipients are often lacking to increase the absorption-enhancing effects.This study modified the generation 4 polyamidoamine dendrimer with polyethylene glycol of different molecular weights(5000,2000,1000)to form a series of polyamidoamine-co-polyethylene glycol(PAMAM-co-PEG)as a novel class of oral absorption enhancers.Evodiamine,the major alkaloid found in the traditional Chinese medicine Wu Zhu Yu(Fructus Evodiae),was used as a model drug to verify the absorption-enhancing effects and the safety of this alkaloid.Methods:This study utilized the solubility determination method documented in the Pharmacopoeia of the People’s Republic of China(2015 edition)and the D0 values recommended in the US FDA guidelines to comprehensively evaluate the solubility of evodiamine.The permeability of evodiamine was assessed using the apparent permeability coefficient in experiments based on in vitro cell models.Multiple aspects of the biological safety of PAMAM-co-PEG were explored using the MTT assay,LDH assay,and total protein release of the rat intestinal tract.Moreover,the absorption-enhancing effects of PAMAM-co-PEG at different molecular weights on evodiamine were verified via the use of in vitro cell models and in vivo intestinal loop circulation experiments with rats.Results:Evodiamine exhibited low solubility and permeability and was classified into class IV compounds using the biopharmaceutical classification system.PAMAM-co-PEG 2000 demonstrated improvement in the biosafety and absorption-enhancement effect of evodiamine at a specific concentration.This study showed that 0.05%(w/v)of PAMAM-co-PEG 2000 increased the cumulative penetration of evodiamine via cell transport by 1.32 times,and 0.10%(w/v)of PAMAM-co-PEG 2000 increased the area under curve value of evodiamine by 1.31 times.Conclusion:Evodiamine possesses low solubility and permeability and leads to poor oral bioavailability and a certain degree of cytotoxicity.PAMAM-co-PEG 2000 was found to be a potentially safe and efficient oral absorption enhancer.The results of this study might create a foundation for the development of novel excipients suitable for the complex active ingredients of traditional Chinese medicine.展开更多
Background:Excessive use of inorganic trace minerals(ITMs)in swine production leads to high fecal mineral excretion and environmental risks,while most studies on organic trace minerals(OTMs)focus on single elements,wi...Background:Excessive use of inorganic trace minerals(ITMs)in swine production leads to high fecal mineral excretion and environmental risks,while most studies on organic trace minerals(OTMs)focus on single elements,with limited data on the synergistic effects and molecular mechanisms of combined OTMs(Fe,Cu,Mn,Zn)in growing-finishing pigs.Methods:This study aimed to investigate the effects of graded levels of micromineral proteinates(combined OTMs)on growth performance,mineral metabolism,and mRNA expression of mineral regulatory proteins.A total of 360 crossbred Duroc×Landrace×Large White pigs(initial body weight 47.1±4.8 kg)were randomly assigned to 6 dietary treatments:basal diet without microminerals(CON),basal diet with ITMs at commercially recommended levels(IT),and basal diets with 15%(OT 15%),25%(OT 25%),35%(OT 35%)commercially recommended levels(CRL)of combined micromineral proteinates.After a 70-day feeding trial,samples were analyzed using ICP-OES,ELISA,and RT-qPCR.Results:Results showed that reduced levels(15-35%CRL)of micromineral proteinates did not significantly affect average daily gain,average daily feed intake,or feed conversion ratio(gain-to-feed ratio)compared to IT(P>0.05),but significantly increased plasma Cu(1.73-1.83μg/mL)and Zn(1.72-1.97μg/mL)concentrations(P<0.05)and elevated activities of Cu/Zn-superoxide dismutase(32.9-35.9 U/L)and manganese superoxide dismutase(20.5-24.1 U/L)compared to CON(P<0.05),with no significant differences from IT(P>0.05).Fecal excretion of Fe,Cu,Mn,and Zn was significantly reduced by 35-50%in OT 15%-OT 35%groups compared to IT(P<0.05).OT 25%group exhibited the highest apparent absorptivity of Fe(38.5%),Cu(27.8%),and Zn(42.4%)(P<0.05),which was associated with significantly regulated mRNA expression of mineral regulatory proteins:upregulated DMT1,FPN1,ZIP4,and MT1A in the duodenum,and modulated HAMP,ATP7B,ZIP14,and ZnT1 in the liver(P<0.05).Conclusion:In conclusion,dietary supplementation with 25%CRL or less of combined micromineral proteinates can fully meet the nutritional needs of growing-finishing pigs,improve mineral absorptivity,and reduce fecal mineral excretion by regulating intestinal and hepatic mineral transport and homeostatic proteins,providing a sustainable alternative to high-dose ITMs.展开更多
With the rapid development of modern electronic technology,the demand for high-performance microwave absorption materials has increased dramatically.In order to meet this demand,the electrospinning of FeNiCo/carbon na...With the rapid development of modern electronic technology,the demand for high-performance microwave absorption materials has increased dramatically.In order to meet this demand,the electrospinning of FeNiCo/carbon nanofiber(FeNiCo/CNF)composites with excellent microwave absorption properties was developed,and their potential as high frequency microwave absorption materials was evaluated.Experiment showed that FeNiCo/CNFs achieve a minimum reflection loss(RL_(min))of−55.5 dB with a matching thickness of only 1.6 mm.Microstructure analysis and electromagnetic parameter testing showed that the excellent microwave absorbing properties were mainly due to the combined effect of the network structure of carbon nanofibers and the FeNiCo alloy.This interaction promotes multiple reflections and the efficient absorption of microwaves.Computer simulation also showed that the FeNiCo/CNF composites produce an excellent radar cross-section reduction in typical radar operating frequency bands,which validates their potential application in stealth technology.This is a new concept in the development of high-performance microwave absorption materials.展开更多
This study systematically investigated the influence of deposition rate on the structure,broadband opti⁃cal properties(1.0-13.0μm),and stress characteristics of Germanium(Ge)films.Additionally,a method for enhancing ...This study systematically investigated the influence of deposition rate on the structure,broadband opti⁃cal properties(1.0-13.0μm),and stress characteristics of Germanium(Ge)films.Additionally,a method for enhancing the performance of infrared filters based on rate-modulated deposition of Ge films was proposed.The optical absorption of Ge films in the short-wave infrared(SWIR)and long-wave infrared(LWIR)bands can be effectively reduced by modulating the deposition rate.As the deposition rate increases,the Ge films maintain an amorphous structure.The optical constants of the films in the 1.0-2.5μm and 2.5-13.0μm bands were precisely determined using the Cody-Lorentz model and the classical Lorentz oscillator model,respectively.Notably,high⁃er deposition rates result in a gradual increase in the refractive index.The extinction coefficient increases with the deposition rate in the SWIR region,attributed to the widening of the Urbach tail,while it decreases in the LWIR region due to the reduced absorption caused by the Ge-O stretching mode.Additionally,the films exhibit a tensile stress that decreases with increasing deposition rate.Finally,the effectiveness of the proposed fabrication method for an infrared filter with Ge films deposited at an optimized rate was demonstrated through practical examples.This work provides theoretical and technical support for the application of Ge films in high-performance infrared filters.展开更多
The development of materials with excellent microwave absorption(MWA)and electromagnetic interference(EMI)shielding performances has currently received attention.Herein,mesophase pitch-based carbon foam(MPCF)with 3D i...The development of materials with excellent microwave absorption(MWA)and electromagnetic interference(EMI)shielding performances has currently received attention.Herein,mesophase pitch-based carbon foam(MPCF)with 3D interconnected pore structure was prepared through the high pressure pyrolysis of mesophase coal tar pitch.It is found that the 3D interconnected cellular pores of MPCF facilitate multiple reflections of electromagnetic waves,which results in the minimum reflection loss(RLmin)value of MPCF reaches-37.84 dB with the effective absorption bandwidth(EAB)of 5.44 GHz at a thickness of 2.70 mm,and the total average electromagnetic shielding effectiveness(SE_(T))under 3.00 mm thickness achieves 26.52 dB in X-band.Subsequently,MPCF is activated by KOH to obtain activated carbon foam(A-MPCF).The average SE_(T)of A-MPCF achieves 103.00 dB for abundant nanopores on the pore cell walls,which leads to a transition from the multiple reflections of electromagnetic waves on the walls to diffuse reflection.Unfortunately,the reflection coefficient(R)of A-MPCF increases from 0.78 to 0.90.To reduce the R value,Fe_(3)O_(4)/A-MPCF was fabricated via the in situ growth of nano Fe_(3)O_(4)on A-MPCF.Consequently,the R value of Fe_(3)O_(4)/A-MPCF was reduced from 0.90 to 0.74,whereas the MWA performance was only slightly decreased.This work proposes a simple strategy for simultaneously adjusting MWA and EMI shielding performances of materials.展开更多
Chitosan(CS),a natural polymer derived from chitin found in the exoskeletons of crustaceans,has garnered significant interest in the pharmaceutical field due to its unique properties,including biocompatibility and bio...Chitosan(CS),a natural polymer derived from chitin found in the exoskeletons of crustaceans,has garnered significant interest in the pharmaceutical field due to its unique properties,including biocompatibility and biodegradability.In recent years,various studies have reported that CS can affect drug bioavailability,and interestingly,it works as an oral absorption enhancer and inhibitor.This review offers an in-depth analysis of the mechanisms underlying such a phenomenon and supports its application as a pharmaceutical excipient.CS enhances oral drug absorption through various mechanisms,such as interaction with the intestinal mucosa,tight junction modulation,inhibition of efflux transporters,enzyme inhibition,solubility and stability enhancement,and complexation.On the other side,CS exhibits the ability to inhibit the absorption of certain drugs by adsorbing to lipids and sterols,modulating bile acids and gut microbiota,altering drug-cell interaction at the polar interface,and mucus-mediated entrapment and interference.Future potential pharmaceutical research in this field includes elucidating the underneath absorption relevant mechanisms,rational use in formulations as excipient,exploring functional CS derivatives,and developing CS-based drug delivery systems.This comprehensive review highlights CS's versatile and significant role in enhancing and inhibiting oral drug absorption,providing insights into the complexities of drug delivery and the potential of CS to improve therapeutic outcomes.展开更多
Using the pulp of Annona squamosa L.as the raw material,polysaccharides were extracted using ultrasonicassisted hot water extraction,with polysaccharide yield as the response variable.The effects of four factors on ex...Using the pulp of Annona squamosa L.as the raw material,polysaccharides were extracted using ultrasonicassisted hot water extraction,with polysaccharide yield as the response variable.The effects of four factors on extraction efficiency were investigated,and the extraction process was optimized using an orthogonal experimental design.The monosaccharide composition of the polysaccharides was analyzed using ion chromatography(IC).The antioxidant activity was evaluated through DPPH radical scavenging,hydroxyl radical(·OH)scavenging,and ferric reducing antioxidant power(FRAP)assays.Additionally,Franz diffusion cells were used to conduct in vitro transdermal absorption experiments,measuring cumulative permeation and calculating permeation kinetics parameters.The results showed that under optimized extraction conditions,the polysaccharide yield was 50.57%±0.02%.Ion chromatography analysis revealed that the main monosaccharide components were arabinose(0.6%),glucose(40.5%),and fructose(58.9%).Antioxidant evaluation indicated that with the addition of 80μL of the extract,the DPPH radical scavenging rate reached 94.13%±0.81%;with 600μL,the hydroxyl radical scavenging rate was 93.33%±0.92%,and the FRAP value was(38.07±1.30)mmol/L.Transdermal absorption experiments demonstrated that the skin retention rates of the polysaccharide aqueous extract at 75%and 100%concentrations were 4.65%±1.52%and 12.37%±2.14%,respectively,with 12 h cumulative permeation rates of 57.43%±1.08%and 74.24%±0.74%.Kinetic analysis of transdermal absorption showed that the process followed zero-order kinetics,indicating a constant release rate under steady-state conditions,consistent with Fick’s diffusion law.This study systematically combined optimization of polysaccharide aqueous extraction,monosaccharide composition analysis,antioxidant activity evaluation,and transdermal permeation performance analysis.It revealed the bioactive properties and potential applications of Annona squamosa L.polysaccharides,particularly in the fields of antioxidant activity and transdermal permeation.The findings provide essential data to support the development of functional products based on Annona squamosa L.polysaccharides.展开更多
Biochar and biochar composites are versatile materials that can be used in many applications.In this study,biochar was prepared from sawdust and combined with the yttrium iron garnet(YIG)nanocrystal to investigate the...Biochar and biochar composites are versatile materials that can be used in many applications.In this study,biochar was prepared from sawdust and combined with the yttrium iron garnet(YIG)nanocrystal to investigate the shielding effectiveness of the composite structure.Firstly,the effect of the pyrolysis temperature on the shielding effectiveness of biochar was investigated.Secondly,biochars combined with YIG nanocrystals with different contents and shielding effectiveness of the composites were investigated.The electromagnetic effectiveness of the samples was investigated within the X band(8-12 GHz).The findings indicate that biochar demonstrates enhanced absorption properties with elevated pyrolysis temperatures.Biochars demonstrated an approximate 40 d B shielding effectiveness,while YIG exhibited approximately 7 d B,corresponding to absorption at 8 GHz.However,the combination of biochar and YIG exhibited exceptional absorption,reaching 67.12 d B at 8 GHz.展开更多
We present a solid 226 nm deep ultraviolet laser system pumped by a Nd:YAG laser.A diamond Raman laser with a 1485 nm wavelength was generated up to 2.53 mJ pumped by a 9.7 mJ 1064 nm laser,which is the highest pulse ...We present a solid 226 nm deep ultraviolet laser system pumped by a Nd:YAG laser.A diamond Raman laser with a 1485 nm wavelength was generated up to 2.53 mJ pumped by a 9.7 mJ 1064 nm laser,which is the highest pulse energy of a second Stokes diamond Raman laser pumped by a 1064 nm laser as we know.Then,the Raman laser is mixed with the frequency-quadrupled 1064 nm laser to produce the 226 nm laser.The maximum output pulse energy at 226 nm reaches 0.49 mJ.The overall conversion efficiency from1064 to 226 nm is up to 1.14%,which is significantly higher than conventional optical parametric oscillator technology for the generation of 226 nm laser.The 226 nm laser system has been used in a laser-induced fluorescence(LIF)experiment of oxygen two-photon to demonstrate its potential for LIF measurements.展开更多
Aggregation-induced emission luminogens(AIEgens)are typically largeπ-conjugated molecules,but their low affinity and noninvasiveness toward analytes limit practical applications.To address this,smaller,more planar AI...Aggregation-induced emission luminogens(AIEgens)are typically largeπ-conjugated molecules,but their low affinity and noninvasiveness toward analytes limit practical applications.To address this,smaller,more planar AIEgens are needed.Stilbene,though structurally suitable,lacks visible luminescence.Here,we report a minimally modified stilbene-based AIEgen-4-dipropylamino-4'-cyano-bridged stilbene(DpCBS[7])-that exhibits fluorescence solvatochromism and efficient AIE across a broad polarity range in the visible region.DpCBS[7]exhibits low quantum yields(Φ_(fl)=0.010.04)in solvents from nonpolar n-hexane to polar dimethyl sulfoxide,with large Stokes shifts,viscosity-sensitive luminescence,and highly efficient solid-state luminescence(Φ_(fl)=0.70).To elucidate its dual solvatochromic and AiE behavior,femtosecond transient absorption spectroscopy was conducted.In solution,DpCBS[7]displays transient absorption with lifetimes of 21 ps(toluene)and 56 ps(acetonitrile)at 293 K,indicating ultrafast nonradiative decay leading to low Φ_(fl).Arrhenius analysis over the temperature range of 263-313 K revealed activation energies(ΔE_(a))of 9.90kJ/mol in toluene and 12.8 kJ/mol in acetonitrile for the S_(1)→S_(0) decay of DpCBS[7].The ΔE_(a) values show no clear systematic dependence on solvent polarity.In contrast,pre-exponential factor A remains consistently high regardless of solvent polarity,indicating that the striking photophysical response is governed primarily by the pre-exponential factor rather than by modulation of the activation energy.These findings highlight the fundamental importance of tailoring the distribution function through structural modification as a robust strategy to control AiE characteristics.展开更多
The rapid development of electronic devices and communication technologies has resulted in increasingly severe electromagnetic-wave(EW)pollution.Efficient EW absorption(EWA)materials are essential to mitigate their im...The rapid development of electronic devices and communication technologies has resulted in increasingly severe electromagnetic-wave(EW)pollution.Efficient EW absorption(EWA)materials are essential to mitigate their impact and ensure human safety in modern society.Fe-based EWA materials have garnered significant attention owing to their cost-effectiveness,high saturation magnetization,and superior magnetic loss capabilities.This review begins with an introduction to Fe-based EWA materials,followed by a brief description of their EWA mechanisms.Various pristine Fe-based absorbers,such as carbonyl iron powder,ferrite-based materials,Fe-based alloys,Fe-based high-entropy alloys(HEAs),and Fe-based layered ternary transition-metal borides,have been systematically reviewed.Key strategies to enhance the performance of Fe-based composite absorbers,including doping,in-situ oxidation,porous structuring,and composite construction,are critically discussed.Finally,the review presents a summary and future perspectives in this field,highlighting the synergy between Fe-based and high-entropy materials in advancing next-generation EWA for applications in stealth technology,wear-able electronics,and harsh environments.展开更多
UHMWPE(Ultra-High Molecular Weight Polyethylene)plain-weave fabric,characterized by its lightweight and high-strength properties,is widely used in protective equipment such as bulletproof vests and stab-resistant vest...UHMWPE(Ultra-High Molecular Weight Polyethylene)plain-weave fabric,characterized by its lightweight and high-strength properties,is widely used in protective equipment such as bulletproof vests and stab-resistant vests,serving as a key material for enhancing protective performance.This study systematically investigates the influence mechanism of interfacial properties on the energy absorption characteristics of UHMWPE-based protective structures through multi-scale experiments and numerical simulations,and establishes a cross-scale design methodology.Innovatively,an orthotropic constitutive model incorporating dynamic friction coefficients is constructed,combined with a modified Johnson-Cook failure criterion,to achieve high-precision simulation of the entire ballistic impact process(error<3.5%).Additionally,a friction field prediction model considering strain rate effects is developed,and the friction evolution laws of UHMWPE and Para-aramid(Kevlar)fabrics under strain rates of 10^(−3) and 10^(−4) s^(−1) are obtained through MTS pull-out tests.The results show that:(1)there exists a critical yarn-yarn friction coefficient(μ=0.2);exceeding this value leads to a 19%reduction in energy absorption capacity,while viscous interfaces increase the energy dissipation peak by 16%;(2)UHMWPE shows kinetically-dominated absorption(58%)with high rate but high load,increasing damage risk.Para-aramid has friction-dominated absorption(53%)with a lower rate but stable load.Hybrid fabrics use potential-dominated absorption(49%)at a moderate rate,balancing stability and protection.(3)3–5 layers of UHMWPE fabric yield optimal cost-effectiveness,with the unit cost reduction rate of the HS+5U scheme reaching 2.74 m/(s·$),which is 91%higher than that of the hybrid scheme.(4)For HS+5U(5-ply UHMWPE),V50 is 520 m/s,meeting primary protection requirement.For hybrid solutions with U/K≥3(e.g.,HS+6U+2K),V50 reaches 580 m/s(≥540 m/s),satisfying advanced protection requirement.This research provides critical references for the design of flexible protective structures and their engineering applications.展开更多
Construction of electron donor-acceptor(D-A)conjugated system is an established strategy for achieving reverse saturable absorption(RSA)and broadband optical limiting(OL).Nevertheless,organic materials exhibit OL abil...Construction of electron donor-acceptor(D-A)conjugated system is an established strategy for achieving reverse saturable absorption(RSA)and broadband optical limiting(OL).Nevertheless,organic materials exhibit OL ability across the visible to near-infrared-II spectra range remain scarce.Herein,a series of D-A typeπ-conjugated copolymers with ultra-narrow bandgaps(0.62-0.76 e V)and strong ICT absorption were synthesized by coupling electron-withdrawing block[1,2,5]thiadiazolo[3,4-g]quinoxaline(TQ)with various electron-donating groups(thiophene,selenophene,bithiophene,di(thiophen-2-yl)ethene,and thienothiophene for P1-P5,respectively).Z-scan experiments reveal that all copolymers exhibit RSA behaviours at both 532 and 1064 nm,while P1,P3 and P4 maintain RSA performance extending to 1600 nm.Among all copolymers,P5 exhibits the strongest RSA performance upon both 532 and 1064 nm laser pulses,with the highest nonlinear absorption coefficient(β_(eff))of 51.5 and 49.4 cm·GW^(-1),respectively,and the lowest OL onset fluence(Fon)of 0.31 and 0.38 J·cm^(-2),respectively.In contrast,P4 shows optimal RSA property at 1600 nm laser pulse,withβeff of 13.1 cm·GW^(-1)and Fon of 1.43 J·cm^(-2),respectively.Combining the results of Z-scan and UV-Vis-NIR experiments,it can be speculated that moderate ground-state absorption,rather than excessively strong absorption,favors superior RSA properties.This work offers valuable insights for designing copolymers with excellent RSA behavior,as well as presents a class of candidate material systems for ultrabroadband optical limiting.展开更多
Environmental pollution,energy consumption,and greenhouse gas emissions are critical global issues.To address these challenges,optimizing skimmer coatings is a major step in commercializing cleaning oil stains.This re...Environmental pollution,energy consumption,and greenhouse gas emissions are critical global issues.To address these challenges,optimizing skimmer coatings is a major step in commercializing cleaning oil stains.This research presents a novel approach to creating and refining oil absorbent coatings,introducing a unique oil spill removal skimmer enhanced with a super hydrophobic polyaniline(PANI)nanofiber coating.The goal of this study was to improve oil absorption performance,increase the contact angle,lower drag,reduce energy consumption,achieve high desirability,and lower production costs.PANI treated with hydrochloric acid was a key focus as it resulted in higher porosity and smaller pore diameters,providing a larger surface area,which are crucial factors for boosting oil absorption and minimizing drag.To optimize optimal nanofiber morphology,PANI synthesized with methanesulfonic acid was first dedoped and then redoped with hydrochloric acid.After optimization,the most effective skimmer coating was achieved using a formulation consisting of 0.1%PANI,an ammonium persulfate/aniline ratio of 0.4,and an acid/aniline ratio of 9.689,along with redoped PANI nanofibers.The optimized skimmer exhibited a remarkable contact angle of 177.477°.The coating achieved drag reduction of 32%,oil absorption of 88.725%,a cost of$1.710,and a desirability rating of 78.5%.In this study,an optimized skimmer coat containing super hydrophobic coat-PANI nanofibers was fabricated.By enhancing contact angle and reducing drag,these coatings increased the skimmer performance by improving oil absorption and reducing fuel consumption.展开更多
This study explores a novel method for processing cotton stalks—an abundant agricultural byproduct—into long strips that serve as sustainable raw material for engineered bio-based panels.To evaluate the effect of ra...This study explores a novel method for processing cotton stalks—an abundant agricultural byproduct—into long strips that serve as sustainable raw material for engineered bio-based panels.To evaluate the effect of raw material morphology on panel’s performance,two types of cotton stalk-based panels were developed:one using long strips,maintaining fiber continuity,and the other using ground particles,representing conventional processing.A wood strand-based panel made from commercial southern yellow pine strands served as the control.All panels were bonded using phenol-formaldehyde resin and hot-pressed to a target thickness of 12.7 mm and density of 640 kg/m^(3).Their mechanical and physical properties were evaluated through internal bond,bending,thickness swelling,and water absorption tests.Both cotton stalk-based panels showed improved bonding performance compared to the control.The internal bond of the strip-based panel was nearly four times higher than that of the control,while the particlebased panel exceeded it by a factor of two.The strip-based panel showed approximately 15% lower bending stiffness than the wood strand-based panel,yet it surpassed it in load-carrying capacity by 5%.In contrast,the particleboard showed significantly lower bending performance than the strip-based and control panels,despite particle processing being a more conventional method.Both cotton stalk-based panels exhibited higher water absorption and thickness swelling than the wood strand panel.Overall,cotton stalk-based panels—particularly those using strip processing—show promisingmechanical properties,suggesting potential applications in sheathing,furniture,and interior paneling.However,improvements in dimensional stability are needed for broader use.展开更多
基金supported by the National Nature Science Foundation of China(No.11375272)
文摘Elemental calcium plays an important role in human physiology. In order to study the relationship between Ca-intake, Ca-chemical formulation, and Ca-absorptivity, a balance experiment using a ^(41)Ca tracer technique in SD rats was conducted to measure the endogenous fecal calcium and true absorption of calcium. Apparent absorption of calcium was measured as a control to the endogenous calcium labeling experiment. These results show that by using ^(41)Ca labeled endogenous calcium in vivo, researchers could obtain the true calcium absorption data without extrinsic labeling. Therefore, the method was not affected by the chemical structure or type of calcium supplement and might be used in evaluating the absorptivity of marketed calcium supplements.
文摘When the thermal environment is under heated conditions, short-wavelength solar radiation shows a strong influence on the human body and the heat is accumulated in the human body. In order to demonstrate the effect of the short-wavelength solar radiation absorptivity of clothing on physiological temperature in an outdoor space, the relationship between the thermal environment evaluation index, ETFe, and the thermal sensory perceptions of the human body was investigated. A significant temperature difference of 2.7°C was shown for an ETFe that was thermally neutral (neither hot nor cold). The effect of short-wavelength solar radiation absorptivity was strongly apparent in ETFe when direct solar radiation was strong and in warmer outdoor spaces. In an outdoor space where the effect of the sky factor and albedo was strong, the setting of the short-wavelength solar radiation absorptivity was demonstrated to greatly impact the estimation of perceived and physiological temperature. When interviewing subjects on clothing in an outdoor space, it is essential to obtain the hue of clothing.
文摘The mathematical equations of the effective percentage of a complexant and ite complex-ratio with a metal have been developed by means of the β-correction pinciple. From a real absorbance of the chelate produced,its true absorptivity can be determined accurately. The β-correction spectrophotometry was studied for the determinations of the desired parameters above, using the reaction of lead with Eriochrome Black T(EBT) at pll 8.2. The results show that the analytical sensitivity and precision by β-correction method are both mucb higher than those by the single wavelength method, the complex-ratio of Pb(Ⅱ) with EBT equals to 1:4 and the true molar absorptivity of Pb(EBT)4 chelate at 550 nm is 3.52,104 L.mol-1.cm-1.
文摘Choosing two different elements of rare earth, the absorptivity of them on copper and its alloys were researched from the category of rare earth, melting point, adding methods, casting temperature, time of heat preservation, quantity of rare earth additives etc. The laws of affecting the absorptivity are found through the research. The distributing of rare earth, existent state and the formed compounds on copper and its alloys were observed in the casting state. The absorptivities of rare earth on copper and its alloys were analyzed.
基金This work was supported by the National Natural Science Foundation of China(No.50374038,50574040)Specialized Research Fund for the Doctoral Program of Higher Education(20030251002)+1 种基金Key Project of the Ministry of Education(03071)by the Department of Science and Technology Shanghai(045407017).
文摘The molar absorption coefficients of each of 14 kinds of amino acids were determined by the spectrophotometric method, and the mean molar absorption coefficients of 37 different mixtures of each with amino acid composition exactly equivalent to that of the peptide chain of the corresponding lipopeptide were determined based on calculation or experimental. The significance of the results is that the mean molar absorption coefficients strongly demonstrate the regular patterns, though different amino acids bear quite different molar absorption coefficients.
基金This research was funded by National Major Scientific and Technological Special Project for“Significant New Drugs Development”(No.2015ZX09501005)Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(No.2016-I2M-1-012).
文摘Background:Traditional Chinese medicine involves complex ingredients and mixtures of ingredients that often exhibit low bioavailability,and excipients are often lacking to increase the absorption-enhancing effects.This study modified the generation 4 polyamidoamine dendrimer with polyethylene glycol of different molecular weights(5000,2000,1000)to form a series of polyamidoamine-co-polyethylene glycol(PAMAM-co-PEG)as a novel class of oral absorption enhancers.Evodiamine,the major alkaloid found in the traditional Chinese medicine Wu Zhu Yu(Fructus Evodiae),was used as a model drug to verify the absorption-enhancing effects and the safety of this alkaloid.Methods:This study utilized the solubility determination method documented in the Pharmacopoeia of the People’s Republic of China(2015 edition)and the D0 values recommended in the US FDA guidelines to comprehensively evaluate the solubility of evodiamine.The permeability of evodiamine was assessed using the apparent permeability coefficient in experiments based on in vitro cell models.Multiple aspects of the biological safety of PAMAM-co-PEG were explored using the MTT assay,LDH assay,and total protein release of the rat intestinal tract.Moreover,the absorption-enhancing effects of PAMAM-co-PEG at different molecular weights on evodiamine were verified via the use of in vitro cell models and in vivo intestinal loop circulation experiments with rats.Results:Evodiamine exhibited low solubility and permeability and was classified into class IV compounds using the biopharmaceutical classification system.PAMAM-co-PEG 2000 demonstrated improvement in the biosafety and absorption-enhancement effect of evodiamine at a specific concentration.This study showed that 0.05%(w/v)of PAMAM-co-PEG 2000 increased the cumulative penetration of evodiamine via cell transport by 1.32 times,and 0.10%(w/v)of PAMAM-co-PEG 2000 increased the area under curve value of evodiamine by 1.31 times.Conclusion:Evodiamine possesses low solubility and permeability and leads to poor oral bioavailability and a certain degree of cytotoxicity.PAMAM-co-PEG 2000 was found to be a potentially safe and efficient oral absorption enhancer.The results of this study might create a foundation for the development of novel excipients suitable for the complex active ingredients of traditional Chinese medicine.
基金financially supported by the Hainan Province Science and Technology Special Fund(Grant no:ZDYF2024XDNY187).
文摘Background:Excessive use of inorganic trace minerals(ITMs)in swine production leads to high fecal mineral excretion and environmental risks,while most studies on organic trace minerals(OTMs)focus on single elements,with limited data on the synergistic effects and molecular mechanisms of combined OTMs(Fe,Cu,Mn,Zn)in growing-finishing pigs.Methods:This study aimed to investigate the effects of graded levels of micromineral proteinates(combined OTMs)on growth performance,mineral metabolism,and mRNA expression of mineral regulatory proteins.A total of 360 crossbred Duroc×Landrace×Large White pigs(initial body weight 47.1±4.8 kg)were randomly assigned to 6 dietary treatments:basal diet without microminerals(CON),basal diet with ITMs at commercially recommended levels(IT),and basal diets with 15%(OT 15%),25%(OT 25%),35%(OT 35%)commercially recommended levels(CRL)of combined micromineral proteinates.After a 70-day feeding trial,samples were analyzed using ICP-OES,ELISA,and RT-qPCR.Results:Results showed that reduced levels(15-35%CRL)of micromineral proteinates did not significantly affect average daily gain,average daily feed intake,or feed conversion ratio(gain-to-feed ratio)compared to IT(P>0.05),but significantly increased plasma Cu(1.73-1.83μg/mL)and Zn(1.72-1.97μg/mL)concentrations(P<0.05)and elevated activities of Cu/Zn-superoxide dismutase(32.9-35.9 U/L)and manganese superoxide dismutase(20.5-24.1 U/L)compared to CON(P<0.05),with no significant differences from IT(P>0.05).Fecal excretion of Fe,Cu,Mn,and Zn was significantly reduced by 35-50%in OT 15%-OT 35%groups compared to IT(P<0.05).OT 25%group exhibited the highest apparent absorptivity of Fe(38.5%),Cu(27.8%),and Zn(42.4%)(P<0.05),which was associated with significantly regulated mRNA expression of mineral regulatory proteins:upregulated DMT1,FPN1,ZIP4,and MT1A in the duodenum,and modulated HAMP,ATP7B,ZIP14,and ZnT1 in the liver(P<0.05).Conclusion:In conclusion,dietary supplementation with 25%CRL or less of combined micromineral proteinates can fully meet the nutritional needs of growing-finishing pigs,improve mineral absorptivity,and reduce fecal mineral excretion by regulating intestinal and hepatic mineral transport and homeostatic proteins,providing a sustainable alternative to high-dose ITMs.
基金supported by the Natural Science Foundation of Shanxi Province(202203021212205)Shanxi Province Major Science and Technology Special Project‘Jiebang Guashuai’Project(202101120401008)+1 种基金National Natural Science Foundation of China(52371231)Key R&D Program of Shanxi Province(202302040201008).
文摘With the rapid development of modern electronic technology,the demand for high-performance microwave absorption materials has increased dramatically.In order to meet this demand,the electrospinning of FeNiCo/carbon nanofiber(FeNiCo/CNF)composites with excellent microwave absorption properties was developed,and their potential as high frequency microwave absorption materials was evaluated.Experiment showed that FeNiCo/CNFs achieve a minimum reflection loss(RL_(min))of−55.5 dB with a matching thickness of only 1.6 mm.Microstructure analysis and electromagnetic parameter testing showed that the excellent microwave absorbing properties were mainly due to the combined effect of the network structure of carbon nanofibers and the FeNiCo alloy.This interaction promotes multiple reflections and the efficient absorption of microwaves.Computer simulation also showed that the FeNiCo/CNF composites produce an excellent radar cross-section reduction in typical radar operating frequency bands,which validates their potential application in stealth technology.This is a new concept in the development of high-performance microwave absorption materials.
基金Supported by the National Natural Science Foundation of China(62275053,62275256)the National key Research and Development Program of China(2021YFB3701500)+1 种基金the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2023248)the Eastern Talent Plan Youth Project 2022,the Shanghai Key Laboratory of Optical Coatings and Spectral Modulation(23dz2260500).
文摘This study systematically investigated the influence of deposition rate on the structure,broadband opti⁃cal properties(1.0-13.0μm),and stress characteristics of Germanium(Ge)films.Additionally,a method for enhancing the performance of infrared filters based on rate-modulated deposition of Ge films was proposed.The optical absorption of Ge films in the short-wave infrared(SWIR)and long-wave infrared(LWIR)bands can be effectively reduced by modulating the deposition rate.As the deposition rate increases,the Ge films maintain an amorphous structure.The optical constants of the films in the 1.0-2.5μm and 2.5-13.0μm bands were precisely determined using the Cody-Lorentz model and the classical Lorentz oscillator model,respectively.Notably,high⁃er deposition rates result in a gradual increase in the refractive index.The extinction coefficient increases with the deposition rate in the SWIR region,attributed to the widening of the Urbach tail,while it decreases in the LWIR region due to the reduced absorption caused by the Ge-O stretching mode.Additionally,the films exhibit a tensile stress that decreases with increasing deposition rate.Finally,the effectiveness of the proposed fabrication method for an infrared filter with Ge films deposited at an optimized rate was demonstrated through practical examples.This work provides theoretical and technical support for the application of Ge films in high-performance infrared filters.
基金Supported by the National Natural Science Foundation of China(22378181).
文摘The development of materials with excellent microwave absorption(MWA)and electromagnetic interference(EMI)shielding performances has currently received attention.Herein,mesophase pitch-based carbon foam(MPCF)with 3D interconnected pore structure was prepared through the high pressure pyrolysis of mesophase coal tar pitch.It is found that the 3D interconnected cellular pores of MPCF facilitate multiple reflections of electromagnetic waves,which results in the minimum reflection loss(RLmin)value of MPCF reaches-37.84 dB with the effective absorption bandwidth(EAB)of 5.44 GHz at a thickness of 2.70 mm,and the total average electromagnetic shielding effectiveness(SE_(T))under 3.00 mm thickness achieves 26.52 dB in X-band.Subsequently,MPCF is activated by KOH to obtain activated carbon foam(A-MPCF).The average SE_(T)of A-MPCF achieves 103.00 dB for abundant nanopores on the pore cell walls,which leads to a transition from the multiple reflections of electromagnetic waves on the walls to diffuse reflection.Unfortunately,the reflection coefficient(R)of A-MPCF increases from 0.78 to 0.90.To reduce the R value,Fe_(3)O_(4)/A-MPCF was fabricated via the in situ growth of nano Fe_(3)O_(4)on A-MPCF.Consequently,the R value of Fe_(3)O_(4)/A-MPCF was reduced from 0.90 to 0.74,whereas the MWA performance was only slightly decreased.This work proposes a simple strategy for simultaneously adjusting MWA and EMI shielding performances of materials.
基金financially supported by National Key Research and Development Program of China (No.2021YFD1800900)National Natural Science Foundation of China (No.82073790)+2 种基金Special Fund for Youth Team of Southwest University (No.SWUXJLJ202306)Chongqing Science and Technology Commission (Nos.CSTB2022TIAD-LUX0001,CSTB2023NSCQ-JQX0002)Innovation Research 2035 Pilot Plan of Southwest University (No.SWUXDPY22007)。
文摘Chitosan(CS),a natural polymer derived from chitin found in the exoskeletons of crustaceans,has garnered significant interest in the pharmaceutical field due to its unique properties,including biocompatibility and biodegradability.In recent years,various studies have reported that CS can affect drug bioavailability,and interestingly,it works as an oral absorption enhancer and inhibitor.This review offers an in-depth analysis of the mechanisms underlying such a phenomenon and supports its application as a pharmaceutical excipient.CS enhances oral drug absorption through various mechanisms,such as interaction with the intestinal mucosa,tight junction modulation,inhibition of efflux transporters,enzyme inhibition,solubility and stability enhancement,and complexation.On the other side,CS exhibits the ability to inhibit the absorption of certain drugs by adsorbing to lipids and sterols,modulating bile acids and gut microbiota,altering drug-cell interaction at the polar interface,and mucus-mediated entrapment and interference.Future potential pharmaceutical research in this field includes elucidating the underneath absorption relevant mechanisms,rational use in formulations as excipient,exploring functional CS derivatives,and developing CS-based drug delivery systems.This comprehensive review highlights CS's versatile and significant role in enhancing and inhibiting oral drug absorption,providing insights into the complexities of drug delivery and the potential of CS to improve therapeutic outcomes.
文摘Using the pulp of Annona squamosa L.as the raw material,polysaccharides were extracted using ultrasonicassisted hot water extraction,with polysaccharide yield as the response variable.The effects of four factors on extraction efficiency were investigated,and the extraction process was optimized using an orthogonal experimental design.The monosaccharide composition of the polysaccharides was analyzed using ion chromatography(IC).The antioxidant activity was evaluated through DPPH radical scavenging,hydroxyl radical(·OH)scavenging,and ferric reducing antioxidant power(FRAP)assays.Additionally,Franz diffusion cells were used to conduct in vitro transdermal absorption experiments,measuring cumulative permeation and calculating permeation kinetics parameters.The results showed that under optimized extraction conditions,the polysaccharide yield was 50.57%±0.02%.Ion chromatography analysis revealed that the main monosaccharide components were arabinose(0.6%),glucose(40.5%),and fructose(58.9%).Antioxidant evaluation indicated that with the addition of 80μL of the extract,the DPPH radical scavenging rate reached 94.13%±0.81%;with 600μL,the hydroxyl radical scavenging rate was 93.33%±0.92%,and the FRAP value was(38.07±1.30)mmol/L.Transdermal absorption experiments demonstrated that the skin retention rates of the polysaccharide aqueous extract at 75%and 100%concentrations were 4.65%±1.52%and 12.37%±2.14%,respectively,with 12 h cumulative permeation rates of 57.43%±1.08%and 74.24%±0.74%.Kinetic analysis of transdermal absorption showed that the process followed zero-order kinetics,indicating a constant release rate under steady-state conditions,consistent with Fick’s diffusion law.This study systematically combined optimization of polysaccharide aqueous extraction,monosaccharide composition analysis,antioxidant activity evaluation,and transdermal permeation performance analysis.It revealed the bioactive properties and potential applications of Annona squamosa L.polysaccharides,particularly in the fields of antioxidant activity and transdermal permeation.The findings provide essential data to support the development of functional products based on Annona squamosa L.polysaccharides.
基金support provided by the Center for Fabrication and Application of Electronic Materials at Dokuz Eylül University,Türkiye。
文摘Biochar and biochar composites are versatile materials that can be used in many applications.In this study,biochar was prepared from sawdust and combined with the yttrium iron garnet(YIG)nanocrystal to investigate the shielding effectiveness of the composite structure.Firstly,the effect of the pyrolysis temperature on the shielding effectiveness of biochar was investigated.Secondly,biochars combined with YIG nanocrystals with different contents and shielding effectiveness of the composites were investigated.The electromagnetic effectiveness of the samples was investigated within the X band(8-12 GHz).The findings indicate that biochar demonstrates enhanced absorption properties with elevated pyrolysis temperatures.Biochars demonstrated an approximate 40 d B shielding effectiveness,while YIG exhibited approximately 7 d B,corresponding to absorption at 8 GHz.However,the combination of biochar and YIG exhibited exceptional absorption,reaching 67.12 d B at 8 GHz.
基金supported by the National Natural Science Foundation of China(Grant Nos.U2032136 and U2241288)the Shaanxi Fundamental Science Research Project for Mathematics and Physics(Grant No.23JSY012)。
文摘We present a solid 226 nm deep ultraviolet laser system pumped by a Nd:YAG laser.A diamond Raman laser with a 1485 nm wavelength was generated up to 2.53 mJ pumped by a 9.7 mJ 1064 nm laser,which is the highest pulse energy of a second Stokes diamond Raman laser pumped by a 1064 nm laser as we know.Then,the Raman laser is mixed with the frequency-quadrupled 1064 nm laser to produce the 226 nm laser.The maximum output pulse energy at 226 nm reaches 0.49 mJ.The overall conversion efficiency from1064 to 226 nm is up to 1.14%,which is significantly higher than conventional optical parametric oscillator technology for the generation of 226 nm laser.The 226 nm laser system has been used in a laser-induced fluorescence(LIF)experiment of oxygen two-photon to demonstrate its potential for LIF measurements.
基金supported in part by MEXT/JSPS KAK-ENHI grants 23H02036(G.K.)JP23H04631,JP23K26670,JP23H03833,JP24K01471,JP24K01515(K.M.)+8 种基金JP23K01977,JP23K20039,JP25K01678(K.O.)24K08341(S.S.)Toyota Riken Scholar(K.M.)the Yoshida Aca-demic and Educational Promotion Foundation(K.M.)the Environment Research and Technology Development Fund(grant number 3RA-2502)of the Environmental Restoration and Conservation Agency provided by Ministry of the Environment of Japan(K.M.)Kyushu University Platform of Inter-/Transdisciplinary Energy Research(Q-PIT)Module-Research Program(K.M.)Kyushu University Integrated Initiative for Designing Future Society(K.M.)JST SPRING,Grant Number JPMJSP2180(T.T.)Network Joint Research Center for Materials and Devices(20253036)(K.I.)The Creative Research Encouragement Award,School of Materials and Chemical Technology,Institute of Science Tokyo(G.K.)。
文摘Aggregation-induced emission luminogens(AIEgens)are typically largeπ-conjugated molecules,but their low affinity and noninvasiveness toward analytes limit practical applications.To address this,smaller,more planar AIEgens are needed.Stilbene,though structurally suitable,lacks visible luminescence.Here,we report a minimally modified stilbene-based AIEgen-4-dipropylamino-4'-cyano-bridged stilbene(DpCBS[7])-that exhibits fluorescence solvatochromism and efficient AIE across a broad polarity range in the visible region.DpCBS[7]exhibits low quantum yields(Φ_(fl)=0.010.04)in solvents from nonpolar n-hexane to polar dimethyl sulfoxide,with large Stokes shifts,viscosity-sensitive luminescence,and highly efficient solid-state luminescence(Φ_(fl)=0.70).To elucidate its dual solvatochromic and AiE behavior,femtosecond transient absorption spectroscopy was conducted.In solution,DpCBS[7]displays transient absorption with lifetimes of 21 ps(toluene)and 56 ps(acetonitrile)at 293 K,indicating ultrafast nonradiative decay leading to low Φ_(fl).Arrhenius analysis over the temperature range of 263-313 K revealed activation energies(ΔE_(a))of 9.90kJ/mol in toluene and 12.8 kJ/mol in acetonitrile for the S_(1)→S_(0) decay of DpCBS[7].The ΔE_(a) values show no clear systematic dependence on solvent polarity.In contrast,pre-exponential factor A remains consistently high regardless of solvent polarity,indicating that the striking photophysical response is governed primarily by the pre-exponential factor rather than by modulation of the activation energy.These findings highlight the fundamental importance of tailoring the distribution function through structural modification as a robust strategy to control AiE characteristics.
基金support from the National Natural Science Foundation of China (Nos.52377026 and52301192)Taishan Scholars and Young Experts Program of Shandong Province,China (No.tsqn202103057)+2 种基金Natural Science Foundation of Shandong Province,China (Nos.ZR2024ME046 and ZR2024QE313)Natural Science Basic Research Program of Shaanxi,China (No.2025JC-YBMS-396)Postdoctoral Science Foundation of China (No.2024M761554)
文摘The rapid development of electronic devices and communication technologies has resulted in increasingly severe electromagnetic-wave(EW)pollution.Efficient EW absorption(EWA)materials are essential to mitigate their impact and ensure human safety in modern society.Fe-based EWA materials have garnered significant attention owing to their cost-effectiveness,high saturation magnetization,and superior magnetic loss capabilities.This review begins with an introduction to Fe-based EWA materials,followed by a brief description of their EWA mechanisms.Various pristine Fe-based absorbers,such as carbonyl iron powder,ferrite-based materials,Fe-based alloys,Fe-based high-entropy alloys(HEAs),and Fe-based layered ternary transition-metal borides,have been systematically reviewed.Key strategies to enhance the performance of Fe-based composite absorbers,including doping,in-situ oxidation,porous structuring,and composite construction,are critically discussed.Finally,the review presents a summary and future perspectives in this field,highlighting the synergy between Fe-based and high-entropy materials in advancing next-generation EWA for applications in stealth technology,wear-able electronics,and harsh environments.
基金the Postdoctoral Science Foundation Funded Project of China with grant No.2021M701687Introduction and Education Plan for Young Innovative Talents in Colleges and Universities of Shandong Province.
文摘UHMWPE(Ultra-High Molecular Weight Polyethylene)plain-weave fabric,characterized by its lightweight and high-strength properties,is widely used in protective equipment such as bulletproof vests and stab-resistant vests,serving as a key material for enhancing protective performance.This study systematically investigates the influence mechanism of interfacial properties on the energy absorption characteristics of UHMWPE-based protective structures through multi-scale experiments and numerical simulations,and establishes a cross-scale design methodology.Innovatively,an orthotropic constitutive model incorporating dynamic friction coefficients is constructed,combined with a modified Johnson-Cook failure criterion,to achieve high-precision simulation of the entire ballistic impact process(error<3.5%).Additionally,a friction field prediction model considering strain rate effects is developed,and the friction evolution laws of UHMWPE and Para-aramid(Kevlar)fabrics under strain rates of 10^(−3) and 10^(−4) s^(−1) are obtained through MTS pull-out tests.The results show that:(1)there exists a critical yarn-yarn friction coefficient(μ=0.2);exceeding this value leads to a 19%reduction in energy absorption capacity,while viscous interfaces increase the energy dissipation peak by 16%;(2)UHMWPE shows kinetically-dominated absorption(58%)with high rate but high load,increasing damage risk.Para-aramid has friction-dominated absorption(53%)with a lower rate but stable load.Hybrid fabrics use potential-dominated absorption(49%)at a moderate rate,balancing stability and protection.(3)3–5 layers of UHMWPE fabric yield optimal cost-effectiveness,with the unit cost reduction rate of the HS+5U scheme reaching 2.74 m/(s·$),which is 91%higher than that of the hybrid scheme.(4)For HS+5U(5-ply UHMWPE),V50 is 520 m/s,meeting primary protection requirement.For hybrid solutions with U/K≥3(e.g.,HS+6U+2K),V50 reaches 580 m/s(≥540 m/s),satisfying advanced protection requirement.This research provides critical references for the design of flexible protective structures and their engineering applications.
基金supported by the National Natural Science Foundation of China(No.52102013)。
文摘Construction of electron donor-acceptor(D-A)conjugated system is an established strategy for achieving reverse saturable absorption(RSA)and broadband optical limiting(OL).Nevertheless,organic materials exhibit OL ability across the visible to near-infrared-II spectra range remain scarce.Herein,a series of D-A typeπ-conjugated copolymers with ultra-narrow bandgaps(0.62-0.76 e V)and strong ICT absorption were synthesized by coupling electron-withdrawing block[1,2,5]thiadiazolo[3,4-g]quinoxaline(TQ)with various electron-donating groups(thiophene,selenophene,bithiophene,di(thiophen-2-yl)ethene,and thienothiophene for P1-P5,respectively).Z-scan experiments reveal that all copolymers exhibit RSA behaviours at both 532 and 1064 nm,while P1,P3 and P4 maintain RSA performance extending to 1600 nm.Among all copolymers,P5 exhibits the strongest RSA performance upon both 532 and 1064 nm laser pulses,with the highest nonlinear absorption coefficient(β_(eff))of 51.5 and 49.4 cm·GW^(-1),respectively,and the lowest OL onset fluence(Fon)of 0.31 and 0.38 J·cm^(-2),respectively.In contrast,P4 shows optimal RSA property at 1600 nm laser pulse,withβeff of 13.1 cm·GW^(-1)and Fon of 1.43 J·cm^(-2),respectively.Combining the results of Z-scan and UV-Vis-NIR experiments,it can be speculated that moderate ground-state absorption,rather than excessively strong absorption,favors superior RSA properties.This work offers valuable insights for designing copolymers with excellent RSA behavior,as well as presents a class of candidate material systems for ultrabroadband optical limiting.
文摘Environmental pollution,energy consumption,and greenhouse gas emissions are critical global issues.To address these challenges,optimizing skimmer coatings is a major step in commercializing cleaning oil stains.This research presents a novel approach to creating and refining oil absorbent coatings,introducing a unique oil spill removal skimmer enhanced with a super hydrophobic polyaniline(PANI)nanofiber coating.The goal of this study was to improve oil absorption performance,increase the contact angle,lower drag,reduce energy consumption,achieve high desirability,and lower production costs.PANI treated with hydrochloric acid was a key focus as it resulted in higher porosity and smaller pore diameters,providing a larger surface area,which are crucial factors for boosting oil absorption and minimizing drag.To optimize optimal nanofiber morphology,PANI synthesized with methanesulfonic acid was first dedoped and then redoped with hydrochloric acid.After optimization,the most effective skimmer coating was achieved using a formulation consisting of 0.1%PANI,an ammonium persulfate/aniline ratio of 0.4,and an acid/aniline ratio of 9.689,along with redoped PANI nanofibers.The optimized skimmer exhibited a remarkable contact angle of 177.477°.The coating achieved drag reduction of 32%,oil absorption of 88.725%,a cost of$1.710,and a desirability rating of 78.5%.In this study,an optimized skimmer coat containing super hydrophobic coat-PANI nanofibers was fabricated.By enhancing contact angle and reducing drag,these coatings increased the skimmer performance by improving oil absorption and reducing fuel consumption.
基金supported by the intramural research program of the U.S.Department of Agriculture,National Institute of Food and Agriculture,Biobased Economy Through Biobased Products,under Award#2023-68016-40132.
文摘This study explores a novel method for processing cotton stalks—an abundant agricultural byproduct—into long strips that serve as sustainable raw material for engineered bio-based panels.To evaluate the effect of raw material morphology on panel’s performance,two types of cotton stalk-based panels were developed:one using long strips,maintaining fiber continuity,and the other using ground particles,representing conventional processing.A wood strand-based panel made from commercial southern yellow pine strands served as the control.All panels were bonded using phenol-formaldehyde resin and hot-pressed to a target thickness of 12.7 mm and density of 640 kg/m^(3).Their mechanical and physical properties were evaluated through internal bond,bending,thickness swelling,and water absorption tests.Both cotton stalk-based panels showed improved bonding performance compared to the control.The internal bond of the strip-based panel was nearly four times higher than that of the control,while the particlebased panel exceeded it by a factor of two.The strip-based panel showed approximately 15% lower bending stiffness than the wood strand-based panel,yet it surpassed it in load-carrying capacity by 5%.In contrast,the particleboard showed significantly lower bending performance than the strip-based and control panels,despite particle processing being a more conventional method.Both cotton stalk-based panels exhibited higher water absorption and thickness swelling than the wood strand panel.Overall,cotton stalk-based panels—particularly those using strip processing—show promisingmechanical properties,suggesting potential applications in sheathing,furniture,and interior paneling.However,improvements in dimensional stability are needed for broader use.
