Norbornene derivatives exo,endo-2-[2-(3,5-di-tert-butyl-4-hydroxyphenoxy)-acetoxy]methyl-5-norbornene(M1) and 3,3,5,5-tetramethyl-4-piperidinyl 5-norbornene-exo,endo-2-carboxylate(M2)were synthesized and polymerized b...Norbornene derivatives exo,endo-2-[2-(3,5-di-tert-butyl-4-hydroxyphenoxy)-acetoxy]methyl-5-norbornene(M1) and 3,3,5,5-tetramethyl-4-piperidinyl 5-norbornene-exo,endo-2-carboxylate(M2)were synthesized and polymerized by RuCl_2(=CHPh)(PCy_3)_2 to prepare a novel kind of bi-functional polymer bearing sterically hindered phenol(SHP)and hindered amine(HLAS)groups via ring-opening metathesis polymerization(ROMP).The resulting copolymers were characterized by gel permeation chromatography(GPC),~1H-NMR and differen...展开更多
Chinese college students reading in a foreign language seem to read with less understanding and at a considerably slower speed. The factors that hinder Chinese college students' English reading were analyzed at th...Chinese college students reading in a foreign language seem to read with less understanding and at a considerably slower speed. The factors that hinder Chinese college students' English reading were analyzed at the lexical level, the syntactic level,and the discourse level. And then, several reading strategies were recommended to overcome such reading difficulties.展开更多
Copolymerization of propylene and hindered piperidine monomers was carried out over a high activity supported Ziegler-Natta catalyst, using Al(C2H5)(3) as cocatalyst. Factors which affect the copolymerization were stu...Copolymerization of propylene and hindered piperidine monomers was carried out over a high activity supported Ziegler-Natta catalyst, using Al(C2H5)(3) as cocatalyst. Factors which affect the copolymerization were studied, The copolymers exhibited high light stability without adding extra light stabilizers. A self-stabilized polypropylene was prepared.展开更多
Sphingosine-1-phosphate(S1P)is an important lipid mediator that regulates a diverse range of intracellular cell signaling pathways that are relevant to tissue engineering and regenerative medicine.However,the precise ...Sphingosine-1-phosphate(S1P)is an important lipid mediator that regulates a diverse range of intracellular cell signaling pathways that are relevant to tissue engineering and regenerative medicine.However,the precise function of S1P in dental pulp stem cells(DPSCs)and its osteogenic differentiation remains unclear.We here investigated the function of S1P/S1P receptor(S1PR)-mediated cellular signaling in the osteogenic differentiation of DPSCs and clarified the fundamental signaling pathway.Our results showed that S1P-treated DPSCs exhibited a low rate of differentiation toward the osteogenic phenotype in association with a marked reduction in osteogenesis-related gene expression and AKT activation.Of note,both S1PR1/S1PR3 and S1PR2 agonists significantly downregulated the expression of osteogenic genes and suppressed AKT activation,resulting in an attenuated osteogenic capacity of DPSCs.Most importantly,an AKT activator completely abrogated the S1P-mediated downregulation of osteoblastic markers and partially prevented S1P-mediated attenuation effects during osteogenesis.Intriguingly,the pro-inflammatory TNF-αcytokine promoted the infiltration of macrophages toward DPSCs and induced S1P production in both DPSCs and macrophages.Our findings indicate that the elevation of S1P under inflammatory conditions suppresses the osteogenic capacity of the DPSCs responsible for regenerative endodontics.展开更多
In this contribution,we reported the preparation of vitrimers by using commodity thermoplastics via post crosslinking with hindered urea bonds(HUBs).First,three hindered urea diisocyanates(HUDIs)were synthesized via t...In this contribution,we reported the preparation of vitrimers by using commodity thermoplastics via post crosslinking with hindered urea bonds(HUBs).First,three hindered urea diisocyanates(HUDIs)were synthesized via the reactions of N,N'-di-tert-butylethylenediamine,N,N'-diethylethylenediamine,and piperazine with isophorone diisocyanate(IPDI).Thereafter,these HUDIs were used as the crosslinking agents to crosslink poly(hydroxyether of bisphenol A)(PH),a commodity thermoplastics.Fourier transform infrared(FTIR)spectroscopy and dynamic mechanical thermal analyses(DMTA)indicated that the PH thermosets were successfully obtained.It was found that the thermosets displayed the behavior of vitrimers.The PH thermosets can be reprocessed at elevated temperature without using catalyst and the mechanical strengths of vitrimers were recovered as high as 95%.The reprocessing properties are attributable to dynamic exchange reaction of hindered urea bonds,contingent on types of hindered urea bonds.展开更多
The representative azo and anthraquinone dyes containing an insulated hindered piperidinegroup were synthesized.The effect of these pendent groups on lightfastness properties of the dyeswas studied,both in ethyl aceta...The representative azo and anthraquinone dyes containing an insulated hindered piperidinegroup were synthesized.The effect of these pendent groups on lightfastness properties of the dyeswas studied,both in ethyl acetate solution and on cellulose acetate and polyester films.The differ-ent trend of fading rates of azo dyes and anthraquinone dyes in solution and on substrates suggestsdifferent fading mechanisms operating in each case.展开更多
Hindered phenol compound 3,9-bis{1,1-dimethyl-2[β-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl}- 2,4,8,10-tetraoxaspiro[5,5]-undecane (AO-80) is a polymorphous material with different physical structures...Hindered phenol compound 3,9-bis{1,1-dimethyl-2[β-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl}- 2,4,8,10-tetraoxaspiro[5,5]-undecane (AO-80) is a polymorphous material with different physical structures. The initial AO- 80 is highly crystalline, whereas AO-80 obtained by cooling from its molten state is an amorphous material. Annealing treatment below the melting point of AO-80 results in structural development. The mixture of chlorinated polyethylene (CPE) and vitrified AO-80 particles exhibits a dramatic change in the dynamic mechanical properties during heat treatment at 130'C. This change can be attributed to the decomposition of the vitrified AO-80 particles and the hybridization of two constituents. The vitrified AO-80 particles can crystallize again in a CPE matrix by annealing at 100'C, but this crystal is different from that of the initial AO-80 in its microstructure. In addition, the incorporation of CPE chains caused a dramatic increase in the modulus. As a result, the AO-80 crystal particles that contain some CPE chains act as multifunctional cross- links and the CPE/AO-80 hybrid was found to be a new type of elastomer.展开更多
In this study,a series of hindered urea bond(HUB)containing polyurethane-urea methacrylate prepolymers and a none HUB containing polyurethane methacrylate prepolymer were prepared using isobornyl methacrylate as the r...In this study,a series of hindered urea bond(HUB)containing polyurethane-urea methacrylate prepolymers and a none HUB containing polyurethane methacrylate prepolymer were prepared using isobornyl methacrylate as the reactive diluent via one-pot procedure.The prepolymers were characterized fully by various techniques.Then,their thermosets were fabricated via UV curing in presence of a photo initiator,and their mechanical property and thermal behavior were investigated and compared.Different from the none HUB containing thermoset,the HUB containing thermosets(defined as PUT)could be recycled and reprocessed by hot press under relatively mild conditions with high recovery ratio of mechanical property.Furthermore,zinc oxide(ZnO)nanoparticles were modified with 3-(trimethoxysilyl)propyl methacrylate and the modified ZnO(defined as ZnO-TPM)was dispersed and polymerized into PUT matrix to prepare their nanocomposites.The influence of ZnO-TPM on the mechanical performance of the composites was evaluated,which indicated that the Young’s modulus and tensile strength increased gradually to the maximum values at ZnO-TPM content of 1 wt%and then decreased.The composites also displayed good reprocessability with improved recovery ratio compared to the pure PUT sample.In addition,the composite materials exhibited strong UV absorption capacity,implying their potential application in the circumstance where UV-shielding was required.展开更多
Two kinds of liquid distributor, a central discharge or a peripheral discharge, were designed into a hindered fluid- ized bed separator. The beneficiation performance of the fluidized bed was investigated using 0.25-1...Two kinds of liquid distributor, a central discharge or a peripheral discharge, were designed into a hindered fluid- ized bed separator. The beneficiation performance of the fluidized bed was investigated using 0.25-1.00 mm coarse coal slime and the two different distributors. The experimental results show that the heterogeneity of axial particle velocity in the radial direction of the bed can be reduced by a distributor that has a central discharge. The beneficiation performance for this dis- tributor is improved relative to the distributor with the peripheral discharge. This indicates that it is necessary to eliminate or suppress the core-annulus structure within a hindered fluidized bed. Increasing superficial water velocity causes the clean coal ash content, the railings ash content, and the combustible recovery to increase. Additionally, increasing the bed height decreases all of these three indexes. The optimum superficial water velocity and bed height for a 0.25-1.00 mm coal feed were deter- mined to be 3 mm/s and 800 mm, respectively. This work provides a foundation for the scale-up of the bed.展开更多
A series of di-n-hexyl alkyl phosphonates with bulky substituent on phosphorus was synthesized by PTC P-alkylation using crown ether.Upon saponification of the resulting di-n-hexyl alkylphosphonates in the presence of...A series of di-n-hexyl alkyl phosphonates with bulky substituent on phosphorus was synthesized by PTC P-alkylation using crown ether.Upon saponification of the resulting di-n-hexyl alkylphosphonates in the presence of crown ether or quaternary ammonium halide, corresponding mono-hexyl esters of alkyl phosphonic acids were prepared.Ultrasonic wave, as we found, can catalyze the reaction between dialkyl phosphite & metallic sodium and hydrolysis of dihexyl alkyl phosphonates.A series of di-t-alkyl phosphinic acids were synthesized by the reaction of Grignard reagent with PCl_3 followed by oxidation with 30% H_2O_2.It was found that the reaction between dibutyl phosphite and Grignard reagent of t-alkyl chloride is a new synthetic method for the preparation of mono-esters of highly hindered alkyl phosphonic acids.展开更多
Although significant advancements have been achieved in the performance of organic solar cells(OSCs),the intrinsic stability of active layer materials and their morphological instability continue to impede their comme...Although significant advancements have been achieved in the performance of organic solar cells(OSCs),the intrinsic stability of active layer materials and their morphological instability continue to impede their commercial viability.Herein,a strategy of incorporating a hindered phenolic antioxidant AO1010 into polymer donors of pseudo-planar heterojunction(PPHJ)OSCs was put forward to successfully enhance photo-oxidative and morphological stability.AO1010 that features multiple hydroxyl binding sites makes it highly reactive with superoxide radicals,leading to the quenching of radicals and the termination of radical-induced chain degradation reactions,thereby enhancing the intrinsic stability of the material.Besides,due to the excellent thermal stability and significant steric hindrance of AO1010,it can prevent excessive aggregation of donor and acceptor materials,thus improving morphological stability.Moreover,the multiple hydroxyl groups in AO1010 can easily form hydrogen bonds with the fluorine atoms in the renowned donor PM6,enhancing intermolecular interactions.This leads to an increase in crystallinity of PM6,more orderly molecular packing,and improved gradient phase separation morphology,which benefits charge separation and transport.Consequently,compared with the PM6/BTP-eC9 control device,the optimized PPHJ device based on PM6+AO1010/BTP-eC9 achieved a significantly improved PCE of 18.67% with much better stability.Strikingly,AO1010 demonstrates universal applicability for morphology optimization and stability enhancement.When incorporated into the PM6/L8-BO system,it delivered an impressive efficiency of up to 19.03% with excellent stability.This work put forward an effective strategy to improve the morphology and photo-oxidation stability of active layer,paving the way for the accelerated commercialization of OSCs.展开更多
Soil desiccation cracking is a common phenomenon on the earth surface.Numerical modeling is an effective approach to study the desiccation cracking mechanism of soil.This work develops a novel 3D moisture diffusion di...Soil desiccation cracking is a common phenomenon on the earth surface.Numerical modeling is an effective approach to study the desiccation cracking mechanism of soil.This work develops a novel 3D moisture diffusion discrete model that is capable of dynamically assessing the effect of cracking on moisture diffusion and allowing moisture to be discontinuous on both sides of the cracks.Then,the parametric analysis of the moisture exchange coefficient in the 3D moisture diffusion discrete model is carried out for moisture diffusion in continuous media,and the selection criterion of the moisture exchange coefficient for the unbroken cohesive element is given.Subsequently,an example of moisture migration in a medium with one crack is provided to illustrate the crack hindering effect on moisture migration.Finally,combining the 3D moisture diffusion discrete model with the finite-discrete element method(FDEM),the moisture diffusion-fracture coupling model is built to study the desiccation cracking in a strip soil and the crack pattern of a rectangular soil.The evolution of crack area and volume with moisture content is quantitatively analyzed.The modeling number and average width of cracks in the strip soil show a good consistency with the experimental results,and the crack pattern of the rectangular soil matches well with the existing numerical results,validating the coupled moisture diffusion-fracture model.Additionally,the parametric study of soil desiccation cracking is performed.The developed model offers a powerful tool for exploring soil desiccation cracking.展开更多
Rapid diagnosis of rice bacterial diseases is critical for early warning and precise management during their initial phases.The use of rapid nucleic acid detection on paper-based platforms is an innovative technique t...Rapid diagnosis of rice bacterial diseases is critical for early warning and precise management during their initial phases.The use of rapid nucleic acid detection on paper-based platforms is an innovative technique that offers simplicity,portability,and affordability.However,the temperature dependence of the amplification process and variations in paper device technologies hinder on-site detection of pathogens using paper-based platforms.展开更多
基金Sasakawa Scientific Research Grant from the Japan Science Society.
文摘Norbornene derivatives exo,endo-2-[2-(3,5-di-tert-butyl-4-hydroxyphenoxy)-acetoxy]methyl-5-norbornene(M1) and 3,3,5,5-tetramethyl-4-piperidinyl 5-norbornene-exo,endo-2-carboxylate(M2)were synthesized and polymerized by RuCl_2(=CHPh)(PCy_3)_2 to prepare a novel kind of bi-functional polymer bearing sterically hindered phenol(SHP)and hindered amine(HLAS)groups via ring-opening metathesis polymerization(ROMP).The resulting copolymers were characterized by gel permeation chromatography(GPC),~1H-NMR and differen...
文摘Chinese college students reading in a foreign language seem to read with less understanding and at a considerably slower speed. The factors that hinder Chinese college students' English reading were analyzed at the lexical level, the syntactic level,and the discourse level. And then, several reading strategies were recommended to overcome such reading difficulties.
文摘Copolymerization of propylene and hindered piperidine monomers was carried out over a high activity supported Ziegler-Natta catalyst, using Al(C2H5)(3) as cocatalyst. Factors which affect the copolymerization were studied, The copolymers exhibited high light stability without adding extra light stabilizers. A self-stabilized polypropylene was prepared.
基金supported by a National Research Foundation of Korea(NRF)MRC grant(2018R1A5A2020732)by a grant of the Basic Science and Engineering Research Program(2018R1A2B2001867)funded by the Korean government to E.J.C.by the Bio&Medical Technology Development Program(NRF2017M3A9E4047243)funded by the Ministry of Science,ICT and Future Planning,the Republic of Korea to H.R.K.
文摘Sphingosine-1-phosphate(S1P)is an important lipid mediator that regulates a diverse range of intracellular cell signaling pathways that are relevant to tissue engineering and regenerative medicine.However,the precise function of S1P in dental pulp stem cells(DPSCs)and its osteogenic differentiation remains unclear.We here investigated the function of S1P/S1P receptor(S1PR)-mediated cellular signaling in the osteogenic differentiation of DPSCs and clarified the fundamental signaling pathway.Our results showed that S1P-treated DPSCs exhibited a low rate of differentiation toward the osteogenic phenotype in association with a marked reduction in osteogenesis-related gene expression and AKT activation.Of note,both S1PR1/S1PR3 and S1PR2 agonists significantly downregulated the expression of osteogenic genes and suppressed AKT activation,resulting in an attenuated osteogenic capacity of DPSCs.Most importantly,an AKT activator completely abrogated the S1P-mediated downregulation of osteoblastic markers and partially prevented S1P-mediated attenuation effects during osteogenesis.Intriguingly,the pro-inflammatory TNF-αcytokine promoted the infiltration of macrophages toward DPSCs and induced S1P production in both DPSCs and macrophages.Our findings indicate that the elevation of S1P under inflammatory conditions suppresses the osteogenic capacity of the DPSCs responsible for regenerative endodontics.
基金the National Natural Science Foundation of China(Nos.51973113,51133003,and 21774078).
文摘In this contribution,we reported the preparation of vitrimers by using commodity thermoplastics via post crosslinking with hindered urea bonds(HUBs).First,three hindered urea diisocyanates(HUDIs)were synthesized via the reactions of N,N'-di-tert-butylethylenediamine,N,N'-diethylethylenediamine,and piperazine with isophorone diisocyanate(IPDI).Thereafter,these HUDIs were used as the crosslinking agents to crosslink poly(hydroxyether of bisphenol A)(PH),a commodity thermoplastics.Fourier transform infrared(FTIR)spectroscopy and dynamic mechanical thermal analyses(DMTA)indicated that the PH thermosets were successfully obtained.It was found that the thermosets displayed the behavior of vitrimers.The PH thermosets can be reprocessed at elevated temperature without using catalyst and the mechanical strengths of vitrimers were recovered as high as 95%.The reprocessing properties are attributable to dynamic exchange reaction of hindered urea bonds,contingent on types of hindered urea bonds.
文摘The representative azo and anthraquinone dyes containing an insulated hindered piperidinegroup were synthesized.The effect of these pendent groups on lightfastness properties of the dyeswas studied,both in ethyl acetate solution and on cellulose acetate and polyester films.The differ-ent trend of fading rates of azo dyes and anthraquinone dyes in solution and on substrates suggestsdifferent fading mechanisms operating in each case.
基金This work was financially supported by the "The National High Technology Research and Development Program " of theMinistry of Science and Technology of China (the registered number is 2002AA333020).
文摘Hindered phenol compound 3,9-bis{1,1-dimethyl-2[β-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl}- 2,4,8,10-tetraoxaspiro[5,5]-undecane (AO-80) is a polymorphous material with different physical structures. The initial AO- 80 is highly crystalline, whereas AO-80 obtained by cooling from its molten state is an amorphous material. Annealing treatment below the melting point of AO-80 results in structural development. The mixture of chlorinated polyethylene (CPE) and vitrified AO-80 particles exhibits a dramatic change in the dynamic mechanical properties during heat treatment at 130'C. This change can be attributed to the decomposition of the vitrified AO-80 particles and the hybridization of two constituents. The vitrified AO-80 particles can crystallize again in a CPE matrix by annealing at 100'C, but this crystal is different from that of the initial AO-80 in its microstructure. In addition, the incorporation of CPE chains caused a dramatic increase in the modulus. As a result, the AO-80 crystal particles that contain some CPE chains act as multifunctional cross- links and the CPE/AO-80 hybrid was found to be a new type of elastomer.
文摘In this study,a series of hindered urea bond(HUB)containing polyurethane-urea methacrylate prepolymers and a none HUB containing polyurethane methacrylate prepolymer were prepared using isobornyl methacrylate as the reactive diluent via one-pot procedure.The prepolymers were characterized fully by various techniques.Then,their thermosets were fabricated via UV curing in presence of a photo initiator,and their mechanical property and thermal behavior were investigated and compared.Different from the none HUB containing thermoset,the HUB containing thermosets(defined as PUT)could be recycled and reprocessed by hot press under relatively mild conditions with high recovery ratio of mechanical property.Furthermore,zinc oxide(ZnO)nanoparticles were modified with 3-(trimethoxysilyl)propyl methacrylate and the modified ZnO(defined as ZnO-TPM)was dispersed and polymerized into PUT matrix to prepare their nanocomposites.The influence of ZnO-TPM on the mechanical performance of the composites was evaluated,which indicated that the Young’s modulus and tensile strength increased gradually to the maximum values at ZnO-TPM content of 1 wt%and then decreased.The composites also displayed good reprocessability with improved recovery ratio compared to the pure PUT sample.In addition,the composite materials exhibited strong UV absorption capacity,implying their potential application in the circumstance where UV-shielding was required.
文摘Two kinds of liquid distributor, a central discharge or a peripheral discharge, were designed into a hindered fluid- ized bed separator. The beneficiation performance of the fluidized bed was investigated using 0.25-1.00 mm coarse coal slime and the two different distributors. The experimental results show that the heterogeneity of axial particle velocity in the radial direction of the bed can be reduced by a distributor that has a central discharge. The beneficiation performance for this dis- tributor is improved relative to the distributor with the peripheral discharge. This indicates that it is necessary to eliminate or suppress the core-annulus structure within a hindered fluidized bed. Increasing superficial water velocity causes the clean coal ash content, the railings ash content, and the combustible recovery to increase. Additionally, increasing the bed height decreases all of these three indexes. The optimum superficial water velocity and bed height for a 0.25-1.00 mm coal feed were deter- mined to be 3 mm/s and 800 mm, respectively. This work provides a foundation for the scale-up of the bed.
基金Project Supported by National Science Foundation of China.
文摘A series of di-n-hexyl alkyl phosphonates with bulky substituent on phosphorus was synthesized by PTC P-alkylation using crown ether.Upon saponification of the resulting di-n-hexyl alkylphosphonates in the presence of crown ether or quaternary ammonium halide, corresponding mono-hexyl esters of alkyl phosphonic acids were prepared.Ultrasonic wave, as we found, can catalyze the reaction between dialkyl phosphite & metallic sodium and hydrolysis of dihexyl alkyl phosphonates.A series of di-t-alkyl phosphinic acids were synthesized by the reaction of Grignard reagent with PCl_3 followed by oxidation with 30% H_2O_2.It was found that the reaction between dibutyl phosphite and Grignard reagent of t-alkyl chloride is a new synthetic method for the preparation of mono-esters of highly hindered alkyl phosphonic acids.
基金financially supported by the National Natural Science Foundation of China(NSFC)(22479066 and 52333006)Jiangxi Provincial Natural Science Foundation(20212ACB203005 and 20224ACB214002)+1 种基金the Thousand Talents Plan of Jiangxi Province(jxsq2019101051)the financial support from Research Grants Council(RGC)of Hong Kong(General Research Fund No.14303519).
文摘Although significant advancements have been achieved in the performance of organic solar cells(OSCs),the intrinsic stability of active layer materials and their morphological instability continue to impede their commercial viability.Herein,a strategy of incorporating a hindered phenolic antioxidant AO1010 into polymer donors of pseudo-planar heterojunction(PPHJ)OSCs was put forward to successfully enhance photo-oxidative and morphological stability.AO1010 that features multiple hydroxyl binding sites makes it highly reactive with superoxide radicals,leading to the quenching of radicals and the termination of radical-induced chain degradation reactions,thereby enhancing the intrinsic stability of the material.Besides,due to the excellent thermal stability and significant steric hindrance of AO1010,it can prevent excessive aggregation of donor and acceptor materials,thus improving morphological stability.Moreover,the multiple hydroxyl groups in AO1010 can easily form hydrogen bonds with the fluorine atoms in the renowned donor PM6,enhancing intermolecular interactions.This leads to an increase in crystallinity of PM6,more orderly molecular packing,and improved gradient phase separation morphology,which benefits charge separation and transport.Consequently,compared with the PM6/BTP-eC9 control device,the optimized PPHJ device based on PM6+AO1010/BTP-eC9 achieved a significantly improved PCE of 18.67% with much better stability.Strikingly,AO1010 demonstrates universal applicability for morphology optimization and stability enhancement.When incorporated into the PM6/L8-BO system,it delivered an impressive efficiency of up to 19.03% with excellent stability.This work put forward an effective strategy to improve the morphology and photo-oxidation stability of active layer,paving the way for the accelerated commercialization of OSCs.
基金supported by the State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering(Grant No.SKLGDUEK2206)National Natural Science Foundation of China(Grant No.11872340).
文摘Soil desiccation cracking is a common phenomenon on the earth surface.Numerical modeling is an effective approach to study the desiccation cracking mechanism of soil.This work develops a novel 3D moisture diffusion discrete model that is capable of dynamically assessing the effect of cracking on moisture diffusion and allowing moisture to be discontinuous on both sides of the cracks.Then,the parametric analysis of the moisture exchange coefficient in the 3D moisture diffusion discrete model is carried out for moisture diffusion in continuous media,and the selection criterion of the moisture exchange coefficient for the unbroken cohesive element is given.Subsequently,an example of moisture migration in a medium with one crack is provided to illustrate the crack hindering effect on moisture migration.Finally,combining the 3D moisture diffusion discrete model with the finite-discrete element method(FDEM),the moisture diffusion-fracture coupling model is built to study the desiccation cracking in a strip soil and the crack pattern of a rectangular soil.The evolution of crack area and volume with moisture content is quantitatively analyzed.The modeling number and average width of cracks in the strip soil show a good consistency with the experimental results,and the crack pattern of the rectangular soil matches well with the existing numerical results,validating the coupled moisture diffusion-fracture model.Additionally,the parametric study of soil desiccation cracking is performed.The developed model offers a powerful tool for exploring soil desiccation cracking.
基金supported by the National Natural Science Foundation of China(Grant No.32171895)National Key Research and Development Program for Young Scientists,China(Grant No.2022YFD2000200)Jiangsu Province Key Reserch and Development Program Project,China(Grant No.BE2022052-2).
文摘Rapid diagnosis of rice bacterial diseases is critical for early warning and precise management during their initial phases.The use of rapid nucleic acid detection on paper-based platforms is an innovative technique that offers simplicity,portability,and affordability.However,the temperature dependence of the amplification process and variations in paper device technologies hinder on-site detection of pathogens using paper-based platforms.