Installing internal bulkheads in a composite bucket foundation alters the rotational symmetry characteristic of a single-compartment bucket foundation,consequently influencing the stress distribution within the bucket...Installing internal bulkheads in a composite bucket foundation alters the rotational symmetry characteristic of a single-compartment bucket foundation,consequently influencing the stress distribution within the bucket and surrounding soil.During the seabed penetration of a spudcan from a jack-up wind turbine installation vessel,an angle may form between the spudcan’s axis and the axis of symmetry of the adjacent composite bucket foundation in the horizontal plane.Such a misalignment may affect load distribution and the non-uniform interaction between the foundation,soil,and spudcan,ultimately influencing the foundation’s stability.This study employs physical model tests to ascertain the trends in end resistance during spudcan penetration in sand,the extent of soil disturbance,and the backflow condition.The finite element coupled Eulerian-Lagrangian method is validated and utilized to determine the range of penetration angles that induce alterations in the maximum vertical displacement and tilt rate of the composite bucket foundation in sand.The differential contact stress distribution at the base of the bucket is analyzed,with qualitative criteria for sand backflow provided.Findings demonstrate that the maximum vertical displacement and tilt rate of the composite bucket foundation display a“wave-like”variation with the increasing spudcan penetration angle,peaking when the angle between the spudcan and bulkhead is the smallest.Stress distribution is predominantly concentrated at the base and apex of the bucket,becoming increasingly uneven as the penetration angle deviates from the foundation’s symmetry axis.The maximum stress gradually shifts to the junction of the bulkhead and bucket bottom on the side with the shortest net distance from the spudcan.Considering the in-place stability and stress state of the composite bucket foundation is therefore imperative,and particular attention should be paid to the foundation’s state when the angle between the spudcan and bulkhead is small.展开更多
The utilization of discarded coral debris in cementitious material is a prominent research area for island construction projects.The aim of this study is to explore the use of environment-friendly cement and waste cor...The utilization of discarded coral debris in cementitious material is a prominent research area for island construction projects.The aim of this study is to explore the use of environment-friendly cement and waste coral sand in the preparation of coral mortar,while investigating its performance when exposed to a chloride environment.Three types of low-carbon cements were employed,such as rapid hardening sulphoaluminate(RCSA)cement,high belite sulphoaluminate(HBCSA)cement,and slag sulphoaluminate cement(SSC).The coulomb electric flux,mechanical properties,free chloride content,and mass change of the cement mortar under exposed to 3.5 wt%NaCl solution were examined at various time intervals.X-ray diffraction analysis was conducted to identify the mineral phases present in the mortar samples.The results demonstrate that the flexural and compressive strength of the mortar consistently increase throughout the 360 days chloride exposure period.Incorporating coral sand into SSC-based mortars enhances their compressive strength from day 28 up until day 360.However,it adversely affects the strength of HBCSA-based mortars.The behavior of mortars exposed to a chloride-rich environment is closely associated with the amount of C-S-H gel present within them.SSC generates a significant quantity of C-S-H gel which possesses a large specific surface area capable of absorbing more chloride ions thereby reducing their concentration within the mortar matrix as well as increasing its mass and improving resistance against chloride ion penetration.展开更多
Poor tumor penetration is a significant challenge for using nanoliposomebased chemotherapy for triple-negative breast cancer(TNBC).Recently,a milieu of biological cues downregulating tumor stroma has been associated w...Poor tumor penetration is a significant challenge for using nanoliposomebased chemotherapy for triple-negative breast cancer(TNBC).Recently,a milieu of biological cues downregulating tumor stroma has been associated with biological metal ions,primarily such as Mn2+.Inspired by this,we hypothesized that Mn2+could serve as a functional component in designing an alternative modulator for the tumor stroma microenvironment by reducing its extracellular matrix,further decreasing its stromal density.Herein,we presented a novel extracellular matrix(ECM)depleter within a tumor involving manganese-based mineralization materials that primed inhibition of the extracellular matrix of cancer cells,demonstrating a facile strategy for improving drug penetration,delivery and therapy efficiency of the doxorubicin-loaded liposome nanoparticles(Dox-LNP).As a result,the manganese mimetic mineralization material,manganese phosphate(MnP),demonstrated controlled biodegradation and biocompatibility within tumor microenvironments.The release of Mn^(2+)from MnP within the cell lysosome or tumor microenvironment inhibited TGF-β expression and its downstream profibrotic signaling pathways,thereby reducing the tumor stroma density by suppressing the expression of α-smooth actin(α-SMA)and collagen I(COL-I),and inducing tumor stromal disruption both in vitro and in vivo.The typical nanomedicines,Dox-LNP,were subsequently used to check their penetration.The MnP pretreated tumor could significantly improve tumor penetration and accumulation of Dox-LNP,which demonstrated a significant improvement in the treatment of TNBC.These achievements proposed a successful tumor stromal regulation material involving manganese mineralization for priming tumor stromal depletion in situ by inhibiting the TGF-β and associated proteins,representing an alternative materials strategy to substitute biotechnology for stromal reduction,which may further represent a great potential of nanomedicine-based cancer therapy.展开更多
Distribution of plant roots in a red soil derived from granite was investigated to study the effect of plantroots on intensifying soil penetrability and anti-scouribility by the double-cutting-ring and the undisturbed...Distribution of plant roots in a red soil derived from granite was investigated to study the effect of plantroots on intensifying soil penetrability and anti-scouribility by the double-cutting-ring and the undisturbedsoil-flume methods, respectively. The plant roots system consisting mostly of fibrils, < 1 mm in diameter,was mainly distributed in the upper surface soil 30 cm in depth. It can remarhably increase the penetrabilityand anti-scouribility of the red soil derived from granite. When the root density was > 0.35 root cm-2, theintensifying effect of roots on both the penetrability and the anti-scouribility could be described by exponentequations, △ Ks = 0.0021RD1.4826 (R2 = 0.9313) and △ As = 0.0003RD1.8478 (R2 = O.9619), where △ Ks isthe value of intensified soil penetrability, a As the value of intensified soil anti-scouribility and RD the rootdensity, especially in the top soils within 30 cm in depth where plant roots were conceotrated.展开更多
文摘Installing internal bulkheads in a composite bucket foundation alters the rotational symmetry characteristic of a single-compartment bucket foundation,consequently influencing the stress distribution within the bucket and surrounding soil.During the seabed penetration of a spudcan from a jack-up wind turbine installation vessel,an angle may form between the spudcan’s axis and the axis of symmetry of the adjacent composite bucket foundation in the horizontal plane.Such a misalignment may affect load distribution and the non-uniform interaction between the foundation,soil,and spudcan,ultimately influencing the foundation’s stability.This study employs physical model tests to ascertain the trends in end resistance during spudcan penetration in sand,the extent of soil disturbance,and the backflow condition.The finite element coupled Eulerian-Lagrangian method is validated and utilized to determine the range of penetration angles that induce alterations in the maximum vertical displacement and tilt rate of the composite bucket foundation in sand.The differential contact stress distribution at the base of the bucket is analyzed,with qualitative criteria for sand backflow provided.Findings demonstrate that the maximum vertical displacement and tilt rate of the composite bucket foundation display a“wave-like”variation with the increasing spudcan penetration angle,peaking when the angle between the spudcan and bulkhead is the smallest.Stress distribution is predominantly concentrated at the base and apex of the bucket,becoming increasingly uneven as the penetration angle deviates from the foundation’s symmetry axis.The maximum stress gradually shifts to the junction of the bulkhead and bucket bottom on the side with the shortest net distance from the spudcan.Considering the in-place stability and stress state of the composite bucket foundation is therefore imperative,and particular attention should be paid to the foundation’s state when the angle between the spudcan and bulkhead is small.
基金Funded by the National Natural Science Foundation of China(No.51708290)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘The utilization of discarded coral debris in cementitious material is a prominent research area for island construction projects.The aim of this study is to explore the use of environment-friendly cement and waste coral sand in the preparation of coral mortar,while investigating its performance when exposed to a chloride environment.Three types of low-carbon cements were employed,such as rapid hardening sulphoaluminate(RCSA)cement,high belite sulphoaluminate(HBCSA)cement,and slag sulphoaluminate cement(SSC).The coulomb electric flux,mechanical properties,free chloride content,and mass change of the cement mortar under exposed to 3.5 wt%NaCl solution were examined at various time intervals.X-ray diffraction analysis was conducted to identify the mineral phases present in the mortar samples.The results demonstrate that the flexural and compressive strength of the mortar consistently increase throughout the 360 days chloride exposure period.Incorporating coral sand into SSC-based mortars enhances their compressive strength from day 28 up until day 360.However,it adversely affects the strength of HBCSA-based mortars.The behavior of mortars exposed to a chloride-rich environment is closely associated with the amount of C-S-H gel present within them.SSC generates a significant quantity of C-S-H gel which possesses a large specific surface area capable of absorbing more chloride ions thereby reducing their concentration within the mortar matrix as well as increasing its mass and improving resistance against chloride ion penetration.
基金financially supported by the National Natural Science Foundation of China(Nos.32471400 and 51902289)the key project of the Natural Science Foundation of Zhejiang Province(No.LZ24E020002)+1 种基金the Key Research&Development Program of Zhejiang Province(No.2024C03019,2024C03075,2021C01180,and 2019C04020)the Interdisciplinary Construction Funding of Biomedical Materials in ZSTU.
文摘Poor tumor penetration is a significant challenge for using nanoliposomebased chemotherapy for triple-negative breast cancer(TNBC).Recently,a milieu of biological cues downregulating tumor stroma has been associated with biological metal ions,primarily such as Mn2+.Inspired by this,we hypothesized that Mn2+could serve as a functional component in designing an alternative modulator for the tumor stroma microenvironment by reducing its extracellular matrix,further decreasing its stromal density.Herein,we presented a novel extracellular matrix(ECM)depleter within a tumor involving manganese-based mineralization materials that primed inhibition of the extracellular matrix of cancer cells,demonstrating a facile strategy for improving drug penetration,delivery and therapy efficiency of the doxorubicin-loaded liposome nanoparticles(Dox-LNP).As a result,the manganese mimetic mineralization material,manganese phosphate(MnP),demonstrated controlled biodegradation and biocompatibility within tumor microenvironments.The release of Mn^(2+)from MnP within the cell lysosome or tumor microenvironment inhibited TGF-β expression and its downstream profibrotic signaling pathways,thereby reducing the tumor stroma density by suppressing the expression of α-smooth actin(α-SMA)and collagen I(COL-I),and inducing tumor stromal disruption both in vitro and in vivo.The typical nanomedicines,Dox-LNP,were subsequently used to check their penetration.The MnP pretreated tumor could significantly improve tumor penetration and accumulation of Dox-LNP,which demonstrated a significant improvement in the treatment of TNBC.These achievements proposed a successful tumor stromal regulation material involving manganese mineralization for priming tumor stromal depletion in situ by inhibiting the TGF-β and associated proteins,representing an alternative materials strategy to substitute biotechnology for stromal reduction,which may further represent a great potential of nanomedicine-based cancer therapy.
文摘Distribution of plant roots in a red soil derived from granite was investigated to study the effect of plantroots on intensifying soil penetrability and anti-scouribility by the double-cutting-ring and the undisturbedsoil-flume methods, respectively. The plant roots system consisting mostly of fibrils, < 1 mm in diameter,was mainly distributed in the upper surface soil 30 cm in depth. It can remarhably increase the penetrabilityand anti-scouribility of the red soil derived from granite. When the root density was > 0.35 root cm-2, theintensifying effect of roots on both the penetrability and the anti-scouribility could be described by exponentequations, △ Ks = 0.0021RD1.4826 (R2 = 0.9313) and △ As = 0.0003RD1.8478 (R2 = O.9619), where △ Ks isthe value of intensified soil penetrability, a As the value of intensified soil anti-scouribility and RD the rootdensity, especially in the top soils within 30 cm in depth where plant roots were conceotrated.
