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A microscopically assisted limited colectomy mouse model of early colon cancer 认领 引用
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作者 Yu Han Yixin Zhang +1 位作者 Dazhi Gao Xuefeng Zhao 《Animal Models and Experimental Medicine》 CAS CSCD 2026年第5期879-885,共7页
Background:Currently,there is a lack of an adequate rodent model for investigating sur-gical techniques and comprehensive treatment options for patients with colorectal can-cer(CRC).This study presents a mouse model t... Background:Currently,there is a lack of an adequate rodent model for investigating sur-gical techniques and comprehensive treatment options for patients with colorectal can-cer(CRC).This study presents a mouse model that involves the orthotopic implantation of colon cancer,followed by a limited colectomy,with the aim of addressing this issue.Methods:To establish an early colon tumor model,luciferase-tagged CT-26 cells were implanted into the ascending colon wall of BALB/c mice.After a 1-week observation period,a limited colectomy procedure was performed.The progression of cancer and the impact of resection were monitored using bioluminescence imaging.Additionally,both short-term and long-term effects of surgical intervention were assessed.Results:The study demonstrated a 100%success rate(40/40)in establishing the BALB/c mouse model of early colon cancer.The technical success rate of limited colec-tomy was also 100%,with no instances of early mortality or morbidity.After the limited colectomy procedure,none of the animals exhibited any primary tumors,bloody ascites,recurrence or local invasion,intestinal obstruction,lymph node metastasis,peritoneal seeding,or anastomotic leakage.Furthermore,there were no reported deaths during the postresection observation period in animals treated with limited colectomy.Conclusion:In summary,our research group has successfully described a novel and reproducible surgical resection model for colon cancer in mice,which reflects the clinical scenario. 展开更多
关键词 BALB/c mouse early colon cancer microscopically assisted limited colectomy orthotopic model surgery model
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Scanning Electron Microscopically Study of Sesame Seeds Infected with Macrophomina phaseolina 认领 引用
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作者 D. A. El-Wakil A. M. Mahdy R. Z. El-Menshawy 《Journal of Agricultural Science and Technology(A)》 2011年第1X期96-99,共4页
The direct impact of seed-borne fungi on seed is considerable. Many fungi are serious parasites of seed primordial and maturing seeds and reduce yield of seed both quantitatively and qualitatively. Other fungi, includ... The direct impact of seed-borne fungi on seed is considerable. Many fungi are serious parasites of seed primordial and maturing seeds and reduce yield of seed both quantitatively and qualitatively. Other fungi, including saprophytes and very weak parasites, may lower the quality of seeds by causing discoloration which may seriously depreciate the commercial value of seeds, particularly of grain when graded for consumption. Studies by using scanning electron microscopy （SEM） confirmed the importance of the seed coat, and seed cells as infection sites as well as location of the mycelium of the investigated fungus. Macrophominaphaseolina The present investigation is undertaken to study the colonization, infection and fungal establishment on different sesame seed parts by （SEM）. A successful colonization of M. phaseolina to seed tissues was also detected. Different forms of pycnidial shapes were also observed. 展开更多
关键词 Scanning electron microscope Macrophomina phaseolina sesame seed
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Probing high-order deformation effects in neutron-deficient nuclei246,248No with improved potential-energy-surface calculations 认领 引用 被引量：1
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作者 Jin-Liang Guo Hua-Lei Wang +2 位作者 Kui Xiao Zhen-Zhen Zhang Min-Liang Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第3期143-152,共10页
The high-order deformation effects in even-even246,248No are investigated by means of pairing self-consistent WoodsSaxon-Strutinsky calculations using the potential-energy-surface(PES)approach in an extended deform... The high-order deformation effects in even-even246,248No are investigated by means of pairing self-consistent WoodsSaxon-Strutinsky calculations using the potential-energy-surface(PES)approach in an extended deformation space(β2,β3,β4,β5,β6,β7,β8).Based on the calculated two-dimensional projected energy maps and different potential energy curves,we found that the highly even-order deformations have an important impact on both the fission trajectory and energy minima,while the odd-order deformations,accompanying the even-order ones,primarily affect the fission path beyond the second barrier.Relative to the light actinide nuclei,the nuclear ground state changes to the superdeformed configuration,but the normally deformed minimum,as the low-energy shape isomer,may still be primarily responsible for enhancing nuclear stability and ensuring experimental accessibility in246,248No.Our present investigation indicates the nonnegligible impact of high-order deformation effects along the fission valley and will be helpful for deepening the understanding of different deformation effects and deformation couplings in nuclei,especially in this neutron-deficient heavy-mass region. 展开更多
关键词 High-order deformations Neutron-deficient nuclei Potential energy surface Nuclear stability Macroscopic–microscopic model
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Mechanistic insights into the strength and slaking resistance enhancement of biocemented sand through xanthan gum-assisted CaCO3 nucleation 认领 引用
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作者 Sai ZHANG Jianwen DING +2 位作者 Shoujie WANG Kexiang ZHANG Xinrui ZHANG 《ENGINEERING Structure and Civil Engineering》 SCIE EI CAS CSCD 2026年第4期674-689,共16页
To address the limited reinforcement efficiency of enzyme-induced calcium carbonate precipitation(EICP)caused by insufficient nucleation sites,this study introduces xanthan gum(XG)to immobilize the enzyme and promote ... To address the limited reinforcement efficiency of enzyme-induced calcium carbonate precipitation(EICP)caused by insufficient nucleation sites,this study introduces xanthan gum(XG)to immobilize the enzyme and promote the CaCO3 nucleation.A series of unconfined compressive strength(UCS)tests and ultrasonic oscillation tests were conducted to evaluate the effects of XG on the mechanical behavior and slaking resistance of biocemented sand.The nucleation and cementation mechanisms of XG addition were clarified through scanning electron microscopy with energy-dispersive spectroscopy and X-ray diffraction.The results demonstrate that as the XG concentration increased from 0 to 2 g/L,the UCS increases from 121.10 to 231.05 kPa,showing an increase of 90.8%.At the same time,the average slaking index decreases from 2.588 to 1.323.The enhancement is attributed to the increased viscosity of the enzyme solution with XG addition,which improves solution retention in low-energy sites.In addition,the negatively charged carboxylate groups on XG enhance Ca2+adsorption,creating more nucleation sites and promoting targeted precipitation of CaCO3 at particle contact points and interfaces.This study confirms that biopolymer-assisted nucleation can improve both the strength and slaking resistance of biocemented sand,providing a basis for promoting biocementation technologies in applications such as erosion control and hydrological engineering. 展开更多
关键词 EICP XG strength slaking resistance microscopic mechanism
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Revisiting the self-sealing behavior of compacted bentonite in an annular technological void 认领 引用
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作者 Xusheng Yan Qiong Wang +2 位作者 Weimin Ye Fengshou Zhang Jingli Xie 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2026年第4期2980-2994,共15页
The self-sealing capacity of compacted bentonite governs the effectiveness of engineering barriers constructed in deep geological repositories(DGRs)for high-level radioactive wastes.This research aims to elucidate ben... The self-sealing capacity of compacted bentonite governs the effectiveness of engineering barriers constructed in deep geological repositories(DGRs)for high-level radioactive wastes.This research aims to elucidate bentonite’s self-sealing behavior when exposed to an annular technological void using visualization tests.Water infiltration initiated self-sealing behavior,induced cracking phenomena,and caused color changes on the bentonite surface.These cracks interfered with the self-sealing behaviors and resulted in a suboptimal sealing state.The color difference index was used to track the transition from a cracking state to microstructural reconstruction,revealing water migration pathways and hydration levels.The results confirm the temporal and spatial dependencies of color changes and pore structure evolution during self-sealing.Initially,bentonite exhibited a free swelling pattern,which gradually transitioned to a constant volume pattern as the sealing progressed.The gradual closure of the cracks is attributed to the compression from the swelled parts and the clogging effect of newly formed sealing materials within the water-filled cracks.This study provides a comprehensive understanding of the self-sealing behavior of compacted bentonite,which is essential for optimizing multi-barrier system designs and mitigating geological environmental risks in DGRs. 展开更多
关键词 Compacted bentonite Technological void Self-sealing Microscopic structure Color space Sealing mechanism
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Composite low-carbon biopolymer-amended bentonite in geosynthetic clay liners for containing acid mine drainage leachate 认领 引用
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作者 Heng Zhuang Yingzhen Li +2 位作者 Kuo Tian Xianlei Fu Yanjun Du 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2026年第3期2366-2378,共13页
Acid mine drainage(AMD)leachate is a global pollutant issue that impacts groundwater environment quality.This study investigated the feasibility of a composite biopolymer-amended bentonite as a geosynthetic clay liner... Acid mine drainage(AMD)leachate is a global pollutant issue that impacts groundwater environment quality.This study investigated the feasibility of a composite biopolymer-amended bentonite as a geosynthetic clay liner core material to contain AMD leachate.The real AMD leachate with a pH of 3.1,sourced from an acidic pyrite tailings site,was employed as a specific test leachate used in this study.The composite biopolymer was composed of welan gum(WG)and xanthan gum(XG)at different dry weight-based ratios.Modified fluid loss(MFL)tests were conducted to evaluate hydraulic conductivity(k)of bentonites to optimize WG:XG ratio.Rheological properties of biopolymer solutions were measured,serving as indicative parameters of biopolymer elution.The results indicated biopolymer-amended bentonites with the WG:XG ratio of 8:2 possessed lowest k(1.5×10−11m/s to 7.2×10−11m/s),lower than unamended bentonite(1.2×10−10m/s to 8.6×10−10m/s)in the AMD leachate condition.In addition,biopolymer solutions with WG:XG ratio of 8:2 exhibited highest viscosity.Thermogravimetric analysis,ultraviolet–visible spectroscopy,and Fourier transform infrared spectroscopy were conducted on the composite biopolymer,revealing that WG and XG interacted via physical cross-linking.Additionally,scanning electron microscopy and atomic force microscopy images indicated that a physical cross-linking and dense network structure conformation was developed in the composite biopolymer hydrogel at the WG:XG ratio of 8:2.The results demonstrate that the composite biopolymer is a promising low-carbon amendment material for enhancing containment performance of bentonite used in geosynthetic clay liners to contain AMD leachate. 展开更多
关键词 Acid mine drainage Bentonite Biopolymer Hydraulic conductivity Microscopic properties
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Dynamic evolution of residual oil during long-term waterflooding in Middle East carbonate reservoirs:A pore-scale investigation 认领 引用
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作者 Kai-Jun Tong Yue Pan +5 位作者 Sheng Guo Xiao-Cong Lyu Han Chen Hui-Qing Liu Zhi-Xue Sun Jia-Wei Tang 《Petroleum Science》 SCIE EI CAS CSCD 2026年第3期1428-1444,共17页
Long-term water flooding(LTWF)is an efficient way to improve oil recovery(EOR)in carbonate reservoirs in the Middle East.Due to the complex depositional environment and intricate pore-throat structures of carbonate re... Long-term water flooding(LTWF)is an efficient way to improve oil recovery(EOR)in carbonate reservoirs in the Middle East.Due to the complex depositional environment and intricate pore-throat structures of carbonate reservoirs,the development characteristics differ significantly from those of conventional sandstone reservoirs.While the mechanisms of LTWF in carbonate reservoirs are well-documented,there remains a significant gap in understanding the microscopic pore-scale displacement characteristics and the dynamic evolution of residual oil.To address this,nuclear magnetic resonance(NMR)and computed tomography(CT)scanning techniques were employed to investigate the behavior of LTWF across various carbonate rock samples.Initially,NMR technology was utilized to elucidate the pore-throat displacement characteristics at the microscopic level for different core samples under LTWF.Subsequently,CT scanning was applied to explore the dynamic evolution of microscopic residual oil and to categorize the types of residual oil based on their formation mechanisms.We found that LTWF predominantly utilizes oil within microscale pores of 1–10μm and>10μm.As the volumes of injected water increase,there is a noticeable improvement in oil displacement within submicron pores(0.1–1μm).However,residual oil primarily accumulates in nanopores(<0.1μm)and submicron pores.The study identified five distinct types of microscopic residual oil:clustered,throat,droplet,corner adsorbed,and pore lining.Notably,the transformation of residual oil in dolomite cores generally shifts from clustered to throat forms,while in limestone cores,it transitions from clustered to predominantly corner adsorbed and pore lining configurations.This nuanced understanding of oil utilization and residual categories under LTWF offers valuable insights into optimizing EOR strategies in complex carbonate reservoirs. 展开更多
关键词 Long-term water flooding(LTWF) Microscopic pore-throat displacement characteristics Residual oil dynamic evolution Carbonate reservoir
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Revealing the evolution of aerosols in Asian dust events:Insights from their microphysical and elemental characteristics 认领 引用
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作者 Weijie Yao Yuting Zhang +8 位作者 Xiaole Pan Hang Liu Jing Ye Song Lv Sinan Li Yele Sun Jinyuan Xin Hang Su Zifa Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2026年第7期579-588,共10页
Dust particles and their complex interactions with anthropogenic pollutants have caused serious environmental pollution in East Asia.However,there are few observations on the real-time response to the morphological an... Dust particles and their complex interactions with anthropogenic pollutants have caused serious environmental pollution in East Asia.However,there are few observations on the real-time response to the morphological and mixing state changes of individual dust particles.We used a newly developed single-particle optical particle counter(SOPC)for real-time detection of single-particle size and the depolarization ratio(defined as the ratio of the vertical component to the parallel component of backward scattering),combined with an intelligent scanning electron microscope environmental-particle analysis system(IntelliSEM-EPAS),to quantitatively study the evolution process of particle morphology and chemical composition during dust events in March 2023.Fine mode particles dominated the total particle number concentration,with the proportion of sub-1μm particles reaching 90.3%.The depolarization ratio and form factor(single-particle morphology parameters automatically obtained via IntelliSEM-EPAS)of individual fine particles markedly changed(increased from 0.05 to 0.12 and decreased from 0.73 to 0.60,respectively)during the dust events.Further elemental analysis revealed that mixed sulfur-containing particles play a crucial role in the overall morphological changes in fine particles.During the large-scale transmission of dust aerosols,their morphology and mixing state undergo significant changes.Quantitative description of these changes is beneficial for better understanding the uncertainty of the evolution of dust events and model simulations. 展开更多
关键词 Asian dust Single particle Morphology Mixing state Scanning electron microscope
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Microscopic time-dependent mechanical behavior of shale derived from nanoindentation 认领 引用
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作者 Cunbao Li Shilei Zhong +2 位作者 Heping Xie Changtai Zhou Jianjun Hu 《Deep Underground Science and Engineering》 EI CAS CSCD 2026年第1期160-175,共16页
Understanding the microscopic time-dependent mechanical behavior of shale is critical for assessing macroscopic creep and engineering applications.Grid nanoindentation experiments and nanoindentation creep tests were ... Understanding the microscopic time-dependent mechanical behavior of shale is critical for assessing macroscopic creep and engineering applications.Grid nanoindentation experiments and nanoindentation creep tests were systematically conducted to investigate microscopic creep behaviors in shale.The indentation creep displacements and creep rates of the shale's soft,intermediate,and hard phases showed the same evolution patterns.The creep deformation was much higher in the soft phase than in the other two phases.However,the difference in the steady-state creep rates between the three mechanical phases was negligible.A linear relationship was observed between the microscopic contact creep modulus and the microscopic Young's modulus,hardness,creep displacement,and creep rate.The primary mechanism of microscopic creep in shale revealed by the creep strain rate sensitivity parameter was the extension and closure of microcracks.The differences in the microscopic creep parameters derived from the experimental data using the deconvolution methods and representative point methods were evaluated,and the applicability of the two methods was described.The performances of commonly used creep models to predict the microscopic creep behaviors were evaluated.The Burgers model provided the best performance in predicting the steady-state creep deformation and creep rate.The ability of the Mori-Tanaka and Voigt-Reuss-Hill models to derive macroscopic parameters from microscopic mechanical parameters was compared.Both methods provided macroscopic Young's modulus values close to the experimental values;however,neither could predict macroscopic creep parameters based on microscopic creep parameters. 展开更多
关键词 creep models homogenization microscopic creep parameters nanoindentation creep
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Physicochemical Properties,Rheological Behavior and Microstructure of Cold Mix Emulsified Asphalt Modified by Composite Agents 认领 引用
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作者 CAI Yingchun LIU Xiaoge +2 位作者 CHEN Bei YU Xin DING Gongying 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2026年第3期792-804,共13页
To reduce the environmental pollution associated with the construction of asphalt pavements,and to improve the current problems of insufficient stability,durability,and adaptability of cold mix asphalt(CMA),a cold mix... To reduce the environmental pollution associated with the construction of asphalt pavements,and to improve the current problems of insufficient stability,durability,and adaptability of cold mix asphalt(CMA),a cold mix emulsified asphalt(CMEA)was prepared by using emulsified asphalt,silane coupling agent,cement,plaster,and mineral powder.The basic properties of CMEA were evaluated through penetration,softening point,and ductility tests.The high-temperature rheological properties of CMEA were analyzed using dynamic shear rheometry(DSR).The microstructure of CMEA was assessed via fluorescence microscopy(FM)and Fourier transform infrared spectroscopy(FTIR)tests.Results indicate that the emulsion within the emulsified asphalt can be uniformly distributed in the form of particles,resulting in improved storage stability.Compared to the original emulsified asphalt,the addition of cement,plaster,or a combination of both shows better stability and deformation resistance.The CMEA with both the silane coupling agent and cement exhibits the optimal performance.This study provides new insights for the modification and application of CMA. 展开更多
关键词 asphalt pavement cold mix and cold spread emulsified asphalt composite agents dynamic rheological properties microscopic characteristics
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Mitigating acid rain effects on stabilized soils:the role of phosphogypsum in leaching resistance 认领 引用
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作者 Xia Bian Jianyu Xiao +1 位作者 Tao Zhang Lingling Zeng 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2026年第3期2300-2313,共14页
Phosphogypsum,an industrial solid waste,is an effective binder for partially replacing cement in stabilizing dredged sediments.Acid rain,as a worldwide ecological problem,also affects the long-term stability and susta... Phosphogypsum,an industrial solid waste,is an effective binder for partially replacing cement in stabilizing dredged sediments.Acid rain,as a worldwide ecological problem,also affects the long-term stability and sustainability of geotechnical materials and structures.However,the research on leaching effects and long-term durability of phosphogypsum-stabilized soils under acid rain conditions is limited and remains a significant challenge for practical applications.This study investigates the leaching effects and long-term durability of phosphogypsum-stabilized soils by simulating acid rain erosion through semi-dynamic leaching tests.Key parameters,including leached Ca2+concentration,leachate pH,and unconfined compressive strength after leaching,were evaluated.Microscopic analyses with X-ray diffraction(XRD)and scanning electron microscopy(SEM)were also conducted to explore the underlying mechanisms.The results indicate that the presence of phosphogypsum in stabilized soil with high water content shows a significant improvement in leaching resistance subjected to acid ions,evidencing a lower Ca2+concentration and pH value in the leachate,and a higher strength after leaching compared to those samples without phosphogypsum.SEM images and XRD analysis revealed that samples with higher phosphogypsum content possess denser structures due to more needle-shaped ettringite and other minerals in the soil matrix,contributing to improved strength and leaching resistance.The enhanced strength and leaching resistance of phosphogypsum-stabilized soil can be attributed to additional gel formation,a rise in swelling potential,ettringite bridging,and a denser microstructure,which reduces Ca2+availability for leaching in acidic environments. 展开更多
关键词 Leaching Phosphogypsum Stabilized sediment Microscopic characteristics Leaching resistance
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Mesoscopic fracture evolution of granite under different thermal disturbances 认领 引用
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作者 XIE Jin XI Bao-ping +2 位作者 HE Shui-xin DONG Yun-sheng CHEN Lu-hai 《Journal of Central South University》 SCIE EI CAS CSCD 2026年第2期767-782,共16页
Hot-stage polarizing microscopy technique was employed to investigate the mesoscopic fracture evolution characteristics of granite throughout the entire process from room temperature to real-time high temperature and ... Hot-stage polarizing microscopy technique was employed to investigate the mesoscopic fracture evolution characteristics of granite throughout the entire process from room temperature to real-time high temperature and then to cooling.The study analyzed the influence of mineral types,temperature,cooling medium,and the heating and cooling progress on the microcrack development in granite.Additionally,the contributions of heating and cooling to the damage of granite were discussed.The research indicates that crack evolution follows a characteristic trend:the number of small cracks increases,and larger cracks form through the coalescence and propagation of smaller ones during heating.The thermal fracture threshold for granite was identified at 300°C.The three main minerals in granite exhibit distinct area change behaviors with temperature.After natural cooling,mineral areas show a slight increase compared to the pre treatment state.Following thermal shock in water,these areas decrease marginally relative to their extent at 600℃yet remain significantly larger values than initial ones.Thermal shock cooling induces more extensive fracturing in granite compared to natural air cooling.Furthermore,the heating process contributes more significantly to the overall damage than the subsequent cooling stage.This study enhances the understanding of mesoscopic evolution in thermal disturbances treated rocks and provides a theoretical basis for assessing rock stability in high-temperature engineering environments. 展开更多
关键词 granite real-time high temperature thermal shock damage mesoscopic fracture characteristics microscopic observation
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In Situ Transmission Electron Microscopy Study of Titanium-Steel Heterostructure:Real‐Time Analysis of Interfacial Fracture Evolution 认领 引用
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作者 Sheng Zeng Guoqiang You +3 位作者 Lin Deng Yuefeng Ying Cheng Gu Bin Jiang 《Rare Metals》 SCIE EI CAS CSCD 2026年第6期565-578,共14页
Titanium(Ti)-steel composite joints are prone to the formation of compounds such as TiC,TiFe,and TiFe2 during solid‐phase bonding.This phenomenon leads to premature failure and significantly reduces the bonding quali... Titanium(Ti)-steel composite joints are prone to the formation of compounds such as TiC,TiFe,and TiFe2 during solid‐phase bonding.This phenomenon leads to premature failure and significantly reduces the bonding quality of the joints.However,the fracture behavior of the joint influenced by these compounds,particularly on the initiation of cracks,is yet to be elucidated.Therefore,a comprehensive investigation of the fracture behavior of Ti-steel joints is essential for understanding interfacial failure mechanisms.This paper presents the fabrication of a joint between pure titanium TA2 and 45 steel,prepared through solid‐phase diffusion bonding.The original morphology of the bonding interface was characterized using scanning electron microscopy and transmission electron microscopy.Subsequently,the tensile fracture behavior of the interface was observed in real‐time using an in situ tensile stage within the TEM.The results indicate that a continuous TiC reaction layer formed at the interface during bonding,with the phase composition on either side of the interface beingα‐Fe and TiC at the microscopic scale.In situ tensile results revealed that cracks were found to initiate not at theα‐Fe/TiC interface,but approximately 200 nm from the interface on the steel side.This is attributed to the strain localization in the steel region caused by inconsistent deformation between the two phases.This finding provides theoretical guidance for microstructural design and quality optimization of Ti-steel heterostructures. 展开更多
关键词 coincident site lattice model microscopic fracture behavior Ti-steel heterostructure
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Comparative analysis of ductile and brittle fracture modes in high-hardness steel projectiles during impact 认领 引用
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作者 Yilei Yu Minghui Ma +1 位作者 Chengjuan Xie Guangfa Gao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2026年第4期396-409,共14页
This study investigated the impact fragmentation behavior of projectiles with different yield strengths using 45 steel,35CrMnSiA steel,and T12A steel as core materials.Through experimental and simulation analyses,the ... This study investigated the impact fragmentation behavior of projectiles with different yield strengths using 45 steel,35CrMnSiA steel,and T12A steel as core materials.Through experimental and simulation analyses,the fracture mechanisms and damage characteristics of these materials under high strain rate impacts were examined.The results indicated that 45 steel and 35CrMnSiA steel exhibited noticeable ductility,with fracture surfaces showing prominent dimples and shear lips,experiencing significant plastic deformation and necking during impact.In contrast,T12A steel demonstrated brittle behavior,with fracture surfaces characterized by smooth,bright areas and fine radial streaks.In ballistic tests,T12A steel projectiles displayed distinct damage patterns compared to the other two materials due to their brittleness,resulting in shorter residual lengths.The force-time curves obtained from experiments and simulations showed that higher core strength shortened the time to reach peak force and reduced the overall contact duration.However,the high strength of T12A steel was not always associated with higher peak stresses,as its brittle fracture mode led to early instability.Fragment analysis revealed that smaller fragments(<4 mm)primarily originated from the projectile head,while larger fragments came from the tail.Microscopic examination of the fragments revealed a mix of ductile and brittle fracture modes,with different particle sizes exhibiting distinct fracture surface features.Overall,the study provides insights into the impact performance and failure mechanisms of different core materials,highlighting the importance of material properties in determining projectile behavior under high strain rate conditions. 展开更多
关键词 Impact dynamics Fracture mechanics Ductility vs.brittleness Failure modes Scanning electron microscope
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Effects of grain interfacial morphologies on microbially induced calcium carbonate precipitation process:Experimental evidence and numerical analysis 认领 引用
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作者 Hao Liu Chao-Sheng Tang +5 位作者 Chao Lv Xiaohua Pan Zhixiong Zeng Zhengtao Shen Qing Cheng Baojun Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2026年第2期1541-1551,共11页
Microbially induced calcium carbonate precipitation(MICP)is an eco-friendly technology for soil improvement.Although numerous experiments have been conducted to solidify sand foundations using MICP,the mechanisms by w... Microbially induced calcium carbonate precipitation(MICP)is an eco-friendly technology for soil improvement.Although numerous experiments have been conducted to solidify sand foundations using MICP,the mechanisms by which grain interfacial morphologies influencethe MICP process remain unclear.This study utilized 3D-printed flowcells with different boundary morphologies to investigate the effects of interfacial morphologies on the MICP process.CaCO3precipitation characteristics were investigated through microscopic observation and image quantificationanalysis.The results indicate that low flowvelocities near the interface promote bacterial accumulation due to reduced hydrodynamic shear forces.Rough interfaces,compared to smooth ones,enhance bacterial adsorption owing to the larger regions of low flowvelocity,increased surface area,and the formation of local eddies,which promote greater CaCO3precipitation.Compared to the regions away from the interface,a higher abundance of small CaCO3crystals is observed near the interface because of the high urease activity from bacteria and the reduced shear-induced entrainment due to the low flowvelocity.Besides,larger crystals also preferentially precipitate in proximity to interfaces as the low flowvelocity enhances crystal growth according to the particle attachment theory.The presence of rough interfaces further reduces flowvelocities,leading to the precipitation of larger and more densely packed CaCO3crystals.Therefore,rough interfaces promote the microbially induced calcium carbonate precipitation.This work is expected to enhance the understanding of microbially induced calcium carbonate precipitation characteristics on solid surfaces such as soil grains and contribute to the optimization of MICP applications. 展开更多
关键词 Microbially induced calcium carbonate precipitation(MICP) Interfacial morphology Rough surfaces CaCO3distribution Microscopic observation
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Tilted and Twisted Magnetic Moments in the Kitaev Magnet α-RuCl3 认领 引用
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作者 Xiao Wang Fengfeng Zhu +8 位作者 Markus Braden Karin Schmalzl Wolfgang Schmidt Martin Meven Erxi Feng Yinghao Zhu Alexandre Bertin Paul Steffens Yixi Su 《Chinese Physics Letters》 SCIE EI CAS CSCD 2026年第5期161-173,共13页
The layered honeycomb magnetα-RuCl3has attracted intense scrutiny as a prime candidate for realizing the Kitaev quantum spin liquid,yet a consensus on its microscopic Hamiltonian remains elusive due to the materia... The layered honeycomb magnetα-RuCl3has attracted intense scrutiny as a prime candidate for realizing the Kitaev quantum spin liquid,yet a consensus on its microscopic Hamiltonian remains elusive due to the material's extreme sensitivity to structural details.Here,we report a comprehensive reexamination of the low-temperature crystallographic and magnetic structures of high-qualityα-RuCl3single crystals using unpolarized and polarized neutron diffraction.We confirm a sharp,first-order structural phase transition to the rhombohedral R3 space group with a pronounced thermal hysteresis.Crucially,using both spherical and longitudinal neutron polarization analysis,we determine the 3D orientation of the ordered magnetic moment without the ambiguity typically arising from domain distributions.We find that the Ru3+magnetic moments in the zigzag phase are tilted by 15.7°out of the hexagonal plane and,remarkably,exhibit an additional in-plane twist of-13.8°.This“tilted and twistedžgeometry differentiates the ground state from the previously reported models based on unpolarized neutron diffraction or resonant elastic X-ray scattering(REXS)analysis. 展开更多
关键词 kitaev quantum spin liquidyet tilted magnetic moments Kitaev magnet unpolarized polarized neutron diffractionwe microscopic hamiltonian twisted magnetic moments layered honeycomb crystallographic magnetic structures
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Effect of austenitization on martensite transformation in Co-Cr-Mo alloys by in situ observation 认领 引用
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作者 Yan-peng LI Yuan-li XU +2 位作者 Peng PENG Xu-dong ZHANG Zhi-kun MA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2026年第5期1564-1579,共16页
The martensite transformation of Co-Cr-Mo alloys during cooling after holding at different austenitization temperatures(Ta),was investigated via high-temperature confocal laser scanning microscopy(HT-CLSM).The mart... The martensite transformation of Co-Cr-Mo alloys during cooling after holding at different austenitization temperatures(Ta),was investigated via high-temperature confocal laser scanning microscopy(HT-CLSM).The martensite starting temperature(Ms)increases with increasing Ta.Martensite area fraction(fM)firstly decreases,then increases,and finally decreases with increasing Ta.Additionally,inverse martensite transformation,grain growth,and σphase decomposition were examined during heating via differential scanning calorimetry and HT-CLSM.The effects of Ta on martensite transformation and phase composition of the alloys were analyzed.Ms and fM were influenced by both grain size and pre-existing martensite at Ta of 900-950℃,grain size alone at 950-1100℃,and both grain size and elemental diffusion at 1100-1200℃.This study will provide basic theoretical guidance for regulating the microstructure and enhancing the mechanical properties of Co-Cr-Mo alloys. 展开更多
关键词 austenitization temperature Co−Cr−Mo alloys high-temperature confocal laser scanning microscope martensite transformation phase transformation potential barriers
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Observations of high variability in DNA fragmentation of epididymal sperm in men 认领 引用
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作者 Manish Kuchakulla Hriday P.Bhambhvani +3 位作者 Robert Fisch Runzhuo Ma Jonathan Gal Marc Goldstein 《The Canadian Journal of Urology》 SCIE 2026年第2期441-449,共9页
Objectives:Men with obstructive azoospermia(OA)or infertility often require surgical sperm retrieval for assisted reproductive techniques.While sperm can be successfully obtained from either the testis or epididymis i... Objectives:Men with obstructive azoospermia(OA)or infertility often require surgical sperm retrieval for assisted reproductive techniques.While sperm can be successfully obtained from either the testis or epididymis in these patients,sperm DNA integrity may differ between retrieval sites,which could influence reproductive outcomes.This study aimed to determine whether bilateral epididymal and/or testicular sperm extraction is necessary in men with OA or infertility and elevated DNA fragmentation index(DFI).Methods:We retrospectively analyzed men who underwent bilateral testicular biopsy and/or microscopic epididymal sperm aspiration(MESA)by a single surgeon from 2020–2022.TUNEL assays were performed to assess DFI(normal≤15%).The primary endpoint of the study was to evaluate the variability in DFI between the right and left testes/epididymis in men undergoing sperm extraction.Results:In total,24 men met criteria to be included in this analysis who underwent sperm extraction with DFI analysis via MESAand/or testicular biopsy.Among patients with OA,testicular sperm demonstrated significantly lower DFI compared to epididymal sperm on both sides(right testis 9.52 vs.right epididymis 17.61,p=0.01;left testis 9.22 vs.left epididymis 14.71,p=0.04).For each individual patient with OA,the mean intra-patient difference in DFI between right and left epididymal sperm was significantly higher than the mean intra-patient difference in DFI between right and left testicular sperm(12.09%±6.58,compared to 2.27%±1.59,p<0.001,respectively).Conclusion:Bilateral epididymal sperm extraction may be warranted in men with OA given the observed intra-patient variability in DNAfragmentation between epididymides.Conversely,bilateral testicular extraction may be unnecessary,as no significant difference in DNA fragmentation variability was observed between sperm retrieved from either testicle. 展开更多
关键词 DNA fragmentation microscopic epididymal sperm aspiration(MESA) testicular biopsy bilateral sperm extraction male infertility TUNEL
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Study on the strength deterioration characteristics and microscopic mechanisms of moraine soil under freeze-thaw cycles 认领 引用
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作者 Peng-fei Wang Ming-li Li +3 位作者 Ming Chang Jun-lin Jiang Fan Yang Zhi-qiang Zuo 《Journal of Groundwater Science and Engineering》 2026年第1期15-31,共17页
To investigate the strength degradation characteristics and microscopic damage mechanisms of moraine soil under hydro-thermo-mechanical coupling conditions,a series of X-ray Diffraction(XRD),standard triaxial testing,... To investigate the strength degradation characteristics and microscopic damage mechanisms of moraine soil under hydro-thermo-mechanical coupling conditions,a series of X-ray Diffraction(XRD),standard triaxial testing,Scanning Electron Microscopy(SEM),and Nuclear Magnetic Resonance(NMR)experiments were conducted.The mechanical property degradation laws and evolution characteristics of the microscopic pore structure of moraine soil under Freeze-Thaw(F-T)conditions were revealed.After F-T cycles,the stress-strain curves of moraine soil showed a strain-softening trend.In the early stage of F-T cycles(0–5 cycles),the shear strength and elastic modulus exhibited damage rate of approximately 10.33%±0.8%and 16.60%±1.2%,respectively.In the later stage(10–20 cycles),the strength parameters fluctuated slightly and tended to stabilize.The number of F-T cycles was negatively exponentially correlated with cohesion,while showing only slight fluctuation in the internal friction angle,thereby extending the Mohr-Coulomb strength criterion for moraine soil under F-T cycles.The NMR experiments quantitatively characterized the evolution of the internal pore structure of moraine soil under F-T cycles.As the number of F-T cycles increased,fine and micro pores gradually expanded and merged due to the frost-heaving effect during the water-ice phase transition,forming larger pores.The proportion of large and medium pores increased to 59.55%±2.1%(N=20),while that of fine and micro pores decreased to 40.45%±2.1%(N=20).The evolution of pore structure characteristics was essentially completed in the later stage of F-T cycles(10–20 cycles).This study provides a theoretical foundation and technical support for major engineering construction and disaster prevention in the Qinghai-Xizang Plateau. 展开更多
关键词 Moraine soil in the Qinghai-Xizang Plateau F-T cycle Standard triaxial tests soil strength degradation Mohr-Coulomb criterion Microscopic pore structure
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Numerical study on phase difference-driven mechanical behaviors of gravel–structure interface under three-dimensional circular cyclic shear 认领 引用
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作者 Zhenhai WANG Yuke WANG 《ENGINEERING Structure and Civil Engineering》 SCIE EI CAS CSCD 2026年第2期420-439,共20页
Soil-structural interfaces,such as those between foundations,tunnels,retaining walls,and slopes,serve as critical zones for stress and deformation transfer in geotechnical systems.Although extensive research exists on... Soil-structural interfaces,such as those between foundations,tunnels,retaining walls,and slopes,serve as critical zones for stress and deformation transfer in geotechnical systems.Although extensive research exists on two-dimensional interface mechanics,the zonal characteristics,non-coaxial behavior,and reversible volumetric deformation mechanisms under three-dimensional(3D)loading remain poorly understood.To address this gap,a series of discrete element method(DEM)simulations focused on the phase-dependent response of shear stress,normal displacement,and microstructural interactions were conducted in this study.The influence of the tangential displacement phase difference Dpon the 3D cyclic shear behavior of gravel-structure interfaces under circular shear paths was investigated based on DEM.The controlling role of shear path geometry in governing non-coaxial behavior and reversible volumetric deformation is explicitly revealed.Specifically,it is demonstrated that stable,hysteretic stress-displacement loops with minimal volumetric hysteresis are promoted by circular shear paths(Dp=π/2,3π/2),whereas abrupt stress reversals and amplified dilatancy-recompression cycles are induced by bidirectional linear paths(Dp=π,2π).Furthermore,periodic oscillations of non-coaxial angles(α3)are observed,transitioning from 90°under pure rotation to peak fluctuations exceeding 30°under phase-shifted shear.These mechanistic understandings are highlighted as being crucial for the advancement of 3D interface constitutive models. 展开更多
关键词 gravel-structure interface cyclic shear non-coaxial behavior reversible volumetric deformation phase difference microscopic responses
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