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Mesoscopic fracture damage evolution and fractal damage constitutive model of heat-treated red sandstone under direct tensile impact loadings

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Journal of Rock Mechanics and Geotechnical Engineering 2025年第1期17卷 323-340页

作者： shi liu Yu Jia Yue Zhai Shaoxu Hao School of Mechanics and Construction Engineering Jinan UniversityGuangzhou510632China School of Geology Engineering and Geomatics Chang'an UniversityXi'an710064China

Understanding the mesoscopic tensile fracture damage of rock is the basis of evaluating the deterioration process of mechanical properties of heat-damaged rock. For this, tensile tests of rocks under high-temperature treatment were conducted with a ϕ75 mm split Hopkinson tension bar (SHTB) to investigate the mesoscopic fracture and damage properties of rock. An improved scanning electron microscopy (SEM) experimental method was used to analyze the tensile fracture surfaces of rock samples. Qualitative and quantitative analyses were performed to assess evolution of mesoscopic damage of heat-damaged rock under tensile loading. A constitutive model describing the mesoscopic fractal damage under thermo-mechanical coupling was established. The results showed that the high temperatures significantly reduced the tensile strength and fracture surface roughness of the red sandstone. The three-dimensional (3D) reconstruction of the fracture surface of the samples that experienced tensile failure at 900 °C showed a flat surface. The standard deviation of elevation and slope angle of specimen fracture surface first increased and then decreased with increasing temperature. The threshold for brittle fracture of the heat-damaged red sandstone specimens was 600 °C. Beyond this threshold temperature, local ductile fracture occurred, resulting in plastic deformation of the fracture surface during tensile fracturing. With increase of temperature, the internal meso-structure of samples was strengthened slightly at first and then deteriorated gradually, which was consistent with the change of macroscopic mechanical properties of red sandstone. The mesoscopic characteristics, such as the number, mean side length, maximum area, porosity, and fractal dimension of crack, exhibited an initial decline, followed by a gradual increase. The development of microcracks in samples had significant influence on mesoscopic fractal dimension. The mesoscopic fractal characteristics were used to establis

关键词： High temperature rock mechanics Dynamic direct tension Red sandstone Mesoscopic fracture mechanism Fractal damage constitutive model

The goat pan‑genome reveals patterns of gene loss during domestication

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Journal of Animal Science and Biotechnology 2025年第1期16卷 49-58页

作者： Jiaxin liu Yilong shi Dongxin Mo Lingyun Luo Songsong Xu Fenghua Lv Frontiers Science Center for Molecular Design Breeding(MOE) State Key Laboratory of Animal Biotech BreedingCollege of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

Background Unveiling genetic diversity features and understanding the genetic mechanisms of diverse goat pheno-types are pivotal in facilitating the preservation and utilization of these genetic ***,the total genetic diversity within a species can’t be captured by the reference genome of a single *** pan-genome is a col-lection of all the DNA sequences that occur in a species,and it is expected to capture the total genomic diversity of the specific *** We constructed a goat pan-genome using map-to-pan assemble based on 813 individuals,including 723 domestic goats and 90 samples from their wild relatives,which presented a broad regional and global *** total,146 Mb sequences and 974 genes were identified as absent from the reference genome(ARS1.2;GCF_001704415.2).We identified 3,190 novel single nucleotide polymorphisms(SNPs)using the pan-genome *** novel SNPs could properly reveal the population structure of domestic goats and their wild ***/absence variation(PAV)analysis revealed gene loss and intense negative selection during domestication and *** Our research highlights the importance of the goat pan-genome in capturing the missing genetic *** reveals the changes in genomic architecture during goat domestication and improvement,such as gene *** improves our understanding of the evolutionary and breeding history of goats.

关键词： Domestication Goat Improvement Pan-genome Presence/absence variation

Statistical Research on Megahertz-peaked Spectra Pulsars

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Research in Astronomy and Astrophysics 2025年第1期25卷 116-134页

作者： Hong-Bing Cai Li Chen shi-Dang Li Kai Wang Hang liu JSNU SPBPU Institute of Engineering & SINO RUSSIAN Institute Jiangsu Normal University School of Physics and Electronic Engineering Jiangsu Normal University

Megahertz-peaked spectra(MPS) pulsars are referred as cases whose radio spectra turn over around 100 MHz. We identified 53 MPS pulsars based on the spectral data from the literature, and statistically analyzed the spatial location distribution, the magnetic field-period distribution, peak frequencies, spectral indices, and dispersion measures of these MPS pulsars. We found that there is a strong positive correlation between the dispersion measures and the peak frequencies of MPS pulsars, and negative correlations of the dispersion measures with spectral indices and the ages are also found. Such correlations suggest that the interstellar medium is an important factor that affects observational properties of MPS pulsars.

关键词： (stars:) pulsars: general ISM: general radio continuum: general

4-Nitrophenol at environmentally relevant concentrations mediates reproductive toxicity in Caenorhabditis elegans via metabolic disorders-induced estrogen signaling pathway

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Journal of Environmental Sciences 2025年第1期147卷 244-258页

作者： Jia Wang Jiechen Yin Danhong Peng Xiaoqian Zhang Zhouhong shi Weixi Li Yingchi shi Mingjun Sun Nan Jiang Beijing Cheng Xingchen Meng Ran liu Key Laboratory of Environmental Medicine Engineering Ministry of EducationSchool of Public HealthSoutheast UniversityNanjing 210009China Department of Obstetrics and Gynecology Zhongda HospitalSchool of MedicineSoutheast UniversityNanjing 210009China Department of Obstetrics and Gynecology The Affiliated Suzhou Hospital of Nanjing Medical UniversitySuzhou Municipal HospitalGusu SchoolNanjing Medical UniversitySuzhouJiangsu 215002China

4-Nitrophenol(4-NP),as a toxic and refractory pollutant,has generated significant concern due to its adverse ***,the potential toxic effects andmechanism remained *** this study,the reproduction,development,locomotion and reactive oxygen species(ROS)production of Caenorhabditis elegans were investigated to evaluate the 4-NP *** used metabolomics to assess the potential damage *** role of metabolites in mediating the relationship between 4-NP and phenotypes was examined by correlation and mediation analysis.4-NP(8 ng/L and 8μg/L)caused significant reduction of brood size,ovulation rate,total germ cells numbers,head thrashes and body bends,and an increase in ***,the oosperm numbers in uterus,body length and body width were decreased in 8μg/***,36 differential metabolites were enriched in the significant metabolic pathways,including lysine biosynthesis,β-alanine metabolism,tryptophan metabolism,pentose phosphate pathway,pentose and glucuronate interconversions,amino sugar and nucleotide sugar metabolism,starch and sucrose metabolism,galactose metabolism,propanoate metabolism,glycerolipid metabolism,and estrogen signaling *** mechanism of 4-NP toxicity was that oxidative stress caused by the perturbation of amino acid,which had effects on energy metabolism through disturbing carbohydrate and lipid metabolism,and finally affected the estrogen signaling pathway to exert toxic ***,correlation and mediation analysis showed glycerol-3P,glucosamine-6P,glucosamine-1P,UDP-galactose,L-aspartic acid,and uracilwere potential markers for the reproduction and glucose-1,6P2 for developmental *** results provided insight into the pathways involved in the toxic effects caused by 4-NP and developed potential biomarkers to evaluate 4-NP toxicity.

关键词： 4-Nitrophenol Caenorhabditis elegans Metabolomics Pathway analysis

Post-silking leaf senescence is delayed in low-N-tolerant maize cultivars under low N fertilization

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The Crop Journal 2025年第1期13卷 246-256页

作者： gui Wei Xinglong Wang Yawei Wu Fan liu Tianqiong Lan Qinlin liu Chengcheng Lyu Fanlei Kong Jichao Yuan College of Agronomy Sichuan Agricultural UniversityChengdu 611130SichuanChina Key Laboratory of Crop Ecophysiology and Farming System in Southwest China Ministry of AgricultureChengdu 611130SichuanChina Crop Ecophysiology and Cultivation Key Laboratory of Sichuan Province Chengdu 611130SichuanChina

A four-year field experiment was conducted with two cultivars and four N rate to investigate the spatiotemporal characteristics of leaf senescence in maize after silking and its response to N fertilizer rates on them,as well as to reveal the differences in post-silking chlorophyll degradation between low-N-tolerant *** results showed that the order of leaf senescence after silking in maize was lower leaf>upper leaf>ear leaf,leaf tip>middle>*** N fertilizer down-regulated the expression of ZmCLH2 and ZmPPH in the leaves at 10-30 d after silking,reducing CLH and PPH activities,thereby delaying the leaf *** effects were more prominent in low-N-sensitive cultivar Xianyu 508(XY508)than in low-N-tolerant cultivar Zhenghong 311(ZH311),especially in the lower leaves and leaf *** low N condition,leaf yellowing and chlorophyll degradation occurred later and slower in ZH311 than in *** resulted in a higher post-silking dry matter accumulation and grain yield in ZH311,which may be one of the important physiological bases of low nitrogen tolerant *** research should focus on developing low-N-tolerant maize cultivars with slower leaf senescence near the ear after silking.

关键词： Low-N-tolerant maize variety Nitrogen fertilizer Spatio-temporal characteristics Chlorophyll degradation

Hierarchical porous carbon guided by constructing organic-inorganic interpenetrating polymer networks to facilitate performance of zinc hybrid supercapacitors

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Chinese Chemical Letters 2025年第1期36卷 561-567页

作者： Ting shi Ziyang Song Yaokang Lv Dazhang Zhu Ling Miao Lihua Gan Mingxian liu Shanghai Key Lab of Chemical Assessment and Sustainability School of Chemical Science and EngineeringTongji UniversityShanghai 200092China College of Chemical Engineering Zhejiang University of TechnologyHangzhou 310014China

Customized design of well-defined cathode structures with abundant adsorption sites and rapid diffusion dynamics,holds great promise in filling capacity gap of carbonaceous cathodes towards high-performance Zn-ion hybrid supercapacitors(ZHC).Herein,we fabricate a series of dynamics-oriented hierarchical porous carbons derived from the unique organic-inorganic interpenetrating polymer *** interpenetrating polymer networks are obtained through physically knitting polyferric chloride(PFC)network into the highly crosslinked resorcinol-formaldehyde(RF)*** of covalent bonding,physical interpenetrating force in such RF-PFC networks efficiently relieves the RF skeleton shrinkage upon ***,the in-situ PFC network sacrifices as a structure-directing agent to suppress the macrophase separation,and correspondingly 3D hierarchical porous structure with plentiful ion-diffusion channels(pore volume of 1.35 cm^(3)/g)is generated in the representative HPC_(4) via nanospace occupation and swelling *** removal of Fe fillers leaves behind a large accessible specific surface area of 1550 m^(2)/g for enhanced Zn-ion *** used as the cathode for ZHC,HPC_(4) demonstrates a remarkable electrochemical performance with a specific capacity of 215.1 mAh/g at 0.5 A/g and a high Zn^(2+)ion diffusion coefficient of 11.1×10^(-18)cm^(2)/*** ZHC device yields 117.0 Wh/kg energy output at a power density of 272.1 W/kg,coupled with good cycle lifespan(100,000 cycles@10 A/g).This work inspires innovative insights to accelerate Zn diffusion dynamics by structure elaboration towards high-capacity cathode materials.

关键词： Carbonaceous cathode Interpenetrating polymer networks Zinc-ion hybrid supercapacitors Specific capacity Energy/power density

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酚醛纤维在热处理过程中微结构的变化

新型炭材料 2004年第2期19卷 124-128页

作者：刘春玲郭全贵史景利刘朗中国科学院山西煤炭化学研究所炭材料重点实验室山西太原030001

　采用热塑性酚醛树脂经熔融纺丝和酸催化固化获得酚醛纤维。借助比表面积及孔结构测定仪、IR、TG MS和XRD等揭示了酚醛纤维在炭化过程中微结构的发展。研究结果表明:在450℃～900℃的热处理过程中,850℃时BET比表面积达到最大值1040m2... 详细信息

　采用热塑性酚醛树脂经熔融纺丝和酸催化固化获得酚醛纤维。借助比表面积及孔结构测定仪、IR、TG MS和XRD等揭示了酚醛纤维在炭化过程中微结构的发展。研究结果表明:在450℃～900℃的热处理过程中,850℃时BET比表面积达到最大值1040m2/g;同时,伴随大量分解气的逸出,炭基体内部形成孔道。

关键词：酚醛纤维热处理过程微结构结构变化酚醛树脂基炭纤维

Heterochronic gastric adenosquamous carcinoma combined with colonic adenoma:A case report

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World Journal of Gastrointestinal Oncology 2025年第3期17卷 418-423页

作者： gui-Jiang liu Xiao-Yi Long Fei Zhang Tao Ren Xun Xia Department of Neurosurgery Clinical Medical College and the First Affiliated Hospital of Chengdu Medical CollegeChengdu 610500Sichuan ProvinceChina Department of Pathology Clinical Medical College and the First Affiliated Hospital of Chengdu Medical CollegeChengdu 610500Sichuan ProvinceChina Department of Oncology The First Affiliated Hospital of Chengdu Medical CollegeChengdu 610500Sichuan ProvinceChina

BACKGROUND Metachronous gastric cancer usually refers to a tumor that occurs in the stomach more than half a year after esophageal cancer surgery,and metastasis of primary esophageal cancer should be *** are few reports of metachronous gastric adenosquamous carcinoma with signet ring cell carcinoma combined with early tubular adenoma of the colon after esophageal cancer surgery,which has a high degree of *** is also the reason for the poor treatment *** SUMMARY A 54-year-old male patient was admitted to the hospital with“dysphagia obstruction”.Seven years ago,the patient was diagnosed with well-differentiated squamous cell carcinoma in the middle esophagus(T4N1M0 stage)and left gastric lymph node *** the final resection of the esophageal cancer,no residual cancer tissue was found in the esophageal and gastric *** patient’s medical history 7 years ago(preoperative gastroscopy and other examinations)revealed no gastric *** with the patient’s history,the diagnosis of recurrent esophageal cancer was made on this *** final pathological results were surprising:Metachronous gastric adenosquamous carcinoma with signet ring cell carcinoma combined with early tubular adenoma of the *** the high malignancy of the tumor,the complexity of the second operation,and many complications,the patient received *** He had a history of esophageal cancer *** should be performed simultaneously to avoid missed diagnosis and misdiagnosis.

关键词： Heterochronic tumor Gastric adenosquamous carcinoma Colonic adenoma Esophageal cancer Signet ring cell carcinoma Case report

Flexible molecules dedicate to release strain of inverted inorganic perovskite solar cell

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Journal of Energy Chemistry 2025年第1期100卷 87-93页

作者： Hongrui Sun Sanlong Wang Pengyang Wang Yali liu Shanshan Qi Biao shi Ying Zhao Xiaodan Zhang Institute of Photoelectronic Thin Film Devices and Technology Renewable Energy Conversion and Storage CenterState Key Laboratory of Photovoltaic Materials and CellsNankai UniversityTianjin 300350China Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin Tianjin 300350China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Engineering Research Center of Thin Film Photoelectronic Technology of Ministry of Education Tianjin 300350China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China

The tensile strain in inorganic perovskite films induced by thermal annealing is one of the primary factors contributing to the inefficiency and instability of inorganic perovskite solar cells(IPSCs),which reduces the defect formation ***,a flexible molecule 5-maleimidovaleric acid(5-MVA)was introduced as a strain buffer to release the residual strain of CsPbI_(2.85)Br_(0.15)*** anhydride and carboxyl groups in 5-MVA interact strongly with the uncoordinated Pb^(2+)through Lewis acid-base reaction,thus tightly“pull”the perovskite *** in-between soft carbon chain increased the structural flexibility of CsPbI_(2.85)Br_(0.15)perovskite materials,which effectively relieved the intrinsic internal strain of CsPbI_(2.85)Br_(0.15),resisted the corrosion of external strain,and also reduced the formation of defects such as VIand *** addition,the introduction of 5-MVA improved crystal quality,passivated residual defects,and narrowed energy level ***,power conversion efficiency(PCE)of NiOxbased inverted IPSCs increased from 19.25%to 20.82%with the open-circuit voltage enhanced from 1.164 V to 1.230 *** release of strain also improved the stability of CsPbI_(2.85)Br_(0.15)perovskite films and devices.

关键词： Inverted inorganic perovskite solar cells Flexible molecules Strain release Crystallization Energy barrier High PCE