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Evolution of the elastic properties of lacustrine organic shales under different thermal maturity conditions

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Science China Earth Sciences 2025年第3期68卷 781-802页

作者： Zhenjia CAI Luanxiao ZHAO Jiqiang ma Fengshou ZHANG jianhua GENG State Key Laboratory of marine Geology Tongji University School of Ocean and Earth Science Tongji University Department of Geotechnical Engineering College of Civil Engineering Tongji University

Research on the elastic responses of organic-rich shales during thermal evolution has predominantly focused on North American marine shales. However, the rock physics properties of lacustrine(continental) organic-rich shales with varying maturities, particularly under the unique geological conditions in China, have not yet been comprehensively explored. Therefore,characterizing the elastic properties of lacustrine organic-rich shales across various maturity stages is crucial for understanding their seismic rock physics responses and for enabling the identification of sweet spots in continental shale reservoirs using logging and seismic data, as well as facilitating geophysical monitoring of the in-situ conversion of oil shales. In this study,hydrous pyrolysis experiments were conducted on immature shales from the Chang 7 member of the Yanchang Formation in the Ordos Basin and the Jijuntun Formation in the Fushun Basin. Compressional and shear wave velocities, along with elastic anisotropy, were measured at various stages of thermal maturity to observe the evolution of the elastic properties. For the Chang7 shale(compacted shale), both P-and S-wave velocities perpendicular to the bedding decreased significantly during the oil and gas generation stages, with the S-wave velocity perpendicular to the bedding decreasing by over 40%. Meanwhile, the elastic anisotropy increased significantly, likely because of microcracks formed by hydrocarbon expulsion from the bedding-parallel organic matter. In contrast, the Jijuntun Formation shale(cemented shale) exhibited an increase in both P-and S-wave velocities during the oil generation stage. This trend could be attributed to early-stage cementation, which suppressed microcrack formation, while the increase in the elastic modulus of the organic matter became dominant. However, during the gas generation stage, both velocities decreased, while the anisotropy increased owing to the growth of organic pores and microcracks, which out

关键词： Lacustrine shales Thermal pyrolysis Elastic wave velocity Anisotropy In-situ conversion

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Longitudinal assessment of peripheral organ metabolism and the gut microbiota in an APP/PS1 transgenic mouse model of Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2982-2997页

作者： Hongli Li jianhua huang Di Zhao Lemei Zhu Zheyu Zhang Min Yi Weijun Peng Department of Integrated Traditional Chinese&Western Medicine The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina National Clinical Research Center for Metabolic Diseases ChangshaHunan ProvinceChina Hunan Academy of Chinese Medicine ChangshaHunan ProvinceChina Academician Workstation Changsha Medical UniversityChangshaHunan ProvinceChina

Alzheimer’s disease not only affects the brain,but also induces metabolic dysfunction in peripheral organs and alters the gut *** aim of this study was to investigate systemic changes that occur in Alzheimer’s disease,in particular the association between changes in peripheral organ metabolism,changes in gut microbial composition,and Alzheimer’s disease *** do this,we analyzed peripheral organ metabolism and the gut microbiota in amyloid precursor protein-presenilin 1(APP/PS1)transgenic and control mice at 3,6,9,and 12 months of ***-month-old APP/PS1 mice exhibited cognitive impairment,Alzheimer’s disease-related brain changes,distinctive metabolic disturbances in peripheral organs and fecal samples(as detected by untargeted metabolomics sequencing),and substantial changes in gut microbial composition compared with younger APP/PS1 ***,a strong correlation emerged between the gut microbiota and kidney metabolism in APP/PS1 *** findings suggest that alterations in peripheral organ metabolism and the gut microbiota are closely related to Alzheimer’s disease development,indicating potential new directions for therapeutic strategies.

关键词： Alzheimer’s disease APP/PS1 mice brain-kidney axis gut microbiota heart-brain axis liver-brain axis lung-brain axis microbiota-gut-brain axis peripheral organ metabolism spleen-brain axis

Kaiser Criterion in Factor Models

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Acta mathematica Sinica,English Series 2025年第2期41卷 547-552页

作者： Changhu Wang jianhua Guo Yanyuan ma Shurong Zheng School of mathematical Sciences Peking UniversityBeijing 100871P.R.China School of mathematics and Statistics Beijing Technology and Business UniversityBeijing 100048P.R.China Department of Statistics Pennsylvania State UniversityUniversity ParkPennsylvaniaUSA KLAS and School of mathematics and Statistics Northeast Normal UniversityChangchun 130024P.R.China

Despite of the wide use of the factor models, the issue of determining the number of factors has not been resolved in the statistics literature. An ad hoc approach is to set the number of factors to be the number of eigenvalues of the data correlation matrix that are larger than one, and subsequent statistical analysis proceeds assuming the resulting factor number is correct. In this work, we study the relation between the number of such eigenvalues and the number of factors, and provide the if and only if conditions under which the two numbers are equal. We show that the equality only relies on the properties of the loading matrix of the factor model. Guided by the newly discovered condition, we further reveal how the model error affects the estimation of the number of factors.

关键词： Factor model Kaiser criterion positive definite

Sequence-controlled dynamic covalent units enable decoupling of mechanical and self-healing performance of polymers

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Science China Chemistry 2025年第2期68卷 745-753页

作者： Luzhi Zhang Hongfei huang Lijie Sun Xiaopeng ma Hui Tan Zhengwei You Respiratory Department Shenzhen Children’s Hospital Affiliated to Shantou University Medical CollegeShenzhen 518038China State Key Laboratory for Modification of Chemical Fibers and Polymer materials College of Materials Science and EngineeringInstitute of Functional MaterialsResearch Base of Textile Materials for Flexible Electronics and Biomedical Applications(China Textile Engineering Society)Shanghai Key Laboratory of Lightweight CompositeShanghai Engineering Research Center of Nano-Biomaterials and Regenerative MedicineDonghua UniversityShanghai 201620China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China

Sequence regulation provides an effective approach to controlling the properties of polymer ***,this approach remains an open question in the field of dynamic polymers,which emerge as more and more important new generation ***,we systematically investigate the effect of sequence control of dynamic covalent units in tuning the properties of *** sequence-controlled poly(oxime-urethanes)are *** dynamic oxime-urethane groups are relatively dispersed(SCP-1)or concentrated(SCP-2)distributed in their molecular *** sequence control strategy provides an efficient way to decouple the mechanical and self-healing performance of polymers,which is one of the most pressing challenges in the *** relatively dispersed oxime-urethane groups in SCP-1 not only facilitate the reorganization of the dynamic covalent bonds but also increase the probability of the reformation of hydrogen *** reversible dissociation/reassociation of dynamic bonds is conducive to dissipating energy to enhance mechanical performance and promote self-healing *** a result,SCP-1 exhibits much faster self-healing than SCP-2,and its tensile strength is nearly twice that of *** addition,energy dissipation capacity and degradation behavior also show significant sequence ***,this work reveals a new molecular structure-property relationship and provides a powerful strategy to construct high-performance polymers.

关键词： sequence control dynamic polymer poly(oxime-urethane) strength polyurethane

Tetraphenylethylene-derived organic cages with persistent photogenic radicaloids and efficient photothermal conversion

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Science China Chemistry 2025年第2期68卷 661-669页

作者： Suqiong Yan Bo Yang Fanda Feng Yuan Zhang Shirong Ban Hui ma Wei huang State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China Shenzhen Research Institute of Nanjing University Shenzhen 518057China

Transformation of the electronic spin states has received significant interest in recent years because of its applications in the magnetic information storage materials and optical response ***,it can be formidably challenging to use ultraviolet(UV)light as a contactless stimulus to alter the electronic spin states of the supramolecular *** by the approach on the radical cation mechanism of the Scholl reaction and the photocyclization reactivity of tetraphenylethylene(TPE)derivatives,we report two photochromic cages(cage-TPE-1 and cage-TPE-2)that can be photochemically transformed from electron paramagnetic resonance(EPR)-silent to EPR-active form via UV irradiation due to the photo-induced electron transfer process at the TPE *** provided a strong single-electron signal with a g value of 2.003 in cage-TPE-1 and cage-TPE-2 but no signal was detected for the pristine samples without the *** transformation can be monitored by ultraviolet–visible–near-infrared(UV–vis–NIR)and photoluminescence(PL)*** photogenic radical cage intermediate was unstable in solution resulting in the degradation and intramolecular cyclization of the reactive species,while the radicals were found to be stable and persistent in the solid state due to the spin delocalization,the steric protection of confined cavities,and the oxygen *** theoretical calculations and spectral measurements suggest that the photogenic radical cage-TPE-2(•+)experiences photocyclization on the TPE *** with the close-shell cage,the radical cage-TPE-1(•+)and cage-TPE-2(•+)exhibit better photothermal conversion performance due to the incubated infrared absorption from open-shell electron feature and reduced band gap.

关键词： supramolecular cage photogenic radical photocyclization photothermal conversion

Electromagnetic wave absorption and corrosion resistance performance of carbon nanoclusters/Ce-Mn codoped barium ferrite composite materials

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International Journal of Minerals,Metallurgy and materials 2025年第3期32卷 699-709页

作者： Bo Li Lin ma Sinan Li Jiewu Cui Xiaohui Liang Wei Sun Pengjie Zhang Nan huang Song ma Zhidong Zhang Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Metallurgy Engineering Liaoning Institute of Science and TechnologyBenxi 117004China School of materials Science and Engineering Hefei University of TechnologyHefei 230009China Institute of Microelectronics Hangzhou Dianzi UniversityHangzhou 310018China BGRIMM magnetic materials&Technology Co. Ltd.Beijing 100160China

To realize the application of electromagnetic wave absorption(EWA)devices in humid marine environments,bifunctional EWA materials with better EWA capacities and anticorrosion properties have great exploration significance and systematic research *** utilizing the low-cost and excellent magnetic and stable chemical characteristics of barium ferrite(BaFe_(12)O_(19))and using the high dielectric loss and excellent chemical inertia of nanocarbon clusters,a new type of nanocomposites with carbon nanoclusters en-capsulating BaFe_(12)O_(19)was designed and synthesized by combining an impregnation method and a high-temperature calcination ***,Ce-Mn ions were introduced into the BaFe_(12)O_(19)lattice to improve the dielectric and magnetic properties of BaFe_(12)O_(19)cores significantly,and the energy band structure of the doped lattice and the orders of Ce replacing Fe sites were *** from Ce-Mn ion doping and carbon nanocluster encapsulation,the composite material exhibited excellent dual functionality of corrosion resist-ance and *** BaCe_(0.2)Mn_(0.3)Fe_(11.5)O_(19)-C(BCM-C)was calcined at 600°C,the minimum reflection loss of-20.1 dB was achieved at 14.43 *** Ku band’s effective absorption bandwidth of 4.25 GHz was achieved at an absorber thickness of only 1.3 *** BCM-C/polydimethylsiloxane coating had excellent corrosion resistance in the simulated marine environment(3.5wt%NaCl solution).The|Z|0.01Hz value of BCM-C remained at 106Ω·cm^(2)after 12 soaking *** successful preparation of the BaFe_(12)O_(19)composite en-capsulated with carbon nanoclusters provides new insights into the preparation of multifunctional absorbent materials and the fabrication of absorbent devices applied in humid marine environments in the future.

关键词： electromagnetic wave absorption anticorrosion barium ferrite cerium and manganese doping carbon nanoclusters

Atomic cerium-doped CuO_(x) catalysts for efficient electrocatalytic CO_(2) reduction to CH_(4)

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Chinese Chemical Letters 2025年第1期36卷 326-331页

作者： Xiangyu Chen Aihao Xu Dong Wei Fang huang Junjie ma Huibing He Jing Xu Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology School of Chemistry and Chemical EngineeringGuangxi UniversityNanning 530004China State Key Laboratory of Featured Metal materials and Life-cycle Safety for Composite Structures Guangxi UniversityNanning 530004China State Key Laboratory of Green Chemical Engineering and Industrial Catalysis School of Chemical EngineeringEast China University of Science and TechnologyShanghai 200237China

Copper(Cu)is widely used in the electrochemical carbon dioxide reduction reaction(ECO_(2)RR)for efficient methane(CH_(4))***,the morphology and valence of Cu-based catalysts are usually unstable under reaction *** this work,we prepared Ce-doped MOF-199 precursor(Ce/HKUST-1)and further obtained nanoparticle electrocatalyst Ce/CuO_(x)-NPs by cyclic voltammetry(CV)*** Faradic efficiency of methane(FE_(CH_(4)))maintains above 62%within a broad potential window of 350 mV and the maximum FE_(CH_(4))reaches 67.4%with a partial current density of 293 ma/cm^(2)at-1.6 V vs.a reversible hydrogen *** characterization and theoretical calculations revealed that the unique electronic structure and large ionic radius of Cerium(Ce)not only promoted the generation of key intermediate*CO but also lowered energy barrier of the*CO to*CHO *** study provides a novel and efficient catalyst for methane production in ECO_(2)RR and offers profound insights into constructing high performance Cu-based catalysts.

关键词： ECO_(2)RR Cu-based catalyst Structure evolution DFT calculation

Bacillus CotA laccase improved the intestinal health,amino acid metabolism and hepatic metabolic capacity of Pekin ducks fed naturally contaminated AFB_(1)diet

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Journal of Animal Science and Biotechnology 2025年第1期16卷 331-344页

作者： Mingxin ma Qianqian Wang Yanrong Liu Guiming Li Limeng Liu Gaigai Wang Yongpeng Guo Shimeng huang Qiugang ma Cheng Ji Lihong Zhao State Key Laboratory of Animal Nutrition and Feeding Poultry Nutrition and Feed Technology Innovation TeamCollege of Animal Science and TechnologyChina Agricultural UniversityNo.2.Yuanmingyuan West RoadBeijing 100193People’s Republic of China Poultry Institute Shandong Academy of Agricultural SciencesJinan 250100China College of Animal Science and Technology Henan Agricultural UniversityZhengzhou 450046China

Background AflatoxinB1(AFB_(1))is a prevalent contaminant in agricultural products,presenting significant risks to animal *** laccase from Bacillus licheniformis has shown significant efficacy in degrading mycotoxins in vitro *** efficacy of Bacillus CotA laccase in animals,however,remains to be confirmed.A 2×2 factorial design was used to investigate the effects of Bacillus CotA laccase level(0 or 1 U/kg),AFB_(1) challenge(challenged or unchal-lenged)and their interactions on *** purpose of this study was to evaluate the efficacy of Bacillus CotA laccase in alleviatingAFB_(1) toxicosis of *** Bacillus CotA laccase alleviatedAFB_(1)-induced declines in growth performance of ducks accompanied by improved average daily gain(ADG)and lower feed/gain ratio(F/G).Bacillus CotA laccase amelioratedAFB_(1)-induced gut barrier dysfunctions and inflammation testified by increasing the jejunal villi height/crypt depth ratio(VH/CD)and the mRNA expression of tight junction protein 1(TJP1)and zonula occluden-1(ZO-1)as well as decreasing the expression of inflammation-related genes in the jejunum of *** acid metabolome showed that Bacillus CotA laccase amelioratedAFB_(1)-induced amino acid metabolism disorders evidenced by increasing the level of glu-tamic acid in serum and upregulating the expression of amino acid transport related genes in jejunum of ***-lus CotA laccase amelioratedAFB_(1)-induced liver injury testified by suppressing oxidative stress,inhibiting apoptosis,and downregulating the expression of hepatic metabolic enzyme related genes of ***,Bacillus CotA laccase degradedAFB_(1) in digestive tract of ducks,resulting in the reduced absorption level ofAFB_(1) across intestinal epithelium testified by the decreased level ofAFB_(1)-DNA adduct in the liver,and the reduced content ofAFB_(1) residues in liver and feces of *** Bacillus CotA laccase effectively improved the growth performance,inte

关键词： AFB_(1)residue Aflatoxin Bacillus CotA laccase Duck Intestinal barrier function Liver metabolic enzyme

Nestlings of two parrotbill species can independently evaluate the presenceof predators based on acoustic cues

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Avian Research 2025年第01期 83-88页

作者： Jiaojiao Wang Peng Pan Haijie Zhang Laikun ma Qindong Zhou Longwu Wang jianhua Hou College of Life Science Hebei University Engineering Research Center of Ecological Safety and Conservation in Beijing-Tianjin-Hebei (Xiong'an New Area) of MOE Hebei Basic Science Center for Biotic Interaction Department of Biology and Food Science Hebei Normal University for Nationalities School of Life Sciences Guizhou Normal University

Nest predation is the leading cause of reproductive failure in birds and a major driving force in the evolution of anti-predation strategies. Current studies on the anti-predation strategies of birds driven by predation pressure have mainly focused on adults. However, the detection and behavioral responses of nestlings toward predation risk require further investigation. In this study, we examined nestling responses to predator sounds. Two species of nestlings, the Reed Parrotbill(Paradoxornis heudei) and Vinous-throated Parrotbill(Sinosuthora webbiana),were exposed to the Sparrowhawk(Accipiter nisus, less common) and Oriental magpie(Pica serica, more common), which are predator species, the Oriental Turtle Dove(Streptopelia orientalis), which is a commonly found harmless species, and background noise. Our findings revealed that compared to pre-playback of natural begging and playback of background noise and Oriental Turtle Dove sounds, playback of the two predator types decreased the total begging time and total number of calls of the two nestlings species, with the calls of the Sparrowhawk leading to greater suppression of nestling begging behavior than those of the Oriental ***, our results indicated that these nestlings were able to distinguish predators from harmless species based on auditory cues.

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