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Investigation of magnesium phosphate cement on river dredged sludge with varying humic acid content and solidification mechanism

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Journal of Rock Mechanics and Geotechnical Engineering 2025年第1期17卷 573-585页

作者： Xiaoyi Yuan lei Peng bing Chen Department of Civil Engineering Shanghai Jiao Tong UniversityShanghai200240China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai200240China

This paper investigated the use of magnesium phosphate cement (MPC) for solidifying sludge with different humic acid (HA) content (ranging from 0 to 4.5%) and explored the solidification mechanism. Fluidity, setting time, unconfined compressive strength (UCS), the strength formation mechanism, and the spontaneous imbibition process of solidified sludge (SS) were studied. The results indicate that MPC can be used as a low-alkalinity curing agent. As the HA content increases, fluidity and setting time also increase, while hydration temperature and strength decrease. Additionally, the failure mode of SS transitions from brittleness to ductility. The strength of SS is composed of the cementation strength provided by MPC hydration products, matric suction, osmotic suction, and the structural strength of the sludge. MPC reduces the structural strength caused by the shrinkage of pure sludge under the action of matric suction, but the incorporation of MPC significantly improved the strength when the sludge is eroded by water. X-ray diffraction (XRD) and scanning electron microscopy (SEM) show that the sludge and MPC can form a dense solid body, forming various hydration products, and synergistically improve the mechanical properties of the sludge.

关键词： Sludge solidification MPC Unsaturated spontaneous imbibition Strength mechanism Humic acid

Synthesis of intermetallic PtCo fuel cell catalysts from bimetallic core@shell structured nanoparticles

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Journal of Energy Chemistry 2025年第2期101卷 1-6页

作者： Le Zhang lei Tong Shuai Li Chang-Song Ma kun-Ze Xue Hai-Wei Liang Hefei National Research Center for Physical Sciences at the Microscale Department of Chemistry University of Science and Technology of China

The high activity and stability of intermetallic PtCo nanocatalysts toward oxygen reduction reaction make them a top candidate as low-Pt cathode catalysts in proton exchange membrane fuel cells（PEMFCs）.However,forming intermetallic structures typically requires high-temperature annealing,posing a challenge for achieving well-size control and highly ordered *** we report the design and synthesis of bimetallic co re@shell structured precursors for affording high-performance intermetallic PtCo *** fabrication of the core@shell precursor involves using a molecular ligand containing both sulfur and oxygen donors to selectively bind with Pt colloidal nanoparticles as the core and chelate Co ions as the *** high-temperature annealing,the ligand transforms into carbon coatings around alloy nanoparticles,preventing particle sintering;meanwhile,Co ions in the shell can easily diffuse into the Pt core,which helps to increase the thermodynamic driving force for forming intermetallic *** benefits enable us to obtain the catalyst with finely dispersed nanoparticles（～3.5 nm）and a high ordering degree of 72%.With 0.1 mgPt/cm2cathode loading,the catalyst delivers superior performance and durability in PEMFCs,showing an initial mass activity of 0.56 A/mgPt,an initial power density of 1.05 W/cm2at 0.67 V（H2-air）,and a voltage loss of 26 mV at 0.8 A/cm2after the accelerated durability test.

关键词： Bimetallic structure Fuel cells Intermetallic PtCo Oxygen reduction reaction

A comparative study on the formation of nitrogen-containing organic compounds in cloud droplets and aerosol particles

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Journal of Environmental Sciences 2025年第3期149卷 456-464页

作者： Guohua Zhang TaoWang Qinhao Lin kun Liu Wei Sun Duohong Chen lei Li Xinming Wang Xinhui Bi State Key Laboratory of Organic Geochemistry and Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization Guangzhou Institute of GeochemistryChinese Academy of Sciences(CAS)Guangzhou 510640China Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control Guangzhou Institute of GeochemistryCASGuangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China School of Environmental Science and Engineering Institute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China State Environmental Protection Key Laboratory of Regional Air Quality Monitoring Guangdong Environmental Monitoring CenterGuangzhou 510308China Institute of Mass Spectrometer and Atmospheric Environment Jinan UniversityGuangzhou 510632China

Nitrogen-containing organic compounds(NOCs)may potentially contribute to aqueous secondary organic aerosols,yet the different formation of NOCs in aerosol particles and cloud droplets remains *** the in-situ measurements performed at a mountain site(1690 m a.s.l.)in southern China,we investigated the formation of NOCs in the cloud droplets and the cloud-free particles,based on their mixing state information of NOCscontaining particles by single particle mass *** relative abundance of NOCs in the cloud-free particles was significantly higher than those in cloud residual(cloud RES)*** were highly correlated with carbonyl compounds(including glyoxalate and methylglyoxal)in the cloud-free particles,however,limited correlation was observed for cloud RES *** of their mixing state and temporal variations highlights that NOCs was mainly formed from the carbonyl compounds and ammonium in the cloud-free particles,rather than in the cloud RES *** results support that the formation of NOCs from carbonyl compounds is facilitated in concentrated solutions in wet aerosols,rather than cloud *** addition,we have identified the transport of biomass burning particles that facilitate the formation of NOCs,and that the observed NOCs is most likely contributed to the light *** findings have implications for the evaluation of NOCs formation and their contribution to light absorption.

关键词： Nitrogen-containing organic compounds Individual particles Cloud Carbonyl compounds Mixing state

Peripheral blood RNA biomarkers can predict lesion severity in degenerative cervical myelopathy

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Neural Regeneration Research 2025年第6期20卷 1764-1775页

作者： Zhenzhong Zheng Jialin Chen Jinghong Xu Bin Jiang lei Li Yawei Li Yuliang Dai bing Wang Department of Spine Surgery The Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina

Degenerative cervical myelopathy is a common cause of spinal cord injury,with longer symptom duration and higher myelopathy severity indicating a worse *** numerous studies have investigated serological biomarkers for acute spinal cord injury,few studies have explored such biomarkers for diagnosing degenerative cervical *** study involved 30 patients with degenerative cervical myelopathy(51.3±7.3 years old,12 women and 18 men),seven healthy controls(25.7±1.7 years old,one woman and six men),and nine patients with cervical spondylotic radiculopathy(51.9±8.6 years old,three women and six men).Analysis of blood samples from the three groups showed clear differences in transcriptomic *** analysis identified 128 differentially expressed genes that were enriched in patients with neurological *** least absolute shrinkage and selection operator analysis,we constructed a five-gene model(TBCD,TPM2,PNKD,EIF4G2,and AP5Z1)to diagnose degenerative cervical myelopathy with an accuracy of 93.5%.One-gene models(TCAP and SDHA)identified mild and severe degenerative cervical myelopathy with accuracies of 83.3%and 76.7%,*** of two immune cell types(memory B cells and memory-activated CD4^(+)T cells)predicted levels of lesions in degenerative cervical myelopathy with 80%*** results suggest that peripheral blood RNA biomarkers could be used to predict lesion severity in degenerative cervical myelopathy.

关键词： biomarkers candidate genes degenerative cervical myelopathy gene expression analysis immune cell types neurological disabilities peripheral blood RNA profiles spinal cord injury

The Influence of Heterogeneous Processes on the Physicochemical Properties of Atmospheric Aerosols

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Advances in Atmospheric Sciences 2025年第4期42卷 623-640页

作者： Maofa GE Shengrui TONG Lin DU Lingyan WU Ting lei kun LI Minglan XU Narcisse T.TSONA Wenqian ZHANG Hailiang ZHANG State Key Laboratory for Structural Chemistry of Unstable and Stable Species Beijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing 100049China Environment Research Institute Shandong UniversityQingdao 266237China State Key Laboratory of Severe Weather&Key Laboratory of Atmospheric Chemistry of CMA Chinese Academy of Meteorological SciencesBeijing 100081China

With the rapid development of the world economy,complex air pollution has increasingly become a serious threat;for example,with haze events occurring frequently in various regions of the *** evidence has indicated that secondary aerosols play an important role in haze formation,and that heterogeneous processes are among the main forces driving their explosive *** this regard,this paper reviews recent advances in the understanding of the impact of heterogeneous processes on haze chemistry,including the impact on NO_(2)chemistry,marine aerosols,and the hygroscopicity and optical properties of atmospheric *** is distinguished from past reviews on this topic by focusing mainly on new insights from the past five *** summarize the main findings of the impacts of heterogeneous processes on NO_(2)chemistry,marine aerosols,and the physicochemical properties of atmospheric aerosols,and propose several future research directions.

关键词： heterogeneous chemistry atmosphere aerosols physicochemical properties

Factor-adjusted tests for generalized linear models with multimodal data:An application to breast cancer data

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Science China Mathematics 2025年第2期68卷 447-484页

作者： Dongyu Li lei Wang School of Statistics and Data Science KLMDASRLEBPSand LPMCNankai UniversityTianjin 300071China

With the advancement of modern scientific research,multimodal data is increasingly being collected from multiple sources or *** outcomes derived from generalized linear models with high-dimensional and multimodal covariates,we develop two distinct factor-adjusted tests to assess the significance of high-dimensional modality data and specific low-dimensional linear combinations of predictors from one or more modalities,***,we propose a factor-adjusted decorrelated score test to evaluate the significance of a single *** approach simultaneously transforms a high-dimensional test into a fixed low-dimensional one while addressing the impact of high-dimensional nuisance ***,we construct a factor-adjusted Wald test based on partial penalized estimation to assess the significance of certain low-dimensional combinations of variables from one or more *** limiting distributions of these two proposed tests are analyzed under both the null hypothesis and local alternatives to characterize the asymptotic type-I errors and *** finite sample performance of our proposed tests is evaluated through simulations and further demonstrated with a breast cancer dataset.

关键词： decorrelated score factor model high-dimensional data integrative analysis partial penalized Wald test

Liquid metal catalyst for ammonia synthesis at low pressure

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Science China Materials 2025年第2期68卷 681-682页

作者： Ziyue Zeng Chenyang Wang lei Fu College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China The Institute for Advanced Studies Wuhan UniversityWuhan 430072China

Liquid metal(LM)has attracted immense interest as a novel catalyst in the past few years for its distinctive physicochemical properties,encompassing superior electrical and thermal conductivities,as well as exceptional fluidity characteristics at low temperatures[1].In contrast to conventional solid heterogeneous catalysts,the fluidic characteristics of liquid metal catalysts enhance the interaction between catalysts and reactants,boosting mass transfer at the reaction interface.

关键词： catalyst ammonia synthesis

Automatic and Rapid Throughflow-Based Optimal Design Method for Multi-Stage Axial-Flow Compressors

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Journal of Thermal Science 2025年第1期34卷 77-91页

作者： lei Fan ZHANG Xiawen JU Yaping ZHANG Chuhua Department of Fluid Machinery and Engineering School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an 710049China State Key Laboratory for Strength and Vibration of Mechanical Structures Xi'an Jiaotong UniversityXi'an 710049China Production and Environmental Department China Huaneng Group.Co.Ltd.Beijing 100031China

Throughflow design has the advantages of less time consumption and large optimization space,and thus is the corner stone of advanced design system of multi-stage axial-flow *** majority of relevant studies were limited to the throughflow inverse designs,and quite few works have been till now devoted to the throughflow optimal *** this work,an automatic and rapid throughflow-based optimal design method is proposed for axial-flow compressors in which a throughflow inverse design solver is embedded in optimal genetic algorithm to improve the design efficiency of axial-flow *** types of design parameters in the throughflow inverse design of axial-flow compressors,i.e.,swirl and shroud curve,are simultaneously used to optimize both the blade shape and flow *** proposed method is validated by the redesign optimization of the benchmark axial-flow compressor NASA Stage 35,and the CFD predictions show that the throughflow-based optimization leads to 1.18% efficiency benefit at design *** proposed method is then utilized to the two-dimensional throughflow optimal design of a large-scale 6.5-stage axial-flow industrial *** optimal design results are confirmed by CFD predictions,indicating that the proposed method can effectively improve the design adiabatic efficiency of the compressors by 1.09% within a few minutes on desk-top *** throughflow design implications are also obtained for advanced axial-flow industrial *** work could enhance the capability of throughflow design method and has engineering application value to explore the throughflow optimization space of multi-stage axial-flow compressors.

关键词： multi-stage axial-flow compressor throughflow design empirical correlations genetic algorithm aerodynamic optimization

Attention Eraser and Quantitative Measures for Automated Bone Age Assessment

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Computers, Materials & Continua 2025年第1期82卷 627-644页

作者： Liuqiang Shu lei Yu College of Computer and Information Science Chongqing Normal UniversityChongqing401331China

Bone age assessment(BAA)aims to determine whether a child’s growth and development are normal concerning their chronological *** predict bone age more accurately based on radiographs,and for the left-hand X-ray images of different races model can have better adaptability,we propose a neural network in parallel with the quantitative features from the left-hand bone measurements for *** this study,a lightweight feature extractor(LFE)is designed to obtain the featuremaps fromradiographs,and amodule called attention erasermodule(AEM)is proposed to capture the fine-grained ***,the dimensional information of the metacarpal parts in the radiographs is measured to enhance the model’s generalization capability across images fromdifferent *** is trained and validated on the RSNA,RHPE,and digital hand atlas datasets,which include images from various racial *** model achieves a mean absolute error(MAE)of 4.42 months on the RSNA dataset and 15.98 months on the RHPE *** to ResNet50,InceptionV3,and several state-of-the-art methods,our proposed method shows statistically significant improvements(p<0.05),with a reduction in MAE by 0.2±0.02 years across different racial ***,t-tests on the features also confirm the statistical significance of our approach(p<0.05).

关键词： Bone age assessment attention eraser quantitative feature metacarpal bones