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Multi-layer multi-pass friction rolling additive manufacturing of Al alloy:Toward complex large-scale high-performance components

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 425-438页

作者： Haibin Liu Run Hou Chenghao Wu Ruishan Xie Shujun Chen College of Mechanical&Energy Engineering Beijing University of TechnologyBeijing 100124China Chongqing research Institute of beijing University of Technology Chongqing 401121China

At present,the emerging solid-phase friction-based additive manufacturing technology,including friction rolling additive man-ufacturing(FRAM),can only manufacture simple single-pass *** this study,multi-layer multi-pass FRAM-deposited alumin-um alloy samples were successfully prepared using a non-shoulder tool *** material flow behavior and microstructure of the over-lapped zone between adjacent layers and passes during multi-layer multi-pass FRAM deposition were studied using the hybrid 6061 and 5052 aluminum *** results showed that a mechanical interlocking structure was formed between the adjacent layers and the adja-cent passes in the overlapped center *** friction and rolling of the tool head led to different degrees of lateral flow and plastic deformation of the materials in the overlapped zone,which made the recrystallization degree in the left and right edge zones of the over-lapped zone the highest,followed by the overlapped center zone and the non-overlapped *** tensile strength of the overlapped zone exceeded 90%of that of the single-pass deposition *** is proved that although there are uneven grooves on the surface of the over-lapping area during multi-layer and multi-pass deposition,they can be filled by the flow of materials during the deposition of the next lay-er,thus ensuring the dense microstructure and excellent mechanical properties of the overlapping *** multi-layer multi-pass FRAM deposition overcomes the limitation of deposition width and lays the foundation for the future deposition of large-scale high-performance components.

关键词： aluminum alloy additive manufacturing solid-state friction stir welding multi-layer multi-pass

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Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

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Science China Chemistry 2025年第1期 233-240页

作者： Peipei Liu Yantong Li Meng-Xiang Wu Hao Kang Xiao-Li Zhao Lin Xu Linlin Liu Xiaodong Li Junfeng Fang Zhiwei Fang Ya Cheng Hai-Bo Yang Huakang Yu Xueliang Shi State key laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of Physics and Optoelectronics South China University of Technology Institute of Polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of Physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State key laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-PP/MM and 1-PM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-PP/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HPLC）, and 1-PP and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-PP/MM could be completely isomerized to 1-PM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-PM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-PM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

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Micro-strain regulation strategy to stabilize perovskite lattice based on the categories and impact of strain on perovskite solar cells

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Journal of Energy Chemistry 2025年第1期100卷 578-604页

作者： Caixia Li Wenwu Liu Shiji Da Lingbin Kong Fen Ran State key laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology School of Materials Science and Engineering Lanzhou University of Technology

Photovoltaic metal halide perovskite solar cells(PSCs) convert light to electricity more efficiently than crystalline silicon cells, and the cost of materials used to make them is lower than that of silicon *** efficiency is not a core issue affecting the application of perovskite solar cells in special *** present, stability is the major technical encounters that hinders its further commercial development. Microstrain in PSCs is currently a significant factor responsible for the device's instability. Strain-induced ion migration is widely believed to accelerate perovskite degradation even when external stimuli are ***, it is imperative to study strain to enhance the stability of PSCs. This paper reviews recent developments to understand strain's origin and effect mechanisms on performance of PSCs, including ion migration,failure behavior, defect formation, and its effect on photoelectric properties, stability, and ***, several well-known strain management strategies are systematically introduced based on the strain effect mechanism and strain engineering on the film, providing more clues for further preparation with increased stability. The manipulation of external physical strain applied from films to entire devices has been extensively studied. Furthermore, recommendations for future research directions and chemical approaches have been provided. It is emphasized that strain engineering plays a crucial role in improving the efficiency and longevity of PSCs. Tensile strain causes rapid degradation, while moderate compressive strain and external strain control could improve properties and stability. Efforts should focus on controlling compressive strain to mitigate residual tensile strain and introducing it in a controlled manner. Future research endeavors may focus on exploring these pathways to improve the efficiency and lifespan of PSCs.

关键词： Halide perovskite solar cells Strain origins Strain effects Strain management

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Nitrogen addition promotes soil carbon accumulation globally

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Science China Life Sciences 2025年第1期 284-293页

作者： Xuemei Yang Suhui Ma Erhan Huang Danhua Zhang Guoping Chen Jiangling Zhu Chengjun Ji Biao Zhu Lingli Liu Jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Ministry of Education key laboratory for Transboundary Ecosecurity of Southwest China School of Ecology and Environmental ScienceYunnan University State key laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences

Soil is the largest carbon(C) reservoir in terrestrial ecosystems and plays a crucial role in regulating the global C cycle and climate *** nitrogen(N) deposition has been widely considered as a critical factor affecting soil organic carbon(SOC) storage, but its effect on SOC components with different stability remains unclear. Here, we analyzed extensive empirical data from 304 sites worldwide to investigate how SOC and its components respond to N addition. Our analysis showed that N addition led to a significant increase in bulk SOC(6.7%), with greater increases in croplands(10.6%) and forests(6.0%) compared to grasslands(2.1%). Regarding SOC components, N addition promoted the accumulation of plant-derived C(9.7%–28.5%) over microbial-derived C(0.2%), as well as labile(5.7%) over recalcitrant components(–1.2%), resulting in a shift towards increased accumulation of plant-derived labile C. Consistently, N addition led to a greater increase in particulate organic C(11.9%) than mineral-associated organic C(3.6%), suggesting that N addition promotes C accumulation across all pools, with more increase in unstable than stable pools. The responses of SOC and its components were best predicted by the N addition rate and net primary productivity. Overall, our findings suggest that N enrichment could promote the accumulation of plant-derived and non-mineral associated C and a subsequent decrease in the overall stability of soil C pool, which underscores the importance of considering the effects of N enrichment on SOC components for a better understanding of C dynamics in soils.

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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第01期 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao key laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay laboratory State key laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State key laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan key laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

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Revealing and predicting the long-term biomechanical response of orthokeratology by developing a patient-specific computational model

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 156-168页

作者： Yifeng Li Zhuoran Yang Ziming Yan Huibin Shi Zhanli Liu Kaijie Wang Department of Engineering Mechanics School of Aerospace Engineering Tsinghua University beijing Tongren Eye Center Beijing Tongren Hospital Capital Medical University Beijing Ophthalmology & Visual Sciences Key Lab

Orthokeratology(OK) is widely used for effective myopia correction and control. However, the incomplete understanding of its biomechanical mechanisms makes OK lens fitting rely heavily on clinician judgment, complicating accurate predictions of treatment outcomes. In this paper, we performed clinical experiments and numerical analysis to study corneal deformation modes and long-term changes in central corneal thickness. Clinical experiments were conducted on 194 Chinese myopic patients under OK treatment for 3 months. Based on the experimental data, a patient-specific computational biomechanical model for OK was established and validated. Specifically, the anisotropic mechanical properties of the cornea were incorporated into the model to describe the significant difference between its shear modulus(29.5 kPa) and tensile modulus(768.4 kPa). Additionally, a viscohyperelastic material model with a prolonged corneal relaxation time of 5.6 h was developed to capture the long-term deformation response. The results show that corneal thickness reduction in OK is primarily due to out-of-plane shear deformation,influenced by the cornea's low shear resistance. Modeling the extended corneal relaxation time is crucial for predicting long-term biomechanical responses. The computational model effectively captures long-term changes in central corneal thickness, potentially improving OK lens fitting accuracy.

关键词： orthokeratology computational biomechanical model long-term viscoelasticity myopia correction

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FUBP3 mediates the amyloid-β-induced neuronal NLRP3 expression

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Neural Regeneration research 2025年第7期20卷 2068-2083页

作者： Jing Yao Yuan Li Xi Liu Wenping Liang Yu Li Liyong Wu Zhe Wang Weihong Song The National Clinical research Center for Geriatric Disease Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Neurology The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Pediatrics The Second Affiliated Hospital and Yuying Children’s HospitalKey Laboratory of Alzheimer’s Disease of Zhejiang ProvinceInstitute of AgingWenzhou Medical UniversityWenzhouZhejiang ProvinceChina Oujiang laboratory(Zhejiang laboratory for Regenerative Medicine Visionand Brain Health)WenzhouZhejiang ProvinceChina

Alzheimer's disease is characterized by deposition of amyloid-β,which forms extracellular neuritic plaques,and accumulation of hyperphosphorylated tau,which aggregates to form intraneuronal neurofibrillary tangles,in the *** NLRP3 inflammasome may play a role in the transition from amyloid-βdeposition to tau phosphorylation and *** NLRP3 is primarily found in brain microglia,and tau is predominantly located in neurons,it has been suggested that NLRP3 expressed by microglia indirectly triggers tau phosphorylation by upregulating the expression of pro-inflammatory ***,we found that neurons also express NLRP3 in vitro and in vivo,and that neuronal NLRP3 regulates tau *** biochemical methods,we mapped the minimal NLRP3 promoter and identified FUBP3 as a transcription factor regulating NLRP3 expression in *** primary neurons and the neuroblastoma cell line Neuro2A,FUBP3 is required for endogenous NLRP3 expression and tau phosphorylation only when amyloid-βis *** the brains of aged wild-type mice and a mouse model of Alzheimer's disease,FUBP3 expression was markedly increased in cortical *** analysis suggested that FUBP3 plays a role in neuron-mediated immune *** also found that FUBP3 trimmed the 5′end of DNA fragments that it bound,implying that FUBP3 functions in stress-induced *** findings suggest that neuronal NLRP3 may be more directly involved in the amyloid-β-to–phospho-tau transition than microglial NLRP3,and that amyloid-βfundamentally alters the regulatory mechanism of NLRP3 expression in *** that FUBP3 was only expressed at low levels in young wild-type mice and was strongly upregulated in the brains of aged mice and Alzheimer's disease mice,FUBP3 could be a safe therapeutic target for preventing Alzheimer's disease progression.

关键词： 5′end trimming Alzheimer's disease amyloid-beta amyloid-β-dependent transcription FUBP3 inflammasome inflammation neuron NLRP3 tau transcription factor

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EZH2-dependent myelination following sciatic nerve injury

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Neural Regeneration research 2025年第8期20卷 2382-2394页

作者： Hui Zhu Li Mu Xi Xu Tianyi Huang Ying Wang Siyuan Xu Yiting Wang Wencong Wang Zhiping Wang Hongkui Wang Chengbin Xue research Center of Clinical Medicine Affiliated Hospital of Nantong UniversityKey Laboratory of Neuroregeneration of Jiangsu and Ministry of EducationCo-innovation Center of NeuroregenerationNMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology ProductsNantong UniversityNantongJiangsu ProvinceChina Medical School of Nantong University NantongJiangsu ProvinceChina Department of Neurology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Rehabilitation Medicine Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Department of Critical care Medicine Nantong Fourth People’s HospitalNantongJiangsu ProvinceChina

Demyelination and remyelination have been major focal points in the study of peripheral nerve regeneration following peripheral nerve ***,the gene regulatory network of regenerated myelin differs from that of native *** of enhancer of zeste homolog 2(EZH2)hinders the differentiation,maturation,and myelination of Schwann cells in *** further determine the role of EZH2 in myelination and recovery post-peripheral nerve injury,conditional knockout mice lacking Ezh2 in Schwann cells(Ezh2^(fl/fl);Dhh-Cre and Ezh2^(fl/fl);Mpz-Cre)were *** results show that a significant proportion of axons in the sciatic nerve of Ezh2-depleted mice remain *** highlights the crucial role of Ezh2 in initiating Schwann cell ***,we observed that 21 days after inducing a sciatic nerve crush injury in these mice,most axons had remyelinated at the injury site in the control nerve,while Ezh2^(fl/fl);Mpz-Cre mice had significantly fewer remyelinated axons compared with their wild-type *** suggests that the absence of Ezh2 in Schwann cells impairs myelin formation and *** conclusion,EZH2 has emerged as a pivotal regulatory factor in the process of demyelination and myelin regeneration following peripheral nerve *** EZH2 activity during these processes may offer a promising therapeutic target for the treatment of peripheral nerve injuries.

关键词： demyelination EZH2 myelination peripheral nerve injury PRC2 remyelination Schwann cells sciatic nerve crush sciatic nerve transection

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Fabrication of carbon-supported Al2O3 nanoparticles via spontaneous cross-linking to enhance selective hydrogenation of furfural

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Journal of Energy Chemistry 2025年第1期100卷 612-620页

作者： Weiwei Yu Xinbao Zhang Hongyu Chen Yanan Wang Shaoguo Li Fucun Chen Zhenni Liu Xiujie Li Xiangxue Zhu State key laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=***,a novel Al2O3/C-u hybrid catalyst,composed of N-modified dendritic carbon networks supporting Al2O3nanoparticles,was successfully prepared via carbonizing the freeze-dried gel from spontaneous cross-linking of alginate,Al3+and *** obtained carbon-supported Al2O3hybrid catalyst has a high ratio （31%） of Al species in pentahedral-coordinated *** introduction of urea enhances the surface N content,the ratio of pyrrolic N,and specific surface area of catalyst,leading to improved adsorption capacity of C=O and the accessibility of active *** the furfural hydrogenation reaction with isopropyl alcohol as hydrogen donor,Al2O3/C-u catalyst achieved a 90%conversion of furfural with 98.0% selectivity to furfuryl alcohol,outperforming that of commercial γ-***,Al2O3/C-u demonstrates excellent catalytic stability in the recycling tests attributed to the synergistic effect of abundant weak Lewis acid sites and the anchoring effect of the carbon network on *** work provides an innovative and facile strategy for fabrication of carbon-supported Al2O3hybrid catalysts with rich AlVspecies,serving as a high selective hydrogenation catalyst through MPV reaction route.

关键词： Selective hydrogenation Furfural Furfuryl alcohol Cross-linking MPV route

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Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation

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Traditional Medicine research 2025年第2期10卷 1-15页

作者： Xu Liang Ni-Hui Zhang Zhi-Lai Zhan Guang-Lu Chang Yan Gao Xia Li Wen-Yuan Gao School of Pharmaceutical Science and Technology Faculty of MedicineTianjin UniversityTianjin 300193China State key laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs China Academy of Chinese Medical SciencesBeijing 100700China key laboratory of Modern Chinese Medicine Resources research Enterprises Tianjin 300402China

Background:Rosa chinensis *** Rosa rugosa *** not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional *** two plants have some differences in efficacy,but the flower buds are easily confused for similar *** addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal ***,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography ***,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large *** compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and ***:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the *** principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four *** least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavon

关键词： Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics chemometrics multiple component quantification quality evaluation

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