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Directional Three‑Dimensional Macroporous Carbon Foams Decorated with WC_(1−x)Nanoparticles Derived from Salting‑Out Protein Assemblies for Highly Effective Electromagnetic Absorption
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作者 Yongzheng Chen Lixue Gai +5 位作者 Bo Hu Yan Wang Yanyi Chen Xijiang Han Ping Xu Yunchen Du 《Nano-Micro Letters》 2026年第3期1-21,共21页
Directional three-dimensional carbon-based foams are emerging as highly attractive candidates for promising electromagnetic wave absorbing materials(EWAMs)thanks to their unique architecture,but their construction usu... Directional three-dimensional carbon-based foams are emerging as highly attractive candidates for promising electromagnetic wave absorbing materials(EWAMs)thanks to their unique architecture,but their construction usually involves complex procedures and extremely depends on unidirectional freezing technique.Herein,we propose a groundbreaking approach that leverages the assemblies of salting-out protein induced by ammonium metatungstate(AM)as the precursor,and then acquire directional three-dimensional carbon-based foams through simple pyrolysis.The electrostatic interaction between AM and protein ensures well dispersion of WC_(1−x)nanoparticles on carbon frameworks.The content of WC_(1−x)nanoparticles can be rationally regulated by AM dosage,and it also affects the electromagnetic(EM)properties of final carbon-based foams.The optimized foam exhibits exceptional EM absorption performance,achieving a remarkable minimum reflection loss of−72.0 dB and an effective absorption bandwidth of 6.3 GHz when EM wave propagates parallel to the directional pores.Such performance benefits from the synergistic effects of macroporous architecture and compositional design.Although there is a directional dependence of EM absorption,radar stealth simulation demonstrates that these foams can still promise considerable reduction in radar cross section with the change of incident angle.Moreover,COMSOL simulation further identifies their good performance in preventing EM interference among different electronic components. 展开更多
关键词 3D macroporous carbon-based foams Directional pore channels Salting-out protein assemblies EM wave absorption Directional dependence
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Increasing Elevation Reduces Complexity of Soil Microbial Co-occurring Network in Changbai Mountains,China
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作者 LIU Xue WU Haitao +4 位作者 GUAN Qiang LU Kangle LIU Dandan KANG Yujuan ZHANG Shixiu 《Chinese Geographical Science》 2026年第2期306-319,I0004-I0006,共17页
Elevation patterns and assembly processes of soil microbial community structures are essential for understanding biogeo-chemical processes in mountain systems.Differences in soil properties caused by elevation gradien... Elevation patterns and assembly processes of soil microbial community structures are essential for understanding biogeo-chemical processes in mountain systems.Differences in soil properties caused by elevation gradients can regulate the spatial distribu-tion and network complexity of the community structure.To explore the variations in soil microbial community structures and their as-sembly mechanisms across different elevations of the Changbai Mountains,as well as their responses to environmental factors,we col-lected microbial samples along an elevational gradient(seven elevations containing four vegetation zones)on the western slope of the Changbai Mountains using the method of metagenomic sequencing.The results showed a significant difference(P<0.05)for the Chao1 index across different elevations,but no significant difference was observed for the Shannon and Simpson indices.With increasing elev-ation,the number of nodes and links in the microbial network gradually decreased.Acidobacteria were highly connected to many nodes.The microbial communities indicated a significant distance-decay relationship(P<0.001)and were affected more by stochastic pro-cesses along the elevation gradient.The results of the Structural Equation Model(SEM)showed that elevation had direct significant ef-fect on carbon(C,P<0.01),nitrogen(N,P<0.01),and phosphorus(P,P<0.05)and weak negative effect on their ecological stoi-chiometry.Elevation was one of the major variables contributing to microbial network topology.The contribution of C and N to micro-bial network complexity was higher than that of P.Our study provides valuable insights into the responses of soil microbial communit-ies to elevation variations. 展开更多
关键词 assembly processes co-occurring network elevation gradient microbial community soil nutrient Changbai Mountains China
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Converging assemblies:A putative building block for brain function and for interfacing with the brain
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作者 Eran Stark Lidor Spivak 《Neural Regeneration Research》 2026年第3期1124-1125,共2页
The organization of biological neuronal networks into functional modules has intrigued scientists and inspired engineers to develop artificial systems.These networks are characterized by two key properties.First,they ... The organization of biological neuronal networks into functional modules has intrigued scientists and inspired engineers to develop artificial systems.These networks are characterized by two key properties.First,they exhibit dense interconnectivity(Braitenburg and Schüz,1998;Campagnola et al.,2022).The strength and probability of connectivity depend on cell type,inter-neuronal distance,and species.Still,every cortical neuron receives input from thousands of other neurons while transmitting output to a similar number of neurons.Second,communication between neurons occurs primarily via chemical or electrical synapses. 展开更多
关键词 cortical neuron INTERCONNECTIVITY neuronal networks functional modules dense interconnectivity braitenburg artificial systemsthese converging assemblies biological neuronal networks
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Entropy regulation induced hollow prismatic structural NiCoFeInZnV-based layered double hydroxide with prominent electrochemical kinetics and stability for aqueous zinc-ion batteries
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作者 Liu Yang Tao Zou +9 位作者 Haihui Wu Jiqing Zhang Xuekun Sui Wenjing Zhang Ende Feng Xiaohui Guan Bao Liu Jingru Bai Penggang Yin Guangsheng Wang 《Journal of Energy Chemistry》 2026年第1期274-283,I0007,共11页
Layered double hydroxides(LDHs)hold great promise as cathode materials for aqueous zinc-ion batteries(AZIBs).Nevertheless,they also face challenges of sluggish kinetics and rapid capacity loss.Herein,a conformational ... Layered double hydroxides(LDHs)hold great promise as cathode materials for aqueous zinc-ion batteries(AZIBs).Nevertheless,they also face challenges of sluggish kinetics and rapid capacity loss.Herein,a conformational entropy regulation strategy has been applied to surmount the shortcomings.A medium-entropy iron-based metal organic framework(MIL-88)derived NiCoFeInZnV-based layered double hydroxide with carbon loaded(ME-NiCoFeInZnV-LDH/C)has been first proposed and prepared with a designed method.The increased entropy optimizes electron conductivity and alleviates structure alteration and diffusion barrier during interactions with charge carriers,due to electron-induced effect and“cocktail”effect.Moreover,the nanosheet assembled hollow prismatic structures could homogenize flux distribution and electric field distribution.Therefore,the electrochemical kinetics,crystal structure stability,and activity could be dramatically improved.Leveraging the advantages of structure and composition regulation,Zn||ME-NiCoFeInZnV-LDH/C zinc battery delivers high specific capacities,rate performance,and cycling stability.This work proposes a novel and feasible medium-entropy strategy to prepare a high-performance cathode for advanced AZIBs,which is of prominent significance for the development of charge storage devices. 展开更多
关键词 Medium-entropy strategy ME-NiCoFeInZnV-LDH/C Nanosheet assembled hollow prismatic structures Aqueous zinc-ion batteries Improved electrochemical kinetics and activity
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Textured Asymmetric Membrane Electrode Assemblies of Piezoelectric Phosphorene and Ti_(3)C_(2)T_(x)MXene Heterostructures for Enhanced Electrochemical Stability and Kinetics in LIBs
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作者 Yihui Li Juan Xie +10 位作者 Ruofei Wang Shugang Min Zewen Xu Yangjian Ding Pengcheng Su Xingmin Zhang Liyu Wei Jing‑Feng Li Zhaoqiang Chu Jingyu Sun Cheng Huang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第4期394-414,共21页
Black phosphorus with a superior theoretical capacity(2596 mAh g^(-1))and high conductivity is regarded as one of the powerful candidates for lithium-ion battery(LIB)anode materials,whereas the severe volume expansion... Black phosphorus with a superior theoretical capacity(2596 mAh g^(-1))and high conductivity is regarded as one of the powerful candidates for lithium-ion battery(LIB)anode materials,whereas the severe volume expansion and sluggish kinetics still impede its applications in LIBs.By contrast,the exfoliated two-dimensional phosphorene owns negligible volume variation,and its intrinsic piezoelectricity is considered to be beneficial to the Li-ion transfer kinetics,while its positive influence has not been discussed yet.Herein,a phosphorene/MXene heterostructure-textured nanopiezocomposite is proposed with even phosphorene distribution and enhanced piezo-electrochemical coupling as an applicable free-standing asymmetric membrane electrode beyond the skin effect for enhanced Li-ion storage.The experimental and simulation analysis reveals that the embedded phosphorene nanosheets not only provide abundant active sites for Li-ions,but also endow the nanocomposite with favorable piezoelectricity,thus promoting the Li-ion transfer kinetics by generating the piezoelectric field serving as an extra accelerator.By waltzing with the MXene framework,the optimized electrode exhibits enhanced kinetics and stability,achieving stable cycling performances for 1,000 cycles at 2 A g^(-1),and delivering a high reversible capacity of 524 m Ah g^(-1)at-20℃,indicating the positive influence of the structural merits of self-assembled nanopiezocomposites on promoting stability and kinetics. 展开更多
关键词 Phosphorene Nanopiezocomposite Piezo-electrochemical coupling Membrane electrode assembly Lithium-ion storage
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Hierarchical lichee-like Fe_(3)O_(4) assemblies and their high heating efficiency in magnetic hyperthermia
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作者 Wen-Yu Li Wen-Tao Li +5 位作者 Bang-Quan Li Li-Juan Dong Tian-Hua Meng Ge Huo Gong-Ying Liang Xue-Gang Lu 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第10期394-399,共6页
A nontoxic and biocompatible thermoseed is developed for the magnetic hyperthermia.Two kinds of thermoseed materials:hierarchical hollow and solid lichee-like Fe_(3)O_(4) assemblies,are synthesized by a facile hydroth... A nontoxic and biocompatible thermoseed is developed for the magnetic hyperthermia.Two kinds of thermoseed materials:hierarchical hollow and solid lichee-like Fe_(3)O_(4) assemblies,are synthesized by a facile hydrothermal method.The crystal structure of Fe_(3)O_(4) assemblies are characterized by x-ray diffraction,scanning electron microscopy,and transmission electron microscopy.Moreover,the prepared Fe_(3)O_(4) assemblies are used as a magnetic heat treatment agent,and their heating efficiency is investigated.Compared to solid assembly,hollow lichee-like Fe_(3)O_(4) assembly exhibits a higher specific absorption rate of 116.53 W/g and a shorter heating time,which is ascribed to its higher saturation magnetization,larger initial particle size,and the unique hierarchical hollow structure.Furthermore,the magnetothermal effect is primarily attributed to Neel relaxation.Overall,we propose a facile and convenient approach to enhance the heating efficiency of magnetic nanoparticles by forming hollow hierarchical assemblies. 展开更多
关键词 magnetic hyperthermia heating efficiency hierarchical Fe_(3)O_(4)assemblies
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Species invasion and phylogenetic relatedness of vascular plants on the Qinghai-Tibet Plateau,the roof of the world 被引量:1
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作者 Hong Qian Tao Deng 《Plant Diversity》 2025年第6期883-888,共6页
The Qinghai-Tibet Plateau(QTP)is the highest and one of the most extensive plateaus in the world.Investigating naturalized non-native plant species composition,phylogenetic relationships among naturalized plant specie... The Qinghai-Tibet Plateau(QTP)is the highest and one of the most extensive plateaus in the world.Investigating naturalized non-native plant species composition,phylogenetic relationships among naturalized plant species,and phylogenetic relationships between native and naturalized plant species on the plateau is of great importance.Here,we analyze a comprehensive dataset including all species of native and naturalized vascular plants known to occur in the core part of the QTP.We use net relatedness index(NRI)and nearest taxon index(NTI),which reflect deep and shallow evolutionary histories,respectively,to quantify phylogenetic relatedness among angiosperm species.The QTP included in this study(1,448,815 km^(2))has 9086 and 314 species of native and naturalized non-native vascular plants,respectively.We find that the naturalized angiosperm species are phylogenetically clustered with respect to the species pool including all native and naturalized angiosperm species on the QTP included in this study,regardless of whether NRI or NTI is used.For the eight regions within the QTP included in this study,NRI and NTI of naturalized angiosperms are positive in seven regions with respect to their respective regional species pools,reflecting phylogenetic clustering.Thus,naturalized angiosperm species are a phylogenetically clustered subset of all angiosperm species on the QTP,regardless of whether the studied plateau as a whole or its constituent regions are considered. 展开更多
关键词 Community assembly Exotic species Introduced species Naturalized species Vascular plants
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Gossypium latifolium genome reveals the genetic basis of domestication of upland cotton from semi-wild races to cultivars 被引量:1
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作者 Chao Fu Nian Wang +7 位作者 Qingying Meng Zhiyong Xu Yu Le Xianlong Zhang Yangyang Wei Renhai Peng Chao Shen Zhongxu Lin 《The Crop Journal》 2025年第3期929-941,共13页
The genetic basis for Gossypium hirsutum race latifolium,the putative ancestor of cultivated upland cotton,emerging from the semi-wild races to be domesticated into cultivated upland cotton is unknown.Here,we reported... The genetic basis for Gossypium hirsutum race latifolium,the putative ancestor of cultivated upland cotton,emerging from the semi-wild races to be domesticated into cultivated upland cotton is unknown.Here,we reported a high-quality genome assembly of G.latifolium.Comparative genome analyses revealed substantial variations in both gene group composition and genomic sequences across 13 cotton genomes,including the expansion of photosynthesis-related gene groups in G.latifolium compared with other races and the pivotal contribution of structural variations(SVs)to G.hirsutum domestication.Based on the resequencing reads and constructed pan-genome of upland cotton,co-selection regions and SVs with significant frequency differences among different populations were identified.Genes located in these regions or affected by these variations may characterize the differences between G.latifolium and other races,and could be involved in maintenance of upland cotton domestication phenotypes.These findings may assist in mining genes for upland cotton improvement and improving the understanding of the genetic basis of upland cotton domestication. 展开更多
关键词 G.latifolium Genome assembly Comparative genome analysis Structural variations DOMESTICATION
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基于改进RPM-Net和多约束装配面权重分配的装配精度预测方法
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作者 邹鑫 项四通 +1 位作者 王逸航 杨建国 《仪器仪表学报》 北大核心 2025年第12期173-187,共15页
在机械系统中,装配误差是影响整机运行精度和综合性能的关键因素之一。然而,目前在装配误差预测方面,存在预测值与实际值相差较大的问题,这严重影响了机械系统的装配质量和后续性能优化。针对这一问题,提出了一种基于改进鲁棒点匹配网络... 在机械系统中,装配误差是影响整机运行精度和综合性能的关键因素之一。然而,目前在装配误差预测方面,存在预测值与实际值相差较大的问题,这严重影响了机械系统的装配质量和后续性能优化。针对这一问题,提出了一种基于改进鲁棒点匹配网络(RPM-Net)和多约束装配面权重分配的装配精度预测方法。在零件配合误差获取方面,通过采用点云配准技术对装配面点云进行高精度对齐,以获取装配面之间的几何关系和误差信息。在配准过程中,通过将注意力机制嵌入RPM-Net框架,加强了网络对重要特征信息的关注,有效抑制了配准陷入局部最优的风险,显著提升了装配面点云的配准精度,为后续的误差传递分析提供了更加可靠的数据基础。在零件配合误差传递方面,依据各装配面对末端位姿的影响程度,对构成多约束的装配面旋量进行加权求和,对非重复约束旋量进行复合运算。这种处理方式能够保证预测结果可以全面考虑各装配面旋量的影响,避免了传统方法中因忽略某些装配面旋量而导致的预测偏差,进而提升装配精度预测的准确性。实验结果表明,该方法在空间5个自由度上的预测偏差与实际值偏差被精准锁定在2μm和4×10^(-5) rad以内,相较于传统串联方法和代数运算方法能够更准确地反映实际装配情况,为后续提高装配精度提供了有效的模型参考。 展开更多
关键词 点云测量 点云配准 权重分配 多约束装配 装配精度
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Fabrication of assembled and welded Ag/W nanowire composite networks as electrodes for body motion monitoring and flexible heaters
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作者 Jian-Jun Gao Ji-Hui Lin +3 位作者 Xia-Heng Zhang Lin-Peng Zhu Hong-Ling Qin Li-Gang Yao 《Rare Metals》 2025年第2期1147-1159,共13页
Multifunctional flexible sensors as wearable electronic systems have attracted considerable attention for mimicking human skin to sense ambient stimuli.However,sensors need to have high resolution,stability and sensit... Multifunctional flexible sensors as wearable electronic systems have attracted considerable attention for mimicking human skin to sense ambient stimuli.However,sensors need to have high resolution,stability and sensitivity to realize fully biomimetic skin.Here,an assembled and welded Ag/W composite nanowire flexible electrode was prepared for body motion monitoring and flexible heaters.This Ag/W composite nanowire flexible electrode has a high transmittance of 90.1%(at 121Ω·sq^(−1) sheet resistance)and a low sheet resistance of 27Ω·sq^(−1)(at 60.1%transmittance).Although the transparency of this electrode is not high,the fluctuation in relative resistance change rate at 10%strain is only 5%after 1000 tensile cycles.It can be employed to monitor human body motions,including bending of fingers,arms,wrists,and throat action.Meanwhile,the Ag/W nanowires composite film heater achieves a steady-state temperature of up to 100℃ at a constant voltage of 3.5 V and an instantaneous heating rate of up to 36.5℃·s^(−1). 展开更多
关键词 Ag/W nanowire ASSEMBLE Welding Body motion monitoring Flexible heater
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Engineering tiramisu-like phase change nanocomposite for superior thermal energy management and electromagnetic interference shielding
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作者 Boyang Hu Hong Guo +5 位作者 Ting Li Xiwei Cao Min Cao Weiyan Qi Ying Cui Baoan Li 《Journal of Materials Science & Technology》 2025年第3期113-124,共12页
Exploiting advanced nanocomposites isochronally integrating outstanding thermal conductivity(TC)and electromagnetic interference shielding effectiveness(EMI SE)can boost the cutting-edge application of phase change ma... Exploiting advanced nanocomposites isochronally integrating outstanding thermal conductivity(TC)and electromagnetic interference shielding effectiveness(EMI SE)can boost the cutting-edge application of phase change materials.Here,we report a tiramisu-like composite(GMP),where the typical“crust-and-cheese”hierarchical structure is replicated by an innovative two-step bidirectional freezing assembly(BFA)and compressive densification.Hierarchical-aligned graphene array(G-GA)with ultralow thermal resistance is fabricated through 1st BFA and graphitization.During the 2nd BFA,the MXene-CNF crosslinking network with hydrogen-bond actions is used for encapsulating polyethylene glycol(PEG)onto the microlayers of the G-GA skeleton.Remarkably,the microlaminated GMP4 achieves a recorded TC of 34.05 W m^(-1) K^(-1),unprecedented EMI SE of 87.4 dB,and preferable enthalpy density of 179.4 J cm^(-3),along with leakage-free function,and eminent thermal durability.Furthermore,the GMP-loaded equipment is demonstrated for efficient microelectronics cooling and sustainable solar energy utilization.This work opens new avenues for multiscale designing multifunctional macro-composites,broadening the application prospects in advanced electronics and solar energy utilization systems. 展开更多
关键词 Phase change composite Multiscale structure construction Bidirectional freezing assembly Thermal management EMI shielding
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Circularly polarized luminescence from supramolecular assemblies based on small molecules
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作者 Xinyu Liu Xiaoyan Wang +3 位作者 Xiaotao Zhang Liqiang Li Yu Wang Wenping Hu 《Smart Molecules》 2025年第3期26-45,共20页
Circularly polarized luminescence(CPL)-active materials have a wide range of technological applications.Traditionally,creating CPL-active materials relies on the use of chiral luminophores.In contrast,supramolecular a... Circularly polarized luminescence(CPL)-active materials have a wide range of technological applications.Traditionally,creating CPL-active materials relies on the use of chiral luminophores.In contrast,supramolecular assembly introduces an innovative and promising strategy for developing CPL-active materials not only from chiral luminophores but also from achiral species.This approach significantly enriches the diversity of CPL-active materials.It also offers an effective means to optimize the performance of CPL-active materials,such as enhancing the asymmetry factor|glum|.Compared to polymers,the assembly of small molecules is generally easier to control.This review systematically summarizes the recent progress and developments in CPL from small-molecule assemblies,particularly focusing on differences,merits,and demerits of three typical assembly modes.The aim is to provide valuable insights for the future development of chiroptical materials. 展开更多
关键词 chiral supramolecular assemblies chiroptical materials circularly polarized luminescence organic small molecules supramolecular chirality
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Outbreaks of Ulva prolifera green tides reduce the network complexity and stability of cooccurring planktonic microbial communities
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作者 Honglei Zhang Hui He +8 位作者 Feilong Liu Can Wang Kaiyue Lian Chuyu Zhang Yi Li Bo Wang Andrew McMinn Hualong Wang Min Wang 《Journal of Environmental Sciences》 2025年第8期15-30,共16页
Ulva prolifera green tides are becoming aworldwide environmental problem,especially in the Yellow Sea,China.However,the effects of the occurrence of U.prolifera green tides on the community organization and stability ... Ulva prolifera green tides are becoming aworldwide environmental problem,especially in the Yellow Sea,China.However,the effects of the occurrence of U.prolifera green tides on the community organization and stability of surrounding microbiomes have still not been de-termined.Here,the prokaryotic microbial community network stability and assembly char-acteristics were systematically analyzed and compared between the green tide and non-green tide periods.U.prolifera blooms weaken the community complexity and robustness of surrounding microbiomes,increasing fragmentation and decreasing diversity.Bacteria and archaea exhibited distinct community distributions and assembly patterns under the influ-ence of green tides,and bacterial communities were more sensitive to outbreaks of green tides.The bacterial communities exhibited a greater niche breadth and a lower phyloge-netic distance during the occurrence of U.prolifera green tides compared to those during the non-green tide period while archaeal communities remained unchanged,suggesting that the bacterial communities underwent stronger homogeneous selection and more sensitive to green tide blooms than the archaeal communities.Piecewise structural equation model analysis revealed that the different responses of major prokaryotic microbial groups,such as Cyanobacteria,to environmental variables during green tides,were influenced by the variations in pH and nitrate during green tides and correlated with the salinity gradient during the non-green tide period.This study elucidates the response of the adaptability,associations,and stability of surrounding microbiomes to outbreaks of U.prolifera green tides. 展开更多
关键词 Ulva prolifera green tide Prokaryotic microbial communities Assembly process Community complexity Cooccurrence stability
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Advances in human umbilical cord mesenchymal stem cells-derived extracellular vesicles and biomaterial assemblies for endometrial injury treatment
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作者 Wan-Yu Zhang Han-Bi Wang Cheng-Yan Deng 《World Journal of Stem Cells》 2025年第1期6-21,共16页
Endometrial injury caused by repeated uterine procedures,infections,inflammation,or uterine artery dysfunction can deplete endometrial stem/progenitor cells and impair regeneration,thereby diminishing endometrial rece... Endometrial injury caused by repeated uterine procedures,infections,inflammation,or uterine artery dysfunction can deplete endometrial stem/progenitor cells and impair regeneration,thereby diminishing endometrial receptivity and evidently lowering the live birth,clinical pregnancy,and embryo implantation rates.Currently,safe and effective clinical treatment methods or gene-targeted therapies are unavailable,especially for severe endometrial injury.Umbilical cord mesenchymal stem cells and their extracellular vesicles are characterized by their simple collection,rapid proliferation,low immunogenicity,and tumorigenicity,along with their involvement in regulating angiogenesis,immune response,cell apoptosis and proliferation,inflammatory response,and fibrosis,Therefore,these cells and vesicles hold broad potential for application in endometrial repair.This article reviewed recent research on human umbilical cord mesenchymal stem cells as well as their extracellular vesicles in repairing endometrial injury. 展开更多
关键词 Endometrial injury Umbilical cord mesenchymal stem cells Extracellular vesicles MicroRNA Biomaterial assemblies Regenerative repair
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Long-term conservation tillage changes the diversity, assembly and network stability of soil diazotrophic community
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作者 Ling MA Guixiang ZHOU +6 位作者 Jiabao ZHANG Zhongjun JIA Hongtao ZOU Lin CHEN Congzhi ZHANG Donghao MA Changdong HAN 《Pedosphere》 2025年第2期299-311,共13页
Diazotrophs make important contributions to nitrogen(N) inputs in agricultural ecosystems. However, strong evidence of the effects of conservation tillage(CT) on the coexistence and assembly of soil diazotrophic commu... Diazotrophs make important contributions to nitrogen(N) inputs in agricultural ecosystems. However, strong evidence of the effects of conservation tillage(CT) on the coexistence and assembly of soil diazotrophic community and related mechanisms is lacking. Here, a long-term experiment was conducted to study the impacts of CT on the coexistence and assembly patterns of soil diazotrophic community in Lishu County, Jilin Province, North China. Compared to traditional tillage(control, CK), CT significantly reduced both the N fixation rate in top 0–10 cm soil and the alpha diversity of diazotrophic community while increasing the density of diazotrophic and overall bacterial communities. Conservation tillage also reduced the competitive relationships within the diazotrophic community and enhanced network stability. Furthermore, diazotroph assembly was dominated by deterministic processes(relative influence =68.63%) under CK and stochastic processes(relative influence = 58.82%) under CT. Soil depth and total N(TN) were identified as crucial predictors shaping the assembly processes of diazotrophic community under different tillage practices. The relative influence of stochastic processes on diazotrophic community under CT varied more significantly with increasing soil depth. Overall, tillage practice and soil depth had significant influences on the coexistence and assembly processes of soil diazotrophic community. Moreover, long-term CT may impact the selection of N fixation agents and the specific taxa associated with N fixers. Our results indicated that in CT systems, relatively sufficient nutrient availability led to a reduction in interspecies competition, an increase in network stability, and a greater influence of stochastic processes on community assembly. These findings may help us better understand biological N fixation in sustainable agricultural systems. 展开更多
关键词 alpha diversity biological nitrogen fixation community assembly deterministic processes nitrogen fixation rate soil diazotroph stochastic processes
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In-situ and operando characterizations in membrane electrode assemblies:Resolving dynamic interfaces and degradation pathways in CO_(2)electrocatalysis
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作者 Jiachen Wu Pengfei Liu Huagui Yang 《Chinese Journal of Catalysis》 2025年第12期1-8,共8页
Membrane electrode assemblies(MEAs)represent the preeminent configuration for industrial-scale CO_(2)electrolysis,yet their dynamic interfaces and degradation pathways remain inadequately resolved.This perspective hig... Membrane electrode assemblies(MEAs)represent the preeminent configuration for industrial-scale CO_(2)electrolysis,yet their dynamic interfaces and degradation pathways remain inadequately resolved.This perspective highlights how advanced operando characterization techniques-synchrotron X-ray spectroscopy,spatially resolved X-ray fluorescence,vibrational spectroscopy,electrochemical diagnostics et al.-decipher atomic-scale catalyst evolution,transient ion/water fluxes,and extreme interfacial microenvironments under industrial current densities.These methodologies reveal critical degradation mechanisms,including catalyst restructuring,carbonate precipitation-driven flooding,and cation-induced pH gradients,which are inaccessible to conventional ex-situ or three-electrode analyses.Integrating multimodal characterization is paramount to correlate transient interfacial chemistry with system-level performance,guiding the rational design of durable,high-selectivity MEAs for scalable CO_(2)conversion. 展开更多
关键词 Operando characterization Membrane electrode assemblies Electrocatalytic CO_(2)reduction Interfacial dynamics Degradation pathways
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A Knowledge Push Method of Complex Product Assembly Process Design Based on Distillation Model-Based Dynamically Enhanced Graph and Bayesian Network
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作者 Fengque Pei Yaojie Lin +2 位作者 Jianhua Liu Cunbo Zhuang Sikuan Zhai 《Chinese Journal of Mechanical Engineering》 2025年第6期117-134,共18页
Under the paradigm of Industry 5.0,intelligent manufacturing transcends mere efficiency enhancement by emphasizing human-machine collaboration,where human expertise plays a central role in assembly processes.Despite a... Under the paradigm of Industry 5.0,intelligent manufacturing transcends mere efficiency enhancement by emphasizing human-machine collaboration,where human expertise plays a central role in assembly processes.Despite advancements in intelligent and digital technologies,assembly process design still heavily relies on manual knowledge reuse,and inefficiencies and inconsistent quality in process documentation are caused.To address the aforementioned issues,this paper proposes a knowledge push method of complex product assembly process design based on distillation model-based dynamically enhanced graph and Bayesian network.First,an initial knowledge graph is constructed using a BERT-BiLSTM-CRF model trained with integrated human expertise and a fine-tuned large language model.Then,a confidence-based dynamic weighted fusion strategy is employed to achieve dynamic incremental construction of the knowledge graph with low resource consumption.Subsequently,a Bayesian network model is constructed based on the relationships between assembly components,assembly features,and operations.Bayesian network reasoning is used to push assembly process knowledge under different design requirements.Finally,the feasibility of the Bayesian network construction method and the effectiveness of Bayesian network reasoning are verified through a specific example,significantly improving the utilization of assembly process knowledge and the efficiency of assembly process design. 展开更多
关键词 Complex product assembly process Large language model Dynamic incremental construction of knowledge graph Bayesian network Knowledge push
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黏弹性表面活性剂(Ⅰ)——百年胶束发展史及蠕虫状胶束的发现 被引量:1
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作者 冯玉军 《日用化学工业(中英文)》 北大核心 2026年第1期8-16,7,共10页
表面活性剂的宏观性能、应用功能与其微观胶束结构密切相关。本文系统梳理了胶束概念的百年演进:从19世纪中叶的萌芽、20世纪初的理论奠基,到中后期借助先进表征技术实现的结构解析与形貌拓展,进而深入探讨了蠕虫状胶束的发现历程。该... 表面活性剂的宏观性能、应用功能与其微观胶束结构密切相关。本文系统梳理了胶束概念的百年演进:从19世纪中叶的萌芽、20世纪初的理论奠基,到中后期借助先进表征技术实现的结构解析与形貌拓展,进而深入探讨了蠕虫状胶束的发现历程。该类胶束具有独特的柔性链状结构与动态黏弹行为,被誉为“活聚合物”,其理论建立与性能调控推动了黏弹性表面活性剂在油田、医药、材料等领域的创新应用。文章旨在通过历史回顾与前沿分析,为功能表面活性剂的未来发展提供借鉴。 展开更多
关键词 黏弹性表面活性剂 胶束 蠕虫状胶束 胶体化学 自组装
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基于Profinet通信的语音播报模块在汽车变速箱装配产线上的应用研究
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作者 冯伟 齐冰洋 赵俊博 《时代汽车》 2025年第7期13-15,共3页
随着制造业自动化水平的持续提升对生产线实时监控和信息反馈的需求日益增强。为此,本文在对Profi net通信技术进行概述的同时,对汽车变速箱装配产线语音播报模块需求进行分析,随后以Profi net通信技术为基础进行语音播报模块设计,该模... 随着制造业自动化水平的持续提升对生产线实时监控和信息反馈的需求日益增强。为此,本文在对Profi net通信技术进行概述的同时,对汽车变速箱装配产线语音播报模块需求进行分析,随后以Profi net通信技术为基础进行语音播报模块设计,该模块通过协同传感器、视觉系统以及PLC,成功实现了变速箱装配生产线(工业控制领域)的语音提示功能。 展开更多
关键词 Profinet通信 语音播报 汽车变速箱装配产线
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纤维增强复合材料螺栓连接力学性能影响因素的研究进展
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作者 张永亮 张辉 +2 位作者 袁旖 王晓龙 杨旭东 《复合材料科学与工程》 北大核心 2026年第2期135-144,共10页
螺栓连接因其高效、可靠的连接性能在航空航天领域得到了广泛应用。然而,在纤维增强复合材料板上进行开孔等加工时,不可避免会产生分层缺陷、垂直度误差等问题;装配过程中,系统误差和人工误差也会导致螺栓连接件出现预紧力过大、过小或... 螺栓连接因其高效、可靠的连接性能在航空航天领域得到了广泛应用。然而,在纤维增强复合材料板上进行开孔等加工时,不可避免会产生分层缺陷、垂直度误差等问题;装配过程中,系统误差和人工误差也会导致螺栓连接件出现预紧力过大、过小或装配间隙等问题。这些因素都会显著影响螺栓连接结构的力学性能。因此,本文归纳了在螺栓连接制备和装配过程中影响纤维增强树脂基复合材料性能的四种关键因素:分层缺陷、垂直度误差、预紧力和装配间隙,系统阐述了各因素对其结构力学性能的影响与作用机理,并对纤维增强复合材料螺栓连接力学性能影响因素的未来研究发展趋势进行了展望。 展开更多
关键词 复合材料 螺栓连接 分层缺陷 垂直度误差 预紧力 装配间隙
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