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Machine learning-based investigation of uplift resistance in special-shaped shield tunnels using numerical finite element modeling 被引量:1
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作者 ZHANG Wengang YE Wenyu +2 位作者 SUN Weixin LIU Zhicheng LI Zhengchuan 《土木与环境工程学报(中英文)》 北大核心 2026年第1期1-13,共13页
The uplift resistance of the soil overlying shield tunnels significantly impacts their anti-floating stability.However,research on uplift resistance concerning special-shaped shield tunnels is limited.This study combi... The uplift resistance of the soil overlying shield tunnels significantly impacts their anti-floating stability.However,research on uplift resistance concerning special-shaped shield tunnels is limited.This study combines numerical simulation with machine learning techniques to explore this issue.It presents a summary of special-shaped tunnel geometries and introduces a shape coefficient.Through the finite element software,Plaxis3D,the study simulates six key parameters—shape coefficient,burial depth ratio,tunnel’s longest horizontal length,internal friction angle,cohesion,and soil submerged bulk density—that impact uplift resistance across different conditions.Employing XGBoost and ANN methods,the feature importance of each parameter was analyzed based on the numerical simulation results.The findings demonstrate that a tunnel shape more closely resembling a circle leads to reduced uplift resistance in the overlying soil,whereas other parameters exhibit the contrary effects.Furthermore,the study reveals a diminishing trend in the feature importance of buried depth ratio,internal friction angle,tunnel longest horizontal length,cohesion,soil submerged bulk density,and shape coefficient in influencing uplift resistance. 展开更多
关键词 special-shaped tunnel shield tunnel uplift resistance numerical simulation machine learning
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Precision modification and de novo design of metabolic pathways to enhance crop nutritional quality and stress tolerance 被引量:4
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作者 Penghui Liu Jie Yang +4 位作者 Ziyue Xu Yige Han Shouchuang Wang Zoran Nikoloski Jun Yang 《The Crop Journal》 2026年第1期37-47,共11页
In light of the pressing global challenges of climate change,declining crop resilience,and hidden hunger,it is imperative to overcome the limitations of conventional crop breeding to enhance both the nutritional quali... In light of the pressing global challenges of climate change,declining crop resilience,and hidden hunger,it is imperative to overcome the limitations of conventional crop breeding to enhance both the nutritional quality and stress tolerance of crops.Synthetic metabolic engineering presents innovative strategies for the precision modification and de novo design of metabolic pathways.This approach generally encompasses three essential steps:identifying key metabolites through metabolomics,integrating multi-omics technologies to investigate the synthesis and regulation of these metabolites,and utilizing gene editing or de novo design to modify crop metabolic pathways associated with desirable agronomic traits.This review underscores the vital role of plant metabolite diversity in enhancing crop nutritional quality and stress resilience.Integrated multi-omics analyses facilitate the metabolic engineering by identifying key genes,transporters,and transcription factors that regulate metabolite biosynthesis.Precision modification strategies employ genome editing tools to reprogram endogenous metabolic networks,while de novo design reconstructs metabolic pathways through the introduction of exogenous biological elements—thereby both approaches enable the targeted enhancement of desired traits.These strategies have been effectively implemented in major food crops.However,simultaneously enhancing nutritional quality and stress resilience remains challenging due to inherent trade-offs and resource competition in distinct metabolic pathways within plants.Future research should integrate AI-driven predictive models with multi-omics datasets to decipher dynamic metabolic homeostasis and engineer climate-smart crops that maximize yield while preserving quality and environmental adaptability. 展开更多
关键词 Nutrient biofortification Stress resistance Multi-omics Synthetic metabolic engineering
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Developing eco-friendly,pest-resistant cotton by a heterologous multi-gene transformation system for caffeine synthesis 被引量:2
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作者 Yibo Fan Yingchao Tang +11 位作者 Yuanmei Miao Yanchang Zhao Lu Yu Peng Han Xiangqian Zhu Tingwan Li Guanying Wang Zhongping Xu Lu Long Wei Gao Lisong Hu Shuangxia Jin 《The Crop Journal》 2026年第1期166-175,共10页
Cotton production faces significant challenges from insect pests,with chemical pesticide use becoming increasingly limited by resistance and environmental concerns.This study explores the potential use of caffeine,a n... Cotton production faces significant challenges from insect pests,with chemical pesticide use becoming increasingly limited by resistance and environmental concerns.This study explores the potential use of caffeine,a natural plant alkaloid,as an environmentally friendly insect resistance strategy in cotton.Exogenous caffeine application demonstrated potent insecticidal effects against cotton bollworm(Helicoverpa armigera)larvae,with concentrations≥2 mg mL−1 causing near-complete feeding cessation and up to 70%larval mortality.Building on this,we engineered transgenic cotton(Gossypium hirsutum cv.Jin668)for heterologous caffeine biosynthesis by introducing three key N-methyltransferase genes(CaXMT1,CaMXMT1,CaDXMT1)by multiple gene transformation.Transgenic lines expressing all three genes showed remarkable caffeine accumulation(up to 3.59 mg g−1 dry weight),whereas two-gene combinations exhibited wild-type-level production.Feeding preference assays revealed that caffeine-enriched cotton strongly deterred feeding by H.armigera.Non-choice feeding trials demonstrated reduced leaf consumption and reduced larval growth in H.armigera fed on caffeine-producing cotton.The study highlights the effectiveness of synthetic biology approaches using the TGSII-UNiE multigene stacking system,despite challenges in transgene stability.This work advances plant-derived insect resistance research and provides a sustainable framework for reducing chemical pesticide reliance in cotton production,while underscoring unique potential of cotton as a synthetic biology platform for secondary metabolite engineering. 展开更多
关键词 Synthetic biology ALKALOIDS Pest resistance BIOPESTICIDE Secondary metabolite
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Natural and artificial evolution of acetolactate synthase for crop breeding 被引量:2
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作者 Wenbo Pan Yaoyao Zhu +4 位作者 Pingdong Li Zhiqiang Li Chunjue Xu Man Jin Xiaoyan Tang 《The Crop Journal》 2026年第1期95-106,共12页
Acetolactate synthase(ALS)-targeting herbicides are among the most widely used weed-control chemicals globally.Mutations in the ALS gene can confer herbicide resistance in crops,thereby allowing selective elimination ... Acetolactate synthase(ALS)-targeting herbicides are among the most widely used weed-control chemicals globally.Mutations in the ALS gene can confer herbicide resistance in crops,thereby allowing selective elimination of weeds without harming crops.Herbicide-resistant ALS alleles were initially discovered in weeds and subsequently developed through artificial mutagenesis techniques.With the advancement of CRISPR/Cas technologies,various genome-editing tools are now available to introduce these resistant alleles,as well as novel variants,into diverse crop species.Moreover,emerging methodologies,such as directed evolution,enable the generation and screening of large populations of random ALS mutants.Consequently,ALS has become one of the most extensively targeted genes in plant gene evolution.This paper provides a comprehensive overview of both conventional and recently developed strategies for ALS evolution,with particular emphasis on CRISPR/Cas-based genome editing and directed evolution.Future perspectives on technological application are also discussed.By advancing our understanding of herbicide-resistant ALS allele development for crop improvement,these methodologies may also pave the way for their application to the evolution of other agronomically important genes. 展开更多
关键词 Herbicide resistance Acetolactate synthase Genome editing Directed evolution
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Inverse design framework of hybrid honeycomb structure with high impact resistance based on active learning 被引量:1
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作者 Xingyu Shen Ke Yan +5 位作者 Difeng Zhu Hao Wu Shijun Luo Shaobo Qi Mengqi Yuan Xinming Qian 《Defence Technology(防务技术)》 2026年第1期407-421,共15页
In this study,an inverse design framework was established to find lightweight honeycomb structures(HCSs)with high impact resistance.The hybrid HCS,composed of re-entrant(RE)and elliptical annular re-entrant(EARE)honey... In this study,an inverse design framework was established to find lightweight honeycomb structures(HCSs)with high impact resistance.The hybrid HCS,composed of re-entrant(RE)and elliptical annular re-entrant(EARE)honeycomb cells,was created by constructing arrangement matrices to achieve structural lightweight.The machine learning(ML)framework consisted of a neural network(NN)forward regression model for predicting impact resistance and a multi-objective optimization algorithm for generating high-performance designs.The surrogate of the local design space was initially realized by establishing the NN in the small sample dataset,and the active learning strategy was used to continuously extended the local optimal design until the model converged in the global space.The results indicated that the active learning strategy significantly improved the inference capability of the NN model in unknown design domains.By guiding the iteration direction of the optimization algorithm,lightweight designs with high impact resistance were identified.The energy absorption capacity of the optimal design reached 94.98%of the EARE honeycomb,while the initial peak stress and mass decreased by 28.85%and 19.91%,respectively.Furthermore,Shapley Additive Explanations(SHAP)for global explanation of the NN indicated a strong correlation between the arrangement mode of HCS and its impact resistance.By reducing the stiffness of the cells at the top boundary of the structure,the initial impact damage sustained by the structure can be significantly improved.Overall,this study proposed a general lightweight design method for array structures under impact loads,which is beneficial for the widespread application of honeycomb-based protective structures. 展开更多
关键词 Re-entrant honeycomb Hybrid structures Inverse design Impact resistance LIGHTWEIGHT
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Linking starch particle physicochemical properties to functionality in medicinal plants:Insights from Polygonum multiflorum and Smilax glabra 被引量:1
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作者 Nan Wang Lingling Wu +2 位作者 Yaya Su Haifeng Tang Hailong Yuan 《Chinese Chemical Letters》 2026年第1期487-491,共5页
This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared ... This study investigates the properties of high-purity starches extracted from Polygonum multiflorum(PMS)and Smilax glabra(SGS).The starches were characterized by scanning electron microscopy,Fouriertransform infrared spectroscopy,X-ray diffraction,high-performance anion-exchange chromatography,and differential scanning calorimetry.Significant differences were observed in their morphological,physicochemical,and functional properties.PMS had a smaller particle size(13.68 μm),irregular polygonal shape,A-type,lower water absorption(62.67 %),and higher oil absorption(51.17 %).In contrast,SGS exhibited larger particles(31.75 μm),a nearly spherical shape,B-type,higher crystallinity(50.66 %),and greater amylose content(21.54 %),with superior thermal stability,shear resistance,and gelatinization enthalpy.SGS also contained higher resistant starch(83.28 %) and longer average chain length(20.58 %),but showed lower solubility,swelling power,light transmittance,and freeze-thaw stability.The physicochemical properties differences in crystal pattern and particle morphology between PMS and SGS lead to distinct behaviors during in vitro digestion and fermentation.These findings highlight the potential of medicinal plant starches in functional ingredients and industrial processes. 展开更多
关键词 Starch particle Physicochemical properties Starch function Resistant starch Starch extraction
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Schizophrenia:Genetics,neurological mechanisms,and therapeutic approaches 被引量:1
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作者 Debbie Xiu En Lim Shi Yun Yeo +3 位作者 Zhen You Ashley Chia Aaron Zefrin Fernandis Jimmy Lee John Jia En Chua 《Neural Regeneration Research》 2026年第3期1089-1103,共15页
Schizophrenia is a complex psychiatric disorder marked by positive and negative symptoms,leading to mood disturbances,cognitive impairments,and social withdrawal.While anti-psychotic medications remain the cornerstone... Schizophrenia is a complex psychiatric disorder marked by positive and negative symptoms,leading to mood disturbances,cognitive impairments,and social withdrawal.While anti-psychotic medications remain the cornerstone of treatment,they often fail to fully address certain symptoms.Additionally,treatment-resistant schizophrenia,affecting 30%-40%of patients,remains a substantial clinical challenge.Positive,negative symptoms and cognitive impairments have been linked to disruptions in the glutamatergic,serotonin,GABAergic,and muscarinic pathways in the brain.Recent advances using genome-wide association study and other approaches have uncovered a significant number of new schizophrenia risk genes that uncovered new,and reinforced prior,concepts on the genetic and neurological underpinnings of schizophrenia,including abnormalities in synaptic function,immune processes,and lipid metabolism.Concurrently,new therapeutics targeting different modalities,which are expected to address some of the limitations of anti-psychotic drugs currently being offered to patients,are currently being evaluated.Collectively,these efforts provide new momentum for the next phase of schizophrenia research and treatment. 展开更多
关键词 NEUROINFLAMMATION neuropsychiatric disorders neurotransmitter pathways schizophrenia risk genes treatment resistance
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Fitness and resistance mechanism of Fusarium pseudograminearum mutants resistant to fludioxonil
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作者 TIAN Yingming CHEN Yawei +3 位作者 DUAN Xiaoxin ZHENG Wei XU Jianqiang HOU Ying 《农药学学报》 北大核心 2026年第2期277-291,244,共16页
Fusarium crown rot(FCR),predominantly caused by Fusarium pseudograminearum,has been listed as a Category Ⅱ disease in six provinces of China,posing a significant threat to wheat production.The phenylpyrrole fungicide... Fusarium crown rot(FCR),predominantly caused by Fusarium pseudograminearum,has been listed as a Category Ⅱ disease in six provinces of China,posing a significant threat to wheat production.The phenylpyrrole fungicide fludioxonil is a key agent for FCR control.Previous studies indicated that resistance to fludioxonil in F.pseudograminearum is primarily associated with altered expression levels of the FpOS1 gene,which encodes a hybrid histidine kinase.However,the roles of mutations in other FpOS genes and the molecular interactions between FpOS proteins and fludioxonil remain elusive.To address these gaps,we generated 16 fludioxonil-resistant mutants with heritable resistance traits by in vitro selection of four sensitive F.pseudograminearum isolates.These mutants exhibited high resistance levels,with resistance factors(RF)ranging from 633.73 to 8617.07.Compared to their parental isolates,the resistant mutants showed significantly reduced mycelial growth rate,sporulation capacity,and pathogenicity.They were also more sensitive to ionic,osmotic,and oxidative stresses and displayed compromised cell wall and membrane integrity.Fludioxonil demonstrated no cross-resistance with tebuconazole or pydiflumetofen;however,it exhibited weak positive crossresistance to pyraclostrobin and moderate positive cross-resistance to iprodione.Fludioxonil treatment significantly promoted glycerol synthesis and inhibited deoxynivalenol(DON)production in parental isolates,whereas these regulatory effects were markedly attenuated in the resistant mutants.Mutation analysis identified mutation sites in FpOS1,FpOS4,and FpOS5 genes,with a lower mutation frequency in FpOS1 and no mutations detected in FpOS2.Molecular docking indicated that amino acid substitutions in FpOS4 and FpOS5 significantly reduced the binding affinity of fludioxonil to these target proteins.In conclusion,F.pseudograminearum poses a moderate risk of resistance to fludioxonil.Point mutations in FpOS4 and FpOS5 genes emerge as key molecular drivers of resistance,likely by diminishing the binding affinity between the fungicide and its proteins.This study clarifies the molecular basis of fludioxonil resistance in F.pseudograminearum and provides a scientific rationale for the judicious use of this fungicide in managing FCR. 展开更多
关键词 Fusarium pseudograminearum fludioxonil resistant mutant survival fitness resistant mechanism
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High Temperature Resistant Calcium-doped Silica Aerogels with Enhanced Thermal Insulation via Sol-Gel Hydrothermal Route
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作者 LI Hao QI Yuan +2 位作者 GAO Xiangdong ZHANG Xingxing WANG Jinmin 《无机材料学报》 北大核心 2026年第2期262-272,I0011,共12页
Silica aerogel has broad applications in the field of high-temperature thermal insulation due to its low density,low thermal conductivity and high stability.However,its thermal insulation performance deteriorates sign... Silica aerogel has broad applications in the field of high-temperature thermal insulation due to its low density,low thermal conductivity and high stability.However,its thermal insulation performance deteriorates significantly at elevated temperatures exceeding 600℃,primarily due to the collapse of pore structure.Meanwhile,the shielding capacity of SiO_(2) aerogel to the infrared radiation at high temperature is rather low due to the intrinsic properties of SiO_(2).Herein,a strategy for improving the high-temperature stability and infrared shielding properties of SiO_(2) aerogel via Ca doping was explored.Calcium-doped silica aerogel(CSA)powders were prepared by Sol-Gel,hydrothermal,and ambient pressure drying(APD)techniques using water glass and anhydrous calcium chloride as precursors and trimethylchlorosilane as a hydrophobic modifier.The effects of Ca/Si molar ratio in the precursor and hydrothermal conditions(temperature and pH)on the crystalline properties,microscopic morphology and pore structure of CSAs were investigated.The results show that the Ca/Si molar ratio and hydrothermal treatment have significant effects on the microstructure and heat resistance of CSAs in the temperature range of 400-1000℃.The samples sintered at 1000℃have a high specific surface area of 100.1 m^(2)/g and a pore volume of 0.8705 cm^(3)/g,indicating that the CSA has good heat resistance.One-side insulation tests at temperatures up to 600℃show that the sample with a Ca/Si molar ratio of 1.0 has the best insulation performance,with a cold surface temperature of 450℃,which is 27℃lower than that of the pure silica aerogel. 展开更多
关键词 silica aerogel calcium doping high-temperature resistance HYDROTHERMAL ambient pressure drying
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High resistance SO_(2) adsorbent of Fe-Ce-La oxides@Si-Al carrier for arsenic capture from middle-low-temperature flue gas
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作者 WEN Hangyu HOU Shuyang +2 位作者 WANG Kai ZHANG Kaihua ZHANG Kai Beijing 《燃料化学学报(中英文)》 北大核心 2026年第2期166-179,共14页
It is crucial to develop arsenic removal adsorbents with strong sulfur resistance under middle-low-temperature flue gas conditions(<400℃).In this work,five Fe-Ce-La oxides were prepared by co-precipitation method,... It is crucial to develop arsenic removal adsorbents with strong sulfur resistance under middle-low-temperature flue gas conditions(<400℃).In this work,five Fe-Ce-La oxides were prepared by co-precipitation method,and FeCeLaO/SiO_(2)-Al_(2)O_(3) composite adsorbents were prepared by coupling fly ash-based Si-Al carriers.The active components Fe-Ce-La oxides and Si-Al carriers were characterized by TPD,TG,XRF,BET and XPS,respectively.The effects of temperature,Si/Al ratio and FeCeLaO loading rate on the sulfur resistance were investigated.Results show that the SO_(2) promotes the arsenic removal of Fe_(2)O_(3),CeLaO and FeCeLaO.At 400℃,the arsenic removal efficiencies of the three oxides increase from 45.3%,72.5% and 81.3% without SO_(2) to 62.6%,80.5%and 91.0%,respectively.The SO_(2) inhibits the arsenic removal of La_(2)O_(2)CO_(3) and FeLaO,and the inhibition effect is pronounced at high temperatures.The sulfur poisoning resistance of Si-Al carriers increases with the increase of Si/Al ratio.When the Si/Al ratio is increased to 9.74,the arsenic removal efficiency in the SO_(2) environment is 13.9% higher than that in the absence of SO_(2).Introducing FeCeLaO active components is beneficial for enhancing the SO_(2) poisoning resistance of Si-Al carriers.The strong sulfur resistance of the FeCeLaO/SiO_(2)-Al_(2)O_(3) composite adsorbent results from multiple factors:protective effects of Ce on Fe,La and Al;sulfation-induced generation of Ce^(3+)and surface-adsorbed oxygen;and strong surface acidity of SiO_(2). 展开更多
关键词 arsenic removal sulfur resistance flue gas Fe-Ce-La oxides fly ash
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Preparation of Ultrafine Copper Powders by Ethanol Solvothermal Method and Properties Study
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作者 XU Yite ZHANG Xiang +6 位作者 HE Junpeng WANG Keke CAO Lei ZHU Qian LIU Baixiong LIU Jianfeng XIONG Shixian 《有色金属(中英文)》 北大核心 2026年第1期31-39,共9页
The present work provides a facile and efficient method for producing ultrafine copper powders.Ultrafine copper powders were synthesized through a solvothermal method,utilizing ethanol both as a solvent and a reducing... The present work provides a facile and efficient method for producing ultrafine copper powders.Ultrafine copper powders were synthesized through a solvothermal method,utilizing ethanol both as a solvent and a reducing agent.Specifically,by exploiting the weak reducing property of ethanol,the copper precursor is first converted to copper oxide and then further reduced to cuprous oxide and pure copper.Such a method can effectively control the morphology and particle size of the copper powder,reduce particle aggregation,and enhance oxidation resistance.It is cost-effective and produces fewer toxic by-products.Spherical copper particles with an average particle size of about 180 nm were obtained.The initial oxidation temperature is approximately 150℃,and the resulting copper powders can be stored stably under ambient conditions for at least 5 months,demonstrating excellent oxidation resistance and thermal stability. 展开更多
关键词 alcohol-solvent heat ultrafine copper powder oxidation resistance thermal stability
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Corrosion Behavior of FeCr_(x)MnAlCu High-Entropy Alloys in 3.5wt% NaCl Solution
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作者 Feng Li Zhang Xian +4 位作者 Ma Kai Zhao Yanchun Ling Yajun Liu Ruilong Fu Xuan 《稀有金属材料与工程》 北大核心 2026年第4期877-889,共13页
In this study,FeCr_(x)MnAlCu(x=0,0.5,1.0,1.5,2.0)high-entropy alloys were fabricated using vacuum arc melting,and the corrosion behavior of these alloys in 3.5wt%NaCl solution at room temperature was investigated by e... In this study,FeCr_(x)MnAlCu(x=0,0.5,1.0,1.5,2.0)high-entropy alloys were fabricated using vacuum arc melting,and the corrosion behavior of these alloys in 3.5wt%NaCl solution at room temperature was investigated by electrochemical dynamic potential polarization curves and immersion experiments.The microstructure results show that the high-entropy alloy with x=0 has a body-centered cubic phase structure,whereas the high-entropy alloys with x=0.5–2.0 have a mixed face-centered cubic+body-centered cubic dual-phase structure.The corrosion results show that the corrosion resistance of the high-entropy alloy is increased with the increase in Cr content.Among them,the high-entropy alloy with x=2.0 exhibits the optimal corrosion resistance:the highest self-corrosion potential(E_(corr)=−0.354 V vs.Ag/AgCl),the smallest self-corrosion current density(I_(corr)=1.991×10^(−6)A·cm^(−2)),and the smallest corrosion rate(0.0292 mm/a).The composite passivation film of oxides and hydroxides is formed on the surface of the corroded high-entropy alloys,and the Cr_(2)O_(3)content is increased with the increase in Cr content,which effectively improves the stability and protective properties of the passivation film. 展开更多
关键词 corrosion resistance high-entropy alloy passivation film salt solution corrosion
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Research Status and Prospects of Platinum Group Metal Coatings with High-Temperature Oxidation Resistance
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作者 Ding Chenxi Liu Zhongyu +3 位作者 Fang Zhen Wang Haoxu Lv Biao Hu Zhenfeng 《稀有金属材料与工程》 北大核心 2026年第2期333-344,共12页
Platinum group metals have high melting points,strong corrosion resistance,stable chemical properties,and low oxygen permeability in high-temperature oxygen-containing environments.As thermal protective coating materi... Platinum group metals have high melting points,strong corrosion resistance,stable chemical properties,and low oxygen permeability in high-temperature oxygen-containing environments.As thermal protective coating materials,they have gained essential applications in the aerospace field and have excellent prospects for application in frontier military fields,such as protecting hot-end components of hypersonic aircraft.This research reviewed the latest research progress of platinum group metal coatings with hightemperature oxidation resistance,including coating preparation techniques,oxidation failure,and alloying modification.The leading preparation techniques of current platinum group metal coatings were discussed,as well as the advantages and disadvantages of various existing preparation techniques.Besides,the intrinsic properties,failure forms,and failure mechanisms of coatings of single platinum group metal in high-temperature oxygen-containing environments were analyzed.On this basis,the necessity,main methods,and main achievements of alloying modification of platinum group metals were summarized.Finally,the future development of platinum group coatings with high-temperature oxidation resistance was discussed and prospected. 展开更多
关键词 platinum group metal coatings preparation technique high temperature oxidation resistance alloying modification
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In-Flight Heating Process of Cerium Oxide Powders in Radio Frequency Thermal Plasma Considering Thermal Resistance Effect
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作者 Su Yi Liu Ruizhe +3 位作者 Ahmad Hilal Zhao Peng Jin Xingyue Zhu Hailong 《稀有金属材料与工程》 北大核心 2026年第3期581-594,共14页
The in-flight heating process of cerium dioxide(CeO_(2))powders was investigated through experiments and numerical simulations.In the experiment,CeO_(2)powder(average size of 30μm)was injected into radio-frequency(RF... The in-flight heating process of cerium dioxide(CeO_(2))powders was investigated through experiments and numerical simulations.In the experiment,CeO_(2)powder(average size of 30μm)was injected into radio-frequency(RF)argon plasma,and the temperatures were measured using a DPV-2000 monitor.A model combining the electromagnetism,thermal flow,and heat transfer characteristics of powder during in-flight heating in argon plasma was proposed.The melting processes of CeO_(2)powders of different diameters,with and without thermal resistance effect,were investigated.Results show that the heating process of CeO_(2)powder particles consists of three main stages,one of which is relevant to a dimensionless parameter known as the Biot number.When the Biot value≥0.1,thermal resistance increases significantly,especially for the larger powders.The predicted temperature of the particles at the outlet(1800–2880 K)is in good agreement with the experimental result. 展开更多
关键词 RF thermal plasma thermal resistance effect heating process Biot number
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Bioinformatics and Network Pharmacology Confirmed that Red Mulberry Water Extract Can Improve Diabetes
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作者 LIU Jiaqi ZANG Yanqing 《食品工业科技》 北大核心 2026年第8期456-469,共14页
Type 2 diabetes mellitus(T2DM)was identified as the most prevalent form of diabetes.This study employed an integrated strategy combining network pharmacology,metabolomics,and experimental validation to elucidate the t... Type 2 diabetes mellitus(T2DM)was identified as the most prevalent form of diabetes.This study employed an integrated strategy combining network pharmacology,metabolomics,and experimental validation to elucidate the therapeutic mechanisms of red mulberry water extract(RMW)in T2DM.Systematic analysis identified six bioactive constituents,with four key components(cyanidin,quercetin,morin,andβ-carotene)demonstrating significant interactions with diabetes-related targets.Network pharmacology revealed these compounds modulate critical pathways including AMPK(P=2.3×10^(−5)),PI3K-Akt(P=1.8×10^(−4)),and PPAR signaling(P=3.1×10^(−3)).In diabetic mice,treatment significantly improved glycemic control(32.5%reduction in fasting glucose,P<0.01),lipid profiles(36.7%lower TG,P<0.05),antioxidant activity(2.1-fold increased SOD,P<0.05),and inflammation(42%reduced TNF-α,P<0.05).Metabolomic analysis further confirmed alterations in catecholamine and lipid metabolism pathways.These findings collectively demonstrate mulberry's multi-target therapeutic potential through synergistic regulation of glucose metabolism,lipid homeostasis,oxidative stress,and inflammatory responses in diabetes. 展开更多
关键词 MULBERRY type 2 diabetes mellitus(T2DM) network pharmacology bioactive compounds insulin resistance PPAR signaling oxidative stress
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SiO_(2)decorated wood nanocomposite with enhanced mechanical performance,flame and water resistance
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作者 Youyong Wang Xiangqian Wang +5 位作者 Beizhou Zhang Shuai Zhai Hao Li Yuanqing Li Weibin Zhu Shaoyun Fu 《Nano Materials Science》 2026年第2期307-313,共7页
Development of lightweight and strong structural material using fast-growing poplar wood is promising for green and sustainable engineering.Herein,the overall performances of fast-growing natural poplar wood(NPW)are s... Development of lightweight and strong structural material using fast-growing poplar wood is promising for green and sustainable engineering.Herein,the overall performances of fast-growing natural poplar wood(NPW)are significantly enhanced via delignification,in situ growth of SiO_(2)followed by densification.The SiO_(2)/compresseddelignified-wood(SiO_(2)/CDW)nanocomposite obtained exhibits outstanding mechanical properties including a bending strength of 395.6 MPa,a tensile strength of 253.4 MPa,and a toughness of 7.1 MJ/m^(3),which is improved by 1548%,240%and 590%,respectively compared with NPW.In addition,the ignition time and burning time of SiO_(2)/CDW nanocomposite are prolonged by 700%and 112%compared to those of NPW.Moreover,the specific wear rate of SiO_(2)/CDW is 18×10^(-6)mm^(3)/Nm,which is 72.6%lower than that of NPW.Moreover,the spring-back ratios of SiO_(2)/CDW in 95%and in water are 45.2%and 66.7%,which are lower than those of CDW(64.6%and 92.4%).The SiO_(2)/CDW nanocomposite with enhanced mechanical,flame/water retardant and wear performances are promising to meet the needs of modern engineering as green and sustainable materials. 展开更多
关键词 WOOD SiO_(2) Mechanical robustness Fire resistance Water resistance Wear resistance
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A review on enhancing properties of low carbon-containing refractories for advanced iron and steelmaking:from perspective of additives
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作者 Chun-Zhuo Feng Dong-Hai Ding +1 位作者 Guo-Qing Xiao Chang-Kun Lei 《Journal of Iron and Steel Research International》 2026年第1期412-426,共15页
The accelerated shift toward high efficiency and sustainability of the iron and steel is driving the advancement of green,low-carbon and high-quality carbon-containing refractories used for ladles.It is undoubtedly a ... The accelerated shift toward high efficiency and sustainability of the iron and steel is driving the advancement of green,low-carbon and high-quality carbon-containing refractories used for ladles.It is undoubtedly a significant challenge,since the addition of graphite enables refractories to possess superior thermal shock resistance and slag corrosion resistance.To develop low carbon-containing refractories with excellent properties,researchers over the past decades have endeavored to seek additives which can mitigate the adverse effects associated with the decrease in carbon in refractories.These additives can promote the occurrence of various mechanisms about toughening,which depends on inherent properties of additives or reacting with refractories to in situ form different ceramic phases,thereby responding the challenge of low-carbonization in refractories.The latest advances in additives used for low carbon-containing refractories from metal/alloys,oxide,non-oxide and composite powders four aspects were comprehensively overviewed in this review.Oxide additives exhibit a moderate effect on improving thermal shock resistance of refractories but show limited efficacy in improving oxidation resistance.In contrast,non-oxide additives demonstrate remarkable advantages in enhancing both oxidation and slag corrosion resistance.Composite powders combine the advantageous properties of their individual components.These additives often require combination with antioxidants such as Al,Si,or B4C not only to reduce costs but also to achieve optimal properties.Furthermore,future perspectives of these additives are discussed,with the aim of providing useful insights for the continuous progress and practical application of low carbon-containing refractories. 展开更多
关键词 ADDITIVE Low carbon-containing refractory Slag corrosion resistance Thermal shock resistance Oxidation resistance
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A Stody of the Effect ot "Strenothening Body ReSiStence Method" on ASthma Attack
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作者 许得盛 沈自尹 +1 位作者 王文健 陈伟华 《Chinese Journal of Integrative Medicine》 SCIE CAS 1996年第2期86-90,共5页
In order to stody the effect of a traditional Chinese medical treating method (StrengtheningBody Resistance Method) on asthma attack, asthmatic patients of either Cold type or Heat type were dividedinto two groups and... In order to stody the effect of a traditional Chinese medical treating method (StrengtheningBody Resistance Method) on asthma attack, asthmatic patients of either Cold type or Heat type were dividedinto two groups and treated with tlie Chinese methods ' Zhibiao' I symptomatic treatments, as the controlgroup) and 'Biaoben Jianzhi' (treating both the secondary and principal aspects of a disease, as the testgroup) respectively. The results showed tliat the markedly effective rates were higher in ttie two ' BiaobenJianzhi' groups than that in the two 'Zhibiao' groups. After treatment, the changeS of one second forced ex-piratory volume (FEV1) and the peak expiratory flow of patients of the former were also greater than those otthe latter; the proportion of cells carrying human leukocyte antigen class II(HLA-DR+ cell) , the baSOphiliccoll releasing capacity I HBR) and the T coll hyperplasia resporise to specific allergens of patients of the'Biaoben Jianzhi' groiJps were all redced while those of the 'Zhibiao' groiJps chafiged little. These resultssuggested that the 'Strengthening Body Resistaiice method' played an important role in regulating immunityfor relieving asthma attack. 展开更多
关键词 ASTHMA strengthening body resistence method pulmonary fonction IMMUNOREGULATION
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Enhancement of the crack and erosion resistance of silty clay under freeze–thaw cycles:Synergistic effect of sisal fiber–fly ash
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作者 DING Jiashun LIU Huanan +4 位作者 QIU Dan ZHAI Lianghao QI Bo YU Chenglong YUE Keyu 《Journal of Mountain Science》 2026年第2期828-844,共17页
Freeze–thaw(F–T)cycle-induced cracking in silty clays poses a significant risk to engineering stability.Although the individual addition of fly ash(FA)or sisal fiber(SF)provides partial solutions,their simultaneous ... Freeze–thaw(F–T)cycle-induced cracking in silty clays poses a significant risk to engineering stability.Although the individual addition of fly ash(FA)or sisal fiber(SF)provides partial solutions,their simultaneous application may result in a synergistic effect to compensate for their respective shortcomings.In this study,the effects of SF and FA on the mechanical properties,crack resistance,water retention,and erosion resistance of improved soil were systematically investigated through unconfined compressive strength(UCS)tests,crack evolution analysis,simulated rainfall erosion tests,and microscopic characterization(laser particle size analysis and nitrogen adsorption).The results reveal that the volumetric stability of FA particles significantly inhibits cracking in soil after F–T cycles.However,FA contributes only slightly to soil strength and erosion resistance.SF,on the other hand,plays a substantial role in increasing both soil strength and erosion resistance.The synergy between FA and SF results in the simultaneous increase in crack resistance,erosion resistance,and strength.FA improves the aggregate stability during F–T cycles,whereas SF reinforces the bonds between these aggregates.A comprehensive evaluation of the improved soil during F–T cycles using the entropy weight-TOPSIS method reveal that the combination of 10%FA+18 mm SF performed the best,achieving a 246%higher composite score than the unmodified soil did.With respect to this optimal combination,compared with the unmodified soil,the SF–FA-improved soil exhibits a 30%reduction in the average crack width,a 30%reduction in the erosion rate,and a 46%increase in strength.The findings of this study provide a scientific basis for the design of soil improvement in disaster mitigation engineering in seasonally frozen soil regions. 展开更多
关键词 Freeze-thaw cycle Sisal fiber Fly ash Crack resistance Erosion resistance Synergistic effect
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Dual carbapenem-fluoroquinolone resistance in community-onset pediatric urinary tract infections:Phenotypic-genotypic integration in three cases
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作者 C Quang Ngo D Hung Tran +2 位作者 T Trung Huynh Q Nhu Nguyen H My Le 《Asian Pacific Journal of Tropical Medicine》 2026年第1期45-48,共4页
Urinary tract infections(UTIs)are among the most prevalent pediatric bacterial infections,and undertreated episodes may lead to renal scarring,hypertension,or chronic kidney disease.Multidrug-resistant(MDR)Enterobacte... Urinary tract infections(UTIs)are among the most prevalent pediatric bacterial infections,and undertreated episodes may lead to renal scarring,hypertension,or chronic kidney disease.Multidrug-resistant(MDR)Enterobacterales have been increasingly reported in children,with higher rates in Asian and Middle Eastern settings than in high-income countries[1,2]. 展开更多
关键词 phenotypic genotypic integration chronic kidney diseasemultidrug resistant mdr enterobacterales community onset pediatric urinary tract infections renal scarring urinary tract infections dual carbapenem fluoroquinolone resistance multidrug resistant enterobacterales
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