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The Double-Double Effect of Lanthanide Complexes with Styrene-Acrylic Acid Copolymer
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作者 于广谦 李玉良 刘丛明 《Journal of Rare Earths》 SCIE EI CAS CSCD 1992年第2期148-150,共3页
The double-double (or tetrad) effect of low molecular lanthanide complexes has been reportedsince the effect was discovered by Fidelis and Siekierski.However,so far no description concerning thedouble-double effect of... The double-double (or tetrad) effect of low molecular lanthanide complexes has been reportedsince the effect was discovered by Fidelis and Siekierski.However,so far no description concerning thedouble-double effect of macromolecular lanthanide complexes has been published in literature.We have been successful in preparing lanthanide complexes with styrene-acrylic acid copolymer,someof which exhibite high activitiest in butadiene polymerization.It was found that the complexes showedthe double-double effect as they were characterized.In the present paper,the SAAC·Ln IR spectra whichcharacterize the double-double effect have been discussed in detail. 展开更多
关键词 double-double effect Lanthanide complexes COPOLYMER
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基于Double-Double理论的机身结构优化设计
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作者 郑传祥 宋兆波 +5 位作者 俞轶宸 卢锦杰 荆磊 陈思燃 苏璐 Stephen Tsai 《高科技纤维与应用》 2025年第2期43-50,共8页
Double-Double(下称DD)理论是由斯坦福大学Stephen Tsai教授首先提出,其理论依据是给定材料的复合材料层合板的蔡氏模量为常量,与纤维的敷设角度和铺设顺序无关。利用层合板的这个特点,常用传统的层合板可以用二个角度±φ、±... Double-Double(下称DD)理论是由斯坦福大学Stephen Tsai教授首先提出,其理论依据是给定材料的复合材料层合板的蔡氏模量为常量,与纤维的敷设角度和铺设顺序无关。利用层合板的这个特点,常用传统的层合板可以用二个角度±φ、±ψ的四种组合来替代。如果根据载荷情况对φ、ψ的数值进行优化,则层合板的承载性能可以得到提高;如果采用相同的安全系数,则层数可以减少达到减重的目的。本文以机身研究对象,基于DD理论对机身进行优化设计,通过计算可以发现,相同载荷下,机身重量可以得到较大的减轻。 展开更多
关键词 double-double理论 机身 优化 设计
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Double-Double铺层复合材料C型梁变厚度减重优化 被引量:2
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作者 何靓 李尧 +4 位作者 王思源 霍玥玥 张璇 元振毅 常正平 《复合材料学报》 北大核心 2025年第10期6073-6083,共11页
碳纤维增强树脂基复合材料已经成为航空、航天等领域的重要工程材料。然而,传统复合材料的铺层设计效率低、丢层设计复杂,导致复合材料构件存在一定的设计强度冗余和结构超重。Double-Double作为一种全新的复合材料铺层方法,具有铺层设... 碳纤维增强树脂基复合材料已经成为航空、航天等领域的重要工程材料。然而,传统复合材料的铺层设计效率低、丢层设计复杂,导致复合材料构件存在一定的设计强度冗余和结构超重。Double-Double作为一种全新的复合材料铺层方法,具有铺层设计简单且丢层减重便捷的优点,已成为铺层设计发展的趋势。本文结合Double-Double铺层方法、ABAQUS参数化建模和应变能理论,对复合材料C型梁进行了减重优化设计,建立的有限元分析模型可有效地显示C型梁的弯曲受力状态。结合有限元分析和试验结果,表明Double-Double构件能够有效替代传统铺层构件,在铺层数目一致时Double-Double铺层C型梁的弯曲刚度和极限载荷分别提高了9.28%和12.34%;针对两个优化后的变厚度Double-Double铺层C型梁,其弯曲刚度和强度不仅未减小,整体质量还分别减少了12.5%和17.5%,实现了减重优化目标。 展开更多
关键词 double-double CFRP C型梁 变厚度铺层 减重优化
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Double-Double帽型加筋结构复合材料层合板铺层设计及其压缩屈曲行为
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作者 丁天赐 杜晨 彭雄奇 《复合材料学报》 北大核心 2025年第11期6215-6225,共11页
碳纤维增强复合材料结构设计上高度的灵活性决定了其结构设计优化的复杂性,如何在保证精度要求下尽量减少计算成本是当下的研究热点之一。针对航空用帽型加筋结构复合材料层合板铺层设计问题,基于层压参数理论和新提出的Double-Double... 碳纤维增强复合材料结构设计上高度的灵活性决定了其结构设计优化的复杂性,如何在保证精度要求下尽量减少计算成本是当下的研究热点之一。针对航空用帽型加筋结构复合材料层合板铺层设计问题,基于层压参数理论和新提出的Double-Double铺层方法,结合屈曲理论,建立了优化变量和优化目标之间的函数关系,对帽型加强筋和帽型加筋结构复合材料层合板承载能力进行了铺层优化设计,有效降低了寻优的计算成本。通过轴向压缩实验验证了理论模型和层压参数全局寻优能力,并对帽型加筋结构复合材料层合板轴压屈曲失稳行为进行了分析。 展开更多
关键词 帽型加筋结构 屈曲失稳 double-double铺层方法 铺层设计优化 层压参数
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蔡氏模量与Double-Double铺层设计在混杂纤维层合板中的应用
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作者 阮晨龙 贡博文 +1 位作者 王欢 彭华新 《复合材料学报》 北大核心 2025年第12期7240-7253,共14页
传统的连续纤维层合板通常由0°、45°、−45°、90°角度铺层(Quad)构成。但Quad铺层的刚度可设计空间有限,过多的排列顺序也使得铺层优化和减薄设计异常困难。Double-Double(DD)层合板基于蔡氏模量不变性,给出了传统... 传统的连续纤维层合板通常由0°、45°、−45°、90°角度铺层(Quad)构成。但Quad铺层的刚度可设计空间有限,过多的排列顺序也使得铺层优化和减薄设计异常困难。Double-Double(DD)层合板基于蔡氏模量不变性,给出了传统铺层的替代方法,有望简化铺层和结构的设计流程。目前有关DD层合板的设计方案主要考虑单一碳纤维的层合板,对于混杂层合板的研究还有待开展。为了将DD层合板的设计扩展到混杂条件下,根据蔡氏模量不变性,研究了混杂DD层合板的归一化刚度特点与铺层等效设计方法,并通过实验验证了混杂DD层合板的铺层替代可行性和在减薄设计上的优势。结果表明,混杂DD层合板的归一化刚度满足蔡氏模量混杂比例p*的混杂定律,混杂DD层合板的铺层参数V与等效设计范围受到混杂比例和纤维类型的影响。具有更高同质性的混杂DD铺层策略为重复构型[+Φ_(g)/−Ψ_(c)/+Ψ_(c)/−Φ_(g)]_(r)(拉弯一致)或对称构型[±Φ_(g)/±Ψ_(c)]_(S)(无耦合效应)。混杂碳纤维/玻璃纤维混杂铺层的拉伸性能等效实验表明,混杂DD层合板及其减薄后的构型可以实现刚度的等效替代(误差<3%),拉伸强度表现上则受到铺层构型和具体失效模式的影响(误差−15.2%~+2.1%)。显示出混杂DD层合板铺层等效的可行性,为混杂层合板的设计提供了新思路。 展开更多
关键词 double-double 蔡氏模量 混杂复合材料 层合板 拉伸性能
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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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Electronically Conductive Metal−Organic Framework With Photoelectric and Photothermal Effect as a Stable Cathode for High-Temperature Photo-Assisted Zn/Sn-Air Battery
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作者 Jiangchang Chen Chuntao Yang +2 位作者 Yao Dong Ya Han Yingjian 《Carbon Energy》 2026年第1期105-114,共10页
Rechargeable Zn/Sn-air batteries have received considerable attention as promising energy storage devices.However,the electrochemical performance of these batteries is significantly constrained by the sluggish electro... Rechargeable Zn/Sn-air batteries have received considerable attention as promising energy storage devices.However,the electrochemical performance of these batteries is significantly constrained by the sluggish electrocatalytic reaction kinetics at the cathode.The integration of light energy into Zn/Sn-air batteries is a promising strategy for enhancing their performance.However,the photothermal and photoelectric effects generate heat in the battery under prolonged solar irradiation,leading to air cathode instability.This paper presents the first design and synthesis of Ni_(2)-1,5-diamino-4,8-dihydroxyanthraquinone(Ni_(2)DDA),an electronically conductiveπ-d conjugated metal-organic framework(MOF).Ni_(2)DDA exhibits both photoelectric and photothermal effects,with an optical band gap of~1.14 eV.Under illumination,Ni_(2)DDA achieves excellent oxygen evolution reaction performance(with an overpotential of 245 mV vs.reversible hydrogen electrode at 10 mA cm^(−2))and photothermal stability.These properties result from the synergy between the photoelectric and photothermal effects of Ni_(2)DDA.Upon integration into Zn/Sn-air batteries,Ni_(2)DDA ensures excellent cycling stability under light and exhibits remarkable performance in high-temperature environments up to 80℃.This study experimentally confirms the stable operation of photo-assisted Zn/Sn-air batteries under high-temperature conditions for the first time and provides novel insights into the application of electronically conductive MOFs in photoelectrocatalysis and photothermal catalysis. 展开更多
关键词 electronically conductive MOFs high temperatures photo-assisted Zn/Sn-air batteries photoelectric effects photothermal effects
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CUDA‑based GPU‑only computation for efficient tracking simulation of single and multi‑bunch collective effects
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作者 Keon Hee Kim Eun‑San Kim 《Nuclear Science and Techniques》 2026年第1期61-79,共19页
Beam-tracking simulations have been extensively utilized in the study of collective beam instabilities in circular accelerators.Traditionally,many simulation codes have relied on central processing unit(CPU)-based met... Beam-tracking simulations have been extensively utilized in the study of collective beam instabilities in circular accelerators.Traditionally,many simulation codes have relied on central processing unit(CPU)-based methods,tracking on a single CPU core,or parallelizing the computation across multiple cores via the message passing interface(MPI).Although these approaches work well for single-bunch tracking,scaling them to multiple bunches significantly increases the computational load,which often necessitates the use of a dedicated multi-CPU cluster.To address this challenge,alternative methods leveraging General-Purpose computing on Graphics Processing Units(GPGPU)have been proposed,enabling tracking studies on a standalone desktop personal computer(PC).However,frequent CPU-GPU interactions,including data transfers and synchronization operations during tracking,can introduce communication overheads,potentially reducing the overall effectiveness of GPU-based computations.In this study,we propose a novel approach that eliminates this overhead by performing the entire tracking simulation process exclusively on the GPU,thereby enabling the simultaneous processing of all bunches and their macro-particles.Specifically,we introduce MBTRACK2-CUDA,a Compute Unified Device Architecture(CUDA)ported version of MBTRACK2,which facilitates efficient tracking of single-and multi-bunch collective effects by leveraging the full GPU-resident computation. 展开更多
关键词 Code development GPU computing Collective effects
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Chemical composition and pharmacological effects of the Forsythia suspensa
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作者 Jiayuan Wang Zixuan Che +3 位作者 Yuzheng Xiang Meng Zhang Ying Li Yu Chen 《Asian Journal of Traditional Medicines》 2026年第1期42-57,共16页
The dried fruit of Forsythia suspensa(Oleaceae),also known as Forsythia,is a traditional Chinese medicinal herb known for its heat-clearing and detoxifying properties.It is used to disperse nodules,reduce swelling,rem... The dried fruit of Forsythia suspensa(Oleaceae),also known as Forsythia,is a traditional Chinese medicinal herb known for its heat-clearing and detoxifying properties.It is used to disperse nodules,reduce swelling,remove toxins,clear heat,and alleviate wind-heat syndromes.It also has hepatoprotective,anti-inflammatory,antiviral,antibacterial,anticancer,antioxidant,antiaging,and anti-obesity effects,as well as potential therapeutic effects on Alzheimer’s disease and diabetic nephropathy.It is used to treat scrofula,mastitis,wind-heat common cold,and other ailments.The review summarizes the chemical constituents and pharmacological effects of F.suspensa,aiming to provide a scientific foundation for its future development,research,and clinical utilization. 展开更多
关键词 Forsythia suspensa pharmacological effects chemical constituents
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Anomalous Hall effect in kagome ferromagnet MgMn_(6)Sn_(6) single crystal
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作者 Zhonghua Ma Jie Du +5 位作者 Jianhua Wang Feng Zhou Jie Chen Tao Zhu Hang Li Wenhong Wang 《Chinese Physics B》 2026年第2期563-568,共6页
Kagome magnets are of growing interest due to their topological electronic structures and unconventional magnetic behavior.Here,we report on the anomalous Hall effect(AHE)in the kagome ferromagnet MgMn_(6)Sn_(6),which... Kagome magnets are of growing interest due to their topological electronic structures and unconventional magnetic behavior.Here,we report on the anomalous Hall effect(AHE)in the kagome ferromagnet MgMn_(6)Sn_(6),which has a Curie temperature of~290 K and an in-plane easy magnetization axis.Magnetotransport measurements show a positive magnetoresistance(MR)below 50 K,which becomes negative at higher temperatures.An intrinsic anomalous Hall conductivity of 114 S·cm^(-1)is observed in MgMn_(6)Sn_(6) single crystals,consistent with ab initio calculations.Moreover,theoretical predictions indicate that shifting the Fermi level(EF)upward by~70 meV could enhance the AHE to~528 S·cm^(-1).These results position MgMn_(6)Sn_(6) as a promising and tunable platform for exploring topological magnetism and related electronic phenomena. 展开更多
关键词 MAGNETORESISTANCE kagome ferromagnet anomalous Hall effect
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Anomalous Hall effect and Lifshitz transition in Fe_(3)Sn_(2)nanosheets
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作者 Xue Yang Jijian Liu +14 位作者 Xinyi Zheng Lei Xu Lihong Hu Sicheng Zhou Siyuan Zhou Ximing Zhang Bingbing Tong Jie Shen Zhaozheng Lyu Xiunian Jing Fanming Qu Peiling Li Jiadong Zhou Guangtong Liu Li Lü 《Chinese Physics B》 2026年第1期287-293,共7页
Fe_(3)Sn_(2),a ferromagnetic metal with a kagome lattice,serves as an ideal platform for exploring topological electronic states and Berry curvature due to its unique band structure.However,systematic reports on the t... Fe_(3)Sn_(2),a ferromagnetic metal with a kagome lattice,serves as an ideal platform for exploring topological electronic states and Berry curvature due to its unique band structure.However,systematic reports on the transport properties of Fe_(3)Sn_(2)nanosheets remain scarce.We present temperature-dependent transport property measurements of Fe_(3)Sn_(2)nanosheets synthesized via chemical vapor deposition on Si/SiO_(2)substrates.The samples exhibit a robust anomalous Hall effect from 40 K to 300 K,along with a magnetoresistance sign reversal at 40 K at high magnetic fields,indicating a spin reorientation from in-plane to out-of-plane.Notably,a sharp crossover in the dominant transport contribution from electrons to holes near 200 K is observed,accompanied by distinct anomalous Hall behaviors in the two regimes,indicating a temperature-induced Lifshitz transition within the multi-band system.This divergence is potentially linked to a topological reconstruction of the Fermi surface across the transition.Our findings highlight the tunability of topological transport in two-dimensional kagome magnets and provide new insights into the interplay between band topology,dimensionality and magnetic order. 展开更多
关键词 kagome materials anomalous Hall effect FERROMAGNETISM Lifshitz transition
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Matrix effect of hydroxycinnamic acids on chromatic properties and phenolic profile of Cabernet Sauvignon dry red wine
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作者 Lulu Wu Yu Zhang +5 位作者 Mario Prejanò Tiziana Marino Nino Russo Guojie Jin Yongsheng Tao Yunkui Li 《Journal of Integrative Agriculture》 2026年第1期339-351,共13页
The effect of adding hydroxycinnamic acids(caffeic acid,sinapic acid,p-coumaric acid and chlorogenic acid)in Cabernet Sauvignon dry red wine before and after fermentation was investigated,taking into account the color... The effect of adding hydroxycinnamic acids(caffeic acid,sinapic acid,p-coumaric acid and chlorogenic acid)in Cabernet Sauvignon dry red wine before and after fermentation was investigated,taking into account the color parameters,anthocyanin content,and overall polyphenol levels in the wine samples.The copigmentation effect of malvidin-3-Oglucoside and sinapic acid was further explored in model solution and through theoretical calculations.The results indicated that the addition of hydroxycinnamic acids significantly enhanced the wine's color with sinapic acid(before the fermentation)showing the most pronounced color protection effect.Compared to control samples,the addition of hydroxycinnamic acids resulted in a 36%increase in total phenolic content and a 28% increase in total anthocyanin content.Thermodynamic analysis revealed that the interaction between sinapic acid and malvidin-3-O-glucoside was spontaneous and exothermic.Theoretical studies identified hydrogen bonding(HB)and dispersion forces as the main primary stabilizing forces,with the carboxyl group of sinapic acid playing a critical role while the anthocyanin backbone also influenced the interaction. 展开更多
关键词 matrix effect dry red wine POLYPHENOL hydroxycinnamic acids anthocyanins
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Study on pollutant reduction effect and environmental benefits of ultra-low emission retrofit of iron and steel sintering process:A case study of a steel group in Gansu province
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作者 Yuhao Zhang Peiqiang Zhao +5 位作者 Mingli Li Xinglin Zhang Zewei Liu Dahai Yan Chao Chen Wei Fang 《Chinese Journal of Chemical Engineering》 2026年第1期220-229,共10页
Iron and steel industry is one of the main sources of air pollution emissions in China.The sintering process is an important link in the blast furnace ironmaking process,but it is also accompanied by a large number of... Iron and steel industry is one of the main sources of air pollution emissions in China.The sintering process is an important link in the blast furnace ironmaking process,but it is also accompanied by a large number of pollutants.Under the background of ultra-low emissions,iron and steel enterprises urgently need to upgrade their existing processes to address the existing process in practical application problems.In this study,a steel group in Gansu Province was taken as an example.By comparing and analyzing the pollutant emission characteristics before and after the ultra-low emission retrofit,the collaborative control effect of the combined process on SO_(2),NO_(x),particulate matter,and dioxins after the new retrofit was systematically evaluated.The results show that after the retrofit,the concentrations of particulate matter,SO_(2) and NO_(x) have dropped to near-zero levels,and the dioxin removal efficiency has reached 98.87%,with all indicators being better than the national ultra-low emission standards.The study confirms that the optimal combination of multi-pollutant collaborative treatment technologies is the key to achieving efficient emission reduction,among which selective catalytic reduction technology has a particularly significant synergistic removal effect on NO_(x) and dioxins.This study provides an important technical reference and practical basis for the ultra-low emission retrofit of the steel industry,and has important guiding significance for promoting the green retrofit of the industry.Its ultra-low emission retrofit is of great significance for achieving green and low-carbon development. 展开更多
关键词 Ultra-low emission Collaborative governance Sintering process Emission reduction effect
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Synergistic antibacterial effect and mechanism of benzalkonium chloride and polymyxin B against Pseudomonas aeruginosa
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作者 Caihong Wang Jiaxin Zhang +3 位作者 Tong Li Jingwei Wang Dan Xu Qiao Ma 《Journal of Environmental Sciences》 2026年第1期555-564,共10页
Benzalkonium chloride(BAC)is widely employed as a broad-spectrum biocide and has emerged as a significant environmental pollutant.Polymyxin B(PB)serves as the last-line defense for the treatment of Gram-negative patho... Benzalkonium chloride(BAC)is widely employed as a broad-spectrum biocide and has emerged as a significant environmental pollutant.Polymyxin B(PB)serves as the last-line defense for the treatment of Gram-negative pathogens.Previous studies reported that BAC-adapted Pseudomonas aeruginosa increased the tolerance to PB.Herein,we present the novel finding that the combination of BAC and PB exhibited synergistic antibacterial effects against P.aeruginosa.Time-killing assay demonstrated a significant reduction in bacterial cell viability.Scanning electron microscopy,zeta potential analysis,hydrophobicity measurements,and fluorescence probe analyses collectively revealed severe disruption of the cell envelope and membrane potential induced by the combination of BAC and PB.Transcriptomic analysis revealed that the BAC-PB combination notably downreg-ulated the expression of genes involved in lipid A modification and cell envelope production,including phoPQ,pmrAB,bamABCDE,lptABCDEG,lolB,yidC,and murJ.Additionally,the combination group exhibited augmented production of reactive oxygen species and diminished ATP synthesis.The expression of the genes associated with substance metabolism and energy generation was significantly impeded.This study provides significant implica-tions for the interactions of biocides and antibiotics on Gram-negative pathogens,while also addressing antibiotic resistance and developing the external treatment strategy for Pseudomonas-infected wounds and burns. 展开更多
关键词 Pseudomonas aeruginosa Benzalkonium chloride Polymyxin B Synergistic effect Membrane disruption
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Effects of Ecological Ditch and Wetland in Reducing Farmland Drainage Pollutants in Hetao Irrigation District
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作者 Zhen HU Qiong LIAO +4 位作者 Xu LI Wei QIAO Xiang ZENG Yongbing HUANG Wei REN 《Asian Agricultural Research》 2026年第1期25-32,共8页
[Objectives]To explore the control mode of farmland drainage pollutants and investigate the effects of ecological ditch and wetland on reducing farmland drainage pollutants in Hetao Irrigation District.[Methods]Based ... [Objectives]To explore the control mode of farmland drainage pollutants and investigate the effects of ecological ditch and wetland on reducing farmland drainage pollutants in Hetao Irrigation District.[Methods]Based on the demonstration construction project of the ecological ditch-constructed wetland system in the Hetao Irrigation District,an experimental study was conducted from July to September 2023 to investigate the interception and purification effects of ecological ditches,constructed wetlands,and the combined ecological ditch-constructed wetland system on farmland drainage pollutants.Key water quality parameters measured included total nitrogen(TN)concentration and total phosphorus(TP)concentration.[Results]Different treatment modes of ecological ditches and constructed wetlands have a certain removal effect on nitrogen and phosphorus pollutants in water bodies.The ecological ditches treated with Astragalus laxmannii,Melilotus officinalis,Medicago sativa,bio-ball substrate,and bio-sheet substrate showed reduction efficiencies for TN and TP of 21.09% and 23.84%,12.06% and 26.67%,20.08% and 34.15%,23.65% and 20.56%,and 19.92% and 25.83%,respectively.The emergent plant area showed reduction efficiencies of 24.28%for TN and 17.89%for TP,while the submerged plant area achieved a reduction efficiency of 10.21%for both TN and TP.Among the different treatment modes,the ecological ditch with M.sativa performed better in TP removal,whereas the bio-ball substrate treatment mode showed higher effectiveness in TN removal.In addition,the emergent plant area exhibited better TP removal performance,while the submerged plant area was more effective in TN removal.The combined system of ecological ditch and constructed wetland achieved removal rates of 37.55% for TN and 11.47% for TP.It effectively facilitates the step-by-step interception and adsorption purification of pollutants,thereby showing significant removal and purification effects on nitrogen and phosphorus contaminants.This contributes to mitigating agricultural non-point source pollution.[Conclusions]The combined ecological ditch-constructed wetland system serves dual functions of agricultural drainage and pollutant interception and purification.It reduces the pollution load of farmland drainage on receiving water bodies to some extent and mitigates agricultural non-point source pollution.Therefore,it is a relatively suitable technology for managing agricultural non-point source pollution in the Hetao Irrigation District. 展开更多
关键词 Ecological ditch Constructed wetland POLLUTANT Purification effect Hetao Irrigation District
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An overview of the advantageous effects and underlying mechanisms of natural polysaccharides in inflammatory bowel disease
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作者 Yating Shao Bo Li +6 位作者 Yongfang Wang Chuanjie Zhou Yunlong Qiao Xinglishang He Shengqiang Tong Guiyuan Lv Suhong Chen 《Chinese Journal of Natural Medicines》 2026年第1期45-58,共14页
Inflammatory bowel disease(IBD),which includes Crohn’s disease(CD)and ulcerative colitis(UC),is a chronic inflammatory condition affecting the gastrointestinal tract.The global incidence and prevalence of IBD continu... Inflammatory bowel disease(IBD),which includes Crohn’s disease(CD)and ulcerative colitis(UC),is a chronic inflammatory condition affecting the gastrointestinal tract.The global incidence and prevalence of IBD continue to increase.While multiple clinical treatments exist,conventional therapies frequently present limitations and adverse effects.Natural polysaccharides(PSs)have emerged as a significant focus of research interest due to their therapeutic potential and applications in functional foods and health products.This review synthesizes current understanding of IBD pathophysiology and the mechanisms by which natural PSs counter IBD,including their capacity to restore immune homeostasis and intestinal barrier function,modulate gut microbiota and metabolites,reduce oxidative stress,and address irregularities in autophagy and endoplasmic reticulum stress(ERS).The review examines the structure-activity relationships of PSs demonstrating anti-IBD effects and identifies promising therapeutic products.The discussion encompasses pharmacokinetics,safety evaluations,and clinical applications of these compounds.This comprehensive review establishes a theoretical foundation for developing natural PS-based therapeutic approaches for IBD management. 展开更多
关键词 Natural polysaccharides Inflammatory bowel disease PATHOGENESIS Therapeutic effect Research progress
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Micropolar homogenization constitutive modeling and size effect analysis of lattice materials
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作者 Tingrui CHEN Fan YANG +2 位作者 Jingchun ZHANG Dong HAN Qingcheng YANG 《Applied Mathematics and Mechanics(English Edition)》 2026年第1期39-60,共22页
Lattice materials have demonstrated promising potential in engineering applications owing to their exceptional lightweight,high specific strength,and tunable mechanical properties.However,the traditional homogenizatio... Lattice materials have demonstrated promising potential in engineering applications owing to their exceptional lightweight,high specific strength,and tunable mechanical properties.However,the traditional homogenization methods based on the classical elasticity theory struggle to accurately describe the non-classical mechanical behaviors of lattice materials,especially when dealing with complex unit-cell geometries featured by non-symmetric configurations or non-single central node connections.In response to this limitation,this study establishes a generalized homogenization model based on the micropolar theory framework,employing Hill's boundary conditions to precisely predict the equivalent moduli of complex lattice materials.By introducing the independent rotational degree of freedom(DOF)characteristic of the micropolar theory,the proposed model successfully overcomes the limitation of conventional methods in accurately describing the asymmetric deformation and scale effects.We initially calculate the constitutive relations of two-dimensional(2D)cross-shaped multi-node chiral lattices and subsequently extend the method to three-dimensional(3D)lattices,successfully predicting the mechanical properties of both traditional and eccentric body-centered cubic(BCC)lattices.The theoretical model is validated through the finite element numerical verification which shows excellent consistency with the theoretical predictions.A further parametric study investigates the influence of geometric parameters,revealing the underlying size-effect mechanism.This paper provides a reliable theoretical tool for the design and property optimization of complex lattice materials. 展开更多
关键词 lattice material size effect micropolar theory homogenization method constitutive relationship
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Reshaping effects of RCEP on China’s foreign trade pattern
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作者 SONG Zhouying XU Jingya TAO Lei 《Journal of Geographical Sciences》 2026年第2期494-512,共19页
Existing studies on the Regional Comprehensive Economic Partnership(RCEP)mainly focused on institutional features,macro-economic impacts,and trade-network structures,while its geographic attributes and their implicati... Existing studies on the Regional Comprehensive Economic Partnership(RCEP)mainly focused on institutional features,macro-economic impacts,and trade-network structures,while its geographic attributes and their implications remain underexplored.Taking the RCEP as a case,this paper examines how the FTA reshapes China’s trade geography and validates these effects with an enhanced GTAP model,providing an empirical basis for advancing trade-geography theory.Key findings include:(1)RCEP significantly reduces regional trade costs.After full implementation of the agreement,the average tariffs among member countries will decrease to 40.5%of the pre-implementation level,while import and export trade facilitation levels improve by 34.3%and 29.6%,respectively.However,these improvements exhibit marked regional disparities.(2)RCEP asymmetrically promotes China’s foreign trade growth,with stronger import stimulation than export expansion,alongside significant product-specific variations.(3)The agreement reshapes China’s trade geography,driving a 7.66%increase in intra-RCEP trade while reducing extra-RCEP trade by 0.80%.(4)The restructuring of China’s trade patterns under RCEP emerges from the complex interplay of trade creation,diversion,and crowding-out effects.Accordingly,China should further harmonize regional tariff schedules,enhance trade-facilitation mechanisms,strengthen industrial competitiveness and expand multilateral partnerships. 展开更多
关键词 RCEP trade cost Chinese trade pattern reshaping effects simulation analysis
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Dynamic Adaptive Weighting of Effectiveness Assessment Indicators:Integrating G1,CRITIC and PIVW
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作者 Longyue Li Guoqing Zhang +2 位作者 Bo Cao Shuqi Wang Ye Tian 《Computers, Materials & Continua》 2026年第2期1127-1152,共26页
Modern battlefields exhibit high dynamism,where traditional static weighting methods in combat effectiveness assessment fail to capture real-time changes in indicator values,leading to limited assessment accuracy—esp... Modern battlefields exhibit high dynamism,where traditional static weighting methods in combat effectiveness assessment fail to capture real-time changes in indicator values,leading to limited assessment accuracy—especially critical in scenarios like sudden electronic warfare or degraded command,where static weights cannot reflect the operational value decay or surge of key indicators.To address this issue,this study proposes a dynamic adaptive weightingmethod for evaluation indicators based onG1-CRITIC-PIVW.First,theG1(Sequential Relationship Analysis Method)subjective weighting method—translates expert knowledge into indicator importance rankings—leverages expert knowledge to quantify the relative importance of indicators via sequential relationship ranking,while the CRITIC(Criteria Importance Through Intercriteria Correlation)objective weighting method—derives weights from data characteristics by integrating variability and inter-correlations—calculates weights by integrating indicator variability and inter-indicator correlations,ensuring data-driven objectivity.These two sets of weights are then fused using a deviation coefficient optimization model,minimizing the squared deviation from a reference weight and adjusting the fusion coefficient via Spearman’s rank correlation to resolve potential conflicts between subjective and objective judgments.Subsequently,the PIVW(Punishment-Incentive VariableWeight)theory—adapts weights to realtime indicator performance via penalty/incentive rules—is applied for dynamic adjustment.Scenario-specific penalty λ_(1) and incentive λ_(2) thresholds are set based on operational priorities and indicator volatility,penalizing indicators with values below λ_(1) and incentivizing those exceeding λ_(2) to reflect real-time indicator performance.Experimental validation was conducted using an Air Defense and Anti-Missile(ADAM)system effectiveness assessment framework,with data covering 7 indicators across 3 combat scenarios.Results show that compared to static weighting methods,the proposed method reduces MAE(Mean Absolute Error)by 15%-20% and weighted decision error rate by 84.2%,effectively reducing overestimation/underestimation of combat effectiveness in dynamic scenarios;compared to Entropy-TOPSIS,it lowers MAE by 12% while achieving a weighted Kendall’sτconsistency coefficient of 0.85,ensuring higher alignment with expert judgment.This method enhances the accuracy and scenario adaptability of effectiveness assessment,providing reliable decision support for dynamic battlefield environments. 展开更多
关键词 Adaptive weighting combined weighting model G1-CRITIC-PIVW effectiveness assessment
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Research Advances in Pharmacological Effects and Clinical Applications of Rhubarb and Its Compound Formulations in the Treatment of Sepsis
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作者 Yu CHEN Linna LU +1 位作者 Qingmin XING Lijuan SHEN 《Medicinal Plant》 2026年第1期83-91,共9页
This article reviews the research advances in traditional Chinese medicine rhubarb and its compound formulations in the treatment of sepsis,with particular emphasis on elucidating their mechanisms of action and clinic... This article reviews the research advances in traditional Chinese medicine rhubarb and its compound formulations in the treatment of sepsis,with particular emphasis on elucidating their mechanisms of action and clinical application value.Research has demonstrated that rhubarb and its compound formulations exert therapeutic effects via multiple targets and mechanisms,including anti-inflammatory actions,protection of the intestinal barrier,modulation of immune balance,inhibition of oxidative stress,and regulation of associated signaling pathways.Clinically,rhubarb has shown distinct advantages in enhancing gastrointestinal function,mitigating systemic inflammatory responses,and reducing mortality rates among patients with sepsis.These findings provide a foundational reference for the integrated prevention and treatment of sepsis through the combined use of traditional Chinese and Western medicine. 展开更多
关键词 SEPSIS RHUBARB Traditional Chinese medicine Compound formulation Pharmacological effect Clinical application
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