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液态CO_(2)相变气爆爆破孔爆能分布特征
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作者 赵宝友 季廷秀 孙建宁 《振动与冲击》 北大核心 2026年第3期271-281,共11页
液态CO_(2)致裂器喷射到爆破孔中的CO_(2)是其致裂煤岩体的唯一能量源,爆破孔爆能即CO_(2)的冲击压力分布特征对煤岩体致裂效果与机理的研究具有重要意义。采用自主研发的气爆爆能测试系统开展了现场原型致裂器气爆爆破孔爆能测试的试... 液态CO_(2)致裂器喷射到爆破孔中的CO_(2)是其致裂煤岩体的唯一能量源,爆破孔爆能即CO_(2)的冲击压力分布特征对煤岩体致裂效果与机理的研究具有重要意义。采用自主研发的气爆爆能测试系统开展了现场原型致裂器气爆爆破孔爆能测试的试验研究,考虑CO_(2)等熵流动,建立了液态CO_(2)相变气爆形成的超临界CO_(2)射流模型,并结合试验结果系统分析了气爆爆破孔爆能分布特征及其成因。结果表明:受到爆破孔限制,超临界CO_(2)射流流体产生连续脉冲式的冲击波,远离致裂器喷气口的爆能时程呈现多次间隔性瞬间升高和降低且显著非对称的倒“V”字型;宏观上爆压时程呈现快速升高和降低的三角形脉冲形式,且最高爆能分布于致裂器喷气口附近,爆压峰值可达230.000 MPa,其峰前升压和峰后降压速率均显著大于爆破孔其余位置的爆能时程特征;渗失孔即爆生裂隙周围的冲击压力还具有梯形脉冲特征,气爆爆能主要聚集在爆生裂隙周围,越靠近爆生裂隙爆能越高,爆生裂缝周围冲击压力为79.160~84.970 MPa,其中20.000 MPa以上的高压持时可维持220.000 ms左右,即液态CO_(2)相变气爆属于典型的长持时中频动载。基于试验所获得的爆能分布规律,对当前气爆工艺进行改进,提出了超临界CO_(2)点式射流冲击气爆致裂新方法。研究成果可为液态CO_(2)致裂器气爆的现场应用和理论研究提供参考。 展开更多
关键词 超临界CO_(2) 气爆 爆能 爆破孔 冲击波 等熵流
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Fe_(2)AlB_(2)的高温氧化机制及吸波性能研究
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作者 马新超 智清 +5 位作者 李威 陈毛 王海龙 张锐 张帆 范冰冰 《无机材料学报》 北大核心 2026年第1期45-54,共10页
传统吸波材料在高温条件下易失效,难以满足极端高温环境的性能需求。Fe_(2)AlB_(2)因其纳米层状结构以及优良的高温稳定性,在高温吸波领域备受关注。本研究通过湿法球磨-氩气烧结工艺制备了Fe_(2)AlB_(2)粉末,并系统研究了Fe_(2)AlB_(2... 传统吸波材料在高温条件下易失效,难以满足极端高温环境的性能需求。Fe_(2)AlB_(2)因其纳米层状结构以及优良的高温稳定性,在高温吸波领域备受关注。本研究通过湿法球磨-氩气烧结工艺制备了Fe_(2)AlB_(2)粉末,并系统研究了Fe_(2)AlB_(2)在高温下的氧化机制和吸波性能变化规律。同时,借助电磁仿真软件对其在7 GHz微波下的吸收过程进行了雷达散射截面模拟。结果表明:Fe_(2)AlB_(2)起始氧化温度为671℃,随着氧化温度的升高,其表面形成致密Al_(2)O_(3)保护膜,抗氧化性能显著增强;当氧化温度超过1000℃时,Al_(2)O_(3)膜破裂,主相转变为Fe_(2)O_(3)、Al_(4)B_(2)O_(9)以及非晶态B_(2)O_(3);在300~800℃氧化温度范围内,样品吸波性能随氧化温度升高而逐步提升,尤其在10 GHz附近,其介电损耗能力最为突出。当氧化温度升高至900℃时,在频率f=11.28 GHz下,样品的反射损耗达到-42.60 dB,相应的厚度为2.8 mm。Al_(2)O_(3)膜通过诱导“氧化膜-基体”界面极化损耗,显著提高了介电损耗效率。本研究阐明了Fe_(2)AlB_(2)在不同温度的氧化机制及其对吸波性能的影响规律,为其在高温吸波环境中的应用提供了理论基础。 展开更多
关键词 Fe_(2)AlB_(2) 抗氧化性 吸波性能 高温稳定性
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Multidimensional construction of 1T-MoS_(2)@graphene nanosheets nanocomposites for enhanced electromagnetic wave absorption 被引量:1
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作者 Jia Zhao Mukun He +3 位作者 Hua Guo Yali Zhang Hua Qiu Haoran Lai 《Journal of Materials Science & Technology》 2025年第15期35-44,共10页
The preparation of electromagnetic(EM)wave absorption materials provided with the characteristics of thin matching thickness,broad bandwidth,and mighty absorption intensity is an efficient solution to current EM pollu... The preparation of electromagnetic(EM)wave absorption materials provided with the characteristics of thin matching thickness,broad bandwidth,and mighty absorption intensity is an efficient solution to current EM pollution.Herein,Graphene nanosheets(GN)were firstly fabricated via a facile high-energy ball milling method,subsequently high-purity 1T-MoS_(2) petals were uniformly anchored on the surface of GN to prepare 1T-MoS_(2)@GN nanocomposites.Plentiful multiple reflection and scattering of EM waves in a distinctive multidimensional structure formed by GN and 1T-MoS_(2),copious polarization loss consisting of interfacial polarization loss and dipolar polarization loss severally derived from multitudinous heterointerfaces and profuse electric dipoles in 1T-MoS_(2)@GN,and mighty conduction loss originated from plentiful induced current in 1T-MoS_(2)@GN generated via the migration of massive electrons,all of which endowed 1T-MoS_(2)@GN nanocomposites with exceptional EM wave absorption performances.The minimum reflection loss(RLmin)of 1T-MoS_(2)@GN reached–50.14 dB at a thickness of only 2.10 mm,and the effective absorption bandwidth(EAB)was up to 6.72 GHz at an ultra-thin matching thickness of 1.84 mm.Moreover,the radar scattering cross section(RCS)reduction value of 36.18 dB m2 at 0°could be achieved as well,which ulteriorly validated the tremendous potential of 1T-MoS_(2)@GN nanocomposites in practical applications. 展开更多
关键词 1T-MoS_(2)@GN nanocomposites Conduction loss Polarization loss EM wave absorption
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Constructing Ti_(3)C_(2)T_(x)-MXene-based gradient woodpile structure by direct ink writing 3D printing for efficient microwave absorption 被引量:2
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作者 Changtian Zhu Pei Liu +8 位作者 Jin Chen Zixuan Ding Guohui Tang Qingqing Gao Yinxu Ni Kai Xu Zhilei Hao Gaojie Xu Fenghua Liu 《International Journal of Minerals,Metallurgy and Materials》 2025年第3期657-667,共11页
As a novel 2D material,Ti_(3)C_(2)T_(x)-MXene has become a major area of interest in the field of microwave absorption(MA).However,the MA effect of common Ti_(3)C_(2)T_(x)-MXene is not prominent and often requires com... As a novel 2D material,Ti_(3)C_(2)T_(x)-MXene has become a major area of interest in the field of microwave absorption(MA).However,the MA effect of common Ti_(3)C_(2)T_(x)-MXene is not prominent and often requires complex processes or combinations of other ma-terials to achieve enhanced performance.In this context,a kind of gradient woodpile structure using common Ti_(3)C_(2)T_(x)-MXene as MA ma-terial was designed and manufactured through direct ink writing(DIW)3D printing.The minimum reflection loss(RL_(min))of the Ti_(3)C_(2)T_(x)-MXene-based gradient woodpile structures with a thickness of less than 3 mm can reach-70 dB,showing considerable improve-ment compared with that of a completely filled structure.In addition,the effective absorption bandwidth(EAB)reaches 7.73 GHz.This study demonstrates that a Ti_(3)C_(2)T_(x)-MXene material with excellent MA performance and tunable frequency band can be successfully fab-ricated with a macroscopic structural design and through DIW 3D printing without complex material hybridization and modification,of-fering broad application prospects by reducing electromagnetic wave radiation and interference. 展开更多
关键词 Ti_(3)C_(2)T_(x)-MXene electromagnetic wave absorption macro-design impedance matching 3D printing ink
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Serum alpha-1-microglobulin as a predictor of multiple complications in type 2 diabetes mellitus patients
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作者 Li-Chao Ge Yu-Ling Zhang +5 位作者 Gui-Liang Peng Min Long Tao Jin Bin Lu Jia-Qing Shao Xing Li 《World Journal of Diabetes》 2025年第10期207-220,共14页
BACKGROUND Poor glycaemic control in patients with type 2 diabetes mellitus(T2DM)is often accompanied by multiple complications,including diabetic nephropathy(DN),diabetic retinopathy(DR),diabetic peripheral neuropath... BACKGROUND Poor glycaemic control in patients with type 2 diabetes mellitus(T2DM)is often accompanied by multiple complications,including diabetic nephropathy(DN),diabetic retinopathy(DR),diabetic peripheral neuropathy(DPN),and cardiac structural abnormality left ventricular hypertrophy(LVH).Early identification of high-risk populations for these complications and the implementation of intervention measures are crucial for improving patient outcomes.Serum alpha-1-microglobulin(α1-MG),a multifunctional protein synthesized by the liver and lymphocytes,has been considered a potential biomarker of diabetes-related diseases in recent years.AIM To investigate the associations of serumα1-MG with DN,DR,DPN,and LVH in T2DM patients and its predictive value.METHODS This retrospective study included 5045 T2DM patients.The study participants were stratified into quartiles according to their serumα1-MG levels.Multivariate logistic regression,restricted cubic spline,and explainable machine learning models were employed for risk assessment and feature importance evaluation.RESULTS Increasedα1-MG levels were observed in patients with DN,DR,DPN,and LVH(all P<0.001).Multivariate logistic regression revealed that each standard deviation increase inα1-MG was associated with an 84%increase in DN risk(OR:1.84,95%CI:1.62-2.10,P<0.001),a 17%increase in DR risk(OR:1.17,95%CI:1.07-1.28,P<0.001),a 14%increase in DPN risk(OR:1.14,95%CI:1.03-1.27,P=0.014),and a 28%increase in LVH risk(OR:1.28,95%CI:1.18-1.38,P<0.001).Subgroup analyses and machine learning confirmed the associations of elevatedα1-MG with these complications in T2DM patients.CONCLUSION Elevated serumα1-MG levels were independently associated with increased risks of DN,DR,DPN,and LVH in T2DM patients,suggesting its potential as a predictive biomarker. 展开更多
关键词 alpha-1-microglobulin Microvascular complications Cardiac complications Type 2 diabetes mellitus Machine learning models
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Leucine-rich alpha-2 glycoprotein as a superior biomarker to Creactive protein for detecting small bowel lesions in Crohn’s disease
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作者 Masashi Ohno Atsushi Nishida +4 位作者 Akinori Otsuki Yoshihiro Yokota Takayuki Imai Shigeki Bamba Osamu Inatomi 《World Journal of Gastrointestinal Endoscopy》 2025年第2期28-39,共12页
BACKGROUND Achievement of endoscopic healing(EH)is significant in the clinical practice of inflammatory bowel disease as it is correlated with improved prognosis.Existing biomarkers,including C-reactive protein(CRP),h... BACKGROUND Achievement of endoscopic healing(EH)is significant in the clinical practice of inflammatory bowel disease as it is correlated with improved prognosis.Existing biomarkers,including C-reactive protein(CRP),have relatively low accuracy for predicting EH,especially in small intestinal lesions in Crohn’s disease(CD);thus,noninvasive and more accurate biomarkers are required.Leucine-rich alpha-2 glycoprotein(LRG),a 50-kD protein,is produced under inflammatory conditions and has been reported to be useful in assessing disease activity in inflammatory bowel disease.However,the usefulness of LRG in small intestinal lesions in CD remains inconclusive.AIM To determine the usefulness of LRG for EH in small bowel lesions in CD and compare it with CRP.METHODS This study included 133 consecutive patients with CD who underwent balloonassisted enteroscopy between June 2021 and March 2024 at Shiga University of Medical Science Hospital(Otsu,Japan).We retrospectively analyzed endoscopic scores in each of the ileum and colon and four markers including LRG,CRP,albumin,and Harvey-Bradshaw index(HBI).Spearman’s rank correlation coefficient and receiver operating characteristic analysis were performed.RESULTS Either active ileal or colonic lesions exhibited significant differences in LRG,CRP,albumin,and HBI compared with EH.CRP,albumin,and HBI showed a worse correlation with endoscopic activity in the ileum than that in the colon;however,LRG did not show a worse correlation(colon,r=0.5218;ileum,r=0.5602).Receiver operating characteristic analysis revealed that LRG for EH in the ileum and colon had the same cutoff values of 12.4μg/mL.Comparing the areas under the curve of LRG and CRP for predicting EH in the ileum revealed a significantly higher areas under the curve of LRG(95%confidence interval,0.017-0.194;P=0.024),whereas the two showed no significant difference in the colon.CONCLUSION LRG is a useful biomarker in assessing the endoscopic activity of CD and is more useful than CRP in the small intestine. 展开更多
关键词 Crohn’s disease Leucine-rich alpha-2 glycoprotein Endoscopic activity ILEUM Small intestine Balloon-assisted enteroscopy
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Leucine-rich alpha-2 glycoprotein for detecting small bowel lesions in Crohn’s disease:A critical review and the path forward
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作者 Arunkumar Krishnan 《World Journal of Gastrointestinal Endoscopy》 2025年第4期74-78,共5页
The study by Ohno et al provides valuable insights into the role of leucine-rich alpha-2-glycoprotein(LRG)as a potential biomarker for identifying small bowel lesions in Crohn's disease(CD).However,several methodo... The study by Ohno et al provides valuable insights into the role of leucine-rich alpha-2-glycoprotein(LRG)as a potential biomarker for identifying small bowel lesions in Crohn's disease(CD).However,several methodological challenges hinder its immediate use in clinical practice.Notably,the current research was retrospective,lacks comparative studies with fecal calprotectin,and did not provide long-term predictive data.Further prospective studies are needed to improve the applicability of LRG.Moreover,integrating LRG with additional biomarkers and employing artificial intelligence techniques may improve its effectiveness in disease monitoring.Future research should address interobserver variability,assess LRG's cost-effectiveness,and standardize endoscopic healing definitions to ensure broader applicability.Advancing these areas is vital for establishing LRG's role in precision medicine strategies for the management of CD. 展开更多
关键词 Crohn's disease Leucine-rich alpha-2 glycoprotein Biomarkers Small bowel lesions Inflammatory bowel disease Disease monitoring Precision medicine
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2D Laplace–Fourier domain acoustic wave equation modeling with an optimal finite-difference method
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作者 Wang Jing-Yu Fan Na +4 位作者 Chen Xue-Fei Zhong Shou-Rui Li Bo-Yu Li Dan Zhao Gang 《Applied Geophysics》 2025年第1期119-131,234,共14页
Laplace–Fourier(L-F)domain finite-difference(FD)forward modeling is an important foundation for L-F domain full-waveform inversion(FWI).An optimal modeling method can improve the efficiency and accuracy of FWI.A fl e... Laplace–Fourier(L-F)domain finite-difference(FD)forward modeling is an important foundation for L-F domain full-waveform inversion(FWI).An optimal modeling method can improve the efficiency and accuracy of FWI.A fl exible FD stencil,which requires pairing and centrosymmetricity of the involved gridpoints,is used on the basis of the 2D L-F domain acoustic wave equation.The L-F domain numerical dispersion analysis is then performed by minimizing the phase error of the normalized numerical phase and attenuation propagation velocities to obtain the optimization coefficients.An optimal FD forward modeling method is finally developed for the L-F domain acoustic wave equation and applied to the traditional standard 9-point scheme and 7-and 9-point schemes,where the latter two schemes are used in discontinuous-grid FD modeling.Numerical experiments show that the optimal L-F domain FD modeling method not only has high accuracy but can also be applied to equal and unequal directional sampling intervals and discontinuous-grid FD modeling to reduce computational cost. 展开更多
关键词 Laplace-Fourier domain 2D acoustic wave equation finite difference and optimization coefficients
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CO_(2)气体分析用中波红外窄带滤光片的研制
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作者 于志强 王忠连 +6 位作者 任少鹏 娄海宇 林晓敏 黎冰 刘伟航 杨兆祥 程佳祥 《真空》 2026年第1期9-14,共6页
为提升中波红外CO_(2)气体检测的精度与灵敏度,研制了一种高性能中波红外窄带滤光片。采用蓝宝石作为基底材料,选用Ge与ZnS材料构建膜层,通过等效导纳匹配设计方法优化了膜系结构。同时,引入了敏感层拆分控制技术和比例因子差分控制薄... 为提升中波红外CO_(2)气体检测的精度与灵敏度,研制了一种高性能中波红外窄带滤光片。采用蓝宝石作为基底材料,选用Ge与ZnS材料构建膜层,通过等效导纳匹配设计方法优化了膜系结构。同时,引入了敏感层拆分控制技术和比例因子差分控制薄膜厚度,有效解决了红外波段高精度控制难题。测试结果表明:最终产品的中心波长为4269 nm,峰值透射率为89.7%,通带半宽度为126 nm,2~15μm平均截止深度达到OD2.83,该红外窄带滤光片能够有效提升气体的探测精度,为气体探测技术的进步提供了有力支撑。 展开更多
关键词 光学薄膜 中波红外 窄带滤光片 CO_(2) 气体探测器
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The design of core–shell-structured Fe@Sm_(2)Fe_(17)dual magnetic nanoparticles for high-performance electromagnetic wave absorption
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作者 Yiming Li Guifang Zheng +3 位作者 Ke Yang Xiaobai Wang Yuanfei Yang Zhenhui Ma 《Rare Metals》 2025年第9期6503-6512,共10页
The magnetic loss plays a key role in electromagnetic waves(EMW)absorption.However,the magnetic loss ability would obviously draw at high frequency,and the component lacks the dielectric loss ability,resulting in poor... The magnetic loss plays a key role in electromagnetic waves(EMW)absorption.However,the magnetic loss ability would obviously draw at high frequency,and the component lacks the dielectric loss ability,resulting in poor EMW absorption.In this work,we design a core-shell-structured Fe@Sm_(2)Fe_(17)dual magnetic nanoparticle.The 200-nm Sm_(2)Fe_(17)nanoparticles play a key role in maintaining relatively high magnetic loss ability even at high frequency.And the introduction of 3-μm Fe cubes can optimize the dielectric parameters by the interface polarization and thus enhance the impedance matching.Meanwhile,Fe cubes with easy axis vertical to six planes can absorb the EMW with different directions,leading to the enhancement of the EMW attenuation.Especially,the Fe cubes can align the moment of Sm_(2)Fe_(17)nanoparticles,which can increase exchange-coupling interaction between them to further improve the magnetic loss capacity and broaden the effective absorption bandwidth(EAB).Furthermore,the small-sized Sm_(2)Fe_(17)nanoparticles provide a rough surface,which promotes multiple reflections and scattering of the incident EMW.As a result,the optimal EMW attenuation performance with a minimum reflection loss exceeding-51.4 dB and a broadened EAB up to 6.6 GHz at 1.4 mm was achieved in Fe@Sm_(2)Fe_(17)composites with Sm/Fe of 1:12.Our work provides profound insights into developing well-coordinated magnetic-dielectric nanocomposites for EMW absorption engineering. 展开更多
关键词 Sm_(2)Fe_(17) Magnetic loss Electromagnetic waves absorption Exchange-coupling interaction
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Anchoring 1T-MoS_(2)petals on N-doped reduced graphene oxide for exceptional electromagnetic wave absorption
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作者 Jia Zhao Haoran Lai Ming Li 《International Journal of Minerals,Metallurgy and Materials》 2025年第3期619-630,共12页
The effective construction of electromagnetic(EM)wave absorption materials with thin matching thickness,broad bandwidth,and remarkable absorption is a great solution to EM pollution,which is a hot topic in current env... The effective construction of electromagnetic(EM)wave absorption materials with thin matching thickness,broad bandwidth,and remarkable absorption is a great solution to EM pollution,which is a hot topic in current environmental governance.In this study,N-doped reduced graphene oxide(N-rGO)was first prepared using a facile hydrothermal method.Then,high-purity 1T-MoS_(2)petals were homogeneously anchored to the wrinkled surface of N-rGO to fabricate 1T-MoS_(2)@N-rGO nanocomposites.The numerous electric di-poles and profuse heterointerfaces in 1T-MoS_(2)@N-rGO would induced the multiple reflection and scattering of EM waves in a distinct-ive multidimensional structure formed by two-dimensional N-rGO and 1T-MoS_(2)microspheres with plentiful thin nanosheets,remarkable conduction loss derived from the migration of massive electrons in a well-constructed conductive network formed by 1T-MoS_(2)@N-rGO,and abundant polarization loss(including dipolar polarization loss and interfacial polarization loss).All of these gave the 1T-MoS_(2)@N-rGO nanocomposites superior EM wave absorption performances.The effective absorption bandwidth of 1T-MoS_(2)@N-rGO reached 6.48 GHz with a relatively thin matching thickness of 1.84 mm,and a minimum reflection loss of-52.24 dB was achieved at 3.84 mm.Additionally,the radar scattering cross-section reduction value of 1T-MoS_(2)@N-rGO was up to 35.42 dB·m^(2) at 0°,which further verified the huge potential of our fabricated 1T-MoS_(2)@N-rGO nanocomposites in practical applications. 展开更多
关键词 1T-MoS_(2)@N-rGO nanocomposites conduction loss polarization loss ultrathin matching thickness electromagnetic wave absorption
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Catalytically tuned Bi_(2)Fe_(4)O_(9)-polypyrrole heterostructures:multifunctional electromagnetic wave absorbers with enhanced stealth and thermal camouflage
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作者 Sheng-Xiang Xiong Li-Juan Cai +5 位作者 Yang Zhang Yu Ma Di Lan Gang Chen Cheng-Jun Dong Hong-Tao Guan 《Rare Metals》 2025年第10期7720-7737,共18页
The rational design of composition and microstructure is a proven strategy for developing multifunctional high-performance electromagnetic wave(EMW)absorbers.In this study,a sandwich-structured multilayer nanoplate-li... The rational design of composition and microstructure is a proven strategy for developing multifunctional high-performance electromagnetic wave(EMW)absorbers.In this study,a sandwich-structured multilayer nanoplate-like Bi_(2)Fe_(4)O_(9)@Polypyrrole(BFO@PPy)heterostructure was successfully designed and fabricated using an efficient microwave hydrothermal method and an in situ polymerization process.Specifically,Bi_(2)Fe_(4)O_(9)enhances the chemical activity of ammonium persulfate,which in turn initiates the polymerization of pyrrole monomers,resulting in the formation of BFO@PPy heterostructures.The thickness of the PPy coating layer in the BFO@PPy composite can be precisely controlled at the nanoscale,optimizing electromagnetic parameters,conduction losses and interface polarization loss.The fabricated BFO@PPy composite achieves a minimum reflection loss(RL_(min))of-57.8 dB at a thickness of 2.5 mm and an effective absorption bandwidth(EAB)of 6.96 GHz.Furthermore,the EMW absorption performance and mechanism were systematically validated through theoretical calculations,radar cross-sectional simulations(RCS),and first-principles analysis.Notably,the RCS simulation of a 1:1 scale F-22 Raptor fighter model provides a realistic evaluation of the composite's EMW absorption potential in military applications.The efficient fabrication method and superior electromagnetic absorption performance make BFO@PPy a promising candidate for use in complex electromagnetic environments and military domains.Additionally,the BFO@PPy composite exhibits rapid electrothermal conversion at a low voltage(3V),achieving active infrared camouflage within a controllable temperature range,further highlighting its multifunctional properties. 展开更多
关键词 Bi_(2)Fe_(4)O_(9) POLYPYRROLE HETEROSTRUCTURES Multifunctional composites Electromagnetic wave absorption
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NONLINEAR WAVE TRANSITIONS AND THEIR MECHANISMS OF THE(2+1)-DIMENSIONAL KORTEWEG-DE VRIES-SAWADA-KOTERA-RAMANI EQUATION
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作者 Haolin WANG Shoufu TIAN Tiantian ZHANG 《Acta Mathematica Scientia》 2025年第4期1405-1437,共33页
In this work,we study wave state transitions of the(2+1)-dimensional Kortewegde Vries-Sawada-Kotera-Ramani(2KdVSKR)equation by analyzing the characteristic line and phase shift.By converting the wave parameters of the... In this work,we study wave state transitions of the(2+1)-dimensional Kortewegde Vries-Sawada-Kotera-Ramani(2KdVSKR)equation by analyzing the characteristic line and phase shift.By converting the wave parameters of the N-soliton solution into complex numbers,the breath wave solution is constructed.The lump wave solution is derived through the long wave limit method.Then,by choosing appropriate parameter values,we acquire a number of transformed nonlinear waves whose gradient relation is discussed according to the ratio of the wave parameters.Furthermore,we reveal transition mechanisms of the waves by exploring the nonlinear superposition of the solitary and periodic wave components.Subsequently,locality,oscillation properties and evolutionary phenomenon of the transformed waves are presented.And we also prove the change in the geometrical properties of the characteristic lines leads to the phenomena of wave evolution.Finally,for higher-order waves,a range of interaction models are depicted along with their evolutionary phenomena.And we demonstrate that their diversity is due to the fact that the solitary and periodic wave components produce different phase shifts caused by time evolution and collisions. 展开更多
关键词 the(2+1)-dimensional Korteweg-de Vries-Sawada-Kotera-Ramani equation characteristic line transformed nonlinear waves phase shift collision
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Dipole Polarization and Synchronous Magnetic Modulation Induced by FeN_(4)Moiety on Ti_(3)C_(2)T_(x) for Superior Electromagnetic Wave Absorption Performance
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作者 Xing Li Mang Niu +5 位作者 Chenwei Li Zhaozuo Zhang Jinming Zhang Ruoxin Sun Jie Hou Xiaoxia Wang 《Carbon Energy》 2025年第10期87-96,共10页
Polarization-dependent loss is important to the highly electromagnetic wave absorption(EWA)performance.Recently,metal–Nx moieties have been discovered to trigger polarization loss,but the physical origin and other po... Polarization-dependent loss is important to the highly electromagnetic wave absorption(EWA)performance.Recently,metal–Nx moieties have been discovered to trigger polarization loss,but the physical origin and other possible related loss mechanisms still need to be deeply explored.In this article,we reveal that the FeN_(4)moiety from iron phthalocyanine(FePc)can coordinate with Ti_(3)C_(2)T_(x)through Ti–OH groups,inducing dipole polarization and synchronous magnetic modulation in Fe/TiO_(2)/Ti_(3)C_(2)T_(x)composites.Interestingly,using the enhanced electric dipole moment and increased number of unpaired electrons in Fe atoms,the dipole polarization loss and possible magnetic response can be rapidly confirmed and evaluated.As a result,the minimum reflection loss(RLmin)of Fe/TiO_(2)/Ti_(3)C_(2)T_(x)composites reaches−67.12 dB at 6.72 GHz with a thickness of 3.32 mm.This study elaborates the EWA mechanism based on the atomic scale,and provides a new idea to design efficient EWA materials. 展开更多
关键词 dipole polarization electromagnetic wave FeN4 moiety magnetic property Ti_(3)C_(2)T_(x)MXen
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三角帆蚌alpha-2巨球蛋白cDNA全长的克隆及表达特征 被引量:9
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作者 施志仪 杨显祥 +1 位作者 陈晓武 李勇 《水产学报》 CAS CSCD 北大核心 2008年第4期526-532,共7页
alpha-2巨球蛋白是河蚌体内重要的天然免疫因子,参与广泛的免疫防御和调节。通过RACE法克隆了三角帆蚌α2M全长cDNA序列,提交Genbank,获得核苷酸序列登陆号:DQ993157.1。同时,采用生物信息学方法对alpha-2巨球蛋白进行了系统分析。该基... alpha-2巨球蛋白是河蚌体内重要的天然免疫因子,参与广泛的免疫防御和调节。通过RACE法克隆了三角帆蚌α2M全长cDNA序列,提交Genbank,获得核苷酸序列登陆号:DQ993157.1。同时,采用生物信息学方法对alpha-2巨球蛋白进行了系统分析。该基因cDNA全长5124bp,其中编码区4836bp,5′端非编码区35bp,3′端非编码区为253bp(含polyA尾31bp),该基因能编码1611个氨基酸,其中前23个氨基酸残基为信号肽序列,成熟蛋白分子量为177571.8u,等电点为5.49。蛋白的不稳定系数为39.53,表明该蛋白是稳定的。在此基础上,以18S作为内标,利用半定量RT-PCR法检测α2M基因在三角帆蚌不同组织和不同生理状态下的表达情况。结果表明,alpha-2巨球蛋白仅在血细胞中有表达,而在外套膜、闭壳肌、肠和性腺中没有表达。经注射大肠杆菌和嗜水气单胞菌12h后,三角帆蚌体内α2M的表达水平都有一定量的升高,证明α2M是三角帆蚌基础免疫系统中的组成部分。本研究丰富了软体动物免疫学研究内容,为三角帆蚌抗病机理提供理论资料。 展开更多
关键词 三角帆蚌 alpha-2巨球蛋白 基因表达
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Shear wave velocity prediction during CO_2-EOR and sequestration in the Gao89 well block of the Shengli Oilfield 被引量:2
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作者 李琳 马劲风 +4 位作者 王浩璠 谭明友 崔世凌 张云银 曲志鹏 《Applied Geophysics》 SCIE CSCD 2017年第3期372-380,460,共10页
Shear-wave velocity is a key parameter for calibrating monitoring time-lapse 4D seismic data during CO2-EOR (Enhanced Oil Recovery) and CO2 sequestration. However, actual S-wave velocity data are lacking, especially... Shear-wave velocity is a key parameter for calibrating monitoring time-lapse 4D seismic data during CO2-EOR (Enhanced Oil Recovery) and CO2 sequestration. However, actual S-wave velocity data are lacking, especially in 4D data for CO2 sequestration because wells are closed after the CO2 injection and seismic monitoring is continued but no well log data are acquired. When CO2 is injected into a reservoir, the pressure and saturation of the reservoirs change as well as the elastic parameters of the reservoir rocks. We propose a method to predict the S-wave velocity in reservoirs at different pressures and porosities based on the Hertz-Mindlin and Gassmann equations. Because the coordination number is unknown in the Hertz Mindlin equation, we propose a new method to predict it. Thus, we use data at different CO2 injection stages in the Gao89 well block, Shengli Oilfield. First, the sand and mud beds are separated based on the structural characteristics of the thin sand beds and then the S-wave velocity as a function of reservoir pressure and porosity is calculated. Finally, synthetic seismic seismograms are generated based on the predicted P- and S-wave velocities at different stages of CO2 injection. 展开更多
关键词 coordination number bulk modulus shear modulus Hertz-Mindlin shear wave CO2-EOR
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乳腺癌中Abi1和c-Abl及WAVE 2的表达及其相互关系 被引量:2
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作者 黄琰菁 于世英 +3 位作者 王江玲 黄念念 李健 冷彦 《中国组织化学与细胞化学杂志》 CAS CSCD 2010年第3期216-220,共5页
目的研究乳腺癌组织中Abi1、c-Abl和WAVE2蛋白的表达及其相互关系。方法应用免疫组化SP法检测66例乳腺癌组织和24例正常乳腺组织中Abi1、c-Abl和WAVE2蛋白的表达情况。结果 1.正常乳腺组织与乳腺癌组织相比,Abi1和WAVE2蛋白表达有显著... 目的研究乳腺癌组织中Abi1、c-Abl和WAVE2蛋白的表达及其相互关系。方法应用免疫组化SP法检测66例乳腺癌组织和24例正常乳腺组织中Abi1、c-Abl和WAVE2蛋白的表达情况。结果 1.正常乳腺组织与乳腺癌组织相比,Abi1和WAVE2蛋白表达有显著性差异(P<0.05),而c-Abl蛋白表达无显著性差异(P>0.05),但有定位的改变。2.Abi1强阳性率与乳腺癌的肿瘤大小、组织学分级、淋巴结转移及临床分期呈负相关性(P<0.05);与患者年龄无关(P>0.05)。c-Abl阳性率及WAVE2强阳性率均与乳腺癌的组织学分级、淋巴结转移及临床分期呈负相关性(P<0.05);与患者年龄及肿瘤大小无关(P>0.05)。3.Abi1蛋白表达与c-Abl和WAVE2蛋白表达呈正相关(P<0.05)。结论乳腺癌中Abi1低表达与预后不良有关。乳腺癌中Abi1蛋白表达的变化可影响c-Abl蛋白的定位和WAVE2蛋白的表达。推测Abi1在Abl/Abi1/WAVE2通路中具有至关重要的地位。 展开更多
关键词 乳腺肿瘤 Abi1 C-ABL wave2 免疫组化
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WAVE1、MMP-2及MMP-9在卵巢癌组织中的表达及意义 被引量:7
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作者 申丽媛 唐良萏 +1 位作者 张婧 周碎央 《第三军医大学学报》 CAS CSCD 北大核心 2013年第13期1406-1409,共4页
目的探讨WASP家族富含脯氨酸同源蛋白1(WASP-family verprolin-homologous protein 1,WAVE1)及基质金属蛋白酶-2(matrix metalloproteinases-2,MMP-2)和基质金属蛋白酶-9(MMP-9)在卵巢癌的表达及临床意义。方法采用免疫组化SABC三步法检... 目的探讨WASP家族富含脯氨酸同源蛋白1(WASP-family verprolin-homologous protein 1,WAVE1)及基质金属蛋白酶-2(matrix metalloproteinases-2,MMP-2)和基质金属蛋白酶-9(MMP-9)在卵巢癌的表达及临床意义。方法采用免疫组化SABC三步法检测47例卵巢癌、30例卵巢良性肿瘤和21例正常卵巢组织中WAVE1、MMP-2、MMP-9的表达,并对卵巢癌组织WAVE1与MMP-2、MMP-9的表达进行相关性分析。结果①WAVE1、MMP-2及MMP-9在卵巢癌中的表达均高于在正常卵巢组织及卵巢良性组织中的表达,差异有统计学意义(P<0.05);Spearman相关分析显示,WAVE1和MMP-2、MMP-9两两表达成正相关(r=0.773,r=0.664,P<0.05)。②WAVE1的表达与卵巢癌的临床分期、组织分化及Ca-125水平有关(P<0.05),与年龄、肿瘤的直径无关(P>0.05)。MMP-2、MMP-9表达与卵巢癌的临床分期有关(P<0.05),与年龄、组织分化、Ca-125水平及肿瘤直径无关(P>0.05)。结论 WAVE1和MMP-2、MMP-9在卵巢癌中呈现高表达,早期联合筛查WAVE1和MMP-2、MMP-9指标对卵巢癌病情演变和预后评估有着重要的临床意义。 展开更多
关键词 卵巢癌 wave1 基质金属蛋白酶-2 基质金属蛋白酶-9
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三角帆蚌alpha-2巨球蛋白活性测定及不同组织的表达 被引量:3
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作者 施志仪 杨显祥 《生物技术通报》 CAS CSCD 2006年第4期115-120,共6页
alpha-2巨球蛋白(alpha-2 Macroglobulin,α2M)是一种蛋白酶结合蛋白,是重要的天然免疫因子。利用α2M的作用原理,用三角帆蚌血浆保护胰蛋白酶,后用大豆蛋白酶抑制剂抑制未被保护的胰蛋白酶。利用Na-benzoyl-DL-arg-nine-p-nitroanilide... alpha-2巨球蛋白(alpha-2 Macroglobulin,α2M)是一种蛋白酶结合蛋白,是重要的天然免疫因子。利用α2M的作用原理,用三角帆蚌血浆保护胰蛋白酶,后用大豆蛋白酶抑制剂抑制未被保护的胰蛋白酶。利用Na-benzoyl-DL-arg-nine-p-nitroanilide(BAPNA)作为酶底物检测被保护的蛋白酶活性的方法,首次证明了三角帆蚌体内α2M的存在。在此基础上,克隆了α2M基因保守区受体结合区片段,进一步证明了α2M在三角帆蚌体内的存在。同时,还进行了α2M不同组织的表达检测,结果显示,α2M基因在血细胞中有表达,而在外套膜、闭壳肌、肠和性腺中没有表达。 展开更多
关键词 alpha-2巨球蛋白 α2M活性 胰蛋白酶 基因克隆 三角帆蚌
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双氢青蒿素对C2株蓝氏贾第鞭毛虫Alpha-7.3giardin基因mRNA表达水平的影响 被引量:1
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作者 余源 陈阳 +7 位作者 葛爽 王洋 李巍伟 赵丽娜 刘阿倩 林志强 高雪 田喜凤 《中国人兽共患病学报》 CAS CSCD 北大核心 2014年第7期669-672,共4页
目的观察双氢青蒿素(dihydroartemisinin,DHA)对C2株蓝氏贾第鞭毛虫(Giardia lamblia)Alpha-7.3giardin(α-贾第素)基因mRNA表达水平的影响,探讨其对蓝氏贾第鞭毛虫骨架蛋白的损伤作用。方法用双氢青蒿素浓度为100μg/mL、200μg/mL的改... 目的观察双氢青蒿素(dihydroartemisinin,DHA)对C2株蓝氏贾第鞭毛虫(Giardia lamblia)Alpha-7.3giardin(α-贾第素)基因mRNA表达水平的影响,探讨其对蓝氏贾第鞭毛虫骨架蛋白的损伤作用。方法用双氢青蒿素浓度为100μg/mL、200μg/mL的改良TYI-S-33培养基分别培养C2株蓝氏贾第鞭毛虫2h、4h、8h、12h后,以不含药物组为对照,实时荧光定量RT-PCR检测药物作用后Alpha-7.3giardin基因mRNA表达水平的变化。结果双氢青蒿素作用虫体后Alpha-7.3giardin基因mRNA表达水平明显低于对照组,二者有显著性差异。结论双氢青蒿素对C2株蓝氏贾第鞭毛虫Alpha-7.3giardin基因mRNA的表达具有明显的抑制作用,抑制效果与药物浓度和作用时间相关,提示双氢青蒿素对蓝氏贾第鞭毛虫骨架蛋白具有损伤作用。 展开更多
关键词 C2株蓝氏贾第鞭毛虫 双氢青蒿素 alpha-7.3 giardin 实时荧光定量RT—PCR
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