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Gradient-Guided Assembly Instruction Relocation for Adversarial Attacks Against Binary Code Similarity Detection
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作者 Ran Wei Hui Shu 《Computers, Materials & Continua》 2026年第1期1372-1394,共23页
Transformer-based models have significantly advanced binary code similarity detection(BCSD)by leveraging their semantic encoding capabilities for efficient function matching across diverse compilation settings.Althoug... Transformer-based models have significantly advanced binary code similarity detection(BCSD)by leveraging their semantic encoding capabilities for efficient function matching across diverse compilation settings.Although adversarial examples can strategically undermine the accuracy of BCSD models and protect critical code,existing techniques predominantly depend on inserting artificial instructions,which incur high computational costs and offer limited diversity of perturbations.To address these limitations,we propose AIMA,a novel gradient-guided assembly instruction relocation method.Our method decouples the detection model into tokenization,embedding,and encoding layers to enable efficient gradient computation.Since token IDs of instructions are discrete and nondifferentiable,we compute gradients in the continuous embedding space to evaluate the influence of each token.The most critical tokens are identified by calculating the L2 norm of their embedding gradients.We then establish a mapping between instructions and their corresponding tokens to aggregate token-level importance into instructionlevel significance.To maximize adversarial impact,a sliding window algorithm selects the most influential contiguous segments for relocation,ensuring optimal perturbation with minimal length.This approach efficiently locates critical code regions without expensive search operations.The selected segments are relocated outside their original function boundaries via a jump mechanism,which preserves runtime control flow and functionality while introducing“deletion”effects in the static instruction sequence.Extensive experiments show that AIMA reduces similarity scores by up to 35.8%in state-of-the-art BCSD models.When incorporated into training data,it also enhances model robustness,achieving a 5.9%improvement in AUROC. 展开更多
关键词 Assembly instruction relocation adversary attack binary code similarity detection
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基于BDD电极的实际含能材料废水中氮转化电化学处理 被引量:1
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作者 尤家军 熊鹰 +1 位作者 王兵 汪建 《含能材料》 北大核心 2025年第3期266-276,共11页
中试含能材料废水含各类高浓度含氮化合物(氨氮(NH_(3)─N)、亚硝酸盐(NO_(2)^(-))、硝酸盐(NO3-)等)和有机污染物,是一类极难降解的废水。为实现对含能材料废水中含氮化合物的高效、定向去除,采用热丝化学气相沉积(热丝化学气相沉积法(... 中试含能材料废水含各类高浓度含氮化合物(氨氮(NH_(3)─N)、亚硝酸盐(NO_(2)^(-))、硝酸盐(NO3-)等)和有机污染物,是一类极难降解的废水。为实现对含能材料废水中含氮化合物的高效、定向去除,采用热丝化学气相沉积(热丝化学气相沉积法(HFCVD))法制备的掺硼金刚石(BDD)电极对其进行电化学降解,重点研究了氯化钠和硫酸钠等电解质成分及浓度、修饰电极类型(如Cu/BDD、Ni/BD电极)及电解装置结构(单池、双池)对含氮化合物降解效果的影响。结果表明:在含能材料废水中添加0.1 M氯化钠电解质有助于提高NH3─N直接转化为氮气(N_(2))的选择性;采用Cu/BDD、Ni/BDD阴极可加速高价氮向NH_(3)─N的转化过程;双电解池结构体系下,以Cu/BDD、Ni/BDD电极为阳极可以提高NH3─N转化为N_(2)的降解速率。因此,采用金属修饰BDD电极为阳极的双电解池结构在添加0.1 M NaCl电解质情况下有望对宏量含能材料废水进行快速、高效、高选择性降解。 展开更多
关键词 掺硼金刚石(bdd)电极 含能材料废水 电化学
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基于行为级BDD与复合域优化的高吞吐量SM4架构
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作者 丁勇盛 王胜 +3 位作者 曹元 蒋昊润 董为民 陈怡逍 《计算机工程与设计》 北大核心 2025年第12期3382-3388,共7页
针对资源受限终端在高速通信场景下对大吞吐量加密处理的需求不断提高,提出了一种高吞吐量SM4核心架构。该方法在轮函数内部对S盒前后插入流水寄存器,使关键路径缩短为单个S盒延时,并结合行为级BDD技术构建新的S盒以降低逻辑面积。进一... 针对资源受限终端在高速通信场景下对大吞吐量加密处理的需求不断提高,提出了一种高吞吐量SM4核心架构。该方法在轮函数内部对S盒前后插入流水寄存器,使关键路径缩短为单个S盒延时,并结合行为级BDD技术构建新的S盒以降低逻辑面积。进一步利用矩阵预处理和延迟驱动二叉树优化复合域映射电路,得到了面积延时积较小复合域SM4S盒。实验结果表明,该架构在FPGA与ASIC上均实现了显著的吞吐量提升,其中行为级BDD S盒减少约1.33k门面积;复合域S盒在同类设计中达到当前国内最优的面积延时积。 展开更多
关键词 轻量级 高吞吐量 复合域 SM4 分组密码 S盒 bdd
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家用终端BDD装置耦合超声去除水中新污染物效能
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作者 张硕 黄超 +4 位作者 蔡颖婷 朱静怡 祝淑敏 卜令君 周石庆 《中国给水排水》 北大核心 2025年第15期75-82,共8页
新污染物广泛存在于地表水、地下水及饮用水中,现有饮用水处理工艺对其难以有效去除。为此,研究了家用终端掺硼金刚石薄膜电极装置耦合超声(BDD/US)对水中新污染物的去除性能,以敌草隆、阿特拉津(ATZ)作为目标污染物,以单独BDD电极体系... 新污染物广泛存在于地表水、地下水及饮用水中,现有饮用水处理工艺对其难以有效去除。为此,研究了家用终端掺硼金刚石薄膜电极装置耦合超声(BDD/US)对水中新污染物的去除性能,以敌草隆、阿特拉津(ATZ)作为目标污染物,以单独BDD电极体系作为对照,确定了BDD/US体系的最佳工作参数,对比了两种体系对目标污染物和总有机碳(TOC)的去除效果,并分析了降解机理和降解毒性。结果表明,US的加入提高了体系中的活性氧(ROS)水平,BDD/US体系对敌草隆和ATZ的降解率分别提高10.11%和17.94%;即使降低BDD电极体系电流,1.2 A/1.0 A BDD/US体系依旧能够达到1.5 A BDD电极体系对两种目标物的去除效果水平;敌草隆和ATZ在降解过程中急性毒性逐步降低。 展开更多
关键词 掺硼金刚石电极 超声 新污染物 活性氧 急性毒性 总有机碳
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Synergistic properties of the binary mixed system of natural green surfactants:Camellia oleifera saponin and sodium cocoyl glycinate
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作者 Yawen Li Weixin Li +3 位作者 Fenglun Zhang Shihong Ma Jianxin Jiang Liwei Zhu 《日用化学工业(中英文)》 北大核心 2025年第7期831-843,共13页
Sodium cocoyl glycinate(SCG),an environmentally friendly anionic amino acid surfactant,is widely used in daily chemical products as an upgraded alternative to traditional surfactants.In this study,crude Camellia oleif... Sodium cocoyl glycinate(SCG),an environmentally friendly anionic amino acid surfactant,is widely used in daily chemical products as an upgraded alternative to traditional surfactants.In this study,crude Camellia oleifera saponin(COS)was purified using AB-8 macroporous adsorption resin,and its composition and structure were analyzed.The effects of different mole fractions of COS(αCOS)on surface tension(γ),oil-water interfacial tension(IFT),emulsification,and foam properties of COS-SCG binary mixed systems were investigated in mixtures of SCG with purified COS.The stability ofγand foamability under diverse environmental conditions were also discussed.The results indicated that the COS-SCG system exhibited remarkable surface-active synergism.The minimum critical micelle concentration(cmc)of the mixed system was lower than that of SCG,and adding a small mole fraction of COS(1%-2%)induced a synergistic reduction ofγ.Specifically,the cmc andγwere 2.50×10-4 mol/L and 23.1 mN/m forαCOS=1%,respectively.The system exhibited exceptional IFT reduction capacity,achieving a minimum value of 1.42 mN/m atαCOS=10%.The mixed system reached a foaming volume(atαCOS=50%)and foam stability(atαCOS=75%)were 51.0 mL and 97.37%,respectively.Microscopic analysis further confirmed these outstanding foam properties.Moreover,the COS-SCG system displayed reducedγwith enhanced foaming volume under elevated temperatures(35-75℃)and salinity(0-20 g/L).However,acidic conditions and hard water compromised bothγstability and foamability. 展开更多
关键词 SAPONIN sodium cocoyl glycinate binary mixed system synergism interfacial tension foam properties
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Impact factor analysis of less developed farmers'livelihood strategies based on the binary Logit model
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作者 HE Li-Long TAN Hao-Wen +1 位作者 GUO Jin-Ting XIA Ting-Fu 《四川大学学报(自然科学版)》 北大核心 2025年第5期1265-1280,共16页
In this paper,based on the structure-behavior coupling paradigm,we propose the concept of deviation of central town to describe the geography-market distance between farmers and the central regional town.Using the sur... In this paper,based on the structure-behavior coupling paradigm,we propose the concept of deviation of central town to describe the geography-market distance between farmers and the central regional town.Using the survey data from farmers in a poverty-stricken village in Western China,the impact of deviation of central town on farmers'livelihood strategies is analyzed.The results indicate that farmers exhibit spatial heterogeneity in their livelihood strategies.Those with low deviation show a strong inclination towards working in urban areas,while those with high deviation tend to integrate into rural industries.The deviation of central town influences farmers'livelihood strategies through the information effect,which is also affected by the level of rural infrastructure and public services,labor force structure and assistance policies.The obtained results are expected to provide guidance for promoting the integration of farmers into the urban-rural economic cycle based on sustainable livelihoods and connecting poverty alleviation with rural revitalization. 展开更多
关键词 Deviation of central town Livelihood strategy binary Logit model
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BDD电极电化学氧化处理盐湖提锂高TOC蒸发母液的工艺参数研究
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作者 何志 赵聪 +6 位作者 廖正江 何劲松 肖松林 王诗潇 费飚 张潇迪 唐田 《盐湖研究》 2025年第3期64-69,共6页
以草酸/草酸盐沉淀法除杂是盐湖提锂极具发展前景的提锂工艺之一,但是因加入过量草酸/草酸盐会导致蒸发母液的总有机碳(TOC)过高进而对生产稳定性造成影响,所以需要降低TOC。以某大型化工企业的蒸发母液为原料,系统研究了硼掺杂的金刚石... 以草酸/草酸盐沉淀法除杂是盐湖提锂极具发展前景的提锂工艺之一,但是因加入过量草酸/草酸盐会导致蒸发母液的总有机碳(TOC)过高进而对生产稳定性造成影响,所以需要降低TOC。以某大型化工企业的蒸发母液为原料,系统研究了硼掺杂的金刚石(BDD)电极电化学氧化降低TOC的最佳工艺参数,提出一种经济可行的组合方案。实验结果显示,在反应温度60℃、电流密度70 mA/cm^(2)条件下,BDD电化学氧化24 h可将母液TOC从1550 mg/L降到66.8 mg/L,氧化助剂H2O2的加入对降解效果没有增益作用。基于BDD电化学氧化在8 h内具有可观的TOC去除效果,为了进一步优化所需能耗,提出“XDA-1型大孔树脂吸附(2 BV/h,25℃,动态吸附)+BDD电化学氧化4 h(60℃,70 mA/cm^(2))+C1型活性炭(6 h,25℃,静态吸附)”的方案,可将母液TOC值从1550 mg/L降到52 mg/L。研究成果为实现蒸发母液TOC的高效降解探索出了一条可行的途径,具备显著的实用价值与推广意义。 展开更多
关键词 bdd电极 电化学氧化 盐湖提锂 高TOC蒸发母液 工艺参数
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Analysis of a Double-lined Spectroscopic Binary System Using LAMOST and TESS Data
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作者 Daoye Yang Jianrong Shi +4 位作者 Ali Esamdin Chunqian Li Xiang-Lei Chen Rivkat Karimov Shuhrat A.Ehgamberdiev 《Research in Astronomy and Astrophysics》 2025年第9期123-131,共9页
We present a detailed analysis of a double-lined spectroscopic binary system,Bo Gem,using data obtained from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST)and the Transiting Exoplanet Survey Sat... We present a detailed analysis of a double-lined spectroscopic binary system,Bo Gem,using data obtained from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST)and the Transiting Exoplanet Survey Satellite(TESS).By applying spectral disentangling techniques to the LAMOST Medium Resolution Spectra,we determine the orbital parameters,including the orbital period of P=4.0689 days,and semimajor axis of a=14.90±0.04 R_(⊙).The mass ratio between the two components is found to be q=0.198±0.006,with an inclination of i=82°.3±0°.13.The photometric data from TESS revealed periodic light variations due to the eclipsing nature of the system,allowing for the determination of the primary star’s radius as R_(1)=1.68±0.03 R_(⊙)and the secondary star’s radius as R_(2)=3.68±0.04 R_(⊙).The effective temperatures of the primary and secondary stars are measured to be T_(eff,1)=9705±50 K and T_(eff,2)=5830±22 K,respectively.By analyzing the disentangled spectra,we determined the stellar atmospheric parameters—including surface gravity and metallicity of both stars.These results not only confirm the double-lined spectroscopic binary status of Bo Gem,but also underscore its value as an important system for testing and refining stellar evolution models. 展开更多
关键词 (stars:)binaries eclipsing-(stars:)binaries spectroscopic-(stars:)binaries general
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Transcending Binary Opposition: Exploring the Path to Harmonious Coexistence of Humanity From a Philosophical Perspective
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作者 CUI Weicheng 《Philosophy Study》 2025年第2期49-60,共12页
This paper analyzes binary opposition thinking,dominant in Western societies since ancient Greece,its prevalence in philosophy,international relations,etc.While it influenced science and technology,it also caused conf... This paper analyzes binary opposition thinking,dominant in Western societies since ancient Greece,its prevalence in philosophy,international relations,etc.While it influenced science and technology,it also caused conflicts,hindering the sustainable development of humanity.The paper explores the“binary co-existence”philosophy from Eastern thought.It explains its basis,applications,and significance in overcoming global social issues currently encountered.This philosophy emphasizes mutual dependence of opposites,offering solutions to global challenges.The paper stresses the urgency of shifting from binary opposition to binary co-existence,crucial for resolving conflicts and promoting sustainable development.It discusses ways like education and media to achieve this for global harmony. 展开更多
关键词 binary opposition binary co-existence thinking paradigm global challenges sustainable development TRANSFORMATION
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Revised Orbital,Physical,Stability,and Habitability Parameters of the Binary System HD 25811 Using Gaia Observations
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作者 Hassan B.Haboubi Mashhoor A.Al-Wardat +5 位作者 Ahmad A.Abushattal Maximiliano Dirk Hatem Widyan Naufa Nazar Joshua V.Thomji Suhail Masda 《Research in Astronomy and Astrophysics》 2025年第12期147-156,共10页
Al-Wardat's method is used in this research to analyze the two components of the HD 25811 binary system,which combines the results of speckle interferometry with the astrometric data to construct the synthetic spe... Al-Wardat's method is used in this research to analyze the two components of the HD 25811 binary system,which combines the results of speckle interferometry with the astrometric data to construct the synthetic spectral energy distribution of the system.The method results in the effective temperatures at 7100±50 K for component A and 7000±50 K for component B,while their masses measure as 1.65±0.15M_(⊙)for component A and1.58±0.14M_(⊙)for component B.The system exists at an estimated age of 0.794 Gyr,while both stars remain in their initial subgiant evolutionary phase.The evolutionary tracks together with isochrones for Z=0.03 validate that the system components share both their origin and chemical compositions.The orbital analysis shows that the system has a period of 15.97 yr and an eccentricity of 0.713,while the total system mass amounts to3.65±0.49 M_(⊙).We detailedly analyze the system's orbital dynamics to assess planetary stability and habitability zones,which lead to the dynamics of circumbinary(P-type)and circumstellar(S-type)orbits using empirical criteria,revealing large regions in which planetary orbits remain dynamically stable.Luminosities and effective temperatures of each stellar component are used to determine their habitable zones. 展开更多
关键词 (stars:)binaries(including multiple):close (stars:)binaries:visual (stars:)binaries:spectroscopic stars:evolution Astrometry and Celestial Mechanics
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BDD电化学在电镀废水处理中去除有机物的应用研究
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作者 刘超 王顺 《清洗世界》 2025年第11期4-6,共3页
由于生产制作工艺不同,不同电镀废水的水质情况及其中的杂质类型各有不同,在众多电镀废水中,化学镀镍废水含大量络合物,传统废水处理工艺(如混凝沉淀、微滤膜过滤等)无法去除水中络合镍,电镀废水处理效果自然无法达到排放要求,出水镍含... 由于生产制作工艺不同,不同电镀废水的水质情况及其中的杂质类型各有不同,在众多电镀废水中,化学镀镍废水含大量络合物,传统废水处理工艺(如混凝沉淀、微滤膜过滤等)无法去除水中络合镍,电镀废水处理效果自然无法达到排放要求,出水镍含量超标,必须实施破络预处理。除此以外,化学镍废水中含大量有机污染物,极难降解,易引起膜系统污堵,将严重影响膜产水量,从而膜清洗周期缩短,需使用酸碱清洗。 展开更多
关键词 电镀废水 bdd电化学 有机物
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WC-Co/BDD电极在染料废水降解脱色中的应用
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作者 张韬 李英之 +2 位作者 刘浩伍 邹西壮 薛喆 《金刚石与磨料磨具工程》 北大核心 2025年第6期769-778,共10页
针对4种不同类型的染料废水,利用WC-Co基掺硼金刚石(boron-doped diamond,BDD)电极,研究其降解脱色效果。通过热丝化学气相沉积在WC-Co基体上制备BDD薄膜,并利用场发射扫描电镜和拉曼光谱对其进行表征;利用制备的BDD电极,以活性艳红X-3... 针对4种不同类型的染料废水,利用WC-Co基掺硼金刚石(boron-doped diamond,BDD)电极,研究其降解脱色效果。通过热丝化学气相沉积在WC-Co基体上制备BDD薄膜,并利用场发射扫描电镜和拉曼光谱对其进行表征;利用制备的BDD电极,以活性艳红X-3B、茜素红、亚甲基蓝、孔雀石绿为目标污染物,探究降解参数对脱色效率的影响,并获得较优降解参数;在此基础上,针对不同的染料分别实施3次重复性降解氧化实验,考察化学需氧量(chemical oxygen demand,COD)的矿化效果。结果表明,4种染料模拟废水的最优槽电压均为6~7 V,但匹配的最优电解质浓度和pH值各不相同,主要归因于各染料的分子结构不同。当通电量为4 Ah/L时,活性艳红X-3B、亚甲基蓝、孔雀石绿的COD去除率> 97%,而茜素红的COD去除率约为70%,表现出较高的氧化降解难度。4种染料的电解氧化难易顺序为:活性艳红X-3B<孔雀石绿<亚甲基蓝<茜素红;WC-Co/BDD电极在处理染料废水时的效果与常规基体BDD电极相当。 展开更多
关键词 硼掺杂金刚石电极 硬质合金 染料废水 化学需氧量 电压 电解质
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UV Flux Variation Study in Contact Binary VW Cephei
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作者 Anurag Baruah Mayukh Pahari 《Research in Astronomy and Astrophysics》 2025年第10期262-271,共10页
Despite many attempts,the origin of UV emission line and continuum in contact binary stars remains unclear.We present a substantial UV spectroscopic analysis of VW Cephei,a late-type contact binary system,using 46 low... Despite many attempts,the origin of UV emission line and continuum in contact binary stars remains unclear.We present a substantial UV spectroscopic analysis of VW Cephei,a late-type contact binary system,using 46 lowresolution spectra from the International Ultraviolet Explorer in the wavelength range 1150-1978À.By modeling continuum and emissions lines in individual spectra,we report the significant detection of O Ⅲ](1660 and 1666À)and Si Ⅳ(1393 and 1402À)line complexes.We observe that UV fluxes for both continuum and emission lines like C Ⅳ,O Ⅲ],C Ⅱ and Si Ⅳ vary significantly(fractional rms variability up to 45%)from hours to years.In addition,line widths also change by hundreds of km s^(-1).The UV flux variabilities observed in the continuum bands and line emissions are uncorrelated.However,most of the flux values follow the binary orbital period observed from optical data.Our analysis indicates that,while the variation in continuum flux may be attributed to a heated photosphere,the line width measurements indicate that the emission lines are likely formed in the dynamical clouds associated with Roche lobe overflow.We estimate the mass transfer rate of M=(0.82±0.01)×10^(-7)M_(⊙)yr^(-1)from UV line fluxes,which is in good agreement with optical studies. 展开更多
关键词 techniques spectroscopic-(stars )binaries eclipsing-ultraviolet STARS
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Superior Energy Storage Performance in Crosslinked Binary Polymers at High Temperatures Via Confnement Effect
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作者 Yongbin Liu Yating Xu +6 位作者 Jinghui Gao Jingzhe Xu Ming Wu Zhengwei Liu Yilong Wang Xiaojie Lou Lisheng Zhong 《Energy & Environmental Materials》 2025年第2期201-206,共6页
High-temperature performance of energy storage dielectric polymers is desired for many electronics and electrical applications,but the trade-off between energy density and temperature stability remains fundamentally c... High-temperature performance of energy storage dielectric polymers is desired for many electronics and electrical applications,but the trade-off between energy density and temperature stability remains fundamentally challenging.Here,we report a general material design strategy to enhance energy storage performance at high temperatures by crosslinking a polar polymer and a high glass-transition temperature polymer as a crosslinked binary blend.Such crosslinked binary polymers display a temperature-insensitive and high energy density behavior of about6.2~8.5 J cm^(-3) up to 110℃,showing a significant enhancement in thermal resistant properties and consequently outperforming most of the other ferroelectric polymers.Further microstructural investigations reveal that the improved thermal stability stems from the confinement effect on conformational motion of the crosslinking network,which is evidenced by the increased rigid amorphous fraction and steady intermolecular distance of amorphous regions from temperature-dependent X-ray diffraction results.Our findings provide a general and straightforward strategy to attain temperature-stable,high-energy-density polymer-based dielectrics for energy storage capacitors. 展开更多
关键词 crosslinking binary DIELECTRIC energy storage high temperature polymer
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Analysis of the consistency status and influencing factors of binary symptom assessment in patients with heart failure
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作者 Chen-Ming Li Gu-Yue Yan +2 位作者 Lu Yu Qi Zhang Qing Wu 《Nursing Communications》 2025年第22期1-12,共12页
Background:To investigate the consistency level of binary symptom assessment in patients with heart failure and their primary caregivers,and to analyze the related factors influencing consistency.Methods:By using the ... Background:To investigate the consistency level of binary symptom assessment in patients with heart failure and their primary caregivers,and to analyze the related factors influencing consistency.Methods:By using the convenience sampling method,patients with heart failure and their main caregivers in the Department of Cardiology of a tertiary hospital in Suzhou from May to November 2023 were selected as the research subjects.The HFSS scale was used for data collection.The paired t-test or paired Wilcoxon test was used to evaluate the differences in the binary symptom assessment scores of heart failure.The intraclass correlation coefficient was used to assess the consistency level of the binary symptom assessment.The Pearson correlation test was used to examine the correlation of the binary symptom assessment.Regression analysis was employed to explore the factors related to the consistency assessment.Results:A total of 103 pairs of valid questionnaires were collected.The consistency levels of symptom evaluations in patients with heart failure and their primary caregivers were statistically significant(P<0.05).The most frequently reported and severe symptom by patients with heart failure and their primary caregivers is shortness of breath during activity.Both have a high consensus on the severity and urgency of most heart failure symptoms.The patient’s gender,body mass index,number of children,history of diabetes,number of comorbidities,mean arterial pressure,LVEF,number of stents,whether a defibrillator was implanted,as well as the gender,marital status,education level,relationship with the patient,care time,whether they lived together,and communication and interaction situation of the main caregiver were the influencing factors for the consistency of binary symptom assessment of heart failure(P<0.05).Conclusion:The degree of consistency in binary symptom assessment between patients with heart failure and their primary caregivers was moderate or higher,which emphasizes the importance of including binary groups in clinical assessment. 展开更多
关键词 heart failure symptom assessment binary consistency study
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NR Cam:A New Active Low Mass-ratio Contact Binary with a Potential Third Companion
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作者 Jie Wei Chao-Yue Li +8 位作者 Lin-Qiao Jiang Jie Zheng Kai Huang Yi-Man Liu Shuang Gou Mu-Lan Deng Li-Jun Mei Lin Cao Xiao-Yu Long 《Research in Astronomy and Astrophysics》 2025年第9期213-225,共13页
This study presents a detailed photometric and spectroscopic analysis of the W UMa-type binary NR Cam,using data from the Transiting Exoplanet Survey Satellite(TESS)and ground-based observations.The light curves exhib... This study presents a detailed photometric and spectroscopic analysis of the W UMa-type binary NR Cam,using data from the Transiting Exoplanet Survey Satellite(TESS)and ground-based observations.The light curves exhibit significant variable,with a negative correlation between the brightness of the two maxima—a characteristic of W UMa-type binaries typically attributed to magnetic activity.To explain this behavior,we incorporated a starspot model into our Wilson–Devinney analysis.Our results confirm that NR Cam is a W-subtype,moderately contact binary with a low mass ratio of q=5.75(±0.03)and a fill-out factor of f=33.4(±3.1)%.We also analyzed the orbital period variation using all available times of minima.The resulting O−C diagram reveals a long-term decreasing trend in the orbital period at a rate of dP/dt=−5.18(±0.02)×10^(-8) day yr^(-1),superimposed with a periodic oscillation characterized by an amplitude of A_(3)=0.0019(±0.0001)day and an oscillation period of P_(3)=7.776(±0.003)yr.The long-term decrease is likely due to mass transfer between the binary components,with an estimated mass transfer rate of dM_(2)/dt=1.33(±0.01)×10^(-8)M_(⊙)yr^(-1).The periodic oscillations are likely driven by the light-travel time effect caused by a tertiary companion,with a minimum mass of M_(3)=0.0956(1)M_(⊙)and a maximum separation of 3.841(6)au.Additionally,we considered the possibility that the periodic variation could result from changes in the gravitational quadrupole moment due to magnetic activity cycles,as described by the Applegate mechanism.Our findings confirm that NR Cam is an active binary system,where magnetic activity plays a significant role in its orbital evolution.These results contribute to our understanding of the magnetic dynamics and evolutionary processes in contact binary systems. 展开更多
关键词 (stars:)binaries(including multiple) close-(stars:)binaries eclipsing-(stars:)starspots
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Modelling Microsegregation of Binary Alloy During Solidification
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作者 Tongzhao Gong Shuting Cao +4 位作者 Weiye Hao Weiqi Fan Yun Chen Xing-Qiu Chen Dianzhong Li 《Acta Metallurgica Sinica(English Letters)》 2025年第9期1628-1636,共9页
This work studies the impact of the carbon diffusion on the growth kinetics of austenite and the solute segregation,by utilizing the phase-field(PF)method to simulate the solidification of a Fe-C binary alloy.It is re... This work studies the impact of the carbon diffusion on the growth kinetics of austenite and the solute segregation,by utilizing the phase-field(PF)method to simulate the solidification of a Fe-C binary alloy.It is revealed that increasing the ratio of the carbon diffusion coefficient in solid to that in liquid is advantageous in reducing the solute segregation,and a novel microsegregation model is developed based on the quantitative analysis of the results from PF simulations.The simplified one-dimensional diffusion simulation is employed to analyse the quantitative relationship between the parameters of the proposed microsegregation model and the properties of materials.The universality and reliability of the new microsegregation model are then validated by comparing with the experimental data of various alloy systems.These findings contribute to our comprehension of the fundamental theory of solidification and also provide a potential and promising approach to controlling the solidification microstructure. 展开更多
关键词 binary alloy SOLIDIFICATION MICROSEGREGATION Phase-field method Solid back diffusion
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Exploring structure-property relationships of critical temperatures for binary refrigerant mixtures via group contribution and machine learning
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作者 Jintao Wu Yachao Pan +1 位作者 Jiahui Ren Qibin Li 《DeCarbon》 2025年第3期35-43,共9页
Thermodynamic cycles are the main approach of energy conversion,which is the main source of carbon emis-sion.The working fluid is the energy carrier of thermodynamic cycles.And refrigerant is widely employed in low an... Thermodynamic cycles are the main approach of energy conversion,which is the main source of carbon emis-sion.The working fluid is the energy carrier of thermodynamic cycles.And refrigerant is widely employed in low and medium grade energy utilization and heating ventilation and air conditioning.The refrigerant mixtures can effectively combine the advantages of their components,which plays a key role in decarbonization.As a basic thermophysical property,critical temperature,T_(c),plays an important role in thermodynamic calculation and thermodynamics system design.In this work,the structure-property relationship models of T_(c) for binary re-frigerants were established by developing predictive models based on 61 binary refrigerants with 275 sets of experimental T_(c) data and six machine learning algorithms.Also,specific halogenated groups of refrigerants are used to characterize the components and molecular structures of binary mixtures.The Multiple-layer Perceptron model owns the best fitting and generalization ability with the average deviation is lower than 2%.Compared with conventional methods,the proposed model does not rely on any experimental property data or empirical parameters,and can accurately predict T_(c) of binary refrigerant mixtures directly from their components and mixing ratios.The present work could be guided in building predictive models for other properties,thereby supporting the development of novel refrigerant mixtures. 展开更多
关键词 REFRIGERANTS binary mixtures Thermophysical properties Critical temperature Machine learning
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Space-Borne Interferometers to Detect Thousands of Memory Signals Emitted by Stellar-Mass Binary Black Holes
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作者 Shaoqi Hou Zhi-Chao Zhao +1 位作者 Zhoujian Cao Zong-Hong Zhu 《Chinese Physics Letters》 2025年第10期323-330,共8页
The gravitational memory effect manifests gravitational nonlinearity,degenerate vacua,and asymptotic symmetries;its detection is considered challenging.We propose using a space-borne interferometer to detect memory si... The gravitational memory effect manifests gravitational nonlinearity,degenerate vacua,and asymptotic symmetries;its detection is considered challenging.We propose using a space-borne interferometer to detect memory signals from stellar-mass binary black holes(BBHs),typically targeted by ground-based detectors.We use DECIGO detector as an example.Over 5 years,DECIGO is estimated to detect approximately 2,036 memory signals(SNRs>3)from stellar-mass BBHs.Simulations used frequency-domain memory waveforms for direct SNR estimation.Predictions utilized a GWTC-3 constrained BBH population model(Power law+Peak mass,DEFAULT spin,Madau-Dickinson merger rate).The analysis used conservative lower merger rate limits and considered orbital eccentricity.The high detection rate stems from strong memory signals within DECIGO’s bandwidth and the abundance of stellar-mass BBHs.This substantial and conservative detection count enables statistical use of the memory effect for fundamental physics and astrophysics.DECIGO exemplifies that space interferometers may better detect memory signals from smaller mass binaries than their typical targets.Detectors in lower frequency bands are expected to find strong memory signals from∼10^(4)M⊙binaries. 展开更多
关键词 space borne interferometer detect memory signals gravitational memory effect decigo detector binary black holes bbhs typically stellar mass binary black holes signal noise ratio
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New Orbital Parameters of 850 Wide Visual Binary Stars and Their Statistical Properties
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作者 Igor Izmailov Maxim Khovritchev 《Research in Astronomy and Astrophysics》 2025年第1期321-331,共11页
Based on positional observations and measurements of radial velocities,the orbits of 850 wide visual binary stars have been determined.The parameters of the log-normal distributions for the histograms of orbital perio... Based on positional observations and measurements of radial velocities,the orbits of 850 wide visual binary stars have been determined.The parameters of the log-normal distributions for the histograms of orbital periods,stellar masses,and semimajor axes in astronomical units have been obtained.The eccentricity histogram for binary stars with orbital periods less than 400 yr follows a normal distribution centered at e=0.545+/−0.029.For stars with longer periods,this distribution obeys the law f=2e,with accuracy to errors.The mass-to-luminosity relation for stars with well-determined masses is given by:log L_(⊙)=4.33 logM_(⊙)-0.11,where L_(⊙) and M_(⊙) are the luminosity and mass of the star in units of the solar luminosity and mass,respectively. 展开更多
关键词 (stars:)binaries visual-stars statistics-stars fundamental parameters
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