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REACTIVITY RATIOS FOR COPOLYMERIZATION WITH THE PARTICIPATION OF A CHARGE-TRANSFER COMPLEX
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作者 Guo-rong Shan Zhi-xue Weng +1 位作者 Zhi-ming Huang Zu-ren Pan Institute of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2000年第5期423-430,共8页
The complexation between styrene (St) and N-phenylmaleimide (PMI) was investigated by H-1-NMR spectroscopy, and the existence of a complex was proved. The equilibrium constant of St/PMI in chloroform at 50 degrees C w... The complexation between styrene (St) and N-phenylmaleimide (PMI) was investigated by H-1-NMR spectroscopy, and the existence of a complex was proved. The equilibrium constant of St/PMI in chloroform at 50 degrees C was determined to be 0.27. New elementary propagation reactions were proposed. On the basis of the propagation elementary reactions for copolymerization with the participation of a charge-transfer complex (CTC), a method for measuring the reactivity ratios is presented. Four reactivity ratios and relative reactivities of free monomer and CTC were obtained. They are r(12) = 0.034, r(21) = 0.012, r(1C) = 0.0030, r(2C) = 0.0034, and k(1C)/k(12) = 11.34, k(2C)/k(21) = 3.42. 展开更多
关键词 charge-transfer complex COPOLYMERIZATION reactivity ratio
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Reduced Partition Function Ratio in the Frequency Complex Plane: A Mathematical Approach
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作者 Jie Yuan 《Open Journal of Geology》 2014年第12期654-664,共11页
This paper gives a mathematical approach to calculate the fractionation factor of isotopes in a general cluster (also known as?super-molecule), which composes of necessary chemical effect within three bonds outside th... This paper gives a mathematical approach to calculate the fractionation factor of isotopes in a general cluster (also known as?super-molecule), which composes of necessary chemical effect within three bonds outside the interested atom(s). The cluster might have imaginary frequencies after being optimized in quantum softwares. The approach includes the contribution of the difference, which is resulted from the substitution of heavy and light isotopes in the cluster, of vibrations of imaginary frequencies to give precise prediction of isotope fractionation factor. We call the new mathematical approximation “reduced partition function ratio in the frequency complex plane (RPFRC)”. If there is no imaginary frequency for a cluster, RPFRC?is simplified to be Urey (1947) or Bigeleisen and Mayer (1947) formula. Final results of this new algorithm are in good agreement with those in earlier studies. 展开更多
关键词 ISOTOPE FRACTIONATION Cluster REDUCED PARTITION Function ratio FREQUENCY complex Plane
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The Golden Ratio Theorem: A Framework for Interchangeability and Self-Similarity in Complex Systems
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作者 Alessandro Rizzo 《Advances in Pure Mathematics》 2023年第9期559-596,共38页
The Golden Ratio Theorem, deeply rooted in fractal mathematics, presents a pioneering perspective on deciphering complex systems. It draws a profound connection between the principles of interchangeability, self-simil... The Golden Ratio Theorem, deeply rooted in fractal mathematics, presents a pioneering perspective on deciphering complex systems. It draws a profound connection between the principles of interchangeability, self-similarity, and the mathematical elegance of the Golden Ratio. This research unravels a unique methodological paradigm, emphasizing the omnipresence of the Golden Ratio in shaping system dynamics. The novelty of this study stems from its detailed exposition of self-similarity and interchangeability, transforming them from mere abstract notions into actionable, concrete insights. By highlighting the fractal nature of the Golden Ratio, the implications of these revelations become far-reaching, heralding new avenues for both theoretical advancements and pragmatic applications across a spectrum of scientific disciplines. 展开更多
关键词 Conservation Law SELF-SIMILARITY INTERCHANGEABILITY Golden ratio complex Systems Dynamic Exchange Structural Stability Mathematical Modeling Theoretical Framework P vs NP Millennium Problem
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孔隙型碳酸盐岩复合暂堵体积酸压技术探索
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作者 卢澍韬 高纯良 +4 位作者 罗洋 杨婷婷 顾明勇 张永 郭然 《中外能源》 2026年第1期61-65,共5页
针对孔隙型碳酸盐岩储层致密、缝洞弱且连通性差,常规酸压难以经济有效动用的问题,以合川地区茅口组弱云化储层为研究对象,从天然裂缝发育、地应力、岩石力学特征等方面分析体积酸压的可行性。储层天然裂缝较发育、脆性指数在0.43~0.6,... 针对孔隙型碳酸盐岩储层致密、缝洞弱且连通性差,常规酸压难以经济有效动用的问题,以合川地区茅口组弱云化储层为研究对象,从天然裂缝发育、地应力、岩石力学特征等方面分析体积酸压的可行性。储层天然裂缝较发育、脆性指数在0.43~0.6,为形成复杂裂缝提供了有利条件,但中等应力差限制了裂缝复杂程度。为此提出“深穿透、增复杂、强导流”的体积酸压思路,探索采用复合暂堵工艺并优化暂堵剂用量,通过真三轴物模实验、暂堵剂性能评价证明了可有效实现体积改造。优化形成了大规模、中高酸液比例、多级交替注入+复合暂堵改造工艺。在T33井采用酸性压裂液与胶凝酸4级交替注入+复合暂堵工艺,入地总液量1603m^(3),使用暂堵纤维100kg+暂堵颗粒125kg,酸压后试气产量达48.9×10^(4)m^(3)/d,较常规酸压提升220%以上,为同类储层酸压施工提供了借鉴。 展开更多
关键词 孔隙型碳酸盐岩 体积酸压 多级交替注入 复合暂堵 酸液比例 复杂裂缝
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反射波波形反演技术在西部山前带探区中的应用
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作者 王海 徐夷鹏 +3 位作者 赵爱国 王胜阁 刘鹏翔 王蓬 《物探与化探》 2026年第1期128-136,共9页
西部山前带探区作为油气勘探的重要战略接替区,其“双复杂”地表条件(复杂地形与复杂构造)及低信噪比地震资料严重制约了地震成像精度与钻井成功率,亟须针对性的反演技术突破。本文以西部山前带工区为研究对象,该工区地表类型复杂,涵盖... 西部山前带探区作为油气勘探的重要战略接替区,其“双复杂”地表条件(复杂地形与复杂构造)及低信噪比地震资料严重制约了地震成像精度与钻井成功率,亟须针对性的反演技术突破。本文以西部山前带工区为研究对象,该工区地表类型复杂,涵盖山丘、砾石区及雅丹地貌,进一步加剧了地震资料的低品质特征。现有初至波波形反演依赖初至波旅行时拟合,受西部山前带近地表非均质性影响,存在子波一致性差、地表一致性差的两大核心局限,浅层速度建模精度不足,难以依赖超大偏移距数据以及初至波中丰富的低频信息对中深层速度进行反演;反射波波形反演通过挖掘反射波中深层信息,优化目标函数,对低品质资料具有更强的适应性。基于此,本文将反射波波形反演应用于工区,旨在提升双复杂条件下的偏移速度反演精度,为改善西部山前带探区地震成像质量、支撑油气藏精细描述提供技术参考。通过模型和工区测试,反射波波形反演的结果能够应对山前带的低品质数据,提升中深层速度的整体精度。 展开更多
关键词 双复杂地表 低信噪比地震资料 低频反演 反射波波形反演
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Inclusion Complex of Paclitaxel in Hydroxypropyl-β-cyclodextrin 被引量:1
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作者 CHEN Yue ZHOU Yu-lai +1 位作者 REN Yong YAN Wei-qun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第6期749-752,共4页
Introduction Paclitaxel (as Taxol) is a kind of diterpenoid natural product extracted from Chinese yew. It has been reported to have high anti-tumor effects, such as the activity against oophorama, mammary cancer, ... Introduction Paclitaxel (as Taxol) is a kind of diterpenoid natural product extracted from Chinese yew. It has been reported to have high anti-tumor effects, such as the activity against oophorama, mammary cancer, encephaloma, cervical carcinoma, and non- small-cell lung carcinoma. One of the major problems of paclitaxel applied to therapy is its extremely low solubility in water. In addition, paclitaxel is administered as a slow infusion in a vehicle consisting of Cremophor EL ( polyoxyethylated castor oil ). However, Cremophor has been observed to cause severe, occasionally fatal hypersensitivity reactions in animals and humans. Therefore, paclitaxel therapy includes a prophylactic regimen of antihistamines and corticosteroids , along with a prolonged infusion time to reduce the severity and incidence of hypersensitivity reactions. Because of the reasons mentioned above, currently its preparation needs to be improved further. 展开更多
关键词 PACLITAXEL HP-β-CD Inclusion complex Combinative ratio
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复杂悬挑+转换+跃层体系云塔楼结构设计难点分析
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作者 夏昊 孙超 李寅斌 《建筑结构》 北大核心 2026年第4期93-100,共8页
重庆某邮轮港综合体项目由6个云塔楼、5个连桥以及大底盘裙房构成,通过设置两道防震缝分解为三个独立抗震单元,每个单元均由“大底盘双塔+弱连接连桥”构成。其中云塔楼为钢框架-混凝土剪力墙结构,连桥由4个钢桁架和1个悬索桥构成。以3#... 重庆某邮轮港综合体项目由6个云塔楼、5个连桥以及大底盘裙房构成,通过设置两道防震缝分解为三个独立抗震单元,每个单元均由“大底盘双塔+弱连接连桥”构成。其中云塔楼为钢框架-混凝土剪力墙结构,连桥由4个钢桁架和1个悬索桥构成。以3#~4#云大底盘双塔及3#云塔楼为重点,阐述悬挑+转换+跃层云塔楼结构楼面桁架的布置难点,以及设计过程中如何解决多塔周期比、层间刚度比、承载力比、巨柱设计、楼盖设计、节点设计等难题。结果表明:与核心筒角部相连的转换桁架应优先采用正交布置,以保证施工可靠性;长悬挑多塔模型的周期比相较于单塔模型更为敏感,弱化周边区域荷载是解决问题的关键;跃层结构的层间刚度比及层间承载力比需注重并层数据处理,避免薄弱层误判;圆钢管柱的防连续倒塌设计可采用偶然荷载法结合直接分析法验算;悬挑转换结构楼盖设计应考虑施工次序的优化,设置后浇块,降低楼盖拉应力。 展开更多
关键词 复杂塔楼结构 多塔周期比 防连续倒塌设计 偶然荷载法 空间板壳受力 大悬挑桁架节点
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Lithological Discrimination of the Mafic-Ultramafic Complex, Huitongshan, Beishan, China: Using ASTER Data 被引量:11
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作者 Lei Liu Jun Zhou +2 位作者 Dong Jiang Dafang Zhuang Lamin R Mansaray 《Journal of Earth Science》 SCIE CAS CSCD 2014年第3期529-536,共8页
The Beishan area has more than seventy mafic-ultramafic complexes sparsely distributed in the area and is of a big potential in mineral resources related to mafic-ultramafic intrusions. Many mafic-ultramafic intrusion... The Beishan area has more than seventy mafic-ultramafic complexes sparsely distributed in the area and is of a big potential in mineral resources related to mafic-ultramafic intrusions. Many mafic-ultramafic intrusions which are mostly in small sizes have been omitted by previous works. This research takes Huitongshan as the study area, which is a major district for mafic-ultramafic occurrences in Beishan. Advanced spaceborne thermal emission and reflection radiometer(ASTER) data have been processed and interpreted for mapping the mafic-ultramafic complex. ASTER data were processed by different techniques that were selected based on image reflectance and laboratory emissivity spectra. The visible near-infrared(VNIR) and short wave infrared(SWIR) data were transformed using band ratios and minimum noise fraction(MNF), while the thermal infrared(TIR) data were processed using mafic index(MI) and principal components analysis(PCA). ASTER band ratios(6/8, 5/4, 2/1) in RGB image and MNF(1, 2, 4) in RGB image were powerful in distinguishing the subtle differences between the various rock units. PCA applied to all five bands of ASTER TIR imagery highlighted marked differences among the mafic rock units and was more effective than the MI in differentiating mafic-ultramafic rocks. Our results were consistent with information derived from local geological maps. Based on the remote sensing results and field inspection, eleven gabbroic intrusions and a pyroxenite occurrence were recognized for the first time. A new geologic map of the Huitongshan area was created by integrating the results of remote sensing, previous geological maps and field inspection. It is concluded that the workflow of ASTER image processing, interpretation and ground inspection has great potential for mafic-ultramafic rocks identifying and relevant mineral targeting in the sparsely vegetated arid region of northwestern China. 展开更多
关键词 mafic-ultramafic complex ASTER data band ratio minimum noise fraction mafic index principal component analysis.
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“Place Making”in Urban Complex Design: A Case Study of Tianfu Pearl Design Scheme
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作者 ZHAO Xiangwei LI Yanning 《Journal of Landscape Research》 2016年第5期23-26,32,共5页
This paper introduced basic situation and challenges of Block 9, Dongdajie, Chengdu City, expounded basic definition and design concept of "place making", briefed the design scheme from three aspects, namely... This paper introduced basic situation and challenges of Block 9, Dongdajie, Chengdu City, expounded basic definition and design concept of "place making", briefed the design scheme from three aspects, namely planning layout, space environment and architectural style, and concluded the application of the idea of "place making" in Block 9 design scheme in view of the multi-functional urban complex with high plot ratio. 展开更多
关键词 Urban complex with high plot ratio Place making Commercial canyon
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Application of Complex Daubechies Wavelet in UHF Partial Discharge Measurements 被引量:3
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作者 XIE Yan-bin TANG Ju ZHANG Xiao-xing 《高电压技术》 EI CAS CSCD 北大核心 2008年第12期2701-2707,共7页
On-line partial discharge(PD)detection still remains a very challenging task because of the strong electromagnetic interferences.In this paper,a new method of de-noising,using complex Daubechies wavelet(CDW)transform,... On-line partial discharge(PD)detection still remains a very challenging task because of the strong electromagnetic interferences.In this paper,a new method of de-noising,using complex Daubechies wavelet(CDW)transform,has been proposed.It is a relatively recent enhancement to the real-valued wavelet transform because of tow important properties,which are nearly shift-invariant and availability of phase information.Those properties give CDW transform superiority over other real-valued wavelet transform,and then the construction algorithm of CDW is introduced in detail.Secondly,based on the real threshold algorithm of real-valued wavelet transform,complex threshold algorithm is devised.This algorithm take the different characteristics of real part and imaginary part of complex wavelet coefficients into account,it modifies the real and imaginary parts of complex wavelet coefficients respectively.Thirdly,to obtain a real de-noised signal,new combined information series is devised.By applying different combination of real part and imaginary part of de-noised complex signal,a real de-noised signal can be restored with higher peak signal-to-noise ratio(PSNR)and less distortion of original signals.Finally,On-site applications of extracting PD signals from noisy background by the optimal de-noising scheme based on CDW are illustrated.The on-site experimental results show that the optimal de-noising scheme is an effective way to suppress white noise in PD measurement. 展开更多
关键词 Db复小波 超高频 局部放电 测量 CDW
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Composting MSW and sewage sludge with effective complex microorganisms 被引量:18
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作者 XiBD LiuHL 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第2期264-268,共5页
The effects of complex microorganisms in composting process of the municipal solid waste (MSW) and sludge were examined through inspecting biomass, temperature, oxygen consumption, organic mater, and C/N (the ratio of... The effects of complex microorganisms in composting process of the municipal solid waste (MSW) and sludge were examined through inspecting biomass, temperature, oxygen consumption, organic mater, and C/N (the ratio of carbon and nitrogen). The experimental results shows: complex microorganisms are effective to compose organic matter and speedup composting change into humus. 展开更多
关键词 effective complex microorganisms(ECM) temperature oxygen consumption organic matter C/N ratio
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Phosphate Desorption Characteristics of Some Representative Soils of Bangladesh: Effect of Exchangeable Anions, Water Molecules and Solution to Soil Ratios
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作者 Mohammad Z. Afsar Sirajul Hoque K. T. Osman 《Open Journal of Soil Science》 2012年第3期234-241,共8页
Establishment of phosphate (P) retention and release capacity of soils is essential for effective nutrient management and environmental protection. In this experiment, we studied the influence of soil properties on P ... Establishment of phosphate (P) retention and release capacity of soils is essential for effective nutrient management and environmental protection. In this experiment, we studied the influence of soil properties on P desorption and the relationship between phosphate sorption and desorption. Among the soil series, the Ghior soil had the highest percent clay (59.32%) and free iron oxide (15241 mg·kg–1) content. Along the catena of the calcareous soils, percent clay contents increased. For sorption study, the soils were equilibrated with 0.01 M CaCl2 solution containing 0, 1, 2, 4, 8, 16, 25, 50, 100 and 150 mg·P·L–1 solution. For desorption, three extractants namely, SO42- (0.005 M) as Na2SO4, HCO3- (0.01 M) as NaHCO3 and distilled water were used at extractant to soil ratios of 30:1, 60:1 and 100:1 (v/w). Among the sorption equations, the Langmuir equation showed better fit to the sorption data at higher P concentrations. The amount of phosphate desorbed by all the three extractants increased significantly with the increasing extractant to soil ratios. Phosphate desorption by and water molecules was highly correlated with pH, percent clay and free iron oxide content of the soil. Significant positive correlation (r > 0.64, P L). Phosphate desorption by SO42- and water molecules was also positively correlated with Freundlich constant, N (r > 0.67, P 0 (r > 0.72, P –0.77, P L). The results suggest that freshly sorbed phosphate ions (inner-sphere complex forming species) can be readily desobed by outer-sphere complex forming species like sulphate and bicarbonate ions. Water molecules also desorbed significant amount of freshly sorbed phosphate from the soil colloids. 展开更多
关键词 PHOSPHATE Sorption EXTRACTANT to SOIL ratio Surface complexATION of ANIONS Labile Forms of P PHOSPHATE Desorption
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POLYMER NETWORK-POLY(ETHYLENE GLYCOL)COMPLEXES WITH SHAPE MEMORY EFFECT
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作者 Yi-ping Cao +1 位作者 C.W.Yip 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第1期29-33,共5页
The complexes of poly(methacrylic acid-co-methyl methacrylate) network with poly(ethylene glycol) stabilized byhydrogen bonds were prepared. By introducing the poly(ethylene glycol), a large difference in storage modu... The complexes of poly(methacrylic acid-co-methyl methacrylate) network with poly(ethylene glycol) stabilized byhydrogen bonds were prepared. By introducing the poly(ethylene glycol), a large difference in storage modulus below andabove the glass transition temperature occurred and the complexes exhibited shape memory behaviors. The morphology ofcomplexes was studied by using DSC, WAXD, and DMA. The results indicate that the fixed phase of this kind of novelshape memory materials is the network, and the reversible phase is the amorphous state of PEG:PMAA complex phase. Theshape recoverability almost reaches 100%. This type of complexes can be regarded as a novel shape memory network. 展开更多
关键词 Hydrogen bonded complex Shape memory effect Storage modulus ratio
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Complex of Copper(Ⅱ) with 1, 4, 9, 12-Tetraaza Cyclo-2, 3, 6, 7, 10, 14, 15-Tetrabenzocetanan-5, 8, 13, 16-Tetraone by Spectrophotometry
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作者 Zunli Mo 《Rare Metals》 SCIE EI CAS CSCD 2001年第1期24-27,共4页
The spectrophotometric characteristic of a new reagent 1, 4, 9, 12-tetraaza Cyclo-2, 3, 6, 7, 10, 11, 14, 15 tetrabenzocetanan-5, 8, 13, 16-tetraone (TCTCT) and its complex with Cu(Ⅱ) were studied. The reagent and i... The spectrophotometric characteristic of a new reagent 1, 4, 9, 12-tetraaza Cyclo-2, 3, 6, 7, 10, 11, 14, 15 tetrabenzocetanan-5, 8, 13, 16-tetraone (TCTCT) and its complex with Cu(Ⅱ) were studied. The reagent and its complex with Cu(Ⅱ) have a similar maximum absorbance at 446 um. In C6H4(C2O4HK)-NaOH buffer (pH=4.00), the complex of Cu(Ⅱ)-TCTCT formed when it was heated. The absorbance increased with the increase of the concentration of Cu(Ⅱ) in the range of 1 .6x10-7-5.5x 10-5 mol/L. The composition ratio of the complex was formed to be 1: 1 using the molar ratio method. The method was simple, rapid and sensitive, giving an apparent molar absorptivity of 1.25x105 L mol-1 cm-1 and the apparent stability constant of 1 .04x106. The method was directly applied of copper in fresh milk. 展开更多
关键词 complex of Cu (Ⅱ) reagent TCTCT molar ratio method
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复杂孔隙介质两相驱替模式及驱替效率研究
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作者 刘先珊 孙梦 +5 位作者 郑志伟 熊振瑀 于明智 曹伊婷 宋昱霖 黄子宣 《岩土力学》 北大核心 2025年第8期2363-2375,共13页
非常规油气开采、地热开采过程中,复杂孔隙岩石的两相驱替流动特性直接影响其采收率,因此其过程研究备受关注。以4类有序、无序孔隙结构介质为研究对象,自主搭建了微流体试验可视化装置,开展5种流量及4种被驱替流体黏度在介质中的流动... 非常规油气开采、地热开采过程中,复杂孔隙岩石的两相驱替流动特性直接影响其采收率,因此其过程研究备受关注。以4类有序、无序孔隙结构介质为研究对象,自主搭建了微流体试验可视化装置,开展5种流量及4种被驱替流体黏度在介质中的流动特性试验研究,深入分析毛细管数、黏度比及孔隙结构无序性对两相驱替过程的影响规律。结果表明:入侵相分形维数与驱替模式有关,与驱替效率呈正相关,且分形维数是入侵相含量的普适函数。驱替结束时的分布特征与驱替模式密切相关:稳定驱替向毛细指进转变,伴随着被捕获相数量和标准差的增大。毛细指进向黏性指进转变与毛细指进向规则指进的转变相同,伴随着被捕获相数量的减小和标准差的增大。考虑流体黏度比的影响,建立了修正毛细管数与入侵相驱替饱和度的关系式,可预测考虑黏度比影响的驱替效率。 展开更多
关键词 复杂孔隙 结构无序性 毛细管数 黏度比 驱替效率
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基于网络拓扑结构的水网韧性评价模型构建及应用
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作者 张小丽 姜力荣 +4 位作者 马睿 王文川 李彦彬 王慧杰 江晨辉 《干旱区资源与环境》 北大核心 2025年第12期132-144,共13页
水网韧性研究对提升水网运行可靠性与整体抗风险能力至关重要,但目前缺乏标准化评价模型。文中构建了基于网络拓扑结构的水网韧性评价模型:1)基于复杂网络理论构建水网拓扑结构图,将水库、湖泊等抽象为结点,河道、渠道等抽象为边,形成... 水网韧性研究对提升水网运行可靠性与整体抗风险能力至关重要,但目前缺乏标准化评价模型。文中构建了基于网络拓扑结构的水网韧性评价模型:1)基于复杂网络理论构建水网拓扑结构图,将水库、湖泊等抽象为结点,河道、渠道等抽象为边,形成无向网络。2)引入信息熵改进传统结点重要性评价指标(度中心、接近中心、介数中心、特征向量中心),结合加权秩和比(WRSR)方法综合多指标评估结点重要性,通过CRITIC法确定指标权重。3)以网络效率和最大连通子图为指标,结合权重构建韧性评价公式。将模型应用于冀中南地区的现状水网与规划水网,结果表明:改进后的多指标评价方法较单一指标更能准确识别关键结点;规划水网较现状水网韧性提升20.5%,验证了水网结构复杂度与韧性的正相关性;权重分析显示,最大连通子图权重β越大,水网韧性提升越显著,当β为0.9时的韧性表现最佳。该模型为水网韧性量化评估与优化设计提供了科学方法。 展开更多
关键词 水网系统 韧性评价 复杂网络理论 加权秩和比 冀中南水网
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塔里木盆地沙漠区域超深层复杂油气藏地震勘探关键技术进展 被引量:1
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作者 雷刚林 党青宁 +6 位作者 段文胜 邓健峰 徐仲博 郑多明 刘正文 马安 郑炎鑫 《天然气工业》 北大核心 2025年第7期40-49,共10页
塔里木盆地沙漠区域超深层油气资源丰富,是超深层油气勘探开发的重要盆地,但由于表层沙丘类型复杂多样,地下地质特征复杂,导致地震资料信噪比低,成像精度不高。为此,以塔里木盆地沙漠区域超深层复杂油气藏为研究对象,围绕地震勘探中的... 塔里木盆地沙漠区域超深层油气资源丰富,是超深层油气勘探开发的重要盆地,但由于表层沙丘类型复杂多样,地下地质特征复杂,导致地震资料信噪比低,成像精度不高。为此,以塔里木盆地沙漠区域超深层复杂油气藏为研究对象,围绕地震勘探中的采集、处理、解释技术开展研究,形成了一套适用于该地区的油气地震探测技术体系。研究结果表明:①针对沙漠区域地表低降速带厚度大且横向厚度差异明显,地震面波发育以及震源能量下传有限等问题,形成了宽频高能地震激发技术、高灵敏度方阵小组合降噪保真接收等采集技术;②针对沙漠地区超深层地震波信号能量弱、频率低、子波形状严重畸变以及多次波发育等问题,形成了基于压缩感知的超深层弱信号增强技术、三维复数域小波变换压制层间多次波技术,以及包括全深度全层系高精度Q值调查、Q建场及Q偏移,VSP井驱动谐波拓频等技术;③针对沙漠区域超深层构造复杂、圈闭落实程度低的问题,形成了分级断裂刻画与组合技术、叠前相控反演等技术,提高了沙漠区域超深复杂圈闭高精度描述解释技术。结论认为,形成的针对沙漠区域超深层油气地震勘探技术系列,保障了我国油气深地工程的顺利推进,指导了塔里木盆地超深层复杂油气藏的规模增储与高效开发。 展开更多
关键词 塔里木盆地 深地工程 沙漠区域 超深层 复杂油气藏 地震勘探 增能降噪 保真拓频
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圈复杂度比:逆向工程大语言模型评估的新方法
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作者 周越 印杰 +1 位作者 王震 俞睿 《信息化研究》 2025年第4期107-113,137,共8页
当前大语言模型在二进制逆向工程领域的应用面临两大挑战:缺乏统一的量化评估指标,以及现有训练数据集与真实场景存在差距。针对这些问题,本研究提出了基于圈复杂度比的新型评估指标,并系统地探索了大语言模型在逆向工程任务中的优化方... 当前大语言模型在二进制逆向工程领域的应用面临两大挑战:缺乏统一的量化评估指标,以及现有训练数据集与真实场景存在差距。针对这些问题,本研究提出了基于圈复杂度比的新型评估指标,并系统地探索了大语言模型在逆向工程任务中的优化方法。研究构建了包含782个编译单元的来源于CTF竞赛真实题目和人工编译项目的数据集,覆盖了GCC编译器O0—O3四个优化级别。实验结果表明,采用新数据集微调的大语言模型LLM4Decompile(Large Language Model for Decompilation)在圈复杂度比指标上表现突出。该指标通过计算生成代码与源代码的圈复杂度比值,量化逆向工程结果的结构相似性。微调后的模型圈复杂度比平均下降39.4%,其中O0级别下降36%(0.81→0.52), O1级别下降51.25%(0.80→0.39),O2级别下降28.8%(0.80→0.57),O3级别下降38%(0.79→0.49)。本研究证实了圈复杂度比作为逆向工程评估指标的有效性,验证了大语言模型在低层次代码理解任务中的潜力。 展开更多
关键词 二进制逆向工程 大语言模型 圈复杂度比 数据集构建 模型微调 监督式学习
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极化单脉冲导引头角反质心干扰检测方法
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作者 岳旭龙 王罗胜斌 徐振海 《系统工程与电子技术》 北大核心 2025年第8期2486-2497,共12页
单脉冲雷达导引头受到角反质心干扰时,测角结果会产生偏差,从而偏离舰船目标。对抗质心干扰的前提是干扰存在性检测。本文针对极化阵列体制,详细分析单目标和多目标的极化复单脉冲比的统计特性,进而根据恒虚警检测原理推导超椭球判决域... 单脉冲雷达导引头受到角反质心干扰时,测角结果会产生偏差,从而偏离舰船目标。对抗质心干扰的前提是干扰存在性检测。本文针对极化阵列体制,详细分析单目标和多目标的极化复单脉冲比的统计特性,进而根据恒虚警检测原理推导超椭球判决域的闭式解,提出利用极化复单脉冲比的多目标判决算法。在此基础上,根据舰船的距离向扩展特性,提出角反质心干扰存在性检测方法。仿真结果表明,所提算法的检测性能优于常规单脉冲雷达;目标极化散射矩阵会影响所提算法的检测性能;在设定的两种场景下,所提算法均能有效检测。 展开更多
关键词 角反质心干扰 极化复单脉冲比 超椭球判决域 干扰存在性检测
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基于加权圈比的复杂网络关键节点识别方法
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作者 谢涵臣 吴明功 +1 位作者 温祥西 张洺瑜 《物理学报》 北大核心 2025年第14期401-413,共13页
圈比作为一种基于圈结构的量化指标,已在无权无向网络中展现出其在识别关键节点方面的显著优势.传统的圈比未能充分考虑边权信息对网络结构的影响,限制了其在更广泛网络分析中的应用.为了解决这一问题,本文提出了一种加权网络中新的网... 圈比作为一种基于圈结构的量化指标,已在无权无向网络中展现出其在识别关键节点方面的显著优势.传统的圈比未能充分考虑边权信息对网络结构的影响,限制了其在更广泛网络分析中的应用.为了解决这一问题,本文提出了一种加权网络中新的网络分析指标——加权圈比,旨在提升识别加权网络中关键节点的准确性.通过对示例网络的分析,验证了加权圈比的可行性;进一步的实验在多个真实世界的网络中表明,加权圈比不仅与现有的基准指标存在显著差异,而且在评估网络连通性及早期传播覆盖范围方面,总体表现优于包括传统圈比在内的其他基准指标.这些发现强调了加权圈比在网络分析中的潜在价值,尤其是在处理加权网络时的有效性. 展开更多
关键词 复杂网络 圈比 加权圈比 关键节点
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