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Lychrel Numbers in Base 10: A Probabilistic Approach
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作者 Rostand S. Kuitché 《Advances in Pure Mathematics》 2024年第8期667-694,共28页
For decades, Lychrel numbers have been studied on many bases. Their existence has been proven in base 2, 11 or 17. This paper presents a probabilistic proof of the existence of Lychrel number in base 10 and provides s... For decades, Lychrel numbers have been studied on many bases. Their existence has been proven in base 2, 11 or 17. This paper presents a probabilistic proof of the existence of Lychrel number in base 10 and provides some properties which enable a mathematical extraction of new Lychrel numbers from existing ones. This probabilistic approach has the advantage of being extendable to other bases. The results show that palindromes can also be Lychrel numbers. 展开更多
关键词 Probabilistic Approach PALINDROMES Lychrel numbers Iteration function DIGITS
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Physical Properties of the Function and Number of Empirical Macrohardness of the Material: Universal Physical Unit of Measurement of Macro Hardness (Part 2)
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作者 Shtyrov Nikolay 《Journal of Mechanics Engineering and Automation》 2023年第3期79-91,共13页
Results of analytical studies of the physical properties of the function and number of empirical macrohardness based on the standard experimental force diagram of kinetic macroindentation by a sphere.An analytical com... Results of analytical studies of the physical properties of the function and number of empirical macrohardness based on the standard experimental force diagram of kinetic macroindentation by a sphere.An analytical comparison method and a criterion for the similarity of the physical and empirical macrohardness of a material are proposed.The physical properties of the hardness measurement process using the Calvert-Johnson method are shown.The physical reasons for the size effect when measuring macrohardness are considered.The universal physical unit and standard of macrohardness of kinetic macroindentation by a sphere is substantiated. 展开更多
关键词 Physical theory of kinetic indentation method for determining the function and number of physical macrohardness ratio of empirical and physical macrohardness of a material universal physical unit of macrohardness.
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A Number Theoretic Function and Its Mean Value Computation 被引量:1
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作者 李海龙 杨倩丽 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期53-56,共4页
Let p be a prime, n be any positiv e integer, α(n,p) denotes the power of p in the factorization of n! . In this paper, we give an exact computing formula of the mean value ∑ n<Nα(n,p).
关键词 number theoretic function mean value computing formula
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Fuzzy Semi-continuity of fuzzy number-valued function 被引量:3
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作者 Magassy OUS MANE 吴从炘 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第2期139-141,共3页
In this paper we discuss the conecept and property of fuzzy semi continuous function.
关键词 FUZZY numberS FUZZY number-valued function FUZZY SEMI-CONTINUOUS function
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Quantum phase distribution and the number-phase Wigner function of the generalized squeezed vacuum states associated with solvable quantum systems
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作者 G.R.Honarasa M.K.Tavassoly M.Hatami 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第5期265-273,共9页
The quantum phase properties of the generalized squeezed vacuum states associated with solvable quantum systems are studied by using the Pegg-Barnett formalism.Then,two nonclassical features,i.e.,squeezing in the numb... The quantum phase properties of the generalized squeezed vacuum states associated with solvable quantum systems are studied by using the Pegg-Barnett formalism.Then,two nonclassical features,i.e.,squeezing in the number and phase operators,as well as the number-phase Wigner function of the generalized squeezed states are investigated.Due to some actual physical situations,the present approach is applied to two classes of generalized squeezed states:solvable quantum systems with discrete spectra and nonlinear squeezed states with particular nonlinear functions.Finally,the time evolution of the nonclassical properties of the considered systems has been numerically investigated. 展开更多
关键词 squeezed vacuum states solvable quantum systems phase distribution number phaseWigner function
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Ideal Statistically Pre-Cauchy Triple Sequences of Fuzzy Number and Orlicz Functions 被引量:1
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作者 Xue Feng 《Applied Mathematics》 2021年第9期767-774,共8页
In this paper, we extend the notions of ideal statistically convergence for sequence of fuzzy number. We introduce the notions ideal statistically pre-Cauchy triple sequences of fuzzy number about Orlicz function, and... In this paper, we extend the notions of ideal statistically convergence for sequence of fuzzy number. We introduce the notions ideal statistically pre-Cauchy triple sequences of fuzzy number about Orlicz function, and give some correlation theorem. It is shown that <em>x</em> = {<em>x<sub>ijk</sub></em>} is ideal statistically pre-Cauchy if and only if <img src="Edit_0f9eaa1e-440b-4bac-8bae-c50bb5e5c244.bmp" alt="" /> <em>D </em>(<em>x<sub>ijk</sub></em>, <em>x<sub>pqr</sub></em>) ≥ <em>ε</em>, <em>i</em> ≤ <em>m</em>,<em> j </em>≤ <em>n</em>, <em>t </em>≤ <em>k</em>}| ≥ <em>δ</em>} &#8712;<em>I</em>. At the same time, we have proved <em>x</em> = {<em>x<sub>ijk</sub></em>} is ideal statistically convergent to <em>x</em><sub>0</sub> if and only if <img src="Edit_343f4dfc-82c3-4985-aebc-95c52795bb2f.bmp" alt="" />. Also, some properties of these new sequence spaces are investigated. 展开更多
关键词 Fuzzy numbers Ideal Statistical Convergence Orlicz functions
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On AP-Henstock Integrals of Interval-Valued Functions and Fuzzy-Number-Valued Functions
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作者 Muawya Elsheikh Hamid Alshaikh Hamed Elmuiz Mohammed Eldirdiri Sheima 《Applied Mathematics》 2016年第18期2285-2295,共11页
In 2000, Wu and Gong [1] introduced the thought of the Henstock integrals of inter-valvalued functions and fuzzy-number-valued functions and obtained a number of their properties. The aim of this paper is to introduce... In 2000, Wu and Gong [1] introduced the thought of the Henstock integrals of inter-valvalued functions and fuzzy-number-valued functions and obtained a number of their properties. The aim of this paper is to introduce the thought of the AP- Henstock integrals of interval-valued functions and fuzzy-number-valued functions which are extensions of [1] and investigate a number of their properties. 展开更多
关键词 Fuzzy numbers AP-Henstock Integrals of Interval-Valued functions AP-Henstock Integrals of Fuzzy-number-Valued functions
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On Henstock-Stieltjes Integrals of Interval-Valued Functions and Fuzzy-Number-Valued Functions
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作者 Muawya Elsheikh Hamid Alshaikh Hamed Elmuiz 《Journal of Applied Mathematics and Physics》 2016年第4期779-786,共8页
In this paper we introduce the notion of the Henstock-Stieltjes (HS) integrals of interval-valued functions and fuzzy-number-valued functions and discuss some of their properties.
关键词 Fuzzy numbers Henstock-Stieltjes (HS) Integrals of Interval-Valued functions Henstock-Stieltjes (HS) Integrals of Fuzzy-number-Valued functions
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IS THE“DEGREE OF AGGREGATION”A FUNCTION OF THE AVERAGE AGGREGATE NUMBER,OR OF THE NUMBER OF AGGREGATES,OR BOTH?
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作者 Xi Kui JIANG Jin Tao ZHANG Shanghai Institute of Organic Chemistry,Academia Sinica,345 Ling-ling LU,Shanghai 200032 Zhen He TONG Laboratory of Photochemistry,Institute of Photographic Chemistry,Academia Sinica,Beijing 100101 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第9期675-676,共2页
Measurement of the average aggregate number of coaggregates(N_co)and evaluation Of the number of coaggregates([CoAg])in the region of increasing degree of aggregation shows that only N_co increases linearly with the c... Measurement of the average aggregate number of coaggregates(N_co)and evaluation Of the number of coaggregates([CoAg])in the region of increasing degree of aggregation shows that only N_co increases linearly with the concentration of the target molecules CE-In and BL-ol. 展开更多
关键词 Menger A function OF THE AVERAGE AGGREGATE number OR OF THE number OF AGGREGATES OR BOTH DEGREE OF AGGREGATION IS THE Figure OC
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Describing Fuzzy Membership Function and Detecting the Outlier by Using Five Number Summary of Data
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作者 Md. Farooq Hasan Md. Abdus Sobhan 《American Journal of Computational Mathematics》 2020年第3期410-424,共15页
One of the most important activities in data science is defining a membership function in fuzzy system. Although there are few ways to describe membership function like artificial neural networks, genetic algorithms e... One of the most important activities in data science is defining a membership function in fuzzy system. Although there are few ways to describe membership function like artificial neural networks, genetic algorithms etc.;they are very complex and time consuming. On the other hand, the presence of outlier in a data set produces deceptive results in the modeling. So it is important to detect and eliminate them to prevent their negative effect on the modeling. This paper describes a new and simple way of constructing fuzzy membership function by using five-number summary of a data set. Five states membership function can be created in this new method. At the same time, if there is any outlier in the data set, it can be detected with the help of this method. Usually box plot is used to identify the outliers of a data set. So along with the new approach, the box plot has also been drawn so that it is understood that the results obtained in the new method are accurate. Several real life examples and their analysis have been discussed with graph to demonstrate the potential of the proposed method. The results obtained show that the proposed method has given good results. In the case of outlier, the proposed method and the box plot method have shown similar results. Primary advantage of this new procedure is that it is not as expensive as neural networks, and genetic algorithms. 展开更多
关键词 Fuzzy Set Membership function Five number Summary OUTLIERS
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部分Motzkin路的计数
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作者 杨胜良 王楠 《兰州理工大学学报》 CAS 北大核心 2024年第3期137-142,共6页
一条长为n的部分Motzkin路是从(0,0)到(n,k)的一条经过整点的格路径,它由上步U=(1,1),下步D=(1,-1)以及水平步H=(1,0)构成,且从不走到x轴的下方.从(0,0)到(n,0)的Motzkin路的个数叫做第n个Motzkin数.利用核方法得到了Motzkin数的发生函... 一条长为n的部分Motzkin路是从(0,0)到(n,k)的一条经过整点的格路径,它由上步U=(1,1),下步D=(1,-1)以及水平步H=(1,0)构成,且从不走到x轴的下方.从(0,0)到(n,0)的Motzkin路的个数叫做第n个Motzkin数.利用核方法得到了Motzkin数的发生函数及部分Motzkin路径数的Riordan矩阵的表示.基于递推关系和线性代数方法给出了高度受限的部分Motzkin路的发生函数,并给出了相关示例. 展开更多
关键词 Motzkin路 部分Motzkin路 Motzkin数 发生函数 核方法
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基于GBM算子的不平衡概率语言Z-number多属性群决策
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作者 陈向 张晓珍 +1 位作者 刘嘉俊 毛军军 《高师理科学刊》 2023年第3期14-20,共7页
Z-number作为一种有效的信息表达方式,能够很好的描述带有不确定信息的自然语言.但大多数关于Z-number的研究依赖于均匀分布的语言术语集,并且用于聚合Z-number信息的聚合算子很少能够考虑属性之间的关系.提出一种非均匀分布的语言尺度... Z-number作为一种有效的信息表达方式,能够很好的描述带有不确定信息的自然语言.但大多数关于Z-number的研究依赖于均匀分布的语言术语集,并且用于聚合Z-number信息的聚合算子很少能够考虑属性之间的关系.提出一种非均匀分布的语言尺度函数,讨论了概率语言Z-number在不平衡语义下的情形,运用定义的新型算子对于概率语言Z-number进行聚合.定义相关运算以及得分函数,构建多目标线性优化模型确定最佳投资比例.通过实例说明了所提出方法的可行性与有效性,并进行了灵敏度分析. 展开更多
关键词 多属性群决策 Z-number Bonferroni几何平均算子 得分函数
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基于指数函数的川滇地区余震序列衰减规律研究
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作者 徐世达 段俊康 +3 位作者 何本国 刘佳奇 鲍泽铭 陈天晓 《地震工程学报》 CSCD 北大核心 2024年第1期207-213,共7页
较大的余震可能造成额外损失并有二次触发建筑物受灾的风险。为研究余震序列衰减规律,文章尝试采用指数衰减模型拟合分析5个不同地区余震序列,并借助修正赤池信息准则、贝叶斯信息准则与调整后R^(2),分析其与传统余震衰减模型的性能。... 较大的余震可能造成额外损失并有二次触发建筑物受灾的风险。为研究余震序列衰减规律,文章尝试采用指数衰减模型拟合分析5个不同地区余震序列,并借助修正赤池信息准则、贝叶斯信息准则与调整后R^(2),分析其与传统余震衰减模型的性能。结果表明,指数模型描述余震序列衰减规律的能力与修正的大森余震模型、修正的拉伸指数模型接近。尤其对于四川长宁M_(S)6.0余震序列和云南彝良M_(S)5.7余震序列,指数模型表现优于其他两种模型。指数模型参数具有明确的物理意义:参数A与r之和能够准确代表强震后的实际初始余震数,5个余震序列初始余震数偏差均小于1.70%;参数k可作为反映余震序列衰减快慢的特征值,k值越大则余震序列衰减越慢,其值与主震震级呈反比例关系。 展开更多
关键词 余震序列 指数函数 初始余震数 衰减
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包含广义调和数的级数之和
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作者 黄永忠 雷冬霞 《大学数学》 2024年第3期62-69,共8页
利用p级数的解析延拓,给出相应于广义调和数与zeta函数之差的几个级数的和,并给出几个应用例子;对包含收敛p级数余项的一个级数,给出其和的计算式子.
关键词 广义调和数 级数的和 ZETA函数 P级数
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Corresponding Prime Number Distribution Equation 被引量:1
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作者 Dan Liu Chenglong Liu 《Journal of Applied Mathematics and Physics》 2023年第11期3354-3365,共12页
The conjecture of twin prime numbers is a mathematical problem. Proving the twin prime conjecture using traditional modern number theory is extremely profound and complex. We propose an elementary research method for ... The conjecture of twin prime numbers is a mathematical problem. Proving the twin prime conjecture using traditional modern number theory is extremely profound and complex. We propose an elementary research method for corresponding prime number, proved that the conjecture of twin prime numbers and obtain the corresponding prime distribution equation. According to the distribution rate of corresponding prime numbers, the distribution pattern of twin prime numbers was proved the distribution rate theorem. This is the distribution rate of prime numbers corresponding to composite numbers, which approaches the distribution rate of prime numbers corresponding to integers. Based on the corresponding prime distribution equation, obtain the twin prime inequality function. Then, the formula for calculating twin prime numbers was discussed. There is also the Hardy Littlewood conjecture. This provides a practical and feasible approach for studying the distribution of twin prime numbers. 展开更多
关键词 Prime number Composite number Twin Prime numbers Corresponding Prime Distribution Equation Twin Prime Inequality function
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基于非负矩阵分解的函数型聚类算法改进与比较
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作者 王丙参 魏艳华 李旭 《统计与决策》 北大核心 2024年第15期46-52,共7页
非负函数型数据可以不等间隔观测,在理论和实践中应用广泛,对其进行聚类可以更好地探索客观规律。文章利用位置积分变换将函数型数据转化为高维向量,再通过非负矩阵分解(NMF)将其转化为低维向量,以此构建函数型聚类算法。针对基于NMF的... 非负函数型数据可以不等间隔观测,在理论和实践中应用广泛,对其进行聚类可以更好地探索客观规律。文章利用位置积分变换将函数型数据转化为高维向量,再通过非负矩阵分解(NMF)将其转化为低维向量,以此构建函数型聚类算法。针对基于NMF的函数型谱聚类算法,给出了确定聚类个数K的两种方法:一种是根据Laplacian矩阵的特征值确定K;另一种是构建新评价指标,通过搜索确定K。数值实验结果显示:基于位置积分变换和NMF的函数型聚类算法有效,对函数结构要求宽松,但需限制函数取值为正;NMF的秩可通过cophenetic相关系数确定,建议取较小的值,以剔除类的冗余特征。在确定谱聚类的聚类个数K时,建议对降维后的数据进行标准化处理,以缩小样本间的距离变化范围;聚类个数变点图直观有效,再结合特征值差分法确定K很有参考价值,建议阈值取[0.05,0.08];根据吻合度与相似比确定K的方法有效且简单易懂。 展开更多
关键词 函数型数据 非负矩阵分解 谱聚类 聚类个数
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基于中国剩余定理的NFC安全认证算法 被引量:1
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作者 邹同浩 《计算机应用与软件》 北大核心 2024年第1期322-327,共6页
针对近场通信技术在应用中出现的安全隐患问题,给出一种基于中国剩余定理的算法。算法利用中国剩余定理实现对传送信息进行加密,中国剩余定理基于数学中大素数分解难题,使得攻击者无法进行破解;所有信息加密过程中混入随机数,用于保证... 针对近场通信技术在应用中出现的安全隐患问题,给出一种基于中国剩余定理的算法。算法利用中国剩余定理实现对传送信息进行加密,中国剩余定理基于数学中大素数分解难题,使得攻击者无法进行破解;所有信息加密过程中混入随机数,用于保证消息的新鲜性;算法在进行信息更新时采用伪随机函数计算,因伪随机函数具备的单向性,使得攻击者无法分析出有用隐私信息。将不同算法对比安全分析,表明该算法能够抵抗重放攻击、异步攻击等多种攻击。通过性能角度及仿真实验对多个算法进行分析,结果表明该算法计算时间复杂度低于其他算法。 展开更多
关键词 近场通信 中国剩余定理 伪随机函数 大素数 安全认证 GNY逻辑形式化分析
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具有疫苗接种和潜伏期的传染病模型的最优控制分析
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作者 豆中丽 王锐 《东北师大学报(自然科学版)》 CAS 北大核心 2024年第2期36-42,共7页
建立了具有疫苗接种和潜伏期的传染病最优控制模型,得到了基本再生数R_(0),构造了Lyapunov函数.当R_(0)<1时,无病平衡点是全局渐近稳定的;当R_(0)>1时,地方病平衡点是全局渐近稳定的.利用最优控制理论和Pontryagin原理分析了最优... 建立了具有疫苗接种和潜伏期的传染病最优控制模型,得到了基本再生数R_(0),构造了Lyapunov函数.当R_(0)<1时,无病平衡点是全局渐近稳定的;当R_(0)>1时,地方病平衡点是全局渐近稳定的.利用最优控制理论和Pontryagin原理分析了最优控制策略,使得疾病控制过程中的成本最低.用数值模拟验证了理论结果的正确性. 展开更多
关键词 基本再生数 LYAPUNOV函数 全局稳定性 最优控制 Pontryagin原理
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Picture模糊数的改进得分函数在多属性群决策中的应用
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作者 吴孝宇 郑婷婷 +1 位作者 刘钧歌 孟伟伟 《安徽大学学报(自然科学版)》 CAS 北大核心 2024年第3期15-24,共10页
针对picture模糊环境下专家权重和属性权重信息未知的多属性群决策问题进行研究.首先,针对现有picture模糊数的得分函数存在一些不足问题,提出了一种新的得分函数.通过分析其相关性质,并与现有得分函数进行比较,说明其更具合理性,能更... 针对picture模糊环境下专家权重和属性权重信息未知的多属性群决策问题进行研究.首先,针对现有picture模糊数的得分函数存在一些不足问题,提出了一种新的得分函数.通过分析其相关性质,并与现有得分函数进行比较,说明其更具合理性,能更好地处理模糊决策信息.其次,提出了基于得分函数的picture模糊环境下的多属性群决策方法,根据每位专家给出的picture模糊评价信息的不精确程度及不同专家给出信息的差异程度,从个体和群体两方面综合得到决策者权重;利用得分函数构造不同属性的灰靶贡献度,从而确定属性权重.最后,通过实例比较分析验证了所提方法的可行性和有效性. 展开更多
关键词 picture模糊集 picture模糊数 得分函数 多属性群决策
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熔融温度对DLC薄膜杂化状态影响的分子动力学研究
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作者 罗宏博 杨来东 +2 位作者 连潇 王建吉 朱砚 《真空科学与技术学报》 CAS CSCD 北大核心 2024年第3期266-271,共6页
文章基于Tersoff势函数,采用分子动力学方法建立金刚石的分子模型,分析了不同熔融温度和冷却过程对原子键合结构,径向分布函数曲线和配位数的影响,从原子尺度阐明了DLC薄膜制备过程中原子形态杂化的形成机理。研究发现:DLC薄膜主要由C-... 文章基于Tersoff势函数,采用分子动力学方法建立金刚石的分子模型,分析了不同熔融温度和冷却过程对原子键合结构,径向分布函数曲线和配位数的影响,从原子尺度阐明了DLC薄膜制备过程中原子形态杂化的形成机理。研究发现:DLC薄膜主要由C-sp3和C-sp2杂化相组成,当温度低于6000 K时,熔融和冷却基本不会使C-sp3杂化发生结构转变,薄膜的性能比较稳定。当温度高于7000 K时,熔融过程中有大量的C-sp3杂化原子转变为C-sp2和C-sp1,冷却和弛豫平衡会引起高能态C-sp3杂化原子转变为C-sp2,但C-sp1杂化的含量基本不变。熔融温度主要影响DLC薄膜制备过程中C-sp3和C-sp2相的百分比含量,当体系中C-sp2含量超过40%,薄膜的性能将趋向于石墨。 展开更多
关键词 分子动力学 熔融温度 径向分布函数 配位数 类金刚石 杂化
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