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On Some Mathematical Connections between the Cyclic Universe, Inflationary Universe, p-Adic Inflation, p-Adic Cosmology and Various Sectors of Number Theory
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作者 Michele Nardelli 《Journal of Modern Physics》 2024年第11期1869-1958,共90页
This paper is a review, a thesis, of some interesting results that have been obtained in various research concerning the “brane collisions in string and M-theory” (Cyclic Universe), p-adic inflation and p-adic cosmo... This paper is a review, a thesis, of some interesting results that have been obtained in various research concerning the “brane collisions in string and M-theory” (Cyclic Universe), p-adic inflation and p-adic cosmology. In Section 2, we have described some equations concerning cosmic evolution in a Cyclic Universe. In Section 3, we have described some equations concerning the cosmological perturbations in a Big Crunch/Big Bang space-time, the M-theory model of a Big Crunch/Big Bang transition and some equations concerning the solution of a braneworld Big Crunch/Big Bang Cosmology. In Section 4, we have described some equations concerning the generating ekpyrotic curvature perturbations before the Big Bang, some equations concerning the effective five-dimensional theory of the strongly coupled heterotic string as a gauged version of N=1five-dimensional supergravity with four-dimensional boundaries, and some equations concerning the colliding branes and the origin of the Hot Big Bang. In Section 5, we have described some equations regarding the “null energy condition” violation concerning the inflationary models and some equations concerning the evolution to a smooth universe in an ekpyrotic contracting phase with w>1. In Section 6, we have described some equations concerning the approximate inflationary solutions rolling away from the unstable maximum of p-adic string theory. In Section 7, we have described various equations concerning the p-adic minisuperspace model, zeta strings, zeta nonlocal scalar fields and p-adic and adelic quantum cosmology. In Section 8, we have shown various and interesting mathematical connections between some equations concerning the p-adic inflation, the p-adic quantum cosmology, the zeta strings and the brane collisions in string and M-theory. Furthermore, in each section, we have shown the mathematical connections with various sectors of Number Theory, principally the Ramanujan’s modular equations, the Aurea Ratio and the Fibonacci’s numbers. 展开更多
关键词 String Theory M-THEORY Cyclic Cosmology p-Adic and Adelic Analysis number Theory Ramanujan’s Modular Equations
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基于可靠性的疲劳试验数据处理方法
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作者 张凡 王丹 竺一峰 《舰船科学技术》 北大核心 2024年第12期8-12,共5页
本文基于疲劳可靠性的基本原理,在疲劳寿命对数正态分布的假设下,根据t分布理论,结合船舶及海洋工程一般构件具有95%置信度和97.72%可靠度下的P-S-N曲线的基本要求,推算出了具有95%置信度和误差限度5%内的疲劳试件个数与允许的最大变异... 本文基于疲劳可靠性的基本原理,在疲劳寿命对数正态分布的假设下,根据t分布理论,结合船舶及海洋工程一般构件具有95%置信度和97.72%可靠度下的P-S-N曲线的基本要求,推算出了具有95%置信度和误差限度5%内的疲劳试件个数与允许的最大变异系数数值对应关系,以此作为成组法疲劳试验的最少试件个数的判据开展典型节点的疲劳试验,得到具有95%置信度的百位估计值Np;并通过线性相关系数r判断对数疲劳应力Y=log S与X=log Np之间线性相关的程度,采用最小二乘法对对数疲劳寿命lg Np和对数疲劳应力lg S线性拟合,得到具有95%置信度的P-S-N曲线,并与IIW规范中相应的曲线进行对比分析,验证了本文试验方法的可行性和可靠性。 展开更多
关键词 试件个数 P-S-N曲线 变异系数 可靠度 置信度
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成组法疲劳试件个数选取方法研究
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作者 张凡 王艺陶 +1 位作者 王丹 竺一峰 《装备环境工程》 CAS 2024年第1期74-80,共7页
目的 在成组法疲劳试验过程中,确定最少疲劳试件个数判据,获取有效可靠的疲劳试验结果。方法基于疲劳可靠性的基本原理,在疲劳寿命对数正态分布的假设下,根据t分布理论,结合船舶及海洋工程一般构件具有95%置信度和可靠度p=97.72%下的P-... 目的 在成组法疲劳试验过程中,确定最少疲劳试件个数判据,获取有效可靠的疲劳试验结果。方法基于疲劳可靠性的基本原理,在疲劳寿命对数正态分布的假设下,根据t分布理论,结合船舶及海洋工程一般构件具有95%置信度和可靠度p=97.72%下的P-S-N曲线的基本要求,推算出相应置信度和可靠度下5%误差限度内的疲劳试件个数与允许的最大变异系数数值的对应关系,以此作为成组法疲劳试验最少试件个数的判据,开展典型节点的疲劳试验。结果 得到了具有95%置信度的百位估计值Np,并通过线性相关系数r,判断对数疲劳应力Y=lg S与X=lg Np之间线性相关的程度,采用最小二乘法对对数疲劳寿命lg Np和对数疲劳应力lg S进行线性拟合,得到了具有95%置信度的P-S-N曲线,与IIW规范中相应的曲线一致。结论 文中给出的成组法疲劳试验个数确定方法是合理、可靠的,为船舶与海洋工程结构物典型焊接接头成组法疲劳试验个数的确定提供了依据。 展开更多
关键词 试件个数 P-S-N曲线 变异系数 疲劳可靠性 成组法 疲劳试验 船舶结构
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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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基于Web of Science的精喹禾灵研究热点与趋势的可视化分析
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作者 杨丽莉 刘春光 +2 位作者 付海燕 宋新宇 杨峰山 《中国农学通报》 2024年第18期140-149,共10页
本研究旨在客观分析精喹禾灵(Quizalofop-p-ethyl)领域的研究现状,并揭示其研究前沿,以期为相关学者提供科学的数据参考。通过科学引文索引扩展版SCIE检索“Quizalofop-p-ethyl”,查到2007-2023年间181篇相关文献,并从中获取了精喹禾灵... 本研究旨在客观分析精喹禾灵(Quizalofop-p-ethyl)领域的研究现状,并揭示其研究前沿,以期为相关学者提供科学的数据参考。通过科学引文索引扩展版SCIE检索“Quizalofop-p-ethyl”,查到2007-2023年间181篇相关文献,并从中获取了精喹禾灵发文量、发文研究机构和作者等信息。借助Python和VOSviewer工具,进行了精喹禾灵研究领域关键词共现图谱的可视化分析。主要研究结果有:(1)精喹禾灵领域世界发文量和被引频次整体呈上升趋势,中国为发文量最多的国家,前10位世界发文量的研究机构大部分来自中国;(2)发文量最多的作者为美国的Webster EP,来自中国的研究机构篇均被引频次均较高;(3)研究热点主要聚集在降解和除草剂等方面。综上所述,中国在精喹禾灵研究领域处于领先地位,国内学者具有较强的研究实力和国际影响力。然而,近年来中国的发文量有所下降,面对日益深入的研究需求,中国需要持续努力以保持其领先优势。 展开更多
关键词 Web of Science 精喹禾灵 文献计量分析 趋势 可视化分析 研究现状 研究前沿 发文量 被引频次
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面向起重机械结构失效的疲劳故障诊断模型研究
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作者 赵鹏 罗惠龙 潘海林 《机械管理开发》 2024年第8期75-77,共3页
起重机在建筑工程中常被用于吊装重物,因此,在作业过程中,起重机的结构会受到相应磨损。为了对起重机机械结构的疲劳故障进行预测,以TKDLS400型号的起重机为研究对象,采用应力法对起重机不同结构的应力值进行检测,并根据应力值的大小和... 起重机在建筑工程中常被用于吊装重物,因此,在作业过程中,起重机的结构会受到相应磨损。为了对起重机机械结构的疲劳故障进行预测,以TKDLS400型号的起重机为研究对象,采用应力法对起重机不同结构的应力值进行检测,并根据应力值的大小和结构疲劳循环次数之间的线性关系,构建了起重机的疲劳次数预测和剩余疲劳使用寿命模型。实验结果表明,起重机在滚筒处的疲劳使用次数剩余最短,仅剩5 356次,剩余使用寿命为11.6年,故此次研究的疲劳故障诊断模型具有一定的实用价值。 展开更多
关键词 起重机 机械结构 疲劳循环次数 剩余寿命 P-S-N曲线
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EMC单片机EM73P461A在工业中的应用
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作者 崔勤 李晔东 郑传文 《光电子技术》 CAS 2004年第1期46-50,共5页
EMC单片机 EM73P461 A是一款台湾产的基于 PIC内核的 4位单片机 ,文中介绍了它的一些功能及在工业中的应用 ,通过实际应用介绍了它的优缺点及在应用设计当中应该注意的问题。
关键词 单片机 EM73p461A 液晶驱动 应用 PIC
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Upper Bounds for Ramsey Numbers R(m,n,l) and R(m,n,l,s) with Parameter
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作者 黄益如 岳洪 张克民 《Journal of Shanghai University(English Edition)》 CAS 2003年第1期46-48,共3页
In the paper some new upper bounds with parameters were obtained for the classical Ramsey numbers R(m,n,l) and R(m,n,l,s) . By using the upper bounds, it was proved that R (4,4,4)≤236.
关键词 Ramsey number (m n l p) graph Ramsey graph.
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The Generalized <i>r</i>-Whitney Numbers
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作者 B. S. El-Desouky F. A. Shiha Ethar M. Shokr 《Applied Mathematics》 2017年第1期117-132,共16页
In this paper, we define the generalized r-Whitney numbers of the first and second kind. Moreover, we drive the generalized Whitney numbers of the first and second kind. The recurrence relations and the generating fun... In this paper, we define the generalized r-Whitney numbers of the first and second kind. Moreover, we drive the generalized Whitney numbers of the first and second kind. The recurrence relations and the generating functions of these numbers are derived. The relations between these numbers and generalized Stirling numbers of the first and second kind are deduced. Furthermore, some special cases are given. Finally, matrix representation of the relations between Whitney and Stirling numbers is given. 展开更多
关键词 Whitney numberS r-Whitney numberS p-Stirling numberS GENERALIZED q-Stirling numberS GENERALIZED STIRLING numberS
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Factorization Numbers of a Class of Finite p-groups
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作者 WANG Yu-lei ZHANG Yuan-feng GUO Peng 《Chinese Quarterly Journal of Mathematics》 2018年第4期434-440,共7页
Let p be a prime number and f_2(G) be the number of factorizations G = AB of the group G, where A, B are subgroups of G. Let G be a class of finite p-groups as follows,G = a, b | a^(p^n)= b^(p^m)= 1, a^b= a^(p^(n-1)+1... Let p be a prime number and f_2(G) be the number of factorizations G = AB of the group G, where A, B are subgroups of G. Let G be a class of finite p-groups as follows,G = a, b | a^(p^n)= b^(p^m)= 1, a^b= a^(p^(n-1)+1), where n > m ≥ 1. In this article, the factorization number f_2(G) of G is computed, improving the results of Saeedi and Farrokhi in [5]. 展开更多
关键词 finite P-GROUP FACTORIZATION number SUBGROUP COMMUTATIVITY DEGREE
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ON THE STRONG LAW OF LARGE NUMBERS
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作者 邱德华 甘师信 《Acta Mathematica Scientia》 SCIE CSCD 2005年第3期525-532,共8页
This paper introduces the concept of BC sequences and investigates some conditions which imply the strong law of large numbers for these sequences. The authors also study the strong law of large numbers for general ra... This paper introduces the concept of BC sequences and investigates some conditions which imply the strong law of large numbers for these sequences. The authors also study the strong law of large numbers for general random variable sequences. As applications of the result the authors characterize p-smoothableness of Banach space. Some generalizations of Petrov theorem, the Marcinkiewicz-Zygmund theorem and Hoffmann-J(?)rgensen and Pisier theorem are obtained. 展开更多
关键词 BC random variable sequence p-smoothable Banach space the strong law of large numbers
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A MODEL FOR WHITE NOISE ANALYSIS IN P-ADIC NUMBER FIELDS
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作者 黄志远 《Acta Mathematica Scientia》 SCIE CSCD 1996年第1期1-14,共14页
We propose a simple model for white noise analysis in the p-adic case based on the p-adic analogue of the space L(2)(R(infinity), d mu).
关键词 white noise analysis p-adic numbers non-Archimedean norm Gaussian distribution generalized functional chaotic representation
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On the Strong Law of Large Numbers for Non-Independent B-Valued Random Variables
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作者 GanShi-xin 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第1期13-17,共5页
This paper investigates some conditions which imply the strong laws of large numbers for Banach space valued random variable sequences. Some generalizations of the Marcinkiewicz-Zygmund theorem and the Hoffmann-J?rgen... This paper investigates some conditions which imply the strong laws of large numbers for Banach space valued random variable sequences. Some generalizations of the Marcinkiewicz-Zygmund theorem and the Hoffmann-J?rgensen and Pisier theorem are obtained. Key words strong law of large numbers - Banach space valued random variable sequence - p-smoothable Banach space CLC number O 211.4 - O 211.6 Foundation item: Supported by the National Natural Science Foundation of China (10071058)Biography: Gan Shi-xin (1939-), male, Professor, research direction: martingale theory, probability limiting theory and Banach space geometry theory. 展开更多
关键词 strong law of large numbers Banach space valued random variable sequence p-smoothable Banach space
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On the Chromatic Number of (P5, C5, Cricket)-Free Graphs
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作者 Weilun Xu 《Engineering(科研)》 2022年第3期147-154,共8页
For a graph G, let be the chromatic number of G. It is well-known that holds for any graph G with clique number . For a hereditary graph class , whether there exists a function f such that holds for every has been wid... For a graph G, let be the chromatic number of G. It is well-known that holds for any graph G with clique number . For a hereditary graph class , whether there exists a function f such that holds for every has been widely studied. Moreover, the form of minimum such an f is also concerned. A result of Schiermeyer shows that every -free graph G with clique number has . Chudnovsky and Sivaraman proved that every -free with clique number graph is -colorable. In this paper, for any -free graph G with clique number , we prove that . The main methods in the proof are set partition and induction. 展开更多
关键词 P5-Free Graphs Chromatic number X-Boundedness
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The Generalization of Signed Domination Number of Two Classes of Graphs
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作者 Xia Hong Guoyan Ao Feng Gao 《Open Journal of Discrete Mathematics》 2021年第4期114-132,共19页
Let <img src="Edit_092a0db1-eefa-4bff-81a0-751d038158ad.png" width="58" height="20" alt="" /> be a graph. A function <img src="Edit_b7158ed5-6825-41cd-b7f0-5ab5e16... Let <img src="Edit_092a0db1-eefa-4bff-81a0-751d038158ad.png" width="58" height="20" alt="" /> be a graph. A function <img src="Edit_b7158ed5-6825-41cd-b7f0-5ab5e16fc53d.png" width="79" height="20" alt="" /> is said to be a Signed Dominating Function (SDF) if <img src="Edit_c6e63805-bcaa-46a9-bc77-42750af8efd4.png" width="135" height="25" alt="" /> holds for all <img src="Edit_bba1b366-af70-46cd-aefe-fc68869da670.png" width="42" height="20" alt="" />. The signed domination number <img src="Edit_22e6d87a-e3be-4037-b4b6-c1de6a40abb0.png" width="284" height="25" alt="" />. In this paper, we determine the exact value of the Signed Domination Number of graphs <img src="Edit_36ef2747-da44-4f9b-a10a-340c61a3f28c.png" width="19" height="20" alt="" /> and <img src="Edit_26eb0f74-fcc2-49ad-8567-492cf3115b73.png" width="19" height="20" alt="" /> for <img src="Edit_856dbcc1-d215-4144-b50c-ac8a225d664f.png" width="32" height="20" alt="" />, which is generalized the known results, respectively, where <img src="Edit_4b7e4f8f-5d38-4fd0-ac4e-dd8ef243029f.png" width="19" height="20" alt="" /> and <img src="Edit_6557afba-e697-4397-994e-a9bda83e3219.png" width="19" height="20" alt="" /> are denotes the <em>k</em>-th power graphs of cycle <img src="Edit_27e6e80f-85d5-4208-b367-a757a0e55d0b.png" width="21" height="20" alt="" /> and path <img src="Edit_70ac5266-950b-4bfd-8d04-21711d3ffc33.png" width="18" height="20" alt="" />. 展开更多
关键词 Signed Domination Function Signed Domination numbers Graphs Cn style="margin-left:-7px ">k Graphs Pn style="margin-left:-7px ">k
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Polysurfacic Tori or Kideas Inspired by the Möbius Strip Topology
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作者 Emmanuel Cadier Anaxhaoza 《Advances in Pure Mathematics》 2023年第9期543-551,共9页
Polysurfacic tori or kideas are three-dimensional objects formed by rotating a regular polygon around a central axis. These toric shapes are referred to as “polysurfacic” because their characteristics, such as the n... Polysurfacic tori or kideas are three-dimensional objects formed by rotating a regular polygon around a central axis. These toric shapes are referred to as “polysurfacic” because their characteristics, such as the number of sides or surfaces separated by edges, can vary in a non-trivial manner depending on the degree of twisting during the revolution. We use the term “Kideas” to specifically denote these polysurfacic tori, and we represent the number of sides (referred to as “facets”) of the original polygon followed by a point, while the number of facets from which the torus is twisted during its revolution is indicated. We then explore the use of concave regular polygons to generate Kideas. We finally give acceleration for the algorithm for calculating the set of prime numbers. 展开更多
关键词 Heavenly Things Topology Euclidian Geometry Möbius Strip Emmanuel’s Tori YiBoLong’s Tori Cadier’s Tori Möbius Tori Polysurfacic Tori Kideas The Keys KideaCross KideaStar Churros Algorithm for Calculating the Set of Prime numbers P The Last Found Element of P
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Some Implications of the Gessel Identity
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作者 Claire Levaillant 《Applied Mathematics》 2023年第9期545-579,共35页
We generalize the congruences of Friedmann-Tamarkine (1909), Lehmer (1938), and Ernvall-Metsänkyla (1991) on the sums of powers of integers weighted by powers of the Fermat quotients to the next Fermat quotient p... We generalize the congruences of Friedmann-Tamarkine (1909), Lehmer (1938), and Ernvall-Metsänkyla (1991) on the sums of powers of integers weighted by powers of the Fermat quotients to the next Fermat quotient power, namely to the third power of the Fermat quotient. Using this result and the Gessel identity (2005) combined with our past work (2021), we are able to relate residues of some truncated convolutions of Bernoulli numbers with some Ernvall-Metsänkyla residues to residues of some full convolutions of the same kind. We also establish some congruences concerning other related weighted sums of powers of integers when these sums are weighted by some analogs of the Teichmüller characters. 展开更多
关键词 Convolutions Involving Bernoulli numbers Truncated Convolutions Involving Bernoulli numbers CONGRUENCES Binomial and Multinomial Convolutions of Divided Bernoulli numbers Multiple Harmonic Sums Generalized Harmonic numbers Miki Identity Gessel Identity Sums of Powers of Integers Weighted by Powers of the Fermat Quotients Generalization of Kummer’s Congruences Generalizations of Friedmann-Tamarkine Lehmer Ernvall-Metsänkyla’s Congruences p-Adic numbers Weighted Sums of Powers of Integers
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太湖梅梁湾春季浮游植物初级生产力 被引量:21
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作者 张运林 秦伯强 +2 位作者 陈伟民 陈宇炜 高光 《湖泊科学》 EI CAS CSCD 北大核心 2005年第1期81-86,共6页
用黑白瓶测氧法对梅梁湾春季浮游植物初级生产力的变化特征进行研究,探讨了初级生产力的日变化、垂直变化、区域分布、浮游植物现存量与初级生产力的关系以及不同曝光时间对P-I曲线的影响.结果表明,梅梁湾浮游植物初级生产力存在明显的... 用黑白瓶测氧法对梅梁湾春季浮游植物初级生产力的变化特征进行研究,探讨了初级生产力的日变化、垂直变化、区域分布、浮游植物现存量与初级生产力的关系以及不同曝光时间对P-I曲线的影响.结果表明,梅梁湾浮游植物初级生产力存在明显的日变化,最大值出现在10:00-14:00;初级生产力在梅梁湾分布呈现为从湾内向湾口逐渐递减的趋势;除表层水受光抑制影响使其生产力相对较低外,初级生产力随水深的增加而降低;初级生产力与叶绿素a存在显著的正相关,用水柱层平均叶绿素a浓度来估算初级生产力比用表层叶绿素a浓度来估算要更为精确;短的曝光时间往往带来高的初级生产力和同化系数. 展开更多
关键词 初级生产力 春季 日变化 浮游植物 区域分布 垂直变化 光抑制 梅梁湾 太湖 叶绿素A浓度
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不同氮磷比例营养液对AM真菌生长发育的影响 被引量:15
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作者 陈宁 王幼珊 +4 位作者 杨延杰 林多 仇宏伟 倪小会 张美庆 《植物营养与肥料学报》 CAS CSCD 北大核心 2007年第1期143-147,共5页
温室条件下,研究不同氮磷比例营养液对丛枝菌根(Arbuscular mycorrhizae,AM)真菌(Glomus mosseae)生长发育的影响。结果表明:在一定磷水平条件下增加氮的水平,有利于菌根真菌的生长发育,但超过一定水平则会抑制菌根真菌的生长发育,说明... 温室条件下,研究不同氮磷比例营养液对丛枝菌根(Arbuscular mycorrhizae,AM)真菌(Glomus mosseae)生长发育的影响。结果表明:在一定磷水平条件下增加氮的水平,有利于菌根真菌的生长发育,但超过一定水平则会抑制菌根真菌的生长发育,说明氮水平也会影响菌根真菌的生长发育,这种影响与氮磷比例有关。综合比较菌根长度、根外菌丝量及孢子数三项指标,在20%浓度Hoagland营养液的基础上,将氮磷比例提高到4∶2有利真菌生长。在AM菌剂生产中,通过营养液中氮磷比例的调控能获得较大数量的侵染根段、菌丝及孢子等繁殖体。 展开更多
关键词 氮磷比例 侵染率 菌丝量 孢子数 AM菌剂
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腐蚀磨损协同作用率的研究 被引量:19
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作者 赵国鹏 于欣伟 +2 位作者 吴荫顺 顾正秋 朱日彰 《摩擦学学报》 EI CAS CSCD 北大核心 1998年第2期157-161,共5页
提出了腐蚀与磨损“协同作用率”的概念,并用于判断腐蚀与磨损协同作用的性质及大小和确定腐蚀磨损过程中材料损失的主要形式.介绍了协同作用率的测定方法,并以G105钢及化学镀Ni-P合金在5.0%NaCl溶液中的腐蚀磨损作... 提出了腐蚀与磨损“协同作用率”的概念,并用于判断腐蚀与磨损协同作用的性质及大小和确定腐蚀磨损过程中材料损失的主要形式.介绍了协同作用率的测定方法,并以G105钢及化学镀Ni-P合金在5.0%NaCl溶液中的腐蚀磨损作为研究对象,研究了载荷、滑动速度对腐蚀磨损协同作用的影响.结果表明:协同作用率随载荷增大而增大,随滑动速度增大而减小. 展开更多
关键词 腐蚀磨损 协同作用率 G105钢 化学镀 NI-P合金
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