检索结果-南通市图书馆

Some remarks on invertible substitutions on three letter alphabet

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1999年第19期44卷 1755-1760页

作者： zhixiong wen Yiping Zhang Wuhan Univ Dept Math State Key Lab Software Engineer Wuhan 430072 Peoples R China

By introducing the notion of 'prime substitution' it is shown that the set of invertible substitutions over an alphabet of more than three letters is not finitely generated. Some examples are given.

关键词： invertible substitution prime substitution.

A Property of m-Tuplings Morse Sequence

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2006年第3期11卷 473-476页

作者： NIU Min wen zhixiong Department of Mathematics and Mechanics University of Science and Technology Beijing Beijing 100083 China School of Mathematics and Statistics Wuhan University Wuhan 430072 Hubei China

The m-tuplings Morse sequence, as a fixed point of a constant length substitution, was discussed. An equivalent definition was given by the property of the m-adie development of the integers. Using the combinatorial properties of the m-tuplings Morse sequence, we mainly obtain this sequenee is an admissible sequence and the other two sequenees generated by it are also admissible sequences, which extends the conclusion that the Thue-Morse sequence is an admissible sequences.

关键词： m-tuplings Morse sequence admissible sequence Thue-Morse sequence

层状复合夹煤岩石组合体试样强度试验与破坏特征研究

在线全文

学校读者我要写书评

暂无评论

实验技术与管理 2024年第4期41卷 9-14页

作者：石建军贾明琦冯吉成苏士杰张建伟闻志雄吉志海牛格轩华北科技学院矿山安全学院河北廊坊065201 中天合创能源有限责任公司内蒙古鄂尔多斯017317

针对巷道复合夹煤组合结构顶板易冒落问题,以某矿取芯和钻孔窥视探测获得的巷道层状复合夹煤顶板结构组合类型为实验背景,对砂质泥岩、中砂岩以及煤厚度为20、30、40 mm不同结构组合类型的复合试件进行了单轴压缩试验,研究了复合夹煤岩... 详细信息

针对巷道复合夹煤组合结构顶板易冒落问题,以某矿取芯和钻孔窥视探测获得的巷道层状复合夹煤顶板结构组合类型为实验背景,对砂质泥岩、中砂岩以及煤厚度为20、30、40 mm不同结构组合类型的复合试件进行了单轴压缩试验,研究了复合夹煤岩石组合体的力学特性与破坏特征。试验结果表明:复合夹煤岩石组合体的抗压强度均小于单一岩石,中砂岩夹煤厚度为30mm时抗压强度达到单一中砂岩抗压强度的85.95%,抗压强度随着煤厚变薄而下降;砂质泥岩夹煤厚度为20 mm时仅为单一砂质泥岩抗压强度的32.5%,随着夹煤厚度增加抗压强度也增大,夹煤厚度超过30mm后抗压强度增大不明显。复合夹煤岩石组合体整体呈X状共轭斜面剪切破坏、单斜面剪切破坏、部分拉伸破坏,随着复合夹煤岩石组合类型不同呈现不同的破坏特征等。

关键词：层状复合顶板复合夹煤岩石组合体单轴压缩力学特性破坏特征

The influence of Lactobacillus plantarum fermentation in selenium-enriched Brassica napus L.:changes in the nutritional constituents,bioactivities and bioaccessibility

在线全文

学校读者我要写书评

暂无评论

Oil Crop Science 2024年第2期9卷 81-90页

作者： wen Wang zhixiong He Ruiying Zhang Min Li Zhenxia Xu Xia Xiang Oil Crops Research Institute Chinese Academy of Agricultural SciencesOil Crops and Lipids Process Technology National&Local Joint Engineering LaboratoryKey Laboratory of Oilseeds ProcessingMinistry of Agriculture and Rural AffairsHubei Key Laboratory of Lipid Chemistry and NutritionWuhan 430062China

Selenium(Se)-enriched Brassica napus *** a valuable organic Se *** this study,the fermentation broth enriched with organic Se(FFS)was prepared using Lactobacillus plantarum to ferment the substrate of Se-enriched Brassica napus *** increases were observed after fermentation in total sugars,reducing sugars,soluble proteins,total phenolic content(TPC),and total flavonoid content(TFC).The organic Se was retained at a concentration of 54.75 mg/g in the freeze-dried *** component analysis and cluster analysis showed good separation between the FFS and unfermented(FS)*** 2-ethyloxetane had the highest content among all volatiles,while sinapine had the highest content among all phenolic *** fermentation process showed remarkable improvement in the abundance and concentration of volatile compounds and phenolic contents,making FFS exhibit strong antioxidant activity and inhibitory capacity againstα-glucosidase *** bioaccessibility of phenolic compounds was significantly greater in FFS compared to *** analysis revealed that the majority of phenolic compounds contained in FFS did not exhibit mutagenicity toxicity,hepatotoxicity,skin sensitization,or blood-brain barrier penetration,indicating a favorable level of ***,our study provides a new insight into the further utilization of Se-enriched Brassica napus *** foods.

关键词： Se-enriched Brassica napus L. Fermentation Antioxidant activity Inhibitory activity Bioaccessibility

Dimensions of modified Besicovitch-Eggleston sets

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2006年第2期49卷 245-254页

作者： XIE Yuqiong & wen zhixiong Department of Mathematics, Wuhan University of Technology, Wuhan 430070, China School of Mathematics and Statistics, Wuhan University, Wuhan 430072, China Department of Mathematics Wuhan University of Technology Wuhan China School of Mathematics and Statistics Wuhan University Wuhan China

We consider the variants of Besicovitch-Eggleston sets in symbolic spaces, and determine their fractal dimensions.

关键词： Besicovitch-Eggleston set fractal dimension symbolic space multifractal.

THE STRUCTURE OF INVERTIBLE SUBSTITUTIONS ON A THREE-LETTER ALPHABET

在线全文

学校读者我要写书评

暂无评论

Analysis in Theory and Applications 2003年第4期19卷 365-382页

作者： Tan Bo wen zhixiong Zhang Yiping (Wuhan University,China) Wuhan University China

We study the structure of invertible substitutions on three-letter alphabet. We show that there exists a finite set S of invertible substitutions such that any invertible substitution can be written as I wσ 1σ 2…σ k,where I w is the inner automorphism associated with w, and σ j∈ S for 1≤j≤k. As a consequence,M is the matrix of an invertible substitution if and only if it is a finite product of non-negative elementary matrices.

关键词： invertible substitution indecomposable substitution combinatorics of words