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INVERSE MATRIX AND PROPERTIES OF DOUBLE determinant.OVER QUATERNION FIELD

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Science China Mathematics 1991年第5期34卷 528-540页

作者：陈龙玄 Department of Mathematics Yantai University Yantai 264005 PRC

This paper is an extension of Ref. [1]. Here we study the properties of double determi-nant over quaternion field. The necessary and sufficient existence condition of inverse matrixand its direct expression have been ... 详细信息

关键词： quaternion field generalized unitary space double determinant.

A Compact determinant.l Representation for Inverse Difference

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Journal of Mathematical Research and Exposition 2000年第1期20卷 32-36页

作者：檀结庆合肥工业大学应用数学研究所 230009

A compact determinant.l representation for inverse difference is given. From the representation it is easy to know that the inverse difference of a function at some n + 1 points xo, x1, xn depends on th orderings of these points and it is locally independent of the permutation of first n - 1 points. Moreover we define reciprocal difference from another point of view, get the relation between inverse difference and reciprocal difference and obtain the property that the reciprocal difference is globally independent of the permutation of the points.

关键词： inverse difference reciprocal difference determinant.

Mutational analysis of the structure basis for the multimerization function of NifA central domain

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Science China(Life Sciences) 2001年第1期44卷 49-57页

作者：杨成涛俞冠翘 San-ChiunShen 沈善炯朱家璧 Laboratory of Molecular Genetics Shanghai Institute of Plant Physiology Chinese Academy of Sciences Shanghai 200032 China

In Klebsiella pneumoniae (Kp) NifA central domain, when theconservative amino acid residue Thr-290 in C3 region was replaced by Val, the function of NifA for activating the transcription of nif genes was lost. Thus the conservative Thr-290 residue seems critical for the activation function of NifA central domain. This point mutant of NifA central domain is used to examine the putative multimerization function of NifA central domain by merodiploid experiment. The results showed that the NifA central domain bore the multimerization determinant. of NifA protein. A series of truncated mutants of NifA were constructed to determine the structural elements at the central domain critical for multimerization. It demonstrates that amino acid residues 252-453 are involved in the multimerization function of NifA central domain.

关键词： NifA protein, central domain, multimerization determinant.

Oxidation of Pyridine Bases by Hydrogen Peroxide

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Journal of Chemistry and Chemical Engineering 2011年第1期5卷 82-88页

作者： Ali-zadeh Nahmad Islam Nagieva Inara Tofik Babaeva Badam Tofik Magerramov Abel Mamedali Nagiev Tofik Murtuza Nagiev Institute of Chemical Problems National Academy of Sciences of Azerbao＇an 29 H.Cavid Av. 370143 Baku AzerbaijaniRepublic Baku State University Azerbaoani Republic

The interfering kinetics of the coherent synchronous reactions of hydrogen peroxide decomposition and the oxidation of pyridine derivatives have been studied experimentally. The regions of the selective oxidation of the pyridine derivatives have been found, and the optimal conditions for the production of4-vynilpyridine, 4-vynilpyridine N-monoxide, 2, 2-dipyridyl, and pyridine have been determined. The most probable synchronization mechanism is suggested for hydrogen peroxide decomposition and the free-radical chain oxidation of pyridine derivatives. The HO2 -radical plays the key role in this mechanism. The activation energies are calculated for the elementary steps of 4-ethylpyridine dehydrogenation.

关键词： Free radical coherent synchronized conjugation N-monooxidation determinant.

Assessment of Household Food Security in the Face of Climate Change and Variability in the Upper Blue-Nile of Ethiopia

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Journal of Agricultural Science and Technology(B) 2017年第4期7卷 285-300页

作者： Abayineh Amare Belay Simane Centre for Environment and Development College of Development Studies Addis Ababa University Addis Ababa 1176 Ethiopia

It is widely recognized that climate variability and frequent droughts resulting from E1-Nino phenomenon are among the major risk factors affecting agricultural production that might contribute to hunger and food insecurity in East Africa in general and Ethiopia in particular. The objectives of the present study were to examine the food security status and determinant. of household food security among 442 randomly selected households in the Muger sub-basin of the Blue-Nile basin using household survey, focus group discussion （FGD） and key informant interview data collection methods. Both descriptive statistics （mean, chi-square test and t-test） and binary logit econometric model were used to analyze the data. The results showed that 57.8% of the households are food secure, while the remaining 42.2% of the households are food insecure. The binary logit regression results revealed that adoption of soil conservation, small-scale irrigation and employing different agronomic practices are important factors influencing household food security. Moreover, land holding and livestock ownership positively and significantly affected household＇s food security. The results further showed that family size and distance to the nearest market are important factors affecting food security in the inverse direction. The results highlighted careful investments on sustainable land management practices and small-scale irrigation that reduced sensitivity and increased the adaptive capacity of small_holder farmers to the adverse effect of climate change and variability. This study further highlighted the significance of livestock ownership and landholding in attaining food security under changing climate. The irmdings call for action based on advocacy family planning to curb population growth and invest in creating functional value-chain that help farmers＇ viable market for their produces.

关键词： Food security climate change drought determinant.

Coherent-Synchronized Oxidation of 4-Ethylpyridine and Piperidine by Hydrogen Peroxide

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Journal of Chemistry and Chemical Engineering 2013年第1期7卷 76-80页

作者： Ali-zadeh Nahmad Islam Nagieva Inara Tofik Nagiev Tofik Murtuza Nagiev Institute of Chemical Problems National Academy of Sciences of Azerbaijan 29 Baku 370143 Azerbaijani Republic Baku State University Azerbaijani Republic

The regions of the selective oxidation of the the production of 4-vinylpyridine, 4-vinylpyridine coherent-synchronized mechanism is suggested for 4-ethylpyridine and piperidine. The HO^＊2 radical plays 4-ethylpyridine and piperidine have been found, and the optimal conditions for N-monoxide and pyridine have been determined. The most probable hydrogen peroxide decomposition and the free-radical chain oxidation of the key role in this mechanism.

关键词： Coherent synchronized free-radical conjugation conjugated determinant.

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高等代数中有关问题的降价算法

高等学校计算数学学报 2005年第S1期 72-75页

作者：李敏东北财经大学数量经济系大连 116025

1 行列式值的计算求行列式值常用的计算方法[1]多种多样,但对高阶行列式计算很少有通用的公式．在计算机普及的条件下,公式法显得尤为重要,下面给出一种简单易行的公式法--降阶算法,它充分利用了二阶行列式计算简单、可以心算的特点,逐... 详细信息

1 行列式值的计算求行列式值常用的计算方法[1]多种多样,但对高阶行列式计算很少有通用的公式．在计算机普及的条件下,公式法显得尤为重要,下面给出一种简单易行的公式法--降阶算法,它充分利用了二阶行列式计算简单、可以心算的特点,逐次降阶而又不增子行列式计算的个数,减少了计算量又易于上机,从而提高了计算速度．

关键词： matrix determinant.