Comparison of K_(IC) Values for SiC Whisker Reinforced Ceramic Composites Obtained by Using Various Methods

The fracture toughness (KIC) values determined by indentation microfracture method (IM ) for SiC whisker reinforced Al2O3 and ZrO2 based composites were calculated with different IM equations and compared with those obtained by singte edge notched beam (SENB) technique. Experimental results show that the KIC (IM) values calculated with different equations are quite different one from another. For composites without phase transformable components the KIC (IM) and KIC (SENB) values are practically on the same level, but for composites with phase transformable components (partially stabilized zirconia) the KIC (SENB) values are always higher than KIC (IM). This is because that the IM method can not reveal sensitively the toughening effect due to dynamic t-m transformation of ZrO2 as the SENB method does. The accuracy of the IM method depends on the Suitability of the IM equations and was evaluated for the materials used in this investigation. Two new IM equations are suggested with which the KIC (IM ) values can be obtained very close to KIC (SENB) values for composites having phase transformable components.

Value Composition and Optimal Utilization of Religious Cultural Landscape Resources

Multiple value structure of religious cultural landscape resources influences and determines development and regulation of cultural landscape resources. In the multiple value structure consisting of cultural inheritance, spiritual needs, industrial expansion, leisure and entertainment, development and utilization of religious cultural landscape resources should adhere to scientific classification, relatively independent policy orientation, make and implement specific countermeasures, so as to meet various requirements of the public and other relevant subjects using more refined and improved policy measures, and to realize the optimal utilization and comprehensive value of religious cultural landscapes.

INTERSECTION POINT RULE OF THE RETENTION VALUE AND MOBILE PHASE COMPOSITION OF THE HOMOLOGUES IN REVERSED-PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY

Based on the intersection point rule of the retention value and normal boiling point of homologues in reversed-phase high-performance liquid chromatography(RPLC), the intersection point rule of the retention value of homologues and mobile phase composition has been derived, and was testified by a lot of experimental data from the literature. With this newly proposed equation, we can use the retention value of the compound in one mobile phase composition to predict its retention value in any other mobile phase composition. For fourteen groups of homologues in five mobile phase compositions on five Kinds of columns, the overall average absolute error of 721 data sets is 2.8%.

Composition of the Value of Tourism Creative Products under the Influence of Regional Culture

With the analysis of the influence of regional culture on the value of tourism creative products,the characteristics of the value of tourism creative products were studied,and the impact of regional culture on the composition and realization of the value was summarized. Thus, the general law of the influence of external factors on the product value could be drawn. Characteristics of the value of tourism creative products is contrasted to analyze the requirement motivation of consumers and to seek the ways of realization for products value with the influence of regional culture.The mathematical evaluation model was employed for evidence.Based on the model,the influencing factors of the value of different types of creative products were explored, which would provide theories and enlightenment for the co-creation and appreciation of creative products in the future.

Analysis on the Value Composition and Epochal Connotation of Sports Culture

Along with our country society＇ s unceasing development, our country national＇ s living standard obtains the enhancement gradually. But inherited and brings honor to the sports culture also to become our country to develop the sports enterprise the most important, the sports culture impels also strengthened our country＇ s promotion of cultural and ethical progress, improved national＇ s physical quality and the thought idea, to carried forward the sports spirit and the enhancement nationality sentiment has the vital role. Moreover, the sports culture inheritance and the development also promoted our country＇ s sports enterprise development. This article discusses our country sports culture value with emphasis the construction and the time connotation.

Dynamic Evolution of NDVI in Qinling Mountains from 2000 to 2019

[Objectives]To investigate the dynamic evolution of vegetation index in Qinling Mountains from 2000 to 2019.[Methods]Based on MODIS13 NDVI data,the regularity of dynamics of vegetation index in Qinling Mountains from 2000 to 2019 was analyzed using maximum value composite method and trend analysis method.[Results]The NDVI in Qinling Mountains was in the range of 0.799-0.863 during 2000-2019.It showed a slow upward trend overall,and the growth rate was 0.033/(10 a).The area with declined NDVI accounted for 4.111%of the study area.It was distributed in the surrounding areas of cities,and was manly affected by the process of urbanization.The improved area accounted for 36.224%of the study area.It was widely distributed in Qinling Mountains,and was mainly affected by natural factors and national policies.[Conclusions]This study provides a basis for the protection of ecological environment and the sustainable development and utilization of resources in Qinling Mountains.