The fractal characteristics of tidal creeks in the Gaizhou Beach are analyzed based on high-resolution images fusionof Landsat TM and ERS2, and then the graphic models and characteristics of converse information tree ...The fractal characteristics of tidal creeks in the Gaizhou Beach are analyzed based on high-resolution images fusionof Landsat TM and ERS2, and then the graphic models and characteristics of converse information tree of tidalcreeks in the Gaizhou Beach are established. A calculation model is established based on the above results, and at thesame time, quantitative calculation of the evolution characteristics and the diversity between the northern and thesouthern parts of the Gaizhou Beach is carried out. By the supervised classification of these images, distribution andareas of high tidal flats, middle tidal flats and low tidal flats in the Gaizhou Beach are studied quantitatively, and imagecharactistics of seashell habitats in the Gaizhou Beach and the correlation between mudflat distribution and seashellhabitats are studied. At last, the engineering problems in the Gaizhou Beach are discussed.展开更多
Seashell has been applied as an indicator for ocean research and element analysis of the seashell is used to track biological or environmental evolution. In this work, laser-induced breakdown spectroscopy （LIBS） was...Seashell has been applied as an indicator for ocean research and element analysis of the seashell is used to track biological or environmental evolution. In this work, laser-induced breakdown spectroscopy （LIBS） was applied for elementary analysis of an ezo scallop-shell, and a graphite enrichment method was used as the assistance. It was found that LIBS signal intensity of Ca fluctuated less than 5%, in spite of the sampling positions, and Sr/Ca was related to the shell growth. A similar variation was also found when using a direct LIBS analysis on the shell surface, and it might be more practicable to track shell growth by investigating Sr/Ca ratio with Sr ionic line at 421.6 nm. The obtained results prove that calcium （Ca） is qualified as an internal reference for shell analysis, and LIBS is a potential analytical method for seashell study.展开更多
Cultivated for its richness in nutrients, tomato culture is demanding fertilizer, especially in calcium. Calcium deficiencies and physiological disorders cause serious diseases in tomatoes. Blossom end rot (BER), in s...Cultivated for its richness in nutrients, tomato culture is demanding fertilizer, especially in calcium. Calcium deficiencies and physiological disorders cause serious diseases in tomatoes. Blossom end rot (BER), in susceptible cultivars, may cause severe economic losses. The goal of this study is to determine the effect of three organic calcium sources on the growth and quality of fruit production of tomatoes. Egg, snail and sea shell powders and extracts have been used as biological fertilizers. The experiment was conducted in a block factorial trial with three replications. The trials comprised two factors: calcium sources and calcium source form (powder and extract). The results showed that the growth parameters and yield were improved by the calcium source, whatever the form. Also, BER was lower in plants treated with calcium contrary to the control. However, plants treated with eggshells showed the best growth (mean) and the lowest rate (0.40%) of BER than the snail and sea shell.展开更多
Cultivated for its richness in nutrients, tomato culture is demanding fertilizer, especially in calcium. Calcium deficiencies and physiological disorders cause serious diseases in tomatoes. Blossom end rot (BER), in s...Cultivated for its richness in nutrients, tomato culture is demanding fertilizer, especially in calcium. Calcium deficiencies and physiological disorders cause serious diseases in tomatoes. Blossom end rot (BER), in susceptible cultivars, may cause severe economic losses. The goal of this study is to determine the effect of three organic calcium sources on the growth and quality of fruit production of tomatoes. Egg, snail and sea shell powders and extracts have been used as biological fertilizers. The experiment was conducted in a block factorial trial with three replications. The trials comprised two factors: calcium sources and calcium source form (powder and extract). The results showed that the growth parameters and yield were improved by the calcium source, whatever the form. Also, BER was lower in plants treated with calcium contrary to the control. However, plants treated with eggshells showed the best growth (mean) and the lowest rate (0.40%) of BER than the snail and sea shell.展开更多
A vast majority of mollusks grow a hard shell for protection. The structure of these shells comprises several levels of hierarchy that increase their strength and their resistance to natural threats. This article focu...A vast majority of mollusks grow a hard shell for protection. The structure of these shells comprises several levels of hierarchy that increase their strength and their resistance to natural threats. This article focuses on nacreous shells, which are composed of two distinct layers. The outer layer is made of calcite, which is a hard but brittle material, and the inner layer is made of nacre, a tough and ductile material. The inner and outer layers are therefore made of materials with distinct structures and properties. In this article, we demonstrate that this system is optimum to defeat attacks from predators. A two-scale mod- eling and optimization approach was used. At the macroscale, a two-layer finite element model of a seashell was developed to capture shell geometry. At the microscale, a representative volume element of the microstructure of nacre was used to model the elastic modulus of nacre as well as a multiaxial failure criterion, both expressed as function of microstructural parameters. Experiments were also performed on actual shells of red abalone to validate the results obtained from simulations and gain insight into the way the shell fails under sharp perforation. Both optimization and experimental results revealed that the shell displays optimum performance when two modes of failure coincide within the structure. Finally, guidelines for designing two-layer shells were proposed to improve the performance of engineered protective systems undergoing similar structural and loading conditions.展开更多
This short essay focuses on just one of the mythological paintings of Evelyn Pickering De Morgan,Ariadne at Naxos of 1877 at The De Morgan Foundation(Figure 1).1 It consists of an iconographical and iconological analy...This short essay focuses on just one of the mythological paintings of Evelyn Pickering De Morgan,Ariadne at Naxos of 1877 at The De Morgan Foundation(Figure 1).1 It consists of an iconographical and iconological analysis of the ancient legend of Ariadne and Theseus,demonstrating Evelyn’s classical erudition and artistic mastery in visualizing a moment in the narrative,the desertion of Ariadne by Theseus on the beach at Naxos.展开更多
Marine CaCO3 skeletons have tailored architectures created by nature, which give them structural support and other functions. For example, seashells have dense lamellar structures, while coral, cuttlebone and sea urch...Marine CaCO3 skeletons have tailored architectures created by nature, which give them structural support and other functions. For example, seashells have dense lamellar structures, while coral, cuttlebone and sea urchin spines have interconnected porous structures. In our experiments, seashells, coral and cuttlebone were hydrothermaily converted to hydroxyapatite （HAP）, and sea urchin spines were converted to Mg-substituted tricalcium phosphate, while maintaining their original structures. Partially converted shell samples have mechanical strength, which is close to that of compact human bone. After implantation of converted shell and spine samples in rat femoral defects for 6 weeks, there was newly formed bone growth up to and around the implants. Some new bone was found to migrate through the pores of converted spine samples and grow inward. These results show good bioactivity and osteoconductivity of the implants, indicating the converted shell and spine samples can be used as bone defect fillers. The interconnected porous HAP scaffolds from converted coral or cuttlebone that have pore size larger than 100μm likely support infiltration of bone cells and vessels, and finally encourage new bone ingrowth.展开更多
基金This study was supported by the Project of“863”Marine Monitor of Hi-Tech Research and Development Program of China under contract No.2003AA604040.
文摘The fractal characteristics of tidal creeks in the Gaizhou Beach are analyzed based on high-resolution images fusionof Landsat TM and ERS2, and then the graphic models and characteristics of converse information tree of tidalcreeks in the Gaizhou Beach are established. A calculation model is established based on the above results, and at thesame time, quantitative calculation of the evolution characteristics and the diversity between the northern and thesouthern parts of the Gaizhou Beach is carried out. By the supervised classification of these images, distribution andareas of high tidal flats, middle tidal flats and low tidal flats in the Gaizhou Beach are studied quantitatively, and imagecharactistics of seashell habitats in the Gaizhou Beach and the correlation between mudflat distribution and seashellhabitats are studied. At last, the engineering problems in the Gaizhou Beach are discussed.
基金financially supported by National Natural Science Foundation of China(No.41506113)Natural Science Foundation of Shandong Province(No.ZR2014DP010)
文摘Seashell has been applied as an indicator for ocean research and element analysis of the seashell is used to track biological or environmental evolution. In this work, laser-induced breakdown spectroscopy （LIBS） was applied for elementary analysis of an ezo scallop-shell, and a graphite enrichment method was used as the assistance. It was found that LIBS signal intensity of Ca fluctuated less than 5%, in spite of the sampling positions, and Sr/Ca was related to the shell growth. A similar variation was also found when using a direct LIBS analysis on the shell surface, and it might be more practicable to track shell growth by investigating Sr/Ca ratio with Sr ionic line at 421.6 nm. The obtained results prove that calcium （Ca） is qualified as an internal reference for shell analysis, and LIBS is a potential analytical method for seashell study.
文摘Cultivated for its richness in nutrients, tomato culture is demanding fertilizer, especially in calcium. Calcium deficiencies and physiological disorders cause serious diseases in tomatoes. Blossom end rot (BER), in susceptible cultivars, may cause severe economic losses. The goal of this study is to determine the effect of three organic calcium sources on the growth and quality of fruit production of tomatoes. Egg, snail and sea shell powders and extracts have been used as biological fertilizers. The experiment was conducted in a block factorial trial with three replications. The trials comprised two factors: calcium sources and calcium source form (powder and extract). The results showed that the growth parameters and yield were improved by the calcium source, whatever the form. Also, BER was lower in plants treated with calcium contrary to the control. However, plants treated with eggshells showed the best growth (mean) and the lowest rate (0.40%) of BER than the snail and sea shell.
文摘Cultivated for its richness in nutrients, tomato culture is demanding fertilizer, especially in calcium. Calcium deficiencies and physiological disorders cause serious diseases in tomatoes. Blossom end rot (BER), in susceptible cultivars, may cause severe economic losses. The goal of this study is to determine the effect of three organic calcium sources on the growth and quality of fruit production of tomatoes. Egg, snail and sea shell powders and extracts have been used as biological fertilizers. The experiment was conducted in a block factorial trial with three replications. The trials comprised two factors: calcium sources and calcium source form (powder and extract). The results showed that the growth parameters and yield were improved by the calcium source, whatever the form. Also, BER was lower in plants treated with calcium contrary to the control. However, plants treated with eggshells showed the best growth (mean) and the lowest rate (0.40%) of BER than the snail and sea shell.
文摘A vast majority of mollusks grow a hard shell for protection. The structure of these shells comprises several levels of hierarchy that increase their strength and their resistance to natural threats. This article focuses on nacreous shells, which are composed of two distinct layers. The outer layer is made of calcite, which is a hard but brittle material, and the inner layer is made of nacre, a tough and ductile material. The inner and outer layers are therefore made of materials with distinct structures and properties. In this article, we demonstrate that this system is optimum to defeat attacks from predators. A two-scale mod- eling and optimization approach was used. At the macroscale, a two-layer finite element model of a seashell was developed to capture shell geometry. At the microscale, a representative volume element of the microstructure of nacre was used to model the elastic modulus of nacre as well as a multiaxial failure criterion, both expressed as function of microstructural parameters. Experiments were also performed on actual shells of red abalone to validate the results obtained from simulations and gain insight into the way the shell fails under sharp perforation. Both optimization and experimental results revealed that the shell displays optimum performance when two modes of failure coincide within the structure. Finally, guidelines for designing two-layer shells were proposed to improve the performance of engineered protective systems undergoing similar structural and loading conditions.
文摘This short essay focuses on just one of the mythological paintings of Evelyn Pickering De Morgan,Ariadne at Naxos of 1877 at The De Morgan Foundation(Figure 1).1 It consists of an iconographical and iconological analysis of the ancient legend of Ariadne and Theseus,demonstrating Evelyn’s classical erudition and artistic mastery in visualizing a moment in the narrative,the desertion of Ariadne by Theseus on the beach at Naxos.
文摘Marine CaCO3 skeletons have tailored architectures created by nature, which give them structural support and other functions. For example, seashells have dense lamellar structures, while coral, cuttlebone and sea urchin spines have interconnected porous structures. In our experiments, seashells, coral and cuttlebone were hydrothermaily converted to hydroxyapatite （HAP）, and sea urchin spines were converted to Mg-substituted tricalcium phosphate, while maintaining their original structures. Partially converted shell samples have mechanical strength, which is close to that of compact human bone. After implantation of converted shell and spine samples in rat femoral defects for 6 weeks, there was newly formed bone growth up to and around the implants. Some new bone was found to migrate through the pores of converted spine samples and grow inward. These results show good bioactivity and osteoconductivity of the implants, indicating the converted shell and spine samples can be used as bone defect fillers. The interconnected porous HAP scaffolds from converted coral or cuttlebone that have pore size larger than 100μm likely support infiltration of bone cells and vessels, and finally encourage new bone ingrowth.
