The Pacific oyster,Crassostrea gigas,naturally distributing along the coast of northwest Pacific,is one of the most important bivalve species due to its high economic value and fecundity.In China,we have initiated a s...The Pacific oyster,Crassostrea gigas,naturally distributing along the coast of northwest Pacific,is one of the most important bivalve species due to its high economic value and fecundity.In China,we have initiated a selective breeding program on both shell color and growth rate of C.gigas since 2010.A black shell line was obtained through four-generation family selection.In this study,mass selection for growth improvement was conducted in the sixth generation and seventh generation of black shell lines.To assess the progress of potential genetic improvement,the progeny of two generations of black shell lines were selected to evaluate their shell heights via a 450-day farming experiment.As the results,after growing for 450 days,the sixth generation and seventh generation of selected lines were 9.03% and 11.42% larger than the control lines,respectively.During the grow-out stage,the genetic gain of two generations was 8.82%±0.18% and 11.54%±0.43%,respectively;and the corresponding realized heritability was 0.45±0.04 and 0.41±0.04,respectively.These results indicated that the mass selection for shell height achieved steady progress in the two generations of C.gigas.展开更多
Plantain contributes significantly to income generation and food security for millions of people in the world. However, it faces problems of seedlings quantity, quality and availability. The innovation of the “plants...Plantain contributes significantly to income generation and food security for millions of people in the world. However, it faces problems of seedlings quantity, quality and availability. The innovation of the “plants issus de fragments de tiges” (PIF) technique could be a solution to these problems for small holders’ farmers. The aim of this research is to evaluate the effect of clam shells through amendment of Batard and Big Ebanga PIF substrate, on the growth promotion of seedlings and their protection against black Sigatoka disease (BSD). Plantain PIF seedlings of the two varieties were grown in a substrate amended with 1% concentration of the clam shells powder in the presence of negative control in the sterile and non-sterile conditions. Agromorphological characteristics, susceptibility level to BSD, total proteins and polyphenols content were assessed. Because of the presence of clam shells in the substrates, explants germinated quickly, generated high number of shoots, grew taller by 32%, with a diameter of pseudo stems of 30%, and area of leaves of 18% compared to control. In addition, the seedlings were less susceptible to BSD by 73% compared to those of controls. The treatment seems to allow the accumulation of larger amounts of total proteins and polyphenols before inoculation and after inoculation that could participate in the growth promotion and the reduction of plant’s susceptibility level. Clam shells treatment acts as a biofertilizer/biopesticide and could be helpful to boost production of plantain seedlings, the use of the by-products of fishing in agriculture and helps alleviate poverty of small holders’ farmers.展开更多
Existence of gravitation inverse matter in finite space is shown inevitable. As an example, direction of gravitation of rest mass of electron is opposite to that of positron. That is, electron and positron are gravita...Existence of gravitation inverse matter in finite space is shown inevitable. As an example, direction of gravitation of rest mass of electron is opposite to that of positron. That is, electron and positron are gravitationally repulsive to each other. The physical space has previously been shown of finite extent. Therefore, if gravitation normal matter is found prevailing in the physical space then, according to the law of mass/charge balance in finite space, the Universe, i.e., the physical space and all that it contains/confines, must be a shell-structured black hole in a higher dimensional space.展开更多
Lithium–sulfur batteries are promising next-generation energy storage devices beyond conventional lithium ion batteries. However, it suffers from rapid capacity fading and poor cyclic stability. Here we report a faci...Lithium–sulfur batteries are promising next-generation energy storage devices beyond conventional lithium ion batteries. However, it suffers from rapid capacity fading and poor cyclic stability. Here we report a facile in situ sulfur deposition and chemical oxidative polymerization method for preparing acetylene black/sulfur@polypyrrole（AB/S@PPy） composite as a cathode material for lithium–sulfur batteries. It is demonstrated that PPy is covered uniformly onto the surface of the AB/S composite forming a core–shell structure. In the structure, AB in the matrix and PPy on the surface acts as a combined conductive framework to provide ions and electrons transport pathways, and to inhibit the dissolution or diffusion of polysulfide into the electrolyte. The as-designed AB/S@PPy composite exhibits excellent rate capability and cyclic stability. The initial discharge specific capacity is as high as 1179.4 m Ah/g, and remains at769.3 m Ah/g after 80 cycles at 0.2 C. Even at a high rate（0.5 C）, a maximum discharge capacity of 811.1 m Ah/g is still achieved for the AB/S@PPy composite after activation, and the capacity retention is over62.5% after 200 cycles.展开更多
Nanoscale ionic materials（NIMS） based on carbon black（CB） were prepared through a facile method. Firstly, CB was oxidized in the mixture of nitric acid and sulfuric acid, resulting in a large amounts of -COOH on s...Nanoscale ionic materials（NIMS） based on carbon black（CB） were prepared through a facile method. Firstly, CB was oxidized in the mixture of nitric acid and sulfuric acid, resulting in a large amounts of -COOH on surface of CB. Then oxidized CB was grafted by polyetheramine through neutralization reaction between -COOH of CB and -NH_2- of polyetheramine, and CB derivatives were obtained. This surface- functionalized CB can behave as liquid at ambient temperature in the absence of solvent by carefully varying the components. FTIR and thermaogravimelric analysis confirmed that the successively grafting of polyetheramine. TEM revealed the monodisperse core-shell structure of CB derivatives particles. The viscoelasticity of CB derivatives were closely related to the molecular weight and loading of polyetheramine. The unique core- shell and ionic structure and flowability of these CB derivatives could guide our future work on obtaining NIMs with tunable and controllable properties and broaden its commercial applications.展开更多
We consider the Hyperverse as a collection of multiverses in 5-dimensional spacetime with gravitational constant G. Each multiverse in our simplified model is a bouquet of nested spherical Gogberashvili shells. If g&l...We consider the Hyperverse as a collection of multiverses in 5-dimensional spacetime with gravitational constant G. Each multiverse in our simplified model is a bouquet of nested spherical Gogberashvili shells. If g<sub>k</sub> is the gravitational constant of a thin shell S<sub>k</sub> and ε<sub>k</sub>, its thickness then G ~ ε<sub>k</sub>g<sub>k</sub>. The physical universe is supposed to be one of those shells inside the local nested bouquet called Local Multiverse. We relate this construction to Robinson-Trautman metrics describing expanding spacetimes with spherical gravitational waves. Supermassive astronomical black holes, located at cores of elliptic/spiral galaxies, are also conjecturally described within this theory. Our constructions are equally consistent with the modern theory of cosmological coupling.展开更多
通过自组装方式采用一步法制备了锂离子电池硅碳复合电极材料.使用X射线衍射仪(XRD)、透射电子显微镜(TEM)和扫描电子显微镜(SEM)等对样品结构进行表征.结果表明,聚乙烯吡咯烷酮(PVP)包覆的纳米硅颗粒(Si@PVP)均匀嵌入到具有三维网络纳...通过自组装方式采用一步法制备了锂离子电池硅碳复合电极材料.使用X射线衍射仪(XRD)、透射电子显微镜(TEM)和扫描电子显微镜(SEM)等对样品结构进行表征.结果表明,聚乙烯吡咯烷酮(PVP)包覆的纳米硅颗粒(Si@PVP)均匀嵌入到具有三维网络纳米孔结构的导电石墨化炭黑(GCB)骨架中,形成核壳复合型(Si@PVP-GCB)纳米颗粒,既提高了该复合电极材料的导电性能,又改善了材料的机械强度.在纳米级GCB颗粒内部存在的中空石墨环结构和包覆在纳米Si颗粒外面的PVP包覆层都有效缓冲了纳米Si颗粒在充放电过程中较大的体积变化,从而使纳米Si颗粒更加稳定.电化学测试结果表明,Si@PVP-GCB电极材料在电流密度为50 m A/g时,经过100次循环后其可逆容量仍达到545 m A·h/g时,远高于商品化的石墨微球(GMs)电极材料的容量(理论容量为372 m A·h/g).展开更多
基金supported by the grants from the National Natural Science Foundation of China (Nos. 3177 2843, 31741122)the Earmarked Fund for Agriculture Seed Improvement Project of Shandong Province (No. 2017LZGC009)the Fundamental Research Funds for the Central Universities (No. 201762014)
文摘The Pacific oyster,Crassostrea gigas,naturally distributing along the coast of northwest Pacific,is one of the most important bivalve species due to its high economic value and fecundity.In China,we have initiated a selective breeding program on both shell color and growth rate of C.gigas since 2010.A black shell line was obtained through four-generation family selection.In this study,mass selection for growth improvement was conducted in the sixth generation and seventh generation of black shell lines.To assess the progress of potential genetic improvement,the progeny of two generations of black shell lines were selected to evaluate their shell heights via a 450-day farming experiment.As the results,after growing for 450 days,the sixth generation and seventh generation of selected lines were 9.03% and 11.42% larger than the control lines,respectively.During the grow-out stage,the genetic gain of two generations was 8.82%±0.18% and 11.54%±0.43%,respectively;and the corresponding realized heritability was 0.45±0.04 and 0.41±0.04,respectively.These results indicated that the mass selection for shell height achieved steady progress in the two generations of C.gigas.
文摘Plantain contributes significantly to income generation and food security for millions of people in the world. However, it faces problems of seedlings quantity, quality and availability. The innovation of the “plants issus de fragments de tiges” (PIF) technique could be a solution to these problems for small holders’ farmers. The aim of this research is to evaluate the effect of clam shells through amendment of Batard and Big Ebanga PIF substrate, on the growth promotion of seedlings and their protection against black Sigatoka disease (BSD). Plantain PIF seedlings of the two varieties were grown in a substrate amended with 1% concentration of the clam shells powder in the presence of negative control in the sterile and non-sterile conditions. Agromorphological characteristics, susceptibility level to BSD, total proteins and polyphenols content were assessed. Because of the presence of clam shells in the substrates, explants germinated quickly, generated high number of shoots, grew taller by 32%, with a diameter of pseudo stems of 30%, and area of leaves of 18% compared to control. In addition, the seedlings were less susceptible to BSD by 73% compared to those of controls. The treatment seems to allow the accumulation of larger amounts of total proteins and polyphenols before inoculation and after inoculation that could participate in the growth promotion and the reduction of plant’s susceptibility level. Clam shells treatment acts as a biofertilizer/biopesticide and could be helpful to boost production of plantain seedlings, the use of the by-products of fishing in agriculture and helps alleviate poverty of small holders’ farmers.
文摘Existence of gravitation inverse matter in finite space is shown inevitable. As an example, direction of gravitation of rest mass of electron is opposite to that of positron. That is, electron and positron are gravitationally repulsive to each other. The physical space has previously been shown of finite extent. Therefore, if gravitation normal matter is found prevailing in the physical space then, according to the law of mass/charge balance in finite space, the Universe, i.e., the physical space and all that it contains/confines, must be a shell-structured black hole in a higher dimensional space.
基金the financial support from the National Natural Science Foundation of China (No. 51674221)
文摘Lithium–sulfur batteries are promising next-generation energy storage devices beyond conventional lithium ion batteries. However, it suffers from rapid capacity fading and poor cyclic stability. Here we report a facile in situ sulfur deposition and chemical oxidative polymerization method for preparing acetylene black/sulfur@polypyrrole（AB/S@PPy） composite as a cathode material for lithium–sulfur batteries. It is demonstrated that PPy is covered uniformly onto the surface of the AB/S composite forming a core–shell structure. In the structure, AB in the matrix and PPy on the surface acts as a combined conductive framework to provide ions and electrons transport pathways, and to inhibit the dissolution or diffusion of polysulfide into the electrolyte. The as-designed AB/S@PPy composite exhibits excellent rate capability and cyclic stability. The initial discharge specific capacity is as high as 1179.4 m Ah/g, and remains at769.3 m Ah/g after 80 cycles at 0.2 C. Even at a high rate（0.5 C）, a maximum discharge capacity of 811.1 m Ah/g is still achieved for the AB/S@PPy composite after activation, and the capacity retention is over62.5% after 200 cycles.
基金Funded by the National Natural Science Foundation of China(No.51003084)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry
文摘Nanoscale ionic materials（NIMS） based on carbon black（CB） were prepared through a facile method. Firstly, CB was oxidized in the mixture of nitric acid and sulfuric acid, resulting in a large amounts of -COOH on surface of CB. Then oxidized CB was grafted by polyetheramine through neutralization reaction between -COOH of CB and -NH_2- of polyetheramine, and CB derivatives were obtained. This surface- functionalized CB can behave as liquid at ambient temperature in the absence of solvent by carefully varying the components. FTIR and thermaogravimelric analysis confirmed that the successively grafting of polyetheramine. TEM revealed the monodisperse core-shell structure of CB derivatives particles. The viscoelasticity of CB derivatives were closely related to the molecular weight and loading of polyetheramine. The unique core- shell and ionic structure and flowability of these CB derivatives could guide our future work on obtaining NIMs with tunable and controllable properties and broaden its commercial applications.
文摘We consider the Hyperverse as a collection of multiverses in 5-dimensional spacetime with gravitational constant G. Each multiverse in our simplified model is a bouquet of nested spherical Gogberashvili shells. If g<sub>k</sub> is the gravitational constant of a thin shell S<sub>k</sub> and ε<sub>k</sub>, its thickness then G ~ ε<sub>k</sub>g<sub>k</sub>. The physical universe is supposed to be one of those shells inside the local nested bouquet called Local Multiverse. We relate this construction to Robinson-Trautman metrics describing expanding spacetimes with spherical gravitational waves. Supermassive astronomical black holes, located at cores of elliptic/spiral galaxies, are also conjecturally described within this theory. Our constructions are equally consistent with the modern theory of cosmological coupling.
文摘通过自组装方式采用一步法制备了锂离子电池硅碳复合电极材料.使用X射线衍射仪(XRD)、透射电子显微镜(TEM)和扫描电子显微镜(SEM)等对样品结构进行表征.结果表明,聚乙烯吡咯烷酮(PVP)包覆的纳米硅颗粒(Si@PVP)均匀嵌入到具有三维网络纳米孔结构的导电石墨化炭黑(GCB)骨架中,形成核壳复合型(Si@PVP-GCB)纳米颗粒,既提高了该复合电极材料的导电性能,又改善了材料的机械强度.在纳米级GCB颗粒内部存在的中空石墨环结构和包覆在纳米Si颗粒外面的PVP包覆层都有效缓冲了纳米Si颗粒在充放电过程中较大的体积变化,从而使纳米Si颗粒更加稳定.电化学测试结果表明,Si@PVP-GCB电极材料在电流密度为50 m A/g时,经过100次循环后其可逆容量仍达到545 m A·h/g时,远高于商品化的石墨微球(GMs)电极材料的容量(理论容量为372 m A·h/g).
