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Live-streaming selling strategies for competitive firms
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作者 Quan Du Zhixin Chen +1 位作者 Jie Wu Xiang Ji 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第5期22-35,I0006,I0007,共16页
The booming live-streaming commerce has significantly changed the traditional e-commerce model,thus attracting much attention from both industry and academia.In recent years,an increasing number of scholars have appli... The booming live-streaming commerce has significantly changed the traditional e-commerce model,thus attracting much attention from both industry and academia.In recent years,an increasing number of scholars have applied analytical models to explore live-streaming strategies for firms in different scenarios.However,the previous literature mainly considers monopolists,while in the real world,competition is not rare.To fill this gap between the literature and practical observations,this paper applies a game theoretical model to study live-streaming adoption and pricing strategy for firms under competitive environments.The results show that,for competitive firms,the equilibrium strategy depends on the relation between the commission rate and the intensity of the market expansion effect.Additionally,compared to the case in which no firm adopts live-streaming,competitive firms do not always benefit from the adoption of live-streaming selling.The paper also shows that competition plays a negative role in inducing a firm to adopt live-streaming. 展开更多
关键词 live-streaming commerce live-streaming strategy game COMPETITION
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Driving inward growth of lithium metal in hollow microcapsule hosts by heteroatom‐controlled nucleation
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作者 Siwon Kim Hong Rim Shin +2 位作者 Ki Jae Kim Min‐Sik Park Jong‐Won Lee 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期262-272,共11页
The application of Li metal anodes in rechargeable batteries is impeded by safety issues arising from the severe volume changes and formation of dendritic Li deposits.Three‐dimensional hollow carbon is receiving incr... The application of Li metal anodes in rechargeable batteries is impeded by safety issues arising from the severe volume changes and formation of dendritic Li deposits.Three‐dimensional hollow carbon is receiving increasing attention as a host material capable of accommodating Li metal inside its cavity;however,uncontrollable and nonuniform deposition of Li remains a challenge.In this study,we synthesize metal–organic framework‐derived carbon microcapsules with heteroatom clusters(Zn and Ag)on the capsule walls and it is demonstrated that Ag‐assisted nucleation of Li metal alters the outward‐to‐inward growth in the microcapsule host.Zn‐incorporated microcapsules are prepared via chemical etching of zeolitic imidazole framework‐8 polyhedra and are subsequently decorated with Ag by a galvanic displacement reaction between Ag^(+) and metallic Zn.Galvanically introduced Ag significantly reduces the energy barrier and increases the reaction rate for Li nucleation in the microcapsule host upon Li plating.Through combined electrochemical,microstructural,and computational studies,we verify the beneficial role of Ag‐assisted Li nucleation in facilitating inward growth inside the cavity of the microcapsule host and,in turn,enhancing electrochemical performance.This study provides new insights into the design of reversible host materials for practical Li metal batteries. 展开更多
关键词 hollow carbon hosts lithium metal batteries lithium plating metal-organic frameworks NUCLEATION
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Hatching and development of maize cyst nematode Heterodera zeae infecting different plant hosts
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作者 Jiangkuan Cui Haohao Ren +5 位作者 BoWang Fujie Chang Xuehai Zhang Haoguang Meng Shijun Jiang Jihua Tang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1593-1603,共11页
The occurrence, distribution, and rapid molecular detection technology of Heterodera zeae Koshy et al. 1971, have been reported in China. We explored the biological characteristics of H. zeae sampled in Henan Province... The occurrence, distribution, and rapid molecular detection technology of Heterodera zeae Koshy et al. 1971, have been reported in China. We explored the biological characteristics of H. zeae sampled in Henan Province, China to understand its interaction with plants. Cysts and second-stage juveniles(J2s) were identified under an optical and scanning electron microscope, internal transcribed spacer(ITS) phylogenetic tree, and sequence characterized amplified region(SCAR)-PCR analyses. The optimum hatching temperatures of H. zeae were 30°C and 28°C, with cumulative hatching rates of 16.5 and 16.1%, respectively, at 30 days post-hatching(dph). The hatching rate of H. zeae eggs was improved by 20-and 50-time maize soil leachate and root juice, and 10-time root exudates. The hatching rate in 10-time root exudates was the highest(25.9%). The 10-time root exudates of maize and millet produced the highest hatching rate at 30 dph(25.9 and 22.9%, respectively), followed by wheat(19.9%), barley(18.3%), and rice(17.6%). Heterodera zeae developed faster in maize than in other crops. Fourth-stage juveniles(J4s) were detected in maize roots 8 days post-inoculation(dpi) at 28°C but not in other crops. Combined with hatching tests, the Huang–Huai–Hai summer maize region and the south and central-southwest mountainous maize areas are highly suitable for H. zeae in China. This is the first systematically study of the hatching and infection characteristics on different plant hosts of corn cyst nematode H. zeae in temperate regions. This study laid a theoretical foundation for the rapid spread and high environmental adaptability of corn cyst nematode. 展开更多
关键词 crop host resistance Heterodera zeae incubation fluid maize cyst nematode nematode development nematodehatching
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Research on the Impact of Social Media Live-Streaming on Consumer Purchasing Behavior and Its Coping Strategies
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作者 Xuehui Ding Rosidah Musa 《Proceedings of Business and Economic Studies》 2024年第3期188-193,共6页
Due to the rapid development of network technology and the popularity of live-streaming,more and more businesses and individuals are using live-streaming to promote their products,giving rise to a new marketing model ... Due to the rapid development of network technology and the popularity of live-streaming,more and more businesses and individuals are using live-streaming to promote their products,giving rise to a new marketing model of social media live-streaming.Based on the social media live-streaming market,businesses or enterprises focus on tapping into new consumer demand,and social media live-streaming marketing has gradually expanded into various fields.Based on the SOR theory,this paper discusses how to improve the coping strategies of consumer purchasing behavior through social media live-streaming by analyzing the representative factors affecting consumer purchasing behavior such as anchors,brands,and live-streaming content in social media live-streaming.The results of this study will contribute to a better understanding of the relationship between social media live-streaming marketing models and consumer purchasing behavior and will help to reveal the potentials and limitations of social media live-streaming,thus providing valuable ideas and scientific basis for social media live-streaming marketing strategies. 展开更多
关键词 SOR theory ANCHOR BRAND live-streaming content Coping strategy
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Study on Developmental Durations and Fecundity of Phenacoccus solenopsis Tinsley on Four Species of Hosts 被引量:8
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作者 关鑫 陆永跃 曾玲 《Agricultural Science & Technology》 CAS 2012年第2期408-411,共4页
[Objective] The aim was to study on the effect of hosts on development and reproduction of mealybug (Phenacoccus solenopsis Tinsley). [Method] Observation was conducted on developmental durations and fecundity of Ph... [Objective] The aim was to study on the effect of hosts on development and reproduction of mealybug (Phenacoccus solenopsis Tinsley). [Method] Observation was conducted on developmental durations and fecundity of Phenacoccus solenopsis Tinsley fed on Gossypium spp., Nicotiana tabacum, Solanum tuberosum L and Hibiscus rosa-sinensis. [Result] There were differences among all durations, generation durations and fecundities of the mealybug adult females. Specifically, the generation durations on cotton (Gossypium spp.), tobacco( Nicotiana tabacum), potato (Solanum tuberosum L) and Hibiscus rosa-sinensis were 30.2, 28.2, 37.3, and 27.7 d, and the fecundities per female were 626.0, 417.2, 552.5, and 183.2 ind., respectively. [Conclusion] The mealybug would have strong pontential in population growth when fed on cotton, tobacco and potato. 展开更多
关键词 Phenacoccus solenopsis Tinsley host plants Development duration FECUNDITY
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Diversity of parasitic cuckoos and their hosts in China 被引量:11
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作者 杨灿朝 梁伟 +5 位作者 Anton ANTONOV 蔡燕 Brd G.STOKKE Frode FOSSφY Arne MOKSNES Eivin RφSKAFT 《Chinese Birds》 2012年第1期9-32,72,共25页
In this exposé we provide the first review of host use by brood parasitic cuckoos in a multiple-cuckoo system in China, based on our own long-term field data and a compilation of observations obtained from the li... In this exposé we provide the first review of host use by brood parasitic cuckoos in a multiple-cuckoo system in China, based on our own long-term field data and a compilation of observations obtained from the literature. In total, we found that 11 species of cuckoos utilized altogether 55 host species. These hosts belong to 15 families, in which Sylviidae, Turdidae and Timaliidae account for 22.6%, 20.8% and 17.0% of parasitism records, respectively. The Common Cuckoo (Cuculus canorus) had the widest range of host species, accounting for 45.5% of the total number of parasitized species (25 in 10 families) of all parasitism records and is the most frequent brood parasite in the country. Cuckoo species differed in their egg coloration and the extent of egg polymorphism with most of them, e.g. the Common Cuckoo, the Lesser Cuckoo (C. poliocephalus) and the Plaintive Cuckoo (Cacomantis merulinus) laying well mimetic eggs with respect to their hosts based on human being’s visual observations, while others such as the Large Hawk-cuckoo (C. sparverioides), the Himalayan Cuckoo (C. saturatus) and the Asian Emerald Cuckoo (Chrysococcyx maculatus) usually laid non-mimetic eggs. The use of cuckoo hosts and egg color variation in China are compared with those in other parts of their ranges in Asia. 展开更多
关键词 brood parasitism egg color host use multiple-cuckoo system egg polymorphism
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Geographic variation in parasitism rates of two sympatric cuckoo hosts in China 被引量:6
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作者 Can-Chao YANG Dong-Lai LI +3 位作者 Long-Wu WANG Guo-Xian LIANG Zheng-Wang ZHANG Wei LIANG 《Zoological Research》 CAS CSCD 北大核心 2014年第1期67-71,共5页
Rates of brood parasitism vary extensively among host species and populations of a single host species. In this study, we documented and compared parasitism rates of two sympatric hosts, the Oriental Reed Warbler (Ac... Rates of brood parasitism vary extensively among host species and populations of a single host species. In this study, we documented and compared parasitism rates of two sympatric hosts, the Oriental Reed Warbler (Acrocephalus orientalis) and the Reed Parrotbill (Paradoxornis heudei), in three populations in China. We found that the Common Cuckoo (Cuculus canorus) is the only parasite using both the Oriental Reed Warbler and Reed Parrotbill as hosts, with a parasitism rate of 22.4%-34.3% and 0%-4.6%, respectively. The multiple parasitism rates were positively correlated with local parasitism rates across three geographic populations of Oriental Reed Warbler, which implies that higher pressure of parasitism lead to higher multiple parasitism rate. Furthermore, only one phenotype of cuckoo eggs was found in the nests of these two host species. Our results lead to two conclusions: (1) The Oriental Reed Warbler should be considered the major host of Common Cuckoo in our study sites; and (2) obligate parasitism on Oriental Reed Warbler by Common Cuckoo is specialized but flexible to some extent, i.e., using Reed Parrotbill as a secondary host. Further studies focusing on egg recognition and rejection behaviour of these two host species should be conducted to test our predictions. 展开更多
关键词 Acrocephalus orientalis Brood parasitism host shift Egg phenotype before host shift Paradoxornis heudei.
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Carbon-based derivatives from metal-organic frameworks as cathode hosts for Li–S batteries 被引量:7
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作者 Qingping Wu Xuejun Zhou +2 位作者 Jun Xu Fahai Cao Chilin Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第11期94-113,共20页
Lithium-sulfur batteries(Li–S batteries) are promising candidates for the next generation high-energy rechargeable Li batteries due to their high theoretical specific capacity(1672 m Ahg-1) and energy density(2500 Wh... Lithium-sulfur batteries(Li–S batteries) are promising candidates for the next generation high-energy rechargeable Li batteries due to their high theoretical specific capacity(1672 m Ahg-1) and energy density(2500 Wh kg-1). The commercialization of Li–S batteries is impeded by several key challenges at cathode side, e.g. the insulating nature of sulfur and discharged products(Li2S 2 and Li2S), the solubility of long-chain polysulfides and volume variation of sulfur cathode upon cycling. Recently, the carbonbased derivatives from metal-organic frameworks(MOFs) has emerged talent in their utilization as cathode hosts for Li–S batteries. They are not only highly conductive and porous to enable the acceleration of Li +/e-transfer and accommodation of volumetric expansion of sulfur cathode during cycling, but also enriched by controllable chemical active sites to enable the adsorption of polysulfides and promotion of their conversion reaction kinetics. In this review, based on the types of MOFs(e.g. ZIF-8, ZIF-67, Prussian blue, Al-MOF, MOF-5, Cu-MOF, Ni-MOF), the synthetic methods, formation process and morphology, structural superiority of MOFs-derived carbon frameworks along with their electrochemical performance as cathode host in Li–S batteries are summarized and discussed. 展开更多
关键词 Lithium-sulfur BATTERIES Carbon-based DERIVATIVES Metal-organic frame works CATHODE host
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Finger Printing and Quantitative Analysis of <i>Cuscuta chinensis</i>Flavonoid Contents from Different Hosts by RP-HPLC 被引量:4
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作者 Maryam Shekarchi Babak Mokhtari Kondori +4 位作者 Homa Hajimehdipoor Leila Abdi Mohsen Naseri Mojgan Pourfarzib Gholamreza Amin 《Food and Nutrition Sciences》 2014年第10期914-921,共8页
Background: Cuscuta spp. known as dodders, have been used as traditional medicines in eastern and southern Asian countries for many disorders such as gastrointestinal, respiratory, endocrine, skin and neurological dis... Background: Cuscuta spp. known as dodders, have been used as traditional medicines in eastern and southern Asian countries for many disorders such as gastrointestinal, respiratory, endocrine, skin and neurological diseases (Drug of mania). Flavonoids are the main biologically active constituents in Cuscuta genus especially in C. chinensis. Our aim in this study was to identify and discriminate between C. chinensis samples which were collected from different hosts, by using the pattern recognition aided fingerprint analysis and comparison of the content of four major flavonoids (hyperoside, rutin, isorhamnetin, kaempferol). Material and methods: Samples were collected from nine different plants in the same time and place, dried, grinded and extracted with methanol (80%) by repeated maceration. Extractions were evaluated by high performance liquid chromatography analysis and fingerprinting. Results: Beside chromatographic fingerprint using similarity index, we compared the content of 4 major flavonoids (hyperoside, rutin, isorhamnetin, kaempferol) of C. chinensis samples on different hosts. Coclusion: The results showed that there were significant differences between the content of four major flavonoids of nine C. chinensis samples, but chromatographic fingerprint by similarity index of more than 0.88, showed that the sample consistency was similar. So, it was suggested that combination of chromatographic fingerprint and the content determination of major flavonoids could be used to evaluate the quality control of C. chinensis from different hosts. 展开更多
关键词 CUSCUTA CHINENSIS Fingerprint FLAVONOIDS hosts Similarity
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Identification of three Berberis species as potential alternate hosts for Puccinia striiformis f. sp. tritici in wheat-growing regions of Xinjiang, China 被引量:2
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作者 ZHUANG Hua ZHAO Jing +2 位作者 HUANG Li-li KANG Zhen-sheng ZHAO Jie 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第12期2786-2792,共7页
Since the recent discovery of barberry(Berberis spp.)as an alternate host for the stripe rust pathogen Puccinia striiformis,many Chinese Berberis species have been identified as alternate hosts for P.striiformis f.sp.... Since the recent discovery of barberry(Berberis spp.)as an alternate host for the stripe rust pathogen Puccinia striiformis,many Chinese Berberis species have been identified as alternate hosts for P.striiformis f.sp.tritici.However,little is known about Berberis species and their distribution in wheat-growing regions in Xinjiang,China,where stripe rust is endemic.As the largest province or autonomous region,Xinjiang represents a relatively independent epidemic region for wheat stripe rust in China.In this study,we con ducted a survey of barberry plants in the main wheat-growi ng areas of Xinjiang.We iden tified three Berberis species,B.heteropoda,B.nummularia and B.kaschgarica,and con firmed their roles as potential alternate hosts for P.striiformis f.sp.tritici in the laboratory. 展开更多
关键词 barberry ALTERNATE host sexual REPRODUCTION STRIPE RUST yellow RUST
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3D MXene architectures as sulfur hosts for high-performance lithium-sulfur batteries 被引量:11
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作者 Yu-Hong Liu Cao-Yu Wang +2 位作者 Si-Lin Yang Fei-Fei Cao Huan Ye 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第3期429-439,I0012,共12页
Lithium-sulfur batteries(LSBs)are one of the most promising energy storage devices because of their high theoretical energy density;however,inherent issues including poor electrical conductivity and severe dissolution... Lithium-sulfur batteries(LSBs)are one of the most promising energy storage devices because of their high theoretical energy density;however,inherent issues including poor electrical conductivity and severe dissolution of S and its discharged products hinder their practical applications.MXenes have metallic conductivity,ultra-thin two-dimensional(2D)structures,rich surface functional groups,and macrostructural adjustability and have been widely used to design advanced sulfur hosts.3D network structures assembled by 2D MXene nanosheets have shown superior performance for improving reaction kinetics,accommodating and dispersing sulfur at the micro-/nanoscale,and capturing polysulfides due to their porous interconnected structure.Herein,the applications of MXene architectures related to 2D layered structures,3D multilayered structures,and 3D spherical structures as sulfur hosts are reviewed.The structure-performance relationship,challenges for current designs,and opportunities for future 3D architectures for LSBs are also analyzed. 展开更多
关键词 Lithium-sulfur batteries Cathodes Sulfur hosts MXenes 3D architectures
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Multifunctional roles of carbon-based hosts for Li-metal anodes:A review 被引量:14
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作者 Xiaolin Yan Liang Lin +4 位作者 Qiulin Chen Qingshui Xie Baihua Qu Laisen Wang Dong-Liang Peng 《Carbon Energy》 CAS 2021年第2期303-329,共27页
With its high theoretical capacity,lithium(Li)metal is recognized as the most potential anode for realizing a high-performance energy storage system.A series of questions(severe safety hazard,low Coulombic efficiency,... With its high theoretical capacity,lithium(Li)metal is recognized as the most potential anode for realizing a high-performance energy storage system.A series of questions(severe safety hazard,low Coulombic efficiency,short lifetime,etc.)induced by uncontrollable dendrites growth,unstable solid electrolyte interface layer,and large volume change,make practical application of Li-metal anodes still a threshold.Due to their highly appealing properties,carbon-based materials as hosts to composite with Li metal have been passionately investigated for improving the performance of Li-metal batteries.This review displays an overview of the critical role of carbon-based hosts for improving the comprehensive performance of Li-metal anodes.Based on correlated mainstream models,the main failure mechanism of Li-metal anodes is introduced.The advantages and strategies of carbon-based hosts to address the corresponding challenges are generalized.The unique function,existing limitation,and recent research progress of key carbon-based host materials for Li-metal anodes are reviewed.Finally,a conclusion and an outlook for future research of carbon-based hosts are presented.This review is dedicated to summarizing the advances of carbon-based materials hosts in recent years and providing a reference for the further development of carbonbased hosts for advanced Li-metal anodes. 展开更多
关键词 carbon-based hosts dendrites growth electrochemical performance Li-metal anodes volume expansion
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Mesoporous Graphene Hosts for Dendrite-Free Lithium Metal Anode in Working Rechargeable Batteries 被引量:11
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作者 He Liu Xinbing Cheng +6 位作者 Rui Zhang Peng Shi Xin Shen Xiaoru Chen Tao Li Jiaqi Huang Qiang Zhang 《Transactions of Tianjin University》 EI CAS 2020年第2期127-134,共8页
Lithium(Li) metal anode has received extensive attentions due to its ultrahigh theoretical capacity and the most negative electrode potential. However, dendrite growth severely impedes the practical applications of th... Lithium(Li) metal anode has received extensive attentions due to its ultrahigh theoretical capacity and the most negative electrode potential. However, dendrite growth severely impedes the practical applications of the Li metal anode in rechargeable batteries. In this contribution, a mesoporous graphene with a high specific surface area was synthesized to host the Li metal anode. The mesoporous graphene host(MGH) has a high specific surface area(2090 m^2/g), which affords free space and an interconnected conductive pathway for Li plating and stripping, thus alleviating the volume variation and reducing the generation of dead Li during repeated cycles. More importantly, the high specific surface area of MGH efficiently reduces the local current density of the electrode, which favors a uniform Li nucleation and plating behavior, rendering a dendritefree deposition morphology at a low overpotential. These factors synergistically boost the Li utilization(90.1% vs. 70.1% for Cu foil) and life span(150 cycles vs. 100 cycles for Cu foil) with a low polarization of MGH electrode at an ultrahigh current of 15.0 mA/cm^2. The as-prepared MGH can provide fresh insights into the electrode design of the Li metal anode operating at high rates. 展开更多
关键词 LITHIUM metal anode MESOPOROUS GRAPHENE hosts Dendrite-free plating behavior Working RECHARGEABLE batteries Composite electrode
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Population Diversity of Puccinia graminis is Sustained Through Sexual Cycle on Alternate Hosts 被引量:2
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作者 Yue Jin Matt Rouse Jim Groth 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第2期262-264,共3页
A high degree of virulence diversity has been maintained in the population of Puccinia graminis f. sp. tritici (Pgt) in northwestern United States. Although Berberis vulgaris is present in the region and Pgt has bee... A high degree of virulence diversity has been maintained in the population of Puccinia graminis f. sp. tritici (Pgt) in northwestern United States. Although Berberis vulgaris is present in the region and Pgt has been isolated from aecial infections on B. vulgaris, the population is too diverse to be explained by the limited presence of B. vulgaris alone. Since 2008, we have isolated P. graminis from aecial infections on fruits of Mahonia repens and Mahonia aquifolium from northwestern United States. These two native woody shrub species, widely distributed in western North America, were once classified as resistant to P. graminis based on artificial inoculations. By isolating P. graminis from aecia, we established that M. repens and M. aquifolium along with B. vulgaris (albeit infrequent) serve as the alternate hosts ofP. graminis in the region. The isolates of P. graminis from Mahonia of North America had diverse virulence patterns and most of the isolates could be differentiated on Morocco, Line E, Chinese Spring, Little Club, LMPG-6, Rusty, and other genotypes that are considered to be universally susceptible to most Pgt isolates. This discovery explained the persistence of virulence diversity of Pgt observed in isolates derived from uredinia on cereal crops in the region. In addition to cereal crops, uredinial stage of the P. graminis population is sustained by wild grasses, especially Elymus glaucus, a native grass sharing the same habitat with the rusted Mahonia spp. Although virulence to some important stem rust resistance genes was observed in some isolates derived from Mahonia of North America when tested against single stem rust resistance gene stocks, the overall virulence is very limited in these isolates. This is likely a result of limited selection pressure on the rust population. In contrast to northwestern United Sates, the Pgt population in east of the Rocky Mountains of North America has declined steadily with a single race, QFCSC, being predominant in the last decade. This decline is likely due to a combination of factors, of which a lack of sexual recombination in the region is perhaps the most important one. 展开更多
关键词 Puccinia graminis f. sp. tritici wheat stem rust alternate host Mahonia aquifolium M. repens Berberis vulgaris
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High-Entropy Spinel Oxide Nanofibers as Catalytic Sulfur Hosts Promise the High Gravimetric and Volumetric Capacities for Lithium–Sulfur Batteries 被引量:6
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作者 Liyuan Tian Ze Zhang +2 位作者 Sheng Liu Guoran Li Xueping Gao 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2022年第2期645-654,共10页
The exploration of new catalytic hosts is highly important to tackle the sluggish electrochemical kinetics of sulfur redox for achieving high energy density of lithium–sulfur batteries.Herein,for the first time,we pr... The exploration of new catalytic hosts is highly important to tackle the sluggish electrochemical kinetics of sulfur redox for achieving high energy density of lithium–sulfur batteries.Herein,for the first time,we present high-entropy oxide(HEO,(Mg_(0.2)Mn_(0.2)Ni_(0.2)Co_(0.2)Zn_(0.2))Fe_(2)O_(4))nanofibers as catalytic host of sulfur.The HEO nanofibers show a synergistic effect among multiple metal cations in spinel structure that enables strong chemical confinement of soluble polysulfides and fast kinetics for polysulfide conversion.Consequently,the S/HEO composite displays the high gravimetric capacity of 1368.7 mAh g^(−1) at 0.1 C rate,excellent rate capability with the discharge capacity of 632.1 mAh g^(−1) at 5 C rate,and desirable cycle stability.Furthermore,the S/HEO composite shows desirable sulfur utilization and good cycle stability under a harsh operating condition of high sulfur loading(4.6 mg cm^(−2))or low electrolyte/sulfur ratio(5μL mg^(−1)).More impressively,the high volumetric capacity of 2627.9 mAh cm^(−3) is achieved simultaneously for the S/HEO composite due to the high tap density of 1.92 g cm^(−3),nearly 2.5 times of the conventional sulfur/carbon composite.Therefore,based on high-entropy oxide materials,this work affords a fresh concept of elevating the gravimetric/volumetric capacities of sulfur cathodes for lithium–sulfur batteries. 展开更多
关键词 catalytic host high-entropy oxide lithium-sulfur battery polysulfide conversion spinel oxide nanofibers
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Hepatitis B virus lineages in mammalian hosts:Potential for bidirectional cross-species transmission 被引量:1
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作者 Cibele R Bonvicino Miguel A Moreira Marcelo A Soares 《World Journal of Gastroenterology》 SCIE CAS 2014年第24期7665-7674,共10页
The hepatitis B virus(HBV)is a cosmopolitan infectious agent currently affecting over 350 million people worldwide,presently accounting for more than two billion infections.In addition to man,other hepatitis virus str... The hepatitis B virus(HBV)is a cosmopolitan infectious agent currently affecting over 350 million people worldwide,presently accounting for more than two billion infections.In addition to man,other hepatitis virus strains infect species of several mammalian families of the Primates,Rodentia and Chiroptera orders,in addition to birds.The mounting evidence of HBV infection in African,Asian and neotropical primates draws attention to the potential crossspecies,zoonotic transmission of these viruses to man.Moreover,recent evidence also suggests the humans may also function as a source of viral infection to other mammals,particularly to domestic animals like poultry and swine.In this review,we list all evidence of HBV and HBVlike infection of nonhuman mammals and discuss their potential roles as donors or recipients of these viruses to humans and to other closely-related species. 展开更多
关键词 Hepatitis B Hepatitis B virus nonhuman host Cross-species transmission Hepatitis B virus
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Bio-derived N-doped porous carbon as sulfur hosts for high performance lithium sulfur batteries 被引量:3
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作者 LIU Yan-yan YAN Li-jing +9 位作者 ZENG Xian-qing LI Ze-heng ZHOU Shu-dong DU Qiao-kun MENG Xiang-juan ZENG Xiao-min LING Min SUN Ming-hao QIAN Chao LIANG Cheng-du 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第6期1426-1434,共9页
Shuttle effect,poor conductivity and large volume expansion are the main factors that hinder the practical application of sulfur cathodes.Currently,rational structure designing of carbon-based sulfur hosts is the most... Shuttle effect,poor conductivity and large volume expansion are the main factors that hinder the practical application of sulfur cathodes.Currently,rational structure designing of carbon-based sulfur hosts is the most effective strategy to address the above issues.However,the preparation process of carbon-based sulfur hosts is usually complex and costly.Therefore,it is necessary to develop an efficient and cost-effective method to fabricate carbon hosts for high-performance sulfur cathodes.Herein,we reported the fabrication of a bio-derived nitrogen doped porous carbon materials(BNPC)via a molten-salt method for high performance sulfur cathodes.The long-range-ordered honeycomb structure of BNPC is favorable for the trapping of polysulfide(PS)species and accommodates the volumetric variation of sulfur during cycling,while the high graphitization degree of BNPC favors the redox kinetics of sulfur cathodes.Moreover,the nitrogen doping content not only enhances the electrical conductivity of BNPC,but also provides ample anchoring sites for the immobilization of PS,which plays a key role in suppressing the shuttle effect.As a result,the S@BNPC cathode exhibits a high initial specific capacity of 1189.4 mA·h/g at 0.2C.After 300 cycles,S@BNPC still maintains a capacity of 703.2 mA·h/g which corresponds to a fading rate of 0.13%per cycle after the second cycle.This work offers vast opportunities for the large-scale application of high performance carbon-based sulfur hosts. 展开更多
关键词 lithium sulfur batteries high graphitization nitrogen doping sulfur hosts shuttle effect
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Survey and examination of the potential alternative hosts of Villosiclava virens, the pathogen of rice false smut, in China 被引量:1
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作者 DENG Qi-de YONG Ming-li +4 位作者 LI Dan-yang LAI Chao-hui CHEN Hong-ming FAN Jing HU Dong-wei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第7期1332-1337,共6页
Rice false smut is caused by ascomycete Villosiclava virens, whose potential alternative hosts have been assumed previ- ously. Here its potential alternative hosts were surveyed and identified from 2008 to 2013 in the... Rice false smut is caused by ascomycete Villosiclava virens, whose potential alternative hosts have been assumed previ- ously. Here its potential alternative hosts were surveyed and identified from 2008 to 2013 in the main rice-growing regions in China. Two common weeds in paddy fields, Digitaria sanguinalis Scop. and Echinochloa crusgalli (L.) Beauv., were found to present the similar symptoms to smut diseases in a few individuals in 2012 and 2013 in Zhejiang and Sichuan provinces of China, respectively. After the examinations of the spore morphology, their infection and extension mode in hosts, pathogen cell wall components, and molecular identification, the two pathogens were identified to be the Basidiomycetes, Ustilago syntherismae and Ustilago trichophora, respectively. So far there has been no alternative host of V. virens to be identified in China. These suggest that the alternative hosts of V. virens, if they do exist, are not possible to play an important role in the pathogen life cycle and the disease epidemics. 展开更多
关键词 alternative host Villosiclava virens Digitaria sanguinalis Scop. Echinochloa crusgalli (L.) Beauv. Ustilagospp. rice false smut
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Why cuckoos should parasitize parrotbills by laying eggs randomly rather than laying eggs matching the egg appearance of parrotbill hosts? 被引量:2
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作者 Canchao Yang Fugo Takasu +1 位作者 Wei Liang Anders P Moller 《Chinese Birds》 CSCD 2015年第2期53-59,共7页
The coevolutionary interaction between cuckoos and their hosts has been studied for a long time, but to date some puzzles still remain unsolved. Whether cuckoos parasitize their hosts by laying eggs randomly or matchi... The coevolutionary interaction between cuckoos and their hosts has been studied for a long time, but to date some puzzles still remain unsolved. Whether cuckoos parasitize their hosts by laying eggs randomly or matching the egg morphs of their hosts is one of the mysteries of the cuckoo problem. Scientists tend to believe that cuckoos lay eggs matching the appearance of host eggs due to selection caused by the ability of the hosts to recognize their own eggs.In this paper, we first review previous empirical studies to test this mystery and found no studies have provided direct evidence of cuckoos choosing to parasitize host nests where egg color and pattern match. We then present examples of unmatched cuckoo eggs in host nests and key life history traits of cuckoos, e.g. secretive behavior and rapid egg-laying and link them to cuckoo egg laying behavior. Finally we develop a conceptual model to demonstrate the egg laying behaviour of cuckoos and propose an empirical test that can provide direct evidence of the egg-laying properties of female cuckoos. We speculate that the degree of egg matching between cuckoo eggs and those of the host as detected by humans is caused by the ability of the hosts to recognize their own eggs, rather than the selection of matching host eggs by cuckoos. The case of Common Cuckoos(Cuculus canorus) and their parrotbill hosts(Paradoxornis alphonsianus), where it has been shown that both have evolved polymorphic eggs(mainly blue and white), was used to develop a conceptual model to demonstrate why cuckoos should utilize parrotbill hosts by laying eggs randomly rather than laying eggs matching the appearance of host eggs.In conclusion, we found no evidence for the hypothesis that cuckoos lay eggs based on own egg color matching that of the parrotbill-cuckoo system. We argue theoretically that laying eggs matching those of the hosts in this system violates a key trait of the life history of cuckoos and therefore should be maladaptive. 展开更多
关键词 host imprint Egg laying behavior Egg color host selection Common cuckoo Egg polymorphy
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Hosts文件的作用与应用 被引量:1
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作者 赵晓丽 《山西气象》 2005年第3期15-17,共3页
本文通过对临汾市气象部门办公信息网中多个站、多次出现的问题的分析,找出原因所在,并针对性的做了分析并提出了解决的方法。介绍了HOSTS文件的功能,并根据HOSTS文件的功能,对我们工作中出现的问题给予解决和指导,在保障网络畅通、网... 本文通过对临汾市气象部门办公信息网中多个站、多次出现的问题的分析,找出原因所在,并针对性的做了分析并提出了解决的方法。介绍了HOSTS文件的功能,并根据HOSTS文件的功能,对我们工作中出现的问题给予解决和指导,在保障网络畅通、网络安全中都起到重要作用。 展开更多
关键词 hosts文件 LOTUS网 IP地址
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