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River width and depth as key factors of diurnal activity energy expenditure allocation for wintering Spot-billed Ducks in the Xin'an River Basin
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作者 Chao Yu Xuying Lu +3 位作者 Deli Sun Mengnan Chu Xueyun Li Qun Li 《Avian Research》 SCIE CSCD 2024年第1期116-122,共7页
Rivers are important habitats for wintering waterbirds.However,they are easily influenced by natural and human activities.An important approach for waterbirds to adapt to habitats is adjusting the activity time and en... Rivers are important habitats for wintering waterbirds.However,they are easily influenced by natural and human activities.An important approach for waterbirds to adapt to habitats is adjusting the activity time and energy expenditure allocation of diurnal behavior.The compensatory foraging hypothesis predicts that increased energy expenditure leads to longer foraging time,which in turn increases food intake and helps maintain a constant energy balance.However,it is unclear whether human-disturbed habitats result in increased energy expenditure related to safety or foraging.In this study,the scan sample method was used to observe the diurnal behavior of the wintering Spot-billed Duck(Anas poecilorhyncha) in two rivers in the Xin’an River Basin from October 2021 to March 2022.The allocation of time and energy expenditure for activity in both normal and disturbed environments was calculated.The results showed that foraging accounted for the highest percentage of time and energy expenditure.Additionally,foraging decreased in the disturbed environment than that in the normal environment.Resting behavior showed the opposite trend,while other behaviors were similar in both environments.The total diurnal energy expenditure of ducks in the disturbed environment was greater than that in the normal environment,with decreased foraging and resting time percentage and increased behaviors related to immediate safety(swimming and alert) and comfort.These results oppose the compensatory foraging hypothesis in favor of increased security.The optimal diurnal energy expenditure model included river width and water depth,which had a positive relationship;an increase in either of these two factors resulted in an increase in energy expenditure.This study provides a better understanding of energy allocation strategies underlying the superficial time allocation of wintering waterbirds according to environmental conditions.Exploring these changes can help understand the maximum fitness of wintering waterbirds in response to nature and human influences. 展开更多
关键词 Diurnal behavior activities River factors Time and energy expenditure allocation Wintering Spot-billed Duck Xin’an River Basin
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Soil bacterial and fungal communities resilience to long-term nitrogen addition in subtropical forests in China
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作者 Xinlei Fu Yunze Dai +3 位作者 Jun Cui Pengfei Deng Wei Fan Xiaoniu Xu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期95-108,共14页
Atmospheric nitrogen(N)deposition is predicted to increase,especially in the subtropics.However,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have no... Atmospheric nitrogen(N)deposition is predicted to increase,especially in the subtropics.However,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have not been clarified.A long-term nutrient addition experiment was conducted in a subtropical evergreen old-growth forest in China.The four treatments were:control,low N(50 kg N ha^(-1)a^(-1)),high N(100 kg N ha^(-1)a^(-1)),and combined N and phosphorus(P)(100 kg N ha^(-1)a^(-1)+50 kg P ha^(-1)a^(-1)).Metagenomic sequencing characterized diversity and composition of soil microbial communities and used to construct bacterial/fungal co-occurrence networks.Nutrient-treated soils were more acidic and had higher levels of dissolved organic carbon than controls.There were no significant differences in microbial diversity and community composition across treatments.The addition of nutrients increased the abundance of copiotrophic bacteria and potentially beneficial microorganisms(e.g.,Gemmatimonadetes,Chaetomium,and Aureobasidium).Low N addition increased microbiome network connectivity.Three rare fungi were identified as module hubs under nutrient addition,indicating that low abundance fungi were more sensitive to increased nutrients.The results indicate that the overall composition of microbial communities was stable but not static to long-term N addition.Our findings provide new insights that can aid predictions of the response of soil microbial communities to long-term N addition. 展开更多
关键词 Long-term nitrogen addition Old-growth subtropical forest METAGENOMICS Beneficial microorganisms Co-occurrence network
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Analysis on the Growth Condition of Cunninghamia lanceolata Plantation in Lingnan Forest Farm
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作者 Jun CUI Renhao FANG 《Agricultural Biotechnology》 2024年第3期69-74,共6页
[Objectives]This study was conducted to provide good basic research data for Cunninghamia lanceolata plantations in southern Anhui,so as to improve local ecological,economic and social benefits.[Methods]A 22-year-old ... [Objectives]This study was conducted to provide good basic research data for Cunninghamia lanceolata plantations in southern Anhui,so as to improve local ecological,economic and social benefits.[Methods]A 22-year-old near-mature C.lanceolata plantation in Lingnan Forest Farm,Xiuning County,Huangshan City,Anhui Province was investigated and analyzed by sample plot survey.[Results]The average DBH value of the C.lanceolata plantation at the lower slope was the largest,24.7%and 19.2%higher than those at the upper and middle slopes,respectively.The average single plant wood volume at the lower slope was 47.6%and 49.1%higher than those in the upper and middle slopes,respectively.However,the average tree heights at various slope positions showed little difference.Meanwhile,all the indexes showed the phenomenon of semi-shady slope>sunny slope>shady slope under different slope directions.Among them,the effect of slope position on DBH was extremely significant,but the effect of slope direction on DBH was not significant,and slope position,slope direction and the interaction of slope direction and slope position had no significant effects on the tree height of the C.lanceolata plantation.In addition,slope direction and slope position had extremely significant effects on single plant wood volume.From the overall growth situation of the C.lanceolata plantation in Lingnan Forest Farm,the slope position factor had greater effects on various indexes of forest growth than the slope direction factor,mainly manifested in that the lower slope was better than the middle slope,and the middle slope position was better than the upper slope,while although slope direction had some effect on the growth of the C.lanceolata plantation,the influence degree was not as significant as that of slope position.[Conclusions]This study provides some reference for the adjustment and optimization,development and renewal of C.lanceolata plantation structure in the later period in this area,as well as some data support for other theoretical research on economic forests. 展开更多
关键词 Diameter at breast height Tree height Single plant wood volume Slope direction Slope position
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Application of Modern Construction Art in Landscape Architecture Planning and Design
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作者 JIANG Yuanyuan 《Journal of Landscape Research》 2024年第3期43-47,共5页
The continuous progress of urbanization has driven the continuous development and innovation of landscape planning and design.Focused on the important design method of modern construction art,this study analyzed its c... The continuous progress of urbanization has driven the continuous development and innovation of landscape planning and design.Focused on the important design method of modern construction art,this study analyzed its concepts and characteristics,and made deep exploration to its application in landscape planning and design.The results indicated that modern construction art had a significant impact on landscape spatial planning and layout,spatial design forms,and spatial ornaments.The use of modern construction art concepts could make landscape design more scientific,artistic,and humane,creating higher quality leisure and entertainment venues for audiences. 展开更多
关键词 Landscape architecture design Modern construction art Construction Art
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Intraspecific Polymorphism of Rice Frog,Fejervarya multistriata(Anura: Ranidae),in Lingnan,Huangshan,China 被引量:2
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作者 Diancheng YANG Lifang PENG +1 位作者 Jingcheng XU Song HUANG 《Asian Herpetological Research》 SCIE CSCD 2017年第1期22-26,共5页
Many anuran species exhibit striking color and/or pattern polymorphisms. We sampled 599 adult rice frogs, Fejervarya multistriata, from a rice paddy in the periphery of the Lingnan Nature Reserve (Huangshan, Anhui).... Many anuran species exhibit striking color and/or pattern polymorphisms. We sampled 599 adult rice frogs, Fejervarya multistriata, from a rice paddy in the periphery of the Lingnan Nature Reserve (Huangshan, Anhui). We recognized ten morphs based on three relatively stable and distinct morphological characters: dorsal ground color (green or gray), middorsal stripe (absence, wide, or narrow), occipital rusty spot (absence or presence). The grey individuals are more common and larger than the green individuals (frequency 88.1 vs. 11.9%, respectively) and (SVL 39.4-36.6 vs. 35.7-34.6 mm, respectively). There is a higher proportion of individuals with a middorsal stripe (59.7%) while absence of the occipital rusty spot is more common in the population (82.3%). We expect additional studies in different habitat types would help build our understanding of the relationship between color polymorphism and habitat, geography, and climate. 展开更多
关键词 dorsal ground color middorsal stripe occipital rusty spot frequency body size
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Huangshan population of Chinese Zacco platypus (Teleostei, Cyprinidae) harbors diverse matrilines and high genetic diversity 被引量:2
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作者 Xin ZHENG Tian-Qi ZHOU +7 位作者 Tao WAN Anabel PERDICES Jin-Quan YANG Xin-Sheng TANG Zheng-Ping WANG Li-Qun HUANG Song HUANG Shun-Ping HE 《Zoological Research》 CAS CSCD 2016年第2期103-109,共7页
Six main mitochondrial DNA (mtDNA) lineages have been described in minnow (Zacco platypus) samples obtained from northern, western and southern China Perdices et al. (2004) predicted that further sampling of oth... Six main mitochondrial DNA (mtDNA) lineages have been described in minnow (Zacco platypus) samples obtained from northern, western and southern China Perdices et al. (2004) predicted that further sampling of other tributaries might discover more lineages of this species. In this study, we collected 26 Zacco platypus individuals in the Huangshan area of eastern China and determined the cytochrome b (cytb) sequence variations. Combined with reported data in GenBank, we identified ten matrilines (Zacco A-J) in a total of 169 samples, with relatively high molecular divergence found among them. The Huangshan population had the greatest genetic variation among all sampled regions and hosted six of the ten matrilines. Our results highlight the significance of the Huangshan area for the conservation of Zacco platypus. 展开更多
关键词 Zacco platypus Matriline Huangshan PHYLOGENETICS Diversity
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Development of innovation-driven green economy in Huangshan City, China
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作者 FANG Liang WEN Qian SUN Song-yan 《Ecological Economy》 2018年第4期242-248,共7页
With the increasingly prominent problems of ecology, environment and resources in China, green economy development is becoming more and more urgent. Innovation has become the key driving force of economic development.... With the increasingly prominent problems of ecology, environment and resources in China, green economy development is becoming more and more urgent. Innovation has become the key driving force of economic development. Economic development of Huangshan City should take the road of "green development " and combine economic development with ecological protection. This paper designs the measurement index of innovation and green economic development, and makes an empirical analysis based on the data of innovation and green economic development in Huangshan City from 2005 to 2016. It is concluded that the index of innovation and green economic development in Huangshan City shows an increasing trend. Innovation has a positive role in promoting green economic development in Huangshan City. Therefore, Huangshan City should strengthen regional innovation management, create regional innovation environment, strengthen cooperation between industry, University and research, increase support for green innovation, promote technological innovation of recycling, and promote the construction of circular economy. 展开更多
关键词 innovation-driven green ECONOMY driving EFFECT Huangshan CITY
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Flexible nest site selection of the endangered Oriental Storks(Ciconia boyciana):Trade-off from adaptive strategies 被引量:3
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作者 Lei Cheng Lizhi Zhou +2 位作者 Chao Yu Zhenhua Wei Chunhua Li 《Avian Research》 SCIE CSCD 2023年第2期242-249,共8页
Nest site selection is a vital component of bird reproduction success,and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances.Understanding patterns of nest site selectio... Nest site selection is a vital component of bird reproduction success,and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances.Understanding patterns of nest site selection can provide insights into how species adapt to changes in their habitat and has important conservation implications.In this study,we used microhabitat variables and multi-scale data with a field survey of nest occurrence to determine nest site selection patterns and adaptive strategies of the breeding Oriental Storks(Ciconia boyciana)in different nest areas.Results demonstrate that the nest site microhabitat characteristics of the breeding Oriental Storks significantly differed among the three nesting areas,and nest height was higher in the middle and lower Yangtze River floodplain than in the Northeast China and Bohai Bay nest areas.The food resources and intensity of human disturbance had the greatest effects on the nest site selection of the breeding Oriental Storks.The intensity of human disturbance was positively correlated with the nest height of the breeding Oriental Storks in Bohai Bay and the middle and lower Yangtze River floodplain;however,nest height decreased with the abundance of food resources in the Northeast China nest area.Our findings indicate that the nest site selection patterns of Oriental Storks showed flexible adaptive strategies.In safer environments,nests were lower and closer to food resources,which allows parent storks to invest more in the nestlings.However,in areas where human activity was intense,nests were higher to ensure the safety of their offspring.Some measures that could be taken to improve the breeding habitat of Oriental Storks include increasing the percentage of wetland areas in nesting areas to enhance food resources availability and setting artificial nests at suitable heights in potential nesting grounds to encourage nesting.Finally,the establishment of soft barriers around the nesting areas could increase the safety of nests. 展开更多
关键词 Adaptive strategies Breeding range expansion Habitat characteristics Nest site selection Oriental storks
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Effects of Torreya grandis Root Rot on Seedling Growth and Screening of Its Chemical Control Agents
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作者 Lei ZHENG Xinyu RU +5 位作者 Ziyi WAN Chao HE Xiaoyu LI Caiyun LYU Li CHEN Zhibing WAN 《Agricultural Biotechnology》 CAS 2023年第5期108-113,共6页
[Objectives]This study was conducted to prevent the occurrence of root rot disease in Torreya grandis and improve the yield and quality of T.grandis.[Methods]One-year-old and two-year-old seedlings of Torreya grandis... [Objectives]This study was conducted to prevent the occurrence of root rot disease in Torreya grandis and improve the yield and quality of T.grandis.[Methods]One-year-old and two-year-old seedlings of Torreya grandis‘Xifei’and‘Cufei’were inoculated with the root rot pathogen Fusarium fujikuroi,and the changes in photosynthesis,chlorophyll content,malondialdehyde,and defense enzyme system(superoxide dismutase,peroxidase,and catalase)activity in leaves of T.grandis seedlings were investigated using water as a control.Meanwhile,the control effects of 80%carbendazim wettable powder,64%metalaxyl·mancozeb wettable powder,430 g/L tebuconazole suspension and 30%difenoconazole·cyproconazole EC on root rot in T.grandis were investigated.[Results]After inoculation with the pathogen F.fujikuroi,the net photosynthetic rates and transpiration rates in leaves of T.grandis‘Xifei’and‘Cufei’decreased,and the contents of chlorophyll decreased,while the contents of malondialdehyde increased,and the contents of superoxide dismutase and catalase increased with time.However,peroxidase showed a high activity in T.grandis‘Cufei’only,but a trend of"increasing-decreasing-increasing"in T.grandis‘Xifei’.Among the four chemical control agents,64%metalaxyl·mancozeb wettable powder had the best control effect on root rot of T.grandis caused by the pathogenic fungus F.fujikuroi.[Conclusions]The net photosynthetic rate,transpiration rate,chlorophyll content,malondialdehyde content,superoxide dismutase activity and catalase activity could all be used as screening indicators for T.grandis varieties resistant to root rot.Meanwhile,64%metalaxyl·mancozeb wettable powder could be used as a control agent for root rot on T.grandis. 展开更多
关键词 Torreya grandis Root rot disease Physiological and biochemical metabolism Chemical control
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Development Path of Innovation and Entrepreneurship Education in Universities Under the Digital Economy
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作者 Zhang Li Qingqing Yu 《Journal of Contemporary Educational Research》 2023年第10期113-119,共7页
With the development of digital technology and new models of digital economy,innovation and entrepreneurship education in colleges and universities is facing a new development situation.New methods such as online cour... With the development of digital technology and new models of digital economy,innovation and entrepreneurship education in colleges and universities is facing a new development situation.New methods such as online courses,digital platforms,and value co-creation have brought new opportunities and challenges to the content,mode,and mechanism of innovation and entrepreneurship education.This paper discusses the content and new opportunities of digital entrepreneurship,analyzes the differences between traditional entrepreneurship and digital entrepreneurship,and puts forward the strategy path of entrepreneurship education under the digital economy. 展开更多
关键词 Digital economy Entrepreneurship education Development path
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Uptake and accumulation of phenanthrene and pyrene in spiked soils by Ryegrass(Lolium perenne L.) 被引量:9
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作者 XU Sheng-you CHEN Ying-xu +3 位作者 LIN Qi WU Wei-xiang XUE Sheng-guo SHEN Chao-feng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第5期817-822,共6页
Phytoremediation has long been recognized as a cost-effective method for the removal of polycyclic aromatic hydrocarbons (PAHs) from soil. A study was conducted to investigate the uptake and accumulation of PAHs in ... Phytoremediation has long been recognized as a cost-effective method for the removal of polycyclic aromatic hydrocarbons (PAHs) from soil. A study was conducted to investigate the uptake and accumulation of PAHs in root and shoot of Lolium perenne L. Pot experiments were conducted with series of concentrations of 3.31-378.37 mg/kg for phenanthrene and those of 4.22-365.38 mg/kg for pyrene in a greenhouse. The results showed that both ryegrass roots and shoots did take up PAHs from spiked soils, and generally increased with increasing concentrations of PAH in soil. Bioconcentration factors(BCFs) of phenanthrene by shoots and roots were 0.24- 4.25 and 0.17-2.12 for the same treatment. BCFs of pyrene by shoots were 0.20-1.5, except for 4.06 in 4.32 mg/kg treatment, much lower than BCFs of pyrene by roots (0.58-2.28). BCFs of phenanthrene and pyrene tended to decrease with increasing concentrations of phenanthrene and pyrene in soil. Direct uptake and accumulation of these compounds by Lolium perenne L. was very low compared with the other loss pathways, which meant that plant-promoted microbial biodegradation might be the main contribution to plant-enhanced removal of phenanthrene and pyrene in soil. However, the presence of Lolium perenne L. significantly enhanced the removal of phenanthrene and pyrene in spiked soil. At the end of 60 d experiment, the extractable concentrations of phenanthrene and pyrene were lower in planted soil than in non-planted soil, about 83.24%-91.98% of phenanthrene and 68.53%-84.10% of pyrene were removed from soils, respectively. The results indicated that the removal of PAHs in contaminated soils was a feasible approach by using Lolium perenne L. 展开更多
关键词 PHYTOREMEDIATION polycyclic aromatic hydrocarbons(PAHs) phenanthrene and pyrene uptake and accumulation
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Removal of Pyrene from Contaminated Soils by White Clover 被引量:5
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作者 XU Sheng-You CHEN Ying-Xu +4 位作者 LIN Kuang-Fei CHEN Xin-Cai LIN Qi LI Feng WANG Zhao-Wei 《Pedosphere》 SCIE CAS CSCD 2009年第2期265-272,共8页
Phytoremediation has been used as an emerging technology for remediation of soil contamination with polycyclic aromatic hydrocarbons(PAHs),ubiquitous persistent environmental pollutants derived from natural and anthro... Phytoremediation has been used as an emerging technology for remediation of soil contamination with polycyclic aromatic hydrocarbons(PAHs),ubiquitous persistent environmental pollutants derived from natural and anthropogenic processes,in the last decade.In this study,a pot experiment was conducted to investigate the potential of phytoremediation of pyrene from spiked soils planted with white clover(Trifolium repens)in the greenhouse with a series of pyrene concentrations ranging from 4.22 to 365.38 mg kg-1.The results showed that growth of white clover on pyrenecontaminated soils was not affected.The removal of pyrene from the spiked soils planted with white clover was obviously higher than that from the unplanted soils.At the end of the experiment(60 d),the average removal ratio of pyrene in the spiked soils with white clover was 77%,which was 31%and 57%higher than those of the controls with or without micobes, respectively.Both roots and shoots of white clover took up pyrene from the spiked soils and pyrene uptake increased with the soil pyrene concentration.However,the plant-enhanced dissipation of soil pyrene may be the result of plant-promoted microbial degradation and direct uptake and accumulation of pyrene by white clover were only a small part of the pyrene dissipation.Bioconcentration factors of pyrene(BCFs,ratio of pyrene,on a dry weight basis,in the plant to that in the soil)tended to decrease with increase in the residual soil pyrene concentration.Therefore,removal of pyrene in the contaminated soils was feasible using white clove. 展开更多
关键词 microbial degradation PHYTOREMEDIATION plant uptake and accumulation PYRENE white clover
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Recent advances in acid-resistant zeolite T membranes for dehydration of organics 被引量:4
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作者 Yiwei Luo Waseem Raza +2 位作者 Jianhua Yang Liangqing Li Ying Lu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第6期1449-1457,共9页
Zeolite membranes offer outstanding potentials in separation of many molecular mixtures due to their molecular sieving selectivity and the high thermal and mechanical stability that allow them to operate at harsh cond... Zeolite membranes offer outstanding potentials in separation of many molecular mixtures due to their molecular sieving selectivity and the high thermal and mechanical stability that allow them to operate at harsh conditions.Development of durable and high separation performance membranes with lower fabrication and operation cost are highly demanded for industrial applications. Zeolite T membrane possesses good acid-resistance with excellent hydrophilic properties as compared to NaA zeolite membrane and can be extended to industrial organic dehydrations under an acidic environment. In the present review the research advances in development of zeolite T membranes for the dehydration of organic mixtures in acidic conditions are summarized. Especially the low temperature synthesis, and epitaxial growth of the zeolite membrane with high performance are well addressed, besides emphasis is particularly placed on ensemble synthesis of hollow fiber zeolite T membrane module and its future prospects for industrial separations. 展开更多
关键词 DEHYDRATION of ORGANICS EPITAXIAL growth ZEOLITE T MEMBRANE MEMBRANE PERVAPORATION
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A New Species of the Genus Thermophis(Serpentes: Colubridae) from Shangri-La, Northern Yunnan, China, with a Proposal for an Eclectic Rule for Species Delimitation 被引量:5
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作者 Lifang PENG Changhu LU +2 位作者 Song HUANG Peng GUO Yaping ZHANG 《Asian Herpetological Research》 SCIE 2014年第4期228-239,共12页
The hot-spring snakes,Thermophis, were previously known only from the Tibet Autonomous Region and Western Sichuan, China. During the past two years, three adult hot-spring snakes (2 females, 1 male) were sampled in ... The hot-spring snakes,Thermophis, were previously known only from the Tibet Autonomous Region and Western Sichuan, China. During the past two years, three adult hot-spring snakes (2 females, 1 male) were sampled in Shangri-La, northern Yunnan, China, thus expanding their known distribution region towards the southeast. This site is the southeastern-most corner of the Tibetan Plateau and the southernmost tip of the Hengduan Mountains (Mts.). Phylogenetic analysis of mitochondrial (mt) and nuclear (n) DNA segments suggested that the three specimens belong to the genus ofThermophis. Morphologically, the new species is more similar toT. zhaoermii. However, it is distinguished fromT.zhaoermiiin the number of maxillary teeth (15), distance between the two eyes/head width, rostral width/height, mental width/height, in one character limited to female: head width/length, and in four characters restricted to male: occurrence of the reduction from 10 to 8 (8 to 6, 6 to 4) scales in each dorsal row on the tail. There are differences in morphology, genetics (mtDNA, nDNA), and geography between the putative new species andT.zhaoermii,the new species meets our proposed eclectic and feasible "four-differences" rule. 展开更多
关键词 morphology PHYLOGENETICS "four-differences" rule Thermophis Shangrila sp. nov.
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Characterization of hot deformation and microstructure evolution of a new metastableβtitanium alloy 被引量:4
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作者 Zhao-qi CHEN Li-juan XU +5 位作者 Shou-zhen CAO Jian-kai YANG Yun-fei ZHENG Shu-long XIAO Jing TIAN Yu-yong CHEN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第5期1513-1529,共17页
The hot deformation characteristics of as-forged Ti−3.5Al−5Mo−6V−3Cr−2Sn−0.5Fe−0.1B−0.1C alloy within a temperature range from 750 to 910℃and a strain rate range from 0.001 to 1 s^(-1) were investigated by hot compre... The hot deformation characteristics of as-forged Ti−3.5Al−5Mo−6V−3Cr−2Sn−0.5Fe−0.1B−0.1C alloy within a temperature range from 750 to 910℃and a strain rate range from 0.001 to 1 s^(-1) were investigated by hot compression tests.The stress−strain curves show that the flow stress decreases with the increase of temperature and the decrease of strain rate.The microstructure is sensitive to deformation parameters.The dynamic recrystallization(DRX)grains appear while the temperature reaches 790℃at a constant strain rate of 0.001 s^(-1) and strain rate is not higher than 0.1 s^(-1) at a constant temperature of 910℃.The work-hardening rateθis calculated and it is found that DRX prefers to happen at high temperature and low strain rate.The constitutive equation and processing map were obtained.The average activation energy of the alloy is 242.78 kJ/mol and there are few unstable regions on the processing map,which indicates excellent hot workability.At the strain rate of 0.1 s^(-1),the stress−strain curves show an abnormal shape where there are two stress peaks simultaneously.This can be attributed to the alternation of hardening effect,which results from the continuous dynamic recrystallization(CDRX)and the rotation of DRX grains,and dynamic softening mechanism. 展开更多
关键词 metastableβtitanium alloy hot deformation behavior microstructure evolution abnormal flow behavior
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Phylogenetic Analyses Reveal a Unique Species of Elaphe(Serpentes,Colubridae)New to Science 被引量:4
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作者 LING Chen LIU Shaoying +4 位作者 HUANG Song Frank T.Burbrink GUO Peng SUN Zhiyu ZHAO Jie 《Asian Herpetological Research》 SCIE 2010年第2期90-96,共7页
The snakes comprising the monophyletic group referred to as ratsnakes are found throughout Asia,Europe and the New World.Recently,three snake samples likely belonging to the ratsnakes were collected in Zoige County,Si... The snakes comprising the monophyletic group referred to as ratsnakes are found throughout Asia,Europe and the New World.Recently,three snake samples likely belonging to the ratsnakes were collected in Zoige County,Sichuan Province,China.Species identity was difficult to delimit morphologically because the specimens were juveniles and partially damaged.Subsequently,a molecular phylogenetic approach was used.Portions of three mitochondrial genes(cyt b,ND4 and 12S rRNA) were sequenced and analyzed.The results showed that they were sister to the genus Elaphe.Very little genetic variation was found among the three samples.The minimum genetic distances between these samples and those within Elaphe were greater than any currently recognized species within the genus.We conclude that this likely represents a new species within the genus Elaphe.Adult specimens and a morphologic description are needed for further study. 展开更多
关键词 Elaphe ratsnake phylogenetic analysis mitochondrial gene genetic distance
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Synthesis of Environmentally Friendly Magnesium Linoleate Detergent 被引量:2
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作者 Wang Yonglei Li Haiyun +2 位作者 Fang Hongxia Ni Zhifei Zhao Lele 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2014年第1期96-100,共5页
This paper mainly covers a method for preparing a highly alkaline magnesium linoleate solution with a total base number(TBN) value of 328 mg KOH/g using linoleic acid as the biodegradable raw material, which can subst... This paper mainly covers a method for preparing a highly alkaline magnesium linoleate solution with a total base number(TBN) value of 328 mg KOH/g using linoleic acid as the biodegradable raw material, which can substitute for traditional lubricant detergents as an environmentally friendly detergent. Reaction conditions, including the molar ratio of magnesium oxide to linoleic acid, the molar ratio of methanol to magnesium oxide, the carbonation temperature, the molar ratio of water to magnesium oxide, the flow rate of CO2 gas and the duration for injection of CO2 to magnesium oxide system, were optimized. 展开更多
关键词 lubricant detergent magnesium linoleate high total base number BIODEGRADATION
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New Record of Lycodon liuchengchaoi in Anhui 被引量:5
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作者 Liang ZHANG Li-Fang PENG +3 位作者 Lei YU Zheng-Ping WANG Li-Qun HUANG Song HUANG 《Zoological Research》 CAS CSCD 2015年第3期178-180,共3页
One juvenile and one adult female wolf snake(Colubridae: Lycodon) were sampled at Yixian and Fuxi, Huangshan, Anhui, China in the summer of 2011 and 2012, respectively. The two specimens were identified as Lycodon ... One juvenile and one adult female wolf snake(Colubridae: Lycodon) were sampled at Yixian and Fuxi, Huangshan, Anhui, China in the summer of 2011 and 2012, respectively. The two specimens were identified as Lycodon liuchengchaoi based on external morphology and molecular data. This is a new reptile record in Anhui Province. In our laboratory, four eggs were laid and three neonates were hatched successfully. This is the first record of the laying and incubation of L. liuchengchaoi eggs. The five specimens were deposited at the Museum of Huangshan University(HUM20140001) and Guangdong Entomological Institute(HB-lcfsp12613, HB-lcfsp-ch1~3). 展开更多
关键词 REPTILE Lycodon liuchengchaoi INCUBATION New record
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CurveNet:Curvature-Based Multitask Learning Deep Networks for 3D Object Recognition 被引量:2
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作者 A.A.M.Muzahid Wanggen Wan +2 位作者 Ferdous Sohel Lianyao Wu Li Hou 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第6期1177-1187,共11页
In computer vision fields,3D object recognition is one of the most important tasks for many real-world applications.Three-dimensional convolutional neural networks(CNNs)have demonstrated their advantages in 3D object ... In computer vision fields,3D object recognition is one of the most important tasks for many real-world applications.Three-dimensional convolutional neural networks(CNNs)have demonstrated their advantages in 3D object recognition.In this paper,we propose to use the principal curvature directions of 3D objects(using a CAD model)to represent the geometric features as inputs for the 3D CNN.Our framework,namely CurveNet,learns perceptually relevant salient features and predicts object class labels.Curvature directions incorporate complex surface information of a 3D object,which helps our framework to produce more precise and discriminative features for object recognition.Multitask learning is inspired by sharing features between two related tasks,where we consider pose classification as an auxiliary task to enable our CurveNet to better generalize object label classification.Experimental results show that our proposed framework using curvature vectors performs better than voxels as an input for 3D object classification.We further improved the performance of CurveNet by combining two networks with both curvature direction and voxels of a 3D object as the inputs.A Cross-Stitch module was adopted to learn effective shared features across multiple representations.We evaluated our methods using three publicly available datasets and achieved competitive performance in the 3D object recognition task. 展开更多
关键词 3D shape analysis convolutional neural network DNNs object classification volumetric CNN
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Experimental Study on Seepage Characteristics of a Soil-Rock Mixture in a Fault Zone 被引量:2
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作者 Pengfei Wang Xiangyang Zhang 《Fluid Dynamics & Materials Processing》 EI 2022年第2期271-283,共13页
A mixture of fault gouge and rubble taken out from a fault zone is used to prepare a S-RM(Soil-Rock Mixture)sample with rock block proportions of 20%,30%,40%,50%,60%and 70%,respectively.A GDS triaxial test system is u... A mixture of fault gouge and rubble taken out from a fault zone is used to prepare a S-RM(Soil-Rock Mixture)sample with rock block proportions of 20%,30%,40%,50%,60%and 70%,respectively.A GDS triaxial test system is used accordingly to measure the seepage characteristics of such samples under different loading and unloading confining pressures in order to determine the variation law of the permeability coefficient.The test results show that:(1)The permeability coefficient of the S-RM samples decreases as the pressure increases,and the decrease rate of this coefficient in the initial stage of confining pressure loading is obviously higher than in the semi-late period;(2)The permeability coefficient at different confining pressure levels presents a common trend as the rock block proportion is increased,i.e.,it decreases first then it increases(the permeability coefficient of the sample with rock block proportion 40%being the smallest,70%the largest);(3)In the stage of confining pressure unloading,the recovery degree of the permeability coefficient grows with the increase of rock block proportion(the recovery rate of S-RM sample with rock block proportion 70%reaches 50.2%);(4)In the stage of confining pressure loading and unloading,the sensitivity of the permeability coefficient to the rock block proportion displays the inverse“Z”variation rule(when rock block proportion reaches 60%,the sensitivity is highest);(5)In the stage of confining pressure loading,the relationship between the permeability coefficient and confining pressure can be described by an exponential relationship. 展开更多
关键词 Fault zone rock block proportion soil-rock mixture confining pressure loading and unloading seepage characteristic
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