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The Completeness of Accreting Neutron Star Binary Candidates from the Chinese Space Station Telescope
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作者 Hao Shen Shun-Yi Lan Xiang-Cun Meng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第9期28-36,共9页
A neutron star(NS)has many extreme physical conditions,and one may obtain some important information about an NS via accreting neutron star binary(ANSB)systems.The upcoming Chinese Space Station Telescope(CSST)provide... A neutron star(NS)has many extreme physical conditions,and one may obtain some important information about an NS via accreting neutron star binary(ANSB)systems.The upcoming Chinese Space Station Telescope(CSST)provides an opportunity to search for a large sample of ANSB candidates.Our goal is to check the completeness of the potential ANSB samples from CSST data.In this paper,we generate some ANSBs and normal binaries under the CSST photometric system by binary evolution and binary population synthesis method and use a machine learning method to train a classification model.Although the Precision(94.56%)of our machine learning model is as high as before study,the Recall is only about 63.29%.The Precision/Recall is mainly determined by the mass transfer rate between the NSs and their companions.In addition,we also find that the completeness of ANSB samples from CSST photometric data by the machine learning method also depends on the companion mass and the age of the system.ANSB candidates with a low initial mass companion star(0.1 M_(⊙)to 1 M_(⊙))have a relatively high Precision(94.94%)and high Recall(86.32%),whereas ANSB candidates with a higher initial mass companion star(1.1 M_(⊙)to 3 M_(⊙))have similar Precision(93.88%)and quite low Recall(42.67%).Our results indicate that although the machine learning method may obtain a relatively pure sample of ANSBs,a completeness correction is necessary for one to obtain a complete sample. 展开更多
关键词 stars:neutron X-rays:binaries methods:analytical
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Medcheck:A novel software for automated de-formulation of traditional Chinese medicine(TCM)prescriptions by liquid chromatography-mass spectrometry
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作者 Xiao-lan Li Jian-qing Zhang +7 位作者 Yun Li Xuan-jing Shen Huan-ya Yang Lin Yang Meng Xu Qi-rui Bi Chang-liang Yao De-an Guo 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第6期930-932,共3页
Prescriptions are the main clinical application of traditional Chinese medicines(TCMs).Common forms include Chinese patent medicines,Kampo formulas,and hospital decoctions.A new pre-scription called“famous classical ... Prescriptions are the main clinical application of traditional Chinese medicines(TCMs).Common forms include Chinese patent medicines,Kampo formulas,and hospital decoctions.A new pre-scription called“famous classical formulas”is recently developed and expected to boom in the market.Identifying constituent me-dicinal plants in prescriptions is critical for new drug development and quality control[1],which could avoid safety issues from adulteration or substandard ingredients,as seen in the notorious Longdan Xiegan Pill event. 展开更多
关键词 MEDICINES FORMULATION PRESCRIPTION
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Retention of harvest residues promotes the accumulation of topsoil organic carbon by increasing particulate organic carbon in a Chinese fir plantation
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作者 Jiamin Yang Ke Huang +5 位作者 Xin Guan Weidong Zhang Renshan Li Longchi Chen Silong Wang Qingpeng Yang 《Forest Ecosystems》 SCIE CSCD 2024年第5期720-727,共8页
Background As commonly used harvest residue management practices in subtropical plantations,stem only harvesting(SOH)and whole tree harvesting(WTH)are expected to affect soil organic carbon(SOC)content.However,knowled... Background As commonly used harvest residue management practices in subtropical plantations,stem only harvesting(SOH)and whole tree harvesting(WTH)are expected to affect soil organic carbon(SOC)content.However,knowledge on how SOC and its fractions(POC:particulate organic carbon;MAOC:mineral-associated organic carbon)respond to different harvest residue managements is limited.Methods In this study,a randomized block experiment containing SOH and WTH was conducted in a Chinese fir(Cunninghamia lanceolata)plantation.The effect of harvest residue management on SOC and its fractions in topsoil(0–10cm)and subsoil(20–40cm)was determined.Plant inputs(harvest residue retaining mass and fine root biomass)and microbial and mineral properties were also measured.Results The responses of SOC and its fractions to different harvest residue managements varied with soil depth.Specifically,SOH enhanced the content of SOC and POC in topsoil with increases of 15.9%and 29.8%,respectively,compared with WTH.However,SOH had no significant effects on MAOC in topsoil and SOC and its fractions in subsoil.These results indicated that the increase in POC induced by the retention of harvest residue was the primary contributor to SOC accumulation,especially in topsoil.The harvest residue managements affected SOC and its fractions through different pathways in topsoil and subsoil.The plant inputs(the increase in fine root biomass induced by SOH)exerted a principal role in the SOC accumulation in topsoil,whereas mineral and microbial properties played a more important role in regulating SOC dynamics than plants inputs in subsoil.Conclusion The retention of harvest residues can promote SOC accumulation by increasing POC,and is thus suggested as an effective technology to enhance the soil carbon sink for mitigating climate change in plantation management. 展开更多
关键词 Chinese fir plantation Soil organic carbon Particulate organic carbon Mineral-associated organic carbon Harvest residue management
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On the Identification of N-rich Metal-poor Field Stars with Future Chinese Space Station Telescope
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作者 Jiajun Zhang Baitian Tang +6 位作者 Jiang Chang Xiangxiang Xue JoséGFernández-Trincado Chengyuan Li Long Wang Hao Tian Yang Huang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期151-164,共14页
During the long term evolution of globular clusters(GCs), some member stars are lost to the field. The recently found nitrogen-rich(N-rich) metal-poor field stars are promising candidates of these GC escapees, since N... During the long term evolution of globular clusters(GCs), some member stars are lost to the field. The recently found nitrogen-rich(N-rich) metal-poor field stars are promising candidates of these GC escapees, since N enhancement is the fingerprint of chemically enhanced populations in GCs. In this work, we discuss the possibility of identifying N-rich metal-poor field stars with the upcoming Chinese Space Station Telescope(CSST). We focus on the main survey camera with NUV, u, g, r, i, z, y filters and slitless spectrograph with a resolution about 200.The combination of UV sensitive equipment and prominent N-related molecular lines in the UV band bodes well for the identification: the color–color diagram of(u-g) versus(g-r) is capable of separating N-rich field stars from normal halo stars, if metallicity can be estimated without using the information on u-band photometry.Besides, the synthetic spectra show that a signal-to-noise ratio of 10 is sufficient to identify N-rich field stars. In the near future, a large sample of N-rich field stars found by CSST, combined with state-of-the-art N-body simulations will be crucial to deciphering GC-Galaxy co-evolution. 展开更多
关键词 stars:chemically peculiar stars:abundances techniques:photometric techniques:spectroscopic
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Genetic analyses of ancient tea trees provide insights into the breeding history and dissemination of Chinese Assam tea(Camellia sinensis var.assamica)
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作者 Miao-Miao Li Muditha K.Meegahakumbura +5 位作者 Moses C.Wambulwa Kevin S.Burgess Michael Möller Zong-Fang Shen De-Zhu Li Lian-Ming Gao 《Plant Diversity》 SCIE CAS CSCD 2024年第2期229-237,共9页
Chinese Assam tea(Camellia sinensis var.assamica)is an important tea crop with a long history of cultivation in Yunnan,China.Despite its potential value as a genetic resource,its genetic diversity and domestication/br... Chinese Assam tea(Camellia sinensis var.assamica)is an important tea crop with a long history of cultivation in Yunnan,China.Despite its potential value as a genetic resource,its genetic diversity and domestication/breeding history remain unclear.To address this issue,we genotyped 469 ancient tea plant trees representing 26 C.sinensis var.assamica populations,plus two of its wild relatives(six and three populations of C.taliensis and C.crassicolumna,respectively)using 16 nuclear microsatellite loci.Results showed that Chinese Assam tea has a relatively high,but comparatively lower gene diversity(H_(S)=0.638)than the wild relative C.crassicolumna(H_S=0.658).Clustering in STRUCTURE indicated that Chinese Assam tea and its two wild relatives formed distinct genetic groups,with considerable interspecific introgression.The Chinese Assam tea accessions clustered into three gene pools,corresponding well with their geographic distribution.However,New Hybrids analysis indicated that 68.48%of ancient Chinese Assam tea plants from Xishuangbanna were genetic intermediates between the Puer and Lincang gene pools.In addition,10%of the ancient Chinese Assam tea individuals were found to be hybrids between Chinese Assam tea and C.taliensis.Our results suggest that Chinese Assam tea was domesticated separately in three gene pools(Puer,Lincang and Xishuangbanna)in the Mekong River valley and that the hybrids were subsequently selected during the domestication process.Although the domestication history of Chinese Assam tea in southwestern Yunnan remains complex,our results will help to identify valuable genetic resources that may be useful in future tea breeding programs. 展开更多
关键词 Tea plant Hybrid origin Genetic diversity Domestication history Camellia sinensis var.assamica Camellia taliensis
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Nanoparticles for the treatment of spinal cord injury
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作者 Qiwei Yang Di Lu +8 位作者 Jiuping Wu Fuming Liang Huayi Wang Junjie Yang Ganggang Zhang Chen Wang Yanlian Yang Ling Zhu Xinzhi Sun 《Neural Regeneration Research》 SCIE CAS 2025年第6期1665-1680,共16页
Spinal cord injuries lead to significant loss of motor, sensory, and autonomic functions, presenting major challenges in neural regeneration. Achieving effective therapeutic concentrations at injury sites has been a s... Spinal cord injuries lead to significant loss of motor, sensory, and autonomic functions, presenting major challenges in neural regeneration. Achieving effective therapeutic concentrations at injury sites has been a slow process, partly due to the difficulty of delivering drugs effectively. Nanoparticles, with their targeted delivery capabilities, biocompatibility, and enhanced bioavailability over conventional drugs, are garnering attention for spinal cord injury treatment. This review explores the current mechanisms and shortcomings of existing treatments, highlighting the benefits and progress of nanoparticle-based approaches. We detail nanoparticle delivery methods for spinal cord injury, including local and intravenous injections, oral delivery, and biomaterial-assisted implantation, alongside strategies such as drug loading and surface modification. The discussion extends to how nanoparticles aid in reducing oxidative stress, dampening inflammation, fostering neural regeneration, and promoting angiogenesis. We summarize the use of various types of nanoparticles for treating spinal cord injuries, including metallic, polymeric, protein-based, inorganic non-metallic, and lipid nanoparticles. We also discuss the challenges faced, such as biosafety, effectiveness in humans, precise dosage control, standardization of production and characterization, immune responses, and targeted delivery in vivo. Additionally, we explore future directions, such as improving biosafety, standardizing manufacturing and characterization processes, and advancing human trials. Nanoparticles have shown considerable progress in targeted delivery and enhancing treatment efficacy for spinal cord injuries, presenting significant potential for clinical use and drug development. 展开更多
关键词 ANTIOXIDANTS axon regeneration biocompatible materials drug carriers NANOPARTICLES nerve regeneration neuroinflammatory diseases NEUROPROTECTION spinal cord injury stem cells
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Unraveling brain aging through the lens of oral microbiota
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作者 Qinchao Hu Si Wang +2 位作者 Weiqi Zhang Jing Qu Guang-Hui Liu 《Neural Regeneration Research》 SCIE CAS 2025年第7期1930-1943,共14页
The oral cavity is a complex physiological community encompassing a wide range of microorganisms.Dysbiosis of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even... The oral cavity is a complex physiological community encompassing a wide range of microorganisms.Dysbiosis of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even affect systemic health,including brain aging and neurodegenerative diseases.Recent studies have highlighted how oral microbes might be involved in brain aging and neurodegeneration,indicating potential avenues for intervention strategies.In this review,we summarize clinical evidence demonstrating a link between oral microbes/oral infectious diseases and brain aging/neurodegenerative diseases,and dissect potential mechanisms by which oral microbes contribute to brain aging and neurodegeneration.We also highlight advances in therapeutic development grounded in the realm of oral microbes,with the goal of advancing brain health and promoting healthy aging. 展开更多
关键词 Alzheimer's disease brain aging multiple sclerosis NEURODEGENERATION neurodegenerative diseases oral microbiota Parkinson's disease PERIODONTITIS BACTERIA Porphyromonas gingivalis
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Review on“Long-Dan”,one of the traditional Chinese medicinal herbs recorded in Chinese Pharmacopoeia 被引量:22
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作者 Yan-Ming WANG Min XU +3 位作者 Dong WANG Hong-Tao ZHU Chong-Ren YANG Ying-Jun ZHANG 《Natural Products and Bioprospecting》 CAS 2012年第1期1-10,共10页
“Long-Dan”is an important traditional Chinese medicinal(TCM)herb used widely for the treatment of inflammation,hepatitis,rheumatism,cholecystitis,and tuberculosis.In the Chinese Pharmacopoeia,the roots and rhizomes ... “Long-Dan”is an important traditional Chinese medicinal(TCM)herb used widely for the treatment of inflammation,hepatitis,rheumatism,cholecystitis,and tuberculosis.In the Chinese Pharmacopoeia,the roots and rhizomes of four species from the genus Gentiana(Gentianaceae)are recorded as the original materials of“Long-Dan”,called Gentianae Radix et Rhizoma.The species included G.manshurica,G.scabra,G.triflora and G.rigescens,which are distributed in different areas of China.Though iridoid and secoiridoid glucosides were reported as the main constituents in“Long-Dan”,these four different species also resulted in different minor components,which may related to their pharmacological activities.Herein,we summarized the herbal textual study,distribution,chemical constituents,biological investigation and quality control of the recorded“Long-Dan”origins in Chinese Pharmacopoeia during the period 1960 to 2011. 展开更多
关键词 Long-Dan Chinese Pharmacopoeia herbal textual study CHEMISTRY bioactivity quality control
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Response of snow hydrological processes to a changing climate during 1961 to 2016 in the headwater of Irtysh River Basin, Chinese Altai Mountains 被引量:9
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作者 ZHANG Wei KANG Shi-chang +2 位作者 SHEN Yong-ping HE Jian-qiao CHEN An-an 《Journal of Mountain Science》 SCIE CSCD 2017年第11期2295-2310,共16页
With changing climatic conditions and snow cover regime, regional hydrological cycle for a snowy basin will change and further available surface water resources will be redistributed. Assessing snow meltwater effect o... With changing climatic conditions and snow cover regime, regional hydrological cycle for a snowy basin will change and further available surface water resources will be redistributed. Assessing snow meltwater effect on runoff is the key to water safety, under climate warming and fast social-economic developing status. In this study, stable isotopic technology was utilized to analyze the snow meltwater effect on regional hydrological processes, and to declare the response of snow hydrology to climate change and snow cover regime, together with longterm meteorological and hydrological observations, in the headwater of Irtysh River, Chinese Altai Mountains during 1961-2015. The average δ^(18) O values of rainfall, snowfall, meltwater, groundwater and river water for 2014–2015 hydrological year were-10.9‰,-22.3‰,-21.7‰,-15.7‰ and-16.0‰, respectively.The results from stable isotopes, snow melting observation and remote sensing indicated that the meltwater effect on hydrological processes in Kayiertesi River Basin mainly occurred during snowmelt supplying period from April to June. The contribution of meltwater to runoff reached 58.1% during this period, but rainfall, meltwater and groundwater supplied 49.1%, 36.9% and 14.0% of water resource to annual runoff, respectively. With rising air temperature and increasing snowfall in cold season, the snow water equivalent(SWE) had an increasing trend but the snow cover duration declined by about one month including 13-day delay of the first day and 17-day advancement of the end day during 1961–2016. Increase in SWE provided more available water resource. However, variations in snow cover timing had resulted in redistribution of surface water resource, represented by an increase of discharge percentage in April and May, and a decline in Juneand July. This trend of snow hydrology will render a deficit of water resource in June and July when the water resource demand is high for agricultural irrigation and industrial manufacture. 展开更多
关键词 Irtysh River Basin CHINESE AltaiMountains SNOW HYDROLOGY ISOTOPE CLIMATE change
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Interactions of water and nitrogen addition on soil microbial community composition and functional diversity depending on the inter-annual precipitation in a Chinese steppe 被引量:10
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作者 SUN Liang-jie QI Yu-chun +6 位作者 DONG Yun-she HE Ya-ting PENG Qin LIU Xin-chao JIA Jun-qiang GUO Shu-fang CAO Cong-cong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第4期788-799,共12页
Water and nitrogen are primary limiting factors in semiarid grassland ecosystems. Our knowledge is still poor regarding the interactive effects of water and N addition on soil microbial communities, although this info... Water and nitrogen are primary limiting factors in semiarid grassland ecosystems. Our knowledge is still poor regarding the interactive effects of water and N addition on soil microbial communities, although this information is crucial to reveal the mechanisms of the terrestrial ecosystem response to global changes. We addressed this problem by conducting a field experiment with a 15% surplus of the average rainfall under three levels of N addition(50, 100, and 200 kg N ha–1 yr–1) in two consecutive years in Inner Mongolia, China. Microbial community composition and functional diversity were analyzed based on phospholipid fatty acids(PLFA) and BIOLOG techniques, respectively. The results showed that water addition did not affect the soil microbial community composition, but much more yearly precipitation generally decreased the PLFA concentration, which implied a fast response of soil microbes to changes of water condition. Soil fungi was depressed only by N addition at the high level(200 kg N ha–1 yr–1) and without hydrologic leaching, while Gram-negative bacteria was suppressed probably by plant competition at high level N addition but with hydrologic leaching. The study found unilateral positive/negative interactions between water and N addition in affecting soil microbial community, however, climate condition(precipitation) could be a significant factor in disturbing the interactions. This study highlighted that:(1) The sustained effect of pulsed water addition was minimal on the soil microbial community composition but significant on the microbial community functional diversity and(2) the complex interaction between water and N addition on soil microbial community related to the inter-annual variation of the climate and plant response. 展开更多
关键词 water addition nitrogen addition phospholipid fatty acid(PLFA) BIOLOG-substrate utilization semiarid steppe
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A New Method for Quality Control of Chinese Rawinsonde Wind Observations 被引量:10
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作者 LIAO Jie WANG Bin LI Qingxiang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2014年第6期1293-1304,共12页
In 2006,the National Meteorological Information Center (NMIC) of the China Meteorological Administration (CMA) developed its real-time quality control (QC) system of rawinsonde observations coming from the Globa... In 2006,the National Meteorological Information Center (NMIC) of the China Meteorological Administration (CMA) developed its real-time quality control (QC) system of rawinsonde observations coming from the Global Telecommunications System (GTS) and established the Global Upper-air Report Dataset,which,with the NMIC B01 format,is generally referred to as the B01 dataset and updated on a daily basis.However,when the B01 dataset is applied in climate analysis,some wind errors as well as some accurate values with incorrect error marks are found.To improve the quality and usefulness of Chinese rawinsonde wind observations,a new QC method (NewQC) is proposed in this paper.Different from the QC approach used for B01 datasets,the NewQC includes two vertical-wind-shear checks to analyze the vertical consistency of winds,in which the constant height level winds are used as reference data for the QC of mandatory pressure level winds.Different threshold values are adopted in the wind shear checks for different stations and different vertical levels.Several typical examples of QC of different error types by the new algorithm are shown and its performance with respect to 1980-2008 observational data is statistically evaluated.Compared with the radiosonde QC algorithms used in both the Meteorological Assimilation Data Ingest System (MADIS,http://madis.noaa.gov/madis_raob_qc.html) of the National Oceanic and Atmospheric Administration (NOAA) and the B01 dataset,the NewQC shows higher accuracy and better reliability,particularly when used to judge successive observation errors. 展开更多
关键词 quality control rawinsonde observation vertical-wind-shear check
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Stability of soil organic carbon changes in successive rotations of Chinese fir(Cunninghamia lanceolata(Lamb.) Hook) plantations 被引量:7
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作者 ZHANG Jian WANG Silong +1 位作者 FENG Zongwei WANG Qingkui 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第3期352-359,共8页
The importance of soil organic carbon (SOC) under forests in the global carbon cycle depends on the stability of the soil carbon and its availability to soil microbial biomass. We investigated the effects of success... The importance of soil organic carbon (SOC) under forests in the global carbon cycle depends on the stability of the soil carbon and its availability to soil microbial biomass. We investigated the effects of successive rotations of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) plantations on the stability of SOC and its availability to microbes by adopting the two-step hydrolysis with H2SO4 and density fractionation. The results showed that successive rotations of Chinese fir decreased the quantity of total SOC, recalcitrant fraction, and carbohydrates in Labile Pool I (LPI), and microbial properties evidently, especially at 0-10 cm horizon. However, cellulose included in Labile Pool Ⅱ (LP Ⅱ) and the cellulose/total carbohydrates ratio increased in successive rotations of Chinese fir. The noncellulose of carbohydrates included in LPI maybe highly available to soil microbial biomass. Hence the availability of SOC to microbial biomass declined over the successive rotations. Although there was no significant change in recalcitrance of SOC over the successive rotations of Chinese fir, the percentage of heavy fraction to total SOC increased, suggesting that the degree of physical protection for SOC increased and SOC became more stable over the successive rotations. The degradation of SOC quality in successive rotation soils may be attributed to worse environmental conditions resulted from disturbance that related to "slash and burn" site preparation. Being highly correlated with soil microbial properties, the cellulose/total carbohydrates ratio as an effective indicator of changes in availability of SOC to microbial biomass brought by management practices in forest soils. 展开更多
关键词 Chinese fir plantation forest soils organic carbon microbial property biochemical quality density fractionation
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First report of the genus Lysippe Malmgren, 1866 (Polychaeta:Ampharetidae) from Chinese waters 被引量:3
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作者 隋吉星 李新正 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第4期846-849,共4页
The ampharetid genus Lysippe Malmgren, 1866 is reported for the first time from Chinese waters. The identification was based on material deposited in the Marine Biological Museum of the Chinese Academy of Sciences (Qi... The ampharetid genus Lysippe Malmgren, 1866 is reported for the first time from Chinese waters. The identification was based on material deposited in the Marine Biological Museum of the Chinese Academy of Sciences (Qingdao). A new species, Lysippe trichobranchia sp. nov. is described. The new species is widely distributed in shallow waters of the Bohai Gulf, the Yellow Sea and the East China Sea at depths of 10-40 m. 展开更多
关键词 POLYCHAETA Ampharetidae Lysippe trichobranchia new record new species
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Tourism Competitiveness Evaluation and Spatio-temporal Characteristics of Chinese Border Counties 被引量:4
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作者 SHI Yuqing ZHONG Linsheng +1 位作者 CHEN Tian YU Hu 《Chinese Geographical Science》 SCIE CSCD 2016年第6期817-828,共12页
Under the current government strategy of building a Silk Road economic belt, tourism in Chinese border counties has becoming increasingly popular. Studying tourism competitiveness in Chinese border counties is of siza... Under the current government strategy of building a Silk Road economic belt, tourism in Chinese border counties has becoming increasingly popular. Studying tourism competitiveness in Chinese border counties is of sizable theoretical and practical importance, as there are several notable factors involved. In this study, we constructed a tourism competitiveness evaluation model based on eight factors: natural environment, tourism resource, location and transportation, social environment, tourism service facility, border port, tourism industrial cluster and tourism market. We then analyzed the spatial characteristics of tourism competitiveness in border counties and identified five types of border counties: resource advantage type(RA), border-port advantage type(PA), location advantage type(LA), agglomeration advantage type(AA), and relative balance type(RB), and examined the correlation between tourism market competitiveness and interior competitiveness factors in the counties from 2006 to 2011. Results showed that tourism resource, location and transportation, and tourism service facility are the most important competition factors for RA border counties during the study period. Competition factors in PA counties transferred from tourism resource, social environment and tourism service facility to border port and tourism industrial cluster; competition factors in LA counties transferred from natural environment and tourism resource to tourism service facility and tourism industrial cluster and border port. Competition factors in AA counties transferred from tourism service facility to tourism resource. Tourism industrial cluster, tourism service facility and tourism resource proved to be important competition factors in RB counties. The findings of this study can be used to target tourism strategies according to different county types. 展开更多
关键词 border counties tourism competiveness spatio-temporal characteristics type classification
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A Study of Methods to Identify Industry-University-Research Institution Cooperation Partners based on Innovation Chain Theory 被引量:9
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作者 Haiyun Xu Chao Wang +3 位作者 Kun Dong Rui Luo Zenghui Yue Hongshen Pang 《Journal of Data and Information Science》 CSCD 2018年第2期38-61,共24页
Purpose: This study aims at identifying potential industry-university-research collaboration(IURC) partners effectively and analyzes the conditions and dynamics in the IURC process based on innovation chain theory.... Purpose: This study aims at identifying potential industry-university-research collaboration(IURC) partners effectively and analyzes the conditions and dynamics in the IURC process based on innovation chain theory.Design/methodology/approach: The method utilizes multisource data, combining bibliometric and econometrics analyses to capture the core network of the existing collaboration networks and institution competitiveness in the innovation chain. Furthermore, a new identification method is constructed that takes into account the law of scientific research cooperation and economic factors.Findings: Empirical analysis of the genetic engineering vaccine field shows that through the distribution characteristics of creative technologies from different institutions, the analysis based on the innovation chain can identify the more complementary capacities among organizations.Research limitations: In this study, the overall approach is shaped by the theoretical concept of an innovation chain, a linear innovation model with specific types or stages of innovation activities in each phase of the chain, and may, thus, overlook important feedback mechanisms in the innovation process.Practical implications: Industry-university-research institution collaborations are extremely important in promoting the dissemination of innovative knowledge, enhancing the quality of innovation products, and facilitating the transformation of scientific achievements.Originality/value: Compared to previous studies, this study emulates the real conditions of IURC. Thus, the rule of technological innovation can be better revealed, the potential partners of IURC can be identified more readily, and the conclusion has more value. 展开更多
关键词 Institutions collaboration Collaboration network Innovation chain Industrialchain Industry-university-research institutions
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Structure of Chinese City Network as Driven by Technological Knowledge Flows 被引量:32
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作者 MA Haitao FANG Chuanglin +1 位作者 PANG Bo WANG Shaojian 《Chinese Geographical Science》 SCIE CSCD 2015年第4期498-510,共13页
Based on patent cooperation data,this study used a range of city network analysis approaches in order to explore the structure of the Chinese city network which is driven by technological knowledge flows.The results r... Based on patent cooperation data,this study used a range of city network analysis approaches in order to explore the structure of the Chinese city network which is driven by technological knowledge flows.The results revealed the spatial structure,composition structure,hierarchical structure,group structure,and control structure of Chinese city network,as well as its dynamic factors.The major findings are:1) the spatial pattern presents a diamond structure,in which Wuhan is the central city;2) although the invention patent knowledge network is the main part of the broader inter-city innovative cooperation network,it is weaker than the utility model patent;3) as the senior level cities,Beijing,Shanghai and the cities in the Zhujiang(Pearl) River Delta Region show a strong capability of both spreading and controlling technological knowledge;4) whilst a national technology alliance has preliminarily formed,regional alliances have not been adequately established;5) even though the cooperation level amongst weak connection cities is not high,such cities still play an important role in the network as a result of their location within ′structural holes′ in the network;and 6) the major driving forces facilitating inter-city technological cooperation are geographical proximity,hierarchical proximity and technological proximity. 展开更多
关键词 technological knowledge flows patent cooperation city networks network structure structure holes cohesive subgroup
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Application of otolith shape analysis for stock discrimination and species identification of five goby species(Perciformes: Gobiidae) in the northern Chinese coastal waters 被引量:3
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作者 于鑫 曹亮 +3 位作者 刘金虎 赵博 单秀娟 窦硕增 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第5期1060-1073,共14页
We tested the use of otolith shape analysis to discriminate between species and stocks of five goby species( Ctenotrypauchen chinensis, Odontamblyopus lacepedii, Amblychaeturichthys hexanema, Chaeturichthys stigmatias... We tested the use of otolith shape analysis to discriminate between species and stocks of five goby species( Ctenotrypauchen chinensis, Odontamblyopus lacepedii, Amblychaeturichthys hexanema, Chaeturichthys stigmatias, and Acanthogobius hasta) found in northern Chinese coastal waters. The five species were well differentiated with high overall classification success using shape indices(83.7%), elliptic Fourier coefficients(98.6%), or the combination of both methods(94.9%). However, shape analysis alone was only moderately successful at discriminating among the four stocks(Liaodong Bay, LD; Bohai Bay, BH; Huanghe(Yellow) River estuary HRE, and Jiaozhou Bay, JZ stocks) of A. hasta(50%–54%) and C. stigmatias(65.7%–75.8%). For these two species, shape analysis was moderately successful at discriminating the HRE or JZ stocks from other stocks, but failed to effectively identify the LD and BH stocks. A large number of otoliths were misclassified between the HRE and JZ stocks, which are geographically well separated. The classification success for stock discrimination was higher using elliptic Fourier coefficients alone(70.2%) or in combination with shape indices(75.8%) than using only shape indices(65.7%) in C. stigmatias whereas there was little difference among the three methods for A. hasta. Our results supported the common belief that otolith shape analysis is generally more effective for interspecific identification than intraspecific discrimination. Moreover, compared with shape indices analysis, Fourier analysis improves classification success during inter- and intra-species discrimination by otolith shape analysis, although this did not necessarily always occur in all fish species. 展开更多
关键词 GOBIES inter- and intra-specific identification otolith morphology elliptic Fourier analysis shape indices
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Progress of Chinese zooplankton ecology research in Prydz Bay, Antarctica 被引量:5
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作者 LI Chaolun YANG Guang 《Advances in Polar Science》 2017年第2期120-128,共9页
Zooplankton are considered an important trophic link between primary producers and higher trophic level species in the Southern Ocean ecosystem. Since 1989, when the Chinese Antarctic Zhongshan Station was built, zoop... Zooplankton are considered an important trophic link between primary producers and higher trophic level species in the Southern Ocean ecosystem. Since 1989, when the Chinese Antarctic Zhongshan Station was built, zooplankton have regularly been sampled and investigated in Prydz Bay through oceanographic surveys of each Chinese National Antarctic Research Expedition. This review summarizes the main results from zooplankton ecology studies conducted in Prydz Bay by Chinese researchers. Major topics covered in this review are: (1) a description of the biology and ecology of Antarctic krill (Euphausia superba), the key zooplankton species of the Southern Ocean ecosystem; (2) zooplankton community structure, including the horizontal distribution in the epipelagic region and vertical distribution between 0-1500 m; (3) feeding ecology of dominant species such as Antarctic krill, salps and copepods; (4) a short introduction to the molecular research; and (5) prospects for future research. 展开更多
关键词 ZOOPLANKTON Southern Ocean Antarctic krill COMMUNITY feeding ecology Chinese research
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Disordered Translocation is Hastening Local Extinction of the Chinese Giant Salamander 被引量:8
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作者 Guocheng SHU Ping LIU +8 位作者 Tian ZHAO Cheng LI Yinmeng HOU Chunlin ZHAO Jie WANG Xiaoxiao SHU Jiang CHANG Jianping JIANG Feng XIE 《Asian Herpetological Research》 SCIE CSCD 2021年第3期271-279,共9页
Biodiversity is declining globally by an unprecedented extinction rate.This is especially true for amphibians,accounting for 24.3%of all threatened vertebrates.As the largest extant amphibian species in the world,wild... Biodiversity is declining globally by an unprecedented extinction rate.This is especially true for amphibians,accounting for 24.3%of all threatened vertebrates.As the largest extant amphibian species in the world,wild populations of the Chinese giant salamander(Genus Andrias)(CGS)have decreased dramatically because of overexploitation and habitat degradation.Translocation has become an important strategy for restoring threatened wild populations worldwide.However,disordered tra nsloca tion usually has negative effects on the native populations.We provide an overview of CGS translocation and show that disordered translocation can increase local population extinction.Nearly four times the estimated number of wild individuals have been released across China.There a re three types of translocation used for CGS,namely,reinforcement,reintroduction and ecological replacement,the last of which accounts for over one-third of translocations.Our genetic screening revealed that most released individuals were not from local populations,with one to four lineages detected in every release site(n=6).This disordered translocation can potentially reduce the genetic integrity of original populations.Hence,we suggest suspending current CGS translocation activities immediately,until more robust measures can be developed and implemented to improve the current translocation program,especially with respect to lineage identifica tion a nd the identifica tion of appropriate release sites. 展开更多
关键词 Chinese giant salamander genetic test TRANSLOCATION CONSERVATION wild population
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A NOVEL ALGORITHM FOR SIDE PEAKS SUPPRESSION OF AMBIGUITY FUNCTION FOR PASSIVE RADAR BASED ON CHINESE DTTB SIGNAL 被引量:5
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作者 Li Jichuan Lu Xiaode Zhao Yaodong 《Journal of Electronics(China)》 2012年第6期485-492,共8页
The ambiguity function of Chinese standard Digital Television Terrestrial Broadcasting (DTTB) signals for passive radar contains one main peak and many side peaks. The side peaks may cause the false alarms. The relati... The ambiguity function of Chinese standard Digital Television Terrestrial Broadcasting (DTTB) signals for passive radar contains one main peak and many side peaks. The side peaks may cause the false alarms. The relative positions and the reasons for the side peaks are analyzed and a new algorithm for side peaks suppression is proposed in this paper. The algorithm, in consideration of the characteristics of the structure of the frame, can eliminate the side peaks completely in the valid Doppler observation interval by setting the reference signals to zero at equal intervals. Both the simulative and experimental results show that this algorithm can improve the performance of target detection of the passive radar based on DTTB signal. 展开更多
关键词 Passive radar Digital Television Terrestrial Broadcasting (DTTB) Ambiguity Function (AF) Side peaks suppression
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