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An Asymmetric Galactic Stellar Disk Traced by OB-type Stars from LAMOST DR7
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作者 Xiaopeng Liu Hao Tian +4 位作者 Wenyuan Cui Linlin Li Jiaming Liu Zhenyan Huo Yawei Gao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期38-51,共14页
Using 9943 OB-type stars from LAMOST DR7 in the solar neighborhood,we fit the vertical stellar density profile with the model including a single exponential distribution at different positions(R,Φ).The distributions ... Using 9943 OB-type stars from LAMOST DR7 in the solar neighborhood,we fit the vertical stellar density profile with the model including a single exponential distribution at different positions(R,Φ).The distributions of the scale heights and scale length show that the young disk traced by the OB-type stars is not axisymmetric.The scale length decreases versus the azimuthal angleΦ,i.e.,from.■kpc withΦ=-3°to■kpc withΦ=9°.Meanwhile we find signal of non-symmetry in the distribution of the scale height of the north and south of the disk plane.The scale height in the north side shows signal of flaring of the disk,while that of the south disk stays almost constant around h_(s)=130 pc.The distribution of the displaceeent of the disk plane Z_(0)also shows variance versus the azimuthal angleΦ,which displays significant differences with the warp model constrained by the Cepheid stars.We also test different values for the position of the Sun,and the distance between the Sun and the Galactic center affects the scale heights and the displacement of the disk significantly,but that does not change our conclusion that the disk is not axisymmetric. 展开更多
关键词 Galaxy:disk galaxies:spiral stars:early-type stars:massive
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CAUCHY TYPE INTEGRALS AND A BOUNDARY VALUE PROBLEM IN A COMPLEX CLIFFORD ANALYSIS
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作者 曹南斌 李尊凤 +1 位作者 杨贺菊 乔玉英 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期369-385,共17页
Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quan... Clifford analysis is an important branch of modern analysis;it has a very important theoretical significance and application value,and its conclusions can be applied to the Maxwell equation,Yang-Mill field theory,quantum mechanics and value problems.In this paper,we first give the definition of a quasi-Cauchy type integral in complex Clifford analysis,and get the Plemelj formula for it.Second,we discuss the H?lder continuity for the Cauchy-type integral operators with values in a complex Clifford algebra.Finally,we prove the existence of solutions for a class of linear boundary value problems and give the integral representation for the solution. 展开更多
关键词 Clifford analysis Cauchy type integral Plemelj formula Holder continuous boundary value problems
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Stability Analysis of a Class of Nonlinear Fractional Differential Systems With Riemann-Liouville Derivative
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作者 Ruoxun Zhang Shiping Yang Shiwen Feng 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第8期1883-1885,共3页
Dear Editor,This letter investigates the stability of n-dimensional nonlinear fractional differential systems with Riemann-Liouville derivative.By using the Mittag-Leffler function,Laplace transform and the Gronwall-B... Dear Editor,This letter investigates the stability of n-dimensional nonlinear fractional differential systems with Riemann-Liouville derivative.By using the Mittag-Leffler function,Laplace transform and the Gronwall-Bellman lemma,one sufficient condition is attained for the asymptotical stability of a class of nonlinear fractional differential systems whose order lies in(0,2).According to this theory,if the nonlinear term satisfies some conditions,then the stability condition for nonlinear fractional differential systems is the same as the ones for corresponding linear systems.Two examples are provided to illustrate the applications of our result. 展开更多
关键词 LIOUVILLE RIEMANN NONLINEAR
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Improved simulation of winter wheat yield in North China Plain by using PRYM-Wheat integrated dry matter distribution coefficient
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作者 Xuan Li Shaowen Wang +6 位作者 Yifan Chen Danwen Zhang Shanshan Yang Jingwen Wang Jiahua Zhang Yun Bai Sha Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1381-1392,共12页
The accurate simulation of regional-scale winter wheat yield is important for national food security and the balance of grain supply and demand in China.Presently,most remote sensing process models use the“biomass... The accurate simulation of regional-scale winter wheat yield is important for national food security and the balance of grain supply and demand in China.Presently,most remote sensing process models use the“biomass×harvest index(HI)”method to simulate regional-scale winter wheat yield.However,spatiotemporal differences in HI contribute to inaccuracies in yield simulation at the regional scale.Time-series dry matter partition coefficients(Fr)can dynamically reflect the dry matter partition of winter wheat.In this study,Fr equations were fitted for each organ of winter wheat using site-scale data.These equations were then coupled into a process-based and remote sensingdriven crop yield model for wheat(PRYM-Wheat)to improve the regional simulation of winter wheat yield over the North China Plain(NCP).The improved PRYM-Wheat model integrated with the fitted Fr equations(PRYM-Wheat-Fr)was validated using data obtained from provincial yearbooks.A 3-year(2000-2002)averaged validation showed that PRYM-Wheat-Fr had a higher coefficient of determination(R^(2)=0.55)and lower root mean square error(RMSE=0.94 t ha^(-1))than PRYM-Wheat with a stable HI(abbreviated as PRYM-Wheat-HI),which had R^(2) and RMSE values of 0.30 and 1.62 t ha^(-1),respectively.The PRYM-Wheat-Fr model also performed better than PRYM-Wheat-HI for simulating yield in verification years(2013-2015).In conclusion,the PRYM-Wheat-Fr model exhibited a better accuracy than the original PRYM-Wheat model,making it a useful tool for the simulation of regional winter wheat yield. 展开更多
关键词 dry matter partition remote sensing model winter wheat yield North China Plain
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The Influence Mechanism of an Inclusive Organizational Climate on Innovation Input of Sci-Tech Talents
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作者 Yang Xiaoyi Zhao Weihong Ma Xiaomeng 《Contemporary Social Sciences》 2024年第2期52-66,共15页
With the implementation of China’s innovation-driven development strategy,the competition among sci-tech talents has become increasingly fierce.Stimulating the innovative vigor of sci-tech talents has become a hot to... With the implementation of China’s innovation-driven development strategy,the competition among sci-tech talents has become increasingly fierce.Stimulating the innovative vigor of sci-tech talents has become a hot topic in theoretical research and policy practice.Based on the data from 246 questionnaires collected from sci-tech talents in Hebei province,this study explored the influence mechanism of an inclusive organizational climate on innovation input from technological talents and verified the mediating effects of innovation self-efficacy and intrinsic motivation.The results indicate that an inclusive organizational climate has a significant positive impact on innovation input,innovation self-efficacy,and intrinsic motivation of sci-tech talents.Both innovation self-efficacy and intrinsic motivation play a partial mediating role between an inclusive climate and innovation input.This study verified the important role of an inclusive climate in an organization’s human resource management practices and encouraged managers to emphasize enhancing the innovation self-efficacy and intrinsic motivation of sci-tech talents,thereby continuously improving the level of innovation. 展开更多
关键词 inclusive climate innovation self-efficacy intrinsic motivation sci-tech talents
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Temporal and Spectral Characteristics of Persistent Emission and Special Bursts of Magnetar SGR J1935+2154 Based on Insight-HXMT
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作者 Xue-Feng Lu Li-Ming Song +7 位作者 Ming-Yu Ge Shuang-Nan Zhang Jin-Lu Qu Ce Cai Cong-Zhan Liu Cheng-Kui Li Yu-Cong Fu Ying-Chen Xu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期225-233,共9页
In October 2022,the magnetar SGR J1935+2154 entered the active outburst state.During the episode,the InsightHXMT satellite carried out a long observation that lasted for 20 days.More than 300 bursts were detected,and ... In October 2022,the magnetar SGR J1935+2154 entered the active outburst state.During the episode,the InsightHXMT satellite carried out a long observation that lasted for 20 days.More than 300 bursts were detected,and a certain amount of persistent radiation signals were also accumulated.This paper mainly introduces the results of persistent radiation profile folding and period search based on Insight-HXMT data.At the same time,the burst phase distribution characteristics,spectral lag results of burst,the spectral characteristics of zero-lag bursts and the time-resolved spectral evolution characteristics of high-flux bursts are reported.We found that there is no significant delay feature during different energy bands for the bursts of SGR J1935+2154.The observed zero-lag burst does not have a unique spectrum.The time-resolved spectrum of the individual burst has consistent spectral types and spectral parameters at different time periods of the burst.We also find that the burst number phase distribution and the burst photon phase distribution have the same tendency to concentrate in specific regions of the persistent emission profile. 展开更多
关键词 radiation mechanisms:general dense matter magnetic fields
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Study on the Photosynthetic Characteristics of Six Varieties(Strains)in Chinese Chestnut
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作者 Lizhi FU Yong YANG +6 位作者 Xiaoxiao KANG Meng WANG Jing LIU Xuan WANG Dongsheng WANG Liyang YU Hai’e ZHANG 《Agricultural Biotechnology》 2024年第1期9-14,57,共7页
[Objectives]This study was conducted to investigate the differences of photosynthetic physiological characteristics of different varieties(strains),which will provide a theoretical basis for high photosynthesis effici... [Objectives]This study was conducted to investigate the differences of photosynthetic physiological characteristics of different varieties(strains),which will provide a theoretical basis for high photosynthesis efficiency breeding and application in Chinese chestnut.[Methods]Six Chinese chestnut varieties of Castanea mollissima‘Yanbao’,C.mollissima‘Yanqiu’,C.mollissima‘Yanchang’,C.mollissima‘Yanjia’,C.mollissima‘Qianxi 37’,and C.mollissima‘Hybrid 22’were used as the materials.Using the portable photosynthesis system Li-6400,we measured the photosynthetic characteristics and diurnal variation of leaf samples of six different chestnut varieties or strains.We fitted the light response curves and photosynthetic parameters using the leaf floating model.Additionally,we determined the chlorophyll content in the leaves using a UV-visible spectrophotometer.[Results]Among the six chestnut varieties or strains,‘Yanqiu’exhibited a significantly higher photosynthetic light saturation point(P LSP)compared to other five varieties,and‘Hybrid 22’ranked second,indicating that these two varieties had the strongest adaptation to high light intensity.The photosynthetic light compensation point(P LCP)of‘Yanchang’was significantly higher than other five varieties,and"Qianxi 37"ranked second,indicating that these two varieties had the strongest adaptation to low light intensity.Additionally,they exhibited higher chlorophyll content and maintained good photosynthetic characteristics even in shaded environments with weak light stress.Varieties‘Yanbao’and‘Yanjia’showed higher P LSP and lower P LCP,indicating that these two varieties have a wider range of adaptation to light intensity.They were capable of efficiently utilizing light across a broader spectrum of intensities.‘Yanqiu’had the highest maximum net photosynthetic rate(P n,max)and the lowest dark respiration rate(R d),along with the highest chlorophyll content.It indicated that‘Yanqiu’has strong photosynthetic capacity and organic matter accumulation ability.It also had the highest P LSP,enabling it to fully utilize the high light environment of the Yanshan Mountains and possessed high light efficiency characteristics.The P n,max of‘Yanqiu’was significantly higher than other varieties.‘Hybrid 22’and‘Yanbao’also exhibited significantly higher P n,max compared with‘Yanjia’and‘Qianxi 37’.‘Yanchang’had the lowest P n,max.The order of P n,max among the six chestnut varieties or strains was as follows:‘Yanqiu’>‘Hybrid 22’>‘Yanbao’>‘Yanjia’>‘Qianxi 37’>‘Yanchang’.[Conclusions] 展开更多
关键词 Chinese chestnut Diurnal variation of photosynthesis Light response model Light response curve CHLOROPHYLL
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Effects of Different Climates and Soil Environments in the Yanshan Production Area on the Growth and Quality of Chestnuts
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作者 Jiaqing WU Haie ZHANG Jingzheng ZHANG 《Agricultural Biotechnology》 2024年第2期81-87,共7页
[Objectives] This study conducted investigations on the climate and soil nutrients of different chestnut orchards in the Yanshan region, selected key ecological factors affecting the growth and fruit quality of chestn... [Objectives] This study conducted investigations on the climate and soil nutrients of different chestnut orchards in the Yanshan region, selected key ecological factors affecting the growth and fruit quality of chestnuts, and provided a theoretical basis for the cultivation, introduction, and scientific planting of high-quality chestnuts. [Methods] The ‘Yanshanzaofeng’ chestnuts in four orchards located in Qianxi, Qianan, Funing, and Qinglong of Hebei Science and Technology Normal University were selected. The climate and soil nutrient conditions of the four orchards were investigated. Growth indicators such as branch length and diameter, nut weight, and internal quality indicators such as starch, fat, and protein content were analyzed. Principal component analysis was conducted on nine climate factors and twelve soil factors in the four chestnut orchards to identify the most closely related ecological factors influencing chestnut growth and quality. [Results] (i) Different orchards had varying climate conditions, with Qianan orchard having higher rainfall than the others, Funing orchard having the highest number of sunshine hours in the growing season, and Qinglong orchard experiencing the greatest temperature difference during the growing season. (ii) Significant differences were found in soil nutrient content among the orchards, with the coefficient of variation for organic matter and mineral elements ranging from 19.1% (S) to 80.3% (available phosphorus). (iii) The main ecological factor influencing chestnut growth was the photosynthetic factor, while fruit quality was influenced by a combination of climatic factors, photosynthetic factors, and nutrient factors. Key ecological factor indicators included: annual precipitation, annual sunshine hours, growing season precipitation, growing season sunshine hours, soil organic matter, available phosphorus, available potassium, alkali nitrogen, copper, zinc, available boron, and sulfur. Soluble solids were significantly positively correlated with growing season sunshine hours, and fat was significantly positively correlated with available potassium and alkali nitrogen, and significantly positively correlated with available phosphorus. [Conclusions] Orchards with high growing season precipitation, long sunshine hours, and high organic matter and nitrogen-phosphorus-potassium content in the soil are more conducive to promoting the growth of ‘Yanshanzaofeng’ chestnuts and improving fruit quality. 展开更多
关键词 CHESTNUT Ecological factors Fruit quality Principal component analysis
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The Clumpy Structure of Five Star-bursting Dwarf Galaxies in the MaNGA Survey
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作者 Mengting Ju Jun Yin +6 位作者 Lei Hao Chenxu Liu Chao-Wei Tsai Junfeng Wang Zhengyi Shao Shuai Feng Yu Rong 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期83-103,共21页
The star-forming clumps in star-bursting dwarf galaxies provide valuable insights into understanding the evolution of dwarf galaxies.In this paper,we focus on five star-bursting dwarf galaxies featuring off-centered c... The star-forming clumps in star-bursting dwarf galaxies provide valuable insights into understanding the evolution of dwarf galaxies.In this paper,we focus on five star-bursting dwarf galaxies featuring off-centered clumps in the Mapping Nearby Galaxies at Apache Point Observatory survey.Using the stellar population synthesis software Fitting Analysis using Differential evolution Optimization,we obtain the spatially resolved distribution of the star formation history,which allows us to construct the g-band images of the five galaxies at different ages.These images can help us to probe the evolution of the morphological structures of these galaxies.While images of a stellar population older than 1 Gyr are typically smooth,images of a stellar population younger than 1 Gyr reveal significant clumps,including multiple clumps which appear at different locations and even different ages.To study the evolutionary connections of these five galaxies to other dwarf galaxies before their star-forming clumps appear,we construct the images of the stellar populations older than three age nodes,and define them to be the images of the"host"galaxies.We find that the properties such as the central surface brightness and the effective radii of the hosts of the five galaxies are in between those of dwarf ellipticals(dEs)and dwarf irregulars(dIrrs),with two clearly more similar to dEs and one more similar to dIrrs.Among the five galaxies,8257-3704 is particularly interesting,as it shows a previous starburst event that is not quite visible from its gri image,but only visible from images of the stellar population at a few hundred million years.The star-forming clump associated with this event may have appeared at around 600 Myr ago and disappeared at around 40 Myr ago. 展开更多
关键词 GALAXIES dwarf-galaxies evolution-galaxies formation-Galaxy STRUCTURE
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Corrigendum to“GmTOC1b negatively regulates resistance to Soybean mosaic virus”.[Crop J.11(2023)1762-1773]
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作者 Yuhang Zhang Haiping Du +7 位作者 Tiantian Zhao Chunmei Liao Tu Feng Jun Qin Baohui Liu Fanjiang Kong Zhijun Che Liyu Chen 《The Crop Journal》 SCIE CSCD 2024年第1期320-320,共1页
The authors regret to report a mistake in the text and an associated change necessary to section 3.6 of the paper.On page 1766 in the right-hand column,line 4,the heading of subsection 3.6“GmWRKY40 represses the expr... The authors regret to report a mistake in the text and an associated change necessary to section 3.6 of the paper.On page 1766 in the right-hand column,line 4,the heading of subsection 3.6“GmWRKY40 represses the expression of PR genes”should be changed to“GmWRKY40 promotes the expression of PR genes”.The authors would like to apologize for any inconvenience caused. 展开更多
关键词 COR HEADING RESISTANCE
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A Lightweight IoT Malware Detection and Family Classification Method
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作者 Changguang Wang Ziqi Ma +2 位作者 Qingru Li Dongmei Zhao Fangwei Wang 《Journal of Computer and Communications》 2024年第4期201-227,共27页
A lightweight malware detection and family classification system for the Internet of Things (IoT) was designed to solve the difficulty of deploying defense models caused by the limited computing and storage resources ... A lightweight malware detection and family classification system for the Internet of Things (IoT) was designed to solve the difficulty of deploying defense models caused by the limited computing and storage resources of IoT devices. By training complex models with IoT software gray-scale images and utilizing the gradient-weighted class-activated mapping technique, the system can identify key codes that influence model decisions. This allows for the reconstruction of gray-scale images to train a lightweight model called LMDNet for malware detection. Additionally, the multi-teacher knowledge distillation method is employed to train KD-LMDNet, which focuses on classifying malware families. The results indicate that the model’s identification speed surpasses that of traditional methods by 23.68%. Moreover, the accuracy achieved on the Malimg dataset for family classification is an impressive 99.07%. Furthermore, with a model size of only 0.45M, it appears to be well-suited for the IoT environment. By training complex models using IoT software gray-scale images and utilizing the gradient-weighted class-activated mapping technique, the system can identify key codes that influence model decisions. This allows for the reconstruction of gray-scale images to train a lightweight model called LMDNet for malware detection. Thus, the presented approach can address the challenges associated with malware detection and family classification in IoT devices. 展开更多
关键词 IoT Security Visual Explanations Multi-Teacher Knowledge Distillation Lightweight CNN
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Vegetation NPP Distribution Based on MODIS Data and CASA Model——A Case Study of Northern Hebei Province 被引量:19
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作者 YUAN Jinguo NIU Zheng WANG Chenli 《Chinese Geographical Science》 SCIE CSCD 2006年第4期334-341,共8页
Net Primary Productivity (NPP) is one of the important biophysical variables of vegetation activity, and it plays an important role in studying global carbon cycle, carbon source and sink of ecosystem, and spatial and... Net Primary Productivity (NPP) is one of the important biophysical variables of vegetation activity, and it plays an important role in studying global carbon cycle, carbon source and sink of ecosystem, and spatial and temporal distri- bution of CO2. Remote sensing can provide broad view quickly, timely and multi-temporally, which makes it an attractive and powerful tool for studying ecosystem primary productivity, at scales ranging from local to global. This paper aims to use Moderate Resolution Imaging Spectroradiometer (MODIS) data to estimate and analyze spatial and temporal dis- tribution of NPP of the northern Hebei Province in 2001 based on Carnegie-Ames-Stanford Approach (CASA) model. The spatial distribution of Absorbed Photosynthetically Active Radiation (APAR) of vegetation and light use efficiency in three geographical subregions, that is, Bashang Plateau Region, Basin Region in the northwestern Hebei Province and Yanshan Mountainous Region in the Northern Hebei Province were analyzed, and total NPP spatial distribution of the study area in 2001 was discussed. Based on 16-day MODIS Fraction of Photosynthetically Active Radiation absorbed by vegetation (FPAR) product, 16-day composite NPP dynamics were calculated using CASA model; the seasonal dy- namics of vegetation NPP in three subregions were also analyzed. Result reveals that the total NPP of the study area in 2001 was 25.1877×106gC/(m2·a), and NPP in 2001 ranged from 2 to 608gC/(m2·a), with an average of 337.516gC/(m2·a). NPP of the study area in 2001 accumulated mainly from May to September (DOY 129–272), high NPP values appeared from June to August (DOY 177–204), and the maximum NPP appeared from late July to mid-August (DOY 209–224). 展开更多
关键词 河北北部 植被 净初级生产力 NPP MODIS数据 CASA模型 遥感
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The Investigation of Main Pathogens Causing Dairy Cattle Recessive Mastitis in Eastern Hebei 被引量:1
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作者 GAO Gui-sheng GAO Guang-ping +4 位作者 LI Zheng-ben SHI Qiu-mei ZHANG Yan-ying SHAO Xin-hua LIANG Yin-ju 《Animal Husbandry and Feed Science》 CAS 2013年第4期198-200,共3页
[Objective]This paper aimed to determine the main pathogens causing dairy cattle recessive mastitis in eastern Hebei and provide certain reference for local veterinarians and cow farmers to prevent and cure the diseas... [Objective]This paper aimed to determine the main pathogens causing dairy cattle recessive mastitis in eastern Hebei and provide certain reference for local veterinarians and cow farmers to prevent and cure the disease.[Method]512 cows from 5 different farms in eastern Hebei were selected,and LMT,milk ph test and somatic cell direct counting methods were combined and used to conduct recessive mastitis' s epidemiological investigation,as well as isolate and identify the pethogens.[Result]The results indicated that the incidence of recessive mastitis is 60.7%(311 / 512),bacteria isolation rate reached 87.8%(273 /311).Total 81 isolates,belonging to 3 classes and 5 types were identified in milk samples of positive milk area from 273 cows with recessive mastitis.Among which,19 isolates were Streptococcus,accounting for 23.45%.Staphylococcus had 31 isolates,accounting for 38.27%.Enterobacter had 3,accounting for 3.7%.Other unshaped had 28 isolates,accounting for 34.6%.[Conclusion] The main pathogens caused dairy cattle recessive mastitis in eastern Hebei were Streptococcus agalactiae and Staphylococcus aureus. 展开更多
关键词 Dairy cattle Recessive mastitis Pathogen
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Resonant Andreev reflection in a normal-metal/quantum-dot/superconductor system with coupled Majorana bound states
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作者 王素新 李玉现 刘建军 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第3期351-356,共6页
Andreev reflection (AR) in a normal-metal/quantum-dot/superconductor (N-QD-S) system with coupled Majorana bound states (MBSs) is investigated theoretically. We find that in the N--QD-S system, the AR can be enh... Andreev reflection (AR) in a normal-metal/quantum-dot/superconductor (N-QD-S) system with coupled Majorana bound states (MBSs) is investigated theoretically. We find that in the N--QD-S system, the AR can be enhanced when coupling to the MBSs is incorporated. Fano line-shapes can be observed in the AR conductance spectrum when there is an appropriate QD-MBS coupling or MBS-MBS coupling. The AR conductance is always e2/2h at the zero Fermi energy point when only QD--MBSs coupling is considered. In addition, the resonant AR occurs when the MBS-MBS coupling roughly equals to the QD energy level. We also find that an AR antiresonance appears when the QD energy level approximately equals to the sum of the QD-MBS coupling and the MBS-MBS coupling. These features may serve as characteristic signatures for the probe of MBSs. 展开更多
关键词 Majorana bound states Andreev reflection Fano effect quantum dot
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The Genetic Types of Baiyun Cave in Lincheng County of Hebei Province
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作者 Yanping SUN Jian WANG +2 位作者 Xiaoman ZHANG Qianhua ZHENG Huafang HUANG 《Asian Agricultural Research》 2013年第10期72-76,共5页
Baiyun Karst Caverns in Lincheng County,Hebei Province,is a rare karst caverns in subhumid climate region of the north.It was developed in carbonatite strata,particularly in Zhangxia formation of the Middle Cambrain s... Baiyun Karst Caverns in Lincheng County,Hebei Province,is a rare karst caverns in subhumid climate region of the north.It was developed in carbonatite strata,particularly in Zhangxia formation of the Middle Cambrain series.Erosion-corrosion landscape and chemical deposition landscape are abundant,They are various shapes,curtain drapery,cave flag,cave shield,stalactite,stalagmite,cave flowers,botryoid,soda straw are developed,especially heligmite,soda straw,cave flowers are the most characteristic. 展开更多
关键词 Baiyun CAVE in Lincheng COUNTY LANDSCAPE GENETIC t
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Formation of Baiyun Karst Cave Landscapes in the Kongshan Mountain of Lincheng County, Hebei Province
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作者 WANG Jian ZHANG Xiaoman +2 位作者 SUN Yanping ZHENG Qianhua HUANG Huafang 《Journal of Landscape Research》 2013年第Z2期33-39,共7页
Baiyun Cave in the Kongshan Mountain is a cave which developed mostly in thick-layer oolitic limestone of the Middle Cambrain Zhangxia Formation in the Quaternary period.The spatial distribution of the karst cave was ... Baiyun Cave in the Kongshan Mountain is a cave which developed mostly in thick-layer oolitic limestone of the Middle Cambrain Zhangxia Formation in the Quaternary period.The spatial distribution of the karst cave was cotrolled by the NNW,NE and near-EW faults.The karst cave system consists of three layers,includes mainly hall type and corridor type,within which there are diversified sedimentary landscapes and corrosion landscapes,especially"Reticular helictite","Jade-hairpin pointing at bottle","Yin and yang jade columns"and many other special landscapes can hardly be found in other karst caves.Influenced by the strong tectonic activities since the Quaternary period,the cave collapsed several times,and landscapes within the cave have been seriously damaged.Study on the landscape formation of karst caves and influence of cave environment changes on its landscape development will contribute to the reasonable development and protection of tourist resources in the cave. 展开更多
关键词 Baiyun CAVE KARST CAVE landscapes CAUSE Formation and evolution
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Agricultural Drought Resisting and Hydrological-Ecological Changes Taking Hebei Province in North China as an Example
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作者 Yanrui Shang Kaijun Sun +1 位作者 Haifeng Shen Gongying Liu 《Journal of Environmental Science and Engineering(A)》 2013年第3期189-196,共8页
关键词 水文生态系统 农业抗旱 河北省 中国北方 生态变化 干旱风险 农业系统 土地利用强度
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Humidifying Effect of Riparian Wetland Park of Shijiazhuang, Hebei Province in Autumn
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作者 ZHANG Zhaoqi WANG Hongjuan +1 位作者 YANG Man HUANG Huafang 《Journal of Landscape Research》 2015年第6期63-68,共6页
As an important part of urban green space system, wetland parks have good ecological environment and various landscape resources, which play an irreplaceable role in adjusting the climate, beautifying the environment ... As an important part of urban green space system, wetland parks have good ecological environment and various landscape resources, which play an irreplaceable role in adjusting the climate, beautifying the environment and maintaining regional ecological balance. Therefore, research on humidifying effect of wetland park is of great significance. Air humidity below the height of 1.5 m above various underlying surfaces was measured in Taiping Riparian Wetland Park of Shijiazhuang. Monitoring time was selected in October 10–12, 2012 and six days among September and October, 2013 which were sunny days without wind(or the speed of wind less than 0.2 m/s). By analyzing the basic distribution regularity of humidity from horizontal and vertical directions at different times in autumn days, humidifying effect of various types of plants could be summarized from the sampled data. The humidifying effect of arbor-grasses can strengthen with the increase of temperature. The humidifying effect is the strongest at 10:00–14:00, then, it weakens after noon and the reduction rate tends to be smaller. Second, the humidity above the height of 0.2 m changes at a small scale and is much lower than that close to ground, which reveals great effect of ground cover plants and soil moisture. According to the monitoring data below the height of 1.5 m, the humidifying effect of shrubs is stronger than that of arbor-grasses. Last, the humidifying effect of surfaces with different land covers from strong to weak are shrubs, arbor-grasses, river. The rational allocation on various types of wetlands with a wide variety of structures can improve the atmospheric environment more effectively. 展开更多
关键词 Taiping Riparian Wetland Park Arbor-grasses SHRUBS Humidifying effect
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Biodiversity Sustainability Assessment of Principal Ecosystems in Hebei,China
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作者 WANG Hongmei QIAN Jinping +1 位作者 ZHANG Xiulan HE Xiubin 《Wuhan University Journal of Natural Sciences》 CAS 2007年第4期749-754,共6页
Aiming at providing theoretical basis for effective protection of biodiversity, the study presents a cascade method which combines both qualitative and quantitative methods, incorporates basic data with RS(remote se... Aiming at providing theoretical basis for effective protection of biodiversity, the study presents a cascade method which combines both qualitative and quantitative methods, incorporates basic data with RS(remote sense) technology, and ranks the ecosystems according to its ability of biodiversity sustainability in Hebei Province. The results indicate that the most important areas for protection in Hebei Province are forest and meadow ecosystems in some highlands around Xiaowutai Mountain, Wuling Mountain, North Hebei, Taihang Mountain and East Hebei; grass ecosystems in part of plateau area and North Hebei; and some scattered wetlands in the plain and inshore areas. This method is suitable for undertaking large-scale investigations especially when the data are not adequate or unevenly distributed spatially. 展开更多
关键词 biodiversity sustainability ASSESSMENT cascade method ECOSYSTEM
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The Application of Information Technology in Open Calculus Teaching of TV University
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作者 ShuLi WEI Zhaokun XUAN 《International Journal of Technology Management》 2015年第5期102-104,共3页
关键词 微积分教学 远程教学 信息技术 传统教学方法 多媒体技术 应用 电大 多媒体教学
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