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Effect of dietary supplementation with discardednutrient medium of Cordyceps militaris on layingperformance and diversity of intestinal flora in laying hens
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作者 XU Fangxu ZHANG Jinying +2 位作者 LI Bingxin LIU Yefei WANG Ze 《沈阳师范大学学报(自然科学版)》 CAS 2024年第2期186-192,共7页
The aim of the experiment was to explore the feasibility of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 100 g/kg, 200 g/kg, 300 g/kg of discarded nutrient medium of Cordy... The aim of the experiment was to explore the feasibility of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 100 g/kg, 200 g/kg, 300 g/kg of discarded nutrient medium of Cordyceps militaris were added to the basal diet of laying hens. The results showed that the optimal addition of discarded nutrient medium of Cordyceps militaris in the diet of laying hens was 10%. According to the results of measuring the conventional indicators of eggs, the weight of eggs produced by laying hens fed with discarded nutrient medium of Cordyceps militaris was higher than that of laying hens fed with ordinary laying hens. The content of interleukin-1(IL-1) in the experimental group was significantly higher than that in the control group, and the concentration of IL-1 increased by 141.5 pg/mL, which indicated that the application of discarded nutrient medium of Cordyceps militaris effectively improved the immunity of laying hens. The high-throughput analysis of the intestinal contents of the two groups of laying hens showed that the microbial population abundance of the intestinal tract of the experimental group was greater than that of control group, and the application of discarded nutrient medium of Cordyceps militaris increased the diversity of bacteria in the intestinal tract of laying hens. In addition, the sensitivity of some pathogenic bacteria in the intestinal tract of chickens to drugs was also increased, thereby reducing the use of antibiotics. The secondary utilization of discarded nutrient medium of Cordyceps militaris has great development and utilization prospects, which provided a scientific reference and basic theoretical basis for the development of discarded nutrient medium of Cordyceps militaris as feed in the production of laying hens. 展开更多
关键词 Cordyceps militaris discarded nutrient medium drug susceptibility intestinal flora laying hens
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论高校体育教师现代信息素质的培养 被引量:11
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作者 汤君才 《体育文化导刊》 北大核心 2003年第1期49-51,共3页
关键词 高校 体育教师 信息素质 现状 信息意识 信息能力 信息道德
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我国大众体育产业的现状及发展趋向 被引量:7
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作者 赵忠伟 《体育文化导刊》 北大核心 2003年第2期8-9,共2页
关键词 中国 体育产业 产业结构 现状 发展趋向 体育场馆 体育文化 消费主体 体育资产
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法、中教师专业能力标准比较研究 被引量:2
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作者 陈莹 孙河川 郑弘 《辽宁教育》 2014年第10期9-12,共4页
2013年7月1日最新出台的法国教师专业能力标准提出了教师必须具备的14项专业能力。本文就法、中两国最新的教师专业能力标准的一级指标进行比较,对两国的相通之处和各自关注的重点予以探讨。通过对比发现,法国的教师能力标准体现了危机... 2013年7月1日最新出台的法国教师专业能力标准提出了教师必须具备的14项专业能力。本文就法、中两国最新的教师专业能力标准的一级指标进行比较,对两国的相通之处和各自关注的重点予以探讨。通过对比发现,法国的教师能力标准体现了危机意识与学习意识,更加注重教师专业能力,突出了学生的主体地位,强调了教师语言能力和掌握信息与通讯技术的重要性。 展开更多
关键词 专业标准 专业能力标准 教师评价 法国
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一道高考语文试题的命题疏漏
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作者 谷孝龙 《语文知识》 2002年第3期46-46,9,共2页
2001年普通高等学校招生全国统一考试语文试题第一题第25题是这样命题的: 把下面的长句改成较短的句子,使意思表达得更为清楚。(不得改变原意,可以添加必要的词语)(2分) 现在许多国家都已经能够生产可以独立操作机床,可以在病房细心照... 2001年普通高等学校招生全国统一考试语文试题第一题第25题是这样命题的: 把下面的长句改成较短的句子,使意思表达得更为清楚。(不得改变原意,可以添加必要的词语)(2分) 现在许多国家都已经能够生产可以独立操作机床,可以在病房细心照料病人,可以在危险区域进行作业的机器人。高考《语文试题参考答案及评分标准》是这样定的: 展开更多
关键词 高考 2001年 语文试题 命题
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Structure, synthesis, and catalytic properties of nanosize cerium-zirconium-based solid solutions in environmental catalysis 被引量:20
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作者 Jixing Liu Zhen Zhao +1 位作者 Chunming Xu Jian Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第10期1438-1487,共50页
Nanosize cerium-zirconium solid solution(CZO)with a special fluorite structure has received an increasing research interest due to their remarkable advantages such as excellent oxygen storage capacity and great flexib... Nanosize cerium-zirconium solid solution(CZO)with a special fluorite structure has received an increasing research interest due to their remarkable advantages such as excellent oxygen storage capacity and great flexibility in their composition and structure.By partial metal(including rare earth,transition,alkaline earth or other metal)doping into CZO,the physicochemical properties of these catalytic materials can be controllable adjusted for the study of specific reactions.To date,nanosize CZO has been prepared by co-precipitation,sol-gel,surfactant-assisted approach,solution combustion,micro-emulsion,high energy mechanical milling,etc.The advent of these methodologies has prompted researchers to construct well-defined networks with customized micromorphology and functionalities.In this review,we describe not only the basic structure and synthetic strategies of CZO,but also their relevant applications in environmental catalysis,such as the purification for CO,nitrogen oxides(NOx),volatile organic compounds(VOC),soot,hydrocarbon(HC),CO2 and solid particulate matters(PM),and some reaction mechanisms are also summarized. 展开更多
关键词 Cerium-zirconium solid solution SYNTHESIS Method STRUCTURE Environmental catalysis
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Analysis of Grain Storage Security Countermeasures under the New Normal Condition with "Grain Storage Technology" as the Core 被引量:6
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作者 Xingang ZHAO Shengzhong DONG +3 位作者 Hongwei MA Zhaohuan WEN Xiufeng SHAN Peng MAO 《Agricultural Science & Technology》 CAS 2017年第10期1971-1974,共4页
Grain storage security is big issue related to national economy and the people's livelihood, as well as one of the most important strategic requirements in China. Under the background of grain supply-side structural ... Grain storage security is big issue related to national economy and the people's livelihood, as well as one of the most important strategic requirements in China. Under the background of grain supply-side structural reform, this paper analyzed the grain storage security countermeasures under the new normal conditions with "grain storage technology", one of the national grain security strategies of China during the 13th Five-year Plan, as the guiding ideology, from the perspectives of scientific technologies, policy supports, government supports and talent construction, so as to provide supports for the storage enterprises with vulnerable technological links. In addition, the food security issues discussed in this paper could be a helping hand in improving people's living quality, enhancing grain storage ecological quality, promoting grain green storage quality security, and be of important and profound strategic significance to enhance the macro-control capability of the government, maintain social stability and people's health. 展开更多
关键词 Grain storage technology Grain storage security Countermeasure analysis
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Electronic interaction between single Pt atom and vacancies on boron nitride nanosheets and its influence on the catalytic performance in the direct dehydrogenation of propane 被引量:7
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作者 Xiaoying Sun Meijun Liu +2 位作者 Yaoyao Huang Bo Li Zhen Zhao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第6期819-825,共7页
The electronic metal-support interaction(EMSI)is one of most intriguing phenomena in heterogeneous catalysis.In this work,this subtle effect is clearly demonstrated by density functional theory(DFT)calculations of sin... The electronic metal-support interaction(EMSI)is one of most intriguing phenomena in heterogeneous catalysis.In this work,this subtle effect is clearly demonstrated by density functional theory(DFT)calculations of single Pt atom supported on vacancies in a boron nitride nanosheet.Moreover,the relation between the EMSI and the performance of Pt in propane direct dehydrogenation(PDH)is investigated in detail.The charge state and partial density of states of single Pt atom show distinct features at different anchoring positions,such as boron and nitrogen vacancies(Bvac and Nvac,respectively).Single Pt atom become positively and negatively charged on Bvac and Nvac,respectively.Therefore,the electronic structure of Pt can be adjusted by rational deposition on the support.Moreover,Pt atoms in different charge states have been shown to have different catalytic abilities in PDH.The DFT calculations reveal that Pt atoms on Bvac(Pt-Bvac)have much higher reactivity towards reactant/product adsorption and C–H bond activation than Pt supported on Nvac(Pt-Nvac),with larger adsorption energy and lower barrier along the reaction pathway.However,the high reactivity of Pt-Bvac also hinders propene desorption,which could lead to unwanted deep dehydrogenation.Therefore,the results obtained herein suggest that a balanced reactivity for C–H activation in propane and propene desorption is required to achieve optimum yields.Based on this descriptor,a single Pt atom on a nitrogen vacancy is considered an effective catalyst for PDH.Furthermore,the deep dehydrogenation of the formed propene is significantly suppressed,owing to the large barrier on Pt-Nvac.The current work demonstrates that the catalytic properties of supported single Pt atoms can be tuned by rationally depositing them on a boron nitride nanosheet and highlights the great potential of single-atom catalysis in the PDH reaction. 展开更多
关键词 PROPANE Direct dehydrogenation Platinum Boron nitride Single atom catalysis Density functional theory Electronic metel-support interaction
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Three-dimensionally ordered macroporous CeO_2/Al_2O_3-supported Au nanoparticle catalysts: Effects of CeO_2 nanolayers on catalytic activity in soot oxidation 被引量:5
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作者 Baofang Jin Yuechang Wei +5 位作者 Zhen Zhao Jian Liu Yazhao Li Renjie Li Aijun Duan Guiyuan Jiang 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第9期1629-1641,共13页
A series of catalysts consisting of three‐dimensionally ordered macroporous(3DOM)x‐CeO2/Al2O3‐supported Au nanoparticles(x=2,10,20,and40wt%)were successfully synthesized using a reduction‐deposition method.These c... A series of catalysts consisting of three‐dimensionally ordered macroporous(3DOM)x‐CeO2/Al2O3‐supported Au nanoparticles(x=2,10,20,and40wt%)were successfully synthesized using a reduction‐deposition method.These catalysts were characterized using scanning electron microscopy,the Brunauer‐Emmett‐Teller method,X‐ray diffraction,transmission electron microscopy,ultraviolet‐visible spectroscopy,and temperature‐programmed reduction by H2.Au nanoparticles of mean particle size5nm were well dispersed and supported on the inner walls of uniform macropores.The3DOM structure improved the contact efficiency between soot and the catalyst.An Al‐Ce‐O solid solution was formed in the multilayer support,i.e.,x‐CeO2/Al2O3,by the incorporation of Al3+ions into the CeO2lattice,which resulted in the creation of extrinsic oxygen vacancies.Strong interactions between the metal(Au)and the support(Ce)increased the amount of active oxygen species,and this promoted soot oxidation.The catalytic performance in soot combustion was evaluated using a temperature‐programmed oxidation technique.The presence of CeO2nanolayers in the3DOM Au/x‐CeO2/Al2O3catalysts clearly improved the catalytic activities in soot oxidation.Among the prepared catalysts,3DOM Au/20%CeO2/Al2O3showed high catalytic activity and stability in diesel soot oxidation. 展开更多
关键词 Three‐dimensionally ordered macroporous material Gold nanoparticle Multilayer support CeO2 nanolayer Soot combustion
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试论朱自清的写作教学观 被引量:2
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作者 梁秋实 《语文教学之友》 2007年第1期34-36,共3页
关键词 写作教学 教学观 朱自清
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Photocatalytic performance of TiO_2 nanocrystals with/without oxygen defects 被引量:12
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作者 Shu-yuan Liu Kezhen Qi Meng Qiu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第4期867-875,共9页
To investigate the role of oxygen defects on the photocatalytic activity of TiO2,the TiO2 nanocrystals with/without oxygen defects are successfully synthesized by the hydrothermal and sol‐gel methods,respectively.The... To investigate the role of oxygen defects on the photocatalytic activity of TiO2,the TiO2 nanocrystals with/without oxygen defects are successfully synthesized by the hydrothermal and sol‐gel methods,respectively.The as‐prepared TiO2 nanocrystals with defects are light blue and the absorption edge of light is towards the visible light region(~420 nm).Raman and X‐ray photoelectron spectroscopy(XPS)measurements all confirm that the concentration of oxygen vacancies in the TiO2 synthesized by the sol‐gel method is less than that synthesized through the hydrothermal route.The introduction of oxygen defects contributes to a new state in the band gap that narrows the band gap,which is the reason for the extension of light absorption into the visible light region.The photocurrent results confirm that this band‐gap narrowing enhances the photocurrent response under simulated solar light irradiation.The TiO2 with oxygen defects shows a higher photocatalytic activity for decomposition of a methylene blue solution compared with that of the perfect TiO2 sample.The photocatalytic mechanism is discussed based on the density functional theory calculations and photoluminescence spectroscopy measurements. 展开更多
关键词 TIO2 DEFECT Optical property Photocatalytic activity Density functional theory calculation
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A review on TiO_2-based Z-scheme photocatalysts 被引量:40
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作者 Kezhen Qi Bei Cheng Jiaguo Yu 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第12期1936-1955,共20页
TiO2‐based Z‐scheme photocatalysts have attracted considerable attention because of the low recombination rate of their photogenerated electron–hole pairs and their high photocatalytic efficiency.In this review,the... TiO2‐based Z‐scheme photocatalysts have attracted considerable attention because of the low recombination rate of their photogenerated electron–hole pairs and their high photocatalytic efficiency.In this review,the reaction mechanism of Z‐scheme photocatalysts,recent research progress in the application of TiO2‐based Z‐scheme photocatalysts,and improved methods for photocatalytic performance enhancement are explored.Their applications,including water splitting,CO2reduction,decomposition of volatile organic compounds,and degradation of organic pollutants,are also described.The main factors affecting the photocatalytic performance of TiO2‐based Z‐scheme photocatalysts,such as pH,conductive medium,cocatalyst,architecture,and mass ratio,are discussed.Concluding remarks are presented,and some suggestions for the future development of TiO2‐based Z‐scheme photocatalysts are highlighted. 展开更多
关键词 TIO2 Z‐scheme photocatalyst Water splitting CO2 reduction Pollutant degradation
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Photocatalytic H2 generation via CoP quantum-dot-modified g-C3N4 synthesized by electroless plating 被引量:11
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作者 Kezhen Qi Wenxiu Lv +1 位作者 Iltaf Khan Shu-yuan Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第1期114-121,共8页
Photocatalytic water splitting is a promising method for hydrogen production.Numerous efficient photocatalysts have been synthesized and utilized.However,photocatalysts without a noble metal as the co-catalyst have be... Photocatalytic water splitting is a promising method for hydrogen production.Numerous efficient photocatalysts have been synthesized and utilized.However,photocatalysts without a noble metal as the co-catalyst have been rarely reported.Herein,a CoP co-catalyst-modified graphitic-C3N4(g-C3N4/CoP)is investigated for photocatalytic water splitting to produce H2.The g-C3N4/CoP composite is synthesized in two steps.The first step is related to thermal decomposition,and the second step involves an electroless plating technique.The photocatalytic activity for hydrogen evolution reactions of g-C3N4 is distinctly increased by loading the appropriate amount of CoP quantum dots(QDs).Among the as-synthesized samples,the optimized one(g-C3N4/CoP-4%)shows exceptional photocatalytic activity as compared with pristine g-C3N4,generating H2 at a rate of 936μmol g^-1 h^-1,even higher than that of g-C3N4 with 4 wt%Pt(665μmol g^-1 h^-1).The UV-visible and optical absorption behavior confirms that g-C3N4 has an absorption edge at 451 nm,but after being composited with CoP,g-C3N4/CoP-4%has an absorption edge at 497 nm.Furthermore,photoluminescence and photocurrent measurements confirm that loading CoP QDs to pristine g-C3N4 not only enhances the charge separation,but also improves the transfer of photogenerated e--h+pairs,thus improving the photocatalytic performance of the catalyst to generate H2.This work demonstrates a feasible strategy for the synthesis of highly efficient metal phosphide-loaded g-C3N4 for hydrogen generation. 展开更多
关键词 Photocatalysis CoP quantum dots Electroless plating H2 generation g-C3N4
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Corrosion behavior of bulk two-phase Ag-25Cu alloys with different microstructures in NaCl aqueous solution
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作者 Zhong-qiu CAO Xiao-tong YIN +4 位作者 Zhong-qiu JIA Qiu-yue TIAN Jie LU Ke ZHANG Yan WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第7期1495-1502,共8页
In order to have a better understanding on the corrosion mechanisms of bulk two-phase Ag-25Cu (at.%) alloys with different microstructures, two bulk nanocrystalline Ag-25Cu alloys and one coarse grained counterpart we... In order to have a better understanding on the corrosion mechanisms of bulk two-phase Ag-25Cu (at.%) alloys with different microstructures, two bulk nanocrystalline Ag-25Cu alloys and one coarse grained counterpart were prepared by liquid phase reduction (LPR), mechanical alloying (MA) and powder metallurgy (PM) methods, respectively. Their corrosion behavior was investigated comparatively using electrochemical methods in NaCl aqueous solution. Results show that the microstructure of the coarse grained PMAg-25Cu alloy is extremely inhomogeneous. On the contrary, compared with PMAg-25Cu alloy, the microstructures of the nanocrystalline LPRAg-25Cu and MAAg-25Cu alloys are more homogeneous, especially for LPRAg-25Cu alloy. The corrosion rate of MAAg-25Cu alloy is higher than that of PMAg-25Cu alloy, but lower than that of LPRAg-25Cu alloy. Furthermore, the passive films formed by three Ag-25Cu alloys exhibit n-type semiconducting properties. The passive current density of LPRAg-25Cu alloy is lower than that of PMAg-25Cu alloy, but higher that of MAAg-25Cu alloy. 展开更多
关键词 nanocrystalline Ag-Cu bulk alloy mechanical alloying liquid phase reduction microstructure electrochemical corrosion
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One new species of Clemelis Robineau-Desvoidy(Diptera: Tachinidae) from China
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作者 Bo HAO Chuntian ZHANG 《Entomotaxonomia》 CSCD 2019年第3期233-237,共5页
One new species of the genus Clemelis from Baishanzu,Zhejiang province,Oriental China is described and illustrated,namely Clemelis jingentaoi Zhang&Hao sp.nov.This species is similar to Palaearctic C.pullata(Meige... One new species of the genus Clemelis from Baishanzu,Zhejiang province,Oriental China is described and illustrated,namely Clemelis jingentaoi Zhang&Hao sp.nov.This species is similar to Palaearctic C.pullata(Meigen)in appearance,but differs from the latter as follows:occiput without black setae at below postocellar setae,mid tibia with 4–6 anterodorsal setae,syntergite 1+2 with 2 strong median marginal setae and surstyli short. 展开更多
关键词 CALYPTRATAE Goniini TAXONOMY
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视唱练耳训练之我见 被引量:1
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作者 沈建国 《艺海》 2007年第5期74-,共1页
  视唱练耳是艺术院校中技术性很强的一门专业基础课.视唱练耳英语称为Sight-Simging and Eartrain,起源于十九世纪的欧洲.……
关键词 视唱练耳 和声音程 旋律音程
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One new species,two newly recorded genera and four newly recorded species of Tachinidae(Diptera)from Liaoning,China
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作者 Yizhuo ZHANG Bo HAO Chuntian ZHANG 《Entomotaxonomia》 CSCD 2020年第2期122-129,共8页
Tachinid specimens(Diptera:Tachinidae)from Mt.Huangyi of Kuandian,Eastern Liaoning,China were examined.One species is described as new to science,Linnaemya(s.str.)flavifemur Zhang sp.nov.,with photos of adults and mal... Tachinid specimens(Diptera:Tachinidae)from Mt.Huangyi of Kuandian,Eastern Liaoning,China were examined.One species is described as new to science,Linnaemya(s.str.)flavifemur Zhang sp.nov.,with photos of adults and male terminalia.Two genera and four species are newly recorded from China:Microsoma Macquart,1855,Rhacodinella Mesnil,1968;Melastrongygaster atrata Shima,2015,Microsoma exigua(Meigen,1824),Rhacodinella aurata Mesnil,1970 and Smidtia fukushii Shima,1996;and their diagnosis and photos are provided. 展开更多
关键词 CALYPTRATAE tachinid fly taxonomy Kuandian
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Descriptions of four new species of Helina Robineau-Desvoidy(Diptera: Muscidae) from Yunnan, China
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作者 Shuai WANG Wanqi XUE Jing DU 《Entomotaxonomia》 CSCD 2022年第4期250-259,共10页
Four new species of Helina Robineau-Desvoidy from Yunnan, China are reported: H.paratacticispina sp. nov., H. yilaensis sp. nov., H. similisipedana sp. nov., and H. yutengi sp. nov.
关键词 CALYPTRATAE MUSCOIDEA description taxonomy
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One new species of Everestiomyia Townsend(Diptera:Tachinidae)from western China
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作者 Bo HAO Hongying HU +1 位作者 Junjian LI Chuntian ZHANG 《Entomotaxonomia》 CSCD 2021年第1期32-37,共6页
Everestiomyia Townsend,1933(Diptera:Tachinidae)belongs to the tribe Ernestiini in the Tachininae.One new species of this genus from the Altun Mountains of Xinjiang,western China was found and is described:Everestiomyi... Everestiomyia Townsend,1933(Diptera:Tachinidae)belongs to the tribe Ernestiini in the Tachininae.One new species of this genus from the Altun Mountains of Xinjiang,western China was found and is described:Everestiomyia nudioculata Zhang sp.nov. 展开更多
关键词 CALYPTRATAE Tachininae Ernestiini TAXONOMY
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A new species of the genus Opalimosina Rohá?ek(Diptera: Sphaeroceridae) from Liaoning, Northeast China
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作者 Jinliang DENG Lixin SU Jie XU 《Entomotaxonomia》 CSCD 2019年第4期281-285,共5页
This paper describes and illustrates a new species of Opalimosina Rohacek from Liaoning, Northeast China, namely Opalimosina(Opalimosina) verruca sp. nov., and provides a distribution map and a key to Chinese Opalimos... This paper describes and illustrates a new species of Opalimosina Rohacek from Liaoning, Northeast China, namely Opalimosina(Opalimosina) verruca sp. nov., and provides a distribution map and a key to Chinese Opalimosina. The genus Opalimosina is a new record for Liaoning, Northeast China. 展开更多
关键词 Acalyptratae small dungflies taxonomy key
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