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“以用定学”提高英语师范专业教学实效性
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作者 马玉杰 《广东蚕业》 2018年第7期50-51,共2页
英语师范专业的教学对于提升学生应用技能水平起到了至关重要的作用,因此,怎样提升其教学实效性是当前师范英语教师应该重点关注的问题。文章从英语师范专业教学在应用技能培养方面存在的不足谈起,分析了英语师范专业教学实效性不强的... 英语师范专业的教学对于提升学生应用技能水平起到了至关重要的作用,因此,怎样提升其教学实效性是当前师范英语教师应该重点关注的问题。文章从英语师范专业教学在应用技能培养方面存在的不足谈起,分析了英语师范专业教学实效性不强的基本原因,在此基础上,提出了"以用定学"的教学方案,并探讨了几点提高英语师范专业教学实效性的策略。 展开更多
关键词 以用定学 英语师范专业 教学 实效性
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A high entropy stabilized perovskite oxide La_(0.2)Pr_(0.2)Sm_(0.2)Gd_(0.2)Sr_(0.2)Co_(0.8)Fe_(0.2)O_(3−δ)as a promising air electrode for reversible solid oxide cells
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作者 LI Ruoyu LI Xiaoyu +2 位作者 ZHANG Jinke GAO Yuan LING Yihan 《燃料化学学报(中英文)》 北大核心 2025年第2期282-290,共9页
Reversible solid oxide cell(RSOC)is a new energy conversion device with significant applications,especially for power grid peaking shaving.However,the reversible conversion process of power generation/energy storage p... Reversible solid oxide cell(RSOC)is a new energy conversion device with significant applications,especially for power grid peaking shaving.However,the reversible conversion process of power generation/energy storage poses challenges for the performance and stability of air electrodes.In this work,a novel high-entropy perovskite oxide La_(0.2)Pr_(0.2)Gd_(0.2)Sm_(0.2)Sr_(0.2)Co_(0.8)Fe_(0.2)O_(3−δ)(HE-LSCF)is proposed and investigated as an air electrode in RSOC.The electrochemical behavior of HE-LSCF was studied as an air electrode in both fuel cell and electrolysis modes.The polarization impedance(Rp)of the HE-LSCF electrode is only 0.25Ω·cm^(2) at 800℃ in an air atmosphere.Notably,at an electrolytic voltage of 2 V and a temperature of 800℃,the current density reaches up to 1.68 A/cm^(2).The HE-LSCF air electrode exhibited excellent reversibility and stability,and its electrochemical performance remains stable after 100 h of reversible operation.With these advantages,HE-LSCF is shown to be an excellent air electrode for RSOC. 展开更多
关键词 reversible solid oxide cell high entropy stabilized perovskite air electrode electrochemical performance
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新农人培育的价值意蕴、现实困境及优化路径 被引量:1
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作者 蔡善文 《农业科技管理》 2024年第3期79-84,共6页
新农人现已成为农业农村现代化进程中引领新农民、开发新农业、建设新农村的一支生力军,是破解农业现代化进程中人才瓶颈难题的重要路径之一。在界定新农人内涵特征和厘清新农人价值意蕴的基础上,通过现实调研和实地走访等方式,了解到... 新农人现已成为农业农村现代化进程中引领新农民、开发新农业、建设新农村的一支生力军,是破解农业现代化进程中人才瓶颈难题的重要路径之一。在界定新农人内涵特征和厘清新农人价值意蕴的基础上,通过现实调研和实地走访等方式,了解到新农人培育面临培育帮扶措施不完善、培育实施环节不精准、培育保障机制不健全等现实困境。鉴于此,在新农人培育过程中,提出了构建人才良性发展机制、建立分层分类培训体系和健全培育保障机制等优化培育新农人的实践路径。 展开更多
关键词 新农人 价值内涵 农业农村现代化 按需定学
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Preparation and Characterization of ZnO-CuO-Bi_(2)O_(3)-B_(2)O_(3)-SiO_(2)System Low Melting Sealing Glasses 被引量:1
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作者 HE Yifeng LI Xiuying +5 位作者 LI Chaoyuan GUO Huiming XIAO Zhuohao ZHU Shengbin DONG Hongbo FU Zhen 《陶瓷学报》 CAS 北大核心 2024年第5期931-940,共10页
Lead-free low melting glasses,ZnO-CuO-Bi_(2)O_(3)-B_(2)O_(3)-SiO_(2)system,with fixed contents of 15 mol%CuO and 20 mol%Bi_(2)O_(3),were prepared by using melt cooling method.Structure and thermal properties of the gl... Lead-free low melting glasses,ZnO-CuO-Bi_(2)O_(3)-B_(2)O_(3)-SiO_(2)system,with fixed contents of 15 mol%CuO and 20 mol%Bi_(2)O_(3),were prepared by using melt cooling method.Structure and thermal properties of the glasses were studied by using X-ray diffractometer(XRD),infrared spectrometer(FIT-IR),thermal dilatometer and differential thermal analyzer(DTA).Chemical durability of the glasses was studied by using dissolution rate method.Wettability of glasses on substrate was tested by using button sintering experiment.It is found that alkaline resistance of the glass solders is lower than that of plate glass and the water resistance is comparable with that of plate glass.The sealing temperatures are Ts=445-490℃,while the average thermal expansion coefficient from room temperature to 300℃is in the range of(65-82)×10^(−7)℃^(−1).At sealing temperature,the glass solders have good wettability on plate glass or alumina substrate.They are not crystallized even sintered at the sealing temperature for 30 min.The solder glasses are suitable for sealing plate glass,alumina and other inorganic non-metallic materials. 展开更多
关键词 bismuth borate glass solder glasses WETTABILITY chemical durability thermal properties
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对高职语文课程转型的思考与实践 被引量:18
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作者 王燕 《中国成人教育》 北大核心 2010年第1期155-156,共2页
近年来,随着高等职业教育的不断发展,高职语文教学受到了较大冲击。如何正确定位高职语文教育,如何成功转型高职语文课程,是每一个高职语文教师迫切需要思考的问题。本文旨在寻找探索高职语文教学的新途径,并为日后的研究提供一定的借鉴。
关键词 就业导向 协同教学 以用定学 能力本位
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Acoustic location echo signal extraction of buried non-metallic pipelines based on EMD and wavelet threshold joint denoising
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作者 GE Liang YUAN Xuefeng +2 位作者 XIAO Xiaoting LUO Ping WANG Tian 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第4期417-431,共15页
In the acoustic detection process of buried non-metallic pipelines,the echo signal is often interfered by a large amount of noise,which makes it extremely difficult to effectively extract useful signals.An denoising a... In the acoustic detection process of buried non-metallic pipelines,the echo signal is often interfered by a large amount of noise,which makes it extremely difficult to effectively extract useful signals.An denoising algorithm based on empirical mode decomposition(EMD)and wavelet thresholding was proposed.This method fully considered the nonlinear and non-stationary characteristics of the echo signal,making the denoising effect more significant.Its feasibility and effectiveness were verified through numerical simulation.When the input SNR(SNRin)is between-10 dB and 10 dB,the output SNR(SNRout)of the combined denoising algorithm increases by 12.0%-34.1%compared to the wavelet thresholding method and by 19.60%-56.8%compared to the EMD denoising method.Additionally,the RMSE of the combined denoising algorithm decreases by 18.1%-48.0%compared to the wavelet thresholding method and by 22.1%-48.8%compared to the EMD denoising method.These results indicated that this joint denoising algorithm could not only effectively reduce noise interference,but also significantly improve the positioning accuracy of acoustic detection.The research results could provide technical support for denoising the echo signals of buried non-metallic pipelines,which was conducive to improving the acoustic detection and positioning accuracy of underground non-metallic pipelines. 展开更多
关键词 buried non-metallic pipeline acoustic positioning signal processing optimal decomposition scale wavelet basis function EMD combined wavelet threshold algorithm
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千古先贤一圣心——胡居仁兴复白鹿洞书院浅析
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作者 罗才成 《福建论坛(社科教育版)》 2009年第12期67-68,共2页
以一介布衣获聘入主千年学府江西白鹿洞书院的明初理学大儒胡居仁,延名师、购书籍、量学租、陈学弊、作洞记、定学规,拳拳兴复白鹿洞书院于将废。虽因学风士习等原因导致他最终忍痛辞归,但给书院留下了宝贵的精神遗产,对整饬当时浮风士... 以一介布衣获聘入主千年学府江西白鹿洞书院的明初理学大儒胡居仁,延名师、购书籍、量学租、陈学弊、作洞记、定学规,拳拳兴复白鹿洞书院于将废。虽因学风士习等原因导致他最终忍痛辞归,但给书院留下了宝贵的精神遗产,对整饬当时浮风士习、传播程朱理学思想有着深远的历史影响。 展开更多
关键词 胡居仁 延名师 定学 白鹿洞书院
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Enhancing Na^(+) diffusion dynamics and structural stability of O3-NaMn_(0.5)Ni_(0.5)O_(2)cathode by Sc and Zn dual-substitution
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作者 Bin-bin WANG Yi-ming FENG +8 位作者 Xin LUO Qun HUANG Zi-xing HOU Ya-qin WU Peng-yu WANG Yu-yang QI Qing-fei MENG Wei-feng WEI Liang-jun ZHOU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第10期3344-3357,共14页
Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural ... Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural stability of NaMN was investigated.The physicochemical characterizations suggest that the introduction of Sc and Zn broaden Na^(+) diffusion channels and weaken the Na—O bonds,thereby facilitating the diffusion of sodium ions.Simulations indicate that the Sc and Zn dual-substitution decreases the diffusion barrier of Na-ions and improves the conductivity of the material.The dual-substituted NaMn_(0.5)Ni_(0.4)Sc_(0.04)Zn_(0.04)O_(2)(Na MNSZ44)cathode delivers impressive cycle stability with capacity retention of 71.2%after 200 cycles at 1C and 54.8%after 400 cycles at 5C.Additionally,the full cell paired with hard carbon anode exhibits a remarkable long-term cycling stability,showing capacity retention of 64.1%after 250 cycles at 1C.These results demonstrate that Sc and Zn dual-substitution is an effective strategy to improve the Na^(+) diffusion dynamics and structural stability of NaMN. 展开更多
关键词 layered oxide cathode Sc and Zn dual-substitution structural stability Na^(+)diffusion dynamics
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Strength and plasticity improvement induced by strong grain refinement after Zr alloying in selective laser-melted AlSiMg1.4 alloy 被引量:1
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作者 Yao-xiang GENG Chun-feng ZAI +3 位作者 Jiang YU Hao TANG Hong-wei LÜ Zhi-jie ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2733-2742,共10页
In order to enhance the mechanical properties of the selective laser-melted(SLM) high-Mg content AlSiMg1.4 alloy,the Zr element was introduced.The influence of Zr alloying on the processability,microstructure,and mech... In order to enhance the mechanical properties of the selective laser-melted(SLM) high-Mg content AlSiMg1.4 alloy,the Zr element was introduced.The influence of Zr alloying on the processability,microstructure,and mechanical properties of the alloy was systematically investigated through performing microstructure analysis and tensile testing.It was demonstrated that the SLM-fabricated AlSiMg1.4-Zr alloy exhibited high process stability with a relative density of over 99.5% at various process parameters.Besides,the strong grain refinement induced by the primary Al3Zr particle during the melt solidification process simultaneously enhanced both the strength and plasticity of the alloy.The values for the yield strength,ultimate tensile strength,and elongation of the SLM-fabricated AlSiMg1.4-Zr were(343±3) MPa,(485±4) MPa,and(10.2±0.2)%,respectively,demonstrating good strengthplasticity synergy in comparison to the AlSiMg1.4 and other Al-Si-based alloys fabricated by SLM. 展开更多
关键词 selective laser melting process stability grain refinement microstructure mechanical properties
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Evaluation of a Novel 32 X-STR Loci Multiplex System in the Forensic Application
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作者 ZHANG Juntao YANG Xingyi +5 位作者 YU Zhengliang ZHAO Peng LIU Dayu HAN Xiaolong SUN Hongyu LIU Chao 《刑事技术》 2024年第5期456-463,共8页
The AGCU X Plus STR system is a newly developed multiplex PCR kit that detects 32 X-chromosomal STR loci simultaneously.These are DXS6807,DXS9895,linkage group 1(DXS10148,DXS10135,DXS8378),DXS9902,DXS6795,DXS6810,DXS1... The AGCU X Plus STR system is a newly developed multiplex PCR kit that detects 32 X-chromosomal STR loci simultaneously.These are DXS6807,DXS9895,linkage group 1(DXS10148,DXS10135,DXS8378),DXS9902,DXS6795,DXS6810,DXS10159,DXS10162,DXS10164,DXS7132,linkage group 2(DXS10079,DXS10074,DXS10075),DXS981,DXS6800,DXS6803,DXS6809,DXS6789,DXS7424,DXS101,DXS7133,GATA172D05,GATA165B12,linkage group 3(DXS10103,HPRTB,DXS10101),GATA31E08 and linkage group 4(DXS8377,DXS10134,DXS7423).A major advantage of this kit is that it takes into account linkage between loci,in addition to detecting more X-STR loci.In order to evaluate the forensic application of 32 X-STR fl uorescence amplifi cation system,PCR settings,sensitivity,species specifi city,stability,DNA mixtures,concordance,stutter,sizing precision,and population genetics investigation were evaluated according to the Scientific Working Group on DNA Analysis Methods(SWGDAM)developmental validation guidelines.The study showed that the genotyping results of each locus were signifi cantly accurate when the DNA template was at least 62.5 pg.Complete profi les were obtained for the 1∶1 and 1∶3 combinations.A total of 209 unrelated individuals from Southern Chinese Han community,consisting of 84 females and 125 males,were selected for population studies,and 285 allele profi les were detected from 32 X-STR loci.The polymorphism information content(PIC)ranged from 0.2721 in DXS6800,to 0.9105 in DXS10135,with an average of 0.6798.DXS10135(PIC=0.9105)was the most polymorphic locus,with discrimination power(DP)of 0.9164 and 0.9871 for the male and female.The cumulative PD_(F),PD_(M),MEC_(trio) and MEC_(duo) valu es were all greater than 0.999999999.There were 78 different DXS10103-HPRTB-DXS10101 haplotypes among the 125 males,and the haplotype diversity was 0.9810.There was no signifi cant difference in the cumulative PD_(F),PD_(M),MEC_(trio) and MEC_(duo) values whether considering linkage or not.In summary,the new X-STR multiplex typing system is effective and reliable,which can be useful in human genetic analysis and kinship testing as a potent complement to autosomal STR typing. 展开更多
关键词 forensic genetics X-STR loci kinship analysis EVALUATION
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Research Progress of Bactrocera dorsalis and Its Species Complex 被引量:3
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作者 刘建宏 熊小真 +2 位作者 潘涌智 杨丽英 黎小军 《Agricultural Science & Technology》 CAS 2011年第11期1657-1661,共5页
Research progress of B. dorsalis and its species complex in Taiwan region and abroad was summarized from the aspects of classification, origin, transmission, distribution, host, biological characteristics and adaptabi... Research progress of B. dorsalis and its species complex in Taiwan region and abroad was summarized from the aspects of classification, origin, transmission, distribution, host, biological characteristics and adaptability to environmental conditions, in order to provide references and basis for researching B. dorsalis and its species complex in China. 展开更多
关键词 B. dorsalis Species complex IDENTIFICATION Biological characteristics
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Mathematical Definitions of Operators for Cartographic Generalization 被引量:2
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作者 王晓妮 张洁 《Geo-Spatial Information Science》 2003年第1期70-73,共4页
This paper puts forword 11 cartographic generalization operator models and introduces their mathematical definitions,and thus a precise mathematical form and quantitative description has been given to these formerly l... This paper puts forword 11 cartographic generalization operator models and introduces their mathematical definitions,and thus a precise mathematical form and quantitative description has been given to these formerly limited qualitative concepts.The meaning of mathematical definition of operators for cartographic generalization and the application prospect in computer_aided cartography (CAC) is stated.ract The Jurassic strata in Jingyan of Sichuan containing the Mamenchinsaurus fauna are dealt with and divided in this paper. The Mamenchisaurus fossils contained there are compared in morphological features and stratigraphically with other types of the genus on by one. The comprehensive analysis show that the Mamenchisaurus fauna of Jingyan appeared in the early Late Jurassic and is primitive in morphology. The results of the morphological identification and stratigraphical study agree with each other. Their evolutionary processes in different apoches of the Late Jurassic also made clear. Key words Jingyan, Sichuan, Mamenchisaurus Fauna, stratigraphy, evolution 展开更多
关键词 operators for cartographic generalization mathematical definition SELECTION SIMPLIFICATION STRESS
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Ultracytochemical Localization of Acid Phosphatase in Nucellar Cells of Wheat During Degeneration 被引量:6
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作者 田国伟 申家恒 尤瑞麟 《Acta Botanica Sinica》 CSCD 1999年第8期791-794,共4页
The distribution of acid phosphatase activity in nucellar cells of wheat ( Triticum aestivum L.) during degeneration has been studied using the lead precipitation method at the electron microscopic level. Acid phos... The distribution of acid phosphatase activity in nucellar cells of wheat ( Triticum aestivum L.) during degeneration has been studied using the lead precipitation method at the electron microscopic level. Acid phosphatase was localized in the slightly condensed nuclear chromatin in nucellar cells without any sign of ultrastructural degeneration. As the nucellar cells started degenerating, the enzyme activity in the cell was observed, in the order from small vacuoles to cell walls, mitochondria, plastids and endoplasmic reticulum. Enzyme activity was the highest in most components of the nucellar cells adjacent to the embryo sac where the degeneration of nucellar cells was the strongest, but it was not observed in the nuclei of the degenerated nucellar cells. The results indicated that the degeneration of nucellar cells was a progressive and orderly process and supported that the degeneration of nucellar cells was a programmed cell death. 展开更多
关键词 Triticum aestivum Nucellar cell DEGENERATION Acid phosphatase Ultracytochemical localization
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Effects of Cr content on microstructure and mechanical properties of single crystal superalloy 被引量:3
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作者 史振学 刘世忠 +1 位作者 王效光 李嘉荣 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期776-782,共7页
Two experimental single crystal superalloys with 2% Cr and 4% Cr (mass fraction) were cast in a directionally solidified furnace, while other alloying element contents were kept unchanged. The effects of Cr content on... Two experimental single crystal superalloys with 2% Cr and 4% Cr (mass fraction) were cast in a directionally solidified furnace, while other alloying element contents were kept unchanged. The effects of Cr content on the microstructure, phase stability, tensile properties at 1100 °C and stress rupture properties at 1070 °C and 160 MPa of the single crystal superalloy were investigated. The results show that the size ofγ′ phase particles become small and uniform, and the cubic shape turns a little regular with the increase of Cr content. Theγ′ directional coarsening and rafting were observed in the 2% Cr and 4% Cr alloys after long term aging (LTA) at 1100 °C. The rafting rate ofγ′ phase increased with increasing Cr content. Needle-shaped topologically close packed (TCP) phases precipitated and grew along fixed direction in both alloys. The precipitating rate and volume fraction of TCP phases significantly increased with the increase of Cr content. The tensile property of the alloy increased and the stress rupture properties of the alloy decreased with the increase of Cr content at high temperature. The increase of Cr content increased the partition ratio of TCP forming elements, Re, W, and Mo, and the saturation degrees of these elements inγ phases increased. Therefore, the high temperature phase stability of the alloy decreased with the increase of Cr content. 展开更多
关键词 single crystal superalloy Cr content MICROSTRUCTURE phase stability mechanical properties
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Heat-treated wood and its development in Europe 被引量:15
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作者 谢延军 刘一星 孙耀星 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第3期224-230,252,共7页
Efficient use of timber is a vital concern problem, especially in these regions where the forestry coverage ratio is decreasing. Studies on physical modification of wood have been taken more attention due to the incre... Efficient use of timber is a vital concern problem, especially in these regions where the forestry coverage ratio is decreasing. Studies on physical modification of wood have been taken more attention due to the increasing attentions on environmental protection. Thermal modification is emphasized and developed quickly in developing countries, especially in European countries. A large number of researches have been conducted and some industrial production plants have been built. This paper reviewed the history of heat treatment, exemplifies the industrial developments in several European countries, summarized the basic principle of heat treatment and describes the environmental characteristics. The properties of heat-treated wood and its usage are also summed up. 展开更多
关键词 Heat-treated wood DURABILITY Dimension stability Mechanical characteristics Industrial production
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Immunohistochemical Analysis of IAA in Anthers of the Photoperiod-sensitive Genic Male-sterile Rice 被引量:3
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作者 李念华 童哲 卢善发 《Acta Botanica Sinica》 CSCD 2000年第10期1045-1050,共6页
The immunohistochemical localization of IAA and the comparison of their relative levels were carried out for the first time in the anthers of Nongken 58S and its wild type Nongken 58 (Oryza sativa subsp. japonica) af... The immunohistochemical localization of IAA and the comparison of their relative levels were carried out for the first time in the anthers of Nongken 58S and its wild type Nongken 58 (Oryza sativa subsp. japonica) after long_day and short_day treatments. The distribution of free_IAA in anthers and its dynamic variation could be reflected by this method. The results showed that the IAA level in the anthers of Nongken 58S after long_day treatment was much lower than that in short_day_treated Nongken 58S and those in wild type Nongken 58 in five stages from pistil and stamen primordia formation to late uninucleate stage. The possible reasons for IAA deficiency in Nongken 58S_LD anthers and its relationship with fertility alteration were also discussed. 展开更多
关键词 rice anther auxin PHOTOPERIOD male sterility immunohistochemical localization
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Preparation of TiO2/Bi2O3 Microfibers and Their Photocatalytic Activity 被引量:1
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作者 马占营 邓玲娟 +1 位作者 李小博 范广 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第4期439-444,J0001,J0002,共8页
A series of TiO2/Bi2O3 heterojunction microfibers have been fabricated using cotton fibers as bio-templates, and characterized by XRD, SEM and UV-Vis techniques. Results reveal that Bi2O3 in the TiO2/Bi2O3 sample is a... A series of TiO2/Bi2O3 heterojunction microfibers have been fabricated using cotton fibers as bio-templates, and characterized by XRD, SEM and UV-Vis techniques. Results reveal that Bi2O3 in the TiO2/Bi2O3 sample is assigned to monoclinic and tetragonal mix-crystal phase. Fibers lengths can reach several micrometers and diameters range from 0.5 μm to 3 μm. Compared with pure TiO2 and Bi2O3, TiO2/Bi2O3 samples display better absorption in visible light region. Photocatalytic activity was evaluated by degradation of MB under visible light irradiation. TiO2/Bi2O3 microfibers exhibite much higher activity than pure TiO2 and Bi2O3, and 22.84%TiO2/Bi2O3 can achieve the decomposition of about 95%MB, which is attributed to synergistic effects of the strong visible-light absorption of TiO2/Bi2O3 microfibers and the heterojunction formed between TiO2 and Bi2O3. 展开更多
关键词 TiO2/Bi2O3 microfiber Visible light HETEROJUNCTION PHOTOCATALYSIS
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Determination of Loratadine in Human Plasma by High Performance Liquid Chromatography-Electrospray Mass Spectrometry and Studies on Its Pharmacokinetics and Relative Bioavailability 被引量:3
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作者 陈钧 高科攀 +5 位作者 史振祺 陆伟 蒋新国 荣征星 黄霞 陈红专 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第4期137-141,共5页
A new HPLC MS method to determine loratadine in human plasma was established. The method involved extracting drug with organic solvent under basic conditions. The samples were seperated by ODS column and determined ... A new HPLC MS method to determine loratadine in human plasma was established. The method involved extracting drug with organic solvent under basic conditions. The samples were seperated by ODS column and determined by mass detector. The calibration curve of loratadine was linear within the range of 0.4~100 ng·mL -1 with r=0.9995 . The recovery of this method was within 95%~104%, within day and between day RSD were less than 12%. To study the pharmacokinetics and relative bioavailability of loratadine tablets, two formulations of loratadine tablets were given to 18 healthy male volunteers according to a randomized 2 way cross over design. The C max , AUC 0 t and T max values of the two formulations were 51.89±20.18 ng·mL -1 and 52.48±22.35 ng·mL -1 ; 140.75±88.42 ng·h·mL -1 and 147.24±92.33 ng·h·mL -1 ; 0.81±0.35 h and 0.81±0.27 h respectively. Results from statistic analysis showed that there were no significant difference between the C max , AUC 0-t and T max values of the two formulations. The relative bioavailability of tablets I with respect to tablets II was 97%±13% from the AUC 0 t measurement. Bioequivalance was observed between the two tablets. 展开更多
关键词 LORATADINE HPLC MS PHARMACOKINETICS BIOAVAILABILITY
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Chemical Constituents from Roots of Semiaquilegia adoxoides 被引量:12
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作者 牛锋 谢光波 +2 位作者 崔征 陈发奎 屠鹏飞 《Journal of Chinese Pharmaceutical Sciences》 CAS 2006年第4期251-254,共4页
Semiaquilegia adoxoides ( DC. ) Makino ( Chinese name ''Tian-Kui-Zi'' ) , theonly species of genus Semiaquilegia, belongs to the Ranunculaceae family. As a perennial herbaceousplant, both the aerial pa... Semiaquilegia adoxoides ( DC. ) Makino ( Chinese name ''Tian-Kui-Zi'' ) , theonly species of genus Semiaquilegia, belongs to the Ranunculaceae family. As a perennial herbaceousplant, both the aerial parts and the roots are used in traditional Chinese medicine for differentmedications. The roots are often used to treat inflammation, snake bite, bruises and injuries,tonsillitis, mastitis, scrofula, and cancer for their antibacterial, anti-inflammatory, andantineoplastic activities. The aerial parts are used for the treatment of mastitis, bruises, andheart diseases, such as endomyocarditis. The medicinal usage of this plant prompted us toinvestigate its chemical constituents. As a result, nine compounds 1-9 ( see Figure 1) were isolatedfrom the roots of S. adoxoides. Among them, compounds 1-7 and 9 were isolated from the genusSemiaquilegia for the first time. 展开更多
关键词 Semiaquilegia adoxoides chemical constituents structure determination
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Taxonomy characterization and cadmium biosorption of fungus strain 被引量:3
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作者 曾晓希 柴立元 +2 位作者 汤建新 刘学端 杨志辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第9期2759-2765,共7页
The taxonomy characteriazation and cadmium (Cd) biosorption of the high Cd-resistant fungus M1 were investigated. The internal transcribed spacers (ITS) region and β-tubulin genes of the strain were amplified, se... The taxonomy characteriazation and cadmium (Cd) biosorption of the high Cd-resistant fungus M1 were investigated. The internal transcribed spacers (ITS) region and β-tubulin genes of the strain were amplified, sequenced and analyzed by molecular biology technology. The Cd biosorption assay was performed by shaking flask. Fourier transform infrared spectroscopy was used to analyze the mycelium. The similarity of gene sequences and phylogenetic trees show the very close relation between the strain and Paecilomyces lilacinus, and the fungus M1 was identified as P. Lilacinus. The initial pH 6 and Cd concentration about 100 mg/L are optimum. Zn and Mn have a little effect on the Cd biosorption of the strain, while Cu and Pb present obvious effects. FTIR analysis shows that the fungus adsorbs Cd by esters, anhydride, and amide. With the preferable absorption capacity, fungus M1 is considered to have good prospects in bioremediation. 展开更多
关键词 taxonomy characterization cadmium biosorption Paecilomyces lilacinu Fourier transform infrared spectroscopy
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