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Detection of Exogenous Gene Copies in Transgenic Soybean by Taqman Quantitative PCR Technique 被引量:1
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作者 仇有文 张明辉 +5 位作者 高学军 曲波 敖金霞 袁肖寒 刘营 霍楠 《Agricultural Science & Technology》 CAS 2011年第4期497-499,553,共4页
[Objective] Taqman Quantitative PCR technique was adopted to detect the copies of exogenous nos terminator in transgenic hybrid soybean.[Method] With soybean Lectin as the endogenous reference gene,and gene complex DN... [Objective] Taqman Quantitative PCR technique was adopted to detect the copies of exogenous nos terminator in transgenic hybrid soybean.[Method] With soybean Lectin as the endogenous reference gene,and gene complex DNA in non-GMO soybeans as the endogenous reference standard,the method of gradient dilution was used for separately calculate Ct value of endogenous reference gene and plasmid DNA and correlation standard curve equation of logarithm of copies,and then to calculate the copies of samples through substituting thus-obtained Ct into the standard curve equation.[Result] The standard curve equation of endogenous reference gene is y=-3.422x+35.201,R2=0.998;and the standard curve equation of exogenous gene is y=-3.348x+34.890,R2=0.999.Nos terminator and its lower boundary sequences in transgenic soybean is of single copy.[Conclusion] The study has provided a theoretical basis for determining exogenous gene copies in transgenic soybean. 展开更多
关键词 Real-time PCR Transgenic hybrid soybean copies LECTIN Boundary sequence of nos terminator gene
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ASYMPTOTICALLY ISOMETRIC COPIES OF l_P (1≤P<∞) AND c_0 IN BANACH SPACES
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作者 陈东阳 《Acta Mathematica Scientia》 SCIE CSCD 2006年第2期281-290,共10页
Let X be a Banach space. If there exists a quotient space of X which is asymptotically isometric to l^1, then X contains complemented asymptotically isometric copies of l^1. Every infinite dimensional closed subspace ... Let X be a Banach space. If there exists a quotient space of X which is asymptotically isometric to l^1, then X contains complemented asymptotically isometric copies of l^1. Every infinite dimensional closed subspace of l1. contains a complemented subspace of l1 which is asymptotically isometric to l1. Let X be a separable Banach space such that X^* contains asymptotically isometric copies of lp (1 〈 p 〈∞). Then there exists a quotient space of X which is asymptotically isometric to lq (1/p + 1/q=1). Complemented asymptotically isometric copies of co in K(X, Y) and W(X, Y) are discussed. Let X be a Gelfand-Phillips space. If X contains asymptotically isometric copies of co, it has to contain complemented asymptotically isometric copies of co. 展开更多
关键词 Asymptotically isometric copies of complemented asymptoticaly isometriccopies of
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An analysis of silver candlesticks from a casting point of view:originals,copies,forgeries
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作者 Jaromir Audy Emil Evin 《China Foundry》 SCIE CAS 2010年第1期68-75,共8页
Collecting silver artefacts has traditionally been a very popular hobby.Silver is addictive,therefore the number of potential collectors and investors appears to grow each year.Unfortunately,increases in the interest ... Collecting silver artefacts has traditionally been a very popular hobby.Silver is addictive,therefore the number of potential collectors and investors appears to grow each year.Unfortunately,increases in the interest and buying potentials resulted in a number of forgeries manufactured and introduced to the open antique market.The items such as early silver candlesticks dictate a very high price,for many high quality fakes show very good appearances and matching similarities with originals.Such copies are traditionally manufactured by casting using the original items as patterns.Small details and variances in design features,position and shape of hallmarks,including the final surface quality are usual features to distinguish the fakes from the originals.This paper presents results of a study conducted on several silver candlesticks,including two artefacts bearing features of those produced in the mid 18th century,one original Italian candelabrum from Fascist era,and small candlesticks made in the early 20th century.Also,the paper presents some interesting contemporary coins-replicas of many those produced in different countries.The coins were offered for sale by unscrupulous dealers via auctions and e-bays.Finally the main results and findings from this study are discussed from a manufacturing point of view,such as fabrication technology,surface quality and hallmarks,which will help the collectors,dealers and investors to detect and avoid forgeries. 展开更多
关键词 candlesticks candelabra originals copies forgeries SILVER manufacturing technology hallmarks
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UNIFORMLY COPIES OF l^(N)_(P)IN THE SPACES OF POLYNOMIALS
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作者 Dumitru POPA 《Acta Mathematica Scientia》 2026年第1期112-118,共7页
Let n≥2 be a natural number,1≤p≤∞and X a Banach space.We prove that if X^(*)containsλ-uniformly copies of l^(k)^(p),then:■contains■-uniformly copies of■.in the case p^(*)>n(ii)■containsλ^(n)-uniformly cop... Let n≥2 be a natural number,1≤p≤∞and X a Banach space.We prove that if X^(*)containsλ-uniformly copies of l^(k)^(p),then:■contains■-uniformly copies of■.in the case p^(*)>n(ii)■containsλ^(n)-uniformly copies of l^(k)_(∞)in the case p^(*)≤n.This complete a result of S.Dineen’s from 1995. 展开更多
关键词 polynomials on Banach spaces uniformly copies of lnp finitely represented
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Unraveling the missing heritability of amyotrophic lateral sclerosis:Should we focus more on copy number variations?
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作者 Maria Guarnaccia Valentina La Cognata +2 位作者 Giulia Gentile Giovanna Morello Sebastiano Cavallaro 《Neural Regeneration Research》 2026年第5期1997-1998,共2页
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the progressive degeneration of upper and lower motor neurons in the brainstem and spinal cord,leading to muscle weakness,para... Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by the progressive degeneration of upper and lower motor neurons in the brainstem and spinal cord,leading to muscle weakness,paralysis,and respiratory failure (Morgan and Orrell,2016). 展开更多
关键词 degeneration upper lower motor neurons unraveling neurodegenerative disorder missing heritability amyotrophic lateral sclerosis copy number variations
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“Lion King”sells 3 million copies in return to video
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《小作家选刊(小学生版)》 2003年第11期52-52,共1页
Simba has come out roaring again in itsDVD debut. “The Lion King”sold 3 million copies in the first twodays of its new home-video release,distributor Disney saidThursday.
关键词 Lion King sells 3 million copies in return to video
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Degree Conditions on Copies of Forests in Graphs
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作者 Xiao-Dong Chen Shuai-Jun Chen Ming-Chu Li 《Journal of the Operations Research Society of China》 EI CSCD 2023年第3期667-672,共6页
For a graph G,letμ(G)=min{max{d(x),d(y)}:x≠y,xy∉E(G),x,y∈V(G)}if G is non-complete,otherwise,μ(G)=+∞.For a given positive number s,we call that a graph G satisfies Fan-type conditions ifμ(G)≥s.Supposeμ(G)≥s,t... For a graph G,letμ(G)=min{max{d(x),d(y)}:x≠y,xy∉E(G),x,y∈V(G)}if G is non-complete,otherwise,μ(G)=+∞.For a given positive number s,we call that a graph G satisfies Fan-type conditions ifμ(G)≥s.Supposeμ(G)≥s,then a vertex v is called a small vertex if the degree of v in G is less than s.In this paper,we prove that for a forest F with m edges,if G is a graph of order n≥|F|andμ(G)≥m with at most max{n−2m,0}small vertices,then G contains a copy of F.We also give examples to illustrate both the bounds in our result are best possible. 展开更多
关键词 Fan-type conditions FOREST COPY Small vertex
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Asymptotically Isometric Copies of l^∞ in Some Banach Lattices
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作者 AN Gui Mei 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2008年第3期575-578,共4页
In this paper, we show that any a-complete Banach lattice, with a σ-order semicontinuous but not σ-order continuous norm, contains an asymptotically isometric copy of l^∞. We also get that the Fenchel-Orlicz space ... In this paper, we show that any a-complete Banach lattice, with a σ-order semicontinuous but not σ-order continuous norm, contains an asymptotically isometric copy of l^∞. We also get that the Fenchel-Orlicz space with the Orlicz norm may not contain an asymptotically isometric copy of l^∞. 展开更多
关键词 asymptotically isometric copy Banach lattice Fenchel-Orlicz space.
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On Asymptotically Isometric Copies of l~β(0 < β < 1)
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作者 Chen ZHI Mei Mei SONG 《Journal of Mathematical Research and Exposition》 CSCD 2010年第6期1032-1038,共7页
We get the characterizations of the family of all nonnegative, subadditive,β-absolutely homogeneous and continuous functionals defined on X, when the ;3-normed space X contains an asymptotically isometric copy of l^... We get the characterizations of the family of all nonnegative, subadditive,β-absolutely homogeneous and continuous functionals defined on X, when the ;3-normed space X contains an asymptotically isometric copy of l^β. Moreover, it is proved that if a closed bounded β-convex subset K of a β-normed space contains an asymptotically isometric β-basis, then K contains a closed β-convex subset C which fails the fixed point property. 展开更多
关键词 asymptotically isometric copy β-normed space β-absolutely homogeneous
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Single-nucleotide polymorphisms and copy number variations drive adaptive evolution to freezing stress in a subtropical evergreen broadleaved tree:Hexaploid wild Camellia oleifera 被引量:1
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作者 Haoxing Xie Kaifeng Xing +3 位作者 Jun Zhou Yao Zhao Jian Zhang Jun Rong 《Plant Diversity》 2025年第2期214-228,共15页
Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wil... Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wild C.oleifera can serve as a case for studying the molecular bases of adaptive evolution to freezing stress.Here,47 wild C.oleifera from 11 natural distribution sites in China and 4 relative species of C.oleifera were selected for genome sequencing.“Min Temperature of Coldest Month”(BIO6)had the highest comprehensive contribution to wild C.oleifera distribution.The population genetic structure of wild C.oleifera could be divided into two groups:in cold winter(BIO6≤0℃)and warm winter(BIO6>0℃)areas.Wild C.oleifera in cold winter areas might have experienced stronger selection pressures and population bottlenecks with lower N_(e) than those in warm winter areas.155 singlenucleotide polymorphisms(SNPs)were significantly correlated with the key bioclimatic variables(106 SNPs significantly correlated with BIO6).Twenty key SNPs and 15 key copy number variation regions(CNVRs)were found with genotype differentiation>50%between the two groups of wild C.oleifera.Key SNPs in cis-regulatory elements might affect the expression of key genes associated with freezing tolerance,and they were also found within a CNVR suggesting interactions between them.Some key CNVRs in the exon regions were closely related to the differentially expressed genes under freezing stress.The findings suggest that rich SNPs and CNVRs in polyploid trees may contribute to the adaptive evolution to freezing stress. 展开更多
关键词 Adaptive evolution Camellia oleifera Copy number variations Freezing stress POLYPLOID Single-nucleotide polymorphisms
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Hua Shou and his Elaboration of the Fourteen Meridians (Shi Si Jing Fa Hui)
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作者 Yongxuan Liang Hongmei Kaneko 《Journal of Traditional Chinese Medical Sciences》 2025年第4期445-446,共2页
Hua Shou(1304-1386)styled himself Ying Ning Sheng.He was also known as Hua Boren.His ancestral home was in Xiang Town,Xu Prefecture(present Xuchang,Henan province).His birth place was Yizhen,Jiangsu province.Later he ... Hua Shou(1304-1386)styled himself Ying Ning Sheng.He was also known as Hua Boren.His ancestral home was in Xiang Town,Xu Prefecture(present Xuchang,Henan province).His birth place was Yizhen,Jiangsu province.Later he moved to Yuyao,Zhejiang province.He was one of the distinguished practitioners of the late Yuan and early Ming dynasties.His writings include Elaboration of the Fourteen Meridians(Shi Si Jing Fa Hui),Notes on Handwritten Copy of Basic Questions(Du Su Wen Chao),The Essentials for Physicians(Zhen Jia Shu Yao). 展开更多
关键词 handwritten copy basic questions du Fourteen Meridians Notes Handwritten Copy elaboration fourteen meridians shi Shi Si Jing Fa Hui hua borenhis Essentials Physicians Hua Shou
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Prolonged passive vibration of Achilles and patellar tendons decreases effort perception during subsequent cycling tasks
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作者 Florian Marchand Benjamin Pageaux +1 位作者 Nicolas Forestier Florian Monjo 《Journal of Sport and Health Science》 2025年第5期124-133,共10页
Background:The perception of effort is a key determinant of endurance performance and a barrier to physical activity in inactive populations.From a neurophysiological viewpoint,effort perception is thought to arise fr... Background:The perception of effort is a key determinant of endurance performance and a barrier to physical activity in inactive populations.From a neurophysiological viewpoint,effort perception is thought to arise from the brain processing of an efference copy of the motor command in sensory areas.However,recent research suggests that feedback from muscle spindles plays a significant role in this perception.In this study,tendon vibration protocols were employed to attenuate sensory feedback during subsequent cycling exercises.The aim was to assess whether vibration would increase cycling power output,muscle activation,and heart rate at fixed perceived effort intensities.Methods:Fifteen healthy young participants completed 2 experimental visits(vibration and sham).In each visit,participants performed two 3-min cycling bouts,1 at a moderate perceived effort intensity and 1 at a strong perceived effort intensity,before(pre)and after(post)an actual or a sham vibration protocol.Vibration was applied bilaterally on the patellar and Achilles tendons for 10 min.Power output,heart rate,and vastus lateralis electromyography(VL EMG)were recorded and averaged for each bout.Absolute values as well as relative change(%)between pre and post conditions were compared across sham and vibration conditions.Results:At moderate perceived effort,power output,heart rate,and VL EMG increased post-vibration compared to pre-vibration(p<0.05),while no difference was observed in the sham condition.At strong perceived effort,power output and VL EMG decreased post-sham(p<0.05)but remained unchanged post-vibration.Moreover,the relative change between pre and post conditions was significantly higher in the vibration conditions compared to the sham condition for all variables.Conclusion:This study shows that tendon vibration reduces effort perception during subsequent cycling bouts.This effect is likely a consequence of vibration-induced reduction in muscle spindle reafferent signaling to the brain,but this mechanism remains to be further elucidated.From an applied perspective,these findings highlight tendon vibration as a promising tool for enhancing physical activity engagement. 展开更多
关键词 Efference copy Muscle spindles PACING Physical activity Sense of effort
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Biological and translational attributes of mitochondrial DNA copy number:Laboratory perspective to clinical relevance
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作者 Deepak Parchwani Ragini Singh Digisha Patel 《World Journal of Methodology》 2025年第3期38-55,共18页
The mitochondrial DNA copy number(mtDNAcn)plays a vital role in cellular energy metabolism and mitochondrial health.As mitochondria are responsible for adenosine triphosphate production through oxidative phosphorylati... The mitochondrial DNA copy number(mtDNAcn)plays a vital role in cellular energy metabolism and mitochondrial health.As mitochondria are responsible for adenosine triphosphate production through oxidative phosphorylation,maintaining an appropriate mtDNAcn level is vital for the overall cellular function.Alterations in mtDNAcn have been linked to various diseases,including neurodegenerative disorders,metabolic conditions,and cancers,making it an important biomarker for understanding the disease pathogenesis.The accurate estimation of mtDNAcn is essential for clinical applications.Quantitative polymerase chain reaction and next-generation sequencing are commonly employed techniques with distinct advantages and limitations.Clinically,mtDNAcn serves as a valuable indicator for early diagnosis,disease progression,and treatment response.For instance,in oncology,elevated mtDNAcn levels in blood samples are associated with tumor aggressiveness and can aid in monitoring treatment efficacy.In neurodegenerative diseases such as Alzheimer’s and Parkinson’s,altered mtDNAcn patterns provide insights into disease mechanisms and progression.Understanding and estimating mtDNAcn are critical for advancing diagnostic and therapeutic strategies in various medical fields.As research continues to uncover the implications of mtDNAcn alterations,its potential as a clinical biomarker is likely to expand,thereby enhancing our ability to diagnose and manage complex diseases. 展开更多
关键词 Mitochondrial DNA copy number Mitochondrial DNA Quantitative polymerase chain reaction Cancer Neurodegenerative disease AGING
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Health risks of rare earth elements exposure:Impact on mitochondrial DNA copy number and micronucleus frequency
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作者 Shiyi Hong Yali Zhang +6 位作者 Qiaojian Zhang Zekang Su Guiping Hu Li Wang Shanfa Yu Xiaojun Zhu Guang Jia 《Journal of Environmental Sciences》 2025年第5期150-160,共11页
Toxic effects in terms of mitochondria and hereditary substances have been characterized in vitro for individual rare earth elements,while,the joint effects of mixed elements exposure in the population remain ambiguou... Toxic effects in terms of mitochondria and hereditary substances have been characterized in vitro for individual rare earth elements,while,the joint effects of mixed elements exposure in the population remain ambiguous.Based on the Occupational Chromate Exposure Dynamic Cohort of China,this study investigated the relationship between 15 blood rare earth elements(cerium,dysprosium,erbium,europium,gadolinium,holmium,lanthanum,lutetium,neodymium,praseodymium,samarium,terbium,thulium,yttrium,and ytterbium)and mitochondrial DNA copy number(MtDNACN)as well as peripheral blood lymphocyte micronucleus frequency(MNF).The elastic net was used to select elements highly correlated with effect indicators,whose dose-response relationships were further illustrated by restricted cubic splines.Bayesian kernel regressionwas employed to explore the combined effects of elements and the contributions of single element.The results showed that most rare earth elementswere positively correlatedwith effect indicators,with yttrium showing the strongest association(β(95%CI):0.139(0.1089–0.189)for MtDNACN,0.937(0.345–1.684)for MNF).In the mixed exposure model,with the exposure level fixed at the 50th percentile as the reference,the effect estimates on MtDNACN and MNF increased by 0.228 and 0.598 units,respectively,at the 75th percentile.The single effect analysis implied that yttrium,lanthanum and terbium contributed the most to the elevation of MtDNACN,while yttrium posed the highest risk for genetic damage,accordingly,we provided recommendations to prioritize these elements of concern.In addition,we observed a chief mediating effect of MtDNACN on the elevation of MNF caused by lanthanum,whereas further mechanistic exploration is required to confirm this finding. 展开更多
关键词 Rare earth elements Mitochondrial DNA copy number Micronucleus frequency Mixed effect
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Linux卷管理系统Snapshot技术的分析与研究 被引量:5
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作者 董欢庆 李战怀 +1 位作者 王彦龙 石维盛 《计算机工程》 CAS CSCD 北大核心 2004年第2期55-57,共3页
快照技术是产生在线热备份的重要技术手段,其实现相当复杂。文章对Linux内核的卷管理系统的快照技术进行了分析和研究,讨论了与快照技术相关的数据结构、源逻辑卷的写请求处理以及快照逻辑卷的读请求处理。
关键词 卷管理 快照 地址映射 在线备份 COPY on WRITE
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TCP/IP协议卸载技术性能与实现的研究 被引量:3
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作者 朱宏峰 刘天华 +1 位作者 刘杰 常桂然 《小型微型计算机系统》 CSCD 北大核心 2007年第4期609-614,共6页
本文通过分析当前计算机系统主要通信瓶颈,建立模型分析其卸载后的性能,得出协议卸载与节点处理能力、网络带宽、网卡处理能力以及需要处理的应用程序、网络数据包的强度有关的结论,得出了他们之间理想状态下的最优解.建立并初步实现TO... 本文通过分析当前计算机系统主要通信瓶颈,建立模型分析其卸载后的性能,得出协议卸载与节点处理能力、网络带宽、网卡处理能力以及需要处理的应用程序、网络数据包的强度有关的结论,得出了他们之间理想状态下的最优解.建立并初步实现TOE通信平台,实现零拷贝,利用Linux开源特点实现相应的软控制程序并结合ML403开发板实现相应的硬处理功能,实现简单数据包的收发. 展开更多
关键词 TOE Zero—Copy 吞吐率
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CoPy/C催化剂应用碱性介质氧还原催化的电化学性能(英文) 被引量:2
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作者 徐莉 乔锦丽 +3 位作者 丁蕾 胡隆宇 刘玲玲 王海江 《物理化学学报》 SCIE CAS CSCD 北大核心 2011年第10期2251-2254,共4页
利用碳黑(Vulcan XC-72R)中加入硫酸钴和吡啶(Py)作为催化剂前驱体,经溶剂分散热处理构建了一类新型的高效氧还原CoPy/C复合催化剂.并运用循环伏安法(CV)和旋转圆盘电极(RDE)技术研究了不同Co含量的CoPy/C催化剂在碱性介质中对氧还原的... 利用碳黑(Vulcan XC-72R)中加入硫酸钴和吡啶(Py)作为催化剂前驱体,经溶剂分散热处理构建了一类新型的高效氧还原CoPy/C复合催化剂.并运用循环伏安法(CV)和旋转圆盘电极(RDE)技术研究了不同Co含量的CoPy/C催化剂在碱性介质中对氧还原的电催化活性.结果表明:Co的存在对氧的催化剂活性位的形成有重要影响,800℃下所制备的10%Co30%Py/C(质量分数)复合催化剂表现出最佳的氧还原催化活性.以其制备的气体扩散电极在3.0 mol·L^(-1)KOH电解质溶液(O_2气氛)中0.014 V(相对于标准氧电极(RHE))即可产生明显的氧还原电流.同40%Py/C相比,10%Co30%Py/C催化氧还原的起峰电位正移了71 mV,同时表现出明显的极限扩散电流.在-0.16 V时电流密度达到最大值,电流密度为1.0 mA·cm^(-2),半波电位在-0.07 V.透射电镜分析表明所制备的碳黑载吡啶钴(10%Co30%Py/C)催化剂平均粒径为20 nm. 展开更多
关键词 碱性燃料电池:CoPy/C 热处理:氧还原反应:循环伏安:旋转圆盘电极
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Isolation of Rice EPSP Synthase cDNA and Its Sequence Analysis and Copy Number Determination 被引量:1
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作者 徐军望 魏晓丽 +3 位作者 李旭刚 陈蕾 冯德江 朱祯 《Acta Botanica Sinica》 CSCD 2002年第2期188-192,共5页
In order to isolate the total cDNA of rice (Oryza sativa L.) epsps gene, RT-PCR was carried out with template of rice first-strand cDNA and primers designed according to rice EPSP synthase genomic sequence obtained in... In order to isolate the total cDNA of rice (Oryza sativa L.) epsps gene, RT-PCR was carried out with template of rice first-strand cDNA and primers designed according to rice EPSP synthase genomic sequence obtained in previous study. A 1 585-bp cDNA fragment was amplified and cloned. The 1 585-bp cDNA contains an open reading frame (ORF) comprising of 1 533 nucleotides (nt) which encodes a 511 residue polypepetides, including 67 amino acids chloroplast transit peptide and 444 amino acids EPSP synthase mature peptide. A comparison between the EPSP synthase of different sources indicates that the mature peptide shows more than 51% identity except for the fungi EPSP synthase and the transit peptide shows considerably less sequence conservation. The copy number of rice epsps gene is estimated to be one copy per haploid rice genome using southern blot. RT-PCR indicated that rice epsps gene is expressed in rice leaves, endosperms and roots and has the highest expression level in leaves. 展开更多
关键词 rice EPSP synthase cDNA sequence sequence analysis copy numbers EXPRESSION
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COPYCAD软件在逆向工程中的应用 被引量:2
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作者 张海 姜羡 付伟 《华东交通大学学报》 2005年第2期119-122,共4页
随着计算机技术和自动化测量技术的高速发展,逆向工程已经成为一种重要的设计手段,同时也出现了很多专门用于逆向工程的软件.本文通过对COPYCAD的介绍,展示了这些软件工作的一般步骤,总结了他们的一些共性.
关键词 逆向工程 CAD软件 COPY 自动化测量技术 应用 计算机技术 设计手段 软件工作
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加工中心在线测量系统在自由曲面COPY加工中的应用研究 被引量:1
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作者 关雄飞 呼刚义 王荪馨 《制造技术与机床》 CSCD 北大核心 2012年第5期107-109,共3页
在没有三坐标测量机等不具备逆向设计条件的情况下,通过编制用户宏指令对在线测量系统进行控制,收集和处理模型曲面测量数据,则可以实现类似三坐标测量机自动扫描曲面测量和实现仿形加工的功能。阐述了COPY加工的原理、程序的编制方法... 在没有三坐标测量机等不具备逆向设计条件的情况下,通过编制用户宏指令对在线测量系统进行控制,收集和处理模型曲面测量数据,则可以实现类似三坐标测量机自动扫描曲面测量和实现仿形加工的功能。阐述了COPY加工的原理、程序的编制方法、加工误差分析及为保证加工精度应采取的措施。 展开更多
关键词 加工中心 在线测量宏程序 自由曲面 COPY加工
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