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评辽水、涎水、列水均指今滦河说
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作者 李健才 《黑龙江民族丛刊》 CSSCI 北大核心 1999年第3期59-64,共6页
辽水、水、列水当今何水,关系到古朝鲜的地理方位和燕、秦、汉与古朝鲜的边界在哪里的问题。本文根据文献与考古资料指出辽水、水、列水均指今滦河说的错误,认为辽水并无汉武帝以前和以后之分,均指今辽河;汉初的水指今清川江,后汉... 辽水、水、列水当今何水,关系到古朝鲜的地理方位和燕、秦、汉与古朝鲜的边界在哪里的问题。本文根据文献与考古资料指出辽水、水、列水均指今滦河说的错误,认为辽水并无汉武帝以前和以后之分,均指今辽河;汉初的水指今清川江,后汉到隋唐的水指今大同江;列水指今朝鲜的载宁江,而不是大同江,但列口则是指载宁江和大同江合流后的入海口。 展开更多
关键词 Pei 列水 滦河
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列氏水羚的饲养管理和繁殖
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作者 张永宾 刘义坡 +2 位作者 吴万里 高翊翔 王志永 《现代农村科技》 2022年第11期70-70,共1页
为了将石家庄市动物园所饲养的列氏水羚饲养管理好,并让其稳定繁殖,我们采用科学化的饲养管理方法,制定了一系列的规章制度,加强对饲养人员的管理和要求,将卫生清扫和日常消毒等工作做精做细。现将我园列氏水羚的饲养情况、繁殖情况和... 为了将石家庄市动物园所饲养的列氏水羚饲养管理好,并让其稳定繁殖,我们采用科学化的饲养管理方法,制定了一系列的规章制度,加强对饲养人员的管理和要求,将卫生清扫和日常消毒等工作做精做细。现将我园列氏水羚的饲养情况、繁殖情况和临床常见的疾病总结如下。 展开更多
关键词 饲养管理 繁殖
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水-岩作用模拟中饱和指数SI的灵敏度分析 被引量:9
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作者 周祖权 宋汉周 《河海大学学报(自然科学版)》 CAS CSCD 北大核心 2001年第6期90-93,共4页
以化学热力学的基本原理为基础 ,结合具体工程实例 ,综合分析了水化学分析数据误差的传递及其对饱和指数SI值的影响 ,饱和指数SI反映了水岩系列间的相互作用 .计算结果表明 ,各水化学分析数据误差对SI值的“反应”程度是不同的 ,其中“... 以化学热力学的基本原理为基础 ,结合具体工程实例 ,综合分析了水化学分析数据误差的传递及其对饱和指数SI值的影响 ,饱和指数SI反映了水岩系列间的相互作用 .计算结果表明 ,各水化学分析数据误差对SI值的“反应”程度是不同的 ,其中“反应”最为灵敏的是水的pH值 . 展开更多
关键词 化学分析数据 误差传递 -岩体系 相互作用 饱和指数SI 灵敏度
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大规模分布式光纤水听拖曳阵列及其湖试性能测试 被引量:1
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作者 龙俊求 江浪 +6 位作者 肖春 郭汝乾 严国锋 王德麟 冉曾令 龚元 饶云江 《光学学报》 EI CAS CSCD 北大核心 2024年第1期333-342,共10页
报道了一种高性能大孔径分布式光纤水听拖曳阵列,其总长度为150 m,声学传感段长度为100 m,具有192个传感单元,采用单根光纤离散增敏制备而成,无需其他分离器件。传感基元通过驻波桶标定,在20~1000 Hz,平均声压灵敏度达到-127.44 dB(re r... 报道了一种高性能大孔径分布式光纤水听拖曳阵列,其总长度为150 m,声学传感段长度为100 m,具有192个传感单元,采用单根光纤离散增敏制备而成,无需其他分离器件。传感基元通过驻波桶标定,在20~1000 Hz,平均声压灵敏度达到-127.44 dB(re rad/μPa)。阵列同时装配了自研的姿态感知模块,可实现拖曳过程的实时姿态获取。针对所研制的大规模分布式光纤水听拖曳阵列,开展了湖试综合测试,6 kn拖速下阵列声学段的倾角仅为7.8°,将192个传感单元数据波束合成后得到了16.87 dB的空间增益,传感器表现出了优异的综合性能。该高性能大规模分布式光纤水听拖曳阵列为光纤水听器发展提供了一条全新的技术路线,有力推动了基于DAS的“第三代声呐技术”的发展。 展开更多
关键词 光纤光学 光纤听器 光纤听拖曳阵 分布式光纤声波传感 声压灵敏度 姿态感知 目标轨迹跟踪
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Mapping of S-b Locus for F_1 Pollen Sterility in Cultivated Rice Using PCR Based Markers 被引量:13
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作者 李文涛 曾瑞珍 +1 位作者 张泽民 张桂权 《Acta Botanica Sinica》 CSCD 2002年第4期463-467,共5页
In cultivated rice ( Oryza sativa L.), F-1 pollen sterility is controlled by at least 6 loci of the F, pollen sterility genes. To map S-b, one of loci, rice variety Taichung 65 (T65) carrying S-b(j)/S-b(j) and its nea... In cultivated rice ( Oryza sativa L.), F-1 pollen sterility is controlled by at least 6 loci of the F, pollen sterility genes. To map S-b, one of loci, rice variety Taichung 65 (T65) carrying S-b(j)/S-b(j) and its near-isogenic line TIST2 carrying S-b(i)/S-b(i) were used to develop the mapping population. One hundred and fifty-eight microsatellite markers were selected to survey T65 and TISL2. RM13 on chromosome 5 was found to be polymorphic between them. Cosegregation indicated that RM13 was closely linked with locus S-b. Eleven RFLP markers were selected on the corresponding region from the genetic map of Rice Genome Research Program (RGP) of Japan to convert into sequence-tagged site (STS) markers. Amplicon length polymorphism (ALP) was carried out, but none of them was found to be polymorphic between T65 and TISL2. Then PCR-based RFLP (PBR) was done using six 4-nucleotide recognizing restriction endonucleases. Polymorphism was detected when PCR products of R830STS and R2213SSTS were digested with Taq I. Genetic analysis indicated that the distance between locus S-b and markers, R830STS, RM13 and R2213SSTS were 3.3 cM (centi-Morgan), 5.2 cM and 5.5 cM, respectively. These PCR-based markers could be directly used in marker-assisted selection. The technical system combining genetic mapping and PCR-based marker-assisted selection will facilitate the development of molecular breeding. 展开更多
关键词 F-1 pollen sterility genetic mapping MICROSATELLITE sequence-tagged site (STS) RICE
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Isolation of Zizania latifolia Species-specific DNA Sequences and Their Utility in Identification of Z. latifolia DNA Introgressed into Rice 被引量:5
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作者 刘振兰 董玉柱 刘宝 《Acta Botanica Sinica》 CSCD 2000年第3期324-326,共3页
根据两个植物抗病基因N和RPS2中核酸结合位点 (NBS)和富亮氨酸重复区 (LRR)中的保守序列设计了一对特异引物 ,用PCR从具有水稻 (OryzasativaL .)改良所需要的许多优良性状的水稻近缘野生种菰 (Zizanialatifolia(Griseb .)Turcz.exStapf... 根据两个植物抗病基因N和RPS2中核酸结合位点 (NBS)和富亮氨酸重复区 (LRR)中的保守序列设计了一对特异引物 ,用PCR从具有水稻 (OryzasativaL .)改良所需要的许多优良性状的水稻近缘野生种菰 (Zizanialatifolia(Griseb .)Turcz.exStapf)的基因组DNA中扩增同源片段。PCR产物经克隆后 ,分别以菰和水稻的基因组DNA为探针 ,通过点杂交对所得克隆进行了分析。点杂交结果表明 ,在所分析的 6 0个克隆中有 2个克隆是菰专化的序列 ,即它们与水稻无杂交信号。基因组DNA的Southern杂交进一步证实了这 2个克隆的专化性。为了验证一些可能的“水稻_菰”渐渗杂交系是否确实含有源自供体菰的DNA ,以这 2个克隆为探针 ,与经EcoRⅠ酶切的 5个可能的渐渗杂交系进行了Southern杂交。结果表明 ,这 2个克隆均能检测出其中的一个系含有其同源序列。这一结果为曾经报道的经一种非常规有性杂交方法将菰DNA导入水稻提供了确凿的证据。 展开更多
关键词 species_specific DNA sequence introgression lines Zizania latifolia RICE
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TIME SERIES NEURAL NETWORK MODEL FOR HYDROLOGIC FORECASTING 被引量:4
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作者 钟登华 刘东海 Mittnik Stefan 《Transactions of Tianjin University》 EI CAS 2001年第3期182-186,共5页
Time series analysis plays an important role in hydrologic forecasting,while the key to this analysis is to establish a proper model.This paper presents a time series neural network model with back propagation proced... Time series analysis plays an important role in hydrologic forecasting,while the key to this analysis is to establish a proper model.This paper presents a time series neural network model with back propagation procedure for hydrologic forecasting.Free from the disadvantages of previous models,the model can be parallel to operate information flexibly and rapidly.It excels in the ability of nonlinear mapping and can learn and adjust by itself,which gives the model a possibility to describe the complex nonlinear hydrologic process.By using directly a training process based on a set of previous data, the model can forecast the time series of stream flow.Moreover,two practical examples were used to test the performance of the time series neural network model.Results confirm that the model is efficient and feasible. 展开更多
关键词 hydrologic forecasting time series neural network model back propagation
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Using a linear array to estimate the velocity of underwater moving targets 被引量:2
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作者 严光洪 陈志菲 孙进才 《Journal of Marine Science and Application》 2009年第4期343-347,共5页
A new method uses a linear array that takes advantage of underwater physical sound fields to estimate the velocity of an underwater moving target. The mathematical model was established by considering the geometric re... A new method uses a linear array that takes advantage of underwater physical sound fields to estimate the velocity of an underwater moving target. The mathematical model was established by considering the geometric relationship between the moving target installed with only two transducers to radiate sound of different frequencies and the linear array. In addition, deterministic maximum likelihood and signal phase matching algorithms were introduced to effectively find the directions of arrival (DOAs) of the sound sources of the two transducers installed on the target. Factors causing velocity measurement errors were considered. To track the target, a linear array with a compass, a pressure transducer, a signal conditioner and a digital recorder was configured. Relevant requirements for the array parameters were derived. The simulation showed that a 16-element array with an aperture of less than lm can measure velocity with relative error of no more', than 4% when including typical system errors. Anechoic pool and reservoir experiments confirmed these results. 展开更多
关键词 underwater velocity measurement linear array direction of arrival (DOA) deterministicmaximum likelihood signal phase matching
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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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Segmental Duplications Are Common in Rice Genome 被引量:1
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作者 王石平 刘克德 张启发 《Acta Botanica Sinica》 CSCD 2000年第11期1150-1155,共6页
Segmental duplications on rice (Oryza sativa L.) chromosomes 8, 9, 11, and 12 were studied by examining the distributions of sequences resolved by 13 probes detecting multiple copies of DNA sequences. Four of the hyb... Segmental duplications on rice (Oryza sativa L.) chromosomes 8, 9, 11, and 12 were studied by examining the distributions of sequences resolved by 13 probes detecting multiple copies of DNA sequences. Four of the hybridization bands detected by a repetitive sequence probe, rTRS, were mapped to the ends of all the four chromosomes. Two or three of the bands detected by each of the other 12 probes were also mapped to different chromosomes. The bands detected by the same probe usually occurred in similar locations of different chromosomes. Loci detected by different DNA probes were often similarly arranged on different chromosomes. Chromosomes 8 and 9 showed colinearity of marker loci arrangement indicating a possible common origin. A segment on chromosome 9 was also very similar to the previously reported duplicated fragments on the ends of chromosomes 11 and 12 which were also detected in this study, indicating a likely common origin. Moreover, the various degrees of distributional similarity of the segments suggest a complex relationship among the chromosomes in the evolution of the rice genome. These results support the proposition that chromosome duplication and diversification may be a mechanism for the origin and evolution of the chromosomes in the rice genome. 展开更多
关键词 chromosomal duplication repetitive sequence molecular mapping EVOLUTION r€
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浦江赋
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作者 何流 《天工》 2014年第1期140-141,共2页
东汉丰安故邑,而今魅力浦江。地处浙中,衢通八面。优踞天时地利,更兼政善人和,故物阜民淳,农丰商盛。钟灵毓秀,历尽天华:群山藏韵,峰岩峡岭骚诗苑;列水放歌,河涧溪湾纵画坛。壮哉!飞来峰下清泉涌,玄鹿山中瀑布鸣。 八十件出土瓷陶,上... 东汉丰安故邑,而今魅力浦江。地处浙中,衢通八面。优踞天时地利,更兼政善人和,故物阜民淳,农丰商盛。钟灵毓秀,历尽天华:群山藏韵,峰岩峡岭骚诗苑;列水放歌,河涧溪湾纵画坛。壮哉!飞来峰下清泉涌,玄鹿山中瀑布鸣。 八十件出土瓷陶,上山遗址文明在;一万年沧桑变幻,稻作田园史迹存。迟来后辈,对话先民,犹见:东升红日,西蔚彩霞,北飘瑞雪,南播春风。 展开更多
关键词 江赋 上山遗址 玄鹿山 诗苑 丰安 来峰 列水 天华 阜民 稻作
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一九九○年工程建设概预算定额制订、修订计划
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《铁路工程造价管理》 1990年第3期32-32,共1页
关键词 概预算定额 修订计划 工程建设 容主 列水 南荆 书堂 浦琳 耳定 海飘
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Genome-wide Detection and Analysis of Alternative Splicing for Nucleotide Binding Site-Leucine-Rich Repeats Sequences in Rice
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作者 顾连峰 郭荣发 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第3期247-257,共11页
Alternative splicing is a major contributor to genomic complexity and proteome diversity, yet the analysis of alternative splicing for the sequence containing nucleotide binding site and leucine-rich repeats (NBS-LRR... Alternative splicing is a major contributor to genomic complexity and proteome diversity, yet the analysis of alternative splicing for the sequence containing nucleotide binding site and leucine-rich repeats (NBS-LRR) domain has not been explored in rice (Oryza sativa L.). Hidden Markov model (HMM) searches were performed for NBS-LRR domain. 875 NBS-LRR-encoding sequences were obtained from the Institute for Genomic Research (TIGR). All of them were used to blast Knowledge-based Oryza Molecular Biological Encyclopaedia (KOME), TIGR rice gene index (TGI), and Universal Protein Resource (UniProt) to obtain homologous full-length cDNAs (FL-cDNAs), tentative consensus sequences, and protein sequences. Alternative splicing events were detected from genomic alignment of FL-cDNAs, tentative consensus sequences, and protein sequences, which provide valuable information on splice variants of genes. These sequences were aligned to the corresponding BAC sequences using the Spidey and Sim4 programs and each of the proteins was aligned by tBLASTn. Of the 875 NBS-LRR sequences, 119 (13.6%) sequences had alternative splicing where multiple FL-cDNAs, TGI sequences and proteins corresponded to the same gene. 71 intron retention events, 20 exon skipping events, 16 alternative termination events, 25 alternative initiation events, 12 alternative 5' splicing events, and 16 alternative 3' splicing events were identified. Most of these alternative splices were supported by two or more transcripts. The data sets are available at http://www.bioinfor.org. Furthermore, the bioinformatics analysis of splice boundaries showed that exon skipping and intron retention did not exhibit strong consensus. This implies a different regulation mechanism that guides the expression of splice isoforms. This article also presents the analysis of the effects of intron retention on proteins. The C-terminal regions of alternative proteins turned out to be more variable than the N-terminal regions. Finally, tissue distribution and protein localization of alternative splicing were explored. The largest categories of tissue distributions for alternative splicing were shoot and callus. More than one-thirds of protein localization for splice forms was plasma membrane and cytoplasm. All the NBS-LRR proteins for splice forms may have important function in disease resistance and activate downstream signaling pathways. 展开更多
关键词 alternative splicing BIOINFORMATICS NBS-LRR homologous sequence RICE
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Effect of 2,4-D on Microtubule Reorientation in Rice Root Tips
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作者 刘向东 卢永根 《Acta Botanica Sinica》 CSCD 2000年第4期367-372,共6页
The reorientation of microtubules (MTS) in roots of Oryza sativa L. treated with 2,4_D was studied using confocal laser scanning microscopy. In the control (the roots were not treated with 2,4_D), different distributi... The reorientation of microtubules (MTS) in roots of Oryza sativa L. treated with 2,4_D was studied using confocal laser scanning microscopy. In the control (the roots were not treated with 2,4_D), different distribution patterns of MTS were observed in the different growth zones of root tips. MTS of the cortical cells were randomly aligned in the zone of cell division. They were transversely arranged in the cortical cells of the zone of cell elongation; and obliquely oriented in the root hair zone. After treatment with 2,4_D, MTS displayed distinct changes with reorientation in the cortex of the root tip coupling with the inhibition of root growth. MTS changed their orientation in the cortical cells of the zone of cell division from being randomly oriented to transversely oriented when incubated in 1 mg/L 2,4_D for 1 h. However, they were recovered and became randomly oriented when the roots were treated with 1 mg/L 2,4_D for 24 h. An array of MTS, which was different from that in the control, was observed in the cortical cells of the zone of cell elongation in the roots treated with 1 mg/L 2,4_D for 1 h. After treatment with 10 mg/L 2,4_D for 1 h, the MTS in the cortical cells of the zone of cell division became transversely reorientated, but the pattern of MTS distribution was different from that in the 1_hour treatment of 1 mg/L 2,4_D. MTS were hardly detected in the same type of cells when roots were submerged in 10 mg/L 2,4_D for 24 h. When roots were incubated in 10 mg/L 2,4_D for 1 h, the MTS of the cortical cells in the zone of cell elongation became randomly oriented, and much more randomly when the roots were treated for 24 h. 展开更多
关键词 RICE root tip MICROTUBULE 2 4_D
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Molecular characterization of cyanobacterial diversity in Lake Gregory, Sri Lanka 被引量:3
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作者 Dhammika MAGANA-ARACHCHI Rasika WANIGATUNGE Madhushankha LIYANAGE 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第4期898-904,共7页
Eutrophication or the process of nutrient enrichment of stagnant waters due to excessive use of fertilizer is becoming a critical issue worldwide. Lake Gregory, an artificial lake situated in Nuwara Eliya, Sri Lanka w... Eutrophication or the process of nutrient enrichment of stagnant waters due to excessive use of fertilizer is becoming a critical issue worldwide. Lake Gregory, an artificial lake situated in Nuwara Eliya, Sri Lanka was once a very attractive landscape feature and recreational area attracting a large number of visitors. Rapid urbanization in surrounding areas and the consequent intensification of agricultural and industrial activities led to eutrophication and siltation in the lake. Present study was conducted to detect cyanobacterial diversity and their ability to produce hepatotoxic microcystins using polymerase chain reaction (PCR)-based techniques. Twenty five water samples (surface and bottom) were collected from the lake and total nitrogen and total carbon were estimated. Cyanobacterial cultures were grown in appropriate media and microscopic observations were used to determine the morphological diversity of cyanobacteria isolated from different sites. Genomic DNA was isolated and purified from cyanobacteria using Boom's method. DNA samples were analyzed by PCR with oligonucleotide primers for 16S rRNA gene and mcyA gene of the operon that encodes a microcystin synthetase. The 16S rRNA gene sequences revealed the presences of cyanobacteria belong to Synechococcus sp., Microcystis aeruginosa, Calothrix sp., Leptolyngbya sp., Limnothrix sp., order Oscillatoriales and order Chroococcales. The sequences obtained from this study were deposited in the database under the accession numbers (GenBank: GU368104-GU368116). PCR amplification of mcyA primers indicated the potential for toxin formation of isolated M. aeruginosa from Lake Gregory. This preliminary study shows that the Lake Gregory is under the potential risk of cyanobacterial toxicity. Clearly more work is needed to extend this finding and clarify if other cyanobacterial isolates have genetic potential to produce microcystin since this lake is utilized for recreational activities. 展开更多
关键词 EUTROPHICATION boom's method PCR MICROCYSTIN mcyA gene
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Effect of Eu^3+-doping on morphology and fluorescent properties of neodymium vanadate nanorod-arrays 被引量:1
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作者 Li TIAN Shan-min CHEN +4 位作者 Qiang LIU Jie-ling WU Rui-ni ZHAO Shan LI Li-juan CHEN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第4期1031-1037,共7页
Tetragonal structural(t-NdVO4)nanorod-arrays were fabricated by simple one-pot hydrothermal method.The phase,morphology and microstructure of NdVO4 were characterized by X-ray diffractometer,scanning electron microsco... Tetragonal structural(t-NdVO4)nanorod-arrays were fabricated by simple one-pot hydrothermal method.The phase,morphology and microstructure of NdVO4 were characterized by X-ray diffractometer,scanning electron microscope(SEM),transmission electron microscope(TEM),dispersive X-ray spectrometer(EDS)and selected area electron diffraction(SAED)techniques.t-NdVO4 nanorods are single-crystalline with a length of 100 nm and a diameter of 25 nm,which grow orientally along the direction of(112)crystalline plane and self-assemble to form nanorod-arrays.The results show that Eu^3+-doping interrupts the formation of NdVO4 nanorod-arrays,and then leads to the red-shift of the strongest luminescence emission of Nd3+transition from 4D3/2 state to 4I11/2 and decreases its intensity of the fluorescence emission at 400 nm sharply.The research results have some reference values to optimize the photoluminescence performance of rare earth vanadates. 展开更多
关键词 Eu^3+-doping MORPHOLOGY fluorescent properties neodymium vanadate nanorod-arrays hydrothermal method
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Sparse underwater acoustic OFDM channel estimation based on superimposed training
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作者 赵俊义 孟维晓 贾世楼 《Journal of Marine Science and Application》 2009年第1期65-70,共6页
A superimposed training (ST) based channel estimation method is presented that provides accurate estimation of a sparse underwater acoustic orthogonal frequency-division multiplexing (OFDM) channel while improving... A superimposed training (ST) based channel estimation method is presented that provides accurate estimation of a sparse underwater acoustic orthogonal frequency-division multiplexing (OFDM) channel while improving bandwidth transmission efficiency. A periodic low power training sequence is superimposed on the information sequence at the transmitter. The channel parameters can be estimated without consuming any extra system bandwidth, but an unknown information sequence can interfere with the ST channel estimation method, so in this paper, an iterative method was adopted to improve estimation performance. An underwater acoustic channel's properties include large channel dimensions and a sparse structure, so a matching pursuit (MP) algorithm was used to estimate the nonzero taps, allowing the performance loss caused by additive white Gaussian noise (AWGN) to be reduced. The results of computer simulations show that the proposed method has good channel estimation performance and can reduce the peak-to-average ratio of the OFDM channel as well. 展开更多
关键词 channel estimation superimposed training sparse underwater acoustic channel
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Existence of Microsatellites in Expressed Sequence Tags of Common Carp (Cyprinus carpio L.) Available in GenBank dbEST Database 被引量:8
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作者 HU Jingjie WANG Xiaolong HU Xiaoli BAO Zhenmin 《Journal of Ocean University of China》 SCIE CAS 2006年第1期12-20,共9页
Common carp expressed sequence tags (ESTs) were analyzed for the existence of microsatellites, or simple sequence repeats (SSRs). In the NCBI dbEST database, a total of 10612 sequences were registered before Decem... Common carp expressed sequence tags (ESTs) were analyzed for the existence of microsatellites, or simple sequence repeats (SSRs). In the NCBI dbEST database, a total of 10612 sequences were registered before December 31, 2004. A complete search of 2-6 nucleotide microsatellites resulted in the identification of 513 SSR-containing ESTs, accounting for 4.8% of the total. Cluster analysis indicated that 73 sequences of SSR-containing ESTs fell into 27 groups and the remaining 440 ESTs were independent. A total of 467 unique SSR-containing ESTs were identified. These EST-SSRs contained a vari- ety of simple sequence types, and di- and tri-nucleotide repeats were the most abundant, accounting for 42.1% and 27.9% of the whole, respectively. Of the dinucleotide repeats, CA/TG was the most abundant, followed by GA/TC. BLASTx search showed that 38.1% of the SSR loci could be associated with genes or proteins of known or unknown function. BLASTx searches of SSR-containing ESTs also showed high frequencies (98/179) of hits on zebrafish sequences. 展开更多
关键词 common carp microsatellites ESTS data mining
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Pretreatment of coking wastewater using anaerobic sequencing batch reactor (ASBR) 被引量:10
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作者 李冰 孙英兰 李玉瑛 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第11期1115-1123,共9页
A laboratory-scale anaerobic sequencing batch reactor (ASBR) was used to pretreat coking wastewater. Inoculated anaerobic granular biomass was acclimated for 225 d to the coking wastewater, and then the biochemical me... A laboratory-scale anaerobic sequencing batch reactor (ASBR) was used to pretreat coking wastewater. Inoculated anaerobic granular biomass was acclimated for 225 d to the coking wastewater, and then the biochemical methane potential (BMP)of the coking wastewater in the acclimated granular biomass was measured. At the same time, some fundamental technological factors, such as the filling time and the reacting time ratio (tf/tr), the mixing intensity and the intermittent mixing mode, that affect anaerobic pretreatment of coking wastewater with ASBR, were evaluated through orthogonal tests. The COD removal efficiency reached 38%~50% in the stable operation period with the organic loading rate of 0.37~0.54 kg COD/(m3.d) at the optimum conditions of tf/tr, the mixing intensity and the intermittent mixing mode. In addition, the biodegradability of coking wastewater distinctly increased after the pretreatment using ASBR. At the end of the experiment, the microorganism forms on the granulated sludge in the ASBR were observed using SEM (scanning electron microscope) and fluoroscope. The results showed that the dominant microorganism on the granular sludge was Methanosaeta instead of Methanosarcina dominated on the inoculated sludge. 展开更多
关键词 Anaerobic sequencing batch reactor (ASBR) Coking wastewater Anaerobic pre-treatment
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Analysis of Short-term Heavy Precipitations in a Regional Heavy Rainstorm in Shannxi Province
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作者 王楠 《Agricultural Science & Technology》 CAS 2013年第3期411-416,共6页
[Objective] This study aimed to analyze the cause of the generation of short-term heavy precipitations in a regional heavy rainstorm in Shannxi Province. [Method] Taking a heavy rainstorm covering most parts of Shaanx... [Objective] This study aimed to analyze the cause of the generation of short-term heavy precipitations in a regional heavy rainstorm in Shannxi Province. [Method] Taking a heavy rainstorm covering most parts of Shaanxi Province in late July 2010 as an example, data of five Doppler weather radars in Shaanxi Province were employed for a detailed analysis of the evolution of the heavy rainstorm pro- cess. [Result] Besides the good large-scale weather background conditions, the de- velopment and evolution of some mesoscale and small-scale weather systems direct- ly led to short-term heavy precipitations during the heavy rainstorm process, involv- ing the intrusion of moderate IS-scale weak cold air and presence of small-scale wind shear, convergence and adverse wind area. In addition, small-scale convection echoes were arranged in lines and formed a "train effect", which would also con- tribute to the generation of short-term heavy precipitation. [Conclusion] This study provided basic information for more clear and in-depth analysis of the formation mechanism of short-term heavy precipitations. 展开更多
关键词 Short-term heavy precipitation Doppler weather radar Adverse wind area: Train effect
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