990 resultados para Mochnacki, Maurycy, 1804-1834.


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This is the Restormel Fish Counter, Annual Report 2002 produced by the Environment Agency South West Region on March 2003. The report presents the daily upstream counts of migratory salmonids recorded on the River Fowey at Restormel Weir fish counting station (SX 107 613) in 2002. Data contained within this report covers the period of the commercial migratory salmonid net buy-back scheme and the National Spring Salmon Bylaws. The fish counter at Restormel is a resistivity based system (Logie 2100A - Aquantic limited) and is installed on the weir at Restormel approximately 2 km upstream of the tidal limit. The run pattern observed for salmon and sea trout in 2002 was generally consistent with that of previous years. The upstream salmon / large sea trout count for 2002 was 1804.

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A knowledge of the specific composition of Ceylon fish fauna is essential to any programme of development of commercial fisheries, or the study of Ceylon's ichthyology and the need for cataloguing it has been keenly felt for many years. The need for cataloguing the whole of Ceylon's flora and fauna was stressed by the Natural Science Section of the Ceylon Association for the Advancement of Science during its 1952 annual sessions and it was then that the writer agreed to help satisfy this need by compiling an up-to-date check list of species of two families of fishes, the Clupeidae and the Carangidae, which are important in the beach seine fishery which he was studying at that time. In the course of this work it was decided to expand the check-list to make it comprehensive of all species of fish that have been recorded from Ceylon to date and to supply keys for their identification. This has involved a screening of the pioneer works of Bennet (1834) and Day (1878-1889) and the many subsequent references to Ceylon fish scattered through various scientific journals and other publications, some of them long out and now almost unobtainable.

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本发明公开了一种电刺激噪声消除仪,包括两根用于采集生物电信号的微电极,所述微电极的信号输出端经噪声抑制电路后输出,所述噪声抑制电路包括差分放大电路和电阻电容补偿电路,所述微电极采集的电信号经电阻电容补偿电路,分别输入差分放大电路的两个输入端,经差分放大之后输出。利用本发明所述电刺激噪声(伪迹)消除仪,可以消除大于生物电信号本身约40倍以上的电刺激噪声,从而有利于实现将电刺激和单位放电记录这两项重要的神经电生理研究技术有机的结合起来,对神经电生理的研究具有积极的促进作用。

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DNA指纹个体识别技术是保护遗传学研究中的一种非常重要的手段。为了准确地识别天鹅洲保护区中的每一头长江江豚以开展保护遗传学及其它相关研究 ,并实施有效的种群管理 ,本研究应用 4个微卫星座位初步构建了该群体的DNA指纹图谱 ,并利用此图谱成功地对不同时期在保护区捕获的江豚进行了个体识别研究。结果显示微卫星指纹技术是一种适用于长江江豚个体识别研究的可靠手段

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分别在 2 0 0 1年和 2 0 0 2年用国家标准《水质 -微型生物群落监测 -PFU法》在香港米浦自然保护区的基围塘和红树林中监测水质 .在 3个基围塘中共鉴定出 91种原生动物 ,为香港地区的首次记录 .同时在群落级水平上分析了4种生态结构参数和 5种功能参数 .用化学的方法成功地监测出在此 3个基围塘的PFU挤出液中 pp′-DDE和PCB的浓度 ,并且获得两年一致性的结果 .本文化学和生物学结合的研究结果为测定水中超痕量持久性有机污染物 (POPs)的环境暴露与生态毒性提供了一种新的尝试 .图

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<正> 众所周知,我国鳖类动物中分布最广,数量最多的是中华鳖[Pelodiscus sinensis(Wieg-mann,1834)],近几年来,进行大规模人工养殖的对象,多数也是中华鳖。中华鳖的背甲都是具肋板8对。作者曾经先后仔细地观察了中华鳖42个背甲骨胳,全部恒定具8对肋板,而且没有构造上显著的变异。然而,在湖南省境内却出产一种鳖,外形与中华鳖非常相似,成鳖体型大小亦相差不很多(当地有经验的捕鳖或养鳖能手,能够加以辨认)。我国历史上就有过记载,最早追溯到明朝的晚期,我国伟大的药物学家李时珍,编写于1

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A wrap method adaptation combined with AutoCAD2005 and Scion Image for Windows were used to determine the surface area of a fish. Compared with the corresponding r(2) and F of many models, the most accurate formula: S = 752.15W(0.675) (r(2) = 0.999, F = 18362.94, P < 0.0001) for estimating the surface area of common carp was obtained. Similarly, the fin formula: S = 1834.12W(0.708) (r(2) = 0.992, F = 2690.47, P < 0.0001) was also obtained for the same purpose. It was proven that these two formulae gave good estimates of surface and fin areas of four strains of common carp: Yellow-river carp, fancy carp, mirror carp and Xingguo red carp.

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We report a systematical study on the molecular beam epitaxy growth and optical property of (GaAs1-xSbx/In-y Ga1-yAs)/GaAs bilayer quantum well (BQW) structures. It is shown that the growth temperature of the wells and the sequence of layer growth have significant influence on the interface quality and the subsequent photoluminescence (PL) spectra. Under optimized growth conditions, three high-quality (GaAsSb0.29/In0.4GaAs)/GaAs BQWs are successfully fabricated and a room temperature PL at 1314 nm is observed. The transition mechanism in the BQW is also discussed by photoluminescence and photoreflectance measurements. The results confirm experimentally a type-II band alignment of the interface between the GaAsSb and InGaAs layers.

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This paper describes the design and fabrication process of a two-dimensional GaAs-based photonic crystal nanocavity and analyzes the optical characterization of cavity modes at room temperature. Single InAs/InGaAs quantum dots (QDs) layer was embedded in a GaAs waveguide layer grown on an Al0.7Ga0.3As layer and GaAs substrate. The patterning of the structure and the membrane release were achieved by using electron-beam lithography, reaction ion etching, inductively coupled plasma etching and selective wet etching. The micro-luminescence spectrum is recorded from the fabricated nanocavities, and it is found that some high-order cavity modes are clearly observed besides the lowest-order resonant mode is exhibited in spite of much high rate of nonradiative recombination. The variance of resonant modes is also discussed as a function of r/a ratio and will be used in techniques aimed to improve the probability of achieving spectral coupling of a single QD to a cavity mode.

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目前大多数水印算法采用线性相关的方法检测水印,但是,当原始媒体信号不服从高斯分布,或者水印不是以加嵌入方式嵌入到待保护的媒体对象中时,该方法存在一定的问题.数字水印的不可感知性约束决定了水印检测是一个弱信号检测问题,利用这一特性,首先从图像DCT(discrete cosine transfom)交流变换系数的统计特性出发,应用广义高斯分布来建立其统计分布模型,然后将水印检测问题转化为二元假设检验问题,以非高斯噪声中弱信号检测的基本理论作为乘嵌入水印的理论检测模型,推导出优化的乘嵌入水印检测算法,并对检测算法进行了实验.结果表明,对于未知嵌入强度的乘水印的盲检测,提出的水印检测器具有良好的检测性能.因此,该检测器能在数字媒体数据的版权保护方面得到了实际的应用.

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本文根据即时通讯(IM)的协议模型,在TCP层和即时通讯协议层分析了阻断即时通讯的可能性,分别提出了基于TCP层和即时通讯协议层的协议分析的阻断策略.在TCP层,通过插入FIN报文或RST报文,以关闭TCP连接(特别是与登录服务器的连接);在即时通讯协议层,通过对相应字段的值进行设置,使客户端进入不活动状态.为使阻断策略能够有效地实施,本文也提出了一个消息驱动的实现算法.通过对Yahoo! Messenger的阻断实验,证明了本文提出的方法能够高效地完成阻断任务(平均数据包量不超过2.5个).用统计分析的方法对它们的性能进行比较,结果表明各种方法的效率在不同的背景流量下没有显著的差异,通过消息驱动算法实现的基于协议分析的阻断策略,其工作效率不受背景流量的影响.另外,即时通讯数据的触发方式,使得发送的阻断包的数量与背景流量无关,也不对网络负载造成明显的影响.本文的工作为实施即时通讯的阻断提供了有效的解决方案.

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琼东南盆地是南海西北陆缘上一个北东走向的伸展裂陷带,向西与北西走向的莺

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对石碌铁矿一块具有代表性的新鲜矽卡岩铁矿石标本进行了岩石薄片显微镜观