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牙鲆鱼苗长途运输技术的试验研究   总被引:3,自引:0,他引:3  
本实验对10个批次,总数为19047尾的不同规格和产地的牙鲆鱼苗长途运输效果进行了研究。结果表明,规格为9-12cm的鱼苗,在水温6-12℃,运输时间为35-50h,采用空运和低温活水车运输,运输死亡率为664尾,死亡率为3.39%,低温活水车短途运输是可行的,尽管长途车运方式成本较低,但由于应激强度较大,对鱼苗的生长性能影响较为严重,驯养10d累计死亡率最高达18.1%,这种模式不可取。低温(6℃)、小规格(9cm)的空运较适合牙鲆鱼苗长途运输。此外,本文还就运输应激反应、预防措施和药物防治进行详细的讨论。  相似文献   
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人类的地理环境,是一个包罗万象,有着无限的时、空运动。社会的进步,科学技术水平的提高,人类对地理环境的视野的拓宽,使地理学科的信息密度大幅度增长,信息质量大幅度提高。这样,地理环境的无限时、空运动与中学生的极为有限的时、空运动之间的距离迅速增大.矛盾日益尖锐。传统的教学方法提供的信息密度低,信息陈旧,  相似文献   
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1 Introduction Over the past twenty years since the enactment of the Airline Deregulation Act, the major US domestic carriers have developed hub-and-spoke structures for their op- erations. These have been instrumental in helping to reduce the overall costs of air travel to the U.S. public and to increase the travel options that are available. This effect also means that the quantity and quality of air ser- vices vary quite considerably between cities in the United States. The pattern of a…  相似文献   
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The main purpose of the paper is to introduce the concept of the Global TransPark (GTP). It is a critical time to develop air logistics infrastructure in the New Economy. The paper also presents a brief review of the air cargo industry in the Asian-Pacific region and China, in particular China‘s development in the industry as its economy has grown rapidly and globalized in the past two decades. The paper argues that China needs to develop a GTP to support its future growth, and explains why the Pearl River Delta-Hong Kong-Macao city-region or Extended Metropolitan Region (EMR) is the best location. Finally, it proposes that Zhuhai Airport, one of the five airports in the EMR, is thebest site for the GTP. New policies from Chinese government as well as close cooperation between local governmentsof Guangdong and the two Special Administrative Regions of Hong Kong and Macao will be needed to make the establishment of the GTP possible.  相似文献   
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A class of coupled system of the El Niño/La Niña-Southern Oscillation (ENSO) mechanism is studied. Using the perturbed theory, the asymptotic expansions of the solution for ENSO model are obtained and the asymptotic behavior of solution for corresponding problem is considered.  相似文献   
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