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目的:探索有效地从载体上分离钉螺的阻/灭螺工程技术的实施方法和理论依据.方法:采用负重 法、浸泡法和离心法,研究噪声、照度、色彩、离心力、pH及不同盐溶液等物理、化学因素对钉螺吸附力的影响.结果:噪声为110分贝(db)时,钉螺100％脱落.pH由低到高时,脱落率呈类“U”型变化,pH超过9.7时,微小的变化即能使脱离率大幅度急剧增长.离心率达823*10－5牛顿(N)时,脱落率为100％.照度小于4146勒克司(Lx)时,钉螺脱落率升高,在16587Lx强光照射下,5分钟即100％脱落.含NH的盐溶液对钉螺吸附能力影响较小,而在含Na+和Ca2+的盐溶液中脱落率较高,两者有显著性差异.红色光照下,钉螺脱离率高,与黄、蓝、绿及无色相比有十分显著性差异.结论:以上结果表明钉螺的吸附能力与环境密切相关,改变其赖以生存的环境,即可改变其吸附能力.在水利阻/灭螺工程中形成高速旋转的水流,以增大离心力和噪声,增加光照强度,以及红色光照在分离和沉降池中的运用,均可提高水利阻/灭螺工程的效果.“,”To explore the implementing methods and basis of theory of the snail obstructing/killing project and technology separating Oncomelania from the carries. METHODS: Effects of physical and chemical factors such noise,light,centrifuge force, pH and various solutions of different salts on adhesive ability of Oncomelania have been investigated with adding weight,immersing and centrifuge mothods. RESULTS: Noise reached 110 decibles the snails fell completely(100%). pH ranged from low to high, falling rate changed like“U”shape, change slope became even and slow in acid environment while slope became precipitous in basic environment,particalarly when pH surpassed 9: 72 and tiny change would make falling rate in crease ripidly. Centrifugal force reached 823*10-5N,fall rate would get to 100%. Fall rate would increas when light is less than 4146Lx. Infive minutes falling rate would reached 100% in 16587Lx light. Salt solution with NH had minor influence on solution with Na+ and Ca++, difference in tow solution was significant. When snails exposed to red light, their falling rate were more significant, compared with yollow,green, blue and nocolour light. CONCLUSION: The above results indicated that adhesive ability of snails had close relation with their environment. The adhesive ability of snails would change if the environment that they depended on changed. Therefore vertical water to enhance centifagal forces and noise,increasing strength of light and red light used in seperation and subsidence basin might be expected to increase seperation rate in the snail-obstructing/killing project.