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黑龙江乱泥沟金矿成矿条件与找矿方向 总被引：1，自引：0，他引：1
乱泥沟矿区第四系砂金矿产丰富，是寻找岩金的有利靶区。区内出露的古元古代变质岩系地层的原岩为泥质粉砂岩和中基性海底火山岩，其Au含量高，是金矿成矿的初始矿源层。区内NE，NW向构造发育，所发现的矿体均受控于NW向断裂，呈脉和复脉状产于构造蚀变带及其次一级的层间破碎带中，成矿物质简单，矿体品位和厚度变化系数较小，为中—低温蚀变岩型金矿床。利用物化探测量手段，圈出具找矿意义的组合异常，通过工程查证发现金矿体。在综合研究矿区地质特征及物化探异常的基础上总结了找矿标志，并指出下一步有利的找矿区段。 相似文献
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Estivation, hibernation, and starvation are indispensable inactive states of sea cucumbers Apostichopus japonicus in nature and in culture ponds. Generally, temperature is the principal factor that induces estivation or hibernation in the sea cucumber. The present study provided insight into the physiological adaptations of A. japonicus during the three types of inactivity (hibernation, estivation, and starvation) by measuring the oxygen consumption rates (Vo2) and biochemical compositions under laboratory conditions of low (3°C), normal (17°C) and high (24°C) temperature. The results show that the characteristics of A. japonicus in dormancy (hibernation and estivation) states were quite different from higher animals, such as fishes, amphibians, reptiles, and mammals, but more closely resembled a semi-dormant state. It was observed that the shift in the A. japonicus physiological state from normal to dormancy was a chronic rather than acute process, indicated by the gradual depression of metabolic rate. While metabolic rates declined 44.9% for the estivation group and 71.7% for the hibernation group, relative to initial rates, during the 36 d culture period, metabolic rates were not maintained at constant levels during these states. The metabolic depression processes for sea cucumbers in hibernation and estivation appeared to be a passive and an active metabolic suppression, respectively. In contrast, the metabolic rates (128.90±11.70 μg/g h) of estivating sea cucumbers were notably higher (107.85±6.31 μg/g h) than in starving sea cucumbers at 17°C, which indicated that the dormancy mechanism here, as a physiological inhibition, was not as efficient as in higher animals. Finally, the principle metabolic substrate or energy source of sea cucumbers in hibernation was lipid, whereas in estivation they mainly consumed protein in the early times and both protein and lipid thereafter. 相似文献
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对虾、青蛤和江蓠混养系统氮磷收支的实验研究 总被引：8，自引：0，他引：8
为减少养殖污水中营养盐的排放量,降低对近海水质的污染,采用海水陆基围隔实验法,对凡纳滨对虾(Litope-naeus vannamei)、青蛤(Cyclina sinesis)和菊花心江蓠(Gracilaria lichevoides)不同混养系统的氮(N)、磷(P)收支状况进行了实验研究。结果表明:实验中的单养组投放的饵料占N总输入的75.5%,占P总输入的93.6%,混养组投放的饵料占N总输入的54.7%~64.8%,占P总输入的81.6%~88.7%;在支出项目中,单养组和混养组收获的养殖生物分别占N总输入的25.0%和44.4%~51.5%,占P总收入的11.2%和25.1%~31.8%;底泥沉积N,P为其主要支出项目,单养组和混养组分别占总输入的45.1%和30.0~32.5%,68.3%和50.3%~57.1%,其中混养组N,P的底泥沉积量低于单养组。 相似文献
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通过海水陆基围隔实验,研究了凡纳滨对虾(Litopenaeus vannamei)与青蛤(Cyclina senensis)、菊花心江蓠(Gracilaria lichevoides)投饵混养的适宜配比、经济效益和生态效益。实验结束时对虾的体重、成活率和净产量分别为5.30~6.12g,62.96%~78.21%和1 065.0~1 367.6kg.hm-2。青蛤体重和净产量分别为6.85~7.15g,和51~328kg.hm-2。菊花心江蓠净产量为3 900~9 380kg.hm-2。混养系统的经济效益和生态效益均优于对虾单养。在本实验条件下,混养系统的最佳结构为凡纳滨对虾30ind.m-2,青蛤30ind.m-2,菊花心江蓠200g.m-2;其N,P绝对利用率分别为52.94%和26.09%。 相似文献
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发展虾池生态系统功能,采用围隔实验方法,研究了凡纳滨对虾(Litopenaenus vannamei)、青蛤(Cyclina sinensis)、江蓠(Gracilaria lichevoides)混养生态系统能量收支和能量转换效率。结果表明,实验期间所接受的总太阳辐射能为1 854.4MJ.m-2。各混养处理光合能显著高于对照。混养各处理光能利用率为0.23%~0.36%,随江蓠放养密度的增加而升高,显著高于对虾单养(0.14%)(p<0.05)。各混养处理与对虾单养相比,系统总能转化率分别提高了113.4%,94.2%,116.02%和41.91%,单位净产量耗总能则平均比对虾单养降低62.22%,但各处理饲料能转化率差异不明显(p>0.05)。各处理底泥沉积能量为0.71~1.38MJ,分别占总输出能的3.66%~8.61%,沉积量平均比对虾单养(1.65MJ)降低20.14%。可以看出,江蓠和青蛤混养可以显著提高对虾池光能利用率和投入系统总能的转化效率,降低虾池能量的沉积,进而大幅提高系统能量利用率。 相似文献
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评估结构耐撞性能最可靠的方法是实尺度碰撞试验,然而对于大尺度结构物的碰撞试验,因其耗资巨大而不易开展,适当开展比例模型试验可以为简化解析算法及数值仿真计算提供验证依据,也可在一定程度上评估结构的耐撞性能。但是在进行碰撞模型试验时,材料应变率的敏感性会使得缩尺模型的动态响应与实尺度结构结果出现偏差,模型试验得到的数据与实际结构的动响应不完全遵循相似关系,这就限制了相似理论在大型结构物冲击问题上的应用。本文给出了一种通过改变冲击质量来修正应变率效应的方法,不同于传统量纲分析法中选取时间、质量和长度为基本量纲,而是以冲击质量、初始冲击速度和动态应力代替,得到计及应变率效应的质量相似关系。以此为基础,将该修正方法应用于船舶-自升式海洋平台的碰撞分析中。研究结果表明,该修正方法可以有效降低由于应变率效应而造成的缩尺误差,修正后的缩尺模型在碰撞冲击载荷下的位移、碰撞力和撞击时间等动态响应参数与实尺度模型结果的一致性更好。本文研究成果可以为大型结构物冲击模型试验设计提供技术支撑。 相似文献
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鼠尾藻生长、藻体成分及其生境的初步研究 总被引：1，自引：0，他引：1
对威海小石岛附近海区鼠尾藻(Sargassum thunbergii)的生长、藻体成分和水体中氮、磷等营养元素的月份变动情况进行了初步研究.结果表明,研究海区水体中硝酸氮的含量具有明显的月份变化,5～10月含量较低,11～4月含量较高;相对于硝酸态氮,氨氮的含量较低,随月份变动也较小;总无机氮的含量变化与硝酸氮含量变化趋于一致;总无机磷含量随月份的变动也较大,在2～6月含量较低,11～1月含量较高.鼠尾藻生长有着明显的月份变化,4～5月生长最快,6～7月藻体达到最大长度;侧枝一般在4月开始出现,7月达到最长.对鼠尾藻体内的碳、氮、磷、碳水化合物以及色素进行测定的结果表明,鼠尾藻体内的碳含量变化较小,一般在25.6%～33.0%之间;氮的含量变化较大,12～5月含量较高,超过3%,7～11月含量较低,低于3%;磷的含量也具有很大的波动,在11～4月含量较高,5～10月含量较低.色素含量具有明显的月份变化,12～3月含量较高,7～10月含量较低.碳水化合物含量在4～7月时较高,最低出现在8～9月. 相似文献
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Estivation, hibernation, and starvation are indispensable inactive states of sea cucumbers Apostichopus japonicus in nature and in culture ponds. Generally, temperature is the principal factor that induces estivation or hibernation in
the sea cucumber. The present study provided insight into the physiological adaptations of A. japonicus during the three types of inactivity (hibernation, estivation, and starvation) by measuring the oxygen consumption rates
(Vo2) and biochemical compositions under laboratory conditions of low (3°C), normal (17°C) and high (24°C) temperature. The results
show that the characteristics of A. japonicus in dormancy (hibernation and estivation) states were quite different from higher animals, such as fishes, amphibians, reptiles,
and mammals, but more closely resembled a semi-dormant state. It was observed that the shift in the A. japonicus physiological state from normal to dormancy was a chronic rather than acute process, indicated by the gradual depression
of metabolic rate. While metabolic rates declined 44.9% for the estivation group and 71.7% for the hibernation group, relative
to initial rates, during the 36 d culture period, metabolic rates were not maintained at constant levels during these states.
The metabolic depression processes for sea cucumbers in hibernation and estivation appeared to be a passive and an active
metabolic suppression, respectively. In contrast, the metabolic rates (128.90±11.70 μg/g h) of estivating sea cucumbers were
notably higher (107.85±6.31 μg/g h) than in starving sea cucumbers at 17°C, which indicated that the dormancy mechanism here,
as a physiological inhibition, was not as efficient as in higher animals. Finally, the principle metabolic substrate or energy
source of sea cucumbers in hibernation was lipid, whereas in estivation they mainly consumed protein in the early times and
both protein and lipid thereafter. 相似文献
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