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Microarray technique was used to analyze the gene expression profiles of shrimp when they were challenged by WSSV and heat-inactivated Vibrio anguillarum, respectively. At 6 h post challenge (HPC), a total of 806 clones showed differential expression profile in WSSV-challenged samples, but not in Vibrio-challenged samples. The genes coding energy metabolism enzyme and structure protein were the most downregulated elements in 6 h post WSSV-challenged (HPC-WSSV) tissues. However, a total of 155 clones showed differential expression in the Vibrio-challenged samples, but not in WSSV-challenged samples. Serine-type endopeptidase and lysosome-related genes were the most upregulated elements in tissues 6 h post Vibrio challenge (HPC-Vibrio). Totally, 188 clones showed differential expression in both 6 and 12 HPC-WSSV and HPC-Vibrio samples. Most of the differentially expressed genes (185/188) were downregulated in the samples of 12 HPC-WSSV, whereas upregulated in the samples at 6 and 12 HPC-Vibrio and 6 HPC-WSSV. The expression profiles of three differentially expressed genes identified in microarray hybridization were analyzed in hemocytes, lymphoid organ, and hepatopancreas of shrimp challenged by WSSV or Vibrio through real-time PCR. The results further confirmed the microarray hybridization results. The data will provide great help for us in understanding the immune mechanism of shrimp responding to WSSV or Vibrio.

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本文分别使用基于边界元方法和高阶Boussinesq-type方程的非线性数值波浪水槽,研究了波浪破碎判据,波浪破碎能量损失以及一些特殊的波浪生成机制。基于边界元方法的数值波浪水槽使用线性元,记为DAS,其第一个改进模型修正了DAS中的积分解析公式,简称MDAS,其第二个改进模型在自由表面使用三阶元取代线性元,简称MDAS2。 鉴于Song和Banner(2002,2004)使用DAS模型提出了一个基于无量纲局部能量密度极大值平均增长率参数的破碎阈值dth,本文首先验证了dth对于MDAS和MDAS2的适用性;其次,本文考虑了海底坡度对dth的影响,结果表明dth对于中等水深下坡度小于1:100的缓坡仍然适用;再次,本文讨论了破碎阈值dth对于汇聚波的适用性,这些汇聚波具有常振幅谱,常波陡谱和PM谱,结果表明dth对这三种谱形的汇聚波都是适用的。 本文计算了常振幅谱情形时破碎能量损失对于最大能量增长率dmax的依赖性,结果表明,破碎能量损失随dmax几乎线性增长。同Banner和Pierson(2007)实验数据比对说明不同谱形的破碎能量损失随dmax的变化关系大致相同。相反,破碎能量损失随初始波陡(ak)0的变化曲线对于谱形有着显著的依赖性。此外,本文使用基于高阶Boussinesq-type方程的数值波浪水槽研究了近岸梯形潜坝上的破碎能量损失。结果指出,相对于潜坝的坡度和宽度,入射波的非线性参数和色散性参数以及潜坝的高度对于破碎能量损失具有更重要的影响。 MDAS还被用于模拟水槽中底部抬升、底部塌陷以及水中岩石坠落激发的表面波生成过程。对于底部抬升激发表面波这一过程,研究表明非线性效应对于表面波生成具有重要影响。对于底部塌陷和水中岩石坠落激发表面波过程,数值模拟结果与实验室水槽实验结果比较表明:MDAS能够有效地模拟这些生成过程。

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为探讨局部实验增温所形成的斑块效应对根田鼠栖息地利用的可能影响,通过建立开顶式增温小室模拟全球变暖,采用标志重捕法分别调查了不同放牧强度样地上4种处理内根田鼠的捕获频次.这4种处理分别为实验增温组、剪草模拟放牧组、实验增温兼剪草模拟放牧组以及对照组.研究结果表明:(1)不同的放牧强度对根田鼠的捕获频次没有显著影响;在重度放牧样地上,不论是暖季还是冷季,4种处理内根田鼠的捕获频次间的差异均达到显著水平;在轻度放牧样地上,暖季,4种处理内根田鼠的捕获频次间没有显著差异,而在冷季,这种差异则可达到显著水平(P<0.05).(2)增温小室的建立所形成的隐蔽效应对根田鼠的栖息地选择并没有显著影响,剪草处理对根田鼠的栖息地选择也没有影响,在暖季,局部实验增温对根田鼠的栖息地选择并无影响;在冷季,实验增温组与对照组间的差异显著(P<0.05),而实验增温兼剪草模拟放牧组与剪草模拟放牧组间无明显差异.结果表明,在暖季,局部实验增温对根田鼠的栖息地选择不存在明显影响,而在冷季,这种影响在实验增温组与对照组间达到显著水平,而实验增温兼剪草模拟放牧组与剪草模拟放牧组间则不明显.

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于1997—1999年在位于青海省北部的中国科学院海北高寒草甸生态系统定位站进行。选择地面筑巢的小云雀(Alauda gulgula)和灌丛筑巢的黄嘴朱顶雀(Acanthis flavirostris)为代表进行窝雏数处理实验。根据Lack假说的预报检验(1)常见窝卵数是否是最大生产力窝卵数;(2)窝雏数处理对雏鸟质量和亲鸟投入是否产生影响;(3)两种鸟的响应方式是否相同。其结果如下:①小云雀和黄嘴朱顶雀的常见窝卵数分别是3和5枚。年间变化不明显,用幼鸟出飞率作为生产力,两种鸟的扩增窝幼鸟出飞率下降,常见窝卵数(分布频率最高)等同于最大生产力窝卵数;②小云雀的幼鸟的生长参数不随窝雏数的改变而变化.而黄嘴朱顶雀有明显变化.说明窝雏数处理对后者幼鸟质量有明显影响。③用递食率作为亲鸟投资指标,小云雀亲鸟的递食率随窝雏数的增加而增加,但雏期不变;而黄嘴朱顶雀递食率不变,但雏期延长。④扩增窝雏数后,两种亲鸟表现出不同的响应方式,小云雀表现为提高单位时间递食次数,而黄嘴朱顶雀延长育幼时间。这两种方式不是通过影响雏鸟质量就是通过影响亲鸟存活率来降低子代和亲代的适合度。结果支持了自然选择将窝卵数调节到亲鸟能喂活最大数量子代的限度。即常见窝卵数就是最大生产力窝卵数的Lack假说。

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Rockmass movement due to mining steep metallic ore body is a considerable question in the surface movement and deformation issue caused by underground mining. Research on coal mining induced rockmass movement and its prediction problem have been performed for a long-term, and have achieved great progress at home and abroad. However, the rockmass movement caused by mining steep metal mine is distinctivly different from coal seam mining.. Existing surface movement laws and deformation prediction methods are not applicable to the rockmass movement caused by mining steep metal mine. So far the home and abroad research to this theory is presently at an early stage, and there isn’t mature theory or practical prediction method, which made a great impact on production. In this paper, the research object—Jinchuan nickel mine, which is typical steep metal mine, characterized by complex geological conditions, developed faults, cracked rockmass, high geostress, and prominent engineering stability problems. In addition, backfill mining method is used in the mine, the features of rockmass movement caused by this mining method are also different from other mining methods. In this paper, the laws of rock mass movement, deformation and destroy mechanism, and its prediction were analyzed based on the collection of data, detailed in-sit engineering geology survey, ground movement monitoring by GPS, theoretical analysis and numerical simulation. According to the GPS monitoring of ground surface movement, ground subsidence basin with apparent asymmetry is developing, the influence scope is larger in the upper faulted block than in the lower faulted block, and the center of ground movement is moving along the upper faulted block direction with increasing depth of mining. During the past half and seven years, the largest settlement has amounted to 1287.5mm, and corresponding horizontal displacement has amounted to 664.6mm. On the ground surface, two fissure belts show a fast-growing trend of closure. To sum up, mining steep metal mine with backfill method also exist the same serious problem of rockmass movement hazards. Fault, as a low intensity zone in rockmass, when it located within the region of mining influence, the change of potential energy mainly consumed in fault deformation associated with rockmass structure surface friction, which is the essence of displacement and stress barrier effects characterized by fault rupture zone. when steep fault located in the tensile deformation region incurred by underground excavation, no matter excavation in hangingwall or in footwall of the fault, there will be additional tensile stress on the vertical fault plane and decrease in the shear strength, and always showing characteristics of normal fault slip, which is the main reason of fault escarpment appeared on the ground surface. The No.14 shaft deformation and failure is triggered by fault activation, which showed with sidewall move, rupture, and break down features as the main form of a concentrated expression of fault effects. The size and orientation of principal stress in surrounding rock changed regularly with mining; therefore, roadway deformation and damage at different stages have different characteristics and distribution models. During the process of mining, low-intensity weak structures surface always showed the most obvious reaction, accompany with surface normal stress decrease and shear strength bring down, to some extent, occurred with relative slide and deformation. Meanwhile, the impact of mining is a relatively long process, making the structure surface effect of roadway deformation and damage more prominent than others under the influence of mining. Roadway surrounding rockmass deformation caused by the change of strain energy density field after excavation mainly belongs to elastic deformation, and the correspondented damage mainly belongs to brittle rupture, in this circumstance, surrounding rockmass will not appear large deformation. The large deformation of surrounding rockmass can only be the deformation associated with structure surface friction or the plastic deformation of itself, which mainly caused by the permanent self-weigh volume force,and long-term effect of mining led to the durability of this deformation Good pitting fill effect and supporting effect of backfill, as well as the friction of rockmass structure surface lead to obvious macro-rockmass movement with long-lag characteristics. In addition, the loss of original intensity and new structure surface arisen increased flexibility in rockmass and fill deformation in structure surface, which made the time required for rockmass potential energy translate into deformation work associated with plastic deformation and structure surface friction consumed much, and to a large extent, eliminated the time needed to do those plastic work during repeated mining, all of which are the fundamental reason of rockmass movement aftereffect more significant than before. Mining steep deposits in high tectonic stress area and in gravity stress area have different movement laws and deformation mechanism. The steep deposit, when the vertical size of the mining areas is smaller than the horizontal size of the orebody, no matter mining in gravity stress area or in high tectonic stress area, they have similar features of ground movement with mining horizontal orebody; contrarily, there will appear double settlement centers on the ground surface under the condition of mining in high tectonic stress area, while there will always be a single center under the other condition. Meanwhile the ground movement lever, scale of mining influence area and macro features of ground movement, deformation and fracture are also different from mining in gravity stress area, and the fundamental reason lies in the impact of orientation of the maximum principal stress on rock movement features in in-site rock stress field. When mining thick and steep deposit, the ground surface movement and deformation characteristic curves are significantly different from excavating the horizontal ore bed and thin steep deposit. According to the features of rockmass movement rate, the development process of mining-induced rockmass movement is divided into three stages: raising stage, steadily stage and gradually decay stage. Considering the actual exploitation situation, GPS monitoring results and macro-characteristics of surface movement, the current subsidence pattern of Jinchuan No.2 mine is in the early stage of development. Based on analysis of surface movement rate, surface subsidence rate increase rapidly when mining in double lever at the same time, and reach its peak until the exploitation model ended. When double lever mining translate into single, production decreased, surface subsidence rate suddenly start to reduce and maintain a relatively low value, and the largest subsidence center will slowly move along with the hangingwall ore body direction with increasing depth of mining, at the same time, the scope and extent of subsidence in footwall ore body will begin magnify, and a sub-settlement center will appear on ground surface, accompanied with the development and closure trend of ground fissure, the surrounding rockmass of shaft and roadway will be confronted to more frequent and severe deformation and failure, and which will have a negative impact on the overall stability of No.2 mine mining. On the premise of continuity of rockmass movement, gray system model can be used in ground rockmass movement prediction for good results. Under the condition of backfill mining step by step, the loose effect of compact status of the hard, broken rockmass led to lower energy release rate, although surrounding rockmass has high elastic energy, loose and damage occurred in the horizontal ore body, which made the mining process safety without any large geological hazards. During the period of mining the horizontal ore body to end, in view of its special “residual support role”, there will be no large scale rockmass movement hazards. Since ground surface movement mainly related to the intensity of mining speed and backfill effect, on the premise of constant mining speed, during the period of mining the horizontal ore body to end, the rate of ground surface rockmass movement and deformation won’t have sudden change.

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城市生活垃圾填埋场作为大多数国家生活垃圾的主要处理场所,也常常成为一些有毒有害元素的最终归宿地。很多含汞的废弃产品,如荧光灯管、电池、水银温度计、压力计、电开关、恒温器等,在缺乏分类回收的情况下,大多混入城市生活垃圾并最终进入垃圾填埋场。在填埋场这一特殊场合,汞可以通过物理途径、化学途径、生物途径或不同途径的结合而向大气释放,并且还可能在填埋场内形成毒性很高的甲基形态汞而释放到大气中。国外对垃圾的焚烧处理已经造成了严重的大气汞污染,但是目前对垃圾填埋场向大气释放汞的研究在国内外还不多见,我国几乎还是空白。作为城市生活垃圾的生产大国,我国每年的生活垃圾产量超过1.5亿吨,占世界的1/4以上,且近九成是以填埋法进行处理的,因此研究垃圾填埋场这一人为源向大气排放汞的通量和形态、排放汞的特点以及相关的影响因素,必将为认识该释放源对大气汞的贡献以及评估其对生态环境的影响程度提供重要的参考依据,并为制定控制垃圾填埋场汞污染的相关措施提供指导,本文在理论上和现实上都具有重要意义。 2003年10月份到2006年1月份,我们对贵阳市和武汉市的5座城市生活垃圾填埋场进行了野外实地研究。这几个填埋场包括贵阳市的高雁、大转弯、仙人脚,以及武汉市的金口和岱山垃圾填埋场,它们采用不同的垃圾填埋方式(卫生填埋和简易填埋)并处于不同的运行阶段(封闭的和运行中的)。本文从两个方面开展研究:(1)垃圾填埋场通过地表向大气释放汞的通量;(2)垃圾填埋场向大气释放汞的形态。前者利用低汞空白的石英玻璃动力学通量箱法,结合高时间分辨率的大气自动测汞仪(Tekran 2537A),现场对填埋场内不同特征的地表区域(绿化区、覆土地表、裸露生活垃圾、工作面等)进行了测定;后者利用不同的捕集材料(金管、稀HCl溶液和CarbotrapTM捕集管),对排气筒垃圾填埋气中的不同形态汞(气态总汞、单甲基汞和二甲基汞)进行预富集,并结合气相色谱、冷原子荧光等检测技术进行测定。根据同步测定的相关参数对垃圾填埋场向大气释放汞的过程和影响机制进行了探讨,对垃圾填埋场向大气的排汞量进行了估算。另外对垃圾填埋场周围环境介质中的汞分布特征进行了探讨。通过两年多的野外工作,得到以下主要结论: (1)垃圾填埋场地表与大气间的汞交换通量主要以向大气的释放为主,少数情况下(如降雨、大气汞浓度较高时)也会出现大气向地表的沉降。地表/大气间的汞交换过程具有明显的日变化特征,一般在白天中午前后达到最高,夜间降至最低,并维持在稳定的水平。汞交换过程主要与光照等气象因子有关,通量强度白天高于夜间、晴天高于阴雨天。另外,通量还与基质中的汞含量密切相关,汞含量越高,排放强度越大,生活垃圾的汞含量一般高于覆盖土壤,因而裸露的生活垃圾或工作面区域汞释放强度明显高于有土壤覆盖的区域。绿化措施(植草和种树)有效的降低了汞的释放。垃圾填埋场地表汞的释放强度暖季节高出冷季节数倍。地表/大气间的汞交换通量特征显示,垃圾填埋场向大气释放汞的主要来源为上层基质,而非填埋场内部,由于覆土隔离层的屏障作用使得填埋场内部的气态汞很难垂直向上迁移和释放。垃圾填埋场的汞释放强度与城市规模以及经济发展水平没有直接相关性。 (2)垃圾填埋场地表/大气间的汞交换通量强度由于以上因素的影响,在不同地表区域以及不同时段内都可能发生很大变化。封闭的垃圾填埋场地表/大气间的汞交换通量最高出现在汞污染的覆土区,其次为未污染的覆土区,最低为绿化区,三种区域平均的汞交换通量分别为112.8~559.1、50.7~53.6、19.7 ng Hg m-2 h-1。运行中的垃圾填埋场地表/大气间的汞交换通量最高为裸露垃圾区和工作面,最高达5609.6 ng Hg m-2 h-1,平均为57.5~664.6 ng Hg m-2 h-1;其次为老的覆土区,平均为19.6~192.5 ng Hg m-2 h-1;新盖覆土区最低,平均为-1.4~27.8 ng Hg m-2 h-1。垃圾填埋场的工作面具有最大的汞释放潜力,但是因大气汞浓度较高以及波动较大等原因,动力学通量箱法无法真实测定该区域的汞释放强度,运用美国环保局提供的面状复合工业污染源模型(ISCST3)对工作面的汞释放强度估算显示,不同天气状况下的平均释汞因子为0.93 mg Hg t-1垃圾。与全球以及区域背景土壤相比,垃圾填埋场向大气的单位面积释汞强度要高出数倍乃至数千倍。因而城市生活填埋场必将对大气汞环境,特别是局域大气汞环境造成一定影响。 (3)垃圾填埋场排气筒释放的垃圾填埋气中不同形态汞的浓度差别很大。高雁、金口和岱山垃圾填埋场排气筒的气态总汞浓度为2.0~1406.0 ng Hg m-3,3座填埋场平均分别为89.8、24.6和14.2 ng Hg m-3。气态总汞浓度主要与排气筒附近的垃圾汞含量有关,并表现出一定的日变化特征,晴天比较稳定,降雨过程中上升很快,降雨过后又恢复到降雨前的水平。这一有趣现象主要与降雨时雨水置换填埋场内的含汞气体、大气压下降、通过地表释放的通道受阻有关。高雁垃圾填埋场垃圾填埋气中的单甲基汞和二甲基汞平均浓度为1.93 ng Hg m-3和9.21 ng Hg m-3,分别占同期气态总汞的0.51%和1.79%。垃圾填埋气中的甲基形态汞浓度高出背景区域大气3个数量级以上,使得垃圾填埋场成为大气甲基汞已知不多的、重要的释放来源之一。 (4)结合垃圾填埋场不同特征地表的面积以及对应的汞交换通量强度、工作面的垃圾处理量以及汞的释放因子,估算本研究的5座垃圾填埋场每年通过地表向大气的释汞量为17~1111 g Hg yr-1,工作面贡献67%~91%,覆土区较少,绿化区最少。根据垃圾填埋气的产量以及其中不同形态汞的含量,估算高雁、金口和岱山垃圾填埋场每年通过排气筒向大气的排汞量在1~2 g Hg yr-1之间;高雁填埋场通过排气筒每年向大气释放的单甲基汞和二甲基汞为20和90 mg Hg yr-1。垃圾填埋场向大气释放汞的通道主要为地表,而排气筒的贡献仅为0.2%左右(地表+排气筒)。对全国垃圾填埋场进行的初步估算显示,2004年我国这一人为源向大气的排汞量约为600 kg Hg yr-1,占我国大气人为汞释放源的1%以下。 (5)垃圾填埋场大气中的不同形态汞浓度明显高于全球背景值,但与区域大气相当或稍高一点,部分区域有轻微污染,总体而言属于“安全”浓度范围。城市生活垃圾中的汞含量分布极不均匀,浓度为0.170~46.222 mg kg-1,几何均值0.574 mg kg-1,个别异常偏高的样品可能是被含汞的废弃产品污染了,大部分垃圾汞含量低于0.5 mg kg-1。不同垃圾填埋场覆盖土壤的汞含量差异显著,反映了填埋场所在区域的土壤背景值以及垃圾填埋活动对覆盖土壤的污染程度,有时覆土的汞含量超过区域土壤背景值的2~23倍。填埋场生长的植物因生活习性的不同汞含量分布特征也不同。高雁垃圾填埋场产生的渗滤液汞含量较低,为79.4 ng l-1,主要因为垃圾汞含量低、渗滤液呈碱性、难溶硫化物的形成以及有机/无机物对汞的吸附等。以高雁垃圾填埋场为例进行的质量平衡计算显示,每年排向渗滤液和大气的汞分别占每年输入填埋场总量的0.004%和0.3%,其余超过99%的汞仍然保留在垃圾填埋场的固体废物中,这一特点使得垃圾填埋场向大气的排汞量远低于垃圾焚烧法,后者由于高温作用使得垃圾中的汞几乎全部挥发进入大气。 (6)减少垃圾填埋场汞污染的措施包括:从源头上杜绝含汞的进入,如减少含汞产品的生产和使用,对含汞废弃产品进行专门的收集和处理;垃圾填埋以后及时进行覆土和绿化,特别是在工作面,应争取做到每日覆土;垃圾填埋场产生的气体应收集和处理,将其进行焚烧(沼气发电)可以分解其中的甲基形态汞,降低其毒性。

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We report a 75dB, 2.8mW, 100Hz-10kHz envelope detector in a 1.5mm 2.8V CMOS technology. The envelope detector performs input-dc-insensitive voltage-to-currentconverting rectification followed by novel nanopower current-mode peak detection. The use of a subthreshold wide- linear-range transconductor (WLR OTA) allows greater than 1.7Vpp input voltage swings. We show theoretically that this optimal performance is technology-independent for the given topology and may be improved only by spending more power. A novel circuit topology is used to perform 140nW peak detection with controllable attack and release time constants. The lower limits of envelope detection are determined by the more dominant of two effects: The first effect is caused by the inability of amplified high-frequency signals to exceed the deadzone created by exponential nonlinearities in the rectifier. The second effect is due to an output current caused by thermal noise rectification. We demonstrate good agreement of experimentally measured results with theory. The envelope detector is useful in low power bionic implants for the deaf, hearing aids, and speech-recognition front ends. Extension of the envelope detector to higher- frequency applications is straightforward if power consumption is inc

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Este trabajo propone tres escenarios construidos en un software dinámico que buscan relacionar el cálculo diferencial y el integral a través de la construcción comprensiva del teorema fundamental del cálculo. Dichos escenarios fueron construidos tomando como base las cuatro fases que sustentan el uso de herramientas tecnológicas en la resolución de un problema propuestas por Santos y Moreno (2013). Se resalta el acercamiento visual y empírico a través de la construcción de la derivada como la pendiente de la recta tangente a una curva, la construcción de la integral definida como el área bajo la curva en un intervalo cerrado y cómo éstas se relacionan en el teorema fundamental del cálculo.

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In this paper we propose a case base reduction technique which uses a metric defined on the solution space. The technique utilises the Generalised Shepard Nearest Neighbour (GSNN) algorithm to estimate nominal or real valued solutions in case bases with solution space metrics. An overview of GSNN and a generalised reduction technique, which subsumes some existing decremental methods, such as the Shrink algorithm, are presented. The reduction technique is given for case bases in terms of a measure of the importance of each case to the predictive power of the case base. A trial test is performed on two case bases of different kinds, with several metrics proposed in the solution space. The tests show that GSNN can out-perform standard nearest neighbour methods on this set. Further test results show that a caseremoval order proposed based on a GSNN error function can produce a sparse case base with good predictive power.