12 resultados para Dung roller beetles

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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We determined the mitochondrial MA (mtDNA) sequences of two luminous beetles (Arthropoda, Insecta, Coleoptera), Rhagophthalmus lufengensis from Yunnan, China and Rhagophthalmus ohbai from Yaeyama Island, Japan. We identified all the 37 mtDNA genes of R. l

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Lightweight materials, structures and coupling mechanisms are very important for realizing advanced flight vehicles. Here, we obtained the geometric structures and morphologies of the elytra of beetles and ascertained its coupling zone by using the histological section technique and SEM. We set up a three-dimensional motion observing system to monitor the opening and closing behaviour of elytra in beetles and to determine the motion mechanism. We constructed a force measuring system to measure the coupling forces between elytra. The results show that elytra open and close by rotating about a single axle, where the coupling forces may be as high as 160 times its own bodyweight, the elytra coupling with the tenon and mortise mechanism, surface texture and opening angle between elytra heavily influence the coupling forces. These results may provide insights into the design mechanism and structure for future vehicles of flight.

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二十世纪八十年代,当比利时冶金研究中心(CRM)开发出CO_2激光毛化冷轧辊技术后,尝试用YAG激光进行轧辊毛化一直吸引着众多的研究者,这是因为YAG(1.06μm)激光波长比CO_2(10.6μm)激光波长短一个量级,材料对YAG激光有更高的吸收率,并用YAG激光可以聚焦到更小的光斑尺寸,同时使用电信号驱动的声光开关技术便于对毛化分布进行可设定控制。但是用传统声光调制的YAG激光虽然可以碇以很高的脉冲频率(>30kHz),但单脉冲有量仅为10mJ左右,难以达到辊面毛化粗糙度的要求,因此人们认为YAG激光用于毛化的主要困难是脉冲能量太小。

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生物荧光是活体生物自身可以发光的有趣生命现象.具有这一现象的生物存在于生物四界中,但目前关于这一现象的研究报道主要来自于昆虫,尤其是以萤火虫为代表的发光甲虫的研究.文章对发光甲虫的分类地位、生物荧光发生的原理、发光器官的类型、闪光的"开关"机制、生物荧光的生物学意义及其相关行为学研究进展等进行了详细介绍.此外,还简要提及了荧光生物及其荧光酶的应用.这对了解及探讨生物荧光现象、加强对中国的发光甲虫及其它发光生物的研究及保护利用具有一定的借鉴作用.

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我国的生物质能资源主要是农业废弃物、禽畜类便和林业废弃物。生物质能的利用方式有:直接燃烧、产生沼气等可燃气、发电、转化为液体燃料和加工成高密度的固体燃料。文中对几种利用方式进行了讨论。


To describe the process technology of biomass energy resource utilization from agricultural waste, forestry waste, poultry dung , which including thermal energy utilization in terms of bio-gases produced by direct burning, power generation, transferring to bio-energy, liquefied fuels and processing high-density solid fuels.

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长白山地区为保护较为完善的原始森林区,物种丰富,因此被选为论文的研究区域.这里地处温带,气候寒冷,水甲虫种类分布有着一定的独特性.该项研究通过对不同海拔高度的不同水体中水甲虫的采样,研究了长白山北坡水甲虫的种类、生物多样性及其颁与环境因子的相关性.通过调查和研究,发现长白山水甲虫已记录的种类共有8科37属67种,其中占种群优势的是龙虱科和水龟虫科.同时,通过对文献的系统研究,发现中国有已记录的水甲虫共21科141属916种,比原记录601种(杨集昆,1994)多215种.在对长白山北坡水甲虫区系研究的同时,对生物多样性指数进行了分析,结果表明长白山北坡的水甲虫生物多样性各项指标均显示出该地区水甲虫物种较为丰富,物种均匀度高.在研究水甲虫的分布与环境因子的关系时发现,不同水体中环境因子对水甲虫分布的影响不同,活水水体中起主要作用的因子是植被密度和水流速度,静水水体中起主要作用的因子是海拔和腐殖化程度.

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川西北高寒草甸位于青藏高原东部地区,是我国四大牧区之一,也是长江和黄河等江河源区的重要水源涵养功能区。近几十年来,大量牦牛粪便被牧民作为生物能源、肥料或者食用菌产业的原料而利用,为草原生态系统的养分平衡增加了生态风险。鉴于在青藏高原地区针对牦牛粪便的相关研究尚未见报道,本文从粪便和土壤养分相互变化趋势的角度出发,研究了粪便在夏秋两季的分解状况和粪便其下及其周围土壤的养分变化。通过此研究,将有助于了解牦牛粪便在自然状态下的分解速率以及粪便对土壤养分及土壤微生物生物量的影响,为粪便对草地土壤生态系统的贡献提供概念性认识,同时也为高寒草甸草地这种脆弱生态系统的可持续管理提供理论依据。 针对牦牛粪便自身养分释放及其对土壤在时间和空间尺度上的影响,本文通过模拟牛粪堆积,在不同时间和固定区域内对牛粪和土壤进行了夏秋两季的采样测定,分析了牛粪及土壤NO3--N、NH4+-N、速效K、无机P、有机C、全N 和全P 含量随时间的变化趋势。得到如下结果: 1. 在研究区域内,牛粪对草地生态系统具有较强的养分(N、P)贡献能力。据初步统计,其估值大致为氮素699~932 kg ha-1,P 素为110~147 kg ha-1。牛粪(湿重、干重)在夏秋季节的分解速率具有较大差异,夏季显著快于秋季。夏季牛粪湿重、干重在2 个月左右之后分别降为初期的14%和24%,而秋季同期分别降为35%和52%。牛粪养分(NO3--N、NH4+-N、速效K、无机P、有机C、全N 和全P)的分解速率在夏季也要显著快于秋季。秋季经过2 个月左右的分解之后,牛粪以上含量分别降至初始态的32%、60%、36%、64%、58%、63%和43%,远高于夏季的同期水平。 2. 在不同季节,牛粪周围的土壤养分(NO3--N、NH4+-N、速效K 和无机P)含量变化随时间改变呈现相同的趋势。但是,牛粪周围不同远近下土壤养分随时间的动态变化幅度略有不同。粪下土壤养分含量随时间变化波动较大,距粪便越远,随时间变化的变幅越为平缓。总体来说,在夏季由于粪便分解较快,对土壤养分的持续作用时间不及秋季,秋季粪便分解变慢,表现出养分的缓释特征。其次,牛粪对粪下土壤影响的持续时间也长于对周围土壤的作用时间。 3. 粪便对土壤养分(NO3--N、NH4+-N、速效K、无机P)影响的范围在不同季节具有差异。夏季要高于秋季,但对周围土壤养分影响的持续时间低于秋季。在夏季短期内,牛粪对土壤NO3--N 和速效K 含量的影响范围能够超过30cm,而对NH4+-N 和无机P 的影响范围则介于10cm 和30cm 之间。在2 个月左右之后,牛粪对周围土壤养分的影响能力基本消失。在秋季,牛粪对周围土壤养分影响范围难以达到30cm 处。粪便在夏季对其下土壤和周围土壤的有机C、全N 和全P 含量并无显著影响,但在秋季能显著增加其下土壤有机C、全N 和全P 含量。 4. 牛粪在秋季对土壤SMB-C、SMB-N 和SMB-P 含量的影响能够持续2 个月以上,由于秋冬季节牛粪分解缓慢,因此推断这种效应持续时间至少能够1 年左右。另一方面,牛粪在秋季对土壤SMB-C、SMB-N 和SMB-P 含量的影响范围主要集中在其下土壤,而周围的影响效应并不明显。 The grassland on the eastern fringe of Qinghai-Tibetan Plateau was one of the four greatest pasture zones in our country and the main water conservation function zones in the hesastream of Yangtse River and Huanghe river. Rencent years, lots of dung in this area was used as biological energy, fertilizer or material of fungoid growing, leading to high risk of nutrient banlance in grassland ecosystem. In view of the researches on the impact of yak dung in this area are relatively rare, the present study focused on the relationship of dung and soil nutrient transformation in sunmer and autumn, which could profoundly illuminate the mechanism of dung decomposition and the effect of dung on soil chemical properties and soil microbe biomass. The present study also contributed to a basic understand and provided scientific management in the high-frigid ecosystem. Decomposition of yak dung and its effect on soil chemical properties in eastern grassland of Qinghai-Tibetan Plateau were determined. The study simulated the real dung pats, took dung and soil samples at different time and fixed-point in summer and autumn. The samples were analysed for NO3--N, NH4+-N, available K, inorganic P, total organic C (TOC), total N (TN), total P (TP). It was concluded that: 1. In study area, the yak dung supplied to ecosystem substantial nutrient. It is estimated that the N contribution of dung was approximately 699~932 kg ha-1, P contribution was approximately 110~147 kg ha-1. The rate of yak decomposition was more rapid in summer than autumn, the wet and dry weight of yak decreased to 14% and 24% respectively after 2 months when dung excreted in summer, with 35% and 52% in autumn. The content of NO3--N、NH4+-N、available K、inorganic P、TOC、TN and TP in dung decomposed more rapid in summer too. After 2 months when dung excreted in autumn, the content of above nutrient decreased to 32%、60%、36%、64%、58%、63% and 43% respectively,which were significantly higher than summer. 2. The content of NO3--N、NH4+-N、available K and inorganic P in soil around dung had the same transformation trend in each season, whereas it was distinguishing at different gradient of distance from dung, the nutrient in soil below dung had the most significant change while the more far from dung, the less change in soil. It was concluded that the yak dung had prolong impacts on soil in autumn compared with summer, besides, it aslo showed that the yak dung had protract effect on soil below dung compared with soil around dung. 3. The yak dung had expansive impact on soil around dung in summer whereas had relatively short effect compared with autumn. In short-term at summer, there was a significant increase about the content of NO3--N and available K around 30cm radius from dung pat while the content of NH4+-N and inorganic P between 10cm to 30cm. After 2 months, the impact almost disappeared. In autumn, the effect was hard to reach 30cm. The yak dung had no significant effects on the content of TOC、TN and TP in soil below or around dung in summer whereas there was a obvious increase in soil below dung pat in autumn. 4. The duration of effect of yak dung on soil microbial biomass(SMB) C、N and P was at least 2 months, maybe even more than 1 year. On the other hand, the impact of dung on SMB-C、SMB-N and SMB-P mainly acted on soil below dung while no obious effect on soil around dung.

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从空间、时间、食物3个方面研究了若尔盖湿地3种两栖类的种间竞争,运用生态位理论探讨了3种两栖类利用环境资源的能力以及它们之间的共存模式,研究了3种两栖类年周期食性,并考察了畜牧业对3种两栖类食性及食物竞争格局的影响;此外,还通过实验室研究对2种两栖类幼体的种间竞争策略进行了考察。主要结果如下: 1、两栖类的空间资源利用状况:在3种两栖类成体生态位宽度的比较中,岷山蟾蜍(Bufo minshanicus)成体在牧场性质(0.41)、牛粪数量(0.42)、植被盖度(0.20)、地表温度(0.50)、地表湿度(0.51) 5个维度上的生态位宽度最窄;而倭蛙(Nanorana pleskei)成体在牛粪数量(0.81)、植被高度(0.63)、植被盖度(0.47)、小水体距离(0.68) 4个维度上的生态位宽度最宽。在3种两栖类亚成体生态位宽度的比较中,岷山蟾蜍亚成体在牧场性质(0.66)、牛粪数量(0.58)、植被高度(0.64)、小水体距离(0.51)、地表湿度(0.79) 5个维度的上生态位宽度最宽;倭蛙亚成体在牧场性质(0.39)、牛粪数量(0.30)、地表温度(0.18)、地表湿度(0.33) 4个维度上的生态位宽度最窄。高原林蛙(Rana kukunoris)在地表温度(成体:0.62;亚成体:0.56)、地表湿度(成体:0.84;亚成体:0.60)两个维度上具有较大的生态位宽度值,而在小水体距离维度上(成体:0.27;亚成体:0.14)的生态位宽度值则很小。比较3种无尾两栖类在不同生长阶段(成体、亚成体)的生态位宽度,发现高原林蛙和倭蛙的亚成体对栖息环境的要求更高。3种两栖类空间资源利用的相似程度很高,高原林蛙与倭蛙之间的生态重叠度(0.87)较之它与岷山蟾蜍(0.81)的生态位重叠度更大。 2、两栖类的日活动节律:高原林蛙成体、亚成体、岷山蟾蜍亚成体活动的最低气温为0℃、2℃、8℃;岷山蟾蜍和高原林蛙亚成体出现的数量与气温成极显著的正相关(r=0.797, p<0.001;r=0.794, p<0.001),高原林蛙成体出现的数量与气温有一定相关性(r=0.456, p<0.05);晴天时两栖类的活动性明显高于阴天(p<0.001);多云转晴天气,高原林蛙和岷山蟾蜍亚成体出现两次日活动高峰,分别为中午12:30左右和下午15:30~16:30之间;多云天气,高原林蛙和岷山蟾蜍亚成体出现两次日活动高峰,分别为9:30~10:30之间和15:30~16:30之间。 3、两栖类的食物资源利用状况:春、秋两季,高原林蛙最主要的食物是蜉金龟科(Aphodiidae)昆虫,相对重要性指数(IRI)最高(春季:35.28%,秋季:28.57%),其次为昆虫的幼虫,以及双翅目的毛蚊科(Bibionidae)、蝇科(Muscidae)、丽蝇科(Calliphoridae)昆虫,秋季,蝗虫是高原林蛙食物组成中的重要部分;岷山蟾蜍最主要的食物是蚂蚁(IRI,春季:85.54%,秋季:49.70%),其次为蜉金龟科、象甲科(Curculionidae)、步甲科(Carabidae)、粪金龟科(Geotrupidae) 等鞘翅目昆虫;倭蛙春季的最主要食物也是蜉金龟科昆虫(IRI,春季:13.41%),其次为蚂蚁、毛蚊科昆虫、昆虫的幼虫以及狼蛛科(Lycosidae)。3种两栖类中,倭蛙的食性生态位宽度相对较宽(0.43),而岷山蟾蜍(0.09)和高原林蛙(0.22)的生态位宽度较窄,与春季相比,两栖类在秋季的食谱更宽。以利用食物种类为标准,春季高原林蛙与倭蛙的生态位重叠度(0.40)比它与岷山蟾蜍的生态位重叠度(0.33)更大。 4、畜牧业对两栖类食性及食物竞争格局的影响:以藏牦牛粪为食物或寄居场所的昆虫,如蜉金龟科、粪金龟科、毛蚊科、蝇科、丽蝇科昆虫和某些昆虫幼虫,是3种两栖类食物谱中最主要的组成部分,蜉金龟科昆虫在高原林蛙食谱中的比例更高,高原林蛙可能从畜牧业发展中获得更多的好处,使之在食物竞争方面处于优势地位。与无放牧样地相比,在有放牧样地的中,两栖类食谱中的蜉金龟科昆虫数量更多(有放牧:31.94%;无放牧:21.32%)、出现频率更高(有放牧:76.38%;无放牧:44%)。然而在不同样地上(有放牧/无放牧),两栖类的食物组成无显著性差异(P=0.188),两栖类的数量(P=0.075)、肥满度(P=0.537)均没有显著差别。 5、两栖类幼体的竞争策略:实验室条件下,通过活动性水平,变态时的体重、增长率和完成变态所需时间考察自然条件下常同水塘分布的中华蟾蜍(Bufo gargarizans)和高原林蛙蝌蚪的竞争策略。结果表明:中华蟾蜍蝌蚪在不同食物资源条件下,所选择的生存策略可能不同,即食物资源充足时,增加活动性获取更多食物,食物资源有限时,降低活动性且提前完成变态;与中华蟾蜍蝌蚪相比,在食物资源有限时高原林蛙蝌蚪获取食物能力可能更强。 This paper presented the study of competition of three amphibians (Rana kukunoris, Nanorana pleskei, Bufo minshanicus) based on spatial, temporal and dietary scales in Zoige wetland. We measured coexistence patterns of three amphibians and analyzed their ability of exploiting resource. Effects of grazing on the diet composition and diet competition of amphibians were analyzed by their diet composition during spring and autumn. Furthermore, we examined the competitive ability of larval common frogs (Rana kukunoris)and common toads(Bufo gargarizans) in a laboratory experiment, and analyzed their competitive strategies respectively. The results were as follows: 1 .The status of using spatial resource Niche breadths of B. minshanicus adults on 5 dimensional axes including character of pasture(0.41), number of yaks dung(0.42), vegetation coverage(0.20), temperature (0.50)and humidity(0.51) of ground surface were narrower than adults of R. kukunoris and N. pleskei. Niche breadths of B. minshanicus subadults were broader than R.kukunoris subadults and N.pleskei subadults on 5 dimensional axes including character of pasture (0.66), number of yaks dung (0.58), vegetation height (0.64), distance to small waterbodies (0.51), humidity of ground surface (0.79). Niche breadths of N. pleskei subadults were the narrowest in three anurans subadults on 4 dimensional axes including character of pasture (0.39), number of yaks dung (0.30), temperature (0.18) and humidity (0.33) of ground surface, niche breadths of N. pleskei adults were the broadest in three anurans adults on 4 dimensional axes including number of yaks dung (0.81), vegetation height (0.63) and coverage(0.47), distance to small waterbodies(0.68).Comparatively, niche breadths of R. kukunoris were broader on the two microclimate factors including temperature(adults:0.62;subadults:0.56) and humidity (adults:0.84;subadults:0.60)of ground surface, but was narrow on distance to small waterbodies(adults:0.27;subadults:0.14). Strategies for using habitat resource of adults and subadults of the three species anuran were different. Generally, subadults of R. kukunoris and N. pleskei needs better habitat condition. It was quite similar that three anurans exploited spatial resource, Niche overlap between R. kukunoris and N. pleskei (0.87) was greater than that between R. kukunoris and B.minshanicus(0.81). 2.Daily activity rhythm R. kukunoris audlts were active when air temperatures were as low as 0℃, R. kukunoris subadults were active at 2℃, B.minshanicus subaudlts were active at 8℃. Positive correlation was found between activities of amphibians and air temperature, Subadults of R.kukunoris, (r=0.797, p<0.001), Subadults,of,B.minshanicus, (r=0.794, p<0.001), andbadults,of,R.kukunoris(r=0.456, p<0.05).Amphibians were more active during sunny days than cloudy days. In cloudy turning into sunny, R. kukunoris and B.minshanicus subadults had two active peak: at noon about 12:30 and 15:30~16:30 pm; in cloudy, R. kukunoris and B.minshanicus subadult had two active peak too : 9:30~10:30am,15:30~16:30pm. 3.Diet analysis Aphodiidae was the most commonly consumed food item by R. kukunoris based on index of relative importance (IRI) during spring (35.28%) and autumn (28.57%) in Zogie wetland. Besides Aphodiidae, larval insect, dipterans such as Bibionidae, Muscidae, Calliphoridae also were important food item for R. kukunoris, in autumn, locust was one of important food item for R. kukunoris. The most important food item for B.minshanicus during spring (IRI:85.54%) and autumn (IRI:49.70%) was ants, following, was coleopterans, such as Aphodiidae, dung beetle. Aphodiidae (IRI:13.41%) were the most important consumed food item by N. pleskei during spring too, following, was ants and Bibionidae. Dietary breadth of N. pleskei (0.43) were greater than R. kukunoris (0.22) and B. minshanicus (0.09). As a whole, Dietary breadth of amphibians during aurumn were greater than spring. Based on prey item, dietary overlap between R. kukunoris and N. pleskei (0.40) was greater than that between R. kukunoris and B.minshanicus (0.33) during spring. 4.Effects of grazing on the diet composition and diet competition of amphibians Amphibians are an important part of the pasture ecosystems as prey and predator. In Zogie wetland, major diet of amphibians was closely associated with dung of yaks, for example, Aphodiidae, Bibionidae, Muscidae, dung beetle. Dung of yaks was major diet and habitat of these insects. Proportion of Aphodiidae was higher in diet composition of R. kukunoris than N. pleskei and B.minshanicus, with development of pasturage, R. kukunoris may have a diet competitive advantage over N. pleskei and B.minshanicus. Number of Aphodiidae in diet composition of amphibians was higher in samples with grazing (31.94%) than in those without grazing (21.32%). Occurrence Frequency of Aphodiidae in diet composition of amphibians was higher in samples with grazing (76.38%) than in those without grazing (44%). However, There was not significantly different on diet composition (P=0.188), and number (P=0.075) and the relative fatness (P=0.537) of amphibians between grazing samples and without grazing. 5.Competitive strategies of amphibian larvae I examined the competitive ability of larval toads (Bufo gargarizans) and frogs (Rana kukunoris) which co-occur in the nature pond by activity level, the growth rate and mass at metamorphosis and larval period in a laboratory experiment. The results suggest: In laborary, B.gargarizans adapted himself to different food level by changing activity. At high food level, B. gargarizans increased activity to gain more diet. At low food level, B. gargarizans decreased activity and achieved early metamorphosis. When food resource was limit, R. kukunoris could gain more food than B. gargarizans.

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Grazing animal excrement plays an important role in nutrient cycling and redistribution in grazing ecosystems, due to grazing in large areas and return in small areas. To elucidate the changes to the soil and pasture caused by sheep urine, fresh dung, and compost patches, a short- term field experiment using artificially placed pats was set up in the autumn of 2003 in the Inner Mongolian steppe. Urine application significantly increased soil pH during the first 32 days in soil layers at depths of both 0 - 5 cm and 5 - 15 cm. Rapid hydrolysis of urea gave large amounts of urine- nitrogen ( N) as ammonium ( NH4+) in soil extracts and was followed by apparent nitrification from day 2. Higher inorganic N content in the urine- treated soil was found throughout the experiment compared with the control. No significant effects of sheep excrement on soil microbial carbon ( C) and soil microbial N was found, but microbial activities significantly increased compared with the control after application of sheep excrement. Forty- six percent of dung- N and 27% of compost- N were transferred into vegetation after the experiment. The results from this study suggest that large amounts of nutrients have been lost from the returned excrement patches in the degraded grassland of Inner Mongolia, especially from sheep urine- N.

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Excrement patches of grazing animals play an important role in greenhouse gas (GHG) fluxes due to the high nitrogen (N) and available carbon (C) deposited in small areas, but little information is available for the effect of excrement in the Inner Mongolian grassland (43 26 degrees N, 116 degrees 40'E). To elucidate the effect of grazing sheep urine, fresh dung and compost on fluxes of methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O), a short-term field study (65 days) was carried out in the typical grassland of Inner Mongolia with the optimised closed chamber/GC technique. Compared with the control, cumulative net CH4 consumption decreased 36, 31, and 18% from urine, fresh dung, and compost plots, respectively; net CO2-C output increased by 6.5, 1.5, and 1.2% from urine, fresh dung, and compost treated soil, respectively; about three times as much N2O-N was emitted from urine and the fresh dung treatments during 65 days. Nitrous oxide emission was positively correlated with CO, emission (R = 0.691, P < 0.01) and water-filled pore space (R = 0.698, P < 0.01). The percentages of N2O-N loss of applied-N were 0.44 and 1.05% for urine and fresh dung, respectively. Our results suggest that in autumn in the degraded grassland of Inner Mongolia, the effect of sheep excrement may be ignored when evaluating the total GHG emissions.

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介绍了长焊缝激光拼焊系统的工作原理和控制要求。针对长焊缝激光拼焊的难点,提出了焊缝塑性成形原理,采用碾压轮对板材焊缝进行碾压预处理提高定位精度。阐述了牵引电机同步控制原理和碾压轮力控制原理。详细介绍了该系统的组成和工作原理,确定了以三菱PLC为核心的长焊缝激光拼焊的控制系统,说明了其硬件组成、软件设计和控制系统的抗干扰措施。

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Seismic While Drilling (SWD) is a new wellbore seismic technique. It uses the vibrations produced by a drill-bit while drilling as a downhole seismic energy source. The continuous signals generated by the drill bit are recorded by a pilot sensor attached to the top of the drill-string. Seismic wave receivers positioned in the earth near its surface receive the seismic waves both directly and reflection from the geologic formations. The pilot signal is cross-correlated with the receiver signals to compute travel-times of the arrivals (direct arrival and reflected arrival) and attenuate incoherent noise. No downhole intrusmentation is required to obtain the data and the data recording does not interfere with the drilling process. These characteristics offer a method by which borehole seismic data can be acquired, processed, and interpreted while drilling. As a Measure-While-Drill technique. SWD provides real-time seismic data for use at the well site . This can aid the engineer or driller by indicating the position of the drill-bit and providing a look at reflecting horizons yet to be encountered by the drill-bit. Furthermore, the ease with which surface receivers can be deployed makes multi-offset VSP economically feasible. First, this paper is theoretically studying drill-bit wavefield, interaction mode between drill-bit and formation below drill-bit , the new technique of modern signal process was applied to seismic data, the seismic body wave radiation pattern of a working roller-cone drill-bit can be characterized by theoretical modeling. Then , a systematical analysis about the drill-bit wave was done, time-distance equation of seismic wave traveling was established, the process of seismic while drilling was simulated using the computer software adaptive modeling of SWD was done . In order to spread this technique, I have made trial SWD modeling during drilling. the paper sketches out the procedure for trial SWD modeling during drilling , the involved instruments and their functions, and the trial effect. Subsurface condition ahead of the drill-bit can be predicted drillstring velocity was obtained by polit sensor autocorrelation. Reference decovolution, the drillstring multiples in the polit signal are removed by reference deconvolution, the crosscorrelation process enhance the signal-to-noise power ratio, lithologies. Final, SWD provides real-time seismic data for use at the well site well trajectory control exploratory well find out and preserve reservoirs. intervel velocity was computed by the traveltime The results of the interval velocity determination reflects the pore-pressure present in the subsurface units ahead of the drill-bit. the presences of fractures in subsurface formation was detected by shear wave. et al.