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161.
关于飞行和游动的生物力学研究 总被引:31,自引:1,他引:30
论述了飞行和游动生物力学的任务和意义,以及重大科学问题和与仿生技术相关的重大需求,并概要地介绍了与生物外部流体力学有关的科学问题、研究现状以及我国现有的研究基础和特色.文中针对如下若干重点科学问题进行了论述,具体包括Gray疑题及鱼类阻力的测定问题、鱼类机动运动的特征和机理、鱼类游动的流-固耦合及整体模化等交叉问题、昆虫运动的非定常流动控制机理和能耗、昆虫翼的柔性变形效应及抗风机制、昆虫和鱼的自由运动的运动学和动力学测量.图0参72 相似文献
162.
圈养野生动物毛发微量元素研究 总被引:3,自引:0,他引:3
采用电感耦合等离子体发向射光谱法研究了三十种圈养野生动物毛发中12种元素的含量。对微量元素在野生动物生命过程中的作用进行了探讨。 相似文献
163.
KEVIN J. DUFFY 《Natural Resource Modeling》2011,24(1):48-60
Abstract Movement of organisms will influence their ecology and demographics. Animal movements are often characterized by path structures with directional persistence. The extent to which this impacts on population dynamics is investigated in this paper using theoretical simulations. The effects of different movement strategies on variations in visits to individual patches across a forage area are discussed. Variations in resource biomass across patches are shown to persist after long simulations. Consumer resource equations with movement are used to show how heterogeneity in resources caused by these variations can affect global population dynamics. With directional movements (random or persistent), dynamics change from limit cycles to stable equilibrium solutions. It is suggested that this effect has the potential to increase survival because perturbations from unforeseen factors (like drought) are less likely to crash populations. 相似文献
164.
We present a passive acoustic method for estimating the density of echolocating cetaceans that dive synchronously, based on isolation of dive starts using a field of distributed bottom-mounted hydrophones. The method assumes that all dive starts of the target species within a defined area are detected, and that independent estimates of dive rate and group size are available. We apply the method to estimate the density of Blainville’s beaked whales (Mesoplodon densirostris) at the Atlantic Undersea Test and Evaluation Center (AUTEC) in the Bahamas during the time of a multi-ship active sonar exercise. Estimated densities for the 65 h before the exercise, 68 h during, 65 h after, and the final 43 h monitored were 16.99 (95% CI 13.47-21.43), 4.76 (3.78-6.00), 8.67 (6.87-10.94), and 24.75 (19.62-31.23) respectively, illustrating a possible avoidance reaction. Results for the 65 h before were compared with those from the click count density estimation algorithm developed by Marques et al. [Marques T, Thomas L, Ward J, DiMarzio N, Tyack P. Estimating cetacean population density using fixed passive acoustic sensors. An example with Blainville’s beaked whales. J Acoust Soc Am 2009;125(4):1982-1994]. The click count-based estimate was 19.23 animals/1000 km2 (95% CI 12.69-29.13)—similar (13% higher), but with higher variance (CV 21% for click count method versus 12% for the dive count method). We discuss potential reasons for the differences, and compare the utility of the two methods. For both, obtaining reliable estimates of the factors that scale the measured quantity (dive starts or detected clicks) to density is the key hurdle. Defining the area monitored in the dive count method can also be problematic, particularly if the array is small. 相似文献
165.
以猪肉、猪肝、猪肾、胖头鱼、对虾和蟹为试验材料,建立了喹乙醇(OLA)的残留标示物3-甲基喹恶啉-2-羧酸(MQCA)残留的超高效液相色谱-串联质谱(UPLC-MS/MS)检测方法。采用0.2 mol/L盐酸提取可食性组织中的分析物,经C18固相萃取小柱净化、35 ℃氮气吹干及含0.1%(v/v)甲酸的乙腈溶解后,采用超高效液相色谱分离,串联质谱法确证和定量分析。质谱检测采取正离子多反应监测模式,外标法定量。结果表明: MQCA在2~500 μg/L范围内呈良好的线性关系,各组织中的相关系数(r2)均大于0.990;猪肉、猪肝、猪肾、鱼、对虾和蟹中MQCA的检出限依次为0.90、1.51、0.94、1.04、1.62和1.80 μg/kg,定量限依次为3.00、5.02、3.13、3.46、5.40、6.00 μg/kg。从3~100 μg/kg的添加浓度的检测结果可以看出,MQCA的平均回收率均在73.6%与89.0%之间,日内相对标准偏差(RSD, n=5)在15%以下,日间RSD(n=3)为20%以下。该方法的灵敏度、准确度和精密度均符合兽药残留分析技术的要求,适用于动物组织中MQCA残留的定量分析和确证检测。 相似文献
166.
动物组织中硝呋索尔代谢物残留量的液相色谱串联质谱法测定 总被引:2,自引:0,他引:2
建立了动物组织中硝呋索尔代谢物二硝基水杨酸肼(DNSAH)残留量的高效液相色谱-串联质谱检测方法(HPLC-MS/MS).动物组织中的硝呋索尔代谢物在酸性条件下水解过夜,同时加入2-硝基苯甲醛进行衍生化反应,经乙酸乙酯提取浓缩,正己烷净化后.采用Thermo Hypersil Gold C18(100 mm ×2.1 mm i.d.,1.9 μm)反相色谱柱进行分离,以甲醇-水为流动相,梯度洗脱,流速为0.3 mL/min,用高效液相色谱-串联质谱仪以负离子多反应监测模式测定.结果显示,在动物组织中,DNSAH的定量下限为0.5μg/kg;线性范围为0.5~ 5.0 μg/kg,加标回收率为91%~103%,相对标准偏差为3.7%~13.6%.该方法简便、快速、准确,各项技术指标满足国内外法规的要求,适用于动物组织中硝呋索尔代谢物残留量的确证与检测. 相似文献
167.
用原子荧光法测定了动物性食品中的无机砷。结果表明,与国标法测定结果对比,检测结果准确可靠,能缩短水浴时间,试样通过轻度震摇,浸提更充分。该法对于动物源性食品的无机砷的测定更简便、快速、准确,适合动物源性食品的质量控制。 相似文献
168.
169.
Modern methods of recycling organic waste are not considered viable today. Therefore, an important advantage of the proposed technology is to obtain mineral fuel products as an output. The technologies of high-temperature processing are based on thermal decomposition of waste without oxygen at high temperature. In pyrolysis, wastes are converted into gaseous, liquid and solid fuels. Thereby, the properties and composition of the liquid feedstock obtained by pyrolysis with a boiling temperature in the range of X.I. (38) - 180 °C, 180 - 320 °C and more than 320 °C were investigated. Residue with a boiling temperature over 320° C (52.4% vol.) is the main portion of the synthetic liquid fuels (SLF). It can be attributed to fuel oil grade 100 and used as boiler fuel or fuel oil additives according to the studied physicochemical parameters. 相似文献
170.
A selective and sensitive isotope dilution–high performance liquid chromatography–linear ion trap mass spectrometry (Isotope Dilution–HPLC–LIT-MS3) method was developed for the simultaneous determination of 19 triazine pesticides and their degradation products in processed cereal samples from Chinese total diet study (TDS). The method integrated the addition of isotope internal standards, liquid–liquid extraction (LLE), clean-up with MCX solid-phase extraction (SPE) cartridges and HPLC–LIT-MS3 analysis with selected reaction monitoring (SRM) mode. Matrix-matched calibration curves showed good linearity (R2 ≥ 0.9940) verified by applying the Mandel's fitting test (p > 0.087) performed at the 95% confidence level. Decision limits (CCαs) and detection capabilities (CCβs) of the 19 triazine pesticides and their degradation products fell in the ranges of 0.0020–0.4200 μg kg−1 and 0.0024–0.4500 μg kg−1, respectively. Recoveries ranged from 70.1% to 112.8%, with the relative standard deviations (RSDs) ranging from 1.5% to 13.5%. Furthermore, the proposed method was applied to analyzing the proposed cereal samples from the fourth Chinese TDS. Eleven triazines were detected in six cereal samples with the concentrations ranging from 0.013 to 0.987 μg kg−1. This method can also be used for the further determination of the triazines in other food group composites, and ultimately served as a methodological foundation for assessing the triazines in the average Chinese diet in the general population. 相似文献