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鳙鱼的鱼体生化组成及比能值研究
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作者 姜碧薇 《农村经济与科技》 2017年第16期41-42,共2页
鱼体的能量密度即单位重量鱼体所含的能量值,它是衡量鱼类身体能量储备水平的一个重要指标。本文对宁夏沙湖的鳙鱼(大花鲢)的生化组成及比能值进行了研究。通过实际测量鳙鱼的蛋白质含量、脂肪含量、粗灰分含量、水分含量及鱼体比能值... 鱼体的能量密度即单位重量鱼体所含的能量值,它是衡量鱼类身体能量储备水平的一个重要指标。本文对宁夏沙湖的鳙鱼(大花鲢)的生化组成及比能值进行了研究。通过实际测量鳙鱼的蛋白质含量、脂肪含量、粗灰分含量、水分含量及鱼体比能值的测定与研究,结果表明,粗灰分含量与水分含量和实测比能值存在不显著相关(P>0.05),粗蛋白含量与水分含量和比能值存在显著相关(P<0.05),粗脂肪含量与水分含量和比能值存在极显著相关(P<0.01)。干物质含量和比能值存在极显著相关(P<0.01)。各生化组成和比能值与鱼体的鲜重和全长都存在不显著相关(P>0.05)。因此,水分含量可以用来间接估算鳙鱼鱼体的生化组成和比能值,进而用于野外鱼类能量学和生态系统能流分析的研究。 展开更多
关键词 鳙鱼 生化组成 比能(能量密度)
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晋冀蒙交界地区地震危险性评估及地震活动性分析 被引量:1
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作者 孙丽娜 杨锐 +1 位作者 王晓山 陈婷 《震灾防御技术》 CSCD 北大核心 2020年第1期143-155,共13页
本文利用晋冀蒙交界地区1500年以来记录较完整的MS5.0及以上历史地震烈度资料和2000年以来的地震活动资料,分别进行地震灾害危险性和地震活动性分析。首先,利用ArcGIS将历史地震烈度资料数字化,没有等震线记录的地震用烈度衰减关系计算... 本文利用晋冀蒙交界地区1500年以来记录较完整的MS5.0及以上历史地震烈度资料和2000年以来的地震活动资料,分别进行地震灾害危险性和地震活动性分析。首先,利用ArcGIS将历史地震烈度资料数字化,没有等震线记录的地震用烈度衰减关系计算烈度圈半径。将研究区划分成0.1°×0.1°的网格,将烈度资料分配到与之相交的每个网格,并用烈度-频度关系计算每个网格的烈度a、b值。基于地震发生遵从泊松分布的假定,估算未来50年内晋冀蒙交界区遭受某一地震烈度的超越概率。同时,计算50年超越概率10%对应的地震烈度,计算结果表明张家口蔚县、阳原和山西广灵县周边地区的地震危险性较高。最后,采用中小地震能量密度值计算方法,对2000年以来的现今地震活动进行定量分析,与历史地震烈度资料分析结果进行对比,发现中小地震活动圈定的危险区与历史地震烈度资料评估计算的概率高值区相对应,因此,这两种方法可为晋冀蒙交界地区的地震活动性和危险性评价提供参考。 展开更多
关键词 地震烈度 等震线 地震危险性评估 中小地震 定量分析 能量密度值
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中小地震定量分析在地震区带划分中的应用——以龙门山地震带及邻区为例 被引量:6
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作者 谢卓娟 吕悦军 张力方 《西北地震学报》 CSCD 北大核心 2012年第3期277-283,共7页
采用中小地震能量密度值计算方法,定量分析龙门山地震带及邻区1970年以来现代中小地震空间分布图像特征,探讨其与历史强震震中分布、主要断裂展布和地震带边界的关系,验证了新区划图中龙门山地震带边界修改方案的合理性。同时基于震级-... 采用中小地震能量密度值计算方法,定量分析龙门山地震带及邻区1970年以来现代中小地震空间分布图像特征,探讨其与历史强震震中分布、主要断裂展布和地震带边界的关系,验证了新区划图中龙门山地震带边界修改方案的合理性。同时基于震级-频度分布原理,对所使用的中小地震资料进行完整性分析,分别给出了区域内不同时段的最小完整性震级MC。本研究为此地区地震区、带划分提供了定量依据,可供地震活动性分析和地震危险性评价研究时参考。 展开更多
关键词 中小地震 定量分析 龙门山地震带 最小完整性震级Mc 能量密度值
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基于PET的ITO薄膜激光刻蚀研究
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作者 黄健 周苏 《佳木斯大学学报(自然科学版)》 CAS 2012年第4期536-539,共4页
使用波长为1064纳米的皮秒激光脉冲从前后两侧对PET基体上的ITO薄膜进行刻蚀.通过拉曼光谱仪得到光斑的直径找出焦点并计算该处的光束直径与阀值能量密度.而依据白光干涉显微镜得到光斑的深度可以估算能使ITO薄膜完全移除但PET基体不被... 使用波长为1064纳米的皮秒激光脉冲从前后两侧对PET基体上的ITO薄膜进行刻蚀.通过拉曼光谱仪得到光斑的直径找出焦点并计算该处的光束直径与阀值能量密度.而依据白光干涉显微镜得到光斑的深度可以估算能使ITO薄膜完全移除但PET基体不被破坏的能量密度窗口.实验结果表明,前侧相比后侧具有更小的阀值能量密度和更大的能量密度窗口. 展开更多
关键词 ITO PET 皮秒激光 能量密度 能量密度窗口
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The Study of Changes in the Element Compositions of Pd and Re Specimens Irradiated in Dense Gaseous Deuterium by y-Quanta with Boundary Energy up to 23 MeV 被引量:2
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作者 Alexander Yurievich Didyk Roland Stanislaw Wisniewski 《Journal of Physical Science and Application》 2013年第4期209-216,共8页
The element compositions of palladium and rhenium specimens irradiated in dense gaseous deuterium by y-quanta with the threshold energy 23 MeV were studies. Strong anomalies are found in the structure and element comp... The element compositions of palladium and rhenium specimens irradiated in dense gaseous deuterium by y-quanta with the threshold energy 23 MeV were studies. Strong anomalies are found in the structure and element composition of the irradiated Pd and Re specimens. 展开更多
关键词 25.45.-z 2H-induced reactions 25.45.De elastic and inelastic 25.20Dc photon absorption and scattering.
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A Modified Earthquake Model of Self-Organized Criticality on Small World Networks 被引量:1
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作者 LINMin ZHAOXiao-Wei CHENTian-Lun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第4期557-560,共4页
A modified Olami Feder-Christensen model of self-organized criticality on a square lattice with the properties of small world networks has been studied.We find that our model displays power-law behavior and the expone... A modified Olami Feder-Christensen model of self-organized criticality on a square lattice with the properties of small world networks has been studied.We find that our model displays power-law behavior and the exponent τ of the model depends on φ,the density of long-range connections in our network. 展开更多
关键词 self-organized criticality AVALANCHE small world networks
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Approximate w_φ~Ω_φ Relations in Quintessence Models
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作者 罗民兴 苏奇平 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第7期186-190,共5页
Quintessence field is a widely-studied candidate of dark energy. There is "tracker solution" in quintessence models, in which evolution of the field φ at present times is not sensitive to its initial conditions. Wh... Quintessence field is a widely-studied candidate of dark energy. There is "tracker solution" in quintessence models, in which evolution of the field φ at present times is not sensitive to its initial conditions. When the energy density of dark energy is negleetable (Ωφ 〈〈 1), evolution of the tracker solution can be well analysed from "tracker equation". In this paper, we try to study evolution of the quintessence field from "full tracker equation", which is valid for all spans of Ωφ. We get stable fixed points of we and wφ (noted as wφ and Ωφ) from the "full tracker equation", i.e., we and ωφ will always approach ωφ and Ωφ respectively. Since wφ and Ωφ are analytic functions of φ, analytic relation of φ can be obtained, which is a good approximation for the we φ relation and can be obtained for the most type of quintessence potentials. By using this approximation, we find that inequalities ωφ 〈 we and 〈ωφ are statisfied if the we (or ωφ) decreases with time. In this way, the potentiai U(φ) can be constrained directly from observations, by no need of solving the equations of motion numerically. 展开更多
关键词 QUINTESSENCE tracker equation APPROXIMATION
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Research on Energy Value of Dynamic Energy Budget 被引量:1
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作者 LIU Dan Guan Weibina 《International Journal of Technology Management》 2014年第9期145-148,共4页
Dynamic Energy Budget software aims to identify simple quantitative rules for the organization of metabolism of individual organisms. It is always used to delineate reserves, as separate from structure. The energy den... Dynamic Energy Budget software aims to identify simple quantitative rules for the organization of metabolism of individual organisms. It is always used to delineate reserves, as separate from structure. The energy density of Eriocheir sinensis was studied through DEB software in this paper. The results showed that Hepatopancreas energy density (32.17 ± 3.77 KJ/g) was higher than gonad (23.19 ± 2.86KJ/ g), muscle (24.41± 1.41 K J/g) and carapace energy density (14.42 ±1.76 KJ/g). The difference between gonad (23.19± 2.86KJ/g) and muscle energy density (4.41 ±1.41 K J/g) of females and males was significant (P 〈 0.01), but not between muscle and carapace energy density (P 〉 0.05), and no difference between female and male individual in total energy (P = 0.887) at the stable stage. The linear relation between volume and weight of Eriocheir sinensis was gained by using regression analysis, V=6.104+ 1.117WW (R2=0.973, n=98), and the linear relation between total energy and dry weight was also gained, E= 18.12DW-28.05 (R2=0.962 ,n=24). 展开更多
关键词 energy density energy allocation dynamic energy budget Eriocheir sinensis
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Energy Transfer among Modes in a Non-Slender Elastic Beam Subject to Vortex-Induced Vibration
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作者 Miguel A. Barron Dulce Medina Isaias Hilerio 《Computer Technology and Application》 2013年第5期266-270,共5页
The vibration of an elastic beam experiencing vortex-induced vibration is numerically analyzed employing a wake-oscillator model. The influence of the excited mode, the initial velocity, the shedding pulsation and the... The vibration of an elastic beam experiencing vortex-induced vibration is numerically analyzed employing a wake-oscillator model. The influence of the excited mode, the initial velocity, the shedding pulsation and the mass ratio on the energy transfer among modes and the vibration amplitude is determined. Multiple frequencies are detected, and the power spectral density of the beam tip time series is used to calculate the dominant frequency. 展开更多
关键词 Elastic beam energy transfer fluid-structure problem power spectral density vibration modes vortex-induced vibration wake-oscillator model.
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Strain Effect on the Absorption Threshold Energy of Silicon Circular Nanowires
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作者 R.Khordad H.Bahramiyan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第1期87-91,共5页
In this work,the influence of strain on threshold energy of absorption in Silicon circular nanowires is investigated.For this purpose,we first have used the density functional theory(DFT) to calculate the electron and... In this work,the influence of strain on threshold energy of absorption in Silicon circular nanowires is investigated.For this purpose,we first have used the density functional theory(DFT) to calculate the electron and hole effective masses.Then,we have obtained absorption threshold energy with two different procedures,DFT and effective mass approximation(EMA).We have also obtained the band structures of Si nanowires both DFT and EMA.The results show that:i) the expansive strain increases the hole effective mass while compressive strain increases the electron effective mass,ii) the electron and hole effective masses reduce with decreasing the wire size,iii) the absorption threshold energy decreases by increasing strain for compressive and tensile strain and its behavior as a function of strain is approximately parabolic,iv) the absorption threshold energy(for all sizes) obtained using EMA is greater than the DFT results. 展开更多
关键词 quantum wire ab initio calculations optical properties mechanical properties
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