历史查询   



 为了更好的帮助您理解掌握查询词或其译词在地道英语中的实际用法，我们为您准备了出自英文原文的大量英语例句，供您参考。 
Zoning by Functions of SmallScale Forest Ecosystems: A Case Study of HuiSun Forest Station in Taiwan Province, China


Chinese remainder codes are the essential generalization of Sun Zi codes.


A biotechnological approach is proposed for anaerobic conservation of aerial parts of woolly foxglove, followed by airsun drying of the biologically transformed raw material.


Such a rotation is convenient in the case when it is required to secure a sufficiently uniform illumination of the satellite's surface by the Sun at a comparatively small angular velocity of the satellite.


An evaluation is also made of the correlation length of these disturbances in the plane perpendicular to the SunEarth line.

 更多 


 For use in cosmogonical investigations,a detailed calculation of the angular momenta of various bodies in the solar system is made,making use of latest data. A_(1P) denotes the orbital angular momentum of a planet about the center of mass of the sun planet system,A_(1⊙) denotes the orbital angular momentum of the sun about the same center of mass.A_(1P)+A_(1⊙)=A_1.These three quantities are calculated according to formulae (2),(3),(4), and the results are given in Table 1.In this table A_(1P) includes... For use in cosmogonical investigations,a detailed calculation of the angular momenta of various bodies in the solar system is made,making use of latest data. A_(1P) denotes the orbital angular momentum of a planet about the center of mass of the sun planet system,A_(1⊙) denotes the orbital angular momentum of the sun about the same center of mass.A_(1P)+A_(1⊙)=A_1.These three quantities are calculated according to formulae (2),(3),(4), and the results are given in Table 1.In this table A_(1P) includes the orbital angular momentum of the planet's satelfites about the center of mass of the sunplanet system.  任何有关太阳系起源的学说都必须能够说明太阳系角动量分布的特殊性,这种特殊性首先由傅歇于1884年指出来.拉普拉斯的星云假说未能说明这种特殊性.本世纪开始以来,先后提出的各种学说都注意到这个问题,但是都未能满意地说明它.最近十多年来,有关行星和卫星的各种数据有了相当多的增添和改进,恒星和行星内部结构的研究有了很大的进展,使得有可能得出太阳和各个行星的自转角动量的较可靠的数值.本工作的目的就是利用最新的数据来计算太阳系各天体的角动量,为太阳系起源问题的研究提供资料.  We treat the problem of solar activity in the long run.The data used include the semiempirical maxima and minima since 1610 A.D.The method differs from the traditional sunspot statistics in the following respects: 1.A timespot number curve using alternative positive and negative smoothed monthly mean number (R) in succesive 11year cycles is used to take the magnetic property of each cycle into account.This curve is shown in Fig.1(B) as compared to the traditional curve 1(A). 2.A number termed... We treat the problem of solar activity in the long run.The data used include the semiempirical maxima and minima since 1610 A.D.The method differs from the traditional sunspot statistics in the following respects: 1.A timespot number curve using alternative positive and negative smoothed monthly mean number (R) in succesive 11year cycles is used to take the magnetic property of each cycle into account.This curve is shown in Fig.1(B) as compared to the traditional curve 1(A). 2.A number termed the “Excitation” of the magnetic cycle E=R_(max)×T is introduced to describe the activity of each 22year cycle.R_(max) is the maximum smoothed monthly mean number (R) of the two 11year cycle belonging to this 22year magnetic cycle;T is the corresponding period.A curve showing the fluctuations of E in the course of time is shown in Fig.2. Inspection of Figs 1(B) and 2 Suggests the following possible regularities:There exists similarity between groups of successive magnetic cycles both in the [Rt] and [Et] curve. In fact,the following groups of magnetic cycles are similar:[1600]—1689.5,1689.5— 1755.2,1755.2—1823.3,1933.8—[2020] each group contains 3 or 4 magnetic cycles. The year in brackets are estimated ones.The group 1823—1933.8 is believed to be the end of a long term starting possibly from 1500.The present group which started from 1933.8 is believed to be the beginning of a new long term. With these similarity in mind,we predict the traditional 20~(th) cycle to be a major one.This agrees with the result of Minis but contradicts to those of Gleissberg and Herrinck.  本文论述了三百多年来的太阳活动的粗略规律,提出了处理本问题的另一方式,并对今后二、三十年太阳活动趋势提出了自己的看法.  The structure of the solar convection zone was calculated by E.Vitense with the mixing length theory of turbulence.A fundamental formula in her calculations is the formula for the energy flux of turbulent convection [eq.(2.1)],or W.Schmidt's formula [eq.(2.1)].This formula should be modified by the following two corrections: (1)According to the argument of S.A.Zhevakin,the specific heat at constant pressure c_p in this formula should be replaced by (1/2)C=(1/2)(C_p—A_p),where A_p is the work required for the... The structure of the solar convection zone was calculated by E.Vitense with the mixing length theory of turbulence.A fundamental formula in her calculations is the formula for the energy flux of turbulent convection [eq.(2.1)],or W.Schmidt's formula [eq.(2.1)].This formula should be modified by the following two corrections: (1)According to the argument of S.A.Zhevakin,the specific heat at constant pressure c_p in this formula should be replaced by (1/2)C=(1/2)(C_p—A_p),where A_p is the work required for the compression of one gram of medium when cooled for one degree at constant pressure.In this paper are derived the formulas of the factor C,for the hydrogen ionization zone [eq.(2.20)] and for the single ionization zone of helium [eq.(2.29)]in the envelope of a star.Eq.(2.32)is the formula for C in the critical double ionization zone of helium. (2)According to the investigation of E.J.Opik,in order to take account of the lateral exchange of heat between the turbulent elements,W.Schmidt's formula (2.1) should be multiplied by the factor f/B=0.188. The finally corrected formula is eq.(2.33).The ratio of the convective energy flux computed by eq.(2.33)to that computed by the original eq.(2.1)is 0.094C/c_p≈0.094/γ, since C is approximately equal to the specific heat at constant volume c_v and γ=c_p/c_v. This ratio is 0.0564 for ideal monatomic gas since γ=5/3 and is 0.0705 for fully ionized gas since γ=4/3.Obviously the convective energy flux computed by the original eq.(2.1) is overestimated by a factor 14—18. On the basis of the corrected formula (2.33),or(2.34),we derived anew in §4 some formulas for the calculation Of the solar convection zone as used by E.Vitense. It is obvious that E.Vitense's method and all the formulas in §§2,3 and 4 may be applied not only to the sun but also to other stars.The application to the sun is made in §5.The results are as follows: Fig.1 shows the variations of the gas pressure P_g as function of the geometrical depth t in the solar convection zone.The solid curve(——)corresponds to the model in which the mixing length l of the turbulent element is equal to H,the equivalent height of the atmosphere.The dashed curve(……)is for the model with l=2H.The thick ness of the solar convection zone with l=H is found to be 3700km and the correspon ding value of 65000kin found by E.Vitense with the original eq.(2.1)is 17.6 times overestimated.The thickness of the solar convection zone with l=2H is 8790km and the corresponding value of 160,000km found by E.Vitense is overestimated by a fac tor 18.2. Fig.2 shows the temperature T as function of the gas pressure P_g.The solid curve stands for l=H and the dashed curve for l=2H as in other figures. In Fig.3 is shown T4 as function of the mean optical depth .The dashed line with dots (—·—·—) is for the model in radiative equilibrium. Fig.4 is the entropy diagram for the layers in the solar atmosphere.The lefthand solid curve shows the outermost layer in radiative equilibrium, then begins the convection zone in two models with l=H (——) and l=2H (……),and the righthand falling parts of the curves correspond to the inner radiative layer. Fig.5 shows the ratio of πF_c to πF as function of P_g,where πF_c is the convective energy flux and πF is the total energy flux,i.e.,πF_c plus the radiative energy flux πF_rad. Therefore,it may be concluded that the thickness of the solar convection zone is some thousand kilometers in order of magnitude.  本文对经日瓦金改正过的对流能通量公式做了进一步的修改,并根据改正后的公式,重推了费坦瑟计算太阳对流层时所用的一些公式.然后计算了太阳对流层.得到的结果是:对于混合长 l 等于大气等值高度 H 的模型,对流层厚度是3700公里;对于 l =2H 的模型,对流层厚度是8790公里.   << 更多相关文摘 
相关查询  



