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1.
一、几个线性流域汇流模型流域降雨径流计算中的线性集中模型原则上都可用卷积积分来概括,即Q(t)=integral from n=0 to t≤τ_1 u(τ)α(t—τ)dτ (1)式中:t——时间;Q(t)——t 时间出口断面流量;α(t—τ)——流域面平均降雨强度(指扣除各种损失后的净雨强度,下同);u(τ)——瞬时汇流曲线;τ_1——流域汇流历时。由于对式(1)中降雨过程和流域汇流曲线所作的简化方法和近似程度不同,就形成了各种流域汇流的计算方法。下面仅举几个有代表性的加以分析:1.纳希瞬时单位线法它可由下式表示,  相似文献   

2.
以往“流速—面积”法流量测验误差的计算公式都忽略协方差项。本文分析了当考虑协方差项时,协方差项各个组成部分所处的地位,提出了考虑协方差项流量误差的计算公式,并用兰西水文站的试验资料加以验证。一、简单的回顾测量河道中的流量有各种方法,其中尤以“流速—面积”法最常用。该法测流量是通过测量垂线的水深,平均流速和间距来实现的。所以,实际上,断面流量是间接测量结果。估算一次实测流量的随机误差应通过误差传播公  相似文献   

3.
《水文》1959,(3)
文章指出,基本水量平衡公式中的蒸发量可以表示为,流域儲水量的变化則可表示为b⊿H,式中X_i—i期间的降水量,Σd_i——空气的日湿度差額总数,⊿H——断面上水位的变化,a与b——比例系数。这时,短期i的水量平衡公式可写成Xi—Yi=aX_iΣdl b⊿H。采取n水文期,就可以根据此  相似文献   

4.
一、引言经典最小二乘模型常用于一般的曲线拟合。设变量x,y有函数关系 y=f(x,β) ε (1)式中β是待定参数,ε为误差。x和β通常是向量,f是它们的线性或非线性函数。问题是给出n次观测数据(x_k,y_k),k=1,…,n,要求确定β使Q=sum from k=1 to n W_k〔y_k-f(x_k,β)〕~2→min  相似文献   

5.
供水工程     
《地下水》1991,13(1):56-58
咸水灌溉次数的计算公式咸水灌溉次数是根据“降雨淋洗值”确定的。用以下公式计算:L=sum from i=1 to n (M_iq_i C_o C_H) (1)C_H=C_o C_s (2)式中:L——降雨淋洗值,kg/亩;M_i——灌溉水含盐碱量,  相似文献   

6.
天然河道的洪水波运动,可用著名的圣维南方程组来表示,当无旁侧入流时,其形式为A/t+Q/L=0 (1)H/L=1/g·v/t+v/g·v/L+Q~2/R~2 (2)式中:A——过水断面面积;t——时间;Q——断面平均流量;L——距离;g——重力加速度;R——流量模数;v——断面平均流速;H——水位。圣维南方程组的水力学解法以瞬态法和特征线法为代表,可绘出两断面间的水面曲线,但计算工作十分繁琐,且要有详尽的河道地形资料。水文学者所需要的是由上断面的入流推算下断面出流,而两断面间的水文情势是无关紧要的。因此在忽略摩阻项和惯性项之后,以  相似文献   

7.
The composition of fluid inclusions in the H_2O-NaCl-CaCl_2 system has been generally graphically estimated using the melting temperatures of hydrohalite(T_(m-HH))and ice(T_(m-ice)).Here we present two equations that can be used to calculate the relative proportion of NaCl(i.e.,NaCl/[NaCl CaCl_2],or X_(NaCl))and the total salinity( i.e.,NaC1 CaC12,wt% )for fluid inclusions with ice as the last melting phase.X_(NaCl)can be calculated from T_(m-HH)using the following equation: y=(a bx)~(-1/c) where y is X_(NaCl),x is T_(m-HH),a=0.33124402,b=-0.031518028,and c=0.22932736.In the cases where only T_(m-ice)is measured and T_(m-HH)is not known,T_(m-ice)can be used as the maximum possible TIn.nil to calculate the maximum value of X_(NaCl)using the above equation.In these cases,the following equation can be used to calculate the maximum total salinity: y=(a bx cx~2)~(-1) where y is salinity,x is T_(m-HH),a=0.057184817,b=0.00078565757,and c=5.7262766E-6.Because the isothems in the field of ice are sub-parallel to the NaCl-CaCl_2 binary side in the H20-NaC1-CaC12 ternary system,the errors in salinity calculation introduced by the above approximation are small(less than 2 wt% ).A Windows program for calculation of X_(NsCl)and salinity is available at: http://uregina.ca/~chiguox.  相似文献   

8.
一、数学原理简述 1.水平均匀层状介质的视电阻率公式及核函数表达式: 关于公式的理论推导,在许多基础理论书籍中都可找到,在此,只列出重要的结论性公式。大家都知道,对称四极装置的视电阻率公式为: ρ_s=r~2 integral from n=0 to ∞ T_1(λ)J_1(λr)λdλ (1)其中T_1(λ)为与原参数有关的核函数,并满足如下递推式  相似文献   

9.
The Huayuan Pb-Zn ore district in China, located in western Hunan Province, is a giant carbonate-hosted Pb-Zn ore district. The source of ore-forming brines in this ore district remains poorly constrained. Whether the highly saline brines are derived from evaporated seawater or dissolved evaporates continues to be intensely debated. Carbonate minerals associated with Pb-Zn mineralization have δ13CV-PDB and δ18OV-SMOW values ranging from ?5.55‰ to +1.35‰ (mean value of ?0.69‰; n = 14) and +16.28‰ to +25.05‰ (mean value of +20.22‰; n = 14), respectively. This indicates that carbonate minerals are dominantly formed from dissolved ore-hosted carbonate rocks. The δ34S values of sulfides range from +20.2‰ to +36.8‰, with an average value of +30.0‰ (n = 27). These results suggest that sulfur is predominantly derived from the thermochemical sulfate reduction of marine sulfate. The crush-leach analyzed solute data of fluid inclusions in sphalerite show the ore-forming fluids have Cl/Br molar ratios range from 118 to 384, and Na/Br molar ratios from 39 to 160 (n = 8). These Cl/Br ratios of hydrothermal fluid are much lower than those of seawater (657 to 564), but are consistent with bittern brines through early halite precipitation. We propose that ore-forming fluids are mainly derived from evaporitic basin brines, which leached base metals from the basement and/or country rocks. The brine then migrated to the basin margins through clastic rocks of basement and then precipitated sul?des by thermochemical sulfate reduction.  相似文献   

10.
娘子关泉水流量的系统理论分析   总被引:2,自引:0,他引:2  
娘子关泉水是一个岩溶裂隙泉水,位于山西省娘子关附近。它的多年平均流量12.6立方米/秒,泉域面积3,560平方公里。娘子关泉水是中国最大的泉水之一。 泉水的数学模型可以写作: Q_t=sum from i=k to n P_(t-i)W_(i+a) 式中,Q代表泉水流量(立方米/秒);P代表降水量(毫米);W代表权系数;a代表流量误差(立方米/秒),t代表时间(年)。 利用泉水流量和降水量的观测资料,运用电子计算机,我们得到权系数:W_0=0.00364;W_1=0.00781;W_2=0.00646;W_3=0.00476;W_4=0.00522;W_5=0.00524;W_6=0.00423;W_7=0.00238;a=-0.002立方米/秒。 考虑到娘子关泉水流量与7年内的降水量关系最密切,参考区域性水文地质参数,我们计算地下水流速为10公里/年,地下水库调节库容为14立方米亿,含水层的给水度为0.0023,含水层的渗透系数为10.5米/昼夜。 另外,我们可以利用下式予报娘子关泉水流量: Q_t=0.00364P_t+0.00781P_(t-1)+0.00646P_(t-2)+0.00476P_(t-3...  相似文献   

11.
娘子关泉水流量的系统理论分析   总被引:6,自引:2,他引:4  
钱学溥 《中国岩溶》1982,1(1):10-17
娘子关泉水是一个岩溶裂隙泉水,位于山西省娘子关附近。它的多年平均流量12.6立方米/秒,泉域面积3,560平方公里。娘子关泉水是中国最大的泉水之一。 泉水的数学模型可以写作: Q_t=sum from i=k to n P_(t-i)W_(i+a) 式中,Q代表泉水流量(立方米/秒);P代表降水量(毫米);W代表权系数;a代表流量误差(立方米/秒),t代表时间(年)。 利用泉水流量和降水量的观测资料,运用电子计算机,我们得到权系数:W_0=0.00364;W_1=0.00781;W_2=0.00646;W_3=0.00476;W_4=0.00522;W_5=0.00524;W_6=0.00423;W_7=0.00238;a=-0.002立方米/秒。 考虑到娘子关泉水流量与7年内的降水量关系最密切,参考区域性水文地质参数,我们计算地下水流速为10公里/年,地下水库调节库容为14立方米亿,含水层的给水度为0.0023,含水层的渗透系数为10.5米/昼夜。 另外,我们可以利用下式予报娘子关泉水流量: Q_t=0.00364P_t+0.00781P_(t-1)+0.00646P_(t-2)+0.00476P_(t-3...   相似文献   

12.
<正>The thermo-electric coefficients of twenty-six magnetite samples,formed either by magmatism or metamorphism,were tested by the thermo-electric instrument BHET—06.Results showed that the coefficient is of a constant value of about -0.05 mV/℃.It is emphasized that because every magnetite grain was tested randomly,the coefficient is independent of the crystallographic direction.This fact means the thermal voltage generated from a single magnetite crystal can be accumulated,and as a result a new thermo-electric field can arise when a gradient thermal field exists and is active within the earth's crust.Because magnetite is widespread in the earth's crust(generally appearing more in the middle-lower crust),there is more-than-random probability that the additional thermo-electric field can be generated when certain thermal conditions are fulfilled.We,therefore,used the thermo-electric effect of magnetite to study the mechanism responsible for the presence of abnormal geo-electric fields during earthquake formation and occurrence, because gradient thermal fields always exist before earthquakes.The possible presence of additional thermo-electric fields was calculated under theoretical seismological conditions,using the following calcu-lation formula:E= - 0.159(σ×△T×φ×ρ_2×[(h~2-2x~2)cosα+ 3hxsinα]/ρ_1(h~2 +x~2)~(5/2)).In the above formula,σis thermo-electric coefficient of magnetite,△T is the temperature difference acting on it,φis a sectional area on a block of magnetite vertically perpendicular to the direction of the thermal current.ρ_1 andρ_2 are the respective resistivities of magnetite and the crust,and h,α,and x,respectively,h is the depth of embedded magnetite block,αmeans the angle created by the horizontal line and ligature of the two poles of magnetite block,and x is the distance from observation point to projective center point of the magnetite block on earth surface.According to simulations calculated with this formula,additional thermo-electric field intensity may reach as high as n to n×10~2 mV/km.This field is strong enough to cause obvious anomalies in the background geo-electric field,and can be easy probed by earthquake monitoring equipment. Therefore,we hypothesize that geo-electric abnormalities which occur during earthquakes may be caused by the thermo-electric effect of magnetite.  相似文献   

13.
在悬移质泥沙测验中,由于无法测到近底层悬移质含沙量(简称近底悬沙),因此使实际测算的输沙率(主要是床沙质部分)与真实值不符,往往相差较大。从而使年输沙量的成果精度受到影响,必须予以改正。改正年输沙量的问题,实质上是如何改正床沙质输沙率的问题。对此,以往研究较多的是解析法。由于解析法理论上不够完善,在运用该法进行计算所引用的天然河道比降,又往往不易准确观测,计算所得输沙率改正值往往误差过大,该法很难实际应用。因此,我们曾对经验法,即根据本站较精密的资料来进行改正计算作了研究,但由于如何计算概化垂线上的测点流速、含沙量与颗粒级配才能使垂线平均与断面平均  相似文献   

14.
一 “渗入系数”的基本公式是一多变量函数 根据水均衡条件简化(假定无地表水补给)处理后,得出渗入系数的公式是: α=(x-y-z)/x式中:x——年降水量(米); y——地表水年流出量(米); z——年蒸发量(米)令h=x-y则α=(h-x)/x h=αx z 上式外形为直线方程,直线斜率即“渗入系数”α,直线截矩即蒸发量z。这一计算方法把α与z认为是常量,经最小二乘法处理后,在水文地质普查中  相似文献   

15.
We present here a pilot study to examine trophic level effects and migration patterns at the middle Shang Dynasty site of Xiaoshuangqiao in Henan Province using δD results combined with δ13C and δ15N values. A total of 33 specimens (17 humans, 7 cattle, 5 pigs, 3 sheep, 1 dog) of bone collagen were isotopically analyzed for δ13C, δ15N, and dD values. A strong positive correlation (R2 = 0.94) between mean δ15N and δD values of herbivores (cattle and sheep), omnivores (pig), carnivores (dog) and humans was observed. The δD results were found to increase by ~10‰ to 20‰ from herbivores to omnivores to carnivorous, evidence that collagen δD results are a useful indicator for the study of trophic levels and dietary patterns at archaeological sites. The δD results were also used to examine the origins of two different groups of individuals buried at Xiaoshuangqiao. Individuals buried in sacrificial pits of district V had mean δD values (?47.0 ± 2.9‰, n = 11) that were significantly (p = 0.049) elevated compared to the people buried in the stratigraphy of district IX (?51.3 ± 3.3‰, n = 3), indicating that they were ingesting water from different locations. In addition, the D values of the people buried in the stratigraphy were similar to the pigs (?54.5 ± 4.2‰, n = 5) at Xiaoshuangqiao, suggesting that they were most probably of the local population, and that the individuals buried in the sacrificial pits were most possibly from the coast and prisoners of the Dongyi (“东夷”) people. Thus, δD results have the potential to examine human origins and migration patterns and should be increasingly used in conjunction with δ13C and δ15N values at archaeological sites.  相似文献   

16.
The crystal structure of lisiguangite,CuPtBiS3,from Yanshan mountains,Chengde Prefecture,Hebei Province,China has been determined by single crystal X-ray diffraction.It belongs to orthorhombic space group P2_12_12_1 with a = 7.7372(15) A,b = 12.844(3) A,c = 4.9062(10) A,V =487.57(17) A~3,Z = 4.The final full-matric least-square refinement on F2 converged with Rl = 0.0495 and wR2 = 0.0992 for 704 observed reflections[I≥2σ(I)].Lisiguangite is the isomorph of known CuNiSbS_3 and CuNiBiS_3· Pt~(2+) and Bi~(3+) have the distorted octahedral coordination enviroments composed of two metal and four S and Cu~(+2) has a distorted tetrahedral coordination environment with four S atoms.Each S atom is surrounded by four metals to give a tetrahedral environment.The crystal structure is a complex 3 dimensional network.  相似文献   

17.
We present here a pilot study to examine trophic level effects and migration patterns at the middle Shang Dynasty site of Xiaoshuangqiao in Henan Province using δD results combined with δ~(13)C and δ~(15)N values. A total of 33 specimens(17 humans, 7 cattle, 5 pigs, 3 sheep, 1 dog) of bone collagen were isotopically analyzed for δ~(13)C, δ~(15)N, and dD values. A strong positive correlation(R~2 = 0.94)between mean δ~(15)N and δD values of herbivores(cattle and sheep), omnivores(pig), carnivores(dog)and humans was observed. The δD results were found to increase by ~10‰ to 20‰ from herbivores to omnivores to carnivorous, evidence that collagen δD results are a useful indicator for the study of trophic levels and dietary patterns at archaeological sites. The δD results were also used to examine the origins of two different groups of individuals buried at Xiaoshuangqiao. Individuals buried in sacrificial pits of district V had mean δD values(-47.0 ± 2.9‰, n = 11) that were significantly(p =0.049) elevated compared to the people buried in the stratigraphy of district IX(-51.3 ± 3.3‰, n = 3),indicating that they were ingesting water from different locations. In addition, the D values of the people buried in the stratigraphy were similar to the pigs(-54.5 ± 4.2‰, n = 5) at Xiaoshuangqiao,suggesting that they were most probably of the local population, and that the individuals buried in the sacrificial pits were most possibly from the coast and prisoners of the Dongyi("东夷")people. Thus,δD results have the potential to examine human origins and migration patterns and should be increasingly used in conjunction with δ~(13)C and δ~(15)N values at archaeological sites.  相似文献   

18.
Carbonate minerals and water (or geofiuids) reactions are important for modeling of geochemical processes and have received considerable attention over the past decades. The calcite dissolution rates from 50℃ to 250℃ at 10 Mpa in deionized water with a flow rate varying from 0.2 to 5 mL/min were experimentally measured in a continuous flow column pressure vessel reactor. The dissolution began near the equilibrium with clceq > 0.3 and finally reached the equilibrium at 100℃-250℃, so the corresponding solubility was also determined as 1.87, 2.02, 2.02 and 1.88×10-4"mol/L at 100℃, 150℃, 200~C and 2500C respectively, which was first increasing and then switching to decreasing with temperature and the maximum value might occur between 150℃ and 200℃. The experimental dissolution rate not only increased with temperature, but also had a rapid increase between 150℃ and 200℃ at a constant flow rate of 4 mL/min. The measured dissolution rates can be described using rate equations of R = k(1-c/c<,eq>)<'n> or R = kc<'-n>. In these equations the reaction order n changed with temperature, which indicates that n was a variable rather than a constant, and the activation energy was 13.4 kJ/mol calculated with R = k(1-c/c<,eq>)<'n> or 18.0 kJ/mol with R = kc<'-n>, which is a little lower than the surface controlled values. The varied reaction order and lower activation energy indicates that calcite dissolution in this study is a complex interplay of diffusion controlled and surface controlled processes.  相似文献   

19.
Carbonate minerals and water (or geofluids) reactions are important for modeling of geochemical processes and have received considerable attention over the past decades.The calcite dissolution rates from 50℃to 250℃at 10 MPa in deionized water with a flow rate varying from 0.2 to 5 mL/min were experimentally measured in a continuous flow column pressure vessel reactor.The dissolution began near the equilibrium with c/c_(eq)>0.3 and finally reached the equilibrium at 100℃-250℃,so the corresponding solubility was also determined as 1.87,2.02,2.02 and 1.88×10~(-4)·mol/L at 100℃,150℃,200℃and 250℃respectively,which was first increasing and then switching to decreasing with temperature and the maximum value might occur between 150℃and 200℃.The experimental dissolution rate not only increased with temperature,but also had a rapid increase between 150℃and 200℃at a constant flow rate of 4 mL/min.The measured dissolution rates can be described using rate equations of R=k(1-c/c_(eq))n or R=kc~(-n).In these equations the reaction order n changed with temperature,which indicates that n was a variable rather than a constant,and the activation energy was 13.4 kJ/mol calculated with R=k(1-c/c_(eq))~n or 18.0 k J/mol with R=kc~(-n),which is a little lower than the surface controlled values.The varied reaction order and lower activation energy indicates that calcite dissolution in this study is a complex interplay of diffusion controlled and surface controlled processes.  相似文献   

20.
变差函数(Variogram)又称半变差函数(Semivariogram),是研究区域化变量的基本工具,记Z(x)为所研究的区域化变量(如矿石品位),γ_z为其变差函数,则变差函数的数学定义为γ_z(x,h)=1/2E{[Z(x+h)-Z(x)]~2}(1)(1)式又称为理论变差函数.按一般的统计学观点,应由下列统计基来估计γ_z,即γ_2(x,h)=1/2N sum from i=1 to N′(i/1)[Z_i(x+h)-Z_i(x)]~2(2)但是在地质问题的应用中,通常是不可能由(2)式来估计γ_z的.因为,在确定的空间位置点X_0上只能有Z(X)的一次观测值,即Z(X_0).因而,只得利用下式来估计γ_z(但这样做仍是有一定条件的).  相似文献   

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