查询词典 mean density

Density Functional Theory method was used to optimize the geometries of 209 PCDE molecules, 209 PBDE molecules and 75 PCDD molecules at the B3LYP/6-31G* level. Using computed structural parameters as theoretical descriptors, the forward stepwise multiple regression technique was adopted to obtain QSPR models of environmental partition properties for these POPs by using GQSARF 2.0 and SPSS12.0 for windows programs. The obtained QSPR models are as follows:(1) QSPR models for predicting subcooled liquid vapor pressure, n-octanol/water partition coefficients lgK_(ow and subcooled liquid water solubilities -lgS_(w,l of PCDEs, of which correlative coefficients (R~2) are 0.988, 0.958 and 0.959 and the root-mean-square-error of estimation are 0.134, 0.116 and 0.327 respectively.(2) QSPR models of lgPL and n-octanol/air partition coefficients lgK_(oa for PBDEs, which both contain three structural parameters. The values of R2 for the two models are both 0.997 while the values of RMSEE are 0.073 and 0.062 respectively.(3) QSPR models of lgKow and–lgS_ for PCDEs, which both have one variable (mean molecular polarizability,α). The values of R~2 for the two models are 0.978 and 0.866 and the values of RMSEE are 0.300 and 0.270 respectively.(4) The molecular structures of 24 substituted naphthaline compounds were optimized using Hartree-Fock and DFT methods at four different levels and the same means was used to obtain four three-parameter (EHOMO, q~+ andα) QSPR models of lgK_. The model at the HF/6-311G** level is the best one of which R2 is 0.9662 and RMSEE is 0.380.(5) QSPR study for environmental partition properties of PCDEs was also performed using position of Cl substitution method in which simple parameters of substitution position were taken as descriptors. The multiple linear regression was performed with GQSARF 2.0 and SSPS 12.0 for windows programs to obtain QSPR models of lgP_L, lgK_ and–lgS_ for PCDEs of which R~2 are 0.991, 0.983 and 0.965 and RMSEE are 0.311, 0.100 and 0.300 respectively.

采用密度泛函理论方法在B3LYP/6-31G*水平上对PCDEs、PBDEs和PCDDs的分子结构进行了全优化计算，以计算得到的量子化学参数作为理论描述符，采用GQSARF 2.0和SPSS 12.0 for windows统计程序进行正向逐步回归分析，建立了这些POPs的环境分配性质的QSPR模型：(1) PCDEs的过冷液体蒸汽压、正辛醇/水分配系数lgK_(ow和水溶解度-lgS_(w，l的QSPR模型，这3个QSPR模型的相关系数(R2)分别为0.988、0.958和0.959，估计的均方根误差分别为0.134、0.116和0.327；(2) PBDEs的lgPL和正辛醇/空气分配系数lgK_(oa的QSPR模型，这两个模型都包含三个分子结构参数，其R~2都为0.997，RSMEE分别为0.073和0.062；(3) PCDDs类化合物的lgK_和-lgS_w的QSPR模型，两个模型都只含一个变量，其R~2分别为0.978和0.866，RSMEE分别为0.300和0.270；(4)采用Hartree-Fock和DFT方法，在4种不同水平上优化计算了24个取代萘系列化合物的分子结构，采用上述同样的方法分别建立了四种水平上的三变量lgK_模型，通过比较得到，在HF/6-311G**水平计算得到的模型最好，R为0.966，RSMEE为0.380；(5)同时，采用氯原子取代位置方法对PCDEs的环境分配性质进行QSPR研究，建立了PCDEs的lgPL、lgK_和-lgS_的QSPR模型，其R~2分别为0.991、0.983和0.965，RSMEE分别为0.110、0.100和0.300。

In this study, with a total of 798 SOC density data and the 1:500 000 soil maps, the SOC storage in YunnanGuizhouGuangxi Region of China (including Yunnan province, Guizhou province and Guangxi Zhuang Autonomous Region) was estimated using the soil type method with the linkage of arithmetic mean method, median method, and areaweighted mean method (based on the area recorded in the Soil Series) based on different map units and the results were compared with that of the linkage of PKB method (Pedological Professional Knowledge Based Method).

利用中国滇黔桂地区（云南省、贵州省和广西壮族自治区）798个土壤剖面及1∶[KG-*2]50万土壤图在不同的制图单元水平上，分别采用算术平均值法、中值法和面积加权平均值法（以土种志中的面积为权重）估算了该地区1 m深度SOC储量，并与基于土壤学专业知识连接方法（Pedological Knowledge Based Method， PKB）的估算结果进行了比较。

In this study, with a total of 798 SOC density data and the 1:500 000 soil maps, the SOC storage in Yunnan-Guizhou-Guangxi Region of China (including Yunnan province, Guizhou province and Guangxi Zhuang Autonomous Region) was estimated using the soil type method with the soil type method with the linkage of arithmetic mean method, median method, and area-weighted mean method (based on the area recorded in the Soil Series) based on different map units and the results were compared with that of the linkage of PKB method (Pedological Professional Knowledge Based Method).

利用中国滇黔桂地区（云南省、贵州省和广西壮族自治区）798个土壤剖面及1：50万土壤图在不同的制图单元水平上，分别采用算术平均值法、中值法和面积加权平均值法（以土种志中的面积为权重）估算了该地区1 m深度SOC储量，并与基于土壤学专业知识连接方法(Pedological Knowledge Based Method，PKB)的估算结果进行了比较。

Based on the famous -3/2 power rule, the equations were established on the relationship between density of stand and the mean diameter, mean basal area of individual and total basal area of stands in the process of the self-thinning of Pinus taiwanensis natural forest.

应用-3/2法则，建立黄山松天然林自然稀疏过程中林分密度与平均直径、平均木断面积、总断面积的相关关系。

When we say that the War of Resistance Against Japan is progressive, we do not mean progressive in the ordinary or general sense, nor do we mean progressive in the sense that the Abyssinian war against Italy, or the Taiping Revolution or the Revolution of 1911 were progressive, we mean progressive in the sense that China is progressive today.

所谓抗日战争是进步的，不是说普通一般的进步，不是说阿比西尼亚抗意战争的那种进步，也不是说太平天国或辛亥革命的那种进步，而是说今天中国的进步。

By the budgetary estimate of the water and heat conditions at the glacial equilibrium line and the water balance of lakes in the area of the West Kunlun Mountains during the late stadial of the Last Glaciation. before the summer mean temperature decreased by 1.5 C, the annal mean precipitation was 10-20% more than that of the present. As the summer mean temperature lowering was over 1. 5 C, the precipitation was decreased and the negtive of the lake water balance appeared.

文中还根据对西昆仑山区冰川零平衡线处水热状况及湖泊水量平衡状况的推算，指出末次盛冰期中，在夏季温度降低1-1.5℃以前，其年降水量应大于现代值，增加量大约在10-20％左右；在夏季温度降低值大于1-1.5℃以后，其降水减少，湖泊水量平衡出现负值，这与冰川、湖泊变化的地质记录所反映的早期冷湿、中期冷干气候条件相符。

Uses the arithmetic mean of the mean peak force and the mean valley force.

4使用算术平均的平均峰值力及平均谷武力。

And use frequency formula or weighted harmonic mean formula of weighted arithmetic mean formula to get its mean value.

利用加权算数平均数的频数公式或加权调和平均数公式求其平均值。

Auntie, I know now it was mean, but I didn't mean to be mean.

你知道我们当时是多么伤心吗？""

This indicates the volcanic rocks with the character of autunite alkalescence siries, LREE/HREE=4.31-14.60, with a mean value of 8.74,=3.72-16.16, with a mean value of 9.59, enrichment of LREE,δEu=0.61-1.11, with a mean value of 0.80, majority samples δEu.0, indicate Eu pronounced weak negative abnormalty or no pronounced Eu abnormally.

LREE/HREE=4.31~14.60，平均8.74，=3.72~16.16，平均9.59，具有LREE富集的特征，δEu=0.61~1.11，平均0.80，多数样品δEu.0，表明铕呈弱负异常或不显异常。

This paper designs the communication system of radio telescope FAST.

针对500m口径球面射电望远镜FAST分布式控制系统的特点完成了其通信系统的设计。

Political sheep's step-by-step a large number of fossils unearthed in the county soil Ma Ali after rural village in the middle of sallow pelitic siltstone.

步氏和政羊化石大量出土于广河县阿力麻土乡后山村，产于灰黄色泥质粉砂岩中。