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101.
研究了宁波地区海域2011年3月、5月、8月、10月的排污口污水水体中可培养细菌的数量、组成及其分布, 探讨了优势菌群与当地环境的相关关系. 结果表明: 各地区细菌分布各月份性差异明显, 5月份、8月份细菌数量明显高于3月与10月, 其均值数量级能达到106 cfu?mL-1; 象山、余姚地区排污口细菌数量高于奉化、宁海、北仑地区, 细菌数量最高均值为8月份象山地区排污口(4.7×106cfu?mL-1). 优势菌群分布具有季节性分布特征: 3月份特有优势菌群为假单胞菌属(Pseudomonas sp.)与海单胞菌属(Marinomonas sp.); 5月份为假单胞菌属(Pseudomonas sp.)、海单胞菌属(Marinomonas sp.)与弧菌属(Vibrio sp.); 8月份为泛菌属(Pantoea sp.)、弧菌属(Vibrio sp.)、肠杆菌属(Enterobacter sp.); 10月份为不动杆菌属(Acinetobacter sp.)、弧菌属(Vibrio sp.)、希瓦氏菌属(Shewanella sp.). 多维尺度分析表明: 临近海域类型与排污口类型为排污口细菌群落变化的两个关键因素. 相似文献
102.
The H-matrices are an important class in the matrix theory, and have many applications. Recently, this concept has been extended to higher order ?-tensors. In this paper, we establish important properties of diagonally dominant tensors and ?-tensors. Distributions of eigenvalues of nonsingular symmetric ?-tensors are given. An ?+-tensor is semi-positive, which enlarges the area of semi-positive tensor from ?-tensor to ?+-tensor. The spectral radius of Jacobi tensor of a nonsingular (resp. singular) ?-tensor is less than (resp. equal to) one. In particular, we show that a quasi-diagonally dominant tensor is a nonsingular ?-tensor if and only if all of its principal sub-tensors are nonsingular ?-tensors. An irreducible tensor A is an ?-tensor if and only if it is quasi-diagonally dominant. 相似文献
103.
In both the scalar quasi-massless SUSY breaking scenario and dilaton-dominant SUSY breaking scenario, we analyze experimental constraints to the parameter space in M theory compactified on S1/Z2. The sparticle spectrum and some phenomenological predictions are given. 相似文献
104.
A nonlinear ALE‐FCT scheme for non‐equilibrium reactive solute transport in moving domains 下载免费PDF全文
In this paper, we present a conservative, positivity‐preserving, high‐resolution nonlinear ALE‐flux‐corrected transport (FCT) scheme for reactive transport models in moving domains. The mathematical model is a convection–diffusion equation with a nonlinear flux equation on the moving channel wall. The reactive transport is assumed to have dominant Péclet and Damköhler numbers, a phenomenon that often results in non‐physical negative solutions. The scheme presented here is proven to be mass conservative in time and positive at all times for a small enough Δt. Reactive transport examples are simulated using this scheme for its validation, to show its convergence, and to compare it against the linear ALE‐FCT scheme. The nonlinear ALE‐FCT is shown to perform better than the linear ALE‐FCT schemes for large time steps. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
105.
从理论上推导出了加筋土强度的数学表达式,分析了土的黏聚力与土筋界面参数变化对加筋土强度的影响,研究表明,当发生拉断型破坏时,黏聚力的减少比筋材提供的拉力占优势的情况下,加筋土的强度会低于素土的强度;当发生黏着型破坏时,黏聚力的减少比筋材提供的摩阻力占优势的情况下,加筋土的强度也会低于素土的强度。加筋土强度的降低程度与筋材在土中形成的夹层、土筋界面透水性、加筋间距有关。 相似文献
106.
107.
The purpose of the present paper is to obtain some sandwich-type theorems, which are combined by subordination and superordination preserving properties associated with a certain family of multiplier transformations for meromorphic multivalent functions in the punctured open unit disk. 相似文献
108.
109.
This paper considers the pricing decisions and two-tier advertising levels between one manufacturer and one retailer where customer demand depends on the retail price and advertisement by a manufacturer and a retailer. We solve a Stackelberg game with the manufacturer as the leader and the retailer as the follower. With price sensitive customer demand and a linear wholesale contract, we obtain the optimal decisions by the manufacturer and the optimal responses by the retailer. Our results show that cost sharing of local advertising does not work well, it is better for the manufacturer to advertise nationally and offer the retailer a lower wholesale price. 相似文献
110.