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71.
Modeling for fast calculation of fluid flow ensembles based on time relaxation regularization is studied herein. At each time step, the proposed model requires the storage of a single coefficient matrix with multiple right‐hands sides, corresponding to each ensemble member. The time relaxation regularization penalizes the deviation of the fluctuations from the ensemble average. The algorithm is shown to be stable under a time step restriction, which holds provided fluctuations are small enough. Also, the numerical tests show that a grad‐div stabilization weakened the condition considerably. Finite element convergence results for the time relaxation ensemble algorithm are studied too. Then, 2D and 3D numerical experiments that support the theoretical results are presented. © 2015 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 32: 757–777, 2016  相似文献   
72.
A novel supramolecular solvent‐based microextraction followed by high‐performance liquid chromatography with ultraviolet detection method has been developed for the extraction and determination of two pyrethroid analytes, cyhalothrin and fenvalerate, in water and soil samples. The liquid–liquid‐phase separation of surfactants has been used in analytical extraction. The surfactant‐rich phase is a nano‐structured liquid, recently named as a supramolecular solvent, generated from the amphiphiles. The alkyl carboxylic acid based supramolecular solvents were introduced before. Coacervates made up of gemini surfactant, consisting of two amphiphilic moieties, were first used as solvent. The effective parameters on extraction (i.e., type of organic solvent, the amount of surfactant and volume of tetrahydrofuran, sample solution pH, salt addition, ultrasonic and centrifugation time) were investigated and optimized. Under the optimum conditions, preconcentration factors of 110 and 145 were obtained for the analytes. The linearity was 0.5–200.0 μg/L with the correlation of determination of (R2) ≥ 0.9984. The limit of detection of the method was (S/N = 3) 0.2 μg/L, and precisions in the range of 6.3–10.3% (RSDs, n = 5) were obtained. This method has been successfully applied to analyze real samples, and good recoveries in the range of 101.2–108.8% were obtained.  相似文献   
73.
Over the past decade, there have been remarkable advances in understanding the signaling pathways involved in cancer development. It is well-established that cancer is caused by the dysregulation of cellular pathways involved in proliferation, cell cycle, apoptosis, cell metabolism, migration, cell polarity, and differentiation. Besides, growing evidence indicates that extracellular matrix signaling, cell surface proteoglycans, and angiogenesis can contribute to cancer development. Given the genetic instability and vast intra-tumoral heterogeneity revealed by the single-cell sequencing of tumoral cells, the current approaches cannot eliminate the mutating cancer cells. Besides, the polyclonal expansion of tumor-infiltrated lymphocytes in response to tumoral neoantigens cannot elicit anti-tumoral immune responses due to the immunosuppressive tumor microenvironment. Nevertheless, the data from the single-cell sequencing of immune cells can provide valuable insights regarding the expression of inhibitory immune checkpoints/related signaling factors in immune cells, which can be used to select immune checkpoint inhibitors and adjust their dosage. Indeed, the integration of the data obtained from the single-cell sequencing of immune cells with immune checkpoint inhibitors can increase the response rate of immune checkpoint inhibitors, decrease the immune-related adverse events, and facilitate tumoral cell elimination. This study aims to review key pathways involved in tumor development and shed light on single-cell sequencing. It also intends to address the shortcomings of immune checkpoint inhibitors, i.e., their varied response rates among cancer patients and increased risk of autoimmunity development, via applying the data from the single-cell sequencing of immune cells.  相似文献   
74.
利用粘度碰撞积分方程的直接反演方法计算了两个二元气体混合体系即苯-甲醇和甲烷-四氟甲烷的低密度势能.另外利用动力学理论以及对应态原理计算了两种体系不同温度和不同比例的粘度系数和扩散系数.计算结果和实验数据具有较好的一致性.  相似文献   
75.
In this paper we derive some remarkable properties of McShane’s functional, defined by means of positive isotonic linear functionals. These properties are then applied to weighted generalized means. A series of consequences among additive and multiplicative type mean inequalities is given, as well as a special consideration of Hölder’s inequality, in view of the new results.  相似文献   
76.
In this paper, we prove that there exists an infinite series of finite simple groups of Lie type with connected prime graphs which are uniquely determined by their prime graphs. More precisely, we show that every finite group G with the same prime graph as ${{}^2D_{n}(3)}$ , where n ≥ 5 is odd, is necessarily isomorphic to the group ${{}^2D_{n}(3)}$ . In fact, we give a positive answer to an open problem that arose in Zavarnitsine (Algebra Logic 45(4):220–231, 2006). As a consequence of our result, we obtain that the simple group ${{}^2D_n(3)}$ , where n is an odd number, is characterizable by its spectrum.  相似文献   
77.
We present a numerical study of drag/lift and flux estimates using two forms of Navier‐Stokes equations (NSE) that are equivalent in the continuum formulation but not in the discrete finite element formulation. The two investigated forms of the NSE differ in the viscous term that is represented in one form by νΔ u with ν being the viscosity and 2ν?·?S u in the other form where ?S represents the deformation tensor. The study consists of numerical analysis of the two forms and computations of drag/lift, pressure drop on the cylinder problem and computations of flux for the Poiseuille flow. The main objective is to provide a clear comparison of the reference values for the maximal drag and lift coefficient at the cylinder and for the pressure difference between the front and the back of the cylinder at the final time for the two forms of NSEs. Our computational results of the reference values do not differ significantly between the two forms, but the differences are there. For the Poiseuille flow, the differences in the flux computations were much smaller, and this agreed with the computationally obtained results of the divergence of the velocity field. © 2011 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 28: 523–541, 2012  相似文献   
78.
The effect of Mn2+Co2+Ti4+ substitution on microwave absorption has been studied for BaCo0.5Mn0.5Ti1.0Fe10O19 ferrite-acrylic resin composites in frequency range from 12 to 20 GHz. X-ray diffraction (XRD), scanning electron microscope (SEM), vibrating sample magnetometer, AC susceptometer and vector network analyzer were used to analyze the structural, magnetic and microwave absorption properties. The results showed that the magnetoplumbite structures for all samples have been formed. Based on microwave measurement on reflectivity, BaCo0.5Mn0.5Ti1.0Fe10O19 may be a good candidate for electromagnetic compatibility and other practical applications at high frequency.  相似文献   
79.
80.
The one‐pot, three‐component, synthesis of a new series of 4‐hydroxy‐3‐(2‐arylimidazo[1,2‐a]pyridin‐3‐yl)quinolin‐2(1H)‐ones in the presence of DABCO as a catalyst has been achieved using aryl glyoxal monohydrates, quinoline‐2,4(1H,3H)‐dione, and 2‐aminopyridine in H2O/EtOH under reflux conditions. The cheapness of organocatalyst, simple workup, operational simplicity, regioselectivity, and high yields are some advantages of this protocol.  相似文献   
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