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11.
Yuli D. Chashechkin Vasiliy G. Baydulov Anatoliy V. Kistovich 《Journal of Engineering Mathematics》2006,55(1-4):313-338
Results of analytical studies of the governing equations of stratified rotating fluids based on the unification of theories
of continuous and discrete groups, perturbations and modern numerical visualizations are described. Symmetries of basic systems
and their simplified versions, different approximations and constitutive turbulent models are compared. A new method to calculate
discrete groups analytically, which does not need a preliminary search for continuous groups, is developed. As an example
of the practical use of the developed algorithm, a complete classification of cellular and roll structures of Bénard convection
is presented. A complete classification of 3D periodic motions in compressible viscous stratified and rotating fluids, including
regular (wave) and singular elements, is performed by perturbation methods. In all cases, in a viscous fluid, besides waves
there are two different periodic boundary layers. In a homogeneous fluid the split boundary layers are merged, thus forming
a joint doubly-degenerate structure. Stratification and rotation reduce the degeneration of the 3D periodic boundary layers.
Calculations of a 3D periodic wave beam emitted by an oscillating part of a sloping plane are visualized by a computer-graphics
method. The existence of thin extended components on the edges of the 3D wave cone is demonstrated. 相似文献
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13.
不可约模的张量积分解是李代数表示理论的重要问题,在计算最低双边胞腔上的Kazhdan-Lusztig多项式的首项系数时,有重要的应用.通过李代数中的相关知识和计算机编程,给出了A3型李代数的部分张量积分解的具体表达式,为进一步计算?3型仿射Weyl群最低双边胞腔上的Kazhdan-Lusztig首项系数奠定了基础. 相似文献
14.
Ana Triguero-Martínez Emilia Roy-Vallejo Nuria Montes Hortensia de la Fuente Ana María Ortiz Santos Castaeda Isidoro Gonzlez-lvaro Amalia Lamana 《International journal of molecular sciences》2022,23(13)
Galectin 1 (Gal1) exerts immunomodulatory effects leading to therapeutic effects in autoimmune animal models. Patients with rheumatoid arthritis have been reported to show higher Gal1 serum levels than the healthy population. Our study aimed to find genetic variants on the Gal1 gene (LGALS1) modulating its expression and/or clinical features in patients with early arthritis (EA). LGALS1 was sequenced in 53 EA patients to characterize all genetic variants. Then, we genotyped rs9622682, rs929039, and rs4820293, which covered the main genetic variation in LGALS1, in 532 EA patients. Gal1 and IL-6 serum levels were measured by ELISA and Gal1 also by western blot (WB) in lymphocytes from patients with specific genotypes. Once disease activity improved with treatment, patients with at least one copy of the minor allele in rs9622682 and rs929039 or those with GG genotype in rs4820293 showed significantly higher Gal1 serum levels (p < 0.05). These genotypic combinations were also associated with higher Gal1 expression in lymphocytes by WB and lower IL-6 serum levels in EA patients. In summary, our study suggests that genetic variants studied in LGALS1 can explain heterogeneity in Gal1 serum levels showing that patients with higher Gal1 levels have lower serum IL-6 levels. 相似文献
15.
深层稠油油藏超临界压力注汽开发技术研究 总被引:3,自引:1,他引:3
深层稠油油藏由于储层埋藏深、原油粘度高,油层有效吸汽所需的注汽压力往往高于常规注汽锅炉出口的额定压力,导致注气效果较差。为此,在对不同压力下饱和蒸汽焓、温度、潜热、比容以及超临界压力下蒸汽的比容、比焓等蒸汽热力学性质深入分析的基础上,对深层稠油油藏超临界压力注汽时的井筒热损失、储层受热半径进行了模拟计算,同时进一步预测了深层稠油超临界压力注汽开采效果。认为通过研制超临界压力锅炉、完善配套工艺、实施超临界压力注汽可以实现深层稠油乃至特、超稠油油藏的有效开发。 相似文献
16.
Dilatation of the aorta is a constantly evolving condition that can lead to the ultimate life-threatening event, acute aortic dissection. Recent research has tried to identify quantifiable biomarkers, with both diagnostic and prognostic roles in different aortopathies. Most studies have focused on the bicuspid aortic valve, the most frequent congenital heart disease (CHD), and majorly evolved around matrix metalloproteinases (MMPs). Other candidate biomarkers, such as asymmetric dimethylarginine, soluble receptor for advanced glycation end-products or transforming growth factor beta have also gained a lot of attention recently. Most of the aortic anomalies and dilatation-related studies have reported expression variation of tissular biomarkers. The ultimate goal remains, though, the identification of biomarkers among the serum plasma, with the upregulation of circulating MMP-1, MMP-2, MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1), asymmetric dimethylarginine (ADMA), soluble receptor for advanced glycation end-products (sRAGE) and transforming growth factor beta (TGF-β) being reported in association to several aortopathies and related complications in recent research. These molecules are apparently quantifiable from the early ages and have been linked to several CHDs and hereditary aortopathies. Pediatric data on the matter is still limited, and further studies are warranted to elucidate the role of plasmatic biomarkers in the long term follow-up of potentially evolving congenital aortopathies. 相似文献
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High Broad‐Band Photoresponsivity of Mechanically Formed InSe–Graphene van der Waals Heterostructures 下载免费PDF全文
19.
从工程实际实施的角度出发,对国内外现有耐压试验标准进行了对比分析,综合考虑检测效果、理论研究成果、试验设备能力、工程实际情况和社会经济效益等多方面因素,提出了采用混联方式实现长距离500 k V电缆线路工程变频耐压试验的检测方法,同时,提出了变频谐振耐压过程中同步开展分布式局部放电检测的方法,可满足500 k V长距离交联电缆线路耐压过程中的局部放电分布式同步检测。在北京海淀500 k V电缆工程中,实施完成了世界上首次1.7 U_0/60 min条件下500 k V长距离交联电缆线路变频谐振耐压与分布式局部放电同步检测的现场试验应用,有效地支撑了海淀500 k V电缆线路的交接试验。 相似文献
20.
Chemical Composition and Physical Properties of High Oleic Safflower Oils (Carthamus tinctorius,Var. CW88-OL and CW99-OL) 下载免费PDF全文
Florencia Salaberría Diana Constenla Amalia A. Carelli María E. Carrín 《Journal of the American Oil Chemists' Society》2016,93(10):1383-1391
Chemical composition and physical properties of CW88‐OL and CW99‐OL cultivars of high oleic safflower seeds and their hexane‐extracted oils were determined. Dry‐based seed composition of CW88‐OL and CW99‐OL was: moisture = 4.29 and 4.23 %, oil = 42.29 and 46.44 %, Crude protein = 20.94 and 16.41 %, neutral detergent fiber = 28.11 and 28.49 %, ash = 1.55 and 2.01 %, phosphorus content = 2033 and 3995 mg/kg, respectively. Major fatty acids in oils were ~78 % oleic (O), ~13 % linoleic (L), ~5 % palmitic (P) and ~2 % stearic (St) acids, for both cultivars. The main triacylglycerols were OOO (~50 %), OOL (~20 %), SOL + OPO (~10 %), and LLP (~5 %). The oil composition of CW88‐OL and CW99‐OL in main minor components was: α‐tocopherol = 582 and 551 mg/kg, total sterols = 3996 and 3362 mg/kg, phospholipids = 22 and 21 mg/kg and wax content = 70 and 74 mg/kg. For both cultivars, density and viscosity of the oils between 25 and 55 °C varied from 903.4 to 912.6 kg/m3 and 63 to 23 mPa.s showing linear and exponential behaviors, respectively. The refractive index was 1.4694. The CIELab color parameters were: 89.69 and 89.53 (L*), ?3.72 and ?3.07 (a*), and 47.28 and 47.78 (b*) (CW88‐OL and CW99‐OL, respectively). Thus, the high oil content of the seeds and nutritional quality of the oil accompanied by low levels of waxes and phospholipids makes the cultivars studied promising for producers and consumers. 相似文献