Composite power law holdup correlations in horizontal pipes

A wide range of experimental holdup data, from different sources, are analyzed based on a theoretical model proposed in this work to evaluate the holdup in horizontal pipes. 2276 gas–liquid flow experiments in horizontal pipelines with a wide range of operational conditions and fluid properties are included in the database. The experiments are classified by mixture Reynolds number ranges and composite analytical expressions for the relationship between the liquid holdup and no-slip liquid holdup vs. the gas–liquid volumetric flow rate are obtained by fitting the data with logistic dose curves. The Reynolds number appropriate to classify the experimental data for gas–liquid flows in horizontal pipes is based on the mixture velocity and the liquid kinematic viscosity. Composite power law holdup correlations for flows sorted by flow pattern are also obtained. Error estimates for the predicted vs. measured holdup correlations together with standard deviation for each correlation are presented. The accuracy of the correlations developed in this study is compared with the accuracy of 26 previous correlations and models in the literature. Our correlations predict the liquid holdup in horizontal pipes with much greater accuracy than those presented by previous authors.     

Development of two-step radioimmunoassay (RIA) for the measurement of free triiodothyronine in human serum based on antibody coated tubes

Journal of Radioanalytical and Nuclear Chemistry - We describe a simple, user friendly two-step radioimmunoassay (RIA) based on antibody coated tubes for the measurement of free triiodothyronine in...     

Fe2P2O7(H2O)2

The compound diiron diphosphate dihydrate, Fe₂P₂O₇(H₂O)₂, was synthesized hydro­thermally and crystallizes in the monoclinic space group P2₁/n. The compound has a somewhat open framework made up of edge‐sharing iron(II) octahedra that form chains connected by five bridging diphosphates. The remaining octahedral site of each iron is occupied by coordinated water. The H atoms of the water molecules all point into a common channel.     

Gastroesophageal reflux laryngitis resistant to omeprazole therapy

Gastroesophageal reflux disease (GERD) is known to cause a variety of symptoms that lead a patient to seek otolaryngologic care. New advances in the treatment of GERD have enabled otolaryngologists to eliminate most of the signs and symptoms caused by acid reflux. Omeprazole, the most recent pharmacologic advancement, has been reported to be universally successful in controlling acid release from the stomach of patients with GERD. This report describes a series of patients with GERD for whom high-dose omeprazole therapy was not successful in completely reducing gastric acid levels of GERD symptomatology.     

松质骨拉伸细观分析的实验研究

设计了扫描电镜内专用的加载装置,研究了松质骨受拉时胞体结构的细观力学行为,获得了不同加载条件下的松质骨SEM照片和断口SEM照片,为分析松质骨变形机理和破坏机理提供实验基础,也为同类研究提供有益参考。     

Synthesis,characterization and antimicrobial activities of copper complexes derived from 4-aminoantipyrine derivatives

Cu(II) complexes have been synthesized from the Schiff base ligands derived from furfurlyidene-4-aminoantipyrine and aniline (L¹)/p-nitroaniline (L²)/p-hydroxyaniline (L³). They were characterized using analytical and spectral techniques. All the Cu(II) complexes exhibit square planar geometry. The X-band ESR spectra of the copper complexes in DMSO solution at 300 and 77 K were recorded and their salient features are reported. The in vitro biological screening effects of the investigated compounds were tested against the bacterial species, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris and Pseudomonas aeruginosa and fungal species, Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola and Candida albicans by serial dilution method. A comparative study of inhibition values of the Schiff base ligands and their complexes indicate that the complexes exhibit higher antimicrobial activity than the Schiff base ligands. Superoxide dismutase and reducing power activities of the copper complexes have also been studied. Depending on the molecular structure, the [CuL²(OAc)₂] complex possess promising SOD mimetic activities.     

具有半边裂纹导电薄板放电瞬间的温度场数值模拟

采用数值模拟方法 ,模拟计算了具有半边裂纹的导电薄板在放电瞬间的温度场分布。计算结果表明 :在裂纹尖端附近由于电磁热的集中效应 ,可使材料熔化形成焊口 ,裂纹尖端处的曲率半径显著增大 ,并且焊口的温度分布与形状是不完全对称的。裂纹尖端焊口形状的模拟计算结果与试验结果非常吻合。从温度梯度的分布结果可知 ,裂纹前缘附近在放电过程中将产生很大的压应力 ,可显著减少甚至是消除裂纹前缘处的扩展应力数值 ,抑制了裂纹主干线的形成 ,可达到遏制裂纹扩展的目的     

Characterization and optimization of a positively charged poly (ethylene glycol)diacrylate hydrogel as an actuating muscle tissue engineering scaffold

Hydrogels have been used for many applications in tissue engineering and regenerative medicine due to their versatile material properties and similarities to the native extracellular matrix. Poly (ethylene glycol) diacrylate (PEGDA) is an ionic electroactive polymer (EAP), a material that responds to an electric field with a change in size or shape while in an ionic solution, that may be used in the development of hydrogels. In this study, we have investigated a positively charged EAP that can bend without the need of external ions. PEGDA was modified with the positively charged molecule 2‐(methacryloyloxy)ethyl‐trimethylammonium chloride (MAETAC) to provide its own positive ions. This hydrogel was then characterized and optimized for bending and cellular biocompatibility with C2C12 mouse myoblast cells. Studies show that the polymer responds to an electric field and supports C2C12 viability.     

The Hilbert-Chow morphism and the incidence divisor: Zero-cycles and divisors

For a smooth projective variety X of dimension n, on the product of Chow varieties C_a(X)×C_n−a−1(X) parameterizing pairs (A,B) of an a-cycle A and an (n−a−1)-cycle B in X, Barry Mazur raised the problem of constructing a Cartier divisor supported on the locus of pairs with A∩B≠0?. We introduce a new approach to this problem, and new techniques supporting this approach.