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21.
When two circular jets impinge upon each other along the axis of a hemi-spherical shell then a free jet on a hemi-spherical shell is formed. The governing equations are Prandtl’s momentum boundary layer equation and the continuity equation. The conserved quantity is required for the free jet on a hemi-spherical shell. The conserved quantity for the free jet on a hemi-spherical shell is established with the help of a conserved vector. The group invariant solution for the third-order partial differential equation for the stream function is constructed.  相似文献   
22.
In this paper, the concepts and the formalism associated with monomiality principle and Sheffer sequences are used to introduce family of Hermite-based Sheffer polynomials. Some properties of Hermite-Sheffer polynomials are considered. Further, an operational formalism providing a correspondence between Sheffer and Hermite-Sheffer polynomials is developed. Furthermore, this correspondence is used to derive several new identities and results for members of Hermite-Sheffer family.  相似文献   
23.
The mechanical properties of miscible poly(butylene terephthalate) (PBT)/poly (hydroxy ether of bisphenol A) (phenoxy) blends obtained by melt mixing have been studied by means of the tensile test. The crystallinity of the blends has been studied by means of DSC and density measurements. A synergistic behavior, principally in the break properties, at high PBT contents in the blends is observed. As can be seen from the torque and density data, this synergistic behavior is related with the high level of miscibility which seems to exist at high PBT contents compared with that of the high phenoxy content region.  相似文献   
24.
The conservation laws for laminar axisymmetric jet flows with weak swirl are studied here. The multiplier approach is used to derive the conservation laws for the system of three boundary layer equations for the velocity components governing flow in laminar axisymmetric jet flows with weak swirl. Conservation laws for the system of two partial differential equations for the stream function are also derived.  相似文献   
25.
A series of novel thiazine derivatives featuring axial chirality in both (R) and (S) configurations were successfully synthesized by N-heterocyclic carbene (NHC)-catalyzed enantioselective [3 + 3] annulations, and their potential as anti-plant virus agents against potato virus Y (PVY) was evaluated. Biological activity results demonstrated that most of these chiral thiazine derivatives exhibited significant activities against PVY. Notably, compound (S) -3g displayed a remarkable 58% inactivation effect against PVY at a concentration of 500 μg/mL, slightly surpassing the effectiveness of Ningnanmycin (NNM) at 57%. Additionally, (S) -3g exhibited curative activity of 57%, which is superior to NNM (53%). Molecular docking studies revealed preliminary insights into the distinct biological properties of the two different enantiomers, (R) or (S) -3g against PVY, wherein single enantiomer (S) -3g formed a more stable interaction with PVY-CP, as indicated by its lower binding free energy (−41.18 kcal/mol) compared to (R)- 3g (−36.9 kcal/mol). The findings in this study with a new class of axially chiral thiazine derivatives shall inspire further development of chiral heterocycles as potential drug candidates for the protection of plant virus infections.  相似文献   
26.
Microalgae have been proposed as a promising source for biodiesel production. Focusing on algal strains for biodiesel production, efforts should be made to search new strains. Experiments were carried out to investigate the effects of growth parameters (nutrients, pH, light, aeration and temperature) and the oil percentage of eight algal strains (Chlorella sp., Cladophora sp., Hydrodictylium sp., Oedogonium sp., Oscillatoria sp., Spirogyra sp., Stigeocolonium sp., Ulothrix sp.). Results show that 6.5–7.5 is the optimum pH for the growth of all algal species. Temperature showed a greater variation (25°40°C). Ulothrix sp. gave more biomass productivity and is the most suitable strain for biodiesel production due to higher oil percentage (62%). Least biomass production was observed for Stigeocolonium sp. and least oil content was obtained from Hydrodictylium sp. It was observed that among these eight algal strains for biodiesel production, Ulothrix and Chlorella are the most promising algae species.  相似文献   
27.
28.
The current study assessed the spatiotemporal variations and human health surveillance associated with organochlorine pesticide (OCP) contamination in water, sediments, and fish from Chenab River, Pakistan. The OCP determinations were performed using high-performance liquid chromatography with a reverse-phase C18 column. The total OCP levels ranged from 13.33 to 274.59?ng/L in water, 4.63 to 239.11?ng/g in sediments, and 23.79 to 387.12?ng/g in fish species. The overall pattern of mean OCP concentrations followed the order as ΣDDTs?>?Σendosulfan?>?aldrin and OCP pollution pattern among the headworks were Khanki Barrage?>?Qadirabad Barrage?>?Trimmu Barrage?>?Marala Barrage in all three environmental matrixes during both seasons. The estimated daily intake (EDI) for ∑OCPs was found to be 22.44?ng/kg/day. The hazard ratios calculated to assess the carcinogenic risk indicated that the values for ∑DDT and aldrin at the 95th percentile concentrations were greater than one, indicating the probability of carcinogenic risk occurrence of one in million populations due to fish consumption. Therefore, these high levels of OCPs and carcinogenic risk through fish consumption highlight the needs of immediate elimination of OCPs from riverine environment of Chenab River and we recommend long-term monitoring-based freshwater ecological studies to be conducted in the study area.  相似文献   
29.
A family of coordination complexes has been synthesized, each comprising a ruthenium(II) center ligated by a thiacrown macrocycle, [9]aneS(3), [12]aneS(4), or [14]aneS(4), and a pair of cis-coordinated ligands, niotinamide (nic), isonicotinamide (isonic), or p-cyanobenzamide (cbza), that provide the complexes with peripherally situated amide groups capable of hydrogen bond formation. The complexes [Ru([9]aneS(3))(nic)(2)Cl]PF(6), 1(PF(6)); [Ru([9]aneS(3)) (isonic)(2)Cl]PF(6), 2(PF(6)); [Ru([12]aneS(4))(nic)(2)](PF(6))(2), 3(PF(6))(2); [Ru([12]aneS(4))(isonic)(2)](PF(6))(2), 4(PF(6))(2); [Ru([12]aneS(4)) (cbza)(2)](PF(6))(2), 5(PF(6))(2); [Ru([14]aneS(4))(nic)(2)](PF(6))(2), 6(PF(6))(2); [Ru([14]aneS(4))(isonic)(2)](PF(6))(2), 7(PF(6))(2); and [Ru([14]aneS(4))(cbza)(2)](PF(6))(2), 8(PF(6))(2) have been characterized by NMR spectroscopy, mass spectrometry, and elemental analysis. UV/visible spectroscopy shows that each complex exhibits an intense high-energy band (230-255 nm) assigned to a pi-pi* transition and a lower energy band (297-355 nm) assigned to metal-to-ligand charge-transfer transitions. Electrochemical studies indicate good reversibility for the oxidations of complexes with nic and isonic ligands (|I(a)/I(c)| = 1; DeltaEp < 100 mV), In contrast, complexes 5 and 8, which incorporate cbza ligands, display oxidations that are not fully electrochemically reversible (|I(a)/I(c)| = 1, DeltaEp > or = 100 mV). Metal-based oxidation couples between 1.32 and 1.93 V versus Ag/AgCl can be rationalized in term of the acceptor capabilities of the thiacrown ligands and the amide-bearing ligands, as well as the pi-donor capacity of the chloride ligands in compounds 1 and 2. The potential to use these electroactive metal complexes as building blocks for hydrogen-bonded crystalline materials has been explored. Crystal structures of compounds 1(PF(6)).H(2)O, 1(BF(4)).2H(2)O, 2(PF(6)), 3(PF(6))(2), 6(PF(6))(2)CH(3)NO(2), and 8(PF(6))(2) are reported. Four of the six form amide-amide N-H...O hydrogen bonds leading to networks constructed from amide C(4) chains or tapes containing R(2)(2) (8) hydrogen-bonded rings. The other two, 2(PF(6)) and 8(PF(6)), form networks linked through amide-anion N-H...F hydrogen bonds. The role of counterions and solvent in interrupting or augmenting direct amide-amide network propagation is explored, and the systematic relationship between the hydrogen-bonded networks formed across the series of structures is presented, showing the relationship between chain and tape arrangements and the progression from 1D to 2D networks. The scope for future systematic development of electroactive tectons into network materials is discussed.  相似文献   
30.
The effect of nonlinear mixed convection in stretched flows of rate-type non-Newtonian materials is described. The formulation is based upon the Maxwell liquid which elaborates thermal relation time characteristics. Nanofluid properties are studied considering thermophoresis and Brownian movement. Thermal radiation, double stratification, convective conditions, and heat generation are incorporated in energy and nanoparticle concentration expressions. A boundary-layer concept is implemented for the simplification of mathematical expressions. The modeled nonlinear problems are computed with an optimal homotopy scheme. Moreover, the Nusselt and Sherwood numbers as well as the velocity, nanoparticle concentration, and temperature are emphasized. The results show opposite impacts of the Deborah number and the porosity factor on the velocity distribution.  相似文献   
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