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41.
Research on Chemical Intermediates - A series of new complexes derived from Pd(II), Cu(II) and Fe(III) ions reacted with thiazole derivative (HL, CPTP) was prepared. Structures of all new compounds...  相似文献   
42.
Journal of Thermal Analysis and Calorimetry - The present paper concerns the bioconvective flow, mass and heat transfer including motile microorganisms on a vertical surface saturated with porous...  相似文献   
43.
Research on Chemical Intermediates - This paper attempts to explore the synergism of hybrid advanced oxidation processes, which are sono-photo-catalysis and sono-photo-activated two oxidation...  相似文献   
44.
Alzahrani E  Welham K 《The Analyst》2011,136(20):4321-4327
Sample pretreatment is a required step in proteomics in order to remove interferences and preconcentrate the samples. Much research in recent years has focused on porous monolithic materials since they are highly permeable to liquid flow and show high mass transport compared with more common packed beds. These features are due to the micro-structure within the monolithic silica column which contains both macropores that reduce the back pressure, and mesopores that give good interaction with analytes. The aim of this work was to fabricate a continuous porous silica monolithic rod inside a heat shrinkable tube and to compare this with the same material whose surface has been modified with a C(18) phase, in order to use them for preconcentration/extraction of proteins. The performance of the silica-based monolithic rod was evaluated using eight proteins; insulin, cytochrome C, lysozyme, myoglobin, β-lactoglobulin, ovalbumin, hemoglobin, and bovine serum albumin at a concentration of 60 μM. The results show that recovery of the proteins was achieved by both columns with variable yields; however, the C(18) modified silica monolith gave higher recoveries (92.7 to 109.7%) than the non-modified silica monolith (25.5 to 97.9%). Both silica monoliths can be used with very low back pressure indicating a promising approach for future fabrication of the silica monolith inside a microfluidic device for the extraction of proteins from biological media.  相似文献   
45.
We study the dynamical boundary value problem for Hamilton‐Jacobi equations of the eikonal type with a small parameter. We establish two results concerning the asymptotic behavior of solutions of the Hamilton‐Jacobi equations: one concerns with the convergence of solutions as the parameter goes to zero and the other with the large‐time asymptotics of solutions of the limit equation.  相似文献   
46.
NH3 synthesis by the Haber–Bosch method is regarded as the dominant method in industry. Such a process is energy‐intensive, accompanied by a large amount of CO2 emission. Electrocatalytic N2 reduction is a sustainable avenue for NH3 production at ambient conditions. However, it needs a catalyst to boost the N2 reduction reaction. Here, we demonstrate that DyF3 is an efficient electrocatalyst. In 0.1 m Na2SO4, DyF3 attains a large NH3 yield of 10.9 μg h?1 mg?1cat. at ?0.45 V vs. the reversible hydrogen electrode, with the corresponding Faradaic efficiency of 8.8 %. Furthermore, this catalyst exhibits high electrochemical stability.  相似文献   
47.
The generalized model for plasma, thermal, and elastic waves under dual phase lag model have been applied to determine the carrier density, the displacement, the temperature, and the stresses in a semiconductor medium. Using Laplace transform and the eigenvalue approach methodology, the solutions of all variables have been obtained analytically. A semiconducting material like as silicon was considered. The results were graphically represented to show the different between the dual phase model, Lord and Shulman’s theory and the classical dynamical coupled theory.  相似文献   
48.
This article deals with Darcy–Forchheimer three dimensional (3D) flow of water-based carbon nanotubes (CNTs) with heterogeneous–homogeneous reactions. A bidirectional nonlinear extendable surface has been employed to create the flow. Flow in porous space is represented by Darcy–Forchheimer expression. Heat transfer mechanism is explored through convective heating. Equal diffusion coefficients are considered for both auto catalyst and reactants. Results for single-wall (SWCNT) and multi-wall (MWCNT) carbon nanotubes have been presented and compared. The diminishment of partial differential framework into nonlinear ordinary differential framework is made through suitable transformations. Optimal homotopy scheme is used for arrangements development of governing flow problem. Optimal homotopic solution expressions for velocities and temperature are studied through plots by considering various estimations of physical variables. Moreover the surface drag coefficients and heat transfer rate are analyzed through plots.  相似文献   
49.

The increasing demand for sustainable energy has diverted researchers’ intentions toward electrochemical storage devices. This research aims to combine supercapacitors’ characteristics with batteries to create high-performance hybrid energy storage devices. The hydrothermal approach is used to synthesize silver sulfide (Ag2S), strontium sulfide (SrS), and their composite silver strontium sulfide (AgSrS). XRD is used to evaluate the crystallinity, SEM is used to study the surface morphology, and XPS is used to determine the elemental composition of AgSrS. The BET measurements show a higher surface area of 22.23 m2g−1 for AgSrS. The highest achieved specific capacity with AgSrS is 494.5 C g−1 (137.36 mAh-g−1). The best-tuned material, AgSrS, is then used as the anode in a powered hybrid device with activated carbon (A.C.) as the cathode terminal. This device provides an energy of 26.32 Wh-kg−1 at a power of 800 W kg−1. The device was also put through a durability test, which included 5000 consecutive cycles. After 5000 cycles, a columbic efficiency of 82% was achieved, with 96% capacity retention. This research shows that the composite material AgSrS can be utilized commercially for hybrid energy storage devices in the future.

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50.
Metal negatrode supercapattery (MNSC) is an emerging technology that combines the high energy storage capabilities of batteries with the high-power delivery of supercapacitors, thereby offering promising solutions for various applications, such as energy storage systems, electric vehicles, and portable electronics. This review article presents a comprehensive analysis of the potential of MNSCs as a prospective energy storage technology. MNSCs utilize a specific configuration in which the negatrode consists of a metal or metal-rich electrode, such as sodium, aluminum, potassium, or zinc, whereas the positrode functions as a supercapacitor electrode. The utilization of negatrodes with low electrochemical potential and high electrical conductivity is crucial for achieving high specific energy in energy storage devices, despite facing numerous challenges. The present study discusses the design and fabrication aspects of MNSCs, including the selection of appropriate metal negatrodes, electrolytes, and positrodes, alongside the fundamental operational mechanisms. Additionally, this review explores the challenges encountered in MNSCs and proposes solutions to enhance their performance, such as addressing dendrite formation and instability of metal electrodes.  相似文献   
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