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91.
Clean Technologies and Environmental Policy - There is a dire need to replace the chemical buffers that regulate the redox environment in single-stage anaerobic digestion of food waste. Hence, the...  相似文献   
92.
Multimedia Tools and Applications - Both Visual Question Answering (VQA) and image captioning are the problems which involve Computer Vision (CV) and Natural Language Processing (NLP) domains. In...  相似文献   
93.
The heat and mass transfer of unsteady magnetohydrodynamic (MHD) flow of Newtonian fluid with Hall current and ion-slip currents due to vast possible engineering applications is very important in areas like power generators, MHD accelerators, refrigeration coils, electric transformers, and heating elements. A quality-based research on Hall and ion-slip consequences on the rotating unsteady MHD flow past an infinite perpendicular moving absorbent plate have not been performed. Therefore, the Hall and ion-slip consequences on rotating unsteady MHD flow past an infinite perpendicular moving absorbent plate have not been performed. The similarity transformations are engaged to transfer the governing partial differential equations within favor of the scheme of nonlinear ordinary differential equations and elucidated numerically making use of cubic B-splines collocation mechanism. The influences of felicitous parameters on basic equations are remarked on through graphical profiles. Even though the computational estimations of frictional forces, Nusselt number, and Sherwood number for various parameters are distributed in tabular format and exchanged of views comparatively.  相似文献   
94.
Neural Computing and Applications - The identification of water stress is a major challenge for timely and effective irrigation to ensure global food security and sustainable agriculture. Several...  相似文献   
95.
Journal of Porous Materials - In order to facilitate the large-scale applications of rechargeable Zn–air batteries, non-noble-metal based materials with high activity for oxygen reduction...  相似文献   
96.
Phosphodiesterases (PDEs) hydrolyze cyclic nucleotides to modulate multiple signaling events in cells. PDEs are recognized to actively associate with cyclic nucleotide receptors (protein kinases, PKs) in larger macromolecular assemblies referred to as signalosomes. Complexation of PDEs with PKs generates an expanded active site that enhances PDE activity. This facilitates signalosome-associated PDEs to preferentially catalyze active hydrolysis of cyclic nucleotides bound to PKs and aid in signal termination. PDEs are important drug targets, and current strategies for inhibitor discovery are based entirely on targeting conserved PDE catalytic domains. This often results in inhibitors with cross-reactivity amongst closely related PDEs and attendant unwanted side effects. Here, our approach targeted PDE–PK complexes as they would occur in signalosomes, thereby offering greater specificity. Our developed fluorescence polarization assay was adapted to identify inhibitors that block cyclic nucleotide pockets in PDE–PK complexes in one mode and disrupt protein-protein interactions between PDEs and PKs in a second mode. We tested this approach with three different systems—cAMP-specific PDE8–PKAR, cGMP-specific PDE5–PKG, and dual-specificity RegA–RD complexes—and ranked inhibitors according to their inhibition potency. Targeting PDE–PK complexes offers biochemical tools for describing the exquisite specificity of cyclic nucleotide signaling networks in cells.  相似文献   
97.
The synthesis, subsequent flash sintering (FS) characteristics and microstructures of pure and Li-incorporated ZnO powders are reported. At low concentrations, Li is a substitutional occupant in ZnO but becomes an amphoteric dopant (substitutional and interstitial occupant) at higher concentrations inferred from a contraction reversal of the unit cell volume. Increasing Li reduces the average flash temperature of ZnO modestly by 15°C, and a doubling of the linear shrinkage. A discernible color smear (yellow–white–dark) stretching from the anode to cathode imputable to strong electromigration is also observed. Microanalyses of the electrode regions establish clear evidence of electrochemical (EC) lithiation into ZnO and the formation of Li–Zn compounds not observed in conventional sintering (CS). Interestingly, in contrast to CS, the addition of Li enhances coarsening during FS, suggestive of a dissolution–reprecipitation process concurrent with the EC lithiation process. Evidence for considerable (local) yet tangible temperature, chemical and microstructural asymmetry among electrodes driven by EC reactions is presented. Probable mechanisms, leading to these observations, are discussed.  相似文献   
98.
Clay bricks are one of the most widely used materials in building construction due to their advantages, including local availability, ease of fabrication and cost-effectiveness. Fire is one of the dangerous hazards that can cause damage the life and property. Lightweight plasters play a vital role in insulating the masonry construction during fire accident. There is only limited data and information available on the fire performance of Clay Brick Masonry (CBM) insulated with lightweight plaster. An extensive investigation was undertaken to evaluate the residual strength properties and physical characteristics of CBM prisms exposed to elevated temperatures. CBM prisms plastered with M-sand mortar, vermiculite mortar, and perlite mortar were used for the investigation. Protected prisms were exposed to elevated temperatures following the ISO 834 standard fire curve for durations of 30 min (821°C), 60 min (925°C), 90 min (986°C), and 120 min (1029°C). Mechanical properties such as axial load carrying capacity, stress–strain behaviour, elastic modulus, and crack pattern were examined. The mechanical properties of CBM prisms were found to be highly influenced by the type of plastering, intensity, and the duration of heating. The microstructure and image analysis confirmed the effects of temperature exposure on protective plasters. Equations are proposed to determine the residual axial compressive strength and the elastic modulus of CBM. It was found that the specimens plastered with perlite mortar had better fire resistance.  相似文献   
99.
Lipids are key constituents of numerous biomedical drug delivery technologies. Here, we present the design, synthesis and biophysical characterizations of a library of cationic lipids containing an acetal residue in their linker region. These cationic acetal lipids (CALs) were conveniently prepared through a trans-acetalization protocol from commercially available precursors. NMR studies highlighted the conformational rigidity at the acetal residue and the high hydrolytic stability of these CALs. Fluorescence anisotropy studies revealed that the CAL with a pyridinium headgroup (CAL1) formed highly cohesive vesicular aggregates in water. These structural and self-assembly features of the CAL1 allowed up to 196 % w/w loading of curcumin (Cur) as a representative hydrophobic drug. A reconstitutable formulation of Cur was obtained as a result, which could deliver the drug inside mammalian cells with very high efficiency. The hemocompatibility and cytocompatibility of CAL1 was significantly enhanced by creating a coating of polydopamine (PDA) onto its vesicular assemblies to produce hybrid lipid-polymer nanocapsules. This work demonstrates rapid access to the useful synthetic lipid formulations with high potential in drug and gene delivery applications.  相似文献   
100.
Synthetic surfaces engineered to regulate phase transitions of matter and exercise control over its undesired accrual (liquid or solid) play a pivotal role in diverse industrial applications. Over the years, the design of repellant surfaces has transitioned from solely modifying the surface texture and chemistry to identifying novel material systems. In this study, selection criteria are established to identify bio-friendly phase change materials (PCMs) from an extensive library of vegetable-based/organic/essential oils that can thermally respond by harnessing the latent heat released during condensation and thereby delaying ice/frost formation in the very frigid ambient that is detrimental to its functionality. Concurrently, a comprehensive investigation is conducted to elucidate the relation between microscale heat transport phenomena during condensation and the resulting macroscopic effects (e.g., delayed droplet freezing) on various solidified PCMs as a function of their inherent thermo-mechanical properties. In addition, to freeze protection, many properties that are responsive to the thermal reflex of the surface, such as the ability to dynamically tune optical transparency, moisture harvesting, ice shedding, and quick in-field repairability, are achievable, resulting in the development of protective coatings capable of spanning a wide range of functionalities and thereby having a distinctive edge over conventional solutions.  相似文献   
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