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The aim of this research is to conduct an experiment that will evaluate the effect of combining of counter flow air-impinging arrangement and an arc-shaped turbulators over the absorber plate of solar heater. This combination is intended to improve the thermohydraulic performance of the solar air heater. The parameters such as energy transfer and frictional factor are studied at flow Reynolds number varies from 18,000 to 3600, and the influence of a hole jet bore ratio from 0.0430 to 0.109 is considered. At the optimal hole jet bore ratio of 0.0650, the thermo-hydraulic achievement parameter has a value of 1.75, which is the greatest possible value can be attained. When compared to multi-pass V and multiple V roughened solar air heaters based on the THAP, the current work is improved the performance by 55.3 and 32.9%, respectively. Such comparisons clearly demonstrate the superiority of the present work. Furthermore, a relationship is shown between the jet hole bore ratio and the thermohydraulic performance measure, with a maximum divergence of 10%. [ABSTRACT FROM AUTHOR]

Presently, waste management is the primary focus of scientific inquiry. The recyclable and reusable organic waste are dumbed a lot as landfills in the environment and that could be converted into application-oriented polymer reinforcing material. Cellulose is a widespread biopolymer that is found in the majority of bio waste materials. The organic waste Citrus x sinensis peel (Citrus × aurantium f. aurantium) is used as a raw material in this research. The waste material was utilized to extract the cellulose using optimum chemical conditions such as alkali treatment, acid hydrolysis, and bleaching and purification process. Fourier transform spectroscopy was applied to the cellulose to detect the functional groups it contained and indicated progressive removal of non-cellulosic constituents. The cellulose that was extracted has a yield percentage of 67.82% and a density of 1.413 g/cm3. The differential scanning curve analysis reveals that the temperature of degradation is 308.17 °C. Through the utilisation of thermogravimetric analysis, each phase of thermal activity was studied. According to an X-ray diffraction investigation, cellulose has a crystalline size of 9.63 nm and a higher crystallinity index of 72.54 percent exhibiting unique physicochemical properties. The Scanning electron microscopy shows the different size and shape of particles oriented with rough surface. Using ImageJ software, the other distinguishing characteristics of surface morphology, and particle size analysis are performed. The elemental analysis demonstrates the cellulose's organic nature by demonstrating its higher carbon and oxygen content. On the basis of the physicochemical characteristics of the celluloses, it could be considered as alternative sources of cellulose for potential value-added industrial applications and more applicable for the polymer composite reinforcement filler material. [ABSTRACT FROM AUTHOR]

The near-dry electrical discharge machining processes have been conducted using air-mist or gas mist as a dielectric fluid to minimize the environmental impacts. In this article, near-dry electrical discharge machining (NDEDM) experiments have been performed to improve machining performance using an oxygen-mist dielectric fluid, a copper composite electrode, and Cu-Al-Be polycrystalline shape memory alloy (SMA) work materials. The copper composite electrode is made up of 12 wt% silicon carbide and 9 wt% graphite particles. The oxygen-mist pressure (Op), pulse on time (Ton), spark current (Ip), gap voltage (Gv), and flow rate of mixed water (Fr) were used as process parameters, and the material removal rate (MRR), tool wear rate (TWR), and surface roughness (SR) were used as performance characteristics. The global optimal alternative solution has been predicted by the PROMETHEE-II (Preference Ranking Organization METhod for Enrichment Evaluations-II) optimization technique. The best combinations of process parameters have been used to examine the microstructure of composite tools and SMA-machined surfaces by scanning electron microscopy (SEM) analysis. The best global optimum settings (oP: 9 bar, Ip: 60 µs, Ip: 12 A, Gv: 40 V, and Fr: 12 ml/min) are predicted to attain optimum machining performance (MRR: 39.049 g/min, TWR: 1.586 g/min, and SR: 1.78 µm). The tool wear rate of the NDEDM process has been significantly reduced by the copper composite electrode due to increasing microhardness, wear resistance, and melting point. When compared to the pure copper electrode tool, the MRR of NDEDM is improved to 21.91%, while the TWR and SR are reduced to 46.66% and 35.02%, respectively. [ABSTRACT FROM AUTHOR]

β-lactamases inactivate β-lactam antibiotics leading to drug resistance. Consequently, inhibitors of β-lactamases can combat this resistance, and the β-lactamase inhibitory protein (BLIP) is a naturally occurring inhibitor. The widespread CTX-M-14 and CTX-M-15 β-lactamases have an 83% sequence identity. In this study, we show that BLIP weakly inhibits CTX-M-14 but potently inhibits CTX-M-15. The structure of the BLIP/CTX-M-15 complex reveals that binding is associated with a conformational change of an active site loop of β-lactamase. Surprisingly, the loop structure in the complex is similar to that in a drug-resistant variant (N106S) of CTX-M-14. We hypothesized that the pre-established favorable loop conformation of the N106S mutant would facilitate binding. The N106S substitution results in a ~100- and 10-fold increase in BLIP inhibition potency for CTX-M-14 and CTX-M-15, respectively. Thus, this indicates that an active site loop in β-lactamase toggles between conformations that control antibiotic hydrolysis and inhibitor susceptibility. These findings highlight the role of accessible active site conformations in controlling enzyme activity and inhibitor susceptibility as well as the influence of mutations in selectively stabilizing discrete conformations. β-lactamases are a source of antibiotic resistance. Here, the authors show that an active site loop in β-lactamase toggles between conformations that control antibiotic hydrolysis and inhibitor susceptibility, highlighting the role of active site conformations in enzyme activity and inhibition. [ABSTRACT FROM AUTHOR]

Reverse logistics has emerged as an important dimension for organizations to build their strategic advantage. Part of this effort relies on potentially outsourcing these activities. With this competitive issue in mind, this paper presents a multistep process to select a third-party reverse logistic provider (3PRLP). Criteria for evaluation are drawn from the literature and practical input from experts and decision makers within a case company. The process requires that an initial screening of criteria is completed through the analytical hierarchy process. The second stage of the process, 3PRLP selection, is completed using the analytic network process. An illustrative example is provided to demonstrate the solutions obtained by the proposed process within an automobile case company. A sensitivity analysis is also provided for a robustness check. The results obtained from the proposed model provide some interesting managerial implications to the case company and others wishing to apply the process. [ABSTRACT FROM AUTHOR]