Determining the optimal procurement policy and maximum allowable lifespan for machining tools with stochastically distributed toollife

For high-value added products, machining tools’ lifespan significantly influences the quantity of procurement in machining process. Preemption of tools from the workpiece while processing is continuing is sometime beneficial to safeguard the product from the damage due to tool failure or its malfunction. Also an early discard of a tool is costly for the manufacturing operation. Therefore an optimal strategy for the tool life is sought here to determine the maximum allowable tool lifespan to preempt from the workpiece and to have an appropriate amount of tool stock in the crib to ascertain the proper running of the production schedule and tool inventory. Therefore, an impact of the machining tool lifespan on the production-inventory policy of the system is investigated in this paper. An integrated lifespan related inventory model for machining tools is developed to meet the responding accurate requirement of procurement and inventory. Two numerical examples are presented to illustrate the integrated model. The results show that the practical lifespan adoption of machining tools has significant impact on the whole quantity of procurement, and eventually influences the coordinating economic decision making.     

Synthesis and Characterization of High-Quality Polycrystalline Sample NiV2O6 by Solid-State Reaction Technique

Physics of the Solid State - Employing the solid-state reaction route, good quality polycrystalline sample NiV2O6 is prepared that has effective application in rechargeable Li-ion batteries. The...     

Arbutin: Occurrence in Plants,and Its Potential as an Anticancer Agent

Arbutin, a hydroquinone glucoside, has been detected in ca. 50 plant families, especially in the plants of the Asteraceae, Ericaceae, Proteaceae and Rosaceae families. It is one of the most widely used natural skin-whitening agents. In addition to its skin whitening property, arbutin possesses other therapeutically relevant biological properties, e.g., antioxidant, antimicrobial and anti-inflammatory, as well as anticancer potential. This review presents, for the first time, a comprehensive overview of the distribution of arbutin in the plant kingdom and critically appraises its therapeutic potential as an anticancer agent based on the literature published until the end of August 2022, accessed via several databases, e.g., Web of Science, Science Direct, Dictionary of Natural Products, PubMed and Google Scholar. The keywords used in the search were arbutin, cancer, anticancer, distribution and hydroquinone. Published outputs suggest that arbutin has potential anticancer properties against bladder, bone, brain, breast, cervix, colon, liver, prostate and skin cancers and a low level of acute or chronic toxicity.     

Cyclic Scheduling for a Multi-product,Single-facility Production System Operating Under a Just-in-time Delivery Policy

Sarker and Parija have developed a model for obtaining the optimal batch size for a single-product manufacturing system operating under a fixed-quantity, periodic delivery policy. In this work, the model is extended to a multi-product situation and a single-facility scheduling scheme is developed for the system. Two situations are considered—one with fixed setup cost and the other with variable setup cost. It is observed that setup cost variability is beneficial to the system under certain conditions.     

Measuring matrix-based cell formation with alternative routings

A good measure is necessary to evaluate the goodness of grouping in cellular manufacturing. For simple group technology (GT) problems, there are some grouping measures available, the most cited ones are grouping efficiency and grouping efficacy. A grouping measure, which considers alternative routings, is not available for the generalised GT problems. In this paper a new measure called alternative routing grouping (ARG) efficiency is proposed and its desirable properties are derived. Not only can this alternative routing grouping efficiency be used in the generalised GT problems, but it can also be used in the simple GT problems. The computation of the alternative routing grouping efficiency is illustrated with examples, and results of empirical tests on a set of known problems are also reported in this paper. The alternative routing grouping efficiency is extended to the simple GT measures. Grouping efficiency suffers from a weak discriminating capability and grouping efficacy has relatively a better discriminating capability. It is proved that the ARG efficiency has better discriminating capability than the existing measures, and this measure can evaluate the effectiveness of grouping in both simple and generalised cell formation problems with alternative process plans.     

Isolation, Structure Elucidation, and Biological Activity of Flavone 6-C-Glycosides from Alliaria petiolata

Preparative reversed-phase HPLC analysis of a methanol extract of the seeds of Alliaria petiolata afforded fourflavone 6-C-glycosides: isoorientin, swertiajaponin, swertisin and isoscoparin-2--D-glucopyranoside. The molecular structures were elucidated by UV, ESIMS and comprehensive 1D (¹H and ¹³ C) and 2D (gradient multiple quantum filtered ¹H-¹H COSY, ¹H-¹³C HSQC and ¹H-¹³C HMBC) NMR analyses. The antibacterial and free radical scavenging activity, and general toxicity of these compounds were assessed. While none of these glycosides showed any significant antibacterial activities at test concentrations, all these compounds showed prominent free radical scavenging activity (IC₅₀ values: 1.25×10^-2 to 7.69×10^-3 mg/mL) in DPPH assay. In the brine shrimp lethality assay very low levels of general toxicity (LD₅₀ >1.00 mg/mL) were displayed.     

Reaction of oxalyl and malonyl chloride with 1,1-dimethyl-2-substituted hydrazides

Recently we reported the reaction of 1,1-dimethyl-4-substituted semicarbazides with phosgene to occur with formation of several new heterocyclic ring systems. Here we report the reaction of several semicarbazides, thiosemicarbazides and related acyl substituted hydrazides with oxalyl chloride and malonyl chloride. These reactions occur with the formation of heterocyclic products which are oxadiazolinones, imidazolidinetriones, 2-thioxoimidazolindine-4,5-diones, and 2-thioxo-1,3-diazine-4,6-diones (2-thioxopyrimidine-4,6-diones).     

Synthesis,Antimicrobial, Anticancer,PASS, Molecular Docking,Molecular Dynamic Simulations & Pharmacokinetic Predictions of Some Methyl β-D-Galactopyranoside Analogs

A series of methyl β-D-galactopyranoside (MGP, 1) analogs were selectively acylated with cinnamoyl chloride in anhydrous N,N-dimethylformamide/triethylamine to yield 6-O-substitution products, which was subsequently converted into 2,3,4-tri-O-acyl analogs with different acyl halides. Analysis of the physicochemical, elemental, and spectroscopic data of these analogs revealed their chemical structures. In vitro antimicrobial testing against five bacteria and two fungi and the prediction of activity spectra for substances (PASS) showed promising antifungal functionality comparing to their antibacterial activities. Minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) tests were conducted for four compounds (4, 5, 6, and 9) based on their activity. MTT assay showed low antiproliferative activity of compound 9 against Ehrlich’s ascites carcinoma (EAC) cells with an IC₅₀ value of 2961.06 µg/mL. Density functional theory (DFT) was used to calculate the thermodynamic and physicochemical properties whereas molecular docking identified potential inhibitors of the SARS-CoV-2 main protease (6Y84). A 150-ns molecular dynamics simulation study revealed the stable conformation and binding patterns in a stimulating environment. In-silico ADMET study suggested all the designed molecules to be non-carcinogenic, with low aquatic and non-aquatic toxicity. In summary, all these antimicrobial, anticancer and in silico studies revealed that newly synthesized MGP analogs possess promising antiviral activity, to serve as a therapeutic target for COVID-19.