Developing trust among players in a vendor-managed inventory model for random demand under environmental impact.

Retailers play a vital role in supply chain management because they deal directly with consumers. Occasionally, retailers may cover the entire system's statistics and not disclose these data to the manufacturer. Therefore, asymmetry is generated in the data throughout the system. The main motive of this research was to prevent unreliability throughout the system using a vendor-managed inventory policy. This research shows that by applying a cap and trade policy, the total carbon emitted from the production and transportation sectors can be controlled in the atmosphere. Finally, numerical and sensitivity analyses, along with pictorial representations of various parameters, are performed to examine the optimal results of this study. In addition, the retailer's lead time demand for items is assumed to be random rather than fixed and follows uniform and normal distribution functions. Under these two distribution functions, the optimal retailer lot size, service provided by the retailer to customers, and retailer reorder points are assessed. Furthermore, an evaluation of the total carbon released from an environmental viewpoint is illustrated using numerical findings. The numerical results show that this research is 50.24% more economically beneficial than the methods used in previous studies, whereas the mean value of demand follows a uniform distribution.

A sustainable smart production model for partial outsourcing and reworking.

Smart production plays a significant role to maintain good business terms among supply chain players in different situations. Adjustment in production uptime is possible because of the smart production system. The management may need to reduce production uptime to deliver products ontime. But, a decrement in production uptime reduces the projected production quantity. Then, the management uses a limited investment for pursuing possible alternatives to maintain production schedules and the quality of products. This present study develops a mathematical model for a smart production system with partial outsourcing and reworking. The market demand for the product is price dependent. The study aims to maximize the total profit of the production system. Even in a smart production system, defective production rate may be less but unavoidable. Those defective products are repairable. The model is solved by classical optimization. Results show that the application of a variable production rate of the smart production for variable market demand has a higher profit than a traditional production (52.65%) and constant demand (12.45%).

Electrochemical C-H Sulfonylation of Hydrazones.

We have developed an electrochemical method for the direct C-H sulfonylation of aldehyde hydrazones using sodium sufinates as the sulfonylating agent under supporting electrolyte-free conditions. This straightforward sulfonylation strategy afforded a library of (E)-sufonylated hydrazones with high tolerance of various functional groups. The radical pathway of this reaction has been revealed by the mechanistic studies.

Demand-induced regime shift in fishery: A mathematical perspective.

Though overfishing and climate change are the primary reasons for a regime shift in the fishery, we demonstrate here a different reason for the regime shift, not reported earlier to the best of our knowledge. We show that high demand for fish may cause a regime shift in a fishery in a shorter time. For this, a four-dimensional bioeconomic fishery model is considered and analyzed to explore the system's dynamic behavior. The objective is to demonstrate how increasing demand may cause a catastrophic change in the fish and fishery. We provide the local and global stabilities of different equilibrium points, guaranteeing the stable coexistence of ecological and economic states. Our bifurcation analysis revealed that the demand parameter might play positive and negative roles in the system dynamics. Demand can make an unstable fishery stable. It can also help remove the infection from the system. On the flip side, high demand may cause a regime shift from a harvested state to a non-harvested state, making the price unbounded. Using Pontryagin's maximum principle, we further discussed optimal revenue generation.

A distribution-free newsvendor model considering environmental impact and shortages with price-dependent stochastic demand.

In today's competitive and volatile market, demand prediction for seasonal items is a challenging task. The variation in demand is so quick that the retailer cannot face the risk of understocking or overstocking. Unsold items need to discarded, which has environmental implications. It is often difficult to calculate the effects of lost sales on a firm's monetary values, and environmental impact is not a concern to most businesses. These issues concerned with the environmental impact and the shortages are considered in this paper. A single-period inventory mathematical model is formulated to maximize expected profit in a stochastic scenario while calculating the optimal price and order quantity. The demand considered in this model is price-dependent, with several emergency backordering options to overcome the shortages. The demand probability distribution is unknown to the newsvendor problem. The only available demand data are the mean and standard deviation. In this model, the distribution-free method is applied. A numerical example is provided to demonstrate the model's applicability. To prove that this model is robust, sensitivity analysis is performed.

Logistic models to minimize the material handling cost within a cross-dock.

Retail supply chains are intended to empower effectiveness, speed, and cost-savings, guaranteeing that items get to the end client brilliantly, giving rise to the new logistic strategy of cross-docking. Cross-docking popularity depends heavily on properly executing operational-level policies like assigning doors to trucks or handling resources to doors. This paper proposes a linear programming model based on door-to-storage assignment. The model aims to optimize the material handling cost within a cross-dock when goods are unloaded and transferred from the dock area to the storage area. A fraction of the products unloaded at the incoming gates is assigned to different storage zones depending on their demand frequency and the loading sequence. Numerical example considering a varying number of inbound cars, doors, products, and storage areas is analyzed, and the result proves that the cost can be minimized or savings can be intensified based on the feasibility of the research problem. The result explains that a variation in the number of inbound trucks, product quantity, and per-pallet handling prices influences the net material handling cost. However, it remains unaffected by the alteration in the number of material handling resources. The result also verifies that applying direct transfer of product through cross-docking is economical as fewer products in storage reduce the handling cost.

Aza-Michael promoted glycoconjugation of PETIM dendrimers and selectivity in mycobacterial growth inhibitions.

The benign nature of aza-Michael addition reaction in aqueous solutions is demonstrated herein to conduct a direct glycoconjugation of amine-terminated poly(ether imine) (PETIM) dendrimers. Zero to three generations of dendrimers, possessing up to 16 amine functionalities at their peripheries, undergo aza-Michael reaction with unsaturated sugar vinyl sulfoxide in aq. MeOH solutions and afford the corresponding dendrimers modified with multiple glycosyl moieties at the periphery. First order kinetics of the glycoconjugation is monitored at varying temperatures and the rate constants are observed to be 60-508 s-1, for zero and first generation dendrimers. The antibacterial effects of amine-terminated dendrimers and the corresponding glycoconjugates are studied across Gram-positive, Gram-negative and acid-fast bacteria. Among the species, M. smegmatis and M. tuberculosis showed the greatest growth inhibition effect at micromolar concentrations, for the native amine-terminated and the corresponding glycoconjugated dendrimers. Quantitative assays are performed to adjudge the inhibition efficacies of dendrimers and the glycoconjugates. Selectivity to inhibit M. smegmatis and M. tuberculosis growth, and minimal effects on other bacterial species by dendrimers and glycoconjugates are emphasized.

Product outsourcing policy for a sustainable flexible manufacturing system with reworking and green investment.

Production of defective products is a very general phenomenon. But backorder and shortages occur due to this defective product, and it hampers the manufacturer's reputation along with customer satisfaction. That is why, these outsourced products supply, a portion of required products for in-line production. This study develops a flexible production model that reworks repairable defective products and outsources products to prevent backlogging. A percentage of total in-line production is defective products, which is random, and those defective products are repairable. A green investment helps the reworking process, which has a direct impact on the market demand for products. A classical optimization solves the profit maximization model, and a numerical method proves the global optimal solutions. Sensitivity analysis, managerial insights, and discussions provide the highlights and decision-making strategies for the applicability of this model.

Cyclic Disaccharide Formation Enforced by a Ring Contraction: 2,3-Dideoxy Pyranoside Glycoside Donor to a Furanoside Macrocycle.

The synthesis of a disaccharide macrocycle through 2,3-dideoxy glucopyranosyl monosaccharide is reported. 2,3-Dideoxy-erythro-hexopyranosyl thioglycoside possessing a free hydroxy functionality at the C-4 carbon is prepared, and cycloglycosylation is conducted. In the event, the cycloglycosylation occurs with a ring contraction of the monosaccharide moiety and affords the cyclic furanoside disaccharide. Solution-phase and single-crystal X-ray diffraction structural characterizations permit the features of the macrocycle to be uncovered. The solubilization and encapsulation properties of the macrocycle are studied in aqueous solutions with 1-aminoadamantane.

Mathematical estimation for maximum flow of goods within a cross-dock to reduce inventory.

Supply chain management has recently renovated its strategy by implementing a cross-docking scheme. Cross-docking is a calculated logistics strategy where freight emptied from inbound vehicles is handled straightforwardly onto outbound vehicles, eliminating the intermediate storage process. The cross-docking approach thrives on the minimum storage time of goods in the inventory. Most of the cross-docks avail temporary storage docks where items can be stored for up to 24 hours before being packed up for transportation. The storage capacity of the cross-dock varies depending on the nature of ownership. In the rented cross-docks center, the temporary storage docks are considered of infinite capacity. This study believes that the temporary storage facilities owned by the cross-dock center are of finite capacity, which subsequently affects the waiting time of the goods. The flow rate of goods within the cross-docks is expected to be maximum to avoid long waiting for goods in the queue. This paper uses a series of max-flow algorithms, namely Ford Fulkerson, Edmond Karp, and Dinic's, to optimize the flow of goods between the inbound port and the outbound dock and present a logical explanation to reduce the waiting time of the trucks. A numerical example is analyzed to prove the efficacity of the algorithm in finding maximum flow. The result demonstrates that Dinic's algorithm performs better than the Ford Fulkerson and Edmond Karp algorithm at addressing the problem of maximum flow at the cross-dock. The algorithm effectively provided the best result regarding iteration and time complexity. In addition, it also suggested the bottleneck paths of the network in determining the maximum flow.

Phycoremediation of pollutants from secondary treated coke-oven wastewater using poultry litter as nutrient source: a cost-effective polishing technique.

This article focuses on the phycoremediation of pollutants from secondary treated coke-oven effluent through a green and economical route. A microalgal sample was collected and identified as a consortium of Chlorella sp. and Synechococcus sp. The culture cost was reduced by using poultry litter extract as supplementary material to BG-11 medium. Since the major pollutants present in real secondary treated coke-oven wastewater are phenol, ammoniacal-N (NH4+) and cyanide, several matrices were designed with these three major pollutants by varying their initial concentrations such as phenol (2-10 mg/L), cyanide (0.3-1 mg/L) and NH4+ (100-200 mg/L), termed as simulated secondary treated coke-oven wastewater. Maximum removal was observed with individual solutions of phenol (4 mg/L), cyanide (0.6 mg/L) and NH4+ (175 mg/L), while maximum removal in simulated secondary treated coke-oven wastewater was observed at higher concentrations of phenol (8 mg/L) and cyanide (0.8 mg/L) and the same concentration of NH4+ (175 mg/L). A consortium was found effective to meet statutory limits of pollutants. Kinetic model was developed for predicting growth of consortium and observed that the poultry litter extract-enriched BG-11 medium showed higher values of maximum specific growth rate (0.56 per day) and carrying capacity (1,330 mg/L) than that in BG-11 medium only.

Glycoconjugations of Biomolecules by Chemical Methods.

Bioconjugations under benign aqueous conditions have the most promise to covalently link carbohydrates onto chosen molecular and macromolecular scaffolds. Chemical methodologies relying on C-C and C-heteroatom bond formations are the methods of choice, coupled with the reaction conditions being under aqueous milieu. A number of methods, including metal-mediated, as well as metal-free azide-alkyne cyclo-addition, photocatalyzed thiol-ene reaction, amidation, reductive amination, disulfide bond formation, conjugate addition, nucleophilic addition to vinyl sulfones and vinyl sulfoxides, native chemical ligation, Staudinger ligation, olefin metathesis, and Suzuki-Miyaura cross coupling reactions have been developed, in efforts to conduct glycoconjugation of chosen molecular and biomolecular structures. Within these, many methods require pre-functionalization of the scaffolds, whereas methods that do not require such pre-functionalization continue to be few and far between. The compilation covers synthetic methodology development for carbohydrate conjugation onto biomolecular and biomacromolecular scaffolds. The importance of such glycoconjugations on the functional properties is also covered.

Disruption management in a constrained multi-product imperfect production system.

Over several decades, production and inventory systems have been widely studied in different aspects, but only a few studies have considered the production disruption problem. In production systems, the production may be disrupted by priorly unknown disturbance and the entire manufacturing plan can be distorted. This research introduces a production-disruption model for a multi-product single-stage production-inventory system. First, a mathematical model for the multi-item production-inventory system is developed to maximize the total profit for a single-disruption recovery-time window. The main objective of the proposed model is to obtain the optimal manufacturing batch size for multi-item in the recovery time window so that the total profit is maximized. To maintain the matter of multi-product, budget and space constraints are used. A genetic algorithm and pattern search techniques are employed to solve this model and all randomly generated test results are compared. Some numerical examples and sensitivity analysis are given to explain the effectiveness and advantages of the proposed model. This proposed model offers a recovery plan for managers and decision-makers to make accurate and effective decisions in real time during the production disruption problems.

Sugar Vinyl Sulfoxide Glycoconjugation of Peptides and Lysozyme: Abrogation of Proteolysis at the Lysine Sites.

We describe a glycoconjugation strategy in which a sugar vinyl sulfoxide, acting as Michael donor, reacts efficiently with amine nucleophiles arising from the lysine side chain in peptides and proteins, at physiological pH and temperature. The method permits glycoconjugation of the lysine residues present in lysozyme with the sugar vinyl sulfoxide. The glycoconjugation of the protein abrogates the trypsin-mediated proteolysis at the lysine sites. The modified protein catalyzes digestion of the Gram-negative Escherichia coli cell wall and retains the same antimicrobial property as the native lysozyme.

Simultaneous removal of Cd (II) and p-cresol from wastewater by micellar-enhanced ultrafiltration using rhamnolipid: Flux decline, adsorption kinetics and isotherm studies.

Flux decline due to membrane fouling by surfactant micelles is the major problem limiting the use of micellar enhanced ultrafiltration (MEUF) for the treatment of wastewater. Understanding of underlying mechanisms of membrane fouling, adsorption kinetics and adsorption isotherm are very important for the successful application of MEUF studies. In the present study, an unsteady state model considering sequential occurrence of complete pore blocking and gel layer formation was proposed for explaining flux decline behavior during rhamnolipid based MEUF for simultaneous removal of Cd+2 and p-cresol from aqueous solution under batch concentration mode. The model was developed based on the Hermia's complete pore blocking model and resistance-in-series model coupled with gel layer theory incorporating the effects of feed temperature, variation of viscosity and retentate concentration with time, and pressure dependent mass transfer coefficient. A good agreement between the experimental data and model predictions was demonstrated. The effects of operating conditions were found to have a significant effect on the flux decline behavior and onset of gel layer formation. The use of ultrafiltration membrane for the study of adsorption kinetics and adsorption isotherm was demonstrated. Kinetic studies disclosed that both Cd+2 and p-cresol adsorption was better described by the pseudo-second order model for both single and binary solution. The results of isotherm studies revealed that adsorption of both Cd+2 and p-cresol was spontaneous in nature and equilibrium data was best fitted by Langmuir model with the maximum adsorption capacity of RHL vesicles of 208.33 and 53.27 mg g-1 for Cd+2 and p-cresol, respectively at 299 K. The model parameters of membrane fouling, adsorption kinetics and adsorption isotherm evaluated in this study could be useful in designing and scale up of RHL based MEUF process.

Adsorption of poly(ethylene oxide)-containing amphiphilic polymers on solid-liquid interfaces: Fundamentals and applications.

The adsorption of amphiphilic molecules of varying size on solid-liquid interfaces modulates the properties of colloidal systems. Nonionic, poly(ethylene oxide) (PEO)-based amphiphilic molecules are particularly useful because of their graded hydrophobic-hydrophilic nature, which allows for adsorption on a wide array of solid surfaces. Their adsorption also results in other useful properties, such as responsiveness to external stimuli and solubilization of hydrophobic compounds. This review focuses on the adsorption properties of PEO-based amphiphiles, beginning with a discussion of fundamental concepts pertaining to the adsorption of macromolecules on solid-liquid interfaces, and more specifically the adsorption of PEO homopolymers. The main portion of the review highlights studies on factors affecting the adsorption and surface self-assembly of PEO-PPO-PEO block copolymers, where PPO is poly(propylene oxide). Block copolymers of this type are commercially available and of interest in several fields, due to their low toxicity and compatibility in aqueous systems. Examples of applications relevant to the interfacial behavior of PEO-PPO-PEO block copolymers are paints and coatings, detergents, filtration, and drug delivery. The methods discussed herein for manipulating the adsorption properties of PEO-PPO-PEO are emphasized for their ability to shed light on molecular interactions at interfaces. Knowledge of these interactions guides the formulation of novel materials with useful mesoscale organization and micro- and macrophase properties.

Completeness and regularity of generalized fuzzy graphs.

Fuzzy graphs are the backbone of many real systems like networks, image, scheduling, etc. But, due to some restriction on edges, fuzzy graphs are limited to represent for some systems. Generalized fuzzy graphs are appropriate to avoid such restrictions. In this study generalized fuzzy graphs are introduced. In this study, matrix representation of generalized fuzzy graphs is described. Completeness and regularity are two important parameters of graph theory. Here, regular and complete generalized fuzzy graphs are introduced. Some properties of them are discussed. After that, effective regular graphs are exemplified.

Interval-valued fuzzy [Formula: see text]-tolerance competition graphs.

This paper develops an interval-valued fuzzy [Formula: see text]-tolerance competition graphs which is the extension of basic fuzzy graphs and [Formula: see text] is any real valued function. Interval-valued fuzzy [Formula: see text]-tolerance competition graph is constructed by taking all the fuzzy sets of a fuzzy [Formula: see text]-tolerance competition graph as interval-valued fuzzy sets. Product of two IVFPTCGs and relations between them are defined. Here, some hereditary properties of products of interval-valued fuzzy [Formula: see text]-tolerance competition graphs are represented. Application of interval-valued fuzzy competition graph in image matching is given to illustrate the model.

Nanoparticle surface modification by amphiphilic polymers in aqueous media: role of polar organic solvents.

We investigate the role of three polar organic solvents (dimethyl formamide (DMF), dimethyl sulfoxide (DMSO), and glycerol) on the interfacial behavior of Pluronic P105 poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) block copolymers on protonated silica nanoparticles in an aqueous dispersion. The polymer adsorption and self-assembly have been assessed from critical surface micelle concentration (csmc, measured by pyrene fluorescence spectroscopy) and adsorbed layer thickness (measured by capillary viscometry) data. Above its csmc, PEO-PPO-PEO block copolymers form hydrophobic domains on the nanoparticle surface. Below a critical concentration in water (known as critical displacer concentration, cdc), organic solvents act as displacers (molecules that can displace adsorbed polymer from a solid surface). The critical displacer concentration is obtained from the csmc and the polymer adsorbed layer thickness data. The cdc is found to be dependent on both the amount of nanoparticles present in the system as well as the nature of the displacer. Below the cdc, the csmc increases and the adsorbed polymer layer thickness decreases with increasing organic solvent concentration. Interfacial free energy calculations suggest that DMF, DMSO, and glycerol can adsorb onto the silica particles by displacing adsorbed PEO. These calculations are consistent with the experimental results in that, as a displacer, glycerol is the most effective and DMF is the least effective. Above the cdc, the influence of glycerol or DMSO on csmc is opposite to that of DMF which is attributed to the cosolvent effect.

Micellization of amphiphilic block copolymers in binary and ternary solvent mixtures.

Amphiphilic block copolymers of the poly(ethylene oxide)-poly(propylene oxide) (PEO-PPO) family (commercially available as Pluronics or Poloxamers) are well-known for self-assembling in water (selective solvent for PEO) into micelles with a PPO-rich core and a hydrated PEO corona. The micellization of two PEO-PPO-PEO block copolymers (Pluronic P105: EO(37)PO(56)EO(37) and Pluronic F127: EO(100)PO(65)EO(100)) has been studied in binary mixed solvents consisting of water and one of the following organic solvents: ethanol, glycerol, D(+)-glucose monohydrate, propylene carbonate, or triacetin, and also in ternary mixtures of water with 50/50 wt% ethanol+glycerol or 50/50 wt% ethanol+propylene carbonate. Glycerol, glucose, propylene carbonate and triacetin were found to promote micellization when added to water. Glycerol and glucose interact favorably with water, and reduce the block copolymer critical micelle concentration (cmc) by dehydrating the PEO-PPO interface as well as changing the bulk solvent properties. Propylene carbonate and triacetin act by locating at the PEO-PPO interface and increasing its hydrophobicity. The addition of ethanol to water provides better solvent conditions for the block copolymers compared to plain water, and disfavors the formation of micelles. In the case of ternary solvents consisting of water, ethanol (that prevents micelle formation), and glycerol or propylene carbonate (that favor micelle formation), the observed changes in the cmc are subtle. For Pluronic P105, the cmc increase is greater for ethanol+propylene carbonate (50/50 wt%) than for ethanol+glycerol (50/50 wt%). For Pluronic F127, the cmcs remain the same as in plain water, i.e., the effects of the two organic solvents compensate each other. The difference between the free energy of micellization in plain water and that in solvent mixtures varies linearly with the cosolvent concentration, and collapses into a single line for each solvent mixture type when normalized with the number of the block copolymer PO units (N(PO)), indicating that the micelle core is mainly affected by varying solvent condition for different PEO/PPO ratios.