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The purpose of this research was to create bio-based non-isocyanate polyurethane (Bio-NIPU) resins derived from the tannin of Acacia mangium Willd. bark for the impregnation of ramie fibres (Boehmeria nivea L.) and to investigate the properties of impregnated fibres. Tannin was extracted from the bark of A. mangium using hot water. Tannin-bio-NIPU resin was created using dimethyl carbonate and hexamine. Based on the findings, it is possible to conclude that tannin extract from the bark of Acacia mangium can be used effectively as a renewable alternative to toxic polyols in the development of tannin-Bio-NIPU resins. FTIR spectroscopy was used to confirm the urethane bond formed on the tannin-Bio-NIPU resins. Thermal and mechanical analysis were used to investigate the properties of tannin-Bio-NIPU resins and ramie fibres before and after impregnation. This study shows that the impregnation time of ramie fiber using tannin-Bio-NIPU resins is 30 minutes. The reaction between tannin-Bio-NIPU resins with ramie fiber forms the C=O urethane group as confirmed by FTIR Spectroscopy. The characterization results show that tannin-Bio-NIPU resins has ability to modify ramie fiber via impregnation in order to increase its mechanical properties, thus enhancing its potential for wider industrial application as a functional material.

The current study examines an essential type of vehicle routing problem (VRP). This type is one where customers are served by limited-capacity vehicles from multiple depots and is known as Multi-Depot Capacitated Vehicle Routing Problem (MDCVRP). The novelty of this study is that in the present case, cars, after Leaving the Depot, can go back to any other depot. Those issues seem to occur in most real-world issues where information, messages, or news are sent electronically from somewhere. The purpose of the problem is to minimize the costs associated with routing. Regarding the literature on such issues, it has been proven in previous studies and research that these problems are among the hard-NP problems, and to solve them using the metaheuristic method, the exact methods justify it. After changing the basic model, this study developed a Tabu Search (TS) algorithm. The study results demonstrate that if the equipment can return to any depot, the cost is significantly reduced in contrast to the case where equipment is forced to return to their depot.

Recently, utilizing appropriate inventory control policy and determining the optimal selling price for various goods has been the main topic of scientific and industrial research. Inventory management policy 1 by the seller is one solution that improves the chain’s performance by creating coordination between members of the supply chain. The current study attempts to devise an integrated model of inventory pricing and control under the inventory management policy by the seller for perishable goods with shortages is considered. The purpose of presenting the model is to determine the optimal price, the optimal repayment time, and the order size, in order to maximize the profit. To acquire those optimal values, the profit functions of the buyer and the seller are taken into account. Given the results acquired, it is demonstrated that at any cost, the repayment time is unique and optimal. It is concluded that with the optimal recovery time available, the objective function is a concave function of price, and its optimal value is available. Furthermore, utilizing the inventory management policy by the seller could be a proper means to reducing retailer costs while raising their profit.

With the globalization of markets and increasing competition in global markets, the attempts of organizations to survive in this market has increased and has resulted in the emergence of the philosophy of Supply Chain Management. There is uncertainty in the reliability of supply chain facilities for reasons such as natural disasters, terrorist attacks, labor errors, and weather conditions. Therefore, when making strategic decisions, the system will continue to operate with minimal damage. Over the course of this study, the uncertainty of supplier layers in the supply chain has been modeled. To meet that aim, the issue of supply chain, including producers, warehouses, suppliers and consumers are considered. To calculate the cost of breakdowns due to the non-functioning of distributors, the scenario-building method has been utilized. Finally, the desired model is solved with Gomez software and the results are presented. The result of the study demonstrate the efficiency of this model in the facility location decision-making in supply chains.

One of the adverse effects of industrialization is noise pollution, which disturbs the mental health and tranquility of urban residents and is the source of numerous social tensions. Twenty stations in the central areas of Almaty with varying uses during the morning, afternoon, and evening rush hours were measured for this study. The objectives of this paper include determining sound indices, identifying potential sound sources, and calculating the relative contribution of each to the overall urban noise level. Additionally, 400 questionnaires were distributed to individuals to assess noise pollution’s effects on individuals. The average maximum value of TNI (Traffic Noise Index) in residential and commercial use is 85.4 dB(A), and the maximum value of Leq (Equivalent continuous sound level) in commercial use is 86 dB(A). In addition, 50 city bus drivers were examined to determine the impact of noise in this environment. The results revealed that as Leq increases, the number of unsafe acts increases. The questionnaires revealed that people are significantly more dissatisfied with noise pollution at stations with higher sound levels.

Noise pollution is one of the environmental factors that severely threaten humans’ mental, emotional, and physical health. One of the most significant sources of this pollution is the noise generated by traffic and urban transportation, mainly the urban railway. This paper assessed noise pollution at stations, passenger cars, and the train operator’s cabin. Four consecutive Baghdad subway stations were used to collect information. There were three modes of measurement: entering the station, stopping at the station, and leaving the station. Leq (equivalent continuous noise level) at station 3 is more significant than at three other stations, confirming that the initial hypothesis regarding the noise pollution rate was correct. Among the studied stations, Station 1 was the quietest. The stations with the highest and lowest Leq values are 3 and 2, respectively. The Leq values recorded in the cabin are within the permissible range. The highest Leq value measured at station 3 is 81.87 dB(A), and the lowest Leq value measured at station 2 is 61.24 dB(A). The operator’s cabin at station 3 has the highest measured Leq of 70.26 dB(A), and station 1 has the lowest measured Leq of 61.5 dB(A). While the measured value in the operator’s cabin was within the acceptable range, the noise levels in the wagons were above standard.

Over the course of the last decades, closed-loop supply chains (CLSC) and reverse logistics issues have attracted increasing attention owing to strict environmental laws, social responsibilities, economic interests, and customer awareness. Hence, the issue of closed-loop supply chain and reverse logistics has emerged as a field of research in the new era. This issue has received much attention because it allows recyclable products to return to their original cycle. Therefore, this study primarily intends to present a mathematical model for designing a supply chain network for recycled products. The multi-stage and multi-period objective function of the closed-loop supply chain is presented to meet that aim. In this chain, dismantling, recycling, and disposal centers are considered. The objective function is to reduce the total cost of the closed-loop supply chain. The results of optimizing the mathematical model demonstrate that this model has the necessary efficiency for use in recycled products.

In recent years, the increase in population and the decrease in agricultural lands and water shortages have caused many problems for agriculture and farmers. That is why scheduling is so important for farmers. Therefore, the implementation of an optimal schedule will lead to better use of agricultural land, reduce water consumption in agriculture, increase efficiency and quality of agricultural products. In this research, a scheduling problem for harvesting agricultural products has been investigated. In this problem, there are n number of agricultural lands that in each land m agricultural operations are performed by a number of machines that have different characteristics. This problem is modeled as a scheduling problem in a flexible workshop flow environment that aims to minimize the maximum completion time of agricultural land. The problem is solved by programming an integer linear number using Gams software. The results show that the proposed mathematical model is only capable of solving small and medium-sized problems, and due to the Hard-NP nature of the problem, large-scale software is not able to achieve the optimal solution.

This study focused on energy saving in energy hub system using smart grid technologies and management of the energy demand. The two-layer energy management is proposed for implementing energy saving. In first layer, energy demand such as electrical, thermal and natural gas are optimized subject to optimal level of the demand at day-ahead. Then, optimized energy demand is applied in second layer to reduction energy generation costs. The optimization of the proposed approach is done by shuffled frog leaping algorithm (SFLA), and results at several case studies to confirmation of the proposed approach are investigated.

In this paper, a multi objective optimization approach is studied for optimal energy scheduling of the smart autonomous electrical grid with participation of active consumers (ACs) and hydrogen storage system (HSS). The objective functions consist of: 1) minimizing the costs and 2) maximizing reliability. The ACs participation are modelled through demand reduction approach based on offer price to peak demand management. The proposed optimization is solved by epsilon-constraint method and LINMAP decision making strategy. The 21-node test system is employed to analyse the efficiency of the proposed approach at two case studies. The obtained results shown the high effectiveness of smart autonomous electrical grid with participation of ACs and HSS to supply the demand.

Lignin, lignosulfonate, and synthesized phosphorylated lignosulfonate were introduced as green fillers in citric acid-sucrose adhesives for bonding particleboard fabricated from areca leaf sheath (ALS). The characteristics of particleboards were compared to that of ultralow emitting formaldehyde (ULEF-UF). The fillers derived from Eucalyptus spp. kraft-lignin were added for flame retardancy enhancement. 10% of each lignin and modified lignin was added into the ULEF-UF and citric acid-sucrose bonded particleboards. Analyses applied to particleboards included thermal characteristics, X-ray diffraction analysis (XRD), morphological properties, Fourier transform infrared spectroscopy (FTIR), as well as physical, mechanical, and fire resistance characteristics of the laboratory-fabricated particleboards. Lignin and modified lignin resulted in improved thermal stability of the composites bonded with ULEF-UF while the improvement in the particleboard bonded with citric acid-sucrose was not significant. The introduction of filler exerted a higher influence on the UF-bonded particleboards compared to composites fabricated with citric acid-sucrose. Generally, the presence of lignin, lignosulfonate, and phosphorylated lignosulfonate enhanced the mechanical strength of the ULEF-bonded particleboards, although their dimensional stability has deteriorated. Markedly, the use of lignin and lignosulfonate enhanced the fire resistance of the particleboards produced with lower observed weight loss. All laboratory particleboards exhibited satisfactory fire resistance, attaining a V-0 rating in according to the UL-94 standard. [ABSTRACT FROM AUTHOR]

More than a century after its initial synthesis, urea-formaldehyde (UF) resins still have dominant applications as adhesives, paints, and coatings. However, formaldehyde in this industry produces formaldehyde emissions that are dangerous to health. Scientists have spent the last decade replacing formaldehyde and phenol with environmentally friendly substances such as glyoxal and tannin to create bio-based adhesives. This review covers recent advances in synthesizing glyoxal tannin-based resins, especially those made from sustainable raw material substitutes and changes made to synthetic processes to improve mechanical properties. The efficacy of using tannin-glyoxal adhesives in producing wood-based composites has been proven. The glyoxylate reaction forms cross-linked bridges between the aromatic sites of the tannin and glyoxal molecular structures. Glyoxal tannin adhesive with a greater percentage of glyoxal than tannin will produce an adhesive with better characteristics. The gel time reduces as the hardener concentration rises from 7.5% to 15% when glyoxal is used in adhesives. However, excessive amounts of glyoxal will result in a decrease in viscosity values. Glyoxal exhibits faster delivery degradation when it reaches a maximum temperature of approximately 130°C, although it initiates the curing process slightly slower at 110°C. Adding glyoxal to tannin-based adhesives can improve the mechanical properties of composite boards. The wet shear strength of the resulting plywood is increased by 105.4% with the addition of 5-weight percent tannin-based resin with glyoxal as a cross-linker in Soy Protein Adhesive. With glyoxal as a hardener, the panels produced showed good internal bond strengths (>0.35 MPa) and met the international standard specifications for interior-grade panels. [ABSTRACT FROM AUTHOR]

This study aimed to analyze the effect of pre-heat treatment on bamboo strand properties and its impact on the properties of the resulting bamboo-oriented strand board (BOSB). Giant bamboo (Dendrocalamus asper (Schult.) Backer) with a density of 0.53 g cm−3 was converted into bamboo strands. These strands were pre-heat-treated at 140 and 160 °C for a duration of 1, 2, and 3 h. Changes in the chemical composition of the strand due to subsequent treatment were assessed. Fourier-transform infrared spectroscopy (FTIR) and X-Ray diffraction analysis (XRD) were used to determine the changes in the chemical composition of bamboo strands. The BOSB panels were produced with a target density of 0.7 g cm−3. The manufacturing of the BOSB was conducted in three layers with a ratio of 25:50:25, bonded with phenol-formaldehyde resin. The physical and mechanical properties of the laboratory-fabricated BOSB were tested in compliance with the criteria given in JIS A 5908 standards. Comparisons were made against OSB CSA 0437.0 Grade O-1 commercial standard. The pre-heat treatment led to chemical alterations within the material when set at 140 and 160 °C for 1 to 3 hours (h). FTIR spectral analysis demonstrated that longer exposure and higher temperatures resulted in fewer functional groups within the bamboo strands. The increased temperature and duration of pre-heat treatment enhanced the crystallinity index (CI). The dimensional stability and mechanical properties of the composites were improved significantly as hemicellulose and extractive content were reduced. This study demonstrated that the pre-heat treatment of bamboo strands at a temperature of 160 °C for a duration of 1 h was an adequate approach for heat modification and fabrication of BOSB panels with acceptable properties according to OSB CSA 0437.0 Grade O-1 commercial standard. [ABSTRACT FROM AUTHOR]

Early diagnosis of hepatocellular carcinoma (HCC), a leading cause of cancer mortality, is decisive for successful treatment of this type of cancer and increasing the patients' survival rate. Alpha-fetoprotein (AFP) is a glycoprotein that has been currently employed as a potential serological biomarker for determination of HCC and several other cancers. Achieving highly sensitive and specific detection of this biomarker is an effective strategy to inhibit developing issues caused by the cancer. Though, traditional procedures cannot meet the requirements due to the technical drawbacks. Recently, growing number of aptamer-based biosensors (aptasensors) attracted important attention as superior diagnostic tools because of their unique properties such as high stability, target versatility and remarkable affinity and selectivity. Nanomaterials, which broadly employed in the structure of these aptasensors, can considerably enhance the detection limit and sensitivity of analytes determination. Therefore, this review selectively investigated the recent progresses in several different optical and electrochemical aptasensors and nano-aptasensors designed for AFP assay. [ABSTRACT FROM AUTHOR]