Economic Goods Research Articles

Experimental research on resource utilization of iron tailings powder in backfilling engineering

The goaf formed by mining and other activities is prone to safety hazards. Preparing high-quality and low-cost solidified iron tailings powder (SITP) is an important way to ensure backfill quality and eliminate safety hazards. Using iron tailings powder near the goaf of in Shanxi, comparative experiments were conducted to evaluate the the flowability, stone rate, strength, and water stability of newly mixed SITP under different types and dosages of curing agent, and mixing methods. The results show that under the premise of keeping the fluidity constant, the strength of the ITP slurry increases with the increase of the curing agent content; At the same strength, the water consumption significantly affects the fluidity; When using 8%~16% different curing agent dosage, the expansion degree is 280 mm ~ 600 mm, the wet density is 1.9 g/cm3 ~ 2.1 g/cm3, the 28d strength after curing is 1.4 MPa ~ 3.7 MPa, and the stone rate is greater than 92%; The ITP slurry prepared by vibration mixing with a mixing time of 120 s and the amount of curing agent at 8% meets the engineering application requirements of 7d strength of 0.6 MPa and expansion of 250 mm. The research shows that the iron tailings powder slurry prepared by vibration mixing has high strength after solidification, and it is a new way of resource utilization of iron tailings powder with large consumption and good economy to be used for goaf backfilling.

Copper-Catalyzed Radical Cascade Cyclization of N-Substituted Indole-3-Aldehydes with Aryl Alkenes: Access to Pyrrolo[1,2-a]indole Scaffolds.

Herein, we report a Cu-DTBP-catalyzed [3 + 2] cycloaddition reaction between 1-(2-oxo-2-phenylethyl)-1H-indole-3-aldehyde and arylalkene, using DMF as the solvent. Under relatively mild reaction conditions, a series of indole compounds were synthesized in moderate yields (up to 73%). This protocol features good functional group tolerance and high atom economy. In addition, we synthesized a total of 20 target compounds, providing a reliable and straightforward method to obtain structurally diverse pyrrolo[1,2-a]indole derivatives.

Construction of an Efficient O-Succinyl-L-homoserine Producing Cell Factory and Its Application for Coupling Production of L-Methionine and Succinic Acid.

O-Succinyl-L-homoserine (OSH) is an important C4 platform compound with broad applications. Its green and efficient production is receiving increasing attention. Herein, the OSH producing chassic cell was constructed by deleting the transcriptional negative regulation factor, blocking the OSH consumption pathway, and inhibiting the competitive bypass pathways. The precursor synthesis pathways of aspartic acid and homoserine were further strengthened, and the pentose phosphate pathway and glycolysis pathway were modified to enhance the NADPH supply. Adaptive evolution was applied to improve the tolerance of the cell factory to the fermentation environment. With Raman online analysis, the metabolic process model was built to guide fermentation regulation. The final titer of OSH reached 121.7 g/L with conversion of 63% in a 50 L fermenter. Based on this, a coupling production route for L-methionine and succinic acid from OSH was established with good atomic economy and environmental friendliness.

Cross-national benchmarking and acceptance of pandemic mitigation policies: human value approach

PurposeThis study analyzes the reasons for satisfaction or dissatisfaction among people with public health mitigation policies, particularly with focus on human values. Recent studies reveal that the citizenry of various nations reacted to government policy measures differently when asked if they are satisfied with government handling of COVID-19. Human values such as openness-to-change and conservation might influence the acceptance of pandemic mitigation measures.Design/methodology/approachA structural equation model (SEM) is proposed, which incorporates mitigation strategies and human value variables. National health survey data of the COVID-19 pandemic in Great Britain and Italy is used to test several hypotheses.FindingsThe model analysis suggests that prioritizing public health, monitoring and tracking people, border closures and restricting people’s movement played important roles in the satisfaction of government handling of the COVID-19 pandemic. Individuals with a high conservation value are more likely to have a higher probability of dissatisfaction with the government’s handling of COVID-19 pandemic. During a pandemic, the citizens are more willing to trade a good economy for public health. They are also more willing to sacrifice privacy in the government’s efforts to track the spread.Originality/valueThis is a unique study which combines human value variables and mitigation policies in determining acceptance of government policies among citizenry during national health crisis. A SEM modeling framework is presented to analyze empirically several hypotheses.

Stochastic Inflation and the Term Structure of Interest Rates: a Simple Diffusion Model

Abstract The present paper addressesthe problem of valuing contingent claims on the term structure in a single good economy under uncertain inflation. In the context of arbitrage-free valuation, a simple diffusion model for pricing inflation -indexed securities is proposed. A martingale characterization of nominal and real prices is given and a stochastic generalization of the Fisher equation is provided. An example of two-factor model which can be used to value inflation-linked securitiesin practical applications, is also discussed. JEL classification numbers: G00, G10, G30. Keywords: Term structure of interest rates, Fisher equation, HJM-methodology, Inflation-linked securities.

Study on Collision Dynamics Similarity of Thickness Distortion Model of Train Five-Hole Thin-Walled Structure

Full-scale train collision tests are rarely carried out because of high cost, but small-scale model tests have good economy and repeatability, providing a new research method for train crashworthiness design. The metal thin-walled tube is a commonly used energy-absorbing structure for trains. Its collision characteristics directly affect the impact resistance and collision behavior evolution process of trains. This paper studies the collision dynamics similarity of the small-scale model of a five-hole thin-walled energy-absorbing structure at the end of a high-speed train. Firstly, the dynamic mechanical behavior and governing equations of high-speed train collision were analyzed, and the applicable similarity criterion was derived by similarity transformation to develop a similarity scale model. According to the simulation, the energy absorption, peak force and other key responses of the full-scale prototype collision were analyzed. Then, the applicability of the thickness distortion scale model of the five-hole energy-absorbing structure in the high-speed train was proved by equation analysis and error analysis. The impact dynamic responses of the complete similarity model and the distortion similarity model were discussed. A correction program with collision deceleration as the dependent variable was proposed for the distortion similarity model, and the fitting relationship between the distortion factor and the correction factor was obtained. The results calculated by the proposed method prove that the peak force-deformation-energy absorption error of the thickness distortion similarity model in predicting the dynamic responses of the prototype collision is less than 8%, which means the thickness distortion scale model has good accuracy in the prediction of full-scale prototype collision dynamics responses.

Local public good equilibrium

We extend ratio equilibrium to local public good economies by defining Local Public Good Equilibrium (LPGE). We employ “share functions” for individual agents that allow easy comparisons of consumption utility, both across consumption bundles and across jurisdiction memberships. Share functions furthermore aggregate for parsimonious calculation of equilibrium public good provision within each potential jurisdiction, allowing us to establish a link with hedonic games and deploy results from that literature. We demonstrate in examples how this enables us to show LPGE existence for a far wider class of economies than prior work seeking to extend ratio equilibrium to local public good economies. In particular, we demonstrate LPGE existence with heterogeneous agents, a finite number of agents and jurisdictions, endogenous jurisdictional revenues and expenditures, and robustness against coalitional deviations. LPGE admits wide-ranging jurisdiction structures, and we demonstrate how it can generate results on sorting that have attracted interest in the extant literature.

Study on operation strategy of pumped storage power station under different development models: a case study of China

Abstract Pumped storage, a flexible resource with mature technology, a good economy, and large-scale development, is an important part of the new power system. According to the different stages of the development of the power market, this paper puts forward the corresponding development models of pumped storage power stations, which are successively the “two-part price system” model, the “partial capacity fixed compensation” model, and the “completely independent market participation” model. Then put forward the corresponding business strategies of different development models, establish the economic benefit calculation model, and conduct the simulation. The simulation results show that the internal rate of return corresponding to the above three development models is 6.5%, 7.44%, and 8.23%, respectively. With the continuous improvement of market participation, the economic benefits of pumped storage power stations are also gradually improved, which promotes the cost recovery of pumped storage power stations. In addition, under the three development models, the three factors of capacity electricity price, capacity ratio covered by approved electricity price, and energy conversion efficiency also impact the economic benefits of pumped storage power stations.

Recycling steel slag as fertiliser proxy in agriculture is good circular economy but disrupts plant microbial symbioses in the soil

Modern agriculture depends on synthetic fertilisers to ensure food security but their manufacture and use accounts for ~5 % of the global greenhouse gas emissions. Achieving climate change targets therefore requires alternatives, that while maintaining crop productivity, reduce emissions across the lifecycle of fertiliser utilisation. Steel slag, a nutrient-rich by-product of steel manufacture, offers a viable alternative. Being substantially cheaper than fertilisers, it is economically attractive for farmers, particularly in low-middle income countries of the Global South. However, slag application in agriculture poses risk of pollutant transfer to the human food chain and disruption of key plant-microbe symbioses like the arbuscular mycorrhizal fungi (AMF). Here, using barley as a model crop, we tested the suitability of slag as a fertiliser proxy. Mycorrhizal and non-mycorrhizal barley were grown in soils ameliorated with slag in concentrations of 0, 2, 5 and 10 t ha−1. We analysed slag-mycorrhiza interaction and their combined effects on crop yield and risks to human nourishment. Slag increased grain yield by respective 32 and 21 % in mycorrhizal and non-mycorrhizal barley. Grain concentration of metal pollutants in mycorrhizal and non-mycorrhizal barley fertilised with slag were within the WHO recommended limits. But slag reduced mycorrhizal colonisation in barley roots and extraradical hyphal spread in the soil. The consequent decline in symbiont function lowered AMF-mediated plant nutrient uptake and increased mineral losses in leachates. AMF are keystone species of the soil microbiome. Loss of AMF function presents long-term ecological consequences for agriculture and necessitates a careful evaluation of slag application to soil.

The Impact of Digital Economy and Net Export of Goods and Services Towards Employment in the Selected Southeast Asia Countries

The digital economy is rapidly growing and transforming the way people work and do business globally. This growth has a significant impact on employment in the Association of Southeast Asian Nations (ASEAN) countries. This study aimed to examine the impact of the digital economy and net export on employment in selected ASEAN members, Malaysia, Indonesia, Singapore, and Thailand. Sample years were extracted from 1991 to 2021 and the panel data regression method was applied in this study. The result of this study showed that the digital economy; fixed broadband subscription (LBROAD), internet users (LUSER), and net export (LEXP01) had a significant influence on employment (LTEMP).

Automated Optimization of a Multistep, Multiphase Continuous Flow Process for Pharmaceutical Synthesis.

Flow synthesis is becoming increasingly relevant as a sustainable and safe alternative to traditional batch processes, as reaction conditions that are not usually achievable in batch chemistry can be exploited (for example, higher temperatures and pressures). Telescoped continuous reactions have the potential to reduce waste by decreasing the number of separate unit operations (e.g., crystallization, filtration, washing, and drying), increase safety due to limiting operator interaction with potentially harmful materials that can be reacted in subsequent steps, minimize supply chain disruption, and reduce the need to store large inventories of intermediates as they can be synthesized on demand. Optimization of these flow processes leads to further efficiency when exploring new reactions, as with a higher yield comes higher purity, reduced waste, and a greener synthesis. This project explored a two-step process consisting of a three-phase heterogeneously catalyzed hydrogenation followed by a homogeneous amidation reaction. The steps were optimized individually and as a multistep telescoped process for yield using remote automated control via a Bayesian optimization algorithm and HPLC analysis to assess the performance of a reaction for a given set of experimental conditions. 2-MeTHF was selected as a green solvent throughout the process, and the heterogeneous step provided good atom economy due to the use of pure hydrogen gas as a reagent. This research highlights the benefits of using multistage automated optimization in the development of pharmaceutical syntheses. The combination of telescoping and optimization with automation allows for swift investigation of synthetic processes in a minimum number of experiments, leading to a reduction in the number of experiments performed and a large reduction in process mass intensity values.

The Progress of Reductive Coupling Reaction by Iron Catalysis.

The transition metal catalyzed coupling reaction has revolutionized the strategies for forging the carbon-carbon bonds. In contrast to traditional cross-coupling methods using pre-prepared nucleophilic organometallic reagents, reductive coupling reactions for the C-C bonds formation provide some advantages. Because both coupling partners are reduced in the final products using a stoichiometric amount of a reductant, this approach not only avoids the need to use sensitive organometallic species, but also provides an orthogonal and complementary access to classical coupling reaction. Notably, the reductive coupling reactions feature readily available fragments, promote good step economy, exhibit high functional group tolerance and unique chemoselectivity, which have propelled their increasingly popular in the organic synthesis. In recent years, due to the low price, minimal toxicity, and environmentally benign character, iron-catalyzed carbon-carbon coupling reactions have garnered significant attention from the organic synthetic chemists and pharmacologists, especially the iron-catalyzed reductive coupling. This review aims to provide an insightful overview of recent advances in iron-catalyzed reductive coupling reactions, and to illustrate their possible reaction mechanisms.

Effect of Hydrophilic Function Groups on the Properties of Short‐Chain Fluorocarbon Surfactants

AbstractShort‐chain fluorocarbon surfactants grafted with alcohol, carboxyl and ester functional groups were prepared by quaternization with short‐chain perfluorobutyl sulfonyl fluoride as raw material. The structures of surfactants were characterized by infrared spectroscopy, nuclear magnetic resonance and mass spectrum. The surface activity, micelle formation process and micelle aggregation behavior of surfactants were studied by surface tensiometer, dynamic light scattering particle size analyzer and fluorescent spectrophotometer. The results show that the critical micelle concentration (CMC) of surfactants are 19.3, 7.8 and 2.2 mmol L−1, and the surface tension of the surfactant solution at CMC are as low as 17.3, 19.2 and 18.5 mN m−1, respectively. The standard Gibbs free energy ( ) values of surfactants are negative, and the absolute values of are less than the standard Gibbs adsorption energy ( ), illustrating that the adsorption process is easier than the micelle formation process. In addition, the size distribution of the aggregates is much larger than that of spherical micelles, showing that the surfactant self‐assembled into larger aggregates in solution. The grafted hydrophilic functional groups show a significant effect on the performance of surfactants. The ester‐based surfactant has a lower CMC value, which has the advantages of small dosage, good economy and excellent application value.

Metal-Free Synthesis of Pharmaceutically Relevant Sulfonylureas via Direct Reaction of Sulfonamides with Amides.

A metal-free process has been developed for the sustainable synthesis of medicinally important sulfonylureas in one pot via the direct reaction of sulfonamides with amides in green solvent (DMC). The reaction proceeded efficiently at room temperature, and the products were obtained in good to excellent yields. The use of readily accessible, inexpensive, and environmentally benign starting materials and reagents, metal-free mild reaction conditions, wide substrate scope, tolerance to air and moisture, operational simplicity, and good atom economy are the salient features of this reaction protocol. Gram-scale synthesis of antidiabetic drugs tolbutamide and chlorpropamide in excellent yields further revealed the practical utility of this procedure. Additionally, the synthetic value of this straightforward method is showcased by the late-stage modification of drug molecules, including drug-drug conjugation with good yields. Preliminary mechanistic studies indicated the in situ generation of an isocyanate intermediate, which further reacts with sulfonamide to form sulfonylurea. As compared to other related methods reported for sulfonylurea synthesis, the current method obviates the requirement of traditional multistep protocols involving isolation of hazardous isocyanates and avoids the use of toxic phosgene.

Modular gas-cooled reactor core optimal design and additive manufacturing performance based on SiC matrix dispersed with TRi-structural ISOtropic fuel

High-temperature gas-cooled reactors present significant technical competitiveness in various fields, such as low-carbon electricity, thermal energy, and hydrogen supply. Silicon Carbide (SiC) matrix dispersed with TRi-structural ISOtropic (TRISO) particle fuel is characterized by high-temperature tolerance, radiation resistance, and good neutron economy, which has emerged as a pivotal technological pathway for reactor core design. With the rapid advancement of SiC Additive Manufacturing (AM) technology, there is a substantial increase in core design flexibility, and an innovative gas-cooled reactor design was proposed by Monte Carlo (MC) method in this paper. The Non-uniform Rational B-spline (NURBS), Latin Hypercube Sampling (LHS), second-order polynomial response surface, as well as Genetic Algorithm (GA) were coupled to realize the optimization design for the coolant channel. Besides, a modular fuel design was proposed, and the AM SiC shell was fabricated using Binder Jetting (BJ) technology. Furthermore, the densification of the AM SiC shell and the matrix with SiC powder and SiC microspheres (TRISO simulator) was investigated by Chemical Vapor Infiltration (CVI). Finally, the microscopic morphology analysis and thermal-mechanical performance characterization of the samples were conducted, which demonstrated the technical feasibility and advanced capabilities of the SiC matrix dispersed with TRISO fuel based on AM technology.

Study on sodium-ion anode material - Graphene battery

Batteries are the most common form of energy storage. Sodium-ion batteries are gradually replacing traditional lithium-ion batteries, becoming a key factor restricting their safety, service life, energy density and capacity. With the continuous consumption of energy by human society, the increasing scarcity of mineral resources, and the increasingly severe environmental problems. It is an urgent task to seek new, renewable and clean energy. Sodium-ion battery is expected to be a new type of charge/discharge device because of its high energy conversion efficiency, high energy density, long cycle life, environmental friendliness and good economy. The development of new green and high-efficiency large-capacity energy storage technology is great significance for promoting China’s green and low-carbon energy development. It is great significance for the implementation of China’s “double carbon” strategy. Sodium-ion battery is the most important class of secondary batteries. Sodium-ion battery has high rate, good low temperature resistance, suitable for low salt concentration electrolyte, high safety and other characteristics. The sodium is abundant in the earth, low price, low REDOX potential. That is a class of secondary batteries with great application prospects. With the progress of society and the sustainable development of economy, people’s demand for sodium-ion batteries is also increasing. The “14th Five-Year Plan” New Energy Storage Development Implementation Plan clearly points out that is necessary to carry out the test and demonstration of a new generation of high energy density storage technology represented by sodium-ion batteries.

The Effect of Economic Status and Mother’s Knowledge in Stunting Cases: A Systematic Review

Background: A reduction in the incidence of stunting has been reported globally over the past few decades. However, stunting remains a big problem for developing countries. The purpose of this research was to review in-depth The Role of Social Economy, Knowledge, behaviour, and stunting in Stunting Cases.Narrative studies with scientific journal database sources published in PubMed, Proquest, Science Direct, and Google Scholar were used. The keywords used in the search were Social economy, Knowledge, behaviour, and stunting. The search included research published within the last five years, that is, 2018-2022. A total of 144 articles were found according to the search titles, and 11 articles were selected for review. After the article was obtained, it was tabulated in an Excel table.The findings show that the family economy will support children's nutritional intake and needs so that children are not underweight during this period of growth and development. A good family economy can support childcare patterns, and healthy home settlements so they can access clean water. The family economy plays a role in overcoming the large number of children and preventing early marriages. Parents' knowledge will influence the mother's attitude in caring for and caring for children from birth to adolescence. This knowledge is closely related to the practice of exclusive breastfeeding, traditional food nutrition, the management of food hygiene, the diversity of children's diets, the nutritional value of food including the fulfilment of certain nutrients both micro and macro and education about stunting.Economic status has a very important impact on stunting prevention because it will affect other aspects related to stunting. Not only that, all the research that has been reviewed shows that the educational level of parents will affect attitudes about how to care for their children.

Axial compression behaviour of square concrete-filled stainless-clad bimetallic steel tubular stub columns

Concrete-filled stainless-clad bimetallic steel tube (CFSCBST) members combines the advantages of excellent corrosion-resistance and good economy compared with conventional concrete-filled steel tube (CFST) members, which has great prospects in engineering application. This paper presents a comprehensive experimental and numerical investigation into the axial compression behaviour of CFSCBST stub columns with square sections. A total of eight specimens was conducted on CFSCBST specimens, incorporating varying width-to-thickness ratios, clad ratios and steel strengths, The experimental investigation provided a detailed report on failure modes, load versus displacement and strain response. The experimental results were utilized in a parallel numerical simulation to validate the finite element (FE) model. Subsequently, an extended parametric analysis was conducted to investigate the influence of the strength of the concrete, the substrate steel grade, the clad ratio, and the width-to-thickness ratio were carried out. The data obtained from tests and numerical studies were used to evaluate the applicability of existing design codes AISC/ANSI 360-22, EN 1994–1-1, GB 50936–2014 and DBJ/T 13-51-2020 for predicting the compressive capacity of square CFSCBST stub columns. Overall, a modified design method was proposed, adapted from DBJ/T 13-51-2020, was proposed for CFSCBST stub columns, demonstrating enhanced accuracy in predictions.

PVA/cellulose hydrogel with asymmetric distribution of MoS2 for highly efficient solar-driven interfacial evaporation and electricity generation

Population growth and economic globalization have exacerbated freshwater shortages and energy crises, and solar-driven interfacial evaporation (SDIE) offers a promising solution due to its environmental friendliness, accessibility, and sustainability. However, the highly efficient cogeneration of freshwater and electricity using the SDIE process is a challenge. Herein, a PVA/cellulose hydrogel with asymmetric distribution of MoS2 is proposed as a highly efficient SDIE system to overcome the bottleneck in the cogeneration of freshwater and electricity. By applying material genome engineering and microstructure regulation to improve light harvesting, energy efficiency, evaporation performance, and vapor escape. The evaporation rate of the PVA/cellulose evaporator could reach 3.23 kg m−2 h−1 when desalinating 3.5 wt% seawater under 1 sun and remained basically stable during the long-term continuous evaporation. In addition to desalination, the prepared evaporator also has a potential application in the cyclic utilization of the industrial and domestic wastewater. The synergistic effect of the electron double layer effect and the seawater battery principle produces a high output voltage of 0.714 V. Meanwhile, the optimized solar evaporator demonstrates good mechanical properties, salt resistance, environmental adaptability, and carbon emission economy. This work provides new insights into efficient seawater desalination and power generation, and inspires further research on multifunctional solar-driven interfacial evaporation systems to effectively address water scarcity and energy crises.

Two-layer Optimization-Based Capacity Allocation Method of Integrated Energy Systems

Abstract In this paper, the coupling relationship between energy sources is used to carry out analysis and establish the capacity allocation and optimization model of the integrated energy system. Then a two-layer optimization algorithm is used to establish a linear programming model, which is simulated and analyzed according to the data of a certain region, and solved by CPLEX. The simulation results show that the multi-energy complementary has a good economy and can improve the cleanliness compared with the traditional energy system, which well proves the effectiveness of the proposed capacity optimization model and operation strategy of the integrated energy system.