rss_2.0Ecological Chemistry and Engineering S FeedSciendo RSS Feed for Ecological Chemistry and Engineering Shttps://sciendo.com/journal/ECEShttps://www.sciendo.comEcological Chemistry and Engineering S Feedhttps://sciendo-parsed.s3.eu-central-1.amazonaws.com/64b7ce8764573c28bc2b2d93/cover-image.jpghttps://sciendo.com/journal/ECES140216One-Year-Long, Comprehensive Analysis of PM Number and Mass Size Distributions in Warszawa (Poland)https://sciendo.com/article/10.2478/eces-2023-0047<abstract> <title style='display:none'>Abstract</title> <p>The properties of particulate matter PM, including its impact on the environment and human health, depend mainly on the size (more precisely: size distribution) of the particles since the size is usually dependent on the processes/sources of the PM. This work presents the results of a one-year-long measurement campaign of PM. PALAS Fidas 200 from Airpointer air quality station was used. The PM was measured in Warsaw, Poland continuously from 1st May 2022 to 30th April 2023; size distribution was recorded with 120 s intervals and averaged in 3600 s periods. It was found, that the number and the mass size distribution varied depending on the averaging period (different hours of the day, different days of the week, and different months of the year). Additionally, the authors determined the periods of impact on selected sources (traffic emission, municipal emission, and industrial emission) on the number and mass size distributions of PM at the sampling site. Monitoring of number and mass size distributions of PM is a relatively easy and more cost-effective method than analysing the chemical composition of PM. Therefore, is crucial to develop a method of identifying sources of PM based on size distributions. It was found that such a method can be in the future as successful in source apportionment as in the analysis of chemical compositions.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00472024-01-16T00:00:00.000+00:00Policy of Decarbonisation of the Transport Sector of the Economy of Ukraine: Problems and Perspectiveshttps://sciendo.com/article/10.2478/eces-2023-0046<abstract> <title style='display:none'>Abstract</title> <p>Practically, the strategic guideline for a transformation of transport sector of the Ukraine’s economy is the reduction of the transport carbon footprint. The decarbonisation policy of the Ukrainian transport sector is characterised in the present paper. Moreover, inefficiency of the current policy is proved. The authors created the mathematical model of structural improvement in road transportations by redistribution of transportations volumes between the motor transport and the railway. Guided by the scenario approach, the three most probable scenarios for traffic optimisation are developed, such as pessimistic, basic, and optimistic. The carbon reduction percentage is computed in each of these scenarios. In addition, the priority vectors of the policy of the structural optimisation of the road transport by redistribution of traffic volumes between the motor transport and the railway are determined.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00462024-01-16T00:00:00.000+00:00Perspective Applications of Plasma-Deposited Thin Film Nanocatalysts on Structured Supports: From CO Capture to Wastewater Treatmenthttps://sciendo.com/article/10.2478/eces-2023-0044<abstract> <title style='display:none'>Abstract</title> <p>The urgent need for sustainable solutions to environmental challenges has led to significant research efforts towards innovative processes and technologies capable of addressing global issues such as carbon dioxide (CO<sub>2</sub>) capture and valorisation as well as efficient water-reuse cycles. The majority of processes involved in CO<sub>2</sub> conversion require highly active catalysts for practical implementation. Concurrently, wastewater treatment technologies, critical for achieving sustainable water reuse, often rely on complex multi-stage systems that incorporate advanced oxidation processes (AOPs). Optimising reaction conditions and exploring unconventional approaches to catalytic system design are crucial for enhancing the efficiency of these processes. Among the emerging solutions, the application of thin-film catalysts deposited by cold plasma onto various structured supports has shown promising potential for improving process performance to meet environmental goals. This paper discusses recent advancements in the development of thin-film nanocatalysts based on cost-effective transition metals. It highlights their application in gas-phase reactions, such as CO<sub>2</sub> hydrogenation to value-added products, as well as innovative uses in multiphase gas-liquid systems, including CO<sub>2</sub> capture in aqueous solvents and the ozonation of wastewater.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00442024-01-16T00:00:00.000+00:00Cleaning Methods for Dust Deposited on the Front Cover of Photovoltaic Modulehttps://sciendo.com/article/10.2478/eces-2023-0045<abstract> <title style='display:none'>Abstract</title> <p>Photovoltaic modules are one of the renewable energy sources with great potential for application in various regions of the world as well as for different terrain. They are, however, sensitive to external factors, affecting the overall amount of energy generated, such as solar irradiance, shading effects and any form of soil build-up on the front glass cover of solar device. The latter issue happens over a course of weeks, months and years and the exact pace is determined for a specific location. Nevertheless, dust remaining on the module surface limits the amount of solar irradiation that can reach solar cells. It then leads to a lowered maximum power and correspond to a decrease in energy yield. A way to mitigate soiling effect, outside of natural washing dependent on precipitation, is a regular debris removal. The proposed methods utilise different approaches, namely active cleaning such as manual, mechanical or electrodynamic, or passive cleaning by applying additional hydrophobic or hydrophilic coating to slow down the accumulation tempo.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00452024-01-16T00:00:00.000+00:00How do Different Types of River Maintenance Works Affect the Ichthyofauna of Small European Watercourses?https://sciendo.com/article/10.2478/eces-2023-0051<abstract> <title style='display:none'>Abstract</title> <p>Watercourses serve the needs of agriculture in certain sections and are subject to strong anthropopressure. When agriculture prevails in the catchment, it often has abundant vegetation, macrophytes in particular, and the bottom is covered by a substantial layer of silt. In order to ensure patency of flow and access to water, small watercourses are very often subject to river maintenance works. The aim of the study was to assess the impact of 3 types of works on the diversity of fish species and density of fish in the 1 and 2 year after the works at 21 sites located on 8 rivers in the European Central Plains Ecoregion. As a result of the works, especially in the 1 year after the works, significant changes were found in hydrochemical and hydrological parameters, especially with the increase in velocity and mean depth in watercourses. Additionally, habitat change contributed to differences in the composition of the ichthyofaunal. After 1 year, the diversity of fish species and fish population density increased or remained unchanged after dredging and removal of plants from the river channel, but they decreased after the removal of macrophytes from river banks. After year 2, a decrease in the diversity of fish species and density was observed, associated with re-infestation and siltation of the watercourses. Particularly in the case of dredging and removal of macrophytes from the river bank, maintenance works should not be done too frequently, because some species of natural value disappear.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00512024-01-16T00:00:00.000+00:00The Influence of Selected Transition Elements on Cell Metabolismhttps://sciendo.com/article/10.2478/eces-2023-0043<abstract> <title style='display:none'>Abstract</title> <p>The elements are present in the environment. Moreover, they are used in pharmacy and the production of new materials used in medical applications. They are often as environmental pollutants. They can accumulate in organisms and induce toxic effects on the cellular level. HepG2, L<sub>929</sub> and Caco-2 cell lines were exposed to known concentrations of chromium chloride, iron chloride, nickel chloride, molybdenum trioxide and cobalt chloride (200 or 1000 μ M used alone and in combinations). Concentrations of chromium, iron, nickel, molybdenum and cobalt in the cell lysate and the culture medium were determined by ICP-MS. Moreover, sodium, potassium, calcium and magnesium concentrations were also measured. What is more, cells were observed under light and scanning electron microscope. The dose-dependent increase in the concentration of chromium, iron, nickel, molybdenum and cobalt in all cell lines after incubation with elements was observed. Potassium concentration decreases while sodium calcium and magnesium increase after incubation of cells with of mentioned elements. The incubation of cells with microelements induces cell morphology changes. The presented study shows the crucial role of tested microelements in the induction of cell death as a result of an imbalance of sodium, potassium, calcium and magnesium concentration inside the cell.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00432024-01-16T00:00:00.000+00:00Recycling Strategy of Green Closed-Loop Supply Chain Under Urban and Rural Low-Carbon Planninghttps://sciendo.com/article/10.2478/eces-2023-0050<abstract> <title style='display:none'>Abstract</title> <p>The low-carbon ecological city aims to harmonise sustainable urban development with low-emission planning approaches. Emissions from business production processes are central to low-carbon planning. This paper explores three closed-loop supply chain recycling models - manufacturer, retailer, and third-party -considering carbon trading and emission reduction technology investment. Respective Stackelberg game models are developed incorporating carbon emission reduction costs, recycling costs, carbon trading price, emission intensity, and recycling price. The influence of these variables on carbon emission reduction and profit is examined through numerical analysis. Results indicate the government’s free carbon quota does not impact per-unit carbon reduction or manufacturer profit, nor optimal recycling mode selection. Under specific remanufacturing emission intensity and production cost saving conditions, carbon quota trading can substantially incentivise manufacturers to invest in emission reduction and recycling. With carbon trading and emission reduction technology investment, manufacturer recycling optimises economic and environmental benefits when remanufactured products provide high production cost savings. This fosters sustainable development supporting low-carbon planning.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00502024-01-16T00:00:00.000+00:00Benzo(a)Pyrene in PM10 - Air Monitoring Results in Polandhttps://sciendo.com/article/10.2478/eces-2023-0048<abstract> <title style='display:none'>Abstract</title> <p>Benzo(a)pyrene (B(a)P) is an extremely toxic substance from the group of PAHs (polycyclic aromatic hydrocarbons). These compounds are formed mainly during combustion processes, and they are transported on the surfaces of suspended aerosol in the air. In Poland, both the concentration of suspended dusts and the amount of B(a)P are among the highest in Europe. The aim of the research was to compare levels of B(a)P concentrations in various locations in Poland. Based on multi-year data, coming from the period 2009-2019, linear trends in changes of these levels were determined with the least squares method. The annual courses of B(a)P concentrations in the air show clear seasonal variations. The highest concentrations are observed in the autumn-winter months, the lowest in the spring-summer months. The annual courses of B(a)P/PM10 ratio show clear seasonal variations. This ratio allows to evaluate the content of B(a)P in PM10 particles, expressed in ngB(a)P/μgPM10. The highest ratio values are observed in the autumn-winter months, the lowest ones in the spring-summer months. At most air monitoring stations, the assigned B(a)P concentration trend lines show a weak decline.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00482024-01-16T00:00:00.000+00:00Hydro-Cracked Light Gas Oil Biodesulphurisation by Immobilised Cells on Polyvinyl Alcoholhttps://sciendo.com/article/10.2478/eces-2023-0049<abstract> <title style='display:none'>Abstract</title> <p>Refining petroleum fractions containing heterocyclic sulphur compounds to produce sulphur-free fuels, requires efficient desulphurisation methods. A new biocatalyst has been synthesised by immobilising <italic>Pseudomonas aeruginosa</italic> cells on polyvinyl alcohol by adsorption for hydro-cracked light gas oil bio-desulphurisation. The surface functional groups and biocatalyst morphology have been investigated by Fourier transform infrared spectroscopy and scanning electron microscopy. The bio-desulphurisation of dibenzothiophene as a heterocyclic sulphur model compound of gas oil was achieved with an aqueous-oil ratio (v/v) of 50 %, where the removed mass was 0.3826 mg per gram of biocatalyst at equilibrium condition, bio-desulphurisation rate of 0.375 h<sup>–1</sup> and removal percentage was 95.65 %. The biodegradation of dibenzothiophene and its derivatives in hydro-cracked light gas oil has been determined after a batch process using 0.5 g of the biocatalyst after 5 h of contact time at 37 °C. According to gas chromatography - mass spectrometry, ethyl and trimethyl derivatives of dibenzothiophene have been degraded by higher efficiencies in comparison with other derivatives. Also, thiophenes and mercaptans of the gasoil sample have been degraded simultaneously to some extent. Equilibrium data have been observed to obey the pseudo-first-order kinetic model. The cell immobilisation facilitates the interaction of surface functional groups with sulphur compounds. The synergistic effect of cell immobilisation on the bio-activity of bacterial cells was due to the maintenance of the heterotrophic, bacillus morphology of the cells after immobilisation. This approach provides a simple, economical method with mild operating conditions to produce low-sulphur light gas oil through the biodegradation of heterocyclic sulphur compounds.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00492024-01-16T00:00:00.000+00:00Evaluating the Development Path of Manufacturing Industry Under Carbon Neutralisationhttps://sciendo.com/article/10.2478/eces-2023-0042<abstract> <title style='display:none'>Abstract</title> <p>China’s manufacturing industry faces the dual imperatives of supporting economic growth while reducing emissions to achieve national carbon neutrality targets. This study analyses the potential for decarbonisation across manufacturing sub-sectors. Using factor analysis and fuzzy comprehensive evaluation, it assesses industries based on foundational advantages, growth prospects, and sustainability. The results rank sub-sectors and identify promising areas like eco-friendly equipment and agricultural processing. However, carbon-intensive industries require urgent transformation. To optimise China’s industrial structure for low-carbon development, coordinated efforts across policy, industry, and enterprise are needed. Supportive regulations, industrial integration, and technology adoption can incentivise green manufacturing. By strategically promoting circular economy models, China can enhance quality and efficiency, convert waste into value, and contribute to global climate action. This study provides insights into aligning manufacturing growth with carbon neutrality in the new economic era.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00422024-01-16T00:00:00.000+00:00Eco-Friendly Bioplastic Material Development Sustainable Seaweed Biocompositehttps://sciendo.com/article/10.2478/eces-2023-0036<abstract> <title style='display:none'>Abstract</title> <p>The study focused on the development of an environmentally friendly bioplastic material using sustainable seaweed-based biocomposites. Algal biomass (<italic>Gracilaria edulis</italic>) was processed and combined with starch, glycerol, glacial acetic acid, and chitosan to create flexible, homogenous biopolymer films. These films exhibited comparable physical properties to commercial plastics and retained their inherent colour post-processing. Spectroscopic analysis revealed intense UV-Vis peak points aligned with seaweed composition. Mechanical testing demonstrated adequate strength and flexibility, similar to starch-based bioplastics, with a tensile strength of 3.383 MPa and lower elongation strength of about 31.90 %. Material migration tests indicated a preference for water, suggesting suitability for low-moisture foods. The bioplastic film displayed notable biodegradability and compostability, showcasing its potential as a sustainable alternative for food packaging. This innovative contribution advances eco-friendly bioplastic material, addressing plastic pollution and promoting biocomposite use.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00362023-10-05T00:00:00.000+00:00Sustainable Production of an Iron-Eggshell Nanocomposite and Investigating its Catalytic Potential for Phenol Removalhttps://sciendo.com/article/10.2478/eces-2023-0040<abstract> <title style='display:none'>Abstract</title> <p>The research conducted here will hopefully lead to the creation of a practical, inexpensive method for purging aqueous solutions of contaminating phenolic chemicals. A biosorbent system comprised of eggshells and iron was studied for its potential to effectively detoxify phenol. Both the eggshell and the iron systems were used in the preparation of the adsorbents in order to achieve the desired result of having the properties of both systems. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) were used for characterisation. Batch tests were conducted to evaluate the adsorption capacity of eggshells and iron under the influence of different operating parameters (shaking speed, pH, initial phenol content, and contact time). In the design-expert modelling, the optimisation conditions were found to be a pollutant concentration = 30.0 mg . L<sup>–</sup><sup>1</sup>, pH of 3.00, adsorbent dose = 0.11 mg . L<sup>–</sup><sup>1</sup>, shaking speed = 150 rpm, and time = 120 min for an phenol reduction rate of 94.4 % which it was extremely near to the experimentally value (96.6 %). The CCD modelling that was performed in the RSM verified the findings that were predicted. On the basis of laboratory results, the prediction proved accurate.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00402023-10-05T00:00:00.000+00:00Anthropogenic Impact on the Quality of Water and Agricultural Soil in Guadiana Valley, Durango, Mexicohttps://sciendo.com/article/10.2478/eces-2023-0039<abstract> <title style='display:none'>Abstract</title> <p>One of the most important effluents in Guadiana Valley, Durango is El Tunal River, mostly used for agricultural and livestock supply. This river has been polluted by agricultural activity and wastewater discharges. Thus, this study aimed to evaluate the current quality of water and agricultural soil near the river, to estimate the environmental situation of the agricultural sector and its main pollution sources. Hence, a total of 24 soil and five water samples were taken, analysing parameters of organic matter, pH, nutrients, and heavy metals(loid)s (As, Cd, Pb, Zn) in five agricultural areas. The randomised experimental design showed significant variations in soil (<italic>p</italic> &lt; 0.05) of organic matter, nitrogen, As, and Pb between sampling points, confirming suitable conditions for agriculture. Although contamination by heavy metal(loid)s exists, it is below permitted levels. In contrast, the physicochemical quality of the water indicated high levels of phosphates, total dissolved solids, and total coliforms, mainly in the nearest site of a wastewater treatment plant, thus the quality of the water is not suitable for consumption and irrigation for sensitive crops. Nevertheless, rainfall contributes to improve the quality of the river by diluting pollutants. Moreover, constant use of this water might represent a risk to human health and agriculture as it could transport elements to crops or soil, becoming a severe environmental problem.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00392023-10-05T00:00:00.000+00:00Hydrochemical and Ecotoxicological Characterisation of Water Samples from Moldova Noua Area, Romaniahttps://sciendo.com/article/10.2478/eces-2023-0038<abstract> <title style='display:none'>Abstract</title> <p>The abandoned copper mine in the Moldova Noua area is still producing mining pollution today due to the drying of tailings ponds and the carrying of contaminated dust by the winds, leading to potential contamination of surface waters and groundwaters. The purpose of this study is the assessment of some surface waters and groundwaters potentially contaminated by mining pollutants from Moldova Noua area regarding their hydrochemical and ecotoxicological properties. The physicochemical parameters (pH, conductivity, dissolved oxygen, and turbidity) were determined <italic>in situ</italic>, with the concentrations of heavy metals (As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) being determined in the laboratory. Inhibition of acid phosphatase enzymatic activity and yeast toxicity tests were the two ecotoxicological tests used for the evaluation of mining pollution effects on the quality of surface waters and groundwater. The results highlighted that most of the physicochemical parameters and heavy metal concentrations were within normal limits. With the exception of the surface water sample collected from the Bosneag River, upstream of Moldova Noua, all samples induced inhibition compared to the positive control in the ecotoxicological tests applied. Statistically significant correlations were observed, with the total concentration of iron ions presenting the most statistically significant correlations with other parameters. A grading scale was used to assess the state of the waters, highlighting the weak impact of mining pollutants on the analysed samples.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00382023-10-05T00:00:00.000+00:00Physiological Perspective of Starch as a Carbon Source in Two Varieties of Koch in Northern Mexicohttps://sciendo.com/article/10.2478/eces-2023-0033<abstract> <title style='display:none'>Abstract</title> <p>The study took as a purpose to determine the Total Carbon (TC) content in the biomass, the Starch Carbon fraction (SC) and its annual dynamics in the biomass of perennial organs (stem and root) in adult trees of two of walnut tree (<italic>Carya illinoinensis</italic>). Four adult Western and Wichita tree stem and root samples were carried out monthly for a whole year. The TC was determined with an elemental analyser and the SC has gotten based on the molecular mass of the glucose (0.40 gC/gGlucose). <italic>t</italic>-Student test was performed between varieties per organ for the comparison of TC and SC through the program SPSS 15.0 with a significance of <italic>p</italic> ≤ 0.05. The results in Western variety were 160.02 kg TC and 4.90 kg SC to 7.54 kg SC in the stem; 64.58 kg TC and 1.74 kg SC to 3.09 kg SC in the root; in Wichita variety were presented 119.72 kg TC and 4.49 kg SC to 6.83 kg SC in the stem; 45.72 kg TC and 1.35 kg SC to 2.75 kg SC in the root. The root was the organ where the greatest amount of SC was stored in relation to the stem, due this latter constitutes a transport organ. Temperature has a marked inversely proportional influence on the accumulation of SC in both varieties. Global solar radiation and solar radiation proportionally influence the accumulation of SC.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00332023-10-05T00:00:00.000+00:00Mapping of Inland Excess Water Using Geographical Information System and High-Resolution Satellite Images: A Case Study of SREM, Serbiahttps://sciendo.com/article/10.2478/eces-2023-0037<abstract> <title style='display:none'>Abstract</title> <p>Extreme hydrological events, such as floods and droughts, are becoming more frequent as a result of climate change, leading to negative impacts on various economic sectors. The Pannonian-Carpathian Basin is particularly affected by the increasing frequency of hazardous hydrological events. Agricultural production, which is a highly significant economic sector in the region, is particularly vulnerable to these unfavourable climatic conditions. Changes in precipitation patterns and soil moisture levels can lead to reduced crop yields, while floods can pollute water sources and erode fertile soil. Mapping of Inland Excess Water (IEW), also known as ponding water or waterlogged areas, is crucial for informed decision-making, damage compensation, risk management, and future prevention planning. Remote sensing technology and machine learning have been demonstrated to be valuable tools for the mapping of IEW. The 2014 floods in Southeastern and Central Europe serve as a reminder of the importance of effective flood risk management. This study used a Geographical Information System (GIS) and a Semi-automated Classification Processing (SCP) tool to process high-resolution RapidEye satellite images from the 2014 floods in the Srem region of Serbia. The Spectral Angle Mapping (SAM) classification model was used to produce a map of IEW. The SAM model achieved an overall accuracy of 92.68 %. The study found that IEW affected approximately 2.90 % or 99.59 km² of the territory in Srem. The obtained maps can be used by responsible water management agencies to prevent and control excessive inland water.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00372023-10-05T00:00:00.000+00:00Effect of Mn(II) on Tetracycline Degradation by a Selected Strain sp.https://sciendo.com/article/10.2478/eces-2023-0041<abstract> <title style='display:none'>Abstract</title> <p>Removal of residual tetracycline (TC) in the environment is an important issue for pollution control. In this study, a TC-degrading strain named JX_1 was isolated from the soil around an industrial park, the strain was identified as <italic>Burkholderia</italic> sp. by 16s rDNA sequencing analysis. The effects of various factors on TC degradation by the strain were studied, results indicated that the inoculation amounts and liquid volume had little effect on TC degradation rate. However, the degradation rate of TC by strain increased with the increase of pH, and the residual concentration increased gradually with the initial TC concentration increased. The degradation rate of 125 mg/L TC by strain JX_1 was 75.76 % under the conditions of temperature 37 °C, 2 mL inoculation amount and 200 mL liquid volume. Under the same conditions, the degradation rate of TC was increased to 91.39 % with the addition of 0.75 g/L MnSO<sub>4</sub>, indicating that Mn(II) could improve the degradation rate of TC by strain JX_1 to a certain extent.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00412023-10-05T00:00:00.000+00:00Corporate Environmental Management with Digital Transformation: Theory and Applicationshttps://sciendo.com/article/10.2478/eces-2023-0014ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00142023-07-08T00:00:00.000+00:00Environmental Regulation, Environmental Policy Complexity and Technological Innovation Efficiencyhttps://sciendo.com/article/10.2478/eces-2023-0015<abstract> <title style='display:none'>Abstract</title> <p>Previous studies on the relationship between environmental regulation (ER) and technological innovation efficiency of defence industry (TIE-DI) mainly focus on variability and complexity, while few empirical studies have incorporated environmental flexibility into models, and most of them are based on questionnaires. Therefore, this paper takes environmental regulation and environmental policy complexity (EPC) as the entry point, so as to discuss the feasibility of improving the technological innovation efficiency of China’s defence industry enterprises (CDI), which aims to empirically test the mechanism of ER and EPC on improving the efficiency of applied technological innovation of China’s defence industry enterprises. The research conclusion provides sufficient theoretical basis and empirical support for strengthening the technical innovation efficiency support, standardising the market order and the market leading, establishing the information disclosure mechanism and improving the internal control of industrial enterprises.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00152023-07-08T00:00:00.000+00:00Carbon Emission Reduction Effect of Digital Infrastructure: From the “Broadband China” Strategyhttps://sciendo.com/article/10.2478/eces-2023-0030<abstract> <title style='display:none'>Abstract</title> <p>The establishment of digital infrastructure embodies a pivotal instrument in propelling developmental metamorphosis, whilst fostering energy preservation and emission abatement. By employing municipal-level data spanning the period from 2009 to 2019, this research establishes a quasi-natural experiment anchored upon the “Broadband China” strategy. Employing the Difference-in-Differences (DID) methodology, this inquiry thoroughly examines the influence of digital infrastructure construction on the alleviation of carbon emissions. The findings indicate that the implementation of digital infrastructure exerts a notable impact on the reduction of carbon emissions. Moreover, carbon emission reduction resulting from digital infrastructure construction exhibits distinctive characteristics of heterogeneity. The empirical evidence presented within this study serves as a fundamental cornerstone for attaining the objectives of carbon peaking and carbon neutrality.</p> </abstract>ARTICLEtruehttps://sciendo.com/article/10.2478/eces-2023-00302023-07-08T00:00:00.000+00:00en-us-1