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This article reveals the source of exporters' better environmental performance (exporters' environmental premium) for Chinese firms with a model based on heterogeneous firm theory and empirical analysis with a difference‐in‐differences method based on the Chinese export tax refund reduction in 2004 and comprehensive firm‐level environmental survey data. The results show that exporting releases Chinese firms' financing constraints and enables them to upgrade production technologies quickly by applying advanced production technology (capital‐embodied technological upgrading) rather than by upgrading abatement technologies, to drive down sulfur dioxide (SO2) intensity and energy intensity. Exporting also reduces a firm's average energy intensity and SO2 intensity by reallocating resources from energy‐intensive and polluting production and firms to cleaner ones, that is, the resource reallocation effect. However, Chinese firms cannot expand their production much when trade costs decrease, which makes it difficult for the scale effect to work well. [ABSTRACT FROM AUTHOR]

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This study explored the feasibility of utilizing varying proportions of metakaolin – MK (4, 6, or 8 wt%) and two types of alkaline liquid reagents – LR (incorporating nanosilica and NaOH or KOH) to induce in situ geopolymer formation in high-alumina refractory castables. The impact of geopolymeric binders on processing behavior, as well as on the physico-mechanical and structural properties of the designed refractories, was investigated within a temperature range of 40–1250 °C. Optimal physico-mechanical performance and thermal shock resistance were achieved with compositions 8 MK-Na (prepared with 8 wt% MK and NaOH-based LR) and 6 MK-K (containing 6 wt% MK and KOH-based LR). The liquid generation during viscous sintering enhanced castable densification at 1100–1250 °C and promoted the formation of nepheline, kalsilite or leucite phases. This resulted in microstructures featuring a suitable interfacial bond strength between the glassy phase and alumina grains, leading to an interlocking structure and improved castable properties. These achievements underscore the potential of geopolymer-bonded high-alumina castables for applications involving intermediate temperatures (800–1200 °C), such as those found in the petrochemical and non-ferrous metal industries. [ABSTRACT FROM AUTHOR]

The UK House of Commons Foreign Affairs Committee has released a report on the security of UK access to critical minerals, expressing concerns about supply disruptions and dependence on autocratic nations. The report highlights that there have been over 200 policies and regulations implemented worldwide regarding critical minerals. China currently dominates the production and processing of these minerals, raising concerns about its control over the global technology sector. The UK is actively searching for its own reserves of critical minerals and is considering reopening old mines to secure supplies. The UK has a history of mining critical minerals such as tin and tungsten, as well as non-critical minerals like copper, gold, and zinc. The UK is believed to have reserves of all critical minerals except for niobium. The UK Critical Minerals Intelligence Centre has utilized geological mapping, mining history, and soil chemistry to identify potential reserves of critical minerals within the country. The demand for critical minerals is expected to significantly increase by 2030 due to the rising need for rechargeable batteries and low-emission power generation technology. [Extracted from the article]

Objective: Understanding the spatial connectivity of elasmobranch populations is critical for regional fisheries management. The Blacktip Shark Carcharhinus limbatus is abundant in coastal waters of the Gulf of Mexico (GoM) and important in recreational and commercial fisheries. Based on genetic and tagging studies, GoM Blacktip Sharks are currently managed under separate quotas between the eastern and western GoM (divided at 88°W), but no studies have used vertebral chemistry to assess the population structure of adult Blacktip Sharks. Methods: We compared vertebral elemental signatures (barium [Ba], magnesium [Mg], manganese [Mn], strontium [Sr], and zinc [Zn]) for the first year of life with last occupied habitats (vertebral edges) in Blacktip Sharks collected from the western (Texas and Louisiana) and eastern (Alabama and Florida) coastal waters of the northern GoM. Result: We found significant regional differences in Ba, Mg, Mn, and Sr vertebral edge signatures, suggesting ecological separation of Blacktip Sharks. Significant correlation between first‐year and edge signatures suggested a high degree of residency between life stages. Cross‐validated discriminant function analyses yielded highest regional classification accuracies when Florida sharks were grouped separately west of 88°W (90%), demonstrating the unique elemental signatures of eastern versus western GoM Blacktip Sharks under current management delineations. Conclusion: Combined, these findings demonstrate that trace element markers can distinguish regional populations of Blacktip Sharks and provide a complimentary approach in addition to genetics and physical tagging to support current stock management efforts. Impact statementStocks of Blacktip Sharks are managed under separate quotas in the eastern and western Gulf of Mexico. In this study, elemental signatures in mineralized vertebral cartilage of Blacktip Sharks confirm ecological population separation. Natural chemical tags in shark vertebrae offer an additional tool to characterize population connectivity and stock delineation for highly migratory shark species. [ABSTRACT FROM AUTHOR]

• Long-term analysis on the rainwater chemistry during 2011–2020. • Despite the improvement, the situation of acid rain frequency and precipitation pH in Zhuzhou City are still serious comparied to other cities in China. • The changs of nss-SO 4 2−/NO 3 − ratio reveals the acid type in Zhuzhou is gradually changing from sulfuric acid type to the compound type of both sulfuric acid and nitric acid. • Analysis on the rainwater chemistry shows The Zhuzhou municipal government should be cautious in implementing ammonia emission control measures. Zhuzhou was one of the most polluted cities in China with the serious acid rain. Due to the implementation of air pollution control measures from 2016 to 2018, the acid rain pollution in this city has reduced. In order to understand the recent situation, a comprehensive study on the acid rain was carried out from January 2011 to December 2020. The pH values during the study period varied from 3.3 to 7.5, with a volume-weighted mean value of 4.7. The predominant acidic components of the precipitation were SO 4 2− and NO 3 −, accounting for 89.3% of the total anions. The ratio of non-sea-salt SO 4 2− to NO 3 − showed a decreasing trend, revealing that the pollution type of acid rain changed from sulfuric acid type to sulfuric acid and nitric acid compound type. The correlation analysis (p < 0.05) showed that SO 4 2− was positively correlated with NH 4 +, Ca2+, and Mg2+; hence, it predominated in precipitation as (NH 4) 2 SO 4 , NH 4 HSO 4 , CaSO 4 , and MgSO 4. Significant positive correlation of Ca2+ with Mg2+ shows that they may originated mainly from crust. Significant positive correlation between SO 4 2− and F− and Cl− indicate that their source may be related to the non-ferrous metal smelting industry in Zhuzhou. Further correlation analysis shows that emissions from the non-ferrous metal smelting industry in the area have a large significant on SO 4 2− and F− in precipitation, while Cl− may still be emitted from other anthropogenic sources. [Display omitted] [ABSTRACT FROM AUTHOR]

The huge carbon stock in humus layers of the boreal forest plays a critical role in the global carbon cycle. However, there remains uncertainty about the factors that regulate below-ground carbon sequestration in this region. Notably, based on evidence from two independent but complementary methods, we identified that exchangeable manganese is a critical factor regulating carbon accumulation in boreal forests across both regional scales and the entire boreal latitudinal range. Moreover, in a novel fertilization experiment, manganese addition reduced soil carbon stocks, but only after 4 y of additions. Our results highlight an underappreciated mechanism influencing the humus carbon pool of boreal forests. [ABSTRACT FROM AUTHOR]

Zinc-air batteries and zinc-air fuel cells (ZAFC) are types of metal-air batteries that use zinc and oxygen from the air to generate power. They have high energy densities and are cost-effective to manufacture. During discharge, zinc particles form a porous anode saturated with electrolyte, while oxygen reacts at the cathode to form hydroxyl ions that migrate into the zinc paste and release electrons to travel to the cathode. In this study, a ZAFC was designed and produced with polyvinyl chloride (PVC) thermoplastic without any separator. The performance of the prepared air cathode in various temperatures and concentrations of the KOH electrolyte was evaluated. The results showed high current density and low Tafel slope at a high and low current density at a temperature of 318 K and a concentration of 4M. The prepared ZAFC has an open-circuit potential (OCP) of 1.346 V. The current density of 166.5 mA · cm² was obtained at the onset potential of 0.73 V. The power density and discharge capacity of the cell were 205.5 mW, and 283 mAh, respectively. These results show a high-performance single cell. [ABSTRACT FROM AUTHOR]

Oxidation self-charging batteries have emerged with the demand for powering electronic devices around the clock. The low efficiency of self-charging has been the key challenge at present. Here, a more efficient autoxidation self-charging mechanism is realized by introducing hemoglobin (Hb) as a positive electrode additive in the polyaniline (PANI)-zinc battery system. The heme acts as a catalyst that reduces the energy barrier of the autoxidation reaction by regulating the charge and spin state of O2. To realize self-charging, the adsorbed O2 molecules capture electrons of the reduced (discharged state) PANI, leading to the desorption of zinc ions and the oxidation of PANI to complete self-charging. The battery can discharge for 12 min (0.5 C) after 50 self-charging/discharge cycles, while there is nearly no discharge capacity in the absence of Hb. This biology-inspired electronic regulation strategy may inspire new ideas to boost the performance of self-charging batteries. [ABSTRACT FROM AUTHOR]

Introduction: According to Barros (2017), Bentonite is a mixture of clays, generally impure, very fine grained, formed mainly by 60 to 80% of montmorillonite and also Kaolinite, Calcite and Pyrite. At the operational base of Petromoc Maputo Company, there is a set of tanks for fuel storage, that from a complex of tanks with coupled pipelines for the entry and withdrawal of fuels and effluent disposal. Objective: To evaluate the use of bentonite in the removal of toxic cations from the effluents generated at Petromoc Company. Materials and Methods: Bentonite samples were collected at the Industrial Minerals company. The effluent and influent samples were collected in the separator box of the operational base. The physicochemical experiments were carried out at the Analytical Chemistry Laboratory of the Eduardo Mondlane University. For the physical characterization of the bentonite, the pycnometric density, porosity (P) and specific surface area were determined. The mineralogical characterization was performed by X-ray diffraction analysis. The chemical characterization of the effluent and influent was performed by Inductively Coupled Plasma Atomic Emission Spectroscopy. Results and Discussion: Mineralogical characterization showed the presence of bentonite minerals. The pH of the effluent before interacting with the bentonite was 3.22, after interaction the pH is between 5.8 and 9. High concentrations of Cadmium (Cd), Chromium (Cr), Copper (Cu), Titanium (Ti) and Zinc (Zn) were determined in the effluent before the interaction with the bentonite. After the interaction, a removal of toxic elements is verified. Conclusions: The bentonite showed high efficiency in the removal of toxic cations. [ABSTRACT FROM AUTHOR]

Although Moringa is an important vegetable crop elsewhere, its nutritional and non-food uses are not widely known in Botswana community. This study was conducted to determine the chemical composition and mineral contents of leaves of Moringa oleifera trees grown in Gaborone, Botswana. The leaf samples were collected from Moringa trees grown in the backyards of six different households in Gaborone city. They were dried separately at 55 ºC for 24 h and then ground to obtain a powder for analysis. The data on the proximate composition of the Moringa samples were subjected to Analysis of Variance to determine statistical differences among the mean values. The overall mean values of moisture, fat, protein, ash, fiber and total available carbohydrates of the leaves were 6.93 ± 0.16, 7.78 ± 0.13, 27.1 ± 0.43, 7.34 ± 0.31, 9.1 ± 1 and 46.5 ± 3%, respectively. The Moringa leaves contained average values of 520 ± 96.0, 7.7 ± 1.3, 30.1 ± 15.5, 0.8 ± 0.1, 82.6 ± 6.4, 1.7 ± 0.2, 1.6 ± 0.2 and 0.02 ± 0.00 mg/100g of Calcium, Iron, Sodium, Zinc, Magnesium, Aluminum, Manganese and Chromium, respectively. Significant differences were observed for moisture, fat, protein and ash contents among the six Moringa samples. The results showed that the leaves are rich in nutrients, particularly with high amounts of protein and ash. This suggests that Moringa leaf could serve as an important protein and mineral supplement in the diet and can be consumed as a vegetable in Botswana. The difference in composition observed between the Moringa leaf samples suggests a possible genotypic difference between the Moringa trees used in this experiment. Thus, there is a need for further study to verify this. [ABSTRACT FROM AUTHOR]

Zinc-nitrate batteries can integrate energy supply, ammonia electrosynthesis, and sewage disposal into one electrochemical device. However, current zinc-nitrate batteries still severely suffer from the limited energy density and poor rechargeability. Here, we report the synthesis of tetraphenylporphyrin (tpp)-modified heterophase (amorphous/crystalline) rhodium-copper alloy metallenes (RhCu M-tpp). Using RhCu M-tpp as a bifunctional catalyst for nitrate reduction reaction (NO3RR) and ethanol oxidation reaction in neutral solution, a highly rechargeable and low-overpotential zinc-nitrate/ethanol battery is successfully constructed, which exhibits outstanding energy density of 117364.6 Wh kg-1 cat, superior rate capability, excellent cycling stability of ~400 cycles, and potential ammonium acetate production. Ex/in situ experimental studies and theoretical calculations reveal that there is a molecule-metal relay catalysis in NO3RR over RhCu M-tpp that significantly facilitates the ammonia selectivity and reaction kinetics via a low energy barrier pathway. This work provides an effective design strategy of multifunctional metal-based catalysts toward the high-performance zinc-based hybrid energy systems. [ABSTRACT FROM AUTHOR]

In this study, we capture the impact of changing temperature and rainfall patterns on the estimated consumption of macro-and micronutrients among households in Malawi. We apply a fixed-effects model to household panel data collected between 2010 and 2017, which contains detailed information on food consumption, combined with rainfall and temperature data over the past 30 years. In turn, we aim to identify the impact of weather shocks on household food and nutrition security. We find decreases in rainfall from the long-term average results in declining daily consumption of macronutrients (carbohydrates, protein, fat), and micronutrients (iron, zinc, vitamin C, and B2). Increases in temperature from the long-term average are associated with reduced daily consumption of carbohydrates, protein, iron, zinc, vitamin A, B2, folate, and B12. These results suggest that reduced rainfall and higher temperatures will exacerbate food insecurity in Malawi. As the effects of climate change are becoming more apparent, enhancing our understanding of the effect of weather shocks on nutrition in developing countries will be vital to aid policymakers to implement targeted interventions to advance food and nutrition security in Sub-Saharan Africa. This will be essential to achieve the sustainable development goal of 'Zero Hunger' by 2030. [ABSTRACT FROM AUTHOR]

Emissions from the non-ferrous metal industry are a major source of carbon emissions in China. Understanding the decoupling of carbon emissions from the non-ferrous metal industry and its influencing factors is crucial for China to achieve its "double carbon" goal. Here, we applied the Tapio decoupling model to measure the decoupling status and developmental trends of carbon output and emissions of the non-ferrous metal industry in China. The panel interaction fixed effects model is used to empirically analyze the influencing factors of carbon emissions in China's non-ferrous metal industry. The results show that carbon emissions from China's non-ferrous metal industry have experienced three main states: strong decoupling, growth connection, and negative growth decoupling. The carbon emissions of the non-ferrous metal industry in some eastern and central provinces from 2000 to 2004 were in a negative decoupling state. Most provinces in the western and central regions were either in a strong or weak decoupling state based on the developmental trend of the decoupling state of carbon emissions. However, from 2015 to 2019, the decoupling status of carbon emissions in most provinces in western and central China had a significantly negative, weakly negative, or a negative growth decoupling status. Energy structure, energy intensity, cost, and non-ferrous metal production all have a positive driving effect on carbon emissions in the non-ferrous metal industry. Production had a mitigating effect on carbon emissions in the non-ferrous metal industry between 2010-2014 in the eastern region of China. From the results of our study, we propose policy recommendations to promote a strong decoupling of carbon emissions from the non-ferrous metal industry by improving energy structure, reducing energy intensity, and optimizing production capacity. [ABSTRACT FROM AUTHOR]

The article focuses on the potential of hyperaccumulators to be used for phytomining, a process of using plants to extract metals from contaminated soils, including hyperaccumulators, phytomining, and environmental benefits.

Since the European Commission proposed in July 2021 to implement a Carbon Border Adjustment Mechanism (CBAM), the impact mechanism has received increasing attention worldwide. This study aims to analyze the impact of carbon border tariffs on China's carbon-intensive industries and simulate the risk transmission within China's industrial complex network based on the complex network modeling and cascading failure analysis. The results showed that the industries subject to carbon border tariffs played an essential role in China's entire industrial structure, which is closely related to industries including construction, metal, and manufacturing. If the carbon border tariffs are imposed on the steel industry, China's relevant industries will be reduced by 1.29%, followed by the fertilizer industry and non-ferrous metal industry with proportions of 1.11% and 0.95%, respectively. When the industrial transmission threshold reaches 0.8, the export shocks will affect the entire industrial network, leading to a rapid growth in the number of infected industries. By depicting the industrial linkage and impact mechanism of carbon border tariffs, this study is expected to provide practical suggestions and implications for carbon-intensive industries towards sustainable low-carbon transition under carbon border tariffs. [ABSTRACT FROM AUTHOR]

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of manganese(II)‐betaine complex as a nutritional feed additive for all animal species and categories. Based on the tolerance study performed in chickens, the FEEDAP Panel concluded that the additive is safe for chickens for fattening when used up to the maximum proposed level of manganese in feed; this conclusion was extrapolated to all animal species and categories at the corresponding maximum manganese levels in complete feed (100 mg Mn/kg feed for fish and 150 mg Mn/kg feed for all other animal species). The FEEDAP Panel concluded that the use of additive in animal nutrition does not represent a concern for consumer safety or for the environment. The additive is irritant to the eyes, but not irritant to skin. Owing to the presence of nickel the additive is considered to be a dermal and respiratory sensitiser. The Panel concluded that the additive is efficacious as a nutritional additive for all animal species under the proposed conditions of use. [ABSTRACT FROM AUTHOR]

The oil and gas industry's inherent volatility, influenced by geopolitical events, supply and demand fluctuations, and economic conditions, poses significant challenges to project schedules and budgets. Accurate project cost prediction is vital for effective project management, particularly in long-term projects in PERTAMINA's downstream sector. Currently, PERTAMINA faces project delays, primarily due to market volatility and lengthy preparatory activities. This time gap results in budget disparities, necessitating an accurate cost escalation method. In current PERTAMINA Downstream project budgeting, cost escalation methods adjust the Owner's Estimate during tender processes but typically only focus on the bidding year, omitting the construction period gap which should also be factored in. This paper analyzes various benchmarks, including gold price, Big Mac index, US Dollar index, and Indonesia's inflation rate, considered as alternative currencies for precise project budgeting, and selects the most suitable one. Results indicate that the Gold Price emerges as the best benchmark for precise cost escalation due to its consistent growth trend, in line with the RAND Study's insights on the impact of omitting scope and risks. [ABSTRACT FROM AUTHOR]

The coarse arsenic fume is an inevitable product of the gold roasting and smelting process in the treatment of complex arsenic-containing gold concentrate. The way it is effectively disposed of safely, environmentally friendly, and recovered as resources, has become a technical problem for the gold and non-ferrous metal smelting industry. In the production process of a gold smelting company, the mass fractions of arsenic trioxide, gold, and silver in the coarse arsenic fume are 86. 50 %,1. 1 g/t, and 11 g/t, respectively. The coarse arsenic fume is treated using closed fluidization transportation of coarse arsenic fume, multi-stage gradient temperature-controlled distillation, multi-stage slow-cooling crystallization of arsenic, leaching of gold and silver from arsenic-removal slag and recycling of arsenic-removal tail gas. This technology has been successfully applied on an industrial scale. The primary product obtained has an arsenic trioxide mass fraction of 99. 51 %,and the arsenic recovery rate reaches 99. 10 %. The gold and silver recovery rates are 81. 17 % and 79. 94 % respectively. The industrial application of the purification and production of arsenic trioxide from coarse arsenic fume successfully transforms coarse arsenic fume hazardous waste into a secondary high-value resource, overcoming the technical bottlenecks of producing high-purity arsenic trioxide from coarse arsenic fume both domestically and internationally. The comprehensive recovery, recycling, and clean production of coarse arsenic fume resources have significant environmental, economic, and social benefits, demonstrating wide-ranging value for promotion and application. [ABSTRACT FROM AUTHOR]

By-products from the non-ferrous industry are an environmental problem; however, their economic value is high if utilized elsewhere. For example, by-products that contain alkaline compounds can potentially sequestrate CO2 through the mineral carbonation process. This review discusses the potential of these by-products for CO2 reduction through mineral carbonation. The main by-products that are discussed are red mud from the alumina/aluminum industry and metallurgical slag from the copper, zinc, lead, and ferronickel industries. This review summarizes the CO2 equivalent emissions generated by non-ferrous industries and various data about by-products from non-ferrous industries, such as their production quantities, mineralogy, and chemical composition. In terms of production quantities, by-products of non-ferrous industries are often more abundant than the main products (metals). In terms of mineralogy, by-products from the non-ferrous industry are silicate minerals. Nevertheless, non-ferrous industrial by-products have a relatively high content of alkaline compounds, which makes them potential feedstock for mineral carbonation. Theoretically, considering their maximum sequestration capacities (based on their oxide compositions and estimated masses), these by-products could be used in mineral carbonation to reduce CO2 emissions. In addition, this review attempts to identify the difficulties encountered during the use of by-products from non-ferrous industries for mineral carbonation. This review estimated that the total CO2 emissions from the non-ferrous industries could be reduced by up to 9–25%. This study will serve as an important reference, guiding future studies related to the mineral carbonation of by-products from non-ferrous industries. [ABSTRACT FROM AUTHOR]

Critical nonferrous metals are of strategic importance to the development of today's manufacturing industry, especially under sustainable circumstances. To explore the trade patterns of the critical nonferrous metal resource industry chain and analyze its competitive advantages at different stages, this paper takes cobalt as an example, constructs the directional weighted network of the trade of typical products at each stage of the global cobalt industry chain from 2002 to 2020 based on the trade data of cobalt, cobalt oxide, electrolytic cobalt and cobalt acid lithium, uses trade and market concentration index to analyze the evolution pattern of overall global cobalt products trade, analyzes the cobalt competitive situation of China among typical trading parties. The results show: (1) Developed countries or regions attach more importance to the downstream of the cobalt industry chain. (2) The overall trade volume of cobalt has been gradually increasing, cobalt oxide and lithium cobalt oxide still occupied the majority share of trade among countries. (3) China is more dependent on cobalt ore and cobalt oxide from the Democratic Republic of Congo, and may face a shortage of cobalt and cobalt oxide; the competitiveness of China's cobalt industry is second only to the United States. (4) The United States, Germany, and other countries pay more attention to the ability of betweenness centrality and the distribution of export structure. Accordingly, it is proposed to pay attention to the diversification of the supply side, build a global cobalt product trade risk assessment system, accelerate the up-stream and downstream extension of the industry chain and take the lead in relieving the investment pressure of enterprises, to adapt to the internal and external environment evolution, to enhance the control of the critical nonferrous metals industry chain, both in the international and domestic market. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) is a disruptive technology which continues to challenge conventional manufacturing methods. New generations of materials for metal AM are sought to enable components with new functionalities and to save costs. However, many within the AM industry are primarily focused on metal alloys such as titanium alloys, cobalt alloys, nickel superalloys, aluminum alloys or stainless steels. This article presents a detailed overview of emerging non‐ferrous metals in the AM industry and their recent development. The potential and challenges of these materials and their adoption by AM are highlighted and compared to those of conventional materials. Furthermore, qualification pathways and supply issues for newly developed materials are discussed. This perspective is based on literature review and a thorough analysis of the metal AM industry. [ABSTRACT FROM AUTHOR]

There is a combined pollution of heavy metals and residual organic agents for mineral dressing and smelting in nonferrous metal industry area. The transport behaviors of butyl xanthate (BX) in quartz sand， Fe-coated sand and Fe/Cu-coated sand were investigated using saturated sand column experiments and mathematic model. The results show that quartz sand loading Fe (0.07mg/g) on the surface can reduce the recovery rate of BX from 89.8% to 45.3%， and it decreases by 41.5% with the doubling of iron content. When CuO was loaded subsequently on the Fe-coated sand，BX could react with Cu2+ to generate CuBX. And the transport of BX was completely inhibited when Cu was loaded within a range of 0.010~0.055mg/g. [ABSTRACT FROM AUTHOR]

Effective dehydration and flocculation of mine slurries or sludge is important for nonferrous metal industries and environmental engineering. However, the mechanisms for the flocculation of slurry remain largely unclear. This paper presents the results of a series of flocculation tests, which was conducted on the slurry suspensions treated by xanthan gum (flocculant) at different pH values. It is shown that the settlement rate of mine slurry particles can be accelerated by adding xanthan gum, and the maximum sedimentation rate was obtained at a pH value of 5.9, and the final volume of flocs is significantly increased due to the addition of the flocculant. In addition, the settlement rates of xanthan gum-treated slurry suspensions at the pH values of 3, 5 and 7 decrease slightly compared with the reference slurry suspensions with pH=5.9, and the slurries remained stable as suspensions at the pH value of 9 and 11. The zeta potential measurement and SEM image analysis show that flocculation occurs primarily due to electrostatic attraction between slurry particles and the flocculants, and the bridging effect between the carboxylic groups in the side chains of xanthan gum molecule and the suspension particles. [ABSTRACT FROM AUTHOR]

As an energy-intensive industry, the energy and environmental issues of non-ferrous metals industry receive increasing attention. Dividing the production of non-ferrous metals into two sub-stages including mining and processing (M&P) and smelting and pressing (S&P), a non-cooperative game network data envelopment analysis model with double viewpoints (optimistic and pessimistic) is developed to evaluate the energy and environmental efficiency of China's non-ferrous metals industry. Moreover, we construct a novel network Malmquist productivity index to identify the dynamic evolution of energy and environmental performance. The results of 25 provinces over 2010–2017 show that energy and environmental efficiency of China's non-ferrous metals industry is very low during the study period, and the efficiency gap of two sub-stages increases significantly over time. Additionally, the energy and environmental efficiency in eastern region is more affected by the M&P sub-stage, while the efficiency of that in central and western regions is greatly influenced by the S&P sub-stage. Technical progress plays a key role in the productivity improvement of the M&P sub-stage, but the main driving force of productivity change in the S&P sub-stage is different in the three regions. Based on above findings, several targeted policy implications are suggested to prompt the sustainable development of China's non-ferrous metals industry. [ABSTRACT FROM AUTHOR]

Nonferrous metal is an essential natural resource for national economy and industry production. Understanding the supply, demand and price trend of nonferrous metal market is important to economic prosperity analysis and might contribute to electricity power consumption forecast. This research builds related market opinion indices to understand the supply, demand, and price changes in nonferrous metal market. We propose a self-learning graph neural network model-based sentiment index network method for value mining of sentiment-related features, addressing the issue of sentiment loss caused by discontinuities in domain-specific news. Based on the structured indicators and the integration of Internet sentiment indices, we establish two single-item models: Granger Causality-based ARDL Model (G-ARDL) and the Factor Analysis-based Transformer Model (F-Transformer). Finally, we construct a Bagging random sampling integration prediction framework to obtain the weight coefficients for single model predictions. We merge the prediction results in different single models with weighted fusion, resulting in smaller prediction errors compared to single models and equal-weight integration models. [ABSTRACT FROM AUTHOR]

In order to reduce the environmental impact caused by the migration of heavy metals in electrolytic manganese residue to water, this paper added calcined dolomite sand to electrolytic manganese residue to solidified Mn2+, and analyzed the microstructure and microstructure of dolomite sand before and after calcination by XRD, BET and SEM methods. The stabilization effect of calcined dolomite sand on Mn2+ in electrolytic manganese residue at different dosage was analyzed and evaluated. The results show that with the calcination temperature increasing from 600 °C to 800 °C, the dolomite sand gradually decompositions to form alkaline oxides such as CaO and MgO. The specific surface area, pore volume and pore size of calcined dolomite sand increase continuously, which are 1.16 ~ 3.96 times, 1.7 ~ 4.18 times and 1.99 ~ 16.12 times of uncalcined dolomite sand, respectively. When 10% calcined dolomite sand at 800 °C is added to electrolytic manganese residue, the stabilization efficiency of Mn2+ is 99. 95%, and when 30% calcined dolomite sand at 700 °C is added, the stabilization efficiency of Mn2+ is 99.85%, and the concentration of Mn2+ is as low as 1.66 mg/L. The stabilization effect of calcined dolomite sand on Mn2+ in electrolytic manganese residue is mainly that Mn2+ is solidified in the form of MnO2 and MnOOH. The calcined dolomite sand at 700 * 800 °C can be used as an effective stabilizer to solidified Mn2+ in electrolytic manganese residue. [ABSTRACT FROM AUTHOR]

Development of concrete as a construction material is most extensively used, around the world, leading to its inadvertent over exploitation. The extraction of the natural constituents of concrete, namely gravel and sand has a huge environmental impact. The insatiable demand for infrastructural development has led to the exploration of alternate constituents of concrete. The foundry industry waste can be a promising alternative to natural sand in concrete. In this article, the effectiveness of foundry sand, which is a byproduct of ferrous and non-ferrous metal casting industries having high silica content has been explored as a replacement for sand. The presence of silica in waste sand obtained from foundry draws attention towards its use in civil engineering applications such as partial replacement or full replacement of fine aggregate in production of concrete. Many studies have been performed on the use of waste foundry sand in concrete and concrete related items such as replacement of aggregate (fine), and bricks, blocks, and paving stones. The current study provides an idea about the scope of waste foundry sand utilization. It also yields the modification in physical, mechanical, microstructural, and durability properties of concrete. [ABSTRACT FROM AUTHOR]

Copyright of Nonferrous Metals (Mining Section) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Acid mine drainage (AMD) is recognized as one of the most serious contamination sources in the nonferrous metal mining industry. In this study, aerobic strains VCZ02 and VCZ09, which were identified as Leclercia adecarboxylata and Klebsiella aerogenes, were screened from 11 strains of copper-zinc-resistant bacteria in the soil of the Dexing copper mine with Cu2+/Zn2+ removal rates of 46.32%/41.03% and 57.96%/67.05%, respectively. The composition of extracellular polymers plays an important role in the removal of heavy metals by these two strains. A mixed community consisting of VCZ02 and VCZ09 was coupled with Sagittaria trifolia L.var.sinensis (Sims) Mak to construct a microbial-plant coupled reactor to remediate AMD. Under the optimal condition of sodium acetate as carbon source, the pH of AMD increased from less than 5 to above 6.5, showing Cu2+/Zn2+ removal rates of 70–80% and above 30%, respectively. SEM–EDS results showed that VZC02 and VZC09 in the coupled reactor also helped with resisting the toxicity of heavy metals to plants by forming biofilms on the root surface and increasing the content of heavy metals on the surface of roots, thus improving the treatment effect of plants. This study provides a theoretical basis for the bioremediation of AMD and its application. [ABSTRACT FROM AUTHOR]

The advanced nonferrous metal industry is a national strategic emerging industry, and its innovation ability is crucial to the transformation and development of downstream industries such as aerospace, rail transit, electronic information, and automobiles to the high end of the industrial value chain. The research on the evolution characteristics of its cooperative network is beneficial to the research on the mechanism of improving the innovation capability of the industry. Based on the cooperative invention patent application data in 2002–2020, using the social network analysis method and Gephi 0.9.2 visualization to construct a patent cooperation network and knowledge network, this paper analyzes the overall characteristics and evolution law of the patent cooperation network in the advanced nonferrous metal industry. It is found that, first, the structure of the innovation network in China's advanced nonferrous metals industry is becoming more and more complex. The scale of the cooperation network and knowledge network is increasing, and the small world is obvious. Second, some innovation subjects, as key nodes, play the role of "bridge" and grasp the general direction of technology. The structure of the key nodes in the network has changed, and the cooperative innovation network of industry-university-research has gradually evolved from enterprise-led to university-led. Third, the number of technical categories has increased and the depth of technology has been enhanced in China's advanced nonferrous metal field. Hot technical fields are characterized by high intensity, wide range, and stable advancement. Based on the research findings, some suggestions and enlightenment are put forward to promote the development of the advanced nonferrous metal industry. [ABSTRACT FROM AUTHOR]

In situ treatment of acidic arsenic-containing wastewater from the non-ferrous metal smelting industry has been a great challenge for cleaner production in smelters. Scorodite and iron arsenate have been proved to be good arsenic-fixing minerals; thus, we used lead slag as an iron source to remove arsenic from wastewater by forming iron arsenate and scorodite. As the main contaminant in wastewater, As(III) was oxidized to As(V) by H2O2, which was further mineralized to low-crystalline iron arsenate by Fe(III) and Fe(II) released by lead slag (in situ generated). The calcium ions released from the dissolved lead slag combined with sulfate to form well-crystallized gypsum, which co-precipitated with iron arsenate and provided attachment sites for iron arsenate. In addition, a silicate colloid was generated from dissolved silicate minerals wrapped around the As-bearing precipitate particles, which reduced the arsenic-leaching toxicity. A 99.95% removal efficiency of arsenic with initial concentration of 6500 mg/L was reached when the solid–liquid ratio was 1:10 and after 12 h of reaction at room temperature. Moreover, the leaching toxicity of As-bearing precipitate was 3.36 mg/L (As) and 2.93 mg/L (Pb), lower than the leaching threshold (5 mg/L). This work can promote the joint treatment of slag and wastewater in smelters, which is conducive to the long-term development of resource utilization and clean production. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Aksaray University Faculty of Economics & Administrative Sciences / Aksaray Üniversitesi Iktisadi ve Idari Bilimler Fakültesi Dergisi is the property of Aksaray University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

When producing seaweed for human consumption, incorporating a "Food Safety-by-Design approach" can help protect human health and ensure the safety of future consumers. Post-harvest processing of seaweed is one strategy to reduce undesirable compounds. The study aimed to determine the effects of a commercial processing strategy (blanching and fermentation) of Norwegian-harvested Saccharina latissima (sugar kelp) on the presence of prioritized food safety hazards. We compiled and prioritized food safety hazards to be analyzed based on the current impact of the hazard, the analytical feasibility, and the fit of the hazard to the case study site. Twelve prioritized hazards were included in the case study analyses: arsenic (total and inorganic), iodine, cadmium, lead, mercury, copper, zinc, the allergen tropomyosin, Salmonella spp., Bacillus spp., norovirus, and Vibrio spp. We found that blanching was very effective in reducing iodine concentrations but mildly increased the zinc concentration. Fermentation of blanched seaweed further decreased iodine concentrations and had similar effects on inorganic arsenic, cadmium, and zinc. An unintentional increase in copper was observed. Bacillus cereus was detected in a blanched sample and fermented samples. Vibrio alginolyticus seemed to be introduced during blanching, yet fermentation greatly reduced the detection frequency. Our study illustrates the importance of clearly defining the goals of seaweed processing and optimizing the process for food safety hazards. Meanwhile, it is advised to monitor for unintended effects that may occur during processing, such as, in our case, the introduction of copper and pathogens like B. cereus and Vibrio spp. This study serves as an example for seaweed stakeholders on how to consider a Food Safety-by-Design concept and a risk-based approach during seaweed harvest and post-harvest processing. • Industrial-scale seaweed processing was studied for various food safety hazards. • Blanching in warm seawater effectively reduced iodine. • Fermenting blanched seaweed decreased iodine, inorganic arsenic, cadmium, and zinc. • Copper was more frequently detected after fermentation. • Vibrio alginolyticus was detected less frequently in fermented seaweed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chemical plating and electroplating can be used to prepare ultra-thin copper–aluminum composite foils. • The process is shorter than the traditional aluminum-based copper plating process. • Preparation of transition layers by electroplating tin can form beneficial rivet structures. • The copper–aluminum composite foils have excellent bonding performance and electrical conductive properties. Copper-aluminum composite foils have the advantages of excellent electrical and mechanical properties, lightweight, and low cost. However, overcoming the equipment limitations of physical preparation methods to produce ultra-thin copper–aluminum composite foils with outstanding properties has been a challenge. Herein, smooth-faced, dense, and tightly bonded copper–aluminum composite foils are prepared using a combination of electroless plating and electroplating. This process involves the use of tin and nickel as transition layers, followed by electroplating the copper-clad layer. Ultra-thin copper–aluminum composite foils with a copper layer thickness ranging from 0.5 to 7 μm and a minimum square resistance of 4.6 mΩ can be prepared with a mass of 36.7 %-70 % of that of pure copper foils of the same thickness. These foils are expected to be used in a variety of energy storage components that require extreme lightweight. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesizing ring-shaped AMLROs active products with biomineralization method. • The mechanism of morphology evolution is investigated to optimize final materials. • Excellent electrochemical performance is achieved without cobalt and nickel. • The ring-shaped structure of AMLRO-54 is well maintained after long term cycling. As free from cobalt and nickel, all manganese-based lithium-rich layered oxides (AMLROs) are promising cathode materials with low cost and high theoretical energy density. This study introduced yeast as a biomineralization template to regulate the crystallization and growth of precursors at the molecular level. The mechanism of structural evolution was investigated in detail, offering a new approach to control the morphology of lithium-rich materials. The resulting AMLRO-54 exhibited a micro-nano composite ring-shaped structure with particle size around 2 μm. The unique hierarchical particles provided large flexible volume, leading to superior structural stability and high rate capability. The reversible capacity of ring-shaped AMLRO-54, without any other modifications, was 274.1 mAh·g−1 at 0.1 C. Once extra carbon material was added to improve the inferior electronic conductivity, the initial capacity of AMLRO-54 at 1 C reached 242.9 mAh·g−1 with a retention rate of 90.9 % after 300 cycles (221.0 mAh·g−1). Furthermore, this cobalt and nickel-free cathode material significantly mitigates material costs and environmental hazards, thereby promoting the development of lithium-ion batteries in the future. [ABSTRACT FROM AUTHOR]

• Integrating nZVI with bioprocess is highlighted for the treatment of contaminants. • Synergic interactions between the nZVI and the microbes are elucidated. • Theory and applications of the nZVI-bio system are reviewed. • Future and prospects of the integrated process are discussed. Integrating nanoscale zero-valent iron (nZVI) with biological treatment processes holds the promise of inheriting significant advantages from both environmental nano- and bio-technologies. nZVI and microbes can perform in coalition in direct contact and act simultaneously, or be maintained in separate reactors and operated sequentially. Both modes can generate enhanced performance for wastewater treatment and environmental remediation. nZVI scavenges and eliminates toxic metals, and enhances biodegradability of some recalcitrant contaminants while bioprocesses serve to mineralize organic compounds and further remove impurities from wastewater. This has been demonstrated in a number of recent works that nZVI can substantially augment the performance of conventional biological treatment for wastewaters from textile and nonferrous metal industries. Our recent laboratory and field tests show that COD of the industrial effluents can be reduced to a record-low of 50 ppm. Recent literature on the theory and applications of the nZVI-bio system is highlighted in this mini review. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of South China Fisheries Science is the property of South China Fisheries Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the rapid energy consumption increase in China's non-ferrous metal industry (NMI), there are inequalities in energy-related CO2 emissions among the sub-sectors. In this paper, a meta-frontier decomposition analysis was proposed for decomposing inter-structural low-carbon economic development inequalities among 29 sub-sectors in China's NMI from 2004 to 2018 into 11 components, including four new factors, i.e., energy- and output-oriented technological gaps and scale economies. In addition, an I(CI) index is constructed to measure the inter-inequalities of low-carbon economic development among NMI and decomposed from the static and dynamic perspectives, respectively. Results show that: (1) I(CI) index was in a downward trend during 2004-2010, while remained stable during 2010-2018; (2) the energy-oriented technological gap (ETG) was the key promoters to increase I(CI); (3) the potential energy intensity (PEI) was the primary inhibiting factor for I(CI); (4) the government can reduce the inter-inequalities by narrowing the technological gap and reducing potential energy intensity in the energy market. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the stress distribution that results from temperature changes in teeth restored with gold inlay and to predict the fatigue life of the teeth. A thermal load regimen for finite element analysis (FEA) was established in an in vivo experiment, in which participants with gold inlays drank hot and cold water. An extracted human maxillary molar was converted into a 3D FEA model. The tooth models with Class I and II preparations were restored with gold inlay in the experimental groups. The stress distribution was analyzed under the thermal loads. Also, lifetime prediction was conducted using Basquin's formulation. The gold inlay groups showed a higher stress distribution than the preparation-only groups regardless of the type of preparation. The Class II gold inlay group showed the shortest fatigue life of 2.48 x 1011 cycles, whereas the Class I preparation group showed the longest fatigue life of 4.49 x 1016 cycles. [ABSTRACT FROM AUTHOR]

Tungsten belongs to a group of refractory metals that possess extraordinary resistance to heat and wear and it is the heaviest engineering material. Because of its properties tungsten is used for special purposes. This paper presents the results of mechanical and microstructure research on the example of the characteristic heavy tungsten alloys 91W-6Ni-1,8Fe-1Co and 93W-5Ni-1,6Fe-0,3Co with different Ni/Co ratios. The proper Ni/Co ratio is important to obtain a favorable microstructure and mechanical properties of these materials. The distribution of the W, Ni, Co and Fe elements in tungsten phase and binder phase, which can influence on mechanical properties of tungsten alloys. The SEM analysis and the results of mechanical tests show that the alloy, which is within the exact limits of the Ni/Co ratio, has a finer microstructure and better mechanical properties, which is very important for maintaining the quality of tungsten alloys for special purposes. [ABSTRACT FROM AUTHOR]