Main Products Research Articles

In-depth exploration of waste printed circuit boards pyrolysis: Real-time products characteristics, kinetics parameter optimization and reaction mechanism

Pyrolysis is a promising technology for recycling waste printed circuit boards (WPCBs). This study delves into a real-time examination of the volatiles emitted from WPCBs during pyrolysis using thermogravimetric analysis coupled with Fourier transform infrared spectroscopy/mass spectrometry (TG-FTIR/MS), offering an in-depth analysis of the entire pyrolysis mechanism. An optimized kinetic model for printed circuit board (PCB) pyrolysis is developed by the shuffled complex evolution (SCE) algorithm. Results indicate that the main pyrolysis products are phenol and alkyl-substituted phenols, along with hydrogen bromide (HBr) and bromophenols. Bromides exhibit an earlier onset and peak temperature compared to phenolic products. The pyrolysis process can be divided into two stages: initial depolymerization of the resin body into macromonomers, followed by prevalent alkyl removal, homolytic reactions, and isomerization. The apparent activation energy (E) is 155.32 kJ/mol, the pre-exponential factor (ln(A)) is 29.77 min−1, and the kinetic mechanism function is described by (1‐α)2.02. This study provides crucial knowledge to advance the technology of WPCBs pyrolysis.

D-Electrons of Platinum Alloy Steering CO Pathway for Low-charge Potential Li-CO2 Batteries.

Aprotic Li-CO2 batteries suffer from sluggish solid-solid co-oxidation kinetics of C and Li2CO3, requiring extremely high charging potentials and leading to serious side reactions and poor energy efficiency. Herein, we introduce a novel approach to address these challenges by modulating the reaction pathway with tailored Pt d-electrons and develop an aprotic Li-CO2 battery with CO and Li2CO3 as the main discharge products. Note that the gas-solid co-oxidation reaction between CO and Li2CO3 is both kinetically and thermodynamically more favorable. Consequently, the Li-CO2 batteries with CoPt alloy-supported on nitrogen-doped carbon nanofiber (CoPt@NCNF) cathode exhibit a charging potential of 2.89 V at 50 µA cm-2, which is the lowest charging potential to date. Moreover, the CoPt@NCNF cathode also shows exceptional cycling stability (218 cycles at 50 µA cm-2) and high energy efficiency up to 74.6%. Comprehensive experiments and theoretical calculations reveal that the lowered d-band center of CoPt alloy effectively promotes CO desorption and inhibits further CO reduction to C. This work provides promising insights into developing efficient and CO-selective Li-CO2 batteries.

D‐Electrons of Platinum Alloy Steering CO Pathway for Low‐charge Potential Li‐CO2 Batteries

Aprotic Li‐CO2 batteries suffer from sluggish solid‐solid co‐oxidation kinetics of C and Li2CO3, requiring extremely high charging potentials and leading to serious side reactions and poor energy efficiency. Herein, we introduce a novel approach to address these challenges by modulating the reaction pathway with tailored Pt d‐electrons and develop an aprotic Li‐CO2 battery with CO and Li2CO3 as the main discharge products. Note that the gas‐solid co‐oxidation reaction between CO and Li2CO3 is both kinetically and thermodynamically more favorable. Consequently, the Li‐CO2 batteries with CoPt alloy‐supported on nitrogen‐doped carbon nanofiber (CoPt@NCNF) cathode exhibit a charging potential of 2.89 V at 50 µA cm‐2, which is the lowest charging potential to date. Moreover, the CoPt@NCNF cathode also shows exceptional cycling stability (218 cycles at 50 µA cm‐2) and high energy efficiency up to 74.6%. Comprehensive experiments and theoretical calculations reveal that the lowered d‐band center of CoPt alloy effectively promotes CO desorption and inhibits further CO reduction to C. This work provides promising insights into developing efficient and CO‐selective Li‐CO2 batteries.

Operando Spectroelectrochemistry Unravels the Mechanism of CO2 Electrocatalytic Reduction by an Fe Porphyrin.

Iron porphyrins are molecular catalysts recognized for their ability to electrochemically and photochemically reduce carbon dioxide (CO2). The main reduction product is carbon monoxide (CO). CO holds significant industrial importance as it serves as a precursor for various valuable chemical products containing either a single carbon atom (C1), like methanol or methane, or multiple carbon atoms (Cn), such as ethanol or ethylene. Despite the long-established efficiency of these catalysts, optimizing their catalytic activity and stability and comprehending the intricate reaction mechanisms remain a significant challenge. This article presents a comprehensive investigation of the mechanistic aspects of the selective electroreduction of CO2 to CO using an iron porphyrin substituted with four trimethylammonium groups in the para position [(pTMA)FeIII-Cl]4+. By employing infrared and UV/Visible spectroelectrochemistry, changes in the electronic structure and coordination environment of the iron center can be observed in real-time as the electrochemical potential is adjusted, offering new insights into the reaction mechanisms. Catalytic species were identified, and evidence of a secondary reaction pathway was uncovered, potentially prompting a re-evaluation of the nature of the catalytically active species.

A Carbon Capture and Utilization Process for the Production of Solid Carbon Materials from Atmospheric CO2 - Part 2: Carbon Characterization.

This article is the second part of a study reporting the results of a novel carbon capture and utilization (CCU) process, which converts atmospheric CO2 into solid carbon materials. The CCU process combines direct air capture (DAC) with catalytic methanation, which is then followed by methane pyrolysis in a reactor filled with liquid tin. While Part 1 discussed the performance of the overall process and individual process steps regarding conversions and yields, Part 2 characterizes the solid carbon products obtained under various synthesis conditions. The effects of the pyrolysis temperature and the composition of the gas mixture from the methanation step on the solid carbon product are analyzed. Carbon powder is synthesized from methane with either H2 or CO2 as most important impurity. Carbon samples are characterized using SEM, TEM, Raman spectroscopy, XPS and XRD analysis. Very thin, disordered carbon flakes, soot aggregates and large carbon onions are identified as the main solid products of the process. Their formation mechanisms in the liquid metal-filled pyrolysis reactor are discussed.

Winter wheat identification in China through FY-3D NDVI&EVI satellite data and DNN Fusion

ABSTRACT Medium Resolution Spectral Imager-II (MERSI-II) on FengYun 3D (FY-3D) meteorological satellite is a visible and infrared spectral imaging instrument comparable with Moderate Resolution Imaging Spectroradiometer (MODIS), which provides ample opportunities for regional crop mapping. However, current research may have overlooked the potential of combining FY-3D MERSI-II data with deep neural network (DNN) algorithms for winter wheat identification. This research utilizes a DNN method to train a nonlinear model with the synthetic normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI) at a 250 m resolution from FY-3D MERSI-II as the eigenvalues, enabling to accurately identify spatial distribution of winter wheat in China’s main production regions and filling the gap in the application of FY-3D MERSI-II data. The results indicate that the winter wheat identification with the combination of NDVI and EVI achieved an accuracy of 95.32%, with a Kappa coefficient of 0.87 and a determination coefficient (R 2 ) of 0.73, improving the overall accuracy by 1.27% and 1.07% compared to models trained solely using NDVI or EVI, respectively. In terms of spatial distribution, the overlap rate with the winter wheat dataset of China from MODIS at a 500 m resolution exceeded 95%, with an area bias of 2.67%. This study indicates that the medium resolution FY-3D MERSI-II remote sensing dataset combined with the DNN algorithm can accurately identify crop information over large areas.

Managing the Nutraceutical and Sensorial Qualities of Pisanello, an Ancient Tomato Landrace, in Soilless Conditions

Recently, there has been significant consumer demand for traditional tomato varieties due to their favourable organoleptic qualities; however, the cultivation of these ancient varieties is becoming more restricted due to inadequate shelf life and low productivity. The “Pisanello” is a Tuscany tomato variety mainly cultivated in the provinces of Pisa, Lucca, and Livorno, and the main producers of this ancient tomato are small local farmers. The purpose of this work was, firstly, to study the range of quality parameters of this landrace tomato grown using different cultivation techniques, both in soil and soilless systems. For this purpose, the physicochemical parameters of Pisanello tomatoes grown in six different farms in Tuscany using both soilless and soil methods were investigated. Secondly, Pisanello tomatoes grown using different soilless techniques (rockwool and aeroponics) and soil-grown tomatoes (Pisanello and Goldmar F1) were evaluated from organoleptic and nutraceutical points of view. The sensory profile evaluation of all types of tomatoes under investigation was carried out. The aeroponic cultivation of Pisanello induced higher organoleptic qualities than those of tomatoes cultivated in rockwool (+34% for titratable acidity and +18% for total soluble solids). On the other hand, soilless rockwool-grown tomatoes showed a better sensory profile with respect to aeroponic cultivation. Nevertheless, the Goldmar F1 tomato, morphologically similar to ‘Pisanello’, received lower scores from the sensory panel compared to the Tuscany landrace tomato. This indicates that ancient tomato varieties selected over decades remain the preferred choice for consumers. Therefore, from a long-term viewpoint, the valorisation of local tomato varieties such as Pisanello can promote the regional commercialization of novel niche products originating from ancient fruit thanks to their acceptability by consumers.

Monocyte-regulated interleukin 12 production drives clearance of Staphylococcus aureus.

Staphylococcus aureus is a versatile bacterium responsible for conditions ranging from mild skin and soft-tissue infections to serious disorders such as pneumonia and sepsis. Monocytes play a role in protection against pathogens by migrating to inflamed tissues and differentiating into macrophages but their specific role in the context of S. aureus pulmonary infection has not been fully elucidated. Using a CCR2-DTR transgenic mouse model we demonstrate that over the course of infection monocyte depletion resulted in worse airway clearance of S. aureus. The bronchoalveolar lavage fluid (BALF) of CCR2-DTR mice after S. aureus infection displayed significant decreases in interleukin-12 (IL-12), IFN-γ, IP-10, MIG and RANTES, all IFN-γ regulated, compared to wild-type (WT) infected controls. NK cells were identified as the main producers of IFN-γ, but both NK cells and IFN-γ were dispensable for clearance. We demonstrated through cytokine production and RNA-seq analysis that IL-12 and IL-12 regulated genes are strongly induced in monocytes upon S. aureus infection. Administration of IL-12 during infection restored the bacterial burdens in the BALF and lungs of monocyte-depleted CCR2-DTR mice to the levels of WT mice, independent of IFN-γ. In the absence of monocytes, alveolar macrophages are the primary phagocytic cells, and IL-12 influences their capacity to produce reactive oxygen species and clear S. aureus. These results show that production of IL-12 contributes to the control of S. aureus via its influence on alveolar macrophage function.

Establishment, Multiplication, and Biochemical Analysis of Embryogenic Lines of the Amazonian Palm Euterpe precatoria Mart. under Suspension Culture

The palm Euterpe precatoria holds great social, cultural, and environmental importance. The heart of palm and the fruit are the main products used for industrialization due to their energetic properties. Thus, the aim of this study was to establish a suspension cultivation protocol for the species using different explant sources. For this, eight lineages of E. precatoria embryogenic calluses were tested, with five in liquid medium Murashige and Skoog (MS) with 5 μM Picloram and three for comparison in semisolid medium MS with 20 μM Picloram and 5 μM 2iP. The growth curve was obtained by weighing the calli from 60 to 180 days of cultivation. The Gompertz model was applied, and growth kinetics were evaluated. At 100 days, the contents of total soluble sugars (TSSs) and total soluble proteins (TSPs) were determined. Principal components (PCA) were measured. According to the analysis of the data, the cultivation of E. precatoria lineages in liquid medium was successfully carried out, and the establishment was achieved. The model can be considered adequate since the R2 values found describe more than 90% of the growth kinetics of the lineages. In the liquid system, lineages L1 (from leaf explants and multiplied in semisolid medium—SM), L2 (from leaf explants and multiplied in SM), and L6 (from zygotic embryo explants and multiplied in liquid medium—LM) showed the shortest time to double the biomass accumulation. Multivariate analysis reveals a significant increase in masses in liquid cultures, represented by lineages L6 and L2. There was statistical difference in the amount of TSSs extracted; the highest TSS levels were observed in lineages cultivated in LM. The protein content found was very low, showing statistical differences among the lineages. In this work, the establishment and multiplication of embryogenic calli of E. precatoria are described for the first time, and they emerge as viable alternatives for the vegetative propagation of the species.

Reconciling plant and microbial ecological strategies to elucidate cover crop effects on soil carbon and nitrogen cycling

Abstract Plant economics, the way plants allocate and utilize resources, affect multiple soil processes through interactions with root and associated microbial communities. However, the interplay between plant economics and microbial ecological strategies remains poorly understood, which is crucial for integrated manipulation of plant‐ and microbe‐mediated functions in mitigating climate change and sustaining soil health. We used a field experiment with 11 cover crop species grown monocultures in the same base soil to test whether microbial ecological strategies are associated with plant economic strategies and if their interactions are linked to soil functions. A principal component analysis (PCA) was performed on root and leaf traits to identify the loadings of cover crop species on the plant trait space. Metagenomic analysis of rhizosphere microbial communities was conducted to infer their ecological strategies based on genetically encoded community‐aggregated traits. We found a synchronous relationship between the conservation gradient of plant economic strategies and the trade‐offs in microbial ecological strategies. Conservative plant strategists, such as Lolium multiflorum, Triticum turgidum and Brassica juncea, fostered microbial communities characterized by high growth yield potentials (Y‐strategies). This included increased microbial carbon fixation pathways, citrate cycle, ribosome and valine, leucine and isoleucine biosynthesis. As a result, microbial metabolic efficiency improved, shown by higher microbial biomass carbon content and a lower metabolic quotient (qCO2), led to enhanced soil organic carbon accumulation. In comparison, acquisitive plants like Astragalus sinicus, Vicia villosa, Trifolium incarnatum and Medicago sativa stimulated microbial resource‐acquisition strategies (A‐strategies). This included enhanced bacterial chemotaxis, secretion systems, biotin metabolism and cell motility pathways, which in turn increased soil exoenzyme activity and accelerated soil nitrogen mineralization. Consequently, these species enhanced soil nitrogen availability and had substantial feedbacks on subsequent main crop productivity. Synthesis. This study demonstrates how plant economic strategies influence the balance between different microbial ecological strategies, specifically the trade‐offs in Y‐ and A‐strategies. These interactions exert control over carbon and nitrogen dynamics in the soil ecosystem. The findings provide insights for implementing nature‐based solutions to improve agroecosystem management practices.

Exploration of steel slag by lignin and sodium citrate modification for mechanical properties and stability of steel slag-cement cementitious materials

Steel slag is produced globally in huge annual quantities. How to achieve its large-scale utilization is a question that researchers have been exploring. In this work, sodium citrate (SC) was used as a linker to modify Steel slag (SS) with alkali lignin (AL). And steel slag cement cementitious materials (CSS) were prepared with 10% replacement ratio. The effects of AL and SC on CSS were investigated by X-ray diffractometry (XRD), Fourier Transform Infrared Spectroscopy (FT-IR) and Thermo-gravimetric analysis (TG/DTA) etc. The results indicated that AL successfully loaded on the surface of SS. For CSS, as the degree of modification increased, the standard consistency water consumption of CSS decreased from 27% to 23.5%. During the hydration of CSS, its main hydration product was Ca(OH)2, the suitable amounts of AL and SC can stimulate the activity of SS. In addition, SS modification could improve the stability of CSS. The results of Ray's clamp method showed that the addition of AL and SC made the expansion of CSS reduced from 1.5 to 0. The 3 d and 28 d of CSS maximum flexural strengths were 5.42 MPa and 8.61 MPa and the maximum compressive strengths were 22.96 MPa and 49.15 MPa, respectively. This was an increase of 36.67% and 48.27% respectively. Therefore, the combination of AL and SS can not only effectively solve the problem of AL resource utilization, but also is expected to realize the practical application of SS in cement cementitious materials. It has good social and environmental benefits.

Towards Sustainable Productivity of Greenhouse Vegetable Soils: Limiting Factors and Mitigation Strategies.

Greenhouse vegetable production has become increasingly important in meeting the increasing global food demand. Yet, it faces severe challenges in terms of how to maintain soil productivity from a long-term perspective. This review discusses the main soil productivity limiting factors for vegetables grown in greenhouses and identifies strategies that attempt to overcome these limitations. The main processes leading to soil degradation include physical (e.g., compaction), chemical (e.g., salinization, acidification, and nutrient imbalances), and biological factors (e.g., biodiversity reduction and pathogen buildup). These processes are often favored by intensive greenhouse cultivation. Mitigation strategies involve managing soil organic matter and mineral nutrients and adopting crop rotation. Future research should focus on precisely balancing soil nutrient supply with vegetable crop demands throughout their life cycle and using targeted organic amendments to manage specific soil properties. To ensure the successful adoption of recommended strategies, socioeconomic considerations are also necessary. Future empirical research is required to adapt socioeconomic frameworks, such as Science and Technology Backyard 2.0, from cereal production systems to greenhouse vegetable production systems. Addressing these issues will enable the productivity of greenhouse vegetable soils that meet growing vegetable demand to be sustained using limited soil resources.

Corrosion failure analysis of steel tubes operating in mining installations: Metallurgical, chemical and mechanical investigations

AbstractCorrosion of steel tubes represents a major challenge for various industries, leading to significant economic and environmental impacts, such as material losses, operational interruptions and safety risks. This study focuses on the metallurgical, chemical and mechanical characterization of corroded steel tubes operating in mining installations using metallographic analysis, X-ray diffraction (XRD), SEM-EDS studies, chemical analysis and micro-hardness measurements. The results reveal the existence of a considerable extent of corrosion, of which, the main corrosion products are magnetite – 72% and goethite – 18.1 associated with corrosion. The corroded tubes measured 0.128% carbon, against 0.23% in new tubes, indicating a loss in weight and mechanical strength properties. The observed tensile strength for the new tubes was 481 MPa while the same for the corroded tubes was to a large extent lower. Furthermore, metallographic examination indicates that indeed the structure is ferrite pearlite as to the composition. This study indicates that 304 L or 316 L stainless steels may be utilized which have better corrosion-protecting coatings thus prolonging service life and reducing maintenance activities.

Goblet cell differentiation subgroups in colorectal cancer

The poor prognosis of relatively undifferentiated cancers has long been recognized, suggesting that selection against differentiation and in favor of uncontrolled growth is one of the most powerful drivers of cancer progression. Goblet cells provide the mucous surface of the gut, and when present in colorectal cancers (CRC), the cancers are called mucinous. We have used the presence of MUC2, the main mucous product of goblet cells, and an associated gene product, TFF3, to classify a large panel of nearly 80 CRC-derived cell lines into five categories based on their levels of MUC2 and TFF3 expression. We have then shown that these five patterns of expression can be easily identified in the direct analysis of tumor specimens allowing a much finer characterization of CRCs with respect to the presence of goblet cell differentiation. In particular, about 30% of all CRCs fall into the category of expressing TFF3 but not MUC2, which has not previously been acknowledged. Using the cell line data, we suggest that there are up to 12 genes (MUC2, TFF3, ATOH1, SPDEF, CDX1, CDX2, GATA6, HES1, ETS2, OLFM4, TOX3, and LGR5) that may be involved in selection against goblet cell differentiation in CRC by changes in methylation rather than mutations. Of these, LGR5, which is particularly associated with lack of goblet cell features, may function in the control of differentiation rather than direct control of cell growth, as has so far mostly been assumed. These results emphasize the importance of methylation changes in driving cancer progression.

Economic and Environmental Effects of Farmers’ Green Production Behaviors: Evidence from Major Rice-Producing Areas in Jiangxi Province, China

This study examines the economic and environmental impacts of green production practices among farmers. It aims to contribute to sustainable agricultural development, mitigate agricultural non-point source (NPS) pollution, and align environmental protection with economic growth. This paper utilizes survey data from 1345 farm households in the main rice production areas of Jiangxi Province, China, using the example of reduced fertilizer application (RFA) among rice farmers. This study constructs a slack-based measure data envelopment analysis (DEA—SBM) model with undesirable outputs to measure environmental effects and applies an endogenous switching regression model (ESRM) to test the economic and environmental effects of farmers’ adoption of green production technologies. We found the following: (1) The RFA behavior of farmers has a significant positive impact on their net profit per hectare (NPH), helping farmers increase their income, with the increase ranging from 2.05% to 6.54%. (2) Farmers’ RFA behavior has a significant positive impact on agricultural green productivity (AGP), contributing to the improvement of the environment, ranging from 44.09% to 45.35%. (3) A heterogeneity analysis found inconsistencies in the income-enhancing and environmental-enhancing effects at different quantiles of NPH and AGP. Therefore, attention should be placed on improving the agricultural product quality supervision system under the market circulation mechanism, creating land scale conditions conducive to the promotion and application of fertilizer reduction technologies and promoting the implementation of externality internalization compensation systems.

Heatwave Intensifications in Armenia: Evidence From Temporal and Spatial Analysis of Observational Data Over the Last Decades

ABSTRACTIncreasing temperatures cause the weather to become more severe. Studying how heatwaves (HWs) impact individual heat exposure and susceptibility is vital for building climate change mitigation and adaptation measures. So, this study explores the impact of HWs on individual heat exposure and susceptibility. The assessment was based on the highly complex topographic region contribution to HWs in the Republic of Armenia (RA) using data from 16 meteorological stations for the extended warm season (May–September). We developed a regional HW catchment program to estimate the HW indices' responses to climatic change and to present them in terms of topography changes. The Mann–Kendall (MK) test was used to determine the statistical significance of the trends for 10 distinct HW indicators using linear and exponential trends along with graphical interpretations. This study reveals a large‐scale, significant increasing trend in annual maximum temperatures (Tmax) and observed HWs over the period 1955–2019. The rising temperature is accompanied by an increase in HW indices, particularly at low altitudes up to 1250 m above sea level (ASL), where the main population centres and national crop production are concentrated. According to our classification, the above‐mentioned areas have faced extreme and severe increases in HW intensity, covering more than 60% of the country's territory. Moreover, not only the intensity and frequency have been identified but the HW period extension as well. This extreme increase has been found in the low‐lying highly populated and intensively cultivated areas, such as in the Ararat valley. These results have implications for future climate assessments, adaptation strategies, agriculture and public health in Armenia. The development of targeted mitigation measures and adaptation strategies informed by these findings is essential for addressing the escalating challenges posed by HWs in the region.

The influence of major faults and fractures on the development of non-matrix porosity system in a pre-salt carbonate reservoir, Santos Basin – Brazil

Faults and fractures are central for characterizing the permeability distribution in carbonate reservoirs since they act as pathways for diagenetic fluids that often favor intense rock dissolution and permeability. Usually, high permeability zones and fractures are not easily recognized in seismic data due to limited resolution and they are often associated with higher concentrations of hydrocarbons or even significant fluid losses during drilling, thus creating a challenge for hydrocarbon exploration. In the Santos Basin, southeast Brazil, the pre-salt carbonate reservoirs from the Barra Velha Formation (BVE) are the main hydrocarbon producers in Brazilian Atlantic margin and well-known for being extremely heterogeneous, exhibiting complex dual-porosity systems. In this study, we built a conceptual model of these fracture zones and non-matrix porosity formation that helped narrowing the understanding of these complex systems. The characterization of faults and fractures was carried out using seismic, well-logs, and borehole image data to understand the influence of these structures in the porosity formation along the Barra Velha Formation. In the study area, three fault sets were defined (F1, F2, and F3) from seismic data. F1 represents to the larger faults, while the F3 fault set represents the smaller faults related to the reactivation of F1; both sets being oriented NE-SW. The F2 fault set is associated with the rift formation and is oriented to NNE-SSW. These three fault sets compartmentalized the studied area into different domains, each exhibiting distinct fracture sets. The natural open fractures were formed during the reactivation of rift faults and are oriented mainly NW, NNE-NNW, NE, and ENE and were identified across the entire study area, but with different intensity values. The fracture intensity closely relates to the distance from major faults where the wells with the highest fracture intensity occurs located 150–590 m from the larger F1 fault set. Scan-lines were conducted throughout the area to determine the fault width, and an average value of 1.2 km was established. Seven non-matrix porosity classes were characterized and classified into stratigraphically concordant and discordant non-matrix pore types at well scale through borehole image interpretation. The Barra Velha Formation exhibit higher occurrence of stratigraphically discordant non-matrix porosity related to fractured zones while stratigraphically concordant non-matrix porosity is mainly controlled by the paleotopography of the study area. Overall, non-matrix porosity formation tends to follow an orientation that suggests a preferential dissolution flow towards NE and ENE directions. Intervals with higher silica content shows a positive correlation with both fracture intensity and stratigraphically discordant non-matrix porosities. This work provides a conceptual model about the fractures and non-matrix porosity distribution in pre-salt carbonate rocks that can help address some of associated structural and stratigraphic uncertainties during field appraisal and development.

Study on the Characteristics of Molten Glass in a Float Glass Process with a New Structure.

Glass is one of the most common materials in society, and the float glass process is the main production method of glass used at present, which involves adopting a melting furnace with a single cooler. However, this structure has been difficult to fit to the requirements of modern glass production, such as producing multiple types of glass and large-scale production. Therefore, a large-tonnage float glass melting furnace with a double cooler is studied, which is rising in popularity in the glass sector. The aim of this paper is to clarify the characteristics of the new glass furnace. A numerical simulation technique is applied to analyze the thermal and flow characteristics of molten glass in the new structure so as to clarify the feasibility of production by checking the temperature distribution and flow field of the molten glass. The results show that the new structure also exhibits flow behavior similar to the original structure in the branch line. Due to the addition of the branch line, the stability of the temperature is improved, with a 60 K and 43 K difference between the surface and bottom in the main and branch lines, respectively. Similar stability is shown in the flow field, specifically low acceleration in the cooler (0.006 m/s2). The bubble clarification time is about 2700 s, less than the 3000 s required for flow. The parameters of the branch line meet the requirements of glass production. In theory, a glass-melting furnace with a double cooler has the capacity to produce two types of glass.

Production of 1,4-butanediol through Clostridia C4 pathways

1,4-butanediol (1,4-BDO) is an important building block in the chemical industry that has been mainly produced from fossil fuels, but now biosynthesis of 1,4-BDO has received more and more attention due to environmental issues. The Clostridia C4 pathway produces an intermediate crotonyl-CoA which could be diverted to 1,4-BDO by 4-hydroxybutyryl-CoA dehydratase (4HBD). Here, we compared this pathway with other 1,4-BDO biosynthesis pathways and illustrated its potential advantages regarding cellular energy conservation and theoretical yield. Then, the feasibility of 1,4-BDO production in this way was tested by introducing a single 4HBD in Clostridium acetobutylicum that natively produced the C4 intermediate and a variety of aldehyde/alcohol dehydrogenases (AdhE). Five different 4HBD genes were screened and the Cbei-2100 gene from Clostridium beijerinckii was the most effective, producing 0.066 mg/mL of 1,4-BDO. To block the metabolic flux towards the main product butanol, disruption of butyryl-CoA dehydrogenase (Bcd) was tried but failed, while inactivation of its homologue (FAD/FMN-containing dehydrogenase, Fcd) obtained little effect. Alternatively, the electron-transferring flavoprotein EtfA coupled with Bcd was inactivated, and 1,4-BDO production was greatly increased to 0.182 mg/mL. In conclusion, this study demonstrated the feasibility of 1,4-BDO production through the Clostridia C4 pathway. Further blocking of the competing flux towards butanol would be effective to improve the production of in the future.

Earth-Abundant CuWO4 as a Versatile Platform for Photoelectrochemical Valorization of Soluble Biomass Under Benign Conditions.

Here, a nanosheet-structured CuWO4 (nanoCuWO4) is demonstrated as a selective and stable photoanode for biomass valorization in neutral and near-neutral solutions. nanoCuWO4 can be readily prepared by a solid phase reaction using nanosheet-structured WO3 as the template. Several substrates, including glucose, fructose and glycerol, are investigated to reveal the wide applicability of nanoCuWO4. The activity and product distribution trends in biomass valorization are investigated at different pH by taking advantage of the promising stability of nanoCuWO4 in a wide pH range. Product analyses confirm that formate production with a Faradaic efficiency (FE) of 76 ± 5% and glycolate production with an FE of 61 ± 8% can be achieved by glucose and fructose valorization at pH 10.2, respectively. On the other hand, glyceraldehyde and dihydroxyacetone (DHA)are the main products in the glycerol valorization, accounting for an FE of over 85% at pH 7. Notably, nanoCuWO4 has the highest FE of DHA in photoelectrochemical (PEC)glycerol valorization compared to WO3 and BiVO4 at neutral pH. The oxidation routes and mechanism of glycerol valorization on nanoCuWO4 are also under investigation. The co-production of H2 and value-added chemicals is finally demonstrated using a photovoltaic cell connected to a nanoCuWO4-based PEC glycerol valorization system.