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【Objective】Establishing a universal PCR detection system would address the issue of inconsistent amplification systems and reaction conditions of different events, thereby enhancing the efficiency of event detection.【Method】In this study, we analyzed and compared the differences in amplification systems and reaction conditions of qualitative and quantitative PCR detection methods for the specificity of transgenic material events. The most widely used PCR systems and conditions parameters were selected as unified parameters to validate the PCR qualitative detection methods for different maize events in the laboratory.【Result】General PCR amplification system: Total volume 25.0 μL, 25 mmol/L MgCl2 solution 1.5 μL, 2.5 mmol/L dNTPs mixed solution 2.0 μL, final concentration of upstream and downstream primer 0.4 μmol/L, Taq DNA polymerase 0.025 U/μL, 25 mg/L DNA template 2.0 μL, LOD 0.1%. Reaction conditions: Denaturation at 94℃ for 5 min, 35 cycles of denaturation at 94℃ for 30 s, annealing at 58℃ for 30 s, extension at 72℃ for 30 s, and final extension at 72℃ for 7 min. Universal real-time fluorescent qualitative PCR amplification system: Total volume 20.0 μL, 25 mmol/L MgCl2 solution 2.0 μL, dNTPs mixed solution (2.5 mmol/L each) 1.6 μL, final concentration of upstream and downstream primers and probe 0.4 μmol/L, Taq DNA polymerase 0.04 U/μL, 25 mg/L DNA template 2.5 μL, LOD 0.1%. Reaction conditions: denaturation at 95℃ for 5 min; 95℃ denaturation 15 s, 60℃ annealing extension 60 s, 40 cycles.【Conclusion】This system and its associated amplification system and reaction conditions can be used to detect different event materials. [ABSTRACT FROM AUTHOR]

Diesel reforming is a promising hydrogen production technology used for the clean energy conversion of high-carbon-content fuels. Although the reaction system has been established, predicting the optimal reaction conditions for the system remains challenging. Here, we obtained a set of 675 data points from Aspen Plus simulations and trained regression models to predict the reaction condition ranges that yield the highest hydrogen production in diesel reforming. The ETR model achieved the best predictive performance, with an R2 value of 0.99. Interpretable machine learning methods revealed that temperature is a crucial feature determining the baseline hydrogen yield of the diesel reforming reaction, while the steam-to-carbon ratio is key to enhancing hydrogen yield. Our exploratory study underscores the ability of data-driven ML models to uncover the condition-yield relationship in catalytic diesel reforming for hydrogen production by isolating the effects of individual design parameters, a feat that is difficult to achieve through experimental means. [Display omitted] • Research methods combining Aspen Plus simulation and machine learning. • Interpretable machine learning models with deep analytical capabilities. • Obtain guidance intervals for reaction conditions that can be directly used. • Machine learning with minimal prediction and experimental errors. [ABSTRACT FROM AUTHOR]

Tea is one of the most important parts of agricultural production in China. A large amount of waste tea residues can be produced every year with the continuous growth of the tea industry. Waste tea residue shares significant economic and medicinal value, due to its bioactive substances, especially caffeine. However, most waste tea residues cannot be fully utilized in a resourceful way, resulting in the waste of resources and pressure on the environment. In this study, an efficient caffeine extraction was proposed using hydrothermal extraction. A systematic investigation was implemented to explore the effects of different factors on extraction efficiency. Response surface ology (RSM) and artificial neural network (ANN) were also combined to optimize and predict the extraction conditions. Firstly, the efficient extraction of caffeine from tea residue was achieved by hydrothermal extraction. The special properties of water were exploited under high temperature and pressure. As such, the lignocellulose structure in tea residues was effectively destroyed to obtain the dissolution of active substances, such as caffeine. The high efficiency and environmental advantages of hydrothermal approaches were emphasized to treat the wet biomass under mild conditions, compared with the conventional one. The better performance was achieved in the high efficiency, low energy consumption, and reduced use of hazardous chemical solvents. Secondly, the key parameters of extraction (hydrothermal temperature, time, liquid-solid ratio, and pH) were systematically analyzed using RSM. The influencing level of each factor on the caffeine extraction was determined to derive the optimal extraction conditions. The experimental results showed that the hydrothermal temperature shared the most significant effect on the caffeine extraction. The extraction efficiency was significantly improved to appropriately increase the hydrothermal temperature. An ANN model was also established to further validate and optimize the extraction conditions. A large amount of experimental data was trained and then validated to learn and simulate complex nonlinear processes. The ANN model was also used to accurately predict caffeine extraction under different conditions. The prediction of the ANN model showed that the optimal extraction conditions were determined as the hydrothermal temperature of 220 °C, hydrothermal time of 3.5 h, liquid-solid ratio of 50 mL/g, and pH 9.0. A caffeine extraction of 66.19 mg/g was expected to be obtained. There was high agreement with the actual experiment (65.81 ± 0.47 mg/g), indicating a high prediction accuracy. The ANN model was verified to optimize and predict the caffeine extraction from waste tea residue, in terms of the high feasibility and accuracy. In conclusion, the organic solvents were avoided to be environmentally friendly and realize green chemistry, indicating the promising potential for the extraction of natural products. Meanwhile, the efficient extraction of caffeine from waste tea residue can provide a useful reference for the high-value recycling of waste biomass resources using RSM and ANN models. The environmental pressure can be alleviated to reduce the waste of resources for the considerable economic benefits in the tea industries. [ABSTRACT FROM AUTHOR]

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Hydrothermal liquefaction (HTL) of microalgae produces a biofuel with high nitrogen and oxygen content, leading to the emission of NOX gases which are environmental pollutants. A high N and O content also reduces the high heating value (HHV) and energy recovery (ER) of the fuel. This research aimed at reducing the N, O, and S contents of the biocrude oil by assessing the impact of reaction conditions on de-nitrogenation, de-oxygenation, de-sulphurisation, and on the biocrude yield in the presence and absence of Zn ferrite magnetic nanoparticles (MNPs). The MNPs played a microalgae separation role and a catalytic role. The reaction conditions assessed included holding time, HTL under a hydrogen atmosphere, and HTL under 5% formic and 5% sulphuric acid. An increase in holding time resulted in a gradual increase in bio-crude yield up to a maximum yield of 36.2 wt.% after 60 min. An increase in holding time also led to a gradual increase in carbon and hydrogen content of biocrude oil and to a steady reduction in O, N, and S contents. Liquefaction in the presence of 5% sulphuric acid resulted in the highest removal of nitrogen by 83 wt.% and the highest hydrogen content (10.6 wt. %) for all liquefaction experiments. According to GC–MS results, HTL under a hydrogen atmosphere resulted in increased removal of oxygenated compounds and an increase in hydrocarbon content of biocrude oil. The MNPs used for microalgae separation and catalytic HTL were synthesised using the co-precipitation process and characterised using HRTEM. An increase in the H and C contents and a reduction in the N, O, and S contents of bio-crude oil greatly improve its quality and energy value, hence its potential for use as a transportation fuel. [ABSTRACT FROM AUTHOR]

Liquefaction conversion technology has become one of the hottest biomass conversion methods due to its flexible material selection and extensive product applications. Exploring biomass liquefaction conversion focuses on catalysts, biomass/water ratio, and reaction temperature. However, it is found that solvents are crucial in the biomass liquefaction process and significantly impact the type of liquefied products and bio-oil yield. Given the current rapid development trend, timely sorting and summary of the solvent effect in the biomass liquefaction process can promote the subsequent development and industrialization of more efficient and cleaner biomass liquefaction technology. Therefore, this review first introduces the characteristics of water as the liquefaction solvent, then summarizes the effects of organic solvents on liquefaction, and finally elaborates on the synergistic effect of co-solvents, which provides a more systematic overview of solvent effects in the liquefaction process. Meanwhile, prospects are put forward for the future development of biomass liquefaction conversion. [ABSTRACT FROM AUTHOR]

Abstract The challenge of devising pathways for organic synthesis remains a central issue in the field of medicinal chemistry. Over the span of six decades, computer-aided synthesis planning has given rise to a plethora of potent tools for formulating synthetic routes. Nevertheless, a significant expert task still looms: determining the appropriate solvent, catalyst, and reagents when provided with a set of reactants to achieve and optimize the desired product for a specific step in the synthesis process. Typically, chemists identify key functional groups and rings that exert crucial influences at the reaction center, classify reactions into categories, and may assign them names. This research introduces Rxn-INSIGHT, an open-source algorithm based on the bond-electron matrix approach, with the purpose of automating this endeavor. Rxn-INSIGHT not only streamlines the process but also facilitates extensive querying of reaction databases, effectively replicating the thought processes of an organic chemist. The core functions of the algorithm encompass the classification and naming of reactions, extraction of functional groups, rings, and scaffolds from the involved chemical entities. The provision of reaction condition recommendations based on the similarity and prevalence of reactions eventually arises as a side application. The performance of our rule-based model has been rigorously assessed against a carefully curated benchmark dataset, exhibiting an accuracy rate exceeding 90% in reaction classification and surpassing 95% in reaction naming. Notably, it has been discerned that a pivotal factor in selecting analogous reactions lies in the analysis of ring structures participating in the reactions. An examination of ring structures within the USPTO chemical reaction database reveals that with just 35 unique rings, a remarkable 75% of all rings found in nearly 1 million products can be encompassed. Furthermore, Rxn-INSIGHT is proficient in suggesting appropriate choices for solvents, catalysts, and reagents in entirely novel reactions, all within the span of a second, utilizing nothing more than an everyday laptop.

Despite their widespread applications in sectors such as pulp and paper, textile, food and beverage, pharmaceuticals, and biofuel production, laccases encounter challenges related to their activity and stability under varying reaction conditions. This review accumulates data on the complex interplay between laccase characteristics and reaction conditions for maximizing their efficacy in diverse biotechnological processes. Benefits of organic media such as improved substrate selectivity and reaction control, and their risks such as enzyme denaturation and reduced activity are reported. Additionally, the effect of reaction conditions such as pH and temperature on laccase activity and stability are gathered and reported. Sources like Bacillus pumilus, Alcaligenes faecalis, Bacillus clausii, and Bacillus tequilensis SN4 are producing laccases that are both thermo-active and alkali-active. Additionally, changes induced by the presence of various substances within reaction media such as metals, inhibitors, and organic solvents are also reported. Bacillus pumilus and Bacillus licheniformis LS04 produce the most resistant laccases in this case. Finally, the remarkable laccases have been highlighted and the proper laccase source for each industrial application is suggested. [ABSTRACT FROM AUTHOR]

Aiming at purification of NO x from hydrogen internal combustion engines (HICEs), the hydrogen selective catalytic reduction (H 2 -SCR) reaction was investigated over a series of Pt/KFI zeolite catalysts. H 2 can readily reduce NO x to N 2 and N 2 O while O 2 inhibited the deNO x efficiency by consuming the reductant H 2. The Pt/KFI zeolite catalysts with Pt loading below 0.1 wt.% are optimized H 2 -SCR catalysts due to its suitable operation temperature window since high Pt loading favors the H 2 -O 2 reaction which lead to the insufficient of reactants. Compared to metal Pt0 species, Ptδ+ species showed lower activation energy of H 2 -SCR reaction and thought to be as reasonable active sites. Further, Eley-Rideal (E-R) reaction mechanism was proposed as evidenced by the reaction orders in kinetic studies. Last, the optimized reactor was designed with hybrid Pt/KFI catalysts with various Pt loading which achieve a high NO x conversion in a wide temperature range. [ABSTRACT FROM AUTHOR]

The challenge of devising pathways for organic synthesis remains a central issue in the field of medicinal chemistry. Over the span of six decades, computer-aided synthesis planning has given rise to a plethora of potent tools for formulating synthetic routes. Nevertheless, a significant expert task still looms: determining the appropriate solvent, catalyst, and reagents when provided with a set of reactants to achieve and optimize the desired product for a specific step in the synthesis process. Typically, chemists identify key functional groups and rings that exert crucial influences at the reaction center, classify reactions into categories, and may assign them names. This research introduces Rxn-INSIGHT, an open-source algorithm based on the bond-electron matrix approach, with the purpose of automating this endeavor. Rxn-INSIGHT not only streamlines the process but also facilitates extensive querying of reaction databases, effectively replicating the thought processes of an organic chemist. The core functions of the algorithm encompass the classification and naming of reactions, extraction of functional groups, rings, and scaffolds from the involved chemical entities. The provision of reaction condition recommendations based on the similarity and prevalence of reactions eventually arises as a side application. The performance of our rule-based model has been rigorously assessed against a carefully curated benchmark dataset, exhibiting an accuracy rate exceeding 90% in reaction classification and surpassing 95% in reaction naming. Notably, it has been discerned that a pivotal factor in selecting analogous reactions lies in the analysis of ring structures participating in the reactions. An examination of ring structures within the USPTO chemical reaction database reveals that with just 35 unique rings, a remarkable 75% of all rings found in nearly 1 million products can be encompassed. Furthermore, Rxn-INSIGHT is proficient in suggesting appropriate choices for solvents, catalysts, and reagents in entirely novel reactions, all within the span of a second, utilizing nothing more than an everyday laptop. [ABSTRACT FROM AUTHOR]

Roasting is an important step in the pretreatment of biomass upgrading. Roasting can improve the fuel quality of biomass, reduce the O/C and H/C ratios in the biomass, and provide the biomass with a fuel quality comparable to that of lignite. Therefore, studying the structure and component evolution laws during biomass roasting treatment is important for the rational and efficient utilization of biomass. When the roasting temperature is 200–300 °C, the cellulose and hemicellulose in the biomass undergo a depolymerization reaction, releasing many monocyclic aromatic hydrocarbons with high reactivity. The proportion of monocyclic aromatic hydrocarbons in biomass roasting products can be effectively regulated by controlling the reaction temperature, residence time, catalyst, baking atmosphere, and other factors in the biomass roasting process. This paper focuses on the dissociation law of organic components in the pretreatment process of biomass roasting. [ABSTRACT FROM AUTHOR]

The catalytic cracking of pyrolysis gasification tar into H2 has garnered significant attention due to its exceptional conversion efficiency. In this study, the effects of pollutant concentration, residence time, weight hourly space velocity (WHSV), and reaction temperature on the hydrogen performance of LaFe0.5Ni0.5O3 perovskite were comprehensively investigated. Results revealed that moderate pollutant concentration (0.3 g/L), low-medium residence time (250 SCCM), and low WHSV (0.24 gtoluene/(gcat·h)) facilitated efficient interaction between LaFe0.5Ni0.5O3 and toluene, thus achieving high hydrogen production. An increase in reaction temperature had minimal effect on the hourly hydrogen production above 700 °C but caused a significant increase in methane production. Additionally, the effects of oxygen evolution reactions, methane reactions, and methane catalytic cracking reactions of perovskite induced by different reaction conditions on tar cracking products were discussed in detail. Compared to previous reports, the biggest advantages of this system were that the hydrogen production per gram of tar was as high as 1.002 L/g, and the highest hydrogen content in gas-phase products reached 93.5%, which can maintain for approximately 6 h. Finally, LaFe0.5Ni0.5O3 showed good thermal stability, long-term stability, and catalyst reactivation potential. [ABSTRACT FROM AUTHOR]

Conductive metal‐organic frameworks (c‐MOFs) have uniform, adjustable pore sizes and customizable functional groups and excellent electrical conductivity, making them promising electrode materials for electrochemical energy storage. However, the synthesis of high crystallinity c‐MOFs remains a significant challenge. The purpose of this review is to provide guidance for the synthesis of high crystallinity c‐MOFs and emphasize their applications in the field of energy storage. We begin with reviewing the influence of various reaction conditions on the morphology, size, and crystallinity of c‐MOFs, and then summarize the current work on c‐MOFs in the field of electrochemical energy storage from both experiment and modeling. Furthermore, the existing issues are discussed in the development of c‐MOFs and the primary directions for future research. [ABSTRACT FROM AUTHOR]

Sulfide‐based all‐solid‐state batteries (ASSBs) have attracted wide attention due to their notable advantages in energy density and enhanced safety. However, whether or not copper (Cu) current collectors can be adopted in sulfide‐based ASSBs remains unclear, as sulfide electrolyte (SE) may react with Cu, causing premature failure of the ASSBs. Herein it is reported that in the presence of traces amount of water, e.g. in a dry room with a dew point of −50 °C, the SE reacts with water to produce H2S, which corrodes Cu to produce Cu2S, causing serious performance degradation to the ASSBs. Conversely, in an anhydrous environment (such as within a glove box), SE is virtually inert to Cu, rendering Cu a valid current collector. This study establishes the conditions that Cu can be used as the current collectors for sulfide‐based ASSBs, which provides important guidance for the industrialization of ASSBs. [ABSTRACT FROM AUTHOR]

This article introduces the actual production situation of a 1.2 MM TPY continuous reforming unit in a certain company, explores the reasons that affect the output of mixed xylene products, and proposes optimization measures. Taking the yield of mixed xylene as the optimization objective, relevant optimization strategies are explored in three stages: feedstock optimization, reaction process and product distillation. The optimization measures are as follows: (1)In terms of feedstock optimization, the aromatics potential content of naphtha resources is ranked, and the aromatics potential content in the reforming feed is controlled at around 45 % ; According to the load capacity of the unit and the situation of feedstocks, the initial boiling point of the reforming feed is increased from 67 °C to 74 °C, and the mass fraction of C8 component in the reaction feed is increased by 1. 8 percentage points, and the production of mixed xylene is increased by about 2 t/h; (2)In terms of the reaction process, the reaction temperature is reduced from 524 °C to 518 °C, which improves the conversion rate of aromatics; Control the chlorine mass fraction between 0. 5 and 0. 7 µg/g ensures the acidic function of the catalyst; (3)In terms of product distillation, with the target product quality as the goal, optimize the temperature of the sensitive plate in the distillation section, optimize the separation strategy for mixed xylene, avoid xylene resources flowing into gasoline, and control the para xylene content in C9+ naphtha to a minimum. Adjustment result: The abnormal decrease in the content of mixed xylene products is avoided, while maximizing production of mixed xylene. [ABSTRACT FROM AUTHOR]

AbstractThe properties of NaGdF4:Yb, Er nanomaterials tuned by synthesis conditions have always been one of the research hotspots in the field of upconversion nanomaterials. In this work, NaGdF4:Yb, Er upconversion nanomaterials capped with oleic acid (OA) molecules were prepared by one-step hydrothermal method. Controlling the fluorescence properties of NaGdF4:Yb, Er nanomaterials by changing the synthesis conditions were principally investigated. The results showed that the crystalline state of the as-prepared upconversion nanomaterials tended to be intact and fluorescence emission capability enhanced when the reaction temperature increased from 140 °C to 160 °C, 180 °C and the reaction time extended from 6 h to 18 h. From 0.00 mmol to 0.75, 2.25, 5.00, 8.75, 12.50, 17.50 mmol of sodium hydroxide amount, the synthesized upconversion nanoparticles (UCNPs) transferred from orthorhombic GdF3 to hexagonal β-NaGdF4. And when the amount of sodium hydroxide was 2.25 mmol, the as-prepared nanoparticles exhibited stronger luminescence intensity. The ratio of Re3+ (Gd3+:Yb3+:Er3+) could also affect the properties of the as-prepared UCNPs. The nanomaterials emitted relatively stronger fluorescence when the ratio among Gd3+, Yb3+, Er3+ was 78:20:2. This work provides solid foundation for further theoretical study and practical application of NaGdF4:Yb, Er nanomaterials. [ABSTRACT FROM AUTHOR]

Greenhouse gases emissions are in the spotlight of global politics and economics. To accomplish carbon neutrality, new ways of producing energy and chemicals are necessary. Bioethanol stands out as an important molecule in this scenario. This work brings abroad vision of the importance of bioethanol and its perspectives, discussing the most recent and relevant catalytic studies for several reactions using it as feedstock. In the end, we outline possible biorefinery arrangements using the discussed routes and most promising catalysts. This article review may shed light to the development of biorefineries, contributing to the growth of green chemistry. [ABSTRACT FROM AUTHOR]

Plastics and plastic products have become part of our lives extremely quickly. Although, they make our lives easier in many aspects, at the end of their useful life, especially thanks to the thoughtless actions of people, they are becoming a serious environmental problem. Even though the laws and legislation are still forcing limits of using the plastic products and thus prevent waste, the concept of plastic-free living is probably not going to be reached easily and quickly. Using the recycling technology, we can prepare the recycled material, which represents a new raw material resource. With the right choice of physical-chemical parameters of recycled materials and using a suitable reaction condition we can incorporate them into the asphalt mixtures. Since their introduction the polymer-modified asphalt mixtures have gained in importance during the second half of the twentieth century, and they now play a fundamental role in the field of road paving. Moreover, the use of recycled plastic in such a product will contribute to the technical and economic recovery of secondary raw materials. The use of various recycled material in paving industry is a common practice but needs further research work. Thus, this study aims to the incorporation of recycled plastics into asphalt mixture. The main objective of our work was to find a suitable recycled plastic, which with its physico-chemical and technical parameters is suitable for incorporation into the asphalt mixture. In our study the recycled low-density polyethylene granulate was used, taken from films and various packaging materials. Our preliminary laboratory experiments were based on the possibilities to prepare and characterized the asphalt mixtures containing recycled plastic at different percentage, i.e., 4 %, 6 %, 8 % and 10 % by weight of bitumen. The experimental tests performed in the study were bitumen content, intergranularity, maximum bulk density, water sensitivity and resistance to permanent deformations. The results showed that the mix containing 6 % by weight of recycled plastic has ideal properties and meets most of the criteria that have been set for asphalt mixes. A commercially available polymer of similar chemical composition to the recycled material was used as a reference sample. [ABSTRACT FROM AUTHOR]

CO2 utilization as resource is an indispensable part to achieve the goal of “carbon peaking and carbon neutrality”. Catalytic conversion of CO2 to formic acid is an effective and most atomic economically viable route. However, due to the stable thermodynamic properties of CO2, it is difficult to be activated and the conversion rate of above reaction is generally low. In order to obtain a higher formic acid yield under mild conditions, photocatalysis is combined with thermal catalysis. Photothermal catalysis is mainly reflected in photoactivation, which effectively activates CO2 by stimulating carrier, regulating electron injection location and adsorption site. Thermal energy could further enhance the adsorption rates of CO2, charge transfer and reaction, and activate the thermally active sites, which could improve the yield and selectivity of formic acid by combining the advantages of low energy consumption of photocatalysis and high efficiency of thermal catalysis. At present, the main challenge of photothermal CO2 reduction to formic acid is the inherent chemical stability of CO2 which results in a low CO2 conversion rate, uncontrollable product and poor selectivity etc. Considering the current demand for the photothermal catalytic CO2 conversion technology, this study introduced the principles, advantages and disadvantages of photocatalysis, thermal catalysis and photothermal catalysis. The strategies for improving CO2 conversion and formic acid selectivity were reviewed from the aspects of catalyst modification, reaction conditions and reactor selection. The modification methods of catalyst were mainly elaborated, including the improvement of electron-hole separation degree, the regulation on the proportion of exposed surface and the improvement on the adsorption of CO2. The key problems of photothermal CO2 reduction to formic acid were described in detail. In future studies, the production of high-yield formic acid and large-scale industrial application of photothermal catalysis can be realized by optimizing the reaction conditions and comprehensively considering the reactor selection and catalyst design.

Inorganic nanoscintillators exhibit a promising innovaion for the detection of tritiated water with highly biotoxicity. In this work, CaF2:Eu2+ nanoparticles were synthesized via hydrothermal method. The effects of reaction conditions on phase composition, microstruture and luminescence properties of nanopowders have been characterized by XRD, SEM and FS. The results show that the obtained nanoparticles are the pure CaF2 phase with cubic structure. The nearly spherical particles are well dispersed with an average size of about 30 nm. CaF2:Eu2+ nanopowders exhibit an emission peak of 425 nm under 339 nm UV excitation, and own the optimal emission intensity at the reaction condition of 180 °C and 24 h. [ABSTRACT FROM AUTHOR]

The growing popularity of silver nanoparticles in the field of nanotechnology has created the necessity of developing new sustainable synthesis methods. This study presents a new green in situ functionalization method of melamine foams with silver nanoparticles. The synthesis pathway and the influence of the processing parameters are optimized to phase out 100% of polluting and dangerous solvents while maximizing silver transfer. A deep study of the morphological and chemical changes of the synthesized silver nanoparticles successfully demonstrated that water can be used as the only solvent for obtaining active melamine foams with potential application in multiple fields. Results showed that rising reaction temperatures from environmental to mild conditions (40 °C and 60 °C) is crucial for obtaining high functionalization yields with this green method. Following the optimum fabrication conditions using only water, highly functionalized melamine foams showed a great amount of ultrafine silver nanoparticles distributed over the porous structure. [ABSTRACT FROM AUTHOR]

The etherification of glycerol with ethanol is a novel process to utilize low-value by-product (glycerol) of the biodiesel industry. Herein, glycerol ethers are utilized as a solvent or fuel additive. Its production will be in stages. In the first stage, bioethanol production has been achieved with a volumetric concentration of 96% from a cheap source, which is dates, especially the type called Zuhdi, which is available in large quantities in Iraq. This ethanol produced in the etherification process is used to produce glycerol diethyl ether. Then, the next step is to determine whether mixing the generated glycerol ether with gasoline will increase its octane rating (Al-Doura Refinery Gasoline in Iraq). In the current study, the ethanol–glycerol to strong acid ion exchange resin (CER) process is carried out, where CER is used as the solid acid for the etherification process. Glycerol ether and ethanol were conducted at 120–150 °C in a batch reactor with and without CER, and the final pressures were observed to be around 14–18 bar. The products from the reaction process were glycerol triethyl ether (GTEE), glycerol diethyl ether (GDEE), diethyl ether (DIEE), and glycerol monoethyl ether (GMEE). The current findings show that when the ratio of ethanol to glycerol in the reaction mixture increased, the amount of glycerol converted to ethanol decreased. Besides, the conversion of the reactants witnessed a slight decrease with increasing pressure. Finally, the excellent component mixtures obtained from the previous results are G-PCM10 due to the recommended increase in RON concentration. G-PCM10 was a prepared pool octane booster. [ABSTRACT FROM AUTHOR]

Straw pyrolysis co-production has been one of the most important ways to realize the efficient utilization of straw at present, particularly for the high high-quality biochar and combustible gas. Much efforts have has been made on the important data support for the development of straw pyrolysis carbonization technology. However, it is still lacking on the straw charcoal return to field utilization for the carbon quality under different pyrolysis conditions, especially the correlation analysis for the various physical and chemical properties of straw charcoal. In this study, a systematic investigation was carried out to clarify the effects of pyrolysis temperature and residence time on the physicochemical properties of rice straw pyrolysis products (mainly the return to field utilization index). The correlation analysis was also performed on the specific surface area of rice straw carbon, electrical conductivity, pH value, and cation exchange capacity. At the same time, the yield and energy distribution of products were explored under different experimental conditions. A simple and practical platform was established for the slow pyrolysis of rice straw and the collection of all components of carbon, gas and liquid products. An analysis was made to determine the influence of pyrolysis temperature (450, 500, 550, 600, and 650 °C) and residence time (30, 40, 50, and 60 min) on the pyrolysis products of rice straw using the slow pyrolysis co-production. The results show that the pyrolysis temperature was posed the an outstanding effect on the product characteristics and yield, while only a little effect was observed in the residence time. When the pyrolysis temperature increased from 450 °C to 650 °C, the carbon yield of rice straw gradually decreased from 40.8% to 35.1%, with a decrease of 5.7 percentage points. The calorific value also decreased slightly. The pyrolysis gas yield increased from 18.3% to 20.7%, with an increase of 2.4 percentage points. The gas calorific value increased from 10.3 to 15.1 MJ/Nm3, with an increase of 4.8 MJ/Nm3, due mainly to the increase in the yield of alkane and olefin olefinenriched gases, such as H2 and CH4. The pyrolysis temperature was reduced the volatiles of rice straw carbon for the high content of fixed carbon. The O/C and H/C of rice straw carbon that produced in the range of 450~650 °C were lower than 0.2, indicating the better stability. There was a strong correlation between the specific surface area, conductivity, and pH value of rice straw carbon. Specifically, the correlation coefficients between the specific surface area and pH value, pH value and conductivity, and the specific surface area and conductivity were 0.83, 0.66, and 0.54, respectively. An increasing trend was found in the specific surface area, conductivity, and pH value of rice straw carbon with the increase of in temperature. The highest specific surface area, the highest electrical conductivity, and the highest pH were 83.4 m2/g, 1 059 μs/cm, and 10.5, respectively. There was no significant change in the cation exchange capacity in the temperature range. The average cation exchange capacity was 56.4 cmol/kg. The energy distribution of rice straw pyrolysis products also changed with the increase of in temperature. The more energy that contained in raw materials was transferred to the gas products. The carbon energy yields of rice straw were 53.8% and 45.2% at the temperatures of 450 °Cand 650 °C, respectively, whereas, the pyrolysis gas energy yields were 11.6% and 19.1%, respectively. The finding can provide the basic data support to the simplified pyrolysis equipment for the rice straw. [ABSTRACT FROM AUTHOR]

In this article, COD, volatile phenol and ammonia nitrogen concentrations of the wastewater from semicarbon are reported as 38,000; 6,400 and 5,700 mg/L, respectively. According to the field test, when the pH of the wastewater is 9, the field test temperature is 20 °C, the adsorption time is 30 min and the optimal dosing ratio of nitrogen-doped gasification slag (HX-NGS) to the wastewater is 1:4, HX-NGS has the best removal effect on COD, volatile phenol and ammonia nitrogen in the wastewater from the semicarbon. The removal rates of COD, volatile phenol and ammonia nitrogen are 94, 91 and 85%, respectively, and the concentrations of the remaining COD, volatile phenol and ammonia nitrogen are 2,280, 576 and 855 mg/L, respectively, after regeneration, the material HX-NGS has a good effect on the treatment of the wastewater from the semicarbon. The reuse rate of the adsorption material is at least eight times. The adsorption effect of the material HX-NGS conforms to the mechanism law of dynamics and thermodynamics. HIGHLIGHTS Physical extraction is adopted without adding chemical agents, which will not lead to secondary pollution of water in the treatment link with no increase in solid and liquid wastes.; Moreover, the extraction materials can be recycled for use, with a strong adsorption capacities for oil and phenol.; The first adsorption can handle about 80% of polyphenol, SS, etc.;

Methanation is the core process of synthetic natural gas, the performance of the entire reaction system depends on precise values of the reaction condition parameters. Accurate predictions of the CO conversion rate of the methanation reaction can eliminate time-consuming and complex steps in experiments and speed up the discovery of the best reaction conditions. However, the methanation reaction is an uncertain, highly complex, and highly nonlinear process. Thus, this paper proposes a machine learning prediction model for the methanation reaction to facilitate the subsequent search for optimal reaction conditions. The reaction temperature, pressure, hydrogen–carbon ratio, water vapor content, CO 2 content, and space velocity were selected as the condition variables. The CO conversion rate was the optimization objective. An extreme learning machine (ELM) was selected as a prediction model. Because the input weights and bias matrices of the ELM are randomly generated, an ELM based on a state transition simulated annealing (STASA-ELM) algorithm is proposed. The STASA algorithm was used to optimize the ELM to improve the accuracy and stability of the model. Five additional sets of experimental data were designed for the experiment, and the error between the experimental and predicted values was small. Thus, the STASA-ELM algorithm can accurately predict the conversion of CO for different values of reaction conditions. [Display omitted] • Methanation reaction conditions were predictively modeled by machine learning. • ELM-STASA optimization improved the stability and accuracy of model prediction. • Very small error was obtained between predicted and experimental results. • Machine learning showed advantages with saving time, labor and material resources. [ABSTRACT FROM AUTHOR]

The reaction of the 1,3-diphosphete complex [Cp'''Co(η4-P 2 C 2 t Bu 2)] with the Ag(I) and Au(I) salts of the weakly coordinating anion Al{OC(CF 3) 3 } 4 results in aggregation processes which can be controlled by the reaction conditions. Accordingly, a variety of mono-, di- and polycationic species could be selectively isolated and characterized. [Display omitted] Reactions of the 1,3-diphosphete complex [Cp'''Co(η4-P 2 C 2 tBu 2)] (Cp''' = Cp(tBu) 3 , 1) with Ag[Al{OC(CF 3) 3 } 4 ] (Ag[TEF]) and [LAu][TEF] (L = (THT) 2 , (THT)PPh 3) were studied under various reaction conditions. Depending on the stoichiometry of the reactants, reaction time and temperature involved, a selective formation of the monomers, [{(Et 2 O)Ag}{Cp'''Co(µ,η4:η1:η1-P 2 C 2 tBu 2)}][TEF] (4) and [Au{Cp'''Co(η4:η1-P 2 C 2 tBu 2)} 2 ][TEF] (6), the dimer [{(Et 2 O)Ag} 2 {Cp'''Co(µ,η4:η1:η1-P 2 C 2 tBu 2)}]·2[TEF] (3), the trimers [Au 3 {Cp'''Co(η4:η1:η1-P 2 C 2 tBu 2)} 4 ]·3[TEF] (7) and [(η1-PPh 3) 2 Au 3 {Cp'''Co(η4:η1:η1-P 2 C 2 tBu 2)} 2 ]·3[TEF] (8), and the one-dimensional polymer [Ag{Cp'''Co(η4:η1:η1-P 2 C 2 tBu 2)}] n [TEF] n (2) was realized. DFT calculations provided additional insight into the formation of the polymeric species during the assembling process of 2 , 3 and 4. All compounds were characterized in the solid state by X-ray crystallography and in solution by multinuclear NMR spectroscopy and mass spectrometry. [ABSTRACT FROM AUTHOR]

To contribute to the reduction of carbon emissions, municipal sludge has to be utilized as a resource instead of being disposed of, especially since current sludge disposal methods encounter problems such as high dehydration energy consumption and secondary pollution. In this study, Fe/Al composite oxygen carriers (FOCs) were prepared using Al 2 O 3 particles as carriers and Fe(NO 3) 3 ·9H 2 O as a precursor. Chemical looping gasification (CLG) of wet municipal sludge was conducted in a FOC-loaded fixed bed reactor, and the effect of reaction parameters and conditions on FOCs and syngas generation characteristics were analyzed by various methods. The results showed that the participation of water vapor in the gasification reaction significantly improved the hydrogen production rate of sludge gasification and avoided the over-reduction of the FOC. The vapor released from sludge significantly improved the thermal conversion efficiency of the sludge. Higher temperatures were conducive to the gasification reaction in the first stage, but when the reaction temperature reached 900 °C, the FOC slightly sintered, the reaction atmosphere was affected, and the hydrogen ratio in syngas started decreasing. Controlling the mixing ratio of FOC to sludge (O/H) was an important influencing factor for preparing high-quality syngas. When O/H was higher than 0.25, the quality of syngas decreased significantly. The conclusions obtained in this study can guide the selection of reaction conditions for the CLG of wet sludge using FOCs to prepare hydrogen-rich syngas. • Steam facilitates the acceleration of the sludge pyrolysis reaction, thereby promoting the CLG reaction. • Sludge self-moisture can enhance the reforming reaction of volatile matter, thereby improving the syngas quality. • As O/H ratio increases, the redox reaction between OC and sludge intensifies, diminishing the syngas quality. [ABSTRACT FROM AUTHOR]

For semiconductor materials TiO2 and Cu2S with different band gaps as photocatalysts, the effects of different light intensity, temperature, pressure reaction conditions, and light-gathering reaction conditions on CO2 reduction rate were studied. The results show that the photocatalysis efficiency of the materials change obviously before and after changing the reaction conditions. The reduction rate of CO2 could be effectively improved by light-gathering reaction. Through XRD analysis and SEM analysis, the efficiency improvement is not due to the formation of new substances and the change of crystals. The optimal reaction conditions can greatly improve the photocatalytic performance. [ABSTRACT FROM AUTHOR]

Polyester is favored by people because of its excellent properties such as high strength excellent stretch resistance and good wear resistance. However due to the high degree of orientation of polyester and the lack of active groups polyester exhibits some drawbacks influencing its wearing comforts such as poor hydrophobicity and problems in dying which also limits its application as a high-end material in the fields of medical treatment food packaging and electronic devices. To improve the hydrophilic property of polyester technologies such as alkali reduction treatment finishing agent coating and enzymatic hydrolysis are used in the modification of polyester fabrics. From the point of view of economy and ecology the enzyme-catalyzed reaction is carried out under mild reaction conditions without causing pollution which can maintain the excellent mechanical properties of polyester. Therefore enzyme-catalyzed polyester modification has broad prospects. Compared with lipase cutinase lacks lid structure and the active site is directly exposed to the solvent. This open and shallow active site allows better contact between the catalytic center and the substrate and has better modification ability. Compared with chemical modification there are still some shortcomings such as long reaction time and unsatisfactory catalysis effect in the reports on cutinase modification on the polyester. Therefore improving the modification effect and shortening the treatment time are a new direction of current research. To improve the hydrophilicity of polyester mutant T. fusca cutinase with excellent thermal stability was used to hydrolyze the surface of polyester and the single factor variable test was applied to determine the suitable process conditions for enzymatic treatment of polyester a cutinase dosage of 20 U/ g a reaction time of 48 h a treatment temperature of 60 ℃ and a pH value of 8. Furthermore the effects of Ca2+ volume concentration on the yield of TPA in the hydrolyzate were also studied. The result showed that the addition of Ca2+ can increase the yield of TPA by 53% compared with the single enzyme treatment which strengthened the hydrolysis effect of the enzyme on polyester. Moreover SEM showed that the fibers treated with cutinase had an obvious etching surface. At the same time the surface wettability of the cutinase-treated fiber was also improved. The surface contact angle value of polyester changed from being hydrophobic to being hydrophilic. The dyeing effect of the fabric was improved and the absorbance of the methylene blue dye solution decreased by 43% indicating that the ester bond of polyester was hydrolyzed to generate hydrophilic groups. This is consistent with the results detected by HPLC with the main hydrolysis product being TPA. Enzymatic modification has been widely used in textiles. However due to the dense structure and high crystallinity of polyester the catalytic effect of cutinase still needs to be further improved. The following measures can be taken to improve the effect of enzymatic modification of polyester. Firstly it is recommended to develop new additives that can maintain the thermostable properties of enzymes to improve the tolerance of enzymes to reaction conditions. Secondly it is suggested to use the synergistic effect of the multi-enzyme system to reduce the inhibition of BHET on enzymes and improve the hydrophilicity of polyester. Finally it is proposed that the polyester should be pretreated to increase its specific surface area improve the accessibility between enzymes and substrates and reduce the catalytic reaction time. [ABSTRACT FROM AUTHOR]

Electrochemical processes offer defossilized alternatives to conventional routes. Key processes, such as hydrogen evolution and electrochemical CO 2 reduction, are typically paired with the anodic oxygen evolution reaction (OER). However, the generated oxygen holds little value and the electrical costs associated with energy-intensive OER pose a significant economic barrier. The methanol oxidation reaction (MOR) to formate is a promising alternative to OER, requiring less energy and providing a value-added product. Extensive research focuses on MOR regarding high Faraday efficiencies, but conversion and product yields are mostly neglected. However, high conversion with sufficient yield is a prerequisite to transition from lab-scale catalysis towards feasible industrial applications. In this work, we investigated the selectivity of MOR to formate with progressing conversion at high current densities of up to 200 mA/cm 2 on hierarchically structured copper(II) oxide electrodes. We assessed the impact of the reaction conditions, including current density, temperature, flow rate, electrolyte composition, and membrane type. We found a positive influence of low current density and high temperature on the FE. Through tailored reaction conditions, we achieved a formate yield of 70% at 100 mA/cm 2 with an anodic potential of 1.33 V vs. RHE. The anodic potential remained below typical OER potentials even at high conversion. For the first time, we demonstrated that MOR can achieve significant formate yields at high current density. Our results reveal the impact of conversion, reaction conditions and ion balance on selectivity and provide valuable insights for operating MOR at high yield in paired processes, e.g., with hydrogen evolution or CO 2 reduction. [Display omitted] • Hierarchical electrode with CuO dendrites on copper foam provides a high surface area. • FE to formate up to 93% at 200 mA/cm 2 depending on reaction conditions. • High initial FE, but FE decreases drastically with increasing methanol conversion. • At 100 mA/cm 2 and 55 °C, initial FE near 100%, final yield of 70% at 90% conversion. • Water and ion balance influence the suitable choice of a paired electrolysis setup. [ABSTRACT FROM AUTHOR]

Natural polysaccharides are attractive and promising biomacromolecules for the green synthesis of silver nanoparticles (Ag NPs) with a broad spectrum of useful functions. This study aims to evaluate the synthetic conditions and physical properties of Ag NPs using three fractions of exopolysaccharide (EPS), namely EPS-1, EPS-2, and EPS-3, produced by a medicinal fungus known as Cs-HK1, with variations in their chemical composition and molecular weight. Each of the EPS fractions had a unique set of optimal synthetic conditions (reaction time course, temperature, and reagent concentration), resulting in a specific range of Ag NP size distributions. The Ag NPs synthesized with the EPS-1 fraction had the smallest particle size (~160 nm) and the most significant antibacterial activities against Escherichia coli (Gram−) and Staphylococcus aureus (Gram+), with a minimal inhibitory concentration (MIC) of 0.2 mg/mL on E. coli and 0.075 mg/mL on S. aureus. The results proved the success of the scheme of this green synthesis scheme with all three EPS fractions and the potential antibacterial application of EPS-coated Ag NPs. [ABSTRACT FROM AUTHOR]

Similar to the metal centers in biocatalysis and homogeneous catalysis, the metal species in single atom catalysts (SACs) are charged, atomically dispersed and stabilized by support and substrate. The reaction condition dependent catalytic performance of SACs has long been realized, but seldom investigated before. We investigated CO oxidation pathways over SACs in reaction conditions using atomically dispersed Au on h-BN (AuBN) as a model with extensive first-principles-based calculations. We demonstrated that the adsorption of reactants, namely CO, O2 and CO2, and their coadsorption with reaction species on AuBN would be condition dependent, leading to various reaction species with different reactivity and impact the CO conversion. Specifically, the revised Langmuir–Hinshelwood pathway with the CO-mediated activation of O2 and dissociation of cyclic peroxide intermediate followed by the Eley–Rideal type reduction is dominant at high temperatures, while the coadsorbed CO-mediated dissociation of peroxide intermediate becomes plausible at low temperatures and high CO partial pressures. Carbonate species would also form in existence of CO2, react with coadsorbed CO and benefit the conversion. The findings highlight the origin of the condition-dependent CO oxidation performance of SACs in detailed conditions and may help to rationalize the current understanding of the superior catalytic performance of SACs. [ABSTRACT FROM AUTHOR]

Copyright of Journal of China University of Petroleum is the property of China University of Petroleum 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.)

Hydrocracking of solvent deasphalted (SDA) pitch was performed in batch and semi-batch systems, at different reaction temperatures (380–430 °C) with varying amounts of Mo-octoate precursor (0–1,000 ppm Mo) under 70–130 bar of H2 pressure. The reusability of the catalyst was also examined. Coke formation was unavoidable in the hydrocracking of the asphaltene-rich feed. The coke induction period was prolonged when the catalyst was introduced. Increasing the Mo catalyst concentration decreased the coke yield and improved the product quality. The catalytic hydrocracking of the SDA pitch under high H2 pressure suppressed coke formation, promoted desulfurization, and increased the H/C ratio of the liquid products. At least 500 ppm of Mo catalyst and H2 pressur above 110 bar were required for the hydrocracking of SDA pitch with controllable coke generation in the semi-batch system. Sufficient hydrogen supply and moderate catalyst concentration were essential for the slurry-phase hydrocracking of asphaltenerich feedstocks to enhance the product quality and suppress coke formation. [ABSTRACT FROM AUTHOR]

In this paper, ozone oxidation was used to treat refinery alkaline residue, the effect of reaction conditions on ozone treatment of refinery alkali residue was explored by single factor experiment and orthogonal experiment method, and the influence of ozone oxidation on the products and biodegradability of refinery alkali residue was investigated. The results showed that the reaction temperature and time were the main factors affecting the ozone treatment of alkali residue, while the amount of ozone was the secondary factor, and the optimal condition of ozone oxidation of refinery alkali residue was that the reaction temperature, the amount of ozone, and the reaction time were 50 °C, 150 L/h, and 75 min, respectively. Under these conditions, the COD removal rate of refinery alkali residue was about 50%. Ozone can transform and degrade macromolecular organic matter in refinery alkali residue illustrated in GC-MS total ion chromatogram (TIC) to reduce the toxicity of refinery alkali residue. The COD removal rate of ozone-oxidized refinery alkali residue treated by activated sludge can be increased by 1.7 times, indicating that ozone oxidation can obviously improve the biodegradability of refinery alkali residue. In conclusion, ozonation can be used as pretreatment technology of refinery alkali residue before entering biochemical treatment system in refinery. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystals (CNCs) are crystalline nano-rods that have high specific strength with hydroxyl surface chemistry. A wide range of chemical modifications have been performed on the surface of CNCs to increase their potential to be used in applications where compatibilization with other materials is required. Understanding the surface chemistry of CNCs and critically examining the functionalization technique are crucial to enable control over the extent of modification and the properties of CNCs. This work aims to optimize the surface modification of wood-derived CNCs with isocyanatoethyl methacrylate (IEM), a bifunctional molecule carrying both isocyanate and vinyl functional groups. We studied the effect of modification reaction time and temperature on the degree of substitution, crystallinity, and morphology of the CNCs. We found that the degree of modification is a strong and increasing function of reaction temperature over the range studied. However, the highest temperature (65 °C) and the longest time of reaction (6 h) resulted in shorter, thinner, and less crystalline CNCs. We obtained surface hydroxyl conversion of 60.1 ± 6% and percent crystallinity of 84% by keeping the reaction shorter (30 min) at 65 ºC. Also, the copolymerization ability of modified CNCs was verified by polymerizing attached IEM groups with acrylic monomers via solution polymerization. The polymer-grafted CNCs (6% w/w) dispersed better in an acrylic polymer matrix compared to unmodified CNCs (umCNCs), resulting in approximately 100% improvement in the tensile strength and about 53% enhancement in the hardness of the acrylic, whereas addition of 6% w/w umCNCs did not influence the strength and hardness. [ABSTRACT FROM AUTHOR]

[Display omitted] The synthesis of the desired chemical compound is the main task of synthetic organic chemistry. The predictions of reaction conditions and some important quantitative characteristics of chemical reactions as yield and reaction rate can substantially help in the development of optimal synthetic routes and assessment of synthesis cost. Theoretical assessment of these parameters can be performed with the help of modern machine-learning approaches, which use available experimental data to develop predictive models called quantitative or qualitative structure–reactivity relationship (QSRR) modelling. In the article, we review the state-of-the-art in the QSRR area and give our opinion on emerging trends in this field. [ABSTRACT FROM AUTHOR]

Superplasticizers (SPs) are an indispensable ingredient to prepare high performance concrete. In the present work, sodium sulfanilate (ASAA), bisphenol A (B) and formaldehyde (F) were used as the reactive monomers, the sustainable aminosulfonate-bisphenol A-formaldehyde (ASBF) SP was synthesized. The functional groups, the weight-average molecular weight (Mw), the number-average molecular weight (Mn), the sulfonation degree (SD), the dispersion properties of ASBF SP were examined. The relationships between the reaction conditions and the molecular structures, the dispersing behaviors of ASBF SP were built. The optimum reaction conditions of ASBF SP are that the molar ratios of B/ASAA, F/(ASAA + B) are 0.625, 1.2, pH value, reaction temperature and reaction time were kept at 10.8, 90–95 °C, 4 h. The molecule of ASBF SP prepared under the optimum reaction conditions has -NH2, -OH, -C6H5, -SO3 groups and Mw, Mn, PDI, SD for 24,716 Da, 16,855 Da, 1.466, 2.257 mmol/g. The adsorption of ASBF SP provides an electrostatic repulsion force to disperse cement particle. -SO3 group on the molecule of ASBF SP takes place complex reaction with calcium ion on cement. The combined affects cause that ASBF SP has the better dispersing capacity for cement particle and dispersing retention in cement slurry. [ABSTRACT FROM AUTHOR]

Ni/ZSM-5 catalysts were prepared by uniformly loading the active metal Ni to ZSM-5 zeolite using excessive wet impregnation method, and the characterization tests of XRD, SEM, H 2 -TPR, and NH 3 -TPD were carried out. For the prepared Ni/ZSM-5 catalyst, the pyrolysis–catalytic reforming of waste plastics for gas production performance was explored under different reaction temperatures, steam-carbon (S/C) ratio, catalyst addition amount, and plastic type. The results showed that the gas production volume and gas quality of pure pyrolysis of HDPE and catalytic pyrolysis of Ni/ZSM-5 were improved with the increase of temperature. Given the thermal economy, the optimal pyrolysis temperature was 700 °C, the catalytic gas production was 900 mL, and the hydrogen concentration was 64.4 %. S/C ratio of 1.5 and plastic: catalyst of 1 was the best reaction condition, under which the gas production was 1020 mL and the hydrogen concentration was 65.1 %, respectively. In addition, an appropriate increase in the amount of steam and the addition of catalysts would greatly optimize the final gas production performance. However, excess steam and catalysts was unfavorable to the gas production of plastic pyrolysis, resulting in a waste of resources. Finally, as for the gas production of four plastics, LDPE had the best pyrolysis gasification effect with gas yield of 1040 mL and hydrogen concentration of 65.7 %. The order of catalytic pyrolysis effect of different plastics was LDPE > HDPE > PP > PS. • The excellent catalytic properties of Ni/ZSM-5 were verified by its morphology and chemical structure. • The optimal pyrolysis conditions of waste plastics were obtained by regulating the reaction parameters. • The mechanism of the pyrolysis–catalytic reforming of waste plastics was proposed. [ABSTRACT FROM AUTHOR]

Post-synthetically lead treated terbium cation doped zinc sulfide [Zn(Tb)S], Zn(Tb)S/Pb, nanoparticles (NPs) benefit from presence of two sensitizing components, namely ZnS and Pb2+. This work systematically investigates the effects of fine tuning the (a) relative reactant concentration, (b) pH, and (c) temperature of the NP's aqueous dispersion, in order to enhance the Tb3+ emission. All these factors are found to be contributing towards enhancing the Tb3+ emission. A comparison between the Zn(Tb)S/Pb NPs with particle diameters (d) of 3.0 ± 0.5 nm and 2.1 ± 0.2 nm reveal a quantum confinement for the ZnS NPs sensitized component, while the same is not evident for the Pb2+ sensitized counterpart. A simple comparison between the Tb3+ emission in the Zn(Tb)S [d = 3.0 ± 0.5 nm] and Zn(Tb)S/Pb [d = 2.1 ± 0.2 nm] reveals an ∼50 times increase, thus placing this as an important strategy to enhance Tb3+ emission in these NPs for potential luminescence based applications in aqueous medium. [Display omitted] • Reactant amount, pH, temperature enhance Tb3+ emission in the Zn(Tb)S/Pb NPs. • Quantum confinement effect is observed for the ZnS sensitized Tb3+ emission. • Quantum confinement effect is not prominent for the Pb2+ sensitized Tb3+ emission. • An ∼50 times Tb3+ emission is noticed compared to that in the larger Zn(Tb)S NPs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Comprehensive OCM reactor performance analysis was conducted and reported. • Impacts of four operating parameters on the OCM reactor performance were analyzed. • Results of a comprehensive experimentation for 630 sets of conditions were reported. • Novel visualization approach enabled tracking the interactive impacts of parameters. Performance of Oxidative Coupling of Methane (OCM) reactor using the research benchmark Mn-Na 2 WO 4 /SiO 2 catalyst under various sets of operating conditions was experimentally investigated. In particular, the impacts of varying the operating parameters (630 combination-sets) namely; reactor set-temperature (in 6 levels in the range of 750–875 °C), feed flow-rate (in 5 levels in the range representing GHSV -Gas Hourly Space Velocity- of 9600-19200 cm3 g−1 h−1), methane-to-oxygen ratio (CH 4 /O 2 in 7 levels in the range of 1.5–10), and inert gas dilution (in 3 levels at 0%, 25% and 50%) on the recorded trends of methane-conversion and selectivity and yield of the desired products (C 2 : C 2 H 4 &C 2 H 6) were systematically reviewed. The performed experimental analysis enabled determining the impact of each investigated parameter as well as their interactive impacts through a carefully designed set of experiments. The novel proposed contour graphs visualized how the temperature and methane-to-oxygen ratio for instance directly influence the contribution of the catalyst or indirectly affect the reactor performance in synergy with the variation of dilution and feed flow due to their thermal impacts via affecting the intensity of the gas-phase and catalytic reactions in reactor-scale. It was demonstrated that in wide ranges of variation of these operating parameters, the recorded OCM reactor performance for instance in terms of the observed selectivity represent the interactive impacts of the intrinsic characters of the catalyst and the reactor's characteristics such as its dimension and thermal capacity. Therefore, these aspects should be carefully considered in design of experiments and in the interpretation of the experimental observations for the research purposes as well as in the design and operation of large-scale reactors. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Petrochemical Universities / Shiyou Huagong Gaodeng Xuexiao Xuebao is the property of Journal Editorial Department Of Liaoning Shihua 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.)

Copyright of Chinese Journal of Preventive Veterinary Medicine / Zhongguo Yufang Shouyi Xuebao is the property of Chinese Journal of Preventive Veterinary Medicine Editorial Office 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.)

Summary: In the process of one‐step synthesis of methylal via methanol oxidation, the design and research of various dual‐function catalysts are important and studies on the influence of reaction conditions on this type of process are scarce. We explored the influence of reaction temperature, reaction space velocity, and the feed ratio of methanol to air on the catalytic effect of the process based on the Fe‐Mo‐based bifunction catalyst and discovered the most appropriate reaction conditions for the process. Results showed that excessively high reaction temperatures were not conducive to the formation of target product Dimethoxymethane (DMM) and this was verified from the perspective of thermodynamic analysis. At the same time, through Brunaure Emmett Teller (BET), X‐ray diffraction, scanning electron microscope, NH3‐temperature‐programmed chemisorption, and Pyridine Fourier Infrared (PY‐FTIR) characterization, analysis of the microstructure and surface characteristics of the catalyst showed that an excessively high reaction temperature caused accumulation of metal oxides on the catalyst surface to block pores and reduce the specific surface area. This also destroyed the active acidic sites on the catalyst surface and weakened the acidity of the catalyst, thereby reducing catalytic activity. Investigation showed that excessively high reaction space velocity caused most of the formaldehyde obtained by catalyzing the initial oxidative dehydrogenation to fail to undergo polycondensation with methanol after desorption in time to obtain DMM, leading to a significant decrease in DMM selectivity. Investigation of the methanol‐air feed ratio showed that when CH3OH:air = 1.5, the methylal selectivity was highest and catalytic activity had improved. Orthogonal experiments showed that optimal reaction conditions of the process were 663 K, 15 000 h−1 and CH3OH: air = 0.82. In addition, compared with other bifunctional catalysts of this process, the self‐made Mo:Fe(2)/HZSM‐5 bifunctional catalyst exhibited high stability and carbon deposition resistance under severe operating conditions. [ABSTRACT FROM AUTHOR]