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Diverse methods have been developed for the synthesis of active nanocatalysts involving various heterogeneous catalytic reactions. Thus far, numerous trial-and-error runs have been done to find the effective and practical ways. In the present work, the All-In-One (AIO) reactor system with a well-designed synthesis program, now in pilot stage, was first exploited as a reliable synthesis tool to find the optimum conditions for the production of Ni nanocatalysts. Using an activated charcoal support, active Ni nanoparticles of 7.8–11.8 nm (labeled A001–A007 in the program) were produced. These were achieved using a melt-impregnation process, which was controlled by variations in the applied gas (N2 and H2) and temperature (400 °C, 450 °C, and 500 °C) used as critical factors in the calcination step. Based on the optimization of the reaction sequence, each Ni nanocatalyst could be prepared within 5 h and 22 min. In particular, the optimum Ni nanocatalyst (A006) with the smallest particle size (7.8 nm), prepared under H2 flow at 400 °C, exhibits the highest catalytic activity (0.748 mmol4-NP·gcat-1·s-1) among the Ni catalysts for 4-nitrophenol (4-NP) reduction to 4-aminophenol (4-AP). This activity is much higher than that of conventional supported Ni nanocatalysts (0.551 mmol4-NP·gcat-1·s-1) produced using the wetness method.

A water-permeable membrane reactor is proposed to promote CO2 methanation with in situ removal of H2O. A two-dimensional CFD simulation model is built up and the effects of GHSV, H2O permeance and CO2/H2 permeation selectivity are investigated.

Although research on microbubbles (MBs) has intrigued a lot of researchers, very few studies have been done about the influences of MBs on the free radical formation and also on the degradation rates of organic compounds by ultrasonic irradiation. Here we report the degradation of Acid Orange 7 by the ultrasound irradiation in the solution of MBs for the first time. It was found that acceleration of the degradation rate of Acid Orange 7 was observed only for the 45 kHz ultrasonic irradiation to the microbubble solution. Dependence of gases inside the MBs on the sonochemical efficiencies with the existence of MBs was also measured using the KI method and it was found that the dependence of the sonochemical efficiencies on gases inside the MBs was in the order of Kr > Ar ~ N2 > O2 > He, supporting the conclusions that the observed phenomena were due to the cavitation by the 45 kHz ultrasonic irradiation. The dependences of ultrasonic frequency and power were investigated using various commercially available ultrasonic oscillators, and the influence of the size distribution of microbubbles on the sonochemical efficiencies was further investigated using a flow reactor system with two ultrasound generators. Finally, we showed that the frequency of the ultrasound was more sensitive than the size of microbubbles for the sonochemical enhancement by the 45 kHz ultrasonic irradiation to the solution of MBs and then discussed possible roles of nanobubbles in the presently observed phenomena.

Pretreatment on lignocellulosic biomass prior to extraction of biomaterials, degradation of bioproduct, or production of biomaterial/bioproduct/biofuel, crucially influences the intended outcomes. The pretreatment of oil palm fronds (OPF), one of the most abundant agriculture residues in Malaysia, can be conducted based on the need of the methodology, either for small, lab, pilot, or industrial scales. In this article, examples of reactors for the pretreatment for instance microreactor (Bioshake iQ), conical shake flask, and mini-cylindrical reactor scale (fabricated) as well as the monitoring bioreactor (BlueSens Monitoring GmbH) reactor system dedicated for fermentation process using the outcome material from pretreatment process, are presented. All pretreatment trials with ionic liquid (IL) of 1-ethyl-3-methylimidazolium acetate [EMIM]Ac on OPF were conducted with a scaling-up strategy from micro-to-macro to fabricated reactors, monitoring Crystallinity Index (CrI) and Lateral Order Index (LOI). Electron beam irradiation pretreatment using 1000kGy was also tested in macroscale mode for CrI and LOI. Effectiveness of approximately 23 to 37% of CrI via microreactor experiments using 50, 70, and 90% v/v of [EMIM]Ac and at a temperature of 99oC was observed. Higher concentration of IL and temperature with nearly insignificance of solid loading of OPF in reaction liquid to the increase of the amorphous level of OPF was reported by macroscale mode in the 570-mL fabricated reactor. A short oxygen uptake rate (OUR) phase was observed in a 500-mL BlueSens shake flask with the real-time monitoring systems for 45-mL working volume, a nearly 10% of the total reactor volume for saccharification-fermentation using Escherichia coli K011 ATCC 55124 on approximately 2.22% w/v pretreated OPF from macroscale mode. Various data examples from these micro-to-macro scales including in a fabricated reactor system mode are crucially needed for further observations prior to pilot or industrial scales, needing a systematic data collection to be simulated and investigated in the future.

In large-scale bioprocesses microbes are exposed to heterogeneous substrate availability reducing the overall process performance. A series of deletion strains was constructed from E. coli MG1655 aiming for a robust phenotype in heterogeneous fermentations with transient starvation. Deletion targets were hand-picked based on a list of genes derived from previous large-scale simulation runs. Each gene deletion was conducted on the premise of strict neutrality towards growth parameters in glucose minimal medium. The final strain of the series, named E. coli RM214, was cultivated continuously in an STR-PFR (stirred tank reactor – plug flow reactor) scale-down reactor. The scale-down reactor system simulated repeated passages through a glucose starvation zone. When exposed to nutrient gradients, E. coli RM214 had a significantly lower maintenance coefficient than E. coli MG1655 (Δms = 0.038 gGlucose/gCDW/h, p

This work aimed to study the fractionation of sugarcane bagasse using a two-step hydrothermal and ethanosolv process in a flow-through reactor system. The effects of reaction temperature with or wi...

Materials have been selected for the shim rods and burnable absorbers to compensate for the excessive reactivity of the facility’s blanket part and to provide for the possibility of reactivity control in conjunction with a plasma source of neutrons. Burnable absorber is a layer of zirconium diboride (ZrB2) with a thickness of 100 μm applied to the surface of fuel compacts. Boron carbide (B4C) rods installed in the helium flow channels and used to bring the entire system into a state with keff = 0.95 have been selected as the shim rod material. Throughout its operating cycle, the facility is subcritical and is controlled using the neutron flux from the plasma source. Verified codes, WIMS-D5B (ENDF/B-VII.0) and MCU5TPU (MCUDВ50), as well as a modern system of constants were used for the calculations. The facility’s neutronic performance was simulated with regard for the changes in the inner structure and temperature of the microencapsulated fuel and fuel compact materials caused by long-term irradiation and by the migration of fission fragments and gaseous chemical compounds.

In a rapidly changing environment, such as the current COVID-19 pandemic, continuous flow reactors bear the potential to increase the production of urgently needed active pharmaceutical ingredients (APIs) on demand In the synthesis of remdesivir, the organometallic C-glycosylation step was identified as a limitation for the large-scale production, requiring long addition periods and cryogenic temperatures Previous studies have focused on a Grignard-based protocol, but a flash chemistry approach, using organolithium reagents, has facilitated significant improvements After gaining further understanding of the C-glycosylation, this step was successfully transferred to a five-stream continuous flow process, achieving 60% yield at a moderate temperature (−30 °C) in a total residence time of just 8 s Stable processing was demonstrated for 2 h, providing an exceptionally high space−time yield of 10 4 kg L−1 h−1, in a scalable flow reactor system © XXXX American Chemical Society

The existing method for selecting the structure of a power plant for thermally recycling municipal solid waste (MSW) in the Russian Federation does not address the matter of selecting all components of an energy complex operating on MSW, but places focus on determining the best accessible waste thermal neutralization technology. This generates the need to search for new methods and to select criteria of choosing the structure for each particular project. A comparative analysis of various structural schemes of waste-to-energy plants widely used outside of Russia will make it possible to reveal their main advantages and drawbacks, and to determine their application fields. The article describes the statistical indicators characterizing the operation of the flue gas purification system from acid gases, which can be applied in performing a feasibility study, intellectual property assessment, and in carrying out front-end engineering. For waste-to-energy plants constructed in an urban environment and aimed to operate with keeping to a minimum the gross emissions of acid gases into the atmospheric air, the use of a wet reactor system is recommended, which will ensure low emissions of HF, HCl, and SOx. The system with a wet reactor will make it possible to reduce gross emissions of harmful substances during the operation of large capacity waste-to-energy power plants and will be a justified choice in such case. In constructing medium capacity waste-to-energy plants (with a throughput of up to 350 000 t of MSW per annum), semi-dry and dry reactors can be used; for such plants, the technology involving the use of a semi-dry reactor is the most preferred one.

This study aims to develop a two-stage fluidized catalytic bed reactor system for continuous co-production of carbon nanotubes (CNTs) and hydrogen from waste plastics gasification. Ni/Al-SBA-15 and Ni–Cu/CaO–SiO2 catalysts have been synthesized and granulated for CNTs synthesis and hydrogen production in the first- and second-stage reactor, respectively. The operating parameters, including reaction temperature and equivalence ratio (ER), were investigated to confirm the feasibility for CNTs and hydrogen production of this system. The Ni/Al-SBA-15 added in the first-stage reactor enhanced the waste plastics degradation to produce CH4 and C2–C5 hydrocarbons with increasing temperature, which could be used as the source for CNTs synthesis. Lowering the ER promoted the catalytic thermal cracking and reforming of hydrocarbons that contributed to the CNTs and hydrogen production. Nevertheless, the H2 production rate showed a significant increase to 857.6 mmol/h-g catalyst with the assistance of Ni–Cu/CaO–SiO2 in the second-stage reactor. The produced smaller-molecule hydrocarbons from the second-stage reactor with higher temperatures could benefit the co-production of CNTs and hydrogen. The two-stage fluidized catalytic bed gasification system exhibited an optimal performance of high fraction CNTs and H2 when temperatures of first- and second-stage reactor were controlled at 600 and 800 °C, respectively, with 0.1 ER.

In this work, a CaO/CeO2 composite was used in a process that coupled the calcium looping for CO2 capture and CaO/H2O thermochemical heat storage. A four fixed-bed reactor system was used to invest...

Gold nanoparticle (AuNP) formation by applying pulsed discharge plasma in the slug flow reactor system was demonstrated. Experiments were carried out continuously at room temperature. The argon gas as a gas phase and the hydrogen tetrachloroaurate(III) tetra hydrate solution containing lysine as a liquid phase simultaneously flowed in the slug flow reactor system. The flow rates of the feed solution and argon gas were kept at 1.5 and 0.2 mL/min, respectively. To generate discharge plasma, the AC power supply with a bipolar pulsed output at 10 kV was applied. The purple color solution product was obtained, and the ultraviolet–visible (UV–vis) spectrophotometer showed that this possessed the absorption light from 510 to 550 nm associated with the existence of gold nanoparticles in each collected sample. Transmission electron microscopy (TEM) revealed that the lysine-capped AuNPs were produced in a spherical morphology and dispersed in aqueous solution products with a diameter of less than 20 nm.

OAbstract. One of the approaches that has been done to produce a better performance of an intermediate temperature solid oxide fuel cell (IT-SOFC) is by varying the synthesis methods. This paper focused on the proton conducting electrolyte in particularly barium cerate and barium zirconate system namely BaCe0.9Y0.1O3-δ (BCY) and BaZr0.9Y0.1O3-δ (BZY). Supercritical ethanol processing technique is one of the alternative synthesis routes that able to produce ceramics powder at lower calcination temperature. The samples were synthesized in High-Pressure-High-Temperature (HP-HT) Batch Wise reactor system using ethanol as reaction medium. XRD was used to study the structure of both samples and all the data were refined using Rietveld refinement method by X’pert Highscore software. VESTA software is used to observe the crystal structure for both BCY and BZY samples. Both BCY and BZY have 98.16% and 96.55% purity after being calcined at 700°C and 1100°C, respectively. This study showed that BCY has orthorhombic structure with lattice parameter a=8.76Å, b=6.24Å and c=6.21Å and BZY exhibited cubic structure with a=b=c, and a=4.194Å. It was observed that BCY synthesized by supercritical fluid (SCF) method at reduced calcination temperature exhibited an acceptable value of lattice paramter as compared to other method that used higher processing temperature.

Background:Tropane Alkaloids (TAs) are important drugs for curing many diseases in the medical industry.Methods:To sustainably exploit TA resources in endangered traditional Tibetan herbs, the hairy root (HR) systems of Przewalskia tangutica Maxim. and Anisodus tanguticus Maxim. were compared under the same culture conditions.Results:The results indicated that both the Agrobacterium rhizogenes strains and explants affected the HR induction frequency, MSU440, A4 and LBA9402 strains could induce hairy roots following infection of cotyledon and hypocotyl of A. tanguticus while LBA9402 could not induce HR on either explants of P. tangutica. The efficiency of LBA9402 was higher than A4 and MSU440 on A. tanguticus and A4 was better strain than MSU440 on P. tangutica. The hypocotyl explant was more suitable for P.tangutica and cotyledon explant was better for A.tangutica with a transformation frequency of 33.3% (P. tangutica) and 82.5% (A. tanguticus), respectively. In a flask reactor system, both the growth curves of HR for two species both appeared to be “S” curve; however, the HR of P. tangutica grew more rapidly than that of A. tanguticus, and the latter accumulated more biomass than the former. As the culture volume increased, the HR proliferation coefficient of both the species increased. HPLC analysis results showed that the content of TAs in the HR of P. tangutica was 257.24mg/100g·DW, which was more than that of A. tanguticus HR (251.08mg/100g·DW), and the anisodamine in the Pt- HR was significantly higher than that in At-HR. Moreover, tropane alkaloids in the HR of the two species were all significantly higher than that of the roots of aseptic seedlings.Conclusion:Our results suggest that HR of P. tangutica and A. tanguticus both could provide a useful platform for sustainable utilization of two Tibetan medicinal plants in the Qinghai-Tibetan Plateau in the future.

A custom bench-scale continuous-flow catalytic fast-pyrolysis (CFP) reactor system was implemented for the optimization of ex situ CFP and screening of catalysts to gain insight into commercial sca...

The kinetics of the synthesis of noncommercially available quantum dot (QD) solvent N-oleoylmorpholine (NOM) was investigated in a semibatch reactor system to enable scale up. Morpholine was inject...

A microchannel electrochemical reactor system was designed to facilitate the reduction of CO2 to CO, which is composed of a premixing section in the upstream consisting of a circular microchannel f...

Investigation of the viability of the erbium oxide‐based solar thermochemical CO2 splitting cycle is reported. This study aimed to explore the effect of partial thermal reduction (TR) of Er2O3 on the thermodynamic process parameters desirable to design a solar reactor system for the erbium oxide‐based CO2 splitting (ErO‐CS) cycle. First, the percentage TR of Er2O3 is estimated as a function of the TR temperature (TH). Acquired results indicated that to achieve a percentage TR of Er2O3 in the range of 5–100%; the solar reactor has to be functioned in the temperature range of TH = 2327–2677 K. The solar energy required to drive the ErO‐CS cycle (Qsolar-cycle-ErO-CS) was observed to be on the higher side due to the obligation of the elevated values of TH. This rise in the Qsolar-cycle-ErO-CS as a function of percentage TR of Er2O3 reflected in a decrease in the solar‐to‐fuel energy conversion efficiency (ηsolar-to-fuel-ErO-CS). The maximum ηsolar-to-fuel-ErO-CS = 4.04% is achieved for a percentage TR of Er2O3 = 25% (TH = 2432 K). By employing 100% heat recuperation, the ηsolar-to-fuel-ErO-CS (for percentage TR of Er2O3 = 25%) increased up to 5.79%. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd.

Food waste (FW) management has become an important issue worldwide. Diverting FW into the sewer system is considered promising to tackle the FW issue. However, the transformation of FW in sewers and its impact on the sewer process have not received adequate attention due to the overlooked sewer networks. In this study, a laboratory-scale sewer reactor system was established to investigate the transformation of FW and the production of sulfide and methane under anaerobic conditions. The transformation of FW in the sewer reactor could result in an increase in the substrate level through hydrolyzing and converting biodegradable substances into preferred substrates. Moreover, the generated substrates from the addition of FW were preferable for the metabolism of key microbes in sewer biofilms. As a result, methane production from the sewer reactor could be enhanced from the addition of FW, whereas sulfide production was not affected at a low sulfate concentration. The findings of this study suggest that the diversion of FW may exert an adverse impact on sewers and the environment in terms of greenhouse gas emission. Hence, more research is necessary to clarify the detailed impacts on FW management and wastewater treatment.

Spinel-like ZnFe2O4 is tailor-made synthesized for catalyzing CO2 hydrogenation, achieving an ultra-high yield (1858.1 g kgcat-1 h-1) of full spectrum alkenes in a three-stage reactor system. This study provides rational design concepts from catalyst to equipment amelioration by combining promoter regulation and ex situ water removal, efficiently catalyzing CO2 into valuable chemical feedstocks with industrial potential.

In this study, we synthesized a novel MAC nanocomposite using almond’s green hull coated with CuS. The whole set of experiments have been conducted inside a batch (discontinuous reactor system) at room temperature. The effectiveness of different parameters in tetracycline removal pH (3, 5, 7, and 9), pollutant concentration (5–100 mg/L), nanocomposite dosage (0.025–1 g/L), and contact time (5–60 min) using newly synthesized nanocomposite were investigated. Based on the results, in the optimal conditions of pH = 9, nanocomposite dosage of 1 g/L, pollutant concentration of 20 mg/L, contact time of 60 min, and room temperature, 95% removal efficiency was obtained. In MAC/CuS/UVC process, the removal of COD and TOC were 76.89% and 566.84% respectively meanwhile, these values in MAC/CuS/UVA process were 74.19% and 62.11%, respectively. The results of nanocomposite stability and magnetic recovery illustrated that the removal efficiency was reduced by 1.5% in the presence of UVC and 5% in the presence of UVA lights during all six cycles. Therefore, this nanocomposite was highly capable of recycling and reuse. It can be concluded that considering the high potential of the synthesized nanocomposite, the photocatalytic efficiency of the MAC/CuS/UVC process in tetracycline synthesis was higher than MAC/CuS/UVA process.

Contaminated soils can become exposure routes of elements toxic to human beings. The health risk of a toxic element by ingestion depends on its bioavailability in the gastrointestinal system, measured in vivo or in vitro. This study aimed to use a novel, versatile reactor (gastrointestinal simulation reactor system to determine bioaccessibility -GSRSB-) to measure lead and arsenic bioaccessibility in the gastric and intestinal phases by applying a modified physiologically based extraction test (PBET). Three composite samples of polluted soils with As (0.50 - 3.25%) and Pb (0.02 - 0.10%) and the certified reference material NIST 2710 were analyzed with this GSRSB-PBET method and the NOM-147 Mexican standard method, which uses an end-over-end shaker. All results were compared to one another. The NIST 2710 results were contrasted with those reported in vivo and in vitro by 14 laboratories. The (GSRSB-PBET) gastric phase ranges were 35.9-55.1 % (As) and 59.6-96.1 % (Pb), while (NOM-147) gastric phases were 35.8-60.4 % (As) and 61.0-70.7 % (Pb). The (GSRSB-PBET) intestinal phase ranges were 39.5-46.9 % (As) and 19.9-31.5 % (Pb). The As and Pb compounds and the stirring technique seem to influence bioaccessibility. On the other hand, the comparison of NIST 2710 results with those reported in vitro and in vivo indicated that As and Pb gastric bioaccessibility obtained with GSRSB-PBET falls into the in vivo results range, while NOM-147 results are higher and fall outside the in vivo range, possibly overestimating the risk. Thus, the proposed method is adequate for modifying the current Mexican Standard Method (NOM-147), which only allows the calculation of Pb gastric bioavailability in vitro.

In accordance with requirements of regulatory and guideline documents on radiation safety for controlled radiation factors for the purposes of operating control, controlled and acceptable levels are established. Any excess of these levels requires the determination of the causes and implementation of actions designed to eliminate the excess. The paper presents the method of calculation of these levels and establishing the levels in practice at the present time, disadvantages of accepted regulations are analyzed. It was shown that existing documents do not take into account some circumstances that define the radiation safety test procedure. In a number of measured control points of the radiological situation and staff radiation exposure, the values of controlled parameters are independent of reactor system mode. In the same points that show the dependence of measured data on a reactor power level, values of controlled parameters may also depend on a mode of pumps and purification system. Furthermore, real-time measurements review has showed that beyond the range of lower limit of measuring range of verification means in the range with nonspecified error, the measured data variance is described by mean value and acceptable error. At the same time, a mean value may be a lower order to lower limit of measuring range. Setting a value of controlled level equal to a sum of a mean of double or tripled root-mean-square deviation depending on the accepted confidence level, a possibility of earlier detection of controlled level excess emerges. In this situation, an exact absolute value of a controlling parameter is not essential as that radiation factor level poses no hazard to life. It is important to capture the onset of significant increase of radiation factor i.e. change of radiological situation.

A set of standardized and realistic aftertreatment catalyst test protocols have been developed by the Advanced Combustion and Emission Control Technical Team in support of the U.S. DRIVE Partnership. The protocols are intended to accelerate the pace of aftertreatment catalyst innovation by enabling the accurate evaluation and comparison of aftertreatment catalyst performance data from various testing and research facilities to maximize the impact of discovery-phase research occurring across the nation. The protocols address a need identified by the Partnership’s industry partners for consistent and accurate metrics for aftertreatment catalyst evaluation and comparison. The protocols consist of a set of standardized requirements and test procedures that sufficiently capture the performance capability of a catalyst technology in a manner that is adaptable in various laboratories. The protocols provide a detailed description of the necessary reactor system, the steps for achieving a desired aged state of the catalyst, all necessary sample pretreatments to be performed prior to testing, and realistic test conditions for evaluating performance. This article details four low-temperature catalyst test protocols applicable to (1) oxidation catalysts, (2) passive storage (and release) catalysts, (3) three-way catalysts, and (4) NH3-SCR catalysts. The catalyst test protocol descriptions are presented in five (5) sections: protocol general guidelines and the four individual catalyst test protocol descriptions. The general guidelines plus the individual protocol description forms the complete low-temperature catalyst test protocol for the application.

Two models of a designed small size lead-cooled fast reactor (LFR) were built by RELAP5-HD to simulate the behavior of the reactor system during pump shutdown accidents, along with different levels of core blockage. Two typical pump shutdown accidents of pump rotor seizure accident and loss-of-pump-power accident were selected to do the simulation and analysis of the behavior of the nuclear power reactor during pump shutdown accidents, when all the safety systems were assumed to be unavailable. A one dimensional vessel-one dimensional core model was built to simulate the long term cooling condition of the pump shutdown accidents under the reactor shutdown or operation conditions. The simulation results would help to analyze whether pump accidents could cause core damage. In order to show the heat removing capability of the coolant in the reactor system, a more detailed one dimensional vessel-three dimensional core model was built to simulate the long term cooling condition of the pump shutdown accidents along with different levels of core blockage accidents.

A laboratory scale experiment of digestate composting was carried out using a reactor system. In this study, conventional physicochemical and biological analyses were carried out and fluorescence excitation-emission matrix (EEM) spectroscopy combined with parallel factor analysis (PARAFAC) was used to assess the maturity and stability during digestate composting. A four-component model was obtained and three components, i.e. fulvic-like (C1 and C3), protein-like (C2), and humic-like (C4) components, were identified. Furthermore, the ratios of each two components were calculated and the relationships with other parameters were established using Pearson correlation analysis. The results showed that the main humification process during digestate composting was the accumulation of fulvic-like substances and that secondary formation occurred at the late stage of digestate composting. Moreover, the EEM–PARAFAC technique could be used as a sensitive and efficient tool for assessing the dynamic changes of digestate composting. The ratio C4/(C1 + C3) is the most suitable indicator in evaluating the stability of digestate composting.

Eucalyptus nitens specimens were thermally modified under open and closed systems. The anatomical characteristics from selected modifications that presented similar mass losses were investigated by...

The present study is based on the investigation of process kinetics of a two-phase anaerobic packed-bed biofilm reactor (AnPBR) with PVA gel beads as biocarrier treating synthetic wastewater-containing molasses. During the steady-state conditions, the reactor system was attributed to 89% of COD removal efficiency. For the comparison of substrate loading removal rate with the prediction of Grau’s second-order model and Stover–Kincannon substrate removal model, AnPBR reactor was run under different hydraulic retention times (HRT) and organic loads. The experimental data obtained from the steady-state conditions showed that Stover–Kincannon model and Grau’s second-order model were the most appropriate models for the proper description of the reactor. Both the Grau’s second-order model and Stover–Kincannon model gave very high correlation coefficients of 98.36% and 98.37%, respectively, for the overall reactor system. Thus, both of these models can be used efficiently for the prediction of behavior and to design the AnPBR reactors.

An automated continuous flow reactor system equipped with inline analysis, was developed and applied in the self-optimisation of a nanoparticle catalysed reaction. The system was used to optimise the experimental conditions of a gold nanoparticle catalysed 4-nitrophenol reduction reaction, towards maximum conversion in under 2.5 hours. The data obtained from this optimisation was then used to generate a kinetic model, allowing us to predict the outcome of the reaction under different conditions. By combining continuous flow nanoparticle synthesis with this approach, the development timeline for these emerging catalysts could be significantly accelerated.

Hybrid nanoflowers materials have recently received great attention in enzyme immobilization applications because of the advantages such as their large surface area, excellent stability, simple, eco-friendly, and cost-effective synthesis. In this study, l-asparaginase which is an important commercial enzyme in the medicine and food industry was selected as a model enzyme. To the best of our knowledge, this study is the first report of designing L-asparaginase@hybrid nanoflowers to enhance its enzymatic performance. L-asparaginase@hybrid nanoflowers were synthesized using ASNase as an organic component and Cu(II) ion as inorganic component. They were characterized by their morphology and chemical point of view by using different techniques. The synthesized L-asparaginase@hybrid nanoflowers exhibited high residual activity at broad pH and high temperature ranges in comparison to free form. Moreover, L-asparaginase@hybrid nanoflowers possessed good reusability and excellent long-time storage stability. Especially, L-asparaginase@hybrid nanoflowers-3 maintained nearly 51 and 75% of its original activity, respectively, after nine consecutive catalytic cycles and storage at 30 degrees C for 4 weeks. The results indicated that these hybrid nanoflowers will be promising carrier matrix for the immobilization of ASNase in biotechnological applications with improved catalytic properties.

Globally, 2.7 billion people are using onsite sanitation systems, particularly in low income, high density settlements (LIHDS) in urban areas of developing countries. However, treatment technologies to manage the faecal sludge (FS) generated from these systems are often not in place, leading to high risks for environmental and public health. The development of replicable and effective technologies for FS treatment is key in addressing this challenge. This research focused on development of an innovative FS stabilisation technology and addressed key constraints in anaerobic FS treatment: inadequate pathogen inactivation and limitations in biochemical energy recovery. The developed two-stage reactor system consists of an acidogenic reactor fed with mixtures of FS and market waste to facilitate pathogen inactivation, and a subsequent methanogenic plug-flow reactor for enhanced methane production. Due to its potential for application as an off-site FS treatment technology at any scale, receiving any type of faecal matter, collected from different types of sanitary systems, the system provides an option for FS stabilisation for LIHDS. Additionally, the research evaluated the limitations of sanitation provision in LIHDS, and proposes methods for creating an enabling environment for fullscale implementation of onsite systems. The presented results contribute to designing appropriate sanitation interventions in LIHDS.

Supercritical water-cooled reactor (SCWR), as the only water-cooled reactor of six Generation-IV reactor systems, has obtained a significant attention. SCWR is designed as a once-through water-cooled reactor system because water as the working fluid is considered as a single-phase fluid under the supercritical pressure.

Nuclear design of a reactor system involves the successful demonstration and optimization of safety, economics, reliability, and operations. In order to achieve these objectives, iPWRs share many of the same nuclear design principles as any other reactor types, in particular those of the large PWRs. This chapter describes (i) the important safety design criteria and principles in nuclear design of reactors, and in particular, iPWRs, (ii) what design features are used to achieve a viable and economic nuclear design, and (iii) how the iPWR designers and vendors have addressed the design principles and features in their respective reactors.

The reactor pool tank liner is a part of the reactor system structure and components (SSCs) and is currently as an object of reactor aging management activities. The age of the reactor tank has reached 41 years, therefore it is necessary to study tank aging from various aspects, one of which is the neutronic influence. The benchmarking neutron flux by Monte Carlo N-Particle Transport Code (MCNP) and experiment measurement was carried out to determine the value in the aluminum tank. Meanwhile, the duration of the operation is based on the value of power generation ≈ 43.556 MWD and the average operating power is 100 kW. The analysis result show that neutrons fluence on the reactor tank for thermal and fast energy are in the order of ∼ 1016 neutron/cm2 and ∼ 1015 neutron/cm2, respectively. Based on the reference, the effect of neutron fluence on aluminum will have an effect on the fluence value of 1022 neutron/cm2. This study shows that the neutron fluence received by the reactor tank is still far from its physical capability limit.

International audience; During the recent ten years, the estimation of future uranium demands has changed greatly, and SFR competitiveness is called again into question. In this context, a planning of plutonium multi-recycling in PWRs for the near-term decades has been announced in France, which replaces the objective of future SFR deployment. However, the mid-term policy concerning the future reactor system is always uncertain, and the demand of SFR deployment may re-increase significantly. This study looks into this possibility and analyzes the consequences of such back and forth between different plutonium multi-recycling strategies. The newly developed methodology of robustness assessment is applied to the problem, considering the objective disruptions to take into account the deep uncertainties about nuclear future. Two prior trajectories of plutonium multi-recycling, one involving the use of MIX fuel in PWRs and the other considering the SFR deployment, are analyzed first. The disruption of the strategy using MIX is then supposed under the re-consideration of future SFR deployment. To quantify the impacts of using MIX on deployment timing, we investigate the earliest time for which the fleet substitution with SFRs can be completed. To supplement, the prior strategy of SFR deployment is also disrupted under the context of halting the start of new SFR. The plutonium multi-recycling in PWRs, regarded as adaptive strategy, aims to minimize the idle plutonium. In these robustness assessments, numerous outputs of interests are analyzed, in order to provide a comprehensive evaluation of consequences of prior strategies, regarding the uncertain disruptions and optimal readjustments.

The first criticality of the high temperature engineering test reactor (HTTR) was achieved on November 10, 1998. After improvement of the reactor system and performance confirmation, the rise-to-power test was started in September 1999. The HTTR achieved the full power of 30 MW at a reactor outlet coolant temperature of about 850°C in December 2001, and the reactor outlet coolant temperature of 950°C was achieved in April 2004. After that, various operations such as high temperature operation at 950°C and safety demonstration tests were conducted until December 2010, and the HTTR has been suspended since the Great East Japan Earthquake in 2011. The high temperature operation at 950°C showed that the HTTR has enough performance to supply high temperature heat to a heat utilization system such as a hydrogen production system. Furthermore, the inherent safety of HTGR was confirmed by the safety demonstration tests.

Based on the analysis of the deficiencies of HAZOP, it is presented that the integration of HAZOP with LOPA can obtain the HAZOP-LOPA evaluation method, which can further reduce the risk level of the sulfonated reaction system. For the analysis of the sulfonation reactor system in the gaseous SO 3 sulfonation process, in the analysis process, the HAZOP method is first used to identify and analyze the existing accident risk in the system. The deviation analysis shows that the temperature of the sulfonation reactor system is easy to lose control and the conversion efficiency is too low. Furtherly using the layer of protection analysis, considering the high temperature of the reactor system after the unefficient cooling water as the initial event, analysis the failure consequences and calculate the probability of accident consequences, and assess the risk level of the existing protection value. The inherent risks and residual risks determine the risk controlling measures so that the risks can be taken under control. The results show that the HAZOP-LOPA evaluation method can quantify the risk and improve the effect of safety analysis. It is an effective method to improve the accuracy and scientificity of risk assessment results.

Acetic acid and formic acid are volatile pollutants leading to degradation of some heritage materials. They are usually determined in museum environments with various types of passive samplers. In this work, SKC UMEx 200 passive samplers, originally intended for sampling of $$\hbox {NO}_{2}$$ NO 2 and $$\hbox {SO}_{2}$$ SO 2 , have been validated for sampling of these organic acids. The sampling rates, extraction efficiency, loss through reverse diffusion or during storage, capacity, and detection limits were determined for both acids. For laboratory exposure, a known concentration of both acids was prepared in a flow-through reactor system at controlled temperature and humidity, the samplers were extracted, followed by analysis using ion chromatography. The sampling rates were determined to be 16.7 ml/min for acetic and 17.7 ml/min for formic acid and the detection limits for 7-day exposure were determined to be $${2.1}\,{\upmu }{\rm g/m}^3$$ 2.1 μ g / m 3 for acetic and $${1.9}\,{\upmu }\hbox {g/m}^3$$ 1.9 μ g/m 3 for formic acid. The validated method was finally used for sampling of air in two case studies at the National Museum of Slovenia, where the concentrations in the range of 2–$${54}\,{\upmu }\hbox {g/m}^3$$ 54 μ g/m 3 were determined.

We report on the experimental demonstration of a modular solar dish-reactor system to perform the splitting of CO2 into separate streams of CO and O2 via a 2-step thermochemical cycle based on ceria redox reaction. Since only the reduction step requires a solar input, the system comprises two solar reactors mounted side-by-side on a sun-tracking dish concentrator coupled to a secondary rotating reflector that allows for simultaneous operation of both reactors by alternating the concentrated solar input between them. Each solar reactor consists of a cavity-receiver containing a reticulated porous structure made of ceria exposed to a solar radiative power input of 6 kW at 2360 suns entering through the cavity's aperture. Process stability and system robustness are demonstrated by performing fully automated consecutive redox cycles.