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Enzymatic production of nucleotide sugars on a multigram scale presents a challenge, as only a few processes have been reported for large-scale nucleotide sugar production. They rely primarily on batch synthesis and employ exceptional amounts of enzymes. This study introduces a novel approach for the multigram-scale production of nucleotide sugars with a continuous fed-batch membrane reactor. We successfully synthesized five main nucleotide sugars: UDP-Gal, UDP-GalNAc, UDP-GlcA, GDP-Man, and CMP-Neu5Ac on a multigram scale. Efficient biocatalyst utilization results in high performance, including space-time yield (STY, g*L−1h−1), total turnover number (TTN, g product per g enzyme), and an efficient product formation rate (g/h) suitable for industrially relevant bioprocesses. The established continuous-fed batch reactor system produced up to 8.2 g CMP-Neu5Ac in three consecutive productions in less than 15 h with satisfying TTNs of 91 g Product /g Enzyme. Continuous production of UDP-GlcA over 28 h resulted in a final product amount of 14.8 g and TTN of 493 g P /g E. This process enables the production of nucleotide sugars with stable product formation, requiring minimal technical equipment for multigram quantities of nucleotide sugars at the laboratory scale. Notably, the system exhibited robustness and flexibility, allowing its application to various enzymatic nucleotide sugar synthesis cascades. [Display omitted] • New process for the multi-gram scale production of nucleotide sugars. • Multigram-scale production of five out of the nine main nucleotide sugars. • High TTNs possible in a lab-scale approach. • High throughput of substrates using small quantities of enzyme. • Continuous production over up to 28 h. [ABSTRACT FROM AUTHOR]

Like skeletal muscles having a fibrous structure, conducting polymers can actuate upon electrical stimulation and can be shaped into fibers. Through textile assembly strategies of such fibers, complex actuating architectures are possible. However, state‐of‐the‐art strategies using short pieces of yarn, which compel manual integration, are not fully taking advantage of textiles. To manufacture actuating textiles that best exploit textile properties like softness and pliability, and to enable production upscaling, a production of continuous, actuating fibers is presented here. These fibers are produced from commercial polyamide 6/6 filaments by first continuously dip‐coating in a modified commercial poly(3,4−ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) dispersion before the electropolymerization of polypyrrole (PPy), where the fibers are withdrawn continuously through an electrolyte solution containing the pyrrole monomer. By employing a cyclic dip‐coating with individual viscosity, drying temperature, and withdrawal speed for each layer, and by adjusting the tension, speed, and applied potential of the electropolymerization, their isotonic strain is enhanced threefold. Their specific tension, at 400 µN tex−1, reaches slightly higher than human skeletal muscle fibers. Furthermore, these continuous actuating fibers produced on the meter are processable in an industrial knitting machine. This study anchors the development of textile muscle fibers for future textile muscles. [ABSTRACT FROM AUTHOR]

With the concept of Industry 4.0 production processes are moving towards autonomy and intelligence. Technologies equipped with artificial intelligence (AI) are involved into processes that are more and more digitized. Collaborative technologies are a feature of discrete processes. The automotive industry has achieved many successes in the process innovation towards smart factories. Other plants, such as smelters or coal mining are also striving to develop smart manufacturing with integrated computer systems to support processes. A continuous production is different from a discrete or batch production. Industry 4.0 concept is focused on discrete production (with high level of automation and robotization of manufacturing) meanwhile there is a gap in implementation of these approach in the continuous production. The objective of the publication is to prepare and design the integrated computer management system based on processes realized in coal and steel manufacturing. Coal and steel production are key elements in a chain of any industrial manufacturing e.g. automotive or machinery engineering. These processes are crucial in building of smart value chain. In our paper we present the structure of processes for the continuous production. Based the processes model we proposed the next steps to build the smart manufacturing for continuous production.

Lipid production using microalgae is challenging for producing low-value-added products. Harnessing microalgae for their fast and efficient CO2 fixation capabilities may be more reasonable since algal biomass can be utilized as a precursor for various products in a biorefinery approach. This study aimed to optimize the productivity and efficiency of Microchloropsis salina biomass production in open thin-layer cascade (TLC) photobioreactors under physical simulation of suitable outdoor climate conditions, using an artificial seawater medium. Continuous operation proved to be the most suitable operating mode, allowing an average daily areal productivity of up to 27 g m−2 d−1 and CO2 fixation efficiency of up to 100%. Process transfer from 8 m2 to 50 m2 TLC photobioreactors was demonstrated, but with reduced daily areal productivity of 21 g m−2 d−1 and a reduced CO2 fixation efficiency, most probably due to increased temperatures at midday above 35 °C. An automated overnight switch-off of the circulation pumps was implemented successfully, reducing energy and freshwater requirements by ~40%. The ideal conditions for continuous production were determined to be a dilution rate of 0.150–0.225 d−1, pH of 8.5, and total alkalinity of 200–400 ppm, facilitating efficient pilot-scale production of microalgal biomass in TLC photobioreactors. [ABSTRACT FROM AUTHOR]

A microstructured mixer, equipped with double-tube, swirl, and contraction flow channels, is proposed for the stable and continuous solvothermal synthesis of metal-organic framework (MOF) particles. The synthesis of Cu-BTC nanoparticles from copper nitrate and benzene 1,3,5-tricarboxylic acid ethanol solutions was conducted across temperatures ranging from 283 to 523 K. This study investigated the effects of temperature, flow rate, and mixing sequence on product yield and particle diameter. Comparative analysis of the results helped in highlighting the advantages of this mixer in preventing preheating of the starting solution and subsequent clogging.

Polymer composite fibers with superior properties such as excellent combined strength and toughness and biocompatibility can be used in high-tech applications of braided protective devices and smart wearable, however the research of high-performance polymer composite fiber remains in the infant stage. Here we present a strategy to produce strong and tough anisotropic polymer nanocomposite fibers with orientedly aligned salt rods using mechanical stretching-assisted salting-out treatment. The prepared nanocomposite fibers have a tensile strength of up to 786 ± 2.7 MPa and an elongation at break of 81%, and the anisotropic fibers exhibit good transmission of mechanical vibration in the longitudinal direction with high resolution. During the fabrication process, the salt builds up into oriented rods during the directional salting process, and the polymer is confined to the 150 nm domain between the rods after the solvent is completely evaporated, giving the nanocomposite fibers superior mechanical properties. The presented strategy can be applied to the continuous mass production of nanocomposite fibers and is also generalizable to other polymer nanocomposites, which could extend the applicability of nanocomposite fibers to conditions involving more demanding mechanical loading and mechanical vibration transmission. [ABSTRACT FROM AUTHOR]

This work reports about a combined additive manufacturing technology – concrete spraying and extrusion – for a continues production of precision concrete elements for modular civil construction. In order to achieve the goal, a fine‐grained concrete mix was developed that covers the technical production properties for both spraying and extrusion. In a next first step, a spray‐extrusion multi‐tool nozzle was developed and tested for spraying and extrusion of the fine‐grained concrete mixture. In addition to complete the robot‐assisted flow production process, force transmission elements were developed, which can be automatically integrated into the extruded concrete matrix in the non‐cured green state in accordance with the load. This holistic automated production technology opens new fields of application in the construction industry that were previously not possible with classic methods. [ABSTRACT FROM AUTHOR]

Purpose: This paper presents application solutions related to the use of Fourth Industrial Revolution technologies in industry. The aim of the paper is including in a discussion about new trends in the development of information systems supporting monitoring, control and diagnostics of production processes. The objective was realised using the example of continuous production in steelworks. Design/methodology/approach: The aim of the paper was realized in theoretical and practical part of the paper. The empirical part of the was the form of a case study – approach to mathematical model for predicting the enthalpy of foundry ladles. Findings: The conclusion is simply: each industrial branch has to use own transformation path towards Industry 4.0. Practical implications: Prepared approaches - based on analysis of trends in data processing control system in the continues production - can be used to build algorithm of predictive model in its system. Research limitations/implications: The authors are aware of the limitations resulting from the excessive generality of the model, but they ensure that they will continue research on the implementation of Industry 4.0 technology in the metallurgical (metal) industry, with particular emphasis on the continuous course of manufacturing processes. Originality/value: The value of the paper are prepared approaches to mathematical model for predicting the enthalpy of foundry ladles. [ABSTRACT FROM AUTHOR]

This work focuses on the production, in continuous mode, of ozone using a new electrochemical cell, specially designed and manufactured with 3-D printing to produce in a very efficient way high concentrations of this powerful oxidant. The gaseous ozone produced is tested in the degradation of a synthetic waste containing methomyl. The new cell has been characterized in terms of flow distribution, mass transfer, and production of ozone, being able to reach efficiencies as high as 9.5 g/kWh, which may be even competitive with those produced with the corona discharge technology. The prototype manufactured with an electrode area of 1.5 cm2 can produce a stream containing 30 mg/h of O3. This stream can be used to degrade methomyl. However, the direct bubbling was not found to be very efficient and activation of ozone with the simultaneous irradiation of UV light or the dosing of hydrogen peroxide was needed to improve performance, showing important synergism. The efficient removal of methomyl from wastewater opens the window for the development of alternative technologies to direct anodic oxidation based on the production and dosing of gaseous oxidants such as ozone. The operation of these new technologies does not depend on the salts contained in wastewater and prevents the deterioration in the quality of the waste because it does not leave any residue after application in the treated waste.

Perovskite solar cells have garnered significant attention as the next-generation photovoltaic devices. After more than a decade of dedicated research, commercializing these cells is now on the horizon. One of the primary focuses for developers aiming at large-scale industrial production is cost reduction. To achieve cost savings in perovskite solar cell manufacturing, researchers have successfully devised cost-effective room-temperature perovskite solar cells for fabricating perovskite films at room-temperature. Additionally, they have developed full room-temperature perovskite solar cells, where the entire solar cell is fabricated at room temperature. These cells excel in terms of their straightforward processing, low energy consumption, and continuous production capability, rendering them highly suitable for industrial applications. This article is intended to provide an overview of the latest advancements in room-temperature perovskite solar cell research. It will summarize commonly utilized methods for their fabrication, delve into the significant implications of full room-temperature perovskite solar cells for the commercialization of perovskite solar technology, and conclude by outlining various production techniques for room-temperature perovskite films. Furthermore, this article will offer insights into the future development directions of room-temperature perovskite solar cells and full room-temperature perovskite solar cells. [ABSTRACT FROM AUTHOR]

This work focuses on the production, in continuous mode, of chlorate and hydrogen peroxide, using tailored electrochemical cells specially designed to obtain high efficiencies in these electrochemical processes. Then, these chlorate and hydrogen peroxide electrochemically produced were mixed for the chemical formation of chlorine dioxide, susceptible to be used for environmental applications. In this work, not only the prototype's conceptualization, design, and 3-D printing manufacturing are realized, but also the characterization of the cells in terms of fluid dynamics, mass transfer, and production of the target compounds is made. The chlorate prototype, with an electrode area of 78.5 cm2, produced up to 1200 mg h−1 of a chlorate solution with a purity of 50 %. The hydrogen peroxide prototype, with an electrode surface area of 10.9 cm2, produced up to 9 mg h−1 of hydrogen peroxide with a concentration of up to 70 mg L−1. The chlorine dioxide was produced continuously with these compounds (HClO 3 and H 2 O 2), operating at low H 2 O 2 /HClO 3 ratios and with a highly acidic supporting media. The oxidant was effectively transferred to a gaseous stream through air stripping. It was then introduced to solutions containing iodine or methomyl to confirm its ability to oxidize substances and to assess its potential use for environmental applications. These findings indicate that using Gaseous Oxidants Mediated Electrochemical Technology (GOMET) with chlorine dioxide is a viable solution for environmental remediation, offering promising prospects for future research on this topic. [Display omitted] • ClO 2 can be produced in continuous mode from electrogenerated HClO 3 & H 2 O 2. • Tailored conceptualization, design, and 3-D printing manufacturing of cells. • Coulombic efficiencies in the production of H 2 O 2 of 50 % and 30 % for HClO 3. • Gaseous chlorine dioxide successfully applied to oxidize iodine and methomyl. [ABSTRACT FROM AUTHOR]

The continuous production of high-quality, few-layer graphene nanosheets (GNSs) functionalized with nitrogen-containing groups was achieved via a two-stage reaction method. The initial stage produces few-layer GNSs by utilizing our recently developed glycine-bisulfate ionic complex-assisted electrochemical exfoliation of graphite. The second stage, developed here, uses a radical initiator and nitrogen precursor (azobisisobutyronitrile) under microwave conditions in an aqueous solution for the efficient nitrogen functionalization of the initially formed GNSs. These nitrile radical reactions have great advantages in green chemistry and soft processing. Raman spectra confirm the insertion of nitrogen functional groups into nitrogen-functionalized graphene (N-FG), whose disorder is higher than that of GNSs. X-ray photoelectron spectra confirm the insertion of edge/surface nitrogen functional groups. The insertion of nitrogen functional groups is further confirmed by the enhanced dispersibility of N-FG in dimethyl formamide, ethylene glycol, acetonitrile, and water. Indeed, after the synthesis of N-FG in solution, it is possible to disperse N-FG in these liquid dispersants just by a simple washing–centrifugation separation–dispersion sequence. Therefore, without any drying, milling, and redispersion into liquid again, we can produce N-FG ink with only solution processing. Thus, the present work demonstrates the 'continuous solution processing' of N-FG inks without complicated post-processing conditions. Furthermore, the formation mechanism of N-FG is presented. [ABSTRACT FROM AUTHOR]

The Resource-Constrained Project Scheduling Problem (RCPSP) is a significant and important issue in the field of project management. It arises during project planning when resources must be allocated among tasks with specific time constraints. Solving this problem enables the optimization of project execution time, minimization of resource costs, and increased efficiency of the entire team's work. Due to the increasing complexity of projects, the development of new methods and algorithms to solve RCPSP is relevant nowadays. The existing methods for obtaining approximate solutions with guaranteed accuracy are characterized by high computational complexity and are often ineffective in considering the specific constraints of the problem. Fast heuristic approaches also have several drawbacks related to fine-tuning algorithm parameters and strong dependence on the quality of the initial solution. This paper investigates the features of the linear integer programming (LIP) model to solve RCPSP. The proposed LIP model is universal and scalable, enabling it to fully consider all specific aspects of the problem. The paper provides a construction algorithm of a functional space of the model and discusses the estimation of complexity. From the estimation of the mentioned algorithm's complexity, it is observed that the general complexity of the proposed approach is proportional to a controlled parameter of the LIP. Increasing this controlled parameter can significantly reduce the dimensionality of the initial problem, thus leading to the effectiveness of the LIP model-based approach in terms of computational resources. An upper bound for the value of this parameter is obtained for a special case of the RCPSP. Using the obtained balanced value, a numerical experiment was carried out on real-world samples. [ABSTRACT FROM AUTHOR]

The article discusses the current level of development of automation technologies for continuous production, taking into account the compliance with the requirements of the fourth industrial revolution Industry 4.0. A new classification of the levels of industrial safety of production processes is proposed, taking into account the stages of the plan for the localization and elimination of emergency situations. The states of the life cycle of continuous production are determined, taking into account the proposed classification. A mathematical model of the states of the life cycle of continuous production has been developed and their interrelations have been determined. Based on the analysis of the statistical data on the states of the life cycle of flat glass production, the probabilities of transitions between the states of the production life cycle are determined. As a result of the statistical analysis of the probabilities of state transitions for the production of sheet glass, it became possible to use the apparatus of Markov processes. The use of the apparatus of Markov processes made it possible to assess the probabilities of finding continuous production in each state of the life cycle. The MathCAD software package computed the probabilities for each state of the life cycle of sheet glass production. To determine the probabilities of life cycle states in the MathCAD software package, simulation modeling has been performed. The comparison of the results of calculating the probabilities of the states of the life cycle of production, obtained by the method of simulation and analytical calculation, has been carried out. The values of the calculated probabilities of the state of the life cycle of continuous production make it possible to use the "Arbiter" software package for the analysis of durability, survivability, safety, technical risk, expected damage and production efficiency.

In this article, a sliding mode control (SMC) is applied to regulate the delivered power of a symmetrical six-phase induction generator. For this, the SMC strategy associated to the field-oriented control strategy is used in order to adjust the inner current loops of a squirrel cage six-phase induction generator (SC6PIG). In this way, the control algorithm switches between positive and negative feedback according to the position of the operating point in the phase plane. This technique guarantees the robustness of the SC6PIG in case of the loss of one to three stator phases or machine converter legs. The switching line slope and the initial operating point have been set so that the system starts with a negative feedback, then it continuously switches back and forth to positive feedback in order to maintain the desired trajectory of the system. The simulation and experimental results demonstrate the effectiveness and the robustness of this technique since the delivered power of the SC6PIG presents the same dynamics in healthy or faulty modes with one to two phase losses. [ABSTRACT FROM AUTHOR]

Marine fish cage culture is a fledgling industry in Iran. The continuous supply of juvenile fish is needed for cage farms, and it is the bottleneck of this industry. Therefore, selecting a suitable species for breeding and rearing that guarantees the stable supply of juvenile fish is the key to the continuity and success of this industry. To date, in Iran, several different species of marine fish have been introduced for breeding and rearing, however there have been various opinions among fisheries experts regarding target species selection. In this study, several indicators considered and categorized as principal factors affecting the target species selection, then the characteristics of fish used for breeding and rearing were compared with scientific evidence, and consequently, a species was nominated as the target one. Also, a native proper species for utilization in the marine aquaculture industry in Iran introduced. [ABSTRACT FROM AUTHOR]

The growing use of bacteriophages in the fields of agriculture, agri-food, veterinary treatments, and medicine involves the quantitative production of these bacteriophages. In this study, we propose a bacteriophage production protocol that can easily be transposed to industry. We used a cellstat production system because the latest studies have shown that it is the most suitable process for the production of phages due to volumetric productivity, safety (limitation of co-evolution), and flexibility (choice of growth rate criteria). Sizing of the assembly used makes it possible to extrapolate the results to industrial production. The production conditions are indicated precisely, which would allow manufacturers to adapt the protocol to their own equipment. We propose experimental conditions in order to obtain a stable Escherichia coli population, qualitatively and over time, and production of high-titer T7 bacteriophages. The optimized production conditions (yield, cost and simplicity of the process) are: a buffered peptone water medium concentration of 11 g L -1 and a dilution rate of 1.6 h -1 . Under these conditions, we obtained a production of 7.35×10 16  plaque-forming units (PFU) L -1 day -1 with a concentration of 9.8×10 12  PFU mL -1 . The strength of this work lies in its focus on industrial applicability., (Copyright © 2024 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

The continuous production of high-quality, few-layer graphene nanosheets (GNSs) functionalized with nitrogen-containing groups was achieved via a two-stage reaction method. The initial stage produces few-layer GNSs by utilizing our recently developed glycine-bisulfate ionic complex-assisted electrochemical exfoliation of graphite. The second stage, developed here, uses a radical initiator and nitrogen precursor (azobisisobutyronitrile) under microwave conditions in an aqueous solution for the efficient nitrogen functionalization of the initially formed GNSs. These nitrile radical reactions have great advantages in green chemistry and soft processing. Raman spectra confirm the insertion of nitrogen functional groups into nitrogen-functionalized graphene (N-FG), whose disorder is higher than that of GNSs. X-ray photoelectron spectra confirm the insertion of edge/surface nitrogen functional groups. The insertion of nitrogen functional groups is further confirmed by the enhanced dispersibility of N-FG in dimethyl formamide, ethylene glycol, acetonitrile, and water. Indeed, after the synthesis of N-FG in solution, it is possible to disperse N-FG in these liquid dispersants just by a simple washing–centrifugation separation–dispersion sequence. Therefore, without any drying, milling, and redispersion into liquid again, we can produce N-FG ink with only solution processing. Thus, the present work demonstrates the ‘continuous solution processing’ of N-FG inks without complicated post-processing conditions. Furthermore, the formation mechanism of N-FG is presented.

The global utilization of H2O2 is currently around 4 million tons per year and is expected to continue to increase in the future. H2O2 is mainly produced by the anthraquinone process, which involves multiple steps in terms of alkylanthraquinone hydrogenation/oxidation in organic solvents and liquid–liquid extraction of H2O2. The energy‐intensive and environmentally unfriendly anthraquinone process does not meet the requirements of sustainable and low‐carbon development. The electrocatalytic two‐electron (2 e−) oxygen reduction reaction (ORR) driven by renewable energy (e.g. solar and wind power) offers a more economical, low‐carbon, and greener route to produce H2O2. However, continuous and decentralized H2O2 electrosynthesis still poses many challenges. This Minireview first summarizes the development of devices for H2O2 electrosynthesis, and then introduces each component, the assembly process, and some optimization strategies. [ABSTRACT FROM AUTHOR]

The Resource-Constrained Project Scheduling Problem (RCPSP) is a significant and important issue in the field of project management. It arises during project planning when resources must be allocated among tasks with specific time constraints. Solving this problem enables the optimization of project execution time, minimization of resource costs, and increased efficiency of the entire team’s work. Due to the increasing complexity of projects, the development of new methods and algorithms to solve RCPSP is relevant nowadays. The existing methods for obtaining approximate solutions with guaranteed accuracy are characterized by high computational complexity and are often ineffective in considering the specific constraints of the problem. Fast heuristic approaches also have several drawbacks related to fine-tuning algorithm parameters and strong dependence on the quality of the initial solution. This paper investigates the features of the linear integer programming (LIP) model to solve RCPSP. The proposed LIP model is universal and scalable, enabling it to fully consider all specific aspects of the problem. The paper provides a construction algorithm of a functional space of the model and discusses the estimation of complexity. From the estimation of the mentioned algorithm’s complexity, it is observed that the general complexity of the proposed approach is proportional to a controlled parameter of the LIP. Increasing this controlled parameter can significantly reduce the dimensionality of the initial problem, thus leading to the effectiveness of the LIP model-based approach in terms of computational resources. An upper bound for the value of this parameter is obtained for a special case of the RCPSP. Using the obtained balanced value, a numerical experiment was carried out on real-world samples.

Based on the developed continuous production system of sodium phenol carboxylation reaction, several types of discharging devices are proposed, which are suitable for the case where the transported particles are not easy to maintain a stable state in the transported fluid. Numerical simulations of the gas-solid two-phase flow characteristics and particle distribution were performed with DPM, and the particle retention ratio and fluid loss degree were proposed to investigate the performance of the discharging devices. The results of simulations and industrial experiments showed that a guide plate installed in the "B" discharging device can solve the accumulation problem, realize the efficient and continuous delivery of the particles, and maintain a uniform distribution of particles. This study can provide a reference for the design of a gas-solid two-phase discharging device, and guide the industrial experimental operation and modification of continuous production systems for sodium phenol carboxylation. [ABSTRACT FROM AUTHOR]

In this work, the emulsion step of a previously reported batch formulation, for production of cellulose acetate (CA) microspheres, is transposed to continuous mode using the NETmix technology. NETmix is a static mixer and reactor that consists of a network of cylindrical chambers operating as mixing zones and interconnected by prismatic channels behaving as plug flow. The quality of the mixture is set by the Reynolds number, and above a critical value (Re > 150) the system evolves to a self-sustained oscillatory laminar flow regime inducing local strong laminar mixing. This patented technology has been used for many applications, such as production of nanocrystalline hydroxyapatite, production of melamine–formaldehyde microcapsules, photocatalysis processes, and Pickering emulsions. Cellulose acetate microspheres containing eugenol as a strong antimicrobial activity component were produced through a solvent evaporation method. Emulsions were produced at different Reynolds number (Re) ranging from 200 to 1200 to evaluate its effect on the size of the resulting microspheres, all of which characterized by a well-defined spherical shape with a rough and a porous shell. The mean diameter decreases from 31 ± 3 µm to 6.5 ± 0.6 µm ongoing from Re = 200 to Re = 500, and a roughly constant value of ca. 6.2 ± 0.9 µm is reached for Re > 500. CA microspheres loaded with eugenol show core contents of 34 ± 4% (w/w) and encapsulation efficiencies of 37 ± 5% and a yield of 54.2 ± 3.5%. The thermogravimetric analysis shows that the CA matrix is thermally stable up to 260 °C and that the eugenol-loaded CA microspheres retain their content up to ca. 100 °C. Scanning Electron Microscopy shows the good adhesion and integrity of selected microspheres on cotton textiles. Release studies of eugenol from treated textiles show that after 84 days, ca. 30% of eugenol was released. This work showed that the NETmix reactor enables controlling the diameter of microspheres by changing Re, leading to the required diameter for the textile application. [ABSTRACT FROM AUTHOR]

The continuous production of biohydrogen by dark fermentation was evaluated in a bench reactor with thermally pretreated anaerobic sludge and synthetic solution of xylose supplemented with nutrients. The reactor operated at 35 °C in semi-continuous mode, which consisted of 16 h feeding cycles (for a hydraulic retention time of 48 h), mixing until completing 19 h of fermentation, and stopping the mixture for 5 h for sedimentation of sludge, followed by the withdrawal of supernatant. The reactor was operated with standard xylose as substrate for 70 days under different chemical oxygen demand (COD) loads and mixing modes during fermentation (intermittent or continuous). A yield of 1.4 mmol H2/mmol xylose was obtained under an organic loading rate of 2.5 g COD/L.d. The consumption of xylose (76.5%) and the H2 yield, which was approximately 41% of the maximum theoretical yield (3.33 mmol H2/mmol xylose with acetic acid as a byproduct), indicates that further studies are necessary to optimize the biohydrogen production in semi-continuous reactors. However, the following parameters led to greater stability of H2 production: adaptation of microorganisms to xylose through prolonged operation in a semi-continuous regime as well as the constant mixing of the reactor contents to reduce gradients of pH, organic acids, and local inhibition of microorganisms. Additionally, an increase in influent alkalinity maintained the pH at levels suitable for H2 producers. [ABSTRACT FROM AUTHOR]

Optimization of production processes has always been one of the cornerstones for industrial enterprises seeking to improve productivity while minimizing the costs involved. A particularly difficult situation is when it is necessary to manage the process of the entire production chain with a continuous supply of raw materials. It is necessary to keep under control the actual production data, current production requirements, and adhere to the international strategy of energy saving. This paper reports a devised optimal dynamic system with a continuous supply of raw materials, which automatically changes the control trajectory in order to reduce the amount of resources used. The theoretical scientific component is represented in the form of an interface model of the system, and the research results are represented in the form of time diagrams that show the verification of the proposed model. The model provides for the interconnection of the chain of such developed dynamical systems, in which the continuity of the process is ensured by buffering systems, and the optimality of operation is enabled by adaptation mechanisms. The time diagrams can demonstrate the interaction of systems and mechanisms that generate information signals through the port sections. At each subsequent control action, the process parameter changes were made within a set range. As a result of a targeted search for permissible controls, the system, driven by the adaptation mechanism, enabled a gradual reduction in the consumption of the energy product and stabilized the intensity of the target product being processed, which made it possible to subsequently avoid shutdowns and restarts of the production line and reduce overall production costs. [ABSTRACT FROM AUTHOR]

The Candida antarctica lipase B (CALB) was embedded in the metal‐organic framework, zeolitic imidazolate framework‐8 (ZIF‐8), and applied in the enzymatic synthesis of L‐ascorbic acid palmitate (ASP) for the first time. The obtained CALB@ZIF‐8 achieved the enzyme loading of 80 mg g−1 with 11.3 U g−1 (dry weight) unit activity, 59.8% activity recovery, and 92.7% immobilization yield. Under the optimal condition, ASP was synthesized with over 75.9% conversion of L‐ascorbic acid in a 10‐batch reaction. Continuous synthesis of ASP was subsequently performed in a packed bed bioreactor with an outstanding average space–time yield of 58.1 g L−1 h−1, which was higher than ever reported continuous ASP biosynthesis reactions. [ABSTRACT FROM AUTHOR]

For the preparation of an immobilized DMAP derivative, 4-dimethyl-aminopyridine (DMAP) is covalently bonded to the surface of nanoscale silicon dioxide by N-alkylation. The immobilized DMAP derivative is first introduced as a catalyst to produce monomenthyl succinate in a mixed solvent system consisting of cyclohexane/acetone (3:2, v/v). The activity of this immobilized DMAP derivative reaches $0.148~\mathrm{mol}_{\mathrm{product}}/\mathrm{mol}_{\mathrm{DMAP}} {\cdot }\mathrm{h}$ and the highest yield of monomenthyl succinate reaches 91.78%. The recyclability and stability of the immobilized DMAP derivative are excellent as demonstrated by its use 10 times during the recycling operation without obvious loss of productivity. This is an efficient heterogeneous catalyst, which can prevent catalyst contamination of the product. In addition, immobilization provides a possibility for continuous production by the use of a packed-bed reactor. Excellent results are obtained, which make the nanoscale silicon dioxide immobilized DMAP derivative a more promising candidate for the industrial production of monomenthyl succinate.

Engineering fast-moving microrobot swarms that can physically disassemble bacterial biofilms and kill the bacteria released from the biofilms is a promising way to combat bacterial biofilm infections. Here, we report electrochemical design of Ag 7 O 8 NO 3 microtorpedoes with outstanding antibacterial performance and meanwhile capable of moving at speeds of hundreds of body lengths per second in clinically used H 2 O 2 aqueous solutions. These fast-moving antibacterial Ag 7 O 8 NO 3 microtorpedoes could penetrate into and disintegrate the bacterial biofilms and, in turn, kill the bacteria released from the biofilms. Based on the understanding of the growth behavior of the microtorpedoes, we could fine-tune the morphology of the microtorpedoes to accelerate the moving speed and increase their penetration depth into the biofilms simply via controlling the potential waveforms. We further developed an automatic shaking method to selectively peel off the uniformly structured microtorpedoes from the electrode surface, realizing continuous electrochemical production of the microtorpedoes. Animal experiments proved that the microtorpedo swarms greatly increased the survival rate of the mice infected by lethal biofilms to >90%. We used the electrochemical method to design and massively produce uniformly structured fast-moving antibacterial microtorpedo swarms with application potentials in treatment of lethal bacterial biofilm infections.

C‐glycosyltransferase (CGT) and sucrose synthase (SuSy), each fused to the cationic binding module Zbasic2, were co‐immobilized on anionic carrier (ReliSorb SP400) and assessed for continuous production of the natural C‐glycoside nothofagin. The overall reaction was 3ʹ‐C‐β‐glycosylation of the polyphenol phloretin from uridine 5ʹ‐diphosphate (UDP)‐glucose that was released in situ from sucrose and UDP. Using solid catalyst optimized for total (∼28 mg/g) as well as relative protein loading (CGT/SuSy = ∼1) and assembled into a packed bed (1 ml), we demonstrate flow synthesis of nothofagin (up to 52 mg/ml; 120 mM) from phloretin (≥95% conversion) solubilized by inclusion complexation in hydroxypropyl β‐cyclodextrin. About 1.8 g nothofagin (90 ml; 12–26 mg/ml) were produced continuously over 90 reactor cycles (2.3 h/cycle) with a space‐time yield of approximately 11 mg/(ml h) and a total enzyme turnover number of up to 2.9 × 103 mg/mg (=3.8 × 105 mol/mol). The co‐immobilized enzymes exhibited useful effectiveness (∼40% of the enzymes in solution), with limitations on the conversion rate arising partly from external liquid–solid mass transfer of UDP under packed‐bed flow conditions. The operational half‐life of the catalyst (∼200 h; 30°C) was governed by the binding stability of the glycosyltransferases (≤35% loss of activity) on the solid carrier. Collectively, the current study shows integrated process technology for flow synthesis with co‐immobilized sugar nucleotide‐dependent glycosyltransferases, using efficient glycosylation from sucrose via the internally recycled UDP‐glucose. This provides a basis from engineering science to promote glycosyltransferase applications for natural product glycosides and oligosaccharides. [ABSTRACT FROM AUTHOR]

We present a framework for the formulation and solution of continuous process scheduling problems. We focus on modeling transient operations such as startups, shutdowns, and transitions between steady states. First, we show how the concept of processing tasks can be generalized to represent continuous processes, including their transient operations. Second, we discuss how to systematically calculate the parameters describing material consumption/production and utility consumption during transient operations. Finally, we present new mixed‐integer linear programming formulations for the scheduling of continuous chemical production. [ABSTRACT FROM AUTHOR]

A novel strategy has been established, in the laboratory scale, for the generation of the popular thermosetting resin phenol formaldehyde (PF; resole), through a continuous process using a tubular reactor, which is usually developed in the commercial scale through a batch process. A refractive index technique is employed to evaluate the optimum residence time within the tubular reactor to obtain a commercial grade equivalent of PF resin. The unreacted free formaldehyde level has been found to be very low in the resole resin prepared by using the new route. The initial characterization of the resin has been done through Fourier transform infrared spectroscopy and gel permeation chromatography. The cure characteristics of the resin have been analyzed through differential scanning calorimetry. The degradation features of the cured resole are investigated using a thermo gravimetric analyzer and the fractured surfaces are analyzed through scanning electron microscopy. It has been confirmed that the adverse effects of a batch reactor process can be significantly reduced by adopting a continuous resin manufacturing process for PF resin which can be successfully extended to commercialization after optimization. [ABSTRACT FROM AUTHOR]

Several drugs have poor oral bioavailability due to low or incomplete absorption which is affected by various effects as pH, motility of GI, and enzyme activity. The gastroretentive drug delivery systems are able to deal with these problems by prolonging the gastric residence time, while increasing the therapeutic efficacy of drugs. Previously, we developed a novel technology to foam hot and molten dispersions on atmospheric pressure by a batch-type in-house apparatus. Our aim was to upgrade this technology by a new continuous lab-scale apparatus and confirm that our formulations are gastroretentive. At first, we designed and built the apparatus and continuous production was optimized using a Box–Behnken experimental design. Then, we formulated barium sulfate-loaded samples with the optimal production parameters, which was suitable for in vivo imaging analysis. In vitro study proved the low density, namely 507 mg/cm3, and the microCT record showed high porosity with 40 μm average size of bubbles in the molten suspension. The BaSO4-loaded samples showed hard structure at room temperature and during the wetting test, the complete wetting was detected after 120 min. During the in vivo study, the X-ray taken showed the retention of the formulation in the rat stomach after 2 h. We can conclude that with our device low-density floating formulations were prepared with prolonged gastric residence time. This study provides a promising platform for marketed active ingredients with low bioavailability. [ABSTRACT FROM AUTHOR]

Objective: To achieve continuous production of fructooligosaccharides (FOS) by recycling of the mycelial cells containing the thermal-stable β-fructofuranosidase in Aspergillus niger without immobilization. Results: The thermal-stable β-fructofuranosidase FopA-V1 was successfully expressed in A. niger ATCC 20611 under the control of the constitutive promoter PgpdA. The engineered A. niger strain FV1-11 produced the β-fructofuranosidase with improved thermostability, which remained 91.2% of initial activity at 50 °C for 30 h. Then its mycelial β-fructofuranosidase was recycled for the synthesis of FOS. It was found that the enzyme still had 79.3% of initial activity after being reused for six consecutive cycles, whereas only 62.3% β-fructofuranosidase activity was detected in the parental strain ATCC 20611. Meanwhile, the FOS yield of FV1-11 after six consecutive cycles reached 57.1% (w/w), but only 51.0% FOS yield was detected in ATCC 20611. Conclusions: The thermal-stable β-fructofuranosidase produced by A. niger can be recycled to achieve continuous synthesis of FOS with high efficiency, providing a powerful and economical strategy for the industrial production of FOS. [ABSTRACT FROM AUTHOR]

Flammability and poor toughness of unmodified PLA limit its applications in various fields. Though ammonium polyphosphate (APP) is a green and effective flame retardant, it has poor compatibility with the matrix, leading to a decrease in mechanical properties. Stereo-complexation greatly improves the strength and heat resistance of traditional PLA. However, the effect of flame retardants on the formation of stereo-complexed crystals and the impact of stereo-complexation on flame retardancy have not been studied previously. In this research, PDLA chains were first in-situ reacted with APP particles for improved interfacial compatibility. By utilizing the characteristic of PLA enantiomers that can form stereo-complexed crystals, near-complete stereo-complexed PLA fibers with flame retardancy were produced via clean and continuous melt spinning. The compatibility between PDLA-g-APP and PLLA matrix was studied by SEM, rheological analyses and DSC. Strength and flexibility of the fibers were simultaneously enhanced compared to traditional PLA due to the synergistic effect of interfacial compatibility and stereo-complexation. Compared to traditional PLA, the peak heat release rate and total heat release in microcalorimetry test were reduced by 33 % and 22 %, respectively. The flame-retardant fibers achieved a V-0 rating in the UL-94 test, and an increase in LOI value from 19.4 % to 28.2 %. [Display omitted] • Synergistic effect of stereo-complexation and interfacial adhesion in FR-PLA • Improved interface compatibility by grafting enantiomeric PLA onto flame retardant • Complete stereo-complexation achieved in FR-PLA fibers • Improvement in toughness accompanied with increase in strength [ABSTRACT FROM AUTHOR]

Abstract Background Recent trends in bioprocessing have underlined the significance of lignocellulosic biomass conversions for biofuel production. These conversions demand at least 90% energy upgradation of cellulosic sugars to generate renewable drop-in biofuel precursors (Heff/C ~ 2). Chemical methods fail to achieve this without substantial loss of carbon; whereas, oleaginous biological systems propose a greener upgradation route by producing oil from sugars with 30% theoretical yields. However, these oleaginous systems cannot compete with the commercial volumes of vegetable oils in terms of overall oil yields and productivities. One of the significant challenges in the commercial exploitation of these microbial oils lies in the inefficient recovery of the produced oil. This issue has been addressed using highly selective oil capturing agents (OCA), which allow a concomitant microbial oil production and in situ oil recovery process. Results Adsorbent-based oil capturing agents were employed for simultaneous in situ oil recovery in the fermentative production broths. Yarrowia lipolytica, a model oleaginous yeast, was milked incessantly for oil production over 380 h in a media comprising of glucose as a sole carbon and nutrient source. This was achieved by continuous online capture of extracellular oil from the aqueous media and also the cell surface, by fluidizing the fermentation broth over an adsorbent bed of oil capturing agents (OCA). A consistent oil yield of 0.33 g per g of glucose consumed, corresponding to theoretical oil yield over glucose, was achieved using this approach. While the incorporation of the OCA increased the oil content up to 89% with complete substrate consumptions, it also caused an overall process integration. Conclusion The nondisruptive oil capture mediated by an OCA helped in accomplishing a trade-off between microbial oil production and its recovery. This strategy helped in realizing theoretically efficient sugar-to-oil bioconversions in a continuous production process. The process, therefore, endorses a sustainable production of molecular drop-in equivalents through oleaginous yeasts, representing as an absolute microbial oil factory.

Sorption-enhanced steam reforming of ethanol (SE-SRE) with in-situ CO 2 removal is an environmentally friendly and sustainable approach for hydrogen production. Researches on continuous production of high-purity H 2 by SE-SRE over the modified Li 4 SiO 4 sorbent were conducted using two parallel reactor in this work. The low cost Li 4 SiO 4 derived from rice husk ash (RHA) is a promising high-temperature CO 2 sorbent. However, the poor adsorption kinetics of RHA-Li 4 SiO 4 sorbent at low CO 2 concentration is the major challenge. The metallic elements (K, Ca, Al, Mg) were employed to modify the RHA-Li 4 SiO 4 for efficient CO 2 capture. The developed sorbents were characterized and tested to study the role of dopants on the crystal, textural, microstructure and CO 2 adsorption kinetics and cyclic stability. Results indicated that K doping effectively inhibited the growth of crystal aggregation and resulted in a fluffy morphology with abundant pores and higher specific surface area, while the addition of Ca, Al and Mg formed a nubby structure with larger particle size. K-doped RHA-Li 4 SiO 4 exhibited the best CO 2 uptake properties and the optimal K doping molar content was 0.02 with the maximum capture capacity of 34.16 wt%, which is higher than 27.1 wt% of pure RHA-Li 4 SiO 4. Then, the effect of operating conditions on the enhancement behaviors was considered in the SE-SRE system. High-purity H 2 (above 96%) was achieved by coupling K(0.02)/RHA-Li 4 SiO 4 sorbent with Ni-based catalyst under the optimum condition (T: 525 °C, liquid hourly space velocity: 0.9 mL/(g·h), sorbent/catalyst: 4 and steam/carbon: 8.0). The adsorption activity of K(0.02)/RHA-Li 4 SiO 4 maintained at a high level in ten SE-SRE/regeneration cycles. Finally, a scheme including two parallel fixed-bed reactors was designed and operated periodically for continuous production of high-purity H 2. The reaction switching time was shown to depend strongly on the pre-breakthrough time and operating conditions. As the reaction switching time was 40 min, the products were always only H 2 and CH 4 (no CO and CO 2 appear) and the H 2 purity remained above 90% during 400 min, confirming high purity hydrogen stream can be obtained continuously. • Li 4 SiO 4 sorbent from rice husk is modified to promote CO 2 adsorption kinetics. • K-doped Li 4 SiO 4 with best CO 2 uptake properties was applied in SE-SER system. • Operating conditions were tested for continuous production of high-purity H 2. • High purity H 2 above 90% can be obtained continuously in two parallel reactors. [ABSTRACT FROM AUTHOR]

Industrial research departments and chemical engineering institutes have begun to adopt additive manufacturing technologies, such as stereolithography for producing special types of reactors for continuous production. Microreactors have been widely used to improve the mass and heat transfer processes between immiscible liquid-liquid phases, but with the disadvantage of requiring sophisticated technology for their manufacture. In this paper, an approach for producing millireactors by stereolithography and rapid optimization of millireactor design with circular cross-section is presented. Transesterification of vegetable oils with alcohols is widely used method for biodiesel synthesis, generally taking place in a batch reactor. Microreactors due to their short residence times and high biodiesel yields are currently being explored for continuous production, but have disadvantages in low production volumes and high pressure drops. To overcome above-mentioned problems, millireactors with channel diameters from 1.5 mm to 3.5 mm were produced in order to investigate the impact of channel dimensions on conversion of sunflower oil to fatty acid methyl esters (FAME). Transesterification reaction of sunflower oil using methanol with addition of KOH base catalyst to FAME was monitored by Fourier-transform infrared spectroscopy, gas chromatography, and nuclear magnetic resonance. Results show that millireactors with smaller channel dimensions and processes with higher temperatures at certain residence times can be used to achieve better biodiesel yield in much shorter time than batch reactors. In addition, continuous way of FAME production in millireactors is presented. Production in millireactors provided an improvement when compared to microreactors because they have low pressure drops and higher production volumes. [ABSTRACT FROM AUTHOR]

Gastroretentive systems may overcome problems associated with incomplete drug absorption by localized release of the API in the stomach. Low-density drug delivery systems can float in the gastric content and improve the bioavailability of small molecules. The current publication presents verapamil–HCl-containing solid foam prepared by continuous manufacturing. Production runs were validated, and the foam structure was characterized by micro-CT scans and SEM. Dissolution properties, texture changes during dissolution, and floating forces were analyzed. An optimized formulation was chosen and given orally to Beagle dogs to determine the pharmacokinetic parameters of the solid foam capsules. As a result, a 12.5 m/m% stearic acid content was found to be the most effective to reduce the apparent density of capsules. Drug release can be described by the first-order model, where 70% of verapamil dissolved after 10 h from the optimized formulation. The texture analysis proved that the structures of the solid foams are resistant. Additionally, the floating forces of the samples remained constant during their dissolution in acidic media. An in vivo study confirmed the prolonged release of the API, and gastroscopic images verified the retention of the capsule in the stomach.

For the preparation of an immobilized DMAP derivative, 4-dimethyl-aminopyridine (DMAP) is covalently bonded to the surface of nanoscale silicon dioxide by N-alkylation. The immobilized DMAP derivative is first introduced as a catalyst to produce monomenthyl succinate in a mixed solvent system consisting of cyclohexane/acetone (3:2, v/v). The activity of this immobilized DMAP derivative reaches 0.148 molproduct/molDMAP·h and the highest yield of monomenthyl succinate reaches 91.78%. The recyclability and stability of the immobilized DMAP derivative are excellent as demonstrated by its use 10 times during the recycling operation without obvious loss of productivity. This is an efficient heterogeneous catalyst, which can prevent catalyst contamination of the product. In addition, immobilization provides a possibility for continuous production by the use of a packed-bed reactor. Excellent results are obtained, which make the nanoscale silicon dioxide immobilized DMAP derivative a more promising candidate for the industrial production of monomenthyl succinate. [ABSTRACT FROM AUTHOR]

An efficient and green aqueous–solid system was introduced for phospholipase D‐mediated transphosphatidylation. γ‐(2,3‐epoxypropoxy) propytrimethoxysilane was covalently bound to silica and esterified by acetic acid, which acted as an anchor molecule to facilitate the adsorption of phosphatidylcholine (PC) in aqueous solutions. Obtained silica‐adsorbed PC was successfully used for transphosphatidylation to produce phosphatidylserine (PS). The PC loading and PS yield reached 98.8 and 98.3%, respectively. A new model was proposed to illustrate the adsorption and enzymatic processes. Moreover, this aqueous–solid system provides a promising way for the continuous production. Four kinds of phospholipids were biosynthesized in the pack‐bed reactor. The stability of the aqueous–solid system was excellent, as demonstrated by its use 30 times without any loss of the productivity. The product was eluted by coconut oil and manufactured into microcapsules. Toxic agents were completely avoided in the whole production process. [ABSTRACT FROM AUTHOR]

BACKGROUND: Natamycin is an antibiotic which shows strong inhibition and wide spectrum against most fungi. It is produced mainly through batch and fed‐batch fermentations, which are characterized by long culture time, low productivity and enormous discharge of waste biomass. In the present study, a new strategy using immobilized cells was proposed for continuous natamycin production via repeated batch culture to address these shortcomings. RESULTS: A combination of cell immobilization and repeated batch culture was employed to continuously produce natamycin in both flasks and a 5‐L fermenter. The immobilized cells served as seeds and producing strains, and exhibited high vitality of cell growth and natamycin biosynthesis during six cycles of repeated batch culture. The application of the new strategy led to remarkable decrease of lag phase and removal of time intervals among traditional multiple batch cultures, resulting in a 32.10% reduction of total culture time. In addition, the new strategy showed 1.8‐fold higher natamycin titre and 195.24% productivity improvement relative to traditional strategies, and decreased waste biomass discharge, thus consituting a high‐efficiency, environmentally friendly strategy for natamycin production. CONCLUSION: This study proposes a new approach to continuous natamycin production, which not only promoted natamycin productivity, but also reduced the fermentation time and the biomass residue discharge. Moreover, it provides reference points for the continuous production of other biochemicals by filamentous bacteria or funguses, which could be of great significance in industrial antibiotics production. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The production process consists of activities that are required in transforming an input set to valuable outputs. Input set includes human resources, raw materials, components, equipments, energy, money, information, etc. Market globalization, increasing global competition, and more complex products result in application of new production and logistics technologies, methods and business processes. Fast changing market environment and fluctuating customer demands require efficient operation of production and logistics processes. In this study the intermitted and continuous production processes are introduced. The essence of Industry 4.0 conception is also detailed.