Continuous Process Research Articles

Effect of pulsed electric field processing on microbial and enzyme inactivation in blended plant-based milk alternatives: A case study on a microbial challenge test for a non-presterilized oat-based beverage enriched with pea protein

Microbial and enzyme inactivation by pulsed electric field (PEF) treatment was assessed in a blended plant-based milk alternative (PBMA) containing oats and pea protein without the application of presterilization. This was conducted to investigate a novel approach that permits PEF process validation for PBMA containing heat-labile components (protein and starch). Continuous PEF processing at moderate field strengths (9–10 kV/cm) combined with mild preheating (30–45 °C) for 25 s was applied over a range of specific energy inputs (77–245 kJ/L). Selective plating permitted bacterial enumeration of inoculated surrogate organism, despite the presence of natural microbial contaminants in the non-presterilized product. A minimum 5-log reduction of inoculated surrogates Escherichia coli and Listeria innocua alongside native microbiota was identified after preheating to 35–45 °C followed by PEF at 192–215 kJ/L. α-amylase activity was reduced by up to 89% during a similar PEF treatment (205 kJ/L, 40 °C). Overall, continuous PEF combined with mild preheating temperature was shown to achieve microbial inactivation in the pea protein enriched PBMA in compliance with current food safety regulations. Industrial relevancePresterilization is typically applied prior to conducting microbial challenge testing on food products to validate novel pasteurization treatments according to current regulatory requirements that a minimum 5-log reduction of relevant inoculated food pathogens must be achievable. However, for a variety of blended PBMA containing heat-labile proteins, presterilization is not advisable as the occurrence of irreversible changes in the product quality linked to protein coagulation and phase separation will affect the inactivation efficacy during subsequent microbial challenge testing. Hence, an alternative approach is presented utilizing a non-presterilized PBMA and thorough microbiological analysis, combining non-selective and selective plating techniques. This allows an identification of PEF treatment parameter with a minimum 5-log reduction of inoculated surrogate organism alongside naturally present microbial contaminants. This may serve as a valuable guideline for stakeholders in the food industry when addressing the efficacy of novel preservation treatments such as PEF in PBMA products with similar heat-induced product stability challenges.

A two-stage flank correction method for the continuous generation of face gears

Face gear pairs are particularly suitable for application in advanced equipment drivetrains with intersecting shafts. The continuous generation process of face gear tooth flanks using worms offers high machining efficiency, but achieving high accuracy in this process remains a considerable challenge. A two-stage flank correction method for face gears ground by worms on a computer numerical control (CNC) generator is proposed. This method comprehensively involves both the worm dressing and face gear grinding stages, considering the actual machine tool structure and constant offsets among its axes. Firstly, the machining kinematics for both stages are derived and the high-order tooth flank model of the face gears is developed. Secondly, the sensitivity of tooth flank deviations to variations in the kinematic coefficients is analyzed, and the deviations on both flanks of the tooth space generated with initial kinematics are measured. Finally, three cases of correction for the measured deviations are compared using the proposed method. Correcting only the grinding stage is effective and computationally inexpensive, and employing this case for manufacturing face gear tooth flank significantly reduces deviations.

A framework for the in silico assessment of the robustness of an MPC in a CDC line in function of process variability

The shift from batch manufacturing towards continuous manufacturing for the production of oral solid dosages requires the development and implementation of process models and process control. Previous work focused mainly on developing deterministic models for the investigated system. Furthermore, the in silico tuning and analysis of a control strategy are mostly done based on deterministic models. This deterministic approach could lead to wrong actions in diversion strategies and poor transferability of the controller performance if the system behaves differently than the deterministic model. This work introduces a framework that explicitly includes the process variability which is characteristic of powder handling processes and tests it on a novel continuous feeding-blending unit (i.e., the FE continuous processing system (CPS)), followed by a tablet press (i.e., the FE 55). It employs a stochastic model by allowing the model parameters to have a probability distribution. The performance of a model predictive control (MPC), steering the feed rate of the main excipient feeder to compensate for the feed rate deviations of the active pharmaceutical ingredient (API) feeder to keep the API concentration close to the desired value, is evaluated and the impact of process variability is assessed in a Monte Carlo (MC) analysis. Next to the process variability, a model for the prediction error of the chemometric model and realistic feed rate disturbances were included to increase the transferability of the results to the real system. The obtained results show that process variability is inherently present and that wrong conclusions can be drawn if it is not taken into account in the in silico analysis.

Continuous service-based process monitoring using Pareto analysis and start-end case diagram

PurposeThe purpose of this study is to offer a straightforward, cost-effective, and feasible resolution for managers to assess their processes in a live manner using the process mining technique and to identify anomalies in cases that deviate from the standard. Consequently, the findings of this research can be utilized by organizational managers, while process mining vendors can also leverage it as a feature for their solutions.Design/methodology/approachOur two-step method is designed to initially evaluate the level of standardization within the process, followed by identifying its underlying cause. These two steps are aimed at helping managers effectively evaluate their business processes. The steps are: (1). Start-End Case Diagram: This diagram allows for the evaluation of the lead time trend and identification of cases that deviate from the standard trend line in a service-based process. (2). Happy Path Analysis: Pareto law is suggested to identify the most frequent process variants.FindingsThis approach enables organizations to easily identify problematic cases and investigate bottlenecks when deviations from the standards occur.Originality/valueThe novelty of the paper lies in the introduction and utilization of the start-end case diagram, as well as the combination of this diagram with the Pareto law for the identification of happy path and root cause analysis.

Field Education in the Southwest of Paraná: a historical retrospective of field high schools 2007-2023

The objective of this text is to present a historical retrospective of field high schools in the Southwest of Paraná between 2007 and 2023, considering the variation rates in the number of schools, students enrolled in their distribution in the Regional Education Centers – NRE of Francisco Beltrão, Pato Branco and Dois Vizinhos, in order to analyze the historical trends in the last two decades of Field Education in the Southwest of Paraná. Regarding the technical level of the investigation, a bibliographic and documentary approach was combined with a quantitative survey of data from field high schools through official reports and databases to locate and systematize the data intended by the research. In general, the results of the investigation showed that there is a continuous process of decrease in enrolled students, closures of field schools, inadequacy of didactic materials and curricular organization, teacher turnover, lack of continued formation for field school teachers, in addition to the absence of mechanisms to guarantee the permanence of young people and peasant families in the countryside.

To promote a teacher training for a humane society

Reflecting on the training of teachers nowadays compels educators to think about the society in which they live, the vision of school, students/children and young people, teachers, and both the present and the future. To problematize the issue at hand, the following questions need to be reflective: What is the conception of education and training? Can it be associated with the Durkheimian view that education is a vertical action of one generation over another, aimed at transmitting a previously established heritage? Should educators understand education as the promotion of global development, as advocated in the concept of paideia? What meanings of education underlie teacher training? In what society do they live? Do educators see themselves before society as passive members or as active participants who assume the rights and duties of citizenship? What vision do teachers have of those with whom, or about whom, their professional identities are developed: students receiving knowledge transmitted by teachers or people with whom they collaborate to construct socio-historical knowledge? How do they understand themselves as teachers: as technicians or as professionals? What are their perspectives concerning training: a reproduction of institutions or a continuous process for professional emancipation? These questions served as the basis for the development of this article. Using a global approach to our present society and considering ideological-educational concepts and conditions for teaching, we aim to situate and problematize teacher training with the goal of promoting a more humanized society.

Early Ordovician to Early Permian tectonic evolution of the northern Western Kunlun Orogen (NW China): Insights from the Omixia Complex and surrounding rocks

The Palaeozoic tectonic evolution of the Western Kunlun Orogen plays an important role in deciphering the Tethyan tectonic evolution. This study provides new geochronology, geochemistry and Lu–Hf isotopic data of igneous rocks from the Omixia Complex in the eastern section of the northern Western Kunlun, as well as detrital zircon ages from turbidites and meta‐sediments north of it. From the Omixia Complex, the determined ages of five ultramafic–mafic rock samples are approximately 470, 456, 429, 401 and 382 Ma. Two samples of acidic rocks from the same complex yielded ages of approximately 438 and 378 Ma. One pegmatitic plagiogranite sample exhibits feature of accretionary arc granites, while other samples show geochemical characteristics of island arc tholeiite and E‐MORB. Additionally, four turbidite matrix and two limestone samples, with a major peak around ca. 480–500 Ma, have the youngest zircon ages ranging from ca. 481 to 387 Ma, paralleling the age range of igneous rocks in the ophiolitic mélange. The εHf(t) values of these samples reveal a broad spectrum of crustal and mantle processes. The youngest zircon ages of five meta‐sedimentary rock samples north of the Omixia Complex range from ca. 581 to 535 Ma, with peak ages concentrated around ca. 0.9–1.0 Ga. Their provenance characteristics differ from the turbidite matrix in the southern Omixia Complex and from the meta‐sediments in the northern Tiklik terrane with peak ages of ca. 0.8 Ga. A younger limestone sample yielded youngest zircon age of ca. 294 Ma, which is unconformably overlain the Omixia Complex and surrounding older rocks. Based on these new results, combined with previous data, we propose a new tectonic model for the eastern section of the northern Western Kunlun Orogen, suggesting a continuous evolution process of multi‐terrane subduction–accretion collage from the Early Ordovician to the Middle Devonian in the Paleo‐Tethys Ocean, which evolved into an Andean‐type active margin in the Early Permian, contributing to the substantial continental growth of the southern Tarim Craton.

Microfluidic-Based dsRNA Delivery Nanoplatform for Efficient Spodoptera exigua Control.

Nanotechnology-based RNA interference (RNAi) offers a promising approach to pest control. However, current methods for producing RNAi nanopesticides are mainly implemented in a batch-to-batch manner, lacking consistent quality control. Herein, we present a microfluidic-based nanoplatform for RNA nanopesticide preparation using lipid nanoparticles (LNPs) as nanocarriers, taking advantage of the enhanced mass transfer and continuous processing capabilities of microfluidic technology. The dsRNA@LNPs were rapidly formed within seconds, which showed uniform size distribution, improved leaf wettability, and excellent dispersion properties. The delivery efficiency of dsRNA@LNPs was evaluated by targeting the chitin synthetase B (CHSB) gene ofSpodoptera exigua. The dsRNA@LNPs can effectively resist nuclease-rich midgut fluid degradation. Importantly, dsCHSB@LNPs exhibited increased mortality rates, significant reduction of larvae growth, and enhanced gene suppression efficiency. Therefore, a continuous nanoplatform for RNAi nanopesticide preparation is demonstrated by utilizing microfluidic technology, representing a new route to produce RNAi nanopesticides with enhanced quality control and might accelerate their practical applications.

A Novel Image Processing Technique for Weighted Particle Size Distribution Assessment

Objective The objective of the study was to create a reliable method that could be used to evaluate the particle size distribution of samples and pre-mixes in real-world situations, particularly those consisting of typical formulation blends. The goal was to use this method to assess the uniformity of the samples and ensure that they met the required quality standards. The researchers aimed to create a method that could be easily incorporated into the manufacturing process, providing a practical and efficient solution. Significance of review This study demonstrates the use of ImageJ software to analyze the particle size distribution (PSD) of powders. The technique produces qualitative data from microscopy images and quantitative data from analysis of parameters including average diameter, D 10, D 50 , D 90, and standard deviation. The method was tested with various treatments, showing differentiating outcomes in all cases. Key findings The alternate technique provides a rapid and cost-effective method for PSD analysis, surpassing the limitations of sieve analysis. Extensive testing of the method, using a variety of sample types, including typical formulation blends, was performed. The results suggest that the method can effectively assess the morphology of changing materials during batch manufacturing and characterize uniformity in blends. Conclusions The methodology has the capability to identify attributes related to PSD that are typically required to be monitored during manufacturing. The technique allows for accurate and reliable quantification of the attributes through image capture technology. The technique has future potential and has important implications for material science, powder rheology, pharmaceutical formulation development, and continual process monitoring.

Ecosystem Approach in Agrivoltaic Parks Design

The approach to strategic landscape design faces today two challenges: a) the reduction of biodiversity loss b) the mitigation of the negative impact that anthropic activities have on ecosystems. As these are subject to a continuous transformation process, it is essential that the design methodology considers its underlying properties. Hence, arises the need of a profound paradigm shift: integrate better the human landscape into the natural one. To achieve this goal, it is necessary to understand first landscape dynamics as well as the mechanisms that facilitate its resilience and functionality in ecological terms. This is possible thanks to the strategic framework of the Ecological Infrastructure. The landscape proposal must evaluate then the sequence of actions to be carried out, the measures necessary for the improvement of the recognised systems, and its possible evolution over time. Then, according to the Sustainable Development Goals (SDGs), agreed by the EU 2030 biodiversity strategies, the proposal must demonstrate: How biodiversity will improve and how it will be preserved - How ecological processes linked to biodiversity will be upgraded - How cultural and social processes linked to the site will be enhanced - How agricultural and energy production will increase land efficiency - How disturbances will be modulated and controlled. This methodology carried out in Spain aims to demonstrate that the implementation of agrivoltaic fields create an optimal synergy to ensure food security and mitigate the effects of climate change, but also provide the chance to make the landscape more sustainable, efficient, and beautiful.

NMR in Battery Anode Slurries with a V-Shaped Sensor

Inline analytics in industrial processes reduce operating costs and production rejection. Dedicated sensors enable inline process monitoring and control tailored to the application of interest. Nuclear Magnetic Resonance is a well-known analytical technique but needs adapting for low-cost, reliable and robust process monitoring. A V-shaped low-field NMR sensor was developed for inline process monitoring and allows non-destructive and non-invasive measurements of materials, for example in a pipe. In this paper, the industrial application is specifically devoted to the quality control of anode slurries in battery production. The characterization of anode slurries was performed with the sensor to determine chemical composition and detect gas inclusions. Additionally, flow properties play an important role in continuous production processes. Therefore, the in- and outflow effects were investigated with the V-shaped NMR sensor as a basis for the future determination of slurry flow fields.

Iterative feature mode decomposition: A novel adaptive denoising method for mechanical fault diagnosis

Abstract Remaining useful life prediction of rolling bearings highly relies on feature extraction of signals. The use of denoising algorithms helps to better eliminate noise and extract features, thereby constructing health indicators to predict remaining useful life. This paper proposes a novel adaptive denoising method based on iterative feature mode decomposition ( FMD) toI accurately and efficiently extract fault features. The feature mode decomposition (FMD) employs correlation kurtosis (CK) as the objective function for iterative filter bank updates, enabling rapid identification of fault features. To achieve IFMD, the sparrow search algorithm combines sine-cosine algorithm and cauchy variation (SCSSA) to optimize two key parameters in FMD. During the continuous iteration process of the SCSSA algorithm, filter length and number of modes were determined. IFMD does not require empirical setting of initial parameters. During iterative process, the signal is accurately decomposed and the noise is eliminated. Compared with other optimization algorithms, SCSSA has obvious advantages in iterative rate and global optimization. The envelope spectrum feature energy ratio (ES-FER) is used to select decomposed modes, and the mode with the largest ES-FER is chosen as the optimal mode. Bearing fault diagnosis is realized by envelope spectrum analysis of the optimal mode. The numerical simulations and experimental verifications both validate the effectiveness and superiority of the proposed IFMD in mechanical fault diagnosis.

Assessment of residual prestress in existing concrete bridges: The Kalix bridge

The direct socio-economic consequences of the deterioration of aging infrastructure systems have triggered a continuous process of revising and updating current design standards and guidelines for critical network components. Specifically, long-term degradation processes demand the analysis and evaluation of vital structural assets such as prestressed concrete bridges. It is crucial to develop theoretically consistent, user-friendly, and non-destructive methodologies that engineering professionals can employ to prevent and mitigate potential catastrophic outcomes during the service life of these bridges. This study provides a thorough review of the available testing methods employed over the years for prestressed concrete bridges and introduces a comprehensive framework for evaluating existing methods for residual prestress force assessment. Through a multi-criteria selection process, the three most feasible tests were designed and carried out on an existing 66-year-old balanced cantilever box girder bridge exposed to freezing temperatures that affected the instrumentation plan and test execution. Finally, predictive models compliant with standard codes were calibrated based on the experimental results and the life cycle loss of prestress forces was evaluated to assess relevant bounding intervals. Findings reveal limited on-site testing and discrepancies between calculated residual forces and predictions by standard codes. The saw cut method showed a 18% difference from the initial applied prestress according to the prestress protocol, suggesting the use of a cover meter and concrete modulus evaluation for improved accuracy. The strand cutting method resulted in a 14% difference, emphasizing the need for stress redistribution assessment. The second-order deflection method showed a 6% difference, indicating a focus on enhanced boundary conditions and thorough sensitivity analysis for future investigations.

Flow Chemistry and Continuous Processing: More Mainstream than Ever!

Flow Chemistry and Continuous Processing: More Mainstream than Ever!

Pilot-scale foam and cast-coated nanocellulose filters for water treatment

AbstractA large variety of substances, for instance heavy metal ions from different sources including mining, industry, and agricultural activities, pollute fresh water sources. Bio-based adsorbents, such as cellulose nanofibers (CNF), have recently been introduced in the process of treating water to remove hazardous pollutants primarily owing to their natural abundance, non-toxicity, and renewability. Surface modification of CNF, e.g. by catalytically oxidising the primary C6-OH groups of CNF selectively into carboxylic (COO−) groups with TEMPO, yields materials that are effective in adsorbing positively charged heavy metal ions, e.g. Cu ions. However, to utilise CNF in continuous processes beyond static, batch-wise adsorption, in particular on (pre-)industrial scale, they need to be immobilised on filter substrates in thin layers and an efficient manner. In this work, we report bio-adsorbent-based filters prepared by coating TEMPO-CNF on viscose filters using two different pilot-scale coating approaches, foam and cast coating. The performance of TEMPO-CNF filters was evaluated in terms of their water permeance as well as adsorption of metal ions including Cu(II) and Ca(II). By foam coating thin layers could be fabricated in a time efficient way facilitating high adsorption capacities (52 mg g−1), whilst by cast coating higher amounts of TEMPO-CNF could be deposited allowing for adsorbing higher absolute amounts (280 mg m−2) of heavy metal ions. Graphical abstract

Integrated techno-economic and life cycle assessment of hydroformylation in microemulsion systems

This paper presents the first integrated techno-economic and life cycle assessment of microemulsion systems being applied for rhodium-catalyzed hydroformylation of long-chain alkenes at industrial scale. The case study describes a projected 150 kt/a production of tridecanal (US gulf coast, 2019). The industrial success of the hydroformylation of short-chain alkenes lies in the continuous recycling of the rhodium-containing water phase. Microemulsion systems can be applied to transfer this concept to long-chain alkenes by overcoming the miscibility gap between the aqueous catalyst phase and the unipolar alkene phase and, moreover, by generating a temperature-induced multi-phase system enabling the immobilization of the catalyst and its continuous recycling, as demonstrated in miniplant operations with dodecene and rhodium/SulfoXantPhos. Customizable simulation models have been developed for scale-up and assessment of the miniplant data. Surprisingly, a profitability-driven sensitivity study indicates a base case optimum at low residence time with low alkene conversion leading to large throughput streams and high raw material purge rates. The comparison to the industrial cobalt-based benchmark system shows an economic advantage regarding net present value (Rh: 68 M$; Co: 62 M$), while about half of the environmental indicators are in favor or equivalent. In a best-case scenario considering zero leaching of expensive rhodium the net present value increases by almost 40% accompanied by a shift to overall lower environmental impacts than the benchmark. In conclusion, the investigated miniplant data suggest microemulsion systems to be competitive when applied in continuous processes at a large scale.

The Interaction Between Cumulative Culture and Gender

In a society characterized by rapid technological and social advancements, we inherit knowledge from our predecessors while simultaneously building upon it to forge new cultural developments, and such process contributes to the Cumulative culture, the continuous and interactive process of adding innovations to a socially heritable unity of knowledge. Considering the prevalence of gender inequality background in our cultures, this academic article explores the intricate relationship between gender equality and cumulative culture. This paper posits that gender, as defined within the constraints of male and female due to various limitations, plays a pivotal role in this cumulative cultural process. As the results, the examination reveals a clear and positive association between cumulative culture and gender equality. Cumulative culture wields a significant influence over children's choices of gender role models, consequently impacting knowledge transmission and children's labor allocation. Simultaneously, fostering gender egalitarianism offers a pivotal avenue for advancing the evolution of human cumulative culture. This paper aims to declare the benefits of gender equality towards cultural evolution and humanity and proposes the potential ways to foster cultural societal thriving.

Cloud service models, business continuity and disaster recovery plans, and responsibilities

Purpose The purpose of this article is to identify the role of cloud computing services in business continuity and disaster recovery plans and delineate responsibilities for their execution. In recent times, there has been a huge upsurge in the usage of cloud service models such as infrastructure-as-a-service, platform-as-a-service, software-as-a-service and disaster recovery-as-a-service. However, in case of an emergency event or during contract negotiations, a question might arise as to who should be accountable and responsible for the content and execution of recovery plans. The main stakeholders in this scenario are cloud service providers and cloud consumers. Design/methodology/approach After a review of academic articles, standards, guidelines and vendor documentation, a proposal for assigning accountability and responsibility for business continuity and disaster recovery plans is presented, based on the RACI (responsible, accountable, consulted and informed) matrix. In this regard, a critical information infrastructure protection plan, a disaster recovery plan, an information systems contingency plan and a business continuity plan have been elaborated on in the article. Findings RACI matrices are presented for three general cloud service models and for three DRaaS models (managed, assisted and self-service). Accountability and responsibilities depend on the deployed cloud service model and the roles of cloud service providers and cloud consumers. Originality/value The proposed model for accountability and responsibility assignment provides a guideline for the allocation of responsibilities to roles not only during recovery but also during contract negotiations between cloud service providers and cloud consumers. By delving into business continuity and disaster recovery processes and activities, similar yet nuanced RACI matrices should be developed, as presented in this paper. They need to be customised for the specific context.

An in-line dye tracer experiment to measure the residence time in continuous concrete processing

An in-line dye tracer experiment to measure the residence time in continuous concrete processing

Challenges in the Synthesis and Processing of Hydrosilanes as Precursors for Silicon Deposition.

Liquid hydrosilanes are required for the production of silicon films. The silicon layers can be processed for electronic devices like transistors or thin-film solar cells. Hydrosilanes are highly reactive and pyrophoric. Therefore, the synthesis of these compounds is challenging and dangerous. The available synthesis methods for hydrosilanes are reviewed and compared. Hydrosilanes are highly attractive compounds, which can be processed as liquids with printing technology to amorphous silicon films on nearly any solid substrate. The silicon layers can be processed for electronic devices like transistors or thin-film solar cells. The endothermic character of hydrosilanes with their positive enthalpies of formation results in favorable properties for processing. The larger the molecules, the lower their decomposition temperature and the higher their photoactivity. Cyclic hydrosilanes such as cyclopentasilane and cyclohexasilane can be easily deposited. The branched neopentasilane is more difficult to deposit but yields better-quality films after processing. The key challenge is the complex synthesis of the precursors and the hydrosilanes. The available preparative methods are presented in this review and their advantages and disadvantages are evaluated. The following synthesis methods are presented and discussed in this article: Wurtz coupling and other reductive coupling processes, dehydrogenative coupling of silanes, plasma synthesis of chlorinated polysilanes, amine- or chloride-induced disproportionations, and transformation of monosilane to higher silanes. Plasma synthesis is already carried out today as a continuous industrial process. The most effective synthesis methods in the laboratory are currently amine- and chloride-induced disproportionations. There is a great need to further optimize the syntheses of hydrosilanes and to develop new simple synthesis variants.