Journal Of Engineering Research Articles

Bibliometric analysis and systematic review on the electrokinetic remediation of contaminated soil and sediment.

Electrokinetic remediation (EKR) is a proficient, environmentally friendly separation technology for in-situ removal of contaminants in soil/sediment, distinguished for its ease of implementation and minimal prerequisites compared to other remediation technologies. To comprehensively understand the research focus and progress related to EKR of contaminated soil/sediment, a bibliometric analysis was conducted on 1593 publications retrieved from the Web of Science Core Collection (WOSCC) database. This analysis utilized data mining and knowledge discovery techniques through Bibliometrix, VOSviewer, and CiteSpace software. The results revealed a rising trend in annual publication numbers, with China leading in the number of publications. The primary journals in this field included the Journal of Hazardous Materials, Chemosphere, and Separation and Purification Technology. The primary disciplines contributed to this field included "Environmental Sciences", "Engineering, Environmental", "Engineering, Chemical", and "Electrochemistry". Keyword co-occurrence and burst analysis indicated that current EKR-related research mainly focuses on the remediation of soil/sediments contaminated by heavy metals (HMs) and organic pollutants (OPs). Furthermore, the EKR remediation improvement method emerged as the prevailing and future research hotspots and development directions. Future research could integrate numerical simulations and various methodologies to predict and assess the migration of pollutants and the efficiency of remediation efforts. Additionally, these studies could explore the effects of EKR on the physicochemical properties and microbial diversity of soil/sediment to provide a theoretical foundation for applying EKR in soil/sediment remediation.

Effectiveness and safety of acupuncture for cancer-related hiccups: a systematic review and meta-analysis.

The use of acupuncture in cancer treatment is expanding. Nevertheless, the efficacy and safety of acupuncture in alleviating cancer-related hiccups remains uncertain and inconclusive. We conducted a systematic search across eight databases: PubMed, China National Knowledge Infrastructure Database, WanFang, China Science and Technology Journal Database, SinoMed, Web of Science, Cochrane, and Embase, covering the period from their inception to July 2023. Literature was screened based on predefined PICOS inclusion and exclusion criteria, and the risk of bias was assessed using the Cochrane Risk of Bias tool. Data synthesis was performed using Review Manager 5.3 software and R studio 4.4. Additionally, we conducted a frequency analysis of acupoint usage. A total of nine randomized controlled trials (RCTs) involving 580 patients were included in the analysis. The risk of bias assessment indicated a high risk of bias in all nine RCTs, primarily due to blinding of participants and personnel and random sequence generation (selection bias). The meta-analysis revealed that acupuncture significantly reduced the symptoms of cancer-related hiccups compared to pharmacological treatment (relative risk (RR) = 1.83, 95% confidence interval (CI) [1.53, 2.20], p < 0.001, I2 = 27%). In terms of onset time, acupuncture demonstrated a shorter duration of onset compared to pharmacological treatment (mean difference (MD) = -8.71, 95% CI [-23.32 5.89], p < 0.01, I2 = 100%). Furthermore, acupuncture exhibited a significant improvement in sleep, eating, and appetite scores compared to pharmacological treatment (MD = 0.68, 95% CI [0.07, 1.29], p = 0.03; MD = 0.68, 95% CI [0.07, 1.30], p = 0.03; MD = 0.66, 95% CI [0.08, 1.25, p = 0.03]). The frequency of acupoint usage was analyzed, with ST36 and PC6 being the most frequently used acupoints. Regarding adverse events, acupuncture exhibited favorable safety profiles compared to other control groups. The meta-analysis results suggest that acupuncture has a positive effect on the efficacy rate for cancer-related hiccups, as well as improvements in quality of life and time to effect response. However, due to the high risk of bias and quality limitations of the included studies, no conclusive evidence currently supports the efficacy of acupuncture. High-quality, evidence-based research is still needed to confirm the effectiveness of acupuncture in treating cancer-related hiccups. https://www.crd.york.ac.uk/prospero/, CRD42023451403.

Enhancing the visibility and impact of Cambodian scientific journals through Open Journal System (OJS): An editorial review

The Ministry of Education, Youth, and Sport (MoEYS) in Cambodia is currently working on an initiative to enhance the visibility and impact of Cambodian scientific journals by implementing Open Journal Systems (OJS) in the country's higher education institutions (HEIs). During a workshop at Svay Rieng University, MoEYS emphasized its objectives to modernize the administration and publication of scholarly work, thereby facilitating more efficient peer review and open access. The objective of increasing the number of Cambodian journals indexed in international databases, including Scopus, the ASEAN Citation Index (ACI), and Web of Science among others, is a critical component of vision. This will enhance the academic credibility and global visibility of Cambodian research. At present, Cambodia maintains 52 scientific journals in various disciplines, including agriculture, education, health, and technology. While some journals, such as the Cambodia Journal of Public Health and the Cambodia Education Review, continue to operate, others have discontinued publication or encountered difficulties in maintaining consistency. The Ministry's initiative will be instrumental in the revitalization of the academic publishing infrastructure in the country and will offer essential support to journals that are currently grappling with sustainability challenges. Additionally, Cambodian journals can make a substantial contribution to regional and global academic discourse, encourage research collaborations, and attract higher-quality submissions by indexing in international databases. This action is consistent with Cambodia's overarching objective of internationalizing higher education and cultivating a more robust research culture, thereby guaranteeing the extensive recognition and global standards of local research. The strategic endeavor to enhance the quality of research output, establish Cambodia's scholarly community as a critical contributor to addressing national and global challenges, and cultivate academic partnerships is exemplified by the strategic use of OJS and the aspiration to index in prestigious databases.

Navigating tomorrow's healthcare: Exploring the future of healthcare navigation with VR, AR, and emerging technologies: A comprehensive review

Effective navigation is critical to optimizing patient outcomes and improving the patient experience in today's rapidly growing healthcare landscape. The potential influence of VR, AR, and other emerging technologies on healthcare navigation is examined in this article. Patients may meet medical experts, participate in their treatment plans, and better apprehend their conditions through the immersive adventures offered by virtual and augmented reality. In addition to augmented and virtual reality, wearable technologies, AI, and the IoT are transforming real-time health monitoring and customization, augmented reality, virtual reality, and healthcare navigation. This study synthesizes the literature, examines case studies, and looks at real-world scenarios to provide insights into the potential, difficulties, and opportunities of utilizing these technologies to develop a patient-centric healthcare system. Academic databases were examined, including PubMed, Google Scholar, IEEE, and other relevant public health, medicine, and healthcare technology journals. The data gathered from case studies, actual-life scenarios, and literature reviews is synthesized to provide a comprehensive overview of the current landscape, opportunities, challenges, and prospects of leveraging VR, AR, and emerging technologies in healthcare navigation, including key terms such as emerging technologies, VR, AR, and healthcare navigation. The main discussion topics are targeted treatment, data visualization, medical research, and virtual and augmented reality. Additional worries are raised about privacy, data security, and ethical ramifications. Though these technology has some exciting aspects, problems like unequal access and technical constraints must be overcome before it can be extensively used. In order to overcome these obstacles and pave the way for a more effective, patient-centered healthcare system, virtual reality, augmented reality, and other cutting-edge technologies may be used to reform healthcare navigation.

Celebrating the 150th Anniversary of the Journal of Geotechnical and Geoenvironmental Engineering

Celebrating the 150th Anniversary of the <i>Journal of Geotechnical and Geoenvironmental Engineering</i>

Concomitant virus infection increases mortality and worsens outcome of acute pancreatitis: A systematic review and meta-analysis.

Acute pancreatitis (AP) is a major health threat, with a high mortality rate in severe forms. Though alcohol and bile-induced factors are the most common causes, increasing evidence suggests that viral infections such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and human immunodeficiency virus (HIV) may also trigger AP development. Our study aims to explore this association in greater detail. After the PROSPERO registration, we systematically searched PubMed, Embase, Cochrane Library, China Science and Technology Journal Database, China National Knowledge Infrastructure, and Wanfang Data Knowledge Service Platform in February 2023. We included studies with the following PECO framework: Population: AP patients, Exposure/Comparison: with/without virus infection, Outcome: mortality, severity, and complications of AP. Pooled odds ratios (OR) were calculated with 95% confidence intervals (CIs). Altogether, 29 cohorts with 2,295,172 patients were identified for the meta-analysis and 858 cases for the qualitative synthesis. Patients with concurrent SARS-CoV-2 infection and AP exhibited heightened odds of in-hospital mortality (OR: 3.15, CI: 2.08-4.76), and necrosis (OR: 1.83, CI: 1.13-2.97). Mild AP was less prevalent in the SARS-CoV-2 group (OR: 0.37, CI: 0.14-0.97) compared to moderately severe and severe AP together. Contrarily, no evidence was found that concomitant HIV infection elevated in-hospital mortality (OR: 1.12, CI: 0.92-1.37) or sepsis occurrence (OR:1.21, CI: 0.41-3.59). Patients co-diagnosed with AP and SARS-CoV-2 infection require heightened attention due to an increased risk of mortality and complications. No evidence was found that HIV infection elevated the risk of a more severe outcome.

Effect of size of capsulorhexis on the outcome of cataract surgery: a protocol for systematic review and individual participant data meta-analysis

IntroductionIn the era of functional intraocular lens (IOL) implantation, it is crucial to investigate the influence of different capsulorhexis sizes (including the diameter of the capsulorhexis, area of the anterior...

Efficacy and Safety of Acupuncture in the Treatment of Radicular Cervical Spondylosis: A Systematic Review and Meta-Analysis.

Cervical spondylotic radiculopathy is a serious and common degenerative disease of the cervical spine due to irritation and compression of the nerve roots of the cervical spine, resulting in a series of clinical symptoms based on sensory, motor and reflex disorders, such as numbness and pain in the neck, shoulders, upper limbs and fingers. Acupuncture is highly effective in treating CSR and has become a common treatment accepted by patients. This study aims to systematically review and analyze existing randomized controlled trials (RCTs) to evaluate the efficacy and safety of acupuncture in the treatment of CSR. We used the following eight databases for literature data search: PubMed, EMBASE, The Cochrane Library, Web of Science, China National Knowledge Infrastructure, China Biology Medicine Disc ( CBMdisc), Wanfang Database and China Science and Technology Journal Database (VIP). The search consisted of randomized controlled studies of acupuncture for CSR between 2000 and 2020 and the methodological quality of the included studies was assessed according to the Cochrane Collaboration's "Risk of Bias Assessment Tool."RevMan 5.4 software was used for statistical analysis only. Study screening, data extraction and statistics, and assessment of the risk of bias of the included studies were performed independently by two reviewers. 27 studies with 3124 patients were included. The results of the meta-analysis of the total efficiency index for acupuncture for CSR were [RR = 1.14,95% CI (1.09,1.19)]. The results of the meta-analysis of the PPI index were [MD = -0.35, 95% CI (-0.61,-0. 09)]. The results of META analysis of the total effective rate, VAS score, PRI(A) score, PRI(S) score and PRI(T) score showed heterogeneity in the studies included for each outcome index, and sources of heterogeneity were sought through subgroup analysis and sensitivity analysis to ensure more stable and reliable data results. The results of the combined meta-analysis showed that the treatment group was significantly more effective than the control group and more effective in lowering the nerves to reduce the pain index in patients with CSR, with a statistically significant difference (P<0.05). This indicates that acupuncture treatment is superior to traction for CSR. Acupuncture is significantly more effective than traction therapy in the treatment of cervical spondylosis and can reduce the pain index of patients with CSR.

Effects of Low-Load Blood Flow Restriction Training on Muscle Volume After Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis.

After anterior cruciate ligament (ACL) reconstruction (ACLR), the function and strength of the quadriceps muscle are essential for a successful recovery. Low-load blood flow restriction training (LL-BFRT) is believed to reduce muscle atrophy and restore muscle function. To systematically analyze the evidence on the effectiveness of LL-BFRT in early rehabilitation after ACLR. Systematic review; Level of evidence, 1. A systematic review and meta-analysis were conducted consistent with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Comprehensive literature searches were performed in several electronic databases-including Cochrane Library (trials), PubMed, Embase, Web of Science, China National Knowledge Infrastructure, WanFang, China Science and Technology Journal Database, and Sinomed-from inception to October 1, 2023. Included were randomized controlled trials in Chinese and English comparing LL-BFRT within 6 weeks after ACLR with conventional rehabilitation training. Bias risk was assessed using the Cochrane Risk-of-Bias 2 tool. The outcomes measured were quadriceps muscle size, knee joint functional scores, balance function, and complications. The effects of LL-BFRT versus conventional rehabilitation were analyzed using standardized mean differences (SMDs) or weighted mean differences (WMDs). A total of 362 studies were initially identified, and 8 were included for analysis. LL-BFRT was significantly more effective in improving quadriceps muscle volume (SMD, 0.37 [95% CI, 0.08 to 0.66]; P = .01) and Lysholm scores (SMD, 0.74 [95% CI, 0.43 to 1.05]; P < .0001) compared with conventional rehabilitation training. However, no significant improvements were observed in the 3 directions of the Y-balance test: anterior (WMD, 0.55 [95% CI, -6.37 to 7.46]; P = .88), posteromedial (WMD, -2.24 [95% CI, -8.76 to 4.29]; P = .50), and posterolateral (WMD, 0.02 [95% CI, -13 to 13.03]; P = 1.0). No complications were reported in any of the included studies. The results of this meta-analysis suggested that LL-BFRT within 6 weeks after ACLR has a more pronounced effect on increasing quadriceps muscle volume and improving Lysholm scores compared with conventional rehabilitation training, with no apparent complications.

The award ceremony of the 2nd Xiamen University Short Video Abstract Contest for Science and Technology Journal Papers Came to a Successful Conclusion

The award ceremony of the 2nd Xiamen University Short Video Abstract Contest for Science and Technology Journal Papers Came to a Successful Conclusion

Trends Use of Technology Research for Early Childhood Education: A Bibliometric &amp; Biblioshiny Analysis (1971-2024)

This study aims to analyze research trends in the use of technology in early childhood education using the Scopus Database. Employing the PRISMA method, the author identified 172 final documents, analyzed through the R Program and VOSviewer. The analysis reveals that research in this area commenced in 1971, with a fivefold increase in publications over the past 20 years. The year 2020 marked the peak with an h-index of 7 and 11 publications (6.39%). Illinois State University emerged as the leading institution with 11 articles (6.39%). The United States is the most productive country, contributing 28 articles (16.28%) and 786 citations (26.85%). Susan Edwards from Australian Catholic University is the most prolific author, achieving an h-index of 5, 253 citations (8.64%), and 5 publications (2.90%). The International Journal of Technology and Design Education is the top source, with 292 citations (9.97%) and 11 publications (6.39%). The document by Blackwell et al. (2014) received the highest citations at 210 (9.02%). The study identified 54 keywords across 7 clusters, recommending "Digital Competence," "Self-directed learning," and "Participatory design" for future research in this field.

Bifunctional Oxygen Electrodes for PEM-Unitized Regenerative Fuel Cell Fabricated By Inkjet Printing

Hydrogen energy storage has proven to be a promising technology to balance the intermittency of renewable energy sources. The high theoretical specific energy density achieved by fuel cell-based systems makes them attractive for energy production, especially for weight and space-sensitive applications.A unitized regenerative fuel cell (URFC) is a single device that works as both an electrolyzer and a fuel cell. The cost of a URFC could be significantly reduced compared to a separate electrolyzer and a fuel cell, since material costs are nearly halved. However, working with a single unit means that the system needs to be designed for both processes, which requires compromises to optimize the overall performance. The performance of URFC systems is significantly affected by the electrode’s fabrication method, so to further develop new and more efficient, durable, and cost-effective bifunctional catalyst layers (CL) for these systems, a more fundamental understanding of the relationship between the CL structure, and performance is required.The most common approach in the literature for fabricating bifunctional CLs for the oxygen electrode in a URFC is to mix both ORR and OER catalysts in a single ink. An alternative method, however, is to deposit layers containing different catalysts next to each other. Even though the latter approach has shown promising results, with the potential for optimization, limited work has been published to date [1-5]; moreover, no study has been done using the inkjet printing technique for the fabrication of either mixed or multilayer arrangement electrodes.In this work, inkjet printing is evaluated as a feasible technique for unitized regenerative fuel cells (URFCs) electrode fabrication and to study the optimal ionomer and catalyst loading of mixed and multi-layer URFC electrodes. A physical mixture of Pt, IrOx, and Nafion ionomer was inkjet printed directly on a Nafion membrane to fabricate varying loading bifunctional oxygen electrodes for a URFC and characterized via scanning electrode microscopy and cyclic voltammetry. The results show coverage of the Pt active sites by IrOx when the catalysts are mixed, which means that reducing the IrOx catalyst compared to platinum, i.e., 3:1 Pt-IrOx ratio is necessary for optimum performance [6]. A catalyst loading study shows that a round-trip efficiency of 51% at 500 mA/cm2 can be obtained using 0.67 mgPtIrOx/cm2 PMG catalyst loading in the oxygen electrode, resulting in one of the highest efficiencies by the amount of catalyst reported. The results are compared with a multilayer arrangement electrode, showing that the partial coverage of Pt sites by the IrOx can be avoided by printing the catalysts in separate layers. The Pt to Ir ratio was critical to the successful operation of the multilayer arrangement when the IrOx layer was in contact with the GDL, due to the poor conductivity of the CL, which at the highest loadings provided a barrier for the electrons to reach the Pt layer near the membrane. A catalyst ratio study showed optimum performance with a 9:1 Pt to Ir ratio, obtained with the electrode with the IrOx layer on top of the Pt CL and these on top of the PEM. In this case, the total catalyst loading was 0.56 mgPtIrOx/cm2, reaching a round-trip efficiency of 51% at 500 mA/cm2 and 44% at 1000 mA/cm2, one of the highest RT efficiency for a multi-layer arrangement and by the amount of catalyst of any constant gas bifunctional electrode reported in the literature.[1] Guobao Chen, Huamin Zhang, Haipeng Ma, and Hexiang Zhong. Electrochimica Acta, 54(23):5454–5462, 2009.[2] Sebastian Altmann, Till Kaz, and Kaspar Andreas Friedrich. Electrochimica Acta, 56(11):4287–4293, 2011.[3] Woong Hee Lee and Hansung Kim. Journal of The Electrochemical Society, 161(6):F729, 2014.[4] Byung-Seok Lee, Hee-Young Park, Min Kyung Cho, Jea Woo Jung, Hyoung-Juhn Kim, Dirk Henkensmeier, Sung Jong Yoo, Jin Young Kim, Sehkyu Park, Kwan-Young Lee, Electrochemistry Communications, 64:14–17, 2016.[5] Seunghoe Choe, Byung-Seok Lee, and Jong Hyun Jang. Journal of Electrochemical Science and Technology, 8(1):7–14, 2017.[6] L Padilla Urbina, J Liu, N Semagina, and M Secanell. Journal of Power Sources, 580:233448, 2023.

Notched Gate and Graded Gate Oxide Processing for Reduced Capacitance Application in RF MOSFETs

As the demands of RF applications are rising, optimization of internal MOSFETs capacitances is a key issue to improve the cut-off frequency. In this abstract we report the development of a novel N-MOS architecture processed on 8-inch SOI wafers. This architecture has a gate oxide with variable thickness along the channel and a reduced bottom gate length aiming at minimizing Gate to Drain/Source capacitance (1) (2). This improvement on Gate to Drain/Source capacitance mainly comes from a decrease in overlap capacitances as described in (3).The new process flow is composed as usual until Poly-Si gate etching. By controlling the species flow and process time during plasma etching steps, over etch at the bottom of the gate is performed (fig.1(a,b)). Poly-Si gate notching engineering is possible due to reduction of the passivation layer thickness at the bottom of the gate during plasma etch. As described in (4) the gate is first etched using a HBr/CL2/O2 chemistry until reaching close to the bottom of the gate, allowing the formation of a passivation layer made of SiOxCly and the anisotropy of the etch. To etch the remaining thickness HBr flow is augmented while CL2 and O2 flow are reduced, preventing formation of passivation layer. This leads to isotropic etch of the bottom gate and reduction of the gate length as regard to the top Poly-Si dimension. This over-etch reduces the physical gate length without changing the effective and the on-mask gate lengths, leading to overlap capacitance reduction.To produce gate oxide with variable thickness under gate sidewalls a two-steps process is performed. First, full plate oxide is grown before poly-Si deposition to act as middle gate thickness. Then undercut is performed, consisting of lateral etching of the gate oxide under gate sidewall after gate etch (fig.2.a). To achieve this undercut, hydrofluoric acid (HF) wet etch has been chosen. First trials with very low HF concentration become quickly saturated leading to small lengths under gate sidewalls (fig.2.b). Then more acidic solutions were used allowing satisfying undercut lengths (fig.2.c).Finally rapid thermal oxidation (RTO) is performed to obtain an oxide bird beak at both gate side as both Poly-Si gate and Si from the active region react with ambient O2 in the chamber. This leads to a gate oxide with variable thickness along the channel (fig.3(a.b)) which has both effects: to get smoother poly-Si foot and a down step in the active between channel and Source/Drain regions. During this process step, a built-in spacer on the gate sides for LDD implantation is formed. RTO process step has grown a thicker oxide over Source/Drain areas which has to be reduced to allow an accurate LDD implantation, this is done by anisotropic etching. After these new steps, the process goes back to a standard N-MOS process flow.Some early versions of the notched gate have been investigated (5), and these experiments and details on processing recipe seem promising for electrical results. As poly-Si foot has been smoothed and graded gate oxide (GGO) on top of overlaps region is formed. It would allow a reduction in parasitic capacitances improving cut-off frequency of RF applications.References RF LDMOSFET with Graded Gate Structure. Xu Shuming, Foo Pan Dow. Toronto : s.n., 2001. 1th International Symposium on Power Semiconductor Devices and ICs. ISPSD'99 Proceedings. pp. 221-224. DOI:10.1109. Notched-Gate pMOSFET with ALD TiN/High-κ Gate Stack Formed by Selective Wet Etching. Zhang, D. Wu and J. Lu and P.-E. Hellström and M. Östling and S.-L. s.l. : The Electrochemical Society, Inc., 2004, Electrochemical and Solid-State Letters, Vol. 7, p. 228. 10.1149/1.1795612. A simple efficient model of parasitic capacitances of deep-submicron LDD MOSFETs. Fabien Pregaldiny, Christophe Lallement,Daniel Mathiot. s.l. : Solid State Electronics, 2002, Vol. 46, pp. 2191–2198. https://doi.org/10.1016/S0038-1101(02)00248-4. Design of notched gate processes in high density plasmas. J. Foucher, G. Cunge, L. Vallier, and O. Joubert. s.l. : AVS: Science & Technology of Materials, Interfaces, and Processing, 2002, Vols. Journal of Vacuum Science & Technology B 20,. http://dx.doi.org/10.1116/1.1505959. Notched gate MOSFET for capacitance reduction in RF SOI technology. al, L. Antunes et. s.l. : 2023 IEEE International Conference on Design, Test and Technology of Integrated Systems (DTTIS), 2023. doi: 10.1109/DTTIS59576.2023.10348288. Figure 1

Model-Based Development of Control Strategies for a Fuel Cell Air Supply System and Experimental Verification at Flight-Relevant Conditions

The performance of hydrogen PEM fuel cell systems can be optimized by means of pressurization of the cathode air, especially in aviation, where at in-flight conditions the pressure of the ambient air is significantly lower as at on-ground conditions. To provide the inlet air at optimal conditions (p, T, rH) during flight, an air supply system is required and in an all-electric aircraft the compression should happen by means of an electric centrifugal compressor. A challenge for the operation of a pressurised fuel cell system at high altitudes is the control of the compression system. Any unstable operation like compressor surge has to be avoided, since it can damage both the fuel cell stack and the compressor itself. For the development of such an air supply system, a combined experimental and modeling approach was chosen.A hydrogen PEM fuel cell system was characterized at nominal and at low cathode pressures to obtain the behavior at flight relevant conditions and an experimental air supply system containing electric compressor, intercooler, humidifier, cathode volume and throttle valve at the outlet has been set up and used for the development, parameterization, and validation of a model for the compression system. The model is based on the Greitzer model 1,2, and has been extended to also represent the additional components between the compressor and the throttle valve (intercooler, humidifier, and cathode volume) 3. It is now able to predict the transient response of the entire air supply system to changes in the reference values of compressor speed and valve opening angle and the resulting mass flow changes and pressures within the individual components.The model and the data from the fuel cell system were used for the development of improved control strategies, that make it possible to operate the system safely in a wide range of operating conditions. Unstable situations, like compressor surge, are avoided by these control strategies even in the highly varying conditions during a flight. The developed control strategies are verified on the hardware of the experimental setup and tested under realistic flight conditions in a low-pressure climate chamber.References Greitzer, E. M. Surge and Rotating Stall in Axial Flow Compressors—Part I: Theoretical Compression System Model. Journal of Engineering for Power 98, 190–198 (1976).Gravdahl, J. T. & Egeland, O. Compressor Surge and Rotating Stall. (Springer London, London, 1999). doi:10.1007/978-1-4471-0827-6.Frank, D., Bauer, C. & Willich, C. Modeling of the cathode air supply for a pressurized hydrogen fuel cell system in airborne applications. Proceedings of the Aerospace Europe Conference 2023 (2023) doi:10.13009/EUCASS2023-218.

Highly Porous Ir-Based Catalyst-Integrated Electrode for Efficient Proton Exchange Membrane Water Electrolyzer

Proton exchange membrane water electrolyzer (PEMWE) is the most promising green hydrogen production device suitable for responding to the intermittency of renewable energy sources [1]. However, anodes in acidic and oxidizing environments require the use of noble Ir that is resistant to harsh conditions. Although many efforts have been made to develop efficient and robust Ir-based catalysts, most have focused on developing catalysts in powder form and evaluating half-cells based on aqueous model systems consisting of three-electrode using rotating disk electrode (RDE). The membrane electrode assembly (MEA)-based PEMWE system has significant differences in operating conditions (temperature, electrolyte, catalyst loading, substrate type, etc.) from the half-cell system, and therefore, the high performance and durability in the half-cell system do not ensure the same results within the PEMWE system [2]. This means that the developed catalysts should be applied to a single cell and its compatibility assessed.In this study, a catalyst-integrated electrode was fabricated by forming an Ir-based catalyst on a Ti fiber felt used as an anode PTL in the PEMWE system, and applied directly to the anode without using a binder. The application of a powder-type catalyst to MEA is complicated through many steps such as powder production, ink preparation, and catalyst layer coating, requiring a lot of time and cost. In addition, when coating the catalyst layer, it is physically deposited together with a polymer binder, which not only blocks the active sites of the catalyst but also causes the problem of lowering the electrical conductivity of the catalyst layer [3]. On the other hand, the catalyst-integrated electrode is a simple method of growing on PTL, providing good electrical conductivity and excellent mechanical stability, and can be directly applied to the PEMWE system without using a binder. Our Ir-based catalyst-integrated electrode prepared through electrochemical reaction showed excellent OER activity (248 mV at 10 mA cm− 2) and durability (50 h at 200 mA cm− 2) in a half-cell system based on excellent physicochemical/electrochemical properties, and also showed the similar results when applied to a single-cell (performance of 6.5 A cm− 2 @ 2.0 Vcell with a degradation rate of only 1.58 mV h− 1 for 100 h stability test at 2 A cm− 2), showing feasibility for industrial use.[1] S. Shiva Kumar, V. Himabindu, Hydrogen Production by PEM water electrolysis – A review, Materials Science for Energy Technologies, 2 (2019) 442-454.[2] K. Ehelebe, D. Escalera-Lopez, S. Cherevko, Limitations of aqueous model systems in the stability assessment of electrocatalysts for oxygen reactions in fuel cell and electrolyzers, Current Opinion in Electrochemistry, 29 (2021) 100832.[3] W. Wang, L. Ding, J. Li, Z. Xie, M.M. Mench, F.-Y. Zhang, An ink-free integrated dual electrode assembly for economical proton exchange membrane water electrolysis at ultrahigh current densities, Chemical Engineering Journal, 494 (2024) 153015.

Enabling 5V Solid-State Lithium Metal Batteries Using Catholyte for LiNi0.5Mn1.5O4 Spinel

Solid-state lithium metal batteries, SSLMBs, are widely sought after as the next generation battery technology due to their potential intrinsic safety and higher energy density. However, several challenges need to be addressed to achieve this goal. Previous studies have identified various challenges with the cathode electrode, including interphases, low active material contents, and limited overall ionic and electronic conductivity for high power density. [1] Additionally, there are different types of cathode materials that are currently under R&D for SSBs such as layered oxides, olivine phosphates, and spinel oxides. Among these, the spinel oxide LiNi0.5Mn1.5O4 (LNMO) has the highest voltage compared to other cathode materials, making it an attractive candidate for maximizing the energy density of active materials in solid-state batteries.However, most solid-state batteries require a catholyte,[2] solid electrolyte in the cathode electrode, to provide bulk ionic conductivity, but this, in turn, reduces energy density due to the addition of inactive materials.[3] Therefore, utilizing LNMO, a high energy density cathode, is a promising solution for solid-state batteries to compensate for this energy density loss.To ensure high voltage stability, it is crucial to have a well-designed catholyte composition that minimizes the use of solid electrolyte while ensuring excellent electronic and ionic conductivity to the cathode. In this work, we introduce a catholyte formulation that can effectively utilize LNMO and demonstrate promising cycling results with a Garnet-based solid electrolyte, having cycled over 100 times. This research opens up new possibilities for enhancing the performance of 5V solid-state lithium batteries using catholyte for the LMNO spinel cathode while maintaining high energy densities. Liang, Y., et al., Challenges, interface engineering, and processing strategies toward practical sulfide‐based all‐solid‐state lithium batteries. InfoMat, 2022. 4(5): p. e12292.Al-Salih, H., Houache, M.S.E., Baranova, E.A. and Abu-Lebdeh, Y. (2022), Composite Cathodes for Solid-State Lithium Batteries: “Catholytes” the Underrated Giants. Adv. Energy Sustainability Res., 3: 2200032.Yim, C.-H., et al., Understanding key limiting factors for the development of all-solid-state-batteries. Chemical Engineering Journal Advances, 2023. 13: p. 100436.

Dry Battery Electrode Manufacturing for Graphite Anodes: Implications on Electrochemical Properties and Cell Manufacturing

Dry Coating of Lithium-Ion Battery electrodes is widely considered as a gamechanger technology to reduce the cost, energy demand and footprint of battery Gigafactories. By now, industrialization has primarily focused on the negative electrode using graphite and as active material, notably by Tesla.[1] Yet, the full scope of the implications and advancements brought by a dry coating process for graphite anodes on cell properties and downstream manufacturing processes remains unexplored.Current dry coating technologies necessitate using a fibrillizable PTFE binder. While PTFE is very stable towards oxidation when used as a binder in Lithium-Ion Battery cathodes, a reduction of the fluoropolymer in battery anodes at low potentials < 1 V vs. Li/Li+ is reported.[2] We discuss the decomposition reaction of PTFE in graphite anodes during the formation process and the resulting irreversible consumption of Li. Our interest focuses on the decomposition mechanism of PTFE, examining the nature of the decomposition products through XPS analysis. We assess whether the reduction is quantitative and if the decomposition persists beyond the initial lithiation of graphite into subsequent cycles. We contemplate strategies to reduce the irreversible capacity loss and show that reducing the PTFE binder content while maintaining the mechanical integrity of the electrode is a promising approach to enhance the coulombic efficiency during formation.Beyond the electrochemical implications, differences in microstructural properties and the processing conditions during electrode manufacturing between a wet and a dry coated graphite anode offer opportunities for adaptions in the downstream process of Lithium-Ion Battery manufacturing. We demonstrate that the electrolyte filling time of cylindrical cells in a 4695-format is strongly influenced by the coating method and the arising differences in pore size distribution and electrode tortuosity. Also, we show that a vacuum drying of the anodes might not be needed if the electrode is dry coated instead of using water as the solvent for a slurry-based coating.[1] https://www.youtube.com/watch?v=8WPPBhqeekw[2] Y. Suh, J. K. Koo, H. Im, Y.-J. Kim, Chemical Engineering Journal 2023, 476, 146299.

Electrocatalyst Design for Carbon Dioxide Co-Reduction with Nitrate for Sustainable Synthesis of Urea

The electrochemical co-reduction of nitrate (NO3 -) and carbon dioxide (CO2) for the synthesis of urea has drawn much research focus recently because it creates value-added products from environmentally hazardous pollutants. Urea is the major ingredient of fertilizer, that is currently produced through the Bosch-Meiser process starting from ammonia (NH3) and carbon dioxide (CO2), in which ammonia is produced through the Haber-Bosch process, leading to significantly high energy consumption and CO2 emissions. Urea electrosynthesis is a complex 16e-, 12H+ transfer reaction with multiple possible by-products such as H2, CO, HCOOH, NO2 -, NH3, etc., making the electrocatalyst design toward urea selectivity a big challenge.To reliably quantify the urea produced, we present an updated method for urea quantification using the diacetylmonoxime-thiosemicarbazide (DAMO-TSC) method while excluding the interference of NO2 - by-product. We believe this method can guide the electrocatalysis community to establish an updated protocol and avoid false positive/overestimating results.We will then present a catalyst designed for urea electrosynthesis consisting of Pd nanoparticles in nanoscale proximity to atomically dispersed Fe-Nx sites on a carbon matrix (FeNC). Our group has previously presented Pd nanoparticles and FeNC materials as efficient catalysts for CO2 and NO3 - reduction respectively. Their association at the nanoscale demonstrates over 20% urea faradaic efficiency at -0.5 V (vs RHE) with 100% N-selectivity (All by-products contain nitrogen). These very promising results provide us with the baseline to elucidate the role of individual active sites on the C-N coupling mechanism. To this effect, reaction intermediates of CO2 and NO3 - co-reduction are investigated by in-situ vibrational spectroscopy (Raman, infrared). This study validates the approach of tuning electrocatalysts through mechanistic studies realizing CO2 / NO3 - co-reduction.Reference: Murphy, E., Liu, Y., Matanovic, I., Rüscher, M., Huang, Y., Ly, A., Guo, S., Zang, W., Yan, X., Martini, A., Timoshenko, J., Cuenya, B. R., Zenyuk, I. V., Pan, X., Spoerke, E. D., & Atanassov, P. Elucidating electrochemical nitrate and nitrite reduction over atomically-dispersed transition metal sites. Nat Commun 14, 4554 (2023).Guo, S., Liu, Y., Murphy, E., Ly, A., Xu, M., Matanović, I., Pan, X., & Atanassov, P. Robust palladium hydride catalyst for electrocatalytic formate formation with high CO tolerance. Applied Catalysis. B, Environmental, 316, 121659. (2022).Huang, Y., Wang, Y., Liu, Y., Ma, A., Gui, J., Zhang, C., Yu, Y., & Zhang, B. Unveiling the quantification minefield in electrocatalytic urea synthesis. Chemical Engineering Journal, 453, 139836. (2023).

Percolation Investigation of Polymer-Based Battery Electrodes and Its Influence on Capacity Utilization

Our oral presentation will offer a comprehensive exploration of the intricate dynamics governing organic radical battery electrodes, focusing on the percolation phenomena and its consequential influence on capacity utilization. Our latest investigations center around quantifying the role of conducting additives, notably the widely employed spherical SuperP® (SP), within a composite electrode based on poly(2,2,6,6-tetramethyl-4-piperinidyl-N-oxylmethacrylate) (PTMA). We recently reported a comprehensive study on the percolation investigation of SP in such composite electrodes in the Chemical Engineering Journal 2023, 477, 146882.This quantitative analysis of the conducting additive in organic battery electrodes emphasizes the critical balance required for optimal electrode composition in industrial applications. Based on the percolation theory we experimentally investigate various electrode compositions and identify a pivotal phase transition at 8 wt.% SP, which is effectively transforming the electrode's behavior from dielectric to conducting.To provide a comprehensive understanding, we incorporated a series of experimental analyses. The investigation begins with a detailed exploration of permittivities, shedding light on the dielectric properties of the composite electrode. Dielectric losses are scrutinized, providing insights into energy dissipation mechanisms within the electrode. Moreover, the characterization shows that the electrode exhibits so called epsilon-negative properties, which is commonly reported in literature for polymer/nanomaterial composites. However, a resonance type behavior of the permittivity measured at a relatively low frequency could not be assigned to any literature findings yet.Furthermore, morphological assessments through scanning electron microscopy offer a visual, qualitative validation of the established conducting percolation paths within the PTMA-based composite electrode.To the best of our knowledge, we are the first to apply distribution of relaxation times (DRT) analysis to organic radical battery electrodes, validating the hopping-type conduction mechanism for the dielectric electrodes below percolation threshold as well as assigning the conduction above percolation threshold to the SP phase.The electrochemical characterization of the percolation phase transition's impact on the electrode’s capacity utilization was investigated in both coin cells (two-electrode setup) and Swagelok cells (three-electrode setup) via galvanostatic cycling experiments. These electrochemical analyses not only validate the percolation-induced shift in behavior but also provide insights into the charge storage capabilities of several electrode compositions, which provides a basis for electrode optimization. Furthermore, the cycling experiments elucidate the electrochemical performance variations when employing two-electrode setups as opposed to three-electrode setups.Key findings underscore a direct correlation between the optimal electrode composition for enhanced capacity utilization and the observed percolation phase transition. Electrodes falling below the percolation threshold exhibit charge storage characteristics close to zero, primarily due to elevated ohmic overpotentials. In contrast, electrodes exceeding the threshold demonstrate a rapid saturation in capacity utilization, signifying the intricate interplay between conducting paths and efficient accessibility of redox centers within battery electrodes.Additionally, our findings introduce the possible application of impedance spectroscopy (IS) measurements as a preliminary electrode characterization step. This new approach not only offers valuable insights into the charge-discharge dynamics of organic radical battery electrodes but also enables general electrode composition optimization prior to laborious cell assembly and time-consuming battery cycling experiments.Furthermore, this work may be used as basis for a potential pre-quality control tool for electrodes in a high-throughput production in an industrial setting. Considering the graphical abstract, concentration changes could be identified before cell assembly. Additionally, the impact on cell performance due to the concentration changes may be estimated. By integrating IS into the production process, we envision real-time monitoring and adjustment during large-scale manufacturing processes, ensuring consistent electrodes with optimized performance. Figure 1

Advances in Redox-Electrodialysis for Energy-Efficient Desalination

Electrochemical separations have rapidly grown in recent years due to advances in functional materials as well as architecture design. By bridging the technologies between redox-based energy storage and desalination, redox-mediated electrodialysis (redox-ED) has been shown to achieve continuous desalination from brackish water to seawater, with reduced energy consumption. Here, we provide an overview the advances in redox-electrodialysis, in terms of materials design as well as electrochemical engineering. First, by replacing costly and sensitive ion-exchange membranes (IEMs) with robust nanofiltration membranes (NFs), we enable the energy-efficient desalination and removal of organic contaminants.1 NF-enabled redox-polymer ED demonstrated desalination down to potable water (<500 μS/cm) in wastewater containing organic substances, while redox-ED with IEM suffered from significant membrane fouling and slower desalination rates.Second, by combining the water-soluble redox polymers with NFs, we removed a variety of chain lengths of carboxylates and per- and polyfluorinated substances (PFAS), while preventing membrane fouling and polymer crossover into the feed solution. Finally, we discuss the application of redox-electrodialysis systems for facilitating downstream processing in biomanufacturing, through the retention of proteins and organic acids from complex food and fermentation streams. 2-4 In general, we envision redox-electrodialysis platforms to gain increased attention for both water purification and multicomponent industrial separations. References (1) Kim, N.; Elbert, J.; Kim, C.; Su, X. Redox-Copolymers for Nanofiltration-Enabled Electrodialysis. ACS Energy Letters 2023, 8 (5), 2097-2105.(2) Kim, N.; Lee, J.; Su, X. Precision Tuning of Highly Selective Polyelectrolyte Membranes for Redox‐Mediated Electrochemical Separation of Organic Acids. Advanced Functional Materials 2023, 33 (12), 2211645.(3) Kim, N.; Oh, W.; Knust, K. N.; Zazyki Galetto, F. b.; Su, X. Molecularly Selective Polymer Interfaces for Electrochemical Separations. Langmuir 2023, 39 (47), 16685-16700.(4) Kim, N.; Jeon, J.; Elbert, J.; Kim, C.; Su, X. Redox-mediated electrochemical desalination for waste valorization in dairy production. Chemical Engineering Journal 2022, 428, 131082.