bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Hydrogen on Combustion in Ammonia–Diesel Dual Fuel Engine and Demonstration of Autothermal Catalyst to Reform Ammonia Into Hydrogen
Authors: Niki Yoichi , Hirata Koichi , Kobayashi Kazuyuki , Shimizu Yuki 
Published: January 2024

Abstract
The authors conducted NH3 and diesel fuel dual fuel combustion experiments using both large and small single-cylinder diesel engines and investigated its combustibility and emission changes by adding H2. In addition, the small engine was operated by supplying reformed gas containing H2, which was produced using a device to reform NH3 into H2. Co-combustion of NH3 and diesel fuel with large and small single-cylinder engines showed similar trends in the change of emissions. In particular, N2O emissions tended to decrease when the NH3 energy fraction was higher in the cases of the large engine. The combustion-assisting effect of H2 was obtained when H2 was mixed into the charge air of NH3/diesel dual fuel mode with the large and small single-cylinder engines. The addition of H2 resulted in a reduction in unburned NH3 and a change in N2O emissions. Reduction in N2O emissions was achieved by increasing the amount of supply H2, particularly for the large engine. The small engine was operated by supplying reformed gas. This allowed unburned NH3 to drastically decrease. It was also found that N2O emission can be generated when NH3 remains in the reformed gas. The NH3 reforming system has achieved the target H2 flow rate, and the effectiveness of the proposed reforming system has been demonstrated. This research provided valuable insights for the design of an NH3 reforming system suitable for marine engines.
The Effects of Intake Throttling With Hot and Cold EGR in a CNG/Diesel Dual Fuel Engine
Authors: Tripathy Srinibas , Sarangi Asish Kumar , Patel Vimal Kumar , Sreedhara Sheshadri 
Published: January 2024

Abstract
Compressed natural gas (CNG)-diesel dual fuel engines produce lower emissions of nitrogen oxides (NOx) and particulate matter over conventional diesel engines. However, their major limitations are poor combustion stability at low and intermediate loads with high total hydrocarbon (THC) and carbon monoxide (CO) emissions. The limitations of poor combustion stability and high combustion by-products (THC and CO) emissions are exacerbated at high engine speeds. In this study, the authors attempt to reduce the THC and CO emissions at an intermediate load, corresponding to 6 bar gross indicated mean effective pressure (IMEP), at two engine speeds of 1500 rpm and 2800 rpm through intake throttling and using hot and cold exhaust gas recirculation (EGR) strategies in a CNG/diesel dual fuel engine. Experimental investigations are carried out at a 70% premixed ratio for the dual fuel engine. The results show that intake throttling has the potential to reduce THC and CO emissions by ∼37% and 15% at 1500 rpm and by ∼22% and 10% at 2800 rpm compared to the baseline dual fuel operation. However, NOx emissions increased as a trade-off. Further, implementing hot and cold EGR strategies to intake throttling, a significant reduction in NOx (∼72–78%) emission is observed, while THC and CO reductions are marginal at high speed. It is found that throttling the intake air in combination with hot EGR is more effective in reducing THC, CO and NOx emissions as compared to throttling with cold EGR strategy, while maintaining a similar power density as the baseline dual fuel engine.
Effect of Gas Composition on the Oxidation of Gas Component Emissions of a Dual-Fuel Diesel-Natural Gas Engine at Low Load Conditions
Authors: Ulishney Christopher , Dumitrescu Cosmin E. 
Published: January 2024

Abstract
This study investigated engine efficiency and emissions at low load dual-fuel diesel-natural gas (NG) engine operation, which has a higher sensitivity to NG composition. 40% of the diesel fuel energy was partially substituted with gas blends containing methane, ethane, and propane. NG was delivered inside the intake manifold by low-pressure gas injectors. Results showed that blends with ethane and propane reduced the net global warming potential by ∼5% compared to pure methane, at constant fuel energy content, with the reduction primarily linked to differences in exhaust hydrocarbon composition. No statistically significant impact on the brake mean effective pressure was found. The changes in gas composition created up to a 10% increase in carbon monoxide concentrations in the exhaust, as an earlier combustion phasing increased the fraction of premixed NG trapped in the combustion chamber’s crevices. Also, a 20% reduction in specific methane, ethane, and propane emissions was achieved for mixtures with 10% propane addition. Propane addition enhanced combustion efficiency and methane oxidation compared to ethane addition. The reduction of methane, ethane, and propane mass fraction in the exhaust correlated with their auto-ignition temperatures and laminar flame speeds, with ethane and propane oxidizing significantly better than methane. Finally, the results imply the emission composition of diesel-NG dual-fuel operation was more sensitive than engine power output to the change in NG fuel composition.
Spark Plasma Stretching and Flame Propagation via High Frequency Pulsed Current Management
Authors: Wang Linyan , Yu Xiao , Zheng Ming 
Published: January 2024

Abstract
The performance and advancement of ignition systems become more important than ever to further improve the fuel efficiency and exhaust emissions of modern engines. The ignition processes of modern engines are often subjected to a fuel-lean or inert-gas-diluted mixture of considerably high density and strong air motion. Bulk gas movements in the vicinity of the spark gap, such as crossflows, can stretch the plasma channel across the spark gap, which enhances the total discharge energy compared with quiescent conditions. A higher discharge current has been proven to be an effective way to prolong the spark plasma stretching. However, high discharge current (boosted up to 3A) increases the power consumption of the ignition systems, affecting system durability and energy efficiency. Besides, the continuous high current cause rapid spark electrode erosion, which affects the durability of the spark plug. In this work, a novel high-frequency pulsed current management strategy is proposed to improve plasma stretching and energy release, while decreasing the total energy consumption of the ignition system. Within precise control of discharge duration, a high-frequency pulsed discharge strategy is achieved without interfering with the plasma stretching process. The characteristics of the plasma channel are recorded via both electrical and optical measurements.
Validation of a 1D Modeling Technique to Predict Performance of Turbocharged Engines Including a Double Scroll Turbine With Connection Valve
Authors: Avola Calogero , Suzuki Tetsu , May Ian , Tafreshi Ali , Tanigaki Michihiko , Williams Carnell , Briscoe Ken , Gray Bill , Trudeau Jon , Iosifidis Georgios , Durbiano Loic , Delavan Matt 
Published: January 2024

Abstract
In the engine exhaust manifold, pressure pulses from several cylinders can interfere with exhaust phases of two different cylinders taking place simultaneously. In four-cylinder engines, interference between exhaust pulses can be reduced by double scroll (DS) turbines. These can ensure pulse separation and improve performance at low engine speeds where the exhaust pulsing effect is more predominant. However, high speed power of the engine can be limited by the increased restriction caused by the DS turbine, in comparison to a single scroll solution. Therefore, IHI developed a regulated Scroll Connection Valve (SCV) to allow increased connection area between scrolls, reducing the restriction at high engine speeds.
Prediction of performance using 1D models can be challenging under open SCV conditions. The opening of the SCV simultaneously affects the connection between scrolls and the wastegate ratio, influencing turbine performance. This paper shows an approach to overcome the modeling challenges of DS turbines with SCV, using additional data retrieved from gasstand testing and 3D CFD simulations to update efficiency and discharge coefficient, respectively. The validation of the 1D model is performed on a four-cylinder gasoline engine from General Motors with an IHI turbocharger, equipped with a DS turbine and SCV. The model predicts performance at full load with a maximum error of 4% in BSFC at 2500rpm. No error was recorded by the model prediction during the time-to-torque at 1500rpm, showing correct prediction when SCV is kept fully closed. Finally, while keeping the valve fully open, base boost pressure was underpredicted by about 5%.
Investigation of the Laminar Burning Velocity and Exhaust Characteristics of Methane-Ammonia-Hydrogen Ternary Blends
Authors: Nasim Md Nayer , Nawaz Behlol , Das Shubhra Kanti , Landis Joshua , Shaalan Amr , Van Dam Noah , Trelles Juan Pablo , Assanis Dimitris , Mack J. Hunter 
Published: January 2024

Abstract
Even though usage of hydrogen (H2) in the energy sector has gained a considerable amount of traction over the last decade, its high flame speed restricts its feasibility as a drop-in replacement for existing fuels in applications such as internal combustion engines and gas turbines. In order to address some potential issues, ammonia (NH3) can be used in conjunction with hydrogen, as its slow reaction kinetics offset that of H2 without compromising decarbonization efforts. However, simply replacing natural gas (primarily methane, CH4) with hydrogen/ammonia blends is not trivial due to compatibility issues associated with bulk combustion characteristics. In this study, methane-ammonia-hydrogen ternary blends are comprehensively investigated in terms of laminar burning velocity, flame morphology, stability, and emissions in order to understand transitional regimes between fossil-based approaches and carbon-free alternatives. This work presents the analysis of the combustion properties of different ammonia/methane/hydrogen blends at varied equivalence ratios in an optically accessible constant volume combustion chamber (CVCC) coupled with Z-type schlieren visualization. The emissions from each experimental trial were analyzed using a Fourier Transform Infrared (FTIR) Spectroscopy system for detailed speciation. Furthermore, a computational approach was implemented to validate the laminar burning velocity results using an established mechanism already tested for ternary blends.
Study of NOx Formation at Lean Conditions in a Prechamber-Ignited Two-Stroke Natural Gas Engine
Authors: Nowlin Jacob , Patterson Mark , Jacobs Timothy J. 
Published: January 2024

Abstract
A computational fluid dynamics study of a large-bore, two-stroke, integral compressor engine is conducted. The engine under study operates on natural gas and uses a prechamber for ignition. The purpose of this work is to ascertain how property variations in the prechamber jet affect NOx formation in the main combustion chamber. Several testing suites were performed using a CFD model of a Cooper-Bessemer GMV four-cylinder engine. The chemical composition and temperature of the prechamber jet were manually modified for each simulation. NO emissions were found to be more sensitive to increases in the jet temperature than decreases in the jet temperature. NO2 emissions were largely insensitive to any jet temperature modification. Jet composition was modified to represent discrete prechamber fuel-air ratios. A non-monotonic relationship exists between jet composition and NOx formation. In general, the optimal balance among NOx, residual CH4, and CO was found for simulations using a prechamber equivalence ratio slightly rich of stoichiometric. NO tended to form relatively early in the cycle in areas surrounding the PCC jet. Later in the cycle, NO collected around the perimeter of the cylinder. The extended Zeldovich and N2O mechanisms were the highest contributors to NO formation. NO2 formed relatively late in the cycle in areas of high NO concentration.
Experimental Demonstration of a High-Power Density Electric Generator
Authors: Gore Matthew , Nonavinakere Vinod Kaushik , Fang Tiegang 
Published: January 2024

Abstract
Electric vehicles (EV) are an increasingly common alternative to gasoline vehicles. However, most have significantly shorter drivable ranges than IC vehicles and require a long waiting period to recharge. Further, the lack of robust charging networks severely limits the viability of EVs in certain regions of any country. Range extenders have been proven to be one of the most attractive options to address EVs’ limited drivable range and range anxiety. Currently, the market for range extenders exists in two classes: a 50kW type, which can be heavy, bulky, and immovably fixed to the vehicle, or a 5kW type which can be too weak to provide any usable range to the EV in a reasonable amount of time. The goal of this work is to develop and showcase a high power density generator, which may be used as a range extender, constructed from commercially available components configured to be easily transportable while having the capacity to rapidly charge an EV battery. The device discussed in this work includes a two-stroke single-cylinder gasoline engine and a compact permanent magnet brushless dynamo as commonly found on hybrid vehicles that are capable of producing up to 15kW of power. The advantages of this combination include compactness, simplicity, lower weight, and lower thermal and mechanical loads. This paper discusses the design and experimental development of such a portable high-power-density power generator. The performance and emissions characteristic of the generator is investigated at varying loads and compared to currently available systems. During preliminary experiments, the power generator produced 8.8kW while having a dry weight of just 22kg. Future design recommendations for use of alternative/E-fuels are also explored.
Novel Approaches to Improve the Performance of a Single Cylinder Engine by Turbocharging, Supercharging and Turbo-Compounding – A Comparative Study
Authors: Jayaraman Ramkumar , Krishnasamy Anand , A. Ramesh 
Published: January 2024

Abstract
Designers find it extremely challenging to enhance the performance of single-cylinder engines. Since the exhaust flow is intermittent, single-cylinder engines available in the mass market are seldom turbocharged despite turbocharging being a staple technology in other multi-cylinder engines. Hence, almost one-third of the fuel energy is lost in the exhaust, reducing the performance of the single-cylinder engine. In the current work, the authors explore novel approaches to charge a single-cylinder diesel engine and extract power from the pulsated exhaust flow. Also, the authors compare the novel approaches. In the first approach, an exhaust plenum was employed to mitigate the exhaust flow pulsations to turbocharge the single-cylinder engine. In the second approach, a supercharger was employed to charge the engine and an impulse turbine was compounded to extract energy from the pulsated exhaust flow. One-dimensional simulation results indicated that turbocharging and supercharging with impulse turbine compounding significantly improved engine performance. With turbocharging, the brake power output from the engine increased by 26.3%, the airflow rate increased by 71%, and brake thermal efficiency increased by 1.5%. With supercharging and impulse turbine compounding, the brake power output increased by 41.8%, the airflow rate increased by 62%, and the brake thermal efficiency increased by 5.3%. Both novel approaches improved the performance of the single-cylinder engine significantly. The novel supercharging and impulse turbo-compounding approach provided superior results compared to the novel turbocharging approach. Thus, a comparative study of turbocharging, supercharging, and turbo-compounding was carried out and detailed in the present work.
48V High Power Hybrid Architecture for MHD Off-Road Applications
Authors: Yan Ziming , Peters Nathan , De Salis Rupert , Bunce Michael 
Published: January 2024

Abstract
The demand for decarbonization across all automotive industries is growing, and therefore improving fuel economy and reducing emissions have become top priorities in powertrain technology development. Although battery and fuel cell electric powertrains can be widely deployed to aid decarbonization in many sectors, medium- and heavy-duty (MHD) off-road applications present challenges that are difficult to address with these powertrain approaches. For example, off-road applications require high power ratings, low dwell/refuel times, and robustness to extreme environmental conditions. Additionally, the efficiency of traditional engine-based powertrains for these applications is limited due to the peak load requirement and highly transient operation. Hybridization for heavy-duty off-road powertrains is a viable de-carbonization pathway, replacing or supplementing engine operation with tailored electrification solutions that can also enable the use of low life-cycle carbon fuels that have problems covering the full operating map.
In this study, a novel high-power low-voltage (HPLV) hybrid architecture is employed for medium and heavy-duty off-road applications, featuring a downsized engine, an integrated electric motor, and an energy storage solution that utilizes ultracapacitors for high energy capacity and rapid energy discharge. A modeling approach is presented, as well as a system analysis that compares off-road vehicles with powertrains using internal combustion engines, high-voltage hybrid systems with batteries, and the low-voltage hybrid system investigated here. The analysis shows that, among all available electrification options for MHD off-road vehicles, the low-voltage system with ultracapacitors provides the best synergy with the ICE powertrain, both technologically and economically. Furthermore, the results demonstrate a 17% reduction in powertrain weight through engine downsizing and a payback period of 33 months compared to the conventional diesel powertrain vehicle. Additional simulation results with a real-world mission profile indicate a fuel economy improvement and greenhouse gas emissions reduction of up to 15.5%, and a decrease in criteria emissions of up to 15% are possible, illustrating the emissions benefits of the HPLV hybrid system.
Non-invasive high-frequency oscillatory ventilation (NHFOV) versus nasal continuous positive airway pressure (NCPAP) for preterm infants: a systematic review and meta-analysis
Authors: Wang Kaixu , Yue Guang , Gao Shuqiang , Li Fang , Ju Rong 
Published: January 2024

ObjectiveTo compare the efficacy and safety of non-invasive high-frequency oscillatory ventilation (NHFOV) and nasal continuous positive airway pressure (NCPAP) in preterm infants.DesignThe study conducted a comprehensive analysis across three databases, namely EMBASE, MEDLINE and Cochrane Central, to identify randomised controlled trials comparing NHFOV and NCPAP. Statistical analysis was performed using Review Manager V.5.3 software.Main outcomes measuresThe primary outcomes of the study were the intubation or reintubation rate in the NHFOV and NCPAP groups. Additionally, secondary outcomes included the partial pressure of carbon dioxide levels and major complications associated with non-invasive respiratory support ventilation.ResultsTen randomised controlled studies, involving 2031 preterm infants, were included in this meta-analysis. When compared with NCPAP, NHFOV demonstrated a significant reduction in the intubation or reintubation rate (p<0.01, relative risk=0.45, 95% CI 0.37 to 0.55), and there was no statistical difference in related complications.ConclusionIn preterm infants, NHFOV appears to be an effective intervention for decreasing the intubation or reintubation rate compared with NCPAP, with no increase in associated complications.Trial registration numberCRD42023403968.
Flow diverter stents for endovascular treatment of aneurysms: a comparative study of efficacy and safety between FREDX and FRED
Authors: Guimaraens Leopoldo , Saldaña Jesus , Vivas Elio , Cifuentes Sebastián , Balaguer Ernest , Mon Dunia , Macias-Gómez Adrià , Ois Angel , Guisado-Alonso Daniel , Cuadrado-Godia Elisa , Jiménez-Balado Joan 
Published: January 2024

BackgroundThe FRED X flow diverter (FREDX), as the second generation in the FRED series, aims to improve the treatment of cerebral aneurysms. This study compares the efficacy and safety of FREDX with its predecessor, FRED.MethodsThis prospective registry included patients treated with FRED and FREDX devices. Efficacy was assessed using digital subtraction angiography with 3D volumetric reconstruction at immediate and 1 year follow-ups. Safety was evaluated by recording complications, analyzed through univariate contrasts, generalized mixed models, and Bayesian network analyses.ResultsWe treated 287 patients with 385 aneurysms, with 77.9% receiving FRED and 22.1% FREDX. The median age was 55 years (IQR 47–65) and 78.4% were women. The FREDX group showed a higher prevalence of saccular-like aneurysms (70.6% vs 52.7%, P=0.012) and a higher rate of complete occlusion compared with FRED interventions (79.4% vs 59.3%, P=0.022). After adjusting for confounders, these differences represented a 3.04-fold increased likelihood (95% CI 1.44 to 6.41, P=0.003) of achieving complete occlusion at 1 year with FREDX interventions. Regarding safety, two (3.5%) complications (both non-symptomatic) were observed in the FREDX group and 23 (10.4%) in the FRED group (P=0.166). Bayesian network analysis suggested a trend towards fewer complications for FREDX, with a median reduction of 5.5% in the posterior distribution of the prevalence of complications compared with FRED interventions.ConclusionsThe FREDX device shows improved complete occlusion rates at 1 year compared with the FRED device while maintaining a favourable safety profile, indicating its potential advantage in the treatment of cerebral aneurysms.
Abstract A027: Aberrant glycosylation in mPDAC cells is associated with increased recruitment of immunosuppressive cells
Authors: Brookens Shawna , Degaramo David , Wilson Kiesha , Obregon Wilder Condori , Nagarkatti Mitzi , Posey Avery 
Published: January 2024

Abstract
Tumor associated-glycan Tn antigen (aGalNAc-a-O-Ser/Thr) is associated with poor prognosis in various solid tumors. However, the mechanisms that Tn antigen promotes tumorigenesis is incompletely understood. Here, we generated Tn antigen-expressing murine pancreatic ductal adenocarcinoma (mPDAC) tumor cell lines through CRISPR/Cas9-mediated knockout of the C1galt1c1 gene. Tn antigen expressing mPDAC cell lines exhibited increased in vitro proliferation and migration compared to parental controls. RNA sequencing revealed that loss of C1galt1c1 in mPDAC cells correlated with increased expression of myeloid recruitment and differentiation genes, IL34 and Lif. Additionally, C1galt1c1 knockout mPDAC cells implanted into mice led to accelerated tumor growth and increased tumor infiltration of myeloid-derived suppressor cells and neutrophils as determined by flow cytometry and scRNAseq. Interestingly, surface expression of a binding partner of Tn antigen, macrophage galactose N-acetyl galactosamine specific lectin 2 (Mgl2), was decreased in the infiltrate of C1galt1c1 knockout tumors suggesting a role for the Mgl2-Tn interaction in tumor progression. Together, our data indicate that expression of Tn antigen on tumor cells promotes an immunosuppressive microenvironment in mPDAC.
Citation Format: Shawna Brookens, David Degaramo, Kiesha Wilson, Wilder Condori Obregon, Mitzi Nagarkatti, Avery Posey Jr.. Aberrant glycosylation in mPDAC cells is associated with increased recruitment of immunosuppressive cells [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr A027.