Conversion Point Research Articles

Parents' experiences of psychotherapeutic support on the neonatal unit: A mixed methods systematic review to inform intervention development for a multicultural population.

Parents of infants admitted to neonatal intensive care require support to minimize the impact on their mental health and to encourage engagement with their infants to support infant neurodevelopment. Many interventions aim to address this need, but there is a lack of research considering the accessibility of these for a multicultural population. To systematically identify sources of psychotherapeutic support available for parents with infants admitted to neonatal care (NNU, neonatal intensive care unit [NICU] and special care units), assess their accessibility and acceptability and identify challenges and facilitators. Six electronic databases with no restrictions on language or date were used to identify relevant studies following Preferred Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. Publications were included in the review if they reviewed parent experience of an intervention actively in place to support parent experience during the neonatal unit stay. Any studies where the intervention's primary aim was infant focused, such as developmental care, were excluded. All publications were quality-assessed using quality appraisal tools appropriate for their design type. Data were extracted line by line using Sekhon et al.'s theoretical acceptability framework and questionnaire. A total of 3309 studies were found, of which 36 studies met the inclusion criteria. Included studies were published worldwide between 2000 and 2023 and explored 15 different interventions. Challenges for parental engagement were due to preconceived ideas about intervention requirements and parents' ability to participate in them. Timely information and providers' experience in delivering the intervention were reported to support engagement and as being valuable for enhancing participant knowledge. The emotional content of interventions was found to be challenging by parents across most studies. This was prominent in interventions designed to be carried out in a group format and where keepsakes were created. However, the value of these interventions was in reducing parents' feelings of isolation through increased social support and providing a starting point for conversations with wider family and friends about the family's neonatal experience. Participant demographics were poorly reported, with only two studies taking into consideration the ethicality of the intervention. Poor reporting of participant demographics, and a focus on mothers as participants, means findings are not transferrable to the wider population of parents in neonatal units. Future studies should consider how to ensure that research and interventions are accessible to multicultural populations to improve the understanding of the acceptability of interventions. Better knowledge of neonates and the NNU setting amongst intervention providers could increase the accessibility of psychotherapeutic support for parents. Training for providers on how to manage sensitive conversations may also be beneficial to support parents during interventions. The impact of neonatal admission on parental mental health is increasingly recognized and reported. Interventions have been developed to reduce the negative impact on the mental health of parents. There continue to be significant health inequalities as a result of many services not taking into account the acceptability and accessibility of interventions in this setting for their multicultural populations. This review highlights the need for better reporting of participant demographics in research and the inclusion of those seldom heard to ensure interventions are culturally, religiously and linguistically appropriate for multicultural populations.

Development of a novel renewable energy-based integrated system coupling biomass and H2S sources for clean hydrogen production

The present work aims to develop a novel integrated energy system to produce clean hydrogen, power, and biochar. The Palmaria palmata, a type of seaweed, and hydrogen sulfide from the industrial gaseous waste streams are taken as potential feedstock. A combined thermochemical approach is employed for the processing of both feedstocks. For clean hydrogen production, the zinc sulfide thermochemical cycle is employed. Both stoichiometric and non-stoichiometric equilibrium-based models of the proposed plant design are developed in the Aspen Plus software, and a comprehensive thermodynamic analysis of the system is also performed by evaluating energy and exergy efficiencies. The study further explores the modeling, simulation, and parametric analyses of various subsections to enhance the hydrogen and biochar production rate. The parametric analyses show that the first step of the thermochemical cycle (sulfurization reaction) follows stoichiometric pathway and the ZnO to H2S ratio of 1 represents the optimal point for reactant conversion. On the other hand, the second step of the thermochemical cycle (regeneration reaction) does not follow a stoichiometric pathway and ZnS conversion of 12.87% is achieved at a high temperature of 1400oC. It is found that a hydrogen production rate of 0.71 mol/s is achieved with the introduction of 0.27 mol/s of H2S. The energy and exergy efficiencies of the zinc sulfide thermochemical cycle are found to be 65.23% and 35.58% respectively. A biochar production rate of 0.024 kg/s is obtained with the Palmaria palmata fed rate of 0.097 kg/s. The Palmaria to biochar energy and exergy efficiencies are found to be 55.43% and 45.91% respectively. The overall energy and exergy efficiencies of the proposed plant are determined to be 72.88% and 50.03% respectively.

Relationships Between Upper-Plate Structure, Mantle Wedge Melting, and Fore-Arc Sliver Transport in the Nicaraguan Subduction Zone

Abstract This study images the base of the upper-plate lithosphere in the Nicaraguan subduction zone using common conversion point stacking of Sp phases and explores the relationships between deep upper-plate structure, subduction zone melting processes, and the arc-parallel transport of the Central American fore-arc sliver. We observe the negative velocity gradient associated with the upper-plate lithosphere–asthenosphere boundary in the Nicaraguan back-arc at depths of 60–80 km. However, the amplitude of the lithosphere–asthenosphere velocity gradient diminishes beneath the arc, consistent with a reduction in the shear-wave velocity of the deep upper-plate lithosphere. This zone lies above mantle wedge velocity anomalies which indicate upward-migrating partial melt, suggesting that ascending melt has altered and weakened the lithospheric mantle of the upper plate. In northwestern Nicaragua, the boundary of the Central American fore-arc sliver and the Caribbean plate, which is marked by a northeast decrease in geodetically measured arc-parallel surface velocities, lies above the northeast increase in the amplitude and localization of the lithosphere–asthenosphere velocity gradient. This correlation indicates that the kinematic margin of the Central American fore-arc sliver corresponds to a structural boundary that extends throughout the upper plate, and that is influenced by melt ascending from the mantle wedge.

Using scalable vector graphics in medieval Latin palaeography: new approaches, new conversations

Abstract The use of scalable vector graphics (SVG) in the study of pre-modern handwriting (palaeography) to date has been extremely limited, especially amongst scholars of the medieval Latin West and its manuscript culture(s). Informed by the author’s experience of using vector graphics for over a decade in researching and teaching medieval Latin palaeography in UK and EU Higher Education, this short article offers a starting point for further conversation. Following a general introduction and a concise survey of current practice, it discusses some basic SVG editing tools and exemplifies the utility of their application in three key areas of palaeographic study (tracing, analysis, and visualization) before highlighting, by way of conclusion, potential avenues of future development with the aim of enabling and encouraging colleagues to make greater use of SVG in their research and teaching.

Wetland photography, encounters and values

Between 2016 and 2019 I embarked on a photo-essay of wetlands in English Lowlands as part of the UKRI funded project WetlandLIFE. This was a personal exploration of the sense of place of wetlands as experienced through photography. The aim was to create a collection of images around which the values of wetlands could be considered. Over 2000 photographs were taken and 32 images formed the final collection. Thirteen photographs and two photo-compilations are presented in this paper alongside reflections on the contribution of arts-based research and photography to encountering nature and creating conversations about human/nature relations. The photographs are thematically presented in six categories reflecting different aspects of my wetland experiences, these are: Authority; Memory; Work and Leisure; Creatures; Texture and Movement; Vistas (expansive and enclosed). The photographs illustrate ways society and nature are intertwined and provide a departure point for conversations about wetlands as socio-natural places.

Evidence of low velocity layers at the top and bottom of the Mantle Transition Zone (MTZ) below the Uttarakhand Himalaya, India

The Mantle Transition Zone (MTZ) beneath the Uttarakhand Himalaya has been modelled using Common Conversion Point (CCP) stacking and depth-migration of radial P-receiver functions. In the Uttarakhand Himalaya region, the depths of the 410-km discontinuity (d410) and the 660-km discontinuity (d660) are estimated to be approximately 406 ± 8 km and 659 ± 10 km, respectively. Additionally, the thickness of the mantle transition zone (MTZ) is modelled to be 255 ± 7 km. The average arrival times for d410 and d660 conversions are (44.47 ± 1.33) s and (71.08 ± 1.29) s, respectively, indicating an undisturbed slightly deeper d410 and a deformed noticeably deeper d660 in the area. The model identifies the characteristics of the d410 and d660 mantle discontinuities beneath the Lesser Himalayan region, revealing a thickening of the MTZ towards northeast, which could be due to gradual cooling or thickening of the Indian lithosphere towards its northern limit. We simulate a low-velocity layer (perhaps partially molten) above the d410 discontinuity at depths of 350 to 385 km, indicating the presence of a hydrated MTZ beneath the area. We also interpret a negative phase at d660 as a low-velocity layer between 590 and 640 km depths, which could be attributed to the accumulation of old subducted oceanic materials or increased water content at the bottom of the MTZ. Our results suggest the presence of residues from paleo-subducted lithospheric slabs in and below the mantle transition zone underlying the Uttarakhand Himalayas.

The recent progress of single-atom catalysts on amorphous substrates for electrocatalysis

Single-atom catalysts (SACs) have emerged as a focal point in energy catalytic conversion due to their remarkable atomic efficiency and catalytic performance. The challenge lies in efficiently anchoring active sites on a specific substrate to prevent agglomeration, maximizing their effectiveness. Substrate characteristics play a pivotal role in shaping the catalytic performance of SACs, influencing the dispersion and stability of single atoms. In recent years, amorphous materials have gained attention as substrates due to their unique surface structure and abundance of unsaturated coordination sites, offering an ideal platform for capturing and anchoring single atoms effectively, thus enhancing catalytic activity. To clarify the interaction between single atoms and amorphous substrates, this review outlines amorphization methods, the mechanism of single-atom anchoring and the characterization methods of amorphous SACs. Subsequently, it summarizes the physical properties and electrocatalytic mechanisms of amorphous materials. Then, interactions between single atoms and amorphous substrates are categorized and summarized. Finally, the paper consolidates the research progress of amorphous SACs and outlines future development prospects. By exploring the synergistic relationship between single atoms and amorphous substrates, this review aims to deepen the understanding of their interaction mechanisms, thereby propelling advancements in SACs for energy catalytic conversion.

Fine Crust‐Mantle Structure of the Major Tectonic Boundaries Between the North China Craton and Central Asian Orogenic Belt Revealed From Rayleigh Wave Phase Velocities and Receiver Functions

AbstractThe Tanlu Fault Zone (TLFZ) and Chifeng‐Kaiyuan Fault (CKF) serve as tectonic boundaries between the North China Craton (NCC) and the Central Asian Orogenic Belt (CAOB). Clarifying the refined structure of these tectonic boundaries is crucial for understanding the relationships between the tectonic units and the heterogeneity in the destruction of the NCC. In this study, two linear seismic arrays were deployed across these tectonic boundaries. Based on the phase velocity dispersion and receiver functions extracted from the seismic arrays, the Hamiltonian Monte Carlo algorithm was employed for the joint inversion of the S‐wave velocity (Vs) in the crust and uppermost mantle. The Vs model was then used to correct the time differences in common conversion point (CCP) stacking. The CCP stacking results indicate that the boundary faults TLFZ and CKF are both whole‐crustal faults that separate the NCC and CAOB. The Vs structure showed a significant low‐velocity anomaly in the mantle beneath the NCC, with intense seismic activity within the crust. This suggests that the NCC was affected by the subduction of the Western Pacific, leading to crustal and mantle destruction. In contrast, the CAOB exhibited a clear high‐velocity anomaly with relatively stable crustal structures. We believe that the NCC and CAOB have undergone structural modification and destruction due to the closure of the Paleo‐Asian Ocean and the activities of the TLFZ since the Late Mesozoic. During the Cenozoic, the region east of the TLFZ experienced more significant destruction in the NCC than the other adjacent tectonic units.

American Ginseng Slice Drying and Optimization: Effect of Different Drying Methods on Drying Kinetics and Physicochemical Properties

This study compared four drying methods, namely hot-air and vacuum combined drying (HAVCD), hot-air drying (HAD), vacuum drying (VD), and vacuum freeze-drying (VFD), with the aim to select a high-quality and efficient drying method to dry American ginseng slices. Drying kinetics and various physicochemical properties, such as color, rehydration ratio, total ginsenoside content, total ginsenoside residual rate, hardness, and microstructure were explored. An improved multi-indicator test formula method was used to score the experimental results quantitatively. HAVCD resulted in comprehensive advantages, with the highest product score for the dried American ginseng slices. Therefore, HAVCD was subjected to a response surface methodology (RSM) analysis and process optimization. The interaction of hot-air temperature and vacuum temperature on the comprehensive score of American ginseng drying was highly significant (p < 0.01). The optimized and validated process parameters obtained were a hot-air temperature of 57 °C, a vacuum temperature of 54 °C, and a moisture content at the conversion point of 39% (wet basis). Under these conditions, the best drying time was 170 min; the total ginsenoside content was 2.3 mg/100 g; the L* value was 91.68; the rehydration ratio was 3.10; and the comprehensive score was 96.77. The findings of this work indicated HAVCD as a promising drying method for American ginseng slices, considering the drying time and dried-product quality attributes.

Unlocking biosolid pyrolysis: Towards tailored biochar with different surface properties

To develop a thorough understanding of the thermal decomposition process of biosolids and the qualities of biosolid-derived biochar, this study performs a thermogravimetric analysis (TGA) of biosolids and examines the properties of biosolid-derived biochar produced from varying temperatures of pyrolysis. The pyrolysis of biosolid is conducted under varying heating rates (10, 15, 20 and 25 °C/min) until reaching the maximum temperature of 900 °C. The kinetic triplet (kinetic model, activation energy, and frequency factor) at the corresponding conversion point is determined by analysing the TGA results of the biosolids. The thermal degradation of hydrated compounds shows activation energies ranging from 80 to 100 kJ/mol, whereas the thermal decomposition of organic matter in biosolids exhibits activation energies ranging from 120 to 497 kJ/mol. As the temperature increases, the thermal reactions transition from simple surface reactions with frequency factors below 109 s−1 to more complex reactions with frequency factors above 109 s−1. The distributed activation energy model (DAEM) is established using the approximated temperature function and the activation energy distribution functions. The DAEM shows the mean activation energies of 93–128 kJ/mol, 279–287 kJ/mol and 359–377 kJ/mol for activation energy distribution peaks. The standard deviations of the mean activation energies are 30–64 kJ/mol, 23–30 kJ/mol and 23–41 kJ/mol, respectively. As the pyrolysis temperature is raised from 700 °C to 900 °C, both the specific surface area and micropore volume of biosolid-derived biochar increase, from 48.25 m2/g to 65.74 m2/g and 0.0313 cm3/g to 0.0369 cm3/g, respectively. The findings of this study demonstrate biosolid pyrolysis kinetics, which is essential for establishing a pyrolysis facility for biosolid management and producing biosolid-derived biochar with varying qualities.

Описание и исследование химического взаимодействия в системе Li+,Na+||F-,Cl-,Вг

The use of melts in various fields of industry and scientific research is based on the study of the properties of melts and the chemical processes occurring in them. In modern engineering and technology, a significant number of processes are associated with the use of mixtures of lithium and sodium halides as mixtures that accumulate heat, as electrolytes for medium-temperature chemical current sources. Therefore, the interest in the study of systems involving such systems is continuously increasing. The paper calculates the thermal effects of exchange reactions and Gibbs energy in ternary reciprocal systems of a quaternary reciprocal system Li+,Na+||F-,Cl-,Br-, as well as for a mixture corresponding to the central point of the conversion line. The conversion line is obtained as a result of the intersection of unstable and stable triangles. In accordance with the calculation data, it is shown that the conversion lines in the skeleton of the compositions intersect at the conversion point K3 with the maximum thermal effect of the reaction equal to the sum of the thermal effects of the reactions (as well as the Gibbs energies) for mixtures corresponding to the conversion points K1 and K2.To confirm the stability of the LiF-NaCl-NaBr triangle linking the stable tetrahedron LiF-NaCl-NaBr-NaF and the stable pentatope LiF-LiCl-LiBr-NaCl-NaBr, the interaction of the initial powder mixture of 50 mol % NaF+25 mol.% LiCl+25 mol.% LiBr has been studied by thermogravimetry. The phase transition temperatures are assigned to the heating curve of the mixture. When heated at a rate of 20 K/min, the exothermic effect begins at 463 oC and ends at 504 оC. For a stable triangle, a melt crystallization scheme of the composition of the central point of the conversion line is shown. Stable crystallizing phases have been confirmed by X-ray phase analysis.

Re-imagining higher education futures

This workshop is intended for those who have an interest in speculative methods, storytelling and the future of networked learning in universities. The workshop will use a set of new speculative scenarios for the future of higher education teaching. The scenarios were developed in 2022 to work as a provocation and starting point for new conversations about the future of our universities and the teaching we do through them. They aim to unsettle assumed futures and support us to imagine new, desirable ones. They are told from a particular time and place, and speak to present concerns and hopes. Each scenario is accompanied by a piece of microfiction which aims to convey something of what of what our imagined futures might look and feel like. It will be run by Sian Bayne and Jen Ross.

Imaging the Sedimentary and Crustal Structure of the Luoyang Basin, Central China, Using a Dense Nodal Seismic Array

Abstract The Luoyang basin lies in the southern margin of the North China block, separating the trans-North China orogen to the north and the Qinling-Dabie orogen to the south. Determining how the basin formed is important for understanding the history of the North China block and its evolution during the Mesozoic and Cenozoic times. Based on the teleseismic data recorded by a dense nodal seismic array, we used the receiver function method to image the sedimentary and crustal structures in the Luoyang basin. Common conversion point stacking images show that the Moho is at a depth of ∼35 km on the south and west sides and slightly uplifted to ∼30 km below the northeastern basin. Two sets of P-to-S conversions are imaged in the shallow crust, separating the near-surface sediments into consolidated, semiconsolidated, and unconsolidated layers. The top of the consolidated sedimentary layer is close to the surface at the southern basin and present at a depth of ∼2 km beneath the central basin, then deepens to a depth of ∼3 km below the northern basin. The discontinuous interface in the sediments indicates that the sedimentary layer was truncated by some blind north-dipping normal faults. The northeastward thinning crust, thickening sedimentary layers, and dipping normal faults together indicate that the Luoyang basin evolved in association with the deep crustal extension response to the lithospheric thinning of the North China block. By superimposing the deep crustal extension, we propose that the present-day landform of the Luoyang basin was also shaped by fluvial erosion at the surface, which was accompanied by the expansion of Yihe and Luohe riverbeds during the Quaternary.

A Blueprint for an AI Bill of Rights for Education

Abstract In the wake of the introduction of ChatGPT, educators have been faced with pressure to adapt to the disruptive technology of AI chatbots. But these tools were not developed with educational applications in mind, and they come with many potential risks and harms to students. As educators decide how to address generative systems in their classrooms in the context of an ever-changing technological landscape, this essay offers a starting point for conversations about policy and protections. It begins with the rights articulated by the US Office of Science and Technology Policy and goes on to elaborate rights for educators and students, including institutional support for critical AI literacy professional development; educator collaboration on AI policy and purchase and implementation of generative systems; protection of student privacy and creative control; and consultation, notice, guidance, and appeal structures for students.

High‐Resolution Imaging of the Alaska‐Aleutian Megathrust Using P‐to‐S Mode Conversions From Local In‐Slab Earthquakes

AbstractThe top of the subducting plate is a thick, complex zone where the heterogeneous structure likely controls earthquake rupture processes. Imaging this heterogeneous channel typically involves active‐source methods with limited depth penetration, or low‐resolution teleseismic methods. To access short wavelengths at greater depth, we use high‐frequency P‐to‐S (PS, 1–15 Hz) mode‐converted arrivals from nearby earthquakes >50 km deep to image the plate interface at vertical scales <1 km. We use 37 broadband stations in southcentral Alaska between 2007 and 2008 at 10–15 km spacing, spanning the great 1964 earthquake rupture zone and adjacent deeper slow slip and tremor regions. The central 21 stations record high‐amplitude PS arrivals converting from the megathrust region, at depths corresponding to the top of a prominent low‐velocity zone (LVZ) in receiver function images. The PS/P amplitude ratio (APS_P) varies along strike and with depth of the conversion point but is independent of earthquake location and varies slowly between adjacent stations. APS_P changes with slab depth, indicating changes in lithology or fluid content of the plate interface, consistent with transitions in slip behavior from locked to slow slip. High APS_P cannot be explained by a velocity step or a single low‐velocity, high Vp/Vs layer, but requires several alternating high and low‐velocity layers. These observations indicate that the LVZ is a highly heterogeneous channel at multiple scales, resembling a subduction channel or sheared zone of metasediment and altered crust as observed in many exhumed subduction zones.

Risk Factors for Lower Extremity Minor Amputation Conversion to Major Amputation

Minor lower extremity amputations (LEAs) have become an important part of the limb salvage approach but are not as benign as previously thought. This study investigates the difference in outcome between toe/ray versus midfoot amputations and the risk factors for major amputation conversion associated with each procedure. We performed retrospective chart review of foot amputation patients at a single tertiary care medical center with a primary end point of conversion to major amputation and secondary end points of 1-year wound healing and mortality rate. We collected data on relevant medical comorbidities, noninvasive vascular imaging, revascularization, repeat amputations, wound healing rate, and 1-year mortality. Patients were separated into toe/ray amputations versus midfoot amputation groups and compared using descriptive statistics, Chi-squared tests, Cox proportional hazards, and a multivariate logistic regression model. A total of 375 amputations were included in the analysis. 65.3% (245 patients) included toe/ray amputations and 34.7% (130 patients) included midfoot amputations. We compared these 2 cohorts with regard to their rate of conversion to repeat minor and/or major amputation in addition to overall mortality. The toe/ray group underwent more repeat minor amputations within 1year after index amputation (34.7% vs. 21.5%, P=0.008) and wound healing (epithelization) at 90days was also higher in this group. The midfoot group had a higher conversion to major LEA within 1year on univariate analysis (20.8 vs. 6.9%, P<0.001). Overall 1-year mortality was 6.17% and there was no significant difference between groups. While there is a consistency with previous studies that found no significant overall difference in mortality between types of minor LEA, we have extended this previous work by demonstrating the independent risk factors for conversion to major amputation between types of minor LEA. Comparing these 2 groups will assist surgeons in choosing the appropriate level of amputations and will enhance patient's understanding of their chance of wound healing and risk of repeat amputation.

Building an inclusive botany: The “radicle” dream

Societal Impact StatementIt is important to recognize how our current understanding of plants has been shaped by diverse cultural contexts, as this underscores the importance of valuing and incorporating contributions from all knowledge systems in scientific pursuits. This approach emphasizes the ongoing bias, including within scientific practices, and the necessity of discussing problematic histories within spaces of learning. It is crucial to acknowledge and address biases, even within scientific endeavors. Doing so fosters a more inclusive and equitable scientific community. This article, while not comprehensive, serves as a starting point for conversation and an introduction to current work on these topics.SummaryIn response to a global dialog about systemic racism, ongoing inequalities, appeals to decolonize science, and the many recent calls for diversity, equity, accessibility, and inclusion, we draw on the narratives of plants to revisit the history of botany. Our goal is to uncover how exclusionary practices have functioned in the past and persist today. We also explore the numerous opportunities and challenges that arise in the era of information as we strive to establish a more inclusive field of botany. This approach recognizes and honors the contributions of historically marginalized groups, such as Black and Indigenous communities. We hope that this article can serve as a catalyst for raising awareness, fostering contemplation, and driving action toward a more equitable and just scientific community.

“Is It All or Nothing?” Day School Parents Consider the Anti-racist Implications of Their School Choices Through a Book Club

ABSTRACT This study explores the perspective of day school parents as they engage with questions of race with their children and in the context of their day school choice. We convened a book group in summer 2020. Nine White mothers of school-aged children met over four ninety minute sessions to discuss Margaret Hagermans’ (2018) White Kids: Growing up with privilege in a racially divided America. The book served as a jumping off point for conversation about how participants experience race in their own lives, how they engage with race within the family, and how they understand their children’s school to be engaging with issues of race. Hagerman followed families who chose mainly between public schools and secular private schools; our participants developed comparisons between Hagerman’s schools and Jewish day schools, and between themselves and Hagerman’s parents. While maintaining the uniqueness of the Jewish day school context, they also discovered commonalities with Hagerman’s parents related to privilege and social class and the disconnect between good intentions and outcomes.

Industrial crude bioethanol dehydration to ethylene: Doping ZSM-5 to enhance selectivity and stability

Although the conversion of bioethanol into light olefins is one of the most studied processes in biorefinery schemes, there is a need to develop materials more capable of operating at industrial conditions (WHSV > 20 h−1 crude bioethanol feed). Hence, in this study, we dehydrated crude bioethanol samples derived from sugarcane fermentation to produce ethylene over a series of H-ZSM-5 zeolites. Among them, H-ZSM-5 with different Si/Al ratios (26, 280, and 371) and doped with Ce and Cu were tested on the catalytic activity and stability. Accordingly, a 26 Si/Al ratio showed full conversion and ethylene selectivity at 300 °C with a WHSV of 30.2 h−1. When doping the zeolites, a decrease in relative crystallinity and a higher amount of acid sites were observed, which affected the interaction with reactants. This interaction was deeply analyzed by the in-situ DRIFTS, which showed that ethanol adsorption is lower for doped zeolites, but the desorption rate is higher, showing higher stability over longer reaction times. Therefore, the H-ZSM-5 with a Si/Al ratio of 26 and doped with Ce maintained its activity and improved its selectivity over 140 h under more drastic conditions of WHSV (42.3 h−1). These results elucidate that Ce-doped H-ZSM-5 zeolites can improve stability and represent a starting point for large-scale crude bioethanol conversion.

Effects of system pointing error and turbulence media anisotropy on the propagation of a perfect Laguerre-Gaussian vortex beam

We investigate the influences of the system pointing errors, oceanic turbulence, and transceiver parameters on the perfect Laguerre-Gaussian(PLG) in an optical propagation system with M-order quadrature amplitude modulation(M-QAM). The model of the ABER for turbulent seawater propagation systems with pointing errors is created in Rytov approximation. The evolution of ABER under different modulation order M of QAM, signal-to-noise ratio (SNR) of the transceiver systems, and turbulent parameters of seawater shows with the increase of system pointing errors, there is a pointing error value corresponding to the conversion of modulation mode from 4-QAM to256-QAM of the system with the lowest ABER, and this conversion point is related to the aperture value of the transceiver of the system. The propagation systems with high-order modulation QAM and large-aperture optical transceivers have higher tolerance of system pointing error than those of low-order modulation QAM and small-aperture transceivers. The pointing error tolerance of the system with low PLG's radial order, low OAM topological charge, and high SNR of transceiver is larger than that of the system with high PLG's radial order, high OAM topological charge, low SNR of transceiver system. The PLG vortex has a better tolerance to pointing errors than the Bessel Gaussian beam.