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The location of Co and Ni promoter atoms in industrial-style hydrotreating catalysts is examined by combining aberration-corrected scanning transmission electron microscopy and electron energy loss spectrum imaging. The observations unambiguously demonstrate that both Co and Ni promoter atoms occupy sites at all low-indexed edge terminations of hexagonally shaped multi-layer MoS2 nanocrystals. In contrast, similar observations for single-layer MoS2 nanocrystals show that Co-promoter atoms preferentially attach at the (-1 0 0) S-edge termination and are absent at the (1 0 0) Mo-edge termination. The apparent discrepancy between single- and multi-layer MoS2 nanocrystals can be explained by the 2H-MoS2 crystal structure, for which successive MoS2 layers alternatingly expose Mo- and S-edge terminations in any of the low-indexed directions. Thus, the multi-layer Co-Mo-S and Ni-Mo-S nanocrystals, formed in the present type of industrial-style hydrotreating catalyst, are consistently described as a superposition of single-layer Co-Mo-S and Ni-Mo-S structures, and in turn, provide promoted edge sites with different steric accessibility for the organic compounds in mineral oil distillates.

In this essay, Russell G. Moses argues that Charles Sanders Peirce's article "Evolutionary Love" establishes a general normative framework for a logic of evolutionary, progressive imagination that can be used to elucidate an evolutionary continuity between the normative works of Jane Addams, John Dewey, and Alain Locke. This exercise contributes to an understanding of pragmatism as a philosophy that seizes insights from evolution in order to normatively reconstruct dynamic meanings of truth, reality, ethics, politics, and art. In a dynamic model of progressive evolution--one homologous to the Golden Rule of "love your neighbor"--we find a normative cosmology that animates the moral imagination of philosophy toward what Addams called "democracy and social ethics." Moses concludes that in the Peircean model, together with subsequent developments, we may ultimately apprehend that evolution suggests a general form of development that may be hypothesized as a worthy normative guide for universal progressive education.

In the present work, Banyan and Peepal fibre reinforced hybrid composites are prepared through hand Lay- up technique..The objective of the work is to investigate the hardness and flexural properties of eight varieties of banyan – peepal hybrid composites. The composites include banyan-peepal-banyan-peepal-banyan fibre composite, peepal-banyan-peepal-banyan-peepal fibre composite, banyan-copper-banyan-copper-banyan fibre composite (F1-Cu-F1-Cu-F1), peepal-copper-peepal-copper-peepal fibre composite, banyan-peepal-copper-peepal-banyan fibre composite, peepal-copper-banyan-copper-peepal fibre composite, peepal-banyan-copper-banyan-peepal fibre composite, and banyan-copper-peepal-copper-banyan fibre composite . Each of these composites is prepared in 00 orientations (i.e., fibres parallel each other), 450 (i.e., fibres at 450 to each other) and 900 orientations (i.e., fibres perpendicular to each other). It is observed from the results that, the hardness of F2-Cu-F1-Cu-F2 composite with 900 orientation is high and that of F1-F2-F1-F2-F1 composite with 450 orientation is low. It is also noticed that, the bending strength of F2-Cu-F1-Cu-F2 composite with 00 orientation is high and that of F2-F1-F2-F1-F2 composite with 450 orientation is low, and as far as the composites with 90⁰ orientations are considered, no results are obtained. Further it is noticed that, the hardness of all the eight composites with 90˚ orientation is found to be high compared to their remaining orientations and also the hardness of all the composites with 45˚ orientation is low compared to their 0˚ and 90˚ orientations

The role of defects in the chemical activity of the rutile TiO2(110) surface remains a rich topic of research, despite the rutile (110) being one of the most studied surfaces of transition-metal oxides. Here, we present results from hybrid functional calculations that reconcile apparently disparate views on the impact of donor defects, such as oxygen vacancies and hydrogen impurities, on the electronic structure of the (110) rutile surface. We find that the bridging oxygen vacancy and adsorbed or substitutional hydrogen are actually shallow donors, which do not induce gap states. The excess electrons from these donor centers tend to localize in the form of small polarons, which are the factual cause of the deep states ~1 eV below the conduction band, often observed in photoelectron spectroscopy measurements. Our results offer a new framework for understanding the surface electronic structure of TiO2 and related oxides. [ABSTRACT FROM AUTHOR]

Background: Diabetes is a controllable disease, yet many adults struggle with managing this disease and are living with uncontrolled diabetes. Often, this can be attributed to patients' inadequate health literacy affecting their diabetes management behaviors.Objective: The objective of this study was to explore perceived benefits, barriers, and self-efficacy of patients to learn about the influences on diabetes management behaviors among varying health literacy levels.Methods: This study included patients at a pharmacist-led diabetes center in Indiana. Patients were contacted via phone and asked if they would like to participate. Data were collected via a 30-minute interview. Interview questions based on the Health Belief Model were asked to assess patients' behaviors of diabetes management. For qualitative data analysis of interviews after transcription, codes were applied using the coding software NVivo (QSR International, Burlington, MA) with a combined deductive and inductive approach taken to code creation.Results: There were no thematic differences in narratives of those with adequate versus inadequate health literacy regarding self-efficacy. However, participants with inadequate health literacy were more likely to rely on others to maintain self-efficacy.Conclusions: Information gathered from this study will further the understanding of patients' self-efficacy to manage diabetes and its influence by health literacy and support from others. [ABSTRACT FROM AUTHOR]

Objective: To determine whether routine blood glucose assessment of patients admitted to hospital from emergency departments (EDs) results in higher rates of new diagnoses of diabetes and documentation of follow-up plans.Design, Setting: Cluster randomised trial in 18 New South Wales public district and tertiary hospitals, 31 May 2011 - 31 December 2012; outcomes follow-up to 31 March 2016.Participants: Patients aged 18 years or more admitted to hospital from EDs.Intervention: Routine blood glucose assessment at control and intervention hospitals; automatic requests for glycated haemoglobin (HbA1c ) assessment and notification of diabetes services about patients at intervention hospitals with blood glucose levels of 14 mmol/L or more.Main Outcome Measure: New diagnoses of diabetes and documented follow-up plans for patients with admission blood glucose levels of 14 mmol/L or more.Results: Blood glucose was measured in 133 837 patients admitted to hospital from an ED. The numbers of new diabetes diagnoses with documented follow-up plans for patients with blood glucose levels of 14 mmol/L or more were similar in intervention (83/506 patients, 16%) and control hospitals (73/278, 26%; adjusted odds ratio [aOR], 0.83; 95% CI 0.42-1.7; P = 0.61), as were new diabetes diagnoses with or without plans (intervention, 157/506, 31%; control, 86/278, 31%; aOR, 1.51; 95% CI, 0.83-2.80; P = 0.18). 30-day re-admission (31% v 22%; aOR, 1.34; 95% CI, 0.86-2.09; P = 0.21) and post-hospital mortality rates (24% v 22%; aOR, 1.07; 95% CI, 0.74-1.55; P = 0.72) were also similar for patients in intervention and control hospitals.Conclusion: Glucose and HbA1c screening of patients admitted to hospital from EDs does not alone increase detection of previously unidentified diabetes. Adequate resourcing and effective management pathways for patients with newly detected hyperglycaemia and diabetes are needed.Trial Registration: Australian New Zealand Clinical Trials Registry, ACTRN12611001007921. [ABSTRACT FROM AUTHOR]

J. Leonard Farmer, father of American Civil Rights activist James Farmer, Jr., was an important philosopher in his own right. The elder Farmer argued that spiritual insight is measured by its power to bring hope to hopelessness. When the practical problem presents itself as national destruction, exemplary spiritual insight transforms that sacrifice into a warrant that the values cut down shall become the end values of history. This insight finds its paradigm in the teachings of the Second Isaiah. [ABSTRACT FROM AUTHOR]

Depletion of oil and gas resources is a major concern for researchers and the global community. Researchers are trying to develop a way to overcome these issues using the Fischer-Tropsch synthesis (FTS) process. The FTS reaction converts a mixture of hydrogen and carbon monoxide gases into a liquid fuel. The reactions are performed in the reactor and in the presence of a catalyst. A series of catalysts, such as iron, cobalt, nickel, and ruthenium, have been used for the FTS process. In iron-based catalysts, the Fe5C phase is the active phase that produces C5+ hydrocarbons. At higher conversion rates, the presence of water in the products is a problem for cobalt catalysts because it can trigger catalyst deactivation mechanisms. Ni-based catalysts play key roles as base catalysts, promoters, and photothermal catalysts in FTS reactions to produce different useful hydrocarbons. Ruthenium catalysts offer not only high activity but also selectivity toward long-chain hydrocarbons. Moreover, depending on the Ru particle size and interaction with the oxide support, the catalyst properties can be tuned to enhance the catalytic activity during FTS. The detailed reaction pathways based on catalyst properties are explained in this article. This review article describes the issues and challenges associated with catalysts used for the FTS process. [ABSTRACT FROM AUTHOR]

This paper presents a reading of the Moses narratives in the Pentateuch in dialog with Emmanuel Levinas. It examines the encounter with the Other on the part of the two major characters, namely, Moses and G-d, insofar as each is revealed to the Other during the course of the narrative and each is transformed as a result of their interaction. It both affirms and tests Levinas's understanding of love or beneficence on the part of the Other by pointing to both the constructive aspects of Moses's and Gd's interrelationship as well as the tensions that emerge between them and the consequences that result. The paper argues that Levinas's understanding of encounter with the Other provides an appropriate hermeneutical standpoint from which to read biblical literature, but that his understanding of the beneficence of such encounter must be modified to account for the tensions and conflicts that emerge. The paper begins with a discussion of Levinas's hermeneutical perspectives, including his rejection of the concept of totality in favor of infinity, his concept of the Self formed in relation to the Other, his understanding of Face in relation to moral summons, and his understanding of ethics applied to both Moses/ Israel and to G-d. Issues treated include Moses's encounter with G-d in the burning bush and plague narratives (Exodus 3-15); conflict between Moses and G-d in the golden calf episode (Exodus 32-34); the spy narratives (Numbers 13-14); and the call for water from the rock at Meribah (Numbers 20; Deuteronomy 34). [ABSTRACT FROM AUTHOR]

Industrially, petroleum naphtha reforming and steam cracking are two major multistep and energy-intensive sources for p-xylene production. Additionally, p-xylene is also produced by selective toluene disproportionation, heavy (C9) aromatics trans-alkylation and isomerization of xylenes. Rapidly changing market dynamics from fuels to petrochemicals coupled with growing petrochemicals demand has led to the further exploration of economical and highly p-xylene selective processes by using surplus low-value aromatics. Methylation of toluene with methanol has been envisaged as one such potential opportunity to produce p-xylene. For the purpose, significant efforts have been made in the past forty years to develop suitable shape selective zeolite catalysts and technologies to make toluene methylation a highly p-xylene selective process. Current paper briefly highlights various advancements in the toluene methylation process development and aims to provide an extensive review of several works put up in the past to design suitable catalysts, catalyst's limitations and developmental challenges for toluene methylation. Further, this paper provides an useful insight for two competing chemistries of toluene alkylation and side-by-side methanol reactions. Finally, motivated by competitive chemistry of methanol conversion reactions, existing catalytic limitations and novel synthesis opportunities in engineering shape selective zeolite catalysis, a way forward is proposed to arrive at a logical and futuristic catalyst design strategy for p-xylene production via toluene methylation. The proposed strategy is envisaged to offer low-to-moderate catalyst acidity, improved toluene methylation activity, high p-xylene selectivity and improved catalyst life which, otherwise, up till now have been the bottlenecks to develop distinctly economical toluene alkylation to p-xylene process. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The development of renewable and affordable energy is crucial for building a sustainable society. In this context, establishing a sustainable infrastructure for renewable energy requires the integration of energy storage, specifically use of renewable hydrogen. The hydrogen evolution reaction (HER) of electrochemical water splitting is a promising method for producing green hydrogen. Recently, two-dimensional nanomaterials have shown great promise in promoting the HER in terms of both fundamental research and practical applications due to their high specific surface areas and tunable electronic properties. Among them, molybdenum disulfide (MoS2), a non-noble metal catalyst, has emerged as a promising alternative to replace expensive platinum-based catalysts for the HER because MoS2 has a high inherent activity, low cost, and abundant reserves. At present, greatly improved activity and stability are urgently needed for MoS2 to enable wide deployment of water electrolysis devices. In this regard, efficient strategies for precisely modifying MoS2 are of interest. Herein, the progress made with MoS2 as an HER catalyst is reviewed, with a focus on modification strategies, including phase engineering, morphology design, defect engineering, heteroatom doping, and heterostructure construction. It is believed that these strategies will be helpful in designing and developing high-performance and low-cost MoS2-based catalysts by lowering the charge transfer barrier, increasing the active site density, and optimizing the surface hydrophilicity. In addition, the challenges of MoS2 electrocatalysts and perspectives for future research and development of these catalysts are discussed. [ABSTRACT FROM AUTHOR]

Use of oral agents to treat gestational diabetes mellitus remains controversial. Recent recommendations from the Society for Maternal-Fetal Medicine assert that metformin may be a safe first-line alternative to insulin for gestational diabetes mellitus treatment and preferable to glyburide. However, several issues should give pause to the widespread adoption of metformin use during pregnancy. Fetal concentrations of metformin are equal to maternal, and metformin can inhibit growth, suppress mitochondrial respiration, have epigenetic modifications on gene expression, mimic fetal nutrient restriction, and alter postnatal gluconeogenic responses. Because both the placenta and fetus express metformin transporters and exhibit high mitochondrial activity, these properties raise important questions about developmental programming of metabolic disease in offspring. Animal studies have demonstrated that prenatal metformin exposure results in adverse long-term outcomes on body weight and metabolism. Two recent clinical randomized controlled trials in women with gestational diabetes mellitus or polycystic ovary syndrome provide evidence that metformin exposure in utero may produce a metabolic phenotype that increases childhood weight or obesity. These developmental programming effects challenge the conclusion that metformin is equivalent to insulin. Although the Society for Maternal-Fetal Medicine statement endorsed metformin over glyburide if oral agents are used, there are few studies directly comparing the 2 agents and it is not clear that metformin alone is superior to glyburide. Moreover, it should be noted that prior clinical studies have dosed glyburide in a manner inconsistent with its pharmacokinetic properties, resulting in poor glycemic control and high rates of maternal hypoglycemia. We concur with the American Diabetes Association and American Congress of Obstetricians and Gynecologists, which recommend insulin as the preferred agent, but we believe that it is premature to embrace metformin as equivalent to insulin or superior to glyburide. Due to the uncertainty of the long-term metabolic risks of either metformin or glyburide, we call for carefully controlled studies that optimize oral medication dosing according to their pharmacodynamic and pharmacokinetic properties in pregnancy, appropriately target medications based on individual patterns of hyperglycemia, and follow the offspring long-term for metabolic risk. [ABSTRACT FROM AUTHOR]

This paper discusses the effect of a ZnGeN2 layer inserted into the wells of Type-I InGaN/GaN QWs LEDs on the electrical and optical properties by using the Silvaco TCAD Simulator. First, the new structure is compared to the standard type-I LED based on InGaN. We found that using ZnGeN2 layer in the In0.2Ga0.8N-QWs LED leads to wavelength extending from the blue to the red region. Next, we highlighted the effect of quantum well number and In-molar fraction in the wells of InxGa1-xN/ZnGeN2 type-II LEDs. As a result, increasing the number of wells from two to six QWs creates an extension of spontaneous emissions while keeping a low concentration of indium in the wells (x = 0.16) and improving the electrical and optical properties, as we found an improvement in light output power of 10.7% at 40Acm-2. [ABSTRACT FROM AUTHOR]

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The catalytic volcano activity models are the quantified and visualized tools of the Sabatier principle for heterogeneous catalysis, which can depict the intrinsic activity optima and trends of a catalytic reaction as a function of the reaction descriptors, i.e., the bonding strengths of key reaction species. These models can be derived by microkinetic modeling and/or free energy changes in combination with the scaling relations among the reaction intermediates. Herein, we introduce the CatMath—an online platform for generating a variety of common and industrially important thermal + electrocatalysis. With the CatMath, users can request the volcano models for available reactions and analyze their materials of interests as potential catalysts. Besides, the CatMath provides the function of the online generation of Surface Pourbaix Diagram for surface state analysis under electrocatalytic conditions, which is an essential step before analyzing the activity of an electrocatalytic surface. All the model generation and analysis processes are realized by cloud computing via a user-friendly interface. [ABSTRACT FROM AUTHOR]

Due to unique and excellent properties, carbon nanotubes (CNTs) are expected to become the next-generation critical engineering mechanical and energy storage materials, which will play a key role as building blocks in aerospace, military equipment, communication sensing, and other cutting-edge fields. For practical application, the assembled macrostructures from individual CNTs are the common paradigms such as fibers or films. As the main representative, CNT films can not only retain the unique properties of their CNTs components, but also are more likely for mass-production than other macrostructures. Therefore, in this review, we focus on preparation of CNT films and discuss their emerging applications in the field of mechanical and electrochemical energy storage/conversion. Firstly, different preparation processes are systematically summarized. Then we introduce some typical strategies to improve their mechanical performances besides strengthening mechanism. Based on the progress of mass-production and performance optimization, we further discuss their potential utilization in mechanical and electrochemical energy storage/conversion devices. Finally, future perspectives for the development of CNT films in both production and application are proposed. We hope that this review will shed light on the preparation/assembly of CNT films and integrated application of excellent properties from individual to macroscopic dimensions. Moreover, the preparation and crossscale application paradigms of CNT films also offer a good model for other macroscopic ordered assemblies of one-dimensional nanomaterials. [ABSTRACT FROM AUTHOR]

Two-dimensional transition metal dichalcogenides (TMDs) have gained attention as potent catalysts for the hydrogen evolution reaction (HER). The traditional trial-and-error methodology for catalyst development has proven inefficient due to its costly and time-intensive nature. To accelerate the catalyst development process, the Gibbs free energy of hydrogen adsorption (Δ G H ∗ ), computed using the density functional theory (DFT), is widely used as the paramount descriptor for evaluating and predicting HER catalyst performance. However, DFT calculations for Δ G H ∗ are time-consuming and thus pose a challenge for high-throughput screening. Herein, we devise a predictive model for Δ G H ∗ within transition metal-doped TMD systems using a machine learning (ML) framework. We calculate DFT Δ G H ∗ values for 150 TM-doped MX2 (CrS2, MoS2, WS2, MoSe2, and MoTe2) and apply various ML algorithms. We validate the universality of our model by constructing 15 new external test sets. The prediction results show a high correlation coefficient of R 2 = 0.92. Based on feature analysis, the three most important parameters are the number of valence electrons of the doped transition metal, the distance of the valence electrons of the doped transition metal, and the electronegativity of the doped transition metal. Our DFT-based ML model provides a useful guideline for the material development process through Δ G H ∗ prediction and facilitates the efficient design of transition metal dichalcogenide catalysts that exhibit superior HER activity. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to an article about the new diagnostic criteria for the diagnosis of gestational diabetes mellitus.

Copyright of University Chemistry is the property of Peking University, College of Chemistry & Molecular Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hybrid density functional theory calculations are used to investigate different mechanisms of the isomerization of n-butane to isobutane via intermediate formation of olefins. The monomolecular mechanism for isomerization of butene and isobutene is found to be prevalent, with a Gibbs free energy barrier of 155 kJ/mol at 400°C, compared to the bimolecular mechanism (190 kJ/mol) due to less favorable entropy for the latter. Hydrogen transfer reactions that convert olefins into alkanes (and vice versa) are also included in the investigations, and show a free energy barrier of 203 kJ/mol for conversion of isobutene to isobutane. Additionally, a methyl transfer mechanism is discussed as a possible pathway for formation of C3 and C5 side products, in comparison to the bimolecular mechanism; the highest barrier of the initial methyl transfer is calculated to be 227 kJ/mol. We discuss the influence of entropy and anharmonicity on all mechanisms, stating that through the uncertainties in computational methods when calculating these systems, the calculated reaction barriers are likely to be overestimated here. [ABSTRACT FROM AUTHOR]

It is significant to optimize geometric configuration of metal catalytic sites and boost their catalytic activity. Herein, we synthesized isolated single Zn-N4 sites on N-doped carbon (Zn-CN) by pyrolyzing zeolite imidazole framework-8 (ZIF-8) at different temperatures. For the reciprocal transformation between benzyl alcohol and benzaldehyde, the catalytic activities of Zn-CN catalysts exhibited a volcano-like trend as the pyrolysis temperatures increased. The optimal catalyst was Zn-CN-900, with outstanding catalytic activity exceeding commercial 20 wt.% Pd/C and 20 wt.% Pt/C, promising to substitute the noble metal-based catalysts. X-ray absorption near-edge structure (XANES) measurements and density functional theory (DFT) calculation revealed the gradual transformation from tetrahedral ZnN4 sites of ZIF-8 into planar ZnN4 sites above 700 °C, with the maximum planar ZnN4 sites in Zn-CN-900. The stronger adsorption between reactants and planar ZnN4 sites facilitated the activation of reactants compared with tetrahedral ZnN4 sites. This work will provide valuable insight into rational design of efficient catalysts by optimizing geometric configuration of catalytic sites. [ABSTRACT FROM AUTHOR]

Oxygen reduction reactions (ORRs) are unanimously a key factor of system performances in bioelectrochemical systems (BESs), low-temperature fuel cells, and generally in several electrochemical platforms. Platinum (Pt)-based catalyst is the finest electrocatalyst for ORR in BESs; however, it is constrained by its low abundance, high price, and poor catalytic durability in an electrochemical setup for cathodic reaction kinetics. In recent years, significant efforts in trimming the metal-based catalyst up to nanoscale to cater high performance of ORR have been explored. Still, there are many opportunities to improve catalyst performance at cathode through proper selection of an efficient low-cost metal-based ORR catalyst. Molybdenum (Mo) with its multi-dimensional form as 2D and 3D layers and synergistic combination with other non-metals offers prospects of extraordinary performance as low-cost metal-based ORR catalyst over the Pt in delivering enhanced ORR potential. The present review throws light on current requirements of a sturdier catalyst material and thus provides a comprehensive review on the continuing efforts in exploring the possibility of Mo as a low-cost metal-based ORR catalyst. This literature analysis would enlighten the significance of ORR in BESs, followed by the electrochemistry of Mo-based cathodic catalyst, its underlying mechanism and performance limiting factors in the operation of ORR. Moreover, the extensive and systematic acumen in the context of Mo-based catalytic formulations for increased ORR potentials including nano-composite Mo-cathode catalyst; development of Mo-catalyst with varied configurations; carbon-supported Mo-catalyst; morphological changes; surface area modifications; and Mo-coupling with other transition metal and its derivatives were discussed in great detail to provide prospective application of Mo-based catalyst. Lastly, numerous opportunities and projections for future research in fabrication, juxtaposition, and implementation of Mo-based cathodic catalysts and consequent recommendations were discussed as conclusive remarks for bringing out the state-of-the-art review on this subject. [ABSTRACT FROM AUTHOR]

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Strain engineering is a useful strategy for modifying the catalytic activity of electrocatalysts. However, in-situ visual characterization of the strain effect on the catalytic activity at nanoscale remains a huge challenge. Herein, we performed in-situ electrochemical scanning tunneling microscopy (EC-STM) imaging measurements at the local strained regions of extruded single-crystal molybdenum dioxide (MoO2) sheets with combination of current noise analysis (n-EC-STM). The intensity-enhanced noise was observed at the local strained region compared to the unstrained regions in the same frame, which reveals the positive effect of compressive strain on the hydrogen evolution reaction (HER) activity of MoO2 provided that the intensity of noise is positively correlated with catalytic HER Faradic current. Therefore, we clearly "see" the strain-induced enhancement of HER activity of MoO2 at nanoscale by means of noise visualization. This work extends the visual characterization of strain engineering in electrocatalysis and related fields. [ABSTRACT FROM AUTHOR]

Herein, we designed and constructed a mesoporous LaAlOx via a solvent evaporation induced selfassembly protocol. The structure and physicochemical property of the corresponding NiMo supported catalyst was analyzed by a set of characterizations, and its catalytic activity was investigated for hydrodesulfurization (HDS) of 4,6-dimethyldibenzothiophene. It has confirmed that the incorporation of La profoundly facilitate the generation of "Type II" NiMoS phase by weakening the interaction of MoeO eAl leakage and promoting the sulfidation of both Ni and Mo oxides as well as changing the morphology of Ni promoted MoS2 slabs, thereafter boosting the HDS performance substantially. The finding here may contribute to the fundamental understanding of structure-activity in ultra-deep desulfurization and inspire the advancement of highly-efficient HDS catalyst in future. [ABSTRACT FROM AUTHOR]

The presence of waste tires on open fields or households creates an ideal breeding ground for disease-carrying vermin, threatening human well-being. There are various technologies studied for efficient use of waste tires, such as pyrolysis, which results in char, oil, and non-condensable gases. Tire pyrolytic oil (TPO) has been reported to be similar to commercial diesel fuel. The current hurdle for using TPO in commercial diesel engines is the available sulfur content (>1.0 wt%). The disadvantages of sulfur in liquid fuels are its ability to reduce the engine's life due to corrosion and the undesirable emission of SOx that subsequently damages public health and property. There is a rising need to develop efficient technologies for the desulfurization of such liquid fuels. Besides conventional hydrodesulfurization, other emerging technologies include adsorption, oxidation, photocatalytic degradation, and biological desulfurization. This paper reviews the status of pyrolysis of waste tires and desulfurization technologies for TPO. Implications: The nature of tires makes them extremely challenging to recycle due to the available chemically cross-linked polymer and, therefore, they are neither fusible nor soluble and, consequently, cannot be remolded into other shapes without serious degradation. The presence of tire waste on open fields or households creates an ideal breeding ground for disease-carrying vermin which pose a threat to humans. Also, disposal in landfills can lead to groundwater pollution by heavy metals and cause hazardous and uncontrolled fires. Owing to the growing environmental concerns, the exploration of economically viable and environmentally friendly techniques for the management of waste tires has been intensified in the recent past. Thermochemical routes such as combustion, gasification, and pyrolysis are important in the management of waste tires, reducing the environmental impacts of tire volarization, and allowing for the recovery of products. Given the depletion of fossil fuels and to meet the ever-growing demand for fuel energy, several initiatives to find alternative fuel sources are currently being taken. Fuel oil obtained from the pyrolysis of waste tires is becoming a promising alternative source of energy given its availability and higher heating value. Pyrolysis, an eco-friendly process, is the heating of matter in the absence of oxygen and is normally practiced for the thermochemical decomposition of different types of feedstock including biomass, coal, tires, and municipal solid waste. This paper reviews the current studies for pyrolysis of waste tires and multiple desulfurization technologies used for treating TPO globally. The detailed specification on operating conditions for the pyrolysis reactor in achieving desirable products in terms of composition and ratios are discussed. [ABSTRACT FROM AUTHOR]

Nitrides are of particular interest in energy applications given their suitability to photocatalytically generate H 2 from aqueous solutions. However, one of the drawbacks of nitrides is the decomposition they suffer when used in photoelectrochemical cells. Here, we report the improvement of the catalytic performance and chemical stability of a GaN electrode when it is decorated with Fe 2 O 3 particles compared with an undecorated electrode. Our results show a higher reaction rate in the Fe 2 O 3 /GaN electrode, and that photocorrosion marks take more than 20 times longer to appear on it. We also characterized the crystalline properties of the Fe 2 O 3 particles with transmission electron microscopy. The results show that the Fe 2 O 3 particles keep an epitaxial relationship with GaN that follows the Fe 2 O 3 [Formula: see text]GaN[Formula: see text] and Fe 2 O 3 [Formula: see text]GaN[Formula: see text] symmetry constraints. We also characterized an Fe 2 O 3 (thin film)/GaN electrode, however it did not present any catalytic improvement compared with a bare GaN electrode. The epitaxial relationship found between the Fe 2 O 3 thin film and GaN exhibited the Fe 2 O 3 [Formula: see text]GaN[Formula: see text] and Fe 2 O 3 [Formula: see text]GaN[Formula: see text] symmetry constraints.

The change in the coordination environment of the active sites of a fuel cell cathode catalyst provides a new modulation strategy for stimulating the catalyst's oxygen reduction reaction activity. The thermodynamic and electronic properties of the FeCoN5A and FeCoN6A catalyst structures with nonmetallic A-doped (A = B, N, O, P, and S) coordination were calculated and analyzed based on density functional theory. The modulation order of G⋆OH by different A-doped FeCo bimetal pairs (BMPs) was as follows: S > P > O > N/C > B. There was a dynamic distribution of charges in the coordination environment during the adsorption of OH, which resulted in inversely proportional relationship with the charge transfer between the adsorbate OH, active site, first coordination layer, and second coordination layer in turn. Descriptors of the orbital energy levels of neighboring nonmetal atoms were constructed based on the p-electron number and electronegativity of the doped nonmetal A. The change of the orbital energy levels of the first coordination atom during the adsorption process caused the structure to exhibit different adsorption energies. This study provides new insights on the non-metallic modulation of the M-N-C coordination environment to improve the oxygen reduction reaction activity. [ABSTRACT FROM AUTHOR]

Designing catalyst to achieve ammonia synthesis at mild conditions is a meaningful challenge in catalysis community. Defective g-C3N4 nanosheet supported single-cluster ruthenium and iron catalysts were investigated for their ammonia synthesis performance. Based on density functional theory (DFT) calculations and microkinetic simulations, Ru3 single-cluster anchored on defective g-C3N4 nanosheet (Ru3/Nv-g-C3N4) has a turnover frequency (TOF) 5.8 times higher than the Ru(0001) step surface at industrial reaction conditions of 673 K and 100 bar for ammonia synthesis. In other words, similar TOFs could be achieved on Ru3/Nv-g-C3N4 at much milder conditions (623 K, 30 bar) than on Ru(0001) (673 K, 100 bar). Our computations reveal the reaction proceeds parallelly on Ru3/Nv-g-C3N4 through both dissociative and alternative associative mechanisms at typical reaction conditions (600–700 K, 10–100 bar); N-N bond cleavage of *N2 and *NNH from the two respective pathways controls the reaction collectively. With increasing temperatures or decreasing pressures, the dissociative mechanism gradually prevails and associative mechanism recedes. In comparison, Fe3/Nv-g-C3N4 catalyst shows a much lower catalytic activity than Ru3/Nv-g-C3N4 by two orders of magnitude and the reaction occurs solely through the dissociative pathway. The finding provides a prospective candidate and deepens the mechanistic understanding for ammonia synthesis catalyzed by single-cluster catalysts (SCCs). [ABSTRACT FROM AUTHOR]

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Sodalites of the general type |Na8X2|[T1T2O4]6 with X = Cl−, Br−, I− have been synthesized for Al–Si, Ga–Si, Al–Ge and Ga–Ge as T1–T2 frameworks. The structures were examined using in-house and synchrotron X-ray diffraction, Raman spectroscopy, force-field structure optimizations and DFT based ab-initio molecular dynamics (MD) computations. Calculated phonon density of states (PDOS) of the 12 compounds show only minor differences within a framework composition with a lowering of certain phonon energies with increasing anion size. Earlier published Debye and Einstein temperatures obtained with a Debye-Einstein-anharmonicity (DEA) model approach are confirmed using the determined low-temperature lattice parameters (18 K–293 K) and show no correlation with the respective PDOS. Small-box refinements against radial pair distribution functions (PDF) allowed the determination of anisotropic displacement ellipsoids (ADP) for Na+ and O2−, indicating a strong dependency of the ADP of Na+ on the chemical composition. Significantly lower thermal displacements from MD calculations suggested an influence of structural displacements. For compounds with an aspherical ADP for sodium, structural models could be refined in which the sodium is located on two 8e or one 24i site (both partially occupied), and also temperature-dependent (100 K–300 K) for the compounds with Ga–Ge framework. 3D-plots of the bond-valence sums of Na+ further validate the structural differences. These results imply that the local structure of halide-sodalites in many cases is not best described by the known average structure and may even not be cubic. [ABSTRACT FROM AUTHOR]