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We consider the problem of controlling cascade systems consisting of two linear dynamic blocks and two saturation elements arranged according to the N-L-N-L series configuration. A cascade controller is considered and its performances are formally analyzed using input-output stability tools. In addition to global boundedness of all signals of the closed-loop system, the controller is formally shown to enjoy a l2 -tracking performance in presence of arbitrary-shape inputs ( i.e. reference signal, disturbance). [ABSTRACT FROM AUTHOR]

Cationic lipids are crucial in medical and biotechnological applications including cellular transfection and gene delivery. Ionizable cationic lipids are critical components of the mRNA‐based COVID vaccines while permanently charged cationic lipids have shown promise in cancer treatment. Despite significant research progress over the past few decades in designing improved, biocompatible cationic lipids, their transfection efficiency remains lower than that of viral vectors. Cationic lipids with additional functionalities like fusogenicity, stimuli‐responsiveness, targeting capabilities, and therapeutic activity have been engineered to improve their performance. This review highlights the importance of molecular hybridization toward the design of biocompatible cationic lipids having fusogenic, stimuli‐responsive, targeting, or therapeutic properties. This review mainly focuses on cationic lipids, having a permanent positive charge in the headgroup region, as these are typically employed to both increase cellular interactions and for improved loading, particularly for anionic nucleic acid‐based therapeutics and vaccines. Structure–activity relationships between the lipid chemical structure (headgroup, spacer, hydrocarbon chain) and, to a lesser extent, the self‐assembled nanostructure and the intrinsic biological activity of the multi‐functional cationic lipids are described. Finally, the challenges involved in developing smart lipids without affecting their inherent capacity to self‐assemble into structured nano‐carriers are discussed. [ABSTRACT FROM AUTHOR]

Dendritic mesoporous silica nanoparticles own three‐dimensional center‐radial channels and hierarchical pores, which endows themselves with super‐high specific surface area, extremely large pore volumes, especially accessible internal spaces, and so forth. Dissimilar guest species (such as organic groups or metal nanoparticles) could be readily decorated onto the interfaces of the channels and pores, realizing the functionalization of dendritic mesoporous silica nanoparticles for targeted applications. As adsorbents and catalysts, dendritic mesoporous silica nanoparticles‐based materials have experienced nonignorable development in CO2 capture and catalytic conversion. This comprehensive review provides a critical survey on this pregnant subject, summarizing the designed construction of novel dendritic mesoporous silica nanoparticles‐based materials, the involved chemical reactions (such as CO2 methanation, dry reforming of CH4), the value‐added chemicals from CO2 (such as cyclic carbonates, 2‐oxazolidinones, quinazoline‐2,4(1H,3H)‐diones), and so on. The adsorptive and catalytic performances have been compared with traditional silica mesoporous materials (such as SBA‐15 or MCM‐41), and the corresponding reaction mechanisms have been thoroughly revealed. It is sincerely expected that the in‐depth discussion could give materials scientists certain inspiration to design brand‐new dendritic mesoporous silica nanoparticles‐based materials with superior capabilities towards CO2 capture, utilization, and storage. [ABSTRACT FROM AUTHOR]

Detergents are amphiphilic molecules that serve as enabling steps for today's world applications. The increasing diversity of the detergentome is key to applications enabled by detergent science. Regardless of the application, the optimal design of detergents is determined empirically, which leads to failed preparations, and raising costs. To facilitate project planning, here we review synthesis strategies that drive the diversification of the detergentome. Synthesis strategies relevant for industrial and academic applications include linear, modular, combinatorial, bio‐based, and metric‐assisted detergent synthesis. Scopes and limitations of individual synthesis strategies in context with industrial product development and academic research are discussed. Furthermore, when designing detergents, the selection of molecular building blocks, i. e. head, linker, tail, is as important as the employed synthesis strategy. To facilitate the design of safe‐to‐use and tailor‐made detergents, we provide an overview of established head, linker, and tail groups and highlight selected scopes and limitations for applications. It becomes apparent that most recent contributions to the increasing chemical diversity of detergent building blocks originate from the development of detergents for membrane protein studies. The overview of synthesis strategies and molecular blocks will bring us closer to the ability to predictably design and synthesize optimal detergents for challenging future applications. [ABSTRACT FROM AUTHOR]

Background: Gestational diabetes mellitus (GDM) has a strong genetic predisposition. Integrating metabolomics with Mendelian randomisation (MR) analysis offers a potent method to uncover the metabolic factors causally linked to GDM pathogenesis., Objectives: This study aims to identify specific metabolites and metabolic pathways causally associated with GDM susceptibility through a comprehensive MR analysis. Additionally, it seeks to explore the potential of these identified metabolites as circulating biomarkers for early GDM detection and risk assessment. Furthermore, it aims to evaluate the implicated metabolic pathways as potential therapeutic targets for preventive or interventional strategies against GDM., Methods: A two-sample MR study was conducted using summary statistics from a metabolite genome-wide association study (GWAS) of 8299 individuals and a GDM GWAS comprising 13,039 cases and 197,831 controls. Rigorous criteria were applied to select robust genetic instruments for 850 metabolites., Results: MR analysis revealed 47 metabolites exhibiting putative causal associations with GDM risk. Among these, five metabolites demonstrated statistically significant associations after multiple-testing correction: Beta-citrylglutamate, Isobutyrylcarnitine (c4), 1,2-dilinoleoyl-GPC (18:2/18:2), Alliin and Cis-3,4-methyleneheptanoylcarnitine. Importantly, all these metabolites exhibited protective effects against GDM development. Additionally, metabolic pathway enrichment analysis implicated the methionine metabolism and spermidine and spermine biosynthesis pathways in the pathogenesis of GDM., Conclusion: This comprehensive MR study has robustly identified specific metabolites and metabolic pathways with causal links to GDM susceptibility. These findings provide novel insights into the metabolic underpinnings of GDM aetiology and offer promising translational implications. The identified metabolites could serve as potential circulating biomarkers for early detection and risk stratification, while the implicated metabolic pathways may represent therapeutic targets for preventive or interventional strategies against GDM., (© 2024 John Wiley & Sons Ltd.)

The catalytic performance of supported metals is greatly influenced by the interaction with the support material. The role of the support becomes even more important when dealing with metal nanoparticles and high reaction temperatures. Herein, we show that interfacial sites between two metal oxides, MgAlOx and ZrO2 can bestow high stability as well as enhanced reactivity to nickel (Ni) nanoparticles. We use the MgAlOx as thin oxides on an underlying bulk ZrO2. We demonstrate the effect of the metal‐support interactions (MSI) in different support locations on the performance in dry reforming of methane (DRM). We find that the rate of DRM catalysis produces a concave‐down trend with respect to Ni loading with a maximum at ~0.8–1.1 % wt Ni. Measuring the Ni2p3/2 binding energy (BE), we find a similar concave‐down trend whereas for the Mg2p BE we find a concave‐up trend with respect to the Ni loading both with the maximum and minimum centered at 0.8–1.1 % wt Ni, respectively. These trends were correlated with the stability of Ni calculated by DFT. Overall, our results suggest that heterointerfacial sites can be used to tailor moderate MSI, which can be used in the design of DRM catalyst with significantly increased activity and high stability. [ABSTRACT FROM AUTHOR]

The gasification of biomass with supercritical water, also known as SCWG, is a sustainable method of hydrogen production. The process produces a mixture of hydrogen, carbon oxides, and hydrocarbons. Upgrading this mixture through steam or dry reforming of hydrocarbons to create synthesis gas and then extra hydrogen is a viable way to increase hydrogen production from biomass. This literature review discusses combining these two processes and recent experimental work on catalytic SCWG of biomass and its model compounds and steam/dry reforming of produced hydrocarbons. It focuses on catalysts used in these processes and their key criteria, such as activity, selectivity towards hydrogen and methane, and ability to inhibit carbon formation and deposition. A new criterion is proposed to evaluate catalyst performance in biomass SCWG and the need for further upgrading via reforming, based on the ratio of hydrogen bound in hydrocarbons to total hydrogen produced during SCWG. The review concludes that most catalysts used in biomass SCWG trap a large proportion of hydrogen in hydrocarbons, necessitating further processing of the product stream. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) utilization and conversion, as one of the main parts of carbon capture, utilization, and storage (CCUS), is not only considered an important way to mitigate global warming but also an attractive industrial route to produce valuable fuels and chemical feedstocks. Catalytic dry reforming of methane (DRM) is a promising technology for carbon dioxide utilization and conversion as it can produce syngas, carbon monoxide (CO), and hydrogen (H2) for widespread industrial production processes. In most studies of the DRM reaction, a relatively high operational temperature (i.e., >700°C) has been applied since the reactivity limitation of widely used Ni‐based catalysts at low temperatures and the extremely endothermic property of the DRM reaction. However, high cost and high requirement of thermal stability for catalysts have become a severe problem impeding the further commercialization of DRM technology. Decreasing the operational temperature (i.e., <700°C) is considered a promising way for further application of the DRM route to convert CO2 and produce syngas. However, traditional Ni‐based catalysts suffered from unsatisfied reactivity and severe coke formation, leading to quick deactivation at low temperatures. Developing a catalyst with excellent catalytic activity, coke resistance, and improved thermal stability is necessary for low‐temperature DRM reactions. In recent years, with significant development in materials, catalyst design, and computational simulation, some synthesized catalysts have achieved considerable improvement in catalytic performance in low‐temperature DRM. Hence, a review of recent development on low‐temperature DRM catalysts is provided here to further guide and profoundly understand catalyst design for low‐temperature DRM. [ABSTRACT FROM AUTHOR]

Nanoporosity is clearly beneficial for the performance of heterogeneous catalysts. Although exsolution is a modern method to design innovative catalysts, thus far it is predominantly studied for sintered matrices. A quantitative description of the exsolution of Ni nanoparticles from nanoporous perovskite oxides and their effective application in the biogas dry reforming is here presented. The exsolution process is studied between 500 and 900 °C in nanoporous and sintered La0.52Sr0.28Ti0.94Ni0.06O3±δ. Using temperature‐programmed reduction (TPR) and X‐ray absorption spectroscopy (XAS), it is shown that the faster and larger oxygen release in the nanoporous material is responsible for twice as high Ni reduction than in the sintered system. For the nanoporous material, the nanoparticle formation mechanism, studied by in situ TEM and small‐angle X‐ray scattering (SAXS), follows the classical nucleation theory, while on sintered systems also small endogenous nanoparticles form despite the low Ni concentration. Biogas dry reforming tests demonstrate that nanoporous exsolved catalysts are up to 18 times more active than sintered ones with 90% of CO2 conversion at 800 °C. Time‐on‐stream tests exhibit superior long‐term stability (only 3% activity loss in 8 h) and full regenerability (over three cycles) of the nanoporous exsolved materials in comparison to a commercial Ni/Al2O3 catalyst. [ABSTRACT FROM AUTHOR]

The hybrid hydrothermal carbonization and ultrasound technology (HHTC‐Us) efficiently utilizes the function of both ultrasounds‐assisted and hydrothermal carbonization for hydrochar production. The HHTC‐Us of oil palm residues plays an essential role in hydrochar production. Hydrochar is a carbon‐rich material potentially produced from oil palm biomass, which has gained great interest due to its unique properties. Four main topics were highlighted: the production of crude palm oil and impacted biomass residue generation, properties and potential values of oil palm biomass conversion as hydrochar, hybrid hydrothermal carbonization reaction routes, and processing parameters that affect the HHTC‐Us technology. The review elucidates the promising production process or modification of hydrochar from oil palm biomass residues through hybrid technology. The technology potentially enhanced sustainability, creating challenges and new opportunities. [ABSTRACT FROM AUTHOR]

Polyol pathway enzymes, aldose reductase (EC 1.1.1.21; AR, ALR2), and sorbitol dehydrogenase (EC 1.1.1.14; SDH, SORD) have been widely investigated as the enzymes crucially involved in the pathogenesis of several chronic complications, including nephropathy, neuropathy, retinopathy, and cataracts associated with diabetes mellitus. Although phenolic compounds have been reported to possess many other biological activities, in continuation of our interest in designing and discovering potent inhibitors of AR and SDH, herein, we have evaluated these agents' inhibitory potential against polyol pathway enzymes. Our in vitro studies revealed that all the derivatives show activity against recombinant human AR (rhAR) and SDH (rhSDH), with KI constants ranging from 9.37±0.16 μM to 77.22±2.49 μM and 2.51±0.10 μM to 42.16±1.03 μM, respectively. Among these agents, Prunetin and Phloridzin showed prominent inhibitory activity versus rhAR and rhSDH, while some were also determined to possess perfect dual activity. Moreover, in silico studies were also performed to rationalize binding site interactions of these agents with the target enzyme AR and SDH. According to ADME‐Tox was also determined that these derivatives be agents exhibiting suitable drug‐like properties. The compounds identified therapeutic potentials in this study may be promising for developing lead therapeutic agents to prevent polyol pathway complications. [ABSTRACT FROM AUTHOR]

Detergents have been major contributors to membrane‐protein structural study for decades. However, membrane proteins solubilized in conventional detergents tend to aggregate or denature over time. Stability of large eukaryotic membrane proteins with complex structures tends to be particularly poor, necessitating development of novel detergents with improved properties. Here, we prepared a novel class of detergents, designated 3,4‐bis(hydroxymethyl)hexane‐1,6‐diol‐based maltosides (HDMs). When tested on three membrane proteins, including two G‐protein‐coupled receptors (GPCRs), the new detergents displayed significantly better behaviors compared with DDM. Moreover, the HDMs were superior or comparable to LMNG, an amphiphile widely used for GPCR structural study. An optimal balance of detergent rigidity vs. flexibility of the HDMs is likely responsible for their favorable behaviors toward membrane‐protein stability. Thus, the current study not only introduces the HDMs, with significant potential for membrane‐protein structural study, but also suggests a useful guideline for designing novel detergents for membrane‐protein research. [ABSTRACT FROM AUTHOR]

Aberrant glucose homeostasis is the most common metabolic disturbance affecting one in ten adults worldwide. Prediabetic hyperglycemia due to dysfunctional interactions between different human tissues, including pancreas and liver, constitutes the largest risk factor for the development of type 2 diabetes. However, this early stage of metabolic disease has received relatively little attention. Microphysiological tissue models that emulate tissue crosstalk offer emerging opportunities to study metabolic interactions. Here, a novel modular multitissue organ‐on‐a‐chip device is presented that allows for integrated and reciprocal communication between different 3D primary human tissue cultures. Precisely controlled heterologous perfusion of each tissue chamber is achieved through a microfluidic single "synthetic heart" pneumatic actuation unit connected to multiple tissue chambers via specific configuration of microchannel resistances. On‐chip coculture experiments of organotypic primary human liver spheroids and intact primary human islets demonstrate insulin secretion and hepatic insulin response dynamics at physiological timescales upon glucose challenge. Integration of transcriptomic analyses with promoter motif activity data of 503 transcription factors reveals tissue‐specific interacting molecular networks that underlie β‐cell stress in prediabetic hyperglycemia. Interestingly, liver and islet cultures show surprising counter‐regulation of transcriptional programs, emphasizing the power of microphysiological coculture to elucidate the systems biology of metabolic crosstalk. [ABSTRACT FROM AUTHOR]

Methane (CH4) is inexpensive, high in heating value, relatively low in carbon footprint compared to coal, and thus a promising energy resource. However, the locations of natural gas production sites are typically far from industrial areas. Therefore, transportation is needed, which could considerably increase the sale price of natural gas. Thus, the development of distributed, clean, affordable processes for the efficient conversion of CH4 has increasingly attracted people's attention. Among them are plasma technology with the advantages of mild operating conditions, low space need, and quick generation of energetic and chemically active species, which allows the reaction to occur far from the thermodynamic equilibrium and at a reasonable cost. Significant progress in plasma‐assisted reforming of methane (PARM) is achieved and reviewed in this paper from the perspectives of reactor development, thermal and nonthermal PARM routes, and catalysis. The factors affecting the conversion of reactants and the selectivity of products are studied. The findings from the past works and the insight into the existing challenges in this work should benefit the further development of reactors, high‐performance catalysts, and PARM routes. [ABSTRACT FROM AUTHOR]

Aiming at a deep understanding of the reaction kinetics of gliding arc (GA) plasma reforming, a new approach to combining simulation and experiment is reported. By adding thermodynamic module and conservation equations of mass and energy into the conventional 0D plasma kinetics model, an effective link between experimental diagnostics and reaction kinetics simulation is established for dry reforming of CH4 in GA plasma. The GA plasma parameters are diagnosed experimentally as electron density of 1.4 × 1014 cm−3, electron temperature of 1.5 eV, and arc gas temperature of 2500 K. The kinetics simulation is implemented based on the obtained plasma parameters and verified by the online analysis of gaseous products. Consequently, the reaction mechanism is revealed by the reliable model. [ABSTRACT FROM AUTHOR]

Recently, low‐resistance to sintering and carbon deposition used in dry reforming of methane (DRM) limits their industrial application. In this study, we synthesized the better anti‐carbon deposition performance of a novel Ni/SiO2 catalyst which has hierarchical porous flower‐like structure by hydrothermal method. A series of characterizations were carried out by different test methods, and the results confirmed that the material had typical hierarchical porous structure, high specific surface areas, and strong metal‐support interaction. The catalyst activity tests at 700 °C in 40 h reaction manifested that CO2 and CH4 conversions of the flower‐like structure of Ni/SiO2 (F‐Ni/SiO2) (87.44% and 79.56%) are higher than that of Ni/SiO2 by the conventional impregnation method (C‐Ni/SiO2) (71.79% and 62.30%). The main reasons can be explained that the large specific surface area, Ni particles were well dispersed on the support surface, and the interaction between the active metal and support of the flower‐like structure of F‐Ni/SiO2 catalyst, have better stability and catalytic performance. Meanwhile, the TG result also showed that the F‐Ni/SiO2 catalyst had better anti‐carbon deposition performance than the traditional catalyst, which leading to a higher catalytic activity. [ABSTRACT FROM AUTHOR]

Detergents are the most frequently applied reagents in membrane protein (MP) studies. The limited diversity of one‐head‐one‐tailed traditional detergents, however, is far from sufficient for structurally distinct MPs. Expansion of detergent repertoire has a continuous momentum. In line with the speculation that detergent pre‐assembly exerts superiority, herein we report for the first time cross‐conjugation of two series of monomeric detergents for constructing a two‐dimensional library of dimeric detergents. Optimum detergents stood out with unique preferences in the systematic evaluation of individual MPs. Furthermore, unprecedented hybrid detergents 14M8G and 14M9G enabled high‐quality EM study of transporter MsbA and NMR study of G protein‐coupled receptor A2AAR, respectively. Given the abundance of cross‐coupling chemistries, comprehensive diversity could be readily covered that would facilitate the finding of new detergents for the manipulation of thorny MPs and innovation of the functional and structural study in future. [ABSTRACT FROM AUTHOR]

In view of the unsatisfactory effect and major limitations of the style transfer of art works, this paper takes Chinese ink painting for the research subject. The obvious texture characteristics of Chinese ink painting are selected as the input of the Cycle Generative Adversarial Network (CycleGAN) model builder, and the relativistic evaluator is employed to improve the model loss function and the adversarial loss function. An improved art style transfer method of the CycleGAN model is proposed. The experiment shows that the improved CycleGAN model is efficient and feasible for style transfer. Compared with the traditional CycleGAN model, the proposed model performs better in GAN train and GAN test, with a higher average pass rate, which is an increase of nearly 10%. At the same time, with the increase of the number of iterations, the training time of the improved model is close to that of the original model, but the image of the improved model training is larger, which shows that it has more advantages. [ABSTRACT FROM AUTHOR]

Background. Fracture continues to be a major public health concern in many parts of the developing world that results in several consequences and complications including lifelong morbidity and mortality. This study aimed to assess clinical outcomes of patients following fracture in Debre Markos Comprehensive Specialized Hospital, North West Ethiopia. Methods. An institution-based prospective cohort study was conducted from November 2020 to July 2021 among 207 fracture patients (69 visited traditional bone setter and 138 did not visit traditional bone setter). Data were collected through face-to-face interviews, physical examinations, and radiological investigations. Data were entered using Epi-Data version 3.1 and analysis was done using STATA 14 statistical software. Descriptive statistics were summarized using mean, median, standard deviation, and percentage and presented in tables and figures. The generalized linear model was fitted to identify the risks of the outcome variable. Risk Ratio with its 95% confidence interval was used and factors with a P-value less than 0.05 were considered as a statistically significant association. Result. The mean age of the participants was 37.5 ± 13.6 years and two-thirds of the participants were males. Nearly half of the patients 92 (44%), 50 (54%) from the exposed and 42 (46%) from the nonexposed group, were delayed getting treatment from the hospital. The majority of the patients had been treated with Plaster of Paris immobilization (55%) followed by fixation (15%) and a combination of both (12%). Nearly half of the participants (48%), 74% from the exposed and 35% from the nonexposed group, developed complications during the follow-up period. The commonest complication was joint stiffness (45%) followed by osteoarthritis (21%). The risk of fracture-related complications among patients who did not visit traditional bone setter was decreased by 54% as compared to visitors (RR 0.46; 95% CI: (0.35, 0.60)) Conclusion. The magnitude of complications following the fracture is found to be high and the risk of complications among patients who visited traditional bone setters increased significantly. Therefore, prevention measures should be strengthened and integration between hospitals and traditional bone setters should be made so that basic training on fractures management will be given. [ABSTRACT FROM AUTHOR]

Membrane proteins are of biological and pharmaceutical significance. However, their structural study is extremely challenging mainly due to the fact that only a small number of chemical tools are suitable for stabilizing membrane proteins in solution. Detergents are widely used in membrane protein study, but conventional detergents are generally poor at stabilizing challenging membrane proteins such as G protein‐coupled receptors and protein complexes. In the current study, we prepared tandem triazine‐based maltosides (TZMs) with two amphiphilic triazine units connected by different diamine linkers, hydrazine (TZM−Hs) and 1,2‐ethylenediamine (TZM−Es). These TZMs were consistently superior to a gold standard detergent (DDM) in terms of stabilizing a few membrane proteins. In addition, the TZM−Es containing a long linker showed more general protein stabilization efficacy with multiple membrane proteins than the TZM−Hs containing a short linker. This result indicates that introduction of the flexible1,2‐ethylenediamine linker between two rigid triazine rings enables the TZM−Es to fold into favourable conformations in order to promote membrane protein stability. The novel concept of detergent foldability introduced in the current study has potential in rational detergent design and membrane protein applications. [ABSTRACT FROM AUTHOR]

Ni‐based catalysts for dry reforming of methane (DRM) are prone to suffer from deactivation caused by carbon deposition and sintering. Pyrochlore (typically A2B2O7) is a thermostable material with substantial redox capacity, which makes it suitable as a support for Ni‐based DRM catalysts. Here we demonstrated that by adjusting the Zr/Ce ratio in the B‐site of the La2(CeZrNi)2O7 (10 wt.% Ni loading), its structural order could be significantly altered. With decreasing Zr/Ce ratio, the structure of the catalysts became less ordered with a phase transformation from pyrochlore (La2Zr2O7) to defective fluorite (La2Ce2O7). Meanwhile, a second phase La2NiZrO6/LaNiO3 other than pyrochlore was formed for each sample. By tuning the structure, samples presented different properties and XPS results illustrated that the compositions of the surface oxygen species of samples were significantly different. Catalysts possessing more oxygen vacancies displayed evidently enhanced coke resistance. Among all five catalysts, LNZ3C1 exhibited the highest activity, stability and carbon deposition resistance, which could be attributed to the most oxygen vacancies, the strongest nickel‐carrier interaction, and the best particle size distribution of it. [ABSTRACT FROM AUTHOR]

The development of efficient catalysts is pivotal for pollution abatement to guarantee a sustainable and green industrial production. Supported single atom catalysts (SACs) with the advantages of maximum atom utilization, unique electronic structure, and distinguished metal support interaction have recently become a hotspot in the catalysis community, and bring new opportunities for environmental catalysis. This review aims to provide a comprehensive overview of the latest progress on the environmental SACs from both the fundamental and practical points of view. It starts with highlighting the state‐of‐the‐art synthesis strategies of great values for the practical use to construct challenging SACs. The applications of SACs in the environmental remediation processes are critically summarized, including CO oxidation, NOx decomposition, volatile organic compounds incineration, CO2 conversion, and water purification. Meanwhile, the topic also sketches out the recent progress for the non‐mercury catalyzed acetylene hydrochlorination reaction to address the environmental‐benign synthesis. Emphasis is placed on the elucidation of the structure–activity relationships and the underlying catalytic mechanisms to shed light on the guidelines for catalyst optimization and upgradation. Finally, the remaining challenges and perspectives for this flourishing field are also discussed. [ABSTRACT FROM AUTHOR]

Dry reforming of CH4/CO2 provides an attractive route to convert greenhouse gas into syngas; however, the resistance to sintering and coking of catalyst remains a fundamental challenge at high operation temperatures. Here we create active and durable metal–oxide interfaces in porous single‐crystalline (PSC) CeO2 monoliths with in situ exsolved single‐crystalline (SC) Ni particles and show efficient dry reforming of CH4/CO2 at temperatures as low as 450 °C. We show the excellent and durable performance with ≈20 % of CH4 conversion and ≈30 % of CO2 conversion even in a continuous operation of 240 hours. The well‐defined active metal–oxide interfaces, created by exsolving SC Ni nanoparticles from PSC NixCe1−xO2 to anchor them on PSC CeO2 scaffolds, prevent nanoparticle sintering and enhance the coking resistance due to the stronger metal–support interactions. Our work would enable an industrially and economically viable path for carbon reclamation, and the technique of creating active and durable metal–oxide interfaces in PSC monoliths could lead to stable catalyst designs for many challenging reactions. [ABSTRACT FROM AUTHOR]

Water deficit stress severely threatens crop yield and numerous reports have shown silicon could enhance plants resistance to water deficit. One of the most important mechanisms is that silicon maintains the water balance. In this review, we summarized advanced research to elucidate the effect of silicon on plant water transport processes, including leaf water loss, vessel water transport, and root water uptake. In leaves, the deposition of silica phytolith on cuticle and stomata decreases transpirational water loss under water deficit stress. However, accumulating evidence suggest that silicon maintaining leaf water content is not through reducing water loss, but through osmotic adjustments, enhancing water transport and uptake. Enhancement of stem water transport efficiency by silicon is due to silica phytolith depositing in the cell wall of vessel tubes and pits, which support it avoiding to collapse and embolism, respectively. The improvement of root water uptake capacity by silicon acts as a key role in maintaining water balance. The underlying mechanisms include (i) enlargement of the root water uptake area, (ii) improvement of the water driving force, (iii) the prevention of water loss from root to soil, and (iv) the up‐regulation of aquaporin activity. This review provides three simple models to understand the mechanism of silicon on water balance and highlights the future research area. [ABSTRACT FROM AUTHOR]

A novel ammonia vapour diffusion‐assisted impregnation technique was developed to synthesize the Al2O3‐MgO‐supported hierarchical Ni nanosheets. The resulting catalysts with different times for ammonia vapour treatments (at 12, 18, and 20 hours) were prepared to investigate the growth of Ni nanosheets on the catalyst surface. All catalysts were tested for CO2 reforming of methane and a comprehensive characterization study was conducted by XRD, N2 adsorption‐desorption, H2‐TPD, H2‐TPR, CO2‐TPD, and TGA. The Ni nanosheets were obtained using the ammonia vapour treatment for 20 hours, improving the selectivity toward H2 generation without a lower CH4 conversion. When compared to the reference catalyst prepared by a conventional impregnation method, the H2/CO ratio for CO2 reforming of the methane process was enhanced by 0.35. Additionally, the carbon deposition was reduced by half using hierarchical Ni nanosheets for the CO2 reforming of methane at 620°C for 20 hours. The mechanism of this improvement was achieved by the increase in medium basicity associated with a strong metal‐support interaction that promotes the CO2 activation‐dissociation pathways, preventing carbon formation and inhibiting the reverse water gas shift. [ABSTRACT FROM AUTHOR]

In the present paper, an optimization model is proposed for the ammonia synthesis reactor. The reversible exothermic reaction has nitrogen and hydrogen as reactants, at high temperatures, and high pressures with iron catalyst. Two different single‐objective optimization problems were considered, the maximization of the economic return and the maximization of the nitrogen conversion. The reaction rate model was defined as a function of partial pressures of the components. The problem was coded and solved in MATLAB using a derivative‐free method after reformulating a constrained optimization problem into an unconstrained one, by penalizing the infeasibilities of the constraints in the objective functions (barrier function). The main contributions of this paper are the combination of direct‐search methods in solving the optimization problem, the evaluation of the maximum ammonia production and the temperature profile. The optimal values found were better than the ones published in the literature. [ABSTRACT FROM AUTHOR]

Conversion of CO2 into useful chemical feedstocks or fuels using solar energy is a promising technology to tackle both climate change and energy shortage challenges. Here, NiCo alloys derived from AlMg hydrotalcite are introduced for photothermal synergetic CO2 conversion with CH4 with an ultrahigh light‐to‐fuel efficiency of 33.8% and a low carbon deposition rate of 0.011 gc g−1cat h−1. The ultrahigh efficiency is attributed to the high solar absorptance of NiCo alloys, unique synergistic catalysis of NiCo active sites, and the photo‐enhanced reactant activation. Inhibition of carbon formation lies in concurrent reduced energy barriers of CH* oxidation to CHO* and increased energy barriers of CH* dissociation to C*, enabled by the unique synergistic catalysis of NiCo alloys. Direct light illumination results in an obvious decrease of the apparent activation energy of CO2 conversion with CH4, making light‐driven CO2 conversion superior to conventional thermal‐driven techniques. Herein, a new platform for achieving efficient solar‐driven CO2 conversion with ultrahigh light‐to‐fuel efficiency based on NiCo alloy catalyst is provided and the way for sclable deployment of photothermal CO2‐to‐fuel techniques is paved. [ABSTRACT FROM AUTHOR]

Sintering of active Ni sites and deposition of coke remain challenging issues for catalytic dry reforming of methane. Herein, Ni supported on the Sn‐incorporated MCM‐41 catalysts were synthesized and tested for DRM process. The structural and physicochemical properties of fresh and spent samples were studied by N2 adsorption‐desorption, XRD, H2‐TPR, XPS, TEM, STEM‐EDS, Raman, and TGA techniques. It was revealed that Sn addition improved the dispersion and decreased the size of active Ni nanoparticles by tuning the charger transfer between Ni and Sn. The formation of Ni−SnOx interface provides more possibilities to activate CO2. The best results were obtained by 2Ni/Sn−MCM‐41 sample with the Ni/Sn mole ratio of 2 : 1, contributing CH4 conversion of 95% and CO2 conversion of 94% at 800 °C. Moreover, the presence of Sn increased the resistance to sintering of Ni‐based catalysts during the severe conditions, thereby the Ni nanoparticle size only appeared a slight growth after 32 h TOS. Combined with the characterization of the spent 2Ni/Sn−MCM‐41 sample, it was revealed that the coke deposition of the deactivated catalyst was dominated by amorphous carbon, which could be responsible for the desirable regeneration ability of the catalyst. [ABSTRACT FROM AUTHOR]

Herein, the synthesis of pure and modified mesoporous nanocrystalline NiO is reported. The catalyst was modified with different wt % F‐ions or K2O and used to produce Methyl ethyl ketone (MEK) as a potential fuel/solvent. XRD analysis of the promoted catalysts confirmed the formation of Ni‐metal covered by the host oxide, compared with pure NiO, especially for the promoted catalysts with x wt % F‐ions. CO2‐TPD results demonstrated the existence of different basic sites over these catalysts with varying strength. The catalytic conversion of sec‐butanol (SB) into MEK over the parent NiO catalyst showed 52 % and 76.8 % conversion of SB at 250 and 275 °C, respectively, with higher selectivity to MEK >96 %. Among the promoted catalysts, NiO‐10 wt % F− and NiO‐1 wt % K2O catalysts showed 99 and 95 % conversion, respectively, with retaining the MEK selectivity of ≥96 %. The catalytic activity, of the most active catalysts, was correlated with the presence of Ni/NiO interfaces, different types of basic sites, especially strong basic sites, and the surface area and porosity measurements. [ABSTRACT FROM AUTHOR]

Objective. Insulin resistance (IR) is closely associated with metabolic profiles, including obesity and dyslipidemia. The aim of the present study was to examine how lipid profiles were associated with IR in nonobese middle-aged and elderly Chinese population. Methods. This cross-sectional study included 1608 subjects. IR was defined by homeostasis model assessment of insulin resistance (HOMA-IR) of at least 2.5. Results. In nonobese subjects (body mass index (BMI) < 25 kg/m2, n = 996), triglyceride (TG) to high-density lipoprotein cholesterol (HDL-C) ratio (odds ratio (OR) = 1.43, 95% confidence interval (CI) 1.13–1.81, P = 0.003) was an independent risk factor for IR. The best marker for predicting IR in nonobese subjects was TG/HDL-C ratio with the areas under the receiver operating characteristic curves (AUC) of 0.73 (P < 0.001). The optimal cut-off point to identifying IR for TG/HDL-C ratio was ≥1.50 in the nonobese population. Other markers like BMI, TG, and total cholesterol (TC)/HDL-C also had acceptable discriminatory power for predicting IR in nonobese population (AUC ≥ 0.7 and P < 0.001). BMI had the highest AUC of 0.647 (P < 0.001) after being adjusted, but it was not effective enough to predict IR in obese subjects (BMI ≥ 25.0, n = 612). Conclusions. The TG/HDL-C ratio may be the best reliable marker for predicting IR in the nonobese middle-aged and elderly Chinese population. [ABSTRACT FROM AUTHOR]

Nitroxide mediated polymerization (NMP), sometimes known as stable free radical polymerization (SFRP), is considered one of the main types of reversible deactivation radical polymerization (RDRP) that have emerged as a major advance in polymer synthesis in the past 30 years. This review examines NMP's development from a uniquely Canadian perspective. Inspired by reports of a reversible equilibrium between the TEMPO persistent radical and a growing polymeric radical chain, researchers at the Xerox Research Centre of Canada (XRCC) reported radical polymerizations of styrene with hallmarks typically associated with living polymerizations: linear degree of polymerization of with conversion, narrow molecular weight distributions, and ability to re‐initiate the chain end with additional monomer. This effort expanded to polymerizations in dispersed aqueous media (eg, miniemulsion) and to polymerizations directed for various architectures (block, graft, star), but NMP was ultimately generally limited to styrenic monomers. Consequently, NMP trailed other RDRP methods, such as atom transfer radical polymerization (ATRP) and reversible addition fragmentation transfer polymerization (RAFT), due to its limited monomer choice. With the advent of second‐generation alkoxyamine initiators, however, the range of monomers polymerizable in a controlled manner greatly expanded to include acrylates, acrylamides, and eventually methacrylates (under certain conditions), providing renewed impetus towards using NMP. Consequently, Canadian researchers applied these new alkoxyamines for more versatile polymers, resulting in products such as stimuli‐responsive polymers, CO2‐switchable latexes, bio‐hybrid composites, organic photovoltaic materials, and photolithographic materials. The chronological progression of the developments in NMP from various Canadian laboratories highlights these achievements in new polymeric materials. [ABSTRACT FROM AUTHOR]

Dry reforming of methane (DRM) over Ni/γ‐MgO catalysts in a coaxial dielectric barrier discharge (DBD) reactor was investigated and compared with DRM without catalysts. Firstly, the catalysts Ni/MgO, Ni/5%CeO2/MgO, and Ni/7%CeO2/MgO were prepared, their characteristics were specified by X‐ray diffraction, and then, they were partially packed into the DBD reactor. Various parameters such as the discharge power, flow rate, and CH4/CO2 molar ratio were explored. The presence of catalysts in the plasma reactor increased the yield and selectivity of H2 and CO. Furthermore, the effect of a reduced catalyst (Ni/7%CeO2/MgO reduced in argon‐hydrogen plasma) was evaluated, showing that CH4 can be converted with activated catalyst without extra power. Activated Ni/7%CeO2/MgO alone was able to convert CH4 to over 99 % for 30 min after reduction. [ABSTRACT FROM AUTHOR]

Thermocatalyatic decomposition (TCD) of methane to COX free hydrogen and carbon nanofibre (CNF) was investigated over a series of self‐designed monometallic Ni catalyst and bimetallic Ni−Cu and Ni−Pd catalysts. The catalysts were synthesised from the wet impregnation method and characterised using a series of complementary techniques include TGA, XRD, BET, TPR, FESEM, TEM, and Raman Spectroscopy. Despite a substantial reduction of surface area in the promoted catalysts, the catalytic activity of the promoted catalyst was enhanced due to the nature of the process which is a metal‐catalysed reaction. As a whole, bimetallic Pd−Ni catalyst with a surface area of 2.76 m2 g−1 possesed the highest conversion of 77 % after 6 h reaction. The overall TCD reaction was found to be first‐order with the calculated activation energy, Ea of 38 kJ mol−1. The methane consumption rates at 1023 K and 1073 K were 0.5 mol s−1gcat−1 and 0.58×104 mol s−1gcat−1 respectively. Meanwhile, the methane consumption rates improved considerably from 0.58 mol s−1gcat−1 to 0.67×104 mol s−1gcat−1 under the methane partial pressure of 41 kPa. The XRD profile of the fresh catalysts revealed that mixed oxides were formed over the surface of the support upon the addition of Cu and Pd to 50 %Ni/Al2O3. Moreover, the formation of carbon nanofibers followed both tip and base growth mechanisms as evident from the TEM images. Larger and wider carbon fibres were found in the Pd promoted catalyst. [ABSTRACT FROM AUTHOR]

The current study reviews the recent development in the direct conversion of methane into syngas, methanol, light olefins, and aromatic compounds. For syngas production, nickel‐based catalysts are considered as a good choice. Methane conversion (84%) is achieved with nearly no coke formation when the 7% Ni‐1%Au/Al2O3 catalyst is used in the steam reforming of methane (SRM), whereas for dry reforming of methane (DRM), a methane conversion of 17.9% and CO2 conversion of 23.1% are found for 10%Ni/ZrOx MnOx/SiO2 operated at 500 °C. The progress of direct conversion of methane to methanol is also summarized with an insight into its selectivity and/or conversion, which shows that in liquid‐phase heterogeneous systems, high selectivity (>80%) can be achieved at 50 °C, but the conversion is low. The latest development of non‐oxidative coupling of methane (NOCM) and oxidative coupling of methane (OCM) for the production of olefins is also reviewed. The Mn2O3–TiO2–Na2WO4/SiO2 catalyst is reported to show the high C2 yield (22%) and a high selectivity toward C2 (62%) during the OCM at 650 °C. For NOCM, 98% selectivity of ethane can be achieved when a tantalum hydride catalyst supported on silica is used. In addition, the Mo‐based catalysts are the most suitable for the preparation of aromatic compounds from methane. [ABSTRACT FROM AUTHOR]

An Al‐containing MIL‐53 metal‐organic framework with very high surface area (SBET=1130 m2.g−1, N2 sorption) was used as sacrificial template to prepare a nickel‐alumina‐based catalyst (Ni0AlMIL) highly active and stable in the reaction of dry reforming of methane (DRM). The procedure consisted in impregnating the activated (solvent free) MIL‐53 sample with a nickel precursor solution, then calcining the material to remove the organic linkers and subsequently reducing it to form the reduced nickel active phase. At the step of calcination, this procedure results in the formation of a porous uniform spinel phase with Ni nanospecies embedded in the alumina‐based matrix, as deduced from XRD, TPR and TEM analyses. This leads after reduction to a porous lamellar γ‐Al2O3 material with small Ni0 nanoparticles homogeneously dispersed and stabilized within the support. The performances of this catalyst in DRM are better than those of two reference Ni/alumina catalysts prepared for comparison by conventional nickel impregnation of two preformed alumina supports: a first one obtained by calcination of MIL‐53 (AlMIL) and a second one consisting of a commercial γ‐Al2O3 batch (AlCOM). Under steady state conditions at a temperature of 650 °C and a pressure of 1 bar, the higher CH4 and CO2 conversions (till 3 times higher than on Ni0/AlCOM), high catalytic stability (no loss of activity after 13–100 h) and higher selectivity towards DRM (H2:CO products ratio remaining at 1) on Ni0AlMIL compared to the other catalysts is believed to come from the particularly strong interaction between the nickel and alumina phases generated by using the unique high specific surface of the parent MOF support to deposit nickel. This creates an intimate mixing favorable to a persisting interaction of the nickel nanoparticles with the alumina support in the reduced material. The lamellar shape of the γ‐Al2O3 composing the catalyst and its remaining high specific surface may also contribute to the excellent Ni resistance to sintering and in turn to the inhibition of carbon nanotubes formation during the reaction. [ABSTRACT FROM AUTHOR]

The parameter sensitivity analysis of a hydraulically interconnected suspension (HIS) system shows that the sensitivity of the vibration responses in the bounce and roll modes to the hydraulic parameters are complementary. A novel HIS-based semiactive control method was thereby proposed to improve ride comfort and antiroll performance. In addition, the classic sky-hook max-min damping switched strategy provides significant benefits around the body resonance, but otherwise performs similarly to, or sometimes even worse than, passive suspension. Therefore, a dual-frequency-range switching strategy, which has optimal max-min damping in both frequency ranges, was developed for improving the ride comfort in a wider frequency bandwidth. In this study, a 9-DOF HIS system dynamics model was established, and the hydraulically interconnected subsystem model was validated experimentally. Subsequently, the elastic and damping characteristics of the hydraulically interconnected subsystem, as well as the parameter sensitivity in bounce mode and roll mode, were analyzed. Next, the sensitive parameters were optimized under sinusoidal excitation at various frequencies, and a frequency-range selector used to determine the excitation frequency range and adjust the shock absorber damping was designed. Finally, simulations in the frequency domain and time domain show that the proposed HIS-based semiactive dual-frequency-range switching control suspension improves the ride comfort in a wider frequency bandwidth and enhances the antiroll performance in the transient and steady steering process. [ABSTRACT FROM AUTHOR]

The dry reforming of shale gas (methane and ethane with an average ratio of 4 : 1) with carbon dioxide (DRS) is considered to be a promising way to produce syngas, which widens the utilization of shale gas and mitigates carbon dioxide emission. In this paper, Ce modified Ni‐based catalysts were developed and the corresponding catalytic performances for DRS were investigated with a fixed bed reactor. Results showed that the catalyst containing 5 wt% of Ni and 5 wt% of Ce performed a best catalytic effect, including the selectivity of syngas and the carbon resistance performance, which is due to the good metal dispersion, strong interaction between Ni and Ce, and the formation of Ni‐CeOx solid solution. The electron transfer between Ni and Ce, substitution of Ni for Ce, and the sequential oxygen vacancies or defects, play significant roles in activating CH4, C2H6 and CO2. The conversion of reactant gas increased with temperature, while the selectivity of syngas is little affected with temperature. In addition, the desired catalyst containing 5 wt% of Ni and 5 wt% of Ce showed good stability in the long‐time operation, which indicates that the Ce modified Ni‐based catalyst is a promising one for the dry reforming of shale gas. High fives! The catalyst 5Ni‐5Ce exhibits the best catalytic performance in the dry reforming of shale gas and CO2. The introduction of Ce creates strong interaction between Ni and Ce, which enhances the electron transfer between them. And the substitution of Ni for Ce produces oxygen vacancies and defects, which can accelerate the adsorption and activation of the reactant gases molecule, further promoting the reaction. [ABSTRACT FROM AUTHOR]

Abstract: Dry reforming of methane has been systematically investigated over a series of x‐Co@SiO2‐y catalysts where x is the Co particle size ranging from 11.1 to 121.3 nm while y denotes the silica shell thickness ranging from 6.0 to 21.9 nm. Various techniques including TEM, XRD, H2‐TPR/‐TPD, XPS, BET, O2‐TPO, TG, and H2‐TPSR‐MS were employed to characterize physicochemical properties of catalysts. H2‐TPR and XPS results indicate that the core–shell interaction is dependent on the core size: the smaller the Co particle size is; the stronger the core–shell interaction. The investigations employing H2‐TRSR‐MS and XPS on the spent catalysts demonstrated that a fraction of metallic Co was re‐oxidized on a large‐core catalyst such as 121.3‐Co@SiO2‐72.2 during the reaction, and such oxidation leads to lower catalytic activity and stability. O2‐TPO results indicated that the catalyst with smaller core size caused significant coking. TG analysis together with TEM investigation on the used samples suggested that carbon deposition is notably core‐size‐dependent and responsible for deactivation of the small‐core catalyst. Among various core–shell structured catalysts, 27.8‐Co@SiO2‐14.3 showed superior activity and durability, owing to the well‐balanced property between coking and anti‐oxidation of Co cores. [ABSTRACT FROM AUTHOR]

ABSTRACT Rod-coil-rod triblock copolymers, poly[4′-(methoxy)-2-vinylbiphenyl-4-methyl ether] - blockpolydimethylsiloxane- block-poly[4′-(methoxy)-2-vinylbiphenyl-4-methyl ether] (PMVBP- b-PDMS- b-PMVBP), were synthesized by nitroxide-mediated radical polymerization, and their hierarchically ordered structures were studied. A difunctional TEMPO macroinitiator was first synthesized by the hydrosilylation reaction between hydride-endcapped PDMS and allylic alkoxyamine. The polymerization of the monomer MVBP was triggered by the macroinitiator, resulting in a series of triblock copolymers. The molecular weights and polydispersity indexes were determined by gel permeation chromatography. Differential scanning calorimetry results demonstrate that the triblock copolymers exhibit two glass transition temperatures (−120 °C and 160 °C) that are markedly different. As revealed by small-angle X-ray scattering and transmission electron microscopy experiments, the triblock copolymers self-assemble into hierarchical structures with the liquid crystalline phase of PMVBP in the lamellar structures. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1737-1744 [ABSTRACT FROM AUTHOR]

The Candida antarctica lipase B catalyzed transesterification of 2-(tetramethylpiperidine-1-oxyl)ethanols provides acetates in useful yields with good to high enantiomeric excess values. By taking advantage of the persistent radical effect, the remaining alcohols can be cleanly racemized under mild conditions in the presence of TEMPO [2,2,6,6-tetramethylpiperidin-1-yl)oxidanyl]. [ABSTRACT FROM AUTHOR]

The synthesis of polystyrene (PS) brushes on fully deuterated PS nanoparticles by surface-initiated nitroxide-mediated radical polymerization (SI-NMRP) is reported. Due to the high demand of deuterated monomers, an efficient deuteration procedure of suitable and readily available precursors is developed. SI-NMRP of styrene is improved regarding reaction control, grafting density, and conversion. Insights into the scaling behavior and conformational features of surface-attached PS chains on deuterated particles are investigated by using dynamic light scattering measurements, proving that polymer brushes are formed. The particles with surface-attached initiator are shown to be uniform spherical core-shell particles by small-angle neutron scattering measurements. [ABSTRACT FROM AUTHOR]

The problem of controlling cascade systems, involving in series a saturating actuator and a linear plant, is revisited. Presently, the actuator is described with a more realistic model that accounts not only for its saturating nature but also for its dynamics. Furthermore, the considered model emphasises the internal feedback interaction (between saturation and dynamics) that characterises most real-life actuators. The control objective is 2-fold: (i) stabilising the whole actuator-plant association; (ii) and enforcing the plant input de accurately match any bounded reference signal. To this end, a two-loop controller is developed following a backstepping-like design procedure. Accordingly, the outer regulator is first synthesised, to meet the output-reference tracking objective. During this synthesis stage the actuator output is considered as a virtual control signal. The control law obtained at this stage will serve as a reference trajectory for the actuator output. In the second stage, the inner regulator is designed to make the actuator output tracks its reference trajectory. The cascade controller thus developed is formally shown to meet its control objectives, that is, bounded input bounded output (BIBO) stability and perfect asymptotic matching of any reference signal that is compatible with the actuator saturation. [ABSTRACT FROM AUTHOR]

High resolution petrophysical analyses were carried out on Urgonian (Lower Cretaceous) carbonates from outcrops in Provence, SE France. Porosity and permeability were measured on 541 plug samples selected from grain-supported carbonates analogous to those in the age-equivalent Shu'aiba and Kharaib Formation reservoirs in the eastern Arabian Plate. The sampling strategy allowed property heterogeneities from centimetre to kilometre scales to be investigated, as well as correlations between porosity and permeability in several different reservoir rock types. Property spatial modelling sensitivity analyses were also undertaken. The relative abundance of microporosity, grain size and sedimentary-diagenetic anisotropy were the main geological parameters which controlled the petrophysical characteristics of the grainstones studied. Increasing microporosity decreased permeability but resulted in an increase in the homogeneity of the reservoir rocks and therefore in their predictability. An increase in grain size, from fine sand to gravel, and in the amount of intergranular pores, enhanced permeability significantly but resulted in a decrease in the homogeneity (and therefore predictability) of the reservoir rock. At a plug scale, poro-perm relationships are very good and can be used predictively for fine grainstones dominated by microporosity; but relationships are moderate to weak for coarse rudstones with mixed pore types, including intraskeletal pores. In grainstone units, weak sedimentary anisotropy, such as decametre-scale cross-bedding, did not prevent the prediction of the horizontal property distribution from vertical data over a few hundreds of metres. In these units, the lateral correlation of rock properties follows periodic variograms with a 7 m wavelength. The lateral distribution of properties in coarse-grained and heterogeneous rudstones with complex pore types and intense sedimentary heterogeneities, such as channel structures, was however more difficult to predict from a vertical data set. Upscaling poroperm data from plug scale to reservoir scale is linear in the case of grainstones with intergranular microporosity, but is non-linear in the case of skeletal rudstones with coarser pore types including skeletal porosity. [ABSTRACT FROM AUTHOR]

CO2 reforming of methane (DRM) represents a viable process to convert the two major greenhouse gases (CO2 and CH4) into high‐value syngas. Nickel‐based catalysts are effective and economical for such a reaction, but they are limited by deactivation owing to sintering and coking. In this work, a one‐pot hydrothermal method is presented, whereby highly stable nano‐sized Ni particles combined with a highly dispersed Ca promoter is implemented over Ca–Ni–SiO2. The so‐produced catalyst shows excellent performance for DRM at temperature as low as 550 °C, with no deactivation observed after a 20‐h catalytic run. Further characterizations demonstrate that the nickel silicate precursor produces sintering‐resistant Ni particles with an average diameter of 3.6 nm, harboring substantial active sites and with relatively active carbon species. In addition, the high dispersion of Ca promoter significantly increases the adsorption of CO2, which enhances the elimination of carbon deposition. Such a synergistic effect derived from small‐sized Ni active sites and basic promoter remarkably increases activity and stability of the catalyst, and inhibits carbon deposition, with only 0.6% deposited carbon formed. [ABSTRACT FROM AUTHOR]