Search

Conventional asphalt pavement has a deep surface color and large thermal inertia, which leads to the continuous absorption of solar thermal radiation and the sharp rise of surface temperature. This can easily lead to the permanent deformation of pavement, as well as aggravate the urban heat island (UHI) effect. Cool pavement with a reflective coating plays an important role in reducing pavement temperature and alleviating the UHI effect. It is of great significance to study the influence of temperature on the mechanical response of different types of pavement under vehicle loading. Therefore, this study examined the heat exchange theory between pavement and the external environment and utilized the representative climate data of a 24 h period in the summer. Two kinds of three-dimensional finite element models were established for the analysis of temperature distribution and the mechanical responses of conventional pavement and cool pavement. The results show that in this environmental condition, conventional pavement temperatures can exceed 50 °C under high temperatures in summer, which allows for the permanent deformation of pavement and further affects the service life of asphalt pavement. The temperature difference in a conventional pavement surface between 6 h (24.7 °C) and 22 h (30.2 °C) is much less than that between 22 h (30.2 °C) and 13 h (50.1 °C) in the summer. However, the difference in the vertical displacements of the pavement surface between 6 h and 22 h is much larger than that between 22 h and 13 h. One reason is that the difference in temperature distribution between the morning and night leads to changes in pavement structure stiffness, resulting in significant differences in vertical displacement. Cool pavement has a significant cooling effect, which can reduce the surface temperature of a road by more than 15 °C and reduce the vertical displacement of the pavement by approximately 11.3%, which improves the rutting resistance of the pavement. However, the use of cool pavement will not change the horizontal strain at the bottom of the asphalt base and will not improve the fatigue resistance of asphalt pavement. This research will lay the foundation for further clarifying the difference in the mechanical properties between the two types of pavements in the management and maintenance stage. [ABSTRACT FROM AUTHOR]

This study presents a theoretical study on the super thin and conductive thermal absorber with built-in corrugated channels on the basis of previous field experiments. The flow and heat transfer characteristics of the corrugated channels are simulated to identify the factors affecting photovoltaic/thermal (PV/T) system efficiency. The influences of the structural parameters such as the corrugation number, the corrugation area, and the flow channel width on the water outlet temperature and heat collection are discussed in order to support the structural optimization design of the hybrid PV/T system. The simulation results were validated to be in good agreement with experimental results. The results indicate that increasing inlet water velocity leads to a decrease in the outlet temperature. It was found that the corrugation area and the flow channel width have impacts on the outlet temperature of the hybrid PV/T collector panel. When the flow channel width of the absorber plate is reduced from 4 mm to 3 mm, the outlet temperature attained is between 298 and 302 K, and the heat collection is in the range of 16.2–51.4 MJ/h. This led to an increase in the amount of heat collected by 18.6%. [ABSTRACT FROM AUTHOR]

[Display omitted] • A hybrid of Mo-WN coated with carbon shell and Co(OH) 2 is constructed successfully. • The hybrid shows the small η 100 of 148 mV and η 500 of 196 mV. • Co(OH) 2 and Mo doping endow the hybrid with an appropriate water dissociation energy. • Free energy diagram reveals Co(OH) 2 and Mo doping promote Volmer and Heyrovsky steps. Water electrolysis is currently the most important way to achieve large-scale hydrogen (H 2) production. Although many nonprecious electrocatalysts possess promising catalytic performance at low current density below 50 mA cm−2, it remains a substantial challenge to realize H 2 production at industry-compatible current density over 500 mA cm−2. Here we have designed a hierarchical heterostructure of molybdenum-doped tungsten nitride coated with carbon shell and cobalt hydroxide nanosheets (Mo-WN@NC@Co(OH) 2) for alkaline hydrogen evolution reaction (HER) with industrial current density and stability. The hybrid exhibits efficient alkaline HER activity, reaching the current density of 500 mA cm−2 at an overpotential of 196 mV. The Co(OH) 2 nanosheets and Mo doping endow the composite with more active sites and enhanced intrinsic activity of the catalyst, as well as an appropriate water dissociation energy. In addition, the free energy of activation for each step during the HER process suggests a synergistic effect of Mo doping and Co(OH) 2 in Mo-WN@NC@Co(OH) 2 promoting surface Volmer and Heyrovsky steps during the HER process. This doping and interfacial engineering methods hold great promise for fabricating efficient nitride-based electrocatalysts for electrochemical energy devices. [ABSTRACT FROM AUTHOR]

The interactions between SO 2 and natural salt aerosol particles represent complex and crucial dynamics within atmospheric processes and the broader climate system. This study investigated the SO 2 uptake, hygroscopicity, morphology and mixing states of natural salt particles, which are generated from brines sampled from the Chaka salt lake located in the Qinghai-Tibet plateau. A comparison with atomized pure NaCl particles is included as reference. The results show that NaCl particles exhibit the lowest SO 2 uptake, while Chaka salt particles demonstrate higher uptake due to their complex composition. The hygroscopicity of salt particles is influenced by several factors, including chemical complexity, SO 2 exposure and light conditions. In comparison to pure NaCl, Chaka salt displays higher hygroscopicity, which is further enhanced in the presence of SO 2. However, when exposed to light, mass growth is suppressed, suggesting the formation of species with lower hygroscopicity, such as Na 2 SO 4. Analysis of particle morphology and mixing states reveals notable distinctions between NaCl crystals and Chaka salt particles, where the Chaka salt particles exhibit rounded shapes with a structure composed of cubic NaCl cores surrounded by sulfate materials as a coating. In addition, the chemical morphology analysis also reveals that the particles show morphological and spectral changes before and after the exposure to SO 2 , light and high RH. Therefore, this research highlights the intricate interactions between SO 2 and natural salt aerosol particles in diverse environmental settings, underscoring their multifaceted impacts on atmospheric processes. • Natural salt particles show higher SO 2 uptake than pure NaCl particles. • The hygroscopicity is influenced by chemical complexity, SO 2 exposure, and light conditions. • Light exposure suppresses hygroscopic growth, potentially leading to the formation of less hygroscopic species. • Natural salt particles exhibit rounded shapes with cubic NaCl cores encased in sulfate coatings. • Particles exhibit morphological and spectral changes after exposure to SO 2 , light, and high RH. [ABSTRACT FROM AUTHOR]

Alkali species present in biomass pose significant challenges in chemical looping combustion (CLC) processes and other thermal conversion applications. The interactions between different alkali species and three common oxygen carrier (OC) materials that are considered to be state of the art in CLC applications have been investigated. A dedicated fluidized bed laboratory reactor was used to study interactions of KCl, NaCl, KOH, NaOH, K 2 SO 4 and Na 2 SO 4 with manganese oxide, calcium manganite and ilmenite. Alkali vapor was generated by injecting alkali salts under reducing, oxidizing and inert conditions at 900 °C. Gaseous species were measured online downstream of the reactor, and the efficiency of alkali uptake was determined under different conditions. The result show significant alkali uptake by all OCs under the studied conditions. Ilmenite shows near complete alkali uptake in reducing conditions, while manganese oxide and calcium manganite exhibited less effective alkali uptake, but have advantages in terms of fuel conversion and oxidizing efficiency. Alkali chlorides, sulfates and hydroxides show distinctly different behavior, with alkali hydroxides being efficiently captured all three investigate OC materials. The findings contribute to a deeper understanding of alkali behavior and offer valuable guidance for the design and optimization of CLC with biomass. [Display omitted] • Alkali uptake dynamics by OCs under CLC conditions • Uptake of sodium and potassium compounds by OC fluidized beds • Alkali interactions with ilmenite, calcium manganite and manganese oxide • Speciation of alkali emissions from fluidized bed CLC operation [ABSTRACT FROM AUTHOR]

A surface-promoted sulfate-reducing ammonium oxidation reaction was discovered to spontaneously take place on common inorganic aerosol surfaces undergoing solvation. Several key intermediate species—including elemental sulfur (S0), bisulfide (HS−), nitrous acid (HONO), and aqueous ammonia [NH3(aq)]—were identified as reaction components associated with the solvation process. Depth profiles of relative species abundance showed the surface propensity of key species. The species assignments and depth profile features were supported by classical and first-principles molecular dynamics calculations, and a detailed mechanism was proposed to describe the processes that led to unexpected products during salt solvation. This discovery revealed chemistry that is distinctly linked to a solvating surface and has great potential to illuminate current puzzles within heterogeneous chemistry. [ABSTRACT FROM AUTHOR]

High‐crystalline‐quality absorbers with fewer defects are crucial for further improvement of open‐circuit voltage (VOC) and efficiency of Cu2ZnSn(S,Se)4 (CZTSSe) solar cells. However, the preparation of high‐quality CZTSSe absorbers remains challenging due to the uncontrollability of the selenization reaction and the complexity of the required selenization environment for film growth. Herein, a novel segmented control strategy for the selenization environment, specifically targeting the evaporation area of Se, to regulate the selenization reactions and improve the absorber quality is proposed. The large evaporation area of Se in the initial stage of the selenization provides a great evaporation and diffusion flux for Se, which facilitates rapid phase transition reactions and enables the attainment of a single‐layer thin film. The reduced evaporation area of Se in the later stage creates a soft‐selenization environment for grain growth, effectively suppressing the loss of Sn and promoting element homogenization. Consequently, the mitigation of Sn‐related deep‐level defects on the surface and in the bulk induced by element imbalance is simultaneously achieved. This leads to a significant improvement in nonradiative recombination suppression and carrier collection enhancement, thereby enhancing the VOC. As a result, the CZTSSe device delivers an impressive efficiency of 13.77% with a low VOC deficit. [ABSTRACT FROM AUTHOR]

Laboratory experiments are presented on the phase change at the surface of sodium chloride–water mixtures at temperatures between 259 and 241 K. Chloride is a ubiquitous component of polar coastal surface snow. The chloride embedded in snow is involved in reactions that modify the chemical composition of snow as well as ultimately impact the budget of trace gases and the oxidative capacity of the overlying atmosphere. Multiphase reactions at the snow–air interface have been of particular interest in atmospheric science. Undoubtedly, chemical reactions proceed faster in liquids than in solids; but it is currently unclear when such phase changes occur at the interface of snow with air. In the experiments reported here, a high selectivity to the upper few nanometres of the frozen solution–air interface is achieved by using electron yield near-edge X-ray absorption fine-structure (NEXAFS) spectroscopy. We find that sodium chloride at the interface of frozen solutions, which mimic sea-salt deposits in snow, remains as supercooled liquid down to 241 K. At this temperature, hydrohalite exclusively precipitates and anhydrous sodium chloride is not detected. In this work, we present the first NEXAFS spectrum of hydrohalite. The hydrohalite is found to be stable while increasing the temperature towards the eutectic temperature of 252 K. Taken together, this study reveals no differences in the phase changes of sodium chloride at the interface as compared to the bulk. That sodium chloride remains liquid at the interface upon cooling down to 241 K, which spans the most common temperature range in Arctic marine environments, has consequences for interfacial chemistry involving chlorine as well as for any other reactant for which the sodium chloride provides a liquid reservoir at the interface of environmental snow. Implications for the role of surface snow in atmospheric chemistry are discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • The sulfidation fabricated a FeSx shell on microscale zerovalent iron (S-mZVI). • S-mZVI showed 98.1% removal of vanadium [V(V)], 98 times higher than mZVI. • V(V) removal by S-mZVI exhibited great applicability under various conditions. • V(V) removal was mainly mediated via reduction, adsorption, and precipitation. Sulfidation has been regarded as an effective strategy to enhance the sequestration of contaminants by zerovalent iron (ZVI). However, the effect of sulfidation on ZVI for V(V) removal has not been explored, and the mechanism has not been fully elucidated. Here, this study evaluated V(V) removal by sulfidated microscale ZVI (S-mZVI) and sufficiently ascertained its underlying mechanism. First, the sulfidation of mZVI was studied and the characterization confirmed a uniformly-distributed FeS x shell fabricated on mZVI. Then, applying S-mZVI for V(V) removal was tested as a function of S/Fe molar ratios, pH, dissolved oxygen, and common anions. The greatest removal (98.1%) of V(V) was achieved by S-mZVI prepared under S/Fe of 0.05, 98 times higher than that by mZVI. The decreased pH showed a positive effect and V(V) removal reached 100% at pH 3.0. The common anions (Cl−, SO 4 2−, NO 3 − and HCO 3 −) showed slight inhibition on V(V) removal. Finally, V(V) removal by S-mZVI was clarified to be mediated via a combined function of reduction from V(V) to V(IV) and V(III), adsorption, and precipitation. These findings provided valuable insights into applying ZVI materials for V(V) removal. [ABSTRACT FROM AUTHOR]

Alkali compounds are readily released during biomass conversion and their complex interactions with reactor walls and sampling equipment makes detailed investigations challenging. This study evaluates a novel laboratory-scale fluidized bed reactor for chemical looping combustion (CLC) studies. The reactor design is based on detailed consideration of the behavior of alkali-containing molecules and aerosol particles and is guided by computational fluid dynamic simulations. The design allows for interactions between gaseous alkali and a fluidized bed, while minimizing alkali interactions with walls before and after the fluidized bed. The function of the laboratory reactor is demonstrated in experiments using online gas and alkali analysis. Alkali is continuously fed to the reactor as KOH or KCl aerosol with and without a fluidized bed of the oxygen carrier CaMn 0.775 Ti 0.125 Mg 0.1 O 3-δ present in inert, reducing and oxidizing conditions at temperatures up to 900 °C. Alkali uptake by the OC is characterized in all conditions, and observed to sensitively depend on gas composition, reactor temperature and type of alkali compound. The experimental setup is concluded to have a significantly improved functionality compared to a previously used reactor, which opens up for detailed studies of interactions between alkali compounds and oxygen carriers used in CLC. [Display omitted] • A novel reactor is designed for detailed alkali studies in CLC. • Based on CFD simulations and the behavior of aerosol particles. • The function of the reactor is demonstrated in typical CLC experiments. • Interactions between gaseous alkali and oxygen carriers are monitored online. • Greatly improved functionality compared to a previous CLC reactor. [ABSTRACT FROM AUTHOR]

Phase changes of sea salt particles alter their physical and chemical properties, which is significant for Earth's chemistry and energy budget. In this study, a continuous flow diffusion chamber is used to investigate deliquescence, homogeneous and heterogeneous ice nucleation between 242 K and 215 K, of four salts: pure NaCl, pure MgCl2, synthetic sea water salt, and salt distilled from sampled sea water. Anhydrous particles, aqueous droplets and ice particles were discriminated using a polarisation-sensitive optical particle counter coupled with a machine learning analysis technique. The measured onset deliquescence relative humidities agree with previous studies, where sea water salts deliquescence at lower humidities than pure NaCl. Deliquesced salt droplets homogenously freeze when the relative humidity reaches a sufficiently high value at temperatures below 233 K. From 224 K and below, deposition nucleation freezing on a fraction of NaCl particles was observed at humidities lower than the deliquescence relative humidity. At these low temperatures, otherwise unactivated salt particles deliquesced at the expected deliquescence point, followed by homogeneous freezing at temperatures as low as 215 K. Thus, the observed sea salt particles exhibit a triad of temperature-dependent behaviours. First, they act as cloud condensation particles (CCNs) > 233 K, second they can be homogeneous freezing nuclei (HFNs) < 233 K and finally they act as ice nucleating particles (INPs) for heterogeneous nucleation <224 K. [ABSTRACT FROM AUTHOR]

Background: Previous research has shown that lymphocytes and cytokines can mediate bone metabolism. This study explored the clinical association and predictive ability of lymphocytes and cytokines levels for bone metabolism. Methods: A total of 162 patients were enrolled in this study. The levels of N-terminal propeptide of type I procollagen (P1NP), β-collagen degradation product (β-CTX), total T lymphocytes, immature T lymphocytes, suppressor/cytotoxic T lymphocytes, helper/inducer T lymphocytes, B lymphocytes, natural killer (NK) cells, Interferon-gamma (IFN-γ), tumour necrosis factor-alpha (TNF-α), IFN-α, interleukin-1 beta (IL-1β), IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, and IL12p70 were evaluated. The relationship between these lymphocyte subsets and cytokines with bone metabolic status was examined and their predictive ability for bone metabolic status was assessed. Results: The principal component analysis (PCA) and correlation analysis results varied on differences in lymphocyte subsets and cytokines in various bone metabolism states. Differential analysis revealed significant differences in the absolute counts of B lymphocytes (P < 0.05), level of IL-12p70 (P < 0.05), and IL-8 (P < 0.001) at different P1NP levels. Significant differences were observed in the absolute counts of total T lymphocytes (P < 0.05), B lymphocytes (P < 0.05), the level of IL-6 (P < 0.05), the percentage of B lymphocytes (P < 0.01), and NK cells (P < 0.05) at different β-CTX levels. Furthermore, the receiver operating characteristic (ROC) curve showed that the absolute count of B lymphocytes and levels of IL-12p70 and IL-8 could be used to evaluate bone formation states, while the absolute counts of T and B lymphocytes, level of IL-6, and percentages of NK cells and B lymphocytes could be used to evaluate bone resorption states. Conclusion: The bone metabolism status changed based on the lymphocyte subsets and cytokine levels. Differentially expressed lymphocytes and cytokines could be used to distinguish bone metabolism status. [ABSTRACT FROM AUTHOR]

Leaf color variations in tea plants were widely considered due to their attractive phenotypes and characteristic flavors. The molecular mechanism of color formation was extensively investigated. But few studies focused on the transformation process of leaf color change. In this study, four strains of 'Baijiguan' F1 half-sib generation with similar genetic backgrounds but different colors were used as materials, including Green (G), Yellow-Green (Y-G), Yellow (Y), and Yellow-Red (Y-R). The results of broadly targeted metabolomics showed that 47 metabolites were differentially accumulated in etiolated leaves (Y-G, Y, and Y-R) as compared with G. Among them, lipids were the main downregulated primary metabolites in etiolated leaves, which were closely linked with the thylakoid membrane and chloroplast structure. Flavones and flavonols were the dominant upregulated secondary metabolites in etiolated leaves, which might be a repair strategy for reducing the negative effects of dysfunctional chloroplasts. Further integrated analysis with the transcriptome indicated different variation mechanisms of leaf phenotype in Y-G, Y, and Y-R. The leaf color formation of Y-G and Y was largely determined by the increased content of eriodictyol-7-O-neohesperidoside and the enhanced activities of its modification process, while the color formation of Y-R depended on the increased contents of apigenin derivates and the vigorous processes of their transportation and transcription factor regulation. The key candidate genes, including UDPG, HCT, CsGSTF1, AN1/CsMYB75, and bHLH62, might play important roles in the flavonoid pathway. [ABSTRACT FROM AUTHOR]

Objective: To tackle non-specific low back pain (NSLBP) among patients and find the most effective solution and to quantitatively synthesize the overall effect of motor control training (MCT) compared with Pilates, McKenzie method, and physical therapy (PT) in pain and physical function. Methods: Randomized controlled trials (RCTs) of four types of intervention (MCT, Pilates, McKenzie method, and PT) for LBP were collected by searching PubMed, Web of Science, EBSCOhost (Cochrane Central Register of Controlled Trials), and Scopus databases from the establishment of the database to September 30, 2023. The risk of bias was evaluated for included studies using the Revised Cochrane Risk of Bias tool for randomized trials (RoB 2.0). Taking pain and physical function in the experimental and control groups as outcome indicators, subgroup analysis was performed according to the intervention method to calculate the standardized mean difference (SMD) and 95% confidence interval (CI). Results: A total of 25 RCTs, including 1253 patients, were included. Meta-analysis showed that MCT effectively relieved pain [SMD = −0.65, 95% CI (− 1.00, − 0.29), p < 0.01] and improved physical function [SMD = −0.76, 95% CI (− 1.22, − 0.31), p < 0.01] comparing with other 3 types of intervention. Subgroup analysis suggested that MCT could alleviate pain [SMD = −0.92, 95% CI (− 1.34, − 0.50), p < 0.01] and improve physical function [SMD = −1.15, 95% CI (− 1.72, − 0.57), p < 0.01] compared with PT, but it had no statistical significance compared with Pilates [pain: SMD = 0.13, 95% CI (− 0.56, 0.83), p = 0.71; physical function: SMD = 0.10, 95% CI (− 0.72, 0.91), p = 0.81] and the McKenzie method [pain: SMD = −0.03, 95% CI (− 0.75, 0.68), p = 0.93; physical function: SMD = −0.03, 95% CI (− 1.00, 0.94), p = 0.95]. Conclusions: MCT can effectively relieve pain and improve physical function in patients with NSLBP. It is more effective compared with PT for LBP, while no differences were detected between MCT and Pilates, as well as McKenzie method. Therefore, MCT, Pilates, and the McKenzie method should be encouraged as exercise interventions for NSLBP rehabilitation. [ABSTRACT FROM AUTHOR]

Background Benign prostatic hyperplasia (BPH) most often occurs in older men; previous studies and clinical experience suggest a potential link between lifestyle habits such as sleep habits, sedentary behavior, exercise levels, and BPH, but whether they have a clear causal relationship and the direction of that causality is unclear. We aimed to investigate the causal relationship between lifestyle habits and BPH using 2-sample Mendelian randomization (MR) analysis. Methods Instrumental genetic independent variables strongly associated with the selected exposure factors were filtered from published genome-wide association studies (GWAS) consisting primarily of European ancestry samples. GWAS from BPH was analyzed as an MR outcome with the inverse-variance weighted method, maximum likelihood, weighted median method, MR–Egger regression, and several sensitivity analyses, including Cochran's Q test, intercept of MR–Egger, and MR pleiotropy residual sum and outlier test. Results MR analysis showed a significant causal risk relationship between sleep duration and BPH, with an odds ratio of 0.42 (95% confidence interval, 0.25–0.69, p =.001) for BPH when sleep duration was increased by 1 standard deviation, but we did not find a causal relationship between the 2 when we performed a reverse analysis. However, sedentary behavior and different levels of exercise did not significantly affect the risk of BPH. Conclusions This study showed a strong causal relationship between sleep levels and BPH, with adequate sleep duration being a protective factor for BPH. [ABSTRACT FROM AUTHOR]

The increasing penetration of distributed energy brings significant uncertainty and noises to microgrid operation, which enlarge the difficulty of microgrid monitoring. For as much as the detection of islanding is prone to be interfered by grid disturbance, island detection device may make misjudgment thus causing the consequence of distributed generations (DGs) out of service. The detection device must provide with the ability to differ islanding from grid disturbance. In this paper, the concept of deep learning is introduced into the classification of islanding and grid disturbance for the first time. A novel deep learning framework is proposed to detect and classify islanding or grid disturbance. The framework is a hybrid of wavelet transformation, multi-resolution singular spectrum entropy, and deep learning architecture. As a signal processing method after wavelet transformation, multi-resolution singular spectrum entropy combines multi-resolution analysis and spectrum analysis with entropy as output, from which we can extract the intrinsic different features between islanding and grid disturbance. With the features extracted, a deep learning based algorithm is proposed to classify islanding and grid disturbance. Simulation results indicate that the method can achieve its goal while being highly accurate, so the DGs mistakenly withdrawing from power grids can be avoided. [ABSTRACT FROM AUTHOR]

High-valence heavy metals with high ecotoxicity are generally found in water in the form of anions, and this increases heavy metal pollution intensity and treatment difficulty. Recent studies have pointed to the potential efficiency of layered double hydroxides (LDHs) to meet this challenge. In this review, we retrospectively research the development of LDHs using a Java application called CiteSpace. We describe the unique layer structure, highly adjustable chemical properties, and diverse synthesis methods of LDHs, all of which decide the effective adsorption of heavy metal anions by LDHs. Subsequently, we focus on discussing the adsorption mechanism of LDHs on heavy metal anions, as well as the current state of research and future directions for microscopic interaction mechanisms. For practical applications, it is critical to improve the adsorption selectivity and stability. We then recommend solutions to improve the adsorption selectivity and stability after identifying the influencing mechanism. Finally, we provide our perspectives on the future development of LDHs adsorption of heavy metal anions. [Display omitted] • A co-citation analysis of layered double hydroxides studied in environmental field is carried out. • Adjustable structural properties and diverse synthesis methods of layered double hydroxides are discussed. • Adsorption mechanism of LDHs on heavy metal anions is multifaceted and deserves further exploration. • Solutions to improve the heavy metal anion adsorption selectivity and stability of LDHs are summarized and recommended. [ABSTRACT FROM AUTHOR]

Water uptake on aerosol and cloudparticles in the atmosphere modifiestheir chemistry and microphysics with important implications for climateon Earth. Here, we apply an environmental molecular beam (EMB) methodto characterize water accommodation on ice and organic surfaces. Theadsorption of surface-active compounds including short-chain alcohols,nitric acid, and acetic acid significantly affects accommodation ofD2O on ice. n-Hexanol and n-butanol adlayers reduce water uptake by facilitating rapid desorptionand function as inefficient barriers for accommodation as well asdesorption of water, while the effect of adsorbed methanol is small.Water accommodation is close to unity on nitric-acid- and acetic-acid-coveredice, and accommodation is significantly more efficient than that onthe bare ice surface. Water uptake is inefficient on solid alcoholsand acetic acid but strongly enhanced on liquid phases including aquasi-liquid layer on solid n-butanol. The EMB methodprovides unique information on accommodation and rapid kinetics onvolatile surfaces, and these studies suggest that adsorbed organicand acidic compounds need to be taken into account when describingwater at environmental interfaces. [ABSTRACT FROM AUTHOR]

Adsorbed organic compounds modifythe properties of environmentalinterfaces with potential implications for many Earth system processes.Here, we describe experimental studies of water interactions withacetic acid (AcOH) layers on ice and graphite surfaces at temperaturesfrom 186 to 200 K. Hyperthermal D2O water molecules areefficiently trapped on all of the investigated surfaces, with onlya minor fraction that scatters inelastically after an 80% loss ofkinetic energy to surface modes. Trapped molecules desorb rapidlyfrom both μm-thick solid AcOH and AcOH monolayers on graphite,indicating that water has limited opportunities to form hydrogen bondswith these surfaces. In contrast, trapped water molecules bind efficientlyto AcOH-covered ice and remain on the surface on the observationaltime scale of the experiments (60 ms). Thus, adsorbed AcOH is observedto have a significant impact on water–ice surface propertiesand to enhance the water accommodation coefficient compared to bareice surfaces. The mechanism for increased water uptake and the implicationsfor atmospheric cloud processes are discussed. [ABSTRACT FROM AUTHOR]

The construction of a forming limit diagram (FLD) is a conventional approach to obtain limit strains and to evaluate the formability of sheet metal. Appropriate necking criteria should be applied to determine the forming limit curve (FLC) accurately. In recent years, deep research on the determination of the FLC has been carried out; meanwhile, several necking criteria have been proposed. However, the application of inappropriate necking criteria would cause deviations when determining FLCs. In this study, both Marciniak and Nakajima tests were carried out on the AA5086 aluminum sheet to make a comparative investigation of different necking criteria in the determination of FLCs. In the Marciniak test, four existing necking criteria were chosen to construct FLCs, and analyzed in detail. The well-performed time dependent and position dependent methods were selected for the Nakajima test. Meanwhile, the modified Wang method based on the height change of the adjacent points was proposed. The comparative results showed that the time and position dependent methods were relatively conservative in both experiments, while the modified Wang method could identify the onset of localized necking more accurately. [ABSTRACT FROM AUTHOR]

Modern small-scale biomass burners have been recognized as an important renewable energy source because of the economic and environmental advantages of biomass over fossil fuels. However, the characteristics of their gas and particulate emissions remain incompletely understood, and there is substantial uncertainty concerning their health and climate impacts. Here, we present online measurements conducted during the operation of a residential wood-burning boiler. The measured parameters include gas and particle concentrations, optical absorption and chemical characteristics of gases and particles. Positive matrix factorization was performed to analyze data from a high-resolution time-of-flight chemical ionization mass spectrometer (HR-ToF-CIMS) equipped with a filter inlet for gases and aerosols (FIGAERO). Six factors were identified and interpreted. Three factors were related to the chemical composition of the fuel representing lignin pyrolysis products, cellulose/hemicellulose pyrolysis products, and nitrogen-containing organics, while three factor were related to the physical characteristics of the emitted compounds: volatile compounds, semi-volatile compounds, and filter-derived compounds. An ordinal analysis was performed based on the factor fractions to identify the most influential masses in each factor, and by deconvoluting high-resolution mass spectra fingerprint molecules for each factor were identified. Results from the factor analysis were linked to the optical properties of the emissions, and lignin and cellulose/hemicellulose pyrolysis products appeared to be the most important sources of brown carbon under the tested burning conditions. It is concluded that the emissions from the complex combustion process can be described by a limited set of physically meaningful factors, which will help to rationalize subsequent transformation and tracing of emissions in the atmosphere and associated impacts on health and climate. Unlabelled Image • PMF analysis was applied to the CIMS data, which yields six well-interpreted factors. • Ordinal analysis enabled the automatic identification of the most characteristic molecules for each individual factors. • Correlations of factors and optical properties are discussed. [ABSTRACT FROM AUTHOR]

Alkali metal compounds are released during the thermal conversion of biofuels and fossil fuels and have a major impact on the efficiency of conversion processes. Herein, we describe a novel method for the simultaneous characterization of alkali release and mass loss from materials used in combustion and gasification processes including solid fuels, fluidized bed materials, and catalysts for gas reforming. The method combines the thermogravimetric analysis of selected samples with the on-line measurement of alkali release using a surface ionization detector. The technique builds on the careful treatment of alkali processes during transport from a sample to the downstream alkali monitor including the losses of alkali in the molecular form to hot walls, the formation of nanometer-sized alkali-containing particles during the cooling of exhaust gases, aerosol particle growth, and diffusion losses in sampling tubes. The performance of the setup was demonstrated using biomass samples and fluidized bed material from an industrial process. The emissions of alkali compounds during sample heating and isothermal conditions were determined and related to the simultaneous thermogravimetric analysis. The methodology was concluded to provide new evidence regarding the behavior of alkali in key processes including biomass pyrolysis and gasification and ash interactions with fluidized beds. The implications and further improvements of the technique are discussed. [ABSTRACT FROM AUTHOR]

• nZVI dispersed on layered double hydroxide (nZVI@LDH) was prepared. • nZVI@LDH performed best (93.7 mg g−1) with a nZVI/LDH mass ratio of 1:2 at pH 3. • The V(Ⅴ) was reduced and transformed into VO 2 and V 2 O 3 to reduce the desorption. • nZVI@LDH was an ideal scavenger for V(V)-contaminated groundwater. To reduce the toxicity of vanadium(V) [V(V)] and inhibit the desorption of adsorbed vanadium in groundwater, we synthesized nanoscale zerovalent iron (nZVI) dispersed on layered double hydroxide (LDH) composites (nZVI@LDH) to remove V(V) from simulated groundwater. We found that nZVI@LDH could reduce high-valence vanadium to low-valence vanadium, then forming vanadium-containing precipitation to reduce the toxicity and inhibiting vanadium from returning to groundwater. SEM and XRD characterizations exhibited the uniform dispersal of nZVI on the surface of LDH. nZVI@LDH with nZVI/LDH at a mass ratio of 1:2 provided the maximum adsorption capacity of 93.7 mg g−1 at pH 3.0. Coexisting anions and dissolved oxygen in groundwater have little effect on V(V) removal. nZVI@LDH performed well across a wide pH range (3.0–8.0). The surface characterizations and XPS analysis revealed that LDH as supporting materials inhibited the aggregation and passivation of nZVI. The adsorbed V(V) was reduced to V(IV) and V(III) by nZVI and spontaneously transformed into insoluble VO 2 and V 2 O 3. The DFT calculations indicated the strong complexation and better stability of the V(IV) and V(III) species with nZVI@LDH than V(V). This work suggests that nZVI@LDH has the potential to serve as an efficient material for the immobilization of V(V) in groundwater. [ABSTRACT FROM AUTHOR]

[Display omitted] • The role of alkali interacting with oxygen carrier particles in biomass combustion. • Alkali desorption from natural ilmenite oxygen carrier particles. • Effect of gas composition on desorption kinetics. • Characterization of particle surface layers using two spectroscopic methods. Oxygen-carrying fluidized bed materials are increasingly used in novel technologies for carbon capture and storage, and to improve the efficiency of fuel conversion processes. Potassium- and sodium-containing compounds are released during biomass combustion and may have both negative and positive effects on conversion processes. Ilmenite is an important oxygen carrier material with the ability to capture alkali in the form of titanates. This is a desirable property since it may reduce detrimental alkali effects including fouling, corrosion, and fluidized bed agglomeration. This study investigates the interactions of alkali-containing compounds with ilmenite particles previously used in an industrial scale (115 MW th) oxygen carrier aided combustion system. The ilmenite samples were exposed to temperatures up to 1000 °C under inert and oxidizing conditions while the alkali release kinetics were characterized using online alkali monitoring. Alkali desorption occurs between 630 and 800 °C, which is attributed to loosely bound alkali at or near the surface of the particles. Extensive alkali release is observed above 900 °C and proceeds during extended time periods at 1000 °C. The release above 900 °C is more pronounced under oxidizing conditions and approximately 9.1 and 3.2 wt% of the alkali content is emitted from the ilmenite samples in high and low oxygen activity, respectively. Detailed material analyses using scanning electron microscopy with energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy were conducted before and after temperature treatment, which revealed that the concentrations of potassium, sodium and chlorine decrease at the outermost surface of the ilmenite particles during temperature treatment, and Cl is depleted to a deeper level in oxidizing conditions compared to inert. The implications for ilmenite-ash interactions, oxygen carrier aided combustion and chemical looping systems are discussed. [ABSTRACT FROM AUTHOR]

1 at.% Ho3+, x at.% Tm3+: NaY 0.1 Gd 0.9 (WO 4) 2 (x = 1, 3, 5, 7, 9) crystals were successfully prepared by Czochralski method. The phase and optical properties of the crystals were analyzed by X-ray diffraction, absorption spectrum and photoluminescence spectrum. The tetragonal structure of the crystal that determined by the experimental data didn't be changed, and crystal had excellent optical properties. In addition, the J-O intensity parameter and emission cross-section can be obtained. All these results indicate that present potential of Ho3+, Tm3+: NaY 0.1 Gd 0.9 (WO 4) 2 as a solid-state laser material around 2 μm. • Tm3+, Ho3+: NaY 0.1 Gd 0.9 (WO 4) 2 crystals were successfully prepared by Czochralski method. • The crystal shows strong near infrared emission at 2.0 μm with optimal doping concentration. • Concentration quenching in Tm3+, Ho3+: NaY 0.1 Gd 0.9 (WO 4) 2 crystals originates from quadrupole-quadrupole interaction. [ABSTRACT FROM AUTHOR]

Fish live in an aquatic environment rich in various microorganisms and pathogens. Fish mucosal-associated lymphoid tissue (MALT) plays a very important role in immune defence. This study was conducted to characterize the immune response mediated by CcIgZ3 in common carp (Cyprinus carpio.) and investigate the proliferating CcIgZ3+ B lymphocytes in gill. We determined the expression of CcIgZ3 in many different tissues of common carp following stimulation by intraperitoneal injection of TNP-LPS (2,4,6-Trinitrophenyl hapten conjugated to lipopolysaccharide) or TNP-KLH (2,4,6-Trinitrophenyl hapten conjugated to Keyhole Limpet Hemocyanin). Compared with TNP-KLH, TNP-LPS can induce greater CcIgZ3 expression in the head kidney, gill and hindgut, especially in the gill. The results indicate that the gill is one of the main sites involved in the immune response mediated by CcIgZ3. To examine the distribution of CcIgZ3+ B lymphocytes, immunohistochemistry (IHC) experiments were performed using a polyclonal antibody against CcIgZ3. The results indicated that CcIgZ3 was detected in the head kidney, hindgut and gill. To further examine whether CcIgZ3+ B lymphocytes proliferate in the gills, proliferating CcIgZ3+ B cells were analysed by immunofluorescence staining using an anti-CcIgZ3 polyclonal antibody and an anti-PCNA monoclonal antibody. CcIgZ3 and PCNA (Proliferating Cell Nuclear Antigen) double-labelled cells in the gills were located within the epithelial cells of the gill filaments of common carp stimulated with TNP-LPS at 3 dps and 7 dps, and relatively more proliferating CcIgZ3+ B cells appeared in the gills of common carp at 7 dps. These data imply that CcIgZ3+ B cells in the gills might be produced by local proliferation following TNP-LPS stimulation. In summary, compared with those in TNP-KLH, CcIgZ3 preferentially affects the gills of common carp following challenge with TNP-LPS. CcIgZ3+ B cells proliferate in the gills to quickly produce the CcIgZ3 antibody. In addition, CcIgZ3+ B cells can be activated to induce a strong immune response very early locally in the gill and produce the antibody CcIgZ3, which helps exert an immune-protective effect. These results suggest that an effective vaccine can be designed to promote production of the mucosal antibody CcIgZ3. [ABSTRACT FROM AUTHOR]

Fuel blends may be used to meet several operational needs in thermal conversion of biomass waste, including optimization of ash properties and fuel conversion efficiency. In this study, online alkali measurements using surface ionization are employed to study synergistic effects produced by inorganic elements during co-pyrolysis/gasification of wood and straw waste. Synergistic effects on the fuel conversion behavior are not observed during co-pyrolysis, while alkali migration from straw to wood is clearly observed above 600 °C by online alkali monitoring. In contrast, synergistic effects on char conversion and alkali release are substantial during co-gasification. Positive effects on char reactivity during most of the gasification process are attributed to alkali migration from the straw to the wood char, and the most pronounced effect occurs at a gasification temperature of 900 °C and a straw content of 25%. Negative effects on char reactivity are observed at the final gasification stage, which is associated with a significantly reduced alkali release from fuel blends compared to pure wood char. The effect is attributed to the migration of silicon, phosphorus, and aluminum to the wood char, as revealed by scanning electron microscopy with energy dispersive spectroscopy, where the elements react with alkali to form catalytically inactive compounds. The mixing of biofuels is concluded to result in substantial effects on the fuel conversion efficiency, which should be taken into consideration in thermochemical conversion of biomass. [Display omitted] • Online alkali measurements during co-conversion of wood and straw waste. • Wood and straw waste have distinctly different alkali release features. • Alkali release during co-conversion cannot be predicted by simple mixing of the two pure biomass types. • Positive and negative synergies exist at different co-gasification stages. • Silicon migration is observed and causes low alkali release and negative synergy effects. [ABSTRACT FROM AUTHOR]

In this paper, the air dehumidification performance of MIL-101(Cr) and MIL-101(Cr)-SO3H used for solid desiccant air conditioning (SDAC) system is experimental investigated, and compared with conventional desiccant materials including silica gel, molecular sieve and activated carbon. The results show that the moisture saturated adsorption capacity of MIL-101(Cr) is 1206–1392 mg/g at 25.0–33.5 °C/95%RH which is 4–6 times of the conventional adsorbents. MIL-101(Cr) presented an S-shaped isotherm with steep point between 30% and 50%RH which provide the possibility for low temperature regeneration. The water vapor desorption measurement results show that MIL-101(Cr) could have 96.3% (93.5%) desorption rate at 45 °C/15.95%RH (45 °C/30.60%RH) after saturated adsorption at 33.5 °C/58.0%RH. The modified material MIL-101(Cr)-SO3H didn't show better moisture adsorption and desorption performance than MIL-101(Cr) at moderate relative humidity range but higher moisture adsorption capacity at low relative humidity cases. Its saturated adsorption capacity for moisture is 2–3 times of traditional adsorbents. MIL-101(Cr) has shown excellent moisture adsorption capacity and low-temperature regeneration property which makes it be a potential option for SDAC system optimization. [ABSTRACT FROM AUTHOR]

Online alkali measurements using surface ionization are employed to study alkali release during heating of used industrial fluidized bed materials and gasification of biomass-based char and bed material mixtures. The alkali release from the bed materials starts at 820 °C and increases with temperature, the time a bed material has experienced in an industrial process, and in the presence of CO 2. Online alkali measurement during heating of char mixed with used bed material shows significant alkali uptake by the char. Complementary SEM-EDS studies confirm the alkali results and indicate that other important inorganic elements including Si, Mg, and Ca also migrate from the bed material to the char. The migration of elements initially enhances alkali release and char reactivity, but significantly reduces both during the final stage of the gasification. The observed effects on char gasification become more pronounced with increasing amount of bed material and increasing time the material experienced in an industrial process. The ash-layer on the used bed material is concluded to play an important role as a carrier of alkali and other active components. The char and bed material systems are closely connected under operational conditions, and their material exchange has important implications for the thermal conversion. • Online measurements of alkali release performed during heating of used fluidized bed material and gasification of biochar and bed material mixtures. • Bed material that experienced a longer time in an industrial process releases more alkali. • Online alkali measurements detect alkali migration from bed material to char. • Alkali release during char gasification is affected by bed material addition. • The bed material has opposite effects on char reactivity in different gasification stages. [ABSTRACT FROM AUTHOR]

• Alkali release increases remarkably during the final stage of wood char gasification. • Alkali release from straw char decays throughout the gasification process. • Char gasification reactivity is linked with the alkali release behavior. • The dynamic character of alkali contributes to the catalytic effect and the alkali release behavior. Potassium and sodium compounds play both positive and negative roles during biomass gasification, but the detailed behavior of alkali metal compounds remain incompletely understood. In this study, alkali release during CO 2 gasification of biochar is characterized online with a surface ionization method in combination with thermogravimetric analysis of the char samples undergoing gasification. For wood chars, the alkali release rate follows a slowly decreasing trend as the char conversion proceeds, but increases by up to two orders of magnitude when the conversion approaches completion. In contrast, the alkali release from straw char is 40–50 times higher than observed for wood char and decreases continuously during the whole gasification process. A high temperature and a high CO 2 concentration enhance both alkali release and char reactivity. The char preparation method also influences the alkali release from pine char, while the char reactivity is less affected. Alkali release and char reactivity are linked, but other factors including mineral content, surface area and char structure may play important roles for the observed reactivity. The results provide a basis for understanding of alkali behavior during gasification and may help optimize catalytic effects and reduce detrimental issues in biomass gasification. [ABSTRACT FROM AUTHOR]

Chemical-Looping Combustion (CLC) of biofuels is a promising technology for cost-efficient CO 2 separation and can lead to negative CO 2 emissions when combined with carbon capture and storage. A potential challenge in developing CLC technology is the effects of alkali metal-containing compounds released during fuel conversion. This study investigates the interactions between alkali and an oxygen carrier (OC), CaMn 0.775 Ti 0.125 Mg 0.1 O 3-δ , to better understand the fate of alkali in CLC. A laboratory-scale fluidized bed reactor is operated at 800–900 °C in oxidizing, reducing and inert atmospheres to mimic CLC conditions. Alkali is fed to the reactor as aerosol KCl particles, and alkali in the exhaust is measured online with a surface ionization detector. The alkali concentration changes with gas environment, temperature, and alkali loading, and the concentration profile has excellent reproducibility over repeated redox cycles. Alkali-OC interactions are dominated by alkali uptake under most conditions, except for a release during OC reduction. Uptake is significant during stable reducing conditions, and is limited under oxidizing conditions. The total uptake during a redox cycle is favored by a high alkali loading, while the influence of temperature is weak. The implications for the understanding of alkali behavior in CLC and further development are discussed. • KCl aerosol particles are introduced to a fluidized bed of calcium manganite oxygen carrier particles. • Alkali is absorbed by the oxygen carrier under most studied conditions. • Alkali is released when the oxygen carrier is undergoing reduction. • Alkali uptake increases considerably with increasing gas phase alkali concentration. [ABSTRACT FROM AUTHOR]

3D concrete printing technology has been well developed and applied in various engineering fields. Anisotropy is one of the most important properties for the 3D printed cementitious material. Like fiber reinforced composite matters, if the material property is symmetric in only one plane, then the material is called as monoclinic with 13 independent elastic moduli in its constitutive law. In this study, multiscale finite element analysis of the monoclinic 3D printed cementitious material is made. Both material and geometrical randomness and uncertainty are quantified and investigated. At micro scale the material randomness is explored using nanoindentation technique. In addition, the geometrical uncertainty is analyzed through multiscale finite element method at meso scale. Then a stochastic finite element numerical experiment of 3D printed concrete simple supported beam under vertical loading is made based on the 13 independent stochastic elastic constants at macro scale. Computational methods proposed in this paper could be widely applied in 3D concrete printing industry. [ABSTRACT FROM AUTHOR]

Alkali metal-containing compounds are readily released during thermal conversion of solid fuels, and may have both detrimental and beneficial effects on chemical looping combustion. Here, we characterize alkali interactions with the inner walls of a laboratory-scale reactor under oxidizing, reducing and inert conditions at temperatures up to 900 °C. KCl aerosol particles are continuously introduced to the stainless steel reactor and the alkali concentration is measured on-line with a surface ionization detector. Aerosol particles evaporate at temperatures above 500 °C and KCl molecules rapidly diffuse to the reactor wall. Up to 92% of the alkali reaching the wall below 700 °C remains adsorbed, while re-evaporation is important at higher temperatures, where up to 74% remains adsorbed. Transient changes in alkali concentration are observed during repeated redox cycles, which are associated with changes in chemical composition of the wall material. Metal oxides on the reactor wall are partially depleted under reducing conditions, which allow for the formation of a new potassium-rich phase that is stable in a reducing atmosphere, but not under inert conditions. The observed wall effects are concluded to be extensive and include major transient effects depending on gas composition, and the implications for laboratory studies and improved experimental methodology are discussed. [Display omitted] • A flow of KCl aerosol particles is introduced to a laboratory-scale reactor and alkali concentrations are measured on-line. • Interactions between alkali and stainless steel reactor walls are strongly affected by gas environment and temperature. • Alkali-wall interactions need to be considered when studying thermal conversion processes in detail. [ABSTRACT FROM AUTHOR]

Building ventilation is important for occupants' health. There are few studies of associations between home ventilation and occupant's health in China. During 2013‐2016, we measured ventilation in 399 homes in Tianjin and Cangzhou, China, and surveyed the health history of children. Ventilation rates were measured using mass balance of occupant generated CO2. The associations of home ventilation with children's asthma and allergy were analyzed in different strata of time and space. A low bedroom ventilation at night was significantly associated with an increased proportion of rhinitis among children (rhinitis current, adjusted odds ratio (AOR): 1.59; 95% confidence interval (CI): 1.01‐2.49; diagnosed rhinitis, AOR: 3.02 (1.16‐7.89)). Our findings suggest a dose‐response relationship between ventilation rate at night in children's bedrooms and rhinitis current. The night‐time ventilation rate in bedrooms has a greater association with rhinitis than the whole home ventilation rate during daytime. [ABSTRACT FROM AUTHOR]

• Elevated reactivity and alkali release for woody char at the end of gasification. • Lower conversion rate and alkali release for straw char due to inactive silicates. • Alkali release pattern varies for high/low ash char, crucial for gasifier design. In this study time-resolved char conversion and alkali release under steam gasification conditions were investigated using a fixed bed reactor. The behaviour of an industrial char and chars produced from straw and furniture waste was investigated. For woody chars, an increase in gasification reactivity is observed together with a notable alkali release as the gasification approaches completion (degree of conversion > 0.8). In contrast, straw char exhibited a decrease in conversion rate and alkali release throughout the gasification process, attributed to the formation of catalytically inactive potassium silicates inhibiting the catalytic role of alkali. Aerosol particles in the 0.01–22 µm size range are emitted during the char conversion. A fraction is formed by nucleation of alkali compounds and other condensable gases. A wide particle distribution that extends over the whole size range is also observed, and the particles are likely to consist of solid char fragments. The study concludes on the importance of alkali release, illustrating the difference in alkali release pattern for high and low ash char. [ABSTRACT FROM AUTHOR]

[Display omitted] • Online alkali measurement during gasification of wood with fresh bed material mixtures. • The main elements in bed material migrate to the char surface and affect gasification. • Dolomite affects pyrolysis and gasification due to deposition and element migration. • Si-containing materials inhibit gasification and alkali release in the final stage. • Residual Na in sea sand and alumina moves to char surface and catalyzes gasification. Bed materials provide efficient heat transfer and catalytic function in the thermochemical conversion of biomass, but their interactions with the fuel remain incompletely understood. In this study, the effects of bed materials on alkali release and fuel conversion during wood pyrolysis and CO 2 gasification are investigated by online alkali detection combined with thermogravimetric analysis. The investigated bed materials include silica, sea sand, alumina and the natural ores olivine, ilmenite and dolomite. Only dolomite has a significant effect on fuel mass loss and alkali release during wood pyrolysis, while all bed materials influence char reactivity and alkali release during gasification. Sea sand, alumina and dolomite enhance the char gasification during the whole or most of the gasification process, which is related to alkali migration from the bed materials. All bed materials affect char reactivity and alkali release when the conversion approaches completion, and small amounts of some bed materials reduce the alkali release by an order of magnitude. The findings can be understood based on the chemical composition of the different materials. Silicon-rich materials reduce the levels of catalytically active alkali by formation of stable alkali silicates, and a similar explanation applies for ilmenite that captures alkali efficiently. Magnesium and calcium in contrast promote alkali release through their influence on alkali silicate chemistry. Analysis of char surfaces using scanning electron microscopy with energy dispersive spectroscopy indicates that low amounts of several elements are transferred from the bed material to the char where they may be directly involved in the char conversion process. The transferred elements are specific for each bed material and relates to their chemical composition. Mechanisms for material exchange between bed material and char are discussed. [ABSTRACT FROM AUTHOR]

Alkali-containing submicron particles were measured continuously during three months, including late winter and spring seasons in Gothenburg, Sweden. The overall aims were to characterize the ambient concentrations of combustion-related aerosol particles and to address the importance of local emissions and long-range transport for atmospheric concentrations in the urban background environment. K and Na concentrations in the particulate matter PM1 size range were measured by an Alkali aerosol mass spectrometer (Alkali-AMS) and a cluster analysis was conducted. Local meteorological conditions and trace gas and PM concentrations were also obtained for a nearby location. In addition, back trajectory analyses and chemical transport model (CTM) simulations were included for the evaluation. The Alkali-AMS cluster analysis indicated three major clusters: (1) biomass burning origin, (2) mixture of other combustion sources, and (3) marine origin. Low temperatures and low wind speed conditions correlated with high concentrations of K-containing particles, mainly owing to local and regional emissions from residential biomass combustion; transport of air masses from continental Europe also contribute to Cluster 1. The CTM results indicate that open biomass burning in the eastern parts of Europe may have contributed substantially to high PM2.5 concentrations (and to Cluster 1) during an episode in late March. According to the CTM results, the mixed cluster (2) is likely to include particles emitted from different source types and no single geographical source region seems to dominate for this cluster. The back trajectory analysis and meteorological conditions indicated that the marine origin cluster was correlated with westerly winds and high wind speed; this cluster had high concentrations of Na-containing particles, as expected for sea salt particles. [ABSTRACT FROM AUTHOR]

Cuticle is the major transpiration barrier that restricts non-stomatal water loss and is closely associated with plant drought tolerance. Although multiple efforts have been made, it remains controversial what factors shape up the cuticular transpiration barrier. Previously, we found that the cuticle from the tender tea leaf was mainly constituted by very-long-chain-fatty-acids and their derivatives while alicyclic compounds dominate the mature tea leaf cuticle. The presence of two contrasting cuticle within same branch offered a unique system to investigate this question. In this study, tea seedlings were subjected to water deprivation treatment, cuticle structures and wax compositions from the tender leaf and the mature leaf were extensively measured and compared. We found that cuticle wax coverage, thickness, and osmiophilicity were commonly increased from both leaves. New waxes species were specifically induced by drought; the composition of existing waxes was remodeled; the chain length distributions of alkanes, esters, glycols, and terpenoids were altered in complex manners. Drought treatment significantly reduced leaf water loss rates. Wax biosynthesis-related gene expression analysis revealed dynamic expression patterns dependent on leaf maturity and the severity of drought. These data suggested that drought stress-induced structural and compositional cuticular modifications improve cuticle water barrier property. In addition, we demonstrated that cuticle from the tender leaf and the mature leaf were modified through both common and distinct modes. [ABSTRACT FROM AUTHOR]

Emerging evidence indicates that natural killer (NK) cells and NKT-like cells may affect allograft outcomes following solid organ transplantation. However, the roles of these cells in allograft acceptance and dysfunction are controversial. To assess the changes in NK cell and CD3+CD56+ NKT-like cell frequency and phenotype in renal allograft recipients and to explore their associations with acute T-cell-mediated renal allograft rejection (ACR), longitudinal changes in NK and NKT-like cell frequency and phenotype were characterized using flow cytometry and immunohistochemistry in the peripheral blood and kidney allograft tissues in 142 recipients undergoing kidney transplantation. The serum concentrations of NK cell-associated cytokines were also detected by cytokine multiplex immunoassay. In contrast to the healthy controls, recipients with stable graft function exhibited increased proportions of CD56brightCD16dim subsets and decreased proportions of NKT-like cells in their peripheral blood mononuclear cells (PBMCs). Patients with ACR demonstrated increased proportions of NK cells, which were associated with increased CD3−CD56bright subsets and decreased CD3−CD56dim subsets, an increase in the CD56bright/CD56dim ratio in PBMCs and increased CD56+ NK cell infiltration in the kidney allograft, compared with the stable controls. In addition, there was a decreased proportion of NKT-like cells in patients with ACR, and an increased ratio of CD56bright/NKT-like cells compared with the stable controls. These differences appeared to be consistent with the increase in the serum concentrations of C-C motif chemokine 19 and the decrease in the serum concentrations of interleukin-15. These data indicate that CD56bright NK cells may promote the development of ACR, and that NKT-like cells may have immunoregulatory function. The results also imply that the CD56bright/CD56dim ratio may affect the ACR signatures. [ABSTRACT FROM AUTHOR]

Purpose: In the past 60 years, the prevalences of asthma and allergy among children have increased around the world. Neither genetic nor outdoor environmental factors can explain this increase. Methods: We performed a cross-sectional study of 7366 children in Tianjin, China, on associations of home environment and lifestyles with asthma and allergy. Results: The prevalences of diagnosed asthma, rhinitis and eczema among 0- to 8-year-old children in the Tianjin area were 4%, 9% and 39%. Home environment and lifestyle, together with infections, were strong risk factors. For asthma and allergy, the population attributable fraction (PAF) due to modern floors and wall coverings (i.e., laminated wooden floors and painted walls compared to tile floors and lime-coated walls) was 22%. Window condensation in winter and air conditioner use in summer, both of which are proxies for less ventilation, accounted for 7–17% of rhinitis and eczema. Cesarean delivery accounted for 10% of eczema symptoms. We developed a modern life index from appropriate home characteristics and lifestyle and food consumption habits and found it to have a clear dose–response relationship with asthma and allergy in Tianjin children. Conclusions: The results indicate that a "modern" home environment together with a modern lifestyle is associated with increased prevalences of asthma and allergies among children. Appropriate indoor environmental interventions and education of children's caregivers are important in the management of childhood asthma and allergy. [ABSTRACT FROM AUTHOR]

Nuclear factor κ‑light‑chain‑enhancer of B cells (NF‑κB) is one of the most important tumorigenic factors. Although it has been established that NF‑κB is overly activated in human glioma cells, the molecular mechanisms that lead to the signal transduction to NF‑κB and thereby the induction of resistance to apoptosis remain poorly understood. The present study demonstrated that mRNA and protein levels of E3 ubiquitin‑protein ligase 2 (MIB2) were markedly upregulated in glioma cell lines and clinical samples. Immunohistochemical analysis also revealed high levels of MIB2 expression in glioma specimens. Ectopic overexpression of MIB2 was established in glioma cell lines to investigate its fundamental roles in the response of human glioma to apoptotic inducers. The results indicated that ultraviolet irradiation‑induced cell apoptosis was inhibited with MIB2 overexpression in glioma cells. Notably, knockdown of MIB2 using RNA interference was able to increase the sensitivity of glioma cells to the pro‑apoptotic agents. The present study identified that MIB2 induces NF‑κB activation and facilitates the resistance of glioma cell to apoptosis. It was proposed that MIB2 may not only be an important hallmark to glioma disease progression, but that it may also offer novel clinical strategies to overcome resistance to cancer therapies. [ABSTRACT FROM AUTHOR]

This study aims to find out the relationship between pet keeping in childhood and asthma and allergy among children aged 0–8 years old in Tianjin, China. Parental or guardians reports of 7360 children were analyzed. 1490 (21.6%) families kept pets at the time of the survey (current), among them 4.0% cats, and 14.7% dogs. For the first year of life of children (early), 1196 (18.4%) families kept pets, and among them 3.2% cats, and 13.7% dogs. Exposure to a pet in early childhood significantly increased the risk of current wheeze, current dry cough, and diagnosed rhinitis. 17.9% of parents reported an avoidance behavior, i.e., had removed or refrained a pet due to asthma or allergy in the family. After adjustment for avoidance behavior, the negative effect of pet keeping on children’s health became even more obvious, with e.g. an AOR of 3.37 (1.58–7.19) for diagnosed asthma, 3.60 (2.07–6.27) for diagnosed rhinitis, 1.92 (1.31–2.81) for diagnosed eczema. A dose-response relationship between pet keeping at current and current wheeze, current eczema and diagnosed eczema was found. In conclusion, pet exposure in early life of children in Tianjin is a risk factor for asthma and allergies among children aged 0–8 years old. [ABSTRACT FROM AUTHOR]

• Online alkali measurement during gasification of straw and fresh bed material blends. • The main elements in bed material migrate to the char surface and affect gasification. • Dolomite significantly increases alkali release from straw during gasification. • Si-containing materials reduce gasification reactivity and alkali release. • Alumina reduces char gasification reactivity due to K-Al-Si ternary reactions. Alkali-associated problems are key issues for the efficient use of straw that is available as a major renewable energy resource worldwide. The effects of six bed materials commonly used in fluidized bed reactors on straw pyrolysis and char gasification were evaluated using online monitoring of alkali release and thermogravimetric analysis. Scanning electron microscopy with energy dispersive spectroscopy was used to determine the elemental composition of the char surface. In the straw pyrolysis stage, alkali release is reduced by the addition of dolomite and silica due to alkali adsorption on the bed materials, and enhanced by the addition of alumina because of its high sodium content. In the char gasification stage, silica, sea sand, olivine, and ilmenite reduce the char reactivity and alkali release, which is attributed to transfer of Si and Ti from the bed materials to the char and reaction with alkali to form stable and catalytically inactive compounds. Alumina also reduces the char conversion rate by transfer of Al to the char and formation of K-Al-Si and Ca-Al-Si compounds, while alkali release from the straw and alumina blend remains high due to the high Na content in alumina. Dolomite initially appears to increase the char gasification reactivity, but the results are affected by conversion of volatile matter that deposited on the dolomite in the straw pyrolysis stage. Dolomite also significantly increases the alkali release, which is attributed to Ca reactions with aluminosilicate compounds that allow potassium to remain in volatile form. Fresh bed materials are concluded to have significant effects on straw conversion depending on their chemical composition, and the results can contribute to the understanding required for efficient use of straw in commercial applications of biomass thermochemical conversion. [ABSTRACT FROM AUTHOR]

A composite material consisting of nanoscale zerovalent iron particles supported on herb-residue biochar (nZVI/BC) was synthesized and used for treatment of Cr(VI)-contaminated water. The effects of initial pH, chromium concentration, contact time, and competition with coexisting anions and natural organic matter (NOM) were also investigated. nZVI/BC was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy analysis (SEM), and the Brunauer-Emmett-Teller surface area was measured. TEM and X-ray photoelectron spectroscopy (XPS) analysis before and after reaction with Cr(VI) showed that reduction and coprecipitation occurred during hexavalent chromium adsorption. The removal of Cr(VI) was highly pH-dependent and the adsorption kinetics data agreed well with the pseudo-second-order model. The presence of SO 4 2− and humic acid promoted Cr(VI) removal at both low and high concentrations, while the HCO 3 − inhibited the reaction. These results prove that nZVI/BC can be an effective reagent for removal of Cr(VI) from solutions. [ABSTRACT FROM AUTHOR]