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• The effect of HTC on hydrochar properties and Fe migration behavior were studied. • The yield of HHC (60.70%∼69.62%) was much lower than that of WHC (66.77%∼80.91%) • The content of total Fe and Fe3+ of hydrochar decreased with increasing temperature. • Fe could more easily entered the internal pores of the hydrochar. • Fe 3 O 4 peak appeared in HHC and the intensity was enhanced with higher temperature. Iron (Fe) migration mechanisms and hydrochar properties in dyeing sludge hydrothermal carbonization (HTC) are important topics in wastewater treatment. HTC treatment of sludge produces wastewater containing Fe so it is necessary to study the migration behavior of Fe during HTC treatment. This study investigated the basic properties and Fe migration behavior of hydrochar during HTC treatment supplemented with nitric acid (HNO 3). The results showed that the carbonization degree and yield of hydrochar treated with the HNO 3 solution (HHC) were much lower than those of hydrochar treated with ultrapure water (WHC). The variation of total Fe (TF) concentration indicated that the decomposition of organic material and dissolution of minerals in the aqueous release of Fe during the liquid phase, led to much lower TF concentrations compared to the original dyeing sludge. Fe release was further enhanced with the addition of HNO 3 and increase of temperature, rendering a much lower TF concentration of the HHC compared to the WHC. The variations of Fe3+ and Fe2+ concentrations indicated that the HTC-treated hydrochar contained more Fe2+, caused by Fe3+ reduction with hydroxyl methyl-furfural and glucose in the liquid and subsequent Fe2+/Fe3+ transferral to the solid hydrochar phase. X-ray diffraction (XRD) showed that the main Fe content in WHC was FeO(OH), while HHC contained mainly Fe(SO 4)(OH)•2H 2 O and Fe 3 O 4. XPS and XRF showed that Fe could more easily enter the internal pores of the hydrochar instead of being deposited on the surface. This study provided more insights on Fe migration behavior during HTC treatment. [ABSTRACT FROM AUTHOR]

• Fe-loaded hydrochar catalyst was prepared from ferric sludge with one-pot method. • Hydrothermal one-pot method promoted dispersion of active sites on catalyst. • Fe mainly existed in the form of Fe0, Fe 2 O 3 , and Fe 3 O 4 in the catalyst. • Catalyst prepared by one-pot method exhibit superior catalytic efficiency (>70 %) • Amorphous carbon generated from CH 3 was the main source of carbon deposition. Effective treatment of ferric sludge in an eco-friendly method is key to the feasibility of Fenton technology in pollution treatment, contributing to the realization of the "dual-carbon" strategic objectives. In this study, Fe-loaded pyrolyzed-hydrochar catalysts were prepared using simple one-pot hydrothermal carbonization (HTC) method with ferric sludge as the precursor, which greatly reduced the energy and time consumption on the preparation of the sludge derived catalyst. At 800 °C with a reaction time of 20 min, all catalysts showed high toluene removal performance (>60 %) and produced H 2 -rich syngas (H 2 > 90 %). In particular, the catalyst prepared by HNO 3 -assisted HTC (HNC) presented the highest toluene removal efficiency and H 2 yield, 77.52 ± 3.36 % and 11.12 ± 0.66 mol%, respectively. Additionally, the sources of carbon deposits and the interaction between the active site and carbon deposits were analyzed in detail by DFT to reveal the catalytic activity and deactivation mechanism of catalyst. The results showed that the adsorption energy of C generated from methyl on different Fe phases was lowest (the adsorption energy of C was −8.79 eV for Fe, −5.28 eV for Fe 2 O 3 , and −4.70 eV for Fe 3 O 4), suggesting that the adsorption of C on catalyst was the main reason for the formation of carbon deposits. The lowest adsorption energy of the metallic Fe phase for C indicated that Fe0 was coated by carbon deposits during toluene catalytic cracking, which hampered catalytic activity. These results are of great significance for optimizing the preparation of Fe-loaded carbonaceous catalysts and the regulation of Fe active phase. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive numerical modeling approach to analyze and evaluate the performance of a throat biomass updraft fixed bed gasification reactor through computational fluid dynamic simulations. The numerical model uses detailed kinetics to capture the complex thermochemical processes within the gasifier. The influence of key parameters such as reactor design on the gasification efficiency and producer gas composition are systematically investigated. Also, performance metrics, including cold gas efficiency, hydrogen-carbon monoxide ratio, and producer gas heating value, are employed to quantitatively quantify the effectiveness of the throat updraft fixed bed gasification reactor to assess the reactors performance under varying configurations. The hydrogen and carbon monoxide concentrations increased by 6.5 % and 5.2 % by changing the throat diameter ratio from 0.14 to 0.33, respectively. Increased gasification efficiency is also observed, from 65.5 % to 77.84 %, within the same ratio range increase. Similarly, a 2.6 % increase is observed in the lower heating valve between the models with throat-to-diameter ratio of 0.14 and 0.33. The findings contribute to a deeper understanding of the gasification process in throat reactors, offering insights into optimization opportunities for enhanced producer gas quality and overall efficiency. • Gasification of biomass in an updraft gasifier using CFD modeling. • Throat updraft gasifiers have the high tendency of stable gasification temperature. • Gasification temperature improved as the throat ratio is increase. • High throat ratios increase the carbon conversion and cold gas efficiency. • Lower heating value increases as the throat ratio increases. [ABSTRACT FROM AUTHOR]

Current human health risk assessments of soil arsenic (As) contamination rarely consider bioaccessibility (IVBA), which may overestimate the health risks of soil As. The IVBA of As (As-IVBA) may differ among various soil types. This investigation of As-IVBA focused As from geological origin in a typical subtropical soil, lateritic red soil, and its risk control values. The study used the SBRC gastric phase in vitro digestion method and As speciation sequential extraction based upon phosphorus speciation extraction method. Two construction land sites (CH and HD sites) in the Pearl River Delta region were surveyed. The results revealed a high content of residual As (including scorodite, mansfieldite, orpiment, realgar, and aluminum arsenite) in the lateritic red soils at both sites (CH: 84.9%, HD: 91.7%). The content of adsorbed aluminum arsenate (CH: 3.24%, HD: 0.228%), adsorbed ferrum arsenate (CH: 8.55%, HD: 5.01%), and calcium arsenate (CH: 7.33%, HD: 3.01%) were found to be low. The bioaccessible As content was significantly positively correlated with the As content in adsorbed aluminum arsenate, adsorbed ferrum arsenate, and calcium arsenate. A small portion of these sequential extractable As speciation could be absorbed by the human body (CH: 14.9%, HD: 3.16%), posing a certain health risk. Adsorbed aluminum arsenate had the highest IVBA, followed by calcium arsenate, and adsorbed ferrum arsenate had the lowest IVBA. The aforementioned speciation characteristics of As from geological origin in lateritic red soil contributed to its lower IVBA compared to other soils. The oxidation state of As did not significantly affect As-IVBA. Based on As-IVBA, the carcinogenic and non-carcinogenic risks of soil As in the CH and HD sites decreased greatly in human health risk assessment. The results suggest that As-IVBA in lateritic red soil should be considered when assessing human health risks on construction land. [Display omitted] • In lateritic red soil, As from geological origin has low bioaccessibility. • SBET can mainly extract the adsorbed arsenate on Al, Fe and Ca arsenate. • The bioaccessibility of soil As is not related to its oxidation state. • The occurrence of As in Lateritic red soil is dominated by low solubility minerals. • Soil remediation target values can be significantly promoted based on As-IVBA. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cerium vanadate nanorods (CVNRs) with outstanding superoxide dismutase-like activity were designed and constructed. • CVNRs were used as an efficient reactive oxygen species scavenger for treating myocardial ischemia–reperfusion injury (IRI) in hyperhomocysteinemic rat. • CVNRs could effectively protect the microvascular, reduce the myocardial infarction and improve the heart function after IRI. • CVNRs exhibited excellent biocompatibility and biosafety. The combination of homocysteine (Hcy) and copper ion (Cu2+) induces cardiac microvascular ischemia–reperfusion injury (IRI) by causing oxidative stress in the reperfusion treatment of ischemic cardiopathy. Therefore, antioxidant elimination of reactive oxygen species (ROS) shows great potential in the treatment of IRI. Herein, cerium vanadate nanorods (CVNRs) were designed and developed as an efficient ROS scavenger for the treatment of myocardial IRI in hyperhomocysteinemic rat (HHcyR) model. Thanks to its outstanding superoxide dismutase (SOD)-like activity, the CVNRs showed a significant antioxidant effect in human cardiac microvascular endothelial cells treated with Hcy and Cu2+ under hypoxia/reperfusion condition and greatly preserved the morphology and function of mitochondria. Further intravenous administration of CVNRs significantly maintained the integrity and perfusion of microvasculature, minimized the microcirculation malfunction, and finally reduced the myocardial infarction and maintained the heart function after IRI. Moreover, the administration of CVNRs in HHcyR exhibited negligible organ toxicity and inflammation response, indicating their excellent biocompatibility and biosafety. Collectively, the SOD-mimicking CVNRs can serve as a promising antioxidant nanozyme to treat cardiac microvascular IRI complicated with hyperhomocysteinemia, providing a new prospect for the development of antioxidant nanozyme in IRI treatment even with other risk factors. [ABSTRACT FROM AUTHOR]

[Display omitted] • PdNi alloys with surface segregation of Pd@hydrophilic NOC are designed for HER. • Some structures tuned by Pd compositions are key to high HER current density. • A moderate Pd composition is favorable to achieving the optimal structures and HER activity. • Low overpotentials of 240 and 242 mV can drive 1000 and 1590 mA cm−2, respectively. A series of catalysts, which consist of PdNi alloy cores and N, O co-doped carbon (NOC) shells, are developed by pyrolysis of metal–organic framework (PdNi) for hydrogen production with high current densities. The bulk or surface Pd compositions (Pd/(Pd + Ni) molar ratios) of PdNi alloys can be well controlled by the fed ones. Meanwhile, some structural features that are favorable to HER activity, especially to achieving high HER current densities under low overpotentials, are further adjusted by the Pd compositions, including d-band center (ε d) of PdNi alloy affected by surface segregation of Pd, hydrophilicity of NOC shell, and charge transfer and mass diffusion efficiency of an entire catalyst. When the bulk Pd/(Pd + Ni) molar ratio is ∼ 0.21, Pd 0.21 Ni 0.79 @NOC has a moderate ε d , the highest hydrophilicity, the highest charge transfer and mass diffusion efficiency, and finally the highest electric double-layer capacitance (or electrochemical active surface area). Accordingly, it affords the optimal apparent or specific activity for hydrogen production with high current densities under low overpotentials in 0.5 M H 2 SO 4 , including a low apparent η 1000 of ∼ 240 mV or specific η 2500(BET) of ∼ 240.9 mV, and a high current density of ∼ 1590 mA cm−2 at only ∼ 242 mV. [ABSTRACT FROM AUTHOR]

Electrophysiological tests are often used to evaluate hearing loss in infants and young children with conductive hearing loss, no matter to quantify or characterize. However, there are advantages and disadvantages associated with the various electrophysiological tests that are currently available. Therefore, there is no gold standard test. This study aimed to compare the value of narrow-band (NB) CE-Chirp-induced auditory steady-state response (ASSR) and auditory brainstem response (ABR) for assessing hearing thresholds in children with conductive hearing loss. We hope to identify an effective electrophysiological testing method to evaluate conductive hearing loss and provide a reference for clinical hearing assessment of infants with conductive hearing loss. and Methods: We selected 27 children (41 ears) aged 3–6 years with otitis media with effusion (OME). Within 1 day, they underwent behavioral audiometry and NB CE-Chirp-induced ASSR and ABR tests in sequence. Pearson's correlation analysis was performed to compare behavioral audiometry thresholds and ASSR and ABR response thresholds at 500, 1000, 2000, and 4000 Hz. The behavioral audiometry thresholds of all children were strongly correlated with the response thresholds of the two electrophysiological tests, with correlation coefficients of 0.659, 0.605, 0.723, and 0.857 for ASSR, and 0.587, 0.684, 0.753, and 0.802 for ABR. The proportion of children with a difference of ≤10 dB between ASSR and behavioral audiometry thresholds or between ABR and behavioral audiometry thresholds was not high, especially in the low frequencies. ABR results were superior to ASSR results in terms of predicting actual hearing levels. At 0.5, 1, 2, and 4 kHz, the average differences between the behavioral hearing thresholds and ASSR thresholds in the 41 ears were 5.6, 5.7, 2, and 5.6 dB, respectively. The average differences between behavioral hearing thresholds and ABR thresholds was −5.6, −1.4, −6.8, and 3.2 dB, respectively. The hearing loss configuration of the ASSR exhibited a peaked pattern, similar to behavioral audiometry, whereas the ABR exhibited an ascending pattern. The time to perform the single-ear ASSR test was 5.9 min, whereas the ABR test took 17.0 min. ASSR and ABR induced by the NB CE-Chirp correlated well with behavioral audiometry in children with conductive hearing loss. The NB CE-Chirp ASSR has advantages in terms of testing time and hearing configuration evaluation, whereas ABR has better reliability than ASSR. However, the stability of ASSR and ABR induced by the NB CE-Chirp is poor, and the thresholds obtained cannot replace behavioral audiometry in evaluating the true hearing of children with conductive hearing loss. However, ASSR and ABR can be used as auxiliary tests for cross-validation. [ABSTRACT FROM AUTHOR]

• A mass balance-based multi-step model was used to study the reaction kinetics of direct chemical looping process. • The mass balance formulated steps required fewer parameters and thus demanded less computational resource. • The activation energy changes were diversified by adding oxygen carrier. • Oxygen carrier altered the yields and distributions of intermediates and products. The investigation into reaction kinetics provides fundamental insights for reactor design in biomass thermochemical conversion. This work studied the kinetics of biomass chemical looping process based on a multi-step model. Cellulose, xylan, and lignin were employed as biomass representatives. The individual step in the multi-step scheme was formulated with a mass-balance equation form, requiring fewer parameters and thus less computational cost. In addition, the decomposition characteristics of different biomass samples in the presence of oxygen carrier (Fe 2 O 3) were analyzed, and the effects of Fe 2 O 3 on the kinetic parameters of reaction steps were investigated. The results revealed that volatiles pyrolyzed from cellulose and xylan were almost not involved with Fe 2 O 3 reduction at high temperatures (∼1000 K) while playing a major role in terms of lignin (∼1050 K). Moreover, adding OC did not always positively affect the activation energy; in particular, it decreased the activation energy of xylan yet elevated the activation energies of cellulose (at low-temperature zone) and lignin to some extent. [ABSTRACT FROM AUTHOR]

Binary catalyst composed of alkali metal and alkaline earth metal was widely used to overcome the shortcoming of single-metal catalyst. However, the synergistic mechanism between components remains unclear. In present work, sodium and calcium were loaded into the coal char individually or together. TGA gasification was used to investigate catalytic effect. In order to evaluate catalytic mechanism, Raman spectra of gasification residue, Raman spectra of quenched slag and phase composition at thermodynamic equilibrium were obtained. Loading of sodium or calcium significantly increased gasification rate of coal char and catalytic effect of sodium was better than calcium. Above 900 °C, catalytic effect of sodium-calcium binary catalyst was better than that of single catalyst, and gasification residue of binary catalyst loaded char had more calcium silicate and less sodium silicate than gasification residue of single-metal catalyst loaded char. It was speculated that calcium reacted first with silica in coal to inhibit sodium inactivation. Raman spectra of quenched slag and theoretical calculation showed that silica preferentially reacted with calcium oxide to form calcium silicate in calcium oxide-sodium carbonate-silica system, which proved above speculation. Furthermore, the significant catalytic activity of binary catalysts inhibited the graphitization evolution of carbon structure during char gasification, which is conducive to the improvement of gasification rate. [ABSTRACT FROM AUTHOR]

Highlights • Volatiles of pinewood torrefied at 250 °C (PW250) was reduced by only 4% (wt). • Devolatilization and heat transfer performances of PW250 were enhanced. • PW250 contained more cellulose and higher crystallinity degree. • Pyrolysis of pinewood (PW) followed D3 model while PW250 mainly followed D1 model. Abstract Torrefaction is a promising pretreatment technology for biomass thermochemical conversion. In this study, pinewood (PW) and PW250 (torrefied at 250 °C) were prepared for pyrolysis. Torrefaction was carried out in a fixed bed reactor and the pyrolysis was studied by thermogravimetric analyzer using six different heating rates. The results showed that the content of hemicellulose in biomass decreased while cellulose and lignin increased after torrefaction. Moreover, the C-O peaks of torrefied biomass was strengthened in FTIR spectrum and the crystallinity degree was enhanced according to XRD analysis. The performance of devolatilization and heat transfer were improved for PW250 while the volatiles only decreased by only 4%. Activation energy was calculated by three iso-conversion methods. It was found that the PW followed D3 diffusion model, while the PW250 followed D1 diffusion model and tended to higher order reaction model at high conversions. In addition, the thermodynamic parameters were compared. [ABSTRACT FROM AUTHOR]

Abstract Immunochromatographic strip (ICTS) nanosensors are one of the most popular point-of-care (POC) diagnostic devices currently available for rapid target screening. However, the widely used ICTS sensors based on 20–40 nm gold nanoparticles (AuNPs) as labels are limited by their low detection sensitivity due to their relatively weak color intensity. Moreover, the ever-increasing demand for high sensitivity is restricting the application of conventional AuNP-based ICTS methods. Improving the color signal intensity of AuNP nanoprobes can theoretically overcome the limitations encountered by traditional ICTS assays. In recent years, the design of various improved strategies for the enhanced detection sensitivity of ICTSs has received increasing interest. In this review, we systematically summarize the emerging amplification strategies used to enhance the detection sensitivity of conventional AuNP-based ICTS nanosensors. These strategies include 1) signal enhancement mediated by nanoparticle accumulation, 2) signal amplification induced by noble metal nanoparticle growth, 3) signal enhancement based on enzyme-mediated colored product deposition, and 4) signal amplification assisted by nanoparticle flow rate regulation on strips. Representative examples are selected to demonstrate the proof-of-concept and their potential applications in biosensing. The study focuses on elaborating the underlying mechanisms of each strategy for the enhanced colorimetric signal intensity of AuNPs on the test regions of a strip. Finally, we briefly discuss the current limitations and future perspectives in this field. Graphical abstract Image 1 Highlights • Various emerging signal amplification strategies are widely introduced to enable sensitive AuNP-based ICTS nanosensors. • This review provides a systematic overview of emerging amplification strategies for enhanced AuNP-based ICTS nanosensors. • The emphasis is placed on the underlying amplification mechanisms for each strategy. • This work can serve as a reference to promote an extensive and deep research in this field. [ABSTRACT FROM AUTHOR]

Abstract Engaging students in online discussions is challenging. This paper presents a mixed methods study using a gamification approach to promote student engagement in online discussions. A total of 70 students were enrolled in this study from an asynchronous online undergraduate level political science course. The study findings suggested that the gamification approach only had positive effects on the students' number of comments and performance in online discussions who were more aware of the gamification approach. However, it appears that the gamification approach failed in promoting students' sense of community. Additionally, students' responses to the interviews and open-ended questions revealed similar results, although more students in the gamified group indicated that the online discussions forced them to think hard. The limited influence of the gamification approach in the current study may be attributed to several factors that related to the facilitation of the gamification approach, the types of badges, and technical issues. Implications and suggestions for future research have been discussed. Highlights • The gamification approach positively, but limited, influenced student engagement. • Students who were more aware of the gamification approach commented more often. • Students who were more aware of the gamification approach performed better. • The gamification approach failed at promoting students' sense of community. [ABSTRACT FROM AUTHOR]

G231V and F198S mutations in surfactant protein A2 (SP-A2) are associated with familial pulmonary fibrosis. These mutations cause defects in dimer/trimer assembly, trafficking, and secretion, as well as cause mutant protein aggregation. We investigated the effects and mechanisms of chemical chaperones on the cellular and biochemical properties of mutant SP-A2. Chemical chaperones, including 4-phenyl butyric acid (4-PBA), could enhance secretion and decrease intracellular aggregation of mutant SP-A2 in a dose-dependent manner. Interestingly, increased levels of aggregated mutant SP-A2, resulting from MG-132-mediated proteasome inhibition, could also be alleviated by 4-PBA. 4-PBA treatment reduced the degradation of mutant SP-A2 to chymotrypsin digestion in CHO-K1 cells and up-regulated GRP78 (BiP) expression. Overexpression of GRP78 in SP-A2 G231V- or F198S-expressing cells reduced, whereas shRNA-mediated knockdown of GRP78 enhanced aggregation of mutant SP-A2, suggesting that GRP78 regulates aggregation of mutant SP-A2. Together, these data indicate chemical chaperone 4-PBA and upregulation of GRP78 can alleviate aggregation to stabilize and facilitate secretion of mutant SP-A2. The up-regulation expression of GRP78 might partially contribute to the aggregate-alleviating effect of 4-PBA. [ABSTRACT FROM AUTHOR]

• Waste-treated-waste materials for ammonia adsorption. • Cost-effective adsorbents without costly materials or chemicals. • Real-world application with real chicken manure. • Waste-based ammonia adsorbent had 55% capacity of commercial product. • Circular utilization of spent adsorbent for CO 2 capture. NH 3 pollution is a significant problem in the poultry farming because excess NH 3 can negatively impact chicken health and stunt their growth. Therefore, this study investigated the low-cost production of bagasse fly ash (FA)—a byproduct of the sugar industry—as an NH 3 adsorbent. Hydrothermal carbonization and activation were applied to enhance NH 3 adsorption using FA. In the experiments, the adsorption capabilities were improved using industrial waste materials mixed with bamboo char or red mud. The experimental results indicate that bagasse FA mixed with bamboo hydrochar under 10 % loading achieved an NH 3 adsorption capacity of ∼ 1.02 mg-NH 3 /g-adsorbent, or ∼ 55 % of that of the commercial adsorbent. To avoid secondary pollution and provide the spent absorbents with an added value, their use in CO 2 capture applications was evaluated. The results showed that the adsorbent had a 0.28 mmol-CO 2 /g-adsorbent capacity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Steam-release process can improve the dewatering performance of sludge. • Steam-release process was favorable for the formation of porous hydrochar. • The condensate collected during steam-release process was clearer than filtrate. • The mass of sticky wall sample increased from 0.392 g at 160 °C to 2.131 g at 220 °C. • Reducing polar energy of sticky wall sample can improve wall sticking phenomenon. In order to understand hydrothermal carbonization (HTC) process more effectively, the effect of steam-release process at different temperatures (160, 180, 200, and 220 °C) on product properties and wall sticking phenomenon were studied. Experimental results indicated that the approximate equilibrium moisture content (AEMC) of hydrochar obtained with (SRHC) and without (HC) steam-release process were both negatively correlated with zeta potential (R = −0.96326 for HC and R = −0.95825 for SRHC). More importantly, the absolute value of the zeta potential of SRHC was lower than HC indicating steam-release process significantly improve dewatering performance of sludge after HTC treatment. The results of FE-SEM and N 2 adsorption–desorption experiments indicated steam-release process was favorable for the formation of porous hydrochar. The variation of surface functional groups showed that the intensity of all peaks in SRHC was significantly lower than HC, indicating steam-release process which significantly affects surface chemical properties of samples. As for liquid, TOC, TN and COD value of the condensate were lower than filtrate, indicating steam-release process which produces "cleaner" condensed liquid with less organic matter content. The wall sticking phenomenon in the steam-release process became more severe with increasing temperature and the amount of sticky wall sample (SWS) increased from 0.392 g at 160 °C to 2.131 g at 220 °C, which indicated that temperature was key factor affecting the sticking phenomenon on the inside wall of the reactor. The contact angle of SWS and SRHC decreased from 60.083° and 77.283° at 160 °C to 51.317° and 67.967° at 220 °C, and the polar free energy of SWS (12.52–14.00 mN/m) was significantly higher than that of SRHC (1.85–4.53 mN/m), indicating increasing hydrophobicity and reducing polar free energy of sample were key factors in improving sticking phenomenon. [ABSTRACT FROM AUTHOR]

Ultra-small biomass gasification and power generation systems are a promising technology for disaster areas in developed countries and non-electrified rural areas of developing countries. The gasification characteristics of carbonized wood pellets and carbonized wood briquettes without or with 1 wt% sea salt were tested in a pilot-scale updraft fixed-bed gasifier. The results showed that the carbon balance during gasification was easily achieved, and most of the chlorine in the carbonized briquettes with sea salt remained in the residual char and fly ash after gasification. Inorganic chlorine in the solid fuel was transformed into organic chlorine combined with carbon matrix after heat treatment in the gasifier. Syngas with a low heating value higher than 4 MJ·m −3 could be continuously obtained when the system reached a stable condition, which enabled power generation using a gas engine. A combination of several secondary tar removal processes was adopted for the syngas purification. The tar content in the syngas after the gas cleaning for 425 °C-carbonized pellet, 425 °C-carbonized briquette, 475 °C-carbonized briquette, and 475 °C-carbonized briquette with sea salt was 0.98, 0.26, 1.4, and 0.2 g·Nm −3 , respectively. During the stable stage, 425 °C-carbonized pellet showed the highest cold gas efficiency (CGE) of 45.6% and carbon conversion efficiency (CCE) of 57.8%, respectively, with an equivalence ratio (ER) of 0.24. A lower carbonization temperature showed a higher CGE and CCE. The residual char and fly ash after gasification could be considered for reuse as feedstock to further improve the overall process efficiency. The maximum output power was 23 kW at an air flow rate of 40 Nm 3 /h during the gasification of carbonized pellets, and the corresponding overall power generation efficiency of the engine using the syngas was about 27.8%. For 475 °C carbonized briquette, the maximum output power was 18 kW at an air flow rate of 40 Nm 3 /h, and the corresponding overall power generation efficiency of the engine using the syngas was about 25.5%. [ABSTRACT FROM AUTHOR]

Poly(acrylic acid) (PAA) brushes coated onto silica nanoparticles have been widely utilized in bioassays due to their abilities of providing favorable microenvironments and ensuring good biological activities for biomolecules. However, traditional PAA brushes are synthesized by reversible addition–fragmentation chain transfer polymerization. Hence, it is generally difficult to control and characterize the molecular weight of the PAA brushes, which may depress the reproducibility and bring more uncertain results. Herein, atom transfer radical polymerization method is employed to synthesize β -cyclodextrin-cored PAA with uniform and controllable molecular weight. After loading on the surfaces of adamantane-functionalized silica nanoparticles via host-guest interactions, glucose oxidase and probe single strand DNA (ssDNA) are further immobilized on the as-prepared nanoparticles. Meanwhile, capture ssDNA is functionalized on amino modified magnetic beads. In the presence of ssDNA sequence of Hepatitis B Virus (HBV) containing completely matched sequence of both probe and capture ssDNA, a bioconjugate is formed and can be separated by an external magnet. The isolated glucose oxidase can further catalyze glucose into gluconic acid and H 2 O 2 , and then reduce HAuCl 4 on Au seeds. By monitoring the absorption intensity change of the Au NPs at 530 nm, the proposed biosensor with novel signal amplification probes can be used to detect DNA sequence of HBV with high sensitivity and selectivity in both buffer and serum samples. This developed strategy has presented a new way to construct silica nanoparticles coated by PAA brushes for the fields of clinical diagnosis and other life sciences. [ABSTRACT FROM AUTHOR]

This is an exploratory study that examines the influence of the gamification approach on student engagement in online discussions. A gamified online discussion tool, gEchoLu, was implemented in an undergraduate level online course, which held 22 online discussions. The data was collected through gEchoLu database, survey, and individual interviews with 12 students and the teaching assistant. The triangulated results revealed that the gamification approach positively affected student engagement. Factors such as technical issues, classmates' behaviors that either promoted or impeded students from engaging in the gamified online discussions were identified. The interview with the teaching assistant (TA) further revealed the influence of the gamification approach on student engagement from an educator's perspective, and the obstacles that the TA encountered in the gamified online discussions. Lessons learned are also shared in detail. [ABSTRACT FROM AUTHOR]

In this paper, the gasification reactivities of four types of Chinese coal were studied, each with different ash content and coal rank. Of the 4 coal types, 2 were HCl-washed and demineralized to investigate the effects of ash removal (for both dealkalization and demineralization) on coal gasification. The effects of ash on the evolution of physical and chemical structure were further studied using scanning electron microscopy equipped with energy dispersive X-ray analysis (SEM-EDX), N 2 absorption and FT-Raman techniques. The results show that the initial gasification rate of raw chars is twice as high as the HCl-washed and ash-free chars. The gasification rate of ash-free char significantly increases with the increase in carbon conversion and surpasses the gasification rate of raw char when carbon conversion is higher than 50%. Moreover, the specific surface area of ash-free char significantly increases with carbon conversion, resulting in the significant increase in the gasification rate. Whereas the specific surface areas of raw char and HCl-washed char both decrease during high-conversion stages. The FT-Raman analysis shows that the ash-free char band area ratios A D3 /A G and A D4 /A G are lower than those of raw char at the initial gasification stage; this results in the initial gasification rate decrease of ash-free chars. In addition, the ash-free char band area ratio A G /A all is smaller than that of raw char in the high conversion stages. [ABSTRACT FROM AUTHOR]

Compared with the conventional drilling methods, supercritical carbon dioxide used in drilling and completion has considerable potentials and many advantages. However, it is found in the research and practice that there are yet many basic problems to be solved. Wellbore stability is one of them. Firstly, in this paper, on the basis of Span & Wagner equation, combined with unique physical properties of supercritical carbon dioxide, parameters such as temperature and pressure in the wellbore while the supercritical carbon dioxide drilling are calculated. Secondly, the heat and mass transfer effect between the supercritical carbon dioxide and the formation has been studied, and the temperature change near the wellbore formation and stress change near the wellbore have been obtained. Thus, pore pressure change near the wellbore has been obtained. When the depth reaches 1500 m, the downhole temperature will be 12 K lower than the wellbore temperature, and the pore pressure will increase to 20 Mpa as the supercritical carbon dioxide seeps into the formation. Thirdly, mechanical properties change rules when rocks are soaked in the supercritical carbon dioxide are obtained through experiments. The compressive strength decreases by 64%, the elastic modulus increases by 153%, and the poisson ratio decreases by 8%. Based on the above research, the wellbore collapse pressure model has been established. It is revealed that the wellbore collapse pressure rises from 9.17 Mpa to 16.26 MPa with the increase of time, which is still lower than the bottom pressure and cannot lead to instability. Meanwhile, the bottom collapse failure index keeps positive and increases gradually with the increase of time. It means that there is no wellbore enlargement. Therefore, the results have verified the wellbore stability while the supercritical carbon dioxide drilling. It has laid a solid foundation for the future development of supercritical carbon dioxide drilling. [ABSTRACT FROM AUTHOR]

Small-scale, distributed and low cost biomass power generation technologies are highly required in the modern society. The biomass pretreatment process, that is, a combination of carbonization and pelletization processes of cedar wood were explored in this study. For the carbonization process, a novel carbonizer composed of one carbonization chamber and one combustion chamber was tested, and the mass and energy balances during cedar wood carbonization at 400–500 °C were analyzed, respectively. During the initial heating stage, about 22 kg of wood with dry basis should be supplied into the combustion chamber through several batches. When the temperature in the carbonization chamber reached to the range of 200–220 °C, the combustion chamber could be self-heated by burning the pyrolysis gas (tar vapor, CH 4 , H 2 , CO) sent from the carbonization chamber. The specific wood consumption for producing 1 kg of wood char was within 3.6–4.4 kg, which presented an increase trend with increasing the carbonization temperature. Moreover, this carbonization system can deal with different kinds of biomass with various water contents and shapes. For the pelletization process, effects of adding amount of the binder (poval solution), water and the carbonization temperature on the pellet quality were studied so as to explore the optimal condition for making high quality pellets from the crushed wood char. The results indicated that there was an optimal ratio among char, added water, and the binder for making high quality pellets. Considering the energy transfer efficiency and pellet quality, the mass ratio of 0.93:0.32:0.10 for 450 °C-char in the dry basis: added water plus water in char: poval solution was the optimal condition for making high quality pellets. [ABSTRACT FROM AUTHOR]

This article presents two trial studies using the gamification approach in online discussions to increase student engagement. A gamified online discussion tool, gEchoLu, was designed and implemented. The first trial focused on examining student engagement in online discussions. The results indicated that gEchoLu had positive influences on student behavioral engagement, emotional engagement, and cognitive engagement. The second trial aimed to investigate the effect of specific game elements implemented in gEchoLu on student motivation and engagement in online discussions. Findings from the second trial suggested that badges, thumps-ups , progress bars, and avatars in gEchoLu promoted student engagement in online discussions. The limitations and implications are discussed. [ABSTRACT FROM AUTHOR]

Coal gasification fine slag (CGFS) from the entrained-flow coal gasification process mainly contains ash and residual carbon. Currently, the CGFS is normally stacked and landfilled in slag yards, resulting in huge resources waste and potential environmental risks. This study aims to review the research advances of the characterizations, carbon-ash separation and resource utilization of CGFS, so as to reveal the guiding role of CGFS characterizations on the process of separation and resource utilization. In this paper, the characterizations of CGFS are summarized from compositions, structures and dehydration. Methods for separating carbon-ash from CGFS are compared and analyzed. The resource utilization methods of CGFS are reviewed from direct utilization and high-value utilization. Moreover, the future research directions of carbon-ash separation and resource utilization are briefly discussed. Accordingly, this review identifies that particle size is a key factor determining the structure and composition of CGFS. Based on the analysis of the CGFS characterizations, froth flotation shows great application potential for carbon-ash separation from CGFS under the premise of reagent recycling. Blending combustion as the main direction of CGFS resource utilization should be considered. Although the synthesis of porous materials from CGFS is conducive to improving the environmental benefits of coal gasification plants, the optimization research on the preparation methods of CGFS-based porous materials is urgently needed. [Display omitted] • CGFS is a complex mixture composed of inorganic minerals and unburned carbon. • The structure and composition of CGFS are closely related to particle size. • Froth flotation shows great application potential for carbon-ash separation of CGFS. • Blending combustion as the utilization main direction of CGFS should be considered. • Optimization of CGFS-based porous materials preparation methods is urgently needed. [ABSTRACT FROM AUTHOR]

• Heat treatment can easily lead to Maillard reaction. • The structure and molecular weight of melanoidins are related to substrate, temperature, pH and other factors. • The characteristics and common characterization methods of melanoidins are studied. • High doses of melanoidins show obvious inhibitory effect on anaerobic fermentation. Melanoidins are Maillard products produced in the thermal pretreatment of organic solid waste represented by food waste and sludge. Their effect on anaerobic fermentation is related to energy recovery efficiency. Based on the researches of melanoidins in food field, this review paper aims to improve the understanding of melanoidins in waste treatment and anaerobic fermentation. The formation mechanism of melanoidins is complex, and the molecular weight and structure are not systematic and standardized. During the Maillard reaction process, the basic characteristics of melanoidins are affected by the type of reactants, temperature, pH and the presence of metal ions. In addition, the physicochemical and biological properties of melanoidin itself involve the mechanism explanation of melanoid behavior. Antioxidant, antimicrobial and metal chelating abilities are related to the inhibition or promotion of melanoidins in anaerobic fermentation, but the specific mechanism (such as cytotoxicity or the effect on interspecific electron transfer) still needs to be further explored. Finally, the characterization of melanoidins can provide more accurate semi-quantitative information with the development of analytical technology. The colorimetric method, ultraviolet/visible (UV/Vis) spectrophotometry, excitation-emission matrix joint region integration method and parallel factor analysis method developed from the color and structure characteristics of melanoidins have become the commonly used characterization techniques. In this review, the formation mechanism and influencing factors of melanoidins from organic solid waste by thermal pretreatment were investigated, the characteristics and characterization techniques of melanoidins were reviewed, and the possible ways of melanoidins affecting high quality products were put forward, which provided a reference for the efficient utilization of organic solid waste by thermal pretreatment coupled with anaerobic fermentation. [ABSTRACT FROM AUTHOR]

• Heat treatment can easily lead to Maillard reaction. • The structure and molecular weight of melanoidins are related to substrate, temperature, pH and other factors. • The characteristics and common characterization methods of melanoidins are studied. • High doses of melanoidins show obvious inhibitory effect on anaerobic fermentation. Melanoidins are Maillard products produced in the thermal pretreatment of organic solid waste represented by food waste and sludge. Their effect on anaerobic fermentation is related to energy recovery efficiency. Based on the researches of melanoidins in food field, this review paper aims to improve the understanding of melanoidins in waste treatment and anaerobic fermentation. The formation mechanism of melanoidins is complex, and the molecular weight and structure are not systematic and standardized. During the Maillard reaction process, the basic characteristics of melanoidins are affected by the type of reactants, temperature, pH and the presence of metal ions. In addition, the physicochemical and biological properties of melanoidin itself involve the mechanism explanation of melanoid behavior. Antioxidant, antimicrobial and metal chelating abilities are related to the inhibition or promotion of melanoidins in anaerobic fermentation, but the specific mechanism (such as cytotoxicity or the effect on interspecific electron transfer) still needs to be further explored. Finally, the characterization of melanoidins can provide more accurate semi-quantitative information with the development of analytical technology. The colorimetric method, ultraviolet/visible (UV/Vis) spectrophotometry, excitation-emission matrix joint region integration method and parallel factor analysis method developed from the color and structure characteristics of melanoidins have become the commonly used characterization techniques. In this review, the formation mechanism and influencing factors of melanoidins from organic solid waste by thermal pretreatment were investigated, the characteristics and characterization techniques of melanoidins were reviewed, and the possible ways of melanoidins affecting high quality products were put forward, which provided a reference for the efficient utilization of organic solid waste by thermal pretreatment coupled with anaerobic fermentation. [ABSTRACT FROM AUTHOR]

To close the loop for the circular economy (CE) transition in the construction industry, forward logistics (FL) and reverse logistics (RL), as enabling operations for CE, are important topics to be addressed. However, current research mainly focuses on either FL or RL, with a lack of synthesis that presents an overview of the bi-directional logistics system integrating FL and RL and related mechanisms to close the loop. This review, therefore, explores the current cases of FL and RL in the construction arena through a systematic literature review (SLR) process. A review framework to synthesize and compare both FL and RL operations in various phases of the construction project life cycle (CPLC) has been established for this purpose. The phases include - in FL: design, manufacturing, construction, and operations; and in RL: deconstruction, product reuse, waste distribution, and material reprocessing. The review concludes that while similar methods and CE strategies are used in FL and RL, RL operations require more integration between supply chain actors to close the loop for CE in construction. The findings also indicate that more lateral integration between FL and RL phases beyond the life cycle and industrial boundaries is necessary for CE-driven construction projects, instead of only direct vertical integration with up- and down-stream partners. This review proposes a new conceptual framework of circular logistics integration (CLI) that consists of channel creation, network integration, and inventory management to guide and inspire future research in tackling the systematic barriers that hinder materials and resource flow from RL to FL in construction life cycles. • An analytical framework is developed to understand forward and reverse logistics activities in building life cycles. • Logistic activities are analyzed using case studies to provide operational insights. • The results show that logistics operations in the circular life cycle are interrelated and could potentially be integrated. • Circular logistics integration is proposed, aiming to improve the management of channels, networks, and inventories. • Logistics may play a key role in circular construction to connect inventories of deconstruction to new distribution channels. [ABSTRACT FROM AUTHOR]

Respiratory diseases mainly include asthma, influenza, pneumonia, chronic obstructive pulmonary disease, pulmonary hypertension, lung fibrosis, and lung cancer. Given their high prevalence and poor prognosis, the prevention and treatment of respiratory diseases are increasingly essential. In particular, the development for the novel strategies of drug treatment has been a hot topic in the research field. Ginsenosides are the major component of Panax ginseng C. A. Meyer (ginseng), a food homology and well-known medicinal herb. In this review, we summarize the current therapeutic effects and molecular mechanisms of ginsenosides in respiratory diseases. The reviewed studies were retrieved via a thorough analysis of numerous articles using electronic search tools including Sci-Finder, ScienceDirect, PubMed, and Web of Science. The following keywords were used for the online search: ginsenosides, asthma, influenza, pneumonia, chronic obstructive pulmonary disease (COPD), pulmonary hypertension (PH), lung fibrosis, lung cancer, and clinical trials. We summarized the findings and the conclusions from 176 manuscripts on ginsenosides, including research articles and reviews. Ginsenosides Rb1, Rg1, Rg3, Rh2, and CK, which are the most commonly reported ginsenosides for treating of respiratory diseases, and other ginsenosides such as Rh1, Rk1, Rg5, Rd and Re, all primarily reduce pneumonia, fibrosis, and inhibit tumor progression by targeting NF-κB, TGF-β/Smad, PI3K/AKT/mTOR, and JNK pathways, thereby ameliorating respiratory diseases. This review provides novel ideas and important aspects for the future research of ginsenosides for treating respiratory diseases. [Display omitted] • 176 papers were reviewed for ginsenosides in the treatment of respiratory diseases. • Ginsenosides Rb1, Rg1, Rg3, Rh2, and CK are commonly for treating respiratory diseases. • The NF-κB, TGF-β/Smad, PI3K/AKT/mTOR, and JNK pathways are molecular mechanisms. [ABSTRACT FROM AUTHOR]

In this work, a heating stage microscope and a thermogravimetric analyzer were adopted to explore behaviors of char-slag/ash transition during CO 2 gasification of rice straw (RS) and Neimeng lignite (NM). Effects of demineralized treatment and various gasification temperatures on the char-slag/ash evolution process were studied. Both RS and NM particles exhibited shrinkage particle form at a moderate reaction temperature (1000 °C). The variation of the existential state of K with char-slag/ash transition could well explain the reactivity differences between RS raw char and demineralized char. Compared to RS raw char, NM raw char showed a more significant flow of molten slag at 1350 °C, which accounted for the high inhibitory effects at the late stage of NM raw char gasification. There is a threshold conversion (x = 0.9) during the evolution processes of NM char samples to NM slag/ash at 1200 °C and 1350 °C, while this threshold value is only existing at 1000 °C for RS char gasification. [ABSTRACT FROM AUTHOR]

Apelin, a small bioactive peptide, plays an important role in the pathogenesis of mood disorders through the endogenous ligand APJ. Although the anxiolytic effect of apelin is well established, the mechanisms are poorly understood. In this study, we hypothesized that apelin played an anxiolytic role in chronic normobaric hypoxia (CNH)-induced anxiety like behavior in mice, which might be associated with an inhibition of nuclear factor-κB (NF-κB) activation in the hippocampus. To this end, mice were exposed in a normobaric hypoxic chamber with a fraction of inspired oxygen (FIO 2 , ∼10%, 23 h/d) with or without apelin-13 application (20 nmol kg −1 d −1 , i.p .), for 4 weeks. The anxiety-like behavior was tested by elevated plus maze and open field. Activities of NF-κB, microglial, and related signaling pathways in the hippocampus during this pathological process were examined. We found that CNH treatment decreased APJ but increased Iba-1 proteins expression, as well as nucleus translocation of p50 and p65 in the hippocampus, which were reversed by apelin-13 treatment. In addition, apelin-13 treatment ameliorated CNH-induced anxiety-like behavior in mice, suggesting anxiogenic effect of apelin-13 might be mediated by an inhibition of NF-κB activation in microglial of the hippocampus. Furthermore, apelin-13 treatment reversed p-CAMKII decrease in the hippocampus under CNH treatment. Apelin-13 treatment did not affect anxiety-like behavior and relative proteins expression in normoxia control mice. Finally, we found that rats with CNH treatment decreased APJ expression while enhanced NF-κB activation in the hippocampus, providing additional evidences that NF-κB activation in hippocampus in CNH-induced anxiety-like behavior in rats we reported previously might be associated with an inhibition of APJ activity. In conclusion, the present results illustrated that inhibition of APJ and promotion of NF-κB activation in the microglial of hippocampus might be involved in anxiogenic effect in CNH-exposed mice, and apelin-13 ameliorates CNH-induced anxiety-like behavior might be associated with an inhibition of NF-κB activation. [ABSTRACT FROM AUTHOR]

The effects of water on the pyrolysis and gasification characteristics of coal water slurry (CWS) and pulverized coals with different ranks have been studied in the present work. Rapid pyrolysis characteristics (i.e. char yield, char structure evolution) of raw carbonaceous materials with varied water contents were investigated by using a high frequency furnace at 800–1200 °C. Moreover, gasification characteristics of the pyrolysis char were studied by using a thermogravimetric analyzer (TGA). The results indicate that at the pyrolysis temperature of 800 °C, the char yield of Wu-ran-cha-bu (WRCB) lignite slightly decreased with increasing the water content from 2.1 wt.% to 13.98 wt.%, while that of Yun-nan (YN) lignite showed a more significant decrease with increasing water content from 2.2 wt.% to 11.54 wt.%. This could be attributed to a higher coal reactivity of YN lignite than that of WRCB lignite. When the pyrolysis temperature was at or above 1000 °C, due to more significant in-situ coal-steam interactions, a lower char yield of both the pulverized lignites were observed with increasing water content from 2 wt.% to above 10 wt.%. CWS char presented a higher graphitization degree than pulverized coal char. The carbon microcrystalline structure factors (i.e. L 002 /d 002 value) of pyrolysis char increased with coal rank, which might reflect the variation trend of the graphitization degree from low rank coal to high rank coal. During the rapid heat treatment processes, the water evaporation and the in-situ steam-char gasification were favorable for void formation for both pulverized coals with high water contents and CWS. Notably, during the gasification processes of three different rank coals at 1200 °C, a more significant inhibition effect of residual ash on CWS char was observed compared to the pulverized parent coal char with high carbon conversion (x > 0.9). [ABSTRACT FROM AUTHOR]

• The micro-particle effect of hydrothermal pretreatment on matrix was verified. • Low temperature hydrothermal pretreatment was more conducive to methane generation. • Hydrothermal pretreatment coupled anaerobic fermentation could achieve zero waste discharge. Anaerobic fermentation is one of the ways to realize the recycling, harmlessness and reduction of food waste. The potential of methane production via anaerobic fermentation was analyzed by the model compounds of food waste after hydrothermal pretreatment, and the micro-particle effect of hydrothermal pretreatment on matrix was verified by the change of physicochemical properties and morphology characteristics of model compounds of food waste in hydrothermal group, and the influence of hydrothermal pretreatment on anaerobic fermentation methane production was explored. From the perspective of particle size, the hydrothermal groups had good decomposition characteristics. With the increase of hydrothermal temperature, the surface morphology changed from smooth to rough, and the specific surface area increased from 0.29 m2·g−1 in the control group to 2.82 m2·g−1 in the hydrothermal group at 200 °C. In addition, the model compounds of food waste were anaerobic fermented under the condition of constant temperature water bath (55 °C). The results showed that the methane yield of 140 °C hydrothermal group was the highest (0.368 NL·g−1 VS), which increased by 27.78% compared with the control group, and the methane generation performance of the fermentation process was improved. Through material balance and energy analysis, it is revealed that hydrothermal pretreatment coupled anaerobic fermentation could achieve zero waste discharge and partial energy recovery. [ABSTRACT FROM AUTHOR]

Based on percolation theory, the discrete model of char particle gasification with structure evolution under various distinct regimes was developed. Initial structure of individual char particle was modeled as a simple cubic lattice consisting of a large number of small sites. Sites arranged in the char lattice were randomly classified as either carbon, ash, or macropore, depending upon the proximate analysis data and the porosity of coal char. Suggested model was used to study the effects of structure parameter and reaction condition on the gasification reactivity and the evolution of char structure. Simulation results showed that under external diffusion controlled regime, the gasification rate decreased as reaction advanced for char particles with lower porosity (porosity < 0.15), and the gasification rate vs. conversion curves exhibited maxima for large char particles with higher porosity (porosity > 0.15). Besides, the particle sizes of coal char decreased slowly in the early stage of gasification, and then they decreased slightly fast. The gasification reaction of fine coal chars under the external diffusion controlled region could inhibit the particle fragmentation and reduce the formation of fine ash particles to a certain degree. [ABSTRACT FROM AUTHOR]

Rapid pyrolysis characteristics of three different rank coals and two petroleum cokes were investigated using a drop tube furnace. Moreover, gasification characteristics of char samples were studied in an in-situ heating stage. The results showed that H 2 and CO were the main gaseous pyrolysis products of coal samples. The relative content of H 2 and CO increased with increasing pyrolysis temperature. The volume fraction of H 2 in syngas increased with increasing coal rank, whereas that of CO showed the contrary trend. Anthracite and petroleum cokes (Petcoke 1 and Petcoke 2) exhibited a great similarity in gas release characteristics. There was a maximum value for the specific surface area and graphitization degree of char samples with increasing pyrolysis temperature. The results of in-situ heating stage experiments indicated that the most of char particles reacted with CO 2 in the shrinking particle mode at the initial stage. Char samples of petcokes and anthracite were similar in slow consumption of particle skeleton during gasification. Interestingly, petcokes demonstrated particle migration, residual agglomeration, and rapid consumption at the later reaction stage. The variation trend of the area shrinkage ratio of char samples was well verified by the TGA results. [ABSTRACT FROM AUTHOR]

• RSM- BBD was adopted to study the combined effects of HTC parameters of corn straw. • Higher temperatures declined hydrochar yield and increased high heating value of hydrochar. • Improved coalification degree shows higher potential and stability of hydrochar as a solid fuel. • Synergy effect during co-gasification was stronger than that of during co-pyrolysis. In this study, hydrothermal carbonization was adopted as a promising approach for the improved management and better use of agro waste. The response surface methodology- Box Behnken design (RSM-BBD) approach was applied to investigate the individual and interactive effects of operating parameters (temperature, particle size and residence time) on hydrochar properties. From the results, carbon mainly retained in solid fraction, while oxygen content in hydrochar decreased from 48.83 % to 23.32 % as the temperature increased from 180 °C to 240 °C. In addition, O/C and H/C were also decreased from 0.8 to 0.2 and 1.8 to 1, specifying higher degree of coalification. The maximum hydrochar yield, energy yield and higher heating value of the hydrochar were 67.46 %, 77.64% and 19.71 MJ kg−1, respectively. The response surface of process parameters and their combine effects showed that, the decline of hydrochar and energy yield was due to the increase of temperature (>200 °C) and residence time. Particle size showed mild effect over the range studied. From ANOVA test, temperature was found the most significant parameter, followed by particle size and residence time, respectively. By comparing the experimental and calculated rate values, the synergy effect of co-gasification of hydrochar and coal was much more significant than that of co-pyrolysis. However, the co-gasification synergy decreased as the addition of severe HTC hydrochar in blends. The application of RSB-BBD for diagnosis of HTC parameters for hydrochar production seems to be an appropriate step for technological scalability. [ABSTRACT FROM AUTHOR]

• Effects of pyrolysis temperature, residence time and atmosphere were investigated. • Release of AAEMs was associated with char structure evolution in rapid pyrolysis. • CO 2 promoted Na release in early stage and Ca and Mg release in late stage. The release law of alkali and alkaline earth metals (AAEMs) during coal pyrolysis is crucial for controlling scaling, corrosion and slagging in the utilization of high AAEMs coal. To approximate entrained-flow bed gasification process, a free-falling reactor was used for coal pyrolysis to study the release characteristics of AAEMs in nascent char. Effects of pyrolysis temperature, residence time and atmosphere were investigated. The cumulative release of Na, Ca and Mg at 1100 °C was 68.0%, 47.5% and 69.8%, respectively. As pyrolysis temperature increased from 900 °C to 1100 °C, the release of Na, Ca and Mg increased by 7.0 %, 3.5% and 5.3%, respectively. The cumulative release of AAEMs increased with the pyrolysis residence time, but the release rate decreased significantly in middle and late stages. The promoted thermal decomposition of functional groups by CO 2 resulted in a lower char yield. CO 2 promoted Na release in early stage and Ca and Mg release in late stage. Furthermore, release of AAEMs was associated with char structure evolution in rapid pyrolysis. The presence of CO 2 , high temperature and prolonged residence time led to enhanced particle fragmentation, increased surface cracks, and intensified thermal decomposition of functional groups, resulting in the migration of AAEMs in carbon matrix to char surface and the release of AAEMs organically bound to carbon matrix. [ABSTRACT FROM AUTHOR]

Immunoassay has shown great potential in the detection of various disease protein biomarkers because of its high specificity. However, the sensitivity of conventional immunoassay is relatively limited due to its insufficient colorimetric signal transduction. Herein, we report a novel dynamic light scattering (DLS) immunosensing strategy for ultrasensitive detection of protein markers based on the covalent organic framework-gold nanoparticle (COF@AuNP) heterostructures combined with the gold growth. By taking advantage of the unique acid response characteristics of imine-linked COF, the COF@AuNP is designed as a signal amplifier to boost the release of AuNPs, and then the released AuNPs are enlarged by gold growth to amplify the DLS signal transduction and thus remarkably improve the sensitivity. Combined with the double antibody sandwich magnetic immunoassay, the COF@AuNP-amplified DLS immunosensor successfully achieve the highly sensitive quantitative detection of N-terminal brain-type natriuretic peptide. The limit of detection reaches up to 14 fg mL−1 with the total assay time less than 2 h. The linear detection range was from 0.32 to 1000 pg mL−1, and the coefficient of variation was below 12.5%. Briefly, this immunosensor is demonstrated with high selectivity, accuracy, reproducibility, and reliability in spiked and actual whole blood samples. The COF@AuNP-amplified DLS immunosensing strategy holds high promise as an alternative for detecting disease biomarkers. [Display omitted] • COF@AuNP heterostructures were synthesized as a signal-amplification light-scattering probe. • The obtained imine-linked COF@AuNP exhibited unique acid response property. • A novel COF@AuNP amplified-DLS immunosensor was developed for ultrasensitive detection of NT-proBNP with an LOD of 14 fg mL−1. • Selectivity, accuracy, reproducibility, and reliability of this method were well characterized. [ABSTRACT FROM AUTHOR]

The q -deformation of the infinite-dimensional n -algebras is investigated. Based on the structure of the q -deformed Virasoro–Witt algebra, we derive a nontrivial q -deformed Virasoro–Witt n -algebra which is nothing but a sh- n -Lie algebra. Furthermore in terms of the pseud-differential operators, we construct the (co)sine n -algebra and the q -deformed S Diff ( T 2 ) n -algebra. We find that they are the sh- n -Lie algebras for the n even case. In terms of the magnetic translation operators, an explicit physical realization of the (co)sine n -algebra is given. [ABSTRACT FROM AUTHOR]

Background Circulating microRNAs (miRNAs) have attracted interests as non-invasive biomarkers of physiological and pathological conditions, which may be applied in noise-induced hearing loss (NIHL). However, no epidemiology studies have yet examined the potential effects of NIHL or noise exposure on miRNA expression profiles. Objectives We sought to identify permanent NIHL-related miRNAs and to predict the biological functions of the putative genes encoding the indicated miRNAs. Methods In the discovery stage, we used a microarray assay to detect the miRNA expression profiles between pooled plasma samples from 10 noise-exposed individuals with normal hearing and 10 NIHL patients. In addition, we conducted a preliminary validation of six candidate miRNAs in the same 20 workers. Subsequently, three miRNAs were selected for expanded validation in 23 non-exposed individuals with normal hearing and 46 noise-exposed textile workers which including 23 noise-exposed workers with normal hearing and 23 NIHL patients. Moreover, we predicted the biological functions of the putative target genes using a Gene Ontology (GO) function enrichment analysis. Results In the discovery stage, compared with the noise exposures with normal hearing, 73 miRNAs demonstrated at least a 1.5-fold differential expression in the NIHL patients. In the preliminary validation, compared with the noise exposures, the plasma levels of miR-16-5p, miR-24-3p, miR-185-5p and miR-451a were all upregulated ( P < 0.001) in the NIHL patients. In the expanded validation stage, compared with the non-exposures, the plasma levels of miR-24, miR-185-5p and miR-451a were all significantly downregulated ( P < 0.001) in the exposures. And compared with the noise exposures, the plasma levels of miR-185-5p and miR-451a were slightly elevated ( P < 0.001) in the NIHL patients, which were consistent with the results of preliminary validation and microarray analysis. Conclusion The two indicated plasma miRNAs may be biomarkers of indicating responses to noise exposure. However, further studies are necessary to prove the causal association between miRNAs changes and noise exposure, and to determine whether these two miRNAs are clear biomarkers to noise exposure. [ABSTRACT FROM AUTHOR]

Pyrolysis behaviors of two lignite coals with different drying conditions were determined by a thermogravimetric analyzer coupled with mass spectrometer (TG-MS) and a high-frequency furnace. An in-situ heating stage microscope was adopted to observe the morphological changes during char-CO 2 gasification process. It is concluded that the effects of moisture contents in coals on the gaseous release process during coal pyrolysis mainly depend on coal type, final pyrolysis temperature and heating method. The in-situ heating stage experiments indicate that the shrinking particle mode is suitable to illustrate the gasification reaction mechanism in the initial and midterm reaction stages of all the lignite char samples. Although drying conditions have significant effects on coal pyrolysis process under rapid heating, these dewatering conditions result in little noticeable reactivity loss of the char during the subsequent char-CO 2 gasification reaction. The measuring results of catalytic active sites can well explain the similar reactivity of lignite coals with different drying conditions. [ABSTRACT FROM AUTHOR]

Pyrolysis and catalytic pyrolysis behaviors of two kinds of coals with different ranks were determined by thermogravimetric analyzer–mass spectrometry (TG–MS) and a high-frequency furnace. A quantitative method of on-line gas analysis was proposed using quadrupole mass spectrometry. The effects of pyrolysis temperature (650–800 °C) and Na 2 CO 3 loading amount (0–15 wt.%) on the gaseous compounds evolution were investigated. The results show that loading Na 2 CO 3 on coal was favorable for gas production in pyrolysis process. The yields of light gas species in the high-frequency furnace were lower than those in TG–MS. By comparing the pyrolysis yields of gas and solid in the high-frequency furnace and TG–MS, it was concluded that heating methods had great effects on the reaction mechanism and product distribution of pyrolysis and catalytic pyrolysis of coals. Moreover, the evolution processes of gaseous compounds were related to the presence of different functional groups in the solid samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effects of HTC on coconut shell fuel properties were quantitatively studied. • The composition of hydrochar is similar in condition of 200 °C–0 h and 180 °C–3 h. • The migration behavior of different forms potassium was studied after HTC process. • Kinetic models were adopted to predict products yield during HTC. Hydrothermal carbonization is a promising renewable technology to produce high quality solid biofuel with characters of sterilization, micronization, and homogeneous. In this work, coconut shell was used as feedstock to investigate the products distribution, reaction kinetics and the migration of potassium during HTC process. Experiments were carried out in 180–240 °C with residence time of 0–5 h. The results showed that the content of fixed carbon increased from 20.76 wt% to 49.80 wt%, and HHV increased from 20.75 MJ/kg to 31.77 MJ/kg at 240 °C with the holding time of 3 h. The ratio of H/C dropped from 1.78 to 0.86 and O/C dropped from 0.68 to 0.16 which all indicated the improvement of fuel performance. The effects of increasing temperature and prolonging residence time on the products were in the same direction but different in severity. The properties of the products changed little after the residence time was more than 1 h. In addition, chemical fractionation method was used to investigate migration behavior of potassium. The best removal temperature of potassium was 200 °C which decreased potassium concentration from 2.7 mg/g to 0.6 mg/g specifically. Due to the increase of specific surface and porosity caused by high temperature, the content of potassium rose slightly at 220 and 240 °C. A kinetic model was adopted to predict the products distribution and yield of solid phase and gas phase. The activation energies (Ea) of different reaction paths were calculated and the results showed that Ea of gas formation is greater than that of solid. Migration behavior of potassium and modeling of HTC process is of great significance for design, optimization of industrial HTC reactor and selecting the best time for discharging and feeding to achieve better performance. [ABSTRACT FROM AUTHOR]

Catalytic pyrolysis and gasification characteristics of coal using Na 2 CO 3 as a catalyst were studied in a high-frequency furnace and thermogravimetric analyzers (TGA), respectively. Interactions of Na 2 CO 3 with carbon at both pyrolysis and gasification phases were observed by in-situ heating stage microscope. The effects of pyrolysis temperature (650–800 °C) and catalyst loading amount (0–15 wt.%) on the associated pyrolysis and gasification processes were investigated. The results show that, H 2 and CO are the main pyrolysis gas products and the yields of these two gas increase with the increasing of Na 2 CO 3 in the range of 0–15 wt.%. The in-situ heating stage experiments indicated that one main gasification reaction form was observed for Shenfu char samples. Most of SF char particles reacted with CO 2 in the form of shrinking core mode without cracking, and certain particles presented fragmentation phenomenon in the reaction process. There is an optimal loading amount of Na 2 CO 3 for the best catalytic gasification effect of Shenfu bituminous char, while Na 2 CO 3 does not reach the saturation amount for the catalytic gasification of Zunyi anthracite coal. The activation energy of catalytic Shenfu coal gasification with 10 wt.% Na 2 CO 3 is 31.5 kJ mol − 1 less than that of non-catalytic coal gasification, which indicates that Na 2 CO 3 can improve the kinetics of coal gasification with CO 2 . [ABSTRACT FROM AUTHOR]

[Display omitted] • ZIF-8 and BSA were elaborately designed as a ratiometric sensor for doxycycline. • The sensor coupled the fluorescence signal and the second-order scattering signal. • The sensor possessed rapid response, superior sensitivity and excellent selectivity. • The sensor was applied to the analysis of doxycycline in basa fish and pure milk. The residue problem of tetracycline antibiotics, especially doxycycline (DC), in animal foodstuffs has attracted much attention. This paper reported ZIF-8 and bovine serum albumin (BSA) as a ratiometric fluorescence-scattering sensor for DC. The mechanism relied on the disassembly of ZIF-8 caused by DC, bringing weakened second-order scattering, and the double fluorescence amplification of DC under ZIF-8 with BSA, inducing enhanced fluorescence. The response of the sensor was completed within 1 min, and the detection limit for DC (3.4 nM) was 1–2 orders of magnitude lower than the reported ones. The distinguishment of DC from other tetracycline antibiotics was also achieved by the sensor. The sensor was applied to detecting DC in animal foodstuffs with satisfactory recoveries (80.0–104.0%). Hence, this work develops a rapid, sensitive and selective ratiometric sensor to monitor the DC residue in animal foodstuffs, also opens the window to construct ratiometric DC sensors with the fluorescence-scattering strategy. [ABSTRACT FROM AUTHOR]

Highlights: [•] Signal amplification strategy based on Fc incorporated PS was proposed. [•] PS-Fc prevented the leakage of Fc and greatly amplified the immunosensor signal. [•] A detection limit of 1pgmL−1 was obtained for PSA detection. [•] Results of PSA detection in serum samples were satisfactory. [ABSTRACT FROM AUTHOR]

• A practical thermoelectric leg is proposed and realized. • The procedure of fabrication at lab level and a method for mass production are presented. • Optimal current improvement is demonstrated by the analysis as well as the experimental test. The maximum temperature difference, which is corresponding to the optimal current, is important for evaluating the performance of thermoelectric coolers (TECs). As a representative of the thermoelectric leg with non-constant cross-section, the pyramidal thermoelectric leg has more advantages than the traditional cuboidal thermoelectric leg due to the large temperature gradient. However, the fabrication is much complex. In this work, a new shaped thermoelectric leg for TECs with almost the same property with the pyramidal legs is proposed and a simple practical approach for fabrication by taking one-side cut from the cuboidal leg is presented. Optimal current improvement is demonstrated by the theoretical calculation and the finite element simulation as well as the test results. [ABSTRACT FROM AUTHOR]

Abstract: Sensitive electrochemical immunosensor for the detection of platelet-derived growth factor BB (PDGF-BB) based on metal nanoparticles mediated electron transfer was reported. The immunosensor was prepared on insulating self-assembled monolayer (SAM) modified gold electrode using gold nanoparticles (AuNPs) as electrochemical label. The attachment of AuNPs onto the electrode through the formation of the sandwich immuno-complex altered the insulating properties of the electrode, and in return mediates electron transfer between electrode and a redox indicator, , resulting in redox current. The redox current was further enhanced with the deposition of silver nanoparticles onto electrode using AuNPs acts as nuclei. Under optimized experimental conditions, the redox current is dependent on the amount of metallic silver deposited onto the electrode surface, which in return is proportional to the concentration of PDGF-BB detected. The immunosensor has high sensitivity, selectivity and wide linear range (0.005–10ng/mL). This immunosensor preparation method may find wide applications for the detection of other proteins. [Copyright &y& Elsevier]

Abstract: -axis epitaxial Srm−3Bi4TimO3m+3 (SBTi, and 6) thin films were fabricated on conductive LaNiO3 (LNO) coated LaAlO3 (LAO) substrates by pulsed laser deposition. The structure was characterized by x-ray diffraction (including , rocking curve, and scans) and atomic force microscopy. The epitaxial relationship was established (001)SBTi//(001)LNO//(001)LAO, [100]SBTi//[110]LNO//[110]LAO when orthorhombic structure indexing was used for SBTi. It is revealed that the films with odd have a ferroelectric hysteresis loops whereas those with even have collinear polarization-electric field curves. The microstructure background responsible for the observations was discussed. Our results provide further evidence that the -axis polarization of Bi-layered oxides depends on the parity of . [Copyright &y& Elsevier]

Abstract: Composite multiferroics usually show larger magnetoelectric effect, which is important for actual application, than their single-phase counterparts. Here, (1−x)BiFeO3–xCoFe2O4 and (1−x)Bi0.8La0.2FeO3–xCoFe2O4 (, 0.2, and 0.3) multiferroic composite ceramics were prepared. The former system shows low resistivity, which prevents the intrinsic ferroelectric measurements, whereas for the later system, the composition with shows well saturated polarization–electric field hysteresis loop at room temperature, the measured remnant polarization is 13.4 μC/cm2. However, for the compositions with and 0.3, the measured loops show negative curvature near saturation, which is attributed to the decreased resistivity. Further magnetic measurements reveal that at low temperature, 0.9Bi0.8La0.2FeO3−0.1CoFe2O4 shows ferromagnetic nature whereas at high temperature antiferroelectric-like nature, which is discussed based on comparing its magnetic response with that of pure Bi0.8La0.2FeO3 and CoFe2O4 ceramics. These results may be helpful for further understanding, and designing, new multiferroic composites. [Copyright &y& Elsevier]

Multispectral pedestrian detection is a difficult task, especially with pedestrian images of different sizes. In most convolutional neural network (CNN) models, the shared receptive fields of each layer are of the same size, which constrains detection results of multiple scales pedestrians. In this paper, we propose a dynamic selection scheme to adaptive adjust receptive field size in multispectral pedestrian detection. Specifically, a network in network (NIN) is employed to combine visible and thermal information. Selective kernel networks (SKNets) which uses selective kernel unit with different kernel size are employed. To effectively fuse the feature representation in each layer, a build block is designed, in which different features are fused. Feature pyramid is employed to integrate feature information in each layer. We empirically show that our method outperforms existing 8 state-of-the-art methods on one multispectral dataset and 4 state-of-the-art methods on another multispectral dataset. Detailed analyses show that our proposed method can capture multispectral pedestrian detection of different scales, which confirms the effective of SKNets for adaptively resizing the receptive field sizes. In addition, our method can operate at 14 frames per second (fps) on a GPU. [ABSTRACT FROM AUTHOR]

Fluorescent probes with in-situ visual feature have received numerous attentions for detecting doxycycline (DC), a semisynthetic tetracycline antibiotic widely used in animal husbandry. However, reported fluorescent probes commonly fail to selectively detect DC among tetracycline antibiotics due to their structural similarity. In this work, bovine serum albumin-capped gold nanoclusters (BSA-AuNCs) were ingeniously used as the ratiometric fluorescent probe for detecting DC over other tetracycline antibiotics through the selective sensitization effect of BSA on DC. After adding DC, the red fluorescence of BSA-AuNCs almost remained unchanged, while the green fluorescence of DC also emerged under the sensitization of BSA. BSA-AuNCs showed the highest response toward DC among tetracycline antibiotics ascribed to the strongest sensitization effect of BSA on DC. BSA-AuNCs also displayed the features of simple synthesis, short response time (1 min) and low detection limit (36 nM). BSA-AuNCs were finally applied to detecting DC in fish samples, and further fabricated into test strips for ease of carrying. Thus, this work proposes an efficient strategy to design fluorescent probe for selectively detecting DC among tetracycline antibiotics. [Display omitted] • BSA-AuNCs could selectively detect doxycycline (DC) among tetracycline antibiotics. • The selective fluorescence sensitization effect of BSA on DC caused this phenomenon. • Fluorescent test strips were further fabricated using BSA-AuNCs for ease of carrying. [ABSTRACT FROM AUTHOR]