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Sealing performance between two contacting surfaces is of significant importance to stable operation of proton exchange membrane (PEM) fuel cells. In this work, an analytical micro-scale approach is first established to predict the gas leakage in fuel cells. Gas pressure and uneven pressure distribution at the interface are also included in the model. At first, the micro tortuous leakage path at the interface is constructed by introducing contact modelling and fractal porous structure theory. In order to obtain the leakage at the entire surface, contact pressure distribution is predicted based on bonded elastic layer model. The gas leakage through the discontinuous interface can be obtained with consideration of convection and diffusion. Then, experiments are conducted to validate the numerical model, and good agreement is obtained between them. Finally, influences of surface topology, gasket compression and gasket width on leakage are studied based on the model. The results show that gas leakage would be greatly amplified when the asperity standard deviation of surface roughness exceeds 1.0 μm. Gaskets with larger width and smaller thickness are beneficial to sealing performance. The model is helpful to understand the gas leakage behavior at the interface and guide the gasket design of fuel cells. [Display omitted] • An analytical model is built to predict gas leakage rate in fuel cells. • Uneven pressure distribution at the interface is considered in the model. • Leakage is amplified when asperity height standard deviation exceeds 1.0 μm. • Leakage becomes serious when gasket compression ratio is lower than 8%. • Gaskets with larger width and smaller thickness are beneficial to sealing. [ABSTRACT FROM AUTHOR]

Many-objective optimization problems (MaOPs) are challenging tasks involving optimizing many conflicting objectives simultaneously. Decomposition-based many-objective evolutionary algorithms have effectively maintained a balance between convergence and diversity in recent years. However, these algorithms face challenges in accurately approximating the complex geometric structure of irregular Pareto fronts (PFs). In this paper, an information entropy-driven evolutionary algorithm based on reinforcement learning (RL-RVEA) for many-objective optimization with irregular Pareto fronts is proposed. The proposed algorithm leverages reinforcement learning to guide the evolution process by interacting with the environment to learn the shape and features of PF, which adaptively adjusts the distribution of reference vectors to cover the PFs structure effectively. Moreover, an information entropy-driven adaptive scalarization approach is designed in this paper to reflect the diversity of nondominated solutions, which facilitates the algorithm to balance multiple competing objectives adaptively and select solutions efficiently while maintaining individual diversity. To verify the effectiveness of the proposed algorithm, the RL-RVEA compared with seven state-of-the-art algorithms on the DTLZ, MaF, and WFG test suites and four real-world MaOPs. The results of the experiments demonstrate that the suggested algorithm provides a novel and practical method for addressing MaOPs with irregular PFs. • A novel RL-RVEA addresses many-objective optimization with irregular pareto fronts. • A reinforcement learning-based adaptive reference vector to guide the direction of convergence. • A scalarization approach preserves the diversity of solutions for next generation. • The RL-RVEA outperforms seven advanced many-objective optimization algorithms. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Sn(II)/Sn(IV)-doped CeZrO x catalysts were prepared by co-precipitation method. • Diethylamine combustion over CeZrSnO x -(Sn2+) had high activity and N 2 selectivity. • CeZrSnO x -(Sn2+) showed high hydrothermal stability during diethylamine combustion. • The ratio of Sn2+/Sn4+ had a significant impact on the catalytic activity. • The strong acidic sites on the catalyst were conducive to diethylamine combustion. The synthesis of CeZrSnO x by co-precipitation with different valence-state of Sn for diethylamine combustion is novel and intriguing. In this research, the Sn(II)/Sn(IV)-doped CeZrO x catalysts (CeZr(Sn)O x -(Sn2+) and CeZr(Sn)O x -(Sn4+)) were facilely prepared using the co-precipitation method, and their catalytic activities on destruction of diethylamine were evaluated. Detailed characterizations of the catalysts were conducted using X-ray photoelectron spectrometer (XPS), X-ray powder diffraction (XRD), hydrogen-temperature programmed reduction (H 2 -TPR), temperature programmed ammonia desorption (NH 3 -TPD) and so on. For diethylamine combustion, CeZr(Sn)O x -(Sn2+) showed higher activity and nitrogen selectivity than other catalysts, and a high conversion of diethylamine (>90 %) at 250 °C was obtained. After hydrothermal aging treatment, a high conversion (>90 %) and high N 2 selectivity maintained over CeZr(Sn)O x -(Sn2+)-H at 280 °C, indicating high hydrothermal stability of CeZr(Sn)O x -Sn2+. Owe to the large specific surface area (SSA), high oxygen mobility and strong redox performance, and the synergy between metal elements in CeZr(Sn)O x -Sn2+ catalysts, the catalytic properties were enhanced. Moreover, Sn2+/Sn4+ ratio in the catalyst and strong acidic sites on the surface of the catalyst both had significant impacts on the catalytic activity and N 2 selectivity of the catalyst. Finally, the mechanism of diethylamine combustion over CeZr(Sn)O x -Sn2+ was obtained by analyzing the reaction through in-situ diffuse reflection infrared Fourier-transform spectrum (in situ DRIFTS) test. [ABSTRACT FROM AUTHOR]

[Display omitted] [ABSTRACT FROM AUTHOR]

Strontium (Sr) ions were added to porous magnesium (Mg) oxide with silicon and fluorine by microarc oxidation (MAO) to improve its osteogenic and pro-angiogenic properties. First, pure Mg was oxidized by MAO, and Sr was added by electrolysis. The surface of the resulting Sr coating was characterized by SEM, EDS, and EDS mapping. The release of Sr ions was monitored by ICP-OES. The antibacterial property of the coating was assessed against Staphylococcus aureus. The effect of Sr coating on osteogenesis was tested in MC3T3-E1 cell line by performing cell adhesion and proliferation tests, alkaline phosphatase (ALP) activity detection, cell morphology characterization, alizarin red staining, and osteogenic-related gene expression analysis. Finally, HUVECs cells were used to test the effect of Sr coating on angiogenesis through cell migration and tube formation assays, VEGF quantification, chicken embryo chorioallantoic membranes (CAM) test, and angiogenic-related gene expression analysis. The results showed that Sr coating had a hierarchical microstructure with a microporous structure evenly covered with nano-grains and that the Sr elements from the coating were released slowly and continuously. Sr coating had effective antibacterial properties and promoted cell adhesion, proliferation, ALP release, calcium nodule formation, and upregulated osteogenic gene expression. Moreover, the coating could promote migration, tube formation, VEGF expression, and angiogenic gene upregulation in endothelial cells. Sr coating also enhanced angiogenesis of CAM. This study supports that Sr coating on Mg- MAO enhances osteogenesis and angiogenesis. [ABSTRACT FROM AUTHOR]

In aim to study the influence of circulating ash used as heat carrier and dolomite used as catalyst on mercury transition during the step conversion of coal pyrolysis and combustion, five experiments with different operating conditions were conducted in this study, including four pyrolysis experiments of raw coal, coal/ash, coal/dolomite, coal and ash/dolomite, and combustion experiment of pyrolysis solid product. By changing the experimental conditions including final pyrolysis temperature, heating rate, coal-ash ratio and dolomite type, the transition path and final mercury distribution in the step conversion process were comprehensively analyzed. Experiments results indicated that mercury completely released out from coal when the final pyrolysis temperature was 600 °C. The individual addition of ash could promote the mercury release from coal at lower temperature. Dolomite could catalyze the oxidation of Hg0 in gas phase, and the modified dolomite had better catalytic capacity for Hg0 oxidation than natural dolomite. The addition of circulating ash and natural dolomite both had a certain catalytic effect on Hg0 emission peaks during the coal pyrolysis. Increasing the coal-ash ratio was conducive to the oxidation of Hg0 in pyrolysis gas. During the direct combustion of coal, the content of Hg0 released into the gas phase could reach to 69.97%. By adding ash, ash/natural dolomite and ash/modified dolomite to the coal pyrolysis process, the content of Hg0 in pyrolysis gas decreased to 58.99%, 34.77% and 31.30%, respectively. The research is able to offer the theoretical foundation for mercury contaminants' removal and process optimization of the step conversion technology. • Ash heat carrier can promote the release of mercury in coal at lower temperatures. • Fe 2 O 3 has the strongest catalysis ability towards Hg0. • Dolomite and circulating ash have a synergistic effect on Hg0 oxidation. • The step conversion process greatly reduces the treatment pressure of mercury. [ABSTRACT FROM AUTHOR]

Reliable sealing is necessary for the stable operation of proton exchange membrane fuel cell (PEMFC). In practical application, various materials have been tried in PEMFC sealing. However, the mechanical properties of these sealing materials, which play a key role in the sealing stability, have not been fully understood in PEMFC environment, especially after long-term operation. In this paper, according to the operating environment of PEMFC, sealing material experiments are carried out to explore the differences in mechanical behaviors of sealing materials, including silicone rubber (SR), fluororubber (FR), nitrile rubber (NBR) and ethylene-propylene-diene-terpolymer rubber (EPDM) and the variation of mechanical properties of these sealing materials is predicted as time goes on. The results indicate that compression rate has a great influence on sealing contact stress. SR and EPDM, with the variation of 0.15 MPa and 0.45 MPa in stress, show the best and worst mechanical stability at different compression rates, respectively. In terms of temperature, it is found that SR can adapt to different operating temperature of PEMFC and only 18% variation is found from 20 °C to 100 °C. Finally, based on Time-Temperature Superposition (TTS), high temperature experiments are conducted to predict long-term relaxation stress under PEMFC working condition. The analysis results are beneficial for choosing suitable sealing material, and it can also be applied to predict sealing ability in PEMFC. • Mechanical behavior differences of different sealing materials were compared. • Influences of compression rate and temperature on stress were discussed. • The better gasket material was selected for proton exchange membrane fuel cell. • High temperature experiments were conducted to predict long-term stress relaxation. [ABSTRACT FROM AUTHOR]

This review summarizes the recent findings of the roles of bombesin receptor subtype-3 (BRS-3) in various patho-physiological conditions. Studies have demonstrated that two mammalians bombesin-like peptides, GRP and NMB, exhibit a large range of functions by binding to three receptors. Knockout studies showed that the mice BRS-3 has important effects on tumor growth, energy homeostasis, glucose regulation, satiety, and lung development (1,7). BRS-3 is an orphan receptor whose natural ligand is unknown. However, several agonists and antagonists have been synthesized which facilitate its characterization, (D-Tyr6, β-Ala11, Phe13, Nle14) Bn-(6-14) and MK-5046 are agonists, whereas ML-18 and Bantag-1 are antagonists. With the development of several selective, high-affinity BRS-3 agonists and antagonists, recent studies provided some insights into the biological effects of BRS-3 in several disease states including lung cancer, obesity, diabetes mellitus, asthma, and kidney diseases. [ABSTRACT FROM AUTHOR]

Loess deposits as a unique terrestrial archive of paleo-dust contribute to understanding the wide-scale and long-term dust transport from source to sink. This study provided diagnostic constraints on the sources of clay-sized particles in the Chinese Loess Plateau (CLP) loess by expanding the potential dust source areas with the Kyzylkum Desert and the Central Asian loess. Based on the grain sizes and the particle-size-specific trace elements, we characterized the major provenance and the sedimentary process of the Kyzylkum Desert sands. The results indicate the main derivation of Kyzylkum Desert sands from the Tian Shan-derived sediments, with limited large-scale mixing. The desert was thought to be a sink region, instead of an important dust source, which was supported by its weak genetic links to the Central Asian loess. With integration of the published data set about trace element and Sr Nd isotopic composition and our results, combined with the simulation results, we revealed that the Badain Jaran and Tengger deserts in northwestern CLP, rather than the Taklimakan and Kyzylkum deserts further west, played an important role in supply of the clay-sized particles for the CLP loess. The findings implied that the fine particles were primarily related to the East Asian winter monsoon, instead of the high-level westerly airstreams. In this context, we attributed the asynchronous timing of enhanced dust accumulation during the last glacial maximum (LGM) over Greenland and North Pacific (early LGM) and on the CLP (late LGM) to the differences in the major dust sources and in the atmospheric circulation systems. • Kyzylkum Desert makes negligible contribution to the Central Asian loess. • Origin of clay-sized components in the CLP loess is systematically characterized. • The findings of this study help to improve understanding of the Asian dust cycle. [ABSTRACT FROM AUTHOR]

Abstract The energy consumed during the desalination process in a flow-electrode capacitive deionization (FCDI) is recovered by a two-chamber device, where the adsorbed electrodes are discharged with constant current. When single constant discharge current is applied, the maximum energy of 36.3 J can be obtained with 0.50 mA/cm2 discharge current density. Much more energy is recovered by applying successive discharge currents. With additional conductive agent carbon nanotubes in the suspend carbon electrodes, the ratio was further enhanced by 60%. Increased salt concentration of the electrolyte could decrease the energy consumption and improve the energy recovery. The energy recovery ratio was promoted to 9.4% when the salt concentration of the electrolyte increased to 9.60 g L−1. Highlights • Two-chamber device to recover the energy from FCDI. • Successive discharging currents benefit the energy recovery. • Additional CNT improved energy recovery ratio by 60%. • Increased salt concentration of electrode improved energy recovery performance. [ABSTRACT FROM AUTHOR]

Highlights • An architectural assumption management process with guidelines is developed. • Two case studies were conducted to validate the process. • The process can help to make architectural assumptions explicit. • The process can help to identify and reduce invalid architectural assumptions. Abstract Context Architectural assumption management is critical to the success of software development projects. In this paper, we propose an Architectural Assumption Management (AAM) process, comprised of four AAM activities: Architectural Assumption Making, Description, Evaluation, and Maintenance. Objective Evaluating the AAM process in architectural assumption management, regarding the ease of understanding and the effort of conducting the AAM process, as well as the effectiveness of using the AAM process to make architectural assumptions explicit and to identify and reduce invalid architectural assumptions. Method An explanatory study with 88 first-year master students in software engineering, and an exploratory study with five practitioners from five companies. Results (1) the ease of understanding the AAM process is moderate for first-year master students but easy for practitioners; (2) the effort of conducting the AAM process is moderate for first-year master students; (3) Making and Evaluation took the students more time than Description and Maintenance; (4) the practitioners considered Evaluation as the most time consuming activity; (5) the AAM process can help to make architectural assumptions explicit and to identify and reduce invalid architectural assumptions in projects. The majority of the students and practitioners agreed that Architectural Assumption Evaluation is the most helpful activity for all these three aspects. For other activities, there are different opinions about their helpfulness; and (6) there are various factors identified that can impact the aforementioned results. Being aware of and properly adjusting these factors can facilitate the application of the AAM process in projects. Conclusions The AAM process aims at systematically managing architectural assumptions in software development. The results of the case studies provide preliminary empirical evidence for the evaluation of the AAM process. [ABSTRACT FROM AUTHOR]

Highlights • Complexation of Hg with the antibiotics resulting in the dissolution of Hg compounds from the sediment. • Hg ions in the sediment can also promote the degradation of antibiotics. • The degradation of TC/OTC radicals generates CH3+ groups which can react with Hg° to form MeHg. Abstract The role of antibiotics commonly used in fish culture activities in methylmercury (MeHg) formation in mariculture sediments (MS) and in reference sediments (RS) was studied using simulation microcosms. MS and RS were split into three equal batches. Two batches were spiked with Hg(NO 3) 2 aqueous solution at levels of 2 and 8 mg kg−1 (dry weight basis) and the remainder served as a control batch. Tetracycline (TC) and oxytetracycline (OTC) (2.5 g and 10 g of each) were added to each treatment. Sediment THg concentration decreased during the culture period possibly due to complexation of Hg with the antibiotics resulting in the dissolution of Hg compounds from the sediment. More importantly, the MeHg concentration increased after 32 days together with a decrease in the concentrations of the antibiotics in the sediment. The complexation of TC or OTC with Hg resulted in the transport of electrons from TC or OTC to Hg2+ due to the high electronegativity of Hg2+. Subsequently, Hg2+ was reduced to Hg° which reacted with CH 3 + derived from TC or OTC. The use of antibiotics may therefore promote the formation of MeHg in sediments. [ABSTRACT FROM AUTHOR]

This study constructed a 1000 L modularized MFC system, the largest volume so far, to treat practical municipal wastewater. This MFC system was operated under two different water flow connections in two municipal wastewater treatment plants (MWTP) for more than one year to test their treating abilities for wastewater with both low (average 80 mg L −1 ) and high initial COD concentration (average 250 mg L −1 ). The COD concentration in the effluent from the MFC system remained below 50 mg L −1 with a removal rate of 70–90%, which stably met the level A of the first class in discharge standard of pollutants for MWTP of China. A maximum power density of 125 W m −3 (7.58 W m −2 ) was generated when the MFC system was fed with artificial wastewater, while it lay in a range of 7–60 W m −3 (0.42–3.64 W m −2 ) when treating municipal wastewater. The energy recovery of 0.033 ± 0.005 kWh per m 3 of municipal wastewater was achieved, with a hydraulic retention time (HRT) of 2 h. [ABSTRACT FROM AUTHOR]

This study offers an efficient method to improve manufacturing technique of metallic bipolar plates (BPPs) so as to simultaneously reduce contact resistance (CR) and maximize power density in proton exchange membrane fuel cell (PEMFC). CR plays an important role in the energy conversion in the cell and can be normally reduced by coating on the BPP surface. Nevertheless, the effect of fabrication process on the CR has not been revealed, especially for the welding and forming characteristics. In this paper, a comprehensive three-dimensional finite element model of BPP/gas diffusion layer (GDL) assembly was established to investigate the influences of coating, weld and dimensional error on the CR, which are produced during the fabrication process of metallic BPPs. Experiments were carried out to validate the accuracy of the model. The results indicate that direction and distribution of the current in the cell change significantly with altering the weld path of metallic BPPs, which are different from graphite BPPs. 47% CR reduction is observed for the case of dense weld arrangement. For the coating process, it is found that the necessity of coating on both sides of single BPP is quite low if channel number is less than 20. Statistic simulation was conducted to investigate the effect of dimensional error on CR. Specially, 14.5% increment in CR is found when the dimensional error exceeds 30 μm. The methodology developed is beneficial to the fabrication management of metallic BPPs and the efficiency improvement of PEMFC. [ABSTRACT FROM AUTHOR]

To realize the high value-added utilization of low-rank coal and elucidate the selectivity of solvent structure and oxygen-containing compounds in low-rank coal, Zhaotong (ZT) lignite and Naomaohu (NMH) sub-bitumite were subjected to thermal dissolution in three types of oxygen-containing solvents with different properties, namely ethanol (ET), tetrahydrofuran (THF) and ethyl acetate (EA). The soluble portions (SPs) obtained were separated by column chromatography into three types of fractions: hydrocarbon (HY), non-hydrocarbon (NHY) and asphaltene (ASP). The results indicated that the yields of SPs in all three solvents for each coal was ET > THF > EA, and the ratios of column chromatographic fractions of SPs of the two coals were significantly different, with lower asphaltene content in the SPs of NMH. The thermal dissolution process of the three solvents significantly reduced the oxygen content of low-rank coal, and the deoxygenation capacity was in the order of ET > THF > EA. More medium or low polarity compounds could be obtained from NMH than from ZT through thermal dissolution process. ET showed excellent selectivity for the generation of both phenols and esters, where the phenols were mainly alkylphenols. THF could release highly condensed polycyclic compounds from coal thus more naphthalenols containing substituent groups were detected in phenols. And it was more selective to COO bonds in NMH than ZT from the results of XPS. More esters were detected in the SPs of NMH compared with ZT. EA had a strong selectivity for C O in low-rank coals, and the thermal dissolution process released a large number of esters, which could be divided into alkanoates and aromatic acid esters. This study can provide a theoretical basis for extracting high value-added chemicals from low-rank coal under mild conditions. [Display omitted] • Thermal dissolution can obtain oxygenated chemicals and upgrading coals. • Ethanol has the strongest deoxygenation capacity. • Ethyl acetate shows selective dissociation ability for esters. • Tetrahydrofuran dissociates highly condensed polycyclic compound such as naphthols. [ABSTRACT FROM AUTHOR]

This study employed an open external circuit, rather than a closed circuit applied in previous studies, to operate an microbial fuel cell (MFC) sensor for real-time nitrate monitoring, and achieved surprisingly greater sensitivity (4.42 ± 0.3–6.66 ± 0.4 mV/(mg/L)) when the nitrate was at a concentration of 10–40 mg/L, compared to that of the MFC sensor with a closed circuit (0.8 ± 0.05–1.6 ± 0.1 mV/(mg/L)). The MFC sensor operated in open circuit (O-MFC sensor) delivered much more stable performance than that operated in closed circuit (C-MFC sensor) when affected by organic matter (NaAc). The sensitivity of O-MFC sensor was twice that of C-MFC sensor at a low background concentration of organic matter. When organic matter reached a high concentration, the sensitivity of O-MFC sensor remained at an acceptable level, while that of C-MFC sensor dropped to almost zero. Challenged by a combined shock of organic matter and nitrate, O-MFC sensor delivered evident electrical signals for nitrate warning, while C-MFC failed. Another novel feature of this study lies in a new mathematical model to examine the bioanode process of nitrate monitoring. It revealed that lower capacitance of the bioanode in O-MFC was the major contributor to the improved sensitivity of the device. [ABSTRACT FROM AUTHOR]

Toxicity monitoring is essential for the protection of public health and ecological safety. Microbial fuel cell (MFC) sensors demonstrated good potential in toxicity monitoring, but current MFC sensors can only be used for anaerobic water monitoring. In this study, a novel gas diffusion (GD)-biocathode sensing element was fabricated using a simple method. The GD-biocathode MFC sensor can directly be used for formaldehyde detection (from 0.0005% to 0.005%) in both aerobic and anaerobic water bodies. Electrochemical analysis indicated that the response by the sensor was caused by the toxic inhibition to the microbial activity for the oxygen reduction reaction (ORR). This study for the first time demonstrated that the GD-biocathode MFC sensor has a detection limit of 20 ppm for formaldehyde and can be used to monitor air pollution. Selective sensitivity to formaldehyde was not achieved as the result of using a mixed-culture, which confirms that it can serve as a generic biosensor for monitoring gaseous pollutants. This study expands the realm of knowledge for MFC sensor applications. [ABSTRACT FROM AUTHOR]

La 3 + and mixed-rare earth magnetic chitosan beads (MCLB and MCLRB) were successfully prepared for fluoride removal, respectively. The adsorbents were characterized by scanning electron microscope and magnetic response. Batch experiments were carried out to investigate the adsorbent performance based on the influence of various factors such as adsorbent dosage, contact time, initial solution pH and co-existing anions on the fluoride adsorption. Results showed that MCLB and MCLRB followed the pseudo-second-order kinetic model with the correlation coefficient value of 0.9925 and 0.9985 respectively. The adsorption process was mainly chemical adsorption. The isotherm data was well fitted both Langmuir model and Freundlich model. The adsorption capacity of the adsorbents were 20.53 and 22.35 mg/g respectively. The optimum pH value for fluoride ion removal was 5.0. The effects of co-existing anions on the fluoride sorption followed the decreasing order of CO 3 2 – > HCO 3 – > SO 4 2 − > NO 3 − > Cl − . Fluoride adsorption on MCLB and MCLRB could be attributed to ion exchange between fluoride and OH groups with the Fe O coordinate bond promotion. Our study revealed that MCLB and MCLRB performed strong adsorption capacity for fluoride ion. In particularly, MCLRB could be a more cost-effective adsorbent to remove fluoride from aqueous solution. [ABSTRACT FROM AUTHOR]

Inefficient extracellular electron transfer within bioanode leads to low current production by microbial fuel cell (MFC). In this study, magnetite was sprinkled in electroactive biofilm with the aid of magnet field. Magnetite located inside biofilm (interior-doped biofilm) facilitated the electron delivery of electroactive bacteria far away from electrode surface. Electron transfer efficiency was improved by 12% and 37% compared with that of biofilms with magnetite located at the interface of biofilm/electrode (surface-doped biofilm) and that without any magnetite (control biofilm) respectively. The output power density of MFC with interior-doped biofilm (764 ± 32 mW m −2 ) was greatly increased compared with that of MFCs with surface-doped biofilm (604 ± 22 mW m −2 ) and control biofilm (475 ± 12 mW m −2 ). SEM images showed that magnetite evenly distributed inside the interior-doped biofilm and penetrated the electroactive biofilm, which would facilitate extracellular electron transfer across electroactive biofilms and thus improving the bioelectricity production. [ABSTRACT FROM AUTHOR]

The research aims to study phospholipids (PL) classes and molecular species of large yellow croaker ( Pseudosciaena crocea ) roe. Both gas chromatographymass spectroscopy (GC-MS) and high-performance liquid chromatography with evaporative light-scattering detection (HPLC-ELSD) were utilized to analyze and identify the PLs fatty acids compositions and classes in the P. crocea roe, respectively. Docosahexaenoic acid (DHA, C22:6) and eicosapentaenoic acid (EPA, C20:5) account for 35.0% and 6.9% of the PLs. Phosphatidylcholines (PC), lysophosphatidylcholines (LPC), phosphatidylethanolamines (PE) and phosphatidylinositols (PI) account for 76.36 ± 0.62%, 12.30 ± 0.55%, 9.12 ± 0.02% and 1.09 ± 0.01% of the total PLs, respectively. In addition, the PLs molecular species were characterized by ultra-high performance liquid chromatography-electrospray ionization-quadruple-time of flight-mass spectrometry (UPLC-Q-TOF-MS). A total of 92 PLs molecular species was identified, including 49 PCs, 13 PEs, 10 phosphatidic acids (PAs), 13 phosphatidylserines (PSs), 3 phosphatidylglycerols (PGs), 2 sphingomyelins (SMs), and 2 PIs of the P . crocea roe. [ABSTRACT FROM AUTHOR]

In capacitive deionization (CDI), the functionalization or modification of carbon electrodes and the mitigation of positive electrode oxidation are effective methods to improve desalination capacity and stability for practical application. Here, the covalent bond attached three-dimensional (3D) graphene/carbon nanotubes hybrid (G-CNTs) with rich conductive channels was chosen as electrode material, and a periodically alternated (positive and negative) voltage operation (1.2/0/–1.2/0 V) was applied that aims to enhance the efficiency and stability of capacity deionization. The desalination capacity of the G-CNTs electrode increased gradually over the first few cycles in this operation, while the usage cycle of CDI could be pronouncedly extended almost six times, compared with the CDI of regular applied voltage operation (1.2/0 V). Through the characterization of electrode and CDI cell, this enhancement of the desalination performance is attributed to the synergistic benefits of alternating oxidation of negative and positive electrode, which can mitigate the oxidation of the positive electrode as well as achieve negative surface charge enhanced negative electrode. Therefore, a periodically alternated voltage operation is an economical and efficient method to control the oxidation of electrodes for enhancing the desalination performance. [ABSTRACT FROM AUTHOR]

This study was designed to observe the effects of maternal food restriction (MFR) on the development of fetal thymus in different gestation periods. Timed pregnant rats were randomized into 3 groups: CN (free access to standard chow throughout gestation), MFR 0-21 (50% MFR throughout gestation), MFR 0-14 (50% MFR from gestational day (GD) 0 to GD14, early-mid gestation). Results showed that MFR during early-mid period had few impact on the fetal thymus and T cell subpopulations. However, MFR throughout gestation resulted in thymic atrophy, deceased frequency of both CD4 + and CD8 + single positive (SP) T cells and enhanced thymocyte apoptosis in fetus. Our results suggest the fetal thymus is more vulnerable to the adverse intrauterine environments in the late gestation period, and the decreased number of SP T cells could result from the enhanced thymocyte apoptosis. [ABSTRACT FROM AUTHOR]

Flow-electrode capacitive deionization (FCDI) is a new desalination technology that delivers sustainable desalination performance. However, higher desalination rate and charge efficiency of FCDI are still desired for practical applications. In this study, voltages greater than 1.23 V – the minimum voltage for water electrolysis – were applied to enhance the driving force for ion migration and adsorption in an FCDI so as to achieve higher desalination rates. When the voltage was raised from 0.6 to 4.8 V, the desalination rate increased by nearly 7 times but the charge efficiency reduced from 92% to 69.5% due to the occurrence of Faradaic reactions such as water electrolysis. The other major factor that influenced the FCDI's charge efficiency was found to be concentration diffusion of ions between the FCDI's middle chamber and the two electrode chambers. To improve the charge efficiency, carbon black (CB) particles with an average diameter of 12 μm were added to the activated carbon flow electrodes at a mixing ratio of 1.5 wt%. With that, the FCDI's charge efficiency increased from 83.5% to 96.5% at 2.4 V. Electrochemical impedance spectrometry (EIS) analysis indicates that the addition of CB particles significantly reduced the FCDI's internal resistance, thereby leading to enhanced desalination performance. [ABSTRACT FROM AUTHOR]

To explore the sulfur transformation in the grading utilization of coal, the forms and distributions of sulfur at different operation parameters and foreign minerals were investigated in coal pyrolysis with solid heat carrier and combustion, respectively. The results show that the increasing pyrolysis temperature increases the sulfur content in the gaseous phase. For the coal with larger particle size, more sulfur will residue in char. The change of the mass ratio of quartz sand to coal and heating rate have little effect on the sulfur distribution in gas, tar and char products. After 3 wt% CaO is introduced to the raw coal, sulfur in gas and tar decreases from 29.68 and 12.16 wt% of the raw coal to 22.31 and 10.66 wt%, respectively. Fe 2 O 3 mainly affects the migration of gaseous sulfur to solid phase sulfur during coal pyrolysis. MgO, NaOH, and KOH have no sulfur fixation effect. The sulfur-fixed efficiencies for 3 wt% CaO and 3 wt% Fe 2 O 3 are 17.17 and 38.16 wt%, respectively. When the contents of CaO and Fe 2 O 3 increase, the sulfate sulfur and sulfide sulfur in the char increase, and the sulfur fixed in ash which obtained from the combustion of char increases. The inhibitory effect of CaO on the secondary release of SO 2 in the combustion stage is stronger than that of Fe 2 O 3 . This paper provides a basic reference for the removal of sulfur during the step conversion of coal pyrolysis and combustion. [ABSTRACT FROM AUTHOR]

The traditional microbial fuel cell (MFC) sensor with bioanode as sensing element delivers limited sensitivity to toxicity monitoring, restricted application to only anaerobic and organic rich water body, and increased potential fault warning to the combined shock of organic matter/toxicity. In this study, the biocathode for oxygen reduction reaction was employed for the first time as the sensing element in MFC sensor for toxicity monitoring. The results shown that the sensitivity of MFC sensor with biocathode sensing element (7.4±2.0 to 67.5±4.0 mA% −1 cm −2 ) was much greater than that showed by bioanode sensing element (3.4±1.5 to 5.5±0.7 mA% −1 cm −2 ). The biocathode sensing element achieved the lowest detection limit reported to date using MFC sensor for formaldehyde detection (0.0005%), while the bioanode was more applicable for higher concentration (>0.0025%). There was a quicker response of biocathode sensing element with the increase of conductivity and dissolved oxygen (DO). The biocathode sensing element made the MFC sensor directly applied to clean water body monitoring, e.g., drinking water and reclaimed water, without the amending of background organic matter, and it also decreased the warning failure when challenged by a combined shock of organic matter/toxicity. [ABSTRACT FROM AUTHOR]

With the aim of improving the compatibility, high and low temperature properties of SBR modified asphalt, polyphosphoric acid (PPA) was added to achieve a further modification in this study. The effects of PPA and asphalt composition on physical properties, viscoelastic behavior, creep and recovery behavior, cracking resistance, compatibility and morphology of PPA/SBR modified asphalt were characterized, respectively. It was demonstrated that PPA dramatically enhanced the adhesion ability, high temperature elasticity and anti-rutting ability of SBR modified asphalt through deflocculation effect. The resistance against low temperature cracking of PPA/SBR modified asphalt underwent a degradation after first improvement as PPA increased. PPA also improved the compatibility between SBR and asphalt and decreased the dispersed polymer phase size, thus a more desirable microstructure was formed. Furthermore, relatively high asphaltene content of base asphalt was beneficial to achieve desired rheological properties of PPA/SBR modified asphalt. As a consequence, chemical reaction with PPA is an effective way to comprehensively improve the compatibility and thermo-rheological behavior of SBR modified asphalt. [ABSTRACT FROM AUTHOR]

The use of biosensors for water alert system is critical for providing safe water to the general public. A cathode-shared microbial fuel cell (MFC) sensor array was designed improve the detection credibility by eliminating the cathode performance variation, based on the principle that only the bioanode would be used as the sensing and transducing element. Four integrated MFCs exhibited high parallelism, and independence without the cross contamination or electric signal interference. Two linear ranges were observed (from 0.25 to 0.75 mM and from 1 to 10 mM) for acetate detection. A linear relationship between inhibition ratio ( IR ) and Cu 2+ concentration from 2 to 6 mg/L was recorded. The sensor expressed an immediate voltage decrease when exposed to a pH decrease from 6 to 4. The compact design of the cathode-shared MFC sensor array assure the detection credibility, and the number of the integrated MFC sensors is alterable based on the monitoring requirement. [ABSTRACT FROM AUTHOR]

A binder-free, pseudocapacitive anode was fabricated by coating reduced graphene oxide (rGO) and manganese oxide (MnO 2 ) nanoparticles on stainless steel fibre felt (SS). Microbial fuel cell (MFC) equipped with this novel anode yielded a maximum power density of 1045 mW m −2 , 20 times higher than that of a similar MFC with a bare SS anode (46 mW m −2 ). Transient-state regulation (TSR) was implemented to further improve the MFC’s power generation. The optimal TSR duty cycle ranged from 67% to 95%, and the MFC’s power density increased with TSR frequency. A maximum power density output of 1238 mW m −2 was achieved at the TSR duty cycle of 75% and the frequency of 1 Hz, 18.4% greater than that obtained from the steady state operation. The TSR mode delivered better MFC performance especially when the external resistance was small. Long-term operation tests revealed that the current density and power density yielded in the TSR mode were on average 15.0% and 32.7% greater than those in the steady state mode, respectively. The TSR mode was believed to reduce the internal resistance of the MFC while enhance substrate mass transfer and electron transfer within the anode matrix, thereby improving the MFC performance. [ABSTRACT FROM AUTHOR]

GINS2, a subunit of GINS complex, is critical for the initiation of DNA replication and DNA replication fork progression. The expression of GINS2 is misregulated in many malignant tumors, such as leukemia, breast cancer and melanoma. However, the role of GINS in breast cancer remains poorly characterized. We investigate the possible effect and particular mechanism of GINS in breast cancer cells. We showed that expression of GINS2 is enriched in triple negative breast cancer (TNBC) cell lines. Furthermore, GINS2 knockdown decreased the growth, invasive ability and stem-like property of TNBC cells. Mechanistically, silencing of GINS2 in TNBC cells caused dramatic decrease of matrix metalloproteinase-9 (MMP9). Finally, the abundance of GINS2 correlated with the advance stages of tumor in human TNBC patients. Our studies provided insight into the molecular regulation of TNBC progression and invasion. More importantly, our data suggest that GINS2 could be an outstanding therapeutic target for inhibiting invasive TNBC growth and metastasis. [ABSTRACT FROM AUTHOR]

In environmentally sensitive areas, particularly the arid or semi-arid regions, different factors such as relief and human activity, can greatly influence the landscape on a local scale. Using satellite imageries and field investigations, we have studied the distribution of sand dunes in the Maowusu (Mu Us) Sandy Land in the southern Ordos Plateau, northern China. Key research questions are which factors are critically responsible for the spatial pattern evident in the landscape and what is the relative importance of such factors? We used a new approach, i.e., the Geographical Detector to improve our spatial analysis. Using the combined methods of the Geographical Detector, digital image processing, field investigation and spatial and temporal analysis of the Normalized Difference Vegetation Index (NDVI), we aimed to clarify the causal relations governing the different landform patterns within this Sandy Land and beyond. The primary factors include local relief, drainage, climatically controlled potential plant productivity, wind action and rock type as explanatory parameters x and the landscape properties as the output y . Our results show the quantified links between the spatial distribution of various landscapes and their controlling factors. This study revealed that the climatic potential productivity, local relief and drainage are the key factors in shaping the landscape spatial pattern. Owing to different regional climates and land use histories, the responses to changes of external forcing between the western and eastern parts of the Maowusu Sandy Land are out-of-step. We conclude that the desertification of the eastern part of Maowusu Sandy Land has been mainly caused by human activities while the western part is governed by natural factors. [ABSTRACT FROM AUTHOR]

Bioelectrochemical systems (BESs) are integrated water treatment technologies that generate electricity using organic matter in wastewater. In situ use of bioelectricity can direct the migration of ionic substances in a BES, thereby enabling water desalination, resource recovery, and valuable substance production. Recently, much attention has been placed on the microbial desalination cells in BESs to drive water desalination, and various configurations have optimized electricity generation and desalination performance and also coupled hydrogen production, heavy metal reduction, and other reactions. In addition, directional transport of other types of charged ions can remediate polluted groundwater, recover nutrient, and produce valuable substances. To better promote the practical application, the use of BESs as directional drivers of ionic substances requires further optimization to improve energy use efficiency and treatment efficacy. This article reviews existing researches on BES-driven directional ion transport to treat wastewater and identifies a few key factors involved in efficiency optimization. [ABSTRACT FROM AUTHOR]

Sulfur transformation in the polygeneration process of Xinzhou high-sulfur coal employing a circulating ash heat carrier was studied using a fixed bed reactor. Circulating ash was effective in capturing the gaseous sulfur, along with ~ 80% of H 2 S, 59% of COS, 55% of CS 2 , and 48% of SO 2 . Sulfur mass balance calculations revealed that 30.88% of the total sulfur content was retained in the circulating ash at 600 °C. The sulfur retention capacity of the ash was promoted by an increase in temperature, an increase in the ash to coal mass ratio, and a decrease in ash particle size. Sulfur captured in the circulating ash released lower quantities of SO 2 than the sulfur remaining in the char during combustion. Furthermore, CaO and Fe 2 O 3 played a dominant role in the sulfur retention of the circulating ash, and the sulfur retention capacity of Fe 2 O 3 was superior to that of CaO during pyrolysis. X-ray diffraction results indicated that the sulfur captured by CaO and Fe 2 O 3 was converted into CaS and FeS. However, FeS was easily oxidized to Fe 2 O 3 , accompanied by the emission of SO 2 , while CaS tended to be oxidized to CaSO 4 during combustion. [ABSTRACT FROM AUTHOR]

• The mechanisms for organocatalytic synthesis of chiral allene by racemic propargylic alcohol and 3-phenylindole were proposed. • Eight possible reaction pathways were found after the dehydration process. • The intermolecular interactions including HBs and π-π interactions play crucial roles in determining the enantioselectivity. Organocatalytic synthesis of chiral allene can be successfully achieved through the reaction between propargylic alcohol and 3-phenylindole catalyzed by chiral phosphoric acid with high yield and high enantioselectivity. The detailed reaction mechanism and origin of enantioselectivity were uncovered by quantum mechanical calculations. The results indicate that the reactions undergo the dehydration process, the C–C bonding reaction, the hydrogen abstraction and the regeneration of catalyst. Eight possible pathways were found and the most favorable reaction paths leading to the major and minor products were evaluated which were consistent with the experimental results. The distortion/interaction analyses of the transition states in enantioselectivity-determining steps confirm the most favorable pathway in leading the major product. QTAIM and IGM analyses are used to illustrate the role of intermolecular interactions. EDA analysis is also employed to understand the origin of selectivity. This work would provide insightful viewpoints on the asymmetric organocatalytic reaction by chiral phosphoric acid. [Display omitted] [ABSTRACT FROM AUTHOR]

A novel anode was developed by coating reduced graphene oxide (rGO) and manganese oxide (MnO 2 ) composite on the carbon felt (CF) surface. With a large surface area and excellent electrical conductivity, this binder-free anode was found to effectively enhance the enrichment and growth of electrochemically active bacteria and facilitate the extracellular electron transfer from the bacteria to the anode. A microbial fuel cell (MFC) equipped with the rGO/MnO 2 /CF anode delivered a maximum power density of 2065 mW m −2 , 154% higher than that with a bare CF anode. The internal resistance of the MFC with this novel anode was 79 Ω, 66% lower than the regular one's (234 Ω). Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) analyses affirmed that the rGO/MnO 2 composite significantly increased the anodic reaction rates and facilitated the electron transfer from the bacteria to the anode. The findings from this study suggest that the rGO/MnO 2 /CF anode, fabricated via a simple dip-coating and electro-deposition process, could be a promising anode material for high-performance MFC applications. [ABSTRACT FROM AUTHOR]

Hypoxia-induced cerebrovascular dysfunction is a key factor in the occurrence and the development of cerebral ischemia. Na + , K + -ATPase affects the regulation of intracellular Ca 2 + concentration and plays an important role in vascular smooth muscle function. However, the potential role of Na + , K + -ATPase in hypoxia-induced cerebrovascular dysfunction is unknown. In this study, we found that the KCl-induced contraction under hypoxia in rat endothelium-intact basilar arteries is similar to that of denuded arteries, suggesting that hypoxia may cause smooth muscle cell (SMC)-dependent vasoconstriction in the basilar artery. The Na + , K + –ATPase activity of the isolated basilar artery with or without endothelium significantly reduced with prolonged hypoxia. Blocking the Na + –Ca 2 + exchanger with Ni 2 + (10 − 3 M) or the L-type Ca 2 + channel with nimodipine (10 − 8 M) dramatically attenuated KCl-induced contraction under hypoxia. Furthermore, prolonged hypoxia significantly reduced Na + , K + -ATPase activity and increased [Ca 2 + ] i in cultured rat basilar artery SMCs. Hypoxia reduced the protein and mRNA expression of the α 2 isoform of Na + , K + -ATPase in SMCs in vitro . We used a low concentration of the Na + , K + -ATPase inhibitor ouabain, which possesses a high affinity for the α 2 isoform. The contractile response in the rat basilar artery under hypoxia was partly inhibited by ouabain pretreatment. The decreased Na + , K + -ATPase activity in isolated basilar artery and the increased [Ca 2 + ] i in SMCs induced by hypoxia were partly inhibited by pretreatment with a low concentration of ouabain. These results suggest that hypoxia may educe Na + , K + -ATPase activity in SMCs through the α 2 isoform contributing to vasoconstriction in the rat basilar artery. [ABSTRACT FROM AUTHOR]

Reducing the energy consumption of membrane bioreactors (MBRs) is highly important for their wider application in wastewater treatment engineering. Of particular significance is reducing aeration in aerobic tanks to reduce the overall energy consumption. This study proposed an in situ ammonia-N-based feedback control strategy for aeration in aerobic tanks; this was tested via model simulation and through a large-scale (50,000 m 3 /d) engineering application. A full-scale MBR model was developed based on the activated sludge model (ASM) and was calibrated to the actual MBR. The aeration control strategy took the form of a two-step cascaded proportion-integration (PI) feedback algorithm. Algorithmic parameters were optimized via model simulation. The strategy achieved real-time adjustment of aeration amounts based on feedback from effluent quality (i.e., ammonia-N). The effectiveness of the strategy was evaluated through both the model platform and the full-scale engineering application. In the former, the aeration flow rate was reduced by 15–20%. In the engineering application, the aeration flow rate was reduced by 20%, and overall specific energy consumption correspondingly reduced by 4% to 0.45 kWh/m 3 -effluent, using the present practice of regulating the angle of guide vanes of fixed-frequency blowers. Potential energy savings are expected to be higher for MBRs with variable-frequency blowers. This study indicated that the ammonia-N-based aeration control strategy holds promise for application in full-scale MBRs. [ABSTRACT FROM AUTHOR]

Thirty-six sediment samples were collected from six mariculture sites and corresponding reference sites (approximately 200–300 m away from each mariculture site) to study the effects of mariculture on heavy metal: copper (Cu), zinc (Zn), chromium (Cr) and lead (Pb) distribution in sediments and cultured fish around the Pearl River Delta region, south China. The mean concentrations of Cu, Zn, Cr and Pb in all mariculture sediment samples were 109, 273, 99 and 33 mg/kg, compared with 63, 209, 56 and 23 mg/kg for reference sediment samples, respectively. The Pollution Load Index of sediment for each site was over 1, implying substantial heavy metal pollution. The results of principal component analysis and hierarchical clustering analysis indicate that marine aquaculture activities have enriched the surface sediments underneath mariculture rafts with Cu, Zn and Pb, possibly due to the accumulation of unconsumed fish feeds, fish excreta and antifouling paints (except Cr). Two kinds of fish feeds, feed pellets and trash fish commonly used in Hong Kong were analyzed. The concentrations of Zn and Cu contained in feed pellets were significantly higher ( p < 0.05) than in trash fish due to addition of these elements as growth promoters during pellet production. However, the Pb content in trash fish (due to contamination) was significantly higher ( p < 0.05) than in feed pellets. Three cultured fish species, namely red snapper ( Lutjanus campechanus ), orange-spotted grouper ( Epinephelus coioides ) and snubnose pompano ( Trachinotus blochii ), were collected from each mariculture site for metal analysis. Lead concentrations in 21 fish samples exceeded the Chinese safety guideline (0.5 mg/kg, GB18406.4–2001), indicating that Pb contamination in cultured fish would be a public health concern. [ABSTRACT FROM AUTHOR]

A successful pH control is of critical importance for ensuring efficient H 2 production in two-chamber MECs. In this study, a novel two-chamber MEC is developed with biotic/abiotic hybrid electrodes, which are composed of carbon felt (CF) and stainless steel (SS) mesh. The CF is used for the electrogenic microorganisms attachment catalyzing the oxidation of organic matter (OM); the SS serves as the current collector and the H 2 evolution catalyst. The MEC is operated in the periodic polarity reversal (PPR) mode and two hybrid electrodes work alternately as an anode and a cathode. With the hybrid electrodes and the PPR mode, the pH fluctuation is limited within the range of 6.4–8.6, and the H 2 production is 5.3 times that of control without the PPR mode. The optimal reversal interval is 2 h for maximal H 2 production. The H 2 production increases with the amplitude of the applied voltage (0.7–1.0 V). The using of hybrid electrodes, combining with the PPR mode, provides a simple but efficient pH control strategy and better H 2 production performance in MECs. The findings of this study are expected to facilitate the design of pilot-scale MECs or similar bio-electrochemical reactors in future research. [ABSTRACT FROM AUTHOR]

Previous investigations on membrane capacitive deionization (MCDI) cells focused on electrode and membrane materials; while little attention has been paid to the separator compartment. This study demonstrated that the MCDI's desalination rate can be enhanced by inserting activate carbon fibers (ACF) in the cell's separator compartment. For comparison, stainless steel fibers (SSF) and filter paper (FP) were also examined as the separator. The highest desalination rate [513.4 mg/(L·h)] was obtained when ACF was inserted, followed by SSF [374.1 mg/(L·h)] and FP [297.9 mg/(L·h)]. The pseudo-first-order kinetic model provided a good approximation ( R 2 > 0.99) to the measured adsorption data, and the model fitting results revealed that the MCDI with the ACF separator delivered not only the highest desalination rate but also the largest adsorption capacity. Electrochemical impedance spectrometry (EIS) analysis revealed that the ACF separator considerably reduced the MCDI's internal resistance and accordingly increased its desalination rate. Our findings highlight the need for revisiting and modifying the current designs of the MCDI's separator compartment. [ABSTRACT FROM AUTHOR]

The application of microbial fuel cell (MFC)-based toxicity sensors to real-world water monitoring is partly impeded by the limited sensitivity. To address this limitation, this study optimized the flow configurations and the control modes. Results revealed that the sensitivity increased by ∼15–41 times with the applying of a flow-through anode, compared to those with a flow-by anode. The sensors operated in the controlled anode potential (CP) mode delivered better sensitivity than those operated in the constant external resistance (ER) mode over a broad range of anode potentials from −0.41 V to +0.1 V. Electrodeposition of Cu(II) was found to bias the toxicity measurement at low anode potentials. The optimal anode potential was approximately −0.15 V, at which the sensor achieved an unbiased measurement of toxicity and the highest sensitivity. This value was greater than those required for electrodeposition while smaller than those for power overshoot. [ABSTRACT FROM AUTHOR]

Using microbial fuel cells (MFCs) to power a capacitive deionization (CDI) process enables simultaneous removal of salinity and organic matter in wastewater. The desalination performance of an MFC-CDI system can be influenced by not only the capacity of individual components but also the arrangement and operation of the MFC-CDI circuit. Five typical circuits (consisting of serial- or parallel-connected MFCs or CDIs) and two ion-desorption modes (short-circuit and reverse-voltage desorption) were compared. Results showed that the MFC-CDI system could be reasonably modeled (R 2 > 0.967) by a first-order resistor–capacitor circuit. The optimal arrangement of the MFC-CDI circuit depended on the electrical characteristics of selected MFCs and CDIs as well as operating conditions. When the system was powered by two MFCs of a larger internal resistance (146 Ω), the highest salt removal after 60 min ( m 60 ; 7.5 mg) was achieved by paralleling the two MFCs; with MFCs of a smaller resistance (12 Ω) being used, the highest m 60 (16.5 mg) was obtained when the two MFCs were connected in series. Further analysis revealed that the MFC's internal resistance and open-circuit voltage, along with the CDI's internal resistance and capacitance, were the chief factors affecting the charge transfer and accordingly desalination on the CDI electrodes. [ABSTRACT FROM AUTHOR]

• Modified Modal Observability Correlation is proposed to distinguish different modes. • New spurious mode elimination method is proposed to clear the stabilization diagram. • New fully automated modal identification and tracking method is proposed. • The proposed method can be used for closely spaced modes with spatial aliasing. Automated modal identification and tracking provides the key technique for modal parameters based structural condition evaluation. However, the existing automated modal identification and tracking methods have limitations for situation with very few sensors deployed and require manual intervention. This paper proposes a unified fully automated modal identification and tracking method that can be used for structures with many or very few sensors deployed, for closely spaced modes with severe spatial aliasing and for structures with high flexibility or rigidity. A new index, which is called Modified Modal Observability Correlation, is proposed to estimate the similarity of two modes. New spurious mode elimination method and fully automated mode separation and tracking methods are proposed to realize the automated modal identification and tracking. The feasibility and novelty of the proposed method are validated using in-field monitoring data from a long span suspension bridge with high flexibility and a short span bridge with high rigidity and closely spaced modes. Automated modal identification and tracking for situations with many and very few sensors deployed for the two bridges are conducted, and extreme situation of closely spaced modes with spatial aliasing in mode shape is also considered to prove the novelty of the proposed method. Comparisons with existing mainstream methods are also conducted. The results show that the proposed method yields the right identification and tracking results in all situations, showing novelty in automated modal identification and tracking for structures with closely spaced modes having severe spatial aliasing when only very few sensors are deployed. [ABSTRACT FROM AUTHOR]

• An automatic identification method of abnormal vibrations for stay-cables is proposed. • Two feature indices distinguishing the VIV from ambient vibration are proposed. • Minimum Euclidean Distance Classifier is utilized to automate the identification process. • Field monitoring data are used to validate the feasibility. Online automatic monitoring of abnormal vibrations, such as vortex-induced vibration (VIV) and high amplitude vibration (HAV), of stay-cables is important for bridge maintenance. However, the existing methods either require manual intervention or yield unreasonable identification results and are not suitable for online automatic monitoring. This study proposes a fully automatic method to identify the abnormal vibrations of stay-cables based on acceleration data. Two quantified feature indices are extracted from frequency domain and complex domain to characterize the VIV. A feature vector is established to distinguish the VIV from ambient vibration, and Minimum Euclidean Distance Classifier is utilized to automate the online identification process. The HAV is automatically identified based on root mean square of acceleration. The proposed method avoids any manual intervention and can yield correct and convincible identification results. Case study of a cable-stayed bridge finally validates the feasibility and novelty of the proposed method. [ABSTRACT FROM AUTHOR]

In this study, a microbial fuel cell (MFC) with granular activated carbon packed anode (GAC-MFC) is developed and compared with a MFC with granular graphite packed anode (GG-MFC), to evaluate the adsorptive effect of the granular activated carbon anode on MFC’s performance. The current output of GAC-MFC (11.1 mA, 18.1 mA and 21.6 mA) is much higher than that of GG-MFC (4.87 mA, 12.5 mA and 17.9 mA) at low substrate COD concentrations (∼50, ∼100 and ∼200 mg/L) when a low external resistance (20 Ω) and high circulation flow rate (20 mL/min) are applied. The half-saturation constant ( K s ) of GAC-MFC is about half as much as that of GG-MFC, suggesting that GAC-MFC has more affinity for anode substrate and deliver better kinetic performance than GG-MFC. Internal resistance distribution shows that mass diffusion resistance of GAC-MFC is at least 50% lower than that of GG-MFC when the substrate COD is ∼50 mg/L, indicating that the adsorptive effect of granular activated carbon packed anode helps to effectively facilitate mass transfer at low COD concentrations. Otherwise, the substrates adsorbed on GAC surface also serve to buffer the impact of COD concentration plummeting in bulk solution. [ABSTRACT FROM AUTHOR]

A novel anode is fabricated by electrodepositing manganese dioxide (MnO 2 ) on carbon felt to promote MFC's power production. Compared to the bare carbon felt anode, when the electrodeposition time increases to 60 min, the anode capacitance improves 46 times. The maximum power density of the MFC with the MnO 2 -coated anode reaches 3580 ± 130 mW m −2 , 24.7% higher than that with the bare carbon felt anode (2870 mW m −2 ). MnO 2 is believed to facilitate extracellular electron transfer and accordingly improve the power output. Three anode substrate circulation modes, i.e., flow-through, side-flow, and no-flow, are applied. Electrochemical impedance spectroscopy (EIS) tests reveal that flow-through mode decreases the anode mass transfer resistance by 41.4% compared to the no-flow mode and contributes to the MFC's power production improvement. [ABSTRACT FROM AUTHOR]

Abstract: A new analytical method is proposed to calculate the static performance of hydrostatic journal bearing. Analytical expressions of recess pressure and flow are deduced through analyzing flow continuity equation and utilizing Gauss–Legendre integral formula. To study the computational accuracy and the application range of the new method, recess pressure and flow of a four-pocket capillary compensated hydrostatic bearing under different eccentricity ratios and wrap angles of oil recess are calculated using three methods (the new method, the old analytical method and the finite difference method). The results indicate that new analytical method has the advantage of simplicity and high computational accuracy. [Copyright &y& Elsevier]

Salvia miltiorrhiza is one of the most important traditional Chinese medicinal plants for its therapeutic effects. In the present study, morphological traits, ISSR (inter-simple sequence related) and SRAP (sequence-related amplified polymorphism) markers were used to analyze the genetic diversity of 59 S. miltiorrhiza phenotypes. Out of the 100 ISSR primers and 100 SRAP primer combinations screened, 13 ISSRs and 7 SRAPs were exploited to evaluate the level of polymorphism and discriminating capacity. The results showed that the 13 ISSRs generated 190 repeatable amplified bands, of which 177 (93.2%) were polymorphic, with an average of 13.6 polymorphic fragments per primer. The 7 SRAPs produced 286 repeatable amplified bands, of which 266 (93.4%) were polymorphic, with an average of 38.1 polymorphic fragments per primer. Cluster analysis readily separated different morphological accessions, wild and cultivated controls based on morphological traits, ISSR and SRAP markers. The study indicated that morphological traits, ISSR and SRAP markers were reliable and effective for assessing the genetic diversity of phenotypic S. miltiorrhiza accessions. The overall results suggested that the introduction of genetic variation from morphology-based germplasms enlarged the genetic base for the collection, conservation and further breeding program of S. miltiorrhiza germplasm. [ABSTRACT FROM AUTHOR]

The water-lubricated bearing in ship propulsion system is easily impacted by sea wave shock, which is a great threat to the smooth start-up of the bearing system. Therefore, in the present research, the Euler equations, average Reynolds equation, and sea wave shock function are combined together to build the start-up model of water-lubricated bearing. The influences of amplitude, direction, and entry time of sea wave shock on the start-up performance of bearing are studied. The result shows that the shaft has a strong instantaneous vibration under the influence of friction force at the initial start-up stage, and the shock load with appropriate direction and amplitude can suppress or even eliminate this vibration phenomenon. The earlier the shock enters the start-up process, the more serious asperity contact gets, and the worse the system's stability becomes. The increase of the shock load amplitude and the advance of the shock load entry time can help the shaft rapidly lift off. This study can provide a reference for the smooth start-up of ship propulsion system in a sea wave environment. • External force can be actively applied to suppress shaft vibration during start-up. • The later the shock load enters, the more conducive it is to smooth start-up. • With the increase of shock load amplitude, shaft's lift-off time shortens. [ABSTRACT FROM AUTHOR]