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Graph Neural Networks(GNNs) has dominated the semi-supervised node classification task by its neighborhood aggregation mechanism over traditional network embedding methods. However, GNNs still encounters with two vital problems when scales to large networks. It requires the whole graph as input and aggregates attribute only, which brings out-of-memory(OOM) problem on single machine scenery and attribute over-smoothing respectively. To tackle these issues, from the traditional view, we propose a Sequence correlation preserving method for Attributed Network E mbedding (SANE) which transforms the network properties into three types of sequences and preserves the correlations among them. Firstly, SANE extracts three types of sequences in attributed network, namely node sequence, attribute sequence, and label sequence, which provide distinct insight into networks. Secondly, the proposed method preserves attribute-node sequence correlation and attribute-label sequence correlation by (1) extracting dual-directional features from attribute sequence and (2) exploiting the extracted features to decode node sequence and label sequence. SANE can scale to large networks and relieve the over-smoothing causing by attribute only aggregation. Experimental results on five real-world datasets demonstrate that SANE outperforms the state-of-the-art methods.

A new hybrid system mainly composed of a dye-sensitized solar cell (DSSC), a solar selective absorber (SSA) and an absorption heat transformer (AHT) is theoretically put forward to harness the long wavelength sunlight transmitted through the DSSC. The models of both DSSC and AHT are adopted from the current literature and the condition enables the AHT to involve in heat upgrading is obtained. The model validations of DSSC and AHT are conducted using experimental data. Mathematical expressions of power output and efficiency for the hybrid system are formulated by taking a variety of irreversible losses into account. The effectiveness of the hybrid system is justified and evaluated. Maximum power density (MPD) and maximum energy efficiency (MEE) of the integrated system are, respectively, 158.2 W m−2 and 16.3 %, having evidently improvement compared to that of a single DSSC. A variety of operating conditions and design parameters affecting the hybrid system performance are studied. Numerical calculation results show that the working temperature, photoelectron absorption coefficient of DSSC and total heat-transfer area of the AHT have positive effects on the hybrid system performance. There exists an optimum TiO2 thin film thickness to optimize the hybrid system performance. However, a greater Schottky barrier has negative influence on the hybrid system performance. The results obtained here may provide some guidance for designing such a practical hybrid system.

To harvest the relatively high wavelength sunlight, a novel hybrid system coupling a thermally regenerative electrochemical cycle to a dye-sensitized solar cell is proposed. Efficiencies and power outputs of dye-sensitized solar cell and thermally regenerative electrochemical cycle are calculated, and the mathematical relationship between the electric current of thermally regenerative electrochemical cycle and the working current density of dye-sensitized solar cell is deduced. The power output and efficiency of the hybrid system are also derived considering multiple irreversible losses. The feasibility and effectiveness of the proposed hybrid system will be assessed by comparing the performances between the hybrid system and the single dye-sensitized solar cell. Numerical calculations show that the maximum efficiency and power density of the hybrid system allow 32.04% and 32.18% greater than that of the single dye-sensitized solar cell, respectively. Comprehensive parametric studies are undertaken to examine the dependences of the hybrid system performance on some operating conditions and microstructure parameters, including electrode porosity, photoelectron absorption coefficient, Schottky barrier, film thickness and internal resistance of thermally regenerative electrochemical cycle. The derived results may offer new insights into design and optimization of such an actual hybrid system.

A new combined system consisting of a high-temperature proton exchange membrane fuel cell (HT-PEMFC), a regenerator and a thermoelectric generator (TEG) is developed. The mathematical relationship between the HT-PEMFC operating current density and the TEG dimensionless current is derived, and the operating current density range of HT-PEMFC in which the TEG allowed to work is determined. Power output and efficiency of the combined system are formulated under different operating conditions. Compared with the stand-alone HT-PEMFC, the proposed combined system allows the equivalent power density to increase by 21%. The optimum criteria and general performance characteristics for the complete system are specified. Moreover, the effects of the operating current density, doping level, relative humidity, operating temperature, heat conductivity and figure of merit of the thermoelectric materials on the combined system performance characteristics are revealed. The obtained results may provide some theoretical insights into the design and integration of such an actual combined system.

A combined system model consisting of a high-temperature polymer electrolyte membrane fuel cell (HT-PEMFC), a regenerator and a thermoelectric generator (TEG) is proposed, where the TEG is applied to harness the generated waste heat in the HT-PEMFC for extra electricity production. The TEG considers not only the Seebeck effect and Peltier effect but also the Thomson effect. The mathematical expressions of power output, energy efficiency, exergy destruction rate and exergy efficiency for the proposed system are derived. The energetic and exergetic performance characteristics for the whole system are revealed. The optimum operating ranges for some key performance parameters of the combined system are determined using the maximum power density as the objective function. The combined system maximum power density and its corresponding energy efficiency and exergy efficiency allow 19.1%, 12.4% and 12.6% higher than that of a stand-alone HT-PEMFC, while the exergy destruction rate density is only increased by 8.6%. The system performances are compared between the TEG with and without the Thomson effect. Moreover, the impacts of comprehensive parameters on the system performance characteristics are discussed. The obtained results are helpful in developing and designing such an actual combined system for efficient and clean power production.

In addition to electricity generation, high-temperature proton exchange membrane fuel cells also produce numerous high-quality waste heat, which may be further used in combined cooling, heating and power systems. In this study, a new general model of an integrated system consisting of a high-temperature proton exchange membrane fuel cell, a regenerator and an absorption cycle is proposed for waste heat recovery, where the absorption cycle can be functioned as either an absorption heat pump for heating or an absorption refrigerator for cooling. Considering various irreversible losses within the system, mathematical expressions for the equivalent power output and efficiency of the proposed system are derived, from which the general performance characteristics are revealed and the optimum criteria are given. When the absorption cycle is operated in the heat pump mode or refrigerator mode, the maximum attainable power densities for the proposed system allow 33.41% and 19.34% greater than that of the sole high-temperature proton exchange membrane fuel cell system, respectively. Furthermore, the effects of the operating current density, operating temperature, doping level, relative humidity, heat leak and heat-transfer irreversibilities on the performance characteristics of the proposed system are discussed in detail. The results obtained in this paper may offer some theoretical help for the integration and design of such an actual system.

Fascioliasis is a foodborne zoonotic disease generally caused by the parasitic flukes Fasciola gigantica and Fasciola hepatica in class Trematoda. An "intermediate" Fasciola forms between F. gigantica and F. hepatica has been shown to exist. However, the relationships among F. gigantica, F. hepatica, and "intermediate" Fasciola forms remain unclear. In this study, we found five new polymorphic positions in 18S and 28S rDNAs sequences of "intermediate" Fasciola forms. According to the high-throughput sequencing results, all known 16 polymorphic positions of "intermediate" Fasciola forms show a clear and consistent tendency for F. gigantica or F. hepatica, and the percentages of the most frequently occurring bases were different in specimens. In the three ITS sequence fragments, hybrid-type base combinations of the polymorphic positions were detected, and the percentages of the most frequent base combinations were different in specimens too. In addition, interestingly, the newly detected ITS-802 position was not a traditional polymorphic position in "intermediate" Fasciola forms, and the bases in ITS-802 position are not same as the allele bases of F. gigantica or F. hepatica. Our results will be helpful to investigations into the molecular taxonomy, population genetics, and ecology of F. gigantica, F. hepatica, and "intermediate" Fasciola forms.

The waste heat from phosphoric acid fuel cells is available and suitable for additional power generation by means of organic Rankine cycles. A new hybrid system model is proposed by integrating a phosphoric acid fuel cell with an organic Rankine cycle, where the organic Rankine cycle model is modified in absence of complex working fluid properties. The energetic, exergetic and ecological performances for the phosphoric acid fuel cell-organic Rankine cycle hybrid system are evaluated based on thermodynamic laws and steady-state mathematical models. Numerical results show that maximum power output density and maximum ecological objective function density of the hybrid system are 6036.7 W m−2 (at 9470.8 A m−2) and 2913.1 W m−2 (at 7050.8 A m−2), which are increased about 25.2% and 57.5% by comparing to that of the single phosphoric acid fuel cell system, respectively. Optimum working regions of various performance parameters are determined considering the trade-offs between multiple optimization criteria. Furthermore, the impacts of the operating temperature, exchange current density, electrolyte thickness and pinch temperature ratio on the hybrid system performance are analyzed. The derived results may offer some help for understanding the energetic, exergetic and ecological performances of such an actual cogeneration system.

The fluorescence spectrum of paclobutrazol solutions and the apple juice - paclobutrazol mixed solutions are detected, which have a distinct characteristic peak at 341 nm. Regression analysis is performed on the fluorescence spectrum and its derivative spectrum of paclobutrazol solutions and the apple juice - paclobutrazol mixed solutions. The corresponding prediction model functions between the concentration and fluorescence intensity of two methods are obtained respectively. In the original spectrum mode of paclobutrazol solutions, the correlation coefficient is 0.9999 at 341 nm, the recovery rate is 99 %–103 %, the average recovery rate is 100.45 %, and the relative standard deviation (RSD) is 1.4506 %. In the derivative spectrum mode of paclobutrazol solutions, the correlation coefficient is 0.9998 at 321 nm, the recovery rate is 98 %–103 %, the average recovery rate is 100.3 %, and the relative standard deviation (RSD) is 1.7095 %. In the original spectrum mode of the apple juice - paclobutrazol mixed solutions, the correlation coefficient is 0.9999 at 341 nm, the recovery rate is 98 %–100 %, the average recovery rate is 99.625 %, and the relative standard deviation (RSD) is 0.5208 %. In the derivative spectrum mode of the apple juice - paclobutrazol mixed solutions, the correlation coefficient of paclobutrazol is 0.9992 at 321 nm, the recovery rate is 94 %–99 %, the average recovery rate is 97.000 %, and the relative standard deviation (RSD) is 2.2031 %. The experiment results show that the derivative spectrum could enhance the detailed characteristics of spectral scanning due to the advantages of narrow bands, high sensitivity and large amount of information. However, the derivative spectrum method has no significant advantage over the original fluorescence spectrum in the quantitative paclobutrazol prediction. Therefore, the modeling analysis could be performed on the original fluorescence spectrum at 341 nm directly. The research results in this paper provide experimental reference for the quantitative detection of pesticide residues.

According to the first and second laws of thermodynamics, energetic, exergetic and ecological performances of a high-temperature proton exchange membrane fuel cell (HT-PEMFC) using the polybenzimidazole membrane doped with phosphoric acid molecules as electrolyte are investigated in this study. Mathematical expressions for the energy efficiency, power output, exergy destruction rate, exergy efficiency, entropy production rate and ecological coefficient of performance of the HT-PEMFC are derived. Model validation shows that the adopted HT-PEMFC model is valid and reliable. Generic performance characteristics for the HT-PEMFC are revealed. Optimum operating regions for various performance parameters are given based on the optimization criterion of maximum power density. Furthermore, effects of some main operating conditions and designing parameters on the HT-PEMFC system performance are discussed in detail. The results indicate that a higher operating temperature and a greater doping level are significant to the HT-PEMFC system performance improvement, while the operating pressure and relative humidity have less impacts on the HT-PEMFC performance. This work considers both the energy benefit and loss from the point of view of preservation of natural resources and the results may provide some theoretical support for designing higher performance HT-PEMFC systems.

A new hybrid system that integrates a high-temperature proton exchange membrane fuel cell (HT-PMEFC), a regenerator and a two-stage thermoelectric generator (TTEG) is put forward, where the TTEG takes Peltier effect, Seebeck effect and Thomson effect into account. The mathematical expressions for the power output, exergy destruction rate, electric efficiency and exergetic efficiency of the hybrid system and each component within the hybrid system are specified. The relationships between the working current density of HT-PEMFC and the electric current and the inter-stage temperature of the TTEG are obtained. Calculation results indicate that the HT-PEMFC/TTEG hybrid system allows its maximum power density and the corresponding electric efficiency and exergetic efficiency to increase by 11.8%, 17.5% and 17.7% with respect to the sole HT-PEMFC system, respectively. Furthermore, the corresponding exergy destruction rate density for the proposed hybrid system decreases by 11.4% as well. The optimum operating regions and the impacts of Thomson effect on the hybrid system energetic/exergetic performances are revealed. In the end, the influences of some decisive working conditions and designing parameters on the energetic and exergetic performances of the hybrid system are discussed.

High-temperature polymer electrolyte membrane fuel cells have a promising prospect in combined heat and power applications because their relatively high operating temperature. In this paper, a new combined system comprised of a high-temperature polymer electrolyte membrane fuel cell, a regenerator and a thermally regenerative electrochemical cycle subsystem is proposed, where the thermally regenerative electrochemical cycle subsystem further converts the waste heat from the high-temperature polymer electrolyte membrane fuel cell into electricity. Considering various electrochemically and thermodynamically irreversible losses within each subsystem and between them, mathematical formulas for power output, energy efficiency, exergy destruction rate and exergy efficiency of the combined system are formulated. The energetic and exergetic performance characteristics of the combined system are revealed and the optimum operating ranges are determined using maximum power density as objective function. Results show that the maximum output power density of the proposed system is improved by 15.6% compared with that of a single high-temperature polymer electrolyte membrane fuel cell, and its corresponding energy efficiency and exergy efficiency are also increased by 8.5% and 11.7%, respectively. Moreover, the effects of decisive operating conditions and designing parameters on the combined system performance are discussed in detail.