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The process effect of coagulation and precipitation is an important factor affecting the quality and economic cost of wastewater treatment, but it is very difficult to automatically control the dosage due to its nonlinear and large lag characteristics. Model prediction method will be the main direction to deal with nonlinearity and lag. In the process of coagulation and precipitation, the morphological characteristics of the floc reflect the quality of the flocculation, which has a great influence on the effluent quality. However, many modeling studies only use the water quality parameters of the previous moment to predict the effluent quality of the current moment, without considering the continuity of the flocculation precipitation process and the information represented by the floc image. The purpose of this paper is to solve the problem of precise dosing during coagulation and precipitation, save dosing cost. In this study, a self-built continuous coagulation and precipitation experimental system based on machine vision was used to conduct experiments and collect data, a self-written image processing program was used to quantitatively analyze the flocculation effect. LSTM model and Transformer model were used for training. The results showed that the deep learning model using time series data and flocs feature parameters had higher prediction accuracy, and both models achieved more accurate prediction (R2>0.95). The results of this study provide a new direction for the model predictive control of coagulation-precipitation process and precise dosing. • A continuous flow coagulation sedimentation experimental system based on visual recognition was designed in this study. • Based on fractal theory, the representative characteristic parameters of floc will be selected. • The deep learning model which is more consistent with the continuous coagulation and precipitation process is constructed. • The hyperparameters of the model are optimized, and the prediction effect of the deep learning model is excellent. [ABSTRACT FROM AUTHOR]

Diabetic cardiomyopathy (DCM) is a serious complication of diabetes mellitus that eventually progresses to heart failure. The sarco(endo)plasmic reticulum calcium ATPase 2a (SERCA2a), an important calcium pump in cardiomyocytes, is closely related to myocardial systolic-diastolic function. In mammalian cells, hydrogen sulfide (H 2 S), as a second messenger, antioxidant, and sulfurizing agent, is involved in diverse biological processes. Despite the importance of H 2 S for protection against DCM, the mechanisms remain poorly understood. The aim of the present study was to determine whether H 2 S regulates intracellular calcium homeostasis by acting on SERCA2a to reduce cardiomyocyte apoptosis during DCM. Db/db mice were injected with NaHS for 18 weeks. Neonatal rat cardiomyocytes (NRCMs) were treated with high glucose, palmitate, oleate, and NaHS for 48 h. Compared to the NaHS-treated groups, in vivo and in vitro type 2 diabetic models both showed reduced intracellular H 2 S content, reduced cystathionine γ-lyase (CSE) expression, impaired cardiac function, decreased SERCA2a expression and decreased SERCA2a activity, reduced SUMOylation of SERCA2a, increased sentrin-specific protease 1 (SENP1) expression, and disruption of calcium homeostasis leading to activation of the mitochondrial apoptosis pathway. Compared to the NaHS-treated type 2 diabetes cellular model, overexpression of SENP1 C683A reduced the S-sulfhydration of SENP1, reduced the SUMOylation of SERCA2a, reduced the increased expression and activity of SERCA2a, and induced mitochondrial apoptosis in cardiomyocytes. These results suggested that exogenous H 2 S elevates SENP1 S-sulfhydration to increase SERCA2a SUMOylation, improve myocardial systolic-diastolic function, and decrease cardiomyocyte apoptosis in DCM. [Display omitted] • H 2 S content is reduced in diabetic cardiomyopathy. • Reduced the SUMOylation of SERCA2a in diabetic cardiomyopathy leads to decreased expression and activity of SERCA2a and imbalance in cellular calcium homeostasis. • H 2 S can S-sulfhydration the 683 cysteine site in the catalytic triad of SENP1. • Decreased S-sulfhydration of SENP1 Cys683 leads to decreased the SUMOylation of SERCA2a in diabetic cardiomyopathy. [ABSTRACT FROM AUTHOR]

The abuse of antibiotics has drawn wide attention owing to their potential risk in human health and ecosystem. As one of the most commonly used sulfonamide antibiotics, sulfamethoxazole (SMX) can hardly be removed by conventional wastewater treatment methods, and thus it has become one of the most frequently detected antibiotics in water environment. In this study, a new cobalt-based heterogeneous catalyst (Co-bHAP) was successfully prepared using the simple impregnation method with animal bone-derived hydroxyapatite (bHAP) as the support, and applied to activate peroxymonosulfate (PMS) for the degradation of SMX in water. The physicochemical properties of Co-bHAP catalyst were investigated by series of characterization methods, and the results showed that this catalyst has a rough and porous morphological structure, as well as homogeneously distributed active component, which is mainly in the form of Co 3 O 4. The developed Co-bHAP can provide abundant reaction active sites and exhibit excellent catalytic activity and stability in PMS activation. The kinetic constant of Co-bHAP activating PMS to degrade SMX is up to 0.1524 min−1, which is 4.5 times larger than that of bare Co 3 O 4. The SMX (20 mg/L) degradation efficiency within 30 min in Co-bHAP/PMS system reached as high as 98.7% and still maintained at 86% after 5 times consecutive operation, with slight cobalt ions leaching less than 0.1 mg/L. Based on radical quenching experiment, electron paramagnetic resonance (EPR) test and XPS analysis, the reaction mechanism was proposed. The balance among Co3+/ Co2+, O2−/O 2 and PMS decomposition in Co-bHAP/PMS system ensured the continuous generation of sulfate radical (SO 4 •–) and hydroxyl radical (HO•), both of which are responsible for SMX degradation, while SO 4 •– plays a leading role. In addition, four possible pathways of SMX degradation were proposed according to the eight detected intermediate products. All the results suggested that this catalyst could have a promising potential in activating PMS to degrade sulfonamide antibiotic pollutants in water. [Display omitted] • Co-bHAP catalyst was successfully prepared using porous animal-bone-derived HAP as support. • Co-bHAP exhibited excellent catalytic activity and stability in PMS activation. • SO 4 •– and HO• were responsible for SMX degradation in Co-bHAP/PMS system. • The degradation efficiency of SMX reached as high as 98.7%. [ABSTRACT FROM AUTHOR]

Hybridizing solar energy and coal-fired steam power plant is one of most attractive approaches of cost-efficient solar electricity in the present. By using the concentrated solar heat at around 300 °C to replace the bleed steam of the turbine for preheating feed-water of coal-fired steam cycle, higher solar-to-power efficiency is possibly achieved in that the conversion of solar to power can utilize higher-temperature steam cycle. In this paper, with the aid of exergy methodology, we derive expressions of the conversion of solar energy into power for such kind of solar hybrid plant, especially an explicit correlation is obtained for explaining solar-to-power efficiency. By using the derived expressions, we examine a typical hybrid solar system with 330 MW coal-fired power plant and evaluate thermal performance of solar-to-power. In addition, the influences of key operation parameters on the solar thermal performance are disclosed such as solar irradiation, incident angle and turbine load. The results obtained here would be expected to provide a possibility for designing and evaluating practical hybrid solar and coal-fired power plant. [ABSTRACT FROM AUTHOR]

Polypyrrole (PPy) and copper sulfide (CuS) have been successfully deposited on bacterial cellulose (BC) membranes to prepare nanofibrous composite electrodes of PPy/CuS/BC for flexible supercapacitor applications. The introduction of CuS remarkably improves the specific capacitance and cycling stability of BC-based electrodes. The specific capacitance of the supercapacitors based on the PPy/CuS/BC electrodes can reach to about 580 F g −1 at a current density of 0.8 mA cm −2 and can retain about 73% of their initial value after 300 cycles, while the PPy/BC-based device could retain only 21.7% after 300 cycles. This work provides a promising approach to fabricate cost-effective and flexible nanofibrous composite membranes for high-performance supercapacitor electrodes. [ABSTRACT FROM AUTHOR]

• A hybrid calibration method for structured light field system combining stereo vision method and phase to coordinate mapping method. • The subview of light field system is treated as pinhole model to build auxiliary Fringe Projection Profilometry. • Light ray fitting and plane fitting are implemented to improve the calibration accuracy. A typical structured light field system consists of a light field camera and a pattern projector. By combining Fringe Projection Profilometry and light field imaging technology, the phase distribution characteristics of each position and each angle of the scene under test could be obtained, thus providing more information dimensions, and therefore improving the robustness and dynamic range of three-dimensional (3D) measurement. System calibration is a decisive factor for high-efficiency and high precision measurement. However, the complicated structure and working method make the calibration of structured light field system usually costly and cumbersome. In this paper, we propose a hybrid calibration approach combining the flexibility of the stereo vision method and high precision characteristics of the phase-coordinate mapping method. The feasibility of the proposed method has been verified in actual experiments with typical 3D targets. [ABSTRACT FROM AUTHOR]

Study Objective To compare the effects of local anesthetic intraperitoneal nebulization with intraperitoneal instillation during laparoscopic ovarian cystectomy on postoperative morphine consumption and pain. Design Multicenter, randomized, case-control trial. Design Classification Canadian Task Force Classification I. Setting University hospitals in Italy. Patients One hundred forty patients scheduled for laparoscopic ovarian cystectomy. Interventions Patients were randomized to receive either nebulization of ropivacaine 150 mg before surgery or instillation of ropivacaine 150 mg before surgery. Nebulization was performed using the Aeroneb Pro device (Aerogen, Galway, Ireland). Measurements and Main Results One hundred forty patients were enrolled, and 123 completed the study. There was no difference between the 2 groups in average morphine consumption (7.3 ± 7.5 mg in the nebulization group vs 9.2 ± 7.2 mg in the instillation group; p = .17). Eighty-two percent of patients in the nebulization group required morphine compared with 96% in the instillation group (p < .05). Patients receiving nebulization had a lower dynamic Numeric Ranking Scale compared with those in the instillation group in the postanesthesia care unit postanesthesia care unit and 4 hours after surgery (p < .05). Ten patients (15%) in the nebulization group experienced shivering in the postanesthesia care unit compared with 2 patients (4%) in the instillation group (p = .035). Conclusion Nebulization of ropivacaine prevents the use of morphine in a significant proportion of patients, reduced postoperative pain during the first hours after surgery, and was associated with a higher incidence of postoperative shivering when compared with instillation. [ABSTRACT FROM AUTHOR]

This study discusses the thermodynamic performance of a solar-hybrid coal-fired power plant that uses solar heat with temperature lower than 300°C to replace the extracted steam from a steam turbine to heat the feed water. Through this process, the steam that was to be extracted can efficiently expand in the steam turbine to generate electricity. The flow rate of steam returning to the turbine retains only a small part of the main stream, allowing the steam turbine to run close to design conditions for all DNI. A solar-only thermal power plant without storage is also discussed to illustrate the advantages of a solar-hybrid coal-fired power plant. The off-design performances of both plants are compared based on the energy-utilization diagram method. The exergy destruction of the solar-hybrid coal-fired power plant is found to be lower than that of the solar-only thermal power plant. The comparison of two plants, which may provide detailed information on internal phenomena, highlights several advantages of the solar-hybrid coal-fired power plant in terms of off-design operation: lower exergy destruction in the solar feed water heater and steam turbine and higher exergy and solar-to-electricity efficiency. Preliminary technological economic performances of both plants are compared. The results obtained in this study indicate that a solar-hybrid coal-fired power plant could achieve better off-design performance and economic performance than a solar-only thermal power plant. [ABSTRACT FROM AUTHOR]

Highlights: [•] A rotatable-axis tracking parabolic-trough collector has been proposed. [•] Main optical and receiver losses have been disclosed. [•] Improvement of solar-field efficiency have been analyzed. [ABSTRACT FROM AUTHOR]

Abstract: In the current study, a new solar-driven triple cycle is proposed to allow power generation during low insolation periods. This triple cycle integrates the solar gas-turbine top cycle, the steam Rankine cycle, and the Kalina bottom cycle. During the top cycle of the proposed system, compressed air was heated to 1000 °C or higher in the solar tower receiver. The heated compressed air was then used to drive the gas turbine to generate electricity. A Rankine cycle with a back-pressure steam turbine was utilized to recover waste heat from the gas turbine, thereby generating electricity through the steam turbine. The bottom cycle is the Kalina cycle, which comprises another back-pressure turbine and utilizes ammonia–water mixture as working fluid. After driving the steam Rankine cycle, the flue gas from the gas turbine sequentially heats the ammonia–water mixture to produce power. A new operational strategy was presented to generate electricity during low insolation period without the backup of fossil fuel. In middle insolation periods, the air is heated by the solar field and then directly drives the steam Rankine cycle, bypassing the gas turbine. In low insolation periods, the heated air directly drive the Kalina cycle, bypassing the Brayton cycle and the steam Rankine cycle. The off-design performance was investigated and the irreversibility was disclosed with the aid of the energy-utilization diagram method. Thus, the proposed system can utilize low insolation to generate electricity. This study provides a possibility to improve the solar–electric efficiency. [Copyright &y& Elsevier]

A new solar tower thermal power system integrating the intercooled gas turbine top cycle and the Kalina bottoming cycle is proposed in the present paper. The thermodynamic performance of the proposed system is investigated, and the irreversibility of energy conversion is disclosed using the energy–utilization diagram method. On the top cycle of the proposed system, the compressed air after being intercooled is heated at 1000 °C or higher at the solar tower receiver and is used to drive the gas turbine to generate power. The ammonia–water mixture as the working substance of the bottom cycle recovers the waste heat from the gas turbine to generate power. A concise analytical formula of solar-to-electric efficiency of the proposed system is developed. As a result, the peak solar-to-electric efficiency of the proposed system is 27.5% at a gas turbine inlet temperature of 1000 °C under the designed solar direct normal irradiance of 800 W/m2. Compared with a conventional solar power tower plant, the proposed integrated system conserves approximately 69% of consumed water. The results obtained in the current study provide an approach to improve solar-to-electric efficiency and offer a potential to conserve water for solar thermal power plants in arid area. [Copyright &y& Elsevier]

Pt-Ni alloys have gained widespread attention due to the excellent properties and wide applications. However, the research on the structural, electronic and mechanical properties of disordered Pt 1-x Ni x solid solutions remain unclear and not enough. In this work, the first-principle calculation is used to investigate the structural, mechanical properties, and electronic structure of Pt 1-x Ni x solid solutions, which will be compared to the reference of Pt m Ni n intermetallic compounds. It is found that the atomic interaction of Pt 1-x Ni x solid solutions being weakened as the increase of Ni content, due to the stronger metallic characteristics. The Pt 1-x Ni x solid solutions show stable structure and high solid solubility. The ductile nature of Pt 1-x Ni x solid solutions is reduced, in compared to pure Pt. It is found the ductile nature of Pt 1-x Ni x solid solutions rebounds with a little degree in the range of Ni content (x) from 0.85 to 1.0. On the other hand, the stiffness is enhanced in the whole x range, in compared to pure Pt. The catalytic ability of Pt 1-x Ni x solid solutions is predicted to be enhanced in the range of 0 < x < 0.8. The investigation on electronic structure of Pt 1-x Ni x solid solutions indicates that the variation of above properties is related to the interaction behavior between Pt-5d states and Ni-3d states. By using the first-principle calculations, the underlying mechanism that causes the variation of properties is clarified in this work. This provides theoretical guidance for the application of Pt 1-x Ni x solid solution as structural materials and catalysts. • The disorder model of Pt 1-x Ni x solid solutions is constructed by SQS method. • The structure and properties of Pt 1-x Ni x solid solutions are compared to Pt m Ni n intermetallic compounds. • The atomic interaction of Pt 1-x Ni x solid solutions being weakened as the increase of Ni content. • The ductile nature of Pt 1-x Ni x solid solutions is reduced compared to pure Pt. • The underlying mechanism that causes the variation of properties is clarified. [ABSTRACT FROM AUTHOR]

System-level diagnosis has become an important diagnosis method for multiprocessor systems. Among all system-level diagnosis measures, diagnosability is relatively small. The conditional diagnosability constraint that each vertex has at least one good neighbor is relatively conservative when the dimension is far greater than 1, and g-good-neighbor conditional diagnosability does not consider this restriction on faulty vertices. Therefore, a thorough study of diagnosability under the condition that each vertex has at least g good neighbors is an appealing subject. Motivated by R g vertex connectivity, in this paper, we introduce a novel generalized system-level diagnosis measure named R g conditional diagnosability, which assumes that every processor has at least g good neighbors. The popular conditional diagnosability is a special case of R g conditional diagnosability when g = 1. Then, we determine that the R g conditional diagnosability of n -dimensional hypercube Q n under the Preparata Metze Chien (PMC) model is 2 2 g (n − 2 g) + 2 2 g − 1 − 1. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) porous architecture enables the high exploration of graphene excellent properties, i.e. large surface area and superior conductivity. Additionally, heteroatoms doping can improve the electrocatalytic activity of graphene by creating abundant defective/active sites. To combine the prominent advantages of 3D porous structure and heteroatoms doping, we reported the facile synthesis of 3D phosphorus (P)-doped graphene (3D-PG) and evaluated its potential application in electrochemical H 2 O 2 sensing. As an efficient metal-free electrocatalyst, 3D-PG modified electrode exhibited exceptional sensing performances for sensitive, selective and stable detection of H 2 O 2 , which was ascribed to the synergistic effects of 3D porous structure and P-doping in significantly enhancing the eletrocatalytic activity for H 2 O 2 reduction reaction. More importantly, the 3D-PG based sensor could be used for real-time tracking H 2 O 2 released from living HeLa cells, hence making 3D-PG a potential high-performance electrocatalyst for practical electrochemical sensing. [ABSTRACT FROM AUTHOR]

Heteroatom-doped graphene as highly efficient metal-free electrocatalyst is emerging as the most promising alternative to Pt-based electrocatalysts for hydrogen evolution reaction (HER). However, developing heteroatom-doped graphene with competitive HER activity remains a great challenge. Here, we reported an effective strategy to employ plasma-etching method to create more topological defects on S-doped graphene, and obtained plasma-etched, S-doped graphene exhibited a significantly enhanced HER activity with an overpotential of 178 mV at a current density of 10 mA cm −2 . It was proved that the synergetic coupling between S-doping and plasma-induced topological defects contributed to the excellent HER performance. We further showed that the combination of high S-doping level with thiophene-S-rich species and appropriate amount of topological defects could maximize the HER activity. The successful combination of plasma-assisted defect engineering and heteroatom-doping in this work may open up a new pathway for developing highly efficient graphene-based metal-free catalysts toward HER. [ABSTRACT FROM AUTHOR]

Exploring highly active, durable and low-cost catalysts toward hydrogen evolution reaction (HER) holds a key to clean energy technologies. Heteroatoms-doped graphene-based materials are emerging as the most promising metal-free HER catalysts, but their catalytic activity remains largely unexplored. Herein, by rationally engineering the macroscopic architecture of graphene and its chemical/defective structures, we developed a three-dimensional (3D), N-doped, plasma-etched graphene (3DNG-P) as a highly active metal-free HER catalyst. The obtained 3DNG-P combined the merits of freestanding 3D porous architecture, high-level N-doping and plasma-induced enriched defects, resulting in a highly enhanced HER activity with a low overpotential of 128 mV at 10 mA cm −2 in acidic medium. Furthermore, the 3DNG-P displayed a favorable HER activity and stability over a wide pH range. The present study thus provides a new methodology for the design of graphene-based metal-free catalysts with high HER performance. [ABSTRACT FROM AUTHOR]