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• A model of a Solid Oxide Fuel Cell-Inverted Brayton cycle hybrid system was established. • Direct integration of atmospheric SOFC and gas turbine is solved by atmospheric expansion. • Influence of steam injection rate and minimum cycle temperature on performance is explored. • The system performance demonstrates varied regulation laws under different pressure ratios. Enhancing the energy conversion efficiency of Solid Oxide Fuel Cells (SOFCs) hinges significantly on maximizing the recovery efficiency of high-temperature waste heat. The Inverted Brayton Cycle (IBC) emerges as a promising candidate for integration with ambient pressure SOFCs, thanks to its compatibility with atmospheric expansion dynamics. This study endeavors to model the Solid Oxide Fuel Cell-Inverted Brayton Cycle (SOFC-IBC) hybrid system, delving into the factors influencing IBC performance. Through meticulous simulation and analysis, we investigate the impacts of pressure ratio, minimum cycle temperature, and steam injection flow rate on system behavior. Additionally, we conduct a comprehensive examination of exergy destruction and efficiency implications. Our findings reveal a substantial enhancement in the IBC system's performance through pressure ratio incrementation or minimum cycle temperature reduction. Conversely, the steam injection flow rate exhibits divergent effects across different operational regions. The SOFC-IBC hybrid system demonstrates a remarkable potential to elevate SOFC exergy and thermal efficiency by 5.68 % and 11.68 %, respectively, thereby yielding a notable output power increase of 39.55 kW. Furthermore, optimizing pressure ratio or curbing steam injection flow rate proves beneficial for enhancing exergy efficiency. Crucially, the integration of the SOFC-IBC hybrid system offers a solution to the challenge posed by the pressure mismatch, which hinders the direct coupling of the gas turbine with the atmospheric SOFC. These insights underscore the applicability of IBC in atmospheric SOFC energy recovery systems, suggesting promising prospects for widespread adoption in energy optimization initiatives. [ABSTRACT FROM AUTHOR]

Growing evidence has demonstrated that gut microbiota could be developed as a therapeutic target due to its contribution to microglia activation in the pathological process of ischemic stroke. Acorus tatarinowii oils (AT oils), which is considered as the active fraction of a traditional Chinese herbal medicine Acorus tatarinowii , exerts various bioactivities and prebiotic effects. However, it remains unclear that the effect of AT oils on inflammatory response after ischemic stroke and whether its underlying mechanism is associated to gut microbiota and the intestinal barrier. In the current study, we aim to investigate the anti-microglial neuroinflammation mechanism of AT oils in a middle cerebral artery occlusion model of ischemic stroke. The compositions of AT oils were identified by GC-MS. Our results demonstrated that AT oils could effectively relieve cerebral infarction, inhibit neuronal apoptosis, degrade the release of pro-inflammatory factors (TNF- α , IL-17, IL-6 and IFN- γ), and mediate the polarization of microglia. Moreover, AT oils restored the composition and the balance of gut microbiota in stroke rats, and reduced abundance of opportunistic genera including Verrucomicrobia, Akkermansia and Tenericutes, as well as increased beneficial bacteria abundance such as Tenericutes and Prevotella_copri. To investigate the role of gut microbiota on AT oils against ischemic stroke, we conducted the fecal microbiota transplantation (FMT) experiments with gut microbiota consumption, which suggested that the depletion of gut microbiota took away the protective effect of AT oils, confirming the importance of gut microbiota in the protective effect of AT oils on ischemic stroke. FMT experiments have demonstrated that AT oils preserved the gut permeability and blood-brain barrier, as well as mediated the microglial phenotype under the intervention of gut microbiota. In summary, AT oils could efficaciously moderate neuronal damage and intervene microglial phenotype by reversing gut microbiota disorder in ischemic stroke rats. • Gut microbiota contributes to microglia activation in ischemic stroke. • SD rats were subjected to middle cerebral artery occlusion to induce cerebral ischemia. • Acorus tatarinowii oils could relieve cerebral infarction and mediate the polarization of microglia during reperfusion. • The mechanisms could be attributed to reversing gut microbiota disorder. [ABSTRACT FROM AUTHOR]

Abstract A novel cold and power cogeneration system is proposed in this paper. In the system, a "special" absorption refrigeration cycle is designed which is driven by liquefied natural gas (LNG) cryogenic energy with ammonia-water as working fluid. And this system contains two power processes, in which ammonia and natural gas are heated respectively by low-temperature heat source and then expanse in turbines. The thermodynamic performance of the cogeneration system is simulated and analyzed. The results show that the new cogeneration system demonstrations good thermal performance. The exergy efficiency of the system is as high as 36.1%. The coefficient of performance (COP) of the refrigeration cycle is 1.6 and the generating efficiency of power cycle reaches 38.8%. Sensitive analyses are performed to evaluate the effects of key parameters on the performance of the cogeneration system. Some values of the key parameters are recommended and the variations of the main thermodynamic characters are outlined. This new cogeneration system provides a new approach for the efficient utilization of LNG cold energy. [ABSTRACT FROM AUTHOR]

Highlights • Backpressure adjustable gas turbine combined-cycle is proposed. • Off-design characteristics with different operation strategies are analysed. • Load range with strategy keeping turbine inlet temperature constant is expanded. • Part-load efficiency is improved with a maximum increase of 0.52–1.76%. Abstract Nowadays, power demand and supply of the power grid fluctuate constantly for the increasing proportion of the renewable energy. Improving the operation performance of the gas turbine combined cycle (GTCC) power plant at part-load conditions is becoming a very critical problem. An innovative combined cycle solution, called backpressure adjustable gas turbine combined cycle (BAGTCC) with corresponding operation strategies, is proposed in this paper to improve off-design performance by adjusting turbine backpressure. The off-design calculation models of the combined cycle are built and their reliability is verified. The feasibility of this scheme is analyzed with the Mach number of the gas flow in turbine. Then, the part-load operation characteristics of the topping cycle, bottoming cycle and combined cycle of the GTCC and BAGTCC, operating with two different operation strategies respectively, are analyzed and compared. The simulation results show that, the proposed BAGTCC can broaden the load range, where turbine inlet temperature (TIT) maintains its design value, from 100–82.4% to 100–63.7%. The combined cycle efficiency has been improved significantly in that load range, up by 0–0.52 and 0–1.76 percentage points over the two conventional operation strategies respectively. Furthermore, this solution has the ability to adjust the power distribution of topping and bottoming cycle, which means that the heat-to-electric ratio can be adjusted when the bottoming cycle is involved in heating. The energy saving potential of BAGTCC can be increased by broadening the compressor flow adjustment range. In conclusion, backpressure regulating is an efficient method to improve the part-load efficiency of the GTCC. [ABSTRACT FROM AUTHOR]

• Abnormal retail investor attention and equity mispricing are positively correlated. • This effect is more pronounced in non-state-owned enterprises and enterprises with high equity incentives for executives and low audit quality. • Earnings management partially mediates the positive effect of abnormal retail investor attention on mispricing. This study examines the relationship between abnormal retail investor attention and equity mispricing in investors' target firms. Employing a sample of Chinese listed firms from 2013 to 2021, we find that abnormal retail investor attention, measured by Baidu search volume, has a significantly positive effect on such equity mispricing. Compared with underpricing, the positive relationship between abnormal retail investor attention and overpricing is more significant, with earnings management playing a mediating role in these effects. These findings also hold after controlling for potential endogenous effects. Further analyses show that the positive effect of abnormal retail investor attention on mispricing exists only for firms that are non-state-owned enterprises, have high executive equity incentives, and face lax external audits. [ABSTRACT FROM AUTHOR]

To undertake peak shaving tasks, gas turbine combined cycle (GTCC) units often deviate from the design operating point. In order to improve the off-design performance of GTCCs, a dual-recuperated gas turbine combined cycle (DRGTCC) system based on partial recuperation and compressor inlet air heating is proposed in this paper. The operating characteristics of the novel system using the proposed operation strategy are investigated, and the effects of pressure drop in recuperators and ambient temperature on system performance are discussed. The results indicate that, compared with the GTCC system, the DRGTCC system has higher turbine inlet temperature (TIT) and turbine expansion ratio at the same power output, and the performance has been improved especially at lower power outputs. When the inlet temperature of the compressor is increased from 0 °C to 45 °C, the air mass flowrate can be regulated between 46.0% and 100% of the design value. The combined cycle efficiency of the DRGTCC system is improved by 2.55 percentage points at 45.5% design combined cycle load. Moreover, the sensitivity analysis shows that the system performance decreases with the increase of the pressure drop in recuperators, and the ambient temperature affects the load regulation range and efficiency. • A dual-recuperated gas turbine combined cycle system is proposed. • The bottoming cycle can actively participate in load regulation. • Part-load characteristic prediction model considering the new operation strategy is designed. • Strategy combined multiple regulation methods achieves better part-load performance. • Sensitivity analyses of pressure drop and ambient temperature are carried out. [ABSTRACT FROM AUTHOR]

• A SOFC-IGT integrated distributed cogeneration system with zero CO 2 emission is proposed. • The operating parameters are optimized using multi-objective genetic algorithm. • The heat exchanger network synthesis is conducted. • The heat exchangers in the specific designs are designed and optimized. • The performances of the designs are verified and compared for specific application scenarios. Solid oxide fuel cell-gas turbine (SOFC-GT) hybrid system is an efficient and potential method for distributed energy supply. The system layout, component operating parameters, system-level heat integration, component selection and design, etc., determine the system performance. To further improve the performance and achieve zero CO 2 emissions, a ambient-pressure solid oxide fuel cell-inverted gas turbine (SOFC-IGT) hybrid system with CO 2 capture using oxy-fuel combustor was proposed. With the aid of partial-load component model and a multi-objective optimization method established, the heat exchanger network and heat exchanger physical structure were designed and optimized. The results show that, pursuing a higher gross electrical efficiency leads to a decline in heat output. The electrical efficiency can be improved by increasing the external reforming ratio while ensuring self-sufficiency in heat. The heat integration is critical to enhance system performance, and optimizing heat exchanger network can make full use of the heat of stack exhaust and reduce the demand for external cold utility. The heat exchanger structural design has a trade-off between the total heat-transfer coefficient and the pressure drop. The net electrical efficiency of the three special solutions can reach 53.9 %, 65.7 %, and 65.8 %, respectively. The design of the maximum heat point (MHP) scheme can be considered when pursuing lower cost, and the design of the maximum power point (MPP) scheme can be employed for higher performance. [ABSTRACT FROM AUTHOR]

Highlights: [•] A novel open-die warm extrusion process of spline shaft with 42CrMo steel is proposed. [•] 42CrMo steel’s material characteristic during the warm forming process is studied. [•] An optimum die angle of entrance section on extrusion die is established. [•] An optimum warm forming temperature during the warm extrusion process is established. [•] The tooth divided flow method is employed to improve the warm extrusion process. [Copyright &y& Elsevier]

A novel combined cooling and power (CCP) system utilizing liquefied natural gas (LNG) cryogenic energy and low-temperature waste heat was presented. The proposed system consists of two subsystems, absorption refrigeration/power cycle (ARP) subsystem and LNG refrigeration/power cycle (LRP) subsystem. The Rankine cycle and absorption refrigeration cycle were connected in series to form the ARP and they showed mutual enhancement in the integration. The operating performance of the system was calculated and analyzed. And the effects of generator pressure and circulation ratio on the performance were analyzed. Furthermore, a typical application case, in which the proposed system is integrated into the gas-steam combined cycle system as an LNG pre-processing and power enhancement unit, had been studied. The results showed that the net power generation efficiency, comprehensive energy utilization ratio, and exergy efficiency of the proposed CCP system reached 32.70%, 81.63%, and 35.14%, respectively. The feasibility and performance of the integrated system with combined cycle gas turbine were proved. And suggestions for the parameter design were presented. • A cogeneration system is proposed to utilize LNG cryogenic energy and waste heat. • Rankine cycle and absorption refrigeration cycle are combined in series. • Net power generation efficiency and exergy efficiency reach 32.70% and 35.14%. • Suggestions for system design are presented. • The integration with combined cycle gas turbine greatly improves performance. [ABSTRACT FROM AUTHOR]

• A combined cycle system with intermediate recuperated gas turbine is proposed. • The load range of constant turbine inlet temperature operating mode is extended. • Gas turbine and combined cycle part-load efficiency is improved by 2.15% and 1.04%. • Effects of pressure drop and minimum recuperative flow on performance are analyzed. In order to improve the performance of the combined cycle gas turbine (CCGT) under off-design conditions, an intermediate recuperated combined cycle gas turbine (IRCCGT) system was proposed, which was designed to suppress turbine inlet temperature (TIT) from decreasing as the load drops. In this system, a heat exchanger is installed between the third and fourth turbine stages, wherein a portion of the exhaust from the third turbine stage was used to heat the compressed air. In addition, the system-based operation strategy (maximizing the load range that employs constant TIT operation mode) was also analyzed. The results indicate that the TIT can be maintained at the design value until the gas turbine power load is reduced to 49% of the design value. When the inlet guide vane (IGV) angle reached the minimum value, the IRCCGT system increased gas turbine efficiency and combined cycle electrical efficiency by 4.7 and 3.1 percentage points. At the same gas turbine (GT) load, the maximum gains of GT efficiency and combined cycle efficiency were 2.15 and 1.04 percentage points, respectively. The pressure drops in the recuperator had a great impact on system performance, while the minimum recuperative mass flow rate had little effect. Overall, the proposed IRCCGT system can reduce the slope of the efficiency and load curve and improve the operating performance of the system under off-design conditions. [ABSTRACT FROM AUTHOR]

A partially recuperative gas turbine combined cycle (GTCC pr ) is proposed in this paper to improve the off-design performance of power plants. The performance coupling with a new operation strategy is also analyzed. In the proposed GTCC pr , the gas flow at the outlet of the turbine is divided into two streams, and only a part of exhaust gas from the turbine is used to preheat the outlet air of the compressor. Exhaust gas streams from the recuperator are mixed with flue from the second reheater at the inlet of the first reheater to achieve similar temperature level. Specifically, the fraction of exhaust gas that preheats air can be changed to adjust the load of the combined cycle. The PG9351FA gas turbine unit is selected as the reference unit for comparison. Then, the design/off-design characteristics of the two cycles are compared and analyzed with the same turbine initial temperature. Results indicate that the partially recuperative GTCC pr running with the new operation has better off-design performances than the reference unit with approximately 1.7% maximum difference of efficiency. At the design point, the exhaust gas used for partial recuperation only accounts for 10% of the total mass, and the effect of recuperation is not evident. Therefore, the two cycles possess nearly similar output and efficiency. The efficiency of partially recuperative GTCC pr is nearly unchanged with the increasing recuperative mass fraction, which changes its specific power to adjust the load. At low loads, with decreasing turbine exhaust gas temperature, the efficiency improvement also decreases due to the partial recuperation. A comprehensive comparison with the reference unit revealed that GTCC pr with the proposed “recuperation adjustment” method can maintain a higher off-design efficiency and slightly lower design power output compared with the conventional cycle. Specific power adjustment of recuperation is one of the efficient methods for load adjustment, and GTCC pr is one of the best options. [ABSTRACT FROM AUTHOR]

This study investigates a novel supercritical carbon dioxide Brayton cycle with a bleeding anabranch used in coal-fired power plants. For the proper utilization of the medium-low temperature heat in the boiler, the coupling between the air-preheater and the cycle is concentrated. After analyzing the distribution of heat duty in the boiler, the flow diagram of the Brayton cycle is design. Subsequently, the influences of maximal temperature/pressure, pinch temperature difference, component pressure drop, and preheated air temperature on the cycle efficiency are studied. Results show that the proposed cycle coupled with a coal-fired power plant can achieve 52.33% gross cycle efficiency and 49.5% net low heat value efficiency with 296 bar/650 °C. A further increment of 1% pt. in gross cycle efficiency can be achieved with the decrement of 5 K pinch temperature difference or 0.7 bar pressure loss in the recuperators. The simulation indicates that an increment of 2.14% pt. in gross cycle efficiency can be further achieved with 370 bar/700 °C. Besides, the parameter of the bleeding anabranch do not affect the cycle performance. In conclusion, this study proposes a promising novel supercritical carbon dioxide cycle coupled with coal-fired power plants. [ABSTRACT FROM AUTHOR]

A novel method for the combined cycle retrofitted with compressor inlet air heating (HEAT) process is proposed in this work for part load performance improvement. The performance of the new cycle is researched with two regulations with HEAT and compared with another two strategies with compressor inlet guide vane (IGV). For the novel method, the compressor inlet air is preheated by part of the exhaust flue gas from the heat recovery steam generator. Moreover, comparation result indicates that the novel strategy with HEAT to maintain design turbine inlet temperature (T3) and then to keep turbine exhaust temperature (T4) at its maximum value (HEAT-T3-T4) is suggested for load arrangement. If being compared with the cycle using IGV control to maintain design T3 then keep extreme T4 (IGV-T3-T4), a maximum combined cycle efficiency increment as 1.7% pt. could be obtained by the cycle with HEAT-T3-T4. Both energy analysis and exergy analysis are given in this paper. The simulation results indicate that higher compressor outlet temperature (T2) decreases the extra exergy destruction during combustion, so that the performance of the cycle with HEAT is improved. Meanwhile the specific work of each cycle has also been presented. Furthermore the pressure loss affection of the compressor inlet air heat exchanger on the combined cycle performance is investigated in range of 0%–5%. Each 1% pressure loss is calculated to decrease 1.4% on the design power output, and 0.25% pt. on the combined cycle efficiency, which will weaken the performance improvement. To summarize, this paper proposes a novel method for the combined cycle power output adjustment to obviously improve its part load efficiency. This innovative solution has never been suggested before and it could be combined with other methods for better result. • Compressor inlet air heating is purposed for cycle load regulation. • Waste energy can be recovered and exergy loss can be partly reduced by the method. • New method is compared with IGV control by two pairs of operation strategies. • 1.1% pt. - 1.7% pt. efficiency increment is achieved at cycle load 45%–100%. [ABSTRACT FROM AUTHOR]

Highlights • Transcriptional induction of Bim is observed in nigral dopaminergic neurons by in situ detection after MPTP intoxication. • Bim upregulation in the dopaminergic neurons contributes to MPTP-induced parkinsonian neurodegeneration. • c-Jun activates Bim to promote MPTP-induced nigral dopaminergic neurodegeneration. Abstract Parkinson's disease (PD) is a common neurodegenerative disease that is characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc). The proapoptotic BH3-only protein Bim has been reported to be involved in dopaminergic neurodegeneration of experimental PD. However, an in situ expression profile of Bim in PD has not been performed, and the cell types of which Bim accounts for PD pathogenesis is unclear. Here, we report with in situ observations that Bim is transcriptionally induced in the dopaminergic neurons of the SNpc in 1-methyl-4-pheny-1,2,3,6-tetrahydropyridine (MPTP)-treated mice. To investigate the precise role of Bim in the dopaminergic neurons in parkinsonian neuronal death, we obtained dopaminergic neuron-specific Bim null (Bim△Dat) mice. Bim△Dat mice are shown to be resistant to MPTP-induced neurotoxicity, confirming that the induction of Bim in dopaminergic neurons is responsible for parkinsonian neurodegeneration. Furthermore, we demonstrated with dopaminergic neuron-specific c- Jun knockout (c-Jun△Dat) that the transcriptional upregulation of Bim of nigral dopaminergic neurons was c-Jun-dependent and further validated the detrimental role of c-Jun in dopaminergic neurodegeneration. Together, these data specify that c-Jun-mediated Bim upregulation in nigral dopaminergic neurons contributes to parkinsonian neurodegeneration. [ABSTRACT FROM AUTHOR]

Agledulines A-K, eleven previously undescribed limonoids, including eight biogenic A/D-rings- seco limonoid analogs (agledulines A-H), one D-ring- seco limonoid (agleduline I) and two A-ring- seco limonoids with a rare Δ4,28 moiety (agledulines J-K), together with twelve reported limonoids, were isolated from the fruits of Aglaia edulis. Their structures were determined by NMR data, HRESIMS, X-ray diffraction, ECD spectra and the CD exciton chirality method. Observably, the absolute configurations of agleduline A, agleduline C and nymania 2 were unambiguously elucidated by single-crystal X-ray diffraction analyses. The biological evaluation showed that agleduline C exhibited significant cytotoxic activities with IC 50 values of 10.05 μ M, and 11 α -acetoxygedunin showed notable anti-inflammatory activity (IC 50 : 4.70 μ M). In addition, agleduline I and 11 α -acetoxygedunin reversed the multidrug resistance with IC 50 values of 5.05 and 1.49 μ M (RI: 4.64 and 15.77) in the MCF-7/Dox cells. [Display omitted] • Eleven previously undescribed limonoids were isolated from the Aglaia edulis. • Their absolute configurations were elucidated by X-ray crystallography and ECD. • Eight limonoids exhibited diverse bioactivities. [ABSTRACT FROM AUTHOR]

• A method for Sarcandra glabra callus induction and proliferation was established. • Two sesquiterpenoids, chloranthalactone A and atractylenolide II, could be produced in S. glabra callus. • The production of chloranthalactone A and atractylenolide II was enhanced by abiotic stress and elicitor treatment. Sarcandra glabra , a traditional Chinese medicine and herbal tea, has benefits from treating inflammation and fractures to curing cancer. The anti-inflammatory properties of sesquiterpenoids (chloranthalactone A, CTA; atractylenolide II, AT-II) have made S. glabra to a great potential for research and development. Here this study developed S. glabra callus culture to circumvent particular needs of the plant growing seasons and Hardiness zone, with the goal being able to produce sesquiterpenoids in vitro. The half strength Murashige and Skoog (1/2MS) medium supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D, 2.0 mg/L) and 6-benzylaminopurine (6-BA, 1.0 mg/L) was effective for callus induction. The 1/2MS medium supplemented with 2,4-D (2.0 mg/L) and 6-BA (0.5 mg/L) was superior for callus proliferation. The callus was friable, yellowish and rapidly grown without tissue differentiation. Moreover, high performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS) analysis indicated that the contents of CTA and AT-Ⅱ in multiple subculture S. glabra callus were 3.72 ± 0.51 mg/g and 0.50 ± 0.12 mg/g in fresh weight (FW), respectively. Using abiotic stresses and elicitors, production of CTA (by ultraviolet-B radiation for 48 h) and AT-II (by methyl jasmonate, 100 μmol/L) was enhanced by 2.3-fold. In conclusion, this work not only established the S. glabra callus culture for in vitro production of CTA and AT-II, but also provided the foundation for further development and utilization of S. glabra. [ABSTRACT FROM AUTHOR]