Key CO_(2)capture technology of pure oxygen exhaust gas combustion for syngas-fueled high-temperature fuel cells

Integrated gasification fuel cells(IGFCs)integrating high-temperature solid oxide fuel cell technology with CO_(2)capture processes represents highly-efficient power systems with negligible CO_(2)emissions.Flame burning with pure oxygen is an ideal method for fuel cell exhaust gas treatment,and this report describes experimental and numerical studies regarding an oxy-combustor for treating the exhaust gas of a 10 kW IGFC system anode.The applied simulation method was verified based on experiments,and the key performance indices of the combustor were studied under various conditions.It was determined that 315 K was the ideal condensation temperature to obtain flame stability.Under these pure oxygen flame burning conditions,CO was almost completely converted,and the dry mole fraction of CO_(2)after burning was C 0.958 when there was up to 5%excess O_(2).Overall,5%excess O_(2)was recommended to maximize CO_(2)capture and promote other environmental considerations.Additionally,the optimal tangential fuel jet angle to control the liner temperature was approximately 25°.The total fuel utilization had to be high enough to maintain the oxygen flame temperature of the anode exhaust gas below 1800 K to ensure that the system was environmentally friendly.The results presented herein have great value for designing IGFCs coupled with CO_(2)capture systems.

Anti-inflammatory effects of amarogentin on 2,4-dinitrochlorobenzene-induced atopic dermatitis-like mice and in HaCat cells

Background:Amarogentin(AMA)is a secoiridoid glycoside extracted from Swertia and Gentiana roots and exhibits many biological effects such as antioxidative,antiinflammatory,and antitumor activities.Atopic dermatitis(AD)is a chronic inflammatory skin disease caused by disorders in the regulation of multiple inflammatory cytokines.No effective cure has been found for AD now.Methods:We constructed the HaCat and splenocyte model and tested the inhibitory effect of AMA on IL-4,IL-6,and IL-13 secretions using enzyme-linked immunosorbent assay(ELISA).The AD mouse model was constructed and treated with AMA,the severity of skin lesions was observed,epidermal tissue was collected,and epidermal thickness and mast cell infiltration were observed using hematoxylin and eosin and toluidine blue staining,respectively.The expression of kallikrein-related peptidase 7(KLK7)and filaggrin(FLG)was detected using immunostaining and Western blot analysis.The mRNA expression of KLK7 and FLG was detected using quantitative polymerase chain reaction(qPCR).Blood immunoglobulin E(IgE)secretion was detected.Results:AMA inhibited IL-6 secreted by tumor necrosis factor(TNF)-α-induced HaCaT cells and reduced IL-4 and IL-13 secreted by phytohemagglutinin(PHA)-induced primary cells in the mice spleen.It was found that the treatment of AMA with 2,4-din itrochlorobenzene-induced AD-like mice could promote the recovery of dermatitis,reduce the score of dermatitis severity and the scratching frequency,treat the skin lesions,reduce the epidermal thickness,decrease the infiltration of mast cells,reduce the IgE level in serum,decrease the expression levels of AD-related cytokines,increase protein and mRNA expression of FLG,and reduce the protein and mRNA expression of KLK7 in the skin tissues of AD-like mice.Conclusion:In conclusion,AMA inhibits inflammatory response at the cellular level,and AMA reduces the validation response of specific dermatitis mice,relieves pruritus,and repairs the damaged skin barrier.

Electrical characteristics of new three-phase traction power supply system for rail transit

A novel three-phase traction power supply system is proposed to eliminate the adverse effects caused by electric phase separation in catenary and accomplish a unifying manner of traction power supply for rail transit.With the application of two-stage three-phase continuous power supply structure,the electrical characteristics exhibit new features differing from the existing traction system.In this work,the principle for voltage levels determining two-stage network is dissected in accordance with the requirements of traction network and electric locomotive.The equivalent model of three-phase traction system is built for deducing the formula of current distribution and voltage losses.Based on the chain network model of the traction network,a simulation model is established to analyze the electrical characteristics such as traction current distribution,voltage losses,system equivalent impedance,voltage distribution,voltage unbalance and regenerative energy utilization.In a few words,quite a lot traction current of about 99%is undertaken by long-section cable network.The proportion of system voltage losses is small attributed to the two-stage three-phase power supply structure,and the voltage unbal-ance caused by impedance asymmetry of traction network is less than 1‰.In addition,the utilization rate of regenerative energy for locomotive achieves a significant promotion of over 97%.

Investigation of electron cyclotron wave absorption and current drive in CFETR hybrid scenario plasmas

The investigation of electron cyclotron(EC)wave absorption and current drive has been performed for the China Fusion Engineering Test Reactor(CFETR)hybrid scenarios using the TORAY code.To achieve the physics goal of the EC system in CFETR,a total of four wave frequency values and nine locations of launching antennas have been considered,and the injection poloidal and toroidal angles have been scanned systematically.The electron cyclotron current drive(ECCD)efficiency of the 170 GHz EC system is quite low due to the wave-particle interactions being located at the low-field side.To optimize the ECCD efficiency,the wave frequency is increased up to 221–250 GHz,which leads to the power being deposited at the high-field side.The off-axis ECCD efficiency can be significantly enhanced by launching EC waves from the top window and injecting them towards the high-field side.The optimized ECCD efficiency atρ=0.32 and atρ=0.4 is 2.9 and 2.2 times that of 170 GHz,respectively.

Status of an MWth integrated gasification fuel cell powergeneration system in China

Abstract Here,we provide a status update of an integrated gasification fuel cell(IGFC)power-generation system being developed at the National Institute of Clean-and-Low-Carbon in China at the megawatt thermal(MWth)scale.This system is designed to use coal as fuel to produce syngas as a first step,similar to that employed for the integrated gasification combined cycle.Subsequently,the solid-oxide fuel-cell(SOFC)system is used to convert chemical energy to electricity directly through an electrochemical reaction without combustion.This system leads to higher efficiency as compared with that from a traditional coal-fired power plant.The unreacted fuel in the SOFC system is transported to an oxygencombustor to be converted to steam and carbon dioxide(CO_(2)).Through a heat-recovery system,the steam is condensed and removed,and CO_(2) is enriched and captured for sequestration or utilization.Comprehensive economic analyses for a typical IGFC system was performed and the results were compared with those for a supercritical pulverized coal-fired power plant.The SOFC stacks selected for IGFC development were tested and qualified under hydrogen and simulated coal syngas fuel.Experimental results using SOFC stacks and thermodynamic analyses indicated that the control of hydrogen/CO ratio of syngas and steam/CO ratio is important to avoid carbon deposition with the fuel pipe.A 20-kW SOFC unit is under development with design power output of 20 kW and DC efficiency of 50.41%.A 100 kW-level subsystem will consist of 6920-kW power-generation units,and the MWth IGFC system will consist of 59100 kWlevel subsystems.

Performance test of a 5 kW solid oxide fuel cell system under high fuel utilization with industrial fuel gas feeding

As the demand for green energy with high efficiency and low carbon dioxide(CO2)emissions has increased,solid oxide fuel cells(SOFCs)have been intensively developed in recent years.Integrated gasification fuel cells(IGFCs)in particular show potential for large-scale power generation to further increase system efficiency.Thus,for commercial application of IGFCs,it is important to design reliable multi-stacks for large systems that show long-term stability and practical fuel gas for application to industrial equipment.In this work,a test rig(of a 5 kW SOFC system,with syngas from industrial gasifiers as fuel)was fabricated and subjected to long-term tests under high fuel utilization to investigate its performance.The maximum steady output power of the system was 5700 W using hydrogen and 5660 W using syngas and the maximum steady electrical efficiency was 61.24%while the fuel utilization efficiency was 89.25%.The test lasted for more than 500 h as the fuel utilization efficiency was larger than 83%.The performances of each stack tower were almost identical at both the initial stage and after long-term operation.After 500 h operation,the performances of the stack towers decreased only slightly under lower current and showed almost no change under high current.These results demonstrate the reliability of the multi-stack design and the prospect of this SOFC power-generation system for further enlarging its application in a MWth demonstration.

Optimization of X-mode electron cyclotron current drive in high-electron-temperature plasma in the EAST tokamak

A discharge with electron temperature up to 14 keV has been achieved in EAST.Analysis of the electron cyclotron current drive(ECCD)efficiency at high electron temperature under EAST parameters is presented using C3PO/LUKE code.Simulation results show that the ECCD efficiency of X-mode increases with central electron temperature up to 10 keV and then starts to decrease above 10 keV,at a specific magnetic field and toroidal angle.The efficiency degradation is due to the presence of the third harmonic extraordinary(X3)downshifted absorption at the low field side(LFS);even the cold resonance of X3 mode is located outside the plasma.As the electron temperature increases from 5 to 20 ke V,the X3 absorption increases from 0.9%to 96.4%.The trapping electron effect at the LFS produces a reverse Ohkawa current.The competition between the Fisch–Boozer current drive and the Ohkawa current drive results in a decrease in ECCD efficiency.ECCD efficiency optimization is achieved through two methods.One is to increase the toroidal angle,leading to X2 mode predominating again over X3 mode and the electron resonance domain of X2 mode moving far from the trapped/passing boundary.The second one is to increase the magnetic field to move away the X3 resonance layer from the plasma,hence less EC power absorbed by X3 mode.

方解石和方镁石混合矿物除磷性能及机理探究

以方解石和方镁石为原料按质量比4:1混合制得CPMM,考察了固液比、反应时间、初始浓度对其除磷能力的影响,并利用红外光谱对吸附产物进行表征分析。结果表明:CPMM处理20mg/L的含磷废水的最适固液比为1g/L,CPMM对磷酸根的去除符合伪二级动力学方程,等温吸附曲线符合Langmuir模型,25℃的饱和吸附容量为45.41mg/g.CPMM去除水中磷的机理是形成轻基磷灰石的表面沉淀。

植物恢复工程对湖泊甲烷循环系统影响的研究

受污染的水体经过疏通底质、控制纳污、引配水等一系列工程措施后初期,生态系统较敏感,水体自净能力较差。通过植物恢复工程,能够逐渐恢复并建立稳定增强的植物-微生物生态系统,提高水体的自净能力,从根本上净化水体。同时,经人工优化水生植物的种植,可以改变湖泊中以产甲烷菌介导的湿地甲烷循环系统,有效减少湖泊沉积物中甲烷排放,对水污染及大气污染同时具有良好的生态治理效益。

Electric-Induced Cycloelimination for Simulating Structural Plasticity in Organic Nociceptors

Continuous lifelong acquisition,updating,and finetuning of knowledge and skills is of crucial significance for the survival of humans.However,current neuromorphic devices exhibit obvious catastrophic forgetting when restimulated by new information.This remains a challenge for neuromorphic devices and artificial intelligence to achieve continuous learning.Herein,we propose an electric-induced cycloelimination strategy to realize an organic transistor nociceptor that can simulate synaptic and structural plasticity.The system benefits from the ring-opening characteristics of cross-linked poly(vinyl cinnamate)under a strong pulse voltage,during which new energy-level trap states are formed.The prepared organic transistor nociceptors exhibit both structural and synaptic plasticity.They simulate the characteristics of human nociceptors,including threshold,relaxation,sensitization,and maladaptation behavior.For the first time,we have simulated and explored the structural plasticity behavior in organisms based on electronic devices.More remarkably,the transistor nociceptors realize the reinput of information without forgetting the initial informa tion.The strategy developed for the preparation of organic transistor nociceptors provides insights for addressing the catastrophic forgetting in the lifelong learning of intelligent neuromorphic devices.

Phytolith records of the climate change since the past 15000 years in the middle reach of the Yangtze River in China

Based on 14C dating and core sediments survey, phytolith records are employed to reconstruct paleovegetation and paleoclimate in the Jianghan Plain in the middle reach of the Yangtze River. Phytoliths identified are assigned into 21 well-described morphotypes and divided into four groups （Poaceae, fern, coniferous and broad-leaved）. The phytolith assemblages together with warmth index （Iw） are divided into 18 ecological zones, which reflect a complete vegetation history related to climate change in the middle reach of the Yangtze River during the past 15000 years. On the basis of the correlation ofphytolith records with the paleoclimatic indicators from stalagmite, peatland, North Atlantic deep-sea sediments, Loess Plateau of Central China, and Arabic Sea sediments, eight climatic phases are identified included Last Glacial Maximum （LGM） （20- 14.8 cal kaBP）, Last Deglaciation （LDG） （14.8-11.9 cal kaBP）, low-temperature phase in the Early Holocene （11.9-8 cal kaBP）, Holocene Opti- mum （8-4.9cal kaBP）, Holocene Katathermal （4.9- 1.1 cal kaBP）, Medieval Warmth Period （MWP） （1.1- 0.7 cal kaBP）, Little Ice Age （LIA） （0.7-0.15 cal kaBP）, and Modem Warming （0.15 cal kaBP-present）. Climatic events such as Bolling-Allerod warm intervals, Older Dryas, Inter-Allerod Cold Period, and Younger Dryas, and eight Holocene Bond events （B1-8） have been identified since the LDG. Our results demonstrate that the evolution of the climate in the research area has a strong link with the Indian Summer Monsoon （SW Monsoon）, Asian Summer Monsoon （SE Monsoon）, and Holocene events in North Atlantic simultaneously, which might indicate that solar variability affects the Earth surface climate system at the centennial and millennial scales.

Low temperature growth of clean single layer hexagonal boron nitride flakes and film for graphenebased field-effect transistors

Two dimensional (2D) materials have attracted intense attention owing to their unique physical and chemical properties and the realization of artificial structure and functionality [1]. Insulating hexagonal boron nitride (h-BN), a one-atom thick crystal with a large bandgap (6 eV)[2], superior chemical and thermal stability, and a higher thermal conductivity, is known as “white graphene” due to their similar structure.a lattice mismatch of only 1.6%.

An isoindigo-bithiazole-based acceptor-acceptor copolymer for balanced ambipolar organic thin-film transistors

Balanced carrier transport is observed in acceptor-acceptor （A-A＇） type polymer for ambipolar organic thin-film transistors （OTFTs）. It is found that the incorporation of two electron-accepting moieties （BTz and IIG） into a polymer main chain to form A-A＇ polymer PIIG-BTz could lower highest occupied molecular orbital （HOMO） and lowest unoccupied molecular orbital （LUMO） levels and facilitate good molecular stacking of the polymer. Ambipolar transistor behaviour for PIIG-BTz, with the balanced hole and electron mobilities of 0.030 and 0.022 cm2 V 1 s-i was observed in OTFT devices, respectively. The study in this work reveals that the utilization of acceptor-acceptor （A-A＇） structure in polymer main chain can be a feasible strategy to develop ambipolar polymer semiconductors.

Organic photodetectors based on supramolecular nanostructures

Self‐assembly of semiconducting(macro)molecules enables the development of materials with tailored‐made properties which could be used as active components for optoelectronics applications.Supramolecular nanostructures combine the merits of soft matter and crystalline materials:They are flexible yet highly crystalline,and they can be processed with low‐cost solution methods.Photodetectors are devices capable to convert a light input into an electrical signal.To achieve high photoresponse,the photogenerated charge carriers should be transported efficiently through the self‐assembled nanostructures to reach the electrodes;this can be guaranteed via optimalπ–electron overlapping between adjacent conjugated molecules.Moreover,because of the high surface‐to‐bulk ratio,supramolecular nanostructures are prone to enhance exciton dissociation.These qualities make supramolecular nanostructures perfect platforms for photoelectric conversion.This review highlights the most enlightening recent strategies developed for the fabrication of high‐performance photodetectors based on supramolecular nanostructures.We introduce the key figure‐of‐merit parameters and working mechanisms of organic photodetectors based on single components and p–n heterojunctions.In particular,we describe new methods to devise unprecedented planar and vertical devices to ultimately realize highly integrated and flexible photodetectors.The incorporation of ordered mesoscopic supramolecular nanostructures into macroscopic optoelectronic devices will offer great promise for the next generation of multifunctional and multiresponsive devices.

天然黑钨矿应用于光催化降解土霉素

采用天然半导体矿物黑钨矿作为光催化剂用于降解废水中的土霉素。研究了固液比、光照强度、初始浓度对土霉素降解的影响,并解析了降解机理和路径。结果表明,可见光下黑钨矿对土霉素具有较好的降解效果,在浓度为15 mg/L、pH=4.5、固液比为1.0 g/L、光照强度60 W的条件下,120 min时土霉素的去除效率可以达到94.3%,黑钨矿对于土霉素的去除速率符合一级动力学反应规律。淬灭实验和电子顺磁光谱结果表明羟基自由基(·OH)和超氧阴离子自由基(·O_(2)^(-))是导致土霉素降解的主要活性氧化物种,分别在120 min时降解了20.4%和10%的土霉素。液相色谱-质谱联用显示土霉素经过羟基化、去甲基化、和脱羰化降解为中间产物,使其化学毒性下降,有利于工艺在抗生素处理中的工业化应用。

Phosphorylation of PHF2 by AMPK releases the repressive H3K9me2 and inhibits cancer metastasis

Epithelial to mesenchymal transition (EMT) plays a crucial role in cancer metastasis, accompanied with vast epigenetic changes.AMP-activated protein kinase (AMPK), a cellular energy sensor, plays regulatory roles in multiple biological processes. Although afew studies have shed light on AMPK regulating cancer metastasis, the inside epigenetic mechanisms remain unknown. Herein weshow that AMPK activation by metformin relieves the repressive H3K9me2-mediated silencing of epithelial genes (e.g., CDH1)during EMT processes and inhibits lung cancer metastasis. PHF2, a H3K9me2 demethylase, was identified to interact with AMPKα2.Genetic deletion of PHF2 aggravates lung cancer metastasis and abolishes the H3K9me2 downregulation and anti-metastasis effectof metformin. Mechanistically, AMPK phosphorylates PHF2 at S655 site, enhancing PHF2 demethylation activity and triggering thetranscription of CDH1. Furthermore, the PHF2-S655E mutant that mimics AMPK-mediated phosphorylation status further reducesH3K9me2 and suppresses lung cancer metastasis, while PHF2-S655A mutant presents opposite phenotype and reverses the antimetastasiseffect of metformin. PHF2-S655 phosphorylation strikingly reduces in lung cancer patients and the higherphosphorylation level predicts better survival. Altogether, we reveal the mechanism of AMPK inhibiting lung cancer metastasis viaPHF2 mediated H3K9me2 demethylation, thereby promoting the clinical application of metformin and highlighting PHF2 as thepotential epigenetic target in cancer metastasis.

Time series analysis model for forecasting unsteady electric load in buildings

Accurate and reliable load forecasting is crucial for ensuring the security and stability of the power grid.This paper proposes a combined prediction method based on Empirical Wavelet Transform(EWT)and Autoformer time series prediction model for the non-stationary and non-linear time series of electric load.The original sequence is first decomposed by EWT to obtain a set of stable subsequences,and then the Autoformer time series prediction model is used to predict each subsequence.Finally,the prediction results of each subsequence are combined to obtain the final prediction results.The proposed EWT-Autoformer prediction model is applied to an electric load example,and the experimental results are compared with the Recurrent Neural Network(RNN)method,Long Short-Term Memory(LSTM)method,and Informer method under the same conditions.The experimental results indicate that compared to LSTM,the method proposed in the paper has an R2 improvement of 9–20 percentage points,an improvement of 6–8 percentage points compared to RNN,an improvement of 3–7 percentage points compared to Informer,and an improvement of 2–3 percentage points compared to Autoformer.In addition,the RMSE and MAE are also significantly lower than other models.