Effect of carbon material and surfactant on ink property and resulting surface cracks of fuel-cell microporous layers

Ensuring the consistency of electrode structure in proton-exchange-membrane fuel cells is highly desired yet challenging because of wide-existing and unguided cracks in the microporous layer(MPL). The first thing is to evaluate the homogeneity of MPL with cracks quantitatively. This paper proposes the homogeneity index of a full-scale MPL with an area of 50 cm~2, which is yet to be reported in the literature to our knowledge. Besides, the effects of the carbon material and surfactant on the ink and resulting MPL structure have been studied. The ink with a high network development degree produces an MPL with low crack density, but the ink with high PDI produces an MPL with low crack homogeneity. The polarity of the surfactant and the non-polarity of polytetrafluoroethylene(PTFE) are not mutually soluble,resulting in the heterogeneous PTFE distribution. The findings of this study provide guidelines for MPL fabrication.

Exploring influence of MgO/CaO on crystallization characteristics to understand fluidity of synthetic coal slags

The crystallization has significant influence on fluidity of slag and slag discharge of entrained-flow-bed(EFB) gasifier. The crystallization characteristics and fluidity of five synthetic slags with different MgO/CaO ratios prepared on the basis of the range of oxide contents of Zhundong coal ash were investigated in this study. The results show that with the MgO/CaO ratio increase, the initial crystallization temperature increases, and the main temperature range of crystallization ratio growth moves to higher temperature range gradually which causes Tp25(Tp25is the temperature corresponding to the viscosity of 25 Pa·s)to increase. Mg-rich crystals are formed preferentially than Ca-rich crystals when adding the same amount of MgO and CaO during cooling. The effective slagging operating temperature range decrease from 217 ℃ for the slag with a 0:4 MgO/CaO ratio to 44 ℃ for the slag with a 4:0 MgO/CaO ratio with the MgO/CaO ratio increase. The slags with 2:2 and 1:3 MgO/CaO ratios show similar effective slagging operating temperature range, Tp25and the temperature corresponding to the viscosity of 2 Pa·s.However, compared with the slag with a 1:3 MgO/CaO ratio, the crystallization ratio and rate of slag with a 2:2 MgO/CaO ratio are lower within lower temperature range(1300–1200 ℃), causing its lower critical viscosity temperature and wider actual operating temperature range. Of the five slags, the widest effective slagging operating temperature range and the lowest Tp25of the slag with a 0:4 MgO/CaO ratio due to its low crystallization ratio, and wider actual operating temperature range of the slag with a 2:2 MgO/CaO ratio make the two slags suitable for slag discharge of EFB gasifier.

Consumer behavior patterns of carbon neutral label using the unified theory of acceptance and use of technology

China has paid considerable attention to developing and implementing a carbon labeling system in response to increasing environmental issues such as global warming.This paper aims to provide a theoretical basis for formulating and implementing a carbon labeling system in China through a study of consumer acceptance behavior and its influencing factors.This paper constructed an extended model of consumers’acceptance behavior of carbon neutral labels based on the theories and methods of Unified Theory of Acceptance and Use of Technology(UTAUT)and analyzed the effects of five factors(carbon label cognition,performance expectancy,effort expectancy,social influence,and facilitating factors)on consumer carbon neutral label acceptance and adoption.The structural equation model analysis revealed that carbon label cognition,performance expectancy,social influence,and facilitating factors significantly,and positively impact consumers’acceptance of carbon neutral labels.Moreover,carbon label cognition,performance expectancy,and facilitating factors significantly,and positively affect consumers’carbon neutral label adoption behavior.Meanwhile,carbon label cognition,and effort expectancy have no significant impact on consumers’willingness to accept carbon neutral labels,which in turn significantly impacts consumers’carbon neutral label adoption behavior.According to the research findings,increasing the promotion of carbon labeling and improving the practical strategies and management recommendations for carbon label design are proposed.

Structural Design of a Bionic Anti-Clogging Drip Irrigation Emitter Based on Shark Dorsal Fin

Due to the poor anti-clogging performance of the common drip irrigation emitters, this paper designed a new bionic flow channel in the emitter based on the shape of shark dorsal fin. After preliminary structural design, the computational fluid dynamics (CFD) simulation showed that the bionic emitter exhibited superior anti-clogging performance and reasonable hydraulic performance. The passage rate of particles of the bionic emitter in simulation reached 96.3% which was 37.6% higher than 70% of traditional emitter, and the discharge exponent reached 0.4995 which was close to traditional emitter. Physical experiments were consistent with the CFD results, which confirmed the correctness of simulation. After a short cycle anti-clogging performance experiment, the bionic emitter still maintained 96.09% of the initial flow rate.

Catalysis performance comparison of a Br?nsted acid H_2SO_4 and a Lewis acid Al_2(SO_4)_3 in methyl levulinate production from biomass carbohydrates

An experimental investigation was conducted to understand the roles of the Br？nsted acid H2SO4 and Lewis acid Al2（SO4）3 in methyl levulinate（ML） production from biomass carbohydrates, including glucose,fructose and cellulose. The product distributions with different catalysts revealed that the Lewis acid was responsible for the isomerization of methyl glucoside（MG）, producing a significant amount of the subsequent product 5-methoxymethylfurfural（MMF）, while the Br？nsted acid facilitated the production of ML from MMF. Al2（SO4）3 was efficient for monosaccharide conversion but not for cellulose. Using ball-milled cellulose with Al2（SO4）3 resulted in a desired ML yield within a reasonable reaction time. The significant catalysis performances of two types of acids will guide the design of efficient catalytic processes for the selective conversion of biomass into levulinate esters.

Renewable hydrogen production from steam reforming of glycerol(SRG)over ceria-modified Y-alumina supported Ni catalyst

Excess crude glycerol derived as a by-product from biodiesel industry prompts the need to valorise glycerol to value-added chemicals.In this context,catalytic steam reforming of glycerol(SRG) was proposed as a promising and sustainable alternative for producing renewable hydrogen(H2).Herein,the development of nickel(Ni) supported on ceria-modified mesoporous γ-alumina(γ-Al2 O3) catalysts and their applications in catalytic SRG(at550-750℃ atmospheric pressure and weight hourly space velocity,WHSV,of 44,122 ml·g^-1·h^-1(STP)) is presented.Properties of the developed catalysts were characterised using many technique s.The findings show that ceria modification improved Ni dispersion on γ-Al2 O3 catalyst support with highly active small Ni particles,which led to a remarkable catalytic performance with the total glycerol conversion(ca.99%),glycerol conversion into gaseous products(ca.77%) and H2 yield(ca.62%).The formation rate for H2 production(14.4 ×10^(-5)mol·s^-1·g^-1, TOF(H2)=3412 s^-1) was significantly improved with the Ni@12 Ce-Al2 O3 catalyst,representing nearly a 2-fold increase compared with that of the conventional Ni@AI2 O3 catalyst.In addition,the developed catalyst also exhibited comparatively high stability(for 12 h) and coke resistance ability.

Simulation of stimulated Raman scattering signal generation in scattering tissues excited by Bessel beams

Stimulated Raman scattering(SRS)microscopy has the ability of noninvasive imaging of specific chemical bonds and been increasingly used in biomedicine in recent years.Two pulsed Gaussian beams are used in traditional SRS microscopes,providing with high lateral and axial spatial resolution.Because of the tight focus of the Gaussian beam,such an SRS microscopy is difficult to be used for imaging deep targets in scattering tissues.The SRS microscopy based on Bessel beams can solve the imaging problem to a certain extent.Here,we establish a theoretical model to calculate the SRS signal excited by two Bessel beams by integrating the SRS signal generation theory with the fractal propagation method.The fractal model of refractive index turbulence is employed to generate the scattering tissues where the light transport is modeled by the beam propagation method.We model the scattering tissues containing chemicals,calculate the SRS signals stimulated by two Bessel beams,discuss the influence of the fractal model parameters on signal generation,and compare them with those generated by the Gaussian beams.The results show that,even though the modeling parameters have great influence on SRS signal generation,the Bessel beams-based SRS can generate signals in deeper scattering tissues.

Assessment of coal gasification in a pressurized fixed bed gasifier using an ASPEN plus and Euler–Euler model

With the help of Aspen Plus,a two-dimensional unsteady CFD model is developed to simulate the coal gasification process in a fixed bed gasifier.A developed and validated two dimensional CFD model for coal gasification has been used to predict and assess the viability of the syngas generation from coal gasification employing the updraft fixed bed gasifier.The process rate model and the sub-model of gas generation are determined.The particle size variation and char burning during gasification are also taken into account.In order to verify the model and increase the understanding of gasification characteristics,a set of experiments and numerical comparisons have been carried out.The simulated results in the bed are used to predict the composition of syngas and the conversion of carbon.The model proposed in this paper is a promising tool for simulating the coal gasification process in a fixed bed gasifier.

Synthesis of ternary magnetic nanoparticles for enhanced catalytic conversion of biomass-derived methyl levulinate into γ-valerolactone

Conversion of levulinic acid and its esters into versatile y-valerolactone(GVL)is a pivotal and challenging step in biorefineries,limited by high catalyst cost,the use of hydrogen atmosphere,or tedious catalyst preparation and recycling process.Here we have successfully synthesized a ternary magnetic nanoparticle catalyst(Al_(2)O_(3)-ZrO_(2)/Fe_(3)O_(4)(5)),over which biomass-derived methyl levulinate(ML)can be quantitively converted to GVL with an extremely high selectivity of>99%and yield of-98%in the absence of molecular hydrogen.Al_(2)O_(3)-ZrO_(2)/Fe_(3)O_(4)(5)incorporates simultaneously inexpensive alumina and zirconia onto magnetite support by a facile coprecipitation method,giving rise to a core-shell structure,welldistributed acid-base sites,and strong magnetism,as evidenced by the X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM),transmission electron microscopy(TEM),high-angle annular dark-field scanning-TEM(HAADF-STEM),SEM-energy dispersive Xray spectroscopy(SEM-EDX),temperature-programmed desorption of ammonia(NH3-TPD),temperature-programmed desorption of carbon dioxide(CO_(2)-TPD),pyridine-adsorption infrared spectra(Py-IR),and vibrating sample magnetometry(VSM).Such characteristics enable it to be highly active and easily recycled by a magnet for at least five cycles with a slight loss of its catalytic activity,avoiding a time-consuming and energy-intensive reactivation process.It is found that there was a synergistic effect among the metal oxides,and the high efficiency and selectivity originating from such synergism are evidenced by kinetic studies.Furthermore,a reaction mechanism regarding the hydrogenation of ML to GVL is proposed by these findings,coupled with gas chromatography-mass spectrometry(GC-MS)analysis.Accordingly,this readily synthesized and recovered magnetic nanocatalyst for conversion of biomassderived ML into GVL can provide an eco-friendly and safe way for biomass valorization.

Supercontinuum fiber laser-based coherent anti-Stokes Raman scattering microscopy for label-free chemical imaging

Coherent anti-Stokes Raman scattering(CA RS)microscopy can resolve the chemical compo-nents and distribution of living biological systems in a label-firee manner and is favored in several disciplines.Current CA RS microscopes typically use bulky,high-performance solid-state lasers,which are expensive and sensitive to environmental changes.With their relatively low cost and environmental sensitivity,supercontinum fiber(SF)lasers with a small footprint have found increasing use in biomedical applications.Upon these features,in this paper,we homebuilt a low-cost CARS microscope based on a SF laser module(scCA RS microscope).This SF laser module is specially customized by adding a time synchronized seed source channel to the SF laser to form a dual-channel output laser.The performance of the scCARS microscope is evaluated with dimethyl sulfoxide,whose results confirm a spatial resolution of better than 500nm and a detection sensitivity of millimolar concentrations.The dual-color imaging capability is further demonstrated by imaging different species of mixed microspheres.We finally explore the potential of our scCARS microscope by mapping lipid droplets in different cancer cells and corneal stromal lenses.

Early diagnosis and bioimaging of lung adenocarcinoma cells/organs based on spectroscopy machine learning

Early diagnosis and fast detection with a high accuracy rate of lung cancer are important to improve the treatment effect.In this research,an early fast diagnosis and in vivo imaging method for lung adenocarcinoma are proposed by collecting the spectral data from normal and patients'cells/tissues,such as Fourier infrared spectroscopy(FTIR),UV-vis absorbance,and fluorescence spectra using anthocyanin.The FTIR spectra of human normal lung epithelial cells(BEAS-2B cells)and human lung adenocarcinoma cells(A549 cells)were collected.After the data is cleaned,a feature selection algorithm is used to select important wavelengths,and then,the classification models of support vector machine(SVM)and the grid search method are used to select the optimal model parameters(accuracy:96.89%on the training set and 88.57%on the test set).The optimal model is used to classify all samples,and the accuracy is 94.37%.Moreover,the anthocyanin was prepared and used for the intracellular absorbance and fluorescence,and the optimized algorithm was used for classification(accuracy:91.38%on the training set and 80.77%on the test set).Most importantly,the in vivo cancer imaging can be performed using anthocyanin.The results show that there are differences between lung ade-nocarcinoma and normal lung tissues at the molecular level,reflecting the accuracy,intui-tiveness,and feasibility of this algorithm-assistant anthocyanin imaging in lung cancer diagnosis,thus showing the potential to become an accurate and effective technical means for basic research and clinical diagnosis.

Enhanced near-zero-CO2-emission chemicals-oriented oil production from coal with inherent CO2 recycling: Part I—PRB coal fast pyrolysis coupled with CO2/CH4 reforming

In this study,the Powder River Basin(PRB)coal fast pyrolysis was conducted at 700°C in the atmosphere of syngas produced by CH4-CO2 reforming in two different patterns,including the double reactors pattern(the first reactor is for syngas production and the second is for coal pyrolysis)and double layers pattern(catalyst was at upper layer and coal was at lower layer).Besides,pure gases atmosphere including N2,H2,CO,H2-CO were also tested to investigate the mechanism of the coal pyrolysis under different atmospheres.The pyrolysis products including gas,liquid and char were characterized,the result showed that,compared with the inert atmosphere,the tar yield is improved with the reducing atmospheres,as well as the tar quality.The hydrogen partial pressure is the key point for that improvement.In the atmosphere of H2,the tar yield was increased by 31.3%and the contained BTX(benzene,toluene and xylene)and naphthalene were increased by 27.1%and 133.4%.The double reactors pattern also performed outstandingly,with 25.4%increment of tar yield and 25.0%and 79.4%for the BTX and naphthalene.The double layers pattern is not effective enough due to the low temperature(700°C)in which the Ni-based catalyst was not fully activated.

Comparative evaluations of the Monte Carlo-based light propagation simulation packages for optical imaging

Monte Carlo simulation of light propagation in turbid medium has been studied for years.A number of software packages have been developed to handle with such issue.However,it is hard to compare these simulation packages,especially for tissues with complex heterogeneous structures.Here,we first designed a group of mesh datasets generated by Iso2Mesh software,and used them to cross-validate the accuracy and to evaluate the performance of four Monte Carlo-based simulation packages,including Monte Carlo model of steady-state light transport in multi-layered tissues(MCML),tetrahedron-based inhomogeneous Monte Carlo optical simulator(TIMOS),Molecular Optical Simulation Environment(MOSE),and Mesh-based Monte Carlo(MMC).The performance of each package was evaluated based on the designed mesh datasets.The merits and demerits of each package were also discussed.Comparative results showed that the TIMOS package provided the best performance,which proved to be a reliable,efficient,and stable MC simulation package for users.

Combustion Properties of Metal Particles as Components of Modified Double-Base Propellants

Metal particles such as aluminum（ Al）,magnesium（ Mg）,boron（ B） and nickel（ Ni）,as well as Mg/Al alloy（ Mg/Al = 3/4） are currently the most widely used ingredients in modified doublebase propellants. In this contribution,the combustion properties of the metal species are studied by means of the high-speed photography technique and the non-contact wavelet-based measurement of flame temperature distribution. The combustion process of the Al,Mg and Mg/Al samples shows both gas phase reaction and surface oxidation,which yield volatile and nonvolatile products,corresponding to the oxide and suboxide respectively. However,the combustion of B and Ni shows only gas phase reaction,due to their high melting point as well as high enthalpy of vaporization. In addition to the experiments,a hypothetical combustion model has been proposed to clarify the combustion characteristics of metal species in modified double-base propellants.

Clinical Study of Changmaile II Combined with Estrogen and Progesterone in Preventing and Treating Intrauterine Adhesion

Purpose: To explore the clinical efficacy of Changmaile II combined with cyclic estrogen/progesterone therapy in treating hypomenorrhea caused by intrauterine adhesion (IUA) and its effect on the endometrium after the separation procedure for intrauterine adhesion. Methods: Sixty patients with IUA confirmed by hysteroscopy in the Second People’s Hospital of Fujian University of Traditional Chinese Medicine from March 2020 to December 2020 were selected and randomly divided into the control group and the observation group, with 30 cases in each group. After the separation procedure for intrauterine adhesion, the observation group underwent the cyclic estrogen/progesterone therapy alone, while the observation group was administered the in-hospital preparation of Changmaile II in addition to the therapy of the observation group. Menstrual recovery, endometrial thickness, and the diagnostic grading scores of IUA after 3 menstrual cycles were measured in both groups. Results: After the treatment for 3 menstrual cycles, the total effective rate was higher in the observation group (73.33%) than in the control group (53.33%) (P < 0.05). The period flow was heavier in the observation group than in the control group (P < 0.05). The endometrial thickness of both groups was thicker than before treatment (P < 0.05), nonetheless the difference between the groups was not statistically significant (P > 0.05). After treatment, the diagnostic grading scores of IUA were higher in the observation group than in the control group (P < 0.05). Conclusions: Changmaile II combined with estrogen and progesterone artificial cycle therapy could increase the menstrual volume and endometrial thickness of patients with intrauterine adhesion, while promoting the endometrial repair, with better efficacy than artificial cycle therapy alone.

Breakthrough architecture conquers dark current:echoes of Dujiangyan in perovskite photodetectors

Metal halide perovskites(MHPs)photodetectors(PDs)exhibiting outstanding and tunable photoelectric properties have attracted extensive global attention owing to their low-temperature solution-processable fabrication,lightweight nature,and flexibility.1However,MHPs-based PDs still face challenges of high and unstable dark current,which limit their operational stability and practical applications.

Experimental and numerical modeling of carbonized biomass gasification: A critical review

Gasification is one of the most significant and well-researched pathways to produce energy from biomass among the different options available.It is a conversion through thermo-chemical process that takes place within a gasifier,with interconnected factors that have an impact on how well the gasifier works.Gasification of carbonized biomass,which has a variety of effects on both the gasification process and the final product,is a significant method of producing energy from raw biomass that contains a lot of moisture or has non-homogeneous morphology.Although carbonized biomass has the potential to eliminate or significantly reduce tar formation,which is the most difficult aspect of biomass gasifier design and operation,it has not received the attention it merits even though gasification of biomass is a well-known conversion process with extensive research and development spanning all sectors of the process.This review gathers and analyzes the growing number of experimental and numerical modeling approaches in gasification of carbonized biomass based on exact conditions such as type of modeling considerations,feedstock,gasifier,and assessed parameters.The study also provides an overview of various models,such as equilibrium and kinetic rate models and numerical simulations of carbonized biomass gasification schemes based on computational fluid dynamics and Aspen Plus,while comparing the modeling approaches and results for each type of models that are described in the literature.Also,this review encompasses a broad variety of technologies,from laboratory reactors to industrial scale.Overall,this review offers a brief overview of the modeling decisions that must be taken at the beginning of a modeling research.

A型肉毒毒素使用与管理情况分析

分析安徽医科大学第一附属医院门诊A型肉毒毒素使用现状,探讨该药的规范管理。随机抽取安徽医科大学第一附属医院2019年1月至2020年12月A型肉毒毒素的门诊处方300张,分析A型肉毒毒素门诊使用情况、处方的合格率和药事管理情况。300例使用A型肉毒毒素的患者中,用于除皱、眼痉挛、咬肌肥大瘦脸、瘦小腿、组织无力、瘢痕和多汗症的分别为91例(30.33%)、94例(31.33%)、65例(21.67%)、47例(15.67%)、1例(0.33%)、1例(0.33%)和1例(0.33%)。发现不合格处方60张(20.00%),其中未注明剩余药品处理方法的29张(48.33%),无医师和药师双签的26张(43.33%),诊断不明确3张(5%),超说明书剂量用药和未注明处方日期各1张(1.67%)。肉毒素使用过程中出现未注明剩余药品处理、处方没有双签、超剂量、诊断不明确等不合理用药情况,药师在发药审核中拦截并联系医生修改处方后,基本符合国家对毒性药品的管理要求。

In-situ study on structure evolution and gasification reactivity of biomass char with K and Ca catalysts at carbon dioxide atmosphere

The structural evolution and gasification reactivity of biochar prepared from the pyrolysis of wheat straw were investigated by in-situ Raman spectroscopy and thermogravimetric analysis.The Raman spectra consisted of a combination of four Lorentzian bands(D1,D2,D4,G)and one Gaussian band(D3)in the first-order region.The experimental results showed that the addition of catalysts or the presence of ash could improve the CO_(2) gasification reactivity of biochar and result in a larger ID1/IG ratio and a lower IG/IALL ratio,meaning that the carbon structure was less ordered,and there were also more active sites such as amorphous carbon and cross-linked structures;Ca-based catalysts and K-based catalysts changed the evolution of biochar structure in a different way in CO_(2) atmosphere,the ID3/ID1 of Ca-based biochar was close to the value of non-catalyst biochar and decreased slowly,indicating that the Ca-based catalysts can stabilize the aromatic rings,while the IG/IALL of K-based biochar decreases significantly and the ID3/ID1 increased significantly,indicating the increase of carbon structure defects and the cracking of large aromatic rings in bio-char into small ones;a scheme of K and Ca reaction with biochar in CO_(2) gasification process was proposed.

Chronic effects of different fertilization regimes on nirS-type denitrifier communities across the black soil region of Northeast China

Denitrification is one of the major processes causing nitrogen loss from arable soils.This study aimed to investigate the responses of nir S-type denitrifier communities to different chronic fertilization regimes across the black soil region of Northeast China.Soil samples were collected from sites located in the north(NB),middle(MB),and south(SB)of the black soil region of Northeast China,each with four chronic fertilization regimes:no fertilizer(No F),chemical fertilizer(CF),manure(M),and chemical fertilizer plus manure(CFM).Methods of quantitative polymerase chain reaction(q PCR)and Illumina Mi Seq sequencing were applied to assess the abundance and composition of denitrifier communities by targeting the nir S gene.The results showed that the M and CFM regimes significantly increased the abundances of nir S-type denitrifiers compared with No F at the three locations.The majority of nir S sequences were grouped as unclassified denitrifiers,and the different fertilizers induced little variation in the relative abundance of known nir S-type denitrifier taxa.Over 90%of the sequences were shared among the four fertilization regimes at each location,but none of the abundant operational taxonomic units(OTUs)were shared among the three locations.Principal coordinate analysis(PCo A)revealed that the communities of nir S-type denitrifier were separated into three groups that corresponded with their locations.Although similar fertilization regimes did not induce consistent changes in the nir S-type denitrifier communities,soil p H and NO-3-N content simultaneously and significantly influenced the structure of nir S-type denitrifier communities at the three locations.Our results highlight that geographical separation rather than chronic fertilization was the dominant factor determining the nir S-type denitrifier community structures,and similar chronic fertilization regimes did not induce consistent shifts of nir S-type denitrifier communities in the black soils.