采用机械共混法,以导电炭黑(CCB)、天然橡胶(NR)、环氧化天然橡胶(ENR)以及甲基丙烯酸甲酯接枝天然橡胶(MGNR)为原料,制备了复合材料NR/CCB、ENR/CCB、MGNR/CCB、NR/ENR/CCB、NR/MGNR/CCB。研究结果表明,CCB粒子网络在MGNR中比在ENR中...采用机械共混法,以导电炭黑(CCB)、天然橡胶(NR)、环氧化天然橡胶(ENR)以及甲基丙烯酸甲酯接枝天然橡胶(MGNR)为原料,制备了复合材料NR/CCB、ENR/CCB、MGNR/CCB、NR/ENR/CCB、NR/MGNR/CCB。研究结果表明,CCB粒子网络在MGNR中比在ENR中的分散性好,三元共混改性可以进一步提高CCB网络的完整性。在5种复合材料中,NR/ENR/CCB复合材料的有效吸收频宽最宽(3.20 GHz),NR/MGNR/CCB的吸收性能最好(-42.8 d B)。与天然橡胶相比,环氧化改性具有拓宽复合材料有效吸收带宽的作用(拓频),甲基丙烯酸甲酯接枝改性可以增强吸波效能(增效)。结合电磁参数,讨论了复合材料可能的吸波机理。展开更多
Acetone-butanol-ethanol(ABE)fermentation is a primary strategy for producing bio-based n-butanol from abundant renewable biomass.In the typical ABE production chain,distillation is an essential unit for high purity AB...Acetone-butanol-ethanol(ABE)fermentation is a primary strategy for producing bio-based n-butanol from abundant renewable biomass.In the typical ABE production chain,distillation is an essential unit for high purity ABE productions,but has long been criticized by the energy-inefficient processes due to the extremely low solvents concentration received in the upstream fermentation system.Over the past decades,efforts have been dedicated to developing eco-efficient ABE distillation processes aimed at reducing both energy costs and capital investments.In this review,a comprehensive overview on ABE distillation systems is provided from physico-chemical properties in feed and thermodynamics to the process constructions and applications.The recent trends in distillation sequence construction that fitting with the rapid developed upstream in situ product recovery(ISPR)systems are emphasized.Furthermore,towards developing a more efficient ABE distillation system,the review takes a broad overview of the intensification strategies for ABE distillation.Along with systematic introduction of the key examples,the future directions for ABE distillation techniques development are also discussed towards a sustainable and low-carbon emission biorefineries.展开更多
Objective： In the present study, spinal metastatic tumors, brucellar spondylitis and spinal tuberculosis werequantitatively analyzed using dynamic contrast-enhanced magnetic resonance imaging （DCE-MRI） to assess th...Objective： In the present study, spinal metastatic tumors, brucellar spondylitis and spinal tuberculosis werequantitatively analyzed using dynamic contrast-enhanced magnetic resonance imaging （DCE-MRI） to assess thevalue of DCE-MRI in the differential diagnosis of these diseases.Methods： Patients with brucellar spondylitis, spinal tuberculosis or a spinal metastatic tumor （30 cases of each）received conventional MRI and DCE-MRI examination. The volume transfer constant （Ktrans）, rate constant （Kep）,extravascular extracellular volume fraction （Ve） and plasma volume fraction （Vp） of the diseased vertebral bodieswere measured on the perfusion parameter map, and the differences in these parameters between the patients werecompared.Results： For pathological vertebrae in cases of spinal metastatic tumor, brucellar spondylitis and spinaltuberculosis, respectively, the Ktrans values （median ＋ quartile pitch） were 0.989±0.014, 0.720±0.011 and0.317±0.005 min-1; the Kep values were 2.898±0.055, 1.327±0.017 and 0.748±0.006 min-1; the Ve values were0.339±0.008, 0.542±0.013 and 0.428±0.018; the Vp values were 0.048±0.008, 0.035±0.004 and 0.028±0.009; thecorresponding H values were 50.25 （for Ktrans）, 52.47 （for Kep）, 48.33 （for Ve） and 46.56 （for Vp）, and all differenceswere statistically significant （two-sided P〈0.05）.Conclusions： The quantitative analysis of DCE-MRI has a certain value in the differential diagnosis of spinalmetastatic tumor, brucellar spondylitis and spinal tuberculosis.展开更多
Hyperglycemia induces chronic low-grade inflammation(inflammaging),which is a newly identified contributor to diabetes-related tissue lesions,including the inflammatory bone loss in periodontitis.It is also a secondar...Hyperglycemia induces chronic low-grade inflammation(inflammaging),which is a newly identified contributor to diabetes-related tissue lesions,including the inflammatory bone loss in periodontitis.It is also a secondary senescent pattern mediated by an increased burden of senescent cells and senescence-associated secretory phenotype(SASP).Macrophage is a key SASPspreading cell and may contribute to the maintenance of SASP response in the periodontal microenvironment.Using a transgenic diabetic model(BLKS/J-Lepr^(db)/lepr^(db)mice)we identified striking senescence of the periodontium in young(18-wk)-diabetic mice accompanied by amassed p16^(+)-macrophages and enhanced early SASP response.Exposed to high glucose in vitro,bone marrow-derived macrophage(BMDM)revealed a strong GLUT1 m RNA response driving the elevated-glucose uptake.GLUT1 is a representative and facilitative glucose transporter in macrophages with potential roles in hyperglycemia-induced inflammation.In this study,both GLUT1 and the downstream GTPase Rheb expression upregulated in the gingiva of diabetic mice with impaired condition.Furthermore,SASP release and p16/p21 signaling were proven to be triggered by m TOR phosphorylation in BMDM and antagonized by restricting glucose uptake in GLUT1^(-/-)BMDM.Taken together,our findings suggest that elevated-GLUT1 sensor responded to high glucose is important for macrophage senescence and SASP response,generated as a result of hyperglycemia,and it is a potential molecular mechanism for the exacerbation of periodontitis in diabetes.展开更多
Objective:To explore the structural and functional characteristics of the fecal-associated microbiome(FAM)in a traditional Chinese medicine(TCM)qi-deficiency constitution(QDC)by comparing with balanced constitution(BC...Objective:To explore the structural and functional characteristics of the fecal-associated microbiome(FAM)in a traditional Chinese medicine(TCM)qi-deficiency constitution(QDC)by comparing with balanced constitution(BC)and screen the related biomarkers.Methods:In this cross-sectional study,the TCM constitutions of subjects were determined based on published the Classification and Determination of constitution in TCM and further confirmed by a TCM clinician.Clinical characteristics were recorded,and fecal samples were collected for 16S rDNA sequencing using the Illumina Miseq platform.The FAM structure was described using alpha-diversity indexes,beta-diversity indexes,and the relative abundances of the dominant taxa.Differences in the FAM distribution and function were analyzed with a Wilcoxon rank-sum test,MetagenomeSeq,and LEfSe analysis,after which a receiver operating characteristic curve based on the specific operational taxonomic units(OTUs)was constructed to calculate the area under the curve.Results:Our study population was composed of 22 BCs and 9 QDCs.There were no significant differences between the two groups in the distribution of clinical characteristics or alpha-diversity indexes,except for the sweets preference and blood glucose level.In principal coordinate analysis and partial least squares discriminant analysis,the bacterial communities in the BC group samples and QDC group samples clustered separately.Notably,there were 214 OTUs significantly distributed between groups in the MetagenomeSeq analysis,200 OTUs identified by the Wilcoxon rank-sum test,and 6 OTUs found by the LEfSe analysis.Predicted function analysis revealed that six metabolic pathways were distinctly distributed between the two groups.The area under the curve for the receiver operating characteristic curve based on the four specific OTUs was 0.88.Conclusion:Unique FAM structural and related functional characteristics are displayed in individuals with a QDC,and four specific OTUs could be used as QDC biomarkers to assist in clinical diagnosis.展开更多
In fractured geothermal reservoirs,the fracture networks and internal fluid flow behaviors can significantly impact the thermal performance.In this study,we proposed a non-Darcy rough discrete fracture network(NR-DFN)...In fractured geothermal reservoirs,the fracture networks and internal fluid flow behaviors can significantly impact the thermal performance.In this study,we proposed a non-Darcy rough discrete fracture network(NR-DFN)model that can simultaneously consider the fracture evolution and non-Darcy flow dynamics in studying the thermo-hydro-mechanical(THM)coupling processes for heat extraction in geothermal reservoir.We further employed the model on the Habanero enhanced geothermal systems(EGS)project located in Australia.First,our findings illustrate a clear spatial-temporal variation in the thermal stress and pressure perturbations,as well as uneven spatial distribution of shear failure in 3D fracture networks.Activated shear failure is mainly concentrated in the first fracture cluster.Secondly,channeling flow have also been observed in DFNs during heat extraction and are further intensified by the expansion of fractures driven by thermal stresses.Moreover,the combined effect of non-Darcy flow and fracture evolution triggers a rapid decline in the resulting heat rate and temperature.The NR-DFN model framework and the Habanero EGS's results illustrate the importance of both fracture evolution and non-Darcy flow on the efficiency of EGS production and have the potential to promote the development of more sustainable and efficient EGS operations for stakeholders.展开更多
Objective: This study aimed to explore the structural and functional characteristics of the fecalassociated microbiome(FAM) between the phlegm-dampness constitution(PDC) and balanced constitution(BC), and to screen th...Objective: This study aimed to explore the structural and functional characteristics of the fecalassociated microbiome(FAM) between the phlegm-dampness constitution(PDC) and balanced constitution(BC), and to screen the related specific operational taxonomic unit(OTU) biomarkers.Methods: This was a cross-sectional study. After strictly identifying the constitution of subjects, their clinical index was recorded and counted. Fecal samples were collected for 16S rDNA sequencing. Alpha diversity, beta diversity, and the relative abundance of dominant bacterial taxa were used to describe the FAM structure, and the Wilcoxon rank-sum test, Metagenome Seq, and linear discriminant analysis effect size(LEf Se) were used to screen specific bacterial taxa. Specific OTUs were screened to construct receiver operating characteristic(ROC) curves.Results: Thirty-two subjects were enrolled, including 22 subjects with BC and 10 subjects with PDC.There were significant differences in cold preference, levels of aspartate transaminase, β2-microglobulin,and creatine kinase MB, and alpha diversity indices(Shannon and Shannoneven) between the two groups. In principal coordinate analysis by abund-jaccard distance measure and partial least squares discriminant analysis, bacterial communities clustered separately between the two groups. Furthermore,based on Metagenome Seq, LEf Se, and the Wilcoxon rank-sum test, a total of 43, 18, and 130 OTUs were differentially distributed between BC group and PDC group, respectively, and OTU200, OTU133, and OTU353 were screened when P≤.01. The area under the ROC curve constructed from the 3 selected OTUs was 0.93.Conclusion: The FAM structure and related functional characteristics of the PDC group differed from those of the BC group. In particular, OTU200, OTU133, and OTU353 can be used as unique markers of PDC to assist clinical diagnosis.展开更多
The Sulige tight sandstone gas reservoir is marked by low permeability,intricate pore structures,and notable lateral heterogeneity,making it difficult to predict the productivity of fractured horizontal wells in the r...The Sulige tight sandstone gas reservoir is marked by low permeability,intricate pore structures,and notable lateral heterogeneity,making it difficult to predict the productivity of fractured horizontal wells in the reservoir.In this study,a productivity prediction model for fractured horizontal wells is developed based on the characteristics of the Sulige gas reservoir,including its high start-up pressure gradient,strong stress sensitivity,obvious non-Darcy flow,and typical slippage and diffusion effects.This new model fully accounts for each hydraulic fracture in the horizontal wells based on the superposition principle and Green's function.This model facilitates efficient productivity calculations and enables rapid quantitative analysis of the influencing factors specific to horizontal wells with hydraulic fractures,fully integrating the specific characteristics of the Sulige gas field.The accuracy of this model is tested against field data from Wells LX1 and LX2 in the Sulige field,indicating good agreement between the predicted values and field data.Well LX2 is used as a case study to analyze the influences of geological and engineering factors on well productivity.The following conclusions are drawn:1)Well productivity is notably influenced by the start-up pressure gradient and stress sensitivity,with a minor impact from non-Darcy effects.2)Productivity linearly decreases with increased hydraulic fracture spacing.3)Productivity increases,and the increment rate gradually decreases,with increases in the length and conductivity of the hydraulic fractures.This model provides valuable guidance on predicting productivity in tight sandstone gas reservoirs,such as that of the Sulige gas field.展开更多
A strongly declining aerosol radiative effect has been observed in China since 2013 after implementing the clean air action,yet its impact on wheat(Triticum aestivum L.)production remains unclear.We use satellite meas...A strongly declining aerosol radiative effect has been observed in China since 2013 after implementing the clean air action,yet its impact on wheat(Triticum aestivum L.)production remains unclear.We use satellite measures and a biophysical crop model to assess the impact of aerosol-induced radiative perturbations on winter wheat production in the agricultural belt of Henan province from 2013 to 2018.After calibrating parameters with the extended Fourier Amplitude Sensitivity Test(EFAST)and the generalized likelihood uncertainty estimation(GLUE)method,the DSSAT CERES-Wheat model was able to simulate crop biomass and yield more accurately.We found that the aerosol negatively impacted wheat biomass by 21.87%and yield by 22.48%from 2006 to 2018,and the biomass effects from planting to anthesis were more significant compared to anthesis to maturity.Due to the strict clean air action,under all-sky conditions,the surface solar shortwave radiation(SSR)in 2018 increased by about 7.08%over 2006-2013 during the wheat growing seasons.As a result of the improvement of crop photosynthesis,winter wheat biomass and yield increased by an average of 5.46%and 2.9%,respectively.Our findings show that crop carbon uptake and yield will benefit from the clean air action in China,helping to ensure national food and health security.展开更多
The linear and nonlinear simulations are carried out using the gyrokinetic code NLT for the electrostatic instabilities in the core region of a deuterium plasma based on the International Thermonuclear Experimental Re...The linear and nonlinear simulations are carried out using the gyrokinetic code NLT for the electrostatic instabilities in the core region of a deuterium plasma based on the International Thermonuclear Experimental Reactor(ITER)baseline scenario.The kinetic electron effects on the linear frequency and nonlinear transport are studied by adopting the adiabatic electron model and the fully drift-kinetic electron model in the NLT code,respectively.The linear simulations focus on the dependence of linear frequency on the plasma parameters,such as the ion and electron temperature gradientsκ_(Ti,e)≡R=L_(Ti,e),the density gradientκ_(n)≡R/L_(n)and the ion-electron temperature ratioτ=T_(e)=T_(i).Here,is the major radius,and T_(e)and T_(i)denote the electron and ion temperatures,respectively.L_(A)=-(δ_(r)lnA)^(-1)is the gradient scale length,with denoting the density,the ion and electron temperatures,respectively.In the kinetic electron model,the ion temperature gradient(ITG)instability and the trapped electron mode(TEM)dominate in the small and large k_(θ)region,respectively,wherek_(θ)is the poloidal wavenumber.The TEMdominant region becomes wider by increasing(decreasing)κ_(T_(e))(κ_(T_(i)))or by decreasingκ_(n).For the nominal parameters of the ITER baseline scenario,the maximum growth rate of dominant ITG instability in the kinetic electron model is about three times larger than that in the adiabatic electron model.The normalized linear frequency depends on the value ofτ,rather than the value of T_(e)or T_(i),in both the adiabatic and kinetic electron models.The nonlinear simulation results show that the ion heat diffusivity in the kinetic electron model is quite a lot larger than that in the adiabatic electron model,the radial structure is finer and the time oscillation is more rapid.In addition,the magnitude of the fluctuated potential at the saturated stage peaks in the ITGdominated region,and contributions from the TEM(dominating in the higher k_(θ)region)to the nonlinear transport can be neglected.In the adiabatic electron model,the zonal radial electric field is found to be mainly driven by the turbulent energy flux,and the contribution of turbulent poloidal Reynolds stress is quite small due to the toroidal shielding effect.However,in the kinetic electron model,the turbulent energy flux is not strong enough to drive the zonal radial electric field in the nonlinear saturated stage.The kinetic electron effects on the mechanism of the turbulence-driven zonal radial electric field should be further investigated.展开更多
Objective:To investigate whether the specific traditional Chinese medicine(TCM)constitution of individuals can be defined by certain biological indexes instead of answering the questionnaire,and to explore the possibi...Objective:To investigate whether the specific traditional Chinese medicine(TCM)constitution of individuals can be defined by certain biological indexes instead of answering the questionnaire,and to explore the possibility of discriminating nine TCM constitutions from each other simultaneously using biological indexes.Methods:Blood and urine samples from 152 individuals with nine TCM constitutions were collected,and the related biological indexes were analyzed combining ANOVA,multiple comparison,discriminant analysis,and support vector machine.Results:We found that 4 out of 24 blood routine indexes,7 out of 10 urine routine indexes,and 12 out of 32 biochemical indexes showed differences among the constitutions.High-sensitivity C-reactive protein,apolipoprotein A1,and alkaline phosphatase were potential candidates for screening out individuals with unbalanced constitutions.Combining uric acid,high-density lipoprotein,apolipoprotein A1,creatine kinase,total protein,aspartate aminotransferase,total bile acid,dehydrogenase,sodium,and calcium levels had the potential to directly distinguish the nine TCM constitutions from each other.Among these indexes,the highest ratio of discriminant analysis between two constitutions was 95.5%,while the lowest was 66.1%.Conclusion:Our results suggest that some biochemical and urine indexes are related to various TCM constitutions,and thus they have the potential to be used for TCM constitution classification.展开更多
The fast and convenient demultiplex of optical vortex(OV) mode is crucial for its further application. We propose a novel approach that combines classic Young's doublet with an OV source to effectively identify th...The fast and convenient demultiplex of optical vortex(OV) mode is crucial for its further application. We propose a novel approach that combines classic Young's doublet with an OV source to effectively identify the OV mode through the analysis of interference patterns. The interference patterns of the OV source incident on the double slits can be perfectly illustrated by using both the classical double-slit interference method and the Huygens–Fresnel principle. The interference fringes will twist along the negative or positive direction of x axis when topological charge(TC)l>0 or l<0, and the degree of the movement varies with the TC, allowing for a quantitative display of the OV characteristics through the interference patterns. Additionally, we deduce analytically that the zeroth-order interference fringe has a linear relationship with the TC and the vertical position. These findings highlight the ability to identify the OV mode by analyzing the interference patterns produced by Young's doublet.展开更多
We propose multi-core conformal lenses by combining conformal transformation optics with absolute instruments.Depending on the cores and incident angles,the conformal lenses have tunable functionalities like focusing,...We propose multi-core conformal lenses by combining conformal transformation optics with absolute instruments.Depending on the cores and incident angles,the conformal lenses have tunable functionalities like focusing,reflection,and transparency,thereby providing a feasible general method for designing multi-functional devices.展开更多
Objective:To clarify the structural and functional characteristics of the gut microbiota in individuals with qi stagnation constitution(QSC)and identify the potential biomarkers related to QSC.Methods:This cross-secti...Objective:To clarify the structural and functional characteristics of the gut microbiota in individuals with qi stagnation constitution(QSC)and identify the potential biomarkers related to QSC.Methods:This cross-sectional study involved individuals with QSC and balanced constitution(BC)confirmed by TCM clinicians.The clinical features were recorded,and fecal samples were collected for 16S rDNA sequencing.The structure of the fecal-associated microbiome(FAM)was described by the alpha-diversity indexes,beta-distances,and relative abundances of dominant taxa.The differences in FAM distribution were analyzed by the Wilcoxon rank-sum test,MetagenomeSeq,and LEfSe analysis.The 16S rDNA gene sequences were assigned to the KEGG dataset to predict the functional information of bacterial metabolic pathways by using PICRUSt.Differences in functional pathways between groups were assessed with the Wilcoxon rank-sum test.The ROC curve based on specific operational taxonomic units(OTUs)was constructed,and the AUC was calculated.Results:Twenty-two individuals with BC and 8 with QSC were recruited.Significant differences between the two groups were found in body mass index,health status,and low-density lipoprotein,etc.There was no significant difference in the alpha-diversity index.PCoA showed no evident clustering of bacterial communities according to constitutions.Bacteroidaceae,Lachnospiraceae,Ruminococcaceae,and Prevotellaceae were the four common bacteria with high abundances.Notably,MetagenomeSeq,LEfSe analysis,and the Wilcoxon rank-sum test identified significantly different distributions of 66,42,and 36 OTUs,respectively.Predictive function analysis showed that 13 metabolic pathways were significantly differentially distributed,including those related to fatty acid synthesis.Five specific OTUs were selected as potential biomarkers of a QSC,and the AUC was 0.94.Conclusion:Individuals with QSC have unique FAM structure and related functional characteristics.Five specific OTUs were identified to serve as potentially effective biomarkers related to QSC.展开更多
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Efficient dry beneficiation of low-grade oil shale requires precise regulation of bed density in high-density gas-solid fluidized beds.This study develops a ternary dense-medium system comprising ferrosilicon powder,m...Efficient dry beneficiation of low-grade oil shale requires precise regulation of bed density in high-density gas-solid fluidized beds.This study develops a ternary dense-medium system comprising ferrosilicon powder,magnetite powder and oil shale particles,and investigates the coupling between medium composition,hydrodynamics and machine-learning-assisted density prediction.The results demonstrated that the ternary density regulation strategy significantly enhances fluidization uniformity and separation efficiency in the dry dense-medium fluidized bed.When the oil-shale mass fraction increases from 0%to 20%,the critical fluidization velocity rises from 12.54 to 14.08 cm/s,while the bed expansion ratio grows from 5.19%to 8.83%.Compared with the conventional binary medium,the ternary system lowers the mean bed density from 2.567 to 2.382 g cm^(-3) and achieves the minimum density fluctuation(standard deviation,SD=0.097)at an optimal oil-shale mass fraction of 8%.A back-propagation neural network optimized by a genetic algorithm(GA-BP)using seven process features predicts bed density with correlation coefficient R=0.979 and root-mean-square error(RMSE)of 0.049 on 167 test samples—an 18%error reduction over the conventional BP model.The proposed ternary medium strategy and GA-BP predictor therefore offer a robust framework for stable,energy-efficient dry separationofoil shale.展开更多
Efficient dry separation is essential for utilizing low-grade oil shale.This study developed a ternary high-density gas–solid fluidized bed system using ferrosilicon powder,magnetite powder,and D-class oil shale part...Efficient dry separation is essential for utilizing low-grade oil shale.This study developed a ternary high-density gas–solid fluidized bed system using ferrosilicon powder,magnetite powder,and D-class oil shale particles,focusing on the impact of apparent viscosity on particle settling.Results showed that viscosity was influenced by medium composition,particle size,and flow structure.In the binary system of B−silicon and B+magnetite,minimum viscosity(0.782 Pa s)was reached at a 40%ferrosilicon ratio.In the ternary system,viscosity increased nonlinearly with oil shale content,with 8%being the critical threshold where fluidization stability declined.Gas velocity significantly affected viscosity distribution,with moderate increases improving flow uniformity and reducing viscosity by 32%–40%.However,excessive velocity caused bubble coalescence and increased viscosity fluctuations,with standard deviation rising from 0.0065 to 0.0191 Pa s.Sedimentation tests showed that the middle bed region provided optimal separation at low gas velocity,while higher velocities shifted separation to the upper region.When gas velocity exceeds 0.45 m/s,the best separation efficiency is achieved.This study clarifies the relationship between viscosity and separation performance,providing guidance for optimizing dry oil shale separation.展开更多
Though an accurate discretization approach for gas flow dynamics, the method of characteristics (MOC) is liable to instability for inappropriate step sizes. This letter addresses the numerical stability limitation of ...Though an accurate discretization approach for gas flow dynamics, the method of characteristics (MOC) is liable to instability for inappropriate step sizes. This letter addresses the numerical stability limitation of MOC, in the context of lEGS's optimal scheduling. Specifically, the proposed method enables flexible temporal step sizes without sacrificing accuracy, significantly reducing non-convergence due to numerical oscillations. The effectiveness of the proposed method is validated through case studies in different simulation settings.展开更多
文摘采用机械共混法,以导电炭黑(CCB)、天然橡胶(NR)、环氧化天然橡胶(ENR)以及甲基丙烯酸甲酯接枝天然橡胶(MGNR)为原料,制备了复合材料NR/CCB、ENR/CCB、MGNR/CCB、NR/ENR/CCB、NR/MGNR/CCB。研究结果表明,CCB粒子网络在MGNR中比在ENR中的分散性好,三元共混改性可以进一步提高CCB网络的完整性。在5种复合材料中,NR/ENR/CCB复合材料的有效吸收频宽最宽(3.20 GHz),NR/MGNR/CCB的吸收性能最好(-42.8 d B)。与天然橡胶相比,环氧化改性具有拓宽复合材料有效吸收带宽的作用(拓频),甲基丙烯酸甲酯接枝改性可以增强吸波效能(增效)。结合电磁参数,讨论了复合材料可能的吸波机理。
基金funded by the National Natural Science Foundation of China(22078018)the Natural Science Foundation of Beijing(2222016).
文摘Acetone-butanol-ethanol(ABE)fermentation is a primary strategy for producing bio-based n-butanol from abundant renewable biomass.In the typical ABE production chain,distillation is an essential unit for high purity ABE productions,but has long been criticized by the energy-inefficient processes due to the extremely low solvents concentration received in the upstream fermentation system.Over the past decades,efforts have been dedicated to developing eco-efficient ABE distillation processes aimed at reducing both energy costs and capital investments.In this review,a comprehensive overview on ABE distillation systems is provided from physico-chemical properties in feed and thermodynamics to the process constructions and applications.The recent trends in distillation sequence construction that fitting with the rapid developed upstream in situ product recovery(ISPR)systems are emphasized.Furthermore,towards developing a more efficient ABE distillation system,the review takes a broad overview of the intensification strategies for ABE distillation.Along with systematic introduction of the key examples,the future directions for ABE distillation techniques development are also discussed towards a sustainable and low-carbon emission biorefineries.
基金funded by the National Natural Science Foundation of China (No. 81460259)
文摘Objective： In the present study, spinal metastatic tumors, brucellar spondylitis and spinal tuberculosis werequantitatively analyzed using dynamic contrast-enhanced magnetic resonance imaging （DCE-MRI） to assess thevalue of DCE-MRI in the differential diagnosis of these diseases.Methods： Patients with brucellar spondylitis, spinal tuberculosis or a spinal metastatic tumor （30 cases of each）received conventional MRI and DCE-MRI examination. The volume transfer constant （Ktrans）, rate constant （Kep）,extravascular extracellular volume fraction （Ve） and plasma volume fraction （Vp） of the diseased vertebral bodieswere measured on the perfusion parameter map, and the differences in these parameters between the patients werecompared.Results： For pathological vertebrae in cases of spinal metastatic tumor, brucellar spondylitis and spinaltuberculosis, respectively, the Ktrans values （median ＋ quartile pitch） were 0.989±0.014, 0.720±0.011 and0.317±0.005 min-1; the Kep values were 2.898±0.055, 1.327±0.017 and 0.748±0.006 min-1; the Ve values were0.339±0.008, 0.542±0.013 and 0.428±0.018; the Vp values were 0.048±0.008, 0.035±0.004 and 0.028±0.009; thecorresponding H values were 50.25 （for Ktrans）, 52.47 （for Kep）, 48.33 （for Ve） and 46.56 （for Vp）, and all differenceswere statistically significant （two-sided P〈0.05）.Conclusions： The quantitative analysis of DCE-MRI has a certain value in the differential diagnosis of spinalmetastatic tumor, brucellar spondylitis and spinal tuberculosis.
基金supported by the National Natural Science Foundation of China[Grant Numbers 8187077981991500+1 种基金81991502]the International Cooperation Project of Chengdu Municipal Science and Technology Bureau[Grant Number 2015-GH0200035-HZ]。
文摘Hyperglycemia induces chronic low-grade inflammation(inflammaging),which is a newly identified contributor to diabetes-related tissue lesions,including the inflammatory bone loss in periodontitis.It is also a secondary senescent pattern mediated by an increased burden of senescent cells and senescence-associated secretory phenotype(SASP).Macrophage is a key SASPspreading cell and may contribute to the maintenance of SASP response in the periodontal microenvironment.Using a transgenic diabetic model(BLKS/J-Lepr^(db)/lepr^(db)mice)we identified striking senescence of the periodontium in young(18-wk)-diabetic mice accompanied by amassed p16^(+)-macrophages and enhanced early SASP response.Exposed to high glucose in vitro,bone marrow-derived macrophage(BMDM)revealed a strong GLUT1 m RNA response driving the elevated-glucose uptake.GLUT1 is a representative and facilitative glucose transporter in macrophages with potential roles in hyperglycemia-induced inflammation.In this study,both GLUT1 and the downstream GTPase Rheb expression upregulated in the gingiva of diabetic mice with impaired condition.Furthermore,SASP release and p16/p21 signaling were proven to be triggered by m TOR phosphorylation in BMDM and antagonized by restricting glucose uptake in GLUT1^(-/-)BMDM.Taken together,our findings suggest that elevated-GLUT1 sensor responded to high glucose is important for macrophage senescence and SASP response,generated as a result of hyperglycemia,and it is a potential molecular mechanism for the exacerbation of periodontitis in diabetes.
基金the National Natural Science Foundation of China(81430099 and 31500704)International Science&Technology Cooperation Program of China(2014DFA32950)Research program from Beijing University of Chinese Medicine(1000041510049,BUCM-2019-JCRC006 and 2019-JYB-TD013).
文摘Objective:To explore the structural and functional characteristics of the fecal-associated microbiome(FAM)in a traditional Chinese medicine(TCM)qi-deficiency constitution(QDC)by comparing with balanced constitution(BC)and screen the related biomarkers.Methods:In this cross-sectional study,the TCM constitutions of subjects were determined based on published the Classification and Determination of constitution in TCM and further confirmed by a TCM clinician.Clinical characteristics were recorded,and fecal samples were collected for 16S rDNA sequencing using the Illumina Miseq platform.The FAM structure was described using alpha-diversity indexes,beta-diversity indexes,and the relative abundances of the dominant taxa.Differences in the FAM distribution and function were analyzed with a Wilcoxon rank-sum test,MetagenomeSeq,and LEfSe analysis,after which a receiver operating characteristic curve based on the specific operational taxonomic units(OTUs)was constructed to calculate the area under the curve.Results:Our study population was composed of 22 BCs and 9 QDCs.There were no significant differences between the two groups in the distribution of clinical characteristics or alpha-diversity indexes,except for the sweets preference and blood glucose level.In principal coordinate analysis and partial least squares discriminant analysis,the bacterial communities in the BC group samples and QDC group samples clustered separately.Notably,there were 214 OTUs significantly distributed between groups in the MetagenomeSeq analysis,200 OTUs identified by the Wilcoxon rank-sum test,and 6 OTUs found by the LEfSe analysis.Predicted function analysis revealed that six metabolic pathways were distinctly distributed between the two groups.The area under the curve for the receiver operating characteristic curve based on the four specific OTUs was 0.88.Conclusion:Unique FAM structural and related functional characteristics are displayed in individuals with a QDC,and four specific OTUs could be used as QDC biomarkers to assist in clinical diagnosis.
基金funded by the National Natural Science Foundation of China (No.U22A20166)Science and Technology Foundation of Guizhou Province (No.QKHJC-ZK[2023]YB074)+2 种基金Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical EngineeringInstitute of Rock and Soil MechanicsChinese Academy of Sciences (No.SKLGME022009)。
文摘In fractured geothermal reservoirs,the fracture networks and internal fluid flow behaviors can significantly impact the thermal performance.In this study,we proposed a non-Darcy rough discrete fracture network(NR-DFN)model that can simultaneously consider the fracture evolution and non-Darcy flow dynamics in studying the thermo-hydro-mechanical(THM)coupling processes for heat extraction in geothermal reservoir.We further employed the model on the Habanero enhanced geothermal systems(EGS)project located in Australia.First,our findings illustrate a clear spatial-temporal variation in the thermal stress and pressure perturbations,as well as uneven spatial distribution of shear failure in 3D fracture networks.Activated shear failure is mainly concentrated in the first fracture cluster.Secondly,channeling flow have also been observed in DFNs during heat extraction and are further intensified by the expansion of fractures driven by thermal stresses.Moreover,the combined effect of non-Darcy flow and fracture evolution triggers a rapid decline in the resulting heat rate and temperature.The NR-DFN model framework and the Habanero EGS's results illustrate the importance of both fracture evolution and non-Darcy flow on the efficiency of EGS production and have the potential to promote the development of more sustainable and efficient EGS operations for stakeholders.
基金supported by National Natural Science Foundation of China (81430099)National Key Research and Development Project (2019YFC1710104)the 111 Project (B21028)。
文摘Objective: This study aimed to explore the structural and functional characteristics of the fecalassociated microbiome(FAM) between the phlegm-dampness constitution(PDC) and balanced constitution(BC), and to screen the related specific operational taxonomic unit(OTU) biomarkers.Methods: This was a cross-sectional study. After strictly identifying the constitution of subjects, their clinical index was recorded and counted. Fecal samples were collected for 16S rDNA sequencing. Alpha diversity, beta diversity, and the relative abundance of dominant bacterial taxa were used to describe the FAM structure, and the Wilcoxon rank-sum test, Metagenome Seq, and linear discriminant analysis effect size(LEf Se) were used to screen specific bacterial taxa. Specific OTUs were screened to construct receiver operating characteristic(ROC) curves.Results: Thirty-two subjects were enrolled, including 22 subjects with BC and 10 subjects with PDC.There were significant differences in cold preference, levels of aspartate transaminase, β2-microglobulin,and creatine kinase MB, and alpha diversity indices(Shannon and Shannoneven) between the two groups. In principal coordinate analysis by abund-jaccard distance measure and partial least squares discriminant analysis, bacterial communities clustered separately between the two groups. Furthermore,based on Metagenome Seq, LEf Se, and the Wilcoxon rank-sum test, a total of 43, 18, and 130 OTUs were differentially distributed between BC group and PDC group, respectively, and OTU200, OTU133, and OTU353 were screened when P≤.01. The area under the ROC curve constructed from the 3 selected OTUs was 0.93.Conclusion: The FAM structure and related functional characteristics of the PDC group differed from those of the BC group. In particular, OTU200, OTU133, and OTU353 can be used as unique markers of PDC to assist clinical diagnosis.
基金support from the Natural Science Foundation of Sichuan Province(Grant Nos.2022NSFSC0185 and 2023NSFSC0938)the National Natural Science Foundation of China(Grant No.42172313)are appreciated.
文摘The Sulige tight sandstone gas reservoir is marked by low permeability,intricate pore structures,and notable lateral heterogeneity,making it difficult to predict the productivity of fractured horizontal wells in the reservoir.In this study,a productivity prediction model for fractured horizontal wells is developed based on the characteristics of the Sulige gas reservoir,including its high start-up pressure gradient,strong stress sensitivity,obvious non-Darcy flow,and typical slippage and diffusion effects.This new model fully accounts for each hydraulic fracture in the horizontal wells based on the superposition principle and Green's function.This model facilitates efficient productivity calculations and enables rapid quantitative analysis of the influencing factors specific to horizontal wells with hydraulic fractures,fully integrating the specific characteristics of the Sulige gas field.The accuracy of this model is tested against field data from Wells LX1 and LX2 in the Sulige field,indicating good agreement between the predicted values and field data.Well LX2 is used as a case study to analyze the influences of geological and engineering factors on well productivity.The following conclusions are drawn:1)Well productivity is notably influenced by the start-up pressure gradient and stress sensitivity,with a minor impact from non-Darcy effects.2)Productivity linearly decreases with increased hydraulic fracture spacing.3)Productivity increases,and the increment rate gradually decreases,with increases in the length and conductivity of the hydraulic fractures.This model provides valuable guidance on predicting productivity in tight sandstone gas reservoirs,such as that of the Sulige gas field.
基金supported by the Joint Funds of the National Natural Science Foundation of China(No.U21A2014)the Science and Technology Development Program of Henan Province(No.232102321032)the support from the Henan Dabieshan National Field Observation and Research Station of Forest Ecosystem。
文摘A strongly declining aerosol radiative effect has been observed in China since 2013 after implementing the clean air action,yet its impact on wheat(Triticum aestivum L.)production remains unclear.We use satellite measures and a biophysical crop model to assess the impact of aerosol-induced radiative perturbations on winter wheat production in the agricultural belt of Henan province from 2013 to 2018.After calibrating parameters with the extended Fourier Amplitude Sensitivity Test(EFAST)and the generalized likelihood uncertainty estimation(GLUE)method,the DSSAT CERES-Wheat model was able to simulate crop biomass and yield more accurately.We found that the aerosol negatively impacted wheat biomass by 21.87%and yield by 22.48%from 2006 to 2018,and the biomass effects from planting to anthesis were more significant compared to anthesis to maturity.Due to the strict clean air action,under all-sky conditions,the surface solar shortwave radiation(SSR)in 2018 increased by about 7.08%over 2006-2013 during the wheat growing seasons.As a result of the improvement of crop photosynthesis,winter wheat biomass and yield increased by an average of 5.46%and 2.9%,respectively.Our findings show that crop carbon uptake and yield will benefit from the clean air action in China,helping to ensure national food and health security.
基金supported by the National MCF Energy R&D Program of China(No.2019YFE03060000)National Natural Science Foundation of China(Nos.12005063,12375215 and 12175034)the Collaborative Innovation Program of Hefei Science Center,CAS(No.2022HSC-CIP008).
文摘The linear and nonlinear simulations are carried out using the gyrokinetic code NLT for the electrostatic instabilities in the core region of a deuterium plasma based on the International Thermonuclear Experimental Reactor(ITER)baseline scenario.The kinetic electron effects on the linear frequency and nonlinear transport are studied by adopting the adiabatic electron model and the fully drift-kinetic electron model in the NLT code,respectively.The linear simulations focus on the dependence of linear frequency on the plasma parameters,such as the ion and electron temperature gradientsκ_(Ti,e)≡R=L_(Ti,e),the density gradientκ_(n)≡R/L_(n)and the ion-electron temperature ratioτ=T_(e)=T_(i).Here,is the major radius,and T_(e)and T_(i)denote the electron and ion temperatures,respectively.L_(A)=-(δ_(r)lnA)^(-1)is the gradient scale length,with denoting the density,the ion and electron temperatures,respectively.In the kinetic electron model,the ion temperature gradient(ITG)instability and the trapped electron mode(TEM)dominate in the small and large k_(θ)region,respectively,wherek_(θ)is the poloidal wavenumber.The TEMdominant region becomes wider by increasing(decreasing)κ_(T_(e))(κ_(T_(i)))or by decreasingκ_(n).For the nominal parameters of the ITER baseline scenario,the maximum growth rate of dominant ITG instability in the kinetic electron model is about three times larger than that in the adiabatic electron model.The normalized linear frequency depends on the value ofτ,rather than the value of T_(e)or T_(i),in both the adiabatic and kinetic electron models.The nonlinear simulation results show that the ion heat diffusivity in the kinetic electron model is quite a lot larger than that in the adiabatic electron model,the radial structure is finer and the time oscillation is more rapid.In addition,the magnitude of the fluctuated potential at the saturated stage peaks in the ITGdominated region,and contributions from the TEM(dominating in the higher k_(θ)region)to the nonlinear transport can be neglected.In the adiabatic electron model,the zonal radial electric field is found to be mainly driven by the turbulent energy flux,and the contribution of turbulent poloidal Reynolds stress is quite small due to the toroidal shielding effect.However,in the kinetic electron model,the turbulent energy flux is not strong enough to drive the zonal radial electric field in the nonlinear saturated stage.The kinetic electron effects on the mechanism of the turbulence-driven zonal radial electric field should be further investigated.
基金supported by the National Key Research and Development Project (2019YFC1710104)the National Natural Science Foundation of China (81430099)+1 种基金the International Cooperation and Exchanges (2014DFA32950)the Fundamental Research Funds for the Central Universities (2020-JYB-XJSJJ-026)
文摘Objective:To investigate whether the specific traditional Chinese medicine(TCM)constitution of individuals can be defined by certain biological indexes instead of answering the questionnaire,and to explore the possibility of discriminating nine TCM constitutions from each other simultaneously using biological indexes.Methods:Blood and urine samples from 152 individuals with nine TCM constitutions were collected,and the related biological indexes were analyzed combining ANOVA,multiple comparison,discriminant analysis,and support vector machine.Results:We found that 4 out of 24 blood routine indexes,7 out of 10 urine routine indexes,and 12 out of 32 biochemical indexes showed differences among the constitutions.High-sensitivity C-reactive protein,apolipoprotein A1,and alkaline phosphatase were potential candidates for screening out individuals with unbalanced constitutions.Combining uric acid,high-density lipoprotein,apolipoprotein A1,creatine kinase,total protein,aspartate aminotransferase,total bile acid,dehydrogenase,sodium,and calcium levels had the potential to directly distinguish the nine TCM constitutions from each other.Among these indexes,the highest ratio of discriminant analysis between two constitutions was 95.5%,while the lowest was 66.1%.Conclusion:Our results suggest that some biochemical and urine indexes are related to various TCM constitutions,and thus they have the potential to be used for TCM constitution classification.
基金Project supported by the National Key Research and Development Program of China (Grant Nos.2020YFA0710100 and 2023YFA1407100)the National Natural Science Foundation of China (Grant Nos.92050102 and 12374410)+2 种基金the Jiangxi Provincial Natural Science Foundation (Grant No.20224ACB201005)the Fundamental Research Funds for the Central Universities (Grant Nos.20720230102 and 20720220033)China Scholarship Council (Grant No.202206310009)。
文摘The fast and convenient demultiplex of optical vortex(OV) mode is crucial for its further application. We propose a novel approach that combines classic Young's doublet with an OV source to effectively identify the OV mode through the analysis of interference patterns. The interference patterns of the OV source incident on the double slits can be perfectly illustrated by using both the classical double-slit interference method and the Huygens–Fresnel principle. The interference fringes will twist along the negative or positive direction of x axis when topological charge(TC)l>0 or l<0, and the degree of the movement varies with the TC, allowing for a quantitative display of the OV characteristics through the interference patterns. Additionally, we deduce analytically that the zeroth-order interference fringe has a linear relationship with the TC and the vertical position. These findings highlight the ability to identify the OV mode by analyzing the interference patterns produced by Young's doublet.
基金Supported by the National Natural Science Foundation of China(Grant No.11874311).
文摘We propose multi-core conformal lenses by combining conformal transformation optics with absolute instruments.Depending on the cores and incident angles,the conformal lenses have tunable functionalities like focusing,reflection,and transparency,thereby providing a feasible general method for designing multi-functional devices.
基金This study was supported by the National Key Research and Development Project(Ministry of Science and Technology,China,grant ID:2019YFC1710104)National Natural Science Foundation of China(grant IDs:8200152760 and 81430099)Research Program from Beijing University of Chinese Medicine(grant IDs:1000041510049,2019-JYB-TD013 and BUCM-2019-JCRC006).
文摘Objective:To clarify the structural and functional characteristics of the gut microbiota in individuals with qi stagnation constitution(QSC)and identify the potential biomarkers related to QSC.Methods:This cross-sectional study involved individuals with QSC and balanced constitution(BC)confirmed by TCM clinicians.The clinical features were recorded,and fecal samples were collected for 16S rDNA sequencing.The structure of the fecal-associated microbiome(FAM)was described by the alpha-diversity indexes,beta-distances,and relative abundances of dominant taxa.The differences in FAM distribution were analyzed by the Wilcoxon rank-sum test,MetagenomeSeq,and LEfSe analysis.The 16S rDNA gene sequences were assigned to the KEGG dataset to predict the functional information of bacterial metabolic pathways by using PICRUSt.Differences in functional pathways between groups were assessed with the Wilcoxon rank-sum test.The ROC curve based on specific operational taxonomic units(OTUs)was constructed,and the AUC was calculated.Results:Twenty-two individuals with BC and 8 with QSC were recruited.Significant differences between the two groups were found in body mass index,health status,and low-density lipoprotein,etc.There was no significant difference in the alpha-diversity index.PCoA showed no evident clustering of bacterial communities according to constitutions.Bacteroidaceae,Lachnospiraceae,Ruminococcaceae,and Prevotellaceae were the four common bacteria with high abundances.Notably,MetagenomeSeq,LEfSe analysis,and the Wilcoxon rank-sum test identified significantly different distributions of 66,42,and 36 OTUs,respectively.Predictive function analysis showed that 13 metabolic pathways were significantly differentially distributed,including those related to fatty acid synthesis.Five specific OTUs were selected as potential biomarkers of a QSC,and the AUC was 0.94.Conclusion:Individuals with QSC have unique FAM structure and related functional characteristics.Five specific OTUs were identified to serve as potentially effective biomarkers related to QSC.
文摘The publisher regrets that the Supporting Information of this paper was wrongly uploaded during production.The publisher would like to apologize to the authors and for any inconvenience caused.
基金supported by the National Natural Science Foundation of China(grant No.52322405)the National Key R&D Program of China(grant No.2022YFC2905900)+2 种基金the Central Guidance on Local Science and Technology Development Fund of Xinjiang Province(grant No.ZYYD2024CG08)the Fundamental Research Funds for Central Universities(grant No.2023ZDPY07)Research program of Jiangsu Key Laboratory for Clean Utilization of carbon resources(grant No.BM2024007).
文摘Efficient dry beneficiation of low-grade oil shale requires precise regulation of bed density in high-density gas-solid fluidized beds.This study develops a ternary dense-medium system comprising ferrosilicon powder,magnetite powder and oil shale particles,and investigates the coupling between medium composition,hydrodynamics and machine-learning-assisted density prediction.The results demonstrated that the ternary density regulation strategy significantly enhances fluidization uniformity and separation efficiency in the dry dense-medium fluidized bed.When the oil-shale mass fraction increases from 0%to 20%,the critical fluidization velocity rises from 12.54 to 14.08 cm/s,while the bed expansion ratio grows from 5.19%to 8.83%.Compared with the conventional binary medium,the ternary system lowers the mean bed density from 2.567 to 2.382 g cm^(-3) and achieves the minimum density fluctuation(standard deviation,SD=0.097)at an optimal oil-shale mass fraction of 8%.A back-propagation neural network optimized by a genetic algorithm(GA-BP)using seven process features predicts bed density with correlation coefficient R=0.979 and root-mean-square error(RMSE)of 0.049 on 167 test samples—an 18%error reduction over the conventional BP model.The proposed ternary medium strategy and GA-BP predictor therefore offer a robust framework for stable,energy-efficient dry separationofoil shale.
基金supported by the National Natural Science Foundation of China(grant No.52322405)the National Key R&D Program of China(grant No.2022YFC2905900)+2 种基金the Central Guidance on Local Science and Technology Development Fund of Xinjiang(grant No.ZYYD2024CG08)the Fundamental Research Funds for Central Universities(grant No.2023ZDPY07)Research Program of Jiangsu Key Laboratory for Clean Utilization of Carbon Resources(grant No.BM2024007).
文摘Efficient dry separation is essential for utilizing low-grade oil shale.This study developed a ternary high-density gas–solid fluidized bed system using ferrosilicon powder,magnetite powder,and D-class oil shale particles,focusing on the impact of apparent viscosity on particle settling.Results showed that viscosity was influenced by medium composition,particle size,and flow structure.In the binary system of B−silicon and B+magnetite,minimum viscosity(0.782 Pa s)was reached at a 40%ferrosilicon ratio.In the ternary system,viscosity increased nonlinearly with oil shale content,with 8%being the critical threshold where fluidization stability declined.Gas velocity significantly affected viscosity distribution,with moderate increases improving flow uniformity and reducing viscosity by 32%–40%.However,excessive velocity caused bubble coalescence and increased viscosity fluctuations,with standard deviation rising from 0.0065 to 0.0191 Pa s.Sedimentation tests showed that the middle bed region provided optimal separation at low gas velocity,while higher velocities shifted separation to the upper region.When gas velocity exceeds 0.45 m/s,the best separation efficiency is achieved.This study clarifies the relationship between viscosity and separation performance,providing guidance for optimizing dry oil shale separation.
文摘Though an accurate discretization approach for gas flow dynamics, the method of characteristics (MOC) is liable to instability for inappropriate step sizes. This letter addresses the numerical stability limitation of MOC, in the context of lEGS's optimal scheduling. Specifically, the proposed method enables flexible temporal step sizes without sacrificing accuracy, significantly reducing non-convergence due to numerical oscillations. The effectiveness of the proposed method is validated through case studies in different simulation settings.
