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Particuology 2019年第5期17卷 22-29页

作者： M. Hafizur Rahman Lius Daniel Ujash Shah Xiaotao Bi John R. Grace c.jim lim Fluidization Research centre Department of Chemical & Biological Engineering University of British Columbia 2360 East Mall Vancouver British Columbia V6T1Z3 Canada

Operation of a dual fluidized bed, consisting of a riser as combustor and bubbling bed as gasifier, for synthesis gas production from a solid fuel requires determination of the solids circulation rate and char transfer rate. The performance relies on supplying sufficient heat from the combustor to the gasifier by circulation of solids between these two reactors. The flow rate of char is required to track the heat generated in the combustor, which supports endothermic reactions in the gasifier. Direct measurement of these two critical parameters is difficult, with the number of reported techniques capable of working at high temperatures extremely small. An indirect method was developed, using mass and energy balances over the entire system and individual reactors, to estimate the solids circulation rate and char transfer rate. There was general agreement between heat losses estimated from energy-balance calculations and from direct measurement of the outer reactor surface temperature. Under typical gasification conditions, the solids circulation fluxes were estimated to be 45.2 and 55.6 kg/(m^2 s) in two independent tests, which were in good agreement with values obtained using a thermal tracer;char transfer rates were calculated to be 1.2 and 0.6 kg/h, which were in reasonable agreement with average biomass feed rates. This method can be applied to dual gasification systems at any temperature or flow rate.

关键词： Solids circulation rate char transfer rate Pilot-plant gasifier Dual fluidized bed Mass and energy balance

Single-cell and spatial omics:exploring hypothalamic heterogeneity

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Neural Regeneration Research 2025年第6期20卷 1525-1540页

作者： Muhammad Junaid Eun Jeong Lee Su Bin lim Department of Biochemistry&Molecular Biology Ajou University School of MedicineSuwonSouth Korea Department of Biomedical Sciences Graduate School of Ajou UniversitySuwonSouth Korea Department of Brain Science Ajou University School of MedicineSuwonSouth Korea

Elucidating the complex dynamic cellular organization in the hypothalamus is critical for understanding its role in coordinating fundamental body functions. Over the past decade, single-cell and spatial omics technologies have significantly evolved, overcoming initial technical challenges in capturing and analyzing individual cells. These high-throughput omics technologies now offer a remarkable opportunity to comprehend the complex spatiotemporal patterns of transcriptional diversity and cell-type characteristics across the entire hypothalamus. current single-cell and single-nucleus RNA sequencing methods comprehensively quantify gene expression by exploring distinct phenotypes across various subregions of the hypothalamus. However, single-cell/single-nucleus RNA sequencing requires isolating the cell/nuclei from the tissue, potentially resulting in the loss of spatial information concerning neuronal networks. Spatial transcriptomics methods, by bypassing the cell dissociation, can elucidate the intricate spatial organization of neural networks through their imaging and sequencing technologies. In this review, we highlight the applicative value of single-cell and spatial transcriptomics in exploring the complex molecular-genetic diversity of hypothalamic cell types, driven by recent high-throughput achievements.

关键词： cellular diversity hypothalamus multi-omics single-cell transcriptomics spatial transcriptomics

Processing of Aerosol Particles in convective cumulus clouds:cases Study in the Mexican East Pacific

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Advances in Atmospheric Sciences 2010年第6期27卷 1331-1343页

作者： José c.jimNEZ-EScALONA Oscar PERALTA ESIME UP Ticomán National Polytechnic Institute chemistry Faculty National Autonomous University of MexicoCiudad Universitaria

In the Mexican Intertropical convergence Zone, particle size distributions within 500 m of cloud boundaries at altitudes of 1000, 2500, and 4200 m, were compared against size distributions at the same levels but 1500 m away from the clouds. The differences in the distributions near and far from the cloud are related to processes that may change particle properties inside the cloud. chemical changes in the aerosols are deduced from the particles＇ refractive index, as derived from comparisons with the scattering coeflcient measured by a nephelometer. An analysis of ten cloud systems indicates that vertical transport of cloud base aerosol followed by entrainment/detrainment is the cloud processing signature most frequently observed in the comparisons （65%）. changes in the chemical composition are observed in approximately 20% of the cases and another 20% of the cases showed removal by precipitation. About 5% of the comparisons showed clear evidence of changes by coalescence. The principal effect of these cloud-processed aerosols is observed in the increase of optical depth in the layer from 30 m to 4200 m in the near-cloud regions, in comparison with the atmosphere further from clouds.

关键词： cloud processing cloud interaction scattering redistribution entrainment

Digital thermal monitoring of the Amazon forest:an intercomparison of satellite and reanalysis products

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International Journal of Digital Earth 2016年第5期9卷 477-498页

作者： Juan c.jiménez-Muñoz cristian Mattar José A.Sobrino Yadvinder Malhi Global change Unit Image Processing LaboratoryUniversity of ValenciaPaternaSpain Laboratory for Analysis of the Biosphere Department of Environmental Sciences and Renewable Natural ResourcesUniversity of ChileLa PintanaChile School of Geography and Environment Environmental Change InstituteUniversity of OxfordOxfordUK

Remote sensing and climate digital products have become increasingly available in recent *** to these products has favored a variety of Digital Earth studies,such as the analysis of the impact of global warming over different *** study of the Amazon forest response to drought has recently received particular attention from the scientific community due to the occurrence of extreme droughts and anomalous warming over the last *** paper focuses on the differences observed between surface thermal anomalies obtained from remote sensing moderate resolution imaging spectroradiometer(MODIS)and climatic(ERA-Interim)monthly products over the Amazon *** a few exceptions,results show that the spatial pattern of standardized anomalies is similar for both *** terms of absolute anomalies,the differences between the two products show a bias near to zero with a standard deviation of around 0.2 K,although the differences can be up to 1 K over particular regions and *** this general agreement,the proper filtering of MODIS daily values in order to construct a new monthly product showed a dramatic reduction in the number of reliable pixels during the rainy season,while for the dry season this reduction is only seen in Northern Amazonia.

关键词： Thermal anomalies Amazon forest MODIS ERA interim thermal Amazonia

Evaluation of Terra/MODIS atmospheric profiles product(MOD07)over the Iberian Peninsula:a comparison with radiosonde stations

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International Journal of Digital Earth 2015年第10期8卷 771-783页

作者： JoséA.Sobrino Juan c.jiménez-Muñoz cristian Mattar Guillem Sòria Global change Unit–Image Processing Laboratory University of ValenciaValenciaSpain Laboratory for Analysis of the Biosphere Universidad de ChileSantiagoChile

Remote sensing techniques are a useful tool for continuous observation of the Earth at global ***,products derived from remote sensing data require a rigorous validation using in situ *** Resolution Imaging Spectroradiometer(MODIS)is not really a sounding instrument,but it does have 16 infrared bands(bands 20-36 covering the spectral range from 3μm to 14μm)that allow the retrieval of temperature and moisture profiles as well as total column integrated *** this paper we show the results obtained in the evaluation of MOD07 daytime and nighttime products over the Iberian Peninsula during the decade from 2000 to 2010 using nine radiosonde *** MODIS limitations in comparison with other sounding instruments,the validation provided satisfactory results,with bias(MOD07 minus radiosonde)cm and a standard deviation of 0.5 cm for the total column water vapor,and bias around 1 K on average with standard deviations between 2 K and 3 K for air temperature at different pressure *** average,bias was positive and below 2 K with standard deviations around 5 K for the dew point temperature *** errors were found in this case for pressure levels higher than 50 hPa.

关键词： MODIS MOD07 atmospheric profiles water vapor air temperature dew point temperature

Biomass torrefaction in a slot-rectangular spouted bed reactor

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Particuology 2019年第1期17卷 154-162页

作者： Ziliang Wang c. jim lim John R. Grace Department of chemical and Biological Engineering. University of British columbia Vancouver. Canada

Sawdust was subjected to torrefaction in a "semi-batch" slot-rectangular spouted bed (SRSB) reactor at temperatures from 240 to 330℃ and biomass feed rates from 220 to 710g/*** spouting of the sawdust was achieved in the slot-rectangular spouted bed,although the pressure drop across the reactor was observed to *** to the biomass feed rate,the temperature had a greater effect on the biomass weight loss and energy *** in temperature were found to promote weight loss of the sawdust while decreasing the energy *** main solid product was the torrefied sawdust,which remained in the SRSB reactor and was captured by a *** ratio of the torrefied biomass removed by the cyclone to the total torrefied biomass increased along with both the feed rate and *** undergoing torrefaction,6.7%-39.2% of the original sawdust mass was lost while 67.4%-98.7% of its energy was *** torrefied sawdust had a higher carbon content but less oxygen,hydrogen and volatiles,along with a greater higher heating value and increased density compared to the raw *** size of the sawdust particles also decreased markedly during the torrefaction process.

关键词： Torrefaction Slot-rectangular spouted bed reactor Temperature Biomass feed rate Torrefied sawdust property

comprehensive molecular characterization to predict immunotherapy response in advanced biliary tract cancer:a phase II trial of pembrolizumab

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Oncology Research 2025年第1期33卷 57-65页

作者： RYUL KIM JOO KYUNG PARK MINSUK KWON MINAE AN JUNG YONG HONG JOON OH PARK SUNG HEE lim SEUNG TAE KIM Division of Hematology-Oncology Department of MedicineSamsung Medical CenterSungkyunkwan University School of MedicineSeoulKorea Division of Gastroenterology Department of MedicineSamsung Medical CenterSungkyunkwan University School of MedicineSeoulKorea Department of Hematology-Oncology Ajou University School of MedicineSuwon-siGyeonggi-doKorea Samsung Advanced Institute of Health Science and Technology Sungkyunkwan University School of MedicineSeoulKorea

Background:Immune checkpoint inhibitors(IcIs)are effective in a subset of patients with metastatic solid ***,the patients who would benefit most from IcIs in biliary tract cancer(BTc)are still *** and methods:We molecularly characterized tissues and blood from 32 patients with metastatic BTc treated with the IcI pembrolizumab as second-line ***:All patients had microsatellite stable(MSS)type *** of the 32 patients achieved partial response(PR),with an objective response rate(ORR)of 9.4%(95%confidence interval[cI],2.0–25.2)and nine showed stable disease(SD),exhibiting a disease control rate(DcR)of 37.5%(95%cI,21.1–56.3).For the 31 patients who had access to PD-1 ligand 1(PD-L1)combined positive score(cPS)testing(cut-off value≥1%),the ORR was not different between those who had PD-L1-positive(PD-L1+;1/11,9.1%)and PDL1-(2/20,10.0%)tumors(p=1.000).The tumor mutational burden(TMB)of PD-L1+BTc was comparable to that of PD-L1-BTc(p=0.630).TMB and any exonic somatic mutations were also not predictive of pembrolizumab *** analysis of blood and tumor samples demonstrated a relatively high natural killer(NK)cell proportion in the peripheral blood before pembrolizumab treatment in patients who achieved tumor ***,the tumors of these patients presented high enrichment scores for NK cells,antitumor cytokines,and Th1 signatures,and a low enrichment score for cancer-associated ***:This study shows the molecular characteristics associated with the efficacy of pembrolizumab in BTc of the MSS type.

关键词： Pembrolizumab Whole-exome sequencing Whole-transcriptome sequencing Biliary tract cancer

Effects of the mass and volume shrinkage of ground chip and pellet particles on drying rates

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Particuology 2018年第3期16卷 1-9页

作者： Hamid Rezaei Shahab Sokhansaj c. jim lim Anthony Lau Xiaotao Bi chemical and Biological Engineering Department University of British Columbia Vancouver BC V6T 1Z3 Canada Environmental Science Division Oak Ridge National Laboratory Oak Ridge TN 37381 USA

The effects of varying the mass and volume of ground chip and pellet particles on the particle drying rate were analyzed. Samples of whole pellets and chips were hammer milled using a 3.2 mm screen and the ground chip and pellet particles were found to have similar size distributions, although the pellet particles were denser and more spherical than the chip particles. Prior to drying, water was added to the particles to obtain 0.10, 0.30, 0.50, 0.70, and 0.90 moisture contents （on a dry mass basis）. The moistened particles were subsequently dried in a constant temperature thin layer dryer set at 50,100, 150, or 200 ~c under dry pure nitrogen, dry compressed air, or atmospheric air. The chip and pellet particles exhibited similar degrees of shrinkage, but the pellet particles underwent a greater reduction in their bulk volume during drying. It appears that the more spherical pellet particles are prone to shrinkage in more than one direction, whereas the needle-like chip particle shrink only in one direction. A variable radius first order drying model was found to fit the experimental data better than a fixed radius model.

关键词： Moisture loss Particle density Ground chip Ground pellet Particle shrinkage Bulk shrinkage

Heat transfer in a tapered fluidized bed of biomass particles with pulsed gas flow

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Particuology 2019年第1期17卷 2-14页

作者： Dening Jia Xiaotao Bi c. jim lim Shahab Sokhansanj Atsushi Tsutsumi Department of chemical and Biological Engineering The University of British Columbia2360 East MallVancouverBCV6T 1Z3Canada Environmental Sciences Division Oak Ridge National LaboratoryOak RidgeTN 37831USA collaborative Research center for Energy Engineering Institute of Industrial ScienceThe University of Tokyo4-6-1 KomabaMeguro-kuTokyo 153-8505Japan

Bed-to-surface heat transfer of pure biomass particles in a pulsed fluidized bed with a tapered bottom section was investigated. Three biomass species — Douglas fir, pine, and switchgrass — were studied under various operating conditions. Their heat transfer coefficients were found to be closely associated with hydrodynamics dominated by gas pulsations. A higher superficial gas velocity generally yielded better gas–solid contact and higher heat transfer rates. A moderately increasing pulsation frequency promoted convective heat transfer of particles but also reduced pulsation intensity, leading to undesired flow behaviours such as channelling and partial defluidization. The study of the pulsation duty cycle revealed that, for cohesive particles, a smaller duty cycle was preferred to generate powerful pulsations to break up inter-particle forces. Moreover, a duty cycle increase allowed higher gas throughput as long as a suitable fluidization was maintained. The addition of finer particles to a coarse fraction increased particle mobility, and subsequently heat transfer, which also explained the higher heat transfer coefficients of switchgrass as it contained more fines compared with fir and pine. Experimental results in the tapered bed were also compared with those of non-tapered geometry where a 10%–20% increase in heat transfer was observed.

关键词： Fluidized bed Gas pulsations Tapered column Heat transfer Biomass

Is a nanorod (or nanotube) with a lower Young’s modulus stiffer? Is not Young’s modulus a stiffness indicator?

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 712-724页

作者： lim c. W. Department of Building and construction City University of Hong Kong

It has been a known fact in classical mechanics of materials that Young’s modulus is an indicator of material stiffness and materials with a higher Young’s modulus are stiffer. At the nanoscale, within the scope and under specific circumstances described in this paper, however, a nanorod (or a nanotube) with a smaller Young’s modulus (smaller stress-strain rate) is stiffer. In such a scenario, Young’s modulus is not a stiffness indicator for nanostructures. Furthermore, the nonlocal stress-strain rate is dependent on types of load, boundary conditions and location. This is likely to be one of the many possible reasons why numerous experiments in the past obtained significantly varying values of Young’s modulus for a seemingly identical nanotube, i.e. because the types of loading and/or boundary conditions in the experiments were different, as well as at which point the property was measured. Based on the nonlocal elasticity theory and within the scope of material and geometric linearity, this paper reports the strange and hitherto unrealized effect that a nanorod (or a nanotube) with a lower Young’s modulus (smaller stress-strain rate) indicates smaller extension in tensile analysis. Similarly, it is also predicted that a nanorod (or a nanotube) with a lower Young’s modulus results in smaller bending deflection, higher critical buckling load, higher free vibration frequency and higher wave propagation velocity, which are at all consequences of a stiffer nanostructure.

关键词： nanorod nanotube nonlocal stress nonlocal elasticity stiffness tensile Young’s modulus