The structures of solid dosage forms determine their release behaviors and are critical attributes for the design and evaluation of the solid dosage forms.Here,the 3D structures of doxazosin mesylate sustained-release...The structures of solid dosage forms determine their release behaviors and are critical attributes for the design and evaluation of the solid dosage forms.Here,the 3D structures of doxazosin mesylate sustained-release tablets were parallelly assessed by micro-computed tomography(micro-CT).There were no significant differences observed in the release profiles between the RLD and the generic formulation in the conventional dissolution,but the generic preparation released slightly faster in media with ethanol during an alcohol-induced dose-dumping test.With their 3D structures obtained via micro-CT determination,the unique release behaviors of both RLD and the generic were investigated to reveal the effects of internal fine structure on the release kinetics.The structural parameters for both preparations were similar in conventional dissolution test,while the dissolutions in ethanol media showed some distinctions between RLD and generic preparations due to their static and dynamic structures.Furthermore,the findings revealed that the presence of ethanol accelerated dissolution and induced changes in internal structure of both RLD and generic preparations.Moreover,structure parameters like volume and area of outer contour,remaining solid volume and cavity volumewere not equivalent between the two formulations in 40%ethanol.In conclusion,the structure data obtained from this study provided valuable insights into the diverse release behaviors observed in various modified-release formulations in drug development and quality control.展开更多
Micro-computed tomography (MCT) encompasses two primary scanning options: ex-vivo and in-vivo imaging. Ex-vivo scanning involves the examination of extracted teeth or dental specimens, allowing for detailed analyses o...Micro-computed tomography (MCT) encompasses two primary scanning options: ex-vivo and in-vivo imaging. Ex-vivo scanning involves the examination of extracted teeth or dental specimens, allowing for detailed analyses of the microarchitecture of mineralized tissue. By analyzing the microarchitecture of dental tissues, MCT can provide valuable information about bone density, porosity, and microstructural changes, contributing to a better understanding of disease progression and treatment outcomes. Moreover, MCT facilitates the quantification of dental parameters, such as bone volume, trabecular thickness, and connectivity density, which are crucial for evaluating the efficacy of dental interventions. This present study aims to comprehensively review and explore the applications of MCT in dentistry and highlight its potential in advancing research and clinical practice. The results depicted that the quantitative approach of MCT enhances the precision and reliability of dental research. Researchers and clinicians can make evidence-based decisions regarding treatment strategies and patient management, relying on quantifiable data provided by MCT. The applications of MCT in dentistry extend beyond research, with potential clinical implications in fields such as dental implantology and endodontics. MCT is expected to play an increasingly significant role in enhancing our understanding of dental pathologies, improving treatment outcomes, and ultimately, benefiting patient care in the field of dentistry.展开更多
Exo-atmospheric vehicles are constrained by limited maneuverability,which leads to the contradiction between evasive maneuver and precision strike.To address the problem of Integrated Evasion and Impact(IEI)decision u...Exo-atmospheric vehicles are constrained by limited maneuverability,which leads to the contradiction between evasive maneuver and precision strike.To address the problem of Integrated Evasion and Impact(IEI)decision under multi-constraint conditions,a hierarchical intelligent decision-making method based on Deep Reinforcement Learning(DRL)was proposed.First,an intelligent decision-making framework of“DRL evasion decision”+“impact prediction guidance decision”was established:it takes the impact point deviation correction ability as the constraint and the maximum miss distance as the objective,and effectively solves the problem of poor decisionmaking effect caused by the large IEI decision space.Second,to solve the sparse reward problem faced by evasion decision-making,a hierarchical decision-making method consisting of maneuver timing decision and maneuver duration decision was proposed,and the corresponding Markov Decision Process(MDP)was designed.A detailed simulation experiment was designed to analyze the advantages and computational complexity of the proposed method.Simulation results show that the proposed model has good performance and low computational resource requirement.The minimum miss distance is 21.3 m under the condition of guaranteeing the impact point accuracy,and the single decision-making time is 4.086 ms on an STM32F407 single-chip microcomputer,which has engineering application value.展开更多
Cichlid fishes are a textbook example for adaptive radiations,since they diversified into several hundred highly specialized species in each of three great East African lakes.Even scale-eating,an extremely specialized...Cichlid fishes are a textbook example for adaptive radiations,since they diversified into several hundred highly specialized species in each of three great East African lakes.Even scale-eating,an extremely specialized feeding mode,evolved independently multiple times in these radiations and in Lake Tanganyika alone,six endemic scale-eating species occupy this extremely specialized ecological niche.Perissodus microlepis went a step further,by evolving bilaterally asymmetrical heads with an intra-specific polymorphism where left-and right-headed morphs predominantly scrape scales from the opposite sides of their prey.While the bilateral asymmetry of scale-eating cichlids has been known,exactly which craniofacial features explain the laterality of the heads remained unclear.Here we aimed,by utilizing micro-computed tomography(μCT),to resolve this issue of how bilateral symmetry in the skeletal structure is broken in scale-eating Perissodus.Our 3D geometric morphometrics analysis clearly separated and identified the two groups of either left-or right-headed fish.In addition,we observed consistent asymmetric volume changes in the premaxilla,maxilla,and mandible of the craniofacial structures,where left-headed fish have larger jaw elements on the right side,and vice versa.The bimodality implies that the effect sizes of environmental factors might be minor while genetics might be responsible to a larger extent for the asymmetry observed in their head morphology.High-speed video analyses of attacks by asymmetrical morphotypes revealed that they utilize their asymmetrical mouth protrusion,as well as lateralized behavior,to re-orientate the gape towards the preferred side of their prey fish to more efficiently scrape scales.展开更多
BACKGROUND Safety and efficacy of intravascular ultrasound(IVUS)guidance in percutaneous coronary intervention(PCI)has been consistently shown in recent trials.However,prospective data on the clinical effects of IVUS ...BACKGROUND Safety and efficacy of intravascular ultrasound(IVUS)guidance in percutaneous coronary intervention(PCI)has been consistently shown in recent trials.However,prospective data on the clinical effects of IVUS usage in primary PCI are still warranted.The ULTRA-STEMI trial is a prospective investigator-initiated observational single-center cohort trial aiming to enroll 80 patients with STEMI.AIM To investigate the outcomes of patients with STEMI undergoing IVUS-guided PCI and correlate derived IVUS measurements with clinical,procedural,imaging and follow-up outcomes of interest.METHODS Study participants will undergo primary PCI as per standardized procedures.IVUS pullbacks will be performed pre-intervention,post-lesion preparation,postintervention and post-optimization using a 20 MHz digital IVUS(Eagle Eye Platinum,Philips).Manual thrombus aspiration will be performed in cases of high thrombus burden.The aspirated thrombi will be scanned with micro-computed tomography to extract volumetric measurements of the aspirated thrombotic burden.Moreover,angiographic,peri-procedural and 3-year follow-up data will be gathered.Co-primary endpoints will be cardiovascular mortality and target vessel failure,defined as the composite of:Cardiovascular mortality,target vessel myocardial infarction and/or clinically driven target vessel revascularization.RESULTS The results of the study are expected by the third quarter of 2029.CONCLUSION The ULTRA-STEMI trial will add to the existing literature the clinical,angiographic,micro-computed tomography and follow-up outcomes of IVUS-guided PCI in 80 patients presenting with STEMI.展开更多
The accumulation of soil organic carbon(SOC)and total nitrogen(TN)is easily accomplished by returning crop straw,which strongly affects the formation and pore structure of aggregates,especially in black soil.We return...The accumulation of soil organic carbon(SOC)and total nitrogen(TN)is easily accomplished by returning crop straw,which strongly affects the formation and pore structure of aggregates,especially in black soil.We returned maize straw at different rates(6,000,9,000,12,000 and 15,000 kg ha^(-1))for nine years to investigate its influence on the SOC and TN contents in the SOC fractions of aggregates by combining size and density fractionation.Their subsequent influences on pore morphology and size distribution characteristics were examined using X-ray microcomputed tomography scanning(μCT).The results showed that returning straw significantly increased the contents of C and N in the SOC fractions of aggregates,especially at the return rates of 12,000 and 15,000 kg ha^(-1),which in turn promoted aggregate formation and stability,and ultimately amended pore structure.The pore size>100μm,porosity(>2μm),and morphological characteristics(anisotropy,circularity,connectivity and fractal dimension)significantly increased,but the total number of pores significantly decreased(P<0.05).Our results indicated that the amendment of the pore morphology and size distribution of soil aggregates was primarily controlled by the higher contents of C and N in the density fractions of aggregates,rather than in the aggregate sizes.Furthermore,this pore network reconfiguration favored the storage of C and N simultaneously.The findings of this study offer valuable new insights into the relationships between C and N storage and the pore characteristics in soil aggregates under straw return.展开更多
As a typical sedimentary soft rock,mudstone has the characteristics of being easily softened and disintegrated under the effect of wetting and drying(WD).The first cycle of WD plays an important role in the entire WD ...As a typical sedimentary soft rock,mudstone has the characteristics of being easily softened and disintegrated under the effect of wetting and drying(WD).The first cycle of WD plays an important role in the entire WD cycles.X-ray micro-computed tomography(micro-CT)was used as a non-destructive tool to quantitatively analyze microstructural changes of the mudstone due to the first cycle of WD.The test results show that WD leads to an increase of pore volume and pore connectivity in the mudstone.The porosity and fractal dimension of each slice of mudstone not only increase in value,but also in fluctuation amplitude.The pattern of variation in the frequency distribution of the equivalent radii of connected,isolated pores and pore throats in mudstone under WD effect satisfies the Gaussian distribution.Under the effect of WD,pores and pore throats with relatively small sizes increase the most.The sphericity of the pores in mudstones is positively correlated with the pore radius.The WD effect transforms the originally angular and flat pores into round and regular pores.This paper can provide a reference for the study of the deterioration and catastrophic mechanisms of mudstone under wetting and drying cycles.展开更多
Three-dimensional printing(3DP)offers valuable insight into the characterization of natural rocks and the verification of theoretical models due to its high reproducibility and accurate replication of complex defects ...Three-dimensional printing(3DP)offers valuable insight into the characterization of natural rocks and the verification of theoretical models due to its high reproducibility and accurate replication of complex defects such as cracks and pores.In this study,3DP gypsum samples with different printing directions were subjected to a series of uniaxial compression tests with in situ micro-computed tomography(micro-CT)scanning to quantitatively investigate their mechanical anisotropic properties and damage evolution characteristics.Based on the two-dimensional(2D)CT images obtained at different scanning steps,a novel void ratio variable was derived using the mean value and variance of CT intensity.Additionally,a constitutive model was formulated incorporating the proposed damage variable,utilizing the void ratio variable.The crack evolution and crack morphology of 3DP gypsum samples were obtained and analyzed using the 3D models reconstructed from the CT images.The results indicate that 3DP gypsum samples exhibit mechanical anisotropic characteristics similar to those found in naturally sedimentary rocks.The mechanical anisotropy is attributed to the bedding planes formed between adjacent layers and pillar-like structures along the printing direction formed by CaSO_(4)·2H_(2)O crystals of needle-like morphology.The mean gray intensity of the voids has a positive linear relationship with the threshold value,while the CT variance and void ratio have concave and convex relationships,respectively.The constitutive model can effectively match the stress–strain curves obtained from uniaxial compression experiments.This study provides comprehensive explanations of the failure modes and anisotropic mechanisms of 3DP gypsum samples,which is important for characterizing and understanding the failure mechanism and microstructural evolution of 3DP rocks when modeling natural rock behavior.展开更多
Microstructure of shale formation is the key to understanding its petrophysical and chemical properties.Optical microscopy, scanning electron microscopy and micro-computed tomography(μ-CT) have been combined for char...Microstructure of shale formation is the key to understanding its petrophysical and chemical properties.Optical microscopy, scanning electron microscopy and micro-computed tomography(μ-CT) have been combined for characterization of microstructure of Longmaxi(LMX)shale from Shizhu area, Sichan Basin. The results indicate that laminated LMX shale consists of mineral matrix-rich layers and organic matter(OM)-rich layers at micrometer scale in two and three dimensions. Mineral matrix layers,mainly consisting of interparticle pores and intraplatelet pores, are approximately parallel to the bedding plane.Pyrite-rich layer, mainly containing intercrystalline pores,shows a strong preferred orientation parallel to the bedding plane. OM-rich layer, mainly containing OM pores, seems to be discontinuous. In addition, intercrystalline pores are enriched in some layers, while OM pores are distributed irregularly in matrix layers. This vertical heterogeneity of pore microscopic structures in LMX shale is of great importance to understand its petrophysical and chemical properties.展开更多
This study aimed to utilize micro-computed tomography （micro-CT） analysis to compare new bone formation in rat calvarial defects using chitosan/fibroin-hydroxyapatite （CFB-HAP） or collagen （Bio-Gide） membranes. ...This study aimed to utilize micro-computed tomography （micro-CT） analysis to compare new bone formation in rat calvarial defects using chitosan/fibroin-hydroxyapatite （CFB-HAP） or collagen （Bio-Gide） membranes. Fifty-four （54） rats were studied. A circular bony defect （8 mm diameter） was formed in the centre of the calvaria using a trephine bur. The CFB-HAP membrane was prepared by thermally induced phase separation. In the experimental group （n= 18）, the CFB-HAP membrane was used to cover the bony defect, and in the control group （n= 18）, a resorbable collagen membrane （Bio-Gide） was used. In the negative control group （n= 18）, no membrane was used. In each group, six animals were euthanized at 2, 4 and 8 weeks after surgery. The specimens were then analysed using micro-CT. There were significant differences in bone volume （BV） and bone mineral density （BMD） （P〈O.05） between the negative control group and the membrane groups. However, there were no significant differences between the CFB-HAP group and the collagen group. We concluded that the CFB-HAP membrane has significant potential as a guided bone regeneration （GBR） membrane.展开更多
Length and concise structure of fuzzy logic reasoning program and its real-time reasoning characteris-tic have their effect on the performance of a digital single-chip fuzzy controller. The control effect of a digital...Length and concise structure of fuzzy logic reasoning program and its real-time reasoning characteris-tic have their effect on the performance of a digital single-chip fuzzy controller. The control effect of a digitalfuzzy controller based on looking up fuzzy control responding table is only relative to the table and not relative tothe fuzzy control rules in the practical control process. Aiming at above problem and having combined fuzzy log-ic reasoning with digital operational characteristics of a single-chip microcomputer, functioning-fuzzy-subset in-ference (FFSI) in binary, in which triangle membership functions of error and error-in-change are all represen-ted in binary and singleton membership functions of control variable is binary too, has been introduced. The cir-cuit principle plans of a single-chip fuzzy controller have been introduced for development of its hardware, andthe primary program structure, fuzzy logic reasoning subroutine, serial communication subroutine with PC andreliability design of the fuzzy controller are all discussed in detail. The control of indoor temperature by a fuzzycontroller has been conducted using a testing-room thermodynamic system. Research results show that the FFSIin binary can exercise a concise fuzzy control in a single-chip fuzzy controller, and the fuzzy controller is there-fore reliable and possesses a high performance-price ratio.展开更多
We successfully obtained 3D skeletal images of Hyla suweonensis, employing a nondestructive method by applying appropriate anesthesia and limiting the radiation dose. H. suweonensis is a tree frog endemic to Korea and...We successfully obtained 3D skeletal images of Hyla suweonensis, employing a nondestructive method by applying appropriate anesthesia and limiting the radiation dose. H. suweonensis is a tree frog endemic to Korea and is on the list of endangered species. Previous studies have employed caliper-based measurements and two-dimensional （2D） X-ray imaging for anatomical analyses of the skeletal system or bone types of H. suweonensis. In this work we reconstructed three-dimensional （3D） skeletal images of H. suweonensis, utilizing a nondestructive micro-computed tomography （micro-CT） with a short scan and low radiation dose （i.e. 4 min and 0.16 Gy）. Importantly, our approach can be applied to the imaging of 3D skeletal systems of other endangered frog species, allowing both versatile and high contrast images of anatomical structures without causing any significant damages to the living animal.展开更多
This paper is aimed at the actual conditions of disaster caused by gas in small and medium-sized coal mines. A new gas concentration monitoring system for coal mines is developed on the basis of gas-sensing detection ...This paper is aimed at the actual conditions of disaster caused by gas in small and medium-sized coal mines. A new gas concentration monitoring system for coal mines is developed on the basis of gas-sensing detection and single-chip control. The monitoring system uses the tin oxide as the main material of N-type semiconductor gas sensors, be- cause it has good sensitive characteristics for the flammable and explosive gas （ such as methane, carbon monoxide）. The QM-N5-semiconductor gas sensor is adopted to detect the output values of the resistance under the different gas con- centrations. The system, designedly, takes the AT89C51 digital chip as the core of the circuit processing hardware structure to analyze and judge the input values of the resistance, and then achieve the control and alarm for going beyond the limit of gas concentration. The gas concentration monitoring system has man）, advantages including simple in struc- ture, fast response time, stable performance and low cost. Thus, it can be widely used to monitor gas concentration and provide early wamings in small and medium-sized coal mines.展开更多
AIM: To explore the potential of contrast-enhanced computed tomography(CECT) using Exi Tron nano6000 for assessment of liver lesions in mouse models.METHODS: Three mouse models of liver lesions were used: bile duct li...AIM: To explore the potential of contrast-enhanced computed tomography(CECT) using Exi Tron nano6000 for assessment of liver lesions in mouse models.METHODS: Three mouse models of liver lesions were used: bile duct ligation(BDL),lipopolysaccharide(LPS)/D-galactosamine(D-Gal N),and alcohol.After injection with the contrast agent Exi Tron nano6000,the mice were scanned with micro-CT.Liver lesions were evaluated using CECT images,hematoxylin and eosin staining,and serum aminotransferase levels.Macrophage distribution in the injury models was shown by immunohistochemical staining of CD68.The in vitro studies measured the densities of RAW264.7 under different conditions by CECT.RESULTS: In the in vitro studies,CECT provided specific and strong contrast enhancement of liver in mice.CECT could present heterogeneous images anddensities of injured livers induced by BDL,LPS/D-Gal N,and alcohol.The liver histology and immunochemistry of CD68 demonstrated that both dilated biliary tracts and necrosis in the injured livers could lead to the heterogeneous distribution of macrophages.The in vitro study showed that the RAW264.7 cell masses had higher densities after LPS activation.CONCLUSION: Micro-CT with the contrast agent Exi Tron nano6000 is feasible for detecting various liver lesions by emphasizing the heterogeneous textures and densities of CECT images.展开更多
In order to study the microstructure characteristics of normal lunate bones, eight fresh cadaver normal lunates were scanned with micro-computed tomography. High-resolution images of the micro-structure of normal luna...In order to study the microstructure characteristics of normal lunate bones, eight fresh cadaver normal lunates were scanned with micro-computed tomography. High-resolution images of the micro-structure of normal lunates were obtained and we analyzed the nutrient foramina. Then nine regions of interest(ROI) were chosen in the central sagittal plane so that we could obtain the parameters of trabecular bones of ROIs. The distal lamellar-like compact structure had statistically significant differences when it was compared with the ROIs in the volar and dorsal ends of the distal cortex. The difference of diameter between the volar and dorsal foramina was significant(P<0.05). However, there was no significant difference regarding the number. The trabecular bones of the volar and dorsal distal ends had lower intensity than those of the distal central subchondral bone plate. The diameters of the nutrient foramina on the volar cortex were larger than those on the dorsal. This research provided more detailed information about microstructure of normal lunate and the nutrient foramina on cortex, and a reference for further study about diseased lunate.展开更多
A single-chip UHF RFID reader transceiver IC has been implemented in 0.18 μm SiGe BiCMOS technology. The chip includes all transceiver blocks as RX/TX RF front-end, RX/TX analog baseband, frequency synthesizer and I2...A single-chip UHF RFID reader transceiver IC has been implemented in 0.18 μm SiGe BiCMOS technology. The chip includes all transceiver blocks as RX/TX RF front-end, RX/TX analog baseband, frequency synthesizer and I2C with fully-compliant China 800/900 MHz RFID draft, ISO/IEC 18000-6C protocol and ETSI 302 208-1 local regulation. The normal mode receiver in the presence of -3 dBm self-jammer achieves -75 dBm 1% PER sensitivity. The linear class-A PA integrated in transmitter has 25 dBm OP1 dB output power for CW. The fully-integrated fractional-N fre-quency synthesizer is designed based on MASH 1-1-1 sigma-delta modulator and 1.8 GHz fundamental frequency LC-VCO for lower in-band and out-of-band phase noise. The measured phase noise is up to -106 dBc/Hz@200 kHz and -131 dBc/Hz@1 MHz offset from center frequency and the integrated RMS jitter from 10 kHz to 10 MHz is less than 1.6 pS. The chip dissipates 330 mA from 3.3 V power supply when transmitting 22.4 dBm CW signal and the PAE of linear PA is up to 26%. The chip die area is 16.8 mm2.展开更多
The aim of this study was to determine whether contrast-enhanced micro-computed tomography can be used for non-invasive imaging of the early-stage changes in the vasculature of tumours that have been treated with phot...The aim of this study was to determine whether contrast-enhanced micro-computed tomography can be used for non-invasive imaging of the early-stage changes in the vasculature of tumours that have been treated with photodynamic therapy (PDT). The subjects used were C3H mice with an RIF-1 tumour implanted subcutaneously and allowed to grow for 3 weeks prior to treatment. The experimental groups were PDT-treated (150 J/cm2 and 50 J/cm2) and control (150 J/cm2 light-only and untreated). The laser light exposure was performed at 15 - 30 minutes after the administration of the photosensitizer (BPD-MA). The contrast-enhanced micro-computed tomography imaging procedure consisted of eight-second scans taking place before treatment and up to 24 hours after treatment. The 150 J/cm2 PDT group showed a significant increase in the ratio of blood volume to tumour volume at 2, 8 and 24 hours after treatment when compared to pre-treatment measurements (p 2 PDT group at 24 hours after treatment. This preliminary study indicates that micro-CT can detect compromised vasculature in tumours treated with high-fluence photodynamic therapy as early as 2 hours post treatment.展开更多
The aim of this study was to identify three-dimensional microstructural changes of trabecular bone with age and gender, using micro-computed tomography. Human trabecular bone from two disease groups, osteoporosis and ...The aim of this study was to identify three-dimensional microstructural changes of trabecular bone with age and gender, using micro-computed tomography. Human trabecular bone from two disease groups, osteoporosis and osteoarthritis was analyzed. A prior analysis of the effects of some procedure variables on the micro-CT results was performed. Preliminary micro-CT scans were performed with three voxel resolutions and two acquisition conditions. On the reconstruction step, the image segmentation was performed with three different threshold values. Samples were collected from patients, with coxarthrosis (osteoarthritis) or fragility fracture (osteoporosis). The specimens of the coxarthrosis group include twenty females and fifteen males, while the fragility fracture group was composed by twenty three females and seven males. The mean age of the population was 69 ± 11 (females) and 67 ± 10 years (males), in the coxarthrosis group, while in the fragility fracture group was 81 ± 6 (females) and 78 ± 6 (males) years. The 30 μm voxel size provided lower percentage difference for the microarchitecture parameters. Acquisition conditions with 160 μA and 60 kV permit the evaluation of all the volume’s sample, with low average values of the coefficients of variation of the microstructural parameters. No statistically significant differences were found between the two diseases groups, neither between genders. However, with aging, there is a decrease of bone volume fraction, trabecular number and fractal dimension, and an increase of structural model index and trabecular separation, for both disease groups and genders. The parameters bone specific surface, trabecular thickness and degree of anisotropy have different behaviors with age, depending on the type of disease. While in coxarthrosis patients, trabecular thickness increases with age, in the fragility fracture group, there is a decrease of trabecular thickness with increasing age. Our findings indicate that disease, age and gender do not provide significant differences in trabecular microstructure. With aging, some parameters exhibit different trends which are possibly related to different mechanisms for different diseases.展开更多
The phase behavior of gas condensate in reservoir formations differs from that in pressure-volume-temperature(PVT)cells because it is influenced by porous media in the reservoir formations.Sandstone was used as a samp...The phase behavior of gas condensate in reservoir formations differs from that in pressure-volume-temperature(PVT)cells because it is influenced by porous media in the reservoir formations.Sandstone was used as a sample to investigate the influence of porous media on the phase behavior of the gas condensate.The pore structure was first analyzed using computed tomography(CT)scanning,digital core technology,and a pore network model.The sandstone core sample was then saturated with gas condensate for the pressure depletion experiment.After each pressure-depletion state was stable,realtime CT scanning was performed on the sample.The scanning results of the sample were reconstructed into three-dimensional grayscale images,and the gas condensate and condensate liquid were segmented based on gray value discrepancy to dynamically characterize the phase behavior of the gas condensate in porous media.Pore network models of the condensate liquid ganglia under different pressures were built to calculate the characteristic parameters,including the average radius,coordination number,and tortuosity,and to analyze the changing mechanism caused by the phase behavior change of the gas condensate.Four types of condensate liquid(clustered,branched,membranous,and droplet ganglia)were then classified by shape factor and Euler number to investigate their morphological changes dynamically and elaborately.The results show that the dew point pressure of the gas condensate in porous media is 12.7 MPa,which is 0.7 MPa higher than 12.0 MPa in PVT cells.The average radius,volume,and coordination number of the condensate liquid ganglia increased when the system pressure was between the dew point pressure(12.7 MPa)and the pressure for the maximum liquid dropout,Pmax(10.0 MPa),and decreased when it was below Pmax.The volume proportion of clustered ganglia was the highest,followed by branched,membranous,and droplet ganglia.This study provides crucial experimental evidence for the phase behavior changing process of gas condensate in porous media during the depletion production of gas condensate reservoirs.展开更多
This study develops low-fat microwaved peanut snacks(LMPS)using partially defatted peanuts(PDP)with different defatting ratios,catering to people’s pursuit of healthy,low-fat cuisine.The effects of defatting treatmen...This study develops low-fat microwaved peanut snacks(LMPS)using partially defatted peanuts(PDP)with different defatting ratios,catering to people’s pursuit of healthy,low-fat cuisine.The effects of defatting treatment on the structural characteristics,texture,color,and nutrient composition of LMPS were comprehensively explored.The structural characteristics of LMPS were characterized using X-ray micro-computed tomography(Micro-CT)and scanning electron microscope(SEM).The results demonstrated that the porosity,pore number,pore volume,brightness,brittleness,protein content,and total sugar content of LMPS all significantly increased(P<0.05)with the increase in the defatting ratio.At the micro level,porous structure,cell wall rupture,and loss of intracellular material could be observed in LMPS after defatting treatments.LMPS made from PDP with a defatting ratio of 64.44%had the highest internal pore structural parameters(porosity 59%,pore number 85.3×10^(5),pore volume 68.23 mm3),the brightest color(L^(*) 78.39±0.39),the best brittleness(3.64±0.21)mm^(–1)),and the best nutrition(high protein content,(34.02±0.38)%;high total sugar content,(17.45±0.59)%;low-fat content,(27.58±0.85)%).The study provides a theoretical basis for the quality improvement of LMPS.展开更多
基金This work was supported by the Key Programfor International Science and Technology Cooperation Projects of China(2020YFE0201700)State Drug Administration key laboratory project(2024HYZX04).
文摘The structures of solid dosage forms determine their release behaviors and are critical attributes for the design and evaluation of the solid dosage forms.Here,the 3D structures of doxazosin mesylate sustained-release tablets were parallelly assessed by micro-computed tomography(micro-CT).There were no significant differences observed in the release profiles between the RLD and the generic formulation in the conventional dissolution,but the generic preparation released slightly faster in media with ethanol during an alcohol-induced dose-dumping test.With their 3D structures obtained via micro-CT determination,the unique release behaviors of both RLD and the generic were investigated to reveal the effects of internal fine structure on the release kinetics.The structural parameters for both preparations were similar in conventional dissolution test,while the dissolutions in ethanol media showed some distinctions between RLD and generic preparations due to their static and dynamic structures.Furthermore,the findings revealed that the presence of ethanol accelerated dissolution and induced changes in internal structure of both RLD and generic preparations.Moreover,structure parameters like volume and area of outer contour,remaining solid volume and cavity volumewere not equivalent between the two formulations in 40%ethanol.In conclusion,the structure data obtained from this study provided valuable insights into the diverse release behaviors observed in various modified-release formulations in drug development and quality control.
文摘Micro-computed tomography (MCT) encompasses two primary scanning options: ex-vivo and in-vivo imaging. Ex-vivo scanning involves the examination of extracted teeth or dental specimens, allowing for detailed analyses of the microarchitecture of mineralized tissue. By analyzing the microarchitecture of dental tissues, MCT can provide valuable information about bone density, porosity, and microstructural changes, contributing to a better understanding of disease progression and treatment outcomes. Moreover, MCT facilitates the quantification of dental parameters, such as bone volume, trabecular thickness, and connectivity density, which are crucial for evaluating the efficacy of dental interventions. This present study aims to comprehensively review and explore the applications of MCT in dentistry and highlight its potential in advancing research and clinical practice. The results depicted that the quantitative approach of MCT enhances the precision and reliability of dental research. Researchers and clinicians can make evidence-based decisions regarding treatment strategies and patient management, relying on quantifiable data provided by MCT. The applications of MCT in dentistry extend beyond research, with potential clinical implications in fields such as dental implantology and endodontics. MCT is expected to play an increasingly significant role in enhancing our understanding of dental pathologies, improving treatment outcomes, and ultimately, benefiting patient care in the field of dentistry.
基金co-supported by the National Natural Science Foundation of China(No.62103432)the China Postdoctoral Science Foundation(No.284881)the Young Talent fund of University Association for Science and Technology in Shaanxi,China(No.20210108)。
文摘Exo-atmospheric vehicles are constrained by limited maneuverability,which leads to the contradiction between evasive maneuver and precision strike.To address the problem of Integrated Evasion and Impact(IEI)decision under multi-constraint conditions,a hierarchical intelligent decision-making method based on Deep Reinforcement Learning(DRL)was proposed.First,an intelligent decision-making framework of“DRL evasion decision”+“impact prediction guidance decision”was established:it takes the impact point deviation correction ability as the constraint and the maximum miss distance as the objective,and effectively solves the problem of poor decisionmaking effect caused by the large IEI decision space.Second,to solve the sparse reward problem faced by evasion decision-making,a hierarchical decision-making method consisting of maneuver timing decision and maneuver duration decision was proposed,and the corresponding Markov Decision Process(MDP)was designed.A detailed simulation experiment was designed to analyze the advantages and computational complexity of the proposed method.Simulation results show that the proposed model has good performance and low computational resource requirement.The minimum miss distance is 21.3 m under the condition of guaranteeing the impact point accuracy,and the single decision-making time is 4.086 ms on an STM32F407 single-chip microcomputer,which has engineering application value.
基金principally supported by Deutsche Forschungsgemeinschaft grant to A.M.a Hector Fellow Academy Ph.D.fellowship and Jim Smith Endowment Fund Grant of the Ohio Cichlid Association to X.T.Deutsche Forschungsgemeinschaft grant to J.T.
文摘Cichlid fishes are a textbook example for adaptive radiations,since they diversified into several hundred highly specialized species in each of three great East African lakes.Even scale-eating,an extremely specialized feeding mode,evolved independently multiple times in these radiations and in Lake Tanganyika alone,six endemic scale-eating species occupy this extremely specialized ecological niche.Perissodus microlepis went a step further,by evolving bilaterally asymmetrical heads with an intra-specific polymorphism where left-and right-headed morphs predominantly scrape scales from the opposite sides of their prey.While the bilateral asymmetry of scale-eating cichlids has been known,exactly which craniofacial features explain the laterality of the heads remained unclear.Here we aimed,by utilizing micro-computed tomography(μCT),to resolve this issue of how bilateral symmetry in the skeletal structure is broken in scale-eating Perissodus.Our 3D geometric morphometrics analysis clearly separated and identified the two groups of either left-or right-headed fish.In addition,we observed consistent asymmetric volume changes in the premaxilla,maxilla,and mandible of the craniofacial structures,where left-headed fish have larger jaw elements on the right side,and vice versa.The bimodality implies that the effect sizes of environmental factors might be minor while genetics might be responsible to a larger extent for the asymmetry observed in their head morphology.High-speed video analyses of attacks by asymmetrical morphotypes revealed that they utilize their asymmetrical mouth protrusion,as well as lateralized behavior,to re-orientate the gape towards the preferred side of their prey fish to more efficiently scrape scales.
文摘BACKGROUND Safety and efficacy of intravascular ultrasound(IVUS)guidance in percutaneous coronary intervention(PCI)has been consistently shown in recent trials.However,prospective data on the clinical effects of IVUS usage in primary PCI are still warranted.The ULTRA-STEMI trial is a prospective investigator-initiated observational single-center cohort trial aiming to enroll 80 patients with STEMI.AIM To investigate the outcomes of patients with STEMI undergoing IVUS-guided PCI and correlate derived IVUS measurements with clinical,procedural,imaging and follow-up outcomes of interest.METHODS Study participants will undergo primary PCI as per standardized procedures.IVUS pullbacks will be performed pre-intervention,post-lesion preparation,postintervention and post-optimization using a 20 MHz digital IVUS(Eagle Eye Platinum,Philips).Manual thrombus aspiration will be performed in cases of high thrombus burden.The aspirated thrombi will be scanned with micro-computed tomography to extract volumetric measurements of the aspirated thrombotic burden.Moreover,angiographic,peri-procedural and 3-year follow-up data will be gathered.Co-primary endpoints will be cardiovascular mortality and target vessel failure,defined as the composite of:Cardiovascular mortality,target vessel myocardial infarction and/or clinically driven target vessel revascularization.RESULTS The results of the study are expected by the third quarter of 2029.CONCLUSION The ULTRA-STEMI trial will add to the existing literature the clinical,angiographic,micro-computed tomography and follow-up outcomes of IVUS-guided PCI in 80 patients presenting with STEMI.
基金the Chinese Academy of Sciences for their financial support and research facilitiesfunded by the National Key Research and Development Program of China(2022YFD1500100)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA28070100)the China Agriculture Research System of MOF and MARA(CARS04)。
文摘The accumulation of soil organic carbon(SOC)and total nitrogen(TN)is easily accomplished by returning crop straw,which strongly affects the formation and pore structure of aggregates,especially in black soil.We returned maize straw at different rates(6,000,9,000,12,000 and 15,000 kg ha^(-1))for nine years to investigate its influence on the SOC and TN contents in the SOC fractions of aggregates by combining size and density fractionation.Their subsequent influences on pore morphology and size distribution characteristics were examined using X-ray microcomputed tomography scanning(μCT).The results showed that returning straw significantly increased the contents of C and N in the SOC fractions of aggregates,especially at the return rates of 12,000 and 15,000 kg ha^(-1),which in turn promoted aggregate formation and stability,and ultimately amended pore structure.The pore size>100μm,porosity(>2μm),and morphological characteristics(anisotropy,circularity,connectivity and fractal dimension)significantly increased,but the total number of pores significantly decreased(P<0.05).Our results indicated that the amendment of the pore morphology and size distribution of soil aggregates was primarily controlled by the higher contents of C and N in the density fractions of aggregates,rather than in the aggregate sizes.Furthermore,this pore network reconfiguration favored the storage of C and N simultaneously.The findings of this study offer valuable new insights into the relationships between C and N storage and the pore characteristics in soil aggregates under straw return.
基金Project(41877240)supported by the National Natural Science Foundation of China。
文摘As a typical sedimentary soft rock,mudstone has the characteristics of being easily softened and disintegrated under the effect of wetting and drying(WD).The first cycle of WD plays an important role in the entire WD cycles.X-ray micro-computed tomography(micro-CT)was used as a non-destructive tool to quantitatively analyze microstructural changes of the mudstone due to the first cycle of WD.The test results show that WD leads to an increase of pore volume and pore connectivity in the mudstone.The porosity and fractal dimension of each slice of mudstone not only increase in value,but also in fluctuation amplitude.The pattern of variation in the frequency distribution of the equivalent radii of connected,isolated pores and pore throats in mudstone under WD effect satisfies the Gaussian distribution.Under the effect of WD,pores and pore throats with relatively small sizes increase the most.The sphericity of the pores in mudstones is positively correlated with the pore radius.The WD effect transforms the originally angular and flat pores into round and regular pores.This paper can provide a reference for the study of the deterioration and catastrophic mechanisms of mudstone under wetting and drying cycles.
基金supported by grants from the Human Resources Development program(Grant No.20204010600250)the Training Program of CCUS for the Green Growth(Grant No.20214000000500)by the Korea Institute of Energy Technology Evaluation and Planning(KETEP)funded by the Ministry of Trade,Industry,and Energy of the Korean Government(MOTIE).
文摘Three-dimensional printing(3DP)offers valuable insight into the characterization of natural rocks and the verification of theoretical models due to its high reproducibility and accurate replication of complex defects such as cracks and pores.In this study,3DP gypsum samples with different printing directions were subjected to a series of uniaxial compression tests with in situ micro-computed tomography(micro-CT)scanning to quantitatively investigate their mechanical anisotropic properties and damage evolution characteristics.Based on the two-dimensional(2D)CT images obtained at different scanning steps,a novel void ratio variable was derived using the mean value and variance of CT intensity.Additionally,a constitutive model was formulated incorporating the proposed damage variable,utilizing the void ratio variable.The crack evolution and crack morphology of 3DP gypsum samples were obtained and analyzed using the 3D models reconstructed from the CT images.The results indicate that 3DP gypsum samples exhibit mechanical anisotropic characteristics similar to those found in naturally sedimentary rocks.The mechanical anisotropy is attributed to the bedding planes formed between adjacent layers and pillar-like structures along the printing direction formed by CaSO_(4)·2H_(2)O crystals of needle-like morphology.The mean gray intensity of the voids has a positive linear relationship with the threshold value,while the CT variance and void ratio have concave and convex relationships,respectively.The constitutive model can effectively match the stress–strain curves obtained from uniaxial compression experiments.This study provides comprehensive explanations of the failure modes and anisotropic mechanisms of 3DP gypsum samples,which is important for characterizing and understanding the failure mechanism and microstructural evolution of 3DP rocks when modeling natural rock behavior.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB1002010)the Major Program for the Fundamental Research of Shanghai Committee of Science and Technology(No.12JC1410400)the National Natural Science Foundation of China for Distinguished Young Scholars(No.41325016)
文摘Microstructure of shale formation is the key to understanding its petrophysical and chemical properties.Optical microscopy, scanning electron microscopy and micro-computed tomography(μ-CT) have been combined for characterization of microstructure of Longmaxi(LMX)shale from Shizhu area, Sichan Basin. The results indicate that laminated LMX shale consists of mineral matrix-rich layers and organic matter(OM)-rich layers at micrometer scale in two and three dimensions. Mineral matrix layers,mainly consisting of interparticle pores and intraplatelet pores, are approximately parallel to the bedding plane.Pyrite-rich layer, mainly containing intercrystalline pores,shows a strong preferred orientation parallel to the bedding plane. OM-rich layer, mainly containing OM pores, seems to be discontinuous. In addition, intercrystalline pores are enriched in some layers, while OM pores are distributed irregularly in matrix layers. This vertical heterogeneity of pore microscopic structures in LMX shale is of great importance to understand its petrophysical and chemical properties.
文摘This study aimed to utilize micro-computed tomography （micro-CT） analysis to compare new bone formation in rat calvarial defects using chitosan/fibroin-hydroxyapatite （CFB-HAP） or collagen （Bio-Gide） membranes. Fifty-four （54） rats were studied. A circular bony defect （8 mm diameter） was formed in the centre of the calvaria using a trephine bur. The CFB-HAP membrane was prepared by thermally induced phase separation. In the experimental group （n= 18）, the CFB-HAP membrane was used to cover the bony defect, and in the control group （n= 18）, a resorbable collagen membrane （Bio-Gide） was used. In the negative control group （n= 18）, no membrane was used. In each group, six animals were euthanized at 2, 4 and 8 weeks after surgery. The specimens were then analysed using micro-CT. There were significant differences in bone volume （BV） and bone mineral density （BMD） （P〈O.05） between the negative control group and the membrane groups. However, there were no significant differences between the CFB-HAP group and the collagen group. We concluded that the CFB-HAP membrane has significant potential as a guided bone regeneration （GBR） membrane.
基金Sponsored by the National Natural Science Foundation of China(Grant No. 59908001)Multidiscipline Scientific Research Foundation of Harbin Institute of Technology(Grant No. HIT. MD200030)
文摘Length and concise structure of fuzzy logic reasoning program and its real-time reasoning characteris-tic have their effect on the performance of a digital single-chip fuzzy controller. The control effect of a digitalfuzzy controller based on looking up fuzzy control responding table is only relative to the table and not relative tothe fuzzy control rules in the practical control process. Aiming at above problem and having combined fuzzy log-ic reasoning with digital operational characteristics of a single-chip microcomputer, functioning-fuzzy-subset in-ference (FFSI) in binary, in which triangle membership functions of error and error-in-change are all represen-ted in binary and singleton membership functions of control variable is binary too, has been introduced. The cir-cuit principle plans of a single-chip fuzzy controller have been introduced for development of its hardware, andthe primary program structure, fuzzy logic reasoning subroutine, serial communication subroutine with PC andreliability design of the fuzzy controller are all discussed in detail. The control of indoor temperature by a fuzzycontroller has been conducted using a testing-room thermodynamic system. Research results show that the FFSIin binary can exercise a concise fuzzy control in a single-chip fuzzy controller, and the fuzzy controller is there-fore reliable and possesses a high performance-price ratio.
基金supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (grant numbers: NRF-2015R1C1A1A01052498 and NRF2014R1A1A1006010)
文摘We successfully obtained 3D skeletal images of Hyla suweonensis, employing a nondestructive method by applying appropriate anesthesia and limiting the radiation dose. H. suweonensis is a tree frog endemic to Korea and is on the list of endangered species. Previous studies have employed caliper-based measurements and two-dimensional （2D） X-ray imaging for anatomical analyses of the skeletal system or bone types of H. suweonensis. In this work we reconstructed three-dimensional （3D） skeletal images of H. suweonensis, utilizing a nondestructive micro-computed tomography （micro-CT） with a short scan and low radiation dose （i.e. 4 min and 0.16 Gy）. Importantly, our approach can be applied to the imaging of 3D skeletal systems of other endangered frog species, allowing both versatile and high contrast images of anatomical structures without causing any significant damages to the living animal.
基金supported by the program of Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Provincethe Hunan Province and Xiangtan City Natural Science Joint Foundation(No.09JJ8005)+1 种基金the Industrial Cultivation Program of Scientific and Technological Achievements in Higher Educational Institutions of Hunan Province(No.10CY008)the Technologies R & D of Hunan Province (No.2010CK3031)
文摘This paper is aimed at the actual conditions of disaster caused by gas in small and medium-sized coal mines. A new gas concentration monitoring system for coal mines is developed on the basis of gas-sensing detection and single-chip control. The monitoring system uses the tin oxide as the main material of N-type semiconductor gas sensors, be- cause it has good sensitive characteristics for the flammable and explosive gas （ such as methane, carbon monoxide）. The QM-N5-semiconductor gas sensor is adopted to detect the output values of the resistance under the different gas con- centrations. The system, designedly, takes the AT89C51 digital chip as the core of the circuit processing hardware structure to analyze and judge the input values of the resistance, and then achieve the control and alarm for going beyond the limit of gas concentration. The gas concentration monitoring system has man）, advantages including simple in struc- ture, fast response time, stable performance and low cost. Thus, it can be widely used to monitor gas concentration and provide early wamings in small and medium-sized coal mines.
基金Supported by National Natural Science Fund,No.81270558
文摘AIM: To explore the potential of contrast-enhanced computed tomography(CECT) using Exi Tron nano6000 for assessment of liver lesions in mouse models.METHODS: Three mouse models of liver lesions were used: bile duct ligation(BDL),lipopolysaccharide(LPS)/D-galactosamine(D-Gal N),and alcohol.After injection with the contrast agent Exi Tron nano6000,the mice were scanned with micro-CT.Liver lesions were evaluated using CECT images,hematoxylin and eosin staining,and serum aminotransferase levels.Macrophage distribution in the injury models was shown by immunohistochemical staining of CD68.The in vitro studies measured the densities of RAW264.7 under different conditions by CECT.RESULTS: In the in vitro studies,CECT provided specific and strong contrast enhancement of liver in mice.CECT could present heterogeneous images anddensities of injured livers induced by BDL,LPS/D-Gal N,and alcohol.The liver histology and immunochemistry of CD68 demonstrated that both dilated biliary tracts and necrosis in the injured livers could lead to the heterogeneous distribution of macrophages.The in vitro study showed that the RAW264.7 cell masses had higher densities after LPS activation.CONCLUSION: Micro-CT with the contrast agent Exi Tron nano6000 is feasible for detecting various liver lesions by emphasizing the heterogeneous textures and densities of CECT images.
文摘In order to study the microstructure characteristics of normal lunate bones, eight fresh cadaver normal lunates were scanned with micro-computed tomography. High-resolution images of the micro-structure of normal lunates were obtained and we analyzed the nutrient foramina. Then nine regions of interest(ROI) were chosen in the central sagittal plane so that we could obtain the parameters of trabecular bones of ROIs. The distal lamellar-like compact structure had statistically significant differences when it was compared with the ROIs in the volar and dorsal ends of the distal cortex. The difference of diameter between the volar and dorsal foramina was significant(P<0.05). However, there was no significant difference regarding the number. The trabecular bones of the volar and dorsal distal ends had lower intensity than those of the distal central subchondral bone plate. The diameters of the nutrient foramina on the volar cortex were larger than those on the dorsal. This research provided more detailed information about microstructure of normal lunate and the nutrient foramina on cortex, and a reference for further study about diseased lunate.
文摘A single-chip UHF RFID reader transceiver IC has been implemented in 0.18 μm SiGe BiCMOS technology. The chip includes all transceiver blocks as RX/TX RF front-end, RX/TX analog baseband, frequency synthesizer and I2C with fully-compliant China 800/900 MHz RFID draft, ISO/IEC 18000-6C protocol and ETSI 302 208-1 local regulation. The normal mode receiver in the presence of -3 dBm self-jammer achieves -75 dBm 1% PER sensitivity. The linear class-A PA integrated in transmitter has 25 dBm OP1 dB output power for CW. The fully-integrated fractional-N fre-quency synthesizer is designed based on MASH 1-1-1 sigma-delta modulator and 1.8 GHz fundamental frequency LC-VCO for lower in-band and out-of-band phase noise. The measured phase noise is up to -106 dBc/Hz@200 kHz and -131 dBc/Hz@1 MHz offset from center frequency and the integrated RMS jitter from 10 kHz to 10 MHz is less than 1.6 pS. The chip dissipates 330 mA from 3.3 V power supply when transmitting 22.4 dBm CW signal and the PAE of linear PA is up to 26%. The chip die area is 16.8 mm2.
文摘The aim of this study was to determine whether contrast-enhanced micro-computed tomography can be used for non-invasive imaging of the early-stage changes in the vasculature of tumours that have been treated with photodynamic therapy (PDT). The subjects used were C3H mice with an RIF-1 tumour implanted subcutaneously and allowed to grow for 3 weeks prior to treatment. The experimental groups were PDT-treated (150 J/cm2 and 50 J/cm2) and control (150 J/cm2 light-only and untreated). The laser light exposure was performed at 15 - 30 minutes after the administration of the photosensitizer (BPD-MA). The contrast-enhanced micro-computed tomography imaging procedure consisted of eight-second scans taking place before treatment and up to 24 hours after treatment. The 150 J/cm2 PDT group showed a significant increase in the ratio of blood volume to tumour volume at 2, 8 and 24 hours after treatment when compared to pre-treatment measurements (p 2 PDT group at 24 hours after treatment. This preliminary study indicates that micro-CT can detect compromised vasculature in tumours treated with high-fluence photodynamic therapy as early as 2 hours post treatment.
基金the Portuguese research foundation FCT(Fundacao para a Ciencia e Tecnologia)for providing financial support(SFRH/BD/48100/2008)MFC Pereira and A Mauricio acknowledge FEDER Funds through Programa Operacional Factores de Com-petitividade-COMPETE,and FCT Project PEst-OE/CTE/UI0098/2011
文摘The aim of this study was to identify three-dimensional microstructural changes of trabecular bone with age and gender, using micro-computed tomography. Human trabecular bone from two disease groups, osteoporosis and osteoarthritis was analyzed. A prior analysis of the effects of some procedure variables on the micro-CT results was performed. Preliminary micro-CT scans were performed with three voxel resolutions and two acquisition conditions. On the reconstruction step, the image segmentation was performed with three different threshold values. Samples were collected from patients, with coxarthrosis (osteoarthritis) or fragility fracture (osteoporosis). The specimens of the coxarthrosis group include twenty females and fifteen males, while the fragility fracture group was composed by twenty three females and seven males. The mean age of the population was 69 ± 11 (females) and 67 ± 10 years (males), in the coxarthrosis group, while in the fragility fracture group was 81 ± 6 (females) and 78 ± 6 (males) years. The 30 μm voxel size provided lower percentage difference for the microarchitecture parameters. Acquisition conditions with 160 μA and 60 kV permit the evaluation of all the volume’s sample, with low average values of the coefficients of variation of the microstructural parameters. No statistically significant differences were found between the two diseases groups, neither between genders. However, with aging, there is a decrease of bone volume fraction, trabecular number and fractal dimension, and an increase of structural model index and trabecular separation, for both disease groups and genders. The parameters bone specific surface, trabecular thickness and degree of anisotropy have different behaviors with age, depending on the type of disease. While in coxarthrosis patients, trabecular thickness increases with age, in the fragility fracture group, there is a decrease of trabecular thickness with increasing age. Our findings indicate that disease, age and gender do not provide significant differences in trabecular microstructure. With aging, some parameters exhibit different trends which are possibly related to different mechanisms for different diseases.
基金the National Natural Science Foundation of China(Nos.52122402,12172334,52034010,52174051)Shandong Provincial Natural Science Foundation(Nos.ZR2021ME029,ZR2022JQ23)Fundamental Research Funds for the Central Universities(No.22CX01001A-4)。
文摘The phase behavior of gas condensate in reservoir formations differs from that in pressure-volume-temperature(PVT)cells because it is influenced by porous media in the reservoir formations.Sandstone was used as a sample to investigate the influence of porous media on the phase behavior of the gas condensate.The pore structure was first analyzed using computed tomography(CT)scanning,digital core technology,and a pore network model.The sandstone core sample was then saturated with gas condensate for the pressure depletion experiment.After each pressure-depletion state was stable,realtime CT scanning was performed on the sample.The scanning results of the sample were reconstructed into three-dimensional grayscale images,and the gas condensate and condensate liquid were segmented based on gray value discrepancy to dynamically characterize the phase behavior of the gas condensate in porous media.Pore network models of the condensate liquid ganglia under different pressures were built to calculate the characteristic parameters,including the average radius,coordination number,and tortuosity,and to analyze the changing mechanism caused by the phase behavior change of the gas condensate.Four types of condensate liquid(clustered,branched,membranous,and droplet ganglia)were then classified by shape factor and Euler number to investigate their morphological changes dynamically and elaborately.The results show that the dew point pressure of the gas condensate in porous media is 12.7 MPa,which is 0.7 MPa higher than 12.0 MPa in PVT cells.The average radius,volume,and coordination number of the condensate liquid ganglia increased when the system pressure was between the dew point pressure(12.7 MPa)and the pressure for the maximum liquid dropout,Pmax(10.0 MPa),and decreased when it was below Pmax.The volume proportion of clustered ganglia was the highest,followed by branched,membranous,and droplet ganglia.This study provides crucial experimental evidence for the phase behavior changing process of gas condensate in porous media during the depletion production of gas condensate reservoirs.
基金funded by the National Natural Science Foundation of China(NSFC,U21A20270)the Key R&D Program of Shandong Province,China(2023TZXD074)+2 种基金the Bingtuan Science and Technology Program,China(2023AB002)the National Peanut Industry Technology System of China(CARS-13-08B)the National Key R&D Program of China(2021YFD2100402)。
文摘This study develops low-fat microwaved peanut snacks(LMPS)using partially defatted peanuts(PDP)with different defatting ratios,catering to people’s pursuit of healthy,low-fat cuisine.The effects of defatting treatment on the structural characteristics,texture,color,and nutrient composition of LMPS were comprehensively explored.The structural characteristics of LMPS were characterized using X-ray micro-computed tomography(Micro-CT)and scanning electron microscope(SEM).The results demonstrated that the porosity,pore number,pore volume,brightness,brittleness,protein content,and total sugar content of LMPS all significantly increased(P<0.05)with the increase in the defatting ratio.At the micro level,porous structure,cell wall rupture,and loss of intracellular material could be observed in LMPS after defatting treatments.LMPS made from PDP with a defatting ratio of 64.44%had the highest internal pore structural parameters(porosity 59%,pore number 85.3×10^(5),pore volume 68.23 mm3),the brightest color(L^(*) 78.39±0.39),the best brittleness(3.64±0.21)mm^(–1)),and the best nutrition(high protein content,(34.02±0.38)%;high total sugar content,(17.45±0.59)%;low-fat content,(27.58±0.85)%).The study provides a theoretical basis for the quality improvement of LMPS.
