X-ray computed tomography

X 线计算机断层扫描
  • 文章类型: Journal Article
    目的:建立基于常规CT征象和肿瘤微环境免疫类型(TIMT)的模型,以预测非小细胞肺癌(NSCLC)术后辅助化疗的持续临床获益(DCB)。
    方法:205例非小细胞肺癌患者术前接受CT检查,分为两组:DCB(无进展生存期(PFS)≥18个月)和非DCB(NDCB,PFS<18个月)。对PD-L1和CD8+肿瘤浸润淋巴细胞(TIL)的密度百分位数进行定量以估计TIMT。收集临床特征和常规CT征象。采用多变量逻辑回归来选择最有区别的参数,构建一个预测模型,并将模型可视化为列线图。接收器工作特性(ROC)曲线,校正曲线,和决策曲线分析(DCA)用于评估预测性能和临床效用。
    结果:118例DCB和87例NDCBNSCLC患者接受术后辅助化疗。DCB组和NDCB组之间的TIMT差异有统计学意义(P<0.05)。临床特征(神经元特异性烯醇化酶,鳞状细胞癌抗原,Ki-76和cM期)和常规CT征象(棘突,泡沫般的透明度,胸膜回缩,最大直径,和静脉相的CT值)在四个TIMT组之间存在差异(P<0.05)。此外,DCB组和NDCB组的临床特征(淋巴细胞计数[LYMPH]和cM分期)和常规CT征象(气泡样透明和胸腔积液)存在差异(P<0.05)。多变量分析表明,TIMT,cM阶段,LYMPH,和胸腔积液与DCB独立相关,并用于构建列线图。联合模型的曲线下面积(AUC)为0.70(95CI:0.64-0.76),敏感性和特异性分别为0.73和0.60。
    结论:常规CT征象和TIMT为预测NSCLC术后辅助化疗患者的临床结局提供了一种有希望的方法。
    OBJECTIVE: To develop a model based on conventional CT signs and the tumor microenvironment immune types (TIMT) to predict the durable clinical benefits (DCB) of postoperative adjuvant chemotherapy in non-small cell lung cancer (NSCLC).
    METHODS: A total of 205 patients with NSCLC underwent preoperative CT and were divided into two groups: DCB (progression-free survival (PFS) ≥ 18 months) and non-DCB (NDCB, PFS <18 months). The density percentiles of PD-L1 and CD8 + tumor-infiltrating lymphocytes (TIL) were quantified to estimate the TIMT. Clinical characteristics and conventional CT signs were collected. Multivariate logistic regression was employed to select the most discriminating parameters, construct a predictive model, and visualize the model as a nomogram. Receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA) were used to evaluate prediction performance and clinical utility.
    RESULTS: Precisely 118 patients with DCB and 87 with NDCB in NSCLC received postoperative adjuvant chemotherapy. TIMT was statistically different between the DCB and NDCB groups (P < 0.05). Clinical characteristics (neuron-specific enolase, squamous cell carcinoma antigen, Ki-76, and cM stage) and conventional CT signs (spiculation, bubble-like lucency, pleural retraction, maximum diameter, and CT value of the venous phase) varied between the four TIMT groups (P < 0.05). Furthermore, clinical characteristics (lymphocyte count [LYMPH] and cM stage) and conventional CT signs (bubble-like lucency and Pleural effusion) differed between the DCB and NDCB groups (P < 0.05). Multivariate analysis revealed that TIMT, cM stage, LYMPH, and pleural effusion were independently associated with DCB and were used to construct a nomogram. The area under the curve (AUC) of the combined model was 0.70 (95%CI: 0.64-0.76), with sensitivity and specificity of 0.73 and 0.60, respectively.
    CONCLUSIONS: Conventional CT signs and the TIMT offer a promising approach to predicting clinical outcomes for patients treated with postoperative adjuvant chemotherapy in NSCLC.
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  • 文章类型: Journal Article
    目的:本研究的目的是研究单侧和双侧冠状颅前突(FOA)手术后颅骨生长的纵向变化。
    方法:这项回顾性研究分析了术前(T0)头围(HC)和CT数据,术后即刻(T1),40例患者(23例女性,17名男性),在1987年至2018年之间使用开放方法或牵引成骨(DO)进行了FOA。平均随访期为90.62个月。HC的z分数,基于CT的颅内容积,前后径(APD),双顶直径(BPD),和颅骨高度(CH)使用性别和年龄特异性标准进行计算。进行Logistic回归分析。
    结果:虽然HC的z分数,颅内容积,BPD保持在正常范围内,APD的z评分在-2和-1之间波动,CH的z评分>2,表明从T0到T2与常模相比显著升高.手术年龄显著影响HC的z评分,BPD,和CH在T2(所有p<0.05)。手术时机的延迟与从T1到T2的BPD和CHz评分增加相关(分别为p=0.007和0.019)。FOA的DO导致T2时HCz评分升高,从T0到T1APD增加,然后从T1到T2APD复发。
    结论:这些研究结果表明,延迟手术时机可能支持更好的颅骨生长,如长期随访中HC增加所示。然而,延迟的时机也与异常升高的CH恶化有关。尽管立即APD扩张和长期HC随着DO增加,潜在的复发值得谨慎。虽然建议故意过度校正APD,仔细考虑手术时机和计划至关重要。
    OBJECTIVE: The objective of this study was to investigate the longitudinal changes in cranial growth following fronto-orbital advancement (FOA) surgery in patients with unilateral and bilateral coronal craniosynostosis.
    METHODS: This retrospective review analyzed head circumference (HC) and CT data during preoperative (T0), immediate postoperative (T1), and final follow-up (T2) visits in 40 patients (23 female, 17 male) who underwent FOA using either the open approach or distraction osteogenesis (DO) between 1987 and 2018. The mean follow-up period was 90.62 months. The z-scores of HC, CT-based intracranial volume, anteroposterior diameter (APD), biparietal diameter (BPD), and cranial height (CH) were calculated using sex- and age-specific standards. Logistic regression analysis was performed.
    RESULTS: While the z-scores of HC, intracranial volume, and BPD remained within the normal range, the z-scores of APD fluctuated between -2 and -1, and the z-scores of CH were > 2, indicating a substantial elevation compared with norms from T0 to T2. Age at surgery significantly influenced the z-scores of HC, BPD, and CH at T2 (all p < 0.05). Delayed surgical timing was correlated with increased BPD and CH z-scores from T1 to T2 (p = 0.007 and 0.019, respectively). The DO for FOA resulted in elevated HC z-scores at T2 and increased APD from T0 to T1, followed by a significant APD relapse from T1 to T2.
    CONCLUSIONS: These findings suggest that delayed surgical timing may support better cranial growth, as indicated by increased HC at long-term follow-up. However, delayed timing is also associated with worsening abnormally elevated CH. Despite the immediate APD expansion and long-term HC increase with DO, potential relapse warrants caution. While intentional overcorrection of APD is recommended, careful consideration of surgical timing and planning is essential.
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  • 文章类型: Journal Article
    目的:对胸部疾病中与双能量和多能量CT相关的前景和障碍进行文献计量学分析,强调其目前的地位,优势,和需要注意的领域。
    方法:向WebofScienceCoreCollection查询了有关双能量和多能量CT以及胸部应用的相关出版物,而没有限制出版日期或语言。Bibliometrix软件包,VOSviewer,和CiteSpace用于数据分析。使用的文献计量技术是共同作者分析,趋势主题,专题地图分析,主题演变分析,源的生产随着时间的推移,相应的作者国家,和作者\'关键字的树图。
    结果:这项研究共检查了1992年的出版物和来自313个不同来源的7200名作者。第一份可用文件于1982年11月发布,被引用次数最多的文章被引用了1200次。西门子股份公司在德国成为最杰出的作者隶属关系,共发表221篇文章。最具代表性的科学期刊是“欧洲放射学”(181篇文章,h-index=46),其次是“欧洲放射学杂志”(148篇文章,h-index=34)。大部分论文来自德国,美国,或者中国。关键词和主题分析均显示了双能量和多能量CT的历史及其在胸部应用热点的演变。
    结论:我们的研究说明了双能量和多能量CT的最新进展及其在胸部的应用日益突出,尤其是肺实质疾病和冠状动脉疾病。光子计数CT和人工智能将是未来不断发展的新兴热点技术。
    这项研究旨在为胸部疾病的能量成像提供有价值的见解,验证了多能量CT与光子计数CT的临床应用,有效提高了临床利用率。
    结论:文献计量学分析是理解双能量和多能量CT当前和未来状态的基础。研究趋势和主要主题包括冠状动脉疾病,肺栓塞,和辐射剂量。所有分析都表明人们对将基于能量的成像技术用于胸部应用越来越感兴趣。
    OBJECTIVE: To conduct a bibliometric analysis of the prospects and obstacles associated with dual- and multi-energy CT in thoracic disease, emphasizing its current standing, advantages, and areas requiring attention.
    METHODS: The Web of Science Core Collection was queried for relevant publications in dual- and multi-energy CT and thoracic applications without a limit on publication date or language. The Bibliometrix packages, VOSviewer, and CiteSpace were used for data analysis. Bibliometric techniques utilized were co-authorship analyses, trend topics, thematic map analyses, thematic evolution analyses, source\'s production over time, corresponding author\'s countries, and a treemap of authors\' keywords.
    RESULTS: A total of 1992 publications and 7200 authors from 313 different sources were examined in this study. The first available document was published in November 1982, and the most cited article was cited 1200 times. Siemens AG in Germany emerged as the most prominent author affiliation, with a total of 221 published articles. The most represented scientific journals were the \"European Radiology\" (181 articles, h-index = 46), followed by the \"European Journal of Radiology\" (148 articles, h-index = 34). Most of the papers were from Germany, the USA, or China. Both the keyword and topic analyses showed the history of dual- and multi-energy CT and the evolution of its application hotspots in the chest.
    CONCLUSIONS: Our study illustrates the latest advances in dual- and multi-energy CT and its increasingly prominent applications in the chest, especially in lung parenchymal diseases and coronary artery diseases. Photon-counting CT and artificial intelligence will be the emerging hot technologies that continue to develop in the future.
    UNASSIGNED: This study aims to provide valuable insights into energy-based imaging in chest disease, validating the clinical application of multi-energy CT together with photon-counting CT and effectively increasing utilization in clinical practice.
    CONCLUSIONS: Bibliometric analysis is fundamental to understanding the current and future state of dual- and multi-energy CT. Research trends and leading topics included coronary artery disease, pulmonary embolism, and radiation dose. All analyses indicate a growing interest in the use of energy-based imaging techniques for thoracic applications.
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  • 文章类型: Journal Article
    纤维发育不良/McCune-Albright综合征(FD/MAS)经常涉及颅面骨骼。颅面纤维发育不良病变在多模态评估中表现出多样化的影像学特征,利用射线照片,计算机断层扫描(CT),磁共振成像(MRI),和18F-氟化钠正电子发射断层扫描(18F-NaFPET)。颅面纤维发育不良病变的多模态成像分类可以提供对(1)易于进展的病变类型的临床见解,(2)适合干预(即,药理学或外科),或(3)与疼痛等症状相关。在这个前景中,15例FD/MAS患者的初步单中心研究,使用18F-NaFPET组合评估颅面病变的异质性(N=35),MRI,和CT。采用k-means聚类算法根据影像特征对病灶进行分类。聚类分析根据区域18F-NaF标准化摄取值(SUV)的大小揭示了三种类型的病变,T1加权和流体敏感序列上的信号强度,和CT上的外观(朗肯,硬化,和/或磨砂玻璃)。这项初步研究为未来的纵向自然史或治疗研究奠定了基础,可以进一步评估基线颅面纤维发育不良影像学特征和临床症状的预后价值。
    Fibrous dysplasia/McCune-Albright Syndrome (FD/MAS) frequently involves the craniofacial skeleton. Craniofacial fibrous dysplasia lesions exhibit diverse imaging characteristics on multimodality evaluation, utilizing radiographs, computed tomography (CT), magnetic resonance imaging (MRI), and 18F-sodium fluoride positron emission tomography (18F-NaF PET). A multimodal imaging classification of craniofacial fibrous dysplasia lesions may offer clinical insights into the types of lesions that are (1) prone to progression, (2) amenable to intervention (i.e., pharmacological or surgical), or (3) associated with symptoms such as pain. In this prospective, preliminary single site study of 15 patients with FD/MAS, the heterogeneity of craniofacial lesions (N = 35) was assessed using a combination of 18F-NaF PET, MRI, and CT. A k-means clustering algorithm was used to categorize lesions based on imaging characteristics. Clustering analysis revealed three types of lesion based on the magnitude of the regional 18F-NaF standardized uptake values (SUV), signal intensities on T1-weighted and fluid-sensitive sequences, and appearance on CT (lucent, sclerotic, and/or ground glass). This preliminary study provides a foundation for future longitudinal natural history or treatment studies, where the prognostic value of baseline craniofacial fibrous dysplasia imaging characteristics and clinical symptomatology can be further evaluated.
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  • 文章类型: Journal Article
    本文研究了单元尺寸对自密实混凝土(SCC)中钢-混凝土界面微观结构的影响。对两种类型的测试元件进行了实验:深梁1440×640×160mm和壁元件2240×1600×160mm。SCC混合物始终从顶部泵送,使用位于模板边缘附近的单个铸造点。将直径为16mm的水平钢带肋钢筋嵌入这些元件中。X射线计算机断层扫描(CT)用于提供对钢筋与混凝土界面微观结构的三维见解。对岩心样品的X射线CT图像的分析表明,该界面的微观结构受样品与混合浇铸点的距离及其在元件内的垂直位置的影响。出血的综合影响,空气孔截留,在顶部钢筋下观察到SCI内的塑性沉降。它们的范围与所分析元素的类型无关,这表明SCI的劣化与元件顶面的距离有关。这些结果阐明了在钢筋附近的混凝土新鲜状态期间发生的现象及其对粘结性能的影响。迄今为止,一些标准根据钢筋下混凝土的深度来区分粘结条件。在研究中,这种方法可能过于严格。研究结果为钢筋混凝土的执行和设计提供了有价值的指导。
    This paper investigates the impact of element size on the microstructure of the steel-concrete interface in self-compacting concrete (SCC). Experiments were conducted on two types of test elements: a deep beam measuring 1440 × 640 × 160 mm and a wall element measuring 2240 × 1600 × 160 mm. The SCC mix was consistently pumped from the top, using a single casting point located near the formwork\'s edge. Horizontal steel ribbed rebars with a diameter of 16 mm were embedded in these elements. X-ray computed tomography (CT) was employed to provide three-dimensional insights into the microstructure of the rebar-to-concrete interface. An analysis of X-ray CT images from core samples revealed that the microstructure of this interface is influenced by the distance of the specimen from the mix casting point and its vertical position within the element. The combined effects of bleeding, air-pore entrapment, and plastic settlement within the SCI were observed under the top rebars. Their extent was independent of the type of element analyzed, suggesting that the deterioration of the SCI is related to the distance from the top surface of the element. These results elucidate phenomena occurring during the fresh state of concrete near reinforcing bars and their implications for bond properties. To date, some of the standards differentiate between bond conditions according to the depth of concrete beneath the rebar. In the view of the studies, this approach may be unduly rigorous. The findings offer valuable guidance for reinforced concrete execution and design.
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  • 文章类型: Journal Article
    目的:利用双能计算机断层扫描(DECT)结合临床表现,构建预测N0期非小细胞肺癌(NSCLC)淋巴血管侵犯(LVI)的列线图。
    方法:我们回顾性招募了来自两家医院的135例N0期NSCLC患者,这些患者在手术前接受了DECT,分为发展队列(n=107)和验证队列(n=28)。临床发现(基线特征,生化标志物,血清肿瘤标志物和免疫组织化学标志物),DECT衍生参数(碘浓度[IC],有效原子序数[Eff-Z]和归一化碘浓度[NIC],收集并测量碘增强[IE]和NIC比[NICr])和分形维数(FD)。使用重要发现构建列线图以预测N0期NSCLC中的LVI,并进行外部验证。
    结果:多变量分析显示淋巴细胞计数(LYMPH,比值比[OR]:3.71,P=0.014),动脉期IC(ICa,OR:1.25,P=0.021),静脉阶段的NIC(NICv,OR:587.12,P=0.009)和FD(OR:0.01,P=0.033)是N0期NSCLCLVI的独立影响因素,并被用来构造列线图。列线图在开发和验证队列中均表现出强大的预测能力,AUC为0.819(95%CI:72.6-90.4)和0.844(95%CI:68.2-95.8),分别。校准图显示了预测概率和实际LVI阳性率之间的极好一致性,在外部验证上。
    结论:临床和DECT影像学检查结果的结合可以使用LYMPH的重要发现来帮助预测N0期NSCLC的LVI,ICa,NICv和FD。
    OBJECTIVE: To construct a nomogram for predicting lymphovascular invasion (LVI) in N0 stage non-small cell lung cancer (NSCLC) using dual-energy computed tomography (DECT) findings combined with clinical findings.
    METHODS: We retrospectively recruited 135 patients with N0 stage NSCLC from two hospitals underwent DECT before surgery and were divided into development cohort (n = 107) and validation cohort (n = 28). The clinical findings (baseline characteristics, biochemical markers, serum tumor markers and Immunohistochemical markers), DECT-derived parameters (iodine concentration [IC], effective atomic number [Eff-Z] and normalized iodine concentration [NIC], iodine enhancement [IE] and NIC ratio [NICr]) and Fractal dimension (FD) were collected and measured. A nomogram was constructed using significant findings to predict LVI in N0 stage NSCLC and was externally validated.
    RESULTS: Multivariable analysis revealed that lymphocyte count (LYMPH, odds ratio [OR]: 3.71, P=0.014), IC in arterial phase (ICa, OR: 1.25, P=0.021), NIC in venous phase (NICv, OR: 587.12, P=0.009) and FD (OR: 0.01, P=0.033) were independent significant factors for predicting LVI in N0 stage NSCLC, and were used to construct a nomogram. The nomogram exhibited robust predictive capabilities in both the development and validation cohort, with AUCs of 0.819 (95 % CI: 72.6-90.4) and 0.844 (95 % CI: 68.2-95.8), respectively. The calibration plots showed excellent agreement between the predicted probabilities and the actual rates of positive LVI, on external validation.
    CONCLUSIONS: Combination of clinical and DECT imaging findings could aid in predicting LVI in N0 stage NSCLC using significant findings of LYMPH, ICa, NICv and FD.
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  • 文章类型: Journal Article
    水果和蔬菜(F&V)是非常复杂的产品,具有高度多样化的化学和结构特征。先进的成像技术要么将成像与光谱信息相结合,要么可以提供出色的组织穿透性,并有可能瞄准,可视化甚至定性F&V中的化学和物理(结构)异质性在这次审查中,可见和/或近红外高光谱成像,傅里叶变换红外显微光谱成像,拉曼成像,X射线和磁共振成像,以揭示F&V在宏观(整个产品)的空间背景下的化学和结构信息,中观-(组织),和微(单个细胞)尺度进行了全面总结。此外,他们的基本概念和操作程序,特别是样品制备和仪器参数调整,已解决。最后,提出了这些技术未来的挑战和前景。这些成像技术是评估F&V的生化和结构异质性的强大工具。降低成本,传感器融合和数据共享平台是未来的发展趋势。更加强调学术和研究层面的知识和推广方面,特别是如何选择技术,选择操作参数并准备样品,重要的是克服障碍,更广泛地采用这些技术,以提高F&V质量的评估。
    高光谱成像揭示了水果和蔬菜的化学异质性。成像技术提供了多种尺度的水果和蔬菜的空间见解。未来的趋势是降低成本,传感器融合和数据共享。仪器调整和样品制备应得到更多关注。
    Fruit and vegetables (F&V) are vastly complicated products with highly diverse chemical and structural characteristics. Advanced imaging techniques either combine imaging with spectral information or can provide excellent tissue penetration, and enable the possibility to target, visualize and even qualify the chemical and physical (structural) heterogeneity within F&V. In this review, visible and/or near infrared hyperspectral imaging, Fourier transform infrared microspectroscopic imaging, Raman imaging, X-ray and magnetic resonance imaging to reveal chemical and structural information in a spatial context of F&V at the macro- (entire products), meso- (tissues), and micro- (individual cells) scales are comprehensively summarized. In addition, their basic concepts and operational procedures, particularly sample preparation and instrumental parameter adjustments, are addressed. Finally, future challenges and perspectives of these techniques are put forward. These imaging techniques are powerful tools to assess the biochemical and structural heterogeneity of F&V. Cost reduction, sensor fusion and data sharing platforms are future trends. More emphasis on aspects of knowledge and extension at the level of academia and research, especially on how to select techniques, choose operational parameters and prepare samples, are important to overcome barriers for the wider adoption of these techniques to improve the evaluation of F&V quality.
    Hyperspectral imaging reveals chemical heterogeneity of fruit and vegetables.Imaging techniques provide spatial insights in fruit and vegetables at multiple scales.Future trends are cost reduction, sensor fusion and data sharing.Instrumental adjustment and sample preparation should receive more attention.
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  • 文章类型: Journal Article
    这项研究的目的是确定治疗前肌肉减少症的预后价值。定义的放射学(颈部(C3)或腰部(L3)区域),在接受治愈性治疗的成年头颈部癌症(HNC)患者中。截至2024年3月,对PubMed和Scopus数据库进行了系统搜索。纳入标准为成人局部晚期HNC患者,在C3和/或L3水平放射学定义的肌肉减少症,和接受具有治愈意图的主要治疗的患者。使用ROBINS-I工具非随机研究评估偏倚风险。本综述包括30项研究,涉及6924例成人HNC患者。在30项研究中的26项(87%)中,治疗前的肌少症与较差的总体生存结果显着相关。在所有具有治愈意图的治疗方式中。男性最常见的性别特异性SMI截止值<52.4cm2/m2,女性<38.5cm2/m2。这篇综述的结果表明,肌少症是接受初级治愈性治疗的HNC患者总体生存的重要预后因素。肌肉减少症评估似乎是HNC人群中良好的预后指标。未来的营养干预研究可能集中在逆转肌肉损失和改善确定的肌少症个体的总体结果。
    The aim of this study was to determine the prognostic value of pre-treatment sarcopenia, defined radiologically (cervical (C3) or lumbar (L3) region), in adult head and neck cancer (HNC) patients undergoing treatment with curative intent. A systematic search of the PubMed and Scopus databases was performed up to March 2024. Inclusion criteria were adult patients with locally advanced HNC, sarcopenia defined radiologically at the C3 and/or L3 level, and patients receiving primary treatment with curative intent. Risk of bias was assessed using the ROBINS-I tool non-randomised studies. Thirty studies involving a total of 6924 adult patients with HNC were included in this review. Pre-treatment sarcopenia was significantly associated with worse overall survival outcomes in 26 of the 30 studies (87%), across all treatment modalities with curative intent. The most frequent sex-specific SMI cut-off values were <52.4 cm2/m2 for males and <38.5 cm2/m2 for females. The findings of this review suggest that sarcopenia is a strong prognostic factor of overall survival in HNC patients undergoing primary curative treatment. Sarcopenia evaluation appears to be a good prognostic marker in the HNC population. Future nutritional interventional studies might focus on reversing the muscle loss and improving overall outcomes in identified sarcopenic individuals.
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  • 文章类型: Journal Article
    两相渗流流体(即,由于缺乏准确且具有代表性的内部孔隙结构模型,因此尚未对原状花岗岩残积土(U-GRS)中的空气和水)行为进行全面研究。通过利用X射线计算机断层扫描(CT)以及由Shan-Chen模型增强的晶格玻尔兹曼方法(LBM),本研究模拟了U-GRS内部孔隙特征对水-气两相渗流行为的影响。我们的发现表明,这种流体倾向于更大、更直的渗流通道,随着渗漏的进展,水/气相的体积分数表现出最初的增加/减少趋势,最终稳定下来。结果表明,两相渗流速度对孔隙度的依赖性,而局部渗流速度受孔隙结构分布和复杂性的影响。这强调了在研究原状土壤中的两相流时需要考虑孔隙分布和连通性。观察到残余气相在孔隙空间内持续存在,主要位于孔隙边缘和死区。此外,这项研究发现,疏水壁排斥相邻的流体,从而加速流体运动,而亲水壁吸引液体,诱导减缓流体流动的粘性效应。因此,发现两相流速随着随后增强的疏水性而增加。在疏水壁条件下观察到水相体积分数的顶点,达到96.40%,残余气相占3.60%。亲水壁比中性壁保留更多的残余气相体积分数,其次是疏水壁。最后,X射线CT和LBM的研究表明,孔隙结构特征和孔壁的润湿性显着影响两相渗流过程。
    The two-phase seepage fluid (i.e., air and water) behaviors in undisturbed granite residual soil (U-GRS) have not been comprehensively studied due to a lack of accurate and representative models of its internal pore structure. By leveraging X-ray computed tomography (CT) along with the lattice Boltzmann method (LBM) enhanced by the Shan-Chen model, this study simulates the impact of internal pore characteristics of U-GRS on the water-gas two-phase seepage flow behaviors. Our findings reveal that the fluid demonstrates a preference for larger and straighter channels for seepage, and as seepage progresses, the volume fraction of the water/gas phases exhibits an initial increase/decrease trend, eventually stabilizing. The results show the dependence of two-phase seepage velocity on porosity, while the local seepage velocity is influenced by the distribution and complexity of the pore structure. This emphasizes the need to consider pore distribution and connectivity when studying two-phase flow in undisturbed soil. It is observed that the residual gas phase persists within the pore space, primarily localized at the pore margins and dead spaces. Furthermore, the study identifies that hydrophobic walls repel adjacent fluids, thereby accelerating fluid movement, whereas hydrophilic walls attract fluids, inducing a viscous effect that decelerates fluid flow. Consequently, the two-phase flow rate is found to increase with then-enhanced hydrophobicity. The apex of the water-phase volume fraction is observed under hydrophobic wall conditions, reaching up to 96.40%, with the residual gas-phase constituting 3.60%. The hydrophilic wall retains more residual gas-phase volume fraction than the neutral wall, followed by the hydrophobic wall. Conclusively, the investigations using X-ray CT and LBM demonstrate that the pore structure characteristics and the wettability of the pore walls significantly influence the two-phase seepage process.
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