Carbon capture,utilization and storage (CCUS) is considered as a very important technology for mitigating global climate change.Carbon dioxide (CO2) injected into an underground reservoir will induce changes in its ph...Carbon capture,utilization and storage (CCUS) is considered as a very important technology for mitigating global climate change.Carbon dioxide (CO2) injected into an underground reservoir will induce changes in its physical properties and the migration of CO2 will be affected by many factors.Accurately understanding these changes and migration characteristics of CO2 is crucial for selecting a CCUS project site,estimating storage capacity and ensuring storage security.In this paper,the basic principles of nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) technologies are briefly introduced in the context of laboratory experiments related to CCUS.The types of NMR apparatus,experimental samples and testing approaches applied worldwide are discussed and analyzed.Then two typical NMR core analysis systems used in CCUS field and a self-developed high-pressure,low-field NMR rock core flooding experimental system are compared.Finally,a summary of the current deficiencies related to NMR applied to CCUS field is given and future research plans are proposed.展开更多
目的评价3.0 T MR扩散加权成像(DWI)及表观扩散系数(ADC值)对良、恶性泪腺上皮性肿瘤的诊断价值。材料与方法回顾性分析42例经手术病理证实的泪腺上皮性肿瘤常规MRI、DWI影像特点及ADC值,包括良性肿瘤17例,恶性肿瘤25例。所有病例选取b=...目的评价3.0 T MR扩散加权成像(DWI)及表观扩散系数(ADC值)对良、恶性泪腺上皮性肿瘤的诊断价值。材料与方法回顾性分析42例经手术病理证实的泪腺上皮性肿瘤常规MRI、DWI影像特点及ADC值,包括良性肿瘤17例,恶性肿瘤25例。所有病例选取b=0、1000 s/mm2 DWI序列,测量病灶扩散受限最显著区的ADC值并做统计学分析,良恶性肿瘤的ADC值比较采用Mann-Whitney U检验,并绘制ADC值诊断良恶性泪腺上皮性肿瘤的受试者工作特征(ROC)曲线。结果 42例肿瘤的平均ADC值为(0.965±0.191)×10-3 mm2/s,良性及恶性肿瘤的平均ADC值分别为:(1.142±0.096)×10-3 mm2/s及(0.845±0.140)×10-3 mm2/s,两者之间的ADC值差异具有统计学意义(Z=-4.754,P=0.000<0.01)。恶性泪腺上皮性肿瘤的扩散受限最显著区ADC值低于良性。ROC曲线下面积S=0.936±0.043,S>0.9,利用ADC值鉴别诊断肿瘤良、恶性的准确度较高。以ADC≤0.968×10-3mm2/s作为鉴别良、恶性泪腺上皮性肿瘤的诊断界值,诊断恶性肿瘤的灵敏度为92%,特异度为94%,准确度93%。结论 3.0 T DWI可以揭示泪腺上皮性肿瘤的扩散特征,有助于良、恶性泪腺上皮性肿瘤的鉴别诊断;通过对ADC值进行定量分析,为泪腺良、恶性上皮性肿瘤的鉴别诊断提供客观依据。展开更多
基金supported by the Open Research Fund of State Key Laboratory of Geomechanics and GeotechnicalEngineering, IRSM, CAS (Grant No. Z017002)the National Natural Science Foundation of China (Grant Nos. 41872210 and 41274111)financial support from the China-Australia Geological Storage of CO_2 (CAGS) Project funded by the Australian Government under the auspices of the China-Australia Joint Coordination Group on Clean Coal Technology
文摘Carbon capture,utilization and storage (CCUS) is considered as a very important technology for mitigating global climate change.Carbon dioxide (CO2) injected into an underground reservoir will induce changes in its physical properties and the migration of CO2 will be affected by many factors.Accurately understanding these changes and migration characteristics of CO2 is crucial for selecting a CCUS project site,estimating storage capacity and ensuring storage security.In this paper,the basic principles of nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) technologies are briefly introduced in the context of laboratory experiments related to CCUS.The types of NMR apparatus,experimental samples and testing approaches applied worldwide are discussed and analyzed.Then two typical NMR core analysis systems used in CCUS field and a self-developed high-pressure,low-field NMR rock core flooding experimental system are compared.Finally,a summary of the current deficiencies related to NMR applied to CCUS field is given and future research plans are proposed.
