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Advances in radiation protection related to pediatric chest computed tomography examinations
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作者 Qing-Ting Sun Yi-Han Fan Bao-Hui Liang 《World Journal of Radiology》 2025年第7期49-58,共10页
With the rapid development of computed tomography(CT)technology,the widespread use of CT examinations in the evaluation of chest diseases in pediatrics has raised extensive concerns about radiation issues.This review ... With the rapid development of computed tomography(CT)technology,the widespread use of CT examinations in the evaluation of chest diseases in pediatrics has raised extensive concerns about radiation issues.This review first systematically summarizes the factors influencing radiation dose(detector,tube voltage,tube current-time product,field of view,and reconstruction algorithms)in pediatric chest computed tomography examinations.Methods to reduce radia-tion dose are also discussed,including the utilization of filters,automatic tube current modulation,automatic tube voltage selection,and organ dose modulation.Finally,the methods for individualized radiation dose calculation in pediatric chest CT examinations:effective dose,CT dosimetry software,Size-Specific Dose Estimate,and the Monte Carlo method are reviewed.Radiation exposure re-duction is a multifaceted issue.This review aims to provide an optimal scanning scheme for pediatric chest CT from different perspectives. 展开更多
关键词 Chest computed tomography Radiation dose PEDIATRIC size-specific dose estimate Monte Carlo
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Non-metallic gold nanoclusters for oxygen activation and aerobic oxidation 被引量:2
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作者 Guomei Zhang Ruru Wang Gao Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第5期687-693,共7页
In recent decade, Au nanoclusters of atomic precision (AunLm, where L= organic ligand: thiolate andphosphine) have been shown as a new promising nanogold catalyst. The well-defined AunLm catalystspossess unique ele... In recent decade, Au nanoclusters of atomic precision (AunLm, where L= organic ligand: thiolate andphosphine) have been shown as a new promising nanogold catalyst. The well-defined AunLm catalystspossess unique electronic properties and frameworks, providing an excellent opportunity to correlate theintrinsic catalytic behavior with the cluster's framework as well as to study the catalytic mechanismsover gold nanoclusters. In this review, we only demonstrate the important roles of the gold nanoclustersin the oxygen activation (e.g., 302 to 102) and their selective oxidations in the presence of oxygen (e.g., COto C02, sulfides to sulfoxides, alcohol to aldehyde, styrene to styrene epoxide, amines to imines, andglucose to gluconic acid). The size-specificity (Au25 (1.3 nm), Au38 (].5 nm), Au144 (1.9 nm), etc.), ligandengineering (e.g., aromatic vs aliphatic), and doping effects (e.g., copper, silver, palladium, and platinum)are discussed in details. Finally, the proposed reactions' mechanism and the relationships of clusters'structure and activity at the atomic level also are presented. 展开更多
关键词 Gold nanocluster Oxygen activation Aerobic oxidation size-specificity Ligand engineering Doping effects
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