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
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
基金Supported by the Key Natural Science Project of the Anhui Provincial Education Department Under,No.KJ2021A0746.
文摘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.
基金financial support by the Program for the Outstanding Innovative Teams of Higher Learning Institutions of Shanxi(OIT)Shanxi Province Hundred Talent Project
文摘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.