Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Comparison study on seismic isolation design of RC frame structure based on two different codes

Zhang Junyi, Li Jiawei, Zhang Zhiqiang

Archives of Civil Engineering

2024

Vol. 70, nr 2

387--401

With the development of building seismic isolation technology and the official release of the Isolation Code in September 2021, seismic isolation design in China will now rely on two foundational codes: the Seismic Code and the Isolation Code. This paper take a ceramic jar storage of the RC frame structure as the research object, and carry out the seismic isolation design based on the separated calculation design method of the Seismic Code and the unitary calculation design method of the Isolation Code respectively, and clarify the control index of the Isolation Code is the story drift angle. The maximum displacement is reduced by 37.5%. In terms of material consumption, the Isolation Code leads to a 5.94% decrease in concrete usage, accompanied by a 13.97% increase in steel consumption, resulting in an overall cost increase of 4.98%. The findings indicate that seismic isolation design, guided by the Isolation Code, substantially mitigates the seismic response of the superstructure. The damage extent to structural members is reduced by 15-20%, promoting enhanced safety and repairability. The outcomes of this study offer valuable insights for future seismic isolation designs in RC frame structures.

Validation and quantification of a UPLC-MS/MS method for the simultaneous determination of quinocetone and its main metabolites (3-methylquinoxaline-2-carboxylic acid and dedioxoquinenone) in aquatic products

Tian Xiuhui, Han Dianfeng, Cui Yanmei, Ren Lihua, Jiang Fang, Huang Hui, Gong Xianghong, Xue Jinglin, Li Jiawei, Liu Huihui, Xu Yingjiang, Luo Xiaojun, Liu Xiaojing, Zhang Xiuzhen

Acta Chromatographica

2022

Vol. 34, no. 4

444--452

A sensitive and validated method for determining quinocetone and its main metabolites (3-methylquinoxaline-2-carboxylic acid and dedioxoquinenone) was established in aquatic products using ultra-high-performance liquid chromatography-tandem spectrometry (UHPLC-MS/MS). Samples were extracted with 2.0 mol L⁻¹ hydrochloric acid, then purified on MAX columns. After extraction and purification, the supernatant was evaporated to dry nearly under a gentle stream of nitrogen at 40 °C. Formic acid-acetonitrile-water (0.1/30/70, v/v/v) was adjusted to 1.00 mL final volume. An aliquot (10 μL) was injected into the C18 column for separation with the mobile phase of acetonitrile and 0.5% formic acid in water at 0.25 mL min⁻¹. Calibration curves were linear ranged from 10.00 ng mL⁻¹ to 200.0 ng mL⁻¹ for quinocetone and 3-methylquinoxaline-2-carboxylic acid, and 20.00 ng mL⁻¹ to 400.0 ng mL⁻¹ for dedioxoquinenone. Mean recoveries were 70%–89%, 73%–83% and 72%–84%, respectively. The limit of detection (LOD) was 1.00 μg kg⁻¹, 1.00 μg kg⁻¹ and 2.00 μg kg⁻¹, and quantification (LOQ) were 2.00 μg kg⁻¹, 2.00 μg kg⁻¹ and 4.00 μg kg⁻¹ for quinocetone, 3-methylquinoxaline-2-carboxylic acid, and dedioxoquinenone. Based on the method above, the analytes were determined in Apostichopus japonicus, three fishes (including Ctenopharyngodon idellus, Crucian carp and Oreochromis mossambicus), Penaeus vannamei, Penaeus chinensis, and Chlamys farreri. The method shows good sensitivity, linearity, precision, and accuracy. In short, the proposed method was reliable for the determination of quinocetone, 3-methylquinoxaline-2-carboxylic acid, and dedioxoquinenone in aquatic products.