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基于CFD的多级轴流风机动静干涉及激励特性研究
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作者 朱程康 李诗徉 +2 位作者 叶豪杰 蒋洪涛 吴大转 《风机技术》 2024年第5期1-6,共6页
为了探究多级轴流风机的动静干涉及激励特性,分析每级叶轮不同相位排布对风机气动性能和流场激励的影响,对五级一体化轴流风机模型进行数值模拟。分别改变每级叶轮的相位排布角度为0°、2°、4°、6°,获得轴流风机内... 为了探究多级轴流风机的动静干涉及激励特性,分析每级叶轮不同相位排布对风机气动性能和流场激励的影响,对五级一体化轴流风机模型进行数值模拟。分别改变每级叶轮的相位排布角度为0°、2°、4°、6°,获得轴流风机内部流场和性能参数以及每级叶轮受力情况。结果表明:随着排布角度增大,叶轮对流体挤压增大,后半段流场流动恶化,效率约下降2.1%。每级叶轮受力的主要特征频率为叶频(fBPF)及其倍频,且幅值随频率增加而快速减小。同时,排布角度对每级叶轮受力的影响也体现在流场性能和流体能量上,越稳定的流场,其特征频率越集中且振幅较高。 展开更多
关键词 多级轴流风机 相位角度 数值计算 气动性能 流动激励 动静干涉
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抗VEGF综合治疗对新生血管性青光眼的疗效 被引量:12
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作者 张小牛 李世洋 肖建和 《国际眼科杂志》 CAS 北大核心 2020年第2期243-246,共4页
目的:观察联合抗VEGF药物的综合治疗对新生血管性青光眼(NVG)的疗效。方法:回顾性分析2012-02/2018-10在我院就诊的NVG患者62例68眼的临床资料,A组先行玻璃体腔注射抗VEGF药物,术后1wk行复合式小梁切除术,术后3wk行全视网膜激光;B组行... 目的:观察联合抗VEGF药物的综合治疗对新生血管性青光眼(NVG)的疗效。方法:回顾性分析2012-02/2018-10在我院就诊的NVG患者62例68眼的临床资料,A组先行玻璃体腔注射抗VEGF药物,术后1wk行复合式小梁切除术,术后3wk行全视网膜激光;B组行睫状体冷凝术。观察两组患者治疗前和治疗后2wk,1、3、6mo的眼压、最佳矫正视力(BCVA)、眼轴和并发症等。结果:A组虹膜新生血管的消退程度优于B组。两组患者术后2wk,1、3、6mo眼压比较有差异(P<0.05),且治疗后6mo眼轴长度有差异(P<0.05)。A组总有效率为94%,B组总有效率为78%(P=0.073)。结论:NVG接受抗VEGF药物+复合式小梁切除术+全视网膜激光光凝治疗安全有效。 展开更多
关键词 新生血管性青光眼 抗VEGF治疗 玻璃体腔注射 小梁切除术 睫状体冷凝术
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Endoscopic and pathological characteristics of de novo colorectal cancer:Retrospective cohort study 被引量:2
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作者 shi-yang li Mei-Qi Yang +2 位作者 Yi-Ming liu Ming-Jun Sun Hui-Jing Zhang 《World Journal of Gastroenterology》 SCIE CAS 2023年第18期2836-2849,共14页
BACKGROUND Endoscopy has rapidly developed in recent years and has enabled further investigation into the origin and features of intestinal tumors.The small size and concealed position of these tumors make it difficul... BACKGROUND Endoscopy has rapidly developed in recent years and has enabled further investigation into the origin and features of intestinal tumors.The small size and concealed position of these tumors make it difficult to distinguish them from nonneoplastic polyps and carcinoma in adenoma(CIA).The invasive depth and metastatic potential determine the operation regimen,which in turn affects the overall survival and distant prognosis.The previous studies have confirmed the malignant features and clinicopathological features of de novo colorectal cancer(CRC).AIM To provide assistance for diagnosis and treatment,but the lack of a summary of endoscopic features and assessment of risk factors that differ from the CIA prompted us to conduct this retrospective study.METHODS In total,167 patients with small-sized CRCs diagnosed by endoscopy were reviewed.The patients diagnosed as advanced CRCs and other malignant cancers or chronic diseases that could affect distant outcomes were excluded.After screening,63 cases were excluded,including 33 de novo and 30 CIA cases.Patient information,including their follow-up information,was obtained from an electronic His-system.The characteristics between two group and risk factors for invasion depth were analyzed with SPSS 25.0 software.RESULTS Nearly half of the de novo CRCs were smaller than 1 cm(n=16,48.5%)and the majority were located in the distal colon(n=26,78.8%).The IIc type was the most common macroscopic type of de novo CRC.In a Pearson analysis,the differential degree,Sano,JNET,and Kudo types,surrounding mucosa,and chicken skin mucosa(CSM)were correlated with the invasion depth(P<0.001).CSM was a significant risk factor for deep invasion and disturbed judgment of endoscopic ultrasound.A high degree of tumor budding and tumor-infiltrating lymphocytes are accompanied by malignancy.Finally,de novo CRCs have worse outcomes than CIA CRCs.CONCLUSION This is the first comprehensive study to analyze the features of de novo CRCs to distinguish them from nonneoplastic polyps.It is also the first study paying attention to CSM invasive depth measurement.This study emphasizes the high metastatic potential of de novo CRCs and highlights the need for more research on this tumor type. 展开更多
关键词 De novo colorectal cancer Carcinoma in adenoma Endoscopic features Clinical characteristics Pathological features
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Shotfile切削模式治疗近视伴老视患者的远期临床疗效 被引量:1
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作者 胡萌菲 李世洋 +3 位作者 邢星 马红利 赵爱红 刘雪雁 《国际眼科杂志》 CAS 北大核心 2018年第1期192-194,共3页
目的:评价Shotfile老视切削模式治疗近视伴老视患者的远期临床疗效。方法:对我院43例82眼35岁及以上近视屈光不正患者行激光角膜手术,采用Shotfile老视切削模式,随访3a。观察术后1、2、3a时的裸眼远、近视力和屈光度变化、视觉满意度情... 目的:评价Shotfile老视切削模式治疗近视伴老视患者的远期临床疗效。方法:对我院43例82眼35岁及以上近视屈光不正患者行激光角膜手术,采用Shotfile老视切削模式,随访3a。观察术后1、2、3a时的裸眼远、近视力和屈光度变化、视觉满意度情况。结果:术后1a裸眼远视力达到术前最佳矫正视力者81眼(99%),裸眼近视力在0.66以上者75眼(91%),等效球镜平均为-0.64±0.63D,总体满意率为91%;术后2a裸眼远视力达到术前最佳矫正视力者79眼(96%),裸眼近视力在0.66以上者69眼(84%),等效球镜平均为-0.62±0.59D,总体满意率为86%;术后3a裸眼远视力达到术前最佳矫正视力者77眼(94%),裸眼近视力在0.66以上者62眼(76%),等效球镜平均为-0.55±0.56D,总体满意率为81%。所有入选病例均未出现术中或术后严重并发症,1眼等效球镜为-10.00D的患者1a后出现-1.75D的回退,尊重患者意愿为患者进行二次补矫。结论:Shotfile老视切削模式治疗近视伴老视患者远期疗效安全稳定,患者满意度较高,随时间延长部分患者视近能力逐渐减弱,术前应与患者进行充分沟通。 展开更多
关键词 Shotfile老视切削模式 近视伴老视 激光角膜手术 远期疗效
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Design of an ultrasonic motor with multi-vibrators 被引量:2
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作者 Chong li Cun-yue LU +2 位作者 Yi-xin MA shi-yang li Wei-qing HUANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2016年第9期724-732,共9页
This paper presents and verifies a new idea for constructing an ultrasonic motor (USM). The stator contains several vibrators fabricated by bonding piezoelectric ceramics (PZTs) to a metal base. When two alternati... This paper presents and verifies a new idea for constructing an ultrasonic motor (USM). The stator contains several vibrators fabricated by bonding piezoelectric ceramics (PZTs) to a metal base. When two alternating current (AC) voltages with a 90° phase difference are applied to the PZTs, longitudinal and bending modes are excited in the vibrator. The bending vibrations of the vibrators are stacked to form the torsional vibration of the stator, ultimately generating longitudinal-torsional composite vibration. Both vibrators and the stator are excited to the resonance state. A standing wave is formed by superposition of longitudinal and torsional modes. The proposed motor is an in-plane vibration motor because the vibrations of the stator are in the circumferential plane. The finite element method (FEM) is used to validate the feasibility of the proposed motor. The fabricated stator contains five vibrators. The tested resonance frequencies of longitudinal and torsional modes are 44.42 kHz and 43.83 kHz, respectively. The stall torque is 0.3 N'm and no-load speed is 45 r/min. The highest efficiency is 30%. The applied driving voltage is 100 Vo.p (peak voltage) at 43.9 kHz. The designed motor is a parallel-actuated integral motor. It allows the vibrators to operate synchronously, and overcomes asynchronous issues that occur in traditional multi-vibrator motors. 展开更多
关键词 Ultrasonic motor (USM) Standing wave In-plane vibration Multi-vibrator
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Recent progress in organic hole-transporting materials with 4-anisylamino-based end caps for efficient perovskite solar cells 被引量:2
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作者 Xiao-Peng Xu shi-yang li +1 位作者 Ying li Qiang Peng 《Rare Metals》 CSCD 2021年第7期1669-1690,共22页
Perovskite solar cells(PVSCs)have emerged as a promising photovoltaic technology and have attracted wide research interest due to their outstanding photovoltaic performance,low cost,and the ability to fabricate largea... Perovskite solar cells(PVSCs)have emerged as a promising photovoltaic technology and have attracted wide research interest due to their outstanding photovoltaic performance,low cost,and the ability to fabricate largearea devices.An impressive certified power conversion efficiency(PCE)of 25.2%has been achieved,demonstrating the excellent potential of PVSCs for future applications.Hole-transporting materials play a key role in improving the device performance of PVSCs by facilitating the extraction of photogenerated holes and their transport from the perovskite layer to the anode.This review provides a brief introduction to PVSCs and summarizes the recent progress in small molecule hole-transporting materials(SM-HTMs)bearing various cores and different4-anisylamino-based end caps.We classify the end caps into N,N-di-4-anisylamino(DAA),4-(N,N-di-4-anisylamino)benzo(DAB),and N3,N6(or N2,N7)-bis(di-4-anisylamino)-9 H-carbazole(3,6-DAC or 2,7-DAC)groups.We also review the core type,end cap position and number,how these affect the overall properties of the SM-HTMs,and the resultant PVSC device performances.Finally,the challenges and perspectives for the future development of SM-HTMs are presented. 展开更多
关键词 Perovskite solar cells Hole-transporting materials Small molecules 4-Anisylamino derivatives
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