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船舶结构边界条件下多气泡脉动特性

山东交通学院学报 2024年第2期32卷 116-122页

作者：龚月滢于福临苏超郭文琦李战全阮雨李庆海山东交通学院船舶与港口工程学院山东威海264200 威海市流固耦合动力学重点实验室山东威海264200

为研究多气泡在船舶壁面结构附近的脉动特性,采用400 V水下低压放电生成气泡技术,通过超高速摄像机记录水下气泡的脉动过程。在气泡距壁面适当距离下,在水平壁面下方水平布置或垂向布置2个气泡,在V型结构壁面两侧对称水平布置2个气泡,... 详细信息

为研究多气泡在船舶壁面结构附近的脉动特性,采用400 V水下低压放电生成气泡技术,通过超高速摄像机记录水下气泡的脉动过程。在气泡距壁面适当距离下,在水平壁面下方水平布置或垂向布置2个气泡,在V型结构壁面两侧对称水平布置2个气泡,在不同的气泡与壁面距离、2个气泡间距下分析多气泡耦合脉动特性。试验结果表明:不同边界条件下2个气泡的耦合特性不同;水平壁面下方垂向布置的2个气泡融合后出现颈缩现象,产生的射流穿透气泡后冲击到壁面,壁面承受冲击力;水平壁面下方水平布置的2个气泡融合后产生斜向上的射流,射流相撞,最终冲击到壁面上,对壁面造成损伤;V型结构壁面下水平布置2个气泡,耦合后产生指向对方和V型结构的射流,射流在气泡中间相撞,气泡断裂,射流对V型结构的冲击较小。

关键词：水下爆炸多气泡 V型结构气泡脉动

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层冰边界条件下多气泡破冰试验研究

山东交通学院学报 2024年第3期32卷 104-111页

作者：李庆海于福临郭文琦苏超李战全贾风光龚月滢山东交通学院船舶与港口工程学院山东威海264200 威海市船舶流固耦合动力学重点实验室山东威海264200

为提高破冰船的破冰能力,探究气泡运动状态和特征参数对层冰的影响规律,在一定的气泡间距和气泡与层冰距离条件下,通过超高速摄像机研究在层冰下方布置单个气泡、水平布置2个气泡、垂直布置2个气泡的运动状态、半径变化及其破冰效果。... 详细信息

为提高破冰船的破冰能力,探究气泡运动状态和特征参数对层冰的影响规律,在一定的气泡间距和气泡与层冰距离条件下,通过超高速摄像机研究在层冰下方布置单个气泡、水平布置2个气泡、垂直布置2个气泡的运动状态、半径变化及其破冰效果。研究结果表明:带孔层冰下方布置单个气泡时,气泡塌陷后形成冲击波,在层冰的上、下表面形成膨胀波和压缩波,导致层冰自上向下破裂;无孔层冰下方水平布置2个距离过近的气泡,相互融合后坍塌,形成斜射流后释放冲击波,传播到层冰的上、下表面,导致层冰自下向上破裂;带孔层冰下方水平布置2个距离较近的气泡时,气泡融合后坍塌,形成朝下的斜射流,射流碰撞后形成冲击波,导致层冰自下向上破裂;带孔层冰下方垂直布置2个距离较近的气泡时,气泡相互融合后收缩,形成向下的射流,射流碰撞产生水锤效应,产生冲击波传播到层冰表面产生反射波,导致层冰自下向上破裂。气泡与带孔层冰相互作用的破冰效果弱于无孔层冰。

关键词：层冰边界气泡破冰效果射流冲击波

Hyperbranched polymer hollow-fiber-composite membranes for pervaporation separation of aromatic/aliphatic hydrocarbon mixtures

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Chinese Journal of Chemical Engineering 2024年第5期69卷 13-22页

作者： Tong liu Hao Sun Xiangqiong Wang Jie li zhanquan Zhang Pei Wu Naixin Wang Quanfu An Beijing Key Laboratory for Green Catalysis and Separation Department of Chemical EngineeringCollege of Materials Science and EngineeringBeijing University of TechnologyBeijing 100124China Petrochemical Research Institute CNPCBeijing 102206China

The separation of aromatic/aliphatic hydrocarbon mixtures is crucial in the petrochemical *** is regarded as a promising approach for the separation of aromatic compounds from alkanes. Developing membrane materials with efficient separation performance is still the main task since the membrane should provide chemical stability, high permeation flux, and selectivity. In this study, the hyperbranched polymer(HBP) was deposited on the outer surface of a polyvinylidene fluoride(PVDF)hollow-fiber ultrafiltration membrane by a facile dip-coating method. The dip-coating rate, HBP concentration, and thermal cross-linking temperature were regulated to optimize the membrane *** obtained HBP/PVDF hollow-fiber-composite membrane had a good separation performance for aromatic/aliphatic hydrocarbon mixtures. For the 50%/50%(mass) toluene/n-heptane mixture, the permeation flux of optimized composite membranes could reach 1766 g·m^(-2)·h^(-1), with a separation factor of 4.1 at 60℃. Therefore, the HBP/PVDF hollow-fiber-composite membrane has great application prospects in the pervaporation separation of aromatic/aliphatic hydrocarbon mixtures.

关键词： Aromatic/aliphatic hydrocarbons Hyperbranched polymer Pervaporation Hollow fiber membrane Dip-coating

基于Welch功率谱的加速度积分改进方法研究

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振动与冲击 2022年第18期41卷 41-46,54页

作者：李展铨陈太聪华南理工大学土木与交通学院广州510641 亚热带建筑科学国家重点实验室广州510641 琶洲实验室广州510335

针对带噪加速度信号的积分问题,新近发展的有效频段法相对于传统的频率截止法,积分精度和抗噪性得到了较大改善。但多个分析频率范围需要人为指定,且高噪声的适应性仍较差,不利于工程实践。基于加速度信号的Welch功率谱,提出改进的有效... 详细信息

针对带噪加速度信号的积分问题,新近发展的有效频段法相对于传统的频率截止法,积分精度和抗噪性得到了较大改善。但多个分析频率范围需要人为指定,且高噪声的适应性仍较差,不利于工程实践。基于加速度信号的Welch功率谱,提出改进的有效频段法。首先针对Welch功率谱曲线,综合应用5%峰值阈值和邻近波谷频率,实现分析频率范围的自动定义。继而提出基于Welch功率谱曲线和基于Welch功率谱开方曲线的两种不同形态拟合方法,实现有效频段的自动识别。最终进行有效频段内的频域积分,得到相应的速度和位移信号。通过数值模拟算例,对比考察原有效频段法和改进方法在多频激励和随机激励下的积分效果。结果表明,相对于原方法,改进方法可以实现加速度积分的全程自动分析,且抗噪性能进一步加强,其中基于Welch功率谱曲线和基于Welch功率谱开方曲线的形态拟合分别适用于高噪声下的多频激励情况和随机激励情况。

关键词：加速度积分频域积分有效频段 Welch功率谱

Cardiac autonomic nerve fiber regeneration in chronic heart failure Do Akt gene-transduced mesenchymal stem cells promote repair?

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Neural Regeneration Research 2010年第1期5卷 28-34页

作者： Hongliang Kong zhanquan li Shumei Zhao li Zhu Yingjun Zhao Weiwei Zhang GuipingXu Wenjun Hao Huijun li Guoxian Qi Department of Cardiology the First Affiliated Hospital of China Medical University Shenyang 110001 Liaoning Province China Department of Cardiology the People's Hospital of Liaoning Province Shenyang 110016 Liaoning Province China Shenyang Normal University Shenyang 110034 Liaoning Province China

BACKGROUND： Transplantation of Akt-over-expressing mesenchymal stem ceils （Akt-MSCs） has been shown to repair infarcted myocardium and improve cardiac function. However, little is known about the therapeutic effects of Akt-MSCs on cardiac autonomic neuropathy in chronic heart failure （CHF）. OBJECTIVE： The present study used adriamycin-induced CHF rat models to observe the effect of Akt-MSCs on cardiac autonomic nervous regeneration and the factors mediating this effect. DESIGN, TIME AND SETTING： A randomized, controlled animal experiment was performed at the Central Laboratory of Basic Medical College, China Medical University, between September 2008 and April 2009. MATERIALS： Rabbit anti-choline acetyltransferase （CHAT）, growth associated protein-43 （GAP-43） synaptophysin （SYN） polyclonal antibodies and the secondary antibody （goat anti-rabbit IgG） were purchased from Boster, China. Cat-A-Kit assay system was provided by Amersham, USA. METHODS：（1） Adult rat MSCs were isolated and cultured for the preparation of Akt-MSCs. （2） Forty male Wistar rats were intramyocardially administered adriamycin at 2 mg/kg over 3 days for a total of five times and once a week for additional five times thereafter to establish CHF models. At 2 weeks after final adriamycin treatment, 34 successful CHF rat models were randomized to three groups： Akt-MSCs （n = 11）, simple MSCs （s-MSCs, n =11）, and control （n = 12）. Each group was intravenously administered Akt-MSCs （2x106 cells in 100 IJL PBS）, s-MSCs （2×10^6 cells in 100 μL PBS） or equal volume of phosphate buffered saline, once a day for a total of three times. MAIN OUTCOME MEASURES： At 4 weeks after final adriamycin treatment, myocardial norepinephrine （NE） content was detected using a Cat-A-Kit assay system. Myocardial CHAT, SYN and GAP-43 were performed by immunohistochemistry and Western blot analysis. Prior to, 2 and 4 weeks after adriamycin treatment, echocardiographic examination was performed and left ventricular ejection fract

关键词： mesenchymal stem cells Akt gene transfection chronic heart failure neural regeneration autonomic nerve system

光响应基因BcCfaS通过脂质代谢调控灰葡萄孢菌的光形态建成及致病力

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Engineering 2024年第4期35卷 201-213页

作者： Guangjin li zhanquan Zhang Yong Chen Tong Chen Boqiang li Shiping Tian Key Laboratory of Plant Resources The Innovative Academy of Seed DesignInstitute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China

light is a fundamental environmental factor for living organisms on earth—not only as a primary energy source but also as an informational *** fungi,light can be used as an indicator for both time and space to control important physiological and morphological *** cinerea(***)is a devastating phytopathogenic fungus that exploits light cues to optimize virulence and the balance between conidiation and sclerotia development,thereby improving its dispersal and survival in ***,the components and mechanisms underlying these processes remain ***,we identify a novel light-signaling component in ***,BcCfaS,which encodes a putative cyclopropane fatty-acyl-phospholipid *** is strongly induced by light at the transcriptional level and plays a crucial role in regulating *** of BcCfaS results in reduced vegetative growth,altered colony morphology,impaired sclerotial development,and enhanced conidiation in a lightdependent ***,the mutant exhibits serious defects in stress response and virulence on the *** on a lipidomics analysis,a number of previously unknown fungal lipids and many BcCfaS-regulated lipids are identified in ***,including several novel phospholipids and fatty ***,we find that BcCfaS controls conidiation and sclerotial development by positively regulating methyl jasmonate(MeJA)synthesis to activate the transcription of light-signaling components,revealing for the first time the metabolic base of photomorphogenesis in ***,we propose that BcCfaS serves as an integration node for light and lipid metabolism,thereby providing a regulatory mechanism by which fungi adapt their development to a changing light *** new findings provide an important target for antifungal design to prevent and control fungal disease.

关键词： light Botrytis cinerea Cyclopropane fatty-acyl-phospholipid synthase lipid metabolism Photomorphogenesis Virulence

Novel completed biodegradable polymer sirolimus-eluting stent versus durable polymer sirolimus-eluting stent in de novo lesions： nine-month angiographic and three-year clinical outcomes of HOPE trial

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Chinese Medical Journal 2014年第14期127卷 2561-2566页

作者： Yuan Fei Chen Xin Song Xiantao Wang Dongqi Zhang Zheng li Weimin li zhanquan li Hui Chen Xinyi Huo Yong Wang Lefeng Lu Caiyi Lu Qinghua Xu Bo li Wei Lyu Shuzheng Capital Med Univ Dept Cardiol Beijing Anzhen Hosp Beijing 100029 Peoples R China Xi An Jiao Tong Univ Dept Cardiol Affiliated Hosp 1 Xian 710061 Shaanxi Peoples R China Lanzhou Univ Dept Cardiol Affiliated Hosp 1 Lanzhou 730000 Gansu Peoples R China Harbin Med Univ Dept Cardiol Affiliated Hosp 1 Harbin 150001 Heilongjiang Peoples R China Peoples Hosp liaoning Prov Dept Cardiol Shenyang 110016 Liaoning Peoples R China Gen Hosp Daqing Oilfield Dept Cardiol Daqing 163411 Heilongjiang Peoples R China Peoples Hosp Shaanxi Prov Dept Cardiol Xian 710068 Shaanxi Peoples R China Peking Univ Dept Cardiol Hosp 1 Beijing 100044 Peoples R China Capital Med Univ Dept Cardiol Chaoyang Hosp Being 100020 Peoples R China Chinese Peoples liberat Army Gen Hosp Dept Cardiol Beijing 100853 Peoples R China Shandong Univ Dept Cardiol Hosp 2 Jinan 250033 Shandong Peoples R China Chinese Acad Med Sci Cardiac Catheterizat Lab Cardiovasc Inst Beijing 100037 Peoples R China Chinese Acad Med Sci Fuwai Hosp Beijing 100037 Peoples R China Peking Union Med Coll Beijing 100037 Peoples R China Natl Ctr Cardiovasc Dis China Beijing 100037 Peoples R China

Background Drug-eluting stents（DES） with durable polymer have significantly reduced restenosis and target vessel revascularization compared with bare metal stents. Durable polymer has been linked with persistent inflammation of vessel wall and delayed endothelial healing that may increase the risk of late and very late stent thrombosis. This study sought to evaluate the efficacy and safety of HELLOS completed biodegradable polymer sirolimus-eluting stent （SES） in de novo coronary *** Totally, 287 patients with one or two de novo coronary lesions （lesion length ≤38 mm and reference vessel diameter 2.5-4.0 mm） were enrolled in the HOPE study, a prospective, multicenter, randomized, non-inferiority trial. Patients were randomized to treatment either with HEliOS completed biodegradable polymer SES （n=142） or PARTNER durable polymer SES （n=145）. The primary endpoint was angiographic in-stent late lumen loss （LLL） at 9-month follow-up. The secondary endpoint included stent thrombosis and major adverse cardiac events including cardiac death, myocardial infarction （MI） and target lesion revascularization （TLR）.Results The 9-month in-stent LLL in the HEliOS group was similar to the PARTNER group, （0.16±0.22） mm vs. （0.19±0.30） mm （P=0.28）. The difference and 95% confidence interval were -0.03 （-0.09, 0.04）, and the P value for non-inferiority 〈0.01. Major adverse cardiovascular event （MACE） occurred in 7.9% vs. 8.2%, MI in 2.4% vs. 3.0%, TLR in 5.5% vs. 3.0%, and stent thrombosis in 0 vs. 1.5%; and events were comparable between the HEliOS group and PARTNER aroup at three-year follow-up （all P 〉0.05）. The three-year cardiac death was lower in the HEliOS group, butwith no significant difference, 0 vs. 3.0% （P=0.12）. Conclusions In the HOPE trial, the novel completed biodegradable polymer SES HEliOS was non-inferior to the durable polymer SES PARTNER with respect to nine-month in-stent LLL in de novo coronary lesions. The incidence of other clinical endpoints was l

关键词： biodegradable polymer titanium oxides films drug-eluting stents

肥胖儿童青少年每日步数与减脂效果的剂量效应关系

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中国学校卫生 2022年第9期43卷 1329-1332页

作者：陈泽恺朱琳李展权广州体育学院研究生院广东510500 广州体育学院运动与健康学院

目的探究肥胖儿童青少年每日不同步数与减脂效果间是否存在非线性关系和阈值效应,以期为肥胖儿童青少年的运动减脂提供科学精准的理论依据。方法2021年7—8月,在深圳减肥达人训练营招募48名10~17岁肥胖儿童青少年进行4周封闭式运动训练... 详细信息

目的探究肥胖儿童青少年每日不同步数与减脂效果间是否存在非线性关系和阈值效应,以期为肥胖儿童青少年的运动减脂提供科学精准的理论依据。方法2021年7—8月,在深圳减肥达人训练营招募48名10~17岁肥胖儿童青少年进行4周封闭式运动训练,使用ActiGraph GT3X+监控每日步数,通过干预前后身体成分指标的变化评价减脂效果。干预前后指标的比较使用配对样本t检验;每日步数与减脂效果间的剂量-效应关系使用线性回归及分段回归分析,非线性关系的分析使用限制性立方样条(RCS)分析。结果干预后体脂肪量(27.50±7.33)kg、体脂百分比(36.17±5.59)%、瘦体重(47.55±6.48)kg、骨骼肌量(26.14±3.84)kg较干预前[(31.97±7.82)kg,(39.06±5.12)%,(49.08±6.93)kg,(27.08±4.15)kg]均下降(t值分别为21.04,13.32,7.65,8.35,P值均<0.05),每日步数与以上指标的变化量间存在非线性剂量-效应关系(P值均<0.05);分段回归结果显示,校正年龄、性别和基线BMI后,每日步数每增加1000步,体脂肪量增加0.44(95%CI=0.03~0.84)kg、体脂百分比增加0.61%(95%CI=0.17%~1.04%)。在校正了年龄、性别、基线BMI后,当每日步数8300~11400时,每日步数每增加1000步,瘦体重增加0.58(95%CI=0.11~1.04)kg、骨骼肌量增加0.29(95%CI=0.03~0.54)kg。结论肥胖儿童青少年每日步数与减脂效果间存在非线性的剂量-效应关系,为了达到最佳减脂效率,每日步数以8300~11400步为宜。

关键词：肥胖症步行脂肪组织干预性研究儿童青少年

奖惩敏感性问卷的汉化及其在青少年中的信效度检验

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中国儿童保健杂志 2023年第9期31卷 980-985页

作者：李展权朱琳陈泽恺广州体育学院研究生院广东广州510500 广州体育学院运动与健康学院

目的对奖惩敏感性问卷(SPSRQ)进行汉化修订,并检验其在青少年中的信效度,以期为评估青少年奖惩敏感性提供可靠工具。方法对SPSRQ进行翻译、回译、跨文化调试,形成青少年SPSRQ中文版(SPSRQ-A);2022年1月17日—9月30日采用随机抽样法和年... 详细信息

目的对奖惩敏感性问卷(SPSRQ)进行汉化修订,并检验其在青少年中的信效度,以期为评估青少年奖惩敏感性提供可靠工具。方法对SPSRQ进行翻译、回译、跨文化调试,形成青少年SPSRQ中文版(SPSRQ-A);2022年1月17日—9月30日采用随机抽样法和年级分层抽样法对1350名青少年施测,将总样本随机平均分成两组,采用一组数据进行项目分析和探索性因子分析,另一组数据进行验证性因子分析、效标效度和信度检验。结果SPSRQ-A中文版包含奖励敏感性(16个条目)和惩罚敏感性(21个条目)2个维度,累计方差贡献率为54.321%。验证性因子模型主要拟合指标符合测量学要求(χ^(2)/df=3.156,RMSEA=0.059,SRMR=0.062,CFI=0.906,NNFI=0.900);条目内容效度指数(I-CVI)均为0.800~1.000,平均量表内容效度指数(S-CVI/Ave)为0.970;SPSRQ-A中文版2个维度得分与2个效标量表得分显著相关(r=-0.453~0.604,P<0.001)。信度检验:总量表和敏感性、惩罚敏感性维度Cronbach′sα系数为0.883~0.953,折半信度为0.887。结论SPSRQ-A中文版信效度良好,可作为评价我国青少年强化敏感性的有效工具。

关键词：奖惩敏感性问卷中国青少年信度效度