表面闭合优先发生情况下入水动力学建模与分析

本文研究了三维细长弹体以固定速度垂直入水问题,研究范围被限制在表面闭合优先于深闭合发生情况下的空气腔形成阶段。我们建立了弹体发射实验装置,通过高速相机拍摄了入水过程的时序图像。我们还在开源流体力学平台OpenFOAM~?上开发了基于压力的可压缩多相求解器,用于开展入水流场特性数值模拟研究,采用数值计算得到的空泡形态与实验结果吻合良好。本文讨论了在不同佛汝德数工况下,弹体阻力系数、压力分布、空腔轮廓和流动特性随着无量纲时间的变化规律。分析结果表明,阻力系数在接触水面的瞬间发生突变达到峰值,随后快速下降并达到一个相对稳定的值,空腔入口处和弹体的肩部存在着明显的低压,随着气体侵入的减少和空气腔体积的增大,泡内的整体压力不断降低

AHPN衍生物的合成及其与RARγ的结合活性研究

目的本实验以6-{3’-(1-金刚烷基)-4’-羟基苯基}-2-萘甲酸(AHPN)母核为结构基础,设计、合成一系列AHPN衍生物,并对这些衍生物做初步的活性筛选,期望找到活性显著的衍生物。方法以对溴苯酚和1-金刚烷醇为原料经取代、缩合、氧化、还原等反应合成AHPN衍生物,经过1H-NMR、13C-NMR、HR-MS表征,并利用Biacore技术检测衍生物与蛋白质之间的结合能力。结果衍生物7c、6c、6e、6h显示出了显著优于先导化合物AHPN与视黄酸核受体γ(RARγ)的结合能力,亚磷酸二甲酯基与氮杂环的引入提高了该类化合物的活性。结论该类AHPN衍生物与RARγ结合能力显著,有进一步研究的价值。扬州市邗江区科技计划项目资助;;福建省基金项目资助(2014Y0044);;国家海洋局第三海洋研究所基本科研业务费专项资金资助项目(海三科2016044

癌症“种子土壤说”新论

\"种子土壤\"理论最初被应用于肿瘤转移相关学说,文章根据癌症的发生、发展和转移等规律,从另一个全新的角度来定义\"种子土壤说\",呈现直观又形象的癌症解读,并且将这种理论应用于指导癌症的诊断、预防和治疗,体现出在未来中医和西医的融合必将会是医学发展的大势所趋。厦门市重大科技计划项目(No.3502Z20100006);;厦门市科技计划高校创新项目(No.3502Z20153027)~

粉煤灰-矿粉-水泥三元胶凝材料对混凝土抗压强度的影响

为研究粉煤灰-矿粉-水泥三元胶凝材料对混凝土抗压强度的影响,测试混凝土标准养护3、7、14、28和56 d龄期的抗压强度,分析凝土抗压强度与胶凝材料各组分的关系。实验结果表明,混凝土抗压强度与粉煤灰-矿粉-水泥三元体系组分的掺量比例有密切关系。粉煤灰和矿粉双掺时,由于粒径不同会相互填充,从而产生超叠加效应,使掺加粉煤灰和矿粉的混凝土抗压强度得到明显改善。水泥、矿粉、水泥及粉煤灰的组合、粉煤灰和矿粉的组合对混凝土的抗压强度有增强作用,其中粉煤灰和矿粉的协同效应对混凝土抗压强度增强最为明显。随着龄期增加,粉煤灰和矿粉的协同效应对混凝土抗压强度的增强作用逐渐减弱,与28 d抗压强度相比,其对56 d抗压强度贡献降低了55.9%;粉煤灰及水泥-粉煤灰-矿粉的三元组合对混凝土抗压强度的影响逐渐降低,与28 d抗压强度相比,粉煤灰及水泥-粉煤灰-矿粉的三元组合对56 d抗压强度的降低效应分别减少了40.9%和67.3%。国家自然科学基金项目(51778551)福建省科技厅青年创新项目(2016J0514

石子级配对混凝土工作性的影响

基于研究石子级配对混凝土工作性的影响,对混料设计方法设计了10组三级配石子混凝土配合比,测试了不同石子级配的混凝土的坍落度和扩展度,并对测试结果进行优化。结果表明:石子级配对混凝土工作性有重要影响,良好的石子级配可有效改善混凝土的工作性。采用混料设计的方法设计的混凝土配合比,可在尽量少实验量的基础上快速有效得到满足工作性要求的石子比例

Analysis on the clinical experience of WANG Yan-hui in the treatment of tumor by syndrome differentiation based on Xiang thinking

王彦晖教授从事肿瘤中医治疗30余年,积累了丰富的临床诊疗经验。认为中医辨证论治思维的关键在于病机指导下的象症辨证。气滞、痰湿、瘀血等病理产物贯穿; 肿瘤病机的始终。病理产物必须除之而后快,而正气和脏腑的调理是祛邪的保障。病机的轻重缓急,应以象的变化为凭证。病机不变,象不变,临床上即应守方用药; 。王教授在临证中强调据象诊断、据象治疗、据象的变化反馈调整处方用药的中医诊疗思想颇具特色。Professor WANG Yan-hui has accumulated a wealth of clinical experience; in the treatment of tumor for more than 30 years. He thinks that the key; point of treatment based on syndrome differentiation is according to; Xiang thinking that under the guidance of pathogenesis. Qi stagnation,; phlegm-damp, static blood and other pathological products are always; complicated throughout the tumor pathogenesis. The pathological products; must be wiped out, while the regulation of vital qi and zang-fu viscera; is the insurance for eliminating pathogen. The order of priority of; pathogenesis should be according to the changes of Xiang. As the; pathogenesis and Xiang remains unchanged, the prescription of clinical; medication should be keeping the same. Professor WANG emphasizes that; diagnosis and treatment should be according to Xiang in the clinical.; The prescription adjustment by feeding back from the changes of Xiang is; a special characteristic of traditional Chinese medicine in diagnosis; and treatment.厦门市重大科技计划项目; 厦门市科技计划项

Electrochemical method detect the iron in the river based on AuNPs-nafion modified electrode combined with automatic sampling system

A new detection system was developed based on automatic sampling technology combined with AuNPs-Nafion modified electrode. Through the optimized condition of detection system depends on different parameters,such as the material of the modified electrodes with enrichment of time. Under the optimal conditions,the instrument detection limit for Fe(Ⅲ) was 4.5 nmol&middot;L~(-1),linear range of 25 nmol&middot;L~(-1)-1 mumol&middot;L~(-1). Finally,the total iron content in river water was tested and compared with ICP-AES,basically where test results were the same. This instrument had the advantages of convenience and low detection cost,and it had been wide application prospects in realtime detection.</p

作物花粉高温应答机制研究进展

随着全球气候变暖加剧,农作物面临更加严峻的高温威胁。高温胁迫影响作物生长发育各个阶段,其中花粉发育过程对高温胁迫最为敏感,因此花粉高温应答机制成为当前植物学研究热点。研究表明,花粉可以通过质膜上的钙离子通道、内质网中的未折叠蛋白反应、活性氧积累以及H2A.Z等机制感知高温胁迫,并通过调控热激蛋白表达、糖代谢、激素水平及活性氧清除能力适应高温胁迫。该文从高温对花粉发育的影响、花粉高温胁迫应答机制以及花粉高温胁迫研究的实验设计等方面进行综述,旨在为相关研究提供借鉴

On the airflow in a cavity during water entry

The airflow physics in the cavity during the entry of a symmetric wedge into water are investigated experimentally using flow visualization techniques and particle image velocimetry (PIV) measurements. The spatial and temporal evolutions of the airflow velocity in the cavity are presented. Smoke visualization indicates some small-scale flow phenomena like secondary vortexes, free shear layers, and Kelvin-Helmholtz (K-H) instabilities within the water entry cavity. The information of airflow velocity in the cavity is obtained via PIV measurements. The results show that ambient gas is entrained into the transient air bubble at the wake of the wedge and the air flow rate is nearly equal to the cavity volume change rate. Thus, it is feasible to use the airflow rate to predict the cavity volume change rate. When the wedge descends, the air-water interface has a significant effect on the wake vortex behaviors. The vortex areas shrink gradually and wake vortex circulation decreases over time. Thus, the air-water interface not only suppresses vortex growth but also leads to vortex dissipation