Large-eddy simulation of flows past a flapping airfoil using immersed boundary method

The numerical simulation of flows past flapping foils at moderate Reynolds numbers presents two challenges to computational fluid dynamics: turbulent flows and moving boundaries. The direct forcing immersed boundary (IB) method has been developed to simulate laminar flows. However, its performance in simulating turbulent flows and transitional flows with moving boundaries has not been fully evaluated. In the present work, we use the IB method to simulate fully developed turbulent channel flows and transitional flows past a stationary/plunging SD7003 airfoil. To suppress the non-physical force oscillations in the plunging case, we use the smoothed discrete delta function for interpolation in the IB method. The results of the present work demonstrate that the IB method can be used to simulate turbulent flows and transitional flows with moving boundaries

How flexibility affects the wake symmetry properties of a self-propelled plunging foil

The wake symmetry properties of a flapping-foil system are closely associated with its propulsive performance. In the present work, the effect of the foil flexibility on the wake symmetry properties of a self-propelled plunging foil is studied numerically. We compare the wakes of a flexible foil and a rigid foil at a low flapping Reynolds number of 200. The two foils are of the same dimensions, flapping frequency, leading-edge amplitude and cruising velocity but different bending rigidities. The results indicate that flexibility can either inhibit or trigger the symmetry breaking of the wake. We find that there exists a threshold value of vortex circulation above which symmetry breaking occurs. The modification of vortex circulation is found to be the pivotal factor in the influence of the foil flexibility on the wake symmetry properties. An increase in flexibility can result in a reduction in the vorticity production at the leading edge because ofthe decrease in the effective angle of attack, but it also enhances vorticity production at the trailing edge because of the increase in the trailing-edge flapping velocity. The competition between these two opposing effects eventually determines the strength of vortex circulation, which, in turn, governs the wake symmetry properties. Further investigation indicates that the former effect is related to the streamlined shape of the deformed foil while the latter effect is associated with structural resonance. The results of this work provide new insights into the functional role of passive flexibility inflapping-based biolocomotion

Determination of nitrofuran residues in feed and water samples by monolith-based stir bar sorptive extraction and high performance liquid chromatography

利用自制的以聚(乙烯基咪唑-二乙烯基苯)(VIdb)整体材料为涂层的固相萃取搅拌棒(VIdb-SbSE)萃取3种硝基呋喃类药物,然后与高效液相色谱-二极管阵列检测器联用建立了测定饲料和水样品中硝基呋喃类药物残留的方法。详细考察了萃取过程中萃取和解吸时间、样品基质的PH值以及离子强度等实验条件对萃取效率的影响。在最佳条件下,呋喃唑酮的线性范围为0.5~200μg/l,呋喃妥因和呋喃西林的线性范围为0.25~200μg/l,3种目标物的检出限(lO d)(S/n=3)在0.068~0.11μg/l之间,所建方法具有理想的日内和日间重现性(r Sd值均小于6%)。在对饲料和实际水样的测定中,不同加标浓度呋喃唑酮、呋喃妥因和呋喃西林的回收率在80.6%~108%之间。研究表明,所建立的方法具有简便、灵敏、环境友好等特点。A simple,efficient and sensitive method for the simultaneous determination of nitrofurantoin( NFT),furazolidone( FZD) and nitrofurazone( NFZ) in feed and water samples was developed by stir bar sorptive extraction( SBSE) coupled to high performance liquid chromatography w ith diode array detection.T he SBSE based on poly( vinylimidazole-divinylbenzene)( VIDB) monolithic material as coating w as used to concentrate the three target analytes.T o obtain the optimum extraction performance, several VIDB-SBSE parameters w ere investigated and studied,including pH value,ionic strength of sample matrix,extraction and desorption time.U nder the optimized experimental conditions,the linear ranges w ere 0.5- 200 μg / L for FZ D,0.25- 200 μg / L for N FT and N FZ.T he limits of detection( S / N = 3) w ere in the range of 0.068- 0.11 μg / L for the three analytes.T he precision of the proposed method w as evaluated in terms of intra- and inter-day repeatability calculated as R SD,and it w as found that the R SDs w ere all below 6%.T he developed method w as successfully applied to the determination of nitrofuran residues in animal feed and w ater samples.T he satisfactory recoveries of the spiked target compounds w ere in the range of 80.6%- 108%.国家自然科学基金项目(21377105;21077085); 福建省新世纪优秀人才项

不同形貌普鲁士蓝纳米粒子的合成及光热性能

制备了立方体、直角立方体、球形、棒状、中空状、核壳状、梭形、多面体等8种不同形貌的普鲁士蓝纳米粒子,利用扫描电子显微镜、透射电子显微镜、紫外-可见分光光度计等对纳米粒子进行了表征,考察了普鲁士蓝纳米粒子光热性能的影响因素.结果表明,普鲁士蓝纳米粒子的形貌与光热性能之间联系密切,粒子形貌不同,光热性能不同;当外部实验条件一定时,纳米粒子的形貌、大小、吸收横截面积、尖锐化程度及密实程度等对其光热性能有很大的影响;当纳米粒子形貌一定时,外部因素如激光器的选择、激光功率密度及纳米粒子的浓度等直接影响普鲁士蓝纳米粒子的光热性能;在相同浓度下,激光功率密度越大,纳米粒子的升温效果越明显,光热性能越好;而激光功率密度不变时,纳米粒子浓度越大,其光热转换效率越高.国家自然科学基金(批准号:31271071,31371012,U1505228)资助~

InFluence of Laser Irradiation on Serum Albumen of Castor Silkworm

我们采用不同波长的激光照射蓖麻蚕蚕卵，使它产生半致死效应，经孵化后的幼虫在五龄期取血分析它的血清蛋白谱，证实了激光照射对蓖麻蚕的遗传性状具有诱变作用，其机理涉及到激光照射与基因表达及调控的关系。Eggs of castor silkworm are irradiated with diFFerent wavelengths of laser and they are made to produce the semilethal eFFect.AFter incubation, taking some blood From larva at the age of Five, the spectra of its serum albumen is analysed.It has been conFirmed that laser irradiation has a mutagenesis on heredity of castor silkworm.the mechanism involved with the relation of laser irradiation with gene expression, as adjuustion and control.福建省自然科学基

透皮促进剂对白花前胡甲素体外经皮渗透的影响

目的:考察透皮促进剂对白花前胡甲素(dl-praeruptorin A,Pd-Ia)体外经皮渗透的影响。方法:采用改进的Franz扩散池,以大鼠离体皮肤为渗透屏障,用高效液相色谱法对Pd-Ia进行含量测定,考察月桂氮酮(Azone)及1%Azone与不同浓度丙二醇(PG)混合物对Pd-Ia透皮吸收的影响。结果:使用Azone对Pd-Ia有促透作用,1%Azone效果较好,平均渗透速率达到4.064μg.cm-2.h-1;1%Azone与15%PG合用促透效果最好,平均渗透速率达到4.889μg.cm-2.h-1,且与单用1%Azone有显著性差异(P<0.05)。结论:1%Azone与15%PG合用时,含0.5%Pd-Ia溶液体外渗透具有最大促透效果,体现出协同作用

Preparation of sorbent based on porous monolith incorporated with graphene oxide nanosheets for stir cake sorptive extraction of strongly polar aromatic amines

National Natural Science Foundation of China [21377105, 21077085]; Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry; New Century Excellent Talents in Fujian Province UniversityIn this study, poly(ethylene glycol dimethacrylate/graphene oxide) (EDMA/GO) monolith was prepared by one-step in situ polymerization. The porous monolith was used for the first time as the sorbent of stir cake sorptive extraction (SCSE) for the preconcentration of strongly polar aromatic amines (AAs) from water samples. The effect of the content of EDMA and GO in the monolith on the extraction efficiencies was investigated in detail. The sorbent was characterized by elemental analysis, transmission electron microscopy, scanning electron microscopy and infrared spectroscopy. Analysis of polar AAs in environmental water samples by a combination of poly(EDMA/GO)-SCSE and HPLC with diode-array detection was selected as a paradigm for the practical application of the new sorbent. Under the optimal conditions, the limits of detection (S/N = 3.0) of the developed method for AAs ranged from 0.04 to 0.19 mu g L-1. Good reproducibility of the method was obtained as intra-and inter-day precisions, the relative standard deviations (RSDs) were less than 4.0%. Finally, the proposed method was successfully applied to the determination of trace AAs in environmental water samples. The recoveries of AAs spiked in different matrices ranged from 74.2% to 105%, and RSDs of repeatability ranged from 1.6% to 9.6%

Development of chemiluminescent microparticle immunoassay for quantitative determination of dehydroepiandrosterone sulfate

目的研制硫酸脱氢表雄酮化学发光免疫定量检测试剂。方法利用硫酸脱氢表雄酮人工完全抗原免疫小鼠,通过杂交瘤技术制备特异性抗硫酸脱氢表雄酮单克隆抗体,采用竞争抑制法建立硫酸脱氢表雄酮化学发光免疫定量检测试剂。结果筛选获得了27株稳定分泌抗硫酸脱氢表雄酮的单克隆抗体细胞株,建立了化学发光微粒子免疫法定量测定硫酸脱氢表雄酮的试剂盒雏形,与雅培公司的硫酸脱氢表雄酮定量检测试剂在检测临床标本上的相关系数r达0.99以上。结论本研究为国产化硫酸脱氢表雄酮化学发光微粒子免疫法定量测定试剂盒的研发奠定了基础。Objective To develop chemiluminescent microparticle immunoassay for quantitative determination of dehydroepiandrosterone sulfate.Methods Mice were immunized by dehydroepiandrosterone sulfate artificial complete antigen.Monoclonal antibodies against dehydroepiandrosterone sulfate were prepared by hybridoma technique.Chemiluminescent microparticle immunoassay for quantitative determination of dehydroepiandrosterone sulfate was developed based on competitive binding method.Results 27 monoclonal antibodies were obtained.Chemiluminescent microparticle immunoassay for quantitative determination of dehydroepiandrosterone sulfate prototype kit was established.The coefficient r of testing specimens with reagent from Abbott company was over 0.99.Conclusion Development of domestic chemiluminescent microparticle immunoassay for quantitative determination of dehydroepiandrosterone sulfate reagent was laid foundation by this study.国家高技术研究发展计划(863计划)(2011AA02A101

聚乙二醇修饰脂质体阿霉素联合顺铂单次给药治疗晚期骨肉瘤的剂量递增试验

目的为了探索聚乙二醇修饰脂质体阿霉素(PLD)联合顺铂在骨肉瘤化疗中PLD的最大耐受剂量(MTD)。方法纳入经病理确诊的转移性或不可切除的骨肉瘤患者14例，接受1个周期的PLD联合顺铂方案化疗。PLD分为3个剂量水平(40、50和60 mg/m2，第1天)，每个剂量组计划入组3例患者，按3+3方法进行剂量递增；顺铂(100 mg/m2，分成4 d使用)的剂量保持不变；每21 d一个疗程。受试者在化疗结束后48 h接受粒细胞刺激因子预防性升白细胞治疗。按照NCI CTCAE v4.0统计不良反应。结果纳入研究的患者中有男性9例，女性5例，中位年龄为20 (14～43)岁。在PLD剂量递增至60 mg/m2剂量组，入组的2例患者均出现3级口腔黏膜炎合并4级中性粒细胞减少性发热，达到剂量限制性毒性，因此下调一个剂量等级。在50 mg/m2剂量组，一共入组9例患者，仅1例患者出现剂量限制性毒性，表现为4级血小板减少持续大于3 d。在入组的所有患者中，观察到的3～4级不良反应为中性粒细胞下降(12例，12/14)、血小板减少（7例，7/14）、贫血（4例，4/14）及口腔黏膜炎(2例，2/14)。所有不良反应经对症、支持治疗后均可缓解，无治疗相关死亡。结论在PLD联合顺铂治疗晚期骨肉瘤的化疗方案中，PLD的最大耐受剂量为50 mg/m2，主要剂量限制性毒性为口腔黏膜炎及中性粒细胞减少性发热，不良反应经对症治疗后可缓解

SBA-15 supported vanadium oxide catalyst for selective oxidation of methane

The VOx/SBA-15 has been found to be a better catalyst for the selective oxidation of methane to formaldehyde than SBA-15-supported Mo and W oxides. The influences of catalyst support and vanadium source on catalytic performances have been studied. The results show that SBA-15 is a better support than MCM-41 and Cab-O-Sil, and the catalyst with NH4VO3 as the precursor exhibits higher performances. The addition of phosphorus has been found to enhance slightly the selectivity to HCHO. Characterizations by XRD, N-2 physical adsorption, Raman spectroscopy and H-2-TPR suggest that the supported VOx species with loading amounts lower than 3 wt% be highly dispersed (probably as monomer) and contribute to the selective oxidation of methane to formaldehyde