动态冲击下泡沫能量吸收对头盔防护性能的影响

为摩托车头盔的安全性设计,需要研究在冲击载荷下内衬泡沫的能量吸收能力对摩托车头盔防护性能的影响。该文建立了有限元数值分析头盔模型,依据欧洲经济委员会(ECE)的法规ECE R22.05的动态测试方法,验证该模型的有效性。改变头盔不同测试点下的泡沫密度,进行了12个跌落的仿真试验。结果表明:在头盔的前部、冠部和后部测试点区泡沫密度由40 kg/m3增加到80 kg/m~3时,泡沫的能量吸收能力逐渐增大,头部冲击能量衰减得更快,导致3个测试点头部颅骨骨折的风险从25%、55%、39%分别增大至53%、96%、96%。头盔右侧部测试点区域下的泡沫密度与颅骨骨折风险没有显著的关系。因而,头盔的安全性设计应同时兼顾内衬泡沫密度与尺寸。国家自然科学基金(51775466);;国家外专局高端团队项目(GDT20173600037);;福建省科技创新平台项目(2016H2003

硝基芳烃类污染物对水生态系统的毒理研究述评

硝基芳烃主要通过废水、粉尘、蒸气等形式污染环境,影响人体健康.从其对水生生物(包括生产者、消费者和分解者)的形态结构、生理生化、分子机制和对水生态系统的影响等方面综述了它们的生态毒害和致毒机理

非离子态氨对转“全鱼”生长激素基因鲤鱼的急性毒性和慢性毒性

在自然水体和人工水体中氨氮对鱼类是有毒的.利用静水更新式生物测试研究了非离子态氨对转基因鲤鱼和对照鱼的96h急性毒性实验和21d慢性毒性实验.通过96h非离子态氨急性毒性实验发现,转基因鲤鱼的非离子态氨氮24,48,72和96h半数致死浓度(LC50)(2.64,2.44,2.28和2.16mg/L)分别比对照鲤鱼相应的24,48,72和96h半数致死浓度(LC50)(2.70,2.64,2.52和2.33mg/L)略低,没有显著性差异;但在不同非离子态氨氮(3.86,3.29和2.09mg/L)胁迫下

Studies on chemical constituents in ethanolic extract from Acanthus ilicifolius as a pharmaceutic mangrove

目的探讨老鼠簕的化学成分。方法将老鼠簕全株粉碎后,用95%乙醇浸提3次,合并浓缩,浸膏的石油醚部位经反复硅胶柱层析分离,结合波谱学数据鉴定化合物结构。结果从石油醚部位分离得到8个化合物,分别为β-谷甾醇(Ⅰ)、豆甾醇(Ⅱ)、正十六烷酸(Ⅲ)、正二十八烷酸(Ⅳ)、4,22-二烯-3-酮豆甾烷(stig-masta-4,22-dien-3-one)(Ⅴ)、4-烯-3-酮豆甾烷(stigmast-4-en-3-one)(Ⅵ)、5,22-二烯-7-酮-3β-羟基豆甾烷(3β-hydroxystigmasta-5,22-dien-7-one)(Ⅶ)、2-唑啉酮(2-benzoxazolinone)(Ⅷ)。结论其中Ⅴ,Ⅵ,Ⅶ为首次从该植物中分离得到。Objective To study the chemical constituents of Acanthus ilicifolius.Methods The air-dried and powdered plant material was extracted with 95% ethanol.Silica gel and Sephadex LH-20 column chromotography were used in the isolation from the ethanol extracts of the whole plant,the compounds were determined on the basis of various modern spectroscopic analyses and physical constants.Results Eight compounds were isolated from the petroleum ether soluble portion,identified as β-sitosterol(Ⅰ),stigmasterol(Ⅱ),n-hexadecane acid(Ⅲ),n-octacosanic acid(Ⅳ),stigmasta-4,22-dien-3-one(Ⅴ),stigmasta-4-en-3-one(Ⅵ),3β-hydroxystigmasta-5,22-dien-7-one(Ⅶ) and 2-benzoxazolinone(Ⅷ).Conclusion CompoundⅤ,Ⅵ,Ⅶ were obtained from the genus for the first time.国家自然科学基金(30671646);; 福建省科技计划资助项目(2003Y036

Development of a quantitative ELISA detection method for Coxsackievirus A group 16 strain(CA16) antigen

目的:建立柯萨奇病毒A组16型(CA16)抗原的双抗体夹心ElISA定量检测方法,用于CA16灭活疫苗的研发和生产过程的抗原定量检测。方法:以CA16中和单抗T26H12为包被抗体、nA14b9为标酶抗体,构建定量检测CA16抗原的双抗体夹心ElISA方法,并对方法的特异性、灵敏度、精密度、准确性、线性和稳定性进行分析。结果:建立了双抗体夹心定量检测CA16抗原的ElISA方法。方法的线性相关系数r2=0.998,线性范围为8~128 ng/Ml,定量限度为8 ng/Ml;变异系数CV80%;与CA16以外的其他样本没有交叉反应。结论:构建的CA16抗原ElISA定量检测方法的各项性能符合定量检测需要,可用于CA16疫苗的研发和生产过程的抗原活性的定量检测。Objective:To develop an a quantitative enzyme linked immunosorbent assay(Q-ELISA) to determine the concentration of Coxsackievirus A Group 16 Strain(CA16) antigen.This method was used to determine CA16 antigen content at each stage of CA16 vaccine developing and manufacturing process.Methods:A double antibody sandwich Q-ELISA was developed to determine concentration of CA16 antigen,which was based on the high-affinity neutralizing monoclonal antibodies T26H12 as capture antibodies,and NA14B9 as HRP-labeled antibody.The performance of reagent were evaluated.Results:The Q-ELISA for CA16 antigen content was successfully developed.The reagent had good performance.The quantitation scope was 8-128 ng/ml,the coefficient correlation was 0.998,the limit of detection was 8 ng/ml,the recovery was between 87% and 113.8%.The stability was up to 80% after reagent was heated for 6 days at 37℃.The variation coefficient was lower than 15%,and thereagent was no reaction with other sample except CA16 antigen.Conclusion:The Q-ELISA for CA16 antigen was developed with good specificity,accuracy,precision and stability.The method can be used to determine CA16 antigen content during development and production of CA16 vaccine

Robust Flight Control System Design for BTT Missile

飞行控制系统设计是倾斜转弯（ B T T ）控制型导弹的-项关键技术.B T T 导弹转弯和 机动时需绕其速度矢量快速滚转,因而会导致较强的俯仰与偏航通道耦合，给飞行控制系统设计 带来困难.本文对BTT 导弹飞行控制系统进行设计,内回路采用蕴匝砸控制方法以抑制系统不确 定性;外回路采用混合灵敏度H∞鲁棒控制方法以抑制外部干扰和消除模型不确定带来的影响. 仿真验证表明,所设计的BTT 导弹飞行控制系统满足控制性能要求,目标拦截性能优于基于经典 控制方法设计的BTT 导弹飞行控制系统性能.Flight control system design is a key technique for bank-to-turn （BTT） missile. Because BTT missile needs to spin around its velocity vector rapidly when it makes a turn or maneuver,this will result in stronger coupling between pitch and yaw channels and bring difficulty for the flight control system design. In this paper,a flight control system design is performed for BTT missile,in which,LQR control method is employed in the inner loop to suppress system uncertainty,and the mixed sensitivity 匀肄 control method is used in the outer loop to suppress outside disturbance and eliminate the effect caused by model uncertainty. Simulation results demonstrate that the designed BTT flight control system satisfies the control performance requirements, a n d has better target interception performances c o m p a r e d to the flight control system designed with classic control method.国家自然科学基金项目（61673327）曰航空科学基金项目（20140168001;20160168001

不同管理体制下政府投入对基层农技推广人员从事公益性技术推广工作的影响

农业科技创新是发展现代农业的科技支撑,作为其中一个重要环节的农业技术推广体系却因为目前存在的种种问题,改革迫在眉睫。但人们在改革措施的先后顺序上存在分歧,阻碍了这一进程。本文的主要研究目的是在大量的实际调查基础上,通过计量经济模型的实证分析,揭示在不同的管理体制下,基层农技推广人员从事公益性技术推广职能与政府投入的关系。我们的研究表明,目前我国基层农技推广体系难以发挥其公益性技术推广职能;政府投入虽然近年来有明显提高,但总量仍然严重不足;不同体制下政府投入的效果显著不同,促进基层农技推广体系的管理体制改革有助于提高投入的效果。在此基础上,我们提出了相应的政策建议