44 research outputs found

    一种压阻式压力传感器的温度补偿方法

    Get PDF
    针对压阻式压力传感器的温度补偿问题,提出一种将样条插值与最小二乘拟合相结合的补偿算法,并结合传感器标定实验数据进行仿真试验。结果表明该方法相比曲面拟合方法、BP神经网络和RBF神经网络,补偿最大相对误差和平均补偿时间分别为0.103%和0.135 4 s,不仅能够满足高精度测试要求,而且可减少标定工作量达到提升生产效率的目的。国家科技重大专项项目(2015ZX03003010

    Study on preparation and in vitro release behavior of hydroxycamptothecin-loaded PLA microspheres

    Get PDF
    目的:研究载羟基喜树碱的聚乳酸微球的制备方法并考察其体外释药性质。方法:以PlA为成膜材料,采用改良乳化-溶剂挥发法,制备载羟基喜树碱的聚乳酸微球并优化制备工艺;对载药微球进行表征;超声介导下进行载药微球的体外释药试验。结果:微球粒径在1~7μM,大小均一;羟基喜树碱浓度在10Mg.Ml-1下,载药微球包封率为62.2%,载药量为1.69%;药物体外释药符合HIguCHI方程。结论:采用乳化-溶剂挥发法,以PlA为成膜材料可制得具有较高包封率的羟基喜树碱微球,有望实现降低羟基喜树碱给药量、减少不良反应,提高靶向性的目标。Objective:To prepare hydroxycamptothecin(HCPT)-loaded PLA microspheres and study the release of HCPT in vitro.Methods:To optimize the preparation process,the HCPT-loaded PLA microspheres were prepared by using an improved solvent evaporation method;drug-loaded microspheres was characterized;in vitro drug release experiments were carried out under ultrasound.Results:The sizes of drug loaded PLA microspheres were homogeneous and between 1--7 μm;the concentration of HCPT was 10 mg·mL-1,the drug encapsulation efficiency was 62.2%,and the drug-loading amounts was 1.69%;the release in vitro complied with Higuchi equation.Conclusion:The improved solvent evaporation method with PLA as the film-forming material can increase the encapsulation efficiency of HCPT-loaded microspheres,thus the reduction of dosage and improvement of toxic effects of HCPT would be expected.Targeting effect may be improved.福建省卫生厅青年科研项目(2009-2-79

    Pharmacokinetics of Dual Conjugated Chitosan-mitomycin C Nanoparticles in Rats

    Get PDF
    目的研究双修饰壳聚糖载丝裂霉素C纳米粒在大鼠体内的药动学特征。方法 2组大鼠分别静脉注射4 Mg·kg·1丝裂霉素C纳米粒和丝裂霉素C注射剂后,采用高效液相色谱-串联质谱法(HPlC-MS)测定给药后不同时间点血浆中丝裂霉素C的浓度,计算主要药动学参数。结果丝裂霉素C的线性范围20~1 000μg·l·1,最低定量限为20μg·l·1,提取回收率均>95%,日内、日间精密度rSd均<15%。双修饰壳聚糖载丝裂霉素C纳米粒和丝裂霉素C注射剂T1/2分别为(2.64±0.11)H、(0.49±0.049)H;AuC0-∞分别为(2.01±0.11)Mg·H·1·l·1、(0.93±0.075)Mg·H·1·l·1;Vz分别为(1.52±0.18)l、(0.63±0.065)l;Cl分别为(6.95±0.70)Ml·MIn·1、(15.47±1.89)Ml·MIn·1,2者均有显著性差异。结论该方法灵敏、准确、专一,适用于丝裂霉素C的药动学研究。与丝裂霉素C注射剂相比,双修饰壳聚糖载丝裂霉素C纳米粒具有缓释和长循环的作用。OBJECTIVE To study the pharmacokinetics of dual conjugated chitosan-mitomycin C nanoparticles(CS-MMC-NPs) in rats.METHODS The two groups of rats were injected with CS-MMC-NPs and MMC injection at the dose of 4 mg·kg·1.The concentrations of MMC in plasma at different time were determined by HPLC-MS and the main pharmacokinetic parameters were calculated.RESULTS The calibration curves were linear over the range of 20·1 000 μg·L·1.The limit of quantitation was 20 μg·L·1.The within day and day to day relative standard deviation(RSD) was <15%.The main pharmacokinetic parameters of CS-MMC-NPs and MMC injection were as follows: t1/2 were(2.64±0.11)h and(0.49±0.049)h, AUC0- ∞ were(2.01±0.11)mg·h·1·L·1 and(0.93±0.075)mg·h·1·L·1, Vz were(1.52±0.18)L and(0.63±0.065)L, CL were(6.95±0.70)mL·min·1 and(15.47±1.89)mL·min·1.The differences of parameters were significant between two preparations.CONCLUSION The method is sensitive, accurate, specific for the pharmacokinetic study of CS-MMC-NPs.Compared with MMC injection, CS-MMC-NPs has a controlled releasing rate, a high level of blood concentrations and a long blood circulation time, which benefits the control of acute toxicity of MMC for the rats.厦门市科学技术计划项目资助项目(3502Z20114007

    胶原特性及其制备方法研究进展

    Get PDF
    本文阐述了胶原、明胶和胶原多肽三者的概念和不同点,介绍了胶原的结构以及Ⅰ型胶原和Ⅱ型胶原的差异,总结了胶原的七种制备方法,并对各种制备方法的优缺点进行分析,为水产动物资源制备胶原提供参考。福建省海洋生物增养殖与高值化利用重点实验室(361013);;福建省海洋生物资源开发利用协同创新中心(361013

    用FTIR测定羧酰化壳聚糖和氰乙基壳聚糖的取代度

    Get PDF
    从壳聚糖 (脱乙酰度分别为 84%和 70 % )合成不同取代度的羧酰化壳聚糖和氰乙基壳聚糖作为标样 ,标样的取代度 (DS)由NMR或元素分析确定 .研究以FTIR作为工具测定这两个系列衍生物的取代度的方法 .吸光度用基线法得到 ,对所有不同探针谱带 ,参比谱带和基线作图法的组合进行比较 ,并通过 (A探针/A参比) /DS的平均相对偏差评价每种组合的优劣 .结果表明 ,对羧酰化壳聚糖 ,最合适的A探针/A参比 是A174 0 /A152 7;对氰乙基壳聚糖 ,最合适的A探针/A参比 是A2 2 4 9/A1590 .前者不仅适用于不同取代度的同一种O 羧酰化壳聚糖 (如丙酰化壳聚糖 )而且适用于不同取代度且不同碳数的 4个O 脂肪酸羧酰基取代的壳聚糖样品 .这两种组合的工作曲线的斜率分别为 2 .1(对A174 0BL1/A152 7BL1) ,0 .5 9(对A2 2 4 9/A1590BL1)和 0 .6 6 (对A2 2 4 9/A1590BL2 ) .实验还表明 ,不同的基线作法对结果影响甚

    Preparation and Characterization of Folic Acid and PEG Conjugated Chitosan Nanoparticles

    Get PDF
    目的利用离子交联和化学交联相结合的方法制备壳聚糖纳米粒子(nPS),并对nPS分别进行了叶酸(fA)和聚乙二醇(PEg)的修饰。方法通过红外光谱进行结构验证;用扫描电镜和粒度分析仪对粒子的微观形态、粒径、电位等进行了表征;通过与HElA细胞摄取实验对其靶向作用进行验证。结果离子交联和化学交联相结合的方法制备壳聚糖纳米粒子粒径在200 nM左右并且粒径分布窄,修饰后的nPS(fA-nPS、PEg-nPS及fA+PEg-nPS)粒径不受功能基团修饰的影响。激光共聚焦试验证明fA-nPS及fA+PEg-nPS能显著提高细胞对粒子的摄取,而PEg-nPS则明显降低其对粒子的摄取。结论 fA+PEg-nPS有望成为一种新型的药物载体,用于抗癌药物对癌细胞的主动靶向。OBJECTIVE An ionic gelation combined with chemical crosslinking method was developed to prepare chitosan nanoparticles,followed by conjugation with folate(FA) and polyethylene glycol(PEG).METHODS The structures were verified by infrared spectroscopy.The morphology,diameter and Zeta electric potential of the nanoparticles were assayed by environmental scanning electron microscope and scattering particle analyzer.The specificity of the FA+PEG-NPs targeting cancer cells was demonstrated by human adenocarcinoma Hela cells.RESULTS The chitosan NPs presented a narrow size distribution with an average diameter about 200 nm regardless of the type of functional group.Laser confocal scanning imaging proved that both FA+PEG-NPs and FA-NPs could greatly enhance uptake by Hela cells.However,the PEG-NPs showed contrary results.CONCLUSION FA+PEG-NPs can be applied as a new vehicle to actively deliver anticancer drugs to tumor cells.厦门市科学技术计划资助项目(3502Z20114007

    C_(60)[RuHCl(CO)(PPh_3)]_3配合物的合成和表征

    Get PDF
    国家自然科学基金;教育部博士点基

    Simulation Study on Front Impact Safety of Medium Coach

    Get PDF
    建立半承载式中型客车的正面碰撞有限元模型,采用lS-dynA软件进行仿真分析。结果表明,该车驾驶室变形较大、完整性较差,需对客车前部吸能结构进行优化设计。The finite element model of front impact of medium coach is built,which body is semi-integral type.Using LS-DYNA software,the front impact safety is simulated.The results indicate that the drive cab deformation is bigger and its integrality is worse,so it is necessary to optimize the front absorbing structure components to the coach drive cab.交通部西部交通科技项目(2009318000043);福建省教育厅科技项目(JA11239);厦门理工学院科技项目(JKY10023R);福建省自然科学基本项目(2012J05103

    福建鲍产业发展形势分析

    Get PDF
    鲍,素有\"软黄金\"的美誉。自上世纪90年代开始,福建引入皱纹盘鲍与日本盘鲍的杂交鲍并逐渐扩大养殖规模。笔者归纳了福建省鲍的养殖分布及生产情况,结合鲍的消费结构及产业支撑现状发现鲍产业发展过程中的育苗场规划,养殖管理,种质退化,安全用药等方面存在问题,对此提出推进科学养殖,增强环保意识;加强管理制度建设,实现质量监管;加强种质管理,选育新品种;加强技术体系建设;提升产业融合度等建议

    一种新型核级FeCrAl合金的离子辐照行为

    Get PDF
    采用400 keV的Fe+离子在400℃下对一种新型核级Fe13Cr4Al合金进行了辐照,利用透射电镜(TEM)和纳米显微硬度仪分析及测试了其辐照前后的微观结构和硬度值。结果表明:Fe+离子辐照在合金基体中形成了大量位错环而未形成明显尺寸的空位团。随辐照剂量的增加,位错环尺寸不断增大,位错环体密度先增加,后趋于饱和,数值稳定在3.1×1022 /m3。辐照未使合金基体非晶化,但导致Laves析出相发生非晶化转变。随辐照剂量的增加,析出相中Nb、Mo、Ta和Cr 4种元素的含量呈减少趋势,而Si的含量却逐渐增加。在60~100 nm深度范围发生明显辐照硬化现象,临界深度值hc=100 nm。辐照硬化值与辐照剂量呈幂函数关系:ΔHIrr=0.4288(d)0.2311;而与微观组织参量(ND)0.5呈正相关:ΔHIrr=55.36(ND)0.5。国家自然科学基金(U1867201,U1832112);;\n厦门大学能源学院发展基金(2018NYFZ01
    corecore