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61.
62.
矩形非球面圆弧半径误差分离及补偿技术   总被引:1,自引:0,他引:1       下载免费PDF全文
研究了砂轮圆弧半径误差对大口径矩形轴对称非球面加工的影响。采用直线光栅式平行磨削的加工方式,建立了砂轮圆弧半径的误差分离的数学模型,分析影响面形精度的因素,根据加工及测量方式将砂轮圆弧半径误差分离出来,利用分离的砂轮圆弧半径误差更新砂轮圆弧半径,同时采用分离后的误差数据进行补偿加工。实验结果表明:对比不分离的补偿加工结果,粗磨和精磨条件下的分离误差补偿加工后的面形误差分别减小了14%和35%,该误差模型能够有效地分离出砂轮圆弧半径误差,分离误差效果明显,提高了加工的精度。  相似文献   
63.
A specific and accurate high-performance liquid chromatographic method for analysis of cinnamic acid (CA) and paeonol (PN) in rat plasma has been developed and validated. Plasma samples were pretreated by protein precipitation with methanol, and the supernatant was injected for reversed-phase separation on a C18 column with acetonitrile–0.1% phosphoric acid 24:76 (v/v) as mobile phase at a flow-rate of 1.0 mL min?1. Phenylbutyric acid was used as the internal standard. Good linear relationships were obtained between response and concentration in the range 0.130–52.0 μg mL?1 (r = 0.9980) and 0.1785–71.4 μg mL?1 (r = 0.9950) for CA and PN, respectively. Intra-day and inter-day assay precision (RSD, n = 6) at three concentrations was not above 15.1% for either CA and PN, and accuracy was from 94.3 to 104.7% and from 103.3 to 113.1% for CA and PN, respectively. Mean recovery of CA and PN from plasma samples was 87.5 and 86.8%, respectively, and recovery of the internal standard at a concentration of 1.00 mg mL?1 was 88.5%. Results from a stability study suggested CA and PN were stable under the experimental conditions used. Finally, the validated method was successfully applied to a pharmacokinetic study of CA and PN in rats after intragastric administration of Guizhi–Fuling capsule. The results obtained would be very useful for evaluation of the clinical efficacy of GFC.  相似文献   
64.
2-Methoxyestradiol is currently in phase II clinical trials as a chemotherapeutic agent. An LC method with fluorescence detection was developed for determination of methoxyestradiol in rat lung. Sample was extracted with ethyl acetate and separated on a C18 column (150 mm × 4.6 mm, 5 μm) with a mobile phase consisting of potassium dihydrogen phosphate-acetonitrile-triethylamine (55:45:0.3, v/v/v, pH 3.0). The excitation and emission wavelength were set at 285 and 325 nm, respectively. Standard curves were linear over the concentration range of 0.25–64 μg g?1. The method was found to be precise, accurate and specific and can be applied to tissue pharmacokinetics of methoxyestradiol in rats.  相似文献   
65.
刘菁华  孙振中  黄雪玲  郭霞  孙建华 《色谱》2015,33(4):434-440
建立了养殖水体及沉积物中11种磺胺化合物的高效液相色谱-柱后衍生分析方法。养殖水体过滤后采用HLB固相萃取柱进行净化、富集;沉积物采用甲醇/EDTA-Mcllvaine缓冲液(1:1, v/v)提取,HLB固相萃取柱净化富集。经高效液相色谱分离,用荧光胺衍生试剂进行柱后衍生,荧光检测器检测。对柱后衍生系统参数进行了优化,确定了荧光胺溶液的浓度、流速和反应温度分别为0.2 g/L、0.15 mL/min和50 ℃,磺胺化合物在0.01~1.0 mg/L范围内线性显著,其相关系数r2值大于0.99995。11种磺胺类药物在养殖水体和沉积物中的加标回收率分别为79.3%~100.7%和74.6%~95.3%,相对标准偏差为2.2%~11.0%和2.6%~10.3%,检出限(LOD, S/N=3)为0.9~5.5 ng/L和0.3~1.3 μg/kg,定量限(LOQ, S/N=10)为3.0~18.1 ng/L和1.0~4.4 μg/kg。该法可应用于养殖环境中磺胺类药物的定性定量检测,具有较好的实用性。  相似文献   
66.
用3-(甲基丙烯酰氧)丙基三甲氧基硅烷(MPS)、 氨丙基三乙氧硅烷(APTES)和正硅酸乙酯(TEOS)溶胀聚苯乙烯中空微球的壳层, 在壳层表面通过溶胶-凝胶过程, 使亲油和亲水基团通过自组装作用分别朝向聚苯乙烯基体和水相, 形成Janus结构. 用良溶剂N,N-二甲基甲酰胺(DMF)溶解除去聚苯乙烯, 得到二氧化硅基复合Janus纳米材料. 改变反应体系pH值和单体用量等可以调控Janus纳米材料微结构, 得到Janus中空球和纳米片.  相似文献   
67.
利用射频磁控溅射在石英衬底上生长出铟磷共掺氧化锌薄膜(ZnO ∶ In,P),所用靶材为掺杂五氧化二磷(P2O5)和氧化铟(In2O3)的氧化锌(ZnO)陶瓷靶,掺杂质量分数分别为1.5%和0.3%,溅射气体为Ar和O2的混合气体。原生ZnO薄膜是绝缘的, 600 ℃退火5 min后导电类型为n型,而800 ℃退火5 min后为p型。p型ZnO薄膜的电阻率、载流子浓度和霍尔迁移率分别为12.4 Ω·cm, 1.6×1017 cm-3 和3.29 cm2·V-1·s-1。X射线衍射测量结果表明所有样品都只有(002)衍射峰,并与相同条件下生长的未掺杂ZnO相比向大角度方向偏移,意味着In和P都占据Zn位。XPS测试结果表明在共掺ZnO薄膜中P不是取代O而是取代Zn。因此,铟磷共掺ZnO薄膜中,In和P都取代Zn,并且PZn与2个锌空位(VZn)形成PZn-2VZn复合受主,薄膜表现为p型。  相似文献   
68.
A novel one-color Xe+-N laser induced collisional charge transfer system is proposed, and preparation of the initial state of the system, i.e., Xe+ is experimentally implemented through resonance enhanced multi-photon ionization (REMPI) by ~440 nm dye laser. The REMPI of Xe is experimentally investigated through time-of-flight (TOF) mass spectrometry and the intensity dependence of Xe+ is obtained, aiming at the preparation of Xe+. The resonant ionization spectra of Xe at ~440 nm under several different conditions are measured, showing the impacts of mode purification and source pressure on the resonant ionization spectrum. The results indicate the feasibility of preparing the initial state of the Xe+-N system by ~440 nm multi-photon resonant ionization, which prepares for a further experiment of laser-induced collisional charge transfer.  相似文献   
69.
荧光光度法测定大气、水和土壤中痕量汞   总被引:1,自引:0,他引:1  
本文研究了汞离子与硫化荧光素汞反应定量地释放出荧光素汞的条件,提出了一种间接测定痕量汞的荧光光度法。应用于大气、水和土壤中痕量汞的测定,方法简便、快速。  相似文献   
70.
Sub‐micron waterborne dispersions of crosslinked bisphenol A epoxy resin were prepared by a phase‐inversion emulsification process in the presence of N,N‐dimethylbenzylamine as the curing agent. Differential scanning calorimetry was used to monitor the extent of crosslinking by post‐polymerization. The time and temperature of post‐polymerization influence the extent of crosslinking. Particle size could be controlled in the range 100–300 nm with a narrow size distribution by varying the content of curing agent and polymeric emulsifier, as investigated by means of scanning electron microscopy. A tentative physical model of the phase‐inversion emulsification process in the presence of curing agent is proposed.  相似文献   
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