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Search Results: 1 - 10 of 118198 matches for " 孙宝良 "
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高浓度青霉素含量的旋光法测定及影响因素分析
Optical Rotation Method for the Determination of the Content of the High Concentration of Penicillin and Influence Factors Analysis
 [PDF]

李百芳,
Journal of Advances in Physical Chemistry (JAPC) , 2012, DOI: 10.12677/JAPC.2012.13007
Abstract:
青霉素钠是一种临床常用的抗生素,其干燥粉末性状稳定,但配置成水溶液后性状极不稳定,易被酸、碱、醇、氧化剂、金属离子分解破坏,某种情况下其旋光度也将发生相应的变化,因此临床上为保证药效要求青霉素溶液需现用现配,必要时应及时检测浓度的变化[1]。有关青霉素含量的测定方法有很多,其中包括碘量法、固定pH滴定法、分光光度法、HPLC法、旋光法等。由于青霉素溶液的旋光度和浓度在一定范围内具有线性关系的特点,以往曾有文献报道,通常仅对1.0 mg/ml~10.0 mg/ml的低浓度青霉素溶液适用旋光法测定。本文依据旋光法对较高浓度青霉素的含量进行测定,同时对实验的有关影响因素进行研究和分析。实验结果表明,青霉素溶液在10.0 mg/ml~30.0 mg/ml的高浓度范围内也呈良好的线性关系,其线性方程为y = 0. 2903x + 0.1712,相关系数r = 0.9993。对比药典中采用的碘量分析法,旋光法具有操作简便快速、结果准确可靠、节省实验材料等优点,并且在一定程度上可以消除其他因素的影响,具有较高的应用价值,非常适合于一般医药院所的快速检测。
Penicillin sodium is a commonly used clinical antibiotic. It is noted that the dry powder is stable, but in water solution it is very unstable. It is easily decomposed and destructed by acid, alkali, alcohol, oxidative agent, metal ion. Thus, to ensure the efficiency of penicillin solution, it is clinically required to prepare it just before use. In some cases, it is necessary to timely detect the concentration changing. There are many methods to check the content of the penicillin solution, such as, the iodometric method, pH fixed titration, spectrophotometric method, HPLC method, and optical method. In the literature a linear relationship between optical rotation and concentration at lower concentration of 1.0 mg/ml - 10.0mg/ml has previously been reported. In this paper, we investigated content determination of penicillin at higher concentrations based on polarimetric method, and studied the role of the influencing factors. The experimental results showed that penicillin solution at 10.0 mg/ml - 30.0 mg/ml high concentration also show a good linear relationship, the linear equation is y = 0.2903x + 0.1712, the correlation coefficient
差示旋光法对VC含量的测定及分析
Differential Polarimetry Measurement and Analysis of the Content of VC
 [PDF]

, 孙文涛
Journal of Advances in Physical Chemistry (JAPC) , 2012, DOI: 10.12677/JAPC.2012.12003
Abstract:
维生素C的含量测定主要有碘量法、分光光度法、旋光法、高效液相色谱法、薄层扫描法等多种测量方法,其中碘量法测量过程较为繁琐,且不易排除辅料对维生素C复方制剂的干扰[1];而分光光度法、高效液相色谱法、薄层扫描法等对测量仪器要求较高,加大了检测成本[1]。本文应用物理学方法,借助于线性回归理论,利用维生素C在不同pH的溶液中其旋光度有显著差异,并且其差示旋光度和浓度在一定范围内呈线性关系的特点,通过差示旋光法对VC注射液的含量进行测定,同时对实验的有关影响因素进行研究分析。结果表明VC注射液在2.50 mg/ml~12.5 mg/ml范围内浓度与差示旋光度的线性关系良好,得到的相关方程为y = 0.1835x + 0.0113,相关系数r = 0.996。对比其他测量方法,该方法简单可靠,结果合理,从而达到快速、简便、准确的测定VC含量的目的,尤其适用于中小医院相关科室对药物的快速检测。
Determination of vitamin C content of the main iodometry, spectrophotometry, polarimetry, HPLC, TLC scanning method and other methods of measurement, iodometric method for the measurement process is more cumber-some and difficult to exclude excipients vitamin C compound interference; higher spectrophotometry, HPLC, TLC scan-ning method of measuring instruments, and increased testing costs. In this paper, methods of physics, by means of linear regression theory, the use of vitamin C in different pH solution in the optical rotation were significantly different, and the differential characteristics of the optical rotation and a linear relationship between concentration within a certain range, by difference show the polarimetry VC injection of content were measured at the same time to study and analyze the influencing factors of the experiment. The results show that the VC injection in 2.50 mg/ml. To 12.5 mg/ml concentra-tion and differential optical rotation of the linear relationship, the related equation y = 0.1835 x + 0.0113, the correlation coefficient r = 0.996. Compared with other measurement methods, the method is simple and reliable, the result is rea-sonable, so as to achieve fast, simple and accurate determination of the purpose of the VC content, especially for small and medium-sized hospital departments for the rapid detection of drugs.
关于京津冀交通一体化建设的几点思考
Thoughts on traffic integration of Beijing-Tianjin-Hebei

杜彦,高阳,
- , 2018, DOI: 10.11860/j.issn.1673-0291.2018.01.001
Abstract: 摘要 在京津冀协同发展战略的实施过程中,交通运输起着基础先导作用,实现交通一体化是京津冀协同发展的重要保障.本文通过分析具有代表性的东京、伦敦和纽约3个世界级城市群交通体系,在借鉴世界发达国家城市群交通一体化的先进理念和经验的基础上,总结了综合交通体系的构架和发展特征;针对目前京津冀地区区域交通发展中存在的问题,提出了关于京津冀交通一体化方面的一些思考,对于京津冀城市群交通系统的规划和建设具有积极的指导和借鉴作用.
Abstract:The transportation plays a fundamental role in the implementation process of coordinated development of Beijing-Tianjin-Hebei, and the implementation of traffic integration is an important guarantee for the coordinated development of Beijing-Tianjin-Hebei. In this paper, the world class traffic system of Tokyo, London and New York metropolis agglomeration are analyzed, and the advanced concepts and experiences of the traffic integration are learned from urban agglomerations in the developed countries. The structure and development characteristics of the integrated transportation system are concluded. On this basis, several thoughts on traffic integration of Beijing-Tianjin-Hebei are proposed for these problems in regional traffic, which will be the positive guidance for the planning and construction of the Beijing-Tianjin-Hebei transportation system.
铁基形状记忆合金防松螺母防断机理的数值分析
李俊,杜彦,
工程力学 , 2005,
Abstract: 由于铁基形状记忆合金材料本身的特殊性能,由其制成的螺母所组成的螺栓联接中,不仅螺纹副之间的自锁摩擦力矩有所提高,而且轴向载荷在各螺纹齿间分布的均匀性也得以改善,从而有效地防止了螺纹联接松动、松脱及疲劳断裂等失效现象的发生.主要对这种新型螺母的防断机理进行了分析,建立了螺栓联接载荷分布的计算模型,并通过与普通螺栓联接的比较,对这种新型螺母的防断性能进行了评价.
现场钻杆快速漏磁检测方法研究
Research for Fast MFL Testing Methodology of Field Drill Pipe
 [PDF]

刘世伟, 王增,, 燕华, 陈少波, 唐锐
Mechanical Engineering and Technology (MET) , 2015, DOI: 10.12677/MET.2015.42010
Abstract:
石油钻具特别是钻杆的现场快速检测一直是该行业所进一步期待的技术,以便更能节省时间减少工人劳动强度及成本,提高经济效益。首先分析了多类型缺陷的漏磁检测原理及现场钻杆快速检测问题,然后进一步地针对现场钻杆料架的堆放方式,在已有固定式钻杆检测设备和移动式钻杆检测装置的基础上,提出了现场钻杆原地整体磁化多杆并行的漏磁检测方法,并通过建模仿真计算进行了讨论与分析证明了其可行性,该方法直接在料架上对多根钻杆进行同时磁化检测,无需钻杆的大空间距离移动,减少了操作程序及劳动强度,节省了检测时间及检测成本,具有一定的优越性。
Oil drilling tools especially for the fast field detection of drill pipe is always the expected technique in relevant industries, which can further save the working time, labour intensity of workmen as well as the cost and thereby improve economic effectiveness. This paper analysed the MFL testing principles for various kinds of defects and the problems regarding to the fast speed field drilling pipes firstly, and then aiming at the stacking mode, proposed a method of MFL testing for multi field drilling pipes by overall magnetization concurrently on the basis of existing fixed and mobile detection device. Discussion is conducted and feasibility is confirmed by modeling and simulation. According to the proposed method, multi-drilling pipes are magnetized and detected simulta-neously on the shelf directly without needing to move the drilling tools in large space distance, which decreased the operation process and labor intensity tremendously as well as saved the de-tection time and cost with superiority to some extent.
基于普通光纤的螺旋缠绕式准分布光纤传感器的研究
杜彦,金秀梅,,魏斌
工程力学 , 2004,
Abstract: 针对用传统测试方法难以有效实现大型结构应力状态的分布测试问题,提出采用螺旋缠绕式光纤应变传感器进行测试的新方法.建立了此种光纤传感器的理论模型,对其传感原理进行了理论分析,并进行了实验研究,证明了其可行性.该传感测试方法为大型结构特别是预应力混凝土结构中预应力筋的应力分布测试提供了新的解决思路.
甲醇催化膜电极性能的研究
程祖,敦明,李文
环境化学 , 2015,
Abstract: 本文对甲醇催化膜电极继续进行了研究。在原有的铂-铑催化膜电极基础上,较系统地研究了铂钯(10—100%Pd)体系;铂铑(15—45%Rh)体系;以及铂-钯加贱金属体系。分别考查了催化膜电极的灵敏度、响应时间、干扰性能;并使用扫描电镜,X-射线光电子能谱,X-射线衍射等多种物理分析方法对催化膜电极表面状态进行了研究,验证了响应曲线的动力学过程,甲醇在电极上的氧化反应是属于一级动力学响应。据此筛选出较合适的甲醇催化膜电极。
不同工况条件下双泉水库溢洪道衬砌裂缝分析
,,张宾
南水北调与水利科技 , 2015,
Abstract: 随着混凝土在工程中的广泛应用,其裂缝问题也越来越受到人们的重视,由于施工或其它外界因素造成的裂缝,不仅影响结构的美观,而且由于裂缝造成抗渗性能的下降,引起漏水,还会影响结构的正常使用功能。以安阳县双泉水库溢洪道混凝土衬砌为工程实例,建立了基于ansys的有限元模型,通过施加不同的工况,分析其温度场、应力场的变化规律,研究了混凝土衬砌裂缝产生的原因及裂缝产生的初始位置,并且提出了对混凝土温度应力控制的措施。
基于正交试验法的27simn钢车削力研究
,剑飞?,陈五一?,王 威?
河北科技大学学报 , 2015, DOI: 10.7535/hbkd.2015yx06001
Abstract: 为了研究难加工材料27simn钢的切削规律,采用硬质合金车刀,利用正交法对27simn钢进行切削实验,得到切削参数在一定范围内(切削深度:0.3~0.8mm,进给量:0.08~0.2mm/r,转速:200~400r/min)与3个方向切削力的关系,结合线性回归方法得到三向切削力的经验模型。实验结果表明,切削深度对切削力的影响最大,其次是进给量,切削速度影响较小。切削深度和进给量对切削力的影响均是正相关,转速大于320r/min时,切削力随着切削速度的增大而减小。显著性检验结果表明切削力经验公式高度显著。
Taurolidine联合X射线对小鼠恶性黑色素瘤细胞周期进程的影响
, 张矛, 刘林林, 张伟静, , 龚守
吉林大学学报(医学版) , 2011,
Abstract: 目的:观察taurolidine联合X射线照射对小鼠恶性黑色素瘤(B16-4A5和B16-F10)细胞周期进程的影响,探讨其诱导肿瘤细胞凋亡的发生机制。方法:选择B16-4A5和B16-F10细胞系按给药浓度随机分为4组,taurolidine剂量分别为0、25、50和100?μmol.L-1,同时进行1、2和4GyX射线照射,采用流式细胞术检测细胞凋亡率和细胞周期,Westernblotting分析cyclinB、cdc2和caspase-3的表达。结果:与25?μmol.L-1taurolidine组比较,50和100?μmol?L-1taurolidine组诱导B16-4A5和B16-F10细胞发生G0/G1期阻滞,细胞数分别升高54.9%、73.7%和36.8%、55.5%(P<0.05);50?μmol.L-1taurolidine联合2和4GyX射线照射组,细胞G2/M期阻滞消除,细胞数分别降低52.1%、44.2%和59.3%、52.7%(P<0.05)。与对照组、单纯taurolidine组及单纯照射组比较,联合4GyX射线照射组cyclinB和cdc2的表达降低,caspase-3的表达升高(P<0.05)。结论:taurolidine联合X射线照射可去除G2/M期阻滞,可选择地抑制肿瘤细胞cyclinB和cdc2的表达、增强caspase-3的表达,共同诱导细胞凋亡。
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