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阮鸣 《南京晓庄学院学报》2014,(6):50-53
目的：建立高效液相色谱联用示差折光检测器测定冠心宁注射液中果糖、葡萄糖和蔗糖含量的方法.方法：Hanbon Lichrospher NH2分析色谱柱（5μm,4.6×250 mm）,Welchrom氨基保护柱（5μm,10 mm×4.6 mm）,流动相为乙腈—水（70∶30）,柱温：30℃,流速：1.0 ml/min,示差折光检测器设定温度：35℃.结果：回归方程A果糖=85 539C＋677.38,r=0.999 9,A葡萄糖=84 012 C＋575.37,r=1,A蔗糖=187 714C＋504.15,r=1（n=6）,果糖浓度在33.72~1 079μg/ml之间、葡萄糖浓度在32.22~1 031μg/ml之间以及蔗糖浓度在16.19~518μg/ml之间线性关系良好;平均回收率分别为100.1%、100.6%和99.3%,RSD分别为1.99、2.35和2.84%（n=6）;注射液中果糖、葡萄糖和蔗糖的总含量占固含物的55.03%.结论：该方法简便快速、准确可靠,可用于冠心宁注射液中果糖、葡萄糖及蔗糖的含量测定. 相似文献
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基于ABAQUS有限元分析方法,对两种热处理工艺下的16 Mn钢中MnS夹杂物在同一拉伸载荷作用下的应力和应变分布进行了研究。结果表明,两种晶粒尺寸的材料在长条形MnS夹杂物附近存在着垂直于加载方向的X形状的Mi-ses应力和PEEQ集中区。但细晶的16Mn钢中MnS引起的应力和应变集中程度要明显大于粗晶的16Mn钢中MnS引起的应力和应变集中,其原因与细晶强化有关。 相似文献
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利用灰色关联分析方法研究粉煤灰的粒度分布对水泥性能的影响．结果表明：O～5μm、5～10μm粉煤灰颗粒分别是水泥3d、28d抗压强度的最强影响因子;水泥3d、28d强度随小于33μm的粉煤灰颗粒含量增大而提高,随大于33pm的粉煤灰颗粒含量增大而降低;可以通过优化粉煤灰的粒度分布来改善水泥性能． 相似文献
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采用二硝基苯肼衍生-高效液相色谱法测定水发物食品中甲醛的含量.选择diamonsirC18柱（5 μm,250 mm×4.6 mm）色谱柱,流动相为V（甲醇）∶V（水）=（5.5∶4.5）,流速为1.0 mL·min^-1,检测波长为357 nm,进样量为10μL,对水发物中甲醛的含量进行检测.结果表明：甲醛在0.0063 ～0.1260 μg范围内呈良好的线性关系,r =0.9991;平均回收率为105％;该方法简便、准确、重现性好. 相似文献
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通过对钢铁材料的含碳量分布与磁化特性关系的分析,发现钢铁材料的矫顽力与其含碳量关系最为密切,进而研究了通过矫顽力来测量钢铁材料的渗碳层深度的方法;进行了钢铁材料矫顽力自动检测系统的设计,给出了单片机控制系统的结构及主程序流程. 相似文献
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The deviation of flow characteristics from the predictions of the conventional theory for microtubes was attributed to the change of fluid viscosity resulted from the interactions between the molecules on solid wall and in fluid. The degree of this departure is dependent on the microtubes materials. A concept of equivalent thickness with which conventional theory can be used to predict the flow in microtubes without modifying the fluid viscosity was put forward. The values of equivalent thickness for fused silica and stainless steel materials were determined as 1.8 μm and 1.5 μm, respectively, by repeated numerical simulation. 相似文献
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我们所研制的含钙易切钢(40 CrCa)的可加工性具有一个明显的特点,即在某一切削速度范围内,这种钢的可加工性是随着切削速度的提高而改善的。当切削速度V≈200米/分时,可加工性达到最佳状态。此时刀具的耐用度为切削普通钢(40Cr)时的8倍。 这种易切钢的可加工性特别好的原因在于:用钨、钛、钴类硬质合金刀具(YT15)以高的切削速度切削这种钢时,钢中的球状氧化夹杂物会软化,并且沉积在刀具表面上形成一层薄膜,这层薄膜对刀具的磨损有阻碍作用。 相似文献
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人体呼出气溶胶在封闭环境中的分布特性 总被引：1，自引：0，他引：1
研究了1.0～10.0μm的呼吸道颗粒物在混合送风、置换送风和地板送风的办公室环境中的浓度空间分布和瞬态演变规律.仿真结果表明：小于10.0μm的飞沫在混合送风的房间内几乎是均匀分布的.然而,在置换送风和地板送风中,垂直温度梯度使得小于10.0μm的飞沫在人体呼吸区高度聚集,导致一个较高的浓度水平,因此室内人员被感染的概率比较高.由咳嗽或者打喷嚏产生的飞沫在置换和地板送风中的稀释（浓度衰减）比在混合送风中慢,这是因为置换和地板送风中人体呼吸区的风速比较小,飞沫在此聚集,不易被气流携带排出室内空间. 相似文献
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以Si衬底上外延Ge薄膜为吸收区,研究了Si基Ge光电探测器的材料生长与器件制作工艺,并对材料晶体质量和器件性能进行表征分析。Ge薄膜是采用低温缓冲层技术在超高真空化学气相沉积系统上生长的。1μm厚Ge薄膜的表面仅出现纳米量级的岛,表面粗糙度只有1.5 nm。Ge薄膜的X射线衍射峰形对称,峰值半高宽低于100 arc sec。Ge薄膜中存在0.14%的张应变。Si基Ge光电探测器在-1 V偏压时暗电流密度为13.7 mA/cm2,在波长1.31μm处的响应度高达0.38 A/W,对应外量子效率为36.0%,响应波长扩展到1.6μm以上。 相似文献
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热镀锌板在冲压成零件时,局部的镀锌层出现约3mm大小的起泡,将起泡用手术刀切开,撕下锌层,采用扫描电镜对起泡部位的基体以及锌层靠基体的表面进行了分析,对比分析正常部位纯锌层与基体之间的抑制层。结果表明:正常部位的抑制层为细小弥散分布的Fe2Al5颗粒,产生起泡的缺陷部位未见到抑制层颗粒,锌层与基板之间存在局部聚集的Al2O3夹渣,冲压成型后,夹渣松动,锌层与基板分离,导致锌层起泡。 相似文献
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采用水蒸气蒸馏法对黄瑞香干燥叶片挥发油进行提取,运用毛细管气相色谱-质谱联用法结合计算机检索对黄瑞香干燥叶片挥发油进行成分分析和鉴定,经毛细管色谱分离出68个峰,并确认了这68种化合物,所鉴定化合物的含量占全油的99.51%.用气相色谱面积归一化法测定了各组分的相对百分含量.其化学成分主要为:3-己烯-1-醇、顺式-α,α,5-三甲基-5-四氢呋喃-2甲醇、天然壬醛、十六烷、二噻吩乙酸,3-三癸酯、柏木脑、2-乙氧基丁烷、β-紫罗酮、1-乙氧基丙烷、苯乙醛、6,10-二甲基-5,9-十一双烯-2-酮、十五烷、(2R,3R)-(-)2,3-丁二醇、杜松烯、六氢合金欢丙酮、(E)-呋喃基芳樟醇氧化物,以上十六种化合物占其挥发油总量的66.78%.利用滤纸片扩散法研究山胡椒挥发油对7种常见食源性污染菌的抑菌作用,并探讨加热处理对水蒸汽蒸馏法所得挥发油抑菌活性的影响.实验表明,所得挥发油对6种污染菌都有抑制作用,而且加热处理对水蒸汽蒸馏法所得黄瑞香干燥叶片挥发油的抑菌效果无明显影响. 相似文献
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为了研究稀土元素对中碳钢冲击韧性的影响,利用真空感应炉熔炼稀土合金化的S50C钢进行冲击韧性测试。应用JB-30B冲击试验机测定钢试样的冲击功,并通过SEM和EDS检测手段分析稀土元素对S50C钢微观结构的影响。结果表明,与未含稀土元素的钢试样相比,含有微量稀土元素（0.003 5%）的钢试样冲击功增加了0.45倍;晶粒明显细化,珠光体数量减少,软相的铁素体组织增多,且连成柔性的网状,同时钢中夹杂物由多面形改变为尺寸更小的球面形。 相似文献
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综述了国内外相关资料,介绍了钢铁材料耐蚀研究方法,阐述了钢中合金元素、夹杂物对耐蚀性的影响。指出了通过冶炼轧制工艺控制钢中夹杂的形态与分布,进行低生产成本耐蚀钢研究的思路。 相似文献
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The spatial distribution of extracellular polymeric substances (EPS) in a pilot-scale membrane bioreactor (MBR) was studied. The sampling points on top of and inside the membrane module were measured and analyzed by the experimental variant function. The content of EPS was spatially interpolated by ordinary Kriging method, and illustrated with SURFER software. A case study was carried out in an MBR with membrane aperture of 0.4 μm and handling capacity of 120 m3/d in Jizhuangzi sewage treatment plant, Tianj... 相似文献
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乳化剂对壳聚糖微球形成的影响 总被引：2，自引：0，他引：2
何强芳 《广东教育学院学报》2005,25(3):67-70
以壳聚糖溶液为分散相，戊二醛为交联剂，真空泵油和石蜡油相混合为连续相，通过油包水乳液分散-化学交联法制备医药载体壳聚糖微球．研究了乳化剂的种类和浓度对壳聚糖微球性状和形态的影响．实验结果表明，乳化剂的种类和浓度对微球的形成影响很大．在Span-80和硬脂酸镁以质量比3：1相复合为乳化剂及总乳化剂浓度在10～20g／L的条件下，所获得的微球球形规整，分散性好，粒径分布在1～5μm之间． 相似文献
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杨晓静凌静秀银光球 《福建工程学院学报》2017,(1):30-34
基于虚拟样机技术及有限元法,提出了破碎站钢结构的力学模型等效及落料冲击系数的数值模拟方法,采用理论公式对单块物料冲击钢结构的动载系数进行计算,并将其与数值模拟分析结果对比。分析表明,1m3大小的正方体煤岩物料从5m高度下落直接冲击钢结构,其冲击系数的理论计算及刚体动力学分析结果均为123,而柔体动力学分析结果为125,三者误差约1.6%,表明提出的数值模拟方法及钢结构等效模型有效,分析方法可为破碎站的性能评估及结构优化提供基础。 相似文献
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The spatial distribution of extracellular polymeric substances （EPS） in a pilot-scale membrane bioreactor （MBR） was studied. The sampling points on top of and inside the membrane module were measured and analyzed by the experimental variant function. The content of EPS was spatially interpolated by ordinary Kriging method, and il- lustrated with SURFER software. A case study was carried out in an MBR with membrane aperture of 0.4 ~tm and handling capacity of 120 ma/d in Jizhuangzi sewage treatment plant, Tianjin. From the visualization of EPS distribu- tion, it is seen that on the horizontal plane, the content of EPS was the lowest at the center; and on the vertical plane, the content of EPS decreased with the increase of depth. The shearing force caused by aeration of perforated pipe and the influent mode are the main influencing factors for this distribution. 相似文献
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RH和RH-KTB精炼过程中钢液流动和混合特性的研究 总被引：7，自引：0，他引：7
The flow and mixing characteristics of molten steel during the vacuum circulation refining,including RH(Ruhrstahl-Heraeus) and RH-KTB(Ruhrastahl-Heraeus-Kawasaki top blowing) processes,were investigated on a 1/5 linear scale water model of a 90t multifunction RH degasser,The circulation rate was directly and more accurately determined,using a new method by which the more reliable results can be obtained.The fluid flow pattern and flow field in the ladle were demonstrated,observed and analyzed.The mixing time of liquid in the ladle was measured using electrical conductivity method.The residence time distribution in the RH model was obtained by tracer response technique.The influence of the main technological and geometric factors,including the gas top blowing*(KTB) operation,was examined.The results indicated that the circulation rate of molten steel in the RH degasser can be fairly precisely calculated by the formula:Q1p=0.0333Qg^0.26Du^0.69Dd^0.80(t/min),where Qg-the lifting gas flow rate(NL/min);Du and Dd-the inner diameters of the up and down-snorkels(cm),respectively.The maximum value of circulation rate of molten steel in the case of the 30cm diameters either of the up-and down-snorkels for the RH degasser(the “Saturated” rate) is approximately 31 t/min.the corresponding gas flow rate is 900NL/min.Blowing gas into the vacuum chamber through the top lance like KTB operation does not markedly influence the circulatory flow and mixing charateristics of the RH process under the conditions of the present work.There exist a major loop and a large number of small vortices and eddies in the ladle during the RH refining process.A liquidliquid two-phase flow is formed between the descnding stream from the down-snorkel and the liquid around the stream.All of these flow situation and pattern will strongly influence and determine the mixing and mass transfer in the ladle during the refining.The correlation between the mixing time and the stirring energy density is τmε^0.50 for the RH degasser.The mixing time rapidly shortens with an increase in the lifting gas flowrate.At a same gas flow rate,the mixing times with the up-and down-snorkel diameters either of 6 and 7cm are essentially same.The 30cm diameters either of the up-and down-snorkels for the RH degasser would be reasonalble.The concentration-time curve showed that three circulation cycles are at least needed for complete mixing of the liquid steel in the RH degasser. 相似文献
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This paper presents the research on the atmospheric corrosion rates of carbon steel, zinc and copper in Chongqing, which was a corrosion subprogram of an international project, Regional Air Pollution in Developing Countries. We performed field exposure tests of carbon steel, zinc and copper at an urban site Guanyinqiao and a rural site Tieshanping inChongqing, then used grey relational analysis, based on the database of the whole corrosion project, to determine the order of the effect of environmental factors on corrosion rates of tested metals, and established dose-response functions for these three metals. The results showed that the two crucial agents of acidic environment, SO2 and H , were common factors that contributed most to the corrosion of the tested metals. The established dose-response functions for outdoor carbon steel and zinc are proved applicable to use in Chongqing, but the function for copper needs further modifying. We employed these dose- response functions and general environmental data to elaborate the maps of corrosion rate respectively of carbon steel and zinc by geological information system (GIS) technique which help to identify areas of high corrosion damage risk. An acceptable annual average SO2 level of 21 μg/m3 for carbon steel and that of 61 μg/m3 for zinc are also put forward to control the air pollution impact on atmospheric corrosion in Chongqing urban areas. 相似文献