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以Cu+催化叠氮炔环偶极加成点击化学反应,在不同催化剂(CuBr/五甲基二乙烯三胺或CuSO4·5H2O/抗坏血酸钠)和反应温度(55,65,75℃)下制备三唑环基含氟芳香烃改性纳米氧化锌(ZnO-sTRF),研究了不同ZnO-sTRF的化学结构和元素组成;将表面接枝量最高的ZnO-sTRF与聚氨酯(PU)复合制备ZnO-sTRF/PU涂层,研究了该涂层的疏水性能、抗菌性能以及防污性能。结果表明:当催化剂为CuSO4·5H2O/抗坏血酸钠,反应温度为75℃时,改性纳米ZnO表面接枝量最高,制备的ZnO-sTRF/PU涂层表面水接触角可达105.4°,表面大肠杆菌、金黄色葡萄球菌和假交替单胞菌的死菌面积覆盖率是ZnO/PU涂层和3-氨丙基三乙氧基硅烷改性ZnO/PU涂层的10倍以上;在实际海洋环境中浸没120 d后,涂层表面无明显硬质生物的附着。 相似文献
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人体血浆中西布曲明及其活性代谢产物的HPLC-MS/MS测定方法研究 总被引:4,自引:0,他引:4
采用高效液相色谱 -串级质谱 (HPLC-MS/MS)法测定人体血浆中西布曲明及其两种活性代谢产物浓度。以安定为内标 ,用乙醚提取 ,流动相为 V(甲醇 )∶ V(乙酸铵 )∶ V(甲酸 ) =85∶ 7.5∶ 7.5 ,质谱扫描方式为多反应离子监测 (MRM)。结果表明 :西布曲明及其两种活性代谢产物的平均相对回收率均在 92 .7%~1 0 3 .0 % ,日内、日间标准偏差 sr均小于± 1 5 % ,浓度在 0 .0 5~ 2 5 μg/L范围 ,线性关系良好。本方法灵敏度高 ,特异性强 ,保留时间短 ,适合于药物代谢动力学的研究 相似文献
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本文主要采用薄层色谱 荧光检测法对中药材中西维因及其降解产物浕 萘酚的残留量进行测定。采用环己烷∶丙酮∶正丙醇∶苯 =13∶2∶2∶3(V/V)作为展开剂 ,西维因和浕 萘酚的Rf 值分别为 0 4 4和 0 72 ,在 313nm条件下进行荧光测定 ,在 0 0 0 4~ 0 0 80 4mg/mL和 0 0 0 0 6~ 0 0 0 5 7mg/mL的浓度范围内 ,线性相关系数均为 0 999,检测限分别为80 4 8ng和 3 4 6ng。用本方法测定地骨皮样品 ,西维因和浕 萘酚的加标回收率分别为83 3%和 10 0 % ,适于西维因及其降解产物的含量测定和质量控制 相似文献
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采用直流电弧等离子体法 ,分别在 1个大气压的H2 +Ar和CH4+He混和气氛中制备了Fe、Ni、Fe-Ni合金磁性超微粒子 (UFP)。利用Fe、Ni、Fe-Ni合金超微粒子 ,选择适当的表面活性剂和载液 ,制备了高粘度磁性液体(ML) ,常温 (2 5℃ )粘度为 (2 6~ 6 0 )× 10 5mPa·s,高温 (85℃ )粘度为 (1 0~ 3 2 )× 10 5mPa·s,室温下饱和磁化强度为FeML 2 4 0 8~ 6 8 0 0Am2 /kg,NiML 10 19~ 17 83Am2 /kg,Fe-NiML 2 6 2 1~ 75 13Am2 /kg 相似文献
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祖英纯 《机械工人(冷加工)》1982,(6)
PS-15动平衡机桥架原结构如图1,由V型块1、弹簧片2、磁力传感器3、传感器螺杆4、螺杆5和压紧块6等组成。当做动平衡时,将待平衡的转子放在V型块1上,由于不平衡量的影响,通过弹簧片2振动,传感器螺杆4随之振动。当停止时,需扭动螺杆5,使压紧块6压紧V型块1。再做动平衡时,再扭动螺杆5,松开压紧块6。这样锁紧和 相似文献
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《起重运输机械》2003,(1)
一、制动器统计日期 :2 0 0 2 10 31 序号企业名称、电话获证产品型号规格认可证书编号有效期1海阳市田丰机械制造有限公司(0 5 35 ) 32 5 84 78制动器YWZ4 0 0及以下RK990 0 12至 2 0 0 2 12 92 重庆市双鹰制动器有限公司(0 2 3) 6 885 6 319液压制动器YWZ系列 (10 0 4 0 0 )XS2 0 0 1 10 0 3至 2 0 0 3 12 2 53新乡市科兴制动器有限公司(0 373) 87374 88电磁块式制动器电力液压块式制动器TJ2A系列30 0及以下YWZB系列4 0 0及以下XS2 0 0 1 10 0 8XS2 0 0 1 10 0 7至 2 0 0 4 2 144 象山港口制动器… 相似文献
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以锌粉、铝粉为原料,硝酸镧为添加剂,制备了硝酸镧改性无铬达克罗涂层,研究了改性涂层在质量分数5%NaCl溶液中浸泡后的腐蚀产物物相组成和微观形貌,探究了涂层的腐蚀行为和防腐机理。结果表明:在NaCl溶液中浸泡10 d后,涂层中部分富锌相优先腐蚀形成Zn5(OH)8Cl2·H2O,表面呈蜂窝状形貌;浸泡30 d后,腐蚀产物增多,生成Zn5(OH)6(CO3)2,表面呈海绵状结构;浸泡60 d后,腐蚀产物逐渐溶解、剥落,表面呈三维多孔网络结构。涂层的防腐机理包括腐蚀产物和稀土钝化膜的自修复作用、有机硅烷钝化膜和片状锌铝粉分层堆叠的物理屏蔽作用、锌和铝金属的牺牲阳极作用以及稀土钝化作用和缓蚀剂的缓释作用。 相似文献
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超临界流体色谱法在药物分析中的应用 总被引:1,自引:0,他引:1
超临界流体色谱法(supercritical fluid chromatography,SFC)是高效液相色谱法和气相色谱法的重要补充技术,用SFC可以分离多数不能用GC分离的低挥发性物质和不能用HPLC分离的无紫外吸收的物质。与传统的HPLC相比,具有高效快速、绿色环保的优点。本文介绍超临界流体色谱仪及色谱法的特点和优越性。并综述其在药物分析中的应用,主要介绍在手性药物、中药领域、代谢产物中的分析和应用。 相似文献
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LC/MS applications in drug development 总被引:9,自引:0,他引:9
The combination of high-performance liquid chromatography and mass spectrometry (LC/MS) has had a significant impact on drug development over the past decade. Continual improvements in LC/MS interface technologies combined with powerful features for structure analysis, qualitative and quantitative, have resulted in a widened scope of application. These improvements coincided with breakthroughs in combinatorial chemistry, molecular biology, and an overall industry trend of accelerated development. New technologies have created a situation where the rate of sample generation far exceeds the rate of sample analysis. As a result, new paradigms for the analysis of drugs and related substances have been developed. The growth in LC/MS applications has been extensive, with retention time and molecular weight emerging as essential analytical features from drug target to product. LC/MS-based methodologies that involve automation, predictive or surrogate models, and open access systems have become a permanent fixture in the drug development landscape. An iterative cycle of "what is it?" and "how much is there?" continues to fuel the tremendous growth of LC/MS in the pharmaceutical industry. During this time, LC/MS has become widely accepted as an integral part of the drug development process. This review describes the utility of LC/MS techniques for accelerated drug development and provides a perspective on the significant changes in strategies for pharmaceutical analysis. Future applications of LC/MS technologies for accelerated drug development and emerging industry trends are also discussed. 相似文献
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Controls in food industry are fundamental to protect the consumer health. For products of high quality, warranty of origin and identity is required and analytical control is very important to prevent frauds. In this article, the "state of art" of mass spectrometry in enological chemistry as a consumer safety contribute is reported. Gas chromatography-mass spectrometry (GC/MS) and liquid-chromatography-mass spectrometry (LC/MS) methods have been developed to determine pesticides, ethyl carbamate, and compounds from the yeast and bacterial metabolism in wine. The presence of pesticides in wine is mainly linked to the use of dicarboxyimide fungicides on vineyard shortly before the harvest to prevent the Botrytis cinerea attack of grape. Pesticide residues are regulated at maximum residue limits in grape of low ppm levels, but significantly lower levels in wine have to be detected, and mass spectrometry offers effective and sensitive methods. Moreover, mass spectrometry represent an advantageous alternative to the radioactive-source-containing electron capture detector commonly used in GC analysis of pesticides. Analysis of ochratoxin A (OTA) in wine by LC/MS and multiple mass spectrometry (MS/MS) permits to confirm the toxin presence without the use of expensive immunoaffinity columns, or time and solvent consuming sample derivatization procedures. Inductively coupled plasma-mass spectrometry (ICP/MS) is used to control heavy metals contamination in wine, and to verify the wine origin and authenticity. Isotopic ratio-mass spectrometry (IRMS) is applied to reveal wine watering and sugar additions, and to determine the product origin and traceability. 相似文献
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The role of mass spectrometry in the study of non-enzymatic protein glycation in diabetes: an update
Recent studies on non-enzymatic protein glycation are reviewed, and results are critically discussed. Advanced glycation end products (AGE) levels in the body reflect a balance between their formation and catabolism. AGE proteolysis leads to the formation of low-molecular-weight AGE (AGE peptides) that are normally excreted in urine. In the case of diabetic disease and/or renal failure, AGE peptides accumulate in plasma. Because of their high reactivity, these compounds have been thought to play a role in the progression of chronic complications. The structural identification of these compounds is particularly important, and a strategy has been designed for their possible definition. A series of experiments has been devoted to the study of the enzymatic degradation products of in vitro glycated human serum albumin (HSA). This approach, based on different MS methods (LC/ESI/MS, LC/ESI/FTMS, MALDI), led to the detection of the glycated peptides generated by digestion of HSA. A further study was devoted to the possible identification of the peptides identified in the glycated HSA digestion products in the plasma of diabetic and nephropatic subjects. No glycated HSA digestion products were found in plasma samples of the subjects under investigation even if clear differences were found among the LC runs from populations of healthy, diabetic, and nephropatic subjects. Parallel investigations were devoted to the evaluation of glyoxal and methylglyoxal-dicarbonyl compounds that originate at the intermediate stage of the Maillard reaction. This evaluation was performed in diabetic patients, before and after the achievement of good metabolic control, and in nephropatic patients subjected to peritoneal dialysis (PD). In the latter case, results indicated that these dicarbonyl compounds, already present in the dialysis fluids, show a decrease in plasma and in dialysis fluids; those data suggested their reaction at peritoneal membrane level. 相似文献
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电子产品弹性橡胶按键的典型结构设计 总被引:3,自引:0,他引:3
以按键的CLICK FEELING特性作为设计考虑的主要因素,阐述了电子产品弹性橡胶按键的典型结构设计方案,具有一定的实用价值。 相似文献
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采用LC/MS和LC-MS/MS法同时检测保健品中非法添加的伐地那非。用乙酸乙酯提取,以10 mmol•L-1的甲酸铵(pH 3.5)和乙腈为流动相,分别用Agilent Zorbax SB C18(150 mm×2.1 mm×5 μm)和Agilent Zorbax SB C18(100 mm×2.1 mm×3.5 μm)色谱柱分离,采用电喷雾离子源,正离子扫描方式进行分析检测。该方法简便、快捷、可靠,适用于保健品中非法添加伐地那非的常规检测。 相似文献
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Herbert Oberacher Florian Pitterl Robert Erb Sabine Plattner 《Mass spectrometry reviews》2015,34(1):64-92
Electrochemistry (EC) is a mature scientific discipline aimed to study the movement of electrons in an oxidation–reduction reaction. EC covers techniques that use a measurement of potential, charge, or current to determine the concentration or the chemical reactivity of analytes. The electrical signal is directly converted into chemical information. For in‐depth characterization of complex electrochemical reactions involving the formation of diverse intermediates, products and byproducts, EC is usually combined with other analytical techniques, and particularly the hyphenation of EC with mass spectrometry (MS) has found broad applicability. The analysis of gases and volatile intermediates and products formed at electrode surfaces is enabled by differential electrochemical mass spectrometry (DEMS). In DEMS an electrochemical cell is sampled with a membrane interface for electron ionization (EI)‐MS. The chemical space amenable to EC/MS (i.e., bioorganic molecules including proteins, peptides, nucleic acids, and drugs) was significantly increased by employing electrospray ionization (ESI)‐MS. In the simplest setup, the EC of the ESI process is used to analytical advantage. A limitation of this approach is, however, its inability to precisely control the electrochemical potential at the emitter electrode. Thus, particularly for studying mechanistic aspects of electrochemical processes, the hyphenation of discrete electrochemical cells with ESI‐MS was found to be more appropriate. The analytical power of EC/ESI‐MS can further be increased by integrating liquid chromatography (LC) as an additional dimension of separation. Chromatographic separation was found to be particularly useful to reduce the complexity of the sample submitted either to the EC cell or to ESI‐MS. Thus, both EC/LC/ESI‐MS and LC/EC/ESI‐MS are common. © 2013 The Authors. Mass Spectrometry Reviews published by Wiley Periodicals, Inc. Mass Spec Rev 34:64–92, 2015 相似文献
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采用液相色谱-质谱(LC/MS)技术鉴定匹多莫德的有关物质,选取Sepax GP-C8色谱柱(250 mm×4.6 mm×5 μm),以甲醇-三氟乙酸溶液为流动相,梯度洗脱,对匹多莫德有关物质进行分离;采用电喷雾正离子化-高分辨飞行时间质谱法(ESI-TOF MS)测定各有关物质离子的准确质量和元素组成,三重四极杆串联质谱(ESI-MS/MS)测定子离子特征。结果表明:在所建立的条件下,匹多莫德及其有关物质的分离良好,检测并鉴定出11个主要有关物质。该技术能有效地分离鉴定匹多莫德中的有关物质,其鉴定结果可为质量控制和工艺优化提供参考。 相似文献