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1.
Five novel monoazo disperse dyestuffs based on N‐ester‐1,8‐naphthalimide were synthesized. Acenaphthene was nitrated, then oxidized to 4‐nitro‐1,8‐naphthalic anhydride. 4‐Nitro‐1,8‐naphthalic anhydride was reacted with methyl and ethyl glycinate in alcoholic media, followed with reduction. 4‐Amino‐N‐methyl and ethyl glycinate‐1,8‐naphthalimide were obtained. These products were diazotized and coupled with appropriate aromatic amines to give bluish‐red or violet dyestuffs. All intermediates and dyestuffs were purified and characterized by 1H‐NMR, FTIR, DSC, UV‐VIS and Elemental Analysis. Dispersion of dyestuffs was prepared in water and applied to polyester fabrics. The dyed fabrics showed that four of the synthesized dyestuffs were suitable for coloring polyester fibers, producing deep bluish red with very good build up properties.  相似文献   
2.
Reversed phase liquid chromatography with diode array detection (DAD) and electrospray mass spectrometric (ESI MSD) methods were developed for the identification of anthraquinone color components of cochineal, lac dye, and madder – red natural dyestuffs. Electrospray mass spectrometry was found to be more suitable than diode array detection for such analysis because of its higher sensitivity (detection limits in the range 30–90 ng mL–1) and selectivity. The developed method permitted unequivocal identification of carminic acid and laccaic acid A as coloring matters in examined preparations of cochineal and lac dye, respectively. In madder more chemical color species were found: alizarin, purpurin, lucidin, ruberythric acid, and also aluminum and calcium alizarin lake. Among the methods recommended so far, the present one allows fast, direct, and unequivocal identification of components of very complicated natural products used in art.  相似文献   
3.
建立了快速高效液相色谱-串联质谱法(RRLC-MS/MS)同时测定水产品中四环素类、喹诺酮类、磺胺类、磺胺增效剂和三苯甲烷类共5大类33种药物残留的方法。样品用Na2EDTA-Mcllvaine缓冲溶液及乙腈提取,正己烷脱脂后,用RRLC进行分离。在电喷雾正离子模式下,以动态多反应监测(Dynamic MRM)方式采集数据进行定性与定量分析。33种药物在相应的浓度范围内线性良好,相关系数均大于0.99;在3个不同浓度添加水平下,平均回收率为63.6%~115.2%;相对标准偏差(RSD)为4.6%~14.6%;检出限(LOD,S/N=3)和定量限(LOQ,S/N=10)分别为0.1~2.0μg/kg和0.5~5.0μg/kg。本方法简便快速、灵敏可靠,适用于水产品中药物多残留的同时快速定性与定量测定。  相似文献   
4.
卡尔曼滤波光谱法用于化学平衡研究   总被引:1,自引:0,他引:1  
提出了光谱法与卡尔曼滤波及因子分析相结合的新方法以研究化学平衡,将复杂的化学平衡视为特殊的多组分混合体系,其中各物种在不同介质中存在相互的平衡,卡尔曼滤波及因子分析被用作有效的化学计量学分辨工具,从光谱数据中提取信息,已用于确定所存在的物种数目和浓度以及平衡常数,本文以部分三苯甲烷试剂为例确定其酸碱平衡常数。  相似文献   
5.
采用液相色谱-串联质谱法对鱼肉和虾肉中三苯甲烷类与噻嗪类染料及其代谢物进行测定。样品经对甲苯磺酸-乙酸铵-乙腈溶液提取,正己烷脱脂,二氯甲烷萃取,MCAX固相萃取净化后,以Waters BEH C18色谱柱为分离柱,以0.15%甲酸溶液(含5mmol·L-1乙酸铵溶液)-乙腈混合液为流动相进行梯度洗脱,采用电喷雾正离子源及多反应监测模式进行测定。各化合物的质量浓度在20.0μg·L-1以内呈线性,方法的测定下限(10S/N)均为0.5μg·kg-1。对空白样品进行加标回收试验,回收率在62.6%~108%之间,测定值的相对标准偏差(n=6)在2.0%~14%之间。方法用于鱼肉和虾肉样品的检测,结果与国家标准方法的测定值一致。  相似文献   
6.
7.
A simple and sensitive method was developed for the rapid analysis of cationic dyestuffs from river and industrial wastewater using functionalized-multiwalled carbon nanotubes (f-MWCNT) with atmospheric pressure-matrix assisted laser desorption/ionization mass spectrometry (AP-MALDI/MS). The separation and preconcentration of analytes from sample solution was based on electrostatic force of attraction between positive dyestuffs and negatively charged f-MWCNT. The optimum enrichment of the three dyestuffs was observed at pH 5.0 for 3 min contact time and using 1 mg f-MWCNT in 1 mL water sample. The developed method has been successfully applied for the determination of three cationic dyestuffs namely neutral red (NR), brilliant cresyl blue (BB), and methylene blue (MB) in real world samples including river and industrial wastewater. The relative recoveries of dyestuffs from water sample were in the range 88.6-98.4%, indicating that the matrix had little effect on enrichment of analytes. The LOD and LOQ for cationic dyestuffs in water were 0.5-1.9 and 1.6-6.0 microg/L, respectively. All the results indicated that the proposed method could be used for the simultaneous determination of the three cationic dyestuffs in river and industrial wastewater at trace levels without the need of any chromatographic separation techniques.  相似文献   
8.
Triphenylmethane (TPM) was used as the initiator-transfer-terminator agent (iniferter) for the pseudo-living radical polymerization of methyl methacrylate (MMA) in cyclohexanone (CHO) for the first time. The pseudo-living radical polymerization of styrene is also investigated for comparison. The polymerizations both exhibit a linear increase of number molecular weight (Mn) with conversion and the obtained polymer can be utilized as a macroinitiator for the successful chain extension. Other factors such as polymerization temperature and the molar ratio of monomer-to-iniferter were investigated and the polymerization results also showed pseudo-living characteristics. Furthermore, other triarylmethanes with substituents, such as tris-(p-acetylphenyl) methane (TAcPM) and tris-(p-carboxyphenyl) methane (TCOPM), were also employed. The results further confirmed that the other compounds with similar structure can also be used as the iniferter.  相似文献   
9.
Pigments are among the most important components of historical paintings and textiles and their nature provides the unique character of color. They can be divided into two main groups: inorganic and organic, extracted from plants or animals. Their identification is a necessary stage in the conservation of art objects. Reversed-phase liquid chromatography with electrospray ionization mass spectrometry (ESI-MS) and UV/visible spectrophotometric methods were elaborated for the identification of indigoid (indigo, indirubin, isoindigo, isoindirubin) color components of natural dyestuffs and their natural or synthetic precursors (indican, isatin, indoxyl, 2-indolinone). ES-MS offers detection limits in the range 0.03-5.00 microg ml(-1) for the color compounds examined. The method developed made it possible to identify indigo and its isomers in genuine Indian indigo, indigo from woad and Tyrian Purple. It was applied to the identification of natural dyes on fiber from a 19th century Japanese tapestry, 'Cranes in the landscape'. A procedure based on freezing and grinding of a sample before the extraction of dyes from the textile was developed. The components of the extract obtained were identified after acidic hydrolysis as indigotin and methylene blue.  相似文献   
10.
建立了同时测定玩具中16种致癌和致敏染料(酸性红26、碱性红9、分散蓝1、酸性紫49、分散蓝3、溶剂黄1、分散蓝106、分散橙3、分散黄3、碱性紫1、碱性紫3、分散红1、溶剂黄3、分散蓝124、溶剂黄2、分散橙37)的超高效液相色谱-串联质谱分析方法。纺织品、皮革、纸张、木材、气球、造型黏土、贴纸、可接触液体等不同类型的玩具材料经超声提取后,以Waters ACQUITY UPLC BEH C18色谱柱(50mm×2.1mm,1.7μm)分离后进行UPLC/MS/MS多反应监测模式下的定性及定量分析。16种致癌和致敏染料的方法检出限为1.0~8.0μg/kg;在5~100μg/kg范围内的低、中、高3个添加水平的平均回收率为81.3%~98.6%;日内精密度均小于11%,日间精密度均小于14%。本方法准确、快速、灵敏度高,可用于玩具的实际检验工作。  相似文献   
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