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1.
建立了一种用稀盐酸溶解样品,标准工作溶液中匹配钾,ICP-AES测定高铼酸钾中19种杂质元素的方法。在选定的仪器工作条件下,样品加标回收率(%)分别为:钠94.4~101、钙98.8~102、铝98.1~102、镁95.8~99.1、钴98.4~101、钼97.3~103、钛97.6~102、钒96.6~106、锆96.2~97.7、铬97.8~101、铜98.1~108、铁92.9~104、锰95.5~98.4、镍93.6~101、钯93.3~101、铅96.5~103、锌95.2~103、铂95.9~99.9、铑94.5~96.3;方法精密度RSD%(n=7)分别为:钠2.0~5.5、镁1.1~3.5、铝0.9~2.5、钙1.5~7.3、钴1.1~3.1、钼0.9~4.5、钛1.0~2.8、钒1.6~4.0、锆1.4~3.6、铬0.77~4.6、铜0.74~1.8、铁1.3~3.8、锰1.1~2.0、镍0.99~5.0、钯1.1~2.4、铅1.3~9.1、锌0.80~6.7、铂1.2~10、铑0.78~8.6。方法简便、快速、准确, 满足生产分析要求。 相似文献
2.
以稻草秸秆快速热裂解生物油为样品,选取乙酸乙酯作为添加剂,按不同质量分数(分别为1%、6%、11%、16%和21%)添加到生物油中,考察原始生物油(空白组)及乙酸乙酯组生物油理化特性随贮存时间的变化规律。结果表明,随着乙酸乙酯添加质量分数增大,各乙酸乙酯组(1%、6%、11%、16%和21%)生物油最终pH值比空白组分别提高0.66%、2.33%、3.65%、4.32%和6.31%;最终含水率比空白组分别降低10.90%、20.17%、28.19%、30.27%和35.10%;最终运动黏度比空白组分别降低13.69%、39.08%、57.99%、66.00%和73.58%。FT-IR和GC-MS分析结果表明,添加乙酸乙酯能抑制生物油老化反应。此外,GC-MS分析结果还证实乙酸乙酯可以减少生物油内有机酸含量。 相似文献
3.
The oils of the flowers, stems and leaves of Astrodaucus orientalis L. were separately extracted using hydrodistillation (HD), head-space solid-phase microextraction (HS-SPME) and microwave assisted head-space solid-phase microextraction (MA-HS-SPME). The volatile constituents were analyzed by GC and GC/MS. Temperature and time of extraction, microwave power and exposure time of extraction were optimized. Polydimethylsiloxane (PDMS) fiber was used as the solid phase for SPME methods. The main constituents of the flower, stem and leaf oils isolated by HD, HS-SPME and MA-HS-SPME are as follows, respectively: beta-pinene (20.5%, 13.9% and 30.4%), alpha-thujene (8.7%, 16.2% and 10.9%) and alpha-pinene (7.6%, 14.3% and 10.9%) for the flowers, sabinene (11.8%, 32.3% and 11.8%), alpha-pinene (8.7%, 28.8% and 6.1%) and p-mycrene (2.5%, 12% and 8.5%) for the stem, and alpha-pinene (9.4%, 37.1% and 22.5%), sabinene (13.5%, 26.3% and 23.5%), beta-pinene (6.3%, 9.8% and 10%) and p-mycrene (3.2%, 2.5% and 15.6%) for the leaf. The minimum inhibitory concentrations (MIC) were determined for all essential oils obtained by HD against both Gram-positive (Bacillus subtilis) and Gram-negative (Escherichia coli) bacteria using the agar dilution method. These oils showed the good activities against the both bacteria (0.5 - 1.5 mg/mL). 相似文献
4.
The hydrodistilled essential oils of Ocimum basilicum L. cvs. 'Vikarsudha' and 'CIM-Soumya', Ocimum sanctum L. cvs. 'Green' (CIM-Ayu) and 'Purple', Ocimum gratissimum L. and Ocimum kilimandscharicum Guerke have been studied by capillary gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Phenylpropanoids (65.2-77.6%) constituted the major proportion of the essential oil compositions of O. sanctum, O. basilicum and O. gratissimum, whilst oxygenated monoterpenes (72.7%) constituted the major proportion of the oil composition of O. kilimandscharicum. The essential oil compositions of cvs. 'Green' and 'Purple' of O. sanctum were almost the same, and both cultivars were dominated by eugenol (67.4% and 72.8%), β-elemene (11.0% and 10.9%), β-caryophyllene (7.3% and 8.4%) and germacrene D (2.4% and 2.2%), whilst the major components in O. basilicum cvs. 'Vikarsudha' and 'CIM-Soumya' were methyl chavicol (68.0% and 64.9%) and linalool (21.9% and 25.6%), along with bicyclogermacrene (2.0% and 0.7%) and α-terpineol (1.2% and 0.1%). Eugenol (77.2%), 1,8-cineole (7.6%), germacrene D (2.7%) and β-caryophyllene (1.7%) were identified as the major constituents of O. gratissimum. On the contrary, the essential oil from O. kilimandscharicum was mainly dominated by monoterpenoids (95.8%), represented by camphor (64.9%), limonene (8.7%), camphene (6.4%) and (E)-β-ocimene (3.0%). 相似文献
5.
A new element tracer technique has firstly been established to estimate the contributions of mineral aerosols from both inside and outside Beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside Beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in Beijing, of which mineral aerosol accounted for 32%―67% of total suspended particles (TSP), 10%―70% of fine particles (PM2.5), and as high as 74% and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside Beijing contributed 62% (38%―86%) of the total mineral aerosols in TSP, 69% (52%―90%) in PM10, and 76% (59%―93%) in PM2.5 in spring, and 69% (52%―83%), 79% (52%―93%), and 45% (7%―79%) in TSP, PM10, and PM2.5, respectively, in winter, while only ~20% in summer and autumn. The sources from outside Beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in Beijing. The contributions from outside Beijing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors. 相似文献
6.
紫外可见分光光度法测定不同产地龙牙百合中皂苷含量 总被引:2,自引:0,他引:2
为建立龙牙百合总皂苷的测定方法,并确定不同产地龙牙百合中皂苷的含量,以便控制龙牙百合药材的质量,采用香草醛-高氯酸显色,在535 nm处,利用紫外可见分光光度法测定了10个批次的龙牙百合中总皂苷的含量.结果表明,10个不同产地龙牙百合中皂苷的含量,分别是:8.39%、8.11%、8.24%、7.62%、7.38%、9.... 相似文献
7.
CPA矩阵法测定肺保三效片中六组分含量 总被引:1,自引:0,他引:1
本文采用CPA矩阵法测定肺保三效片中六种组分的含量.计算程序采用BASIC语言编制.扑热息痛、苯妥英钠、咖啡因、茶碱、扑尔敏和盐酸麻黄碱的平均回收率和相对标准偏差分别为96.15%,0.77%;96.15%,0.72%;96.41%,0.61%;96.22%,0.71%;96.13%,0.74%;96.16%,0.77%.结果较满意. 相似文献
8.
Dagmar Blazejak-Ditges und Hans Klingeleers 《Fresenius' Journal of Analytical Chemistry》1969,248(1-2):18-20
Zusammenfassung Das photometrische Verfahren von Ploum [1,2] zur Antimonbestimmung mit Jodid in nichtlegierten Stählen wurde so modifiziert, daß einerseits die Arbeitszeit durch Vereinfachung der Methode herabgesetzt wird und es andererseits zur Untersuchung hochlegierter Stähle herangezogen werden kann. 20% Cr, 12% Ni, 3% Mo, 4% W, 2% Mn, 3% V, 1% Ti, 0,4% Si, 0,8% Nb, 0,04% Ta, 0,1% Co, 0,05% Al, 0,05% As, 0,014% Sn und 0,004% B haben keinen Einfluß. Cu > 0,2% stört. Es können Antimongehalte von 0,001–0,025% bestimmt werden.
Direct photometric determination of antimony in alloy steels with iodide
The method of Ploum [1,2] for the direct determination of antimony in plain steels has been modified. It has been possible to reduce the working time in simplifying the method and to apply the procedure to the investigation of high-alloy steels. 20% Cr, 12% Ni, 3% Mo, 4% W, 2% Mn, 3% V, 1% Ti, 0.4% Si, 0.8% Nb, 0.04% Ta, 0.1% Co, 0.05% Al, 0.05% As, 0.014% Sn and 0.004% B have no effect. Cu >0.2% interferes. Sb contents from 0.001 to 0.025% can be determined.相似文献
9.
Luana Riccobono Sergio Rosselli Vincenzo Ilardi Felice Senatore Maurizio Bruno 《Natural product research》2016,30(1):25-34
The chemical compositions of the essential oil and of the non-polar extracts (petroleum ether, dichloromethane) of the aerial parts (flowers, leaves and stems) of Salvia argentea L. were determined by GC-FID and gas chromatography–mass spectrometry analysis. 14-Hydroxy-α-humulene (40.1%) was recognised as the main constituents of the essential oil of S. argentea, together with 1,3,8-p-menthatriene (12.1%), globulol (7.4%) and β-sesquiphellandrene (5.8%). Tritriacontane (9.9% and 14.1%), heptacosane (8.4% and 10.5%), hentriacontane (8.3% and 10.9%), tetradecanal (8.4% and 10.2%) and methyldotriacontane (7.9% and 7.6%) were recognised as the main constituents of the extracts in petroleum ether and dichloromethane, respectively, whereas methyl linolenate (36.6% and 13.5%) and methyl myristoleate (10.5% and 18.5%) were recognised as the main constituents of the methylated extracts. 相似文献
10.
Nawroz Abdul-Razzak Tahir Hoshyar Abdullah Azeez Kadhm Abdullah Muhammad Shewa Anwer Faqe Dlshad Ali Omer 《Natural product research》2019,33(10):1504-1508
The chemical profile of the essential oil of callus and cell suspension cultures derivatives from stem and root of Hypericum triquetrifolium were explored by ITEX/GC-MS. The major constituents for stem derivatives were undecane (78.44%) and 2,4,6-trimethyl-octane (9.74%) for fresh calli, 2,4-dimethyl-benzaldehyde (46.94%), 2,3-dimethyl-undecane (28.39%), 2,4-dimethyl-1-hexene (10.17%), 1,2-oxolinalool (3.64%) and limonene (3.55%) for dry calli and undecane (61.24%), octane, 2,4,6-trimethyl- (16.73%), nonane, 3-methyl-(3.74%), 2,5-diphenyl-benzoquinone (3.70%) and limonene (3.60%) for cell suspension. However, for root derivatives, the dominated components were: undecane (49.94%), eucalyptol (12.07%), limonene (9.98%), toluene (9.03%) and 3-methyl-nonane (4.29%) for fresh calli, 2,4-dimethyl-benzaldehyde (29.80%), 1,1-dimethylethyl-cyclohexane (14.99%), 3-methyl-pentanal (14.99%), undecane (10.04%), beta-terpinyl acetate (8.60%), 1,2-oxolinalool (6.27%) and 2-pentyl-furan (4.09%) for dry calli, undecane (52.38%), 2,4,6-trimethyl-octane (13.81%), 3-methyl-nonane (5.73%), toluene (4.82%) and limonene (4.57%) for cell suspension derivative in root. The attained outcomes indicated that the alkane, aldehyde and monoterpene fractions dominated the chemical composition of essential oils. 相似文献
11.
The chemical composition of the essential oils of the flowers and leaves of Anthemis hyalina were analyzed by GC and GC-MS for the first time. The oils were found to contain seventy-two components. cis-Chrysanthenyl acetate (14.9% and 17.8%), camphor (11.6% and 1.7%), terpinen-4-ol (8.3% and 1.2%), germacrene-D (5.1% and
2.1%), β-caryophyllene (4.1% and 5.4%), myrcene (3.6% and 16.9%), bicyclogermacrene (3.5% and 0.9%), α-pinene (2.3% and 4.1%), cis-β-ocimene (2.1% and 4.3%) and isospathulenol (0.4% and 4.3%) were found to be the major constituents of the oils of flowers
and leaves respectively.
Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 428–429, September–October, 2006. 相似文献
12.
The chemical constituents from the flower, leaf and stem of Helichrysum armenium DC. (Asteraceae) growing in Iran were obtained by hydrodistillation and analyzed by GC and GC/MS. The oil of flower was characterized by higher amount of limonene (21.2%), alpha-cadinol (18.2%), borneol (11.9%), delta-cadinene (9.0%), bornyl acetate (8.0%) and alpha-humulene (7.3%). Twenty one constituents representing 96.2% of the chromatographical leaf oil were identified of which limonene (29.2%), alpha-pinene (14.4%), caryophyllene oxide (6.5%), alpha-gurjunene (6.3%), bornyl acetate (5.5%) and torreyol (5.2%) were the major components. The main components of the stem oil were limonene (23.6%), alpha-pinene (13.4%), spathulenol (6.4%), alpha-gurjunene (6.3%), caryophyllene oxide (5.3%), bornyl acetate (5.2%), beta-cubebene (4.8%) and delta-cadinene (4.3%). The composition of the oils is different, although the most abundant components are identical in leaf oil (96.2%). The antimicrobial effect of flower, leaf and stem essential oils from Helichrysum armenium was studied according to the agar diffusion cup method. The essential oils had a moderate effect on the Gram-positive and Gram-negative bacteria and had a substantial fungicidal effect on the fungi under study. 相似文献
13.
ICP-AES法测定锌阳极中的铝、镉、铁、铜、铅 总被引:2,自引:0,他引:2
通过分析高频功率、雾化压力、辅助气流量和泵速等试验条件,建立了ICP-AES法测定锌阳极中铝、镉、铁、铜、铅的方法。用该方法测定锌阳极中的铝、镉、铁、铜、铅,其RSD分别为0.17%、0.63%、2.7%、5.2%、2.5%,回收率分别为99.3%-101.2%,99.3%-100.3%、97.1%-102.2%、97.8%-102.9%。对锌阳极试样进行测定,该方法的测定结果与GB4951-85方法的测定结果基本一致。 相似文献
14.
采用硝酸、高氯酸进行消解,用ICP-AES对秦艽中的宏量和微量元素含量进行了测定,比较了不同施肥处理与不同生长年限处理对植株内宏量和微量元素的影响.结果表明,不同施肥及生长年限处理秦艽所含宏量和微量元素含量不同,不同施肥处理与CK相比,施NPK混合肥最好,能够增加Fe、Mn、zn、Na、Mg的含量,分别为18.5%、1... 相似文献
15.
The volatile oil compositions of Thymus pannonicus All. from nineteen different localities of Hungary were analyzed by GC/MS. The essential oil content of the Hungarian thyme samples varied between very low (0.14 mL/100 g DW) and fairly high (1.9 mL/100 g DW) values. Significant essential oil polymorphism was found: altogether twelve chemovarieties may have been determined, representing a way of adaptation to different habitat conditions. The main volatile compound of chemotype 1 was thymol (24.6-67.5%), while in the case of chemotype 2, thymol (36.5-63.7%) and p-cymene (11.5-27.3%) predominated. Thymol (28.4-63.7%), p-cymene (11.5-31.8%) and gamma-terpinene (9.7-20.9%) were identified as the chief monoterpenes of chemotype 3, while chemotype 4 contained thymol (36.5%), p-cymene (27.3%) and neral (11.2%). Chemotype 5 accumulated thymol (38.5%), p-cymene (20.6%), gamma-terpinene (12.0%) and beta-bisabolene (10.3%) as its main volatiles. The oil of chemotype 6 can be characterized by thymol (41.9%), p-cymene (20.2%), isoborneol (10.3%) and gamma-terpinene (9.9%), while that of chemotype 7 consisted of thymol (27.7%), linalyl acetate (18.8%), gamma-terpinene (18.6%) and alpha-cubebene (13.9%). In the oil of chemotype 8, p-cymene (45.0%), geraniol (13.6%) and linalyl acetate (9.9%) were found in higher percentages, while chemotype 9 mainly produced linalyl acetate (36.2%) and geranyl acetate (20.2%). Chemotype 10 accumulated germacrene-D (43.4) and beta-caryophyllene (15.0%), while the oil of chemotype 11 contained caryophyllene oxide (45.2%), alpha-cubebene (15.7%) and linalool (13.8%) in high proportions. Germacrene-D (29.7%), beta-caryophyllene (22.0%) and farnesol (10.4%) were identified as main essential oil compounds of chemotype 12. The last nine chemotypes were new for the literature, while the first seven contained thymol as their chief compound. The role of certain sesquiterpenes was found to be considerable. 相似文献
16.
采用王水消解样品,利用原子吸收分光光度法,对重金属元素(Cu、Pb、Zn、Cd)在成都市东郊土壤中的垂直分布进行了研究。该法对Cu的回收率为98%~104%,精密度为2.75%;Pb的回收率为95~97%,精密度为3.11%;Zn的回收率为99%~101%,精密度为2.31%;Cd的回收率为97%~102%,精密度为3.32%,测定方法简单、准确。 相似文献
17.
价电子能级连接性指数及其应用 总被引:46,自引:2,他引:44
价电子能级连接性指数( fE)被定义为: fE=Σ(mi·mj…)-0.5,m为价电子能级值。其中0、1阶指数公式分别为: 0E=Σ(mi)-0.5、 1E=Σ(mi·mj)-0.5。 0E、 1E与化合物的总键能(ΔE)、晶格能(U)、标准生成焓(ΔfH?m)以及非金属氢化物的pKa呈现高度相关性。它们的线性回归方程为:ΔE=-48.0095+1402.94631E,r=0.9474, U=-328.0770+1541.9351 1E, r=0.9801,-ΔfH?m=-266.9299+1324.6461 1E, r=0.9509, pKa=-20.9723+28.1756 1E, r=0.98884, pKa=-14.6102-7.835 0E+40.6461 1E, R=0.9933。m、fE具有物理意义明确、计算方法简单等优点,而且预测结果令人满意。 相似文献
18.
Ho CL Wang EI Tseng YH Liao PC Lin CN Chou JC Su YC 《Natural product communications》2010,5(11):1823-1828
The hydrodistilled essential oils of the leaves and twigs of Litsea mushaensis and L. linii were analyzed. Sixty-nine and ninety compounds were identified in the leaf and twig oils, respectively, of L. mushaensis. The main components of the leaf oil were beta-eudesmol (24.2%), tau-cadinol (10.2%), alpha-humulene (10.1%), alpha-pinene (9.7%), and trans-beta-ocimene (6.5%), whereas the main components of the twig oil were trans-beta-ocimene (19.5%), alpha-pinene (12.8%) and cis-beta-ocimene (7.7%). With L. linii, 72 and 78 compounds were respectively identified in the leaf and twig oils. The main components of the leaf oil were beta-selinene (15.7%), alpha-selinene (15.5%), beta-caryophyllene (12.2%), alpha-humulene (7.2%), and delta-cadinene (5.6%), and of the twig oil trans-beta-ocimene (20.8%), beta-selinene (11.4%), alpha-cadinol (6.0%), delta-cadinene (5.8%), tau-cadinol (5.4%) and beta-eudesmol (5.2%). L. mushaensis leaf oil was shown to have excellent antimicrobial and anti-wood-decay fungal activity, superior to the other oils. 相似文献
19.
The volatile constituents from flower, leaf and stem of Gypsophila bicolor growing in Iran were obtained by hydrodistillation and analyzed by GC and GC/MS. The flower oil was characterized by high amounts of germacrene-D (21.2%), p-cymene (20.6%), bicyclogermacrene (17.6%), gamma-dodecadienolactone (13.7%) and terpinolene (9.4%). Twenty-four constituents representing 97.4% of the leaf oil were identified of which germacrene-D (23.4%), terpinolene (14.5%), bicyclogermacrene (7.5%), gamma-dodecadienolactone (6.8%), p-cymene (6.7%) and cis-beta-ocimene (6.3%) were major components. The main components of the stem oil were gamma-dodecadienolactone (28.5%), bicyclogermacrene (14.8%), germacrene-D (12.6%), p-cymene (12.5%), terpinolene (11.6%) and trans-beta-ocimene (4.2%). The antimicrobial effects of flower, leaf and stem essential oils from Gypsophila bicolor were studied according to the agar diffusion cup method. The essential oils had a moderate effect on the Gram-positive and Gram-negative bacteria, but had a substantial effect on the fungi studied. 相似文献
20.
为了探究丙酮与乙酸乙酯对生物油储存特性的影响,将不同质量分数(3%、6%、9%、12%、15%)的丙酮和乙酸乙酯分别加入到生物油中,考察各组生物油理化特性随储存时间的变化。结果表明,添加丙酮和乙酸乙酯降低了生物油的含水率,且乙酸乙酯对生物油水分的降低效果优于丙酮。储存35 d后,15%乙酸乙酯组生物油的含水率为13.41%,比空白组(16.32%)降低了17.8%。加入添加剂后各组生物油的运动黏度均显著下降,与乙酸乙酯相比,丙酮对运动黏度影响较大。随着添加剂添加比例的增加,生物油运动黏度降低。储存35 d后,添加丙酮质量分数为3%、6%、9%、12%、15%的实验组生物油的运动黏度比空白组分别降低了37.20%、57.78%、71.92%、79.79%、84.67%。两种添加剂均能使生物油的pH值略微增大。红外光谱分析和气相色谱质谱联用分析显示,丙酮和乙酸乙酯抑制了生物油的老化反应。 相似文献