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1.
差异蛋白质组学是指依据蛋白质样品在不同时期、不同组织、不同状态或不同外界条件下表达不同,来筛选、鉴定蛋白质,可以通过对差异蛋白质的分析鉴定研究编码该差异蛋白的基因,扩展对该基因功能的研究,也可以结合功能蛋白质组学研究,发现新的蛋白质,完善已有的蛋白质组数据库.  相似文献   

2.
为探究金属有机骨架材料在指印显现领域的应用,本研究采用预混合迅速滴显的方法,使金属有机骨架材料Tb-BTC直接络合在指印纹线上.使用该材料对渗透性客体中A4纸、黑色卡纸、牛皮纸;非渗透性客体中透明玻璃片、瓷砖上的皮脂指印进行显现,探究了不同配比、不同滴加顺序、不同显现时间的预混合溶液对不同类型、不同遗留时间、不同遗留物...  相似文献   

3.
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   

4.
在不同的酸溶液中加入定量苯胺单体,利用电化学恒压法制备了导电性能优良的聚苯胺薄膜,研究了以不同浓度(0.5、1、1.5、2mol/L)的盐酸、高氯酸和对甲苯磺酸为电解质溶液,苯胺在ITO导电玻璃上的聚合电压和颜色变化,并用FT IR、循环伏安和SEM研究了聚合物的结构及性能。研究表明,在不同酸掺杂下薄膜的颜色依次为黄绿色、绿色、深绿色、天蓝色和深蓝色,这是由于不同掺杂酸对阴离子大小的不同导致其分子链上电荷离域不同,从而使得聚合物的掺杂程度不同而发生不同的红移;随着使用电压的增大,溶液中导电能力增强,聚苯胺薄膜的颜色加深;随着同种酸浓度的增加,质子酸的酸性越强,苯胺的聚合电位就越低。  相似文献   

5.
有机晶体生长方法很多,如溶剂中生长、真空升华、辐照聚合、凝胶中生长等等。同一种材料在不同条件下生长,晶型可能不同,缺陷(包括内部空隙)的多少不同,辐照聚合时聚合的程度也不同,即使是同样条件下生长的晶体,由于局部环境的差异等,所得晶体不但大小外形不同,内部缺陷的多少也不尽相同(因而影响密  相似文献   

6.
在不同的酸溶液中加入定量苯胺单体,利用电化学恒压法制备了导电性能优良的聚苯胺薄膜,研究了以不同浓度(0.5、1、1.5、2mol/L)的盐酸、高氯酸和对甲苯磺酸为电解质溶液,苯胺在ITO导电玻璃上的聚合电压和颜色变化,并用FT IR、循环伏安和SEM研究了聚合物的结构及性能。研究表明,在不同酸掺杂下薄膜的颜色依次为黄绿色、绿色、深绿色、天蓝色和深蓝色,这是由于不同掺杂酸对阴离子大小的不同导致其分子链上电荷离域不同,从而使得聚合物的掺杂程度不同而发生不同的红移;随着使用电压的增大,溶液中导电能力增强,聚苯胺薄膜的颜色加深;随着同种酸浓度的增加,质子酸的酸性越强,苯胺的聚合电位就越低。  相似文献   

7.
模拟土壤在自然酸雨淋洗条件下镉的释放行为,研究了不同酸度、不同酸雨成分、不同流量的酸雨对土样中镉淋出的影响,以及镉在不同碳酸根含量的土样对酸雨淋洗的敏感性。  相似文献   

8.
用PJ-356型动电容静电计直流法,测定了一系列不同固体聚电解质的电导率,其电导率一般在10-8到10-12(欧姆·厘米)-1范围.阐明了分子量不同、温度不同、聚甲基丙烯酸锂、钠、钾离子半径不同及聚电解质侧链长短不同对电导率的影响.  相似文献   

9.
化学彩虹     
许亮亮 《化学教育》2013,34(4):80-81
采用不同溶剂构建异相、多层、不同颜色的化学彩虹,大大加深了学生对相似相溶原理的理解;同时结合学生的奇思妙想,用不同浓度的蔗糖溶液成功构建了同相、多层、不同颜色的化学彩虹,并对2种彩虹的优缺点进行了比较分析,以期培养学生良好的问题意识和创新思维能力。  相似文献   

10.
为了考察水飞蓟全草不同部位的组成特征,采用不同的提取溶剂对水飞蓟的幼草、根、茎、叶、花、种子等不同部位提取后,通过高效液相色谱法(HPLC)进行分析。以Hypersil ODS2色谱柱(250 mm×4.6 mm, 5 μm)为分离柱,以50 mmoL/L磷酸二氢钾溶液和甲醇为流动相,梯度洗脱,检测波长为254 nm。在此条件下,水飞蓟不同部位的样品得到了很好的分离,发现不同部位组成差别很大,得到的组分数从幼草、种子、花、叶、根、茎依次减少。水飞蓟不同部位所含的组分极性有很大差别,不同提取方法得到的样品组成也有较大差别。实验结果可为水飞蓟全草的指纹图谱构建及应用开发提供实验依据。  相似文献   

11.
We report a simple TLC densitometric method for the quantification of hecogenin from the leaves of Agave americana using HPTLC. The method was validated for precision, repeatability and accuracy. The method was found to be precise with RSD of 0.78 (intraday) and 0.82 (interday) for different concentrations of hecogenin. Instrumental precision was 0.42 (% RSD) for hecogenin. The content of hecogenin in different samples was estimated by the proposed method and was found to be in the range of 0.05−0.14% w/w in the samples analysed. Accuracy of the method was checked by conducting recovery study at three different levels for hecogenin and the average percentage recovery was 98.98%, 101.92% and 103.33%, respectively. The TLC densitometric method developed for the quantification of hecogenin was found to be simple, precise, specific, sensitive, accurate and can be used in routine quality control. Revised: 7 and 25 April 2006  相似文献   

12.
《Analytical letters》2012,45(7):1409-1424
ABSTRACT|A direct method with graphite furnace atomic absorption spectrophotometry for determining low lead (Pb) levels in urine was described. The present method was based on wet-ashing digestion, 2-fold concentrated urine, and matrix modification with palladium chloride (PdCl2). The sensitivity (concentration at 0.0044 absorption units) of the proposed method is 0.18 ppb. Results were presented on the degree of accuracy and precision. Accuracy of the proposed method was checked by comparison with the values determined by the extracted method (conventional method). Precision of the proposed method was evaluated by within-run and between-run precision. Both of them were found to be satisfactory. Due to the high sensitivity, the proposed method could be applied to determine urinary Pb concentration in normal populations with no known Pb exposure.

Moreover, the method is simple, fast, and automatic.  相似文献   

13.
A capillary electrophoresis-acid barrage stacking online enrichment method has been established to detect the four isoflavones which are Daidzein, Genistein, Formononetin, and Biochanin A. The proposed method was optimized using a single factor alternative method, and the optimal conditions obtained from the optimization were: the BGE was 25 mM borax and 2 mM β-cyclodextrin, the applied separation voltage was 20 kV, and the detection wavelength was 260 nm. The time ratio of the injection of sample and the injection of acid was 150 s:20 s, and the acid used was 250 mM acetic acid. The sample solvent used was 60% v/v acetonitrile. The established method had the enrichment factor of these four isoflavones at 24.5, 32.0, 29.2, and 33.7, respectively, LOD and LOQ are as low as nanograms per milliliter. Finally, the CE-acid barrage stacking method was successfully applied to the determination of four isoflavones in rat plasma and red clover extract, verifying the applicability and feasibility of the method.  相似文献   

14.
A new method for biochemical oxygen demand (BOD) determination, which combines the series piezoelectric quartz crystal (SPQC) technique with the growth of a microorganism is presented in this paper. This method needs no immobilization of bacteria and is simple and convenient. When a calibration technique was used for BOD analysis, the detection time was 2.5 h at 37°C. There was a good linear relationship between the frequency shift and BOD value in the range 2.2–11 mg/L and the regression equation was ΔF = 64.10 + 11.23[BOD]. The proposed method was compared with the conventional BOD5 method. This method was more rapid than the BOD5 method and the results obtained by the former were in good agreement with those obtained by the latter. The experimental conditions are also discussed in detail.  相似文献   

15.
A method for the determination of hydrophobic pollutants in surface waters was developed. The pretreatment was done with microporous membrane liquid–liquid extraction, the extract was eluted to a sample loop in the large-volume injector valve of the gas chromatograph and the extract was injected on-line to the gas chromatograph. The method was optimised using standard compounds and the linearity, the limits of detection and quantification of the method were studied. The method allowed the determination of hydrophobic pesticides and PAHs at the ng L–1 level. The RSD values for the repeatability of the method varied from 4.2% to 25.6%, being on average 9.5%. Surface water samples from Finnish lakes and rivers were analysed.  相似文献   

16.
《Analytical letters》2012,45(1):104-118
Abstract

In this study a spectrofluorimetric method was developed to determine drug active compound in the tablets for albendazole (ABZ). For this aim, fluorescence spectra of albendazolee drug active compound in various solvents were taken, it was determined that the most suitable solvent was chloroform and excitation (λex) and emission (λem) wavelength in a row was 360 nm and 440 nm in this solvent. Calibration graphics were drawn and shown linear at 0–2.5 mg/l concentration range (R2=0.9993). Albendazole quantity in the andazol tablets was determined from directly calibration graphs and with standard addition method. Results obtained with developed spectrofluorimetric method were compared with standard USP method and it was found no difference between two methods within 95% confidence limits. It was determined that proposed method was easy and highly accuracy method to be able to use in routine albendazole analyze for the quality control.  相似文献   

17.
建立了火焰原子吸收光谱法连续测定铬质引流砂中铁、镁含量的分析方法。试样以碳酸钠-硼酸混合熔剂熔融,以盐酸浸取,在校准溶液中加入重铬酸钾和二氧化硅进行基体匹配,抵消基体影响。对熔剂、熔融温度等进行讨论,确立了最佳分析条件,对样品多次测定,其测定结果与国家标准测定方法测定的结果基本一致,相对标准偏差(RSD,n=11)小于0.3%,加标回收率在98.7%~101%。方法具有操作简便、准确性好、速度快、成本低等特点。  相似文献   

18.
Luteolin, a flavonoid, is reported to occur widely in many medicinal plants. It has been shown to have important biological activities. We report sensitive HPTLC method for the quantification of luteolin from plant material. The method was validated for precision, repeatability and accuracy. The method was found to be precise with RSDs for intraday in the range of 0.77–1.29% and inter–day in the range of 1.02–2.08%. Instrumental precision and repeatability of the method were found to be 0.39 and 0.57 (%CV). Accuracy of the method was checked by recovery study conducted at two different levels and the average percentage recovery was found to be 100.92%. The method was used for quantification of luteolin in three important herbal drugs viz. fruit of Cuminum cyminum, whole plant of Bacopa monnieri, flower of Achillea millefolium. The proposed HPTLC method for the quantification of luteolin was found to be simple, precise, specific, sensitive and accurate and can be used for quality control of raw materials.Revised: 1 October 2003 and 18 February 2004  相似文献   

19.
一种纳米TiO2粉体防团聚的新方法   总被引:2,自引:0,他引:2       下载免费PDF全文
开发了一种新的低成本防团聚方法——泡沫悬浮法。对泡沫悬浮法和共沸蒸馏法的防团聚效果进行了系统比较。结果表明,泡沫悬浮法可以有效抑制煅烧过程中纳米TiO2晶粒的粗化和一次粒径的长大。泡沫悬浮法所得纳米TiO2的粉体还具有团聚粒径小、粒度分布窄以及比表面积大的优点。通过FTIR、TG、DTA和松装密度实验对泡沫悬浮法的防团聚机理进行了研究,提出了纳米TiO2防团聚模型。  相似文献   

20.
高频红外碳硫分析仪测定石膏矿中的三氧化硫   总被引:1,自引:0,他引:1  
利用高频红外碳硫仪对石膏矿中三氧化硫含量的测定进行了研究,取得了较好的结果.方法检出限为0.003 0%.用石膏标准样品(GBW03109a,GBW03110)进行分析,测定值与认定值相符,测定值的相对标准偏差(n=9)在0.32%~0.81%之间.使用石膏标准样品(GBW03111)进行本法与国标硫酸钡重量法做比对试验,测定结果无显著性差异.加标回收率为96.4%~104.0%.  相似文献   

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