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1.
建立了微波消解-微波等离子体炬原子发射光谱(MPT-AES)法测定啤酒中微量元素。考察了微波前向功率、工作气流量、载气流量等参数,确定了MPT-AES法测定各元素的最佳实验条件。在该条件下铜、锌、铁、锰、硒、锶的检出限分别为7ng.mL-1、46ng.mL-1、13ng.mL-1、8ng.mL-1、1.2ng.mL-1、5.6ng.mL-1。相对标准偏差(RSD)均在0.9%~4.8%之间,线性范围分别为0.1~100μg.mL-1、0.5~100μg.mL-1、0.5~100μg.mL-1、0.1~100μg.mL-1、0.01~10μg.mL-1、0.05~100μg.mL-1,加标回收率均在96%~110%之间。  相似文献   

2.
目的:了解母血、脐血、母乳之间锌、铁、硒含量的相关性。方法:对5 6例正常产妇进行了母血、脐血、母乳锌、铁、硒含量的配对分析。结果:各样本中锌在母乳中的含量比脐血中高,其差异具有显著性,P <0. 0 5 ;锌在脐血中的含量显著高于母血中,P <0 . 0 1 ;铁在脐血中含量明显高于母血,而母血又明显高于母乳,P <0 . 0 1 ;脐血、母血、母乳硒含量依次升高,其间差异不明显;母血与脐血中的锌含量具有明显的相关性(r =0 .478,P <0 .0 1 ) ,铁也具有相似的变化(r=0 . 5 2 2 ,P <0 . 0 1 ) ;母血与母乳中的锌、铁也具有相关性(r =0. 3 5 6) ,P <0 . 0 5 ;r =0. 42 1 ,P <0 . 0 1 )。结论:锌、铁、硒为胎儿生长发育中的重要元素,在母乳中含有大量的锌和硒,故应提倡母乳喂养,但4个月后应添加含铁辅食,补充母乳中铁的不足。  相似文献   

3.
用营养调查方法 ,对门诊 30例血透肾衰患者进行了调查 ,并对其进食中国营养平衡米(下称营养平衡米 )膳中Ca、P、K、Na、Mg进行了论证。临床表现为面黄肌瘦、苍白、浮肿、疲劳、消瘦、虚弱、无力、食欲不振、恶心呕吐、头晕、皮肤瘙痒、肌肉震颤、手足麻木、无精神等明显的营养不良表现 ,平均体重 5 3 5kg ,皮脂厚度 1 1 2cm ,血清总蛋白 6 7 31mg/dL ,白蛋白 37 4 9mg/dL ,RBC 2 4 1× 1 0 12 /L ,HGB 6 8 81g/L ,PLT 1 72 1× 1 0 9/L ,K 1 6 1 5mg/dL ,Na392 72mg/dL ,C1 2 88 2 2mg/dL ,Ca 6 2 8mg/dL ,P 6 1 1mg/dL ;氮质血症 (x) :BUN 31mmol/L ,Cr 1 0 0 2 6 μmol/L ;膳食中平均每人每日常量元素摄入量为Ca34 1 4 3mg、P 70 7 0 9mg、K1 2 1 5 5 6mg、Na 2 2 2 6 1 9mg、Mg 1 79 4 5mg ,以肾衰病人RDA标准为Ca 1 0 0 0 /1 5 0 0 ,P 6 0 0 ,K5 0 0 ,Na 1 0 0 0 ,Mg 2 0 0 /30 0 ,评价分别为 2 3%~ 34 %、 1 1 8%、 2 4 3%、 2 2 3%、 6 0 %~ 90 % ,则K、Na、P过量 ,而Ca、Mg不足。若改食用营养平衡米膳 ,摄入量分别为 1 4 2 3、 92 4、 1 4 32、 2 2 36、2 79mg ,达标率分别为 95 %~ 1 4 2 % ,1 5 4 % ,2 86 % ,2 2 4 % ,93%~ 1 4 9%。则达标率 1 0 0 % ,且比原来膳食中元素平衡。  相似文献   

4.
金属饰品样品用硝酸(20+80)溶液浸泡过夜,采用电感耦合等离子体原子发射光谱法测定金属饰品中铅、镉、铬、汞、锑、砷、硒、钡和镍的溶出量。选择波长为216.9,228.8,267.7,194.2,206.8,189.0,196.0,455.4,216.6nm的9条谱线依次作为测定铅、镉、铬、汞、锑、砷、硒、钡和镍的分析线。铅、镉、铬、锑、砷、硒、钡和镍的质量浓度与其发射强度在10.0mg·L-1以内、汞在2.0mg·L-1以内呈线性关系,检出限(3s)在0.002~0.05mg·L-1之间。方法用于金属饰品的分析,回收率在95.4%~103.0%之间,测定值的相对标准偏差(n=11)在0.68%~2.0%之间。  相似文献   

5.
ICP-AES法测定钛合金中的铝、钒、钼、铁、锆   总被引:6,自引:2,他引:4  
用ICP-AES法测定钛合金中的铝、钒、钼、铁、锆,研究了高频功率、雾化压力、辅助气流量、泵速对待测元素发射谱线强度的影响,优化的测定条件为:高频功率1150W,雾化压力165.7kPa,辅助气流量0.5L/min,泵速100r/rain。该法测定结果的相对标准偏差不大于1.2%,待测元素的回收率为98.0%~101.1%。  相似文献   

6.
原子吸收法测定中草药中钙、镁、铁、锌、铜和锰   总被引:12,自引:0,他引:12  
钙、镁、铁、锌、铜、锰都是人体必不可少的元素 ,而中草药中这些元素的测定 ,无论是从中医药学还是营养卫生学的角度而言 ,都显得极其重要和必不可少[1 ,2 ] 。本文采用原子吸收分光光度法连续测定中草药中的钙、镁、铁、锌、铜、锰。1 实验部分1 .1 仪器与试剂Z 80 0 0偏振塞曼原子吸收分光光度计 ,配火焰和石墨炉原子化器 (日本日立公司 )。LaCl3溶液( 1 0 0g/L) ;SrCl2 溶液 ( 5 0g/L) ;钙、镁、铁、锌、铜、锰混合标准储备液 (Ca、Mg、Fe 2g/L ,Mn 1g/L ,Zn、Cu 0 5g/L)。1 .2 样品液的制备准确称…  相似文献   

7.
采用营养调查方法 ,对门诊 30例血透肾衰患者进行了调查 ,并对其进食中国营养平衡米膳改善Zn、Cu、Fe、Mn、Se不平衡进行了论证。结果表明 ,临床表现为面黄肌瘦 ,苍白 ,浮肿 ,疲劳 ,消瘦 ,虚弱 ,无力 ,食欲不振 ,恶心呕吐 ,头晕 ,皮肤瘙痒 ,肌肉震颤 ,手足麻木 ,无精神等明显的营养不良 ,平均体重 5 3 5kg ,皮脂厚度 1 1 2cm ,检验为血清总蛋白 67 31mg dL ,白蛋白 37 4 9mg dL ,RBC 2 4 1× 1 0 12 /L ;氮质血症 (x) :BUN 31mmol l,Cr 1 0 0 2 6μmol L。膳食中平均每人每日微量元素摄入量为 :Fe 1 7 99mg ,Zn 1 0 35mg ,Se 5 9 2 2 μg,Cu 1 71mg ,Mn3 95mg ,以肾衰患者RDA标准评价 ,Zn、Cu未达到RDA ,Fe ,偏高 ,Mn、Se达标。证明血透肾衰患者微量元素营养不平衡。RDA标准评价分别为 1 5 0 %、 69%、 1 1 8%、 86%、 1 5 8%。若改食中国营养平衡米膳 ,Fe、Zn、Se、Cu、Mn摄入量分别为 1 9 74mg、 2 4 64mg、 1 78mg、4 0 9mg ,达标率分别为 1 65 %、 1 64%、 1 5 7%、 89%、 1 64% ,则全部达标率近 90 %以上 ,且比原来膳食中元素平衡 ,证明营养平衡米膳的Fe、Zn、Se、Cu、Mn均与RDA标准模式平衡。因此 ,建议血透肾衰患者进食中国营养平衡米膳 ,可望改善其微量元素营养不平衡状况 ,提高生存质  相似文献   

8.
ICP-AES法测定铜镍矿、铅锌矿中铜、镍、铅、锌、钴   总被引:9,自引:0,他引:9  
用电感耦合等离子体发射光谱法测定铜镍矿、铅锌矿石中铜、镍、铅、锌、钴,样品用盐酸-硝酸溶解,在选定的测量条件下以ICP—AES测定溶液中的Cu、Ph、zn、Co、Ni的含量.对国家一级标准物质进行测定,方法精密度(RSD,n=12)为Cu 2.92%~6.62%,Pb 1.88%-2.61%,Zn 1.30%-2.05%,Co 6.90%,Ni 2.23%.本方法具有线性范围宽、干扰少、快速、简便、检出限低等优点.用于实际使用,结果满意.  相似文献   

9.
用交流电桥法测定了熔融KCl-NaCl(1:1摩尔)-RECl_3的电导。比电导的温度函数表达式如下: k=A+B(t-700) k:比电导(Ω~(-1)·cm~(-1));t:温度(700—850℃); A、B:本文给出的常数。 讨沦了实验值与计算值的偏差,当稀土氯化物在熔体中的浓度为10—50重量百分数时可能形成了络合物。  相似文献   

10.
火焰原子吸收法测定植物叶片中Pb、Cd、Cu、Zn含量   总被引:11,自引:1,他引:10  
对八种植物叶片 (糖胶树、榕树、红花羊蹄甲、银合欢、垂叶榕、白玉兰、蟛蜞菊、大花紫薇 )中Pb、Cd、Cu、Zn的测定方法进行了研究 ,采用炭化—灰化—硝酸溶解方法进行样品处理 ,火焰原子吸收法测定Pb、Cd、Cu、Zn四种重金属元素。结果表明 ,该法准确 ,回收率高。各元素的回收率分别为 :铅 88%~ 1 0 5 %、镉 90 %~ 1 0 3 %、铜 90 %~ 1 0 5 %、锌 91 %~ 1 0 5 %。  相似文献   

11.
标题化合物C24H30O5是由邻甲氧基苯甲醛与5,5-二甲基-1,3-环己二酮在N,N-二甲基甲酰胺中反应而得。结构通过单晶X-射线衍射法确定,其晶体属于单斜晶系,空间群C2/c,a=33.942(6),b=7273(1),c=22667(4)A,β=128.989(9)°,Mr=398.50,V=4349(1)A3,Dc=1.2179·cm-3,Z=8,μ(MoKa)=840mm-1,F(000)=1712。晶体结构用直接法解出,经用全矩阵最小二乘法对原子参数进行修正,最后的偏离因子为R=0.043,Rw=0.052。在晶体结构中,存在一个分子间氢键。  相似文献   

12.
The synthesis, characterization, structure, and electrochemistry of [1.1]ferrocenophanes, bridged by the heavier group 13 elements aluminum (1a), gallium (1b), and indium (1c), are described and discussed. Compounds 1a-c have been synthesized from dilithioferrocene and intramolecularly coordinated group 13 element dihalides Ar'EX(2) (Ar' = 2-(Me(2)NCH(2))C(6)H(4); EX(2) = AlCl(2), GaCl(2), InI(2)). Although the synthesis and characterization of 1a by single-crystal X-ray analysis has been described recently (Braunschweig, H.; Burschka, C.; Clentsmith, G. K. B.; Kupfer, T.; Radacki, K. Inorg. Chem. 2005, 44, 4906), compounds 1b and 1c are described for the first time. The galla (1b) and the inda (1c) [1.1]ferrocenophane have been characterized by single-crystal X-ray determination [1b: C(38)H(40)Fe(2)Ga(2)N(2), monoclinic, P2(1)/c, a = 10.3467(5) Angstroms, b = 11.6311(4) Angstroms, c = 14.0747(7) Angstroms, beta = 105.931(2) degrees, Z = 2; 1c: C(38)H(40)Fe(2)In(2)N(2), monoclinic, P2(1)/c, a = 10.5522(7) Angstroms, b = 11.8476(8) Angstroms, c = 13.9855(9) Angstroms, beta = 104.990(3) degrees, Z = 2]. All three compounds 1a-c are anti conformers with trans orientations of the two donating NMe(2) groups. For the [1.1]ferrocenophane 1a, an unprecedented fully reversible two-electron redox process was observed by cyclic voltammetry, whereas the corresponding Ga and In species exhibit a more conventional stepwise redox chemistry. According to the Robin-Day classification, 1a is a class I and 1b and 1c are class II species. In addition to the reversible processes, compound 1a shows an irreversible oxidation at higher voltages accompanied by adsorption processes. The irreversible adsorption process was investigated with an electrochemical quartz crystal microbalance (EQCM).  相似文献   

13.
The phase diagram of the ternary surfactant system tetradecyldimethylamine oxide (TDMAO)/HCl/1-hexanol/water shows with increasing cosurfactant concentration an L(1) phase, two L(alpha) phases (a vesicle phase L(alpha1) and a stacked bilayer phase L(alphah)), and an L(3) phase, which are separated by the corresponding two-phase regions L(1)/L(alpha) and L(alpha)/L(3). In this investigation, the system was studied where some of the TDMAO was substituted by the protonated TDMAO. Under these conditions, one finds for constant surfactant concentration of 100 mM TDMAO a micellar L(1) phase, an L(alpha1) phase (consisting of multilamellar vesicles), and an interesting isotropic L(1)(*) phase in the middle of the L(1)/L(alpha) two-phase region. The L(1)(*) phase exists at intermediate degrees of charging of 30-60% and for 40-120 mM TDMAO and 70-140 mM hexanol concentration. At surfactant concentrations less than 80 mM the L(1)(*)-phase borders directly on the L(1) phase. The phase transition between the L(1) phase and the L(1)(*) phase was detected by electric conductivity and rheological measurements. The conductivity values show a sharp drop at the L(1)/L(1)(*) transition, and the zero shear viscosity of the L(1)(*) phase is much lower than in L(1) phase. The form and size of the aggregates in L(1)(*) were detected with FF-TEM and SANS. This phase contains small unilamellar vesicles (SUV) of about 10 nm and some large multilamellar vesicles with diameters up to 500 nm. The system exhibits another peculiarity. For 100 mM surfactant, the clear L(alpha1)-phase exists only at chargings below 30%. With oscillating rheological measurements a parallel development of the storage modulus G' and the loss modulus G" was observed. Both moduli are frequency independent and the system possesses a yield stress. The storage modulus is a magnitude larger than the loss modulus. Copyright 2000 Academic Press.  相似文献   

14.
StudiesonHeteromacrocyclicPolyether(X)SynthesisandStructuralCharacterizationof2,3,11,12-Dibenzo-1,4,10,13-tetraselena-7,16-di...  相似文献   

15.
[reaction: see text] This study is a multinational, multidisciplinary contribution to the thermochemistry of dimethyl1,4-cubanedicarboxylate and the corresponding isomeric, cuneane derivative and provides both structural and thermochemical information regarding the rearrangement of dimethyl 1,4-cubanedicarboxylate to dimethyl 2,6-cuneanedicarboxylate. The enthalpies of formation in the condensed phase at T = 298.15 K of dimethyl 1,4-cubanedicarboxylate (dimethyl pentacyclo[4.2.0.0.(2,5)0.(3,8)0(4,7)]octane-1,4-dicarboxylate) and dimethyl 2,6-cuneanedicarboxylate (dimethyl pentacyclo[3.3.0.0.(2,4)0.(3,7)0(6,8)]octane-2,6-dicarboxylate) have been determined by combustion calorimetry, delta(f) H(o)m (cr)/kJ x mol(-1) = -232.62 +/- 5.84 and -413.02 +/- 5.16, respectively. The enthalpies of sublimation have been evaluated by combining vaporization enthalpies evaluated by correlation-gas chromatography and fusion enthalpies measured by differential scanning calorimetry and adjusted to T = 298.15 K, delta(cr) (g)Hm (298.15 K)/kJ x mol(-1) = 117.2 +/- 3.9 and 106.8 +/- 3.0, respectively. Combination of these two enthalpies resulted in delta(f) H(o)m (g., 298.15 K)/kJ x mol(-1) of -115.4 +/- 7.0 for dimethyl 1,4-cubanedicarboxylate and -306.2 +/- 6.0 for dimethyl 2,6-cuneanedicarboxylate. These measurements, accompanied by quantum chemical calculations, resulted in values of delta(f) Hm (g, 298.15 K) = 613.0 +/- 9.5 kJ x mol(-1) for cubane and 436.4 +/- 8.8 kJ x mol(-1) for cuneane. From these enthalpies of formation, strain enthalpies of 681.0 +/- 9.8 and 504.4 +/- 9.1 kJ x mol(-1) were calculated for cubane and cuneane by means of isodesmic reactions, respectively. Crystals of dimethyl 2,6-cuneanedicarboxylate are disordered; the substitution pattern and structure have been confirmed by determination of the X-ray crystal structure of the corresponding diacid.  相似文献   

16.
2, 5-二取代基-1, 3, 4-恶二唑及恶二唑啉类化合物的合成   总被引:40,自引:0,他引:40  
2-苯基-1,2,3-连三唑-4-甲酰肼(1)与芳酸在POCl~3催化下得到6种新的2-芳基-5-(2'-苯基-1',2',3'-连三唑-4'-基)-1,3,4-恶二唑(2)。1与羰基化合物缩合得到相应的酰腙(3),在Ac~2O作用下环化成2-取代基-3-乙酰基-5-(2'-苯基-1',2',3'-连三唑-4'-基)-1,3,4-恶二唑啉(4)。化合物的结构经元素分析,IR,^1HNMR和MS确证。  相似文献   

17.
The preparation of 25,27-bis[1-(2-ethyl)hexyl]- and 25, 27-bis[1-(2-tert-butoxy)ethyl]calix[4]arene-crown-6 combining one polyether crown-6 and one alkylchain O-attached on each side of a calix[4]arene in the cone, partial-cone, and 1,3-alternate conformations are reported. The control over 25, 27-bisalkylcalix[4]arene-crown-6 conformation via varying specific reaction conditions was studied. The series of calix[4]arenes have been prepared by two routes, which differ in the order in which the alkyl or polyether groups were introduced. Moreover, methods have been developed to selectively prepare the cone and partial-cone conformers by using an appropriate base in the alkylation reactions. The conformations of these new derivatives have been probed by (1)H NMR analysis and X-ray crystallography. The (1)H and (13)C NMR spectra of 25,27-bis[1-(2-ethyl)hexyl]calix[4]arene-crown-6, 1, 3-alternate 1, cone 2, and partial-cone 3 are also discussed.  相似文献   

18.
Heptanuclear metal-centered, six-membered, mixed-valent, heterometallic wheels 1-3 of iron, manganese, and indium were prepared in a one-pot reaction from N-benzyldiethanolamine (H2L(1)), cesium carbonate, [PPh4]2[MnCl4], and FeCl3 or InCl3. All three complexes were characterized by the combination of elemental analysis, FAB mass spectroscopy, X-ray diffraction and cyclic voltammetry and in the case of 1 additionally by M?ssbauer spectroscopy. In 1, four Mn(II) ions in the periphery are arranged in pairs alternating with one Fe(III) ion each, with an Fe(III) ion located in the center. In 2, three Mn(II) ions alternate with three In(III) ions, whereas in 3, four In(III) ions are arranged in pairs and alternate with one Mn(II) ion each. In 2 and 3 an Mn(II) ion is encapsulated in the center.  相似文献   

19.
标题化合物C24H29NO4?1/2C2H5OH稨2O)由香兰素、5,5-二甲基-1,3-环己二酮、醋酸铵在微波辐射下干反应并经95%乙醇重结晶而得C24H29NO4穀2(C2H5OH稨2O)晶体。结构通过单晶X-射线衍射法确定,其晶体属单斜晶系,空间群P21/n, a = 9.810(2), b = 14.516(3), c = 17.008(3) ? b = 101.03(2), V = 2377.2(8) ?, Z = 4, Mr = 427.52, Dc = 1.195 g/cm3 , m(MoKa) = 0.082 mm-1, F(000) = 920。晶体结构用直接法解出,经全矩阵最小二乘法对原子参数进行修正,最终的偏离因子为R = 0.0406, wR = 0.0892。X-射线衍射分析结果表明,吡啶环和与之稠合的2个六员环均为信封式构象。  相似文献   

20.
通过2-甲基-4-对甲苯基-1-苯甲酰基-2,3-二氢-1H-1,5-苯并二氮杂与由不对称1-苯基-2-偶氮-1,3-丁二酮热解产生的a-羰基烯酮的[2+4]环加成反应制备了标题化合物(C34H30N2O3,Mr=514.62),用X射线衍射测定了其单晶结构。晶体属单斜晶系,空间群为P21/n,a=11.560(1),b=19.058(3),c=13.207(2)A,β=106.82(1)°,V=2785.2(7)A3,Z=4,Dc=1.230g.cm-3,MoKa(λ=0.71073A),μ=0.064mm-1,F(000)=1088,2278个可观测衍子射点,R=0.046,Rw=0.049。分子骨架为由苯环、具有类扭船式构象的七元二氮杂环和略微扭曲的唑酮环构成的三环体系。  相似文献   

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