邻二氮菲分光光度法测定稻米中的植酸含量

建立了一种邻二氮菲分光光度法测定稻米植酸含量的方法：加入过量Fe3+与植酸生成4∶1PA(Fe)4沉淀，再利用盐酸羟胺将剩余Fe3+还原为Fe2+，以邻二氮菲为显色剂，采用分光光度法定量检测Fe2+，从而实现对稻米植酸含量的检测。对测定体系的pH和反应时间进行优化，分析无机磷酸对植酸含量测定的影响，验证方法的重复性和精确度。结果表明：在溶液pH为2.5、反应时间为30 min条件下，可准确测定的植酸浓度为6.7×10–7~2.5×10–5 mol/L，低浓度和高浓度植酸测定工作曲线的R2均大于0.99；无机磷酸浓度低于2.0×10–5 mol/L时，游离的无机磷酸对植酸检测无影响；对6.7×10–7~2.5×10–5 mol/L的标准样品进行5次平行试验，回收率为93.30%~104.67%，RSD为1.25%~7.34%。利用该方法测定的黄华占、金穗408、Kitaake、日本晴等4个品种的稻米植酸含量分别为5.42、4.72、6.40、5.68 mg/g，RSD为1.23%~7.60%。     

对二甲氨基苯甲醛分光光度法测定水样中的水合肼

在酸性条件下,水样中的肼与对二甲氨基苯甲醛作用,生成对二甲氨基苄连氮,用光度法可测定其中水合肼的含量。并分别对高、低浓度水合肼进行了测定。     

野菊花总黄酮清除自由基的活性

采用邻二氮菲-Fe2+氧化法、邻苯三酚自氧化和ABTS法,分别测定野菊花总黄酮对羟自由基(·OH)、超氧阴离子自由基(O-2·)、ABTS自由基正离子(ABTS+·)的清除率。结果表明,野菊花总黄酮清除·OH、O-2·和ABTS+·的半数有效浓度(EC50值)分别为0.016 mg/mL、0.012 mg/mL、6.95μg/mL,优越于常规抗氧化剂维生素C和柠檬酸,证明野菊花具有良好的还原能力和自由基清除活性。     

邻二氮菲-铁(Ⅲ)测定半胱氨酸

研究了邻二氮菲-Fe3+与半胱氮酸的反应,发现半胱氨酸浓度在1.0×10-5~1.8×10-4mol.L-1范围内其产物吸光度值符合朗伯比耳定律。检测限1.0×10-6mol.L-1,表观摩尔吸光系数7.9×103L.mol-1.cm-1。采用本法测定谷氨酸、赖氨酸、半胱氨酸混合试样中半胱氨酸含量,相对标准偏差≤2%,结果令人满意。     

不同薤白多糖体外对自由基的清除作用

采用二苯代苦味酰肼自由基（DPPH·）法和邻二氮菲-Fe2＋-H2O2体系法,研究薤白粗多糖（cAMP）、半纯多糖（AMP）和2种纯化多糖（AMP-I,AMP-Ⅲ）对自由基的清除作用。结果表明,4种薤白多糖均能清除DPPH·和OH·,并随着质量浓度的增加清除作用增强,其中cAMP的清除作用最强,AMP和较低相对分子质量多糖（AMP—I）的清除率较接近。     

肌注复方氨基比林致过敏死亡1例

肌注复方氨基比林致过敏死亡１例梁秀琼，潘雪梅（广东省化州市人民医院，化州５２５１００）复方氨基比林注射液是临床常用的解热镇痛药之一。以往文献有关该药的不良反应时有报道，但过敏立即致死者尚未见于文献，为引起重视，特作报道。男，２７岁，教师。因头痛发热，...     

蔬菜中铁元素的含量及分布研究

采用邻二氮菲分光光度法直接对荠菜、菠菜、油菜、香菜等几种蔬菜不同部位中铁的含量进行测定。分析结果表明:荠菜中以茎、叶含铁量较高,菠菜中则根部含铁量高,为指导人们合理食用蔬菜进行补铁及开发蔬菜产品提供理论依据。     

奶山羊常见疾病及防治

1．流感和感冒。发病初期可肌肉注射复方氨基比林针剂4-5毫升，每日1-2次，或口服清热解毒中药。若继发脑膜炎，可注射青霉素等抗菌素药物。[第一段]     

红酵母NZ-01虾青素生物学特性的研究

对红酵母虾NZ-01青素(以下简称虾青素)的生物学特性进行研究.分别利用硫氰酸铁法及邻二氮菲Fe氧化法检测虾青素的抗氧化性,并从光、温度、pH值和金属离子方面检测其稳定性.结果表明,虾青素有较强的抗氧化性,自然光照、高温、强酸、强碱会对虾青素的稳定性造成不同程度的破坏,Na+、K+、Ca2+、Li2+对虾青素略有增色效...     

野葛藤地上部分挥发油成分分析和抗氧化活性研究

对茅山地区野葛藤的挥发成分进行了初步分析和抗氧化活性研究,采用水蒸气蒸馏-乙醚萃取法对野葛藤进行提取,用GC/MS对其挥发成分进行初步分析,并用DPPH法、邻二氮菲法和邻苯三酚自氧化法研究了葛藤挥发油清除自由基活性。得出结果:葛藤分离出的153个组分中可鉴定组分64个,其中主要以烷酸和烯酸类化合物为主;且挥发油都具有良好的清除自由基活性。     

铁在寒地早粳花药培养中的效应研究

铁是水稻花培培养基的重要成分.通过对7份寒地早粳组合F1(或品系)花药在不同Fe2 含量培养基上离体培养,发现培养基中的Fe2 的含量对诱导率、绿苗分化率影响较大.结果表明在N6培养基中将Fc2 提高到32～40mg/kg诱导率最大,高于N6培养基(Fe2 含量为5.6mg/kg)1.4倍以上.在此以内随着Fe2 含量的增加诱导率增加,大于此含量诱导率降低,呈单峰曲线分布.分化培养基中Fe2 含量增加到40mg/kg分化率显著降低.但在32～40mg/kgFe2 培养基上诱导出的愈伤组织在MS培养基上的绿苗分化率差异明显,85.7%材料可使绿苗生产率提高到7.8%左右.因此适当提高诱导培养基中Fe2 含量可提高寒地早粳的花培效率.     

Infrared study of the hydroxyl bands in clinoamphiboles

Sharp single peaks in the fundamental and first-overtone bands of the O-H stretching vibration in pure Mg(2)+ and Fe(2)+ amphiboles split into a maximum of four sharp peaks, corresponding to hydroxyl groups linked to 3 Fe, 2 Fe + Mg, 2 Mg + Fe, and 3 Mg, in mixed Fe(2)+-Mg(2)+ amphiboles. Within any one solid-solution series, the frequencies of these peaks can be correlated with the electronegativity of ions in the M(l) and M(3) positions, and differences between series can be correlated with the size of ions in the M(4) position. The O-H vector lies approximately normal to z in the (010) plane. The distribution of Fe(2)+ and Mg(2)+ ions between the (M(1),M(3)) and (M(2)M(4)) positions in the cummingtonite-grunerite series, and between the (M(1),M(3)) and M(2) positions in the tremolite-ferroactinolite series, has also been estimated.     

Bacterial Methanogenesis and Growth from CO2 with Elemental Iron as the Sole Source of Electrons

Previous studies of anaerobic biocorrosion have suggested that microbial sulfur and phosphorus products as well as cathodic hydrogen consumption may accelerate anaerobic metal oxidation. Methanogenic bacteria, which normally use molecular hydrogen (H(2)) and carbon dioxide (CO(2)) to produce methane (CH(4)) and which are major inhabitants of most anaerobic ecosystems, use either pure elemental iron (Fe(0)) or iron in mild steel as a source of electrons in the reduction of CO(2) to CH(4). These bacteria use Fe(0) oxidation for energy generation and growth. The mechanism of Fe(0) oxidation is cathodic depolarization, in which electrons from Fe(0) and H(+) from water produce H(2), which is then released for use by the methanogens; thermodynamic calculations show that significant Fe(0) oxidation will not occur in the absence of H(2) consumption by the methanogens. The data suggest that methanogens can be significant contributors to the corrosion of iron-containing materials in anaerobic environments.     

奥地利Wallersee沉积物-水界面铁锰的循环和迁移特征

对奥地利Wallersee沉积物中铁、锰的分布特征进行了分析，说明Wallersee沉积物中铁的循环比锰微弱，铁氧化物的还原作用受到了溶解氧和锰氧化物的双重控制。输入沉积物中的铁大部分都保存于沉积物中。锰氧化物的还原虽然也受到溶解氧的制约，但其还原作用仍比较激烈，孔隙水中有特征的还原峰，只不过峰位下移，所以铁对环境的敏感程度比锰高，沉积物中的铁具有环境记录意义，而锰不具有环境记录意义。铁氧化物中无定形铁氧化物优先还原，晶体铁氧化物可以向无定形铁氧化物转化，参与各种反应。     

Crystallization of some lunar mafic magmas and generation of rhyolitic liquid

During crystallization of lunar crystalline rocks 10022 and 10024, augite changes in composition almost continuously from titanaugite (Ca(36)Mg(47) Fe, (17) with TiO(2) 3 percent) to a very iron-rich variety (Ca(9)Mg(5)Fe(86)), pigeonite changes from Ca(9)Mg(66)Fe(25) to Ca(1O)Mg(51)Fe(39), and olivine changes (in 10022) from Mg(71)Fe(29) to Mg(41)Fe(59), whereas plagioclase stays as bytownite. These compositional variations, as well as the textural relations, may be explained by rapid crystallization of undercooled magmas. The residual liquids found as mesostasis are rhyolitic, which suggests that fractional crystallization of some lunar mafic magmas can generate rhyolitic magmas. Melting experiments were made on crystalline rocks to determine liquidus temperatures and crystallizing phases.     

产蛋母鸡血浆肝及蛋铁硒含量的研究

将 2 78日龄罗曼蛋鸡随机分成 3组 ,以含 2 5mgFe ,含 0 .2mgSe/kg日粮 (对照组 ) ,5 2 5mgFe,1.2mgSe/kg日粮(试验Ⅰ组 ) ,10 2 5mgFe,2 .2mgSe/kg日粮 (试验Ⅱ组 )饲喂 8周 ,结果表明 ,与对照组比较 ,试验组血浆铁硒含量、蛋黄铁硒含量、蛋白硒含量、肝铁硒含量均有大幅度提高。相关性检验表明 ,日粮铁与血浆铁、蛋黄铁 ,血浆铁与蛋黄铁 ,日粮硒与血浆硒、蛋黄硒及蛋白硒 ,血浆硒与蛋黄硒及蛋白硒 ,均呈强正相关 ,P <0 .0 1。这些结果提示 ,通过高铁高日粮可以大幅度提高蛋中铁硒含量 ,产蛋母鸡是日粮中铁硒向蛋中转运的良好载体     

采油废水中硫酸盐还原菌Fe(VI)杀灭试验

采油所产生的废水中产生的硫酸盐还原菌(SRB)可造成注水系统的腐蚀、结垢和阻塞,严重影响原油的开发与生产。以Fe(VI)作为氧化型杀菌剂杀灭SRB,试验结果表明:Fe(VI)对SRB具有很强的灭菌能力;Fe(VI)投加量C>10 mg/L时就能满足回注水的要求;适宜的接触反应时间为t>10 min;相应地有Ct>100 mg·min·L-1。     

A possible primordial peptide cycle

alpha-Amino acids can undergo peptide formation by activation with carbon monoxide (CO) under hot aqueous conditions in the presence of freshly coprecipitated colloidal (Fe,Ni)S. We now show that CO-driven peptide formation proceeds concomitantly with CO-driven, N-terminal peptide degradation by racemizing N-terminal hydantoin and urea derivatives to alpha-amino acids. This establishes a peptide cycle with closely related anabolic and catabolic segments. The hydantoin derivative is a purin-related heterocycle. The (Fe,Ni)S-dependent urea hydrolysis could have been the evolutionary precursor of the nickelenzyme urease. The results support the theory of a chemoautotrophic origin of life with a CO-driven, (Fe,Ni)S-dependent primordial metabolism.     

Removal of meteoric iron on polar mesospheric clouds

Polar mesospheric clouds are thin layers of nanometer-sized ice particles that occur at altitudes between 82 and 87 kilometers in the high-latitude summer mesosphere. These clouds overlap in altitude with the layer of iron (Fe) atoms that is produced by the ablation of meteoroids entering the atmosphere. Simultaneous observations of the Fe layer and the clouds, made by lidar during midsummer at the South Pole, demonstrate that essentially complete removal of Fe atoms can occur inside the clouds. Laboratory experiments and atmospheric modeling show that this phenomenon is explained by the efficient uptake of Fe on the ice particle surface.     

Topographic and magnetic-sensitive scanning tunneling microscope study of magnetite

The topographic and magnetic surface structure of a natural single crystal of magnetite (Fe(3)0(4)), a common mineral, has been studied from the submicrometer scale down to the atomic scale with a scanning tunneling microscope having nonmagnetic tungsten as well as ferromagnetic iron probe tips. Several different (001) crystal planes were imaged to atomic resolution with both kinds of tips. A selective imaging of the octahedrally coordinated Fe B-sites in the Fe-O planes, and even a selective imaging of the different magnetic ions Fe(2+) and Fe(3+), has been achieved, demonstrating for the first time that magnetic imaging can be realized at the atomic level.