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1.
食物中可溶性铁和可吸收铁的测定   总被引:1,自引:0,他引:1  
为了评价食物中可被吸收利用的铁的量,采用体外法模拟人体胃肠道的消化吸收,考查了八种不同食物的可溶性铁、可吸收铁和铁的可利用率、铁的可吸收率,它们分别在0.006×10-3~0.176×10-3、0.24×10-6~3.09×10-6、4.08%~38.46%和0.11%~1.66%之间。发现摄食相同重量的黑木耳、紫菜或空心菜,可以获得比猪肝或菠菜更多的可吸收铁;就可吸收率而言,蔬菜类食物高于豆制品类食物,富含动物蛋白的食物高于它含植物蛋白的食物。  相似文献   

2.
刘东方  李文昱  康新 《化学教育》2022,43(17):53-61
以“探秘铁肥的合理使用”为主题,开展高中化学“铁及其化合物”的项目式教学。通过完成“确定铁肥的主要成分”“检验铁肥是否变质”“铁肥的合理使用”等3个任务,学生学会不同价态铁元素化合物的转化和检验方法,形成从元素价态和物质类别角度探究物质性质的思路。初步培养了实验探究能力,提升创新意识,发展基于“铁及其化合物价类二维模型建构”的模型认知素养。学生收获了真实新颖、亲身实践、分组合作、交流展示等成就性体验,制作的铁肥保存和合理使用说明书体现了项目式教学的本质特征,实现学习结果的可视性、共享性、交流性。  相似文献   

3.
用蔗糖铁络合物配伍太阳神鸡蛇提取液(生物健)、维生素C等制作蔗糖铁口服液;用低铁料造成大鼠贫血模型(Hb由110g/L下降到60±4g/L)并将动物分为四组,A组继续喂低铁料,B、C、D组在低铁料基础上分别加8×10-6、16×10-6、32×10-6元素铁(来自蔗糖铁口服液).28天后断头取血测Hb、血清铁、肝脏铁.结果表明实验组血清铁、肝脏铁均比A组高,血红蛋白A组继续下降至33.9±12.0g/L,而B、C、D组则分别为55.4±12.8、92.0±8.0、110.0±6.0g/L,本研究提示蔗糖铁口服液具有良好的抗贫血作用.  相似文献   

4.
显色剂5—溴水杨基荧光酮与铁(Ⅲ)的显色反应的研究   总被引:4,自引:0,他引:4  
本文研究了新显色剂5-溴水杨基荧光酮(5-BSAF)与铁(Ⅲ)的显色反应。在pH5.0~6.0HAc-NaAc缓冲介质中,铁(Ⅲ)与5-BSAF、CTMAB形成稳定的三元络合物,其吸收峰为585nm,摩尔吸光系数为1.53×10~5L·mol~(-1)·cm~(-1)。铁浓度在0~8μg/25ml间服从比尔定律。用此法测定了饮料、葡萄酒等样品中微量铁,结果令人满意。  相似文献   

5.
为了解儿童铁营养状况,取微量末梢血,用火焰原子吸收分光光度法测定了2 134例儿童全血铁。结果表明,0~岁组全血铁水平最低,为5.61 mmol/L;8~岁组最高,达6.12 mmol/L;儿童铁缺乏率具有显著年龄趋势,0~岁组铁缺乏率达88.2%,8~岁组降至55.0%。提示儿童特别是婴儿幼儿铁营养状况严重不良。  相似文献   

6.
铁强化酱油与补铁工程   总被引:1,自引:0,他引:1  
仇国苏 《化学教育》2006,27(7):4-4,26
酱油铁强化是国家营养改善项目的一部分,旨在改善我国人口铁营养缺乏状况和控制缺铁性贫血。质量稳定、可接受性好的EDTA铁钠强化酱油,已进入推广应用阶段。其中EDTA铁钠是一种新型食品添加剂和铁的强化剂,本文介绍了其结构、理化性质及生物利用率等,指出了推行铁强化酱油对改善国家公众营养、增进国民健康的意义。  相似文献   

7.
微量铁的测定方法已有许多报道,其中较为理想的分析方法是邻二氮菲比色法和磺基水杨酸比色法。近年来,随着测试技术的提高和新试剂的应用,测铁的灵敏度在不断提高。如荧光熄灭法和催化吸光光度法。其检出限可达2×10~(-8)g·ml~(-1)。但这些方法条件苛刻且测定的线性范围窄。Seitz等利用Fe(Ⅲ)催化鲁米诺-过氧化氢的化学发光反应,测铁的灵敏度已达2×10~(-10)g·ml~(-1)。但该方法中,除Fe(Ⅲ)外,其它金属离子共存时同样有催化作用,干扰大。因而事先大多需要分离。本文对鲁米诺-六氰合铁(Ⅱ)酸钾-铁(Ⅱ)化学发光反应体系的研究,发现在碱性介质中痕量Fe(Ⅲ)对鲁米诺-六氰合铁(Ⅱ)酸钾的化学发光反应有很强的催化作用,且发光强度与Fe(Ⅲ)浓度在较宽范围内呈良好的线性关系。由此建立了一个灵敏度高、选择性好、操作简便、快速,对共存金属离子无需分离的测铁新方法。此法应用于大米、乳粉及水样中铁量测定,结果与邻二氮菲比色法测定结果一致。  相似文献   

8.
吸光光度法测定饮用水中总铁的改进   总被引:4,自引:1,他引:4  
总铁是饮用水中常见的必测的几种基本元素之一,包括总铁在内的诸多元素的测定在国内外均倍受重视,所谓总铁是指饮用水中所含的可溶性铁、悬浮物吸附铁、生物体中铁以及高铁和低铁的总称。国外一般更重视悬浮物铁的测定,而国内大都只对总铁进行测定。本文应用邻菲罗啉(1,10-phenanthroline)吸光光度法,对北京、上海和广州三大城市的150个饮用水样中总铁进行了测定,发现铁在水体中以溶解态、胶体态、悬浮颗粒等形式存在,由于地区及水质的不同,对其测定结果会出现一定的差异,为此,在试剂空白,取样方法及水样用量方面做了必要的研究,从而提高了方法的精度,取得了满意的结果。  相似文献   

9.
铁-锡多核金属有机化合物;二茂铁羧酸;铁-锡多核金属有机化合物的合成及表征  相似文献   

10.
铁氰化钐修饰电极的制备、表征及电催化   总被引:2,自引:0,他引:2  
吴萍  蔡称心  陆天虹 《应用化学》2004,21(11):1101-0
铁氰化钐修饰电极的制备、表征及电催化;铁氰化钐;多巴胺;化学修饰电极;电催化  相似文献   

11.
An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.  相似文献   

12.
An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6ag and imidazo[1,5-a]quinoxalines 7ah by the reaction of 2-imidazolyl anilines 4ac with aryl aldehydes 5ak under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4ab was found to be instrumental for the success of the reaction.  相似文献   

13.
The Diels-Alder reactivity of 1,2-heteroborines (H4C4B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.  相似文献   

14.
A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd2(dba)3-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring.  相似文献   

15.
Both substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles have been synthesized by the 3+2 intramolecular dipolar cycloaddition of nitrilimines to alkynes. This cyclization has been extended to more versatile 3-bromo derivatives by the use of alkynylbromides as dipolarophiles.  相似文献   

16.
An efficient and benign method for the preparation of aminomethyl-substituted fullerenes has been developed. The process, involving catalyst free, visible-light irradiation of 10% EtOH-toluene solutions containing fullerene C60 and N-trimethylsilylmethyl-substituted amines by using a 20 W compact fluorescent lamp, leads to formation of aminomethyl-substituted fullerene adducts in a highly efficient manner. The photoaddition reaction takes place via a pathway initiated by visible light absorption by C60, followed by SET from the amine to the triplet excited state of C60. Ethanol-promoted desilylation of the resulting a minimum radical then generates the corresponding α-amino radical which couples with the C60 radical anion to form the anion precursor of the fullerene adducts. The new approach using visible-light takes place under mild conditions and it does not require the use of photocatalysts. Thus, the method developed in this effort could broadens the range of functionalized fullerene derivatives that can be readily prepared.  相似文献   

17.
The reactions of various nitrones with indolyl- and pyrrolylacrylates proceeds regioselectively with high diastereoselectivity in the case of aldonitrones, and represents an effective method for obtaining new indolyl- and pyrrolyl-substituted isoxazolidine carboxylates stabilized by weak (CH?O) and moderate (NH?N) strength intramolecular hydrogen bonding. The resulting cycloadducts exhibit promising in vitro anti-influenza activities.  相似文献   

18.
A transition metal-free method for the direct amination of benzoxazoles using formamides as nitrogen sources is reported, which was mediated by an inexpensive and environmentally friendly tetrabutylammonium iodide/tert-butyl hydroperoxide system and gave the 2-aminobenzoxazole derivatives with moderate to good yields.  相似文献   

19.
Multifunctionalized 1,2,3,4-tetrahydropyridines are concisely synthesized in good yields via l-proline-catalyzed or l-proline/FeCl3-cocatalyzed one-pot multicomponent reactions (MCRs). The MCRs involve a domino hydroamination/prins reaction/Mannich-type reaction/intramolecular dehydration-cyclization process. The molecular structure of 5baa, one of multifunctionalized 1,2,3,4-tetrahydropyridines, was confirmed by single-crystal X-ray diffraction.  相似文献   

20.
An efficient four-component reaction was developed to take advantage of the reactivity of the 2-aminothiophene-3-carbonitrile functionality, which is obtained during the classical three-component Gewald reaction. Various α-methylene bearing ketones were reacted with malononitrile, elemental sulfur, and aryl/heteroarylnitrile derivatives in t-BuOH/NaOH to afford 2-arylthieno[2,3-d]pyrimidin-4-amines in high yields. Preliminary studies revealed the photophysical properties of the products and their potential for use as metal sensors.  相似文献   

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