超声雾化和气体发生进样微波诱导等离子体原子发射光谱法测定痕量碘

本文用Ａｒ和ＨｅＭＩＰＡＥＳ测定水溶液中的碘。样品经超声雾化和气体发生后引入等离子体。考查了Ａｒ和ＨｅＭＩＰ中碘的发射光谱特性和一些实验参数对碘发射强度的影响。当用超声雾化引入样品时，用Ａｒ和Ｈｅ作工作气体，检出限分别为０．１２和０．０６μｇ／ｍｌ，当用气体发生引入样品时，用Ａｒ作工作气体，检出限为０．０６４μｇ／ｍｌ，相对标准偏差小于５％。     

气相色谱法测定食盐中无机碘

利用化学反应和气相色谱法测定食盐中无机碘。在强酸介质中,食盐中的无机碘被亚硝酸钠还原成游离碘,游离碘遇丙酮立刻生成碘丙酮,用气相色谱电子捕获检测器测定其含量。气相色谱柱为６％ＤＥＧＳ＋１％Ｈ３ＰＯ４／ＣｈｒｏｍｏｓｏｒｂＷ ＡＷ ＤＭＣＳ填充柱,柱温为８０℃,三溴甲烷为内标物,碘丙酮和三溴甲烷的保留时间分别为４．０ｍｉｎ和１．９ｍｉｎ,样品的平均回收率为１０１．２％,相对标准偏差为１．９％。     

间接原子吸收光谱法测定碘离子

本文建立了一种新的原子吸收光谱法间接测定碘离子。碘离子在一定条件下和硫脲－铜（Ｉ）形成离子对，被甲基异丁基甲酮萃取。在实验建立的最佳条件下，以火陷／石墨炉法测定有机相中铜的原子吸收信号，可以间接求得碘离子合含量。本方法具有线性范围宽，重现性好，环境污染小，简便，快速等特点。地用于甲状腺肿与机能亢进等药物中碘离子的测定，取得满意结果。     

石墨炉T1I分子吸收光谱法测定地质样品中痕量碘

提出以五氧化二钒和 混合助融剂高温热解地质样品，平台石墨炉Ｔ１Ｉ分子吸收光谱法测定地质样品右痕量碘。方法简便，可靠，标准物质测定结果与推荐值吻合。     

碘-四氯化碳萃取光度法间接测定痕量草酸根

本研究了在稀硫酸介质中，一定的反应条件下，碘酸根与草酸根反应，稀释出 一定量的碘，据此建立了碘－四氯化碳萃取光度法间接测定草根的方法。反应温度控制在９０℃，反应时间控制在３ｍｉｎ，反应酸度控制在ｐＨ１．０￣２．０，共顾离子基本不干扰测定，草酸根的最低检测限为０．０８μｇ／ｍＬ，通过方法的回收率试验以及与其他测定方法进行比较得到了满意的结果，回收率在９６￣９８％之间。     

氧化-原子发射光谱快速测定油田水中微量碘

柴达木盆地西部的南翼山地区油田水中碘资源丰富,有极大的开发利用价值。该油田水盐度高,组成复杂,现有碘的分析方法难以满足研究工作的需求,建立准确分析南翼山油田水中碘浓度的方法是开展相关研究工作的基础和关键。电感耦合等离子体原子发射光谱（ICP-AES）具有分析快速、线性范围宽、样品基体影响小等优势。然而,由于碘属于高电离能元素,ICP-AES直接测定碘的灵敏度低、检出限高,不能满足样品中微量碘的分析要求。借助自行设计加工的用于ICP-AES集进样、化学反应和气液分离三种功能为一体的进样装置（其具有组成合理、结构紧凑的优点）,将碘离子氧化为碘单质导入ICP-AES中测定,在提高有效进样量的同时降低了样品基体对碘测定的影响,从而大幅降低了碘的检出限,建立了ICP-AES快速测定油田水中微量碘的方法。优化了氧化碘离子为碘单质所用酸和氧化剂的浓度,最佳反应试剂为10 mmol·L-1 NaNO₂和1 mol·L-1 HNO₃。I 178.276 nm处的检出限为1.65 μg·L-1,一次测定所需时间三分钟。采用部分因子实验设计详细研究了南翼山油田水中主要共存离子（如钾、钠、钙、镁、锂、锶、铵）及它们之间的交互作用对碘分析的影响。在95%置信水平下,发现钙对碘的测定存在显著性影响。通过对样品进行适当的稀释可以消除钙和其他组分对碘准确测定的影响。采用标准曲线法将建立方法应用于南翼山不同蒸发浓缩阶段实际油田水中碘的分析,测定结果表明加标回收率为90%～104%。实验建立的分析方法具有简便快速、基体干扰小、准确度高等优点,为油田水中微量碘的测定提供了一种新的方法,对于卤水碘基础数据的获得和碘分离提取工艺具有重要意义。     

铕的时间分辨激光荧光光谱分析：Ⅰ方法研究

本工作是在自建装置上，利用时间分辨激光荧光光谱技术，选择Ｅｕ－ＴＴＡ－ＥｔＯＨ液体荧光体系，建立了时间分辨激光荧光测定铕的方法。该测定铕离子的线性范围为０．０００２－１０μｇ／ｍｌ检测限为１０＾－５μｇ／ｍｌ。０．０３μｇ／ｍｌＥｕ＾３＋标准样品ＥｕＴＴＡ３，测定的相对标准偏差为４．７％，该法用于实际样品的分析测定，结果满意。结合铕的分析，对本方法选择化学体系的条件、测定装置的参数进行了讨论。并获     

钐的时间分辨激光荧光光谱分析方法研究

本文利用Ｓｍ－ＴＴＡ－ＥｔＯＨ液体荧光体系，采用时间分辨激光荧光检测手段，建立了散的时间分辨光荧光分析法，该法的线性范围为０．０１～１０μｇ／ｍｌ，检出限为３．３ｎｇ／ｍｌ，０．５μｇ／ｍｌ钐标样测定的相对标准差为３．７％（ｎ＝１２），结合混合稀土中多种元素共存的特点，实验确定了装置的有关参数，用标准加入方法对实际样品进行了测定，并与其他方法测定结果进行了比较，结果满意，本法测定实际样品中钐的相对     

电感耦合等离子体发射光谱法测定碘的研究

建立了用ICP AES测定碘的新方法 ,采用PHD氢化物发生器将亚硝酸钠和样品溶液分两路送入雾化器 ,使碘离子氧化为挥发性的碘单质而提高碘的传输效率。解决了过去碘的发射信号随放置时间的增加而变小的问题。同时发现采用亚硝酸钠作氧化剂在低酸度下可消除氯离子的干扰 ,方法的检出限为 14ng·mL-1,精密度为 1 2 % (c=2 μg·mL-1,n =10 )回收率为 99 44 % ,本方法已用于食盐和海水中碘的测定 ,结果令人满意     

双波长分光光度法测定银杏果仁中直链淀粉和支链淀粉

本文研究了以碘为显色剂,应用双波长分光光度法测定银果仁中直链淀粉和支链淀粉的含量。对显色反应和光度测定的最佳条件进行了详细的考察。根据碘－直链淀粉和碘－支链淀粉复合物的吸收光谱,选择直链淀粉的测定波长为５６８ｎｍ和４２０ｎｍ,支链淀粉的测定波长为１５２ｎｍ和６４８ｎｍ,依据回归方程可求出直链淀粉和支链淀粉的含量,直链淀粉的浓度在０－３６μｇ／ｍＬ,支链淀粉在０－１１０μｇ／ｍＬ范围内符合比耳定律,     

N2-苯浮选缔合光度法测定碘的研究

本文依据在强酸性磷酸介质中,Br2氧化I-为I2,进而与I-生成配阴离子I-3,利用溴化十六烷基三甲胺(CTMAB)与I-3发生等离子对缔合物反应,生成缔合物CTMA+*I-3,该缔合物易溶于苯,且在苯中稳定,从而建立了溶剂浮选光度法测碘新方法.本法灵敏度高,选择性强,精密度好,实测了天然水及加碘的盐中碘,结果令人满意.     

ZnS:I单晶降阻条件的选择

本文叙述了对碘化学输运法生长的ZnS:I单晶扩散Al杂质,制备低阻ZnS:I晶体的实验方法。在制备低阻ZnS:I单晶过程中,根据晶体内含I的浓度选择热退火条件,可较重复地得到Al浓度在10-1g/g量级,电阻率在10—102Ω·cm范围的低阻ZnS单晶。讨论认为,在ZnS:I单晶退火过程中,I的存在有助于Al杂质的扩散。     

Experimental study on the system of Cl/Cl_2/He/HN_3/I_2

Using a microwave generator, chlorine diluted by helium was dissociated to chlorine atoms that subsequently reacted with hydrogen azide to produce the excited states of NCl(a1△). Meanwhile, molecular iodine with carrier gas of helium reacted with atomic chlorine to produce atomic iodine which then was pumped to excited state of I(2P1/2) by an energy transfer reaction from NCl(a1△). In this paper, the changes of NCl(a1△) and NCl(b1∑) emission intensity is presented when I2/He is introduced into the stream of Cl/Cl2/He/HN3/NCl(a1△)/NCl(b1∑). The dependences of atomic iodine I(2P1/2) on flow rates of gases were also investigated. The optimum parameters for I(2P1/2) production are given.     

Possibility of separating the isotopes127I and129I with the aid of a photodissociation iodine laser

A method for separating iodine isotopes is proposed, based on the large difference between the rate constants of the excited I*(²P_1/2) and unaxclted iodine atoms with radicals CF₃ and with Cl₂ molecules, and on the possibility of selectively acting on the₁₂₇I atoms in the states²P_1/2 and²P_3/2 by radiation from a photodissociation R¹²⁷I iodine laser (λ = 1.315 μm). The possibility of separating the pure isotope¹²⁹I and the mixture¹²⁷I with¹²⁹I is investigated.     

Anomalous bond-length behaviors of solid halogens under pressure

The three halogen solids(Cl_2, Br_2, and I_2) have the isostructural diatomic molecular phase I with a space group of Cmca at ambient pressure. At high pressure, they all go through an intermediate phase V with incommensurate structures before eventually dissociating into the monatomic phase II. However, a new structural transition between phase I and V with anomalous bond-length behavior was observed in bromine under pressure, which, so far, has not been confirmed in iodine and chlorine. Here, we perform first-principles calculations for iodine and chlorine. The new structural transition was predicted to be common to all three halogens under pressure. The transition pressures might be systematically underestimated by the imperfect van der Waals correction method, but they follow the order Cl_2 Br_2 I_2, which is consistent with other pressure-induced structural transitions such as metallization and the molecular-to-monatomic transition.     

光解CF3I研究I(52p1/2)的动力学

 本实验用YAG激光器的四倍频光,光解CF₃I得到I(5²P_1/2)。通过测量I(5²P_1/2)跃迁到基态而发出的1.315 μm荧光得到I(5²P_1/2)的自发辐射寿命为0.0370.005s,测得CF₃I、O₂、He对I(5²P_1/2)的猝灭常数分别为0.605Pa^-1s^-1,2 .25Pas^-1及0.22Pas^-1。     

氧碘激光器碘分子荧光光谱的计算机拟合

 用计算机光谱拟合的方法研究了氧碘化学激光器腔内碘分子的荧光光谱,计算结果显示碘分子B态各振动能级的粒子在振动量子数为16的粒子密度最大,且按高斯分布时,数值拟合光谱和实验采集的光谱基本一致。     

Chemical oxygen-iodine laser with external production of iodine atoms in CH3I/Ar dc glow discharge

A cw chemical oxygen-iodine laser (COIL) operating in a subsonic mode with a high water content of ～15% and external production of iodine atoms in CH₃I/Ar dc glow discharge has been demonstrated. A straightforward comparison of COIL performance for two cases—conventional, when I₂ was injected in the singlet oxygen flow, and when iodine atoms produced externally together with other discharge products were injected—was made. In the latter case nearly four times increase in output power was observed, suggesting that the relaxation of the energy stored in the singlet oxygen slowed down substantially, when the laser operated using CH₃I/Ar discharge products instead of iodine molecules.     

The129I hyperfine interaction in fatty acids studied by Mössbauer spectroscopy

Oleic acid substituted by iodine and saponified by Ca²⁺ cations has been studied by¹²⁹I Mössbauer spectroscopy. The quadrupole coupling constants and isomer shifts, determined from the γ-resonance spectra recorded at 4.2 K, have been described by 5p and 5s orbital populations of iodine. It was also found that saponification of the fatty acid has no significant influence on the measured iodine bonds. However, the increased order of fatty acids in soap form is reflected by narrowing of the resonant linewidth due to the reduction of the electric field gradient distribution.     

Multiphoton ionization of iodine atoms and CF<Subscript> 3</Subscript>I molecules by XeCl laser radiation

We report about effective ionization of iodine atoms and CF₃I molecules under the action of intense XeCl laser radiation (308 nm). The only ion fragment resulting from the irradiation of the CF₃I molecules is the I⁺ ion. We have studied the influence of the intensity, spectral composition, and polarization of the laser radiation used on the intensity of the ion signal and the shape of its time-of-flight peak. Based on the analysis of the results obtained, we have suggested the mechanism of this effect. The conclusion drawn is that the ionization of the iodine atoms by the ordinary XeCl laser with a nonselective cavity results from a three- (2 + 1)-photon REMPI process. This process is in turn due to the presence of accidental two-photon resonances between various spectral components of the laser radiation and the corresponding intermediate excited states of the iodine atom. The probability of ionization of the atoms from their ground state I(²P_3/2) by the radiation of the ordinary XeCl laser is more than two orders of magnitude higher than the probability of their ionization from the metastable state I^*(²P_1/2). The ionization of the CF₃I molecules by the XeCl laser radiation occurs as a result of a four-photon process involving the preliminary one-photon dissociation of these molecules and the subsequent (2 + 1)-photon REMPI of the resultant neutral iodine atoms.