Study on gold concentrate leaching by iodine-iodide

Gold extraction by iodine-iodide solution is an effective and environment-friendly method. In this study, the method using iodine-iodide for gold leaching is proved feasible through thermodynamic calculation. At the same time, experiments on flotation gold concentrates were carried out and encouraging results were obtained. Through optimizing the technological conditions, the attained high gold leaching rate is more than 85%. The optimum process conditions at 25℃ are shown as follows： the initial iodine concentration is 1.0%, the iodine-to-iodide mole ratio is 1：8, the solution pH value is 7, the liquid-to-solid mass ratio is 4：1, the leaching time is 4 h, the stirring intensity is 200 r/mim, and the hydrogen peroxide consumption is 1%.

Right time to detect urine iodine during papillary thyroid carcinoma diagnosis and treatment:A case report

BACKGROUND This is the first documentation of a spontaneous and nonspecific chemical reaction of an iodinated contrast media with ammonium persulfate used in As3+-Ce4+catalytic spectrophotometry for urine iodine concentration(UIC)detection.CASE SUMMARY We herein report an incidental case who had a dual source computed tomography examination for papillary thyroid carcinoma diagnosis.Serial spot urine specimens were collected during her hospitalization and were measured by As3+-Ce4+catalytic spectrophotometry on a Beckman Coulter AU5800.The reacted solutions were“brownish”,and the results showed extremely high iodine concentrations despite serial dilutions.The patient claimed no dietary habit of iodized salt or iodine-containing medical history,which strongly pointed to iodinated contrast media(ICM)via intravenous injection.Even with 0.01%ICM,its interruption is still profound on the desired urine iodine reaction with ammonium persulfate,leading to inaccurate UIC and possibly inappropriate treatment.CONCLUSION The following laboratory suggestions should be considered:(1)As3+-Ce4+catalytic spectrophotometry is only suitable for UIC measurement after confirmed ICM renal clearance;(2)A mass spectrometry-based method can be applied as an alternative during the ICM clearance period;and(3)The UIC baseline can be confirmed after ICM injection by consecutive detection for at least 2 mo.

The effects of thyroid-stimulating hormone,estradiol and prolactin on sodium/iodide symporter mRNA expression in mouse lactating mammary gland cells under different iodine levels

Objective The present study investigated the sodium/iodide symporter mRNA expression in mouse lactating mammary gland cells under different iodine levels and the effects of thyroid-stimulating hormone(TSH),estradiol(E2)and prolactin(PRL)on NIS mRNA expression in mouse lactating mammary gland cells.

Efficient capture of iodine and methyl iodide using all-silica EMM-17 zeolite

Hydrophobic zeolites have been identified as suitable adsorbents for capturing radioactive iodine species from nuclear-powerplant off-gas because of their high stability and strong water resistance.However,only the most common zeolites have been investigated for the capture of molecular iodine to date.Herein,we demonstrate that the composition and pore structure of zeolites considerably affect their iodine adsorption performance.A novel all-silica ExxonMobil material-17(EMM-17)zeolite having a unique three-dimensional 10(12)×10(12)×11-ring channel system exhibits a high adsorption capacity for iodine and methyl iodide in the presence of water.EMM-17 outperforms previously reported zeolites in terms of gravimetric and volumetric adsorption capacity in dynamic adsorption measurements.The excellent iodine/methyl iodide capture properties are attributed to the combination of optimal pore size,high pore volume,strong hydrophobicity,suitable particle morphology.This study provides useful insights for designing efficient adsorbents for iodine capture.

Electrochemically Generated Iodine Cations from a Glassy Carbon Electrode for Highly Selective Iodination of Anisole

The synthesis of aryl iodides from commercially available raw chemicals by simple,cheap and green strategies is of fundamental signifi cance.Aryl iodides can undergo a series of homo-/cross-coupling reactions for the synthesis of important industrial chemicals and materials.Traditional methods require the electrophilic substitution on aromatic compounds by iodine or hypervalent iodine compounds,which suff ers from the use of erosive halogens or hazardous oxidants.With the development of green chemistry in the fi eld of electrochemical synthesis,anodic oxidation-derived I^(+)cations have been used for substitution reactions.However,the selectivity of the iodination by these electrochemical methods remains unsatisfactory.We believed that the anolyte is contaminated by trace platinum species from the working electrode.Herein,we report the generation of active I^(+)species from the anodic oxidation of I_(2) in acetonitrile using a glassy carbon electrode.With the presence of H^(+),electrolyte prepared with a glassy carbon anode can react with anisole to selectively form 4-iodoanisole with a yield as high as 97%.On contrast,the electrolytes prepared from Pt and graphite anodes fi nished the reaction with yields of 16%and 60%for 4-iodoanisole,respectively.This electrochemical method also applies to the iodination of toluene,benzonitrile and bromobenzene,delivering the target para-iodination products with 92%,84%,and 73%yields,respectively.Thus,an atom-effi cient and highly selective aryl iodination method was developed without the use of excessive oxidants.

Urine Iodine, Estrogen, and Breast Disease

Introduction: We sought to explore iodine status (expressed as urine iodine excretion) in a group of women with a variety of breast diseases to characterize the relationship between iodine and breast physiology. Methods: Demographic and clinical data were recorded and random urine iodine levels were checked in 415 euthyroid patients over 5 years during clinic visits. Results: Pre menopausal women excreted less iodine in their urine than post menopausal women. Post menopausal women who took hormone supplementation had an excretion level similar to pre menopausal women. Women with breast cancer excreted less iodine than those without, and iodine excretion increased after treatment with aromatase inhibitors. Conclusions: These results demonstrate that there is a relationship between estrogen status and iodine excretion in euthyroid women. This suggests that there may be a threshold for total body iodine required for prevention of breast disease.

Application and Perception of Potassium Iodide Following Silver Diamine Fluoride Treatment

Silver Diamine Fluoride (SDF) is colorless and alkaline with a pH of 10. It has been used in Japan and other international countries for decades. The Food and Drug Administration gave approval for it as a means of treating hypersensitivity for individuals with chronic teeth pain. SDF is also used as a method to treat and arrest dental caries. SDF application is limited due to its negative esthetic effects, which is a black stain where the cavity was present on the tooth. Topical application of potassium iodide applied immediately after SDF has been shown in studies to reduce the color change caused by SDF. This study used topical application of silver diamine fluoride (SDF) and potassium iodide (KI) treatments on bovine teeth to determine if SDF and KI were efficacious in the treatment for carious lesions. The color change was detected by use of spectrophotometric analysis to determine L, a and b readings that demarcate light and color values following staining. The conclusion was made that the application of SDF followed directly by KI treatment produced L, a and b spectrophotometric values that indicated a significant reduction in teeth staining than the application of SDF alone. Therefore, this study supports the idea that SDF and KI can be used to treat carious lesions on bovine teeth while retaining surface enamel coloration.

Iodide analysis by ion chromatography on a new stationary phase of polystyrene-divinylbenzene agglomerated with polymerized-epichlorohydrin-dimethylamine

A new stationary phase for iodide ion analysis has been developed. The cationic polymerepichlorohydrin-dimethylamine（PEPI-DMA） was served as modifier in synthesizing polyelectrolyte sorbents and the macroporous polystyrene-divinylbenzene（PS-DVB） resin was used as support. The positively charged polymer（PEPI-DMA） was electrostatically bonded to a negatively charged particle（PS-DVB sulfonated）. The new stationary phase was characterized by scanning electron microscopy（SEM）, Fourier transform infrared（FTIR）, elemental analysis, chemical adsorption and desorption measurements. The chromatographic evaluation of the new stationary phase was performed using various anions with a conductivity detector. The new stationary phase was also applied to the determination of iodide directly with a DC amperometric detector using a platinum working electrode and an Ag/Ag Cl reference electrode. The chromatographic conditions were optimized and the eluent solution contained 5 mmol/L HNO3 and 15 mmol/L Na NO3 at a flow rate of 1.0 m L/min and column temperature of 30 8C. The applied voltage of the DC amperometric detector was 0.9 V. Under the optimum conditions, the linear range of the method was 0.2–50 mg/L for iodide ion with a correlation coefficient of 0.9990. The detection limit was 0.05 mg/L（calculated at S/N = 3） and the relative standard deviations（RSD, n = 6） were all less than 1% for retention time, peak area and peak height. This method was also utilized for the determination of iodide ions in samples of povidone iodine solution and kelp samples with satisfactory results.

Interaction of benzene-1,3-disulfonylamid-kriptofix[22] with iodine in chloroform and dichloromethane solutions

The interaction of iodine as an cr-acceptor with a synthetic ligand,benzene-1,3-disulfonylamid-kriptofix[22]（BDSAK） as a π-donor has been investigated spectrophotometrically in chloroform（CHCl3） and dichloromethane（DCM） solutions.The results of mole ratio plots and Job＇s method show the stoichiometry of complexation I2/BDSAK is 1：1.Stability constants have been calculated in various temperatures and thermodynamic parameters have also been determined from the temperatures dependence of the stability constants by using van＇t Hoff equation.The results indicate the iodine complex with BDSAK is enthalpy stabilized but entropy destabilized.

Adenovirus-mediated and tumor-specific transgene expression of the sodium-iodide symporter from the human telomerase reverse transcriptase promoter enhances killing of lung cancer cell line in vitro

Background The sodium-iodide symporter （NIS） protein can mediate the active radioiodine uptake.The human telomerase reverse transcriptase （hTERT） promoter is known to be selectively reactivated in majority of tumors and hence could be used for tumor targeting.We constructed a recombinant adenovirus containing the human sodium iodide symporter （hNIS） gene directed by the hTERT promoter, characterized the ability of infected cells in uptaking iodide, and explored the therapeutic efficacy of 131I in a lung cancer cell line in vitro.Methods The hTERT promoter was amplified by PCR from DNA isolated from log-phase HepG2 cells, subcloned into lineralized FL＊-hNIS/pcDNA3, and then the hTERT-hNIS sequence was subcloned into the shuttle plasmid pAdTrack.The recombinant adenovirus Ad-hTERT-hNIS was constructed by AdEasy system.A positive control adenovirusAd-CMV-hNIS and a negative control adenovirus Ad-CMV were created similarly.A549 cells were transduced with recombinant adenoviruses.125I uptake studies and sodium perchlorate suppression studies were used to confirm hNIS expression and function.Toxic effects of 131I on tumor cells were studied by in vitro clonogenic assay.Results We first successfully constructed an adenovirus mediated transgene expression system of the hNIS under the control of hTERT promoter.When infected with recombinant adenovirus constructs expressing hNIS directed by hTERTand CMV-promoters （Ad-hTERT-hNIS and Ad-CMV-hNIS, respectively）, the lung cancer cell line A549 had increased ability to uptake radioiodide up to 23- and 30- fold compared to the control parental cells, respectively.The radioiodide uptake ability of both the Ad-CMV-hNIS and Ad-hTERT-hNIS transduced cell lines were repressed 11-fold by sodium perchlorate （NaCIO4）.The subsequent in vitro clonogenic assay of the infected A549 cell line was further repressed to 23% （Ad-CMV-hNIS） and 30% （Ad-hTERT-hNIS） of the control group after receiving radioiodide for 7 hours （P 〈0.001）.Conclusion Our preliminary study indicates that an adenovirus mediated transgene expression system of the hNIS under the control of hTERT promoter has the potential to become an effective wide-spectrum yet highly specific anti-cancer strategy.

ELECTROCHEMICAL MEASUREMENT OF KINETIC ANALYSIS-AUTOMATIC DETERMINATION OF TRACE IODINE IN NATURAL WATERS

Ⅰ. INTRODUCTION Practically a great number of catalytic reactions can be converted into quite simple first-order reactions. Using the ever-expanding electrochemical technique, one can determine the reaction rates of many catalytic systems so conveniently that it

Insight into the formation of iodinated tr ihalomethanes dur ing chlor ination,monochloramination, and dichloramination of iodide-containing water

In this study, the formation of iodinated trihalomethanes(I-THMs) was systematically evaluated and compared for three treatment processes-(i) chlorination,(ii) monochloramine, and(iii) dichloramination-under different p H conditions. The results demonstrated that ITHM formation decreased in the order of monochloramination > dichloramination > chlorination in acidic and neutral p H. However, the generation of I-THMs increased in the dichloramination < chlorination < monochloramination order in alkaline condition. Specifically, the formation of I-THMs increased as p H increased from 5 to 9 during chlorination and monochloramination processes, while the maximum I-THM formation occurred at pH 7 during dichloramination. The discrepancy could be mainly related to the stability of the three chlor(am) ine disinfectants at different p H conditions. Moreover, in order to gain a thorough insight into the mechanisms of I-THM formation during dichloramination, further investigation was conducted on the influencing factors of DOC concentration and Br/Imolar ratio. I-THM formation exhibited an increasing and then decreasing trend as the concentration of DOC increased from 1 to 7 mg-C/L, while the yield of I-THMs increased with increasing Br/Imolar ratio from 5:0 to 5:10. During the three processes mentioned above, similar I-THM formation results were also obtained in real water, which indicates that the excessive generation of I-THMs should be paid special attention during the disinfection of iodide-containing water.

Arene C-H Iodination Using Aryl Iodides

Metathesis reactions represent powerful synthetic tools that have been used in a number of fields from the synthesis of natural product to functional material preparation.However,the C-H metathesis reaction is extremely rare.Herein,we report the first Pd(Ⅱ)-catalyzed C-H iodination of arenes using 2-nitrophenyl iodides as the mild iodinating reagents via a formal metathesis reaction.Unusual C-I bond formation occurred with aryl iodides in preference to competing C-C coupling in this reaction.Assisted by aliphatic carboxyl directing groups,a range of hydrocinnamic acids and related arenes could be selectively iodinated at either meta-or orthopositions of the phenyl ring.Remote diastereoselective C-H activation was also promising.This method might unfold a novel approach to iodinate challenging substrates.

Stereospecific Synthesis of （Z）-α-Fluoro-β-trifluoromethyl Vinyl Iodides and Their Application to the Synthesis of Polyfluorinated Thienyl Alkadienes

The direct iodination of polyfluorinated vinyl stannanes by tin-iodine exchange methodology was achieved giving （Z）-α-fluoro-β-trifluoromethyl vinyl iodides stereospecifically. Changing the substituent in R group from the electron-withdrawing group to electron-donating group led to an increase in the yield from 78% to 90%, while it was moved from para to meta position the reaction did not afford a dramatic change in the yield （90% to 95%）. In addition, this reaction also can be applied to the vinyl stannane with heterocyclic group. The further coupling reaction of prepared vinyl iodide containing heterocyclic moiety with （Z）-α-fluoro-β-trifluoromethylstannanes gave polyfluorinated heterocyclic alkadienes with 2E,4E-selectivity.

电感耦合等离子体发射光谱(ICP-OES)法测定含碘附银硅胶样品中碘含量

附银硅胶可以吸附放射性碘,形成含碘的附银硅胶,是后处理厂中常用的碘废物吸附材料。含碘附银硅胶样品中碘含量的准确测定能够验证碘的吸附效率,为后处理过程提供数据支持。含碘附银硅胶样品中银离子和碘离子形成难溶的碘化银,在溶解过程中难以将碘化银中碘离子定量转化为可溶解的碘离子、碘单质或者碘酸根,因此含碘附银硅胶样品中碘含量的测试方法比较困难。通过查阅银化合物的溶度积常数,考虑掩蔽银离子对碘离子的影响,在实验中采用加入硫离子的方法,生成比碘化银更难溶的硫化银沉淀,从而消除银离子的干扰。置换出的碘离子能够在碱性溶液中稳定存在,因碘含量较高,可采用电感耦合等离子体发射光谱法(ICP-OES)测定其含量。实验过程中考察了硫化钠加入量、氨水浓度、超声时间等对结果的影响。结果表明,硫化钠加入量与样品中银的含量有关,需要加入过量的硫离子沉淀银离子,不同的氨水浓度影响碘的灵敏度,而超声时间对结果基本无影响,优化实验条件后得到方法的检出限为0.52 mg/g,分别测量两个不同含量的含碘附银硅胶样品,平均值(n=6)为34.8 mg/g和59.3 mg/g,相对标准偏差为2.7%和2.0%,加标回收率为95.0%~103%。方法能够满足含碘附银硅胶样品中碘含量的测定。

Spectrophotometric Determination of Lodine in Soils by Chloramine T-Tetrabase System

Optimized the experimental conditions of determination of trace iodine in soil in chloramine T-Tetrabase system, and analysis the national standards material, the results showed that the measured values was to be identical with recommended values with a detection limit of 0.16 μg/g, and the relative standard deviation was less than 8%, the whole process was short in time and simple, so it was applicable to the determination of trace iodine in batches.

碘油与碘水子宫输卵管造影术对不孕症患者输卵管异常检出率和妊娠结局的临床对比研究

目的比较碘油与碘水子宫输卵管造影术应用于不孕症患者输卵管异常检出率和妊娠结局的效果。方法回顾性分析2021-01—2021-12郑州大学第二附属医院行子宫输卵管造影术的100例(200条输卵管)不孕症患者的临床资料。根据应用的造影剂分为碘油组及碘水组,每组50例(100条输卵管)。2组均于子宫输卵管造影术后行宫腹腔镜探查。比较2组患者的基线资料。以宫腹腔镜探查结果为依据,统计2组输卵管异常的检出效能、输卵管异常类型、妊娠率、早期流产率、异位妊娠率、多胎妊娠率,以及各组开始妊娠与造影术的间隔时间。结果宫腹腔镜探查结果显示,碘油组中输卵管异常68条、通畅32条;碘水组中输卵管异常62条、通畅38条。造影剂检查结果显示,碘油组中异常输卵管51条、通畅输卵管32条;碘水组中异常输卵管48条、通畅输卵管37条。以宫腹腔镜探查结果为依据,以异常输卵管为阳性,通畅输卵管为阴性。碘油组异常输卵管的诊断敏感度、特异性、准确性、阳性预测值分别为75.00%、100.00%、83.00%、100.00%;碘水组分别为77.42%、97.37%、85.00%和97.96%,一致性均较好(Kappa≥0.75)。2组差异无统计学意义(P>0.05)。碘油组1 a内的临床妊娠率、早期流产率、多胎妊娠率、异位妊娠率分别为44.90%、6.00%、0.00%、4.00%;碘水组分别为60.00%、2.00%、2.00%和0.00%。2组差异无统计学意义(P>0.05)。碘水组的妊娠与造影术间隔时间为(3.89±0.51)个月,短于碘油组的(4.25±0.40)个月,差异有统计学意义(P<0.05)。结论应用碘油与碘水造影剂行子宫输卵管造影术均能有效诊断输卵管通畅性,碘水造影剂可缩短术后妊娠间隔时间。

水中碘化物的3种测定方法比较

目的:通过离子色谱法、硫酸铈催化分光光度法、电感耦合等离子体质谱法3种方法测定水中碘化物,通过实验比较,分析3种方法的优缺点。方法:选取质控样品作为实验对象,按照3种方法实验步骤测定各实验组水中碘化物浓度。结果:3种检测方法线性关系均满足实际检测要求,且相关系数R^(2)≥0.999。电感耦合等离子体质谱法检出限为0.6μg·L^(-1),加标回收率为100.8%,相对标准偏差为0.36%~0.45%;硫酸铈催化分光光度法检出限为1.2μg·L^(-1),加标回收率为84.4%,相对标准偏差为0.80%~1.91%;离子色谱法检出限为8μg·L^(-1),加标回收率为91.4%,相对标准偏差为0.23%~1.11%。结论:3种检测方法检测范围广、灵敏度高,且精密度和准确度表现良好,均可准确测定水中碘化物的含量。

高碘对大鼠甲状腺TPO、TgmRNA表达及血清甲状腺激素的影响

目的观察不同水平的碘摄入对大鼠甲状腺功能的影响及其发病机理。方法断乳1月龄的Wistar大鼠90只随机分为6组,即低碘组(LI)、正常碘组(NI)、5倍碘组(5HI)、10倍碘组(10HI)、50倍碘组(50HI)和100倍碘组(100HI),分别饮用含碘量不同的水,饲养6个月后处死,摘取甲状腺,采用RT鄄PCR及放射免疫方法,检测甲状腺过氧化物酶(TPO)、甲状腺球蛋白(Tg)mRNA的表达和血清甲状腺激素水平。结果LI组、100HI组的血清甲状腺激素水平均低于NI组(P<0.01);NI、5HI、10HI、50HI组的血清TT4呈逐渐下降趋势,但各组间差异无统计学意义(P>0.05);100HI组TT4、FT4、rT3仍高于LI组(P<0.01)。从LI到10HI组大鼠甲状腺TPOmRNA表达水平随碘摄入量增加而呈逐渐减少趋势,而50HI、100HI组呈现回升趋势,经统计学分析,LI组高于NI组(P<0.05),10HI组低于NI组(P<0.05),50HI和100HI组与NI组差异无统计学意义(P>0.05)。甲状腺TgmRNA表达水平显示,6组间差异无统计学意义(P>0.05)。结论长期碘过量可导致甲状腺功能低下(甲低),与碘缺乏的后果相近,但甲低的程度不如碘缺乏性甲低严重;大鼠对高碘的摄入有很强的耐受性,在长期摄入高剂量的碘后,较严重碘过量时才发生明显的甲低;无论是碘缺乏还是碘过量所造成的甲低,都会引起代偿性的TPOmRNA的高表达,以促进?

适合缺碘及高碘地区水碘检测的方法研究

目的建立能测定不同质量浓度范围水碘样品的测定方法，以适用于不同地区水中碘的检测、方法不同碘质量浓度（0～10、0～100、100～600μg／L）的水样，取样量、砷铈浓度、反应时间以及测量波长是不同的取一定量的水样和标准溶液（低水碘0～10μg／L．水样先经过过硫酸铵消化）．加入亚砷酸溶液于30℃温浴15min，使用秒表计时，依顺序每管间隔15～30s向各管准确加入硫酸铈铵溶液．反应一段时间后．在特定的波长下进行检测，根据吸光度值的对数与含碘量呈线性关系计算水样含碘量：结果不同碘质量浓度范围（0～10、0～100、100～600μg／L）标准曲线的平均相关系数均〉0．9990；精密度在各个质量浓度范围内取高、中、低3个水样重复测定6次，其变异系数（CV）均〈2％：准确度在各个质量浓度范围内对低、中、高3种不同含碘量的水样加碘标平均回收率分别为99．7％、98．8%、99．3％（n=6）。结论检测方法操作简单，结果准确．适宜于不同地区水碘测定。