人造板甲醛释放量与环境温湿度、陈放时间关系研究

通过实验研究人造板甲醛释放量与环境温度、湿度及陈放时间之间的关系.结果表明:人造板甲醛释放量随环境温度升高而明显增加,随湿度的升高而缓慢增加,随陈放时间的增加甲醛释放量逐渐降低并趋于稳定.     

氡测量方法与标准氡室综述

本文介绍了常用的氡测量方法和测氡仪器,对氡测量技术进行了较详细分析,为选择适宜的方法进行氡浓度监测提供了参考。标准氡室的研制为各种测氡仪器的刻度和量值溯源性提供了技术支撑,保证了测量结果的准确可靠,文章简要介绍了国内外标准氡室的发展状况。     

连续测氡仪测定空气中氡浓度方法探讨

在民用建筑工程室内环境中氡浓度的测定方法中,用连续测氡仪测定氡浓度是一种方便、快捷的方法,但在实际检测过程中,由于操作等原因,仪器的测量准确度较低。在标准氡室(HD-1型)里模拟实验用标准氡浓度,以RAD7连续测氡仪为例,探讨了取样测量时间、空气湿度对空气中氡浓度测量的准确性的影响。结果表明,在取样测量时间不低于30min、较低空气湿度(10%)条件下,用连续测氡仪测量空气中氡浓度可以获得满意的数据。     

氡的性质及空气中氡浓度的测量综述

本文描述了氡的性质、危害及其在空气中浓度的测量方法，并对测量中应注意的问题提供了一些思考与建议。     

氡室与液体氡源校准氡钍分析仪比对

本文分别使用氡室和液体氡源对氡钍分析仪进行校准,介绍氡室和液体氡源的原理和校准方法,对校准的方法、过程、结果进行分析和探讨。     

五大连池氡矿泉水中氡含量特征分析

本文对五大连池地区氡矿泉水中氡含量进行了等级划分,并讨论了不同浓度氡矿泉水对应的医疗效果、使用方法及危害性。     

室内空气中氡的防护

介绍了氡的产生和特性,阐述了室内氡的来源,介绍了室内氡浓度的测量方法,由此总结了降低室内氡浓度的一些控制措施,以期创造健康的室内环境.     

酒柜内湿度的分析及实验研究

本文详细介绍了加湿的技术,以及酒柜内增加湿度的方法,并对酒柜进行湿度的实验测试。通过改变蒸发温度,得到在不同设定温度条件下内部的湿度变化情况,通过对实验结果的分析,提出了减小酒柜内部湿度波动的方法。     

地下水中氡含量的动态变化及其应用研究

氡是镭放射性衰变过程中产生的一种惰性气体，其化学性质很不活泼，但是可以吸附在固体物质中。通过对地下水中氡含量的测量，我们可以有效判断地震等地质、水文方面的变化。     

工业废渣基建材的氡放射性污染及防护的研究现状与展望

在科学发展观与建设和谐社会的倡导和号召下,建材工业也进入了可持续发展的时代,从而使工业废渣基建材的研究和使用成为热点.然而工业废渣中存在着氡和放射性污染.氡是一个"无形杀手",是导致肺癌的第二大因素,为人类居室环境的一大公害.对氡污染的危害和来源作了总结,介绍了目前国内工业废渣基建材的研究、发展和应用现状,综合国内防氡防辐射材料及防护技术的研究报道,提出了一些防氡防辐射技术在工业废渣基建材中的应用.     

Calibration of Electret-Based Integral Radon Monitors Using NIST Polyethylene-Encapsulated 226Ra/222Rn Emanation (PERE) Standards

The recently developed ²²²Rn emanation standards that are based on polyethylene-encapsulated ²²⁶Ra solutions were employed for a first field-measurement application test to demonstrate their efficacy in calibrating passive integral radon monitors. The performance of the capsules was evaluated with respect to the calibration needs of electret ionization chambers (E-PERM^®, Rad Elec Inc.). The encapsulated standards emanate well-characterized and known quantities of ²²²Rn, and were used in two different-sized, relatively-small, accumulation vessels (about 3.6 L and 10 L) which also contained the deployed electret monitors under test. Calculated integral ²²²Rn activities from the capsules over various accumulation times were compared to the averaged electret responses. Evaluations were made with four encapsulated standards ranging in ²²⁶Ra activity from approximately 15 Bq to 540 Bq (with ²²²Rn emanation fractions of 0.888); over accumulation times from 1 d to 33 d; and with four different types of E-PERM detectors that were independently calibrated. The ratio of the electret chamber response E_Rn to the integral ²²²Rn activity I_Rn was constant (within statistical variations) over the variables of the specific capsule used, the accumulation volume, accumulation time, and detector type. The results clearly demonstrated the practicality and suitability of the encapsulated standards for providing a simple and readily-available calibration for those measurement applications. However, the mean ratio E_Rn/I_Rn was approximately 0.91, suggesting a possible systematic bias in the extant E-PERM calibrations. This 9 % systematic difference was verified by an independent test of the E-PERM calibration based on measurements with the NIST radon-in-water standard generator.     

Uranium Separation from Phosphoric Acid Using Metallic Carbonaceous Structures as Efficient Adsorbents: an Experimental and Kinetic Study

Radiochemistry - The possibility of removing uranium species from commercial phosphoric acid using metal-modified biocarbon was examined. The biocarbon was prepared from a solid residue by...     

从锑矿石制备三氯化锑的工艺研究

用蒸馏－多级冷凝法从锑矿石制取高纯度三氯化锑，该方法具有设备和工艺简单，能耗以及产品纯度高等优点。     

Leaching of Uranium from Its Mineralization and Experimental Design of the Process

The central composite design (CCD) of experiments was used to study the leaching of uranium and iron from the mineralized Gabal Al-Aglab uranium ore sample using sulfuric acid solution. The leaching factors were sulfuric acid concentration, contact time, particle size, temperature, solid to liquid ratio, and stirring rate. The uranium and iron leaching efficiencies were 71.6 and 10.8%, respectively. Three factors were taken into consideration in the experimental planning: leaching time, solid/liquid ratio, and stirring rate. The obtained results were statistically analyzed using analysis of variances (ANOVA) to determine the main effects and interactions between the investigated factors.     

钨矿选矿工艺研究

对滇南某钨矿物与褐铁矿连生,两部分相互穿插的钨矿选矿工艺进行了研究.利用化学分离法进行选矿,研究制定了掺碱焙烧-浸煮-酸沉的选矿工艺.考察了不同的焙烧温度、浸煮时间、浸煮液固比、NaCO3加入量、NaNO3加入量对WO3含量及回收率的影响.结果表明,当焙烧温度在800℃,浸煮时间为50 min,浸煮液固比取4:1,NaCO3加入量为25 g,NaNO3为0.75g时,钨的回收率最高,可达24.02%,WO3的含量最高可达49.89%.