靛酚蓝分光光度法测定室内空气中氨含量的应用研究

针对靛酚蓝分光光度法测定室内空气中氨浓度的有关问题进行了试验研究,通过试验和数据对比,对实验中的干扰因素、最佳测定条件、检测范围、精密度及回收率等进行了初步分析和讨论,并介绍了分析试验干扰因素的消除方法.     

离子色谱法测定萤石中氟化钙的含量

应用离子色谱法(ICS)测定萤石中氟化钙的含量。试样经氢氧化钾熔解,定容进行测定。同时进行了熔解试剂时测定结果的影响试验,并进行了一系列仪器测定精度及方法回收率试验。经过试验发现离子色谱法测定萤石中的氟化钙含量具有分析速度快、无干扰、灵敏度高、准确度高等优点,适合于大批量样品的检测,可以大大地提高工作效率。     

钛盐光度法测定Fenton氧化中的过氧化氢

采用钛盐光度法测定Fenton高级氧化中的过氧化氢,是基于在酸性介质中过氧化氢与钛离子生成稳定的橙色络合物的原理,通过分光光度法测定过氧化氢的含量.对钛盐用量、显色时间、溶液酸度和干扰离子等因素对测定结果的影响进行了分析,并在蒸馏水、存在有机物和Fenton高级氧化体系中,对高锰酸钾法、碘量法和钛盐光度法测定过氧化氢进行了对比试验.结果表明,钛盐光度法具有简便、准确、选择性好的特点,能有效克服氧化还原方法的缺陷.     

季铵盐杀菌剂对硬度测定的干扰与消除

采用EDTA滴定法测定循环水硬度时,季铵盐杀菌剂会对滴定产生干扰,导致无法观察滴定终点,为此分析了产生干扰的原因,并通过试验研究了消除干扰的三种方法.结果表明,四苯硼钠沉淀法、过硫酸铵氧化分解法和二甲酚橙指示剂法均可消除季铵盐杀菌剂对硬度测定的干扰,得到满意的测定结果.相比之下,四苯硼钠沉淀法操作简单、测定结果准确,更适合循环水硬度的现场监测.     

分光光度法测定硝酸盐氮中的干扰因素

对酚二磺酸分光光度法测定水样中硝酸盐氮的标准方法进行研究,在不同浓度的氯化物、氨氮和亚硝酸盐氮中加入不同浓度的硝酸盐氮标准溶液进行干扰试验。结果表明：在最佳的试验条件控制下,氯离子对低浓度硝酸盐氮测定产生的负干扰明显大于对高浓度硝酸盐氮产生的负干扰;随着加入的氨氮和氯化物浓度的增加,硝酸盐氮含量的测定结果低于实际值,且逐渐减小;在试验浓度范围内亚硝酸盐氮浓度对硝酸盐氮的测定几乎无影响。     

用火焰原子吸收法测定镀铬泥渣中的铁、镍、铜、锌、铅

本文研究了火焰原子吸收法测定镀铬泥渣中Fe、Ni、Cu、Zn、Pb时,共存元素的干扰及其消除方法。试验发现,Cu对Ni的测定,Ni、Si对Fe的测定有严重干扰;采用十二烷基硫酸钠或柠檬酸作为干扰抑制剂可消除大量Cu对Ni及Si对Fe、Zn测定的干扰;降低乙炔流量,提高空气—乙炔比,可消除Ni对Fe测定的干扰。本方法简便、快速、准确,用于实际样品分析可得到满意的结果。     

水样预处理后对氨氮测定的影响因素研究

工业废水的色度会对氨氮测定产生干扰,特别是氨氮浓度较低时,对测定影响更大,故需对水样进行预处理。通过采用蒸馏法对水样进行预处理,分析水样经预处理后,影响氨氮测定特性研究。正交试验结果表明,氨氮测定的最主要影响因素是预处理后水样的p H值,其次是反应温度和显色时间。单因素实验表明,水样经过蒸馏预处理后需将其p H值调节到9.0~9.5,显色时间控制在10~30 min左右,反应温度控制在20℃左右,才能保证测定结果的准确性。     

叠加法测定污水处理厂高氯出水水样的COD

在污水厂高氯出水水样COD的测定过程中,氯化物是主要干扰物质,如何选取最好的测定方法而避免和消除其干扰是测定的关键.为此,通过对天津泰达威立雅水务有限公司污水处理厂出水水质的分析,将出水水样分为可滤和不可滤两部分,分别用国标法和标准曲线校正法进行COD的测定,其和就是出水水样COD的最终结果.大量试验证明,此方法测定结果准确、可靠.     

钢结构螺栓抗滑移连接件滑移系数检测

现有螺栓抗滑移连接件进行抗滑移系数检测试验中干扰因素较多,对试验结果准确度影响较大。采取自制抗滑移试验辅助设备可减少人为因素干扰,以精确测量抗滑移连接件抗滑移载荷,分析抗滑移连接件抗滑移性能。     

气相色谱—电子捕获检测法测定水中5种农药残留

目的利用气相色谱—电子捕获检测法同时测定水中莠去津、林丹、百菌清、毒死蜱和溴氰菊酯5种农药残留。方法水样经液液萃取,无水硫酸钠脱水后直接进样测定;针对影响回收率的因素进行了试验,优化了溶剂的选择及用量、氯化钠用量;采用外标法定量,进行低、中、高三个添加水平的加标回收率测定,每个水平测定6次。结果该方法在测定的含量范围内标准曲线线性关系良好,相关系数均>0.999 6,方法检出限为(0.01～0.30)μg/L,3种浓度的水样加标回收率为90.5%～110.0%,相对标准偏差(RSD)为0.4%～3.2%。结论该方法样品无需浓缩,操作简便、干扰少、分析速度快、灵敏度高、线性良好、精密度和准确度均较好,适用于水样中5种农药残留的测定。     

基于改进遗传算法的建筑室内空气品质评价

在分析室内空气品质的关键影响因素的基础上，提出采用改进的GA遗传算法应用于室内空气品质评价测试，给出了改进遗传算法室内空气品质综合评价的基本原理，对江门市室内空气实测数据进行了综合评价对比，验证了所提出评价法的有效性。     

夏热冬冷地区高大公用建筑空调能耗特性分析

利用Energyplus软件对夏热冬冷地区高大公用建筑空调能耗进行模拟分析,通过正交试验法研究空调能耗受负荷影响因子的影响情况,给出的影响因子排序为设备负荷〉照明负荷〉人员密度〉室内设计温度〉新风量〉窗墙比〉外窗传热系数〉屋面传热系数〉遮阳系数〉外墙传热系数;进一步研究围护结构的影响因子与空调节能的关系,拟合得到节能率与围护结构影响因子间的回归方程,用于指导建筑空调节能设计及改造。     

Psychosocial dimensions of solving an indoor air problem

This investigation focuses on the psychological and social dimensions of managing and solving indoor air problems. The data were collected in nine workplaces by interviews (n = 85) and questionnaires (n = 375). Indoor air problems in office environments have traditionally utilized industrial hygiene or technical expertise. However, indoor air problems at workplaces are often more complex issues to solve. Technical questions are inter-related with the dynamics of the work community, and the cooperation and interaction skills of the parties involved in the solving process are also put to the test. In the present study, the interviewees were very critical of the process of solving the indoor air problem. The responsibility for coordinating the problem-managing process was generally considered vague, as were the roles and functions of the various parties. Communication problems occurred and rumors about the indoor air problem circulated widely. Conflicts were common, complicating the process in several ways. The research focused on examining different ways of managing and resolving an indoor air problem. In addition, reference material on the causal factors of the indoor air problem was also acquired. The study supported the hypothesis that psychosocial factors play a significant role in indoor air problems.     

民用建筑室内新风量检测方法影响因素的研究

新风对于稀释室内空气中的有害物质、改善室内环境有着重要的意义。新风量则是衡量新风的有效手段,目前不设独立新风系统的建筑室内新风量测量广泛采用CO_2示踪气体法。本文通过一系列实验探讨CO_2初始浓度、门窗开关方式、室外风速以及室内杂物对室内新风量检测结果的影响。实验结果表明CO_2初始浓度、门窗开关方式、室外风速、室内杂物这些因素均对新风量检测值均存在不同程度的影响,其中室外风速和室内有无杂物对新风量检测结果的影响最为明显。     

基于正交试验的工业厂房自然通风影响因素数值分析

本文以一间大空间工业厂房为例,运用CFD模拟工具计算了自然通风条件下厂房的室内平均温度与通风量.而后,采用正交试验方法比较分析了5种外界因素水平同时变化时单个因素对室内平均温度和通风量作用的主次顺序及影响趋势,并将模拟数据拟合成了相关关系式,为工程实践中高效预测自然通风效果提供了一种方法.     

Effect of indoor buoyancy flow on wind-driven cross ventilation

Designing for wind-driven cross ventilation is challenging due to many factors. While studies have focused on the difficulty of predicting the total flow rate and measuring opening characteristics of cross ventilation, few have investigated the impacts on the distribution of indoor air. This paper provides insights on how local heat sources can generate significant buoyancy driven flow and affect indoor mixing during wind-driven cross ventilation scenarios. Measurements of air distribution were conducted by a tracer gas method for a multi-zone test building located in Austin, Texas, USA, along with cross ventilation flow at the openings. A computational fluid dynamic (CFD) model was also developed for this test building, which utilizes the measured flow properties at the openings as boundary conditions. Resulting air distribution patterns from the CFD model were then compared to the experimental data, validating the model. Further parametric analyses were also conducted to demonstrate the effect of interior heat loads in driving internal air mixing. Key findings of the investigation suggest a local heat source smaller than 35 W/m² can increase the indoor mixing during cross ventilation from less than 1 air exchange to as high as 8 air exchanges per hour. This result also suggests a typical occupancy scenario (people and electronics) can generate enough heat loads to change the indoor air mixing and alter the effect of cross ventilation.     

Multivariable control of indoor air temperature and humidity in a direct expansion (DX) air conditioning (A/C) system

Controlling indoor humidity at an appropriate level is very important since this affects occupants' thermal comfort and indoor air quality (IAQ). The paper presents an investigation on developing a multi-input multi-output (MIMO) control strategy for simultaneously controlling the indoor air temperature and humidity by varying the speeds of both compressor and supply fan in an experimental DX A/C system. The MIMO-based controller was designed based on the linearized dynamic model of the experimental DX A/C system. The Linear Quadratic Gaussian (LQG) technique was used in designing the MIMO-based controller. The controllability tests with respect to both the disturbance rejection capability and the command following capability were carried out to assess the control performance of MIMO controller. The results of disturbance rejection capability test showed that the MIMO control strategy can effectively maintain the indoor air temperature and humidity to their respective settings after an unmeasured heat load disturbance was imposed by simultaneously varying speeds of both the compressor and the supply fan of the DX A/C system. Furthermore, in the command following capability test for indoor air temperature, the test results showed that the indoor air temperature can be controlled to its new setting while indoor humidity remained unchanged. Similar test results were also observed in the command following capability test for indoor humidity. Therefore, the MIMO controller developed can effectively control indoor air temperature and humidity simultaneously by varying compressor speed and supply fan speed of the DX A/C system. Compared to the previous related studies using conventional on–off control method or single-input single-output (SISO) control strategy, which can only effectively control either air temperature or relative humidity, the MIMO controller can simultaneously control the indoor air temperature and humidity with adequate control sensitivity and accuracy. The application of MIMO control strategy developed can be extended to other HVAC systems in the future to improve their operating performance and energy efficiency.     

室内空气品质研究的探讨

针对室内空气品质是人们生活和工作最重要的环境因素之一,并通过目前国内外室内空气品质的定义和评价,分析了几种可能影响室内空气品质的因素,并探讨了空气质量的控制问题,从而充分改善室内空气品质。     

广州居住建筑空调能耗实测研究

对一栋9层住宅楼顶层和8层的两住宅单元作了空调能耗和室内温度的实测，介绍了住户的空调使用情况。将实测数据与采用DOE-2程序所作理论计算结果加以比较，分析了影响空调能耗的屋顶构造、窗墙比、室内设定温度等关键因素。     

藏族闪片木楞房热环境测试与分析

对香格里拉藏族早期民居冬季室内的热环境进行了热环境测试,具体对木楞房民居室内温度、围护结构各壁面温度等参数进行了测试,比较分析,测试结果反映出影响室内热舒适性的温度变化现状,为改善室内热环境的舒适性提出改进建议和措施。