空气中苯系物含量测定方法的改进

用活性炭吸附-CS2（溶剂）解析气相色谱法测定空气中苯系物的含量,并对该方法的分离度、精确度、回收率等进行了测试。结果表明,该方法的主要技术指标符合环境空气监测的要求。对较难分离的对-二甲苯、间-二甲苯的分离效果很好。     

顶空-气相色谱串联质谱法测定修正液中六种苯系物

采用顶空-气相色谱串联质谱法测定修正液中六种苯系物,选用硅油作为基质,通过实验确认顶空平衡温度和平衡时间为:90℃和10 min,并进行了色谱条件的优化。该方法简单可靠,准确度高,线性范围为0.1~100 mg/kg,最低检测浓度为0.1 mg/kg,方法回收率为91.2%~96.4%,相对标准偏差为4.3%~7.9%。该方法可以准确定性、定量测定修正液中的6种苯系物。     

电子电气行业废水中苯系物的测定

以二硫化碳为萃取液,采用氢火焰离子化检测器气相色谱法检测废水中的八种苯系物。各目标物校正曲线相关系数在0.999以上。检测限为0.07~0.08μg/L,方法回收率为90.8%~101.6%,相对标准偏差为2.1%~2.8%。该方法适用于电子电气行业废水中苯系物的测定。     

罐采样/气相色谱-质谱法测定页岩气中的苯系物含量

建立了罐采样/气相色谱-质谱法测定页岩气中苯系物含量的分析方法。用内壁惰性化处理的不锈钢罐采集样品,经冷阱浓缩、热解析后,进入气相色谱分离,用质谱检测器进行检测。通过与标准物质质谱图和保留时间比较定性,外标法定量。全扫描模式下,苯、甲苯、乙苯、对二甲苯、间二甲苯、邻二甲苯的检出限为0.9μg/m3、1.0μg/m3、1.2μg/m3、1.2μg/m3、1.2μg/m3、1.2μg/m3,实验室内相对标准偏差为2.3%～6.6%、2.7%～6.3%、1.8%～6.7%、4.1%～10.5%、3.9%～9.9%、3.8%～7.5%。所建立的测定方法满足对页岩气中苯系物的痕量鉴定。     

气相色谱法测定污染源中的苯系物

采用活性炭采样管富集气污染源中的苯系物，以二硫化碳为解吸剂，经毛细管柱测定样品中的苯系物，以保留时间定性，峰面积定量。通过对样品的采样和前处理方法法方法进行了不同条件的探讨，得出了最佳的实验条件。本方法中苯系物各组分线性方程的相关系数均大于0．999，方法的最低检出浓度在15-39μg/m^3，加标回收率在95.3～101％之间，相对标准偏差小于4．5％（n=6），能满足实际工作的需要。     

气相色谱——质谱法对6种苯系物的测定

使用活性炭管吸附采样,二硫化碳溶液解吸,气相色谱-质谱联用仪测定,外标法定量测定工作场所中苯系物。HP-5 MS毛细管柱对苯、甲苯、乙苯、对二甲苯、间二甲苯、邻二甲苯化合物进行分离。标准曲线相关系数均大于0.999,相对标准偏差1.6%~3.2%,最低检出浓度0.16~0.25 mg/m3。方法简便,重现性好,准确度高,便于对工作场所空气中苯系物的定性和定量分析。     

吹扫捕集/气相色谱-质谱法测定土壤中苯系物的研究

基于吹扫捕集/气相色谱-质谱法进行污染土壤样本中苯、甲苯、乙苯、间二甲苯、对二甲苯、邻二甲苯与异丙苯等苯系物含量的测定,针对吹扫时间、解吸温度、解吸时间三项预处理环节的重要参数进行分析测定,最终确定以吹扫时间11min、解吸温度190℃、解吸时间30s作为最佳实验参数,完成土壤中苯系物的测定.测试结果显示,采用该方法测...     

室内空气中苯系物和TVOC检测

室内苯系物和总挥发性有机物(TVOC)是造成室内空气污染的主要原因之一.本文对这两类污染物实验室分析方法作了初步研究.并对杭州市室内苯系物和TVOC污染物浓度分布作了调查.     

电子鼻测定苯系物的方法研究

为考察电子鼻用于苯系物(BTEX)快速检测的可行性,分别采用电子鼻(zNose4200,GC/SAW)和普通气相色谱(GC522,FID)对其进行分析.结果表明:电子鼻的灵敏度均为普通气相色谱的10倍以上,最高可达140倍.此外,精密度和重现性也优于后者,可用于BTEX快速、实时分析,是一种用于分析环境中挥发性和半挥发...     

气相色谱法测定颜料类产品中10种苯系物含量

采用外标法定量,建立了气相色谱法测定颜料类产品中10种苯系物含量的试验方法。实验结果表明,该方法在3.0～100.0 mg/kg范围内,线性良好,相关系数(r²)>0.999 5,检出限为0.2～1.3 mg/kg。按照建立的方法进行了三个不同添加量加标回收试验,回收率为92.1%～111.9%,测定值的相对标准偏差(RSD)为0.61%～3.15%(n=6)。通过实际样品测定发现,部分颜料类产品检出了苯、二甲苯、苯乙烯和少量的三甲苯。     

New printing inks with barrier performance for packaging applications: Design and investigation

Barrier properties of packaging materials against moisture and oxygen penetration are of high relevance. Enhanced protection of existing materials against weather conditions can be achieved by application of printed coatings. To improve barrier performance of packaging materials, new inks for obtaining printed coatings with a layered structure were developed and investigated. The proposed ink compositions for flexographic printing on paper substrates are based on an environmentally friendly acrylic binder and contain inorganic fillers with platelet particles incorporated in the polymer matrix. Coatings based on the developed printing inks demonstrate significantly decreased water vapour permeability compared to traditional polymer inks. The effect of decreased permeability was investigated considering inks rheological behaviour, the coating structure, mechanical properties, surface energy and water uptake for different ink formulations. The developed inks provide variable optical properties including coatings with a relatively high transparency. The development of the functional barrier inks contributes to saving natural resources by prolonging life performance of packaging materials and goods.     

食品包装材料用无毒干法覆膜胶乳液的研制

以醋酸乙烯酯(VAc)和甲基丙烯酸甲酯(MMA)为硬单体、丙烯酸丁酯(BA)为软单体、交联单体(TM-200)/丙烯酸(AA)为复合交联剂、叔丁基过氧化氢(TBHP)/甲醛合次硫酸钠(吊白块)为氧化-还原型引发剂、可聚合型阴离子乳化剂(SVS-25)为环保型乳化剂和Gohsefimer Z-210为改性保护胶体,采用乳液聚合法制备出食品包装材料用无毒干法覆膜胶。研究结果表明:采用减压脱除及后添加氧化-还原型引发剂,可使覆膜胶中残余单体含量降至0.01%以下;当m(VAc)∶m(MMA)∶m(BA)=30∶10∶60、乳化剂中m(SVS-25)∶m(Gohsefimer Z-210)=1∶1、w(乳化剂)=2.0%和w(氧化-还原型引发剂)=0.20%时,覆膜胶的综合性能相对最好。     

Gravure offset printing of polymer inks for conductors

A gravure offset printing process has been developed for Ag-filled polymer conductor ink. Pad printing and roller type printing have been used. Curing and electrical properties have been studied. A roller type of gravure offset printing has been used to evaluate the printing process and pad printing to print on the non-planar substrates. Based on differential scanning calorimetry (DSC) and resistivity measurements during ink curing, it was found that the ink had an optimum curing temperature of 140 °C. Square resistance of 300 and 150 μm wide lines can be as low as 20 and 28 mΩ/sq., respectively, for 7–8.5 μm thick line. The minimum line width was 70 μm. This minimum line width can be reduced with different ink solvents, but in this case the line thickness suffers and the square resistance increases, respectively.     

Methods for the evaluation of fine-line offset gravure printing inks for ceramics

The printing of ceramic substrates by offset gravure is well established industrially and is a potentially viable method for printing circuitry. Modified inks are required to be able to print fine lines at high resolution with minimal displacement and distortion. In the present study a statistical assessment of the role of the components of the ink binder has been undertaken, the inks being evaluated by printing tests and in terms of their rheology and cohesion. The results have been examined using a factor design program and the best-fit multivariate model established in order to describe the response to each factor. Based on the models, it was possible to increase the internal cohesion of the inks which gave a decrease in the rheological phase angle and an increase in print mass. It was found practicable to print lines as fine as 9 mm wide and dots as small as 20 mm diameter on ceramic substrates.     

Gravure printing of conductive particulate polymer inks on flexible substrates

A roto-gravure printing technique has been developed for conductive lines on paper and plastic films. Rotary-screen-printing was used to make comparative prints. The inks contained metal particles in an organic medium and were cured in temperatures of 70–120 °C, limited by the substrate durability. The following conductor line properties were characterised for different substrates: resistance, yield as a function of line width, coil inductance, folding endurance, adhesion, printed antenna properties and maximum current density. A printed resistance down to 50 mΩ/□ was obtained, with conductor lines 4–7 μm thick. Minimum line resolution and resistance were affected by smoothness of substrates. Adhesion properties were adequate for the studied components.     

Surface-modified and micro-encapsulated pigmented inks for ink jet printing on textile fabrics

Surface-modified and micro-encapsulated pigment dispersions were formulated into pigmented ink jet inks and their properties were analyzed. The changes in viscosity, and particle size distribution, and ink stability were observed every week for 12 weeks at ambient temperature. All the ink jet ink properties were in the operational range. As for appearance and color, the surface-modified pigmented inks printed on a silk fabric yielded higher optical densities, better tone reproduction, wider color gamut, and a larger gamut volume than the micro-encapsulated pigmented inks. For permanence and usability, the micro-encapsulated pigmented inks gave better fastness; the wear comfort of the printed silk fabric, evaluated by the bending stiffness, indicated a negative effect on the pre-treatment of the fabric. Surface pre-treatment of the textile fabrics affected color, appearance, permanence and usability. Despite almost equal numbers of threads, the fabric bending strength in the weft direction was much stronger than that in the warp direction.     

Wetting and adhesion of water-borne printing inks on surface-modified polyolefins

Polyolefin films were surface-modified by different methods to improve the wetting and adhesion of water-borne printing inks. Polyethylene (PE) films were treated with corona at various energy levels. Surface-modified PE films were characterized by contact angle measurements and electron spectroscopy for chemical analysis (ESCA). Good wetting was already achieved with treatment at a lower energy level. Various degrees of adhesion were obtained at various degrees of treatment. A hydrophilic monomer, 2-hydroxyethylmethacrylate (HEMA), was polymerized onto the surfaces of polypropylene (PP) with radiation-induced grafting, which was carried out at two different radiation doses. In both cases, a thick, visible layer of polyHEMA was formed on the surface of PP, and satisfactory wetting was already achieved at lower radiation doses. Scanning electron microscopy (SEM) showed that different degrees of roughness were achieved at various radiation doses. Like the case of corona-treated PE, different degrees of adhesion were obtained at different degrees of surface treatment. This study shows that improved wetting alone is not satisfactory for good practical adhesion', regardless of the surface modification method used.