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1.
利用顶空气相色谱法和加速老化技术研究了工业红磷中微量杂质对磷化氢产生的影响以及减慢磷化氢产生的方法。混入抑制剂可以减慢磷化氢的释放速度,加入纳米氢氧化镁可大大减慢磷化氢的生成速度小于而使之04mg/(m3·d),而且红磷的分散性和流动性很好。  相似文献   

2.
消光电泳涂料的研究重点是降低材料的光泽,并且达到优异的性能。文章主要介绍铝型材消光电泳的特点、消光原理以及各种不同消光手法。电泳涂料为了得到消光的外观,可以通过两种手段获得:物理消光和化学消光。物理消光法主要采取电泳后处理以及在涂料中添加消光剂来达到消光的目的,化学消光法利用树脂之间的性能差异来降低光泽。文章重点阐述了树脂消光法的原理以及在消光电泳涂料中采取的方法,包括溶解性(SP)差异消光法、内微凝胶消光法、固化温度差消光法等,指出消光树脂的研究方向是制备出能够抑制电解气发生的树脂,使阴极消光电泳涂装成为可能。  相似文献   

3.
某红外干扰烟幕材料中镁、铝、铜元素的含量直接影响其干扰性能。化学滴定法是测定金属元素含量的传统方法,但这种方法过程繁琐、冗长,只能依次测定,且在铝和铜同时存在下无法对镁元素定量分析。建立了一种采用浓硝酸消解样品,对消解液过滤、稀释后直接用电感耦合等离子发射光谱(ICP-OES)法测定某红外干扰烟幕材料中镁、铝、铜元素含量的方法。当Mg、Al、Cu的分析线选择279.5、167.0和324.7 nm时,其检测限分别达到0.013、0.040和0.025μg/mL,且样品测定的加标回收率均在102%~105%,相对标准偏差在1.0%~3.0%(n=8),表明方法的准确度和精密度均良好。还对方法的总标准偏差进行了溯源,并与络合滴定法结果进行了比较。显著性检验表明两种方法的结果无显著性差异,但ICP-OES法更简便、快速,并能对三种元素同时测定,因此可完全替代传统的化学滴定法。  相似文献   

4.
亚光涂料具有光泽柔和的特点,能够提供舒适温馨的氛围,降低视觉疲劳,在建筑、车饰、医疗、交通等日常生活领域具有广阔的应用空间。目前亚光涂料主要通过加入消光剂和消光树脂来实现消光。本文综述了近年来消光剂和消光树脂在各类亚光涂料中的研究进展,特别介绍了改性二氧化硅消光剂和新型消光树脂在紫外光固化涂料中的进展情况,总结了我国在消光剂和消光树脂研究中的不足之处,指出了目前消光剂和消光树脂在亚光涂料应用中存在的主要问题,并展望了其应用前景和发展趋势。  相似文献   

5.
陶承业  杨占旭  李玥 《应用化学》2020,37(9):1056-1061
研究了一种先通过机械球磨和水热法制得的亚微米红磷,再通过球磨亚微米红磷与石墨得到的块状亚微米红磷/石墨复合材料(smRP/G),并利用扫描电子显微镜(SEM)、X射线衍射(XRD)、X射线光电子能谱分析(XPS)、循环伏安法(CV)等手段其进行了表征。 相对比普通红磷,亚微米红磷更容易通过球磨与石墨复合,能有效提升石墨材料的储锂容量。 为红磷在锂离子电池负极材料上的应用提供了一种思路。 在少量添加红磷的条件下,当红磷质量分数为3%时smRP/G表现最佳(3%smRP/G)。 在100 mA/g电流密度下展示出了1417 mA·h/g的首次放电容量,首次库伦效率67.4%。 并在循环200圈后依然保持着700 mA·h/g的可逆循环容量。  相似文献   

6.
通过水热法获得了多孔纳米结构的红磷,其中水热处理24 h所得的红磷(H-RP24h)具有最高的光催化活性,光氧化罗丹明B(RhB)和光还原Cr(Ⅵ)的速率常数分别是9.2×10^-2和3.4×10^-2 min^-1,是商业红磷的23和26倍。进一步研究发现水热处理减小了红磷的尺寸、增强了光响应、提高了光生电子和空穴(h^+)的分离,从而提高了它的光催化活性。通过自由基捕获实验发现在光降解反应过程中起主要作用的活性物种是h+和超氧自由基。  相似文献   

7.
水滑石的插层及其选择性红外吸收性能   总被引:8,自引:0,他引:8  
矫庆泽  赵芸  谢晖  D.G.Evans  段雪 《应用化学》2002,19(10):1011-0
离子交换;水滑石的插层及其选择性红外吸收性能  相似文献   

8.
提出了用红外吸收法测三氧化钨中的硫 ,试验了称样量、助熔剂对硫释放的影响  相似文献   

9.
沉淀二氧化硅消光剂的制备研究   总被引:1,自引:0,他引:1  
涂料中的消光剂是一类能够改变涂膜表面光学性能的助剂。这类助剂能够在涂膜表面产生预期微粗糙度,使涂膜的光泽显著降低,给人一种古朴典雅的感觉。近几年来,我国的涂料工业方兴未艾,涂料总产量也跃居世界的前列。在这期间高光泽的亮光涂料以其色泽鲜艳、明亮等优点深受消费者的喜爱,并在相当长的时间内一统着涂料市场[1]。但是,随着人们生活水平的不断提高,一方面消费者感觉到了高光泽的亮光涂料成膜后反光比较严重,对人的眼睛有害;另一方面消费者的审美观念越来越倾向于休闲、时尚和个性化。这些因素就导致了人们对具有柔和外观的低光泽涂…  相似文献   

10.
将有机分子中的C和H、C和C、C和O、C和N间化学键的红外伸缩振动吸收峰位与MNDO法计算的原子对作用能相比较,找到了很好的相关性,并用最小二乘法拟合得到各自的回归线和回归方程,其相关系数均达到0.97以上。运用二者相关性规律定量地解释了有机分子中C-H、C-C、C=C、C≡C、C-O、C=O、C-N、C=N、C≡N键的伸缩振动吸收峰移动的影响因素,如不饱和性、诱导、中介、共轭、环张力等。  相似文献   

11.
The extinction coefficient of a collection of polyolefin foams was investigated experimentally and theoretically. Transmittance spectra were measured with Fourier transform infrared spectroscopy (FTIR) for samples of various thicknesses and different chemical compositions, densities, colors and structural characteristics. The extinction coefficients were then calculated by applying Beer's law. The results showed that the extinction coefficient decreased with the mean cell size and that this was the main structural parameter influencing the extinction coefficient of the foams under study. The experimental results agreed well with the Glicksman model. Moreover, the total thermal conductivity was calculated in terms of the Rosseland equation with an accuracy of 5%. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1608–1617, 2005  相似文献   

12.
A series of self-healable polyurethane (SHPU)/modified graphene (MG) nanocomposites were synthesized from poly(tetramethylene glycol) (PTMG) and 4,4′-methylene diphenyl diisocyanate (MDI) with minute amounts (0–1 wt%) of MG which was chemically modified graphene oxide (GO) with phenyl isocyanate and reduced in the presence of phenylhydrazine.  相似文献   

13.
采用气相色谱-质谱(GC-MS)联用技术,根据汽油原样中的特征成分,对未加入和分别加入汽油燃油精、海龙燃油宝的汽油燃烧烟尘进行对比分析.结果表明,汽油燃油精的加入会使汽油燃烧烟尘中各类特征成分的百分含量有所变化,但对谱图和特征成分的影响较小;而海龙燃油宝的加入对汽油燃烧烟尘的谱图、特征成分及其个数、各类特征成分的百分含量均产生较大影响.结果为火灾物证鉴定提供一定的参考依据.  相似文献   

14.
原子吸收光谱法测定香烟烟气中重金属的含量   总被引:15,自引:2,他引:15  
用原子吸收、荧光光谱法测定了不同品种香烟烟气的水吸收液中铅(Pb)、镉(Cd)、铬(Cr)、汞(Hg)的含量,并用等离子体发射光谱法进行比较测定。结果表明,原子吸收光谱法具有灵敏度高、干扰小、快捷的优点。方法回收率为98%~100%,相对标准偏差小于5.0%。实际样品测定结果令人满意。  相似文献   

15.
为测定血糯米中Fe、Zn、Mn微量元素含量,用V(HNO3) +V(HClO4) =4+1消解样品,火焰原子吸收光谱法测定.结果表明,血糯米中Fe、Zn、Mn的含量分别为:41.95、31.04、18.98μg/g,方法回收率在97.0%~104.2%之间,RSD≤4.1,该法准确度和精密度较高.可见血糯米中人体必需微...  相似文献   

16.
A significant increase in the stretching band intensity of trichloromethane in IR spectra of its solutions in acetone with increasing acetone mole fraction indicates the formation of hydrogen bonds between their molecules. The integral absorption coefficient (α) of this vibration is calculated. Experimental values of α are approximated by a theoretical dependence using the nonlinear least-squares method; association parameters are obtained. The relative volume fractions of H-bonded and free trichloromethane molecules are calculated depending on the total trichloromethane volume fraction in solution. The structure of the H-bonded associate is determined by quantum chemical calculations.  相似文献   

17.
Cinnamic acid (CA) was covalently attached to nonionic surfactants by condensation reaction. The mass and the molar extinction coefficient of CA residue of each conjugate did not markedly deviate from those of free CA, indicating CA could absorb the UV light after being conjugated to the surfactants. When the concentration of the conjugates in aqueous phase was 0.1% and 1.0%, mineral oil could readily be emulsified by polyoxyehtylene(20) cetyl ether–CA conjugate (CE20–CA), polyoxyethylene(20) oleyl ether–CA conjugate (OE20–CA), and polyoxyehtylene(20) sorbitan monolaurate–CA conjugate (Tween 20–CA). The extinction coefficients of the surfactant–CA conjugates contained in O/W emulsion did not markedly deviate from those of the conjugates dissolved in water, suggesting that the conjugate could maintain their extinction coefficients when they coexisted with oil droplets. According to the result of 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, the viability of cell (BALB/c 3T3 clone A31) was greater than 80% for all the surfactant–CA conjugates tested when the conjugate concentration was 0.2%. It is believed that CE20–CA, OE20–CA, and Tween 20–CA could be used as an emulsifier which absorbs UV light effectively.  相似文献   

18.
掺硼p型非晶硅薄膜的制备及光学性能的表征   总被引:1,自引:0,他引:1  
以高氢稀释的硅烷(SiH4 )为反应气体,硼烷(B2H6)为掺杂气体,利用RF-PECVD方法,在玻璃衬底上制备出掺硼的氢化非晶硅(a-Si:H)薄膜,研究了硼掺杂量对氢化非晶硅(a-Si:H)薄膜的光学性能的影响.利用NKD-7000 W光学薄膜分析系统测试薄膜的透射谱和反射谱,并利用该系统的软件拟合得出薄膜的折射率、消光系数、吸收系数等光学性能参数,利用Tauc法计算掺硼的非晶硅薄膜的光学带隙.实验结果表明,随着硼掺杂量的增加,掺杂非晶硅薄膜样品在同一波长处的折射率先增大后减小,而且每一样品均随着入射光波长的增加而减小,在波长500 nm处的折射率均达到4.3以上;薄膜的消光系数和吸收系数随着硼掺杂量的增大而增大,在500 nm处的吸收系数可高达1.5×105cm-1.在实验的硼掺杂范围内,光学带隙从1.81 eV变化到1.71 eV.  相似文献   

19.

To reduce the smoke release of poly(vinyl chloride) (PVC) during burning, layered double hydroxides (LDHs) and zinc oxide (ZnO) powders were used to modify the polymer. The results indicated that the addition of LDHs‐ZnO had a significant effect on smoke suppression. The limiting oxygen index (LOI) reached a maximum value and the smoke density rank (SDR) exhibited a minimum value when the weight percentages of LDHs and ZnO in PVC were 3% and 2%, respectively. Thermal stabilities of the modified PVC and degradation products were investigated by means of thermogravimetry and pyrolysis‐gas chromatography‐mass spectra (Py‐GC‐MS). The LDHs‐ZnO obviously accelerated the decomposition of PVC to release hydrogen chloride, and the decomposed PVC consequently produced the trans‐conjugated polyene sequences, which easily formed crosslinked structures. However, a cyclization reaction in PVC chain without the additives produced aromatic compounds such as benzene, toluene, and naphthalene at 350°C. Even though, an amount of aromatic compounds was released from the PVC modified with LDHs‐ZnO at the temperature of 600°C, the content of the decomposed products is relatively lower compared to unmodified PVC.  相似文献   

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