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1.
当我们在阳光下洗衣服时,盆里的肥皂或洗衣粉泡上会出现各种彩色花纹,并且随泡的大小变化,花纹的形状和颜色也不断的变化;炎热的夏天,雨过天晴,柏油路的积水面上浮着一层油膜会呈现出五颜六色;用手把两片无色透明的玻璃片捏在一起,阳光下也能看到彩色花纹.以上现象的产生,是因为光产生了薄膜干涉现象。  相似文献   
2.
为了研究洗衣粉溶液的合理使用浓度和温度,利用FD-NST-I型表面张力测定仪测量溶液表面张力系数,同时用pH计进行实验检测。结果表示:0.05%~0.10%的洗衣粉溶液在30.0~45.0℃时表面张力系数较小,更有利于洗净衣物,同时pH值较低,对手及被洗织物都不会产生损害,此区间取值与日常生活习惯相一致。  相似文献   
3.
结合高中新课程教科书,设计高中化学探究性实验——含磷洗衣粉对水藻生长的影响,通过实验原理、方法和具体实验过程得出结论,有效地促进了学生对化学知识的理解和掌握,培养学生实验设计和探究能力,达到知识、能力、情意目标。  相似文献   
4.
A novel approach for the design of phosphor-free single-chip white light-emitting diodes (LEDs) is proposed by employing InAIGaN irregular multiple quantum well (IMQW) structures. The electronic and optical properties of the designed InA1GaN IMQWs are analyzed in detail by fully considering the effects of strain, well-coupling, valence band-mixing, and quasi-bound states using the effective-mass Hamiltonian deduced from k. p theory. For comparison, three different types of InAIGaN IMQW structures with ultra-wide band spontaneous emission spectra are analyzed, and the results show that phosphor-free single-chip white light LEDs with more than 20Ohm emission band can be obtained using properly designed InAIGaN IMQW structures.  相似文献   
5.
氮配位的无磷聚合物负载钯配合物对Suzuki反应的催化性能   总被引:2,自引:0,他引:2  
制备了结构简单、氮配位的无磷钯配合物聚氯乙烯-二乙烯三胺钯, 利用XPS, TG, DTA和TEM等手段对其进行了表征. 热分析表明PVC-DETA-Pd在室温至220 ℃范围内有很好的热稳定性; TEM分析证实, 钯在PVC-DETA-Pd中分布比较均匀, 钯颗粒呈球形, 粒径在15 nm左右, 并测定了在不同温度、时间、溶剂和底物等条件下对Suzuki反应的催化性能及重复使用性能. 结果表明, 在没有惰性气体保护的情况下, 以NaHCO3作碱, 以DMF水溶液(体积比为2∶1)作溶剂, 在90 ℃时, 该配合物不仅对活性较高的碘代苯能够定量地催化, 对未活化的溴代苯也能定量地催化, 并且催化剂能够回收再利用8次以上.  相似文献   
6.
实际办案工作中,时常会涉及到对微量洗衣粉物证的检验鉴定。本文应用显微激光拉曼光谱分析技术对洗衣粉物证进行了检验研究。将所收集到的不同品牌的洗衣粉及同种品牌不同种类的洗衣粉样品采用显微激光拉曼光谱仪进行检测得到拉曼光谱图。通过谱图分析比较实现了对不同种类洗衣粉物证的快速无损区分检验。  相似文献   
7.
This paper presents an experimental and numerical study of the packing, compression, and caking behaviour of spray dried detergent(SDD) powders with a two-fold aim: an experimental process of observation and evaluation of the packing, compression and caking behaviour of SDD powders, and a numerical approach based on discrete element modelling(DEM). The mechanical properties, including the stress–strain response and the corresponding porosity change as a function of consolidation stress in a confined cylinder, the stress–strain response during unconfined shearing and the cake strength as a function of consolidation stress, were evaluated and compared for different SDD powders using an extended uniaxial tester(Edinburgh Powder Tester – EPT). The experiments using EPT showed excellent reproducibility in the measurement of packing, compression and caking behaviour and were therefore very useful for describing the handling characteristics of these powdered products including screening new products and different formulations. It was found that the sample with higher moisture had lower bulk porosity but higher compressibility and cake strength. The porosity, compressibility and cake strength were found to vary across different size fractions of the same sample. The larger sieve-cut samples had higher initial bulk porosity, compressibility and cake strength. It is revealed that moisture plays a significant role in packing, compression, and shearing behaviour of the powder. Three-dimensional DEM modelling using a recently developed elasto-plastic adhesive-frictional contact model showed that the contact model is able to capture the detergent behaviour reasonably well and can be used to model complex processes involving these powders.  相似文献   
8.
演示液体的表面张力和光的薄膜干涉需要肥皂水,我们往往就用一般的洗衣粉配制肥皂水,其肥皂膜的持续时间不过几秒钟,影响实验效果,为了使肥皂膜的时间延长,笔者通过反复实验,发现一种新的配方,用这种配方配制的肥皂水可以保存较长的时间,所成的肥皂膜能延续几分钟。  相似文献   
9.
针对洗衣粉的成分特性,采用硫酸消解样品,钼蓝光度法测定其磷含量。通过试验,确定了最佳分析条件。该方法的线性范围为1.20×10~(-2)~1.28 μg/mL,线性回归方程为A=0.786c-1.11×10~(-3),相关系数r=0.9998,加标回收率为96.6%~103%,相对标准偏差为1.2%~4.3%,检出限为0.3μg/25mL。该方法操作简单、快捷,适合环保监测工作的要求。  相似文献   
10.
端视等离子体原子发射光谱法测定无磷洗衣粉中磷   总被引:3,自引:0,他引:3  
利用端视等离子体原子发射光谱法测定了无磷洗衣粉的磷标准样品,探讨了基体元素钠对磷的干扰情况,对试验条件进行了优化,检出限为0.007μg·ml-1,RSD为2.9%~3.7%。方法简便快速,结果满意。  相似文献   
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