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1.
本文分别对Na2O2与CO2反应、Na2O2与H2O的反应过程进行了探讨,得出Na2O2与H2O的反应实质是Na2O2先水解生成H2O2,H2O2再分解放出O2,并对教材中的实验进行了改进.  相似文献   

2.
袁丽霞 《化学教学》2005,(1):115-116
例1:CO和H2的混合气体3g,与足量的O2充分燃烧后,在150℃时将混合气体通过足量的Na2O2后,Na2O2增重的质量为( )  相似文献   

3.
H2O2在氰化法中辅助浸金的研究   总被引:1,自引:0,他引:1  
在氰化浸金中,如果添加适量的H2O2,就能加速金的溶解,降低NaCN的消耗,提高金的浸出率,并研究了H2O2辅助浸金的机理,特点及应用。  相似文献   

4.
近年来,H2O2被用来作为氧源是因为其合理的稳定性,迅速有效性,廉价经济和绿色环保(副产物只有水)。H2O2与廉价的、相对无毒的金属催化剂相结合的环氧化系统。在廉价生产和具体合成研究上具有很重要的意义。综述了简单金属盐类、金属卟啉类配合物和金属Salen类配合物以H2O2为氧化剂催化环氧化烯烃的研究进展。  相似文献   

5.
Na2O、Na2O2的性质——与H2O、CO2反应往往采取对比的方法学习,增补“Na2O、Na2O2与CO2反应”的实验,可增强实验的直观性、学习的趣味性,便于知识的掌握与巩固,弥补了中学教材(试验修订本*必修)中未安排“酸性氧化物与碱性氧化物反应”实验的不足,并可以作为指导学生开展研究性学习的素材。  相似文献   

6.
通过H2O2在强碱性溶液中产生红光的实验,计算得到了由激发态O2到基态O2所产生光子的波长,并从理论上对实验现象做了解释.  相似文献   

7.
“Na2O2 H2O”、“Na2O2 CO2”是中学化学中的二个基本反应,其中所包含的规律、方法均有较高的价值,本拟从三方面对其再认识,以期对培养学生的思维能力和计算能力有所帮助。  相似文献   

8.
略谈影响H2O2分解的因素   总被引:5,自引:0,他引:5  
本文主要是对H2O2的稳定性进行了一定程度的探讨.特别是对一些物质作为催化剂催化分解H2O2.以及在不同温度和碱度务件下H2O2的稳定性与无其它物质时的对比.从而得出一些有益于教学与科研的结论。  相似文献   

9.
文章对Na2O2与H2O反应实验进行了两个改进,趣味性和实验效果均很好。  相似文献   

10.
在中学化学教材中介绍了Na2O2与CO2的反应,但未涉及Na2O2能否与其他气态非金属氧化物反应的问题.同时,Na2O2与水及水蒸气反应,是否有过氧化氢生成也时有争论.现行各类模拟检测试卷尤其是2004年夏季全国高考的各类化学试卷中,多有涉及Na2O2与CO2、H2O以外的非金属氧化物如SO2反应及产物的实验探究性试题.为此,本文从热力学角度利用△G^O-来讨论Na2O2与H2O、CO2、SO2、NO2、NO、CO等气体反应的可能性.  相似文献   

11.
通过H2O2在强碱性溶液中产生红光的实验,计算得到了由激发态O2到基态O2所产生光子的波长,并从理论上对实验现象做了解释.  相似文献   

12.
The degradation of Microcystin-LR (MC-LR) in water by hydrogen peroxide assisted ultraviolet (UV/H2O2) process was investigated in this paper. The UV/H2O2 process appeared to be effective in removal of the MC-LR. MC-LR decomposition was primarily ascribed to production of strong and nonselective oxidant-hydroxyl radicals within the system. The intensity of UV radiation, initial concentration of MC-LR, MC-LR purity, dosages of H2O2, the initial solution pH, and anions present in water, to some extent, influenced the degradation rate of MC-LR. A modified pseudo-first-order kinetic model was developed to predict the removal efficiency under different experimental conditions.  相似文献   

13.
本文介绍了以大理石、过氧化氢为原料制备过氧化钙及测定过氧化钙含量的微型 化学实验.  相似文献   

14.
过氧化氢催化分解反应的实验数据处理   总被引:2,自引:0,他引:2  
介绍应用计算机软件Excel对H2O2催化分解反应速率常数的测定实验进行数据处理的基本方法,该处理方法准确、快速、简便,具有良好的实验教学功能和效果.  相似文献   

15.
This study probed the protective effect of recombinant Lactobacillus plantarum against hydrogen peroxide(H_2O_2)-induced oxidative stress in human umbilical vein endothelial cells(HUVECs). We constructed a new functional L. plantarum(NC8-p SIP409-alr-angiotensin-converting enzyme inhibitory peptide(ACEIP)) with a double-gene-labeled non-resistant screen as an expression vector. A 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2 H-tetrazolium bromide(MTT) colorimetric assay was carried out to determine the cell viability of HUVEC cells following pretreatment with NC8-p SIP409-alr-ACEIP. Flow cytometry(FCM) was used to determine the apoptosis rate of HUVEC cells. Cysteinyl aspartate specific proteinase(caspase)-3/8/9 activity was also assayed and western blotting was used to determine protein expression of B-cell lymphoma 2(Bcl-2), Bcl-2-associated X protein(Bax), inducible nitric oxide synthase(i NOS), nicotinamide adenine dinucleotide phosphate oxidase 2(gp91 phox), angiotensin II(Ang II), and angiotensin-converting enzyme 2(ACE2), as well as corresponding indicators of oxidative stress, such as reactive oxygen species(ROS), mitochondrial membrane potential(MMP), malondialdehyde(MDA),and superoxide dismutase(SOD). NC8-p SIP409-alr-ACEIP attenuated H_2O_2-induced cell death, as determined by the MTT assay. NC8-p SIP409-alr-ACEIP reduced apoptosis of HUVEC cells by FCM. In addition, compared to the positive control, the oxidative stress index of the H_2O_2-induced HUVEC(Hy-HUVEC), which was pretreated by NC8-p SIP409-alr-ACEIP, i NOS,gp91 phox, MDA, and ROS, was decreased obviously; SOD expression level was increased; caspase-3 or-9 was decreased, but caspase-8 did not change; Bcl-2/Bax ratio was increased; permeability changes of mitochondria were inhibited; and loss of transmembrane potential was prevented. Expression of the hypertension-related protein(Ang II protein) in HUVEC cells protected by NC8-p SIP409-alr-ACEIP decreased and expression of ACE2 protein increased. These plantarum results suggested that NC8-p SIP409-alr-ACEIP protects against H_2O_2-induced injury in HUVEC cells. The mechanism for this effect is related to enhancement of antioxidant capacity and apoptosis.  相似文献   

16.
Thermodynamic assessment in the ternary systems ZrO2 -CeO2 -Y2 O3, ZrO2 -CeO2 -Ce2 03 and the limiting binaries ZrO2 -Y2 O3, ZrO2 -CeO2, CeO2 -Y2 03, ZrO2 -Ce2O3, CeO2 -Ce2O3 as well as the modeling for oxides are reviewed comprehensively. Based on the recent estimations on the YO1.5-CeO2, ZrO2-CeO2 and ZrO2 -YO1.6 systems, isothermal sections at 1273 and 1 973 K of the ternary CeO2- ZrO2-YO1.5system are calculated. In the system of ZrO2-CeO2-Ce2O3, the complex relation between the nonstoichiometry (y) in CeO2-x, the composition of the ZrO2 -CeO2 solid solution and the oxygen partial pressure (Po2 ) for different ZrO2 containing solid solutions CexZr1-xO2-x. are evaluated from 1 473 to 1 773 K. The relation between the degree of Ce^+4 reduction to Ce.3 under different Po2 in the fluorite CeO2-xy and CexZr1-xOz-x solid solutions at different temperatures can be used as a guide in the development of functional ceramics.  相似文献   

17.
1IntroductionZrO2-containing ceramics receive extensive attentionbecause of their great i mportance in science and tech-nology[1,2].Zirconia doped with divalent or trivalentoxides has been proved to be an i mportant solid elec-trolyte,finding wide usage in oxygen sensors and fuelcells.It is also well known that Y2O3-stabilized tetra-gonal ZrO2polycrystals(Y-TZP)possess excellent me-chanical properties at roomtemperature,combining astrength higher than1000MPa and a toughness be-tween6MPa·…  相似文献   

18.
TiO2/Al2O3超声降解高浓度亚甲基蓝溶液性能研究   总被引:1,自引:0,他引:1  
采用溶胶-凝胶法在Al2O3表面负载TiO2制取TiO2/Al2O3催化剂,以亚甲基蓝为研究对象考察了TiO2/Al2O3催化剂的煅烧温度、亚甲基蓝反应初始浓度、介质酸度及TiO2/Al2O3催化剂用量对TiO2/Al2O3超声波降解脱色高浓度亚甲基蓝溶液的影响实验发现:煅烧温度对TiO2/Al2O3的活性有很大影响,从而对TiO2/Al2O3催化剂超声波降解脱色高浓度亚甲基蓝溶液有较大制约。煅烧温度在480℃时最佳;亚甲基蓝溶液的超声降解脱色速率随初始浓度的增大而降低;随介质酸度的增加,降解速率加快,中性条件下降解速率最低,当PH值呈碱性时,降解速率又有所提高。在TiO2/Al2O3催化剂作用下,超声波降解脱色高浓度亚甲基蓝溶液效果较好,能够有效的完成高浓度亚甲基蓝溶液的降解脱色。因此,TiO2/Al2O3催化剂超声波降解脱色高浓度亚甲基蓝溶液的方法,具有广阔的应用前景。  相似文献   

19.
本文根据无水碳酸钠与水作用生成结晶水合物的原理,以及H_2O_2和H_2O分子的某些相似性,研究了Na_2CO_3—H_2O_2复合物的制备方法和作为鱼塘增氧剂的性质测定。  相似文献   

20.
通过对化验室常用标准液稳定性较差的硫代硫酸钠标准溶液的分析,认为其标准液的有效期在2个月以内才能保证检验正常、检出的数据有效.  相似文献   

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