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1.
张彦英  吴长江 《农药》2001,40(3):15-16
用气相色谱法对丙硫酯进行分析,该方法简单,快速,准确,实用,标准偏差为0.38,变异系数为0.42%,回收率为99.2%-100.2%.  相似文献   

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杨晓妮 《陶瓷》2012,(12):18-20
通过钕-铝系列色料合成实验,分析不同配比及不同矿化剂等对色料呈色效果的影响,确定最佳工艺方法。对实验结果进行XRD及色度分析,确定其主晶相为钕酸铝,试样的明度均在70以上,色彩鲜艳亮丽。  相似文献   

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O2介质阻挡放电微等离子体制备O3   总被引:1,自引:0,他引:1       下载免费PDF全文
介质阻挡放电(DBD)是工业生产臭氧(O3)最有效的方法。研究以O2为原料气采用DBD微等离子体放电制备O3,研究了放电间距、放电长度、放电功率以及停留时间对产生O3的影响。此外,通过向正弦AC等离子体电源中叠加调制脉冲,探讨了脉冲占空比与调制频率对O3生成的影响。结果表明:O3浓度与DBD反应器的放电间距呈负相关,与O2的停留时间呈正相关,放电功率及有效放电长度对O3浓度的影响呈现火山形变化趋势。综合考虑O3浓度及能量产率确定了适宜的参数。与普通正弦交流电源相比,在其基础上叠加脉冲调制电源有利于O3的产生,而能量产率与占空比呈正相关,与调制频率呈负相关,据此确定了合适的占空比与调制频率。  相似文献   

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The purpose of this research is to evaluate the bactericidal capacity of different Advanced Oxidation Treatments (AOTs) based on ozone: ozone, ozone/hydrogen peroxide and ozone/titanium dioxide on a wild strain of Clostridium perfringens, a fecal bacterial indicator in drinking water. The dose of ozone consumed ranges from 0.6 mg L?1 min?1 to 5.13 mg L?1 min?1 depending on the process and on the sample. In the treatments combined with O3, H2O2 dose utilized is 0.04 mM and TiO2 dose, 1 g L?1. In order to evaluate the influence of natural organic matter and suspension solids over the disinfection rate, treatments are performed with two types of water – natural water from Ebro River (Zaragoza, Spain) and NaCl solution 0.9%. To achieve 4 log units of inactivation, 3.6 mg O3 L?1 is necessary in O3 treatment, 4.25 mg O3 L?1 in O3/TiO2 system and 2.7 mg O3 L?1 in O3/H2O2 after processing the natural water. In NaCl solution, to get the same inactivation, 0.42 mg O3 L?1 is necessary in O3 treatment, 1.15 mg O3 L?1 in O3/TiO2 system and 0.06 mg O3 L?1 in O3/H2O2 process. Even though the three treatments studied have a high bactericidal activity due to the number of surviving bacteria decreases to non-detectable levels, O3/H2O2 is the most effective system for eliminating C. perfringens cells in a lower contact time, followed by O3 and finally O3/TiO2 system.  相似文献   

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王芹珠  陈智 《化学试剂》1997,19(4):230-232
用硫脲,S-乙基异硫脲和胍与二烷基亚磷酸酯在四氯化碳的碱溶液中反应得到产率满意的磷酰化产物,它们的通式是:(RO)2PNHCNR′R″ONH和(RO)2PNHCOSEtNH2,其中:R=n-C4H9—,i-C4H9—,sec-C4H9—,n-C6H13—;R′=R″=H-,CH3CH2—。其中7种化合物未见文献报道。以上这些产物对金属离子的萃取作用,本文作了初步探索  相似文献   

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Single crystal In2O3 shows promise as a photoanode for the decomposition of water. Because of various difficulties in the preparation of the single crystal material, two simple techniques were developed for the preparation of polycrystalline In2O3 anodes. One method involves the thermal decomposition of the nitrate while the other utilizes the chemical vapour deposition technique. Voltammograms and photoresponse spectra of these anodes are compared to the single crystal material. Among other observations, it is noted that the quantum efficiencies of the thermally decomposed films are comparable to the single crystal material. It is also shown that the on-set potential can be shifted to more negative values by forming the mixed oxide In2O3/Y2O3.  相似文献   

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This paper studies the decomposition of formic, oxalic and maleic acids by O3, O3/catalyst, and O3/H2O2. The catalytic effect of Co2+, Ni2+, Cu2+, Mn2+, Zn2+, Cr3+, and Fe2+ ions is investigated. The results showed that—Co2+ and Mn2+ have the highest catalytic activity for the decomposition of oxalic acid while the catalytic effect of the studied ions is insignificant on the rate of decomposition of formic acid. Maleic acid decomposes by ozone into formic acid and glyoxylic acid, which subsequently oxidizes to oxalic acid. Though the studied ions have no effect on the decomposition of maleic acid, they have a significant effect on the produced oxalic and glyoxylic acids. In the presence of Cu2+ ions glyoxylic acid is mainly transformed into formic acid and traces of oxalic acid. In such case, a complete decomposition of maleic acid and its degradation products is achieved within 45 min. The results also show that combining H2O2 with O3 results in an increase in the rate of decomposition of oxalic acid. However, O3/H2O2 system is less active than O3/Co2+ or O3/Mn2+.  相似文献   

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The objective of the presented study was to test various oxidation processes with the aim being to reduce the concentration and toxicity of biocide wastewater from a Slovenian phytopharmaceutical factory. Laboratory-scale experiments employing two AOP processes – ozonation (O3) and peroxone (H2O2/O3) – were applied to reduce the concentration of the active components involved, i.e., methylisothiazolone (MI), chloromethylisothiazolone (CMI) and dichloromethylisothiazolone (DCMI). The reduction of the biocide wastewater load for the performed oxidation processes was evaluated using ecological parameters. The H2O2/O3 oxidation procedure using an O3 flow rate of 1g/L h, at a pH value of 10 and with the addition of 5 ml of H2O2 (0.3 M) proved to be the most effective treatment. The toxicity of the biocide-load wastewater with an initial EC50 = 0.38%, decreased to EC50 (24h) >100% and EC50 (48h) = 76%.  相似文献   

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近年来,由紫外线(UV)引起的肌肤伤害已逐渐被广泛认知,防晒产品的使用也因此逐渐增加.为了防御人体肌肤受到伤害,开发了一系列高效防护UVA/UVB的防晒产品,既便在高温高湿环境下使用,肤感依然良好.为达成对UVA/UVB的高效防护并兼具有舒适的肤感,有必要将作为紫外线吸收剂的无机颗粒均一分散在产品中.因此,开发出一个油包水包油(O/W/O)型多重乳化体系.在该体系内,疏水性无机微颗粒被分散于内层油相和外层油相中.涂抹于肌肤时,观察到微孔(未被无机颗粒覆盖的区域)于皮肤上的数量明显少于大多数使用W/O型乳化体系之防晒产品.这个O/W/O型多重乳化体系,不需在紫外线吸收剂中增加无机颗粒的含量,紫外线(UV)的防护效果就能增强;因此,能被用来制备兼具高效紫外线防护与良好肤感的防晒产品.描述的O/W/O型多重乳化体系,微孔少,可提供优越的UVA/UVB防护,防御人体肌肤受到伤害.  相似文献   

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A series of alumina aluminum borate (AAB) with various Al/B molar ratios were prepared by the coprecipitation method. The supported rhenium oxide catalysts with various contents of Re2O7 were also prepared by the impregnation method with perrhenic acid. The catalytic activity and stability of Re2O7/AAB catalysts for the reaction of propylene metathesis were tested in a fixed-bed microreactor. It was found that Re2O7/AAB is more active, stable and regenerable than Re2O7/Al2O3 for propylene metathesis. The optimum Al/B molar ratio was found to be in the range of 4–10.  相似文献   

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O Christmas tree     
《化学与工业》2013,77(12):42-45
  相似文献   

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半繁华艺术     
“哪个产业在过去10年发展最快?设计产业;哪个产业在将来50年发展潜力最大,设计产业;哪个产业正在深刻地改变人们的生活方式,设计产业。”这就是安基传媒公司出版人柳战辉创办大连O2纯氧设计书吧的初衷。  相似文献   

17.
Cerium oxide doped with oxides of rare earth elements is a multifunctional material, a wide range of uses which is associated with its unique physicochemical properties. Phase diagrams of multicomponent systems are the physicochemical basis for the creation of new materials with improved characteristics.In this work, phase equilibria in ternary CeO2–La2O3–Dy2O3 and binary La2O3–Dy2O3 systems in the whole concentration range were studied. No new phases have been identified in these systems. An isothermal section of the phase diagram of the CeO2–La2O3–Dy2O3 system at a temperature of 1500 °С is constructed. No new phases have been detected in the system. It was found that in the studied ternary system solid solutions are formed on the basis of (F) modification of CeO2 with structure of fluorite type, monoclinic (B), cubic (C) and hexagonal (A) modifications of Ln2O3.In the La2O3–Dy2O3 binary system (1500–1100 °С) three types of solid solutions are formed: based on hexagonal modification A-La2O3, monoclinic modification B-Dy2O3 and cubic modification C-Dy2O3 separated by two-phase fields (A+B) and (B+C), respectively. The boundaries of the regions of homogeneity of solid solutions based on A-La2O3 are determined by compositions containing 35–40, 20–25, 15–20 mol% Dy2O3 at 1500, 1250, 1100 °C, respectively. From the obtained data it follows that the solubility of Dy2O3 in the hexagonal modification of lanthanum oxide is 39 mol% at 1500 °C, 23 mol. % at 1250 °C and 16 mol% at 1100 °C. The limits of existence of solid solutions based on monoclinic B-modification are determined by compositions containing 30–35, 65–60 (1250 °С), 35–40, 55–60 (1100 °С) 40–45, 70–75 (1500 °C) mol% Dy2O3.In the studied system, with a decrease in temperature from 1500° to 1100°C, there is a decrease in the solubility of La2O3 in the crystal lattice of cubic solid solutions of C-type from 16 to 10 mol%.  相似文献   

18.
The limits of the glass-formation regions are established for the binary R′2−P2O5 and R″O5−P2O5 systems (R′=Li, Na, K: R″=Mg, Ca, Sr, Ba). It is shown that these boundaries closely correlate with those reported by other investigators despite the difference in the conditions in which these binary phosphate glasses were synthesized. The fact that all of the systems under study have about the same upper limits of glass-formation regions is attributed to the ratio R′2O(R′O): P2O5, which for the systems in question is 1.0–1.5 rather than the individual crystal-chemical characteristics of the R+ and R2+ cations. Translated from Steklo i Keramika, No. 2, pp. 13–15 February, 1997.  相似文献   

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Separation of phases was investigated in the hexagonal (rhombohedral) systems Al2O3−Cr2O3 and Al2O3−Cr2O3−Fe2O3. The binary system shows a miscibility gap with a Tc of 950°C; the miscibility gap for the ternary system was determined for a constant Cr2O3 content of 16.6 mol%. Dark field transmission electron microscopy of solid solutions annealed within the miscibility gap showed dark and light lamellas ∼50 to 200 Å thick. X-ray diffraction results for the solid solutions in the ternary system indicated that, in the early stages of annealing, broadening occurred only on (hkl) reflections where l≠0. There was no major change in the X-ray diffraction patterns of the annealed solid solutions in the binary system. Electron diffraction results indicated, however, that phase separation in both systems proceeded in the [001] direction. Solid solutions in the binary system separated very slowly; the separation could be enhanced hydrothermally. The mechanism of the separation of phases in both systems is spinodal and proceeds as follows: solid solution→intermediate modulated phase→equilibrium phases.  相似文献   

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