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1.
呋喃丹及其主要水解,代谢产物的检验 总被引:6,自引:0,他引:6
呋喃丹毒性较强,在动物体内和碱性介质下均易分解,该文研究了呋喃丹及其主要水解产物呋喃酚的提取方法和薄层色谱、气相色谱、气相色谱-质谱的检测方法,均获满意结果。当中毒后难以检出呋喃丹原体时,可以检测其水解产物呋喃酚认定中毒。 相似文献
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研究了不同浓度的F- 和Ce3 +对磷酸三钙 (Ca3 (PO4) 2 ,TCP)的水解过程和水解产物的影响。XRD及IR实验结果表明 ,TCP在NaF溶液中的水解产物为羟基磷灰石 (Ca1 0 (PO4) 6(OH) 2 ,HAP)和氟基磷灰石 (Ca1 0 (PO4) 6F2 ,FAP)的混合物。氟离子浓度越高 ,FAP的含量越多。TCP水解过程的pH值变化随氟离子的起始浓度不同而不同。氟离子浓度越高 ,pH值越低。TCP在CeCl3 溶液中的水解产物为铈取代的羟基磷灰石 (CexCa1 0 -y(PO4) 6-z(OH) 2 ,Ce HAP)。溶解实验表明 ,氟处理比铈处理更有效地增强了TCP水解产物的抗酸性。当F -浓度为 0 1%或Ce3 +浓度为 5× 10 - 2 %时 ,TCP水解产物的抗酸性最强 相似文献
4.
液质联用法研究活性黑5的水解产物 总被引:4,自引:0,他引:4
用高效液相色谱-质谱联用技术研究活性染料黑5及其水解产物的方法,考察了梯度洗脱对色谱分离及pH对其水解产物的影响;质谱辅助定性了其水解产物。结果表明:pH对活性黑5的水解过程影响非常显著;除了常规的水解产物,还检测到未知水解产物,推测可能在水解过程中还有其它的反应存在。活性染料黑5水解后的毒性升高,从染料及其水解产物的分子结构式来分析,这很可能和活性染料的活性基团变化有关。 相似文献
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CoO/CaTiO3的制备及其光催化分解水的性能 总被引:1,自引:0,他引:1
以碱金属化合物为矿化剂,以Ca(NO3)2和钛酸丁酯的水解产物TiO(OH)2为原料进行固态反应,制得CaTiO3粉末,再由浸渍法负载上CoO,制备出新型光催化分解水的催化剂CoO/CaTiO3. SEM, XRD和UV-Vis漫反射光谱表征结果显示,加入NaOH矿化剂可使固态反应完全,提高CaTiO3的结晶完整性. 适宜的NaOH用量为1.5%. 在400 W高压汞灯照射下,该催化剂在0.008 mol/L的Na2CO3溶液中分解水的产氢速率可达到468 μmol/(g·h). 相似文献
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A. V. Tvardovskii A. A. Fomkin Yu. I. Tarasevich I. G. Polyakova V. V. Serpinskii I. M. Guseva 《Russian Chemical Bulletin》1992,41(6):987-991
The changes in the thermodynamic functions of the sorbents were calculated for the first time from measurements of the deformations of vermiculite during the sorption of water vapor and adsorption-calorimetric data.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Institute of Colloid Chemistry and the Chemistry of Water, Academy of Sciences of the Ukraine, 252180 Kiev. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 6, pp. 1270–1275, June, 1992. 相似文献
12.
We have summarized results of many experimental investigations of the thermodynamics of ionization of H2O(liq.) from 0–300°C and from 1.0 atm to nearly 8000 atm. Results of these investigations (equilibrium constants, enthalpies of ionization, heat capacities, partial molal volumes, and compressibilities) have been used for a number of thermodynamic calculations. It is particularly noteworthy that it is possible to use thermal data from 0–145°C with an equilibrium constant for 25°C in calculating reasonably accurate equilibrium constants for temperatures as high as 300°C. Similarly, it is possible to use volumetric data that refer to 1.0 atm in calculating useful equilibrium constants that apply for pressures as high as 2000 atm.Much of the work reported here was done while the author was on leave at the University of Lethbridge. 相似文献
13.
W. Zielenkiewicz A. Zielenkiewicz K. L. Wierzchowski 《Journal of solution chemistry》1993,22(11):975-981
Enthalpies of solution in water H
sol
o
and enthalpies of sublimation H
sub
o
were determined for a number of crystalline derivatives of uracil: 1,6-dimethyluracil (m
2
1,6
Ura), 1,3,6-trimethyluracil (m
3
1,3,6
Ura), 6-ethyl-1,3-dimethyluracil (e6m
2
1,3
Ura), 6-propyl-1,3-dimethyluracil (pr6m
2
1,3
Ura) and 6-butyl-1,3-dimethyluracil (but6m
2
1,3
Ura). Standard enthalpies of hydration H
hydr
o
and standard enthalpies of interaction H
int
o
of the solutes with their hydration shells were calculated. The data obtained show that dependence of H
int
o
on the number of-CH2- groups of n-alkyl chain added upon substitution of diketopyrimidine ring is nonlinear. This finding is discussed in connection with results of X-ray diffraction structure determinations for the crystalline compounds. 相似文献
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以“质量守恒定律”为例,选取科学革命、科学问题、科学实验、归纳与重复、解释与预测等几个视角对科学课堂教学的各个环节进行了分析。通过分析,各环节中所蕴含的科学哲学内容得以显现,对科学课堂教学的认识更为全面,对科学本质的认识更加深刻。 相似文献
16.
Earl M. Woolley John O. Hill William K. Hannan Loren G. Hepler 《Journal of solution chemistry》1978,7(5):385-393
We have made calorimetric measurements of enthalpies of dilution of aqueous iodic acid and have used these results for evaluation of the standard enthalpy of ionization of HIO3(aq.). We have also made calorimetric measurements of enthalpies of addition of perchloric acid solution to aqueous solutions of KIO3, KNO3, NaIO3, and NaNO3 and have used these results to obtain further values for the standard enthalpy of ionization of HIO3(aq.). On the basis of all these results, we have selected Ho=–660±125 cal-mole–1 as the best available standard enthalpy of ionization of HIO3(aq.) at 298.15°K, compared to the previously accepted –2400 cal-mole–1. Using the best available K=0.157 for ionization, we also obtain Go=1097 cal-mole–1 and So=–5.9 cal-oK–1-mole–1 for ionization of HIO3(aq) at 298.15°K.On study leave from Department of Inorganic and Analytical Chemistry, LaTrobe University, Bundoora, Victoria, 3083, Australia, to University of Lethbridge.On study leave from Department of Chemistry, University of Wollongong, Wollongong, N.S.W. 2500, Australia, to University of Lethbridge. 相似文献
17.
T. P. Chusova L. N. Zelenina Yu. G. Stenin Z. I. Semenova V. A. Titov 《Russian Chemical Bulletin》2007,56(7):1313-1317
The unsaturated and saturated pressures of gallium trichloride vapor were measured by the static method with membrane-gauge
manometers in wide pressure (0.2–760 Torr) and temperature (313–1071 K) intervals. Scanning calorimetry was used to determine
the thermodynamic characteristics of GaCl3 fusion. The thermodynamic characteristics were obtained for sublimation, fusion, vaporization, and association in the vapor
of GaCl3 molecules. The enthalpies of formation and the absolute entropies of GaCl3 in the liquid and gaseous phases and Ga2Cl6 in the gaseous phase were calculated using literature data.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1266–1269, July, 2007. 相似文献
18.
离子反应发生条件中的“放出气体”,与其他资料中对生成物的描述不一致,也与有关反应事实不符。“放出气体”的出现,使教材中对气体生成物的描述时此时彼,没有时序性、规律性。对其与化学反应的关系及其与“生成气体”的区别进行了论述,并提出了修改的建议。 相似文献
19.
Anna Zielenkiewicz Wojciech Zielenkiewicz Leonid F. Sukhodub Olga T. Glukhova Alexander B. Teplitsky Kazimierz L. Wierzchowski 《Journal of solution chemistry》1984,13(11):757-765
Enthalpies of solution in water, H
sol
o
, and of sublimation, H
subl
o
, were determined experimentally for a number of crystalline N-methyl adenines: m6Ade, m
2
6,6
Ade, m9Ade, m
2
6,9
Ade, and m
3
6,6,9
Ade. Derived standard enthalpies of hydration H
hydr
o
, were corrected for the calculated cavity terms H
cav
o
to yield enthalpies of interaction H
int
o
of the solutes with their hydration shells. The increments of H
int
o
per unit area of the water-accessible molecular surface S
B
, H
int
o
(CH3)/S
B
(CH3), for the particular methyl groups: is considered to be the net effect of the gain in the energy resulting from van der Waals' interactions and of the loss in the energy due to polar interactions upon methyl substitution. It proved to vary somewhat numerically in agreement with the theoretically predicted hydration schemes of adenine. Comparison of H
int
o
/S
B
value for adenine with those previously determined for uracil and thymine indicates that the aminopurine moiety is less hydrated than the diketopyrimidine ring. 相似文献
20.
R. M. Lazorenko-Manevich A. N. Podobaev L. A. Sokolova 《Russian Journal of Electrochemistry》2007,43(1):42-50
Based on the model of spatial separation of the dissolution and passivation of hydrophilic metals, the effect of strong specific adsorption of anions on the shape of curves for the relaxation of anodic current of metals in acid solutions after switching an anodic activation pulse off is considered by using iron as an example. 相似文献