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1.
The invention of air conditioner (AC) has undoubtedly saved the world from the heat of summer. The development of AC is an important embodiment of continuous development and perfection of science and technology. This article explains the mechanism of freon pollution from the perspective of chemistry, and enumerates the important role of fluoride in daily life, to eliminates people's misunderstanding of fluorine element. The hardships of extracting fluorine reflect the chemists' research experience of collecting experience from failure and the scientific spirit of pursuing the truth. 相似文献
2.
臭氧层的化学破坏及其对策 总被引:1,自引:0,他引:1
臭氧层的化学破坏是人类的重大环境问题。本文对臭氧层的形成,作用,臭氧层破坏的后果,破坏臭氧层的物质及作用机制和保护臭氧层的对策作了探讨。 相似文献
3.
PreliminaryStudyonDestructionofFreon12byInductivelyCoupledPlasma——DevelopmentofICPTechnologyforWasteDestructionCHENDeng-yunan... 相似文献
4.
CoMo/TiO2-Al2O3催化剂的气相氟化改性 总被引:1,自引:0,他引:1
采用连续流动微型催化反应装置和氮气吸附等方法研究了气相预氟化和氟化铵溶液浸渍处理对CoMo/ TiO2-Al2O3噻吩加氢脱硫催化活性和物化性能的影响.通过对0.5 %~7 % (φ)各种氟里昂浓度和473~773 K各种温度及不同时间氟化处理的样品进行详细考察,发现在623 K下由含氟里昂1%(φ)的湿空气氟化的载体制备的催化剂样品,其噻吩的加氢脱硫的活性有明显改善,相对于非氟化样品、BY-2工业催化剂以及氟化铵溶液浸渍处理的催化剂活性提高20%~30%,且非常稳定.初步表征还表明,氟里昂气相加氟与氟盐溶液浸渍加氟相比较,有不破坏催化剂结构和不降低催化剂比表面积的优点. 相似文献
5.
讨论了应用高频电感耦合等离子体(ICP)消解氟里昂类废弃物的可行性及与国际先进技术的比较;应用低功率ICP系统进行氟里昂12的模拟消解,用GC-ECD方法对尾气中的残余成分和浓度进行分析,证明该系统对氟里昂12的处理效率高于99.9%,可以发展成为未来环保废物处理领域的一项新技术。 相似文献
6.
Karine Le Bris Roopa Pandharpurkar 《Journal of Quantitative Spectroscopy & Radiative Transfer》2011,112(8):1280-1285
The temperature dependence of the infrared absorption cross-sections of CFC-113 (1,1,2-trichlorotrifluoroethane) in a pure vapor phase has been recorded in the 600-1250 cm−1 spectral region using Fourier transform spectroscopy. Spectra at 0.05 cm−1 resolution have been used to derive the integrated band strengths of the five main absorption bands over a range of temperatures from 223 to 283 K. Our results show good agreement with previously published data. The new cross-sections will allow more accurate retrieval of atmospheric CFC-113 concentrations using infrared spectroscopic techniques. 相似文献
7.
G. P. Celata M. Cuno G. E. Farello A. Mariani
S. Solimo
《Experimental Thermal and Fluid Science》1991,4(6):737-746Experimental work was carried out to determine the flow pattern map in vertical heated pipes under steady-state and transient conditions, using Freon 12 in forced convective flow as working fluid and optical probes for the measurements Existing maps are based on adiabatic tests, steady-state conditions, and fluids different from Freon 12. Signals from optical probes (whose response is based on the variations in fluid refractive index) are analyzed in terms oflocal void fraction, using either the probability density function (PDF) or the ratio between the average and maximum values of the signal. From the analysis of the experimental measurements the definition of a map for annular and intermittent flow regimes was achieved. The map turned out to be in good agreement with the Weisman and Kang map developed in adiabatic, steady-state conditions Qualitative results for the transient conditions are also presented. 相似文献
8.
Dong Yang Jie Zhao Dr. Yanxia Zhao Prof. Yibo Lei Prof. Liping Cao Prof. Xiao‐Juan Yang Dr. Martin Davi Dr. Nader de Sousa Amadeu Prof. Dr. Christoph Janiak Dr. Zhibin Zhang Prof. Yao‐Yu Wang Prof. Biao Wu 《Angewandte Chemie (International ed. in English)》2015,54(30):8658-8661
Caged supramolecular systems are promising hosts for guest inclusion, separation, and stabilization. Well‐studied examples are mainly metal‐coordination‐based or covalent architectures. An anion‐coordination‐based cage that is capable of encapsulating halocarbon guests is reported for the first time. This A4L4‐type (A=anion) tetrahedral cage, [(PO4)4 L 4]12?, assembled from a C3‐symmetric tris(bisurea) ligand ( L ) and phosphate ion (PO43?), readily accommodates a series of quasi‐tetrahedral halocarbons, such as the Freon components CFCl3, CF2Cl2, CHFCl2, and C(CH3)F3, and chlorocarbons CH2Cl2, CHCl3, CCl4, C(CH3)Cl3, C(CH3)2Cl2, and C(CH3)3Cl. The guest encapsulation in the solid state is confirmed by crystal structures, while the host–guest interactions in solution were demonstrated by NMR techniques. 相似文献
10.
I. Yu. Shchapin V. I. Fel'dman V. N. Belevskii N. A. Donskaya N. D. Chuvylkin 《Russian Chemical Bulletin》1995,44(2):203-227
Thermal trasfomations of vinylcyclopropane (VCP) radical cations (RC) in X-ray irradiated frozen Freon matrices, CFCl2CF2Cl and CFCl3, were studed by ESR. Radical processes involving VCP.+ in very rarefied and moderately thickened gaseous VCP were simulated. Monomolecular cleavage of the cyclopropane ring ofgauche-VCP.+ (1) occurs to give the more thermally stable distonic radical cationdist(0.90)-C5H8
.+ (3). As the density of VCP increases RC3 adds at the double bond ofanti-VCP to give the distonic RC,.CH2CH2CHCH(CH2)3CHCHCH2
+ (5). Under the same conditions, the less thermally stableanti-VCP.+(2) undergoes monomolecular isomerization into RC1 or reacts withanti-VCP with the rearrangement (as in the condensed phase) to give its distonic form,dist(90.0)-C5H8
.+ (4). The MNDO-UHF method was adapted for quantum-chemical analysis of the constants of isotropic hyperfine coupling with1H and13C nuclei in neutral and charged hydrocabon radicals, since the standard version of this method inadequately reproduces the structural parameters of low-symmetry (C
1,C
s) paramagnetic species. A quantum-chemical analysis of the radiospectroscopic information and of the stereoelectronic control of thermal transformations of conformers of RC1 and2 into their structurally nonequivalent distonic forms3 and4, respectively, was carried out.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 212–235, February, 1995.This work was carried out with the financial support of the Russian Foundation for Basic Research (Project No. 93-03-04075). 相似文献