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111.
112.
Sen Dong Peng Gao Benhang Li Li Feng Yongze Liu Ziwen Du Liqiu Zhang 《Frontiers of Environmental Science & Engineering》2022,16(11):142
113.
114.
Du Wenbo Ma Xiaozhi Yuan Hongping Zhu Yue 《Environmental science and pollution research international》2022,29(39):58648-58663
Environmental Science and Pollution Research - The problems of data leakage and unreliable information transfer in the management process make sustainability management an inevitable need for... 相似文献
115.
Dan Du 《中国人口.资源与环境(英文版)》2017,15(3):226-238
The present study aims to better understand the relationship between energy intensity and its determinants including energy price, technological progress, economic structure, and energy mix using the autoregressive distributed lag(ARDL) bounds approach and vector error correction model technique. Based on China's time series over 1985-2014, the ARDL bounds approach yields empirical evidence that confirms the existence of long run relationship between energy price, technological progress, economic structure, energy mix, and energy intensity. The results show that technological progress is an important driver for the declining energy intensity in short and long run. Energy price has not been demonstrated as an important role in decreasing energy intensity in the short run. The high share of coal use in total energy use may be responsible for China's high energy intensity.However, the relative change in economic sectors plays a minor role in energy intensity reduction during the past years. In the long run, technological progress, energy mix and energy prices Granger cause energy intensity, but not vice versa except for the energy mix. 相似文献
116.
The effects of the annealing and partial substitution of Y for La on the structural and electrochemical properties of La1-xYxNi3.55Mno.4Alo.3Cro.75 (x = 0, 0.1 and 0.2) alloys were reported in the present work. The single-phased CaCu5-type structure was retained after La was partially substituted by Y. However, the increase of Y content leads to decrease of the lattice parameters and the unit-cell volume. The annealed Lao.9Yo.1Ni3.55Mno.4Alo.3Coo.75 alloys shows typical isometric microstructure, indicating that the composition segregation is improved by annealing. Y substitution for La in the alloys is effective to improve the electrochemical properties at both room temperature and high temperature. A critical substitution content of Y is found at x = 0.1. 相似文献
117.
A novel method was developed to suppress membrane fouling in submerged membrane bioreactors. The method is based on the dielectrophoretic (DEP) motion of particles in an inhomogeneous electrical field. Using a real sample of biomass as feed, the fouling-suppression performance using DEP with different electrical field intensities (60–160 V) and different frequencies (50–1000 Hz) was investigated. The fouling-suppression performance was found to relate closely with the intensity and frequency of the electrical field. A stronger electrical field was found to better recover the filtrate flux. This is because of a stronger DEP force acting on the biomass particles close to the membrane's surface. Above an intensity and frequency value of 130 V and 1 kHz, respectively the permeate flux was reduced due to an electrothermal effect. 相似文献
118.
概述了在辽宁大洼县田庄台抽水站地基处理工程中采用高压喷射注浆技术的实践经验,并介绍了从工程勘察、方案选择、设计、施工和检测的全过程。此项技术,经过长期沉降观测取得了良好的加固成果。 相似文献
119.
Du?ica Ili? Ivan S. Risti? Ljubi?a Nikoli? Mihajlo Stankovi? Goran Nikoli? Ljiljana Stanojevi? Vesna Nikoli? 《Journal of Polymers and the Environment》2012,20(1):80-87
In this work was described poly(d,l-lactide) microwave synthesis using tin(II) 2-ethylhexanoate initiated ring-opening polymerization. Polymerization was performed
at 100 °C with monomer to initiator molar ratio ([M]/[I]) of 5,000 in 30 min. The achieved number average molar mass of obtained
polymers (determined by gel permeation chromatography) was 102,320 g/mol, with the polydispersion index, Q, 2.80. Structural characterization was performed by FT-IR spectroscopy followed characteristic bands. For applicative purposes
the obtained polymer was purified during the procedure of microsphere preparation. Biodegradable microspheres prepared from
poly(d,l-lactide) have been widely studied in recent years and have become well established controlled drug delivery systems. In this
work microspheres were loaded with allyl thiosulfinate (allicin) and its transforments products (ajoene and vinyldithiine),
as pharmacological active substances. The morphology of the microspheres was analyzed using a scanning electron microscope.
Allicin was synthesized by acid oxidation of allyl disufide and purification of obtained products by liquid–liquid extraction
with diethyl ether. Obtained allicin, purity 73%, was transformed using microwave in acetone solution, at solvent boiling
temperature, for 5 min. For the quality and quantity analysis of allicin and its transformation process was used LC/MS chromatography.
(E)- and (Z)-ajoene were detected at retention time 3.1 and 3.3 min, respectively, whence 3-vynil-4H-1,2-dithiine and 2-vynil-4H-1,3-dithiine
were detected at 4.3 and 4.8 min, respectively. Retention time of allicin was 2.93 min, according to liquid chromatography
results. HPLC method was used for assessment of pharmaceutical substances (alicine and alicine transforments) releasing from
microspheres at room temperature in solutions with different pH (pH = 3 and pH = 8) for 24 h. 相似文献
120.