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101.
The adverse impacts of climate change are widely recognized as well as the importance of the mitigation of carbon dioxide (CO2). Battery driven vehicles are expected to have a bright future, since GHG emissions can be reduced. Lithium-ion (Li-ion) batteries appear to be the most promising, due to their high energy density. Recently, the discussion concerning adequate lithium carbonate (Li2CO3) resources is resolved. The current challenge is the needed increase in flow rate of Li2CO3 into society to foresee in forecasted demand. This research determines ten factors which influence the availability of Li-ion batteries for the EU27 in the coming decades. They are used in a system dynamics analysis. The results of this research show that undersupply can be expected in the EU27 until 2045 somewhere between 0.5 Mt and 2.8 Mt. Substitution of Li2CO3 in other end-use markets and recycling can relieve the strain on Li2CO3 supply to some extent. In 2050, 20% of the vehicle fleet in the EU27 can be battery electric vehicles (BEVs). The lack of resources in the EU27 and the geographical distribution of lithium in politically sensitive areas suggest that the shares of lithium available for the EU27 will be less than assumed in this research. The increase in flow rate shows to be the bottle-neck for a transition to (partly) battery driven vehicles in the EU27, at least when Li-ion batteries are used. Focusing on large-scale application of BEVs with Li-ion batteries in order to substantially mitigate CO2 emissions in transport is a futile campaign. 相似文献
102.
Congenital cystic adenomatoid malformation of the lung can be detected with antenatal ultrasound as hyperechogenic areas in the fetal chest. Associated extrapulmonary malformations as well as chromosomal aberrations are described as very rare. We present a case report of a fetus in the 23rd week of gestation who showed in the course of a routine ultrasound screening a large number of malformations: holoprosencephaly, arrhinencephaly, cleft palate, CCAM type III of the right inferior pulmonary lobe, ventricular septal defect and bilateral clubfeet. Chromosome analysis confirmed the suspicion of trisomy 13. The present case shows how important it is—even with malformations that are rarely accompanied by associated anomalies and which have a very good prognosis—to carry out a directed diagnosis including a fetal karyotyping. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
103.
104.
105.
测定了贵州高原喀斯特石漠化小流域内5种灌木叶片δ13C值的季节变化,旨在探讨季节及石漠化等级对植物叶片δ13C值的影响。结果表明:不同季节间植物叶片δ13C值呈显著差异,生长初期(4月)叶片的δ13C值显著高于生长中后期(7月、9月及12月);5种灌木种种间差异显著,火棘的叶片δ13C值最负,荚蒾的叶片δ13C值最正,粉枝莓,鼠李和竹叶椒的叶片δ13C值居中;7月不同石漠化等级间植物叶片δ13C值存在显著差异,而在其余月份(即4月、9月及12月)不同石漠化等级间植物叶片δ13C值不存在显著差异,但基本呈现无、轻度石漠化植物叶片小于中度石漠化植物叶片δ13C值的格局;整个生长季中,叶片δ13C值与土壤含水量的相关关系研究表明大多数种在大多数时间随土壤水分的减少其δ13C值增高。 相似文献
106.
The adsorption and desorption characteristics of Al3+ to/from humic acids at di erent pH, ionic strength, and temperature were
studied by the C-25 glucosan-gel chromatography method. The results showed that the maximum adsorption amount (Qmax) and
adsorption constant (k) increased, whereas, the absolute value of standard thermodynamic molar free energy change ( G0
m) decreased
with the increase of pH at constant ionic strength and temperature. With ionic strength increasing from 0 to 0.15 mol/L, Qmax and k
increased and the absolute value of G0
m decreased at constant pH and temperature. High temperature was unfavorable for the adsorption
reaction, as indicated by the dramatic decrease of Qmax and the absolute value of G0
m with an increase in temperature. The standard
thermodynamic molar free energy change ( G0
m) and the standard thermodynamic enthalpy change ( H0m
) of the adsorption reaction
were both negative, suggesting that adsorption reaction was spontaneous and exothermic. The desorption rate of HA-Al3+ complex
accelerated with the decrease of pH, and a significant linear relationship could be obtained between pH and the desorption rates of Al3+
from humic acids. These results demonstrated that the Al3+ adsorption reaction was a “biphase” reaction, and adsorption occurred at
both the interior and exterior adsorption sites of humic acids. 相似文献
107.
Effects of low temperature on aluminum(III) hydrolysis: Theoretical and
experimental studies 总被引:1,自引:0,他引:1
In this study, the effects of low temperature on aluminum(III) (Al) hydrolysis were examined both theoretically and experimentally by constructing a solubility diagram for amorphous aluminum hydroxide (Al(OH)3(am)) and a distribution diagram of hydrolyzed Al species. First, thermodynamic data of Al species at 4 degrees C were calculated from that at 25 degrees C. A well confirmed polymeric Al species, AlO4Al12(OH)24(7+)(Al13), was involved in building the diagrams and, correspondingly, the non-linear simultaneous equations with 13 degrees were resolved. Secondly, polarized Zeeman atomic absorption spectrophotometry (AAS), 27Al nuclear magnetic resonance (NMR) spectroscopy, and ferron-based spectrophotometry were applied for constructing the practical diagrams. The results show that a decrease of temperature from 25 to 4 degrees C caused the Al(OH)3(am) boundary on the solubility diagram to shift toward the alkaline side by about 1.0 pH unit and the minimum solubility of Al(OH)3(am) to reduce by 1.0 log unit. The distribution diagram indicates that the monomeric Al, Al13, and solid-phase Al(OH)3 were alternately the predominant species with the increase of pH value during Al hydrolysis. At 25 degrees C, Al13 was the dominant species in a pH range of 4.0 to 4.5, whereas at 4 degrees C, All3 was the leading species in a pH range spaced from 4.5 to 6.3. The predominant species changed from the monomeric Al to the solid-phase Al(OH)3 over the range of 1.8 pH units at 4 degrees C in comparison with the range of 0.5 pH unit at 25 degrees C. 相似文献
108.
109.
Polyaluminum chloride was synthesized with a membrane reactor, and the process characteristics, membrane fouling and cleaning were investigated. 相似文献
110.
Pure nano-Al13 and aggregates at various concentrations were prepared to examine the particle size effect of coagulation with inorganic polymer fiocculant. The property and stability of various species formed were characterized using Infrared, 27Al-NMR,photo correlation spectroscopy (PCS), and Ferron assay. Results showed that concentration and temperature exhibited different roles on the stability of Al13. The quantity of Alb species analyzed by ferron assay in the initial aging period corresponded well with that of Al13, which has been confirmed in a dimension range of 1-2 nm by PCS. Al13 solutions at high concentrations (0.5-2.11 mol/L)were observed to undergo further aggregation with aging. The aggregates with a wide particle size distribution would contribute to the disappeared/decreased Al13 basis on the 27Al-NMR spectrum, whereas a part of Al13 would still remain as Alb. At low concentrations,Al13 solution was quite stable at normal temperature, but lost its stability quickly when heating to 90°C. 相似文献