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21.
Ionic liquids are largely used to leach metals from primary (ores) and secondary sources (end-of-life products). However, dry ionic liquids with a carboxylic function on the cation have not yet been used to leach metals at temperature above 100 °C and under atmospheric pressure. The ionic liquid betainium bis(trifluoromethylsulfonyl)imide, [Hbet][Tf2N], was used in the dry state to recover neodymium, dysprosium and cobalt from NdFeB magnets and NdFeB production scrap. The magnets and the scrap were crushed, milled and roasted before being leached above 100 °C. Recovery efficiencies below 10% and a lack of selectivity for all the parameters tested pointed to the importance of water in the dissolution process. The influence of the viscosity of the ionic liquid and the composition of the metal oxides after roasting was investigated as well. Although the dissolution of pure metal oxides was faster than the dissolution of the magnets, the low leaching efficiencies could not be attributed to the composition and crystal structure of the samples, since magnets roasted with the same protocol have already been successfully leached in the past, albeit in the presence of water. The role of water on the mass transfer and on the coordination of the metals was studied by viscometry and by spectroscopic methods, respectively. It is shown that for leaching of rare earths with [Hbet][Tf2N], the presence of ligands such as water is mandatory to saturate the first coordination sphere of the dissolved rare-earth ions. This paper provides new insights in the dissolution mechanism of metal oxides by [Hbet][Tf2N] at leaching temperatures higher than those typically used in hydrometallurgical leaching processes.Recovery of neodymium, dysprosium and cobalt from NdFeB magnets with the dry ionic liquid [Hbet][Tf2N] was investigated at 175 °C and atmospheric pressure. 相似文献
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Validating and implementing the use of an infusion pump for the administration of thawed hematopoietic progenitor cells—a single‐institution experience 下载免费PDF全文
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Philip Moons Koen Luyckx Corina Thomet Werner Budts Junko Enomoto Maayke A. Sluman Chun-Wei Lu Jamie L. Jackson Paul Khairy Stephen C. Cook Shanthi Chidambarathanu Luis Alday Katrine Eriksen Mikael Dellborg Malin Berghammer Bengt Johansson Andrew S. Mackie Samuel Menahem Adrienne H. Kovacs 《The Canadian journal of cardiology》2021,37(2):215-223
BackgroundWe compared physical functioning, mental health, and quality of life (QoL) of patients with different subtypes of congenital heart disease (CHD) in a large international sample and investigated the role of functional class in explaining the variance in outcomes across heart defects.MethodsIn the cross-sectional Assessment of Patterns of Patient-Reported Outcome in Adults with Congenital Heart Disease-International Study (APPROACH-IS), we enrolled 4028 adult patients with CHD from 15 countries. Diagnostic groups with at least 50 patients were included in these analyses, yielding a sample of 3538 patients (median age: 32 years; 52% women). Physical functioning, mental health, and QoL were measured with the SF-12 health status survey, Hospital Anxiety and Depression Scale (HADS), linear analog scale (LAS) and Satisfaction with Life Scale, respectively. Functional class was assessed using the patient-reported New York Heart Association (NYHA) class. Multivariable general linear mixed models were applied to assess the relationship between the type of CHD and patient-reported outcomes, adjusted for patient characteristics, and with country as random effect.ResultsPatients with coarctation of the aorta and those with isolated aortic valve disease reported the best physical functioning, mental health, and QoL. Patients with cyanotic heart disease or Eisenmenger syndrome had worst outcomes. The differences were statistically significant, above and beyond other patient characteristics. However, the explained variances were small (0.6% to 4.1%) and decreased further when functional status was added to the models (0.4% to 0.9%).ConclusionsSome types of CHD predict worse patient-reported outcomes. However, it appears that it is the functional status associated with the heart defect rather than the heart defect itself that shapes the outcomes. 相似文献
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Nicole K. Leibold Wolfgang Viechtbauer Liesbet Goossens Klara De Cort Eric J. Griez Inez Myin-Germeys Harry W.M. Steinbusch Daniël L.A. van den Hove Koen R.J. Schruers 《Biological psychology》2013
Inhaling carbon dioxide (CO2)-enriched air induces fear and panic symptoms resembling real-life panic attacks, the hallmark of panic disorder. The present study aimed to describe the emotional and cardiovascular effects evoked by inhaling CO2, taking shortcomings of previous studies into account. Healthy volunteers underwent a double inhalation of 0, 9, 17.5, and 35% CO2, according to a randomized, cross-over design. In addition to fear, discomfort, and panic symptom ratings, blood pressure and heart rate were continuously monitored. Results showed a dose-dependent increase in all self-reports. Systolic and diastolic blood pressure rose with increasing CO2 concentration, whereas heart rate results were less consistent. Diastolic blood pressure and heart rate variation correlated with fear and discomfort. Based on this relationship and the observation that the diastolic blood pressure most accurately mimicked the degree of self-reported emotions, it might serve as a putative biomarker to assess the CO2-reactivity in the future. 相似文献
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Kornelia Neveling Ilse Feenstra Christian Gilissen Lies H. Hoefsloot Erik‐Jan Kamsteeg Arjen R. Mensenkamp Richard J. T. Rodenburg Helger G. Yntema Liesbeth Spruijt Sascha Vermeer Tuula Rinne Koen L. van Gassen Danielle Bodmer Dorien Lugtenberg Rick de Reuver Wendy Buijsman Ronny C. Derks Nienke Wieskamp Bert van den Heuvel Marjolijn J.L. Ligtenberg Hannie Kremer David A. Koolen Bart P.C. van de Warrenburg Frans P.M. Cremers Carlo L.M. Marcelis Jan A.M. Smeitink Saskia B. Wortmann Wendy A.G. van Zelst‐Stams Joris A. Veltman Han G. Brunner Hans Scheffer Marcel R. Nelen 《Human mutation》2013,34(12):1721-1726
The advent of massive parallel sequencing is rapidly changing the strategies employed for the genetic diagnosis and research of rare diseases that involve a large number of genes. So far it is not clear whether these approaches perform significantly better than conventional single gene testing as requested by clinicians. The current yield of this traditional diagnostic approach depends on a complex of factors that include gene‐specific phenotype traits, and the relative frequency of the involvement of specific genes. To gauge the impact of the paradigm shift that is occurring in molecular diagnostics, we assessed traditional Sanger‐based sequencing (in 2011) and exome sequencing followed by targeted bioinformatics analysis (in 2012) for five different conditions that are highly heterogeneous, and for which our center provides molecular diagnosis. We find that exome sequencing has a much higher diagnostic yield than Sanger sequencing for deafness, blindness, mitochondrial disease, and movement disorders. For microsatellite‐stable colorectal cancer, this was low under both strategies. Even if all genes that could have been ordered by physicians had been tested, the larger number of genes captured by the exome would still have led to a clearly superior diagnostic yield at a fraction of the cost. 相似文献