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1.
针对江西宜丰地区氧化锂质量分数<2.0%以下中低品位锂瓷土矿,研究了硫酸铵法提取碳酸锂技术路线。首先,利用二步焙烧工艺,有利于脱氟、提高锂浸出率,并且能够有效防止结窑现象发生。在浸出液除杂过程中,采用成矾除铝的方法将大量溶出的铝离子转变为KAl(SO4)2·12H2O、NH4Al(SO4)2·12H2O等有价值复盐,规避了传统石膏法产生的大量固废,有70%的铝离子被转变为矾盐晶体,同时带出大量的结晶水,减轻后续浓缩压力,对比传统的石膏法产生大量固废而言,其优点是显而易见的。碳化反应产品的XRD以及氧化锂含量分析表明,碳酸锂的纯度达到99%以上,全程锂收率为50%~60%。作为提锂实验对比,采用宜春414矿锂质量分数为4.0%的锂云母,由于414矿样中铝的相对含量更低,导致相同的除杂难度下得到的414矿样中浸出液锂离子浓度更高,浓缩倍数更小,414矿样的锂回收率更高。实验结果表明,中低品位锂瓷土提锂的工艺规律,通过适当改变参数,能够应用于难度更低的高品位的锂云母提锂过程。 相似文献
2.
Jianhua Huang Yanting Lu Jun Jin Zhihua Song Junjun Tang 《International Journal of Food Science & Technology》2021,56(10):5160-5167
A type of medium- and long-chain triacylglycerols (MLCT) rich in α-linolenic acid (ALA) was produced by chemical transesterification of medium-chain triacylglycerols (MCT) and flaxseed oils. Under the optimal substrate conditions of 60%, catalyst loading of 0.3% at 60 °C for 15 min, the product contained MLCT (74.06%), ALA (37.26%) and diacylglycerol (DAG) (11.25%). After that, changes in fatty acid (FA) composition, physicochemical properties and minor compounds after chemical transesterification (CTE) were investigated. The correlations analysis results of these factors on oxidative stability showed these factors could be divided into positive and negative groups. Although DAG appears to be beneficial in slowing down oil oxidation, it is critical to avoid its mass production because it would decrease MLCT. 相似文献
3.
Bertrand Matthäus Frank Pudel Yougui Chen Ayyapan Achary Usha Thiyam‐Holländer 《Journal of the American Oil Chemists' Society》2014,91(12):2065-2076
Canolol‐enriched extracts obtained from the extraction of fluidized bed treated canola meal with supercritical carbon dioxide were added to high‐oleic canola oil in different concentrations (200, 500 and 750 mg/kg). After 30 h of deep‐fat frying, oils fortified with canolol‐enriched extracts showed a two to three times better frying performance in comparison to the commonly used antioxidants (TBHQ, 200 mg/kg; rosemary extract, 40 and 200 mg/kg) and a control without antioxidants with regards to the formation of di‐ and polymer triacylglycerols, total polar compounds, secondary degradation products (anisidine value) and the iodine value. The canolol‐enriched extracts were also able to slow down the degradation of α‐ and γ‐tocopherol during frying resulting in significant amounts of tocopherols after 30 h of frying in comparison to the other oils. The influence of the canolol‐enriched extracts indicated strongly concentration‐dependent performance. With increasing concentration of the extract, the thermal stability of the fortified oil was improved. The only disadvantage of the addition of the extracts was an increase in the initial acid value, but within the frying time, only oil fortified with 750 mg canolol‐enriched extract/kg reached the limit given in different countries. 相似文献
4.
Li-Yan Pan Jia-Wei Liu Jin-cheng Mao Hai-Bin Wang 《Petroleum Science and Technology》2017,35(8):747-753
We, the Editor and the Publisher of Petroleum Science and Technology, have retracted the following article:Li-Yan Pan, Guo-Qing Feng, Jin-cheng Mao &; Hai-Bin Wang. “Oil soluble polymers as a viscosity-reducing agent for super heavy oil,” Petroleum Science and Technology, Volume 35, 2017, Issue 8, pages 747–753. doi:10.1080/10916466.2016.1273240We are now cognizant of the fact that the above article has substantial text-matching with the following article, to which no attribution was made:Jincheng Mao, Jiawei Liu, Haibin Wang, Xiaojiang Yang, Zhaoyang, Bo Yang &; Jinzhou Zhago. “Novel terpolymers as viscosity reducing agent for Tahe super heavy oil,” RSC Advances, Volume 7, 2017, Issue 31, pages 19257–19261.It is therefore not deemed to be an original contribution. We note the breach of warranties made by the authors with respect to originality and provenance, and of our policy on publishing ethics and integrity. We note that we received, peer-reviewed, accepted, and published the article in good faith based on these warranties, and censure this action.We have been informed in our decision-making by our policy on publishing ethics and integrity and the COPE guidelines on retractions. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as “Retracted”. 相似文献
5.
Man‐Li Zhao Jiang‐Ning Hu Xue‐Mei Zhu Hong‐Yan Li Jing Li Ya‐Wei Fan Ze‐Yuan Deng 《International Journal of Food Science & Technology》2014,49(2):453-459
Medium‐ and long‐chain triacylglycerols (MLCTs)–enriched structured lipid (SL) was synthesised through enzymatic interesterification from Cinnamomum camphora seed oil (CCSO) and camellia oil (CO) using Lipozyme RM IM from Rhizomucor miehei as a biocatalyst. Effects of different reaction conditions including substrate molar ratio, reaction time and reaction temperature were investigated. Results showed that 55.81% of total MLCT species (CCO/LaCL, LaCO/LCL, COO/OCO and LaOO/OLaO) was obtained in the interesterified product under the optimal conditions of substrate molar ratio of 1:1.5 (CCSO/CO) at 60 °C for 3 h. Thereafter, fatty acid profiles, tocopherol contents and physiochemical characteristics of the interesterified product and physical blend were comparatively investigated. The fatty acid composition of the interesterified product consisted of capric acid (26.33%), lauric acid (21.29%) and oleic acid (42.33%). It should be mentioned that the interesterified product contained predominantly oleic acid (88.69%) at Sn‐2 position, while MCFAs (68.05%) at Sn‐1,3 positions. Compared with physical blend, the reduction in tocopherol contents and changes of physiochemical characteristics occurred in SL. The smoke point of the interesterified product was much higher than that of the physical blend, which meant that such MLCTs‐enriched SL could be better for cooking purpose. 相似文献
6.
7.
间歇式电源的大规模发展及并网运行,在带来巨大经济效益的同时,也给电网中长期过程的频率稳定和有功平衡带来了巨大的影响。在间歇式电源机电暂态模型的基础上,对风电、光伏中长期自动发电控制(automatic generation control,AGC)子站进行建模,该模型可以接受调控中心AGC总站的调度命令,对间歇式电源进行功率调节。然后,利用甘肃电网的某典型日负荷、风速及光照曲线,深入分析了间歇式电源的波动特性及风光互补特性,验证了上述模型具有模拟中长期频率波动的能力。在此基础上,以平抑间歇式电源带来的联络线功率波动为目标,对机组出力计划、二次调频系统等控制策略的效果进行了分析。最后通过仿真计算论证了机组出力计划和AGC系统具有平抑间歇式电源功率波动性的作用。 相似文献
8.
New oligofunctional surfactants prepared from ethyl 2-aminododecanoate hydrochloride and positional isomers of aromatic acid
di- and trichlorides via amide bond formation, including also the monofunctional compound of comparison, have been synthesized. Surface properties
of the new compounds, in particular critical micelle concentration (CMC), surface tension at the CMC, effectiveness, and maximum
surface excess, were determined. Moreover, their effectiveness at flotation using the model mineral fluorite was studied.
We found that the surfactant parameters clearly depend on the number and position of the amphiphilic subunits attached to
the aromatic core. We also found that a bundling of amphiphilic subunits, as performed, is profitable in the flotation of
fluorite and that effects of preorganization due to the proximity and geometric grouping of the amphiphilic subunits are of
importance. As a rule, the more amphiphilic subunits are included in the surfactant structure, the more efficient is the collecting
agent, involving approximate enhancements of fluorite flotation by powers of 10 when going from mono- to bi- and trifunctional
surfactant analogs, respectively. Nevertheless, the surface properties of the newly synthesized surfactants do not directly
correlate with the flotation data, which makes relations between surfactant structure and efficiency of fluorite flotation
at the current stage of development difficult to determine. Future studies relating to this problem are suggested. 相似文献
9.
Preparation of sharp-melting hard palm midfraction and its use as hard butter in chocolate 总被引:1,自引:0,他引:1
Satsuki Hashimoto Toru Nezu Hiroshi Arakawa Tomonori Ito Shoji Maruzeni 《Journal of the American Oil Chemists' Society》2001,78(5):455-460
Preparation of hard palm midfractions (PMF) and its use as a cocoa butter equivalent ingredient were studied. Hard PMF is
obtained by multistep fractionation of palm oil involving dry fractionation (DF) and/or solvent fractionation (SF), usually
using hexane or acetone. From our experience, in acetone, a polar solvent, symmetrical 1,3-disaturated triacylglycerols tend
to selectively crystallize more than nonsymmetrical 1,2- or 2,3-disaturated triacylglycerols, making it suitable for obtaining
the solid midfraction. Unfortunately, triacylglycerols are very soluble in hexane, and temperatures at least 15 degrees lower
than those required for acetone must be used for equivalent crystal yields. On the other hand, DF is a less expensive and
safer process. Thus, multistep fractionation combining DF and SF using acetone was developed to achieve sufficient removal
of high-melting components, and further enrichment of 1,3-dipalmitoyl-2-oleoylglycerol and the hard PMF was obtained by triple-step
fractionation of palm olein or double-step fractionation of soft PMF. Compared to conventional hard PMF, this hard PMF had
a steeper melting curve and better snapping and sharp-melting qualities when used in chocolate. Heat resistance of the hard
PMF chocolate was similar to the conventional hard PMF chocolate, and its bloom resistance could be improved by adding polyglycerol
fatty acid esters. 相似文献
10.