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Cryo–EM structure of the CRY2 and CIB1 fragment complex provides insights into CIB1-mediated photosignaling

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Plant Communications 2023年第2期4卷 4-7页

作者： Yahui Hao Xue Zhang Yaqi Liu Miaolian Ma xiaowei huang Hongtao Liu Peng Zhang National Key Laboratory of Plant Molecular Genetics Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghaiChina University of Chinese Academy of Sciences BeijingChina

Dear Editor,Cryptochromes(CRYs)are blue-light photoreceptors that mediate various light responses in plants(Wang and Lin,2020;Wang et al.,2021).Two CRYs have been identified in Arabidopsis thaliana(At),AtCRY1 and AtCRY2,which mediate hypocotyl elongation and floral initiation(Ahmad and Cashmore,1993;Guo et al.,1998).CRYs are comprised of a conserved N-terminal photolyase-related(PHR)domain for chromophore FAD binding and a C-terminal domain(CCE)of variable length,and different plant CRYs have been found to exert overlapping biological functions(Lin et al.,1998;Rosenfeldt et al.,2008).

关键词： CRY1 CRY2 structure

Effects ofiron and temperature on solubility of light rare earth sulfates in multicomponent system of Fe2(SO4)3-H3PO4-H2SO4 synthetic solution

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Journal of Rare Earths 2020年第11期38卷 1243-1250,I0004页

作者： Shiliang Chen Longsheng Zhao Meng Wang Zongyu Feng Chao Xia Yang Xu xiaowei huang National Engineering Research Center for Rare Earth Materials GRINM Group Co.Ltd.Beijing 100088China Grirem Advanced Materials Co. Ltd.Beijing 100088China General Research Institute for Nonferrous Metals Beijing 100088China School of Metallurgy Northeastern UniversityShenyang 110819China

Numerous light rare earth elements(LREE)minerals containing Fe and P were processed by sulfuric acid roasting method,and the leaching solution mainly comprises LREE sulfate,Fe2(SO4)3,H3PO4,and H2SO4,however,the solubility data of LREE sulfates in this system is few.This work studies the solubility of LREE sulfates in independent LREE sulfate system RE2(SO4)3-Fe2(SO4)3-H3 PO4-H2SO4(RE=La,Ce,Pr or Nd)and mixed LREE sulfates system(La,Ce,Pr,Nd)2(SO4)3-Fe2(SO4)3-H3 PO4-H2SO4 at different temperature(25-65℃)and concentrations of Fe2(SO4)3(Fe2 O3,0-50.13 g/L),H2SO4(0.5 mol/L),and H3 PO4(P2 O5,20.34 g/L)based on the industrial operating condition at low liquid and solid ratio 2:1.The solubility of each LREE sulfate in the independent system(La2 O3,12.25-20.88 g/L;CeO2,41.93-62.35 g/L;Pr6 O11,37.34-56.69 g/L;Nd2 O3,26.60-37.63 g/L)is much higher than that of the mixed system(La2 O3,6.95-11.03 g/L;CeO2,10.63-21.51 g/L;Pr6 O11,11.56-20.36 g/L;Nd2 O3,12.36-19.79 g/L)under the same other conditions.The results also indicate that,in the two systems,both Fe and the temperature have negative effects on the solubility of LREE sulfates.That may occur due to the complication reactions between the complexes of RESO4+and Fe(SO4)2-.However,the influence degree of temperature and iron concentration on the LREE sulfates solubility varies in the two systems and among different LREE species.This research is of theoretical significance for optimizing the conditions of the sulfuric acid process for recovering the LREE from the mixed LREE bearing minerals as well as the single LREE containing secondary rare earth scraps.

关键词： Rare earth sulfate Solubility Ferric sulfate Sulfuric acid Phosphoric acid

Preparation of crystalline mixed rare earth carbonates by Mg(HCO3)2 precipitation method

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Journal of Rare Earths 2020年第3期38卷 292-298页

作者： Zonghe Yu Meng Wang Liangshi Wang Longsheng Zhao Zongyu Feng Xu Sun xiaowei huang National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous MetalsBeijing 100088China Grirem Advanced Materials Co. Ltd.Beijing 100088China

In acid treatment technology of Baotou mixed rare earth ore,large quantities of ammonia-nitrogen wastewater are produced in the step of ammonium bicarbonate precipitation to transform rare earth sulfate.In this paper,we adopted a green precipitant magnesium bicarbonate(Mg(HCO3)2) to substitute ammonium bicarbonate to eliminate ammonia-nitrogen pollution.The effects of n(HCO3^-):n(RE^3+),aging temperature and aging time on the crystallization using Mg(HCO3)2 precipitation method were investigated.The results indicate that the rare earths could be completely recovered when n(HCO3^-):n(RE^3+) is higher than 3.15:1.The crystal water content of rare earth carbonates is affected by the aging temperature.The precipitate has a bad filterability when the aging temperature is over 40℃.This can be attributed to the less crystallized water molecules of the hydrated rare earth carbonate precipitation.The mixed rare earth carbonates are prone to be crystalline,and have a good filterability at aging temperatures below 40℃.Meanwhile,the evolution mechanism of crystalline mixed rare earth carbonates is reasonably deduced,the amorphous rare earth carbonates are first dissolute and then recrystallized.Under the optimized aging conditions,the purity of the crystalline precipitate meets the requirements of the fine product standard(GB/T 16479-2008).The filtrated could be used to produce Mg(HCO3)2,thus to realize the recycling of magnesium sulfate.

关键词： Baotou mixed rare earth ore Magnesium bicarbonate Rare earth carbonates Ammonia-free Crystallization mechanism Filtrate recycling

Enhanced thermal stability of Ce_(0.33)Zr_(0.55)(LaNdY)_(0.12)O_(2) mixed oxides prepared by sulfate-aided coprecipitation method

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Journal of Rare Earths 2021年第5期39卷 587-595页

作者： Shilei Chen Yongke Hou Hao Wang Zheng Zhao Yongqi Zhang Juanyu Yang xiaowei huang National Engineering Research Center for Rare Earth Materials GRINM Group Co.Ltd.Beijing 100088China General Research Institute for Nonferrous Metals Beijing 100088China Guoke RE Advanced Materials Co. Ltd.Sanhe 065200China Rare Earth Functional Materials(Xiongan)Innovation Center Co. Ltd.Baoding 071700China

Ceria-zirconia based mixed oxides(CZs)have been applied in three-way catalysts(TWCs)for their high surface area and oxygen storage capacity(OSC).In this work,enhanced thermal stability of Ce_(0.33)Zr_(0.55)(LaNdY)_(0.12)O_(2)mixed oxides was realized via a facile and scalable approach,namely,sulfateaided coprecipitation method was labelled as CZ-S.Sulfate ion(SO_(4)^(2-))was added into raw solution in the form of sulfuric acid and acted as coordination agent.The control sample was prepared by conventional coprecipitation method without sulfuric acid added and labelled as CZ.The promotion effect of sulfate ion was analyzed systematically by X-ray diffraction(XRD),transmission electron microscopy(TEM),scanning electron microscopy(SEM),N_(2)adsorption-desorption,Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),OSC and hydrogen temperatureprogrammed reduction(H_(2)-TPR)analysis.XRD and high resolution TEM results reveal that CZ-S have homogeneous distributions of elements.TEM and SEM images show that fresh samples of CZ-S have narrower distributions of grain sizes and larger pore sizes than those of CZ.Through cross analysis of structure and morphology of CZ and CZ-S,we find that the introduction of sulfate ions results in uniform distributions of elements,narrows distributions of grain sizes,and enables the formation of secondary loose packing of sub-particles,which lead to enhanced thermal stability of the samples of CZ-S upon aging process at high temperature.After aging treatment at 1100℃for 10 h,aged samples of CZ-S present larger specific surface areas and pore volumes than the aged sample prepared by conventional coprecipitation method without sulfate ions added.Furthermore,the aged sample of CZ-S2(SO_(4)^(2-)/Zr=1)possesses the highest specific surface area of 21.9 m2/g and the biggest pore volume of 0.035 mL/g among all aged samples.

关键词： Ceria-zirconia based mixed oxides Sulfate-aided coprecipitation method Specific surface area Thermal stability Rare earths

Precipitation-dissolution behaviors of rare earth ions in H_3PO_4-Ca(H_2PO_4)_2 solutions

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Journal of Rare Earths 2019年第5期37卷 520-527页

作者： Shengxi Wu Longsheng Zhao Liangshi Wang xiaowei huang Yunhan Zhang Zongyu Feng Dali Cui National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous Metals School of Metallurgical and Ecological Engineering University of Science and Technology Beijing (USTB)

In order to achieve deeper understanding of rare earth elements(REEs) behaviors during phosphate rock processing with H_3PO_4. The solubility of REEs in Ca(H_2PO_4)_2-H_3PO_4 solutions with various concentrations of Ca(H_2PO_4)_2 at different temperatures were tested. The results demonstrate that REEs solubility decreases sharply with the increasing concentration of Ca(H_2PO_4)_2. Equations between [REE^(3+)] and [H^+],[H^+] and [Ca^(2+)] in Ca(H_2PO_4)_2-H_3PO_4 solutions were built based on the precipitation-dissolution equilibrium of rare earth phosphates and the ionization equilibrium of H_3PO_4. According to the equations, the decreasing mechanism of REEs solubility caused by elevated concentration of Ca(H_2PO_4)_2 was determined. The mechanism can be illustrated as that the elevated concentration of [H_2 PO_4^-] decreases the concentration of hydrogen ion by retarding the ionization process of H_3PO_4 and directly promotes the precipitation of rare earth phosphates. Furthermore, it can be easy deduced that similar effect would be caused by the other cation impurities(Fe^(3+), Al^(3+), etc.) on REEs solubility based on the mechanism. In addition, superimposed reduction effect on REEs solubility caused by the elevated concentration of Ca(H_2PO_4)_2 and the elevated temperature is found. This superimposed effect leads to a super low solubility of REEs in Ca(H_2PO_4)_2-H_3PO_4 solution. On the basis of the experimental study, outlooks and suggestions for further development of REEs recovery method are given.

关键词： Rare earth elements Phosphoric acid Monocalcium phosphate Solubility Temperature

Simultaneous recovery of rare earth elements and phosphorus from phosphate rock by phosphoric acid leaching and selective precipitation:Towards green process

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Journal of Rare Earths 2019年第6期37卷 652-658页

作者： Shengxi Wu Longsheng Zhao Liangshi Wang xiaowei huang Yunhan Zhang Zongyu Feng Dali Cui National Engineering Research Center for Rare Earth Materials GRINM Group Co.Ltd. School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

Phosphate rock has been considered as one of the potential promising resources for rare earth elements(REEs). But the cost issues and the technical challenges caused by the low content of REEs in ores did hinder the further development of REEs recovery technologies. In order to explore a green process for the recovery of REEs from phosphate rock, this study investigates the effects of phosphoric acid concentration, liquid-to-solid ratio(L/S ratio), leaching time and temperature on the leaching efficiencies of the major components from phosphate rock. A REEs recovery of 94.3% and a phosphorus recovery of 95.3%are achieved under the optimal conditions of attacking phosphate rock using 30%P_2 O_5 acid with an L/S ratio of 10:1 and a stirring speed of 250 r/min at 25 ℃ for 4 h. Then,the selective precipitation of REEs with 81.3% REEs recovery is realized by heating up the leaching solution from 25 to 90 ℃ and keeping for4 h. Thereafter, more than 95% phosphoric acid is recovered by H_2 SO_4 and high purity gypsum, more than95% CaSO_4(tested by XRF), is also produced at the same time. Ultimately, a green process that leaches phosphate rock with H_3 PO_4, selectively precipitates REEs from leaching solution by heating up, recovers H_3 PO_4 with H2 SO4 is proposed. Compared with REE recovery in traditional processes, this process owns the merits of simple operation, energy saving and minimum wastes.

关键词： Rare earth elements Phosphate rock Monocalcium phosphate Minimum

Green synthesis of ceria powders with special physical properties by carbon dioxide carbonization

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Journal of Rare Earths 2018年第10期36卷 1084-1089页

作者： Zongyu Feng xiaowei huang Meng Wang Xu Sun Yang Xu Qiannan Xue Shiliang Chen National Engineering Research Center of Rare Earth Materials General Research Institute for Non-ferrous Metals Grirem Advanced Materials Co. Ltd.

In order to improve the application values of Ce element, in this paper, rare earth chloride solution was used as raw material, the pH value was controlled by inorganic alkali, the ceria powders with special physical properties were prepared by carbon dioxide carbonization method. According to characterization of SEM, XRD, and TG-DSC, Ce（OH）3 prepared at pH = 7.5 exhibits smaller particle size than that prepared at other conditions. CeO2 precursor obtained by direct carbonization of Ce（OH）3 shows smaller particle size and narrow size distribution, CeO2 precursor forms at first by carbonization of Ce（OH）3 with the continuous addition of CO2 gas,and the chemical component is indicated to be Ce2 O（CO3）2·6 H2 O.Cubic phase CeO2 powders are obtained by calcined at 750 ℃ for 4 h. The mean particle size D（50） is0.941 μm, and particle size distribution is smaller than 1. The microscopic appearance is homogeneous,with a spherical-like shape and a grain size of 200-500 nm. The light quality characteristics of sedimentation volume and accumulation density are obviously better than those of carbonate precipitation products. The carbonization method can be used not only to obtain ultra-fine rare earth oxides with fine particle size, narrow distribution and high dispersion properties, but also to achieve the reuse of carbon dioxide greenhouse gas.

关键词： Carbon dioxide Carbonization method Ceria Green Special physical properties Rare earths

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熔喷机智能化控制系统的实践与应用

化工管理 2024年第5期 15-17页

作者：黄晓伟常州纺织服装职业技术学院江苏常州213164

文章针对熔喷机智能化控制系统控制流程长、工艺标准高、控制要求难等特点进行了详细的分析,并提出从物联网平台、PLC、变频器和伺服电机驱动自动化电气控制等系统进行优化设计,来满足生产过程实时和历史数据的采集与信息反馈,实现电气... 详细信息

文章针对熔喷机智能化控制系统控制流程长、工艺标准高、控制要求难等特点进行了详细的分析,并提出从物联网平台、PLC、变频器和伺服电机驱动自动化电气控制等系统进行优化设计,来满足生产过程实时和历史数据的采集与信息反馈,实现电气系统的高精度智能化控制应用措施。

关键词：熔喷机 PLC 物联网平台

基于多区域面积分方程的电大非均匀等离子体电磁特性高效计算方法

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电波科学学报 2024年第1期39卷 26-38页

作者：张慧雯陈宇浩黄晓伟盛新庆北京理工大学集成电路与电子学院射频技术与软件研究所

针对临近空间等离子体包覆目标的电磁特性快速准确评估这一迫切需求，本文运用基于多区域面积分方程(multi-region surface integral equation, MR-SIE)的全波数值计算方法，展现电大尺度、非均匀、高负介电常数等离子体的电磁散射与辐... 详细信息

针对临近空间等离子体包覆目标的电磁特性快速准确评估这一迫切需求，本文运用基于多区域面积分方程(multi-region surface integral equation, MR-SIE)的全波数值计算方法，展现电大尺度、非均匀、高负介电常数等离子体的电磁散射与辐射问题的仿真能力。首先，推导了非均匀等离子体的MR-SIE，使用间断伽辽金(discontinuous Galerkin, DG)方法提高对多区域复杂等离子体目标的建模与计算效率，研究了不同方程的数值性能；随后针对电子密度较大的高负介电常数区等离子体，运用一种简洁高效的截断策略，进一步提升了多层快速多极子算法的鲁棒性，避免了SIE计算高损耗介质内问题面临的数值不稳定性。数值实验表明，该方法在计算多种分割方式的多区域等离子体鞘套模型时具有良好的精度和效率，可用于大尺度复杂等离子体目标电磁辐射与散射特性的快速精确评估。

关键词：多区域目标面积分方程(MR-SIE) 等离子体鞘套负介电常数多层快速多极子算法(MLFMA) 间断伽辽金(DG)