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The tectonic evolution of the southwestern Yangtze Block during the Early Neoproterozoic period is still controversial because of the limited quantities of 1 000–860 Ma magmatic rocks. In this study, our new LA-ICP-MS zircon U-Pb dating results demonstrate that the Yanbian granodiorites in the southwest Yangtze Block were emplaced at 894.6±7.4 Ma, representing the product of an 894 Ma magmatism. The Yanbian granodiorites are metaluminous to weak peraluminous with A/CNK values of 0.8–1.1, resembling I-type granitoids. They are characterized by right-inclined REE patterns with moderate to insignificant negative Eu anomalies (δEu=0.6–0.9). Their primitive mantle-normalized trace element patterns are characterized by depletion of Nb, Ta and Ti and weakly enrichment of Th. Considering the positive whole-rock eNd(t) (+5.8 to +6.8), we propose that these granodiorites originated from the partial melting of juvenile mafic lower crust. The Yanbian I-type granitoids have low Y and Nb contents similar to volcanic arc igneous rocks in the Y-Nb plot for tectonic discrimination. In conclusion, Early Neoproterozoic Yanbian granodiorites have generated in a compression setting in an active continental margin. Together with previous studies from the southwestern Yangtze Block, we suggest that the 894 Ma subduction-related Yanbian granodiorites represent the early stage of subduction at the southwestern margin of the Yangtze Block.

This work aims to freely translate an input face to an aging face with robust identity preservation, satisfying aging effect and authentic visual appearance. Witnessing the success of GAN in image synthesis, researchers employ GAN to address the problem of face aging synthesis. However, most GAN-based methods hold that the aging changing of all facial regions is equal, which ignores the fact that different facial regions have distinct aging speeds and aging patterns. To this end, we propose a novel Conditioned-Attention Normalization GAN (CAN-GAN) for age synthesis by leveraging the aging difference between two age groups to capture facial aging regions with different attention factors. In particular, a new Conditioned-Attention Normalization (CAN) layer is designed to enhance the aging-relevant information of face, while smoothing the aging-irrelevant information of face by attention map. Since different facial attributes contribute to the discrimination of age groups with divers degrees, we further present a Contribution-Aware Age Classifier (CAAC) that finely measures the importance of face vector’s elements in terms of the age classification. Qualitative and quantitative experiments on several commonly-used datasets show the advance of CAN-GAN compared with the other competitive methods.

We undertook U-Pb-Hf isotope testing of detrital zircons from Late Paleozoic sedimentary rocks in the Jilin Province, NE China, with the aim of constraining the tectonic evolution of eastern Central Asian Orogenic Belt. The age populations of the detrital zircons from the sandstone of the Jiefangcun Formation in the Songliao Block are ~2234, ~1782, ~1030–921, ~817, ~540, and ~381–254 Ma, whereas those of the zircons from the greywacke of the Permian Kedao Formation in the Songliao Block yield are ~2436, ~1905, ~1692, 1146–1170, ~554–498, and ~342–255 Ma. Combined Hf isotope characteristics, these ages reveal that: (1) rocks from the Jiefangcun and Kedao formations were deposited after 254 and 255 Ma, respectively; (2) these formations were sourced mainly from the Songliao Block and the Jiamus Terrane in the eastern CAOB and to a lesser amount, from the northern margin of the NCC; and (3) it appears that several remnants of ancient Precambrian basement occur adjacent to these Late Paleozoic strata that occur within the microcontinental blocks. Detrital zircons from the silty sandstone of the Miaoling Formation in the western margin of the Khanka Terrane yield peak age populations of 508–476, 463–396, and 348–258 Ma, having similar eHf(t) values to those obtained from zircons within the Jiamusi Terrane. These data indicate that (1) deposition of the Miaoling Formation in the western margin of the Khanka Terrane had started by 258 Ma, and (2) these sediments were sourced mainly from the Jiamusi Terrane and local magmatic rocks. The widespread occurrence of detrital zircons with ages of 480–550 Ma and positive eHf(t) values within the Late Paleozoic strata in the Songliao Block and the Jiamusi–Khanka Terrane, indicates that the amalgamation of these blocks took place during the middle stage of the Paleozoic, probably after the Silurian, prior to the Late Permian.

Characterizing atom/ion mobility in superionic materials is one of the most essential topics. In this work, we show that the copper ion mobility in a promising thermoelectric material Cu x AgSe y (x, y = 0.98, 1.02), can be significantly changed by modulating the element ratio, x/y. With 63 Cu NMR linewidth as a direct measure of the copper ion mobility, we observed distinguishable Cu ion mobility in the samples with different ratios even under ambient temperatures. This distinction was further evaluated in terms of correlation times and activation energy of copper diffusion. The contrast in ion mobility could be understood from the point of view of vacancy mediation. This work gives fruitful information for understanding ion dynamics and related topics.

A green and efficient liquid–liquid extraction system was developed for the separation of lithium isotopes by using hydrophobic ionic liquids (ILs = [C4,6,8,10mim]+[NTf2]−) as extraction organic phase and benzo-15-crown-5 (B15C5) as complexing agent. The maximum single-stage separation factor α of 6Li/7Li obtained in this study was 1.029 ± 0.001, indicating 6Li was enriched in ionic liquid phase while 7Li was concentrated in the aqueous phase. The lithium ion was extracted into the ionic liquid in the formation of 1:2 complex [Li+(B15C5)2]. The negative data of thermodynamic parameters (∆ H0 and ∆ G0) suggest that the extraction system was a spontaneous exothermic process. In addition, effective lithium isotopes separation factor and the extraction efficiency of lithium ions can be gained in the condition of lower temperature with softer counter anions in the novel extraction system.

A novel phosphonium ionic liquid (IL), tetrabutylphosphonium bis(2,4,4-trimethylpentyl)phosphinate([P 4444 ][BTMPP]), was prepared and characterized by NMR spectroscopy. The solvent extraction behavior of lithium from aqueous solution by this IL in toluene was investigated. The extraction behavior was carried out as a function of various parameters such as aqueous acidity, temperature and extractant concentration. The extraction efficiencies obtained in [P 4444 ][BTMPP] were compared with those observed in molecular extractant bis(2,4,4-trimethylpentyl) phosphinic acid (HBTMPP), from which the anion of the ionic liquid extractant was prepared. The extraction efficiency for extraction of lithium by [P 4444 ][BTMPP] was much higher than that for extraction by HBTMPP. The extracted species were ascertained from slop analysis method which indicated 1:1 (metal:ligand) ratio in the complex. In addition, the effects of thermodynamic parameters, the stripping of lithium from the ionic liquid, and the reusability of the phosphonium ionic liquid were studied in detail.

Extraction of Li+ ions from salt lake brine into an ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C2mim][NTf2]) mixed with tri-n-butyl was investigated. The extraction mechanism was been studied using UV–Vis spectroscopy From the temperature dependence data, the thermodynamic functions values (ΔG°, ΔH°, and ΔS°) were calculated. Furthermore, stripping of metals from ionic liquid phase to an aqueous phase by hydrochloric acid was accomplished.

Atomic-scale dynamics of a representative noble metal chalcogenide superionic conductor, stromeyerite (CuAgS), were examined by nuclear magnetic resonance (NMR) spectroscopy at various temperatures. Motional narrowing of 63 Cu NMR line width was found in its cubic phase, demonstrating copper ions start diffusing via a hopping process. Moreover, the absence of 63 Cu NMR signal in its orthorhombic or hexagonal phases was discussed, which could be well explained by copper ordering and reduced local symmetry at copper sites. The above NMR results are relevant for understanding its electron-crystal phonon-liquid behaviors and transient structure-transformation, which are associated with extremely low thermal conductivities and abnormal change of thermal power during superionic phase transition in this material.

Two non-fluorinated ionic liquids (ILs), namely tetrabutylammonium bis(2-ethylhexyl)-phosphate, [N4444][DEHP], and tetraoctylammonium bis(2-ethylhexyl)-phosphate, [N8888][DEHP], were synthesized and fully characterized by 1H and 13C NMR spectroscopy. These functionalized ILs were subsequently evaluated in terms of their ability to extract lithium ions from aqueous solution. The extraction efficiencies of these functionalized ILs for lithium ions were measured as a function of various extraction parameters, including aqueous acidity, temperature and extractant concentration. The extracted species were determined using a slope analysis method, which indicated that the ILs formed a 1:1 (metal:ligand) complex. Fourier transform infrared spectroscopy studies were conducted to better understand the nature of the extracted species. We also investigated the stripping of the lithium ions from the organic phase and the re-use of the ionic liquid in a subsequent extraction step.

In this paper, a novel liquid-liquid extraction system was investigated for the selective separation of lithium isotopes using ionic liquid (IL) and dichloroethane as extraction solvent and dibenzo-14-crown-4 (DB14C4) as extractant. Results showed that the separation performance of DB14C4 has been improved after the ILs were involved in the extraction process. The maximum single stage separation factor α for 6Li/7Li obtained in the present study was 1.021. The light lithium isotope 6Li and the heavy lithium isotope 7Li were concentrated in organic phase and solution phase, respectively. The order of the single stage separation factor obtained in different lithium salts was LiI > LiBr > LiClO4 > LiCl. From the temperature dependence data, the thermodynamic functions values of the lithium isotope exchange reaction were calculated.

A novel liquid–liquid extraction system was investigated for the selective separation of lithium isotopes using ionic liquids (ILs = [C 6,8,10,12 mim] + [PF 6 ] － ) as extraction solvent and benzo-15-crown-5 (B15C5) as extractant. The effects of the concentration of lithium salt, counter anion of lithium salt, initial pH of aqueous phase, and extraction temperature on the lithium isotopes separation were studied. The maximum single-stage separation factor α of 6 Li/ 7 Li obtained in the present study was 1.038 ± 0.002, indicating the lighter isotope 6 Li was enriched in organic phase while the heavier isotope 7 Li was concentrated in the aqueous phase. The formation of 2:1 complex Li(B15C5) 2 + in the IL phase was determined on the basis of slope analysis method. The large value of the free energy change (− G 0 = 77.87 J mol −1 ) indicated the high separation capability of the lithium isotopes by B15C5/30%CH 3 Cl-70% C 6 mimPF 6 mixture extraction system. Lithium in Li(B15C5) 2 + complex was stripped by 0.5 mol·L −1 HCl solution. The extraction system offers high efficiency, simplicity application prospect to separation lithium isotope separation from LiCl solution.

The key progress in the development of solar cells based on mixed organic-inorganic halide perovskite was reviewed. Perovskite solar cells (PSCs) have developed rapidly and achieved highest efficiency exceeding 20% in these years. The origin, working principle and fabrication technology of PSCs are stated, and several promising methods to realize the industrialization of the solar cell modules have been put forward. Meanwhile, two main problems existing in PSCs have been pointed out, hysteresis in the photocurrent density-voltage measurement and the instability of perovskite, which have impacted the application of PSCs seriously. Efforts and study in order to solve these problems are also listed. The fundamental mechanism still needs further investigation so as to improve the performance of PSCs and realize their large-scale application eventually.

Herein, the amine-functionalized MCM-41 mesoporous silica (denoted as MCM-41-NH2) was synthesized and applied to adsorption and recovery U(VI) ions from aqueous solutions. The results showed that the sorption of U(VI) on MCM-41-NH2 was strongly dependent on pH and ionic strength. The sorption was mainly dominated by outer-sphere surface complexation and the sorption equilibrium can be reached within 60 min. The maximum sorption capacity of MCM-41-NH2 for U(VI) was calculated to be 386.98 mg g−1 at pH 5.60, much higher than that of the other reported materials.

Separation among lithium ion and magnesium ion remains challenging. In this work, solvent extraction of lithium ions from the Mg(II)-containing salt lake brine into a commonly used ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([C 4 mim][NTf 2 ]) using the neutral phosphorus compound tri-n-butyl phosphate (TBP) as the extractant was investigated. The extraction behavior of lithium ions was investigated as a function of various parameters: acidity of the salt lake brine, dosage of ionic liquid and phase ratio. Under the optimal conditions, the single extraction efficiency of lithium was 92.37%, which indicated that it was an efficient extraction system for the recovery of lithium ions. Based on the study of thermodynamics, thermodynamic parameters of the lithium ion extraction reaction were obtained. The extracted species were ascertained from slope analysis method which indicated 1:1 (metal:ligand) ratio in the complex. UV–visible and Fourier transform infrared spectroscopy (FTIR) studies were also carried out to understand the nature of the extracted species.

Water molecules have been reported to cause the degradation of perovskite crystals by forming a hydrated intermediate structure and then lead iodide irreversibly. Here, the quality of fully crystallized perovskite films is found to be improved by spraying water vapor with an appropriate time. Moreover, this healing effect was found to be reversible and would disappear when the water molecules escaped. Through measuring the steady-state and time-resolved photoluminescence of perovskite film before and after water vapor spray, we found that water molecules can deactivate the nonradiative recombination centers due to hydrogen bonding with uncoordinated ions on the surface of perovskite film. Furthermore, by analyzing the capacitance of devices without and with water vapor spray, the healing or deactivation effect was clearly seen in the significantly decreased density of defect states. This work emphasized the effectiveness of hydroxyl to heal the defects due to dangling bonds on the material surface, and cl...

To examine the ionic migrations on atomic level in metal chalcogenide phonon glasses, 63Cu solid state nuclear magnetic resonance (NMR) spectroscopy was performed in an archetype CuAgSe compound. The observed characteristic motional narrowing effect in the superionic state provide clear evidence for the model of single ion-hopping instead of free-ion-like motion. We further find, for the first time, that thermal conductivity is strongly correlated with cation dynamics revealed by NMR within the range of temperatures investigated. This investigation provides better understanding how microscopic structure affects thermal transport properties which is of current interest in transition-metal chalcogenide based fast ion conductors.

This study used spectrometry to determine the spectral absorption of five types of mafic-ultramafic rocks from the Kaishantun ophiolite suite in Northeast China. Absorption peak wavelengths were determined for peridotite, diabase, basalt, pyroxenite, and gabbro. Glaucophane, actinolite, zoisite, and epidote absorption peaks were also measured, and these were used to distinguish such minerals from other associated minerals in ophiolite suite samples. Combined with their chemical compositions, the blueschist facies (glaucophane + epidote + chlorite) and greenschist facies (actinolite + epidote + chlorite) mineral assemblage was distinct based on its spectral signature. Based on the regional tectonic setting, the Kaishantun ophiolite suite probably experienced the blueschist facies metamorphic peak during subduction and greenschist facies retrograde metamorphism during later slab rollback.

The Huajian gold deposit is one of the largest hydrothermal intrusion-related gold deposits in eastern Hebei Province, located in the northern margin of the North China Craton (NCC). The mineralization in this district displays a close spatial association with the shoshonitic Niuxinshan intrusive complex (NIC), which contributes to the characterization of the metallogeny associated with convergent margin magmatism. In the current study, new geochronological and geochemical data are combined with previously published isotopic data, obtained from the granitic rocks in the NIC, to constrain the timing of the district's tectonic setting transformation and determine its bearing on regional metallogeny. The new geochronological data constrain the timing of the tectonic transformation between 155 and 185 Ma. The NIC's granitic rocks can be geochemically subdivided into two groups. One group's geochemical signature exhibits steep rare earth element (REE) patterns with negligible Eu anomalies, lower Yb, higher Sr, and negative Nb-Ta-Ti (NTT) anomalies, which indicate a volcanic-arc environment with a thickened crust in a convergent setting. The other group exhibits flat REE patterns with obvious negative Eu anomalies, higher Yb, lower Sr, and weak NTT anomalies, which indicate an intra-plate extensional environment with a thinning crust. Combining geochronologic and isotopic data, the mineralization is Late Jurassic (~155 Ma). This is interpreted to be genetically related to the crystallization of the shallow crustal-sourced portions of this complex. Additionally, a tectonic model is presented that provides a plausible explanation for the abundant polymetallic mineralization that occurs in the northern margin of the NCC after 155 Ma.

Spin-orbit coupling (SOC) is expected to partly determine the topologically nontrivial electronic structure of heavy half-Heusler ternary compounds. However, to date, attempts to experimentally observe either the strength of SOC or how it modifies the bulk band structure have been unsuccessful. By using bulk-sensitive nuclear magnetic resonance (NMR) spectroscopy combined with first-principles calculations, we reveal that 209Bi NMR isotropic shifts scale with relativity in terms of the strength of SOC and average atomic numbers, indicating strong relativistic effects on NMR parameters. According to first-principles calculations, we further claim that nuclear magnetic shieldings from relativistic p1/2 states and paramagnetic contributions from low-lying unoccupied p3/2 states are both sensitive to the details of band structures tuned by relativity, which explains why the hidden relativistic effects on band structure can be revealed by 209Bi NMR isotropic shifts in topologically nontrivial half-Heusler compounds. Used in complement to surface-sensitive methods, such as angle resolved photon electron spectroscopy and scanning tunneling spectroscopy, NMR can provide valuable information on bulk electronic states., accepted for publication in Scientific Reports (2016)