A novel mixed hemimicelles solid phase extraction based on magnetic graphene oxide (Fe3O4/GO) and ionic liquid (IL) was developed for the simultaneous extraction and determination of trace ...cephalosporins in spiked human urine. The high surface area and excellent adsorption capacity of the graphene oxide after modification with1-hexadecyl-3-methylmidazoliumbromide(C16mimBr) were utilized adequately in the solid phase extraction(SPE) process. A comprehensive study of the parameters affecting the extraction recovery, such as the zeta-potential of magnetic graphene oxide, amounts of magnetic graphene oxide and surfactant, pH of solution, ionic strength, extraction time, and desorption condition were optimized. A comparative study on the use of different surfacant-coated Fe3O4/GO NPs as sorbents was presented. Good linearity (R2>0.9987) for all calibration curves was obtained. The LODs were ranged between 0.6 and 1.9ng mL−1 for the cephalosporins and the LOQs were 1.5 to 5.5, respectively. Satisfactory recoveries(84.3% to 101.7%)and low relative standard deviations from 1.7% to 6.3% in biological matrices were achieved. The mixed hemimicelles magnetic SPE (MSPE) method based on ILs and Fe3O4/GO NPs magnetic separation has ever been successfully used for pretreatment of complex biological samples.
•The granitoids episodically emplaced at ∼2.50 and 2.45Ga.•The granitoids underwent multi-stage metamorphism at ∼2.50, 2.45 and 1.90–1.95Ga.•The granitoids have a source of juvenile crust.•The ...granitoids represent subduction-related juvenile magmatic arcs.•The KB underwent long-term arc-continent accretion during late Neoarchean-Paleoproterozoic.
Late Neoarchean-early Paleoproterozoic granitoid rocks are widely exposed in the Daqingshan–Wulashan area in the central segment of the Khondalite Belt (KB), Western Block, North China Craton (NCC), and are characterized by widespread evidence of ductile deformation and anatexis. To improve our understanding of the formation and evolution of the KB, in this study we analyzed zircon U–Pb ages, zircon Lu–Hf isotopes, and whole-rock geochemistry of the granitoid rocks. LA–ICP–MS U–Pb analysis of zircons from eight representative granitoid samples indicates the granitoid rocks were emplaced at ca 2.45 and ca 2.50Ga, and underwent multi-stage metamorphism at ca 1.90–1.95, 2.45, and 2.50Ga. Zircon Lu–Hf isotopic analysis shows that the granitoids have positive zircon εHf(t) values with an average of +4.36, and two-stage depleted mantle zircon Hf model ages (TDM2) clustering around 2.7–3.0Ga, indicative of a juvenile crustal source that formed at ca 2.7–3.0Ga. Furthermore, whole-rock geochemical analysis of 34 granitoid samples reveal them to be magnesian, low- to high-K, calcic to calc-alkalic, and metaluminous to weakly peraluminous (alumina saturation index (ASI)=0.74–1.17). They are characterized by high total rare-earth-element (REE) contents (57.45–346.96ppm), enrichment in light REE, and depletion in heavy REE with (La/Yb)n ratios of 8.33–224.16. They have weak Eu anomalies (Eu/Eu∗=0.37–2.53, average=1.08), high Sr contents (>300ppm), and relatively low Y and Yb concentrations (average=10.55 and 0.96ppm, respectively). Primitive-mantle-normalized trace-element diagrams show that the granitoid samples are depleted in high-field-strength elements (Nb, Ta, U and Ti) and enriched in large-ion lithophile elements (Ba, K, Rb and Sr). In general, the samples have geochemical characteristics consistent with cordilleran I-type granitoids, which form in subduction-related magmatic arcs. Therefore, our results, together with the occurrence of synchronous mafic rocks and other available geological data, indicate the KB contains multiple magmatic arcs and underwent long-term deposition and multi-phase metamorphism, analogous to Phanerozoic accretionary orogens such as the Cordilleran orogen. Consequently, we infer that the KB underwent long-term arc-continent accretion along the southern margin of the Yinshan Block during the late Neoarchean–Paleoproterozoic, and late-stage continent–continent collision between the Yinshan and Ordos blocks at ca 1.90–1.95Ga.
Objectives
To study the added value of mean and entropy of apparent diffusion coefficient (ADC) values at standard (800 s/mm
2
) and high (1500 s/mm
2
)
b
-values obtained with diffusion-weighted ...imaging in identifying histologic phenotypes of invasive ductal breast cancer (IDC) with MR imaging.
Methods
One hundred thirty-four IDC patients underwent diffusion-weighted imaging with
b
-values of 800 and 1500 s/mm
2
, and corresponding ADC
800
and ADC
1500
maps were generated. Mean and entropy of volumetric ADC values were compared with molecular markers (estrogen receptor ER, progesterone receptor PR, human epidermal growth factor receptor 2 HER2, and Ki-67). Associations among morphologic features, ADC metrics, and phenotypes (luminal A, luminal B HER2 negative, luminal B HER2 positive, HER2 positive, and triple negative) were evaluated.
Results
Mean ADC values were significantly decreased in ER-positive, PR-positive, and HER2-negative tumors (
p
< 0.01). Ki-67 ≥ 20% tumors demonstrated significantly higher ADC entropy values compared with Ki-67 < 20% tumors (
p
< 0.001). Luminal A subtype tended to display lower ADC entropy values compared with other subtypes, while HER2-positive subtype tended to display higher mean ADC values. ADC
1500
entropy provided superior diagnostic performance over ADC
800
entropy (
p
= 0.04). Independent risk factors were ADC
1500
entropy (
p
= 0.002) associated with luminal A, irregular mass shape (
p
= 0.018) and ADC
1500
entropy (
p
= 0.022) with luminal B (HER2 positive), mean ADC
1500
(
p
= 0.018) with HER2 positive, and smooth mass margin (
p
= 0.012) and rim enhancement (
p
= 0.003) with triple negative.
Conclusions
Mean and entropy of ADC values provided complementary information and added value for evaluating IDC histologic phenotypes. High-
b
-value ADC
1500
may facilitate better phenotype discrimination.
Key Points
• ADC metrics are associated with molecular marker status in IDC.
• ADC
1500
improves differentiation of histologic phenotypes compared with ADC
800
.
• ADC metrics add value to morphologic features in IDC phenotyping.
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•Different metamorphic stages and anatexis recorded in the Wulashan metapelitic rocks.•The clockwise P–T paths and melt behavior are investigated using phase equilibria modeling.•The ...Wulashan metapelitic rocks were involved in collision of the Yinshan Block and the Ordos Block.
The Wulashan Complex in the Khondalite Belt, the North China Craton contains high-grade garnet-cordierite-sillimanite metapelitic rocks with anatectic record. The rocks preserve representative metamorphic assemblages of peak, post-peak near-isothermal decompression, and decompressional cooling stages. Combined with petrographic observation and P–T pseudosections of residual bulk compositions, a clockwise P–T path was inferred involving near-isothermal decompression and decompressional cooling that followed the peak metamorphism. Furthermore, based on phase equilibria modeling for the melt-reintegrated composition, a whole, clockwise P–T path with a possible pre-peak segment was inferred. In the pre-peak field of garnet+biotite+K-feldspar+plagioclase+sillimanite+quartz+magnetite+liquid, garnet was first introduced by consuming biotite, quartz, and plagioclase via the biotite dehydration melting reaction of Bt+Sil+Qz±Pl→Grt+Kfs+Melt. The peak metamorphic assemblage was interpreted to be garnet+biotite+K-feldspar+plagioclase+sillimanite+quartz+ilmenite+magnetite+liquid at 830–860°C and 9.5–11kbar. The following post-peak near-isothermal decompressional assemblage is garnet+biotite+cordierite+K-feldspar+plagioclase+quartz+magnetite+ilmenite+liquid at 840–880°C and 6.0–7.5kbar, resulting in matrix cordierite isolated from garnet due to the biotite decompressional dehydration melting reaction of Bt+Sil+Qz±Pl→Crd+Kfs±Ilm+Melt. Furthermore, subsequent decompressional cooling processes resulted in symplectites of cordierite and biotite+plagioclase mantling garnet due to the breakdown reactions: Grt+Sil+Melt→Crd+Bt+Fe-oxide, and Grt+Melt→Bt+Qz±Pl. Melt that remained in the host rocks formed thin films of plagioclase or K-feldspar distributed along plagioclase, quartz, and sillimanite grain boundaries. The results indicate that the Khondalite Belt experienced continent–continent subduction and collision followed by exhumation and cooling between the Yinshan and Ordos Blocks in the Western Block of the North China Craton, and the rocks of the Wulashan Complex were subjected to granulite-facies metamorphism accompanied by partial melting events.
Quality prediction is committed to predicting the key quality-related variables to obtain real-time feedback information for process control. To achieve the robust and transferable quality prediction ...of products processed in complex and uncertain manufacturing processes, deep learning methods have been developed. However, the training process of deep learning methods requires a large amount of annotated data to avoid overfitting, and the labeling process of quality-related variables is often time-consuming and labor-intensive. Therefore, few-shot quality prediction in a multistage manufacturing process is formalized to address the lack of annotated data and deal with previously unseen tasks without an additional training process. In addition, a novel contrastive decoder generator (CDG) is proposed to enable few-shot quality prediction, which consists of a machine feature encoder, a contrastive stage, and task feature generator, and an instance-specific decoder generator. Experiments are conducted on a public quality prediction dataset collected from an actual production line. The CDG achieves state-of-the-art results on this dataset for few-shot quality prediction settings, which proves the effectiveness of the CDG. Additionally, detailed experiments are performed to evaluate the roles of different modules in the CDG.
The Yellow River floodplain represents a fertile landmass that contributes significantly to human welfare and thus has been colloquially known as the birthplace of Chinese civilization. The ...sediment-laden nature of the Yellow River gave rise to a super-elevated channel belt, which is prone to failure particularly in the summer months when excessive precipitation occurs, resulting in cataclysmic floods traditionally regarded as “China’s Sorrow.” Therefore, a deeper understanding of levee breach frequency in this area is especially important for the assessment of socio-economic risk of levee breaches associated with future climate changes. To better understand the nature, evolution, and driving mechanisms of levee breaches on the lower Yellow River, it is necessary to place the instrumental data within a longer time framework. Here, we retrieve past information about levee breaches on the lower Yellow River since AD 11 from various documentary sources such as official histories of China. We evaluated each line of descriptions and narratives about the location, timing, and nature of each event in these documents, ending up with a detailed timeline of levee breaches on the lower Yellow River during the last 2000 years on an annual time scale. Our results reveal remarkable variations in the frequency of levee breaches superimposed on a long-term increasing trend. In addition to climate changes, the iterative embankment-siltation-breaching process caused a feedback: more breaches result in much more channel siltation, which in turn leads to even more breaches. The enhanced farming in the Loess Plateau played a pivotal role in the formation and operation of this positive feedback. Our findings may not only help improve the assessment of socio-economic risk of levee breaches associated with future climate changes, but also provide consulting information for hydraulic engineering and infrastructural designs in the lower Yellow river area.
Fiber probes for optical coherence tomography (OCT) recently employ a short section of step-index multimode fiber (SIMMF) to generate output beams with extended depth of focus (DOF). As the focusing ...region of the output beam is generally close to the probe end, it is not feasible to adopt the methods for bulk-optics with spatial pupil filters to the fiber probes with fiber-based filters. On the other hand, the applicable method of the beam propagation method (BPM) to the fiber probes is computationally inefficient to perform parameter scan and exhaustive search optimization. In this paper, we propose the method which analyzes the non-Gaussian beams from the fiber probes with fiber-based filters using the eigenmode expansion (EME) method. Furthermore, we confirm the power of this method in designing fiber-based filters with increased DOF gain and uniformly focusing by introducing more and higher-order fiber modes. These results using the EME method are in good agreement with that by the BPM, while the latter takes 1-2 orders more computation time. With higher-order fiber modes involved, a novel probe design with increased DOF gain and suppressed sidelobe is proposed. Our findings reveal that the fiber probes based on SIMMFs are able to achieve about four times DOF gain at maximum with uniformly focusing under acceptable modal dispersion. The EME method enables fast and accurate simulation of fiber probes based on SIMMFs, which is important in the design of high-performance fiber-based micro-imaging systems for biomedical applications.
The complex interaction between precipitation and dislocations challenges the determination of the effective precipitate nucleation temperature (Tnd) of dislocation-bearing supersaturated solid ...solutions, in particular, for the 2:17-type Sm-Co-based permanent magnets that evolve gradual formation and dissociation of dislocations during cellular precipitation. In this study, the early-stage decomposition behavior of a solution-treated Sm25Co50.2Fe16.2Cu5.6Zr3.0 (wt.%) alloy with highly-faulted 2:17H (hexagonal Sm2Co17) was investigated using in-situ high-energy synchrotron X-ray diffraction (HES-XRD) and ex-situ high-resolution transmission electron microscopy (HR-TEM). The nucleation and growth of 1:5H (hexagonal SmCo5) precipitate during heating and isothermal tempering were observed in situ, clarifying a dispute in 2:17-type Sm-Co-based magnets. The effective nucleation temperature Tnd of 1:5H precipitates was determined to be ∼760 °C, which is much higher than the starting transformation temperature of 2:17H to 2:17R (rhombohedral Sm2Co17) phase governed by diffusion-controlled glides of Shockley partials, Ta∼240 °C. TEM studies revealed that a pre-aging treatment at 550 °C (far below Tnd, but above Ta) causes dissociation of partial dislocations whereas a pre-aging treatment at 750 °C (slightly below Tnd) promotes the nucleation of 1:5H precipitates. As a result, after whole-process heat-treating, the final magnet with pre-aging at 750 °C possesses better magnetic properties than the one with pre-aging at 550 °C and the one without pre-aging. These results reveal that upon heating thermally-activated motion of dislocations occurs prior to sufficient atomic clustering into precipitate nuclei in 2:17-type Sm-Co-based magnets, providing direct guidance for designing proper material processing towards high-performance.
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Electrolytic manganese residue (EMR), a solid waste generated during electrolytic manganese production, exhibits substantial leaching toxicity owing to its elevated levels of soluble Mn2+ and NH4+. ...The leaching and recovery of valuable metal ions and NH4+ from EMR are key to the hazard-free treatment and resource utilization of EMR. In this study, two-stage countercurrent leaching with water was used to leach Mn2+, Mg2+, and NH4+ from EMR. Subsequently, two-stage countercurrent extraction was conducted using α-hydroxy-2-ethylhexyl phosphinic acid (α-H-2-EHA) as an extractant to enrich Mn2+, and Mg2+, and NH4+ were recovered via coprecipitation. Based on the calculations for a single leaching-extraction process, the recoveries of Mn2+, Mg2+, and NH4+ ions exceeded 80%, 99%, and 90%, respectively. In addition, high-purity Mn3O4 with an Mn content of 71.61% and struvite were produced. This process represents a win-win strategy that facilitates the hazard-free treatment of EMR while simultaneously recovering valuable Mn2+, Mg2+, and NH4+ resources from waste. Thus, this study provides a novel approach to the hazard-free and resourceful management of solid waste.
Electrolytic manganese residue (EMR), a solid waste generated during electrolytic manganese production, poses significant environmental risks due to its soluble heavy metals and ammonia nitrogen content. Efforts have been made to address this issue, but there has been no mature industrial application due to cost or processing capacity constraints. In this work, solvent extraction was first used to enrich Mn2+ from EMR leachate, and a novel α‑hydroxy‑2‑ethylhexyl phosphinic acid was used as extractant. High purity Mn3O4 and struvite was synthesized through this process. The win‑win strategy offers a novel approach for the hazard‑free and resourceful utilization of solid waste.
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•Solvent extraction was first introduced into the resource utilization of EMR.•Mn, Mg and NH4+ were sequentially recovered through solvent extraction.•Mn2+ were purified and enriched through extraction, and Mn3O4 was prepared.•The recovery ratio of Mg2+ and NH4+ exceed 90%, and struvite was prepared.
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