查找使用阿拉丁产品的科研文献

Recovery of rare earths from rare earth molten salt electrolytic slag using alkali phase reconstruction method with the aid of external electric field

Yusufujiang Mubula,Mingming Yu,Hongju Gu,Lei Wang,Man Chen,Tingsheng Qiu,Guangjun Mei

Rare earth molten salt electrolytic slag (RMES) has emerged as a promising secondary resource for rare earth elements (REEs). This study introduces an innovative leaching technique for extracting REEs from RMES under atmospheric conditions, employing an alkali phase reconstruction method followed by an acid leaching process. Additionally, the external electric field was employed to enhance the reaction. Under the optimal reaction conditions: NaOH initial concentration of 70 wt%, NaOH-slag mass ratio of 4:1, temperature of 160 °C, current density of 1000 A/m 2 , reaction time of 90 min, stirring speed of 300 r/min, HCl concentration of 4 mol/L, liquid-solid ratio of 15:1, and leaching time of 20 min, the leaching efficiencies of Nd and Pr reach up to 99.21% and 99.14%, respectively. Phase analysis indicates that the rare earth fluorides transform into rare earth hydroxides, significantly enhancing their solubility in acid solution. The imposition of an external electric field leads to pronounced disruption of the RMES surface, thereby promoting the formation of stable reactive oxygen species in the alkaline medium. This facilitates the decomposition of fluorinated rare earths and hastens the phase reconstruction, resulting in an enhanced leaching process. The achieved leaching efficiency with an external electric field is 37% higher than that without an electric field.

Acceleration of optimizing the dielectric properties of (Ca0.7Nd0.2)1−x(Li0.5Nd0.5)xTi1−y(Mg1/3Nb2/3)yO3 with the aid of machine learning

Ziqi Ni,Fenglin Wang,Yeqing Guan,Kaijia Hu,Fengyuan Zhao,Xingyu Chen,Yicong Ye,Weijun Zhang,Shuxin Bai

The three key properties required for microwave dielectric ceramics are suitable dielectric constant ( ε r ), high quality factor ( Q × f ), and near-zero temperature coefficient of resonant frequency ( τ f ). Due to the intricate coupling relationship among these three properties, regulating one often leads to the deterioration of the remaining two. In this study, the synergetic regulation of dielectric properties of Ca 0.7 Nd 0.2 TiO 3 was investigated to reduce τ f to near-zero while maintaining its high ε r by A- and B-site substitutions. To avoid the seesaw effect and improve the efficiency of composition optimization, machine learning method was introduced in this study. First, the models for predicting dielectric properties were fitted based on a small amount of high-quality data gathered via a uniform experimental design. Then the dielectric properties of 1037 compositions of (Ca 0.7 Nd 0.2 ) 1− x (Li 0.5 Nd 0.5 ) x Ti 1− y (Mg 1/3 Nb 2/3 ) y O 3 were predicted, from which 69 microwave dielectric ceramics with near-zero τ f and adjustable ε r of 95–125 were quickly picked out, and 5 of them were proved by experiments with very high prediction accuracy. This work was finished within a period of 1 month, which proves the obvious acceleration of composition designing process of microwave dielectric ceramics with the aid of machine learning.

Study on the Phase Equilibrium of Na+, K+//Cl–, CO32––H2O and Single-Salt of Potassium Separation with the Aid of Compressed CO2

Zhongshu Li,Yuli Xue,Xiaoling Tan,Wenqing Li,Shaonan Xu,Ziyan Wang,Jian Wang,Lina Li,Shiding Miao

It is of great importance to separate potassium salts from carbonate-based lakes, especially the low-[K+] but high-[Na+] brine which has been discovered around the world. Here the phase diagram of the quaternary system Na+, K+//Cl–, CO32––H2O was experimentally studied at 298.15 K via the method of isothermal evaporation, and the results corrected the previous diagram reported by Blasdale (J. Am. Chem. Soc.1923, 45, 2935–2946). The type of salts appeared and their solubility during the evaporation, and the density vs composition diagram and the pH values were plotted based on the experimental data. It was found that there were six invariant points, seven univariant curves, and five crystallization fields in the equilibrium phase diagram. To extract single-salt of potassium, certain areas in the Na+, K+//Cl–, CO32––H2O diagram were chosen to be acidified by the compressed CO2, and potassium in the form of KHCO3 was precipitated from the mother solution. The compressed CO2 was able to avoid formation of NaKCO3·6H2O during evaporation of the original system Na+, K+//Cl–, CO32––H2O. Based on experiment data, the region area for potassium salt extraction was determined, and this area was suitable for extracting K+ salts from brines with a [Na+/K+] ratio even lower than 0.44. This strategy opened a new way to recovery of potassium with a maximum yield of 59.88% from the carbonate-chloride-based brine.

Sensitive determination of Amaranth in drinks by highly dispersed CNT in graphene oxide “water” with the aid of small amounts of ionic liquid

Meiling Wang,Yinlu Sun,Xiongbo Yang,Jianwei Zhao

Graphene oxide (GO) is a pH-dependent amphiphile. In this paper, it was found that carbon nanotubes (CNTs) can be highly dispersed in graphene oxide “water” with the aid of prototype ionic liquid of 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF 6 ]). The introduction of [BMIM][PF 6 ] not only can minimize the defects of poor electrical conductivity of GO, but also can improve the dispersibility of CNT in water. Hence, a new composite of CNT/GO-[BMIM][PF 6 ] with high dispersibility and strong conductivity was presented for the first time and employed in the sensitive determination of Amaranth in soft drinks. The detection limit achieved (0.1   nM) is much lower than the guideline values in soft drinks. The ease of preparation, low background current, high sensitivity and stability can create novel avenues and applications for fabricating robust sensors for determination of other azo dyes in foods.

Tailor-made PEG-DA-CuS nanoparticles enriched in tumor with the aid of retro Diels–Alder reaction triggered by their intrinsic photothermal property

Jie Sheng,Beibei Ma,Qian Yang,Chao Zhang,Zhongying Jiang,Entomack Borrathybay

A simple extraction method for norfloxacin from pharmaceutical wastewater with a magnetic core–shell molecularly imprinted polymer with the aid of computer simulation

Muchuan Niu,Cheng Sun,Kai Zhang,Geyuan Li,Fizir Meriem,Chuong Pham-Huy,Xuanhong Hui,Jianrong Shi,Hua He

A simple and effective method was developed for norfloxacin detection using an innovative magnetic molecularly imprinted polymer (MMIP) with the aid of computer simulation. The best two functional monomers are selected according to the docking results. Four kinds of MMIP were synthesized with different functional monomers (methylacrylic acid and acrylamide) and solvents (dimethylsulfoxide and ethanol). The zeta potential was introduced to explain the interaction mechanism between MMIP and norfloxacin when the pH system was optimized. The final MMIP (MMIP-1) possesses a high efficiency recognition for norfloxacin (163.07 μg mg−1) because of the thin layer of MIP (30 nm). Transmission electron microscopy shows uniform morphology for MMIP-1 (460 nm) with a core–shell structure. Fourier transform infrared spectroscopy and vibrating sample magnetometry were used to study the chemical groups and magnetic properties of the materials. MMIP-1 possesses a high imprinting factor (greater than 3). A possible mechanism for the adsorption behavior was briefly explained with the Freundlich model and rate controlled steps. Simulated pharmaceutical wastewater was used for method validation and the method was then used to research using the method with real pharmaceutical wastewater. Because of its good properties, MMIP-1 proved to be an effective material when applied for norfloxacin extraction in complex pharmaceutical wastewater with detection using high performance chromatography.

Thermosetting polyurethanes prepared with the aid of a fully bio-based emulsifier with high bio-content, high solid content, and superior mechanical properties

Lingxiao Liu,Jingyi Lu,Yi Zhang,Haiyan Liang,Dunsheng Liang,Jizhou Jiang,Qiming Lu,Rafael L. Quirino,Chaoqun Zhang

In this paper, a novel, fully bio-based emulsifier has been successfully prepared from epoxidized soybean oil and glutaric acid through a solvent-free and self-catalysis method. The effects of reaction time and carboxyl : epoxy molar ratios on the structures of the emulsifier were systematically investigated. This novel emulsifier exhibits properties similar to those of dimethylolpropionic acid (DMPA) and dimethylolbutanoic acid (DMBA), with hydroxyl groups serving as crosslinking agents and the carboxylic acid group acting as an ionic segment. In order to validate the robustness of this emulsifier, a series of anionic, waterborne polyurethane dispersions were prepared from typical polyols (vegetable oil- and petroleum-based). The structure of this emulsifier and its good compatibility with bio-based polyols confer the resulting dispersions excellent storage stability and high solid content (up to 45%). The prepared waterborne polyurethane films exhibited higher toughness and thermal stability than traditional solvent-based polyurethane films and waterborne polyurethane films prepared from DMPA and DMBA. Moreover, a high bio-based content of up to 74% was achieved for the prepared polyurethanes. This new environmentally friendly, liquid emulsifier, prepared using a solvent-free and self-catalysis synthetic route, can potentially replace typical petroleum-based emulsifiers for the production of waterborne polyurethanes.

Expression and characterization of activation-induced deaminase (AID) with dehydroaminase activity and its localization in IgM+ lymphocytes of spleen of common carp (Cyprinus carpio)

Guangcai Wei,Jianhui Zhao,Qingyun Zuo,Manting Sun,Hua Wei,Haofeng Wang,Guiwen Yang,Eakapol Wangkahart,Lei Wang,Fumiao Zhang

Activation-induced deaminase (AID) is a key enzyme that catalyzes the deamination of cytosine to uracil in DNA, driving somatic hypermutation (SHM) and class switch recombination (CSR) of antibody genes to promote antibody diversification in the adaptive immunity. The AID gene from Cyprinus carpio (CcAID) has a full-length open reading frame of 633 bp and encodes a protein of 210 amino acids. CcAID shares structural and functional similarities with apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like (APOBEC) family members and contains a conserved catalytic domain characteristic of cytidine deaminases. Notably, the absence of two key phosphorylation sites in CcAID (Ser38 and Tyr184) may be a significant factor contributing to the markedly lower levels of somatic hypermutation (SHM) in teleost fish. A high level of CcAID transcript expression was detected in carp larvae on the sixth day after fertilization. Intraperitoneal injection of T-independent and T-dependent antigens preferentially upregulated CcAID expression in head kidney and splenic lymphocytes. Immunofluorescence analysis confirmed its expression in IgM + spleen lymphocytes. Recombinant CcAID exhibited cytidine deaminase activity. These findings indicate that CcAID is specifically expressed in IgM + spleen lymphocytes, suggesting its potential role in antibody production.

Differentiation between wild and artificial cultivated Stephaniae tetrandrae radix using chromatographic and flow-injection mass spectrometric fingerprints with the aid of principal component analysis

Ya-dong Qin,Feng-man Fang,Rong-bin Wang,Juan-juan Zhou,Lin-hua Li

High-performance liquid chromatographic (HPLC) and flow-injection mass spectrometric (FIMS) fingerprinting profiles were used to differentiate between wild and artificial cultivated Stephaniae tetrandrae Radix samples. HPLC and FIMS fingerprints of 15 wild S. tetrandrae Radix samples and 12 artificial cultivated S. tetrandrae Radix samples were obtained and analyzed with the aid of principal component analysis (PCA). PCA of the fingerprints showed that the chemical differences between wild and artificial cultivated S. tetrandrae Radix samples could be differentiated by either HPLC or FIMS fingerprints. The HPLC fingerprints provided more chemical information but required longer analytical time compared with FIMS fingerprints. This study indicated that the wild samples contained higher concentrations of almost all of the major compounds than the cultivated samples. Three characteristic compounds which were responsible for the differences between the samples were tentatively identified with the aid of MS data. Furthermore, these three compounds, tetrandrine (TET), fangchinoline (FAN), and cyclanoline (CYC), were quantified. The HPLC and FIMS fingerprints combined with PCA could be used for quality assessment of wild and artificial cultivated S. tetrandrae Radix samples.

Effects of adding 5–20 mol% ZrC plus 5 mol% Cu as a sintering aid on microstructure and mechanical properties of the TaC ceramics

Limeng Liu,Guihong Geng,Wanxiu Hai,Yuhong Chen,Laner Wu

TaC ceramics were prepared by hot pressing at 1900   °C for 30   min under 30   MPa mechanical pressure. Effects of the addition of 20   mol% ZrC or 5–20   mol% ZrC plus 5   mol% Cu as sintering aids on densification , phase composition, microstructure and mechanical properties of the consolidated materials were investigated. The results showed the pure TaC had a relative density of 86%of the theoretical value. Densities >97% theoretical were reached in the materials when the sintering aids were used. ZrC and TaC reacted to form solid solutions . The grain average size decreased from 18   µm in the pure TaC to 6   µm at 20   mol% addition. Addition of 5   mol% Cu further refined the microstructures. The 20   mol% ZrC+5   mol% Cu and the 10   mol% ZrC+5   mol% Cu composition had good flexural strength of 608   MPa and fracture toughness of 5.4   MPa   m 1/2 , respectively.

Quality Assessment of Different Species and Differently Prepared Slices of Zedoray Rhizome by High-Performance Liquid Chromatography and Colorimeter with the Aid of Chemometrics

Fei Sun,Xiaolu Yang,Fei Liu,Ying Zhang,Shumei Wang,Hui Cao,Jiang Meng

In this study, high-performance liquid chromatography (HPLC) and colorimeter were applied to evaluate the quality of different species and differently prepared slices of Zedoray Rhizome samples with the aid of chemometric tools. Fifty batches of Zedoray Rhizome samples from different species and forty-two batches of Zedoray Rhizome samples from differently prepared slices were collected. The quantitative method was developed using HPLC to simultaneously determine the contents of twelve chemical ingredients in Zedoray Rhizome. The colour parameters L, a, and b were measured by a colorimeter. Then, the collected data were analyzed by the principal component analysis and Pearson correlation analysis. The results showed that the proposed method was capable of accurately determining the contents of the twelve chemical ingredients and the colour parameters for the collected samples. There was a dramatic difference in the contents of the chemical ingredients and in the colour parameters among different species and differently prepared slices of Zedoray Rhizome samples. This study reveals that combining HPLC, colorimeter, and chemometric tools can provide a new approach to comprehensively evaluate the quality of Zedoray Rhizome samples.

Reducing the grain gap and improving the saturation magnetization of co-fired YIG-Al0.1/NZF-Zn0.4 ferrite composite substrates with an ASBP-glass sintering aid

Pingan Tan,Xiaoyan Zhong,Jingsong Liu,Fei Yang,Chong Xian,Honglan Yuan

Ni 0.6 Zn 0.4 Fe 2 O 4 (NZF-Zn 0.4 ) ferrites with different Al–Si–B–Pb (ASBP) glass additions were synthesized via a solid-phase reaction method at 1175 °C. The inclusion of ASBP-glass significantly enhances the grain size, density, shrinkage, and magnetic properties of NZF-Zn 0.4 ferrites without introducing impurity phases. The prepared NZF-Zn 0.4 -1 wt%ASBP ferrites not only exhibit appropriate radial shrinkage but also possess a dense microstructure and outstanding magnetic properties. Subsequently, Y 2.4 Bi 0.5 Al 0.1 Fe 3 O 4 (YIG-Al 0.1 ) ferrites and NZF-Zn 0.4 -1 wt%ASBP ferrites were chosen as the outer rings and inner cores, respectively. Tightly interconnected YIG-Al 0.1 /NZF-Zn 0.4 –1wt.% ASBP ferrite composite substrates were successfully co-fired within the temperature range of 1175 °C–1225 °C following co-pressing. Furthermore, YIG-Al 0.1 /NZF-Zn 0.4 -1 wt%ASBP composite substrates, co-fired at 1175 °C, exhibit a lack of impurity phases in the interface region, minimal element diffusion, and exceptional electromagnetic properties (NZF-Zn 0.4 -1 wt%ASBP: M s  = 81.88 ± 0.05 emu/g; YIG-Al 0.1 : ε r  = 18.28 ± 0.05@11.17 GHz, tanδ = 3.14 ± 0.55 × 10 −4 , M s  = 21.62 ± 0.55 emu/g). The wide co-firing temperature range of YIG-Al 0.1 /NZF-Zn 0.4 -1 wt%ASBP composite substrates significantly enhances the shrinkage matching rate of two-phase ferrites, and its exceptional electromagnetic properties hold significant potential for applications in RF band circulators.