Publications by authors named "Mei Lei"

195 Publications

Stepwise Assembly of a Multicomponent Heterometallic Metal-Organic Framework via Th-Based Metalloligands.

Inorg Chem 2021 Sep 21. Epub 2021 Sep 21.

Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.

Herein we present a new metalloligand, ThL [IHEP-10; L = 4-pyrazolecarboxylic acid (HPyC)], which can be used to generate a novel multicomponent heterometallic metal-organic framework (MOF), [[Cu(μ-OH)(NO)(HO)]Th(μ-O)(μ-OH)(PyC)(HPyC)(HO)](NO) (IHEP-11), through further assembly with second [Cu(μ-OH)(PyC)] clusters. In IHEP-11, six Cu clusters are connected by six NO anions to form an unprecedented annular Cu cluster, which can be viewed as a 12-connected node to link with 12 Th clusters, resulting a 4,12-connected shp net. Benefiting from the cationic framework and 3D porous structure, IHEP-11 can efficiently remove ReO (an analogue of radioactive TcO) from aqueous solution in a wide pH range. This work highlights the feasibility of constructing multicomponent MOFs through a step-by-step synthesis strategy based on metalloligands.
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http://dx.doi.org/10.1021/acs.inorgchem.1c02082DOI Listing
September 2021

Mercury-Induced Phytotoxicity and Responses in Upland Cotton ( L.) Seedlings.

Plants (Basel) 2021 Jul 21;10(8). Epub 2021 Jul 21.

Institution of Crop Science, Zhejiang University, Hangzhou 310058, China.

Cotton is a potential and excellent candidate to balance both agricultural production and remediation of mercury-contained soil, as its main production fiber hardly involves into food chains. However, in cotton, there is known rarely about the tolerance and response to mercury () environments. In this study, the biochemical and physiological damages, in response to concentrations (0, 1, 10, 50 and 100 µM), were investigated in upland cotton seedlings. The results on germination of cottonseeds indicated the germination rates were suppressed by high levels, as the decrease of percentage was more than 10% at 1000 µM . Shoots and roots' growth were significantly inhibited over 10 µM . The inhibitor rates () in fresh weight were close in values between shoots and roots, whereas those in dry weight the root growth were more obviously influenced by . In comparison of organs, the growth inhibition ranked as root > leaf > stem. The declining of translocation factor () opposed the level as even low to 0.05 at 50 µM . The assimilation in terms of photosynthesis, of cotton plants, was affected negatively by , as evidenced from the performances on pigments ( and ) and gas exchange (Intercellular concentration (), assimilation rate () and stomatal conductance ()). Sick phenotypes on leaf surface included small white zone, shrinking and necrosis. Membrane lipid peroxidation and leakage were dose-dependent as indicated by malondialdehyde () content and relative conductivity () values in leaves and roots. More than 10 µM damaged antioxidant enzyme system in both leaves and roots ( < 0.05). Concludingly, 10 µM post negative consequences to upland cotton plants in growth, physiology and biochemistry, whereas high phytotoxicity and damage appeared at more than 50 µM concentration.
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http://dx.doi.org/10.3390/plants10081494DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8398479PMC
July 2021

Understanding of remora's "hitchhiking" behaviour from a hydrodynamic point of view.

Sci Rep 2021 Jul 21;11(1):14837. Epub 2021 Jul 21.

Department of Naval Architecture, Ocean & Marine Engineering, University of Strathclyde, Henry Dyer Building, 100 Montrose Street, Glasgow, G4 0LZ, UK.

Symbiotic relationships have developed through natural evolution. For example, that of the remora fish attached to the body of a shark. From the remora's perspective, this could be associated to an increased hydrodynamic efficiency in swimming and this needs to be investigated. To understand the remora's swimming strategy in the attachment state, a systematic study has been conducted using the commercial Computational Fluid Dynamics (CFD) software, STAR-CCM + to analyse and compare the resistance characteristics of the remora in attached swimming conditions. Two fundamental questions are addressed: what is the effect of the developed boundary layer flow and the effect of the adverse pressure gradient on the remora's hydrodynamic characteristics? According to the results, the resistance of the remora can generally be halved when attached. Besides, the results have also demonstrated that the drag reduction rate increases with the developed boundary layer thickness and can be estimated using the boundary layer thickness ratio and velocity deficit. The paper demonstrates that the most frequent attachment locations are also the areas that provide the maximum drag reduction rate.
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http://dx.doi.org/10.1038/s41598-021-94342-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8295263PMC
July 2021

A Rat Model of Orthopedic Implant-Associated Infection for Identification of Staphylococcal Biofilm Proteins.

Methods Mol Biol 2021 ;2341:117-125

Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR, USA.

Secreted bacterial proteins are difficult to identify directly from an infection site due to a limited amount of bacteria and presence of a large quantity of host proteins. Here we describe a rat model of orthopedic implant that allows us to harvest bacterial biofilm materials sufficient for identification of bacterial proteins in the biofilm matrix by liquid chromatography-tandem MS (GeLC-MS/MS) analysis.
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http://dx.doi.org/10.1007/978-1-0716-1550-8_14DOI Listing
August 2021

Double-Layer Nitrogen-Rich Two-Dimensional Anionic Uranyl-Organic Framework for Cation Dye Capture and Catalytic Fixation of Carbon Dioxide.

Inorg Chem 2021 Aug 15;60(15):11485-11495. Epub 2021 Jul 15.

Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.

A novel two-dimensional double-layer anionic uranyl-organic framework, U-TBPCA {[NH(CH)][(UO)(TBPCA)], where HTBPCA = 4,4',4″--triazine-1,3,5-triyltripamino-methylene-cyclohexane-carboxylate}, with abundant active sites and stability was obtained by assembling UO(NO)·6HO and a triazine tricarboxylate linker, TBPCA. Due to the flexibility of the ligand and diverse coordination modes between carboxyl groups and uranyl ions, U-TBPCA exhibits an intriguing topological structure and steric configuration. This double-layer anionic uranyl-organic framework is highly porous and can be used for selective adsorption of cationic dyes. Due to the presence of high-density metal ions and basic -NH- groups, U-TBPCA acts as an effective heterogeneous catalyst for the cycloaddition reaction of carbon dioxide with epoxy compounds. Moreover, the various modes of coordination between the tricarboxylic ligand and uranyl ion were studied by density functional theory calculations, and several simplified models were established to probe the influence of hydrogen bonding between carbon dioxide and U-TBPCA on the ability of U-TBPCA to bind carbon dioxide. This work should aid in improving our understanding of the coordination behavior of uranyl ion as well as the development and utilization of new actinide materials.
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http://dx.doi.org/10.1021/acs.inorgchem.1c01492DOI Listing
August 2021

Source-specific ecological and health risks of potentially toxic elements in agricultural soils in Southern Yunnan Province and associated uncertainty analysis.

J Hazard Mater 2021 09 18;417:126144. Epub 2021 May 18.

Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing, China, 100101; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address:

Source-specific risk apportionment is critical to prevent and control soil potentially toxic element (PTE) pollution. This study explored source-specific ecological and human health risks of soil PTEs in Southern Yunnan Province. Geochemical baseline values were determined to assess the pollution level of PTEs; then source-specific risk was apportioned combining positive matrix factorization (PMF) with ecological and human health risk assessment. Obvious accumulation of As, Cd, Pb, and Zn was observed in this area, especially Cd in 21.33% of the samples exhibited significant enrichment. Four sources were quantified based on PMF assisted with GIS-mapping: natural sources (41.49%), traffic emissions (24.70%), industrial activities (17.48%), and agricultural activities (16.33%). Industrial activities were the largest source (64.55%) to ecological risk. Agricultural activities were regarded as the major contributor to non-carcinogenic (adults: 75.93%, children: 62.33%) and carcinogenic risks (adults: 55.97%, children: 56.36%). Non-carcinogenic and carcinogenic risks for children were higher than adults, and their health risks showed similar trend. Thus, agricultural activities should be regarded as a priority to reduce health risk, whereas industrial activities should be given priority to control ecological risk. Although source-specific risk was quantified, combination with bioavailability and interactions of PTEs are necessary to obtain more accurate results in future.
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http://dx.doi.org/10.1016/j.jhazmat.2021.126144DOI Listing
September 2021

Proximity Effect in Uranyl Coordination of the Cucurbit[6]uril-Bipyridinium Pseudorotaxane Ligand for Promoting Host-Guest Synergistic Chelating.

Inorg Chem 2021 Jul 2;60(14):10522-10534. Epub 2021 Jul 2.

Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, P. R. China.

In the present work, we proposed regulating uranyl coordination behavior of cucurbituril-bipyridinium pseudorotaxane ligand by utilizing meta-functionalized bipyridinium dicarboxylate guest. A tailored pseudorotaxane precursor involving 1,1'-(hexane-1,6-diyl)bis(3-cyanopyridin-1-ium) bromide () and cucurbit[6]uril (CB[6]) has designed and synthesized. Through in situ hydrolysis of the pseudorotaxane ligands and their coordination assembly with uranyl cations, seven new uranyl-rotaxane coordination polymers have been obtained under hydrothermal conditions in the presence of different anions. It is demonstrated that the variation of carboxylate groups from para- to meta-position greatly affected the coordination behaviors of the meta-functionalized pseudorotaxane linkers, which are enriched from simple guest-only binding to host-guest simultaneous coordination and synergistic chelating. This effective regulation on uranyl coordination of supramolecular pseudorotaxane can be attributed to the proximity effect, which refers to the meta-position carboxyl group being spatially closer to the portal carbonyl group of CB[6]. Moreover, by combining other regulation methods such as introducing competing counterions and modulating solution acidity, the nuclearity of the uranyl center and the coordination patterns of the pseudorotaxane ligand can be diversely tuned, which subsequently exert great influence on the final dimensionality of resultant uranyl compounds. This work presents a large diversity of uranyl-based coordination polyrotaxane compounds with fascinating mechanically interlocked components and, most importantly, provides a feasible approach to adjust and control the metal coordination behavior of the pseudorotaxane ligand that might expand the scope of application of such supramolecular ligands.
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http://dx.doi.org/10.1021/acs.inorgchem.1c01177DOI Listing
July 2021

Molecular tension in syndecan-1 is regulated by extracellular mechanical cues and fluidic shear stress.

Biomaterials 2021 08 12;275:120947. Epub 2021 Jun 12.

Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, USA; Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX, USA; Institute for Biomaterials, Drug Delivery and Regenerative Medicine, University of Texas at Austin, Austin, TX, USA; The Institute for Computational Engineering and Sciences, University of Texas at Austin, Austin, TX, USA. Electronic address:

The endothelium plays a central role in regulating vascular homeostasis and is key in determining the response to materials implanted in the vascular system. Endothelial cells are uniquely sensitive to biophysical cues from applied forces and their local cellular microenvironment. The glycocalyx is a layer of proteoglycans, glycoproteins and glycosaminoglycans that lines the luminal surface of the vascular endothelium, interacting directly with the components of the blood and the forces of blood flow. In this work, we examined the changes in mechanical tension of syndecan-1, a cell surface proteoglycan that is an integral part of the glycocalyx, in response to substrate stiffness and fluidic shear stress. Our studies demonstrate that syndecan-1 has higher mechanical tension in regions of cell adhesion, on and in response to nanotopographical cues. In addition, we found that substrate stiffness also regulated the mechanical tension of syndecan-1 and altered its binding to actin, myosin iiB and signaling intermediates including Src, PKA and FAK. Application of fluidic shear stress created a gradient in tension in syndecan-1 and led to enhanced association with actin, Src, myosin IIb and other cytoskeleton related molecules. Overall, our studies support that syndecan-1 is responsive to the mechanical environment of the cells and alters its association with actin and signaling intermediates in response to mechanical stimuli.
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http://dx.doi.org/10.1016/j.biomaterials.2021.120947DOI Listing
August 2021

An effective method for determining the optimal sampling scale based on the purposes of soil pollution investigations and the factors influencing the pollutants.

J Hazard Mater 2021 09 3;418:126296. Epub 2021 Jun 3.

Beijing Key Laboratory of Remediation of Industrial Pollution Sites, Environmental Protection Research Institute of Light Industry, Beijing Academy of Science and Technology, Beijing 100089, China.

There is a lack of a systematic method for determining the optimal sampling scale based on the purposes of soil pollution investigations (purpose) and the factors influencing of pollutants, which could affect the accuracy of determining pollution scope of the pollution. Therefore, in this study, both the purpose and the influencing factors were considered to determine the optimal sampling scale. The conclusions were obtained through geostatistical and spatial analysis. (1) The optimal sampling scale should account for 3% of the range of the pollutants, which can identify pollution information and minimize sampling costs. (2) The optimal sampling scale should be set to 3% of the range of the main factor influencing the pollutants in the absence of prior pollution information. (3) The greater the influences of the factors on the pollutants, the closer the optimal sampling scale calculated according to the influencing factors will be to that calculated based on the purpose. (4) The method of determination based on both the purpose and the influencing factors was concluded to be rational and reliable based on validation and advantage analysis. These results provide a method for soil pollution investigation that can minimize costs and improve the representativeness of the sample sites.
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http://dx.doi.org/10.1016/j.jhazmat.2021.126296DOI Listing
September 2021

An Azobenzene-Modified Photoresponsive Thorium-Organic Framework: Monitoring and Quantitative Analysis of Reversible Photoisomerization.

Inorg Chem 2021 Jun 7;60(12):8519-8529. Epub 2021 Jun 7.

Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, People's Republic of China.

Monitoring and quantification of the photoresponsive behavior of metal-organic frameworks that respond to a light stimulus are crucial to establish a clear structure-activity relationship related to light regulation. Herein, we report the first azobenzene-modified photoresponsive thorium-organic framework ( with the formula [ThO(OH)(HO)] (H = ()-2'--tolyldiazenyl-1,1':4',4'-terphenyl-4,4″-dicarboxylic acid), in which the utilization of a thorium cluster as a metal node leads to one of the largest pore sizes among all the azobenzene-containing metal-organic frameworks (MOFs). The phototriggered transformation of the isomer to the isomer is monitored and characterized quantitatively by comprehensive analyses of NMR and UV spectroscopy, which reveals that the maximum isomerization ratio of in the solid state is 19.7% after irradiation for 120 min, and this isomerization is reversible and can be repeated several times without apparent performance changes. Moreover, the isomerization-related difference in the adsorption of the Rhodamine B guest is also illustrated and a possible photoregulated mechanism is proposed. This work will shed light on new explorations for constructing functionalized actinide porous materials by the elegant combination of actinide nodes with tailored organic ligands and furthermore will provide a comprehensive understanding of photoisomerization processes in MOF solids and insight into the mechanism on photoregulated cargo adsorption and release by photoactive MOFs.
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http://dx.doi.org/10.1021/acs.inorgchem.1c00217DOI Listing
June 2021

CT-guided radiofrequency treatment of trigeminal neuralgia at different temperatures through foramen rotundus.

Am J Transl Res 2021 15;13(4):3102-3110. Epub 2021 Apr 15.

Department of Pain Management, Shanghai Pudong Hospital, Fudan University Pudong Medical Center Shanghai, China.

Objective: To compare the efficacy and safety of CT-guided radiofrequency therapy in the treatment of trigeminal neuralgia (TN) through foramen rotundus at different temperatures.

Methods: A total of 60 patients with TN in our hospital were selected and randomly divided into the control group and the observation group, with 30 cases in each group. CT or MRI was routinely performed before the operation to exclude intracranial space-occupying lesions. The round hole of both groups of patients was targeted under CT guidance. The puncture needle position and depth were determined according to CT images and radiofrequency electrical stimulation. The control group gradually increased the radiofrequency temperature to 75°C, and the observation group gradually increased to 90°C for damage treatment. Both groups of patients were treated with radiofrequency for 360 s. The clinical efficacy was evaluated by BNI classification criteria. At the same time, the visual analog scale (VAS) score, the total score of Pittsburgh sleep quality index (PSQI) and the incidence of complications were compared between the two groups. The Kaplan-Meier method in survival analysis was used to calculate the pain recurrence rate at 1 and 2 years after the operation.

Results: One week after the operation, there was no significant difference in the total effective rate between the two groups (χ=0.089, P=0.766). After 2 months, the total effective rate of the observation group was higher than that of the control group (χ=4.043, P=0.044). One day and one week after the operation, the VAS score of the observation group was higher than that of the control group (t=7.365, 6.269; P=0.007, 0.012), and the total score of PSQI was significantly higher than that of the control group (t=8.026, 5.447; P=0.002, 0.015). There was no significant difference in VAS score and PSQI total score between the two groups 1 month and 2 months after operation (P>0.05). There was no significant difference in the incidence of postoperative complications between the two groups (P>0.05). Kaplan-Meier survival analysis was used to calculate the recurrence rate of pain at 1 and 2 years after operation. The recurrence rate of the observation group was significantly lower than that of the control group (χ=4.219, 4.021; P=0.039, 0.044).

Conclusion: CT-guided radiofrequency at 90°C through foramen rotundus is effective in the treatment of trigeminal neuralgia without increasing the incidence of complications.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8129275PMC
April 2021

Microgel-Stabilized Hydroxypropyl Methylcellulose and Dextran Water-in-Water Emulsion: Influence of pH, Ionic Strength, and Temperature.

Langmuir 2021 05 29;37(18):5617-5626. Epub 2021 Apr 29.

Department of Nutrition & Food Science, University of Maryland, College Park, Maryland 20742, United States.

A stable water-in-water (W/W) emulsion was formed by mixing dextran and hydroxypropyl methylcellulose (HPMC) with addition of β-lactoglobulin (Blg) microgels. The microstructure and stability of the W/W emulsion were investigated under different conditions. The microgels accumulating at the liquid-liquid interface led to a stable emulsion at pH 3-5, where the microgels carried positive charges. When the pH was increased above the pI of microgels (∼pH 5), the emulsion was destabilized because the microgels tended to stay in the continuous phase (i.e., dextran) rather than at the interface. The HPMC-in-dextran emulsions were stable under ionic strength levels up to 300 mM. The HPMC-in-dextran emulsion stabilized by Blg microgels was thermally stable, and the heat treatment promoted partial Blg microgel particle-particle fusion on the surface of HPMC droplets at 90 °C. Electrostatic and hydrophobic interactions between dextran and HPMC phase were further investigated to understand the microgels' accumulation at the liquid-liquid interface.
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http://dx.doi.org/10.1021/acs.langmuir.1c00484DOI Listing
May 2021

Controlling the secondary assembly of porous anionic uranyl-organic polyhedra through organic cationic templates.

Dalton Trans 2021 Apr 29;50(13):4499-4503. Epub 2021 Mar 29.

Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.

Herein, we report a new uranyl-organic polyhedron UL (L = BTPCA) assembled from uranyl and a semirigid tritopic ligand. By adjusting the carbon chain length of organic templates, two complexes can be obtained based on the diverse secondary assembly of UL cages. The mechanism of different arrangements of UL cages induced by organic templates was explored in detail.
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http://dx.doi.org/10.1039/d1dt00289aDOI Listing
April 2021

Temperature-Triggered Structural Dynamics of Non-Coordinating Guest Moieties in a Fluorescent Actinide Polyrotaxane Framework.

Chemistry 2021 Jun 21;27(34):8730-8736. Epub 2021 May 21.

Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, P. R. China.

We present here the synthesis of a novel fluorescent actinide polyrotaxane compound URCP1 through the utilization of an end-cutting pseudorotaxane precursor with only the cucurbit[6]uril (CB[6]) macrocyclic components acting as linking struts. The non-coordinating guest motif in the obtained polyrotaxane, with increased freedom and structural flexibility, can display intriguing temperature-triggered conformational variations inside the cavity of CB[6], which was clearly evidenced by crystallographic snapshots at different temperatures. Notably, this observation of temperature-triggered structural dynamics in URCP1 represents the first report of actinide polyrotaxane with such feature in solid-state. Moreover, URCP1 has a high photoluminescence quantum yield (PLQY) of 49.8 %, comparable to other luminescent uranyl compounds, and can work as a fluorescent probe to selectively detect Fe over other eight competing cations in aqueous solution, with the limit of detection being as low as 4.4×10  ppm.
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http://dx.doi.org/10.1002/chem.202100614DOI Listing
June 2021

An integrated assessment methodology for management of potentially contaminated sites based on public data.

Sci Total Environ 2021 Aug 6;783:146913. Epub 2021 Apr 6.

Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China. Electronic address:

Ranking assessment of potentially contaminated sites (PCS) provides a great quantity of information (namely the risk screening list) that is usually examined by environmental managers, and therefore reduces the cost of risk management in terms of site investigation. Here we propose an integrated assessment methodology to establish a risk screening list of PCS in China using the Choquet integral correlation coefficient (ICC), which takes the uncertainty and interaction of PCS attributes into explicit account. The proposed method globally considers the importance and ordered positions of PCS attributes while reflecting their overall ranking. The model evaluation and actual validation results demonstrate the success in PCS ranking by the proposed method, which is superior to other methods such as the intuitionistic fuzzy multiple attribute decision-making, the technique for order preference by similarity to an ideal solution, and the weighted average. The resulting spatial distribution of Choquet ICC indicates that high-attention PCS in China are mainly located in Guangdong, Jiangsu, Zhejiang, and Shandong Provinces. This study is the first attempt to conduct a ranking assessment of PCS across China. The proposed assessment method based on Choquet ICC offers a step towards establishing a risk screening list of PCS globally.
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http://dx.doi.org/10.1016/j.scitotenv.2021.146913DOI Listing
August 2021

Ellagic acid solid dispersion: Characterization and bioactivity in the hydroxyl radical oxidation system.

Food Res Int 2021 04 1;142:110184. Epub 2021 Feb 1.

College of Food Science and Technology, Hainan Tropical Ocean University, Sanya 572022, China; National Engineering Laboratory of Intelligent Food Technology and Equipment, Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Key Laboratory for Agro- Products Nutritional Evaluation of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Fuli Institute of Food Science, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China. Electronic address:

Ellagic acid solid dispersion (EASD) was prepared using polyvinylpyrrolidone (PVP) as a carrier to improve its solubility. The solubility of EASD enhanced to 0.593 mg/mL, more than 20 times of the solubility on pure EA. The structure of EASD was analyzed by UV-visible spectroscopy, Fourier transforms infrared spectrometer (FT-IR) and X-ray diffraction (XRD), and results indicated the successful preparation of EASD, with a decrease in crystallinity. Differential scanning calorimetry (DSC) spectrums showed a lower endothermic peak of EASD than EA. By antioxidant analysis, the EASD with the concentration of 3 mg/mL was used in the protein oxidation analysis in hydroxyl radical oxidation simulation system, which was established by the myofibrillar of hairtail. EASD exhibited an excellent inhibit effect on protein oxidation. By increasing the solubility, EASD broadens the application range of EA, providing a theoretical basis for its application in the preservation of aquatic products.
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http://dx.doi.org/10.1016/j.foodres.2021.110184DOI Listing
April 2021

[Heavy Metal Contents of Soil and Surface Dust and Its Ecological Risk Analysis in a Multifunctional Industrial Park].

Huan Jing Ke Xue 2021 Mar;42(3):1105-1113

Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.

A multifunctional industrial park can perform both producing and living functions. The smelting and processing of non-ferrous metals may lead to soil pollution, posing risks to human beings. In this study, an industrial park located in central Anhui Province, China, with copper (Cu) processing and mechanical components as the main industries, was selected as the study object. By collecting and testing soil and dust samples, the horizontal and vertical distribution characteristics of heavy metals in soil and dust in the park were analyzed. The ecological risk index is used to identify areas with higher risks and correlation and principal component analysis are used to disclose the potential source of heavy metals. Results showed that the contents of Cu, Zn, As, Pb, and Cd in the soil were 2.65, 1.76, 1.56, 2.14, and 3.87 times that of the background value, respectively. The heavy metal content of dust was significantly higher than that of soil, with contents of Cr, Ni, Cu, Zn, Hg, As, Pb, and Cd of 1.93, 1.05, 7.57, 4.63, 6.08, 5.39, 2.58, and 5.50 times that of the background value, respectively. Horizontally, the areas with higher ecological risks concentrated in the western part of the park, while vertically there was no significant trend with increases in soil depth. For the dust samples, areas with high ecological risks were closer to the main traffic arteries. Principal component analysis indicated that the main source of heavy metal in western soils was probably irrigation with contaminated river water. Road traffic, on the other hand, is more likely to be the main contributor to high dust heavy metal levels. This result is important for the park to control the potential health risks caused by heavy metals through zoning management according to the functions of different areas.
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http://dx.doi.org/10.13227/j.hjkx.202010267DOI Listing
March 2021

[Analysis of the Spatial Distribution of Heavy Metals in Soil from a Coking Plant and Its Driving Factors].

Huan Jing Ke Xue 2021 Mar;42(3):1081-1092

Institute of Geographic Science and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.

Coking plants are typical industrial pollution sites and may release heavy metals into the environment, posing a threat to human health. Scholars have discovered that different types of heavy metals are released during different coking production processes and lead to spatial differences in heavy metals. Research on the spatial distribution and driving factors of pollutants in the soil inside and outside coking plants is important for sampling design, risk assessment, pollution prevention and control, etc.. Inverse distance weight was used to analyze the spatial distribution of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn inside and outside of the coking plant. A geo-detector was used to find out the difference in the driving factors for the spatial distribution of heavy metals between soil from inside and outside the coking plant. The results showed that except As, Ni, and Zn, the overall background value rate of other heavy metals was above 50%, and the continuity of the spatial distribution of heavy metals in the soil was poor. The coefficient of variation (CV) exceeded 30%, representing a moderate variation. The average degree of CV inside the coking plant was Hg > Cd > As > Cu > Zn > Cr > Pb > Ni, and the external average degree of CV was Hg > Cu > Cd > As > Zn > Pb > Cr > Ni. An analysis of heavy metal content showed that the content of As, Cd, Cr, Pb, and Zn outside the coking plant was bigger than inside. According to geo-detector results, the physicochemical properties factors with a large contribution rate to the spatial distribution of heavy metals inside and outside the coking plant was the soil's total nitrogen, organic matter, and available medium-micro element content. Pollution source factors that contributed the most to the spatial distribution of heavy metals inside were the crude benzol and cold drum section, while the coke oven and quench section determined the outside spatial distribution of heavy metals. The value of the strongest factor inside the coking plant was more than 0.5 while outside the coking plant it was less than 0.5. According to the interaction detector result, the interaction factors values of pollution sources and soil physicochemical properties to the inside spatial distribution of heavy metals was higher than outside. According to the distribution and geo-detector results, the strongest physicochemical properties driving factors that determined the inside and outside spatial distribution of heavy metals were relatively consistent. These factors were soil nutrient factors, which mainly influenced the availability of heavy metals. The differences in the production processes led to the difference between the inside and outside spatial distribution of heavy metals. The content of heavy metals outside the coking plant was higher than inside because the heavy metals came from various pollution sources. The driving forces for the distribution of heavy metals inside the plant were higher than outside and showed that the heavy metals inside of the plant were mainly from the coking plant. Heavy metal distribution inside the coking plant was mainly driven by the pollution source factor of the coking refining process and coking water, while heavy metal distribution outside the coking plant was mainly driven by the coking gas production process and other emission pollution source factors.
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http://dx.doi.org/10.13227/j.hjkx.202008218DOI Listing
March 2021

An integrated method for source apportionment of heavy metal(loid)s in agricultural soils and model uncertainty analysis.

Environ Pollut 2021 May 5;276:116666. Epub 2021 Feb 5.

Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China.

Elevated concentrations of heavy metals in agricultural soils threatening ecological security and the quality of agricultural products, and apportion their sources accurately is still a challenging task. Multivariate statistical analysis, GIS mapping, Pb isotopic ratio analysis (IRA), and positive matrix factorization (PMF) were integrated to apportion the potential sources of heavy metal(loid)s of orchard soil in Karst-regions. Study region soils were moderately contaminated by Cd. Obvious enrichment and moderate contamination level of Cd were found in study region surface soils, followed by As, Zn, and Pb. Correlation analysis (CA) and principal component analysis (PCA) indicated Ba, Co, Cr, Ni, V were mainly from natural sources, while As, Cd, Cu, Pb, Zn were derived from two kinds of anthropogenic sources. Based on Pb isotope composition, atmospheric deposition and livestock manure were the main sources of soil Pb accumulation. Further source identification and quantification results with PMF model and GIS mapping revealed that soil parent materials (46.44%) accounted for largest contribution to the soil heavy metal(loid)s, followed by fertilizer application (31.37%) and mixed source (industrial activity and manure, 22.19%). Uncertainty analysis indicated that the three-factors solution of PMF model was an optimal explanation and the heavy metal(loid) with lower percentage contributions had higher uncertainty. This study results can help to illustrate the sources of heavy metals more accurately in orchard agricultural soils with a clear expected future for further applications.
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http://dx.doi.org/10.1016/j.envpol.2021.116666DOI Listing
May 2021

Uranyl-catalyzed hydrosilylation of -quinone methides: access to diarylmethane derivatives.

Org Biomol Chem 2021 Feb;19(7):1575-1579

Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, P. R. China.

An efficient and convenient uranyl-catalyzed reductive hydrosilylation reaction of para-quinone methides (p-QMs) was developed by employing silane as the reductant. The hydrosilylation procedure using the UO2(NO3)2·6H2O/Et3SiH catalytic system proceeded smoothly and provided an expedient method for the construction of various diarylmethane derivatives in one step with good to excellent yields.
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http://dx.doi.org/10.1039/d0ob02455dDOI Listing
February 2021

High-Temperature Synthesis of a Uranyl Peroxo Complex Facilitated by Hydrothermally In Situ Formed Organic Peroxide.

Inorg Chem 2021 Feb 26;60(4):2133-2137. Epub 2021 Jan 26.

Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.

Because HO is thermally unstable, it seems to be difficult to synthesize peroxides at elevated temperatures. We describe here the in situ generation of peroxide that is incorporated in a new uranyl peroxo complex, HT-UPO1, through the hydrothermal treatment of uranyl nitrate at 150 °C in the presence of organic ligands. In this novel process, a highly conjugated aromatic carboxylate linker, ()-4-[2-(pyridin-4-yl)vinyl]benzoic acid (H), plays a crucial role by inducing the reduction of oxygen in air to form peroxide in situ and coordinating with uranyl to promote the preferred formation of thermally stable HT-UPO1. This work expands our knowledge on the speciation and chemistry of uranyl peroxide compounds and also sheds light on the possibility of their synthesis under more harsh conditions.
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http://dx.doi.org/10.1021/acs.inorgchem.0c03661DOI Listing
February 2021

Potassium Ions Induced Framework Interpenetration for Enhancing the Stability of Uranium-Based Porphyrin MOF with Visible-Light-Driven Photocatalytic Activity.

Inorg Chem 2021 Jan 31;60(2):651-659. Epub 2020 Dec 31.

Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China.

The stability of many MOFs is not satisfactory, which severely limits the exploration of their potential applications. Given this, we have proposed a strategy to improve the stability of MOFs by introducing alkali metal K capable of coordinating with metal nodes, which finally induces the interpenetrating uranyl-porphyrin framework to connect as a whole (). The stability experiments reveal that the has good thermal stability up to 400 °C and can maintain its crystalline state in the aqueous solution with pH ranging from 2 to 11. The catalytic activity of as a heterogeneous photocatalyst for CO cycloaddition under the driving of visible light at room temperature is also demonstrated. This induced interpenetration and fixation method may be promising for the fabrication of more functional MOFs with improved structural stability.
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http://dx.doi.org/10.1021/acs.inorgchem.0c02473DOI Listing
January 2021

Alkynyl silver modified chitosan and its potential applications in food area.

Carbohydr Polym 2021 Feb 21;254:117416. Epub 2020 Nov 21.

Department of Nutrition and Food Science, College of Agriculture and Natural Resources, University of Maryland, College Park, MD 20742, United States. Electronic address:

Chitosan was modified by substituting alkynyl silver on chitosan (Ag-CS) through a two-step chemical modification to form a novel antimicrobial coating material. The physicochemical property, antimicrobial activity, cytotoxicity, and potential food applications of Ag-CS were systematically investigated. The Ag-CS presented a smooth sheet structure, and demonstrated stronger antimicrobial effects than either silver acetate (AgOAc) or silver nitrate (AgNO) against both Gram positive and Gram negative bacteria strains. Ag-CS also demonstrated a controlled release of Ag for over 5 days, whereas AgOAc or AgNO infused chitosan released over 90 % Ag within 4 h. Ag-CS coating on shrimps significantly extended their shelf-life. Overall, our results revealed that the newly developed Ag-CS antimicrobial coating material possesses strong antimicrobial efficacies with a sustained Ag release property, and its ability to slow down the spoilage rate of shrimps indicates its potential in the improvement of food quality and shelf life.
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http://dx.doi.org/10.1016/j.carbpol.2020.117416DOI Listing
February 2021

Effective strategy to recycle arsenic-accumulated biomass of Pteris vittata with high benefits.

Sci Total Environ 2021 Feb 2;756:143890. Epub 2020 Dec 2.

Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China. Electronic address:

Recycling the arsenic-rich biomass of Pteris vittata is a critical problem during phytoremediation primarily because of the low value and high risk of arsenic-rich biomass. Nevertheless, extracts of P. vittata have been found to have a variety of bio-activities (e.g., anti-oxidation, anti-cancer, and anti-bacterial) and abundant valuable bio-active compositions (e.g., flavonoids), which might present a new solution for the recycling of P. vittata harvests. This work demonstrated a pilot-scale experiment to extract and purify the phenolic compounds from 1 t of arsenic-rich P. vittata biomass. Result showed that 47.9 kg of phenolic-rich extract with a potential value of US$908.66-8345.14 was obtained. This extract showed no acute oral toxicities (LD > 10 g/kg), no skin irritation, and no chronic risks in the long-term skin contact exposure pathways. All of the wastes from production have been recycled and safely disposed with low cost (US$28.44), and the cost may be further reduced. The calculated benefits from this method showed a potential to provide 995-53,050 US$/hm per year to a phytoremediation project. Therefore, this strategy could address the issue of expensive phytoremediation.
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http://dx.doi.org/10.1016/j.scitotenv.2020.143890DOI Listing
February 2021

The bio-availability and accumulation of the trace elements in rock-soil-fruit system in carbonatite regions of different stratums: Critical soil factors and transfer models.

Sci Total Environ 2021 Mar 4;760:143328. Epub 2020 Nov 4.

Center for Environmental Remediation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.

For exploring the key factors affecting trace element accumulation in crops in limestone soil derived from limestone area of different stratums, the loquat (Eriobotrya japonica Lindl.) orchard of three limestone units (Middle Devonian, Upper Devonian and Middle Cambrian) in Mengzi city of Yunnan Province, China were investigated. Loquat fruits grown on soil from Middle Devonian limestone exhibited significantly higher bio-enrichment in cadmium. The Middle Devonian (Chemical Index of Alteration [CIA] = 86.07) and Upper Devonian (CIA = 84.84) soils were more weathered than those derived from Middle Cambrian rocks (CIA = 74.42). In the Middle Devonian limestone area, Fe element (for As uptake into fruit), Al element (for Cu and Zn) and metal speciation (for Cd, extracted by diethylene triamine pentaacetic acid) in the soil were the important influencing factors. For the Upper Devonian, soil weathering was found to be the key factors controlling fruit Cu uptake, respectively. For the Middle-Cambrian-derived soils, soil Ca concentration and pH played a critical role in Cd accumulation in fruit. In conclusion, under acidic soil conditions derived from limestone, the Ca concentration and metal fraction in the soil are the pivotal factors affecting Cd accumulation of fruit, whereas the soil Fe element content control the fruit As and Pb uptake. These results are helpful to further understand the migration regularity of trace elements into fruit in different limestone geology types.
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http://dx.doi.org/10.1016/j.scitotenv.2020.143328DOI Listing
March 2021

Auxiliary Ligand-Dependent Adaptive Regulation of Uranyl Coordination in Mixed-Ligand Uranyl Compounds of Flexible Biphenyltetracarboxylic Acid.

Inorg Chem 2020 Dec 13;59(23):17659-17670. Epub 2020 Nov 13.

Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.

The mixed-ligand strategy is one of the important methods for preparing new materials and regulating the properties of materials. In this work, by introducing different auxiliary ligands (ALs), we have obtained a series of mixed-ligand uranyl complexes (-) from a flexible biphenyltetracarboxylic acid (Hbptc) with an adjustable orthogonal conformation and studied the influence of different organic base molecules on the coordination and assembly of Hbptc with a uranyl cation. It is found that the coordinated ALs, including 4,4'-bipyridine-1,1'-dioxide and 1,10-phenanthroline, partially occupy the coordination sites of the uranyl center and directly affect the molecular conformations and uranyl coordination of flexible bptc linkers. On the other hand, noncoordinated ALs such as protonated 4,4'-bipyridine ([H(4,4'-bpy)]) or dimethylammonium, which work as counterions in the form of encapsulated guests or hydrogen-bonded templates, also have a nonnegligible impact on the conformation and coordination of bptc linkers. Most interestingly, the AL-mediated evolution of uranyl coordination by the bptc linker and coordination geometry of the uranyl center is clearly observed, which suggests the adaptability of flexible bptc linkers to take suitable molecular configurations and uranyl coordination modes so as to adapt to the external regulator agents and varying environment. The physicochemical characterization of these uranyl compounds, especially photoluminescence, is addressed and discussed, and the results reveal that compound has the potential to serve as a multifunctional radiation detection material for UV light and X-ray radiation.
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http://dx.doi.org/10.1021/acs.inorgchem.0c02904DOI Listing
December 2020

Construction of Hybrid Bimetallic Uranyl Compounds Based on a Preassembled Terpyridine Metalloligand.

Chemistry 2021 Jan 30;27(6):2124-2130. Epub 2020 Dec 30.

Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, P. R. China.

Six hybrid uranyl-transition metal compounds [UO Ni(cptpy) (HCOO) (DMF)(H O)] (1), [UO Ni(cptpy) (BTPA) ] (2), [UO Fe(cptpy) (HCOO) (DMF)(H O)] (3), [UO Fe(cptpy) (BTPA) ] (4), [UO Co(cptpy) (HCOO) (DMF)(H O)] (5), and [UO Co(cptpy) (BTPA) ] (6), based on bifunctional ligand 4'-(4-carboxyphenyl)-2,2':6',2''-terpyridine (Hcptpy) are reported (H BTPA = 4,4'-biphenyldicarboxylic acid). Single-crystal XRD revealed that all six compounds feature similar metalloligands, which consist of two cptpy anions and one transition metal cation. The metalloligand M(cptpy) can be considered to be an extended linear dicarboxylic ligand with length of 22.12 Å. Compounds 1, 3, and 5 are isomers, and all of them feature 1D chain structures. The adjacent 1D chains are connected together by hydrogen bonds and π-π interactions to form a 3D porous structure, which is filled with solvent molecules and can be exchanged with I . Compounds 2, 4, and 6 are also isomers, and all of them feature 2D honeycomb (6,3) networks with hexagonal units of dimensions 41.91×26.89 Å, which are the largest among uranyl compounds with honeycomb networks. The large aperture allows two sets of equivalent networks to be entangled together to result in a 2D+2D→3D polycatenated framework. Remarkably, these uranyl compounds exhibit high catalytic activity for cycloaddition of carbon dioxide. Moreover, the geometric and electronic structures of compounds 1 and 2 are systematically discussed on the basis of DFT calculations.
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http://dx.doi.org/10.1002/chem.202004344DOI Listing
January 2021

MgrA Activates Staphylococcal Capsule via SigA-Dependent Promoter.

J Bacteriol 2020 12 18;203(2). Epub 2020 Dec 18.

Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA

capsule polysaccharide is an important antiphagocytic virulence factor. The genes are regulated at the promoter element (P) upstream of the operon. P, which consists of a dominant SigB-dependent promoter and a weaker upstream SigA-dependent promoter, is activated by global regulator MgrA. How MgrA activates capsule is unclear. Here, we showed that MgrA directly bound to the P region and affected the SigA-dependent promoter. Interestingly, an electrophoretic mobility shift assay showed that MgrA bound to a large region of P, mainly downstream of the SigA-dependent promoter. We further showed that the ArlRS two-component system and the Agr quorum sensing system activated capsule primarily through MgrA in the early growth phases. The virulence of depends on the expression of various virulence factors, which is governed by a complex regulatory network. We have been using capsule as a model virulence factor to study virulence gene regulation in MgrA is one of the regulators of capsule and has a major effect on capsule production. However, how MgrA regulates capsule genes is not understood. In this study, we were able to define the mechanism involving MgrA regulation of capsule. In addition, we also delineated the role of MgrA in capsule regulatory pathways involving the key virulence regulators Agr and Arl. This study further advances our understanding of virulence gene regulation in , an important human pathogen.
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http://dx.doi.org/10.1128/JB.00495-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7950413PMC
December 2020

Actinide Separation Inspired by Self-Assembled Metal-Polyphenolic Nanocages.

J Am Chem Soc 2020 09 21;142(39):16538-16545. Epub 2020 Sep 21.

Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.

The separation of actinides has a vital place in nuclear fuel reprocessing, recovery of radionuclides, and remediation of environmental contamination. Here we propose a new paradigm of nanocluster-based actinide separation, namely, nanoextraction, that can achieve efficient sequestration of uranium in an unprecedented form of giant coordination nanocages using a cone-shaped macrocyclic pyrogallol[4]arene as the extractant. The U-based hexameric pyrogallol[4]arene nanocages with distinctive [U(PG)] binuclear units (PG = pyrogallol) that rapidly assembled in situ in monophasic solvent were identified by single-crystal X-ray diffraction, MALDI-TOF mass spectrometry, NMR spectroscopy, and small-angle X-ray and neutron scattering. Comprehensive biphasic extraction studies showed that this novel separation strategy has enticing advantages such as fast kinetics, high efficiency, and good selectivity over lanthanides, thereby demonstrating its potential for efficient separation of actinide ions.
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http://dx.doi.org/10.1021/jacs.0c08048DOI Listing
September 2020

Visible-Light-Enabled C-H Functionalization by a Direct Hydrogen Atom Transfer Uranyl Photocatalyst.

Chemistry 2020 Dec 3;26(69):16521-16529. Epub 2020 Nov 3.

Laboratory of Nuclear Energy Chemistry, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, P.R. China.

The development of the uranyl cation as a powerful photocatalyst is seriously delayed in comparison with the advances in its fundamental and structural chemistry. However, its characteristic high oxidative capability in the excited state ([UO ] * (+2.6 V vs. SHE; SHE=standard hydrogen electrode) combined with blue-light absorption (hv=380-500 nm) and a long-lived fluorescence lifetime up to microseconds have reveals that the uranyl cation approaches an ideal photocatalyst for visible-light-driven organic transformations. Described herein is the successful use of uranyl nitrate as a photocatalyst to enable C(sp )-H activation and C-C bond formation through hydrogen atom transfer (HAT) under blue-light irradiation. In particular, this operationally simple strategy provides an appropriate approach to the synthesis of diverse and valuable diarylmethane motifs. Mechanistic studies and DFT calculations have provided insights into the detailed mechanism of the photoinduced HAT pathway. This research suggests a general platform that could popularize promising uranyl photocatalytic performance.
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http://dx.doi.org/10.1002/chem.202003431DOI Listing
December 2020
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