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The insufficient antioxidant reserves in tumor cells play a critical role in reactive oxygen species (ROS)-mediated therapeutics. Metallothionein-2 (MT-2), an intracellular cysteine-rich protein renowned for its potent antioxidant properties, is intricately involved in tumor development and correlates with a poor prognosis. Consequently, MT-2 emerges as a promising target for tumor therapy. Herein, we present the development of copper-doped carbon dots (Cu-CDs) to target MT-2 to compromise the delicate antioxidant reserves in tumor cells. These Cu-CDs with high tumor accumulation and prolonged body retention can effectively suppress tumor growth by inducing oxidative stress. Transcriptome sequencing unveils a significant decrease in MT-2 expression within the in vivo tumor samples. Further mechanical investigations demonstrate that the antitumor effect of Cu-CDs is intricately linked to apolipoprotein E (ApoE)-mediated downregulation of MT-2 expression and the collapse of the antioxidant system. The robust antitumor efficacy of Cu-CDs provides invaluable insights into developing MT-2-targeted nanomedicine for cancer therapies.

Cyclic peptide natural products represent an important class of bioactive compounds and clinical drugs. Enzymatic side-chain macrocyclization of ribosomal peptides is a major strategy developed by nature to generate these chemotypes, as exemplified by the superfamily of ribosomally synthesized and post-translational modified peptides. Despite the diverse types of side-chain crosslinks in this superfamily, the participation of histidine residues is rare. Herein, we report the discovery and biosynthesis of bacteria-derived tricyclic lanthipeptide noursin, which is constrained by a tri amino acid labionin crosslink and an unprecedented histidine-to-butyrine crosslink, named histidinobutyrine. Noursin displays copper-binding ability that requires the histidinobutyrine crosslink and represents the first copper-binding lanthipeptide. A subgroup of lanthipeptide synthetases, named LanKC Hbt , were identified to catalyze the formation of both the labionin and the histidinobutyrine crosslinks in precursor peptides and produce noursin-like compounds. The discovery of the histidinobutyrine-containing lanthipeptides expands the scope of post-translational modifications, structural diversity and bioactivity of ribosomally synthesized and post-translational modified peptides., (© 2023. The Author(s).)

In this study, the F-CuNPs were synthesized by a modified liquid-phase chemical reduction method. Throughout the preparation process, anhydrous copper sulfate was used as the copper source, and ascorbic acid in the NaOH solution served as the reducing and protective agent. Förster resonance energy transfer (FRET) may exist between F-CuNPs and vitamin B2 due to the large spectral overlap between the fluorescence emission spectra of F-CuNPs and the UV-vis absorption spectra of vitamin B2. Therefore, the detection of vitamin B2 was designed based on a FRET system between F-CuNPs and vitamin B2. With S 2- into the F-CuNPs&VB2 system, the fluorescence intensity of vitamin B2 was quenched, while the fluorescence intensity of F-CuNPs was almost unchanged. There may be a specific reaction between S 2- and vitamin B2. Therefore, the research system can be further used to detect S 2- based on ratiometric fluorescent probe. The research findings show that the linear range of vitamin B2 was 0.51 nM-34.64 nM with a detection limit of 0.25 nM (S/N = 3), the linear range of S 2- was 0.64 μM-60.00 μM with a detection limit of 0.32 μM (S/N = 3). Furthermore, the simultaneous fluorescent sensing system has high sensitivity and selectivity. Therefore, this system was designed and successfully used to detect the content of vitamin B2 and S 2- in actual samples to find a new effective method to detect analytes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In this work, the assembly between one-dimensional (1D) nanomaterials and two-dimensional (2D) nanomaterials was achieved by a simple method. Cuprous oxide nanowires decorated graphene oxide nanosheets (Cu 2 O@GO) nanocomposites were synthesized for the first time by a simple electrostatic self-assembly process. The nanostructure was well confirmed by scanning electron microscope (SEM) and transmission electron microscope (TEM) images. Taking advantages of good electrocatalytic activity and high specific surface area of Cu 2 O@GO nanocomposites, a label-free electrochemical immunosensor was developed by employing Cu 2 O@GO as signal amplification platform for the quantitative detection of alpha fetoprotein (AFP). In addition, toluidine blue (TB) was used as the electron transfer mediator to provide the electrochemical signal, which was adsorbed on graphene oxide nanosheets (GO NSs) by electrostatic attraction. The detection mechanism was based on the monitoring of the electrochemical current response change of TB by the square wave voltammetry (SWV) when immunoreaction occurred on the surface of electrode. Under optimal conditions, the proposed immunosensor displayed a high sensitivity and a low detection limit. This designed method may provide an effective method in the clinical diagnosis of AFP and other tumor markers., (Copyright © 2016 Elsevier B.V. All rights reserved.)

A disposable electrochemical immunosensor was developed for detection of aflatoxin B1 (AFB1) based on stripping voltammetric detection of copper ions released from Cu-apatite. AFB1 antibody (Ab) was firstly fixed on the gold nanoparticle (Au NPs) modified screen-printed carbon electrode (SPCE). AFB1-bovine serum albumin (AFB1-BSA) conjugate was labeled with Cu-apatite, and then competed with AFB1 for binding to the Ab. Copper ions were released from Cu-apatite through acidolysis and stripping voltammetry signal of the copper ions was used for the detection. The Cu-apatite increased the amount of loaded copper ions, and the anodic stripping strategy performed in the micro electrolytic cell of the SPCE simplified the detection procedure and further amplified the electrochemical signal. This immunosensor could detect AFB1 over a wide concentration range from 0.001 to 100ng mL(-1) with a detection limit of 0.2pg mL(-1). The low cost, high sensitive, rapid and accurate method may find widely potential application in the detection of other toxic or harmful substances., (Copyright © 2015 Elsevier B.V. All rights reserved.)

This study describes the exploitation of click chemistry in the one-step molecular engineering of an unqualified rhodamine probe, leading to its considerable functional enhancement in terms of water solubility, ion selectivity, and usefulness in detecting biological and environmental samples. A dipropargyl rhodamine dye previously identified as an unselective and poorly water-soluble mercury(II) probe was used to couple with an azido polyethylene glycol (PEG) by the Cu(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition click reaction in almost quantitative yield. The simple click-engineered rhodamine probe shows, remarkably, better water solubility and mercury(II) selectivity comparing to the raw counterpart, and can be used to sensitively image mercury ions internalized by live cells and to accurately quantify the ion spiked in river water specimens. This study provides insights into the simple functional improvement of unqualified molecular dye probes via the efficient "click engineering".

The Cu-based MOF loaded on macroporous carbon (MPC) creates novel Cu-MOF-MPC hybrids for the first time. The obtained Cu-MOF-MPC composites are used as electrocatalysts for the oxidation of NADH and reduction of H2O2 in neutral solution.

In recent decades, the antihyperglycemic biguanide metformin has been used extensively in the treatment of type 2 diabetes, despite continuing uncertainty over its direct target. In this article, using two independent approaches, we demonstrate that cellular actions of metformin are disrupted by interference with its metal-binding properties, which have been known for over a century but little studied by biologists. We demonstrate that copper sequestration opposes known actions of metformin not only on AMP-activated protein kinase (AMPK)-dependent signaling, but also on S6 protein phosphorylation. Biguanide/metal interactions are stabilized by extensive π-electron delocalization and by investigating analogs of metformin; we provide evidence that this intrinsic property enables biguanides to regulate AMPK, glucose production, gluconeogenic gene expression, mitochondrial respiration, and mitochondrial copper binding. In contrast, regulation of S6 phosphorylation is prevented only by direct modification of the metal-liganding groups of the biguanide structure, supporting recent data that AMPK and S6 phosphorylation are regulated independently by biguanides. Additional studies with pioglitazone suggest that mitochondrial copper is targeted by both of these clinically important drugs. Together, these results suggest that cellular effects of biguanides depend on their metal-binding properties. This link may illuminate a better understanding of the molecular mechanisms enabling antihyperglycemic drug action.

Rationale: Copper, an essential nutrient, has been implicated in vascular remodeling and atherosclerosis with unknown mechanism. Bioavailability of intracellular copper is regulated not only by the copper importer CTR1 (copper transporter 1) but also by the copper exporter ATP7A (Menkes ATPase), whose function is achieved through copper-dependent translocation from trans-Golgi network (TGN). Platelet-derived growth factor (PDGF) promotes vascular smooth muscle cell (VSMC) migration, a key component of neointimal formation., Objective: To determine the role of copper transporter ATP7A in PDGF-induced VSMC migration., Methods and Results: Depletion of ATP7A inhibited VSMC migration in response to PDGF or wound scratch in a CTR1/copper-dependent manner. PDGF stimulation promoted ATP7A translocation from the TGN to lipid rafts, which localized at the leading edge, where it colocalized with PDGF receptor and Rac1, in migrating VSMCs. Mechanistically, ATP7A small interfering RNA or CTR small interfering RNA prevented PDGF-induced Rac1 translocation to the leading edge, thereby inhibiting lamellipodia formation. In addition, ATP7A depletion prevented a PDGF-induced decrease in copper level and secretory copper enzyme precursor prolysyl oxidase (Pro-LOX) in lipid raft fraction, as well as PDGF-induced increase in LOX activity. In vivo, ATP7A expression was markedly increased and copper accumulation was observed by synchrotron-based x-ray fluorescence microscopy at neointimal VSMCs in wire injury model., Conclusions: These findings suggest that ATP7A plays an important role in copper-dependent PDGF-stimulated VSMC migration via recruiting Rac1 to lipid rafts at the leading edge, as well as regulating LOX activity. This may contribute to neointimal formation after vascular injury. Our findings provide insight into ATP7A as a novel therapeutic target for vascular remodeling and atherosclerosis.

Soil samples from 4 defined city zones of Nanjing were randomly collected at 0-5 cm and 5-20 cm intervals and size fractions of soil particles were separated from undisturbed bulk soils by low energy dispersion procedure. The total contents of Cu and Pb in the different particle size fractions of the urban soils were analyzed by HNO3-HF-HClO4 digestion and flame atomic absorption spectrophotometer determination. The total content of Cu and Pb in soil particle size fractions varied with their size and with city zones as well. Both the content and variation with the size fractions of Pb was bigger than of Cu supporting our previous finding that there was Pb pollution to different degrees in the urban soils although the two elements were generally enriched in clay-sized fraction. Contaminated Pb tended to be preferentially enriched in the size fraction of 2000-250 microm and clay-sized fraction. While the size fractions of the soils from newly developed and preserved area contained smaller amount of Cu and Pb, the partitioning of them in coarse and fine particle size fractions were insignificant compared to that from inner residence and commercial area. The very high Pb level over 150 mg/kg of the fine particle fractions from the soils of the inner city could be a cause of high blood Pb level reported of children from the city as acute exposure to Pb of fine particles of the urban soil might occur by soil ingestion and inhalation by young children. Thus, much attention should be paid to the partitioning of toxic metals in fine soil particles of the urban soils and countermeasures against high health risk of Pb exposure by soil ingestion and dust inhalation should be practiced against the health problem of blood Pb for young children from the cities.

Compared to traditional lithium metal batteries, anode-free lithium metal batteries use bare current collectors as an anode instead of Li metal, making them highly promising for mass production and achieving high-energy density. The current collector, as the sole component of the anode, is crucial in lithium deposition-stripping behavior and greatly impacts the rate of Li depletion from the cathode. In this study, to investigate the lithiophilicity effect of the current collector on the solid electrolyte interface (SEI) film construction and cycling performance of anode-free lithium batteries, various lightweight paper-based current collectors were prepared by electroless plating Cu and lipophilic Ag on low-dust paper (LDP). The areal densities of the as-prepared LDP@Cu, LDP@Cu-Ag, and LDP@Ag were approximately 0.33 mg cm−2. The use of lipophilic Ag-coated collectors with varying loadings allowed for the regulation of lipophilicity. The impacts of these collectors on the distribution of SEI components and Li depletion rate in common electrolytes were investigated. The findings suggest that higher loadings of lipophilic materials, such as Ag, on the current collector increase its lipophilicity but also lead to significant Li depletion during the cycling process in full-cell anode-free Li metal batteries. Thus, moderately lithiophilic current collectors, such as LDP@Cu-Ag, show more potential for Li deposition and striping and stable SEI with a low speed of Li depletion. [ABSTRACT FROM AUTHOR]

The parent HZSM-5 was modified with oxide M (M = Fe, Cu, La, P) via the incipient impregnation method by using ferric nitrate, copper nitrate, lanthanum nitrate and diammonium hydrogen phosphate as precursors to prepare a series of oxide M modified HZSM-5 (M/HZSM-5). And the M/HZSM-5 used as solid acid was physically mixed with commercial Cu/ZnO/Al2O3 to obtain bifunctional catalysts for steam reforming of dimethyl ether (SRD) reaction. The samples were systematically characterized by XRD, FTIR, N2 adsorption–desorption, and NH3-TPD techniques. The results showed that HZSM-5 structure remained basically unchanged after it was modified by oxide M; however, its specific surface area, pore volume, total acid amount, especially strong acid amount was decreased, and then affecting the DME conversion, H2 yield and carbon-containing product selectivity of the corresponding bifunctional catalyst. Among them, the bifunctional catalyst composed of Cu/ZnO/Al2O3 and La/HZSM-5 with the larger specific surface area and lower strong acid sites showed best SRD performance, and the dimethyl ether conversion and H2 yield reached 90.4% and 73.9% at TOS of 10 h under the conditions of reaction temperature 300 °C, pressure 0.1 MPa, space velocity 5000 mL/(g h), respectively. [ABSTRACT FROM AUTHOR]

This study proposes a straightforward strategy utilizing metal–organic frameworks (MOFs) to obtain efficient electrocatalysts for synthesizing C2 products (C2H4 and C2H5OH) via a CO2 reduction reaction. Cu-MOF-74 was chosen as the precursor, while copper oxide nanoparticles were obtained through a calcination method. During the calcination process, by controlling the calcination conditions, the porous structure of the MOF framework was successfully retained, leading to CuO-400 with a high catalytic activity and C2 production efficiency. Compared to CuO-n formed by the calcination of Cu(NO3)2, CuO-400 derived from MOFs exhibits a 1.6 times higher C2 activity as an electrocatalytic material at −1.15 V vs. RHE. [ABSTRACT FROM AUTHOR]

Cu-Co/X-MMT (X = Na, SiO2) catalysts were prepared via impregnation method using Na-MMT and SiO2-MMT (montmorillonite pillared by SiO2) as the support and copper nitrate and cobalt nitrate as precursors. In addition, the citric acid was introduced during the preparation of Cu-Co/SiO2-MMT to obtain Cu-Co/SiO2-MMT-Ac catalyst. The catalysts were characterized by XRD, TEM, H2-TPR, XPS and N2 adsorption–desorption at low temperature. The results showed that the acidity and specific surface area of SiO2-MMT were larger than those of Na-MMT, thus resulting in dimethyl ether (DME) conversion and H2 yield of Cu-Co/SiO2-MMT higher than those of Cu-Co/Na-MMT during steam reforming of DME (SRD). However, for Cu-Co/SiO2-MMT, there was a large amount of methanol in the carbon-containing product due to the large particle size of Cu. The Cu particle size of Cu-Co/SiO2-MMT-Ac was decreased significantly due to the introduction of citric acid, thus accelerating the steam reforming of methanol reaction and enabling the timely conversion of the intermediate product methanol of SRD, resulting in the increasing DME conversion and H2 yield. Therefore, Cu-Co/SiO2-MMT-Ac was expected to be a potential catalyst for SRD. [ABSTRACT FROM AUTHOR]

Herein, a novel self-supporting CuO/nickel-cobalt-sulfide (NCS) electrode was designed in a two-step electrodeposition technique followed by a calcination process. Three-dimensional copper foam (CF) was exploited as the current collector and spontaneous source for the in situ preparation of the CuO nanostructures, which ensured sufficient deposition space for the subsequent NCS layer, thus forming abundant electrochemical active sites. Such a hierarchical structure is conducive to providing a smooth path for promoting electronic transmission. Therefore, the optimized CuO/NCS electrode exhibits outstanding energy storage capability with extremely superior specific capacitance (Cs) of 7.08 F cm−2 at 4 mA cm−2 and coulombic efficiency of up to 94.83%, as well as excellent cycling stability with capacitance retention of 83.33% after 5000 cycles. The results presented in this work extend our horizons to fabricate novel hierarchical structured electrodes applied to energy storage devices. [ABSTRACT FROM AUTHOR]

Unlike transition metal oxides and sulfides, transition metal-based selenides display higher electrical conductivity, more electroactive unsaturated edge sites, and better chemical stability, which have found extensive usage in electrocatalysis. In this work, simple hydrothermal and solvothermal procedures were employed to synthesize quaternary (Ni, Co, Cu)Se2 nanosheet arrays on carbon cloth (CC) to measure glucose. The conductivity of the material can be effectively elevated by adding Se element to form selenides, and the synergistic effect between the three selenides can improve the electrocatalytic performance. Consequently, in the ranges of 0.01–600 μM and 600–9000 μM, respectively, the current response of the synthesized material to glucose concentration exhibited linear relationships. The sensor demonstrated excellent sensitivity and a low detection limit of 5.82 nM. Furthermore, the practical applicability of the constructed biosensor was proved by using it to quantify the amount of glucose in human serum. [ABSTRACT FROM AUTHOR]

Two inorganic–organic hybrid complexes based on bi-capped Keggin-type cluster, {([CuII(2,2′-bpy)2]2[PMoVI8VV2VIV2O40(VIVO)2])[CuI(2,2′-bpy)]}∙2H2O (1) and {[CuII(2,2′-bpy)2]2[SiMoVI8.5MoV2.5VIVO40(VIVO)2]}[CuI0.5(2,2′-bpy)(H2O)0.5] (2) (bpy = bipyridine), had been hydrothermally synthesized and structurally characterized by elemental analysis, FT-IR, TGA, PXRD and X-ray single-crystal diffraction analysis. Compound 1 consists of a novel 1-D chain structure constructed from [CuI(2,2′-bpy)]+ unit linking bi-supported POMs anion {[CuII(2,2′-bpy)2]2[PMoVI8VV2VIV2O40(VIVO)2]}−. Compound 2 is a bi-capped Keggin cluster bi-supported Cu-bpy complex. The main highlights of the two compounds are that Cu-bpy cations contain both CuI and CuII complexes. Furthermore, the fluorescence properties, the catalytic properties, and the photocatalytic performance of compounds 1 and 2 have been assessed, and the results show that both compounds are active for styrene epoxidation and degradation and adsorption of Methylene blue (MB), Rhodamine B (RhB) and mixed aqueous solutions. [ABSTRACT FROM AUTHOR]

Y-zeolites modified with copper ions (CuY) are adsorbents with great potential and economic value for the adsorption and separation of ethylene and ethane. However, there are still some problems that need to be solved, such as the relationship between the states of Cu species and the ethylene adsorption capacity. In this study, a series of CuNaY adsorbents with different loadings was prepared by a liquid phase ion exchange method. The Cu(I)NaY-3 adsorbent showed the most significant ethylene breakthrough adsorption capacity (2.14 mmol g−1). The location, valence, and dispersion of copper species in the CuNaY zeolites were comprehensively analysed by H2-TPR, in situ FTIR, HRTEM and XPS techniques. The experiments indicated that the adsorption capacity of ethylene depends on the states of the Cu species, which was also confirmed by DFT. These results can serve as a theoretical foundation and guideline for the development of highly efficient Cu-modified zeolite adsorbents for ethylene separation. [ABSTRACT FROM AUTHOR]

The development of a non‐noble metal cathode ORR catalyst with low cost, high activity and high stability has become an inevitable trend in MFC. The purpose of this study is to develop an efficient and stable Cu, N‐codoped porous carbons catalysts with multi‐pore structure for MFC. Herein, Cu, N‐codoped porous carbons materials (Cu−NC−T) with high N content and multi‐pore structure were successfully developed by co‐pyrolysis with MOF‐199 and melamine. By contrast, Cu‐doped porous carbon (Cu−C−T) without melamine was synthesized using MOF‐199 as template. The results showed that Cu−NC−T possessed a rough octahedral crystal with a unique multi‐mesopore structure with pore centers of 3.4 nm and 11.2 nm, respectively. Owing to high N content, abundantly exposed Cu−Nx active sites and the multi‐pore structure, Cu−NC−800 had a pronounced electrochemical ORR activity in neutral solution (onset potential and limiting current density were 0.161 V and −6.256 mA ⋅ cm−2), which were slightly lower than 20 wt % Pt/C (0.189 V and −6.479 mA ⋅ cm−2). Moreover, the MFC with Cu−NC−800 showed a power density of 662.8±3.6 mW ⋅ m−2, which was higher than that of Cu−C−800 (425.7±3.9 mW ⋅ m−2) and was slightly lower than that 20 wt % Pt/C (815.0±6.2 mW ⋅ m−2). The output voltage of MFC with Cu−NC−T had no obvious decreasing trend in 30 days, demonstrating that the Cu−NC−T had great stability. [ABSTRACT FROM AUTHOR]

Herein, nickel–cobalt sulfide (NCS) nanoflakes covering the surface of Cu(OH)2 nanorods were achieved by a facile two-step electrodeposition strategy. The effect of CH4N2S concentration on formation mechanism and electrochemical behavior is investigated and optimized. Thanks to the synergistic effect of the selected composite components, the Cu(OH)2/NCS composite electrode can deliver a high areal specific capacitance (Cs) of 7.80 F cm−2 at 2 mA cm−2 and sustain 5.74 F cm−2 at 40 mA cm−2. In addition, coulombic efficiency was up to 84.30% and cyclic stability remained 82.93% within 5000 cycles at 40 mA cm−2. This innovative work provides an effective strategy for the design and construction of hierarchical composite electrodes for the development of energy storage devices. [ABSTRACT FROM AUTHOR]

Chemodynamic therapy (CDT), which employs intracellular H 2 O 2 to produce toxic hydroxyl radicals to kill cancer cells, has received great attention due to its specificity to tumors. However, the relatively insufficient endogenous H 2 O 2 and the short-lifetime and limited diffusion distance of •OH compromise the therapeutic efficacy of CDT. Mitochondria, which play crucial roles in oncogenesis, are highly vulnerable to elevated oxidative stress. Herein, we constructed a mitochondria-mediated self-cycling system to achieve high dose of •OH production through continuous H 2 O 2 supply. Cinnamaldehyde (CA), which can elevate H 2 O 2 level in the mitochondria, was loaded in Cu(II)-containing metal organic framework (MOF), termed as HKUST-1. After actively targeting mitochondria, the intrinsic H 2 O 2 in mitochondria of cancer cells could induce degradation of MOF, releasing the initial free CA. The released CA further triggered the upregulation of endogenous H 2 O 2 , resulting in the subsequent adequate release of CA and the final burst growth of H 2 O 2. The cycle process greatly promoted the Fenton-like reaction between Cu2+ and H 2 O 2 and induced long-term high oxidative stress, achieving enhanced chemodynamic therapy. In a word, we put forward an efficient strategy for enhanced chemodynamic therapy. • A mitochondria-specific nanoreactor is constructed for chemodynamic therapy. • The self-cycling nanoreactor enables continuous supply of H 2 O 2 to produce ROS. • The uninterrupted oxidative damage of mitochondria achieves enhanced efficiency. [ABSTRACT FROM AUTHOR]

The CuCl‐catalyzed reaction of aryl boronic acid with carbon dioxide to form carboxylate ester after treatment with CH3I has been developed. The procedure featured mild conditions and good functional group tolerances. A diverse range of aryl boronic acids were effectively converted into carboxylate esters. Even those bearing sensitive groups such as carbonyl, ester, and amide could produce the desired products in good yields. [ABSTRACT FROM AUTHOR]

Herein, a Cu(OH)2/Ni3S2 composite was successfully prepared through facile two-step electrodeposition. As the electrode substrate and the only copper source, the copper foam underwent surface oxidation by galvanostatic deposition technology to form Cu(OH)2, and the subsequent coverage of Ni3S2 was achieved by potentiostatic deposition. The Cu(OH)2 acts as a skeleton, providing support for Ni3S2 growth, thus providing more abundant electrochemical active sites. By virtue of the in situ growth strategy and the synergy of different components, the optimized Cu(OH)2/Ni3S2 electrode illustrates significantly enhanced pseudocapacitance performance, with an areal specific capacitance of 11.43 F cm−2 at 2 mA cm−2, good coulombic efficiency of 94.55%, and remarkable cyclic stability (83.33% capacitance retention after 5000 cycles). [ABSTRACT FROM AUTHOR]

A copper‐catalyzed cascade synthesis of substituted 2‐aryl‐1H‐indoles from phenols and oximes is developed. This reaction involves dual C−H bond cleavage of phenols and cyclization with oximes and proceeds smoothly under mild conditions without any additives. [ABSTRACT FROM AUTHOR]

The synthesis of carbamates by electrocatalytic reduction of CO2 is an effective method to realize the utilization of CO2 resources. The development of high‐performance electrocatalysts to complete this process more efficiently is of great significance to sustainable development. Owing to their unique structural characteristics, single‐atom catalysts are expected to promote the reaction process more efficiently. In this study, an atomically dispersed Cu species on N‐doped carbon nanosheet composite material (Cu−N−C) was prepared by metal‐organic framework derivatization. Compared with traditional Cu bulk electrodes, the Cu−N−C material has better catalytic performance for the synthesis of methyl N‐phenylcarbamate; and the optimized yield reached 71 % at room temperature and normal pressure. The Cu−N−C material has good stability that the catalytic performance does not decrease after repeated use for 10 times. In addition, the Cu−N−C material has good applicability to this catalytic system, and a variety of amines can be smoothly converted into corresponding carbamates. [ABSTRACT FROM AUTHOR]

[Display omitted] • OVs-BMO composite with small sized Cu nanodots were synthesized. • The Cu/ILs/OVs-BMO highly increased the charge separation efficiency. • The amino-functionalized ILs increased the photocatalytic reduction of CO 2. The conversion of CO 2 into useful chemical fuels through solar photocatalysis is an important means to alleviate energy and environmental problems. In this work, small-sized Cu nanodots were dispersed on the surface of bismuth molybdate containing oxygen vacancies. The Cu/ILs/OVs-BMO composite photocatalyst with high photocatalytic reduction activity was obtained. The small size of Cu nanodots can not only greatly improve the visible light absorption of the composite catalyst, but also establish an effective channel for charge transport through the close interaction between Cu nanodots and bismuth molybdate, which promotes the efficient separation of photogenerated charge carriers and increases the photocurrent by 11.04 times. The CO 2 photocatalytic reduction interface reaction was improved by adding an amine-based functionalized ionic liquid. The complexation of ILs and CO 2 decreased the activation energy of generating CO 2 intermediate and the overpotential of the reaction. Compared with BMO, the yield of the liquid products on Cu/ILs/OVs-BMO photocatalyst increased by 17.80 times. [ABSTRACT FROM AUTHOR]

Abstract: Sodium (Na) metal is the most promising alternative for lithium metal as anode for the next‐generation energy storage systems. However, its practical implementation is hindered by the huge volume change and severe Na metal dendrite growth during electrochemical stripping/plating. Herein, the use of a chemically engineered porous copper (Cu) matrix as a stable host for metallic Na anode is presented. By treating the commercial Cu foam through a facile and cost‐effective method, a composite matrix consists of cylindrical core–shell skeleton is achieved, facilitating uniform impregnation and confinement of Na within the matrix pores promoted by the chemical interaction between Na and the matrix. The unique matrix's surface characteristic can divert the Na deposition from the skeleton towards the Na reservoirs within the pores, suppressing the volume change and mossy/dendritic Na growth. A stable Na cycling behavior is demonstrated in carbonate electrolyte without any additives at a high capacity up to 3 mAh cm−2 with a current density up to 2 mA cm−2. Moreover, electrochemical measurements of a full cell made of the Na composite matrix anode clearly reveal the superior performance at high rate (5C) over that using bare Na metal. [ABSTRACT FROM AUTHOR]

The Yangla copper deposit, with Cu reserves of 1.2 Mt, is located between a series of thrust faults in the Jinshajiang-Lancangjiang-Nujiang region, Yunnan, China, and has been mined since 2007. Fluid inclusion trapping conditions ranged from 1.32 to 2.10 kbar at 373-409 °C. Laser Raman spectroscopy confirms that the vapour phase in these inclusions consists of CO, CH, N and HO. The gas phases in the inclusions are HO and CO, with minor amounts of N, O, CO, CH, CH, CH, and CH. Within the liquid phase, the main cations are Ca and Na while the main anions are SO and Cl. The oxygen and hydrogen isotope compositions of the ore-forming fluids (−3.05‰ ≤ δO ≤ 2.5‰; −100‰ ≤ δD ≤ −120‰) indicate that they were derived from magma and evolved by mixing with local meteoric water. The δS values of sulfides range from −4.20‰ to 1.85‰(average on −0.85‰), supporting a magmatic origin. Five molybdenite samples taken from the copper deposit yield a well-constrained Re-Os isochron age of 232.8 ± 2.4 Ma. Given that the Yangla granodiorite formed between 235.6 ± 1.2 Ma and 234.1 ± 1.2 Ma, the Cu metallogenesis is slightly younger than the crystallization age of the parent magma. A tectonic model that combines hydrothermal fluid flow and isotope compositions is proposed to explain the formation of the Yangla copper deposit. At first, westward subduction of the Jinshajiang Oceanic Plate in the Early Permian resulted in the development of a series of thrust faults. This was accompanied by fractional melting beneath the overriding plate, triggering magma ascent and extensive volcanism. The thrust faults, which were then placed under tension during a change in tectonic mode from compression to extension in the Late Triassic, formed favorable pathways for the magmatic ore-forming fluids. These fluids precipitated copper-sulfides to form the Yangla deposit. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, using copper as an etching agent, a novel and easy method to prepare porous graphene nanosheet (P-GR) was reported. With a large number of pores, more acidic groups and edge defect sites (EDSs) compared with graphene (GR), the prepared P-GR was used as an electrochemical biosensing platform for the first time. Using voltammetry and amperometry as detection methods, some important electroactive compounds, including dopamine (DA), ascorbic acid (AA), uric acid (UA), epinephrine (EP), guanine (G), adenine (A), xanthine (XA), hypoxanthine (HX), hydrogen peroxide and β-nicotinamide adenine dinucleotide (NADH) were employed to study their electrochemical responses on P-GR modified glassy carbon electrode (P-GR/GCE). The results show that P-GR/GCE exhibits better electrochemical performance to these substances compared with GR modified glassy carbon electrode (GR/GCE) and edge plane pyrolitic graphite electrode (PGE). The remarkable electrochemical advantage of P-GR makes it a promising material in electrochemical biosensing field. [Copyright &y& Elsevier]

Porous hybrid Cu2O/polypyrrole nanoflakes have been synthesized from solid CuO nanoplate templates through the pyrrole-induced reductive transformation reaction at elevated temperature. The conversion mechanism involves the reductive transformation of CuO to Cu2O and the in situ oxidative polymerization of pyrrole to polypyrrole. In addition, the morphology of the as-converted nanohybrids depends on the shape of the CuO precursors. The strategy enables us to transform single-crystalline CuO nanosheets into hollow hybrid Cu2O/polypyrrole nanoframes. The ability to transform CuO and an organic monomer into porous hybrid materials of conducting polymer and Cu2O with macrosized morphological retention opens up interesting possibilities to create novel nanostructures. Electrochemical examinations show that these porous hybrid Cu2O/polypyrrole nanostructures exhibit efficient catalytic activity towards oxygen reduction reaction (ORR), excellent methanol tolerance ability, and catalytic stability in alkaline solution, thus making them promising nonprecious-metal-based catalysts for ORR in alkaline fuel cells and metal-air batteries. [ABSTRACT FROM AUTHOR]

morphous CoFeSiB wires with smooth surface and circular cross section were fabricated by melt extraction technology using a copper wheel with a knife-edge cross section angle of 60 deg. The effect of some process parameters such as wheel circumference velocity, molten alloy feed rate, and temperature on the geometry and weight, i.e., melt extracted layer thickness, of wire was examined carefully. An optimum process parameter to produce high-quality circular wires was presented. A high resolution CCD video camera recorder was used to monitor the changing of the surface shape of molten alloy contacting the wheel tip under different conditions. It was found that the mechanism of the wire formation during the optimum process condition was controlled by the momentum mechanism, while in the low wheel speed region, heat transfer turned out to be a dominant factor. Some characteristics of the circular wires such as amorphous nature and tensile strength were also studied. [ABSTRACT FROM AUTHOR]

It is necessary to study the validation of strength models under planar shock loading in view of the fact that strength models for metals obtained at moderate strain rates are often used in the numerical simulations of shock wave phenomena. The variations of longitudinal stress, transverse stress and yield strength of oxygen-free high conductance (OFHC) copper with time under planar shock loading are obtained by using the manganin stress gauges and compared with the predicted results by the constructed seven constitutive models based on Y/G=constant and on G/B=constant (Y the yield strength, G the shear modulus, B the bulk modulus), respectively. It seems that the pressure, density, temperature and plastic strain dependence of the yield strength for OFHC copper under planar shock loading is essential to the constitutive description. [ABSTRACT FROM AUTHOR]

Carbamates, carbon dioxide, copper, electrocatalysis, single-atom catalysts Cover Feature: Atomically Dispersed Copper on N-Doped Carbon Nanosheets for Electrocatalytic Synthesis of Carbamates from CO2 as a C1 Source (ChemSusChem 9/2021) Keywords: carbamates; carbon dioxide; copper; electrocatalysis; single-atom catalysts EN carbamates carbon dioxide copper electrocatalysis single-atom catalysts 1971 1971 1 05/08/21 20210506 NES 210506 B The Cover Feature b shows an atomically dispersed Cu species on N-doped carbon nanosheet composite material for electrocatalytic synthesis of carbamates using CO SB 2 sb under mild conditions. [Extracted from the article]

Critical impact velocity (CIV) of oxygen-free high-conductivity (OFHC) copper is experimentally measured with a novel facility in a gas gun system. The results are compared with the theoretical predictions using the typical constitutive relations, and the measured CIV value is much lower than the predictions. The difference of physical mechanisms in experiment and in theoretical calculation is discussed. It is suggested that the reduction of CIV in experiment would be related with the damage evolution in tensile copper that needs to be considered in the computation model. [ABSTRACT FROM AUTHOR]

Integration of separation and reaction, Ion exchange column, The copper()-hesperetin complex, Synthesis, Bioactivity. [Extracted from the article]

A novel high-speed tensile facility (HSTF) with special fixture is applied to research the dynamic failure characteristics of oxygen-free high-conductivity (OFHC) copper bars at different levels of strain. The experimental tests are numerically simulated involving void evolution. It is indicated that the localized strains at necking region computed with the adjusted Johnson--Cook model and the Zerilli--Armstrong model are consistent with the experimental results. [ABSTRACT FROM AUTHOR]

In this study, copper and phosphorus co-doped three-dimensional layered hexagonal cobalt nanodiscs were synthesized using a rapid and simple method and were applied for the detection of nitrobenzene, an environmental pollutant. The incorporation of phosphorus into the nanodiscs created catalytic sites, while the addition of copper increased the density of active sites and facilitated rapid charge transfer. Co-doping phosphorus and copper allowed the CuCo NDs/P composite material to exhibit excellent catalytic activity towards nitrobenzene. Experimental results demonstrated that CuCo NDs/P had a lower detection limit and a broader linear range. Additionally, the sensor was tested on natural water samples to evaluate its practical feasibility, indicating significant potential for further development. [Display omitted] • Three-dimensional layered hexagonal cobalt nanodiscs doped with Cu and P were synthesized. • The addition of P produced more catalytic sites, while the addition of Cu increased the density of active sites. • The CuCo NDs/P exhibit excellent catalytic activity against nitrobenzene. [ABSTRACT FROM AUTHOR]

Lead ions (Pb2+) are heavy metal ions that are harmful to living organisms and ecosystems. It is important to realize sensitive detection of Pb2+ in the environment. In this study, a signal enhancement photoelectrochemical (PEC) sensor with high sensitivity was constructed for the detection of Pb2+. Firstly, to obtain excellent electron transfer performance, sulfur defect–engineered Bi 2 S 3–x /In 2 S 3–y mediated signal enhancement formed by Bi 2 S 3 and In 2 S 3 with well–matched structure in terms of energy level as the substrate materials. In this case, the introduction of sulfur vacancies further affects the electronic structure of the material, which significantly improves the electrical conductivity and effectively increases the electron transfer rate. In addition, the as–synthesized Cu@Cu 2 O nanosphere is chosen as the marker to accelerate the electron transfer through the surface plasmon resonance effect of Cu. The constructed sensor was able to detect Pb2+ in the range of 1 ng mL−1–100 μg mL−1 with a limit of detection of 19.2 pg mL−1. The sensor exhibits good reproducibility, specificity, and stability, indicating such PEC sensor can achieve the sensitive detection of Pb2+ in the environment. This work paves a new way for the construction of PEC sensors and the specific PEC detection of Pb2+ in environmental waters. [Display omitted] • Bi 2 S 3-x /In 2 S 3-y containing sulfur vacancies as substrate materials. • The introduction of sulfur vacancies promotes electron transfer. • Cu@Cu 2 O nanospheres as labeling and SPR effect of Cu to accelerate electron transfer. • Pb2+ breaks the phosphodiester bond in the aptamer. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ternary heterojunction Bi 2 S 3 /Bi 2 O 3 /CdLa 2 S 4 improves carrier separation efficiency. • Bi 2 S 3 involved in the construction of heterojunctions and improve visible excitation. • Raspberry-like Cu 2 O nanosphere with higher electrochemically active areas as markers. • Sensitive detection of CA15-3 with a detection limit of 0.0003 U/mL. Sensitive detection of CA15-3 is important for postoperative monitoring and early diagnosis of breast cancer. In this work, a photoelectrochemical (PEC) biosensing platform was constructed of CA15-3 by using Bi 2 O 3 /CdLa 2 S 4 /Bi 2 S 3 ternary type-II heterojunction as the photoactive transduction material for sensitive detection, and the raspberry-shaped Cu 2 O nanospheres were exploited as the signal sensitizing tags. On one hand, the use of Bi 2 S 3 as a sensitizer can effectively enhance the visible light excitation of the substrate material. On the other hand, Bi 2 S 3 and Bi 2 O 3 /CdLa 2 S 4 have the ability to create dual type-II heterojunctions with matched energy levels, which significantly enhances the separation and migration efficiency of the photogenerated carriers and effectively suppresses the recombination of the e-/h+ pairs. Raspberry-like semiconducting Cu 2 O nanospheres can mediate the PEC process of the heterojunctions. An immunosensor was developed combining the signal transduction capacity of ternary heterojunction and the signal sensitizing effect of Cu 2 O nanospheres. The proposed PEC immunosensor showed good selectivity and stability for detecting CA15-3 (0.001 ∼ 100 U/mL) with a detection limit of 0.0003 U/mL (S/N = 3). The constructed PEC immunosensor had potential applications in the clinical detection of CA15-3, and was expected to play a great role in the early diagnosis of breast cancer in the future. Moreover, in the design engineering of photoactive materials, the improvement of visible excitation and the enhancement of carrier separation efficiency have been realized simultaneously using a single material, which provides new ideas for the design of photoactive materials. [ABSTRACT FROM AUTHOR]

Scheme 1. Mechanism of CuNPs detection of H 2 O 2 and glucose. [Display omitted] • Green precursor and ecofriendly route were applied for the synthesis of Blue fluorescent CuNPs. • CuNPs fluorescence probe had good water solubility and fluorescence properties. • CuNPs@Fe2+ fluorescence sensing system can be utilized for glucose detection using Fenton and enzymatic reaction.. • The CuNPs@Fe2+ fluorescence sensing system has good utility in the practical detection of hydrogen peroxide and glucose. Fluorescent copper nanoparticles (CuNPs) was synthesized by one-step chemical reduction method using ascorbic acid (AA) and copper sulfate (CuSO 4 ⋅5H 2 O) as raw materials, which had good water solubility and fluorescence properties. A green, simple and safe CuNPs@Fe2+ fluorescence probe was developed for the detection of hydrogen peroxide and glucose using Fe2+ as a bridge. The prepared CuNPs could obtain the maximum fluorescence emission wavelength at 440 nm when the excitation wavelength was 360 nm. The average particle size of CuNPs was 10 nm, which had good photobleach resistance, stability and salt tolerance. The fluorescence intensity was quenched due to electron transfer (ET) process when hydrogen peroxide was added to CuNPs@Fe2+ system. This result was mainly because Fenton reaction occured between hydrogen peroxide and Fe2+, producing hydroxyl free radicals (OH) and Fe3+. Since glucose could be catalyzed by specific glucose oxidase (GOX) to produce H 2 O 2 and corresponding oxidation products, the quantitative analysis of glucose was realized when glucose oxidase was introduced into the CuNPs@Fe2+ sensor system. Therefore, a novel CuNPs@Fe2+ fluorescent probe sensor study was constructed to further achieve quantitative detection of H 2 O 2 and glucose. Under the optimized experimental conditions, the linear ranges for H 2 O 2 and glucose were 28.219–171.562 μM and 1.237–75.771 μM, respectively. And the detection limits for H 2 O 2 and glucose were 7.169 μM and 0.540 μM, respectively. In addition, the mechanism of fluorescence probe quenching caused by the interaction between H 2 O 2 and CuNPs@Fe2+ was also discussed. The proposed sensing system had been applied successfully to the detection of glucose in human serum samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • Reconstructed Cu/Cu 2 O(X) (X = I, Br, and Cl) catalysts were prepared for CO 2 RR. • Cu/Cu 2 O(I) shows good catalytic performance with a FE of 58% for C 2+. • Reconstructed Cu+ and Cu0 species are primarily responsible for the activity. It is particularly desirable for the development of carbon utilization technologies to synthesize multicarbon products (C 2+) from the electrochemical CO 2 reduction reaction (CO 2 RR). In this work, Cu/Cu 2 O(X) catalysts (where X = I, Br, Cl) for selective electroreduction of CO 2 to C 2+ were reconstructed via cyclic voltammetry on carbon paper. The Faradaic efficiency (FE) for C 2+ (C 2 H 4 , C 2 H 5 OH, C 3 H 8 OH) production over Cu/Cu 2 O(Cl), Cu/Cu 2 O(Br) and Cu/Cu 2 O(I) reached 31%, 34% and 58%, respectively, at a potential of −0.76 V vs. the reversible hydrogen electrode (RHE). The Cu+ and Cu0 species obtained from the reconstruction of Cu/CuX are primarily responsible for the high C 2+ producing activity. [ABSTRACT FROM AUTHOR]

• MOFs-derived N-MHCNT/Cu x Co y -Fe@C prepared by a facile method. • N-doping, core-shell structure and alloys generated simultaneously. • Synergistic effects of HCNT, Cu x Co y -Fe alloy and core-shell structure. • Efficient catalytic performance and excellent durability for ORR. Carbon-based materials with transition metal modifications are the dominant materials for oxygen reduction reaction (ORR), but the synthesis in a simple and efficient way is still a great challenge. Herein, multicore-shell structure Cu x Co y -Fe alloy nitrogen doped mesoporous hollow carbon nanotubes (N-MHCNT/Cu x Co y -Fe@C) were designed and synthesized by a facile and environment-friendly method. In the process of pyrolysis, polypyrrole serving as the substrate to form N-doped hollow carbon nanotubes and the polydopamine (PDA) acts as the carbon and nitrogen source to form a shell structure. Additionally, the cubic Cu x Co y -Fe MOFs synthesized at room temperature collapses to form multiple alloy cores. Notably, the mesoporous structure of N-MHCNT/Cu x Co y -Fe@C enhances the mass transfer process, while the carbon shell protects the metal active sites. Moreover, mesoporous hollow carbon, rich M-N x (M=Cu, Co, Fe) active sites, the synergistic effects between N-MHCNTs, Cu x Co y -Fe alloys and multiple core-shell structures allowed N-MHCNT/Cu 2 Co 1 -Fe@C exhibited high activity and long-term durability in ORR. Besides, the RRDE tests confirms the reaction kinetics of N-MHCNT/Cu 2 Co 1 -Fe@C as a mainly 4-electron reaction with an electron transfer number of 3.78 (Pt/C is 3.86) and a low hydrogen peroxide yield of 16%. This work provides a new strategy for the development of non-precious metal ORR catalysts by rational structural design and metal ratio adjustment. Multicore-shell structure Cu x Co y -Fe alloy nitrogen doped mesoporous hollow carbon nanotubes composites for oxygen reduction reaction [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The Yangla copper deposit is a recently discovered, giant copper deposit with an estimated Cu reserve of about 1,200,000tons. Development is now underway. Previous studies have reported that the Yangla copper deposit is a VMS-type deposit related to the Yangla volcanic rocks. Volcanic bulk-rock analyses shows high contents of Si (49.3%–58.7%), Na2O (Na2O=3.3%–4.9%), MgO (MgO=3.7%–8.6%), and CaO(CaO=6.8%–9.0%), low TiO2 (TiO2 =0.9%–2.1%) and K2O(K2O=0.2%–1.4%) contents. The geochemistry of the volcanic represent forearc basalts. Four molybdenites samples from the ore bodies in the deposit yield Re–Os model ages ranging from 229.7±3.3Ma to 233±3.4Ma. The REE distribution patterns and the primitive-mantle-normalized trace element patterns of the volcanic rocks are similar to the ores, indicating the Yangla copper deposit are closely associated with the Yangla volcanic rocks. The results contribute to our understanding of the genesis of the Yangla copper deposit and will guide further exploration in the region. [Copyright &y& Elsevier]

Abstract: In this paper, a high damping Mg–1%Mn based alloy with good corrosion resistance and adequate strength was prepared by studying the properties of Mg–Mn alloys. The effects of Cu addition on microstructure, mechanical properties and damping capacity of Mg–1%Mn alloy were investigated. The results show that Cu addition remarkably reduces the grain size of Mg–1%Mn alloy and a new binary phase, Mg2Cu, can be identified, which segregates at grain boundaries in the form of divorced eutectic and worsens the tensile properties. Using a low strain amplitude, the damping capacities of Mg–Cu–Mn alloys show minor variation with increasing Cu content, while with a high strain amplitude, the internal friction decreases with the smaller grain size and increasing amount of precipitates. In addition, the temperature dependent damping behavior of the Mg–Cu–Mn alloys was also discussed. [Copyright &y& Elsevier]

The two important transparent p-type conducting title oxides are prepared by a one-step low temperature hydrothermal method in an autoclave. [ABSTRACT FROM AUTHOR]