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Cu/SAPO-34 is a highly efficient catalyst that can be used in various catalytic fields. However, the use of phosphoric acid during the preparation process exacerbates environmental pollution issues. This article uses aluminum phosphate as a new raw material and uses direct ion exchange to effectively control and reduce pollution in the process of preparing Cu/SAPO-34. A series of physical and chemical properties and catalytic performance of the catalyst were analyzed and studied using various characterization instruments. The results indicate that the Cu/SAPO-34 catalyst has more isolated Cu2+ and Cu[OH]+ sites than the Con-Cu/SAPO-34 catalyst prepared by traditional methods, and exhibits excellent ability to remove NOx in the temperature range of 100–550 °C. [ABSTRACT FROM AUTHOR]

Recent progress in studying copper‐dependent targets and pathways in the context of tumor treatment has provided new insights into therapeutic strategies of leveraging copper‐dependent disease vulnerabilities and pharmacological manipulation of intratumor copper transportation to improve chemotherapy. Here, we developed reactive oxygen species (ROS)‐sensitive nanoparticles loaded with copper chaperone inhibitor DC_AC50 and cisplatin(IV) prodrug. The released DC_AC50 can promote a remarkable accumulation of intracellular cisplatin and copper through inhibition of the Atox1‐ATPase pathways, thereby enhancing the chemotherapeutic effect of cisplatin and inducing significant ROS generation. Excessive ROS then elicits intense endoplasmic reticulin (ER) stress which facilitates the immunogenic cell death (ICD) spurring a sustained immune response. Our study suggests that nanoparticle‐mediated copper chaperone inhibition via DC_AC50 can restore the immunogenicity of tumor cells for enhanced chemotherapy and cancer immunotherapy. [ABSTRACT FROM AUTHOR]

Surface texture is a valid way of improving hydrodynamic lubrication performance and reducing friction. In this work, a novel micro-additive manufacturing technique, selective laser melting ink-printed (SLM-IP) copper (Cu) nanoparticles (NPs) method, was developed to fabricate Cu protruded microtextures on stainless steel surface. The physical effects of texture geometry parameters on the hydrodynamic lubrication performance were investigated by theoretical calculation and experiments. The theoretical results indicated that the triangle-shaped microtexture exhibited better hydrodynamic effects compared to circular and square-shaped ones. The use of a complicated ring structure resulted in a noticeable increase in hydrodynamic pressure. For each individual shape, the friction coefficient was measured and calculated as a function of texture area or radius ratio. The experimental results, supported by the theoretical analysis, provides evidence that the protruded surface microtexture fabricated by SLM-IP Cu NPs helped improve the tribological performance. The geometric parameters of the protruded microtexture's size should be taken into account for the optimum size of texture structure. Furthermore, the operating condition of the protruded surface texture were evaluated. A transition point of sliding speed and load existed between mixed and hydrodynamic lubrication regimes. This study suggests that the SLM-IP Cu NPs method is a promising approach for friction reduction surface microtexture manufacturing. [ABSTRACT FROM AUTHOR]

Electrocatalytic CO 2 reduction reaction (CO 2 RR) over Cu-based electrocatalysts still suffered from low efficiency but high energy consumption. In this study, atomic-dispersed Sn-modified Cu nanowires (Cu@Sn NWs) were synthesized for selective electrocatalytic CO 2 RR to CO with an optimized FE CO of 96.4 %. Moreover, formaldehyde oxidation half-reaction (FOR) at MnO 2 /CP anode, replacing water oxidation (WOR), was introduced to build a novel CO 2 RR/FOR system with CO 2 RR over Cu@Sn NWs, to further improve CO 2 RR efficiency and to reduce the energy consumption. Generally, compared with CO 2 RR/WOR system, CO 2 RR/FOR system shows a much higher CO 2 RR performance. Meanwhile, HCHO can be converted to HCOOH at MnO 2 /CP anode with tunable selectivity (50 ∼ 65 %), depending on the applied cell voltage. Specifically, at a cell voltage of 3.5 V, about 97.9 % of HCHO can be removed with HCHO→HCOOH selectivity of about 50 %. Moreover, the working cell voltage and energy consumption can be significantly reduced over CO 2 RR/FOR system, versus CO 2 RR/WOR system. For example, at the current density of − 4 mA/cm2 (FE CO = ∼95 %), the cell voltage is lower by about 270 mV, and the energy consumption is lower by about 8.97 %. Compared with the sum of the energy consumption of a single CO 2 RR and FOR, the energy consumption of the CO 2 RR/FOR system can be reduced by about 47.3 %. When solar cells were used as the power supply, the CO generation rate in the CO 2 RR/FOR system is about 1.43 times that in the CO 2 RR/WOR system, accompanied by the anodic conversion of HCHO to HCOOH with the selectivity of 58.2 %. [Display omitted] • Cu@Sn NWs show excellent CO selectivity. • CO 2 RR/FOR system can selectively reduce CO 2 to CO and oxidize HCHO to HCOOH. • The CO 2 RR performance of CO 2 RR/FOR system is higher than that of CO 2 RR/WOR system. • The pairing of CO 2 RR and FOR can reduce the required energy. [ABSTRACT FROM AUTHOR]

A method of selective laser melting of ink-printed (SLM-IP) Cu nanoparticles (NPs) for facile controllable fabrication of super-hydrophobic surface structure is reported in this paper. A hierarchical structure composed of micro/nano-scaling copper (Cu) meshing texture was obtained by SLM-IP NPs. The meshing sizes are varied from 0.05 mm to 0.23 mm. By applying the analysis of SEM, XRD, Confocal Laser Scanning Microscope (CLSM), apparent contact angle (CA) measurement and water droplet dynamic behavior analysis, the effects of both mesh size and nano-sized structures on the hydrophobicity were discussed. The results show that the mesh surface fabricated by SLM-IP Cu NPs expresses an excellent super-hydrophobicity with a CA as high as 160° and sliding angle as low as 3.9° with a mesh grid size of 0.05 mm. An apparent CA model for double roughness structure was used to predict the CAs. The calculated CAs show a good agreement with the measurements when the mesh grid size is far less than the radius of water drop. SLM-IP Cu NPs takes the advantages of additive manufacturing and provides a flexible way for the functional surface structure fabrication. [ABSTRACT FROM AUTHOR]

In this paper, a nano-sized amorphous carbon covered surface was fabricated by an additive manufacturing process of selective laser melting of ink-printed (SLM-IP) copper (Cu) nanoparticles (NPs) in ambient condition. This technique synthesizes pure Cu by chemical reduction route using an organic solvent during laser melting. Additionally, the polymer in the solvent was decomposed by the thermal energy, which resulted in the formation of nano-sized amorphous carbon. Consequently, two layers of copper and carbon were fabricated on the substrate of stainless steel which was illustrated by the cross-section SEM. The upper layer of carbon possesses super-hydrophobic and high-light absorptance properties. The reaction products were characterized by the analyze of XRD, XPS and EDS. The contact angle and dynamic behavior of water droplet on the fabricated surface were carried out to demonstrate the super-hydrophobicity. The study provides an easy and flexible method for the fabrication of the functional surface by laser sintering in air ambient. [ABSTRACT FROM AUTHOR]

This paper reports a process of selective laser melting of ink-printed (SLM-IP) copper (Cu) nanoparticles(NPs) for the fabrication of full dense Cu friction-reducing texture on the metallic surface in ambient condition. This technique synthesizes pure Cu by chemical reduction route using an organic solvent during laser melting in the atmosphere environment, and provides a flexible additive manufacture approach to form complex friction-reduction texture on the metallic surface. Microtextures of ring and disc arrays have been fabricated on the stainless steel surface by SLM-IP Cu NPs. The friction coefficient has been measured under the lubricating condition of the oil. Disc texture surface (DTS) has a relatively low friction coefficient compared with ring texture surface (RTS), Cu film surface (Cu-FS) and the untreated substrate. The study suggests a further research on SLM-IP approach for complex microstructure or texture manufacturing, possibly realizing its advantage of flexibility. [ABSTRACT FROM AUTHOR]

Abstract: Cu6−x Ni x Sn5 is an important intermetallic compound (IMC), which was known to greatly improve the reliability of the solder joints in integrated circuits. However, the improvement mechanisms and even the crystal structure of the IMC were not fully understood. In this paper, the first-principles calculations were performed to determine the stable structure of Cu6−x Ni x Sn5 IMC. The structural and electronic properties of Cu6−x Ni x Sn5 (x =0, 1, 2) IMCs have been calculated. The results show that Ni atoms preferentially occupied 8f sites (Cu2) and formed Cu4Ni2Sn5. The results of energy calculation and density of states demonstrate that this Cu4Ni2Sn5 IMC had a more stable structure than Cu6Sn5. These results are also expected to account for the improvement in the reliability of the solder joint. [Copyright &y& Elsevier]

In this study, a monomer-induced self-assembly growth path was proposed for the controllable synthesis of core-shell heterostructured MOF(Fe/Cu) DT @COF hybrid nanomaterial (MOF, metal-organic framework; COF, covalent-organic framework; DT, 2,5-dimethoxyterephaldehyde), which exhibited highly ordered crystal structure and uniform distribution. Then, 2,4,6-trichlorophenol (TCP) was selected as the target molecule to construct the MOF(Fe/Cu) DT @COF electrochemical sensor for selective and sensitive detection. Relevant investigations indicate that the assembled columnar COF shell is availably able to promote the diffusion of TCP to the bimetallic active center of MOF, which exhibits excellent electrocatalytic performance via the synergistic effect. The two linear dynamic ranges of current response under the optimal conditions (pH = 8.0) are 0.01–10 and 10–900 μmol L-1, respectively, with a 0.003 μmol·L-1 (S/N = 3) detection limit. On this sensor platform, there was also negligible interference from other ions that were present, which allowed the sensor based on MOF(Fe/Cu) DT @COF to detect low abundance TCP from actual samples. The article will inspire engineers and scientists working in the field of MOFs/COFs, whose concerted efforts will lead to more novel nanomaterials and will speed up the development of electrochemical sensing based on heterostructured hybrids of MOFs and COFs. [Display omitted] • The core-shell structured MOF(Fe/Cu) DT @COF was successfully constructed. • The resultant material enhanced TCP electrochemical sensing performance. • The synergistic effect of bi-metallic MOF and COF was discussed in detail. • The sensor could detect TCP in real samples with satisfactory recoveries. [ABSTRACT FROM AUTHOR]

Abstract Surface texturing is an effective way for friction-reduction in hydrodynamic lubricating conditions. In this paper, an additive manufacturing method of selective laser melting of ink-printed copper nanoparticles (SLM-IP Cu NPs) was introduced. Concave squared textures, convex squared textures and fully sintered Cu film were fabricated. The tribological performances of the fabricated samples showed that the convex squared texture possesses a better friction-reducing ability than the concave textures and the full Cu film. Moreover, the relationship between the dimensional parameters of the convex textures and the friction-reducing ability was also experimentally studied. The lubricating condition was analyzed to show that the surface structures fabricated by SLM-IP Cu NPs can provide the surface with a friction-reducing ability in mixed lubrication. Highlights • Convex friction-reducing textures were fabricated by a 3-dimensional ink printing of SLM-IP Cu NPs. • The convex texture shows a better friction-reducing ability. • The dimensional characteristics of convex texture directly affect the friction-reduction performances. • The friction reduction of convex texture can be attributed to mixed lubrication under high load or low speed. [ABSTRACT FROM AUTHOR]

Cu-SAPO-34 catalyst with CHA topology is widely used in the elimination of nitrogen oxides in automobile exhaust because of its excellent catalytic performance. A new method of directly synthesizing Cu-SAPO-34 from a new raw material instead of the original phosphorus source (phosphoric acid) was proposed. The new raw material AlPO 4 can also act as an aluminum source in addition to serving as a phosphorus source. The two groups of samples took morpholine (MOR) and diethylamine (DEA) as templates respectively, and Cu-TEPA was used as Cu source to participate in the synthesis of the catalyst. The Cu-SAPO-34 catalysts had high NO conversion, and their activities were analyzed according to the characterization methods. The phase structure, active sites, strength of acid sites of Cu-SAPO-34 were analyzed by XRD, XPS, H 2 -TPR and NH 3 -TPD. In addition, the activity of directly synthesized Cu-SAPO-34 catalyst under different copper content and different template conditions was compared. The NO conversion of Cu 0.05 -SAPO-34-DT is 100% at 225–350 °C, while that of Cu 0.05 -SAPO-34-MT is more than 90% at 175–375 °C. As the raw material for direct synthesis of Cu-SAPO-34, AlPO 4 not only reduces the synthesis cost, but also is more environmentally friendly. [Display omitted] • Cu-SAPO-34 were successfully prepared with direct hydrothermal synthesis method by using different templates. • AlPO 4 replaced phosphoric acid as the solid phosphorus source of the Cu-SAPO-34 catalysts. • These Cu-SAPO-34 catalysts exhibited excellent NH 3 -SCR performance. [ABSTRACT FROM AUTHOR]