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A 56-day feeding trial was conducted to evaluate the effect of different dietary protein sources on the growth performance, muscle flavor substances, and quality structure of Triploid Crucian Carp. Three isonitrogenous (32.00%), isolipidic (8.00%), and isoenergetic (18.00 MJ kg−1) practical diets were formulated. These diets consisted of fishmeal as the animal-derived protein source (AP), a combination of soybean meal and rapeseed meal as the plant-derived protein source (PP), and a mixture of fishmeal, soybean meal, and rapeseed meal as the mixed protein source (MP). Each diet was randomly assigned to triplicate tanks of fish and each tank was stocked with 25 fish (11.5 ± 0.4 g). The fish were fed until apparent satiation twice a day. The results showed a significant enhancement in the growth performance of Triploid Crucian Carp in the AP group compared with both the MP and PP groups (p < 0.05). Dietary plant derived protein can remarkably reduce the crude lipid content and increase the moisture content of the whole body and the dorsal muscle (p < 0.05). The antioxidant ability of fish in the PP group and MP group was better than that in the AP group (p < 0.05). Regarding free amino acids composition of muscle, the contents of glycine, methionine, and lysine were significantly enhanced in the AP group, while the histidine content was significantly increased in the PP group (p < 0.05). In terms of texture, dietary plant protein significantly improved the muscular hardness, gumminess, and chewiness. The activities of intestinal trypsin and alkaline phosphatase (ALP) of fish in the PP group were significantly higher than that in the AP group (p < 0.05). The expression levels of hepatopancreas TOR and IGF1 genes in the PP group were significantly higher than that in the MP group (p < 0.05). The present results indicate dietary fishmeal significantly improved the growth performance and muscular flavor glycine content, while dietary plant-based protein increased crude protein content, antioxidant ability, and muscular texture performance of Triploid Crucian Carp. [ABSTRACT FROM AUTHOR]

One-dimensional RhCo alloy nanowires (NWs) with an ultrathin thickness (2.6 nm) and abundant defect sites were prepared in an aqueous solution by a nanoconfined attachment growth route within assembled columnar micelles. Thanks to dual synergies between advantageous anisotropic ultrathin structures and alloy compositions, they endowed one-dimensional RhCo NWs with superior activity and high stability for alkaline hydrogen evolution electrocatalysis. [ABSTRACT FROM AUTHOR]

In this paper, we report the use of additive manufacturing methods to fabricate a high aspect ratio, low noise amplifier (LNA) for a handheld active sensor device operating at up to 1 GHz. The new form factor LNA incorporates a modification of a square-shaped commercial off-the-shelf (COTS) LNA into a 5:1 aspect ratio device without a loss in RF performance. For rapid prototyping, we employ both subtractive and additive manufacturing technologies, such as milling, extrusion-based syringe printing, and aerosol jet printing techniques to fabricate both small form factor and high aspect ratio devices. The 5:1 aspect ratio LNA demonstrated a 20% smaller form factor, a gain of 25 dB, and an NF less than 3 dB over an operating frequency range up to 1 GHz, comparable to the COTS LNA. Design, simulation, and experimental results are given to highlight the advantages of 3D printed hybrid electronic technology over the conventional PCB fabrication method for rapid prototyping of RF electronic devices. [ABSTRACT FROM AUTHOR]

Patchy nanoparticles (NPs) show many important applications, especially for constructing structurally complex colloidal materials, but existing synthetic strategies generate patchy NPs with limited types of symmetry. This article describes a versatile copolymer ligand‐based strategy for the scalable synthesis of uniform Au‐(SiO2)x patchy NPs (x is the patch number and 1 ≤ x ≤ 5) with unusual symmetry at high yield. The hydrolysis and condensation of tetraethyl orthosilicate on block‐random copolymer ligands induces the segregation of copolymers on gold NPs (AuNPs) and hence governs the structure and distribution of silica patches formed on the AuNPs. The resulting patchy NPs possess unique configurations where the silica patches are symmetrically arranged at one side of the core NP, resembling the geometry of polar small molecules. The number, size, and morphology of silica patches, as well as the spacing between the patches and the AuNP can be precisely tuned by tailoring copolymer architectures, grafting density of copolymers, and the size of AuNPs. Furthermore, it is demonstrated that the Au‐(SiO2)x patchy NPs can assemble into more complex superstructures through directional interaction between the exposed Au surfaces. This work offers new opportunities of designing next‐generation complex patchy NPs for applications in such as biomedicines, self‐assembly, and catalysis. [ABSTRACT FROM AUTHOR]

Polymer‐grafted hairy nanoparticles (HNPs) that combine the unique properties of inorganic nanoparticles (NPs) and polymers are attractive building blocks for the layer‐by‐layer assembly of functional hybrid materials, but the adsorption behaviors of HNPs on substrates remain unclear. This article describes a systematic study on the adsorption behaviors of charged polymer‐grafted HNPs on oppositely charged substrates in different solvent media via a combination of experiments and simulations. It is shown in simulations that the adsorption process of HNPs is associated with the release of counterions around charged polymers on HNPs, thus resulting in a higher energy barrier of NP adsorption than bare NPs without charged polymer tethers. This energy barrier decreases with decreasing the dielectricity of solvents or ionization degree of grafted polymers or increasing ionic strength of the solution. Furthermore, the theoretical prediction is confirmed in experiments by using a model system of poly(acrylic acid)‐grafted silica NPs and poly(diallyldimethylammonium chloride)‐modified wafers. The work provides guidance for the electrostatic assembly of HNPs into functional hybrid composites with applications in membranes, optical devices, and biomedicines. [ABSTRACT FROM AUTHOR]

Ultrasmall silica‐based nanoparticles (SNPs) are attractive for application in many fields, but existing synthetic approaches show limited control over the size and morphology of these SNPs. This study describes a general single copolymer chain‐mediated strategy for the scalable synthesis of highly monodispersed symmetric and asymmetric SNPs with sub‐50 nm diameter. Random copolymers of poly(acrylic acid‐r‐styrene) intramolecularly collapse into ultrasmall single‐chain nanoparticles and serve as seeds to template the hydrolysis of silica precursors to produce uniform SNPs. It is shown in experiments and simulations that the composition and random architecture of the copolymers are crucial to the formation of ultrasmall seeds and the uniform deposition of silica. Furthermore, tailoring the architecture of copolymers can be used to produce ultrasmall asymmetric Janus‐like and dumbbell‐like SNPs with well‐defined polymer and silica domains. This study paves a new route to the scalable production of ultrasmall SNPs with tailored morphologies. [ABSTRACT FROM AUTHOR]

Nanoparticle clusters with molecular-like configurations are an emerging class of colloidal materials. Particles decorated with attractive surface patches acting as analogs of functional groups are used to assemble colloidal molecules (CMs); however, high-yield generation of patchy nanoparticles remains a challenge. We show that for nanoparticles capped with complementary reactive polymers, a stoichiometric reaction leads to reorganization of the uniform ligand shell and self-limiting nanoparticle bonding, whereas electrostatic repulsion between colloidal bonds governs CM symmetry. This mechanism enables high-yield CM generation and their programmable organization in hierarchical nanostructures. Our work bridges the gap between covalent bonding taking place at an atomic level and colloidal bonding occurring at the length scale two orders of magnitude larger and broadens the methods for nanomaterial fabrication. [ABSTRACT FROM AUTHOR]

The self-assembly of inorganic nanoparticles is of great importance in realizing their enormous potentials for broad applications due to the advanced collective properties of nanoparticle ensembles. Various molecular ligands (e.g., small molecules, DNAs, proteins, and polymers) have been used to assist the organization of inorganic nanoparticles into functional structures at different hierarchical levels. Among others, polymers are particularly attractive for use in nanoparticle assembly, because of the complex architectures and rich functionalities of assembled structures enabled by polymers. Polymer-guided assembly of nanoparticles has emerged as a powerful route to fabricate functional materials with desired mechanical, optical, electronic or magnetic properties for a broad range of applications such as sensing, nanomedicine, catalysis, energy storage/conversion, data storage, electronics and photonics. In this review article, we summarize recent advances in the polymer-guided self-assembly of inorganic nanoparticles in both bulk thin films and solution, with an emphasis on the role of polymers in the assembly process and functions of resulting nanostructures. Precise control over the location/arrangement, interparticle interaction, and packing of inorganic nanoparticles at various scales are highlighted. [ABSTRACT FROM AUTHOR]

Interfacial interactions between carbon nanotubes (CNTs) and metal matrices play a critical role in the bulk mechanical properties of CNT-reinforced metal matrix nanocomposites (MMNC), but their load-transfer mechanisms remain not well understood. In this paper, we conduct single-nanotube pull-out studies with in situ scanning electron microscopy to quantify the mechanical strength of binding interfaces in carbon nanotube (CNT)-reinforced titanium (Ti) nanocomposites. Our nanomechanical pull-out measurements reveal a shear lag effect in the load transfer on the CNT-Ti interface. The interfacial shear strength and the maximum load-bearing capacity of the tested CNT-Ti interfaces are quantified to be about 37.8 MPa and 245 nN, respectively, both of which are substantially higher than the reported values for CNT-Al interfaces. Density functional theory calculations reveal that the experimentally observed strong CNT-Ti binding interface is attributed to strong chemisorption interactions of Ti atoms on CNT surfaces, albeit moderated by the weakening effect of the oxide layer. The research findings are useful to better understand the load transfer process on the tube-metal interface and the reinforcing mechanism of nanotubes, and ultimately contribute to the optimal design and performance of nanotube-reinforced MMNC. [ABSTRACT FROM AUTHOR]

Interfacial load transfer plays a critical role in the bulk mechanical performance of nanofiber-reinforced metallic-matrix nanocomposites (MMNC). In this paper, we investigate the mechanical strength of interfaces in double-walled carbon nanotube (CNT)-reinforced aluminum (Al) nanocomposites by using in situ electron microscopy nanomechanical single-tube pull-out techniques. The nanomechanical measurements reveal the shear lag effect on the CNT-Al interface that is found to possess an average interfacial shear strength (IFSS) of about 28.7 MPa. The study also shows that thermal annealing results in substantially higher binding strength interfaces between CNTs and Al matrices. The average IFSS of CNT-Al interfaces that were thermally annealed at 400 °C is found to reach about 35.3 MPa, a 23% increase from that of the non-annealed interfaces. The maximum load bearing capacity of the annealed interfaces reaches about 304 nN, a 40.1% increase from that of the non-annealed ones (about 217 nN). The findings are useful to better understand the load transfer mechanism in CNT-reinforced MMNC and the tuning and optimization of the reinforcing performance through thermal processing. [ABSTRACT FROM AUTHOR]

In this study, a series of random copolymer poly(acrylic acid-co-styrene) (P(AA-co-St)) and block copolymer poly(acrylic acid)-b-polystyrene (PAA-b-PSt) with similar chemical composition but different chain microstructure were synthesized. The self-assembly behavior of random and block copolymers in selective solvent was investigated, and the structural evaluation of random and block copolymers micelles was carried out by transmission electron microscopy (TEM), dynamic light scattering (DLS) measurement, and X-ray photoelectron spectroscopy (XPS). Moreover, together with experimental characterization, the theoretical method dissipative particle dynamics (DPD) approach was applied to investigate the morphological structures of micelles composed from random and block copolymers. Results revealed that the structure of polymeric micelles is significantly affected by the distribution sequence of hydrophilic and hydrophobic monomers in copolymer chains. Furthermore, polymeric micelles based on P(AA-co-St) and PAA-b-PSt with about 50 mol% hydrophilic composition were chosen as the model to investigate the influence of micellar structure on emulsifying performance. For PAA-b-PSt micelles (B48), stable water-in-oil (w/o) emulsions could only obtained when the pH values were lower than 5. As a comparison, the P(AA-co-St) micelles (R49) had an excellent emulsification performance at 4–10 pH, and the pH-induced phase inversion derived from obtained emulsions observed at pH higher than 6. Preliminary results confirm that the micellar structure controlled by chain microstructure plays an important role in the interface behavior of polymer micelles. Compared with PAA-b-PSt micelles, P(AA-co-St) micelles have better interfacial performance and are more tailorable and controllable; thus they can be used as a model for further study of polymeric particulate emulsifiers. This paper provides new insight into the principles governing extremely high emulsifying efficiency of polymeric particulate emulsifiers and pH-responsive properties of the formed emulsions. [ABSTRACT FROM AUTHOR]

The stepwise self-assembly of hollow plasmonic vesicles with vesicular membranes containing strings of gold nanoparticles (NPs) is reported. The formation of chain vesicles can be controlled by tuning the density of the polymer ligands on the surface of the gold NPs. The strong absorption of the chain vesicles in the near-infrared (NIR) region leads to a much higher efficiency in photoacoustic (PA) imaging than for non-chain vesicles. The chain vesicles were further employed for the encapsulation of drugs and the NIR light triggered release of pay loads. This work not only offers a new platform for controlling the hierarchical self-assembly of NPs, but also demonstrates that the physical properties of the materials can be tailored by controlling the spatial arrangement of NPs within assemblies to achieve a better performance in biomedical applications. [ABSTRACT FROM AUTHOR]

A voltammetric paracetamol sensor based on molecularly imprinted polymeric (MIP) micelles was prepared by direct electrodeposition. The MIP micelles were prepared via macromolecule self-assembly of an amphiphilic photocrosslinkable copolymer using paracetamol as the template molecule. The resultant molecularly imprinted polymeric micelles swelled with increasing pH, and the disassociation of the micelles occurred at pH above approximately 7.4. A robust MIP film with good solvent resistance was formed on the electrode surface by anodic electrodeposition of the MIP micelles and subsequent photocrosslinking, resulting in the fabrication of a MIP electrochemical sensor for detecting paracetamol. The resultant sensor showed good response and selectivity towards paracetamol. In addition, a wide linear range from 0.01 mmol/L to 8 mmol/L and a low detection limit of 1×10−6 mol/L for paracetamol detection was demonstrated based on this sensor. The MIP sensor also showed good stability and reversibility which was applied to determine paracetamol commercial tablets. [ABSTRACT FROM AUTHOR]

The hierarchical assembly of multifunctional materials is challenging. In their Communication on page 15809 ff., Z. H. Nie, X. Y. Chen, and co‐workers report the stepwise assembly of block‐copolymer‐tethered gold nanoparticles into strings that subsequently fold into vesicles with chain‐like ordering of the nanoparticles in the membrane. The resulting vesicular assemblies can be used for photoacoustic imaging and drug delivery owing to their strong absorption in the near‐infrared region. [ABSTRACT FROM AUTHOR]

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High-performance electromagnetic microwave (EM) absorbers demand not only wide effective absorption bandwidth (EAB) and strong absorption capability, but also lightweight and small thickness. In this work, a new strategy was developed to simultaneously strengthen the lossy capacity and reduce the inclusion loading by designing the orientation of inclusions and constructing multilayered gradient structures. Accordingly, Ti 3 C 2 T x MXene fillers were aligned in the same chains by the electric field-assisted alignment technique, forming a parallel-plate structure, throughout epoxy matrix resulting in strong lossy capacity. The widest EAB of aligned 16 wt% MXene/epoxy composite reached 5.08 GHz with a thickness of 1.34 mm. By comparison, the random 16 wt% MXene/epoxy composite exhibited an EAB of only 0.96 GHz with a thickness of 1.96 mm. Further, the impedance matching was optimized by designing multilayered gradient structures based on aligned MXene/epoxy composites. The trilayered gradient structure with an equivalent filler content of 10.97 wt% illustrated the best EAB of 6.01 GHz at only 1.53 mm thickness. In addition, the synergistic effect of the multiple loss mechanisms was also discussed. Overall, the proposed method demonstrates the effectiveness of coupling the alignment of inclusions with gradient structural design to prepare lightweight, thin, and high-performance EM absorbing materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: A new coumarin based colorimetric nickel sensor 1 with high selectivity and sensitivity toward Ni2+ ion was reported. The absorption maximum of 1 shows a large red shift from 341nm to 540nm (Δ=200nm) in the presence of Ni2+ ion, and the resulted color change from colorless to pink upon addition of Ni2+ is very easily observed by the naked eye, while other metal ions, such as Zn2+, Cd2+, Cu2+, Fe3+, Ag+, Pb2+, alkali metal and alkaline earth metal cations do not induce such a change. By the “naked eye”, the detection limit of Ni2+ is as low as 0.5μM in solution, which is lower than the current American Environmental Protection Agency (EPA) standard for drinking water. As far as we are aware of, this is the first reported colorimetric chemosensor capable of detecting Ni2+ ion. [Copyright &y& Elsevier]