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The preparation of atom-thick porous lattice hosting Å-scale pores is attractive to achieve a large ion-ion selectivity in combination with a large ion flux. Graphene film is an ideal selective layer for this if high-precision pores can be incorporated, however, it is challenging to avoid larger non-selective pores at the tail-end of the pore size distribution which reduces ion-ion selectivity. Herein, we develop a strategy to overcome this challenge using an electrochemical repair strategy that successfully masks larger pores in large-area graphene. 10-nm-thick electropolymerized conjugated microporous polymer (CMP) layer is successfully deposited on graphene, thanks to a strong π-π interaction in these two materials. While the CMP layer itself is not selective, it effectively masks graphene pores, leading to a large Li+/Mg2+ selectivity from zero-dimensional pores reaching 300 with a high Li+ ion permeation rate surpassing the performance of reported materials for ion-ion separation. Overall, this scalable repair strategy enables the fabrication of monolayer graphene membranes with customizable pore sizes, limiting the contribution of nonselective pores, and offering graphene membranes a versatile platform for a broad spectrum of challenging separations. The preparation of atom-thick lattices with Å-scale pores is desirable for achieving ion selectivity and high ion flux. Here authors present a cm-scale membrane made of atom-thick graphene film hosting zero-dimensional pores spanning only a few Å, repaired using an in situ electrochemical strategy, yielding high Li+/Mg2+ separation performance. [ABSTRACT FROM AUTHOR]

Simple Summary: With the rapid development of aquaculture, searching for alternative lipid sources to fish oil has become an important task for the aqua-feed industry. Lard is regarded as a valuable alternative lipid source. Basa fish (Pangasius bocourti) offal oil also has a large annual production and high potential to be used in fish feeds. Evaluation of the efficacy of lard and Basa fish offal oil in fish feeds will provide useful information for their application in aquaculture. Both lard and Basa fish offal oil have high levels of saturated fatty acids and monounsaturated fatty acids. The "n-3 LC-PUFA sparing effects" of saturated fatty acids and monounsaturated fatty acids in fish feeds have been observed in many fish species. The present study was also aimed at validating the "n-3 LC-PUFA sparing effects" of saturated fatty acids and monounsaturated fatty acids in lard and Basa fish offal oil. Moreover, the effects of dietary lard and Basa fish offal oil on fish body composition and muscle quality were also evaluated. Lard (LD) and Basa fish offal oil (BFO) have similar fatty acid profiles, both containing high contents of saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA). The present study aimed to investigate the efficacy of partial or complete replacement of marine fish oil (MFO, herring oil) by LD or BFO in the diets of tiger puffer. The control diet contained 49.1% crude protein and 9.28% crude lipid content including 6% added MFO. In other diets, 1/3, 2/3, and 3/3 of the added MFO was replaced by LD or BFO, respectively. Each diet was fed to triplicate tanks of juvenile fish (initial body weight, 13.88 g). A 46-day feeding trial was conducted in a flow-through seawater system. Each diet was fed to triplicate 200-L rectangular polyethylene tanks, each of which was stocked with 30 fish. Fish were fed to satiation three times a day. The complete replacement of added MFO (replacing 65% of the total crude lipid) had no adverse effects on fish growth performance in terms of survival (>94%), weight gain (360–398%), feed intake (2.37–3.04%), feed conversion ratio (0.84–1.02), and somatic indices. The dietary LD or BFO supplementation also had marginal effects on fish body proximate composition, biochemical parameters, muscle texture, and water-holding ability, as well as the hepatic expression of lipid metabolism-related genes. Partial (2/3) replacement of added MFO by LD or BFO did not significantly reduce the muscle n-3 LC-PUFA content, indicating the n-3 LC-PUFA sparing effects of SFA and MUFA in LD and BFO. In general, dietary LD or BFO reduced the peroxidation level and led to significant changes in the muscle volatile flavor compound profile, which were probably attributed to the change in fatty acid composition. The results of this study evidenced that LD and BFO are good potential lipid sources for tiger puffer feeds. [ABSTRACT FROM AUTHOR]

Research on metal-organic frameworks (MOFs) based membranes has gained a lot of attention in the last decade thanks to the unique and highly versatile chemistry of MOFs, which allows one to synthesize a variety of structural dimensions, topologies, pore sizes, pore shapes, functional groups, and chemical environments. For membrane application, the field is rapidly progressing, with the focus shifting from the synthesis of pinhole-free polycrystalline films to the synthesis of ultrathin MOF films on scalable support to surpass the performance of polymeric membranes. In this research update, we review promising methodologies for the synthesis of ultrathin MOF membranes. We then discuss the application of these ultrathin MOF films in gas separation, ion transport and ion–ion separation, and desalination. We then provide our perspective on opportunities and challenges for the future development of ultrathin MOF membranes. [ABSTRACT FROM AUTHOR]

Fabricating ultrathin covalent organic framework (COF) membranes toward high‐permeance molecular separations is highly desired yet challenging. Herein, a polyelectrolyte‐mediated assembly (PMA) strategy is developed to fabricate ultrathin ionic COF membrane for efficient CO2 separation. The PMA strategy allows a facile control over the assembly mode between polyethyleneimine (PEI) and TpPa‐SO3H, yielding PEI‐bridged ultra‐large COF nanosheets which are readily processed into COF membranes with thickness down to 8 nm. The resulting COF membranes exhibit a high CO2 permeances of 1371 GPU and CO2/N2 selectivity of 33 for stimulated flue gas. This PMA strategy may open up a new avenue to fabricating ultrathin 2D material membranes for diverse applications. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are one of the most promising membrane materials for olefin/paraffin separations. However, most of MOF membranes have a thickness over 1 µm, which greatly compromises the permeation flux. While previous studies are focused on increasing crystal nucleus density on the substrates, achieving ultrathin membrane via modulation of the crystal growth is lacking. Herein, an inhibited Ostwald ripening (IOR) strategy is proposed to fabricate ultrathin ZIF‐8 membranes, through incorporating polymer‐based inhibitors into the membrane formula to inhibit the growth process of ZIF‐8 crystals via the metal–organic coordination. The IOR process can be readily tuned by varying the functional groups, molecular weights, and concentrations of the inhibitors, enabling a facile control over the IOR degree and thus the membrane thickness. Consequently, the thickness of ZIF‐8 membranes can be dramatically reduced to 180 nm. The resulting membranes exhibit ultrahigh C3H6/C3H8 separation performance with C3H6 permeance of 386 GPU and C3H6/C3H8 separation factor of 120. It is anticipated that this straightforward and efficient IOR strategy can open a new avenue for the fabrication of ultrathin MOF membranes to tackle many critical molecular separations. [ABSTRACT FROM AUTHOR]

Covalent organic framework (COF) membranes with tunable ordered channels and free organic groups hold great promise in molecular separations owing to the synergy of physical and chemical microenvironments. Herein, we develop a defect engineering strategy to fabricate COF membranes for efficient CO2 separation. Abundant amino groups are in situ generated on the COF nanosheets arising from the missing‐linker defects during the reactive assembly of amine monomer and mixed aldehyde monomers. The COF nanosheets are assembled to fabricate COF membranes. Amino groups, as the CO2 facilitated transport carriers, along with ordered channels endow COF membrane with high CO2 permeances exceeding 300 GPU and excellent separation selectivity of 80 for CO2/N2, and 54 for CO2/CH4 mixed gas under humidified state. Our defect engineering strategy offers a facile approach to generating free organic functional groups in COF membranes and other organic framework membranes for diverse chemical separations. [ABSTRACT FROM AUTHOR]

Covalent organic framework (COF) membranes with tunable ordered channels and free organic groups hold great promise in molecular separations owing to the synergy of physical and chemical microenvironments. Herein, we develop a defect engineering strategy to fabricate COF membranes for efficient CO2 separation. Abundant amino groups are in situ generated on the COF nanosheets arising from the missing‐linker defects during the reactive assembly of amine monomer and mixed aldehyde monomers. The COF nanosheets are assembled to fabricate COF membranes. Amino groups, as the CO2 facilitated transport carriers, along with ordered channels endow COF membrane with high CO2 permeances exceeding 300 GPU and excellent separation selectivity of 80 for CO2/N2, and 54 for CO2/CH4 mixed gas under humidified state. Our defect engineering strategy offers a facile approach to generating free organic functional groups in COF membranes and other organic framework membranes for diverse chemical separations. [ABSTRACT FROM AUTHOR]

In superconducting quantum circuits, airbridges are critical for eliminating parasitic slotline modes of coplanar waveguide circuits and reducing crosstalks between direct current magnetic flux biases. Here, we present a technique for fabricating superconducting airbridges. With this technique, a single layer of photoresist is employed, and the gradient exposure process is used to define the profile of airbridges. In order to properly obtain the bridge profile, we design exposure dosage based on residual photoresist thickness and laser power calibrations. Compared with other airbridge fabrication techniques, the gradient exposure fabrication technique provides the ability to produce lossless superconducting airbridges with flexible size and, thus, is more suitable for large-scale superconducting quantum circuits. Furthermore, this method reduces the complexity of the fabrication process and provides a high fabrication yield. [ABSTRACT FROM AUTHOR]

Ionic covalent organic framework nanosheets (iCOFNs) with long‐range ordered and mono‐dispersed ionic groups hold great potential in many advanced applications. Considering the inherent drawbacks of oil–water biphase method, herein, we explore an oil–water–oil triphase method based on phase engineering strategy for the bottom‐up synthesis of iCOFNs. The middle water phase serves as a confined reaction region, and the two oil phases are reservoirs for storing and supplying monomers to the water phase. A large aqueous space and low monomer concentration lead to the anisotropic gradual growth of iCOFNs into few‐layer thickness, large lateral size, and high crystallinity. Notably, the resulting three cationic and anionic iCOFNs exhibit ultra‐high aspect ratios of up to 20,000. We further demonstrate their application potential by processing into ultrathin defect‐free COF membranes for efficient biogas separation. Our triphase method may offer an alternative platform technology for the synthesis and innovative applications of iCOFNs. [ABSTRACT FROM AUTHOR]

Ionic covalent organic framework nanosheets (iCOFNs) with long‐range ordered and mono‐dispersed ionic groups hold great potential in many advanced applications. Considering the inherent drawbacks of oil–water biphase method, herein, we explore an oil–water–oil triphase method based on phase engineering strategy for the bottom‐up synthesis of iCOFNs. The middle water phase serves as a confined reaction region, and the two oil phases are reservoirs for storing and supplying monomers to the water phase. A large aqueous space and low monomer concentration lead to the anisotropic gradual growth of iCOFNs into few‐layer thickness, large lateral size, and high crystallinity. Notably, the resulting three cationic and anionic iCOFNs exhibit ultra‐high aspect ratios of up to 20,000. We further demonstrate their application potential by processing into ultrathin defect‐free COF membranes for efficient biogas separation. Our triphase method may offer an alternative platform technology for the synthesis and innovative applications of iCOFNs. [ABSTRACT FROM AUTHOR]

Invariant‐based shortcuts to adiabaticity (IB‐STA) approach is demonstrated to speed up the coherent population transfer of a three‐level quantum system on a superconducting circuit. Compared with the conventional stimulated Raman adiabatic passage (STIRAP), the scheme can achieve the same high transfer efficiency with evolution time reduced by 5.96 times. The final transfer efficiency of the scheme is measured to be 98.2±2.2%, which is mainly decoherence limited. Further, the robustness of the scheme is experimentally characterized, which is superior to the time‐optimal resonant Rabi scheme under systematic pulse amplitude error. Therefore, the approach provides an alternative approach to realize high‐fidelity state manipulation and preparation for weakly coupled Λ‐ or Ξ‐type quantum systems. [ABSTRACT FROM AUTHOR]

Possessing the noise-resilience feature, geometric phases have become important in robust quantum computation. Gates based on the Abelian and non-Abelian geometric phases have been experimentally demonstrated in different physical systems. However, previous proposals require cyclic evolution with a constant operation time even for small rotation angles, which set a limit to the gate operation time. Here, we experimentally realize noncyclic geometric gates, where the cyclic condition is removed and the operation time is proportional to the rotation angle. With the adiabatic process sped up by shortcut to adiabaticity, the fidelities of a noncyclic geometric gate characterized by randomized benchmarking are above 99.5%. Comparing with the dynamic scheme, we demonstrate the robustness of our gate against control instability in the experiment. Moreover, our results indicate that the noncyclic geometric gate with a smaller rotation angle corresponds to a shorter evolution time and higher fidelity. As small rotation angles are essential in the quantum algorithm, the superiority of noncyclic geometric gates makes them promising candidates in fast and robust quantum computation. [ABSTRACT FROM AUTHOR]

We demonstrate an active reset protocol in a superconducting quantum circuit. The thermal population on the excited state of a transmon qubit is reduced through driving the transitions between the qubit and an ancillary qubit. Furthermore, we investigate the efficiency of this approach at different temperatures. The result shows that population in the first excited state can be dropped from 7% to 2.55% in 27 ns at 30 mK. The efficiency improves as the temperature increases. Compared to other schemes, our proposal alleviates the requirements for measurement procedure and equipment. With the increase of qubit integration, the fast reset technique holds the promise of improving the fidelity of quantum control. [ABSTRACT FROM AUTHOR]

In superconducting quantum circuits, Josephson junctions are a key component to provide nonlinearity and enable superconducting qubits. Fabricating junctions with precise critical currents is crucial to defining qubit frequency. Here we suppress the critical current variation of Josephson junctions by varying the critical current density Jc and junction areas. The relative standard deviation of the critical current Ic is controlled to be below 0.8%. This uniform fabrication is promising for realizing scalable superconducting quantum computation. [ABSTRACT FROM AUTHOR]

Shortcuts to adiabaticity have been proved an effective routine for precise quantum state manipulation. Here, we experimentally demonstrate invariant-based shortcuts to adiabaticity to speed up the population transfer in a superconducting circuit. Through inverse engineering of the Hamiltonian, we realize this protocol in a single-qubit and a two-qubit system. The Lewis–Risenfeld phase is characterized experimentally. Furthermore, we investigate the robustness of the scheme against amplitude and frequency errors. [ABSTRACT FROM AUTHOR]

Coherent quantum state transfer is a vital step in quantum information processing. Based on the stimulated Raman adiabatic passage (STIRAP), we realize robust quantum state transfer between two superconducting qubits, mediated by a tunable coupler. Utilizing parametric coupling techniques, we construct the STIRAP Hamiltonian by modulating the coupler frequency. A population transfer fidelity of 95.1 (± 2.0) % is achieved and is consistent with the numerical simulation result of 95.4%. By preparing the initial state in the maximal superposition state of one qubit, we research how the phase of the transferred state is related to the modulation pulses. We also find that the transfer process is robust against the fluctuation of modulation frequency. Numerical simulation confirms that our state transfer scheme is more robust than non-adiabatic protocols. [ABSTRACT FROM AUTHOR]

We propose and demonstrate experimentally the arbitrary state-transfer in a qubit by using a superadiabatic approach in a superconducting circuit. We encode the qubit in a time-dependent dark state generated by an applied microwave field, speeding up the adiabatic evolution by transitionless quantum driving algorithms. This approach is realized experimentally in a qutrit system, which consists of a qubit and an ancillary level. Furthermore, we analyze the robustness of the implementation and measure the fidelity of transfer operation by using randomized benchmarking technique. [ABSTRACT FROM AUTHOR]

The thermal decomposition reactions of the complexes cis/trans-[Cu(gly)2] • H2O were studied by TG-DSC methods. The results showed that they have similar decomposition process, which occur in two steps. The first step is the loss of water and the second step is the decomposition of anhydrous complexes. But for cis-[Cu(gly)2]•H2O, the temperature of losing water is higher than that of trans-isomer. Their reaction mechanisms of the two-step decomposition were also proposed. [ABSTRACT FROM AUTHOR]

In quantum information processing, it is necessary to transfer quantum state between different systems. Herein, a scheme to transfer quantum state using multi‐passage Landau–Zener–Stückelberg interferometry in three superconducting qubits is proposed. A periodic triangle waveform quickly drives the system across the energy level anticrossing multiple times, inducing multiphoton Rabi oscillations. Using the 0‐photon Rabi oscillations, the dynamical quantum state transfer with probability close to 100% is realized. The fidelity of the state transfer is insensitive to local distortion of the driving waveform. This scheme can be extended to a system where multiple qubits are coupled to a frequency‐tunable qubit, as a quantum medium. It provides a useful tool for scalable quantum computing. [ABSTRACT FROM AUTHOR]