Science Daily February 16, 2023 In this study, a novel and economical green sustained-release microcapsule salt-storage anti-icing agent was prepared by researchers in China using solid waste porous sustained-release skeleton loading organic acetate salt as the core material and styrene-acrylic-acrylate copolymer P(AA-MA-BA-St) as the wall material, which have less corrosiveness and extended the release time. The blast furnace slag and NaHCO3 were selected as the sustained-release skeleton and corrosion inhibitors. The optimal conditions of the synthesis of vesicle wall materials were investigated: 3.8 wt % acrylic acid polymerized at 110 °C with 3 wt % AIBN and for 3.5 h, […]
Tag Archives: S&T China
Scientists realize faster method for quantum key distribution
Phys.org February 8, 2023 In the past two decades, quantum key distribution networks based on telecom fibers have been implemented on metropolitan and intercity scales. One of the bottlenecks lies in the exponential decay of the key rate with respect to the transmission distance. Recently proposed schemes mainly focus on achieving longer distances by creating a long-arm single-photon interferometer over two communication parties. Despite their advantageous performance over long communication distances, the requirement of phase locking between two remote lasers is technically challenging. By adopting the recently proposed mode-pairing idea, researchers in China have demonstrated high-performance quantum key distribution without […]
Toward practical quantum optics: Multiphoton qubits from LNOI
Phys.org February 8, 2023 The large-photon-number quantum state is a fundamental but nonresolved request for practical quantum information applications. Researchers in China have proposed a N-photon state generation scheme that is feasible and scalable using lithium niobate on insulator circuits. The scheme was based on the integration of a common building block photon-number doubling unit (PDU) for deterministic single-photon parametric downconversion and upconversion. The PDU relies on a 107-optical-quality-factor resonator and mW-level on-chip power, which is within the current fabrication and experimental limits. N-photon state generation schemes, with cluster and Greenberger–Horne–Zeilinger state as examples, are shown for different quantum tasks… read more. […]
Team develops strategy to regulate light absorption behaviors of titanium oxo clusters
Phys.org January 23, 2023 Researchers in China constructed two heterometallic clusters to improve the solar absorption and performance of titanium oxo clusters. Their studies indicated that these structures exhibited enhanced visible-light absorption and significantly reduced optical band gaps which could be mainly attributed to the introduction of electron-rich molybdenum (Mo) pairs as heterometals. They found that the electron-rich Mo–Mo pairs could be introduced to titanium oxo clusters to enhance visible-light absorption. They attributed the reduction in the band gaps to the introduction of electron-rich Mo-Mo pairs as heterometals. They also found that the bands shift effectively toward the visible-light region. […]
Researchers create an optical tractor beam that pulls macroscopic objects
Science Daily January 11, 2023 In recent ten years, optical pulling of micro-nano objects have been fully demonstrated. However, optical pulling of a macroscopic object is challenging. Researchers in China have demonstrated laser pulling of a macroscopic object in rarefied gas. The pulling force was originated from the Kundsen force when a gauss laser beam irradiates a macroscopic structure composed of the absorptive bulk cross-linked graphene material and a SiO2 layer. A torsional pendulum device qualitatively presented the laser pulling phenomenon. A gravity pendulum device was used to further measure the pulling force that is more than three orders of […]
New strategy proposed for ultra-long cycle lithium-ion battery
Phys.org December 15, 2022 In the process of battery reaction, stress accumulation and lattice oxygen loss will cause some microcracks in lithium-rich manganese-based materials. The migration of transition metal ions will lead to phase transition of materials and other harmful side reactions. Researchers in China prepared high-performance cathode materials for lithium-rich manganese-based lithium-ion batteries. They did sulfur doping and in-situ growth of coherent spinel phase synchronously on the surface of lithium-rich manganese-based materials. The formation of TM-S bond configuration induced by S incorporation can effectively accelerated the lithium ions diffusion and suppressed the undesired oxygen redox. Therefore, the LMRS@S cathode […]
Unique modulator could change mid-infrared photonic systems for the better
Phys.org December 12, 2022 Optical modulators are crucial photonic circuits that enable signal switching and routing, data encoding, phase-sensitive detection, and spectroscopic interrogation. Researchers in China have developed a new MIR all-optical modulator based on an acetylene-filled hollow-core fiber. Optical absorption of the control beam promotes the gas molecules to a higher energy level, which induces localized heating through non-radiative relaxation and modulates the refractive index of the gas material and hence the accumulated phase of the signal beam propagating through the hollow-core fiber. By modulating the intensity of the control beam, they modulated the phase of the signal beam. […]
On-demand storage of photonic qubits at telecom wavelengths
Phys.org December 6, 2022 Researchers in China processed a fiber-integrated quantum memory at telecom wavelengths based on a laser-written waveguide fabricated in an erbium-doped yttrium silicate. Both ends of the waveguide memory were directly connected with fiber arrays with a fiber-to-fiber efficiency of 51%. Storage fidelity of 98.3(1)% was obtained for time-bin qubits encoded with single-photon-level coherent pulses, which is far beyond the maximal fidelity that can be achieved with a classical measure and prepared strategy. This device featured high reliability and easy scalability, and it can be directly integrated into fiber networks, which could play an essential role in […]
Flexible strain sensor enabled by carbon nanofibers can ‘read lips’
Phys.org November 29, 2022 While high sensitivity and wide working range are desired key parameters for a strain sensor, they are usually contrary to each other to be achieved on the same sensor due to the tight structure dependence of both. Researchers in China used an integrated membrane containing both parallel aligned and randomly aligned carbon nanofibers (CNFs) to design a flexible strain sensor with high sensitivity and wide strain detection range. The parallel aligned CNF membrane (p-CNF) exhibited a low strain detection limit and high sensitivity, while the random aligned CNF membrane (r-CNF) exhibits a large strain detection range. […]
Researchers develop highly CO-tolerant fuel cell anode catalyst
Phys.org November 29, 2022 Platinum on carbon (Pt/C) catalyst is commercially adopted in fuel cells but it undergoes active-site poisoning by carbon monoxide (CO) diminishing the device performances. Researchers in China incorporated cobalt (Co) into molybdenum-nickel alloy (MoNi4), termed Co-MoNi4, which not only shows superior hydrogen oxidation reaction activity over the Pt/C catalyst in alkali, but exhibits excellent CO tolerance with only small activity decay after 10 000 cycles. It yielded peak power density far exceeding the Pt/C catalyst. Experimental and computational studies revealed that weakened CO chemisorption originates from the electron-deficient Ni sites… read more. TECHNICAL ARTICLE