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While Ru-catalyzed hydrogenolysis holds significant promise in converting waste polyolefins into value-added alkane fuels, a major constraint is the high cost of noble metal catalysts. In this work, we propose, for the first time, that Co-based catalysts derived from CoAl-layered double hydroxide (LDH) are alternatives for efficient polyolefin hydrogenolysis. Leveraging the chemical flexibility of the LDH platform, we reveal that metallic Co species serve as highly efficient active sites for polyolefin hydrogenolysis. Furthermore, we introduced Ni into the Co framework to tackle the issue of restricted hydrogenation ability associated with contiguous Co–Co sites. In-situ analysis indicates that the integration of Ni induces electron transfer and facilitates hydrogen spillover. This dual effect synergistically enhances the hydrogenation/desorption of olefin intermediates, resulting in a significant reduction in the yield of low-value CH4from 27.1 to 12.6%. Through leveraging the unique properties of LDH, we have developed efficient and cost-effective catalysts for the sustainable recycling and valorization of waste polyolefin materials.

Confinement effects in highly porous nanostructures can effectively adjust the selectivity and kinetics of electrochemical reactions, which can boost the methanol oxidation reaction (MOR). In this work, carbonized ZIF-8-confined hollow PtCo nanospheres (PtCo@carbonized ZIF-8) were fabricated using a facile strategy. A monodisperse confined region was successfully prepared, and the dispersion of the PtCo nanoparticles (NPs) could be precisely regulated, allowing for the effective tuning of the confined region. Thus, the precise regulation of the catalytic reaction was achieved. Importantly, hollow PtCo NPs were prepared using a method based on the Kirkendall effect, and their forming mechanism was systematically investigated. Because of the confinement effects of carbonized zeolitic imidazolate framework-8 (ZIF-8), the crystal and electronic structures of the PtCo NPs were able to be effectively tuned. Our electrochemical results show that PtCo@carbonized ZIF-8 composites manifest a higher mass activity (1.4 A mgPt–1) and better stability compared to commercial Pt/C.

Penehyclidine hydrochloride (PHC) has been used for many years as an anticholinergic drug for the treatment of acute organophosphorus pesticide poisoning (AOPP). The purpose of this meta-analysis was to explore whether PHC has advantages over atropine in the use of anticholinergic drugs in AOPP.

High-voltage power supplies are pivotal in sectors such as agriculture, medicine, and environmental protection. However, conventional high-voltage sources are associated with environmental pollution, cumbersome size, high costs, and significant safety risks due to the accompanying high current. To address these challenges, we propose a high-voltage source that employs a direct-current triboelectric nanogenerator (DC-TENG). Based on contact electrification and electrostatic breakdown effects, the inherent electrostatic charges and minimal fixed capacitance enable the DC-TENG to generate ultra-high voltage with low current effortlessly. To fully harness the potential of this high-voltage technology, a theoretical model encompassing multiple discharge domains is developed and the three main constraints on open-circuit voltage are identified. Guided by the model, the optimized DC-TENG achieves a record output voltage of 10.85 kV through structural and material optimizations, effectively achieving water-oil separation and air purification within 2.5 and 3 minutes, respectively. This research not only fully exploits the high-voltage capabilities of DC-TENG but also offers an eco-friendly, portable, cost-effective, and safe alternative for supplying ultra-high voltage.

Schistosomiasis has been subjected to extensive control efforts in the People's Republic of China (China) which aims to eliminate the disease by 2030. We describe baseline results of a longitudinal cohort study undertaken in the Dongting and Poyang lakes areas of central China designed to determine the prevalence of Schistosoma japonicum in humans, animals (goats and bovines) and Oncomelania snails utilizing molecular diagnostics procedures. Data from the Chinese National Schistosomiasis Control Programme (CNSCP) were compared with the molecular results obtained. Sixteen villages from Hunan and Jiangxi provinces were surveyed; animals were only found in Hunan. The prevalence of schistosomiasis in humans was 1.8% in Jiangxi and 8.0% in Hunan determined by real-time polymerase chain reaction (PCR), while 18.3% of animals were positive by digital droplet PCR. The CNSCP data indicated that all villages harboured S. japonicum-infected individuals, detected serologically by indirect haemagglutination assay (IHA), but very few, if any, of these were subsequently positive by Kato-Katz (KK). Based on the outcome of the IHA and KK results, the CNSCP incorporates targeted human praziquantel chemotherapy but this approach can miss some infections as evidenced by the results reported here. Sensitive molecular diagnostics can play a key role in the elimination of schistosomiasis in China and inform control measures allowing for a more systematic approach to treatment. [ABSTRACT FROM AUTHOR]

Innovative sodium-ion capacitors were fabricated based on 3D framework carbon cathode and biomass-based carbon nanosheet anode. The all-carbon sodium-ion capacitors exhibited high energy-power densities and outstanding cycle stability.

The imbalance between the extensive production and recycling of plastics has resulted in severe environmental and resource issues. A promising solution to mitigate this issue involves using chemical recycling methods to convert plastic products into high-value aromatic chemicals. However, the complexity of reaction mechanisms and the diverse array of reaction systems in this field hinder the establishment of unified principles. Addressing this challenge, we provide a comprehensive review of the current state of preparing aromatic chemicals from plastic wastes. This review discusses the reaction pathways for polyolefin and polyester plastics in the production of aromatics and summarizes the catalysts’ design and reaction mechanisms. Finally, we offer insights into the future of this field, with particular focus on the catalyst design for C–H activation, anticoking, selectivity of aromatics, and cascade reaction. These novel plastic recycling strategies present new perspectives for the green and sustainable development of society and the environment.

Touch panels utilizing surface-capacitive mechanism are ubiquitous in our daily life. However, the need for an additional probe signal generator and receiver module to detect the resistance distribution and variation caused by finger touching adds complexity and energy consumption to the system. Herein, we propose a self-powered and high-precision tribo-touch-position sensor (TPS) that can operate without an external probe signal generator and receiver module. By detecting the contact electrification signal and extracting the signal ratio between the edges of a uniform resistance film, TPS exhibits precise touch position detection with minimal channels. The mechanism and feasibility of this sensor is systematically analyzed from theory and experiment. Moreover, the resistance range and parameters that affect the sensing performance are discussed in depth. Compared to traditional capacitive touch panels, TPS can function in high moisture conditions and is not limited to grounded objects. Finally, the designed TPS achieves spatial resolutions of 0.001 and 1 mm in touching space and size, and a prototype 2D touch panel is fabricated experimentally. The signals ratio of 2D touch panel changes more obviously in the middle than on the sides while the fingers touch various positions. This work provides an alternative platform for simple and diverse contact localization using triboelectric effect.

With lightweight, high energy conversion and low cost, the triboelectric nanogenerators (TENGs) have presented its tremendous potential as a portable sustainable power source to small-scale portable/wearable electronic device. However, the insufficient output power of TENG is a bottleneck for its practical applications. Here, we report an ultrahigh output power, a whirligig-inspired TENG (Wi-TENG) designed according to an antiqueue whirligig toy that is capable of converting low-frequency pulling motion into a high-frequency rotation. It shows that the rotor in the Wi-TENG achieves a maximum speed of 11,250 rpm. Ultrahigh charge transfer quantity of ~ 310 μC and output power of 40.18 mW are obtained by per pulling of Wi-TENG. Moreover, a maximum short-circuit current of 317 μA and a constant open-circuit voltage peak value of 153 V can be generated by the Wi-TENG, which can rapidly charge a commercial capacitance (100 μF) to ~14 V within 10 s. After power management, this Wi-TENG is successfully demonstrated as a portable sustainable power source for driving a commercial blood glucose meter or a temperature-humidity sensor. This study presents the potential of Wi-TENG as a reliable portable instant power supply for personal health monitoring devices.

Triboelectric nanogenerator (TENG) has the output characteristics of high voltage but low current/charge-transfer, making its low efficiency in powering most of electronics. To address this problem, power management circuits consisting of coupled inductors or transformers are usually employed. Here we report an inductor-free, auto-power-management design based on automatic switches between serial-connected and parallel-connected capacitors in a rationally designed manner, so that the output voltage can be lowered and the output charge is enhanced in proportion. In conjunction to theoretical analysis, a TENG along with proof-of-concept power-management units as automatically driven by the triggering motion for TENG is fabricated, which improves the rate for charging a supercapacitor by 5 times. Compared to previous work, this power-management design shows advantages of capability for harvesting low power/frequency scale energy, high scalability, and light weight, which paves a new approach for achieving high-efficient portable TENG-based self-powered system.

The drastic expansion of consumer electronics (like personal computers, touch pads, smart phones, etc.) creates many human–machine interfaces and multiple types of interactions between human and electronics. Considering the high frequency of such operations in our daily life, an extraordinary amount of biomechanical energy from typing or pressing buttons is available. In this study, we have demonstrated a highly flexible triboelectric nanogenerator (TENG) solely made from elastomeric materials as a cover on a conventional keyboard to harvest biomechanical energy from typing. A dual-mode working mechanism is established with a high transferred charge density of ∼140 μC/m2due to both structural and material innovations. We have also carried out fundamental investigations of its performance dependence on various structural factors for optimizing the electric output in practice. The fully packaged keyboard-shaped TENG is further integrated with a horn-like polypyrrole-based supercapacitor as a self-powered system. Typing in normal speed for 1 h, ∼8 × 10–4J electricity could be stored, which is capable of driving an electronic thermometer/hydrometer. Our keyboard cover also performs outstanding long-term stability, water resistance, as well as insensitivity to surface conditions, and the last feature makes it useful to research the typing behaviors of different people.

A soft, stretchable, and fully enclosed self-charging power system is developed by seamlessly combining a stretchable triboelectric nanogenerator with stretchable supercapacitors, which can be subject to and harvest energy from almost all kinds of large-degree deformation due to its fully soft structure. The power system is washable and waterproof owing to its fully enclosed structure and hydrophobic property of its exterior surface. The power system can be worn on the human body to effectively scavenge energy from various kinds of human motion, and it is demonstrated that the wearable power source is able to drive an electronic watch. This work provides a feasible approach to design stretchable, wearable power sources and electronics.

Ocean wave associated energy is huge, but it has little use toward world energy. Although such blue energy is capable of meeting all of our energy needs, there is no effective way to harvest it due to its low frequency and irregular amplitude, which may restrict the application of traditional power generators. In this work, we report a hybrid nanogenerator that consists of a spiral-interdigitated-electrode triboelectric nanogenerator (S-TENG) and a wrap-around electromagnetic generator (W-EMG) for harvesting ocean energy. In this design, the S-TENG can be fully isolated from the external environment through packaging and indirectly driven by the noncontact attractive forces between pairs of magnets, and W-EMG can be easily hybridized. Notably, the hybrid nanogenerator could generate electricity under either rotation mode or fluctuation mode to collect energy in ocean tide, current, and wave energy due to the unique structural design. In addition, the characteristics and advantages of outputs indicate that the S-TENG is irreplaceable for harvesting low rotation speeds (<100 rpm) or motion frequencies (<2 Hz) energy, which fits the frequency range for most of the water wave based blue energy, while W-EMG is able to produce larger output at high frequencies (>10 Hz). The complementary output can be maximized and hybridized for harvesting energy in a broad frequency range. Finally, a single hybrid nanogenerator unit was demonstrated to harvest blue energy as a practical power source to drive several LEDs under different simulated water wave conditions. We also proposed a blue energy harvesting system floating on the ocean surface that could simultaneously harvest wind, solar, and wave energy. The proposed hybrid nanogenerator renders an effective and sustainable progress in practical applications of the hybrid nanogenerator toward harvesting water wave energy offered by nature.

Kelvin probe force microscopy (KPFM), a characterization method that could image surface potentials of materials at the nanoscale, has extensive applications in characterizing the electric and electronic properties of metal, semiconductor, and insulator materials. However, it requires deep understanding of the physics of the measuring process and being able to rule out factors that may cause artifacts to obtain accurate results. In the most commonly used dual-pass KPFM, the probe works in tapping mode to obtain surface topography information in a first pass before lifting to a certain height to measure the surface potential. In this paper, we have demonstrated that the tapping-mode topography scan pass during the typical dual-pass KPFM measurement may trigger contact electrification between the probe and the sample, which leads to a charged sample surface and thus can introduce a significant error to the surface potential measurement. Contact electrification will happen when the probe enters into the repulsive force regime of a tip–sample interaction, and this can be detected by the phase shift of the probe vibration. In addition, the influences of scanning parameters, sample properties, and the probe’s attributes have also been examined, in which lower free cantilever vibration amplitude, larger adhesion between the probe tip and the sample, and lower cantilever spring constant of the probe are less likely to trigger contact electrification. Finally, we have put forward a guideline to rationally decouple contact electrification from the surface potential measurement. They are decreasing the free amplitude, increasing the set-point amplitude, and using probes with a lower spring constant.

Although a triboelectric nanogenerator (TENG) has been developed to be an efficient approach to harvest mechanical energy, its robustness and lifetime are still to be improved through an effective and widely applicable way. Here, we show a rational designing methodology for achieving a significant improvement of the long-term stability of TENGs through automatic transition between contact and noncontact working states. This is realized by structurally creating two opposite forces in the moving part of the TENG, in which the pulling-away force is controlled by external mechanical motions. In this way, TENGs can work in the noncontact state with minimum surface wear and also transit into contact state intermittently to maintain high triboelectric charge density. A wind-driven disk-based TENG and a rotary barrel-based TENG that can realize automatic state transition under different wind speeds and rotation speeds, respectively, have been demonstrated as two examples, in which their robustness has been largely improved through this automatic transition. This methodology will further expand the practical application of TENGs for long-time usage and for harvesting mechanical energies with fluctuating intensities.

Given a linear system x˙=Ax+Bu with output y=Cx and a window function ω(t) , i.e ., ∀t,ω(t)∈ {0,1 }, and assuming that the window function is Lebesgue measurable, we refer to the following observer, x^=Ax+Bu+ω(t)LC(x−x^) as a window observer. The stability issue is treated in this paper. It is proven that for linear time-invariant systems, the window observer can be stabilized by an appropriate design under a very mild condition on the window functions, albeit for linear time-varying system, some regularity of the window functions is required to achieve observer designs with the asymptotic stability. The corresponding design methods are developed. An example is included to illustrate the possible applications

Detailed analysis the combined effect of N, O heteroatoms on electrochemical performance through N, O-containing Covalent Triazine-Based Frameworks.Image 1

Satellite orbit error is one of main sources in Global Positioning System (GPS) receiver positioning error. Using broadcast ephemeris in navigation message, the receiver can calculate spatial position of GPS satellites, then combine pseudorange measurements and achieve positioning solution. In this work, taking broadcast ephemeris in the 2036th GPS week as an example, orbital position of the satellite with the pseudo-random-noise (PRN) code 4 is calculated. Furthermore, using GPS precision ephemeris as a reference, orbital error of the broadcast ephemeris for the PRN 4 satellite is investigated. The results show that the maximum difference of the satellite in three directions is 36 meters, 57 meters and 39 meters, respectively. The three-dimension distance deviating from precision ephemeris is at most 61 meters. The maximum deviation occurs only during certain time periods in the whole GPS week.