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•The paper based microfluidic platform provided a simple, robust and user-friendly way for multiplexed detection Cu2+ and Hg2+ ions.•This method can realize the liquid phase of ...QDs@IIPs being transferred to the solid glass fiber paper and improve the portability of the device.•The real samples were successfully analyzed with good sensitivity, selectivity and reliability.
In this study, a novel three-dimensional (3D) origami ion imprinted polymers microfluidic paper-based chip device for specific, sensitive and multiplexed detection of Cu2+ and Hg2+ ions has been proposed. In this device, the surface of the paper was activated by grafting with CdTe QDs through amino processing and formation of Cu2+ or Hg2+ IIPs and CdTe QDs complex that led to fluorescence quenching of QDs because the photo luminescent energy of QDs could be delivered to the complex. This method can realize the liquid phase of QDs@IIPs being transferred to the solid glass fiber paper and improve the portability of the device. Moreover, this platform allows to simultaneous detection of Cu2+ and Hg2+ ions with good selectivity and sensitivity. The proposed method reveals that the copper ion imprinted fluorescent sensor demonstrated a good linearity from 0.11 to 58.0μg/L with the detection limit of 0.035μg/L and the mercury ion linear range is 0.26–34.0μg/L with detection limit of 0.056μg/L. Importantly, this device can provide quantitative information conveniently and show great potential to be further extended to the detection of other metal ions for environmental monitoring and food safety field.
Aqueous Zn batteries have drawn tremendous attention for their several advantages. However, the challenges of Zn anodes such as the corrosion and ZnO densification have compromised their application ...in rechargeable Zn‐based batteries. In this paper, a straightforward strategy is employed to facilitate the uniform Zn stripping/plating of the Zn anode through using a ZrO2 coating layer, which contributes to the controllable nucleation sites for Zn2+ and fast Zn2+ transportation through the favorable Maxwell–Wagner polarization. As a result, the low polarization (24 mV at 0.25 mA cm−2), high Coulombic efficiency (99.36% at 20 mA cm−2), and long cycle life (over 3800 h at 0.25 mA cm−2) can be obtained for the ZrO2‐coated Zn anode. It is believed that the ZrO2 coating layer can also act as an inert physical barrier to decrease the contact of the anode and electrolyte, thus reducing both the Zn corrosion and formation of ZnO densification, and then improve the reversibility of Zn anode. The results demonstrated in this work provide an appealing strategy for the future development of rechargeable Zn‐based batteries.
A highly reversible Zn anode is achieved through controllable nucleation sites for Zn2+ and fast Zn2+ transportation under the favorable Maxwell–Wagner polarization, in which a low polarization (24 mV), high Coulombic efficiency (99.36%), and long cycle life (over 3800 h) are obtained by employing a ZrO2‐coating layer.
As an emerging interdisciplinary field in anthropology, enterprise anthropology (EA) has experienced five historical stages of development since its inception in the 1930s. 2008 marked the first year ...of internationalized enterprise anthropology, thus prompting the “fourth revolution” of anthropology. Since then, the sub-discipline of enterprise anthropology has entered its fifth stage of development. This stage of enterprise anthropology has witnessed new research subjects, concepts, and theories. Breakthroughs have been made in theoretical research and methodological innovation, and a unique paradigm has been established. In terms of discipline and era, the fifth stage is characterized by: innovative transformation and creative development, integration of Chinese and Western channels for anthropology research, building of international academic networks, and the practice of “people-centered” research. As a result, this stage of enterprise anthropology holds profound theoretical and practical significance for interdisciplinary and academic equity, new ideas and methods for studying the transformation of Chinese society, and establishment of an internationalized research paradigm for the Chinese academic community.
This paper presents a system, where clocked comparators consuming only CV 2 energy directly derive classification decisions from analog sensor signals, thereby replacing instrumentation amplifiers, ...ADCs, and digital MACs, as typically required. A machine-learning algorithm for training the classifier is presented, which enables circuit non-idealities as well as severe energy/area scaling in analog circuits to be overcome. Furthermore, a noise model of the system is presented and experimentally verified, providing a means to predict and optimize classification error probability in a given application. The noise model shows that superior noise efficiency is achieved by the comparator-based system compared with a system based on linear low-noise amplifiers. A prototype in 130-nm CMOS performs image recognition of handwritten numerical digits, by taking raw analog pixels as the inputs. Due to pin limitations on the chip, the images with 28 × 28 = 784 pixels are resized and downsampled to give 47 pixel features, yielding an accuracy of 90% for an ideal ten-way classification system (MATLAB simulated). The prototype comparator-based system achieves equivalent performance with a total energy of 543 pJ per ten-way classification at a rate up to 1.3 M images per second, representing 33× lower energy than an ADC/digital-MAC system.
Hydronium-ion batteries are regarded as one of the most promising energy technologies as next-generation power sources, benefiting from their cost effectivity and sustainability merits. Herein, we ...propose a hydronium-ion battery which is based on an organic pyrene-4,5,9,10-tetraone anode and an inorganic MnO
@graphite felt cathode in an acid electrolyte. Its operation involves a quinone/hydroquinone redox reaction on anode and a MnO
/Mn
conversion reaction on cathode, in parallel with the transfer of H
O
between two electrodes. The distinct operation mechanism affords this hydronium-ion battery an energy density up to 132.6 Wh kg
and a supercapacitor-comparable power density of 30.8 kW kg
, along with a long-term cycling life over 5000 cycles. Furthermore, surprisingly, this hydronium-ion battery works well even with a frozen electrolyte under -40 °C, and superior rate performance and cycle stability remain at -70 °C.
Necroptosis and pyroptosis are two forms of programmed cell death with a common feature of plasma membrane rupture. Here we studied the morphology and mechanism of pyroptosis in comparison with ...necroptosis. Different from necroptosis, pyroptosis undergoes membrane blebbing and produces apoptotic body-like cell protrusions （termed pyroptotic bodies） prior to plasma membrane rupture. The rupture in necroptosis is explosion-like, whereas in pyroptosis it leads to flattening of cells. It is known that the execution of necroptosis is mediated by mixed lineage kinase domain-like （MLKL） oligomers in the plasma membrane, whereas gasdermin-D （GSDMD） mediates pyroptosis after its cleavage by caspase-1 or caspase-11. We show that N-terminal fragment of GSDMD （GSDMD-N） generated by caspase cleavage also forms oligomer and migrates to the plasma membrane to kill cells. Both MLKL and GSDMD-N are lipophilic and the N-terminal sequences of both proteins are important for their oligomerization and plasma membrane translocation. Unlike MLKL which forms channels on the plasma membrane that induces influx of selected ions which osmotically swell the cells to burst, GSDMD-N forms non-selective pores and does not rely on increased osmolarity to disrupt cells. Our study reveals the pore-forming activity of GSDMD and channel-forming activity of MLKL determine different ways of plasma membrane rupture in pyroptosis and necroptosis.
The effective thermal conductivity (ETC) plays an important role in many fields such as to solve basic geological problems, rock engineering, and utilization of heat energy; ETC is one of the most ...important thermo-physical properties of porous media. In this study, experiments on synthetic rock samples with different material mixture ratios under different operating temperatures are conducted to estimate the thermal conductivity property of the rock samples. The experiments were performed on synthetic samples with different ratios of gypsum, fine or medium sand, and water; 21 groups of tests were conducted under room temperature; another five groups of tests were conducted under different temperatures from 20 to 50 ° to assess the effect of temperature on thermal conductivity. According to existing studies and equations, thermal conductivity increases with an increase of sand content and a decrease in temperature. Moreover, based on our experiments, it is easy to identified a singularity on the general changing trend of thermal conductivity for each sample. Following our experimental results, we attempted to observe and interpret this alteration mechanism. According to the heat capacity theory in solid-state physics, this research provides new explanations for the above alteration.
In recent years, gold nanoparticles (AuNPs) have drawn considerable research attention in the fields of catalysis, drug delivery, imaging, diagnostics, therapy and biosensors due to their unique ...optical and electronic properties. In this review, we summarized recent advances in the development of AuNP-based colorimetric and fluorescent assays for ions including cations (such as Hg
2+
, Cu
2+
, Pb
2+
, As
3+
, Ca
2+
, Al
3+
,
etc
) and anions (such as NO
2
−
, CN
−
, PF
6
−
, F
−
, I
−
, oxoanions), and small organic molecules (such as cysteine, homocysteine, trinitrotoluene, melamine and cocaine, ATP, glucose, dopamine and so forth). Many of these species adversely affect human health and the environment. Moreover, we paid particular attention to AuNP-based colorimetric and fluorescent assays in practical applications.
We review recent advances in the development of AuNP-based colorimetric and fluorescent assays for ions and small organic molecules.
Current photocatalytic semiconductors often have low catalytic performance due to limited light utilization and fast charge carrier recombination. Formation of Schottky junction between ...semiconductors and plasmonic metals can broaden the light absorption and facilitate the photon‐generated carriers separation. To further amplify the catalytic performance, herein, an asymmetric gold‐zinc oxide (Asy‐Au−ZnO) nanorod array is rationally designed, which realizes the synergy of piezocatalysis and photocatalysis, as well as spatially oriented electron−hole pairs separation, generating a significantly enhanced catalytic performance. In addition to conventional properties from noble metal/semiconductor Schottky junction, the rationally designed heterostructure has several additional advantages: 1) The piezoelectric ZnO under light and mechanical stress can directly generate charge carriers; 2) the Schottky barrier can be reduced by ZnO piezopotential to enhance the injection efficiency of hot electrons from Au nanoparticles to ZnO; 3) the unique asymmetric nanorod array structure can achieve a spatially directed separation and migration of the photon‐generated carriers. When ultrasound and all‐spectrum light irradiation are exerted simultaneously, the Asy‐Au−ZnO reaches the highest catalytic efficiency of 95% in 75 min for dye degradation. It paves a new pathway for designing unique asymmetric nanostructures with the synergy of photocatalysis and piezocatalysis.
An asymmetric Au−ZnO nanorod array is developed for efficient separation of photon‐generated charge carriers with assistance of piezophototronic effect. The unique asymmetric structure can significantly enhance the spatially directed migration and separation of the photon‐generated carriers with assistance of piezophototronic effect, and further realize enhanced catalytic activity by the synergy of piezocatalysis and photocatalysis.
This paper investigates the issue of finite-time state estimation for coupled Markovian neural networks subject to sensor nonlinearities, where the Markov chain with partially unknown transition ...probabilities is considered. A Luenberger-type state estimator is proposed based on incomplete measurements, and the estimation error system is derived by using the Kronecker product. By using the Lyapunov method, sufficient conditions are established, which guarantee that the estimation error system is stochastically finite-time bounded and stochastically finite-time stable, respectively. Then, the estimator gains are obtained via solving a set of coupled linear matrix inequalities. Finally, a numerical example is given to illustrate the effectiveness of the proposed new design method.
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