In short-chain alkane aromatization catalyzed by metal-modified HZSM-5, the metal cations acting as Lewis acid sites are considered to be the active centres for the dehydrogenation. However, other ...possible effects of the metal cations during the reaction have been neglected. In this study, a combination of experiments and DFT calculations has been carried out to investigate the complete effects of the Zn on ZSM-5 in isobutane aromatization. Zn
8.47
/HZSM-5 (Zn/Al > 1) with weak acidic properties was prepared as a Lewis acid sites-dominated catalyst. It was found that the (Zn-O-Zn)
2+
Lewis acid sites acted as the main active sites and no bridged hydroxyl groups (Brønsted acid sites) were present. In isobutane conversion, it was surprisingly found that Zn
8.47
/HZSM-5 showed better catalytic performance at low temperature than HZSM-5 (Brønsted acid sites-dominated catalyst) and Zn
2.34
/HZSM-5 (Brønsted and Zn-Lewis acid sites co-existing catalyst). DFT calculations and
operando
dual-beam Fourier transform infrared spectrometry (DB-FTIR) characterization were employed to understand how the isobutane aromatization could be catalyzed on the Lewis acid site (Zn-O-Zn)
2+
exclusively without the participation of bridged hydroxyl groups. It was directly observed over DB-FTIR that the Lewis acid-type Zn/HZSM-5 enjoyed a faster aromatization rate and higher stability than HZSM-5 under real aromatization conditions. This firstly testified that the complete reaction of isobutane aromatization could be exclusively catalyzed by (Zn-O-Zn)
2+
Lewis acid sites without the participation of bridged hydroxyl groups. The Zn-(OH)
−
+
species could be produced
in situ
and acted as the Brønsted acid sites. Owing to the weak acidity of Zn-(OH)
−
+
, the Lewis acid sites played a key role during the aromatization reactions
via
the carbanionic mechanism.
Operando
DB-FTIR and DFT results certificate that the isobutane aromatization could be exclusively catalyzed by (Zn-O-Zn)
2+
Lewis acid site over Zn/HZSM-5.
A convenient and efficient Cu(OTf)
2-catalyzed arylation of indolin-2,3-ones with arylboronic acids using cheap 1,10-phenanthroline hydrate as ligand was developed under air atmosphere, achieving ...3-aryl-3-hydroxy-2-oxindoles in good to excellent yields. This catalytic system shows broad functional group tolerance. Moreover, the rigorous exclusion of air/moisture is not required in these transformations.
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The battery power state (SOP) is the basic indicator for the Battery management system (BMS) of the battery energy storage system (BESS) to formulate control strategies. Although there have been many ...studies on state estimation of lithium-ion batteries (LIBs), aging and temperature variation are seldom considered in peak power prediction during the whole life of the battery. To fill this gap, this paper aims to propose an adaptive peak power prediction method for power lithium-ion batteries considering temperature and aging is proposed. First, the Thevenin equivalent circuit model is used to jointly estimate the state of charge (SOC) and SOP of the lithium-ion power battery, and the variable forgetting factor recursive least squares (VFF-RLS) algorithm and extended Kalman filter (EKF) are utilized to identify the battery parameters online. Then, multiple constraint parameters including current, voltage, and SOC were derived, considering the dependence of the polarization resistance of the battery on the battery current. Finally, the verification experiment was carried out with LiFePO4 battery. The experimental results under FUDS operating conditions show that the maximum SOC estimation error is 1.94%. And the power prediction errors at 20%, 50%, and 70% SOC were 5.0%, 8.1% and 4.5%, respectively. Our further work will focus on the joint estimation of battery state to further improve the accuracy.
The glycosylation pattern of alpha fetoprotein (AFP) paves the basis for precise early diagnosis of hepatocellular carcinoma (HCC). However, existing analytical methods ignore the contribution of ...terminal sialic acid, which has been reported to be highly connected with HCC. Besides, the development of diagnostic assays is severely hindered by the preparation of anti‐glycans antibodies. Molecularly imprinted polymers (MIPs), as synthetic antibody mimics, provide unique strengths to address these issues. Herein, we report a MIPs‐based dual‐modal ratiometric immunoassay for precise HCC diagnosis. Using a “pit one against ten” MIP to recognize a subset of glycans containing sialic acid and/or core fucose, we demonstrated our assay exhibited improved precision as compared with ELISA. This assay provided not only a glycoform‐resolved method for precise HCC diagnosis, but also a new paradigm for developing antibody mimics via molecular imprinting towards challenging biomedical applications.
By taking both terminal sialic acid and core fucose into account, a molecularly imprinted polymers (MIPs)‐based dual‐modal ratiometric immunoassay was developed for the precise diagnosis of hepatocellular carcinoma (HCC). Three MIPs orthogonally recognize the N‐terminal epitope, C‐terminal epitope and glycans of glycoprotein biomarkers, and dual‐modal detection provides two independent glycans/glycoprotein values, enabling self‐validating, high‐contrast, and more precise diagnosis compared to antibodies‐based methods.
Sensory modalities are important for survival but the molecular mechanisms remain challenging due to the polymodal functionality of sensory neurons. Here, we report the
C. elegans
outer labial ...lateral (OLL) sensilla sensory neurons respond to touch and cold. Mechanosensation of OLL neurons resulted in cell-autonomous mechanically-evoked Ca
2+
transients and rapidly-adapting mechanoreceptor currents with a very short latency. Mechanotransduction of OLL neurons might be carried by a novel Na
+
conductance channel, which is insensitive to amiloride. The
bona fide
mechano-gated Na
+
-selective degenerin/epithelial Na
+
channels, TRP-4, TMC, and Piezo proteins are not involved in this mechanosensation. Interestingly, OLL neurons also mediated cold but not warm responses in a cell-autonomous manner. We further showed that the cold response of OLL neurons is not mediated by the cold receptor TRPA-1 or the temperature-sensitive glutamate receptor GLR-3. Thus, we propose the polymodal functionality of OLL neurons in mechanosensation and cold sensation.
This paper proposes a new approach for investigating the mechanism of the formation of the active phase of a hydrodesulfurization (HDS) catalyst
via
crystalline polyoxometalate (POM) precursors. The ...proposed strategy induces the crystallization of small Ni-Mo-O clusters in an impregnating solution by the coordinate bonding and supramolecular interaction of organic ligands to form POMs. By exploiting the "ligand-induced self-assembly" strategy, two Ni-Mo binary POMs with different frameworks, namely, Mo
2
Ni and PMo
11
Ni, were isolated from the impregnating solution by means of 4,4′-bpy. The sulfidation process of the precursors and the formation mechanism of the NiMoS active phase were fully characterized by a multi-technique approach that comprised, in particular,
in situ
FT-IR spectroscopy, XRD and Raman spectroscopy for different degrees of sulfidation. The results of the characterization revealed the structure-directing effects (framework effect, promoting effect and ligand effect) of the POM precursors on the structure of the active phase and even its HDS performance. MoS
2
was formed at 200 °C from Mo
2
Ni, and the Ni species interacted with the edges of MoS
2
to form the NiMoS active phase, whereas PMo
11
Ni formed MoS
2
at 300 °C. The structure-directing effects enabled a higher content and better dispersion of the NiMoS active phase, which explains the higher HDS reactivity of sulfided Mo
2
Ni. The bottom-up self-assembly approach not only provides a better understanding of the composition of the impregnating solution and the formation mechanism of the NiMoS active phase but also sheds light on the rational design and controllable preparation of NiMoS catalysts with high performance.
This paper proposes a new approach for investigating the mechanism of the formation of the active phase of a hydrodesulfurization (HDS) catalyst
via
crystalline polyoxometalate (POM) precursors.
The elevated open-circuit voltage (V oc) observed in silicon heterojunction solar cells is ascribed to the excellent passivation of the amorphous–crystalline silicon interface. This study employs a ...dual-layer intrinsic amorphous silicon passivation layer, supplemented with intermediate hydrogen plasma treatment (HPT), which enhances the passivation effectiveness and simultaneously augments the fill factor (FF) of the solar cell. Fourier transform infrared (FTIR) spectroscopy indicates that HPT leads to an increase in the film’s hydrogen content while concomitantly diminishing the microstructure factor. Simulation and solar cell performance further elucidate that HPT exerts influence on the tunneling mechanisms involved in charge carrier transport, resulting in a heightened FF. Upon the incorporation of HPT, the V oc increased by 19.1 mV and the photoelectric conversion efficiency (PCE) increased by 0.65%.
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