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•Chiral AIE compounds are recently developed very rapidly.•Chiral AIEgens display excellent chiral recognition, ee analysis and CPL properties.•Review paper about preparation of ...chiral AIEgens and their applications is scarce.
Due to immense potential in using as chemo/biosensors and solid emitters, aggregation-induced emission (AIE) phenomenon is attracting huge interest in scientific community. After endowed with chirality, the resultant chiral AIE luminogens (AIEgen), just like a tiger with added wings, can display more and stronger promising functionalities. Moreover, many classic luminophores can be transformed into AIEgens from notorious aggregation-caused quenching (ACQ) compounds as soon as they are attached with chiral groups. Compared with other chiral fluorescent receptors and chiral emitter, chiral AIEgens have displayed unique and outstanding advantages. Firstly, chiral AIEgen can differentiate two enantiomers of chiral analyte by 1.68 × 104 fold difference and get a chiral magnification up to 2.5 × 103 times due to aggregation. In addition, two enantiomers of up to 18 chiral carboxylic acids can be recognized just by using only one chiral AIEgen receptor and enantiomeric excess (ee) of chiral analytes at uM level can be measured. Furthermore, accurate ee analysis was carried out for the first time from fluorescence wavelength change rather than intensity change of the chiral AIEgen receptor. Therefore, the chiral AIEgens show unprecedentedly high selectivity, high sensitivity, high applicability, and high accuracy. Secondly, in the area of organic circularly polarized luminescence (CPL) materials, the CPL dissymmetry factor (glum) of chiral AIEgen can get to 1.42 that is near to the theoretical value of 2, making a breakthrough progress while the |glum| of previous organic luminophores is generally between 10−5 and 10−2. Furthermore, the highly efficient circularly polarized organic light-emitting diodes (CPOLEDs) are constructed for the first time by chiral AIEgens. Thirdly, chiral AIEgens enable novel display technology under different lighting conditions to be possible. More importantly, due to AIE effect, AIEgens are very beneficial for disclosing the mechanism of chiral transfer and magnification between molecules, which is thought to be the key for evolution of homochirality in natural world and preparation of chiral materials with hierarchical structures. For the above reason, chiral AIEgens have been brought to extensive attention and a large number of research works about them are reported. To take an overall view on chiral AIEgens and facilitate the development of chiral AIEgens, it is necessary to make a full review on the chiral AIEgens. This review covers the following contents: (1) construction of chiral AIEgens including propeller-like chiral AIEgens, chiral AIEgens with optically pure groups, polymer chiral AIEgens and supramolecular chiral AIEgen system; (2) chiral recognition and ee determination of chiral carboxylic acids, chiral amines, α-amino acids, and chiral neutral molecules by chiral AIEgens; (3) performance of chiral AIEgens in circular dichroism (CD), CPL and CPOLEDs; (4) other versatile application researches related to chiral AIEgens.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Organic molecules with an aggregation-induced emission (AIE) effect have recently been attracting more and more attention due to their colossal potential in solid emitters and chemo/biosensors. The ...number and variety of AIEgen compounds are expanding very rapidly to obtain better application performance and a wider area of application. Among AIEgen systems, tetraphenylethylene (TPE) and its derivatives are the class that have received the most extensive study and the most rapid development because of their facile synthesis. Due to its
C
2
symmetry and at least tetratopic reaction positions, the TPE unit is also an ideal building block for constructing macrocycles and cages. The resultant cyclic TPE compounds have exhibited many exceptional performances that are difficult to access in their open chain counterparts, such as AIE enhancement, improvement in selectivity and sensitivity as sensors, emission tuning by guests, supramolecular catalysis, further disclosure of the AIE mechanism, molecular adsorption, storage and release, the propeller-like conformation exploitation of the TPE unit in chiral materials and so on. Recently, therefore, a large variety of studies about the synthesis, properties and application research of TPE macrocycles and cages have been reported. These TPE macrocycles and cages significantly expand the research area for the AIE phenomenon and its applications, and represent a development of the AIE area. However, up to now, no review of TPE macrocycles and cages has been available. Thus, this review serves as a summary of the designs, synthesis, photophysical properties, self-assembly, applications and prospects of TPE macrocycles and cages.
Syntheses, photophysical properties and applications of macrocycles and cages based on tetraphenylethylene with aggregation-induced emission (AIE) effect.
A lithium-sulfur (Li-S) battery is regarded as the most promising candidate for next generation energy storage systems, because of its high theoretical specific capacity (1675 mA h g
) and specific ...energy (2500 W h kg
), as well as the abundance, low cost and environmental benignity of sulfur. However, the soluble polysulfides Li
S
(4 ≤ x ≤ 8) produced during the discharge process can cause the so-called "shuttle effect" and lead to low coulombic efficiency and rapid capacity fading of the batteries, which seriously restrict their practical application. Using porous materials as hosts to immobilize the polysulfides is proved to be an effective strategy. In this article, a dual functional cage-like metal-organic framework (Cu-MOF), Cu-TDPAT, combining the Lewis basic sites from the nitrogen atoms of the ligand H
TDPAT with the Lewis acidic sites from Cu(ii) open metal sites (OMSs), was employed as the sulfur host in a Li-S battery for lithium ions and polysulfide anions (S
). In addition, the size of nano-Cu-TDPAT was also optimized by microwave synthesis to reduce the internal resistance of the batteries. The electrochemical test results showed that the optimized Cu-TDPAT material can efficiently confine the polysulfides within the MOF, and the resultant porous S@Cu-TDPAT composite cathode material with the size of 100 nm shows good cycling performance with a reversible capacity of about 745 mA h g
at 1C (1C = 1675 mA g
) after 500 cycles, to the best of our knowledge, which is higher than those of all reported S@MOF cathode materials. The DFT calculation and XPS data indicate that the good cycling performance mainly results from the dual functional binding sites (that is, Lewis acid and base sites) in nanoporous Cu-TDPAT, providing the comprehensive and robust interaction with the polysulfides to overcome their dissolution and diffusion into the electrolyte. Clearly, our work provides a good example of designing MOFs with suitable interaction sites for the polysulfides to achieve S@MOF cathode materials with excellent cycling performance by multiple synergistic effects between nanoporous host MOFs and the polysulfides.
Aberrant topological organization of whole-brain networks has been inconsistently reported in studies of patients with major depressive disorder (MDD), reflecting limited sample sizes. To address ...this issue, we utilized a big data sample of MDD patients from the REST-meta-MDD Project, including 821 MDD patients and 765 normal controls (NCs) from 16 sites. Using the Dosenbach 160 node atlas, we examined whole-brain functional networks and extracted topological features (e.g., global and local efficiency, nodal efficiency, and degree) using graph theory-based methods. Linear mixed-effect models were used for group comparisons to control for site variability; robustness of results was confirmed (e.g., multiple topological parameters, different node definitions, and several head motion control strategies were applied). We found decreased global and local efficiency in patients with MDD compared to NCs. At the nodal level, patients with MDD were characterized by decreased nodal degrees in the somatomotor network (SMN), dorsal attention network (DAN) and visual network (VN) and decreased nodal efficiency in the default mode network (DMN), SMN, DAN, and VN. These topological differences were mostly driven by recurrent MDD patients, rather than first-episode drug naive (FEDN) patients with MDD. In this highly powered multisite study, we observed disrupted topological architecture of functional brain networks in MDD, suggesting both locally and globally decreased efficiency in brain networks.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
An important feature of an inductive power transfer (IPT) system is its power transfer efficiency and capability can be significantly affected by the load and the magnetic coupling variations. ...Therefore, identifying the load and the mutual inductance is essential to improve the system performance. This paper proposes a load and mutual inductance identification method for IPT systems with parallel-compensated power pickups based only on the information detected from the primary side. The proposed method can be implemented for primary resonant circuits whether they are series or parallel tuned, or with a hybrid compensation, such as an LCL configuration. An identification model is established according to the steady-state characteristics of the system. Identification results are obtained based on mathematical derivations and analyses. The proposed identification method is realized without any extra communication or control, and both the simulation and experimental results have verified its feasibility.
Membrane fouling is an important shortcoming limiting the efficiency and wide application of reverse osmosis (RO) technology. In this paper, RO membranes in a full-scale municipal wastewater ...reclamation plant were autopsied. From the lead to tail position RO membranes in RO system, both of organic and inorganic matters on membranes reduced gradually. The higher ion products in RO concentrate didn't result in more serious inorganic scaling on the last position RO membranes, which was contrast with some other researches. Fe, Ca and Mg were major inorganic elements. Fe had a relatively low concentration in RO influent but the highest content on membranes. However, there was no specific pretreatment in terms of Fe removal. Ca and Mg scaling was controlled by the antiscalants injected. Organic fouling (75.0–84.5% of dry weights) was major problem on RO membranes due to the large amount of dissolved organic matters in secondary effluent as raw water. Hydrophilic acid (HIA, 48.0% of total DOC), hydrophobic acid (HOA, 23.6%) and hydrophobic neutral (HON, 19.0%) fraction was largest among the six fractions in RO influent, while HON (38.2–51.1%) and HOA (22.1–26.1%) tended to accumulate on membranes in higher quantities. Monitoring HON and HOA might help to forecast organic fouling.
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•Organic and inorganic fouling reduced from the lead to the tail position RO membranes.•Fe had a low concentration in RO influent but the highest content on RO membranes.•Organic fouling (75.0–84.5% of dry weights) was major problem on RO membranes.•Hydrophilic acid fraction was largest in influent but deposited less on RO membranes.•Hydrophobic neutral and hydrophobic acid tend to deposit excessively on RO membranes.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
A differential-fed gain-enhanced dual-polarized dielectric patch antenna operating at higher order TM 121 and TM 321 modes is investigated in this letter. The introduction of grounded bars in a ...conventional square dielectric patch resonator (DPR) is a key technique in the proposed design. It not only moves the higher order TM 121 mode upwards to enhance the gain of the antenna, but also enables the higher order TM 321 mode to be excited and combined with TM 121 mode to expand the bandwidth. Their corresponding degenerate modes in the DPR are used to generate a dual-polarized operation. By using two identical pairs of differential feeding lines to excite the proposed DPR, several advantages such as high isolation and low cross polarization can be obtained. For demonstration, an antenna prototype centered at about 4.9 GHz is implemented and measured. The simulated and measured results are given, showing a good agreement.
A dielectric patch (DP) resonator (DPR) with silver-coated slots is investigated for designing wideband low-profile antenna in this communication. The low-profile DPR can be treated as an anisotropic ...dielectric resonator (DR) for analysis. A new equation for calculating the effective dielectric constant of the DPR operating at the TM modes is proposed. Based on this, the anisotropic property is investigated to enhance the gain of DP antenna (DPA). It is found from the theoretical analysis that the resultant antenna is a good compromise between the traditional microstrip patch antenna (MPA) and dielectric resonator antenna (DRA) in terms of profile, gain, efficiency, and design freedom. By making full use of the multimode characteristic of the DPR, the silver-coated slots are introduced on the DP to shift high-order TM 121 mode close to TM 101 mode. As a result, the bandwidth of the antenna can be significantly expanded. For demonstration, the DPA element and <inline-formula> <tex-math notation="LaTeX">1\times4 </tex-math></inline-formula> array prototype operating in the microwave band (5 GHz) are implemented and measured.
A novel varactor-loading scheme is proposed for dielectric patch (DP) antenna to design frequency-reconfigurable antenna and array. Benefiting from the stacked structure of the DP antenna, the ...microstrip line is partially inserted between the DP and substrate in a simple way, and the extended part can be used to load the varactor, thereby realizing the function of frequency tunability. At the same time, the loading element has a slight effect on the radiation patterns of the proposed antenna. The impacts of the microstrip line dimensions on frequency tuning range (TR) and radiation efficiency of the antenna are investigated in detail. It is found that an appropriate inserted length of the microstrip line is a key to achieve a good tradeoff between the frequency TR and radiation efficiency. The resultant frequency-reconfigurable DP antenna shows a TR of about 15% and radiation efficiency of more than 50% across the frequency-TR. For demonstration, the DP antenna element and <inline-formula> <tex-math notation="LaTeX">2\times 2 </tex-math></inline-formula> array prototypes operating in the <inline-formula> <tex-math notation="LaTeX">{C} </tex-math></inline-formula>-band are implemented and measured. The simulated and measured results with a good agreement are presented to verify the proposed idea.
Preeclampsia (PE) is a severe hypertension-related disorder occurring during pregnancy that leads to significant mortality and morbidity in both the foetus and mother. Atractylenolide (ATL), a ...traditional Chinese natural agent isolated from the herb Atractylodes macrocephala, exhibits a series of pharmacological activities, including anti-oxidative stress and anti-inflammatory effects.
The impacts of ATL on apoptosis and oxidative stress in HTR-8/SVneo cells during PE development was investigated.
We identified ATL by an overlap analysis of the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) database using the keyword ‘gestational hypertension’ and Traditional Chinese Medicine (Batman-TCM) database using the keyword ‘Atractylodes macrocephala’.
Cell viability, proliferation, and migration were detected by CCK-8, EdU, and transwell assays. Flow cytometry and 2′,7′-dichlorodihydrofluorescein diacetate were used to assess apoptosis and reactive oxygen species (ROS) levels.
EdU and CCK-8 assays demonstrated that ATL significantly enhanced the viability of HTR-8/SVneo cells. Transwell assays showed that ATL remarkably induced the migration of HTR-8/SVneo cells. Moreover, ROS production in HTR-8/SVneo cells was induced by H2O2, whilst ATL alleviated this H2O2-induced ROS production and apoptosis in cells.
ATL attenuated apoptosis and oxidative stress in HTR-8/SVneo cells in PE by activating the MAPK/ERK signalling pathway. ATL has potential to be utilized as a potential therapeutic candidate for PE.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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