This paper proposes a new extended state observer-based sliding-mode control strategy with prescribed-time convergence. Firstly, a novel prescribed-time extended state observer is designed, which ...estimates the disturbance accurately within a prescribed time and effectively solves peaking value problem. Secondly, a new type of second-order prescribed-time sliding-mode controller is designed to ensure system states converge within a prescribed time. Then, the proposed control strategy is applied to the design of partial integrated guidance and control with two-loop controller structure. Finally, the validity of the proposed methodology is verified through numerical simulation.
Besides serving as a low-toxicity, inexpensive and easily accessible solvent, dimethyl sulfoxide (DMSO) has also been extensively used as a versatile reagent for the synthesis of functionalized ...molecules. Dimethyl sulfoxide can not only be utilized as a carbon source, a sulfur source and an oxygen source, but also be employed as a crucial oxidant enabling various transformations. The past decade has witnessed a large number of impressive achievements on the direct synthesis of heterocycles as well as modifications of heterocyclic compounds by applying DMSO as a reagent. This review summarized the DMSO-based direct heterocycle constructions from 2012 to 2022.
Considering the wide occurrence and extensive application of organic chlorides in many research fields, the development of easy, practical and green chlorination methodologies is much needed. In the ...oxidative chlorination strategy, active chlorinating species can be
in situ
formed by the interaction of easily accessible chlorides such as NaCl, HCl, KCl, CHCl
3
,
etc.
and suitable oxidants. Among the established chlorination approaches, this strategy is an attractive one as it features the use of readily available, cheap and safe inorganic or organic chlorides, good atom economy of chlorine, and multiple choices of oxidants. This review summarizes the representative methodologies in the field of oxidative chlorination, covering 2013 to 2023.
This review summarizes the representative methodologies in the field of oxidative chlorination, covering 2013 to 2023.
Al
0.17
V
2
O
5
(H
2
O)
2
·H
2
O (AlVO) and Ca
0.23
V
2
O
5
(H
2
O)·H
2
O (CaVO) are synthesized herein, and their Rietveld refinements reveal that they are composed of V-O-V layers, lamellar ...hydrated Al
3+
or Ca
2+
and dissociated water molecules. The preintercalation of metal ions into V
2
O
5
leads to the elongation of V-O bonds, and all the V centers are unsaturated coordinated. The V-O-V bilayer in V
2
O
5
is split into two discrete V-O-V monolayers with the (001) facet as the division plane. Meanwhile, the exposed V centers on the (001) surface are unsaturated with oxygen vacancies, which can facilitate the migration of Zn
2+
along the (001) surface of AlVO with a lower energy barrier of 0.88 eV, as evidenced by density functional theory (DFT) simulations. AlVO shows a dominant pseudocapacitive behavior with excellent rate capability and outstanding cycling performance. It can deliver a high capacity of 441 mA h g
−1
at 0.1 A g
−1
with capacity retentions of 96.7% and 90.5% after 1000 and 2000 discharge/charge cycles at 5 A g
−1
, respectively, which are superior to that of CaVO. In addition, DFT calculations also reveal that the intercalation of Zn
2+
on some sites in the interlayer channels of AlVO and CaVO is irreversible with very negative binding energies, leading to the accumulation of Zn
2+
in AlVO and CaVO. Furthermore,
ex situ
characterization of AlVO and quasi-reversible change of the pH value during the 1
st
discharge/charge process indicate a co-(de)intercalation mechanism of H
+
and Zn
2+
. The pH-induced V species and the accumulation of Zn
2+
give rise to partial transformation of AlVO → Al
3+
-doped Zn
3
(OH)
2
V
2
O
7
·2H
2
O, which is also observed for CaVO.
Aluminium vanadate with unsaturated coordinated V centers and oxygen vacancies shows excellent Zn
2+
storage due to the low Zn
2+
migration barrier along the (001) surface, the co-(de)intercalation mechanism of H
+
/Zn
2+
and the partial transformation.
Pyrrolo2,1-
a
isoquinolines occur frequently in a large number of bioactive natural products and pharmaceutically important molecules. The synthesis of pyrrolo2,1-
a
isoquinoline derivatives is an ...easy and useful way to produce artificial molecules with potential applications. A huge number of excellent methodologies for constructing pyrrolo2,1-
a
isoquinolines have been reported in the last decade. This review summarizes the recent advances in this research field covering from 2011 to 2021.
This review summarizes the recent advances in the research field of pyrrolo2,1-
a
isoquinolines synthesis covering from 2011 to 2021.
The transformation of (hetero)arene cation radicals has become a powerful tool for the construction of highly functionalized (hetero)arenes. These (hetero)arene cation radicals could be generated ...under electrochemical, photochemical or chemical oxidation systems. The
in situ
generated (hetero)arene cation radicals can be attacked by various nucleophiles, such as (hetero)aromatics and anions, yielding structurally diverse molecules. Recently, a large number of impressive heteroarene modifications have been designed by this strategy. This review summarizes the advances in heteroarene modification
via
reactions of
in situ
formed (hetero)arene cation radicals, ranging from 2010 to 2020.
This review summarizes the advances in heteroarene modification
via
transformations of
in situ
generated (hetero)arene cation radicals, ranging from 2010 to 2020.
Organic co‐crystal engineering is a promising method to make multifunctional materials. Here, the marriage of macrocyclic chemistry and co‐crystal engineering provides a smart strategy to build ...vapochromic materials. The macrocycle co‐crystals (MCCs) were constructed from π‐electron rich pillar5arene (P5) and an electron‐deficient pyromellitic diimide derivative (PDI) on a 10 g scale. MCCs of P5‐PDI are in red owing to the formation of a charge‐transfer (CT) complex. After solvent removal, a white crystalline solid with a new structure (P5‐PDIα) is yielded, which exhibits selective vapochromic responses to volatile organic compounds (VOCs) of haloalkanes, accompanied by color changes from white to red or orange. Powder and single‐crystal X‐ray diffraction analyses reveal that the color changes are attributed to the vapor‐triggered solid‐state structural transformation to form CT co‐crystals. Coating films of P5 and PDI on glass showed a visible vapochromic behavior with good reversibility.
A smart strategy to build functional materials was designed through the marriage of macrocyclic chemistry and co‐crystal engineering. The resulting macrocycle co‐crystals (MCCs), P5‐PDIα exhibit selective vapochromic responses to volatile organic compounds of haloalkanes, accompanied by color changes from white to red or orange and vapor‐triggered solid‐state structural transformation to form charge‐transfer co‐crystals.
We have developed a straightforward FeCl3 promoted synthesis of dihydropyrrolo2,1‐aisoquinolines through formal (3+2) cycloaddition/oxidative aromatization cascade of dihydroisoquinoline with ...Morita‐Baylis‐Hillman carbonates (up to 96% yield). Further modifications of the obtained products were successful through simple chemical transformations providing a diverse range of natural product‐like molecules (12 examples).
Radio Frequency Identification (RFID) sensors, integrating the features of Wireless Information and Power Transfer (WIPT), object identification and energy efficient sensing capabilities, have been ...considered a new paradigm of sensing and communication for the futuristic information systems. RFID sensor tags featuring contactless sensing, wireless information transfer, wireless powered, light weight, non-line-of-sight transmission, flexible and pasteable are a critical enabling technology for future Internet-of-Things (IoT) applications, such as manufacturing, logistics, healthcare, agriculture and food. They have attracted numerous research efforts due to their innovative potential in the various application fields. However, there has been a gap between the in-lab investigations and the practical IoT application scenarios, which has motivated this survey of this research to identify the promising enabling techniques and the underlying challenges. This study aims to provide an exhaustive review on the state-of-art RFID sensor technologies from the system implementation perspective by focusing on the fundamental RF energy harvesting theories, the recent technical progresses and commercial solutions, innovative applications and some RFID sensor based IoT solutions, identify the underlying technological challenges at the time being, and give the future research trends and promising application fields in the rich sensing applications of the forthcoming IoT era.
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