Search

Fluorene is a classic three-membered polycyclic aromatic hydrocarbon, and it has been widely used in optoelectronic devices. Here we explore a simple and efficient strategy for the derivatization at the 2- and 3- positions in fluorene unit. By introducing different types of substituents, we design two pairs of 2,3-disubstituted fluorene isomers and use them as host materials for phosphorescent organic light-emitting diodes (PHOLEDs). The green PHOLEDs hosted by these fluorene derivatives realize high external quantum efficiencies (EQE) over 20 % with low efficiency roll-off. Particularly, the devices hosted by 2TRz3TPA and 2TPA3TRz achieve nearly 24 % EQE and 104 lm W

To discuss the application principle in tuina manipulation for lumbar intervertebral disc herniation (UDH) in Chinese literatures published in recent 30 years. The three major Chinese databases, Wanfang Academic Journal Full-text Database (Wanfang), Chongqing VIP Database (CQVIP) and China National Knowledge Infrastructure (CNKI), were searched to collect the studies of tuina manipulations in treatment of LIDH published in recent 30 years. Clustering analysis was applied to analyze the top 20 tuina manipulations for UDH. The top 20 most frequently used manipulations for LIDH were Gun-rolling, Rou-kneading, Dian-digital pressing, oblique Ban-pulling, An-pressing, Tanbo-plucking, Bashen-pulling and extending, horizontal Tui-pushing, Na-grasping, Anrou-pressing and kneading, Dou-shaking, Yao-rocking, Ca-scrubbing, Pai-patting, post-extension Ban-pulling, Mo-rubbing, Zhen-vibrating, Nie-pinching, fist-back Ji-tapping, and dorsal Shen-extending methods. The involved manipulations can be divided into two categories by the treated body areas. One category is applied to the soft tissues, including Gun-rolling, Rou-kneading, Dian-digital pressing, An-pressing, Tanbo-plucking, horizontal Tui-pushing, Na-grasping, Anrou-pressing and kneading, Ca-scrubbing, Pai-patting, Mo-rubbing, Zhen-vibrating, Nie-pinching, and fist-back Ji-tapping methods. The other category is applied to bones and joints, including oblique Ban-pulling, Bashen-pulling and extending, Dou-shaking, Yao-rocking, post-extension Ban-pulling, and dorsal Shen-extending methods. Based on the treated body area, the tuina manipulations applied to treat LIDH are predominated by the ones performed on soft tissues, assisted by those on bones and joints. From the way of force exertion, the involved manipulations are majorly the swinging methods, followed by squeezing and pressing ones. The manipulations applied to bones and joints are predominated by the Ban-pulling ones, followed by the Bashen-pulling and extending ones.

Nanozymes as artificial enzymes that mimicked natural enzyme-like activities have received great attention in cancer diagnosis and therapy. Biomimetic nanozymes require more consideration regarding complicated tumor microenvironments to mimic biological enzymes, thus achieving superior nanozyme activity in vivo. Here we report a biomimetic hybrid nanozyme (named rMGB) which integrates natural enzyme glucose oxidase (GOx) with nanozyme manganese dioxide (MnO

An organic ligand 4-(1,2,4-triazol-1-yl) benzoic acid (Htzbc) with a nonlinear optical (NLO) chromophore has been synthesized. Reaction of Zn(NO3)2 with Htzbc ligand in 1-n-butyl-3-methylimidazolium tetrafluoroborate ionic liquid afforded compound Zn(tzbc)2 (1). The Htzbc organic solid and 1 crystallize in the acentric Pn and Cc space groups, respectively. The tetrahedral Zn2+ center in 1 coordinates to two triazole nitrogen atoms and two carboxylate oxygen atoms from four tzbc– ligands, leading to a noncentrosymmetric 5-fold interpenetrating diamondoid network. Second-harmonic generation (SHG) measurements revealed the Htzbc solid and 1 have SHG activities. The Htzbc compound has a large SHG effect, which is approximately 3 times that of KDP and is type-I phase matchable, while 1 also belongs to phase-matchable class with a SHG response of about 1.2 times that of KDP. The SHG active of the organic solid can be derived from the inherently dipolar Htzbc molecule as well as the optimal relative orientation ...

Compound {(EMIM)2[Zn7(μ4-O)2(1,4-ndc)6]}n (1) (EMIM = 1-ethyl-3-methylimidazolium and 1,4-ndc = 1,4-naphthalenedicarboxylate) has been synthesized by using the mixed ionic liquids of 1-ethyl-3-methylimidazolium tetrafluoroborate and 1-ethyl-3-methylimidazolium l -lactate as solvent. Compound 1 has a 3D anionic framework with bcu-(424·64) topology based on a unique heptanuclear [Zn7(μ4-O)(μ2-COO)10] cluster as secondary building unit. The imidazolium cation [EMIM]+ of the ionic liquid acting as extra framework charge-balancing species occupies the channels of the 3D anionic framework. The roles of the ionic liquid in ionothermal synthesis and crystallization of compound 1 are briefly discussed. The thermal and photoluminescent properties of compound 1 have also been investigated.

Two homochiral enantiomers {(EMIM)[Zn(SIP)(IM)]}n (1a and 1b, EMIM = 1-ethyl-3-methylimidazolium) possessing chiral (10,3)-a topology constructed from an achiral rigid 5-sulfoisophthalate (SIP) ligand and imidazole (IM) have been obtained by spontaneous resolution under ionothermal conditions. The homochiral enantiomers show second-order nonlinear optical effects and photoluminescence.

Three new coordination compounds with 4-sulfophthalic acid (H3SPA) ligand, namely {[Pb3(4-SPA)2(H2O)](H2O)}n (1), [Mn(4,4′-bpy)2(H2O)4][Mn2(4-SPA)2-(4,4′-bpy)4(H2O)4]·7.5(H2O) (2) and Cu2(4-HSPA)2(2,2′-bpy)2(H2O)2 (3) (4,4′-bpy = 4,4′-bipyridine and 2,2′-bpy = 2,2′-bipyridine), have been synthesized. The structures exhibit different dimensionality depending on the nature of the metal ions and/or the ancillary ligands. Compound 1 has a 2D layered architecture constructed from one-dimensional inorganic lead(II) oxygen chains containing tetranuclear [Pb4(μ2-O)4] cluster. Compound 2 has a dinuclear manganese [Mn2(4-SPA)2(4,4′-bpy)4(H2O)4] motif charged with mononuclear [Mn(4,4′-bpy)2(H2O)4]2+ cation. Compound 3 is a discrete dinuclear copper(II) structure that linked by extensive hydrogen bonds to form a three-dimensional supramolecular structure. In the solid state, compound 1 exhibits blue photoluminescence with the maximum at 432 nm upon excitation at 350 nm. The temperature-dependent magnetic susceptibility data of 2 have been investigated. The Curie constant C and Weiss constant θ are 3.14 emu K mol−1 and −2.09 K, respectively, revealing antiferromagnetically magnetic interactions between the Mn2+ ions. In addition, these compounds are characterized by powder X-ray diffraction, IR, elemental analysis, and thermogravimetric analysis.

The isothiocyanate 3, obtained from aza‐Wittig reaction of iminophosphorane 2 with CS2, reacts with phenylhydrazine to give thiosemicarbazide 4. Reactions of 4 with alkyl halides in the presence of K2CO3 directly provided 2‐alkylthio‐4H‐imidazol‐4‐ones 6 in good yields.

Compound [(EEIM)NaCu(phth)2]n (1) (EEIM = 1,3-diethylimidazolium and phth = terephthalate) was synthesized by using the mixed ionic liquids of 1-ethyl-3-methylimidazolium tetrafluoroborate [EMIM]-BF4 and chiral 1-ethyl-3-methylimidazolium l -lactate as solvent. The sodium(I) ion deriving from the [EMIM]-BF4 with a small amount of Na(I) impurity incorporated into the structure is unprecedented. Compound 1 is a 3D anionic framework based on a unique rod shaped heterometallic copper(II)–sodium(I)-carboxylate secondary building unit, exhibiting a distorted pcu-(412 · 63) topology. It is interesting that the organic template of [EEIM]+ cation formed from an in situ reaction acting as extraframework charge-balancing species occupies the 1D rhombic channels of the 3D anionic framework. The roles of the ionic liquid in ionothermal synthesis and crystallization of 1 are briefly discussed.

Firstly, the factors influencing industrial electric power demand are analyzed. Secondly, the changing law of power consumption intensity and the character of industrial electric power consumption are studied based on the power consumption and the value of industrial output. Finally, a model of power demand is established based on panel data, in which the influence of policy of saving energy is considered. Compared with other models, it is more valid and it can provide decision making support for the forecasting of industrial electric power demand and policy of saving energy in China.

The isothiocyanate 3, obtained from aza‐Wittig reaction of iminophosphorane 2 with CS2, reacts with phenylhydrazine to give thiosemicarbazide 4. Reactions of 4 with alkyl halides in the presence of K2CO3 directly provided 2‐alkylthio‐4H‐imidazol‐4‐ones 6 in good yields.

In the title compound, C14H19N3O, inter­molecular N—H⋯O hydrogen bonds form an infinite chain along the a axis. Electron delocalizition affects the C—N bonds.

Four novel silver(i) and lead(ii) halide compounds with the 4-methyl-1,2,4-triazole-3-thiol (Hmptrz) ligand, namely [Ag2(mptrz)(μ3-X)]n (X = I (1) and Br (2)) and [Pb4(μ4-O)(mptrz)4(μ2-X)2] (X = I (3) and Cl (4)), have been synthesized and characterized. The structures exhibit different dimensionality depending on the nature of the metal ions. Compounds 1 and 2 are isomorphous and have 2D layered structures based on inorganic [Ag2X2]n infinite chains (X = I and Br), in which the mptrz– ligand displays a novel pentadentate bridging coordination mode. Compounds 3 and 4 have similar structures and are composed of a discrete tetranuclear lead(ii) cluster featuring an oxygen-centred Pb4(µ4-O) tetrahedron. Compounds 1 and 2 display solid-state photoluminescent emission with the maximum at 589 and 420 nm respectively. Compounds 3 and 4 show solid-state photoluminescent emission with the maximum at 710 and 540 nm respectively. Additionally, compounds 1–4 were characterized by IR, elemental analysis, powder X-ray diffraction and thermogravimetric analysis.

Hydro(solvo)thermal reactions of cadmium(II) salts with 4-methyl-1,2,4-triazole-3-thiol (Hmptrz) afforded six novel cadmium(II) coordination polymers, namely, [Cd(mptrz)2]n (1), [Cd(mptrz)X]n (X = Br (2) and I (3)), [Cd(mptrz)(μ2-X)]n (X = Br (4) and Cl (5)), and [Cd3(μ3-OH)2(mptrz)4]n (6). Compound 1 is a 1D looped chain structure. Compounds 2 and 3 are isostructural and have 1D ladder structures. Compounds 4 and 5 are isomorphs and feature 2D layered structures. Cadmium(II) bromide formed 1D ladder of 2 and 2D layer of 4, representing an unusual example of Br bond isomerism. Compound 6 has a 1D tape structure with an uncommon 1D inorganic ⋯Cd2(μ3-OH)2–Cd–Cd2(μ3-OH)2⋯ chain. The structural diversity of these materials is reflected in the variety of coordination polyhedra displayed by the cadmium sites: tetrahedral; trigonal bipyramidal; octahedral. The solid state photoluminescence of all compounds have been investigated. However, only compound 6 exhibits photoluminescence with an emission maximum at 435 nm upon excitation at 346 nm. Solid-state density functional theory (DFT) calculations were performed on compound 6. In addition, these compounds were characterized by IR, elemental analysis, and thermogravimetric analysis.

Solvothermal reactions of zinc acetate, sodium hydroxide, and sulfosuccinic acid (H3SSC) in alcohol/H2O, afforded two new three-dimensional (3D) heterometallic sulfonate-carboxylate frameworks, namely, [Na2Zn3(μ3-OH)2(SSC)2(H2O)4]n (1) and [Na4Zn(SSC)2(H2O)3.5]n (2). Compound 1 contains 2D anionic [Zn3(μ3-OH)2(SSC)2]2− layers based on the centrosymmetric mononuclear [Zn(SSC)2]4− units, while compound 2 has 2D anionic [NaZn(SSC)2]3− layers based on the [Zn2(SSC)2] macrocycle units. In both compounds, the 2D anionic layers are linked by sodium ions in various manners to generate quite different 3D architectures. Compounds 1 and 2 exhibit violet photoluminescences in the solid state. In addition, IR spectra, powder X-ray diffraction, elemental analysis, and thermogravimetric analysis of compounds 1 and 2 are also investigated.

The reactions of Ln(NO3)3 with 2,5-dihydroxy-1,4-benzenedicarboxylic acid (H2-DHBDC) under solvothermal conditions produce a series of isomorphous lanthanide coordination polymers with the empirical formula {[Ln2(DHBDC)3(DMF)4](DMF)2}n (Ln = La(1), Nd(2), Sm(3), Gd(4), and Er(5)). Compound {[Ln2(DHBDC)3(DMF)4](DMF)2}n contains dinuclear Ln2(COO)6 units, which are linked by the –C6H2(OH)2– spacers to form a three-dimensional framework exhibiting α-Po topology (pcu-(412·63) net) based on dinuclear Ln2(COO)6 nodes. The three-dimensional framework shows one-dimensional open channels that accommodate the coordinated and guest DMF molecules. Gas adsorption measurements on compound 4 indicate that the desolvated solid of 4 adsorbs CO2 and shows nonporous behavior toward N2. The adsorption favoring CO2 over N2 may arise from the chemical environments of the host framework, which contains the polar –OH groups of the phenyl and the π-electrons of the ligands. Magnetic measurements on compound 4 indicate that there is an antiferromagnetic interaction between Gd3+ ions.

In the title compound, C12H12ClN5O3S, the pyrazole ring and the benzene ring are approximately coplanar. The mean plane of the pyrazole ring makes a dihedral angle of 12.82 (13)° with the mean plane of the benzene ring. The crystal packing is stabilized by intra­molecular N—H⋯O and inter­molecular N—H⋯O and N—H⋯N hydrogen bonds.