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Good quality single crystal of Tm3+ doped YPO4 crystal with an astounding emission cross-section was grown utilizing the flux method and the KF–P2O5 flux was employed for the first time to grow YPO4 crystal.

Racemate (rac-1) and conglomerate (cong-1) crystals show different phosphorescence behaviour. Rac-1 is a strong excitation-wavelength-tunable photoluminescent material; cong-1 exhibits white-light emission upon temperature change with a CIE 1931 coordinate of (0.33, 0.31).

The synergistic catalytic effect of arylboron and β-ketoenamine double acceptors in the novel arylboron functional COF improves the efficiency of photocatalytic hydrogen evolution.

High-quality crystals of Sm:GdCa4O(BO3)3 were grown by the Czochralski method. The crystal structure and the optical and thermal properties were determined.

Long non-coding RNAs (lncRNAs) have been reported to exert critical functions in the malignant development of many cancers. lncRNA HLA complex group 18 (HCG18) has been confirmed to have a promoting effect on various cancers. However, whether HCG18 functions in PC is still unclear. Therefore, the current study aimed at unveiling the role of HCG18 in PC progression and its regulatory mechanism on the biological behaviors of PC. Here, RT-qPCR was utilized to detect HCG18 expression, and then, functional experiments were conducted to verify the effects of HCG18 on PC cell proliferation, migration, invasion, and apoptosis. According to the results, HCG18 was significantly up-regulated in PC cells and it facilitated cell proliferation, migration, and invasion in PC. Furthermore, a series of mechanism experiments were carried out to verify the relationship among HCG18, miR-370-3p, and DEAD-box helicase 3 X-linked(DDX3X) in PC cells. Final rescue assays showed that DDX3X overexpression could reverse the inhibitory function of silencing HCG18 on PC progression. In summary, our study showed that lncRNA HCG18 accelerated cell proliferation, invasion, and migration of PC via up-regulating DDX3X through sponging miR-370-3p, providing a novel finding about PC-related regulatory mechanism.

The synthesis of highly stereoregular poly(mandelic acid) (PMA) via controllable polymerization is a considerable challenge because of the easy racemization of monomers during polymerization; conse...

Large size HoCa4O(BO3)3 (HoCOB) crystal was successfully grown by the Czochralski (Cz) method. Through single-crystal X-ray diffraction the cell parameters were determined to be a = 8.090(3) A, b = 16.018(7) A, c = 3.5317(14) A, β = 101.28°(4) and Z = 2 with the space group Cm. The Archimedes method was used to measure the density which was 3.85 g cm−3. In the transmittance spectrum of HoCOB, there are strong absorption peaks from 200 to 680 nm and 1800 to 2200 nm, corresponding to the Stokes levels between 13 219 and 49 335 cm−1. The thermal and the piezoelectric properties were investigated under different temperatures. At 300 K around, the thermal expansion coefficient, thermal conductivity, specific heat, and relative dielectric constant on the b axis direction (i.e. the unique two-fold axis direction) were 5.35 × 10−6 K−1, 2.18 W m−1 K−1, 0.58 g−1 K−1, and 12.5, respectively.

The class of radical polymers is one of the most appealing electrode materials in organic radical batteries (ORBs). Herein, we report a series of copolymers poly(2,2,6,6-tetramethylpiperidinyloxyl-...

Monomer sequence controllable syntheses of copolymers, including copolyesters, remain a challenge in polymer science. Although alternating sequence-controlled copolymerization of O-carboxyanhydride...

The development of cisplatin resistance often results in cisplatin inefficacy in advanced or recurrent bladder cancer. However, effective treatment strategies for cisplatin resistance have not been well established.Gene expression was measured by qRT-PCR and Western blotting. CCK-8 assay was performed to detect cell survival. The number of apoptotic cells was determined using the Annexin V-PI double-staining assay. The level of reactive oxygen species (ROS) was measured using 2',7'-dichlorodihydrofluorescein diacetate fluorescent dye, and the ATP level was detected using an ATP measurement kit.The expression of receptor-interacting protein kinase 1 (RIPK1), a key regulator of necroptosis, gradually decreased during cisplatin resistance. We first used piperlongumine (PL) in combination with cisplatin to act on cisplatin-resistant BC cells and found that PL-induced activation of RIPK1 increased the sensitivity of T24 resistant cells to cisplatin treatment. Furthermore, we revealed that PL killed T24 cisplatin-resistant cells by triggering necroptosis, because cell death could be rescued by the mixed lineage kinase domain-like (MLKL) protein inhibitor necrotic sulfonamide or MLKL siRNA, but could not be suppressed by the apoptosis inhibitor z-VAD. We further explored the specific mechanism and found that PL activated RIPK1 to induce necroptosis in cisplatin-resistant cells by stimulating mitochondrial fission to produce excessive ROS.Our results demonstrated the role of RIPK1 in cisplatin-resistant cells and the sensitization effect of the natural drug PL on bladder cancer. These may provide a new treatment strategy for overcoming cisplatin resistance in bladder cancer.

Catalytic alkylation of stable alkenyl C-O electrophiles is synthetically appealing, but studies to date have typically focused on the reactions with alkyl Grignard reagents. We here report a cross-electrophile reaction of alkenyl acetates with alkyl bromides. This work has enabled a new method for the synthesis of aliphatic alkenes from alkenyl acetates to be established that can be used to add more structural complexity and molecular diversity with enhanced functionality tolerance. The method allows for a gram-scale reaction and modification of biologically active molecules, and it affords access to useful building blocks. Preliminary mechanistic studies reveal that the Ni(I) species plays an essential role for the success of the coupling of these two reactivity-mismatched electrophiles.

Ring-opening polymerization (ROP) of rac-O-carboxyanhydride of mandelic acid (rac-manOCA) is a promising method to synthesize isotactic biodegradable polyester of poly(mandelic acid), which has a h...

Two new zincoborates, namely, Pb3Ba3Zn6(BO3)8 and α-BaZn2(BO3)2, were synthesized by the high-temperature solution method and their structures were determined by single-crystal X-ray diffraction for the first time. The structure of Pb3Ba3Zn6(BO3)8 can be described as a three-dimensional framework consisting of [Zn4B2O15]∞ chains and isolated ZnO4 tetrahedra and BO3 triangles, which contains three different types of tunnels with Pb2+ and Ba2+ cations residing among them. α-BaZn2(BO3)2 exhibits a two-dimensional layered structure with a [Zn2B2O6] layer, which is formed by [ZnBO4] chains and [Zn2B2O8] chains. Interestingly, both Pb3Ba3Zn6(BO3)8 and α-BaZn2(BO3)2 both contain two different dimensional Zn–O configurations in their structures, which has not been found in other zincoborates. In addition, thermal property analysis, and UV-vis-NIR diffuse reflectance and infrared spectroscopy were also performed. First-principles theoretical studies were also conducted to aid the understanding of their band structures and densities of states.

To control the monomer sequence in copolymers of different hydroxyl acids remains a big challenge so far, which is valuable for tuning the properties of copolyesters. In this work, the perfectly al...

The single-stage photovoltaic grid connected inverter needs to realize maximum power point tracking (MPPT) and inverter functions at the same time. The nonlinear and strong coupling characteristics of the system make the control very complex. The conventional control method is easy to lead to poor stability of the system, DC bus voltage collapse and other problems. To solve the above problems, a design scheme of seeker-optimization-algorithm (SOA) optimization back-stepping (BS) control is proposed. Firstly, the mathematical model of three-phase grid connected inverter system with decoupling active and reactive power is established in $\alpha {-} \beta$ static coordinate system, and then the BS controller of inverter is designed. Then the SOA is used to identify and optimize the shortcomings of BS control in MPPT. The stability of the controller is proved by Liyapunov stability theory. The results show that the scheme can achieve the maximum power tracking and grid connected function well, and has good stability and robustness.

Poor charge separation is the main factor that limits the photocatalytic hydrogen generation efficiency of organic conjugated polymers. In this work, a series of linear donor–acceptor (D–A) type oligomers are synthesized by a palladium-catalyzed Sonogashira–Hagihara coupling of electron-deficient diborane unit and different dihalide substitution sulfur functionalized monomers. Such diborane-based A unit exerts great impact on the resulting oligomers, including distinct semiconductor characters with isolated lowest unoccupied molecular orbital (LUMO) orbits locating in diborane-containing fragment, and elevated LUMO level higher than water reduction potential. Relative to A-A type counterpart, the enhanced dipole polarization effect in D–A oligomers facilitates separation of photogenerated charge carriers, as evidenced by notably prolonged electron lifetime. Owing to π–π stacking of rigid backbone, the oligomers can aggregate into an interesting 2D semicrystalline nanosheet (≈2.74 nm), which is rarely reported in linear polymeric photocatalysts prepared by similar carbon–carbon coupling reaction. Despite low surface area (30.3 m2 g−1), such ultrathin nanosheet D–A oligomer offers outstanding visible light (λ > 420 nm) hydrogen evolution rate of 833 µmol g−1 h−1, 14 times greater than its A-A analogue (61 µmol g−1 h−1). The study highlights the great potential of using boron element to construct D–A type oligomers for efficient photocatalytic hydrogen generation. © 2021 Wiley-VCH GmbH

Synthesizing different types of sequence-controlled copolyesters can enrich the diversity of copolyesters and modify their properties more precisely, but it is still a challenge to synthesize a complicated sequence-controlled copolyester using different hydroxy acids in a living polymerization manner. In this work, a highly regioselective and stereoselective catalytic system was developed to synthesize biorenewable and biodegradable copolyesters of mandelic acid and lactic acid with isotactic-alternating, heterotactic-alternating, and ABAA-type precise and complicated sequences. Because of the regular incorporation of mandelic acid into polylactide, these sequence-controlled copolymers of mandelic acid and lactic acid show higher glass-transition temperatures than polylactide and a random copolymer. A stereocomplexation interaction between two opposite enantiomeric isotactic polymer chains was also discovered in the isotactic-alternating copolymer.

A novel low frequency AC-AC SPWM modulated frequency converter is implemented based on Microcontroller chip. The control function performed by the Microcontroller chip AT89C51 is twofold: firstly, to achieve frequency conversion by changing number N of half wave, between two natural commutation points. Secondly, to obtain voltage regulation by changing the duty-cycle of PWM pulse (high frequency) in the half wave of grid power passing through. As a result, the Microcontroller-based direct AC-AC converter can achieve voltage regulation and frequency conversion at the same time, which is suitable for motor of flexible low-frequency speed regulation. The Microcontroller-based control algorithm and the implementation are presented in detail and the design is verified by both simulation and experimental testing results.

Two sodium/potassium tetradentate aminobisphenolate ion-paired complexes were synthesized and structurally characterized. These ion-paired complexes are efficient catalysts for the ring-opening polymerization of rac-lactide (rac-LA) in the presence of 5 equivalents BnOH as an initiator and the side reaction of epimerization can be suppressed well at low temperatures. The polymerizations are controllable, affording polylactides with desirable molecular weights and narrow molecular weight distributions; the highest molecular weight can reach 50.1 kg mol-1 in this system, and a best isoselectivity of Pm =0.82 was achieved. Such polymerizations have rarely been reported for isoselective sodium/potassium complexes without crown ether as an auxiliary ligand. The solid structures suggest that BnOH can be activated by an interaction with the anion of sodium/potassium complex via a hydrogen bond and that the monomer is activated by coordination to sodium/potassium ion.

Organic compounds are appealing electrode materials for potassium-ion batteries (PIBs) owing to their economical and eco-friendly nature. Here, we report an important organic semiconductor, 3,4,9,10-perylenetetracarboxylic diimide (PTCDI), as a high-rate anode for PIBs. The PTCDI electrode is found to deliver a high average specific capacity of 310 mA h g−1 at 0.5 A g−1 and a remarkable rate performance (in the range from 0.5 to 5.0 A g−1), which can be attributed to the fast K ion diffusion (up to ∼10−8 cm2 s−1) and low charge-transfer resistance (93 ohm). The proposed six-electron storage mechanism for the PTCDI electrode during the discharge/charge process has been revealed by ex situ infrared (IR) spectroscopy and ex situ X-ray diffraction (XRD), as well as density functional theory (DFT) calculations. This study could pave the way for developing advanced PIB anodes with low cost and high performance.

Tubular hematite with high-concentration, uniform doping is regarded as a promising material for photoelectrochemical water oxidation. However, the high-temperature annealing commonly used for activating doped hematite inevitably causes deformation of the tubular structure and an increase in the trap states. In the present work, Sn-doped tubular hematite on fluorine-doped tin oxide (FTO) is successfully obtained at 750 °C from a Sn-coated FeOOH tube precursor. Sn/P codoping, which is rarely considered for hematite, is also achieved via a gas phase reaction in phosphide atmosphere. The tubular morphology allows the dopant to diffuse from both the inner and outer surfaces, thus decreasing the doping profile in the radial direction. The even distribution of Sn and P synergetically increases the carrier density of hematite by one order of magnitude, which shortens the width of the depletion layer to ca. 2.3 nm (compared with 19.3 nm for the pristine sample) and leads to prolonged carrier lifetime and efficient charge separation. In addition, this codoping protocol does not introduce additional surface trap states, as evidenced by the increased charge injection efficiency and surface kinetic analysis using intensity modulated photocurrent spectroscopy (IMPS). As a result, the morphology- and doping-engineered hematite exhibits photocurrents of 0.9 mA cm-2 at 1.23 V and 3.8 mA cm-2 at 2.0 V vs. RHE under AM 1.5 G illumination (100 mW cm-2) in 1.0 M NaOH, representing 4.5-fold and 4.8-fold enhancements, respectively, compared with the photocurrents of undoped hematite. The present method is shown to be effective for preparing multi-element-doped hematite nanotubes and may find broad application in the development of other nanotubular photoelectrodes with or without doping for efficient and robust water oxidation.

Exploring the moisture-insensitive catalysis system for the ring-opening polymerization of cyclic esters is very valuable for the synthesis of polyesters in industry. To reduce metal residue in final polymers, using ppm-level catalysts for the moisture-insensitive and controllable ROP system is still a big challenge until now. In this work, as a general strategy, a series of D3 symmetrical binuclear yttrium phenoxides were applied in the moisture-insensitive ring-opening polymerization of rac-lactide. The structures of these yttrium complexes can be reversibly switched between highly active and less active species in the presence of water via changing temperature. These catalysts are so robust in air, the loading of catalyst can be as low as 15 ppm, and one molecular catalyst can mediate the synthesis of more than 1000 polymer chains. The low initiation efficiency of water was proved unambiguously; hence, the polymerizations are controllable with a highly efficient initiator of alcohol in moisture conditi...

By the application of cation substitution, five new members of cyclophosphates, RbCdP3O9, CsPbP3O9, CsSrP3O9, RbMgP3O9, and RbCaP3O9, were obtained by a high-temperature melt method and structurally analyzed. The five compounds have identical stoichiometries, and all of them feature a three-dimensional network, which consists of MIIO6 (MII = Cd, Mg, Ca, Pb, Sr) octahedra and cyclic P3O9 units, while alkali-metal atoms are located within the network. However, RbCdP3O9 and CsPbP3O9 belong to the asymmetric space groups P6 c2 and Pna21, respectively, and the other three compounds belong to orthorhombic space group Pnma. Detailed structure comparisons in the MI-MII-P-O and (MIMIIP3O9) n ( n = 1, 2, 6) systems are discussed. Remarkably, KMgP3O9 as one of the cyclophosphate members exhibits a second harmonic generation (SHG) intensity about 0.2 times that of KH2PO4 (KDP), RbCdP3O9, and CsPbP3O9 also show SHG responses 0.1 times that of KDP. In addition, the related optical properties are discussed. Furthermore, theoretical calculations and dipole moments were calculated to explain the relation of structure and optical properties.

A series of alkali metal complexes with 2,2′-ethylidenebis(4,6-di-tert-butylphenol) (EDBP-H2) as a ligand have been synthesized. In the presence of benzyl alcohol as an initiator, all complexes exhibit good catalytic behaviors for the ring-opening polymerization (ROP) of rac-lactide, giving desirable molecular weights and narrow molecular weight distributions. The relative order of activities for this series of complexes is Li > Na > K > Rb, which is related to metallic ion radius; and Lewis acidity of these metal ions is also an important factor for the kinetics of the ROP. The relative order of stereoselectivities for this series of complexes is Rb ≈ K > Na ≫ Li in this system. The first example of Rb complex in the ROP of rac-lactide in this paper was also described, showing a modest activity and a nice polymerization control, even with a certain isoselectivity.

Field-effect transistor (FET)-based microelectronics is approaching its size limit due to unacceptable power dissipation and short-channel effects. Molecular quantum dot cellular automata (MQCA) is a promising transistorless paradigm that encodes binary information with bistable charge configurations instead of currents and voltages. However, it still remains a challenge to find appropriate candidate molecules for MQCA operation. Inspired by recent progress in boron radical chemistry, we theoretically predicted a series of new MQCA candidates built from diboryl monoradical anions. The unpaired electron resides mainly on one boron center and can be shifted to the other by an electrostatic stimulus, forming bistable charge configurations required by MQCA. By investigating various bridge units with different substitutions (ortho-, meta-, and para-), we suggested several candidate molecules that have potential MQCA applications.

Three Pb5Zn4B6O18 polymorphs were synthesized by a high temperature solution method. Their structures were determined using single crystal X-ray diffraction and they crystallize in P21/c for α-, γ-Pb5Zn4B6O18 and P for β-Pb5Zn4B6O18. It is interesting that α- and β-Pb5Zn4B6O18 crystallize in different space groups with similar structures and α- and γ-Pb5Zn4B6O18 crystallize in the same space group with totally different structures. In α- and β-Pb5Zn4B6O18, ZnO4 tetrahedra connect with isolated BO3 triangles to construct two dimensional (2D) layers, while in γ-Pb5Zn4B6O18, 2D Zn–B–O layers change to the 3D framework. The phase transformations of Pb5Zn4B6O18 are investigated by the combination of powder X-ray diffraction, thermal behavior analysis and theoretical simulation. Additional functional properties have been investigated using methods such as including UV-vis-NIR diffuse reflectance and IR spectroscopy.

A method of rapidly differentiating lung tumor from healthy tissue is extraordinarily needed for both the diagnosis and the intraoperative margin assessment. We assessed the ability of fluorescence lifetime imaging microscopy (FLIM) for differentiating human lung cancer and normal tissues with the autofluorescence, and also elucidated the mechanism in tissue studies and cell studies. A 15-patient testing group was used to compare FLIM results with traditional histopathology diagnosis. Based on the endogenous fluorescence lifetimes of the testing group, a criterion line was proposed to distinguish normal and cancerous tissues. Then by blinded examined 41 sections from the validation group of other 16 patients, the sensitivity and specificity of FLIM were determined. The cellular metabolism was studied with specific perturbations of oxidative phosphorylation and glycolysis in cell studies. The fluorescence lifetime of cancerous lung tissues is consistently lower than normal tissues, and this is due to the both decrease of reduced nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD) lifetimes. A criterion line of lifetime at 1920 ps can be given for differentiating human lung cancer and normal tissues.The sensitivity and specificity of FLIM for lung cancer diagnosis were determined as 92.9% and 92.3%. These findings suggest that NADH and FAD can be used to rapidly diagnose lung cancer. FLIM is a rapid, accurate and highly sensitive technique in the judgment during lung cancer surgery and it can be potential in earlier cancer detection.

The stereoselective ring-opening polymerization (ROP) of O-carboxyanhydrides (OCAs) remains a major challenge due to the easy epimerization of monomers. In this work, using a zinc alkoxide initiator, highly efficient ROP of enantiopure 5-methyl-1,3-dioxolane-2,4-dione (LacOCA), 5-benzyl-1,3-dioxolane-2,4-dione (PheOCA), and 5-(4-(benzyloxy)benzyl)-1,3-dioxolane-2,4-dione (Try(Bn)OCA) was achieved without obvious epimerization. Moreover, highly isoselective ROP of rac-LacOCA, rac-PheOCA, and rac-Try(Bn)OCA was successful with the highest isoselectivity of Pm = 0.97 at −70 °C.

In Inertial Confinement Fusion (ICF) program, the third harmonic generation crystal (DKDP), known as the tripler, is the the most easily damaged in the whole optical chain [1]. One main reason for this phenomenon is the absorption of UV light increasing nonlinearly with laser radiation intensity [2]. Although the nonlinear optical properties of the KDP crystal has been investigated at the wavelengths of 211, 216, 248, 264, 266, and 355 nm, the properties of the DKDP crystal has been seldom explored. In this paper, in order to explore how the nonlinear absorption and refraction affect the laser-induced damage (LID) of DKDP crystal, the Z-scan technique was employed to measure the third-order optical nonlinearity of 70% deuterated DKDP crystals annealed under different temperatures at the wavelength of 355 nm by a picosecond laser [3].