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Stimuli-responsive polymer gels have recently attracted great attention due to their heat/solvent resistance, dimensional stability, and unique sensitivity to external stimuli. In this work, we synthesized thiol-functionalized tetraphenylethylene (TPE) and constructed polymer gels through thiol-ene click reaction. The synthetic process of the polymer gels could be monitored by fluorescence emission of TPE moieties based on aggregation-induced emission mechanism. In addition, due to the dual redoxand acid responsiveness of the polymer gels, in the presence of dithiothreitol and trifluoroacetic acid, fluorescence quenching of the polymer gels can be observed. This stimuli-responsive characteristics endows the polymer gels with potential applications in fluorescent sensing and imaging, cancer diagnosis and selfhealing materials.

Background Tuberculosis (TB) is a widespread infectious disease, with an incidence that is increasing worldwide. Cutaneous TB (CTB) occurs rarely, accounting for less than 1% of all TB cases. Due to the clinical presentation and diagnostic difficulties, CTB is often clinically neglected and misdiagnosed. Case summary A 32-year-old man underwent several debridement surgeries and skin flap transplantation after trauma. The wound remained unhealed, accompanied by sinus formation. According to empirical judgment, T-cell spot of TB test, and bacterial culture of pyogenic fluids, he was diagnosed with CTB due to infection with exogenous Mycobacterium tuberculosis. A comprehensive anti-TB regimen that included isoniazid, rifampicin, ethambutol, and pyrazinamide was applied. The sinus was filled with a hydrophilic fiber-containing silver dressing, and wound-protecting sponges were applied to part of the wound. The wound healed after 40 d. No ulceration was found within 2 mo after discharge; further follow-up will be conducted. Conclusion A non-healing wound may be caused by TB infection. Comprehensive treatment of CTB is effective.

In this study, a direct Z-scheme AgBr/α-Ag2WO4 heterojunction was prepared via in situ anion exchange at room temperature. The construction strategy is energy- and time-saving for large scale syntheses. The α-Ag2WO4 cluster was tightly anchored by converted AgBr nanoparticles of small size in the range of 5–15 nm to induce an effective interfacial effect. The visible light photoactivity of the optimal sample AgBr/α-Ag2WO4-20% is drastically boosted by 53.4- and 26.4-fold towards the degradation of Rhodamine B (RhB) and phenol, respectively. Under the exposure of simulated sunlight, the photocatalytic degradation rate of RhB is also enhanced as high as 12.4 times compared with bare α-Ag2WO4. Besides the enhanced light harvesting, the improved photoactivity is mainly ascribed to the accelerated spatial separation of photoexcited carriers as evidenced by PL and photoelectrochemical analyses. Based on the energy band structure and reactive oxidation species, a solid Z-scheme heterojunction mechanism at the AgBr/α-Ag2WO4 interface is proposed and discussed. The study offers some insight into the design of hetero-photocatalysts containing the same cation with improved photocatalytic behavior in energy and environmental applications.

The aerobic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA), a promising renewable monomer to produce bio-based polymers such as polyethylene furanoate (PEF), has recently emerged as the subject of increasing interest. Here, holey 2 D Mn2 O3 nanoflakes were obtained by a facile thermal treatment of a Mn-based metal-organic framework (MOF) precursor. The structural and morphological properties of the nanoflakes were characterized by powder XRD, FTIR, SEM and TEM to explore the formation process. It was inferred that the linker loss in the MOF precursor and the oxidation of the Mn cation induced by the heat-treatment in air were responsible for the formation of holey 2 D Mn2 O3 nanoflakes. The specific morphology and redox cycle of the Mn cation on the surface endowed the synthesized nanoflakes with promising performance on the selective oxidation. The obtained nanoflakes calcined at 400 °C (M400) afforded over 99.5 % yield of FDCA at complete conversion of HMF, which is superior to the catalytic activity of commercial Mn2 O3 and activated MnO2 . To our knowledge, Mn2 O3 exhibiting such a high performance on the aerobic oxidation of HMF to FDCA has not yet been reported. Based on the investigation of the experimental parameters, a plausible reaction mechanism was proposed.

BackgroundMalnutrition is highly prevalent in critically ill children in the pediatric intensive care unit .We aimed to investigate the efficiency of bioelectrical impedance analysis (BIA) measurements and phase angle (PhA) analysis for the assessment of nutritional risk and clinical outcomes in critically ill children.MethodsThis single-center observational study included patients admitted to the Pediatric Intensive Care Unit (PICU) of Chengdu Women’s and Children’s Central Hospital. All patients underwent anthropometric measurement in the first 24 h of admission and underwent BIA measurements within 3 days after the admission. The patients were classified into different groups based on body mass index (BMI) for age. Electronic hospital medical records were reviewed to collect clinical data for each patient. All the obtained data were analyzed by the statistics method.ResultsThere were 204 patients enrolled in our study, of which 32.4% were diagnosed with malnutrition. We found that BMI, arm muscle circumference, fat mass, and %body fat were lower in the group with poorer nutritional status (P P P

Background: Glucose variability (GV) is one of the common complications in critically ill patients, and studies investigating the role of GV in the prognosis of pediatric patients are scarce in China. And there is no consensus on the measurement of GV. Thus, this study took a prospective, multi-center cohort observational study to identify the ‘best’ index of variability in non-diabetic critically ill children and to confirm whether GV is associated with unfavorable outcomes and whether this association persists after control of hypoglycemia and hyperglycemia. Materials and Methods: Four GV indices were chosen and calculated in our study, namely, mean absolute glucose (MAG), standard deviation (SD), glycemic lability index (GLI), and another metric-average consecutive absolute change percentage (ACACP), which can be used in the real-time clinical decision. The primary outcome was 28-day mortality. Multivariate Cox regression analysis was used to identify the potential predictors for the outcome. And the area under the curve (AUC), net reclassification improvement (NRI), and integrated discrimination improvement (IDI) were calculated to assess the predictability of dysglycemia (glucose variability and hypo/hyperglycemia) on the unfavorable outcome. Results: Of the total of 780 participants, 12.4% (n=97) died within 28 days after PICU admission. There were statistical differences in terms of four GV indices (SD, GLI, MAG, and ACACP) between survivors and non-survivors, in which MAG obtained the largest area under the curve and showed a strong connection to ICU mortality independently. Subsequent addition of MAG to the multivariate Cox model for hyperglycemia resulted in further quantitative evolution of the model statistics (AUC 0.651 to 0.681, P=0.001; IDI: 0.017, P=0.044; NRI:0.224, P=0.186). And the impact of hyperglycemia (adjusted HR1.419, 95% CI 0.815-2.471, p=0.216) on outcome was attenuated and no longer statistically relevant after adjustment for MAG (adjusted HR 2.455, 95%CI 1.411-4.270, p=0.001). Conclusions: GV is closely associated with unfavorable outcomes, and may be a more powerful negative predictor of outcome than hypoglycemia and hyperglycemia. These findings emphasize the crucial role of GV in PICU children. GV index that contains information such as time, rate of change, etc. is the focus of future research. MAG may be a good choice. Trial registration: Chinese clinical registration (ChiCTR), ChiCTR2000030846. Registered 15 March 2020, https://www.chictr.org.cn/showproj.aspx?proj=50760.

A series of 3d-4f heterometallic coordination polymers (CPs), namely, Ln2(CuL)2(nipt)3(H2O)]⋅nH2O (Ln = Sm 1, Nd 2, Gd 3, for 1–2 n = 2, for 3 n = 1.6), [Yb2(CuL)4(nipt)3]·3.5H2O (4), [Pr2(NiL)(nipt)3(H2O)]⋅1.5H2O (5), [Sm2(NiL)(nipt)3(H2O)2]CH3OH⋅H2O (6), [Er2(NiL)2(nipt)3(H2O)2]⋅3H2O (7) (ML, H2L = 2, 3-dioxo-5, 6, 14, 15-dibenzo-1, 4, 8, 12-tetraazacyclo-pentadeca-7, 13-dien; H2nipt = 5-nitroisophthalic acid) were obtained by a solvothermal method and structurally characterized. Complexes 1–3 have 3,3,4,5-connected (3.4.5)(32.42.5.63.72)(42.63.8)(42.6) topological structure consisting of two different chains. 4 exhibits a two-dimensional (2D) heterometallic structure with 3-connected (63) topology. 5 displays a 2D framework formed by four-strand meso-helical chains and characterized by 6,6,4,4,4-connected (411.64)(412.63)(43.62.8)(45.6)2 topology. Compound 6 has 3,4,4,3-connected (43)(44.62)(42.124)(42.6) topological structure formed by three-strand meso-helical chains. In 7, two kinds of μ3-bridged nipt2− ligands together with NiL connect the eight-coordinated Er3+ ions to form a 2D structure, and the 2D layers are extended by μ2-bridged nipt2− into a three-dimensional (3D) microporous framework with 4,4,3,3-connected (4.62.83)2(4.82)2 topology. Interestingly, for 1, 2 and 4, CuL-sensitized the near-infrared emissions form Sm(III), Nd(III) and Yb(III) were firstly found under visible light irradiation. Moreover, the magnetic properties of 1, 2, 4 and 5 are also discussed.

Catalysis of C1 chemistry, especially for carbon monoxide (CO), carbon dioxide (CO2) and methane (CH4), is critically important for the clean production of fuels and chemicals and future energy sustainability. However, due to the relatively inert nature and low reactivity of these C1 molecules, their activation and transformation into clean fuels and high value-added chemicals still remain formidable challenges. In this context, metal-organic frameworks (MOFs), as relatively new emerging crystalline porous materials, have been shown to be promising heterogeneous catalysts or supports/precursors in the design and synthesis of various functional nanomaterials for addressing these challenges. In this review, the recent advances in MOF-based heterogeneous catalysts for transforming CO, CO2 and CH4 into high value-added chemicals are systematically reviewed. Emphasis is mainly placed on the catalytic reactivity, reaction mechanism and catalyst design. Additionally, major challenges and opportunities for MOF catalysts in the conversion of C1 chemistry are discussed to outline aspects for further development in this ongoing research field. It is anticipated that this review will provide a useful guide to chemists and material scientists attempting to design better MOF-based catalysts for the chemical conversion of C1 compounds.

The work presents a combinative merit of non-metal ion doping and active facet effect of Bi2O2CO3 photocatalyst. Br-doped Bi2O2CO3 nanosheets with exposed {0 0 1} facets were facilely prepared via a one-step hydrothermal reaction with the assistance of cetyltrimethylammonium bromide (CTAB) at a mild temperature of 60 °C for 4 h. The presence of CTAB not only influences the growth of Bi2O2CO3 crystalline but also leads to a Br-doping. Based on the crystal structure and DFT calculation, bromine from CTAB as dopant interstitially incorporates into Bi2O2CO3 lattice, which alters the band gap positions of Bi2O2CO3 and generates delocalized impurity states at the Fermi level. The improved electronic structure endows Br-doped Bi2O2CO3 with a broadened light-harvesting and accelarated charge migration. In addition, the thin nanosheet means more exposure of {0 0 1} active facets and larger internal electric field, which would also benefit for the charge separation. The sample with a trace Br content of 1.17 wt% shows the best degradation efficiency for RhB with a rate constant k enhanced by 3.6 folds compared with that of pure Bi2O2CO3 under simulated solar irradiation. Combining the effective catalytic sites and the detected active species, a possible migration mechanism of photogenerated e−/h+ pairs on the surface of Br-doped Bi2O2CO3 nanosheet is proposed. The work provides some new insights into the rational design and synthesis of non-metal doped semiconductor photocatalyst with facet dependency.

α-Ag2WO4 clusters comprising an assembly of nanorods were controllably fabricated via a simple ion exchange method at room temperature. The phase, morphology, microstructure, optical absorption, photoluminescence, photoelectrochemical properties and photocatalytic behavior of the products were systematically explored. α-Ag2WO4 nanorod-clusters of high purity are achieved at a medium pH of 9.8 provided by adjusting the molar ratio of AgNO3 and Na2WO4 to 1 : 4, and the sample exhibits superior photocatalytic activity for the degradation of organic pollutants. Its rate constant k is as high as 21.8 fold in comparison with that of the sample obtained with stoichiometric raw materials at a ratio of 1 : 0.5. The boosted photoactivity of α-Ag2WO4 clusters can be well accounted for by the broadened light harvesting and accelerated charge separation, which are proved by the red-shifted light absorption, higher photocurrent and a smaller Nyquist impedance radius. Based on the detected active species and the band edge positions, a possible migration mechanism of photoinduced e−/h+ pairs on the surface of α-Ag2WO4 clusters was proposed. This work provides some new insights into the rational design and synthesis of photocatalysts with a deep understanding of the relationship among the experimental parameters, the microstructure and properties to acquire a more desired photoactivity.

Prussian Blue Analogues Mn3[Fe(CN)6]2·12H2O porous nanoparticles have been achieved by coprecipitation method and using polyvinyl pyrrolidone (PVP) as a protective matrix. The obtained nanoparticles were characterized by X-ray diffraction (XRD), infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TG), scanning electron microscopy (SEM), and high resolution transmission electron microscopy (HRTEM). The X-ray diffraction measurement results show that all the obtained nanoparticles are face centered cubic structure. The infrared spectroscopy (IR) and X-ray photoelectron spectroscopy (XPS) measurement results indicate that Mn3[Fe(CN)6]2·12H2O nanoparticles are mixed-valence, and the ratios of MnIIFeIII to MnIIIFeII in obtained nanoparticles are different in water and water-methanol mixed solvent. The magnetic studies of nanocubes (about 480 nm, coming from water synthesis) and nanospheres (about 200 nm, from co-solvent synthesis) materials show that both samples have spin-glass behavior, but magnetic property measurement results indicated Tc, Tb and Tg temperatures of Mn3[Fe(CN)6]2·12H2O decreases as the size of nanoparticle reduces.

Based on first-principles calculations using density functional theory, this paper systematically studies the effects of uniaxial tension-compression deformation on the stability and electrical and thermal properties of monolayer graphene and AA stacked bilayer graphene. The study shows that the original symmetry of graphene is broken by the tensile and compression deformations, catalyzing the interlayer coupling of bilayer graphene. Its electronic energy band, phonon dispersion, and other physical properties have changed. The transition from metalloid to semiconductor has completed since the deformation weakens the stability of the graphene system to varying degrees and opens the band gap of monolayer graphene. The band gap becomes larger with the increase of tensile and compressive deformation, in which way it can be adjusted. Influenced by the tiny tensile deformation, metalloid properties are exhibited by a small band gap of intrinsic AA-stacked bilayer graphene, and then the band gap becomes larger as the deformation increases. A band gap appears in the system phonon dispersion curves when the compression deformation increases to -15%. The phonon mode softens and shows virtual frequency. The value of virtual frequency increases with the increase of compression deformation. At the very moment, the vibration mode is discontinuous, and the system is unstable.

The effect of bend angle on the stability, electronic structure and optical properties of S absorbed graphene system is studied by using density functional theory based on the first - principles. Within the scope of the current study, it is found that the C atoms which are closest to the S atom are pulled up, the graphene plane is distorted, and the band gap of the graphene is opened, which changes graphene from quasi-metal to semiconductors. Bending deformation decreases the structural stability of S atom adsorbed on graphene system. The adsorption energy decreases with the increase of bending angle. After the intrinsic graphene is bent, the band gap is opened, and the bandgap increases with the bending angle. When the bending angle is between 0°–20°, it still corresponds to the quasi-metal property. When the bending angle increases to 25°, it gradually changes from small bandgap semiconductor to medium bandgap semiconductor. The band gap of graphene adsorbed S atom system decreases with the increase of the bending angle, and it always corresponds to medium bandgap semiconductors. When the angle is increased to 30°, the system loses its stability. The rate of increase of absorption coefficient increases with the increase of bending angle. The deformation causes the maximum absorption peak and the maximum reflection peak of the system to red shift, and the degree of red shift increases with the increase of the bending angle.

MicroRNAs (miRNAs) are endogenous non-protein-coding small RNAs that play crucial and versatile regulatory roles in plants. Using a computational identification method, we identified 55 conserved miRNAs in tea (Camellia sinensis) by aligning miRNA sequences of different plant species with the transcriptome library of tea strain 1005. We then used quantitative real-time PCR (qRT-PCR) to analyze the expression of 31 identified miRNAs in tea leaves of different ages, thereby verifying the existence of these miRNAs and confirming the reliability of the computational identification method. We predicted which miRNAs were involved in catechin synthesis using psRNAtarget Software based on conserved miRNAs and catechin synthesis pathway-related genes. Then, we used RNA ligase-mediated rapid amplification of cDNA ends (RLM-RACE) to obtain seven miRNAs cleaving eight catechin synthesis pathway-related genes including chalcone synthase (CHS), chalcone isomerase (CHI), dihydroflavonol 4-reductase (DFR), anthocyanidin reductase (ANR), leucoanthocyanidin reductase (LAR), and flavanone 3-hydroxylase (F3H). An expression analysis of miRNAs and target genes revealed that miR529d and miR156g-3p were negatively correlated with their targets CHI and F3H, respectively. The expression of other miRNAs was not significantly related to their target genes in the catechin synthesis pathway. The RLM-RACE results suggest that catechin synthesis is regulated by miRNAs that can cleave genes involved in catechin synthesis.

This paper mainly describes a spray drying method for the preparation of a variety of composite microspheres of energetic materials, including AP, RDX, β-HMX, and e-CL-20, which are commonly used in composite modified double base propellants. The composite microspheres were prepared with catalyst Cu-en to increase the contact area between the energetic materials and the catalyst. The results of powder XRD and EDX suggest that copper is mainly distributed in the interior of AP and e-CL-20 composite particles, but mainly dispersed on the surface of β-HMX and RDX microspheres. The data of the DSC test show that the catalytic effects of the composite microspheres exhibit the best performance, compared with the simply physically mixed catalyst and the energetic materials. The exothermic peak temperatures of AP, RDX, β-HMX, and e-CL-20 are reduced to 305.4 °C, 228.6 °C, 280.2 °C and 232.0 °C, respectively. The results show that the composite microspheres can enlarge the contact area between the catalyst and the energetic materials thus enabling an enhanced catalytic effect.

This study presents the combinative merits of facet effect and the graphene oxide (GO) hybrid of Ag3PO4 photocatalyst. First, Ag3PO4 tetrahedra with exposed {111} facets were controllably prepared via an ethanol–water ion exchange strategy at room temperature. The amount of ethanol was crucial to regulate the orientation growth of Ag3PO4 crystals along {111} planes through the balance of coordination and adsorption. The sample exhibited an enhanced visible-light photocatalytic efficiency of 3.3-fold for pollutant degradation as compared to that of Ag3PO4 particles due to the active facets. GO/Ag3PO4 hybrid was then constructed based on the electrostatic interaction between Ag+ enriched {111} facets and negatively charged GO sheets. The photocatalytic activity of the hybrid increased by 4.6-fold with admirable recyclability as compared to that of the bare Ag3PO4 tetrahedra. Systematical optical and photoelectrochemical characterizations revealed that the hybrid exhibits extended light absorption and significantly accelerated carrier transfer due to the coaction of unique charge mobility of GO, electronic effect of trace Ag and increased catalytic active sites. A possible migration mechanism of photoinduced carriers at the interface of GO/Ag3PO4 tetrahedron is proposed based on the above analyses, detected oxidative species and band positions of Ag3PO4 tetrahedra. This study provides new insight into the rational design of carbonaceous material-hybridized semiconductor photocatalysts with facet dependency.

The electronic structure and optical properties of O adsorbed ReS2 monolayer under different biaxial strains were studied through Density Functional Theory. Strain reduces the band gap of O adsorbed ReS2 monolayer, the band gap varies greatly reaching 1.509 eV under strain of −10%. Both the absorption intensity and reflectivity change significantly under strains. The adsorption coefficient reaches maximum value of 27.08 × 104 cm−1 under strain of −10% within the ultraviolet range. Our research shows that strain can effectively modulate the optoelectronic properties of O adsorbed ReS2 monolayer, which provides helpful guidance for the application of ReS2 in nanoscale optoelectronic devices.

Three chelating energetic materials (CEM), [Co(SCZ)2(H2O)2](TNR)(H2O)2 (1), [Ni(SCZ)2(H2O)2](TNR)(H2O)2 (2) and [Zn(SCZ)2(H2O)2](TNR)(H2O)2 (3, SCZ = semicarbazide, H2TNR = styphnic acid), were synthesized and characterized by elemental analysis, FTIR spectroscopy and single-crystal X-ray diffraction analysis. Single-crystal X-ray diffraction analysis revealed that 1 mainly exhibits swathe construction, whereas 2 and 3 manifest grating structure. Thermal decomposition behaviors of 1–3 were studied by differential scanning calorimetry (DSC). The critical temperature of thermal explosion, the entropy of activation (ΔS≠), the enthalpy of activation (ΔH≠), and the free energy of activation (ΔG≠) were also calculated. Sensitivity tests revealed that 1–3 are insensitive to mechanical stimuli, and that the grating structure (2 and 3) shows better shock resistance and flame retardant property than the swathe construction (1) at the molecular level.

The thermal performance of high-energy hydrazine nitrate complexes [Zn(N2H4)2(NO3)2]n, [Cd(N2H4)2(NO3)2]n, [Co(N2H4)3](NO3)2 and [Ni(N2H4)3](NO3)2 (signed as ZnHN, CdHN, CoHN and NiHN) was researched systematically. The thermal behavior, kinetics, thermal safety and storage life of them were investigated by the DSC, TG and dynamic pressure measuring thermal analysis method. The thermal decomposition of CdHN and ZnHN with NO3 − as ligand is more complicated than CoHN and NiHN with NO3 − as counterion indicating that similar structures have some influence on the thermal properties, but there is no necessary relationship. DSC curves and TG mass-loss stages of CdHN and ZnHN are similar but their thermal decomposition mechanism is quite different.

The aerobic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA), a promising renewable monomer to produce bio-based polymers such as polyethylene furanoate (PEF), has recently emerged as the subject of increasing interest. Here, holey 2 D Mn

Deregulation of miR-153 has recently been observed in several common human cancer, while miR-153 serves an oncogene or tumor suppressive role in different cancer types. Previously, miR-153 has been identified to be overexpressed in prostate cancer. miR-153 played an important role in promoting proliferation of human prostate cancer cells and presented a novel mechanism of microRNA-mediated direct suppression of phosphatase and tensin homolog (PTEN) expression in prostate cancer cells. Until now, little is known about the clinical significance of miR-153 expression in prostate cancer. The miR-153 expression in 143 pairs of prostate cancer and adjacent non-cancerous prostate tissues was measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis. Student t test was conducted for intergroup comparison. Pearson correlation test was used for correlation analysis. Survival curves were carried out by the Kaplan–Meier method and evaluated using the log-rank test. Multivariable Cox proportional hazard risk regression model was performed to screen the independent factor affected the prognosis of prostate cancer patients. qRT-PCR analysis showed that the expression of miR-153 was significantly increased in the prostate cancer tissues in comparison with the adjacent noncancerous prostate tissues (P

Research aimed at reducing the sensitivity of primary explosives with excellent ignition performance is of great significance for their practical application. In this work, we theoretically studied the effect of inserting the primary explosive copper azide (Cu(N3)2) into single-walled carbon nanotubes (SWCNTs) on the sensitivity of the explosive to changes in hydrostatic pressure. The electronic structure of Cu(N3)2 was found to be more sensitive to external pressure than lead azide, which is consistent with their experimental impact sensitivities. A composite of Cu(N3)2 molecules and SWCNTs (Cu(N3)2/CNTs) was prepared in which the components mainly interacted electrostatically and the Cu(N3)2 molecules formed semi-arc structures along the nanotube walls, rather than exhibiting their usual planar structure. The electrostatic potential and electronic structure of the composite indicate that it is more stable than crystalline Cu(N3)2. Notably, combining the Cu(N3)2 with the SWCNTs reduces the sensitivity of the Cu(N3)2 to external pressure, implying that carbon nanotubes can reduce the sensitivity of Cu(N3)2. This work should aid the development of highly efficient green primary explosives.

Based on the advantages of energetic complexes and cocrystallization, a novel energetic complex cocrystal [Mn(SCZ)3](TNR) (H2O) · [Mn(SCZ)2(H2O)(TNR)](H2O) (SCZ: semicarbazide, TNR: 2,4,6-trinitroresorcinol) was synthesized through a one-step reaction. This cocrystal contains equal units of [Mn(SCZ)2(H2O)(TNR)](H2O) and [Mn(SCZ)3]TNR(H2O). The molecules of the two units arrange mutually crosswise in the cocrystal and the benzene rings of TNR can form one-dimensional self-assemblies through π-π stacking. The thermal decomposition of the cocrystal is complicated with one endothermic process and three exothermic processes in the DSC curve. The complex [Mn(SCZ)2(H2O)(TNR)] · 3(H2O) was synthesized and the temperature of the major exothermic peak of the cocrystal is higher than observed for this complex.

Uniform α-Fe2O3/amorphous TiO2 core-shell nanocomposites were prepared via a hydrolysis method and α-Fe2O3/anatase TiO2 core-shell nanocomposites were obtained via a post-calcination process. The structure and morphology of the products were characterized by powder X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and scanning electron microscopy. Amorphous TiO2 nanoparticles with diameters of ten to several tens nanometer were formed on the surface of α-Fe2O3 nanoparticles and the coverage density of the secondary TiO2 nanoparticles in the composite can be controlled by varying the concentration of Ti(BuO)4 in the ethanol solution. The visible-light photocatalytic properties of different products towards Rhodamine B(RhB) were investigated. The results show that the α-Fe2O3/amorphous TiO2 exhibits a good photocatalytic property owing to the extension of the light response range to visible light and the efficient separation of photogenerated electrons and holes between α-Fe2O3 and amorphous TiO2.

Seven new 3d–4f heterometallic coordination polymers, [Ln(CuL)2(Hbtca)(btca)(H2O)]·2H2O (Ln = TbIII 1, PrIII 2, SmIII 3, EuIII 4, YbIII 5), [Nd(NiL)(nip)(Rnip)]·0·25H2O·0.25CH3OH (R= 0.6CH3, 0.4H) 6 and [Nd2(NiL)(nip)3(H2O)]·2H2O 7(CuL or NiL, H2L = 2, 3-dioxo-5, 6, 14, 15-dibenzo-1, 4, 8, 12-tetraazacyclo-pentadeca-7, 13-dien; H2btca = benzotriazole-5-carboxylic acid; H2nip = 5-nitroisophthalic acid) have been synthesized by a solvothermal method and characterized by single-crystal X-ray diffraction. Complexes 1–5 exhibit a double-strand meso-helical chain structures formed by [LnIIICuII2] units via the oxamide and benzotriazole-5-carboxylate bridges, while complex 6 exhibits a four-strand meso-helical chain formed by NdNi unit via the oxamide and 5-nitroisophthalate bridges. Complex 7 consists of a 2D layer framework formed by four-strand meso-helical chain via the nip2− bridges. Moreover, the magnetic properties of them were investigated, and the best-fit analysis of χMT versus T show that the anisotropic contribution of Ln(III) ions (arising from the spin-orbit coupling or the crystal field perturbation) dominates (weak exchange limit) in these complexes(for 3, λ = 214.6 cm−1, zj’ = −0.33 cm−1, gav = 1.94; for 5, Δ = 6.98 cm−1, zj’ = 1.53 cm−1, gav = 1.85).

Based on the law of approach to saturation and the experimental results of magnetic moments of PrNi 5 , the exchange interaction-effective field in PrNi 5 is given under a strong magnetic field and at low temperature, which is shown as H i n = a H e + b H e 3 / 2 + c H e 2 . By using the exchange interaction-effective field, the Zeeman Hamiltonian can be calculated directly without using the self-consistent method. Furthermore, the magnetic moment, the magnetic entropy and the magnetic entropy changes of PrNi 5 are calculated in the ranges of 0 H e 20 T and 2 T 60 K . The obtained results are in good agreement with the experimental data. The investigation indicates that the exchange interaction-effective field in PrNi 5, under the strong magnetic field and at low temperature, is only a function of the applied field.

Hematopoietic pre-B-cell leukemia transcription factor (PBX)-interacting protein (HPIP/PBXIP1) is a nucleo-cytoplasmic shuttling protein, and its expression is associated with cancer aggressiveness. However, the role of HPIP in ovarian cancer is still unclear. Here, we aimed to clarify the role of HPIP in epithelial‐mesenchymal transition (EMT) process of ovarian cancer cells, stimulated by transforming growth factor (TGF)-β1. In this study, we found that HPIP was highly expressed in ovarian cancer cells, and TGF-β1 treatment induced HPIP expression in ovarian cancer cells. In addition, knockdown of HPIP suppressed TGF-β1-induced EMT and migration/invasion in ovarian cancer cells. Moreover, knockdown of HPIP significantly blocked the phosphorylated pattern of both PI3K and Akt induced by TGF-β1 in SKOV3 cells. In conclusion, the present study showed that HPIP silencing might prevent TGF-β1-induced EMT in ovarian cancer cells. Thus, HPIP may be a potential therapeutic target for the treatment of ovarian cancer.

For general dynamic pick and place tasks that the objects are transferred with high speed by the conveyor belt, the capability of a delta robot to track the traveling objects is very important for the efficiency. To meet the needs of precision and smooth control, a computed-torque control scheme for conveyor tracking is implemented in this paper. For higher efficiency and accuracy, computer vision system, encoder and conveyor belt region are incorporated into the control scheme. Dividing the conveyor belt into three regions, the robot is commanded to track, pick and give up according to the subregions. Conveyor belt is equipped with an encoder that provides the controller with real-time position and speed of the belt. Based upon those informations, the controller automatically compensates the end positions with respect to the belt to adjust for the position of the conveyor. Then, the conveyor tracking problem is converted to a subregional tracking problem.

Bi2O2CO3 clusters made up of ultrathin nanosheets with predominated {001} facets were facilely synthesized via a template-free hydrothermal strategy at a mild temperature of 60 °C. Na2CO3 dosage and reaction temperature are confirmed to be key parameters to obtain the hydrolysis product of (Bi2O2)2+ from bismuth nitrate and provide a suitable microenvironment for the assembly of nanosheets. The sample exhibits obviously improved photocatalytic activity for the degradation and mineralization of Rhodamine B compared with thicker Bi2O2CO3 plates of less exposed {001} planes, with the reaction rate constant k enhanced by 3.4 fold. Photoluminescence and electrochemical impedance results confirm that the {001} facets are reactive and favorable for the separation and migration of photogenerated carriers, which primarily account for the superior photocatalytic behavior of the Bi2O2CO3 clusters. In addition, the enhanced specific surface area should also contribute to the improved photocatalytic activity. Based on the band edge positions of Bi2O2CO3 and the redox potentials of detected oxidative species, a possible migration mechanism of photogenerated e−/h+ pairs on the surface of Bi2O2CO3 is proposed. This work provides some new insight into the rational design and synthesis of facet-dependent semiconductor photocatalyst under mild conditions.

New low-loss NiZrNb2O8 microwave dielectric ceramics were synthesized via conventional mixed oxide route. The morphology, crystal structure and microwave dielectric properties were investigated. It exhibited a monoclinic wolframite crystal structure, with the space group of P2/c ( C 2 h 4 ) . The lattice energy was carried out to evaluate the structural stability and sintering characteristics. Two kinds of grain shapes in dense samples, with similar elements ratios, were observed. Variations in the dielectric constant (er) were analyzed by relative density and porosity-corrected polarizability. The quality factor (Q × ƒ) was correlated with packing fraction and grain growth. The temperature coefficient of resonant (τƒ) was depended on the dielectric constant. The typical microwave dielectric properties of NiZrNb2O8 were er = 23.77, Q × ƒ = 40280 GHz, τƒ = −27.5 ppm/°C, sintered at 1200 °C.

This study introduces the preparation of sub-micron composite particles of phloroglucinol-Fe and Cl-20 (Fe-Ph/Cl-20) with a spherical shape using spray drying technology. The influences of solution concentration and temperature on the morphology and particle size of the Fe-Ph/Cl-20 particles were studied using a scanning electron microscope (SEM) and a laser particle analyzer. The results show that when the concentration (ethyl acetate as solvent) of Fe-Ph/Cl-20 (0.3 g : 10 g) is 10.30 g/100 g and the temperature is 80 °C, the Fe-Ph/Cl-20 particles are well-defined spherical particles (D50 958.96 nm and D90 1647.63 nm). Thermal decomposition of Fe-Ph/Cl-20 is studied using a differential scanning calorimeter (DSC). The DSC illustrates that the apparent activation energy of Fe-Ph/Cl-20 is reduced by 41.9 kJ mol−1. The spray drying technology provides theoretical support and introduces a new direction for preparing the sub-micron composite particles of high explosives and combustion catalysts.

Flower shaped WO3 architectures weaved up of ultrathin nanorods with oriented {001} facets were successfully prepared via a facile ethanol/water solvothermal strategy, at a low temperature of 100 °C for 4 h. Characterizations of phase, morphology, microstructure, optical absorption, BET surface area, photoluminescence, photoelectrochemical properties and photocatalytic behavior were systematically explored. The volume ratio of ethanol and water was confirmed to be a key parameter in regulating the morphology and microstructure of WO3 by tuning the dielectric properties of the mixed solvent. The {001} faceted WO3 structures exhibit improved photocatalytic activity for the degradation of methyl orange with the reaction rate constant k enhanced by 2.1 fold, compared to the hydrothermal counterpart assembled by thick, individual WO3 nanorods. The active {001} facets with faster charge migration and enhanced surface area with more adsorption sites account for the excellent photocatalytic behavior. In addition, the active species in the photocatalytic reaction were investigated in detail, using terephthalic acid capture, ESR and radical scavengers. Combining the band edge positions of WO3 and the redox potentials of the active species, a possible migration mechanism of photogenerated e−/h+ pairs on the surface of WO3 is proposed. This work provides some new insights into the rational design and synthesis of facet-dependent 3D semiconductor photocatalysts.

Uniform ZnO nanospheres have been successfully synthesized through a facile solvothermal process. The structure and morphology of the products were characterized by powder X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The results showed that the products were ZnO nanospheres of 300–350 nm in diameter, which were composed of nanoparticles of ca. 5–10 nm. The size of the nanospheres can be tuned from ca. 300 nm to 1 μm by changing the concentration of the reactants. The gas sensing performance of the ZnO nanospheres with different size were investigated, which indicated that the ZnO nanospheres exhibited good gas sensitivity and selectivity towards n-butanol. In addition, the gas sensitivity of the ZnO nanospheres exhibited obvious size-dependent effect.

In this study, an effective BiOBr/Bi2O2CO3 p-n heterojunction was established via a precipitation conversion method at ambient temperature. The light response of the hybrid was broadened for 16 nm compared with that of Bi2O2CO3. More importantly, the charge transfer in BiOBr/Bi2O2CO3 heterojunction was greatly promoted as evidenced by photocurrent, ESI and PL results. So the photocatalytic ability of BiOBr/Bi2O2CO3 was greatly improved towards degradation of organic pollutants. The sample of Br amount of 0.094 wt% showed the optimal photoactivity for RhB degradation, with a rate constant k of 14.8 times as much as that of Bi2O2CO3. The reason is ascribed to the established built-in electrical field and resulted band matching between BiOBr and Bi2O2CO3. Based on the results, the migration mechanism of photoinduced charges at the interface of the heterojunction was put forward. This work provides a useful perspective in design and fabrication of Bi(III)-based heterostructure with an enhanced photocatalytic activity.

The electronic and optical properties of black phosphorene with different bent angle are studied using density functional theory based on the first-principles. Within the scope of our study, it was found that the phosphorene becomes less stable with the increasement of bending deformation. Bending deformation has great impact on the electronic and optical properties on phosphorene. The bandgap degrades a little at [Formula: see text] bent angle, and then increases when the bent angle does not surpass [Formula: see text], after which the bandgap decreases with the increasement of bending deformation. Besides, the bandgap of black phosphorene occurs a direct to indirect transition at [Formula: see text] bent angle. The bandgap calculated by HSE06 is larger than PBE functional, but the law of changes is consistent. By analyzing the density of states, we concluded that all the undeformed and deformed phosphorene structures have a strong sp orbital hybridization. Besides, the p orbits have narrower gap than s orbits, which causes the narrower bandgaps of these structures. From the analysis of optical properties, we concluded that the black phosphorene with [Formula: see text] bent angle has the highest absorption coefficient. All structures under bending deformation have higher reflectivity peak than intrinsic black phosphorene, among these structures, the black phosphorene with [Formula: see text] bent angle has the highest reflectivity. The novel optical property is observed at the [Formula: see text] deformed structure, it stops absorbing (reflecting) light first. Redshift and blueshift phenomena are observed at the highest absorption peak and reflectivity peak.

Black phosphorene (BP) has a high specific surface area due to its puckered honeycomb lattice structure, so it has great advantages in gas sensor applications. Doping and defects have a great effect on its sensitivity. Our aim is to obtain an insight into the sensing mechanism of black phosphorene towards CH2O, a hazardous organic compound. Based on the first-principles method of density functional theory (DFT), the sensing behaviors of the BP system, with intrinsic, Al doped, P vacancy-defected and P-vacancy and Al doping coexistent, before and after CH2O adsorption are studied. By establishing the structural models of four BP systems, the values of adsorption energy, energy band structure and charge transfer are calculated. Calculation results show that CH2O molecule prefers to be adsorbed perpendicular to the P vacancy-defected BP nanosheet with oxygen atom on the top site and close to the sheet. For the intrinsic, Al doped, P-vacancy and Al doping coexisting BP nanosheet, the CH2O molecule tilts towards the sheet surface. It is found that the CH2O adsorption on intrinsic BP nanosheet (adsorption energy is 0.179 eV) is very weak. In contrast, the adsorption of CH2O to the BP systems, with P vacancy-defected BP, Al doped, P-vacancy and Al doping coexistent, shows relatively high affinity (0.875, 0.542, 0.824 eV). Thus, Al doping, P vacancy or P-vacancy and Al-doping coexistence can substantially improve the adsorption ability of BP systems towards CH2O. In order to investigate the sensing mechanism of BP systems, the electronic properties such as the density of states, energy band and charge transfer are calculated. The change of energy gap of intrinsic BP nanosheet before and after CH2O adsorption is 0.024 eV, and that for P vacancy-defected BP nanosheet is zero. In addition, P atom vacancy has no effect on charge transfer. These suggest that the conductivity of intrinsic BP or P vacancy-defected BP nanosheet has not obviously changed, thereby, they are not suitable for sensor materials. For the BP system with Al doping or the coexistence of P vacancy and Al doping, it is obviously seen that an impurity level is generated in the energy band diagram, the effective band gap is significantly narrowed, indicating that the Al doping improves the sensitivity of BP. In addition, the charge transfer is significantly increased, which changes the carrier concentration and improves the electrical conductivity. Therefore, the BP system with Al doping or the coexistence of P vacancy and Al doping is expected to become a kind of new sensor material.

Based on the first-principles of density functional theory, this paper systematically studied the effect of tensile and compression deformation on the electrical properties of graphyne. The study show that the graphyne has an direct and adjustable band gap under deformation. Under uniaxial deformation, the band gap tend to be in the decline with the increase of the deformation, but under biaxial deformation, the band gap is positively correlated with the deformation, which increases with the rising of the tension deformation, and decreases with the increase of the compression deformation. The band gap value calculated by the HSE06 method is larger than what is obtained by the GGA method, but the shape characteristics of the band structure obtained by the two are basically the same, as well as the same trend between band gap and strain. With the tensile and compressive deformations increase, the charge transfer between C atoms in the graphyne is intensified. Compressive deformation makes the graphyne system more stable, while tensile deformation reduces the stability of graphyne. Compared with uniaxial, biaxial deformation has a more severe effect on the stability and band gap of the graphyne system, but less on charge transfer.

We systematically study a Kitaev chain with imbalanced pair creation and annihilation, which is introduced by non-Hermitian pairing terms. Exact phase diagram shows that the topological phase is still robust under the influence of the conditional imbalance. The gapped phases are characterized by a topological invariant, the extended Zak phase, which is defined by the biorthonormal inner product. Such phases are destroyed at the points where the coalescence of groundstates occur, associating with the time-reversal symmetry breaking. We find that the Majorana edge modes also exist for the open chain within unbroken time-reversal symmetric region, demonstrating the bulk-edge correspondence in such a non-Hermitian system., 8 pages, 4 figures