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We simulate the time-resolved decay process of the yellow band in GaN based on the first principles, and the simulated decay lifetimes are confirmed in our experiments.

We report a novel plastic deformation mechanism of bulk metallic glass composites (BMGCs) containing metastable $\ensuremath{\beta}\text{\ensuremath{-}}\mathrm{Ti}$ dendrites. Plastic deformation of the BMGCs beyond the ultimate tensile strength is mediated by cooperative shear events, which comprise a shear band in the glassy matrix and a continuous $\ensuremath{\omega}\text{\ensuremath{-}}\mathrm{Ti}$ band with a thickness of $\ensuremath{\sim}10\text{ }\text{ }\mathrm{nm}$ in the $\ensuremath{\beta}\text{\ensuremath{-}}\mathrm{Ti}$ dendrite. The cooperative shear leads to serrated shear avalanches. The formation of narrow $\ensuremath{\omega}\text{\ensuremath{-}}\mathrm{Ti}$ bands is caused by high local strain rates during the cooperative shear. The cooperative shear mechanism enriches the deformation mechanisms of BMGCs and also deepens the understanding of $\ensuremath{\omega}\text{\ensuremath{-}}\mathrm{Ti}$ formation.

We have investigated the mechanism of tunable luminescence in a bismuth doped ScVO4 matrix by using the first-principles calculations. It is found that some intrinsic defects generally exist in the matrix due to their low formation energies, while they have no remarkable effect in the optical band gap of the compound. The calculated formation energy of substitutional Bi at the Sc site is 2.0–3.3 eV lower than that of replacing V by Bi in various chemical environments. Yet, once there is an oxygen defect (vacancy) around a Bi atom, it is energetically preferable to form a defect complex, BiSc + VacO. Based on the calculated formation energy and the imaginary part of the dielectric function, the defect complex transfers between the neutral charge state and the 1+ charge state, which is ascribed to be responsible for the red bismuth photoemission observed in experiment. With the defect complex, tunable bismuth photoemission could be achieved by selectively controlling the content of hydrogen. Our calculations have shown that there is a passivation effect resulting from the re-padding of the oxygen defect by the hydrogen atom. This confirms the experimental observation of tunable bismuth luminescence due to the defect complex, leading to a potential facile design of other defect-controllable, micro- and nano-sized luminescent materials ranging from the visible to the near- and far-infrared spectrum.

Tin (Sn) halide perovskite absorbers have attracted much interest because of their nontoxicity as compared to their lead (Pb) halide perovskite counterparts. Recent progress shows that the power conversion efficiency of FASnI3 (FA = HC(NH2)2) solar cells prevails over that of MASnI3 (MA = CH3NH3). In this paper, we show that the organic cations, i.e., FA and MA, play a vital role in the defect properties of Sn halide perovskites. The antibonding coupling between Sn-5s and I-5p is clearly weaker in FASnI3 than in MASnI3 due to the larger ionic size of FA, leading to higher formation energies of Sn vacancies in FASnI3. Subsequently, the conductivity of FASnI3 can be tuned from p-type to intrinsic by varying the growth conditions of the perovskite semiconductor; in contrast, MASnI3 shows unipolar high p-type conductivity independent of the growth conditions. This provides a reasonable explanation for the better performance of FASnI3-based solar cells in experiments with respect to the MASnI3-based solar cells.

A phytochemical investigation on the aerial part of Phyllodium pulchellum led to the isolation of 16 compounds including five flavonoids (1–5), three lignans (6–8), four indole alkaloids (9–12), and four other-type compounds (13–16). Their structures were elucidated by their spectroscopic data analysis. Among them, 12 compounds (1, 2, 4–9, and 11–14) are reported from the genus Phyllodium for the first time, while compound 14 was isolated from the Leguminosae family for the first time and compound 11 was firstly reported in the plant kingdom. The chemotaxonomic significance of these compounds was also summarized.

The hybrid structures of polystyrene-b-poly(ethylene oxide) (PS-b-PEO) block copolymer and inorganic nanoparticles with good stability and biocompatibility have potential applications in drug delivery and bioimaging. Spherical co-assemblies of PS120-b-PEO318 and oleylamine-capped CdS quantum dots (QDs) are produced successfully in this work by adding water to a mixed common solvent, such as N,N-dimethylmethanamide (DMF)/chloroform, DMF/tetrahydrofuran (THF), or DMF/toluene. The energy dispersive X-ray (EDX) spectrum indicates that QDs are located at the interface between the core and shell of the spherical co-assemblies. The co-assembly process during water addition is traced by transmission electron microscopy (TEM) and turbidity measurement. Spherical co-assemblies are formed through budding from bilayers of the block copolymer and QDs. The morphology of the co-assemblies is related to the miscibility of the QD-dispersing solvents with water and the morphology changes from a spherical to a vesicle-like structure with DMF/toluene. Increasing THF content in the mixed solvent causes morphological transitions from spherical co-assemblies to multi-branched cylinders and micelles where QDs are located in the central core. Increasing chloroform content yields vesicle-like structures with protruding rods on the surface. The mechanism of the morphological transitions is also discussed in detail.

Carbon (C) doping is essential for producing semi-insulating GaN for power electronics. However, to date the nature of C doped GaN, especially the lattice site occupation, is not yet well understood. In this work, we clarify the lattice site of C in GaN using polarized Fourier-transform infrared and Raman spectroscopies, in combination with first-principles calculations. Two local vibrational modes (LVMs) at 766 and $774\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}1}$ in C doped GaN are observed. The $766\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}1}$ mode is assigned to the nondegenerate ${A}_{1}$ mode vibrating along the $\mathbit{c}$ axis, whereas the $774\text{ }\text{ }{\mathrm{cm}}^{\ensuremath{-}1}$ mode is ascribed to the doubly degenerate $E$ mode confined in the plane perpendicular to the $\mathbit{c}$ axis. The two LVMs are identified to originate from isolated ${\mathrm{C}}_{\mathrm{N}}^{\ensuremath{-}}$ with local ${C}_{3v}$ symmetry. Experimental data and calculations are in outstanding agreement both for the positions and the intensity ratios of the LVMs. We thus provide unambiguous evidence of the substitutional C atoms occupying the N site with a $\ensuremath{-}1$ charge state in GaN and therefore bring essential information to a long-standing controversy.

An easy method is presented to fabricate monodisperse magnetic macroporous polymer beads (MMPBs). Waterin- oil high internal phase emulsion (HIPE) is prepared by emulsifying aqueous iron ions solution in an oil phase containing monomers. The HIPE is introduced into a simple microfluidic device to fabricate monodisperse (water-in-oil)-in-water double emulsion droplets. The droplets serve as microreactors to synthesize Fe3O4 nanoparticles and are on-line polymerized to form MMPBs. The prepared MMPBs display uniform size, interconnected porous structure, superparamagnetic behavior and uniform distribution of Fe3O4 in polymer matrix. The MMPBs are characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM). We believe that this method is a universal technique in preparing macroporous nanocomposite beads.

This paper analysis the working mechanism and structure of vortex flowmeter and the street flow meter hardware circuit design. Signal conditioning circuit was designed including ultrasound transmitter receiver processing circuit, traffic signal conditioning circuit ,programmable amplifier and anti aliasing filter circuit.The temperature measuring circuit , infrared communication circuit and supersonic signal control electric circuit. These circuit to ultrasound dedicated chips UTA6902 as core. The vortex flowmeter was design of the design of liquid crystal display program, the design of temperature programming and the design of ultrasonic signal acquisition and processing program. It can be verified in the experiment.

ZnGa2O4:Mn, as a distinct long persistent luminescence (PL) phosphor with green emission, has attracted intensive interest for display devices and security applications. We have systemically investigated the role of intrinsic defects in the PL of pristine and Mn doped ZnGa2O4 by first-principles calculations. It is found that the self-activated PL is attributed to the electron traps induced by VO and hole traps by VZn and ZnGa. The doped Mn will be energetically favored at the tetrahedral sites rather than octahedral sites under an Mn-rich condition. In contrast, the site preference of Mn largely depends on the chemical potentials of Zn and Ga under Mn-poor condition. The existence of the antisite defect ZnGa, however, promotes the stability of Mn at octahedral sites significantly, forming corresponding defect complexes. The crystal field strength is significantly enhanced, while the spin splitting is reduced on Mn in the defect complex, which introduces additional near-infrared luminescence of PL as confirmed by our experiment.

Objective To assess the influence of post-admission random hyperglycemia of elderly patients suffering from acute myocardial infarction (STEMI) with elevation of ST segment on cardiac function, coronary perfusion, and the prognosis of one year later. Methods A total of 137 STEMI patients aged over 75 years were enrolled in present study, including 69 cases of random blood glucose ≥11mmol/L (hyperglycemia group) and 68 cases of random blood glucose

The author constructs a class of indecomposable non-degenerate solvable Lie Algebras \( \tilde g \) corresponding to a Cartan matrix A over the field of complex numbers and we determine all their derivations.

Controlled morphology modulation of graphene carbon nitride (g-C3N4) is successfully realized from bulk to 3D loose foam architecture via the blowing effect of a bubble, which can be controlled by heating rate. The loose foam network is comprised by spatially scaffolded few-atom-layer interconnected flakes with the large specific surface area, as supporters to prevent agglomeration and provide a pathway for electron/phonon transports. The photocatalytic performance of 3D foam strutted g-C3N4 toward RhB decomposition and hydrogen evolution is significantly enhanced with the morphology optimization while its excellent optoelectronic properties are maintained simultaneously. Herein, the ultrathin, mono-, and high-quality foam g-C3N4 interconnected flakes with controlled layer are facilely obtained through ultrasonic, thus overcoming the drawbacks of a traditional top–down approach, opening a wide horizon for diverse practical usages. Additionally, the layer control mechanism of 3D hierarchical structure has been explored by means of bubble growth kinetics analysis and the density functional theory calculations.

Point defects play an important role in the photoelectrical properties of semiconductor materials, and they can be luminescence centers. However, the relationships among the observed luminescence wavelengths, intensities, and the microscopic processes are in most cases unknown, or depend heavily on parameter fitting. In this work, the light-emitting quantum efficiencies for point defects using ab initio density functional theory are calculated. The study of radiation recombination for electrons and nonradiation recombination for holes is reported here. The results show that the defect CN transition between “−” and “0” charged levels and the defect CN+ON transition between “0” and “+” charged levels both may be responsible for the yellow luminescence (YL) which is observed in experiment. Moreover, the calculation shows significant thermal quenching of the YL starting at 480 K due to re-excitation of hole into the valence band from the point defects, which is in relatively good agreement with the experimentally observed value. This work shows that it is possible to use ab initio calculations to understand the microscopic mechanisms and the competitions among different channels for the light emissions caused by defects.

In the present paper, two SERS-active substrates (silver mirror and HNO3 etched Ag foil) were prepared for thiuram detecting and studying. SERS can provide the molecular vibrational model and structure information of thiuram at low concentration, thus providing very valuable information regarding the structure of the adsorbed molecules. This technique also allows for the in situ study of this molecule when adsorbed on a silver surface and the identification of the chemical state when they are adsorbed on the surface of silver substrate. The SERS study of thiuram was carried out at several adsorbtion concentrations, revealing that two different coordination complexes having different geometries (monodentate and bidentate) are possible adsorbed on the silver surface. These results have a significant importance regarding the understanding of the potential environmental impact of these molecules.

Vasoconstriction and vascular hypersensitivity to serotonin were previously shown in animal models of adventitia injury. We investigated the contribution of angiotensin II (AngII)/AngII receptors and oxidative stress to vascular contractility and reactivity in this model.Wistar Kyoto rats were divided into 3 groups: normal (n = 6, no any intervention, only for measuring the serum AngII concentration), vehicle (n = 12, collared), and valsartan (n = 12, collared + valsartan 30 mg×kg(-1)×d(-1)). After one week of treatment, adventitia injury was induced by positioning a silicone collar around the right carotid artery for one week. Blood flow and vascular reactivity to serotonin were determined one week after injury, the blood from left ventricle was taken to measure the serum AngII concentration by ELISA, and carotids were harvested for morphometry and Western blot analysis.Adventitia injury induced lumen cross-sectional area reduction (-44% vs. -5%), media diameter increase (62% vs. 10%), blood flow reduction [(2.79 ± 0.22) vs. (4.33 ± 0.84) ml/min] were significantly attenuated by valsartan. The increased vascular reactivity sensitivity to serotonin in vehicle group was also significantly reduced in valsartan group. Serum AngII concentration was significantly increased in vehicle group [(45.21 ± 4.52) pg/ml vs. (19.83 ± 0.5) pg/ml in normal rats, P = 0.0148] and the expression of AngII type 1 (AT(1)) receptor, AngII type 2 (AT(2)) receptor, as well as p22(phox) in collared arteries were significantly upregulated. Valsartan did not affect the AT(1) receptor expression but further increased serum AngII concentration [(89.73 ± 20.44) pg/ml vs. (45.21 ± 4.52) pg/ml, P = 0.001], and AT(2) receptor expression, while downregulated p22(phox) expressions.Collar-induced adventitia injury resulted in chronic vasoconstriction and vascular hypersensitivity to serotonin via increased serum AngII level, upregulated AngII receptors expression in the vascular well, and activated local oxidative stress. These changes could be blocked by valsartan suggesting a crucial role of AngII/AngII receptors on vascular contractility and reactivity changes in this model.

Tongxinluo (TXL) is a traditional Chinese medicine that is developed on the meridian theory of traditional Chinese medicine, with the function of alleviating the angina. The present study was undertaken to explore the molecular mechanism of TXL in treating the pectoris angina through observing the effectiveness of TXL superfine powder on the vasoconstriction and the activation of RhoA/Rho-kinase pathway induced by the injury of the adventitia.36 male Wistar Kyoto rats were assigned to 3 treatments (n=12): vehicle, TXL (400 mg kg(-1) day(-1)) and fasudil (15 mg kg(-1) day(-1)). After 1 week of treatment, adventitia injury was induced by positioning a silicone collar around the right carotid artery for 1 week. Blood flow and vascular reactivity to serotonin were determined 1 week after injurying, the both sides of carotids were harvested for morphometry, Western blotting analysis and RT-PCR analysis.Adventitia injury leaded to histological changes of vasoconstriction with the lumen cross-sectional area of 44.7% (p0.001) decreasing and the media diameter of 62.31% (p0.001) increasing, accompanying by the reduction of the blood flow and the increase of vascular reactivity sensitivity to serotonin. Treatment with both TXL superfine powder and fasudil can prevent the development of vasoconstriction, improve the carotid blood flow and normalize the vascular hypersensitivity to serotonin. Adventitia injuring of the rat carotid increased the expression of Rho-kinase mRNA and p-MYPT1(Thr696) protein by 1.78-fold (p0.05) and2-fold respectively (p0.05). TXL reduced the expression of Rho-kinase mRNA and p-MYPT1(Thr696) protein by 54.2% (p0.05) and 57.1% (p0.05) respectively in collared arteries. Fasudil restrained the p-MYPT1(Thr696) protein expression by 63.8% (p0.05) in collared arteries, did not affect the collar-induced the increase of Rho-kinase mRNA expression (p0.05).Treatment with TXL, similar to that with fasudil, can effectively prevent collar-induced vasoconstriction and vascular hyperreactivity to serotonin through inhibiting the RhoA/Rho-kinase pathway.

To compare therapeutic effects of acupuncture, moving cupping, blood-letting puncture and medicine on chloasma.One hundred and seventy-six cases of chloasma were randomly divided into two groups. The acupuncture, moving cupping, blood-letting puncture group was treated with acupuncture at Ashi points, Xuehai (SP 10), Sanyinjiao (SP 6), moving cup at The Governor Vessel and The Urinary Bladder Channel on the back and then blood-letting puncture at Dazhui (GV 14), Feishu (BL 13), Geshu (BL 17), Xinshu (BL 15), Ganshu (BL 18) and nearby more severe purple stasis regions, and the medication group was treated with oral administration of Vit E and Vit C. Their therapeutic effects were observed after 3 courses.The total effective rate was 96.7% in the acupuncture, moving cupping, blood-letting puncture group and 51.2% in the medication group with a significant difference between the two groups (P0.05).The therapeutic effect of acupuncture, moving cupping, blood-letting puncture on chloasma is better than that of the medicine.