Search

At present, inhibitors have been widely used in the field of coal fire prevention and control, but there are some defects in the use of them. So it is necessary to find a new practical and economical inhibitor. Dissolvable tiny-foam extinguisher (DTE) is environment-friendly, high in thermal stability, and fast in cooling. In view of the good performance of the product, the thermal behavior effects of DTE on coal spontaneous combustion were investigated through experimental tests. A scanning electron microscopy was used to study changes in the surface microstructure of raw coal after DTE treatment. Laser thermal conductivity analysis and simultaneous thermal analysis were used to test the effects of DTE at mass fraction of 0%, 5%, 10%, and 15% on the thermophysical properties, mass loss, characteristic temperature, and heat release of coal during heating. The surface of the DTE-treated coal sample was covered in a dense film. The treated coal sample had lower thermal diffusivity and thermal conductivity values and a higher specific heat capacity. Moreover, coal treated with DTE showed no obvious oxygen absorption or mass gain during initial heating, and the dry cracking temperature was greatly increased by 37 °C, 53 °C, and 100 °C, respectively. The initial heat release temperature increased by more than 170 °C, and the amount of the initial heat absorption was more than 52.2 times that of untreated samples. Oxidation kinetics were applied to calculate the activation energy of the coal during thermal decomposition and ignition, and the activation energies of the treated samples at the thermal decomposition and combustion stages increased by 161%, 179%, and 173%, respectively. From these results, we concluded that DTE could inhibit heat accumulation by blocking oxygen contact with the coal and greatly reducing heat release during heating. Besides, only a small quantity of DTE was needed to effectively inhibit coal self-ignition. These results provide reference for the field application of DTE in restraining coal spontaneous combustion.

A simple method for the preparation of patterned graphene electrodes by applying patterned copper film as the masking layer is demonstrated. As-prepared graphene pattern shows well-defined and straight boundary line. High-quality patterned graphene electrode possesses a low average sheet resistance of 556 Ω/sq meanwhile its transmittance exceeds 96% at 550 nm. The 4 × 2 organic light-emitting diodes array with patterned graphene electrode further proves the practical application of this simple patterned technology. Corresponding device exhibits a maximum luminance of 44 k cd/m2 at 15 V and current efficiency of 24 cd/A at 6 V. This patterned graphene electrodes also have great potential in application of flexible printed electronics and display.

We report an omnidirectional light absorption enhancement of a perovskite solar cell (PSC) using antireflection (AR) film with soft imprinted microstructures from master molds via holographic lithography technology, which has high throughput and repeatability. The PSC’s omnidirectional power conversion efficiency (PCE) enhancement is achieved by reducing Fresnel surface reflections and enhancing the optical path length. The maximum PCE of PSCs with AR film is up to 20.27%, corresponding to an absolute increase of 0.93% compared to 19.34% of control devices. Significantly, the enhancements of PCE increase with incident angle enlargement, which attributes to more effective Fresnel surface reflection suppression. Moreover, AR films exhibit water and dust repellent properties due to hydrophobicity, which is beneficial for PSC’s long-term stability and light harvesting.

To obtain rational environment adaptability design solution of wind turbine, a fuzzy environment adaptability design method of wind turbine based on core design platform is promoted. Firstly, the core design platform is built based on main structure of wind turbine irrelevant with environment factors. Secondly, the 1:n mapping relationship between environment factor set and environment adaptability technology set is created. Thirdly, the fuzzy relationships between environment adaptability technologies and environment factors are researched, and the relationships include dependency and contradiction. Finally, the quality function deployment (QFD) technology is used to obtain rational environment adaptability design solutions of wind turbine in the known condition of complicated environment factors. The feasibility and availability of the method above mentioned are validated by an example.

4, 5-dicyano dimethyl phthalate was an intermediate of the synthesis of phthalocyanine compounds substituted carboxyl. Under the existence of the solvent methanol, 4, 5-dibromo dimethyl phthalate was synthesized by 4,5-Dibromophthalic acid and thionyl chloride.Then it was with cuprous cyanide to get 4,5-dicyano dimethyl phthalate. By studying the process conditions, we got the optimal reaction conditions of 4,5-Dibromo dimethyl phthalate which was thionyl chloride: 4,5-Dibromophthalic acid (2.5:1.0 , molar ratio) and by enlarging 10 times of the experimental conditions, we got the yield 86.4% which was higher than the reported 66.8%.And the optimal reaction conditions of 4,5-dicyano dimethyl phthalate was that high purity argon, absolutely anhydrous DMF, cuprous cyanide and 4,5-Dibromo dimethyl phthalate whose molar ratio were 4.0:1.0. By enlarging 10 times of the experimental conditions, we got the yield 19.0%.

PH1000/graphene (Gra) composite film with thermally-induced wrinkles has been employed as an electrode in organic solar cells (OSCs) to enhance the device efficiency. The wrinkled PH1000/Gra composite electrode exhibits excellent transmittance of 88.5% at 550 nm, decreased sheet resistance of 147.5 Ω sq−1 and appropriate work function of ~4.9 eV compared to pristine graphene. OSCs with wrinkled composite electrode possess enhanced short circuit current (JSC) compared to that of planar devices due to the wrinkles-induced enhancements in light absorption and charge collection. The power conversion efficiency (PCE) of OSCs with wrinkled composite electrode is 4.67%, which is 60% or 35% higher than that of planar devices based on the pristine graphene (2.93%) or PH1000 (3.45%) electrode, respectively. Corresponding PCE is comparable to that of the conventional ITO-based OSCs (5.08%). Even better, flexible OSCs with PH1000/Gra composite electrode exhibited excellent mechanical stability compared to ITO device. The enhanced efficiency of the OSCs demonstrates that the wrinkled PH1000/Gra composite electrode is a promising candidate for efficient and flexible optoelectronic application.

This paper describes the strong, weak ion exchange resin in combined application of the principle, calculation method, and combined with the actual introduction of the combined application of the equipment and operation mode.

To promote the structure analysis efficiency of multi-section & variable taper wind turbine tower, a novel method is proposed. The effective factors are analyzed for the performances of wind turbine tower, and the main parameters of it are found out. Resolution on rapid structure analysis is presented according to standardized FEA flows. The parameterized modeling method of towers vertical section profiles and optimal FEM meshing method are described. Finally, a rapid structure analysis software is completed to check the method, and the SUT 77-1500 wind turbine is taken as the example to verify the feasibility of the method

Compounds (S1-S3) containing triphenylamine donors, bipyridine acceptors and olefinic linkers were synthesized and characterized. Three compounds have excellent solubility in common solvents and tend to form solid films. The peaks of emission of S1-S3 are in the range of 476nm-504nm on solid films, corresponding to blue light emission. S1-S3 have fluorescence lifetime exceeding 2.05ns and absolute fluorescence quantum yield above 22% in dilute chloroform solutions. Three compounds possess glass-transition temperatures superior to 63°C. The HOMO levels are in the range of -5.17eV - -5.13eV to facilitate hole injection. The properties of S1-S3 indicate that these compounds are promising candidates as hole-transporting materials or blue light-emitting materials in organic light-emitting devices.

The Bässler’s energy and position disorder model is used to study the relationship between molecular structure of hole-transport materials and performance of the photoreceptor. The result shows that dipolar moments of hole-transport materials (HTM) are inverse proportion to the half decay exposures (E1/2) of the Organic photoreceptors (OPC) which closely related with the hole-mobility of hole-transport layer. In this article Marcus hopping theory and DFT method are also used to calculate the hole-mobility of four hole-transport materials (HTM). The compare of the half decay exposures of OPCs used these material as hole-transport layer and hole mobility, dipolar moments of these molecules show that the E1/2 increases with decrease of hole mobility and dipolar moment.

Two hole-transporting materials containing triphenylamine unit, 4-(4-(di-p- tolylamino)styryl)-N,N-di-p-tolylbenzenamine (TM 1) and 4-(4-(4-(di-p-tolylamino)styryl) styryl)-N,N-di-p-tolylbenzenamine(TM 2), have been designed and synthesized in this paper, which using conjugated bonds as the bridge to connect two molecules of triphenylamine. The optical spectrum, thermo-stabilization and electrochemical properties of two compounds were studied. The results show that these compounds have blue emission, proper HOMO levels and high thermal stability. Furthermore, EL devices with the configuration of ITO/HTL/Alq3/Al show the activating voltages are 11V for TM 1 and 5.5V for TM 2, respectively. The maximal luminancce efficiencies are 1.135cd/A for TM 1 and 2.068cd/A for TM 2, respectively. The difference of EL performance indicates that TM 2 possessing better hole-transporting performance than that of TM 1.

Two novel organic hole-transporting materials have been synthesized by combination of triphenylamines (TPA) via π-conjugated bonds using Wittig reaction. The structures were characterized by NMR, FT-IR and HRMS. The optical, electrochemical and thermal properties of the materials were studied in detail. The results show that these two compounds have blue emission, proper HOMO levels and high thermal stability. Furthermore, a quantum chemical calculation on electron distribution of the two compounds was performed, which suggests the current synthesized materials would be promising candidates for hole-transporting materials.

The inorganic electrophoretic particles easily sedimentate and are not preferably dispersed in medium because their density is relatively big. Spheric and hollow TiOB2Bparticles were prepared against the core-shell polymer latex particles via a simple wet-chemistry route, using Ti(OBu)B4Bas a precursor. The particles¢ morphology was observed by atom force microscopy (AFM) images, scanning electron microscope (SEM) and transmission electron microscopy (TEM). The products were characterized by X-ray Diffraction (XRD) and TEM. TEM showed spheric and hollow particles with a diameter around 290 nm. The density (in the atmospheric pressure, 20°C) of TiOB2Bwas 2.21 g∙mLP-1P. Results showed that hollow framework could reduce the density of particles. The Zeta potentials were determined by micro-electrophoresis apparatus. TiOB2Bparticles had good electrophoretic property, and the Zeta potential was 5.25 mV.

Improved two step in-situ polymerization was applied in the preparation of urea- formaldehyde microcapsules used in microencapsulated electrophoretic display. The dispersion liquid which nano particles of titanium dioxide and carbon black dispersed in tetrachloroethylene was used as the electrophoretic liquid, and the electrophoresis microcapsules was prepared by urea-formaldehyde system. Melamine was used to modify the urea-formaldehyde microcapsules. The effect of different mole rates of urea and melamine to the surface morphology, mechanical strength, and sphericity of the microcapsules were studied. Electrophoretic performance of particles in melamine-urea-formaldehyde (MUF) microcapsules and urea-formaldehyde (UF) microcapsules were contrasted under the same condition. The results showed that as adding melamine in urea-formaldehyde, the time used to prepare microcapsules was shorter, and microcapsules were not easy aggregation during long time storage. When the mole rates of melamine and urea were from 2:8 to 5:5, the microcapsules with smoother surface (Fig.1), stronger mechanical strength and higher transmittance were obtained. Electrophoretic behaviors of particles in MUF (melamine and urea was 2:8 in mole rate) and UF microcapsules were tested under the same condition, respectively. It was shown that particles in MUF microcapsules could be seen significantly moving at the electric field of 10 V/mm, and the response time of these particles was 500 ms at the electric field of 20 V/mm，and it was shorter than 200 ms at the 50 V/mm electric field (Fig.2). On the contrast, the response time of particles in UF microcapsules was greater than 10 s at the electric field of 20 V/mm.

Hollow TiOX nano-spheres have been successfully prepared using hollow core-shell latex particles as template, which involves the deposition of inorganic coating on the surface of hollow core-shell latex particles and subsequent removal of the latex particles by calcinations in air or ammonia gas. The formation route of hollow core-shell polymer particles is presented as follows: Firstly, poly-methyl methacrylate (PMMA) seed emulsions are prepared as the 'core'. Subsequently, the outer shell poly(styrene-co-methyl methacrylate) (PS-co-MMA) particles wrap on the surface of the core, the microspheres with core-shell have been prepared. Finally, Ti(OBu)4 is used as precursor for the preparation of hollow TiOX nanospheres. Transmission electron microscopy (TEM) and atom force microscopy (AFM) images of seed emulsions show they have the uniform size of about 470 nm. TEM of hollow core-shell polymers particles show they have an average diameter of about 500 nm. X-ray diffraction (XRD) analysis of TiO2 sample calcined presents that the strong absorptions is coordinated with the standard chart of rutile TiO2. TEM of TiO2 and TiO show hollow spheres well-dispersed with the diameter range of 300-400 nm and 350-400 nm, respectively. The density (in the atmospheric pressure, 20 °C) of TiO2 and TiO hollow spheres was 2.49 and 2.37 g∙mL-1, respectively. The Zeta potentials were 6.20 mV and 20.39 mV, respectively. Uniform hollow spheres show low density and good electrophoretic displays. The electrophoretic mobilities of white TiO2 and black TiO hollow spheres in tetrachloroethylene show they are suitable for electronic paper as background and display particles, respectively. It is anticipated that this method would present a potential toward the road of large-scale industrial production of TiOx hollow spheres.

Residual potential is a very important performance index of organic photoconductor (OPC). At present, research shows that the purity of charge transport material will seriously influence residual potential of OPC. But in past research we found that some OPC used charge transport material with very high purity still has very high residual potential. With quantum calculation and x-ray diffraction we found that some materials are optical isomer and some have cis-trans isomerism. So in order to improve performance of OPC we should separate isomerism.

Six bisazo compounds were synthesized by coupling 2-(4′-aminophenyl)-6-aminobenzoxazole as diazo component with N-phenyl-N′-(2-hydroxy-3-naphthoyl)urea derivatives, and characterized by ultra-violet and visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FT-IR) and elemental analysis (EA). Using these bisazo compounds as charge generation materials and CT-191(2-methyl-4-(N,N-dibenzyl) aminobenzoaldehyde-1,1-diphenylhydrazone) as charge transportation material, organic photoconductive devices were prepared. The result from photoconductivity measurement of the devices shows that the bisazo compound from N-(2-methylphenyl)-N′-(2-hydroxy-3-naphthoyl)urea has the best xerographic performance, V0=600 V, VR=30 V, Rd=15 V·s−1, E1/2=3.5 lx·s.

Action potential (AP) patterns and dopamine (DA) release are known to correlate with rewarding behaviors, but how codes of AP bursts translate into DA release in vivo remains elusive. Here, a given AP pattern was defined by four codes, termed total AP number, frequency, number of AP bursts, and interburst time [N, f, b, i].. The 'burst effect' was calculated by the ratio (γ) of DA overflow by multiple bursts to that of a single burst when total AP number was fixed. By stimulating the medial forebrain bundle using AP codes at either physiological (20 Hz) or supraphysiological (80 Hz) frequencies, we found that DA was released from two kinetically distinct vesicle pools, the fast-releasable pool (FRP) and prolonged-releasable pool (PRP), in striatal dopaminergic terminals in vivo. We examined the effects of vesicle pools on AP-pattern dependent DA overflow and found, with given 'burst codes' [b=8, i=0.5 s], a large total AP number [N = 768, f = 80 Hz] produced a facilitating burst-effect (γ[b8/b1] = 126 ± 3%), while a small total AP number [N=96, 80 Hz] triggered a depressing-burst-effect (γ[b8/b1] = 29 ± 4%). Furthermore, we found that the PRP (but not the FRP) predominantly contributed to the facilitating-burst-effect and the FRP played an important role in the depressing-burst effect. Thus, our results suggest that striatal DA release captures pre-synaptic AP pattern information through different releasable pools.

To compare the results for diagnosis of macular edema between Heidelberg retina tomography (HRT-II macular edema module) and optical coherence tomography (OCT).Two hundred and twelve eyes of 106 macular edema patients were diagnosed with fundus fluorescein angiography (FFA). HRT-II was used to obtain Edema Index and OCT was used to measure the retina thickness in the fovea. The results were compared with FFA.As FFA for gold standard, we compared with other diagnosis method. With regard to the diagnosis of macular edema by OCT, the Kappa value was 0.553, the odds ratio (OR) was 8.519. The Kappa value of HRT-II was 0.403 and OR was 3.210. In two groups of patients with and without macular edema, which were diagnosed by FFA, the difference of Macular edema Index P assayed by HRT-II between these two groups was significant (P = 0.00); while the difference of fovea retina thickness P assayed by OCT between these two groups was significant, too (P = 0.00). The best critical value of E was 2.00 and the ROC curve's area was 0.673 in the detection of macular edema by HRT-II. The best critical value of retina thickness for the diagnosis of macular edema was 170 microm and the ROC curve's area was 0.774 in the detection of macular edema by OCT.In regard to the diagnosis of macular edema, the sensitivity of HRT-II is better than that from OCT, with a lower false-negative result. However, HRT-II has a relatively low specialty with a higher false- positive result. As for the localization of macular edema, HRT-II has its advantage. Compared with FFA, the consistence of OCT for the diagnosis of macular edema is better than that of HRT-II. We can conclude from the OR value that OCT has greater influence than HRT-II in the diagnosis of macular edema. In addition, as for the diagnosis and different diagnosis, the clinical value of OCT is higher than that of HRT-II. Combination of these two different diagnostic methods might provide an accurate quantitative analysis of macular edema.

Ca2+ release from the endoplasmic reticulum (ER) is an integral component of neuronal Ca2+ signaling. The present study is to investigate properties of local Ca2+ release events in superior cervical ganglion (SCG) neurons.Primary cultured SCG neurons were prepared from neonatal rats (P3-P7). Low concentration of caffeine was used to induce Ca2+ release from the ER Ca2+ store, and intracellular Ca2+ was recorded by high-resolution line scan confocal imaging and the Ca2+ indicator Fluo-4.Two populations of local Ca2+ release events with distinct temporal characteristics were evoked by 1.5 mmol/L caffeine near the surface membrane in the soma and the neurites of SCG neurons. Brief events similar to classic Ca2+ sparks lasted a few hundreds of milliseconds, whereas long-lasting events displayed duration up to tens of seconds. Typical somatic and neurite sparks were of 0.3- and 0.52-fold increase in local Fluo-4 fluorescence, respectively. Typical Ca2+ glows were brighter (deltaF/F0 approximately 0.6), but were highly confined in space. The half maximum of full duration of neurite sparks was much longer than those in the soma (685 vs 381 ms).Co-existence of Ca2+ sparks and Ca2+ glows in SCG neurons indicates distinctive local regulation of Ca2+ release kinetics. The local Ca2+ signals of variable, site-specific temporal length may bear important implications in encoding a 'memory' of the trigger signal.

To analyse the pathogen of child patients with influenza in Tianjin area.The influenza virus isolation was performed by MDCK cells and embryonated eggs. The identification of the isolates was carried out with hemagglutination (HA) and hemagglutination inhibition (HI) tests.Two hundred and thirty-eight throat swab specimens from children with influenza-like illness were collected in Tianjin area from Oct. 2001 to Mar. 2002 and 64 strains (26.9%) of influenza virus were isolated. Data showed that there were 42 strains (65.6%) of A (H3N2) subtype, 13 strains (20.3%) of A (H1N1) subtype and 9 strains (14.1%) of B type in these positive isolates. All the isolated viruses grew very well in MDCK cells and hemagglutinated with human "O" red blood cells, and most (62/64 strains) of them were able to multiply in embryonated chick eggs. However, there were only 3 isolates with HA positive in inoculating embryonated eggs with the specimens. Meanwhile, it was revealed that out of 55 strains of A type viruses, 53 strains (96.4%) were from O to D phase, 2 strain of A (H3N2) were D phase characters and all B type isolated viruses being D phase properties.There were three endemic types of influenza viruses-A (H3N2), A (H1N1) and B type in Tianjin area, with A, the main type.

The title compound, (p-MeC6H4)2NC6H4CH=NNPh2 or C33H29N3, was synthesized by the reaction of 4-(di-p-tolyl­amino)benzaldehyde and 1,1-diphenyl­hydrazine. The mol­ecule is the trans isomer with respect to the hydrazone double bond. The central NC6H4CH=N—N fragment is planar within 0.11 A. The planes of the p-tolyl rings and one of the hydrazone phenyl rings form substantial dihedral angles (>60°) with the central plane of the mol­ecule, whereas the second hydrazone phenyl ring is much closer to the central plane, the dihedral angle being 21.7 (3)°.

The title compound, C37H33N, was synthesized by the Wittig–Horner reaction of 4-(N,N-dibenzyl­amino)-2-methyl­benz­aldehyde and the phospho­nate carbanion, derived from 1,1-diphenyl-3-chloro­propyl­ene and triethyl phosphite by the Arbuzov reaction. The butadiene fragment has a planar cisoid conformation, while the two benzyl fragments are almost parallel to each other, forming a dihedral angle of 9.8 (2)°.

The title compound, C31H29N or PhCH2(Et)NC6H4CH=CHCH=CPh2, was synthesized by the Wittig–Horner reaction between 4-(N-benzyl-N-eth­yl)amino­benzaldehyde and the phospho­nate carbanion, derived from 1,1-diphenyl-3-chloro­propyl­ene and triethyl phosphite by the Arbuzov reaction. The butadiene fragment has a planar transoid conformation.

The title compound, C36H31N, was synthesized by the Wittig reaction of 1,1-diphenyl-3-cholopropyl­ene and 4-[N,N-bis­(4-methyl­phen­yl)amino]benzaldehyde. The butadiene structure has a planar transoid conformation.