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The main issues that limit the large-scale application of TiO2 in photocatalysis is its low utilization of solar energy and high recombination rate of photogenerated charges. To overcome these limitations, a type II WO3·H2O/TiO2 heterojunction has been prepared via a one-step mild hydrothermal method that uses Na2WO4·2H2O and P25 as the starting materials and proceeds at 150°C without requiring any post-heat treatment for crystallization, special solvents or additives. The XRD and HRTEM results show that the prepared powders were composed of orthorhombic WO3·H2O and TiO2, and demonstrate the existence of the WO3·H2O/TiO2 heterojunctions. The photocatalytic activity of the as-prepared WO3·H2O/TiO2 heterojunction powders was investigated by using the degradation of phenol. The WO3·H2O/TiO2 heterojunction powders exhibited the best photocatalytic performance when the nominal W/Ti ratio was 6.57%, and showed better photocatalytic performance than commercial P25 and orthorhombic WO3·H2O.

A Co-catalyzed coupling of 3-(2-isocyanoethyl)indoles with organic azides in pure water for accessing spiroindolenine derivatives was developed. This strategy features mild reaction conditions, high atom-economy, excellent yields, wide substrate scopes, and broad functional group tolerance. The products were obtained simply by sequential operation involving extraction, concentration, precipitation, and filtration, without tedious column chromatography. More importantly, the aqueous catalytic system could be recycled at least ten times without reducing the catalytic activity. The strategy provides a green and efficient method for the construction of spiroindolenine derivatives.

An efficient cascade reaction of tryptamine-derived isocyanides with C,N-cyclic azomethine imines is described. The polycyclic pyrrolo[2,3- c ]quinoline derivatives, which benefited from rearrangement process driven by hydrogen bonding, could be directly assembled in moderate to good yields (40-87%) under metal-free and mild conditions. This transformation involved four new heterocyclic rings formations and uniquely, ring opening of indole as well as ring expansion of C,N-cyclic azomethine imine. Both experimental and DFT studies provided guidance on the in-depth insight into the reaction pathways and hydrogen bonding was identified to lower the free energy barrier in transition states. This work constitutes a rare example of tryptamine-derived isocyanide-based cascade reactions, and potentially could be a powerful synthetic strategy for accessing polycyclic analogues involved in natural products.

In this paper, synthesis of polysubstituted maleimides was described via cascade reaction of isocyanides and α-diazoketones. This strategy features readily available substrates, high atom-economy and metal-free conditions. A variety of valuable polysubstituted maleimides are assembled in good yields.

A one-step cascade reaction of tryptamine-derived isocyanides with in situ generated nitrile oxides for the synthesis of fused spiroindolines was described. The desired products could be efficiently synthesized in moderate to good yields (42-87%). The protocol features mild conditions, wide substrate scope, and high efficiency.

A Co-catalyzed cyclization reaction of isocyanides, azides, and amines to access quinazoline derivatives was described. This protocol features a high atom economy, mild reaction conditions, excellent yields, and a broad substrate scope. This cascade reaction involved three or four C-N bonds and the formation of one or two rings. The quinazolin-4(H)-imines obtained are proven to be versatile intermediates for further valuable transformations. It was also found that the cobalt catalyst could be isolated from the reaction mixture and reused.

Treatment of olefinic amides with N-bromosuccinimide (NBS) in water is reported. Monobromobenzoxazines were mainly formed at room temperature, while at 80 °C multibromobenzoxazines were preferentially generated. Mechanism studies showed that the reaction might proceed via a cascade of electrophilic addition at the C=C bond followed by electrophilic substitution at the aromatic ring. No additives are required in this protocol.

With people's increasing demands for the improvement of air quality and quality of life, the demand for new decorative materials with air purification function will be increasing. This study is based on a life cycle assessment (LCA)-based approach to develop a list of resources, energy consumption and pollutant emissions in the life cycle of typical visible light photocatalytic liquid products, to calculate the important environmental impact of visible light photocatalytic liquid products, and to analyze and identify the critical stages affecting environmental performance of product, to guide the selection of green buildings and the development of ecological building materials. The results show that, for the purpose of visible light photocatalytic liquid, the global warming potential is 40.97kgCO2 equivalent/t, the abiotic depletion potential is 9.34×10-5kgSb equivalent/t, the respiratory inorganic index is 7.88×10-2kgPM2.5 equivalent/t, and the eutrophication is 4.13×10-2kgPO43-equivalent/t, acidification effect is 0.34kgSO2 equivalent/t; and the environmental impact in the product life cycle for the purpose of this study are mainly resulted from energy use, and transport process represents the main stage of eutrophication.

An efficient and mild visible-light-enabled reaction involving the oxidative ring expansion of indoles with amidines in the aqueous phase at room temperature is developed. Benzo[1,3,5]triazocin-6(5H)-ones and quinazolinones were facilely obtained as the terminal products by using 2-substituted indoles and substituent-free indoles as substrates, respectively. This protocol features mild conditions, excellent functional group tolerance, and moderate to good yields.

A novel heteroannulation reaction between α,β-alkynic hydrazones and potassium thiocyanate has been developed for the synthesis of N-iminoisothiazolium ylides. The transformation features wide substrate scope, functional tolerance, and easy operation. This investigation involves a [4 + 1]-type cycloaddition reaction and C-S/S-N bond formation under transition-metal-free conditions. The application of this transformation to the gram-scale preparation of the N-imide ylide is also accomplished.

In this paper, synthesis of polysubstituted maleimides was described

Stable TiO2aqueous dispersion with an averaged secondary particle size of about 10 nm was achieved by using commercially available dispersant Di-7N. The stability of the dispersion was measured by Zeta-potential test. And the results showed that the optimal mass fraction of Di-7N was 12 wt%. The adsorption mechanism examined by FTIR analysis indicates that the carboxylate groups in Di-7N is absorbed on the surface of nano-TiO2particles and the adsorbed structure is proposed to be bidentate chelating.

Copper-catalyzed synthesis of 2-arylquinazolin-4-amines from readily available 2-arylindoles and TMSN3 has been developed. The mechanism study shows that the domino reaction may involve a free radical diazidation, denitrogenation, intramolecular cyclization and ring expansion sequence.

A new route for the preparation of benzo[1,5]diazocines from indoles and enaminone analogues is described. This protocol features easily available substrates, mild reaction conditions, high atom economy, environmentally friendly oxidants and site-selectivity. In addition, a plausible mechanism involving a cascade of copper-catalyzed oxidation/intermolecular cyclization/oxygen-participated intramolecular ring-opening is suggested.

An efficient method for the modular synthesis of various pyrimidine derivatives by means of the reactions of ketones, aldehydes, or esters with amidines in the presence of an in situ prepared recyclable iron(II)-complex was developed. This operationally simple reaction proceeded with broad functional group tolerance in a regioselective manner via a remarkable unactivated β-C-H bond functionalization. Control experiments were performed to gain deep understanding of the mechanism, and the reactions are likely to proceed through a designed TEMPO complexation/enamine addition/transient α-occupation/β-TEMPO elimination/cyclization sequence.

In this study, the effects of powder mixed method, sintering temperature, and the additive amount of the conductive phase on the dielectric loss tangent and permittivity constant of AlN/Mo composite ceramics were investigated. All the ceramic samples were prepared by spark plasma sintering (SPS). AlN composite ceramics with additional 10 vol% Mo sintered at 1400 °C holding for 5 min exhibit the best dielectric loss tangent, which is greater than 0.23. AlN/Mo ceramics with additional 20 vol% Mo become conductive, with the resistivity of 0.05–0.06 Ω·m. High-energy ball milling is better than magnetic stirring powder mixing method. In addition, the additive Mo and lower sintering temperature lead to a better property with the increase in the electromagnetic wave frequency range of 1 × 103–1 × 106 Hz.

An efficient metal-free dearomatization of indoles with α-bromohydrazones is reported. Various fused indoline heterocycles, which are potentially biologically active, were achieved in good yields (up to 94%) under mild conditions. A systematic study on electronic- and steric effects of substrate and reagents revealed that they have great influence upon the reaction. Based on this, the scope of indoles and α-bromohydrazones was widely exploited.

Yellow colored anatase Fe/N co-doped TiO2powders have been successfully synthesized by one step hydrothermal method at a lower temperature. The grain size was about 10 nm and the specific surface area of the powders ranged from 160 to 166 m2/g. The light absorption of Fe/N co-doped TiO2powders was enhanced in the visible light region of 400~500 nm and a new absorption peak at about 470 nm appeared when the Fe/Ti ratio exceeded 0.5%. The visible light photoactivity of Fe/N co-doped TiO2powders has been greatly improved than that of un-doped TiO2powders under visible light irradiation.

TiO2 thin films were prepared on SiO2-coated glass substrates using sols deriving from high concentration titanyl sulfate solution by the spin-coating technique. The calcined films were characterized by X-ray diffraction, UV-Vis spectroscopy, scanning electron microscopy. The film exhibited high transmittance in the visible light region and high absorption in the ultraviolet region. The contact angle of SiO2/TiO2 decreased to below 5° under 30 min of UV light irradiation and can sustain for 1 weeks.

Traffic rule is set to enable the safety and efficiency of the traffic. This paper takes the keep-right-except-to-pass rule as the research object. A three-lane cellular automaton model is proposed to simulate traffic flow. Through computer simulating, we analyze the relationships among traffic flow, overtaking ratio, average speed and density. The result shows that the rule although can increase the traffic flow and the average speed, the effect is not very evident, while this rule instead can increase driving safety in a large scale.

In this study, we have investigated how the dielectric loss tangent and permittivity of AlN ceramics are affected by factors such as powder mixing methods, milling time, sintering temperature, and the addition of a second conductive phase. All ceramic samples were prepared by spark plasma sintering (SPS) under a pressure of 30 MPa. AlN composite ceramics sintered with 30wt%–40wt% SiC at 1600°C for 5 min exhibited the best dielectric loss tangent, which is greater than 0.3. In addition to AlN and β-SiC, the samples also contained 2H-SiC and Fe5Si3, as detected by X-ray difraction (XRD). The relative densities of the sintered ceramics were higher than 93%. Experimental results indicate that nano-SiC has a strong capability of absorbing electromagnetic waves. The dielectric constant and dielectric loss of AlN-SiC ceramics with the same content of SiC decreased as the frequency of electromagnetic waves increased from 1 kHz to 1 MHz.

Cell-penetrating peptides provide a unique platform to create a new generation of cancer therapeutics with enhanced efficacy and diminished toxicity. In our study, enhanced expression of toll-like receptor 2 (TLR2) was observed in acute myeloid leukemia (AML) cells. Screening of a phage display peptide library using Biopanning and Rapid Analysis of Selective Interactive Ligands (BRASIL) identified a TLR2-binding peptide motif, Pep2. We show that the TLR2-binding peptide motif targeted and penetrated into leukemia cells in a TLR2-dependent manner. Moreover, a synthetic, chimeric peptide composed of the TLR2-binding motif linked to a programmed cell death-inducing sequence, D(KLAKLAK)2, induced apoptosis in AML cells with high TLR2 expression (TLR2(high)) but not in chronic myeloid leukemia (CML) cells with low TLR2 expression (TLR2(low)). The antileukemia activity of this chimeric peptide was confirmed in leukemia patient samples and an animal model of myeloid leukemia, as the development of leukemia was significantly delayed in mice with TLR2(high) AML compared to TLR2(low) CML NOD/SCID mice. TUNEL assays on bone marrow tissue slices revealed that the chimerical peptide induced leukemia cell apoptosis in a TLR2-dependent manner. Together, our findings indicate that TLR2 is a potential therapeutic target for the prevention and treatment of AML, and the prototype, Pep2-D(KLAKLAK)2, is a promising drug candidate in this setting.

In the field of military communications, the SNR of speech signal is low because of the additive noise,. The two-level Wiener filter is adopted to analysis the noise characteristics. The DSP system architecture solutions are given out in this paper.The algorithms of the PSD mean module, Mel scale filter bank module, voice activity detection module and gain control module are introduced in detail. Finally, the application results are given out, which indicate that two Wiener filter can achieve better results, in short stationary noise environments when face the low SNR.

In order to realize the performance testing and fault diagnosis of communication devices in the Command and Control System, a testing system is proposed. In this paper, a novel communication protocol is developed to realize the communication between the host computer and lower computer of the testing system. As to the different functions of the testing system, the format and sense of the communication messages were introduced in detail. 15 kinds of messages were designed to complete the functions of the open and close of communication serial, data detection ports, the receive and transmission of detection data, the control of the I/O and so on. The communication protocol makes it possible to form the test path and achieve the test of different devices.

As to the speech signal processing problems under the complex voice environment, the characters of speech harmonic and the structure of voiced harmonic are discussed in this paper. In the third dimension frequency domain, quadratic Fourier transform algorithm based on logarithmic amplitude-frequency characteristics is used to propose the concept of the third dimension spectral harmonic ratio" by the behavior of the quasi-sinusoidal characteristics of the speech short-time Fourier spectrum slicing, which is cosider to be an important basis to discriminate speech activity detection. The concept of third dimension spectral harmonic ratio maks the speech signal as a special signal, and separate from the other noise signal completely. For voice noise outside the speech segment, it is no longer need to discuss its own characteristics and without the need for pre-processing to shield the noise accurately, which bring new ideas for the speech signal detection in the complex noise environment.

For the purpose of solving the problems, such as many kinds of C3I equipment signals to be test, complicated technology and technology fast updates, a test system based on flexible technology is proposed. In this system, the core technical cocept of systematize and developmental design is adopt. In this paper, the design ideas, software and hardware design and test diagnosis process are described in detail. The detection system based on flexible test achieves calling testing resources according to the different objects, interfaces conversion and signal conditioning. The system has good characteristics on flexibility, reliability, adaptability and expand [1-, which is of great significance for the equipment maintenance and support.

With the advent of the information age, the theory of network-centric operations come into beings. Network and network devices constitute the core of the C3I system which is the cornerstone of the network-centric operations. However, it is difficult to maintenance and support the C3I network devices for the reason of its specific features, such as its all kinds of models, wide geographical distribution, complex structure, highly reliability requirements and so on [. we propose a network device monitoring method to improve network equipment running reliability, real-time fault detection and save the utilization of network resources based on the existing method.

The wind load is always the dominant load of cooling tower due to its large size, complex geometry and thin-wall structure. At present, when computing the wind-induced response of the large-scale cooling tower, the wind pressure distribution is obtained based on code regulations, wind tunnel test or computational fluid dynamic (CFD) analysis, and then is imposed on the tower structure. However, such method fails to consider the change of the wind load with the deformation of cooling tower, which may result in error of the wind load. In this paper, the analysis of the large cooling tower based on the iterative method for wind pressure is studied, in which the advantages of CFD and finite element method (FEM) are combined in order to improve the accuracy. The comparative study of the results obtained from the code regulations and iterative method is conducted. The results show that with the increase of the mean wind speed, the difference between the methods becomes bigger. On the other hand, based on the design of experiment (DOE), an approximate model is built for the optimal design of the large-scale cooling tower by a two-level optimization strategy, which makes use of code-based design method and the proposed iterative method. The results of the numerical example demonstrate the feasibility and efficiency of the proposed method.

Analysis external characteristic of hydraulic torque converter by modeling and numerical simulation on a type of YJ series. Using a leafy row whole runner geometric model and sliding grid method of multiple flow area coupling algorithm to realize real-time transmission of flow parameters between impellers .Getting values of moment of force from pump & turbine in each iteration step through UDF used in model ,then input that to text file. Judging whether the result tends to be stable or not by analysis and calculation changes of the text data. Result shows that the leafy row whole runner geometric model has high accuracy and reliability from comparing data under different conditions with measured moment data.

C3I network equipments, with complex architecture, deal with quantities of information from the aspect of time and space, which makes them difficult to support. This paper adopts automatic test and diagnosis techniques, analog networking technique and active test method to satisfy the requirements of timeliness, intelligence and high precision in fault location. A virtual network environment is built to complete the network equipments’ test. It is significant to the complex network equipments’ test and diagnosis.

Silica-sol and activated carbon were used to prepare SiC whiskers by microwave heating. The effect of packing density of raw material powders on the morphologies of SiC whiskers has been investigated. It was argued that by decreasing the packing density of raw material powders, the growing space of the SiC whiskers increases and the morphologies of the whiskers changes from flexural to straight along with the increase in length. When the packing density was lower than 0.26 g/cm3, straight and dispersal SiC whiskers with high slenderness ratio could be obtained.

N-doped TiO2 powders have been prepared by solvothermal synthesis using TiCl3 aqueous solution as precursor. The as-synthesized powders are composed of anatase and rutile and show light-yellow in color. The grain size is ranged from 10.3 nm to 19.1 nm by Scherrer's method and the specific surface area is ranged from 21 m2/g to 122 m2/g. X-ray photoelectron spectroscopy (XPS) results indicate that N atoms have been doped into the lattice of TiO2. Ti-N bonding and radical groups such as ×OH were detected on the surface of the powders. The synthesized N-doped TiO2 powders shows excellent visible-light photocatalytic activities and their absorption edge have been red-shifted to 560 nm.

A new 2D photonic crystal microcavity is proposed based on the localized modulation and the model match technique. Structure of the new PC cavity is characterized in that several scatters are introduced into the edges of the L3 microcavities. The local field modulation method is applied in the new PC microcavity to optimize the cavity structure, and the quality factor Q and transmission T can be both improved after modulation. During the modulation process, Q and T of the new PC cavity represent an identical variation trend. The Q and T of the optimized PC cavity, with the simulation parameters confined in our work, reach to 240000 and 0.68 respectively.

Nanocrystalline W-doped TiO2 powders with different initial W/Ti ratio in starting materials have been prepared by hydrothermal method. The phase composition, morphologies, specific surface areas and the photocatalytic activities under visible light irradiation of the synthesized powders have been characterized. XRD identification reveals that the synthesized powders were composed of anatase. No rutile has been detected in the products. The specific surface area of the powders was ranged from 185 to 210 m2/g by BET measurement. The averaged grain size of the powders was calculated as about 12 nm by Scheller's method. Uniform size distribution and good crystallinity have been confirmed by TEM. UV-Vis spectra show that the absorption edges of the synthesized W-doped TiO2 powders with different nominal doping concentration of Wions have been red-shifted into visible light region, which suggests that the W ions have been doped into the lattice of TiO2. In our case, W-doped TiO2 with initial W/Ti atomic ratio of 1% in starting materials has the best photocatalytic activities when decompose the Methylblue in its aqueous solution, which is consistent with that of the theoretical results from our previous work.

Nanometer-sized β-SiC were synthesized by carbothermal reduction of silica sol with acetylene carbon black at 1600 °C for 2h. Three kinds (straight, bamboo-like, branch-like) of SiC nanowires were deposited on the graphite plate, while SiC particle agglomerates and nanowires were formed in the graphite crucible. All the nanowires were formed via VS mechanism through the reaction between gaseous SiO and CO produced from the process of carbothermal reduction.

Titanate nanotubes have been directly prepared by hydrothermally treating P25 powders in NaOH aqueous solution. Effect of calcination temperature on crystal phase, morphologies and specific surface area of the as-synthesized nanotubes has been investigated in detail. The Na2Ti3O7 tubular structure could be kept well even after calcination at 600 °C and began to transform to Na2Ti6O13 nanorods at around 645 °C. The specific surface area of the as-synthesized nanotubes was 200.6 m2/g and reached to the maximum of 347.9 m2/g after calcination at 300 °C and then decreased sharply with the further increase of the calcination temperature.

TiO2 thin film was prepared on soda lime glass by hydrolysis of Ti(OC4H9)4 in alcoholic solutions by sol-gel method combined with spin-coating and calcination different temperatures. Prepared samples were characterized by XRD, FESEM, and measurement of contact angles and transmittance. XRD identification reveals that the films are composed of anatase TiO2 when the annealing temperature was set at 450~550 oC. SiO2 layer was coated on the surface of the glass firstly to barrier the diffusing of sodium ions from the substrate. Light-induced superhydrophilicity of the TiO2 thin film has been investigated. To increase the illumination light intensity will decrease the water contact angle. The superhydrophilicity of the TiO2 thin film will disappear more slowly in the dark than that in the field of ultrasound.

The binding energy of anatase TiO2, in which the Ti was substituted by other transition metals in the 4th, 5th and 6th periods of the periodic system of the elements, has been calculated by using first principles method. The doping limits of V, Cr, Zr, Nb, Mo and W are 61.5%, 39.7%, 88.2%, 100.0%, 65.0%, and 63.2%, respectively predicted by the calculated binding energy, while the doping limits of other transition metals are much lower. So, these transition metals can easily be doped into the anatase structure theoretically while it is difficult for the others. And the band structure and density of states (DOS) of V, Cr, Zr, Nb, Mo and W doped anatase TiO2 have also been calculated and analyzed.

Yellowish (Fe, N)-doped nanocrystalline TiO2 powders have been prepared using TiOSO4, CO(NH2)2, Fe(NO3)3.9H2O and CN3H5.HCl as precursors by hydrothermal method. The as-synthesized powders were anatase in phase and the grain size was about 10 nm according to the TEM photos. The ratio of Fe/Ti is 2.2 at% and N/O is 0.8 at% respectively. TiO2 powders were mixed with organic silicon and acrylic syrup to test their antibacterial performance by the colony counting method. The results show that the sterilization ratio of E. coli by the heat-treated (Fe, N)-doped nanocrystalline TiO2 powders is reached up to 94.5% while that of the powders without any heat treatment is 91.1% by 8 hours-400 lux-Visible-light irradiation with humidity of 55% RH.