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Hexanitrostilbene plays an important role in aerospace and space technology because of its excellent chemical stability. However, carbon deposition during the explosion seriously affects its detonation performance. A newly parameterized reactive force field was used to simulate the decomposition behavior of nanometer aluminized hexanitrostilbene. Aluminum nanoparticles and the corresponding surface oxidized ones were mixtured with the hexanitrostilbene to build nanometer aluminized composites. The simulation results show that aluminum nanoparticles lead to an earlier decomposition of hexanitrostilbene in a new way. Aluminum nanoparticles follow diffusion oxidation theory in the heating. At high temperatures, Aluminum nanoparticle quickly splits and exposes active aluminum to participate in the reaction. The presence of oxide layer in surface oxidized aluminum nanoparticle is less attractive to oxygen, carbon and nitrogen atoms, and surface oxidized aluminum nanoparticle is difficult to split into small particles during ignition and detonation. Aluminum nanoparticles prevent the formation of larger carbon clusters and cause hydrogen and oxygen atoms escape from carbon clusters. This is the main reason for the increasing detonation pressure and energy outputs of nanometer aluminized Hexanitrostilbene. Adiabatic simulation shows that nanometer aluminized hexanitrostilbene decomposes faster and releases more energy than pure hexanitrostilbene. This work provides insights for the application of aluminized hexanitrostilbene composites in aerospace.

Based on triphenylamine as an electron donor and thiophene as a π-linker, Series P and A p-type sensitizers were designed to investigate the effects of the different acceptors on the properties of the sensitizers. The optimized molecular structures, electronic and optical properties were investigated by density functional theory (DFT) and time-dependent DFT (TD-DFT). The results showed that the properties of the dyes can be tuned by the introduction of the different electron-withdrawing groups to the N atom in the pyridinium acceptor. Compared with the synthesized Series P dyes used in p-type sensitizers, the properties of Series A dyes, except for two dyes that cannot be used as p-type sensitizers, are improved by means of modifying pyridinium acceptors. Due to the suitable electron-withdrawing ability of the hexafluorodiacetylamino group in its acceptor, A6 has the narrowest energy gap (1.90 eV), the largest driving force of hole injection (ΔGinj, −0.68 eV), the high light harvesting efficiency (LHE, 0.9984) and the smallest internal reorganization energy (λint, 5.05 kcal mol−1). Hence, A6 not only enhances electronic excitation, but also improves the reorganization energy. Importantly, A6 shows the largest red shift and the maximum integral values of the adsorption over the visible light, as well as the strongest adsorption energy (−74.80 kcal mol−1) on a NiO surface. Thus, A6 may be a promising sensitizer for the p-type dye-sensitized solar cells (DSSCs), and the acceptor of A6 may provide a new and easily accessible high performance acceptor for p-type sensitizers.

On the basis of thieno(3,2-b)thiophene and dithieno[3,2-b:2&prime, 3&prime, d]thiophene (T2 and T3 moieties) as &pi, linker, the A, D and S series dyes were designed to investigate the effect of the introducing N+ as an &ldquo, electron trap&rdquo, into T2 and T3 on the properties of the dyes. The optimized structures, electronic and optical properties were investigated by the density functional theory (DFT) and time-dependent DFT (TD-DFT). The results show that the properties of the dyes are sensitive to the N+ position in &pi, linkers. D series dyes with electron-withdrawing units located near the donor have better properties than the corresponding A series with the electron-withdrawing units located near the acceptor. For A and D series, the N+ modified dye named T2N+1-d displays the largest red shift of the UV&ndash, vis absorption, the maximum integral values of the adsorption-wavelength curves over the visible light, the highest light harvesting efficiency (LHE, 0.996), and the strongest adsorption energy (&minus, 44.33 kcal/mol). T2N+1-d also has a large driving force of hole injection (&Delta, Ginj, &minus, 0.74 eV), which results in a more efficient hole injection. Bearing a lengthier &pi, linker than T2N+1-d, the properties of T2N+1-s are further improved. T2N+1-d moiety or its increased conjugated derivatives may be a promising &pi, linker.

On the basis of triphenylamine as an electron donor with attachment of two –COOH anchoring groups and dicyanovinyl as acceptor, ten dyes with D-π-A structures were designed to investigate the effects of different π-linker groups on the properties of the sensitizers, especially the influence of the π-linkers containing nitrogen cation (N+). The optimized structures and electronic and optical properties were investigated by the density functional theory (DFT) and time-dependent DFT (TD-DFT). The results show that all the investigated dyes can be used as dye sensitizers for the p-type dye-sensitized solar cells (DSSCs) except one dye which contains two N+. The N+ modified dye (named S3-PZL1C) has narrow energy gap (2.02 eV), the best light-harvesting efficiency (LHE, 0.9974), and the smallest internal reorganization energy (λint = 7.00 kcal/mol). Importantly, S3-PZL1C displays the largest red shift of the UV-vis absorption, the maximum integral values of the adsorption-wavelength curves over the visible light (400~800 nm), and the strongest adsorption energy (− 66.84 kcal/mol) on NiO surface. In addition, S3-PZL1C not only enhances the electronic excitation but also improves the reorganization energy and charge separation. The intramolecular charge transfer towards the acceptor is sensitive to the N+ position in π-linkers. Therefore, the suitable introduction of N+ in dyes can improve the performance of the dyes, and the PZL1C moiety may be a promising π-linker for p-type DSSCs.

Excimer laser is the current mainstream source of international semiconductor lithography. The stable operation of the laser system directly affects the working efficiency of the semiconductor lithography machine, so it is very important to optimize the laser system. The buffer gas commonly used in ArF excimer laser systems is He, Ne. In the early years, Shinjin Nagai and Mieko Ohwa have studied the output characteristics of the system when using He or Ne as a buffer gas from the aspect of pump efficiency and gain coefficient, and pointed out that using Ne instead of He has no obvious advantages in terms of efficiency. However, when Ne is used as the buffer gas, the reaction between Ne and electrons is more complicated. In addition to direct ionization and excitation reactions, it also contains a large amount of step ionization and secondary ionization, which releases free electrons. The stability of the system is improved, when Ne is used as the buffer gas. The ArF excimer laser system discharge characteristics in different buffer gases are analyzed based on fluid model in the paper. The role of photoionization is discussed. The simulation results show that the width of the electron depletion layer and the cathode sheath are both smaller, and the discharge stability is higher when Ne is used as the buffer gas. The expansion of the discharge region is accelerated and the threshold voltage of the discharge is reduced by adding Xe into Ne to trigger photoionization. The excimer laser discharge process is very complicated and is affected by many factors. Only two factors of the buffer gas and the photoionization process are studied in this paper. The simulation model will be extended from one-dimensional case to two-dimensional case in the future, and multiple physical factors of the ArF excimer laser system will be considered.

To understand the hydatidosis prevalence in 6- to 12-year-old children in southern Xinjiang Uygur Autonomous Region and provide scientific basis for formulation of control measures.One primary school was selected from each of the pastoral area, pastoral-agricultural area, agricultural area, and township area in 42 counties （cities） of southern Xinjiang, using the stratified sampling method. With the consent of their parents, B ultrasonic abdominal scan and venous blood collection were performed on all the children （6-12 years） in the selected schools. Serum level of echinococcus antibody IgG was determined by ELISA. Hydatidosis prevalence and the serum level of IgG in these children were analyzed.A total of 80 429 children were examined from 168 primary schools. B ultrasonic scan revealed hydatidosis in 9 children （0.01%）, comprising 3 cases in Kezhou, 2 in Aksu, 2 in Bazhou, and 2 in Kashi. ELISA results showed that 4 189 children were positive for serum IgG, with a positive rate of 5.21%. The positive rate was highest in Kashi （8.41%, 2 143/25 495）, followed by Aksu （5.69%, 913/16 051）, with significant difference between different areas （χ2=977.303， P0.01）. The positive rate was lowest in 6-year children （2.13%, 44/2 065） and highest in 11-year children （5.68%, 822/14 462） （χ2=48.221, P0.01）. In addition, the positive rate was highest in Uighur children（5.19%, 3 899/75 115）, followed by Mongolian children （4.27%, 68/1 592）, with no significant difference between ethnic groups （χ2=4.072, P0.05）. Among the children of residents, children with a nomadic lifestyle, and children settled in winter and living in a nomadic lifestyle in summer, hydatidosis occurred in 7 residents and 2 children who settled in winter and living in a nomadic lifestyle in summer; and the positive rate of serum antibody was 5.45% （184/77 512）, 2.97% （3/101）, 0.07% （2/2 816）, respectively（χ2=148.609, P0.01）.There is a low hydatidosis prevalence in 6- to 12-year-old children in southern Xinjiang, but the positive rate of serum echinococcus IgG in kashgar region, Uighur ethnicity, and children of the resident group are relatively high.

A narrow-linewidth ArF excimer laser using a compound cavity with two oscillators but the same discharge chamber is developed. Methods for the locking of narrowband laser modes in long cavity length and insufficient mode competition are introduced.

[Abstract]To analyze the situation of echinococcosis surgerical cases in Xinjiang Uygur Autonomous Region from 2005 to 2013.The surgery cases of echinococcosis in Xinjiang from 2005 to 2013 were collected, and analyzed with SPSS 17.0 and Epi Info 3.5.3 software.A total of 8 639 hydatid disease cases were reported during 2005-2013 from 94 counties (cities and districts) of 14 prefectures (municipalities) in the Region. The average number of annual operation cases were 960 cases (8,639/9 years), and the annual incidence was 4.40/100,000 (960/21.81 million). 82.8% (7,152/8,639) of report cases came from northern Xinjiang area with an incidence of 7.59/100,000, and 17.2% (1,487/8,639) distributed in southern Xinjiang area with an incidence of 1.58/100,000. There were 373 cases (4.4%, 373/8,639) reported in 2005, and increased to 1434 cases (16.5% 1,434/8,639) in 2013 (P0.05). The cases mainly distributed in Yili Kazak Autonomous Prefecture (2,028 cases), Tarbagatai Prefecture (1,218 cases), Changji Hui Autonomous Prefecture (1,179 cases), and Urumqi City (1,128 cases) of the northern Xinjiang area. There were 4,557 male (52.8%, 4,557/8,639) and 4 082 famale patients (47.3%, 4,082/8,639)(P0.05). The age distribution showed a single-peak curve, and more patients concentrated in the age group of 31-40 years, accounting for 26.2% (2,265/8,639). Among 8,639 cases, farmers accounted for 47.9% (4 134/8 639).The nunber of surgical cases of echinococcosis increases every year in Xinjiang since 2005, and the distribution of the disease shows a trend from the agricultural and pastoral areas to the towns.

We report a blue-lines pumped femtosecond Kerr-lens mode-locked Cr:LiSGaF laser based on a tight-focusing geometry. With a combination of 488, 476 and 458 nm lines as a pump source, 58 fs pulses centered at 845 nm were generated. The average output power is 30 mW, and time–band product is 0.331, assuming a sec h2 pulse shape. Neither acousto-modulator nor physical aperture or slit were used in this cavity.

We demonstrate a femtosecond Kerr-lens mode-locked Cr:LiSGaF laser that based on a compact cavity geometry. For the first time to our knowledge, with a combination of 488-, 476- and 458-nm lines from Argon-ion laser as a pump source, 58-fs pulses centered at 845 nm were generated. The average output power is 30 mW, and the time-band product is 0.331, assuming a sech 2 pulse shape. Neither Acousto-modulator nor physical aperture or slit were used in this cavity to start and sustain the Kerr-lens mode-locking operation.