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The geometrical and electronic properties of B-doped ZnO monolayer with the concentrations of 12.5% and 25% have been calculated using the first-principles method. B-doped ZnO monolayer leads to the structural distortion around the doped atoms compared with the pure ZnO sheet. The B-B pair or two B-B pairs doped ZnO monolayer present nonmagnetic metal.

Microwave dielectric ceramics with a nominal composition of 0.95MgTiO3-0.05CaTiO3-xPrAlO3(x=0-0.015) were prepared by conventional solid-state sintering. The phase composition, microstructure and dielectric properties were characterized by X-ray diffractometer, scanning electron microscope and vector network analyzer, respectively. A two-phase system with major MgTiO3phase and minor CaTiO3phase was detected. With increasing content of PrAlO3, the grain size of the obtained ceramics decreased; the dielectric constant and quality factor increased first and then decreased. The temperature coefficient of resonant frequency decreased after PrAlO3was doped, but with more PrAlO3doped it will increase. The obtained 0.95MgTiO3-0.05CaTiO3ceramic doped by PrAlO3with x=0.0075 presented the best performance with εr=19.04, Q·f=42400 GHz and τf=-19.40 ppm/°C.

The Ho2Fe17-xSix (x=0.0, 0.1, 0.2, 0.3) alloys were prepared by arc melting and high energy ball milling method. The influence of the Si substitution on phase structure, morphology and electromagnetic parameters were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and vector network analyzer (VNA), respectively. The results show that the Ho-Fe-Si particles are flaky after the ball milling. The minimum absorption peak frequency shifts towards a lower frequency region with the increasing of Si content. The minimum RL of Ho2Fe16.7Si0.3 reaches-42.96 dB at 9.76 GHz, and the frequency bandwidth of R

The smooth spherical BiOCl photocatalyst was synthesized successfully by a facile solvothermal method and further characterized by X-ray diffraction, scanning electron microscopy, energy dispersive spectrometer and UV-Vis diffuse reflectance spectra techniques. The photocatalytic activity of as-prepared photoctalyst was evaluated by the degradation of Rhodamine B (RhB) under visible light irradiation (λ>420 nm). The results showed that the BiOCl with smooth spherical morphology exhibits an excellent photocatalytic activity and stability. RhB was thoroughly degraded after 60 min of visible light irradiation.

In this paper, the influences of sintering conditions on the phase transformation, microstructure, bulk density, bending strength, coefficient of thermal expansion, and dielectric properties of Li2O-Al2O3-SiO2 glass-ceramic were investigated. Conventional melt-quenching method was used to synthesize this glass-ceramic. Scanning electron microscopy, X-ray diffractometer and differential thermal analysis were employed to study this material. The XRD data show that Li2OAl2O37.5SiO2 is the main crystalline phase of this glass-ceramic. ZrO2 and CaMgSi2O6 are the two other phases in this glass-ceramic. The increasing sintering temperature and soaking time affect the phase composition obviously, which lead to the obvious variations of microstructure, mechanical, dielectric and thermal properties of this glass-ceramic. Sintering temperature and time play a key role in the sintering of Li2O-Al2O3-SiO2 glass-ceramic. The sample sintered at 800 °C for 30 min showed good microstructure, low sintering temperature of 800 °C, high density of ~2.6 g/cm3, excellent dielectric properties (εr: ~6.9, tan δ: ~2*10-3), good bending strength of 143 MPa and adjustable CTE from 1.1 to 2.7 *10-6 K-1 close that of silicon. These results mean that the obtained LAS glass-ceramic can be used in the application of LTCC substrate, especially, the manufacture of the substrate of silicon.

Magnetic metal silica submicrospheres were produced from silica coated on magnetic nanoparticles using well controlled hydrothermalled method and were characterized by TEM, XRD, FTIR, XPS. The well-designed mesoporous magnetic metal silciate had a large specific area, high magnetization. Firstly, SiO2-coated maghemite (Fe3O4@SiO2 composites) were synthesized by an sol-gel method, in which the iron ferrous chloride as well as TEOS acted as the precursor for maghemite and SiO2, respectively. The Fe3O4@SiO2 composites revealed a core-shell structure, Then, Fe3O4@SiO2/X3Si2O5(OH)4(X = Ni, Cu, Zn) was obtained by hydrothermalled with metal chloride. The resulting composites show not only a magnetic response to an externally applied magnetic field, but also can be a good adsorbent for bovine hemoglobin in the ambient temperature.

In order to analyze the dynamic response of asphalt pavement under vehicle load, the random characteristic of pavement roughness was considered and the vehicle was simplified into 1/2 model with four freedom degrees when establishing the dynamic load model. Then the sequence of the random dynamic load coefficient was obtained by developing a MATLAB program based on the incremental Newmark-β method. Based on the plane strain assumption, a two-dimensional layered finite element model of asphalt pavement was established by ABAQUS software. Then the dynamic load coefficient was used to modify tire pressure that would be applied on the ABAQUS model. Then dynamic response rule of the model and how it was effected by vehicle speed were studied under random load. The results show that under the condition of random load, dynamic response of the pavement structure exhibiting a fluctuation trend as vehicle speed increases and the dynamic response characteristics of each point is different.

The aim of this work is to reduce the residual stress in cured SU-8 Photoresist layer by vibration stress relief (VSR) method. The vibration device was designed according to the results of the ANSYS modal simulation, which was used for the thin film VSR. Meanwhile, some important influencing factors, such as the excitation current and the vibration time, have been discussed. The residual stress in the SU-8 layer was measured by profile method, and the values of residual stresses in the SU-8 layer before and after VSR were compared. The experimental results show that residual stress in SU-8 layer can be effectively eliminated or homogenized by VSR if the proper vibration parameters were chosen in the experiment.

The purpose of this work is to study the mechanical characteristics of the silicon nitride(SiNx) thin films prepared by PECVD technique, some researches as follows were carried out. First, the SiNx thin films were deposited on the two different substrates. Then, the atomic force microscope (AFM) was adopted to test the surface quality of the SiNxfilms, and the scanning electron microscope (SEM) was used to test the section morphology of the SiNxthin films. Finally, the rotating beam structures was applied to measure the residual stress in the SiNx films. The SiNxthin films with low stress can be fabricated through PECVD, in which the surface roughness values(Ra) are 1.261 nm and 2.383nm, and the residual stress is 43.5 kPa. Therefore, the SiNxthin films deposited by PECVD are suitable for the preparation of device dielectric films in MEMS.

Cd2Ge2O6 nanowires have been synthesized via a simple and facile hydrothermal route using GeO2 and CdO as the source materials with the surfactant. The structure and morphology of the Cd2Ge2O6 nanowires were fully analyzed by field emission scanning electron microscope (FESEM) and HRTEM. With a focused electron beam irradiation, the Cd2Ge2O6 nanowire became unstable and tended to heavily destroyed under a long time irradiation. Using the TEM-STM holder, electrical properties of an individual Cd2Ge2O6 nanowire has been measured and the obtained I-V curve demonstrated the semiconductor property.

This paper studied protective atmosphere furnace used in the thermoforming production line of ultra high strength steel plate, simulation and analysis for the key technologies and structure of furnace have been made, and two patents formed (ZL201320006066.2, ZL201320007455.7). 1, Research and develop the structure of roller and its ends for heating furnace; 2, the heating process of furnace has analyzed and calculated, the protective atmosphere furnace developed fully meet the requirements of high-strength steel thermo-forming production line; 3, the mixture of high-purity nitrogen and dissociated methanol gas was used as the protect atmosphere, It has been verified the effect of protective atmosphere system is good. The high-strength steel plate protective atmosphere furnaces and production lines, we developed, has independent intellectual property rights, the properties and surface quality of thermoformed steel plate are good.

In order to adapt to the development trend in current vocational education, we developed a multi-functional hydraulic test bench for mechatronics teaching practice. The component structure and functional features of the test bench was introduced in this paper and the application to vocational education was proved to be effective. Practice shows that the bench not only provides students with good experimental conditions close to the actual production and inspires learning enthusiasm and innovation consciousness of the students, but also provides teachers with a platform for scientific research, improves the utilization value of equipment.

In this paper, three-dimensional integration framework of landslide monitoring data was proposed in the idea of mineral point-source information system and the WebGIS technology based on ActiveX. Seamless integration of data related to landslide monitoring,such as basic geographic data, geological survey data and sensor data was realized. In this process, program algorithm automatically handled method and visual interpretation in three-dimensional environment were used to improve the accuracy of landslide monitoring data. Furthermore，the suitability of landslide monitoring database was improved by separating landslide monitoring data from prediction mathematical model. All this provides the excellent basis for the stability evaluation and forecast of landslide. The monitoringproject of HuangTuPo landslide in Three Gorges Reservoir of China was taken as example to verify feasibility of the method.

Aluminum alloy A6061 and mild steel Q235 was welded using resistance spot welding with an interlayer of AlCu28. The mechanical properties of the joint were investigated; the effects of various welding parameters on nugget diameter and tensile shear load of the joints were systematically discussed. The results reveal that it is effective to weld aluminum alloy and mild steel using resistance spot welding with an interlayer of AlCu28.

In order to achieve the sided different effects and the function of UV shading of the three layers jacquard curtain fabric, we used two sets of the same common yarns as the warps, 2 groups of wefts in the front while 2 groups of wefts in the opposite and a group of TiO2 polyester weft which plays the role of UV-shading. The fabric’s wefts arrangement ratio is 1:1:1:1:1. There are four kinds of weaves in the front and five in the opposite (seeing from the reverse side), then in overlaying the four kinds in the front with the five kinds in the opposite we can get 20 kinds of weaves. By integrating shading cloth and curtains with two-sides-different effects together, in the end, the three layers jacquard curtain fabric which has two-sides-different effects and UV-shading function is achieved.

Pd-Cu-Ce composite membrane was prepared using an electroless plating technique. The effects of temperature and pressure on permeation were studied. The resistance to sulfidation was examined by exposing alloys to simulated syngas containing a combined gas of H2 and H2S. The alloys showed sings of slight sufidation at the 0.1% H2S exposure level.

In order to weave the double face jacquard fabric with pattern effect at the same time increasing warming function of the jacquard, this paper added far infrared polyester as extra weft to stitch the face and back layers. Combining the basic structure design of the double face jacquard fabric, three-layer weave with extra weft stitching could be done. By this method extra weft could be hidden in the form of surface layer floats covering stitching intersection points so as to have heat retention effect and unique appearance of reversible jacquard isn’t impacted. In addition, the weft yarns used to produce the face and back layers were silk and wool, and far infrared polyester was hidden in the inside of the fabric as extra weft which ensured the jacquard being good for skin. Empirical results show that the method achieves good decorative property and warming function of the double face jacquard fabric with pattern effect, and provides reference and direction for the design of digital jacquard fabric.

Objective: To study the chemical constituents from the root and stem of Zanthoxylum avicennae. Method: The constituents were separated by column chromatography, and their structures were elucidated by spectroscopic data analyses. Result: Fourteen compounds were isolated from the EtOAc extract and identified as Avicennin (1), Xanthoxyletin (2), Luvangetin (3), Norchelerythrine (4), Diisobutyl phthalate (5), β-amyrin (6), Lupeol (7), Chelerythrine (8), Dictamine (9), γ-fagarine (10) and Skimmianine (11), Sesamin (12) Syringaresinol (13) and P-hydroxybenzoic acid (14). Conclusion: The compounds 2, 4, 5, 6, 7, 12 and 14 were obtained from this plant for the first time.

Prone to low temperature cracking of asphalt pavement problems in cold areas, testing BBR on 70# base asphalt and 4 kinds of different dosage of SBS modified asphalt, testing TSRST on their mixture to appraisal the low temperature performance of SBS modified asphalt mixture. Results show that compared with the temperature stress of internal cracks of base asphalt and SBS modified asphalt mixture not rise significantly. But the stress of SBS asphalt mixture growing slow and the temperature of cracking reduce obviously; it means the low temperature performance improved. This shows that SBS improves the toughness and reduced the modulus of asphalt mixture in low temperature, rather than increasing the tensile strength of mixture specimens.

Copper chalcogenide nanoparticles (NPs) represent a promising material for solar energy conversion and electrical charge storage. We showed that aqueous synthesis of high quality monodispersed high-chalcocite Cu2S NPs is possible. Here, different thioglycolic acid (TGA) concentrations were employed in studies made to investigate the effects of stabilities ratio on particle morphology. It was found that the stabilizes concentration plays a key role in the synthesis of Cu2S NPs, the reaction rate is fast at low concentrations of TGA, and the size range is lager, while flower-like cluster with sizes of 30 nm were formed at high concentrations of TGA. Rapid availability of our results will provide valuable insight into the controlled growth of aqueous dispersions of ternary copper chalcogenide NPs, stimulating further studies of these materials in green energy conversion technologies and drug delivery applications.

This paper analyzed and researched physical education curriculum evaluation system according to the principle of computer evaluation technique. The first part introduced the physical education curriculum evaluation system this thesis designed the function of the system. The second part of the paper established the mathematical model of the teaching model of physical education through a comprehensive fuzzy evaluation theory and introduced comprehensive fuzzy evaluation matrix form. The third part designed B/S and C/S joint framework model of computer evaluation of PE curriculum combined with comprehensive fuzzy evaluation mathematical model. Finally, this paper designed the Java programming language taking the evaluation of the students about physical education course for example and concluded the implementation form of the data structure table and designed the physical training computer evaluation system.

Fluorine-doped tin dioxide (FTO) nanocrystals were prepared with sol–gel method using SnCl4·5H2O and NH4F as precursor material. The FTO was characterized with X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Differential Thermal Analysis and Thermal Grativity (DTA-TG) and Infrared Radiation (IR) respectively. The electrical property was measured with Hall Effect Sensor. The result of XRD and SEM shows that FTO nanocrystal size is about 20 nm and the dimension of the grain is about 300 nm. IR spectrum analysis proves fluorine doping. The crystal phase transformation was discussed with DTA-TG curve. When the sintering temperature is 450°C, the sintering time is 60 min, and the molar ratio of F to Sn is 2:10, the sheet resistance of FTO film is 107Ω/□.

A novel multi-walled carbon nanotubes (MWCNTs)-modified glassy carbon electrode (GCE) with excellent stability, repeatability and anti-interference was synthesized and it exhibited an electrocatalytic signal for hydroquinone (HQ) compared to bare GCE, which suggested that the presence of MWCNTs efficiently enhances electron transfer. Various parameters such as pH, modifier volume, and scan rate were optimized using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods. Under optimum conditions, linear responses for HQ in 0.1mol·L-1 phosphate buffer solution of pH 6.0 were obtained in the range of 5×10-6 mol·L-1 to 2×10-4 mol·L-1 with detection limits of 2.7×10-6 mol·L-1 (signal-to-noise ratio of 3). Such MWCNTs-modified GCE was successfully applied for the determination of hydroquinone in simulated water samples and can be developed for the the detection of HQ.

Taking a higher vocational college in Guangdong Province China as a case study, the paper adopts the empirical analysis method to study the problems in the mixed boarding dormitories in higher vocational colleges. The result shows that problems like bad class information sharing, different resting timetable to affect other roommates’ resting and weak learning atmosphere exist on a large scale. It is suggested that the problems could be solved by ways of developing information sharing platform, taking flexible dormitory management, and carrying out curriculum system reform. The data shows 90.8% of the students are content with present situation of the mixed boarding dormitories.

Palladium composite membranes have been prepared using an electroless plating technique with rare earth element of Ce was added into the plating solution. The effects of the rare earth element on the Pd deposition rate, plating temperature and H2 permeation flux were studied. The experimental results show that the additions of mixed rare earth element of Ce into the plating solution can increase Pd deposition rates by 15%. The resistance to sulfidation was examined and the membrane sulfur resistance was confirmed by exposure to a combined gas of H2 and H2S. Keywords: hydrogen utilized; electroless plating; inorganic membrance; Cerium

The mechanism of power ultrasound for preventing gas disaster in coal mines and its application prospect are introduced in this paper. The research results show that, the main mechanisms of power ultrasound on coal are the additional stress shock wave and jet on the crack tips. The permeability of infusion holes around the coal increases, expanding the radius of water infusion moist. The moisture content of the coal body increases and good effect of power ultrasound for preventing gas disaster in coal mines can be obtained. The technology of power ultrasound on gas disaster in coal mines has a good application prospect.

There are various types of corruption risks in the processes of public powers operation. This paper aims at the occupational corruption risks emerging from the exercise of public powers. Combined with the research on the construction project of the system and the introduction of data mining, this paper will probe into the scientific and effective data mining algorithms. By doing so, an electric cage is weaved to curb the abuse of powers by screening and selecting the early warning signs, thus guard against occupational corruption risk problems at the source.

Large-capacity vehicle transmission technology, including dynamic collection of the detection data, has an important significance on the safety detection of the city rail train which is related to the safety of rail transit operation. On the basis of the classification and priority assignment of the detection data, this paper adopts slice sequence dynamic extraction algorithm to establish the information transmission priority queue.

Man, Society and Environment have mutual relationship. Nature and society are interdependent and duty of man to protect them is inherent. It has become common expectation of the whole people to pursue benefit and promote sustainable development between enterprise and society. However, some enterprises stress the nature of enterprise for pursuing profits excessively, not considering the interaction between enterprise and society, denying corporate social responsibility for environmental protection. This article examines the concept of corporate social responsibility of environmental protection, the relations between corporate social responsibility and environmental protection. Finally, the countermeasures for enterprises to undertake responsibility of environmental protection are put forward.

Based on the existing cable failure problems, two features of cable failure problems areput forward. The cablescannot be measured precisely and their characteristics cannot be predicted certainly. In order toanalyze the reliability of cables more reasonably, non-probabilistic reliability theory and its development status are introducedin this article. And the theory of modified one dimensional optimization algorithm is appliedto thereliability analysis of stayed-cable. Its results are comparedwith the results of the probabilistic reliability analysis of stayed-cable. Then the parameters analyses of cableare taken, as a result, the main factors that haveobviouslyinfluence on the reliability of the cable are presented in the article.

In the search for a new method of feature tracking of vector field, Theisel and Seidel proposed the concept of feature flow field [, In their paper, a flat time-varying flow field and multi-vortex structure, vortex will automatically extract and track based on the concept of feature flow field. The method used for tracking the vortex core flow line integral, by extracting the vortex areas of flow field to determine the vortex core range, precision tracking vortex core in the three-dimensional feature flow field and recording the specific path of evolution in the integrand flow line. The new algorithm using the flow line can describe the dynamic behavior of characteristics of vector field. The evolution of the flow field is more intuitive to observe the evolution of different periods, which laid the basis for visualization.

A resolution test-chart for digital camera has been developed based on the knife-edge method. RAW images have been acquired with NikonD7000 DSLR and Canon G12. Set the device color-space to Adobe RGB, and convert the image data to LAB color-space using Adobe RGB profile. The Fourier transfer of the LAB tonal value were computed under MATLAB environment. Then by analyzing the L/C/H (Derived from LAB space ) and the Modulation Transfer Function (MTF), we can get the resolution characteristics of the Nikon D7000 and Canon G12 camera.

Using an improved response surface method analyzed the board of reliability on the elastic half space model. Considered the random of the larger variability parameters, such as foundation, board, load, the paper studied the reliability of this issue application of the response surface method of quadratic polynomials. This paper analyzed the influence of the random parameter variability on the reliability index β and failure probability. Comparison result shows that the convergence of the iteration of this paper is improved than the general response surface method , structural analysis to further reduce the number and improve the computational efficiency, obtained some useful conclusions and had some engineering referencing.

With the increasingly complex new equipment, its maintenance repair training to become a big problem in the process of using the equipment. The traditional training mode by the equipment repair most limit, long development cycle, the characteristics of large investment, based on analysis of virtual repair training system development and function of demand, establish the remote repair system based on VIRTOOLS . The system can create realistic simulation results on the computer, the computer simulation of realistic behavior. The combination of network technology and virtual reality technology organically will provide a technical platform for remote repair service. This paper studies and discusses the architecture of remote repair system based on VIRTOOLS, the key technology and implementation method. And the system structure of remote fault diagnosis system is analyzed.

As the most important index, the navigation accuracy and reliability is used to measure the performance of FOG vehicle integrated navigation system. In the foundation of federated filter and systematic accident diagnose algorithms, a novel integrated navigation filtering algorithm is designed based on FOG SINS(Fiber Optic Gyroscope Strapdown Inertial Navigation System)、GPS(Global Positioning System)、DR(Dead Reckoning). The simulation results show that the federated filter with failure detection can make full use of information from navigation sensor, and can isolate fault sources effectively, its accuracy and reliability are better than the generalized filters’.

For the poor quality of the damage image which is obtained by techniques of practical endoscope detection, the damage image is not easy to identify, this article uses the wavelet transform method for processing damage image, adopts soft threshold method to filter the noise, and then enhances the image, finally employs wavelet transform method in the image edge detection, protrudes the information of the fault and the edge, which is convenient for damage recognition.

Biped robots research is mainly concentrated on the control system development and doing simulation, cubic spline interpolation method is widely applied to pre-gait planning work. This paper analyzed the robots walking process and calculated the joint trajectory curves of a walk cycle by using spline interpolation and the quintic polynomial fitting means, verifies that the result obtained by quintic polynomial algorithm tends to be more ideal, it is conducive to maintain walking stability and find the optimal joint angles. The paper provides a theoretical basis for optimizing robots trajectory planning.

This thesis studies how reinforced steel completes digital length design after being straightened.In general,the analysis of kinematic and dynamic to reinforced steel does not be considered the role of the flexible components in institutional kinematic. The program regards reinforced steel as a flexible body and sees friction wheel as rigid body. The contact between friction wheel and steel is the rigid-flexible coupling[3].With the simulation analysis in ADAMS,I research the problem that reinforced steel produces the slide or not in different speed and contact friction coefficient, in order to determine the design and operating parameters of the cut-to-length body and ensure the accuracy. The result has a good engineering significance in the design of the length structure optimization and operating parameters [4].

This paper focuses on airborne oxygen-making system shortcomings of oxygen sensor characteristic drift in, proposes a method of fault diagnosis. Oxygen sensor with a Wavelet packet analysis of feature extraction, based on wavelet neural network method to determine whether the sensor has failed, and sensor to detect hardware and software design are given.

The system matrix plays an important role in the improvement of medical image reconstruction quality in iterative reconstruction. It consists of a certain sequence of projection coefficients. Projection coefficients indicate the radiological path through a tow-dimensional grid array which is constructed based on the reconstructed image. It is a common geometric problem of evaluating the radiological path through the grid array. This paper identifies the inefficient aspect of the traditionally precise evaluation of the radiological path. A new accurate and simple algorithm is presented, which considers that the projection coefficients can be shown in two-dimensional way. Experimental results based on GATE (Geant4 Application for Tomographic Emission) simulating PET (Positron Emission Tomography) imaging shows that the proposed algorithm is efficient to build up a system matrix, and the image can be reconstructed by the system matrix.

The riveting joint is the main connection to fasten two thin-walled sheet-metal parts in aircraft assembly. As one of important parameters in riveting process, the riveting force is mostly determined by the experience and experiments in actual production, lack of theoretical basis supported. This paper researched the maximum allowed value of riveting force in the elastic deformation stage of riveting process. Based on the theory of compression instability, the mathematics model of relationship among rivets diameter, rivet holes diameter and maximum riveting force was built. Then, by using the software for finite element analysis-ABAQUS, the instance of riveting process simulation was made. Finally, the result of instances simulation was compared with the mathematics model. The comparison shows that the mathematics model based on the theory of compression instability is effective and correct.

Image quality assessment has broad applications in many fields, how to assess the quality of the image is an attractive research topic. In this paper, a ROIMDE method is proposed based on region of interest (ROI) and dual-scale edge structure similarity (SSIM), the quality assessment of the image is a weighted combination of ROI and non-ROI, the dual-scale edge structure similarity is used in ROI, and the classical structure similarity is applied in non-ROI. Experimental results show that, considering the influence of ROI, our model is more consistent with human subjective visual evaluation.

As the important content of modern design method, virtual design plays a key role in machine system optimal design. The VDT (Virtual Design Technology) is discussed in detail. The flow of virtual design is given. Based on the flow of virtual design, the application of virtual design to container loading device is studied.

The riveting joint is the main connection method in aircraft assembly. There are some kind of rivets, such as slug rivet and protruding rivet, that riveting quality will be impacted while rivets axis are not coincident with the plate holes axis. By using the finite element method with ABAQUS software, this paper built the 3D riveting joint structure of finite element, and analyzed the axis deviation effect on the deformation, stress and strain of riveting. Through statistical data, the relationship among axis deviation value, deformation, stress and strain of rivet are built.

Density-functional theory has been used to calculate the energetically global-minimum geometries and electronic states of AgnH2S (n=2, 4, 6) clusters. The lowest-energy structures of Ag2, Ag4, Ag6, Ag2H2S, Ag4H2S and Ag6H2S clusters were obtained, respectively. The calculation results show that the lowest-energy structures of Ag2, Ag4and Ag6clusters are planar geometries. The binding energies of Agn(n=2, 4, 6) clusters are gradually increasing in our calculations. Compare the infrared spectrum peaks of Ag4cluster with that of Ag6cluster, which show that the peaks shift to shortwave. After adsorption, we found that the peaks shift to shortwave by comparison.

All electronic structures and infrared adsorption spectra of AgnH2S (n=3, 5) clusters have been performed by using density functional theory. We obtain the lowest-energy structures of Ag3, Ag5, Ag3H2S and Ag5H2S clusters. The calculation results show that the lowest-energy structures of Ag3 and Ag5 clusters are planar geometries. The lowest-energy structures of Ag3H2S and Ag5H2S can be obtained by adsorbs immediately H2S on Ag3 and Ag5 clusters. The peak of infrared spectrum is 120cm-1 for Ag3 cluster, which is smaller than that of Ag5 cluster (180 cm-1). The peak of infrared spectrum is 350cm-1 for Ag3H2S cluster, which is larger than that of Ag5H2S cluster (290 cm-1). The comparison illustrates that adsorption H2S molecule make the peak of infrared spectrum shifting to shortwave.