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In this paper, APPJ (Atmospheric pressure Pules arc Plasma Jet) is used to generate a DC pulse source depositing GZO thin film under atmospheric pressure. Thus, no vacuum chamber needed leads to the cost downward. With scanning operation, makes single unit area into large size area. Several key process parameters have been studied, including the power supply voltage, DC pulse, the length of the nozzle extended head, and depositing gap to understand their relationship with the film quality and atmospheric plasma state.In this study, with adjusting DC pulse, the pulse frequency is found to have a great impact on the plasma state and the film quality. When the pulse frequency is near 25 kHz, lower sheet resistance can be retained. Besides, adjusting Tofftime, the plasma and thin film quality are influenced more than Tontime. By changing the power supply voltage, the secondary-side voltage decreases with increasing of the instantaneous current; moreover, the plasma will become more intense.

Smell-Seeing Sensor Array consists of two parts. One concerns a sensitive arrays, and the other deals with image collecting and processing technologies. In this paper, a 2×2 sensor array is made by the metalloporphyrin (CuTPP、ZnTPP、NiTPP) and zinc phthalocyanine (ZnPC). Exposed in vapor of 14 different kinds of VOCs (Volatile Organic Compounds) at room temperature, the array appears color change. ARM-Linux system and OpenCV are used to collect and process the color change. This system could detect 14 kinds of VOCs, achieving visualization of gas sensor detection, and laying a foundation of further qualitative identification of VOCs.

A water-soluble fluorescent probe was described for detecting hydrogen peroxide with the naphthalimide derived as fluorophore and boronate moiety as recognition unit. The probe was developed as a turn-on fluorescent chemosensor with fast, high selectivity and sensitivity toward H2O2over other biological reactive oxygen species. What is more, the probe was linear response to H2O2concentration in the range of 2.5×10−8– 3.2×10−5M and lower detection limit down to 12 nM (S / N = 3) was obtained.

In order to improve vehicles comfort, electronically controlled air suspension is taken as study object. We designed the PID controller, which can regulates stiffness and height of air spring. Taking stiffness of air suspension as control variables, and the acceleration of the sprungmass as target values, one-quarter vehicle model of air suspension for bench test is established, then PID control system was tested on the bench.The bench test results show that the PID control algorithm can improve vehicle ride performance.

This paper describes a modeling framework of the center of gravity (COG) analysis system (COGAS) based on the coordination theory and the analytic network process (ANP). Then the framework shows how COGAS is used as basis of construction, calculation and analysis of the COG networks. The importance of this work is that it uses the coordination theory to identify the dependencies on target, and it augments the ANP to support rapid decision-making and overcome the subjectivity of human.

Plasticizer wastewater of high concentration was experimentally studied by the process of pretreatment of acidification demulsion and Fe-C micro-electrolysis and combined process of UASB and A/O aiming at the CODCrremoval in this work. The result showed that the CODCrremoval rate of pretreatment process arrived at 56.2% after Fe-C micro-electrolysis reaction of 160 min on the optimal condition of pH 3.5 of acidification demulsion and 1:1.2 of the Fe/C ratio, and meanwhile improved the biodegradability of wastewater. On the other hand, UASB-A/O process could afford 80~85% of the CODCrremoval rate under the optimized condition of temperature 30~35 °C, HRT 48h, pH 6.5 for UASB and HRT of aerobic zone 10~12 h, DO of about 3mg/L for A/O basin. The whole system could run at the total CODCrremoval rate of 94.53~96.36%, and the system effluent CODCrwas 500 mg/L or less.

Titanium dioxide (TiO2) has widely been applied in various fields of industry and technology. To improve the corrosion resistance of TiO2, many manufacturing processes have been researched. MAO is a new method of the TiO2 manufacturing process, of which titanium dioxide is coated on titanium substrate. According to electrochemistry researches, there is a more superior level for Pulse-MAO than traditional MAO. Parameters of on-time were significant in the Pulse-MAO process. The results show that on-time affects reactant shape, morphologies, thickness of films, and corrosion resistance. When on-time increased, the size of reactants was bigger and the shape of reactants was changed from sphere to lump. Meanwhile, the corrosion resistance and thickness of the film increased.

Expensiveness and lack of N-pixels sensor affect the application of terahertz imaging. New compressed sensing theory recently achieved a major breakthrough in the field of signal codec, making it possible to recover the original image by using the measured values, which have much smaller number than the pixels in the image. In this paper, by comparing the measurement matrices based on different reconstruction algorithms, such as Orthogonal Matching Pursuit, Compressive Sampling Matching Pursuit and Minimum L_1 Norm algorithms, we proposed a terahertz imaging method based on single detector of randomly moving measurement matrices, designed the mobile random templates and an automatically template changing mechanism, constructed a single detector imaging system, and completed the single terahertz detector imaging experiments.

Indole and its derivatives extensively exist in nature, which showed a wide range of biological activities. Recently, there is a growing tendency to develop some new methods for the synthesis of novel indole derivatives and to study their biological properties. In this paper, we would like to report the design, synthesis and biological evaluation of a novel series of tricyclic indoles by employing Pictet-Spengler reaction as key step. All the target compounds were synthesized in four steps in 68-78% overall yield, which were characterized by 1H-NMR spectrum. All this new compounds were tested in an MTT assay on HepG2 and K562 and HT-29. Two of them showed tumor cell growth inhibitory good activity.

Concrete embedded fiber Bragg grating strain sensors are used to monitor real-time strain of each section in the tunnel surrounding rock supporting structure, and the nonlinear regression analysis method is adopted to analysis the real-time measurement data. By using nonlinear regression analysis method, the strain development status of surrounding rock supporting structure can be grasped timely and the variation trend of the strain value of monitoring point can be predicted, which can provides foundations for judging the stability of tunnel supporting structure.

The sensing finger pressure does not meet the requirements can cause isolation switch overheating, even lead to accident in the operation of high voltage isolate switch. According to the structure of isolating switch, FBG pressure sensor and FBG displacement sensor are installed on isolate switch, which constitute the sensing finger pressure detection system. The sensing finger pressure detection experiments indicate that, when the moving contact’s closing position of isolate switch changes from 0.267mm to 29.040mm, the sensing finger pressure ranges from 30.378N to 32.970N.However, when spring pressure changes from 42.776N to163.827N, the sensing finger pressure ranges from 29.033N to 111.193N.The sensing finger pressure measuring system can realize real-time and online monitoring of the sensing finger pressure.

In the stretching process, scratch is on the main defects affecting parts’ quality and is the quality problem, which is difficult to solve. This paper analyzes the main cause of quality problem the tensile parts caused, and puts forward some methods to solve.

A phthalocyanine derivative: 2,9,16,23-tetra-tert-butyl-29H,31H-copper(II) phthalocyanine (CuttbPc) was used as an optical gas sensor based on Langmuir-Blodgett (LB) films. Surface pressure-area per molecule (π–A) isotherms and Brewster Angle Microscopy (BAM) will show the process of the monolayer formation at the air-water interface. The responses of the thin films to various volatile organic compounds (VOCs) were recorded by UV-Vis absorption spectra and the morphological characterization was performed by Atomic Force Microscopy (AFM). The experimental results indicate that highly-ordered and uniform films can be prepared at about 33mN/m with the transfer ratio of 0.7. The results also demonstrated that CuttbPc LB films are promising to be applied into optical gas sensors for VOCs detection and recognition.

Bellows is a thin-walled metal cylindrical with folds, as a pipeline connection and compensation device, it has the feature such as reliable and compact. Now Bellows is widely used in the produce of aerospace engines and the relative industries. In order to solve the load life test problem of bellows, the squeezing and twisting process after the long time loading is simulated by swinging and pressing it rapidly in a short time. Adopting NI Real-Time Hypervisor，a real-time monitor and test system is built by Windows operation system. According to the real twist data of bellows,the dynamic equation of swing platform for two cylinder is constructed, by the real-time and a high precsion control of the motion of two cylinders, the bellows which is full of liquid has been squeezed and twisted with a high frequency, and loading test of the mechanical properties, strength and lifetime for bellows is achieved in an automatic way.

Two-phase heat transfer devices such as heat pipes and vapor chambers are composed of an evaporator, an adiabatic section and a condenser. For the dry-out prevention and capillary purpose, adiabatic sections and evaporators are covered by wick structures. Common wick structures are grooves, mesh, sintered powder and their combination. Combining with the wick structures, the major phase change effects on evaporators are thin-film evaporation. For the research between parameters of wick structure and evaporator performance, we developed a facility to measure the heat transfer on evaporators. To ensure the least heat losing, the path of heat flux and test condition were designed with several thermal guards. A pressure control system was established with balance mechanisms to maintain a stable condition of low pressure. Since temperature differences are very fast while the major phase change effect is thin-film evaporation, a high speed data acquisition system was used. Based on this test platform, the performance of evaporators can be determined at specific conditions.

In allusion to the problems such as the poor flatness of the parts , not-easy-guaranteed aperture precision, low strength and short service life of mould that occur in stamping production of the screen hole parts, this article detailed introduced the diamond punching method and at the same time it summarized the maintenance of the mould that this method uses

Humic acid and protein are two major organic matter types encountered in natural and polluted environment, respectively. This study employed Triple Pulse Experiments (TPEs) to investigate and compare the influence of Suwannee River Humic Acid (SRHA) (model humic acid) and Bovine Serum Albumin (BSA) (model protein) on colloid deposition in a column packed with saturated iron oxide-coated quartz sand. Study results suggest that adsorbed SRHA may inhibit colloid deposition by occupying colloid sites on the porous medium. Conversely, BSA may promote colloid deposition by a ‘filter ripening’ mechanism. This study provides insight to understand the complex behavior of colloids in organic matter-presented aquifers and sand filters.

Compared with traditional etch processing, inkjet technology has the features of simpler workmanship, less resources-utilizing, lower cost and environmentally friendly adaptation, which is sure to be another innovation of printed circuit board(PCB) technology. In this paper, size and shape controlled silver nanoparticles have been synthesized，which was used as conductive medium in ink-jet inks. Then it was printed into conductive lines on epoxy resin by a drop-on-demand inkjet printer. PVP was used as a polymeric stabilizer providing both electrostatic and steric stabilization. Ag2C2O4 was used to prepared spherical nano-silver. In the preparation of flake-like silver powders, the fully inorganic phase system contains AgNO3 as a silver precursor, DMF as a as a media dissolving silver salt, and PVP as a reducing reagent. The morphologies and structures of the nanoparticles were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was shown that the sample is silver with cubic asymmetry from the pattern of XRD. TEM images indicated that the size of spherical nano-particles was no more than 20 nm. But the small triangular nanoplates, with rather narrow size distribution, were in the range from 20nm up to 60 nm in edge length. The electrical conductivity was also measured by the four-probe tested method after calcined on the substrates. It was shown that the conductivity was 25S/cm when adding the spherical powders and the nano-silver ink has been successfully designed for inkjet printing.

There are lots of methods of evaluating the environmental quality of groundwater. Based on a comprehensive analysis of those common methods, this paper puts forward a method named fuzzy comprehensive evaluation method on water environmental quality based on entropy weight with consideration of toxicology of evaluation factors. Developed from the entropy-based fuzzy comprehensive evaluation method, this method takes into account the influences caused by the toxicology weight and over standard weight of evaluation factors on the calculation of entropy weight. Through some water samples, the evaluation result of this method is more reasonable, objective and comprehensive than the one which is concluded from the entropy-based fuzzy comprehensive evaluation method.

In the past half century, EDM (electrical discharge machining) is one of the most popular methods for manufacturing casting and plastic injection molds. Unlike other traditional mechanical cutting methods, EDM removes materials away by sparks, which leads to high temperature and pressure. As a result, it has no restriction to hardness because of its non-contact property. However, there will be recast layers on the surface of work-pieces and thus the surface need improved. In order to decrease the surface roughness, we added different powders into dielectric to become ERF (electrorheological fluid). By rotating spindle, the chain structures of ERF can improve surface of SKD11. The result shows that, when the gap is 100μm and electrode φ2, starch has 61% improvement rate and Al2O3 has 14.97%.

Dry Electrical discharge machining (Dry EDM), using gas as dielectric, has been developed to solve problems against environment. It has both advantages of high material removal ratio (MRR) and low relative electrode wear ratio (REWR). We investigated the effect of duty factor, peak current, and reference ratio of gap voltage on MRR and REWR of Dry EDM, respectively. Moreover, trying to prove the attachment on electrode surface could decline REWR. It is considered that melting material of work-piece was sputtered and stuck onto electrode surface, and to become a protection layer as result in low REWR. However, the attachment will be removed under the condition of high peak current and high discharge frequency. But the amount of attachment just has little change when discharge number and arc discharge ratio are both decrease.

Suspending powder in dielectric fluid of EDM (electrical discharge machining) has been developed to improve the quality of machined surface recently. The used powders are usually Al, Cu, Cr and so on metal powder because conductive particle can increase the spark gap and improve surface roughness of machined surface. Semi-conductive powder, Si is also utilized for the sake of increasing machining speed. This paper presents a new tryout to suspend polymer particles in the dielectric fluid of EDM. Experimental results show that the EDM process with suspending polymer particles still can be carried out but its surface roughness is not so good in conventional EDM oil. However the conventional EDM oil was taken the replace of silicone oil, suspending polyaniline (PANI-emer) of high molecular weight (Mw~65000) has finer improvement even better than using Si powder. Its surface roughness achieves less than Ra 0.2μm at low concentration and will be decreased gradually with increasing the concentration of PANI-emer (Mw~65000). The surface roughness is Ra 0.14μm when the powders concentration is 10g/l. Even for different type of polyaniline shows different machining characteristics. The surfaces roughness becomes worse when the concentration of low molecular weight PANI-emer (Mw~20000) is higher. An electric-conductive PANI-salt powder has a rapid decrease of surface roughness with increasing its concentration than other materials.

A new cutting force model of micro-milling was developed based on calculating the instantaneously projected area of cutting in this study. According to the rotation trajectory of cutting edge, the instantaneous cutting area projected to xy-plane was first divided into several portions and determined with rectangular integral. After the cutting coefficients were experimentally investigated, the cutting force of micro-milling with different cutting conditions can be determined. Because the developed cutting force was function of cutting parameters, such as spindle speed, feed rate, depth of cut, with taking the cutter deflection into account it was further used to the determine of optimal cutting parameters for obtaining better cutting efficiency and machining accuracy. To verify the proposed cutting force model and the way to determine the optimal cutting parameters, micro-milling experiments were conducted. The results have shown the feasibility of the proposed model and method.

By combining the advantages of a catalytic palladium (Pd thin film) with a high-performance GaAs-based transistor, an interesting hydrogen sensor is fabricated and demonstrated. For the studied device, a 50 Å undoped GaAs cap layer is grown to prevent the Al0.24Ga0.76As Schottky layer from oxidizing and to suppress the Fermi level pinning effect. The sensing mechanism can be described as the dissociation of hydrogen molecules and the polarization of hydrogen atoms. The drain-source variation ΔIDS is caused by the polarization of a dipolar layer resulting in the modulation of the gate potential and carrier density level. Experimentally, a high hydrogen detection sensitivity SJ value of 275.8 mA/mm-ppm H2/air can be obtained under the 14ppm H2/air gas. Even under a very low hydrogen concentration (≤4.3 ppm H2/air) at 303K, the considerable current variation can be observed. Moreover, the fast hydrogen response is found. Therefore, the studied device reveals the promise for high-performance hydrogen sensor applications.