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Fluorescent tracers are frequently used in spray tests, but their stability under illumination and rate of elution and recovery from the deposition carrier are crucial to the accuracy of the test results. Spectral analysis has shown that the absorbing wavelengths for RhB and BSF are 573.8 nm and 494.6 nm, respectively, at most under uninterrupted sunlight and their recovery rates are 93.5%–98.2% and 95.5%–99.4%, respectively. In favourable light stability, a great part of both colouring agents can be eluted and recovered from glass slides and mylar card but not so much from filter paper. Because of the tracers being influenced by light, when using a mylar card as a receiver, different coloured plastic boards were used as pads, and it was found that a red pad can increase the recovery of elution by three percent in 2 hours. Our goal was to determine which chemicals would be most suited for use as tracers for the simulation of long-distance transport of pesticides in aerial spraying by evaluating the effects of spraying pattern on spraying deposition and drift potential of pesticide sprays. Tests undertaken on a farm showed that the two colouring agents studied can be effectively used as tracers to investigate droplet deposition of pesticides sprayed by a UAV on paddy rice farms in a low volume. The above test results show that RhB can be feasibly used as a tracer to examine droplet deposition of pesticides aerially sprayed in a low volume.

Casting Mg-Li alloy samples were subjected to solid solution treatment with different temperatures and aging with different times, and the corrosion resistance of different samples was investigated by potentiodynamic polarization measurements in 3.5% NaCl solution. The results show that the corrosion resistance of the Mg-Li alloy is improved with increasing solution temperatures and aging times.

Mesoporous cobalt doped aluminium oxide (Co/MAl2O3/RL) was synthesized using rubber latex as biotemplate by hydrothermal method. The synthesized mesoporous aluminium oxide samples were characterized by a combination of various physicochemical techniques, such as X-ray diffraction (XRD), N2adsorption/desorption and Fourier transform infrared (FT-IR). Espciallly, Co/MAl2O3/RL exhibited a high efficiency of acetaldehyde adsorption from mixed gaseous mixture.

Carbon nanotubes (CNTs) were prepared on Si substrate by radio frequency plasma-enhanced chemical vapor deposition with Ni/MgO as catalyst. The morphology and microstructure of CNTs were characterized by X-ray diffraction, scanning electron microscopy, Raman spectroscopy, and transmission electron microscopy. The results show that with increasing MgO concentration in the catalyst the diameter of CNTs becomes smaller and more uniform and their purity and crystallinity are improved. Open or close carbon nano-onion structure is formed at the top of the CNTs, and the catalyst particles are found inside the tubes. With increasing MgO concentration, nanoparticles tend to nanowires longer than 30 nm for MgO concentration of 75% in the catalyst compund. These nanowires are made by Ni. Besides, when MgO concentration is 50%, the graphite layer of the bending tube wall extends inside of the tube, dividing the cavity into several irregularly shaped spaces, which forms a new carbon nanostructure.

In this research, Ni/MgO is used as catalyst and CNTs were synthesized by radio-frequency plasma enhanced chemical vapor deposition (RF-PECVD), and then liquid oxidation method was used to purify CNTs. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscope and infrared spectroscopy were used to study the influences of purification time on morphology and microstructure of CNTs. The results show that CNTs synthesized by RF-PECVD contain a great amount of impurities. With the increasing of purification time, the impurities decreased. Meanwhile, carboxyl oxygen-containing groups introduced on the surface of CNTs are also gradually increasing along with purification time. And the crystallization properties of CNTs increased first but decreased then with the introduction of a large amount of oxygen-containing groups. The surface modification of CNTs has very important significance for the applications of CNTs in the field of electrochemical biosensor.

As a new functional material, foam aluminum is characteristic of sound absorption and vibration attenuation. A multiple structure is put forward which composed of foam aluminum and base blankets. The sound insulation performance is investigated. The method of sound transmission loss for normal wave incidence is developed. The influences of different thick foam aluminum on the multiple structures are analyzed by numerical method, also verified by experiments. The results show that experimental results are in good agreement with the theoretical predictions and the thickness of foam aluminum has a great impact on the multiple structure’s sound transmission loss.

In order to develop the green manufacturing and microfabrication, an innovative micro-electrochemical machining (ECM) method¬¬-the electrochemical machining in pure water was studied. On the base of experimentation principle, ECM set up was developed for engineering application. Water dissociation mechanism is found under the function of cation exchange membrane, and many factors to enhance current density were analyzed. As a result of technological test, a micro hole is machined in the thin stainless. It is confirmed that electrochemical machining technology is feasibility to make use of pure water as electrolyte.

The performance and biodegradability of plant fibre and starch dishware (PFSD), pulp model dishware (PMD) and starch plastic dishware (SPD) were studied. The experimental results showed that these three kinds of dishware satisfy the requirements of use. The fungi growth degree and the weight loss percentage of these materials were analyzed. The experimental results showed that the growth grade of PFSD and PMD were both Ⅴgrade and the weight loss rate respectively were 41.59% and 82.73%, the biodegradability of SPD was not obviously observed in the whole process of the experiment. The degradation speed was analyzed, which showed that the degradation speed of PFSD and PMD was faster in the former two weeks than that in the latter two weeks. The biodegradability of each kind of dishware were compared under three different environments, the results showed that inoculation environment (T=30°C, RH>90%, 28 days) is the best environment for dishware to biodegrade by fungi.

The composite materials TiN/3Y-TZP, 3Y-TZP doped by TiN with different contents and particle sizes, were fabricated through the same hot-pressing techniques. Compared with 3Y-TZP, the low temperature degradation resistance of TiN/3Y-TZP aged at the temperature from 170°C to 350°C in air for 50 h was investigated in virtue of XRD and SEM in the experiment. For TiN/3Y-TZP and 3Y-TZP, the maximum aging rate all occurs at 220°C. The addition of TiN can availably improve the low temperature degradation resistance of 3Y-TZP at different aging temperatures, but cannot change the relationship between the aging rate and the aging temperature. For TiN/3Y-TZP, the matrix particle size is the key factor responsible for its low temperature degradation resistance.

A semiconductor gas sensor of tin oxide doped with hydroxyl (OH) functionalized multi-wall carbon nanotubes (MWCNTs) was fabricated for detecting indoor formaldehyde concentration. The response of the MWCNTs-doped SnO2 sensor was much higher than that of an undoped SnO2 sensor. In order to detect low concentration formaldehyde, a novel enrichment method utilizing active carbon was applied. The response of the sensor was obviously increased by the application of the enrichment method. The lowest concentration of formaldehyde gas detected by a 5 wt% MWCNTs-doped SnO2 sensor was 0.03 ppm.

A liquid-core optical fiber is used to measure the temperature from the intensity ratio of Ramanscattering lines. CCl4 doped with benzene, which ensures conditions for the total internal reflection, serves as the fiber core. Measurements were performed at three Raman-scattering lines in CCl4: 218, 314, and 459 cm−1. The results obtained at 459 cm−1 best correspond to the actual temperature. The advantages of using a liquidcore optical fiber and factors affecting the measurement results are discussed.

A novel method to measure the temperature on the surface of micro-hotplate was presented. The tiny fiber probe and the optical power meter were employed to measure the sample radialization power. By means of comparing the relationship between the radialization power and the temperature, sample surface temperature can be discerned accurately. Such an approach has provided more accuracy than traditional temperature measurements. The experimental result based on this method is quite similar to that of simulation by the finite element analysis (FEA) software of Ansys in theory. This measurement is very useful for measuring temperature for these micro samples prone to be untouchable.

Humidity sensing composite material is made of nanocrystalline BaTiO3 and polymer polystrene sulfonic sodium (PSS). The composite material is spin-coated onto a ceramics substrate to fabricate humidity sensor. The electrical properties of the sensor are measured. The resistance verse the relative humidity (RH) of the sensor enjoys good sensitivity and linearity in the range of 33–98%RH. The capacitance and the impedance of the sensor change with different frequency and RH. The frequency ranges from 20 Hz to 100 kHz in the plots. Complex impedance plots are semicircles at low RH and a semicircle connected with a line at high RH, respectively. The different kinds of the impedance plots represent the different sensing mechanism for the composite material BaTiO3/PSS humidity sensor.

In order to explore a new material of noise pollution control, transmission loss of metallic foams was analyzed for local resonance. And a model on sound insulation loss of the closed-cell metallic foams plate was presented on base of the former and correlative theory. The results show that sound insulation property of the closed-cell metallic foams plate is a biggish change with the different parameters. And it is found that sound insulation loss of the closed-cell metallic foams plate has an extreme value to the some frequency. It is reckoned that there is a phenomenon of the brush-fire sympathetic vibration in closed-cell metallic foams plate. The resonance may sometimes greatly improve the effect of sound insulation. The result will be very important to future engineering application of the closed-cell metallic foams plate.

This paper deals with the properties of films used as entrance window of a gas-flow type ultrasoft X-ray counter. The effects of the base material and conductive coatings of the films on performance characteristics of the counter are investigated. Experimental results show that, among the material under study, Formvar exhibits more satisfactory gas-sealing property and has higher transmissivity for X-rays. In addition, it is found that the conductive coating on the film has a significant effect on the stability of the measured intensity. An interpretation on these effects by taking into acounts of the feature of electron multiplication process in the counter caused by ultra-soft X-rays is proposed.