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The WRKY transcription factor superfamily is known to participate in plant growth and stress response. However, the role of this family in wheat (Triticum aestivum L.) is largely unknown. Here, a salt-induced gene TaWRKY13 was identified in an RNA-Seq data set from salt-treated wheat. The results of RT-qPCR analysis showed that TaWRKY13 was significantly induced in NaCl-treated wheat and reached an expression level of about 22-fold of the untreated wheat. Then, a further functional identification was performed in both Arabidopsis thaliana and Oryza sativa L. Subcellular localization analysis indicated that TaWRKY13 is a nuclear-localized protein. Moreover, various stress-related regulatory elements were predicted in the promoter. Expression pattern analysis revealed that TaWRKY13 can also be induced by polyethylene glycol (PEG), exogenous abscisic acid (ABA), and cold stress. After NaCl treatment, overexpressed Arabidopsis lines of TaWRKY13 have a longer root and a larger root surface area than the control (Columbia-0). Furthermore, TaWRKY13 overexpression rice lines exhibited salt tolerance compared with the control, as evidenced by increased proline (Pro) and decreased malondialdehyde (MDA) contents under salt treatment. The roots of overexpression lines were also more developed. These results demonstrate that TaWRKY13 plays a positive role in salt stress.

The WRKY transcription factor superfamily is known to participate in plant growth and stress response. However, the role of this family in wheat (Triticum aestivum L.) is largely unknown. Here, a salt-induced gene TaWRKY13 was identified in an RNA-Seq data set from salt-treated wheat. The results of RT-qPCR analysis showed that TaWRKY13 was significantly induced in NaCl-treated wheat and reached an expression level of about 22-fold of the untreated wheat. Then, a further functional identification was performed in both Arabidopsis thaliana and Oryza sativa L. Subcellular localization analysis indicated that TaWRKY13 is a nuclear-localized protein. Moreover, various stress-related regulatory elements were predicted in the promoter. Expression pattern analysis revealed that TaWRKY13 can also be induced by polyethylene glycol (PEG), exogenous abscisic acid (ABA), and cold stress. After NaCl treatment, overexpressed Arabidopsis lines of TaWRKY13 have a longer root and a larger root surface area than the control (Columbia-0). Furthermore, TaWRKY13 overexpression rice lines exhibited salt tolerance compared with the control, as evidenced by increased proline (Pro) and decreased malondialdehyde (MDA) contents under salt treatment. The roots of overexpression lines were also more developed. These results demonstrate that TaWRKY13 plays a positive role in salt stress.

The essential oil of Mentha canadensis aerial parts was obtained by hydrodistillation and analyzed by gas chromatography (GC) and gas chromaotography-mas spectrometry (GC-MS). A total of 36 components of the essential oil were identified. The major constituents in the essential oil of M. canadensis were menthol (28.8 %), α-pinene (16.4 %), menthone (12.7 %), α-terpineol (6.3 %) and limonene (5.5 %). Four active constituents (limonene, menthol, α-pinene and α-terpinol) were isolated from the essential oil of M. canadensis based on bioactivity-directed fractionation. The essential oil of M. canadensis aerial parts exhibited nematicidal activity against cereal cyst nematodes (Heterodera avenae) and root-knot nematodes (Meloidogyne incognita) with LC values of 385.7 μg/ml and 139.0 μg/ml, respectively. The isolated constituents, menthol and α-terpinol possessed nematicidal activity against H. avenae and M. incognita with LC50 values of 242.5 μg/ml, 190.3 μg/ml and 147.4 μg/ml, 115.2 μg/ml, respectivel...

This paper presents two electromagnetic vibration energy harvesters based on micro-electro-mechanical (MEMS) technology. Two prototypes with different vibration structures were designed and fabricated. The energy harvester includes a permanent magnet attached on vibration structure (resonator) made by Si and a fixed wire-wound coil, with the total volume of 0.9 cm3. Two energy harvesters with different resonator are tested and compared. Experiments show that: in the same acceleration and a load resistance, the resonant frequency of prototype B is approximately 95% of prototype A; The peak-peak voltage and the maximum power of prototype B is 1.6 times and 2.7 times of prototype A respectively. The test results was analyzed simply and it indicated that the electromagnetic energy harvesting with the spring B has better performance; also proved that the potential ability of the non-linear spring could extend the frequency bandwidth and improve output voltage.

In the design of the micro electromagnetic vibration harvester, an important goal is maximization of the magnetic flux linkage gradient, which directly determines the induced voltage and output power of the electromagnetic vibration harvester. This paper established a numerical model based on structure of the electromagnetic vibration energy harvester. An analytic expression for the magnetic field of rectangular permanent magnets is used to build up an electromagnetic coupling model. The magnetic field distribution of the rectangular permanent magnet was analyzed. The effects of the gap between the magnet and the coil on the load voltage of the electromagnetic vibration energy harvester were investigated. According to the formula, the magnetic flux linkage and flux gradient were calculated to optimize the geometrical parameter of the magnet and coil. The method and boundary conditions of optimizing the gap between the magnet and coil were presented. The maximum output voltage can be obtained by optimizing the gap between the magnet and the coil. A simple prototype was fabricated and measured to validate the theoretical deducing and the feasibility of method.

The finite element method to obtain the stiffness of MEMS (Micro-Electro-Mechanical Systems) accelerometer is difficult to give an exact expression, so a new method to analyze the stiffness of MEMS accelerometer was purposed. Both Mechanics and electricity analysis were used to calculate the stiffness of vacuum microelectronic accelerometer developed in our laboratory, and the control and detection circuits were design according to the result. Finally, the sensitivity, linearity and other performance were measured through the static gravitational field experiments; the least squares curve fitting correlation coefficient 0.9999 and linear 0.9%. The result shows that this method to analyze the stiffness of the stiffness of vacuum microelectronics accelerometer is correct and feasible, and this method can also be applied to other MEMS accelerometer with symmetrical structure and electrostatic force balance mode.

A compact, low cost, high speed, non-destructive testing NIR (near infrared) spectrometer optical system based on MOEMS grating device is developed. The MOEMS grating works as the prismatic element and wavelength scanning element in our optical system. The MOEMS grating enables the design of compact grating spectrometers capable of acquiring full spectra using a single detector element. This MOEMS grating is driven by electromagnetic force and integrated with angle sensor which used to monitored deflection angle while the grating working. Comparing with the traditional spectral system, there is a new structure with a single detector and worked at high frequency. With the characteristics of MOEMS grating, the structure of the spectrometer system is proposed. After calculating the parameters of the optical path, ZEMAX optical software is used to simulate the system. According the ZEMAX output file of the 3D model, the prototype is designed by SolidWorks rapidly, fabricated. Designed for a wavelength range between 800 nm and 1500 nm, the spectrometer optical system features a spectral resolution of 16 nm with the volume of 97 mm × 81.7 mm × 81 mm. For the purpose of reduce modulated effect of sinusoidal rotation, spectral intensity of the different wavelength should be compensated by software method in the further. The system satisfies the demand of NIR micro-spectrometer with a single detector.

The capacity of charge storage for supercapacitor depends on the size of the electrode surface area and the active material on the electrodes. In this article, we fabricate the three-dimensional microelectrodes with SU-8 photoresist based on the microelectromechanical system technology to increase the electrode surface area and to carry more active materials on the electrodes. The three-dimensional microelectrode was directly prepared by the method of anodic electrodeposition. Its surface and composition were characterized by scanning electron microscopy and energy dispersive spectroscopy. Moreover, cyclic voltammetry and galvanostatic charge–discharge current are also used to test the electrochemical characteristics of the manganese oxide electrodes. When the discharge density is 0.5 mA cm−2, the areal capacitance for the fabricated three-dimensional microelectrodes with microstructure and the two-dimensional planar microelectrodes without microstructure is 3.68 mF cm−2 and 1.0 mF cm−2, respectively. The experimental results show that the three-dimensional microelectrode structure prepared with microelectromechanical system technology can effectively increase the electrode surface area and carry more electroactive materials, thereby enhancing the charge storage capacity of the electrodes.

A new fabrication method to produce low residual stress PECVD SiNx layers at high frequency (13.56 MHz) was developed. High frequency up to 60W is employed in this new method to fabricate low stress SiNx. By adjusting the composition of reactant gases, process vacuum and the chamber temperature, the residual stress can be lower to-0.28 MPa, and high deposition rate up to 240 nm/min can be achieved. In addition, this paper investigated the influence of other important parameters on the results, such as pressure, power and gases flow rates. Moreover, by using the optimal process, the refractive index is ranged from 1.98 to 2.20, and the uniformity of run to run wafers is about ±3% for 4 inch wafers. Finally, a typical FBAR (film bulk acoustic wave resonator) structure using these low stress PECVD SiNx layers as solid layer and mask indicated that these layers are compatible in IC technology and suitable for using in fabricating MEMS(microelectromechanical systems) devices.

Field emission accelerometer work in vacuum environment, the negative exponential relationship between the current and the distance of the cathode and anode electrode make the accelerometer has high sensitivity and serious non-linearity. A system simulation method by using SIMULINK tools was put forward, and the system simulation model was proposed. The system simulation was carried out under low vacuum and high vacuum environment. On the guidance of the simulation result, the circuit was designed and the performance of accelerometer was tested. The result indicated that the accelerometer have good linearity and sensitivity.

A micro piezoelectric cantilever beam array is designed for vibration energy harvesting. A single degree of freedom analytical model is developed to predict the properties of the device and is verified by finite element method. The piezoelectric material Aluminum Nitride was chosen for the compatibility with the CMOS process. The devices consisting of 5 piezoelectric cantilever beams and one proof mass were fabricated using micromachining technology. The resonance frequency, voltage and power were tested at excitation acceleration of 5.0 g. The maximum output power of the device is 9.13 μW at the resonance frequency of 1315 Hz when piezoelectric beams are connected in parallel.

This paper describes the fabrication and measurement results of piezoelectric energy harvester arrays based on aluminum nitride (AlN) as a piezoelectric material. The AlN piezoelectric thin film with crystal orientation (002) and crystal orientation (101) is deposited respectively by pulsed_DC sputtering on the different bottom electrode materials. Based on the AlN thin film, the piezoelectric vibration energy harvester arrays with 5 cantilever beams were developed. Then the load characteristics, frequency characteristics, harvester connected in series and parallel properties of harvester were investigated. In addition, we compare the properties of piezoelectric vibration energy harvester arrays with crystal orientation (101) and (002), where a record max power output of 0.23 μW and 0.38μW are obtained respectively when the value of acceleration was 1 g, while for the latter, the maximum power is 9.13 μW at the acceleration of 5.0g with the optimized resistance of 15 kΩ.

The capacity of supercapacitor charge storage depends on the size of the electrode surface area and the active material on the electrodes. To enhance the charge storage capacity with a reduced volume, silicon is used as the electrode material, and three-dimensional electrode structure is prepared to increase the electrode surface area on the footprint area by inductively coupled plasma reactive etching (ICP) techniques. The anodic constant current deposition method is employed to deposit manganese oxide on the electrode surface as the electroactive material. For comparison, samples without slot are prepared with a two-dimensional electrode. Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) are used to characterize the surface morphology of the electrode structure and the deposited electroactive material. Electrochemical properties of the electrode are characterized by the cyclic voltammetry (CV) and the constant current charge-discharge method. Experimental results show that our approach can effectively increase the electrode surface area with more electroactive substances, and hence can increase storage capacity of the micro-supercapacitor.

In order to increase the electrode surface area and enhance the charge storage capacity, we study the micro electro mechanical system technology to fabricate three-dimensional high aspect ratio micro-electrode structure based on glass. The anodic constant potential method is employed to deposit manganese oxide as electroactive substances on the micro-electrode surface. Cyclic voltammetry and constant current charge-discharge method are both used to prepare electrode electrochemical performance testing, with a two-dimensional electrode without structure for comparison. Experimental results show that three-dimensional electrode structure can effectively enhance the charge storage capacity. At 1.0 mA/cm2 charge-discharge density, the three-dimensional electrode shows a capacitance of 17.88 mF/cm2, seven times higher than the two-dimensional electrode.

In order to realize more compact and in particular cost-effective spectrometers MOEMS technology offers attractive possibilities. Based Littrow spectrometer structure for the near-IR, a micro mirror grating spectrometer has been designed and developed. The ZEMAX was used for designed this structure. The resolution of this design is 10nm, the spectral range from 900nm to 1400nm. A scanning micro mirror is the key element of this IR spectrometer set-up. This micro mirror is driven by electromagnetic force. Before fix the micro mirror, it was calibrated. Meanwhile, for reducing the cost of this system, the silicon silt was designed and fabricated. For resolution testing of this spectral system, we used one light correction filters finished this experiment. The test result has shown the resolution of this spectrometer is16.8nm. Finally, the relation between the spectral line scanning characteristic and wavelength spectral resolution was discussed.

A novel miniaturized piezoelectric wind flutter generator is proposed which consisted of a flexible beam and a PZT cantilever. The working principle is based on flexible beam flutter, which can amplify the PZT cantilever vibration. A prototype was tested in a wind tunnel. It is found that there are three behavior states with wind speed increasing, and flutter behavior takes place when wind speed varies between the critical wind speed Uc1and Uc2, an empirical formula was obtained about the critical speed Uc1. The open circuit voltage and power were measured. The device can generate 794μW output power with 30kΩ resistor in a wind of speed 20m/s, power density is 139μW/cm3.

This paper presents a capacitive biaxial microaccelerometer with a single proof mass. The theoretical analysis results are confirmed by finite element analysis. The experimental results indicate the biaxial accelerometer with uniform axial sensitivities, good linearity and high cross-axis sensitivity immunity to the z-axis input.

This work focuses on the development of a biaxial fully differential capacitive microaccelerometer with a single proof-mass. Its design, optimization and fabrication are discussed in detail. Structure and geometric parameters are optimized by multidisciplinary design optimization, enabling ±1g operating range, 1182Hz resonant frequency, 97 fF/g sensitivity, 4.1mg resolution and 0.68 damping ratio. Silicon-on-glass (SOG) bulk micromachining and inductively coupled plasma (ICP) etching technologies are adopted to fabricate this accelerometer.

A programmable micro mirror has been used in a near infrared spectrometer in order to achieve the purpose of signal multiplexing, to solve the problem of low luminous flux when using single slit and to increase the signal-to-noise (SNR) ratio. Use Hadamard Transform (HT) and programmable micro mirror as its encoding mask to detect the whole spectrum with a single detector, research and analyze the enhancement of SNR of the weak signal. First of all, the mask symbol number is fixed as 63-order based on the Hadamard Transform principle, calculate the optimal S-Matrix, and then the encoding mask has been realized by micro mirror. At last, carry out some experimental verifications as well as data analyzing, discuss the alternating spectrum signal which produce an effect on transformational algorithm, bring out the coadded upswing plan. The result shows that: the conflict of resolution and SNR can be well settled with Hadamard multiplex. The SNR can be increased by the factor of 3.5, which is identical with the theoretic result.

The realization of Hadamard Transform (HT) encoding mask is the key technology to Hadamard Transform Spectroscopy. In order to realize HT mask using DMD, the theory of HT and principle of light modulate of DMD are explained. DMD is controlled by programming to realize cyclic HT mask based on S-matrix. The performance of the mask is also verified by building a spectroscopy experiment system, and higher SNR spectrum information is acquired. The results indicate that the SNR in HT mode is 38.4323 while 11.3446 in scanning mode, the gain of SNR is 3.38. It can be concluded that the HT encoding mask that realized by DMD is feasible, spectrum signal’s intensity and SNR can be improved effectively.

A novel piezoelectrically actuated scanning micromirror integrated with angle sensors is presented. The mirror with large size of 3×3mm2 locates in the center of the device, and piezoelectric actuators are symmetrically placed on both sides of the mirror. They are connected through torsion bars in which piezoelectric angle sensors are integrated. In order to obtain large deflection angle at a low operation voltage, the new actuator consisting of several parallel piezoelectric cantilevers is adopted. The machematical models of the mirror and piezoelectric actuator are given, and the piezoelectric angle sensors are designed to obtain high sensitivities. The simulation results indicate that the maximum mechanical deflection angle of the micromirror is 12.4° at an operation voltage of 25V, and the maximum output voltage of the angle sensor is 164.3mV. The resonant frequency associated with the torsional mode is 960Hz. The sensitivity of the angle sensor is 13.3mV/° without amplifying. The Scanning miromirror is suitable for optical scanning systems such as the microscope, the micro-spectrometer, the medical imaging, the barcode reader and so on.

It is known that the wet chemical etching of silicon in alkaline solution has attracted wide attention due to its advantages such as lower cost, simpler setup, higher rate, smoother surface at micro level, higher degree of anisotropy, and lower pollution. In this paper, the key processes of fabricating vacuum microelectronic accelerometer and slits are presented. The cone curvature radius of the silicon tip arrays less than 30nm was fabricated with wet anisotropic etching of silicon in 33wt. % KOH solution at 70°C added potassium iodine (KI) and Iodine (I2) as additive and the cone aspect ratio was about 0.7. Smooth surface after etching in 33wt. %KOH solution added isopropyl alcohol (IPA) at 80°C was obtained and lateral etching was less than 5um after etching several hours for etching depth over 400um. Scalar slits with bottom width 25um and depth 500um were attained. A constant etch rate lead to precise and reproducible production. The test result reveals that the process to a specific occasion can reach practical requirements.

High mass resolution of sensors based on film bulk acoustic resonators (FBARs) is required for the detection of small molecules with the low concentration. An active control scheme is presented to improve the mass resolution of the FBAR sensors by adding a feedback voltage onto the driving voltage between two electrodes of the FBAR sensors. The feedback voltage is obtained by giving a constant gain and a constant phase shift to the current on the electrodes of the FBAR sensors. The acoustic energy produced by the feedback voltage partly compensates the acoustic energy loss due to the material damping and the acoustic scattering, and thus improves the quality factor and the mass resolution of the FBAR sensors. An explicit expression relating to the impedance and the frequency for an FBAR sensor with the active control is derived based on the continuum theory by neglecting the influence of the electrodes. Numerical simulations show that the impedance of the FBAR sensor strongly depends on the gain and the phase shift of the feedback voltage, and the mass resolution of the FBAR sensor can greatly be improved when the appropriate gain and the phase shift of the feedback voltage are used. The active control scheme also provides an effective solution to improve the resolution of the quartz crystal microbalance (QCM).

In this paper, a new four-electrode sensor for fresh water conductivity measurements is presented.The measurement system includes two parts: a four-electrode conductivity sensor unit and an integrated measuring circuit. The distribution of a four-electrode in electric field and the size of four electrodes are simulated by ANSYS - the MEMS simulation tool. The prototype of the conductivity sensor, with a four-electrode (each electrode is measuring 6mm×2mm or smaller), was fabricated on a PCB. The conductivity of a tested sample could be obtained according to output of the amplifier by calibrating the voltage of the conductivity of the standard liquid. The voltages of the conductivities, in the range from 0.34V to 9.00V, are detected by an oscillograph. This test result proves that it is promising to measure conductivity of fresh water utilizing the sensor based on the four-electrode system.

This paper presents a simple but reliable fabrication process for microfluidic devices on glass substrate using wet etching technology. Instead of using expensive Pyrex glasses as substrates and depositing expensive metal or polysilicon/amorphous silicon as etch masks in conventional method, glass slide is used as substrate and a single-layer negative photoresist RFJ-220 is used as the etching mask. The etch rates, generation of defects, undercut ratio and surface roughness are studied. In order to achieve high etching depth and smooth surface, buffered oxide etching with hydrochloric acid as additive is proposed. By proper cleaning and long-time hard baking, the undercut ratio can approach to 1. An 110μm depth microchannel with smooth surface is achieved. This fabrication process leads to a considerable reduction of process steps, fabrication time and material consumption. With this technique, we successfully fabricated a microfluidic device, which is used in the capture of hepatoma cells HepG2.

Multidisciplinary design optimization of a 2-D microaccelerometer is discussed. Considering the influence of microstructure design, fabrication process and detection circuit, as well as the constraints of fabrication limitations, damp design and adhesion factor, a multidisciplinary optimization model is developed by global criterion method, where the sensitivity, resolution, resonant frequency and damping ratio are selected as objective functions. Furthermore, the multi-objective optimum of the model is obtained by genetic algorithm.

Water quality monitoring plays an important role in contamination control and environment protection. This paper describes an on-line multiparametric water quality monitoring system based on visible spectrophotometry, which combines embedded technology with GPRS telecommunication technology. This system can realize online wireless monitoring to concentrations of chromium (Cr), plumbum (Pb), A surfactant (AS), chemical oxygen demand (COD), ammonia nitrogen (AN), total phosphorus (TP) and total phenol (TPh) in real time. The mechanical structure, hardware circuit and software design of the system are completed. The absorption spectrums of pure water and MB-SDS complex have been measured. Preliminary experiments using a model machine show that each mechanism of the system runs well. Moreover, the monitor possesses many advantages, such as high degree of automation, high reliability, high efficiency, compact structure, small size, and so on.

The stiffness of microstructure is an important parameter of the microsensor. It is usually obtained by FEM approach, which is difficult to give an analytical expression. This paper reports on a 2-D microaccelerometer with the complex microstructure. Its main axial stiffness is carried out by using force method as well as principle of work and strain energy. During the deduction, deformation of all beams is taken into account, so the theoretical results are in accordance with that of FEM approach very well and the error is less than one in thousand. Furthermore, we neither introduce the other assumptions nor design the special dimension. So this methodology is strict in theory, and can be extended to analysis for the displacement and stiffness of the symmetric and statically indeterminate microstructure.

In this study, the butyl methacrylate (BMA) monolithic column was proposed as a pretreatment functional part to integrate with microfluidic analytical system. The chemiluminescence (CL) of K 3 Fe(CN) 6 -NaOH-INH (isoniazid) was taken as the sample on the poly(methylmethacrylate) (PMMA) microchip for sample detection. Based on the optimum mixed ratios of chemiluminescence reagents, flow velocity of CL reagents, and washing eluents, the average enrichment of INH by BMA monolithic column reached 16.8, whereas the average recoveries were 84.2%. Making full use of the good extraction capacity of BMA monolith column, continuous operation of flow injection analysis, and high sensitivity of chemiluminescence detection, a new method for the detection of INH in plasma on the microchip was established. The INH in plasma could be directly pretreated and detected on the microchip with the methodology, and the detection limit was 0.2 mg l −1 .

Based on continuous spectrum analysis, the mathematical model for spectrum signal was established. And the spectrum signal's systematic error processing method based on the invariance of the ratio of the light intensities at any two wavelengths in the range of continuous spectrum was put forward. Combined with wavelet multi-resolution filtering noise processing techniques, the background interference processing method was established based on the spectral characteristics of the measured water quality parameter. These signal processing methods were applied to our independently developed multi-parameter water quality monitoring instrument to on-line measure COD (chemical oxygen demand), six valence chromium and anionic surfactant in the normative and actual environmental water samples, and the monitoring instrument had good repeatability (10%) and high accuracy (±10%) to meet the technical requirements of national environmental protection standards, which was verified by the contrast experiment with China national standard analysis method for determination of the three water quality parameter. The results showed that the researched signal processing methods were able to effectively reduce the spectrum signal's systematic error and the interference from noise and background, which was very important to improve the water quality monitoring instrument's technical function.

The method based on miniature near-infrared spectrometer combined with Y fiber optic probe to detect the protein and fat in milk powder by diffuse reflectance spectroscopy in the wavelength range of 900-1 700 nm was proposed. By selecting the appropriate spectral bands, the correction models of protein and fat were established with partial least squares algorithm using Unscrambler 9.7 Chemometrics software. The determination coefficients R2 of the correction modes are 0.987 and 0.986 for protein and fat respectively, and the root mean square errors RMSEC are 0.385 and 0.419 respectively. Using these correction models to predict the protein and fat contents with 30 sets of forecast sample data, the prediction standard deviation is SEP(Protein) = 0.751 for protein, and is SEP(Fat) = 1.109 for fat. The results indicate that these correction models have prediction capability with unknown samples and meet the on line requirements.

The water quality monitoring technology based on ultraviolet spectrum analysis has the characteristics of small volume, low cost, and no secondary pollution, and it doesn't need any reagent and sample pretreatment. On account of these characteristics, the direct ultra-violet technology has remarkable superiority over traditional technologies when applied in online monitoring of drinking water, surface water and industrial wastewater, and it has become an important development tendency of modern water monitoring technologies. The principle, characteristics, present situation and development trend of modern water quality monitoring technology based on ultra-violet spectrum analysis were introduced, and the key technical problems were further discussed in this paper.

On account of the high dimension and band overlapping features of the ultraviolet spectrum of complex wastewater, the relevance vector machine (RVM) algorithm combined with contiguous ultraviolet spectrum technology was applied in nitrate modeling to realize the rapid and accurate prediction of nitrate-nitrogen. At first the algorithm principle of RVM was introduced, and then based on the ultraviolet spectra of collected pharmacy effluent samples, ultraviolet absorption data between 230 and 245 nm were selected for modeling. Multivariate linear regression, partial least squares, classical support vector machines (SVM) and RVM methods were applied in nitrate modeling respectively and model performances were compared. Experimental result indicates that RVM method has advantages of higher prediction accuracy, sparser model than other compared methods and faster operation speed than SVM method. The relative full-range error is less than 4.5% F. S. Finally, it can be concluded that the LS-SVM method is effective in rapid and accurate detection of nitrate in practical wastewater with complicated composition.

A new method based on the weighted fusion of multiple models is presented for wavelength selection in multivariate calibration of spectral data. It fuses the regression coefficients of multiple models with weights based on minimum mean square error to improve the accuracy and stability of the wavelength selection. To validate the performance of the proposed method, it was applied to the partial least squares (PLS) modeling of three near-infrared spectral datasets and compared with full-spectrum PLS, genetic algorithm–based PLS, and uninformative variable elimination–based PLS methods. Results show that the proposed method can effectively select the informative wavelength and enhance the prediction ability of the PLS model. On account of its simpler algorithm and higher efficiency, it can be widely used in practical applications.

A homemade micro-spectrometer analytical system was developed for the quantitative determination of the sorbic acid in the food based on the photometric principle. And with the standard addition method it was applied to eliminate the interference coming from the food substrate. The detecting result illustrated a good relativity in the range of 0-10.0 mg x L(-1) with the linear correlation coefficient of 0.9989, and the sample recovery was 99.2%-99.5% with RSD of 0.58%. The micro-spectrometer analysis system has shown potential prospective application in the fields of rapid and high performance detection for food additives.

Aiming at the monitoring and protecting of water resource environment, a multi-parameter water quality monitoring microsystem based on microspectrometer was put forward in the present paper. The microsystem is mainly composed of MOEMS microspectrometer, flow paths system and embedded measuringcontrolling system. It has the functions of self-injecting samples and detection regents, automatic constant temperature, self -stirring, self- cleaning and samples' spectrum detection. The principle prototype machine of the microsystem was developed, and its structure principle was introduced in the paper. Through experiment research, it was proved that the principle prototype machine can rapidly detect quite a few water quality parameters and can meet the demands of on-line water quality monitoring, moreover, the principle prototype machine has strong function expansibility.

Ultraviolet-spectrum technology is a kind of low signal and multianalysis technology. For taking full advantage of spectral information and reducing the volume of spectrometer, we used high efficiency spectroscopy structure based on concave grating. Based on concave grating theory and optic design software ZEMAX, a flat field concave grating for ultraviolet spectrophotometer was designed from primary structure, which relied on global optimization of the software. The contradiction between wide spectrum bound and limited spectrum extension was resolved, aberrations were reduced successfully, spectrum information was utilized fully, and the optic structure of spectrometer was highly efficient. For better preference of this spectrophotometer, after get the structure parameter, combine grating fabrication condition with practice working condition, grating diffractive theory, holographic optics theory and software PCG rate was used for diffraction efficiency design and improve. A paradigm of flat field concave grating is given, it works between 190 nm to 410 nm, the diameter of the concave grating is 20 mm, and F/# is 0.21. The design result was analyzed and evaluated. It was showed that if the slit source, whose width is 50 microm, is used to reconstruction, the theoretic resolution capacity is better than 3 nm.

Phenol and anionic surfactant are important indices for water-quality. Based on improvement and optimization of standard methods (spectrophotometry) for the two indices, we integrated the respective two color-extractants into a composited reagent. Using a self-developed microspectrometer with a design of splitting behind and collection of continuous spectrum signal (340-770 nm) in real time, a compound detection system was constructed. This system could simultaneously detect phenol and anionic surfactant in water without chemical and spectral interferences, leading to great decreases in reagent amount and detection time. The detection limits for phenol and anionic surfactant are 0. 003 and 0.016 mg x L(-1), respectively. This method was applied to water-quality monitoring of real samples in comparison with standard methods, and the results indicated that its reproducibility (relative standard deviation, n=5) and accuracy (relative error to results by standard methods) were less than 5%, contenting with the related standard.

According to the requirements of rapid detection of important life parameters for the sick and wounded, a new micro bio-chemical detection configuration was proposed utilizing continuous spectroscopy analysis, which was founded on MOEMS and embedded technology. The configuration was developed as so much research work was carried out on the detecting objects and methods. Important parameters such as stray light, absorbance linearity, absorbance ratability, stability and temperature accuracy of the instrument were tested, which are all in good agreement with the design requirements. Clinic tests show that it can detect multiple life parameters quickly (Na+, GLU, Hb eg.).

A MOEMS micro-mirror spectrometer, which uses micro-mirror as a light switch so that spectrum can be detected by a single detector, has the advantages of transforming DC into AC, applying Hadamard transform optics without additional template, high pixel resolution and low cost. In this spectrometer, the vital problem is the conflict between the scales of slit and the light intensity. Hence, in order to improve the resolution of this spectrometer, the present paper gives the analysis of the new effects caused by micro structure, and optimal values of the key factors. Firstly, the effects of diffraction limitation, spatial sample rate and curved slit image on the resolution of the spectrum were proposed. Then, the results were simulated; the key values were tested on the micro mirror spectrometer. Finally, taking all these three effects into account, this micro system was optimized. With a scale of 70 mm x 130 mm, decreasing the height of the image at the plane of micro mirror can not diminish the influence of curved slit image in the spectrum; under the demand of spatial sample rate, the resolution must be twice over the pixel resolution; only if the width of the slit is 1.818 microm and the pixel resolution is 2.2786 microm can the spectrometer have the best performance.

A method which uses MOEMS mirror array optical structure to reduce the high cost of infrared spectrometer is given in the present paper. This method resolved the problem that MOEMS mirror array can not be used in simple infrared spectrometer because the problem of imaging irregularity in infrared spectroscopy and a new structure for spectral imaging was designed. According to the requirements of imaging spot, this method used optical design software ZEMAX and standard-specific aberrations of the optimization algorithm, designed and optimized the optical structure. It works from 900 to 1 400 nm. The results of design analysis showed that with the light source slit width of 50 microm, the spectrophotometric system is superior to the theoretical resolution of 6 nm, and the size of the available spot is 0.042 mm x 0.08 mm. Verification examples show that the design meets the requirements of the imaging regularity, and can be used for MOEMS mirror reflectance scan. And it was also verified that the use of a new MOEMS mirror array spectrometer model is feasible. Finally, analyze the relationship between the location of the detector and the maximum deflection angle of micro-mirror was analyzed.

TaNHX2, a vacuolar Na+-H+ antiport gene from wheat (Triticum aestivum L.), was transformed into alfalfa (Medicago sativa L.) via Agrobacterium-mediated transformation to evaluate the role of vacuolar energy providers in plant salt stress responses. PCR and Southern blotting analysis showed that the target gene was integrated into the Medicago genome. Reverse transcription-PCR indicated that gene TaNHX2 was expressed at the transcriptional level. The relative electrical conductivity in the T2 transgenic plants was lower and the osmotic potential was higher compared to the wild-type plants under salt stress conditions. The tonoplast H+-ATPase, H+-pyrophosphatase (PPase) hydrolysis activities and ATP-dependent proton pump activities in transgenic plants were all higher than those of wild-type plants, and the enzyme activities could be induced by salt stress. The PPi-dependent proton pump activities decreased when NaCl concentrations increased from 100mM to 200mM, especially in transgenic plants. The vacuolar Na+-H+ antiport activities of transgenic plants were 2-3 times higher than those of the wild -type plants under 0mM and 100mM NaCl stress. Na+-H+ antiport activity was not detectable for wild-type plants under 200mM NaCl, but for transgenic plants, it was further increased with an increment in salt stress intensity. These results demonstrated that expression of the foreign TaNHX2 gene enhanced salt tolerance in transgenic alfalfa.

The application of spectral analysis to water quality monitoring is an important developing trend in the field of modern environment monitoring technology. The principle and characteristic of water quality monitoring technology based on UV-Vis spectrum analysis are briefly reviewed. And the research status and advances are introduced from two aspects, on-line monitoring and in-situ monitoring. Moreover, the existent key technical problems are put forward. Finally, the technology trends of multi-parameter water quality monitoring microsystem and microsystem networks based on microspectrometer are prospected, which has certain reference value for the research and development of environmental monitoring technology and modern scientific instrument in the authors' country.

Aiming at application of micro-spectrometer systems, a novel electromagnetically actuated MEMS scanning mirror with large size and integrated rotation angle sensor is proposed for the application of micro-spectrometer. The size of the mirror plate is 6x5mm 2 , which is supported by two torsion beams. The scanning mirror is fabricated on a 500 μm-thick single crystal silicon wafer using bulk micromachining process. Two gold coils are deposited on back side of the mirror using electroplating technology. One of them is used to generate Lorentz force to drive the mirror, and the other is used to monitor the rotation angle by measuring the induced voltage which is proportional to the angular rate. The silicon substrate is heavily doped (0.02 ohm•cm) to connect the coil central end to outside pad. A 500 nm-thick aluminum film is sputtered on the front side of the mirror plate to form a high quality mirror surface. The whole structure is released by wet etching technology, and corner compensation structure is designed to avoid convex corner undercutting. In order to achieve large deflection angle, NdFeB permanent magnets are used to provide high magnetic field. Testing results show that maximum mechanical rotation angle of the scanning mirror can achieve ±10°at the resonant frequency of 344Hz with low driving voltage of less than 1Veff, corresponding to a Q-factor of 137 at atmospheric pressure, and the output voltage of the angle sensor has high linearity.

A novel design for fabricating the high efficacious rectangular phase grating with angle sensor by MOEMS fabrication process is presented in this paper. The purpose of this design is for increasing the Signal-to-Noise of output signal and reducing the size of near infrared spectrometer by using MOEMS grating. Diffraction efficiency is designed and optimizing at first. We used Fourier optical theory and diffraction optical theory analyzed the diffraction efficiency of the rectangular phase grating, and used the PCgrate simulated the design. After analysis and calculation, we found the best parameter of this grating. According the former design of infrared spectrometer by ZEMAX, the angle resolution of angle sensor is 60mV/°, maximal angle is ±4.7° and the size of grating is 5x6mm 2 . Because of the large deflection angle, the electromagnetic force is used for driving this grating. For sensing the grating deflexion angle, we design the angle sensor in the torsion bar of this grating. This sensor is P-type piezoresistive sensor and fabricated on n-(100) high-resistance silicon wafer by boron ion implantation. Analyses stress of torsion bar and piezoresistive angle sensor with Wheatstone bridge theory, the scanning angle θ in a linear relation with output voltages (V out ) of Wheatstone bridge. The size of torsion bar is 2100μmx220μmx75μm, the frequency of first step model is 550Hz. The size of the sensor is 100μmx15μmx0.5μm. Finally, the compatible fabrication process of this device is given. The results of experiments and theory analyzing demonstrate that MOEMS phase grating could work effectively, and angle sensor achieve the real time need. This MOEMS grating is suitable for infrared spectrometer.

A novel micro-ultraviolet spectrometer system with characteristics of small size, low price and high performance was developed and the main performance parameters were tested. The wavelength range is 190-410nm, the wavelength accuracy is less than 1nm, and the resolution is less than 3nm (using 100um fiber). To verify the system performance, a pollution-free water quality testing platform was built based on the micro-ultraviolet spectrometer and experiments of chemical oxygen demand (COD) testing were made. The results indicated that the system performance can meet the practical demands of real-time water quality monitoring.

Infrared (IR) spectrometers are very important optical equipments that can be used in industry, science, medicine, agriculture, biology and food safety etc., and the market is growing. However, most traditional IR spectrometers, such as Fourier transform spectrometer (FTS) that based on Michelson interferometer principle and scanning monochromator that based on grating scanning, are expensive, relative large volume, and stationary, which can't meet the requirements of specific application such as rapidity, special environment and some special samples. To overcome these drawbacks, innovatory technology-micro electro mechanical systems (MEMS) technology was used in micro IR spectrometers in the past few years. And several prototypes and products that based on several operational principles have been emerged. In this paper, a novel IR micro spectrometer which based on MEMS technology and used single element detector was presented over a wide spectral range (from 2500nm to 5000nm) in the mid infrared (MIR) wavelength regime, and the optical system of it was designed on the basis of traditional scanning monochromator principle. In the optical system, there is a highlighted characteristic that dual spherical focus mirror was used to focus the diffraction light of the diffraction grating, which improved the spectral resolution of the optical system. Finally, using Zemax optical software, three torsion angle locations were selected to simulate the optical system of the spectrometer with the slit's size 0.1mm×1mm. The simulation result indicated that in the whole wavelength range the spectral resolution of the optical system was less than 30nm, and a high accuracy MIR spectrometer with compact volume will be realized in future hopefully.

Quantum cascade laser (QCL) is an ideal mid-infrared source for gas sensing in the wavelength range from 2.5 to 25 microm, due to its fast response, high sensitivity and selectivity for gas detecting. Prototypes of gas sensing system based on QCL have been developed by worldwide research groups. They have great potential in many applications, such as environment monitoring, space exploration, anti-terrorism and so on. The present paper gives a broad review of QCL gas sensing system, including the basic working principle, existing systems, and its application and future development.

NIR spectroscopy makes a feature of a large number of wavelengths with a much smaller set of samples. However, some of the wavelengths contribute no information to the modeling. Even worse, they may contain the irrelevant information such as noise and background, which may result in a complex model and/or bad predictive ability of the model. So, it's important to do research in-depth to eliminate these wavelengths and improve the quality of the final model. The present paper firstly summarizes the variable selection methods based on a single PLS regression model and concludes that (1) the cross-validation can be used to select optimal model with good predictive ability, but the resulting model may be not suitable for selecting variables; (2) selecting variables based on a single regression model is inaccurate and instable because a single vector of regression coefficients may not measure the importance of the variables correctly and may vary with models of different complexity. On basis of this analysis, this paper proposed a new method for variable selection based on the fusion of multiple PLS models. This method fuses the multiple PLS regression coefficients to form a vector, then a threshold is determined to eliminate the variables whose corresponding element in the vector is lower than this threshold. Finally, this method is verified by 3 well-known NIR datasets and compared with the UVE-PLS and GA-PLS algorithms. The experiments show that this method may result in a model with less complexity and/or better predictive ability. Moreover, the proposed method is elegant and efficient and therefore can be put in practical use.