An anti-passivation ink for the preparation of electrodes for use in electrochemical immunoassays.

p-Nitrophenylphosphate (PNPP) is usually employed as the substrate for enzyme-linked immunosorbent assays. p-Nitrophenol (PNP), the product of PNPP, with the catalyst alkaline phosphatase (ALP), will passivate an electrode, which limits applications in electrochemical analysis. A novel anti-passivation ink used in the preparation of a graphene/ionic liquid/chitosan composited (rGO/IL/Chi) electrode is proposed to solve the problem.

[Evaluation of Sugar Content of Huanghua Pear on Trees by Visible/Near Infrared Spectroscopy].

A method of ambient light correction was proposed to evaluate the sugar content of Huanghua pears on tree by visible/near infrared diffuse reflectance spectroscopy (Vis/NIRS). Due to strong interference of ambient light, it was difficult to collect the efficient spectral of pears on tree. In the field, covering the fruits with a bag blocking ambient light can get better results, but the efficiency is fairly low, the instrument corrections of dark and reference spectra may help to reduce the error of the model, however, the interference of the ambient light cannot be eliminated effectively.

The relationship of spectral sensitivity with growth and reproductive response in avian breeders (Gallus gallus).

A previous study demonstrated that birds that are exposed to light at night develop advanced reproductive systems. However, spectrum might also affect the photoperiodic response of birds. The present study was aimed to investigate the effects of spectral composition on the growth and reproductive physiology of female breeders, using pure light-emitting diode spectra.

[Quantitative analysis of goose and duck mixed down using visible/NIR spectroscopy].

Goose down and duck down have very similar appearance but the quality of goose down is better than that of duck down in general. There is a highest allowable limit as specified by the various national standards of feather and down for the percentage of duck feather or down mixed in goose feather or down. Traditional detection method, manual inspection with a high-scale microscope, is labor intensive and not suitable for large-volume samples analysis and on-site rapid testing.

[Application of hyperspectral fluorescence image technology in detection of early rotten oranges].

Rottenness is most prevalent and devastating disease that threats citrus fruit. Automatic detection of early rottenness can enhance the competitiveness and profitability of the citrus industry. However, there is no efficient automatic detection technology at this time that could detect this disease.

[Rapid detection of Escherichia coli O157 : H7 using surface plasmon resonance (SPR) biosensor].

A biosensor based on surface plasmon resonance (SPR) was developed for rapid detection of Escherichia coli O157 : H7. BIACORE 3000 SPR instrument and a dextran-modified sensor chip (CM5) were used. After activation with EDC/NHS, anti-E.

[Advance on application of hyperspectral imaging to nondestructive detection of agricultural products external quality].

Hyperspectral imaging is an emerging technique that integrates conventional imaging and spectroscopy to obtain both spatial and spectral information from a studied object simultaneously. The images data can reflect the external features, surface defects and contamination. The spectra data can analyze physical structure and chemical composition in studied object.

[Research on the trash content measurement and classification of ginned cotton by using NIR spectroscopy technique].

Near infrared (NIR) spectroscopy was investigated to predict trash content and classify types of ginned cotton by using a fiberoptic in diffuse reflectance mode. Different spectra preprocessing methods were compared, and partial least-squares (PLS) regression was established to predict the trash content of ginned cotton. Discriminant analysis (DA) was used to classify various types of lint and content level of trash.

[Applications of atomic emission spectrum from liquid electrode discharge to metal ion detection].

The fast and precise detection of metal ion is an important research project concerning studies in diverse academic fields and different kinds of detecting technologies. In the present paper, the authors review the research on atomic emission spectrum based on liquid electrode discharge and its applications in the detection of metal ion. In the first part of this paper the principles and characteristics of the methods based on electrochemistry and spectroscopy were introduced.

[Qualitative analysis of fragrant pear class based on near infrared diffuse reflectance spectroscopy].

A method was developed to automatically discriminate the persistent calyx fruit and fruit without calyx of fragrant pear by means of near infrared spectroscopy (NIRS). The prediction performance of different band regions range, different principal component numbers and different preprocessing methods of the spectra (multiplicative signal correction, standard normal variate, and derivative spectra) together with discriminant analysis (DA) was also investigated, and The calibration model was established to classify the different kinds of fragrant pear. The research results for the fragrant pear classification showed that DA calibration models using these parameters with band regions between 9 091 and 4 000 cm(-1) and original spectra are optimal, with the percentage of correct sample classification being 100% and 95% for the calibration and validation set, respectively.

[Application of immunomagnetic separation to E. coli O157 : H7 detection].

In the present paper, the capture efficiencies of four different proportions of E. coli O157 : H7 and immunomagnetic beads (IMB) (1 : 6.34, 1 : 12.

[Application of near-infrared spectroscopy to detection of pesticide phoxim residues].

Near-infrared (NIR) spectroscopy technique was applied directly to the detection of pesticide phoxim residues. A sample pretreatment method was introduced. Samples were mixed with silica gel.

[Advance in nondestructive detection of fruit internal quality based on hyperspectral imaging].

The present paper reviews the development in the field of hyperspectral imaging technology for nondestructive detection of fruit internal quality in recent years up to the year 2007. With the increasing maturity of hyperspectral imaging technology, decline of cost for its hardware and software, and improvement in hyperspectral image data processing algorithms, hyperspectral imaging technology for fruit quality nondestructive detection has become a hot research topic. In order to track the latest research developments at home and abroad, the fruit internal quality (maturity, firmness, soluble solid content, water content) detection with hyperspectral imaging was reviewed, which would provide reference for Chinese researchers.

[Study on Vis/NIR spectra detecting system for watermelons and quality predicting in motion].

To make Vis/NIR diffuse transmittance technique applied to quality prediction for watermelon in motion, the dynamic spectra detecting system was rebuilt. Spectra detecting experiments were conducted and the effects of noises caused by motion on spectra were analyzed. Then the least--square filtering method and Norris differential filtering method were adopted to eliminate the effects of noise on spectra smoothing, and statistical models between the spectra and soluble solids content were developed using partial least square method.

[Applications of terahertz spectroscopy and imaging techniques in food safety inspection].

With the development of ultra-fast laser technology and the further understanding of the mechanism behind the interaction of terahertz radiation and materials, THz radiation is actively developed as a new-style technology for a wide range of applications. Currently THz spectroscopy and imaging techniques show great promise in security detection, medical diagnosis, wireless communication, pharmaceutical and many other areas. Because of the growing importance of food safety issues, the detection technology of food safety is also faced with great opportunities and challenges, while THz spectroscopy and imaging techniques provide a new solution to the problem.

[Application and recent development of research on near-infrared spectroscopy for meat quality evaluation].

As one of new optical detection methods, near-infrared spectroscopy (NIRS) technique has been widely used in food industry in recent years. NIRS technique is also promising for quality evaluation of meat and meat products and is characterized by its quickness, online operation and nondestructive detection. The present paper reviews the main application and recent development of research on near-infrared spectroscopy in meat industry, including components analysis, sensory quality evaluation as well as discrimination of production.

[Effect of pathlength variation on the NIR spectra for quality evaluation of chinese rice wine].

Near infrared (NIR) spectroscopy and chemometrics were applied to determine the effect of pathlength variation on the spectra of the Chinese rice wine and the consequences of the prediction precision of calibration models developed for measuring alcoholic degree, sugar content, and pH was investigated in the present research Samples were scanned in transmission mode using a commercial FT-NIR spectrometer and a demountable liquid cell for versatile path length liquid sampling. By comparing the results of performance between models based on different optical pathlength (0.5, 1, 1.

[Study on classification of ethylene treated and non-ethylene treated watermelons by visible/near infrared spectroscopy].

According to the fact that farmers often picked unripe watermelon and treated them with high concentration ethylene to quicken ripeness, classification experiments on the two classes of watermelon mentioned above were conducted based on the Vis/NIR spectroscopy diffuse transmittance technique. In the discriminant analysis, a method to classify them by diffuse transmittance ration at two wavelengths was adopted to discriminate them. Result of mistake ratio 32.

[NIR spectroscopy based on least square support vector machines for quality prediction of tomato juice].

The application of least square support vector machines (LS-SVM) regression method based on statistics study theory to the analysis with near infrared (NIR) spectra of tomato juice was introduced in the present paper. In this method, LS-SVM was used for establishing model of spectral analysis, and was applied to predict the sugar contents (SC) and available acid (VA) in tomato juice samples. NIR transmission spectra of tomato juice were measured in the spectral range of 800-2,500 nm using InGaAs detector.

Use of near-infrared spectroscopy and least-squares support vector machine to determine quality change of tomato juice.

Near-infrared (NIR) transmittance spectroscopy combined with least-squares support vector machine (LS-SVM) was investigated to study the quality change of tomato juice during the storage. A total of 100 tomato juice samples were used. The spectrum of each tomato juice was collected twice: the first measurement was taken when the tomato juice was fresh and had not undergone any changes, and the second measurement was taken after a month.

[Identification of tea from different regions using X-ray fluorescence].

The existence of fake tea from non-origin seriously impacts on the credibility of the famous tea. A method was developed to identify tea from difference regions on the basis of the fact that the content of heavy metals in different origin tea is varied by using X-ray fluorescence technique and pattern recognition technique. Samples from different origins were grouped respectively, and their X-ray fluorescence spectra were acquired, and then the principal components of these spectral data were calculated, and the average of the principal components of each group was used as the center of each group.

[Studies on detection of E. coli O157:H7 by ATP bioluminescence].

In the present paper, a quantitative linear model betweena series of concentrations of E. coliO157 : H7 and counts by BPCL ultra weak luminescence analyzer was built up. And the influences of four different buffers with the same pH (pH = 7.

[Progress in application of near infrared spectroscopy to nondestructive on-line detection of products/food quality].

Increasing safety events caused by products/food quality problems has caught more and more attention, therefore non-destructive fast detection of products/food quality becomes necessary. At present, fast detection methods commonly used include chemical colorimetric method, near infrared spectroscopy (NIRS) technique, immunoassay method, bio-sensor technique, biomicroarray method, bioluminescence method, and so on. NIRS technique has found wide application in products/food quality detection because of its characteristics such as very high speed, no sample preparation, non-destruction, no pollution, low cost etc.

[Visible/NIR analysis of fat, protein and water in chilled pork].

Fat, protein and water were determined by visible and NIR transmittance spectroscopy in chilled pork. After preprocessed by multiplicative scatter correction (MSC), the quantitative analysis models were developed based on the original, first derivative and second derivative spectra by using partial least squares (PLS) at the temperatures of 0-4 degrees C and 20 degrees C, respectively. By comparing the correlation coefficient (r), RMSEC, and SEP, we found that the first derivative model was the best, and the performance for 0-4 degrees C was better than that for 20 degrees C.

[Online detection of soluble solids content of pear by near infrared transmission spectrum].

The research was to detect soluble solids content (SSC) of pear online by near infrared transmission spectrum. The movement speed of pear was 0.5 m x s(-1) the power of light source was 300 W, and semi-transmission was used to collect the spectrum of pears.