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Lv J.,Supreme Technology | Zhang L.,National Marine Environmental Monitoring Center | Feng J.,Supreme Technology | Liu Y.,Supreme Technology | And 3 more authors.
Spectroscopy Letters | Year: 2011

Optical observation of lung cancer tissues using attenuated total reflectance-Fourier transform infrared microscope (ATR-FTIR) and confocal Raman microscope were performed. A total of six malignant tissues, seven tissues adjacent to cancer, and nine normal tissues from nine patients with known lung cancer were studied. High-quality spectra from human tissues were obtained only in a few seconds. The results revealed that some of the spectral characteristics varied significantly between normal and malignant tissues, that is, IR peak positions, Raman shift, and the spectral intensities. Differences in positions of 10 main peaks in IR shifts and 13 main peaks in Raman shifts were listed, and the intensity changes were also studied between the malignant and normal tissues. The ratios of 1453-cm-1/1645-cm-1 intensity in IR spectrum and 1245-cm-1/1571-cm-1 intensity in Raman spectrum were found with the most significant difference (p<0.0001 and p<0.05 separately) in statistics and may be used in combination to differentiate the normal and malignant tissues. ATR-FTIR spectrum and Raman spectrum were mutually complementary in the observation of many materials and were both found with high sensitivities and spatial resolutions in the observation of human tissues. This study will be helpful to developing rapid and accurate cancer detection techniques in future clinical diagnosis. Copyright © Taylor & Francis Group, LLC. Source

Zhang W.,Shandong Academy of Sciences | Zhang W.,Nankai University | Lv J.,Supreme Technology | Shi R.,Agro Environment Monitoring Center | Liao C.,CAS Yantai Institute of Coastal Zone Research
Soil and Sediment Contamination | Year: 2012

A rapid screening method using microwave-assisted extraction (MAE) in combination with gas chromatography and mass spectrometry for the determination of 70 pesticide residues in soil was established. The pesticides included 27 organophosphorus pesticides (OPPs), 29 organochlorine pesticides (OCPs), nine pyrethroids, and five carbamates. Parameters that could affect the efficiency of extraction, such as temperature, time, and solvent, were investigated. The condition of the extraction, under which recoveries of all 70 pesticides ranged from 70% to 120%, was optimized with a 1:1 (V/V) mixture of acetone and hexane, a temperature of 100°C, and an extraction time of 10 min. All compounds studied could be recovered in good yields and with relative standard deviations (RSDs) lower than 20%. The linearity of the method for all the pesticides was greater than 0.99 over a concentration range of 0.1-5 μg/g. The detection limits varied from 0.5 to 211.25 ng/g. Interday and intraday precision analyses yielded RSDs of 1.2%-11.7% and 3.6%-15.1%, respectively. This method, which was as effective as Soxhlet extraction and accelerated solvent extraction (ASE), proved to be accurate and precise. When the proposed method was used to examine environmental samples, the obtained results were in good agreement with those obtained using Soxhlet extraction. © 2012 Copyright Taylor and Francis Group, LLC. Source

Lv J.,Supreme Technology | Feng J.,Supreme Technology | Liu Y.,Supreme Technology | Wang Z.,Supreme Technology | And 2 more authors.
Analytical Letters | Year: 2012

The analysis of automotive coatings is important to forensic scientists, especially in the investigation of hit-and-run accidents. Amino resin paints, alkyd resin paints, and polyurethane paints are all popular automotive coatings. In this study, FTIR was employed to investigate these coatings, particular in amino resin paints. IR spectra were tentatively interpreted. The indicative peaks distinguishing amino resin paints (1550 cm-1) and alkyd resin paints (1600 cm-1/1580 cm-1) were summarized. Two kinds of alkyd resin paints (with the Pigment Scarlet Powder and with the Toluidine Red), which were frequently confronted in cases and might readily be read as amino resin paints in IR spectra, were studied and interpreted. The indicative peaks (1619 cm-1, 776 cm-1 and 1674 cm-1, 1494 cm-1) were selected to discriminate these two kinds of alkyd resin paints from amino resin paints and avoid an incorrect certificate of authenticity. The data in this study can help the forensic scientists identify these three paints accurately, especially in the cases with the interference of the pigments. © 2012 Copyright Taylor and Francis Group, LLC. Source

Lv J.,Supreme Technology | Feng J.,Supreme Technology | Liu Y.,Supreme Technology | Wang Z.,Supreme Technology | And 3 more authors.
Spectroscopy (Santa Monica) | Year: 2012

The analysis of automotive coatings is important for forensic scientists in the investigation of hit-and- run accidents. However, many kinds of paint are similar in structure and cannot be discriminated easily. In this study, Fourier-transform infrared (FT-IR) and Raman microscopy were employed to investigate different kinds of clay as the additives in paints to help discriminate the paints. The IR and Raman spectra were measured and tentatively interpreted. The indicative peaks distinguishing kaolin and bentonite were summarized in the IR spectrum. For some other kinds of clay that could not be discriminated from kaolin in the IR spectrum, several peaks in the Raman spectrum of kaolin were found to be weak but characteristic as indicators of kaolin. The method was applied and verified in a complex paint analysis case successfully. The data in this study can help forensic scientists identify paints accurately, particularly in cases with interference in the spectrum (<3000 cm1). Source

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