Journal of Spectroscopy The latest articles from Hindawi Publishing Corporation © 2014 , Hindawi Publishing Corporation . All rights reserved. Characterization of Polysaccharide by HPLC: Extraction and Anticancer Effects Wed, 03 Sep 2014 00:00:00 +0000 Cervical cancer is a serious health hazard for women’s reproductive system cancer; the method of treatment for cervical cancer is still in surgery, chemotherapy, and radiotherapy as the basic means, but with many complications. The effects of natural medicines for cervical cancer are increasingly becoming the focus of people’s attentions. By studying the polysaccharide of cervical cancer in mice, we found that shark cartilage polysaccharide can increase the serum levels of T-SOD and GSH and decrease MDA level significantly in the tumor mice. The distribution of the drug in the tissue was determined by HPLC method; the drug can be drawn in the liver and kidney the highest, followed by the spleen, lung, and brain levels being the lowest. Polysaccharide can inhibit tumor growth in the mice which may be connected with the enhanced immunity and the antioxidant capacity. Liming Gao, Ya Di, Jiandong Wu, Ming Shi, and Fulu Zheng Copyright © 2014 Liming Gao et al. All rights reserved. Preparation and Aromatic Hydrocarbon Removal Performance of Potassium Ferrate Tue, 02 Sep 2014 09:10:27 +0000 This experiment adopts the hypochlorite oxidation method to constantly synthesize potassium ferrate. Under the condition of micropolluted source water pH and on the basis of naphthalene, phenanthrene, and pyrene as research objects, the effects of different systems to remove aromatic hydrocarbons were studied. Various oxidation systems to remove phenanthrene intermediate are analyzed and the detailed mechanisms for removal of phenanthrene are discussed. The study found that the main intermediate of potassium ferrate system to transform phenanthrene is 9,10-phenanthraquinone and its area percentage reached 82.66%; that is, 9,10-phenanthraquinone is the key entity to remove phenanthrene. Wei Guan, Zhigang Xie, and Jia Zhang Copyright © 2014 Wei Guan et al. All rights reserved. Experimental Study of the Composition and Structure of Granular Media in the Shear Bands Based on the HHC-Granular Model Sun, 31 Aug 2014 06:32:58 +0000 The researchers cannot control the composition and structure of coarse grained soil in the indoor experiment because the granular particles of different size have the characteristics of random distribution and no sorting. Therefore, on the basis of the laboratory tests with the coarse grained soil, the HHC-Granular model, which could simulate the no sorting and random distribution of different size particles in the coarse-grained soil, was developed by use of cellular automata method. Meanwhile, the triaxial numerical simulation experiments of coarse grained soil were finished with the different composition and structure soil, and the variation of shear strength was discussed. The results showed that the internal friction angle was likely to reduce with the increasing of gravel contents in the coarse-grained soil, but the mean internal friction angle significantly increased with the increment of gravel contents. It indicated that the gravel contents of shear bands were the major factor affecting the shear strength. Guang-jin Wang, Xiang-yun Kong, and Chun-he Yang Copyright © 2014 Guang-jin Wang et al. All rights reserved. Insights into the Synergistic Effect of Fungi and Bacteria for Reactive Red Decolorization Sun, 10 Aug 2014 11:32:49 +0000 Bacterial contamination is a prevalent problem in fungal dye wastewater decolorization that prevents the development of this technology in practical engineering. New insight into the relationship between fungi and bacteria is given in terms of settleability, bioadsorption, and biodegradation, which all confirm their synergistic effect. Sterilization is implied to be not the only mechanism for fungi decolorization. When the fungi and bacteria isolated from the activated sludge were cocultured, fungi removed more than 70% of the reactive red through sole bioadsorption in 5 min and enhanced the settleability of the bacteria group from 7.7 to 18.4 in the aggregation index. Subsequently, the bacteria played a more significant role in dye biodegradation according to the ultraviolet-visible spectrum analysis. They further enhanced the decolorization efficiency to over 80% when cocultured with fungi. Therefore, the advanced bioadsorption and settleability of fungi, combined with the good dye biodegradation ability of bacteria, results in the synergistic effect of the coculture microorganisms. Dandan Zhou, Xueying Zhang, Yilin Du, Shuangshi Dong, Zhengxue Xu, and Lei Yan Copyright © 2014 Dandan Zhou et al. All rights reserved. Characterization of Binary Organogels Based on Some Azobenzene Compounds and Alkyloxybenzoic Acids with Different Chain Lengths Sun, 10 Aug 2014 11:31:29 +0000 In this work the gelation behaviors of binary organogels composed of azobenzene amino derivatives and alkyloxybenzoic acids with different lengths of alkyl chains in various organic solvents were investigated and characterized. The corresponding gelation behaviors in 20 solvents were characterized and shown as new binary organic systems. It showed that the lengths of substituent alkyl chains in compounds have played an important role in the gelation formation of gelator mixtures in present tested organic solvents. Longer methylene chains in molecular skeletons in these gelators seem more suitable for the gelation of present solvents. Morphological characterization showed that these gelator molecules have the tendency to self-assemble into various aggregates from lamella, wrinkle, and belt to dot with change of solvents and gelator mixtures. Spectral characterization demonstrated different H-bond formation and hydrophobic force existing in gels, depending on different substituent chains in molecular skeletons. Meanwhile, these organogels can self-assemble to form monomolecular or multilayer nanostructures owing to the different lengths of due to alkyl substituent chains. Possible assembly modes for present xerogels were proposed. The present investigation is perspective to provide new clues for the design of new nanomaterials and functional textile materials with special microstructures. Yongmei Hu, Qingshan Li, Wei Hong, Tifeng Jiao, Guangzhong Xing, and Qilong Jiang Copyright © 2014 Yongmei Hu et al. All rights reserved. Standoff Methods for the Detection of Threat Agents: A Review of Several Promising Laser-Based Techniques Thu, 07 Aug 2014 06:53:43 +0000 Detection of explosives, explosive precursors, or other threat agents presents a number of technological challenges for optical sensing methods. Certainly detecting trace levels of threat agents against a complex background is chief among these challenges; however, the related issues of multiple target distances (from standoff to proximity) and sampling time scales (from passive mines to rapid rate of march convoy protection) for different applications make it unlikely that a single technique will be ideal for all sensing situations. A number of methods for spanning the range of optical sensor technologies exist which, when integrated, could produce a fused sensor system possessing a high level of sensitivity to threat agents and a moderate standoff real-time capability appropriate for portal screening of personnel or vehicles. In this work, we focus on several promising, and potentially synergistic, laser-based methods for sensing threat agents. For each method, we have briefly outlined the technique and report on the current level of capability. J. Bruce Johnson, Susan D. Allen, Jonathan Merten, Lewis Johnson, Daniel Pinkham, and Scott W. Reeve Copyright © 2014 J. Bruce Johnson et al. All rights reserved. Anthracene Fluorescence Quenching by a Tetrakis (Ketocarboxamide) Cavitand Wed, 06 Aug 2014 06:09:06 +0000 Quenching of both fluorescence lifetime and fluorescence intensity of anthracene was investigated in the presence of a newly derived tetrakis (ketocarboxamide) cavitand at various concentrations. Time-correlated single photon counting method was applied for the lifetime measurements. A clear correlation between the fluorescence lifetime of anthracene as a function of cavitand concentration in dimethylformamide solution was observed. The bimolecular collisional quenching constant was derived from the decrease of lifetime. Fluorescence intensity was measured in the emission wavelength region around 400 nm as a result of excitation at 280 nm. Effective quenching was observed in the presence of the cavitand. The obtained Stern-Volmer plot displayed upward curvature. The results did not follow even extended Stern-Volmer behavior, often used to describe deviations from static bimolecular quenching. To explain our results we adopted the Smoluchowski model and obtained a reasonable estimate for the molecular radius of the cavitand in solution. Tibor Zoltan Janosi, Jouko Korppi-Tommola, Zsolt Csok, Laszlo Kollar, Pasi Myllyperkio, and Janos Erostyak Copyright © 2014 Tibor Zoltan Janosi et al. All rights reserved. Use of Novel Polyurethane Microspheres in a Curcumin Delivery System Mon, 04 Aug 2014 08:29:07 +0000 Despite having a wide range of beneficial pharmacological effects, curcumin is characterized by poor water solubility and absorption. In this study, novel polyurethane microspheres containing curcumin (Cur-PUMs) were prepared using carboxymethyl cellulose sodium to improve the bioavailability and prolong the retention time of curcumin. The prepared Cur-PUMs were characterized by Fourier transform infrared spectroscopy, scanning electron microscope, and ultraviolet spectrophotometer. The sustained-release effects of Cur-PUMs were demonstrated using stability tests in vitro and in vivo pharmacokinetic studies following oral administration. We found that the stability of Cur-PUMs was strongly affected by pH variation. Further, compared with free curcumin, Cur-PUMs showed significantly improved maximum concentration and half-life. Yongmei Hu, Qingshan Li, Wei Hong, Guangzhong Xing, Qilong Jiang, and Wenfeng Lv Copyright © 2014 Yongmei Hu et al. All rights reserved. Heat-Activated Persulfate Oxidation of Chlorinated Solvents in Sandy Soil Sun, 03 Aug 2014 07:57:38 +0000 Heat-activated persulfate oxidative treatment of chlorinated organic solvents containing chlorinated ethenes and ethanes in soil was investigated with different persulfate dosages (20 g/L, 40 g/L, and 60 g/L) and different temperatures (30°C, 40°C, and 50°C). Chlorinated organic solvents removal was increased as persulfate concentration increase. The persulfate dosage of 20 g/L with the highest OE (oxidant efficiency) value was economically suitable for chlorinated organic solvents removal. The increasing temperature contributed to the increasing depletion of chlorinated organic solvents. Chlorinated ethenes were more easily removed than chlorinated ethanes. Moreover, the persulfate depletion followed the pseudo-first-order reaction kinetics (, ). Heat-activated persulfate appeared to be an effective oxidant for treatment of chlorinated hydrocarbons. Jialu Liu, Xijun Gong, Shijun Song, Fengjun Zhang, and Cong Lu Copyright © 2014 Jialu Liu et al. All rights reserved. Microstructural and Mössbauer Spectroscopy Studies of Nanoparticles Thu, 24 Jul 2014 09:13:27 +0000 Zinc substituted magnesium ferrite powders have been prepared by a sol-gel autocombustion method. XRD patterns show that the specimens with and 0.7 exhibit single-phase spinel structure, and more content of Zn in specimens is favorable for the synthesis of pure Mg-Zn ferrites. Room temperature Mössbauer spectra of annealed at 800°C display transition from ferrimagnetic behavior to super paramagnetic behavior with increase in zinc concentration. The Mössbauer spectras of Mg0.5Zn0.5Fe2O4 annealed at different temperatures display the magnetic phase change of the ferrite particles. Jinpei Lin, Yun He, Qing Lin, Ruijun Wang, and Henian Chen Copyright © 2014 Jinpei Lin et al. All rights reserved. Interaction of Hyperoside with Human Serum Albumin and Effect of Glucose on the Binding Wed, 23 Jul 2014 10:59:01 +0000 The interaction of hyperoside (Hyp) with human serum albumin (HSA) and effect of glucose on the binding were studied in simulating physiological condition (pH 7.40). The results suggested that Hyp quenched the endogenous fluorescence of HSA via a static quenching process with the distance of 1.95 nm between Hyp and HSA. Hydrophobic forces played a major role in stabilizing the Hyp-HSA complex. Through synchronous fluorescence monitoring of conformation of HSA, we found that the binding to Hyp can change the microenvironment around tryptophan (Trp) residues. Increasing in glucose concentration over a range from 0 to 9 mM decreased the binding ability of HSA to Hyp, implying that increasing in glucose concentration would increase the concentration of free Hyp. Jie Yang, Lingling Qu, Wenyue Yang, Yun Huang, Ning Jiao, Wenhong Zhan, Ding Zhao, and Lijian Cui Copyright © 2014 Jie Yang et al. All rights reserved. Efficient Discrimination of Some Moss Species by Fourier Transform Infrared Spectroscopy and Chemometrics Mon, 14 Jul 2014 13:35:06 +0000 Fourier transform infrared spectroscopy (FTIR) technique was used to classify 16 species from three moss families (Mielichhoferiaceae, Bryaceae, and Mniaceae). The FTIR spectra ranging from 4000 cm−1 to 400 cm−1 of the 16 species were obtained. To group the spectra according to their spectral similarity in a dendrogram, cluster analysis and principal component analysis (PCA) were performed. Cluster analysis combined with PCA was used to give a rough result of classification among the moss samples. However, some species belonging to the same genus exhibited very similar chemical components and similar FTIR spectra. Fourier self-deconvolution (FSD) was used to enhance the differences of the spectra. Discrete wavelet transform (DWT) was used to decompose the FTIR spectra of Mnium laevinerve and M. spinosum. Three scales were selected as the feature extracting space in the DWT domain. Results showed that FTIR spectroscopy combined with DWT was suitable for distinguishing different species of the same genus. Zhen Cao, Yongying Liu, and Jiancheng Zhao Copyright © 2014 Zhen Cao et al. All rights reserved. The Spectroscopic and Conductive Properties of Ru(II) Complexes with Potential Anticancer Properties Mon, 14 Jul 2014 11:21:23 +0000 Different density functional methods (DFT) have been used to optimize and study the chemistry of five potential anticancer complexes in terms of their electronic, conductive, and spectroscopic properties. Many of the computed properties in addition to the IR and QTAIM analysis of the NMR are dipole moment vector (), linear polarizability tensor (), first hyperpolarizability tensors (), polarizability exaltation index (), and chemical hardness () of the complexes. Stable low energy geometries are obtained using basis set with effective core potential (ECP) approximation but, in the computation of atomic or molecular properties, the metal Ru atom is better treated with higher all electron basis set like DGDZVP. The spectroscopic features like the IR of the metal-ligand bonds and the isotropic NMR shielding tensor of the coordinated atoms are significantly influenced by the chemical environment of the participating atoms. The carboxylic and pyrazole units are found to significantly enhance the polarizabilities and hyperpolarizabilities of the complexes while the chloride only improves the polarity of the complexes. Fermi contacts (FC) have the highest effect followed by the PSO among all the four Ramsey terms which defined the total spin-spin coupling constant J (HZ) of these complexes. Adebayo A. Adeniyi and Peter A. Ajibade Copyright © 2014 Adebayo A. Adeniyi and Peter A. Ajibade. All rights reserved. Influence of Zn/Fe Molar Ratio on Optical and Magnetic Properties of ZnO and ZnFe2O4 Nanocrystal as Calcined Products of Layered Double Hydroxides Thu, 10 Jul 2014 09:54:07 +0000 The coprecipitation method has been used to synthesize layered double hydroxide (Zn-Fe-LDH) nanostructure at different Zn2+/Fe3+ molar ratios. The structural properties of samples were studied using powder X-ray diffraction (PXRD). LDH samples were calcined at 600°C to produce mixed oxides (ZnO and ZnFe2O4). The crystallite size of mixed oxide was found in the nanometer scale (18.1 nm for ZnFe2O4 and 43.3 nm for ZnO). The photocatalytic activity of the calcination products was investigated using ultraviolet-visible-near infrared (UV-VIS-NIR) diffuse reflectance spectroscopy. The magnetic properties of calcined LDHs were investigated using a vibrating sample magnetometer (VSM). The calcined samples showed a paramagnetic behavior for all Zn2+/Fe3+ molar ratios. The effect of molar ratio on magnetic susceptibility of the calcined samples was also studied. Abdullah Ahmed Ali Ahmed, Zainal Abidin Talib, Mohd Zobir Hussein, Moayad Husein Flaifel, and Naif Mohammed Al-Hada Copyright © 2014 Abdullah Ahmed Ali Ahmed et al. All rights reserved. Sub-THz Characterisation of Monolayer Graphene Mon, 07 Jul 2014 07:50:19 +0000 We explore the optical and electrical characteristics of monolayer graphene by using pulsed optoelectronic terahertz time-domain spectroscopy in the frequency range of 325–500 GHz based on fast direct measurements of phase and amplitude. We also show that these parameters can, however, be measured with higher resolution using a free space continuous wave measurement technique associated with a vector network analyzer that offers a good dynamic range. All the scattering parameters (both magnitude and phase) are measured simultaneously. The Nicholson-Ross-Weir method is implemented to extract the monolayer graphene parameters at the aforementioned frequency range. Ehsan Dadrasnia, Sujitha Puthukodan, Vinod V. K. Thalakkatukalathil, Horacio Lamela, Guillaume Ducournau, Jean-Francois Lampin, Frédéric Garet, and Jean-Louis Coutaz Copyright © 2014 Ehsan Dadrasnia et al. All rights reserved. Performance of a Novel Hydrophobic Mesoporous Material for High Temperature Catalytic Oxidation of Naphthalene Thu, 03 Jul 2014 10:04:08 +0000 A high surface area, hydrophobic mesoporous material, MFS, has been successfully synthesized by a hydrothermal synthesis method using a perfluorinated surfactant, SURFLON S-386, as the single template. N2 adsorption and TEM were employed to characterize the pore structure and morphology of MFS. Static water adsorption test indicates that the hydrophobicity of MFS is significantly higher than that of MCM-41. XPS and Py-GC/MS analysis confirmed the existence of perfluoroalkyl groups in MFS which led to its high hydrophobicity. MFS was used as a support for CuO in experiments of catalytic combustion of naphthalene, where it showed a significant advantage over MCM-41 and ZSM-5. SEM was helpful in understanding why CuO-MFS performed so well in the catalytic combustion of naphthalene. Experimental results indicated that MFS was a suitable support for catalytic combustion of large molecular organic compounds, especially for some high temperature catalytic reactions when water vapor was present. Guotao Zhao, Zhenxiao Zhao, Junliang Wu, and Daiqi Ye Copyright © 2014 Guotao Zhao et al. All rights reserved. Rapid Discrimination of Chlorpheniramine Maleate and Assessment of Its Surface Content Uniformity in a Pharmaceutical Formulation by NIR-CI Coupled with Statistical Measurement Thu, 26 Jun 2014 13:34:33 +0000 This study demonstrated that near infrared chemical imaging (NIR-CI) was a rapid and nondestructive technique for discrimination of chlorpheniramine maleate (CPM) and assessment of its surface content uniformity (SCU) in a pharmaceutical formulation. The characteristic wavenumber method was used for discriminating CPM distribution on the tablet surface. To assess the surface content uniformity of CPM, binary image and statistical measurement were proposed. Furthermore, high-performance liquid chromatography (HPLC) was used as reference method for accurately determining volume content of CPM in the sample. Moreover, HPLC was performed to assess volume content uniformity (VCU) of CPM in whole region and part region of the tablets. The NIR-CI result showed that the spatial distribution of CPM was heterogeneous on the tablet surface. Through the comparison of content uniformity of CPM determined by NIR-CI and HPLC, respectively, it demonstrated that a high degree of VCU did not imply a high degree of SCU of the samples. These results indicate that HPLC method is not suitable for testing SCU, and this has been verified by NIR-CI. This study proves the feasibility of NIR-CI for rapid discrimination of CPM and assessment of its SCU, which is helpful for the quality control of commercial CPM tablets. Luwei Zhou, Zhisheng Wu, Xinyuan Shi, Manfei Xu, Xiaona Liu, Bing Xu, and Yanjiang Qiao Copyright © 2014 Luwei Zhou et al. All rights reserved. Study on the Gelation of Foamed Gel for Preventing the Spontaneous Combustion of Coal Thu, 26 Jun 2014 06:38:27 +0000 According to the existing deficiencies in fire prevention technology, a new technique named foamed gel is developed to prevent coal mine fire efficiently. Foamed gel, formed by adding the type F3 foam agent, polymer H, and AL into water, introducing nitrogen and stirring physically and mechanically, is a complex multicomponent foam system. The effects of the mass fraction and mixed ratios of polymer H and polymer AL blends on gelation were comprehensively studied. The results show that the optimum performance can be got when the mass fraction of blends was 0.6% and the mixed ratio was 5 : 5. In addition, the interaction between molecules of these polymer blends was also investigated with the help of atomic force microscope. It can be found that the polymers H and AL, through having crosslinking reaction with each other, formed three-dimensional network structures, which can not only increase the nodes of the foamed gel system but also enhance the structures. Leilin Zhang and Botao Qin Copyright © 2014 Leilin Zhang and Botao Qin. All rights reserved. Quasielastic Light Scattering and Structure of Nanodroplets Mixed with Polycaprolactone Mon, 23 Jun 2014 11:16:57 +0000 The interaction of polycaprolactone (PCL) with droplets of a microemulsion is studied with quasielastic light scattering and small angle X-ray scattering At constant droplet size we vary the PCL concentration and there is clear evidence for an increasing attractive interaction of the droplets from structural investigations with small-angle X-ray scattering (SAXS). The collective diffusion coefficient () of the droplets is monitored with quasielastic light scattering (QELS). We mainly focus on the variation of the dynamic behavior as a function of the PCL concentration and length scale (M.W. = 5000 and 10000) in microemulsion. With increasing PCL concentration and length scale the dynamics of the system slow down. A hard sphere model with depletion potential can fit well the SAXS experiment of microemulsion mixed with PCL. The results show with increase of PCL on microemulsion the size of droplets is constant at 83Å but the size ratio of polymer to droplets is changing. Soheil Sharifi Copyright © 2014 Soheil Sharifi. All rights reserved. Analysis of the Oil Content of Rapeseed Using Artificial Neural Networks Based on Near Infrared Spectral Data Mon, 23 Jun 2014 00:00:00 +0000 The oil content of rapeseed is a crucial property in practical applications. In this paper, instead of traditional analytical approaches, an artificial neural network (ANN) method was used to analyze the oil content of 29 rapeseed samples based on near infrared spectral data with different wavelengths. Results show that multilayer feed-forward neural networks with 8 nodes (MLFN-8) are the most suitable and reasonable mathematical model to use, with an RMS error of 0.59. This study indicates that using a nonlinear method is a quick and easy approach to analyze the rapeseed oil’s content based on near infrared spectral data. Dazuo Yang, Hao Li, Chenchen Cao, Fudi Chen, Yibing Zhou, and Zhilong Xiu Copyright © 2014 Dazuo Yang et al. All rights reserved. Infrared Spectroscopic Study on the Modified Mechanism of Aluminum-Impregnated Bone Charcoal Sun, 22 Jun 2014 12:28:50 +0000 Fluoride contamination in drinking water is a prominent and widespread problem in many parts of the world. Excessive ingestion of fluoride through water can lead to the high risk of fluorosis in human body. Bone charcoal, with the principal active component of hydroxyapatite, is a frequently used adsorbent for fluoride removal. Many laboratory experiments suggest that the aluminum-impregnated bone charcoal is an effective adsorbent in defluoridation. However, the mechanisms underlying this modification process are still not well understood, which in turn greatly impedes the further studies on other different modified adsorbents. To address this issue, we used the infrared spectroscopy to examine the bone charcoal and the aluminum-impregnated bone charcoal, respectively. The comparative results show that the −OH peak of infrared spectroscopy has been intensified after modification. This significant change helped speculate the modified mechanism of the aluminum-impregnated bone charcoal. In addition, it is found that the hydroxide ion dissociates from hydroxyapatite in the modification process. Such finding implies that the tetrahydroxoaluminate can be combined with the hydroxyapatite and the aluminum ion can be impregnated onto the bone char surface. Hao Li, Yufan Yang, Shuangjun Yang, Anpu Chen, and Dazuo Yang Copyright © 2014 Hao Li et al. All rights reserved. Spectral Separation for Multispectral Image Reproduction Based on Constrained Optimization Method Sun, 22 Jun 2014 00:00:00 +0000 The constrained optimization method is employed to calculate the colorant values of the multispectral images. Because the spectral separation from the 31-dimensional spectral reflectance to low dimensional colorant values is very complex, an inverse process based on spectral Neugebauer model and constrained optimization method is performed. Firstly, the spectral Neugebauer model is applied to predict the colorants’ spectral reflectance values, and it is modified by using the Yule-Nielsen -value and the effective area coverages. Then, the spectral reflectance root mean square (RRMS) error is established as the objective function for the optimization method, while the colorant values are constrained to 0~1. At last, when the nonlinear constraints and related parameters are set appropriately, the colorant values are accurately calculated for the multispectral images corresponding to the minimum RRMS errors. In the experiment, the colorant errors of the cyan, magenta and yellow inks are all below 2.5% and the average spectral error is below 5%, which indicate that the precision of the spectral separation method in this paper is acceptable. Bangyong Sun, Han Liu, and Shisheng Zhou Copyright © 2014 Bangyong Sun et al. All rights reserved. Online Monitoring of Water-Quality Anomaly in Water Distribution Systems Based on Probabilistic Principal Component Analysis by UV-Vis Absorption Spectroscopy Thu, 19 Jun 2014 07:46:49 +0000 This study proposes a probabilistic principal component analysis- (PPCA-) based method for online monitoring of water-quality contaminant events by UV-Vis (ultraviolet-visible) spectroscopy. The purpose of this method is to achieve fast and sound protection against accidental and intentional contaminate injection into the water distribution system. The method is achieved first by properly imposing a sliding window onto simultaneously updated online monitoring data collected by the automated spectrometer. The PPCA algorithm is then executed to simplify the large amount of spectrum data while maintaining the necessary spectral information to the largest extent. Finally, a monitoring chart extensively employed in fault diagnosis field methods is used here to search for potential anomaly events and to determine whether the current water-quality is normal or abnormal. A small-scale water-pipe distribution network is tested to detect water contamination events. The tests demonstrate that the PPCA-based online monitoring model can achieve satisfactory results under the ROC curve, which denotes a low false alarm rate and high probability of detecting water contamination events. Dibo Hou, Shu Liu, Jian Zhang, Fang Chen, Pingjie Huang, and Guangxin Zhang Copyright © 2014 Dibo Hou et al. All rights reserved. Structural Characterization of Carbon Nanomaterial Film In Situ Synthesized on Various Bulk Metals Thu, 19 Jun 2014 07:34:13 +0000 Carbon nanofiber films were prepared via a simple chemical vapor deposition (CVD) method on various bulk metal substrates including bulk 316 L stainless steel, pure cobalt, and pure nickel treated by surface mechanical attrition treatment (SMAT). The microstructures of the carbon nanomaterial film were studied by SEM, TEM, XRD, and Raman spectroscopy. In this paper, bulk metallic materials treated by SMAT served as substrates as well as catalysts for carbon nanomaterial film formation. The results indicate that the carbon nanofiber films are formed concerning the catalytic effects of the refined metallic particles during CVD on the surface of SMAT-treated bulk metal substrates. However, distinguished morphologies of carbon nanomaterial film are displayed in the case of the diverse bulk metal substrates. J. Y. Xu, R. Yang, Z. Z. Fan, and X. C. Lei Copyright © 2014 J. Y. Xu et al. All rights reserved. Liquid Chromatography-Tandem Mass Spectrometric Assay for Determination of Stavudine in Human Plasma Tue, 17 Jun 2014 09:27:26 +0000 A LC-MS/MS method for determination of stavudine in human plasma was established and validated, and it was applied to the pharmaceutical formulations bioequivalence study. 0.5 mL plasma sample was extracted by liquid-liquid extraction. Stavudine was detected by a LC-MS/MS system. The pharmacokinetic parameters of stavudine in different formulations were calculated by noncompartment model statistics. The method was linear over the concentration ranges 5.00–1000 ng/mL in plasma. The intra- and interassay relative standard deviation (RSD) was <10%. The average accuracies for the assay at three concentrations (5.00, 80.0, and 900 ng/mL) were from 100.2% to 102.5%. Pharmacokinetic parameters of stavudine reference formulation were obtained as follows: was  h, was  g/L, t1/2 was  h, and was  g·h/L, and pharmacokinetic parameters of stavudine test formulation were obtained as follows: was  h, was  g/L, t1/2 was  h, and was () g·h/L. Calculated with , the bioavailability of two formulations was 105.0%. Fengdan Jin Copyright © 2014 Fengdan Jin. All rights reserved. Thickness-Controllable Silica Coating of CdTe QDs by Reverse Microemulsion Method for the Application in the Growth of Rice Sun, 15 Jun 2014 11:38:55 +0000 Herein, we report the synthesis and surface modification of CdTe quantum dots (QDs) and the application in the rice growth. Water-soluble thioglycolic acid (TGA) stabilized CdTe quantum dots were synthesized firstly and then the surface modification was conducted. II–VI semiconductor nanocrystals prefer to be coated with silica as inert materials to improve their chemical properties. The toxicity of QDs reduced after the modification. Silica coated QDs were used in the growth of rice seed and the effect was discussed. In our knowledge it is the first time we report that the silica coated QDs had nice effect on the growth of rice. Aiwu Wang, Yuhong Zheng, and Feng Peng Copyright © 2014 Aiwu Wang et al. All rights reserved. Size Effects: The Relation to the Percentage of Atoms That Participate in the Deformation of ZrCu Metallic Glass Sun, 15 Jun 2014 00:00:00 +0000 Molecular dynamics simulations indicate that with the model diameter gradually decreasing the deformation mode of ZrCu metallic glass evolves from highly localized shear band formation to homogeneous deformation with obvious transition in  nm. Through the statistic of atoms that sustain shear strain larger than 8% in the models with 8% strain along -direction, we found that the main reason for the uniform deformation that occurs in the smallest size model is that there are 61% atoms involved in the deformation, which significantly decrease the strain assigned to individual atoms, avoiding large atomic rearrangement and making those atoms evenly distributed in the model matrix. L. K. Gao, F. L. Zhao, N. Xu, L. Qi, and R. P. Liu Copyright © 2014 L. K. Gao et al. All rights reserved. Observation of Climacteric-Like Behavior of Citrus Leaves Using Fluorescence Spectroscopy Wed, 11 Jun 2014 09:02:05 +0000 Observation of climacteric-like behavior in citrus leaves depends on the detection of ethylene. However, such detection requires a gas chromatographer and complex sample preparation procedures. In this work, fluorescence spectroscopy was investigated as a diagnostic technique for climacteric-like behavior in citrus leaves. Our results indicate that the chlorophyll fluorescence presents a time evolution consistent with the ethylene evolution. Therefore, fluorescence spectroscopy may be used to observe the climacteric-like behavior in citrus leaves. Caio B. Wetterich, Emery C. Lins, José Belasque Jr., and Luis G. Marcassa Copyright © 2014 Caio B. Wetterich et al. All rights reserved. Preparation and Characterization of Binary Organogels via Some Azobenzene Amino Derivatives and Different Fatty Acids: Self-Assembly and Nanostructures Wed, 11 Jun 2014 07:10:48 +0000 In present work the gelation behaviors of binary organogels composed of azobenzene amino derivatives and fatty acids with different alkyl chains in various organic solvents were designed and investigated. Their gelation behaviors in 20 solvents were tested as new binary organic gelators. It showed that the length of alkyl substituent chains and azobenzene segment have played a crucial role in the gelation behavior of all gelator mixtures in various organic solvents. Longer alkyl chains in molecular skeletons in present gelators are favorable for the gelation of organic solvents. Morphological studies revealed that the gelator molecules self-assemble into different aggregates from lamella, wrinkle, to belt with change of solvents. Spectral studies indicated that there existed different H-bond formation and hydrophobic force, depending on different substituent chains in molecular skeletons. The present work may also give new perspectives for designing new binary organogelators and soft materials. Haiying Guo, Tifeng Jiao, Xihai Shen, Qingrui Zhang, Adan Li, and Faming Gao Copyright © 2014 Haiying Guo et al. All rights reserved. Preparation and Characterization of P(AN-VAc-PMMT) Nanocomposites and Nanofibers Mon, 09 Jun 2014 10:57:25 +0000 P(AN-VAc-PMMT) nanocomposites were prepared using in situ emulsion polymerization and further confirmed by FTIR. A polymerizable quaternary ammonium ion monomer was used to modify montmorillonite. XRD testing showed that the quaternary ammonium ion was successfully intercalated into the montmorillonite chip layer. This is the first paper to discuss an investigation of P(AN-VAc-PMMT) nanofiber morphology using SEM. The fibers were prepared through electrospinning. Jun Liu, Yuguo Zhuo, Qingshan Li, Wei Hong, and Guangzhong Xing Copyright © 2014 Jun Liu et al. All rights reserved.