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Three aryl and three naphthylmethylene derivatives containing thiadiazole ring have been synthesized. The structures of target compounds were characterized on the basis of spectral (FT-IR, 1H NMR, and MS). The optical properties were detected using UV-vis absorption spectroscopy and fluorescence spectroscopy. The absorption spectra of 1a, 2a and 3a substituted by naphthylmethylene are primarily characterized by a peak around 284 nm originating from naphthalene, which is different from that of compounds 1b, 2b and 3b. Compared to 1a and 2a (separated by a saturable atomic cluster −CH2−), the maximum absorption wavelength of 1b and 2b takes on obvious red-shifted, which is from thiadiazole and benzene with more large conjugated system. The fluorescence intensity of 2-(4-aminobenzoyl) amide-5-naphthylmethylene-1,3,4-thiadiazole (3a) was significantly higher than that of 5-(4-aminobenzoyl)-1,3,4-thiadiazole (3b) due to the presence of naphthalene.

Asymmetric 2-p-nitrophenyl-5-naphthylmethylene-1,3,4-oxadiazole and 2-p-aminophenyl-5-naphthylmethylene-1,3,4-oxadiazole were synthesized and characterized by IR、1HNMR and MS analysis, and their optical properties were detected using UV-vis absorption spectroscopy and fluorescence spectroscopy. The existence of electron-withdrawing oxadiazole units causes a significant bathochromic shift of the UV absorption maximum. The largest UV-absorption peak of target compounds is in the range of 298-317 nm, and a new emission band at 402 nm is formed. The fluorescence intensity is gradually enhanced, which strengthens the intramolecular charge transfer effect between the electron-withdrawing oxadiazole and electron-donating aniline.

Poaching for massive traditional medicine demands is the single greatest threat of extinction that looms over most wildlife especially the endangered tiger. One way to curb the poaching activity is to have tighter monitoring of the protected area by using camera traps. In this research, an embedded system with human detection features for anti-poaching application is proposed. The system uses a 4 × 4 pixels' thermal sensor to detect any heat presence before an infrared camera is activated to capture video images. The images will be processed with a human detection algorithm based on frame differencing and orientation features. The detected human will then be verified using a Support Vector Machine (SVM) classifier. Once a human is identified, the image and the location of the human can then be sent through a long range data connection to a ranger office to alert the authorities. The system was implemented on a Raspberry Pi 2 board. Experiments have been conducted to evaluate the functionality of the system in non-urban environment during day and night times. The results showed that it can successfully detect human in an average of less than 2s even during night time with complete darkness.

Three novel triphenylamine (TPA) derivatives having perfluorinated cyclopentenyl and benzo[b]thiophene unit are obtained from 4-bromo-N,N-diphenyl-2-methylbenzo[b]thiophen-5-amine. The new compounds are expected to find their use in thin film devices as charge transport materials and host organic light-emitting materials. It is found that the new compounds show relatively strong fluorescence either in solution or in solid state, and are amorphous due to a special conformation which is elucidated by the fine structure of 19F NMR. Molecular structure and properties of these compounds is characterized by 1H NMR, 13C NMR (broadband decoupled), ESI–HRMS, elemental analysis and thermal analysis (DSC). Fluorescent quantum yield in solution is measured using 9,10-diphenylanthrancene (DPA) as standard fluorescent substance.

5-Diarylamino-2-methylbenzo[b]thiophene was a new kind of triphenylamine-based charge-transporting material. For further modification of the compounds, bromination selectivity was studied through experiments and molecular simulation using Gaussian 09 program under B3LYP/6-311G (d, p) aided by Gaussian View 05 and Multiwfn Program. The results showed that bromination of 5-diarylamino-2-methyl-benzo[b]thiophene would occurred at an “abnormal” positions (4- and/or 4′-position) rather than at the “normal” position (3-position), which was different from those benzo[b]thiophene derivatives with simple 5-substitutes reported in literatures. The “abnormal” selectivity resulted from a special electron structure in which there was an “interfinger-like” frontier orbital or a special “non-planar” conjugated model. Electrons would be donated to the o - and p -positions of linked aromatic rings by this manner of electron delocalization, so that TPA unit rather than thiophene ring became the main factor in the selectivity, and reaction active energy at 4-position was lowest. The results were confirmed by the synthesis of three 4-Br and/or 4′-Br derivatives, compound 4 , 5 and 6 . Single crystal X-ray diffraction of compound 6 gave conclusive evidence on the abnormal selectivity.

Eight ionic liquid crystals containing a biphenyl ester-based rigid core modified by a 3-alkyl-imidazolium cation were synthesised and characterised. The length of the alkyl chain varied between n = 4–18 carbon atoms. Their thermotropic phase behaviour was investigated using X-ray diffraction (XRD) measurements, variable temperature small-angle X-ray scattering (SAXS), polarising optical microscopy (POM) and differential scanning calorimetry (DSC). The compounds show rich mesomorphism, such as SmA2 phase (for compound C18) and SmC2 phases (for compounds C12–C16). For the molecules containing long alkyl chains (n ≥ 12), a novel mesophase, the T′ phase, was seen which has a unique ‘sandwich-like layer’ structure. The T′ phase is different from the known T phase and is formed at room temperature. Based on XRD, SAXS, DSC and POM data, models for the formation of the T′ phase are proposed.

The inorganic electrophoretic particles easily sedimentate and are not preferably dispersed in medium because their density is relatively big. Spheric and hollow TiOB2Bparticles were prepared against the core-shell polymer latex particles via a simple wet-chemistry route, using Ti(OBu)B4Bas a precursor. The particles¢ morphology was observed by atom force microscopy (AFM) images, scanning electron microscope (SEM) and transmission electron microscopy (TEM). The products were characterized by X-ray Diffraction (XRD) and TEM. TEM showed spheric and hollow particles with a diameter around 290 nm. The density (in the atmospheric pressure, 20°C) of TiOB2Bwas 2.21 g∙mLP-1P. Results showed that hollow framework could reduce the density of particles. The Zeta potentials were determined by micro-electrophoresis apparatus. TiOB2Bparticles had good electrophoretic property, and the Zeta potential was 5.25 mV.

Hollow TiOX nano-spheres have been successfully prepared using hollow core-shell latex particles as template, which involves the deposition of inorganic coating on the surface of hollow core-shell latex particles and subsequent removal of the latex particles by calcinations in air or ammonia gas. The formation route of hollow core-shell polymer particles is presented as follows: Firstly, poly-methyl methacrylate (PMMA) seed emulsions are prepared as the 'core'. Subsequently, the outer shell poly(styrene-co-methyl methacrylate) (PS-co-MMA) particles wrap on the surface of the core, the microspheres with core-shell have been prepared. Finally, Ti(OBu)4 is used as precursor for the preparation of hollow TiOX nanospheres. Transmission electron microscopy (TEM) and atom force microscopy (AFM) images of seed emulsions show they have the uniform size of about 470 nm. TEM of hollow core-shell polymers particles show they have an average diameter of about 500 nm. X-ray diffraction (XRD) analysis of TiO2 sample calcined presents that the strong absorptions is coordinated with the standard chart of rutile TiO2. TEM of TiO2 and TiO show hollow spheres well-dispersed with the diameter range of 300-400 nm and 350-400 nm, respectively. The density (in the atmospheric pressure, 20 °C) of TiO2 and TiO hollow spheres was 2.49 and 2.37 g∙mL-1, respectively. The Zeta potentials were 6.20 mV and 20.39 mV, respectively. Uniform hollow spheres show low density and good electrophoretic displays. The electrophoretic mobilities of white TiO2 and black TiO hollow spheres in tetrachloroethylene show they are suitable for electronic paper as background and display particles, respectively. It is anticipated that this method would present a potential toward the road of large-scale industrial production of TiOx hollow spheres.

A modified framework, that applies temporal association rule mining to financial time series, is proposed in this paper. The top four components stocks (stock price time series, in USD) of Dow Jones Industrial Average (DJIA) in terms of highest daily volume and DJIA (index time series, expressed in points) are used to form the time-series database (TSDB) from 1994 to 2007. The main goal is to generate profitable trades by uncovering hidden knowledge from the TSDB. This hidden knowledge refers to temporal association rules, which represent the repeated relationships between events of the financial time series with time-parameter constraints: sliding time windows. Following an approach similar to Knowledge Discovery in Databases (KDD), the basic idea is to use frequent events to discover significant rules. Then, we propose the Multi-level Intensive Subset Learning (MIST) algorithm and use it to unveil the finer rules within the subset of the corresponding significant rules. Hypothesis testing is later applied to remove rules that are deemed to occur by chance. After which, multi-period portfolio optimization is done to demonstrate the practicality of using the rules in the real world.

A modified framework, that applies temporal association rule mining to financial time series, is proposed in this paper. The top four components stocks of Dow Jones Industrial Average DJIA in terms of highest daily volume and DJIA index time series, expressed in points are used to form the time-series database TSDB from 1994 to 2007. The main goal is to generate profitable trades by uncovering hidden knowledge from the TSDB. This hidden knowledge refers to temporal association rules, which represent the repeated relationships between events of the financial time series with time-parameter constraints: sliding time windows. Following an approach similar to Knowledge Discovery in Databases KDD, the basic idea is to use frequent events to discover significant rules. Then, we propose the Multi-level Intensive Subset Learning MIST algorithm and use it to unveil the finer rules within the subset of the corresponding significant rules. Hypothesis testing is later applied to remove rules that are deemed to occur by chance.

The synthesis and photochromic properties of novel 2,2-diarylnaphthopyrans were described. Significantly, the nanostructured architecture through two-component self-assembly of a photochromic naphthopyran and an asymmetric biphenyl was determined by X-ray diffraction. The structure motifs of nanocavities were formed by Cl⋯O interactions and Ar–H⋯Cl hydrogen bonds among the photochromic naphthopyran molecules. It was further shown by TEM that the dimensions of cavity structures were up to nanometer level, which provides the potential to capture useful nanoscale entities and control photochromism in organic materials.

Achiral benzoic acid derivatives were cocrystallized with a range of amines, affording binary or ternary cocrystals [(p-nitrobenzoic acid)·(2-aminopyridine)] (1), [(p-nitrobenzoic acid)·(4,4‘-bipyridine)] (2), [(p-nitrobenzoic acid)·(p-methoxyaniline)] (3), [(3,5-dinitrobenzoic acid)·(2,2‘-bipyridine)] (4), [(3,5-dinitrobenzoic acid)·(4, 4‘-bipyridine)] (5), and [(phthalic acid)·(2-aminobenzimidazole)] (6) under specified conditions. All the prepared cocrystals have a common structural feature of the 21 screw axis. It is noteworthy that the cocrystals 1*, 4*, and 6*, achiral benzoic acid derivatives and nitrogen bases, are noncentrosymmetric and chiral cocrystals. Strong N−H···O interactions are involved in the chiral cocrystals, undoubtedly following the best donor/acceptor guidelines. X-ray single-crystal diffraction studies reveal that the stronger N−H···O and O−H···N interactions, as well as weaker C−H···O ones, are all among the driving forces for the construction of the hydrogen-bonding networks in ...

A series of novel heterocycle-containing spirooxazines have been designed and synthesized, and their photochromic properties were investigated under flash photolysis and continuous irradiation in particular regard to the fatigue resistance, the lifetime of the colored merocyanine form in various solutions and polymers. Especially, the characteristics of two UV-sensitive spirooxazines dispersed polymethylmethacrylate thin-films were extensively studied. Detailed studies showed that general significant shifts in the λ max of the absorption spectra of the open forms, interesting fatigue resistances and emission fluorescene properties were observed.

A novel photochromic compound, 3, 3-(2, 4-dimethoxy-phenyl)-3H-naphtho [2, 1-b] pyran (Compound I), was synthesized and the structure was determined by X-ray diffraction and TEM. Introduction of methoxy groups in the 2, 4-position of the phenyl moiety affects the whole arrangement of molecular self-assembly. The structure displays motifs formed by only weak C–H⋯π interactions. The motifs thus generated show cavities, which could serve as hosts for complexation. To our surprise, it was shown that the aperture of the cavity structure is up to nanometer level by TEM, which is rarely seen in organic compound. Moreover, the photochromic properties of the compound I in solid state and polyvinyl butyral film were studied. The results showed compound I exhibited good reversible photochromism.

An effective financial market trading decision is usually dependent on superior forecasting. Forex market as the largest financial market is chosen in this study. The main objective of this paper is to explore the forecasting performance of the proposed multiple-price model which integrates close, low and high price information, by using Artificial Neural Network (ANN). The architecture of the network and the related algorithms are described. The effects due to different choices of preprocessing methods, combinations of input variables and different time intervals of forecasting are examined. By using the best multiple-price model, trading strategies with high and low prices are developed as well. The results have shown that in terms of both absolute values and trends of the prices, forecasting accuracy has improved compared with single price model. This is especially so for low and high prices whose directional accuracies are much higher. The trading performance is also proven to have much better total return than buy & hold strategy, and trading with high price has the best overall performance considering both return and risk.

The asymmetric bi­phenyl title compound, C14H13ClO2, exhibits a significant twist of ca 30° about the central C—C bond.