Removal of hexavalent chromium from aqueous solution by calcined Zn/Al-LDHs.

In this study, Zn/Al-layered double hydroxides (Zn/Al-LDHs) were synthesized by a co-precipitation method and characterized with X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. Then the hexavalent chromium Cr(VI) adsorption experiments on calcined Zn/Al-LDHs were carried out to analyze the effects of pH, temperature, adsorption time, initial Cr(VI) concentration and adsorbent dosage on the removal of Cr(VI) from aqueous solutions. The maximum adsorption capacity for Cr(VI) on calcined Zn/Al-LDHs under optimal conditions was found to be over 120 mg/g. The kinetic and isotherm of Cr(VI) adsorption on calcined Zn/Al-LDHs can be described with the pseudo-second-order kinetic model and Langmuir isotherm, respectively.

Enhanced chemiluminescence of cerium(IV)-Tween 85 system and the analytical application.

The oxidation reaction between cerium(IV) and Tween 85 in sulfuric acid medium produced weak chemiluminescence (CL). In this paper, it was found that citrate could strongly enhance the CL of cerium(IV)-Tween 85-polyphenol system. Based on studies of ultraviolet-visible spectra and CL spectra, the CL enhancement mechanism had been proposed. It was surmised that the light emission was from an excited oxygen molecular pair O2((1)Δg)O2((1)∑g(-)). The maximum emission wavelength was about 478 nm. The effects of 17 amino acids and 29 organic compounds on cerium(IV)-Tween 85-citrate CL were investigated by a flow injection procedure. This study showed the present system had a wide application for the determination of these compounds.

High performance polymeric aluminum silicate sulfate (PASS) flocculant from abandoned molecular sieve.

PASS is an innovative inorganic polymer flocculant (IPF), which possesses the advantages of a polysilicate/aluminum sulfate-based flocculant. Recently, solid wastes rich in Si and Al, such as kaolinite, rice husks, and abandoned molecular sieves (AMS) have been recognized as promising raw materials for the synthesis of flocculants. The present study involved the synthesis of PASS flocculant derived from AMS. The efficacy of the as-prepared PASS was evaluated through the flocculation of wastewater containing ultramarine blue (UB) pigment. The optimal flocculation performance of PASS was observed at a Si/Al molar ratio of 1.62 and a polymerization time of 9 h. Furthermore, we investigated the impact of PASS dosage, stirring/settling time, and pH on the flocculation process while also exploring potential mechanisms. The PASS flocculant prepared in this study exhibited superior performance compared to the commercially available polyaluminum sulfate (PAS). The results demonstrated the viability of preparing PASS flocculants from waste resources.

Topography and biocompatibility of patterned hydrophobic/hydrophilic zein layers.

The topography and biocompatibility of zein layers adsorbed on patterned templates containing hydrophilic and hydrophobic regions were investigated. Nanopatterned templates consisting of hydrophilic lines on a hydrophobic background were drawn by dip-pen nanolithography (DPN) on gold-coated surfaces. 16-Mercaptohexadecanoic acid (COOH(CH(2))(15)SH, MHA) was used as primary ink to generate hydrophilic lines. Unpatterned surfaces were backfilled with 18-octadecanethiol (CH(3)(CH(2))(17)SH, ODT), which generated hydrophobic regions. Zein was allowed to adsorb on patterned surfaces from alcohol-water solutions. The topography of zein deposits was observed by atomic force microscopy (AFM). Height profiles from AFM measurements revealed that zein deposits followed closely the nanopatterned templates. The biocompatibility of zein layers assembled over hydrophilic/hydrophobic micropatterned templates was investigated. Templates containing MHA lines and ODT regions were generated by micro-contact printing (microCP). Mouse fibroblasts seeded on patterned zein layers proliferated on zein deposited over MHA lines, but not on zein over ODT. The experiment indicated that fibroblast cells were able to respond to variations in the underlying surface chemistry, transmitted by the different orientation adopted by zein on the different substrates. This property may be useful in controlling the spatial distribution of cells on patterned protein layers.

Disposable polydimethylsiloxane/silicon hybrid chips for protein detection.

This paper presents disposable protein analysis chips with single- or four-chamber-constructed from poly(dimethylsiloxane) (PDMS) and silicon. The chips are composed of a multilayer stack of PDMS layers that sandwich a silicon microchip. This inner silicon chip features an etched array of micro-cavities hosting polymeric beads. The sample is introduced into the fluid network through the top PDMS layer, where it is directed to the bead chamber. After reaction of the analyte with the probe beads, the signal generated on the beads is captured with a CCD camera, digitally processed, and analyzed. An established bead-based fluorescent assay for C-reactive protein (CRP) was used here to characterize these hybrid chips. The detection limit of the single-chamber protein chip was found to be 1 ng/ml. Additionally, using a back pressure compensation method, the signals from each chamber of the four-chamber chip were found to fall within 10% of each other.

Morphological characteristics of soft tissue profile of Angle's class II division i malocclusion before and after orthodontic treatment / Características morfológicas del perfil de tejido blando de la clase II de la división I de maloclusión de ángulo antes y después del tratamiento de ortodoncia

SUMMARY: By analysing cephalometrics before and after the treatment of Angle's class II division 1 malocclusion, soft tissue profile changes were observed, and to explore whether there was a correlation between the change of posterior occlusal plane (OP-P) and soft tissue profile. The study aimed to provide a theoretical reference in the clinical diagnosis and orthodontic treatment of early permanent dentition of Angle class II division 1 malocclusion patients. We randomly selected 20 cases of orthodontics in Shanxi Medical University orthodontics patients (aged 12-18 years) of the lateral cephalograms, Winceph 8.0 software was used to measure the posterior occlusal plane (OP-P), TUL-EP, TLL-EP, nasolabial angle, upper lip base thickness, upper lip tension, lower lip H line distance, chin soft tissue thickness and Z angle. And SPSS 22.0 software was used to analyze the correlation between OP-P and other measurement indexes. The change of posterior occlusal plane was positively related to the distance from upper lip to the esthetic plane, the distance from lower lip to the esthetic plane, the tension of the upper lip and distance from lower lip to H line, and the change of posterior occlusal plane was negatively related to nasolabial angle and Z angle. The change of posterior occlusal plane had no significant correlation with upper lip base thickness and soft tissue chin thickness. The change of posterior occlusal plane has an important guiding significance for orthodontic treatment,by focusing on the change of the posterior occlusal plane to achieve the purpose of changing the soft tissue profile.

RESUMEN: Se realizó un estudio cefalométrico antes y después del tratamiento de ortodoncia en pacientes portadores de maloclusión clase II división 1 de Angle. Se observaron cambios en el perfil de los tejidos blandos y se exploró si había una correlación entre el cambio del plano oclusal posterior (OP-P) y el perfil de los tejidos blandos. El objetivo de este estudio fue otorgar una referencia teórica en el diagnóstico clínico y el tratamiento de ortodoncia de los pacientes con dentición permanente temprana con maloclusión clase II división 1 de Angle. Seleccionamos al azar 20 casos cefalometrías de pacientes de ortodoncia de la Universidad Médica de Shanxi (entre 12 y18 años). Para ello, se utilizó el software Winceph 8.0 para medir el plano oclusal posterior (OP-P), TUL-EP, TLL-EP, ángulo nasolabial, grosor de la base del labio superior, tensión del labio superior, distancia entre líneas del labio inferior H, grosor del tejido blando del mentón y ángulo Z. Se utilizó el software SPSS 22.0 para analizar la correlación entre OP-P y otros índices. El cambio del plano oclusal posterior tuvo una correlación positiva con la distancia desde el labio superior al plano estético, la distancia desde el labio inferior hasta el plano estético, la tensión del labio superior y distancia del labio inferior a la línea H. El cambio del plano oclusal posterior tuvo una correlación negativa con el ángulo nasolabial y el ángulo Z. El cambio del plano oclusal posterior no tuvo una correlación significativa con el grosor de la base del labio superior y la barbilla de tejido blando. El cambio del plano oclusal posterior tiene un importante significado de orientación para el tratamiento de ortodoncia, de tal manera que al cambiar el plano oclusal posterior se podrá lograr el propósito de cambiar el perfil del tejido blando.

Micro-implanted-anchorage safety: cortical bone thickness in the maxillary posterior region of skeletal class II malocclusion / Seguridad en el micro-implante de anclaje: espesor del hueso cortical en la región posterior del maxilar en maloclusión de clase esquelética tipo II

Cone Beam Computed Tomography (CBCT) measurement of cortical bone thickness and implantation angle in the maxillary posterior region was used to provide reference for the safety of Micro-Implanted-Anchorage (MIA) implantation in skeletal class II malocclusion. Twenty samples of CBCT images were collected from orthodontics patients (ages, 12-40 years) in Shanxi Medical University Stomatological Hospital, the thickness of cortical bone was measured at 45°, 60° and 90° from the alveolar crest, being at 4 mm, 6 mm and 8 mm, respectively. SPSS17.0 statistical software was used to analyze the data, and the one-way ANOVA and LSD method were compared. There was a significant difference in the thickness of the cortical bone obtained by implanting MIA at the same height of different angle (P≤0.05). The greater the inclination angle of the implanted MIA, the thicker the cortical bone. Also, the higher the implant site, the thicker the cortical bone thickness. Finally, the greater the thickness of the cortical bone in the maxillary posterior region of skeletal class II malocclusion, the greater the thickness of the cortical bone. At the same implantation height, implanted MIA with a tilt angle of 45º to 60º, 90º to obtain the best cortical bone thickness.

La medición del grosor del hueso cortical y del ángulo de implantación en la región posterior del maxilar por tomografía computarizada de haz cónico (TCHC) se utilizó para proporcionar una referencia para la implantación y el anclaje seguros de un Micro-Implante de Anclaje (MIA) en la maloclusión de clase esquelética tipo II. Veinte muestras de imágenes de TCHC fueron obtenidas de pacientes de ortodoncia (12-40 años) en el Hospital Estomatológico de la Universidad Médica de Shanxi. Se midió el grosor del hueso cortical a 45°, 60° y 90° de la cresta alveolar, encontrándose a 4 mm, 6 mm y 8 mm, respectivamente. Se utilizó el software estadístico SPSS 17.0 para analizar los datos, y se compararon con los métodos ANOVA y LSD de un factor. Hubo una diferencia significativa en el grosor del hueso cortical obtenido al implantar el MIA a la misma altura en diferentes ángulos (P <0,05). Cuanto mayor es el ángulo de inclinación del MIA implantado, más grueso es el hueso cortical. También, cuanto más alto es el sitio del implante, más grueso es el grosor del hueso cortical. Finalmente, cuanto mayor sea el grosor del hueso cortical en la región posterior del maxilar, en la maloclusión de clase esquelética tipo II, mayor será el grosor del hueso cortical.

[Comparison research on two-stage sequencing batch MBR and one-stage MBR].

Aiming at resolving problems in MBR operation, like low nitrogen and phosphorous removal efficiency, severe membrane fouling and etc, comparison research on two-stage sequencing batch MBR (TSBMBR) and one-stage aerobic MBR has been done in this paper. The results indicated that TSBMBR owned advantages of SBR in removing nitrogen and phosphorous, which could make up the deficiency of traditional one-stage aerobic MBR in nitrogen and phosphorous removal. During steady operation period, effluent average NH4(+) -N, TN and TP concentration is 2.83, 12.20, 0.42 mg/L, which could reach domestic scenic environment use. From membrane fouling control point of view, TSBMBR has lower SMP in supernatant, specific trans-membrane flux deduction rate, membrane fouling resistant than one-stage aerobic MBR. The sedimentation and gel layer resistant of TSBMBR was only 6.5% and 33.12% of one-stage aerobic MBR. Besides high efficiency in removing nitrogen and phosphorous, TSBMBR could effectively reduce sedimentation and gel layer pollution on membrane surface. Comparing with one-stage MBR, TSBMBR could operate with higher trans-membrane flux, lower membrane fouling rate and better pollutants removal effects.