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The feasibility of using the partial nitration (PN) process to treat wastewater containing tetracycline (TC) and Zn(II) was evaluated in this study. The community structure was analyzed using quantitative real-time PCR. The results suggested that the IC50 of TC and Zn(II) on the PN sludge were 235.8 and 41.8 mg L−1, respectively. The PN sludge was insensitive to TC at a relatively high concentration (≤300 mg L−1) during the short-term exposure. Long-term test demonstrated that the PN sludge could tolerate 150 mg L−1 of TC after a domestication period. The PN performance was significantly inhibited when the concentration of Zn(II) reached 5 mg L−1. Real-time PCR revealed that the dynamics of the ammonia-oxidizing bacteria (AOB) were indicative for the operation of the PN process. The analyses also indicated that there was a direct correlation between the size of the indicative population and PN performance.

A new mealybug, Crisicoccus ziziphus sp. nov. (Hemiptera: Coccomorpha: Pseudococcidae), collected on the leaves and twigs of Ziziphus jujuba (Rhamnaceae), is described from China. All the female developmental stages (adult, third-instar, second-instar and first-instar nymphs) are described and illustrated. Keys are provided to separate the female instars and to identify adult females of Crisicoccus species from China.

The micro/nanofibrils of poplar could be prepared by treatment of ultrasonic. The properties of micro/nanofibrils were characterized by using scanning electron microscopy (SEM) and X-ray diffractometer (XRD). The results indicated that poplar micro/nanofibril was the same as raw fiber in chemical compositions and crystal structure. The crystallinity of micro/nanofibrils was 84.99 percent, increased by 20 percent compared to original fiber after ultrasonic crushing. The micro/nanofibril diameter was from 50 nm to 1 μm.The internal bond strength (IB) of wheat-straw fiberboard could be significantly improved by adding poplar micro/nanofibril suspension to the urea formaldehyde resin adhesive(UF),when the adding amount of poplar micro/nanofibril suspension was 15wt percent, the IB of wheat-straw fiberboard was up to 0.86 MPa.

According to two parameters combination of the material thickness and air-gap depth, from the angle of pure optimization, this paper obtained the optimal parameters of single cavity and double cavity structure by using the simulated annealing algorithm for single cavity and double cavity of aluminum foam sound absorption structure of systematically optimization design at 100-4000HZ frequency band. Finally, studying effect of increasing the number of cavity on aluminum foam sound absorption properties.

The anode material BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3− δ (BZCYYb) for solid oxide fuel cells (SOFCs) is prepared by solid state reaction method and its chemical compatibility with Y 2 O 3 stabilized ZrO 2 (YSZ) is evaluated. The electrochemical performance of the pure and Pd- and Cu 0.5 Pd 0.5 -impreganated BZCYYb electrodes is characterized in the temperature range between 650 and 750 °C by AC impedance spectroscopy in H 2 and/or CH 4 atmospheres, respectively, under the condition of open circuit. It is confirmed that the BZCYYb is chemically compatible with the YSZ at temperatures below 1000 °C. The polarization resistance of the BZCYYb anode in H 2 is decreased from 2.08 to 0.51 Ω cm 2 as the measuring temperature increases from 650 to 750 °C with an activation energy of 117 kJ mol −1 . With Pd- or Cu 0.5 Pd 0.5 -impregnation, the polarization resistance of the BZCYYb electrode in H 2 is reduced significantly to approximately 0.40 Ω cm 2 at 650 °C and 0.12 Ω cm 2 at 750 °C. With dry CH 4 as the fuel, the polarization resistance of the Pd- and Cu 0.5 Pd 0.5 -impregnated BZCYYb anodes is obviously increased below 1.00 Ω cm 2 at 650 °C and 0.22 Ω cm 2 at 750 °C. Both Pd and Cu 0.5 Pd 0.5 impregnations are equivalently effective in enhancing the electrochemical performance of the BZCYYb anode.

Building space cooling load affected by lots of factors,was transient, multi-dimensional and highly interactive. A model of online least squares support vector machine (LS-SVM) was established to forecast the space cooling load of building, and correlation analysis was used to find out the main influencing factors, such as, dry-bulb temperature, solar irradiance, and so on. As an example, the hourly space cooling load of an office building in shanghai was investigated. The hourly space cooling load was firstly calculated by the simulation software of DEST, and then, an online LS-SVM model was presented to forecast the load. The simulation results showed that the online LS-SVM model was effective for space cooling load prediction.

The transmission spectrum of the coated phase-shifted long-period fiber gratings (LPFGs) with single and multiple phase shifts is analyzed by the coupled-mode theory and the transfer matrix method, and the influences of the film parameters on the spectral characteristics are also studied. It is shown that these parameters will affect the LPFG filtering characteristics. The loss peak of transmission spectrum decreases with the increase of film thickness, and the peak position shifts with the film refractive index. Compared with the non-coated phase-shifted LPFG, the coated one has the similar desirable filtering characteristics, and it has a flexible ability to adjust the transmission properties.

The dynamic compressive behavior of Al2O3 (10% vol.) / TiB2 ceramic composite had been tested by using a split Hopkinson pressure bar in this paper. The results show that the main failure modes of the ceramic composite include crushed failure and split fracture along the loading direction. The former is the typical compressive failure of brittle materials. The later is tensile failure along the flaws produced during the composite manufacturing. The numerical simulation was also used to study the effect of the diameter/length ratio of the samples on the experimental results. The effect of the deformation in the bars’ ends, which contacted with the samples, was also studied in the numerical models.

To explore the combined effects of recombinant human platelet-derived growth factor-BB(rhPDGF-BB)and recombinant human transforming growth factor-β1 (rhTGF-β1) on protein expression of FAK in osteolasts of the pressure side of orthodontic tooth in rats.One hundred and sixty male Sprague-Dawley rats were randomly divided into 2 groups: experimental group(A) and control group(B). Each group was subdivided equally into 5 subgroups. Orthodontic tooth movement model was established. The experimental group received injection of 0.1 mL solution, containing 10 ng rhPDGF-BB and 5 ng rhTGF-β1 every other day from day 1. Rats in each subgroup were sacrificed at each of five time points(1, 4, 7, 10 and 14 days) after appliance placement. The distances of the teeth movement were measured using stereomicroscope, and the changes of the amount of osteoclasts were detected by using tartrate resistant acid phosphatase histochemistry (TRAP). The protein expressions of FAK were assayed by immunohistochemical technique. SPSS17.0 software package was used for statistics analysis.Teeth in group A moved more rapidly than group B, and there were significant differences between 2 groups (P0.05) except subgroup A1 and B1(P0.05). The number of osteoclasts in group A was significantly higher than in group B. Except at 14 days, significant differences existed in between other time points (P0.05). The protein expression of FAK in group A was significantly higher than in group B at any time points.The combined effects of rhPDGF-BB and rhTGF-β1 up-regulate the protein expression of FAK within osteoclast in the pressure side, further promoted osteoclast differentiation, proliferation and bone resorption, thus accelerate the rate of orthodontic tooth movement.

To investigate the effect of salvia miltiorhiza on the expression of TGF-β1 within periodontal tissues during orthodontic tooth movement in rat.One hundred and ninety-two male Sprague-Dawley rats were randomly divided into 4 groups (group A, B, C and D). Group A and B were used as orthodontic tooth movement model based on afterburner time. Group A, C and B, D were injected salvia miltiorhiza and NS under the buccal mucosa of left maxillary first molar every other day. Animals in each group were sacrificed at 6 time points (day 1,3,5,7,10 and 14) after appliance placement for collection of specimens. The distance of the tooth movement was measured by stereomicroscope, periodontal tissue was investigated by H-E staining and the protein expression of TGF-β1 was examined by immunohistochemical techniques. SPSS17.0 software package was used for statistical analysis.Except for the first day, the protein expression of TGF-β1 in group A was highest and there was significant up-regulation on day 3, with a peak on day 5. Compared with group B, the average optical density of TGF-β1 in group A was 0.5181±0.0037 on day 3, 0.5857±0.00235 on day 5 and 0.4363±0.0021 on day 7, both with significant differences (P0.01). Compared with group C and group D, significant differences were formed at each time point in group A (P0.05).Salvia injection may improve periodontal tissue microcirculation,thus promote the expression of TGF-β1 protein,which may be one of the mechanisms to accelerate orthodontic tooth movement. Supported by Research Fund of Science and Technology of Honghuagang District, Zunyi City[(2010)11].

The dynamic behaviour of ceramic particle reinforced metal matrix composites (MMCs) is a key to its application. In this paper, the computational micro-mechanics method (CMM) is used to simulate SHPB experiment of MMCs. The numerical SHPB’s specimen of MMCs is firstly generated by CMM. Then, for verifying the correction of numerical experiment, the Al2O3/6061- T6Al composite is used to carry out numerical experiment, and the Johnson-Holmquist (JH-2) damage model is used to describe the ceramic mechanics behaviour, and a comparison between this numerical method and Unit Cell analytical model is carried out. Lastly, the dynamic behaviour of T6061Al/Al2O3 is investigated by this method.

Dynamic response and fracture of high strength boride/alumina ceramic composite were investigated by split Hopkinson pressure bar (SHPB) experiment in this paper. The compressive stress–strain curves and dynamic compression strength of the composites were tested. The surface’s microstructure of fractured composites were examined by using scanning electron microscope (SEM) to investigate the fracture mechanism. The results show that boride/alumina has high dynamic compressive strength and high Young’s modulus. The main fracture mode of the material is the fracture of the ceramic grains. The micro-voids and flaws, generated during the sintering and manufacturing of material and mechanical process of specimen, decrease the strength of the material because they provide the source of crack expansion when the material undergoes the dynamic loadings.

In this paper, the effect of imperfect inner interface on the stress fields in the coated inclusion composite is investigated, the spring-layer of vanishing thickness model is introduced to simulate the imperfect interface, assuming that across the interface between the inclusion and the coating the interfacial traction is continuous while displacement discontinuities are permitted through interfacial traction-displacement jump relations. Numerical examples corresponding to the composites containing single coated spherical and fibrous inclusion, respectively, under shear loading at infinity, are calculated, which indicate that the imperfect inner interfaces have significant effect on stress fields of the composites.

Conducting infrared thermographic nondestructive testing (NDT) by the internal heat generated by Joule effect of components is a new heating approach for flaw detection. Due to the combination of electric field and thermal field, the irregular geometric boundary and the complicated internal heat source distribution, the theoretical solution of transient temperature field is very difficult. Nowadays numerical solution by FEM and FDM is mainly applied. By adopting certain assumptions, this paper presents a method to obtain the approximate temperature field by using Green’s function, and gives the solution of a two-dimensional rectangular field including a circular flaw. By contrast, the result tallies with the FEM results well.

The size of the femoral head and acetabular anteversion are crucial for stability in total hip replacements. This study examined the effects of head diameter and acetabular anteversion on the posterior instability after total hip replacement in an in vivo setting. The acetabular shell was inserted at 0-20° of anteversion at five degree intervals. By using different head sizes (28 mm, 32 mm, 36 mm), the degrees of dislocation were recorded by computer navigation. The 36-mm group consistently showed better stability compared with the 32- and 28-mm groups, regardless of the degree of cup anteversion. Within each group of head size, the hip was significantly more stable when the cup anteversion increased from 0° to 10°. The difference became insignificant when it increased from 15° to 20°. © Springer-Verlag 2010., link_to_OA_fulltext

To evaluate the performance of tumor markers (TM) measurements in clinical laboratories by external quality assessment (EQA) and investigate the comparability of assays for TM.Ten quality control sera specimens were distributed to 586 laboratories by global Express Mail Services (EMS) in March 2008 and tested twice with 5 specimens each time. Analytes were total prostate specific antigen (PSA), free PSA, carcinoembryonic antigen (CEA), alpha fetoprotein (AFP), human chorionic gonadotrophin (HCG), beta-HCG, carbohydrate antigen 19-9 (CA19-9), cancer antigen 15-3 (CA 15-3), cancer antigen 125 (CA125), beta-2-microglobulin and ferritin. The collected data were divided into peer groups according to analyzers or methods and the median of peer group was adopted as the target value (TV) separately after outlier removal. Two standard deviations of the median were set as the limit of difference.The first TM EQA results of 2008 showed that the pass percentage of all participating laboratories ranged from 87.3% (CA125) to 95.5% (beta-2-microglobulin). And the second batch ranged from 83.5% (HCG) to 94.0% (beta-2-microglobulin). The coefficient variances (CVs) of intra-group values determined by automatic analyzers were lesser than 15% for each test of every specimen. The CVs of radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA) were over 20% and 50% respectively. The inter-group medians of 9 tests showed CVs20% with HCG 13.4% and ferritin 15.7%. The CV of paired medians of some automatic analyzers was small and showed no statistical significance (all Z1.890, all P0.05).The analytical performance of automatic analyzers is superior to RIA and ELISA. There is an excellent comparability within automatic analyzers for TM measurements and a lack of comparability within RIA and ELISA. Noncomparability is found in over 80% of TM assays.