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Using 325 mesh flake graphite as raw material, graphite oxide (GO) was synthesized by improved Hummers method. Nitrogen-doped reduced graphene oxide (N-rGO) carrier was prepared by hydrothermal method using urea as nitrogen source, and then supported Ni/N-rGO catalyst was prepared by impregnation method. The prepared catalysts were characterized and analyzed by N2 adsorption-desorption, XRD, SEM, H2-TPR and other methods. The hydrogenation performance of Ni catalysts supported by N-rGO, reduced graphene oxide (rGO) and activated carbon (AC) were compared under the reaction conditions of 150°C, 0.4 MPa and 2.0 h with selective hydrogenation of phenol to cyclohexanone as probe reaction. The results show that the N-rGO support not only has a large specific surface area and suitable pore structure, but also has good synergistic effect with nickel metal, and the Ni/N-rGO catalyst thus shows excellent catalytic activity and selectivity.

Harmonic cavities (HCs) are widely used in electron storage rings, mainly to increase the Touschek lifetime by lengthening bunches. HCs have become critical components of almost all fourth-generation synchrotron light sources. In addition to the benefits of increasing the Touschek lifetime, they also affect the collective beam instabilities in electron storage rings. However, the influence of HC settings on collective beam instabilities is still not well understood. HCs are typically designed to operate under so-called ideal lengthening conditions, which do not necessarily optimize the suppression of collective beam instabilities. We therefore extended earlier studies of collective beam instabilities to consider more general HC settings. We present preliminary studies and analyses of the influences of different HC settings on microwave and transverse mode-coupling instabilities.

Solar-blind deep ultraviolet photodetectors (DUVPDs) based on conventional inorganic ultrawide bandgap semiconductors (UWBS) have shown promising application in various civil and military fields and yet they can hardly be used in wearable optoelectronic devices and systems for lack of mechanical flexibility. In this study, we report a non-UWBS solar-blind DUVPD by designing ultrathin polymer nanofibrils with a virtual ultrawide bandgap, which was obtained by grafting P3HT with PHA via a polymerization process. Optoelectronic analysis reveals that the P3HT-b-PHA nanofibrils are sensitive to DUV light with a wavelength of 254 nm but are virtually blind to both 365 nm and other visible light illuminations. The responsivity is 120 A/W with an external quantum efficiency of up to 49700%, implying a large photoconductive gain in the photoresponse process. The observed solar-blind DUV photoresponse is associated with the resonant mode due to the leakage mode of the ultrathin polymer nanofibrils. Moreover, a flexible image sensor composed of 10 × 10 pixels can also be fabricated to illustrate their capability for image sensing application. These results signify that the present ultrathin P3HT-b-PHA nanofibrils are promising building blocks for assembly of low-cost, flexible, and high-performance solar-blind DUVPDs.

Details of the High Energy Photon Source (HEPS), a 6 GeV green-field diffraction-limited storage ring light source to be built in China, are presented., The High Energy Photon Source (HEPS), a 6 GeV green-field diffraction-limited storage ring light source, will be built in Beijing, China. The HEPS design has been evolving for about ten years, and is now mostly finished and ready for construction. The storage ring is based on a modified hybrid seven-bend achromat (7BA) design, where bending magnets with reverse bending angles and longitudinal gradients are adopted to reach an ultralow natural emittance of 34.2 pm with a circumference of 1360.4 m. The central slice of the dipole in the middle of the modified hybrid 7BA, with flexible magnetic field, is used as the source of the bending-magnet beamline. Moreover, alternating high- and low-beta sections are specially designed to generate and deliver X-ray synchrotron radiation with high brightness of 5 × 1022 photons s−1 mm−2 mrad−2 (0.1% bandwidth)−1. Here, the HEPS storage ring design and solutions to the challenges inherent in this ultralow-emittance design are presented.

Image watermarking focuses on hiding secret data into the cover image imperceptibly to protect the copyright of the original image. In this paper, we propose a new framework of robust digital watermarking for color images using combined embedding techniques of Discrete Fourier Transform (DFT) and Dual Tree Complex Wavelet Transform (DTCWT). The cover image is first divided into Y, U and V channels. The Y channel is then transformed by DFT and partitioned into the ring shapes. With an embedding key, we generate pseudo-random patterns to represent the watermark. These patterns are also transformed and partitioned. The watermark represented by the selection of patterns is then embedded into the rings of the DFT coefficients. We further embed a rectification watermark into the U channel, in which DTCWT is applied to achieve a capability of geometric distortion resilience. On the recipient's side, the detection and extraction of watermark can be successfully done. Compared with previous schemes, the proposed method is better on preserving the image quality. Meanwhile, the robustness against typical attacks is also stronger.

Background: Vitamin A, D and E are very essential to normal growth, development and health of children. Deficiencies are being global problem. The objective of this study is to find out the status of serum vitamin A, D, E level in Children below 14 years in Jiamusi city area (latitude 46?48?N longitude130?19?E) of Heilongjiang province in northeast of China. Methods: Children from birth to 14 years of age who came for normal health check up in First affiliated hospital of Jiamusi University were used to collect blood samples for vitamin A, D, E. Vitamin A and E were measured by High Performance Liquid Chromatography (HPLC) and vitamin D was measured by liquid chromatography-tandem mass spectrometry from sigma company (USA). Results: A total of 3365 children were participated in a year time. These samples were categorized according to age, gender and season groups. The mean levels of serum vitamin A, vitamin D and vitamin E was 0.06mg/L, 24.24ng/ml and 8.56mg/L respectively. There was vitamin A deficiency (VAD) (n=1658, 57.6%), more in 6-14 year age group (n=708, 24.6%) and more in summer season (n=552, 19.2%). Similarly vitamin D deficiency (VDD) (n=1203, 36.9%) more in 6-14 years age group (n=756, 23.2%) and in winter season (n=453, 13.9%) was found. There was significant differences on gender, age group and season for analysis of VAD, p

In order to study how a pulsed magnetic field emission coil produces a stronger magnetic field under the same excitation source, this paper makes a detailed analysis of A method, at the same time, the Ansoft Maxwell finite element simulation software is used to simulate irregular circular and triangular pulsed magnetic field emission coil. We can know from the results of analysis and simulation that the magnetic field intensity of a circular coil is stronger than that of a triangular coil when the radius of a circular coil is equal to the bottom edge of a equilateral triangle coil, that the inclination of the side of the coil can change the direction of the magnetic lines of flux, and the intensity of the magnetic field is strengthened. Several methods of optimizing the coil design in this paper can provide some guidance for the optimization design of the pulsed magnetic field coil.

Underwater target radiated-noise of time domain is significant important in underwater defense and security. Its simulation model based on propeller influencing is considered in this paper. Linear difference equation representing relationship between underwater target radiated-noise of time domain and propeller induced noise is fitted from the data. Dynamical programming is employed to investigate the control of the target radiated-noise. Experimental results show the efficiency of our model and the control methods.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/Apo2L) plays an important role in many biological processes including immune response and cell apoptosis. Here, we identified a soluble TRAIL homolog in a mussel species, Hyriopsis cumingii (designated Hc-sTRAIL), which shows significant structural and functional similarities to mammalian sTRAIL. Real-time PCR analysis shows that mussel TRAIL is ubiquitously expressed in various tissues and involved in the immune response of mussel. Study on its apoptotic effect indicates that Hc-sTRAIL can induce significant apoptosis in NCI-H446 cells and involved the caspase 3 pathway. This study provides new insight into the physiological function of Hc-sTRAIL.

OBJECTIVE: To investigate the influence of silencing PAX2 gene in vivo on epithelial-mesenchymal transition (EMT) of renal tubular cells in rats with renal interstitial fibrosis. METHODS: A total of 64 Wistar rats were anaesthetized, and unilateral ureteral obstruction (UUO) was performed to establish a rat model of renal interstitial fibrosis. The 64 rats were randomly divided into negative control and PAX2 gene silencing groups (n=32 each). The rats in the control group were transfected with 200 μL NC-siRNA-in vivo jetPEI(TM) solution. Those in the PAX2 gene silencing group were transfected with 200 μL PAX2-siRNA-in vivo jetPEI(TM) solution. Each group was further divided into 4 subgroups based on the post-transfection time (3, 5, 7 and 14 days after transfection), with 8 rats in each subgroup. Renal tissue samples were harvested in each group. Real-time PCR and Western blot were used to measure the mRNA and protein expression of PAX2 in the renal cortex, as well as the mRNA and protein expression of E-cadherin and α-SMA. RESULTS: Compared with the control group, the PAX2 gene silencing group showed significantly lower mRNA and protein expression of PAX2 (P < 0.05). In the two groups, the mRNA and protein expression levels of E-cadherin were gradually reduced over the time of obstruction, while those of α-SMA gradually increased. At 14 days after transfection, the PAX2 gene silencing group had significantly higher mRNA and protein expression of E-cadherin but lower mRNA and protein expression of α-SMA compared with the control group (P < 0.05). CONCLUSIONS: PAX2 gene silencing can significantly inhibit the process of EMT of renal tubular cells in rats with advanced fibrosis, suggesting that PAX2 gene silencing may have a therapeutic effect on renal interstitial fibrosis.

A multiplex LAMP (mLAMP) assay was developed for the simultaneous detection of two penaeid shrimp viruses, namely, white spot syndrome virus (WSSV) and infectious hypodermal and hematopoietic necrosis virus (IHHNV), which are the major viral pathogens of penaeid shrimp worldwide. Two sets of the LAMP primers were designed for VP28 gene of WSSV and non-structural protein 1 (NS1) gene of IHHNV, in which a restriction enzyme cleavage site was inserted into two pairs of species-specific primers, to construct the mLAMP assay by combining these two sets totaling eight primers. The mLAMP method was distinguishable between WSSV and IHHNV due to the subsequent restriction enzyme analysis. The sensitivities of the mLAMP method were 102 and 103 times higher on the detection limits for WSSV and IHHNV, respectively, than those of the nested-PCR (nPCR) and classical PCR methods. No positive results were displayed when nucleic acids from other shrimp pathogen DNAs were used as mLAMP templates. Uracil-N-glycosylase (UNG) was used to prevent carry-over contamination of mLAMP products. In addition to its high specificity and sensitivity, the developed multiplex LAMP assay offers an efficient, convenient and rapid tool for screening penaeid shrimp viruses since both WSSV and IHHNV can be diagnosed in a single reaction, and will be useful for the control of these viruses in shrimp.

The densities and viscosities of p-aminophenol in sulfuric acid + water have been determined experimentally at temperatures from (293.15 to 343.15) K. The apparent molar volumes of p-aminophenol were calculated from experimental measurements. Results were fit to obtain the adjustable parameters and standard deviations between the measured and fitted values.

The densities and viscosities of (3-picoline + water) binary mixture have been determined experimentally at temperatures from T = (293.15 to 343.15) K, and the entire mole fraction range of mixture. The excess molar volume, the deviations in viscosity, the excess free energies of activation and the apparent molar volume were calculated from experimental measurements. Results were fitted to obtain the adjustable parameters and standard deviations between the measured and fitted values, respectively. The results were also briefly discussed.

The silkworm Bombyx mori possesses a 30K protein family of 3x10(4) Da, the biological functions of which have not been fully identified. The relationship between the 30K protein family and the embryonic development of temperature sensitive sex-linked mutant strain of silkworm was investigated by two dimensional polyacrylamide gel electrophoresis (2D-PAGE) and Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The results show that protein spots 1-5 of the 30K protein family, mainly existing in normal strain, are possibly related to embryonic development. The early consumption of a 30K protein named 6G1-30K-1 and the accumulation of 30K proteins named 6G1-30K-3 and 6G1-30K-4 are likely caused by the destruction of physiological balance in normal embryonic development, which may lead to lower hatchability of the temperature sensitive strain. The results suggest that reasonable metabolism of 30K proteins is a prerequisite for the embryo's normal development.

The densities and viscosities of niacin + 3-picoline + sulfuric acid + water mixtures have been determined experimentally at temperatures from 293.15 K to 343.15 K. The apparent molar volumes of niacin were calculated from experimental measurements. Results were fit to obtain the adjustable parameters and standard deviations between the measured and fitted values.

The densities and viscosities of niacin + 3-picoline + water mixtures have been determined experimentally at temperatures from 293.15 K to 343.15 K. The apparent molar volumes were calculated from experimental measurements. Results were fit to obtain the adjustable parameters and standard deviations between the measured and fit values.

The low elastic modulus and the ability to withstand high strain without failure make the conducting polymer attractive for a wide range of acoustic applications based on high-strain electroactive polymers. In this article, we examine the electric and electromechanical performance of all-polymer electromechanical systems, fabricated by painting conductive polyaniline (PANI) doped with camphor sulfonic acid (HCSA) on both sides of electrostrictive Poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) copolymer films, and compare them with those from the same copolymers with gold electrodes. The all-polymer composite films are flexible, with strong coherent interfaces between the electrostrictive polymer layer and the conductive polymer layer. The electric performance such as dielectric properties and polarization hysteresis loops from P(VDF-TrFE)/PANI film is nearly identical to those of P(VDF-TrFE)/gold films in a wide temperature (from -50 to 120°C), and frequency range (from 1 Hz to 1 MHz). The all-polymer systems also show a similar or even larger electric field induced strain response than that of films with electrodes under identical measurement conditions. The results demonstrate that the polyaniline/HCSA is good candidate material as the electrodes for electroactive polymers.

The influence of high-energy electron irradiation on the conduction behavior at high current density of polyaniline (PANI) films doped with HCl and camphor sulfonic acid (HCSA), respectively, is reported. It is found that there exists an ohmic region under certain current density for both non-irradiated and irradiated samples. No significant change of the conductivity and maximum current density are observed if the sample is irradiated at room temperature and low dosage. The conductivity and maximum current density decrease with dosage if the samples are irradiated at high temperature. However, after redoping with 1 M HCl, the conductivity of these films can be recovered, while the maximum current density remains at a lower level. The DSC thermograms show that the crosslinking density of PANI–HCl film increases due to the high-energy electron irradiation.

The conduction behavior at high current density at room temperature and above of polyaniline (PANI) films doped with HCl and camphor sulfonic acid (HCSA), respectively, is reported. It is found that the current density deviates strongly from the linear relation with the electric field in high current density region, and a saturation of the current density is observed. The maximum current density Jm seems to be proportional to the conductivity of the sample and hence, for PANI doped with HCl, Jm is about 200 A/cm2, whereas for HCSA doped samples, Jm can reach more than 1,200 A/cm2. The saturation of current density is interpreted as being caused by space charge accumulation at the insulating barrier regions and a dedoping effect in the conduction domains due to the detraping of the ions under high fields. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 2845–2850, 1999

Ion conducting polyurethane electrolyte with redox active ferrocene groups which are fixed to the polymer backbone by covalent bonds was prepared. It has been found that the resulting polyurethane electrolyte has high conductivity even at lower temperature. And the temperature dependence of conductivity follows well the Arrhenius equation. Solid state electrochemical property was measured by cyclic voltammetric method with microdisk electrodes at different temperature. The results indicated that the polyurethane electrolyte has good redox stability, as well as reiteration, and show electrochemical activity in the solid state.

Using a laser monitoring observation technique, the solubilities of p-aminophenol in sulfuric acid + water have been determined experimentally from 286.15 K to 362.80 K. The experimental data were correlated with the modified Apelblat equation. The calculated results showed good agreement with the experimental data.

MFI-type metallosilicates incorporating various transition metal elements were synthesized by the rapid crystallization method. Compared with H-ZSM-5, these metallosilicates possess fewer acid sites and weaker acidic strength. In the methylation of toluene with methanol, protonated metallosilicates exhibited lower conversion of toluene, higher para-selectivity and higher yield of paraxylene than H-ZSM-5. Distributions of trimethylbenzene and tetramethylbenzene isomers produced in toluene methylation indicate that the effective pore size (openings and/or channels) of metallosilicates may be smaller than that of ZSM-5, which is more advantageous for formation of the smallest isomers in trimethylbenzenes and tetramethylbenzenes. The relation between the paraselectivity in toluene methylation and the isomerization activity in para-xylene conversion suggests that the para-selectivity could occur exclusively, when isomerization of para-xylene to other isomers could be completely prevented. Therefore, the improvement in para-selectivity on MFI-type metallosilicates should be attributed to both the reduction in effective pore size and the decrease of strong acid sites, on which produced para-xylene would be isomerized to ortho- and meta-xylenes.

A series of lithium and sodium salts of sulfonated polyethylene oxide (PEO) polyurethane ionomers in different levels of ionization were prepared. It has been found that this material is a new type of ionic conductive polymer, characterized by a single-ion transport mechanism and good mechanical properties. The ionization level significantly influences the ionic conductivity of the samples. When the mole ratio of the metal ion and ether oxygen atom is about 0.05, the ionomers exhibit maximum cationic conductivity. An optimal cationic conductivity of 1.0 × 10−5 S/cm is obtained at about 70°C without any addition of organic plasticizer. The conductivity increases apparently when propylene carbonate and low MW PEO are added to the polyurethane ionomer. © 1995 John Wiley & Sons, Inc.

Loop-mediated isothermal amplification (LAMP) assay is a novel method of gene amplification with high specificity, sensitivity and rapidity, which can be applied for disease diagnosis in shrimp aquaculture. The method is performed under isothermal conditions with a set of four specially designed primers that recognize six distinct sequences of the target. In the present study, according to the conservative regions of non-structural protein gene NS1, a set of four specific primers were designed, and a rapid detection of IHHNV was established by LAMP assay. The parameters of reaction time and temperature were optimized, and its specificity and sensitivity were assessed. The reactions were carried out at 60 degrees C, 62 degrees C, 63 degrees C, 64 degrees C, 65 degrees C, 66 degrees C, 67 degrees C, 68 degrees C for different time (0 min; 15 min; 30 min; 45 min; 60 min; 75 min). A plasmid pMDIHHNV carrying target sequence of LAMP detection was constructed. Ten-fold serially diluted pMDIHHNV (10(7)-10(0)copies/microL) was used as template for LAMP assay to investigate the detection limit. To determine the specificity, LAMP assays were carried out with DNA templates from other pathogens (White spot syndrome virus; WSSV, Taura Syndrome Virus; TSV, Aeromonas. hydrophila, V. alginolyticus, Vibrio. parahaemolytious, Escherichia. coli). The results showed the optimized LAMP assay for the rapid detection of IHHNV was performed at 65 degrees C for 60 min. The LAMP assay had an unequivocal detection limit of 100 copies/microL, and it was 1,000 times lower than that of PCR. The nucleic acids of other pathogens were not amplified by this LAMP system with the specific primers, which showed a good specificity. The resulting amplicons were detected using visual observation after the addition of SYBR Green I and gel electrophoresis. We investigated the efficacy of UNG (uracil-N-glycosylase) and dUTP in avoiding carry-over contamination in the LAMP assay procedure and explored its effect on the amplification efficiency. Products of LAMP with dUTP adding could be lysed by UNG to avoid LAMP products carry-over contamination effectively. The LAMP assay could be finished within an hour, requiring only a regular laboratory water bath or heat block for reaction and the result could easily be detected using visual observation. Clinically suspected IHHNV-infected shrimp samples were detected by both LAMP and PCR assay, and the result indicated that IHHNV was detected rapidly by LAMP instead of by PCR.

The silkworm Bombyx mori possesses a 30K protein family of 3x10(4) Da, the biological functions of which have not been fully identified. The relationship between the 30K protein family and the embryonic development of temperature sensitive sex-linked mutant strain of silkworm was investigated by two dimensional polyacrylamide gel electrophoresis (2D-PAGE) and Matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). The results show that protein spots 1-5 of the 30K protein family, mainly existing in normal strain, are possibly related to embryonic development. The early consumption of a 30K protein named 6G1-30K-1 and the accumulation of 30K proteins named 6G1-30K-3 and 6G1-30K-4 are likely caused by the destruction of physiological balance in normal embryonic development, which may lead to lower hatchability of the temperature sensitive strain. The results suggest that reasonable metabolism of 30K proteins is a prerequisite for the embryo's normal development.

All-polymer electrostrictive systems are developed. Two typical electro-active polymers, poly(vinyldiene- trifluoroethylene) P(VDF-TrFE) of high elastic modulus and polyurethane of low elastic modulus, are studied. The conducting polymers used as electrodes in the system are polypyrrole and polyaniline respectively. The compatible interface between the electrode polymer and electrostrictive polymer produces acoustic transparency of the all-polymer films. The dielectric and electromechanical properties of the system are characterized and compared with that of the electroactive polymer with gold electrodes. It is found that the dielectric loss of the system is a litter bit higher than that of the sample with gold electrodes at high frequency since the conductivity of the conductive polymer is lower than that of the gold. The electric field induced longitudinal strain response of the all-polymer system is the same as that of the electroactive polymer with gold electrodes. However, the electric field induced transverse strain response of the all-polymer system is higher than that of the electroactive polymer with gold electrodes.

Conditions operatoires qui donnent le rendement maximal en produit intermediaire, en fonction du rapport de recuperation du reactif et du rapport des constantes de vitesses. Comparaison des rendements d'un reacteur parfaitement agite et d'un reacteur piston