Search

We previously reported that P-retigabine (P-RTG), a retigabine (RTG) analogue bearing a propargyl group at the nitrogen atom in the linker of RTG, displayed moderate anticonvulsant efficacy. Recently, our further efforts led to the discovery of HN37 (pynegabine), which demonstrated satisfactory chemical stability upon deleting the ortho liable -NH2 group and installing two adjacent methyl groups to the carbamate motif. HN37 exhibited enhanced activation potency toward neuronal Kv7 channels and high in vivo efficacy in a range of pre-clinical seizure models, including the maximal electroshock test and a 6 Hz model of pharmacoresistant limbic seizures. With its improved chemical stability, strong efficacy, and better safety margin, HN37 has progressed to clinical trial in China for epilepsy treatment.

Fructus Sophorae (FS), the dry mature fruit of Sophora japonica Leguminosae, is a valuable traditional Chinese medicine resource with flavonoids as the major active ingredients. To identify the plant-derived estrogen-like flavonoids serving as potential osteoporosis chemopreventive agents, we isolated and identified 27 flavonoids compounds, including 17 compounds obtained for the first time from FS. To screen out the flavonoids with estrogen-like biological behavior from the 11 high yield compounds, we set up an in vitro screening system in rat osteoblast MC3T3-E1 cells including MTT assay, alkaline phosphatase staining and Alizarin red S staining assay to examine the effects on cell proliferation, differentiation and mineralization of osteoblast cells respectively. Six flavonoids, including genistein, sophoricoside, sophorabioside, sophoraflavonoloside, nicotiflorin and rutin, significantly increased the cellular activity of MC3T3-E1 cells. Furthermore, blocking the estrogen receptor signaling by tamoxifen compromised the effects above significantly, suggesting the 6 compounds behave as estrogen-like reagents. Moreover, the interaction between the six flavonoids from FS and estrogen receptor was clarified by molecular docking method from Glide XP. Collectively, being used as food and medicine in China, FS is rich in flavonoids with estrogen-like effects, may be used as healthy supplementary in treating postmenopausal women osteoporosis.

A three-dimensional heat transfer numerical model is proposed here for the soft-body caterpillar-like robots to present insights for biologists and engineers understanding heat-induced locomotion of these robots. Thermal field distribution of the soft robot body made by the polymer composites is firstly modeled by the use of computational fluid dynamic methodology. The computed spatial distributions of thermal fields were subsequently compared with experimental ones. The achieved agreement between numerical and experimental results further validated the numerical methodology well. Uniformity of thermal field, uniformity factors and typical temperatures for the soft robot body are numerically calculated in details. The results demonstrated that power density P, body size W and thermal conductivity (graphite content) κr have significant effects in the spatial distributions of heat transfer. Furthermore, the specific volume ratio and optimal structural configuration of the heating sources (GS composites: graphene sheets and pliable polydimethylsiloxane) and substrates (pure PDMS: polydimethylsiloxane) are determined upon that the maximum elongation is achieved at different operation conditions of P, W and κr respectively. Present research could contribute to the remotely powered and controlled soft robots made by polymer composites.

A dynamic SOEC (Solid Oxide Electrolysis Cell) model is proposed to investigate the transient response and steady performance of a planar SOEC. Three representative types of continuity equation expressions are systematically compared for the simulation of source terms introduced by electrochemical reactions. For the conservative form of continuity equation (Type A), reasonable predictions at both sides of cathode and anode cannot be achieved, as the diffusion effect is neglected. The non-conservative form of continuity equation (Type B) can obtain reasonable prediction for the cathode side but poor prediction for the anode side. The Type C of continuity equation, newly proposed by the authors for modeling the SOECs, is based on the law of volume conservation. It could achieve the volume increment (oxygen produced) at the anode compartment and good agreements with the analytical ones. It is also found that continuity equations significantly influence the fluid flow and mass transport, whereas their effects on the electrical characteristics are negligible when the global current density is not high.

C26H41NO5, orthorhombic, P212121 (no. 19), a = 9.6178(8) Å, b = 13.3335(11) Å, c = 19.0758(16) Å, V = 2446.3(4) Å3, Z = 4, R gt(F) = 0.0389, wRref (F2 ) = 0.0888, T = 296(2) K.

Regarding the mixed ionic-electronic conductive electrolytes, there are several constant assumptions about cell resistances and transference numbers. In this work, the charge transport frameworks of mixed conductive SOCs are comprehensively illustrated. And the independent external current density is introduced into the equivalent circuit for considering the variations of cell resistances under load. The updated expressions of cell resistances together with transference numbers are deduced rigorously based on the equivalent circuit. Electrolyte-supported NiO-GDC/GDC/LSCF cells are tested, and the experimental results validate the variations of cell resistances, especially for the polarization resistance. The comparisons show that electron hole resistances together with transference number calculated by the updated expressions are larger than those obtained by Liu’s method. More accurate transference number and cell resistances under load can be achieved by using the proposed method in this study.

Visible-light-driven WO3and#183;0.33H2O/Ag2MoO4 composites have been prepared by using an in-situ growth of Ag2MoO4 nanoparticles on the surfaces of WO3and#183;0.33H2O. The photocatalytic activities of the samples were studied by degradation of rhodamine B and levofloxacin dilute solution. The synergistic photocatalytic mechanism was also analyzed. Experimental results reveal that the as-developed hybrids have higher photocatalytic activity than pure samples. When the theoretical molar ratio of WO3and#183;0.33H2O to Na2MoO4and#183;2H2O is 1:0.15, the as-developed hybrids have the highest photocatalytic degradation efficiency of 99.0% for rhodamine B in 45 min and 40.9% for levofloxacin in 120 min. Furthermore, there are chemical bonds between WO3and#183;0.33H2O and Ag2MoO4. In addition, the super oxide radicals play the leading role during the photocatalytic degradation process of the samples. This work will provide reference for treatment of organic dyes and antibiotics pollution in water with using solar energy.

Effect of digestion methods on fluorescence intensity of fluorescent polystyrene (PS) beads was poorly understood, which may affect the accuracy of toxicity test of the fluorescent PS beads exposed to marine organisms. Therefore, six digestion approaches were compared on fluorescence intensities and properties of three commercial fluorescent PS beads. Among all the protocols, the digestion using KOH (10% w/v, 60 °C) (KOH-digestion) had no effect on the fluorescence intensity, morphology and composition of the three fluorescent PS beads. Moreover, the extraction efficiency ≥ 95.3 ± 0.2% of fluorescent PS beads in Daphnia magna and zebrafish, confirming its feasibility in fluorescent PS beads quantitative analysis. However, the fluorescence intensities of fluorescent PS beads digested by other five protocols were significantly decreased, as well as the change of morphology and composition on fluorescent PS beads. Overall, the KOH-digestion is an optimal protocol for extracting fluorescent PS beads in biological samples.

A novel tetranorditerpenoid, sinubatin A (1) (having an unprecedented carbon skeleton), a new norditerpenoid, sinubatin B (2) (a 4,5-epoxycaryophyllene possessing an unusual methylfuran moiety side chain), and a known diterpenoid, gibberosin J (3) were isolated from soft coral Sinularia nanolobata. The structures of the new compounds were elucidated by extensive analysis of spectroscopic data.

TGZ10A-40.5 wall bushing of high voltage switch cabinet from one company was taken as applied research object. Reference the development process of high voltage cable shielding technology, three samples were designed and produced depending on different sets of the shield system. The result show that: surfaces processed by the way that the inner (aluminum cylinder) and the outer (metal mesh ring) shielding components were coated with a semi-conductive material, made little sense to improve the withstand voltage level and reduce the partial discharge; surface processed by the way that inner shield component (aluminum cylinder) was coated with semi-conductive material, the outer shield component (metal mesh ring) was not coated with semi-conductive material, was obviously influenced the improvement of the withstand voltage level and reduction of the partial discharge, compared with traditional technology, the average start voltage of corona increased 23.8%, the average value of partial discharge dropped 27.7%.

The treatments of dyes (acid, basic and reactive dyes) wastewater were studied by applying individual coagulation/flocculation (CF) and nanofiltration (NF) processes as well as their combination (referred as CF–NF). For the treatment of highly concentrated multiple dyes wastewater (MDW, 1000 ppm), polyaluminum chloride (PAC) and polydiallyldimethyl ammonium chloride (PDDA) were found to be the most effective coagulant and flocculant, respectively. The CF process can achieve about 90% of dye removal at the optimal dosage of PAC/PDDA=400/200 ppm, and the MDW with pH>3 is favorable for the CF treatment. A positively charged NF hollow fiber membrane was fabricated and used for NF treatment. It is able to remove almost 100% dyes with a permeate flux of about 1.0 L m−2 h−1 under an operating pressure of 1 bar. The combination of CF and NF can complement each other׳s strengths and overcome their individual limitations. The NF treatment can completely remove the strong color left in CF treated dye solutions, while the efficiency of coagulant/flocculant is improved by treating NF concentrated streams and subsequently results in much less sludge. In addition, membrane fouling is abated and NF permeate flux is increased by applying the CF process as a pretreatment. Thus, the combination of CF–NF improves the overall performance for the dyes wastewater treatment.

The small-molecule inhibitors of p53–murine double minute 2 interaction, such as Nutlin-3, are effective against cancers bearing wild-type p53. However, murine double minute 2 inhibitors often are unable to completely eliminate solid tumor cells. To address this issue, we investigated the anticancer effects of Nutlin-3 in combination with Oridonin in osteosarcoma cells. We found that Oridonin at sub-toxic concentrations synergistically enhanced Nutlin-3-mediated cell viability inhibition in wild-type p53 U2OS and SJSA-1, but not in p53-mutant MNNG/HOS and in null-p53 Saos-2 osteosarcoma cell lines. Importantly, in the presence of Oridonin, Nutlin-3 could completely abolish cell viability in the wild-type p53 osteosarcoma cell lines. Western blotting analysis showed that Oridonin treatment rapidly and distinctly increased the levels of all three forms of Bim and also markedly reduced the levels of Bcl-2 and Bcl-xl in osteosarcoma cells. Western blotting analysis further showed that Oridonin considerably enhanced Nutlin-3-triggered activation of caspases-9 and -3 and poly(ADP-ribose) polymerase cleavage. Flow cytometry assay showed that Oridonin significantly enhanced Nutlin-3-mediated apoptosis in wild-type p53 osteosarcoma cells. Overall, our results suggest that the combined treatment of Nutlin-3 plus Oridonin may offer a novel therapeutic strategy for osteosarcoma.

Polymers of intrinsic microporosity, specifically PIM-1, have emerged as promising materials for gas separation due their high gas permeability. However, its insolubility in common polar aprotic solvents like N-Methyl-2-pyrrolidone (NMP) limits its full potential and possible industrial applications. In this study, the solubility of PIM-1 in such solvents has been modified by carboxylation via hydrolysis reaction in a short period of 1 h. The success of carboxylation was verified by nuclear magnetic resonance (NMR) spectroscopy, Fourier transform infrared spectroscopy (FTIR) and water contact angles. The carboxylated PIM-1 (cPIM-1) was subsequently blended with Torlon to enhance the intrinsic permeability of Torlon rich membranes and the intrinsic selectivity of cPIM-1 rich membranes. The additions of 5, 10 and 30 wt% cPIM-1 into Torlon increase its CO2 permeability by 26%, 128% and 791%, respectively, from the original value of 0.541–0.682, 1.233 and 4.822 (1 Barrer=1 × 10−10 cm3(STP) cm/cm2 s cmHg=3.348 × 10−19 kmol m/m2 s Pa) with minor sacrifices in CO2/CH4 selectivity. These permeability improvements are attributed to the formation of hydrogen bonding and charge transfer complexes (CTC) between cPIM-1 and Torlon, which promotes better interactions in the blends. In addition, all the cPIM-1/Torlon membranes exhibit a great plasticization resistance up to 30 atm. This is ascribed to the incorporation of the rigid Torlon that may lead to restricting chain mobility in CO2 environments. The overall separation performance has been driven closer to the Robeson upper bound for O2/N2, CO2/CH4, CO2/N2 and H2/N2 separations. Therefore, the newly developed membranes may have great potential for energy development and industrial applications.

The nitrogen doped nanoTiO2 was prepared by the microwave-assisted method. The properties were characterized by the X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The effects of the calcination temperature and the doping amount of nitrogen on the nitrogen doped nanoTiO2 crystal phase and its photocatalytic properties were studied. The result indicated that with the increase of the calcination temperature, the proportion of rutile in the mixed crystal phases increased gradually. When the calcination temperature was 650°C, the pure rutile phase appeared. When the TiO2 was calcinated at 400 °C, the particle size was the minimum (17nm). This mixed crystal was conducive to the good photocatalytic properties of nanoTiO2. The degradation rate of methyl orange was 50.86%. At the calcination temperature of 450 °C, the proportion of rutile in the mixed crystal phase increased first and then decreased, until finally it increased again with the increase of the doping amount of nitrogen. When the ratio of nitrogen to titanium was 1:0.5, the catalytic effect was the best. The photocatalytic degradation efficiency was 71.63%, and the particle size was also approximately the minimum (15nm).

The nano-TiO2 was prepared by adding surfactant chitosan and sodium dodecyl benzene sulfonate (DBS) under hydrothermal conditions. The influence of chitosan and DBS on the crystal form and photocatalytic properties of TiO2 was discussed. Chitosan acted as the chelant in the reaction, while DBS played the function of preventing aggregation of powder and increasing the degree of crystallization. The fixed calcination temperature was 500°C. The crystallite size could reach about 40.1nm upon the addition of 1g chitosan, and the catalytic efficiency was 51.89%. The crystallite size was about 45.8nm upon the addition of 1g DBS, and the catalytic efficiency was 48.13%. The nano-TiO2 had smaller particle size when chitosan was added under the same reaction conditions.

Natural convection conjugated by two partial enclosures, connected by refrigerator/heater, has been numerically studied. Thick walls facing the opening are heated in one zone and cooled in the other zone respectively by constant heat fluxes. The isothermals, streamlines and heatlines are presented for varied governing parameters, Rayleigh numbers, Ra from 103 to 107, solid thick walls to fluid thermal conductivity ratio λS from 0.01 to 10.0, cavity aspect ratio, Ar from 1.0 to 8.0, and refrigeration coefficient, COR from 0.1 to 10.0. The streamlines and heatlines visualize the real fluid flow and heat transfer process or structures. Anti-clock streamlines are generated in both zones. Variations of extreme temperatures, Tmax or Tmin and dimensionless volumetric flow rate on the opening, M, along with these governing parameters are also presented in tables or figures. Correlations of extreme temperatures with Ra, λS and COR are given for varied Ar. At last, the unified correlations of with those parameters also are presented and analyzed. The results show that the common trends and characteristics of heat and fluid flow independent of Ar for both zones are summarized, though the convection is amplified with increased Ar.

Polymers of intrinsic microporosity (PIM-1) have received worldwide attention but most PIM-1 researches have been conducted on dense flat membranes. For the first time, we have fabricated PIM-1/Matrimid membranes in a useful form of hollow fibers with synergistic separation performance. The newly developed hollow fibers comprising 5–15 wt% of highly permeable PIM-1 not only possess much higher gas-pair selectivity than PIM-1 but also have much greater permeance than pure Matrimid fibers. Data from positron annihilation lifetime spectroscopy (PALS), field emission scanning electron microscopy (FESEM) and apparent dense layer thickness indicate that the blend membranes have an ultrathin dense layer thickness of less than 70 nm. PIM-1 and Matrimid are partially miscible. The effect of partial miscibility on dense selective layer was studied. Defect-free hollow fibers with gas pair selectivity more than 90% of the intrinsic value can be spun directly from dopes containing 5 wt% PIM-1 with proper spinning conditions, while post annealing and additional silicone rubber coating are needed for membranes containing 10 and 15 wt% PIM-1, respectively. Comparing to Matrimid, the CO2 permeance of as-spun fibers containing 5 and 10 wt% PIM-1 increases 78% and 146%, respectively (e.g., from original 86.3 GPU (1 GPU=1×10−6 cm3 (STP)/cm2 s cmHg=7.5005×10−12 m s−1 Pa−1) to 153.4 GPU and 212.4 GPU) without compromising CO2/CH4 selectivity. The CO2 permeance of the fiber containing 15 wt% PIM-1 improves to 243.2 GPU with a CO2/CH4 selectivity of 34.3 after silicon rubber coating. Under mixed gas tests of 50/50 CO2/CH4, this fiber shows a CO2 permeance of 188.9 GPU and a CO2/CH4 selectivity of 28.8. The same fiber also has an impressive O2 permeance of 3.5 folds higher than the pristine Matrimid (e.g., from original 16.9 GPU to 59.9 GPU) with an O2/N2 selectivity of 6.1. The newly developed membranes may have great potential to be used for natural gas purification, air separation and CO2 capture.

Hydro-thermal method was applied to synthesize nanoTiO2particles doped with metal and non-metallic elements. nanoTiO2particles were doped at different calcinations temperatures with S and Fe, Ce and La, respectively. X-ray diffraction results indicated that the minimum diameter of nanoTiO2doped with Ce and S was about 7.2nm, which is smaller than other type of double-element doped nanoTiO2. In addition, with the increase of calcinations temperature, the size of nanoTiO2particle increased and the diameter of nanoTiO2doped with Fe and S was the most obvious one. Rhodamine B was used to simulate the pollutant to analyze the photocatalytic property of doped nanoTiO2. The results indicated that the degradation rate of rhodamine B by nanoTiO2doped with La and S under the calcinations temperature of 450 °C reached66.22%.

The nano manganese oxides were prepared with the hydrothermal method by adding surface-active agent. The influence of the type and addition amount of surface-active agent on the preparation of nano manganese oxides was studied. The products were characterized with XRD. Experimental results show that MnOOH is obtained at 180°C with the addition of N,N,N-trimethyl-1-dodecanaminium bromide, and Mn3O4is obtained at 180 °C with OP Emulsifier or Tween-80 added. Different addition amount of surface-active agent would have diverse effects on the purity of products.

Ultraviolet (UV)-rearranged PIM-1 membranes have been shown to exhibit superior gas separation performance for H2/CO2 separation. The long-term aging studies of up to 100 days were investigated and revealed that the UV-rearranged PIM-1 membranes are much more stable than the original PIM-1 membrane. By positron annihilation lifetime (PAL) analyses, a constant decrease of o-Ps lifetime during physical aging of all membranes was observed, while o-Ps intensity changed sparingly. Compared to pure gas tests, the UV-irradiated PIM-1 membrane shows considerably enhanced separation performance in mixed gas tests with and without CO under high temperatures. Although the UV-rearranged PIM-1 membranes reveal deteriorating gas separation performance under humid feed conditions due to the effect of water vapor induced plasticization, the overall gas separation performance still outperforms most literature data. The successful validation of the separation performance for the UV-rearranged PIM-1 membranes under similar industrial testing conditions may possibly suggest the great potential of this type of membrane for the purification and production of industrial hydrogen.

Most of research on formation mechanism of black silicon stays in the stage of experimental analysis. Consequently, it is quite difficult to perceive the mechanism of its formation process theoretically. In this paper, Quantum Mechanics is involved in our research on mechanism of how black silicon is formed in the fabrication process based on DRIE. Satisfying result is obtained through our simulation: Pillar structures with spacing raging from 500nm to 550nm can be formed when there exist particles with single momentum size in emulated experiment environment; With further efforts, more complicated pillar structures are obtained assuming that there exist particles with two sizes of momentum. By comparing with SEM image of black silicon, the simulated pillar structures are quite similar with real black silicon in both spacing and height distribution.

This paper reviews the material design and fabrication of a class of membranes where some larger molecules can permeate faster than smaller ones, or so-called reverse-selective membranes, for conventional gas or vapor separation applications. The main requirements for a good reverse-selective gas or vapor separation membrane are high permeability, good separation capability, stable performance and sufficient mechanical properties to withstand the harsh environments in commercial separation processes. High permeability in reverse-selective membranes is achieved by tuning the fractional free volume (FFV) content, i.e., free spaces for penetrant diffusion, while facilitating preferential interaction between functional moieties of the membrane material and penetrant molecules to enhance penetrant sorption, and suppressing crystallinity where applicable. The separation capabilities of these membranes are generally controlled by the preferential sorption of larger condensable penetrants over smaller penetrants rather than size-selective diffusion common for conventional gas separation polymers. Reverse-selective gas separation membranes have attracted much attention owing to their advantages for certain commercial gas separation applications. This review summarizes the different aspects of polymeric reverse-selective gas separation membranes reported in the literature and comments briefly on their commercialization potential.

The paper gains a new method for the synthesis of γ-MnOOH crystals by adding ethylenediamine metal complexes under hydrothermal conditions. Study the effect of different preparation process to the reaction products .The structure and morphology of the resultant products were characterized by using XRD, SEM. The results show that the product is α-MnO2 when did not join the ethylenediamine metal complexes and the product is γ-MnOOH when joined the ethylenediamine metal complexes in 100°C under hydrothermal conditions. The purity of the γ-MnOOH is not the same when adding different ethylenediamine metal complexes. Inorganic salts will reduce the purity of the product and a new Mn3O4 crystal can be prepared by increasing the reaction temperature to 180°C.

Sol-gel method was applied to synthesize nano-TiO2 particles doped with metal and non-metallic elements. Nano-TiO2 particles were doped at different calcinations’ temperatures with S and Fe, Ce and La, respectively. A comparison was performed on the effect of different metallic elements on nano-TiO2 particles doped with the same non-metallic element S. X-ray diffraction results indicated that the diameter of doped nano-TiO2 particle was smaller than that of non-doped nano-TiO2 particles. The minimum diameter of nano-TiO2 doped with Ce and S was about 8nm, while that of nano-TiO2 doped with La and S was about 9nm. The minimum diameter of nano-TiO2 particles doped with Fe and S was about 10nm. In addition, with the increase of calcinations’ temperature, the size of nano-TiO2 particle increased. All nano-TiO2 particles doped with double elements were antae. Methyl orange was used to simulate the pollutant to analyze the photocatalytic property of doped nano-TiO2. The results indicated that the doped element had some effect on the photocatalytic property of nano-TiO2, and varied for different doped metallic elements. Among them, the degradation rate of methyl orange by nano-TiO2 doped with La and S under the calcinations’ temperature of 550 °C reached 28.97%.

A series of hyperbranched polyimides (HBPI) were selected as precursors for the production of carbon molecular sieve membranes (CMSMs) and the gas separation performance of the resultant CMSMs was explored. By varying the monomer compositions of HBPI precursor polymers, the influences of degree of branching on pore size and distribution of the CMSMs are investigated and examined. A CO2 permeability of 1085 Barrer with CO2/CH4 selectivity of 52 is attained. Thermal analyses reveal that the chain rigidity of the precursors increases with the degree of branching, while the density of the CMSMs shows an opposite trend. In view of the unique network structure offered by the HBPI precursors, it is speculated that the rigid network of the HBPI with the highest degree of branching has facilitated the formation of ultra-micropores, giving rise to the more constrained structure and improved diffusivity selectivity. The unique hyperbranched network structure found in HBPI possesses great potential to producing CMSMs with superior performance.

Phloretin, a natural component of many fruits, exhibits anti-virulence effects and provides a new alternative to counter bacterial infection. The aim of this study was to determine the effect of subinhibitory concentrations of phloretin on the virulence of Salmonella typhimurium. At concentrations where growth of Salmonella was not inhibited, phloretin significantly inhibited bacteria biofilm formation and motility. Subinhibitory concentrations of phloretin repressed eight genes involved in the Salmonella pathogenicity island 1 and 3 genes involved in flagella production. Furthermore, subinhibitory concentrations of phloretin inhibited the adhesion and invasion of Salmonella in IEC-6 cells and reduced the LDH levels of S. typhimurium-infected IEC-6 cells. Additionally, phloretin significantly decreased the cecum bacterial loads of the mice infected with live S. typhimurium containing subinhibitory concentrations of phloretin by gavage. These results suggested that subinhibitory concentrations of phloretin attenuate the virulence of S. typhimurium and protect against S. typhimurium infection.

Polymers of intrinsic microporosity (PIM-1) have been known for their super high permeability but average selectivity for medium-size gas pairs. They have unimpressive selectivity for H2 and CO2 separation (i.e., α (H2/CO2) = 0.6). For the first time, we have discovered that ultraviolet (UV)-rearranged polymers of PIM-1 membranes can be used for H2/CO2 separation with far superior separation performance to others in literatures. The PIM-1 membrane after UV radiation for 4 hours shows H2 permeability of 452 barrer with H2/CO2 selectivity of 7.3. Experimental data and molecular simulation reveal that the polymer chains of PIM-1 undergo 1,2-migration reaction and transform to close-to-planar like rearranged structure after UV radiation. As a result, the UV-irradiated PIM-1 membrane shows considerable drops in both fractional free volume (FFV) and size of micro-pores. Positron annihilation lifetime (PAL) results have confirmed the chemical and structural changes, suggesting the FFV and pore size drops are mainly ascribed to the destructed spiro-carbon centre during UV radiation. Sorption and x-ray diffractor (XRD) analyses indicate that the impressive H2/CO2 selectivity arises from the significantly enhanced diffusivity selectivity induced by UV radiation, followed by molecular rearrangement, conformation change and chain packing.

The polymers of intrinsic microporosity have gained the attention as one of the potential materials for membrane gas separation. The contorted ladder-like structure in polymers of intrinsic microporosity, specifically PIM-1 possesses high permeability but with moderate selectivity for O2/N2, CO2/N2 and CO2/CH4 separation. We report here the most convenient and time efficient strategy of tuning the permeability and selectivity by blending PIM-1 with different compositions of Matrimid. In this work, the physical properties, phase behavior and gas transport properties of PIM-1/Matrimid blends have been explored. The polarized light microscope (PLM) analyses evidence that most of the PIM-1/Matrimid blends reveal partially miscible behavior. The inclusion of PIM-1 in the Matrimid matrix results in a substantial increase in gas permeability and a slight decrease in selectivity. The additions of 5 and 10 wt% PIM-1 into Matrimid induce the permeability increments of 25% and 77%, respectively from the original 9.6 to 12 and 17 Barrer without compromising its CO2/CH4 selectivity. For O2/N2 separation, the incorporation of a small amount of Matrimid (e.g., 5–30 wt%) into PIM-1 promotes a fair increase in selectivity and drives the overall gas separation performance surpassing or close to the upper bound. At binary gas tests of CO2/CH4 (50%/50%), the 30 wt% PIM-1 in Matrimid membrane has a CO2 permeability of 50 Barrer and a CO2/CH4 selectivity of 31.

Novel thermally self-cross-linked polymers of intrinsic microporosity (PIM-1) membranes have been prepared by postmodification of PIM-1 at the elevated temperature for a period of 0.5–2 days. The occurrence of cross-linking reaction has been verified by thermogravimetric analysis (TGA), X-ray photoelectron spectrometer (XPS) and gel content analyses. TGA analyses indicate an increase in thermal stability of membranes after the thermal cross-linking treatment. There is also an obvious drop in the maximum decomposition rate comparing to the original PIM-1when membranes are thermally treated for an extended period of time. Both FTIR and XPS results suggest that the nitrile-containing PIM-1 membranes undergo a latent cross-linking reaction, and form stable bulky triazine rings. The resultant cross-linked polymeric membranes exhibit exceptional gas separation performance that surpasses the most recent upper bound of state-of-the-art polymeric membranes for the important gas separations, such as hydrogen purifi...

Climatological mean and annual variations of Chlorophyll-a (Chl-a) distribution, sea surface wind (SSW), and sea surface temperature (SST) from 1998 to 2008 were analyzed in the middle of the South China Sea (SCS), focusing on the typical region off the east coast of Vietnam (8.514°N, 109.5114°E). Based on remote sensing data and SCS summer monsoon index (SCSSMI) data, high Chl-a concentrations in the middle of the SCS in the southwest summer monsoon season (JuneSeptem- ber) may be related to strong Ekman pumping and strong wind stress. The maximum of the monthly averaged cli- matological Chl-a in the summer appeared in August. According to the annual variation, there was a significant negative correlation (r = 0.42) between the SCSSMI and SST, a strongly positive correlation (r=0.61) between the SCSSMI and Chl-a, and a strongly negative correlation (r = 0.74) between the SST and Chl-a in the typical region off the east coast of Vietnam during 19982008. Due to the El Nino event specifically, the phenomena of a low Chl-a concentration, high SST and weak SCSSMI were extremely predominant in the summer of 1998. These relationships imply that the SCSSMI associated with the SST could be used to predict the annual variability of summer Chl-a in the SCS.  Keywords: Chlorophyll-a, monsoon, South China Sea, annual variability Citation: Yang, Y.-J., T. Xian, L. Sun, et al., 2012: Sum- mer monsoon impacts on Chlorophyll-a concentration in the middle of the South China Sea: Climatological mean and annual variability, Atmos. Oceanic Sci. Lett., 5, 15-19.

Simultaneous transport of heat and moisture by conjugate natural convection in a partial enclosure with a solid wall is investigated numerically. Moist air motions are driven by the external temperature and concentration differences imposed across enclosures with different ambient moisture conditions. The Prandtl number and Schmidt number used are 0.7 and 0.6, respectively. The fluid, heat and moisture transports through the cavity and solid wall are, respectively, analyzed using the streamlines, heatlines and masslines, and the heat and mass transfer potentials are also explained by the variations of overall Nusselt and Sherwood numbers. The numerical simulations presented here span a wide range of the main parameters (heat and mass diffusion coefficient ratios, solid wall thickness and thermal Rayleigh numbers) in the domain of aiding and opposing buoyancy-driven flows. It is shown that the heat transfer potential, mass transfer potential, and volume flow rate can be promoted or inhibited, depending strongly on the wall materials and size, thermal and moisture Rayleigh numbers.

Free heat and mass transfer during drying in a porous enclosure with free vents has been investigated numerically. Enclosed moist air interacts with the surrounding air through freely vented ports situated on both sides perpendicular to the heated wall. Air, heat, and moisture transport structures are visualized respectively by streamlines, heat lines, and mass lines. Effects of thermal Rayleigh number, Darcy number, vent location, and enclosure inclination on the convective heat/moisture transfer rate and volume flow rate across this enclosure are discussed. For each case, partially enclosed fluid flow undergoes different phases, increasing with buoyancy ratio; that is, heat transfer–driven flow, heat- and moisture-aided flow, and moisture transfer–dominated flow. Numerical results demonstrate that the convective heat and moisture transport patterns and transport rates greatly depend on thermal Rayleigh number, properties of porous medium, and enclosure inclination. Practices for enhancing heat and moist...

This study numerically explores the diffusion rules of pollutants in an idealized urban street canyon where photochemical reactions are present in the neighbourhood. The airborne pollutants dispersion and reaction in street canyons are further investigated in this study. There is a relatively tense traffic pollutants release in urban neighborhoods, including nitrogen oxides and hydrocarbons. Photochemical reaction occurs at strong solar radiation, forming photochemical smog and other environment issues. We selected typical O3 + NO→O2 + NO2 reactions. Effects of the pollutant source location on pollutant dispersion and reaction are also investigated. Numerical simulations were conducted on chemically activity reactive air nitrogen oxides in urban street canyons with W (street canyon wide)/H (building height) = 1. Provided three different locations from the line source street canyon bottom exhaust nitric oxide diffusion and react with ozone in the free stream. The chemical reaction has a significant impact on the concentration of pollutants in the valley volume.

In this article, we selectively extracted the nuclear matrix and intermediate filament system of human neuroblastoma SK-N-SH cells pre- and post-treated with retinoic acid (RA). The distribution of nucleophosmin (NPM) in the nuclear matrix and its colocalization with several products of related genes were investigated. Results from two-dimensional gel electrophoresis and MALDI-TOF showed that NPM was a component of the nuclear matrix and its expression in SK-N-SH cells post-treated with RA was down-regulated. Immunofluorescent microscopy observations further showed that NPM was localized in the nuclear matrix of SK-N-SH cells, and its expression level and distribution were altered after treatment with RA. The colocalization of NPM with c-myc, c-fos, p53, and Rb in SK-N-SH cells was observed under a laser scanning confocal microscope, but the colocalization region was changed by RA. Our results prove that NPM is a nuclear matrix protein, which is localized in nuclear matrix fibers. The colocalization of NPM with its related genes and oncogenes affect the differentiation of SK-N-SH cells. The expression of NPM and its distribution in the process of cell differentiation deserve more intensive investigation.

Poly(p-dioxanone) (PPDO) is a useful biomaterial and potential ecomaterial due to its biodegradability and good mechanical properties. Like other aliphatic polyesters, however, it has a low crystallization rate and low melt strength; it is difficult to produce thin films from it by blown film processing. In this work, poly(p-dioxanone)/montmorillonite (MMT) nanocomposites have been prepared successfully by in situ ring-opening polymerization of p-dioxanone and MMTs. The novel, biodegradable nanocomposites have a remarkably increased crystallization rate and melt strength; moreover, they can be blown into thin films, which have excellent mechanical properties. A typical sample showed a tensile strength of 59.2 MPa and elongation at break 605%.

Montmorillonites modified by hydroxyethylhexadecyldimethyl ammonium bromine were used to prepare poly(ϵ-caprolactone) (PCL)/montmorillonite (MMT) nanocomposites by in situ ring-opening polymerization of ϵ-caprolactone. Wide-angle X-ray diffraction (WAXD) analysis illustrated that an exfoliated structure of PCL/MMT nanocomposite was obtained. The nonisothermal crystallization kinetics of poly(ϵ-caprolactone) and PCL/MMT nanocomposite was investigated by differential scanning calorimetry (DSC) at various cooling rates. The values of half-time of crystallization (t1/2) and crystallization rate constant (Zc) showed that crystallization rate increased with the increase of cooling rates for both PCL and PCL/MMT nanocomposite; however, the crystallization rate of PCL/MMT nanocomposite was faster than that of PCL at a given cooling rate.

Purpose The purpose of this study was to evaluate the outcomes of sclerotherapy of maxillofacial venous malformations by use of absolute ethanol and pingyangmycin (bleomycin A 5 hydrochloride). Patients and Methods We treated 23 consecutive patients with maxillofacial venous malformations by sclerotherapy with a combination of absolute ethanol and pingyangmycin under local anesthesia. The size of the lesions ranged from 2 cm × 2 cm to 12 cm × 10 cm. Venography showed the presence of large venous lakes. Venograms were obtained during the first procedure before and after injection of absolute ethanol (0.5-2.5 mL) to confirm the site of the nidus and assess the effect of sclerosis of the nidus and draining veins. Subsequently, 8 to 16 mg of pingyangmycin dissolved in 40 mL of saline solution was infused into the nidus by a dynamic infusion pump at a rate of 1 mL/min. If necessary, this procedure was repeated once in 2 or 4 weeks. The clinical outcomes and complications were evaluated. Results The duration of follow-up ranged from 6 to 37 months, with a mean of 20.3 months. Only 1 procedure was required in 3 patients, and the procedure was required to be repeated twice in 9 patients, 3 times in 7, and 4 times in 4. All the patients were satisfied with the treatment results, and excellent clinical results were obtained in 9 patients. There was no skin necrosis or nerve damage. Conclusions Percutaneous sclerotherapy with the combined use of absolute ethanol and pingyangmycin is a safe and effective treatment for maxillofacial venous malformations.

Solder interconnect reliability is influenced by environmentally imposed loads, solder material properties, and the intermetallics formed within the solder and the metal surfaces to which the solder is bonded. Several lead-free metallurgies are being used for component terminal plating, board pad plating, and solder materials. These metallurgies react together and form intermetallic compounds (IMCs) that affect the metallurgical bond strength and the reliability of solder joint connections. This study evaluates the composition and extent of intermetallic growth in solder joints of ball grid array components for several printed circuit board pad finishes and solder materials. Intermetallic growth during solid state aging at 100°C and 125°C up to 1000 h for two solder alloys, Sn-3.5Ag and Sn-3.0Ag-0.5Cu, was investigated. For Sn-3.5Ag solder, the electroless nickel immersion gold (ENIG) pad finish was found to result in the lowest IMC thickness compared to immersion tin (ImSn), immersion silver (ImAg), and organic solderability preservative (OSP). Due to the brittle nature of the IMC, a lower IMC thickness is generally preferred for optimal solder joint reliability. A lower IMC thickness may make ENIG a desirable finish for long-life applications. Activation energies of IMC growth in solid-state aging were found to be 0.54 ± 0.1 eV for ENIG, 0.91 ± 0.12 eV for ImSn, and 1.03 ± 0.1 eV for ImAg. Cu3Sn and Cu6Sn5 IMCs were found between the solder and the copper pad on boards with the ImSn and ImAg pad finishes. Ternary (Cu,Ni)6Sn5 intermetallics were found for the ENIG pad finish on the board side. On the component side, a ternary IMC layer composed of Ni-Cu-Sn was found. Along with intermetallics, microvoids were observed at the interface between the copper pad and solder, which presents some concern if devices are subject to shock and vibration loading.

Two-dimensional calculation and theoretical analysis have been performed for laminar natural convection induced by two discrete heating elements flush mounted to one vertical wall of a square enclosure. Two cases are presented in this work. One is the upper elevation Heater-1 fluctuates its temperature as a sinusoidal function while the lower elevation Heater-2 maintains its temperature constant. The other case depicts the opposite situation of interchanging the boundary conditions of Heater-1 and Heater-2 in Case 1. A large range (0.01–10.0) of non-dimensional frequency is conducted numerically, and the results show the existence of resonance frequencies in both cases. Scale analysis over predicts the resonance frequency due to ignoring heat dissipation between the heaters. Mechanical details of the fluid flow and average heat transfer characteristics across Heater-1, Heater-2 and the centerline of the enclosure are scrutinized. The results indicate that in Case 1, the heat transfer of Heater-2 is little affected by the periodic change of temperature of Heater-1. However, the oscillatory behavior is largely intensified in Case 2 owing to the thermal wake generated on Heater-2 invigorating the global flow throughout the enclosure. The heatline concept, flow and temperature fields of the oscillating components are adopted to visualize the heat transport and fluid circulation.

This paper aims to prolong the heat pump frost time and reduce its growth with heat recovery facility, which should mix the exhausted indoor and outdoor air before entering the evaporator. An ideal mathematic model is developed for heat transfer, frost generation and airside pressure drop. The properties of the mixture would be obtained by solving the mass and energy conservation equations. A parametric analysis is performed to investigate the effects of air inlet temperature, relative humidity and air mass flow rate on total heat transfer coefficient, frost thickness and airside pressure drop, respectively. The results show that rationalizing the ratio of indoor and outdoor air could prolong frosting time and reduce the frost thickness greatly. The total heat transfer coefficient, frost thickness and airside pressure drop increase monotonically with time going, but are not proportional. Decreasing the mixture inlet air temperature and relative humidity could essentially reduce frost growth on the tube surfaces. This can also be observed when increasing the air mass flow rate.

Due to the adequate viscosity of the chitosan-added precursor solutions, the films deposited from the chitosan-added precursor solution showed a higher deposition rate than the ones from the PVP-added solution under the same coating parameters. Furthermore, the chitosan-added precursor solution remained stable without any precipitation for at least 10 months. On the other hand, without the addition of chitosan, the precursor solution showed apparent precipitation after being stirred for 12 h. The enhanced stability of the precursor solution by the addition of chitosan is attributed to the complexation between metal ions and the –NH 2 groups of chitosan. And the electrochemical behavior for the deposited films calcined at 700 °C for 1 h was also characterized by charge–discharge test. The result revealed that the film deposited from chitosan-containing precursor solution possesses an initial discharge capacity of 134 mAh g −1 and about 9% capacity loss after 50 charge/discharge cycles, which is better than the one deposited from chitosan-free precursor solution with an initial discharge capacity of 108 mAh g −1 and 24% capacity loss after 50 cycles.

Spinel LiMn 2 O 4 thin-film cathodes were obtained by spin-coating the chitosan-containing precursor solution on a Pt-coated silicon substrate followed by a two-stage heat-treatment procedure. The LiMn 2 O 4 film calcined at 700 °C for 1 h showed the highest Li-ion diffusion coefficient, 1.55 × 10 −12 cm 2 s −1 (PSCA measurement) among all calcined films. It is attributed to the larger interstitial space and better crystal perfection of LiMn 2 O 4 film calcined at 700 °C for 1 h. Consequently, the 700 °C-calcined LiMn 2 O 4 film exhibited the best rate performance in comparison with the ones calcined at other temperatures.

Spinel LiMn 2 O 4 films were obtained by spin-coating the lithium/manganese acetates-containing precursor solution on a Pt-coated silicon substrate. The effect of chitosan addition in the acetates-containing precursor solution on the formation of the LiMn 2 O 4 films was investigated by TG/DTA, FT-IR spectroscopy, glancing-angle XRD and cyclic voltammetry. It was demonstrated that the addition of chitosan is very beneficial to the deposition of a single-phase LiMn 2 O 4 film due to the fact that chitosan is able to chelate with lithium/manganese ions and form a stable complex compound. Moreover, the electrochemical measurements also showed that the deposited LiMn 2 O 4 film from the chitosan-added precursor solution exhibits a higher discharge capacity of 134 mAh/g at 1 C and a better rate performance (86.4% of the discharge capacity at 1 C can be maintained when the discharge rate increases from 1 up to 8 C) in comparison with one from the chitosan-free solution.

Thin film of spinel LiMn 2 O 4 was obtained by spin coating the chitosan-containing precursor solution on a platinumized Si substrate, followed by a two-step annealing procedure at 300 and 700 °C, respectively. It was demonstrated that the addition of the appropriate amount of chitosan to the precursor solution enhanced the deposition of LiMn 2 O 4 films. The thickness of the deposited film from chitosan-containing precursor solution is about 5.2 μm after five-time spin coating under a spinning speed of 2500 rpm. Without the addition of chitosan in precursor solution, the deposited film was as thin as 0.16 μm under the same processing parameters. Furthermore, the electrochemical behavior for the deposited LiMn 2 O 4 film calcined at 700 °C for 1 h was characterized by the charge–discharge test. The result shows that the 1st discharge capacity is 56.31 μAh cm −2 μm −1 at a discharge rate of C /2 and the fading rate of the discharge capacity is only 0.19% cycle −1 after 50 cycles.

The addition of aliovalent element plays an important role on the structural, electrical and electrochemical properties of LaMnO 3 . In this study, 10% of Li was incorporated into the A-site of the LaMnO 3 perovskite. The addition of more than 10% Li resulted in the formation of the LiMn 2 O 4 spinel as a second phase. The conductivity of LaMnO 3 was also effectively enhanced by the addition of Li. The undoped LaMnO 3 exhibits a conductivity of 0.25 Ω −1 cm −1 at 27 °C. In the LaMnO 3 sample doped with 10% Li, the conductivity increased to 2.25 Ω −1 cm −1 at 27 °C. For 30% Li-doped LaMnO 3 , the lower conductivity of 1.31 Ω −1 cm −1 at 27 °C was observed due to the formation of poor-conducting LiMn 2 O 4 . In all the samples doped with Li, the activation energy (17.20–18.17 kJ/mol) for electrical conduction was much lower than that of undoped LaMnO 3 (26.71 kJ/mol). The reduction in activation energy can be rationalized by the creation of electron holes due to the addition of Li. In the sample with the composition of La 0.9 Li 0.1 MnO 3 , the cyclic voltammetry and charge/discharge tests indicated that the sample was not electrochemically active.

Poly(p-dioxanone) (PPDO)/montmorillonite nanocomposites were prepared through the in situ ring-opening polymerization of p-dioxanone (PDO) and three types of montmorillonites (natural sodium montmorillonite, montmorillonite modified by octadecyltrimethyl ammonium chloride, and montmorillonite modified by hydroxyethylhexadecyldimethyl ammonium bromine) in the presence of triethylaluminum. Montmorillonite could accelerate the polymerization of PDO, and the viscosity-average molecular weight of PPDO could reach 44,900 g/mol in 0.5 h. A nucleating effect of montmorillonite was observed, and the crystallization temperature of PPDO was increased by 18 °C. All three montmorillonites could improve the thermal stability of PPDO and increase the glass-transition and melting temperatures of PPDO. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2298-2303, 2005

Near infrared spectroscopy has been considered as a potentially ideal noninvasive technique for the postoperative monitoring of plastic surgery. In this study, 6 flaps were raised on rhesus monkeys’ forearms. Blood and oxygen delivery to these flaps was monitored following vascular occlusions and inhalation of pure oxygen. Optical fibers were adopted in the probe of the oximeter so that the cutaneous detection could be performed in reflectance mode. Different and repeatable patterns of changes were measured following vascular occlusions on flaps. It is clear that the near infrared spectroscopy is capable of postoperatively monitoring vascular problems in flaps, especially the venous problem. Near infrared spectroscopy showed high sensitivity to detect the dynamic changes in flaps induced by inhalation of pure oxygen in this study. The experimental results indicated that it was potential to assess tissue viability utilizing the dynamic changes induced by some noninvasive stimulation (such as inhaling pure oxygen). It may be a new assessing method that is rapid, little influenced by other factors and less inconvenient to patients.