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As one of high energy consumption pumps, pump used for solid-liquid two-phase mixture transportation, such as slurry pump and mud pump, is extensively used in the hydraulic transportation of solid-liquid mixture through pipes in various fields. The erosion wear in slurry pumps has been identified as a critical issue during transportation of slurry as it affects the equipment performance and reduces its reliability and operation life, leading to the waste of energy. Many studies indicate that the performance and efficiency of solid-liquid two-phase centrifugal pump is controlled by the two-phase flow pattern inside the pump, so understanding flow characteristics and abrasion mechanism has important significance to improve the hydraulic design of the impeller for decreasing the abrasion and increasing the service life of the pump. In the present study, based on solid-liquid two-phase flow as object, an improved experimental facility without agitation was developed can improve the test precision by eliminating the influence of agitation on flow inside pump and improving particle-liquid two-phase flow circulation way. On the base of experimental studies, POD methods were applied to analysis the liquid turbulence modulation by solid-particles and the behavior of large eddy structures will be clearly understood. Thus, the theoretical system of the solid-liquid two-phase flow will be further improved. And a theoretical principle for the solid-liquid two-phase pump optimal design will be presented. The following conclusions are obtained: (ⅰ) a superior PIV two-phase test platform than that in the previous literature is designed and it can be very good to realize a stable solid-liquid two-phase flow measurement of centrifugal pump. Compared with the traditional platform, the results obtained by the novel solid-liquid two-phase centrifugal pump PIV test platform has a very high accuracy and it has a good reference value to understand flow mechanism of a centrifugal slurry pump. The two particle images with and without agitating are shown in Figure 5. As can be seen that a large number of bubbles are brought into the circulation line (Figure 5(a)), which is caused by a higher stirring speed for suspending solid particles, and thus the actual flow images shows a gas-liquid-solid three-phase flow. However, for the present test facility without stirring, there is no such problem, and the original image is very clear without bubbles. (ⅱ) The POD analyses show that the solid-particles injection has an important influence on the large scale turbulence structures which contain a large amount of energy. The modal energy distribution as a function of the POD mode number is displayed in Figure 10. The energy contribution of these large scale structures to the total energy becomes larger due to the injection of solid-particles, whereas the contribution of the small scale structures, which denotes the energy dissipation, becomes smaller. This is why the low solid-phase volume concentration has higher pump head and efficiency. The addition of solid-particle increases the friction loss, but reduces the flow separation loss and inhibits the development of small scale vortex. However, with the increase of solid-particle concentration, the friction loss increases is greater than the flow separation loss reduction, and thus pump head and efficiency decrease. The above phenomena show fully that the solid-particles addition has an important influence on the large scale energetic eddy structures. This is confirmed by the measurement results as shown in Figure 11.

A series of Cu-Ce binary oxides were synthesized via a facile co-precipitation method for toluene catalytic oxidation. The physicochemical properties of these samples were characterized by BET, XRD, SEM, TEM, H2-TPR, O2-TPD, and XPS. It reveals that Cu1Ce3 catalyst possesses a higher specific surface area, stronger Cu-Ce synergistic effect, and better low-temperature reducibility than other samples. Moreover, Cu1Ce3 catalyst exhibited superior toluene oxidation activity with 99.10% toluene removal efficiency and 97.28% CO2 selectivity at 200 °C, as well as satisfactory stability and moisture resistance. Therefore, Cu1Ce3 catalyst indicates a huge potential for practical applications, such as coal-fired flue gas and spray coating industry. The reaction pathways for toluene catalytic oxidation over the Cu1Ce3 catalyst were further illuminated by in-situ DRIFTs. In the main pathway, toluene molecules were firstly in contact with the interface lattice oxygen, then the abstraction of H atoms occurred on the methyl group, and benzyl alcohol is considered as the primary intermediate, during which the rate-determining step is the oxidation of benzyl alcohol. In the secondary pathway, a little proportion of toluene molecules were directly oxidized into benzoic acid by the chemisorbed oxygen species. In subsequent steps, all the intermediates were converted into CO2 and H2O. At last, it is confirmed that the toluene oxidation over Cu1Ce3 catalyst involves a Mars-van-Krevelen mechanism via this study.

Compression and liquefaction of carbon dioxide are important parts of the carbon capture, utilization, and storage (CCUS) process. A CCUS project with an actual workload of 1 million tons/year of China is simulated and analyzed in this paper. A new process scheme of compressed liquefaction of CO2 in the CCUS project by using liquid natural gas (LNG) cold energy through CO2 pipeline transportation is proposed to save energy and reduce consumption. The CO2 hydrate prediction models were compared. Based on the thermodynamic path of the CO2 compression liquefaction process, the energy consumption of four process models is compared. The relevant factors, which affect the economy of the new process are investigated, and the technical and economic model is optimized for the new technology scheme of CO2 pipeline. The total cost of the new process of economic is evaluated and the effective quantitative distances for energy saving are obtained. The results show that when the moisture content of CO2 is below 500ppmMol, the new technology will not cause hydrate blockage. The economic viability of the new process (Three stage compression with compressor + liquefaction by using cold energy + pump) is significantly affected by the distance between the LNG receiving station and thermal power plant, and the total cost will be reduced by 30%, 23% , and 8% at a distance of 25, 50 and 100 km, respectively. The distance between LNG receiving station and gas power plant is 125 km, the application of new technology can bring about energy saving and consumption reduction. Through the sensitivity analysis based on NPV and IRR of the new process, the results are economically feasible, and CO2 profit is the most sensitive factor.

Heavy oil have attracted more and more attention. Experimental results show that the high viscosity gas-liquid two-phase flow behaviors are very different from the low viscosity. In this paper, experiments of oil-gas two-phase flow in vertical pipes with different viscosities (50,150,200 mPa s) were carried out in a diameter of 60 mm. The variation of flow pattern, liquid holdup and pressure drop with viscosity was analyzed, the transition flow (from slug to churn flow) was observed. Two empirical models and three mechanistic models were validated by experimental data, the performance of all five models become worse with the increase of viscosity and the performance of mechanistic models are better than that of empirical models. Future experimental and theoretical studies should focus on improve the accuracy of the closure relationships for high viscosity.

It is necessary to control the emissions of toluene, which is hazardous to both human health and the atmosphere environment and has been classified as a priority pollutant. Manganese oxide-based (Mn-based) catalysts have received increased attention due to their high catalytic performance, good physicochemical characteristic, availability in various crystal structures and morphologies, and being environmentally friendly and low cost. These catalysts can be classified into five categories, namely single manganese oxide, Mn-based composite oxides, Mn-based special oxides, supported Mn-based oxides, and Mn-based monoliths. This review focused on the recent progress on the five types of Mn-based catalysts for catalytic removal of toluene at low temperature and further systematically summarized the strategies improving catalysts, including improving synthetic methods, incorporating MnOx with other metal oxides, depositing Mn-based oxides on proper supports, and tuning the supports. Moreover, the effect of coexisting components, the reaction kinetics, and the oxidation mechanisms toward the removal of toluene were also discussed. Finally, the future research direction of this field was presented.

With the 9-phenyl-9-phosphafluorene oxide (PhFlOP) moiety as the acceptor (A) and various donors (D), a series of new organic emitters have been synthesized with a D-A-D configuration. Their photophysical and electrochemical behaviors and electroluminescent (EL) performances have been characterized in detail. The photophysical results have indicated that the PhFlOP-based emitters with acridyl, phenoxazyl, and phenothiazyl as donors show efficient, thermally activated delayed fluorescence (TADF) behavior, especially for the TADF emitter with the phenoxazyl donor possessing an exceptionally high rate constant of reverse intersystem crossing (

Impregnating CuCl

A series of polymeric hosts with cardo-type backbone have been successfully developed with cheap palladium-free catalyst through controlling the special orientation of different monomers. By engineering the configuration of polymer backbones with different number and kind of the functional groups attached to the monomers, the triplet energy-levels (ETs) of these new polymeric hosts can be precisely controlled from 1.92 to 2.83 eV. Importantly, the functional groups on the monomers can afford improved and balanced charge carrier injection/transporting ability to these polymeric hosts. In addition, these polymeric hosts can show good thermal property with decomposition temperatures (Td) higher 410 °C and glass transition temperatures (Tg) higher than 170 °C. Benefitting from all these advanced properties, solution-processed phosphorescent organic light-emitting devices (PhOLEDs) based on these polymeric hosts can show impressive electroluminescence (EL) performances. The optimized blue device B2 possesses a maximum luminance efficiency (ηL) of 25.5 cd A−1, corresponding to a power efficiency (ηP) of 19.9 lm W−1 and an external quantum efficiency (ηext) of 11.3%. The maximum ηL, ηP and ηext for the optimized green device G2 are 66.9 cd A−1, 62.8 lm W−1 and 19.5%, respectively, while EL efficiencies of the optimized red device R2 can reach 11.0 cd A−1, 9.4 lm W−1 and 15.5%. All of the promising EL data achieved by these polymeric hosts show their great potential application in developing high performance polymer-based OLEDs.

The influences of SO2 on Hg° removal over the 1V-8Ce/AC sorbent were systematically investigated at low temperatures. The experimental results showed that SO2 has a dual effect on Hg° removal, that is, SO2 has both a promoting effect and an inhibiting effect on Hg° removal. The SO2 transient response experiment indicated that SO2 could not only react with Hg° to promote the removal of Hg° but also react with the active components and poison the sorbent. O2 is indispensable for the removal of Hg°, which can offset the adverse effects caused by SO2 and H2O. HCl exhibited an obvious promoting effect on Hg° removal in the presence of SO2. The 1V-8Ce/AC sorbent exhibited good sulfur resistance and excellent stability (EHg = 90.04 %) after a 24 h reaction performed under the 1000 ppm SO2 condition at 150 °C. In addition, the Hg-TPD and XPS methods were used to assist in studying the effect of SO2 on Hg° removal over the 1V-8Ce/AC sorbent. Finally, the mechanism of Hg° removal in an SO2 atmosphere was also explored, which showed that Hg° was removed by two possible pathways over the 1V-8Ce/AC sorbent.

In situ catalytic conversion of biomass fast pyrolysis vapors was carried out on HZSM-5 with varying Si/Al ratios (ranging from 20 to 300) at 450 °C. The effects of Si/Al ratios of HZSM-5 zeolites on the distribution of biomass fast pyrolysis products and carbon deposits on catalysts were investigated. It was quite remarkable that after in situ catalytic conversion the amount of light phenols and hydrocarbons increased significantly while that of heavy phenols decreased a lot. Besides, the yield of cyclopentenones with relatively low oxygen content generally increased. It also indicated that as the Si/Al ratios of HZSM-5 increased, the amount of hydrocarbons and light phenols was found to drop greatly. The amount of carbon deposits was found to be around 8.5% with the exception of HZSM-5 with the Si/Al ratio of 300, which is much lower. Moreover, the carbon deposits yield dropped gradually with increasing Si/Al ratios of HZSM-5.Calcination of spent catalysts at 600 °C helped to restore the catalytic activity to a large extent despite a relatively lower efficiency of deoxygenation. Results indicated that HZSM-5 with relatively high acidity displayed great catalytic performance.

A series of bimetallic oxides of manganese and copper with different loading of copper loaded on activated coke (MnxCuy/AC) were synthesized by ultrasound-assisted equivalent volume impregnation method for toluene oxidation in simulated flue gas at 150–300 °C. The physicochemical properties of samples have been investigated by means of XRD, SEM, BET, XPS, H2-TPR and DRIFT. Mn6Cu5/AC exhibited the enhanced toluene removal efficiency (99.38%) at 270 °C, as well as satisfactory reusability and durability. The excellent activity of Mn6Cu5/AC was connected with the highly uniform distribution of active components and the larger specific surface area, which confirmed the synergistic interaction between MnOx and CuOx, thus leading to the stronger reducibility and the good oxygen mobility. In addition, SO2 and NO played a hindering role due to the competitive adsorption of active sites in pure N2, whereas the negative effect would be reduced by the introduction of O2. Besides, the influence of H2O on toluene removal was complex. Moreover, the reaction process obtained from DRIFT indicated that toluene can be rapidly adsorbed and activated to form the benzaldehyde and maleic anhydride species on Mn6Cu5/AC, and finally be further oxidized into CO2 and H2O. Finally, the mechanism of toluene oxidation over Mn6Cu5/AC was proposed.

For the envisaged large number of commercial-scale carbon capture and storage (CCS) projects that are to be implemented in the near future, a number of issues still need to be resolved, the most prominent being the large capital and operational costs incurred for the CO2 capture and compression process. An economic assessment of the capture and compression system based on optimal design data is important for CCS deployment. In this paper, the parametric process design approach is used to optimally design coal and natural gas monoethanolamine (MEA)-based post-combustion CO2 absorption&ndash, desorption capture (PCC) and compression plants that can be integrated into large-scale 550 MW coal-fired and 555 MW natural gas combined cycle (NGCC) power plants, respectively, for capturing CO2 from their flue gases. The study then comparatively assesses the energy performance and economic viabilities of both plants to ascertain their operational feasibilities and relative costs. The parametric processes are presented and discussed. The results indicate that, at 90% CO2 capture efficiency, for the coal PCC plant, with 13.5 mol.% CO2 in the inlet flue gas, at an optimum liquid/gas ratio of 2.87 kg/kg and CO2 lean loading of 0.2082 mol CO2/mol MEA, the CO2 avoidance cost is about $72/tCO2, and, for the NGCC PCC plant, with 4.04 mol.% CO2 in the inlet flue gas, at an optimum liquid/gas ratio of 0.98 kg/kg and CO2 lean loading of 0.2307 mol CO2/mol MEA, the CO2 avoidance cost is about $94/tCO2.

MnO2-Ac, MnO2-N, MnO2-Cl and MnO2-S samples were prepared by the redox reaction between potassium permanganate and manganese acetate, manganese nitrate, manganese chloride and manganese sulfate and the effect of Mn (II) precursor on the toluene oxidation was studied. The physicochemical properties of these samples were characterized by XRD, TEM, N2 asdorption-desorption isotherms, H2-TPR and XPS. Results showed that the catalytic activity of the four samples decreased in the order of MnO2-Ac > MnO2-N > MnO2-Cl > MnO2-S, which was highly related to the specific surface areas, oxygen vacancy concentration and the content of adsorbed oxygen. MnO2-Ac owned potential for practical applications. It showed superior toluene oxidation activity with T90 of 200 °C, as well as excellent water-resistance and stability during 50 h at 300 °C. The good catalytic activities under high WHSV and high toluene concentration were also observed over MnO2-Ac. Moreover, the reaction pathway of toluene oxidation was presented with the aid of In-situ DRIFTS.

Kimura disease (KD) is a rare chronic granulomatous inflammation disease with unknown causes, which is common in young Asian males. Local lymph node drainages are characteristic of the disease, the most common of which occur in the salivary glands. Other reported drainages occur in the axilla, popliteal fossa, groin, and upper extremities. Unfortunately, there not many characteristic manifestations that typically present in patients with KD. Sometimes only increased peripheral blood eosinophils and serum IgE concentration are the only positive presentations. Therefore, it is very difficult for physicians to diagnose KD. We report herein on two cases of KD. Both of them presented in the soft tissues of the upper extremities. Special attention was given to the MRI findings of the two patients with a view to disclosing specific characteristics that should help in the realization of clinical diagnosis.

The density and refractive index were determined for four binary mixtures of 1,3,5-trimethyl-1,3,5-tris(3,3,3-trifluoropropyl) cyclotrisiloxane with octamethyl-cyclotetrasiloxane, hexamethyldisiloxane, 2,4,6,8-tetramethyl-cyclotetrasiloxane and 2,4,6,8-tetramethyl-2,4,6,8-tetraethenylcyclotetrasiloxane at different temperatures T = (308.15, 313.15, 318.15, 323.15 and 328.15) K and atmospheric pressure using a DMA4500/RXA170 combined system. The excess molar volume, partial excess volume at infinite dilution, isobaric coefficient of thermal expansion, excess refraction indices, Lorentz–Lorenz molar refraction and the deviation in molar refraction have been calculated using this data. The results have been incorporated into the Redlich–Kister equation and used to estimate the binary interaction parameters and standard deviation. The values of partial excess volume at infinite dilution and excess refraction indices for the four binary systems at different temperatures were calculated using the adjustable parameters of the Redlich–Kister smoothing equation. The factors that affect these excess quantities are discussed.

The density and refractive index were determined for binary mixtures of triethoxysilane, methyltriethoxysilane, vinyltriethoxysilane and 3-mercaptopropyltriethoxysilane with ethylbenzene at different temperatures (T = 288.15, 298.15, 308.15, 318.15 and 328.15 K) and atmospheric pressure using a DMA4500R1 i ), isobaric coefficient of thermal expansion (a), excess squared refraction indices [(n 2 ) E ], Lorentz–Lorenz molar refraction (Rm) and the deviation in molar refraction (DRm) have been calculated using this data. The results have been incorporated into the Redlich–Kister equation and used to estimate the binary interaction parameter and standard deviation. In addition, the excess molar volume (V E m) was calculated and correlated using the Legendre polynomials. The value of partial excess volume at infinite dilution ( V E;1 i ) for these binary systems at different temperatures was calculated from either the adjustable parameters of Redlich–Kister smoothing equation or the Legendre polynomials. The isobaric coefficient of thermal expansion (a) of the binary systems was estimated using the temperature dependence of the densities. The results indicate that the excess molar volumes, excess squared refraction indices and the deviations in molar refractions at each temperature were negative. These phenomena are a result of a number of factors including: the partial interstitial accommodation effect, disruption in the orientational order of the pure components and steric structure.

Density and refractive index were measured for the binary mixtures composed of 1,3-Diethenyl-1,1,3,3-tetramethyldisiloxane and aromatic hydrocarbons (methoxybenzene, ethylbenzene, chlorobenzene, fluorobenzene and nitrobenzene) at five temperatures (283.15, 288.15, 293.15, 298.15, and 303.15) K and atmospheric pressure by a DMA4500&RXA170 combined system. Excess molar volumes were calculated and correlated by the Legendre polynomials. The isobaric coefficients of thermal expansion and excess isobaric coefficients of thermal expansion of five binary solutions were estimated from temperature dependence of densities. Values of partial excess volumes at infinite dilution and excess refraction indices for these five binary systems at different temperature were calculated from the adjustable parameters of the Legendre polynomials. The molar refractions were calculated from the Lorentz–Lorenz equation. Factors affected these excess quantities were discussed.

Low-cost solution-processable inverted perovskite solar cells (PSCs) demonstrate great potential toward future photovoltaic market. Unfortunately, general hole transport materials (HTMs) within inverted structure make the performance and stability far uncompetitive compared to the normal structure. Interrogating the fundamentals of these materials, moderate charge carrier mobility and susceptible environmental stability of the undoped molecules are the main causes. Herein, a twisted molecule XY1 is developed as a potential robust dopant-free HTM for inverted PSCs. Compared with traditional poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS), XY1 exhibits much higher hole transport ability and peculiar ultraviolet absorption. Hysteresis-free inverted PSCs based on XY1 exhibits the power conversion efficiency (PCE) of 18.78%, which is among the highest values for inverted PSCs based on dopant-free HTMs. After light soaking for 200 h, the original PCE of XY1-based device is still maintained at the 95% level, indicating the substantially improved operational stability. Besides, large-area (1.00 cm2) inverted PSC based on XY1 shows a competitive PCE of 17.82%.

Soot formation was investigated numerically with CO2 addition in a jet-stirred/plug-flow reactor (JSR/PFR) C2H4/O2/N2 reactor (C/O ratio of 2.2) at atmospheric pressure. An updated Kazakov mechanism emphasizes the effect of the O2/CO2 atmosphere instead of an O2/N2 one in the premixed flame. The soot formation was taken into account in the JSR/PFR for C2H4/O2/N2. The effects of CO2 addition on soot formation in different C2H4/O2/CO2/N2 atmospheres were studied, with special emphasis on the chemical effect. The simulation shows that the endothermic reaction CO2 + HCO + OH is responsible of the reduction of hydrocarbon intermediates in the CO2 added combustion through the supplementary formation of hydroxyl radicals. The competition of CO2 for H radical through the above forward reaction with the single most important chain branching reaction H + O2O + OH reduces significantly the fuel burning rate. The chemical effects of CO2 cause a significant increase in residence time and mole fractions of CO and OH, significant decreases in some intermediates (H, C2H2), polycyclic aromatic hydrocarbons (PAHs, C6H6 and C16H10, etc.) and soot volume fraction. The CO2 addition will leads to a decrease by only about 5% to 20% of the maximum mole fractions of some C3 to C10 hydrocarbon intermediates. The sensitivity analysis and reaction-path analysis results show that C2H4 reaction path and products are altered due to the CO2 addition.

Density and refractive index were determined for the binary mixtures containing 2,4,6,8-tetramethyl-2,4,6,8-tetraethenylcyclotetrasiloxane ( D 4 Vi ) and aromatic hydrocarbons (ethylbenzene, o -xylene, m -xylene, and p -xylene) at five temperatures (288.15, 298.15, 308.15, 318.15, and 328.15) K and atmospheric pressure by a DMA4500&RXA170 combined system. The density and refractive index correlations for these systems were tested by an empirical second order polynomial and by the Lorentz–Lorenz equation. Excess molar volumes were calculated and correlated by the Redlich–Kister equation and the Legendre polynomials. The values of the volume expansivity (coefficient of thermal expansion) of pure chemicals and four binary solutions were estimated from temperature dependence of densities. Values of partial excess volumes at infinite dilution for these four binary systems at different temperatures were calculated either from the adjustable parameters of Redlich–Kister smoothing equation or the Legendre polynomials. The deviations in refractive index were calculated and correlated by the Redlich–Kister polynomial expansions. The molar refractions were calculated from the Lorentz–Lorenz equation. The deviations in molar refractions were calculated and correlated by the Redlich–Kister polynomial expansions. Factors affected these excess quantities were discussed. The results obtained indicate that the excess molar volumes, the deviations in refractive index and the deviations in molar reactions at each temperature are negative. The system { D 4 Vi ( 1 ) + o -xylene ( 2 ) } exhibits the maximum negative deviations from ideality among these four systems, which is the result of multiple factors such as the partial interstitial accommodation effect, the steric hindrance, the size of molecule and the instantaneous dipole-induced dipole interactions.

Vapor pressures, vaporization enthalpies and acentric factors for new compounds, diethoxy(methyl)(o-tolyl)silane, diethoxy(methyl)(m-tolyl)silane and diethoxy(methyl)(p-tolyl)silane were reported. The saturated temperature was measured using the inclined ebulliometer in the pressure range from 2000 to 61,000 Pa and the normal boiling point was measured according to the Siwoloboff method. The standard vaporization enthalpy was derived from the temperature dependence of vapor pressure data. The critical parameters were estimated by an improved group contribution method and the acentric factors have been estimated from the Antoine equation and the experimental normal boiling points.

In this paper, by using the center manifold reduction method, together with the eigenvalue analysis, we made bifurcation analysis for the Kuramoto–Sivashinsky equation, and proved that the Kuramoto–Sivashinsky equation with constraint condition bifurcates an attractor A λ as λ crossed the first critical value λ 0 = 1 under the two cases. Our analysis was based on a new and mature attractor bifurcation theory developed by Ma and Wang (2005) [17] , [18] .

In this paper, by using an iteration procedure, regularity estimates for the linear semigroups and a classical existence theorem of global attractor, we prove that a modified Swift–Hohenberg equation u t = − Δ 2 u + g ( u ) possesses a global attractor in Sobolev space H k for all k ≥ 0 , which attracts any bounded subset of H k ( Ω ) in the H k -norm.

In this paper we prove that the initial-boundary value problem for the nonlinear evolution equation u t =Δ u + Λ u − u 3 possesses a global attractor in Sobolev space H k for all k ≥ 0, which attracts any bounded domain of H k (Ω) in the H k -norm. This result is established by using an iteration technique and regularity estimates for linear semigroup of operator, which extends the classical result from the case k ∈ [0, 1] to the case k ∈ [0, ∞).

In this paper, by using an iteration procedure, regularity estimates for the linear semigroups and a classical existence theorem of global attractor we prove that the Cahn–Hilliard equation u t = − Δ 2 u + Δ g ( u ) possesses a global attractor in Sobolev space H k for all k ⩾ 0 , which attracts any bounded subset of H k ( Ω ) in the H k -norm.

A rapid, sensitive and specific method based on high performance liquid chromatography-electrospray ionization-mass spectrometry was developed for the determination of tiopronin in human plasma. In this study, vitamin C and dithiothreitol were used as the reducer and to release and stabilize tiopronin from dimeric mixed forms with endogenous thiols encountered during pretreatment of plasma samples. The separation was successfully achieved on an Agilent SB-Aq column packed with 5 μm C18 silica, using an aqueous formic acid solution (pH 4.5–4.7), 0.5 mM tris(hydroxymethyl)aminomethane and methanol (95:5, v/v) as the mobile phase. Mass spectra were acquired in selective ion monitoring mode, using the [M − H] − ions of tiopronin at m/z 162.0 and the [M − H]− of the internal standard sodium cyclamate at m/z 178.0, respectively. This quantitative assay was fully validated with respect to precision, repeatability and accuracy. The correlation coefficients were >0.9995 in the range 0.025–8.15 μg mL−1 in human plasma. The mean recoveries were above 85%. The limit of quantitation was 0.012 μg mL−1 with a relative standard deviation of inter-day and intra-day accuracy of less than 15%. This LC-ESI-MS method was also successfully applied to a pharmacokinetic study after oral administration of formulated tiopronin to healthy volunteers. The elimination half-life (T 1/2) was 21.5 ± 11.1 h.

In this paper, we use the iteration technique for regularity estimates, combining with the classical existence theorem of global attractors, to derive that for any k ≥ 0 the semilinear parabolic equation possesses a global attractor in H k ( Ω ) , which attracts any bounded subset of H k ( Ω ) in the H k -norm.

To examine the proportion and reasons of drop-out from antiretroviral therapy (ART) among 8 367 adult HIV-infected individuals in Dehong prefecture, Yunnan province.All adult HIV-infected patients receiving ART before September 30 of 2014 were examined for the situation of drop-out from ART.The proportion of drop-out from ART among adult HIV-infected patients in Dehong prefecture was 14.4% (1 202/8 367). Results from the univariate logistic regression analyses indicated that drop-out from ART was significantly correlated with factors as: living area, gender, age, marital status, HIV transmission route, baseline CD4⁺ T cell counts and initial treatment regimen of the patients. After adjusted for potential confounding variables by multiple logistic regression model, drop-out from ART was significantly correlated with residential area, marital status, HIV transmission route, baseline CD4⁺ T cell count and initial treatment regimen of the patients. HIV-infected patients who were living in Mangshi city, Lianghe county or Yingjiang County, being married or living with partner, HIV infection through sexual contact, with baseline CD4⁺ T cell counts ≤ 200 cells/mm³, and ART included in the initial treatment regimen etc., were less likely to drop out from ART. The proportion of drop out from ART was significantly decreasing along with the increasing time of ART. Data from specific investigation revealed that among the 1 202 patients who dropped out from ART, 704 (58.6%) were lost to follow-up, 303 (25.2%) did not adhere to treatment, 74 (6.2%) moved out the region, 64 (5.3%) were Burmese that had returned to Burma, 29 (2.4%) stopped the treatment according to doctors' advice, 18 (1.5%) were incarcerated and 10 (0.8%) were under other reasons. Reasons for the drop-out varied, according to the situation of patients.The proportion of drop-out from ART varied significantly according to the characteristics of HIV-infected patients in Dehong prefecture that underscoring the needs for tailored responses to reduce drop-out of ART. Focus should be targeted on reducing the loss to follow-up and improving the treatment adherence.

To understand HIV rival suppression and drug resistance (HIVDR) among AIDS patients who were receiving antiretroviral treatment (ART) in Dehong prefecture, Yunnan province.All AIDS patients who were aged over 15 years and with experience more than six months on ART by the end of 2012 in Dehong prefecture, were enrolled to receive testing for HIV viral load in plasma and genetic mutations associated with HIVDR.A total of 4 390 AIDS patients were qualified for the study according to the selection criteria, of whom 3 964 (90.3%) finally participated in the study. Among them, 2 307(58.2%) had CD₄(+) cell counts more than 350 cells/mm³. 3 169 (79.9%) patients showed undetectable plasma HIV viral load which was lower than the detection threshold. Those who had the following factors as:resided in Ruili city, being female, older than 45 years of age, married, heterosexually infected with HIV, having received ART more than 5 years, and CD₄(+) cell counts500 cells/mm³, were more likely to have undetectable plasma virus load, with the differences statistically significant. 402 (10.1%) patients had plasma viral load ≥ 1 000 copies/ml, of whom 353 (87.8%) were successfully amplified and examined for HIVDR. Among them, 198 (56.1% ) were identified to bear genetic mutations associated with HIVDR. Most mutations were related to the resistance to nucleotide reverse transcriptase inhibitors (NNRTIs) or non-nucleotide reverse transcriptase inhibitors (NNRTIs), with M184V and K103N most frequently seen. 12 patients (3.4%) were found to have mutations resistant to protease inhibitors (PI). Data from multiple logistic regression analysis indicated that the period of receiving ART and the initial ART regimen could both significantly predict the occurrence of HIV resistance.Viral suppression was highly achieved among ART-prescribed AIDS patients in Dehong prefecture,Yunnan province. However, among those who did not show effective viral suppression, the proportion of HIVDR was high, underscoring the needs for health education so as to improve the adherence to drugs as well as for improving testing for viral load and HIVDR among AIDS patients.