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Background: Stroke has become one of the diseases with the highest mortality and disability rates in the world, especially in low-income and developing countries. Our objective was to discuss the relationship between the longitudinal dynamic changes of triglyceride and stroke onset in healthy populations by constructing different parametric joint models. Methods: 298 participants aged 23 to 69 in Xijing hospital of Xi’an City in Shanxi Province from 2008 to 2015 were included. The Cox proportional hazards model was performed to analyze the correlation between triglyceride and stroke incidence at baseline. Different parameterized joint models were used to analyze the impact of dynamic changes of triglyceride on the incidence of stroke under longitudinal data. Results: Of the 298 participants, a total of 70 (23.49%) subjects developed stroke during the study period. Cox proportional hazards model showed that the risk of disease increased by 1.056 times (95%CI=0.920-0.975) for each 1 unit of baseline age decrease. Each 1 mmol/L increase in sqrt(triglyceride) increased the risk by 1.816 times (95%CI=1.017-3.245). Joint model showed that the risk of sqrt(triglyceride) increased by 4.869 times (95%CI=3.987-8.857) for each 1 mmol/L increase in the longitudinal direction. The lagged effects (HR=5.284, 95%CI=4.397-9.680) and cumulative effects (HR=1.786, 95%CI=1.613-3.399) of sqrt(triglyceride) dynamic trajectory were also statistically related to the incidence of stroke. Conclusions: Over time, the longitudinal growth of triglyceride levels in individuals will increase the risk of stroke even more. People should pay more attention to the dynamic changes of individual triglyceride values, as well as the lagged effect and cumulative effect, to reduce the incidence of stroke.

Active chlorine decontaminants like hypochlorite are used to destroy chemical warfare agents (CWAs) such as HD, VX and GD due to the former's strong oxidation capacity and high nucleophilicity. In this paper, experiments were performed to identify the main factors affecting agent recovery from decon water. Based on the results, a method to recover residual CWAs from hypochlorite decon water before quantitative determination by GC was developed. The results showed that the extraction solvent was a critical determinant of high CWA recovery. Dichloromethane was more suitable than petroleum either, especially for samples containing GD or low residual CWAs. For VX-containing samples, the use of an alkali solution improved VX recovery. Neutralization was also important for a high CWA recovery, especially for samples with low CWA concentrations and/or strong decontaminant reactivity. The use of 15% sodium sulfite as the neutralization solution gave the best results for hypochlorite decon water. When the optimized conditions of simultaneous sodium sulfite neutralization and dichloromethane extraction were used, the recovery of HD, VX and GD in hypochlorite decon water was greater than 85% at a concentration range of 20 mg/L to 10,000 mg/L.

Chloramine-T, especially its solution in weak acidity, is one of the decontaminants for chemical warfare agents (CWAs), HD, and VX. A high CWAs recovery from decontamination (decon) sample via pretreatment was essential for evaluating decontamination effects. This paper performed experiments to optimize pretreatment methods to extract residual CWAs from chloramine-T decon samples before GC analysis. Effects of two neutralization methods, destroying decon activity by 15% Na

Background: Stroke has become one of the diseases with the highest mortality and disability rates in the world, especially in low-income and developing countries. Our objective was to discuss the relationship between the longitudinal dynamic changes of TG and stroke onset in healthy population by constructing different parametric joint models.Methods: 298 participants aged 23 to 69 in Xijing hospital of Xi’an City in Shanxi Province from 2008 to 2015 were included. The Cox proportional hazards model was performed to analyze the correlation between TG and stroke incidence at baseline. Different parameterized joint models were used to analyze the impact of dynamic changes of TG on the incidence of stroke under longitudinal data.Results: Of the 298 participants, a total of 70 (23.49%) subjects developed stroke during the study period. Cox proportional hazards model showed that the risk of disease increased by 1.056 times (95%CI=0.920-0.975) for each 1 unit of baseline age decrease. Each 1 mmol/L increase in sqrt(TG) increased the risk by 1.816 times (95%CI=1.017-3.245). Joint model showed that the risk of sqrt (TG) increased by 4.869 times (95%CI=3.987-8.857) for each 1 mmol/L increase in longitudinal direction.The lagged effects (HR=5.284, 95%CI=4.397-9.680) and cumulative effects (HR=1.786, 95%CI=1.613-3.399) of sqrt (TG) dynamic trajectory were also statistically related to the incidence of stroke.Conclusions: Over time, the longitudinal growth of TG levels in individuals will increase the risk of stroke even more. People should pay more attention to the dynamic changes of individual TG value, as well as the lagged effect and cumulative effect, to reduce the incidence of stroke.

Chlorine-based decontaminant BX24 is effective for the decontamination of chemical warfare agents (CWAs) VX, GD and HD. In this paper, main factors affecting the agent recovery from decontamination water (decon water) were studied, a pretreatment method was subsequently developed for GC analysis of residual chemical warfare agents in BX24 decon water. Results showed that dichloromethane was the most suitable extractant, especially for sample of VX and GD. Neutralization process should be done to obtain a high recovery, especially for samples under low CWAs concentration and samples with high speed of CWAs degradation like HD decon water. When optimized neutralizer of sodium sulfite or sodium thiosulfate and extractant of dichloromethane were used, where neutralization and extraction were done simultaneously, a recovery above 85% could be obtained for BX24 decon water. The appropriate CWAs concentration ranged from 20 mg/l to 10000 mg/l.

Fluoride ion-selective electrode was widely used in trace F- test of food, medicinal materials and various water sources, etc.. It could also be used to monitor the concentration change of F- produced by GB and GD (G agents) hydrolysis. In this paper, two sorts of peroxide solutions, 1% sodium percarbonate (SPC) and 1 % sodium percarbonate combined with 0.9 % acetylsalicylic acid solution (SPC-Aspirin), worked as decontamination solutions (decon solutions). In view of the effect of ionic strength of decon solution on F- activity, calibration for linear correlation between the concentrations of standard F- aqueous in decon solutions and its related values showeded on the meter with a fluoride ion-selective electrode was firstly done, kinetic experiments of GB and GD hydrolysis were carried subsequently. Results showed that the components of HOO- in SPC and CH3COOO- in SPC-Aspirin played the major role in catalyzing G agents hydrolysis. The stronger nucleophilicity of decon solution was, the faster G agents hydrolyzed. The first order rate constants of GB and GD hydrolysis in SPC-Aspirin solution were 6.8×10-2 s-1 and 5.8×10-2 s-1, respectively, both above 10 times greater than that in SPC solution. Consequently, the nucleophilicity of CH3COOO- was stronger than HOO-. Due to relatively higher stereo-hindrance effect of GD with pinacolyl group, GD hydrolyzed more slowly than GB.

Organophosphate neurotoxic agents like Sarin (GB) and Soman (GD) are lethal to person. Except various kinds of decontaminants, they can be also decomposed in natural environment through nucleophilic reaction, where acidic or alkaline substance was to accelerate their hydrolysis. Most of the papers were about GB hydrolysis. Information on GD hydrolysis was relatively small, especially about kinetics of GD in acidic solution. In view of possible effect of positive ion and negative ion on hydrolysis reaction, a relatively simple composes solution, HCl aqueous solutions, was selected to investigate the factors affecting GD hydrolysis rate. Results showed that GD hydrolysis was accorded with the first-order kinetics equation if pH value was kept constant. Its rate constant was independent of GD initial concentration when the amount of H+ was excess than its requested amount. The apparent hydrolysis rate constant (kobs) in pH of 0.90 was about 0.202 min-1 at 20°C, no matter what initial concentration of GD was. The concentration of H+ was the most important factor affecting its rate. The rate constant (kobs) in HCl aqueous as a function of pH value (0.90~2.80) obeyed an equation in 25°C, that is kobs =0.17×10-0.82×pH. Reaction temperature had an obvious effect on hydrolysis rate of GD. Every 10°C increase in temperature, kobs of GD hydrolysis was improved about 2.5 times. The activation energy value (Ea) of GD hydrolysis in HCl aqueous with a pH value of 0.90 was approximately 64.25 kJ/mol.

The decontaminant activated by MoO42- (MoO42--H2O2) suitable for subzero environment shows strong oxidizing ability and weak nucleophilicity due to its acid. In this paper, in order to improve nucleophilicity and retain oxidation of MoO42--H2O2 as far as possible, NH3 and NaOH were used as alkaline modifiers, and PhSMe was used as a simulant of HD to study the oxidation rate and products of sulfides by alkaline-modified MoO42--H2O2 below zero. Results showed that the reaction rate constants decreased with the increase of pH in both NH3 and NaOH modified MoO42--H2O2 at -20°C, and the relative ratio of sulfone to sulfoxide increased especially at pH>9. The reaction activation energy Ea of PhSMe oxidation in the alkaline-modified MoO42--H2O2 decontaminants was lower than that in the MoO42--H2O2 decontaminant, which indicated that the sensitivity of the oxidation reaction rate to temperature in MoO42--H2O2 was reduced after modification.

Sarin (GB) and soman (GD) are severely toxic nerve agents that react slowly in water, resulting in long-term poisoning of the water and a serious threat to personnel. Some ions can catalyse GB and GD hydrolysis in water; the relevant research for GB is detailed, whereas that for GD is relatively less so. In this paper, GD hydrolysis catalysed by hypochlorite (ClO−) ions was studied via kinetic experiments. A fluorite-ion-specific electrode was used to monitor F− ions produced, allowing the rate constant and half-life of the GD hydrolysis to be calculated. The results showed that ClO− ions promote GD hydrolysis well; the higher the concentration of ClO−, the faster the GD was hydrolysed. In NaClO solution at pH 8.0 with 3.22×10–3 M ClO− ions, the half-life of GD hydrolysis was 82.5 s, about 875 times shorter than that in water at pH 8.0. The rate constant for catalysis of GD hydrolysis by ClO- ions ++(kc1o−)++ was 2.6 M−1 s−1, about one quarter the value of ++koh− ++but over 1500 times greater than kB and ++kPO4,++ with B representing N-2-hydroxyethylpiperazine-N’-2-ethanesulfonic acid present as a free base; this result indicated that ClO− ions catalyse GD hydrolysis well.

Peroxides like sodium percarbonate (SPC) and sodium percarbonate-acetylsalicylic acid (SPC-Aspirin) can be used to destroy chemical warfare agents (CWAs) such as HD, VX and GD due to the former's oxidation capacity and nucleophilicity. In this paper, experiments were performed to study factors affecting CWAs recovery from peroxides decontaminant water (decon water) and develop the method to recover residual CWAs from peroxides decon water before GC analysis. Results showed that extraction solvent and neutralization were important for high CWA recovery. DCM was more suitable than PE as extractant for most samples except SPC decon water containing HD. Sodium sulfite could well neutralized decontaminant reactivity in decon water. When suitable conditions of simultaneous neutralization and extraction were carried, CWAs recovery from SPC decon water were greater than 90% at a concentration range of 10 mg l-1 to 10000 mg l-1, the recovery of HD, VX and GD from SPC-Aspirin decon water was more than 90%, 80% and 95% respectively at a concentration range of 100 mg l-1 to 10000 mg l-1, while CWAs recovery were relatively lower from SPC-Aspirin decon water with CWAs concentration of 10 mg l-1 due to the degradation of CWAs during pretreatment processes.

Flower-like porous ZnO was successfully synthesized by a simple hydrothermal method followed by calcination. The morphologies of the as-prepared materials were characterized by scanning electron microscopy (SEM) and the crystal structures were determined by X-ray diffraction. It can be seen in SEM images that each flower-like ZnO unit is composed of randomly arranged ZnO thin flakes which makes the materials extremely porous. Meanwhile, there are numerous through-holes distributed on the surface of ZnO flakes. The gas-sensing properties of the as-prepared materials were investigated, and the results indicate the ultrahigh sensing properties of flower-like porous ZnO to acetone. The response of flower-like porous ZnO sensors to 50 ppm acetone is about 97.8 at the optimum operating temperature of 280 °C. The response and recovery times to 50 ppm acetone are about 2 and 23 s, respectively. Moreover, even at low concentrations of 0.25, 1 and 10 ppm acetone high responses can be observed with the values of 6.7, 15.8 and 30.1. In addition, the as-synthesized flower-like ZnO shows excellent selectivity to acetone and the response to 50 ppm acetone (97.8) is about 4.43 times larger than ethanol (22.1) at the same concentration, which can successfully distinguish acetone and ethanol.

The ruptured Nd-doped In2O3 porous nanotubes have been successfully synthesized by single-capillary electrospinning method. The morphologies of the as-prepared materials were characterized by scanning electron microscopy and transmission electron microscopy. It can be seen obviously that the surface of the nanotubes are distributed with cracks and pores, which formed such an open nanostructure. The crystal structures and components were determined by x-ray diffraction, energy-dispersive x-ray spectroscopy and x-ray photoelectron spectrometer. The gas-sensing properties of ruptured Nd-doped In2O3 porous nanotubes were studied and the results show the excellent performances of the as-obtained materials. The response of ruptured Nd-doped In2O3 porous nanotubes to 100 ppm of formaldehyde is 46.8 at the optimum temperature of 240°C. The response and recovery times are 8 s and 22 s, respectively. Furthermore, the lowest detection limit of formaldehyde is 100 ppb with the value of 2.4. In addition, the ruptured Nd-doped In2O3 porous nanotubes exhibit good selectivity to formaldehyde and long-term stability.

Biomorphic In2O3–ZnO hollow microtubules were synthesized by using cotton as template and followed by calcination. This environmental-friendly method using biomaterials as templates can be used to synthesize metal oxide semiconductor materials with specific morphologies. The structural and microscopy characterization were carried out with X-ray diffraction, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy. The SEM images display the porous structure of the as-obtained hollow microtubules, which is beneficial to increase gas sensing properties of materials. Gas sensors based on In2O3-doped ZnO hollow microtubules were investigated and the test results demonstrate the excellent acetone sensing properties of such porous materials. The response of In2O3–ZnO hollow microtubule sensors to 100 ppm acetone at the optimum temperature of 300 °C is 62.5, meanwhile the response and recovery times are 3 and 7 s, respectively. Moreover, even at 0.1 ppm of acetone detectable response can be observed, and the value is 2.82. At the same time the sensors have selectivity to acetone.

The porous ZnO microflowers, which looks like a flower, has been successfully prepared by a simple hydrothermal method. The structure and morphology of the samples were characterized by X-ray diffraction and Scanning electron microscopy. Meanwhile, the as-prepared samples were applied to fabricate gas sensor device, the gas sensing properties of the sensors based on porous ZnO microflowers were studied. The results indicate the ultrahigh sensitivity and excellent selectivity of Porous ZnO microflowers sensors to ethanol. The response of Porous ZnO microflowers sensor to 100 ppm ethanol is about 123 at 260 °C, which is 4.1 times larger than that of acetone (the response value is 30). The ZnO sensors can successfully distinguish acetone and ethanol which possess similar properties. The results demonstrate that the ZnO sensors have an excellent selectivity to ethanol. The response and recovery time are 4 and 12 s to 50 ppm ethanol, respectively. Moreover, the concentration of ethanol that we can detect is 0.2 ppm, and the response value is 1.65. Thus this work is confirmed that the porous ZnO microflowers sensors have a fantastic gas sensitive property for ethanol.

Pure and Nd-doped porous In 2 O 3 nanotubes have been successfully synthesized by single-capillary electrospinning method. The SEM images displays the novel structure of Nd-doped In 2 O 3 which has pores distributed on the surface of nanotubes. The subsequent test results demonstrate that Nd-doped porous In 2 O 3 nanotubes possess excellent gas-sensing properties to formaldehyde. The response of Nd-doped porous In 2 O 3 nanotubes to 100 ppm formaldehyde is 44.6 at the optimum operating temperature of 240 °C, which is 3.6 times larger than that of pure porous In 2 O 3 nanotubes (12.5), and the response and recovery times to 100 ppm formaldehyde are 15 and 50 s, respectively.

It has been reported a lot that nanowire and nanotube semiconductor oxide type sensor possess excellent sensing property. Many works ascribed excellent sensing properties to the big specific surface area. Herein, In2O3 nanofiber and nanotube were synthesized by single nozzle electrospinning and followed by calcination with different heating rate. And the samples were characterized by scanning electron microscopy, and powder X-ray diffraction. Their gas sensing properties were studied to investigate the advantages of their morphologies, and the response and recovery dynamic curves were also tested to investigate their gas sensitive characteristics. The results show that acetone sensing sensitivity based on nanotubes is better than that of nanowires.

Pure and Er-doped In2O3 nanotubes were systematically fabricated by using a single nozzle eletrospinning method followed by calcination. The as-synthesized nanotubes were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectrometry and X-ray powder diffraction (XRD). Compared with pure In2O3 nanotubes, Er-doped In2O3 nanotubes exhibit improved formaldehyde sensing properties at 260 °C. The response of Er-doped In2O3 nanotubes to 20 ppm formaldehyde is about 12, which is 4 times larger than that of pure In2O3 nanotubes. The response and recovery times of Er-doped In2O3 nanotubes to 20 ppm formaldehyde are about 5 and 38 s, respectively. Furthermore, the response of Er-doped In2O3 nanotubes to 100 ppb formaldehyde is 2.19.

Multiwalled carbon nanotubes (MWNTs) were synthesized through CVD method, and the gas sensitive materials MWNTs/ZnO were obtained by mixing MWNTs and ZnO. The gas sensing properties of the as-prepared materials were investigated. The results show that the gas sensing properties of ZnO sensor are significantly improved by doping MWNTs. The sensitivity, response time and recovery time to 50 ppm ethanol at 260 °C are 46, 4 and 20 s, respectively. We also examined the selectivity of 0.1 wt% MWNTs-doped ZnO sensors to different gases. The results show that the sensor possesses an excellent selectivity to ethanol.

α-Fe2O3 nanotubes was successfully prepared by single nozzle electrospinning method. Scanning electron microscope (SEM) was used to characterize the morphology of α-Fe2O3 nanotubes. The gas sensing properties of α-Fe2O3 nanotubes were investigated in detail. The results exhibit relatively good sensing properties to acetone at 240 °C. The response and recovery times are about 3 and 5 s, respectively. The structure of nanotubes is beneficial to the gas sensing properties, which will enlarge the surface-to-volume ratio of α-Fe2O3 and then be available for the transfer of gas, and thus improved the sensor performance consequentially.

Pure and La-doped (5 wt%, 7 wt% and 10 wt%) α-Fe2O3 nanotubes are synthesized by an electrospinning method and followed by calcination. The as-synthesized nanotubes are characterized by scanning electron microscope (SEM) and X-ray powder diffraction (XRD). Compared with pure α-Fe2O3 nanotubes, La-doped α-Fe2O3 nanotubes exhibit improved acetone sensing properties at 240 °C. The response of 7 wt% La-doped α-Fe2O3 nanotubes to 50 ppm acetone is about 26, which is 10 times larger than that of pure α-Fe2O3 nanotubes. The response and recovery times of 7 wt% La-doped α-Fe2O3 nanotubes to 50 ppm acetone are about 3 and 10 s, respectively. Moreover, 7 wt% La-doped α-Fe2O3 nanotubes show a good selectivity to acetone.

Honeycombed SnO2 is synthesized by a simple wet chemical method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, and N2 adsorption–desorption isotherms. The porous diameter of the honeycombed SnO2 is about 2 μm. Sensing investigation reveals that the obtained SnO2 with a very small BET surface area (19.7 m2 g−1) owns ultra sensitive properties to H2 at 340 °C. The response is 8.4 when the sensors are exposed to 1 ppm H2, and the response and recovery times are 4 and 10 s, respectively. The theoretical model for the infection of porous diameter on the sensing properties is provided.

NiO–SnO2 composite nanofibers are synthesized by electrospinning of a poly(vinyl pyrroridone) (PVP)/SnCl2·2H2O/NiCl2 solution. Indirect-heated sensors are fabricated by coating the nanofibers on ceramic tubes with signal electrodes. The obtained nanofibers are analyzed by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The sensors are tested at different temperatures to various gases. High toluene sensing properties are observed at 330 °C, and the corresponding response value (Ra/Rg), response time, and recovery time are about 11.2 s, and 4 s to 50 ppm toluene at this condition. Good selectivity and excellent stability are also observed based on the sensors at this temperature. These high sensor performances are explained by the sensing enhancement brought about by NiO addition and the one-dimensional nanostructure of nanofibers.

Pure and Co-doped (0.3 wt%, 0.5 wt%, and 1 wt%) ZnO nanofibers are synthesized by an electrospinning method and followed by calcination. The as-synthesized nanofibers are characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray (EDX) spectroscopy. Comparing with pure ZnO nanofibers, Co-doped nanofibers exhibit improved acetone sensing properties at 360 °C. The response of 0.5 wt% Co-doped ZnO nanofibers to 100 ppm acetone is about 16, which is 3.5 times larger than that of pure nanofibers (about 4.4). The response and recovery times of 0.5 wt% Co-doped ZnO nanofibers to 100 ppm acetone are about 6 and 4 s, respectively. Moreover, Co-doped ZnO nanofibers can successfully distinguish acetone and ethanol/methanol, even in a complicated ambience. The high response and quick response/recovery are based on the one-dimensional nanostructure of ZnO nanofibers combining with the Co-doping effect. The selectivity is explained by the different optimized operating temperatures of Co-doped ZnO nanofibers to different gases.

Co–ZnO composite nanofibers (0, 0.2, 0.4, and 0.8 wt%) are synthesized by electrospinning and calcination techniques. The fiber diameters are found to decrease by increasing the Co content in the ZnO nanofibers. The m-xylene sensing properties of the ZnO nanofibers are effectively enhanced with appropriate Co amount. The best sensing properties are found based on the 0.4 wt% Co–ZnO composite nanofibers at 320°C. The corresponding response is up to 14.8 when the sensor is exposed to 100 ppm m-xylene, and the response and recovery times are about 4 and 6 s, respectively. Moreover, excellent selectivity is also observed in the sensing investigation. The results make Co–ZnO composite nanofibers good candidates for fabricating high performance m-xylene sensors.

Pure and NiO–SnO2 nanofibers are synthesized via a simple electrospinning method, and characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The sensor fabricated from 5 mol% NiO–SnO2 nanofibers exhibits improved and excellent sensing properties to ethanol at 300°C. The response is up to 25.5 when the sensor is exposed to 100 ppm ethanol. The response and recovery times are about 2 and 3 s, respectively. The linear dependence of the sensitivity on the ethanol concentration is observed in the range of 5–500 ppm. Good selectivity is also observed in our studies. These results make NiO–SnO2 nanofibers good candidates for fabricating practical ethanol sensors.

SnO2/multiwalled carbon nanotubes (MWNTs) have been studied as gas sensing materials. Compared with pure SnO2, SnO2/MWNTs exhibit improved ethanol sensing properties such as higher sensitivity and quicker response/recovery at 300°C. The sensitivity is 35, 65, 166 and 243 to 500, 1000, 2000 and 3000 ppm ethanol, respectively. The response time is about 1 s, and the recovery time is about 5 s. The sensing improvement is explained in terms of the appropriate basal resistance and enhanced signal transfer brought by MWNTs.

ZnO microcrystals are synthesized through a facile solution method and characterized by field-emission scanning electron microscopy, transmission electron microscopy, selected area electron diffraction and X-ray diffraction. The ethanol sensing properties of these microcrystals are investigated by spin-coating them on a silicon substrate with Pt electrodes to fabricate a micro-structure sensor. The sensitivity is up to 8 when the sensor is exposed to 50 ppm ethanol, and the response time and recovery time are 10 s and 20 s, respectively. A contact-controlled model is established to explain the sensing properties of the microcrystals, which provides another approach to realize high-performance gas sensors.

The catalytic activity of four liquid organic amines, triethylamine (TEA), diethylamine (DEA), ethylenediamine (EDA) and monoethanolamine (MEA), in the transesterification reaction of rapeseed oil in supercritical methanol was studied in this paper. The results showed that the order of the catalytic activity was DEA > TEA > MEA > EDA. The effect of the molar ratio of methanol to oil on the reaction was involved. Further, with TEA as the catalyst, the effect of the reaction pressure on this reaction was investigated. Pressure had a positive effect on this reaction. Additionally, the efficiency of the co-solvent, including ethyl acetate, propylene oxide, tetrahydrofuran and cyclohexanone, was studied, showing that ethyl acetate had a positive effect on this reaction. The overall results suggested that the methyl ester yield in a continuous reactor was inferior to that in a batch reactor, mainly because of the poor mutual solubility between the oil and methanol. Furthermore, possible mechanisms for this amine-catalyzed reaction were proposed.

Normally, the available transfer capability of the study transfer is obtained for a given base power flow. If once the node power changed, the available transfer capability calculation is carried out, a lot times of calculation will be needed, as the commercial software of managing and utilizing system transmission (MUST) does, which will cost a lot of computation time. Based on the processing of the available transfer capability by using distribution factors, the sensitivity of available transfer capability with respect to the node power is proposed. The sensitivity can be used to estimate the available transfer capability of the study transfer and to predict the change region of the available transfer capability when the node power changed. Practical system analysis verified the proposed algorithm.

Transesterification of the crude Jatropha curcas L. oil catalyzed by micro-NaOH in supercritical/subcritical methanol was studied. The effects of various reaction variables such as the catalyst content, reaction temperature, reaction pressure and the molar ratio of methanol to oil on the conversion of crude Jatropha curcas L. oil to biodiesel were investigated. The results showed that even micro-NaOH could noticeably improve this reaction. When NaOH was added from 0.2 to 0.5 to 0.8 wt-%o of triacylglycerols, the transesterification rate increased sharply; when the catalyst content was further increased, the reaction rate was just poorly improved. It was observed that increasing the reaction temperature had a favorable influence on the methyl ester yield. For the molar ratio ranging from 18 to 36, the higher the molar ratio of methanol to oil was charged, the faster the transesterification rate seemed. At the fixed stirring rate of 400 rpm, when the catalyst content, reaction temperature, reaction pressure and the molar ratio of methanol to oil were developed at 0.8 wt-%o NaOH, 523 K, 7.0 MPa and 24 :1, respectively, the methyl ester yield could reach 90.5% within 28 min. Further, the kinetics of this reaction was involved and the results showed that it was a pseudo-first-order reaction whose apparent activation energy was 84.1 kJ/mol, and the pre-exponential factor was 2.21 x 10 5 .

Transesterification reaction of the crude oil of rapeseed with supercritical/subcritical methanol in the presence of a relatively low amount of NaOH was successfully carried out, where soap formation didn't occur. The main factors affecting the methyl ester yield during the transesterification reaction were the catalyst content, the reaction temperature, the molar ratio of alcohol to oil and the water content. High methyl ester yield and fast reaction rate could be obtained even if the reaction pressure was relatively low. In addition, kinetics of the transesterification reaction was also discussed.

Nano-MgO can apparently improve the transesterification reaction of soybean oil with supercritical/subcritical methanol. The variables affecting the yield of methyl ester during the transesterification reaction, such as the catalyst content, reaction temperature and the molar ratio of methanol to soybean oil were investigated and compared with those of non-catalyst. When nano-MgO was added from 0.5 wt% to 3 wt%, the transesterification rate increased evidently, while the catalyst content was further enhanced to 5 wt%, little increased in yield. It was observed that increasing the reaction temperature had a favorable influence on methyl ester yield. In addition, for molar ratios of methanol to soybean oil ranging from 6 to 36, the higher molar ratios of methanol to oil was charged, the faster transesterification rate was obtained. When the temperature was increased to 533 K, the transesterification reaction was essentially completed within 10 min with 3 wt% nano-MgO and the methanol/oil molar rate 36:1. Such high reaction rate with nano-MgO was mainly owing to the lower activation energy (75.94 kJ/mol) and the higher stirring.

OBJECTIVE To analyze the long-term effects of treatment with an operation + postoperative irradiation (A group) and an operation+intraoperative radiotherapy+postoperative irradiation (B group) in non-small cell lung cancer patients. METHODS Through a prospective randomized clinical trial, a total of 154 patients with non-small cell lung carcinoma were divided into two groups of 77 cases. Among the 154 cases, there were 134 squamous carcinomas, 17 adenocarcinomas and 3 adeno-squamous carcinomas. TNM staging: there were 17 in StageⅠ, 76 in Stage Ⅱ and 61 in Stage Ⅲ. A dosage of 15~25 Gy IORT, energy 9~16 MeV electrons, was delivered to the tumors. The doses given were 40~60 Gy postoperation. RESULTS The local control rates in A and B groups were 49.4% and 62.3% respectively ( P 0.05). There were 16 deaths from radiotherapy complications, with 2 cases in group A and 14 in group B. CONCLUSION IORT+postoperative irradiation can enhance the local control rate of non-small cell lung cancer patients and reduce the recurrent rates, but it can not improve long-term survival.

As functionalities in mobile devices have increased significantly in recent years, they have become primary means for staying connected through emails, instant messaging, voice and video calls. These services rely on mobile networks data connection or Wi-Fi connections which are cheaper and faster. They enable communications while moving from one location to another, but during the process of roaming the connections are predisposed to interruptions as the user gets out of the signal range. The current solution is to have multiple relay/repeater access points, nevertheless, short interruptions cause data integrity corruption and also use additional energy cost on the limited battery. To mitigate these issues, we propose a Wi-Fi roaming algorithm capable of automatically switching between access points while maintaining the data stream's integrity. After implementation and evaluation of the proposed solution, further refinements are introduced such as seamless transitioning from Wi-Fi to mobile data and vice versa.

A new kinetic model and an Excel^(C) spreadsheet program for modeling the stable carbon isotope composition of natural gases is provided in this paper. The model and spreadsheet could be used to describe and predict the variances in stable carbon isotope of natural gases under both experimental and geological conditions with heating temperature or geological time. It is a user-friendly convenient tool for the modeling of isotope variation with time under experimental and geological conditions. The spreadsheet, based on experimental data, requires the input of the kinetic parameters of gaseous hydrocarbons generation. Some assumptions are made in this model: (1)the conventional (non-isotope species) kinetic parameters represent the light isotope species; (2)the initial isotopic value is the same for all parallel chemical reaction of gaseous hydrocarbons generation for simplicity, (3)the re-exponential factor ratio, ^1^3A/^1^2A, is a constant, and (4)both heavy and light isotope species have similar activation energy distribution. These assumptions are common in modeling of isotope ratios. The spreadsheet is used for searching the best kinetic parameters of the heavy isotope species to reach the minimum errors compared with experimental data, and then extrapolating isotopic changes to the thermal history of sedimentary basins. A short calculation example on the variation in @d^1^3C values of methane is provided in this paper to show application to geological conditions. ple on the variation in @d^1^3C values of methane is provided in this paper to show application to geological conditions.

In this paper, hypochlorites and peroxides worked as decontaminants for destruction of cyanide ion. Main factors influencing the residual CN- concentration after decontamination were investigated. And the amount of gasificatied HCN and ClCN formed during the decontamination were measured, and their assessments on their damage were further discussed. Results indicated that degradation rate of KCN and gaseous by-products was closely related to the type of decontaminants, their concentration of active ingredients, KCN concentration, pH value and temperature etc. Generally, hypochlorites decontaminants reacted with cyanide ion more quickly than peroxides. When the amount of hypochlorite decontaminant was high above 2 times of its stoichiometric amount, the residual CN- concentration could be down to 0.5 mg/L after 5 minutes, while for peroxides, it would take much longer for complete destruction. However, the massive gasificatied ClCN produced intensely with hypochlorites decontaminant would cause relatively larger damage depth than that of HCN with peroxides.

Pure and Cu-doped SnO2 nanofibers are synthesized via a simple electrospinning method, and characterized by transmission electron microscopy and X-ray diffraction. The sensor fabricated from Cu-doped SnO2 nanofibers exhibits improved sensing properties to ethanol at 300 °C. The sensitivity is up to 3 when this sensor is exposed to 5 ppm ethanol. The response and recovery times are about 1 and 10 s, respectively. The linear dependence of the sensitivity on the ethanol concentration is observed in the range of 5–500 ppm. Good selectivity is also observed in our studies. The results make Cu-doped SnO2 nanofibers good candidates for fabricating high performance ethanol sensors.

Pure and Pd-doped In 2 O 3 nanofibers are synthesized via a simple electrospinning method and characterized by scanning electron microscopy and X-ray diffraction. Comparing with pure In 2 O 3 nanofibers, Pd-doped In 2 O 3 nanofibers exhibit much higher sensitivity to ethanol at 200 °C. The sensor fabricated from Pd-doped In 2 O 3 nanofibers can detect ethanol down to 1 ppm (the corresponding sensitivity is 4) with good selectivity, and the response and recovery times are 1 and 10 s, respectively. The sensing mechanism and the effect of Pd doping are discussed. The results indicate that the Pd-doped In 2 O 3 nanofibers can be used to fabricate high performance ethanol sensors.

This paper reports the induced growth of high quality ZnO thin film by crystallized amorphous ZnO. Firstly amorphous ZnO was prepared by solid-state pyrolytic reaction, then by taking crystallized amorphous ZnO as seeds (buffer layer), ZnO thin films have been grown in diethyene glycol solution of zinc acetate at 80°C. X-ray Diffraction curve indicates that the films were preferentially oriented [001] out-of-plane direction of the ZnO. Atomic force microscopy and scanning electron microscopy were used to evaluate the surface morphology of the ZnO thin film. Photoluminescence spectrum exhibits a strong ultraviolet emission while the visible emission is very weak. The results indicate that high quality ZnO thin film was obtained.

One hundred and twelve patients received hematopoictic stem cell transplantation (HSCT), including 91 patients with acute leukemia, 12 patients with chronic myeioid leukemia, 7 patients with lymphoma and 2 patients with myeloma and neuroblastoma respectively. Among them, 14 patients were treated with unpurged antologous bone marrow transplantation (ABMT), 25 patients with purged antologous bone marrow transplantation (PABMT), 40 patients with antologous peripheral blood hematopoietic stem cell transplantation (APBHSCT), 24 patients with allogeneic bone marrow transplantation (Ailo-BMT), 9 patients with fetal liver hematopoietic stem cell transplantation (FLHSCT). The three year disease free survival (DFS) rates in these five groups were 68.3%, 67.5%, 69.54%, 57.12% and 33.33% respectively. The relapse rates were 30.76%, 26.80%, 20.8%, 13% and 62.5% respectively. In contrast, in the conventional chemotherapy group, the three year DFS rate and relapse rate were 7.38% and 76.4% respectively. These results indicated that the APBHSCT group had a quicker hematopoietic reconstitation with less complication of infection. All of these five transplantation groups had much higher three years disease free survival rates' than that of the conventional chemotherapy group.

We studied the growth process of nanocrystalline ZnO which grown in amorphous ZnO by photoluminescence (PL). In this process, we found a new visible emission band, the visible emission intensity increased quickly at first, then decreased exponentially, while the peaks energy has a red shift from 583nm to 615nm along with the increasing reaction temperature. The results indicate this visible emission band correlate with the nanocrystalline ZnO/amorphous ZnO interface. The interface was polarized by the activated amorphous ZnO acts with the nanocrystalline ZnO surface, thus charge carrier was self-trapped on the nanocrystalline ZnO surface and emitted visible PL by recombination. We studied the changes rule of the nanocrystalline ZnO / amorphous ZnO interface by the characteristic of visible emission.

The ZnO quantum dots prepared via the solid-state pyrolytic reaction were studied. Our studies revealed the surface of ZnO quantum dots modified by amorphous ZnO. The as prepared quantum dots with sizes varying from 2-3 nm yields a blue shift about 0.15eV and shows an enhanced ultraviolet emission of 3-5 times over that of high quality ZnO nanoparticles.

In this paper, we prepared carbon doped nanocrystalline ZnO by pyrolyzed zinc stearate at 250°C and 300°C respectively. The XRD curves indicate the sample has polycrystalline hexagonal wurtzite structure. The XRD data of the sample prepared at 250°C and 300°C has a bigger angle shift about 0.05°and 0.3°respectively. That indicate the structure of the sample has some changes. The EDS indicate the sample contains Zn, O and C. So the XRD shift may attribute to the C. The XPS indicate the C doped in the crystal lattice of ZnO of the sample prepared at 300°C, and the sample prepared at 250°C may be only a few of C doped in the crystal lattice of ZnO. The PL of the sample prepared at 300°C only has a weak ultraviolet emission, which indicates C modified the nanocrystalline ZnO surface as a non-radiative recombination center. In this process C could non-radiatively recombine the carries on the nanocrystallin ZnO surface. The sample prepared at 250°C has a strong visible emission at about 530 nm. This emission band could be attributed to oxygen vacancy because C schlepped some oxygen on the nanocrystalline ZnO surface.

Porous α-Fe2O3 nanowires are synthesized by a simple wet chemical method with a precursor of peroxyacetyl nitrate (PAN), and α-Fe2O3 nanoparticles are also synthesized in the same way except for the addition of PAN. Gas sensors are fabricated by coating the samples on ceramic tubes with Au signal electrodes and Ni-Cr heaters. A sensing investigation reveals that the porous α-Fe2O3 nanowires have a higher sensitivity compared to α-Fe2O3 nanoparticles at 260°C. The corresponding sensor response (Ra/Rg) is 18.2 at the maximum to 100 ppm acetone, and the response and recovery times are about 8 and 12 s, respectively. The porous and one-dimensional nanostructures of the porous α-Fe2O3 nanowires benefit for the gas-absorption and electrical-signal-transfer, and thus improve the sensor sensitivity consequentially.