To facilitate potential applications of tungsten diselenide （WSe2） in electronics, controllable doping is of great importance. As an industrially compatible technology, plasma treatment has been used to dope two-dim...To facilitate potential applications of tungsten diselenide （WSe2） in electronics, controllable doping is of great importance. As an industrially compatible technology, plasma treatment has been used to dope two-dimensional （2D） materials. However, owing to the strong etching effect in transition metal dichalcogenides （TMDCs）, it is difficult to controllably dope 2D WSe2 crystals by plasma. Herein, we develop a moderate ammonia plasma treatment method to prepare nitrogen-doped WSe2 with controlled nitrogen content. Interestingly, Raman, photoluminescence, X-ray photoelectron spectroscopy, and electrical Lts reveal abnormal n-doping behavior of nitrogen-doped WSe2, which is attributed to selenium anion vacancy introduced by hydrogen species in ammonia plasma. Nitrogen-doped WSe2 with abnormal n-doping behavior has potential applications in future TMDCs-based electronics.展开更多
目的探讨伴中央颞区棘波的儿童自限性癫痫(self-limited epilepsy in children with spines in the central temporal region,SeLECTS)发作与血浆氨及25羟维生素D[25-hydroxyvitamin D,25(OH)D]水平相关性。方法选取2021年9月至2023年1...目的探讨伴中央颞区棘波的儿童自限性癫痫(self-limited epilepsy in children with spines in the central temporal region,SeLECTS)发作与血浆氨及25羟维生素D[25-hydroxyvitamin D,25(OH)D]水平相关性。方法选取2021年9月至2023年10月安徽医科大学附属宿州医院收治的90例SeLECTS患儿为病例组,同期90例宿州地区健康体检儿童为对照组,比较两组研究对象的血浆氨及血清25(OH)D水平差异,回顾分析SeLECTS临床特点与血浆氨及25(OH)D水平的相关性。结果病例组患儿的血浆氨浓度高于对照组(P<0.05),25(OH)D水平明显低于对照组(P<0.05)。不同发病年龄、发作时间、发作频率的SeLECTS患儿,血浆氨浓度差异有统计学意义(P<0.05);不同发病年龄、发作频率、发作季节的SeLECTS患儿,血清25(OH)D含量差异有统计学意义(P<0.05)。发作时间与发病年龄、发病频率之间的相关性差异有统计学意义(P<0.01);而血浆氨浓度与发病年龄、发作时间、发作频率之间的相关性差异有统计学意义(P<0.05);同时25(OH)D含量与发作时间、发作频率、血浆氨浓度之间相关性差异有统计学意义(P<0.05)。SeLECTS患儿发病年龄、发作频率、发作时间与血浆氨水平呈正相关;发病年龄与25(OH)D水平呈正相关,发作频率与25(OH)D水平呈负相关。结论SeLECTS发作与血浆氨及血清25(OH)D水平之间存在相关性,血浆氨水平升高或25(OH)D水平降低皆会增加SeLECTS发作的风险。因此,通过检验患儿血浆氨及血清25(OH)D含量可为预防、病情评估及诊治SeLECTS提供依据。展开更多
An dielectric barrier discharge （DBD） system in atmospheric pressure utilized for the treatment of industrial landfill leachate is reported. The discharge parameters, such as the operating frequency, gas flow rate, ...An dielectric barrier discharge （DBD） system in atmospheric pressure utilized for the treatment of industrial landfill leachate is reported. The discharge parameters, such as the operating frequency, gas flow rate, and treating duration, were found to affect significantly the removal of ammonia nitrogen （AN） in industrial landfill leachate. An increase in treating duration leads to an obvious increase in the removal efficiency of AN （up to 83%） and the leachate color changed from deep grey-black to transparent. Thus the dielectric barrier discharges in atmospheric pressure could degrade the landfill leachate effectively. Typical waveforms of both applied voltage and discharge current were also presented for analyzing the discharge processes under different discharge parameters. Optical emission spectra measurements indicate that oxidation species generated in oxygen DBD plasma play a crucial role in removing AN, oxidizing organic and inorganic substances and decolorizing the landfill leachate.展开更多
The novel Ni-Ir/γ-Al2O3 catalyst, denoted as NIA-P, was prepared by high-frequency cold plasma direct reduction method under ambient conditions without thermal treatment, and the conventional sample, denoted as NIA-C...The novel Ni-Ir/γ-Al2O3 catalyst, denoted as NIA-P, was prepared by high-frequency cold plasma direct reduction method under ambient conditions without thermal treatment, and the conventional sample, denoted as NIA-CR, was prepared by impregnation, thermal calcination, and then by H2 reduction method. The effects of reduction methods on the catalysts for ammonia decomposition were studied, and they were characterized by XRD, N2 adsorption, XPS, and H2-TPD. It was found that the plasma-reduced NIA-P sample showed a better catalytic performance, over which ammonia conversion was 68.9%, at T = 450℃, P = 1 atm, and GHSV = 30, 000 h^-1. It was 31.7% higher than that of the conventional NIA-CR sample. XRD results showed that the crystallite size decreased for the sample with plasma reduction, and the dispersion of active components was improved. There were more active components on the surface of the NIA-P sample from the XPS results. This effect resulted in the higher activity for decomposition of ammonia. Meanwhile, the plasma process significantly decreased the time of preparing catalyst.展开更多
文摘To facilitate potential applications of tungsten diselenide （WSe2） in electronics, controllable doping is of great importance. As an industrially compatible technology, plasma treatment has been used to dope two-dimensional （2D） materials. However, owing to the strong etching effect in transition metal dichalcogenides （TMDCs）, it is difficult to controllably dope 2D WSe2 crystals by plasma. Herein, we develop a moderate ammonia plasma treatment method to prepare nitrogen-doped WSe2 with controlled nitrogen content. Interestingly, Raman, photoluminescence, X-ray photoelectron spectroscopy, and electrical Lts reveal abnormal n-doping behavior of nitrogen-doped WSe2, which is attributed to selenium anion vacancy introduced by hydrogen species in ammonia plasma. Nitrogen-doped WSe2 with abnormal n-doping behavior has potential applications in future TMDCs-based electronics.
文摘目的探讨伴中央颞区棘波的儿童自限性癫痫(self-limited epilepsy in children with spines in the central temporal region,SeLECTS)发作与血浆氨及25羟维生素D[25-hydroxyvitamin D,25(OH)D]水平相关性。方法选取2021年9月至2023年10月安徽医科大学附属宿州医院收治的90例SeLECTS患儿为病例组,同期90例宿州地区健康体检儿童为对照组,比较两组研究对象的血浆氨及血清25(OH)D水平差异,回顾分析SeLECTS临床特点与血浆氨及25(OH)D水平的相关性。结果病例组患儿的血浆氨浓度高于对照组(P<0.05),25(OH)D水平明显低于对照组(P<0.05)。不同发病年龄、发作时间、发作频率的SeLECTS患儿,血浆氨浓度差异有统计学意义(P<0.05);不同发病年龄、发作频率、发作季节的SeLECTS患儿,血清25(OH)D含量差异有统计学意义(P<0.05)。发作时间与发病年龄、发病频率之间的相关性差异有统计学意义(P<0.01);而血浆氨浓度与发病年龄、发作时间、发作频率之间的相关性差异有统计学意义(P<0.05);同时25(OH)D含量与发作时间、发作频率、血浆氨浓度之间相关性差异有统计学意义(P<0.05)。SeLECTS患儿发病年龄、发作频率、发作时间与血浆氨水平呈正相关;发病年龄与25(OH)D水平呈正相关,发作频率与25(OH)D水平呈负相关。结论SeLECTS发作与血浆氨及血清25(OH)D水平之间存在相关性,血浆氨水平升高或25(OH)D水平降低皆会增加SeLECTS发作的风险。因此,通过检验患儿血浆氨及血清25(OH)D含量可为预防、病情评估及诊治SeLECTS提供依据。
文摘An dielectric barrier discharge （DBD） system in atmospheric pressure utilized for the treatment of industrial landfill leachate is reported. The discharge parameters, such as the operating frequency, gas flow rate, and treating duration, were found to affect significantly the removal of ammonia nitrogen （AN） in industrial landfill leachate. An increase in treating duration leads to an obvious increase in the removal efficiency of AN （up to 83%） and the leachate color changed from deep grey-black to transparent. Thus the dielectric barrier discharges in atmospheric pressure could degrade the landfill leachate effectively. Typical waveforms of both applied voltage and discharge current were also presented for analyzing the discharge processes under different discharge parameters. Optical emission spectra measurements indicate that oxidation species generated in oxygen DBD plasma play a crucial role in removing AN, oxidizing organic and inorganic substances and decolorizing the landfill leachate.
基金National Natural Science Foundation of China (20590360)New Century Excellent Talent Project of China (NCET-05-0783)
文摘The novel Ni-Ir/γ-Al2O3 catalyst, denoted as NIA-P, was prepared by high-frequency cold plasma direct reduction method under ambient conditions without thermal treatment, and the conventional sample, denoted as NIA-CR, was prepared by impregnation, thermal calcination, and then by H2 reduction method. The effects of reduction methods on the catalysts for ammonia decomposition were studied, and they were characterized by XRD, N2 adsorption, XPS, and H2-TPD. It was found that the plasma-reduced NIA-P sample showed a better catalytic performance, over which ammonia conversion was 68.9%, at T = 450℃, P = 1 atm, and GHSV = 30, 000 h^-1. It was 31.7% higher than that of the conventional NIA-CR sample. XRD results showed that the crystallite size decreased for the sample with plasma reduction, and the dispersion of active components was improved. There were more active components on the surface of the NIA-P sample from the XPS results. This effect resulted in the higher activity for decomposition of ammonia. Meanwhile, the plasma process significantly decreased the time of preparing catalyst.
