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在无水氨气中氮化的氧化物击穿特性的研究
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作者 林国兴 陈斗南 《华南师范大学学报(自然科学版)》 CAS 1993年第1期10-16,共7页
本研究采用在无水氨气中进行氮化氧化物的方法,提高了氧化物的击穿特性.对击穿机理及其处理程序的关系作了较详细的阐述,同时采用照相蚀刻技术,显微镜观察和扫描电子显微镜检测、能谱图等手段、取得了一批较准确的数据和样品.获得在无... 本研究采用在无水氨气中进行氮化氧化物的方法,提高了氧化物的击穿特性.对击穿机理及其处理程序的关系作了较详细的阐述,同时采用照相蚀刻技术,显微镜观察和扫描电子显微镜检测、能谱图等手段、取得了一批较准确的数据和样品.获得在无水氨气中氮化的氧化物击穿特性得到改善的结果,并指出击穿的碰撞电离机理和氮化对改善击穿特性的要点以及控制永久性击穿的决定因素. 展开更多
关键词 氮化氧化物 介质薄膜 击穿特性
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覆盖Si_3N_4层和栅氧化物氮化对晶体管的影响
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作者 柳海生 李翠 《微处理机》 2006年第5期4-5,8,共3页
研究了在各种各样的晶体管中高于最低限度的坡面外层上覆盖硅氮化物和栅氧化物被氮化的影响,同时制作出具有高、低压晶体管的硅晶片。当干燥氧化物和降低化学蒸汽的压力使之凝固的2个步骤(LPCVD)被用于厚栅氧化物时,薄栅氧化物被氮氧化... 研究了在各种各样的晶体管中高于最低限度的坡面外层上覆盖硅氮化物和栅氧化物被氮化的影响,同时制作出具有高、低压晶体管的硅晶片。当干燥氧化物和降低化学蒸汽的压力使之凝固的2个步骤(LPCVD)被用于厚栅氧化物时,薄栅氧化物被氮氧化改善。薄栅氧化物的厚度是4.5nm,厚栅氧化物的厚度为29nm。低压nMOS和pMOS不显示出任何驼峰,高压pMOS也一样。高压nMOS高于最低限度的驼峰取决于工艺条件。它表明没有覆盖硅氮化层的严重驼峰取决于经过LPCVD的内部涂层氧化沉淀后化学处理期间的湿度扩散。这说明,采用氮氧化物阻止水汽扩散防止驼峰的方法是有效的。 展开更多
关键词 CMOS 高压nMOS 驼峰 经过氮化的栅氧化物 氮化
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N_2O氧化制备MISiC氢传感器的响应特性分析 被引量:2
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作者 韩弼 徐静平 +1 位作者 黎沛涛 李艳萍 《传感技术学报》 CAS CSCD 2004年第2期285-288,共4页
采用N2 O氮化氧化技术制备氮化氧化物作为绝缘层制备金属 -绝缘体 -SiC(MISiC)肖特基势垒二极管(SBD)气体传感器的技术 ,对传感器的响应特性进行了研究。实验结果表明 ,N2 O工艺能明显改善栅绝缘层和衬底之间的界面特性从而提高传感器... 采用N2 O氮化氧化技术制备氮化氧化物作为绝缘层制备金属 -绝缘体 -SiC(MISiC)肖特基势垒二极管(SBD)气体传感器的技术 ,对传感器的响应特性进行了研究。实验结果表明 ,N2 O工艺能明显改善栅绝缘层和衬底之间的界面特性从而提高传感器的性能 ,可在高温 (如 30 0℃ )等恶劣环境下长期可靠的工作 ,且适当增加绝缘层厚度有助于传感器灵敏度和可靠性的改进。 展开更多
关键词 氮化氧化物 金属-绝缘体-SiC(MISiC) 肖特基势垒二极管 气体传感器
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退火工艺对LaTiON和HfLaON存储层金属-氧化物-氮化物-氧化物-硅存储器特性的影响 被引量:1
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作者 朱剑云 刘璐 +1 位作者 李育强 徐静平 《物理学报》 SCIE EI CAS CSCD 北大核心 2013年第3期451-456,共6页
采用反应溅射法,分别制备以LaTiON,HfLaON为存储层的金属-氧化物-氮化物-氧化物-硅电容存储器,研究了淀积后退火气氛(N2,NH3)对其存储性能的影响.分析测试表明,退火前LaTiON样品比HfLaON样品具有更好的电荷保持特性,但后者具有更大的存... 采用反应溅射法,分别制备以LaTiON,HfLaON为存储层的金属-氧化物-氮化物-氧化物-硅电容存储器,研究了淀积后退火气氛(N2,NH3)对其存储性能的影响.分析测试表明,退火前LaTiON样品比HfLaON样品具有更好的电荷保持特性,但后者具有更大的存储窗口(编程/擦除电压为+/12V时4.8V);对于退火样品,由于NH3的氮化作用,NH3退火样品比N2退火样品表现出更快的编程/擦除速度、更好的电荷保持特性和疲劳特性.当编程/擦除电压为+/-12V时,NH3退火HfLaON样品的存储窗口为3.8V,且比NH3退火LaTiON样品具有更好的电荷保持特性和疲劳特性. 展开更多
关键词 金属-氧化物-氮化物-氧化物-硅存储器 LaTiON HfLaON 退火
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MISiC高温氢气传感器研究 被引量:6
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作者 陈卫兵 宋跃 《微电子学》 CAS CSCD 北大核心 2003年第5期380-382,共3页
 文章报道了采用NO直接氧化制备氮化氧化物作绝缘层,制备高灵敏度MISiC肖特基二极管式高温气体传感器的技术。采用NO直接氧化法,改善了器件的界面特性。实验结果显示,采用该方法制作的传感器具有高响应灵敏度和良好的响应重复性。
关键词 碳化硅 氢气传感器 肖特基二极管 高温传感器 氮化氧化物 NO直接氧化 氧化
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高性能Si基MOS肖特基二极管式氢气传感器研究 被引量:4
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作者 钟德刚 徐静平 《压电与声光》 CAS CSCD 北大核心 2004年第2期106-108,共3页
报道了采用NO直接氧化制备氮化氧化物作为绝缘层制备高性能Si基MOS肖特基二极管式气体传感器(SDS)的技术。实验结果显示,MOS肖特基二极管式气体传感器具有高的响应灵敏度和好的响应重复性,可以探测浓度约为10-6的氢气。因此,采用NO直接... 报道了采用NO直接氧化制备氮化氧化物作为绝缘层制备高性能Si基MOS肖特基二极管式气体传感器(SDS)的技术。实验结果显示,MOS肖特基二极管式气体传感器具有高的响应灵敏度和好的响应重复性,可以探测浓度约为10-6的氢气。因此,采用NO直接氧化法制备绝缘层是一种制备高可靠、高灵敏度Si基MOSSDS的技术。 展开更多
关键词 肖特基二极管 氢气传感器 氧化 氮化氧化物
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反熔丝的研究与应用 被引量:20
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作者 王刚 李平 +3 位作者 李威 张国俊 谢小东 姜晶 《材料导报》 EI CAS CSCD 北大核心 2011年第11期30-33,共4页
综述了ONO(氧化物-氮化物-氧化物)反熔丝、非晶硅(a-Si)反熔丝和栅氧化层反熔丝的制作工艺、性能参数及其优缺点,介绍了反熔丝器件包括反熔丝可编程只读存储器(PROM)和反熔丝现场可编程门阵列(FPGA)在器件应用、存储容量、可用门数、工... 综述了ONO(氧化物-氮化物-氧化物)反熔丝、非晶硅(a-Si)反熔丝和栅氧化层反熔丝的制作工艺、性能参数及其优缺点,介绍了反熔丝器件包括反熔丝可编程只读存储器(PROM)和反熔丝现场可编程门阵列(FPGA)在器件应用、存储容量、可用门数、工作电压和抗辐射性能等方面的研究进展,指出了反熔丝以及反熔丝器件的4个主要发展趋势,即工艺兼容、高密度、有机/柔性和新材料。 展开更多
关键词 反熔丝 氧化物-氮化物-氧化物 非晶硅 氧化 反熔丝PROM 反熔丝FPGA
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白光LED荧光粉研究及应用新进展 被引量:25
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作者 刘荣辉 何华强 +3 位作者 黄小卫 胡运生 刘元红 庄卫东 《半导体技术》 CAS CSCD 北大核心 2012年第3期221-227,共7页
基于白光发光二极管技术的迅速发展以及荧光粉对白光LED器件的发光效率、显色性和使用寿命等性能的决定性影响,系统阐述了蓝光LED芯片激发用铝酸盐、硅酸盐、氮化物和氮氧化物系列黄色、红色和绿色荧光粉的研究进展和应用现状。探讨了... 基于白光发光二极管技术的迅速发展以及荧光粉对白光LED器件的发光效率、显色性和使用寿命等性能的决定性影响,系统阐述了蓝光LED芯片激发用铝酸盐、硅酸盐、氮化物和氮氧化物系列黄色、红色和绿色荧光粉的研究进展和应用现状。探讨了上述荧光粉的研究重点、发展趋势和应用前景,指出需要进一步提高铝酸盐黄粉的发光效率,开发新型高光效氮化物和氮氧化物红粉和绿粉及其低成本制备技术,以满足高光效、高显色、低光衰型白光LED器件制作需要。 展开更多
关键词 白光LED 荧光粉 铝酸盐 硅酸盐 氮化物和氮氧化物
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Promotional effects of Zr on K^+-poisoning resistance of CeTiO_x catalyst for selective catalytic reductionof NO_x with NH_3 被引量:5
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作者 徐宝强 徐海迪 +6 位作者 林涛 曹毅 兰丽 李元山 冯锡 龚茂初 陈耀强 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1354-1361,共8页
CeTiOx and CeZrTiOx catalysts were prepared by a coprecipitation method and used for selective catalytic reduction of NOx by NH3 (NH3‐SCR). Various amounts of KNO3 were impregnated on the catalyst surface to invest... CeTiOx and CeZrTiOx catalysts were prepared by a coprecipitation method and used for selective catalytic reduction of NOx by NH3 (NH3‐SCR). Various amounts of KNO3 were impregnated on the catalyst surface to investigate the effects of Zr addition on the K+‐poisoning resistance of the CeTiOx catalyst. The NH3‐SCR performance of the catalysts showed that the NOx removal activity of the Zr‐modified catalyst after poisoning was better than that of the CeTiOx catalyst. Brunau‐er‐Emmett‐Teller data indicated that the Zr‐containing catalyst had a larger specific surface area and pore volume both before and after K+poisoning. X‐ray diffraction, Raman spectroscopy, and transmission electron microscopy showed that Zr doping inhibited anatase TiO2 crystal grain growth, i.e., the molten salt flux effect caused by the loaded KNO3 was inhibited. The Ce 3d X‐ray photoelectron spectra showed that the Ce3+/Ce4+ratio of CeZrTiOx decreased more slowly than that of CeTiOx with increasing K+loading, indicating that Zr addition preserved more crystal defects and oxygen vacancies; this improved the catalytic performance. The acidity was a key factor in the NH3‐SCR performance; the temperature‐programmed desorption of NH3 results showed that Zr doping inhibited the decrease in the surface acidity. The results suggest that Zr improved the K+‐poisoning resistance of the CeTiOx catalyst. 展开更多
关键词 Cerium-titanium mixed oxide ZIRCONIUM Potassium-poisoning resistance Selective catalytic reduction Nitrogen oxides
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Study on the Mechanism of Innovative Montmorillonite for Diarrhea Treatment
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作者 胡屹屹 苏永腾 何孔旺 《Agricultural Science & Technology》 CAS 2013年第12期1810-1812,1851,共4页
[Objective] This study aimed to investigate the mechanism of innovative montmorillonite for diarrhea treatment. [Method] Thirty healthy weanling piglets (Duroc x Landrace x Yorkshire) were randomly divided into five... [Objective] This study aimed to investigate the mechanism of innovative montmorillonite for diarrhea treatment. [Method] Thirty healthy weanling piglets (Duroc x Landrace x Yorkshire) were randomly divided into five groups and fed with basal diet, basal diet + 1 g/kg innovative montmorillonite, basal diet + 3 g/kg innovative montmorillonite, basal diet + 5 g/kg innovative montmorillonite and basal diet + 3 g/kg Bacillus subtilis microecologic agent, respectively. After four weeks, blood samples were collected via precaval vein, to detect the content of TFF3, NO and SOD in serum by ELISA kits. [Result] Compared with blank control group, the content of TFF3, NO and SOD in high-dose innovative montmorillonite group was extremely significantly increased, extremely significantly reduced and significantly in- creased, respectively; the content of TFF3 and NO in middle-dose innovative mont- morillonite group was significantly increased and significantly reduced, respectively. [Conclusion] Innovative montmorillonite may exert beneficial therapeutic actions on diarrhea by increasing TFF3 and SOD levels and decreasing NO level. 展开更多
关键词 MONTMORILLONITE DIARRHEA TFF3 NO SOD
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Field Measurement of NO2 and RNO2 by Two-Channel Thermal Dissociation Cavity Ring Down Spectrometer 被引量:2
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作者 陈剑 吴昊 +2 位作者 刘安雯 胡水明 张劲松 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第5期493-498,I0001,共7页
A two-channel thermal dissociation cavity ring down spectroscopy (CRDS) instrument has been built for in situ, real-time measurement of NO2 and total RNO2 (peroxy nitrates and alkyl nitrates) in ambient air, with ... A two-channel thermal dissociation cavity ring down spectroscopy (CRDS) instrument has been built for in situ, real-time measurement of NO2 and total RNO2 (peroxy nitrates and alkyl nitrates) in ambient air, with a NO2 detection limit of 0.10 ppbv at 1 s. A 6-day long measurement was conducted at urban site of Hefei by using the CRDS instrument with a time resolution of 3 s. A commercial molybdenum converted chemiluminescence (Mo-CL) instrument was also used for comparison. The average RNO2 concentration in the 6 days was measured to be 1.94 ppbv. The Mo-CL instrument overestimated the NO2 concentration by a bias of +1.69 ppbv in average, for the reason that it cannot distinguish RNO2 from NO2. The relative bias could be over 100% during the afternoon hours when NO2 was low but RNO2 was high. 展开更多
关键词 Cavity ring-down spectroscopy Molybdenum converted chemiluminescence Thermal dissociation Organic nitrates
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太阳能光谱选择性吸收薄膜高温性能衰减分析
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作者 魏东辉 李文哲 《太阳能学报》 EI CAS CSCD 北大核心 2016年第8期1993-1997,共5页
对SiO_2/CrO_x/CrN_y/Al型太阳能光谱选择性吸收薄膜的热稳定性进行测试,分析薄膜在高温下的光学性能、表面及截面形貌、元素分布、微观结构等变化。在450℃下热处理300 h后采用SEM、AES、TEM等方法分析薄膜热处理后的微观结构、成分变... 对SiO_2/CrO_x/CrN_y/Al型太阳能光谱选择性吸收薄膜的热稳定性进行测试,分析薄膜在高温下的光学性能、表面及截面形貌、元素分布、微观结构等变化。在450℃下热处理300 h后采用SEM、AES、TEM等方法分析薄膜热处理后的微观结构、成分变化。结果表明,经热处理薄膜出现表面粗糙度增加、晶粒异常长大、亚层界面变模糊等变化。主要的衰减机制为薄膜在高温下O、N发生轻微扩散,另外经热处理后吸收层Cr结晶度略有增加。 展开更多
关键词 太阳能光谱选择性吸收薄膜 过渡金属氧化物氮化 热稳定性 衰减机制 高温扩散
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Resistance to SO_2 poisoning of V_2O_5/TiO_2-PILC catalyst for the selective catalytic reduction of NO by NH_3 被引量:4
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作者 臧思淼 张桂臻 +3 位作者 邱文革 宋丽云 张然 何洪 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第6期888-897,共10页
A titania pillared interlayered clay(Ti-PILC) supported vanadia catalyst(V2O5/TiO2-PILC) was prepared by wet impregnation for the selective catalytic reduction(SCR) of NO with ammonia. Compared to the traditiona... A titania pillared interlayered clay(Ti-PILC) supported vanadia catalyst(V2O5/TiO2-PILC) was prepared by wet impregnation for the selective catalytic reduction(SCR) of NO with ammonia. Compared to the traditional V2O5/TiO2 and V2O5-MoO3/TiO2 catalysts, the V2O5/TiO2-PILC catalyst exhibited a higher activity and better SO2 and H2O resistance in the NH3-SCR reaction. Characterization using TPD, in situ DRIFT and XPS showed that surface sulfate and/or sulfite species and ionic SO4^(2-)species were formed on the catalyst in the presence of SO2. The ionic SO4^(2-) species on the catalyst surface was one reason for deactivation of the catalyst in SCR. The formation of the ionic SO4^(2-) species was correlated with the amount of surface adsorbed oxygen species. Less adsorbed oxygen species gave less ionic SO4^(2-) species on the catalyst. 展开更多
关键词 Selective catalytic reduction TiO2-pillared clay Nitrogen oxide Vanadia catalyst In situ diffuse reflectance infrared Fourier transform spectroscopy
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Synthesis of a chabazite-supported copper catalyst with full mesopores for selective catalytic reduction of nitrogen oxides at low temperature 被引量:9
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作者 刘计省 刘坚 +4 位作者 赵震 宋卫余 韦岳长 段爱军 姜桂元 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第5期750-759,共10页
A series of meso‐microporous copper‐supporting chabazite molecular sieve(CuSAPO‐34) catalysts with excellent performance in low‐temperature ammonia selective catalytic reduction(NH3‐SCR)have been synthesized ... A series of meso‐microporous copper‐supporting chabazite molecular sieve(CuSAPO‐34) catalysts with excellent performance in low‐temperature ammonia selective catalytic reduction(NH3‐SCR)have been synthesized via a one‐pot hydrothermal crystallization method. The physicochemical properties of the catalysts were characterized by scanning electron microscopy, transmission electron microscopy, N2 adsorption‐desorption measurements, X‐ray diffraction, 27 Al magic angle spinning nuclear magnetic resonance, diffuse reflectance ultraviolet‐visible spectroscopy, inductively coupled plasma‐atomic emission spectroscopy, X‐ray photoelectron spectroscopy, temperature‐programmed reduction measurements, and electron paramagnetic resonance analysis. The formation of micro‐mesopores in the Cu‐SAPO‐34 catalysts decreases diffusion resistance and greatly improves the accessibility of reactants to catalytic active sites. The main active sites for NH3‐SCR reaction are the isolated Cu^2+ species displaced into the ellipsoidal cavity of the Cu‐SAPO‐34 catalysts. 展开更多
关键词 One-pot synthesis Meso-microporous Cu-SAPO-34 Low temperature Selective catalytic reduction Nitrogen oxides
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New progress in roles of nitric oxide during hepatic ischemia reperfusion injury 被引量:20
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作者 Ya-Qi Zhang Ning Ding +4 位作者 Yong-Fen Zeng Yuan-Yuan Xiang Mei-Wen Yang Fen-Fang Hong Shu-Long Yang 《World Journal of Gastroenterology》 SCIE CAS 2017年第14期2505-2510,共6页
Hepatic ischemia reperfusion injury (HIRI) is a clinical condition which may lead to cellular injury and organ dysfunction. The role of nitric oxide (NO) in HIRI is complicated and inconclusive. NO produced by endothe... Hepatic ischemia reperfusion injury (HIRI) is a clinical condition which may lead to cellular injury and organ dysfunction. The role of nitric oxide (NO) in HIRI is complicated and inconclusive. NO produced by endothelial nitric oxide synthase (eNOS) activation plays a protective role during early HIRI. But eNOS overexpression and the resulting excessive NO bioavailability can aggravate liver injury. NO induced by inducible nitric oxide synthase (iNOS) may have either a protective or a deleterious effect during the early phase of HIRI, but it may protect the liver during late HIRI. Here, we reviewed the latest findings on the role of NO during HIRI: (1) NO exerts a protective effect against HIRI by increasing NO bioavailability, downregulating p53 gene expression, decreasing inflammatory chemokines, reducing ROS via inhibiting the mitochondrial respiratory chain, activating sGC-GTP-cGMP signal pathway to reduce liver cell apoptosis, and regulating hepatic immune functions; (2) eNOS protects against HIRI by increasing NO levels, several eNOS/NO signal pathways (such as Akt-eNOS/NO, AMPK-eNOS/NO and HIF-1 alpha-eNOS/NO) participating in the anti-HIRI process, and inhibiting over-expression of eNOS also protects against HIRI; and (3) the inhibition of iNOS prevents HIRI. Thus, the adverse effects of NO should be avoided, but its positive effect in the clinical treatment of diseases associated with HIRI should be recognized. 展开更多
关键词 LIVER Hepatic ischemia reperfusion injury Nitric oxide Nitric oxide synthase
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GdO存储层中氧含量及掺氮对MONOS存储器特性的影响
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作者 李育强 刘璐 +1 位作者 朱剑云 徐静平 《固体电子学研究与进展》 CAS CSCD 北大核心 2013年第1期17-21,共5页
采用反应溅射法制备以GdOx或GdON为存储层的MONOS(Metal-Oxide-Nitride-Oxide-Si)电容存储器,研究了GdOx中氧含量以及掺氮对MONOS存储器存储特性的影响。实验结果表明,含氧气氛中制备的GdO其氧空位(电荷陷阱)较少,且界面处存在较多Gd-Si... 采用反应溅射法制备以GdOx或GdON为存储层的MONOS(Metal-Oxide-Nitride-Oxide-Si)电容存储器,研究了GdOx中氧含量以及掺氮对MONOS存储器存储特性的影响。实验结果表明,含氧气氛中制备的GdO其氧空位(电荷陷阱)较少,且界面处存在较多Gd-Si键,导致界面态密度增加,因而存储特性欠佳;引入氮至GdO中可诱导出大量的深能级电子陷阱,并能提高介电常数、减少界面缺陷,因此GdON样品表现出好的存储特性:较大的存储窗口(±13V/1s的编程/擦除电压下,存储窗口4.1V)、高的工作速度、好的保持特性以及优良的疲劳特性(105循环编程/擦除后,存储窗口几乎不变)。 展开更多
关键词 金属-氧化物-氮化物-氧化物硅存储器 存储特性 氧化 氧化
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Removal of SO_2 and NO_x by Pulsed Corona Combined with in situ Ca(OH)2 Absorption 被引量:12
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作者 黄立维 党永霞 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第3期518-522,共5页
Removal of SO2 and NOx by pulsed corona combined with in situ alkali absorption was experimentally investigated.In the reactor,a plate-wire-plate combination is devised for generating pulsed corona and then alkaline a... Removal of SO2 and NOx by pulsed corona combined with in situ alkali absorption was experimentally investigated.In the reactor,a plate-wire-plate combination is devised for generating pulsed corona and then alkaline absorbent slurries were introduced into the reactor by a continuous band conveying system to capture the gaseous reaction products.It was found that both SO2 and NO could be removed by corona combined with in situ alkali absorption.The removal of SO2 increased to 75%with the corona discharge,compared with 60%removal only with Ca(OH)2 absorption.About 40%removal of NO was reached by pulsed corona combined with in situ Ca(OH)2 absorption.It was found that SO2 and NO in the gas stream are oxidized to SO3 and NO2 by pulsed corona respectively,and then absorbed by the alkali in the reactor.The removals of SO2 as well as NO were higher with Ca(OH)2 as the absorbent,compared with using CaCO3 or ZnO. 展开更多
关键词 pulsed corona ABSORPTION DENITRIFICATION DESULFURIZATION REMOVAL Ca(OH)2
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Imbalanced free radicals and antioxidant defense systems in schizophrenia:A comparative study 被引量:7
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作者 LI Hui-chun CHEN Qiao-zhen MA Ying ZHOU Jun-fu 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第12期981-986,共6页
Objective: To examine changes of blood oxidative-antiovidative level in schizophrenic patients and its relationship with clinical symptoms. Methods: Forty-six Chinese patients met DSM-IV (Diagnostic and Statistical Ma... Objective: To examine changes of blood oxidative-antiovidative level in schizophrenic patients and its relationship with clinical symptoms. Methods: Forty-six Chinese patients met DSM-IV (Diagnostic and Statistical Manual of Mental Disor- ders-IV) criteria for schizophrenia and fifty age- and sex-matched healthy controls were enrolled in the present study. Baseline psychiatric symptom severity was assessed with brief psychiatric rating scale, positive and negative syndrome scale on the blood draw day. Fresh blood samples were collected to measure levels of nitric oxide and lipid peroxide in plasma as well as activities of superoxide dismutase, catalase and glutathione peroxidase in red blood cells by spectrophotometric assays simultaneously. Results: Comparison of the biochemical parameters indicated that the level of nitric oxide and lipid peroxide increased in patient group, which represented a positive correlation with positive scale scores; while the activities of three critical enzymes decreased and showed a negative linear correlation. Conclusion: This study showed that there are dysregulation of free radical metabolism and poor activities of the antioxidant defense systems in schizophrenic patients. Excess free radicals formation may play a critical role in the etiology of schizophrenia. Using antioxidants might be an effective therapeutic approach to partially alleviate or prevent the symptoms of schizophrenia. 展开更多
关键词 SCHIZOPHRENIA Nitric oxide (NO) Lipid peroxide (LPO) Glutathione peroxidase (GSH-Px) Catalase (CAT) Superoxide dismutase (SOD) Symptom
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Influence of sulfation on CeO_2-ZrO_2 catalysts for NO reduction with NH_3 被引量:5
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作者 He Zhang Yonggang Zou Yue Peng 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第1期160-167,共8页
CeO2‐ZrO2 (CeZr) and sulfated CeO2‐ZrO2 (S‐CeZr) catalysts were prepared for the selective catalytic reduction of NO with NH3. The CeZr catalysts exhibited higher activity at low temperatures (< 200°C) and ... CeO2‐ZrO2 (CeZr) and sulfated CeO2‐ZrO2 (S‐CeZr) catalysts were prepared for the selective catalytic reduction of NO with NH3. The CeZr catalysts exhibited higher activity at low temperatures (< 200°C) and lower activity at high temperatures (> 200 °C) than the S‐CeZr catalysts. The sulfation ofCeZr was studied in terms of surface acidity, redox properties and NO adsorption‐desorption bytemperature‐dependent experiments and in situ infrared spectroscopy. S‐CeZr displayed high concentrationsof acidic sites and increased surface acidities, but poor reducibility compared with CeZr.The high acidity of S‐CeZr was attributed to the presence of Br?nsted acid sites, arising mainly fromthe surface sulfates. Because the surface was covered with sulfate species, S‐CeZr showed lower NOadsorption and weaker oxidation ability than CeZr. The adsorption of NH3 on the Br?nsted acid sites restricted the reaction with NO at low temperatures, but the selective catalytic reduction cycle occurred easily at relatively low temperatures (150 °C), and the weakly bound nitrite was partially activated on the S‐CeZr catalyst at relatively high temperatures (300 °C). The catalytic mechanisms for the CeZr and S‐CeZr catalysts at 150 and 300 °C were also studied. 展开更多
关键词 SULFATION Removal of nitrogen oxides Selective catalytic reduction CERIA ZIRCONIA
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Promotional effects of Er incorporation in CeO_2(ZrO_2)/TiO_2 for selective catalytic reduction of NO by NH_3 被引量:4
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作者 Qijie Jin Yuesong Shen +2 位作者 Shemin Zhu Xihong Li Min Hu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第9期1521-1529,共9页
A series CeO2(ZrO2)/TiO2 catalysts were modified with Er using a sol-gel method.The catalytic activity of the obtained catalysts in the selective catalytic reduction(SCR) of NO with NH3 was investigated to determi... A series CeO2(ZrO2)/TiO2 catalysts were modified with Er using a sol-gel method.The catalytic activity of the obtained catalysts in the selective catalytic reduction(SCR) of NO with NH3 was investigated to determine the appropriate Er dosage.The catalysts were characterized using X-ray diffraction,N2 adsorption,NH3 temperature-programmed desorption,H2 temperature-programmed reduction,photoluminescence spectroscopy,electron paramagnetic resonance spectroscopy,and X-ray photoelectron spectroscopy.The results showed that the optimum Er/Ce molar ratio was 0.10;this catalyst had excellent resistance to catalyst poisoning caused by vapor and sulfur and gave more than 90% NO conversion at 220–395 ℃ and a gas hourly space velocity of 71 400 h^-1.Er incorporation increased the Ti^3+ concentrations,oxygen storage capacities,and oxygen vacancy concentrations of the catalysts,resulting in excellent catalytic performance.Er incorporation also decreased the acid strength and inhibited growth of TiO2 and CeO2 crystal particles,which increased the catalytic activity.The results show that high oxygen vacancy concentrations and oxygen storage capacities,large amounts of Ti^3+,and low acid strengths give excellent SCR activity. 展开更多
关键词 CeO2(ZrO2)/TiO2 Erbium incorporation Selective catalytic reduction Nitrogen oxide Catalytic performance
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