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Remote plasma-enhanced atomic layer deposition of gallium oxide thin films with NH_3 plasma pretreatment 被引量:2
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作者 Hui Hao Xiao Chen +9 位作者 Zhengcheng Li Yang Shen Hu Wang Yanfei Zhao Rong Huang Tong Liu Jian Liang Yuxin An Qing Peng Sunan Ding 《Journal of Semiconductors》 EI CAS CSCD 2019年第1期91-97,共7页
High quality gallium oxide(Ga_2O_3) thin films are deposited by remote plasma-enhanced atomic layer deposition(RPEALD) with trimethylgallium(TMG) and oxygen plasma as precursors. By introducing in-situ NH3 plasma pret... High quality gallium oxide(Ga_2O_3) thin films are deposited by remote plasma-enhanced atomic layer deposition(RPEALD) with trimethylgallium(TMG) and oxygen plasma as precursors. By introducing in-situ NH3 plasma pretreatment on the substrates, the deposition rate of Ga_2O_3 films on Si and GaN are remarkably enhanced, reached to 0.53 and 0.46 ?/cycle at 250 °C,respectively. The increasing of deposition rate is attributed to more hydroxyls(–OH) generated on the substrate surfaces after NH3 pretreatment, which has no effect on the stoichiometry and surface morphology of the oxide films, but only modifies the surface states of substrates by enhancing reactive site density. Ga_2O_3 film deposited on GaN wafer is crystallized at 250 °C, with an epitaxial interface between Ga_2O_3 and GaN clearly observed. This is potentially very important for reducing the interface state density through high quality passivation. 展开更多
关键词 Ga-oxide RPEALD PASSIVATION NH3 plasma
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夏季柴油车冷、热启动条件下NO_(x)和NH_3排放特征分析
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作者 冯谦 沈秀娥 +3 位作者 卢洋 王蓬睿 周艳青 杨妍妍 《中国环境科学》 北大核心 2026年第1期91-100,共10页
通过在重型车底盘测功机上模拟夏季柴油车在不同载荷状态下冷、热机启动过程,重点分析了柴油车在冷、热启动条件下的NO_(x)与NH_(3)排放特性及影响因素.结果表明,冷启动时排气温度与冷却液温度上升较慢,NO_(x)传感器延迟工作,82%以上的N... 通过在重型车底盘测功机上模拟夏季柴油车在不同载荷状态下冷、热机启动过程,重点分析了柴油车在冷、热启动条件下的NO_(x)与NH_(3)排放特性及影响因素.结果表明,冷启动时排气温度与冷却液温度上升较慢,NO_(x)传感器延迟工作,82%以上的NO_(x)排放发生在传感器启用前;热启动因系统温度较高,SCR与传感器快速投入运行,NO_(x)排放明显降低.NH_(3)排放受启动状态与模拟载荷影响显著,冷启动初期因SCR温度低排放因子高于平均水平;热启动时尿素快速水解且未与NO_(x)充分反应,导致NH_(3)排放增加.微观运行模态分析表明,NO_(x)排放差异主要由发动机与SCR温度决定,NH_(3)排放差异则与SCR温度及尿素喷射量相关.需要重视夏季柴油车冷机启动过程的污染物排放,协同优化启动过程的温度控制和SCR尿素喷射策略,进一步降低夏季柴油车排放对大气污染的影响. 展开更多
关键词 柴油车 夏季排放 冷热启动 NO_(x) NH_3
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Effect of activated NH_3 on SO_2 removal by pulse corona discharge plasma in flue gas
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作者 LI Jie, WU Yan, WANG Ning\|hui, YANG Li\|ming (Institute of Electrostatics, Dalian University of Technology, Dalian 116023, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2000年第4期448-451,共4页
NH 3 activated electrode is placed in front of the electrode system of pulse corona discharge plasma. There are nozzles on the electrode. Positive DC high\|voltage is applied on the nozzle\|plate gap. NH\-3 is in... NH 3 activated electrode is placed in front of the electrode system of pulse corona discharge plasma. There are nozzles on the electrode. Positive DC high\|voltage is applied on the nozzle\|plate gap. NH\-3 is injected into the reactor through nozzles, at the same time, activated and treated. These nozzles were proposed in order to make the additional gas pass through corona discharge regions near the tip of nozzles and increase the mount of radicals. The aim is to improve the De\|SO\-2 efficiency by pulse discharge plasma in flue gas. The following topics are investigated and discussed in the paper: De\|SO\-2 effect of single NH\-3\|activated electrode, De\|SO\-2 effect of activated NH\-3, the relationship between stoichiometric ratio of NH\-3 to SO\-2 and De\|SO\-2 effect of activated NH\-3, mechanism of activated NH\-3 De\|SO\-2 effect. The experimental result indicates that the De\|SO\-2 efficiency can be increased 5%—10% by activated NH\-3 on the original base of De\|SO\-2 efficiency. 展开更多
关键词 activated NH_3 De-SO_2 pulse discharge
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Si-SiO_2 interface passivation by plasma NH_3 and atomic H
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作者 WEBER K.J. JAYAPRASAD A. +1 位作者 SMITH P.J. BLAKERS A. 《Rare Metals》 SCIE EI CAS CSCD 2006年第z1期146-149,共4页
Plasma ammonia treatment at 400 ℃ leads to de-passivation of a fully hydrogenated Si-SiO2 interface, and to passivation of a fully de-hydrogenated Si-SiO2 interface. Plasma NH3 exposure causes irreversible Si surface... Plasma ammonia treatment at 400 ℃ leads to de-passivation of a fully hydrogenated Si-SiO2 interface, and to passivation of a fully de-hydrogenated Si-SiO2 interface. Plasma NH3 exposure causes irreversible Si surface damage and degradation of thermal stability. Atomic hydrogen exposure, although it results in similar effects on the Si-SiO2 interface, does not introduce additional defects or a decrease of the Si surface thermal stability. The difference between plasma NH3 exposure and atomic H exposure is speculated to be due to either the nitridation of Si-SiO2 interface or radiation damage resulting from plasma NH3 exposure. EPR measurements indicate changes of the paramagnetic defect properties and an increase in the paramagnetic defect density generated by plasma NH3 exposure. 展开更多
关键词 plasma NH3 atomic H SiO2 EPR
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The effects of process conditions on the plasma characteristic in radio-frequency capacitively coupled SiH_4/NH_3/N_2 plasmas: Two-dimensional simulations
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作者 刘相梅 宋远红 +1 位作者 姜巍 易林 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第4期338-343,共6页
A two-dimensional (2D) fluid model is presented to study the behavior of silicon plasma mixed with SiH4 , N2 , and NH3 in a radio-frequency capacitively coupled plasma (CCP) reactor. The plasma–wall interaction ... A two-dimensional (2D) fluid model is presented to study the behavior of silicon plasma mixed with SiH4 , N2 , and NH3 in a radio-frequency capacitively coupled plasma (CCP) reactor. The plasma–wall interaction (including the deposition) is modeled by using surface reaction coefficients. In the present paper we try to identify, by numerical simulations, the effect of variations of the process parameters on the plasma properties. It is found from our simulations that by increasing the gas pressure and the discharge gap, the electron density profile shape changes continuously from an edge-high to a center-high, thus the thin films become more uniform. Moreover, as the N2 /NH3 ratio increases from 6/13 to 10/9, the hydrogen content can be significantly decreased, without decreasing the electron density significantly. 展开更多
关键词 capacitively coupled plasma process conditions effects SiH4/NH3/N2 discharges
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Techno-economic assessment of plasma-driven air oxidation coupled with electroreduction synthesis of ammonia
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作者 Lei Xiao Shiyong Mou +7 位作者 Xiaoyu Lin Keying Wu Siyuan Liu Weidong Dai Weiping Yang Chiyao Tang Chang Long Fan Dong 《Green Energy & Environment》 2025年第9期1901-1910,共10页
Recently,the plasma-driven air oxidation coupled with electrocatalytic NO_(x)reduction reaction(pAO-eNO_(x)RR)technology for sustained NH_(3)synthesis displays the promise in tackling the high energy-consumption and c... Recently,the plasma-driven air oxidation coupled with electrocatalytic NO_(x)reduction reaction(pAO-eNO_(x)RR)technology for sustained NH_(3)synthesis displays the promise in tackling the high energy-consumption and carbon-emission associated with the Haber-Bosch process.Here,a technical and economic assessment of pAO-eNO_(x)RR technology is comprehensively undertaken to determine its feasibility as a potential substitute for the Haber-Bosch process.The technical assessment suggests that,in terms of both environmental impact and energy efficiency,N_(2)-NO-NH_(3)and N_(2)-NO_(2)^(-)-NH_(3)are presently the most effective pathways.The deep analysis of the current state-of-the-art technological performance indicates that the pAO-eNO_(x)RR technology is competitive with commercial processes in achieving large-scale NH_(3)synthesis.However,lower energy efficiency of pAO-eNO_(x)RR technology leads to high electricity costs that surpass the current market price of NH_(3).Subsequently,we conducted a comprehensive analysis which reveals that,for the economic viability of NH_(3)synthesis,an energy efficiency in the range of 33.8–38.6%must be attained.The expenses associated with plasma equipment,electrolyzer,catalysts,and NH_(3)distillation also contribute significantly to the economic burden.The further development of pAO-eNO_(x)RR technology should be centered around advancements in plasma catalysts,electrocatalysts,reactors,as well as the exploration for energy-efficient cathode-anode synergistic catalytic systems. 展开更多
关键词 NH_(3)synthesis ELECTROCATALYSIS Techno-economic assessment plasma NO_(x)reduction
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A membrane-based plasma separator coupled with ratiometric fluorescent sensor for biochemical analysis in whole blood
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作者 Fangbing Wang Qiankun Zeng +2 位作者 Jing Ren Min Zhang Guoyue Shi 《Chinese Chemical Letters》 2025年第7期256-261,共6页
Herein,we reported an integrated device that was utilized to directly separate plasma and analyze glucose(Glu),cholesterol(Chol)from whole blood samples.The separating module primarily consists of a porous asymmetric ... Herein,we reported an integrated device that was utilized to directly separate plasma and analyze glucose(Glu),cholesterol(Chol)from whole blood samples.The separating module primarily consists of a porous asymmetric polysulfone membrane.The vertical placement of membrane and the gravity settlement of blood cells can reduce mechanical damage to blood cells and blockage of the membrane,resulting in improved separation efficiency of the membrane.The detection module consists of a smart phone and a ratio fluorescence sensing system based on NH_(2)−MIL-53(Al)and o-phenylenediamine(OPD).The sensing system presents a dual emission response to H_(2)O_(2) the main oxidation product of Glu and Chol.Due to the fluorescence resonance energy transfer(FRET),the response of the fluorescence intensity ratio(F_(574 nm)/F_(434 nm) or F_(554 nm)/F_(434 nm))gradually increases with increasing H_(2)O_(2) concentration,accompanied by a color change from weak to strong.The visual detection of Glu and Chol can be realized through the recognition of RGB values by smart phones.The integrated device has been successfully used to analysis Glu and Chol in real blood samples,which provided a universal platform for sensing biocatalytic processes with H_(2)O_(2) production. 展开更多
关键词 NH_(2)-MIL-53(Al) CHOLESTEROL GLUCOSE COLORIMETRIC Blood plasma separation
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Utilizing BBr_(3)plasma to create high-quality solid electrolyte interphases for enhanced lithium metal anodes
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作者 Xueqi Du Ge Gao +7 位作者 Guoxiang Pan Zhong Qiu Yongqi Zhang Shenghui Shen Tianqi Yang Xinqi Liang Ping Liu Xinhui Xia 《Chinese Chemical Letters》 2025年第11期557-562,共6页
The escalating demand for advanced energy storage solutions has positioned lithium metal anodes at the forefront of battery technology research.However,the practical implementation of lithium metal anodes is impeded b... The escalating demand for advanced energy storage solutions has positioned lithium metal anodes at the forefront of battery technology research.However,the practical implementation of lithium metal anodes is impeded by challenges such as dendrite formation and the inherent instability of the native oxide layer.This study introduces a novel liquid-source plasma technique to create a high-quality solid electrolyte interphase(SEI)composed of LiBr and LiBO_(2).According to first-principal calculation,LiBO_(2)optimizes the electrochemical dynamics and LiBr improves Li diffusion at the interfaces,thus protecting the Li metal from severe Li dendrite growth.This well-designed artificial SEI endows the Li metal with remarkable cycling stability over 550 cycles at a current density of 1 m A/cm^(2),significantly superior to the bare Li anode.Meanwhile,the full cell paired with a high-voltage LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)cathode delivers long-term stability with capacity retention(78%after 200 cycles)at 1 C and excellent rate performance.The findings highlight the importance of interface engineering in optimizing battery performance and longevity. 展开更多
关键词 BBr_(3) plasma Artificial solid electrolyte interphases Lithium metal anodes In situ
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N plasma treatment on MoS_(2)-Ti_(3)C_(2) composites for improved performance in sodium ion battery
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作者 SUN Pingping LIN Zihan +6 位作者 ZHANG Haozhen WANG Yanan LI Guishun YU Anyang YU Xiao WANG Xinxin QIN Sai 《分子科学学报》 2025年第1期23-30,共8页
Molybdenum disulfide(MoS_(2))is identified as one of the most prospective anode materials for sodium ion batteries due to the special layer structure,high working potential and high theoretical capacity.Herein,N-doped... Molybdenum disulfide(MoS_(2))is identified as one of the most prospective anode materials for sodium ion batteries due to the special layer structure,high working potential and high theoretical capacity.Herein,N-doped MoS_(2)nanosheets vertically grown on Ti_(3)C_(2)layers named as N-MoS_(2)-Ti_(3)C_(2)composite has been synthesized by N plasma treatment on MoS_(2)-Ti_(3)C_(2)composite at room temperature.In sodium ion batteries,the N-MoS_(2)-Ti_(3)C_(2)electrode exhibited the initial capacity of 294.2 mAh·g^(−1)at 1 A·g^(−1),and maintained a stable specific capacity of 209.3 mAh·g^(−1)after 500 cycles,better than that of MoS_(2)-Ti_(3)C_(2)(79.0 mAh·g^(−1))and MoS_(2)(30.8 mAh·g^(−1)).The greatly enhanced high rate cycle performance for N-MoS_(2)-Ti_(3)C_(2)can be attributed to the N doping in MoS_(2)and Ti_(3)C_(2). 展开更多
关键词 MoS_(2)-Ti_(3)C_(2) N plasma sodium-ion battery
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NH_3-NH_4Cl-H_2O体系浸出低品位氧化锌矿制取电锌 被引量:21
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作者 王瑞祥 唐谟堂 +2 位作者 刘维 杨声海 张文海 《过程工程学报》 CAS CSCD 北大核心 2008年第S1期219-222,共4页
对NH_3-NH_4Cl-H_2O体系采用浸出法直接从低品位氧化锌矿提取锌,锌以锌氨配合物形式进入浸出液,浸出液中的As,Sb,Fe,SO_4^(2-)和CO_3^(2-)等杂质通过净化脱除.在最优浸出条件下,锌浸出率为88.9%;浸出液中As,Sb,Fe浓度可降至0.25 mg/L;Ca... 对NH_3-NH_4Cl-H_2O体系采用浸出法直接从低品位氧化锌矿提取锌,锌以锌氨配合物形式进入浸出液,浸出液中的As,Sb,Fe,SO_4^(2-)和CO_3^(2-)等杂质通过净化脱除.在最优浸出条件下,锌浸出率为88.9%;浸出液中As,Sb,Fe浓度可降至0.25 mg/L;CaCl_2,BaCl_2可将CO_3^(2-)和SO_4^(2-)几乎除尽,其他杂质元素含量也极低,浸出液经锌粉1次净化除杂后进行电积制取电锌.电锌中Zn的质量分数达99.999%,杂质含量极低,其中Fe的质量分数仅为0.00005%;电流效率高达96.35%,直流电耗为2502kW·h;电解废液经补充氨后返回浸出. 展开更多
关键词 NH_3-NH_4Cl-H_2O体系 低品位氧化锌矿 浸出 净化 电积
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海绵铁负载锰脱硝催化剂的制备及性能研究
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作者 宋博 沈振兴 +4 位作者 王紫彤 彭勤 徐红梅 杨柳 莫欣雨 《西安交通大学学报》 北大核心 2026年第1期41-52,共12页
针对氮氧化物(NO_(x))污染控制问题,研究了一种基于海绵铁(HMT)负载锰的高效NH_(3)选择性催化还原(NH_(3)-SCR)脱硝催化剂。使用2 mol/L硝酸对HMT进行改性,并在此基础上浸渍负载锰前驱体(质量分数为15%)后,经450℃煅烧获得脱硝催化剂HMT... 针对氮氧化物(NO_(x))污染控制问题,研究了一种基于海绵铁(HMT)负载锰的高效NH_(3)选择性催化还原(NH_(3)-SCR)脱硝催化剂。使用2 mol/L硝酸对HMT进行改性,并在此基础上浸渍负载锰前驱体(质量分数为15%)后,经450℃煅烧获得脱硝催化剂HMT-2M-15Mn-450。在固定床反应器中,研究了HMT-2M-15Mn-450的脱硝活性、抗硫抗水性和长时间使用稳定性等。通过X射线衍射、X射线光电子能谱和扫描电镜等表征手段,研究了HMT-2M-15Mn-450催化剂中锰和HMT的相互作用。研究表明:在空速为50000 m^(3)/h时,HMT-2M-15Mn-450在200~250℃的NO转化率超过90%;HMT-2M-15Mn-450在200℃连续使用12 h后NO转化率仍超过95%,且具有较强的抗硫抗水中毒性能。研究结果可为铁基矿物材料在烟气脱硝领域的资源化高值利用提供参考。 展开更多
关键词 海绵铁 NH_(3)-选择性催化还原 催化剂 氮氧化物 脱硝
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不同氮源对温带森林土壤活性有机碳、环境因子的影响及其相互作用
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作者 赵涵 左甜 +4 位作者 刁静文 苗梦雨 张晓慧 高哲 郭鹏 《环境科学》 北大核心 2026年第1期573-580,共8页
活性有机碳[易氧化有机碳(EOC)和可溶性有机碳(DOC)]作为土壤总有机碳(TOC)中最活跃的组分,对土壤环境因子的变化极为敏感.大量研究已证实,大气氮沉降的加剧显著影响了活性有机碳的含量.然而,不同类型的氮源化学性质差异明显,导致其对... 活性有机碳[易氧化有机碳(EOC)和可溶性有机碳(DOC)]作为土壤总有机碳(TOC)中最活跃的组分,对土壤环境因子的变化极为敏感.大量研究已证实,大气氮沉降的加剧显著影响了活性有机碳的含量.然而,不同类型的氮源化学性质差异明显,导致其对活性有机碳的影响可能存在差异.以典型温带森林土壤为研究对象,开展连续4 a氮沉降模拟实验[施氮量均为10g·(m^(2)·a)^(-1)],比较施加硝酸钠(NaNO_(3))、硝酸铵(NH_(4)NO_(3))、氯化铵(NH_(4)Cl)及尿素[CO(NH_(2))_(2)]后土壤活性有机碳、理化性质及胞外酶活性等的变化.结果表明,施氮后EOC和DOC的含量以及在TOC中的占比均显著降低(P<0.05).其中,施加氯化铵的效应最为明显(EOC/TOC和DOC/TOC降幅分别为-80.0%和-69.8%),硝酸钠次之,而施加硝酸铵和尿素后活性有机碳变化相对较小.随机森林模型表明,土壤理化性质(pH和总氮)和活性有机碳降解酶(转化酶和β-葡萄糖苷酶)活性是驱动活性有机碳分配比例变化的关键因子.施加氯化铵后,pH降低0.8个单位,土壤转化酶和β-葡萄糖苷酶活性分别增加22.3%和69.1%,进而加速对活性有机碳组分的分解,导致其分配比例降低.硝态氮易淋失,对有效氮含量影响较小.施加尿素后土壤酸化程度较弱,导致其对土壤酶活性的影响有限.综上所述,施氮会影响活性有机碳分配比例,但其对不同氮源的响应并不完全一致.因此,在精确评估、预测和分析氮沉降对土壤活性有机碳含量的影响时,应考虑氮源类型的影响. 展开更多
关键词 施氮 活性有机碳 铵态氮(NH_(4)^(+)-N) 硝态氮(NO_(3)^(-)-N) 土壤理化性质 土壤酶活性
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pH对生物滤池处理含H_2S和NH_3混合恶臭气体的影响 被引量:4
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作者 刘建伟 马文林 王敏 《环境污染与防治》 CAS CSCD 北大核心 2010年第9期1-4,8,共5页
研究了pH对生物滤池处理含H2S和NH3混合恶臭气体的影响,以及不同pH下的物质转化情况和去除机制。结果表明,不同pH下,生物滤池对H2S和NH3的去除率是不同的。在强酸性(pH为2左右)和中性(pH为7左右)条件下,H2S均有较好的去除效果,这分别归... 研究了pH对生物滤池处理含H2S和NH3混合恶臭气体的影响,以及不同pH下的物质转化情况和去除机制。结果表明,不同pH下,生物滤池对H2S和NH3的去除率是不同的。在强酸性(pH为2左右)和中性(pH为7左右)条件下,H2S均有较好的去除效果,这分别归于嗜酸性硫细菌和非嗜酸性硫细菌的生物降解作用。低pH下,NH3的去除归于化学中和作用;中性(pH为7左右)条件下,NH3有较高的去除率,主要依靠生物硝化作用。通过考察pH对生物滤池处理效果的影响,确定了生物滤池处理含H2S和NH3混合恶臭气体的pH控制条件和去除机制,为恶臭气体生物处理工艺的选择提供依据。 展开更多
关键词 生物滤池 H_2S NH_3 生物硝化作用
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Rapid determination of quercetin-3'-O-glucoside in rat plasma by high performance liquid chromatography-tandem mass spectrometry 被引量:2
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作者 黄慧莲 刘科兰 +4 位作者 邵峰 任刚 叶耀辉 张寿文 刘荣华 《Journal of Chinese Pharmaceutical Sciences》 CAS 2012年第3期219-225,共7页
A method for the quantification of quercetin-3’-O-glucoside in rat plasma by high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS) was developed and validated.Along with internal standard(car... A method for the quantification of quercetin-3’-O-glucoside in rat plasma by high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS) was developed and validated.Along with internal standard(carbamazepine),quercetin-3’-O-glucoside was extracted from plasma samples by simple liquid-liquid extraction with ethyl acetate.The mass spectrometry detection was set in multiple reaction monitoring(MRM) mode via positive electrospray ionization(ESI).The chromatographic run time was 3.5 min per sample.The calibration curves were linear(r^2 = 0.9992) with a lower limit of quantification(LLOQ) of 10.625 ng/mL,and the limit of detection(LOD) was 4.25 ng/mL.The intra-and inter-day precision and accuracy,in terms of relative standard deviation(RSD),were all lower than 10.44%.The recovery rate of the analyte and internal standard were higher than 66.80%.After intravenous administration of 10 mg/kg quercetin-3’-O-glucoside,the t1/2 and AUC were(0.02±0.01) h and(1.22±0.28)×10^4 μg/L·h.The method is accurate,stable and sensitive,which is suitable for the pharmacokinetic study of quercetin-3’-O-glucoside in rats. 展开更多
关键词 HPLC-MS/MS Quercetin-3 '-O-glucoside plasma concentration PHARMACOKINETICS
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预处理对CNTs低温催化氧化NH_3性能的影响 被引量:1
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作者 唐晓龙 李东 +4 位作者 王文勤 易红宏 马玎 张波文 高凤雨 《环境工程学报》 CAS CSCD 北大核心 2016年第4期1939-1944,共6页
用浓酸混合液(浓H_2SO_4)和非热等离子体(NTP)对碳纳米管(CNTs)进行预处理,对比2种方法预处理的CNTs在负载不同活性组分时NH_3的催化氧化性能,实验结果表明,浓酸混合液预处理后的CNTs,负载不同单活性组份时,NH_3转化率均低于50%,... 用浓酸混合液(浓H_2SO_4)和非热等离子体(NTP)对碳纳米管(CNTs)进行预处理,对比2种方法预处理的CNTs在负载不同活性组分时NH_3的催化氧化性能,实验结果表明,浓酸混合液预处理后的CNTs,负载不同单活性组份时,NH_3转化率均低于50%,产物中没有NO和NO_2。负载不同双活性组分时,5%Co-5%Zr/CNTs在200~225℃间,NH_3的转化效率达到55%。NTP预处理的CNTs催化剂NH_3的氧化性能高于浓酸混合液预处理的CNTs催化剂,在250℃时5%Cu/CNTs催化剂NH_3的转化率基本接近90%。而250℃时,5%Cu-5%Zr/CNTs催化剂NH_3转化率约为80%,NO的生成率约为75%,NO_2生成率约3%。 展开更多
关键词 CNTS 预处理 NH_3选择催化氧化
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Cu/SiO_(2)催化剂的制备及其乙醇脱氢制乙醛性能
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作者 魏浩宇 李晓晨 +4 位作者 苏振宇 王春雪 宋诗鹏 王国玮 祝晓琳 《石化技术与应用》 2026年第1期8-12,19,共6页
分别采用NH_(3)蒸发法和浸渍法制备了一系列Cu/SiO_(2)催化剂,利用X射线粉末衍射仪、全自动多用吸附仪、物理吸附仪、透射电子显微镜等仪器对上述催化剂进行了表征,考察了催化剂制备参数和反应条件对乙醇脱氢反应性能的影响。结果表明:... 分别采用NH_(3)蒸发法和浸渍法制备了一系列Cu/SiO_(2)催化剂,利用X射线粉末衍射仪、全自动多用吸附仪、物理吸附仪、透射电子显微镜等仪器对上述催化剂进行了表征,考察了催化剂制备参数和反应条件对乙醇脱氢反应性能的影响。结果表明:相比浸渍法,NH_(3)蒸发法制备的催化剂的活性组分金属Cu分散得更均匀,在乙醇脱氢反应中呈现出更高的催化活性;NH_(3)蒸发法制备的催化剂在Cu负载量(质量分数)为5%,反应温度为320℃,进料质量空速为2 h-1的优化条件下,乙醇转化率约为85.0%,乙醛选择性高于95.0%,且在60 h内呈现出良好的反应稳定性。 展开更多
关键词 Cu/SiO_(2)催化剂 制备方法 NH_(3)蒸发法 金属负载量 乙醇脱氢 乙醛 稳定性 选择性
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分子筛负载V_2 O_5催化剂在NH_3选择还原Nox反应中的性能 被引量:1
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作者 林德海 王虹 +3 位作者 王军利 冀德坤 李翠清 宋永吉 《工业催化》 CAS 2010年第7期71-74,共4页
以分子筛为载体,采用低温浸渍法制备负载V_2O_5催化剂。采用XRD、FT-IR和SEM等手段对催化剂进行表征,并在固定床微型反应器中对催化剂活性进行评价。结果表明,以PSRY为载体的V_2O_5/PSRY催化剂活性较好,金属助剂Cu(Cu与V物质的量比为0.1... 以分子筛为载体,采用低温浸渍法制备负载V_2O_5催化剂。采用XRD、FT-IR和SEM等手段对催化剂进行表征,并在固定床微型反应器中对催化剂活性进行评价。结果表明,以PSRY为载体的V_2O_5/PSRY催化剂活性较好,金属助剂Cu(Cu与V物质的量比为0.1)的加入使V_2O_5/PSRY催化剂活性提高,T(85)为231℃。 展开更多
关键词 催化化学 NH_3 选择性还原 V_2O_5/PSRY 分子筛 金属助剂
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[Li…X]e^(-[1])(X=FH,OH_2,NH_3)的光电性质从头算 被引量:2
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作者 王洪涛 韩奎 李艳 《物理化学学报》 SCIE CAS CSCD 北大核心 2007年第9期1468-1472,共5页
在MP2理论水平上采用6-311G基组系列计算了一价阴离子van der Waals复合物[Li…X]e^(-[1])(X=FH,OH_2,NH_3)的偶极矩(μ)、平均极化率(α)以及平均一阶超极化率(β),讨论了基组效应和电子相关效应对计算结果的影响,比较了价电子对复合... 在MP2理论水平上采用6-311G基组系列计算了一价阴离子van der Waals复合物[Li…X]e^(-[1])(X=FH,OH_2,NH_3)的偶极矩(μ)、平均极化率(α)以及平均一阶超极化率(β),讨论了基组效应和电子相关效应对计算结果的影响,比较了价电子对复合物一阶超极化率的贡献.在MP4(SDQ)/6-311++G(2df,2pd)水平上计算得到[Li…FH]e^(-[1])的μ=2.5633 a.u.,α=1.0476×10~3 a.u.,β=1.0948×10~5 a.u.;[Li…OH_2]e^(-[1])的μ=2.3204 a.u.,α=1.2201×10~3 a.u.,β= 2.1410×10~5 a.u.;[Li…NH_3]e^(-[1])的μ=2.4687 a.u.,α=1.4817×10~3 a.u.,β=3.4040×10~5 a.u.,计算结果表明,三种一价阴离子复合物分子均具有非常大的一阶超极化率,而一个价电子对复合物的一阶超极化率的贡献超过1.0×10~5 a.u.. 展开更多
关键词 非线性光学 一阶超极化率 从头算 )(X=FH OH_2 NH_3) HOMO
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Mechanism of enhancing NH_(3)-SCR performance of Mn-Ce/AC catalyst by the structure regulation of activated carbon with calcite in coal
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作者 NIU Jian LI Yuhang +4 位作者 BAI Baofeng WEN Chaolu LI Linbo ZHANG Huirong GUO Shaoqing 《燃料化学学报(中英文)》 北大核心 2026年第1期69-79,共11页
To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content ... To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content in coal)catalysts were prepared by the incipient wetness impregnation method,followed by acid washing to remove calcium-containing minerals.Comprehensive characterization and low-temperature denitrification tests revealed that calcite-induced structural modulation of coal-derived AC significantly enhances catalytic activity.Specifically,NO conversion increased from 88.3%of Mn-Ce/De-AC to 91.7%of Mn-Ce/De-AC-1CaCO_(3)(210℃).The improved SCR denitrification activity results from the enhancement of physicochemical properties including higher Mn^(4+)content and Ce^(4+)/Ce^(3+)ratio,an abundance of chemisorbed oxygen and acidic sites,which could strengthen the SCR reaction pathways(richer NH_(3)activated species and bidentate nitrate active species).Therefore,NO removal is enhanced. 展开更多
关键词 CALCITE activated carbon structure Mn-Ce/AC catalyst NH_(3)-SCR performance
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17α,20β-DIHYDROXY-4-PREGNENE-3-ONE SUPPRESSES PLASMA IgM LEVELS IN RAINBOW TROUT (Oncorhynchus mykiss)
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作者 侯亚义 韩晓冬 铃木让 《Zoological Research》 CAS CSCD 2000年第2期97-102,共6页
The relationships between 17α,20β dihydroxy 4 pregnene 3 one (17α,20β DP) and plasma IgM and total protein levels were investigated in rainbow trout, Oncorhynchus mykiss .IgM and total protein levels decre... The relationships between 17α,20β dihydroxy 4 pregnene 3 one (17α,20β DP) and plasma IgM and total protein levels were investigated in rainbow trout, Oncorhynchus mykiss .IgM and total protein levels decreased in both sexes of mature rainbow trout when 17α,20β DP levels increased during the spawning season,while the elevated 17α,20β DP suppressed IgM levels and reversibly enhanced total protein concentrations in immature trout.This represents the first report of the effect of 17α,20β DP on fish immunity.These data suggest that the increase of 17α,20β DP in spawning season may be related to infectious skin diseases. 展开更多
关键词 Rainbow trout Immunoglobulin M 17α 20β-dihydroxy-4-pregnene-3-one plasma total protein concentration
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