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La_(1-x)Ce_(x)MnO_(3)-Ba/Al_(2)O_(3)催化剂对NO选择性生成NH_(3)的影响
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作者 宋崇林 郑庆贺 +3 位作者 吕誉 崔立峰 李云强 吕刚 《天津大学学报(自然科学与工程技术版)》 EI CAS CSCD 北大核心 2024年第10期1053-1061,共9页
为了实现碳中和目标,降低内燃机碳排放,稀薄燃烧技术成为了当前重要的研究方向.该技术不仅能提高发动机燃油热效率,还能有效降低CO_(2)排放.但是稀薄燃烧往往会伴随着大量氮氧化物的产生,为了解决该问题,采用LNT-SCR耦合的NO_(x)净化技... 为了实现碳中和目标,降低内燃机碳排放,稀薄燃烧技术成为了当前重要的研究方向.该技术不仅能提高发动机燃油热效率,还能有效降低CO_(2)排放.但是稀薄燃烧往往会伴随着大量氮氧化物的产生,为了解决该问题,采用LNT-SCR耦合的NO_(x)净化技术,此时LNT的作用是将排气中部分NO_(x)转化为NH_(3),为下游的SCR提供还原剂.基于此,制备了LNT催化剂,研究催化剂对NO选择性生成NH_(3)的影响.采用溶胶-凝胶法制备了La_(1-x)Ce_(x)MnO_(3)系列钙钛矿氧化物,并通过分步浸渍法得到了La_(1-x)Ce_(x)MnO_(3)-Ba/Al_(2)O_(3)负载型催化剂.利用XRD、H_(2)-TPR、NO-TPD等表征手段研究了钙钛矿氧化物的晶相结构,以及负载型催化剂的还原特性、NO_(x)吸附-脱附性能等物化性质,并且通过H_(2)选择性催化还原NO实验探究了催化剂掺杂Ce对NO转化成NH_(3)的影响.结果表明,Ce掺杂催化剂具有良好的NH_(3)产物选择性,并且显著提高了NO转化率.温度是NO转化和NH_(3)产物选择性生成的决定性因素,而H_(2)和NO体积比是NO转化和NH_(3)产物选择性生成的关键性因素.其中,La_(0.95)Ce_(0.05)MnO_(3)-Ba/Al_(2)O_(3)在低温下催化活性表现最佳,在350℃、H_(2)和NO体积比为5.0时NH_(3)产物选择性为65%,NO转化率为100%.此外,所制备的La_(1-x)Ce_(x)MnO_(3)都形成了钙钛矿型结构,而且Ce掺杂催化剂的大部分Ce离子可以进入到LaMnO_(3)结构中.在催化剂适量掺杂Ce后,H_(2)消耗总面积增大、还原峰的峰值温度降低,表明掺杂Ce改善了催化剂的还原特性;同时NO吸附和脱附面积增大,表明Ce掺杂改变了催化剂的NO_(x)吸附-脱附性能. 展开更多
关键词 La_(1-x)Ce_(x)MnO_(3)-Ba/al_(2)O_(3)催化剂 h_(2)选择性催化还原NO Nh_(3)产物选择性 NO转化率 晶相结构 还原特性 NO_(x)吸附-脱附
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Na_(2)CO_(3)·10H_(2)O-Na_(2)HPO_(4)·12H_(2)O/SiO_(2)复合定形相变材料的制备及应用 被引量:2
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作者 王璇 李再超 +2 位作者 吴亚楠 唐炳涛 张宇昂 《精细化工》 EI CAS CSCD 北大核心 2024年第3期623-629,656,共8页
以Na_(2)CO_(3)·10H_(2)O(SCD)、Na_(2)HPO_(4)·12H_(2)O(DHPD)为相变主体制备了共晶体系,通过绘制凝固点变化图与DSC测试共同确定在m(SCD)∶m(DHPD)=4∶6时形成共晶,FTIR和XRD结果显示,2种水合盐间没有发生化学反应,但其晶... 以Na_(2)CO_(3)·10H_(2)O(SCD)、Na_(2)HPO_(4)·12H_(2)O(DHPD)为相变主体制备了共晶体系,通过绘制凝固点变化图与DSC测试共同确定在m(SCD)∶m(DHPD)=4∶6时形成共晶,FTIR和XRD结果显示,2种水合盐间没有发生化学反应,但其晶型结构发生改变。通过添加质量分数为2%的Na2SiO3·9H_(2)O作为成核剂降低体系的过冷度,且经历50次相变循环体系未出现相分离,相变焓值仅下降0.25%。进一步使用质量分数为25%的气相SiO_(2)作为支撑材料,采用浸渍法制备了相变前后形状稳定的共晶水合盐/SiO_(2)定形相变材料(SSPCM)。所得SSPCM的相变温度为24.08℃,相变焓值为146.6J/g,过冷度为0.55℃,热导率为0.4571W/(m·K)。同保温泡沫相比,其可将模拟房内部中心温度的升温时间延长了1.81倍,降温时间延长了0.39倍。 展开更多
关键词 Na_(2)CO_(3)·10h_(2)O Na_(2)hPO_(4)·12h_(2)O 共晶水合盐 复合相变材料 建筑节能 功能材料
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用于C_(3)H_(6)/N_(2)分离的PDA@PEBA2533膜的制备
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作者 杜翠花 张茜 +2 位作者 王晓东 黄伟 周明 《化工进展》 EI CAS CSCD 北大核心 2024年第1期437-446,共10页
为回收聚丙烯制备尾气中的丙烯,采用本实验室独创的浸渍-旋转法在聚醚嵌段共聚酰胺(PEBA2533)膜表面沉积聚多巴胺(PDA)膜层制备出对C3H6具有更强亲和性的PDA@PEBA2533膜。利用扫描电子显微镜(SEM)和X射线衍射(XRD)对PDA颗粒和膜进行表... 为回收聚丙烯制备尾气中的丙烯,采用本实验室独创的浸渍-旋转法在聚醚嵌段共聚酰胺(PEBA2533)膜表面沉积聚多巴胺(PDA)膜层制备出对C3H6具有更强亲和性的PDA@PEBA2533膜。利用扫描电子显微镜(SEM)和X射线衍射(XRD)对PDA颗粒和膜进行表征。考察了PDA沉积时间对膜形貌、结构以及分离性能的影响,也考察了温度和压力等操作条件对膜分离性能的影响。探索了PDA@PEBA2533膜对不同C3H6浓度的C_(3)H_(6)/N_(2)混合气的分离效果以及膜的长时间分离稳定性。结果表明,沉积PDA于PEBA2533膜表面有效提高了膜的分离性能。当沉积时间不小于24h时,可得到连续的PDA膜层,随沉积时间的增加,膜层逐渐增厚,气体渗透速率先增大后减小,选择性持续上升,沉积24h所制备的膜分离性能最佳。增大操作温度和压力,膜对C3H6和N2的渗透速率均增大,C_(3)H_(6)/N_(2)选择性则降低。增大混合气中C3H6浓度,膜对C3H6的渗透速率和选择性均呈现先上升后下降的趋势。在所制备的分离性能最好的PDA@PEBA2533膜上,0.2MPa时,对C3H6体积分数为20%的混合气,温度从0℃提高到50℃,C3H6渗透速率从8.25GPU增加到71.42GPU,C_(3)H_(6)/N_(2)选择性从22.92降低至10.14。在130h的气体分离实验中,该膜表现出良好的稳定性。该膜与其他分离C_(3)H_(6)/N_(2)混合气膜相比具有一定的优势。 展开更多
关键词 C_(3)h_(6)/N_(2)混合气 分离 浸渍-旋转法 聚多巴胺@聚醚嵌段共聚酰胺
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基于TDLAS的H_(2)S气体材料表面吸附特性研究
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作者 金建新 刘威 +3 位作者 宋振明 朱志辉 田冰 彭志敏 《激光与红外》 CAS CSCD 北大核心 2024年第5期710-717,共8页
在H_(2)S气体浓度在线监测过程中,因其具有粘附性强的特点,容易发生管线吸附,从而导致测量结果存在偏差,尤其在痕量H_(2)S检测过程中表现最为明显,所以开展H_(2)S气体管线材料表面吸附特性研究尤为必要。本文基于可调谐二极管激光吸收... 在H_(2)S气体浓度在线监测过程中,因其具有粘附性强的特点,容易发生管线吸附,从而导致测量结果存在偏差,尤其在痕量H_(2)S检测过程中表现最为明显,所以开展H_(2)S气体管线材料表面吸附特性研究尤为必要。本文基于可调谐二极管激光吸收光谱技术(TDLAS),设计并搭建了一套H_(2)S浓度在线测定系统,并对该系统进行了测量性能检验,在此基础上进行了H_(2)S在不锈钢材料表面常温吸附特性探究。实验结果表明,所搭建H_(2)S浓度在线测定系统具有稳定性强、检测限低和灵敏度高的特点,利用此系统可以实现痕量H_(2)S浓度的在线连续测定。经过一系列探究试验,证明了H_(2)S在不锈钢材料表面存在明显且稳定的吸附作用,得出了H_(2)S在不锈钢材料表面的单位面积吸附量在10^(14)(个/cm^(2))量级。实验结果可以为痕量硫化氢在线精准测量提供一定参考。 展开更多
关键词 TDLaS h_(2)S 测量系统 材料表面 吸附特性
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2-APB通过PKCα/HIF-1α信号通路抑制H_(2)O_(2)诱导的软骨细胞凋亡
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作者 欧阳紫微 董雷 +5 位作者 王琰 程远志 朱仁弟 周仁鹏 赵英杰 胡伟 《安徽医科大学学报》 CAS 北大核心 2024年第7期1150-1156,共7页
目的探讨2-氨基乙氧基苯硼酸(2-APB)对H_(2)O_(2)诱导的软骨细胞凋亡的作用及其机制。方法实验分为Control组、H_(2)O_(2)组、2-APB组和H_(2)O_(2)+2-APB组。CCK-8法检测各组细胞活力;显微镜下观察2-APB对H_(2)O_(2)诱导的软骨细胞形态... 目的探讨2-氨基乙氧基苯硼酸(2-APB)对H_(2)O_(2)诱导的软骨细胞凋亡的作用及其机制。方法实验分为Control组、H_(2)O_(2)组、2-APB组和H_(2)O_(2)+2-APB组。CCK-8法检测各组细胞活力;显微镜下观察2-APB对H_(2)O_(2)诱导的软骨细胞形态变化的影响;TUNEL法和流式细胞术检测软骨细胞凋亡情况;流式细胞术检测脂质活性氧(ROS)水平;Western blot法检测2-APB对H_(2)O_(2)诱导的各组细胞中Cleaved-PARP、p-PKCα和HIF-1α蛋白的表达情况;免疫荧光法检测PKCα抑制剂BIM-Ⅰ对H_(2)O_(2)诱导的各组细胞中HIF-1α的荧光表达情况。结果2-APB对H_(2)O_(2)诱导的软骨细胞凋亡具有抑制作用,且当2-APB浓度为100μmol/L时抑制效果最为显著(F=235.80,P<0.01);2-APB能够抑制H_(2)O_(2)所致软骨细胞凋亡阳性率(F=114.80,P<0.01)以及ROS的水平(F=52.99,P<0.01),并且抑制Cleaved-PARP(F=10.10,P<0.05)、p-PKCα(F=24.56,P<0.05)和HIF-1α(F=6.85,P<0.05)蛋白的表达;PKCα抑制剂BIM-Ⅰ能够抑制H_(2)O_(2)所致HIF-1α荧光强度的增加。结论2-APB可以通过抑制PKCα/HIF-1α通路减少H_(2)O_(2)诱导的软骨细胞凋亡,进而保护软骨细胞。 展开更多
关键词 2-氨基乙氧基苯硼酸 软骨细胞 细胞凋亡 h_(2)O_(2) PKCα/hIF-1α通路
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Fe(Ⅱ)EDTA络合吸收耦合H_(2)-MBfR处理NO效能
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作者 刘婉婷 钱飞跃 +3 位作者 赵俊杰 徐正慧 王建芳 缪润珠 《中国环境科学》 EI CAS CSCD 北大核心 2024年第3期1335-1346,共12页
构建Fe(Ⅱ)EDTA络合吸收耦合H_(2)-MBfR一体化系统,驯化具有同步反硝化及铁还原能力的混合菌种,在维持反应体系稳定反硝化性能的基础上,探究进水Fe(Ⅱ)EDTA浓度、pH值对NO去除效率的影响,分析微生物群落结构.结果表明,Fe(Ⅱ)EDTA络合吸... 构建Fe(Ⅱ)EDTA络合吸收耦合H_(2)-MBfR一体化系统,驯化具有同步反硝化及铁还原能力的混合菌种,在维持反应体系稳定反硝化性能的基础上,探究进水Fe(Ⅱ)EDTA浓度、pH值对NO去除效率的影响,分析微生物群落结构.结果表明,Fe(Ⅱ)EDTA络合吸收耦合H_(2)-MBfR还原一体化系统对NO具有稳定去除效能,最大去除效率为99.50%.提高初始Fe(Ⅱ)EDTA浓度有助于Fe(Ⅱ)EDTA-NO的生成,且体系内的NO平均去除速率随着Fe(Ⅱ)EDTA浓度的提升而提升.在Fe(Ⅱ)EDTA浓度为10mmol/L时,NO最大去除速率达到44.68mg/(m3·h).pH值升高则不利于Fe(Ⅱ)EDTA-NO的生成,控制pH值为6更适合一体化系统运行.微生物群落结构分析发现一体化阶段优势菌门Proteobacteria、Bacteroidetes和Firmicutes,在该反应器中承担着重要的功能和作用,其丰度占比分别为50.35%,16.43%,14.98%. 展开更多
关键词 氢自养膜生物膜反应器(h_(2)-MBfR) 烟气脱硝 络合吸收 影响因素
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HA/H_(2)O_(2)体系对磺胺噻唑降解的机理与效能
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作者 武玮 郑伟杰 +3 位作者 许荣刚 罗从伟 任会学 陈飞勇 《净水技术》 CAS 2024年第6期95-105,共11页
以盐酸羟胺/过氧化氢(HA/H_(2)O_(2))作为研究体系,考察其对于磺胺噻唑(STZ)的降解效能。文章考察了HA初始浓度、H_(2)O_(2)初始浓度、STZ初始浓度、pH、天然有机物(NOM)、阴离子(SO_(4)^(2-)、Cl-和NO_(3)^(-))对STZ降解的影响。结果表... 以盐酸羟胺/过氧化氢(HA/H_(2)O_(2))作为研究体系,考察其对于磺胺噻唑(STZ)的降解效能。文章考察了HA初始浓度、H_(2)O_(2)初始浓度、STZ初始浓度、pH、天然有机物(NOM)、阴离子(SO_(4)^(2-)、Cl-和NO_(3)^(-))对STZ降解的影响。结果表明:在pH值=3.0的条件下,HA/H_(2)O_(2)体系对STZ具有高效的降解效果,当HA的物质的量浓度由2 mmol/L增加到10 mmol/L时,对STZ的去除率从56.06%增加到85.26%;当H_(2)O_(2)的物质的量浓度从2 mmol/L增加到10 mmol/L时,对STZ的去除率从58.96%增加到85.26%,当STZ的物质的量浓度从2μmol/L增加到10μmol/L时,对STZ的去除率从98.72%降低到71.86%。随着pH的增大,STZ的去除率逐渐降低,在pH值>7的条件下对STZ的去除率可以忽略不计。向反应体系中分别投加5 mmol/L的SO_(4)^(2-)和5 mmol/L的NO_(3)^(-)都可以有效促进STZ的降解,而5 mmol/L的Cl^(-)则会抑制STZ的降解。当向体系中投加小于5 mg/L的NOM则对STZ的降解的影响可以忽略不计。测定了体系中共有17种降解产物,并推测STZ通过取代反应、羟基化反应等方式逐步被降解。通过明亮发光杆菌发光值变化分析降解过程中溶液毒性的变化,测定发现STZ降解过程中急性毒性不高。实际水体试验结果表明,HA/H_(2)O_(2)系统对二级出水中的荧光类物质具有较好的降解效果。 展开更多
关键词 盐酸羟胺/过氧化氢(ha/h_(2)O_(2)) 磺胺噻唑(STZ) 氧化降解 产物分析 急性毒性
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基于TDLAS的H_(2)S高温反应特性实验研究
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作者 王嘉琦 田思迪 +3 位作者 高东波 田志伟 彭志敏 杜艳君 《热力发电》 CAS CSCD 北大核心 2024年第2期162-169,共8页
电站锅炉在低NO_(x)燃烧过程中因锅炉内还原性气氛浓度较高,会产生较多H_(2)S气体。针对H_(2)S因具有易燃、强腐蚀性、剧毒性而可能对火电厂造成多种危害的问题,采用可调谐二极管激光吸收光谱(tunable diode laser absorption spectrosc... 电站锅炉在低NO_(x)燃烧过程中因锅炉内还原性气氛浓度较高,会产生较多H_(2)S气体。针对H_(2)S因具有易燃、强腐蚀性、剧毒性而可能对火电厂造成多种危害的问题,采用可调谐二极管激光吸收光谱(tunable diode laser absorption spectroscopy,TDLAS)方法结合多通池和计算机搭建低气体摩尔分数在线测量系统,实现了对混合气体中摩尔分数在10–6量级H_(2)S的精确在线测量,并利用该测量系统进行了H_(2)S高温反应实验,探究实验温度和混合气体中O_(2)摩尔分数对该反应的影响。实验结果展示了压力为80 kPa、O_(2)摩尔分数为0~5%的条件下,H_(2)S开始发生化学反应的温度随O_(2)摩尔分数变化的变化规律,整体而言,混合气体中O_(2)摩尔分数越高,H_(2)S开始发生化学反应的温度越低。实验结果可以为锅炉烟气中H_(2)S的生成、转化和危害控制提供一定数据基础。 展开更多
关键词 TDLaS h_(2)S 在线测量 高温反应 O_(2)摩尔分数
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Surface-modified Ag@Ru-P25 for photocatalytic CO_(2) conversion with high selectivity over CH_(4) formation at the solid–gas interface 被引量:4
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作者 Chaitanya B.Hiragond Sohag Biswas +8 位作者 Niket SPowar Junho Lee Eunhee Gong Hwapyong Kim Hong Soo Kim Jin-Woo Jung Chang-Hee Cho Bryan M.Wong Su-Il In 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期182-196,共15页
Systematic optimization of the photocatalyst and investigation of the role of each component is important to maximizing catalytic activity and comprehending the photocatalytic conversion of CO_(2) reduction to solar f... Systematic optimization of the photocatalyst and investigation of the role of each component is important to maximizing catalytic activity and comprehending the photocatalytic conversion of CO_(2) reduction to solar fuels.A surface-modified Ag@Ru-P25 photocatalyst with H_(2)O_(2) treatment was designed in this study to convert CO_(2) and H_(2)O vapor into highly selective CH4.Ru doping followed by Ag nanoparticles(NPs)cocatalyst deposition on P25(TiO_(2))enhances visible light absorption and charge separation,whereas H_(2)O_(2) treatment modifies the surface of the photocatalyst with hydroxyl(–OH)groups and promotes CO_(2) adsorption.High-resonance transmission electron microscopy,X-ray photoelectron spectroscopy,X-ray absorption near-edge structure,and extended X-ray absorption fine structure techniques were used to analyze the surface and chemical composition of the photocatalyst,while thermogravimetric analysis,CO_(2) adsorption isotherm,and temperature programmed desorption study were performed to examine the significance of H_(2)O_(2) treatment in increasing CO_(2) reduction activity.The optimized Ag1.0@Ru1.0-P25 photocatalyst performed excellent CO_(2) reduction activity into CO,CH4,and C2H6 with a~95%selectivity of CH4,where the activity was~135 times higher than that of pristine TiO_(2)(P25).For the first time,this work explored the effect of H_(2)O_(2) treatment on the photocatalyst that dramatically increases CO_(2) reduction activity. 展开更多
关键词 gas-phase CO_(2) reduction h_(2)O_(2) treatment plasmonic nanoparticles solar fuel photocatalyst surface modification
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H_(2) FPEF和HFA-PEFF评分在我国射血分数保留心力衰竭及射血分数保留心力衰竭合并心房颤动患者中的适用性分析
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作者 贾晓艳 刘离香 +2 位作者 王东伟 马西文 刘永铭 《中国医学科学院学报》 CAS CSCD 北大核心 2024年第2期154-160,共7页
目的分析H_(2) FPEF和HFA-PEFF评分对我国单纯射血分数保留的心力衰竭(HFpEF)和HFpEF合并心房颤动(AF)的诊断价值,并探讨其相关因素。方法本研究为横断面研究,连续纳入2009至2020年兰州大学第一医院老年心血管内科收治的HFpEF患者835例... 目的分析H_(2) FPEF和HFA-PEFF评分对我国单纯射血分数保留的心力衰竭(HFpEF)和HFpEF合并心房颤动(AF)的诊断价值,并探讨其相关因素。方法本研究为横断面研究,连续纳入2009至2020年兰州大学第一医院老年心血管内科收治的HFpEF患者835例,根据是否合并AF分为HFpEF合并AF组(n=267)和单纯HFpEF组(n=568);采用HFA-PEFF和H_(2) FPEF评分进行回顾性诊断,并评估两种评分系统诊断的一致性。选取同期136名年龄、性别分别与观察组频数匹配的健康人作为健康对照组,分别对HFpEF合并AF和单纯HFpEF进行受试者工作特征曲线分析,评估H_(2) FPEF和HFA-PEFF两种评分识别HFpEF合并AF和单纯HFpEF的能力。结果HFpEF合并AF组和单纯HFpEF组HFA-PEFF评分比较差异无统计学意义(P=0.070),但HFpEF合并AF组平均H_(2) FPEF评分和评分≥6分的比例均明显高于单纯HFpEF组(P均<0.001)。受试者工作特征曲线分析显示,HFA-PEFF和H_(2) FPEF评分诊断全部HFpEF患者的效能均较高,受试者工作特征曲线下面积(AUC)分别为0.892和0.922,最佳临界值均为4。HFA-PEFF评分诊断单纯HFpEF和HFpEF合并AF的效能接近,AUC分别为0.899和0.911。H_(2) FPEF评分诊断HFpEF合并AF的效能较高,AUC约为1.000,而诊断单纯HFpEF的价值相对较低,AUC为0.885。结论HFA-PEFF评分在单纯HFpEF和HFpEF合并AF中均具有较高的适应性,但H_(2) FPEF评分可能低估了我国患者的单纯HFpEF,H_(2) FPEF评分在我国单纯HFpEF患者中的适用性有待进一步研究。 展开更多
关键词 射血分数保留的心力衰竭 心房颤动 h_(2)FPEF评分 hFa-PEFF评分
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H_(2)S^(+)在A^(2)A_(1)(v1=1,v2=8,v3=0)激发态的光解动力学
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作者 李洁 王雅玲 +6 位作者 谭玉欣 张宁 王文鑫 胡丽如 袁道福 王兴安 杨学明 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第2期271-278,I0103,共9页
振动激发在分子和离子的光解动力学中有着重要的作用:开展特定振动激发态分子离子的光解离动力学实验研究存在很大挑战,尤其是实现合频振动激发离子的量子态选择的制备.本文利用时间切片离子速度成像技术研究了H_(2)S^(+)离子经A^(2)A_(... 振动激发在分子和离子的光解动力学中有着重要的作用:开展特定振动激发态分子离子的光解离动力学实验研究存在很大挑战,尤其是实现合频振动激发离子的量子态选择的制备.本文利用时间切片离子速度成像技术研究了H_(2)S^(+)离子经A^(2)A_(1)(v1=1,v2=8,v3=0)激发态解离生成S^(+)(4S)和H_(2)的光解动力学.实验结合多光子电离和共振激发技术制备了振动激发的H_(2)S^(+),获得了离子在357.02~358.38nm范围内六个光解波长下产物S^(+)的速度影像.根据实验影像,获得了产物的总平动能谱和不同转动态的角分布各项异性参数特别指出地是在很窄的光解能量范围内,转动产物H_(2)(J=1)和H_(2)(J=3)的分支比出现多次反转,该现象与A^(2)A_(1)态单一振动模式激发的H2S+离子的光解动力学行为有明显不同.该研究表明,合频振动激发的H_(2)S^(+)离子光解动力学中可能存在振动模式之间的协同效应. 展开更多
关键词 h_(2)S^(+)离子 离子速度成像 合频振动模式 光解动力学
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NaF-Na_(3)PO_(4)-H_(2)O体系相图与热力学模型 被引量:1
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作者 常静宇 周桓 +3 位作者 杨洁 郝晴 赵鋆 李杰 《天津科技大学学报》 CAS 2024年第1期30-41,共12页
NaF–Na_(3)PO_(4)–H_(2)O体系是稀土矿物加工的典型盐水体系,开发氟、磷回收工艺需要该体系的相图和热力学模型支持。利用等温溶解平衡法测定了273.15 K、298.15 K、323.15 K和348.15 K的固液相平衡数据,并基于eNRTL模型框架构建了该... NaF–Na_(3)PO_(4)–H_(2)O体系是稀土矿物加工的典型盐水体系,开发氟、磷回收工艺需要该体系的相图和热力学模型支持。利用等温溶解平衡法测定了273.15 K、298.15 K、323.15 K和348.15 K的固液相平衡数据,并基于eNRTL模型框架构建了该体系从最低共熔点到348.15 K的热力学模型。实验结果表明:NaF–Na_(3)PO_(4)–H_(2)O体系存在NaF、Na_(3)PO_(4)·12H_(2)O、Na_(3)PO_(4)·8H_(2)O和复盐NaF·2Na_(3)PO_(4)·19H_(2)O 4个固相物种;其中复盐在各温度均占据三元体系的主要相区,磷酸钠水合物的相区极窄,很难单独成盐,NaF相区相对较大并随温度升高而增大。热力学模型研究较好地表达了NaF–H_(2)O、Na_(3)PO_(4)–H_(2)O体系的多温离子活度系数、溶液渗透系数、二元体系相图,获得了盐水作用参数和6个固相的热力学数据;通过对三元体系多温相图数据的有效表达,获得了盐-盐作用参数和复盐的热力学数据,在此基础上推测了NaF–Na_(3)PO_(4)–H_(2)O体系相图结构,获得了难以实验测定的9个零变量点和9条单变量共饱和线,从而得到了全部固相的平衡相区,并给出了NaF–Na_(3)PO_(4)–H_(2)O体系完整相图,为更复杂体系的热力学表达以及工业应用提供了参考依据。 展开更多
关键词 相平衡 相图 热力学模型 NaF–Na_(3)PO_(4)–h_(2)O
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Global characterization of OsPIP aquaporins reveals that the H_(2)O_(2)transporter OsPIP2;6 increases resistance to rice blast 被引量:1
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作者 Gousi Li Jingluan Han +6 位作者 Chen Yi Hao Luo Yuzhu Wang Fengpin Wang Xiaoyu Wang Letian Chen Yaling Zhang 《The Crop Journal》 SCIE CSCD 2024年第1期102-109,共8页
Plasma membrane intrinsic proteins(PIPs)are conserved plant aquaporins that transport small molecules across the plasma membrane to trigger instant stress responses and maintain cellular homeostasis under biotic and a... Plasma membrane intrinsic proteins(PIPs)are conserved plant aquaporins that transport small molecules across the plasma membrane to trigger instant stress responses and maintain cellular homeostasis under biotic and abiotic stress.To elucidate their roles in plant immunity to pathogen attack,we characterized the expression patterns,subcellular localizations,and H_(2)O_(2)-transport ability of 11 OsPIPs in rice(Oryza sativa),and identified OsPIP2;6 as necessary for rice disease resistance.OsPIP2;6 resides on the plasma membrane and facilitates cytoplasmic import of the immune signaling molecule H_(2)O_(2).Knockout of OsPIP2;6 increases rice susceptibility to Magnaporthe oryzae,indicating a positive function in plant immunity.OsPIP2;6 interacts with OsPIP2;2,which has been reported to increase rice resistance to pathogens via H_(2)O_(2)transport.Our findings suggest that OsPIP2;6 cooperates with OsPIP2;2 as a defense signal transporter complex during plant–pathogen interaction. 展开更多
关键词 aQUaPORIN Plant immunity Rice blast h_(2)O_(2)transport
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Involvement of the ABA-and H_(2)O_(2)-Mediated Ascorbate-Glutathione Cycle in the Drought Stress Responses of Wheat Roots 被引量:1
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作者 Mengyuan Li Zhongye Gao +2 位作者 Lina Jiang Leishan Chen Jianhui Ma 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期329-342,共14页
Abscisic acid(ABA),hydrogen peroxide(H_(2)O_(2)) and ascorbate(AsA)–glutathione(GSH)cycle are widely known for their participation in various stresses.However,the relationship between ABA and H_(2)O_(2) levels and th... Abscisic acid(ABA),hydrogen peroxide(H_(2)O_(2)) and ascorbate(AsA)–glutathione(GSH)cycle are widely known for their participation in various stresses.However,the relationship between ABA and H_(2)O_(2) levels and the AsA–GSH cycle under drought stress in wheat has not been studied.In this study,a hydroponic experiment was conducted in wheat seedlings subjected to 15%polyethylene glycol(PEG)6000–induced dehydration.Drought stress caused the rapid accumulation of endogenous ABA and H_(2)O_(2) and significantly decreased the number of root tips compared with the control.The application of ABA significantly increased the number of root tips,whereas the application of H_(2)O_(2) markedly reduced the number of root tips,compared with that under 15%PEG-6000.In addition,drought stress markedly increased the DHA,GSH and GSSG levels,but decreased the AsA levels,AsA/DHA and GSH/GSSG ratios compared with those in the control.The activities of the four enzymes in the AsA–GSH cycle were also markedly increased under drought stress,including glutathione reductase(GR),ascorbate peroxidase(APX),monodehydroascorbate reductase(MDHAR)and dehydroascorbate reductase(DHAR),compared with those in the control.However,the application of an ABA inhibitor significantly inhibited GR,DHAR and APX activities,whereas the application of an H_(2)O_(2) inhibitor significantly inhibited DHAR and MDHAR activities.Furthermore,the application of ABA inhibitor significantly promoted the increases of H_(2)O_(2) and the application of H_(2)O_(2) inhibitor significantly blocked the increases of ABA,compared with those under 15% PEG-6000.Taken together,the results indicated that ABA and H_(2)O_(2) probably interact under drought stress in wheat;and both of them can mediate drought stress by modulating the enzymes in AsA–GSH cycle,where ABA acts as the main regulator of GR,DHAR,and APX activities,and H_(2)O_(2) acts as the main regulator of DHAR and MDHAR activities. 展开更多
关键词 aBa h_(2)O_(2) asa-GSh cycle drought stress wheat roots
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Eliminating H_(2)O/HF and regulating interphase with bifunctional tolylene-2,4-diisocyanate(TDI)additive for long life Li-ion battery 被引量:2
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作者 Xueyi Zeng Xiang Gao +8 位作者 Peiqi Zhou Haijia Li Xin He Weizhen Fan Chaojun Fan Tianxiang Yang Zhen Ma Xiaoyang Zhao Junmin Nan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期519-528,I0011,共11页
Lithium-ion batteries(LIBs)featuring a Ni-rich cathode exhibit increased specific capacity,but the establishment of a stable interphase through the implementation of a functional electrolyte strategy remains challengi... Lithium-ion batteries(LIBs)featuring a Ni-rich cathode exhibit increased specific capacity,but the establishment of a stable interphase through the implementation of a functional electrolyte strategy remains challenging.Especially when the battery is operated under high temperature,the trace water present in the electrolyte will accelerate the hydrolysis of the electrolyte and the resulting HF will further erode the interphase.In order to enhance the long-term cycling performance of graphite/LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)LIBs,herein,Tolylene-2,4-diisocyanate(TDI)additive containing lone-pair electrons is employed to formulate a novel bifunctional electrolyte aimed at eliminating H_(2)O/HF generated at elevated temperature.After 1000 cycles at 25℃,the battery incorporating the TDI-containing electrolyte exhibits an impressive capacity retention of 94%at 1 C.In contrast,the battery utilizing the blank electrolyte has a lower capacity retention of only 78%.Furthermore,after undergoing 550 cycles at 1 C under45℃,the inclusion of TDI results in a notable enhancement of capacity,increasing it from 68%to 80%.This indicates TDI has a favorable influence on the cycling performance of LIBs,especially at elevated temperatures.The analysis of the film formation mechanism suggests that the lone pair of electrons of the isocyanate group in TDI play a crucial role in inhibiting the generation of H_(2)O and HF,which leads to the formation of a thin and dense interphase.The existence of this interphase is thought to substantially enhance the cycling performance of the LIBs.This work not only improves the performance of graphite/NCM811 batteries at room temperature and high temperature by eliminating H_(2)O/HF but also presents a novel strategy for advancing functional electrolyte development. 展开更多
关键词 Graphite/LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)battery Tolylene-2 4-diisocyanate Long-cycling performance h_(2)O/hF eliminated additive
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A functionalized activated carbon adsorbent prepared from waste amidoxime resin by modifying with H_(3)PO_(4) and ZnCl_(2) and its excellent Cr(Ⅵ)adsorption 被引量:1
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作者 Chunlin He Yun Liu +6 位作者 Mingwei Qi Zunzhang Liu Yuezhou Wei Toyohisa Fujita Guifang Wang Shaojian Ma Wenchao Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期585-598,共14页
With the application of resins in various fields, numerous waste resins that are difficult to treat have been produced. The industrial wastewater containing Cr(Ⅵ) has severely polluted soil and groundwater environmen... With the application of resins in various fields, numerous waste resins that are difficult to treat have been produced. The industrial wastewater containing Cr(Ⅵ) has severely polluted soil and groundwater environments, thereby endangering human health. Therefore, in this paper, a novel functionalized mesoporous adsorbent PPR-Z was synthesized from waste amidoxime resin for adsorbing Cr(Ⅵ). The waste amidoxime resin was first modified with H3PO4 and ZnCl_(2), and subsequently, it was carbonized through slow thermal decomposition. The static adsorption of PPR-Z conforms to the pseudo-second-order kinetic model and Langmuir isotherm, indicating that the Cr(Ⅵ) adsorption by PPR-Z is mostly chemical adsorption and exhibits single-layer adsorption. The saturated adsorption capacity of the adsorbent for Cr(Ⅵ) could reach 255.86 mg/g. The adsorbent could effectively reduce Cr(Ⅵ) to Cr(Ⅲ) and decrease the toxicity of Cr(Ⅵ) during adsorption. PPR-Z exhibited Cr(Ⅵ) selectivity in electroplating wastewater. The main mechanisms involved in the Cr(Ⅵ) adsorption are the chemical reduction of Cr(Ⅵ) into Cr(Ⅲ) and electrostatic and coordination interactions. Preparation of PPR-Z not only solves the problem of waste resin treatment but also effectively controls Cr(Ⅵ) pollution and realizes the concept of “treating waste with waste”. 展开更多
关键词 waste amidoxime resin mesoporous adsorbent h_(3)PO_(4)and ZnCl_(2)processing Cr(VI)adsorption electroplating wastewater
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利用水热二次生长法制备用于H_(2)/CO_(2)分离的KAUST-8膜
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作者 Asad Sharif 王泓博 +2 位作者 鲁金明 杨建华 刘毅 《膜科学与技术》 CAS CSCD 北大核心 2024年第5期90-99,共10页
KAUST-8纳米片比表面积和孔隙率较高、铝金属位点丰富,因此具有出色的二氧化碳吸附能力.在本研究中,采用水热二次生长技术,在粗糙的大孔α-Al_(2)O_(3)载体管上,引入氧化铝和硝酸镍作为前驱体,其中,Al_(2)O_(3)用于控制无机支柱[AlF_(5)... KAUST-8纳米片比表面积和孔隙率较高、铝金属位点丰富,因此具有出色的二氧化碳吸附能力.在本研究中,采用水热二次生长技术,在粗糙的大孔α-Al_(2)O_(3)载体管上,引入氧化铝和硝酸镍作为前驱体,其中,Al_(2)O_(3)用于控制无机支柱[AlF_(5)(H_(2)O)]^(2-)的生长,Ni(NO_(3))_(2)·6H_(2)O用于提高金属前驱体镍源在溶剂中的溶解度,促进Ni(Ⅱ)-吡嗪方格的形成,并与无机柱中心[AlF_(5)(H_(2)O)]^(2-)反应,合成了多晶KAUST-8膜.并进一步探讨了反应物浓度、时间、温度等合成条件以及溶剂对KAUST-8膜性能的影响.优化后的KAUST-8膜的H_(2)渗透率为1.27×10^(-7)mol/(m^(2)·s·Pa)(25℃、0.1 MPa条件下),H_(2)/CO_(2)的理想选择性为19.3. 展开更多
关键词 CO_(2)分离 KaUST-8膜 氟化金属有机框架膜 水热合成 h_(2)纯化
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Investigating the charge transfer mechanism of ZnSe QD/COF S-scheme photocatalyst for H_(2)O_(2) production by using femtosecond transient absorption spectroscopy
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作者 Yanyan Zhao Chunyan Yang +4 位作者 Shumin Zhang Guotai Sun Bicheng Zhu Linxi Wang Jianjun Zhang 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期258-269,共12页
Hydrogen peroxide(H_(2)O_(2))has gained widespread attention as a versatile oxidant and a mild disin-fectant.Here,an electrostatic self-assembly method is applied to couple ZnSe quantum dots(QDs)with a flower-like cov... Hydrogen peroxide(H_(2)O_(2))has gained widespread attention as a versatile oxidant and a mild disin-fectant.Here,an electrostatic self-assembly method is applied to couple ZnSe quantum dots(QDs)with a flower-like covalent organic framework(COF)to form a step-scheme(S-scheme)photocata-lyst for H_(2)O_(2)production.The as-prepared S-scheme photocatalyst exhibits a broad light absorption range with an edge at 810 nm owing to the synergistic effect between the ZnSe QDs and COF.The S-scheme charge-carrier transfer mechanism is validated by performing Fermi level calculations and in-situ X-ray photoelectron and femtosecond transient absorption spectroscopies.Photolumi-nescence,time-resolved photoluminescence,photocurrent response,electrochemical impedance spectroscopy,and electron paramagnetic resonance results show that the S-scheme heterojunction not only promotes charge carrier separation but also boosts the redox ability,resulting in enhanced photocatalytic performance.Remarkably,a 10%-ZnSe QD/COF has excellent photocatalytic H_(2)O_(2)-production activity,and the optimal S-scheme composite with ethanol as the hole scavenger yields a H_(2)O_(2)-production rate of 1895 mol g^(-1)h^(-1).This study presents an example of a high-performance organic/inorganic S-scheme photocatalyst for H_(2)O_(2)production. 展开更多
关键词 ZnSe quantum dot Covalent organic framework S-scheme heterojunction Carrier migration and separation h_(2)O_(2) production
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H_(2)S分压对SA387M Gr.11CL2(H)炼化管道用钢腐蚀行为的影响
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作者 艾芳芳 陈义庆 +4 位作者 王储 刘智勇 钟彬 高鹏 李琳 《压力容器》 北大核心 2024年第8期47-55,共9页
为了探究H_(2)S分压对SA387M Gr.11CL2(H)炼化管道用钢腐蚀行为的影响,采用高压釜进行试验,通过SEM,EDS,XRD和EPMA分析了SA387M Gr.11CL2(H)钢腐蚀产物的形貌、成分和物相。结果表明,随着H_(2)S分压(PH_(2)S)的增加,SA387M Gr.11CL2(H)... 为了探究H_(2)S分压对SA387M Gr.11CL2(H)炼化管道用钢腐蚀行为的影响,采用高压釜进行试验,通过SEM,EDS,XRD和EPMA分析了SA387M Gr.11CL2(H)钢腐蚀产物的形貌、成分和物相。结果表明,随着H_(2)S分压(PH_(2)S)的增加,SA387M Gr.11CL2(H)钢的腐蚀减薄量增大。PH_(2)S≤0.5 MPa时,以全面腐蚀为主;PH_(2)S=1.0 MPa时,钢发生全面腐蚀伴随局部腐蚀,应力促进了局部腐蚀。SA387M Gr.11CL2(H)钢耐硫化物应力腐蚀性能良好。PH_(2)S≤0.5 MPa时,腐蚀产物膜中Cr的化合物和具有保护性的硫铁化合物发挥协同作用,有效阻止介质中Cl-的侵入;PH_(2)S=1.0 MPa时,腐蚀产物膜中Cr的化合物含量少,生成的硫铁化合物不具有保护性。H_(2)S分压影响了腐蚀产物膜的生成;Cr的化合物和硫铁化合物的组成和结构的变化,是导致SA387M Gr.11CL2(H)钢发生全面腐蚀和局部腐蚀的主要原因。 展开更多
关键词 炼化管道用钢 h_(2)S分压 硫化物应力腐蚀 CR元素 硫铁化合物
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Aqueous-phase reforming of hydroxyacetone solution to bio-based H_(2)over supported Pt catalysts
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作者 A.K.K.Vikla K.Koichumanova +1 位作者 Songbo He K.Seshan 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第4期777-788,共12页
Aqueous-phase reforming(APR)is an attractive process to produce bio-based hydrogen from waste biomass streams,during which the catalyst stability is often challenged due to the harsh reaction conditions.In this work,t... Aqueous-phase reforming(APR)is an attractive process to produce bio-based hydrogen from waste biomass streams,during which the catalyst stability is often challenged due to the harsh reaction conditions.In this work,three Pt-based catalysts supported on C,AlO(OH),and ZrO_(2)were investigated for the APR of hydroxyacetone solution in afixed bed reactor at 225℃and 35 bar.Among them,the Pt/C catalyst showed the highest turnover frequency for H_(2)production(TOF of 8.9 molH_(2)molPt^(-1)min^(-1))and the longest catalyst stability.Over the AlO(OH)and ZrO_(2)supported Pt catalysts,the side reactions consuming H_(2),formation of coke,and Pt sintering result in a low H_(2)production and the fast catalyst deactivation.The proposed reaction pathways suggest that a promising APR catalyst should reform all oxygenates in the aqueous phase,minimize the hydrogenation of the oxygenates,maximize the WGS reaction,and inhibit the condensation and coking reactions for maximizing the hydrogen yield and a stable catalytic performance. 展开更多
关键词 aPR hYDROXYaCETONE TOF Bio-based h_(2) Support effect
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