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小鼠^(13)N-NH_(3)·H_(2)O心肌灌注Micro-PET显像中尾静脉注射技术的优化与评估
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作者 李长虹 李强 +4 位作者 石云华 韦顺 李韦微 周洁 付巍 《标记免疫分析与临床》 CAS 2024年第3期539-544,共6页
目的通过自制小鼠尾静脉留置针,为小鼠^(13)N-NH_(3)·H_(2)O心肌灌注显像提供实用、快捷、成功率高的实验工具,并总结归纳出一套流畅、高效的实验流程。方法实验组和对照组分别使用本实验室自制的鼠尾静脉留置针及人外周浅静脉一... 目的通过自制小鼠尾静脉留置针,为小鼠^(13)N-NH_(3)·H_(2)O心肌灌注显像提供实用、快捷、成功率高的实验工具,并总结归纳出一套流畅、高效的实验流程。方法实验组和对照组分别使用本实验室自制的鼠尾静脉留置针及人外周浅静脉一次性使用静脉留置针(洁瑞26G)为小鼠行尾静脉留置针穿刺,经留置针推注^(13)N-NH_(3)·H_(2)O,配合Micro-PET动态采集,记录图像采集的成功率及图像质量并评价两组注射的优缺点。结果两组实验在穿刺成功率、穿刺时间、药物残留量、图像质量及小鼠尾部放射性药物残留量5方面差异均具有统计学意义(P<0.05)。综合比较,自制留置针制作及操作简便、穿刺成功率高、对鼠尾静脉损伤小,且在图像采集成功率及质量方面均占优势。结论自制鼠尾静脉留置针联合优化的实验流程,能显著提高鼠尾静脉穿刺成功率和图像质量,很好地应用于小鼠^(13)N-NH_(3)·H_(2)O心肌灌注Micro-PET显像中。 展开更多
关键词 小鼠 尾静脉注射 留置针 ^^(13)N-Nh_(3)·h_(2)O 心肌灌注 Micro-PET
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(H_(2)O)_(n)^(+)(n=2~5)团簇离子在308 nm处的光解动力学
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作者 赵云肖 胡高明 +2 位作者 李佑卿 陈旸 赵东锋 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第2期279-285,I0103,共8页
本文利用一套高分辨圆柱形低温离子阱速度成像谱仪装置研究了小团簇离子(H_(2)O)_(n)^(+)(n=2-5)在308 nm处的光解动力学.通过记录光解产物碎片质谱和速度影像,发现二聚体水团簇(H_(2)O)_(2)^(+)解离生成H_(3)O^(+)和H_(2)O^(+)光碎片,... 本文利用一套高分辨圆柱形低温离子阱速度成像谱仪装置研究了小团簇离子(H_(2)O)_(n)^(+)(n=2-5)在308 nm处的光解动力学.通过记录光解产物碎片质谱和速度影像,发现二聚体水团簇(H_(2)O)_(2)^(+)解离生成H_(3)O^(+)和H_(2)O^(+)光碎片,表明其同时存在质子转移(H_(3)O^(+)-OH)和半束缚(H_(2)O-OH_(2))+两种构型,水团簇离子(H_(2)O)_(n)^(+)(n=3~5)普遍通过同时丢失OH和H_(2)O部分解离得到H+(H_(2)O)_(n-2,…,1)光碎片,并且(H_(2)O)_(5)^(+)团簇离子有一个仅通过丢失OH的额外通道得到H+(H_(2)O)4.前者表明(H_(2)O)_(n)^(+)(n=3~5)的构型是(H_(2)O)_(n-2)H_(3)O^(+)OH,后者表明在(H_(2)O)_(5)^(+)团簇离子中核H_(3)O^(+)和OH被H_(2)O分开.基于实验影像得到的光碎片各向异性参数为负值并且值较小,表明(H_(2)O)_(n)^(+)(n=2~5)团簇离子在光子吸收后经历垂直电子跃迁,随后缓慢解离,并导致光碎片的高内部激发. 展开更多
关键词 ^(h_(2)O)_(n)^(+)团簇 光解动力学 飞行时间质谱 速度成像
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Dependence of photoelectron-momentum distribution of H_2^+ molecule on orientation angle and laser ellipticity
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作者 Hong-Dan Zhang Si-Qi Zhang +3 位作者 Lei Ji Qi Zhen Jing Guo Xue-Shen Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第5期75-79,共5页
By numerically solving the two-dimensional time-dependent Schr¨odinger equation under the frozen-nuclei approximation, we are able to study the molecular photoelectron-momentum distribution(MPMD) of H^+_2 with di... By numerically solving the two-dimensional time-dependent Schr¨odinger equation under the frozen-nuclei approximation, we are able to study the molecular photoelectron-momentum distribution(MPMD) of H^+_2 with different orientation angles driven by elliptically polarized laser pulse with varying ellipticities. Our numerical results show that the MPMD is sensitive to the orientation angle and the laser ellipticity, which can be explained by the attosecond perturbation ionization theory and the exactly solvable photoionization model. When the ellipticity ε = 0, the final MPMD of x-oriented H^+_2 shows a distinct six-lobe pattern that is different from that with ε = 0.5 and ε = 1. The evolutions of electron wave packet(EWP)and MPMD with x-oriented H^+_2 are presented to interpret this distinct pattern. 展开更多
关键词 ^h2^+ molecule molecular photoelectron-momentum distribution ATTOSECOND perturbation ionization theory
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DFT calculation on relaxation and electronic structure of sulfide minerals surfaces in presence of H_2O molecule 被引量:4
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作者 陈建华 龙贤灏 +2 位作者 赵翠华 康端 郭进 《Journal of Central South University》 SCIE EI CAS 2014年第10期3945-3954,共10页
First-principles calculations are performed to investigate the relaxation and electronic properties of sulfide minerals surfaces(MoS2, Sb2S3, Cu2 S, ZnS, PbS and FeS2) in presence of H2 O molecule. The calculated resu... First-principles calculations are performed to investigate the relaxation and electronic properties of sulfide minerals surfaces(MoS2, Sb2S3, Cu2 S, ZnS, PbS and FeS2) in presence of H2 O molecule. The calculated results show that the structure and electronic properties of sulfide minerals surfaces have been influenced in presence of H2 O molecule. The adsorption of the flotation reagent at the interface of mineral-water would be different from that of mineral surface due to the changes of surface structures and electronic properties caused by H2 O molecule. Hence, the influence of H2 O molecule on the reaction of flotation reagent with sulfide mineral surface will attract more attention. 展开更多
关键词 sulfide minerals surfaces h_2O molecule RELAXATION electronic properties density-functional theory(DFT) calculation
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准南阜康区块煤层后生生物成因H_(2)S的发现与成因机制
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作者 闫佩佩 苏现波 +3 位作者 邹成龙 赵伟仲 汪露飞 伏海蛟 《煤田地质与勘探》 EI CAS CSCD 北大核心 2023年第10期52-61,共10页
随着排采的进行准南东段阜康区块煤层气井产出的煤层气中H_(2)S浓度呈现逐渐增加的趋势,对安全生产构成严重威胁。基于煤层气勘探开发资料,结合实验室厌氧发酵实验,对该区块排采阶段煤层H_(2)S的异常原因进行初步探讨。煤层气勘探阶段... 随着排采的进行准南东段阜康区块煤层气井产出的煤层气中H_(2)S浓度呈现逐渐增加的趋势,对安全生产构成严重威胁。基于煤层气勘探开发资料,结合实验室厌氧发酵实验,对该区块排采阶段煤层H_(2)S的异常原因进行初步探讨。煤层气勘探阶段含气量测试结果表明,煤层气原始气体中H_(2)S含量低,最高仅为2.152×10^(−6);排采初期并未出现H_(2)S浓度异常现象,但随着排采的进行,部分井出现异常,如13号井在排采7 a后H_(2)S含量异常增加,高达700×10^(−6)。灰色关联分析表明,H_(2)S的浓度与煤层气井的产水量和水质密切相关,当地下水的补给带来充足的营养物质供给菌群代谢时,就会促进H_(2)S的产出。由该区煤和排采水作为发酵基液构建的厌氧发酵系统表明,H_(2)S的产量与发酵液中SO_(4)^(2−)含量成反比、与HCO_(3)^(−)含量成正比;CH4的产气高峰滞后于H_(2)S,且累计生成量显著低于H_(2)S,而由该区的煤与蒸馏水作为发酵基液构建的厌氧发酵系统则以产CH4为主,仅生成微量的H_(2)S,说明H_(2)S是硫酸盐还原菌以CH4为电子供体还原SO_(4)^(2−)生成的;发酵液中小分子有机酸含量的不断减少说明硫酸盐还原菌同样利用了有机酸为电子供体还原SO_(4)^(2−)生成H_(2)S。因此,现场生产资料和实验室厌氧发酵结果表明该区H_(2)S是由煤层水中的SO_(4)^(2−)被硫酸盐还原菌还原生成。这种排采阶段生成的生物气与以往人们认为的原生和次生生物气都不相同,将其称为后生生物气,其中的H_(2)S称为后生生物H_(2)S。排采过程中后生生物气的生成进一步说明人工干预下的煤层气生物工程实施的可行性。 展开更多
关键词 准南阜康区块 煤层气井水 硫酸盐还原 ^SO_(4)^(2−) 后生生物成因h_(2)S
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吖啶-苯并咪唑环番化合物在检测H_(2)PO_(4)^(-)中的应用 被引量:1
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作者 董智云 韩喜龙 +1 位作者 王迎进 席福贵 《化学试剂》 CAS 北大核心 2021年第5期692-697,共6页
以一种吖啶-苯并咪唑环番化合物L为荧光传感器,在化合物L的V(乙腈)∶V(水)=95∶5溶液中加入H_(2)PO_(4)^(-)后导致荧光发射峰(E_(m)=426 nm)猝灭,检出限为4.75×10^(-7) mol/L,Job曲线显示化合物L和H_(2)PO_(4)^(-)离子之间以1∶... 以一种吖啶-苯并咪唑环番化合物L为荧光传感器,在化合物L的V(乙腈)∶V(水)=95∶5溶液中加入H_(2)PO_(4)^(-)后导致荧光发射峰(E_(m)=426 nm)猝灭,检出限为4.75×10^(-7) mol/L,Job曲线显示化合物L和H_(2)PO_(4)^(-)离子之间以1∶1化学计量比结合,结合常数为(6.96±0.44)×10^(4) L/mol。在波长为365 nm紫外灯照射下,化合物L发出明显的蓝绿色荧光,而L-H_(2)PO_(4)^(-)配合物呈现较弱的蓝色荧光,可实现固态检测H_(2)PO_(4)^(-)阴离子。DFT计算显示化合物L通过苯并咪唑2位H与H_(2)PO_(4)^(-)离子之间形成了非常强的离子型氢键。 展开更多
关键词 吖啶 环番化合物 苯并咪唑 ^h_(2)PO_(4)^(-) 荧光传感器
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Double open mouse-like terpyridine parts based amphiphilic ionic molecules displaying strengthened chemical adsorption for anticorrosion of copper in sulfuric acid solution
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作者 Yueting Shi Junhai Zhao +3 位作者 Lingli Chen Hongru Li Shengtao Zhang Fang Gao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第5期233-246,共14页
In this study,the benign target double terpyridine parts based amphiphilic ionic molecules(AIMs 1,2)and the reference single terpyridine segment included AIMs(AIMs 3,4)were synthesized through a multi-step method,and ... In this study,the benign target double terpyridine parts based amphiphilic ionic molecules(AIMs 1,2)and the reference single terpyridine segment included AIMs(AIMs 3,4)were synthesized through a multi-step method,and the molecular structures were fully characterized.The excellent anticorrosion of the target AIMs for copper surface in H_(2)SO_(4) solution was demonstrated by the electrochemistry analysis,which was more superior over those of the reference AIMs.The standard adsorption free energy changes of the target AIMs calculated by the adsorption isotherms were lower than -40 kJ·mol^(-1),suggesting an intensified chemical adsorption on metal surface.The molecular modeling and molecular dynamic computation of the studied AIMs were performed,demonstrating that the target AIMs exhibited lower highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps and greater adsorption energies than the reference ones.The chemical adsorption of the AIMs on metal surface was revealed by various spectroscopic methods including scanning electron microscopy,atomic force microscopy,Fourier transform infrared spectroscopy,attenuated total reflection infrared spectroscopy,Raman and X-ray diffraction. 展开更多
关键词 Amphiphilic ionic molecule Adsorption Corrosion Electrochemistry COPPER h_(2)SO_(4)solution
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La(H_(2)O)^(3+)_(10)在蒙脱石(001)表面吸附的密度泛函计算
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作者 姚小辉 黄李金鸿 +3 位作者 黄万抚 曾祥荣 黄彪林 包亚晴 《硅酸盐通报》 CAS 北大核心 2021年第11期3769-3776,共8页
为研究蒙脱石(001)面与水合稀土离子La(H_(2)O)^(3+)_(10)的相互作用对La(H_(2)O)^(3+)_(10)在蒙脱石表面吸附的影响,分别计算了蒙脱石Na-(001)面(存在钠离子的面)和None-(001)面(不存在钠离子的面)与La(H_(2)O)^(3+)_(10)相互作用的吸... 为研究蒙脱石(001)面与水合稀土离子La(H_(2)O)^(3+)_(10)的相互作用对La(H_(2)O)^(3+)_(10)在蒙脱石表面吸附的影响,分别计算了蒙脱石Na-(001)面(存在钠离子的面)和None-(001)面(不存在钠离子的面)与La(H_(2)O)^(3+)_(10)相互作用的吸附能,距离最近的各原子的分态密度、电子转移以及作用强度。结果表明,存在Na离子的Na-(001)面吸附能更大,La(H_(2)O)^(3+)_(10)在Na-(001)表面能更稳定的吸附。La(H_(2)O)^(3+)_(10)的O_(w)(水合水分子中的氧原子)和Na-(001)表面的Na、None-(001)表面O_(f)(表层暴露出来的氧原子)和La(H_(2)O)^(3+)_(10)的H_(w)(水合水分子中的氢原子)存在一定的相互作用,La原子转移到Na-(001)表面的电荷(0.44 e)大于None-(001)表面(0.16 e)。Na—O_(w)作用强度大于O_(f)—H_(w),La(H_(2)O)^(3+)_(10)在蒙脱石Na-(001)面的吸附强度比在None-(001)面更强,可推断层间Na离子增强了La(H_(2)O)^(3+)_(10)在蒙脱石(001)表面的吸附强度。 展开更多
关键词 蒙脱石 表面吸附 ^La(h_(2)O)^(3+)_(10) 吸附能 电子转移 吸附强度
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Optical spectroscopy study of damage evolution in 6H-SiC by H_(2)^(+)implantation
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作者 Yong Wang Qing Liao +5 位作者 Ming Liu Peng-Fei Zheng Xinyu Gao Zheng Jia Shuai Xu Bing-Sheng Li 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第5期75-80,共6页
Lattice defects induced by ion implantation into SiC have been widely investigated in the decades by various techniques.One of the non-destructive techniques suitable to study the lattice defects in SiC is the optical... Lattice defects induced by ion implantation into SiC have been widely investigated in the decades by various techniques.One of the non-destructive techniques suitable to study the lattice defects in SiC is the optical characterization.In this work,confocal Raman scattering spectroscopy and photoluminescence spectrum have been used to study the effects of 134-keV H_(2)^(+)implantation and thermal treatment in the microstructure of 6H-SiC single crystal.The radiation-induced changes in the microstructure were assessed by integrating Raman-scattering peaks intensity and considering the asymmetry of Raman-scattering peaks.The integrated intensities of Raman scattering spectroscopy and photoluminescence spectrum decrease with increasing the fluence.The recovery of the optical intensities depends on the combination of the implantation temperature and the annealing temperature with the thermal treatment from 700℃to 1100℃.The different characterizations of Raman scattering spectroscopy and photoluminescence spectrum are compared and discussed in this study. 展开更多
关键词 SIC ^h_(2)^(+)implantation Raman scattering spectroscopy photoluminescence spectrum
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H_(2)S分子负脉冲流光放电等离子体解离分析
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作者 张淼 张连水 《河北大学学报(自然科学版)》 CAS 北大核心 2021年第2期133-139,共7页
采用荧光发射光谱和荧光时间分辨光谱,对H_(2)S分子进行了脉冲流光放电激发解离相关实验研究.将所得400~800 nm荧光谱线归属为S_(2)、S^(-2)、H、SH等活性粒子的发光.结果表明,H_(2)S气体脉冲流光放电等离子体中的主要活性粒子是H_(2)S*... 采用荧光发射光谱和荧光时间分辨光谱,对H_(2)S分子进行了脉冲流光放电激发解离相关实验研究.将所得400~800 nm荧光谱线归属为S_(2)、S^(-2)、H、SH等活性粒子的发光.结果表明,H_(2)S气体脉冲流光放电等离子体中的主要活性粒子是H_(2)S*、S_(2)、S^(-2)、H、SH,且时间分辨光谱测量结果表明H和SH基荧光信号几乎同时出现,由此确定H_(2)S气体脉冲流光等离子体放电主要激发解离通道为H_(2)S+e*→H_(2)S*+e→H*+SH*. 展开更多
关键词 h_(2)S分子 流光放电等离子体 激发解离
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羰基锝硝基咪唑化合物^99Tc^m(CO)3-MNLS的标记和生物学评价
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作者 甘红梅 刘晶莹 +2 位作者 査智豪 乔晋萍 朱霖 《核化学与放射化学》 CAS CSCD 北大核心 2011年第5期302-307,共6页
本文采用直接标记法在水相中将羰基锝中间体[99 Tcm(CO)3(H2O)3]+与含磷酸基团的硝基咪唑衍生物2-(2-甲基-5-硝基咪唑-1-基)乙基磷酸盐(2-(2-methyl-5-nitro-1H-imidazol-1-yl)ethyl dihydrogen phos-phate,MNLS)配位得到99 Tcm(CO)3-M... 本文采用直接标记法在水相中将羰基锝中间体[99 Tcm(CO)3(H2O)3]+与含磷酸基团的硝基咪唑衍生物2-(2-甲基-5-硝基咪唑-1-基)乙基磷酸盐(2-(2-methyl-5-nitro-1H-imidazol-1-yl)ethyl dihydrogen phos-phate,MNLS)配位得到99 Tcm(CO)3-MNLS配合物;研究了99 Tcm(CO)3-MNLS的最佳标记条件、理化性质及其在荷EMT-6肿瘤小鼠体内的生物分布。结果表明,当MNLS质量为10mg、pH=4.0~8.0、80℃下反应15min时,99 Tcm(CO)3-MNLS配合物放化纯度大于99%。电泳试验结果提示,99 Tcm(CO)3-MNLS为水溶性的电中性配合物,具有良好的体外稳定性。动物分布试验显示,99 Tcm(CO)3-MNLS在荷EMT-6肿瘤小鼠体内有较高的肿瘤摄取值,且滞留较好;此外,99 Tcm(CO)3-MNLS较99 Tcm-MNLS在骨中的摄取值明显降低。以上结果为研发新型乏氧组织显像剂提供了重要参考。 展开更多
关键词 ^[^99Tc^m(CO)_3(h_2O)_3]^+ MNLS ^^99Tc^m(CO)_3-MNLS 理化性质 生物分布
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Decomposition pathway and stabilization of ether-based electrolytes in the discharge process of Li-O_(2) battery 被引量:1
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作者 Xiao Liu Xiaosheng Song +5 位作者 Qi Zhang Xuebing Zhu Qing Han Zewen Liu Peng Zhang Yong Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第6期516-523,I0014,共9页
Ether-based electrolytes with relatively high stability are widely used in Li-O_(2) batteries (LOBs) with high energy density.However,they are still prone to be attacked by reactive oxygen species.Understanding the de... Ether-based electrolytes with relatively high stability are widely used in Li-O_(2) batteries (LOBs) with high energy density.However,they are still prone to be attacked by reactive oxygen species.Understanding the degradation chemistry of ether-based solvent induced by reactive oxygen species is significant importance toward selection of stable electrolytes for LOBs.Herein,we demonstrate that a great amount of H_(2) gas evolves on the Li anode during the long-term discharge process of LOBs,which is due to the electrolyte decomposition at the oxygen cathode.By coupling with in-situ and ex-situ characterization techniques,it is demonstrated that O_(2)^(-) induces the H-abstraction of tetraethylene glycol dimethyl ether(TEGDME) to produce a large amount of H_(2)O at cathode,and this H_(2)O migrates to Li anode and produce H_(2) gas.Based on the established experiments and spectra,a possible decomposition pathway of TEGDME caused by O_(2)^(-)at the discharge process is proposed.And moreover,three types of strategies are discussed to inhibit the decomposition of ether-based electrolytes,which should be highly important for the fundamental and technical advancement for LOBs. 展开更多
关键词 Lithium-oxygen batteries Ether-based electrolytes Discharge process Decomposition pathway h_(2)O molecule hydrogen evolution
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离子液体化石墨烯量子点及其对H_(2)PO_(4)^(-)的荧光增强识别
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作者 马文辉 问婧 +6 位作者 赵宝茹 王健恺 黄鑫 王悦 杜小雨 张永 王丽艳 《分析试验室》 CAS CSCD 北大核心 2021年第12期1425-1429,共5页
通过表面修饰法制备了离子液体化石墨烯量子点(GQDs-IL),采用透射电子显微镜(TEM)、原子力显微镜(AFM)、傅里叶变换红外光谱仪(FTIR)、X射线光电子能谱仪(XPS)等对其形貌和结构进行了表征。结果表明离子液体与GQDs通过酰胺键相连,GQDs-I... 通过表面修饰法制备了离子液体化石墨烯量子点(GQDs-IL),采用透射电子显微镜(TEM)、原子力显微镜(AFM)、傅里叶变换红外光谱仪(FTIR)、X射线光电子能谱仪(XPS)等对其形貌和结构进行了表征。结果表明离子液体与GQDs通过酰胺键相连,GQDs-IL的粒径分布均匀,平均粒径为4.6 nm。光谱性能表明,GQDs-IL在二甲基甲酰胺(DMF)溶液中,在常见阴离子(F^(-),Cl^(-),Br^(-),I^(-),AcO^(-),HSO^(-),H_(2)PO_(4)^(-),CN^(-))中能够专一性地识别H_(2)PO_(4)^(-),滴加H_(2)PO_(4)^(-)后引起荧光增强3.61倍,检出限为3.2 nmol/L,其它阴离子的存在并未干扰GQDs-IL对H_(2)PO_(4)^(-)的检测。 展开更多
关键词 石墨烯量子点 离子液体 ^h_(2)PO_(4)^(-)荧光增强
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联产混合电解水策略实现节能电化学制氢的最新进展
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作者 Diab khalafallah 张运祥 +2 位作者 王昊 Jong-Min Lee 张勤芳 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第12期44-115,共72页
随着全球能源需求增长和环境污染加剧,发展可持续能源减少对化石燃料(如石油、天然气和煤炭等)的消耗成为实现人类社会可持续发展的关键.氢能因其能量密度高、燃烧无污染、应用形式多样被认为是最理想的替代能源.电解水制氢包括阴极析... 随着全球能源需求增长和环境污染加剧,发展可持续能源减少对化石燃料(如石油、天然气和煤炭等)的消耗成为实现人类社会可持续发展的关键.氢能因其能量密度高、燃烧无污染、应用形式多样被认为是最理想的替代能源.电解水制氢包括阴极析氢反应(HER)和阳极析氧反应(OER),具有绿色环保、生产灵活和纯度高等特点,是理想的绿色生产技术之一.然而,阳极电解水产氧反应动力学缓慢,导致阴极的产氢效率低.此外,在电解水过程中,会产生高氧化性的过氧化氢(H_(2)O_(2)),降低电解水膜的寿命,阻碍电解水技术的实际应用.因此,亟待开发新型高效、稳定且具有高附加值的电解水催化剂.目前,电化学整体水分解(OWS)制氢技术存在安全风险、投资回报低、阳极OER动力学慢和电能消耗大等问题,将阳极氧化反应与混合电解水(HWE)装置中的HER相结合,借助热力学较好的电氧化反应取代缓慢的传统OER反应协同产氢,可以有效克服传统电解水的产率不足,解决污染排放和生物质回收问题.本文综述了协同电催化用于联产氢气和低能耗、高法拉第效率高价值产品的催化剂结构设计,揭示不同协同电催化系统的催化途径和意义,以实现更高效、零碳排放的目标.首先,介绍了HWE系统的发展现状,重点关注各种富氢物质的协同电解,例如酒精、生物质衍生物、葡萄糖和在阳极形成的高附加值化学品.与传统阳极OER工艺相比,有机/生物质底物小分子的OER表现出较低的热力学需求,降低产氢能耗.随后,详细介绍了基于阴极HER和阳极OER协同电解反应、协同催化HWE高效电极/电催化剂的合理设计,以实现高催化活性、高选择性和良好的电化学稳定性.重点讨论了新型电极/电催化剂设计、活性改进以及结构-催化活性关系提升的合成策略.再后,讨论了基于有机/生物质小分子协同HWE系统电催化的代表性研究进展和突破,强调了其在促进可持续低压制氢方面的重要作用,并回顾了近年来HWE的研究突破,同时,对一些可行性分析和机理探索进行比较,为制氢提供了新的研究方向.最后,提出了协同电催化制氢面临的挑战并展望未来的研究方向.综上,大多数电催化剂存在催化活性低、稳定性差等问题,要实现可持续、经济高效和清洁的产氢技术,仍有很多方面需要进一步的深入研究.本文综述了高效多功能HWE系统发展现状和催化剂结构设计,为电解水制氢和高附加值产品的节能联产提供一定的参考. 展开更多
关键词 阳极氧化反应 小有机分子 混合电解水 节能制氢 附加值产品 过渡金属 协调效应 活性位 催化活性 稳定性
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An in-situ NH_(4)^(+)-etched strategy for anchoring atomic Mo site on ZnIn_(2)S_(4) hierarchical nanotubes for superior hydrogen photocatalysis 被引量:1
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作者 Yuguang Chao Weiyu Zhang +6 位作者 Peng Zhou Hui Chen Shiyu Lu Menggang Li Qinghua Zhang Lin Gu Shaojun Guo 《Science China Chemistry》 SCIE EI CSCD 2021年第10期1716-1722,共7页
Atomic sites co-catalyst (ASC) on photocatalytic materials possesses an attractive prospect to promote charge carrier separation and tune surface reaction kinetics,yet the synthesis of earth-abundant ASC under low tem... Atomic sites co-catalyst (ASC) on photocatalytic materials possesses an attractive prospect to promote charge carrier separation and tune surface reaction kinetics,yet the synthesis of earth-abundant ASC under low temperature remains a great challenge.Here,a novel in-situ NH_(4)^(+)-etched strategy to anchor atomic Mo sites on ZnIn_(2)S_(4)hierarchical nanotubes (HNTs) with abundant mesopores under mild conditions for promoting charge carrier separation and enhancing light multi-reflections is developed for efficient photocatalytic H_(2) evolution.Density functional theory calculations and linear sweep voltammetry demonstrate that the well-defined Mo-S_(2)O_(1) sites with distinctive coordination configuration and electronic property contribute to the enhanced separation of photo-generated charge carriers and reduced Gibbs free energy for H_(2) evolution.Consequently,the well-defined MoSA-ZIS HNTs present an excellent photocatalytic activity with a rate of 29.9μmol h^(-1)(5.98 mmol g^(-1)h^(-1)),which is 7.3 times higher than that of ZnIn_(2)S_(4)nanosheets (NSs),to be among the best ZnIn_(2)S_(4)-based photocatalysts.The present strategy breaks the high-temperature limitation of conventional top-down thermal dissociation/emitting approach for anchoring non-noble metal atomic sites on catalyst support. 展开更多
关键词 in-situ ^Nh_(4)^(+)-etched hierarchical nanotubes Mo single atoms photocatalytic h_(2)evolution
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Keggin-type polycationic AlO_(4)Al_(12)(OH)_(24)H_(2)O_(12)^(7+)intercalated MoO_(3)composites for methyl orange adsorption
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作者 Qian Wang Hongrui Tian +5 位作者 Zhong Zhang Tianyi Dang Wanyu Zhang Jie Wang Ying Lu Shuxia Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第5期2617-2620,共4页
Molybdenum trioxide(MoO_(3))can be employed as an excellent host for intercalation due to its 2D lay-ered structure that connected by van der Waals interactions.Herein,a series of polyoxometalate-based MoO_(3) composi... Molybdenum trioxide(MoO_(3))can be employed as an excellent host for intercalation due to its 2D lay-ered structure that connected by van der Waals interactions.Herein,a series of polyoxometalate-based MoO_(3) composites(Al_(13)@MoO_(3))were successfully prepared by interpolating the Keggin-type polycationic AlO_(4)Al_(12)(OH)_(24)H_(2)O_(12)^(7+)(Al_(13))into MoO_(3)gallery.These composites can be applied to rapidly adsorb the anionic dye methyl orange(MO)through strong electrostatic interactions lead to compact and sta-ble gathering in the surrounding of the numerous charged Al_(13).Adsorption behaviors of composites with the different amount of Al_(13) were determined,these results revealed that Al_(13)-3.34%@MoO_(3)exhibited the most remarkable adsorption capacity.More importantly,the composite maintains superior adsorption capacity for five consecutive adsorption/desorption cycles,suggesting that Al_(13)@MoO_(3)can be an efficient and durable adsorbent. 展开更多
关键词 MoO_(3) Keggin-type polycationic ^AlO_(4)Al_(12)(Oh)_(24)h_(2)O_(12)^(7+) Intercalation ADSORPTION Methyl orange dye
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原位ATR-IR光谱实时研究DKDP的结晶过程
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作者 刘发付 张丛 +4 位作者 郭建斌 张武 曹剑武 张海波 徐明霞 《人工晶体学报》 CAS 北大核心 2022年第3期404-410,433,共8页
采用全反模式的红外(ATR-IR)光谱实时研究了不同氘含量KH_(2-x)D_(x)PO_(4)(DKDP)晶体的结晶过程,其中DKDP溶液氘含量范围为0到99%。通过υ_(1)()PO_(4))和υ_(3)(PO_(4))振动表征了DKDP结晶溶液中(H_(2)PO_(4)^(-))_(1-x)(D_(2)PO_(4)^... 采用全反模式的红外(ATR-IR)光谱实时研究了不同氘含量KH_(2-x)D_(x)PO_(4)(DKDP)晶体的结晶过程,其中DKDP溶液氘含量范围为0到99%。通过υ_(1)()PO_(4))和υ_(3)(PO_(4))振动表征了DKDP结晶溶液中(H_(2)PO_(4)^(-))_(1-x)(D_(2)PO_(4)^(-))_(x)离子基团浓度的变化。υ_(1)(PO_(4))振动强度的变化和υ_(3)(PO_(4))振动宽度的变化说明生长溶液中的(H_(2)PO_(4)^(-))_(1-x)(D_(2)PO_(4)^(-))_(x)离子浓度随着测试时间延长而不断增大。同时,δ(P—O…H/D—O—P)振动峰的形成说明DKDP晶体的生长基元为(H_(2)PO_(4)^(-))_(n-x)(D_(2)PO_(4)^(-))_(x)离子团簇。波数在1448 cm^(-1)到1653 cm^(-1)范围内H—O—H和D—O—D振动强度的变化解释了DKDP晶体在结晶过程中氘含量分布不均的现象。 展开更多
关键词 DKDP单晶 结晶过程 ATR-IR光谱 ^(h_(2)PO_(4)^(-))_(n-x)(D_(2)PO_(4)^(-))_(x)团簇 氘含量 生长基元
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A Fluorescent Chemosensor for Dihydrogen Phosphate Ion Based on 2-[2-Hydroxy-4-(diethylamino)phenyl]-1Himidazo[4,5-b]phenazine-Fe^(3+)Ensemble
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作者 Taibao Wei Guiyuan Wu +3 位作者 Bingbing Shi Qi Lin Hong Yao Youming Zhang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2014年第12期1238-1244,共7页
A long wavelength emission fluorescent(612 nm)chemosensor with high selectivity for H_(2)PO_(4)^(−)ions was designed and synthesized according to the excited state intramolecular proton transfer(ESIPT).The sensor can ... A long wavelength emission fluorescent(612 nm)chemosensor with high selectivity for H_(2)PO_(4)^(−)ions was designed and synthesized according to the excited state intramolecular proton transfer(ESIPT).The sensor can exist in two tautomeric forms(‘keto’and‘enol’)in the presence of Fe^(3+)ion,Fe^(3+)may bind with the‘keto’form of the sensor.Furthermore,the in situ generated GY-Fe^(3+)ensemble could recover the quenched fluorescence upon the addition of H_(2)PO_(4)^(−)anion resulting in an off-on-type sensing with a detection limit of micromolar range in the same medium,and other anions,including F^(−),Cl^(−),Br^(−),I^(−),AcO^(−),HSO^(−)_(4),ClO^(−)_(4)and CN−had nearly no influence on the probing behavior.The test strips based on 2-[2-hydroxy-4-(diethylamino)phenyl]-1H-imidazo[4,5-b]phenazine and Fe^(3+)metal complex(GY-Fe^(3+))were fabricated,which could act as convenient and efficient H_(2)PO_(4)^(−)test kits. 展开更多
关键词 long wavelength fluorescent ^Fe^(3+)ion ^h_(2)PO_(4)^(−) 1h-imidazo[4 5-b]phenazine
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CBF/CBV maps in normal volunteers studied with ^(15)O PET:a possible index of cerebral perfusion pressure 被引量:2
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作者 Tadashi Watabe Eku Shimosegawa +3 位作者 Hiroki Kato Kayako Isohashi Mana Ishibashi Jun Hatazawa 《Neuroscience Bulletin》 SCIE CAS CSCD 2014年第5期857-862,共6页
Local cerebral perfusion pressure (CPP) is a primary factor controlling cerebral circulation and previous studies have indicated that the ratio of cerebral blood flow (CBF) to cerebral blood volume (CBV) can be ... Local cerebral perfusion pressure (CPP) is a primary factor controlling cerebral circulation and previous studies have indicated that the ratio of cerebral blood flow (CBF) to cerebral blood volume (CBV) can be used as an index of the local CPP. In this study, we investigated whether the CBF/CBV ratio differs among different brain structures under physiological conditions, by means of (15)O positron emission tomography. Nine healthy volunteers (5 men and 4 women; mean age, 47.0 ± 1.2 years) were studied by H2(15)O bolus injection for CBF measurement and by C(15)O inhalation for CBV measurement. The CBF/CBV ratio maps were created by dividing the CBF images by the CBV images after anatomical normalization. Regions of interest were placed on the CBF/CBV maps and comparing the regions. The mean CBF/ CBV ratio was highest in the cerebellum (19.3 + 5.2/ min), followed by the putamen (18.2 ± 3.9), pons (16.4 ±4.6), thalamus (14.5:1: 3.3), cerebral cortices (13.2 ±2.4), and centrum semiovale (1115 ± 2.1). The cerebellum and putamen showed significantly higher CBF/CBV ratios than the cerebral cortices and centrum semiovale. We created maps of the CBF/ CBV ratio in normal volunteers and demonstrated higher CBF/CBV ratios in the cerebellum and putamen than in the cerebral cortices and deep cerebral white matter. The CBF/CBV may reflect the local CPP and should be studied in hemodynamicallycompromised patients and in patients with risk factors for small-artery diseases of the brain. Keywords: cerebral perfusion pressure; cerebra blood flow; cerebral blood volume; H2(15)O; C(15)O 展开更多
关键词 cerebral perfusion pressure cerebral blood flow cerebral blood volume ^h_2^(15)O ^C^(15)O
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Chloroplast ROS and stress signaling 被引量:7
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作者 Mengping Li Chanhong Kim 《Plant Communications》 SCIE 2022年第1期100-114,共15页
Chloroplasts overproduce reactive oxygen species(ROS)under unfavorable environmental conditions,and these ROS are implicated in both signaling and oxidative damage.There is mounting evidence for their roles in transla... Chloroplasts overproduce reactive oxygen species(ROS)under unfavorable environmental conditions,and these ROS are implicated in both signaling and oxidative damage.There is mounting evidence for their roles in translating environmental fluctuations into distinct physiological responses,but their targets,signaling cascades,and mutualism and antagonism with other stress signaling cascades and within ROS signaling remain poorly understood.Great efforts made in recent years have shed new light on chloroplast ROS-directed plant stress responses,from ROS perception to plant responses,in conditional mutants of Arabidopsis thaliana or under various stress conditions.Some articles have also reported the mechanisms underlying the complexity of ROS signaling pathways,with an emphasis on spatiotemporal regulation.ROS and oxidative modification of affected target proteins appear to induce retrograde signaling pathways to maintain chloroplast protein quality control and signaling at a whole-cell level using stress hormones.This review focuses on these seemingly interconnected chloroplast-to-nucleus retrograde signaling pathways initiated by ROS and ROS-modified target molecules.We also discuss future directions in chloroplast stress research to pave the way for discovering new signaling molecules and identifying intersectional signaling components that interact in multiple chloroplast signaling pathways. 展开更多
关键词 ROS ^^(1)O_(2) h_(2)O_(2) OXIDATION operational retrograde signaling PROTEOSTASIS
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