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Analysis of pressure response at an observation well against pressure build-up by early stage of CO_(2)geological storage project
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作者 Qiang Sun Kyuro Sasaki +3 位作者 Qinxi Dong Zhenni Ye Hui Wang Huan Sun 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期470-482,共13页
To ensure a safe and stable CO_(2)storage,pressure responses at an observation well are expected to be an important and useful field monitoring item to estimate the CO_(2)storage behaviors and the aquifer parameters d... To ensure a safe and stable CO_(2)storage,pressure responses at an observation well are expected to be an important and useful field monitoring item to estimate the CO_(2)storage behaviors and the aquifer parameters during and after injecting CO_(2),because it can detect whether the injected CO_(2)leaks to the ground surface or the bottom of the sea.In this study,pressure responses were simulated to present design factors such as well location and pressure transmitter of the observation well.Numerical simulations on the pressure response and the time-delay from pressure build-up after CO_(2)injection were conducted by considering aquifer parameters and distance from the CO_(2)injection well to an observation well.The measurement resolution of a pressure transmitter installed in the observation well was presented based on numerical simulation results of the pressure response against pressure build-up at the injection well and CO_(2)plume front propagations.Furthermore,the pressure response at an observation well was estimated by comparing the numerical simulation results with the curve of CO_(2)saturation and relative permeability.It was also suggested that the analytical solution can be used for the analysis of the pressure response tendency using pressure build-up and dimensionless parameters of hydraulic diffusivity.Thus,a criterion was established for selecting a pressure transducer installed at an observation well to monitor the pressure responses with sufficient accuracy and resolution,considering the distance from the injection well and the pressure build-up at the injection well,for future carbon capture and storage(CCS)projects. 展开更多
关键词 CO_(2)storage Saline aquifer Observation well Pressure response CO_(2)saturation
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Acupoint catgut-embedding therapy ameliorates DNCB-induced atopic dermatitis in BALB/c mice by regulating Th2 type immune response and reducing infiltration of CD4^(+)and CD8^(+)cells
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作者 Cheng Qin Xiang-Yi Kong +4 位作者 Fang Wang Jin Xu Zhuo Zhang Xue-Song Yang Jian-Zhou Ye 《Traditional Medicine Research》 2024年第9期14-20,共7页
Background:This study aimed to assess how acupoint catgut-embedding therapy influences Th2-type immune response and the infiltration of CD4^(+)and CD8^(+)cells in DNCB-induced atopic dermatitis in BALB/c mice.It also ... Background:This study aimed to assess how acupoint catgut-embedding therapy influences Th2-type immune response and the infiltration of CD4^(+)and CD8^(+)cells in DNCB-induced atopic dermatitis in BALB/c mice.It also conducted an initial examination of the underlying molecular mechanisms.Methods:Seventy-two mice were randomly divided into four groups:normal control,DNCB-induced atopic dermatitis model(AD),AD with acupoint catgut-embedding treatment(ADA),and AD with sham-acupoint catgut-embedding treatment.After DNCB challenge to induce AD,the ADA group received acupoint catgut-embedding therapy treatment at Zusanli(ST 36)and Quchi(LI 11)acupoints every other week from day 8.Mice in the AD with sham-acupoint catgut-embedding treatment group underwent the same procedure as the ADA group but without catgut implantation.Severity was assessed using SCORAD on treatment days 1,10,and 20.On day 18,nine mice per group were euthanized,and the remaining on day 28.Histopathological changes were observed using hematoxylin-eosin and immunohistochemistry staining.TNF-α,IL-4,IL-6,and IL-13 levels were analyzed by ELISA,and GATA3 and STAT6 protein levels by western blot.Results:After 20 days of acupoint catgut-embedding therapy treatment,mice showed reduced dermatitis scores compared to DNCB-induced AD-like mice.Significant decreases occurred in serum IL-4,IL-6,IL-13,and TNF-αlevels.Skin analysis revealed marked reductions in CD4^(+)and CD8^(+)cell infiltration,as well as GATA3 and STAT6 protein levels.Conclusion:Acupoint catgut-embedding therapy may effectively alleviate atopic dermatitis by suppressing Th2 immune responses via the STAT6-GATA3 pathway and reducing CD4^(+)and CD8^(+)T cell infiltration in skin lesions. 展开更多
关键词 atopic dermatitis acupoint catgut-embedding therapy Th2 type immune response
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Humoral Response and Tolerance of Vaccination against SARS-CoV-2 in Adults Senegalese Patients Undergoing Hemodialysis: A Multicenter Prospective Study
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作者 Lot Nehemie Motoula Latou Moustapha Mbow +3 位作者 Modou Ndongo Gnagna Faye Gora Lo Sidy Mohamed Seck 《Open Journal of Nephrology》 2024年第1期70-80,共11页
Introduction: Following the COVID-19 pandemic, vaccination has been proposed in several countries as the main preventive measure despite very limited data, particularly in dialysis patients. We conducted this study to... Introduction: Following the COVID-19 pandemic, vaccination has been proposed in several countries as the main preventive measure despite very limited data, particularly in dialysis patients. We conducted this study to assess the immunological response to vaccination in Senegalese hemodialysis patients. Patients and Methods: We conducted a prospective study, in two dialysis centers in Dakar from March 30<sup>th</sup> to August 30<sup>th</sup>, 2021 including patients on hemodialysis for >6 months, vaccinated against SARS-CoV-2 according to the vaccination schedule recommended by WHO. A vaccine response was considered positive when seroconversion was observed after one dose of vaccine. The clinical efficacy of immunization was defined as the absence of new COVID-19 infection in patients who received a complete vaccination. Results: Among the 81 patients included in the study, 7.4% had anti-Spike IgM antibodies before their first vaccination. Seroprevalence of IgM antibodies was 38.3% one month after the first vaccine dose (at M1) and 8.6% one month after the second dose (at M4). Anti-Spike IgG antibodies were present in 40.3% of patients before vaccination, in 90.1% at M1, and in 59.7% at M4. Among patients previously infected with SARS-CoV-2, 10.2% had IgM antibodies at M0, 31.6% at M1, and 10.5% at M4 post-vaccination. Similarly, seroprevalences of IgG antibodies in this subgroup were 31.5%, 61.3%, and 50.0% respectively at M0, M1, and M4 post-vaccination. A comparison of seroconversion rates between M0 and M4 showed significant differences only for IgG in COVID-19 naive patients. Mean duration in dialysis and the existence of previous COVID-19 infection were associated with patients’ vaccinal response after the two doses. Age, gender and the use of immunosuppressive treatment did not influence post-vaccinal antibody production. Conclusion: Vaccination against COVID-19 in Senegalese hemodialysis patients induced a low seroconversion rate but it was well tolerated. Moreover, the induced protection was neither strong nor durable, particularly in patients with longer duration in dialysis. 展开更多
关键词 SARS-Cov2 Vaccination Humoral response TOLERANCE HEMODIALYSIS Senegal
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Analysis of genotype differences of rice response to low Zn^(2+) activity and some morphological characteristics 被引量:5
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作者 WANG Renmin, Dept of Agro YANG Xiao’e and YANG Yuai, Dept of Agri Chemistry, ZheJiang Agri Univ, Hangzhou 310029, China 《Chinese Rice Research Newsletter》 1998年第3期11-12,共2页
Zinc deficiency is one of the most widespreadmicro-nutritional disorder for rice. To solve the problem, screening Zn-efficient cultivars isan available method and understanding geno-
关键词 Analysis of genotype differences of rice response to low zn activity and some morphological characteristics root
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MoO_(2)/ZnS复合材料改性隔膜实现锂硫电池稳定的高倍率性能
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作者 许占位 郭隆华 +5 位作者 任宇川 赵家棋 李嘉胤 李亮 马维鹏 张科 《陕西科技大学学报》 北大核心 2024年第6期112-118,共7页
锂硫电池由于其高能量密度、低成本效益被认为是最有前途的下一代电池体系之一.然而多硫化物的穿梭效应大幅降低了锂硫电池的循环稳定性和寿命,严重阻碍其实际应用.无机金属化合物材料改性的隔膜不仅能抑制多硫化锂(LiPS)的穿梭效应,其... 锂硫电池由于其高能量密度、低成本效益被认为是最有前途的下一代电池体系之一.然而多硫化物的穿梭效应大幅降低了锂硫电池的循环稳定性和寿命,严重阻碍其实际应用.无机金属化合物材料改性的隔膜不仅能抑制多硫化锂(LiPS)的穿梭效应,其部分特殊的晶面还能加速多硫化物的氧化还原反应动力学.本文在罗盘状ZnS表面原位生长球状的MoO_(2),制备MoO_(2)/ZnS复合材料.MoO_(2)对多硫化物有着较强的吸附作用,ZnS有着良好的电导率,两者的复合可加速电子传导效率和氧化还原速率.以所制备的MoO_(2)/ZnS作为隔膜改性材料,锂硫电池在5 C的大电流密度下,经过1000次循环后仍可以保持690 mAh g^(-1)的放电比容量,平均每圈的容量衰减率仅为0.014%,表现出优异的循环性能和倍率性能. 展开更多
关键词 MoO_(2) znS 复合材料 穿梭效应 隔膜改性
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Response of seedlings of different tree species to elevated CO_2 in Changbai Mountain 被引量:1
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作者 王淼 李秋荣 +1 位作者 代力民 姬兰柱 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期112-116,共5页
Eco-physiological responses of seedlings of eight species, Pinus koraiensis, Picea koraiensis, Larix olgensis, Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica and Acer mono from broadlea... Eco-physiological responses of seedlings of eight species, Pinus koraiensis, Picea koraiensis, Larix olgensis, Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica and Acer mono from broadleaved/Korean pine forest, to elevated CO2 were studied by using open-top chambers under natural sunlight in Changbai Mountain, China in two growing seasons (1998-1999). Two concentrations of CO2 were designed: elevated CO2 (700 祄olmol-1) and ambient CO2 (400 祄olmol-1). The study results showed that the height growth of the tree seedlings grown at elevated CO2 increased by about 10%-40% compared to those grown at ambient CO2. And the water using efficiency of seedlings also followed the same tendency. However, the responses of seedlings in transpiration and chlorophyll content to elevated CO2 varied with tree species. The broad-leaf tree species were more sensitive to the elevated CO2 than conifer tree species. All seedlings showed a photosynthetic acclimation to long-term elevated CO2. 展开更多
关键词 Elevated CO_2 Eco-physiological response Changbai Mountain
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胺功能化的铜催化剂:氢键介导的电化学CO_(2)还原为C_(2)产物以及优越的可充电Zn-CO_(2)电池性能
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作者 项东 李坤振 +3 位作者 苗康华 龙冉 熊宇杰 康雄武 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第8期43-46,共4页
有机分子功能化是一种有前景的策略,用于调控电化学CO_(2)还原反应(eCO_(2)RR)的C_(2+)产物选择性和活性。然而,我们对于电化学CO_(2)还原调控机制的分子水平理解仍然不够清晰。在本文中,我们成功制备了铜纳米颗粒,并使用一系列胺类衍生... 有机分子功能化是一种有前景的策略,用于调控电化学CO_(2)还原反应(eCO_(2)RR)的C_(2+)产物选择性和活性。然而,我们对于电化学CO_(2)还原调控机制的分子水平理解仍然不够清晰。在本文中,我们成功制备了铜纳米颗粒,并使用一系列胺类衍生物(如十六胺(HAD)、N-甲基十六胺(N-MHDA)、十六烷基二甲胺(HDDMA)和十六酰胺(PMM))对其进行功能化,以系统地研究胺表面活性剂分子结构对eCO_(2)RR选择性和活性的影响。结果表明,HDA的功能化可以将C_(2)产物和C_(2)H_(4)的法拉第效率(FE)提高至73.5%和46.4%,并且在−0.9 V vs.RHE(可逆氢电极)电位下,C_(2)产物的分电流密度为131.4 mA·cm^(−2)。理论研究发现,HDA通过与CO_(2)和eCO_(2)RR中间体之间的氢键相互作用,富集了^(*)CO_(2)、^(*)CO和其他反应中间体,降低了CO―CHO耦合反应的动力学能垒,从而促进了eCO_(2)RR向C_(2)产物的转化。当胺基的H原子被甲基取代后,氢键相互作用减弱,竞争的析氢反应加剧。PMM通过Cu―O键与Cu表面发生键合,而不是通过Cu―N键,导致Cu-PMM更倾向于产乙醇。原位拉曼光谱显示,在Cu-HDA表面,CO主要吸附在Cu的顶位吸附位点上,与在Cu表面上的桥式吸附不同,这可能是因为前者表面对CO的富集引发了CO的吸附构型变化。HDA功能化还提高了Cu催化剂的表面pH。基于Cu-HDA组装的可充电Zn-CO_(2)电池在放电电流密度为16 mA∙cm^(−2)时,最大功率密度为6.48 mW∙cm^(−2),并具有长达60 h的良好充放电稳定性。本研究的重点在于通过在分子水平上调节Cu基材料的CO_(2)RR活性和选择性,促进CO_(2)-C_(2)的转化,这可能为提高C_(2)产物的产率提供新的见解。 展开更多
关键词 二氧化碳还原 CO―CHO耦合 有机分子功能化 原位拉曼 C_(2)产物 zn-CO_(2)电池
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腐蚀产物中Zn_(5)(OH)_(8)Cl_(2)对纯Zn腐蚀行为的影响 被引量:1
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作者 杨元成 王友彬 +4 位作者 赵晋玮 周佳顺 冯济强 高峰 韦悦周 《表面技术》 EI CAS CSCD 北大核心 2024年第4期98-109,151,共13页
目的探究纯Zn腐蚀产物中碱式氯化锌(Zn_(5)(OH)_(8)Cl_(2),ZHC)对其腐蚀防护性能的影响以及腐蚀防护机理。方法通过原位生长法在纯Zn表面制备一层ZHC膜。通过X射线光电子能谱仪(XPS)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)和能谱仪(ED... 目的探究纯Zn腐蚀产物中碱式氯化锌(Zn_(5)(OH)_(8)Cl_(2),ZHC)对其腐蚀防护性能的影响以及腐蚀防护机理。方法通过原位生长法在纯Zn表面制备一层ZHC膜。通过X射线光电子能谱仪(XPS)、X射线衍射仪(XRD)、扫描电子显微镜(SEM)和能谱仪(EDS),分析了样品的物相组成和微观形貌。通过电化学阻抗谱(EIS)和动电位极化曲线(Tafel),评估了ZHC膜对纯Zn腐蚀防护性能的影响。结果纯Zn表面先形成了一层致密细小的ZHC纳米片,铺满整个纯Zn表面后,在第一层ZHC上形成第二层较大尺寸的ZHC纳米片。预制备的ZHC膜可以使纯Zn的腐蚀电流密度从78.23μA/cm^(2)降低到2.08μA/cm^(2),腐蚀电位从‒1.050V(vs.SCE)提升到‒0.998V(vs.SCE),并且随着ZHC制备时间的增加,阴极斜率(βc)逐渐增大,这表明ZHC可以有效阻碍电荷转移,抑制阴极的氧还原,减缓纯Zn的腐蚀速率,对Zn基体的腐蚀起到防护作用。在浸泡腐蚀过程中,ZHC可以抑制HZ的生成,减少絮状腐蚀产物的生成。在短期浸泡过程中,纯Zn的阻抗值随着预制备ZHC的增加而逐渐增大,这是因为生成的腐蚀产物填补ZHC纳米片的空隙,使腐蚀产物膜致密,ZHC膜对Zn基体能起到较好的防护作用。在长期浸泡过程中,ZHC/Zn的阻抗值下降,这是因为ZHC膜破裂,提供了新的腐蚀通道,导致ZHC膜对纯Zn的防护作用下降。结论ZHC膜可以减缓纯Zn的腐蚀速率。对比纯Zn和ZHC/Zn在浸泡过程中的腐蚀行为可知,在短期浸泡过程中,随着预制备ZHC的增加,对纯Zn的防护性能逐渐提高;在长期浸泡腐蚀过程中,ZHC膜对纯Zn腐蚀的防护作用逐渐下降。 展开更多
关键词 腐蚀产物 zn_(5)(OH)_(8)Cl_(2) zn 原位生长 腐蚀防护
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Response of seedlings of different tree species to elevated CO2 in Changbai Mountain 被引量:1
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作者 王淼 李秋荣 +1 位作者 代力民 姬兰柱 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期112-116,185,共页
Eco-physiological responses of seedlings of eight species, Pinus koraiensis, Picea koraiensis, Larix olgensis, Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica and Acer mono from broadlea... Eco-physiological responses of seedlings of eight species, Pinus koraiensis, Picea koraiensis, Larix olgensis, Populus ussuriensis, Betula platyphylla, Tilia amurensis, Traxinus mandshurica and Acer mono from broadleaved/Korean pine forest, to elevated CO2 were studied by using open-top chambers under natural sunlight in Changbai Mountain, China in two growing seasons (1998-1999). Two concentrations of CO2 were designed: elevated CO2 (700 祄olmol-1) and ambient CO2 (400 祄olmol-1). The study results showed that the height growth of the tree seedlings grown at elevated CO2 increased by about 10%-40% compared to those grown at ambient CO2. And the water using efficiency of seedlings also followed the same tendency. However, the responses of seedlings in transpiration and chlorophyll content to elevated CO2 varied with tree species. The broad-leaf tree species were more sensitive to the elevated CO2 than conifer tree species. All seedlings showed a photosynthetic acclimation to long-term elevated CO2. 展开更多
关键词 Elevated CO2 Eco-physiological response Changbai Mountain
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Differences in Light Response Curve and CO_2 Response Curve of Korla Fragrant Pear Trees in Different Training Systems 被引量:2
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作者 江振斌 廖康 +5 位作者 曼苏尔.那斯尔 牛莹莹 庞洪翔 孙琪 徐乐 章世奎 《Agricultural Science & Technology》 CAS 2016年第8期1762-1766,共5页
[Objective] This study was conducted to evaluate three training systems for Korla fragrant pear trees by comparing the characteristic parameters of light response curve and CO2 response curve, and to provide some theo... [Objective] This study was conducted to evaluate three training systems for Korla fragrant pear trees by comparing the characteristic parameters of light response curve and CO2 response curve, and to provide some theoretical basis for improving the pruning techniques of Korla fragrant pear trees. [Method] The light response curve and CO2 response curve of the trees trained to three systems were measured by LI-6400 portable photosynthesis system. The SPAD value was measured using SPAD-502 chlorophyll meter, and specific leaf weight was calculated, to evaluate the effects of the three training systems. [Result] The CO2 response curves of the three training systems were basically in agreement with their light response curves, but there were some differences in their characteristic parameters. Among the three training systems, the maximum net photosynthetic rate, apparent quantum yield and light compensation point of espalier trained trees were the highest, while their light saturation point was the lowest. The CO2 saturation point of delayed-open central leader trained trees and open center trained trees were 1 752 and 1 665 μmol/mol, both of which were much higher than that of espalier trained trees. In addition, the carboxylation efficiency and photorespiration rate of espalier trained trees were both higher than those of delayed-open central leader trained trees and open center trained trees, while the CO2 compensation point of espalier trained trees was the lowest. The leaf SPAD value of espalier trained trees was the largest, followed by that of open center trained trees, and the leaf SPAD value of delayed-open central leader trained trees was the smallest. In addition, the leaf area and specific leaf weight of espalier trained trees were both the highest, followed by those of open center trained trees. [Conclusion] Among the training systems for Korla fragrant pear trees, the espalier training system had better ability to capture light, higher photosynthetic productivity and strongest adaptability to light environment, and open center training system takes the second place. On the contrary, delayed-open central leader training system has the weakest adaptability to light environment, but it can adapt to a higher CO2 concentration. In summary, for the training of Korla fragrant pear trees, espalier training system, which has the highest theoretical yield, is the best among the three training systems, and delayed-open central leader training system is the worst. 展开更多
关键词 Korla fragrant pear Training system Light response curve CO2 response curve
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Zn/ZSM-5催化剂中Zn物种与CO_(2)和正丁烷耦合反应间相关性研究
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作者 孙旭科 刘荣升 +4 位作者 范改丽 刘昱含 叶芳秀 于政锡 刘中民 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第6期154-163,共10页
随着全球温室气体排放的持续增长,二氧化碳(CO_(2))的高效转化与利用已成为应对气候变化、推动可持续发展的重要途径之一.在本课题组的前期研究中,以正丁烷为模型化合物,成功实现了H-ZSM-5分子筛催化CO_(2)与正丁烷发生耦合反应.实验还... 随着全球温室气体排放的持续增长,二氧化碳(CO_(2))的高效转化与利用已成为应对气候变化、推动可持续发展的重要途径之一.在本课题组的前期研究中,以正丁烷为模型化合物,成功实现了H-ZSM-5分子筛催化CO_(2)与正丁烷发生耦合反应.实验还发现,通过对H-ZSM-5进行Zn改性,可以显著提高其催化性能,这为CO_(2)的高效转化和利用提供了新的研究方向.然而,目前关于Zn-ZSM-5催化剂中Zn物种的具体存在状态及其与耦合反应性能之间的关系尚不明确,这限制了高效催化剂的进一步设计.因此,深入探究Zn物种在Zn-ZSM-5催化剂中的存在状态及其与催化性能之间的关联机制,从而设计和开发更高效的CO₂转化催化剂已成为当务之急.本文通过紫外-可见光漫反射光谱、X-射线光电子能谱和1H魔角旋转-核磁共振等多种技术系统地表征了Zn-ZSM-5分子筛中酸性中心和Zn物种存在状态的演变过程,讨论了Zn物种活性中心与耦合反应之间的构-效关系,阐明了耦合反应的机理.研究表明,Zn-ZSM-5分子筛中Zn物种主要以ZnO团簇、Zn-OH^(+)和(Zn-O-Zn)^(2+)的形式存在,且其含量随Zn负载量的变化而改变.其中,ZnO团簇及(Zn-O-Zn)^(2+)物种的含量随Zn负载量的增加而上升,而Zn-OH^(+)物种含量则先上升后下降,这是由于部分Zn-OH^(+)物种转化为(Zn-O-Zn)^(2+)物种.在CO_(2)与正丁烷的耦合反应中,正丁烷的转化受到Brønsted酸位点的减少、Zn活性位点的形成以及粗晶ZnO物种的堆积等多种因素的影响.Zn-OH^(+)物种是主要的CO_(2)催化转化活性中心,而芳烃的生成则主要受Zn-OH^(+)和(Zn-O-Zn)^(2+)物种的影响.Zn-OH^(+)和(Zn-O-Zn)^(2+)物种均具有较强的脱氢性能,可通过脱氢路径促进芳烃的生成.Zn5%-ZSM-5(Zn负载量为5 wt%)样品表现出最优的催化性能:正丁烷转化率为94.71%,CO_(2)转化率为30.43%,芳烃选择性为53.71%.原位实验进一步证实了内酯、羧酸和不饱和醛酮等含氧化合物作为中间体的存在.基于上述研究,我们提出了Zn-ZSM-5上CO_(2)和正丁烷耦合的反应机理,主要包括以下三条反应路径:(1)在Zn-OH^(+)物种的催化作用下,正丁烷和CO_(2)首先被耦合活化形成内酯,随后经过一系列反应形成羧酸、酸酐和其他含氧化合物,最终通过复杂的反应生成芳烃.(2)部分CO_(2)在Zn-OH^(+)物种的催化下,通过逆水煤气变换(RWGS)反应以及与烃类化合物的干重整反应生成CO.这些CO随后在Zn-OH^(+)物种的催化下与烯烃发生耦合反应,最终生成芳烃产物.(3)正丁烷在Zn-OH^(+)和(Zn-O-Zn)^(2+)物种的催化下,发生脱氢和异构化反应产生烯烃.部分烯烃可通过与CO耦合或烯烃发生聚合、环化、脱氢等过程生成芳烃产物.综上所述,本文深入探讨了CO_(2)与正丁烷在Zn-ZSM-5催化剂上的耦合反应机制.通过系统研究,建立了催化剂中Zn物种与催化性能之间的构-效关系,并提出了耦合反应的具体路径.本文不仅有助于深入理解Zn-ZSM-5的催化作用机制,而且对于未来设计和开发更高效的催化体系具有重要的参考价值. 展开更多
关键词 耦合反应 CO_(2)利用 锌的引入 zn-OH+ (zn-O-zn)^(2+) ZSM-5
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Zn^(2+)和TiO_(2)合金化过程中不同成分占比对薄膜结构和光催化性能的影响
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作者 肖文悦 董小硕 +4 位作者 买买提热夏提·买买提 牛娜娜 李国栋 朱泽涛 毕杰昊 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第18期121-130,共10页
使用溶胶-凝胶法在单晶硅衬底上制备一批不同Zn^(2+)成分调节的TiO_(2)薄膜,观测Zn^(2+)和TiO_(2)合金化过程中光学和光催化性能的变化.X射线衍射光谱仪用于观测在合金化过程中薄膜的晶体结构变化并追踪ZnTiO_(3)化合物的形成.扫描电子... 使用溶胶-凝胶法在单晶硅衬底上制备一批不同Zn^(2+)成分调节的TiO_(2)薄膜,观测Zn^(2+)和TiO_(2)合金化过程中光学和光催化性能的变化.X射线衍射光谱仪用于观测在合金化过程中薄膜的晶体结构变化并追踪ZnTiO_(3)化合物的形成.扫描电子显微镜、原子力显微镜用于观测合金化过程中因TiO_(2)晶格对Zn^(2+)溶解度有限而导致薄膜表面出现大量孔洞的现象.X射线光电子能谱和光学带隙用于观测Zn^(2+)与TiO_(2)合金化过程中电子结构层面的变化.最后,通过降解亚甲基蓝(MB)溶液,表明少量Zn^(2+)掺杂完全溶解在TiO_(2)中,并破坏TiO_(2)结晶质量.在Zn^(2+)的成分占比继续提高至15%的过程中,XPS峰形拟合结果验证了TiO_(2)对Zn^(2+)的溶解度有限,导致薄膜出现大量孔洞结构,薄膜的活性比表面积得以提升,同时Zn^(2+)可以有效地捕获光生e^(-)/h^(+).为了继续观察Zn^(2+)浓度对TiO_(2)的影响,将Zn^(2+)的浓度提升至40%,观察Zn^(2+)与TiO_(2)合金化过程中的现象.表明化合物ZnTiO_(3)的出现可以充当e^(-)/h^(+)的复合中心以及TiO_(2).占比的大幅下降导致合金化之后的薄膜光催化效率逐渐下降. 展开更多
关键词 TiO_(2) zn^(2+) 光催化 带隙 表面
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Zn^(2+)掺杂硫化物/氢氧化物异质结构的性能
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作者 李涛 柳伟 +1 位作者 邵琛琛 李清萍 《电池》 CAS 北大核心 2024年第3期297-302,共6页
为提升硫化物的倍率性能和循环稳定性,采用两步电沉积法制备过渡金属硫化物/氢氧化物异质结构复合电极。在碳布上电沉积镍层,改良活性物质与碳布的接触活性;在硫代乙酰胺中添加Zn(NO3)2·7H_(2)O,制备Zn^(2+)掺杂的过渡金属硫化物/... 为提升硫化物的倍率性能和循环稳定性,采用两步电沉积法制备过渡金属硫化物/氢氧化物异质结构复合电极。在碳布上电沉积镍层,改良活性物质与碳布的接触活性;在硫代乙酰胺中添加Zn(NO3)2·7H_(2)O,制备Zn^(2+)掺杂的过渡金属硫化物/氢氧化物异质结构(NCS-Zn-2)。NCS-Zn-2在1 A/g电流下,比电容达到2 703 F/g,在150 A/g高电流下的比电容是1 A/g的40.8%,具有较好的倍率性能。NCS-Zn-2与活性炭组装的工作电压为1.6 V高电压水系非对称超级电容器,在794 W/kg的比功率下,具有79.9 W·h/kg的比能量,以20 A/g电流在0~1.6 V循环20 000次,电容保持率为98.7%。 展开更多
关键词 超级电容器 zn2+掺杂 氢氧化物 硫化物 电化学性能
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草地早熟禾Phosphate Starvation Response 2基因的克隆及表达分析 被引量:1
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作者 齐欣 李春月 +5 位作者 刘本松 刘博 刘宇恒 邸浩洋 赵迪 金忠民 《草地学报》 CAS CSCD 北大核心 2022年第1期29-37,共9页
磷饥饿响应(Phosphate starvation response PHR2)家族基因在植物磷(Pi)信号调节网络中发挥重要指示作用。为了解该基因在逆境胁迫中的反应机制,本研究从草地早熟禾(Poa pratensis L.)中克隆了PHR2基因,对其进行生物信息学和基因表达模... 磷饥饿响应(Phosphate starvation response PHR2)家族基因在植物磷(Pi)信号调节网络中发挥重要指示作用。为了解该基因在逆境胁迫中的反应机制,本研究从草地早熟禾(Poa pratensis L.)中克隆了PHR2基因,对其进行生物信息学和基因表达模式分析,并分析PHR2基因在草地早熟禾逆境胁迫中的作用。结果表明:草地早熟禾PHR2属于MYB-CC型转录因子,与节节麦氨基酸序列高度同源,该基因主要定位在细胞核。PHR2基因在草地早熟禾的根、茎、叶、穗中均有表达,其中根和穗中表达高于茎和叶;低磷诱导叶中PHR2基因表达低于适磷下该基因表达;干旱胁迫抑制该基因在根、叶的表达,但根与叶的转录调控模式存在差异。本研究为探究PHR家族基因在逆境胁迫中的功能提供一定的理论依据。 展开更多
关键词 草地早熟禾 磷胁迫 干旱胁迫 Phosphate Starvation response 2 转录因子
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Relationship Between Ca^(2+) and Plant Ethylene Response 被引量:1
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作者 张艳萍 朱本忠 罗云波 《Acta Botanica Sinica》 CSCD 2002年第4期422-426,共5页
The relationship between Ca 2+ and ethylene response was investigated through analyzing the effect of Ca 2+ on the response to ethylene in etiolated tomato (Lycopersicon esculentum Mill cv. Lichun) seedling grow... The relationship between Ca 2+ and ethylene response was investigated through analyzing the effect of Ca 2+ on the response to ethylene in etiolated tomato (Lycopersicon esculentum Mill cv. Lichun) seedling grown in darkness. When the etiolated tomato seedlings were treated with different concentrations of Ca 2+, the 'triple response' phenotype, ethylene production, the expression of ethylene receptor gene NEVER-RIPE (NR) and the content of cytosolic CaM were determined. With the concentration of Ca 2+ in the culture medium increasing from 0 mmol/L to 3.8 mmol/L, the 'triple response' phenotype of etiolated tomato seedling was correspondingly strengthened; meanwhile the ethylene production, the amount of NR gene expression and the concentration of CaM increased respectively. However, when the concentration of Ca 2+ was increased from 3.8 mmol/L to 10 mmol/L, the phenotype of 'triple response', ethylene production, NR gene expression, and the CaM content didn't increase further, but decreased consequently. The results indicated that the effect of Ca 2+ on the ethylene triple response in etiolated tomato seedling was relevant to ethylene biosynthesis and ethylene receptor gene expression which were influenced by applied Ca 2+, and these effects might be mediated through the change of CaM concentration in plant cell. 展开更多
关键词 Ca 2+ triple response ethylene signal transduction CAM
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Zn-Pt/ZSM-5催化CO_(2)辅助丙烷脱氢的密度泛函理论研究
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作者 屈姝良 樊华华 +2 位作者 聂小娃 丁凡舒 郭新闻 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2024年第2期392-403,共12页
通过密度泛函理论(DFT)计算研究了Zn-Pt/ZSM-5催化丙烷脱氢的反应机理,筛选出最优能量途径。研究发现丙烷在Zn-Lewis和Pt-Lewis酸位点上具有不同的反应路径和限速步骤。Bader电荷计算结果表明,丙烷分子吸附后,[Zn-O-Pt]^(2+)活性位点中P... 通过密度泛函理论(DFT)计算研究了Zn-Pt/ZSM-5催化丙烷脱氢的反应机理,筛选出最优能量途径。研究发现丙烷在Zn-Lewis和Pt-Lewis酸位点上具有不同的反应路径和限速步骤。Bader电荷计算结果表明,丙烷分子吸附后,[Zn-O-Pt]^(2+)活性位点中Pt上的电子密度增加,有利于丙烷活化,Pt位点对H的吸引能力更强,导致Pt—H键断裂生成H_(2)需要克服较高能垒。Pt的引入改变了Zn/ZSM-5的电子性质,影响其催化剂性能。在反应体系中引入CO_(2)改变了丙烷脱氢反应路径,降低了限速步骤能垒,促进反应正向进行。 展开更多
关键词 丙烷脱氢 zn-Pt/ZSM-5 CO_(2)辅助 反应机理 密度泛函理论
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工艺参数对Zn-TiO_(2)复合镀层性能的影响
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作者 雷思哲 翟晓霞 +2 位作者 阮乐 覃冬丽 姜吉琼 《电镀与精饰》 CAS 北大核心 2024年第11期17-22,共6页
采用电沉积法在氯化物体系获得了Zn-TiO_(2)复合镀层,研究了颗粒添加量、电流密度和机械搅拌速度对镀层厚度和耐蚀性的影响,对工艺优化后的镀层进行了形貌和元素分布表征。结果表明:在TiO_(2)添加量为10 g/L、电流密度2 A/dm^(2)、搅拌... 采用电沉积法在氯化物体系获得了Zn-TiO_(2)复合镀层,研究了颗粒添加量、电流密度和机械搅拌速度对镀层厚度和耐蚀性的影响,对工艺优化后的镀层进行了形貌和元素分布表征。结果表明:在TiO_(2)添加量为10 g/L、电流密度2 A/dm^(2)、搅拌速度为150 r/min的沉积条件下,获得的镀层厚度可达8.3μm,腐蚀电流最小为2.983×10^(-4) A;TiO_(2)颗粒成功共沉积到镀层当中,其质量分数为4.6%;镀层中Zn呈层状堆积分布,TiO_(2)颗粒分布在Zn层交界处。 展开更多
关键词 氯化物体系 zn-TiO_(2)复合镀层 耐蚀性 厚度
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负载型ZnCl_(2)/AC催化剂用于乙二醇氢氯化反应的研究
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作者 赵萌达 郭豹 +2 位作者 李文松 刘继东 吕建华 《现代化工》 CAS CSCD 北大核心 2024年第10期186-191,共6页
采用湿浸渍法制备了ZnCl_(2)/AC(活性炭)催化剂并用于乙二醇氢氯化反应合成2-氯乙醇,通过XRD、FT-IR、Py-IR和N_(2)等温吸附-脱附等手段对催化剂进行表征,考察了ZnCl_(2)负载量对AC的物化性质和催化活性的影响。结果表明,负载ZnCl_(2)后... 采用湿浸渍法制备了ZnCl_(2)/AC(活性炭)催化剂并用于乙二醇氢氯化反应合成2-氯乙醇,通过XRD、FT-IR、Py-IR和N_(2)等温吸附-脱附等手段对催化剂进行表征,考察了ZnCl_(2)负载量对AC的物化性质和催化活性的影响。结果表明,负载ZnCl_(2)后,AC上的Lewis酸位点数量显著增加,催化活性得到显著增强。在温度为220℃、LHSV为1 h^(-1)、n(HCl)/n(EG)为2∶1时,10%ZnCl_(2)/AC催化剂表现出最佳催化性能,乙二醇转化率和2-氯乙醇选择性分别为88.26%和93.57%。 展开更多
关键词 2-氯乙醇 乙二醇 氢氯化反应 锌基催化剂 固定床反应器
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Recent Advances in Aqueous Zn||MnO_(2)Batteries 被引量:1
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作者 Chuan Li Rong Zhang +3 位作者 Huilin Cui Yanbo Wang Guojin Liang Chunyi Zhi 《Transactions of Tianjin University》 EI CAS 2024年第1期27-39,共13页
Recently,rechargeable aqueous zinc-based batteries using manganese oxide as the cathode(e.g.,MnO_(2))have gained attention due to their inherent safety,environmental friendliness,and low cost.Despite their potential,a... Recently,rechargeable aqueous zinc-based batteries using manganese oxide as the cathode(e.g.,MnO_(2))have gained attention due to their inherent safety,environmental friendliness,and low cost.Despite their potential,achieving high energy density in Zn||MnO_(2)batteries remains challenging,highlighting the need to understand the electrochemical reaction mechanisms underlying these batteries more deeply and optimize battery components,including electrodes and electrolytes.This review comprehensively summarizes the latest advancements for understanding the electrochemistry reaction mechanisms and designing electrodes and electrolytes for Zn||MnO_(2)batteries in mildly and strongly acidic environments.Furthermore,we highlight the key challenges hindering the extensive application of Zn||MnO_(2)batteries,including high-voltage requirements and areal capacity,and propose innovative solutions to overcome these challenges.We suggest that MnO_(2)/Mn^(2+)conversion in neutral electrolytes is a crucial aspect that needs to be addressed to achieve high-performance Zn||MnO_(2)batteries.These approaches could lead to breakthroughs in the future development of Zn||MnO_(2)batteries,off ering a more sustainable,costeff ective,and high-performance alternative to traditional batteries. 展开更多
关键词 Aqueous zn||MnO_(2)batteries Zinc-ion batteries Zinc batteries MnO_(2)
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Plasma-assisted aerogel interface engineering enables uniform Zn^(2+)flux and fast desolvation kinetics toward zinc metal batteries 被引量:1
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作者 Zijian Xu Zhenhai Shi +7 位作者 Zhan Chang Fan Feng Zhuanyi Liu Dongkun Chu Jianguo Ren Zi-Feng Ma Suli Chen Tianxi Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期29-38,I0002,共11页
The poor reversibility of Zn anodes induced by dendrite growth,surface passivation,and corrosion,severely hinders the practical applicability of Zn metal batteries.To address these issues,a plasmaassisted aerogel(PAG)... The poor reversibility of Zn anodes induced by dendrite growth,surface passivation,and corrosion,severely hinders the practical applicability of Zn metal batteries.To address these issues,a plasmaassisted aerogel(PAG)interface engineering was proposed as efficient ion transport modulator that can simultaneously regulate uniform Zn^(2+)flux and desolvation behavior during battery operation.The PAG with ordered mesopores acted as an ion sieve to homogenize Zn deposition and accelerate Zn^(2+)flux,which is favorable for corrosion resistance and dendrite suppression.Importantly,the plasma-assisted aerogel with abundant hydrophilic groups can facilitate the desolvation kinetics of Zn^(2+)due to the multiple hydrogen-bonding interaction with the activated water molecules,thus accelerating the Zn^(2+)migration kinetics.Consequently,the Zn/Zn cell assembled with PAG-modified separator demonstrates stable plating and stripping behavior(over 1400 h at 1 mA cm^(-2))and high Coulombic efficiency(99.8%at1 mA cm^(-2)after 1100 cycles),and the Zn‖MnO_(2)full cell shows excellent long-term cycling stability and maintains a high capacity of 154.9 mA h g^(-1)after 1000 cycles at 1 A g^(-1).This study provides a feasible approach for the large-scale fabrication of aerogel functionalized separators to realize ultra-stable Zn metal batteries. 展开更多
关键词 zn metal batteries Aerogel interface Plasma zn^(2+)migration kinetics Dendrite growth
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