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Hybrid modeling for carbon monoxide gas-phase catalytic coupling to synthesize dimethyl oxalate process
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作者 Shida Gao Cuimei Bo +3 位作者 Chao Jiang Quanling Zhang Genke Yang Jian Chu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第6期234-250,共17页
Ethylene glycol(EG)plays a pivotal role as a primary raw material in the polyester industry,and the syngas-to-EG route has become a significant technical route in production.The carbon monoxide(CO)gas-phase catalytic ... Ethylene glycol(EG)plays a pivotal role as a primary raw material in the polyester industry,and the syngas-to-EG route has become a significant technical route in production.The carbon monoxide(CO)gas-phase catalytic coupling to synthesize dimethyl oxalate(DMO)is a crucial process in the syngas-to-EG route,whereby the composition of the reactor outlet exerts influence on the ultimate quality of the EG product and the energy consumption during the subsequent separation process.However,measuring product quality in real time or establishing accurate dynamic mechanism models is challenging.To effectively model the DMO synthesis process,this study proposes a hybrid modeling strategy that integrates process mechanisms and data-driven approaches.The CO gas-phase catalytic coupling mechanism model is developed based on intrinsic kinetics and material balance,while a long short-term memory(LSTM)neural network is employed to predict the macroscopic reaction rate by leveraging temporal relationships derived from archived measurements.The proposed model is trained semi-supervised to accommodate limited-label data scenarios,leveraging historical data.By integrating these predictions with the mechanism model,the hybrid modeling approach provides reliable and interpretable forecasts of mass fractions.Empirical investigations unequivocally validate the superiority of the proposed hybrid modeling approach over conventional data-driven models(DDMs)and other hybrid modeling techniques. 展开更多
关键词 Carbon monoxide Dynamic modeling Hybrid model Reaction kinetics Semi-supervised learning
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Absolute partial and total ionization cross sections of carbon monoxide with electron collision from 350 eV to 8000 eV
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作者 Taj Wali Khan 黄伟哲 +2 位作者 王恩亮 单旭 陈向军 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期459-464,共6页
The absolute partial and total cross sections for electron impact ionization of carbon monoxide are reported for electron energies from 350 eV to 8000 eV.The product ions(CO^(+),C^(+),O^(+),CO^(2+),C^(2+),and O^(2+))a... The absolute partial and total cross sections for electron impact ionization of carbon monoxide are reported for electron energies from 350 eV to 8000 eV.The product ions(CO^(+),C^(+),O^(+),CO^(2+),C^(2+),and O^(2+))are measured by employing an ion imaging mass spectrometer and two ion-pair dissociation channels(C^(+)+O^(+)and C^(2+)+O^(+))are identified.The absolute cross sections for producing individual ions and their total,as well as for the ion-pair dissociation channels are obtained by normalizing the data of CO^(+)to that of Ar^(+)from CO-Ar mixture target with a fixed 1:1 ratio.The overall errors are evaluated by considering various kinds of uncertainties.A comprehensive comparison is made with the available data,which shows a good agreement with each other over the energy ranges that are overlapped.This work presents new cross-section data with electron energies above 1000 eV. 展开更多
关键词 electron impact ionization cross sections carbon monoxide ion imaging mass spectrometer
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COPD病人一氧化碳弥散量与运动耐力、呼吸困难及通气效率的相关性研究
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作者 王瑞萍 张妮 《实用老年医学》 CAS 2024年第2期141-144,148,共5页
目的 探讨COPD病人一氧化碳弥散量(DLCO)与运动耐力、呼吸困难、通气效率的相关性。方法 入选60例稳定期COPD病人,根据单位肺泡容积的弥散量(DLCO/V_(A))将病人分为正常DLCO组和低DLCO组,收集2组静态肺功能、心肺运动试验(CPET)参数,并... 目的 探讨COPD病人一氧化碳弥散量(DLCO)与运动耐力、呼吸困难、通气效率的相关性。方法 入选60例稳定期COPD病人,根据单位肺泡容积的弥散量(DLCO/V_(A))将病人分为正常DLCO组和低DLCO组,收集2组静态肺功能、心肺运动试验(CPET)参数,并采用呼吸困难量表(mMRC)对呼吸困难进行评分。采用相关分析以及多重线性回归分析DLCO与运动耐力、呼吸困难、通气效率的相关性。结果 低DLCO组的一氧化碳弥散量占预计值百分比[(DLCO/V_(A))/pred]、最大功率负荷(Peak Load)、峰值摄氧量占预计值的百分比(Peak VO_(2)/pred)、每公斤体质量峰值摄氧量(Peak VO_(2)/kg)均低于正常DLCO组,无氧阈时CO_(2)通气当量(EQCO_(2)@AT)、mMRC评分均高于正常DLCO组,差异有统计学意义(P<0.01)。相关性分析显示,(DLCO/V_(A))/pred与Peak Load、Peak VO_(2)/pred、Peak VO_(2)/kg呈正相关,与EQCO2@AT、mMRC评分呈负相关(P<0.05)。多重线性回归分析结果显示,(DLCO/V_(A))/pred是预测COPD病人呼吸困难、运动耐力以及通气效率的独立预测因子(P<0.05)。结论 DLCO与COPD病人的呼吸困难、运动耐力、通气效率独立相关。 展开更多
关键词 慢性阻塞性肺疾病 一氧化碳弥散量 运动耐力 通气效率 呼吸困难
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Optical spectroscopy of CrO and electronic states of the Cr group metal monoxides
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作者 张磊 于尧 +1 位作者 马新文 杨杰 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期63-75,共13页
All of the experimentally known electronic states of the Cr group metal monoxides(Cr O,Mo O,and WO)have been presented in the paper.The optical spectra of the Cr O molecule have been investigated in the gas phase thro... All of the experimentally known electronic states of the Cr group metal monoxides(Cr O,Mo O,and WO)have been presented in the paper.The optical spectra of the Cr O molecule have been investigated in the gas phase through a combination of the laser-induced fluorescence(LIF)excitation and single-vibronic-level(SVL)emission spectroscopy in the supersonic expansion.The rotational constants of the vibronic electronic states,including X^(5)Π_(-1)(v=0–3),B^(5)Π_(-1)(v=0–10),and B~5Π_1(v=1,5),and the vibrational constants of the spin–orbit components X^(5)Π_(-1,0,1)have been obtained.The molecular constants of the Mo O and WO molecules have been summarized by reviewing the previous spectroscopic studies,and a comprehensive energy level diagram of the Cr group metal monoxides has been constructed.By comparing the electronic configurations,bond lengths,and vibrational frequencies of all the transition metal monoxides in the ground electronic state,the significance of the relativistic effect in the bonding of the 5d transition metal monoxides has been discussed.The related spectroscopic data of the Cr O molecule are available at https://doi.org/10.57760/sciencedb.j00113.00085. 展开更多
关键词 laser-induced fluorescence(LIF) transition metal monoxide electronic state molecular constant relativistic effect
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Association of carbon monoxide poisonings and carboxyhemoglobin levels with COVID-19 and clinical severity
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作者 Abuzer Coskun Burak Demirci Kenan Ahmet Turkdogan 《World Journal of Methodology》 2023年第4期248-258,共11页
BACKGROUND Coronavirus disease 2019(COVID-19),which recently spread throughout the entire world,is still a significant health issue.Additionally,the most common cause of risky poisoning in emergency services is carbon... BACKGROUND Coronavirus disease 2019(COVID-19),which recently spread throughout the entire world,is still a significant health issue.Additionally,the most common cause of risky poisoning in emergency services is carbon monoxide(CO)poisoning.Both disorders seem to merit more research as they have an impact on all bodily systems via the lungs.AIM To determine how arterial blood gas and carboxyhemoglobin(COHb)levels affect the clinical and prognostic results of individuals requiring emergency treatment who have both COVID-19 and CO poisoning.METHODS Between January 2018 and December 2021,479 CO-poisoning patients participated in this single-center,retrospective study.Patients were primarily divided into two groups for analysis:Pre-pandemic and pandemic periods.Additionally,the pandemic era was divided into categories based on the presence of COVID-19 and,if present,the clinical severity of the infection.The hospital information system was used to extract patient demographic,clinical,arterial blood gas,COVID-19 polymerase chain reaction,and other laboratory data.RESULTS The mean age of the 479 patients was 54.93±11.51 years,and 187(39%)were female.226(47%)patients were in the pandemic group and 143(30%)of them had a history of COVID-19.While the mean potential of hydrogen(pH)in arterial blood gas of all patients was 7.28±0.15,it was 7.35±0.10 in the pre-pandemic group and 7.05±0.16 in the severe group during the pandemic period(P<0.001).COHb was 23.98±4.19%in the outpatients and 45.26%±3.19%in the mortality group(P<0.001).Partial arterial oxygen pressure(PaO2)was 89.63±7.62 mmHg in the pre-pandemic group,and 79.50±7.18 mmHg in the severe group during the pandemic period(P<0.001).Despite the fact that mortality occurred in 35(7%)of all cases,pandemic cases accounted for 30 of these deaths(85.7%)(P<0.001).The association between COHb,troponin,lactate,partial arterial pressure of carbon dioxide,HCO3,calcium,glucose,age,pH,PaO2,potassium,sodium,and base excess levels in the pre-pandemic and pandemic groups was statistically significant in univariate linear analysis.CONCLUSION Air exchange barrier disruption caused by COVID-19 may have pulmonary consequences.In patients with a history of pandemic COVID-19,clinical results and survival are considerably unfavorable in cases of CO poisoning. 展开更多
关键词 Emergency department coronavirus disease 2019 Carbon monoxide MORTALITY CARBOXYHEMOGLOBIN INTOXICATION POISONING
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Intracardiac Thrombosis Secondary to the Silent Killer: A Case Report about Monoxide Carbon Poisoning in a Child
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作者 Madiha Benhachem Mariem Labrahimi +3 位作者 Aziza Elouali Ayyad Ghannam Maria Rkain Abdeladim Babakhouya 《Open Journal of Pediatrics》 2023年第4期502-506,共5页
Carbon monoxide (CO) poisoning is a frequent cause of emergency room admissions, especially during winter days, the symptoms are varied ranging from a simple headache to a serious cardiac and neurological impairment t... Carbon monoxide (CO) poisoning is a frequent cause of emergency room admissions, especially during winter days, the symptoms are varied ranging from a simple headache to a serious cardiac and neurological impairment that can be deadly. Diagnosis is based on the circumstances of occurrence as well as the dosage of carboxyhemoglobin in the blood. Exposure to CO has serious consequences, neurological and cardiac manifestations are not negligible and vary from repolarization disorders to heart attack. Treatment is urgent with normobaric or hyperbaric oxygen therapy. We report a case of a 2-year male child admitted to the emergency room for CO intoxication with an intracardiac thrombus subsequently complicated by an ischemic stroke with a fatal outcome in order to highlight this complication rarely described in literature. 展开更多
关键词 Carbon monoxide (co) POISONING Intracardiac Thrombosis CHILD
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Effects of Chlorine and Chlorine Monoxide on Stratospheric Ozone Depletion 被引量:1
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作者 Laurie Wei Ibraheem Alelmi Sen Nieh 《Atmospheric and Climate Sciences》 2024年第1期136-153,共18页
This paper presents a system approach of mass balance calculations of ozone and other species under diffusion-convection-reaction processes to study the impacts of major ozone-depleting chemicals, chlorine (Cl) and ch... This paper presents a system approach of mass balance calculations of ozone and other species under diffusion-convection-reaction processes to study the impacts of major ozone-depleting chemicals, chlorine (Cl) and chlorine monoxide (ClO), and the effect of photolysis on ozone concentrations, ozone depletion, total ozone abundance, and ozone layer along the altitude in the stratosphere. The calculated ozone concentrations and profile of the layer followed a similar trend and were generally in good agreement with the measurements above the tropical area. The calculated peak of the layer was at the same mid-stratosphere at Z = 30 km with a peak concentration and total ozone abundance about 20% higher than the measured peak concentration of 8.0 ppm and total abundance of 399 DU. In the presence of Cl and ClO, the calculated ozone concentrations and total abundance were substantially reduced. Cl generally depleted more uniformly of ozone across the altitude, while ClO reduced substantially the ozone in the upper stratosphere and thus shifted the peak of the layer to a much lower elevation at Z = 14 km. Although both ClO and Cl are active ozone-depleting chemicals, ClO was found to have a more pronounced impact on ozone depletion and distribution than Cl. The possible explanations of these interesting phenomena were discussed and elaborated. The approach and calculations in this paper were shown to be useful in providing an initial insight into the structure and behavior of the complex ozone layer. 展开更多
关键词 OZONE Ozone Depletion CHLORINE Chlorine monoxide PHOTOLYSIS Dobson Unit
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Rational design of F,N-rich artificial interphase via chemical prelithiation initiation strategy enabling high coulombic efficiency and stable micro-sized SiO anodes
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作者 Quanyan Man Hengtao Shen +3 位作者 Chuanliang Wei Baojuan Xi Shenglin Xiong Jinkui Feng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期224-232,共9页
Silicon monoxide(SiO)is regarded as a potential candidate for anode materials of lithium-ion batteries(LIBs).Unfortunately,the application of SiO is limited by poor initial Coulombic efficiency(ICE)and unsteady solid ... Silicon monoxide(SiO)is regarded as a potential candidate for anode materials of lithium-ion batteries(LIBs).Unfortunately,the application of SiO is limited by poor initial Coulombic efficiency(ICE)and unsteady solid electrolyte interface(SEI),which induce low energy,short cycling life,and poor rate properties.To address these drawbacks of SiO,we achieve in-situ construction of robust and fast-ion conducting F,N-rich SEI layer on prelithiated micro-sized SiO(P-μSiO)via the simple and continuous treatment ofμSiO in mild lithium 4,4′-dimethylbiphenyl solution and nonflammable hexafluorocyclotriphosphazene solution.Chemical prelithiation eliminates irreversible capacity through pre-forming inactive lithium silicates.Meanwhile,the symbiotic F,N-rich SEI with good mechanical stability and fast Li^(+)permeability is conductive to relieve volume expansion ofμSiO and boost the Li+diffusion kinetics.Consequently,the P-μSiO realizes an impressive electrochemical performance with an elevated ICE of 99.57%and a capacity retention of 90.67%after 350 cycles.Additionally,the full cell with P-μSiO anode and commercial LiFePO_(4) cathode displays an ICE of 92.03%and a high reversible capacity of 144.97 mA h g^(-1).This work offers a general construction strategy of robust and ionically conductive SEI for advanced LIBs. 展开更多
关键词 Chemical prelithiation Silicon monoxide SEI Lithium-ion batteries INTERPHASE engineering
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Single atom Cu-N-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode
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作者 S.Pérez-Rodríguez M.Gutiérrez-Roa +6 位作者 C.Giménez-Rubio D.Ríos-Ruiz P.Arévalo-Cid M.V.Martínez-Huerta A.Zitolo M.J.Lázaro D.Sebastián 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期169-182,I0004,共15页
The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped c... The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V vs.RHE) in 0.1 M KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/CO ratio of 1.8. These results demonstrate that RRDE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR. 展开更多
关键词 Cu-N-C Carbon xerogel Rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide
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Identifying influential spreaders in complex networks based on density entropy and community structure
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作者 苏湛 陈磊 +2 位作者 艾均 郑雨语 别娜 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期765-774,共10页
In recent years,exploring the relationship between community structure and node centrality in complex networks has gained significant attention from researchers,given its fundamental theoretical significance and pract... In recent years,exploring the relationship between community structure and node centrality in complex networks has gained significant attention from researchers,given its fundamental theoretical significance and practical implications.To address the impact of network communities on target nodes and effectively identify highly influential nodes with strong propagation capabilities,this paper proposes a novel influential spreaders identification algorithm based on density entropy and community structure(DECS).The proposed method initially integrates a community detection algorithm to obtain the community partition results of the networks.It then comprehensively considers the internal and external density entropies and degree centrality of the target node to evaluate its influence.Experimental validation is conducted on eight networks of varying sizes through susceptible–infected–recovered(SIR)propagation experiments and network static attack experiments.The experimental results demonstrate that the proposed method outperforms five other node centrality methods under the same comparative conditions,particularly in terms of information spreading capability,thereby enhancing the accurate identification of critical nodes in networks. 展开更多
关键词 coRRIGENDUM electron impact ionization cross sections carbon monoxide
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Carbon Monoxide Modulates Auxin Transport and Nitric Oxide Signaling in Plants under Iron Deficiency Stress
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作者 Kaiyue Hong Yasmina Radani +2 位作者 Waqas Ahmad Ping Li Yuming Luo 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第1期45-61,共17页
Carbon monoxide(CO)and nitric oxide(NO)are signal molecules that enhance plant adaptation to environmental stimuli.Auxin is an essential phytohormone for plant growth and development.CO and NO play crucial roles in mo... Carbon monoxide(CO)and nitric oxide(NO)are signal molecules that enhance plant adaptation to environmental stimuli.Auxin is an essential phytohormone for plant growth and development.CO and NO play crucial roles in modulating the plant’s response to iron deficiency.Iron deficiency leads to an increase in the activity of heme oxygenase(HO)and the subsequent generation of CO.Additionally,it alters the polar subcellular distribution of Pin-Formed 1(PIN1)proteins,resulting in enhanced auxin transport.This alteration,in turn,leads to an increase in NO accumulation.Furthermore,iron deficiency enhances the activity of ferric chelate reductase(FCR),as well as the expression of the Fer-like iron deficiency-induced transcription factor 1(FIT)and the ferric reduction oxidase 2(FRO2)genes in plant roots.Overexpression of the long hypocotyl 1(HY1)gene,which encodes heme oxygenase,or the CO donor treatment resulted in enhanced basipetal auxin transport,higher FCR activity,and the expression of FIT and FRO2 genes under Fe deficiency.Here,a potential mechanism is proposed:CO and NO interact with auxin to address iron deficiency stress.CO alters auxin transport,enhancing its accumulation in roots and up-regulating key iron-related genes like FRO2 and IRT1.Elevated auxin levels affect NO signaling,leading to greater sensitivity in root development.This interplay promotes FCR activity,which is crucial for iron absorption.Together,these molecules enhance iron uptake and root growth,revealing a novel aspect of plant physiology in adapting to environmental stress. 展开更多
关键词 Carbon monoxide nitric oxide AUXIN iron deficiency signal molecule PLANTS
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蛭石基FeCeO_(x)催化剂及CO选择性催化还原NO
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作者 高飞 刘志松 +4 位作者 潘珂珂 刘敏敏 代斌 但建明 于锋 《化工进展》 EI CAS CSCD 北大核心 2024年第4期1851-1862,共12页
以CO为还原剂去除NO的选择性催化还原(CO-SCR)技术受到了广泛关注。本文以天然矿物蛭石为载体,采用共沉淀辅助浸渍法(CP-IM)制备了蛭石负载的铁铈双金属氧化物(FeCe/VMT)用于CO-SCR脱硝反应。表征结果显示,相比传统的浸渍法(IM),共沉淀... 以CO为还原剂去除NO的选择性催化还原(CO-SCR)技术受到了广泛关注。本文以天然矿物蛭石为载体,采用共沉淀辅助浸渍法(CP-IM)制备了蛭石负载的铁铈双金属氧化物(FeCe/VMT)用于CO-SCR脱硝反应。表征结果显示,相比传统的浸渍法(IM),共沉淀辅助浸渍制备的FeCe/VMT催化剂具有更大的比表面积(106.9m^(2)/g)和更多氧空位,可以提供更多的活性位点。共沉淀过程形成更多Fe^(3+),并促进了FeCe间的协同作用,有利于提高CO-SCR的催化活性和稳定性。性能测试表明,在300℃和50000h^(−1)的空速下,NO转化率可达100%,48h后NO转化率几乎无衰减。当温度降至250℃时,NO的转化率依然可以达到97%。同时,利用原位红外光谱和密度泛函理论计算技术,揭示了相应的催化反应机理,为制备大比表面积的负载型催化剂提供了一种方法。 展开更多
关键词 催化剂 一氧化碳 选择催化还原 纳米材料 多相反应
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以CeO_(2)为载体的Fe基载氧体与CO反应机理模拟
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作者 穆林 孙萌 +4 位作者 张彬 尚妍 东明 陈建标 霍兆义 《洁净煤技术》 CAS CSCD 北大核心 2024年第2期114-122,共9页
化学链燃烧技术是一种新型的近“零碳”排放燃烧技术,载氧体在化学链燃烧反应过程中发挥着载氧和传热的双重作用。以活性催化组分为载体,通过调谐微观结构提高Fe基载氧体的反应性能是目前化学链领域的研究热点之一。基于密度泛函理论,以... 化学链燃烧技术是一种新型的近“零碳”排放燃烧技术,载氧体在化学链燃烧反应过程中发挥着载氧和传热的双重作用。以活性催化组分为载体,通过调谐微观结构提高Fe基载氧体的反应性能是目前化学链领域的研究热点之一。基于密度泛函理论,以CeO_(2)为活性催化载体,对Fe基载氧体进行催化调谐。通过优化构建组合物模型,系统分析了组合物模型中Fe_(2)O_(3)团簇不同点位吸附CO的态密度、吸附能、差分电荷密度和活化能等电子结构特性参数。研究结果表明,Fe_(2)O_(3)团簇的电子向CeO_(2)(111)表面转移,Fe_(2)O_(3)团簇的吸附能为-3.92 eV,Fe2O3团簇与CeO_(2)(111)表面稳定结合;态密度(DOS)分析发现负载后的Fe_(2)O_(3)团簇p和d轨道在-8~0 eV电子向费米能级方向迁移,表明吸附作用增强。Fe_(2)O_(3)团簇p和d轨道中电子减少,现存电子向高能级跃迁,Fe_(2)O_(3)团簇电子活性增强,CO分子在Fe_(2)O_(3)/CeO2复合载氧体的Fe_(2)O_(3)团簇3个吸附位反应的活化能均降低。此外,CeO_(2)(111)增强了CO在Fe_(2)O_(3)团簇Fe顶位的吸附作用,吸附能由-0.33 eV增至-1.78 eV;同时,削弱了在O顶位的过强吸附作用,吸附能由-2.69 eV降至-2.32 eV,有利于后期CO_(2)分子脱离Fe_(2)O_(3)团簇表面,从而有效调谐Fe2O3团簇整体对CO的吸附效果,为Fe基载氧体的设计制备和优化调谐提供理论指导。 展开更多
关键词 Fe基载氧体 CeO_(2)载体 密度泛函理论 一氧化碳 催化
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CRDS和GC方法在线监测大气CH_(4)和CO的结果对比
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作者 吴栋桥 王凯 +3 位作者 孙万启 秦正新 潘京京 王红阳 《中国环境监测》 CAS CSCD 北大核心 2024年第5期179-186,共8页
光腔衰荡光谱法(CRDS)和色谱法(GC)均可用于甲烷(CH_(4))和一氧化碳(CO)的在线观测。金沙大气本底站建立了基于CRDS和GC的平行观测系统,对大气中的CH_(4)和CO进行了长达一年半的在线观测试验,对二者获取的数据进行了对比分析。结果表明:... 光腔衰荡光谱法(CRDS)和色谱法(GC)均可用于甲烷(CH_(4))和一氧化碳(CO)的在线观测。金沙大气本底站建立了基于CRDS和GC的平行观测系统,对大气中的CH_(4)和CO进行了长达一年半的在线观测试验,对二者获取的数据进行了对比分析。结果表明:CRDS对CH_(4)和CO观测的长期稳定性和准确性明显优于GC;CRDS和GC获取CH_(4)的系统偏差满足世界气象组织全球大气观测计划(WMO/GAW)的兼容性指标要求,获取CO的系统偏差不满足兼容性指标要求;CRDS和GC获取CH_(4)的日变化曲线基本重合,均呈现双峰形态,获取CO的日变化曲线也基本重合,但变化特征均不明显;CRDS和GC获取CH_(4)的季节变化曲线基本重合,7—8月最低,与北半球变化趋势吻合,获取的CO季节变化曲线趋势上基本一致,在夏季7月出现谷值。 展开更多
关键词 光腔衰荡光谱法 气相色谱法 甲烷 一氧化碳 在线监测
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外源CO和H_(2)S对NaCl胁迫下加工番茄幼苗光合及叶绿素荧光动力学的影响
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作者 骆霞 滕元旭 崔辉梅 《植物营养与肥料学报》 CAS CSCD 北大核心 2024年第3期538-549,共12页
[目的]研究一氧化碳(CO)和硫化氢(H_(2)S)调控作物幼苗抗盐能力的机理,为缓解盐渍土中NaCl对作物的胁迫提供理论和技术。[方法]以加工番茄品系KT-7为试验材料,采用无土栽培方法进行CO和H_(2)S叶面喷施试验。CO供体为氯化血红素溶液(hemi... [目的]研究一氧化碳(CO)和硫化氢(H_(2)S)调控作物幼苗抗盐能力的机理,为缓解盐渍土中NaCl对作物的胁迫提供理论和技术。[方法]以加工番茄品系KT-7为试验材料,采用无土栽培方法进行CO和H_(2)S叶面喷施试验。CO供体为氯化血红素溶液(hemin 15μmol/L),H_(2)S供体为硫氢化钠溶液(NaHS,50μmol/L),并因处理需要使用了H_(2)S清除剂次牛磺酸溶液(HT,100μmol/L)和血红素加氧酶抑制剂锌原卟啉溶液(ZnPPⅨ,25μmol/L)。试验共设6个处理,除对照根部浇灌营养液,叶面喷施清水外(CK_(0)),其余5个处理均根部浇灌200 mmol/L NaCl溶液,叶面分别喷施清水(CK_(1))、CO、H_(2)S、CO+HT、H_(2)S+ZnPPⅨ。幼苗长至四叶一心时,连续6天进行NaCl浇灌和叶面喷施处理,然后测定幼苗形态学指标,用Li-6800便携式光合测定仪测定光合参数,用Imaging-PAM荧光成像系统测定叶绿素荧光系数,植物效率仪测定叶绿素荧光动力学曲线(OJIP曲线)。[结果]胁迫6天后,加工番茄幼苗的各项形态学参数、净光合速率(P_(n))、实际光化学效率[Y(Ⅱ)]和光系统Ⅱ(PSⅡ)性能指标[PI_(ABS)和PI_((CSM))]显著下降,OJIP曲线产生形变,并出现K点。CO和H_(2)S处理均有效提高了加工番茄幼苗的光合色素含量、光合参数、PSⅡ的综合性能和受体侧的电子传递效率;提升了OJIP曲线中的J点、I点、P点,降低了ΔK,从而缓解了OJIP曲线的形变;CO处理的P_(n)、表观CO^(2)利用率(CUEapp)、Y(Ⅱ)和电子传递速率(ETR)分别较CK_(1)上升了75.63%、100%、60.00%和57.72%,H_(2)S处理分别上升了65.95%、100%、55.00%和52.68%,CO和H_(2)S处理均降低了非光化学淬灭和热耗散的比例,减少了PSⅡ供体侧放氧复合体(OEC)的损伤。CO+HT处理缓解NaCl胁迫的效果和CO处理相似,而H_(2)S+ZnPPⅨ处理则不能缓解NaCl胁迫,其光合色素含量、P_(n)、F_(v)/F_(m)、Y(Ⅱ)、qL、ETR、PI_(ABS)和PI_((CSM))较H_(2)S处理显著下降,热耗散比率则较H_(2)S处理显著升高。[结论]外源施用CO和H_(2)S均可通过提高光合效率,优化PSⅡ能量分配比率,保护光合电子传递链免受盐害损伤,显著提高番茄幼苗的抗盐能力。CO的作用位点可能在H_(2)S下游,具有协同H_(2)S提高加工番茄耐盐性的作用。 展开更多
关键词 一氧化碳 硫化氢 加工番茄 NACL胁迫 叶绿素荧光
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镍单原子催化剂的制备及其电催化CO_(2)还原研究
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作者 朱超 张浩杰 +3 位作者 田地 屈治国 邸宏宇 郑楠 《化学工业与工程》 CAS CSCD 北大核心 2024年第3期11-17,共7页
电催化CO_(2)还原反应(Electrocatalytic CO_(2)reduction reaction, CO_(2)RR)在解决全球变暖和能源危机方面有着巨大的应用潜力,但目前催化效率低、催化产物多样等问题限制了CO_(2)RR反应的商业化应用。采用一锅法、碳化法制备了一系... 电催化CO_(2)还原反应(Electrocatalytic CO_(2)reduction reaction, CO_(2)RR)在解决全球变暖和能源危机方面有着巨大的应用潜力,但目前催化效率低、催化产物多样等问题限制了CO_(2)RR反应的商业化应用。采用一锅法、碳化法制备了一系列不同镍含量的镍单原子催化剂,利用XRD、XPS、ICP-OES、HRTEM、HAADF-STEM、XAS等方法对镍单原子催化剂的形貌结构、原子价态、金属含量等方面进行表征,并通过电催化还原产物的法拉第效率(Faraday efficiency, FE)和电流密度(Current density,J)来评价其电催化性能。此外,还研究了电解实验装置的改变对升电催化性能的提升。实验结果表明,随着Ni单原子催化剂的Ni金属负载量增加,产物CO的FECO和JCO均增加。催化剂中Zn1Ni2-CN表现出了优异的CO_(2)RR催化性能,在H型电解池中,在-0.7 V vs. RHE电位下FECO达到89%,在-0.9 V vs. RHE下JCO达到6.99 mA·cm^(-2)。在流动电解池中,大范围电位变化下(-0.4~-1.2 V vs. RHE)FECO均保持在99%以上,且在-1.2 V vs. RHE电位下产物电流密度JCO达到174.5 mA·cm^(-2)。 展开更多
关键词 镍单原子 电催化 co_(2)RR co
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气相色谱法测定异戊烷中微量CO、CO_(2)的研究 被引量:1
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作者 方协灵 胡锐 《石油炼制与化工》 CAS CSCD 北大核心 2024年第4期91-94,共4页
利用高压液体进样阀-气相色谱仪,结合镍转化炉,建立了一种测定异戊烷中微量CO和CO_(2)含量的分析方法,考察了方法的精密度、回收率以及最低检测限,并对实际异戊烷样品中CO、CO_(2)的含量进行分析。定量分析结果表明,标样组分的回收率为9... 利用高压液体进样阀-气相色谱仪,结合镍转化炉,建立了一种测定异戊烷中微量CO和CO_(2)含量的分析方法,考察了方法的精密度、回收率以及最低检测限,并对实际异戊烷样品中CO、CO_(2)的含量进行分析。定量分析结果表明,标样组分的回收率为98.0%,重复3次测定的相对标准偏差小于3%。CO、CO_(2)的最低检测限分别为0.13μL L和0.26μL L,该方法完全可以满足全密度聚乙烯工艺对异戊烷中微量CO、CO_(2)的质量监控要求。 展开更多
关键词 异戊烷 一氧化碳 二氧化碳 镍转化炉 高压液体进样阀
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基于TDLAS测量的痕量CO常温催化转化研究
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作者 樊景星 贺拴玲 +6 位作者 卢建彬 李天旺 韩世亮 李健韬 刘晓英 刘冠男 彭志敏 《激光与红外》 CAS CSCD 北大核心 2024年第6期908-914,共7页
CO作为火电、冶金、化工等行业产生的重要中间产物或排放物质,具有易燃、剧毒等特性,对其进行高精度在线检测对提高锅炉燃烧安全及实现碳减排具有重要意义。因此,本文采用可调谐二极管激光吸收光谱(TDLAS)和赫里奥特(Herriott)多次反射... CO作为火电、冶金、化工等行业产生的重要中间产物或排放物质,具有易燃、剧毒等特性,对其进行高精度在线检测对提高锅炉燃烧安全及实现碳减排具有重要意义。因此,本文采用可调谐二极管激光吸收光谱(TDLAS)和赫里奥特(Herriott)多次反射池实现了浓度为10^(-6)(μL/L)量级的CO高精度在线测量,其检测限可达到0.35μL/L。在此基础上,利用该测量系统开展了CO催化转化性能研究实验,探究催化剂含量及CO浓度对催化反应的影响。实验结果揭示了在常温常压、CO浓度为10~80μL/L下,CO催化转化效率随催化剂含量的变化规律,即催化剂含量越高,CO转化效率越高。实验结果可为采用稀释取样法测量CO浓度时提供去除稀释气中CO的方法,保证痕量CO浓度的准确测量。 展开更多
关键词 波长调制-直接吸收光谱(WM-DAS) 一氧化碳(co) 在线测量 催化反应
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Caco-2细胞单层缺氧再复氧损伤的模型构建
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作者 禹昭群 王晓红 《宁夏医学杂志》 CAS 2024年第3期194-197,F0002,I0001,共6页
目的构建Caco-2细胞单层缺糖、缺血清、缺氧,再复糖、复血清、复氧的损伤模型,探究一氧化碳释放分子3(CORM-3)对Caco-2细胞单层缺氧再复氧损伤模型的影响。方法首先,培养Caco-2细胞,于37℃、含5%CO_(2)、1%O_(2)与94%N_(2)的培养箱中缺... 目的构建Caco-2细胞单层缺糖、缺血清、缺氧,再复糖、复血清、复氧的损伤模型,探究一氧化碳释放分子3(CORM-3)对Caco-2细胞单层缺氧再复氧损伤模型的影响。方法首先,培养Caco-2细胞,于37℃、含5%CO_(2)、1%O_(2)与94%N_(2)的培养箱中缺氧,建立Caco-2细胞单层缺糖、缺血清、缺氧/复糖、复血清、复氧(H/R)模型。根据缺氧时间分4组,空白对照组(Control组)、H/R 1组(缺氧4 h、复氧4 h)、H/R 2组(缺氧8h、复氧4h)和H/R 3组(缺氧12 h、复氧4 h)。其次,溶解CORM-3药物粉末并制备无活性的CORM-3(iCORM-3),按药物浓度分6组,空白对照组(Control组)、缺氧、复氧损伤模型组(H/R组)、H/R+300μmol/L CORM-3(H/R+C1组)、H/R+400μmol/L CORM-3(H/R+C2组)、H/R+500μmol/L CORM-3(H/R+C3组)和H/R+500μmol/L iCORM-3(H/R+C4组)。主要采用Cell counting kit-8(CCK8)试剂盒检测细胞活力,倒置显微镜观察细胞形态变化,测定Caco-2细胞单层渗透性。结果随着缺氧时间的延长,可观察到Caco-2细胞间连接消失,细胞皱缩从培养瓶底脱落漂浮,细胞活力下降,细胞单层通透性增大。给予CORM-3药物干预处理后,相比于未干预损伤组Caco-2细胞均有不同程度的改善,细胞活力随着药物浓度的增加而上升。结论本研究成功构建Caco-2细胞单层缺氧再复氧的损伤模型,并发现CORM-3对Caco-2细胞单层H/R损伤模型可能有保护作用。 展开更多
关键词 CAco-2细胞单层 缺氧/复氧 外源性一氧化碳释放分子3
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大气压微波等离子体炬驱动Boudouard反应实现CO_(2)转化的研究
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作者 李寿哲 王兴昌 吴悦 《高电压技术》 EI CAS CSCD 北大核心 2024年第1期414-422,共9页
利用大气压CO_(2)微波等离子体放电的余辉和固态碳源相互作用进行布多阿尔反应,把CO_(2)转化为CO实现温室气体的资源化利用。通过发射光谱测量观察到微波等离子体炬驱动的布多阿尔反应中化学荧光复合过程的发生,测量了采用实心石墨棒时... 利用大气压CO_(2)微波等离子体放电的余辉和固态碳源相互作用进行布多阿尔反应,把CO_(2)转化为CO实现温室气体的资源化利用。通过发射光谱测量观察到微波等离子体炬驱动的布多阿尔反应中化学荧光复合过程的发生,测量了采用实心石墨棒时布多阿尔反应中CO_(2)转化效果随着功率的变化规律,进一步提出了以空心石墨棒作为布多阿尔反应的碳源,发现转化效果得到明显提高,并获得了随着功率、气体流量、石墨棒尺寸和组分变化的规律。另外,讨论了以不同种类的碳源作为反应物进行布多阿尔反应的实际对比效果及其相应的物理原因。实验结果表明CO_(2)等离子体余辉喷射到石墨棒表面发生的布多阿尔反应是实现CO_(2)到CO转化的重要过程;随着所使用的空心石墨棒内孔直径增加,生成的CO浓度也随之增大;在CO_(2)载气中以一定比例分别添加Ar或N2会增加CO的生成量。 展开更多
关键词 微波等离子体 布多阿尔反应 二氧化碳 一氧化碳 转化率
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