检索结果-南通市图书馆

nitrogen dioxide-Induced Responses in Brassica campestris Seedlings: The Role of Hydrogen Peroxide in the Modulation of Antioxidative Level and Induced Resistance

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2007年第10期6卷 1193-1200页

作者： MA Chun-yan XU Xin HAO Lin CAO Jun Department of Biology Shenyang Normal University Shenyang 110034 P.R.China Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 P.R.China

This article investigates the responses of Brassica campestris seedlings to an acute level of nitrogen dioxide （NO2） exposure in a plant growth chamber, and examines whether pretreating plants with hydrogen peroxide （H2O2） will alleviate NO2-caused injury. Twenty-eight-day-old B. campestris plants sprayed with 10 mmol L^-1 H2O2 aqueous solution （corresponding to approximate 1.0 mg H2O2 per single plant） were exposed to different concentrations of NO2 （0.25, 0.5, 1.0, and 2.0 μL L^-1, respectively） for 24 h under controlled environment. To measure the plant biomass, the plants were fumigated with the same NO2 concentrations as mentioned above for 7 h per day （8.00-15.00） for 7 days. As a control, charcoal filtered air alone was applied. Data were collected on plant biomass, total chlorophyll, photosynthetic rate, stomatal conductance, nitrate and nitrate reductase （NR）, antioxidative enzymes, ascorbate （ASA）, and malondialdehyde （MDA）, immediately after exposure. The results showed that exposure to a moderate dose of NO2 （e.g., 0.25 μL L^-1） had a favorable effect on plants, and the dry weight of the above-ground part increased, whereas the exposure to high NO2 concentrations （e.g., 0.5 μL L^-1 or higher） caused a reduction in the plant biomass and the total chlorophyll, when compared with the control. In addition, at 0.5 μL L^-1 or higher NO2 concentrations, prominent increases in the MDA level and superoxide dismutase （SOD） and NR activities were observed. Exposure to 1 μL L^-1 and higher NO2 resulted in necroses appearing on older leaves, and an increase in catalase （CAT） activity, decrease in ASA content, increased accumulation of NO3^-, and reduction in photosynthesis, when compared with the controls. No changes were detected in stomatal conductance under NO2 fumigation. The pretreatment with 10 mmol L^-1 H2O2 alleviated significantly NO2- caused biomass decrease and photosynthetic inhibition when compared with H2O2-untreated plants. Under NO2 fumigation, furthe

关键词： nitrogen dioxide hydrogen peroxide antioxidative system Brassica campestris L. ssp. chinensis (L.) Makino var. cammunis Tsen et Lee

Heterogeneous uptake of nitrogen dioxide on Chinese mineral dust

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2015年第12期27卷 110-118页

作者： Li Zhou Weigang Wang Siqi Hou Shengrui Tong Maofa Ge Beijing National Laboratory for Molecular Science (BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesInstitute of ChemistryChinese Academy of Sciences Beijing National Laboratory for Molecular Science (BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable SpeciesPeking University

Mineral dust is one of the major aerosols in the *** assess its impact on trace atmospheric gases,in this work we present a laboratory study of the effect of temperature on the heterogeneous reaction of NO2 on the surface of ambient Chinese dust over the temperature range from 258 to 313 *** results suggest that nitrogen dioxide could mainly be adsorbed on these types of Chinese mineral dust reversibly with little temperature *** to a previous study on NO2 uptake on mineral aerosols,the uptake coefficients are mainly on the order of 10^（-6） for the Chinese dust,when BET areas are taken into *** was observed as a product,and its formation and decomposition on Chinese mineral dust during the uptake processes were also *** complete dataset from this study was compiled with previous literature *** implications of the heterogeneous reaction between NO2 and mineral dust are also discussed,in an effort to understand this important heterogeneous process.

关键词： Mineral dust nitrogen dioxide Uptake coefficient Temperature dependence

Porous reduced graphene oxide for ultrasensitive detection of nitrogen dioxide

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2023年第1期34卷 511-516页

作者： Zengyong Chu Min Xiao Qichao Dong Guochen Li Tianjiao Hu Ye Zhang Zhenhua Jiang College of Liberal Arts and Science National University of Defense TechnologyChangsha 410073China

The defect engineering in graphene plays a significant role for the application of gas sensors. In this work, we proposed an efficient method to prepare ultrasensitive gas sensors based on the porous reduced graphene oxide(PRGO). Photo-Fenton etching was carried out on GO nanosheets in a controlled manner to enrich their vacancy defects. The resulting porous graphene oxide(PGO) was then drop-coated on interdigital electrodes and hydrothermal reduced at 180 °C. Controllable reduction was achieved by varying the water amount. The gas sensor based on PRGO-5 min-6h exhibited superior sensing and selective performance toward nitrogen dioxide(NO2), with an exceptional high sensitivity up to 12 *** theoretical limit of detection is down to 0.66 ppb. The excellent performance could be mainly attributed to the typical vacancy defects of PRGO. Some residue carboxylic groups on the edges could also facilitate the adsorption of polar molecules. The process has a great potential for scalable fabrication of high-performance NO2gas sensors.

关键词： Gas sensors nitrogen dioxide Graphene oxide Photo-fenton reaction Porous reduced graphene oxide

Comparative Analysis of Indoor Levels of Suspended Particulates and nitrogen dioxide a Few Hours later after an Asthmatic Attack

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2007年第11期25卷 1669-1674页

作者： UKPEBOR, Emmanuel Ehiabhi OKUO, James Majebi EKANEM, Victor James UKPEBOR, Justina Ebehirieme Air Pollution Research Group Department of Chemistry University of Benin Benin City Nigeria Department of Pathology University of Benin/University of Benin Teaching Hospital PMB 1154 Benin City Nigeria

Suspended particulates （TSP） and nitrogen dioxide （NO2） are known respiratory irritants linked to asthma aggravation. This pilot study was designed to investigate the role of these pollutants on the frequency of asthmatic attack on two of the inhabitants of a household. The surveillance of TSP and NO2 in this household commenced a few hours later, after one of the occupants suffered an attack. The TSP load determination was done using a High Volume Gravimetric sampler and a light scattering method via a Haz-Dust 10 μm particulate monitor. Palmes Diffusion tubes for NO2 and a portable Crowcon Gasman toxic gas detector were utilized for NO2 screening. In the first day of monitoring in the living room, the in situ particulate sampler （Haz-Dust） recorded a mean TSP level of 26,000 μg·m^-3. A confirmatory test with the eight hour average Gravimetric sampler gave 25,833 μg·m^-3. With the use of the Gasman toxic gas detector for NO2, the NO2 concentration for the first few hours of sampling was lower than 188 μg·m^-3, the detection limit of this instrument. However, the exact NO2 concentrations for the 7 day monitoring after the attack were 27.50 μg·m^-3 （kitchen） and 12.03 μg·m^-3 （living room） as recorded by the Palmes diffusion tubes.

关键词： nitrogen dioxide total suspended particulate asthma

Ambient nitrogen dioxide and Hospitalizations of Full-Spectrum Respiratory Diseases:A National Case-Crossover Study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Environment & Health 2023年第2期1卷 130-138页

作者： Cong Liu Renjie Chen Jian Lei Yixiang Zhu Lu Zhou Xia Meng Jianwei Xuan Haidong Kan School of Public Health Key Lab of Public Health Safety of the Ministry of EducationNHC Key Lab of Health Technology AssessmentIRDR ICoE on Risk Interconnectivity and Governance on Weather/Climate Extremes Impact and Public HealthFudan UniversityShanghai 200032China

Few multicity studies have examined the acute effects of nitrogen dioxide(NO_(2))on respiratory disease(RD),especially its specific *** study aimed to investigate the associations between short-term exposure to NO_(2)and hospitalization of full-spectrum RDs in *** of 10 major categories and 40 cause-specific RDs were obtained from 20 provinces over the study period of 2013−2020.A time-stratified case-crossover study was conducted at the individual level to explore the associations between NO_(2)and ***_(2)was significantly associated with increased hospitalization of eight major RDs(acute upper respiratory infections,influenza and pneumonia,acute lower respiratory infections,upper respiratory tract diseases,chronic lower respiratory diseases,respiratory interstitium diseases,pleura diseases,and other respiratory diseases)and 18 specific causes of RDs,with the largest associations observed on lag 0−1 *** effect estimates ranged from 0.75 to 4.09%per 10μg/m^(3)of NO_(2)*** associations remained robust after controlling for *** concentration−response curves were mostly positive and *** nationwide study provides comprehensive information on the acute effects of NO_(2)on respiratory morbidity across the full spectrum,highlighting the need for caution with regard to this important traffic-related air pollutant in current pollution control programs.

关键词： nitrogen dioxide respiratory disease hospitalization cause-specific case-crossover study

nitrogen dioxide Fumigation for Microbial Control on Unshelled Peanuts*

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Agricultural Sciences 2020年第12期11卷 1159-1169页

作者： Sookyung Oh Rippy Singh Yong-Biao Liu^# U.S. Department of Agriculture Agricultural Research Service Crop Improvement and Protection Unit Salinas USA

Stored peanuts often need treatments to control microbial infections as well as insects to maintain postharvest quality. Nitric oxide (NO) is a recently discovered fumigant for postharvest pest control. NO fumigation must be conducted under ultralow oxygen condition to preserve NO and always contains NO2 due to NO reaction with oxygen and NO2 has antimicrobial property. Therefore, NO fumigation has potential to control both pests and pathogens. In this study, we evaluated antimicrobial effects of NO2 fumigation on unpasteurized unshelled peanuts. Peanuts were fumigated with 0.3%, 1.0%, and 3.0% NO2 for three days at 25˚C by injecting NO gas into glass jars to react with O2 in the atmosphere. After fumigation, wash-off microbial samples were collected from intact peanut samples and, then, cracked open peanut samples with non-selective tryptic soy broth medium. The wash-off samples were then diluted with both the non-selective medium and a fungal-selective potato dextrose broth medium and were tested on GreenLight™ rapid enumeration test based on oxygen depletion on culture medium. All three NO2 fumigation treatments showed significant antibacterial and antifungal effects on intact peanuts as well as on cracked peanuts with complete inhibition with 3.0% NO2. Fumigation did not have obvious effects on appearance of skinned peanut kernels. These results suggested that NO2 fumigation has potential to control microbes on stored products, and NO fumigation with the combination of NO and NO2 has potential to control both insects and microbes on stored products.

关键词： nitrogen dioxide Nitric Oxide Postharvest Fumigation Microbes Peanuts

Optical-optical double-resonant multiphoton ionization spectra of Rydberg states of nitrogen dioxide

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2005年第3期14卷 524-528页

作者：张贵银张连水孙博韩小峰于威 CollegeofPhysicsScienceandTechnology HebeiUniversityBaoding071002China

The optical-optical double-resonant multiphoton ionization(OODR-MPI) technique has been applied to the study of the Rydberg states of nitrogen dioxide. The results show that ,althougy the OODR-MPI spectra of NO2 are composed of regular progression bands at different pump laser intensities, their ionization pathways are *** NO2 mollecule is ionized through the (3+1+1)double-resonant process as the pump laser intensity is in a high value, or else it is through the (1+2+1)*** final resonant states in the two ionizing processes have been attributed to different Rydberg states.

关键词： OODR-MPI nitrogen dioxide Rydberg states

Analysis of nitrogen dioxide in Environment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Bioscience and Biotechnology 2016年第6期7卷 278-288页

作者： Jun Wang Wei Zhang Rui Cao Xiangyu You Hong Lai Department of Pharmacy Food and Pharmaceutical Engineering College Hubei University of Technology Wuhan Hubei China C. Eugene Bennett Department of Chemistry West Virginia University Morgantown WV USA Department of Chemistry Johns Hopkins University Baltimore Maryland USA Department of Radiology Johns Hopkins School of Medicine Baltimore Maryland USA

As a severe environmental pollutant, detection and quantitation of nitrogen dioxide (NO2) have been studied for centuries. In this review, recent progress of NO2 analysis in the atmosphere will be summarized. Four major types of detection technologies, including traditional chemical detection, optical detection, solid-state field effect transistor detection, and other detection technology are covered. The standard method employed by the US EPA, which is based on luminol, is the most reliable and robust method that is used for fully validated monitoring. In the past two decades, accompanying the fast development of electrical engineering and integrated circuit, micro to nanoscale gas sensors have been gaining more and more attention. Application of novel materials including nano wires and graphene also leads to a new era of research and development of sensors.

关键词： nitrogen dioxide Chemical Detection Optical Detection Field-Effect Transistor Detection Luminol

Vertical Distributions of Ozone and nitrogen dioxide Observed in a Polluted Marine Boundary Layer around Kaohsiung City

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Vertical Distributions of Ozone and Nitrogen Dioxide Observe...