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Cell-Based Biological Markers for Blood-Enriching Chinese Herbs: Erythropoietin Production in HepG2 Cells and Nitric Oxide Release in Human Umbilical Vein Endothelial Cells (HUVECs)
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作者 Hoi Yan Leung Kam Ming Ko 《Chinese Medicine》 2023年第2期57-67,共11页
Chinese tonifying herbs, which are classified into four functional categories (namely, Yang, Qi, Yin, Blood) are commonly used for restoring normal body function and the prevention of diseases. To explore cell-based b... Chinese tonifying herbs, which are classified into four functional categories (namely, Yang, Qi, Yin, Blood) are commonly used for restoring normal body function and the prevention of diseases. To explore cell-based biological markers for Blood-enriching Chinese herbs, we investigate the effect of 11 commonly used Blood-enriching herbs on erythropoietin (EPO) production in HepG2 cells. Herbs for nourishing Yin were tested for determining the specificity of Blood-enriching herbs in inducing EPO production. In addition, the effects of Blood-enriching herbs on nitric oxide (NO) production in both HepG2 cells and human umbilical vein endothelial cells (HUVECs) were also investigated. The results indicated that methanolic extracts of Blood-enriching herbs (but not Yin-nourishing herbs) showed characteristic pharmacological activity in inducing EPO production in HepG2 cells and NO release in HUVECs. The experimental findings, therefore, support the use of cell-based EPO production and NO release as biological markers for Blood-enriching Chinese tonifying herbs. 展开更多
关键词 blood-Enriching Chinese Herbs ERYTHROPOIETIN Nitric oxide
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Effects of tropical forest conversion into oil palm plantations on nitrous oxide emissions:A meta-analysis 被引量:1
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作者 Taiki Mori 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第3期865-869,共5页
Oil palm plantations have dramatically expanded in tropical Asia over the past decades.Although their establishment has been projected to increase nitrous oxide(N_(2)O)emissions,earlier reports have shown inconsistent... Oil palm plantations have dramatically expanded in tropical Asia over the past decades.Although their establishment has been projected to increase nitrous oxide(N_(2)O)emissions,earlier reports have shown inconsistent results.This study analyzed these previously published data to compare N_(2)O emissions in oil palm plantations to reference forests.A linear mixed-eff ects model was used to examine the signifi cance of the eff ect of establishing oil palm plantations on N_(2)O emissions,rather than to calculate mean eff ect sizes because of limitations in the data structure.The results indicated that N_(2)O emissions were signifi cantly greater from oil palm plantations than from reference forests,as expected.This is the fi rst study to report the eff ect of oil palm plantations on N_(2)O emissions by synthesizing previously published data.To quantify the size of this eff ect,additional studies with frequent and long-term monitoring data are needed. 展开更多
关键词 META-ANALYSIS nitrogen fertilization Nitrous oxide Oil palm plantation Tropical forest
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Direct and Indirect Applications of Dielectric Barrier Discharge Plasma to Catalytic Reduction of Nitrogen Oxides from Exhaust Gas 被引量:7
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作者 YOUNG Sun Mok 《Plasma Science and Technology》 SCIE EI CAS CSCD 2006年第2期207-212,共6页
Dielectric barrier discharge (DBD) plasma was utilized to oxidize NO contained in the exhaust gas to NO2, ultimately improve the selective catalytic reduction of nitrogen oxides (NOx). In the one case, DBD was cre... Dielectric barrier discharge (DBD) plasma was utilized to oxidize NO contained in the exhaust gas to NO2, ultimately improve the selective catalytic reduction of nitrogen oxides (NOx). In the one case, DBD was created directly in the exhaust gas (direct application), and in the an other case, ozone produced by DBD was injected into the exhaust gas (indirect application). A comparative study between such direct and indirect applications of DBD plasma was made in terms of the NOx removal efficiency and the energy consumption. The NO2 content in the exhaust gas was changed by the voltage applied to the DBD device (for direct application) or by the amount of ozone added to the exhaust gas (for indirect application). In both cases, NO was easily oxidized to NO2, and the change in NO2 content largely affected the NOx removal performance of the catalytic reactor placed downstream, where both NO and NO2 were reduced to N2 in the presence of ammonia as the reducing agent. The experiments were primarily concerned with the effect of reaction temperature on the catalytic NOx reduction at various NO2 contents. The direct and indirect applications of DBD were found to remarkably improve the catalytic NOx reduction, especially at low temperatures. 展开更多
关键词 dielectric barrier discharge OZONE catalytic reduction nitrogen oxides
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Catalyst-Packed Non-Thermal Plasma Reactor for Removal of Nitrogen Oxides 被引量:4
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作者 V.Ravi YoungSunMok +1 位作者 B.S.Rajanikanth Ho-ChulKang 《Plasma Science and Technology》 SCIE EI CAS CSCD 2003年第1期1603-1608,共6页
A single-stage plasma-catalytic reactor in which catalytic materials werepacked was used to remove nitrogen oxides. The packing material was scoria being made of variousmetal oxides including Al_2O_3, MgO, TiO_2, etc.... A single-stage plasma-catalytic reactor in which catalytic materials werepacked was used to remove nitrogen oxides. The packing material was scoria being made of variousmetal oxides including Al_2O_3, MgO, TiO_2, etc. Scoria was able to act not only as dielectricpellets but also as a catalyst in the presence of reducing agent such as ethylene and ammonia.Without plasma discharge, scoria did not work well as a catalyst in the temperature range of 100 ℃to 200 ℃, showing less than 10% of NOx removal efficiency. When plasma is produced inside thereactor, the NOx removal efficiency could be increased to 60% in this temperature range. 展开更多
关键词 plasma CATALYST SCORIA nitrogen oxides REMOVAL
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A New Approach for Removal of Nitrogen Oxides from Synthetic Gas-streams under High Concentration of Oxygen in Biofilters 被引量:3
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作者 ShaoBinHUANG JuGuangZHANG HePingHU YueSITU 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第4期505-508,共4页
The potential of using denitrifying and nitrifying concurrent biofilters for the removal of nitrogen oxides from synthetic gas streams was studied under the condition of high oxygen concentration. It was found that ... The potential of using denitrifying and nitrifying concurrent biofilters for the removal of nitrogen oxides from synthetic gas streams was studied under the condition of high oxygen concentration. It was found that more than 85% of nitric oxide was removed from synthetic combustion gas-streams which contained 20% oxygen and 350 μL/L NO, with a residence time of 60 seconds. In the process, it was found that the existing of oxygen showed no evident negative effect on the efficiency of nitrogen removal. 展开更多
关键词 BIOFILTER nitrogen oxides nitrification denitrification aerobic.
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Nitrogen doped tin oxide nanostructured catalysts for selective electrochemical reduction of carbon dioxide to formate 被引量:3
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作者 Qiankun Li Zhuo Wang +2 位作者 Miao Zhang Pengfei Hou Peng Kang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第5期825-829,共5页
Tin/tin oxide materials are key electrocatalysts for selective conversion of CO;to formate/formic acid.Herein we report a tin oxide material with nitrogen doping by using ammonia treatment at elevated temperature. The... Tin/tin oxide materials are key electrocatalysts for selective conversion of CO;to formate/formic acid.Herein we report a tin oxide material with nitrogen doping by using ammonia treatment at elevated temperature. The N doped material demonstrated enhanced electrocatalytic CO;reduction activity, showing high Faradaic efficiency(90%) for formate at -0.65 V vs. RHE with partial current density of 4 mA/cm;.The catalysis was contributed to increased electron negativity of N atom compared to O atom. Additionally, the N-doped catalyst demonstrates sulfur tolerance with retained formate selectivity. The analysis after electrolysis shows that the catalyst structure partially converts to metallic Sn, and thus the combined Sn/N-SnO;is the key for the active CO;catalysis. 展开更多
关键词 CO2 reduction ELECTROCATALYSIS FORMATE Tin oxide nitrogen doping
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Removal of Nitrogen Oxides in Diesel Engine Exhaust by Plasma Assisted Molecular Sieves 被引量:3
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作者 B S Rajanikanth, V RaviDept. of High Voltage Engineering, Indian Institute of Science, Bangalore 560012,INDIA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2002年第4期1399-1406,共8页
This paper reports the studies conducted on removal of oxides ofnitrogen (NOx) from diesel engine exhaust using electrical dischargeplasma combined with adsorbing materials such as molecular sieves.This study is being... This paper reports the studies conducted on removal of oxides ofnitrogen (NOx) from diesel engine exhaust using electrical dischargeplasma combined with adsorbing materials such as molecular sieves.This study is being reported for the first time. The exhaust is takenfrom a diesel engine of 6 kW under no load conditions. Thecharacteristic behavior of a pulse energized dielectric barrierdischarge reactor in the diesel exhaust treatment is reported. TheNOx removal was not significant (36/100) when the reactor without anypacking was used. 展开更多
关键词 diesel engine exhaust nitrogen oxides REMOVAL electrical discharge plasma
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The effects of nitrogen fertilizer application on methane and nitrous oxide emission/uptake in Chinese croplands 被引量:18
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作者 SUN Bin-feng ZHAO Hong +2 位作者 LU Yi-zhong Lü Fei WANG Xiao-ke 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第2期440-450,共11页
The application of nitrogen(N) fertilizer to increase crop yields has a significant influence on soil methane(CH_4) and nitrous oxide(N_2O) emission/uptake.A meta-analysis was carried out on the effect of N appl... The application of nitrogen(N) fertilizer to increase crop yields has a significant influence on soil methane(CH_4) and nitrous oxide(N_2O) emission/uptake.A meta-analysis was carried out on the effect of N application on(i) CH_4 emissions in rice paddies,(ii) CH_4 uptake in upland fields and(iii) N_2O emissions.The responses of CH_4 emissions to N application in rice paddies were highly variable and overall no effects were found.CH_4 emissions were stimulated at low N application rates(〈100 kg N ha^(-1)) but inhibited at high N rates(〉200 kg N ha^(-1)) as compared to no N fertilizer(control).The response of CH_4 uptake to N application in upland fields was 15%lower than control,with a mean CH_4 uptake factor of-0.001 kg CH_4-C kg^(-1) N.The mean N_2O emission factors were 1.00 and 0.94%for maize(Zea mays) and wheat(Triticum aestivum),respectively,but significantly lower for the rice(Oryza sativa)(0.51%).Compared with controls,N addition overall increased global warming potential of CH_4 and N_2O emissions by 78%.Our result revealed that response of CH_4 emission to N input might depend on the CH_4concentration in rice paddy.The critical factors that affected CH_4 uptake and N_2O emission were N fertilizer application rate and the controls of CH_4 uptake and N_2O emission.The influences of application times,cropping systems and measurement frequency should all be considered when assessing CH_4 and N_2O emissions/uptake induced by N fertilizer. 展开更多
关键词 nitrogen fertilizer methane nitrous oxide global warming potential emission factor
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A comparison between high temperature catalytic and persulfate oxidation for the determination of total dissolved nitrogen in natural waters
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作者 Tiantian Ge Xue Yang +1 位作者 Shan Jiang Liju Tan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第4期41-49,共9页
Total dissolved nitrogen(TDN) is an important parameter for assessing the nutrient cycling and status of natural waters.The accurate determination of TDN in natural waters is essential for assessing its contents and d... Total dissolved nitrogen(TDN) is an important parameter for assessing the nutrient cycling and status of natural waters.The accurate determination of TDN in natural waters is essential for assessing its contents and distinguishing different forms of nitrogen in the water.The TDN in various systems has been largely documented,and the concentrations of TDN are usually obtained using high-temperature catalytic(HTC) or persulfate oxidation(PO).However,the accuracy of these methods and their suitability for all types of natural waters are still unclear.To explore both methods in-depth,assorted samples were tested,including eight solutions composed of nitrogen-containing compounds(3 dissolved inorganic nitrogen fractions:NO_(3)^(-),NO_(2)^(-)and NH_(4)^(+);5 organic compounds:EDTA-2Na,vitamin B1,vitamin B12,amino acids,and urea) and 105 natural waters which were collected from an open ocean(Northwest Pacific Ocean,28),a marginal sea(Yellow Sea,34),an estuary(Huanghe River mouth,31),rivers(Huanghe River,4;Licun River,4),and precipitations(4 samples).The results showed that heterocycles and molecular dimensions had certain effects on the oxidation efficiency of the PO method but had little effect on HTC.There was no significant difference between the two methods for natural waters,but HTC was more suitable for deep-sea samples with low TDN concentrations(less than 10 μmol/L) and low organic activity.Overall,HTC has a relatively simple measurement process,a high degree of automation,and low error.Therefore,HTC can be recommended to determine the TDN of samples in freshwater and seawater. 展开更多
关键词 total dissolved nitrogen high-temperature catalytic persulfate oxidation natural waters
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Spotlights on immunological effects of reactive nitrogen species: When inflammation says nitric oxide 被引量:3
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作者 Andrea Predonzani Bianca Calì +1 位作者 Andrielly HR Agnellini Barbara Molon 《World Journal of Experimental Medicine》 2015年第2期64-76,共13页
Over the last decades, nitric oxide(NO) has been definitively recognised as one of the key players involved in immunity and inflammation. NO generation was originally described in activated macrophages, which still re... Over the last decades, nitric oxide(NO) has been definitively recognised as one of the key players involved in immunity and inflammation. NO generation was originally described in activated macrophages, which still represent the prototype of NO-producing cells. Notwithstanding, additional cell subsets belonging to both innate and adaptive immunity have been documented to sustain NO propagation by means of the enzymatic activity of different nitric oxide synthase isoforms. Furthermore, due to its chemical characteristics, NO could rapidly react with other free radicals to generate different reactive nitrogen species(RNS), which have been intriguingly associated with many pathological conditions. Nonetheless, the plethora of NO/RNS-mediated effects still remains extremely puzzling. The aim of this manuscript is to dig into the broad literature on the topic to provide intriguing insights on NO-mediated circuits within immune system. We analysed NO and RNS immunological clues arising from their biochemical properties, immunomodulatory activities and finally dealing with their impact on different pathological scenarios with far prompting intriguing perspectives for their pharmacological targeting. 展开更多
关键词 NITRIC oxide Reactive nitrogen species POST-TRANSLATIONAL modification IMMUNE cells IMMUNE DISEASES
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Nano-Ferric Oxide Embedded in Graphene Oxide:High-performance Electrocatalyst for Nitrogen Reduction at Ambient Condition 被引量:4
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作者 Fei Wang Lixue Xia +3 位作者 Xin Li Weixiang Yang Yan Zhao Jian Mao 《Energy & Environmental Materials》 SCIE CSCD 2021年第1期88-94,共7页
Nitrogen(N_(2))fixation at ambient condition by electrochemical N_(2)reduction reaction(NRR)is energy-efficient and eco-friendly as compared to the traditional Harber–Bosch process,but it is extremely challenging.Dev... Nitrogen(N_(2))fixation at ambient condition by electrochemical N_(2)reduction reaction(NRR)is energy-efficient and eco-friendly as compared to the traditional Harber–Bosch process,but it is extremely challenging.Development and design of high-performance NRR electrocatalysts are indispensable to achieve the goal.In this work,a strongly coupled hybrid of nano-Fe3O4 with reduced graphene oxide(rGO)is synthesized via an in situ redox hydrothermal approach,and the synthesized Fe_(3)O_(4)@r GO hybrid has excellent activity,selectivity,and stability as an NRR catalyst.The NH_(3) yield rate of 28.01μg h^(-1)mg^(-1)at-0.3 V and the Faradaic efficiency(FE)of 19.12%at-0.1 V are obtained in 0.1 M Na_(2)SO_(4) solutions at ambient conditions.The superior NRR performance is attributed to the chemical coupling effect between r GO and nano-Fe_(3)O_(4) particles,which leads to the enhancement of the binding affinity to N_(2) molecules,improvement of the conductivity,and lowering the free energy of reaction for the limiting reaction step.This work provides a facile route in fabricating hybrid NRR catalysts with superior performance and shed lights on the reaction mechanism with theoretical mechanistic calculations. 展开更多
关键词 density functional theory graphene nano-ferric oxide nitrogen reduction reaction
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Iron Oxide Nanoparticles Induced Oxidative Damage in Peripheral Blood Cells of Rat 被引量:1
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作者 Usha Singh Gaharwar Paulraj R 《Journal of Biomedical Science and Engineering》 2015年第4期274-286,共13页
Nanotechnology is a rapidly growing field that has elicited much concern due to a variety of applications in different fields such as industry, medicine, and cosmetics. These developments increase the concern among th... Nanotechnology is a rapidly growing field that has elicited much concern due to a variety of applications in different fields such as industry, medicine, and cosmetics. These developments increase the concern among the general population. Hence, there is an urgent need to explore the possible human health effects of these nanomaterials. The present study is aimed to evaluate the cytotoxic and genotoxic effects of iron oxide nanoparticles (IONPs) in-vivo. In order to study the toxic effects, Wistar rats were administered intravenously with various doses of IONPs (Fe2O3) through caudal vein once in a week for 28 days, and various biochemical assays such as antioxidant enzymes activity (SOD, CAT, and GSH), lipid peroxidation, DNA damage and hematological parameters were evaluated. Genotoxicity was evaluated by comet assay and oxidative stress was measured by anti-oxidant enzymes. The results reveal that IONPs alter hematological factor such as RBC counts, WBC counts, neutrophils, monocytes and hemoglobin. A dose-dependent inhibition (p < 0.05) of antioxidant enzymes was found, and meanwhile the level of MDA elevated significantly (p < 0.05) in IONPs treated groups in dose-dependent manner;however comet assay results indicate that IONPs did not induce any significant DNA damage. The present study concluded that IONP affects inflammatory response, which induces the oxidative stress and may adversely affect the cellular function. 展开更多
关键词 oxidATIVE Stress Iron oxide Nanoparticles ANTIoxidANT ENZYMES GENOTOXICITY PERIPHERAL blood Cells
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STUDIES ON TBP-NO_x——A NEW OXIDIZING AGENT PREPARED FROM NITROGEN OXIDES 被引量:1
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作者 Shen Shong ZHANG Ren Zhong QIAO +1 位作者 Qing Zhi ZHANG Fu Gui LU 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第11期877-878,共2页
Nitrogen oxides(NO_2 and NO)are absorbed by tributyl phosphorate(TBP)to fom a new complex mixture of TBP-NO_x. which is used as a selective oddizing agent to oxidize benzylalcohols to corresponding sldehydes or ketone... Nitrogen oxides(NO_2 and NO)are absorbed by tributyl phosphorate(TBP)to fom a new complex mixture of TBP-NO_x. which is used as a selective oddizing agent to oxidize benzylalcohols to corresponding sldehydes or ketones In high yield. In the reaction process, nitrogen oxides are llberated mildly and mainly reduced to nitrogen, while tributyl phosphorate is recovered end recycled. 展开更多
关键词 NO 目血 A NEW oxidIZING AGENT PREPARED FROM nitrogen oxideS STUDIES ON TBP-NO_x AGENT TBP
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Evaluation of Nitrogen Oxides Pollution in Takamatsu and Utazu Area in Kagawa Prefecture, Japan 被引量:1
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作者 Shoko Murakami Noriko Sakano +2 位作者 Sakano Suna Fumiyuki Asakawa Nobuyuki Miyatake 《Journal of Environmental Protection》 2011年第2期194-197,共4页
We evaluate nitrogen oxides pollution in Takamatsu and Utazu area in Kagawa prefecture, Japan. Annually observations for nitrogen oxides (nitrogen dioxide;NO2, nitric oxide;NO) (1990-2007) were obtained from data base... We evaluate nitrogen oxides pollution in Takamatsu and Utazu area in Kagawa prefecture, Japan. Annually observations for nitrogen oxides (nitrogen dioxide;NO2, nitric oxide;NO) (1990-2007) were obtained from data base of Kagawa prefecture, Japan. Changes in NO2 and NO in Takamatsu and Utazu area were evaluated and compared. In 2007, NO2, NO and NO2 + NO (ppm) in Takamatsu area were higher than those in Utazu area. However, NO2 /NO + NO2 in Takamatsu area was lower than that in Utazu area. From 1990 to 2007, mean of NO2 in a day over the level of 0.06 ppm was 30 days in Takamatsu area and only one day in Utazu area. Mean of NO2, NO and NO2 + NO was significantly higher and NO2/NO + NO2 was lower in Takamatsu area than that in Utazu area. In addition, NO2, NO and NO2 + NO were negatively correlated and NO2/NO + NO2 was positively correlated with years (1990-2007) in Takamatsu area. The level of nitrogen oxides pollution in Utazu area was lower than Takamatsu area. Further observation is required for preventing nitrogen oxides pollution in Kagawa prefecture, Japan. 展开更多
关键词 nitrogen oxideS NO2 NO Utazu Area Takamatsu Area
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Nitrogen Dioxide Fumigation for Microbial Control on Unshelled Peanuts* 被引量:1
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作者 Sookyung Oh Rippy Singh Yong-Biao Liu# 《Agricultural Sciences》 2020年第12期1159-1169,共11页
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 ... 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 NO<sub>2</sub> due to NO reaction with oxygen and NO<sub>2</sub> has antimicrobial property. Therefore, NO fumigation has potential to control both pests and pathogens. In this study, we evaluated antimicrobial effects of NO<sub>2</sub> fumigation on unpasteurized unshelled peanuts. Peanuts were fumigated with 0.3%, 1.0%, and 3.0% NO<sub>2</sub> for three days at 25<span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#730;</span></span></span>C by injecting NO gas into glass jars to react with O<sub>2</sub> 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<span style="white-space:nowrap;"><sup><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#8482;</span></span></sup></span> rapid enumeration test based on oxygen depletion on culture medium. All three NO<sub>2</sub> fumigation treatments showed significant antibacterial and antifungal effects on intact peanuts as well as on cracked peanuts with complete inhibition with 3.0% NO<sub>2</sub>. Fumigation did not have obvious effects on appearance of skinned peanut kernels. These results suggested that NO<sub>2</sub> fumigation has potential to control microbes on stored products, and NO fumigation with the combination of NO and NO<sub>2</sub> has potential to control both insects and microbes on stored products. 展开更多
关键词 nitrogen Dioxide Nitric oxide POSTHARVEST FUMIGATION Microbes Peanuts
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Nitrosation Reaction Without Nitrogen Oxide Waste Gas Emission and Its Engineering Practice 被引量:1
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作者 陈春光 冯亚青 +1 位作者 牛伟玮 陈学玺 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第4期442-446,共5页
The gas-liquid phase equilibrium is used in controlling the nitrosation reaction process. Decomposition of nitrous acid and oxidation side reaction are suppressed in a closed reaction system. The system pressure is us... The gas-liquid phase equilibrium is used in controlling the nitrosation reaction process. Decomposition of nitrous acid and oxidation side reaction are suppressed in a closed reaction system. The system pressure is used as the criterion of the end of reaction, avoiding excessive feeding and reducing the decomposition of nitrous acid. The head space of the reactor is used as the gas buffer, stabilizing the feeding fluctuations and inhibiting the side reaction, decomposition of nitrous acid. Nitrogen oxide concentration is controlled at the minimum level. Thus the zero release of nitrogen oxide waste gas can be achieved without using any absorption process. 展开更多
关键词 亚硝化反应 废气排放量 氮氧化物 工程实践 亚硝酸 反应过程 平衡控制 反应体系
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Could natural phytochemicals be used to reduce nitrogen excretion and excreta‑derived N_(2)O emissions from ruminants?
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作者 Yuchao Zhao Ming Liu +1 位作者 Linshu Jiang Leluo Guan 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期490-508,共19页
Ruminants play a critical role in our food system by converting plant biomass that humans cannot or choose not to consume into edible high-quality food.However,ruminant excreta is a significant source of nitrous oxide... Ruminants play a critical role in our food system by converting plant biomass that humans cannot or choose not to consume into edible high-quality food.However,ruminant excreta is a significant source of nitrous oxide(N_(2)O),a potent greenhouse gas with a long-term global warming potential 298 times that of carbon dioxide.Natural phytochemicals or forages containing phytochemicals have shown the potential to improve the efficiency of nitrogen(N)utilization and decrease N_(2)O emissions from the excreta of ruminants.Dietary inclusion of tannins can shift more of the excreted N to the feces,alter the urinary N composition and consequently reduce N_(2)O emissions from excreta.Essential oils or saponins could inhibit rumen ammonia production and decrease urinary N excretion.In grazed pastures,large amounts of glucosinolates or aucubin can be introduced into pasture soils when animals consume plants rich in these compounds and then excrete them or their metabolites in the urine or feces.If inhibitory compounds are excreted in the urine,they would be directly applied to the urine patch to reduce nitrification and subsequent N_(2)O emissions.The phytochemicals’role in sustainable ruminant production is undeniable,but much uncertainty remains.Inconsistency,transient effects,and adverse effects limit the effectiveness of these phytochemicals for reducing N losses.In this review,we will identify some current phytochemicals found in feed that have the potential to manipulate ruminant N excretion or mitigate N_(2)O production and deliberate the challenges and opportunities associated with using phytochemicals or forages rich in phytochemicals as dietary strategies for reducing N excretion and excreta-derived N_(2)O emissions. 展开更多
关键词 nitrogen metabolism Nitrous oxide Plant bioactive compounds RUMINANT Urine patches
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Hollow cobalt oxide nanoparticles embedded in nitrogen-doped carbon nanosheets as an efficient bifunctional catalyst for Zn–air battery 被引量:5
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作者 Yuhui Tian Li Xu +6 位作者 Jian Bao Junchao Qian Huaneng Su Huaming Li Haidong Gu Cheng Yan Henan Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第6期59-66,共8页
Rational design of low-cost, highly electrocatalytic activity, and stable bifunctional electrocatalysts for oxygen reduction reaction(ORR) and oxygen evolution reaction(OER) has been a great significant for metal–air... Rational design of low-cost, highly electrocatalytic activity, and stable bifunctional electrocatalysts for oxygen reduction reaction(ORR) and oxygen evolution reaction(OER) has been a great significant for metal–air batteries. Herein, an efficient bifunctional electrocatalyst based on hollow cobalt oxide nanoparticles embedded in nitrogen-doped carbon nanosheets(Co/N-Pg) is fabricated for Zn–air batteries. A lowcost biomass peach gum, consisting of carbon, oxygen, and hydrogen without other heteroatoms, was used as carbon source to form carbon matrix hosting hollow cobalt oxide nanoparticles. Meanwhile, the melamine was applied as nitrogen source and template precursor, which can convert to carbon-based template graphitic carbon nitride by polycondensation process. Owing to the unique structure and synergistic effect between hollow cobalt oxide nanoparticles and Co-N-C species, the proposal Co/N-Pg catalyst displays not only prominent bifunctional electrocatalytic activities for ORR and OER, but also excellent durability. Remarkably, the assembled Zn–air battery with Co/N-Pg air electrode exhibited a low discharge-charge voltage gap(0.81 V at 50 mA cm^-2) and high peak power density(119 mW cm^-2) with long-term cycling stability. This work presents an effective approach for engineering transition metal oxides and nitrogen modified carbon nanosheets to boost the performance of bifunctional electrocatalysts for Zn–air battery. 展开更多
关键词 Zn-air batteries OXYGEN reduction REACTION OXYGEN evolution REACTION nitrogen-DOPED carbon NANOSHEETS Cobalt oxides
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Cu,N codoped carbon nanosheets encapsulating ultrasmall Cu nanoparticles for enhancing selective 1,2-propanediol oxidation
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作者 Yonghai Feng Min Yu +2 位作者 Minjia Meng Lei Liu Dewei Rao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期27-35,共9页
In the selective oxidation of biomass-based 1,2-propanediol(PDO)with oxygen as the terminal oxidant,it is challenging to improve the lactic acid(LA)selectivity for nonnoble metal nanoparticles(NPs)due to their limited... In the selective oxidation of biomass-based 1,2-propanediol(PDO)with oxygen as the terminal oxidant,it is challenging to improve the lactic acid(LA)selectivity for nonnoble metal nanoparticles(NPs)due to their limited oxygen reduction rate and easy C-C cleavage.Given the high economic feasibility of nonnoble metals,i.e.,Cu,in this work,copper and nitrogen codoped porous carbon nanosheets encapsulating ultrafine Cu nanoparticles(Cu@Cu-N-C)were developed to realize highly selective of PDO oxidation to LA.The carbon-encapsulated ultrasmall Cu^(0)NPs in Cu@Cu-N-C have high PDO dehydrogenation activity while N-coordinated Cu(Cu-N)sites are responsible for the high oxygen reduction efficacy.Therefore,the performance of catalytic PDO conversion to LA is optimized by a proposed pathway of PDO→hydroxylacetone→lactaldehyde→LA.Specifically,the enhanced LA selectivity is 88.5%,and the PDO conversion is up to 75.1%in an O_(2)-pressurized reaction system(1.0 MPa O_(2)),superior to other Cu-based catalysts,while in a milder nonpressurized system(O_(2)flow rate of 100 mL min-1),a remarkable LA selectivity(94.2%)is obtained with 39.8%PDO conversion,2.2 times higher than that of supported Au nanoparticles(1%Au/C).Moreover,carbon encapsulation offers Cu@Cu-N-C with strong leaching resistance for better recycling. 展开更多
关键词 Selective oxidation Copper and nitrogen doped carbon 1 2-PROPANEDIOL Ultrasmall Cu nanoparticles Lactic acid
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Unveiling the silent link:Normal-tension glaucoma's enigmatic bond with cardiac blood flow
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作者 Prasanna Venkatesh Ramesh Arvind Kumar Morya +5 位作者 Ajanya K Aradhya Pavithra Pannerselvam Sai Thaejesvi Gopalakrishnan Shruthy Vaishali Ramesh Aji Kunnath Devadas Navaneeth Krishna 《World Journal of Cardiology》 2024年第1期10-15,共6页
This comprehensive review embarks on a captivating journey into the complex relationship between cardiology and normal-tension glaucoma(NTG),a condition that continues to baffle clinicians and researchers alike.NTG,ch... This comprehensive review embarks on a captivating journey into the complex relationship between cardiology and normal-tension glaucoma(NTG),a condition that continues to baffle clinicians and researchers alike.NTG,characterized by optic nerve damage and visual field loss despite normal intraocular pressure,has long puzzled clinicians.One emerging perspective suggests that alterations in ocular blood flow,particularly within the optic nerve head,may play a pivotal role in its pathogenesis.While NTG shares commonalities with its high-tension counterpart,its unique pathogenesis and potential ties to cardiovascular health make it a fascinating subject of exploration.It navigates through the complex web of vascular dysregulation,blood pressure and perfusion pressure,neurovascular coupling,and oxidative stress,seeking to uncover the hidden threads that tie the heart and eyes together in NTG.This review explores into the intricate mechanisms connecting cardiovascular factors to NTG,shedding light on how cardiac dynamics can influence ocular health,particularly in cases where intraocular pressure remains within the normal range.NTG's enigmatic nature,often characterized by seemingly contradictory risk factors and clinical profiles,underscores the need for a holistic approach to patient care.Drawing parallels to cardiac health,we examine into the shared vascular terrain connecting the heart and the eyes.Cardiovascular factors,including systemic blood flow,endothelial dysfunction,and microcirculatory anomalies,may exert a profound influence on ocular perfusion,impacting the delicate balance within the optic nerve head.By elucidating the subtle clues and potential associations between cardiology and NTG,this review invites clinicians to consider a broader perspective in their evaluation and management of this elusive condition.As the understanding of these connections evolves,so too may the prospects for early diagnosis and tailored interventions,ultimately enhancing the quality of life for those living with NTG. 展开更多
关键词 Normal tension glaucoma Vascular dysregulation Ocular blood flow blood pressure Perfusion pressure oxidative stress
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