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Microstructure Evolution Characteristics and Mechanical Properties of a Novel Nitrogenous Nickel-Based Deposited Metal from Gas Metal Arc Welded State to Heat-Treated State
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作者 Wang Yingdi Zhang Guiqing +2 位作者 Yang Taisen Liang Xuewei Su Yunhai 《稀有金属材料与工程》 北大核心 2025年第12期3010-3023,共14页
A novel nitrogenous nickel-based deposited metal was prepared by gas metal arc welding.Subsequently,solid solution treatment as well as solution and aging treatments were conducted on the prepared metal to study the e... A novel nitrogenous nickel-based deposited metal was prepared by gas metal arc welding.Subsequently,solid solution treatment as well as solution and aging treatments were conducted on the prepared metal to study the evolution of microstructure and tensile properties at different states.Results show that the high-temperature tensile strength of the deposited metal exhibits good performance after the addition of W and N.The grain size of the sample is large,and petal-like Laves phase appears at the grain boundaries.After solid solution treatment,the grain size decreases,and the Laves phase disappears.However,both the yield strength and elongation of the deposited metal decrease.The grain size of the samples after solid solution and aging treatment is more uniform,nanoscale M(C,N)phases are precipitated within the crystals,and M_(23)C_(6) phase forms at grain boundaries.The yield strength and ultimate tensile strength of this sample are higher than those of the other samples,but its plasticity is the lowest.The main deformation mechanism is the unit dislocation a/2<110>cutting the precipitation phase. 展开更多
关键词 nitrogenous deposited metals microstructure tensile performance DISLOCATION
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Effect of Arbuscular Mycorrhiza on the Content of Nitrogen and Nitrogenous Matter in Amur Corktree Seedlings 被引量:2
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作者 范继红 高琼 邹原东 《Agricultural Science & Technology》 CAS 2012年第8期1695-1698,共4页
[Objective] This study aimed to explore the effect of arbuscular mycorrhiza on the content of nitrogen and nitrogenous matter in amur corktree(Phellodendron amurense Rupr.)seedlings. [Method] The annual seedlings of... [Objective] This study aimed to explore the effect of arbuscular mycorrhiza on the content of nitrogen and nitrogenous matter in amur corktree(Phellodendron amurense Rupr.)seedlings. [Method] The annual seedlings of Phellodendron amurense Rupr. were inoculated with four arbuscular mycorrhiza fungi in a pot experiment to study the influences of arbuscular mycorrhiza on the content of nitrogen and nitrogenous matter in Phellodendron amurense Rupr. [Result] After inoculation with arbuscular mycorrhiza fungi, the Phellodendron amurense Rupr. seedlings developed arbuscular mycorrhiza, leading to an enhancement of photosynthetic capacity. The leaf nitrogen content of those inoculated with Glomus mosseae increased to 1.28- 1.60 times as compared with the control. The chlorophyll content and chlorophyll a/b ratio were also raised, with an increase over 25% of chlorophyll a content. In addition, IAA content in plants increased to 1.65-2.41 times; and nitrate reductase activity was also enhanced, as well as soluble protein content, 1.67-2.49 times as high as the control, which improved the nitrogen metabolic ability, and promoted the plant growth, as well as the secondary metabolic ability. [Conclusion] This study provides a theoretical basis for the application of arbuscular mycorrhiza on Phellodendron amurense Rupr. 展开更多
关键词 Arbuscular mycorrhiza Phellodendron amurense Rupr. NITROGEN nitrogenous matter CONTENT
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Carbonaceous and nitrogenous disinfection by-product formation in the surface and ground water treatment plants using Yellow River as water source 被引量:8
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作者 Yukun Hou Wenhai Chu Meng Ma 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第7期1204-1209,共6页
This work investigated the formation of carbonaceous and nitrogenous disinfection by-products (C-DBPs, N-DBPs) upon chlorination of water samples collected from a surface water and a ground water treatment plant (S... This work investigated the formation of carbonaceous and nitrogenous disinfection by-products (C-DBPs, N-DBPs) upon chlorination of water samples collected from a surface water and a ground water treatment plant (SWTP and GWTP) where the conventional treatment processes, i.e., coagulation, sedimentation, and filtration were employed. Twenty DBPs, including four trihalomethanes, nine haloacetic acids, seven N-DBPs (dichloroacetamide, trichloroacetamide, dichloroacetonitrile, trichloroacetonitrile, bromochloroace- tonitrile, dibromoacetonitrile and trichloronitromethane), and eight volatile chlorinated compounds (dichloromethane (DCM), 1,2-dichloroethane, tetrachloroethylene, chlorobenzene, 1,2-dichlorobenzene, 1,4-dichlorobenzene, 1,2,3-trichlorobenzene and 1,2,4- trichlorobenzene) were detected in the two WTPs. The concentrations of these contaminants were all below their corresponding maximum contamination levels (MCLs) regulated by the Standards for Drinking Water Quality of China (GB5749-2006) except for DCM (17.1 ~tg/L detected vs. 20 μg/L MCL). The SWTP had much higher concentrations of DBPs detected in the treated water as well as the DBP formation potentials tested in the filtered water than the GWTP, probably because more precursors (e.g., dissolved organic carbon, dissolved organic nitrogen) were present in the water source of the SWTE 展开更多
关键词 carbonaceous disinfection by-products nitrogenous disinfection by-products formation potential free chlorine watertreatment plant
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Yield and Quality of Forage Oat (<i>Avena sativa</i>L.) Cultivars as Affected by Seed Inoculation with Nitrogenous Strains 被引量:4
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作者 Muhammad Saleem M. Shahid Ibni Zamir +7 位作者 Ihtishamul Haq M. Zahid Irshad M. Kamran Khan M. Asim Qamaruz Zaman Ihtisham Ali Aman Khan Saeedur Rehman 《American Journal of Plant Sciences》 2015年第19期3251-3259,共9页
Nitrogen availability can be enhanced with the application of nitrogen fixing bacteria and it may be helpful in increasing forage yield and improving quality of oat. Therefore, a field trial to evaluate the effect of ... Nitrogen availability can be enhanced with the application of nitrogen fixing bacteria and it may be helpful in increasing forage yield and improving quality of oat. Therefore, a field trial to evaluate the effect of seed inoculation with nitrogen fixing bacteria on forage yield and quality of oat was carried out at Agronomic Research Area, University of Agriculture, Faisalabad during Rabi season 2013-14. The experiment was laid out in Randomized Complete Block Design (RCBD) with factorial arrangements using three replications. The experiment was comprised of two integrated approaches. The first approach was oat cultivars consisting of four treatments, V1 (AVON), V2 (S-2000), V3 (S-2011) and V4 (PD2LV65) and the second approach was seed inoculation consisting of three treatments, S0 (control), S1 (Azotobacter spp.), S2 (Azospirillum spp.). Fisher’s analysis of variance technique was used for statistically interpretation of data by using least significant difference (LSD) test at 5% level of probability. Nitrogen fixing bacteria significantly affect the germination count (m2), plant height (cm), number of tillers (m2), number of leaves per tiller, leaf area per tiller (cm2), green forage yield (t·ha-1) and dry matter yield (t ha-1). The maximum green forage yield (85.2 t·ha-1), dry matter yield (14.1 t ·ha-1) and crude protein (11.5%) were recorded where Azotobacter inoculation was applied. The interaction between cultivars and nitrogenous strains was significant for green forage yield (t·ha-1), dry matter yield (t·ha-1) and crude protein (%). Conclusion showed that cultivar Sargodha-2011 which was inoculated with Azotobacter spp. gave higher forage yield of good quality. 展开更多
关键词 Oat CULTIVARS nitrogenous STRAINS Quality and FORAGE Yield
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Nitrogenous and carbonaceous aerosols in PM_(2.5) and TSP during pre-monsoon:Characteristics and sources in the highly polluted mountain valley 被引量:1
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作者 Hemraj Bhattarai Lekhendra Tripathee +5 位作者 Shichang Kang Pengfei Chen Chhatra Mani Sharma Kirpa Ram Junming Guo Maheswar Rupakheti 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第5期10-24,共15页
This study reports for the first time a comprehensive analysis of nitrogenous and carbona-ceous aerosols in simultaneously collected PM_(2.5) and TSP during pre-monsoon(March-May 2018)from a highly polluted urban Kath... This study reports for the first time a comprehensive analysis of nitrogenous and carbona-ceous aerosols in simultaneously collected PM_(2.5) and TSP during pre-monsoon(March-May 2018)from a highly polluted urban Kathmandu Valley(KV)of the Himalayan foothills.The mean mass concentration of PM_(2.5)(129.8 μg/m^(3))was only-25%of TSP mass(558.7 μg/m^(3))indicating the dominance of coarser mode aerosols.However,the mean concentration as well as fractional contributions of water-soluble total nitrogen(WSTN)and carbonaceous species reveal their predominance in find-mode aerosols.The mean mass concentration of WSTN was 17.43±4.70 μg/m^(3)(14%)in PM_(2.5) and 24.64±8.07 μg/m^(3)(5%)in TSP.Moreover,the fractional contribution of total carbonaceous aerosols(TCA)is much higher in PM_(2.5)(~34%)than that in TSP(~20%).The relatively low OC/EC ratio in PM_(2.5)(3.03±1.47)and TSP(4.64±1.73)suggests fossil fuel combustion as the major sources of carbonaceous aerosols with contributions from secondary organic aerosols.Five-day air mass back trajectories sim-ulated with the HYSPLIT model,together with MODIS fire counts indicate the influence of local emissions as well as transported pollutants from the Indo-Gangetic Plain region to the south of the Himalayan foothills.Principal component analysis(PCA)also suggests a mixed contribution from other local anthropogenic,biomass burning,and crustal sources.Our re-sults highlight that it is necessary to control local emissions as well as regional transport while designing mitigation measures to reduce the KV's air pollution. 展开更多
关键词 nitrogenous aerosol Carbonaceous aerosols Major ions Particulate pollution Kathmandu Valley(KV)
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Effects of a Combined Application of Nitrogenous and Phosphorus Fertilizers on the Growth of Pinus radiata
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作者 Jianshe HE Qimei KANG +6 位作者 Hua YANG Xinwei ZHU Xiaoqiang TANG Ying KANG Junfang REN Yonghong TANG Qianli LIU 《Agricultural Biotechnology》 CAS 2019年第4期126-128,共3页
In the arid valley of the upper reaches of the Minjiang river,combined application tests of nitrogenous and phosphorus fertilizers were conducted to the 1-year-old seedlings of Pinus radiate to investigate the appropr... In the arid valley of the upper reaches of the Minjiang river,combined application tests of nitrogenous and phosphorus fertilizers were conducted to the 1-year-old seedlings of Pinus radiate to investigate the appropriate amount of fertilization,so as to provide bases of fertilization management of young P.radiate in the arid val-ley.Different combined application amounts of nitrogenous and phosphorus were studied based on the randomized blocks design.The results showed that in comparing 3 treatment groups with the control,the first and second treatments significantly increased the ground diameter and height of P.radiate,while the third treatment merely significantly increased the ground diameter.Under the conditions of this study,the recommended fertilization amount was 30 g of urea and 150 g of calcium superphosphate per plant for the one-year-old P.radiate. 展开更多
关键词 nitrogenous and PHOSPHORUS fertilizers COMBINED FERTILIZATION PINUS RADIATA GROWTH Influence
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Effects of typical nitrogenous compounds on trihalomethanes formation and chlorine demand during drinking water chlorination
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作者 陶辉 赵志伟 +4 位作者 陈卫 刘成 李星 王花平 李圭白 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第3期303-307,共5页
Glycine(Gly),cysteine(Cys),aspartic acid(Asp),leucine(Leu),lysine(Lys),and methyl amine(MA) were chosen as typical nitrogenous compounds,and the effects of them on trihalomethanes (THMs) formation and chlorine demand ... Glycine(Gly),cysteine(Cys),aspartic acid(Asp),leucine(Leu),lysine(Lys),and methyl amine(MA) were chosen as typical nitrogenous compounds,and the effects of them on trihalomethanes (THMs) formation and chlorine demand were performed on filtrated water. Results show that the nitrogenous compounds enhance THMs formation,and the increased levels are controlled by characteristics and the concentration of nitrogenous compounds. The increase in THMs formation follows the order of Asp(126 μg/L)>Cys(119 μg/L)>MA(106 μg/L)>Lys(97 μg/L)≈Gly(96 μg/L)>Leu(80 μg/L)(while nitrogenous compounds=1.0 mg/L,and background THMs=60 μg/L). The increase in chlorine demand is approximately proportionate to the content of nitrogenous compounds,which illustrates that the increase is mainly caused by the reaction of nitrogenous compounds with chlorine. And the increase in chlorine demand follows the order of Cys(27.8 mg/L)>Asp(22.6 mg/L)=Gly(22.6 mg/L)>Lys(21.6 mg/L)>MA(14.1 mg/L)>Leu(11.8 mg/L) (while nitrogenous compounds=1.0 mg/L,and background chorine demand=1.8 mg/L). The mechanisms of nitrogenous compounds enhancing THMs formation are summ the increase of chlorine demand raising THMs formation in reaction of NOM with chlorine,and the THMs formation in chlorination of nitrogenous compounds themselves. 展开更多
关键词 nitrogenous compounds TRIHALOMETHANE chlorine demand
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Effects of Nitrogenous Fertilizer on Pungency of Hot Pepper (Capsicum annuum L.) Fruits
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作者 WANG Jin-ling LV Chang-shan YU Guang-jian 《Journal of Northeast Agricultural University(English Edition)》 CAS 2005年第2期102-104,共3页
The response of pungency of hot pepper fruits nitrogenous fertilizer on was invesigated. The results indicated that nitrogenous fertilizer had a significant effect on the capsaicin content of hot pepper fruits at 35 a... The response of pungency of hot pepper fruits nitrogenous fertilizer on was invesigated. The results indicated that nitrogenous fertilizer had a significant effect on the capsaicin content of hot pepper fruits at 35 and 42 days after flowering;, capsaicin content gradually decreased, while peroxidase activity increased with nitrogenous fertilizer increasing. 展开更多
关键词 capsaicin hot pepper nitrogenous fertilizer peroxidase activity
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Effect of Nitrogenous Fertilizer Treatment on Mineral Metabolism in Grazing Yaks 被引量:3
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作者 SHEN Xiao-yun 《Agricultural Sciences in China》 CAS CSCD 2009年第3期361-368,共8页
To assess the impact of N fertilization on contents of mineral elements in herbage and the effect of increased forage S on the copper metabolism of grazing yaks, study was conducted during the summer grazing season (... To assess the impact of N fertilization on contents of mineral elements in herbage and the effect of increased forage S on the copper metabolism of grazing yaks, study was conducted during the summer grazing season (2005, 2006, and 2007). Pasture replicates (20 ha; n=3 per treatment) received the same fertilizer treatment in each growing season, consisting of i) 90 kg N ha^-1 from quickly available nitrogen, ii) 90 kg N ha^-1 from ammonium nitrate, iii) 90 kg N ha^-1 from ammonium sulfate, and iv) control (no fertilizer). Forage sampling was collected at 60 days intervals following fertilization (10 samples per pasture) for Cu, Mo, Mn, Se, Fe, Zn, Ca, and P. To determine the effect of fertilizer treatment on mineral metabolism in grazing yaks, liver and blood samples were collected at the start and end of the study period in 2005, 2006, and 2007. Ammonium sulfate fertilization increased (P 〈 0.01) forage S concentration. Plant tissue N concentrations were increased by N fertilization, regardless of source in 2005, 2006, and 2007. Yaks grazing S fertilization pastures had lower (P〈0.05) liver and blood Cu concentrations at the end of the study period in 2005, 2006, and 2007, compared with urea, ammonium nitrate, and control. Nominal increases in forage in vitro organic matter digestibility were realized by fertilization, regardless of N source in each year. 展开更多
关键词 yaks nitrogen fertilizer treatment alpine meadow FORAGE mineral element metabolism
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Export of dissolved carbonaceous and nitrogenous substances in rivers of the “Water Tower of Asia” 被引量:1
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作者 Bin Qu Mika Sillanpaa +4 位作者 Shichang Kang Fangping Yan Zhiguo Li Hongbo Zhang Chaoliu Li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第3期53-61,共9页
Rivers are critical links in the carbon and nitrogen cycle in aquatic,terrestrial,and atmospheric environments.Here riverine carbon and nitrogen exports in nine large rivers on the Tibetan Plateau—the"Water Tower of... Rivers are critical links in the carbon and nitrogen cycle in aquatic,terrestrial,and atmospheric environments.Here riverine carbon and nitrogen exports in nine large rivers on the Tibetan Plateau—the"Water Tower of Asia"—were investigated in the monsoon season from 2013 to 2015.Compared with the world average,concentrations of dissolved inorganic carbon(DIC,30.7 mg/L)were high in river basins of the plateau due to extensive topographic relief and intensive water erosion.Low concentrations of dissolved organic carbon(DOC,1.16 mg/L)were likely due to the low temperature and unproductive land vegetation environments.Average concentrations of riverine DIN(0.32 mg/L)and DON(0.35 mg/L)on the Tibetan Plateau were close to the world average.However,despite its predominantly pristine environment,discharge from agricultural activities and urban areas of the plateau has raised riverine N export.In addition,DOC/DON ratio(C/N,~6.5)in rivers of the Tibetan Plateau was much lower than the global average,indicating that dissolved organic carbon in the rivers of this region might be more bioavailable.Therefore,along with global warming and anthropogenic activities,increasing export of bioavailable riverine carbon and nitrogen from rivers of the Tibetan Plateau can be expected in the future,which will possibly influence the regional carbon and nitrogen cycle. 展开更多
关键词 Dissolved carbon Dissolved nitrogen RIVERS The Tibetan Plateau
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Recent advances in photocatalytic C-H amination to nitrogenous structures
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作者 Chunzheng Ma Yuanyuan Chang +6 位作者 Jessie Yang Lu Chen Di Wu Yuyo Go Bin Wang Linlin Shi Bingjie Li 《Green Synthesis and Catalysis》 2026年第1期16-33,共18页
Nitrogen-containing structures represent a significant branch exhibiting remarkable biological activity,surpassing non-nitrogen architectures.Given the vast array of nitrogen-containing compounds and their crucial rol... Nitrogen-containing structures represent a significant branch exhibiting remarkable biological activity,surpassing non-nitrogen architectures.Given the vast array of nitrogen-containing compounds and their crucial role in the pharmaceutical industry,chemists have been motivated to devise efficient,cost-effective,and practical methods for C-N bond formation.Significant advancements have been achieved in this cutting-edge field over the past few decades.This review aims to encapsulate the latest progress in C-N bond formation via the photocatalytic C-H amination process.Initially,we provide a comprehensive introduction to C-H amination transformations.Subsequently,we categorize these photochemical conversions into two parts:intramolecular and intermolecular C-H amination.To elucidate the underlying principles of specific illustrative examples,we have carefully chosen and elaborated on the reaction mechanisms,representative experimental outcomes,and applications. 展开更多
关键词 Photocatalytic transformation C-N formation C-H amination nitrogenous structures
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Under-reporting potential of inoxidizable nitrogenous organic compounds in assessing organic pollution of waters:Underlying mechanisms
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作者 Zhouyan Li Jinxing Ma +3 位作者 Ruobin Dai Yuxiang He Wei Shi Zhiwei Wang 《Fundamental Research》 2025年第5期2180-2186,共7页
Accurate assessment of organic pollution plays a vital role in environmental protection,administration,and legislation.Methodology involving the evaluation of dichromate-based chemical oxygen demand(COD_(Cr))has been ... Accurate assessment of organic pollution plays a vital role in environmental protection,administration,and legislation.Methodology involving the evaluation of dichromate-based chemical oxygen demand(COD_(Cr))has been widely used for assessing organic pollution in water due to convenience,simplicity,and repeatability.Some nitrogenous organic compounds exhibit very low COD_(Cr)/theoretical oxygen demand(ThOD)ratios,which are termed inoxidizable nitrogenous organic compounds(INOCs)in this study.However,not much attention has been paid to their ubiquitous presence and intrinsic properties.Here,we aimed to determine the under-reporting potential of INOCs when assessing organic water pollution via COD_(Cr) and reveal the mechanisms underlying such under-reporting.COD_(Cr) reported only 0%-20%of the theoretical values of short-chain organic amines and pyridine derivatives,thereby posing severe challenges to both the treatment and reclamation of wastewater.Density functional theory calculations revealed that the use of dichromate-based transformation of INOCs to highly stable protonated/ionic forms under acidic conditions may lead to incomplete reactions,resulting in a significant under-reporting potential of INOCs.Our results may serve as a basis for governments,industries,and other stakeholders to respond more effectively to challenges posed by INOCs. 展开更多
关键词 Inoxidizable nitrogenous organic compounds Organic pollution Chemical oxygen demand Water treatment Environmental management
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Solid state reactions of nitrogenous heterocyclic compounds (Ⅱ)——Solid state reactions of indole with carbonyl compounds 被引量:1
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作者 李晓陆 王永梅 +3 位作者 杜大明 文忠 熊国祥 孟继本 《Science China Chemistry》 SCIE EI CAS 1997年第3期270-277,共8页
<正> Solid state Michael addition reaction of indole with α,β-unsaturaled carbonyl compounds was carried out,by which a series of compounds containing three different heterocyclic groups binding to one carbon ... <正> Solid state Michael addition reaction of indole with α,β-unsaturaled carbonyl compounds was carried out,by which a series of compounds containing three different heterocyclic groups binding to one carbon atom were obtained.In the presence of Lewis acid,indole could undergo the solid state condensation reaction with aromatic ketones and aldehydes or quinones.The solid state reaction showed higher selectivity and yield than solution reaction The structures of products were identified by IR,1H NMR,MS,elemental analysis and X-ray crystal analysis.The reaction mechanism was also proposed. 展开更多
关键词 solid state REACTION nitrogenous COMPOUND INDOLE MICHAEL ADDITION REACTION
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Solid state reactions of nitrogenous heterocyclic compounds(Ⅰ)——Solid state reactions of 3-methyl-l-phenyl-5-pyrazolone with carbonyl compounds 被引量:1
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作者 李晓陆 杜大明 +1 位作者 王永梅 孟继本 《Science China Chemistry》 SCIE EI CAS 1997年第2期205-214,共10页
<正> The solid state reaction of 3-methyl-1-phenyl-5-pyrazolone (MPP) with aromatic aldehydes and ke-tones benzil derivatives and imides,and the solid state Michael addition reaction of MPP with 4-arylidene-3-me... <正> The solid state reaction of 3-methyl-1-phenyl-5-pyrazolone (MPP) with aromatic aldehydes and ke-tones benzil derivatives and imides,and the solid state Michael addition reaction of MPP with 4-arylidene-3-methyl-1-phenyl-5-pyrnzolone 2 were investigated.Some new solid state reactions between the reactants were found,from which a series of new compounds were obtained The structures of the products were identified by IR,1H NMR,MS,elemental analyses and also by X-ray crystal analysis,and the reaction mechanism of MPP with aromatic aldehydes and ketones was proposed 展开更多
关键词 solid state REACTION nitrogenous HETEROCYCLIC compounds 3-methyl-l-phenyl-5-pyrazoIone Michael REACTION
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Electrocatalytic synthesis of C-N coupling compounds from CO_(2) and nitrogenous species 被引量:1
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作者 Zheng Zhang Danyang Li +12 位作者 Yunchuan Tu Jiao Deng Huiting Bi Yongchao Yao Yan Wang Tingshuai Li Yongsong Luo Shengjun Sun Dongdong Zheng Sónia A.C.Carabineiro Zhou Chen Junjiang Zhu Xuping Sun 《SusMat》 SCIE EI 2024年第2期51-74,共24页
The electrocatalytic synthesis of C-N coupling compounds from CO_(2) and nitrogenous species not only offers an effective avenue to achieve carbon neutral-ity and reduce environmental pollution,but also establishes a ... The electrocatalytic synthesis of C-N coupling compounds from CO_(2) and nitrogenous species not only offers an effective avenue to achieve carbon neutral-ity and reduce environmental pollution,but also establishes a route to synthesize valuable chemicals,such as urea,amide,and amine.This innovative approach expands the application range and product categories beyond simple carbona-ceous species in electrocatalytic CO_(2) reduction,which is becoming a rapidly advancing field.This review summarizes the research progress in electrocatalytic urea synthesis,using N_(2),NO_(2)^(-),and NO_(3)^(-)as nitrogenous species,and explores emerging trends in the electrosynthesis of amide and amine from CO_(2) and nitro-gen species.Additionally,the future opportunities in this field are highlighted,including electrosynthesis of amino acids and other compounds containing C-N bonds,anodic C-N coupling reactions beyond water oxidation,and the catalytic mechanism of corresponding reactions.This critical review also captures the insights aimed at accelerating the development of electrochemical C-N coupling reactions,confirming the superiority of this electrochemical method over the traditional techniques. 展开更多
关键词 C-N coupling CO_(2) reduction ELECTROCATALYSIS nitrogenous species reaction mechanism
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Electrocatalytic upcycling of nitrogenous wastes into green ammonia:advances and perspectives on materials innovation 被引量:2
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作者 Yuanting Liu Kui Liu +2 位作者 Pengfei Wang Zhaoyu Jin Panpan Li 《Carbon Neutrality》 2023年第1期295-315,共21页
Ammonia serves as an irreplaceable raw material for nitrogen fertilizers,which is essential for global food production.In addition,it has been recently endowed with a new function as a carrier of renewable energy,demo... Ammonia serves as an irreplaceable raw material for nitrogen fertilizers,which is essential for global food production.In addition,it has been recently endowed with a new function as a carrier of renewable energy,demonstrating significant research prospects.However,the highly developed ammonia industry results in abundant nitrogenous wastes in nature,thus causing severe nitrogen pollution and disrupting the global nitrogen cycle.The environmentally friendly electrocatalytic technologies for upcycling nitrogenous wastes to green ammonia represent a highly valuable transformation strategy.In this review,we present three effective pathways for the electrocatalytic reduction of nitrogenous wastes to green ammonia,including nitrate reduction reaction(NO_(3)RR),nitrite reduction reaction(NO_(2)RR),and nitric oxide reduction reaction(NORR).Furthermore,achievements and challenges associated with electrocatalysts for green ammonia synthesis are discussed in terms of noble metal-based electrocatalysts,non-noble metal-based electrocatalysts,and metal-free electrocatalysts.Moreover,this review provides a systematic perspective on reaction mechanisms,catalyst design,and future developments,offering new insights and prospects for the value-upgrading cycle of nitrogenous substances.By exploring the potential of green ammonia synthesis,we aim to contribute to the development of sustainable and environmentally friendly ammonia production. 展开更多
关键词 ELECTROCATALYSIS Ammonia synthesis Nitrogen cycle nitrogenous wastes
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Preparation of a novel lactose-lignin hydrogel catalyst with self-reduction capacity for nitrogenous wastewater treatment
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作者 Fan Zhang Yanzhu Guo +4 位作者 Xianhong Wu Ce Gao Qingda An Zhongjian Tian Runcang Sun 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2024年第9期25-36,共12页
A novel carboxylated lactose/sodium lignosulfonate/polyacrylic acid hydrogel composites with self-reduction capacity was successfully synthesized by self-assembly method.The hydrogel with well-developed porous structu... A novel carboxylated lactose/sodium lignosulfonate/polyacrylic acid hydrogel composites with self-reduction capacity was successfully synthesized by self-assembly method.The hydrogel with well-developed porous structure provided abundant anchoring points and reduction capacity for transforming Ag^(+)into silver nanoparticles.Silver nanoparticles dispersed among the network of hydrogel and the composites exhibited catalytic capacity.The catalytic performance was evaluated via degradation of p-nitrophenol,rhodamine B,methyl orange and methylene blue,which were catalyzed with corresponding reaction rate constants of 0.04338,0.07499,0.04891,and 0.00628 s^(–1),respectively.In addition,the catalyst exhibited stable performance under fixed-bed condition and the corresponding conversion rate still maintained more than 80%after 540 min.Moreover,the catalytic performance still maintained effective in tap water and simulated seawater.The catalytic efficiency still remained 99.7%with no significant decrease after 8 cycles. 展开更多
关键词 carboxylated lactose Ag NPs self-reduction nitrogenous wastewater
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A Sensitive Method for theδ^(15)N Measurement of Nanomolar Chl-a in Marine Environment
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作者 XIN Yu YAN Maojun +1 位作者 YAN Zhenwei WANG Jiping 《Journal of Ocean University of China》 2026年第1期197-206,共10页
Chlorophyll-a is the most abundant chlorophyll pigment produced by marine phytoplankton,and it bears the isotope signature of the nitrate source assimilated in the N-atoms that are embedded in its porphyrin ring.The c... Chlorophyll-a is the most abundant chlorophyll pigment produced by marine phytoplankton,and it bears the isotope signature of the nitrate source assimilated in the N-atoms that are embedded in its porphyrin ring.The chloropigment and its degradation product,i.e.,pheophytin-a,could be well preserved in marine sediment,usually at nanomolar level.A sensitive and accurate measurement of theδ15N of chloropigment is capable of providing rich information to greatly enhance our understanding of past nitrogen cycling,which therefore is urgently needed.Hereby,we present a successful method based on two-step HPLC separation followed by'denitrifier method'.The N-content in acetone and potassium persulfate(K_(2)S_(2)O_(8))are very critical to the precision and accuracy of the measurements,because they constitute the majority of the N contamination to the Chl-a samples.In this method,the recrystallized K_(2)S_(2)O_(8)that is used as oxidization reagent was discovered to have aδ15N background of-15‰,consolidated by repeated examinations over a period of two months.This 15N background of K_(2)S_(2)O_(8)would cause-1‰–-2‰deviation on theδ^(15)N of sample that contains nanomolar level N,and highlight the need to examine theδ^(15)N of recrystallized K_(2)S_(2)O_(8)when it is used to oxidize samples of organic nitrogen.The overall measurement ofδ^(15)N pigment is reliable and has an average analytical precision better than±0.5‰(1σ).This study establish a sensitive method for accurate measurement of theδ^(15)N of nano-molar level chlorophyll pigment,and with no doubts will advance its wide application in marine nitrogen cycling studying. 展开更多
关键词 nitrogen isotope chlorophyll pigment nitrogen cycling PERSULFATE marine sediment
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Unlocking the potential of DULL NITROGEN RESPONSE 1 for climate-smart crop breeding under elevated CO_(2)
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作者 Muhammad Imran Ming Xu 《Journal of Integrative Plant Biology》 2026年第1期9-12,共4页
Increasing atmospheric CO_(2)concentrations from~280 ppm in the pre-industrial era to over 420 ppm today, and projected to exceed 550 ppm by 2050(IPCC, 2023), are transforming the biochemical context of plant metaboli... Increasing atmospheric CO_(2)concentrations from~280 ppm in the pre-industrial era to over 420 ppm today, and projected to exceed 550 ppm by 2050(IPCC, 2023), are transforming the biochemical context of plant metabolism,causing restructuring of carbon and nitrogen balance in crops. Though elevated CO_(2)(eCO_(2)) increases photosynthetic efficacy and biomass accumulation in many C3crops, it also disrupts carbon-nitrogen balance, leading to nitrogen dilution in leaves and grains, eventually compromising food quality(Myers et al., 2014;Rezaei et al., 2023). Rice is a staple food that feeds nearly half of the world's population;it requires sustained yield gains, considering an estimated 35%-56%increase in demand by 2050, as the global population approaches 10 billion(Van Dijk et al., 2021), while reducing dependency on nitrogen fertilizers, whose production and overuse contribute significantly to greenhouse gas emission(Qian et al., 2023). Yet, most breeding programs remain regulated to present-day atmospheric conditions, overlooking the physiological and molecular adaptations required for future CO_(2)climates. 展开更多
关键词 carbon nitrogen balance food q rice nitrogen response elevated CO food quality photosynthetic efficacy climate smart crop breeding
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Effects of Nitrogen Rate and Planting Density on the Growth and Quality of Tobacco Cultivar Chuxue 80
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作者 Xiao WANG Jiuchang SHI +4 位作者 Guangpu ZHANG Changhe CHENG Guanghua HUANG Huan HUANG Baoming QIAO 《Asian Agricultural Research》 2026年第1期36-38,45,共4页
[Objectives]To investigate the effects of different planting densities and nitrogen application rates on the yield and quality of the tobacco cultivar Chuxue 80.[Methods]A field experiment was conducted in Hubei Provi... [Objectives]To investigate the effects of different planting densities and nitrogen application rates on the yield and quality of the tobacco cultivar Chuxue 80.[Methods]A field experiment was conducted in Hubei Province,evaluating various combinations of planting density and nitrogen rate for Chuxue 80.[Results]At the maturity stage,the TN1 treatment(5 kg N per 667 m^(2) with a density of 1900 plants per 667 m^(2))demonstrated the most favorable agronomic performance.The TN9 treatment(11 kg N per 667 m^(2) with a density of 1110 plants per 667 m^(2))achieved the highest wrapper tobacco yield and output value.Meanwhile,the TN5 treatment(8 kg N per 667 m^(2) with a density of 1515 plants per 667 m^(2))resulted in the best smoking quality.[Conclusions]The TN9 treatment,with a planting density of 1110 plants per 667 m^(2) and a nitrogen application rate of 11 kg per 667 m^(2),is recommended as the optimal cultivation practice for Chuxue 80 in Hubei Province. 展开更多
关键词 TOBACCO Nitrogen application rate PLANTING density AGRONOMIC traits SMOKING QUALITY
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