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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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Yield and Quality of Forage Oat (<i>Avena sativa</i>L.) Cultivars as Affected by Seed Inoculation with Nitrogenous Strains 被引量:3
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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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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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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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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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Carbonaceous and nitrogenous disinfection by-product formation in the surface and ground water treatment plants using Yellow River as water source 被引量:7
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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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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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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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Turnover and loss of nitrogenous compounds during composting of food wastes 被引量:8
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作者 Yanmei YANG Xiangfeng ZHANG +2 位作者 Zhifeng YANG Beidou XI Hongliang LIU 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2008年第2期251-256,共6页
Few people have so far explored into the research of the dynamics of various nitrogenous compounds(including water-soluble nitrogen)in composting of food wastes.This study aimed to investigate the solid-phase nitrogen... Few people have so far explored into the research of the dynamics of various nitrogenous compounds(including water-soluble nitrogen)in composting of food wastes.This study aimed to investigate the solid-phase nitrogen,water-soluble nitrogen,nitrogen loss together with ammonia volatilization in the process of food wastes composting.A laboratory scale static aerobic reactor in the experiment was employed in the composting process of a synthetic food waste,in which sawdust was used as the litter amendment.In the experiment,oxygen was supplied by continuous forced ventilation for 15 days.The results have shown that the concentrations of total nitrogen and organic nitrogen decrease significantly in the composting process,whereasNH_(4)^(+)-N concentration increases together with little fluctuation in NO_(3)^(-)-N.After composting,the total content of the water-soluble nitrogen compounds in the compost greatly increased,the total nitrogen loss amounted to 50% of the initial nitrogen,mainly attributed to ammonia volatilization.56.7% of the total ammonia volatilization occurred in the middle and late composting of the thermophilic stage.This suggested that the control at the middle and late composting of thermophilic stage is the key to nitrogen loss in the food waste compost. 展开更多
关键词 COMPOSTING nitrogen transformation nitrogen loss ammonia volatilization
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Dynamics of nitrogenous compounds and their control in biofloc technology (BFT) systemsA review 被引量:2
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作者 Godwin Abakari Guozhi Luo Emmanuel O.Kombat 《Aquaculture and Fisheries》 2021年第5期441-447,共7页
Controlling toxic nitrogenous substances in biofloc technology(BFT)systems is critical for the success of this novel technology.To effectively control nitrogen accumulation in BFT systems,it is important to first unde... Controlling toxic nitrogenous substances in biofloc technology(BFT)systems is critical for the success of this novel technology.To effectively control nitrogen accumulation in BFT systems,it is important to first understand the dynamics and the removal pathways of this element and its related compounds from aquaculture water.This review focuses on synthesizing the information of nitrogen dynamics in BFT systems to provide researchers and practitioners with a guide to the fate of nitrogen and its control methods.This paper discusses the different types of nitrogenous compounds in BFT water,the transformation processes of ammonia to nitrites and nitrates,the relationship between the two forms of ammonia(NH3 and NH4+)in water and the equilibrium between them.This paper also discusses nitrification as a major nitrogen removal pathway and the factors that influence the nitrification process.Notably,the control of nitrogen in BFT systems by manipulating the carbon to nitrogen ratio(C/N)using external carbohydrates is described in this paper.This paper suggests that further studies should focus on investigating the various factors that influence nitrogen dynamics in BFT systems and the means of controlling contaminants other than nitrogen. 展开更多
关键词 Biofloc technology NITRIFICATION Nitrogen dynamics HETEROTROPHIC Nitrifying bacteria
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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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Increased dependence on nitrogen-fixation of a native legume in competition with an invasive plant 被引量:1
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作者 Meixu Han Haiyang Zhang +12 位作者 Mingchao Liu Jinqi Tang Xiaocheng Guo Weizheng Ren Yong Zhao Qingpei Yang Binglin Guo Qinwen Han Yulong Feng Zhipei Feng Honghui Wu Xitian Yang Deliang Kong 《Plant Diversity》 SCIE CAS CSCD 2024年第4期510-518,共9页
Suppression of roots and/or their symbiotic microorganisms,such as mycorrhizal fungi and rhizobia,is an effective way for alien plants to outcompete native plants.However,little is known about how invasive and native ... Suppression of roots and/or their symbiotic microorganisms,such as mycorrhizal fungi and rhizobia,is an effective way for alien plants to outcompete native plants.However,little is known about how invasive and native plants interact with the quantity and activity of nutrient-acquisition agents.Here a pot experiment was conducted with monoculture and mixed plantings of an invasive plant,Xanthium strumarium,and a common native legume,Glycine max.We measured traits related to root and nodule quantity and activity and mycorrhizal colonization.Compared to the monoculture,fine root quantity(biomass,surface area)and activity(root nitrogen(N)concentration,acid phosphatase activity)of G.max decreased in mixed plantings;nodule quantity(biomass)decreased by 45%,while nodule activity in Nfixing via rhizobium increased by 106%;mycorrhizal colonization was unaffected.Contribution of N fixation to leaf N content in G.max increased in the mixed plantings,and this increase was attributed to a decrease in the rhizosphere soil N of G.max in the mixed plantings.Increased root quantity and activity,along with a higher mycorrhizal association was observed in X.strumarium in the mixed compared to monoculture.Together,the invasive plant did not directly scavenge N from nodule-fixed N,but rather depleted the rhizosphere soil N of the legume,thereby stimulating the activity of N-fixation and increasing the dependence of the native legume on this N source.The quantity-activity framework holds promise for future studies on how native legumes respond to alien plant invasions. 展开更多
关键词 Mycorrhizal strategy Nitrogen depletion Plant invasion Root nutrient acquisition strategy Symbiotic nitrogen fixation
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ZmbZIP27 regulates nitrogen-mediated leaf angle by modulating lignin deposition in maize 被引量:1
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作者 Huan Chen Xiaoping Gong +3 位作者 Yu Guo Jingjuan Yu Wen-Xue Li Qingguo Du 《The Crop Journal》 SCIE CSCD 2024年第5期1404-1413,共10页
In grain crops such as maize(Zea mays),leaf angle(LA)is a key agronomic trait affecting light interception and thus planting density and yield.Nitrogen(N)affects LA in plants,but we lack a good understanding of how N ... In grain crops such as maize(Zea mays),leaf angle(LA)is a key agronomic trait affecting light interception and thus planting density and yield.Nitrogen(N)affects LA in plants,but we lack a good understanding of how N regulates LA.Here,we report that N deficiency enhanced lignin deposition in the ligular region of maize seedlings.In situ hybridization showed that the bZIP transcription factor gene ZmbZIP27 is mainly expressed in the phloem of maize vascular bundles.Under N-sufficient conditions,transgenic maize overexpressing ZmbZIP27 showed significantly smaller LA compared with wild type(WT).By contrast,zmbzip27_(ems)mutant showed larger LA under both N-deficient and N-sufficient conditions compared with WT.Overexpression of ZmbZIP27 enhanced lignin deposition in the ligular region of maize in the field.We further demonstrated that ZmbZIP27 could directly bind the promoters of the microRNA genes ZmMIR528a and ZmMIR528b and negatively regulate the expression levels of ZmmiR528.ZmmiR528 knockdown transgenic maize displayed erect architecture in the field by increasing lignin content in the ligular region of maize.Taken together,these results indicate that ZmbZIP27 regulates N-mediated LA size by regulating the expression of ZmmiR528 and modulating lignin deposition in maize. 展开更多
关键词 MAIZE NITROGEN Leaf angle Ligular region Lignin deposition
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Regulation of 2-acetyl-1-pyrroline and grain quality in early-season indica fragrant rice by nitrogen and silicon fertilization under different plantation methods 被引量:1
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作者 Yongjian Chen Lan Dai +7 位作者 Siren Cheng Yong Ren Huizi Deng Xinyi Wang Yuzhan Li Xiangru Tang Zaiman Wang Zhaowen Mo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期511-535,共25页
Fragrant rice has a high market value,and it is a popular rice type among consumers owing to its pleasant flavor.Plantation methods,nitrogen(N)fertilizers,and silicon(Si)fertilizers can affect the grain yield and frag... Fragrant rice has a high market value,and it is a popular rice type among consumers owing to its pleasant flavor.Plantation methods,nitrogen(N)fertilizers,and silicon(Si)fertilizers can affect the grain yield and fragrance of fragrant rice.However,the core commercial rice production attributes,namely the head rice yield(HRY)and 2-acetyl-1-pyrroline(2-AP)content of fragrant rice,under various nitrogen and silicon(N-Si)fertilization levels and different plantation methods remain unknown.The field experiment in this study was performed in the early seasons of 2018 and 2019 with two popular indica fragrant rice cultivars(Yuxiangyouzhan and Xiangyaxiangzhan).They were grown under six N-Si fertilization treatments(combinations of two levels of Si fertilizer,0 kg Si ha^(−1)(Si0)and 150 kg Si ha^(−1)(Si1),and three levels of N fertilizer,0 kg N ha^(−1)(N0),150 kg N ha^(−1)(N1),and 220 kg N ha^(−1)(N2))and three plantation methods(artificial transplanting(AT),mechanical transplanting(MT),and mechanical direct-seeding(MD)).The results showed that the N-Si fertilization treatments and all the plantation methods significantly affected the HRY and 2-AP content and related parameters of the two different fragrant rice cultivars.Compared with the Si0N0 treatment,the N-Si fertilization treatments resulted in higher HRY and 2-AP contents.The rates of brown rice,milled rice,head rice,and chalky rice of the fragrant rice also improved with the N-Si fertilization treatments.The N-Si fertilization treatments increased the activities of N metabolism enzymes and the accumulation of N and Si in various parts of the fragrant rice,and affected their antioxidant response parameters.The key parameters for the HRY and 2-AP content were assessed by redundancy analysis.Furthermore,the structural equation model revealed that the Si and N accumulation levels indirectly affected the HRY by affecting the N metabolism enzyme activity,N use efficiency,and grain quality of fragrant rice.Moreover,high N and Si accumulation directly promoted the 2-AP content or affected the antioxidant response parameters and indirectly regulated 2-AP synthesis.The interactions of the MT method with the N-Si fertilization treatments varied in the fragrant rice cultivars in terms of the HRY and 2-AP content,whereas the MD method was beneficial to the 2-AP content in both fragrant rice cultivars under the N-Si fertilization treatments. 展开更多
关键词 fragrant rice 2-AP content head rice yield mechanical planting NITROGEN silicon
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Active MoS_(2)-based electrode for green ammonia synthesis 被引量:1
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作者 Xin Liu Lei Yang +2 位作者 Tao Wei Shanping Liu Beibei Xiao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期268-275,共8页
Nitrogen electro-reduction under mild conditions is one promising alternative approach of the energyconsuming Haber-Bosch process for the artificial ammonia synthesis.One critical aspect to unlocking this technology i... Nitrogen electro-reduction under mild conditions is one promising alternative approach of the energyconsuming Haber-Bosch process for the artificial ammonia synthesis.One critical aspect to unlocking this technology is to discover the catalysts with high selectivity and efficiency.In this work,the N_(2)-to-NH_(3)conversion on the functional MoS_(2)is fully investigated by density functional theory calculations since the layered MoS_(2)provides the ideal platform for the elaborating copies of the nitrogenase found in nature,wherein the functionalization is achieved via basal-adsorption,basal-substitution or edge-substitution of transition metal elements.Our results reveal that the edge-functionalization is a feasible strategy for the activity promotion;however,the basal-adsorption and basal-substitution separately suffer from the electrochemical instability and the NRR inefficiency.Specifically,MoS_(2)functionalized via edge W-substitution exhibits an exceptional activity.The energetically favored reaction pathway is through the distal pathway and a limiting potential is less than 0.20 V.Overall,this work escalates the rational design of the high-effective catalysts for nitrogen fixation and provides the explanation why the predicated catalyst have a good performance,paving the guidance for the experiments. 展开更多
关键词 Nitrogen reduction reaction Density functional theory calculations Molybdenum disulfide ELECTROCHEMISTRY CATALYST THERMODYNAMICS
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Microfluidic-oriented synthesis of enriched iridium nanodots/carbon architecture for robust electrocatalytic nitrogen fixation 被引量:1
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作者 Hengyuan Liu Xingjiang Wu +2 位作者 Yuhao Geng Xin Li Jianhong Xu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第3期544-555,共12页
Electrocatalytic nitrogen reduction reaction(NRR)is considered as a promising candidate to achieve ammonia synthesis because of clean electric energy,moderate reaction condition,safe operating process and harmless by-... Electrocatalytic nitrogen reduction reaction(NRR)is considered as a promising candidate to achieve ammonia synthesis because of clean electric energy,moderate reaction condition,safe operating process and harmless by-products.However,the chemical inertness of nitrogen and poor activated capacity on catalyst surface usually produce low ammonia yield and faradic efficiency.Herein,the microfluidic technology is proposed to efficiently fabricate enriched iridium nanodots/carbon architecture.Owing to in-situ co-precipitation reaction and microfluidic manipulation,the iridium nanodots/carbon nanomaterials possess small average size,uniform dispersion,high conductivity and abundant active sites,producing good proton activation and rapid electrons transmission and moderate adsorption/desorption capacity.As a result,the as-prepared iridium nanodots/carbon nanomaterials realize large ammonia yield of 28.73 μg h^(-1) cm^(-2) and faradic efficiency of 9.14%in KOH solution.Moreover,the high ammonia yield of 11.21 μg h^(-1) cm^(-2) and faradic efficiency of 24.30%are also achieved in H_(2)SO_(4) solution.The microfluidic method provides a reference for large-scale fabrication of nano-sized catalyst materials,which may accelerate the progress of electrocatalytic NRR in industrialization field. 展开更多
关键词 Iridium nanodots CARBON Microfluidic technology Efficient synthesis Electrocatalytic nitrogen fixation
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