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粉煤灰基沸石吸附废液中氨氮化物与铜离子的试验研究
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作者 鲍慧敏 《矿冶工程》 CAS 北大核心 2024年第4期253-258,共6页
开展了粉煤灰基沸石吸附电镀废液中氮氧化物和铜离子的试验研究。结果表明:粉煤灰基沸石吸附铜离子的适宜条件为:pH值8,溶液中铜离子初始质量浓度200 mg/L,吸附时间0.45 h,温度200℃;粉煤灰基沸石吸附氨氮化物的适宜条件为:粉煤灰基沸... 开展了粉煤灰基沸石吸附电镀废液中氮氧化物和铜离子的试验研究。结果表明:粉煤灰基沸石吸附铜离子的适宜条件为:pH值8,溶液中铜离子初始质量浓度200 mg/L,吸附时间0.45 h,温度200℃;粉煤灰基沸石吸附氨氮化物的适宜条件为:粉煤灰基沸石投入量8 g/L,pH值8,吸附时间0.60 h,溶液中氨氮化物初始质量浓度150 mg/L;粉煤灰基沸石吸附铜离子的吸附过程为物理吸附过程,粉煤灰基沸石对氨氮化物的吸附是离子交换和物理吸附共同作用的结果。 展开更多
关键词 粉煤灰 沸石 电镀废液 氨氮化物 铜离子 吸附剂 物理吸附
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固定化硝化菌去除废水中氨氮工艺的研究 被引量:36
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作者 赵兴利 兰淑澄 《环境科学》 EI CAS CSCD 北大核心 1999年第1期39-42,共4页
采用聚乙烯醇(PVA)-硼酸包埋固定化法,选用PVA为包埋载体,粉末活性炭作为无机载体,包埋固定A/O生物脱氮系统中的再经驯化过的硝化污泥,制成固定化硝化菌颗粒.以流化床作为生物反应器,采用SBR运行方式对人工配制含... 采用聚乙烯醇(PVA)-硼酸包埋固定化法,选用PVA为包埋载体,粉末活性炭作为无机载体,包埋固定A/O生物脱氮系统中的再经驯化过的硝化污泥,制成固定化硝化菌颗粒.以流化床作为生物反应器,采用SBR运行方式对人工配制含氮废水进行处理试验.结果表明:固定化硝化菌寿命长达7个月以上;固定化硝化菌的呼吸活性由开始时的10.3mg/(L·h),最终达420mg/(L·h)左右;NH4-N去除负荷为240mg/(L·h);当颗粒填充率为4%,进水NH4-N浓度为35mg/L和65mg/L,反应时间分别为5h和9h时,NH4-N去除率皆可达99%以上;当进水COD浓度为230mg/L左右,NH4-N浓度为35mg/L左右,反应时间为4h,COD去除率在86%左右,NH4-N去除率维持在90%左右.用扫描电子显微镜对固定化硝化菌菌群的生长及分布情况进行了观察. 展开更多
关键词 固定化 硝化菌 废水处理 氨氮化物 微生物固定化
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潇河水环境质量评价及其保护对策 被引量:1
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作者 贾风英 李文红 《山西水利科技》 1994年第4期78-82,共5页
潇河是晋中地区的第一大河,是汾河的主要支流之一,上游有白马河、松塔河,全长137km。工业“三废”的排入,使部分河段水质污染,直接影响榆次市工业和生活供水。经过累计7年对潇河水质跟综监测,取样30余个,并应用超标倍数... 潇河是晋中地区的第一大河,是汾河的主要支流之一,上游有白马河、松塔河,全长137km。工业“三废”的排入,使部分河段水质污染,直接影响榆次市工业和生活供水。经过累计7年对潇河水质跟综监测,取样30余个,并应用超标倍数法和灰色聚类法,进行单项和综合评价,其结果是:潇河的主要污染物有:氨氮、氰、酚、铁、亚硝酸盐氮,其中氨氮超标最严重,支流白马河流经寿阳县城,受工矿企业,生活污水影响,河水水质污染严重,如芦家庄断面,1986年氨氮超标41.5倍,1992年增到1330倍;而松塔河远离城镇,水质良好,随着工业的发展,潇河水质仍在不断继续恶化,因此,需加强沿河工业区、生活区排污监测、管理,首先白马河作为重点治理河道,要认真广泛地贯彻“环保”法规,依法管理,控制污染的扩大。 展开更多
关键词 水污染 河流污染 工业废水 生活污水 水质评价 污染防治 氨氮化物 氰化物 有机化合物 有毒物质 潇河
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Effect of Potassium and C/N Ratios on Conversion of NH_4^+ in Soils 被引量:6
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作者 TANG Yan WANG Xiao-Zhi ZHAO Hai-Tao FENG Ke 《Pedosphere》 SCIE CAS CSCD 2008年第4期539-544,共6页
Two soils, one consisting of 1:1 clay minerals at pH 4.5 and the other containing 2:1 clay minerals at pH 7.0, were used to estimate the conversion of added NH+4 under different C/N ratios (glucose as the C source) an... Two soils, one consisting of 1:1 clay minerals at pH 4.5 and the other containing 2:1 clay minerals at pH 7.0, were used to estimate the conversion of added NH+4 under different C/N ratios (glucose as the C source) and the addition of potassium. Under lower C/N ratios (0:1 and 5:1), a large part of the added NH4+ in the acid soil was held in the forms of either exchangeable or water soluble NH4+ for a relatively long time and under higher C/N ratio (50:1), a large amount of the added NH4+ was directly immobilized by microorganisms. In the second soil containing appreciable 2:1 type clay minerals a large part of the added NH+4 at first quickly entered the interlayer of the minerals under both lower and higher C/N ratios. In second condition, however, owing to microbial assimilation stimulated by glucose the newly fixed NH4+c ould be completely released in further incubation because of a large concentration gradient between external NH4+ and fixed NH4+ in the mineral interlayer caused by heterotrophic microorganisms, which imply the fixed NH4+ to be available to plants. The results also showed that if a large amount of K+ with carbon source together was added to soil, the higher K+ concentration of soil solution could impede the release of fixed NH4+ , even if there was a lot of carbon source. 展开更多
关键词 clay minerals fixed NH4^+ N mineralization organic C POTASSIUM
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Supported Cobalt Molybdenum Bimetallic Nitrides for Ammonia Decomposition 被引量:6
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作者 项益智 李小年 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第5期696-700,共5页
Co and Mo bimetallic nitrides supported on Mg(Al)O, MgO and γ-Al2O3 were prepared in temperatureprogrammed reactions with NH3. The surface morphology, chemical composition and catalytic activity for NH3 decompositi... Co and Mo bimetallic nitrides supported on Mg(Al)O, MgO and γ-Al2O3 were prepared in temperatureprogrammed reactions with NH3. The surface morphology, chemical composition and catalytic activity for NH3 decomposition on the supported Co and Mo bimetallic nitrides were studied by X-ray diffractometer (XRD), NH3 temperature-programmed desorption and mass spectrometer (NH3-TPD-MS), temperature-programmed desorption and mass spectrometer (TPD-MS), H2 temperature-programmed surface reaction (H2-TPSR) and activity test. The phases of Co3Mo3N and MoN could be formed on Mg(Al)O, MgO and Al2O3 during the nitridation, and they might be more uniformly dispersed on Mg(Al)O and MgO than on γ-Al2O3. Transition metallic nitrides are generally considered as potential catalysts for hydrogen-involving reactions due to the entrance of hydrogen atoms into subsurface and the lattice of metallic nitrides. The diffusion of nitrogen in the bulk and the structure transformation of Co and Mo nitride compounds occur during NH3-TPD, but the supported Co and Mo bimetallic nitrides are not easily reduced at H2 atmosphere. Co3Mo3N/Mg(Al)O catalyst exhibits the highest activity, while Co3Mo3N/Al2O3 exhibits the lowest activity for NH3 decomposition. Furthermore, the catalytic activity of Co and Mo bimetallic nitrides is not only much higher than that of supported single metallic nitride, but also highly dependent upon the surface acidity and BET surface area of support. 展开更多
关键词 Co and Mo bimetallic nitrides surface morphology SUPPORT ammonia decomposition
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Effects of endogenous nitric oxide induced by 5-fluorouracil and L-Arg on liver carcinoma in nude mice 被引量:6
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作者 Xiao-Yan Yin Jun-Mei Jiang +1 位作者 Ji-Yong Liu Ju-Ren Zhu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第46期6249-6253,共5页
AIM: To study the effects of endogeous nitric oxide induced by 5-fluorouracil (5-FU) and L-arginine (L-Arg) on the human liver carcinoma model in nude mice. METHODS: The human liver carcinoma model in nude mice ... AIM: To study the effects of endogeous nitric oxide induced by 5-fluorouracil (5-FU) and L-arginine (L-Arg) on the human liver carcinoma model in nude mice. METHODS: The human liver carcinoma model in nude mice was established with BEL-7402 cells and normal saline (NS), 5-FU and 5-FU + L-Arg injected intraperitoneally. The tumor size was measured. The necrotic degree and range were observed under microscope. The apoptosis of cancer cell was detected by turmina deoxynucleotidyl transferanse mediated dUTP nick end labeling (TUNEL) method. Immunohistochemical method was performed to determine the expression of iNOS, P16, BAX. The chemical colorimetry was used to test the activity and nitrate reductase method was adopted to test the concentration of nitric oxide (NO) in the tumor tissue. The BI2000 pathological image analyzer was used to analyze the result of immunohistochemistry. RESULTS: 5-FU combined with L-Arg could inhibit the tumor growth apparently. In NS, 5-FU and 5-FU+L- Arg groups, the changes of tumor volumes were 257.978 ± 59.0, 172.232 ± 66.0 and 91.523 ± 26.7 mm3, respectively (P 〈 0.05 5-FU vs 5-FU ± L-Arg group;P 〈 0.05 NS ys 5-FU ± L-Arg group; P 〈 0.05, NS ys 5-FU group). The necrotic range and apoptosis index were significantly increased after the drug injection. The necrotic range was biggest in 5-FU + L-Arg group (X^2= 15.963, P 〈 0.05). The apoptosis indexes were as follows: NS, 17.4% ± 6.19%; 5-FU, 31.3% ± 12.3%; and 5-FU ± L-Arg, 46% ± 15.24% (P 〈 0.05, 5-FU ys 5-FU ± L-Arg; P 〈 0.05, NS ys 5-FU ± L-Arg; P 〈 0.05, NS ys 5-FU). The expression and activity of iNOS were increased in the tumor tissue. The concentration of NO was also increased. F of opticaldensity of iNOS, iNOS activity and NO concentration are 31.693, 21.949, and 33.909, respectively, P 〈 0.05. The concentration of NO was related to the expression of PI6 and BAX. The correlation coefficient was 0.764 and 0.554. CONCLUSION: 5-FU combined with L-Arg can inhibit the growth of tumor in nude mice. The effect may be related to inducing the synthesis and increasing the activity of iNOS. The production of NO is increased, and it can enhance the expression of apoptosis-related gene and antioncogene. 展开更多
关键词 5-FLUOROURACIL L-ARGININE Animal model Nitric oxide synthase Nitric oxide
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Synthesis and Structure of bis(μ-2-aminopyridine N-oxide)-bis[dichlorocopper(II)] 被引量:1
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作者 牛德绅 路再生 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2001年第4期270-273,共4页
The complex [Cu2(apo)4Cl4]·2H2O (apo=2-aminopyridine N-oxide) was obtained. A single- crystal X-ray study shows that the complex is a binuclear compound (Cu2C20H28Cl4N8O6). The coordination geometry about e... The complex [Cu2(apo)4Cl4]·2H2O (apo=2-aminopyridine N-oxide) was obtained. A single- crystal X-ray study shows that the complex is a binuclear compound (Cu2C20H28Cl4N8O6). The coordination geometry about each copper atom is best described as a distorted square pyramid. The compound [Cu2(apo)4Cl4]·2H2O belongs to the triclinic system with space group P, lattice constants: a = 7.8550(7), b = 8.5378(7), c = 12.082(1) ?, α = 72.807(1), β = 77.641(1), γ = 70.800(1)(, V =724.85(11) ?3, Z=1, Mr =745.38, Dc=1.708 g/cm3, μ =1.886mm-1, F(000) =378, R=0.0359, wR2=0.0884 for 2220 reflections with I >2σ(I). The distances between Cu(II) and O atoms are in the range from 1.934(2) to 2.042(2)?. The distance between two copper atoms Cu-Cu(A) is 3.2978(8) ?. The distances of Cu-Cl(1) and Cu-Cl(2) are 2.2322(9), 2.5095(10) ?, respectively. There is no evident hydrogen bond between N and Cl. 展开更多
关键词 crystal structure copper(II) 2-aminopyridine N-oxide binuclear complex
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Some New Derivatives of 3H-Benzo (b) Furo Benzotriazole 被引量:1
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作者 Mamuka Maisuradze Grigol Ugulava Nona Bolkvadze Giorgi Phalavandishvili Nana Gaxokidze MananaMatnadze 《Journal of Chemistry and Chemical Engineering》 2013年第7期621-625,共5页
On the base of benzo [b] furo benzotriazoles several derivatives with expected biological activity were synthesized by alkylation and Mannich reactions. In the alkylation of ethyl iodide benzo [b] furo benzotriazoles ... On the base of benzo [b] furo benzotriazoles several derivatives with expected biological activity were synthesized by alkylation and Mannich reactions. In the alkylation of ethyl iodide benzo [b] furo benzotriazoles received 1-ethyl-benzo [b] furo [3,2-g] benzotriazole and 3-ethyl-benzo [b] furo [2,3-f] benzotriazole. Aminometilirization Mannich reaction conditions with "the application as amino compound diethylamine, morpholine and piperazine of benzo [b] furo benzotriazoles were received (N, N-diethylaminomethyl), CN-morpholinometil) and (N-piperazinometil)-derivatives. 展开更多
关键词 3H-benzo [b] furo [2 3-e] benzotriazole 3H-benzo [b] furo [2 3-q benzotriazole reaction of alkylation reaction ofmannich.
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Influence of preparation methods on the physicochemical properties and catalytic performance of MnO_x-CeO_2 catalysts for NH_3-SCR at low temperature 被引量:47
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作者 Xiaojiang Yao Kaili Ma +4 位作者 Weixin Zou Shenggui He Jibin An Fumo Yang Lin Dong 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第1期146-159,共14页
This work examines the influence of preparation methods on the physicochemical properties and catalytic performance of MnOx‐CeO2 catalysts for selective catalytic reduction of NO by NH3 (NH3‐SCR) at low temperature.... This work examines the influence of preparation methods on the physicochemical properties and catalytic performance of MnOx‐CeO2 catalysts for selective catalytic reduction of NO by NH3 (NH3‐SCR) at low temperature. Five different methods, namely, mechanical mixing, impregnation,hydrothermal treatment, co‐precipitation, and a sol‐gel technique, were used to synthesizeMnOx‐CeO2 catalysts. The catalysts were characterized in detail, and an NH3‐SCR model reaction waschosen to evaluate the catalytic performance. The results showed that the preparation methodsaffected the catalytic performance in the order: hydrothermal treatment > sol‐gel > co‐precipitation> impregnation > mechanical mixing. This order correlated with the surface Ce3+ and Mn4+ content,oxygen vacancies and surface adsorbed oxygen species concentration, and the amount of acidic sitesand acidic strength. This trend is related to redox interactions between MnOx and CeO2. The catalystformed by a hydrothermal treatment exhibited excellent physicochemical properties, optimal catalyticperformance, and good H2O resistance in NH3‐SCR reaction. This was attributed to incorporationof Mnn+ into the CeO2 lattice to form a uniform ceria‐based solid solution (containing Mn‐O‐Cestructures). Strengthening of the electronic interactions between MnOx and CeO2, driven by thehigh‐temperature and high‐pressure conditions during the hydrothermal treatment also improved the catalyst characteristics. Thus, the hydrothermal treatment method is an efficient and environment‐friendly route to synthesizing low‐temperature denitrification (deNOx) catalysts. 展开更多
关键词 MnOx‐CeO2 catalyst Preparation method Nitrogen oxides Low‐temperature NH3‐SCR Electron interaction Surface acidity
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SYNTHESIS OF A NOVEL CHELATING RESIN WITH HETEROCYCLIC RING OF S AND N 被引量:1
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作者 QU Rongjun SUNChangmei +2 位作者 JI Chunnuan WANG Chunhua CHENG Guoxiang 《Chinese Journal of Reactive Polymers》 2003年第1期83-86,共4页
By the reaction of poly(bromoacetyl styrene) (EBPS) with thiaurea (TU), a kind of novel chelating resin with heterocyaclic ring of sulfur and nitrogen, poly[4-(2-amino)thiazoleyl-4- vinylbenzene], was synthesized. Its... By the reaction of poly(bromoacetyl styrene) (EBPS) with thiaurea (TU), a kind of novel chelating resin with heterocyaclic ring of sulfur and nitrogen, poly[4-(2-amino)thiazoleyl-4- vinylbenzene], was synthesized. Its structure was characterized by FTIR and elemental analysis. The factors which have influence on the reaction such as reaction time, solvents, and molar ratio of reactants were investigated. 展开更多
关键词 chelating resin SYNTHESIS poly[4-(2-amino)thiazoleyl-4-vinylbenzene]
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Preparation, Characterization and Biological Activity Studies of New Azo Compounds
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作者 Mouayad. N. Mohammed 《Journal of Chemistry and Chemical Engineering》 2012年第10期885-888,共4页
A new series of azo were derived from 2,5-di(p-amino phenyl)-3,6-diphenyl pyrazine in the presence of benzoic acid, salicylic acid, p-amino salicylic acid, p-methoxy phenol and pmethyl phenol. The structures of the ... A new series of azo were derived from 2,5-di(p-amino phenyl)-3,6-diphenyl pyrazine in the presence of benzoic acid, salicylic acid, p-amino salicylic acid, p-methoxy phenol and pmethyl phenol. The structures of the synthesized compounds were determined on the basis of their FTIR, UV (ultraviolet), elemental analysis and H-NMR (H-nuclear magnetic resonance) spectral date. The purity of synthesized compounds was checked by performing TLC (thin layer chromatography). The antibacterial activity was evaluated in DMSO (dimethyl sulfoxide). 展开更多
关键词 PYRAZINE benzoic acid salicylic acid p-amino salicylic acid p-methoxy phenol p-methyl phenol.
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Effects of dietary fresh fermented soybean meal on growth performance, ammonia and particulate matter emissions, and nitrogen excretion in nursery piglets 被引量:16
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作者 Sai-sai CHENG Yuan LI +3 位作者 Shi-jie GENG Luan-sha HU Xiong-feng FU Xin-yan HAN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2017年第12期1083-1092,共10页
This study was conducted to investigate the effects of fresh fermented soybean meal(FSM) on the growth performance of nursery piglets, nitrogen excretion in feces, and the concentrations of ammonia(NH3) and partic... This study was conducted to investigate the effects of fresh fermented soybean meal(FSM) on the growth performance of nursery piglets, nitrogen excretion in feces, and the concentrations of ammonia(NH3) and particulate matter(PM) in the piggery. A total of 472 nursery piglets(Landrace×Yorkshire,(16.3±0.36) kg body weight) were randomly allocated into two treatments with 236 pigs in each treatment. The pigs were fed the basal diet without fresh FSM(control) or diet containing 10%(100 g/kg) fresh FSM(FSM group), and the crude protein content of the two groups was consistent. The feeding trial lasted for 28 d. The results showed that the pigs fed fresh FSM had increased(P〈0.05) average daily gain(ADG) compared with the control. There was no significant difference(P〈0.05) in feed to gain ratio(F:G) between the two groups. During the whole experiment, the concentration of NH3 in the piggery decreased(P〈0.05) by 19.0%, and the concentrations of PM(PM(10) and PM(2.5)) in the piggery decreased(P〈0.05) by 19.9% and 11.6%, respectively, in the FSM group, compared with the control. The ammonia nitrogen and nitrite content in feces increased(P〈0.05) by 32.9% and 28.4%, respectively, in the FSM group. The fecal p H declined(P〈0.05) significantly in the FSM group compared with the control. At the end of experiment, total protein(TP) concentration was increased(P〈0.05) significantly and blood urea nitrogen(BUN) concentration was decreased(P〈0.05) for pigs fed the diet with fresh FSM. The results indicated that dietary fresh FSM not only improved the growth performance of nursery piglets, but also reduced the NH3 concentration in the piggery due to nitrogen conversion, and decreased the concentrations of PM(10) and PM(2.5) in the piggery. 展开更多
关键词 Fresh fermented soybean meal AMMONIA Particulate matter Nitrogen conversion Nursery piglet
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Effects of Silver Nanoparticles on Soil Ammonia-Oxidizing Microorganisms Under Temperatures of 25 and 5℃
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作者 HUANG Juan CAO Chong +1 位作者 LI Runqing GUAN Wenzhu 《Pedosphere》 SCIE CAS CSCD 2018年第4期607-616,共10页
The excellent bactericidal performance of silver nanoparticles (Ag NPs) has led to their wide applications, resulting in increasing concerns about their potential environmental impacts. This study evaluated the infl... The excellent bactericidal performance of silver nanoparticles (Ag NPs) has led to their wide applications, resulting in increasing concerns about their potential environmental impacts. This study evaluated the influences of different concentrations of Ag NPs (0, 1, 10, and 100 μg g^-1 dry soil) on the ammonia-oxidizing microorganisms in soil at cultivation temperatures of 25 and 5 ℃ for 37 d. The results showed that 1μg g^-1 dry soil of Ag NPs had no acute effects on the ammonia-oxidizing microorganisms. However, 10 and 100μg g^-1 dry soil of Ag NPs levels were found to significantly inhibit the activities of soil nitrification, with a decrease of 69.89% and 94.55%, respectively, at 25 ℃ and 61.65% and 83.79%, respectively, at 5℃ compared to the control (0 μg g^-1 dry soil of Ag NPs). These levels of Ag NPs also obviously decreased soil urease activity from about 380.47 ± 0.07 (at 5℃) and 529.76 ± 13.44 (at 25℃) mg N g^-1 dry soil d^-1 to 61.70 ± 2.97 and 68.29 ± 8.22 mg N g^-1 dry soil d^-1, respectively, after 37 d of cultivation. Quantitative polymerase chain reaction showed the abundance of ammonia-oxidizing archaea and bacteria. For the same exposure time, the effects of Ag NPs on the activities of ammonia-oxidizing microorganisms and urease decreased with decreasing temperature. The threshold concentration of Ag NPs that induced negative effects on ammonia-oxidizing microorganisms was higher at 5 -C than at 25 -C. Therefore, the temperature has a major impact on the toxicity of Ag NPs to ammonia-oxidizing microorganisms and on the urease activity, with toxicity being reduced with decreasing temperature. 展开更多
关键词 ARCHAEA bacteria biological toxicity nitrification activity polymerase chain reaction urease activity
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Synthesis of aziridines by visible-light induced decarboxylative cyclization of N-aryl glycines and diazo compounds
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作者 Yong Liu Xichang Dong +1 位作者 Guojun Deng Lei Zhou 《Science China Chemistry》 SCIE EI CAS CSCD 2016年第2期199-202,共4页
A visible-light induced decarboxylative aza-Darzens reaction between N-aryl glycines and diazo compounds was developed, which affords various mono-substituted aziridines in good yields.
关键词 visible light diazo compound DECARBOXYLATION aza-Darzens reaction
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