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1,4--二氮氧喹噁啉甲醛衍生物的合成及其抑菌和除草活性 被引量:5
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作者 王洪波 马敬中 张方钰 《湖北化工》 2003年第2期21-23,共3页
合成了10种1,4 二氮氧 2 喹啉甲醛衍生物。用HNMR和元素分析对这些化合物的结构进行了表征,并对这些化合物抑菌和除草活性进行了研究。试验结果表明:席夫碱类1,4 二氮氧 2 喹啉甲醛衍生物对几种真菌(水稻纹枯病菌、小麦赤霉病菌、... 合成了10种1,4 二氮氧 2 喹啉甲醛衍生物。用HNMR和元素分析对这些化合物的结构进行了表征,并对这些化合物抑菌和除草活性进行了研究。试验结果表明:席夫碱类1,4 二氮氧 2 喹啉甲醛衍生物对几种真菌(水稻纹枯病菌、小麦赤霉病菌、山药炭疽病菌、玉米小斑病菌、稻谷弯孢病菌)的抑菌率平均高于酰腙类化合物的抑菌率。席夫碱和脂肪酰腙化合物对阔叶杂草和稗草的生长有较明显的抑制作用,而芳香酰腙的除草活性较弱。 展开更多
关键词 l 4—二喹噁啉甲醛衍生物 合成 抑菌 除草活性 结构表征 农药
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1,4-氧氮杂萘-2-酮类衍生物的电子轰击质谱分析
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作者 杨小兵 丁松涛 王安邦 《分析化学》 SCIE EI CAS CSCD 北大核心 2006年第10期1445-1447,共3页
用电子轰击质谱(EI-MS)研究了1,4-氧氮杂萘-2-酮系列衍生物,分析并探讨了不同取代基对这类化合物EI-MS谱图的影响,分析得到一些裂解规律。
关键词 电子轰击质谱 1 4-杂萘-2-酮系列衍生物 裂解规律
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侧流除磷ERP-SBR新工艺中生物脱氮及影响因素研究 被引量:2
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作者 吉芳英 肖铁岩 罗固源 《环境污染治理技术与设备》 CSCD 北大核心 2006年第7期20-24,共5页
侧流除磷ERP·SBR新工艺在进水COD=338-527mg/L、TN=40~60mg/L、TP=8~11mg/L的水质条件下,出水COD≤39mg/L、NH3-N≤1.8mg/L、TN≤〈5.8mg/L、TP≤0.29mg/L,且72%的总氮损失发生在好氧曝气阶段。在分析是影响该工艺... 侧流除磷ERP·SBR新工艺在进水COD=338-527mg/L、TN=40~60mg/L、TP=8~11mg/L的水质条件下,出水COD≤39mg/L、NH3-N≤1.8mg/L、TN≤〈5.8mg/L、TP≤0.29mg/L,且72%的总氮损失发生在好氧曝气阶段。在分析是影响该工艺生物脱氮因素时发现:SBR反应器的DO时间分布是影响好氧生物脱氮和缺氧内碳源反硝化的重要因素;侧流除磷工艺特有的高浓度活性污泥、颗粒大且密实的污泥絮体有利于形成好氧生物脱氮过程所需要的微环境;控制较长的污泥龄有利于提高系统的好氧脱氮能力,SRT与好氧脱氮率之间具有良好的线性关系:ηODN(%)=0.89×SRT-5.74。 展开更多
关键词 生物 侧流除磷 生物 污水处理 ERP-SBR
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1,3-氧氮杂环戊烷类化合物在Chiralcel OD上的对映异构体拆分 被引量:2
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作者 蔡小军 张大同 《浙江大学学报(理学版)》 CAS CSCD 北大核心 2010年第1期67-71,共5页
2位取代的5-氯甲基-1,3-氧氮杂环戊烷衍生物具有两个手性中心,有多种生理和生物活性.利用Chiralcel OD手性柱,首次对通过非手性选择性合成的2,3-二苯基-5-氯甲基-1,3-氧氮杂环戊烷和2-(4′-硝基苯)-3-苯基-5-氯甲基-1,3-氧氮杂环戊烷进... 2位取代的5-氯甲基-1,3-氧氮杂环戊烷衍生物具有两个手性中心,有多种生理和生物活性.利用Chiralcel OD手性柱,首次对通过非手性选择性合成的2,3-二苯基-5-氯甲基-1,3-氧氮杂环戊烷和2-(4′-硝基苯)-3-苯基-5-氯甲基-1,3-氧氮杂环戊烷进行手性拆分研究.考察了流动相中极性添加剂以及柱温对拆分的影响.初步探讨了其手性识别的作用机理.发现在正相体系下溶质的4个对映异构体都获得了很好的拆分. 展开更多
关键词 1 3-杂环戊烷衍生物 CHIRALCEL OD 手性固定相(CSP) 对映体分离 高效液相色谱
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2-{2-[3-(取代苯基)-3-氧代-2-1,2,4-三唑-1-基-丙基]-苯基}-2-甲氧亚氨基乙酸甲酯和乙酰甲胺类衍生物的合成与杀菌活性研究 被引量:3
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作者 李国华 杨红 《有机化学》 SCIE CAS CSCD 北大核心 2008年第11期1918-1924,共7页
以2-甲基苯甲酰甲酸甲酯为起始原料,通过与甲氧基胺的盐酸盐、甲胺、N-溴代丁二酰亚胺(NBS)和1H-1,2,4-三氮唑钠反应合成了两个系列共计22个2-{2-[3-(取代苯基)-3-氧代-2-1,2,4-三唑-1-基-丙基]-苯基}-2-甲氧亚氨基乙酸甲酯和乙酰甲胺... 以2-甲基苯甲酰甲酸甲酯为起始原料,通过与甲氧基胺的盐酸盐、甲胺、N-溴代丁二酰亚胺(NBS)和1H-1,2,4-三氮唑钠反应合成了两个系列共计22个2-{2-[3-(取代苯基)-3-氧代-2-1,2,4-三唑-1-基-丙基]-苯基}-2-甲氧亚氨基乙酸甲酯和乙酰甲胺类的衍生物.经IR,1HNMR和MS对目标化合物进行了结构表征.用浓度为10μg?mL-1的目标化合物进行了初步离体杀菌活性试验,结果表明:Ha4,Ha5,Ha7对油菜菌核病有杀菌活性;Ha2,Hb8对小麦纹枯病有杀菌活性;Hb4对蔬菜灰霉病有杀菌活性;Hb4,Hb5对小麦赤霉病和小麦纹枯病均有杀菌活性. 展开更多
关键词 2-甲基-2-苯基乙酸衍生物 1H-1 2 4-三 合成 杀菌活性
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吡啶氮氧化衍生物与酰胺大环化合物络合性能与结构的关系 被引量:1
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作者 陈木娟 韩淑娟 +3 位作者 廖振华 黄丹 李颖 蒋腊生 《有机化学》 SCIE CAS CSCD 北大核心 2015年第11期2358-2365,共8页
介绍了3,5-吡啶二甲酸氮氧衍生物作为客体分子与主体分子酰胺大环的相互作用.通过质谱和核磁共振氢谱等实验技术研究了吡啶氮氧化物和酰胺大环化合物的结构特点对两者络合作用的影响.实验结果表明,3,5-吡啶二甲酰苄胺氮氧化物与酰胺大... 介绍了3,5-吡啶二甲酸氮氧衍生物作为客体分子与主体分子酰胺大环的相互作用.通过质谱和核磁共振氢谱等实验技术研究了吡啶氮氧化物和酰胺大环化合物的结构特点对两者络合作用的影响.实验结果表明,3,5-吡啶二甲酰苄胺氮氧化物与酰胺大环化合物的络合能力最强,3,5-吡啶二甲酰丁胺氮氧化物次之,3,5-吡啶二甲酸苄酯氮氧化物最弱.酰胺大环分子的空腔越大其络合吡啶氮氧化物的能力越弱,酰胺大环上是否含有吡啶环结构对其络合氮氧化物的能力影响较小.并通过核磁实验进一步验证吡啶酰胺氮氧化合物与酰胺大环形成的[2]准轮烷分子在三氟乙酸/三乙胺的作用下能够发生解离/再组装行为. 展开更多
关键词 3 5-吡啶二甲酸生物 酰胺大环分子 主客体化学 准轮烷
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分子生态技术对厌氧脱氮除磷微生物优势菌群的鉴定 被引量:2
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作者 张刚 骆炜诗 贾晓珊 《环境工程学报》 CAS CSCD 北大核心 2013年第3期1181-1188,共8页
应用分子生态克隆技术,直接对A/O反应器所驯化培养的厌氧脱氮除磷微生物样品进行主要功能菌群的分子生态学鉴定。通过克隆文库的序列分析,发现驯化培养后厌氧污泥样品中的优势菌群主要是Azospirillum和Selenomonas两个属。这一结果表明... 应用分子生态克隆技术,直接对A/O反应器所驯化培养的厌氧脱氮除磷微生物样品进行主要功能菌群的分子生态学鉴定。通过克隆文库的序列分析,发现驯化培养后厌氧污泥样品中的优势菌群主要是Azospirillum和Selenomonas两个属。这一结果表明,厌氧反应器中的某些红螺菌科和氨基酸球菌科的微生物,可能是在厌氧条件下对氮磷同时降解起关键作用的功能菌群。 展开更多
关键词 生物分子生态学 除磷微生物 优势菌群
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混凝沉淀-HBF-二级软化沉淀处理航天炉煤气化废水
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作者 张金彪 《净水技术》 CAS 2023年第S01期200-205,共6页
结合废水特点与用户需求,将“混凝沉淀-生物固定膜复合(HBF)工艺-二级软化沉淀”组合工艺应用于煤化工综合废水(航天炉煤气化废水为主)的处理中。该工程案例中,乙二醇废水预处理新型高效厌氧脱氮生物反应器(ADN反应器)设计NO_(3)^(-)N... 结合废水特点与用户需求,将“混凝沉淀-生物固定膜复合(HBF)工艺-二级软化沉淀”组合工艺应用于煤化工综合废水(航天炉煤气化废水为主)的处理中。该工程案例中,乙二醇废水预处理新型高效厌氧脱氮生物反应器(ADN反应器)设计NO_(3)^(-)N容积负荷为1.27kgNO_(3)-N/(m^(3)·d),上升流速为2m/h,停留时间为15.1h;综合废水处理系统中,一级缺氧池设计TN容积负荷为(0.8kgTN/m^(3)·d),一级好氧池设计COD_(Cr)容积负荷为0.8kgCOD_(Cr)/(m^(3)·d),一级好氧池设计氨氮容积负荷为0.2kg氨氮/(m^(3)·d)。运行结果表明,该组合工艺对煤化工综合废水的处理效果稳定。经处理后的出水COD_(Cr)<45mg/L、TN<30mg/L、氨氮<5mg/L,出水水质满足《石油化学工业污染物排放标准》(GB315712015)表1直接排放标准及《合成氨工业水污染物排放标准》(GB134582013)表2直接排放标准。系统运行成本约为3.01元/m^(3)。 展开更多
关键词 航天炉煤气化废水 生物固定膜复合(HBF)工艺 乙二醇废水 生物反应器(ADN反应器)
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使NO_x排放量保持在9.Oppm以下的燃天然气联合循环机组
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作者 郑巧生 《锅炉技术》 北大核心 1996年第1期20-21,共2页
East Syracuse电站是第一批采用LM6000燃气轮机的商业电站之一,它解决了噪音和排放问题.该燃天然气联合循环热电联供机组为Niagara Mohawk能源公司提供97MW的电力同时向附近的Bristol—MyersSquibb公司的生产厂提供每小时达36281kg的生... East Syracuse电站是第一批采用LM6000燃气轮机的商业电站之一,它解决了噪音和排放问题.该燃天然气联合循环热电联供机组为Niagara Mohawk能源公司提供97MW的电力同时向附近的Bristol—MyersSquibb公司的生产厂提供每小时达36281kg的生产用汽. 展开更多
关键词 氮氧生物 联合循环 天然气 排放量 燃气轮机
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The Effect of Nitric Oxide on the Growth of Marine Phytoplankton 被引量:19
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作者 ZHANGZhengbin LINCai +2 位作者 LIUChunying SUNMingyi DINGHaibing 《Journal of Ocean University of Qingdao》 2003年第2期185-188,共4页
The incubation experiments of Skeletonema costatum, Dicrateria zhanjiangensis nov. sp., and Platymonas sub-cordiformis, and those of Emiliania huxleyi were carried out in the Marine Physical Chemistry Laboratory in Oc... The incubation experiments of Skeletonema costatum, Dicrateria zhanjiangensis nov. sp., and Platymonas sub-cordiformis, and those of Emiliania huxleyi were carried out in the Marine Physical Chemistry Laboratory in Ocean University of China and in the Marine Organic Geochemistry Laboratory in the University of Georgia respectively. Nitric oxide was added into the media when these marine microalgae were growing. We found the growth of these four microalgae were promoted or inhibited when nitric oxide of different concentrations was added one or two times each day during the cultivation process. The results are consistent with the influence of nitric oxide on the growth of high plants. The results show that nitric oxide may be a new factor of regulation and control for the phytoplankton growth in seawater. 展开更多
关键词 nitric oxide (NO) marine phytoplankton MICROALGAE a new factor of regulation and control
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Rectal nitric oxide as biomarker in the treatment of inflammatory bowel disease: Responders versus nonresponders 被引量:10
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作者 Tryggve Ljung Sofie Lundberg +5 位作者 Mark Varsanyi Catharina Johansson Peter T Schmidt Max Herulf Jon O Lundberg Per M Hellstr(o|¨)m 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第21期3386-3392,共7页
AIM: To explore rectal nitric oxide (NO) as biomarker of treatment response in ulcerative colitis (UC) and Crohn's disease (CD), and examine relationships between rectal NO, mucosal expression of NO synthases ... AIM: To explore rectal nitric oxide (NO) as biomarker of treatment response in ulcerative colitis (UC) and Crohn's disease (CD), and examine relationships between rectal NO, mucosal expression of NO synthases (NOS), and pro-inflammatory cytokines. METHODS: Twenty-two patients with UC and 24 with CD were monitored during steroid treatment. Rectal NO levels were measured and clinical activities were assessed on days 1, 3, 7 and 28. Mucosal presence of NOS and pro-inflammatory cytokines were analyzed by immunohistochemistry and RT-PCR. RESULTS: Active UC and CD displayed markedly increased rectal NO levels (10950 ± 7610 and 5 040 ± 1 280 parts per billion (ppb), respectively) as compared with the controls (154 ± 71 ppb, P 〈 0.001). Rectal NO correlated weakly with disease activity in both UC and CD (r = 0.34 for UC and r = 0.48 for CD, P 〈 0.01). In 12 patients, a steroid-refractory course led to colectomy. These patients had only slightly increased NO levels (UC: 620 ± 270 ppb; CD: 1260 ± 550 ppb) compared to those with a therapeutic response (UC: 18860 ± 530 ppb, P 〈 0.001, CD: 10060 ± 3200 ppb, P 〈 0.05). CONCLUSION: Rectal NO level is a useful biomarker of treatment response in IBD as low NO levels predicts a poor clinical response to steroid treatment. 展开更多
关键词 Crohn's disease CytokJnes Nitric oxide STEROIDS Ulcerative colitis
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Polypeptide from Chlamys farreri inhibits UVB-induced apoptosis of HaCaT cells via iNOS/NO and HSP90 被引量:4
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作者 张正洋 刘小金 +3 位作者 刘拓 闫琳 王跃军 王春波 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期594-599,共6页
Polypeptide from Chlamys farreri(PCF) is a novel marine bioactive product that was isolated from the gonochoric Chinese scallop Chlamys farreri,and was found to be an effective antioxidant in our recent studies.In thi... Polypeptide from Chlamys farreri(PCF) is a novel marine bioactive product that was isolated from the gonochoric Chinese scallop Chlamys farreri,and was found to be an effective antioxidant in our recent studies.In this study,we investigated the effect of PCF on ultraviolet B(UVB)-induced apoptosis of HaCaT cells and the intracellular signaling pathways involved.Pretreatment with the inducible nitric oxide synthase(iNOS) inhibitor S-methylisothiourea sulfate inhibited UVB-induced apoptosis,indicating that iNOS and NO play important roles in apoptosis.On the other hand,the inhibition of UVB-induced apoptosis in the immortalized keratinocyte(HaCaT) cells by PCF was estimated using a DNA ladder.PCF treatment inhibited UVB-induced iNOS activation,as determined by RT-PCR,NO production,as determined by ESR,and up-regulated heat shock protein(HSP) 90 activation,as determined by Western blotting.Our results indicate that iNOS and NO are involved in UVB-induced apoptosis of HaCaT cells and the protective effect of PCF against UVB irradiation is exerted by suppressing the expression of iNOS,followed by inhibition of NO release and enhanced activation of HSP90. 展开更多
关键词 apoptosis HaCaT cells HSP INOS/NO Polypeptide from Chlamysfarreri (PCF) ultraviolet B (UVB)
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Science Letters:Alterations in seedling vigour and antioxidant enzyme activities in Catharanthus roseus under seed priming with native diazotrophs 被引量:12
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作者 KARTHIKEYAN B. JALEEL C.A. +1 位作者 GOPI R. DEIVEEKASUNDARAM M. 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第7期453-457,共5页
An experiment was conducted on Catharanthus roseus to study the effect of seed treatments with native diazotrophs on its seedling growth and antioxidant enzyme activities. The treatments had significant influence on v... An experiment was conducted on Catharanthus roseus to study the effect of seed treatments with native diazotrophs on its seedling growth and antioxidant enzyme activities. The treatments had significant influence on various seedling parameters. There is no significant influence on dry matter production with the diazotrophs, Azospirillum and Azotobacter. However, the vital seedling parameters such as germination percentage and vigour index were improved. Azotobacter treatment influenced maximum of 50% germination, whereas Azospirillum and Azotobacter were on par with C. roseus with respect to their vigour index. There was significant difference in the population of total diazotrophs. Azospirillum and Azotobacter between rhizosphere and non-rhizosphere soils of C. roseus had the same trend and were observed at various locations of the study. The activities of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POX) and catalase (CAT) were increased to a significant extent due to the treatment with diazotrophs. 展开更多
关键词 RHIZOSPHERE Non-rhizosphere AZOSPIRILLUM AZOTOBACTER Antioxidant enzyme Catharanthus roseus
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How to protect liver graft with nitric oxide 被引量:11
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作者 Hassen Ben Abdennebi Mohamed Amine Zaoualí +2 位作者 Izabel Alfany-Fernandez Donia Tabka Joan Roselló-Catafau 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第24期2879-2889,共11页
Organ preservation and ischemia reperfusion injury associated with liver transplantation play an important role in the induction of graft injury. One of the earliest events associated with the reperfusion injury is en... Organ preservation and ischemia reperfusion injury associated with liver transplantation play an important role in the induction of graft injury. One of the earliest events associated with the reperfusion injury is endothelial cell dysfunction. It is generally accepted that endothelial nitric oxide synthase (e-NOS) is cell-pro- tective by mediating vasodilatation, whereas inducible nitric oxide synthase mediates liver graft injury after transplantation. We conducted a critical review of the literature evaluating the potential applications of regulating and promoting e-NOS activity in liver preservation and transplantation, showing the most current evidence to support the concept that enhanced bioavailability of NO derived from e-NOS is detrimental to ameliorate graft liver preservation, as well as preventing subse- quent graft reperfusion injury. This review deals mainly with the beneficial effects of promoting "endogenous" pathways for NO generation, via e-NOS inducer drugs in cold preservation solution, surgical strategies such as ischemic preconditioning, and alternative "exogenous" pathways that focus on the enrichment of cold storage liquid with NO donors. Finally, we also provide a basic bench-to-bed side summary of the liver physiology and cell signalling mechanisms that account for explaining the e-NOS protective effects in liver preservation and transplantation. 展开更多
关键词 Cold ischemia reperfusion injury Endotheli-al nitric oxide synthase Nitric oxide Liver graft preser-vation Ischemic preconditioning Liver transplantation
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A Modified Oxidation Ditch with Additional Internal Anoxic Zones for Enhanced Biological Nutrient Removal 被引量:5
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作者 LIU Wei YANG Dianhai XU Li SHEN Changming 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第2期192-198,共7页
A novel modified pilot scale anaerobic oxidation ditch with additional internal anoxic zones was operated experimentally, aiming to study the improvement of biological nitrogen and phosphorus removal and the effect of... A novel modified pilot scale anaerobic oxidation ditch with additional internal anoxic zones was operated experimentally, aiming to study the improvement of biological nitrogen and phosphorus removal and the effect of enhanced denitrifying phosphorus removal in the process. Under all experimental conditions, the anaero- bic-oxidation ditch with additional internal anoxic zones and an internal recycle ratio of 200% had the highest nutrient removal efficiency. The effluent NH4 -N, total nitrogen (TN), PO3 -P and total phosphorus (TP) contents were 1.2 mg.L-1, 13 mg.L 1, 0.3 mg.L -1 and 0.4 mg.L-1, respectively, all met the discharge standards in China. The TN and TP removal efficiencies were remarkably improved from 37% and 50% to 65% and 88% with the presence of additional internal anoxic zones and internal recycle ratio of 200%. The results indicated that additional internal anoxic zones can optimize the utilization of available carbon source from the anaerobic outflow for denitrification. It was also found that phosphorus removal via the denitrification process was stimulated in the additional internal anoxic zones, which was beneficial for biological nitrogen and phosphorus removal when treating wastewater with a limited carbon source. However, an excess internal recycle would cause nitrite to accumulate in the system. This seems to be harmful to biological phosphorus removal. 展开更多
关键词 internal anoxic zones internal recycle carbon source NITRATE PHOSPHORUS
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Expression of endothelial nitric oxide synthase and vascular endothelial growth factor in association with neovascularization in human primary astrocytoma 被引量:2
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作者 潘剑威 詹仁雅 +2 位作者 童鹰 周永庆 章明 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第7期693-698,共6页
Objective: To investigate the relationship between the expression of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF) and angiogenesis in primary astrocytoma. Methods: Thirty-seven p... Objective: To investigate the relationship between the expression of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF) and angiogenesis in primary astrocytoma. Methods: Thirty-seven primary astrocytomas and 4 astrocytic hyperplasia samples were collected and divided into three groups according to histological grade. The expression of eNOS, VEGF and factorⅧ related antigen (FⅧRAg) were assayed by immunohistochemistry. Microvascular density was assessed by FⅧRAg immunoreactivity. The intensity of immunoreactivity was graded according to the percentage of positive tumor cells. Results: No eNOS and VEGF were expressed in the astrocytes and vascular endothelium in astrocytic hyperplasia. The expression of eNOS or VEGF was light in low-grade astrocytoma and strong in glioblastoma. eNOS expression in astrocytoma was very positively correlated with VEGF. eNOS and VEGF expression in anaplastic astrocytoma was median in contrast to the low grade astrocytoma and glioblastoma. Lower microvascular density was found in low grade astrocytoma than that in higher grade malignant ones. The expressions of eNOS and VEGF were correlated with microvascular density and tumor malignancy. Conclusion: This finding suggests that eNOS and VEGF may have cooperative effect in tumor angiogenesis and play an important role in the pathogenesis of primary astrocytoma. 展开更多
关键词 Endothelial nitric oxide synthase Vascular endothelial growth factor Density of microvessels Primary astrocytoma
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The correlation between nitrogen species in coke and NO_x formation during regeneration 被引量:6
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作者 Teng Li Chaohe Yang +3 位作者 Xiaobo Chen Libo Yao Wei Liang Xuemei Ding 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第5期606-611,共6页
Nitrogen oxides (NOx) emission during the regeneration ofcoked fluid catalytic cracking (FCC) catalysts is an en- vironmental issue. In order to identify the correlations between nitrogen species in coke and diffe... Nitrogen oxides (NOx) emission during the regeneration ofcoked fluid catalytic cracking (FCC) catalysts is an en- vironmental issue. In order to identify the correlations between nitrogen species in coke and different nitrogen- containing products in tail gas, three coked catalysts with multilayer structural coke molecules were prepared in a fixed bed with model compounds (o-xylene and quinoline) at first. A series of characterization methods were used to analyze coke, including elemental analysis, FT-IR, XPS, and TG-MS. XPS characterization indicates all coked catalysts present two types of nitrogen species and the type with a higher binding energy is related with the inner part nitrogen atoms interacting with acid sites. Due to the stronger adsorption ability on acid sites for basic nitrogen compounds, the multilayer structural coke has unbalanced distribution of carbon and ni- trogen atoms between the inner part and the outer edge, which strongly affects gas product formation. At the early stage of regeneration, oxidation starts from the outer edge and the product NO can be reduced to N2 in high CO concentration. At the later stage, the inner part rich in nitrogen begins to be exposed to 02. At this period, the formation of CO decreases due to lack of carbon atoms, which is not beneficial to the reduction of NO. There- fore, nitrogen species in the inner part of multilayer structural coke contributes more to NOx formation. Based on the multilayer structure model of coke molecule and its oxidation behavior, a possible strategy to control NOx emission was discussed merely from concept. 展开更多
关键词 NOx Basic nitrogen compounds FCC catalyst COKING REACTION MULTILAYER
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Effects of IGF-Ⅱ on promoting proliferation and regulating nitric oxide synthase gene expression in mouse osteoblast-like cell 被引量:2
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作者 孙伟莲 陈莉丽 +1 位作者 严杰 余钟声 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第7期699-704,共6页
Objective: To investigate the effects of insulin-like growth factor Ⅱ (IGF-Ⅱ) on promoting cell proliferation, regulating levels of cellular nitric oxide (NO) and mRNA transcriptions of inducible nitric oxide syntha... Objective: To investigate the effects of insulin-like growth factor Ⅱ (IGF-Ⅱ) on promoting cell proliferation, regulating levels of cellular nitric oxide (NO) and mRNA transcriptions of inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS) in mouse osteoblast-like cells. Methods: Mouse osteoblastic cell line MC3T3-E1 was selected as the effective cell of IGF-Ⅱ. After the cells were treated with IGF-Ⅱ at different concentrations for different time duration,3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay was used to examine cell proliferation,and nitrate reductase method was applied to detect NO concentrations in cell culture supernatants and quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) was employed to determine transcription levels of cellular iNOS and eNOS mRNAs. Results: After the MC3T3-E 1 cells were treated with IGF-Ⅱ at concentration of 1 ng/ml for 72 h, 10 and 100 ng/ml for 24,48 and 72 h respectively, all the MTT values increased (P<0.05 or P<0.01) with obvious dosage-time dependent pattern. NO levels of the MC3T3-E1 cells treated with 100 ng/ml IGF-Ⅱ for 48 h, and with 1, 10 and 100 ng/ml IGF-Ⅱ for 72 h were remarkably lower than that of the normal control, respectively (P<0.05 or P<0.01). After the cells were treated with 100 ng/ml IGF-Ⅱ for 48 h cellular iNOS mRNA levels were significantly decreased (P<0.01). But the levels of eNOS mRNA in the cells treated with each of the used IGF-Ⅱ dosages for different time duration did not show any differences compared with the normal control (P>0.05).Conclusion: IGF-Ⅱ at different concentrations could promote proliferation of mouse MC3T3-E1 cell. This cell proliferation promotion was associated with the low NO levels maintained by IGF-Ⅱ. Higher concentration of IGF-Ⅱ could down-regulate iNOS gene expression at the level of transcription but not affect transcription of eNOS mRNA, which might be one of the mechanisms for IGF-Ⅱ maintenance of the low NO levels in MC3T3-E 1 cells. 展开更多
关键词 Insulin-like growth factor II OSTEOBLAST PROLIFERATION Nitric oxide synthase Nitric oxide Regulation
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Application of Stable Isotope Techniques in Studies of Carbon and Nitrogen Biogeochemical Cycles of Ecosystem 被引量:7
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作者 SUN Zhigao MOU Xiaojie +3 位作者 LI Xinhua WANG Lingling SONG Hongli JIANG Huanhuan 《Chinese Geographical Science》 SCIE CSCD 2011年第2期129-148,共20页
Stable isotope techniques have been proved useful as tools for studying the carbon (C) and nitrogen (N) biogeochemical cycles of ecosystem. This paper firstly introduced the basic principles and the distribution chara... Stable isotope techniques have been proved useful as tools for studying the carbon (C) and nitrogen (N) biogeochemical cycles of ecosystem. This paper firstly introduced the basic principles and the distribution characteristics of stable isotope, then reviewed the recent advances and applications of stable isotope in the C and N biogeochemical cycles of ecosystem. By applying the 13 C natural abundance technique, ecologists are able to understand the photosynthetic path and CO 2 fixation of plants, the CO 2 exchange and C balance status of ecosystem, the composition, distribution and turnover of soil organic C and the sources of organic matter in food webs, while by using the 13 C labeled technique, the effects of elevated CO 2 on the C processes of ecosystem and the sources and fate of organic matter in ecosystem can be revealed in detail. Differently, by applying the 15 N natural abundance technique, ecologists are able to analyze the biological N 2 -fixation, the N sources of ecosystem, the N transformation processes of ecosystem and the N trophic status in food webs, while by using the 15 N labeled technique, the sources, transformation and fate of N in ecosystem and the effects of N input on the ecosystem can be investigated in depth. The applications of both C and N isotope natural abundance and labeled techniques, combined with the elemental, other isotope ( 34 S) and molecular biomarker information, will be more propitious to the investigation of C and N cycle mechanisms. Finally, this paper concluded the problems existed in current researches, and put forward the perspective of stable isotope techniques in the studies on C and N biogeochemical cycles of ecosystem in the future. 展开更多
关键词 stable isotope isotope fractionation isotope natural abundance biogeochemical cycle CARBON NITROGEN
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A Combined System for Biological Removal of Nitrogen and Carbon from Nylon-6 Production Wastewater
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作者 刘芳 刘国华 +2 位作者 田晴 张曼 陈季华 《Journal of Donghua University(English Edition)》 EI CAS 2007年第6期700-706,共7页
A combined system consisting of hydrolysis acidification, denitrification and nitrification reactors was used to remove carbon and nitrogen from the nylon - 6 production wastewater, which was characterized by good bio... A combined system consisting of hydrolysis acidification, denitrification and nitrification reactors was used to remove carbon and nitrogen from the nylon - 6 production wastewater, which was characterized by good biodegradability and high nitrogen concentration. The influences of Chemical Oxygen Demand (COD) in the influent, recirculation ratio, Hydraulic Residence Time (HRT) and Dissolved Oxygen (DO) concentration on the system performances were investigated. From results it could be seen that good performances have been achieved during the overall experiments periods, and COD, Total Nitrogen (TN), NH^+ -N and Suspended Solids (SS) in the effluent were 53, 16, 2 and 24 mg· L^-1, respectively, which has satisfied the first standard of wastewater discharge established by Environmental Protection Agency (EPA) of China. Furthermore, results showed that operation factors, viz. COD in the influent, recirculation ratio, HRT and DO concentration, all had important influences on the system performances. 展开更多
关键词 Nylon-6 production wastewater hydrolysis acidification submerged biofilm reactor biological nitrogen removal
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