半滑舌鳎组织器官中一氧化氮含量和一氧化氮合酶活性的测定

[目的]研究半滑舌鳎不同组织器官中一氧化氮(NO)含量和不同类型一氧化氮合酶(NOS)活性.[方法]采用Griess试剂法测定NO含量,采用化学比浊法测定NOS的活性.[结果]诱导型一氧化氮合酶(iNOS)在肌肉组织中活性最高,为28.774±4.10U/mgprot,依次为肠、脑、肝脏、头肾、鳃、中肾、脾脏、心脏.肠和脑之间以及肝脏和头肾之间iNOS的活性不存在显著性差异,而其他组织器官之间iNOS的活性都存在显著性差异.结构型一氧化氮合酶(cNOS)在肠组织中活性最高,为55.979±5.048 U/mgprot.所测组织器官中cNOS活性都存在显著性差异.NO含量在脾脏中最高,为38.540±4.535μmol/L.脾脏、头肾、肝脏之间,以及脑、心脏、中肾之间NO含量不存在显著性差异,而其他组织器官之间NO含量都存在显著性差异.[结论]不同组织器官中NO含量和NOS活性不同,这可能与组织器官功能有着密切联系.     

Viscosities of ternary systems Y（NO_3）_3＋La（NO_3）_3＋H_2O,La（NO_3）_3＋Ce（NO_3）_3＋H_2O,La（NO_3）_3＋Nd（NO_3）_3＋H_2O and their binary subsystems at different temperatures

Viscosities were measured for the ternary systems Y(NO3)3+La(NO3)3+H2O, La(NO3)3+Ce(NO3)3+H2O, and La(NO3)3+Nd(NO3)3+ H2O and their binary subsystems Y(NO3)3+H2O, La(NO3)3+H2O, Ce(NO3)3+H2O, and Nd(NO3)3+H2O at 293.15, 298.15 and 308.15 K. The results were used to test the applicability of simple equations for the viscosity of the mixed solutions. The predictions agreed well with measured values, implying that the viscosities of the examined electrolyte solutions could be related to those of their constituent binary solutions using these simple equations.     

一氧化氮在脱落酸和黑暗诱导蚕豆气孔关闭中的作用

[目的]研究一氧化氮(NO)在脱落酸(ABA)和黑暗诱导的蚕豆(Vicia faba)气孔关闭中的作用.[方法]以蚕豆叶片下表皮为材料,借助表皮条分析和激光扫描共聚焦显微镜技术对NO在ABA和黑暗诱导的气孔关闭中的作用进行了探索.[结果] ABA和黑暗都能诱导蚕豆气孔关闭,而且ABA和黑暗诱导都能提高保卫细胞胞质内的NO水平.NO专一性清除剂2,4-羧基苯-4,4,5,5-四甲基咪唑-1-氧-3-氧化物(cPTIO)、一氧化氮合酶(NOS)抑制剂NG-氮-L-精氨酸-甲酯(L-NAME)能够大大抵消ABA和黑暗诱导气孔关闭的效应,并能阻断ABA和黑暗诱导的气孔保卫细胞内NO水平的提高,表明NO是ABA和黑暗诱导蚕豆气孔关闭的共同信号分子.[结论]该研究可为探索保卫细胞信号转导网络积累一定的资料,并为提高植物抗逆能力和促进农业生产提供理论依据.     

CeY分子筛的制备及其吸附脱硫性能研究

采用水热离子交换法制备CeY分子筛,讨论了交换温度、交换时间、NaY分子筛与Ce(NO3)3溶液固液比、Ce(NO3)3溶液浓度对Ce3+交换量的影响;考察了不同Ce3+交换量CeY分子筛的吸附脱硫性能;研究了吸附温度、吸附时间对NaY/Cu(I)Y/CeY分子筛吸附脱硫性能的影响;借助于IR表征手段,分析了模拟燃油中苯和噻吩物种在CeY分子筛和Cu(I)Y分子筛的吸附,结果表明,CeY分子筛的脱硫效率最高(达95.6%),同时对含苯模拟油中的噻吩吸附具有选择性;Cu(I)Y分子筛由于苯和噻吩产生的竞争吸附,在含苯模拟油中脱硫效率有明显降低.     

纳米Y_(0.7)Ce_(0.1)Sr_(0.2)M_(1-x)Cu_xO_3(M=Fe,Mn)的制备、表征及其对NO+CO的催化活性

为探究纳米钙钛矿型复合氧化物ABO3中不同B位元素及Cu的掺杂量对催化剂的结构、形貌、表面性质和催化活性的影响规律及原因,并优化出具有更好活性的催化剂,采用柠檬酸-溶胶-凝胶法制备得到8个钙钛矿型复合氧化物Y0.7Ce0.1Sr0.2Fe1-xCuxO3和Y0.7Ce0.1Sr0.2Mn1-xCuxO3(x=0.1~0.4),通过X射线衍射(XRD)、扫描电镜(SEM)、比表面积(BET)、X射线光电子能谱(XPS)等分析方法对其进行了表征,并测试了8个样品对CO+NO的催化活性。结果表明,在Fe、Mn两个系列中,x=0.3时的两个样品对CO+NO分别具有最高的催化活性,Y0.7Ce0.1Sr0.2Fe0.7Cu0.3O3对NO和CO的转化率均在225℃时达到100%,而Y0.7Ce0.1Sr0.2Mn0.7Cu0.3O3对NO和CO的转化率则分别在325℃和225℃时达到100%。Y0.7Ce0.1Sr0.2Fe0.7Cu0.3O3的催化活性优于Y0.7Ce0.1Sr0.2Mn0.7Cu0.3O3,这是由于Fe4+/Fe3+的摩尔比高于Mn4+/Mn3+,并且Y0.7Ce0.1Sr0.2Fe0.7Cu0.3O3中所有Ce4+/Ce3+、Cu+/Cu2+和OA/OL的摩尔比均高于Y0.7Ce0.1Sr0.2Mn0.7Cu0.3O3中相应的摩尔比,而这些因素均有利于NO+CO的催化活性。通过适量的Cu取代B位离子可提高催化剂对NO+CO的氧化还原性,同时Cu的掺杂对于Fe、Mn两个系列中OA/OL的摩尔比具有不同的影响。     

Low temperature selective catalytic reduction of NO by C3H6 over Ce Ox loaded on AC treated by HNO3

The activated carbons from coal were treated by HNO3(named as NAC) and used as carriers to load 7% Ce(named as Ce(0.07)/NAC) by impregnation method. The physical and chemical properties were investigated by thermogravimetric-differential thermal analysis(TG-DTA), Brunauer-Emmett-Teller(BET), X-ray diffraction(XRD), X-ray photoelectron spectra(XPS), scanning electron microscopy(SEM) and NH3-temperature programmed desorption(NH3-TPD) and NO-temperature programmed desorption techniques. The catalytic activities of Ce(0.07)/NAC were evaluated for the low temperature selective catalytic reduction(SCR) of NO with C3H6 using temperature-programmed reaction(TP-reaction) in NO, C3H6, O2 and N2 as a balance. The results showed that the specific surface area of Ce(0.07)/NAC was 850.8 m2/g and less than NAC, but Ce oxides could be dispersed highly on the activated carbons. Ce oxides could change acid sites and NO adsorption as well as oxygen-containing functional groups of activated carbons, and Ce4+ and Ce3+ coexisted in catalysts. The conversion of NO with C3H6 achieved 70% at 280 °C over Ce(0.07)/NAC, but with the increase of O2 concentration, heat accumulation and nonselective combustion were exacerbated, which could cause surface ashing and roughness, resulting in a sharp decrease of catalytic activities. The optimum O2 concentration used in the reaction system was 3% and achieved the high conversion of NO and the widest temperature window. The conversion of NO was closely related to the NO concentrations and [NO]/[C3H6] ratios, and the stoichiometric number was just close to 2:1, but the presence of H2 O could affect the denitration efficiency of catalyst.     

铈改性固体超强酸SO2-4/Sb2O3的制备及催化性能研究

以SbCl3为原料经醇化水解制 Sb2O3前体氧化物,通过浸渍一定量的(NH4)2SO4和掺杂Ce4+制备了一种新型催化剂SO42-/ Sb2O3/Ce4+ .以催化合成乙酸苄酯为探针反应,考察了(NH4)2SO4的浓度、Ce(NO3)4 的浓度、焙烧温度等因素对其催化性能的影响,并采用IR、TG/DTA、Hammett法等对其进行表征.结果表明,1.5 mol·L-1的(NH4)2SO4和含Ce(NO3)4 2.8%的混合液浸渍锑前体氧化物,经110℃烘干后,于350℃焙烧2 h所得的催化剂活性最好,其酯化率达到97%..     

Roles of Ceria on Base Metal Oxide Catalysts——NO+CO Reaction

A microreactor system was used to study the catalytic reaction of NO+CO→1/2 N_2+CO_2 over Cu,Fe,Mn,Cr,and Ce oxides supported on alumina,and the effect of adding Ce in supported Cu-M-O(M=Mn,Feand Cr) catalysts on their catalytic activities for the topic reaction and the concentration of N_2O produced.Itwas found that the catalytic activity order of the single-element oxide is:CuO>Fe_2O_3≈Cr_2O_3>MnO_2>CeO_2>NiO.Cu-Mn-O is more active than CuO,and Cu-Fe-O is more active than Cu-Mn-O andCu-Cr-O for NO+CO reaction.This study shows that the addition of Ce in supported Cu-M-O can promotetheir catalytic activities Jot the topic reaction,which makes the reaction of 2NO+CO→N_2O+CO_2 fast,andN_2O is an intermediate compound produced during NO+CO reaction.     

pH对碳酸铈粒子团聚的影响

在不同的(NH4)2CO3和Ce(NO3)3摩尔比值R、初始料液Ce(NO3)3溶液的pH以及(NH4)2CO3加料时间条件下制备了Ce2(CO3)3粒子,并用SEM和Zeta电位仪对其进行表征。结果表明,溶液pH对Ce2(CO3)3粒子形貌无影响,只是使得溶液离子浓度及双电层厚度发生改变,进而引发Ce2(CO3)3粒子的团聚。当R=1.6、pH=4、加料时间1h时得到的Ce2(CO3)3形貌最好,颗粒分散性好。     

Ce~(3 )对大白鼠肝细胞和肝脏ATPase的影响

研究了 Ce3 对肝细胞和肝脏 ATPase的影响。结果表明 ,Ce3 对肝细胞 ATPase的影响不显著 ;长期用含 Ce3 饲料喂养大白鼠 ,低浓度的 Ce3 刺激肝脏 ATPase的活性 ,高浓度的 Ce3 则抑制肝脏 ATPase的活性     

Spectroscopy Study on Crystal Structure of Ce（NO3）3 （phen）2 and Interactions of Ce（NO3）3 （phen）2 with DNA

Inrecentyears ,Komiyaetal.[1] havefoundthatrareearthsionsmaybeoneofthestrongestcutre agentsofnucleicacids .Theexperimentalresults ,thatrareearthsrepresscancersonwholeanimalbodiesandonhumanbodies(invitro) ,indicatedthatrareearthselementsactuallyhavestrongf…     

硝酸铈对水稻种子活力和萌发期间酶活性的影响

用２．５～３０ｍｇ／ＬＣｅ（ＮＯ３）３浸泡水稻种子能明显提高稻种的活力,促进幼苗的生长。这与Ｃｅ提高稻种萌发期间的呼吸速率、增加淀粉酶、蛋白酶和脂肪酶等水解酶的活性有密切关系。其中用１０ｍｇ／Ｌ浓度的Ｃｅ（ＮＯ３）３浸种效果最好。当浓度超过５０ｍｇ／Ｌ时,种子的萌发、呼吸作用及三种酶的活性均受到抑制。     

Effects of thermal injury on production of nitric oxide in rat heart

To elucidate the relationship between thermal injury and production of nitric oxide (NO), we measured the levels of heart No2-/NO3- (the stable and products of NO) and GMP in rats with full thickness burn of 30% TBSA. A higher level of heart tissue NO2-/NO3- was observed from 3 to 24 hours after burn injury. Parallel to the changes of NO2-/NO3-, there were increases of tissue cGMP level and heart tissue water content in burned rats. L-NMMA, a specific inhibitor of NO synthetase (NOS), can block the rise of heart NO2-/NO3- and the enhancement of heart water content. The results indicate that the heart injury caused by burn injury may be associated with induction of NOS and formation of NO.     

Regulation of the endogenous NO pathway by prolonged inhaled NO in rats

Nitric oxide (NO) modulates the endogenous NO-cGMP pathway. We determined whether prolonged inhaled NO downregulates the NO-cGMP pathway, which may explain clinically observed rebound pulmonary hypertension. Rats were placed in a normoxic (N; 21% O2) or hypoxic (H; 10% O2) environment with and without inhaled NO (20 parts/million) for 1 or 3 wk. Subsequently, nitric oxide synthase (NOS) and soluble guanylate cyclase (GC) activity and endothelial NOS (eNOS) protein levels were measured. Perfusate cGMP levels and endothelium-dependent and -independent vasodilation were determined in isolated lungs. eNOS protein levels and NOS activity were not altered by inhaled NO in N or H rats. GC activity was decreased by 60 +/- 10 and 55 +/- 11% in N and H rats, respectively, after 1 wk of inhaled NO but was not affected after 3 wk. Inhaled NO had no effect on perfusate cGMP in N lungs. Inhaled NO attenuated the increase in cGMP levels caused by 3 wk of H by 57 +/- 11%, but there was no rebound in cGMP after 24 h of recovery. Endothelium-dependent vasodilation was not altered, and endothelium-independent vasodilation was not altered (N) or slightly increased (H, 10 +/- 3%) by prolonged inhaled NO. In conclusion, inhaled NO did not alter the endogenous NO-cGMP pathway as determined by eNOS protein levels, NOS activity, or endothelium-dependent vasodilation under N and H conditions. GC activity was decreased after 1 wk; however, GC activity was not altered by 3 wk of inhaled NO and endothelium-independent vasodilation was not decreased.