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1.
赵丽萍  冯纪南  黄红英  邓斌 《安徽农业科学》2011,39(22):13334+13418-13334,13418
[目的]研究[La(C9H6NO)2(C6H5COO)].H2O浸种对水稻种子萌发及幼苗生长的影响。[方法]采用不同浓度(0.005×10-3、时,则抑制种子萌发及幼苗生长。[结论]适当浓度的[La(C9H6NO)2(C6H5COO)].H2O可促进种子萌发及幼苗生长。0.010×10-30、.050×10-3、0.100×10-3、0.300×10-3 mol/L)的[La(C9H6NO)2(C6H5COO)].H2O水溶液处理水稻种子。[结果][La(C9H6NO)2(C6H5COO)].H2O浓度为0.005×10-3~0.100×10-3mol/L时,促进种子萌发及幼苗生长,浓度大于0.300×10-3 mol/L时,则抑制种子萌发及幼苗生长。[结论]适当浓度的[La(C9H6NO)2(C6H5COO)]·H2O可促进种子萌发及幼苗生长。  相似文献   

2.
李源  魏小红  朱蕾  毛亚斌 《安徽农业科学》2009,37(11):4942-4944
[目的]探讨NO、H2O2在调控镉胁迫下蚕豆的生理生化机理。[方法]采用水培方法,研究了硝普钠(SNP,作为外源NO供体)、双氧水(H2O2)及其体积比例组合(1∶1)浸泡处理对镉胁迫下蚕豆种子活力的影响;并采用土培方法,研究了上述3种处理对镉胁迫下蚕豆幼苗氧化损伤的保护效应。[结果]与SNP和H2O2单独处理相比,二者互作处理可显著增强镉胁迫下蚕豆种子活力,从而缓解了重金属镉对蚕豆种子萌发的毒害作用;并且SNP和H2O2互作处理对缓解镉胁迫下蚕豆幼苗的氧化损伤存在正协同效应,主要表现在增强了根系活力,提高了叶绿素含量和脯氨酸含量,并降低了MDA含量(P〈0.05)。[结论]NO和H2O2的互作处理更有效地减弱了叶绿素的降解反应,提高了叶片细胞的渗透调节能力和耐毒能力。  相似文献   

3.
嘧霉胺对环境生物毒性及安全评价   总被引:3,自引:0,他引:3  
测定了嘧霉胺农药对6种有代表性的非靶生物蜜蜂、鹌鹑、家蚕、斑马鱼、泽蛙、蚯蚓的急性毒性,并进行了安全性评价。试验结果表明:嘧霉胺对蜜蜂接触LD50(48 h)>100μg/蜂,经口LC50(48 h)>1333 mg/L,对雌、雄鹌鹑LC50(7 d)>1000 mg/kg,对家蚕、斑马鱼、泽蛙的LC50(96 h)分别为727、25.1、27.7 mg/L,对蚯蚓LC50(14 d)为206 mg/kg干土。该农药对蜜蜂、鹌鹑、家蚕、斑马鱼、泽蛙、蚯蚓毒性均为低毒级。  相似文献   

4.
Nearly quantitative conversion of nitric oxide (NO) into N(2)H(4)CO has been obtained in the reduction of NO with carbon monoxide and hydrogen over platinum and rhodium catalysts. Depending on the temperature of collection, N(2)H(4)CO is isolated as ammonium cyanate or its isomer, urea. The process is an effective way of recovering fixed nitrogen from dilute industrial streams containing NO. Ammonium cyanate may play a role in the reduction of NO in automotive exhaust control.  相似文献   

5.
The Bennett radio-frequency ion mass spectrometer on the Pioneer Venus orbiter is returning the first direct composition evidence of the processes responsible for the formation and maintenance of the nightside ionosphere. Early results from predusk through the nightside in the solar zenith angle range 63 degrees (dusk) to 120 degrees (dawn) reveal that, as on the dayside, the lower nightside ionosphere consists of F(1)and F(2) layers dominated by O(2)(+) and O(+), respectively. Also like the dayside, the nightside composition includes distributions of NO(+), C(+), N(+), H(+), He(+), CO(2)(+), and 28(+) (a combination of CO(+) and N(2)(+)). The surprising abundance of the nightside ionosphere appears to be maintained by the transport of O(+) from the dayside, leading also to the formation of O(2)(+) through charge exchange with CO(2). Above the exobase, the upper nightside ionosphere exhibits dramatic variability in apparent response to variations in the solar wind and interplanetary magnetic field, with the ionopause extending to several thousand kilometers on one orbit, followed by the complete rertnoval of thermal ions to altitudes below 200 kilometers on the succeeding orbit, 24 hours later. In the upper ionosphere, considerable structure is evident in many of the nightside ion profiles. Also evident are horizontal ion drifts with velocities up to the order of 1 kilometer per second. Whereas the duskside ionopause is dominated by O(+) H(+) dominates the topside on the dawnside of the antisolar point, indicating two separate regions for ion depletion in the magnetic tail regions.  相似文献   

6.
[目的]提高竹红菌素的产量。[方法]对从野生竹红菌中分离出产红色素的竹红菌菌株进行液体培养,研究适宜竹红菌生长的培养基、碳源、氮源和pH值。[结果]竹红菌在牛肉膏培养基上生长最快,色素分泌最多,颜色最浓。供试5种碳源处理中,竹红菌在乳糖培养基上生长最快,分泌色素最多,其次是麦芽糖、D-木糖、可溶性淀粉。不同氮源对竹红菌生长的影响有明显的差异。NH4NO3培养基上竹红菌生长速度最快,色素分泌多,NH4Cl培养基上长势最慢。不同pH值对竹红菌生长影响较明显,竹红菌在pH值3~9范围内都能生长,pH值为6时长势最好,色素分泌最多。[结论]竹红菌在牛肉膏培养基上生长速度最快,最易利用的碳源和氮源是乳糖、NH4NO3,pH值3~9时均可生长,以pH值为6最适合。  相似文献   

7.
Organic combustion products generated by the lunar module descent engine, which burns a 1:1 mixture of unsymmetrical dimethylhydrazine fuel and nitrogen tetroxide oxidizer, have been analyzed. The major gaseous combustion products found were ammonia, water, carbon monoxide, nitrous oxide, oxygen, carbon dioxide, and nitric oxide. The minor products were acetylene, hydrogen cyanide, ethylene, formaldehyde, propadiene, ketene, cyanous acid, hydrazoic acid, various methylamines, acetaldehyde, methyl nitrite, formic acid, nitrous acid, butadiyne, nitrilohydrazines, nitromethane, and nitrosohydrazines with other oxidized derivatives of unsymmetrical dimethylhydrazine and hydrazine. The ion intensities of the various species in all mass spectra were estimated as the following concentrations: the gases (NH(3), H(2)O, CO, NO, O(2), CO(2), and NO(2)), 87.7 percent; compounds of C, H, and O, 6.0 percent; and compounds of C, H, and N (with traces of O), 5.8 percent.  相似文献   

8.
The fluidity of a simple liquid is proportional to its degree of expansion over the volume, V(0), at which its molecules are so crowded as to inhibit self-diffusion and viscous (as distinguished from plastic) flow. The equation of proportionality is 1/eta = B[(V - V(0))/V(0)] where eta is the viscosity and V is the molal volume. Values of B are the same for normal paraffins from C(3)H(8) to C(7)H(16) and then decrease progressively as the paraffin lengths increase. Values for other liquids, C(6)H(6), CCl(4), P(4), CS(2), CHCl(3), and Hg, appear to vary with repulsive forces. liquids can be moderately fluid when expanded by less than 10 percent; this shows the unreality of some theoretical treatments of the liquid state. Diffusivity begins from the temperature at which V equals V(0) and can be correlated for temperature dependence, and for solute-solvent interrelations.  相似文献   

9.
棉花响应UV-B辐射的信号初探   总被引:1,自引:0,他引:1  
以3种棉花为供试材料,研究紫外线-B(UV-B)辐射及外源SNP、ABA叠加处理对棉花幼苗表观形态及内源H2O2与NO水平的影响。结果表明,UV-B辐射引起棉花幼苗叶片呈现锈色伤斑,离体叶片明显失水萎蔫。叶片外源涂抹SNP、ABA能减轻UV-B辐射引起的幼叶伤斑与萎蔫症状,缓解UV-B辐射所造成的伤害。DAB及DAF-2DA染色结果显示,UV-B辐射引起棉花内源H2O2与NO含量增加,而NO的释放通过减少H2O2积累减轻紫外辐射对棉花的伤害。ABA预处理可增强棉花对紫外伤害的耐受能力,且与H2O2与NO的释放密切相关。UV-B辐射对棉花生长造成伤害,H2O2、NO及ABA都参与棉花应答UV-B胁迫的信号转导过程。  相似文献   

10.
采用同位素示踪技术,研究了Cl对马铃薯的同化作用及吸收养分的影响。结果表明,培养液中Cl浓度过高会影响马铃薯对~(14)CO_2同化,减少对~(15)NO_5和H_2 ~(32)PO_4PO_4的吸收。  相似文献   

11.
[目的]测定6种杀虫剂对福建省稻纵卷叶螟田间种群的毒力及田间防治效果,为稻纵卷叶螟持续控制提供科学依据.[方法]采用浸叶法测定氯虫苯甲酰胺、乙基多杀菌素、茚虫威、阿维菌素、甲氨基阿维菌素和毒死蜱对福建省3个不同地理种群(福建福州、闽侯和沙县)稻纵卷叶螟3龄幼虫的室内毒力;在田间稻纵卷叶螟1~2龄幼虫高峰期,采用田间茎叶喷雾法开展氯虫苯甲酰胺、乙基多杀菌素、茚虫威、阿维菌素、甲氨基阿维菌素和毒死蜱等6种杀虫剂对稻纵卷叶螟的田间防治效果试验.[结果]室内毒力测定结果显示,3个地理种群稻纵卷叶螟对同一种杀虫剂的敏感性均以福州种群最敏感,其次是闽侯和沙县种群;6种供试杀虫剂对同一种群稻纵卷叶螟3龄幼虫的毒力排序为:阿维菌素>乙基多杀菌素>甲氨基阿维菌素>氯虫苯甲酰胺>茚虫威>毒死蜱.在试验设计剂量范围内,6种供试药剂对稻纵卷叶螟均具有良好的田间控制作用,药后14d的保叶效果为80.02%~88.81%,杀虫效果为82.99%~95.38%.[结论]福建省稻纵卷叶螟尚未对氯虫苯甲酰胺、乙基多杀菌素、茚虫威、阿维菌素、甲氨基阿维菌素和毒死蜱等6种杀虫剂产生明显的抗药性,6种药剂可有效控制稻纵卷叶螟的为害.  相似文献   

12.
高健  刘令峰 《安徽农业科学》1996,24(1):67-69,72
监测分析铜陵市降水的主要化学组成,结果表明SO2-4是降水中阴、阳离子量最高的离子,它是决定降水酸度的主导离子,NO-3对降水氢离子浓度也有一定影响,且铜陵市降水中NO-3的量高于一般酸雨区,阳离子中以Ca2+和NH+4的量居高。其中SO2-4来源于大气中的SO2,Ca2+来源于大气中的TSP,NO—3来源于大气中的NOx。各单种离子含量高低不能决定降水氢离子浓度,氢离子浓度大小只取决于降水中阴、阳离子平衡状况。电导率是反映降水污染程度的一种指标,实际操作中行之有效,较为便捷。  相似文献   

13.
[目的]为了从生化与分子水平上研究卫星搭载后辣椒突变后代的遗传变异性。[方法]对卫星搭载后的辣椒种子返地种植,经田间初步筛选,采集生长期顶端嫩叶,对SP1~SP4代进行蛋白质的SDS-PAGE电泳和RAPD检测分析。[结果]卫星搭载后辣椒叶片中的蛋白发生了变异,与对照有明显差异,SP2代起蛋白条带比对照增加了2条,分子量分别为15.0 kD和27.0 kD,且这种变异能够稳定遗传。RAPD分析表明,所用45个随机引物中有6个引物扩增出了条带,其中5个引物扩增出了特异条带。卫星搭载后的辣椒植株DNA突变程度为:S23=7.2%,S27=1.6%,S33=2.4%,S62=3.2%,S68=13.6%。突变后代在DNA水平上与对照存在差异,说明突变体基因发生了点突变或染色体互换、缺失。[结论]该研究对于辣椒空间育种具有重要的指导意义。  相似文献   

14.
在水温16~23℃、盐度30、pH8.0的环境条件下,采用静水试验法测定硫酸铜(CuSO4.5H2O)、硫酸锌(ZnSO4.7H2O)、氯化镉(CdCl2)和硝酸铅[Pb(NO3)2]4种重金属盐对泥东风螺Babylonia lutosa幼螺的急性毒性。结果显示,对泥东风螺幼螺24、48、72和96h的半数致死质量浓度(LC50),CuSO4.5H2O分别为2.596、1.037、0.690和0.400 mg.L-1;ZnSO4.7H2O分别为16.384、4.738、3.225和2.721mg.L-1;CdCl2分别为17.286、7.340、3.799和2.361 mg.L-1;Pb(NO3)2分别为650.640、410.595、262.342和141.525mg.L-1。CuSO4.5H2O、ZnSO4.7H2O、CdCl2和Pb(NO3)24种重金属盐对泥东风螺幼螺的安全浓度(SC)分别为0.040、0.272、0.236和14.153mg.L-1;Cu2+、Zn2+、Cd2+和Pb2+、4种重金属离子对泥东风螺幼螺的安全浓度分别为0.010、0.062、0.148和8.501mg.L-1,其毒性大小为Cu2+>Zn2+>Cd2+>Pb2+。  相似文献   

15.
A new approach is described for probing domains of ordered self-assemblies of amphiphilic monolayers at the aqueous solution interface. The method has potential importance for the study of membrane structure, Langmuir-Blodgett films, and nucleation processes of two-and three-dimensional crystals. Electron diffraction (ED) patterns indicative of two-dimensional crystalline self-assembly were obtained from samples, which were examined by cryo-electron microscopy, of monolayers of water-insoluble amphiphiles on vitrified aqueour substrates. The apparent hexagonal symmetry of an ED pattern from a C(16)H(33)OH monolayer was interpreted in terms of multiple twinning. Monolayers of the CL(31)H(63)OH and cadmium salt of C(19)H(39)CO(2)H that were studied by dark-field techniques displayed faceted two-dimensional crystallites with a maximal size of 1 to 2 micrometers. Epitaxial nucleation of hexagonal ice by the C(31)H(63)OH monolayer has also been demonstrated by ED.  相似文献   

16.
Acid precipitation: natural versus anthropogenic components   总被引:1,自引:0,他引:1  
The concentrations of H(+), SO(4)(2-), and NO(3)(-) in the precipitation of eastern North America are greater now than they were historically as a result of fossil-fuel combustion. Because of a lack of data prior to 1950, the absolute increases in the concentrations of these three ions are unknown. This problem can be addressed by comparing the composition of precipitation from areas sensitive to acidic deposition with that of precipitation from remote areas. An analysis of precipitation data indicates that many areas of eastern North America receive precipitation with substantially greater H(+), SO(4)(2-), and NO(3)(-) concentrations than remote areas. For example, SO(4)(2-), the most ecologically significant indicator of change, is enriched 2 to 16 times in eastern North American precipitation relative to its concentration in remote areas.  相似文献   

17.
马纯艳  徐昕  郝林  曹军 《中国农业科学》2007,40(11):2556-2562
 【目的】研究小白菜幼苗对二氧化氮(NO2)急性胁迫的应答及过氧化氢(H2O2)的调节作用。【方法】在自制的熏气箱中对供试植株进行NO2(浓度分别为0.25、0.5、1.0和2.0 μl•L-1)熏蒸24 h (10﹕00~次日10﹕00),测定某些生理生化指标。延长熏气至7 d,每天7 h (8﹕00~15﹕00),测定植株的生长速率。为了评价外源H2O2在植株对NO2应答中可能的调节作用,熏气前1 d对试验组叶面喷洒10 mmol•L-1 H2O2溶液(相当于每棵植株喷洒约1 mg H2O2),对照组喷洒等量蒸馏水。【结果】0.25 μl•L-1 NO2促进小白菜生长,而0.5 μl•L-1及以上浓度NO2使植株生长速率和叶绿素含量显著降低,叶片硝酸还原酶(NR)和超氧化物歧化酶(SOD)活性以及丙二醛(MDA)含量增加;1 μl•L-1及以上浓度NO2使老叶片出现坏死,绿色部分的过氧化氢酶(CAT)活性和硝酸盐(NO3-)含量增加,抗坏血酸(ASA)含量和光合速率下降,但气孔导度不受影响。10 mmol•L-1 H2O2预处理显著减轻NO2对植株的不利影响,其中生长速率、ASA和MDA含量等与只通入碳滤空气的对照水平相当,光合速率明显恢复,但NO3-含量和NR活性没有变化,SOD和CAT活性被进一步诱导,气孔导度降低。【结论】NO2急性胁迫引发了小白菜幼苗氧化胁迫伤害;H2O2预处理提高了小白菜的抗氧化能力,增强了对高浓度NO2的耐受性;NO2熏蒸使小白菜叶片NO3-含量增加。  相似文献   

18.
茶园生态系统的一氧化氮年排放特征   总被引:2,自引:1,他引:1  
采用静态暗箱-化学发光法,对亚热带典型茶园不同施肥处理(常规施尿素、施有机肥和不施肥对照)条件下的一氧化氮(NO)排放通量进行了原位周年观测。结果显示:施肥茶园的NO排放量主要集中在3—9月(春夏季)的茶树生长期,占全年排放量的58%~73%;土壤铵态氮含量是茶园在春夏季NO排放通量变化的主要环境控制因素;对照、尿素、有机肥处理的NO年排放量分别为2.85、19.42、17.04 kg N·hm-2,施肥显然大幅度增加了NO排放;与茶农常规施尿素处理相比,施有机肥处理显著降低了约12%的NO年排放量;在整个观测期内,常规施尿素和施有机肥处理的NO年直接排放系数分别为3.68%和3.15%。这些结果表明,我国亚热带茶园可能是一个不容忽视的NO强排放源,对此尚需多地点多年的长期研究进一步证实。  相似文献   

19.
不同营养液水培对卡特兰生长发育的影响   总被引:1,自引:0,他引:1  
陈曦  方正  李英丽  赵斌  苏頔 《安徽农业科学》2011,39(20):12029-12030
[目的]研究不同营养液配方对卡特兰(Cattleya hybrida)生长发育的影响。[方法]采用水培方法,以清水培养为对照。[结果]配方C[0.614 0 mg/L Ca(NO3).24H2O+0.283 0 mg/L KNO3+0.240 0 mg/LNH4NO3+0.136 0 mg/L KH2PO4+0.154 0 mg/LMgSO4.7H2O+0.022 0 mg/L K2SO4+0.017 0 mg/L K2HPO4+0.012 0 mg/L NaC l+31.194 0 mg/L Na2Fe-EDTA+2.863 0 mg/LH3BO3+2.1190 mg/LMnSO4.4H2O+0.230 0 mg/L ZnSO4.7H2O+0.074 9 mg/L CuSO4.5H2O+0.024 7 mg/L(NH4)6MO7O2.4H2O]所处理植株的各项形态指标均明显优于其他配方,叶绿素含量也高于其他配方,但丙二醛(MDA)的含量与其他配方相比差异不显著。[结论]该研究可为卡特兰的无土栽培提供科学依据。  相似文献   

20.
为探讨油橄榄叶提取物(OLE)对铅中毒小鼠大脑海马组织超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、一氧化氮合酶(NOS)活性及丙二醛(MDA)、一氧化氮(NO)含量的影响,选100只健康小鼠,每日灌胃醋酸铅溶液的同时灌胃不同剂量的OLE进行治疗,连续用药30d,检测海马组织SOD、CAT、NOS活性及MDA和NO含量的变化.结果表明:与模型对照组相比,小鼠灌胃OLE后海马组织SOD、CAT、NO、NOS水平均升高,MDA含量降低.说明油橄榄叶提取物对铅中毒小鼠有一定的疗效,能减轻铅中毒引起的海马脂质过氧化损伤,提高NOS、NO的水平.  相似文献   

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