焦亚硫酸钠对大鼠背根节神经元钾电流的影响

应用全细胞膜片钳技术,研究SO2体内衍生物和食品添加剂———焦亚硫酸钠(sodiummetabisulfite,SMB)对大鼠背根节(DRG)神经元瞬间外向钾电流(TOCs)和延迟整流钾电流(IK)的影响.结果表明,SMB可增大TOCs和IK,且具剂量依赖性和电压依赖性.10μmolL-1的SMB不影响TOCs的激活过程,给药前后TOCs的半数激活电压为(3.15±2.29)mV和(4.72±1.92)mV(N=8,P>0.05),不改变其斜率;但10μmolL-1的SMB却非常显著地影响TOCs的失活过程,给药前后其半数失活电压分别为(-53.6±0.45)mV和(-38.85±0.68)mV(N=8,P<0.01),也不改变其斜率.10μmolL-1的SMB显著提前IK的激活过程,给药前后IK的半数激活电压为(-11.98±3.50)mV和(-33.21±5.67)mV(N=8,P<0.01),不改变其斜率.SMB显著增大TOCs和IK,使IK的激活过程提前,抑制TOCs的失活过程,从而导致细胞内K 通过K 通道外流增加,进而可能对DRG神经元功能产生不利影响.图6参16     

有机磺酸类化合物的络合萃取研究

本文以三烷基胺为络合剂,正辛醇,煤油,氯仿,四氯化碳等为稀释剂,测定了络合萃取剂对于对甲基苯磺酸,磺基水杨酸稀溶液的相平衡分配系数,讨论了稀释剂,体系ＰＨ值和７３０１络合剂含量对萃取相平衡分配系数Ｄ值的影响,确定了形成的萃合物的组成。     

Environmental and genetic influences on mating strategies along a replicated food availability gradient in guppies (Poecilia reticulata)

Food availability is expected to influence the relative cost of different mating tactics, but little attention has been paid to this potential source of adaptive geographic variation in behavior. Associations between the frequency of different mating tactics and resource availability could arise because tactic use responds directly to food intake (phenotypic plasticity), because populations exposed to different average levels of food availability have diverged genetically in tactic use, or both. Different populations of guppies (Poecilia reticulata) in Trinidad experience different average levels of food availability. We combined field observations with laboratory “common garden” and diet experiments to examine how this environmental gradient has influenced the evolution of male mating tactics. Three independent components of variation in male behavior were found in the field: courtship versus foraging, dominance interactions, and interference competition versus searching for mates. Compared with low-food-availability sites, males at high-food-availability sites devoted more effort to interference competition. This difference disappeared in the common garden experiment, which suggests that it was caused by phenotypic plasticity and not genetic divergence. In the diet experiment, interference competition was more frequent and intense among males raised on the greater of two food levels, but this was only true for fish descended from sites with low food availability. Thus, the association between interference competition and food availability in the field can be attributed to a genetically variable norm of reaction. Genetically variable norms of reaction with respect to food intake were found for the other two behavioral components as well and are discussed in relation to the patterns observed in the field. Our results indicate that food availability gradients are an important, albeit complex, source of geographic variation in male mating strategies.     

Nutrients Can Enhance Phytoremediation of Copper-Polluted Soil by Indian Mustard

An orthogonally designed experiment was conducted to study the single and combined effects of N, P and K on phytoremediation of Cu-polluted soil by Indian mustard. Addition of fertilizer N and P significantly increased Indian mustard shoot yield. Two high treatments combined with N resulted in the highest yields, followed by low-P combined with N. In contrast, high P with no N gave no yield increase and K had no effect on yield of Indian mustard. Nitrogen and P increased the amount of chlorophyll in the leaves, indicating that the yield increases were due to enhanced photosynthesis. Nitrogen application had no effect on plant Cu concentrations but addition of P slightly decreased plant Cu concentrations, likely a dilution effect resulting from the increase in yield. Among the treatments, N and P applied at 100 and 200 mg kg^–1 respectively with no K application resulted in the highest Cu uptake. Thus, a combination of low N and high P produced a yield increase in Indian mustard that was more than adequate to compensate for a slight decrease in Cu concentration, resulting in the highest Cu removal from the contaminated soil.     

不同AM真菌对三叶草耐油性的影响

在盆栽条件下研究了4个油浓度（0、5000、10000和50000w/mgkg^-1）下接种辽河油田污染土壤中分离出的3种AM真菌（Glomus mosseae，G.geospora，G.constrictum）对三叶草耐油性的影响。试验结果表明：1）随着油浓度的增加，侵染率亦增加，10000mgkg^-1时G.geospora和G.constrictum的侵染率分别为67.65％和82.86％；2）从侵染率、地上部生物量和菌根依赖性来看，随着油浓度的增加，最适的AM真菌亦不一样，油浓度为0、5000和10000mgkg^-1时，最适AM真菌分别是G.geospora、G.mosseae和G.constrictum；3）油污染土壤上接种AM真菌能促进植株的地下部和地上部的生长，接菌处理的茎干重比相应的对照增加62.2％-267.1％；4）随着油浓度的增加和植物的生育进程，AM真菌的接种效应在增强。图3表3参14     

环戊酮和环己酮的微生物降解途径、相关酶和基因研究进展

简略介绍了环戊酮和环己酮的应用及危害,综述了目前国内外在环戊酮和环己酮微生物降解方面的研究进展.具体介绍了环戊酮和环己酮降解代谢的过程及其相关的酶类和编码这些酶的基因,重点阐述了环戊酮1,2-单加氧酶和环己酮1,2-单加氧酶及其编码基因.图4参19     

车用汽油铅损害及其对策研究

针对车用汽油的抗爆性能要求,探讨四乙基铅（Ｐｂ（Ｃ２Ｈ５）４）抗爆添加剂的作用机理,并着重分析研究了由此而引起的发动机铅排放对人类造成的损害及给大气环境等带来的污染。还探讨了车用汽油铅损害的对策及其最新进展     

铁改性赤泥吸附剂的制备及其除砷性能研究

以氧化铝生产废渣--赤泥为原料,采用铁盐改性处理制备了新型羟基铁包覆型赤泥除砷吸附剂.研究考察了吸附剂吸附砷效能、投加量、吸附时间和pH值对吸附除砷效果的影响;采用扫描电镜(SEM)、红外光谱(IR)、比表面积(BET)等仪器对吸附剂进行了表征,并探讨了吸附机制.结果表明,铁盐改性赤泥吸附剂对As(V)具有显著吸附效能,在pH为7,初始砷浓度为1 mg·L-1,铁盐改性赤泥吸附剂饱和吸附容量为50.6mg·g-1时,除砷率高达99.9%,吸附后出水砷含量可达到0.01 mg·L-1以下,吸附规律符合Langmuir等温方程式;溶液pH值显著影响砷去除效果,吸附机制主要为羟基铁的表面吸附机制;吸附后的吸附剂可通过NaOH溶液再生,脱附率达到92.1%.     

秸秆焚烧对玉溪市大气PM10的影响解析研究

以水溶性钾为示踪元素,解析秋收季节秸秆焚烧对玉溪市大气PM10的贡献.结果表明,2001年秋收季节(10月)水溶性钾浓度(7.68μg/m3)比夏季水溶性钾浓度(2.38μg/m3)高3.2倍,与7月至12月份PM10浓度变化呈显著相关,相关系数为0.810.很显然,秋收季节秸秆焚烧对玉溪市大气PM10有负面影响.     

高铁酸钾水处理剂的制备及稳定性研究

通过次氯酸盐氧化法制备高铁酸钾的工艺,探讨了次氯酸盐浓度、铁盐投加量、反应温度等对高铁酸钾纯度、产率的影响,研究发现当初始ClO-浓度为137.3g/L,除盐工序温度控制在10℃左右,铁盐投加量为化学计量的30%时,可得到纯度为96.4%、产率为45.3%的高铁酸钾固体.用XRD、FIRT和SEM对高铁酸钾进行了表征分析.初步研究了高铁酸钾母液中KOH、KCl、KNO3、Fe(NO3)3、KClO等杂质对高铁酸钾溶液稳定性的影响,结果表明碱度越高,高铁酸钾溶液稳定性越强, KCl、KNO3使高铁酸钾溶液稳定性略有降低, KClO对高铁酸钾溶液具有强稳定性,三价铁盐的存在能促进高铁酸钾溶液的快速分解.