人工固沙植被区土壤酶活性研究

[目的]研究人工固沙植被区土壤酶的活性.[方法]通过采集流沙,自然植被区,1956、1964、1981、1987、1990年人工固沙植被的土壤表层样品(0-5 cm),对各类型土壤的脲酶、蔗糖酶、磷酸酶、纤维素酶、多酚氧化酶、淀粉酶、过氧化氢酶活性进行了研究.[结果]不同固沙年代土壤表层(0-5 cm)酶活性大小依次为自然植被区>1956年人工植被区>1964年人工植被区>1981年人工植被区>1987年人工植被区>流沙区;同一年代回沙植被区,不同地形之间土壤表层(0-5 cm)酶活性大小依次为迎风坡>背风坡.[结论]该研究结果为提高人工植被固定沙丘工程系统的稳定性提供了依据.     

漂浮育苗方式下烟草根茬腐解液对幼苗生长的化感效应

[目的]揭示烟草连作障碍的作用机制,为消除农业生产上烟草的连作障碍提供理论依据.[方法]以漂浮育苗的方式,研究了不同浓度烟草根茬腐解液对幼苗生长的影响.[结果]当烟草根茬腐解液浓度为0.1 g/ml时,能促进幼苗的生长,能显著提高烟株的干物质重量,增强硝酸还原酶活性和根系活力.随着腐解液浓度的提高,促进作用逐渐转为抑制作用.当烟草根茬腐解液浓度达0.2 g/ml时,烟株硝酸还原酶活性明显下降,过氧化物酶活性和丙二醛含量显著上升.当烟草根茬腐解液浓度达0.3 g/ml以上时,烟株硝酸还原酶活性最低,过氧化物酶活性和丙二醛含量达最大.[结论]烟草根茬腐解液对烟苗的生长产生了不同程度的化感效应,随腐解液浓度的提高表现出明显的"低促高抑"的现象.     

钨矿区砷污染与土壤微生物及酶活性相关性研究

通过野外采样及室内分析,研究赣南钨矿区的砷污染状况,土壤砷含量和形态对土壤微生物群落以及土壤酶活性的影响．结果表明:钨矿区土壤中砷全量及有效量均显著高于非矿区土壤,矿区土壤中砷以铁锰氧化物结合态为主,生物可给性强的可交换态砷占9.8 %~12 %,尾矿砂中砷以残渣态为主（39.7 %）,交换态砷占16.6 %.矿区土壤砷总量、可利用态砷对矿区土壤微生物数量的影响也呈现负相关,微生物类群对矿区污染的敏感性大小表现为:细菌＞放线菌＞真菌.矿区土壤脲酶、过氧化氢酶、蔗糖酶活性均受到砷污染的抑制,通过相关性分析得出,脲酶活性可以较好的指示钨矿区土壤砷污染程度.钨矿区土壤中微生物区系组成数量及土壤酶活性在一定程度上可反映该矿区砷污染特征.      

复合垂直流人工湿地脲酶和磷酸酶活性与黑臭河水净化效果

[目的]研究复合垂直流人工湿地脲酶和磷酸酶活性与黑臭河水的净化效果.[方法]以蜂巢石和软性填料为基质,通过构建生物栅复合垂直流人工湿地系统强化处理黑臭河水,并测定人工湿地不同功能区中2种填料的脲酶和磷酸酶活性,研究2种填料在不同功能区的挂膜性能.[结果]软性填料生物膜上的脲酶和磷酸酶活性显著高于蜂巢石填料生物膜上的活性,说明选择软性填料更利于生物膜的生长;脲酶活性与总氮的去除率显著相关,而磷酸酶活性与总磷的去除率相关性不显著.[结论]该研究结果为利用脲酶和磷酸酶活性作为评价黑臭河水净化效果和挑选合适的填料提供了依据.     

草地早熟禾根系生物量分布动态

[目的]研究秋季生长季中草地早熟禾根系生物量、根重密度、根长密度的分布动态.[方法]采用土钻法在生长季内对草地早熟禾草坪取样,研究根系生物量、根重密度、根长密度在时间、空间上的动态变化,以及生物量与土壤含水率的关系.[结果]在秋季生长季中,草地早熟禾根系生物量、根重密度、根长密度的变化规律相同,8月底达到峰值,分别为0.18 g/cm2、5.75×10-3 g/cm3和114.64cm/cm3.根系各指标的空间分布规律相同,随着土壤深度的增加,呈逐渐减少趋势.生物量与土壤含水率的变化趋势相同,说明草坪草在不同土壤水分条件下对根系分配不同的光合产物.[结论]该研究为认识根系周转规律,C、N在城市生态系统中循环、再分配的过程及根系不同时期的吸收策略提供理论基础.     

2种水葫芦-微生物系统水质净化效果的比较

[目的]研究无锡本地水葫芦和云南紫根水葫芦的水质净化效果.[方法]采用10种分离培养基分析2种水葫芦根际微生物的分布和数量,并通过监测水葫芦生物性状及水质指标,分析比较无锡水葫芦和云南紫根水葫芦的水质净化效果.[结果]水体中自然存在的微生物、浮游动物等对COD、氨氮、总磷具有一定的降解能力,种养水葫芦能进一步增强总氮、COD、总磷的降解,且无锡水葫芦对总氮降解能力好于紫根水葫芦,紫根水葫芦时COD、总磷的降解能力较强;无锡水葫芦生物量明显大于紫根水葫芦,无锡水葫芦生物量的增加是由叶柄增重引起的,而紫根水葫芦是由根系增重引起的.2种水葫芦老根的根际放线菌数量差异不明显著,新根的大多根际微生物数量差异明显.[结论]云南紫根水葫芦净化水质的能力强于无锡本地水葫芦,为利用水葫芦修复富营养化水体提供了理论依据.     

东乡普通野生稻根际微生物群落特征研究

[目的]研究东乡普通野生稻(Oryza rifipogon Griff.)根际微生物群落特征.[方法]采用氯仿熏蒸浸提法测定根系微生物生物量碳、氮;采用平板稀释培养法测定群落组成;采用最大或然计数法测定微生物生理群.[结果]东乡野生稻根际微生物生物量碳、氮平均值分别为83.02和16.98mg/kg(土),较普通栽培稻低;根际可培养微生物中细菌>放线菌>真菌;氮素生理群中氨化细菌>好氧固氮菌>反硝化细菌>嫌气性固氮菌>硝化细菌>亚硝化细菌.[结论]东乡野生稻根际微生物群落组成与普通栽培稻相比有差异.     

公路交通对水稻土壤微生物种群和数量的影响

[目的]探索农村公路交通污染对水稻土壤的影响程度.[方法]以距离公路10、50、200 m的盆栽水稻为研究对象,探讨公路交通污染对水稻土壤微生物种群和数量的影响.[结果]拔节期:在0～10 cm的土壤中,距离公路10和50 m的微生物数量明显少于距离公路200 m的.灌浆期:3个点的不同土层中土壤微生物数量明显高于拔节期,且在距离公路50 m的0～10 cm土层中微生物的数量对比拔节期明显上升.成熟期:0～10 cm土层中,相比灌浆期,距离公路10m的微生物数量有所提升,距离公路50m的有所下降;10～20 cm土层中,微生物数量比灌浆期有所上升.而在距离公路200 m的各个土层中的微生物数量受交通污染影响不明显.[结论]从土壤的不同深度来看,交通污染对土壤表层微生物生长有一定的抑制作用,且随着时间的延长,交通污染物逐渐向土壤深处迁移,开始对内层土壤微生物的生长产生影响;从离公路的不同距离来看,距离公路50、10、200 m的试验点受交通污染影响依次减小.     

磷矿废弃地对环境的影响及自我修复

通过不同年限的野外调查和土壤理化特性的分析,揭示了随着时间的演替变化、磷矿废弃地植被的群落结构和生物多样性、土壤肥力、土壤酶活性的变化规律.结果显示,随磷矿废弃地时间的演替,磷矿废弃地植被群落结构相对丰富,均匀度增大,生物多样性提高;酸性磷酸酶、脲酶随着磷矿废弃地时间的演替,上下层含量相对于对照都有所增加;而过氧化氢酶却随着磷矿废弃地时间的演替减小.     

长期滴灌施肥对荔枝根系生长及土壤pH的影响

[目的]探讨长期滴灌施肥汁荔枝(Litchi chinens)根系生长分布及荔枝园不同土层土壤pH变化的影响.[方法]采用田间试验,追肥包括CO(NH2)2、KCI和MgsO4 等,均通过滴灌施肥系统施入,主要施肥时期为每年荔枝的秋梢期、花期和结果期前后;过磷酸钙、花生麸及鸡龚等则以基肥的形式沿树冠滴水线沟施.[结果]滴灌施肥能显著促进荔枝根系的生长,增加根系与土壤的接触面积,连续6年滴灌施肥后滴灌施肥区土体中的根干重、根长、根表面积分别为非滴灌区的2.29、2.17和2.25倍.荔枝根系主要分布在0～40 cm土层,但滴灌施肥区和非滴灌区在0～20和20～40 cm土层中的根系分布存在明显的差异性,滴灌施肥更有利于根系向土壤深层生长分布.长期滴灌施肥条件下,荔枝园土壤酸化明显,与非滴灌区相比,滴灌施肥区在10～20 cm土层土壤pH的降幅最大,达到1.47个单位.[结论]该研究可为滴灌施肥技术在荔枝生产中的推广应用提供理论依据.     

转炉炉壳热应力分析

根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。     

焦炭热性能指标意义浅析

通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。     

Results of treatment of cancer of the cardia

Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of antibiotics of chemotaxis of human leukocytes

The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed.     

Quality of life of relatives of mental patients

Usage of quality of life of psychiatric patients' relatives as the parameter of estimation of the quality of psychiatric care is considered. By means of standard questionnaire elaborated by the authors as well as by means of both individual and group conversations the quality of life was analyzed in 40 relatives which lived together with psychiatric patients. Different spheres of their life and difficulties (financial, social-psychologic, production) were examined in families with such patients. The defects of psychiatric care that had direct influence on the quality of life of the psychiatric patients' relatives are outlined.