新疆北疆寒冷地区非烧土坯墙体材料力学性能的研究

对新疆北疆纯粘土、粘土中掺入一定量水泥、石灰和粉煤灰制成的材料试件进行试验,测试试件在不同配合比下的抗压、抗折强度及导热系数。研究不同含水率,不同掺量石灰、水泥和粉煤灰对混合材料的抗压、抗折强度、导热系数的影响。得到适合于强度高、保温性能好的非烧土坯墙体材料。     

几种栽培基质的理化特性分析及其对香蕉幼苗生长的影响

[目的]了解不同栽培基质的理化性质,及其对香蕉幼苗生长的影响,为培育健康优质香蕉种苗提供理论基础.[方法]以椰糠、泥炭土及红壤土为基质原料,香蕉组培幼苗为植物材料,研究不同基质理化性质及其对幼苗生长的作用.[结果]椰糠和泥炭土都具有较小的容重,总孔隙度分别为82.6％和77.0％,持水孔隙度分别为59.2％和64.3％,使栽培介质具有较强的通透性和保水能力;而红壤土则有较大的容重,较差的通透性.椰糠有丰富有机质和较高全磷和全钾,而全氮则较低;红壤土的有机质和全氮含量远低于椰糠和泥炭土.椰糠处理的香蕉幼苗在株高、叶数、叶面积、干物重等方面具有较强的生长优势,泥炭土次之,而红壤土则表现最弱.根系形态参数表明,椰糠处理下植株根系较长、粗壮,根表面积较大,显著优于其他两个处理.[结论]单纯红壤土或泥炭土作为基质不能为香蕉幼苗提供最优的生长条件;椰糠具有更适于香蕉幼苗生长的理化性质,利于培育强壮健康无菌种苗,可作为重要的无土栽培介质而广泛应用.     

天津蓟州独乐寺古建筑群昆虫多样性及关键害虫防治

对天津蓟州区独乐寺古建筑群昆虫多样性进行系统调查,并对危害建筑、设施、重要文物和古树的害虫进行了综合防治研究。结果表明,寺内发生的昆虫共计12目37科66种,其中有害昆虫5目10科17种。危害古建筑木质构件和泥塑雕像等文物的主要是花斑皮蠹(Trogoderma variabile),危害古建筑室外木构件的主要为黑颚条蜂(Anthophora melanognatha)和黄胸木蜂(Xylocopa appendiculata),黑颚条蜂及十二斑毛斑蜂(Melecta duodecimmaculata)也在壁画和泥塑上筑巢危害;危害古树的主要为白蜡脊虎天牛(Xylotrechus rufilius)等害虫。另外,山斑大头泥蜂(Philanthus triangulum)在山门等处掘土筑巢,造成的危害比较严重。在相关害虫发生期、危害部位和习性调查基础上,综合采用色板、黑光灯、糖醋液诱杀和药物喷洒、注杆、滴孔、药棉填塞、熏蒸等方法,对各类害虫进行了防治,取得良好效果。     

Effect of Application Method on the Efficiency of Potassium Chloride in Wetland Rice on a Beidellitic Potassium Problem Soil

A greenhouse pot experiment evaluated the effect of incorporation and placement on the efficiency of KC1 in wetland rice on a K-problem soil with beidellitic clay mineralogy and high tendency to fix added K.
Placement turned out to be superior to incorporation by increasing significantly both grain and straw yields.

Zusammenfassung

Einfluß der Anwendungsmethode auf die Effizienz von Kaliumchlorid in Wasserreis auf einem beidellitischen Kali-Problem-Boden
In einem Gewächshaus-Gefäßexperiment wurde der Einfluß des Einmischens und der Plazierung auf die Effizienz von KC1 bei Naßreis in einem K-Problemboden mit beidel-litischem Ton, der eine starke Tendenz zur Fixierung von gedüngtem Kalium aufwies, untersucht. Die Plazierung erwies sich gegenüber einer Einmischung überlegen; dies galt signifikant sowohl für Korn- als auch Stroherträge.     

A total-continuous portal vein fistula in gastrointestinal and toxicology research

A method for the total collection of portal vein blood over extended periods has been developed. The method has been applied in gastrointestinal toxicology research involving rats. The method facilitated quantitative recovery of portal vein blood for 120 min for measurement and identification of absorbed radiolabeled components derived from a toxic lipphilic pesticide placed in the lumen of the small intestine. The method can be applied to any substance—nutrient, anutrient, xenobiotic chemical, or endocrine factor—absorbed into the portal vein from the gastrointestinal tract. The method (a) provides for collection of compounds absorbed from the gastrointestinal tract before distribution to nondigestive tissues (i.e., liver), (b) allows measurement of the compounds absorbed without the need to monitor flow rate, and (c) facilitates accumulation of sufficient material from the total portal circulation for analyses when submicrogram quantities are absorbed. The latter two features are important but impossible to attain with small samples of portal blood and are crucial in research with minute quantities of substrate. These features become requirements in metabolism and toxicology research. The method involves replacement of the portal blood with a suspension of perfluorohydrocarbons to substitute for the major functions of natural blood. The total-continuous portal vein fistula makes it possible to investigate metabolic and transport phenomena in live animals which previously could be explored only by in vitro methods. The method may be applied to conscious animals with further refinements.     

水分非饱和条件下土壤矿物界面有毒有机物转化机制研究进展

土壤矿物作为土壤重要活性组分，可驱动土壤有毒有机物化学转化，降低污染风险。以往土壤矿物与有毒有机物界面行为研究主要集中于水环境或矿物悬浊液体系，然而实际环境中土壤及其矿物常处于干燥、湿润等水分非饱和状态。近年来，水分非饱和条件下土壤矿物界面有毒有机物转化及机制已成为研究热点，相关研究获得一系列新发现。低含水量铁锰矿物、黏土矿物和金属离子饱和黏土矿物能驱动多环芳烃、抗生素等疏水性有毒有机物化学转化。水分非饱和环境会减弱矿物界面水分子与有毒有机物竞争活性位点，并使矿物发生脱水、向高活性结构转变。此外，土壤矿物水分状态也会影响有毒有机物转化产物，水分非饱和环境更有利于持久性自由基和卤代二噁英等中间产物的形成和稳定。以往研究认为，电子转移反应是土壤矿物界面有毒有机物转化机制，随着检测技术与理论计算的发展，自由基催化和水解作用机制逐渐被发现，相关机制研究精准至矿物晶型和晶面层面。虽然水分非饱和条件下土壤矿物界面有毒有机物转化及机制已逐渐清晰，但其研究广度和深度有待进一步拓宽和加深。建议未来在实际水分非饱和土壤和矿物中开展有毒有机物转化研究，深入探究还原转化过程，研发原位反应装置及检测方法，尝试从微纳米尺度和分子水平解析有毒有机物在矿物界面转化机制。     

水产养殖对甘肃盐碱区盐碱迁移的影响

为了探讨“以渔治碱”模式在盐碱地治理方面的成效及其作用机制,以甘肃省景泰县盐碱地为试验区,采用水产养殖治碱技术比较了砂型土壤和壤性土壤的治碱效果。通过定期监测和分析养鱼前后不同类型土壤和水体中水质参数的变化,研究水产养殖对该地区盐碱迁移的影响。结果表明,采用水产养殖模式在一定程度上可改良盐碱区的土壤环境,沙型土壤的盐碱治理效果优于壤性土壤,养殖期间产生的氨氮也并未呈现出一直升高的趋势,未对当地造成二次污染。本研究结果为“以渔治碱”模式在西北地区的应用和推广提供一定的理论依据及技术支撑。     

D33T214型重介质旋流器结构特点及在钱家营矿选煤厂应用分析

本文主要介绍了美国生产的克莱博斯D33T214型重介质旋流器的结构特点，以及该型旋流器在钱家营矿洗煤厂的使用情况。     

高产海岛棉田土壤微生物学特性研究

用混菌平板法和稀释频度法 ( MPN)对中壤土高产海岛棉田中的细菌、真菌、放线菌的数量与分布进行了测定。结果表明 ,细菌是中壤土海岛棉田微生物生命活动的最主要参与者。棉田三类土壤微生物呈现明显的季节变化。 0～ 2 0 cm的土层是微生物集中分布和生物学活性最大区域。氮素生理群中氨化细菌最多 ,芽孢细菌次之 ,硝化细菌再次之 ,好气性固氮菌最少     

Influence of soil pH and application of zinc on the yield and uptake of selected nutrient elements by rice

Abstract

Rice grown on a recently water‐leveled Crowley silt loam that contained less than 1.8 μg g^‐1 of 0.1 N HCl‐extractable Zn with pH levels ranging from 6.8 to 7.7, responded to Zn application. Each kg ha of applied Zn as Zn chelate, 14.2 % Zn, resulted in increases of +673, +477, and +2026 kg rice ha^‐1 at pH 6.8, 7.3, and 7.7, respectively. There was a critically low concentration of Zn in rice plants at the midtillering, first joint, and panicle differentiation stages of plant development when no Zn was applied. A yield response to applied Zn was obtained when the concentration of Zn in rice tissue was less than 15 μg g^‐1.

Application of Zn resulted in a significant increase in the uptake of N by rice plants at each of the three stages of plant development. Application of Zn also resulted in relatively large and significant increases in the uptake of Zn from the soil irrespective of soil pH. The uptake of Zn by rice plants at each of the growth stages showed a two‐ to three‐fold increase following Zn application when soil pH was 6.8 and 7.3. Also, the uptake of Zn by rice plants following Zn application showed a four‐fold increase at midtillering, a five‐fold increase at first joint, and a six‐fold increase at panicle differentiation, respectively, when soil pH was 7.7.