微生物降解三氟甲苯的研究

从含氟有机物污染的污泥中分离出5株优势菌株。对5株菌株进行生物忍耐力和生物降解试验。结果表明，这些菌株在驯化之后对有毒底物有较强的的忍受能力，在有毒底物浓度为1000mg／L时仍然能生长。在15d内，菌株Z1、Z2、Z3、Z4对三氟甲苯的降解率分别可达到100％、98．55％、97．02％、98．07％，初步探讨了三氟甲苯生物降解的路径。     

Strain analysis in Jurassic argillites of the Monte Sirino area (Lagonegro Zone, southern Apennines, Italy) and implications for deformation paths in pelitic rocks

Analysis of strain in Jurassic argillites forming part of the folded and thrusted sedimentary succession of the Lagonegro basin (southern Italian Apennines) has been carried out using ellipsoid-shaped 'reduction' spots as strain markers. Most of the determined finite strain ellipsoids are of oblate type and show a peculiar distribution of the maximum extension direction ( X), with maxima either subparallel or subperpendicular to the local fold axes. Using the strain matrix method, two different deformation histories have been considered to assist the interpretation of the observed finite strain pattern. A first deformation history involved vertical compaction followed by horizontal shortening (occurring by a combination of true tectonic strain and volume loss), whereby all strain is coaxial and there is no change in the intermediate axis of the strain ellipsoid. By this type of deformation sequence, which produces a deformation path where total strain moves from the oblate to the prolate strain field and back to the oblate field, prolate strain ellipsoids can be generated and may be recorded where tectonic deformation has not been large enough to reverse pre-tectonic compaction. This type of deformation history may be of local importance within the study area (i.e. it may characterize some fold hinge regions) and, more generally, is probably of limited occurrence in deformed pelitic rocks. A second deformation sequence considered the superposition of pre-tectonic compaction and tectonic strain consisting of initial layer-parallel shortening followed by layer-parallel shear (related to flexural folding). Also in this instance, volume change during tectonic deformation and tectonic plane strain have been assumed. For geologically reasonable amounts of volume loss due to compaction and of initial layer-parallel shortening, this type of deformation history is capable of producing a deformation path entirely lying within the oblate strain field, but still characterized by a changeover, during deformation, of the maximum extension axis ( X) from a position parallel to the fold axis to one perpendicular to it. This type of deformation sequence may explain the main strain features observed in the study area, where most of the measured finite strain ellipsoids, determined from the limb regions of flexural folds, display an oblate shape, irrespective of the orientation of their maximum extension direction ( X) with respect to the local structural trends. More generally, this type of deformation history provides a mechanism to account for the predominance of oblate strains in deformed pelitic rocks. Key words Finite strain states · Compaction · Tectonic strain · Deformation gradient tensors · Deformation paths     

苯丙氨酸解氨酶的分子生物学研究进展

苯丙氨酸解氨酶 (Ｐｈｅｎｙｌａｌａｎｉｎｅａｍｍｏｎｉａｌｙａｓｅ ,ＰＡＬＥ .Ｃ .4.3 .1.5 )是一种只存在于植物及微生物细胞内的酶 ,主要分布于高等植物如小麦、大豆、玉米、土豆及酵母[1] 、真菌[2 ] 、链霉菌[3]中 .在 ｐＨ 8.8时 ,ＰＡＬ催化苯丙氨酸脱氨生成肉桂酸和氨 ,当过量的氨存在 ,如 ｐＨ 10时 ,ＰＡＬ催化肉桂酸和氨 ,氨化加成生成Ｌ 苯丙氨酸 (Ｌ ｐｈｅｎｙｌａｌａｎｉｎｅ) .利用ＰＡＬ这种逆向催化特性转化肉桂酸生产Ｌ Ｐｈｅ ,已在国内外投入商业规模开发 ,成为当前生物化工领域研究与开发的热点 .Ｌ Ｐｈｅ是人…     

硝基苯降解菌在厌氧序批式反应器中处理硝基苯废水的应用

通过接种硝基苯降解菌于厌氧序批式反应器（ASBR），研究静态试验条件下和厌氧序批式工艺对硝基苯的降解规律，研究表明，应用生物强化技术处理硝基苯废水，具有很高的处理效率。     

直链烷基苯磺酸钠(LAS)降解菌的分离鉴定及其降解特性

从天津市某洗涤剂生产厂的排水沟污泥中分离到一株对直链烷基苯磺酸钠（LAS）具有较强降解能力的菌株LAS1，经生理、生化、VITEK微生物自动鉴定仪以及分子生物学等方法鉴定，该菌为放射形土壤杆菌（Agrobacter radiobacter），LAS1生长的最佳pH值为7．0，最适生长温度为30℃，无机氮可以促进其对LAS的降解，而有机氮则会对其降解LAS产生强烈竞争．当LAS浓度高于60mg／L时，LAS1的LAS降解能力受到一定程度的抑制．LAS1对LAS的降解时间动力学曲线为二级动力学反应．图4参5     

抗真菌多肽——捷安肽素高产菌的选育

从新疆棉株上分离得到一株细菌ZK ,经培养物性状和生理生化鉴定 ,确定该菌为芽孢杆菌属 (Bacillussp.)菌 ,其代谢产物为一种抗病原真菌的肽类物质———捷安肽素 .以此株菌作为出发菌株 ,进行紫外线、微波和亚硝基胍诱变 ,诱变处理后获得高产突变株Mv2 8,在摇瓶试验中 ,该变异株产捷安肽素活性比出发菌株提高 31.6 % .图 5表 5参 12     

青蒿无性系中青蒿素生物合成的相关因素

通过诱导丛生芽的方法得到青蒿高产无性克隆系S1,并用S1进行了青蒿素生物合成相关因素的研究 .发现在Hoagland培养液中添加 0 .4 4mg/L浓度的ZnSO4或者 5 .72mg/L的HBO3 时 ,能有效提高青蒿素的含量 .研究表明 ,青蒿素含量和青蒿各株系间的遗传差异存在很大关系 ,RAPD分析的结果表明 ,用OPA15能够在青蒿高产株系中扩增到OPA15 10 0 0 这一特异性片段 .另外 ,对青蒿素含量和青蒿生殖生长关系的研究表明 ,青蒿素含量最高的发育时期是现蕾期 .图 7表 1参 19     

冷挤压组合凹模的寿命估算

冷挤压组合凹模的失效主要是凹模内腔疲劳裂纹的出现,在模具设计的前期较为准确的估算出组合凹模的疲劳寿命是模具优化设计的前提。通过对组合凹模的应力分析后,采用Mises屈服准则的方法把凹模所受的多轴应力转化成单轴应力,再利用局部应力应变法找到了估算冷挤压组合凹模寿命的途径。     

驯化筛选微生物对油制气废水的降解特性

从5个菌源分离到的16株菌中筛选出S－2、Y－3和XH－3为优势菌种,分别用它们及其混合菌M－3研究对油制气废水的降解,60h之后CODcr的去除率为38．4％－44．0％,酚类化合物的去除率为95．4％－97．0％,芳烃类化合物的去除率为47．1％－53．7％,但氨氮的去除率只有14．0％－17．6％。采用GC／MS分析了处理前后废水中的芳烃类化合物,所筛选的微生物对芳环数≤3的芳烃类化合物降解能力强,还可去除一定量芳环数为4－6的芳烃类化合物。加入共代谢基质葡萄糖,可使CODcr、氨氮及可萃取有机物的去除率分别提高13．1％－22．9％、18．4％－22．7％及13．1％－18．1％;加入乙醇,可使CODcr、氨氮及可萃取有机物的去除率分别提高12．5％－21．2％、29．7％－42．2％及6．7％－7．7％。废水中芳烃类化合物的总去除率分别比无葡萄糖和无乙醇时提高了17．7％－21．7％和15．4％－21．2％。所筛选驯化的菌种有效地提高了油制气废水的降解效率。     

低应变反射波法基桩动测资料分析中的若干问题探讨

本文对低应变反射波法基桩动测资料分析中存在的信号分析方法、尺寸效应、桩周土的影响等问题的最新研究进展进行了分析,并且对相应问题给出了一些建议和可能的解决方法.