甲胺磷农药降解菌的筛选鉴定及其降解效能研究

分别从黄冈棉田、荆州农田、沙市农药厂等长期受有机磷农药污染的不同环境土壤取样,通过富集培养,筛选分离到10株甲胺磷(MAP)降解菌.测定了各菌株的降解效能.选取降解效果较好的HS-A32菌株进行了初步研究.提取该菌总DNA进行16S rDNA PCR扩增、测序,BLAST检索及序列分析表明,HS-A32菌与不动杆菌的同源性为98%.结合生理生化实验结果,初步确定HS-A32菌为不动杆菌属(Acinetobacter).通过薄层色谱(TLC)及高效液相色谱(HPLC)对MAP降解进行了定性和定量分析.结果表明,该菌能以MAP作为唯一的碳源和氮源生长.接种该菌于500 mg/L的MAP无机盐液体培养基中,35℃、120 r/min振荡培养3 d,对甲胺磷降解率可达86%,是一株甲胺磷高效降解菌.     

某企业转炉氧枪修理车间工艺设计探讨

介绍了某企业转炉炼钢氧枪维修间的工艺、设备选型、车间布置和能源介质消耗等,并总结了该氧枪维修间工艺设计特点。     

弥散供氧流动特性及其富氧效果

研究了大空间局部圆形出氧口弥散供氧流动特性及其富氧效果.弥散供氧轴向最大速度和氧气轴向最大浓度均随轴向距离增加而衰减,且在轴向x=0~0.6 m范围内具有很大速度梯度和浓度梯度.不同出流速度下弥散形成的富氧区域形状是相似的,较小管径下富氧区域下游的浓度轮廓更接近“半椭圆”形,弥散范围更大;拟合得到富氧区域外边界扩展半宽度随轴向距离变化的关系式及富氧面积随出流流量变化的关系式.相同流量的富氧采用双出氧口弥散形成的富氧面积比单出氧口弥散形成的富氧面积减少约10%;相同流量的富氧以6 mm管径弥散形成的富氧面积比8 mm管径的富氧面积增加约10%.     

Therapeutical effect of Shengmaisan is determined by the interaction among the three herbs

Shengmaisan is a recipe of traditional Chinese medicine, which is composed of three herbs. The interaction among the components from the three herbs of Shengmaisan is investigated using FT-IR, Matrix Assistant Laser Desorption/Ionization Time of flight mass spectrometry (MALDI TOF MS) and TEM observation. Interactions among various components from different herbs cause enhancement of the solubility of some component and suppression of the solubility of others. Results from MALDI-TOF MS show that some components found in the decoction from a single herb disappear when different herbs are decocted together. On the other hand, new substances are produced when two and/or three herbs of Shengmaisan are decocted together. TEM showed that vacuoles formed in the decoction from two and/or three herbs of Shengmaisan but did not occur in any decoction from a single herb. This result provides us direct evidence that the solubilized structure is formed by the interaction among the components from different herbs. This knowledge helps us to understand the therapeutical effects of traditional Chinese medicine.     

活性氧消毒剂制备技术及空气消毒效果的研究

文中对活性氧消毒剂的制备工艺及其对于空气的消毒效果进行了阐述，说明其制造工艺是一种原子经济反应，新型的环境友好化工过程，对白色念球菌(Pseudomonasaeruginosa)、金黄色葡萄球菌 (Sylococcusccureus)的杀菌效果均高达99.90%，通过相关的试验数据说明消毒剂的性能稳定，无毒，对皮肤无刺激性。     

超声成像测井中图像“链条效应”的识别与修复研究

通过对超声成像测井过程中因测井仪器下放遇阻和上提遇卡而导致抖动,造成采样图像出现“链条效应”特征的详细分析,设计出针对此类病态图像的自动识别与修复算法;分别应用于典型实验数据与实际测井资料处理中,并进行效果比对_该算法为进一步改善成像资料图像质量提供了有效的解决方案．     

通过合金和去合金过程制备一种海绵状的纳米多孔铂以及对氧的电催化还原

采用一种简易的方法制备了海绵状的球形纳米多孔铂,首先是用循环伏安法在玻碳电极上电沉积得到铂铜合金,然后在浓硝酸中刻蚀合金去掉铜．用到场发射扫描电镜、X射线光电子能谱、X射线衍射和循环伏安法对其进行了表征．也对制备此种铂催化剂的条件进行了优化．此种铂修饰电极对氧的还原表现出很高的电催化活性,其氧的还原峰电流是相应纳米铂修饰电极的四倍．这种制备海绵状纳米多孔结构的方法以及所得到得到铂修饰电极可能在燃料电池和生物传感器等领域有着很大的应用前景．     

溶解氧和气泡对食蚊鱼生存的影响

为了观测溶解氧对鱼生存的影响,在250mL^3次脱气水中加不同深度的金属网对食蚊鱼的生存状况进行比较,在真空脱气水和未脱气水的液面覆盖培养皿或覆盖液体石蜡时食蚊鱼的生存状况进比较,发现鱼不适于在溶解氧和气泡都很少的3次真空脱气水中生存．通过对比还发现,在相同的环境条件下,雄食蚊鱼的生命力普遍强于雌食蚊鱼;同时在微扰实验中发现,微量鱼水中含有溶解氧、气泡以及吸附了气泡的微米级颗粒,这些气体足以维持3条鱼存活4h以上．利用真空脱气方法观察鱼类的极限生存条件可能会成为一种全新的研究方法．     

护理程序在精密件附着体义齿修复中应用的效果观察

目的 探讨护理程序在精密件附着体义齿修复牙列的意义.方法 针对口腔科患者对牙科恐惧的心理特征,采取一系列的心理护理措施,应用护理程序并配合四手操作技巧,减轻患者不适感,使结果更加完美.结果 在接诊时与患者交谈过程中,大概了解其心理担忧的问题,经过术前的心理疏导,治疗中充分运用四手操作技能来主动配合,操作技术娴熟,取得医、护、患间良好的合作,收到满意的修复效果.结论 四手操作能够保护患者、医生、护士的体力,节省患者张口的时间,减少患者的疲惫,增强患者的医从性,更好地提高工作效率,从而提高精密件附着体修复牙齿缺失的准确性和舒适性.     

氧电极催化剂的组成对H2O2分解活性的研究

以CuCl2和FeCl3原料，采用NaOH溶液中沉淀，并将沉淀物在空气中加热、氧化一还原、脱水的方法，制备不同Cu：Fe氧化物的催化荆(X=0．5、1．0、1．5、2．0、2．5、3．0)，分别以各催化剂在其他条件相同的情况下，催化分解H202，测定各反应的速率常数。并进行对比，以K对X作图表示活性与配比的关系。得出Cu，Fe3-xO4 Cu：Fe(X=2．5)时催化活性最高。     

Structure of the sulphiredoxin-peroxiredoxin complex reveals an essential repair embrace

Typical 2-Cys peroxiredoxins (Prxs) have an important role in regulating hydrogen peroxide-mediated cell signalling. In this process, Prxs can become inactivated through the hyperoxidation of an active site Cys residue to Cys sulphinic acid. The unique repair of this moiety by sulphiredoxin (Srx) restores peroxidase activity and terminates the signal. The hyperoxidized form of Prx exists as a stable decameric structure with each active site buried. Therefore, it is unclear how Srx can access the sulphinic acid moiety. Here we present the 2.6 A crystal structure of the human Srx-PrxI complex. This complex reveals the complete unfolding of the carboxy terminus of Prx, and its unexpected packing onto the backside of Srx away from the Srx active site. Binding studies and activity analyses of site-directed mutants at this interface show that the interaction is required for repair to occur. Moreover, rearrangements in the Prx active site lead to a juxtaposition of the Prx Gly-Gly-Leu-Gly and Srx ATP-binding motifs, providing a structural basis for the first step of the catalytic mechanism. The results also suggest that the observed interactions may represent a common mode for other proteins to bind to Prxs.     

Evolvability of an RNA virus is determined by its mutational neighbourhood

The ubiquity of mechanisms that generate genetic variation has spurred arguments that evolvability, the ability to generate adaptive variation, has itself evolved in response to natural selection. The high mutation rate of RNA viruses is postulated to be an adaptation for evolvability, but the paradox is that whereas some RNA viruses evolve at high rates, others are highly stable. Here we show that evolvability in the RNA bacteriophage phi6 is also determined by the accessibility of advantageous genotypes within the mutational neighbourhood (the set of mutants one or a few mutational steps away). We found that two phi6 populations that were derived from a single ancestral phage repeatedly evolved at different rates and toward different fitness maxima. Fitness measurements of individual phages showed that the fitness distribution of mutants differed between the two populations. Whereas population A, which evolved toward a higher maximum, had a distribution that contained many advantageous mutants, population B, which evolved toward a lower maximum, had a distribution that contained only deleterious mutants. We interpret these distributions to measure the fitness effects of genotypes that are mutationally available to the two populations. Thus, the evolvability of phi6 is constrained by the distribution of its mutational neighbours, despite the fact that this phage has the characteristic high mutation rate of RNA viruses.     

Grain size effect of IrO2 nanocatalysts for the oxygen evolution reaction

Combined with air annealing, rutile-structured IrO 2 nanoparticles with various sizes were prepared using colloidal method. The nanoparticles were used as the electrocatalysts for the oxygen evolution reaction (OER) in acidic media, and their grain size effect was studied. The results show that with the increase in annealing temperature, the grain size of the catalyst increases, and the voltammetric charges (the electroactive areas) and apparent activity for the OER decrease. The relationship between the intrinsic activity and the annealing temperature exhibits a volcano-type curve and the catalyst annealed at 550 ℃ achieved the best result.     

脱落酸对离体叶片衰老的影响及其与活性氧代谢的关系

研究了脱落酸对离体韭菜叶片衰老的影响与活性氧代谢的关系.发现在暗诱导衰老过程中膜脂过氧化产物丙二醛含量随超氧物歧化酶、过氧化氢酶活性和抗坏血酸、谷胱甘肽含量下降而增加.脱落酸处理后,伴随着叶绿素和蛋白质含量下降,超氧物歧化酶、过氧化氢酶活性和抗坏血酸、谷胱甘肽含量降低,而丙二醛含量增加.证明脱落酸促进离体韭菜叶片衰老的作用与活性氧代谢有密切关系.     

论会计诚信的缺失与重塑

分析了导致会计从业人员诚信缺失的原因，提出了一些重塑会计诚信道德的建议，以期根除会计诚信缺失的“毒瘤”。