Adsorption equilibria for oxygen and nitrogen gas mixtures on 5a molecular sieves

Equilibria data for the adsorption of oxygen, nitrogen and binary mixtures of these gases are determined on 5A molecular sieve pellets. Pure component isotherms are presented at pressures up to 9 bar and at 278.15, 293.15 and 303.15 K. The binary equilibria are presented at the same temperatures and at pressures of 1.7 and 4.4bar. The binary data have been examined against values predicted by various models using regression parameters obtained from the pure component isotherms. For these systems the ideal adsorbed solution theory, Cook and Basmadjian model and the statistical thermodynamic model gave the best representation of the experimental data.     

Sensitivity of surface roughness parameters to changes in the density of scanning points in multi-scale AFM studies. Application to a biomaterial surface

In the field of biomaterials surfaces, the ability of the atomic force microscope (AFM) to access the surface structure at unprecedented spatial (vertical and lateral) resolution, is helping in a better understanding on how topography affects the overall interaction of biological cells with the material surface. Since cells in a wide range of sizes are in contact with the biomaterial surface, a quantification of the surface structure in such a wide range of dimensional scales is needed. With the advent of the AFM, this can be routinely done in the lab. In this work, we show that even when it is clear that such a scale-dependent study is needed, AFM maps of the biomaterial surface taken at different scanning lengths are not completely consistent when they are taken at the same scanning resolution, as it is usually done: AFM images of different scanning areas have different point-to-point physical distances. We show that this effect influences the quantification of the average (R(a)) and rms (R(q)) roughness parameters determined at different length scales. This is the first time this inconsistency is reported and should be taken into account when roughness is measured in this way. Since differences will be in general in the range of nanometres, this is especially interesting for those processes involving the interaction of the biomaterial surface with small biocolloids as bacteria, while this effect should not represent any problems for larger animal cells.     

An Estimate for the Entropy of Hamiltonian Flows

In this paper, we present a generalization to Hamiltonian flows on symplectic manifolds of the estimate proved by Ballmann and Wojtkovski in [4] for the dynamical entropy of the geodesic flow on a compact Riemannian manifold of nonpositive sectional curvature. Given such a Riemannian manifold M, Ballmann and Wojtkovski proved that the dynamical entropy h _μ of the geodesic flow on M satisfies the inequalitywhere v is a unit vector in T _p M if p is a point in M, SM is the unit tangent bundle on M, K(v) is defined as , where is the Riemannian curvature of M, and μ is the normalized Liouville measure on SM. We consider a symplectic manifold M of dimension 2n, and a compact submanifold N of M, given by the regular level set of a Hamiltonian function on M; moreover, we consider a smooth Lagrangian distribution on N, and we assume that the reduced curvature of the Hamiltonian vector field with respect to the distribution is non-positive. Then we prove that under these assumptions, the dynamical entropy h _μ of the Hamiltonian flow with respect to the normalized Liouville measure on N satisfies      

Dynamic modeling and simulation of absorption of carbon dioxide into seawater

In order to elucidate the dynamic performance of the CO₂ ocean disposal process, effects of operating parameters, such as gas flow rate, salinity and temperature, on the absorption of CO₂ into seawater were examined. The rate-based model consisting of the rates of chemical reaction and gas-liquid mass transfer was developed for simulating dynamic process of CO₂ ocean disposal. In modeling, non-ideal mixing characteristics in the gas and liquid phases are described using a tanks-in-series model with backflow. Experiments were performed to verify dynamic CO₂ absorption prediction capability of the proposed model in a cylindrical bubble column. The operation was batch and continuous with respect to liquid phase and gas phase, respectively. Experimental results indicate that the CO₂ gas injection rate increased the absorption rate but the increase in salinity concentration caused inhibition of the absorption of CO₂. The proposed model could describe the present experimental results for the dynamic changes and the steady-state values of dissolved CO₂ concentration and hydrogen ion concentration. The proposed model might effectively handle the prediction of the absorption of CO₂ into seawater in the CO₂ ocean disposal.     

阴离子捕收剂LKY试验室试验及工业试验研究

本文以阴离子捕收剂LKY试验室试验及工业试验的结果并与RA-315对比，表明LKY阴离子捕收剂的性能和选别效果都优于RA-315，完全可能取代RA-315药剂。为选矿药剂的开发提供了前景。     

美军炮位侦校雷达新进展

详细介绍美军炮位侦察雷达的改进情况以及新型炮位侦察雷达的研制情况。     

The sequence of 55 kb on the left arm of yeast chromosome XVI identifies a small nuclear RNA,a new putative protein kinase and two new putative regulators

We have sequenced and analysed a 55 786 bp fragment located on the left arm of chromosome XVI of Saccharomyces cerevisiae. The sequence contains 29 non-overlapping open reading frames (ORFs) longer than 300 bp, among which 12 genes have previously been sequenced: OYE3, REV3, SVS1, BEM4, CDC60, KIP2, PEP4, SPK1, PAL1, KES1, SNR17B and RPL37A. Three new ORFs, P2591, P2594 and P2597 are highly homologous to the human phosphotyrosyl phosphatase activator PTPA, to the pleiotropic regulator PRL1 of PP1 and PP2a protein phosphatases in plants and to the protein kinase PAR-1 in Caenorhabditis elegans, respectively. Three other ORFs, P2545, P2567 and P2578 have significant homology with ORFs of unknown function located on yeast chromosomes VIII, XVI and IV respectively. The sequences in nucleotides and in amino acids have been deposited in the EMBL data library under the Accession Number X96770.     

侧钻超短半径水平井J37-26-P14井钻井设计与施工

为了提高稠油热采及小规模砂体的开发效果,大庆油田设计施工了侧钻超短半径水平井J37-26-P14井。该井完钻井深629.62 m,造斜率20°/m,曲率半径仅为3.30 m,造斜段水平位移为2.90 m,总水平位移为22.70 m,水平段长19.58 m。该井施工中存在剖面设计紧凑、地层可钻性差、侧钻难度大、井眼曲率大造成钻具摩阻大等技术难点,在对超短半径的井身结构及井眼轨迹剖面进行优化设计和主要技术难点进行分析的基础上,制定了相应的技术措施,确保该井顺利完钻。该井的顺利完成,为其他侧钻超短半径水平井积累了宝贵经验。详细介绍了该井的设计与施工情况。      

酸性红37光催化降解动力学的响应曲面法优化及其转化机制

为探索单偶氮染料酸性红37 在水溶液中降解的可行性及在活性氧物种作用下可能的迁移转化机制,利用光催化技术并根据中心复合实验设计原理建立了不同因素对酸性红37 光催化降解效率影响的二次回归方程,得出酸性红37光催化降解的最优条件：催化剂（P25TiO2）质量浓度为2.3 g/L,底物浓度为90μmol/L,温度为12.5 ℃,溶液初始pH值为8.7。研究结果表明：水溶液中不同阴阳离子对酸性红37 降解动力学的影响较大,其中Na+、Fe2+、Fe3+和Zn2+ 等对酸性红37 的降解具有明显的抑制作用,而Cu2+则体现了一定程度的促进作用;然而CrO42-、SO42-、ClO3-、MnO4- 和Cl- 则对其降解均体现了不同程度的抑制作用。最后利用气相色谱质谱联用仪对酸性红37的光催化降解产物进行了初步的分离并进行分析,认为光催化过程中酸性红37分子中N=N和C-N键断裂后的进一步羟基化反应是其主要的降解途径。     

地衣芽孢杆菌产Levan果聚糖发酵条件的优化

通过单因素试验(培养基用水、碳源、氮源、培养温度和培养基初始pH值)和正交试验对地衣芽孢杆菌(Bacillus licheniformis)8-37-0-1发酵产生Levan果聚糖的培养基组成及培养条件进行优化,采用苯酚-硫酸法测定多糖含量。结果表明：以蔗糖100g/L、牛肉膏1.0g/L、酵母粉0.6g/L、K2HPO4 3.0g/L、KH2PO4 3.0g/L、NaCl 1.0g/L、MgSO4·7H2O 0.2g/L、FeSO4·7H2O 0.001g/L,自来水配制,培养基初始pH5.0,30℃培养8-37-0-1菌株24h,Levan果聚糖产量达到最高值41.7g/L,约是未优化时的5.0倍。