真丝绸产品的清洁生产与生态设计

通过对真丝绸整个产品生命过程的分析，对其进行了生命周期评价，说明了丝绸与其产地环境之间的联系和影响，尝试寻求两者之间的和谐关系，提出了清洁生产工艺的规划和各种行之有效的对策和措施，尝试了对环境友好的丝绸印染工艺的生态设计。     

Thermomechanical fatigue—damage mechanisms and mechanism-based life prediction methods

An existing extensive database on the isothermal and thermomechanical fatigue behaviour of high-temperature titanium alloy EVII 834 and dispersoid-strengthened aluminum alloy X8019 in SiC particle-reinforced as well as unreinv conditions was used to evaluate both the adaptability of fracture mechanics approaches to TMF and the resulting predictive capabilities of determining material life by crack propagation consideration. Selection of the correct microstructural concepts was emphasised and these concepts were, then adjusted by using data from independent experiments in order to avoid any sort of fitting. It is shown that the cyclic /-integral (δJ_eff concept) is suitable to predict the cyclic lifetime for conditions where the total crack propagation rate is approximately identical to pure fatigue crack growth velocity. In the case that crack propagation is strongly affected by creep, the creep-fatigue damage parameter δ_CF introduced by Riedel can be successfully applied. If environmental effects are very pronounced, the accelerating influence of corrosion on fatigue crack propagation can no longer implicitly be taken into account in the fatigue crack growth law. Instead, a linear combination of the crack growth rate contributions from plain fatigue (determined in vacuum) and from environmental attack is assumed and found to yield a satisfactory prediction, if the relevant corrosion process is taken into account.     

Corrosion fatigue of extruded magnesium alloys

Corrosion fatigue tests were carried out on extruded AZ31 (3% Al, 1% Zn, 0.3% Mn, Mg—the rest), AM50 (5% Al, 0.4% Mn, Mg—the rest) and ZK60 (5% Zn, 0.5% Zr, Mg—the rest) Mg alloys in air, NaCl-based and borate solutions. N_sol/N_air ratios (the relative fatigue life) were used for the analysis of the corrosion fatigue behavior of Mg alloys in various environments, where N_sol and N_air are the numbers of cycles to failure in the solution and in air, respectively. Extruded ZK60 alloy reveals very high fatigue and corrosion fatigue properties in comparison with other alloys. However, it has the lowest relative fatigue life (N_sol/N_air 10⁻³–10⁻²) or the highest sensitivity to the action of NaCl-based solutions in comparison with that of AM50 and AZ31 alloys (N_sol/N_air 10⁻²–10⁻¹). Under the same stress, the corrosion fatigue life of extruded alloys is significantly longer than that of die-cast alloys (N_sol for extruded AM50 in NaCl is two to three times longer than that of die-cast AM50).     

Is the Promissory Note of Personality as Vulnerability to Depression in Default? Reply to Zuroff, Mongrain, and Santor (2004).

In contrast to D. C. Zuroff, M. Mongrain, and D. A. Santor (2004), the current authors find the promissory note of dependency-sociotropy (DEP-SOC) and self-criticism-autonomy (SC-AUT) as a model of risk for depression to be in default. The authors propose reorganizing what has been cast as unitary effort into 3 distinct endeavors: a psychoanalytic clinical theory, development of a refined empirical model of risk for clinical depression, and research examining the effects of DEP-SOC and SC-AUT on interpersonal relationships in nonclinical samples. The authors identify some issues that need to be accommodated regardless of whether the assessment of Zuroff et al. (2004) or their own is accepted. DEP-SOC and SC-AUT are best construed as correlated, continuous dimensions. Future work also needs to accommodate depression as chronic recurrent condition, advances in developmental psychopathology, and more stringent criteria for positing a risk factor for clinical disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stability analysis of an adaptive packet access scheme for mobile communication systems with high propagation delays

In this paper, we investigate a packet access scheme that is able to support mixed traffics in the presence of high propagation delays. Referring to a Time‐Code Division Multiple Access air interface, we propose a Medium Access Control (MAC) protocol based on a random access scheme. A successful attempt grants the use of a slot‐code resource. This protocol is named Adaptive Time Code‐Packet Reservation Multiple Access (ATC‐PRMA), since the access parameters are changed, depending on the traffic load conditions, so as to fulfil Quality of Service requirements. Numerical examples are carried out for the Low Earth Orbit (LEO)‐Mobile Satellite System (MSS) scenario, but all these considerations could be applied to High‐Altitude Platform Stations (HAPSs) as well. In both cases, high propagation delays prevent an immediate feedback to users. An analytical approach is proposed to study the stability of our MAC scheme. Accordingly, we define a criterion for optimizing system performance. The predicted ATC‐PRMA behaviour is supported by simulation results. Finally, we show the performance improvement of ATC‐PRMA with respect to a MAC protocol not employing adaptive parameters. Copyright © 2003 John Wiley & Sons, Ltd.     

Investigation on the flocculation of asphaltenes and the colloidal stability of the crude oil fraction (> 210°C)

Several problems are encountered with asphaltenes during the exploitation, transportation, storage and treatment of crude oil. The purpose of the present work was to study the behaviour of the crude oil fraction (<210°C) by varying the temperature and doping with some hydrocarbons including solid paraffin and aromatic concentrate. The effect of flooding water was investigated. A preliminary characterization study on asphaltenes removed from the crude oil using two different solvents was performed. The state of the oil was determined by the stability factor which indicates the susceptibility of asphaltenes to agglomerate or to disperse in the continuous phase.     

Extraction of penicillin G from simulated media by an emulsion liquid membrane process

The extraction of penicillin G from simulated media was performed by water/oil/water (w/o/w) emulsion liquid membranes (ELMs) and studied under various operational conditions in a batch system. The degree of extraction achieved was between 80% and 95% under specific conditions. A concentration of greater than nine times the initial concentration of penicillin G in the external phase was obtained in the internal phase. The pH of the internal aqueous solution, containing a basic salt, was theoretically calculated on the basis of the amount of penicillin G transported into the internal phase. The calculated results agreed with the experimental data well and were used to select a suitable type and concentration of a basic salt in the internal phase to give a pH within the range 5 to 8 where penicillin G was stable after the termination of extraction. The extraction of penicillin G was successfully performed by the ELM process with sodium carbonate in the internal phase.     

多变量加权多步预报控制*

对于线性多变量系统,本文给出了一种完全不同于以往的全状态反馈或观测器-控制器型的算法——多变量加权多步预报控制(MWLPC)算法。这种算法除引进了预测控制中的多步输出预报、滚动优化等机制外,最重要的是在二次型性能指标中引入了可调的多项式或有理分式矩阵权因子;适当选取这些权因子,便可按设计要求、仅用系统的输出信息反馈便能任意配置闭环系统的特征矩阵,从而保证闭环稳定性和其他优良性质。此外,该算法不改变原系统的零点,因而适用于非最小相位系统。     

对索风营水电站坝址区堆积体勘察设计的几点认识

乌江索风营水电站坝址区分布有7个堆积体,其成因有崩塌堆积、蠕变-拉裂-崩解堆积、塌滑堆积及混和堆积等.在勘察过程中采用了地质测绘、钻探、硐探、物探、科研试验等多种勘察方法与手段,在勘察成果基础上对堆积体稳定性进行了分析,并结合对工程的不同影响提出了相应的工程处理措施.