排塔自振特性的有限元分析与实验研究

本文对工业中的排塔的自振特性进行了有限元分析，并通过排塔模型实验对有限元计算结果进行了验证。通过实验与计算结果分析，提出了计算排塔平面内振动一阶自动振率的简化公式。     

100台塔设备自振周期的实测与分析

本文对塔型设备自振周期进行探讨,将现有常用理论公式的计算结构与实测进行对比,然后根据100台落地塔的实测周期,采用数理统计分析,提出计算自振周期的经验公式,并对经验公式作了分析。     

100台塔设备自振周期的实测与分析

本文对塔型设备自振周期进行探讨，将现有常用理论公式的计算结构与实测进行对比，然后根据１００台落地塔的实测周期，采用数理统计分析，提出计算自振周期的经验公式，并对经验公式作了分析。     

对钢制塔式容器自振周期计算的修正

采用传递矩阵法计算了塔设备的自振周期和振型。通过几何回归，对ＪＢ４７１０－９２中不等直径或不等厚度塔器的一阶振型假设进行了修正。采用修正后的振型，能提高塔设备自振周期的计算精度。     

计算塔设备自振频率的有限单元法

利用梁弯曲振动的有限单元法，编制了ＦＯＲＴＲＡＮ有限元计算程序，用以计算结构载荷分布、约束条件复杂的等截面、变截面直立塔设备诸振型的自振频率。计算结果与ＧＢ１５０－９８《钢制压力容器》中计算公式所得计算结构及实验数据比较，证明本方法有较高的计算精度，且比现有公式有更广泛的应用范围。     

直立塔设备自振周期的计算方法

简述了直立塔设备自振周期的计算方法 ,通过计算实例的比较 ,对计算方法进行了研究与评述 ,指出了各种计算方法所适用的范围     

悬挂式塔设备自振频率的计算

对于不同的支承条件 ,分别提出了简支的悬挂塔与固支的悬挂塔自振频率的计算方法。计算方法还与有限元法进行了对比 ,取得了令人满意的结果。文中还对最适宜的支座位置进行了探讨     

尿素造粒塔温度应力计算方法探讨

为探讨尿素造粒塔的实际环向温度分布,对比了壳体结构在内外温差作用下温度应力的现有计算方法和<尿素造粒塔设计规范>计算方法;采用SAP 2000有限元程序对某造粒塔的温度应力进行了温差计算、理论计算和有限元分析,并与规范计算结果进行了比较.结果表明,直接使用长圆柱壳热弹理论计算的造粒塔温度应力值比实际值偏小,建议对规范计算结果进行修正.     

框架塔动力特性的有限单元法研究

利用大型有限单元程序ANSYS对框架塔的自振频率进行了模拟计算 ,并将计算值与试验值进行了对比。在此基础上 ,对框架塔的参数 ,即刚度比与相对高度对自振频率与位移响应的影响进行了探讨 ,并给出了在设计框架塔时适宜的框架高度。     

65台框架支承式塔设备自振周期的实测与分析

对６５台框架塔的自振周期和振型进行实测,发现基本振型与落地塔不同,塔体呈弯曲变形而框架部分呈剪切变形。根据实测自振周期进行数理统计分析提出自振周期经验公式。并用哈密顿原理,推导出计算振型的理论公式可供设计应用。     

Controlled supercontraction tailors the tensile behaviour of spider silk

The interest in the production of fibres that mimic the behaviour of natural silks has been boosted by the first successful attempts of spinning fibres based on spider drag line silk proteins. However, both the processing of biomimetic silk fibres and the basic studies on silk are hampered by the large variability of the fibre properties. Here we show that the tensile behaviour of spider silk can be predictably and reproducibly tailored by controlling the supercontraction effect, a large shrinkage of the longitudinal dimension of the fibre if unrestrained by its ends and immersed in water. This procedure allows to reproduce the tensile behaviour of natural drag line fibres and offers the possibility of obtaining silk fibres with predictable tailored properties in large quantities for experimental use. These results can be interpreted in the frame of the molecular model of drag line silk, as the result of re-orientation of the protein chains, leading to an explanation for the observed variability of natural drag line fibres.     

电感耦合等离子发射光谱仪不确定度的评定

测量不确定度是对测量结果可信性、不效性的怀疑程度或不肯定程度,是定量说明测量结果质量的一个参数,其大小直接决定测量结果的可用性。介绍了电感耦合等离子体发射光谱仪(ICP-OES)的工作原理,依据JJF 1059-1999《测量不确定度评定与表示》和JJG 768-2005《发射光谱仪检定规程》,用美国热电公司的IRIS-intrepid型电感耦合等离子体发射光谱仪测量Zn、Ni、Mn、Cr、Cu、Ba多元素混合系列标准溶液,并通过对混合标准溶液检测数据的处理,进行电感耦合等离子体发射光谱仪测量结果的不确定度分析和评定。     

电感耦合氩等离子发射光谱法分析精对苯二甲酸中的杂质

采用电感耦合氩等离子发射光谱法分析精对苯二甲酸中的十八种杂质,校正了元素特征发射线的位置,选出了定量线,考察了雾化气压力、泵速、辅助气流速和高频发生器功率对元素定量线信号强度的影响。各元素标准曲线相关系数在0．9981至1．000之间;分析结果最大相对误差8.3％,最大相对标准偏差2．5％;加标回收率92．2％-112％;此外,与原子吸收光谱法进行了对比试验。该法是原子吸收光谱法和其他元素分析方法理想的替代方法。     

Dynamic Scaling in Chemical Ecology

Natural rates of chemical production, release, and transport of fluid-borne molecules drive fundamental biological responses to these stimuli. The scaling of the field signaling environment to laboratory conditions recreates essential features of the dynamics and establishes ecological relevance. If appropriately scaled, laboratory simulations of physical regimes, coupled with natural rates of chemical cue/signal emission, facilitate interpretation of field results. From a meta-analysis of papers published in 11 journals over the last 22 years (1984-1986, 1994-1996, 2004-2006), complete dynamic scaling was rare in both field and laboratory studies. Studies in terrestrial systems often involved chemical determinations, but rarely simulated natural aerodynamics in laboratory wind tunnels. Research in aquatic (marine and freshwater) systems seldom scaled either the chemical or physical environments. Moreover, nearly all research, in all environments, focused on organism-level processes without incorporating the effects of individual-based behavior on populations, communities, and ecosystems. As a result, relationships between chemosensory-mediated behavior and ecological function largely remain unexplored. Outstanding exceptions serve as useful examples for guiding future research. Advanced conceptual frameworks and refined techniques offer exciting opportunities for identifying the ecological significance of chemical cues/signals in behavioral interactions and for incorporating individual effects at higher levels of biological organization.     

Delivery of cisplatin by folic acid-targeted liposomal nanoparticles into liver cancer cell line

This study aimed to prepare cisplatin-loaded PEGylated liposomal nanoparticles targeted with folic acid and evaluate their efficacy on liver cancer cell line PLC/PRF/5 (Alexander hepatoma cell line). Nanoparticles were prepared by reverse phase evaporation technique and characterized by dynamic light scattering, scanning electron microscopy, transmission electron microscopy, inductively coupled plasma optical emission spectrometry, Fourier transform infrared spectroscopy, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide techniques. Nanoscale particles with appropriate drug encapsulation efficiency (13%) were prepared. Cytotoxicity results indicated that the superior potency of targeted cisplatin-loaded nanoparticles compared to the nontargeted counterpart with 23% more cytotoxicity. Findings of this study confirmed the potency of targeted PEGylated liposomal nanoparticles.     

Reverse osmosis for the production of aromatic concentrates from mussel cooking juices: a technical assessment

An industrial mussel cooking juice was concentrated by reverse osmosis (11-fold) after a desalination step by electrodialysis in order to produce a natural aroma concentrate and a clean water stream. The concentrate quality was evaluated by a trained sensory panel (triangular tests, sensory profiles) and by gas chromatography coupled with mass spectrometry (GC-MS). About 34% of the aroma compounds were lost, inducing a slight modification of the sensory profile of the concentrate compared to the unprocessed mussel cooking juice one. This modification was not obstructing because this concentrate can be used in industrial recipe with a routine rate (10–15%) for natural aroma concentrates. In addition, as a result of this process the polluting load of the permeate was strongly reduced. The chemical oxygen demand was below the discharge standards.     

Identification of a Female-Specific, Antennally Active Volatile Compound of the Currant Stem Girdler

We identified (Z)-9-octadecen-4-olide as a female-specific, antennally active compound from the currant stem girdler Janus integer Norton. Female specificity was demonstrated by gas chromatographic comparison of liquid chromatography fractions of male and female volatile emissions and whole body extracts. The -lactone was identified by coupled gas chromatographic-electroantennographic detection (GC-EAD), coupled gas chromatographic-mass spectrometric (GC-MS) analysis, microchemical reactions, and GC and MS comparison with authentic standards. GC-EAD analysis of female volatile emissions and cuticular extracts showed a single peak of activity on male antennae, which was not present in male-derived materials. Female antennae did not respond to any of the tested materials. The hydrogenation product of the natural EAD-active material was a known saturated -lactone. The mass spectrum of the dimethyl disulfide derivative of the natural -lactone was consistent with a double bond present in the 9 position. Comparison of the natural -lactone and a synthesized racemic mixture of (Z)-9-octadecen-4-olide on a chiral GC column showed the presence of a single enantiomer in the natural material.     

Influence of natural convection on the heat explosion in porous media

The interaction between natural convection and the heat explosion in porous media is studied. The model consists of a nonlinear heat equation coupled with the Darcy equation for the motion of an incompressible fluid in a porous medium. Numerical simulations are performed using the alternate direction finite difference method and the fast Fourier transform method. A complex behavior of solutions is observed, including periodic and aperiodic oscillations and an oscillating heat explosion. It is shown that convection can decrease the risk of the explosion due to additional mixing and heat loss, but it can also facilitate the explosion due to temperature oscillations arising as a result of instability of stationary convective regimes.     

Identification of 1-Hydroxypyrene Photoproducts and Study of the Effect of Humic Substances on its Photolysis

Photolysis products of 1-hydroxypyrene (1-HP) were identified by liquid chromatography coupled with mass spectrometry (LC/MS/MS). It was found that the major photoproducts of 1-HP are 1,6-, 1,8-, and one unidentified pyrene quinone and one pyrene quinone dimer based on their HPLC chromatogram and mass spectral data. The photolysis of 1-HP was conducted with pure water, natural river water, and pure water containing commercial humic substances. It was found that the photolysis rate of 1-HP can be inhibited by humic substances, depending on their type and concentration.     

油田注入水源与储层的化学配伍性研究

采取离子浓度变化分析及浊度法进行了天然海水与地层水的静态配伍性研究;应用岩心流动实验进行了动态配伍性研究.结果表明,涠12-1油田注入水源与地层水不配伍,且温度越高不配伍性越严重,对岩心损害程度越大;天然海水驱替过程中,随着驱替体积增加,累积结垢程度变大;天然海水与地层水交替驱对岩心损害严重,渗透率降低达32.3%.因此不能用天然海水直接作注入水源.