菜油的应用——芥酸酰胺的制取

本课题研究以菜油为原料的醇解——氨解法.并取得了芥酸酰胺的技术路线和工艺条件,并对其性能和纯度进行了测定.     

单萜烯的超临界液相色谱法研究

用(超)临界液相色谱法分析了单萜烯混合物。该方法操作简单、灵敏度较高、重复性好，在单萜烯的研究中有一定的参考价值。     

DC-8.8湿式电滤器系统改造总结

介绍了湿式电滤器的工作原理以及该系统在生产中出现的工艺和电气等方面的问题,并从多方面提出了改造措施.     

I.L.B.装置在小电网下大型管磨机启停控制中的应用

大型管磨机启停时电压会波动，常规方法是采用一台液体电阻启动器来保证电机启动过程平滑、无冲击。而在小电网下，此法却不尽人意。在越南某水泥粉磨站的水泥磨主电机的供电系统中，成功地将I.L.B装置与液体电阻启动器结合起来，收到事半功倍的效果。     

高质量磷酸三钠生产工艺控制要点

阐述了磷酸三纳生产中关键岗位工艺指标的控制及为降低产品消耗采取的主要措施。通过工艺控制与降低消耗,使产品一级品率达到了１００％,纯碱消耗３４４ｋｇ／ｔ（１００％）,烧碱消耗１６９ｍｇ／ｔ（１００％）。     

Improvement of the magnetic properties of highly porous open-celled magnets

In the present study, we have investigated the influence of B₂O₃ addition on structural and magnetic properties of hard magnetic BaFe₁₂O₁₉ foams. In the presence of B₂O₃ open-celled foams were successfully fabricated at a calcination temperature of 1300 °C. Magnetization values have been improved by 50% with B₂O₃-addition. Remanence magnetization (M_R), specific magnetization at 1.5 T (M_S) and coercive field (H_c) values were obtained to be 32.7 emu/g, 63.0 emu/g and 2100 Oe, respectively for the 0.5 wt% B₂O₃ containing foams having 30 pores/in. Foams with these magnetic properties have the potential to be used in different areas of technology as permanently magnetic materials.     

间歇过滤机工艺操作参数的优化

在本文针对间歇过滤机如何选择适宜操作参数，以实现优化操作进行了讨论     

大剂量纳洛酮配合机械通气雾化戊乙奎醚救治急性有机磷中毒中间综合征的临床研究

目的观察大剂量纳洛酮配合机械通气雾化戊乙奎醚救治急性有机磷中毒中间综合征(IMS)的效果。方法在内科综合治疗基础上,以大剂量纳洛酮(商品名:苏诺)配合机械通气雾化戊乙奎醚(商品名:长效托宁)救治IMS患者57例,计算病死率,并与国内外文献报道病死率进行比较。结果病死率为40.36%,明显低于国内外文献报道62.5%死亡率(P<0.05)结论:本疗法可提高抢救成功率,是救治急性有机磷中毒中间综合征的新途径,值得临床推广应用。     

Estimation of compound classes in coal hydrogenation liquids by thin-layer chromatography

Compound classes in coal liquids were investigated by thin-layer chromatography coupled with a flame ionization detector (t.l.c.-f.i.d.). Individual t.l.c. peaks for coal liquids were identified as paraffins, aromatics, polar compounds and more strongly polar compounds or asphaltenes in order of increasing R_f values by comparison with specific compounds separated previously by conventional liquid chromatography. Concentrations of compound classes for a series of samples obtained by varying the hydrogenation time were estimated and good agreement was found with the results obtained by the USBM-API 60 liquid chromatography procedure. By using the t.l.c.-f.i.d. method, the relation of distribution of compound classes to the reaction conditions of coal hydrogenation could be derived quantitatively with relative ease.     

A chemical demonstration of the randomness of epoxidation of natural rubber

During the development of chemical methods for determining the epoxide content of epoxidised natural rubber (ENR) two methods were found to give results which were identical but which showed a progressive divergence from values obtained by absolute instrumental methods as the level of epoxidation increased. Statistical analysis of the sequence distribution of the epoxide groups, based on a random epoxidation, showed a good correlation between the value obtained by chemical analysis and the number of epoxide blocks rather than the number of epoxide groups. Two further instrumental methods for measuring the total epoxide content, using infra red spectroscopy and differential scanning calorimetry, were developed. Analytical procedures and calibration data are supplied. A combination of one chemical and one instrumental method can thus provide the absolute level of epoxidation and indicate whether the reaction has proceeded randomly or not, a point of crucial importance in the large scale manufacture of this material.     

Influence of chemical and physical properties of the last generation of silicon carbide fibres on the mechanical behaviour of SiC/SiC composite

SiC/SiC composites reinforced with near stoichiometric SiC ceramic fibres (Hi-Nicalon S and SA3 Tyranno fibres) are attractive materials to be used in nuclear environment. Netherless, their mechanical properties must be improved and controlled. For example, SA3 Tyranno fibres (TSA3) -reinforced composites exhibit a brittle behaviour whereas composites reinforced by Hi-Nicalon S (HNS) fibres exhibit a conventional damage tolerant response. This difference is related to the nature of the fibre/matrix (F/M) coupling. The aim of this work was to identify the SiC fibres characteristics influencing the F/M coupling and consequently the mechanical properties of the composites. The experimental results point out that the TSA3 fibres exhibit a granular and rough surface leading to an increase of the residual stress and the interfacial shear stress in the SiC/SiC composites. Beside the roughness, the experimental results also point out that the surface chemistry of the SiC fibres significantly influence the F/M bonding.     

Preparation of self-reinforcement of porous mullite ceramics through in situ synthesis of mullite whisker in flyash body

Self-reinforced porous mullite ceramics were fabricated by a starch consolidation method with flyash, different aluminium sources (Al(OH)₃ and Al₂O₃) and the additive AlF₃ as raw materials. The reinforcement mechanism of needle-like mullite whiskers through in situ synthesis in ceramic body was investigated. The bulk density, apparent porosity and bending strength of the samples were tested. Phase compositions and microstructures of the sintered samples were measured by XRD and SEM, respectively. It showed that AlF₃ as additive was helpful to the formation of mullite whiskers at a low temperature. As the aluminium sources, Al(OH)₃ was more suitable for the preparation of mullite whiskers than Al₂O₃. The in situ synthesized mullite whiskers formed an interlocking structure, which enhanced the mechanical strength of the porous mullite ceramics. Porous mullite ceramics with bending strength of about 100 MPa and apparent porosity of about 55% were made at 1550 °C.     

Surface characterization by X-ray photoelectron spectroscopy and cyclic voltammetry of products formed during the potentiostatic reduction of chalcopyrite

Surface characterization of the transient products that precede chalcocite formation during chalcopyrite reduction was carried out. The experimental strategy employed in the present work consisted of the application of different potential pulses (fixed energetic conditions) on the surface of chalcopyrite electrodes in 1.7 M H₂SO₄. The chemical products formed at different potential pulses were characterized by cyclic voltammetry (CV) and XPS. Each electrogenerated species presented a specific voltammetric behavior and an XPS spectrum, in which the values of principal photoelectronic peak bond energies for Cu 2p_3/2, Fe 2p_3/2 and S 2p_3/2 and the atomic concentrations were considered. Several potential intervals could be identified: in 0.115 ≥ E_cat ≥ −0.085 V vs. SHE, an intermediate copper sulfide is formed whose composition is between those of chalcopyrite and bornite, such as talnakhite. The reduction of this product occurs slowly, giving bornite at potentials less than −0.085 V. In the applied potential region −0.085 ≥ E_cat > −0.185 V, the bornite gradually decomposes causing the incomplete conversion to chalcocite. In the potential interval −0.185 > E_cat ≥ −0.285 V, energetic conditions are large enough to allow the immediate decomposition of bornite, forming chalcocite in a more quantitative manner.     

Micropore structure of activated carbons and predictions of adsorption equilibrium

A method for calculating micropore size distributions based on a molecular model of adsorption and analytical solution for the adsorption isotherm is presented in this study. Micropore volume filling is considered to be an evolution of two-dimensional condensation, which occurs on micropore walls at the critical condensation pressure. The treatment of adsorption isotherms of propane, propylene, acetylene, ethylene, cyclopentane and benzene shows that the method offers a quantitative approach to determining a reliable carbon texture, which is independent of adsorbate employed and adsorption temperature. The invariant parameters of porous structure coupled with molecular constants of adsorbate provide a prediction of the adsorption equilibrium in a wide range of pressures. Good agreement between experimental and calculated data is demonstrated for adsorption of both gases and vapors.     

Usability of electrophoretic deposition for additive manufacturing of ceramics

The potential of electrophoretic deposition of ceramic particles for additive manufacturing of 3D structures is investigated. A custom-made test setup is constructed using a hollow electrode for the supply of a ceramic suspension and a tip c electrode for focused deposition of particles on the surface of a membrane. Parameters like voltage, electrode distance, suspension flow rate, etc. are systematically varied to study their impact on the deposition yield and the morphology of the deposited structures. Experimental work is supported by computer simulations on the electrical field distribution within the electrode area. Although detrimental phenomena like electrohydrodynamic effects occur, we have shown that the technique offers opportunities for future 3D printing of ceramics.     

Influence of shrinkage-reducing admixtures on the reduction of plastic shrinkage cracking in concrete

Fresh concrete exposed to high evaporation rates is prone to plastic shrinkage cracking, especially in structures with large surface area/volume ratios. The present work shows that the reduction of the surface tension of the mixing water is an effective way for decreasing such cracking. In this study, conventional and high strength concretes with superplasticizers and shrinkage reducing admixtures (SRAs) were exposed to drying in the plastic state. Continuous monitoring of the surface displacement facilitated the identification of the different stages of plastic shrinkage cracking. Measurements of capillary pressure, settlement, internal temperature and evaporation rate were also made. The results show the effectiveness of SRAs in reducing plastic shrinkage cracking, even in high strength concrete. This is attributed to the reduction in the evaporation rate, delay of the peak capillary pressure due to the development of menisci in the pores and lower settlement.     

Non-destructive investigations of pore morphology of micropore carbon materials

Pore morphology of experimental micropore carbon materials was explored using non-destructive methods. The influence of the heat treatment on porosity of two micropore carbon materials was investigated using helium porosimetry (HP) and X-ray micro-computed tomography (µCT). Methodology of µCT image processing and separation of the total and the open porosity is presented. In both materials open pores were found over the whole height of the sample. The local pore thickness and tortuosity of the materials were calculated. The increase of the porosity after heat treatment is observed for both materials.     

Processing of thin film ceramic membranes for oxygen separation

Processing of dense and thin ceramic membrane layers for high temperature selective oxygen separation is addressed in this study. Mixed oxygen-ionic and electronic conducting perovskite oxide system based on La_0.2Sr_0.8Fe_0.8Ta_0.2O_3−δ composition is employed for processing of structural and functional layers. Special focus is aimed at obtaining thin layer and final microstructure with particle size in the sub-micron range. Thin layer deposition is performed by dip coating technique using stable colloidal suspension of perovskite particles dispersed within ethanol media. Two polymer based surfactants were screened for their effect on particle agglomeration and rheological response. By using optimum quantity of 2.5 wt.% addition of selected surfactant it is possible to obtain dense 15-60 μm thick functional layers. The thermal cycle applied resulted in final particle sizes within sub-micron range. By employing suspension with pore former it was possible to significantly increase the surface area of the functional layer.     

工业汽轮机的清洗

本文介绍了用饱和蒸汽对冷凝式汽轮机进行清洗除垢时主要参数的确定、操作要点及清洗方案，清洗后的汽轮机运行正常。     

Influence of concentration of hydroxyapatite surface modifier agent on bioactive composite characteristics

The characterization of chitosan – hydroxyapatite (CH – HAp) composite sponges prepared via freeze-drying methodology is reported in this study. Stearic acid (SA), added as a surface modifier of the HAp nanoparticles, induced changes in the TG/DTG results, particle size distribution and particle morphology. Composite sponges prepared with SA coated HAp demonstrated enhanced biocompatibility and structural properties, as compared to the composites prepared with uncoated HAp. SA coating modified the morphology of the composite, promoting a better dispersion of HAp particles within the composite sponges, and better homogeneity of the polymeric cover with HAp particles. The viability of the composites for cell culture applications was analyzed, and the results suggest that the sponges are biocompatible. Therefore, SA proved to be a good candidate for surface coating of HAp nanoparticles prevent agglomerations, and could be used effectively in the preparation of biocompatible composite sponges with chitosan.