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。     

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。     

Temperature and composition dependent excitonic luminescence and exciton-phonon coupling in CdSeS nanocrystals

ABSTRACT: The yellow- and red-emitting CdSeS nanocrystals (NCs) synthesized through one-step organometallic synthesis method are uniformly assembled in polymethyl methacrylate (PMMA). A higher-energy emission band originates from band-edge excitonic state appeared at low temperature. With the Se dopant concentration increasing, the luminescent spectra of CdSeS NCs have a red-shifted emission peak and a shorter luminescent lifetime, which is attributed to the existence of trapping state caused by surface defect and Se dopant. CdSeS NC shows a shorter luminescence lifetime and higher energy emission peak in PMMA matrix than that in toluene, indicating that the former is more favorable to transfer energy through exciton-phonon coupling. The upconversion luminescence (UCL) is observed using 800nm femtosecond laser excitation. The pump power dependence demonstrated UCL spectra of yellow-emitting CdSeS NCs has a slope of 2.2, while that of red-emitting CdSeS NCs has a slope of 1.4. The results demonstrate that the two-photon absorption plays a dominating role when Se concentration of CdSeS NCs is lower, while phonon-assisted UCL by one-photon excitation gradually takes place with the amount of Se dopants increasing.     

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.     

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.     

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％）。     

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.     

反射器壳体注塑模具的设计

介绍反射器壳体注塑模具的设计、制造及其特点。     

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。     

Characterisation of separated melamine—formaldehyde adducts (methylolmelamines) and adduct mixtures by h.p.l.c. and by n.m.r. and u.v. spectroscopy

Most of the individual methylolmelamines that occur in melamine–formaldehyde adduct mixtures have been separated by preparative high-performance liquid chromatography (h.p.l.c.) and recovered in amounts sufficient to allow their characterisation by high-field ¹H- and ¹³C-n.m.r. Particular attention has been paid to the chemical shifts of the aromatic azine carbons of the melamine nuclei. These carbon shifts are shown broadly to be in agreement with some values previously published, but additional assignments have been made. It is shown that a satisfactory quantitative analysis of the methylolmelamines in a melamine–formaldehyde adduct mixture can be carried out either by h.p.l.c. or by ¹³C-n.m.r.     

Liquefaction reaction of coal: 2. Structural correlation between coal and its liquefaction products

The structural correlation between coal and its liquefaction products has been examined using cross-polarization, magic angle spinning (CP/MAS) ¹³C n.m.r. and field ionization mass spectrometry (f.i.m.s.). The CH₂/aromatic carbon ratios of all solid products (asphaltene, preasphaltene and residue) were close to the corrected +CH₂/aromatic carbon ratio for the coal. This suggests that the ring structure of the structural unit of each solid product is essentially similar to that of the parent coal, except for a difference in the degree of polymerization of the structural units. The CH₂/aromatic carbon ratios of aromatic ring-type oil fractions also correlated with the corrected ratio for the coal, although they were larger. The z series distribution obtained from the f.i.m.s. of oil fractions revealed that coal with a higher CH₂/aromatic carbon ratio produced an oil rich in naphthenic structures.     

In-situ monitoring of the stabilization with hydrogen of free radicals thermally induced from coal using high pressure e.s.r., d.t.a. and p.d.a. equipment

High temperature, high pressure e.s.r. measurements of the hydrogenation reaction of Taiheiyo coal in the presence of catalysts were carried out to understand the stabilization of thermally and/or catalytically induced free radicals. A decrease in free radical concentration with increasing temperature was observed for ZnCl₂ and SnCl₂ · 2H₂O catalysts at 10MPa under hydrogen gas. High pressure modified single-cell d.t.a. and p.d.a. equipment augmented the uniquely designed high temperature, high pressure e.s.r. cell. The hydrogenation reaction was monitored under the same experimental conditions as for e.s.r. From the results of the combination of high temperature, high pressure e.s.r. with high pressure d.t.a. and p.d.a., it was established that H₂ molecules can react efficiently with free radicals from coal molecules created by the presence of ZnCl₂ and SnCl₂ · 2H₂O catalysts.     

复合材料电性能在微波频段的测量

介绍复合材料在微波频段介电常数的测量方法和测量图，讨论各种技术的优缺点，以及测量误差和不确定性。     

Degradation of alumina refractory bricks by sintering Mn low-alloy steels

The economic importance of the corrosion and wear of refractory materials is indisputable because these processes determine the viability of any high-temperature liner used in metallurgical processes. The degradation mechanism of lining materials (refractory bricks) in contact with corrosive gases can be studied by examining the penetration rate or the chemical corrosion that results from the circulation of the atmosphere over the refractory material (by diffusional and convective transport). During the sintering of steel containing Mn, the high vapour pressure of Mn enables its sublimation during thermal cycling; therefore, Mn is incorporated into the sintering atmosphere. Although the diffusion of Mn in steel samples is beneficial, the presence of Mn in a sintering atmosphere can modify the composition of refractory components. As a result of atmosphere-refractory interactions, a new phase is formed. In this study, the changes in refractory materials as a function of exposure time to atmospheres containing Mn_(g) at the most common sintering temperature, 1120 °C, were investigated. The microstructural changes in the refractory materials and the consequences of the presence of Mn_(g) were analysed using optical microscopy, electron microscopy with X-ray (EDS) microanalysis, X-ray diffraction, and X-ray fluorescence (XRF).     

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.     

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.     

Preparation and characterization of a nigerian mesoporous clay-based membrane for uranium removal from underground water

This study reports the removal of uranium in underground wastewater using a Nigerian clay-based membrane. The clay and sintered clay were characterized using XRD, XRF, TGA/DTA, FESEM and PSD. The raw clay was mixed with cassava starch (10, 15, 20 and 25 wt%) and sintered at a temperature of 1300 °C. A multi-point BET analysis of the produced clay-based membranes was conducted to determine the surface area, pore volume and average pore size. Sintering characteristics were determined by apparent porosity, bulk density and flexural strength. The radioactivity of the feed and the permeated water was counted using a gamma spectrometer with an HPGe detector. From the XRD, TGA and FESEM, 1300 °C was found to be optimum for the mullite formation from the clay. The average pore sizes of the produced membranes from the BET results were observed to be in the range from 51 to 70 Å and with a steady state flux range of the tested membranes in the range 1.92×10⁻⁵–2.09×10⁻⁴ m³ m⁻² s⁻¹. The permeation flux produced is of high quality with a rejection in the range of 1.78–2.56 Bq/l of the uranium activity by the tested membranes. This low-cost membrane will have an application for the treatment of uranium-containing wastewater from fracking, oil exploration and phosphate mining industries.     

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.     

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