高效旋风分离器尺寸的确定

<正> 本文介绍了一种旋风分离器的快速设计方法,该法可提供最佳设计结构,并考虑到固体粒子密度。虽然使用了试差法,但仅经几次试差即收敛。     

Second-order advantage achieved with four-way fluorescence excitation-emission-kinetic data processed by parallel factor analysis and trilinear least-squares. Determination of methotrexate and leucovorin in human urine

Four-way fluorescence data recorded by following the kinetic evolution of excitation-emission fluorescence matrices (EEMs) have been analyzed by parallel factor analysis and trilinear least-squares algorithms. These methodologies exploit the second-order advantage of the studied data, allowing analyte concentrations to be estimated even in the presence of an uncalibrated fluorescent background. They were applied to the simultaneous determination of the components of the anticancer combination of methotrexate and leucovorin in human urine samples. Both analytes were converted into highly fluorescent compounds by oxidation with potassium permanganate, and the kinetics of the reaction was continuously monitored by recording full EEM of the samples at different reaction times. A commercial fast scanning spectrofluorometer has been used for the first time to measure the four-way EEM kinetic data. The rapid scanning instrument allows the acquisition of a complete EEM in 12 s at a wavelength scanning speed of 24 000 nm/min. The emission spectra were recorded from 335 to 490 nm at 5-nm intervals, exciting from 255 to 315 nm at 6-nm intervals. Ten successive EEMs were measured at 72-s intervals, to follow the fluorescence kinetic evolution of the mixture components. Good recoveries were obtained in synthetic binary samples and also in spiked urine samples. The excitation, emission, and kinetic time profiles recovered by both chemometric techniques are in good agreement with experimental observations.     

Direct determination of carbohydrates, amino acids, and antibiotics by microchip electrophoresis with pulsed amperometric detection

The separation and detection of underivatized carbohydrates, amino acids, and sulfur-containing antibiotics in an electrophoretic microchip with pulsed amperometric detection (PAD) is described. This report also describes the development of a new chip configuration for microchip electrophoresis with PAD. The configuration consists of a layer of poly(dimethylsiloxane) that contains the microfluidic channels, reservoirs, and a gold microwire, sealed to a second layer of poly(dimethylsiloxane). Example separations of carbohydrates, amino acids, and sulfur-containing antibiotics are shown. The effect of the separation and injection potentials, buffer pH and composition, injection time, and PAD parameters were studied in an effort to optimize separations and detection. Detection limits ranging from 6 fmol (5 microM) for penicillin and ampicillin to 455 fmol (350 microM) for histidine were obtained.     

新桥硫铁矿一期坑采接替延伸工程开工建设

铜陵化学工业集团有限公司新桥硫铁矿一期坑采 6 0万ｔ/ａ硫铁矿工程的接替延伸工程于 7月 8日正式开工建设。该工程总投资 80 0 0万元 ,预计可采工业储量2 10 0万ｔ ,按年采 6 0万ｔ规模计算 ,服务年限 35年左右。该工程采用主副井原位延伸法 ,将原一期坑采的 - 2 30ｍ中段分别下延至 - 2 70ｍ、 -330ｍ、- 330ｍ三个中段 ,基建期预计为两年半。此项工程的设计方案于 1998年 11月 30日通过专家审查 ,今年 2月对其中的部分工程进行了招标 ,安徽省中煤三建第三十工程处中标承建其中的主井井筒掘、砌等工程。该项工程的开工建设将为新桥矿调整…     

利用模糊综合评判评价注水管道腐蚀程度

注水管道腐蚀机理研究，需要进行注水管道的腐蚀程度评价。对腐蚀地面注水管道的腐蚀程度定量评价，能全面了解注水管道腐蚀情况基础，同时也是对注水管道剩余强度评价、剩余寿命预测以及可靠性分析的关键，为水质处理流程、缓蚀剂、杀菌剂和防垢剂等筛选提供了科学依据。提出了利用模糊综合评判方法对注水管道进行腐蚀程度评价的具体方法，通过应用示例验证了该评价方法的实用性。     

裂缝高度影响因素分析及控缝高对策技术研究

在水力压裂和酸压过程中,裂缝会沿着缝高方向延伸.当裂缝延伸超出产层进入上下隔层时,不仅造成压裂液资源的浪费,而且难以达到设计要求.研究压裂过程中控制裂缝在高度方向上延伸的诸因素,分析了单因素条件下的裂缝高度变化趋势.针对不同因素对裂缝高度的影响,调研了针对这些因素的控缝高压裂技术.     

泥炭泥浆在治疗中的放射性

正为确定泥炭泥浆中天然和人工同位素的含量,并估算标准泥炭泥浆处理过程中患者皮肤吸收的辐射剂量,分析了从波兰8个矿泉采集的37个样本,用γ能谱法测量同位素浓度活性。标准泥炭泥浆浴治疗中的皮肤剂量约为300 nSv,泥炭泥浆这种治疗的有效剂量被认为是22 nSv。治疗过程中     

Features of the motion of gel particles in a three-phase bubble column under foaming and non-foaming conditions

Features of the motion of gel particles in a three-phase bubble column with non-foaming and foaming gas–liquid systems,determined by using experiments of radioactive particle tracking(RPT),have been compared.The tracer used is a gel particle which resembles typical immobilized biocatalyst.The tracer trajectory is analyzed to extract relevant information for design purposes.The solid velocity field,turbulence parameters,dispersion coefficients,mixing times and flow transitions are determined and compared.The presence of foam significantly affects many quantified parameters,especially within the heterogeneous flow regime.The hydrodynamic stresses are reduced in the presence of foam,especially close to the disengagement.The dispersion coefficients also decrease,and the solid mixing time is only slightly affected by the presence of foam.Gas holdup,inferred both from RPT experiments and from gamma ray scanning,is higher for foaming systems and leads to a shift in the transition gas velocity towards higher values.