Effects of Formulation Parameters and Process Variables on the Properties of Granules Obtained by Reactive Granulation

In this work, granulation between dodecyl-benzenesulfonic acid and sodium carbonate was investigated in a laboratory-scale high shear mixer. The effects offormulation parameters and process variables, including primary carbonate size, binder content, impeller speed, and operating temperature, were correlated to the properties ofthe product granules. Design ofexperiment and analysis ofvariance were combined to analyze the experimentaldata, and results showed that larger granule sizes with fewer fine particles can be obtained by employing higher binder contents and larger sodium carbonate sizes. The shear force ofthe impeller can extensively break oversized granules. The binder content exerted a contrasting effect on the flowability ofgranules formed with two kinds ofsodium carbonate, likely because ofdifferences in the liquid saturation ofthe solids. The dissolution rate determined by in-line size analysis showed that high binder contents were beneficialto dissolution performance, and the relationships between Hunter color and tested parameters were evaluated. The results ofthis work can be used as a reliable guidance for process controland optimization in powder detergent manufacturing.     

Effect of Non-reactive Powder Particle Properties on Dry Agglomeration in a High Shear Mixer

The effect of non-reactive powder particle properties on the detergent dry agglomeration process in a high shear mixer was investigated. Three types of micron-scale silica were chosen as the non-reactive fine powders and a semi-solid alkyl ethyl ethoxy sulfate(AES) paste with ultra-high viscosity was chosen as the binder. The granules were characterized using massbased granule size distribution, scanning electron microcopy, and bulk density tests. The results revealed that powder particle size plays a leading role in agglomeration behavior. A decrease in the median particle size results in enhanced dispersion of silica particles in the AES paste binder droplets, which leads to the formation of uniform granules that are slightly affected by compacting forces. Agglomerate quality, using silica with high oil absorption as well as optimum particle size, was satisfactory, and the product exhibited a smaller median particle size, narrower size distribution, and superior anti-caking capacity under the same liquid-to-solid ratio(L/S).     

环十二烷空气氧化制环十二醇的研究

本实验从工程放大角度出发,着重研究了以偏硼酸为催化剂,反应温度和搅拌速率对环十二烷氧化反应的影响,在搅拌鼓泡釜中,适宜反应温度为160～170℃,搅拌转速1500rpm以上,通空气量100ml/g烷.hr,催化剂用量5％,转化率可达30～32％,选择性达73～89％,总收率80～98％(重量百分比)。     

基于SSA的黔中城市群产业结构演变研究

城市群是工业化、城市化进程中,区域空间形态的高级现象,它能够产生巨大的集聚经济效益,影响着一国城市化发展的水平和质量,对经济发展具有重要意义。以尚处雏形状态的黔中城市群为研究对象,运用偏离一份额分析法研究黔中城市群内各区域产业结构,借以促进城市群内各区域进行产业结构调整,加快整个贵州省的经济发展。     

原油降凝剂研究的进展

对原油降凝剂的结构、合成、降凝机理及应用工艺等方面的研究进展情况进行了评述和讨论．     

Agglomeration Control of Ultrafine Y_2O_3-ZrO_2 and (MgO, Y_2O_3)-ZrO_2 Powders Synthesized by Coprecipitation Process

TheadventofstrongandtoughZrO2 basedce ramicshasgeneratedconsiderablescientificandtech nologicalinterestinthisclassofstructuralceram ics[1—3]. Nowfine grainedsinteredceramicscanbeproducedusingcommerciallyavailableultrafinepow ders,whichcanbesinteredtofulldensityatrelativelylowtemperatures. High qualityZrO2 powderisvitalforthesuccessfuldevelopmentofadvancedZrO2 ce ramics. Severalwetchemicalmethodshavebeende velopedforpreparationofsuchhigh purity, homoge neousandsinterableceramicspowders,…     

Surveillance,Governmentality and moving the goalposts: The influence of Ofsted on the work of schools in a post-panoptic era

This paper asks the question: to what extent do inspection regimes, particularly the Office for Standards in Education (Ofsted), influence the work of a school, and how might that influence be conceptualised? It draws on an ESRC-funded study of ‘policy enactments in secondary schools’, which was based on case-study work in four ‘ordinary’ schools. Here the data set is re-examined to understand the extent to which Ofsted had an ongoing influence on the work of the leadership, management and teachers in these schools. We undertook a process of secondary analysis of the data from the project and found that the influence of the inspection agenda was strong in the schools, policy decisions were often being made to conform to Ofsted’s expectations and the influence on leadership and management was clearly apparent. In resisting this agenda we also found that schools to some extent performed ‘the good school’ for inspections. Finally, we relate this empirical evidence to conceptions of governmentality and post-panopticism to shed new light on their theoretical relevance to contemporary inspection regimes.     

图纸扫描误差分析及变形误差纠正

目前,地图的扫描数字化已成为G IS领域中获取数据信息的主要手段之一;从图纸的扫描数字化过程中的误差来源研究入手,分析了地图扫描数字化各项误差对成果质量的影响特征及其大小;就图幅变形误差和应采取的纠正方法进行了试验研究,得出的结论已在土地利用数据库建设等项目的实施过程中得到应用,取得了很好的效果。     

丁集首采面采空区遗煤自燃动态数值模拟

通过对影响煤炭自燃因素的分析,建立了采空区内遗煤自燃过程数学模型,可随时预测不同漏风强度和不同推进速度条件下,采空区遗煤自然发火的危险性,对丁集煤矿1262（1）首采面采空区遗煤自燃过程中,氧化时间、工作面推进速度对煤温的影响进行了计算机模拟,成功预报了在回采过程中采空区遗煤不自燃,确保了该工作面安全回采。     

机械力化学辅助作用下制备木质活性炭的工艺研究

研究采用机械力化学辅助作用下制备高吸附性能木质活性炭,探讨了研磨时间、浸渍比（磷酸与绝干杉木屑的质量之比,下同）、磷酸浓度对所制备活性炭的碘吸附值和亚甲基蓝吸附值的影响;同时,采用比表面积及孔隙分析仪和傅立叶红外光谱仪（FT-IR）对活性炭的表面官能团、比表面积、孔容及孔径分布等进行了表征.分析显示：经过机械力化学辅助作用处理后,机械力化学激活作用有利于木屑与磷酸之间发生更多的化学反应,同时促进更多纤维素发生热解;此外,机械力化学辅助作用可能降低了纤维素热解过程中聚合及芳构化阶段的温度;通过N2吸附等温线分析表明机械力化学法所制备活性炭具有丰富的微孔结构.     

Fed-Batch Fermentation for Spinosad Production in an Improved Reactor

As a kind of aerobic bacteria, Saccharopolyspora spinosa exhibits a high demand for oxygen. In the fermentation process, the methods of increasing ventilation and improving agitation speed are usually adopted to achieve higher values of dissolved oxygen. These methods decrease the efficiency of spinosad biosynthesis.In this study, an improved reactor was designed to solve these problems. The exhaust gas reflux device, impellers,and baffles were improved. Furthermore, we established the kinetic models for the cell growth, substrate consumption and spinosad generation in batch fermentation process. The simulation results were in good agreement with the experimental data. Spinosad production reached 583.86 mg/L after employing the suitable feeding strategy by fed-batch fermentation in the improved reactor, whereas it was only 157.01 mg/L before optimization. The method described can provide insight to strengthen spinosad production and can be extended to the culturing process of filamentous aerobic bacteria.     

Transitive Relational Mappings in Three- and Four-Year-Olds: The Analogy of Goldilocks and the Three Bears

3 experiments examined the ability of a group of 3- and 4-year-old children to make transitive relational mappings based on size. In the first experiment, the children were asked to map relative size from 1 array of objects to another when the absolute sizes of the stimuli were either identical or different, and when the spatial positions of the relationally similar stimuli in each array were also either identical or different. In the second experiment, the concrete representation of size relations between the arrays was varied by asking the children to map relative size to relative proportion. In this cross-representational mapping task, the spatial position of the relationally similar stimuli was again either identical or different. In Experiment 3, the children were asked to map relative size to a variety of different perceptual dimensions including temperature, pitch, and loudness. This more abstract mapping task required the use of mentally represented transitive relations. Each experiment presented the mapping task using the analogy of Goldilocks and the Three Bears. The results are discussed in terms of theories of structure mapping and the development of logical reasoning.     

Formation mechanism and size prediction of bubble in opposite-flowing T-shaped microchannel

Bubble formation in an opposite-flowing T-shaped microchannel with 40 μm in depth and 120 μm in width was real-time visualized and investigated experimentally by means of a high speed camera. N2 bubbles were generated in glycerol-water mixtures with different concentrations of surfactant sodium dodecyl sulfate (SDS). And the images were captured by the high speed camera linked to a computer. Results indicated that the bubble formation process can be distinguished into three consecutive stages, i.e., expansion, collapse and pinching off. The bubble size decreases with the increase of liquid flow rate and viscosity of liquid phase as well as the decrease of gas flow rate. The surface tension of the liquid phase has no measurable influence on the bubble size. Moreover, a new approach to predicting the size of bubbles formed in the T-shaped microchannel is proposed. And the predicted values agree well with the experimental data.     

Determination of particle size distribution by multi-scale analysis of acoustic emission signals in gas-solid fluidized bed

Particle size distribution (PSD) is an important parameter in the process of fluidization, and it always plays a crucial role in a gas-solid fluidized system. A PSD model for on-line PSD determination based on acoustic emission (AE) measurement was developed according to the mechanism of particle collision with the inner wall of the cylinder and multi-scale wavelet decomposition analysis. This PSD model illuminates the quantitative relationship between the energy percentage of AE signals for different scales and the PSD, which indicates the feasibility of the application of the PSD model. Experiments were undertaken both in lab and plant gas-solid fluidized setup with polyethylene particles, and the parameters of the PSD model were calibrated and revised. The experimental conditions and results proved that the PSD model was suitable for on-line measurement and was sufficiently sensible and accurate. Concerning agglomeration, the PSD model also showed exact serviceability on detecting the onset of agglomeration by abnormal PSD, and the result agreed with that from the radiation method. Ultimately, AE measurement was found to be a reliable and credible means for understanding the PSD information that affects the behavior of a system, which can provide valuable guidance for practical applications.     

中原城市群等级规模结构演变分析

选用1993、1998、2004年三个阶段,从中心城市首位度、城市中心性、城市规模结构、空间分布结构等几个方面来分析中原城市群十余年来等级规模结构的演变特征,并提出在中原城市群发展过程中存在的问题以及解决这些问题的相关对策。     

不同变形条件的HPS485wf钢动态再结晶仿真

为了揭示HPS485wf钢动态再结晶组织演变行为,在不同的单道次热压缩变形条件下,进行了该钢动态再结晶过程的CA仿真．结果表明：随着变形温度升高,动态再结晶的孕育期缩短、速度加快,平均晶粒尺寸增加;随着应变速率加快,动态再结晶的孕育期延长、速度减慢,平均晶粒尺寸减小．     

浅析高层建筑物对环境的影响

现代经济高速发展,城市高层建筑对集聚城市人口、集约城市经济、利用城市空间等方面起到积极作用,然而高层建筑对城市环境的影响也日益突出。高层在建筑物当地气候、高层建筑地下环境、居民心理和疾病控制四个方面对环境产生不利影响,而在节约土地、节能新风和部分视觉三方面对环境产生积极影响。     

Kinetic Study of Hydrothermal Stripping from Iron-Loaded Organic Phase

The iron-loaded organic phase of naphthenic acid-isooctyl alcohol-kerosene was prepared, and the process kinetics of hydrothermal stripping of iron from the phase was studied. Several factors affecting hydrothermal stripping, such as the polymer of naphthenic acid, initial concentrations of iron and naphthenic acid, temperature and agitation time, were investigated, and based on experimental results and theoretical analysis, two kinetic models were established.The stripping rate equation suggests that the hydrothermal stripping process activation energy is 96.4 kJ·mol-1 and the stripping is controlled by hydrolysis of naphthenic complex of iron. The values calculated by the stripping fraction equation comparatively accord with the experimental data.     

基于正交试验的过共晶Al-20Si合金变质工艺优化设计

基于L9(34)正交试验,本文对过共晶Al-20Si合金进行变质处理。通过直观和方差分析,确定最佳的变质工艺参数。结果表明：正交试验最佳的工艺参数为A2B2C1D2,变质工艺参数为0.04%的P添加量,0.6%的RE混合稀土添加量,20 min的变质时间以及780℃的变质温度,此时初生Si相转变为规则的六边形,平均尺寸为24.84μm,共晶硅相细化明显;因素A （P添加量）对变质效果有显著影响,B、C、D因素（分别为RE混合稀土添加量、变质时间和变质温度）对变质效果有一定的影响作用,各因素的影响程度分别为P添加量>RE混合稀土添加量>变质温度>变质时间。     

Hydrostatic settling velocity of sediments

The settling of sediments is an accelerative process in which the concentration of the main sediments zone will heavily influence settling velocity，but the explicit relationship between the concentration and settling velocity has not been reported in literature. Here a theoretical function was built for the time dependent concentration and time dependent settling velocity of sediments；then the entire settling process reflecting concentration was shown on the basis of sediments instant-settlement theory and mathematical method. Agreement of computed results and experimental data was found. Several governing parameters，including particle size，particle density，initial suspended sediments concentration and suspension height，were discussed with a series of calculated velocity curves. The research indicated that ⑴ the presented concentration-velocity time relationship is rational，⑵ settling process of the sediments group with variation of concentration consists of acceleration stage，uniform motion stage and deceleration stage，and ⑶ particle size，particle density and initial suspended sediments concentration have more influence on the settling velocity than the suspension height and water temperature.