PYRITE PARTICLE SIZE DISTRIBUTION AND PYRITIC SULFUR REDUCTION IN CRUSHED COALS: A PRELIMINARY REPORT

ABSTRACT

Six bituminous coals were ground to 28, 100, and 400 mesh x 0, and examined by optical automated image analysis (AIA) to estimate their pyrite particle size distributions and degree of liberation (DOL). These data were used to determine the feasibility of estimating specific-gravity-based pyritic sulfur reduction by AIA methods. Preliminary results indicate that further research is warranted. A review of the progress is presented.     

Extraction of mass spectra and chromatographic profiles from overlapping GC/MS signal with background

An adaptive immune algorithm (AIA) was proposed for resolution of the overlapping GC/MS signal with background. By using AIA, the chromatographic profiles corresponding to the independent components (ICs) in the overlapping signal are calculated with the mass spectra extracted by means of independent component analysis (ICA). The number of the ICs in the overlapping signal is determined by the difference between the reconstructed and the original data. Both simulated and experimental data are investigated with the proposed AIA approach. It was found that the mass spectra and chromatographic profiles of the components in an overlapping multicomponent GC/MS signal can be accurately resolved with the existence of background, and the results are better than that by using an interactive self-modeling mixture analysis (SIMPLISMA) method. The AIA approach may be a promising tool for the resolution of overlapping GC/MS signal.     

Adaptive inverse analysis (AIA) applied and verified on various fiber reinforced concrete composites

During the past decades several inverse approaches have been developed to identify the stress-crack opening (\({\sigma }-w\)) by means of indirect test methods, such as the notched three point bending-, wedge splitting-, and round panel testing. The aim is to establish reliable constitutive models for the tensile behavior of fiber reinforced concrete materials, suitable for structural design. Within this context, the adaptive inverse analysis (AIA) was recently developed to facilitate a fully general and automatized inverse analysis scheme, which is applicable in conjunction with analytical or finite element simulation of the experimental response. This paper presents a new formulation of the adaptive refinement criterion of the AIA method. The paper demonstrates that the refinement criterion of the nonlinear least square curve fitting process, is significantly improved by coupling the model error to the crack mouth opening and the crack opening displacement relationship (\(w_{\mathrm{cmod}}-w_{\mathrm{cod}}\)). This enables an adaptive refinement of the \({\sigma }-w\) model in the line segment with maximum model error, which entails significant improvement of the numerical efficiency of the AIA method without any loss of robustness. The improved method is applied on various fiber reinforced concrete composites and the results are benchmarked with the inverse analysis method suggested by the Japanese Concrete Institute (Method of test for fracture energy of concrete by use of notched beam, Japanese Concrete Institute Standard, Tokyo, 2003) and recently adopted in ISO 19044 (Test methods for fibre-reinforced cementitious composites—load-displacement curve using notched specimen, 2015). The benchmarking demonstrates that the AIA method, in contradiction to the JCI/ISO method, facilitates direct determination of the tensile strength and operational multi-linear \({\sigma }-w\) models.     

自适应免疫算法的SVME用于水下目标识别

针对用支持向量机集成提高水下目标识别正确率会使识别系统更加复杂的问题,提出了一种以自适应免疫算法(AIA)的支持向量机选择性集成(SVME)算法(即AIA-SVME算法)进行分类器优化选择,对实测水下目标声信号进行分类识别.与分类器全部集成的识别实验对比证明,该算法在选择9%的分类器后仍可以达到分类器全部集成的识别效果,不仅保证了识别精度,还使得识别系统大幅度精简,节省在线识别的时间.该研究对于水下目标分类决策优化集成的新方法探索具有重要理论价值和实际意义.     

DEVELOPMENT OF AN AUTOMATIC SYSTEM FOR COUNTING ASBESTOS FIBERS USING IMAGE PROCESSING

Atmospheric concentrations of carcinogenic asbestos fibers, have traditionally been measured visually using phase contrast microscopy. However, because this measurement method requires great skill, and has poor reproducibility and objectivity, the development of automatic counting methods has been long anticipated. We have developed the Asbestos Fibers Automatic Counting System (AFACS), and verified its accuracy via application to illustrations obtained from the Asbestos Internationa) Association (AIA). Important features of the AFACS system are as follows:

(1) Counting criteria of the automatic counting system conform to those of visual counting

(2) The cost of the whole system is low because it is microcomputer-based.     

DEVELOPMENT OF AN AUTOMATIC SYSTEM FOR COUNTING ASBESTOS FIBERS USING IMAGE PROCESSING

ABSTRACT

Atmospheric concentrations of carcinogenic asbestos fibers, have traditionally been measured visually using phase contrast microscopy. However, because this measurement method requires great skill, and has poor reproducibility and objectivity, the development of automatic counting methods has been long anticipated. We have developed the Asbestos Fibers Automatic Counting System (AFACS), and verified its accuracy via application to illustrations obtained from the Asbestos Internationa) Association (AIA). Important features of the AFACS system are as follows:

(1) Counting criteria of the automatic counting system conform to those of visual counting

(2) The cost of the whole system is low because it is microcomputer-based.     

Integrating the Boyer Report into Architectural Engineering Technology Education at the University of Hartford

Building Community: A New Future for Architectural Education and Practice by Ernest L. Boyer and Lee D. Mitgang of the Carnegie Foundation for the Advancement of Teaching, 1996, was intended to be a “comprehensive study of education and practice for the 21st century.” It was commissioned by the five national architectural organizations that joined together with a common goal of seeing the need for an independent study of professional education and practice: the American Institute of Architects (AIA), the Association of Collegiate Schools of Architecture (ACSA), the American Institute of Architects Students (AIAS), the National Council of Architectural Registration Board (NCARB), and the National Architectural Accrediting Board, Inc. (NAAB). The Boyer report identified problems, opportunities, and challenges not only for the primary audience of architecture educators and practitioners but also others in higher education. Boyer and Mitgang challenged architects and educators to “a new vision.” This vision would connect architecture schools and the profession more effectively to the changing social context. The academy was challenged with providing A Connected Curriculum. Practicing architects were challenged with providing A Unified Profession. The Boyer report, “urged schools to prepare future architects for lives of civic engagement, of Service to the Nation” [1]. The authors of Building Community were optimistic that the challenges could be met and we have taken on this challenge.     

Fabrication of multi-walled carbon nanotube reinforced polyelectrolyte hollow nanofibers by electrospinning

Hybrid hollow multi-walled carbon nanotubes (MWCNTs)/polyelectrolytes (PE) nanofibers were prepared by a combination of the electrospinning method and layer-by-layer (LbL) technique. The mixed polystyrene (PS)/MWCNTs nanofibers were obtained by electrospinning method, which were employed as templates to self-assembly multilayered polyelectrolytes by LbL technique. Hollow MWCNTs/PE nanofibers were obtained by selectively removed part of the template: PS, which is confirmed by Raman spectra, transmission electron microscopy (TEM) and scanning electron microscopy (SEM).     

海藻酸钠/聚乙烯亚胺凝胶球的合成及对Cr(Ⅵ)的吸附性能和机制

海藻酸钠(SA)是一种生物质材料,具有来源广泛、价格低廉的特性,被众多科研人员用于实验室研究,制备成吸附剂去除水溶液中的金属离子.但目前制备的大多数SA基吸附材料是实心水凝胶状,具有比表面积较低、吸附速率慢、吸附容量小的缺点.本研究以SA为基体,向其中添加碳酸钙和聚乙烯亚胺(PEI),以戊二醛为交联剂,经冷冻干燥后制备...     

壳聚糖/羟基磷灰石表面修饰聚己内酯多孔骨支架的制备及性能

采用选择性激光烧结技术构建多孔聚己内酯(PCL)骨支架,用原位合成的方法制得壳聚糖/羟基磷灰石(CS/HA)悬浮液,并采用真空浸泡、低速离心和冷冻凝胶的方法使CS/HA黏附在PCL支架的表面,以改善骨支架的生物相容性和细胞增殖活性。通过X射线衍射(XRD)和扫描电子显微镜(SEM)观测复合支架的物相和形貌,测量支架的压缩强度和杨氏模量,测量支架表面的水接触角,并通过体外细胞实验研究复合支架的生物学性能。实验结果表明,原位合成的方法制得了羟基磷灰石(HA);CS/HA凝胶与PCL骨支架表面黏附良好;CS/HA改善了PCL支架表面的亲水性,提升了骨支架的生物相容性和细胞增殖活性。     

DHDOPO接枝改性多壁碳纳米管及其对聚乳酸性能的影响

首先将多壁碳纳米管(p-MWCNTs)用混合浓酸氧化成羧基化MWCNTs(MWCNTs-COOH),然后与氯化亚砜(SOCl_2)反应得酰氯化MWCNTs(MWCNTs-COCl);将9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)与二乙醇胺(DEA)反应制备DOPO的衍生物DHDOPO;再将DHDOPO与MWCNTs-COCl进行接枝反应得表面功能化的MWCNTs(MWCNTs-COO-DH);最后经熔融共混法制备聚乳酸(PLA)/MWCNTs-COO-DH复合材料。用核磁共振氢谱和透射电子显微镜表征MWCNTs-COO-DH的结构和微观形貌;用电子万能试验机、扫描电子显微镜、微型燃烧量热计等测定PLA/MWCNTs-COO-DH复合材料的力学性能、冲击断面形貌、燃烧性能及残炭层形貌。结果表明,实验成功合成了目标产物DHDOPO,并将其接枝到MWCNTs表面形成了典型核-壳结构的MWCNTs-COO-DH;适量的MWCNTs-COO-DH可均匀分散在PLA基体中形成良好的界面结合;质量分数为0.1%的MWCNTs-COO-DH可显著提高PLA的力学性能,并能降低其可燃性和火灾危险性。     

聚（N-异丙基丙烯酰胺-co-丙烯酸）/Fe3O4复合微球的制备及表征

采用Fe3O4、N-异丙基丙烯酰胺(NIPAM)和丙烯酸(AA)制备了具有磁敏、温敏和pH敏感的多重敏性复合微球。先使用共沉淀法制备Fe3O4磁性纳米颗粒,并用油酸对其改性。继而采用种子聚合法制备P(NIPAM-co-AA)磁性微球。研究表明,在pH值为10的合成条件下,复合微球的分散性较好。采用疏水性引发剂可相对增加有机、无机相之间的亲和性。通过扫描电镜(SEM)、红外光谱(FT-IR)、动态光散射(DLS)和超导量子干涉磁强计(SQUID)等对微球进行了结构与形态表征,结果证明,复合微球形貌统一,各组分之间聚合良好。复合微球的粒径约为249 nm,对温度、pH可作出预期的响应,饱和磁化强度为40 emu/g。     

改性埃洛石复配聚磷酸铵对硅橡胶阻燃性能和力学性能的影响

为研究埃洛石对硅橡胶阻燃性能和力学性能的影响,将埃洛石经乙烯基三甲氧基硅烷(A-171)表面改性处理后与聚磷酸胺(APP)复配并用于硅橡胶基体中,经机械共混制备了复配填充改性埃洛石(m-HNTs)的阻燃硅橡胶复合材料(FRSR)。利用红外光谱、热重分析对m-HNTs进行表征分析,采用扫描电子显微镜、极限氧指数(LOI)、垂直燃烧、锥形量热、能谱仪、热重分析等对FRSR的力学性能、阻燃性能、残渣形貌及热降解行为进行研究,并与复配填充未改性HNTs的样品性能对比。结果表明,复配填充适量的m-HNTs后,FRSR阻燃性能明显改善,力学性能显著提高。当复配填充3phr m-HNTs时,拉伸强度达8.7 MPa,LOI值达31.4%,UL-94测试为V-0级,且残渣致密紧实,热阻隔效果好,残炭率高,热释放速率降低36%。     

CF-CNTs多尺度增强体的制备及CF-CNTs/环氧树脂复合材料力学性能

利用化学气相沉积(CVD)法在碳纤维(CF)表面生长碳纳米管(CNTs),制备了CF-CNTs多尺度增强体,增强体与环氧树脂(EP)结合得到CF-CNTs/EP复合材料。采用场发射扫描电镜(FESEM)、高分辨透射电镜(HRTEM)等方法研究了不同CVD工艺参数对CF-CNTs多尺度增强体的影响,并研究了不同CVD时间对CFCNTs/EP复合材料力学性能的影响。结果表明:沉积温度为500℃、沉积时间为10min、反应压力为0.02 MPa时,制备得到的多尺度增强体性能最好。CF-CNTs多尺度增强体较未生长CNTs的碳纤维与环氧树脂的浸润性明显提高。在CVD时间为10min时,所得CF-CNTs/EP复合材料的界面剪切强度(IFSS)最大可提高90.6%,层间剪切强度(ILSS)最大可提高24.4%。同时,在制备环氧树脂复合材料过程中碳纤维的不加捻与加捻相比,其ILSS提高了11.3%。     

含氟嵌段共聚物蜂窝状多孔膜制备与表征

采用原子转移自由基聚合(ATRP)方法,合成聚苯乙烯(PS)大分子引发剂,再引发甲基丙烯酸十二氟庚酯制备嵌段共聚物(PS-b-PDFHMA)。将嵌段共聚物与纳米二氧化钛(TiO_2)复合,利用静态呼吸图法制备抑菌性多孔膜。通过傅里叶变换红外光谱、核磁共振氢谱、凝胶渗透色谱等对嵌段共聚物结构、组成及相对分子质量进行分析和表征;利用扫描电子显微镜对多孔膜表面形貌和膜层结构进行观察;利用接触角测试仪和微生物粘附实验研究多孔膜表面润湿性及对微生物粘附的影响。结果表明,以水滴为模板的多孔膜相较于不含孔薄膜疏水性有一定改善,但细菌粘附量提高,与TiO_2复合后,多孔膜表面粗糙度上升,水接触角可达136°,其表面细菌粘附量明显下降。     

聚乙二醇单甲醚/聚己内酯嵌段共聚物的微波合成及胶束制备

微波辅助下聚乙二醇单甲醚(MPEG)引发ε-己内酯(ε-CL)开环聚合合成了聚乙二醇单甲醚/聚己内酯(MPEG-b-PCL)嵌段共聚物,利用核磁共振(1H-NMR)和凝胶渗透色谱(GPC)方法对共聚物结构进行了表征。以芘作荧光探针,研究了共聚物胶束的形成及其临界胶束浓度(CMC)),利用动态光散射(DLS)和透射电镜(TEM)分别研究了胶束的粒径分布和形态。结果表明,在微波辅助下MPEG能够在较短时间内引发ε-CL开环聚合得到嵌段共聚物,当反应时间为5min,微波功率为700 W时能够得到理想的目标共聚物;嵌段共聚物在一定条件下能够形成球形的单分散纳米级胶束,CMC的数量级为10-3mg/mL。     

γ辐射对麦秸粉/PBSPBAT复合材料性能的影响

为了提高聚丁二酸丁二醇酯（PBS）基复合材料的性能,降低生产成本,采用熔融共混法制备了麦秸粉/PBS-聚己二酸-对苯二甲酸丁二醇共聚酯（PBAT）复合材料,利用⁶⁰Co-γ射线对该复合材料进行了辐射改性。研究了辐射改性对麦秸粉/PBS-PBAT复合材料力学性能、热稳定性和热变形温度的影响,并采用FTIR和SEM表征了复合材料的结构和断面形貌。结果表明：当三烯丙基异氰脲酸酯（TAIC）的含量为1wt%时,复合材料经30 kGy剂量辐射后,其拉伸强度、弯曲强度和冲击强度分别提高了20%、23.5%和6.5%;辐射改性提高了复合材料的高温分解速率,使其热变形温度上升了约11℃,并增强了复合材料组分间的粘结性。     

Development of optical coatings for 157-nm lithography. I. Coating materials

In a basic study to identify low-loss optics for applications in F2 lithography, five potential coating materials (AlF3, Na3AlF6, MgF2, LaF8, and GdF3) and three deposition methods (thermal evaporation by a resistance heater and by electron beam and ion-beam sputtering) were investigated in the vacuum ultraviolet (VUV) region. Samples were supplied as single-layer coatings on CaF2 substrates by four Japanese coating suppliers. Refractive indices (n) and extinction coefficients (k) of these coatings at 157 nm were evaluated; the transmittance and the reflectance were measured by a VUV spectrometer and were compared. As a result, resistance heating thermal evaporation is seen to be the optimal method for achieving low-loss antireflection coatings. The relation among optical constants, microstructures, and stoichiometry is discussed.     

水滑石/硅橡胶复合材料的制备及性能

水滑石经过对苯二甲酸(TPA)插层后与硅橡胶复合制成复合材料。采用XRD、TG以及其它分析手段对样品进行了表征和研究。结果表明,对苯二甲酸的插层率达到79%以上,而硅橡胶大分子的"插层率"为38%;水滑石/硅橡胶样品的力学性能、邵尔A硬度、热稳定性和阻燃性能均有所改善,水滑石添加量以6%为宜;水滑石的分散程度对硅橡胶复合材料的性能有决定性影响。