Distribution of some trace elements in the H-Coal process development unit

To understand better the distribution and fate of some trace elements in coal liquefaction plant operated in a continuous mode, a study of six typical trace elements—Cd, Pb, Cr, Cu, Mn and Ni—was initiated at the HRI-operated H-Coal Process Development Unit at Trenton, NJ. Sampling was carried out carefully and the analytical effort was designed to prevent sample contamination and produce precise analyses. The results show that the trace elements studied enter the plant and remain associated with the denser, less volatile materials. Under equilibrium conditions there does not appear to be a buildup in the PDU of those trace elements studied.     

ICP-MS法测定扶元降糖胶囊无机元素的含量

目的:测定扶元降糖胶囊中无机元素含量,为探讨其补气降糖机理,提供一定的实验研究数据.方法:微波消解法对该制剂进行消解处理后,利用等离子体电感耦合质谱仪检测其无机元素.结果:测得荷质比在2～260间元素含量.该制剂富含人体有益元素锌、钴、镍、钒、铁等元素,其有害元素汞、铜、铅、镉、砷含量均低于国家药典规定.结论:扶元降糖胶囊富含糖尿病患者所需元素.     

Status of trace element emission in a coal combustion process: a review

Several important aspects are described in this paper. The occurrences of trace elements (TEs) in coal are introduced. Four main groups of trace element content level, say, >50, 10–50, 1–10 and <1 ppm, can be drawn. Trace elements partitioning in emission streams; enrichment in submicron particles; vaporization and emission in flue gas; and the mobility and leaching behavior of trace elements in coal and combustion waste are summarized. The mechanisms of trace element transformation during combustion are illustrated as following: the vaporized metals at high temperature near the combustion flame will subsequently nucleate or condense at a lower temperature downstream. These metals form a suspended aerosol along with particles. The conversion of vaporized components into various solid and/or liquid forms is the key factor influencing the final trace elements' transformation/partitioning behavior. Finally, current trace element emission control technologies are briefly introduced. To control trace elements in particle phase, electrostatic precipitators and fabric filters are mainly used. To control trace elements in vapor phase, spray dryer absorbers, wet scrubbers, condensing wet scrubbers, wet scrubbers and solid sorbent injection should mainly be used. Research needs are identified and potentially promising research topics on trace elements emission are proposed as following: (1) trace element speciation and enrichment in coal and coal ash. (2) Trace elements partitioning in combustion process. (3) Mechanisms of transformation and control technologies for easily vaporized TEs during combustion.     

Influence of Trace Elements on Neurodegenerative Diseases of The Eye—The Glaucoma Model

Glaucoma is a heterogeneous group of chronic neurodegenerative disorders characterized by a relatively selective, progressive damage to the retinal ganglion cells (RGCs) and their axons, which leads to axon loss and visual field alterations. To date, many studies have shown the role of various elements, mainly metals, in maintaining the balance of prooxidative and antioxidative processes, regulation of fluid and ion flow through cell membranes of the ocular tissues. Based on the earlier and current research results, their relationship with the development and progression of glaucoma seems obvious and is increasingly appreciated. In this review, we aimed to summarize the current evidence on the role of trace elements in the pathogenesis and prevention of glaucomatous diseases. Special attention is also paid to the genetic background associated with glaucoma-related abnormalities of physiological processes that regulate or involve the ions of elements considered as trace elements necessary for the functioning of the cells.     

火焰原子吸收光谱法测定当归及其炮制品中的金属元素

测定经不同加工炮制后当归饮片中Fe、Cu、Mg、Ca、Mn、Zn、Ni、Cr、Pb 9种金属元素的含量,并进行比较,分析加工炮制方法对元素含量的影响.采用火焰原子吸收光谱法（FAAS）测定当归生品、清炒当归、当归炭中金属元素的含量.当归清炒后除Cu、Mg和Ca的含量减少外,其余元素含量均增加.当归炭炒后除Cu、Mg和Pb的含量减少外,其余元素含量均有不同程度的增加.不同炮制方法会引起当归金属元素含量产生变化,这为进一步研究当归的炮制机理提供参考数据.     

双扭旋叶片组合形式对管内湍流换热性能的影响

在圆管内一个截面上安装两个扭旋叶片的组合形式会产生多个纵向涡,纵向涡的形式与强弱受相邻两组叶片旋向和错位角的综合影响。为探究各种组合形式对湍流换热性能的影响,研究了6种不同组合形式某一截面上速度与温度梯度和压力梯度的协同程度,得出结论：错位角对Nu和压力降的影响明显大于叶片旋向的改变。在近壁区,增加错位角可以提高速度与温度梯度的协同程度,而且相邻两组叶片旋向相反形式优于旋向相同的形式;但旋向相同形式的速度与压力梯度的协同程度优于旋向相反形式,然而这种差距会随着错位角的增加而减小,当错位角为90°时,在y/R<0.75时协同程度非常接近。     

火焰原子吸收光谱法测定污水处理厂污泥中Pb、Cd、Cr、Ni含量

采用空气-乙炔火焰原子吸收光谱法测定污水处理厂污泥中Pb、Cd、Cr、Ni的含量。研究了灰化温度、灰化时间、消解加酸量对不同金属吸光度的影响。在最佳工作条件下,4种元素标准曲线相关性较好(r=0.997 0～0.999 8),样品加标回收率为96.0%～106.5%,测定结果准确可靠。得出了不同季节生活污泥中Pb、Cd、Cr、Ni含量变化规律。     

ICP-MS定量法和半定量法在水果中微量元素分布分析中的应用

为了解ICP-MS定量和半定量法在水果中微量元素分布分析中的应用,通过ICP-MS的定量法和半定量法分别测定了桑葚、蓝莓、车厘子、樱桃和杨梅5种水果中的K、Mg、Fe、Na、Rb、Mn、Zn、Ba、Al、Sr、Ti、Cu、Ga、Co等微量元素含量。结果表明:1)桑葚、蓝莓、车厘子、樱桃和杨梅中都含有丰富的微量元素,且这些元素的分布特点是同一种水果中K含量最高,Mg含量次之,Co含量最低;不同种水果中元素分布均不一致。2)在这些元素中,除Rb外,其他元素之间均有一定的相关性。3)定量法和半定量法的测定结果之间没有显著性差异。     

Production of clean fuels by solvent skimming of coal at around 350 °C

The authors have recently presented a new coal extraction method by which various kinds of coals ranging from brown coals to bituminous coals could be extracted up to 80% of the parent coals in a flowing stream of tetralin or a coal derived oil, carbol oil, under 10 MPa at 350 °C. The extract obtained by this method was almost free from inorganic materials. In this study the effect of solvent recycling on the extraction behavior was examined to make the method practically applicable. The solvent recycling was found to be effective in enhancing the extraction yield and in decreasing further the inorganic fraction in the extract. The extract and residue obtained were characterized through various analyses. To examine how inorganic materials are removed by the extraction, the contents of inorganic elements, including harmful trace elements, in the extract were investigated. It was clarified that the presented method was effective in the removal of most of the inorganic elements including even harmful trace elements from coals, although the degree of removal was dependent on the kind of element.     

Mechatronics using piezoelectric actuators

Mechatronics has enabled “intelligent” machinery such as car antiskid braking systems to be created. Any new automotive development has to incorporate a large number of mechanical servo functions, and the range of functions and requirements in servo technology is growing apace. New actuator technologies, therefore, give fresh impetus to product development and accelerate progress. Piezoelectric actuators represent a new technology that offers a host of advantages. In combination with signal-processing electronics, the good mechanical and electrical integratability of piezoelectric actuators make these devices key elements in innovative, intelligent systems. This paper presents prototype applications. Particular attention is focused on powerful large-displacement piezoelectric actuators. The article also includes concrete characterization of piezoelectric actuator elements. To this end specific static and dynamic measurement methods were developed to characterize the elements under temperature and load influences.     

水溶性叶面肥对豇豆产量的影响

使用8个不同配方叶面肥在豇豆营养生长阶段喷施3次,调查叶面肥对豇豆产量的影响。结果表明,与对照相比,喷施4.3%黄腐酸叶面肥处理增产67.0%;8%黄腐酸＋氮磷钾增产57.1%;大量元素＋微量元素[（N＋P2O5＋K2O≥23%9∶6∶8）＋（F e＋B＋Z n≥1%）]的增产48.2%;4%腐植酸钾＋大量元素＋微量元素[（N＋P2O5＋K2O≥23%9∶6∶8）＋（Fe＋B＋Zn≥1%）]增产43.2%（添加腐植酸钾不利于提高产量）;3%腐植酸钾＋维生素＋尿素＋硫酸钾≥7%增产40.8%;大量元素＋微量元素[（N＋P2O5＋K2O≥35%12∶10∶13）＋（F e＋B＋Z n≥0.6%）]增产39.5%;3%腐植酸钾＋大量元素＋微量元素[（N＋P2O5＋K2O≥35%12∶10∶13）＋（F e＋B＋Z n≥0.6%）]增产33.7%;4%腐植酸钾增产15.9%。黄腐酸增产效果最明显,微量元素增产效果比大量元素明显,腐植酸钾增产幅度较低,腐植酸钾＋大量元素＋微量元素处理的增产效果低于大量元素＋微量元素处理。     

视觉化学

视觉的产生是感光色素－视紫红质发生光化学反应的结果，为了提高视力，需要注意摄入适量的维生素A和微量元素锌。     

烟草中痕量金属元素分析方法的研究进展

综述了近年来烟草中痕量金属元素分析方法的研究进展。探讨了样品的前处理技术,并对原子光谱法、分子光谱法、离子色谱法等方法进行了归纳和评述;展望了烟草中痕量金属元素分析方法的研究方向和发展前景。     

一种新的基于可拓理论的工业过程生产操作方法(英文)

To explore the problems of dynamic change in production demand and operating contradiction in production process, a new extension theory-based production operation method is proposed. The core is the demand requisition, contradiction resolution and operation classification. For the demand requisition, the deep and comprehensive demand elements are collected by the conjugating analysis. For the contradiction resolution, the conflict between the demand and operating elements are solved by the extension reasoning, extension transformation and consistency judgment. For the operating classification, the operating importance among the operating elements is calculated by the extension clustering so as to guide the production operation and ensure the production safety. Through the actual application in the cascade reaction process of high-density polyethylene (HDPE) of a chemical plant, cases study and comparison show that the proposed extension theory-based production operation method is significantly better than the traditional experience-based operation method in actual production process, which exploits a new way to the research on the production operating methods for industrial process.     

Partitioning of elements in a entrained flow IGCC plant: Influence of selected operational conditions

The partitioning of trace elements and the influence of the feed conditions (50:50 coal/pet-coke feed blend and limestone addition) was investigated in this study. To this end feed fuel, fly ash and slag samples were collected under different operational conditions at the 335 MW Puertollano IGCC power plant (Spain) and subsequently analysed. The partitioning of elements in this IGCC plant may be summarised as follows: (a) high volatile elements (70->99% in gas phase): Hg, Br, I, Cl and S; (b) moderately volatile elements (up to 40% in gas phase and ?60% in fly ash): As, Sb, Se, B, F, Cd, Tl, Zn and Sn; (c) elements with high condensation potential: (>90% in fly ash): Pb, Ge, Ga and Bi; (d) elements enriched similarly in fly ash and slag 30-60% in fly ash: Cu, W, (P), Mo, Ni and Na; and (e) low volatile elements (>70% in slag): Cs, Rb, Co, K, Cr, V, Nb, Be, Hf, Ta, Fe, U, Ti, Al, Si, Y, Sr, Th, Zr, Mg, Ba, Mn, REEs, Ca and Li. The volatility of As, Sb, and Tl and the slagging of S, B, Cl, Cd and low volatile elements are highly influenced by the fuel geochemistry and limestone dosages, respectively.     

陶瓷泥浆间歇式磁选机磁场有限元分析

用有限元方法对陶瓷泥浆间歇式磁选机的磁场分布进行了分析,将螺线管磁系简化为轴对称问题,采用高精度三解形单元,得到陶瓷泥浆间歇式磁选机磁场分布规律;采用有限元方法计算陶瓷间歇式磁选机的磁场分布对磁选机的设计计算具有重要意义。     

固体吸附剂对油页岩半焦燃烧过程中重金属元素的影响

通过对桦甸油页岩半焦进行燃烧实验,研究了不同终温下部分重金属元素的挥发特性及吸附剂的吸附效果,研究表明：随着温度的增加,各元素的挥发率均呈现出增大的趋势,且当温度为650℃时,元素Cd、Te、Co、Sn、Pb、Sb的挥发率呈现出明显的增大趋势;相对而言,各温度段下元素Cd、Te的挥发率较大,元素Mn、Y、W的挥发率较低。添加吸附剂CaO和高岭土后,大部分元素在页岩灰中的含量均明显增加,表明吸附剂对大部分重金属元素具有良好的吸附效果;通过吸附率可以看出,吸附剂CaO除元素W、Te未发现吸附效果外,对其他所研究的重金属元素均有较强的吸附效果,尤其是元素Co、Mn、Cu、Y、Sn、Cd;而高岭土除对元素Pb、Te未发现吸附效果外,对其他元素均具有一定的吸附效果,尤其是元素Co、Mn。相比而言,CaO对重金属元素的吸附效果要比高岭土强。     

Comparison of the fixation of heavy metals in raw material, clinker and mortar using a BCR sequential extraction procedure and NEN7341 test

The release potential and leaching behavior of five heavy metals (As, Cd, Cr, Cu and Pb) in raw material, clinker and mortar were studied by the three-step sequential extraction procedure proposed by the commission of the European Communities Bureau of Reference (BCR) and NEN7341 leaching test. The results of two experimental methods were compared to show the fixation difference of heavy metals among three kinds of samples. The results of NEN7341 leaching test show that the maximum leached concentration of cement products is low and the leached fraction of five heavy metals represents less than 15% of the total heavy metal content of the cement product. To refer to the bulk content as a criterion of environmental impact is not appropriate. The results of sequential extraction procedures show that the bonding forms of heavy metals change a lot in three samples. The contamination factor (Cf) and the leached fraction of each element in three samples indicate that all the elements are better fixed in cement products than in raw material due to calcination and hydration. To most elements, the relative metal retention is higher in mortar than in clinker. Compared within the five analyzed elements, Cd is better retained and Cu is worse retained in the same kind of sample.     

A review of the electrochemical corrosion behaviour of iron aluminides

The objective of this review is to outline the aqueous corrosion research activities being undertaken on iron aluminides. Key results are extracted and reviewed from publications covering the past 25 years of research activity in aqueous corrosion behaviour of iron aluminides. This review deals with phenomena, which are related with electrochemical corrosion such as passivation and repassivation kinetics, breakdown of passivity, chemistry of the passive film and mechanism of passivation. The role of constituent elements and the effect of alloying elements on the corrosion behaviour of iron aluminides have also been discussed. To assess corrosion resistance of iron aluminides a comparative study was put up with that of stainless steels.     

Investigation of combination of finite element formulation and element type on the accuracy of 3D modeling of polymeric fluid flow in an extrusion die

The aim of this work is to investigate the effect of finite element formulation and element type on the accuracy of 3D modeling of generalized Newtonian fluid flow in complex domains. Computer models based on three finite element solution schemes (mixed, continuous, and discrete penalty), and two element types (hexahedral and tetrahedral) in a 3D framework were developed. The well‐known Carreau model was used to reflect the rheological behavior of the fluid. To determine the validity of the developed computer simulations, the flow of two high‐density polyethylene (HDPE) melts with different viscosities through an extrusion die was simulated and compared with experimentally measured data. Comparison showed that the three methods produced nearly the same results with the hexahedral elements. However, continuous penalty method using tetrahedral elements demonstrated an extreme discrepancy from the experimental data. Discrete penalty method was unable to predict secondary variable (pressure) accurately using tetrahedral elements. The best results were obtained by the use of mixed method in conjunction with tetrahedral elements. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011