Impact of forest ditching on nutrient loadings of a small stream--a paired catchment study in Kronoby,W. Finland

The effect of ditching of boreal forest land (W. Finland) on P and N dynamics and export was assessed using a paired catchment approach (response stream + control stream) for a 4-year study period. After the ditching operations, there was a small but significant increase in the NH4+ export, but no significant changes in the concentrations and loads of total reactive P, total non-reactive P, total organic N and NO3-. In both streams, the reactive P fraction largely followed the Fe concentrations. High input to output ratios, and thus, high retention was a typical feature of the inorganic N compounds. Total organic N and the TOC/TON ratio were positively correlated with the total organic carbon.     

Logic of the image

In this the Centennial Year of Alvar Aalto's birth a plethora of events and writings have emanated from sources independent of his origins. Juhani Pallasmaa has lived and worked in the cultural ambience of a world figure in a small country. In reviewing the inheritance of any architect who in his early career prompted a semi-official meeting of the Finnish Architects' Association to 'stop the daredevil before he could cause irreparable harm to the reputation of the esteemed profession' and now is held in such awe that sober critical evaluation has become seriously compromised, he provides fresh insight into Aalto's 'synthetic and inclusive architecture' as landscape, as typology, as tactile experience, as rational structure, as episodic sequence, as 'haptic experience'.     

Effect of Austenite Pancaking on the Microstructure,Texture, and Bendability of an Ultrahigh-Strength Strip Steel

The effect of austenite pancaking in the non-recrystallization regime on microstructure and texture evolution and thereby on bendability was investigated in an ultrahigh-strength strip steel with a martensitic-bainitic microstructure. The results indicate that an increase in rolling reduction (R _tot) below the non-recrystallization temperature, which improves the strength and toughness properties, increases the intensities of the ~{554}〈225〉 _α and ~{112}〈110〉 _α texture components along the strip centerline and of the ~{112}〈111〉 _α component at the surface region. Even with the highest R _tot of 79 pct, the bendability along the rolling direction was good, but the preferred alignment of rod-shaped MA constituents along the rolling direction led to a dramatic decrease in the bendability transverse to the rolling direction, with severe cracking occurring even at small bending angles. The early cracking is attributed to localization of the strain in narrow shear bands. It is concluded that the R_tot value has to be limited to guarantee successful bendability.     

建筑的工艺

当我几个月前走进奥布兰位于纽约教堂街315号的工作室时,我一下子就被这里工匠作坊般的氛围打动了.用各种材料制作的无数工作模型,从和火柴盒一样小的到巨大的结构、室内和细部研究模型.这些模型立刻说明了他们认真的、实体的、亲密的方法,与当今建筑事务所普遍的诊所般的气氛——更像是律师事务所,而不是一个有人和生活参与的工作场所——大相径庭.奥布兰建筑设计事务所反映了个人的奉献,和对建筑艺术的实质的深厚兴趣,而不是仅仅将设计视为一种职业服务.和奥布兰的建筑师聊天,阅读他们的文字让我理解到对于他们来说建筑创作是一种个人自省的方式,一种培养他们自己个性和世界观的方法.正如路德维希·维特根斯坦所述:"建筑和哲学相似,他们都是人们用来影响自己的方式,针对看待事物的方式."     

Characterization of UHF RFID tags fabricated directly on convex surfaces by pad printing

The possibility of pad printing in RFID tag antenna manufacturing is investigated. Passive UHF RFID tags were printed on flat and on convex surfaces with two different polymer thick-film silver inks. The effect of the ink and substrate material properties on tag antenna performance was examined. The goal was to provide information which is needed in adapting the pad-printing technique in RFID tag manufacture. The results show that pad printing is suitable for tag manufacturing on flat and on convex surfaces. The curvature of the substrate did not significantly affect the tag performance. It was more important to take into consideration other substrate properties, ink characteristics, morphology, and printing parameters. The best practice is to take these matters into consideration in the initial tag design process to ensure proper tag performance at the desired frequency.     

Effect of chemical modification of oil fly ash and compatibilization on the rheological and morphological properties of low‐density polyethylene composites

In this study, the effect of oil fly ash (OFA), a by‐product of oil fuel power plants, on the rheological and morphological behavior of low‐density polyethylene (LDPE) is investigated. As received and acid‐functionalized OFA (COOH‐OFA) are used to examine the effect of surface modification of OFA on polymer–filler composites. LDPE/OFA composites were prepared by melt mixing with filler loading in the range 1–10 wt %. The results are compared with pure LDPE. The effect of polyethylene‐grafted‐maleic anhydride (PE‐g‐MA) as a compatibilizer was also studied. Both viscous and elastic properties of composites increased with OFA loading especially at low frequency. The surface modification of OFA has influenced the properties of OFA. As‐received OFA showed some agglomeration at high loading that resulted in two‐phase system as described by scanning electron microscopy (SEM) and Cole–Cole plot. Field emission‐SEM (FE‐SEM) images showed improvement in the dispersion of COOH‐LDPE/OFA composites. In addition, the surface modification reduced the size of agglomeration. In general, the COOH modification of OFA improved both the dispersion and rheological properties of OFA. With chemical modification, the concentration of the filler can be increased to 10% without compromising the properties of the composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.     

A Model for Chlorine Dioxide Delignification of Chemical Pulp

Abstract

A phenomenon based model for chlorine dioxide delignification of chemical pulp is introduced. The pulp suspension environment is modeled using the concept of two liquid phases, one inside and the other external to the fiber wall. Physico-chemical processes taking place during delignification are implemented with thermodynamic, mass transfer and reaction kinetic models. A broad library of chemical reactions is introduced. Inclusion of each reaction is justified. The model response is tested against experimental laboratory delignification results (o-delignified birch pulp). The experimental data consists of kappa number, hexenuronic acid, inorganic oxy-chlorine compound, and organochlorine (AOX, OX) measurements at several time points during five delignification experiments. The model predictions are mainly in good agreement with the experimental results. The predictions regarding hypochlorous acid driven processes (HexA removal, organochlorine formation, chlorite and chlorate concentration) are somewhat incoherent, indicating that knowledge regarding the intermediately formed hypochlorous acid is presently insufficient.