The Story of An Intersection,or How Early Chicago Became an Urban Laboratory

This essay unravels the history of Chicago as an urban laboratory and the way crisis was utilised and even staged in order to project alternative scenarios. It centres on a single photograph of an intersection from 1909, which shows the location saturated with a shocking amount of traffic brought to a standstill. To make visible what commonly remained hidden (the flows and intensities of urban movement), city officials had administered an urban experiment that suspended police presence and regulation in an effort to test if the metropolis could still self-regulate. Using the city as a stage for experimentation that at times pushed it to the brink of collapse, Chicago’s officials perceived their town as an urban test-bed. Injecting this reading into our established historiography reconfigures some of its most prominent narratives: from Sullivan’s Kindergarten Chats, and Burnham and Bennett’s Plan for the city, to the Chicago school of sociology.     

Strategies of the Bulgarian vernacular: continuity in Bulgarian house design from National Revival times to the present day

The starting point of the article is the Bulgarian ‘National Revival House’ as it represents the most noteworthy product of Bulgarian vernacular architecture. It also demonstrates the meeting of European and West Asian building traditions: based on the Ottoman dwelling, the Bulgarian house shows an adaptation of the former to Christian Balkan living as well as the impact of various outside influences from the Ottoman Baroque to Central European models.

The examples date from the late eighteenth century to the present day, with an emphasis on the second half of the nineteenth century. They are encountered in rural, small-town and urban environments and exhibit a remarkable degree of basic uniformity of design: assemblage, lightness, cleanness of form and increasing monumentality are the most abiding characteristics of the Bulgarian ‘National Revival house’.

The thrust of this study is not so much towards a theoretical definition of the Bulgarian vernacular but more the analysis of the dominant architectural strategies in the design of domestic structures. After identifying the principal formal characteristics of the Bulgarian vernacular house, the aim is to demonstrate the continuity of those strategies into the modern period and to the present day. For this purpose, not only well-documented landmark buildings of the inter-War and Communist periods but also little-known examples will be considered. This will serve to establish the idea of a continuous Bulgarian vernacular as the common architecture of the people of Bulgaria.     

The distribution, abundance and diversity of birds in Manila's last greenspaces

Urban environments are not considered areas with conservation importance. However greenspaces in cities have been previously identified as areas with significant avian biodiversity. We investigated the distribution and diversity of birds in what are increasingly considered as Metropolitan Manila's last greenspaces; the University of the Philippines campus, military cemeteries and two government operated parks. Using species–area analysis, abundance and diversity indices, TWINSPAN ordination and logistic regression to determine important landscape features for species presence, we describe the distribution of bird communities and diversity in Metropolitan Manila. Two major bird community groupings were observed. These are the urban exploiters and the urban adaptable with the former occurring in high abundances and the latter in low abundances in greenspaces. The number of built and natural spatial entities determines abundances. Species area analysis suggests that the greenspaces are distinct habitats that preserve faunal uniqueness whereas urbanization tends to decrease diversity. These observations suggest that greenspaces harbor significant avian biodiversity as well as the presence of endemic and threatened species. As the greenspaces possess remnant wetland and wooded habitat we recommend that they be preserved and maintained by ensuring that these habitats are incorporated in any urban development plan.     

Zur Querkraftgefährdung bestehender Spannbetonbrücken

Zur Formulierung einer Handlungsanweisung werden in Teil I die geänderten Lastannahmen für Brücken nach DIN Fachbericht 101 mit den Belastungsklassen nach alten Normen verglichen und gezeigt, wie anhand aktueller Verkehrszahlen die Lastansätze modifiziert werden können. Der aktuelle Brückenbestand in Hessen wird mit der Straßeninformationsbank (Teilprojekt Bauwerksdaten) ausgewertet, um Klassifizierungs‐ und Bewertungskriterien zu erarbeiten. Zur Beurteilung des Querkraftwiderstandes werden die Grundlagen der Querkraftbemessung nach DIN 1045, DIN 4227, DIN Fachbericht 102 und aus der Literatur gegenübergestellt. Shear‐Vulnerability of Existing Pre‐Stressed Concrete Bridges. Part One: Basics In Part I, to formulate an operation directive the revised load assumptions for bridges of DIN Technical Report 101 are compared with the loading classes according to old standards and it is demonstrated, how the loading models can be modified based on actual traffic data. The current bridge asset in the Federal State of Hesse is evaluated using the “Road Information Database (Sub‐Project: Structural Data)” in order to work out classification and evaluation criteria. Regarding the assessment of the shear load‐bearing capacity the fundamentals of the shear load design models of DIN 1045, DIN 4227, DIN TR 102 and from the literature are compared.     

An Improved Approach for 3D Rolling Contact Fatigue Simulations with Microstructure Topology

Several 2D and 3D numerical models have been developed to investigate rolling contact fatigue (RCF) by employing a continuum damage mechanics approach coupled with an explicit representation of microstructure topology. However, the previous 3D models require significant computational effort compared to 2D models. This work presents a new approach wherein efficient computational strategies are implemented to accelerate the 3D RCF simulation. In order to reduce computational time, only the volume that is critically stressed during a rolling pass is modeled with an explicit representation of microstructure topology. Furthermore, discontinuities in the subsurface stress calculation in the previously developed models for line and circular contact loading are removed. Additionally, by incorporating a new integration algorithm for damage growth, the fatigue damage simulations under line contact are accelerated by a factor of nearly 13. The variation in fatigue lives and progression of simulated fatigue spalling under line contact obtained using the new model were similar to the previous model predictions and consistent with empirical observations. The model was then extended to incorporate elastic–plastic material behavior and used to investigate the effect of material plasticity on subsurface stress distribution and shear stress–strain behavior during repeated rolling Hertzian line contact. It is demonstrated that the computational improvements for reduced solution time and enhanced accuracy are indispensable in order to conduct investigations on the effects of advanced material behavior on RCF, such as plasticity.     

HPLC法测定联苯乙酸巴布剂中药物含量及其体外透皮性能的研究

目的:建立联苯乙酸巴布剂中联苯乙酸含量的HPLC测定方法,研究联苯乙酸巴布剂(LDH-Cata-plasm)的体外透皮释放性能,并与国外商品样品(J-Cataplasm)进行了比较。方法:高效液相色谱法,色谱柱:Wa-ters SunFireC18柱(150mm×4.6mm,5μm);流动相:甲醇-乙酸铵水溶液(60?40)(乙酸调节pH=3.6);流速:1.0mL/min,检测波长:254nm,进样量:10μL。用离体豚鼠皮肤作为透皮屏障,采用改进的Franz扩散池测定联苯乙酸巴布剂的体外透皮性能。结果:在1.26～20.16μg/mL浓度范围内,联苯乙酸浓度与峰面积之间呈良好线性关系,相关系数r=0.9999;定量限为0.05μg/mL;回收率为98.7%～100.0%。LDH-Cataplasm与J-Cataplasm的体外透皮方程均符合Higuchi方程(Q=kt1/2),且两者的体外透皮过程相似,各时间点的透皮速率无显著性差异。结论:该方法快速、简便,重复性好,可用于联苯乙酸巴布剂的含量测定及其体外透皮释放量的测定。     

Nanotribology of Confined Water by Quasistatic Computer Simulations: Effect of Impurities

In our previous simulation study (Pertsin and Grunze, Langmuir 24:4750–4755, 2008), we have shown that water bilayer films confined between structured hydrophilic substrates can acquire the ability to sustain shear stress (i.e., to solidify), while remaining fluidlike in respect of the lateral order and molecular mobility. In this article, the previous simulations are extended to aqueous bilayer films containing simple model impurities. The shear behavior of the films is studied using the grand canonical Monte Carlo technique and quasistatic approach. It is found that the impurities tend to separate into an individual phase or to dissolve in water depending on the strength of the water–impurity interaction. In the former case, the effect of impurity on the shear modulus and yield stress is moderate and nearly linear in the concentration of impurity. In the latter case, the effect is noticeably stronger because the impurity distorts the local order and arrangement of water molecules, thus disturbing the local epitaxial coupling between the aqueous film and confining substrates. At the highest impurity content tried (~13%), the aqueous film loses most of its solidity and becomes practically fluidlike in respect to the shear response.     

Automatic Absorbance Calibration Routine for a Computerized Uv-Visible Rapid Scanning Spectrophotometer

Sir:

A Fortran IV computer program is used to calculate absorbance at varying wavelengths in a UV-visible rapid scanning spectrophotometer. Using the program eliminates the necessity of calibrating the absorbance axis in the usual manner using standard solutions or filters and plotting calibration curves, because the voltage output of the computer is automatically identical to the actual absorbance of a sample.     

Structures and electronic properties of surface/edges of nanodiamond and nanographite

The structure, electronic and magnetic properties of nanodiamond and nanographite/nanographene are investigated. Detonation nanodiamond particles that are covered with amorphous graphitic composites are hydrothermally treated to remove the graphitic surface composites and to terminate the surface carbon atoms with hydrogen. The number of localized spins of dangling bonds and the hydrogen concentration increase upon the increase in the hydrothermal treatment time up to 40 h. Above 40 h, both drop discontinuously, a surface structural reconstruction was suggested. The creation of dangling bonds and an incomplete hydrogenation of the surface carbon atoms destabilize the surface, resulting in the structural reconstruction. Nanodiamond particles are thermally converted to nanographite/nanographene. A single nanographene sheet is successfully prepared by heat-treating nanodiamond particles. The edge of graphene sheet with its edge carbon atoms being hydrogen-terminated is investigated by UHV-STM/STS. Zigzag edges are found to have non-bonding π-state of edge origin, in good agreement with theoretical prediction.