Understanding the Hobrecht Plan. Origin,composition, and implementation of urban design elements in the Berlin expansion plan from 1862

ABSTRACT

The nineteenth-century master plans for European cities influence their development beyond their intended lifespans and provide a variety of robust urban fabrics to this day. The Hobrecht Plan for Berlin's urban expansion (1862) was intentionally conceived to adapt to an uncertain future, remaining influential even today. For a considerable time, the Hobrecht Plan was disregarded and considered irrelevant across the spectrum of development plans in Europe. This article presents a comprehensive re-assessment of the Hobrecht Plan with an emphasis on its intrinsic value. The plan defined a new set of urban patterns, forms and spaces in 15 section plans and a range of public space typologies defining Berlin's cityscape. The plan developed a spatial and structural framework using three different urban design elements: the ring boulevard, the harbour square, and the neighbourhood square. These key organizing elements have helped public spaces remain the effective planning units of Berlin's neighbourhoods. This analysis provides insight on how contemporary master plans can better formulate long-term strategies to address complexity, adaptability, and flexibility. The article presents novel outlooks on Berlin's city structure and new knowledge of Hobrecht's contribution to the planning discipline.     

Total Mercury, Inorganic Mercury and Methyl Mercury Determination in Red Wine

This study deals with the development of a method for total Hg, inorganic Hg and methylmercury (MeHg) determination in red wine by using flow injection-cold vapour generation–inductively coupled plasma mass spectrometry (FI-CVG-ICP-MS) and gas chromatography-ICP-MS (GC-ICP-MS). For Hg speciation analysis, a derivatization step was carried out using a 1% (m/v) sodium tetraphenylborate (NaBPh₄) solution, followed by extraction of Hg species and their quantification by GC-ICP-MS. The main parameters evaluated were the make-up gas flow rate, volume of the NaBPh₄ solution, time for derivatization reaction/analyte extraction and solvent used for Hg species extraction. Accuracy was evaluated by analyte recovery, whereas recoveries ranged from 99% to 104% for Hg(II) and MeHg. The limits of detection (LODs) for Hg(II) and MeHg were 0.77 and 0.80 μg L⁻¹, respectively. Wine from Argentina, Brazil, Chile and Uruguay were analysed. The wine samples were also acid digested for total Hg determination by FI-CVG-ICP-MS. The LOD of the method used for total Hg determination was 0.01 μg L⁻¹. The concentrations of Hg species in red wine measured by GC-ICP-MS were lower than the respective LODs. Only total Hg was detected in the analysed samples, where the highest concentration of Hg found was 0.55 ± 0.02 μg L⁻¹.     

Oil removal from crude oil-in-saline water emulsions using chitosan as biosorbent

ABSTRACT

The sorption of oil from crude oil-in-saline water emulsions was studied using chitosan as biosorbent. The main parameters investigated were chitosan dosage, contact time, and initial crude oil concentration at fixed initial pH. The results showed that the sorption equilibrium was reached within 120 min at oil content as low as 20 mg L^?1. Sorption depends on initial oil concentration and sorbent dosage and may reach up to 95% efficiency in the most favorable conditions. The residual oil concentrations obtained after sorption were always beneath the official limit of oil discharge into environment.     

Systemic congenital lymphangiomatosis

Systemic lymphangiomatosis is a rare disease characterized by the exageration of lymphatic channel proliferation, occurring in children and young adults. We describe an extremely rare case of congenital systemic lymphangiomatosis in a newborn who had ascitis and respiratory failure develop immediately after delivery. Death occurred during the first hour of life. Autopsy findings showed numerous cysts in soft tissues of the cervical area, mediastinum and diaphragm, and several other organs including the liver, spleen, thyroid and kidneys. The severe and diffuse involvement with cysts in both lungs by lymphangiomatosis was associated with poor prognosis and death in our case.     

Chitosan derivatives with thickening properties obtained by reductive alkylation

Chitosan derivatives were prepared by reductive alkylation using glutaraldehyde and 3-amino-1-propanol. The reducing agent used was sodium borohydride. Tests of solubility, stability and viscosity were performed to evaluate the effect of the molar ratio of the reactants and the presence of nitrogen in the reaction system. The ¹H NMR characterization of chitosan derivatives confirmed the presence of hydrophobic groups grafted onto the chitosan backbone. The rheological behavior of the polymers was studied as a function of polymer concentration, temperature and ionic strength of the medium. It was observed that the chemical modification of chitosan resulted in derivatives with thickening action, and the polymer solubility in acetic acid aqueous solution decreased with the increase of the glutaraldehyde and 3-amino-1-propanol molar ratio in relation to chitosan. The atmosphere of nitrogen and a larger amount of reducing agent in the reaction system contributed to the increase in solubility, stability and viscosity of the polymer in solution. The chitosan derivative solutions were significantly more viscous than the chitosan solution and showed higher thermal stability in the presence of salt, which could be explained by the hydrophobic groups grafted onto the chitosan backbone.