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Against the background of climate protection and the rising costs of a fossil-fuel-based energy supply, the interest in the energy performance and indoor climate of buildings in real operation is rising. This paper, therefore, deals with the indoor climate investigation of two medium-sized office buildings in Germany by taking measurements over a whole year. These relate to one new building and one refurbished building. Sensors of various types were installed and operated in a large number of office rooms, so that in total results are available for over 100 rooms, typically occupied by one or two persons. The analysis focuses on the indoor temperature in summer and the air quality in winter based on the CO2 concentration. The comfort classes according to DIN EN 16798 including the adaptive comfort approach are used as a basis to cluster the results. Both buildings have movable sun protection and openable windows but no facilities for active cooling. They, thus, represent a large number of existing 'low tech' office buildings in Germany and central Europe. The results reflect the respective building concepts but also show a wide range between the rooms due to the user preferences and behaviour. The refurbished building shows better results, especially in terms of air quality but also in terms of summer room temperatures. This underlines the benefit of the targeted measures as a result of an analysis of the deficits in the existing building before the refurbishment. The additional measures for decentralised mechanical ventilation and passive cooling are having positive effects. As part of the projects, further measures to improve the indoor climate were investigated in both buildings. In one case, this involved CO2 traffic lights to stimulate personal window ventilation in winter, and in the other, the use of newly developed individual ceiling fans supports convective heat dissipation on the human body during hot spells in summer. The positive effect could be demonstrated for both measures. [ABSTRACT FROM AUTHOR]

Decentral monitoring as a contribution towards improving indoor comfort and operation of commercial buildings Many existing non‐residential buildings offer potential for improving the indoor climate and energy performance through improved use and operational management. To do this, however, the conditions must first be measured and assessed so that recommendations for action can be developed. Existing building automation systems are often not sufficiently qualified for these activities. A corresponding expansion of the hardware and/or software is often economically disproportionate. Against this background, room climate measurements were carried out in exemplary buildings with decentralised data loggers of different designs over at least one year. The three buildings selected for this paper have very different ventilation concepts. The two buildings without air conditioning systems showed the influence of user behaviour on the achieved indoor climate level in different ways. The building with an air‐handling system exemplified the influence of an unfavourable set point on energy consumption. Decentralised measurement technology offers great potential for quality assurance in existing buildings. In new buildings, it is necessary to design building automation systems for quality assurance tasks and not only for function assurance. [ABSTRACT FROM AUTHOR]

From 1698, colonial officers and investors from France forged a conglomerate of companies for transforming Saint-Domingue into a sugar colony, thus augmenting incomes of tax farmers and of the crown. Capital was also captured from enemy colonies and generated through trade with Spanish possessions. The most important capital were slaves, both as laborers and mortgageable property—crucial during the War of Spanish Succession, which brought price volatility and speculation in land and sugar. In order to secure the colony's development, authorities restricted rights of owners over their slaves, preventing their sale or abuse. Only around 1715 was such protection of slaves suppressed. [ABSTRACT FROM AUTHOR]

Diese Artikelserie stellt den Einsatz von Computerprogrammen in der Hochschullehre der Bauphysik und Gebäudetechnik für Architekten und Bauingenieure vor. In diesem Beitrag werden die Motivation zur Artikelserie und die Ergebnisse einer Online‐Umfrage an die Lehrenden der deutschsprachigen Hochschulen, initiiert und durchgeführt vom Fachgebiet Bauphysik und Technische Gebäudeausrüstung der Universität Wuppertal, aufgeführt. [ABSTRACT FROM AUTHOR]

The Solar Decathlon is a competition for universities from all over the world which focuses on designing, building and operating experimental, solar-powered houses. Participating in the project offers universities a unique and interdisciplinary platform for teaching, learning and research which combines practical experience with research. In 2022, the European edition was held in Germany for the first time. The event took place with a new urban profile to increase both the relevance of the competition and the learning experience. Its main topic was the further development of the European city, and specifically focused on the existing stock of residential apartment buildings. A total of 18 teams from 11 countries with over 500 students took part, with 16 teams ultimately building their houses on a shared solar campus. Demonstrating a balanced or a positive energy balance in practice was one of the essential goals of the competition. This was achieved by 13 of 15 projects in the energy contest. The prerequisites for this were a high level of energy efficiency and the consistent use of solar energy. Both strategies were embedded in convincing architectural concepts. These ranged from the minimised visibility of standard systems on rooftops, through to custom-built systems with full architectural integration in façades. Hybrid solar systems also became a focus, with the goal of making optimum use of the surfaces on the building envelope. This paper focuses on the energy engineering and technical and architectural integration of the solar systems. It also includes the results achieved in the competition linked to the learning experience. [ABSTRACT FROM AUTHOR]

In this study we present the development of an injectable polymeric drug delivery system for subconjunctival treatment of primary open angle glaucoma. The system consists of hyaluronic acid sodium salt (HA), which is commonly used in ophthalmology in anterior segment surgery, and an isocyanate-functionalized 1,2-ethylene glycol bis(dilactic acid) (ELA-NCO). The polymer mixtures with different ratios of HA to ELA-NCO (1/1, 1/4, and 1/10 (v/v)) were investigated for biocompatibility, degradation behavior and applicability as a sustained release system. For the latter, the lipophilic latanoprost ester pro-drug (LA) was incorporated into the HA/ELA-NCO system. In vitro , a sustained LA release over a period of about 60 days was achieved. In cell culture experiments, the HA/ELA-NCO (1/1, (v/v)) system was proven to be biocompatible for human and rabbit Tenon's fibroblasts. Examination of in vitro degradation behavior revealed a total mass loss of more than 60% during the observation period of 26 weeks. In vivo , LA was continuously released for 152 days into rabbit aqueous humor and serum. Histological investigations revealed a marked leuko-lymphocytic infiltration soon after subconjunctival injection. Thereafter, the initial tissue reaction declined concomitantly with a continuous degradation of the polymer, which was completed after 10 months. Our study demonstrates the suitability of the polymer resulting from the reaction of HA with ELA-NCO as an injectable local drug delivery system for glaucoma therapy, combining biocompatibility and biodegradability with prolonged drug release. [ABSTRACT FROM AUTHOR]

• The Solar Decathlon successfully tackles the triple: design, build, operate. • Competition houses demonstrate net energy positive buildings. • All energy supply systems are based on PV and air heat pumps. • Houses with battery storage provide flexibility in building grid interaction. • Online knowledge platform provides building information and monitoring data. • The competition format can be linked to building science. The Solar Decathlon is a competition for universities from all over the world to design, build and operate small experimental solar powered houses. Its first edition took place in the US in 2002. Since 2010 it is in practice in Europe with four competitions and 65 net zero or net energy plus houses build and tested in 10 disciplines (decathlon). This paper provides an overview and analysis on the European edition of the competition. The work was carried out within the framework of Annex 74 "Competition and Living Lab Platform" of the International Energy Agency and an EC funded project named "Solar Decathlon Europe - Analysis of the Results". The analysis was based on the development of a web based knowledge platform, providing a large set of information and monitored data from past competitions. Based on the availability of information and data, the comparative evaluation is centred on the building energy supply systems and their performance. Starting with very large PV systems, the latest competitions rules trigger the teams to apply systems sized comparable to small buildings in net zero energy building practice. As a result not all houses succeed in a positive energy balance. Due to the wider introduction of batteries the self-consumption of the solar yield and the degree of self-sufficiency increases. New developments of the competition rules stimulate the energy flexibility in operation with the power grid. Modifications for the rules and the monitoring procedure for the next edition intend to further link the competition to building science. [ABSTRACT FROM AUTHOR]

Im Zuge der Erforschung des Klimawandels sind die Prognosemodelle in den letzten Jahren soweit verbessert worden, dass lokale und regionale Klimadatensätze für die Anwendung in Energieberechnungsverfahren für Gebäude vorliegen. Der Beitrag analysiert die Datensätze aus den aktuell verfügbaren Quellen und stellt die relevanten Charakteristika gegenüber. Mit Simulationsrechnungen anhand von drei Nichtwohngebäuden (Büro, Schule, Hotel) wird aufgezeigt, wie sich die Klimadaten auf den Energiebedarf, den Leistungsbedarf und den thermischen Komfort auswirken, sofern keinerlei Anpassungen bei der Baukonstruktion, der Anlagentechnik oder dem Nutzerverhalten erfolgen. Einem deutlich sinkenden Heizwärmebedarf steht bis 2050 eine Zunahme der sommerlichen Raumtemperaturen bzw. des Kältebedarfs gegenüber. Die sommerliche Situation wird insbesondere für Bürobauten kritisch, so dass technische Anlagen zur Kühlung in den sommerheißen Regionen erforderlich werden. Dieser Trend wurde bereits in den vergangenen Jahren beobachtet. Während es für Neubauten dazu energieeffiziente Lösungen gibt, ist die Entwicklung für Bestandsgebäude kritisch. Hier sind wesentliche Verbesserungen von Sonnenschutz und Lüftungsstrategien erforderlich. Für Schulen und Hotels fallen die zu erwartenden Veränderungen vergleichsweise moderat aus. Climate data and climate change - Analysis of the influence on energy demand, performance requirement and thermal comfort of buildings. Continuous research on climate change has improved the knowledge on climate forecast modelling, so that local and regional climate data sets for the application in building energy modelling are available. The paper analyses the data sets of most known sources and compares the relevant characteristics at four German locations. Simulation results for three commercial building examples (office, school and hotel) illustrate how the climate change may influence heating and cooling demands and capacities as well as the summer thermal comfort if no adjustments with respect to construction, service technology and user behaviour are applied. A significant decrease in space heating demand is contrasted by increased cooling demand and increased indoor temperatures during summer even until 2050. Especially for the office buildings, the summer conditions develop critical, so that active cooling will be mandatory in the summer hot regions. This trend was already detected during the past decade. The forecast is critical for all existing buildings. Significant improvements of the envelope properties such as glazing or shading and passive cooling options become mandatory. The changes predicted for schools and hotels remain moderate. [ABSTRACT FROM AUTHOR]

Background and Aims The release of hydrogen cyanide (HCN) from injured plant tissue affects multiple ecological interactions. Plant-derived HCN can act as a defence against herbivores and also plays an important role in plant–pathogen interactions. Crucial for activity as a feeding deterrent is the amount of HCN generated per unit time, referred to as cyanogenic capacity (HCNc). Strong intraspecific variation in HCNc has been observed among cyanogenic plants. This variation, in addition to genotypic variability (e.g. in Trifolium repens), can result from modifications in the expression level of the enzymes involved in either cyanogenic precursor formation or HCN release (as seen in Sorghum bicolor and Phaseolus lunatus). Thus, a modification or modulation of HCNc in reaction to the environment can only be achieved from one to the next generation when under genetic control and within days or hours when transcriptional regulations are involved. In the present study, it is shown that in rubber tree (Hevea brasiliensis) HCNc is modulated by post-translational activity regulation of the key enzymes for cyanide release. Methods Linamarase (LIN) and hydroxynitrile lyase (HNL) activity was determined by colorimetric assays utilizing dissociation of the substrates p-nitrophenyl-β-d-glucopyranoside and acetone cyanohydrin, respectively. Key Results In rubber tree leaves, LIN and HNL show up to ten-fold increased activity in response to tissue damage. This enzyme activation occurs within seconds and results in accelerated HCN formation. It is restricted to the damaged leaf area and depends on the severity of tissue damage. Conclusions LIN and HNL activation (in contrast to genetic and transcriptional regulations) allows an immediate, local and damage type-dependent modulation of the cyanogenic response. Accordingly, this post-translational activation plays a decisive role in the defence of H. brasiliensis against herbivores as well as pathogens and may allow more flexible reactions in response to these different antagonists. [ABSTRACT FROM AUTHOR]

Abstract: To gain access to information on energy use in office buildings, the German Federal Ministry for Economy launched an intensive research and demonstration programme in 1995. In advance of the 2002 EU energy performance directive a limited primary energy coefficient of about 100kWhm−2 a−1 as a goal for the complete building services technology was postulated (HVAC+lighting) for all demonstration buildings to be supported. A further condition was that active cooling be avoided. Techniques such as natural or mechanical night ventilation or heat removal by slab cooling with vertical ground pipes as well as earth-to-air heat exchangers in the ventilation system were applied. An accompanying research was established to keep track of the results and the lessons learned from about 22 demonstration buildings realized and monitored until the end of 2005. As one outcome this paper summarises the energy performance of a selection of characteristic buildings together with an overview on the summer thermal comfort situations achieved. The research program will proceed during the next five years. Detailed reports and future results may be downloaded from the internet: www.enbau-monitor.de. [Copyright &y& Elsevier]

Ceiling fans allow an increase of the local air velocity on the human body. The associated heat transfer increases user's temperature tolerance in warm environments. In the presented study, the differences in the application of statistical turbulence models (RANS) for modelling the air flow induced by a ceiling integrated fan is outlined with particular focus on comparing steady and transient simulations. Results of a CFD simulation (Fluent) are shown and compared with measured data of the horizontal velocity distribution. The study shows that especially the transient simulation using the Realizable k‐ε model shows a stable convergence behaviour regarding the residuals as well as target values. But at 1.1 m above the floor, the mean absolute error of the transient simulation is larger compared to the stationary model using the Multiple Reference Frame (MRF) approach. Despite the stationary model produces an unrealistic velocity distribution in the immediate vicinity of the fan, if the moving zone needs to be small due to obstacles. For a freely suspended ceiling fan, the moving zone can be adjusted accordingly and the flow pattern can be improved. But modelling a ceiling integrated fan with a fan housing and obstacles in the near region, transient simulations using rigid body motion are required for accurate results. [ABSTRACT FROM AUTHOR]

In‐situ measurement of massive building components – Part 1: Comparison of test methods and influences in heating chamber tests In‐situ U‐value measurements are suitable for opaque constructions where a non‐destructive testing of thermal properties is required, e.g. for renovation. In‐situ U‐value measurements are the subject of two research projects from Germany and Switzerland. This Part 1 presents results of the project "LivingLab – Building Performance" at the University of Wuppertal. The aim is to investigate influences on in‐situ U‐value measurement methods for masonry structures in a hot box. It is shown, that in heat flux methods with long measurement periods, size of the heat flux plates and their positioning with respect to mortar joints do not show measurable differences. For uninsulated constructions, this method tends to show lower U‐values, for insulated constructions higher U‐values than calculated. In comparison, short‐term measurements are performed using so‐called "Rapid‐U‐Value Technique (Rapid‐U)". Larger scattering of the results and higher U‐values than with the heat flow method are shown. In Part 2, a research project from Switzerland is presented, in the context of which a practice‐oriented application aid for in‐situ U‐value measurement is being developed. In‐situ U‐value measurements using three different instruments and comparative measurements in the laboratory serve as a basis. [ABSTRACT FROM AUTHOR]

Given the global energy and environmental situation, the European Union has been issuing directives with increasingly demanding requirements in term of the energy efficiency in buildings. The international competition of sustainable houses, Solar Decathlon Europe (SDE), is aligned with these European objectives. SDE houses are low energy solar buildings that must reach the near to zero energy houses’ goal. In the 2012 edition, in order to emphasize its significance, the Energy Efficiency Contest was added. SDE houses’ interior comfort, functioning and energy performance is monitored. The monitoring data can give an idea about the efficiency of the houses. However, a jury comprised by international experts is responsible for carrying out the houses energy efficiency evaluation. Passive strategies and houses services are analyzed. Additionally, the jury's assessment has been compared with the behavior of the houses during the monitoring period. Comparative studies make emphasis on the energy aspects, houses functioning and their interior comfort. Conclusions include thoughts related with the evaluation process, the results of the comparative studies and suggestions for the next competitions. [ABSTRACT FROM AUTHOR]

Abstract: The term Net ZEB, Net Zero Energy Building, indicates a building connected to the energy grids. It is recognized that the sole satisfaction of an annual balance is not sufficient to fully characterize Net ZEBs and the interaction between buildings and energy grids need to be addressed. It is also recognized that different definitions are possible, in accordance with a country''s political targets and specific conditions. This paper presents a consistent framework for setting Net ZEB definitions. Evaluation of the criteria in the definition framework and selection of the related options becomes a methodology to set Net ZEB definitions in a systematic way. The balance concept is central in the definition framework and two major types of balance are identified, namely the import/export balance and the load/generation balance. As compromise between the two a simplified monthly net balance is also described. Concerning the temporal energy match, two major characteristics are described to reflect a Net ZEB''s ability to match its own load by on-site generation and to work beneficially with respect to the needs of the local grids. Possible indicators are presented and the concept of grid interaction flexibility is introduced as a desirable target in the building energy design. [Copyright &y& Elsevier]

[image omitted] Modification of Beller's palladium-catalyzed cyanation procedure leads to a versatile and rapid route to poly-nitrile aromatics via easily available aryl bromides that improve on known literature methods. All cyanide ions on the iron(II) center of the nontoxic cyanide source [potassium hexacyanoferrate(II)] can be transferred to the aryl halide using palladium(II) acetate and 1,1'-bis(diphenylphosphino)ferrocen (dppf). [ABSTRACT FROM AUTHOR]

Abstract: DNA hybridization plays an important role in medical diagnostics, drug development and biological threat discovery. Despite the wide use of optical hybridization detection, electrochemical methods, and especially covalently attached redox markers, attain an increasing interest. However, one problem is that the number of suppliers of electrochemically labelled oligonucleotides is very limited. This paper reports about the use of the commercially available fluorescence quenching label dabcyl (p-methyl red) as a redox active DNA-marker. We investigated the polarographic, voltammetric and adsorptive stripping voltammetric behaviour of this compound in a TRIS buffer at pH 7.5 and found that two polarographic waves (at −0.48 and −1.28V vs. Ag/AgCl) can be easily distinguished compared to only one clear signal between −0.4 and −0.7V in most voltammetric techniques. The alternating-current voltammetric (ACV) signal of a dabcyl-labelled target at a thiollinker-probe-SAM modified gold disk electrode was very clear but small due to a fast and irreversible decay of the reduction product. Despite of this, non-complementary DNA-strands could be discriminated and at 15min hybridization time, trace amounts down to 50nM target concentration could be detected. Such electrochemical use of optically active labels could open new possibilities for spectroelectrochemical studies of DNA hybridization. [Copyright &y& Elsevier]

This study examines the use of tetrahedral [E(O-C6X4-CN)4]- anions (E = B, Al; X = H, F), which can be synthesized from the reaction of tetrahedral NaBH4/LiAlH4 and HO-C6X4-CN, as anionic linkers for the generation of 2D and 3D crystalline coordination polymer networks. Such polymer networks were obtained by the connection of tetrahedral p-cyanophenoxy aluminate or borate linkers with monocationic metal centers such as Li+, Na+, Ag+, and Cu+. These studies are specifically focused on the synthesis, structure, and stability of such polymers. Additionally, the perfluorinated O-C6F4-CN linker was used to study electronic influences. Salts bearing the perfluorinated [E(O-C6F4-CN)4]- anion decompose into E(O-C6F4-CN)3 and [O-C6F4-CN]-, which is also observed when a Lewis acid such as B(C6F5)3 is added. Moreover, addition of B(C6F5)3 leads to the formation of molecular-ion pairs because the cyano groups are now either completely or partly blocked. The structures of M[Al(O-C6H4-CN)4] (M = Li, Ag, Cu), Na[B(O-C6H4-CN)4], and Li[Al(O-C6F4-CN)4] as well as of the decomposition products Na(O-C6F4-CN), (THF)Al[O-C6H4-CN ·B(C6F5)3]3 (THF = tetrahydrofuran), Na[(F5C6)3B ·O-C6H4-CN ·B(C6F5)3], and Li[NC-C6F4-O-Al{O-C6F4-CN ·B(C6F5)3}3] are discussed. [ABSTRACT FROM AUTHOR]

The addition of alkali or silver salts of dicyanoamide (dca), tricyanomethanide (1cm) and tetracyanoborate (tcb) to a solution of B(C6F5)3 in diethyl ether affords salts containing very voluminous B(C6F5)3 adduct anions of the type [E(CN)n-]·[ B(C6F5)3]n: E = N (dca•nb with n 1, 2; b = B(C6F5)3); E = C (tcm•nb with n = 1, 2, 3), and E = B (tcb•nb with n = 1, 2, 3, 4). Salts bearing these anions such as B[(CN)·B(C6F5)3]4- (= [B(CN)4]·[ B(C6F5)3]4), C[(CN)·B(C6F5)3]3- (= [C(CN)3-]·[ B(C6F5)3]3), and N[(CN)·B(C6F5)3]2- (=[N(CN)2-]·[ B(C6F5)3]2) can be prepared in good yields. They are thermally stable up to over 200 °C and dissolve in polar organic solvents. Depending on the stoichiometry mono-, di-, tri-, or tetraadduct formation is observed. The solid state structures of dca•2b, tcm•3b and tcb•4b salts show only long cation⋯anion contacts and thereby weak interactions, large anion volumes and only small distortions of the dca, tcm or tcb core enwrapped between B(C6F5)3 groups. That is why these anions can be regarded as weakly coordinating anions. On the basis of B3LYP/6-31 +3(d) computations the energetics, structural trends and charge transfer of the adduct anion formation were studied. Since tcm•3b and tcb•4b are easily accessible and can also be prepared in large quantities, these anions may be utilized as a true alternative to other widely used weakly coordinating anions. Moreover, for both steric and electronic reasons it seems reasonable to expect that as counterions for cationic early transition metal catalysts such anions may show reduced ion pairing and hence increased catalytic activity. [ABSTRACT FROM AUTHOR]