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Ein Energiemanagementsystem nach DIN EN ISO 50001 hilft Unternehmen, ihren Energieverbrauch zu erfassen und ihre Energieeffizienz zu verbessern. Da beim Energiemanagement eine große Menge an Daten erhoben und verwaltet werden muss, wird in diesem Beitrag eine Methode vorgestellt, wie relevante Einflussgrößen (Variablen) auf den Energieverbrauch identifiziert und in Leistungskennzahlen berücksichtigt werden können. Die Methode ist konform mit den ISO-Standards 50001 und 50006. Zur Verwaltung der Daten wird ein Prozess-Informationsmodell verwendet, welches weiterhin die Übertragbarkeit der Methode auf verschiedene Produktionssysteme vereinfacht. Die sechs Schritte der Methode werden im Verlauf des Beitrages erläutert und auf einen beispielhaften Anwendungsfall des Zerkleinerungsprozesses von Erz in einer Mine angewendet. So wird gezeigt, wie die Methode zur Verringerung des Energieverbrauchs und der Treibhausgasemissionen beitragen kann.

Mit steigender Energiegewinnung aus erneuerbaren Energien kommt Speichersystemen eine zunehmend wichtige Bedeutung zu. Die notwendigen Planungsfunktionen für den automatisierten, wirtschaftlichen und ökologischen Betrieb von Speichern sind Fokus dieses Beitrags. Zunächst werden diese Funktionen beschrieben, und es werden Anforderungen an sie hergeleitet. In einer Fallstudie wird ein einfaches Beispiel einer Planungsfunktion in Form eines mathematischen Optimierungsmodells verwendet, um Strom möglichst günstig und emissionsarm an der Intraday-Strombörse einzukaufen. Die Kosten und Emissionen des Stromeinkaufes lassen sich durch den Einsatz von Speichern in der betrachteten Fallstudie signifikant reduzieren, wobei sich auch zeigt, dass das Einsparpotenzial für Speicher mit Größen von über vier Betriebsstunden zunehmend abflacht.

A sacrificial film of polystyrene nanoparticles was utilized to introduce nano-cavities in mesoporous metal oxide layers. This enabled the growth of larger perovskite crystals inside the oxide scaffold with significantly suppressed non-radiative recombination and improving device performance. This work exemplifies potential applications of such nanoarchitectonic approaches in perovskite opto-electronic devices., 4 pages

In this work we compare seven different types of natural and synthetic graphite particles and examine how their integration into the cathode of carbon-based perovskite solar cells (C–PSCs) is influencing their opto-electronic properties. By combining x-ray diffraction, Raman spectroscopy and 4-point probe measurements we show that the differences in graphite crystallinity significantly affect the sheet resistance of the carbon-based cathode. The most conductive carbon-based film with an exceptional sheet resistance of 4 Ω/sq. have been produced from scaly graphite with the crystallite dimensions of La = 60.6 nm and Lc = 28.6 nm. Electrochemical Impedance Spectroscopy further revealed that charge transfer resistance at the perovskite/carbon contact differ for each graphite type. Overall, the pyrolytic graphite was found to be the best compromise between high conductivity and low charge transfer resistance leading to least series resistance losses and a fill factor (FF) above 74% (in perovskite solar cells with area of 0.64 cm2). However, an overall efficient hole extraction and lower non-radiative charge recombination in C–PSCs with scaly graphite resulted in the highest average power conversion efficiency and a champion device reaching 14.63%. All the C–PSCs show exceptional moisture stability for 5,000 h under ambient condition, with a PCE decrease of less than 3%.

While perovskite photovoltaic (PV) devices are on the verge of their commercialization, promising methods to recycle or remanufacture fully-encapsulated perovskite solar cells (PSCs) and modules are still missing. Through detailed life-cycle assessment shown in this work, we identify that the majority of the greenhouse gas emissions can be reduced by re-using the glass substrate and parts of the PV cells. Based on these analytical findings, we develop a novel thermally-assisted mechanochemical approach to remove the encapsulants, the electrode and the perovskite absorber, allowing to re-use most of the device constituents for remanufacturing PSCs, which recovered nearly 90% of their initial performance. This remanufacturing strategy allows to save up to 33% of the module’s global warming potential. Finally, we demonstrate that the CO2-footprint of these remanufactured devices can become less than 30g/kWh, which is the value for state-of-the-art c-Si PV modules and can even reach 15g/kWh assuming a similar lifetime

Summary Although it still contributes to less than 2% of the worldwide electricity generation, photovoltaics (PVs) is on the way to becoming a key energy technology for a global future renewable energy infrastructure. We present projections of worldwide CO2 emissions of the future PV industry, finding that these emissions will likely surpass those caused by the global shipping or aviation sector. As an alternative, we propose a fully printed PV reverse manufacturing concept that minimizes the carbon footprint to the ultimate lower limit of the glass substrate fabrication. This so called “in situ” approach is based on a perovskite absorber that is highly durable and encapsulated with glass solder between float glass substrates, reducing the CO2-footprint of conventional PV modules by 1/20th. Yielding a certified stabilized efficiency of 9.3%, this record efficiency for glass-solder-encapsulated perovskite PV paves the way for future solar cells with the lowest carbon footprints.

Determining the effect of defects in fiber-reinforced materials, such as polymer matrix composites (PMCs), can be studied by creating artificial flaws in these materials, for example by introducing artificial PTFE foil to induce material delaminations. For fiber-reinforced ceramics (CMCs), this approach is more difficult due to the more complicated production routes of CMCs, which involve several processing steps at elevated temperatures. This work deals with the fabrication and introduction of defined defects in carbon fiber reinforced silicon carbide (C/C-SiC) composites in a way, which allows their detection by non-destructive material testing methods during and after each production step of the composite. It was shown that the defects produced using boron nitride (BN) and alumina fiber roving were stable over the entire manufacturing process and could be detected by ultrasound and x-ray tomography techniques. To determine any possible effects, an initial sampling of bending samples with artificial defects was manufactured, tested and compared with defect-free reference materials. These tests showed a lower bending strength and failure strain for the defect samples compared to samples without defects.

Carbon-based electrodes have been widely applied in perovskite solar cells (PSCs) because of their chemical inertness and compatibility with up-scalable techniques, signifying their solid potential for mass-production. The material scarcity and complexity of metal ore extraction further highlights that conventionally used noble metal electrodes cannot represent a sustainable option for back-contact in PSCs, while cells with carbon-based electrodes represent an excellent solution to these problems. However, their power conversion efficiencies (PCEs) still lag behind the traditionally processed cells with metal electrodes, resulting in a considerable efficiency gap. To overcome this issue, we propose the use of low-temperature carbon-based (LTCB) electrodes, which offer several key advantages in comparison to mesoscopic high-temperature treated ones: (1) larger choice of selective layers, (2) applicability to all perovskite crystallization methods, (3) compatibility with flexible substrates and (4) faster deposition process. In this review, we analyze numerous techniques to formulate the LTCB-paste and ways to deposit it on the cell stack which have been developed in order to improve the interfacial contact and electrode conductivity. Besides describing the current state-of-the-art perovskite solar cells with LTCB-electrodes, the most promising strategies to enhance the PCE of such photovoltaic (PV) devices are discussed. Overall, we emphasize that PSCs with a LTCB-electrode combine high device stability, low manufacturing costs and low environmental impact, while having options for pushing the efficiency of carbon-based PSCs closer to the record-breaking cells, all of which are vital in order to fulfill the true potential of perovskite PV.

BackgroundIgG4 is associated with two emerging groups of rare diseases: 1) IgG4 autoimmune diseases (IgG4-AID) and 2) IgG4-related diseases (IgG4-RLD). Anti-neuronal IgG4-AID include MuSK myasthenia gravis, LGI1- and Caspr2-encephalitis and autoimmune nodo-/paranodopathies (CNTN1/Caspr1 or NF155 antibodies). IgG4-RLD is a multiorgan disease hallmarked by tissue-destructive fibrotic lesions with lymphocyte and IgG4 plasma cell infiltrates and increased serum IgG4 concentrations. It is unclear whether IgG4-AID and IgG4-RLD share relevant clinical and immunopathological features.MethodsWe collected and analyzed clinical, serological, and histopathological data in 50 patients with anti-neuronal IgG4-AID and 19 patients with IgG4-RLD.ResultsA significantly higher proportion of IgG4-RLD patients had serum IgG4 elevation when compared to IgG4-AID patients (52.63% vs. 16%, p = .004). Moreover, those IgG4-AID patients with elevated IgG4 did not meet the diagnostic criteria of IgG4-RLD, and their autoantibody titers did not correlate with their serum IgG4 concentrations. In addition, patients with IgG4-RLD were negative for anti-neuronal/neuromuscular autoantibodies and among these patients, men showed a significantly higher propensity for IgG4 elevation, when compared to women (p = .005). Last, a kidney biopsy from a patient with autoimmune paranodopathy due to CNTN1/Caspr1-complex IgG4 autoantibodies and concomitant nephrotic syndrome did not show fibrosis or IgG4+ plasma cells, which are diagnostic hallmarks of IgG4-RLD.ConclusionOur observations suggest that anti-neuronal IgG4-AID and IgG4-RLD are most likely distinct disease entities.

One of the main issues hindering the commercialization of perovskite photovoltaics (PV) is device stability. A myriad of various strategies to stabilize the perovskite layer against degradation under continuous illumination has been demonstrated in perovskite community, such as perovskite passivation with 2D perovskites, organic hydrophobic layers, ionic liquids, as well as the deployment of robust inorganic charge transport layers. However, for commercially established PV technologies, the most detrimental degradation occurs in fact under reverse bias. A cell in a module can be placed under reverse bias due to significant current mismatch between series-interconnected cells, which typically happens under operational conditions when shading takes place. Such situation causes the non-shaded solar cells to act as a reverse-bias voltage source on the shaded cell, causing it to operate at high negative voltages, dissipating its energy as heat producing a so-called This phenomenon is commonly known as "hot-spot" degradation and is considered to be one of the most severe degradation mechanisms even in crystalline silicon PV. Concomitantly, only few studies on the reverse bias degradation in perovskite PV devices have been published, revealing that this is a severe source of degradation. Thus, reverse bias degradation presents one of the most fundamental challenges for commercializing not only single-junction perovskite PV modules, but also the ones with tandem configurations. In this work, we demonstrate that perovskite PV devices with mesoscopic scaffold and carbon-based electrode have outstanding resilience against reverse bias degradation and are able to withstand negative voltages up to -9V. The presence of chemically inert carbon electrode, utilization of single-halide mixed-dimensional 2D/3D perovskite and robust inorganic charge transport layers helps to avoid commonly-occurring issues in state-of-the-art cells, like localized -melting of metal electrodes, ion diffusion and halide segregation. Looking more in-depth at the nature of reverse bias degradation in PSCs we demonstrate that the issue of iodine loss still prevails even in such stable devices. Low activation energy of I- vacancies causes an accumulation of charges at the interfaces, resulting in significant bend bending at the interfaces between perovskite and charge-transport layer. Under reverse bias the bending increases until the so-called "breakdown voltage" is reached beyond which holes are able to tunnel through to the valence band of perovskite. This hole-tunneling oxidizes incorporated iodine to create iodine vacancies and thermodynamically favorable iodine compounds, which decompose perovskite structure. Thus, iodine loss can cause device degradation, if it is exposed to reverse-bias for long time durations. For reverse bias voltages exceeding -9V, via thermographic imaging we overserved in-operando formation of hotspots and thermal degradation of perovskite into PbI2. To demonstrate that modules with carbon electrodes would be able to withstand hot-spot conditions, we manufactured modules with carbon back electrodes of 10x10cm2 size and 11.1% power conversion efficiency and subjected them to requirements of IEC61215 hot-spot test at an accredited laboratory Fraunhofer ISE PV Modules Testlab, which has never been done before according to our knowledge. Finally, the modules were able to pass the conditions of the IEC tests for c-Si and thin-film technologies confirming that mesoscopic scaffold and carbon electrodes provide effective stabilization strategy for perovskite PV devices against reverse-bias degradation. (Bogachuk et al. 2021) This work for the first time demonstrates that perovskite-based modules with carbon-based modules can withstand severe reverse bias, which is an essential attribute of this emerging technology on its path towards commercialization.

Carbon-electrode-based perovskite solar cells (C-PSCs) are promising candidates for commercialization due to their high stability. However, the absence of a hole selective layer (HSL) often limits their performance, yielding low fill factors (FFs). Herein, a certified FF of 78.8% obtained through HSL-free C-PSCs is focused. This is found to approach the highest values reported for metal-electrode-based PSCs employing highly selective HSLs. The loss mechanisms affecting the FF in fully printed HSL-free C-PSCs are thus investigated. Methods commonly used to analyze and quantify the impact of recombination and transport losses on the FF of established photovoltage devices are assessed, and their applicability in C-PSCs is examined. In the improved devices, non-radiative recombination contributes to only 3%abs loss with respect to the FF in the radiative limit, which is attributed to an optimal diode ideality factor approaching 1.0. Moreover, contributions of shunt resistive losses are determined to be negligible. Interfacial series resistance losses at the perovskite/carbon interface are identified as the main loss channel, highlighting the importance of the quality of the contact between the perovskite and the back-contact electrode.

Most childhood cancers occur sporadically and cannot be explained by an inherited mutation or an unhealthy lifestyle. However, risk factors might trigger the oncogenic transformation of cells. Among other regulatory signals, hypermethylation of

The photocurrent density-voltage (J(V)) curve is the fundamental characteristic to assess opto-electronic devices, in particular solar cells. However, it only yields information on the performance integrated over the entire active device area. Here, a method to determine a spatially resolved photocurrent image by voltage-dependent photoluminescence microscopy is derived from basic principles. The opportunities and limitations of the approach are studied by the investigation of III-V and perovskite solar cells. This approach allows the real-time assessment of the microscopically resolved local J(V) curve, the steady-state Jsc, as well as transient effects. In addition, the measurement contains information on local charge extraction and interfacial recombination. This facilitates the identification of regions of non-ideal charge extraction in the solar cells and enables to link these to the processing conditions. The proposed technique highlights that, combined with potentiostatic measurements, luminescence microscopy turns out to be a powerful tool for the assessment of performance losses and the improvement of solar cells.

Herein, a simple way of tuning the optical and structural properties of porphyrin‐based hydrogen‐bonded organic frameworks (HOFs) is reported. By inserting transition metal ions into the porphyrin cores of GTUB‐5 (p‐H8‐TPPA (5,10,15,20‐Tetrakis[p‐phenylphosphonic acid] HOF), the authors show that it is possible to generate HOFs with different band gaps, photoluminescence (PL) life times, and textural properties. The band gaps of the resulting HOFs (viz., Cu‐, Ni‐, Pd‐, and Zn‐GTUB‐5) are measured by diffuse reflectance and PL spectroscopy, as well as calculated via DFT, and the PL lifetimes are measured. Across the series, the band gaps vary over a narrow range from 1.37 to 1.62 eV, while the PL lifetimes vary over a wide range from 2.3 to 83 ns. These differences ultimately arise from metal‐induced structural changes, viz., changes in the metal‐to‐nitrogen distances, number of hydrogen bonds, and pore volumes. DFT reveals that the band gaps of Cu‐, Zn‐, and Pd‐ GTUB‐5 are governed by highest occupied/lowest unoccupied crystal orbitals (HOCO/LUCO) composed of π‐ orbitals on the porphyrin linkers, while that of Ni‐GTUB‐5 is governed by a HOCO and LUCO composed of Ni dorbitals. Overall, our findings show that metal‐insertion can be used to optimize HOFs for optoelectronics and small‐molecule capture applications.

Background IgG4 is associated with two emerging groups of rare diseases: 1) IgG4 autoimmune diseases (IgG4-AID) and 2) IgG4-related diseases (IgG4-RLD). Anti-neuronal IgG4-AID include MuSK myasthenia gravis, LGI1- and Caspr2-encephalitis and autoimmune nodo-/paranodopathies (CNTN1/Caspr1 or NF155 antibodies). IgG4-RLD is a multiorgan disease hallmarked by tissue-destructive fibrotic lesions with lymphocyte and IgG4 plasma cell infiltrates and increased serum IgG4 concentrations. It is unclear whether IgG4-AID and IgG4-RLD share relevant clinical and immunopathological features. Methods We collected and analyzed clinical, serological, and histopathological data in 50 patients with anti-neuronal IgG4-AID and 19 patients with IgG4-RLD. Results A significantly higher proportion of IgG4-RLD patients had serum IgG4 elevation when compared to IgG4-AID patients (52.63% vs. 16%, p = .004). Moreover, those IgG4-AID patients with elevated IgG4 did not meet the diagnostic criteria of IgG4-RLD, and their autoantibody titers did not correlate with their serum IgG4 concentrations. In addition, patients with IgG4-RLD were negative for anti-neuronal/neuromuscular autoantibodies and among these patients, men showed a significantly higher propensity for IgG4 elevation, when compared to women (p = .005). Last, a kidney biopsy from a patient with autoimmune paranodopathy due to CNTN1/Caspr1-complex IgG4 autoantibodies and concomitant nephrotic syndrome did not show fibrosis or IgG4+ plasma cells, which are diagnostic hallmarks of IgG4-RLD. Conclusion Our observations suggest that anti-neuronal IgG4-AID and IgG4-RLD are most likely distinct disease entities.

This paper introduces the successful implementation of a fibre-optic sensing system for direct and distributed strain measurement within the shotcrete lining of a conventional tunnel drive. The shotcrete lining of the top-heading and the invert are equipped with two layers (rock side and cavity side) of fibre-optic sensing cables installed in circumferential and longitudinal direction. All cables are measured autonomously for several weeks to capture the strain evolution inside the lining from the day of the construction to a posterior, well-hardened state. An additional follow-up measurement is conducted 2 months afterwards. The measurements enable an assessment of the strain distribution inside the lining with a spatial resolution in the range of some centimetres and a measurement resolution of up to 1 µm/m. Besides the conventional monitoring targets used for displacement recordings, measurement equipment like strain gages and pressure cells are also installed in the cross-section under investigation. Back-calculated strain from absolute displacements and the readings from the strain gages show good agreement with the results of the conducted fibre-optic measurements and verify the suitability of the used system.

Tremendous efforts have been dedicated toward minimizing the open-circuit voltage deficits on perovskite solar cells (PSCs), and the fill factors are still relatively low. This hinders their further application in large scalable modules. Herein, we employ a newly designed ammonium salt, cyclohexylethylammonium iodide (CEAI), for interfacial engineering between the perovskite and hole-transporting layer (HTL), which enhanced the fill factor to 82.6% and consequent PCE of 23.57% on the target device. This can be associated with a reduction of the trap-assisted recombination rate at the 3D perovskite surface, via formation of a 2D perovskite interlayer. Remarkably, the property of the 2D perovskite interlayer along with the cyclohexylethyl group introduced by CEAI treatment also determines a pronounced enhancement in the surface hydrophobicity, leading to an outstanding stability of over 96% remaining efficiency of the passivated devices under maximum power point tracking with one sun illumination under N-2 atmosphere at room temperature after 1500 h.

Herein, the design and synthesis of a highly photoluminescent and electrically conductive metal–organic framework [Zn{Cu‐p‐H6TPPA}]⋅2 [(CH3)2NH] (designated as GTUB3), which is constructed using the 5,10,15,20‐tetrakis [p‐phenylphosphonic acid] porphyrin (p‐H8TPPA) organic linker, is reported. The bandgap of GTUB3 is measured to be 1.45 and 1.48 eV using diffuse reflectance spectroscopy and photoluminescence (PL) spectroscopy, respectively. The PL decay measurement yields a charge carrier lifetime of 40.6 ns. Impedance and DC measurements yield average electrical conductivities of 0.03 and 4 S m−1, respectively, making GTUB3 a rare example of an electrically conductive 3D metal–organic framework. Thermogravimetric analysis reveals that the organic components of GTUB3 are stable up to 400 °C. Finally, its specific surface area and pore volume are calculated to be 622 m2 g−1 and 0.43 cm3 g−1, respectively, using grand canonical Monte Carlo. Owing to its porosity and high electrical conductivity, GTUB3 may be used as a low‐cost electrode material in next generation of supercapacitors, while its low bandgap and high photoluminescence make it a promising material for optoelectronic applications.

Interface engineering and passivating contacts are key enablers to reach the highest efficiencies in photovoltaic devices. While printed carbon-graphite back electrodes for hole-transporting material (HTM)-free perovskite solar cells (PSCs) are appealing for fast commercialization of PSCs due to low processing costs and extraordinary stability, this device architecture so far suffers from severe performance losses at the back electrode interface. Herein, a 2D perovskite passivation layer as an electron blocking layer (EBL) at this interface to substantially reduce interfacial recombination losses is introduced. The formation of the 2D perovskite EBL is confirmed through X-ray diffraction, photoemission spectroscopy, and an advanced spectrally resolved photoluminescence microscopy mapping technique. Reduced losses that lead to an enhanced fill factor and V-OC are quantified by electrochemical impedance spectroscopy and J(SC)-V-OC measurements. This enables reaching one of the highest reported efficiencies of 18.5% for HTM-free PSCs using 2D perovskite as an EBL with a significantly improved device stability.

The electrically insulating space layer takes a fundamental role in monolithic carbon-graphite based perovskite solar cells (PSCs) and it has been established to prevent the charge recombination of electrons at the mp-TiO2/carbon-graphite (CG) interface. Thick 1 μm printed layers are commonly used for this purpose in the established triple-mesoscopic structures to avoid ohmic shunts and to achieve a high open circuit voltage. In this work, we have developed a reproducible large-area procedure to replace this thick space layer with an ultra-thin dense 40 nm sputtered Al2O3 which acts as a highly electrically insulating layer preventing ohmic shunts. Herewith, transport limitations related so far to the hole diffusion path length inside the thick mesoporous space layer have been omitted by concept. This will pave the way toward the development of next generation double-mesoscopic carbon-graphite-based PSCs with highest efficiencies. Scanning electron microscope, energy dispersive X-ray analysis, and atomic force microscopy measurements show the presence of a fully oxidized sputtered Al2O3 layer forming a pseudo-porous covering of the underlying mesoporous layer. The thickness has been finely tuned to achieve both electrical isolation and optimal infiltration of the perovskite solution allowing full percolation and crystallization. Photo voltage decay, light-dependent, and time-dependent photoluminescence measurements showed that the optimal 40 nm thick Al2O3 not only prevents ohmic shunts but also efficiently reduces the charge recombination at the mp-TiO2/CG interface and, at the same time, allows efficient hole diffusion through the perovskite crystals embedded in its pseudo-pores. Thus, a stable V OC of 1 V using CH3NH3PbI3 perovskite has been achieved under full sun AM 1.5 G with a stabilized device performance of 12.1%.

This paper presents a rendering framework for the visualization of massive point datasets in the web. It includes highly interactive point rendering, cluster visualization, basic interaction methods, and importance-based labeling, while being available for both mobile and desktop browsers. The rendering style is customizable, as shown in figure 1. Our evaluation indicates that the framework facilitates interactive visualization of tens of millions of raw data points even without dynamic filtering or aggregation.

We demonstrate the effect of sheet conductivity and infiltration using the example of two graphite types, showing that, in general, the graphite type is very important. Amorphous and pyrolytic graphite were applied to carbon electrodes in fully printable carbon-based multiporous-layered-electrode perovskite solar cells (MPLE-PSCs): &lt, glass/F-doped SnO2/compact-TiO2/porous-TiO2+perovskite/porous-ZrO2+perovskite/porous-carbon+perovskite&gt, The power conversion efficiency (PCE) using amorphous graphite-based carbon (AGC) electrode was only 5.97% due to the low short-circuit photocurrent density (Jsc) value, which was due to the low incident photon-to-current efficiency (IPCE) in the short wavelength region caused by the poor perovskite filling into the porous TiO2-ZrO2 layers. Conversely, using pyrolytic graphite-based carbon (PGC) electrode, Jsc, open-circuit photovoltage (Voc), fill factors (FF), and PCE values of 21.09 mA cm−2, 0.952 V, 0.670, and 13.45%, respectively, were achieved in the champion device. PGC had poorer wettability and a small specific surface area as compared with AGC, but it had better permeability of the perovskite precursor solution into the porous TiO2/ZrO2 layers, and therefore a denser filling and crystallization of the perovskite within the porous TiO2/ZrO2 layers than AGC. It is confirmed that the permeability of the precursor solution depends on the morphology and structure of the graphite employed in the carbon electrode.

The determination of certified efficiency values for perovskite solar cells from current–voltage sweeps is under growing discussion. Here, we report for the first time a certified steady-state solar efficiency for a hole transport layer (HTL)-free perovskite cell of 12.6% measured continuously at maximum power point in an accredited laboratory. By applying a molten-salt-based MAPbI3 precursor solution, dense filling and improved perovskite crystallization inside the nanoporous graphite-based monolithic contact scaffold of the cell are achieved. A stabilized photovoltage as high as 1 V is achieved, representing the highest VOC reported for HTL-free MAPbI3-based devices. Charge transport properties are determined by switching from open- to short-circuit conditions. Strong and stable quenching of the photoluminescence indicates effective transportation and extraction of the photoexcited primary charge carriers. The existence of an efficient HTL-free device suggests that these cells are more of an n-p junctio...

This work addresses the alignment of a light spot onto photovoltaic laser power converters for power-by-light applications. A model to compare the alignment tolerances of different cell designs by means of the maximum acceptable misalignment is introduced. Monolithic interconnected multi-segment cells, which are commonly used as high-voltage devices, suffer from poor current matching for misaligned light spots. We show that the maximum acceptable misalignment of circular pie-shaped high-voltage devices decreases quickly with increasing number of series connected segments. A lower limit for the precision of the alignment procedure is only 5.1% of the cell radius. This precision requirement is three times higher than for single-segment cells (15.7%).

Photovoltaics (PV) is on the way to become a global key energy technology. As PV is replacing fossil fuel based technology, it contributes to reduce the global CO2-emissions. However, it should be kept in mind that the fabrication of PV modules is connected with CO2 emission. To fulfil the Paris climate goals, the global PV industry needs to grow in such a way that it will have a significant share in global carbon emissions. Research-driven approaches to reduce the carbon footprint of PV have strong impact on this development. We identify the glass substrate and encapsulation as the ultimate lower boundary for carbon footprint for long-term stable grid connected PV technologies. By the in-situ concept for perovskite solar cells we introduce a holistic design approach guided by this lower limit for photovoltaic modules with a low carbon footprint of only 5% of current silicon PV. The feasibility of this idea is demonstrated by the fabrication of an efficient pre-encapsulated perovskite in-situ cell. The device shows record efficiencies of certified, stabilized 9.3 %. This is the highest reported efficiency of such solar cells with lowest carbon footprint.

Although virtual reality hardware is now widely available, the uptake of real walking is hindered by the fact that it requires often impractically large amounts of physical space. To address this, we present VirtualSpace, a novel system that allows overloading multiple users immersed in different VR experiences into the same physical space. VirtualSpace accomplishes this by containing each user in a subset of the physical space at all times, which we call tiles; app-invoked maneuvers then shuffle tiles and users across the entire physical space. This allows apps to move their users to where their narrative requires them to be while hiding from users that they are confined to a tile. We show how this enables VirtualSpace to pack four users into 16m2. In our study we found that VirtualSpace allowed participants to use more space and to feel less confined than in a control condition with static, pre-allocated space.

The United Nations Sustainable Development Goals (SDGs) and their interactions in developing countries in general, and in Egypt specifically, form the basis of our review. Issues of energy and water supply, linked to agriculture in rural areas, combine several of the SDGs. The current status and the challenges for solar photovoltaic (PV) electricity production and water supply technologies in rural areas are critically described and an outlook on future developments is provided. The framework of the water–energy–food nexus approach and its relation to the SDGs globally in the MENA region and in Egypt is presented and recommendations are given on institutional governance and research and development to overcome the silo mentality and enhance sector collaboration on all levels as prerequisite to achieving the SDGs. The latest technical developments in PV and water technologies and their opportunities for rural development are outlined. Combined technical solutions are highlighted with examples from Egypt. Specifically, installed systems in various rural locations are presented, and their advantages and shortcomings are discussed. The review provides a context for the studies presented in the Special Section on Solar Energy Solutions for Electricity and Water Supply in Rural Areas, Journal of Photonics for Energy , Volume 9, Issue 4.

In addition to maintaining the GenBank® nucleic acid sequence database, the National Center for Biotechnology Information (NCBI) provides analysis and retrieval resources for the data in GenBank and other biological data made available through the NCBI web site. NCBI resources include Entrez, the Entrez Programming Utilities, MyNCBI, PubMed, PubMed Central, Entrez Gene, the NCBI Taxonomy Browser, BLAST, BLAST Link (BLink), Electronic PCR, OrfFinder, Spidey, Splign, Reference Sequence, UniGene, HomoloGene, ProtEST, dbMHC, dbSNP, Cancer Chromosomes, Entrez Genomes and related tools, the Map Viewer, Model Maker, Evidence Viewer, Trace Archive, Sequence Read Archive, Retroviral Genotyping Tools, HIV-1/Human Protein Interaction Database, Gene Expression Omnibus, Entrez Probe, GENSAT, Online Mendelian Inheritance in Man, Online Mendelian Inheritance in Animals, the Molecular Modeling Database, the Conserved Domain Database, the Conserved Domain Architecture Retrieval Tool, Biosystems, Peptidome, Protein Clusters and the PubChem suite of small molecule databases. Augmenting many of the web applications are custom implementations of the BLAST program optimized to search specialized data sets. All these resources can be accessed through the NCBI home page at www.ncbi.nlm.nih.gov.

Single junction photovoltaic devices composed of direct bandgap III-V semiconductors such as GaAs can exploit the effects of photon recycling to achieve record-high open circuit voltages. Modeling such devices yields insight into the design and material criteria required to achieve high efficiencies. For a GaAs cell to reach 28 % efficiency without a substrate, the Shockley-Read-Hall (SRH) lifetimes of the electrons and holes must be longer than 3 s and 100 ns respectively in a 2 μm thin active region coupled to a very high reflective (>99%) rear-side mirror. The model is generalized to account for luminescence coupling in tandem devices, which yields direct insight into the top cell’s non-radiative lifetimes. A heavily current mismatched GaAs/GaAs tandem device is simulated and measured experimentally as a function of concentration between 3 and 100 suns. The luminescence coupling increases from 14 % to 33 % experimentally, whereas the model requires an increasing SRH lifetime for both electrons and holes to explain these experimental results. However, intermediate absorbing GaAs layers between the two sub-cells may also increasingly contribute to the luminescence coupling as a function of concentration.

An elegant solution for the power supply of sensor electronics is the application of power-by-light technology. With this technology several challenges related to conventional copper wiring are inherently overcome; benefits are galvanic isolation, the suppression of electromagnetic interference, and the possibility to combine power and bidirectional data transmission in a single fiber link. In order to power sensor electronics efficiently, a supply voltage in the range 3 to 12 V is typically required. This paper deals with the photovoltaic laser power converter used to convert the transmitted optical power back into electricity. The advanced cell concepts of multi-junction and multi-segment cells are discussed which both aim at an increased output voltage on the device level, thereby eliminating the need for additional DC/DC conversion. Modeling and experimental results of GaAs based cells are presented, namely of single-junction 2- to 12-segment cells as well as of a dualjunction single-segment structure. A discussion of the pros and cons of the different concepts is given, focusing on the consequences of misalignment and temperature changes.

The NIH Xenopus Initiative is establishing many of the genetic and genomic resources that have been recommended by the Xenopus research community. These resources include cDNA libraries, expressed sequence tags, full-length cDNA sequences, genomic libraries, pilot projects to mutagenize and phenotype X. tropicalis, and sequencing the X. tropicalis genome. This review describes the status of these projects and explains how to access their data and resources. Current information about these activities is available on the NIH Xenopus Web site (http://www.nih.gov/science/models/xenopus/).