Trapping Structures Research Articles

Annual energy yield of mono- and bifacial silicon heterojunction solar modules with high-index dielectric nanodisk arrays as anti-reflective and light trapping structures.

While various nanophotonic structures applicable to relatively thin crystalline silicon-based solar cells were proposed to ensure effective light in-coupling and light trapping in the absorber, it is of great importance to evaluate their performance on the solar module level under realistic irradiation conditions. Here, we analyze the annual energy yield of relatively thin (crystalline silicon (c-Si) wafer thickness between 5 μm and 80 μm) heterojunction (HJT) solar module architectures when optimized anti-reflective and light trapping titanium dioxide (TiO2) nanodisk square arrays are applied on the front and rear cell interfaces, respectively. Our numerical study shows that upon reducing c-Si wafer thickness down to 5 μm, the relative increase of the annual energy yield can go up to 23.3 %rel and 43.0 %rel for mono- and bifacial solar modules, respectively, when compared to the reference modules with flat optimized anti-reflective coatings of HJT solar cells.

Origin, migration pathways, and prediction of high carbon dioxide accumulations in the Lower Saxony Basin (northwestern Germany): Part II

Predrill risk assessment for the presence of nonhydrocarbon gases in oil and methane reservoirs is challenging and perhaps commonly an underestimated task. Although the same assessment principles apply for source and migration scenarios, the interplay of both play elements in basin history is different because of diverse origins and oftentimes unusual occurrences of nonhydrocarbon gases. The southern upper Permian Zechstein-2-Carbonate (Ca2) fairway in northwestern Germany represents such a setting, where CO2 contents >60 vol. % have been encountered in an otherwise methane-dominated area. The CO2 is well constrained to be the product from thermal decomposition of ultra–deeply buried Devonian carbonates (part I published in this issue). In this study (part II), CO2-rich tectonic veins sampled for part I have been directionally reoriented in drill cores, showing a dominant northeast-southwest strike. Only very few faults can be identified in seismic data, connecting the deep CO2 source through the approximately 3-km-thick Carboniferous section with the Ca2 reservoir. Fluid inclusion analyses of hydrothermal cements from the northeast-striking veins reveal up to 100 mol % CO2, formation temperatures up to 315°C, and near-lithostatic pressure conditions. The northeast strike of the faults is parallel to the main contraction direction during Late Cretaceous basin inversion and therefore marks the most likely timing for CO2 migration. The high CO2 content wells are located within the hanging wall of seismically defined northeast-striking faults, enabling lateral injection of CO2 into downthrown Ca2 fault blocks. This pattern enhances predictability of nonhydrocarbon gases for neighboring trap structures and in similar petroliferous basins.

The STRIPAK component SipC is involved in morphology and cell-fate determination in the nematode-trapping fungus Duddingtonia flagrans.

The striatin-interacting phosphatase and kinase (STRIPAK) complex is a highly conserved eukaryotic signaling hub involved in the regulation of many cellular processes. In filamentous fungi, STRIPAK controls multicellular development, hyphal fusion, septation, and pathogenicity. In this study, we analyzed the role of the STRIPAK complex in the nematode-trapping fungus Duddingtonia flagrans which forms three-dimensional, adhesive trapping networks to capture Caenorhabditis elegans. Trap networks consist of several hyphal loops which are morphologically and functionally different from vegetative hyphae. We show that lack of the STRIPAK component SipC (STRIP1/2/HAM-2/PRO22) results in incomplete loop formation and column-like trap structures with elongated compartments. The misshapen or incomplete traps lost their trap identity and continued growth as vegetative hyphae. The same effect was observed in the presence of the actin cytoskeleton drug cytochalasin A. These results could suggest a link between actin and STRIPAK complex functions.

Modeling of the complex hydrocarbon traps by the shot domain acoustic finite difference method and data-processing

Numerical modeling studies have a widespread application in exploration seismology in order to understand the seismic reflection responses of hydrocarbon traps formed in relation to tectonic structure, lithological changes and unconformities in complex geological environments and to develop effective data processing strategies. In this study, the seismic modeling of two important hydrocarbon trap models (Granite Wash and Normal Fault Trap) was performed by the Finite Difference Method (FDM), which provides the solution of the acoustic wave equation. Seismic data models were carried out in the pre-stack shot environment, and the obtained shot data were passed through appropriate data-processing stages to obtain stack and migration (zero offset) sections. By converting the obtained migration sections to depth, the spatial location and dimensions of hydrocarbon traps on the section were determined and it has been observed that they are compatible by comparing with the initial geological models. Thus, the seismic responses of hydrocarbon trap structures were learned, the importance of data processing was understood, and zero offset cross-sections were obtained by processing of the generated synthetic shot records. Accordingly, it was observed that it is appropriate to make more and frequent shots in the investigation of granite wash type traps which are thin and short-width , whereas it is useful to make relatively less frequent shots in order to reduce the scattering intensity caused by the discontinuities of the fault type structures. Consequently, it is thought that before the field study for the hydrocarbon exploration, the modeling of the pre-stack shot instead of the post-stack modeling (zero offset) will contribute to the development of the data processing stages and the testing of the seismic section interpretation. In the future, such synthetic models and data processing will be developed for different complex trap structures and real data.

Modern immunopharmacological methods of discovering new properties of benzydamine by its influence on innate and adaptive immune cells

Abstract Introduction.Considering the development of technologies and techniques, it is highly relevant today to continue studying the features of interaction of drugs developed and introduced into clinical practice in the 1960s and 1980s with the elements of the immune system located in the mucosa, since many of these drugs have local dosage forms. One such drug is benzidamine hydrochloride, registered as a nonsteroidal anti-inflammatory drug with extended pharmacodynamic properties.Objective. To evaluate the effect of benzidamine hydrochloride preparation on the cells of innate and acquired immunity located in the mucosa in an in vitro model.Materials and Methods. Cell fractions of neutrophils isolated from patients with infectious inflammation were used in the study. Sterile isolated neutrophils from the venous blood of patients were transferred into RPMI-1640 medium, where the investigated pharmacological drug was added, and incubation with cells was performed. Fluorescence microscopy was used to detect and count neutrophil extracellular traps. Cell fractions of lymphocytes isolated from patients with infectious inflammation were also used in the study. A commercial drug containing benzidamine hydrochloride, Tantum Verde (Angelini Pharma S.p.a., Italy), was used in the study.Results and discussion. Benzidamine causes significant inhibition of neutrophil extracellular trap formation. This suggests that at the beginning of application the drug enhances the antimicrobial response of the body, and then as the concentration decreases it demonstrates classic anti-inflammatory properties. The drug also enhances the neutrophil extracellular trap structure. The total number of B-lymphocytes tends to normalize under the effect of benzidamine. These data allow us to conclude about the ability of the drug to attenuate the severity of the inflammatory process, apparently by inhibiting the action of inflammatory cytokines.Conclusion.In the course of the in vitro study it was shown that benzidamine hydrochloride (Tantum Verde) has immunomodulatory properties against innate immunity cells – neutrophils, and its anti-inflammatory properties against adaptive immunity cells – lymphocytes – were confirmed.

Evaluation of Microfluidic Channels With Thin Si Windows and Trapping Structures

We present the fabrication and evaluation of a microchannel with thin Si windows and a trapping structure for injected liquid samples, including an evaluation using tubing methods of polydimethylsiloxane eyelets, and Kovar. Yeast cells and latex particles were observed using a fluorescence microscope under atmospheric conditions and a scanning electron microscope (SEM) under vacuum. As moving and flowing liquid samples cannot be observed for a long time, a trapping structure in the microchannel is required. In our experiment using pole structures under a thin Si window in microchannels to trap liquid samples, we successfully observed them using the SEM under an accelerating voltage of 15 kV and an emission current of 75 μA. This result indicates the possibility of using higher accelerating voltages of electrons for higher observation resolutions at a lower power density of 2.3 kW/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . Microfluidic channels with a thin window would be a useful technique for monitoring liquid samples under vacuum. [2020-0367]

Light absorption enhancement and radiation hardening for triple junction solar cell through bioinspired nanostructures

Multi-junction solar cells constitute the main source of power for space applications. However, exposure of solar cells to the space radiation environment significantly degrades their performance across the mission lifetime. Here, we seek to improve the radiation hardness of the triple junction solar cell, GaInP/Ga(In)As/Ge, by decreasing the thickness of the more sensitive middle junction. Thin junctions facilitate the collection of minority carriers and show slower degradation due to defects. However, thinning the junction decreases the absorption, and consequently, the expected photocurrent. To compensate for this loss, we examined two bioinspired surface patterns that exhibit anti-reflective and light-trapping properties: (a) the moth-eye structure which enables vision in poorly illuminated environments and (b) the patterns of the hard cell of a unicellular photosynthetic micro-alga, the diatoms. We parametrize and optimize the biomimetic structures, aiming to maximize the absorbed light by the solar cell while achieving significant reduction in the middle junction thickness. The density of the radiation-induced defects is independent of the junction thickness, as we demonstrate using Monte Carlo simulations, allowing the direct comparison of different combinations of middle junction thicknesses and light trapping structures. We incorporate the radiation effects into the solar cell model as a decrease in minority carrier lifetime and an increase in surface recombination velocity, and we quantify the gain in efficiency for different combinations of junction thickness and the light-trapping structure at equal radiation damage. Solar cells with thin junctions compensated by the light-trapping structures offer a promising approach to improve solar cell radiation hardness and robustness, with up to 2% higher end-of-life efficiency than the commonly used configuration at high radiation exposure.

Morphology evolution of the light trapping structure using atmospheric plasma textured c-Si wafer for silicon solar cells

Applying atmospheric plasma etching to the surface texturing process of silicon solar cells is a promising strategy for the current photovoltaic manufacturing industry due to its low equipment cost and good fabrication flexibility. This paper investigates the morphology evolution of the silicon surface etched by an Ar/CF4/O2 plasma and the associated optical properties. Results show that the generation of the light trapping structure on the polished silicon surface can be divided into two stages on the basis of the multi-scale morphological images and the quantitative evaluation of roughness parameters. The initial roughening stage mainly involves the formation of high-frequency nanoroughness that can act as an effective medium layer with a gradual refractive index. The resulting optical medium effect can reduce the surface reflectance within a broad range of wavelengths. At the next texturing stage, the low-frequency and high-amplitude microroughness dominates the morphology of the etched silicon surface. It features inverted parabolic structures with a high aspect ratio, which can cause multiple reflections of the incident light. The optical medium effect resulting from the nanoroughness is also inherited. Thus, the anti-reflectance property of the etched silicon surface is greatly improved. This work demonstrates that the light trapping properties of silicon surface etched by atmospheric plasma jet are a synergy of the optical medium effect and geometrical optics. Insights into the morphology evolution and optical properties of the textured surfaces are important for developing a new surface texturing process of silicon solar cells.

Topology Optimization of Passive Cell Traps.

This paper discusses a flexible design method of cell traps based on the topology optimization of fluidic flows. Being different from the traditional method, this method obtains the periodic layout of the cell traps according to the cell trapping requirements by proposing a topology optimization model. Additionally, it satisfies the cell trapping function by restricting the flow distribution while taking into account the overall energy dissipation of the flow field. The dependence on the experience of the designer is reduced when this method is used to design a cell trap with acceptable trapping performance. By comparing the influence of the changes of various parameters on the optimization results, the flexibility of the topology optimization method for cell trap structure optimization is verified. The capability of this design method is validated by several performed comparisons between the obtained layouts and optimized designs in the published literature.

Effects of miscible CO2 injection on production recovery

Carbon dioxide (CO2) injection is implemented into the reservoir to further improve the oil production efficiency, by mixing with oil at reservoir condition, and becomes miscible. The miscibility affects the oil to become swelled and less viscous and thus easily flow through the reservoir. Most of the (CO2) EOR projects has higher recovery factor in miscible condition. Therefore, this article aims to determine the effects of the miscible (CO2) injection on production recovery in the Cornea Field. The Cornea Field is located in Browse Basin, Western Australia. It is a simple trap structure which is elongated and formed by unfaulted drape anticline over an eroded high basement. The importance of this research is that (CO2) injection has not been implemented in the Cornea Field since it is a complex reservoir. However, research showed that there was a high potential production recovery in this field. Therefore, research needs to be conducted to determine the effectiveness of the (CO2) injection on production recovery in this field. The model was validated, by comparing MMP obtained from the simulation model and correlation methods. The MMP of this reservoir is above 38 Bar. Sensitivity analysis on reservoir pressure, reservoir temperature and (CO2) injection rate was investigated. Oil production increases with the increase in reservoir pressure and reservoir temperature. As the (CO2) injection rate increases, oil production also increased. From the result, hence, this study should contribute to the knowledge gap in Cornea Field.

Effect of orbital trapping by bar resonances in the local U–V velocity field

ABSTRACT The effects in the local U–V velocity field due to orbital trapping by bar resonances have been studied computing 15 resonant families in a non-axisymmetric Galactic potential, considering the bar’s angular velocity between 35 and 57.5 ${\rm \, km\, s^{-1}{kpc}^{-1}}$. Only cases in the low, 37.5, 40 ${\rm \, km\, s^{-1}{kpc}^{-1}}$, and high, 55, 57.5 ${\rm \, km\, s^{-1}{kpc}^{-1}}$, velocity ranges give trapping structures that have some similarity with observed features in the velocity distribution. The resulting structures in the local U–V plane form resonant bands appearing at various levels in velocity V. Cases with angular velocity 40 and 55 ${\rm \, km\, s^{-1}{kpc}^{-1}}$ show the greatest similarity with observed branches. Our best approximation to the local velocity field by orbital trapping is obtained with a bar angular velocity of 40 ${\rm \, km\, s^{-1}{kpc}^{-1}}$ and a bar angle of 40°. With this solution, three main observed features can be approximated: (i) the Hercules branch at V = $-50\, {\rm \, km\, s^{-1}}$ produced by the resonance 8/1 outside corotation, and the close features produced by resonances 5/1 and 6/1, (ii) the newly detected low-density arch at V ≃ 40 ${\rm \, km\, s^{-1}}$ produced approximately by the resonance 4/3, (iii) the inclined structure below the Hercules branch, also observed in the Gaia DR2 data, produced by tube orbits around Lagrange point L5 at corotation. Some predicted contributions due to orbital trapping in regions of the U–V plane corresponding to the Galactic halo are given, which could help to further restrict the value of the angular velocity of the Galactic bar. No support by orbital trapping is found for the Arcturus stream at V$\approx \, -100\, {\rm \, km\, s^{-1}}$.

Development of the Digital Economy，Transformation of the Economic Structure and Leaping of the Middle-income Trap

At present, China’s economy is in the key stage of the transformation of development mode and the transformation of new and old kinetic energy. Whether it can successfully cross the middle-income trap has become an important issue of general concern. Driven by artificial intelligence, blockchain, cloud computing, big data and other underlying digital technologies, the fourth industrial revolution with the booming digital economy as its main content has provided important opportunities for China’s economy to “overtake” and cross the middle-income trap.In sharp contrast to the booming digital economy, few literatures focus on the impact of digital economy development on crossing the middle-income trap under the background of economic structure transformation. In particular, the research on how to promote high-quality economic development through the supply side and demand side of the economic structure transformation brought by the development of digital economy has not been mentioned. This study shows that: （1）The key to cross the middle-income trap is the transformation of development mode, the optimization of industrial structure, and the transformation of growth momentum brought by the deep integration of digital economy and real economy.（2）From the perspective of the supply side, digital economy can improve the quality and efficiency of the supply side and promote the structural reform and economic growth of the supply side from the following three aspects: First, the supply system is high-quality, efficient and diversified; second, the innovation system is networked, open and collaborative; third, the mode of production is modularized, flexible and socialized.（3）From the demand side, digital economy can help the new momentum of the “troika” by changing the direction of market investment, promoting consumption upgrading and cultivating export advantages.（4）To successfully cross the middle-income trap, we should adapt to the basic law of the succession of development stages, and promote the fundamental transformation of the driving force of economic growth; strengthen the data elements as the supporting role of digital economy, and boost the high-quality development of digital economy; promote the integration of digital economy and real economy, and accelerate the process of digital industrialization and industrial digitization.The possible contributions of this paper are as follows: First, it analyzes the domestic and international situations and challenges faced by China in crossing the middle-income trap, and points out the practical significance of the development of digital economy for China in crossing the middle-income trap. Second, from the perspective of economic structure transformation, it analyzes the potential of quality change, efficiency change and dynamic change of China’s economic development, which points out the direction for the transformation of new and old kinetic energy, the improvement of total factor productivity, and the high-quality development of economy and society. Third, it analyzes the role of digital economy in improving the efficiency of the supply side and accurately matching the supply and demand, and demonstrates the positive impact of digital economy on the supply side from the three aspects of supply system, innovation system and production mode. Fourth, it analyzes the specific ways of digital economy development to revive the demand side “troika”, and summarizes the mechanism from the three aspects of market investment direction, consumption upgrading and new export advantages. Fifth, it puts forward a Chinese plan to cross the middle-income trap under the trend of economic digital transformation, which provides theoretical support for the government to formulate relevant policies and cross the middle-income trap.

Seismic Imaging of the Mw 7.1 Ridgecrest Earthquake Rupture Zone From Data Recorded by Dense Linear Arrays

AbstractWe analyze seismograms recorded by four arrays (B1–B4) with 100 m station spacing and apertures of 4–8 km that cross the surface rupture of the 2019 Mw 7.1 Ridgecrest earthquake. The arrays extend from B1 in the northwest to B4 in the southeast of the surface rupture. Delay times between P wave arrivals associated with ∼1,200 local earthquakes and four teleseismic events are used to estimate local velocity variations beneath the arrays. Both teleseismic and local P waves travel faster on the northeast than the southwest side of the fault beneath arrays B1 and B4, but the velocity contrast is less reliably resolved at arrays B2 and B3. We identify several 1–2 km wide low‐velocity zones with much slower inner cores that amplify S waveforms, inferred as damage zones, beneath each array. The damage zones at arrays B2 and B4 also generate fault‐zone head and trapped waves. An automated detector, based on peak ground velocities and durations of high‐amplitude waves, identifies candidate fault‐zone trapped waves (FZTWs) in a localized zone for ∼600 earthquakes at array B4. Synthetic waveform modeling of averaged FZTWs, generated by ∼30 events with high‐quality signals, indicates that the trapping structure at array B4 has a width of ∼300 m, depth of 3–5 km, S wave velocity reduction of ∼20% with respect to the surrounding rock, Q‐value of ∼30, and S wave velocity contrast of ∼4% across the fault (faster on the northeast side). The results show complex fault‐zone internal structures (velocity contrasts and low‐velocity zones) that vary along fault strike.

Constructing polyaniline nanowire arrays as efficient traps on graphene sheets to promote compound synergetic effect in the assembled coating for multifunctional protective cotton fabrics

Multifunctional protective coating with a novel trap structure containing Graphene oxide (GO) and Polyaniline (PANI) arrays is constructed on the surface of cotton fabrics through in–situ polymerization and spray assisted layer–by–layer assembly. The construction of nanoscale protective coatings with controllable thickness and different compounds on the surface of the cotton fabrics through spray assisted layer–by–layer assembly can better exert the molecular interaction between different layers and synergistic effect of different elements. More importantly, unique structure of PANI arrays are grown on the surface of the cotton fibers and GO sheets play very important role on the improvement of multifunctional performances for the cotton fabrics. PANI arrays can accept more APP molecules to promote the flame retardant behavior and construct nearly closed subspace to resist heat and oxygen, accompanying with the formation of inorganic barrier layer, excellent self–extinguishing ability can be achieved through nanoscale coating. Particularly, (GO–PANI1.0)3 coated cotton fabric with a weight gain of 12.7 wt% possesses the excellent self–extinguished ability and minimizes the total heat release value about 82.5% of pristine cotton. In addition, the PANI and GO reduced partially during in–situ polymerization of aniline can present good conductive pathway, as a result, the coated fabric also exhibits significant antistatic property, while can remarkably inhibit the growth of E. coli and S. aureus. Therefore this novel strategy with facile and scalable features can provide reference for developing various kinds of cheap composite nanocoating for multifunctional advanced textiles.

Optimal design and photoelectric performance study of micro-lens light trapping structure for CIGS thin film solar cell in BIPV

In this paper, an optimal design method of micro-lens light trapping structure for thin film solar cells applied to building integrated photovoltaic (BIPV) is proposed. Under three common scenes of BIPV, including lighting roof, sunshade and building facade, the optimal design and photoelectric performance study of Copper Indium Gallium Selenium (CIGS) thin film solar cells with micro-lens light trapping structure are studied. Among the three kinds of micro-lens light trapping structures, V-shaped, semi-cylindrical and concave, the light capture performance of V-shaped micro-lens light trapping structure is the best. The V-shaped micro-lens light trapping structure with a vertex angle of 70° and a groove depth of 100 μm has the best light capture performance in lighting roof and sunshade scene, which can increase the annual radiation flux of the absorption layer incident surface by 4.45% and 2.84% respectively. The V-shaped micro-lens light trapping structure with a vertex angle of 60° and a groove depth of 200 μm has the best light capture performance in building facade scene, which can increase the annual radiation flux of the absorption layer incident surface by 7.63%. When the light source is vertically incident, these two V-shaped micro-lens light trapping structures can increase the short-circuit current density by 15.57% and 7.11% respectively.

Light-trapping structures for planar solar cells inspired by transformation optics.

Optimal light absorption is decisive in obtaining high-efficiency solar cells. An established, if not to say the established, approach is to texture the interface of the light-absorbing layer with a suitable microstructure. However, structuring the light-absorbing layer is detrimental concerning its electrical properties due to an increased surface recombination rate (owing to enlarged surface area and surface defects) caused by the direct patterning process itself. This effect lowers the efficiency of the final solar cells. To circumvent this drawback, this work theoretically explores a transformation optics (TrO) inspired approach to map the nanopatterned texture onto a planar equivalent. This offers a pattern with the same optical functionality but with much improved electrical properties. Schwarz-Christoffel mappings are used for ensuring conformality of the maps. It leads to planar, inhomogeneous, dielectric-only materials for the light trapping structure to be placed on top of the planar light-absorbing layer. Such a design strategy paves a way towards a novel approach for implementing light-trapping structures into planar solar cells.

Avalanche photodetectors with photon trapping structures for biomedical imaging applications.

Enhancing photon detection efficiency and time resolution in photodetectors in the entire visible range is critical to improve the image quality of time-of-flight (TOF)-based imaging systems and fluorescence lifetime imaging (FLIM). In this work, we evaluate the gain, detection efficiency, and timing performance of avalanche photodiodes (APD) with photon trapping nanostructures for photons with 450 nm and 850 nm wavelengths. At 850 nm wavelength, our photon trapping avalanche photodiodes showed 30 times higher gain, an increase from 16% to >60% enhanced absorption efficiency, and a 50% reduction in the full width at half maximum (FWHM) pulse response time close to the breakdown voltage. At 450 nm wavelength, the external quantum efficiency increased from 54% to 82%, while the gain was enhanced more than 20-fold. Therefore, silicon APDs with photon trapping structures exhibited a dramatic increase in absorption compared to control devices. Results suggest very thin devices with fast timing properties and high absorption between the near-ultraviolet and the near infrared region can be manufactured for high-speed applications in biomedical imaging. This study paves the way towards obtaining single photon detectors with photon trapping structures with gains above 106 for the entire visible range.

Configuration of Allocated Mangrove Areas and Protection of Mangrove-Dominated Muddy Coasts: Knowledge Gaps and Recommendations

Mangrove-dominated muddy coasts have been allocated for developing livelihood models, particularly in developing countries. Uncontrolled allocation causes the mangrove forests to be vulnerable and even severely eroded. Restoration of vulnerable and eroded coastal areas has been merely conservation-driven, leaving livelihood-oriented mangrove forests unprotected. As a consequence, mangrove-dominated muddy coasts have not been well-protected. How livelihood-oriented mangrove forests are configured towards protecting coasts and protecting local livelihoods remains a challenge. This study employed a critical review for addressing this matter. The results reveal that there is limited practical knowledge of configuring livelihood-oriented models for protecting the coasts. The configuration process reported in this study is merely based on technical recommendations in South East Asia to date. The recommended configuration commences with the first stage of voluntarily designating a certain percentage of allocated forests on the seaward side to protect coasts, relocating livelihood models in the gaps among current stands of mangrove forests landward. Abandoned ponds are ecologically restored using sediment trapping structures for providing suitable substrate for promoting regrowth of local mangrove species as the second stage, followed by designation of an appropriate percentage as mangrove belts on the seaward side. The two-step configuration is highly likely to be replicable and applicable nationally and regionally due to full consideration of different political, sociocultural, and environmental characteristics in Vietnam and Indonesia.

Vacuum system for EBIS charge breeder of the RAON heavy ion accelerator

An Electron Beam Ion Source (EBIS) will be utilized for charge breeder in the RAON heavy ion accelerator facility. The vacuum system for the RAON EBIS charge breeder is crucial part for the achievable charge state, breeding efficiency, and purity of the charge-bred beam. A strict vacuum level of about 10−11 mbar is required in the ion trap. The pumping system of the RAON EBIS charge breeder consists of turbo pumps (TMPs), cryo-pumps, and non-evaporable getter (NEG) ZAO modules. The material for the ion trap structures and vacuum chamber was chosen and handled carefully to satisfy the vacuum requirements in the manufacturing step with vacuum firing at 1050 °C for 2 h. A vacuum test of the ion trap section has been performed with baking, and final vacuum level reached 2.3 × 10−11 mbar. In this paper, the vacuum system of the RAON EBIS and test procedures and results are presented and discussed.

Complexity and diversity of motion amplification and control strategies in motile carnivorous plant traps.

Similar to animals, plants have evolved mechanisms for elastic energy storage and release to power and control rapid motion, yet both groups have been largely studied in isolation. This is exacerbated by the lack of consistent terminology and conceptual frameworks describing elastically powered motion in both groups. Iconic examples of fast movements can be found in carnivorous plants, which have become important models to study biomechanics, developmental processes, evolution and ecology. Trapping structures and processes vary considerably between different carnivorous plant groups. Using snap traps, suction traps and springboard-pitfall traps as examples, we illustrate how traps mix and match various mechanisms to power, trigger and actuate motions that contribute to prey capture, retention and digestion. We highlight a fundamental trade-off between energetic investment and movement control and discuss it in a functional-ecological context.