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This study presents unmatchedly selective ultranarrowband frequency-selective surfaces (FSSs) for a pioneering external RF front-end (RFFE) filtering solution integrated with diverse beamforming antenna modules. The limitations of current base station filters for 28 GHz are demonstrated, and an inventive approach that extends the boundaries of the filtering block by positioning it outside the RFFE for spatial reinforcement is newly devised. An innovative analysis of narrow-bandpass complementary resonator pairs is introduced, unlocking unprecedented selectivity by addressing the challenging issue of recalcitrant mutual coupling arising from a dispersive field distribution. This spatial methodology extends the frontier by seamlessly integrating field analysis with a mixed coupling theory previously established in the circuit domain. Subsequently, a trailblazing technique is proposed for precise control of coupling balance, utilizing field-manipulating vias to centralize the primary current in the complementary resonator. This approach achieves an average rejection of 60 dB across the stopband, ensuring robust stability for incident angles up to 70°, surpassing previous counterparts. Furthermore, it demonstrates a significantly improved roll-off in the transition band and achieves a remarkable 2.7% bandwidth (BW), comparable to the 850 MHz for the n261 band of 5G NR.

The pavement texture wavelength and mean texture depth (MTD) of the pavement macrotexture significantly affect functional performance. However, owing to its higher correlation with the wavelength, the Exposed Aggregate Concrete Pavement (EACP) texture was evaluated based on the MTD and exposed aggregate number (EAN) in the same location. The MTD contributes significantly to road surface friction and tire-pavement noise and is vital for anti-sliding and noise reduction. Conventional methods for MTD measurement require considerable human effort when the sample size is large and sensitive to the operator. Furthermore, it is time-consuming to measure the MTD together with the EAN. Recently, image-based estimation has become a new trend, owing to its economy and convenience. Therefore, this study aimed to estimate the MTD of the EACP pavement surface texture at an image-based level as an alternative measurement approach simultaneously within the EAN location. Initially, the image acquisition was created based on aerial photography. Subsequently, photogrammetry was used to reconstruct a high-resolution point cloud of the pavement texture. Subsequently, the MTD was estimated analytically from image-based point clouds. Experiments were conducted at over 60 locations in three field tests of the EACP in South Korea. The MTD results showed good agreement and a higher correlation between the image-based and sand-patch test (SPT) methods. The image-based method showed results higher than the SPT with a value of 22%. Therefore, the developed method can be used to estimate the MTD using the established regression equation.

This study presents transmissive reconfigurable intelligent surface (TRIS) unit cells (UCs) with slimmed liquid crystals (LCs), where the effective cell gap is electromagnetically tailored to control the LC using empirically practical voltage values. Prior LC-based transmissive UCs utilize thickened cell gaps at millimeter-wave frequencies due to limited parametric degrees of freedom, aiming for enhanced performance, but this approach is unfavorable in terms of LC controllability. Therefore, a coupled resonator-loaded UC featuring a dumbbell-shaped complementary loop with intrinsically reduced coupling strength is proposed, despite the close proximity due to the slimmed cell gap. Moreover, a cleverly designed asymmetrical topology is proposed, where the resonators are positioned apart from each other in the perpendicular direction of the coupled dominant current. The designed UC achieves a simulated phase tuning range (PTR) of 123° by employing only a single-layered LC with a cell gap of 0.21 mm, which is improved more than two times than that of the previously studied counterpart. In addition, an operating range of 27.9–29 GHz with reasonable loss sustainable for entire range of LC dielectric constant is attained successfully, contrary to previous works where low loss is maintained only for a single tone (ST) frequency.

This letter presents a liquid crystal (LC) tuned resonant series patch array that interpretively emulates simplified unidirectional traveling-wave operation by eliminating the dependency on the undesirably tuned reflection coefficient. The general term for the resonantly excited current of a series-fed topology involving the reflection coefficient is derived. Additionally, a newly defined array factor is introduced, incorporating LC-tuned reconfigurability of constituent unit elements. Furthermore, a unique element spacing that has been rebuffed in broadside arrays due to out-of-phase radiation is selected for improved scanning performance despite a confined phase-tuning range and simplified noniterative analysis. Moreover, the impedance matching procedure that successfully maintains the input matched condition against variations in the LC dielectric constant is established by modifying the slotted coupling topology. It is demonstrated that a significantly enhanced gain of 12.1 dBi and aperture efficiency of 30.1% are achieved at 28.5 GHz compared to previously studied counterparts for which measured results are unavailable, and huge loss is inevitably accompanied by topological limitations.

There has been a lot of basic and clinical research on Alzheimer's disease (AD) over the last 100 years, but its mechanisms and treatments have not been fully clarified. Despite some controversies, the amyloid-beta hypothesis is one of the most widely accepted causes of AD. In this study, we disclose a new amyloid-beta plaque disaggregating agent and an AD brain-targeted delivery system using porous silicon nanoparticles (pSiNPs) as a therapeutic nano-platform to overcome AD. We hypothesized that the negatively charged sulfonic acid functional group could disaggregate plaques and construct a chemical library. As a result of the in vitro assay of amyloid plaques and library screening, we confirmed that 6-amino-2-naphthalenesulfonic acid (ANA) showed the highest efficacy for plaque disaggregation as a hit compound. To confirm the targeted delivery of ANA to the AD brain, a nano-platform was created using porous silicon nanoparticles (pSiNPs) with ANA loaded into the pore of pSiNPs and biotin-polyethylene glycol (PEG) surface functionalization. The resulting nano-formulation, named Biotin-CaCl2-ANA-pSiNPs (BCAP), delivered a large amount of ANA to the AD brain and ameliorated memory impairment of the AD mouse model through the disaggregation of amyloid plaques in the brain. This study presents a new bioactive small molecule for amyloid plaque disaggregation and its promising therapeutic nano-platform for AD brain-targeted delivery.

The measurement of the angular chirp by misalignment of the stretcher used for chirp pulse amplification (CPA) and optimization of the stretcher were studied. A misalignment in the optical system based on the CPA technique, which expands and compresses pulses using gratings, leads to angular chirps with different propagation directions depending on the wavelength. The angular chirp causes tilted pulse fronts in the near-field and reduces the intensity at the focus. The conventional method of correcting the grating misalignment by measuring the tilted pulse front mainly measures the laser beam after the compressor, and it is difficult to apply it to the measurement of the angular chirp generated by the stretcher. To overcome this, the wavelength of the laser was controlled by installing a slit inside the mode-lock oscillator, and the angular chirp was measured by direct measurement of the direction of the stretcher output according to each wavelength. This method measures the angular chirp in a simple manner without installing an additional light source or complex optical system and can be easily used for general ultrashort high-power lasers based on the CPA technique.

This communication presents an initial disparate deployment of 1-bit hybrid units using p-i-n diodes in transmit reconfigurable intelligent surface (TRIS) combined with a rotated feed source to address the gain limitation of the existing 1-bit TRIS. Two types of hybrid units, with a radiation phase difference of 90° by the delay line, are proposed in this study. The TRIS aperture is divided into two sections based on two different radiation centers by rotated feed, and the hybrid units in each Section are initially configured to implement optimized quasi 2-bit beam collimation in the 0° and 40° for enhanced quantization loss. It is found that the array envelope is higher even in radiation directions other than the optimized directions, despite the initial disparate deployment of each section. Beamforming for –theta direction in the H-plane is only considered for the proof of concept with the smallest size of TRIS aperture. A $16\times16$ ( $7.6\times 7.6\,\,\lambda_{0}$ at 28 GHz) 1-bit hybrid TRIS offers gain enhancement of 0–5.6 dB in −70 ° to −0 ° directions of the array envelope compared with the conventional 1-bit TRIS. The proposed 1-bit hybrid TRIS yields an improved aperture efficiency of 24.4%.

Electric vehicles have attracted the attention of users because they do not burn fossil fuels and emit zero greenhouse gas emissions. Fuel cells have shown their potential to power vehicles as well. The most common fuel cell types as power sources for automobiles are i) Proton exchange membrane fuel cell (PEMFC) and ii) Solid oxide fuel cell (SOFC). Normally, the PEMFC is considered main propulsion system. On the other side, the SOFC is generally not considered for propulsion system but considered for auxiliary power unit (APU). In this paper, feedback linearization controller for solid oxide fuel cells is proposed. And the performance of proposed controller is simulated under current disturbances operation condition through Matlab simulation.

We give some natural sufficient conditions for balls in a metric space to have small intersection. Roughly speaking, this happens when the metric space is (i) expanding and (ii) well-spread, and (iii) a certain random variable on the boundary of a ball has a small tail. As applications, we show that the volume of intersection of balls in Hamming, Johnson spaces and symmetric groups decay exponentially as their centers drift apart. To verify condition (iii), we prove some large deviation inequalities ‘on a slice’ for functions with Lipschitz conditions. We then use these estimates on intersection volumes to 1) obtain a sharp lower bound on list-decodability of random q-ary codes, confirming a conjecture of Li and Wootters, and 2) improve the classical bound of Levenshtein from 1971 on constant weight codes by a factor linear in dimension, resolving a problem raised by Jiang and Vardy. Our probabilistic point of view also offers a unified framework to obtain improvements on other Gilbert-Varshamov type bounds, giving conceptually simple and calculation-free proofs for $q$ -ary codes, permutation codes, and spherical codes. Another consequence is a counting result on the number of codes, showing ampleness of large codes.

Glioblastoma multiforme (GBM) is the most aggressive malignant tumor. It is difficult to regulate GBM using conventional chemotherapy-based methods due to its anatomical structure specificity, low drug targeting ability, and limited penetration depth capability to reach the tumor interior. Numerous approaches have been proposed to overcome such issues, including nanoparticle-based drug delivery system (DDS) with the development of GBM site targeting and penetration depth enhancing moieties (e.g., peptides, sugars, proteins, etc.). In this study, we prepared four different types of nanoparticles, which are based on porous silicon nanoparticles (pSiNPs) incorporating polyethylene glycol (PEG), iRGD peptide (well-known cancer targeting peptide), and SIWV tetra-peptide (a recently disclosed GBM-targeting peptide), and analyzed their deep-tumor penetration abilities in cell spheroids, in GBM patient-derived tumoroids, and in GBM xenograft mice. We found that SIWV tetra-peptide significantly enhanced the penetration depth of pSiNPs, and its therapeutic formulation (temozolomide-loaded/SIWV-functionalized pSiNPs) showed a higher anticancer efficacy compared with other formulations. These findings hold great promise for the development of nanotherapeutics and peptide-conjugated drugs for GBM.

Here, we report the results of experiments regarding the chemical repositioning of 4‐(2‐hydroxyethyl)‐1‐piperazine ethane sulfonic acid (HEPES), a representative buffering agent. In this work, we confirmed that HEPEScould disaggregate amyloid plaques, a hallmark of Alzheimer's disease, and we verified its sustained‐release system (release for up to 2 weeks) via hybridization with a biocompatible polymer (Eudragit S100). A chemical repositioning of 4‐[2‐hydroxyethyl]‐1‐piperazine ethane sulfonic acid (HEPES) as an amyloid‐beta (Aβ) plaque disaggregating agent and its sustained‐release system were reported.

Herein, we report a method of upgrading unconventional crude oils and extra heavy fractions using supercritical methanol (scMeOH) and compare it to supercritical water (scH2O)-based and pyrolytic upgrading. The yields and properties of upgraded oil are explored as functions of operating parameters (temperature, pressure, and concentration) and feedstocks for high-acid crude oils (Laguna and Bachaquero-13), a heavy crude oil (Rubiales), and a vacuum tower bottom (VTB). As a result, scMeOH upgrading of unconventional crude oils at 400 °C and 30 MPa effectively reduced their asphaltene content to ∼0 wt % and increased that of naphtha–diesel fractions to 30–40 wt %. Conversely, a considerable amount of asphaltenes (8.8–10.0 wt %) was present in oil upgraded using scH2O and pyrolysis. Additionally, scMeOH upgrading resulted in a more effective reduction of the total acid number (TAN) of high-acid crude oils (<0.5 mg of KOH/g of oil) compared to values achieved by scH2O and pyrolysis methods. Finally, scMeOH treatment significantly reduced the metal (Ni, V, and Fe) content of the upgraded oil. The effective asphaltene content and TAN reduction realized in scMeOH was attributed to its hydrogen donation and esterification ability, with plausible mechanisms of scMeOH, scH2O, and pyrolytic upgrading presented and discussed in detail.

RNF40 (OMIM: 607700) is a really interesting new gene (RING) finger E3 ubiquitin ligase containing multiple coiled-coil domains and a C-terminal RING finger motif, which engage in protein–DNA and protein–protein interactions. RNF40 encodes a polypeptide of 1001 amino acids with a predicted molecular mass of 113,678?Da. RNF40 and its paralog RNF20 form a stable heterodimer complex that can monoubiquitylate histone H2B at lysine 120 as well as other nonhistone proteins. Cancer is a major public health problem and the second leading cause of death. Through its protein ubiquitylation activity, RNF40 acts as a tumor suppressor or oncogene to play major epigenetic roles in cancer development, progression, and metastasis, highlighting the essential function of RNF40 and the importance of studying it. In this review, we summarize current knowledge about RNF40gene structure and the role of RNF40 in histone H2B monoubiquitylation, DNA damage repair, apoptosis, cancer development, and metastasis. We also underscore challenges in applying this information to cancer prognosis and prevention and highlight the urgent need for additional investigations of RNF40 as a potential target for cancer therapeutics.

Experiments and demonstrations (E&Ds) have always been a very special part of the EMC and Signal Integrity/Power Integrity (EMC+SIPI) symposia - and for a good reason. Within the broad range of technical presentations, workshops and tutorials, practical demonstrations deliver the unique opportunity to experience the variety of hands-on hardware and software applications, performed by EMC experts right there, right then. Witnessing the actual execution of an experiment from the first row provides a different type of learning quality expanding its fundamental understanding, teaching new tricks or solutions, or even for the sake of inspiration - after all, who doesn't enjoy seeing their favorite EMC concept being implemented in action?

A facile method was introduced and demonstrated to synthesize zinc oxide (ZnO) nanorods (NRs) as an electron transporting layer (ETL) for organic solar cells (OSCs). Hydrothermal synthesis of the NRs showed a constant growth rate of 5.5 nm min−1 from germination to sub-micrometer length. The properties were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), absorption spectrophotometry and so on. Based on these measurements, the germinant growth mechanism and its corresponding orientation characteristics were investigated. As an ETL of the OSCs, ZnO NRs enhance the charge extraction from the active layer due to their increased interfacial surface area, but there is an optimal length because of the shunt path formation and UV absorption of long ZnO NRs. As a result, the OSC with the ZnO NRs as ETL shows power conversion efficiency (PCE) up to 6.2%. The J - V characteristics and incident photon-to-current conversion efficiency (IPCE) measurement also reveal that the efficiency enhancement is an assembly of individual results from optical, physical and electrical characteristic of the ZnO NRs. [ABSTRACT FROM AUTHOR]

A hybrid composite of silver nanoparticles (AgNPs) and porous silicon microparticles (pSiMPs) was developed and applied for the computed tomography (CT) scanning of the lungs as an image-guided localization agent. We confirmed the grafting of AgNPs on oxidized pSiMPs template using various analytical equipment, including a scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDS). The hybrid composite showed a high CT contrast intensity (>1000 HU) that enabled us to produce and view images of the lungs. In addition, it showed the ability to maintain a strong CT signal at the injected area of the rabbit’s lungs, up to an hour, without spreading. The lack of toxicity and immune response indicated that the composite could be fully utilized as a new image-guided localization agent of CT scans for lung cancer surgery.

Advanced renal cell carcinoma is not uncommon, but necessitates a multidisciplinary approach for optimal treatment. Targeted therapy has increased the likelihood of urologists managing patients in all disease stages. Neoadjuvant therapy is currently experimental. Systemic therapy for metastatic disease demonstrates survival benefits. The role of cytoreductive nephrectomy and adjuvant therapy is dependent on patient selection. Management of advanced renal cell carcinoma involves continued optimization of available agents and biomarker development. This article reviews the role of the urologist in medical and surgical therapies, including prognostication, management of locally advanced and metastatic disease, and provides the most recent clinical trial data.

Achieving high signal-to-noise ratio in chemical and biological sensors enables accurate detection of target analytes. Unfortunately, below the limit of detection (LOD), it becomes difficult to detect the presence of small amounts of analytes and extract useful information via any of the conventional methods. In this work, we examine the possibility of extracting “hidden signals” using deep neural network to enhance gas sensing below the LOD region. As a test case system, we conduct experiments for H2sensing in six different metallic channels (Au, Cu, Mo, Ni, Pt, Pd) and demonstrate that deep neural network can enhance the sensing capabilities for H2concentration below the LOD. We demonstrate that this technique could be universally used for different types of sensors and target analytes. Our approach can extract new information from the hidden signals, which can be crucial for next-generation chemical sensing applications and analytical chemistry.

Silicon oxycarbides (SiOCs) are considered promising anode materials for sodium-ion batteries. However, the mechanisms of Na+-ion storage in SiOCs are not clear. In this study, the mechanism of Na+-ion storage in high-temperature-synthesized SiOCs (1200–1400 °C) is examined. Phase separation of the oxygen (O)-rich and carbon (C)-rich SiOxCydomains of SiOC during synthesis was accompanied by the evolution of micropores, graphitic layers, and a silicon carbide (SiC) phase. The high-temperature-synthesized SiOCs exhibited a large voltage plateau capacity below 0.1 V (45–63% of the total capacity). Ex situ measurements and density functional theory simulations revealed that within the sloping voltage region, Na+-ion uptake occurs mainly in the defects, micropores, C-rich SiOxCyphase, and some O-rich SiOxCyphases. In contrast, in the voltage plateau below 0.1 V, Na+-ion insertion into the O-rich SiOxCyphase and formation of Na-rich Si compounds are the main Na+-ion uptake mechanisms. The generated SiC phase confers excellent long-term cyclability to the high-temperature-synthesized SiOxCy.

The non-serendipitous discovery of materials with targeted properties is the ultimate goal of materials research, but to date, materials design lacks the incorporation of all available knowledge to plan the synthesis of the next material. This work presents a framework for learning a continuous representation of materials and building a model for new discovery using latent space representation. The ability of autoencoders to generate experimental materials is demonstrated with vanadium oxides via rediscovery of experimentally known structures when the model was trained without them. Approximately 20,000 hypothetical materials are generated, leading to several completely new metastable VxOymaterials that may be synthesizable. Comparison with genetic algorithms suggests computational efficiency of generative models that can explore chemical compositional space effectively by learning the distributions of known materials for crystal structure prediction. These results are an important step toward machine-learned inverse design of inorganic functional materials using generative models.

This study aims to assess the contamination of water and fish with nine metals (Fe, Al, Pb, Cu, Zn, Cd, Ni, As, and Cr) emitted by four coal-fired power plants in Chungcheongnam-do, Korea. Samples were collected at sites near each coal-fired power plant during the summer and fall. Control samples were also collected for comparison with the study samples. The concentrations of metals ranged from 0.01 to 4,654 μg/L in water. Non-carcinogenic and carcinogenic risks are associated with human exposure to Pb and As. Managing the presence of metals in the water environment is crucial for preserving the aquatic ecosystem.

Dynamic changes in chromatin structure are crucial for diverse biological processes. Given the complexity of the epigenetic landscape, understanding the specificity of chromatin modification has been a major interest in the epigenetics field. Recent progress in biochemical and structural analyses in the field of chromatin biology has revealed that recognition of allosteric effectors and the subsequent conformational change(s) are central to the regulation of catalytic activities and functions of chromatin-modifying enzymes. Here, we review several examples of distinctive nucleosome features, including DNA methylation, histone modifications, and variable-length linker DNA, that allosterically regulate the enzymatic activities of chromatin modifiers to confer functional specificity in a given chromatin context. We further highlight the biological significance of these allosteric mechanisms and discuss their potential as emerging targets for selective modulation of chromatin architecture.

Although astaxanthin has promising physiological functions, its practical applications are limited by poor stability. Herein, astaxanthin was encapsulated in β-cyclodextrin (βCD) using CO2as a supercritical antisolvent (SAS). The effects of process conditions, including temperature (313–333 K), pressure (12–18 MPa), solution concentration (3–5 wt%), solution flow rate (0.8–1.2 mL min−1), and astaxanthin-to-βCD mole ratio (1:50, 1:25, or 1:10), on the encapsulation efficiency, particle morphology, and residual solvent content were investigated. Astaxanthin–βCD complex spheres with an average diameter of 0.44 ± 0.08 µm were produced at 313 K and 15 MPa with a solution concentration and flow rate of 5 wt%, and 1.0 mL min−1, respectively. Under these optimal conditions, almost complete encapsulation (99.6% encapsulation efficiency) and residual organic solvent removal (0.22 ppm in the complex) were achieved. Density functional theory analysis of the configuration of the astaxanthin–βCD complex indicate that the hydroxyl hydrogen atoms on an ionone ring of astaxanthin interact with the oxygen atoms of βCD, but the ionone ring does not fit deeply within the βCD cavity. Notably, the astaxanthin–βCD complex exhibits higher thermal stability and antioxidant activity than free astaxanthin. The findings suggest that βCD encapsulation via the SAS process can produce astaxanthin microparticles with potential utility for food and pharmaceutical applications.

To realize a more rapid and accurate detection technique for diverse trace molecules, surface-enhanced Raman scattering (SERS) analysis has been extensively investigated in recent decades. However, a practical fabrication method to scalably and reproducibly produce SERS substrates with highly effective SERS-active sites and extensive optical tunability still remains an important research target. Here, we present an electrochemical pathway to generate a high-performance SERS substrate. This method provides not only ultrahigh-density hot spots as a form of nanogaps for strong and uniform SERS signal enhancement but also tunable plasmonic properties for capability of matching the plasmonic resonance wavelength with that of the Raman excitation laser. The unique Au nanopillar array decorated with ultrafine Au nanoparticles records a high SERS signal enhancement effect, which enables trace-molecule detection on the entire measured area with highly reproducible signal intensity. Also, via aptamer-functionalization on this substrate, an extremely sensitive and highly selective SERS-based Hg2+ions detection sensor is demonstrated. Trace-amount (10 ppb) Hg2+ions can be selectively identified in a mixture solution containing six different metallic ion species as well as in a beverage containing numerous other components.

In order to develop a stable and efficient laser wakefield accelerator by transition injection, the characteristics of the plasma density generated in a gas medium by shock was experimentally measured. The density difference between before and after the shock, and the density after the shock are important parameters for determining the charge and energy of the electron beam in the transition injection scheme. Based on experiments, we developed an adjustment method of these parameters and measured the characteristics of the electron beam by using the shock structure. The shock structure in the gas medium was generated by inserting a blade in a supersonic gas nozzle, and plasma was generated by using a 16-TW laser. Before the shock, the density increases and after that, the density is the same as the density without the shock. The ratio of the density difference was in the range of ~ 0.1–0.6, which could be adjusted according to the position of the blade. The density after the shock was adjustable by varying the distance between the laser and the nozzle, and it was in a suitable range of ~ 5 × 1018cm −3–1.2 × 1019cm −3for the electron acceleration. The measured electron beam indicates that the position of the shock needs to be in the range of ~ 0.3–0.5 mm before the laser focal position in the vacuum because of faster laser focus due to self-focusing.

Crystalline Si and III–V compound semiconductors with appropriate band edge positions for the reduction of water have been widely utilized in photoelectrochemical (PEC) cells for the hydrogen evolution reaction (HER). However, the high cost of manufacturing those PEC cell photoabsorbers makes it difficult to achieve cost-effective hydrogen production. To overcome this issue, a new approach to fabricate a photoabsorber with low cost yet high performance for the HER is highly necessary. Here, we present a controlled fracture method, the so-called spalling process, to fabricate a cost-effective thin semiconductor applicable to the PEC HER. Using this method, a wafer-scale thin Si, whose thickness can be controlled from a few micrometers to sub-50 μm, was fabricated from a thick Si mother substrate without material loss. Pt nanoparticle-decorated 16 μm thick spalled Si with an np+rear junction exhibited an HER onset potential of 332 mV (vs reversible hydrogen electrode (RHE)) and a photocurrent density of 20.1 mA cm–2at 0 V (vs RHE), which are the best performances among previously reported planar-type thin Si-based photocathodes. Finally, we demonstrated that 20 μm thick GaAs could also be successfully fabricated by the spalling process, while exhibiting a PEC HER performance comparable to 350 μm thick bulk GaAs.

Because of their low price, design flexibility, and sustainability, organic-based electrode materials are considered one of the most promising next-generation alternatives to inorganic materials in Li-ion batteries. However, a clear understanding of the changes in the molecular crystal structure during Li-ion insertion/extraction and its relationship to excess capacity (over theoretical capacity) is still lacking. Herein, the tetralithium 1,2,4,5-benzenetetracarboxylate (Li4C10H2O8, Li4BTC) salt was prepared using a simple ion-exchange reaction at room temperature and under solvothermal conditions (100 °C). The solvothermally synthesized salt (Li4BTC-S) exhibited a well-ordered nanosheet morphology, whereas the room-temperature salt (Li4BTC-R) was comprised of irregularly shaped particles. During the cycling of Li4BTC-S, molecular rearrangement occurred to reduce the stress caused by repeated Li-ion insertion/extraction, resulting in a change in the crystal structure from triclinic to monoclinic and an increased free volume. This contributed to an increase in the reversible capacity to 1016 mAh g–1during the initial 25 cycles at 0.1 A g–1, and finally the capacity stabilized at ca. 600 mAh g–1after 100 cycles, which is much higher than its theoretical capacity (234 mAh g–1). Compared with Li4BTC-R, Li4BTC-S delivered a higher reversible capacity of 190 mAh g–1at a high current density of 2 A g–1, with an excellent long-term cyclability of up to 1000 cycles, which was attributed to the straight free volume columns and the low-charge-transfer limitation.

Replication fork reversal is one of the major pathways for reactivating stalled DNA replication. Many enzymes with replication fork reversal activity have DNA-unwinding activity as well, but none of the fork reversal enzymes in the SWI/SNF family shows a separate DNA-unwinding activity, raising the question of how they initiate the remodeling process. Here, we found ATP binding to Rad5 induces the unwinding of the leading arm of the replication fork and proximally positions the leading and lagging arms. This facilitates the spontaneous remodeling of the replication fork into a four-way junction. Once the four-way junction is formed, Rad5 migrates the four-way junction at a speed of 7.1 ± 0.14 nt/s. The 3′ end anchoring of the leading arm by Rad5’s HIRAN domain is critical for both branch migration and the recovery of the three-way junction, but not for the structural transition to the four-way junction.

Polymeric binder is extremely important for Si-based anode in lithium-ion batteries due to large volume variation during charging/discharging process. Here, natural rubber-incorporated chitosan networks were designed as a binder material to obtain both adhesion and elasticity. Chitosan could strongly anchor Si particles through hydrogen bonding, while the natural rubber could stretch reversibly during the volume variation of Si particles, resulting in high cyclic performance. The prepared electrode exhibited the specific capacities of 1350 mAh/g after 1600 cycles at the current density of 8 A/g and 2310 mAh/g after 500 cycles at the current density of 1 A/g. Furthermore, the cycle test with limiting lithiation capacity was conducted to study the optimal binder properties at varying degree of the volume expansion of silicon, and it was found that the elastic property of binder material was strongly required when the large volume expansion of Si occurred.

In this study, we demonstrate that lignin, which constitutes 30–40 wt % of the terrestrial lignocellulosic biomass and is produced from second generation biofuel plants as a cheap byproduct, is an excellent precursor material for sodium-ion battery (NIB) anodes. Because it is rich in aromatic monomers that are highly cross-linked by ether and condensed bonds, the lignin material carbonized at 1300 °C (C-1300) in this study has small graphitic domains with well-developed graphene layers, a large interlayer spacing (0.403 nm), and a high micropore surface area (207.5 m2g–1). When tested as an anode in an NIB, C-1300 exhibited an initial Coulombic efficiency of 68% and a high reversible capacity of 297 mA h g–1at 50 mA g–1after 50 cycles. The high capacity of 199 mA h g–1at less than 0.1 V with a flat voltage profile and an extremely low charge–discharge voltage hysteresis (<0.03 V) make C-1300 a promising energy-dense electrode material. In addition, C-1300 exhibited an excellent high-rate performance of 116 mA h g–1at 2.5 A g–1and showed stable cycling retention (0.2% capacity decay per cycle after 500 cycles). By comparing the properties of the lignin-derived carbon with oak sawdust-derived and sugar-derived carbons and a low-temperature carbonized sample (900 °C), the reasons for the excellent performance of C-1300 were determined to result from facilitated Na+-ion transport to the graphitic layer and the microporous regions that penetrate through the less defective and enlarged interlayer spacings.

We present the analysis of photovoltaic properties in perovskite solar cells to explore the impact of excitonic features, disorder, recombination, and space charge effects using temperature and photo-intensity dependence. Photo-intensity dependence reveals an enhancement of classical Einstein relation due to the presence of traps and formation of space charge effects resulting in reduced conductivity. Exciton versus free charge density upon photo-excitation is analyzed from temperature dependence of photocurrent. Temperature dependence of VOC is excellently explained by considering a combined energetic disorder in a solar cell, and a moderately high value of variance ~125 meV is obtained.

A long gas jet was used as a gas target for laser wake field acceleration to increase the energy and quality of the electron beam. When the plasma density was 7 × 1018cm−3, quasi monoenergetic electron beams with a maximum energy of 152 MeV, a beam divergence 3 mrad, and a pointing stability 4 mrad were generated with a 5 mm long gas jet. The maximum energy was close to the theoretical limit predicted from the bubble model. This means that the length of the plasma was sufficiently long to accelerate the electron to the dephasing length after the electrons were self-injected by self-focusing. As the plasma density increased, the dephasing length decreased and the electron energy decreased. The continuous injection with higher density plasmas generated highly diverging beams. As the laser power increased, a number of electron beams with different propagation directions were generated. As shown by the measured shadowgram, the laser was divided into several filaments and each filament accelerated electron beam having different directions. The electron beam generated at this time decreased as the laser energy decreased due the division of the laser into different directions.

Ternary bulk heterojunction (BHJ) system, dual electron donors and an acceptor, was studied for developing wide spectral range organic photodetectors (OPDs). With two electron donor polymers with different bandgaps and an efficient electron acceptor of [6,6]-Phenyl-C71-butyric acid methyl ester (PC70BM), different blend ratios for ternary BHJ OPD were examined to achieve high photoresponsivity over a wide spectral range. OPDs based on ternary BHJ showed improved photovoltage response compared to binary BHJ. Current-voltage (J-V) characteristics as a function of external bias and light illumination were measured to reveal the underlying charge recombination mechanism which is found to be dominantly ruled by space charge limit (SCL) effect. Additional in-depth analyses including absorbance, cross-section scanning electron microscope (SEM), incident photon-to-electron conversion efficiency (IPCE) were performed.

Stable and robust open-circuit voltage (VOC) is essential to achieve a long lifetime for polymer solar cells (PSCs). Here, we investigate the VOCburn-in loss mechanism on the basis of the analysis of electroluminescence quantum efficiency (EQEEL) and impedance measurements in amorphous PSCs, with an inverted structure having different electron transport layers (ETLs) of ZnO nanoparticles (NPs) and the sol–gel processed ZnO layer. We found that both charge recombination and energetic disorder account for a substantial proportion of the VOCburn-in loss. Moreover, varying the ETL significantly affected the degree of VOCburn-in loss, although relative contribution of these two factors remained constant. To accurately extract charge recombination-induced VOCloss, we applied a novel yet effective method that relates the EQEELof PSCs to charge recombination-induced VOCloss. Additional analyses, including those focused on light intensity (Plight)-dependent VOCand density of states, will provide an inclusive perspective on the degradation mechanism of VOCand development of stable PSCs.

A liquid carbon dioxide (l-CO2) based coating approach is developed for ultrathin, uniform, and conformal carbon coating of hierarchically mesoporous LiFePO4(LFP) nano/microspheres for fabricating high-energy-density and high-power-density carbon coated LFP (C-LFP) with long-term cyclability. The unique properties of l-CO2result in an ultrathin carbon layer (1.9nm) distributed all over the primary nano-sized LFP particles (20–140nm in diameter), forming a core (LFP)-shell (carbon) structure. This unique structure provides facile penetration of liquid electrolytes and rapid electron and Li-ion transport. C-LFP exhibits high reversible capacity, high energy and power density (168mAhg−1at 0.1C, 109Whkg−1and 3.3kWkg−1at 30C, respectively) with excellent long-term cyclability (84% cycle retention at 10C after 1000 cycles). In addition, the ultrathin and uniform carbon layer of the mesoporous microspheres allows a high tap density (1.4gcm−3) resulting in a high volumetric energy density (458WhL−1at a 30C rate). Furthermore, C-LFP presents a high capacity and stable cycling performance under low-temperature and high-temperature environment. Well-developed carbon coating approach in this study is simple, scalable, and environmentally benign, making it very promising for commercial-scale production of electrode materials for large-scale Li-ion battery applications.

A recent study has shown that the use of a semiconducting surfactant in hybrid bulk heterojunction solar cells based on poly[2-methoxy-5-(3',7'-dimethyloctyloxyl)-1,4-phenylene vinylene] and zinc oxide significantly increases their performance. To further study the mechanism underlying the improved performance resulting from the addition of a semiconducting surfactant, we compared the temperature and light intensity dependence of the current voltage characteristics and impedance spectra of devices that used no surfactant, an insulating oleic acid (OA) surfactant, or a semiconducting 2-(2-ethylhexyl)-1,3-dioxo-2,3-dihydro-1H-benzo[de]isoquinoline-6,7-dicarboxylic acid (BQ) surfactant. The temperature and light intensity dependence data enabled us to extract the activation energy for different devices, and we measured the junction resistance through impedance spectroscopy. The device that used BQ had significantly lower activation energy (9-12 meV) than that without surfactant or oleic acid (17-21 meV), thus indicating improved charge transport and consequently an increased short-circuit current. Furthermore, the impedance characteristics showed that the injection resistance, when the BQ surfactant was used, was lower than that when no surfactant or oleic acid was used. These experiments provide further evidence that the use of semiconducting surfactants is essential to improve the performance of hybrid bulk heterojunction solar cells.

In this paper, the effects of the plasma density on laser-accelerated electron beams for radiation therapy with a sharp density transition are investigated. In the sharp density-transition scheme for electron injection, the crucial issue is finding the optimum density conditions under which electrons injected only during the first period of the laser wake wave are accelerated further. In this paper, we report particle-in-cell simulation results for the effects of both the scale length and the densitytransition ratio on the generation of a quasi-mono-energetic electron bunch. The effects of both the transverse parabolic channel and the plasma length on the electron-beam’s quality are investigated. Also, we show the experimental results for the feasibility of a sharp density-transition structure. The dosimetric properties of these very high-energy electron beams are calculated using Monte Carlo simulations.

Photodynamic therapy (PDT) has been used to reduce cancerous and precancerous cells via reactive oxygen species (ROS) generation from photosensitizers. Numerous photosensitizers are available today to treat a variety of diseases, but their therapeutic efficacy is hindered within the tumor microenvironment, and there are safety concerns associated with their non-specific activation. In this work, we disclosed a nano-therapeutic based on in situ activatable nitrobenzene–cysteine–copper(II) nano-complexes (NCCNs) that work within cancer cells. Among the NCCNs, CyP shows outstanding potential as a promising candidate for programmed photodynamic cancer therapy with its unique properties such as (i) bright near-infrared imaging, (ii) chemodynamic therapeutic effect, (iii) photodynamic therapeutic effect (types I and II), and (iv) anti-cancer effect by anti-angiogenesis in early cancer stage under light. Overall, this work opens up exciting possibilities for the development of innovative and effective treatments for cancer, paving the way for future advancements in the clinical medicine field.

Fast degradation is a major issue with organic photovoltaics (OPVs). Integrating plasmonics with OPVs has improved their efficiency; however, the stability effects are unknown. We demonstrate that plasmonic effects can improve the lifetime and efficiency. The aging effects on charge carrier generation and transport are investigated. Confocal time-resolved photoluminescence of Au nanoparticle (NP) doped polymer blend was performed to understand the plasmonic effects on excited-state dynamics. Hot exciton generation is observed directly at the Au-NP surface, which contributed to achieving a nearly perfect exciton dissociation yield. We found that slow aging of the plasmonic effect and the hot exciton contribution are the reasons for the improved lifetimes of plasmon-enhanced OPVs. This work opens up a new direction for improving the stability of OPVs and enhancing the application of plasmonics.

AbstractThe effluent limitations of industrial wastewaters are based on uniform regulatory criteria for effluent discharge facilities in Korea. However, an individual effluent limitation for each effluent discharge facility is being applied for regulation of industrial wastewater in US and EU. This study is conducted to propose effluent limitations for the semiconductor and electronic component (SEC) manufacturing industry on the basis of the best practicable control technology (BPT) currently available reflecting on the wastewater characteristics. BPTs were evaluated using conventional pollutants including biological oxygen demand (BOD), chemical oxygen demand (COD), suspended solids (SS), total nitrogen (TN), and total phosphorus (TP). We found BPT for semiconductor manufacturer in Korea was coagulation and sedimentation → biological treatment → activated carbon filter → and sand filter. Based on this BPT, effluent limitations for the SEC manufacturing industry in Korea were BOD5with 1.81 mg/L, CODMnwith 1.22 mg/L, SS with 0.55 mg/L, TN with 13.98 mg/L, and TP with 0.05 mg/L, respectively. All of these values were substantially lower than current effluent limitations. This result indicates that effluent limitations need to be separated for industrial sectors in Korea.

We report the influence of post-treatment via the external pressure on the device performance of quantum dot (QD) solar cells. The structural analysis together with optical and electrical characterization on QD solids reveal that the external pressure compacts QD active layers by removing the mesoscopic voids and enhances the charge carrier transport along QD solids, leading to significant increase in JSCof QD solar cells. Increasing the external pressure, by contrast, accompanies reduction in FF and VOC, yielding the trade-off relationship among JSCand FF and VOCin PCE of devices. Optimization at the external pressure in the present study at 1.4–1.6 MPa enables us to achieve over 10% increase in PCE of QD solar cells. The approach and results show that the control over the organization of QDs is the key for the charge transport properties in ensemble and also offer simple yet effective mean to enhance the electrical performance of transistors and solar cells using QDs.

A highly efficient n-Si/p-Cu2O core-shell (C-S) nanowire (NW) photodiode was fabricated using Cu2O grown by atomic layer deposition (ALD) on a well-ordered Si NW array. Ordered Si nanowires arrays were fabricated by nano-sphere lithography to pattern metal catalysts for the metal-assisted etching of silicon, resulting in a Si NW arrays with a good arrangement, smooth surface and small diameter distribution. The ALD-Cu2O thin films were grown using a new non-fluorinated Cu precursor, bis(1-dimethylamino-2-methyl-2-butoxy)copper (C14H32N2O2Cu), and water vapor (H2O) at 140°C. Transmission electron microscopy equipped with an energy dispersive spectrometer confirmed that p-Cu2O thin films had been coated over arrayed Si NWs with a diameter of 150 nm (aspect ratio of ∼7.6). The C-S NW photodiode exhibited more sensitive photodetection performance under ultraviolet illumination as well as an enhanced photocurrent density in the forward biasing region than the planar structure diode. The superior performance of C-S NWs photodiode was explained by the lower reflectance of light and the effective carrier separation and collection originating from the C-S NWs structure.

We investigate the use of chitosan (CS) as a new cross-linkable and water-soluble binder for the Si anode of Li-ion batteries. In contrast to the traditional binder utilizing a hydrogen bond and/or van der Waals force-linked anode electrodes, CS can easily form a 3D network to limit the movement of Si particles through the cross-linking between the amino groups of CS and the dialdehyde of glutaraldehyde (GA). Chemical, mechanical, and morphological analyses are conducted by Fourier transform infrared spectroscopy, tensile testing, and scanning electron microscopy. The cross-linked Si/CS-GA anode exhibits an initial discharge capacity of 2782 mAh g–1with a high initial Coulombic efficiency of 89% and maintained a capacity of 1969 mAh g–1at the current density of 500 mA g–1over 100 cycles.

High-efficiency organic photovoltaics (OPV) with a PTB7: PC70BM photoabsorption layer were fabricated by adopting Li- and Cd-doped ZnO electron extraction layers. For devices with both Li- and Cd-doped ZnO, the performances were significantly improved, including the short-circuit current, open-circuit voltage, fill factor (FF), and power conversion efficiency. Furthermore, film characterization with techniques including X-ray diffraction, high-resolution transmission electron microscopy, and resistivity analysis was performed. The results suggest that the improved electrical properties of Li- and Cd-doped ZnO electron extraction layers with a doping ratio of approximately 6 at% are highly effective in achieving a power conversion efficiency of up to 8%.