bluuebunny/crossref_metadata_2025_split huggingface dataset:
Solution‐Processable Hole‐Transporting Polymers: Synthesis, Doping Study and Crosslinking Induced by UV‐Irradiation or Huisgen‐Click Cycloaddition
Authors: Caldera‐Cruz Enrique , Zhang Kenan , Tsuda Takuya , Tkachov Roman , Beryozkina Tetyana , Kiriy Nataliya , Voit Brigitte , Kiriy Anton 
Published: January 2022

AbstractA pair of hole‐conducting polymers comprising 3,6‐linked carbazole and meta‐linked anisole derivatives having solubilizing moieties to enable their solution processability, and complementarily reactive side‐groups (azide and alkyne) for cross‐linking, are synthesized and characterized. The polymers can be cross‐linked either by thermal annealing at relatively low temperatures in the 85–110 °C range, or by UV irradiation. A general applicability of the latter for a photolithographic patterning of the hole conducting polymer is proven. The polymers have an ionization potential (IP) of 5.8 eV, close to the IP of a small molecule hole‐conductor tris(4‐carbazoyl‐9‐ylphenyl)amine (TCTA). In combination with a strong dopant hexacyano‐trimethylene‐cyclopropane (CN6CP), but not with commercial 2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane (F4TCNQ), the polymers can be efficiently p‐doped to increase their conductivity by 5–6 orders of magnitude, as measured in devices with a lateral setup. Taken together, these characteristics suggest that the synthesized polymers are promising candidates for their use in solution‐processable organic light‐emitting diodes as hole‐injection layer and hole‐transporting layer materials, which will be verified in the upcoming work.
All About the Interface: Do Residual Contaminants at A High‐Quality h‐BN Monolayer Perylene Diimide Interface Cause Charge Trapping?
Authors: Renn Lukas , Walter Lisa S. , Watanabe Kenji , Taniguchi Takashi , Weitz R. Thomas 
Published: January 2022

AbstractIntrinsic charge transport in molecularly thin organic semiconducting crystals is critically sensitive to the quality of the interfaces required to perform the electrical measurements. Most prominent are the dielectric–semiconductor and semiconductor–metal interface. While impacts from the latter on charge transport can be extracted by four‐terminal measurements, the impact of the dielectric interface can only be minimized, typically by utilizing inert dielectrics. Here, it is shown that charge transport in organic field‐effect transistors based on the n‐type small molecule N, N′‐di((S)‐1‐methylpentyl)‐1,7(6)‐dicyano‐perylene‐3,4:9,10‐bis(dicarboximide) (PDI1MPCN2) can be improved up to one order of magnitude by using hexagonal boron nitride (h‐BN) as dielectric, compared to a standard SiO2 substrate. Using temperature‐dependent electrical measurements, the charge‐transport properties of devices are systematically analyzed, and high four‐terminal mobilities of up to 5.0 cm2 V−1 s−1 are obtained. The high mobility likely stems from decreased charge‐carrier trapping at the semiconductor‐dielectric interface due to the smooth surface of the inert h‐BN. Nevertheless, the temperature dependencies of the mobility, threshold voltage, and interface‐state trap density suggest that charge‐carrier trapping at the dielectric‐semiconductor interface still exists. By comparing the data to transport studies performed on thin air‐gapped organic films, it is concluded that an interfacial layer (likely water or solvent residues) between h‐BN and the monolayer PDI1MPCN2 causes charge trapping.
Real‐Time Visualization of Hydrogen Distribution in Metals Using Polyaniline: An Ultrasensitive Hydrogenochromic Sensor
Authors: Kakinuma Hiroshi , Ajito Saya , Hojo Tomohiko , Koyama Motomichi , Akiyama Eiji 
Published: January 2022

AbstractHydrogen is one of the key elements for the economy based on renewable and sustainable resources. Because a very low concentration of hydrogen in metallic structural materials often causes hydrogen embrittlement and decreases their mechanical property, there is a great interest in the development of an inexpensive and versatile sensor for hydrogen in metals with high sensitivity and high spatial resolution. Here, real‐time visualization of atomic state hydrogen in a metal has been successfully achieved using a hydrogenochromic sensor consisting of a conventionally fabricated polyaniline layer and an interfacial Ni layer plated on the metal surface. The color change of the polyaniline layer due to its hydrogenation reaction can visualize the distribution of atomic state hydrogen in metals. Because the Ni interfacial layer functions as a catalyst for the hydrogenation reaction, the high sensitivity of ≈2 µmol m–2 and high spatial resolution of hundreds of micrometers are realized. This study opens a gate to a general approach for visualizing atomic state hydrogen in metals using polymers. In addition to the easy fabrication process and simple analytical method, the high sensitivity and high spatial resolution make the hydrogenochromic sensor promising for studying hydrogen behavior in metals.
Optoelectronic Devices Based on Scaffold Stabilized Black‐Phase CsPbI3Nanocrystals
Authors: Romero‐Pérez Carlos , Rubino Andrea , Caliò Laura , Calvo Mauricio E. , Míguez Hernán 
Published: January 2022

AbstractThe optoelectronic properties of lead halide perovskites are intimately related to their crystalline phase. For the case of cesium lead iodide (CsPbI3) several polymorphs meet the Goldschmidt tolerance factor, which determines their stability, and form broad band absorber and luminescent phases. However, at room temperature none of them are stable, which prevents their use in optoelectronics. In this work, bare CsPbI3nanocrystals are synthesized in the sub‐10 nm range in the “black”, light emitting, crystalline phase, using a pore controlled SiO2matrix that limits crystal size and confers a certain degree of strain that favors their stability. Quantum confinement effects allow the tuning of the optical properties of the CsPbI3nanocrystals by means of the crystal size. Their suitability as optoelectronic materials is demonstrated by building scaffold supported CsPbI3quantum dot based photovoltaic and light emitting devices.
Optimizing the Back Contact of Kesterites and Perovskites: Band Edge Design and Defect Engineering in Molybdenum Chalcogenides
Authors: Xiang Huiwen , Zhang Jinping , Liang Hanzhen , Zhu Rui , Liu Chengyan , Jia Yu 
Published: January 2022

AbstractBack contacts, as an important part of solar cell devices, play a critical role in efficient separation of carriers and reduction of interfacial recombination. Here, by analyzing interfacial band alignment, thickness and defect properties of back contacts, a design principle for back contacts is proposed to properly accommodate the interrelated factors of short‐circuit current (Jsc), open‐circuit voltage (Voc), series resistance (Rs), and nonradiative recombination centers (NRCs) at the same time. A preferred back contact should have (i) a high valance band maximum (VBM) and (ii) a low Fermi level relative to absorber to drive hole extraction and block electron leakage, (iii) a thin design under the premise of p+‐type characteristic to effectively reduce Rs, which also ensures a wide depletion region on the absorber side to promote hole collection, and (iv) no additional deep‐level defects as interfacial NRCs. Taking molybdenum chalcogenide as example, p+‐type MoSe2/MoS2 realized by group VB element doping satisfies the design principles and is promising as an excellent back contact for kesterite/perovskite solar cells. This study gives theoretical guidance for designing an ideal back contact and shows how to improve the photovoltaic performance of solar cells by interfacial optimization.
Smart Wireless Near‐Infrared Light Emitting Contact Lens for the Treatment of Diabetic Retinopathy
Authors: Lee Geon‐Hui , Jeon Cheonhoo , Mok Jee Won , Shin Sangbaie , Kim Su‐Kyoung , Han Hye Hyeon , Kim Seong‐Jong , Hong Sang Hoon , Kim Hwanhee , Joo Choun‐Ki , Sim Jae‐Yoon , Hahn Sei Kwang 
Published: January 2022

AbstractDiabetic retinopathy is currently treated by highly invasive repeated therapeutic injections and surgical interventions without complete vision recovery. Here, a noninvasive smart wireless far red/near‐infrared (NIR) light emitting contact lens developed successfully for the repeated treatment of diabetic retinopathy with significantly improved compliance. A far red/NIR light emitting diode (LED) is connected with an application‐specific integrated circuit chip, wireless power, and communication systems on a PET film, which is embedded in a silicone elastomer contact lens by thermal crosslinking. After in vitro characterization, it is confirmed that the retinal vascular hyper‐permeability induced by diabetic retinopathy in rabbits is reduced to a statistically significant level by simply repeated wearing of smart far red/NIR LED contact lens for 8 weeks with 120 µW light irradiation for 15 min thrice a week. Histological analysis exhibits the safety and feasibility of LED contact lenses for treating diabetic retinopathy. This platform technology for smart LED contact lens would be harnessed for various biomedical photonic applications.
Effect of the Oxygen Composition Control of HfOx Films on Threshold and Memory Switching Characteristics for Hybrid Memory Applications
Authors: Lee Seungwoo , Kim Seong Hun , Oh Seungyeol , Lee Donghwa , Hwang Hyunsang 
Published: January 2022

AbstractConsidering a high‐density vertical X‐point memory array, the film thickness of an active device for the selector and memory needs to be scaled down. Here, the authors propose an AgTe/HfOx‐based hybrid memory device with a film thickness of less than 10 nm by adopting a bilayer (HfO1.8/HfO2) film using precise composition control. Non‐volatile switching characteristics can be obtained by considering the formation of stable nanoscale Ag filaments in the nanoporous region in non‐stoichiometric HfO1.8 deposited via sputtering. By contrast, volatile switching characteristics are achieved by an unstable atomic‐scale Ag path in stoichiometric HfO2 deposited via plasma‐enhanced atomic layer deposition. Based on density functional theory calculations, it is confirmed that the stoichiometry of the HfOx film is the key parameter that controls the switching characteristics. The bilayer (HfO1.8/HfO2) device exhibits excellent hybrid memory characteristics, such as distinct read margin (>1.5 V), high ON/OFF ratio (>106), and extremely low OFF current (≈pA), for vertical X‐point memory applications.
Elucidating the Effect of Borate Additive in High‐Voltage Electrolyte for Li‐Rich Layered Oxide Materials
Authors: Li Yixuan , Li Weikang , Shimizu Ryosuke , Cheng Diyi , Nguyen HongNam , Paulsen Jens , Kumakura Shinichi , Zhang Minghao , Meng Ying Shirley 
Published: January 2022

AbstractLithium‐rich layered oxides (LRLO) have attracted great interest for high‐energy Li‐ion batteries due to their high theoretical capacity. However, capacity decay and voltage fade during the cycling impede the practical application of LRLO. Herein, the use of lithium bis‐(oxalate)borate (LiBOB) as an electrolyte additive is reported to improve the cycling stability in high voltage LRLO/graphite full cells. The cell with LiBOB‐containing electrolyte delivers 248 mAh g−1 initial capacity and shows no capacity decay after 70 cycles as well as 95.5% retention after 150 cycles over 4.5 V cycling. A systematic mechanism study for the LiBOB‐enabled cycling performance improvement is conducted. Analytical electron microscopy under cryo‐condition confirms the formation of a uniform interphase and less phase transformation on the LRLO particle, accompanied by less voltage decay in the cathode. The formation of B‐F species is identified in the cycled electrolyte, elucidating the HF scavenger effect of LiBOB. Due to less HF corrosion on both electrode interphases, a reduced amount of transition metal dissolution and redeposition on the graphite is proved, thereby mitigating the capacity decay in LRLO/graphite full cells. These findings suggest that the borate additive is a promising strategy to optimize high voltage electrolyte for the industrialization of LRLO.
Flexible Film‐Discharge‐Switch Assisted Universal Power Management System for the Four Operation Modes of Triboelectric Nanogenerators
Authors: Yan Wenjie , Liu Yuan , Chen Pengfei , Cao Leo N.Y. , An Jie , Jiang Tao , Tang Wei , Chen Baodong , Wang Zhong Lin 
Published: January 2022

AbstractTriboelectric nanogenerators (TENGs) are used to harvest high entropy energy. To optimize the energy harvesting, storage and effective utilization, a critical part is the power management system (PMS), which requires an ideal electrical switch as the key component. However, the current switch technologies cannot adapt and enhance the charging for the four operation modes of TENG simultaneously. Herein, a flexible film‐discharge‐switch (FDS), delivering an averaged charge‐enhance factor over 100 under four operation modes of TENG, compared to directly charging a capacitor with conventional rectifier is reported. More specifically, the charge‐enhancement factors of the FDS are 134.3, 64.7, 97.0, and 136.5 for the modes of contact‐separation, lateral sliding, single‐electrode, and freestanding triboelectric layer, respectively. Furthermore, the high flexibility, stability, simplicity, durability, and self‐driven design of FDS endows the switch the possibility of versatile applications in the four modes of TENGs and flexible PMSs in wearable TENG applications. The successful demonstration in TENGs shows the great potential of the FDS in various fields such as micro‐nano energy storage, distributed power supply, and self‐powered systems.
Ethnic and sociodemographic correlates of developmental dysplasia of the hip in newborns from Yucatan, Mexico
Authors: Mendez‐Dominguez Nina , Alvarez‐Baeza Alberto , Estrella‐Castillo Damaris , Lugo Roberto , Villasuso‐Alcocer Víctor , Azcorra Hugo 
Published: January 2022

AbstractObjectivesTo provide an insight of the incidence of congenital developmental dysplasia of the hip in newborns from Yucatan born between 2015 and 2019 and analyze its association with maternal sociodemographic characteristics and neonatal, pregnancy and delivery related aspects.MethodsRetrospective, population‐based study from Birth Registries database in Yucatan, Mexico between 2015 and 2019. Presence of hip dysplasia was described and analyzed considering three aspects (I) Maternal information (II) Pregnancy and birth (III) Neonatal examination. We obtained incidence rates from each year and the complete studied period. Association between hip dysplasia and maternal, neonatal and pregnancy/delivery variables was analyzed using logistic regression, unadjusted odds ratio and an adjusted model.ResultsHip dysplasia occurred in 13 per 10 000 live births. Significant associations were found between hip dysplasia and maternal place of residence in a city <50 000 inhabitants, without a local clinic. Propensity to give birth to a neonate with hip dysplasia increased with maternal age and ethnicity, in female newborns and when total number of pregnancy consultations summed <5. Newborns with hip dysplasia were heavier and less susceptible to be delivered vaginally. Congenital developmental hip dysplasia was comparatively more frequent among offspring of Mayan women and suboptimal access to medical care during pregnancy. Female neonates were affected the most, those first‐borns. Neonates with hip dysplasia were heavier and more susceptible to be born by cesarean section.ConclusionMaternal, neonatal, and perinatal factors are associated with DDH in Yucatecan infants born during 2015–2019. Factors that describe living conditions seems to have a more important effect on the presence of this condition.
Transformation of a Chiral Glycolic Acid to an Isoaurone: Stereochemical Assignment of a Benzilic Acid Rearrangment Product
Authors: Burke Anthony J. , Teixeira Carla S. S. , Sousa Sergio F. 
Published: January 2022

AbstractThe benzilic acid rearrangement (BAR) has been exploited with great effect over the last decades, used as the key step in many cases to afford complex target structures with interesting properties. Although the reaction is inherentely stereoselective in cyclic systems, the results achieved using acylic diketone systems can be less satisfactory. This report describes a highly stereoselective BAR in an acyclic system that gives a glycolic acid product which is then transformed via an elimination reaction to an unusual isoaurone product, in fact this latter product was the key to unravelling the stereochemistry of the glycolic acid product. The elimination reaction mechanism was studied using computational approaches.
Unexpected Synthesis of Oxadiazole Analogues: Characterization and Energetic Properties
Authors: Kumar Yadav Abhishek , Kumar Parasar , Ghule Vikas D. , Dharavath Srinivas 
Published: January 2022

AbstractAn attractive synthetic route was devaluped for making N‐(4‐(1,2,4‐oxadiazol‐3‐yl)‐1,2,5‐oxadiazol‐3‐yl) formamide (4) and di(1,2,4‐oxadiazol‐3‐yl) methanone O‐(nitrodi(1,2,4‐oxadiazol‐3‐yl)methyl) oxime (6) from commercially available inexpensive malononitrile starting material with easy purification, short experimental time and high yields at room temperature. The chemical structures of 4 and 6 were identified by NMR, IR, EA and verified by single‐crystal X‐ray studies. A plausible mechanism is proposed for the conversion of 4 to 6. Furthermore, both compounds have been evaluated for energetic applications. Based on their insensitive nature and good detonation performance, they are potential energetic materials.
Development and characterisation research on SnO2‐Al2O3‐NiO/SO42− catalysed epoxidation of soybean oil under hydraulic cavitation
Authors: Zhang Meng , Cheng Qianwei , Chen Tong , Wei Xiaoli , Meng Luli 
Published: January 2022

AbstractA new hydraulic cavitation‐assisted epoxidation scheme was developed by using a cost‐effective, environment‐friendly, and recyclable solid‐acid catalyst. SnO2‐Al2O3‐NiO/SO42− solid‐acid catalysts were prepared using co‐precipitation and impregnation methods, which were characterised by several techniques and analysed using the Hammett acidity function. The prepared catalysts were found to have a large specific surface area (53.95 m2/g) and abundant acid sites (94 μmol/g). Exhibits higher stability and more effective catalytic activity compared with H2SO4. Under the optimal reaction conditions, the relative conversion to oxirane of 86.97% was obtained in only 1.5 h of reaction time. Moreover, the catalyst could be easily separated and showed satisfactory catalytic activity after five reuse cycles. The current work has clearly demonstrated that the application of hydraulic cavitation technology to the solid‐acid‐catalysed epoxidation reaction of soybean oil can shorten the reaction time, increase the relative conversion to oxirane, and be a viable method with promising applications.
Synthesis, characterization, molecular docking, biological activity, and DNA cleavage studies of Cu(II), Co(II), Ni(II), Mn(II), and Cd(II) Schiff base complexes
Authors: El‐Sonbati Adel Z. , Diab Mostafa A. , El‐Sayed Ahmed K. , Abou‐Dobara Mohamed I. , El‐Sayad Sameh A. 
Published: January 2022

AbstractMetal complexes of Schiff base ligand 4‐((Z)‐(4‐nitrophenylimino)methyl)benzene‐1,3‐diol (H2L) derived from condensation of 2,4‐dihydroxybenzaldehyde and p‐nitroaniline were synthesized and characterized by elemental analysis, IR, 1H NMR spectra, magnetic moment, molar conductance, and ultraviolet (UV)–Visible and thermal analysis. The complexes were proposed to have the formula [M (HL)(OAc)2] where M = Cu (II), Co(II), Ni(II), Mn(II), and Cd(II). The Fourier transform infrared (FT‐IR) spectra showed that ligand is coordinated to the metal ions in bidentate manner with donor sites of the azomethine‐N, phenolic‐OH. The synthesized Schiff base ligand and its metal complexes (1)–(5) were screened for their antibacterial activity. Antifungal activities were determined against Fusarium oxysporum, Aspergillus niger, and Candida albicans. Complex (5) showed a high potential cytotoxic activity against growth human lung cancer tumor cell lines. The DNA cleavage properties of the ligand and its complexes have been investigated by gel electrophoresis whose results showed that the Cu(II) complex has a significant oxidative cleavage among other complexes. Addition of H2O2 to the cleavage reaction enhanced the complete DNA degradation for Cu(II) and Co(II) complexes and DNA cleavage for Mn(II) complex. Molecular docking study between the ligand and the receptors (Escherichia coli [3t88], Staphylococcus aureus [3q8u], prostate cancer [2q7l Hormone], breast cancer [1jnx Gene regulation], lung cancer [1x2j], and colon cancer [2hq6]) was carried out, and it was found that the ligand is an efficient compound for all these receptors.
Acidic wood extractives accelerate the curing process of emulsion polymer isocyanate adhesives
Authors: Özparpucu Merve , Sánchez‐Ferrer Antoni , Schuh Mathias , Wilhelm Bianca , Sarkar Riddhiman , Reif Bernd , Windeisen‐Holzhauser Elisabeth , Richter Klaus 
Published: January 2022

AbstractEmulsion polymer isocyanate (EPI) adhesive is one of the most widely used structural adhesives in the woodworking industry. However, there has been a lack of knowledge on how the EPI‐adhesive interacts with the chemical constituents of wood, in particular, with the wood extractives that are known to influence the bonding quality. In this study, the interactions of the EPI‐adhesive with the water extracts and selected extractives from European wood species were systematically investigated using different analytical techniques. While the alterations in the curing properties of the pure EPI‐adhesive and EPI‐adhesive‐extract mixtures were revealed by in situ rheology and Fourier‐transform infrared spectroscopy, evolved gas analysis, and pyrolysis‐gas chromatography/mass spectrometry, the solid‐state 13C nuclear magnetic resonance were performed for analyzing the final chemical composition of the cured adhesive. Moreover, the influence of the extraction on the mechanical bonding performance was tested by tensile‐shear tests. The study revealed significant interactions between the EPI‐adhesive and tannin‐rich, acidic wood extracts. The acidic chestnut and oak extracts catalyzed the curing reactions and led to a huge increase in the adhesive viscosity. These interactions might affect the bonding quality, for example, adhesive penetration depth and formation of bonding strength, therefore, careful attention is required when bonding acidic wood surfaces.
Trends in particulate matter generation from truck and bus radial tires using a wear tester
Authors: Ha Jin Uk , Lee Hyun Hee , Ryu Gyeongchan , Lee Pyoung‐Chan , Ko Youn Ki , Jeoung Sun Kyoung 
Published: January 2022

AbstractThis study aimed to analyze the trend of particulate matter (PM) generation from tires by nonexhaust systems. These types of PM are lesser known than the airborne PM generated from automotive exhaust systems. Specimens with rubber formulations similar to commercial tires for trucks and buses were artificially abraded, and the generated PM was analyzed. Abrasion of a specimen made of butadiene rubber, which is a synthetic rubber, generated lesser PM than a natural rubber specimen. This reduction of PM generation was particularly significant for PM10. Furthermore, using carbon black (a filler in tires) having small sized particles, the generation of PM2.5 was reduced to a large extent. To study the influence of tire aging on the increased generation of PM, rubber specimens were analyzed after prolonged exposure to a high temperature.