bluuebunny/crossref_metadata_2025_split huggingface dataset:
Susceptible Surface Sulfide Regulates Catalytic Activity of CdSe Quantum Dots for Hydrogen Photogeneration
Authors: Fan Xiang‐Bing , Yu Shan , Wang Xian , Li Zhi‐Jun , Zhan Fei , Li Jia‐Xin , Gao Yu‐ji , Xia An‐Dong , Tao Ye , Li Xu‐Bing , Zhang Li‐Ping , Tung Chen‐Ho , Wu Li‐Zhu 
Published: December 2018

AbstractSemiconducting quantum dots (QDs) have recently triggered a huge interest in constructing efficient hydrogen production systems. It is well established that a large fraction of surface atoms of QDs need ligands to stabilize and avoid them from aggregating. However, the influence of the surface property of QDs on photocatalysis is rather elusive. Here, the surface regulation of CdSe QDs is investigated by surface sulfide ions (S2−) for photocatalytic hydrogen evolution. Structural and spectroscopic study shows that with gradual addition of S2−, S2− first grows into the lattice and later works as ligands on the surface of CdSe QDs. In‐depth transient spectroscopy reveals that the initial lattice S2− accelerates electron transfer from QDs to cocatalyst, and the following ligand S2− mainly facilitates hole transfer from QDs to the sacrificial agent. As a result, a turnover frequency (TOF) of 7950 h−1 can be achieved by the S2− modified CdSe QDs, fourfold higher than that of original mercaptopropionic acid (MPA) capped CdSe QDs. Clearly, the simple surface S2− modification of QDs greatly increases the photocatalytic efficiency, which provides subtle methods to design new QD material for advanced photocatalysis.
Reversible Control of Physical Properties via an Oxygen‐Vacancy‐Driven Topotactic Transition in Epitaxial La0.7Sr0.3MnO3−δ Thin Films
Authors: Cao Lei , Petracic Oleg , Zakalek Paul , Weber Alexander , Rücker Ulrich , Schubert Jürgen , Koutsioubas Alexandros , Mattauch Stefan , Brückel Thomas 
Published: December 2018

AbstractThe vacancy distribution of oxygen and its dynamics directly affect the functional response of complex oxides and their potential applications. Dynamic control of the oxygen composition may provide the possibility to deterministically tune the physical properties and establish a comprehensive understanding of the structure–property relationship in such systems. Here, an oxygen‐vacancy‐induced topotactic transition from perovskite to brownmillerite and vice versa in epitaxial La0.7Sr0.3MnO3−δ thin films is identified by real‐time X‐ray diffraction. A novel intermediate phase with a noncentered crystal structure is observed for the first time during the topotactic phase conversion which indicates a distinctive transition route. Polarized neutron reflectometry confirms an oxygen‐deficient interfacial layer with drastically reduced nuclear scattering length density, further enabling a quantitative determination of the oxygen stoichiometry (La0.7Sr0.3MnO2.65) for the intermediate state. Associated physical properties of distinct topotactic phases (i.e., ferromagnetic metal and antiferromagnetic insulator) can be reversibly switched by an oxygen desorption/absorption cycling process. Importantly, a significant lowering of necessary conditions (temperatures below 100 °C and conversion time less than 30 min) for the oxygen reloading process is found. These results demonstrate the potential applications of defect engineering in the design of perovskite‐based functional materials.
Multifunctional “Hydrogel Skins” on Diverse Polymers with Arbitrary Shapes
Authors: Yu Yan , Yuk Hyunwoo , Parada German A. , Wu You , Liu Xinyue , Nabzdyk Christoph S. , Youcef‐Toumi Kamal , Zang Jianfeng , Zhao Xuanhe 
Published: December 2018

AbstractSlippery and hydrophilic surfaces find critical applications in areas as diverse as biomedical devices, microfluidics, antifouling, and underwater robots. Existing methods to achieve such surfaces rely mostly on grafting hydrophilic polymer brushes or coating hydrogel layers, but these methods suffer from several limitations. Grafted polymer brushes are prone to damage and do not provide sufficient mechanical compliance due to their nanometer‐scale thickness. Hydrogel coatings are applicable only for relatively simple geometries, precluding their use for the surfaces with complex geometries and features. Here, a new method is proposed to interpenetrate hydrophilic polymers into the surface of diverse polymers with arbitrary shapes to form naturally integrated “hydrogel skins.” The hydrogel skins exhibit tissue‐like softness (Young's modulus ≈ 30 kPa), have uniform and tunable thickness in the range of 5–25 µm, and can withstand prolonged shearing forces with no measurable damage. The hydrogel skins also provide superior low‐friction, antifouling, and ionically conductive surfaces to the polymer substrates without compromising their original mechanical properties and geometry. Applications of the hydrogel skins on inner and outer surfaces of various practical polymer devices including medical tubing, Foley catheters, cardiac pacemaker leads, and soft robots on massive scales are further demonstrated.
Hybrid Loss‐Compensated Plasmonic Device
Authors: Hosseini Alast Fatemeh , Nikkhah Mohsen , Li Xiao , Ng Jack , Ghasemi Amirhossein B. , Latifi Hamid , Cheah Kok Wai 
Published: December 2018

AbstractHere it is studied how the active medium affects the Rabi‐analog splitting when an active plasmonic microcavity mode is coupled to a surface plasmon polariton mode. The incorporation of Rubrene‐like molecules in the plasmonic microcavity results in stronger modal coupling. Anticrossing is observed with a large Rabi‐analog splitting energy of 280 meV in the strong coupling regime. The active medium contributes to the split enhancement through channeling more energy toward the coupling. The variation of photoluminescence emission and exciton‐cavity mode coupling from the hybrid plasmonic microcavity are also measured. This work shows that by introducing an active medium in the microcavity, mode coupling between microcavity and surface plasmon polariton can be enhanced and the hybrid plasmonic device exhibits parity–time symmetry characteristics.
Dehydrative Synthesis of Functionalized Skipped Dienes from Stabilized Phosphonium Ylides and Allylic Alcohols in Water
Authors: Ma Xiantao , Yu Jing , Han Cuijie , Zhou Qiuju , Ren Mengjuan , Li Lixin , Tang Lin 
Published: December 2018

AbstractA mild and extra activator‐free dehydrative alkylation of stabilized phosphonium ylides with allylic alcohols in water is developed in the presence of [Pd(allyl)Cl]2/dppf catalyst. A wide range of aryl, heteroaryl, alkyl and even allylic tertiary alcohols can readily react with stabilized phosphonium ylides with high regioselectivity for the efficient synthesis of functionalized skipped dienes in moderate to high yields. The role of water was investigated by means of a high‐resolution mass spectrum and diffusion‐ordered spectroscopy nuclear magnetic resonance, and the results revealed that water might play a crucial role in the formation of the π‐allylpalladium complex via hydrogen bond. However, the present method is not suitable for water‐sensitive phosphonium ylides.magnified image
Soft Modular Electronic Blocks (SMEBs): A Strategy for Tailored Wearable Health‐Monitoring Systems
Authors: Yoon Jaeyoung , Joo Yunsik , Oh Eunho , Lee Byeongmoon , Kim Daesik , Lee Seunghwan , Kim Taehoon , Byun Junghwan , Hong Yongtaek 
Published: December 2018

AbstractPrecise monitoring of human body signals can be achieved by soft, conformal contact and precise arrangement of wearable devices to the desired body positions. So far, no design and fabrication methodology in soft wearable devices is able to address the variations in the form factor of the human body such as the various sizes and shapes of individual body parts, which can significantly cause misalignments and the corresponding inaccurate monitoring. Here, a concept of soft modular electronic blocks (SMEBs) enabling the assembly of soft wearable systems onto human skin with functions and layouts tailored to the form factors of individuals' bodies is presented. Three types of SMEBs are developed as fundamental building blocks for functional modularization. The physical design of SMEBs is optimized for a mechanically stable island‐bridge configuration. The prepared SMEBs can be integrated onto a target body part through rapid, room‐temperature (RT) assembly (<5 s) using an oxygen plasma‐induced siloxane bonding method. A soft metacarpophalangeal (MP) joints flexion monitoring system that is tailored to allow for accurate monitoring for multiple individuals with unique joint and hand sizes is demonstrated.
Metal Hexaboride Work Functions: Surface Configurations and the Electrical Double Layer from First‐Principles
Authors: Schmidt Kevin M. , Misture Scott T. , Graeve Olivia A. , Vasquez Victor R. 
Published: December 2018

AbstractMetal hexaborides are ionic crystals having exceptional thermochemical stability and unique electrochemical behavior, including low work functions, making these materials ideal for electron emission applications. Here, the importance of specific interfacial properties for the development of efficient cathode devices is examined. In particular, the electrostatic behavior of BaB6, CaB6, LaB6, and SrB6 surfaces having various terminal configurations and surface coverage is studied using a repeated symmetric slab model with self‐consistent field calculations. The calculated work functions for each system are found minimal for a monolayer cation coverage and monotonically approach the experimental value for pure boron as cations are subsequently removed. Using three patterns to sample the surface space on stoichiometric slabs with identical surface composition, it is found that configurational changes can substantially alter the calculated work function. Further examination of the bonding charge densities suggest the low work functions typically observed in these materials are mainly due to the electrical double layer formed at the surface, rather than an inherent bulk property. This provides evidence suggesting that a variety of experimental observations may be due to surface features resulting from different preparatory methods. Significant electron density shifts are observed only few atomic layers deep leaving most of the bulk material unaltered.
Scaling of High‐Performance Organic Permeable Base Transistors
Authors: Al‐Shadeedi Akram , Liu Shiyi , Kaphle Vikash , Keum Chang‐Min , Lüssem Björn 
Published: December 2018

AbstractOrganic permeable‐base transistors (OPBTs) show potential for high‐speed, flexible electronics. Scaling laws of OPBTs are discussed and it is shown that OPBT performance can be increased by reducing their effective device area. Comparing the performance of optimized OPBTs with state‐of‐the‐art organic field‐effect transistors (OFETs), it is shown that OPBTs have a higher potential for an increased transit frequency. Not only do OPBTs reach higher transconductance values without the need for sophisticated structuring techniques, but they are also less sensitive to parasitic contact resistances. With the help of a 2D numerical model, the reduced contact resistances of OPBTs are explained by a homogeneous injection of current across the entire emitter electrode, compared to injection in a small area along the edge of the source of OFETs.
Adaptive behavior in adolescents and adults with Down syndrome: Results from a 6‐month longitudinal study
Authors: Spiridigliozzi Gail A. , Goeldner Celia , Edgin Jamie , Hart Sarah J. , Noeldeke Jana , Squassante Lisa , Visootsak Jeannie , Heller James H. , Khwaja Omar , Kishnani Priya S. , Liogier d'Ardhuy Xavier 
Published: December 2018

Measures of adaptive behavior are important in the assessment and treatment of individuals with intellectual disabilities (ID). The purpose of the current study was to evaluate the stability of an established and a novel measure of adaptive behavior over time, and their suitability as outcome measures in clinical trials targeting individuals with Down syndrome (DS). This 6‐month, longitudinal, noninterventional, multinational study included adolescents (12–17 years) and adults (18–30 years) with DS. Participants were from seven countries (11 different sites) with English, Spanish and French as their native language. The Vineland Adaptive Behavior Scales‐II (VABS‐II) and a newly developed Clinician Global Impression (CGI) scale were administered at baseline, 1 and 6 months. Adults had lower composite standard scores on all domains of the VABS‐II compared with adolescents. The communication domain was a weakness relative to the socialization and daily living skills domains on the VABS‐II and the CGI‐Severity scale. These findings were stable over 6 months, as exhibited by high intraclass correlations (>0.75). These results provide valuable baseline data for use in trial design and endpoint selection for studies including individuals with DS.ClinicalTrials.gov identifier: NCT01580384.
Characteristics and management of sinonasal paragangliomas: a systematic review
Authors: Nguyen Brandon K. , Patel Nirali M. , Arianpour Khashayar , Svider Peter F. , Folbe Adam J. , Hsueh Wayne D. , Eloy Jean Anderson 
Published: December 2018

BackgroundParagangliomas of the nasal cavity and paranasal sinuses, although exceedingly rare, can exhibit frequent and aggressive recurrences. Our objective was to evaluate tumor characteristics, clinical course, management, and associated complications of sinonasal paragangliomasMethodsA systematic review of the literature was performed utilizing the Preferred Reporting Items for Systematic Reviews and Meta‐Analysis (PRISMA) guidelines, searching for sinonasal paraganglioma. Studies meeting inclusion criteria were assessed for level of evidence. Patient demographics, tumor characteristics, primary intervention, and other clinical characteristics were evaluated.ResultsForty‐five relevant studies encompassing 54 patients with sinonasal paraganglioma were identified. The most common tumor locations were the nasal cavity (66.7%), ethmoid sinuses (22.2%), maxillary sinuses (7.4%), and sphenoid sinuses (3.7%). Common presenting symptoms included recurrent epistaxis (68.5%), nasal obstruction (53.7%), and headache (13.0%). Tumors were malignant in 28.6% of patients. Only 4 cases (7.4%) involved functional tumors. Initial management was always surgical, via either an open (63.0%) or endoscopic (33.3%) approach. Radiotherapy was used as adjunctive treatment in 10 cases (18.5%). Recurrence rate was 21.7% and occurred between 12 to 156 months after initial resection. The overall survival was 87.0% with a metastatic rate of 8.7%.ConclusionSinonasal paragangliomas are vascular neoplasms manifesting clinically with recurrent epistaxis and nasal obstruction. Management goals are total resection with clear margins and long‐term follow‐up due to tendency for local recurrence. Radiotherapy has been utilized as adjuvant therapy with variable results. Further randomized controlled studies may be invaluable in elucidating these findings.
Long‐term revision rates for endoscopic sinus surgery
Authors: Smith Kristine A. , Orlandi Richard R. , Oakley Gretchen , Meeks Huong , Curtin Karen , Alt Jeremiah A. 
Published: December 2018

BackgroundReported revision rates for endoscopic sinus surgery (ESS) for chronic rhinosinusitis (CRS) vary significantly. Several investigations examining revision rates for ESS have been limited by duration of follow‐up, academic centers, or small surgeon cohorts. The objective of this study was to define the long‐term revision rates for ESS and to determine those unique patient factors that increase the risk of revision ESS.MethodsThe Utah Population Database was queried for Current Procedural Terminology codes for ESS from 1996 to 2016. Patient demographics and comorbid diagnoses were collected. Revision rates and risk factors for surgery were determined by Cox proportional hazard modeling.ResultsA total of 29,934 patients were identified, with a mean length of follow‐up of 9.7 years. The long‐term revision rate was found to be 15.9%. The mean time between surgeries decreased with higher number of revision surgeries. The time between the first and second surgery was 4.39 years and the time between the fourth and fifth surgery decreased to 2.18 years. Female gender, older age at first surgery, nasal polyps, comorbid asthma, allergy, and a family history of CRS all increased the risk of requiring revision surgery (p < 0.001).ConclusionThe long‐term revision rate for ESS exceeds 15% and the time between revision surgeries decreased with each additional surgery being performed. Unique patient factors increased the risk of requiring revision ESS. Understanding patients’ risk for revision surgery may help physicians select and counsel patients with CRS undergoing ESS.
Kinetische Racematspaltung tertiärer Propargylalkohole durch enantioselektive Cu‐H‐katalysierte Si‐O‐Kupplung
Authors: Seliger Jan , Dong Xichang , Oestreich Martin 
Published: December 2018

AbstractEine breite Palette racemischer tertiärer Propargylalkohole wird durch katalysatorkontrollierte enantioselektive Silylierung kinetisch gespalten. Diese nichtenzymatische kinetische Racematspaltung wird durch Cu‐H katalysiert und nutzt den kommerziell erhältlichen Katalysatorvorläufer MesCu/(R,R)‐Ph‐BPE und ein einfaches Hydrosilan als zur Racematspaltung eingesetztes Reagens. Sowohl alkyl,aryl‐ als auch dialkylsubstituierte Propargylalkohole reagieren, und besonders hohe Selektivitätsfaktoren werden erzielt, wenn der Alkinterminus eine TIPS‐Gruppe trägt, was außerdem einfache Funktionalisierung in dieser Position ermöglicht (s bis zu 207).
Programmed Degradation of Hydrogels with a Double‐Locked Domain
Authors: Lai Jinping , Abune Lidya , Zhao Nan , Wang Yong 
Published: December 2018

AbstractThe ability to control the degradation of a material is critical to various applications. The purpose of this study was to demonstrate a concept of controlling degradation by using a double‐locked domain (DLD). DLDs are molecular structures with two functional units that work cooperatively under environmental stimulation. One unit is triggered to transform without cleavage in the presence of the first stimulus, but this transformation enables the activation of the other unit for cleavage in the presence of the second stimulus. A DLD is presented that is activated to transform through intramolecular reconfiguration when exposed to light. After this transformation, the light‐triggered DLD can undergo rapid cleavage under acid treatment. When this DLD is used as the crosslinkers of hydrogels, hydrogels undergo rapid degradation after sequential exposure to light irradiation and acid treatment. Reversing the order of light irradiation and acid treatment or only using individual stimulation does not lead to comparable degradation. Thus, this study has successfully demonstrated the great potential of using DLDs to achieve programmable degradation of materials.
Tryptamine Synthesis by Iron Porphyrin Catalyzed C−H Functionalization of Indoles with Diazoacetonitrile
Authors: Hock Katharina J. , Knorrscheidt Anja , Hommelsheim Renè , Ho Junming , Weissenborn Martin J. , Koenigs Rene M. 
Published: December 2018

AbstractThe functionalization of C−H bonds with non‐precious metal catalysts is an important research area for the development of efficient and sustainable processes. Herein, we describe the development of iron porphyrin catalyzed reactions of diazoacetonitrile with N‐heterocycles yielding important precursors of tryptamines, along with experimental mechanistic studies and proof‐of‐concept studies of an enzymatic process with YfeX enzyme. By using readily available FeTPPCl, we achieved the highly efficient C−H functionalization of indole and indazole heterocycles. These transformations feature mild reaction conditions, excellent yields with broad functional group tolerance, can be conducted on gram scale, and thus provide a unique streamlined access to tryptamines.
Zeolite reinforced carboxymethyl cellulose‐Na+‐g‐cl‐poly(AAm) hydrogel composites with pH responsive phosphate release behavior
Authors: Singh Anupama , Sarkar Dhruba Jyoti , Mittal Shailja , Dhaka Rashmi , Maiti Pushkar , Singh Aarushi , Raghav Taruna , Solanki Dilip , Ahmed Nayan , Singh Shashi Bala 
Published: December 2018

ABSTRACTPhosphate fixation in soils is a matter of concern in agriculture. Conventional application of phosphorus fertilizer suffers from low P use constraint, particularly in acidic soils. Rhizosphere centric slow release strategy bears tremendous prospects. In the present study, monocalcium phosphate (MCP) was impregnated in zeolite reinforced CMC‐Na+‐g‐cl‐Poly(Aam) hydrogel composites with aim to develop slow phosphate release device for soil application. X‐ray diffraction, scanning electron microscopy, and Fourier transform‐infrared spectroscopy confirmed the successful synthesis of slow release fertilizer formulations. Presence of zeolite in composite matrix during polymerization resulted in higher MCP loading. The “burst release” phenomena under neutral aqueous environment as compared to diffusion led slow release mechanism under acidic condition suggesting that phosphate release from developed composite matrix was pH responsive. The developed materials possess potential to serve as tool for improving phosphate use efficiency under resource stress agriculture. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 47332.
Investigation of ureido‐attached vinyl MQ silicone resin on tracking and erosion resistance of addition‐cure liquid silicone rubber
Authors: Li Hongqiang , Li Yanping , Lai Xuejun , Cao Hongwei , Yuan Renxu , Zeng Xingrong 
Published: December 2018

ABSTRACTWith the growing incidence of extreme climate and serious pollution, the capability to resist high‐voltage arc discharge has been considered as one of crucial performances for silicone rubber in the field of electrical power. Herein, to enhance the tracking and erosion resistance of addition‐cure liquid silicone rubber (ALSR), a kind of ureido‐attached vinyl MQ silicone resin [hydrolytic condensation products of monofunctional silane (M) and tetrafunctional silane (Q)] (U‐VMQ) was synthesized. The chemical structure of U‐VMQ was characterized by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance, and the effects of U‐VMQ on the mechanical properties, thermal stability, and tracking and erosion resistance of ALSR were investigated. The results showed that U‐VMQ was beneficial for the improvement of mechanical properties and thermal stability of ALSR. With 2 phr of U‐VMQ containing 2.5 wt % of vinyl content, the ALSR successfully passed the inclined plane tracking at 4.5 kV, and the electrical erosion rate was only 0.13%. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47360.
New range domain carrier‐smoothed code filtering with dual‐frequency BDS data
Authors: Chen Chao , Chang Guobin , Zhang Shubi , Chen Guoliang , Luo Fei 
Published: December 2018

AbstractIn global navigation satellite system (GNSS) applications, the carrier‐smoothed code is a widely used technique to combine code pseudo‐range and carrier phase measurements. Unlike conventional methods, a method using dual‐frequency GNSS data to improve smoothing accuracy by eliminating ionosphere delay is described in this paper. In the recursive least‐squares theory for colored measurement errors framework, a global one‐step carrier‐smoothed code filter in range domain is proposed to overcome the limitations of traditional approaches. The correlations of the time‐differenced carrier phase measurements are considered. This approach avoids overly optimistically evaluating the estimate and improves the transient accuracy of the estimate. Compared with stepwise strategy, the one‐step method is superior and globally optimal. Experiments are conducted using real BDS data, and the performance of the proposed method is demonstrated.