bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mesoscopic and Microscopic Strategies for Engineering Plasmon‐Enhanced Raman Scattering
Authors: Li Zhi‐Yuan 
Published: June 2018

AbstractSurface plasmon resonance (SPR) in noble metal nanoparticles and nanostructures offers an efficient means to transport and localize the energy of light into some nanoscale space regions called hot spots, where the electromagnetic field is enhanced by many orders of magnitude upon the incident light. This local field enhancement can induce very huge enhancement of Raman signal for a molecule embedded within the hot spot, which has tremendous applications in surface‐enhanced Raman spectroscopy (SERS) and tip‐enhanced Raman spectroscopy (TERS). Here, a discussion is presented on how to engineer this SPR‐enhanced Raman scattering from both the mesoscopic and microscopic levels. The mesoscopic level focuses on engineering and optimizing the geometric and physical configurations of plasmonic nanoparticles in order to have as large as possible electromagnetic field enhancement factor in the hot spot. The microscopic level focuses on investigating the light–molecule interaction (both chemical and physical) in the microscopic level, either classical or quantum, in order to have deep and complete understanding of the key microscopic issues influencing the Raman scattering and then exploring microscopic means to further enhance the Raman scattering as large as possible. Although in many situations these two scopes can be considered separately, there are also many situations where these two scopes need to be considered together. A prominent example, discussed here, is the critical role of molecule Rayleigh scattering in a plasmonic nanogap. Furthermore, several important issues are pointed out that need attention and caution in exploring and evaluating the quantitative SPR‐based Raman enhancement, including the quantum plasmonics correction, surface and interface electron scattering correction, and the validity of classical electromagnetics and electrodynamics approaches used in single and few atom scale plasmonics.
All‐Solution‐Processed Metal Oxide/Chalcogenide Hybrid Full‐Color Phototransistors with Multistacked Functional Layers and Composition‐Gradient Heterointerface
Authors: Cho Sung Woon , Kim Young Been , Jung Sung Hyun , Baek Seung Ki , Kim Joo Sung , Lee Minkyung , Cho Hyung Koun , Kim Yong‐Hoon 
Published: June 2018

AbstractFor the development of cost‐effective, ultrasensitive, fast dynamic, and full‐color photodetection platforms, an all‐solution‐processed metal oxide/chalcogenide semiconductor hybrid‐structure‐based visible‐light phototransistor with (i) multistacked functional materials, (ii) a chemically stable solution‐based construction, and (iii) defect‐suppressed composition‐gradient heterointerfaces is proposed. Herein, the functional multistacked structure (a‐ZTO/cc‐CdS/a‐ZTO) consists of high‐mobility amorphous zinc tin oxide (ZTO) (a‐ZTO bottom), a high‐efficiency coarsened crystalline CdS (cc‐CdS) visible‐light absorber, and defective surface passivation a‐ZTO (top) to boost photosensitivity via efficient generation/transport and spontaneous separation/confinement of photocarriers. Chemically stable solution‐based multistacking is achieved via careful choice of chemically durable oxide and chalcogenide semiconductors (Sn‐eqi ZTO and CdS). The composition‐gradient heterointerfaces formed near ZTO/CdS and CdS/ZTO junctions via thermally activated healing processes provide instantaneous photoresponse and full‐color sensing performance. Finally, the all‐solution‐processed a‐ZTO/cc‐CdS/a‐ZTO hybrid phototransistor achieves repeatable/reproducible real‐time full‐color detection with high photosensitivity, fast phototransient speeds, and no persistent photocurrent behavior under dynamic stimulus using primary colors. It is believed that the all‐solution processed oxide/chalcogenide hybrid phototransistor with multistacked functional materials and composition‐gradient heterointerfaces will facilitate the development of cost‐efficient, ultrasensitive, fast dynamic, and full‐color visible‐light detection system.
Soft Lithography to Fabricate 3D Patterning Organic Microrings towards High‐Performance Near‐Infrared Laser Arrays
Authors: Zhang Zhaoyi , Wang Zhen , Xu Zhenzhen , Gao Qinggang , Liu Peng , Ren Jiahuan , Li Meili , Zhou Cong , Liao Qing , Fu Hongbing 
Published: June 2018

AbstractOptical resonator arrays are highly important fundamental units for integrated photoelectric devices, such as on‐chip logical circuits, high‐precision sensors, and laser displays. Whispering gallery mode (WGM) microrings (MRs) could reduce the optical losses and provide a small mode volume, which is helpful for the integration of miniaturized devices. However, there still is a great challenge to produce and pattern the circular resonator. Here, a facile poly(dimethylsiloxane) (PDMS) ring‐hole‐stamp confined solution‐growth method is used to fabricate organic (E)‐3‐(4‐(di‐p‐tolylamino)phenyl)‐1‐(1‐hydroxynaphthalen‐2‐yl)prop‐2‐en‐1‐one (DPHP) MR arrays. Low‐threshold multi‐mode near‐infrared lasing is successfully achieved in the single MRs and DPHP MR arrays at room temperature. At the same time, their lasing behaviors change obviously in the lasing intensity, emission position, lasing mode, and lasing threshold after contacting with water and NaOH solution. The present work is a major step for realizing compact near‐infrared optoelectronic devices.
Efficient and Color Stable White Quantum‐Dot Light‐Emitting Diodes with External Quantum Efficiency Over 23%
Authors: Zhang Heng , Su Qiang , Sun Yizhe , Chen Shuming 
Published: June 2018

AbstractWhite quantum dot light‐emitting diodes (WQLEDs) with different structures are developed. By mixing red (R), blue (B) and green (G) quantum dots (QDs) together, the optimal WQLEDs exhibit a peak current efficiency (CE) of 22.54 cd/A and an external quantum efficiency (EQE) of 7.07%. The relatively poor performance is due to the efficient nonradiative Förster resonant energy transfer (FRET) among B‐, G‐ and R‐QDs. To address this issue, tandem WQLEDs are developed. By stacking the blue and the yellow QLEDs, the two‐unit tandem WQLEDs exhibit a peak CE of 30.3 cd/A and a maximum EQE of 15.2%. To further improve the color stability and the efficiency, the R/G/B three‐unit tandem WQLEDs are developed, which exhibit an impressive CE of 55.06 cd/A, a high EQE of 23.88% and a high luminance of 65690 cd/m2, which are the highest values ever reported. Moreover, the optimal tandem WQLED exhibits a high color stability, a pure white color with a 1931 Commission International de I'Eclairage (CIE) coordinate of (0.33, 0.34) and a color rendering index of 80. The demonstrated tandem WQLEDs, with high efficiency, pure white color, high color stability and high color‐rendering, would be promising candidates for next generation solid‐state lighting and full‐color display.
High‐Efficiency Sky Blue to Ultradeep Blue Thermally Activated Delayed Fluorescent Diodes Based on Ortho‐Carbazole‐Appended Triarylboron Emitters: Above 32% External Quantum Efficiency in Blue Devices
Authors: Lee Young Hoon , Park Sunghee , Oh Jihun , Woo Seung‐Je , Kumar Ajay , Kim Jang‐Joo , Jung Jaehoon , Yoo Seunghyup , Lee Min Hyung 
Published: June 2018

AbstractA novel approach to highly efficient, blue thermally activated delayed fluorescent (TADF) emitters is proposed. A series of ortho‐carbazole‐appended triarylboron compounds (1–5) are prepared with various substituents, including tert‐Bu, Me, and OMe, introduced to the carbazole donor and/or to the dimesitylphenylboron (PhBMes2) acceptor. Depending on the substituents on the donor and/or acceptor moieties, the emission color is finely tuned over the entire blue region from sky blue to ultradeep blue. Retention of a twisted donor (D)–acceptor (A) structure enabled by the ortho D–A connectivity and bulky triarylboron leads to small energy splitting (ΔEST) between singlet and triplet excited states, resulting in very efficient TADF. High‐efficiency blue TADF organic light‐emitting diodes (OLEDs) are realized by using the proposed ortho D–A compounds as emitters. Among them, the blue OLEDs incorporating a BuCzMeoB (2) emitter exhibit a very high external quantum efficiency (EQE) of 32.8% at Commission Internationale de l'Eclairage (CIE) color coordinates of (0.135, 0.266). The high device efficiency is attributed to both the high photoluminescence quantum yield of 2 in a given host film (93%) and the high horizontal transition dipole ratio (Θ) of 0.76. Ultradeep blue OLEDs with a record‐high efficiency are also fabricated with a CzOMeoB (5) emitter, exhibiting an EQE of 14.9% at CIE coordinates of (0.151, 0.058).
Broadband Circular Polarizing Film Based on Chiral Nematic Liquid Crystals
Authors: Cao Yuanyuan , Hamad Wadood Y. , MacLachlan Mark J. 
Published: June 2018

AbstractFilms capable of broadband circular polarization of light are important for many optical applications. Owing to their intrinsic chiral nematic mesostructure, freestanding films of cellulose nanocrystals can reflect circularly polarized light, but this is typically restricted to a narrow part of the spectrum. A new micelle‐assisted self‐assembly strategy is discovered to prepare freestanding films of cellulose nanocrystals that display circularly polarized reflection across the visible spectrum. The inexpensive and simple approach distorts the chiral nematic domains with variations of helical pitches and helical axis orientations, leading to broadband polarization. This novel method may be applicable to modifying the optical properties of other chiral nematic liquid crystals, which are widely used in display technologies.
Diastereoselective Trifluoromethylation of Chiral α,β‐Unsaturated N‐tert‐Butanesulfinyl Ketimines with Ruppert‐Prakash Reagent: Asymmetric Synthesis of α‐Tertiary Trifluoromethyl Allylic Amines
Authors: Liu Peng , Lei Zhong‐Liang , Peng Ying‐Ying , Liu Zhen‐Jiang , Zhu Feng‐Qun , Liu Jin‐Tao , Wu Fanhong 
Published: June 2018

AbstractThe diastereoselective trifluoromethylation of chiral α,β‐unsaturated N‐tert‐butanesulfinyl ketimines with Ruppert‐Prakash reagent (TMSCF3) has been attained, which provided a convenient and straightforward method for the asymmetric synthesis of structurally diverse α‐tertiary trifluoromethyl allylic amines in high yields and with excellent diastereoselectivities (dr up to > 99:1). The stereochemical outcome of the present diastereoselective trifluoromethylation of the α,β‐unsaturated N‐tert‐butanesulfinyl ketimines suggested that a cyclic six‐membered transition state is involved in the reaction, which is remarkably different from that of the trifluoromethylation of N‐tert‐butanesulfinyl aldimines.magnified image
Hyperbaric Oxygen Potentiates Doxil Antitumor Efficacy by Promoting Tumor Penetration and Sensitizing Cancer Cells
Authors: Wu Xian , Zhu Yanhong , Huang Wei , Li Jingqiu , Zhang Bixiang , Li Zifu , Yang Xiangliang 
Published: June 2018

AbstractHypoxia is a fundamental hallmark of solid tumors and helps contribute to chemotherapy resistance. Hyperbaric oxygen (HBO) therapy can overcome tumor hypoxia and promote chemotherapy antitumor efficacy; however, the simultaneous administration of some conventional chemotherapies, including doxorubicin (DOX), with HBO is considered an absolute contraindication. Here, DOX‐loaded liposome (Doxil) is coadministered with HBO to assess the safety and efficacy of this combination treatment. By overcoming tumor hypoxia, HBO not only improves Doxil tumor penetration by decreasing the collagen deposition but also sensitizes tumor cells to Doxil. As a result, the combination treatment synergistically inhibits H22 tumor growth, with a tumor inhibition rate of 91.5%. The combination of HBO with Doxil shows neither extra side effects nor promotion of tumor metastasis. These results collectively reveal that the combination of HBO with Doxil is an effective and safe treatment modality. As both HBO and Doxil are routinely used, their combination could quickly translate to clinical trials for patients with hypoxic solid tumors.
Interfacial Effects of Tin Oxide Atomic Layer Deposition in Metal Halide Perovskite Photovoltaics
Authors: Palmstrom Axel F. , Raiford James A. , Prasanna Rohit , Bush Kevin A. , Sponseller Melany , Cheacharoen Rongrong , Minichetti Maxmillian C. , Bergsman David S. , Leijtens Tomas , Wang Hsin‐Ping , Bulović Vladimir , McGehee Michael D. , Bent Stacey F. 
Published: June 2018

AbstractMetal halide perovskites offer a wide and tunable bandgap, making them promising candidates for top‐cell absorbers in tandem photovoltaics. In this work, the authors aim to understand the atomic layer deposition (ALD) precursor–perovskite interactions of the tin oxide ALD system and the role of organic fullerenes at the perovskite–tin oxide interface while establishing a framework for developing alternative perovskite‐compatible ALD processes in the future. It is shown, in the case of tin oxide ALD growth with tetrakis(dimethylamino)tin(IV) and water on FA0.83Cs0.17Pb(I0.83Br0.17)3 perovskite, that perovskite stability is most sensitive to metal–organic exposure at elevated temperatures with an onset near 110 °C, resulting in removal of the formamidinium cation. Transitioning from ALD to pulsed‐chemical vapor deposition tin oxide growth can minimize the degradation effects. Investigation of fullerenes at the perovskite interface shows that thin fullerene layers offer minor improvements to perovskite stability under ALD conditions, but significant enhancement in carrier extraction. Fullerene materials are undesirable due to fabrication cost and poor mechanical stability. Compositional tuning of the perovskite material can improve the fullerene‐free device performance. This method is demonstrated with a bromine‐rich perovskite phase to enable an 8.2% efficient perovskite device with all‐inorganic extraction layers.
Mapping Nonfullerene Acceptors with a Novel Wide Bandgap Polymer for High Performance Polymer Solar Cells
Authors: Liao Xunfan , Yao Zhaoyang , Gao Ke , Shi Xueliang , Zuo Lijian , Zhu Zonglong , Chen Lie , Liu Feng , Chen Yiwang , Jen Alex K.‐Y. 
Published: June 2018

AbstractA new weak electron‐deficient building block, bis(2‐ethylhexyl) 2,5‐bis(5‐bromothiophen‐2‐yl) thieno[3,2‐b]thiophene‐3,6‐dicarboxylate (TT‐Th), is incorporated to construct a wide‐bandgap (1.88 eV) polymer PBDT‐TT for nonfullerene polymer solar cells (NF‐PSCs). PBDT‐TT possesses suitable energy levels and complementary absorption when blended with both ITIC analogues (ITIC and IT‐M) and a near‐infrared (NIR) acceptor (6TIC). Moreover, PBDT‐TT exhibits good conjugated planarity and preferable face‐on orientation in the blended thin film, which are beneficial for charge transfer and carrier transport. The PSCs based on PBDT‐TT:IT‐M and PBDT‐TT:6TIC blend films yield high power conversion efficiencies of 11.38% and 11.03%, respectively. To the best of the authors' knowledge, the PCE of 11.03% for PBDT‐TT:6TIC‐based device is one of the highest values reported for NIR NF‐PSCs. This work demonstrates that TT‐Th is a useful new electron‐accepting building block for making p‐type wide bandgap polymers for efficient NIR NF‐PSCs.
Ir‐Catalyzed Enantioselective Intra‐ and Intermolecular Formal C−H Conjugate Addition to β‐Substituted α,β‐Unsaturated Esters
Authors: Shibata Takanori , Kurita Hisaki , Onoda Sahoko , Kanyiva Kyalo Stephen 
Published: June 2018

AbstractAn enantioselective intramolecular formal C−H conjugate addition of 4‐methyl 1‐aryl 2‐methylfumarates proceeded using a chiral iridium catalyst. A benzoylamide group served as a directing group, and chiral γ‐lactones with a quaternary all‐carbon stereogenic center were obtained with up to excellent ee. In the intermolecular reaction of N‐arylbenzamides with β‐substituted acrylates, C−H bond activation selectively occurred at the ortho‐position of carbonyl groups, and highly enantioselective formal C−H conjugate addition proceeded.
Nanofluidic Ion Transport and Energy Conversion through Ultrathin Free‐Standing Polymeric Carbon Nitride Membranes
Authors: Xiao Kai , Giusto Paolo , Wen Liping , Jiang Lei , Antonietti Markus 
Published: June 2018

AbstractIons transport through confined space with characteristic dimensions comparable to the Debye length has many applications, for example, in water desalination, dialysis, and energy conversion. However, existing 2D/3D smart porous membranes for ions transport and further applications are fragile, thermolabile, and/or difficult to scale up, limiting their practical applicability. Now, polymeric carbon nitride alternatively allows the creation of an ultrathin free‐standing carbon nitride membrane (UFSCNM), which can be fabricated by simple CVD polymerization and exhibits excellent nanofluidic ion‐transport properties. The surface‐charge‐governed ion transport also endows such UFSCNMs with the function of converting salinity gradients into electric energy. With advantages of low cost, facile fabrication, and the ease of scale up while supporting high ionic currents, UFSCNM can be considered as an alternative for energy conversion systems and new ionic devices.
A Fluorescent G‐Quadruplex Sensor for Chemical RNA Copying
Authors: Giurgiu Constantin , Wright Tom H. , O'Flaherty Derek K. , Szostak Jack W. 
Published: June 2018

AbstractNon‐enzymatic RNA replication may have been one of the processes involved in the appearance of life on Earth. Attempts to recreate this process in a laboratory setting have not been successful thus far, highlighting a critical need for finding prebiotic conditions that increase the rate and the yield. Now a highly parallel assay for template directed RNA synthesis is presented that relies on the intrinsic fluorescence of a 2‐aminopurine modified G‐quadruplex. The application of the assay to examine the combined influence of multiple variables including pH, divalent metal concentrations and ribonucleotide concentrations on the copying of RNA sequences is demonstrated. The assay enables a direct survey of physical and chemical conditions, potentially prebiotic, which could enable the chemical replication of RNA.
Switching the Statistical C3/C1 Ratio in the Threefold Aromatic Substitution of Tribenzotriquinacenes towards the C3 Isomer
Authors: Wagner Philippe , Rominger Frank , Mastalerz Michael 
Published: June 2018

AbstractTribenzotriquinacene (TBTQ) is a bowl‐shaped molecule that has been widely used as a molecular building block in supramolecular and materials chemistry. Especially C3‐symmetric threefold‐substituted TBTQs are interesting for these purposes. Until now a general and selective synthetic approach to those C3‐symmetric products was lacking, mainly because the typically used electrophilic aromatic substitution reactions of the parent TBTQ hydrocarbons produce predominantly the C1 isomer over the C3 isomer (3:1 statistical ratio). Herein we introduce a threefold borylation of TBTQ with the C3 isomer as the main product (2.6:1 C3/C1 ratio). The borylated TBTQ can be converted in good yields into other C3‐symmetric TBTQs, thus allowing straightforward synthetic access to new building blocks for supramolecular and materials chemistry.
Prevalence and Characteristics of Persistent Clonal T Cell Large Granular Lymphocyte Expansions in Rheumatoid Arthritis
Authors: Schwaneck Eva C. , Renner Regina , Junker Lara , Einsele Hermann , Gadeholt Ottar , Geissinger Eva , Kleinert Stefan , Gernert Michael , Tony Hans‐Peter , Schmalzing Marc 
Published: June 2018

ObjectiveUp to one‐third of patients with T cell large granular lymphocyte (T‐LGL) leukemia display symptoms of rheumatoid arthritis (RA). In Crohn's disease and psoriasis, treatment with tumor necrosis factor (TNF) inhibitors is associated with hepatosplenic γδ T cell lymphoma and with clonal expansion of γδ T cells, respectively. This study was undertaken to determine the prevalence of clonal T‐LGL cells in patients with RA and define risk factors for this rare hematologic malignancy.MethodsA total of 529 RA patients were recruited between November 2013 and August 2015. Eight‐color flow cytometry (fluorescence‐activated cell sorting [FACS]) was performed to screen for aberrant T cell populations of LGLs. Molecular analysis of the T cell receptor was used to confirm the diagnosis in patients with suggestive FACS findings. Electronic patient files were used to determine risk factors. Patients with clonal populations were monitored prospectively for up to 4 years.ResultsThe median patient age was 61 years, and 74% were female. The median duration of RA was 12 years. The median Disease Activity Score in 28 joints was 2.8, and 69.9% of patients had ever been treated with biologic disease‐modifying antirheumatic drugs. We identified clonal T‐LGL expansions in 19 patients, equaling a prevalence of 3.6%. The T‐LGL cell clone was constant over time in most patients and was significantly associated with the duration of the exposure to TNF‐blocking agents (P = 0.01). No other risk factors could be detected.ConclusionRA patients with long‐term exposure to TNF‐blocking agents were at a greater risk of developing clonal expansions of LGLs. This finding may prompt clinicians to refrain from using these substances in RA patients with known T cell aberrations.
The Red‐/Green‐Switching GAF3 of Cyanobacteriochrome Slr1393 from Synechocystis sp. PCC6803 Regulates the Activity of an Adenylyl Cyclase
Authors: Hu Ping‐Ping , Guo Rui , Zhou Ming , Gärtner Wolfgang , Zhao Kai‐Hong 
Published: June 2018

AbstractCyanobacteriochromes (CBCRs) are photoreceptors in cyanobacteria that present a bilin chromophore‐binding GAF domain as a photochromic element to control the activity of a downstream enzyme or regulator. CBCR Slr1393 from Synechocystis PCC 6803 carries three GAF domains, but only the third one binds phycocyanobilin covalently. Slr1393 shows photochromicity between red and green absorbing states and regulates a C‐terminally located histidine kinase. In this work, we fused this third GAF domain to an adenylyl cyclase (AC) from Microcoleus chthonoplastes PCC7420 that in its genuine form is under blue‐light control from a LOV domain. A series of RGS‐AC variants were constructed with various lengths of the linkers between RGS and AC. Assays in vitro and in living Escherichia coli cells (AC‐deletion mutant) demonstrated that the activity of AC was light regulated, namely, the red‐light‐converted form of RGSΔ14‐Δ4AC (in vitro) was about three times more active than the green‐light‐converted form. Expression of the fusion protein RGSΔ14‐Δ4AC in vivo again showed highest light regulation with at least threefold amplification of the AC function. In some experiments, even tenfold higher activity was observed, which indicated that the protein, if expressed under in vivo conditions, was part of the E. coli physiological conditions and thereby subjected to more complex and variable regulation through other E. coli inherent factors.
Enhanced BTX Production in Refineries with Sulfur Dioxide Oxidation by Thermal Integrated Model
Authors: Karimi Mohsen , Rahimpour Mohammad Reza , Iranshahi Davood 
Published: June 2018

AbstractMore stringent environmental regulations as well as limitations of traditional energy sources lead to the development of innovative techniques to supply the required energy of different industries. Multifunctional autothermal reactors as a novel strategy in process integration technology have been introduced as a response to this requirement. The catalytic naphtha reforming process is one of the main processes in the refinery industries which demand several sources of energy to manage the existing reactions. Also, oxidization of sulfur dioxide to sulfur trioxide as a highly exothermic reaction is one of the typical solutions to reduce and control this greenhouse gas in various industries. According to the main aims of process integration and by considering environmental regulations, a novel thermal integration model is proposed. The results demonstrate the aromatic upgrading and high conversion of sulfur dioxide in this model.