bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effectiveness of Moving Signal‐Average Method in K Band FMCW Radar for Short‐Range Vehicle Detection Using Antennas With Narrow Beam Widths
Authors: Chou Hsi‐Tseng , Ho Hsien‐Kwei , Chang Tsang‐Pin 
Published: March 2018

AbstractThis paper presents the implementation and examination of moving signal‐average methods (MSAMs) to improve the defects of frequency‐modulated continuous wave (FMCW) radar in detecting short‐range vehicles which may cause false target detection. The MSAM may smooth out the short‐term signal fluctuations in the system responses of received data in time series. These signal fluctuations may appear when the antenna radiation has a narrow beam width to illuminate only a part of sophisticated vehicle structures. In this examination, the defect phenomena were first investigated by employing the electromagnetic backscattering simulation. Afterward, experimental measurements were performed by implementing MSAM in a radar system for side‐looking vehicle detection. The experimental FMCW radar operates at 24.125 GHz with 250 MHz bandwidth and implements a linear frequency modulation for transmitter/receiver with 2 mW for transmitter power. The output responses to determine the detection are based on the peak value distribution of signals after being processed by the fast Fourier transform and MSAM. Both numerical simulations and experiments have demonstrated the validity of MSAM in the signal treatment to detect the vehicles within the coverage range.
Relationship Between the Electromagnetic Wave Energy Coupled by Overhead Lines and the Radiation Source Current Explored in the Laboratory
Authors: Li Xiangchao , Wan Zhicheng 
Published: March 2018

AbstractIn order to solve the damage and interference problems to the electronic devices, which are induced by overvoltage excited by the coupling process between lightning electromagnetic wave and overhead lines, the lightning channel is set to be equivalent to a radiant wire antenna. Based on the integration model of lightning return stroke channel, transmission line, and ground, we take advantage of the derived formula gotten from the transmission line model. By combing the theoretical and experimental methods, we conduct a comparative analysis on the coupling process between natural/simulated lightning and overhead line. Besides, we also calculate the amplitude and energy of overvoltage, which is caused by the coupling process between lightning electromagnetic wave and overhead lines. Upon these experimental results, we can draw several conclusions as follows: when the amplitude of the lightning current in the channel is between 5 kA and 41 kA, it takes on an excellent linear relation between the amplitude of overvoltage and the magnitude of the lightning current, the relation between coupling energy and magnitude of the lightning current takes on an exponential trend. When lightning wave transmits on the transmission lines, the high‐order mode will be excited. Through analysis on the high‐order mode's characteristics, we find that the theoretical analysis is consistent with the experimental results, which has a certain reference value to the protection on overhead lines.
Thermomechanically Triggered Two‐Stage Pattern Switching of 2D Lattices for Adaptive Structures
Authors: Yuan Chao , Mu Xiaoming , Dunn Conner K. , Haidar Jamal , Wang Tiejun , Jerry Qi H. 
Published: March 2018

AbstractPattern switching (or transformation) widely exists in the activities of various creatures and plays an important role in designing adaptive structures in modern materials. Utilizing the glass transition behavior in amorphous polymers, thermomechanically triggered two‐stage pattern switching of 2D lattices is achieved, where components made of an amorphous polymer and a flexible elastomer are interconnected in predesigned layouts. Upon loading at room temperature, the elastomer is far more flexible than the amorphous polymer and the lattice switches into one pattern. With temperature increasing, the modulus of the amorphous polymer decreases due to glass transition. Under the proper choice of amorphous polymer whose storage modulus can decrease to below the modulus of the elastomer, a change in the relative stiffness can be achieved and can switch the overall pattern from one to another while maintaining the external load. Both the experimental and computational studies are carried out to investigate the switching mechanism. Several periodic structures are fabricated to demonstrate several switched patterns. Particularly, a proof‐of‐concept smart window design is fabricated to explore the potential engineering applications.
Encapsulating Various Sulfur Allotropes within Graphene Nanocages for Long‐Lasting Lithium Storage
Authors: Yuan Yifei , Tan Guoqiang , Wen Jianguo , Lu Jun , Ma Lu , Liu Cong , Zuo Xiaobing , Shahbazian‐Yassar Reza , Wu Tianpin , Amine Khalil 
Published: March 2018

AbstractThe encapsulation of sulfur within carbon matrices is widely utilized in the cathode of a rechargeable lithium–sulfur battery, whose energy density largely depends on the design of the carbon structure. Here, an advanced graphene nanocage structure with the capability of hosting both cyclo‐S8 and smaller sulfur molecules (S2–4) is reported. The cage inner cavity is partially filled with S8 to form a yolk–shell structure that enables free volumetric variation of S8 during (de)lithiation. In the graphene shell of the cage, S8 are downsized to S2–4 to activate extra sulfur loading sites within graphene layers. Importantly, the graphene shell exhibits inward volumetric variation upon (de)lithiation of the loaded S2–4, and the overall electrode strain is thus minimized. This prototyped design promises an ultimate solution to maximize sulfur loading in carbon matrices as well as to circumvent the polysulfide dissolution problem and boost the commercialization of lithium‐sulfur batteries in the future.
2D Chiroptical Nanostructures for High‐Performance Photooxidants
Authors: Xu Liguang , Sun Maozhong , Cheng Ping , Gao Rui , Wang Hui , Ma Wei , Shi Xinghua , Xu Chuanlai , Kuang Hua 
Published: March 2018

AbstractModulation of the chirality of solid‐like nanoscale membranous structures used as selective photooxidants is an important goal of chemical and materials science. Here, the fabrication of a chiral plasmonic nanoparticle monolayer film which is a highly selective photooxidant under circularly polarized light (CPL) in the visible‐light region is reported. The chiroptical activity of the film can be controlled by altering the amount and stereochemistry of amino acids. The experiments disclose that this stable and reusable catalyst is active in the selective oxidation of glucose enantiomers and CPL of opposite polarization gives around 10.3‐fold increase in conversion rates. The results reveal that the handedness of polarized light dominates the catalytic activity of the chiral film. It is demonstrated that the specific chiral binding of the amino acid ligands and the local field enhancement in the light‐limited regime regulates the selective photocatalytic performance, as confirmed by first‐principles density functional theory and physical field simulations. With the catalyst's signature ability for chiral recognition and switching of handedness of polarized light, the discovery provides a foundation for designing and tailoring chiral inorganic photooxidants. This research also sets an example for the development of light–matter interactions and polarized optics.
Exploring Critical Factors Affecting Strain Distribution in 1D Silicon‐Based Nanostructures for Lithium‐Ion Battery Anodes
Authors: Son Yoonkook , Sim Soojin , Ma Hyunsoo , Choi Min , Son Yeonguk , Park Noejung , Cho Jaephil , Park Minjoon 
Published: March 2018

AbstractDespite the advantage of high capacity, the practical use of the silicon anode is still hindered by large volume expansion during the severe pulverization lithiation process, which results in electrical contact loss and rapid capacity fading. Here, a combined electrochemical and computational study on the factor for accommodating volume expansion of silicon‐based anodes is shown. 1D silicon‐based nanostructures with different internal spaces to explore the effect of spatial ratio of voids and their distribution degree inside the fibers on structural stability are designed. Notably, lotus‐root‐type silicon nanowires with locally distributed void spaces can improve capacity retention and structural integrity with minimum silicon pulverization during lithium insertion and extraction. The findings of this study indicate that the distribution of buffer spaces, electrochemical surface area, as well as Li diffusion property significantly influence cycle performance and rate capability of the battery, which can be extended to other silicon‐based anodes to overcome large volume expansion.
On‐Surface Synthesis of Carbon Nanostructures
Authors: Sun Qiang , Zhang Renyuan , Qiu Jun , Liu Rui , Xu Wei 
Published: March 2018

AbstractNovel carbon nanomaterials have aroused significant interest owing to their prospects in various technological applications. The recently developed on‐surface synthesis strategy provides a route toward atomically precise fabrication of nanostructures, which paves the way to functional molecular nanostructures in a controlled fashion. A plethora of low‐dimensional nanostructures, challenging to traditional solution chemistry, have been recently fabricated. Within the last few decades, an increasing interest and flourishing studies on the fabrication of novel low‐dimensional carbon nanostructures using on‐surface synthesis strategies have been witnessed. In particular, carbon materials, including fullerene, carbon nanotubes, and graphene nanoribbons, are synthesized with atomic precision by such bottom‐up methods. Herein, starting from the basic concepts and progress made in the field of on‐surface synthesis, the recent developments of atomically precise fabrication of low‐dimensional carbon nanostructures are reviewed.
Polymer on Top: Current Limits and Future Perspectives of Quantitatively Evaluating Surface Grafting
Authors: Michalek Lukas , Barner Leonie , Barner‐Kowollik Christopher 
Published: March 2018

AbstractWell‐defined polymer strands covalently tethered onto solid substrates determine the properties of the resulting functional interface. Herein, the current approaches to determine quantitative grafting densities are assessed. Based on a brief introduction into the key theories describing polymer brush regimes, a user's guide is provided to estimating maximum chain coverage and—importantly—examine the most frequently employed approaches for determining grafting densities, i.e., dry thickness measurements, gravimetric assessment, and swelling experiments. An estimation of the reliability of these determination methods is provided via carefully evaluating their assumptions and assessing the stability of the underpinning equations. A practical access guide for comparatively and quantitatively evaluating the reliability of a given approach is thus provided, enabling the field to critically judge experimentally determined grafting densities and to avoid the reporting of grafting densities that fall outside the physically realistic parameter space. The assessment is concluded with a perspective on the development of advanced approaches for determination of grafting density, in particular, on single‐chain methodologies.
Balanced Partnership between Donor and Acceptor Components in Nonfullerene Organic Solar Cells with >12% Efficiency
Authors: Lin Yuze , Zhao Fuwen , Prasad Shyamal K. K. , Chen Jing‐De , Cai Wanzhu , Zhang Qianqian , Chen Kai , Wu Yang , Ma Wei , Gao Feng , Tang Jian‐Xin , Wang Chunru , You Wei , Hodgkiss Justin M. , Zhan Xiaowei 
Published: March 2018

AbstractRelative to electron donors for bulk heterojunction organic solar cells (OSCs), electron acceptors that absorb strongly in the visible and even near‐infrared region are less well developed, which hinders the further development of OSCs. Fullerenes as traditional electron acceptors have relatively weak visible absorption and limited electronic tunability, which constrains the optical and electronic properties required of the donor. Here, high‐performance fullerene‐free OSCs based on a combination of a medium‐bandgap polymer donor (FTAZ) and a narrow‐bandgap nonfullerene acceptor (IDIC), which exhibit complementary absorption, matched energy levels, and blend with pure phases on the exciton diffusion length scale, are reported. The single‐junction OSCs based on the FTAZ:IDIC blend exhibit power conversion efficiencies up to 12.5% with a certified value of 12.14%. Transient absorption spectroscopy reveals that exciting either the donor or the acceptor component efficiently generates mobile charges, which do not suffer from recombination to triplet states. Balancing photocurrent generation between the donor and nonfullerene acceptor removes undesirable constraints on the donor imposed by fullerene derivatives, opening a new avenue toward even higher efficiency for OSCs.
Terpene‐Derived Highly Branched C30‐Amines via Palladium‐Catalysed Telomerisation of β‐Farnesene
Authors: Vogelsang Dennis , Faßbach Thiemo A. , Kossmann Paul P. , Vorholt Andreas J. 
Published: March 2018

AbstractThe synthesis of highly branched long chain amines in one step is still a challenge. The palladium catalysed telomerisation of the renewable sesquiterpene β‐farnesene with secondary amines yields such tertiary amines and thus, was investigated within this work. Preliminary, a suitable palladium catalyst system was developed by a high‐throughput screening. It efficiently allows for the synthesis of tertiary amines with a highly branched C30‐carbon chain with yields up to 94% of the corresponding desired allylic C30‐amines. The generality of the protocol was proven for thirteen amines with linear and branched alkyl and aryl groups. A clear correlation between the scaffold of the amine, basicity and the activity as nucleophile in the telomerisation was uncovered. Based on the different polarities of the nonpolar in‐situ formed C30‐substituted tertiary amines and the polar solvent, a proof of concept for catalyst recovery by simple decantation was shown.magnified image
Mean Streets and Mental Health: Depression and Post‐Traumatic Stress Disorder at Crime Hot Spots
Authors: Weisburd David , Cave Breanne , Nelson Matthew , White Clair , Haviland Amelia , Ready Justin , Lawton Brian , Sikkema Kathleen 
Published: March 2018

AbstractThis study explores the relationship between mental health and place at microgeographic units of analysis. We examine self‐reported symptomology for depression and PTSD for 2,724 survey respondents interviewed in three types of randomly selected street segments: violent crime hot spots, cool spots, and cold spots. We find that the mean symptomology score is 61% higher for depression in violent crime hot spots than cold spots, and 85% higher for PTSD. Overall, we estimate that 14.8% of residents of violent crime hot spots meet thresholds for moderate depression or a diagnosis of PTSD. This can be compared to only 6.5% of residents at the cold spots. Using PSM and weighted negative binomial regression approaches we show that observable selection factors are not responsible for the relationships identified. Examining geographic influences, we find an important area effect of violent crime for both mental health measures, and an additional impact of the specific street of residence for PTSD.
Chronic neutrophilic leukemia: 2018 update on diagnosis, molecular genetics and management
Authors: Elliott Michelle A. , Tefferi Ayalew 
Published: March 2018

AbstractDisease Overview and DiagnosisChronic neutrophilic leukemia (CNL) is a potentially aggressive myeloproliferative neoplasm, for which current WHO diagnostic criteria include leukocytosis of ≥ 25 x 109/L of which ≥ 80% are neutrophils, with < 10% circulating neutrophil precursors with blasts rarely observed. In addition, there is no dysplasia, nor clinical or molecular criteria for other myeloproliferative neoplasms.Update on DiagnosisPreviously the diagnosis of CNL was often as one of exclusion based on no identifiable cause for physiologic neutrophilia in patients fulfilling the aforementioned criteria. The 2016 WHO classification now recognizes somatic activating mutations of CSF3R (most commonly CSF3RT618I) as diagnostic, allowing for an accurate diagnosis for the majority of suspected cases through molecular testing. These mutations are primary driver mutations, accounting for the characteristic clinical phenotype and potential susceptibility to molecularly targeted therapy.Risk StratificationConcurrent mutations, common to myeloid neoplasms and their precursor states, most frequently in SETBP1 and ASXL1, are frequent and appear to be of prognostic significance. Although data are evolving on the full genomic profile, the rarity of CNL has delayed complete understanding of its full molecular pathogenesis and individual patient prognosis.
Universal Distributed Quantum Computing on Superconducting Qutrits with Dark Photons
Authors: Hua Ming , Tao Ming‐Jie , Alsaedi Ahmed , Hayat Tasawar , Deng Fu‐Guo 
Published: March 2018

AbstractA one‐step scheme is presented to construct the controlled‐phase gate deterministically on remote transmon qutrits coupled to different resonators connected by a superconducting transmission line for an universal distributed quantum computing. Different from previous work on remote superconducting qubits, the present gate is implemented with coherent evolutions of the entire system in the all‐resonance regime assisted by the dark photons to robust against the transmission line loss, which allows the possibility of the complex designation of a long‐length transmission line to link lots of circuit QEDs. The length of the transmission line can reach the scale of several meters, which makes this scheme suitable for large‐scale distributed quantum computing. This gate is a fast quantum entangling operation with a high fidelity of about 99%. Compared with previous work in other quantum systems for a distributed quantum computing, under the all‐resonance regime, the present proposal does not require classical pulses and ancillary qubits, which relaxes the difficulty of its implementation largely.
A Multi‐signal Fluorescent Probe with Multiple Binding Sites for Simultaneous Sensing of Cysteine, Homocysteine, and Glutathione
Authors: Yin Guo‐xing , Niu Ting‐ting , Gan Ya‐bing , Yu Ting , Yin Peng , Chen Hai‐min , Zhang You‐yu , Li Hai‐tao , Yao Shou‐zhuo 
Published: March 2018

AbstractA novel fluorescent probe was developed by integrating chlorinated coumarin and benzothiazolylacetonitrile and exploited for simultaneous detection of cysteine (Cys), homocysteine (Hcy), and glutathione (GSH). Featuring four binding sites and different reaction mechanisms for different biothiols, this probe exhibited rapid fluorescence turn‐on for distinguishing Cys, Hcy, and GSH with 108‐, 128‐, 30‐fold fluorescence increases at 457, 559, 529 nm, respectively, across different excitation wavelengths. Furthermore, the probe was successfully applied to the fluorescence imaging of endogenous Cys and GSH and exogenous Cys, Hcy, and GSH in living cells.
An Easily Accessible Ionic Aggregation‐Induced Emission Luminogen with Hydrogen‐Bonding‐Switchable Emission and Wash‐Free Imaging Ability
Authors: Chen Yuncong , Zhang Weijie , Zhao Zheng , Cai Yuanjing , Gong Junyi , Kwok Ryan T. K. , Lam Jacky W. Y. , Sung Herman H. Y. , Williams Ian D. , Tang Ben Zhong 
Published: March 2018

AbstractIonic fluorophores are powerful tools for the study of environmental science and bio‐imaging. However, traditional ionic dyes usually require long synthetic steps and suffer from a quenching effect caused by aggregation. A water‐soluble ionic aggregation‐induced emission luminogen called DBTA is presented, which is readily accessed by a one‐step reaction. The switchable emission manipulated by hydrogen bonding provided solid evidence for the restriction of intramolecular motions as the mechanism of aggregation‐induced emission. DBTA can not only differentiate solvents with different H‐bond donor acidities but also capable of wash‐free imaging in living HeLa cells and fish larva.
Decarboxylative Benzylation of Aryl and Alkenyl Boronic Esters
Authors: Moon Patrick J. , Fahandej‐Sadi Anis , Qian Wenyu , Lundgren Rylan J. 
Published: March 2018

AbstractThe copper‐catalyzed decarboxylative benzylation of aryl and alkenyl boronic esters with electron‐deficient aryl acetates is reported. The oxidative coupling proceeds under mild, aerobic conditions and tolerates a host of potentially reactive electrophilic functional groups that would be problematic with traditional benzylation methods (aryl iodides and bromides, protic heteroatoms, aldehydes, Michael acceptors). A reaction pathway in which a benzylic nucleophile is generated by aryl acetate decarboxylation and in turn is intercepted by the catalyst to form diarylmethane products is supported by mechanistic studies.
Pb2BO3I: A Borate Iodide with the Largest Second‐Harmonic Generation (SHG) Response in the KBe2BO3F2 (KBBF) Family of Nonlinear Optical (NLO) Materials
Authors: Yu Hongwei , Koocher Nathan Z. , Rondinelli James M. , Halasyamani P. Shiv 
Published: March 2018

AbstractBorate halides are an ideal materials class from which to design high‐performance nonlinear optical (NLO) materials. Currently, borate fluorides, chlorides, and bromides are extensively investigated while borate iodide materials discovery remains rare because of the perceived synthetic challenges. We report a new borate iodide, Pb2BO3I, synthesized by a straightforward hydrothermal method. The Pb2BO3I chemical formula conceals that the compound exhibits a structure similar to the well‐established KBe2BO3F2 (KBBF), which we show supports the highest second‐harmonic generation (SHG) at 1064 nm in the KBBF family, 10 × KH2PO4 (KDP), arising from the inclusion of Pb2+ and I− and the crystal chemistry. Our work shows that KBBF‐related compounds can be synthesized incorporating iodide and exhibit superior NLO responses.
The Use of Ultrasound in pipette‐tip solid‐phase extraction based on CuS@ZnS@Fe3O4‐CNTs for pre‐concentration of tartrazine in water samples
Authors: Ostovan Abbas , Asadollahzadeh Hamideh , Ghaedi Mehrorang 
Published: March 2018

This paper report a novel strategy for synthesis and application of CuS@ZnS@Fe3O4‐CNTs composite which has great potentials as artificial receptor for tartrazine trapping due to its ultrahigh surface area and functionality which is related to application of electrochemical route. A durable and economical pipette‐tip CuS@ZnS@Fe3O4‐CNTs nano‐composite miniaturized solid phase extraction coupled with UV‐Vis spectrophotometry was developed for clean‐up and determination of tartrazine from various water samples. Undoubtedly, presence of mild‐intensity/frequency ultrasound irradiation played a key role for reducing consumption of eluent volume by broking hydrogen bonds between retained analyte and sorbent. The influence of factors including pH, sorbent dosage, sonication time and eluent volume were investigated and optimum conditions were obtained using experimental design methodology. Under optimized conditions, good extraction efficiencies for the analyte were obtained with no matrix interference in the subsequent UV‐Vis. Good linearity for tartrazine in the range of 20‐5000 ng mL‐1 with correlation coefficients of R2 ≥ 0.99 and low detection limit close to 4.76 ng mL‐1 reveals high applicability of method for trace analysis.