bluuebunny/crossref_metadata_2025_split huggingface dataset:
Selective Defect Formation in Hexagonal Boron Nitride
Authors: Abidi Irfan H. , Mendelson Noah , Tran Toan Trong , Tyagi Abhishek , Zhuang Minghao , Weng Lu‐Tao , Özyilmaz Barbaros , Aharonovich Igor , Toth Milos , Luo Zhengtang 
Published: May 2019

AbstractLuminescent defects in hexagonal boron nitride (hBN) have emerged as promising single photon emitters (SPEs) due to their high brightness and robust operation at room temperature. The ability to create such emitters with well‐defined optical properties is a cornerstone toward their integration into on‐chip photonic architectures. Here, an effective approach is reported to fabricate hBN SPEs with desired emission properties in distinct spectral regions via the manipulation of boron diffusion through copper during atmospheric pressure chemical vapor deposition (CVD)—a process termed gettering. Using the gettering technique the resulting zero‐phonon line is deterministically placed between the regions 550 and 600 nm or from 600 to 650 nm, paving the way for hBN SPEs with tailored emission properties. Additionally, rational control over the observed SPE density in the resulting films is demonstrated. The ability to control defect formation during hBN growth provides a cost effective means to improve the crystallinity of CVD hBN films, and lower defect density making it applicable to hBN growth for a wide‐range of applications. The results are important to understand defect formation of quantum emitters in hBN and deploy them for scalable photonic technologies.
Reduced Local Symmetry in Lithium Compound Li2SrSiO4 Distinguished by an Eu3+ Spectroscopy Probe
Authors: Chen Lei , Cheng Peng , Zhang Zhao , He Liangrui , Jiang Yang , Li Guobao , Jing Xiping , Qin Yan'guang , Yin Min , Chan Ting‐Shan , Hong Bin , Tao Shi , Chu Wangsheng , Zhao Zhi , Ni Haiyong , Kohlmann Holger , Oeckler Oliver 
Published: May 2019

AbstractResearch on lithium compounds has attracted much attention nowadays. However, to elucidate the precise structure of lithium compounds is a challenge, especially when considering the small ions that may be transferred between the interstitial voids. Here, the discovery of reduced local symmetry (symmetry breaking) in small domains of Li2SrSiO4 is reported by employing Eu3+ as a spectroscopic probe, for which X‐ray, neutron, and electron diffraction have confirmed the average long‐range structure with the space group P3121. However, luminescence shows a lower local symmetry, as confirmed by the extended X‐ray absorption fine structure. By considering the reduced symmetry of the local structure, this work opens the door to a new class of understanding of the properties of materials.
New Metallic Ordered Phase of Perovskite CsPbI3 under Pressure
Authors: Liang Yongfu , Huang Xiaoli , Huang Yanping , Wang Xin , Li Fangfei , Wang Youchun , Tian Fubo , Liu Bingbing , Shen Ze Xiang , Cui Tian 
Published: May 2019

AbstractPressure‐induced electronic structure transition from insulating phase to metal state is a potential new paradigm for halide perovskites. The metallization based on these materials may afford a novel motif toward realizing new electronic properties even superconductivity phenomenon. Herein, how static compression modulates the crystal and electronic structure of typical perovskite semiconductors cesium lead iodine (CsPbI3) by both experimental and theoretical studies is reported. The comprehensive studies discover the insulator–metal transition of CsPbI3 at 39.3 GPa, and reveal the key information behind the electronic transition. The perovskite's precise structural evolution is tracked upon compression, from orthorhombic Pnma phase to monoclinic C2/m structure before the metallic transition. More interestingly, the C2/m phase has the most distorted octahedra and the shortest Pb–I bond length relative to the average bond length that is ever reported in a halide perovskite structure. The electronic transition stems from the structural changes accompanied by the anomalously self‐distorted octahedra. These studies show that pressure can significantly alter the structural and electronic properties of these technologically important perovskites.
Surgical outcomes of gastroenterological surgery in Japan: Report of the National Clinical Database 2011‐2017
Authors: Hasegawa Hiroshi , Takahashi Arata , Kakeji Yoshihiro , Ueno Hideki , Eguchi Susumu , Endo Itaru , Sasaki Akira , Takiguchi Shuji , Takeuchi Hiroya , Hashimoto Masaji , Horiguchi Akihiko , Masaki Tadahiko , Marubashi Shigeru , Yoshida Kazuhiro , Konno Hiroyuki , Gotoh Mitsukazu , Miyata Hiroaki , Seto Yasuyuki 
Published: May 2019

AbstractBackgroundThe Japanese National Clinical Database (NCD) is a large‐scale, nationwide, web‐based data entry system that is linked to the surgical board certification system and covers almost all surgical cases carried out in Japan.AimTo evaluate outcomes according to the gastroenterological section of the NCD.MethodsThe 115 surgical procedures stipulated by the “Training Curriculum for Board‐Certified Surgeons in Gastroenterology” were registered from 2011 to 2017. The number of surgeries, preoperative comorbidities, and short‐term outcomes were compared between registration periods.ResultsIn total, 3 818 414 cases have been registered. More than 70% of all surgeries were carried out at certified institutions. The annual number of cases has been increasing year after year, and the aged population has also been increasing. Although the rates of preoperative comorbidities and postoperative complications have been increasing, the postoperative mortality rate has remained relatively low; in 2017, the 30‐day mortality rate was 1.0% among those who underwent esophagectomy, 0.7% among those who underwent distal gastrectomy, 1.1% among those who underwent total gastrectomy, 1.3% among those who underwent right hemicolectomy, 0.5% among those who underwent low anterior resection, 1.3% among those who underwent hepatectomy, and 1.3% among those who underwent pancreaticoduodenectomy. The annual rate of endoscopic surgery dramatically increased over 7 years between 2011 and 2017, especially for low anterior resection (29.5%‐62.6%) and esophagectomy (31.0%‐56.1%).ConclusionThis database is expected to ensure the quality of the board‐certification system and surgical outcomes in gastroenterological surgery.
Experimental study of hydrate formation in oil–water systems using a high‐pressure visual autoclave
Authors: Song Guangchun , Li Yuxing , Wang Wuchang , Zhao Pengfei , Jiang Kai , Ye Xiao 
Published: May 2019

AbstractTo investigate the characteristics of hydrate formation in oil–water systems, a high‐pressure visual autoclave equipped with visual windows was used where a series of hydrate formation experiments were performed from natural gas + diesel oil + water systems at different water cuts (30 and 70%), rotation rates (100, 200, 300 r/min) and thermodynamic conditions (temperature, pressure). According to the temperature and pressure profiles in test experiments, the processes of hydrate formation under two kinds of experimental procedures were analyzed first. Then, based on the experimental phenomenon observed through the visual windows, hydrate morphologies and hydrate morphological evolvements throughout the experiments were mainly investigated. In experiments, the growth and annealing of hydrate films on the wall, the agglomeration and deposition of hydrate coated water droplets, flocculent‐like hydrate deposition with water trapped in and the Pickering effect of hydrates were identified. Simultaneously, based on the experimental data of thermodynamic parameters, the kinetics of hydrate formation was studied by calculating the variations of hydrate film area and gas consumption in different experiments. In addition, the influences of temperature, pressure, and rotation rate on hydrate morphologies, hydrate morphological evolvements, and hydrate formation kinetics were also focused on.
Quantum Interface between a Superconducting Qubit and Spin Ensembles
Authors: Zhang Feng‐Yang , Li Wen‐Lin , Yan Wei‐Bin , Yang Chui‐Ping 
Published: May 2019

AbstractAn experimentally feasible strong coupling system between a spin ensemble and a superconducting qubit is studied. The coupling strength can be exponentially enhanced by applying the squeezing transformations to the system. By means of the two spin ensembles commonly coupled to a superconducting qubit, a set of universal nonadiabatic holonomic single‐qubit quantum gates can be realized in a decoherence‐free subspace. Furthermore, this proposal is robust with respect to decay of the system parameters, and it is experimentally feasible with currently available technology.
Rhodium‐Catalyzed Parallel Kinetic Resolution of Racemic Internal Allenes Towards Enantiopure Allylic 1,3‐Diketones
Authors: Hilpert Lukas J. , Breit Bernhard 
Published: May 2019

AbstractA rare case of a parallel kinetic resolution of racemic 1,3‐disubstituted allenes by means of a rhodium‐catalyzed addition to 1,3‐diketones furnishing enantiopure allylic 1,3‐diketones is described. Mechanistic experiments demonstrate that the different allene enantiomers react in parallel to either the diastereomeric E‐ or Z‐allylic 1,3‐diketones with the same absolute configuration of the newly formed stereogenic center. A broad substrate scope demonstrates the synthetic utility of this new method.
Carnauba Wax Particles: Investigation of Dripping and Cold‐Extrusion Processes
Authors: Paulo Bruna Barbon , Schmiele Marcio , Maximo Guilherme José , Prata Ana Silvia 
Published: May 2019

AbstractSolid lipids are commonly used as carrier systems for encapsulation processes. However, formulations containing only solid lipids tend to form a highly ordered crystal lattice, which can expel the active compound during long‐term storage, due to the dynamics of polymorphic transitions. Regarding the aspects of particle production, the cooling step of the melted lipid is essential for determining the type of formed crystals. This work aimed to analyze the effects of the crystallization step on the physicochemical properties of lipid particles. Carnauba wax (CW) particles with a relatively high melting point (Tm = 78 °C) were produced by the dripping method, based on melting‐crystallization steps, and by cold extrusion, which uses temperatures lower than the melting point of the lipid. Then, the physical properties, thermal behavior, and X‐ray of CW particles were analyzed. The particles obtained by dripping and extrusion presented mean sizes of 3.7 and 1.5 mm, respectively. All particles presented a similar thermal behavior (Tm = 78 °C; ΔH = 200 J g−1) and crystalline arrangement of the lipids. However, the dripping system presented an operational problem of clogging, requiring efficient thermal insulation, whereas the extrusion is a cost‐effective, time‐saving, and eco‐friendly method.
Effect of ionic radius on soot oxidation activity for ceria‐based binary metal oxides
Authors: Anantharaman Anjana P. , Dasari Hari Prasad , Dasari Harshini , Babu G. Uday Bhaskar 
Published: May 2019

AbstractCeO2 (C) along with binary metal oxides of Ce0.9M0.1O2‐δ (M = Sn, Hf, Zr, Gd, Sm, and La; CT, CH, CZ CG, CS, and CL) are synthesized using the EDTA–citrate method. Samples having an ionic radius smaller (CT, CH, and CZ) and larger (CG, CS, and CL) than Ce4+ are classified separately, and their soot oxidation activity is analyzed. The incorporation of dopant is confirmed from lattice constant variation in X‐ray diffraction result. The critical descriptors for the activity are dopant nature (ionic radius and oxidation‐state), single‐phase solid solution, lattice strain, reactive (200) and (220) planes, Raman intensity ration (Iov/IF2g), optical bandgap, reducibility ratio, and surface oxygen vacancy. Smaller ionic radius, isovalent dopants (CH and CZ) create a defect site by lowering the optical bandgap along with improved surface oxygen vacancy concentration and thus enhanced soot oxidation activity. Aliovalent dopant with larger ionic radius shows the involvement of lattice oxygen in oxidation reaction by charge compensation mechanism. CL showed the highest activity amongst larger ionic radius samples.
Ultralight nanocomposite aerogels with interpenetrating network structure of bacterial cellulose for oil absorption
Authors: Nie Xiaolin , Lv Pengfei , Stanley Sarah L. , Wang Di , Wu Shuanglin , Wei Qufu 
Published: May 2019

ABSTRACTTowards the development of novel platforms for oil absorption and environmental remediation, bacterial cellulose aerogels (BCA), a lightweight and highly porous material, were modified with carbon nanotubes (CNT) and carboxylic carbon nanotubes (CCNT), respectively, at both 5 and 10 wt % loading. The resulting nanocomposite materials, termed BCA/CNT and BCA/CCNT, demonstrated improved oil absorption property when tested against liquid paraffin (glycerol), vacuum oil, plant oil, and propanetriol. After a single immersion lasting about 4–119 seconds, BCA/CNT 10% absorbed an average of 120.23 (standard deviation: 1.145) g·g−1of propanetriol. While BCA is known to be fragile, but no destruction was observed before and after oil absorption. The difference between CNT and CCNT is carboxylation, which could reduce hydrophilicity. The samples were characterized by scanning electron microscope (SEM), Fourier transform infrared spectrum (FTIR), Brunauer–Emmett–Teller (BET) analysis, contact angle test, and mechanical test. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 48000.
1H‐1,2,3‐Triazole tethered isatin‐moxifloxacin: Design, synthesis and in vitro anti‐mycobacterial evaluation
Authors: Jiang Yu , Qian Ailin , Li Yan 
Published: May 2019

AbstractA series of novel 1H‐1,2,3‐triazole tethered isatin–moxifloxacin (MXF) hybrids 5a‐l with greater lipophilicity compared with the parent MXF were designed, synthesized and screened for their in vitro antimycobacterial activities against Mycobacterium tuberculosis (MTB) H37Rv and multidrug‐resistant MTB (MDR–MTB) as well as their cytotoxicity on the VERO cell line. All the synthesized hybrids (MIC: 0.025‐0.78 μg/ml) showed considerable activities against MTB H37Rv and MDR–MTB, and the most active conjugate 5c (MIC: 0.025 and 0.06 μg/ml) was 2 to >2048 times more potent in vitro than the three references MXF (MIC: 0.10 and 0.12 μg/ml), rifampicin (MIC: 0.39 and 32 μg/ml) and isoniazid (MIC: 0.05 and >128 μg/ml) against the two tested strains. All hybrids (CC50: 4‐64 μg/ml) were much more cytotoxic than the parent MXF (CC50: 128 μg/ml), but the most active hybrid 5c (CC50: 32 μg/ml) also displayed acceptable cytotoxicity, warranting further investigation.
Unmanned aerial vehicle and structure‐from‐motion photogrammetry for three‐dimensional documentation and digital rubbing of the Zuo River Valley rock paintings
Authors: Wang Shaohua , Wang Yue , Hu Qingwu , Li Jiayuan , Ai Mingyao 
Published: May 2019

AbstractThree‐dimensional (3D) documenting and rubbing of rock art is aimed to produce descriptive and analytic graphic documentation with metric scale and geospatial information for archaeological analysis. Although the integrated surveying technologies of aerial photogrammetry, close‐range photogrammetry, and laser scanning have been widely used to generate the 3D models of archaeological sites, the implementation of these technologies in complex surroundings with steep terrain, such as riverside cliffs, remains challenging. In this study, we present an unmanned aerial vehicle (UAV)‐based structure‐from‐motion (SfM) photogrammetry approach to obtain the 3D geospatial data of rock paintings. A field data collection approach for high‐resolution multiperspective images using UAV equipped with a high‐resolution camera is implemented together with high accuracy ground control points (GCPs). An appropriate flowchart of multi‐view stereo (MVS) photogrammetry processing is designed including multi‐view dense matching, bundle adjustment (BA) and metric rectification for the orthoimages production of the rock paintings. A digital rubbing approach based on the orthoimages is proposed to obtain the geometry contents, including symbols and characters, of the rock paintings. The Huashan rock paintings, which are located on the vertical faces of the cliffs that line the course of Zuo River, is taken as a case study. Our proposed approach can obtain orthoimages of the Huashan rock paintings with 2 mm resolution. The reality‐based 3D model can reach the absolute accuracy of 5 mm. Clear, exact, and blur‐free metric rubbing images of the Huashan rock paintings are produced, which are useful for the research and preservation of Zhuang culture.
Probing Reaction Mechanism of [1,5]‐Migration in Pyrrolium and Pyrrole Derivatives: Activation of a Stronger Bond in Electropositive Groups Becomes Easier
Authors: Xie Qiong , Zhao Yu , Chen Dandan , Zhu Jun 
Published: May 2019

AbstractThe [1,5]‐migration reaction has attracted considerable attention from experimentalists and theoreticians for decades. Although it has been extensively investigated in various systems, studies on pyrrolium derivatives are underdeveloped. Herein, a theoretical study on the reaction mechanism of [1,5]‐migration in both pyrrolium and pyrrole derivatives is presented. The results reveal lower activation barriers in [1,5]‐migration of electropositive groups (AuPMe3 and SnH3) in pyrrolium derivatives, although the bond dissociation energies of the Au−N bond (98.8 kcal mol−1) and Sn−N bond (81.7 kcal mol−1) are larger than that of the N−F bond (57.6 kcal mol−1). The unexpectedly lower activation barriers (4.5 and 4.9 kcal mol−1 for AuPMe3 and SnH3, respectively) for [1,5]‐migration of electropositive groups, in comparison with the [1,5]‐fluorine shift, can be attributed to aromaticity stabilizing the transition states, as revealed by significantly negative nucleus‐independent chemical shift (NICS) values. Further studies indicate that charge distribution and frontier molecular orbitals also play some roles in [1,5]‐migration of pyrrolium derivatives.
Supramolecular Light‐Harvesting Antennas of Metal‐Coordinated Bis(8‐Hydroxyquinoline)‐Substituted Porphyrin Networks
Authors: Fujimoto Junko , Hayashi Sari , Kainuma Hideyuki , Manseki Kazuhiro , Udagawa Taro , Miyaji Hidekazu 
Published: May 2019

AbstractArtificial antenna complexes of metal‐coordinated bis(8‐hydroxyquinoline)‐substituted porphyrin networks that mimic antenna chromophores in plants were organized on titanium dioxide electrodes in photoelectrochemical cells. The generated photocurrents can be optimized according to the two ways of porphyrin self‐assembly due to the “antenna effect”: changing the number of assembled porphyrin monolayers and the number of generations of the metal‐coordinated porphyrin networks.
Pd‐Colloids‐Catalyzed/Ag2O‐Oxidized General and Selective Esterification of Benzylic Alcohols
Authors: Sable Vaibhav , Shah Jagrut , Sharma Anuja , Kapdi Anant R. 
Published: May 2019

AbstractPalladium colloids obtained from the degradation of Hermann–Beller palladacycle proved to be an efficient catalytic system in combination with silver oxide as a selective oxidant for the oxidative esterification of differently substituted benzyl alcohols in MeOH as solvent. Excellent reactivity exhibited by the catalytic system also allowed the alcoholic coupling partner to be changed from MeOH to a wide range of alcohols having diverse functionalities. The mildness of the developed protocol also made it possible to employ propargyl alcohol as the coupling partner without any observation of any interference of the terminal alkyne. Selective oxidative coupling of a primary alcoholic functional group over secondary in the case of glycols and glycerols was also made possible using the developed catalyst system. To test the relevancy of Pd/Ag combined catalysis mixed Pd/Ag colloids were synthesized, characterized by TEM, XRD and XPS and applied to oxidative‐esterification successfully.
Composite active disturbance rejection robust control for a prototype of an active damping artificial ankle prosthesis
Authors: Serrano Hugo Luis , Chairez Isaac , Luviano‐Juárez Alberto 
Published: May 2019

AbstractThe problem of robust control applied to adjust the configuration of an ankle prosthesis based on disturbance estimation has been addressed in this study. Active disturbance rejection control was the paradigm used for controlling the robotic prosthesis by means of a direct active estimation. Based on this active estimation, the robust controller implemented the disturbance cancellation providing a fast converge to the origin of the tracking error. The uncertainties affecting the prosthesis dynamics were identified by a high‐order extended state high gain observer. This identification was used to force the tracking between the actual position and force needed in the ankle prosthesis and some reference values obtained by a biomechanical gait cycle analysis. Therefore, the estimated states were used to implement a robust output feedback controller that was effective to reject actively the perturbations. This rejection implemented within the controller forced the trajectory tracking to a small vicinity of the origin. A strategy based on composite Lyapunov function served to prove that tracking problem for the prosthesis was successfully solved despite the switching nature of the gait cycle. The controller was implemented in numerical simulations for showing the convergence of the tracking error. The convergence of this tracking error to the region around the origin was obtained within the first second of simulation.
Associations between mindfulness and general change mechanisms in individual therapy: Secondary results of a randomised controlled trial
Authors: D’Errico Louisa , Call Manuela , Blanck Paul , Vonderlin Eva , Bents Hinrich , Mander Johannes 
Published: May 2019

AbstractObjectiveThe aim of this study was to investigate the possible effects of the interactions between mindfulness‐based session introductions and general change mechanisms on outcome in cognitive behavioural therapy (CBT).MethodWe investigated the effects of different session introductions on change mechanisms and their prediction of clinical outcome over the course of 25 sessions of training therapy. We compared session introductions with mindfulness (M) elements with progressive muscle relaxation (PMR) and treatment as usual (TAU) in routine CBT sessions conducted by therapists in training. Participants included 162 patients who were diagnosed primarily with either depression or anxiety disorder and 48 therapists. To address the nested data structure, we used multilevel models.ResultsMultilevel modelling (MLM) indicated that the interaction between an increase in several general change mechanisms and treatment condition (TAU + M vs. TAU + PMR) on therapeutic outcome was significant. From the patient perspective, MLM indicated that only the interaction between an increase in one general change mechanism (clarification of meaning) and treatment condition (TAU + M vs. TAU + PMR) turned out significantly. From both perspectives, correlation analyses revealed that general change mechanism effects on outcome were stronger in TAU + M than in TAU + PMR.ConclusionMindfulness has an impact on general change mechanisms, especially for therapists. These associations lead to a significantly higher effect on outcome compared to introductions with PMR.
Technologies for the Storage of Hydrogen. Part 2: Irreversible Conversion and Comparison
Authors: Müller Karsten 
Published: May 2019

AbstractGenerally, hydrogen storage is the storage of a chemical substance. Yet, it is also often proposed and discussed as a form of energy storage. Since many technologies for the storage of hydrogen involve a chemical conversion anyway, it is reasonable to consider skipping the backwards conversion to release hydrogen again. If hydrogen is converted, e.g., by a chemical reaction into a hydrocarbon, it is reasonable to directly combust this hydrocarbon. Such approaches open new routes for the utilization of hydrogen energy. The applied technologies are introduced and a comparison of storage options with recovery of elemental hydrogen is presented.