bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hohe Block‐Temperatur der Magnetisierung und herausragende Koerzitivfeldstärke im Azafulleren Tb2@C79N mit einer Einelektronen‐Terbium‐Terbium‐Bindung
Authors: Velkos Georgios , Krylov Denis S. , Kirkpatrick Kyle , Spree Lukas , Dubrovin Vasilii , Büchner Bernd , Avdoshenko Stanislav M. , Bezmelnitsyn Valeriy , Davis Sean , Faust Paul , Duchamp James , Dorn Harry C. , Popov Alexey A. 
Published: February 2019

AbstractDas Azafulleren Tb2@C79N wird als Einzelmolekülmagnet mit einer hohen 100‐s‐Block‐Temperatur der Magnetisierung von 24 K und hoher Koerzitivfeldstärke identifiziert. Die magnetischen Momente von Tb mit magnetischer Vorzugsachsen‐Anisotropie sind durch den ungepaarten Spin der Einelektronenbindung stark gekoppelt. Die Relaxation der Magnetisierung findet in Tb2@C79N bei Temperaturen unter 15 K durch Quantentunneln der Magnetisierung mit einer charakteristischen Relaxationszeit von τQTM=16 462±1230 s statt. Bei höheren Temperaturen folgt die Relaxation dem Orbach‐Mechanismus mit einer Barriere von 757±4 K, was dem angeregten Zustand entspricht, in dem einer der Tb‐Spins umgekehrt wird.
Generation of Nanoparticle, Atomic‐Cluster, and Single‐Atom Cobalt Catalysts from Zeolitic Imidazole Frameworks by Spatial Isolation and Their Use in Zinc–Air Batteries
Authors: Han Xiaopeng , Ling Xiaofei , Wang Ying , Ma Tianyi , Zhong Cheng , Hu Wenbin , Deng Yida 
Published: February 2019

AbstractThe size effect of transition‐metal nanoparticles on electrocatalytic performance remains ambiguous especially when decreasing the size to the atomic level. Herein, we report the spatial isolation of cobalt species on the atomic scale, which was achieved by tuning the zinc dopant content in predesigned bimetallic Zn/Co zeolitic imidazole frameworks (ZnCo‐ZIFs), and led to the synthesis of nanoparticles, atomic clusters, and single atoms of Co catalysts on N‐doped porous carbon. This synthetic strategy allowed an investigation of the size effect on electrochemical behavior from nanometer to Ångström dimensions. Single‐atom Co catalysts showed superior bifunctional ORR/OER activity, durability, and reversibility in Zn–air batteries compared with the other derivatives and noble‐metal Pt/C+RuO2, which was attributed to the high reactivity and stability of isolated single Co atoms. Our findings open up a new avenue to regulate the metal particle size and catalytic performance of MOF derivatives.
Nucleophilic Aromatic Substitution at Benzene with Powerful Strontium Hydride and Alkyl Complexes
Authors: Rösch Bastian , Gentner Thomas Xaver , Elsen Holger , Fischer Christian A. , Langer Jens , Wiesinger Michael , Harder Sjoerd 
Published: February 2019

AbstractKey to the isolation of the first alkyl strontium complex was the synthesis of a strontium hydride complex that is stable towards ligand exchange reactions. This goal was achieved by using the super bulky β‐diketiminate ligand DIPePBDI (CH[C(Me)N‐DIPeP]2, DIPeP=2,6‐diisopentylphenyl). Reaction of DIPePBDI‐H with Sr[N(SiMe3)2]2 gave (DIPePBDI)SrN(SiMe3)2, which was converted with PhSiH3 into [(DIPePBDI)SrH]2. Dissolved in C6D6, the strontium hydride complex is stable up to 70 °C. At 60 °C, H–D isotope exchange gave full conversion into [(DIPePBDI)SrD]2 and C6D5H. Since H–D exchange with D2 is facile, the strontium hydride complex served as a catalyst for the deuteration of C6H6 by D2. Reaction of [(DIPePBDI)SrH]2 with ethylene gave [(DIPePBDI)SrEt]2. The high reactivity of this alkyl strontium complex is demonstrated by facile ethylene polymerization and nucleophilic aromatic substitution with C6D6, giving alkylated aromatic products and [(DIPePBDI)SrD]2.
Selective and Efficient Removal of Fluoride from Water: In Situ Engineered Amyloid Fibril/ZrO2 Hybrid Membranes
Authors: Zhang Qingrui , Bolisetty Sreenath , Cao Yiping , Handschin Stephan , Adamcik Jozef , Peng Qiuming , Mezzenga Raffaele 
Published: February 2019

AbstractWe report a new strategy for efficient removal of F− from contaminated water streams, and it relies on carbon hybrid membranes made of amyloid fibril/ZrO2 nanoparticles (<10 nm). These membranes exhibit superior selectivity for F− against various competitive ions, with a distribution coefficient (Kd) as high as 6820 mL g−1, exceeding commercial ion‐exchange resins (IRA‐900) by 180 times and outdoing the performance of most commercial carbon‐activated aluminum membranes. At both low and high (ca. 200 mg L−1) F− concentrations, the membrane efficiency exceeds 99.5 % removal. For real untreated municipal tap water (ca. 2.8 mg L−1) under continuous operating mode, data indicates that about 1750 kg water m−2 membrane can be treated while maintaining drinking water quality, and the saturated membranes can be regenerated and reused several times without decrease in performance. This technology is promising for mitigating the problem of fluoride water contamination worldwide.
Selectivity Switch in a Rhodium(II) Carbene Triggered Cyclopentannulation: Divergent Access to Three Polycyclic Indolines
Authors: Liu Hua‐Kui , Wang Sunewang R. , Song Xiang‐Yang , Zhao Liu‐Peng , Wang Lijia , Tang Yong 
Published: February 2019

AbstractA selectivity switch in a RhII/carbene‐triggered cyclopentannulation with catalytic InCl3 is reported for the first time, affording both diastereomers of the fused spiroindolines and an unusual bridged tetracyclic indoline in high yields with excellent selectivities. Mechanistic studies indicate an intramolecular annulation of the indole with an in situ formed aminocyclopropane. The stepwise thermal conversions from the kinetic spiroindoline to the metastable bridged indoline, and then to the thermodynamic spiroindoline, involving a ring‐opening rearrangement of a cyclopentane, is crucial for selectivity control.
High Blocking Temperature of Magnetization and Giant Coercivity in the Azafullerene Tb2@C79N with a Single‐Electron Terbium–Terbium Bond
Authors: Velkos Georgios , Krylov Denis S. , Kirkpatrick Kyle , Spree Lukas , Dubrovin Vasilii , Büchner Bernd , Avdoshenko Stanislav M. , Bezmelnitsyn Valeriy , Davis Sean , Faust Paul , Duchamp James , Dorn Harry C. , Popov Alexey A. 
Published: February 2019

AbstractThe azafullerene Tb2@C79N is found to be a single‐molecule magnet with a high 100‐s blocking temperature of magnetization of 24 K and large coercivity. Tb magnetic moments with an easy‐axis single‐ion magnetic anisotropy are strongly coupled by the unpaired spin of the single‐electron Tb−Tb bond. Relaxation of magnetization in Tb2@C79N below 15 K proceeds via quantum tunneling of magnetization with the characteristic time τQTM=16 462±1230 s. At higher temperature, relaxation follows the Orbach mechanism with a barrier of 757±4 K, corresponding to the excited states, in which one of the Tb spins is flipped.
Hybrid Organic–Inorganic Thermoelectric Materials and Devices
Authors: Jin Huile , Li Jun , Iocozzia James , Zeng Xin , Wei Pai‐Chun , Yang Chao , Li Nan , Liu Zhaoping , He Jr Hau , Zhu Tiejun , Wang Jichang , Lin Zhiqun , Wang Shun 
Published: February 2019

AbstractHybrid organic–inorganic materials have been considered as a new candidate in the field of thermoelectric materials since the last decade owing to their great potential to enhance the thermoelectric performance by utilizing the low thermal conductivity of organic materials and the high Seebeck coefficient, and high electrical conductivity of inorganic materials. Herein, we provide an overview of interfacial engineering in the synthesis of various organic–inorganic thermoelectric hybrid materials, along with the dimensional design for tuning their thermoelectric properties. Interfacial effects are examined in terms of nanostructures, physical properties, and chemical doping between the inorganic and organic components. Several key factors which dictate the thermoelectric efficiency and performance of various electronic devices are also discussed, such as the thermal conductivity, electric transportation, electronic band structures, and band convergence of the hybrid materials.
Improvements in thermal conductivity and mechanical properties of HDPE/nano‐SiC composites by the synergetic effect of extensional deformation and ISBS
Authors: Xiaochun Yin , Yang Li , Di Cheng , Yanhong Feng , Guangjian He 
Published: February 2019

ABSTRACTA new melt blending method under synergy of extensional deformation and in‐situ bubble stretching for high‐density polyethylene (HDPE) thermally conductive composites filled by nano silicon carbide (nano‐SiC) was reported. Effects of loadings and mixing time of azodicarbonamide (AC) foaming agent on the properties of the composites were experimentally studied. Scanning electron microscopy imaging showed that the nano‐SiC particles dispersed uniformly in the HDPE matrix with the addition of AC. The complex viscosity and storage modulus increased with increasing AC content and decreased with increasing mixing time. The mechanical properties of the composites improved with the addition of AC and proper mixing times. The thermal conductivity of the composites increased from 0.2 to 0.7 W m−1 K−1 without any damage to the mechanical properties when the mixing time increased from 2 to 6 min. These results showed that the new mixing technique enables us to prepare particle‐filled thermally conductive polymer composites. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47648.
Novel dye for detection of callus embryo by confocal laser scanning fluorescence microscopy
Authors: Kirilova Elena , Mickevica Ilona , Mezaraupe Ligita , Puckins Aleksandrs , Rubenina Ilze , Osipovs Sergejs , Kokina Inese , Bulanovs Andrejs , Kirjusina Muza , Gavarane Inese 
Published: February 2019

AbstractIn the present study a new luminescent dye 3‐N‐(2‐pyrrolidinylacetamido)benzanthrone (AZR) was synthesized. Spectroscopic measurements of the novel benzanthrone 3‐aminoderivative were performed in seven organic solvents showing strong fluorescence. The capability of the prepared dye for visualization has been tested on flax, red clover and alfalfa to determinate the embryo in plant callus tissue cultures. Callus cells were stained with AZR and further analysed utilizing confocal laser scanning fluorescence microscopy. Performed experiments show high visualization effectiveness of newly synthesized fluorescent dye AZR that is efficient in fast and relatively inexpensive diagnostics of callus embryos that are problematic due to in vitro culture specificity.
Utility of bevacizumab in advanced hepatocellular carcinoma: A veterans affairs experience
Authors: Wattenberg Max M. , Damjanov Nevena , Kaplan David E. 
Published: February 2019

AbstractHepatocellular carcinoma (HCC) is a challenging to treat malignancy with few available systemic therapies. Angiogenesis has been implicated in the pathogenesis of HCC and prior studies have suggested a role for anti‐VEGF therapy. Prior to FDA approval of second‐line therapy for advanced HCC, from 2008 until 2017, we initiated bevacizumab monotherapy (5‐10 mg/kg every 2‐3 weeks) in 12 patients with intolerance of or progression during sorafenib therapy. Bevacizumab therapy was well tolerated with only 1/12 patients experiencing a grade 3‐4 treatment‐related adverse event (transient ischemic attack) and only 2/12 patients discontinued the therapy due to adverse events. Median overall survival was 20.2 months (IQR, 7.0‐43.5), with a median time to radiologic progression of 10.4 months (IQR, 2.8‐16.1) and a disease control rate of 54%. Taken together, our experience provides rationale for further prospective investigation of bevacizumab for the treatment of advanced HCC.
A role of GCC88 in the retrograde transport of CI‐M6PR and the maintenance of lysosomal activity
Authors: Cui Yi , Yang Zhe , Teasdale Rohan D. 
Published: February 2019

AbstractGCC88 is a golgin coiled‐coil protein at the trans‐Golgi (TGN) that functions as a tethering factor for the endosome‐derived retrograde transport vesicles. Here, we demonstrate that GCC88 is required for the endosome‐to‐TGN retrograde transport of the cation‐independent mannose 6‐phosphate receptor (CI‐M6PR). The knockout of GCC88 perturbs the retrieval of CI‐M6PR and decreases its cellular level at the steady state, which causes the improper processing of newly synthesized cathepsin‐D, a lysosomal hydrolase dependent on CI‐M6PR for its delivery to lysosomes. At the whole cell level, the knockout of GCC88 reduces the lysosomal proteolytic capacity but does not impair of the efficiency of autophagy within these cells.
Classification scheme for ductal morphology in cyanotic patients with ductal dependent pulmonary blood flow and association with outcomes of patent ductus arteriosus stenting
Authors: Qureshi Athar M. , Goldstein Bryan H. , Glatz Andrew C. , Agrawal Hitesh , Aggarwal Varun , Ligon R. Allen , McCracken Courtney , McDonnell Alicia , Buckey Timothy M. , Whiteside Wendy , Metcalf Christina M. , Petit Christopher J. 
Published: February 2019

AbstractObjectivesTo devise a classification scheme for ductal morphology in patients with ductal dependent pulmonary blood flow (PBF) that can be used to assess outcomes.BackgroundThe impact of ductal morphology on outcomes following patent ductus arteriosus (PDA) stenting is not well defined.MethodsPatients <1 year of age who underwent PDA stenting for ductal dependent PBF at the four centers comprising the Congenital Catheterization Research Collaborative (CCRC) were included. A classification scheme for PDA morphology was devised based on a tortuosity index (TI)—Type I (straight), Type II (one turn), and Type III (multiple turns). A subtype classification was used based upon the ductal origin.ResultsOne hundred and five patients underwent PDA stenting. TI was Type I in 58, Type II in 24, and Type III in 23 PDAs, respectively. There was a significant association between ductal origin and vascular access site (p < 0.001). Procedure times and need for >1 stent did not differ based on TI. Greater TI was associated with pulmonary artery (PA) jailing (p = 0.003). Twelve (11.4%) patients underwent unplanned reintervention, more commonly with greater TI (p = 0.022) and PA jailing (p < 0.001). At the time of subsequent surgical repair/palliative staging, PA arterioplasty was performed in 32 patients, more commonly when a PA was jailed (p = 0.048). PA jailing did not affect PA size at follow up.ConclusionsThe proposed qualitative and quantitative PDA morphology classification scheme may be helpful in anticipating outcomes in patients with ductal dependent PBF undergoing PDA stenting.
Trends in complete heart block after transcatheter aortic valve replacement: A population based analysis
Authors: Al‐Ogaili Ahmed , Fugar Setri , Okoh Alexis , Kolkailah Ahmed A. , Al Hashemi Nawaf , Ayoub Ali , Russo Mark J. , Kavinsky Clifford J. 
Published: February 2019

AbstractObjectivesTo define the national rate of complete heart block (CHB) after transcatheter aortic valve replacement (TAVR) and its impact on procedural mortality, overall cost, and length of hospital stay.BackgroundCHB leading to permanent pacemaker (PPM) implantation is one of the most common complications post TAVR. National data on the temporal trend of CHB post TAVR are lacking.MethodsWe queried the 2012–2014 National Inpatient Sample databases to identify all patients who underwent TAVR. Patients with preoperative pacemakers or implantable cardioverter‐defibrillators were excluded. Association between CHB and outcomes, and overall trends in rate of CHB, PPM implantation, and inpatient mortality were examined.ResultsOf 35,500 TAVR procedures, 3,675 (10.4%) had CHB. Overall, occurrence of CHB significantly increased from 8.4% in 2012 to 11.8% in 2014 (adjusted OR per year: 1.23; 95% confidence interval [CI]: 1.17–1.29, P trend <0.001). During the same period, PPM implantation increased from 9.5 to 13.7% (adjusted OR per year: 1.22; 95% CI: 1.16–1.28, P trend <0.001). Patients with CHB had higher odds of in‐hospital mortality when compared to patients without CHB (5.9% vs. 4.2%, adjusted OR: 1.32; 95% CI: 1.12–1.56; p = 0.001). Moreover, CHB was also associated with longer length of stay (LOS) and higher hospitalization cost.ConclusionsThere was a significant increase in rates of CHB and PPM implantation over the study period. Development of CHB was associated with increased in‐hospital mortality, LOS, and hospitalization cost.
Catalytic Dehydrogenation of Formic Acid with Ruthenium‐PNP‐Pincer Complexes: Comparing N‐Methylated and NH‐Ligands
Authors: Agapova Anastasiya , Alberico Elisabetta , Kammer Anja , Junge Henrik , Beller Matthias 
Published: February 2019

AbstractComplexes Ru(H)(Cl)(CO)(HN{CH2CH2P(iPr)2}2) 7 and Ru(H)(Cl)(CO)(CH3N{CH2CH2P(iPr)2}2) 8 were compared for the selective dehydrogenation (DH) of formic acid (FA) at different pH values. Remarkably, highest activities were observed in acidic environment (pH 4.5). Under all investigated conditions, the N‐methylated complex 8 showed improved performance compared to 7. These observations can be mechanistically explained with protonation of 4H/3Me being the key step in formic acid DH for both complexes.
Interplay Between Site Activity and Density of BCC Iron for Ammonia Synthesis Based on First‐Principles Theory
Authors: Zhang Bing‐Yan , Su Hai‐Yan , Liu Jin‐Xun , Li Wei‐Xue 
Published: February 2019

AbstractSite activity and density are two key factors in determining the overall activity of catalysts in heterogeneous catalysis. Combined DFT calculation, Wulff construction and micro‐kinetic analysis, we reveal here a significant interplay between site activity and density of bcc iron catalyzed ammonia synthesis at low coverage regime. It is found that for large size particles, Fe (111) and (311) surfaces that consist of active C7 sites are limited by their low site density, whereas those with the most abundant sites are limited by their low activity. In contrast, Fe (221), (211) and (310) surfaces which consist of active C7 and/or B5 sites and remain abundant, dominate the overall reaction rate, turn‐over‐frequency and mass specific activity. Turn‐over‐frequency of the smaller Fe particles (2–6 nm) decreases by a factor of two or three due to the absence of (221) surface. For the particle size less than 2 nm, the corresponding activity decreases dramatically owing to the absence of all active C7 and/or B5 sites. Interplay of site abundance and intrinsic activity of catalysts is highlighted, and the insights revealed could be used to design and develop better catalysts for ammonia synthesis and other important reactions of technological interest.
Light‐Responsive Arylazopyrazole Gelators: From Organic to Aqueous Media and from Supramolecular to Dynamic Covalent Chemistry
Authors: Chu Chih‐Wei , Stricker Lucas , Kirse Thomas M. , Hayduk Matthias , Ravoo Bart Jan 
Published: February 2019

AbstractVersatile photoresponsive gels based on tripodal low molecular weight gelators (LMWGs) are reported. A cyclohexane‐1,3,5‐tricarboxamide (CTA) core provides face‐to‐face hydrogen bonding and a planar conformation, inducing the self‐assembly of supramolecular polymers. The CTA core was substituted with three arylazopyrazole (AAP) arms. AAP is a molecular photoswitch that isomerizes reversibly under alternating UV and green light irradiation. The E isomer of AAP is planar, favoring the self‐assembly, whereas the Z isomer has a twisted structure, leading to a disassembly of the supramolecular polymers. By using tailor‐made molecular design of the tripodal gelator, light‐responsive organogels and hydrogels were obtained. Additionally, in the case of the hydrogels, AAP was coupled to the core through hydrazones, so that the hydrogelator and, hence, the photoresponsive hydrogel could also be assembled and disassembled by using dynamic covalent chemistry.
Diverse Role of Solvents in Controlling Supramolecular Chirality
Authors: Xue Shixin , Xing Pengyao , Zhang Jingbo , Zeng Yongfei , Zhao Yanli 
Published: February 2019

AbstractSupramolecular self‐assembly stands for the spontaneous aggregation of small organic compounds or polymers into ordered structures at any scale. When being induced by inherent molecular chiral centers or ambient asymmetric factors, asymmetric spatial arrangement between building units shall occur, which is defined as supramolecular chirality. Except for molecular design, utilizing external stimulus factors to tune supramolecular chirality is a promising approach. In this Concept article, we particularly discuss the important role of solvents in manipulating the chirality of self‐assembled systems. The impact of solvents on the chirality is generally based on three properties of solvents, i.e., chirality, polarity, and active coassembly with building blocks. Molecular self‐assembly in chiral solvents could undergo the chirality transfer, exhibiting a chiral induction effect. Solvent polarity often determines intermolecular orientation. As a consequence, those building blocks with both polar and apolar segments might change their chirality depending on the solvent polarity. We elaborate the active participation of solvent molecules into ordered structures together with building blocks, where solvents and building blocks exhibit a coassembly manner. By specific treatments such as heating and cooling, solvents could be released or re‐entrapped, allowing a smart control over supramolecular chirality. The solvent effect in manipulating two‐dimensional chiral self‐assemblies is then discussed. The perspective and future development in this research field are presented at last.
Introducing the Chiral Transient Directing Group Strategy to Rhodium(III)‐Catalyzed Asymmetric C−H Activation
Authors: Li Guozhu , Jiang Jijun , Xie Hui , Wang Jun 
Published: February 2019

AbstractThe chiral transient directing group (TDG) strategy has been successfully introduced to the rhodium(III)‐catalyzed asymmetric C−H activation. In the presence of a catalytic amount of a chiral amine and an achiral rhodium catalyst, various chiral phthalides were synthesized from simple aldehydes with high chemoselectivity, regioselectivity, and enantioselectivity (53 examples, up to 73 % yield and >99 % ee). It is noteworthy that the chiral induction model is different from the previously reported chiral TDG system using amino acid derivatives and palladium salts. The imino group generated in situ from chiral amine and aldehyde acts as the monodentate TDG to promote the C−H activation, stereoselectively generating the chiral rhodacycle bearing a chiral metal center. Moreover, the stereogenic center of the product is created and stereocontrolled during the Grignard‐type addition of the C−Rh bond to aldehyde, rather than during the C−H activation step.