bluuebunny/crossref_metadata_2025_split huggingface dataset:
Robust Microporous Metal–Organic Frameworks for Highly Efficient and Simultaneous Removal of Propyne and Propadiene from Propylene
Authors: Peng Yun‐Lei , He Chaohui , Pham Tony , Wang Ting , Li Pengfei , Krishna Rajamani , Forrest Katherine A. , Hogan Adam , Suepaul Shanelle , Space Brian , Fang Ming , Chen Yao , Zaworotko Michael J. , Li Jinping , Li Libo , Zhang Zhenjie , Cheng Peng , Chen Banglin 
Published: May 2019

AbstractSimultaneous removal of trace amounts of propyne and propadiene from propylene is an important but challenging industrial process. We report herein a class of microporous metal–organic frameworks (NKMOF‐1‐M) with exceptional water stability and remarkably high uptakes for both propyne and propadiene at low pressures. NKMOF‐1‐M separated a ternary propyne/propadiene/propylene (0.5 : 0.5 : 99.0) mixture with the highest reported selectivity for the production of polymer‐grade propylene (99.996 %) at ambient temperature, as attributed to its strong binding affinity for propyne and propadiene over propylene. Moreover, we were able to visualize propyne and propadiene molecules in the single‐crystal structure of NKMOF‐1‐M through a convenient approach under ambient conditions, which helped to precisely understand the binding sites and affinity for propyne and propadiene. These results provide important guidance on using ultramicroporous MOFs as physisorbent materials.
Synthesis, structural characterization and DNA binding affinity of new bioactive nano‐sized transition metal complexes with sulfathiazole azo dye for therapeutic applications
Authors: Saad Fawaz A. , El‐Ghamry Hoda A. , Kassem Mohammed A. 
Published: May 2019

The azo dye ligand 4‐(5‐chloro‐2‐hydroxyphenylazo)‐N‐thiazol‐2‐ylbenzenesulfonamide (H2L) formed by the coupling reaction of sulfathiazole and p‐chlorophenol was synthesized and characterized using elemental analysis and Fourier transform infrared (FT‐IR) as well as UV–visible spectra. Nano‐sized divalent Cu, Co, Ni, Mn and Zn complexes of the synthesized azo dye ligand were prepared and investigated using various spectroscopic and analytical techniques. Elemental and thermal analyses indicated the formation of the Cu(II), Ni(II) and Mn(II) complexes in a molar ratio of 1:2 (L:M) while Co(II) and Zn(II) complexes exhibited a 1:1 (M:L) ratio. FT‐IR spectral studies confirmed the coordination of the ligand to the metal ions through the phenolic hydroxyl oxygen, azo nitrogen, sulfonamide oxygen and/or thiazole nitrogen. The geometric arrangements around the central metal ions were investigated applying UV–visible and electron spin resonance spectra, thermogravimetric analysis and molar conductance measurements. X‐ray diffraction patterns revealed crystalline nature of H2L and amorphous nature of all synthesized complexes. Transmission electron microscopy images confirmed nano‐sized particles and their homogeneous distribution over the complex surface. Antibacterial, antifungal and antitumour activities of the investigated complexes were screened compared with familiar standard drugs to confirm their potential therapeutic applications. The Cu(II) complex showed IC50 of 3.47 μg ml−1 (5.53 μM) against hepatocellular carcinoma cells, which means that it is a more potent anticancer drug compared with the standard cisplatin (IC50 = 3.67 μg ml−1 (12.23 μM)). Furthermore, the Co(II), Ni(II), Cu(II) and Zn(II) complexes displayed IC50 greater than that of an applied standard anticancer agent (5‐flurouracil) towards breast carcinoma cells. Hence, these complexes can be considered as promising anticancer drugs. The mode of binding of the complexes with salmon serum DNA was determined through electronic absorption titration and viscosity studies.
Influence of expandable graphite on flame retardancy and thermal stability property of unsaturated polyester resins/organic magnesium hydroxide composites
Authors: He Jinnan , Zeng Wei , Shi Miaomiao , Lv Xinyao , Fan Hui , Lei Ziqiang 
Published: May 2019

ABSTRACTAn eco‐friendly flame retardant unsaturated polyester resin (UPR) material was prepared by combination organic magnesium hydroxide (OMH) and expandable graphite (EG). Different from direct addition of magnesium hydroxide (MH) in UPR matrix‐like traditional method, OMH as a reactive monomer participates in the polycondensation reaction of UPR was more effective in improving the compatibility of flame retardant with matrix. Interestingly, the flame retardant UPR composites exhibited a more satisfactory flame retardant effect when a certain amount of 8 wt % EG was added into UPR/OMH matrix because of the synergistic effect between OMH and EG, resulted in the limited oxygen index from 21.7 to 28.5% and UL‐94 test passed V‐0 rating. Moreover, the peak heat release rate, total heat release, and smoke production rate of flame retardant UPR composites significantly reduced. The excellent flame retardancy was due to the formation of a dense and continuous carbon layer in the later stages of combustion. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 47881.
Integrated and secure web‐based examination management system
Authors: Al‐Hawari Feras , Alshawabkeh Mai , Althawbih Haytham , Abu Nawas Omar 
Published: May 2019

AbstractA web‐based examination management system that is implemented in‐house is discussed in this paper. It is designed based on the Java enterprise edition three‐tier architecture. It also allows defining and setting up exams according to a flexible tree‐based exams structure. Moreover, it integrates a rich text editor for composing exams suitable for different engineering and language disciplines. In addition, it automates the scheduling, grading, and reporting processes to relieve instructors from such cumbersome tasks. Furthermore, its capabilities and integration with different databases enable it to offer several security schemes that support strong multifactor authentication and authorization, detect impersonation, and prevent cheating. Besides, it provides an easy to use and informative wizard that enables students to take exams. Not to mention, the deployment results illustrate that the system has been successfully used to organize online exams in several semesters over the past 3 academic years. Finally, the conducted user surveys responses assert that the system is also user‐friendly, cutting edge, capable, reliable, fast, and highly available.
Getting absorbed in group therapy: Absorption and cohesion in integrative group treatment
Authors: Kealy David , McCloskey Katharine D. , Cox Daniel W. , Ogrodniczuk John S. , Joyce Anthony S. 
Published: May 2019

AbstractBackgroundAbsorption is a trait‐like dimension reflecting a tendency to immerse oneself in sensory and imaginative experiences. This characteristic has scarcely been investigated in group psychotherapy. The present study examined absorption in relation to clients′ experience of early group process, and as a moderator of group cohesion and improvement in psychiatric symptoms, in an integrative group treatment programme.MethodsParticipants included 81 clients, who completed an 18‐week programme of intensive, integrative, group treatment for personality dysfunction. Clients completed assessments of absorption and psychiatric symptom severity, and rated three aspects of group cohesion at week 5 of the programme.ResultsAbsorption was significantly associated with stimulation from the group after controlling for severity of symptoms and personality dysfunction. Moderation analyses found a significant interaction effect for absorption and the stimulation component of group cohesion with regard to symptom improvement. Absorption thus had a moderating effect on the relationship between stimulation from the group and improvement in psychiatric symptoms; for clients with higher levels of absorption, stimulation from group therapy contributed significantly to reduced symptom severity at post‐treatment.DiscussionFindings suggest that absorption may be a salient personality feature to consider in group therapy for clients with personality dysfunction.ConclusionAbsorption may contribute to treatment outcome, in that clients′ absorption tendencies could interact with their enthusiasm for the group experience, thereby leading to reduced symptoms following intensive group treatment.
Exploring the Functional Consequences of Protein Backbone Alteration in Ubiquitin through Native Chemical Ligation
Authors: Werner Halina M. , Estabrooks Samuel K. , Preston G. Michael , Brodsky Jeffrey L. , Horne W. Seth 
Published: May 2019

AbstractUbiquitin (Ub) plays critical roles in myriad protein degradation and signaling networks in the cell. We report herein Ub mimetics based on backbones that blend natural and artificial amino acid units. The variants were prepared by a modular route based on native chemical ligation. Biological assays show that some are enzymatically polymerized onto protein substrates, and that the resulting Ub tags are recognized for downstream pathways. These results advance the size and complexity of folded proteins mimicked by artificial backbones and expand the functional scope of such agents.
Functional Characterization of 3‐Aminobenzoic Acid Adenylation Enzyme PctU and UDP‐N‐Acetyl‐d‐Glucosamine: 3‐Aminobenzoyl‐ACP Glycosyltransferase PctL in Pactamycin Biosynthesis
Authors: Kudo Fumitaka , Zhang Jiahao , Sato Shusuke , Hirayama Akane , Eguchi Tadashi 
Published: May 2019

AbstractPactamycin is an antibiotic produced by Streptomyces pactum with antitumor and antimalarial properties. Pactamycin has a unique aminocyclitol core that is decorated with 3‐aminoacetophenone, 6‐methylsaliciate, and an N,N‐dimethylcarbamoyl group. Herein, we show that the adenylation enzyme PctU activates 3‐aminobenzoic acid (3ABA) with adenosine triphosphate and ligates it to the holo form of the discrete acyl carrier protein PctK to yield 3ABA‐PctK. Then, 3ABA‐PctK is N‐glycosylated with uridine diphosphate‐N‐acetyl‐d‐glucosamine (UDP‐GlcNAc) by the glycosyltransferase PctL to yield GlcNAc‐3ABA‐PctK. Because 3ABA is known to be a precursor of the 3‐aminoacetophenone moiety, PctU appears to be a gatekeeper that selects the appropriate 3‐aminobenzoate starter unit. Overall, we propose that acyl carrier protein‐bound glycosylated 3ABA derivatives are biosynthetic intermediates of pactamycin biosynthesis.
Further delineation of the phenotype caused by a novel large homozygous deletion of GRID2 gene in an adult patient
Authors: Taghdiri Maryam , Kashef Atie , Abbassi Golemaryam , Moshtagh Azadeh , Sadatian Neda , Fardaei Majid , Najafi Kimia , Kariminejad Roxana 
Published: May 2019

Key Clinical MessageDifferent mutations in glutamate receptor ionotropic delta 2 (GRID2) gene cause cerebellar ataxia in human. We report the largest homozygous deletion of the GRID2 gene reported to date, most probably causing complete loss of the gene product. Our patient presents mainly early onset cerebellar ataxia, cerebellar atrophy, nystagmus, and developmental delay with the least amount of intellectual disability.
Metal‐Organic‐Framework‐Derived Nitrogen‐Doped Hybrid Nickel‐Iron‐Sulfide Architectures on Carbon Cloth as Efficient Electrocatalysts for the Oxygen Evolution Reaction
Authors: Shen Yirui , Wang Ling , Jiang Pingping , Lee Wee Siang Vincent , Xue Junmin 
Published: May 2019

AbstractMetal‐organic framework (MOF)‐derived nitrogen‐doped NiFe‐sulfides/carbon hybrid architectures were successfully constructed on carbon cloth (CC) with different n(Ni)/n(Fe) ratios through a simultaneous carbonization and sulfurization procedure from the corresponding bimetal NiFe‐based MOFs. The samples were directly utilized as the working electrodes for the oxygen evolution reaction (OER). The optimal sample N‐NiFe‐S/C‐8/2@CC possessed superior OER electrocatalytic activity with a remarkably low overpotential of 232 mV at a current density of 10 mA cm−2 in 1 M KOH aqueous solution. At the same time, a small Tafel slope of 58 mV dec−1 was achieved and excellent durability was also demonstrated. Such superior OER activity and durability of N‐NiFe‐S/C@CC may originate from a synergetic effect between Fe and Ni, the nitrogen‐doped carbon matrix derived from MOFs, and the direct growth of active materials on CC. This facile approach of preparing bimetal sulfide compounds derived from MOFs may be a viable method for designing and preparing high‐performing electrocatalytic materials for wider applications.
Mechanochemically Assisted Synthesis of Ruthenium Clusters Embedded in Mesoporous Carbon for an Efficient Hydrogen Evolution Reaction
Authors: Liu Xiaofei , Jin Tian Leo , Hood Zachary D. , Tian Chengcheng , Guo Yanglong , Zhan Wangcheng 
Published: May 2019

AbstractRuthenium (Ru) clusters are reported as efficient electrocatalysts for the hydrogen evolution reaction (HER). However, a precise and facile synthetic protocol for preparing Ru clusters is still a challenge. Herein, a facile mechanochemically assisted strategy was proposed to synthesize ruthenium clusters embedded in mesoporous carbon (Ru‐CN/MC). Importantly, for the synthesis of Ru‐CN/MC, melamine was utilized not only as a capping agent to stabilize Ru clusters, but also to provide N sites for the carbon support. The well‐designed Ru‐CN/MC exhibits impressive HER performance in 1 M KOH, which shows an extremely low overpotential of 17 mV at a current density of 10 mA cm−2. More importantly, excellent long‐term electrochemical stability in both alkaline and acid electrolyte was achieved for Ru‐CN/MC. Therefore, the developed synthesis method for Ru clusters and the subsequent insightful investigations on the HER performance shed light on new opportunities for exploring highly efficient and renewable HER electrocatalysts.
Unraveling the Mechanisms of the Excited‐State Intermolecular Proton Transfer (ESPT) for a D‐π‐A Molecular Architecture
Authors: Hong Dan‐Li , Luo Yang‐Hui , He Xiao‐Tong , Zheng Zi‐Yue , Su Shan , Wang Jia‐Ying , Wang Cong , Chen Chen , Sun Bai‐Wang 
Published: May 2019

AbstractPrecise revealing the mechanisms of excited‐state intermolecular proton transfer (ESPT) and the corresponding geometrical relaxation upon photoexcitation and photoionization remains a formidable challenge. In this work, the compound (E)‐4‐(((4H‐1,2,4‐triazol‐4‐yl)imino)methyl)‐2,6‐dimethoxyphenol (TIMDP) adopting a D‐π‐A molecular architecture featuring a significant intramolecular charge transfer (ICT) effect has been designed. With the presence of perchloric acid (35 %), TIMDP can be dissolved through the formation of a HClO4–H2O–OH(TIMDP)–N(TIMDP) hydrogen‐bonding bridge. At the ground state, the ICT effect is dominant, giving birth to crystals of TIMDP. Upon external stimuli (e.g., UV light irradiation, electro field), the excited state is achieved, which weakens the ICT effect, and significantly promotes the ESPT effect along the hydrogen‐bonding bridge, resulting in crystals of [HTIMDP]+⋅[H2O]⋅[ClO4]−. As a consequence, the mechanisms of the ESPT can be investigated, which distorted the D‐π‐A molecular architecture, tuned the emission color with the largest Stokes shift of 242 nm, and finally, high photoluminescence quantum yields (12 %) and long fluorescence lifetimes (8.6 μs) have achieved. These results not only provide new insight into ESPT mechanisms, but also open a new avenue for the design of efficient ESPT emitters.
Radical‐Pair Formation in Hydrocarbon (Aut)Oxidation
Authors: Sandhiya Lakshmanan , Zipse Hendrik 
Published: May 2019

AbstractThe reaction profiles for the uni‐ and bimolecular decomposition of benzyl hydroperoxide have been studied in the context of initiation reactions for the (aut)oxidation of hydrocarbons. The unimolecular dissociation of benzyl hydroperoxide was found to proceed through the formation of a hydrogen‐bonded radical‐pair minimum located +181 kJ mol−1 above the hydroperoxide substrate and around 15 kJ mol−1 below the separated radical products. The reaction of toluene with benzyl hydroperoxide proceeds such that O−O bond homolysis is coupled with a C−H bond abstraction event in a single kinetic step. The enthalpic barrier of this molecule‐induced radical formation (MIRF) process is significantly lower than that of the unimolecular O−O bond cleavage. The same type of reaction is also possible in the self‐reaction between two benzyl hydroperoxide molecules forming benzyloxyl and hydroxyl radical pairs along with benzaldehyde and water as co‐products. In the product complexes formed in these MIRF reactions, both radicals connect to a centrally placed water molecule through hydrogen‐bonding interactions.
NMR Reveals That a Highly Reactive Nonheme FeIV=O Complex Retains Its Six‐Coordinate Geometry and S=1 State in Solution
Authors: Banerjee Saikat , Rasheed Waqas , Fan Ruixi , Draksharapu Apparao , Oloo Williamson N. , Guo Yisong , Que Lawrence 
Published: May 2019

AbstractThe [FeIV(O)(Me3NTB)]2+ (Me3NTB=tris[(1‐methyl‐benzimidazol‐2‐yl)methyl]amine) complex 1 has been shown by Mössbauer spectroscopy to have an S=1 ground state at 4 K, but is proposed to become an S=2 trigonal‐bipyramidal species at higher temperatures based on a DFT model to rationalize its very high C−H bond‐cleavage reactivity. In this work, 1H NMR spectroscopy was used to determine that 1 does not have C3‐symmetry in solution and is not an S=2 species. Our results show that 1 is unique among nonheme FeIV=O complexes in retaining its S=1 spin state and high reactivity at 193 K, providing evidence that S=1 FeIV=O complexes can be as reactive as their S=2 counterparts. This result emphasizes the need to identify factors besides the ground spin state of the FeIV=O center to rationalize nonheme oxoiron(IV) reactivity.
A multilevel graph approach for rainfall forecasting: A preliminary study case on London area
Authors: Clarizia Fabio , Colace Francesco , De Santo Massimo , Lombardi Marco , Pascale Francesco , Santaniello Domenico , Tuker Allan 
Published: May 2019

SummaryIncreasing populations and rapid large‐scale urbanization has created a demand to increase the quality of life through economic development, social stability, and better quality environments. These issues are addressed in the field of Smart Cities where, through the Internet of Things, efforts are being made to support added‐value services for the administration of the city and for citizens. The continuous exchange of information inevitably produces a huge amount of data, which demands analyses of data using unconventional methods within a Big Data context. How can we properly process these data? How can we properly use these data in order to increase the competitiveness and efficiency of services, and how could they contribute to social development? Services that could be useful in this field include Early Warning Systems. Information management environments, or more generally pervasive data contexts, may be supported by context representation approaches and enhanced through adopting probabilistic approaches such as Context Dimension Tree, Ontology, and Bayesian Network. The aim of this work is to introduce and explain a methodology for merging CDTs and Ontologies, and probabilistic approach based on BNs in order to help expert users handle emergencies and provide suggestions for improving the liveability of cities for their inhabitants.
Structural Transformation of 2,7‐Dibromopyrene on Au(111) Mediated by Halogen‐Bonding Motifs
Authors: Hu Jinbang , Shen Kongchao , Hu Jinping , Sun Haoliang , Tian Qiwei , Zhaofeng  , Liang  , Huang Han , Jiang Zheng , Wells Justin W. , Song Fei 
Published: May 2019

AbstractFundamental understanding of the bonding motifs that elaborately mediate the formation of supramolecular nanostructures is essential for the rational design of stable artificial organic architectures. Herein, the structural transformation of the adsorption complex of 2, 7‐dibromopyrene (Br2Py) on the Au(111) surface has been investigated by scanning tunnelling microscopy combined with X‐ray photoemission spectroscopy and density function theory calculations. In the initial stage of self‐assembly, well ordered patterns are formed in the manner of extended supramolecular structures balanced by intermolecular halogen bonding motifs, whilst the Au(111) reconstruction is still fairly visible. Subsequent thermal annealing promotes the dehalogenation and on‐surface Ullmann coupling, and polymerized oligomers are consequently constructed. Interestingly, such polymerized chains are still stably mediated by the halogen bonding motif via dissociated Br atoms which are revealed to be absorbed on the bridge site of Au(111), while the number of halogen bonds increases significantly from self‐assembly to Ullmann coupling polymerization, indicating that the halogen bonding motif contributes significantly to the extended one‐dimensional polymers.
Investigating Variation of the Pnicogen Nucleophilic Heteroatom on Ionic Liquid Solvent Effects in Bimolecular Nucleophilic Substitution Processes
Authors: Schaffarczyk McHale Karin S. , Haines Ronald S. , Harper Jason B. 
Published: May 2019

AbstractA series of nucleophiles containing Group 15 nucleophilic heteroatoms has been used to expand and develop the current understanding of ionic liquid solvent effects on bimolecular nucleophilic substitution processes. It was found that when using arsenic‐, antimony‐ and bismuth‐based nucleophiles, rate constant enhancement was observed for all solvent compositions containing ionic liquids. This rate constant enhancement was driven by ionic liquid/transition state interactions, which contrasts with previous studies on earlier Group 15 nucleophiles. This study provides a holistic understanding and augments the predictive framework for the effects of ionic liquids on bimolecular nucleophilic substitution processes, with the potential for these periodic trends to be broadly applied.
Diabatization by Localization in the Framework of Configuration Interaction Based on Floating Occupation Molecular Orbitals (FOMO−CI)
Authors: Accomasso Davide , Persico Maurizio , Granucci Giovanni 
Published: May 2019

AbstractWe present a diabatization method of general applicability, based on the localization of molecular orbitals on user specified groups of atoms. The method yields orthogonal molecular orbitals similar to the canonical ones for the isolated atom groups, that are the basis to build reference spin‐adapted configurations representing localized or charge transfer excitations. An orthogonal transformation from the adiabatic to the quasi‐diabatic basis is defined by requiring maximum overlap with the diabatic references. We present the diabatization algorithm as implemented in the framework of semiempirical configuration interaction based on floating occupation molecular orbitals (FOMO−CI), but the same transformation can also be applied to ab initio wavefunctions, obtained for instance with state‐average CASSCF. The diabatic representation so obtained and the associated hamiltonian matrix are particularly suited to assess quantitatively the interactions that account for charge and energy transfer transitions, and to analyze the results of nonadiabatic dynamics simulations involving such phenomena.