bluuebunny/crossref_metadata_2025_split huggingface dataset:
Energetic Properties of Rocket Propellants Evaluated through the Computational Determination of Heats of Formation of Nitrogen‐Rich Compounds
Authors: Forquet Valérian , Miró Sabaté Carles , Chermette Henry , Jacob Guy , Labarthe Émilie , Delalu Henri , Darwich Chaza 
Published: January 2016

AbstractThe use of ab initio and DFT methods to calculate the enthalpies of formation of solid ionic compounds is described. The results obtained from the calculations are then compared with those from experimental measurements on nitrogen‐rich salts of the 2,2‐dimethyltriazanium cation (DMTZ) synthesized in our laboratory and on other nitrogen‐rich ionic compounds. The importance of calculating accurate volumes and lattice enthalpies for the determination of heats of formation is also discussed. Furthermore, the crystal structure and hydrogen‐bonding networks of the nitroformate salt of the DMTZ cation is described in detail. Lastly, the theoretical heats of formation were used to calculate the specific impulses (Isp) of the salts of the DMTZ cation in view of a prospective application in propellant formulations.
Detection of Aβ Monomers and Oligomers: Early Diagnosis of Alzheimer's Disease
Authors: Zhou Yanli , Liu Lantao , Hao Yuanqiang , Xu Maotian 
Published: January 2016

AbstractAlzheimer's disease (AD), as the most common progressive neurodegenerative disorder, is pathologically characterized by deposition of extracellular plaque composed of amyloid‐β peptide (Aβ). Different assembled states of Aβ have been considered as both important biomarkers and drug targets for the diagnosis and therapy of AD. Recent studies demonstrate that small, diffusible Aβ oligomers formed by aggregation of Aβ monomers are the major toxic agents in AD. Therefore, the development of reliable assays for Aβ (both monomers and oligomers) will be important for the early differential diagnosis of dementia, predicting the progression of AD, as well as monitoring the effectiveness of novel anti‐Aβ drugs for AD. In this review, we summarize the recent progress made in the development of techniques for detection of Aβ monomers and oligomers. In particular, the principles governing the design of these sensors are classified and summarized. Moreover, the advantages and disadvantages of the assays are evaluated. This review also discusses the improvements and challenges for application of these assays in the early diagnosis of AD.
Catalytic Asymmetric Ring‐Opening Reactions of Aziridines with 3‐Aryl‐Oxindoles
Authors: Wang Linqing , Li Dan , Yang Dongxu , Wang Kezhou , Wang Jie , Wang Pengxin , Su Wu , Wang Rui 
Published: January 2016

AbstractA highly enantioselective ring‐opening alkylation reaction between 3‐aryl‐oxindole and N‐(2‐picolinoyl) aziridine has been realized for the first time. The reaction is efficiently mediated by a simple in‐situ‐generated magnesium catalyst and 3,3′‐fluorinated‐BINOL (BINOL=1,1′‐binaphthalene‐2,2′‐diol) has been identified as a powerful chiral ligand. Notably, the fluorine atom on the chiral ligand plays a key role in providing the desired chiral 3‐alkyl‐3‐aryl oxindoles with excellent enantioselectivities.
Palladium‐Catalyzed Site‐Selective C−H Functionalization of Weakly Coordinating Sulfonamides: Synthesis of Biaryl Sulfonamides
Authors: Vanjari Rajeshwer , Guntreddi Tirumaleswararao , Singh Krishna Nand 
Published: January 2016

AbstractA novel and site selective C−H functionalization of unsubstituted sulfonamides has been developed for the synthesis of ortho aryl sulfonamides. The reaction involves highly regioselective ortho mono arylation of weakly coordinating SO2NH2 directing group by means of aryl iodides. Palladium acetate in the presence of silver(I) oxide is found to be the most effective catalytic system.
Problem‐based learning applied to the artificial intelligence course
Authors: Fernandes Marcelo A. C. 
Published: January 2016

ABSTRACTThe purpose of this article is to present a problem‐based learning (PBL) proposal for use in the Artificial Intelligence course. The proposal includes problems associated with the area of mobile robotics, in which the student develops artificial intelligence solutions to optimize the movement of a robot in an unknown environment, avoiding obstacles. The proposed method was applied during three semesters (2012.1, 2013.1, and 2013.2), in the Applied Artificial Intelligence course of the Computational Engineering programme at the Federal University of Rio Grande do Norte. The results obtained in opinion surveys with the students during the three semesters are presented with the aim of validating the PBL proposal. The responses obtained in the opinion surveys show that the proposed method was well received, given that more than 80% of the responses were positive. Details of the implementation of the proposal are provided in order to assist others involved in the teaching of similar academic programme. © 2016 Wiley Periodicals, Inc. Comput Appl Eng Educ 24:388–399, 2016; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.21717
Predictors of early androgen deprivation treatment failure in prostate cancer with bone metastases
Authors: Varenhorst Eberhard , Klaff Rami , Berglund Anders , Hedlund Per Olov , Sandblom Gabriel ,   the Scandinavian Prostate Cancer Group (SPCG) Trial No. 5
Published: January 2016

AbstractApproximately 15% of men with hormone naïve metastatic prostate cancer primarily fail to respond to androgen deprivation treatment (ADT). The reason why the response to ADT differs in this subgroup of men with prostate cancer remains unclear. The aim of this study was to describe the characteristics of these men and to thereby define predictors of early ADT failure in prostate cancer patients with bone metastases. The study was based on 915 men from the prospective randomized multicenter trial (no. 5) conducted by the Scandinavian Prostate Cancer Group comparing parenteral estrogen with total androgen blockade. Early ADT failure was defined as death from metastatic prostate cancer within 12 months after the start of ADT. Multivariate logistic regression models were applied to identify clinical predictors of early ADT failure. Ninety‐four (10.3%) men were primarily nonresponders to ADT. Independent predictors of early ADT failure were poor Eastern Cooperative Oncology Group performance status (PS), analgesic consumption, low hemoglobin, and high Soloway score (extent of disease observed on the scan), in where patients with poor PS and/or high analgesic consumption had a threefold risk of early ADT failure. Not significantly factors related to early ADT failure were age, treatment, cardiovascular comorbidity, T category, grade of malignancy, serum estrogen level, and SHBG at enrolment. We analyzed characteristics of a subgroup of patients who primarily failed to respond to ADT. Four independent clinical predictors of early ADT failure could be defined, and men exhibiting these features should be considered for an alternative treatment.
New Caledonia: A ‘ Hot Spot’ for Valuable Chemodiversity
Authors: Coulerie Paul , Poullain Cyril 
Published: January 2016

AbstractThe flora of New Caledonia encompasses more than 3000 plant species and almost 80% are endemic. New Caledonia is considered as a ‘hot spot’ for biodiversity. With the current global loss of biodiversity and the fact that several drugs and pesticides become obsolete, there is an urgent need to increase sampling and research on new natural products. In this context, we review the chemical knowledge available on New Caledonian native flora from economical perspectives. We expect that a better knowledge of the economic potential of plant chemistry will encourage the plantation of native plants for the development of a sustainable economy which will participate in the conservation of biodiversity. In the second part of this review, we focus on the results exposed in 60 scientific articles and describe the identification of 225 original compounds from basal angiosperms and eudicot rosids. We discuss the economic potential of plants and molecules from medicinal and industrial perspectives. This review also highlights several plants and groups, such as Amborella sp., Piperaceae, or Phyllanthaceae, that are unexplored in New Caledonia despite their high chemical interest. Those plants are considered to have priority in future chemical investigations.
Loop‐Grafted Old Yellow Enzymes in the Bienzymatic Cascade Reduction of Allylic Alcohols
Authors: Reich Sabrina , Nestl Bettina M. , Hauer Bernhard 
Published: January 2016

AbstractThe enzymatic reduction of C=C bonds in allylic alcohols with Old Yellow Enzymes represents a challenging task, due to insufficient activation through the hydroxy group. In our work, we coupled an alcohol dehydrogenase with three wild‐type ene reductases—namely nicotinamide‐dependent cyclohex‐2‐en‐1‐one reductase (NCR) from Zymomonas mobilis, OYE1 from Saccharomyces pastorianus and morphinone reductase (MR) from Pseudomonas putida M10—and four rationally designed β/α loop variants of NCR in the bienzymatic cascade hydrogenation of allylic alcohols. Remarkably, the wild type of NCR was not able to catalyse the cascade reaction whereas MR and OYE1 demonstrated high to excellent activities. Through the rational loop grafting of two intrinsic β/α surface loop regions near the entrance of the active site of NCR with the corresponding loops from OYE1 or MR we successfully transferred the cascade reduction activity from one family member to another. Further we observed that loop grafting revealed certain influences on the interaction with the nicotinamide cofactor.
Endothelial function: The canary in the artery
Authors: Gilchrist Ian C. 
Published: January 2016

Key Points

Vascular dysfunction at the level of the brachial artery after transradial cardiac catheterization appears transient and resolves within a week
Chemo‐toxicity from procedural cocktails in addition to catheter‐mediated barotrauma directly to the brachial artery or indirectly from radial trauma may play a role in its etiology.
Further work is needed to better define the causes of vascular damage from the transradial procedures to develop safer techniques for the future.
In multivessel coronary artery disease, a “state‐of‐the‐art” randomized clinical trial of revascularization is needed
Authors: Bang Vigyan V. , Levy Michael S. 
Published: January 2016

Key Points

Based on this meta‐analysis of primarily observational data, complete revascularization (CR) is associated with a reduced risk of death, MI, and repeat revascularization in patients with multivessel coronary artery disease (MVCAD) as compared with incomplete revascularization (IR).
Given the current state of evidence, the likelihood of achieving complete revascularization should influence whether PCI or CABG is the best strategy in patients with MVCAD.
Given the lack of randomized trials in this area, more robust trial data will address the validity of these findings.
Successful recovery of tachycardia‐induced cardiomyopathy with severely depressed left ventricular systolic function by catheter ablation with mechanical hemodynamic support: a case report
Authors: Kamada Kazuhiro , Kubo Toshihiko , Sada Masashi , Ishikita Akihito , Tezuka Mika , Akiyama Yusuke , Umezu Ryuta , Ogawa Kiyohiro , Horimoto Koshin , Matsusaka Hidenori 
Published: January 2016

Key Clinical MessageWe describe the case that persistent atrial fibrillation refractory to rhythm control by pharmacotherapy and electrical cardioversions caused tachycardia‐induced cardiomyopathy with low ejection fraction and hemodynamic instability. Mechanical hemodynamic support using an intra‐aortic balloon pump is one of the choices of hemodynamic support during catheter ablation by pulmonary vein isolation.
Covalently Supported Ionic Liquid Phases: An Advanced Class of Recyclable Catalytic Systems
Authors: Giacalone Francesco , Gruttadauria Michelangelo 
Published: January 2016

AbstractIn this review, the most recent advances in the synthesis and catalytic applications of covalently supported ionic liquid (IL) phases will be discussed. This class of recyclable catalytic materials is based on the covalent attachment of several types of ammonium salts, usually imidazolium, but also thiazolium, triazolium, and pyrrolidinium salts, on the surface of different supports, for example, silica, periodic mesoporous organosilica, polystyrene, magnetic‐based materials, carbon nanotubes (NTs), halloysite NTs, polyhedral oligomeric silsesquioxane (POSS), and fullerenes. Moreover, poly(ionic liquid) materials, in which the IL‐based structure also acts as a support, will be considered. The synthetic applications of these materials will be presented, with special emphasis on their roles as catalysts, without added organocatalysts or metal‐based catalysts, as supports for organocatalysts, and as supports for metal‐based catalysts.
Enhancement of Dimethyl Carbonate Synthesis with In Situ Hydrolysis of 2,2‐Dimethoxy Propane
Authors: Wang Shengping , Zhou Jingjie , Zhao Shuyang , Zhao Yujun , Ma Xinbin 
Published: January 2016

AbstractThe direct synthesis of dimethyl carbonate (DMC) from CO2 and methanol is an attractive approach based on green chemistry. The influence of the addition of 2,2‐dimethoxy propane (DMP) on DMC formation was investigated over spindle‐CeO2, cube‐CeO2, and octahedron‐CeO2. Among these catalysts, spindle‐CeO2 showed a more favorable catalytic performance than the other CeO2 catalysts for the direct DMC synthesis with the addition of DMP. The yield of DMC was greatly improved by in situ removal of water from the reaction system through the addition of DMP. This indicated that hydrolysis of DMP overcomes the thermodynamic limitations of DMC formation and is highly effective for increasing the DMC yield. Thermodynamic calculations and the higher equilibrium constant supported this result.
Near‐Infrared Spectroscopy for Determination of the Biochemical Methane Potential: State of the Art
Authors: Ward Alastair J. 
Published: January 2016

AbstractThe use of near‐infrared spectroscopy (NIRS) for the determination of biogas and/or methane yields is a relatively new application of the technique. The accepted method of measuring the potential yield, the biochemical methane potential (BMP) test, involves the digestion of test substrates in an inoculum sourced from an active biogas reactor. The details of the BMP method vary, despite attempts at standardization. However, all the various methods are time consuming, with digestion times typically in the range of 30–100 days, and they are also rather labor intensive. The use of NIRS to predict gas yields can potentially cut this time to a matter of minutes and can even be implemented as an online measurement. But before NIRS can be used to give a reliable indication of true gas yields, there are many obstacles to be overcome, particularly regarding the uncertainty due to the poor standard error of laboratory of the reference method.
Benchmarking of Gas‐Assisted Atomization Systems for Liquid Disintegration
Authors: Günther Astrid , Lampa Aljoscha , Fritsching Udo , Schröder Jewe , Kleinhans Agnes , Gaukel Volker , Schuchmann Heike P. , Loth Jan‐Martin , Petermann Marcus , Wirth Karl‐Ernst 
Published: January 2016

AbstractFour different gas‐assisted atomizer systems are compared to assess their atomization performance for water and polymer solution feeds. An external mixing twin‐fluid atomizer serving as standard atomization configuration is compared to three rather unconventional atomization techniques. An internal mixing atomization system is represented by an effervescent atomizer that can be operated at lower air‐to‐liquid ratio than the conventional gas atomizers. Superheated atomization is an innovative technique to enhance the atomization of liquids by a phase change within the emerging spray. CO2‐assisted atomization takes the same line by releasing a liquid saturated with CO2 into a lower pressure environment. The atomization configurations were used to disintegrate the model fluid water and more challenging polymer solutions with higher viscosities. Resulting spray configurations and drop sizes distributions were compared.
Influence of Wetting on Washing and Filtration Properties
Authors: Burisch Markus , Peuker Urs A. 
Published: January 2016

AbstractThe washing of filter cakes represents a central part of material treatment and purification in science, research, and industry. The displacement washing aims at removing residues or at recovering the target liquid. This study focuses on systems with two immiscible liquids, thus the washing liquid forms a phase boundary with the pore liquid. By coating a solid model system with silanes, different surface energies on the surfaces can be achieved while all other granulometric properties remain unchanged. In addition to experimental investigation of the filtration and washing characteristics, the measurement of the contact angles quantifies the wetting behavior between the solid and the liquid phase.
Computational Fluid Dynamics Simulation of the Impact of Structure on the Degassing Efficiency of a Cyclone
Authors: Wang Chao‐yang , Yang Qiang , Xu Xiao , Wang Hua‐lin 
Published: January 2016

AbstractThe separation of liquid‐gas flows is essential for many industrial processes. Computational fluid dynamics including the algebraic slip mixture model and the Reynolds stress model is firstly adopted to analyze the impact of the number of inlets and the column diameter ratio on the degassing performance of a hydrocyclone. For separating the micrometer‐sized bubbles, the structures with one to six inlets and seven different column diameter ratios are simulated. The results show that multiport designs are more suitable for liquid‐gas separation, particularly for separation of small bubbles. However, as the number of inlets increases, the growth trend of separation efficiency is slowed. A longer column section is beneficial to small bubbles, but results in a greater loss of fluid energy.
Synergistic Effects of Cosolvents on the Dissolution of Wool Keratin Using Ionic Liquids
Authors: Wang Lijun , Nie Yi , Zhang Xiangping , Zeng Shaojuan , Zhang Suojiang , Zheng Shuangshuang 
Published: January 2016

AbstractKeratin, regenerated from wool fibers, is widely used in the textile and medicine fields. In this work, a series of synthesized 1‐butyl‐3‐methylimidazolium‐based ionic liquids (IL) were used to dissolve wool keratin. Among these IL, 1‐butyl‐3‐methylimidazolium dimethyl phosphate, [BMIM][DMP], is the best solvent; it can completely dissolve 5.0 wt % wool keratin in 10.5 h at 120 °C. In order to shorten the dissolution time, different cosolvents (sodium dodecyl sulfate, urea, and caprolactam) were utilized. Wool fibers at 5.0 wt % were dissolved under nitrogen within 4.5 h and a urea/[BMIM][DMP] mass ratio of 2.0 %, indicating that synergistic effects between the cosolvent and the IL can shorten the dissolution time. In addition, keratin regeneration was also studied. The results indicate that keratin regenerated in methanol shows better reproducibility and mechanical performance.
Influence of Temperature on Fluidized‐Bed Catalyst Attrition Behavior
Authors: Hao Jingai , Zhao Yinfeng , Ye Mao , Liu Zhongmin 
Published: January 2016

AbstractParticle attrition is a prevalent problem in fluidized beds due to continuous moving of catalyst particles. It is always operated at high temperature either for lab‐ or industrial‐scale fluidized beds. The influence of temperature on the attrition behavior of commercial methanol‐to‐olefins (MTO) and fluid catalytic cracking (FCC) catalysts is analyzed in a three‐orifice lab‐scale fluidized bed device from room temperature to 600 °C. The two catalysts are found to be alike in attrition mode. Both change from a combination of abrasion and fragmentation to main abrasion with increasing temperature, but differ greatly in the variation of attrition index with temperature which may be attributed to the difference of material and particle properties. An empirical correlation of attrition index to attrition temperature for all test samples is proposed.
One‐Pot Sequential Propargylation/Cycloisomerization: A Facile [4+2]‐Benzannulation Approach to Carbazoles
Authors: Raji Reddy Chada , Rani Valleti Reddi , Dilipkumar Uredi 
Published: January 2016

AbstractA novel one‐pot [4+2]‐benzannulation approach to substituted carbazoles is accomplished by acid‐catalyzed C3‐propargylation of 2‐alkenyl/aryl indoles with 1‐aryl propargylic alcohols, followed by cycloisomerization. A variety of 2‐alkenylated indoles and 2‐aryl/heteroaryl indoles successfully participated in this tandem reaction with 1‐aryl/heteroaryl propargylic alcohols to provide diversely substituted and annulated carbazoles, as well as an aza[5]helicene.
Triptycene‐Roofed Quinoxaline Cavitands for the Supramolecular Detection of BTEX in Air
Authors: Bertani Federico , Riboni Nicolò , Bianchi Federica , Brancatelli Giovanna , Sterner Elizabeth S. , Pinalli Roberta , Geremia Silvano , Swager Timothy M. , Dalcanale Enrico 
Published: January 2016

AbstractTwo novel triptycene quinoxaline cavitands (DiTriptyQxCav and MonoTriptyQxCav) have been designed, synthesized, and applied in the supramolecular detection of benzene, toluene, ethylbenzene, and xylenes (BTEX) in air. The complexation properties of the two cavitands towards aromatics in the solid state are strengthened by the presence of the triptycene moieties at the upper rim of the tetraquinoxaline walls, promoting the confinement of the aromatic hydrocarbons within the cavity. The two cavitands were used as fiber coatings for solid‐phase microextraction (SPME) BTEX monitoring in air. The best performances in terms of enrichment factors, selectivity, and LOD (limit of detection) values were obtained by using the DiTriptyQxCav coating. The corresponding SPME fiber was successfully tested under real urban monitoring conditions, outperforming the commercial divinylbenzene–Carboxen–polydimethylsiloxane (DVB–CAR–PDMS) fiber in BTEX adsorption.
Facile Construction of Structurally Defined Porous Membranes from Supramolecular Hexakistriphenylamine Metallacycles through Electropolymerization
Authors: Xu Xing‐Dong , Yao Chang‐Jiang , Chen Li‐Jun , Yin Guang‐Qiang , Zhong Yu‐Wu , Yang Hai‐Bo 
Published: January 2016

AbstractThe construction of well‐controlled porous materials is very challenging. Herein, we report the successful preparation of structurally defined porous membranes based on hexakistriphenylamine metallacycles through electropolymerization. The newly designed porous materials were characterized by the typical cyclic voltammograms, XPS, SEM, and TEM investigations. Further investigations revealed that the metallacycle‐based polymer films displayed a good size‐selective molecular‐sieving behavior.
Chemo‐ and Regioselective Reduction of 5,15‐Diazaporphyrins Providing Antiaromatic Azaporphyrinoids
Authors: Yamaji Ayaka , Tsurugi Hayato , Miyake Yoshihiro , Mashima Kazushi , Shinokubo Hiroshi 
Published: January 2016

AbstractReagent‐controlled chemo‐ and regioselective reduction of 5,15‐diazaporphyrins has been developed. The selective reduction of carbon–carbon double bonds of diazaporphyrins provides 18 π aromatic isobacteriochlorin‐type products, whereas the reduction of carbon–nitrogen double bonds leads to selective formation of 20 π N,N′‐dihydrodiazaporphyrins in excellent yields. The distinct antiaromatic character of N,N′‐dihydrodiazaporphyrins has been revealed. The free‐base N,N′‐dihydrodiazaporphyrin exhibits slower inner NH tautomerism than that in the corresponding 18 π porphyrins.
ChemInform Abstract: Crystal Structure of Tris(hydroxylammonium) Orthophosphate.
Authors: Leinemann Malte , Jess Inke , Boeckmann Jan , Naether Christian 
Published: January 2016

AbstractSingle crystals of (H3NOH)3PO4 are formed from a 1:3 molar mixture of H3PO4 and NH2OH upon cooling.