jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Zi‐Han Li | Yuan‐Qi Zhai | Weipeng Chen | You‐Song Ding | Yan-Zhen Zheng
Source: ChemRxiv (preprint, 2019-08-14)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Air-Stable Hexagonal Bipyramidal Dysprosium(III) Single-Ion Magnets with Nearly Perfect D6h Local Symmetry Local eight-coordination of the Dy(III) with D&lt;sub&gt;6h&lt;/sub&gt; symmetry receives much expectation for high-performance single-molecule magnets (SMMs) due to the simultaneous fulfillment of the magnetic axiality and high coordination number (a requisite for the air stability). But the experimental realization is challenging due to the required restriction of six coordination atoms in the equatorial plane of the hexagonal-bipyramid, which is usually too crowded for the central Dy(III) ion. Here we show by using the hexaaza macrocyclic Schiff base ligand and fine-tuning the axial alkoxide/phenol type ligands, a family of hexagonal-bipyramidal Dy(III) complexes, namely [Dy&lt;sup&gt;III&lt;/sup&gt;(L)(Cl)&lt;sub&gt;2&lt;/sub&gt;(H&lt;sub&gt;2&lt;/sub&gt;O/CH&lt;sub&gt;3&lt;/sub&gt;OH)]Cl &lt;b&gt;1&lt;/b&gt;, [Dy&lt;sup&gt;III&lt;/sup&gt;(L)(C&lt;sub&gt;6&lt;/sub&gt;F&lt;sub&gt;5&lt;/sub&gt;O)&lt;sub&gt;2&lt;/sub&gt;(H&lt;sub&gt;2&lt;/sub&gt;O)](BPh&lt;sub&gt;4&lt;/sub&gt;)·&lt;b&gt;2&lt;/b&gt;, [Dy&lt;sup&gt;III&lt;/sup&gt;(L)(PhO)&lt;sub&gt;2&lt;/sub&gt;](BPh&lt;sub&gt;4&lt;/sub&gt;) &lt;b&gt;3&lt;/b&gt;, [Dy&lt;sup&gt;III&lt;/sup&gt;(L)(4-MeO-PhO)&lt;sub&gt;2&lt;/sub&gt;](BPh&lt;sub&gt;4&lt;/sub&gt;) &lt;b&gt;4&lt;/b&gt;, [Dy&lt;sup&gt;III&lt;/sup&gt;(L)(naPhO)&lt;sub&gt;2&lt;/sub&gt;](BPh&lt;sub&gt;4&lt;/sub&gt;) &lt;b&gt;5 &lt;/b&gt;and [Dy&lt;sup&gt;III&lt;/sup&gt;(L)(Ph&lt;sub&gt;3&lt;/sub&gt;SiO)&lt;sub&gt;2&lt;/sub&gt;](BPh&lt;sub&gt;4&lt;/sub&gt;) &lt;b&gt;6&lt;/b&gt;&lt;b&gt; &lt;/b&gt;, can be isolated. Among them, complexes &lt;b&gt;3&lt;/b&gt;, &lt;b&gt;4&lt;/b&gt; and &lt;b&gt;5&lt;/b&gt; possess nearly perfect D&lt;sub&gt;6h&lt;/sub&gt; local symmetry. Complex &lt;b&gt;4&lt;/b&gt; shows the highest effective magnetic reversal barrier 1338 K and an open hysteresis temperature 6 K at the field sweeping rate of 1.2 mT/s, which represents a new record for D&lt;sub&gt;6h&lt;/sub&gt; SMMs. Crystallography ; Chemistry ; Dysprosium ; Coordination sphere ; Ligand (biochemistry) ; Pentagonal bipyramidal molecular geometry ; Stereochemistry ; Crystal structure ; Inorganic chemistry Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes ; Metal-Organic Frameworks: Synthesis and Applications
Authors: С. В. Босаков | О. В. Козунова
Source: Repository of Belarusian National Technical University (Belarusian National Technical University) (article, 2019-01-01)
Field: Materials Science — Materials Chemistry

Development of the theory of computation of pivotally-connected beams on an elastic foundation taking into account their physical nonlinearity This work presents a brief review of the literature on the theory and technique of computation of pivotally-connected structures on a linearly-elastic foundation. The authors refer to the works of B.G.Korenev, G.Ya.Popov, I.A.Simvulidi, R.V.Serebryany and A.G.Yuryev, in which investigations for calculating the pivotally-connected beams and slabs on an elastic foundation are performed using different approaches. From the analysis of the scientific and normative literature on the subject under consideration, a conclusion can be made that there is no common approach to solution of this problem, which would hold for any pivotally connected structures being in contact with any elastic foundation model under the action of an arbitrary external load. Besides, when designing the load carrying members of pavements of motor roads of various purposes in the Republic of Belarus, a number of branch-specific normative documents, where the pavements with the load carrying member and interconnection of members over the track length are considered separately in unconnected setting, is used. In this work, a universal approach for computation of pivotally-connected beams on an elastic foundation in the linear setting and taking into account the physical nonlinearity of the beam material is proposed. This approach is based on a mixed method of structural mechanics and implemented in different foundations taking into account the Zhemochkin’s relations for the functions of influences of an elastic medium. Foundation (evidence) ; Nonlinear system ; Computation ; Structural engineering ; Mathematics ; Computer science ; Engineering ; Physics ; Political science ; Algorithm ; Law Structural mechanics and materials ; Material Properties and Applications ; Advanced Theoretical and Applied Studies in Material Sciences and Geometry
Authors: David Chen | Yu-Kai David | Søbastien Vidal | Carolyn R. Bertozzi | Hongna Liu | S Lin | Kathryn H. Jacobsen | Thomas B. Poulsen | X. P. Xu | Sishen Xie | Y. Zhang | Peng He | J Molloy | T Orack | Ron Gilmour | Roger Proctor | R. H. Phipps | Peng Zhang | Xiang Han | Jianfeng Yao | Nannan Shao | K. Zhang | Yitong Zhou | Ying Zu | B Wang | Qin Li | John Shi | Jens Schneider | Bofeng Li | Lei Xie | Zhiqiang Wang | Shiping Chen | Hui-Li Ren | Yan Chen | Chao Wang | Guo Zhang | Jun Jiang | Cheng Zou | Jun Zhou | Xiaokang Yin | Zigang Dong | Amjad Ali | Zi‐Xia Song | Niraj Shrestha | Sandip S. Bista | Qing Bao | R. G. Ellingson | Yiren Yan | W. Tang | S. Sakamoto | Tadashi Sasaki | Ayana Tomita | Satoshi Takamizawa | Guo‐Ming Weng | Y. Xie | Huan Wang | Christopher Karpovich | Jeffrey H. Lipton | J. Zhu | Jie Kong | Lisa D. Pfefferle | Adam Taylor | B. Zheng | Guillaume Maurin | William Wan | A Li | B. T. Donovan | Hayley J. Fowler | Valentina M. Matavulj | Timothy O. White | Alexander S. Karns | B. L. Ellis | Philip Roosen | Zeinab Chahine | K Le Roch | Christopher D. Vanderwal | Thaksen Jadhav | Ang Y | W I Patterson | C.-H Liu | Ehsan Hamzehpoor | Dmitrii F. Perepichka | Ludivine Lebedel | A Ardμ | A Artin | J Døsirø | Agnès Martin‐Mingot | Marialuisa Aufiero | Núria Aiguabella Font | J J Imønez-Barbero | Y Bløriot | Sébastien Thibaudeau | Yang Zhang | Hui Chen | Weizhong Guo | Kun Jie | Y. Sun | Dongming Jiang | Ilja Popovs | Shuying Dai
Source: Angewandte Chemie International Edition (article, 2019-09-23)
Field: Chemistry — Organic Chemistry

Graphical Abstract: Angew. Chem. Int. Ed. 39/2019 from GDCh, Postfach 900440, D-60444 Frankfurt am Main, Germany. Citation ; INT ; Computer science ; Information retrieval ; Library science ; Programming language Radical Photochemical Reactions ; Click Chemistry and Applications ; Catalytic C–H Functionalization Methods
Authors: K Kohse-Hçinghaus | Harald Fuchs | Tengfei Zhang | Yilin Wu | Michael Brown | A. Paul Alivisatos | A. L. LIEBER | Wilhelm Exner | Joseph M. DeSimone | Ernst Schering | Sunisa Akkarasamiyo | Joseph S. M. Samec | P Mercier | Giacomo Reina | Li Zhao | Andrea Bianco | Norio Komatsu | Matthias Schiedel | Mustafa Moroglu | David M. H. Ascough | Alanna M. Chamberlain | Jaap Kamps | Angelina R. Sekirnik | Simon J. Conway | Zeyu Zhang | Nathaniel Corrigan | A Bagheri | Jian‐Ming Jin | Célia Boyer | Jan Mewes | Odile R. Smits | Georg Kresse | Patryk Przygocki | Piotr Ratajczak | F Bøguin | Christopher Anderson | Ning Dai | S.J. Teat | Bing He | Shuangyin Wang | Tom C. L. Bridge | Shafaque Shaikh | P. Thomas | Joaquín Botta | P. Aiden McCormick | Ashwin Sachdeva | Fei Li | X Li | Y Wang | Xiang Zhang | Miao Jin | Shūichi Yamamoto | Tomohiro Seki | Ito H | Miguel A. Garcı́a-Garibay | Nian Sun | Chao Wang | Huan Wang | Litheng Ng | Peiquan Jin | Weiqi Zhang | J Jiang | Marta Pacheco | B Jurado-Sμnchez | Alberto Escarpa | Z Li | Ge Wang | Y Ye | Bing Li | Hao Li | Bin Chen | Jie Zhao | K Li | K Wan | Tingting Sun | Ning Zheng | Feifei Zhu | Jianhua Ma | J. B. Jiao | Tianjiao Li | Juan Ni | X. Shi | Qi Peng | Jingwen Ai | W. Xu | S Liu | W. Jang | Jianmin Yun | Yi Liu | Nicolai Cramer | Junjie Yu | J .-J Li | Pengjie Wang | Jiahui Yu | Nan Wu | Shi Yan | Slobodan Lang | Jian‐Feng Zhou | J.-Y Iang | W Wang
Source: Angewandte Chemie International Edition (article, 2019-12-02)
Field: Chemistry — Organic Chemistry

Graphical Abstract: Angew. Chem. Int. Ed. 50/2019 can be found at www.gdch. Citation ; Computer science ; Information retrieval ; Library science Catalytic Cross-Coupling Reactions ; Cyclopropane Reaction Mechanisms ; Fluorine in Organic Chemistry
Authors: Mohammad Asif | Abida Abida | Touquir Alam
Source: Zenodo (CERN European Organization for Nuclear Research) (article, 2019-07-20)
Field: Chemistry — Organic Chemistry

An Overview on Execution of Green Chemistry as an Alternative Technique in Organic Synthesis <em>The implementation of green chemistry (GC) in various aspects of chemistry to overcome the problems of health, safety for workers, in addition to the environmental problems is associated with compounds from their manufacturing, use and disposition as waste. GC is a rapid promising branch of chemistry. GC is a manner that maximizes its benefits while removed its adverse impacts by the application of principles. The principles of GC focused on methods that deals with avoidance of waste, maximize atom economy, less harmful chemical formed, metathesis, synthesized safer chemicals, using safer solvents, auxiliaries, renewable Feedstocks, softer catalysts other than heavy metals, biocatalysts, avoid the formation of chemical derivatives, develop energy efficient synthesis, progress of safer chemistry methods for accident avoidance. GC is interested for research and alternative improvement on many practical phases of organic compounds synthesis. GC intended for less toxic solvents but in recent years new methods have been developed where organic synthesis can be performed without solvents, mild conditions and low energy consumption. New approaches have promoted the use of alternative methods or “green” solvents. The new field of “green” solvents in organic compounds synthesis has been extended and gives some idea about green solvent, green catalyst, and green techniques for green synthesis.</em> Chemistry ; Organic synthesis ; Biochemical engineering ; Computer science ; Nanotechnology ; Organic chemistry ; Engineering ; Materials science ; Catalysis Nanomaterials for catalytic reactions ; Asymmetric Hydrogenation and Catalysis ; Innovative Microfluidic and Catalytic Techniques Innovation
Authors: Matteo Zanda
Source: Synthesis (article, 2019-08-19)
Field: Chemistry — Organic Chemistry

SYNFORM ISSUE 2019/8 Today we had one of the two back-to-back University Open Days for prospective students and the campus was very busy with nearly 30,000 visitors -including guests, parents and guardians -on its premises. Chemistry ; Earth science ; Geology Synthesis of Tetrazole Derivatives ; Click Chemistry and Applications ; Multicomponent Synthesis of Heterocycles
Authors: Dawei Zhang | Tanya K. Ronson | Roy Lavendomme | Jonathan R. Nitschke
Source: Apollo (University of Cambridge) (article, 2019-11-18)
Field: Chemistry — Organic Chemistry

Selective Separation of Polyaromatic Hydrocarbons by Phase Transfer of Coordination Cages. Here we report a new supramolecular strategy for the selective separation of specific polycyclic aromatic hydrocarbons (PAHs) from mixtures. The use of a triethylene glycol-functionalized formylpyridine subcomponent allowed the construction of an FeII4L4 tetrahedron 1 that was capable of transferring between water and nitromethane layers, driven by anion metathesis. Cage 1 selectively encapsulated coronene from among a mixture of eight different types of PAHs in nitromethane, bringing it into a new nitromethane phase by transiting through an intermediate water phase. The bound coronene was released from 1 upon addition of benzene, and both the cage and the purified coronene could be separated via further phase separation. Nitromethane ; Coronene ; Chemistry ; Triethylene glycol ; Supramolecular chemistry ; Phase (matter) ; Benzene ; Dendrimer ; Photochemistry ; Organic chemistry ; Molecule Supramolecular Chemistry and Complexes ; Mass Spectrometry Techniques and Applications ; Metal-Organic Frameworks: Synthesis and Applications
Authors: Kristine L. Konkol
Source: NDSU Repository (North Dakota State University) (article, 2019-01-01)
Field: Chemistry — Organic Chemistry

Synthesis and Design of Thiophene Materials: Effects of Ring Fusion and Metal Coordination Conjugated organic materials comprise a field of materials chemistry focused on the development of semiconducting organic plastics, popular applications of which are plastic solar cells and display technologies. One of the reasons these materials have gained so much attention is that their optical and electronic properties can be tuned through engineering at the molecular level. Thiophene, an aromatic heterocycle, is a popular building block in the synthesis of many conjugated materials, prized for both the ease in which it can be synthetically functionalized and its ability to form highly conductive and low band gap materials. The Rasmussen group has previously reported on the generation of two classes of materials, the inorganic metal thiophenedithiolenes and the fused-ring heterocycle unit thieno[3,4-b]pyrazine (TP), both of which have applications in conducting materials. In an effort to expand upon the applicability and versatility of these materials, a series of interconnected projects were performed to further tune their optical, electronic, and physical (e.g. solubility) properties. This involved synthetic molecular design, including judicious consideration of structure-function relationships, and characterization of the resulting materials. Highlights include a sterics vs. electronics consideration of the catalyzed hydrodebromination of the molecular building-block 2,3,5-tribromothiophene, variation of the coordinating metal in thiophenedithiolenes to tune the optics and electronics, and characterization of the effects of ring-fusion on TP-based terthienyl homopolymers. Additionally, a new application of the TP monomer was found, whereby it was successfully incorporated as a bridging ligand into a multi-metallic Ru(II) supramolecular assembly, which demonstrated good metal-metal communication. Ring (chemistry) ; Thiophene ; Fusion ; Coordination complex ; Chemistry ; Metal ; Materials science ; Metallurgy ; Organic chemistry Organic Chemistry Cycloaddition Reactions ; Organometallic Compounds Synthesis and Characterization ; Catalysis and Hydrodesulfurization Studies
Authors: Isaac Sellinger
Source: CU Scholar (University of Colorado Boulder) (article, 2019-01-01)
Field: Materials Science — Materials Chemistry

Covalent Organic Frameworks as Customizable Vehicles for Controlled Drug Release This study explores the use of covalent organic frameworks (COFs) as drug carriers that can be modified and customized for non-toxic, resilient, controllable drug delivery applications. We identified COFs as a possible polymer candidate among other porous polymers and reviewed the literature to design a preliminary study investigating the toxicity, stability, and controlled drug delivery property of COFs. In this study, we selected COF-Ph (COF1) as the reference COF and compared its performance to that of COF-TpPa (COF2), and COF-TfpbPa (COF3) to understand the effect of hydrophobicity/hydrophilicity and pore size on their drug release. Ibuprofen (IBU) was selected as the target drug for loading and release experiments given its prevalence in release studies reported in previous literature. IBU was loaded into each COF and released into a phosphate buffer solution (PBS). Release profiles for each COF were characterized by nanodrop UV-vis. The stability, loading, and porosity of COFs were characterized by powder x-ray diffraction (PXRD) and N2 adsorption/desorption isotherms with Brunauer-Emmett-Teller (BET) analysis. Toxicity was evaluated by treating HeLa human cervical cancer cells with COFs of varied concentrations. At the end of this project, no solid conclusion can be drawn, and more questions arose than what was answered yet suggestive conclusions were distilled. COFs with different structures have different characteristics for drug delivery. COFs’ toxicity is likely dependent on intra and extracellular interactions with the COF. COFs are likely stable through release into PBS, but their porosity and crystallinity may change throughout the experiment and differ from batch to batch. This study is the beginning of a project whose goal is to develop a controllable drug delivery system that can be used to match patients’ metabolism, significantly extending and controlling the release time and location, thus creating an opportunity for shifting the medication from patient administration of standard medications to professionally administered personalized medicines. Business ; Drug ; Chemistry ; Computer science ; Process management ; Pharmacology ; Medicine Covalent Organic Framework Applications ; Chemical Synthesis and Reactions ; Innovative Microfluidic and Catalytic Techniques Innovation
Authors: Shuai Yuan | Jiayu Peng | Yirui Zhang | Yang Shao‐Horn
Source: DSpace@MIT (Massachusetts Institute of Technology) (article, 2019-01-01)
Field: Chemistry — Inorganic Chemistry

Stability Trend of Metal–Organic Frameworks with Heterometal-Modified Hexanuclear Zr Building Units Bimetallic metal–organic frameworks (MOFs) based on heterometal-modified hexanuclear Zr building units have emerged as promising materials for applications in energy-related fields such as heterogenous catalysis/electrocatalysis. However, their stability remains a challenge under some practical conditions, and the physical/chemical origin to the (in)stability is not well-understood. Herein, we selected three representative Zr-MOFs (MOF-808, NU-1000, and UiO-66) as platforms and incorporated different heterometals (Ti4+, V3+, V5+, Cr3+, Cr6+, Mn2+, Fe2+, Fe3+, Co2+, Ni2+, Cu2+, and Zn2+) to form a series of bimetallic M/Zr-MOFs. Their stability was examined in aqueous solutions of various pH to define their stability windows and understand their stability trend. The stability of M/Zr-MOFs was found to be dictated by the oxidation states of incorporated heterometals and slightly affected by the supporting Zr-MOFs. Water-exchange rate constant, defined as the rate constant by replacing a coordinated water with a solution water, was proposed as the stability descriptor to explain the stability trend and guide the design and application of future stable MOFs. Bimetallic strip ; Chemistry ; Stability (learning theory) ; Aqueous solution ; Metal-organic framework ; Chemical stability ; Reaction rate constant ; Catalysis ; Transition metal ; Metal ; Chemical engineering ; Nanotechnology ; Physical chemistry ; Kinetics ; Organic chemistry ; Materials science ; Computer science Metal-Organic Frameworks: Synthesis and Applications ; Magnetism in coordination complexes ; Catalysis and Hydrodesulfurization Studies
Authors: Dong Li | Pingping Deng | Li Wu
Source: Zeitschrift für Kristallographie - New Crystal Structures (article, 2019-04-21)
Field: Chemistry — Inorganic Chemistry

Crystal structure of <i>catena</i>-poly[(μ<sub>2</sub>-azido-κ<sup>2</sup> <i>N</i>:<i>N</i>)(μ<sub>2</sub>-4-cyanobenzoato-κ<sup>2</sup> <i>O</i>:<i>O′</i>)-(μ<sub>2</sub>-methanol-κ<sup>2</sup> <i>O</i>:<i>O</i>)copper(II)], C<sub>9</sub>H<sub>8</sub>CuN<sub>4</sub>O<sub>3</sub> Abstract C 9 H 8 CuN 4 O 3 , triclinic, P 1̄ (no. 2), a = 6.3568(4) Å, b = 8.8323(6) Å, c = 10.8584(7) Å, α = 103.891(1)°, β = 94.868(1)°, γ = 105.453(1)°, V = 563.16(6) Å 3 , Z = 2, R gt ( F ) = 0.0245, wR ref ( F 2 ) = 0.0701, T = 296(2) K. Triclinic crystal system ; Crystallography ; Crystal structure ; Physics ; Crystal (programming language) ; Chemistry ; Computer science Metal-Organic Frameworks: Synthesis and Applications ; Magnetism in coordination complexes ; Lanthanide and Transition Metal Complexes
Authors: Derek I. Wozniak | Andrew J. Hicks | William A. Sabbers | Graham E. Dobereiner
Source: ChemRxiv (preprint, 2019-07-08)
Field: Materials Science — Materials Chemistry

Imidazolyl-Phenyl (IMP) Anions: A Modular Structure for Tuning Solubility and Coordinating Ability The effect of counteranion upon a cation’s solution-phase reactivity depends on a subtle interplay of weak interactions. Although these effects are widely appreciated in synthesis and catalysis, probing and controlling anion-cation interactions remains a significant challenge. Here we report the synthesis, characterization and reactivity of the IMP anions, a family of anions with a coordinating ability that can be tuned for a given application. The anions are robust, compatible with both strongly basic and acidic media, suitable for isolation of unstable organometallic species, and effective as counteranions for homogeneous catalysis. IMP anions are prepared in two steps: deprotonation of substituted 2-phenylimidazoles with NaH, followed by addition of 2 equiv. B(C6F5)3. The anions prepared feature a range of functionality, including nitro, ester, amide, amine and alcohol groups. Based on the spectroscopic properties of [Pd(IPr)(C(O)C9H6N)] [IMP-R], the coordinating ability of [IMP-R]− ranges between BF4− and BArF4−, depending on the polarity of the R group. Gold complexes of type [L-Au-L’][IMP-R] have been isolated and characterized, resulting in the first X-ray structure of a (eta-2-diphenylacetylene)Au complex. [(tBuXPhos)Au(MeCN)][IMP-R] catalyzes [2+2] cyclization of alkenes and alkynes, as well as the hydroalkoxylation of alkynes. Unlike SbF6− and BArF4−, the [IMP-H]− and [IMP-CF3]− salts are sufficiently soluble to efficiently promote cyclizations in toluene with [(tBuXPhos)Au(MeCN)]+. Chemistry ; Deprotonation ; Reactivity (psychology) ; Toluene ; Catalysis ; Amide ; Medicinal chemistry ; Stereochemistry ; Amine gas treating ; Diphenylacetylene ; Combinatorial chemistry ; Ion ; Organic chemistry Nanocluster Synthesis and Applications ; Asymmetric Hydrogenation and Catalysis ; Catalytic Alkyne Reactions
Authors: Pál Sipos | István Pálinkó
Source: Studia Universitatis Babeș-Bolyai Chemia (article, 2019-09-30)
Field: Materials Science — Materials Chemistry

LAYERED DOUBLE HYDROXIDES, PECULIAR AND VERSATILE MATERIALS OFFERING MANY RESEARCH AND APPLICATION POSSIBILITIES This review article describes the major structural features of layer double hydroxides (LDHs), gives an overview of their synthetic and modification methods as well as the structural characterization possibilities both the generally used and those, which can only be used for specific LDHs. The catalytic use of these materials without calcination, i.e. the layered structure is preserved, are also highlighted. The paper places the authors’ works of about the last decade in the framework of recent papers and review articles of this broad field. Layered double hydroxides ; Calcination ; Characterization (materials science) ; Nanotechnology ; Materials science ; Computer science ; Engineering ; Catalysis ; Chemistry ; Chemical engineering ; Organic chemistry ; Hydroxide Layered Double Hydroxides Synthesis and Applications ; Polyoxometalates: Synthesis and Applications ; Magnesium Oxide Properties and Applications