bluuebunny/crossref_metadata_2025_split huggingface dataset:
Über Antimon-haltige Heterocyclen, V Antimon(III)-dithiolate mit verbrückten 5-und 8-Ringen/On Heterocyclic Systems Containing Antimony, V Antimony(III) Dithiolates with Bridged 5-and 8 -Membered Rings
Authors: Hoffmann Harald M. , Dräger Martin 
Published: March 2015

Abstract
For diamony(III)-trisdithiolates two constitutions (bicyclic B or two bridged monocycles C) are possible. Two synthetical paths to three examples Sb2(XS2)3 with X = CH2CH2 (1), CH2CH2- O - CH2CH2 (2), CH2CH2- S - CH2CH2 (3) are reported. 13C NMR spectra in CDCl3 solution show the constitution C for 2 and 3, and a possible equilibrium C ⇌ 4:1) for 1. This corresponds to the result of a crystal structure analysis (R = 0.027). The constitution C found in solid 1 exhibits expanded coordination polyhedra around the two antimony atoms which indicate a starting point for rearrangement into the constitution B. The two bridged 5-membered rings have different conformations: envelope and half-chair.
Erdalkaliquadratate, I BaC4O4 · 3H2O / Alkaline-earth Squarates, I BaC4O4 · 3H2O
Authors: Robl Christian , Weiss Armin 
Published: March 2015

Abstract
BaC4O4-3H2O was prepared by crystallization in aqueous silica gel. The crystal structure is a complicated three-dimensional framework. Ba2+ has CN 8+1. It is surrounded by 5 water molecules and 4 Osquarate atoms (Ba-O distances from 271.1 to 324.2 pm). The squarate dianion is almost planar and shows C -C and C-O bond lengths indicating the existence of resonance stabilization, although one Osquarate atom is not connected to Ba2+ at all. Short water-Osquarate distances hint to strong hydrogen bonding which obviously plays an important part in this structure.
Übergangsmetallkomplexe mit Schwefelliganden, XXIII* Gekoppelte Alkylierungs-, Redox- und Substitutionsreaktionen an Metall-Schwefel-Zentren: Reaktionen von [Ru(PPh3)2dttd] mit Aziden RN3 und NEt4CN in CH2Cl2(dttd2-=2,3;8,9-Dibenzo-1,4,7,10-tetrathiadecan(-2); R=NEt4
+, [C(NH2)(NMe2)2]+, H+, Me3Si-) / Transition Metal Complex with Sulfur Ligands, XXIII*Coupled Alkylation, Redox and Substitution Reactions at Metal Sulfur Centers:Reactions of [Ru(PPh3)2dtt] with Azides RN3 and NEt4CN in CH2Cl2 (dttd2-=2,3;8,9-dibenzo-1,4,7,10-tetrathiadecane(-2); R=NEt4
+, [C(NH2)(NMe2)2]+, H+, Me3Si-)
Authors: Sellmann Dieter , Waeber Michael , Binder Herbert , Boese Roland 
Published: March 2015

Abstract
At the transition metal sulfur center of [Ru(PPh3)2dttd], (dud2- = 2,3;8,9-dibenzo-1,4,7,10- tetrathiadecane( -2)), the substitution of one PPh3 ligand by anions like N3
- or CN- in CH2Cl2 is always coupled with a chloromethylation of one thiolato S atom in dttd2- yielding the [dttd-CH2Cl]- ligand; with N3
- conversion of azido into cyano ligands takes place additionally. In the reaction of [Ru(PPh3)2dttd] with covalent azides like Me3SiN3 or HN3, the PPh3 substitution is also coupled with the oxidation of Ru(II) to Ru(III). Thus [Ru(PPh3)2dttd] on reaction with NEt4N3 or NEt4CN in boiling CH2Cl2 yields [Ru(PPh3)(L)(dttd-CH2Cl)], (L = N3
-, CN-), whereas with Me3SiN3 or HN3 in addition to [Ru(PPh3)(N3)(dttd-CH2Cl)] the paramagnetic (μeff = 1.58 B.M.) [Ru(PPh3)(N3)(dttd)] is obtained. The very stable [Ru(PPh3)(CN)(dttd-CH2Cl)] forms deeply coloured adducts with H+ as well as [CrCl3(THF)3], AlCl3 and BF3. With Mel it yields [Ru(PPh3)(CN)(Me-dttd-CH2Cl)]I. All compounds have been characterized by elemental analysis as well as spectroscopic means including ESCA; the structure of [Ru(PPh3)(CN)(dttd-CH2Cl)] has been solved by X-ray structure analysis.
An Alternative to the Mixed Probe Method in DNA Hybridization: Synthetic "lure" Nucleotide for the Ambiguous Position of Codons
Authors: Fukuda Tsunehiko , Hamana Takumi , Kikuchi Kaeko , Marumoto Ryuji 
Published: March 2015

Abstract
Two deoxynucleoside analogues, 1-(2-deoxy-β-D-ribofuranosyl)-2-oxo-4-imidazoline-4-carbox-amide (1) and 5-carbamoyl-2′-deoxyuridine (2), were synthesized and incorporated into decamer deoxynucleotides, which were hybridized to their complementary strands. The duplices in which 1 paired with A or G showed higher melting temperatures (Tm's) than those containing G -T or A -C mismatch, although lower than the Tm of intact totally complementary duplex. The incor­poration of 2 into a strand resulted in extreme destabilization of the duplex.
Synthesen und Kristallstrukturen der Kronenether-Komplexe (18-Krone-6) · 2CH3CN, [Na-15-Krone-5][ReO4] · CH3CN und [Na-15-Krone-5]PF6 / Syntheses and Crystal Structures of the Crown Ether Complexes (18-Crown-6) · 2 CH3CN, [Na-15-Crown-5][ReO4] · CH3CN, and [Na-15-Crown-5]PF6
Authors: Weller Frank , Borgholte Harald , Stenger Harald , Vogler Stefan , Dehnicke Kurt 
Published: March 2015

Single crystals of (18-crown-6) · 2 CH3CN were obtained by cooling a solution of 18-crown-6 in acetonitrile to 4 °C. Space group P21/n, Z = 2, 629 observed independent reflexions, R = 0.062. Lattice dimensions at 19°C: a = 911.7(1), b = 852.0(1), c = 1370.0(2) pm; β = 104.61(1)°. The compound forms a molecular structure with approximate D3d symmetry of the crown ether molecule, and C—H ··· O interactions of the acetonitrile molecules with the crown ether, the Η···Ο distances being 243, 253, and 267 pm, respectively.
[Na-15-crown-5][ReO4] · CH3CN is formed as a by-product of the reaction of ReNCl4 with sodium fluoride in acetonitrile in the presence of 15-crown-5 and traces of water. Space group Ρ 1̄ , Ζ = 2, 3107 observed independent reflexions, R = 0.045. Lattice dimensions at 19°C: a = 823.4(1), b = 1078.8(1), c = 1204.0(1) pm; α = 112.40(1)°, β = 94.35(1)°, γ = 104.63(1)°. The compound forms ion pairs, in which the sodium atom is sixfold coordinated by the five oxygen atoms of the crown ether molecule, as well as by one oxygen atom of the ReO4- ion, which is only slightly distorted. The bond length Na—OReO3 is 237.8(8) pm, the bond angle NaORe is 164.3(5)°.
[Na-15-crown-5]PF6 is formed in the reaction of [ReCl3(NSCl)2 · POC13] with sodium fluoride in acetonitrile solution in the presence of 15-crown-5. Space group Pna21, Ζ = 4, 1130 observed independent reflexions, R = 0.123. The high R value is due to disorder of the skeletal atoms of the crown ether molecule. The compound forms ion pairs, in which the sodium atom is sevenfold coordinated by the five oxygen atoms of the crown ether molecule, as well as by two fluorine atoms of the PF6
- ion with Na—F bond lengths of 240(2), and 246(2) pm, respectively.
Neue Untersuchung über Inhaltsstoffe aus Aloe- und Rhamnus-Arten, XIII [1] / A New Investigation on Constituents of Aloe and Rhamnus Species, XIII [1]
Authors: Rauwald Hans W. , Lohse Karsten , Bats Jan W. 
Published: March 2015

Rhamnus purshianus D. C., 10-Hydroxyaloins A/B, Oxanthrone Glucosyls, Quinonoids, Anthranoids
The absolute configurations of the diastereomeric 10-hydroxyaloins, which may be regarded as parent structures for other naturally occurring oxanthrone-C-glucosyls, have been established as 10R, 16 R (A) and 10 S, 16 R (B) by an X-ray structure analysis of the A-octaacetyl derivative (C 16 is the anomeric glucosyl carbon atom). The determination was confirmed by CD spectroscopic comparison with the structural analogues aloins A and B, which should prove useful for making future configurational assignments within this class of compounds. A conformational analysis by the use of a molecular modeling method based on force-field calculations reveals the presence of an extra- and an intra-form, the extra-form of which is energetically preferred.
Synthese und Kristallstruktur von Triphenylmethylphosphoniumtriiodid [P(C6H5)3CH3]I3 / Synthesis and Crystal Structure of [P(C6H5)3CH3]I3
Authors: El Essawi Mervat , Abd El Khalik Sawsan , Berthold H. J. , Wartchow R. 
Published: March 2015

Triphenylmethylphosphonium triiodide [P(C6H5)3CH3]I3 has been prepared by the reaction of [P(C6H5)3CH3]I with iodine in ethanol. Deep violet crystals were obtained by recrystallization from dichloromethane.
The crystal and molecular structure of the compound has been determined. The crystals are orthorhombic, space group Pbca, Z = 8, a = 1182.2(2), b = 1987.6(3), c = 1798.8(3) pm.
Least squares refinement of the structure yielded R = 0.038 (Rw = 0.030, RG = 0.030) for 2433 independent reflections.
The triodide ion I3
- is slightly asymmetrical and slightly bent. The distances are 293.7(1) pm (I(1)—I(2)) and 291.7(1) pm (I(2)—I(3)), the angle I(1)—I(2)—I(3) is 179.3(1)°.
The structure contains layers perpendicular to the c axis, which follow each other with a period of c/2 and are built up by I3
- anions and [P(C6H5)3CH3]+ cations. They are stacked to give layers of cations and layers of anions perpendicular to the b axis. The shortest I ··· I distance between I3
- ions in the anion layer occurs in the c direction. It amounts to 414 pm, thus indicating that there are only very weak I ··· I interactions between the I3
- ions. Further I ··· I contacts in the layer lie between 510 and 746 pm.
Übergangsmetallkomplexe mit Schwefelliganden, LXXII / Transition Metal Complexes with Sulfur Ligands, LXXII
Authors: Sellmann Dieter , Lechner Peter , Moll Matthias 
Published: March 2015

Racemic [Ru(ClH)(PPh3)′S4'] · CH2Cl2 (′S4'2-= 1,2-bis(2-mercaptophenylthio)ethane(2—)) reacts with monodentate sulfur ligands L to yield diastereospecifically yellow adducts [Ru(L)(PPh3)′S4']. Asymmetric achiral thioethers (L = SPhMe, CH3SSCH3) give only one of two potentially possible pairs of enantiomers, chiral thioethers and thiols (L = N-Acetyl-(L)-Methionin, N-Acetyl-(L)Methionin-methylester, S-Methyl-(L)Cystein, N-Acetyl-(L)Cystein) only two of four potentially possible diastereomers in the ratio 1:1.
These results prove that the diastereospecifity is related to the coordinated thioether or thiol sulfur atom: It becomes stereogenic in the course of coordination and its configuration is determined by the chirality of the [Ru(PPh3)′S4'] fragment. Additional stereogenic centres in the substituents of chiral thioethers or thiols do not enhance the degree of diastereoselectivity.
Selektive Additionsreaktionen an bifunktionalen neutralen Phosphenium-Ion-Komplexen / Selective Addition Reactions of Bifunctional Neutral Phosphenium Ion Complexes
Authors: Lang Heinrich , Leise Michael , Imhof Wolfgang 
Published: March 2015

The reaction of bifunctional neutral phosphenium ion complexes, containing a carbon-carbon triple bond next to a phosphorus-molybdenum multiple bond, with carbenes and to carbene isolobal organometallic fragments is discussed.
So, the reaction of (R)(PhC=C)P=MoCp′(CO), (R = 2,4,6-′Bu3C6H2O; Cp′ = η5-C5H5: la; Cp′ = η5-C5Me5: 1b) with CH2,Ν2 (2) yields the three membered heterocyclic compound

(3). 3 reacts with Co2(CO)8 to afford complex

(5) in which the phenylethynyl building block is η2-side-on coordinated to a Co2(CO)6 fragment. Similar to the reaction of 1 with 2, 1 forms with Fe2(CO)9 (6), compound

(7). In 7 the PMo double bond is coordinated in a η2 fashion to the 16-electron organometallic fragment Fe(CO)4. Using an excess of 6 and a higher temperature, the phosphorus-alkynyl-carbon σ-bond is cleaved, and cluster MoCp*Fe3(CO)8η3-PR)(C≡CPh) (8) is formed.
The reaction of 1 with Cr(CO)5(THF) yields 10, a complex, in which the PhC≡C ligand is η2-coordinated to Cp′(CO)2Mo, and the Cr(CO)5 group forms a dative bond with the phosphorus atom.
All new compounds have been characterized by analytical as well as by spectroscopic data (IR, 1H, 31P, 13C NMR, MS), compound 10 by an X-ray analysis.
Dinitrosylmolybdenum Complexes with Anion Ligands Coordinating by Oxygen Atoms. Synthesis, Electronic Structure and Olefin Metathesis Activity of Carboxylato-Dinitrosyl-Molybdenum Complexes
Authors: Keller Antoni , Szterenberg Ludmiła 
Published: March 2015

The new carboxylato-dinitrosyl-molybdenum complexes of the formula: [Mo(NO)2(O2CMe)2] • MeOH, Na2[Mo(NO)2(O2CMe)4] and Mo(NO)2(O2CPh)2 have been synthesized. Their structure was resolved on the basis of spectroscopic investigations (1H NMR, IR, UV-VIS). Catalytic activity of these complexes in olefin metathesis reaction was also examined.
The electronic structure of dinitrosyl-molybdenum complexes with ligands coordinating by oxygen atoms was calculated for the example of the di- and tetra-acetato-dinitrosyl-molybdenum complexes using the Fenske-Hall and INDO methods. To interpret the spectroscopic properties (UV-VIS) within the method of interaction configuration, the electronic structure of the excited states was calculated.
H2NNH- und H2NO- als η2-koordinierte Liganden in Tripod-Cobalt-Komplexen / H2NNH- and H2NO- as η2-Coordinated Ligands in Tripod Cobalt Complexes
Authors: Vogel Sabine , Huttner Gottfried , Zsolnai Laszlo , Emmerich Christiane 
Published: March 2015

The complex cation [tripod Co η2-(NH2O)]+, 2, (tripod = CH3C(CH2PPh2)3) containing an η2-coordinated NH2O−-ligand is an isoelectronic equivalent to the recently reported complex [tripod Co η2-(Ν2Η3)]+, 1, which contains side-on coordinated N2H3
− [1,4]. The structures of the two cations 1 and 2 are almost superimposable.
The structural discrimination between the NH2- and O- parts of the η2-NH2O--ligand in 2 has been corroborated by the synthesis and X-ray analysis of the cations [tripod Co η2-(NMe2O)]+, 3, and [tripod Co Cl (NH2OMe)]+, 4. The hydroxylamido(1–) compound 2 upon treatment with air transforms into the nitrosyl compound [tripod Co (NO)], 5, the structure of which has also been determined.
Na2[SnAs2], die erste Zintl-Phase mit einem [SnAs2]-Raumnetz aus adamantan-analogen [Sn4As10]-Einheiten / Na2[SnAs2], the First Zintl Phase with a [SnAs2] Framework Based on Adamantan Analogous [Sn4As10] Units
Authors: Asbrand Matthias , Eisenmann Brigitte 
Published: March 2015

The metallic grey compound Na2[SnAs2] was prepared from a molten mixture of the elements. Na2[SnAs2] crystallizes in the tetragonal space group I41/acd, Z = 32, with the lattice constants: a = 1416.6(3) pm, c = 2119.1(4) pm, c/a = 1.4959.
In the crystal structure four [SnAs4] tetrahedra are connected by common corners forming adamantan analogous [Sn4As10] units. The further connection of these tetrameric moieties by the terminal As atoms results in a three-dimensional framework ∞
3[SnAs2
2-], in which the Na atoms occupy distorted tetrahedral and octahedral holes.
Mathematical Modeling of Thermomechanical Stresses of Multilayer Erosion-Resistant Electrode Coatings of Magnetically Controlled MEMS
Authors: Karabanov Sergey , Suvorov Dmitriy , Gololobov Gennady , Slivkin Evgeny , Tarabrin Dmitry 
Published: March 2015

ABSTRACTThe paper presents the results of numerical modeling of thermomechanical stresses and thermal fields for conditions of erosion-resistant electrode coatings of magnetically controlled MEMS switches with W-Ti-Cu structure at local temperature and electric current influence in axially symmetrical approximation. It is shown that the introduction of titan interlayer (30-100 nm) in the coating with W-Ti-Cu structure results in considerable (more than two times) decrease of internal thermomechanical stresses between layers that increases coating resistance to delamination. It is established that there is an optimum value of Ti layer thickness at which the minimum thermomechanical stresses are provided.
Orthodontic marketing through social media networks: The patient and practitioner's perspective
Authors: Nelson Kristin L. , Shroff Bhavna , Best Al M. , Lindauer Steven J. 
Published: March 2015

ABSTRACT

Objective:
To (1) assess orthodontic patient and practitioner use of and preferences for social media and (2) investigate the potential benefit of social media in marketing and communication strategies in orthodontic practices.

Materials and Methods:
A survey was developed and randomly distributed to orthodontists via the American Association of Orthodontists and to patients/parents via private practices throughout the United States. Participants were asked to answer questions related to their use of social media and their perceptions of the use of social media in the orthodontic practice.

Results:
Of the participants, 76% of orthodontists and 89% of patients/parents use social media. Furthermore, Facebook was the social media platform that was most preferred. Social media use was more common in female and younger adult participants. Orthodontists posted information more often in the morning (40%) and afternoon (56%), and patients/parents used social media mainly in the evening (76%). The most commonly used marketing strategies in the orthodontic practices were social media (76%) and a practice website (59%). Social media and practice websites were positively related with new patient starts (P  =  .0376, P  =  .0035, respectively).

Conclusions:
Most orthodontists and patients/parents used social media. Social media may be an effective marketing and communication tool in an orthodontic practice.
Polyculture of juvenile pikeperch (Sander lucioperca (L.)) and sterlet (Acipenser ruthenus L.) in a recirculating system
Authors: Kozłowski Michał , Szczepkowski Mirosław , Wunderlich Krzysztof , Szczepkowska Bożena , Piotrowska Iwona 
Published: March 2015

Abstract
The experiment examined the possibility of rearing juvenile pikeperch, Sander lucioperca (L.) in polyculture with sterlet Acipenser ruthenus L. in a recirculating system. Three variants of pikeperch rearing were tested: monoculture (group S), with the addition of sterlet at 10% (group S10) and 20% (group S20) of the initial pikeperch biomass. After 56 days of rearing, no differences in the growth rates or survival of the pikeperch were noted. The value of the feed conversion ratio in the monoculture group was 1.19 and was significantly statistically higher than in the polyculture groups, the values of which were 0.84 (S10) and 0.74 (S20). The mean oxygen consumption and ammonia excretion values did not differ significantly statistically among the studied groups. Including the sterlet stock with the pikeperch permitted obtaining the additional value of the sterlet biomass using the same quantity of feed. Additionally, the inclusion of sterlet decreased the labor intensity of pikeperch rearing since the tanks did not need cleaning as frequently.
Strategies for the Adoption of Open Textbooks: The Latin American Open Textbooks Initiative
Authors: Rodés Virginia , Podetti Manuel , Hernández Yosly , Collazos Cesar 
Published: March 2015

Abstract
Open textbook initiatives have emerged as an alternative to traditional publications, boosting the creation of educational resources based on open licenses. In order to make them sustainable, it is necessary to define strategies for the adoption of these initiatives by the different actors involved in the education institutions where they will be implemented. In this article we present the components of the adoption strategy designed for the LATIn Initiative. In Section 2 we present the relevant background information collected in a state-of-the-art reviewing. We then present in Section 3 the components defined for the Strategy for the Adoption of the LATIn Project. In this respect, in Section 4 we present the main processes defined. Furthermore, in Section 5 we identify the intervention of Actors and Contexts. Finally, in Section 6 we include the Phases of Implementation of the strategy, defined as Initial Phase, Generalization Phase and Institutionalization Phase. In Section 7 we present the Conclusions of this work.
Self-Esteem and Loneliness as Factors Affecting Distance Learning Students
Authors: Vakoufari Maria , Christina Angelaki , Mavroidis Ilias 
Published: March 2015

Abstract
This study aims at empirically examining the relation of self-esteem and loneliness with social presence, academic performance, satisfaction with the course and intention for academic drop out, in a blended distance learning environment in Greece. The study involved both undergraduate and postgraduate students of the Hellenic Open University (HOU). Data were collected via a four-section questionnaire. The correlational data analysis yielded a negative correlation between self-esteem and intention for academic drop out, while there is a positive correlation between self-esteem and satisfaction derived from the course. Results also suggested that there is no correlation between self-esteem and academic performance. Findings also revealed that there is no statistically significant correlation between loneliness and the other variables under examination. Furthermore, the results showed that there were no statistically significant differences between the examined variables in relation to the demographic features (gender, age, etc.). The findings of the present study are discussed in relation to the relevant literature, taking into consideration the blended learning educational format offered by the HOU which is based on methodologies used in other European institutions that offer distance learning courses. Finally, recommendations for further research are presented.
A Responsive Paradigm for Technology Enhanced Learning (Tel) Integration Into Business Organizations
Authors: Kaminskienė Lina , Trepulė Elena , Rutkienė Aušra , Arbutavičius Gintaras 
Published: March 2015

Abstract
The purpose of this paper is to explore the main barriers and enablers for integrating technology enhanced learning (TEL) into a business organization based on a responsive paradigm. The study is based on a current literature review on challenges and learners’ needs for TEL and the preconditions for TEL curriculum integration into business organizations. The theoretical study is matched with a qualitative research on learners’ needs for TEL in two international business organizations from IT sector. Technology enhanced learning (TEL) is tackling different barriers for learning in organizations. However, to make it effective, specific technological and teaching solutions must be implemented. The research revealed that companies’ employees give preference to TEL than other forms of learning, and defined specific requirements for successful technology enhanced learning integration into business organisations. A theoretical literature review is followed by empirical findings of a qualitative research (focus group interviews) in two international IT companies. The findings of the research offer valuable insights for a responsive TEL integration into business organizations from the point of view of companies’ employees.
The Assessment Of The Risk Of Allergenicity Of ‘Sabina’ And ‘Debreceni Bötermö’ Sour Cherry Cvs (Prunus Cerasus L.) In A Guinea Pig Model
Authors: Jasińska-Stroschein Magdalena , Szcześniak Piotr , Owczarek Jacek , Rutkowski Krzysztof P. , Markowski Jarosław , Rozpara Elżbieta , Orszulak-Michalak Daria 
Published: March 2015

Abstract
The allergic reactions to fruits are lesser known among food sensitivities. The most common fruits belonging to the Rosaceae family that might cause allergic reactions are apples, pears and peaches. However, little is known about the potential allergic reactions caused by another member of the Rosaceae, the cherry. The aim of this study was to assess the risk of any allergic reaction or food hypersensitivity resulting from topical application and chronic oral administration of cherry fruits. The cherry fruits ‘Sabina’ cv. were produced in the orchard in Dąbrowice according to the principles of integrated (IFP) and organic (OR) productions. Fruits of ‘Debreceni Bötermö’ cv. were produced in Dąbrowice (IFP), and in the orchard in Nowy Dwór (OR). The experiments were performed on 65 outbred young, adult, white albinotic guinea pigs (Dankin Hartley). Three procedures were applied: I. Guinea-Pig Maximization Test (GPMT); II. Chronic administration of fruits and III. Skin prick (Dreborg) test. The skin reactions based on GPMT or Dreborg tests revealed no differences between the two cherry cultivars ‘Sabina’ and ‘Debreceni’ obtained from integrated or organic production. Similarly, it was not observed of any effect of cultivars of cherries nor the type of fruits production on the guinea pig skin reaction as a result of chronic feeding with fruits.