Temperature-dependent halogen⋯halogen synthon crossover in coordination compounds

CrystEngComm ◽  
2014 ◽  
Vol 16 (36) ◽  
pp. 8479-8485 ◽  
Author(s):  
Hamid Reza Khavasi ◽  
Maryam Esmaeili
Keyword(s):  
Coordination Compounds ◽  
Type I ◽  
Type Ii ◽  
Temperature Dependent ◽  
First Time

The crossover between type I and type II Br⋯Br synthons on the formation of coordination compounds has been investigated for the first time.

Transport Properties of Type II Sodium-Silicon Clathrates

2005 ◽  
Vol 886 ◽  
Author(s):  
Matt Beekman ◽  
Jan Grkyo ◽  
George S. Nolas
Keyword(s):  
Thermal Conductivity ◽  
Sodium Content ◽  
Type I ◽  
Type Ii ◽  
Conductivity Measurements ◽  
Scanning Calorimetry ◽  
Resistivity Measurements ◽  
Silicon Clathrates ◽  
Covalently Bonded ◽  
First Time

ABSTRACTWe have synthesized the type II silicon clathrates Na1Si136 and Na8Si136, and report on the electrical and thermal transport in these materials. The crystal structure consists of a covalently bonded silicon framework in which sodium guest atoms are encapsulated inside the silicon host framework. Differential scanning calorimetry measurements show the compounds decompose above 600°C to diamond-structure silicon. Temperature dependant electrical resistivity measurements show the specimens to have an insulating character, with magnitudes that decrease with increasing sodium content. For the first time, thermal conductivity measurements on type II sodium-silicon clathrates are presented. The thermal conductivity is very low for both specimens, and for Na8Si136 exhibits a clear dip in the range from 50 to 70 K. These data suggest that the “rattling” behavior observed in type I clathrates may also be present in type II clathrates.

Temperature dependent spectral properties of type-I and quasi type-II CdSe/CdS dot-in-rod nanocrystals

2012 ◽  
Vol 14 (10) ◽  
pp. 3505 ◽  
Author(s):  
Xiaoming Wen ◽  
Amit Sitt ◽  
Pyng Yu ◽  
Yon-Rui Toh ◽  
Jau Tang
Keyword(s):  
Spectral Properties ◽  
Type I ◽  
Type Ii ◽  
Temperature Dependent

scholarly journals CLEAR AS MUD: THE TYPE I/TYPE II MODEL FOR DEATH RECEPTOR-INDUCED APOPTOSIS

2006 ◽  
Vol 43 (2) ◽  
Author(s):  
David Michael Conrad
Keyword(s):  
Death Receptor ◽  
Mitochondrial Pathway ◽  
Type I ◽  
Biological Processes ◽  
Type Ii ◽  
Type Ii Cell ◽  
Mort Cellulaire ◽  
Induced Apoptosis ◽  
First Time ◽  
The Relationship

Apoptosis is a highly organized form of cell death that plays an important regulatory role in many biological processes. The relationship between the two classical signalling pathways of apoptosis, the “death receptor” and “mitochondrial” pathways, was only vaguely appreciated until 1998, when death receptor pathway-mediated activation of the mitochondrial pathway was clearly demonstrated for the first time. The “type I/type II” model of death receptor-mediated apoptosis was proposed and subsequently adopted for use in categorizing cells according to the involvement of the mitochondrion duringdeath receptor-induced apoptosis. Since that time, however, different interpretations of the type I/type II cell definition have appeared in the literature and, consequently, the meaning of type I and type II cells has become less clear.L’apoptose est une forme de mort cellulaire très structurée qui joue un rôle important de régulation dans un grand nombre de processus biologiques. La relation entre les deux voies de signalisation traditionnelles de l’apoptose, la voie des « récepteurs de mort » et la voie mitochondriale, n’était connue que vaguement avant 1998, l'année où l’activation de la voie mitochondriale par l’intermédiaire de la voie des récepteurs de mort a été clairement démontrée pour la première fois. Le modèle « type I / type II » d’apoptose par l’intermédiaire des récepteurs de mort a été proposé puis adopté auxfins de catégorisation des cellules en fonction de la participation des mitochondries à cette apoptose. Depuis, différentes interprétations ont toutefois été formulées dans des ouvrages scientifiques quant à la définition des cellules de type I et de type II et, par conséquent, la signification de « cellules de type I » et de « cellules de type II » est devenue moins évidente.

Electron Staining Characteristics of the Inclusion Bodies of Type II Alveolar Epithelial Cells

1968 ◽  
Vol 26 ◽  
pp. 46-47
Author(s):  
Yutaka Kikkawa ◽  
Ho-Soon Hahn
Keyword(s):  
Epithelial Cells ◽  
Inclusion Bodies ◽  
Alveolar Epithelial Cells ◽  
Type I ◽  
Type Ii ◽  
Colloidal Iron ◽  
Alveolar Epithelial ◽  
Mammalian Lung ◽  
First Time ◽  
Electron Lucent

The inclusion bodies of Type II epithelial cells of the mammalian lung are oval and limited by a unit membrane. They contain highly osmiophilic material. With the standard method of fixation this material is irregularly separated by a number of electron-lucent spaces (Figure 1). Because of this appearance, the inclusion bodies are often referred to as “lamellar inclusions”. Measurable periodic lamellae, however, have never been observed in the inclusions which are located intracellularly.During the course of the studies to localize acid mucopolysaccharides in the distal air way of the rabbit and rat, it is found that the alveolar surface of the cell membranes of both Type I and II cells and the inclusion bodies within Type II cells satin heavily with colloidal iron at pH 2.0 following the osmication of the tissue with phosphate-buffered solution at pH 7.4 (Figure 2). In addition, the inclusion bodies for the first time show regular periodic lamellae. Each line is granular and measures about 60 Å in width (Figure 3).

Thermal Conductiviy of type I and II Clathrate Compounds

2000 ◽  
Vol 626 ◽  
Author(s):  
G.S. Nolas ◽  
J.L. Cohn ◽  
M. Kaeser ◽  
T.M. Tritt
Keyword(s):  
Thermal Conductivity ◽  
Type I ◽  
Lattice Structures ◽  
Type Ii ◽  
Clathrate Compounds ◽  
Materials Research ◽  
Small Band ◽  
Semiconducting Compounds ◽  
First Time ◽  
Type Crystal

ABSTRACTCompounds with clathrate-hydrate type crystal lattice structures are currently of interest in thermoelectric materials research. This is due to the fact that semiconducting compounds can be synthesized with varying doping levels while possessing low, even ‘glass-like’, thermal conductivity. Up to now most of the work has focused on type I Si and Ge clathrates. Sn-clathrates however are viewed as having the greatest potential for thermoelectric cooling applications due to the larger mass of Sn and the expected small band-gap, as compared to Si and Ge clathrates. Transport properties on type I Sn-clathrates has only recently been reported [1–3]. In this report we present ongoing experimental research on both type I and II clathrates with an emphasis on the thermal transport of these novel materials. We present thermal conductivity data Si-Ge and Ge-Sn alloys as well as on a type II Ge clathrate for the first time, and compare these data to that of other clathrate compounds.

scholarly journals Evolution of co-regulatory network of C4 metabolic genes and TFs in the genus Flaveria: go anear or away in the intermediate species?

2020 ◽  
Author(s):  
Ming-Ju Amy Lyu ◽  
Jemaa Essemine ◽  
Faming Chen ◽  
Genyun Chen ◽  
Xin-Guang Zhu
Keyword(s):  
Regulatory Network ◽  
Regulatory Networks ◽  
Evolutionary Process ◽  
Type I ◽  
Type Ii ◽  
Intermediate Species ◽  
Closely Related Species ◽  
Metabolic Genes ◽  
Species Specific ◽  
First Time

AbstractC4 photosynthesis evolved from the ancestral C3 photosynthesis by recruiting pre-existing genes to fulfill new functions. The enzymes and transporters required for the C4 photosynthesis have been intensively studied; however, the transcription factors (TFs) regulating these C4 metabolic genes are not well understood. In particular, how the TF regulatory network of C4 metabolic genes was rewired during the evolution is unclear. Here, we constructed TFs co-regulatory networks for core C4 metabolic genes (C4GRN) for four evolutionarily closely related species from the genus Flaveria, which represent four different evolutionary stages of the C4 photosynthesis, namely, C3, type I C3-C4, type II C3-C4 and C4. Our results show that more than half of the co-regulations of TFs and C4 core metabolic genes were species specific. The counterparts of C4 genes in C3 species were already co-regulated with the photosynthesis-related genes; whereas the required TFs for the C4 photosynthesis were recruited later. The type I C3-C4 species recruited 40% of C4 required TFs which co-regulated all core C4 metabolic genes but PEPC; nevertheless, the type II C3-C4 species took on a high divergent C4GRN with C4 species itself. In C4 species, PEPC and PPDK-RP possessed much more co-regulated TFs than other C4 metabolic genes. This study provides for the first time the TFs profiles of the C4 metabolic genes in species with different photosynthetic types and reveal the dynamic of C4 genes-TFs co-regulations along the evolutionary process, providing thereby new insights into the evolution of C4 photosynthesis.

scholarly journals Spectroscopy and Photometry of the Least Massive Type II Globular Clusters: NGC 1261 and NGC 6934*

2021 ◽  
Vol 923 (1) ◽  
pp. 22
Author(s):  
A. F. Marino ◽  
A. P. Milone ◽  
A. Renzini ◽  
D. Yong ◽  
M. Asplund ◽  
...  
Keyword(s):  
Neutron Capture ◽  
Globular Clusters ◽  
Dwarf Galaxy ◽  
Slow Neutron ◽  
Type I ◽  
Type Ii ◽  
Chemical Abundances ◽  
Red Giant ◽  
First Time ◽  
Massive Clusters

Abstract Recent work has revealed two classes of globular clusters (GCs), dubbed Type I and Type II. Type II GCs are characterized by both a blue and a red red giant branch composed of stars with different metallicities, often coupled with distinct abundances in the slow neutron-capture elements (s-elements). Here we continue the chemical tagging of Type II GCs by adding the two least massive clusters of this class, NGC 1261 and NGC 6934. Based on both spectroscopy and photometry, we find red stars in NGC 1261 to be slightly enhanced in [Fe/H] by ∼0.1 dex and confirm that red stars of NGC 6934 are enhanced in iron by ∼0.2 dex. Neither NGC 1261 nor NGC 6934 show internal variations in the s-elements, which suggests a GC mass threshold for the occurrence of s-process enrichment. We found a significant correlation between the additional Fe locked in the red stars of Type II GCs and the present-day mass of the cluster. Nevertheless, most Type II GCs retained a small fraction of Fe produced by SNe II, lower than the 2%; NGC 6273, M54, and ω Centauri are remarkable exceptions. In the Appendix, we infer for the first time chemical abundances of lanthanum, assumed as representative of the s-elements, in M54, the GC located in the nucleus of the Sagittarius dwarf galaxy. Red-sequence stars are marginally enhanced in [La/Fe] by 0.10 ± 0.06 dex, in contrast with the large [La/Fe] spread of most Type II GCs. We suggest that different processes are responsible for the enrichment in iron and s-elements in Type II GCs.

Studien zum Vorgang der Wasserstoffübertragung, 72 [1] Versuche zur enantioselektiven Homogenhydrierung von N-Acyl-α-aminozimtsäuren mit Rh(I)-Komplexen unter Verwendung neuer optisch aktiver Co-Katalysatoren/Studies on the Occurrence of Hydrogen Transfer, 72, [1] Investigation on the Enantioselective Homogeneous Hydrogenation of N-Acyl-α-aminocinnamic Acids with Rh(I)-Complexes Using New Optically Active Co-Catalysts

1984 ◽  
Vol 39 (4) ◽  
pp. 512-516 ◽  
Author(s):  
L. Horner ◽  
G. Simons
Keyword(s):  
Hydrogen Transfer ◽  
Optically Active ◽  
Type I ◽  
Type Ii ◽  
Homogeneous Hydrogenation ◽  
Active Compounds ◽  
Co Catalyst ◽  
Co Catalysts ◽  
Optical Induction ◽  
First Time

3 Optically active compounds of the type I and 15 optically active compounds of the type II were investigated as co-catalysts in the homogeneous hydrogenation of N-acyl-α-aminocinnamic acids using standard conditions. In the co-catalysts of the type I the phosphorus atom is the center of the asymmetry. In the representatives of type II the side chain is optically active and the three bonded phosphorus either achiral or optically active.The results of the homogeneous hydrogenation are deposited in the Tables I-IV. In the Tables I and IV the degree of the optical induction and the configuration of the excess enantiomer are determined using Rh/P-ratios 1:1,1 and 1:2,2. The Tables II and III show the results applying a Rh/P-ratio of 1:2,2. The observed degree of optical induction is low with the co-catalysts 1-18; only the co-catalyst 19 shows an optical induction of 68%. A change of the configuration of the excess enantiomer of N-benzoylphenylalanine formed by the homogeneous hydrogenation of N-benzoyl-α-cinnamic acid for the first time was observed by varying the Rh/P-ratio of the co-catalysts 14, 17 and 18 from 1:1,1 to 1:2,2.

scholarly journals Transport Characteristics of Fujifilm Ion-Exchange Membranes as Compared to Homogeneous Membranes АМХ and СМХ and to Heterogeneous Membranes MK-40 and MA-41

Membranes ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 84 ◽  
Author(s):  
Sarapulova ◽  
Shkorkina ◽  
Mareev ◽  
Pismenskaya ◽  
Kononenko ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Volume Fraction ◽  
Transport Numbers ◽  
Type I ◽  
Type Ii ◽  
Ion Exchange Membranes ◽  
Electrospinning Method ◽  
Microheterogeneous Model ◽  
First Time

Ion-exchange membranes (IEMs) find more and more applications; the success of an application depends on the properties of the membranes selected for its realization. For the first time, the results of a comprehensive characterization of the transport properties of IEMs from three manufactures (Astom, Japan; Shchekinoazot, Russia; and Fujifilm, The Netherlands) are reported. Our own and literature data are presented and analyzed using the microheterogeneous model. Homogeneous Neosepta AMX and CMX (Astom), heterogeneous MA-41 and MK-40 (Shchekinoazot), and AEM Type-I, AEM Type-II, AEM Type-X, as well as CEM Type-I, CEM Type-II, and CEM Type-X produced by the electrospinning method (Fujifim) were studied. The concentration dependencies of the conductivity, diffusion permeability, as well as the real and apparent ion transport numbers in these membranes were measured. The counterion transport number characterizing the membrane permselectivity increases in the following order: CEM Type-I MA-41 < AEM Type-I < MK-40<CMX CEM Type-II CEM Type-X AEM Type-II < AMX < AEM Type-X. It is shown that the properties of the AEM Type-I and CEM Type-I membranes are close to those of the heterogeneous MA-41 and MK-40 membranes, while the properties of Fujifilm Type-II and Type-X membranes are close to those of the homogeneous AMX and CMX membranes. This difference is related to the fact that the Type-I membranes have a relatively high parameter f2, the volume fraction of the electroneutral solution filling the intergel spaces. This high value is apparently due to the open-ended pores, formed by the reinforcing fabric filaments of the Type-I membranes, which protrude above the surface of these membranes.

scholarly journals Temperature dependent radiative and non-radiative recombination dynamics in CdSe–CdTe and CdTe–CdSe type II hetero nanoplatelets

2016 ◽  
Vol 18 (4) ◽  
pp. 3197-3203 ◽  
Author(s):  
Riccardo Scott ◽  
Sebastian Kickhöfel ◽  
Oliver Schoeps ◽  
Artsiom Antanovich ◽  
Anatol Prudnikau ◽  
...  
Keyword(s):  
Temperature Dependence ◽  
Radiative Recombination ◽  
Type Ii ◽  
Temperature Dependent ◽  
Radiative Lifetimes ◽  
First Time ◽  
Recombination Dynamics

We reveal for the first time the temperature dependence of the radiative and non-radiative lifetimes of type II excitons in hetero nanoplatelets.

Sign in / Sign up

Export Citation Format

Share Document