The Human Connectome Project (HCP) has developed protocols, standard operating and quality control procedures, and a suite of informatics tools to enable high throughput data collection, data sharing, automated data processing and analysis, and data mining and visualization. Quality control procedures include methods to maintain data collection consistency over time, to measure head motion, and to establish quantitative modality-specific overall quality assessments. Database services developed as customizations of the XNAT imaging informatics platform support both internal daily operations and open access data sharing. The Connectome Workbench visualization environment enables user interaction with HCP data and is increasingly integrated with the HCP's database services. Here we describe the current state of these procedures and tools and their application in the ongoing HCP study.
Polyfuran films have been synthesized by electropolymerization of terfuran and investigated as a function of film preparation conditions in both the doped and undoped state. These films have been characterized by infrared spectroscopy, scanning electron microscopy, optical absorption, X-ray photoelectron spectroscopy, dc conductivity, and electron spin resonance measurements. The electrolyte anion (dopant) used for the preparation of these films heavily influences the -conjugated system of the polymer backbone. Structural disorder and doping level depends on the nature of the electrolyte anion. CF3SO3-was found to be the best dopant and to cause the least structural disorder or furan ring opening. Electrical conductivities as high as 2 X 10-3 S/cm were obtained in the CFsSOs'-doped state. The temperature dependence of the electrical conductivity indicates a thermally activated process with semiconductorlike behavior. The charge transport properties are explained in terms of polaron and bipolaron states. The polymer band gap was measured at 2.35 eV.
Equilibrium phase relationships in the ZnO-In 2 O 3 system were determined between 1100°and 1400°C using solidstate reaction techniques and X-ray diffractometry. In addition to ZnO and In 2 O 3 , nine homologous compounds, Zn k In 2 O k+3 (where k = 3, 4, 5, 6, 7, 9, 11, 13, and 15), were observed. Electrical conductivity and diffuse reflectance of the k = 3, 4, 5, 7 and 11 members were measured before and after annealing at 400°C for 1 h under forming gas (4% H 2 -96% N 2 ). Room-temperature conductivity increased as k decreased, because of increased carrier concentration as well as increased mobility. In general, transparency in the wavelength range of 450-900 nm increased as k increased. Reduction in forming gas resulted in increased conductivity and reduced transparency for all compounds measured. The highest room-temperature conductivity measured, 270 S/cm, was that of reduced Zn 3 In 2 O 6 .
Polyaniline can be inserted in
V2O5·nH2O xerogel by
in situ oxidative polymerization/intercalation of aniline or anilinium in air. The reaction is
facile and topotactic, forming
polyaniline as the emeraldine salt. The interlayer separation (5.6
Å) is consistent with a
monolayer of polymer chains in the V2O5
framework. Evidence is presented that oxygen
acts as an electron acceptor both during the in situ reaction and long
after intercalation is
complete. The crucial role of oxygen in this reaction is probed
and discussed. In an
alternative route, anilinium is first intercalated and then, in a
second step, is oxidatively
polymerized in the xerogel upon exposure of the intercalate sample to
air. Upon standing
in air (aging), two processes occur independently in these materials:
(a) the partial
reoxidation of the reduced V2O5 framework and
(b) further oxidative coupling of anilinium
and aniline oligomers inside the V2O5 layers,
leading to longer chain molecules. These
observations are supported by several physicochemical data. The
magnetic moment of
(PANI)
x
V2O5·nH2O
decreases gradually upon exposure to air, but it does not change
when
the sample is stored in vacuum. Gel permeation chromatography
(GPC) analysis results
show that the molecular weight of polyaniline extracted from aged
(PANI)
x
V2O5·nH2O
is
larger than that extracted from the fresh samples. The thermal
stability of polyaniline
extracted from aged
(PANI)
x
V2O5·nH2O
is better than that extracted from fresh samples.
All
(PANI)
x
V2O5·nH2O
samples are paramagnetic with a Curie−Weiss and a
temperature-independent van Vleck contribution. Variable-temperature
2H-wide-line NMR of
(PANI)
x
V2O5·nH2O shows that
the polymer chains are sterically confined with respect to
phenyl
ring rotation. The room-temperature conductivity of the freshly
prepared
(PANI)
x
V2O5·nH2O
samples is in the range
10-4−10-1 S/cm
depending on the degree of polymerization inside
the layers, but the conductivity of aged samples is always greater.
Room temperature
thermoelectric power is negative and varies (−30 to 200 μV/K)
depending on the polymer
content and the degree of polymerization.
A
modified method for obtaining large quantities of exfoliated single
layers of WS2 is reported. The restacked
WS2 obtained from the precipitation of the single layers is
metastable with respect to 2H-WS2 with an apparent
activation energy of 82.4 kJ/mol, and a conversion temperature of 207
°C at 5 °C/min. Pressed pellets of restacked WS2
have electrical conductivity of ∼7 S/cm. The material exhibits
Pauli paramagnetism.
were synthesized by a molten flux method. The black needles of compound I were formed at 600°C and crystallized in the monoclinic P2 1 /m space group (No. 11) with a ) 17.492(3) Å, b ) 4.205(1) Å, c ) 18.461(4) Å, ) 90.49(2)°. The final R/R w ) 6.7/5.7%. Compound II is isostructural to I. Both I and II are isostructural with K 2 Bi 8 S 13 which is composed of NaCl-, Bi 2 Te 3 -, and CdI 2 -type units connecting to form K + -filled channels. The thin black needles of III and IV obtained at 530°C crystallize in the same space group P2 1 /m with a ) 17.534 (4) Å, b ) 4.206(1) Å, c ) 21.387(5) Å, ) 109.65(2)°and a ) 17.265(3) Å, b ) 4.0801(9) Å, c ) 21.280(3) Å, ) 109.31 (1)°, respectively. The final R/R w ) 6.3/8.3% and 5.1/3.6%. Compounds III and IV are isostructural and potassium and bismuth/antimony atoms are disordered over two crystallographic sites. The structure type is very closely related to that of I. Electrical conductivity and thermopower measurements show semiconductor behavior with ∼250 S/cm and ∼-200 µV/K for a single crystal of I and ∼150 S/cm and ∼-100 µV/K for a polycrystalline ingot of III at room temperature. The effect of vaccum annealing on these compounds is explored. The optical bandgaps of all compounds were determined to be 0.59, 0.78, 0.56, and 0.82 eV, respectively. The thermal conductivities of melt-grown polycrystalline ingots of I and III are reported.
A general approach for the encapsulation of a variety of saturated polymers between the layers of MoS2 giving electrically conductive lamellar compounds is reported.
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