Annealing Treatment Effect on Photoelectric Properties of P3HT:PCBMBlend System

Nanostructural WO3 materials exhibit excellent gasochormism performance under the action of the hydrogen gas. In this paper, we study the mechanism of annealing treatment effect on the gasochromic properties both of the WO3 bulks and WO3 films. WO3 bulks were prepared from WO3 sol and dried under ambient pressure, which was previously synthesized via sol-gel method. The WO3 films were prepared using dip-coating method. UV-visible spectroscopy, Raman spectroscopy, Fourier transforms infrared spectroscopy (FT-IR) and X-ray diffraction spectra (XRD) were utilized to investigate components, structures and gasochromic properties. And we find that the mechanism of the thermal treatment on the gasochromic performance depends on H+ diffusion velocity which largely relies on the structural water content.

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HEAT TREATMENT EFFECT ON MARAGING STEEL MANUFACTURED BY LASER POWDER BED FUSION TECHNOLOGY: MICROSTRUCTURE AND MECHANICAL PROPERTIES

Acta Metallurgica Slovaca ◽

10.36547/ams.27.3.973 ◽

2021 ◽

Vol 27 (3) ◽

pp. 122-126

Author(s):

Giulia Stornelli ◽

Damiano Gaggia ◽

Marco Rallini ◽

Andrea Di Schino

Keyword(s):

Heat Treatment ◽

Maraging Steel ◽

Treatment Effect ◽

Annealing Treatment ◽

Ageing Temperature ◽

Powder Bed Fusion ◽

Solution Annealing ◽

Laser Powder Bed Fusion ◽

Powder Bed ◽

Hardening Treatment

Laser Powder Bed Fusion (L-PBF) is a widespread additive manufacturing technology in industrial applications, for metal components manufacturing. Maraging steel is a special class of Fe-Ni alloys, typically used in the aerospace and tooling sectors due to their good combination of mechanical strength and toughness. This work analyses the heat treatment effect on the microstructure and hardness value of 300-grade maraging steel manufactured by the L-PBF process. The considered heat treatment consists of a solution annealing treatment followed by quenching and ageing hardening treatment. The effect of ageing temperature is reported, in a wide temperature range. Results show that solution annealing treatment fully dissolves the solidification structure caused by the L-PBF process. Moreover, the ageing hardening treatment has a significant impact on the hardness, hence on strength, of L-PBF maraging steel. The optimal ageing conditions for the L-PBF maraging steel are identified and reported: in particular, results show that the hardness of 583 HV is achieved following ageing treatment at 490 °C for 6 hours. A higher treatment temperature leads to over-ageing resulting in a decrease of hardness. Conversely, an excessive ageing time does not seem to affect the hardness value, for the ageing temperature of 490 °C.

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Effect of Annealing Atmosphere on Structure and Properties in Chemically Deposited PbS Thin Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.399-401.875 ◽

2011 ◽

Vol 399-401 ◽

pp. 875-879

Author(s):

Feng Liu ◽

Hong Deng ◽

Ai Ping Zhao ◽

Xue Ran Deng

Keyword(s):

Thin Films ◽

Surface Defects ◽

Test Chamber ◽

Chemical Deposition ◽

Annealing Treatment ◽

Test Methods ◽

Annealing Atmosphere ◽

Large Area ◽

Photoelectric Properties ◽

The Stability

Large area (13mm*13mm) PbS thin films with (200) preferred orientation were prepared by chemical deposition. The optical properties of PbS films with annealing treatment in various forming gases with different ratio of nitrogen-oxygen (100ml/min of N2&O2(3:1), 100ml/min of N2&O2(2:1), 100ml/min of N2&O2(1:1), 50ml/min of O2) were deeply analyzed. X-ray diffraction (XRD), scanning electron microscope (SEM), high and low temperature test chamber and other test methods for photosensitivity were used to investigate the structure and photoelectric properties of PbS films. The results showed that with proper amount of oxidation (when nitrogen-oxygen ratio was 1:1), the impurity barrier tended to fully grow, impurity activation energy increased to 0.314eV, dark resistance reached up to 30.2MΩ, and the photoconductive sensitivity of PbS thin film under this process was about 4 times larger compared with air annealing. According to the analysis of XRD patterns and surface morphologies of films, it can be seen that nitrogen in this process was not only to prevent PbS thin films from excessive oxidation, but also inhibited the formation of surface defects and enhanced the stability of PbS device.

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Morphological transformations in solution-cast Styrene-Butadiene-Styrene (SBS) triblock copolymer thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010013729x ◽

1995 ◽

Vol 53 ◽

pp. 184-185

Author(s):

Ginam Kim ◽

W. Marsillo ◽

M. Libera

Keyword(s):

Thin Films ◽

Triblock Copolymer ◽

Annealing Treatment ◽

Minor Component ◽

Solvent Evaporation ◽

Single Crystal Substrate ◽

Transparent Films ◽

Crystal Substrate ◽

Solution Cast ◽

Morphological Transformations

The fact that block copolymers can assume a range of morphologies depending upon such variables as relative block length and molecular weight is now well known. In the case of poly(styrene)[PS]-poly(butadiene)[PB]-poly(styrene) (SBS) triblock copolymer, the morphologies range from spheres (roughly ~20% minor component), to cylinders (roughly 20%~35% minor component), to lamellae (roughly equal component fractions) Most recently, there has been increasing interest in transformations between morphologies by thermal annealing. This paper describes initial results studying the effect of solvent evaporation rate and post-casting annealing treatment on the morphology of SBS thin films.TEM specimens were prepared by solution casting electron transparent films. 50 μl of 0.1 wt% SBS (30% styrene, Mw=14,000, Scientific Polymer Products, Inc.) dissolved in toluene was deposited on a polished NaCl single crystal substrate placed in a small dish. After solvent evaporation the film was cut into small squares, floated from the salt in water, and each square was collected on a Cu grid.

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The microstructure change of low-carbon electrical steels by residual aluminum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153403 ◽

1989 ◽

Vol 47 ◽

pp. 286-287

Author(s):

C.K. Hou ◽

C.T. Hu ◽

Sanboh Lee

Keyword(s):

Annealing Treatment ◽

Low Carbon ◽

Electrical Steels ◽

Vacuum Degassing ◽

Spherical Inclusions ◽

Residual Aluminum ◽

Average Grain Size ◽

The Matrix ◽

Fine Size ◽

To Come

The fully processed low-carbon electrical steels are generally fabricated through vacuum degassing to reduce the carbon level and to avoid the need for any further decarburization annealing treatment. This investigation was conducted on eighteen heats of such steels with aluminum content ranging from 0.001% to 0.011% which was believed to come from the addition of ferroalloys.The sizes of all the observed grains are less than 24 μm, and gradually decrease as the content of aluminum is increased from 0.001% to 0.007%. For steels with residual aluminum greater than 0. 007%, the average grain size becomes constant and is about 8.8 μm as shown in Fig. 1. When the aluminum is increased, the observed grains are changed from the uniformly coarse and equiaxial shape to the fine size in the region near surfaces and the elongated shape in the central region. SEM and EDAX analysis of large spherical inclusions in the matrix indicate that silicate is the majority compound when the aluminum propotion is less than 0.003%, then the content of aluminum in compound inclusion increases with that in steel.

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Characterisation of planar crystal defects in Y2Fe17Cx (0.6 ≤ x ≤ 1.6) magnetic material by High Resolution Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100177003 ◽

1990 ◽

Vol 48 (4) ◽

pp. 774-775

Author(s):

W. Coene ◽

F. Hakkens ◽

T.H. Jacobs ◽

K.H.J. Buschow

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Permanent Magnets ◽

Annealing Treatment ◽

High Resolution Electron Microscopy ◽

Crystal Defects ◽

Ordered Structure ◽

X Ray ◽

Planar Crystal ◽

Resolution Electron

Intermetallic compounds of the type RE2Fe17Cx (RE= rare earth element) are promising candidates for permanent magnets. In case of Y2Fe17Cx, the Curie temperature increases from 325 K for x =0 to 550 K for x = 1.6 . X ray and electron diffraction reveal a carbon - induced structural transformation in Y2Fe17Cx from the hexagonal Th2Ni17 - type (x < 0.6 ) to the rhombohedral Th2Zn17 - type ( x ≥ 0.6). Planar crystal defects introduce local sheets of different magnetic anisotropy as compared with the ordered structure, and therefore may have an important impact on the coercivivity mechanism .High resolution electron microscopy ( HREM ) on a Philips CM30 / Super Twin has been used to characterize planar crystal defects in rhombohedral Y2Fe17Cx ( x ≥ 0.6 ). The basal plane stacking sequences are imaged in the [100] - orientation, showing an ABC or ACB sequence of Y - atoms and Fe2 - dumbbells, for both coaxial twin variants, respectively . Compounds resulting from a 3 - week annealing treatment at high temperature ( Ta = 1000 - 1100°C ) contain a high density of planar defects.

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TEM study of buried cobalt disilicide layers formed by ion implantation: Identification of cobalt monosilicide inclusions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176010 ◽

1990 ◽

Vol 48 (4) ◽

pp. 576-577

Author(s):

A. De Veirman ◽

J. Van Landuyt ◽

K.J. Reeson ◽

R. Gwilliam ◽

C. Jeynes ◽

...

Keyword(s):

Ion Implantation ◽

Annealing Treatment ◽

Silicon On Insulator ◽

High Dose ◽

Nitrogen Flow ◽

Cobalt Disilicide ◽

Transmission Electron ◽

Beam Heating ◽

Co Concentration ◽

Silicon On Insulator Technology

In analogy to the formation of SIMOX (Separation by IMplanted OXygen) material which is presently the most promising silicon-on-insulator technology, high-dose ion implantation of cobalt in silicon is used to synthesise buried CoSi2 layers. So far, for high-dose ion implantation of Co in Si, only formation of CoSi2 is reported. In this paper it will be shown that CoSi inclusions occur when the stoichiometric Co concentration is exceeded at the peak of the Co distribution. 350 keV Co+ ions are implanted into (001) Si wafers to doses of 2, 4 and 7×l017 per cm2. During the implantation the wafer is kept at ≈ 550°C, using beam heating. The subsequent annealing treatment was performed in a conventional nitrogen flow furnace at 1000°C for 5 to 30 minutes (FA) or in a dual graphite strip annealer where isochronal 5s anneals at temperatures between 800°C and 1200°C (RTA) were performed. The implanted samples have been studied by means of Rutherford Backscattering Spectroscopy (RBS) and cross-section Transmission Electron Microscopy (XTEM).

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The Effect of Partly Missing Covariates on Statistical Power in Randomized Controlled Trials With Discrete-Time Survival Endpoints

Methodology ◽

10.1027/1614-2241/a000121 ◽

2017 ◽

Vol 13 (2) ◽

pp. 41-60

Author(s):

Shahab Jolani ◽

Maryam Safarkhani

Keyword(s):

Randomized Controlled Trials ◽

Discrete Time ◽

Treatment Effect ◽

Survival Data ◽

Controlled Trials ◽

Missing Covariates ◽

Indicator Method ◽

Imputation Methods ◽

Randomized Controlled ◽

Baseline Covariates

Abstract. In randomized controlled trials (RCTs), a common strategy to increase power to detect a treatment effect is adjustment for baseline covariates. However, adjustment with partly missing covariates, where complete cases are only used, is inefficient. We consider different alternatives in trials with discrete-time survival data, where subjects are measured in discrete-time intervals while they may experience an event at any point in time. The results of a Monte Carlo simulation study, as well as a case study of randomized trials in smokers with attention deficit hyperactivity disorder (ADHD), indicated that single and multiple imputation methods outperform the other methods and increase precision in estimating the treatment effect. Missing indicator method, which uses a dummy variable in the statistical model to indicate whether the value for that variable is missing and sets the same value to all missing values, is comparable to imputation methods. Nevertheless, the power level to detect the treatment effect based on missing indicator method is marginally lower than the imputation methods, particularly when the missingness depends on the outcome. In conclusion, it appears that imputation of partly missing (baseline) covariates should be preferred in the analysis of discrete-time survival data.

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NIDA CTN Treatment Effect and Assessment Measures Task Force Recommendations

PsycEXTRA Dataset ◽

10.1037/e632372012-001 ◽

2012 ◽

Author(s):

John G. Gardin

Keyword(s):

Treatment Effect ◽

Task Force ◽

Assessment Measures

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