Dehydration of rhyolite: activation energy, water speciation and morphological investigation

AbstractDue to the high temperatures used for high deposition rate microcrystalline (μc-Si:H) and polycrystalline silicon, there is a need for compact and temperature-stable doped layers. In this study we report on films grown by the layer-by-layer method (LbL) using VHF PECVD. Growth of an amorphous silicon layer is alternated by a hydrogen plasma treatment. In LbL, the surface reactions are separated time-wise from the nucleation in the bulk. We observed that it is possible to incorporate dopant atoms in the layer, without disturbing the nucleation. Even at high substrate temperatures (up to 400°C) doped layers can be made microcrystalline. At these temperatures, in the continuous wave case, crystallinity is hindered, which is generally attributed to the out-diffusion of hydrogen from the surface and the presence of impurities (dopants).We observe that the parameter window for the treatment time for p-layers is smaller compared to n-layers. Moreover we observe that for high temperatures, the nucleation of p-layers is more adversely affected than for n-layers. Thin, doped layers have been structurally, optically and electrically characterized. The best n-layer made at 400°C, with a thickness of only 31 nm, had an activation energy of 0.056 eV and a dark conductivity of 2.7 S/cm, while the best p-layer made at 350°C, with a thickness of 29 nm, had an activation energy of 0.11 V and a dark conductivity of 0.1 S/cm. The suitability of these high temperature n-layers has been demonstrated in an n-i-p microcrystalline silicon solar cell with an unoptimized μc-Si:H i-layer deposited at 250°C and without buffer. The Voc of the cell is 0.48 V and the fill factor is 70 %.

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Features hormonal hemostasis in patients with benign hyper-plastic processes of breasts

HEALTH OF WOMAN ◽

10.15574/hw.2016.115.72 ◽

2016 ◽

pp. 72-74 ◽

Cited By ~ 2

Author(s):

M. Makarenko ◽

◽

D. Govsieiev ◽

O. Gromova ◽

L. Martynova ◽

...

Keyword(s):

Luteal Phase ◽

Reproductive Organs ◽

Breast Diseases ◽

Hormonal Changes ◽

Morphological Investigation ◽

Fibrocystic Disease ◽

X Ray ◽

Pelvic Organs ◽

Hormone Research ◽

Gynecological Diseases

The objective: to study the incidence of gynecological diseases, clinical and hormonal parameters of the menstrual cycle in patients with benign hyper-plastic processes of breasts. Patients and methods. 65 women with various forms of mastitis were investigated. The following investigations were conducted: mammologistic and gynecological investigation, mommologistic X-ray investigation, ultrasound of breasts and of the pelvic organs, endometrial aspiration biopsy that was followed by cytology; when it was necessary the diagnostic laparoscopy, colposcopy, hysteroscope with curettage and morphological investigation of the endometrium, hormone research and rectal temperature measurements were conducted. Results. The frequency of the benign breast diseases was set: fibrocystic disease of breast – 32 women (49.2±6.20%), fibrous of breast – 16 women (24.6±5.34%), nodular of breasts – 8 women (12.3±4.07%), fibroadenoma – 6 women (9.2±3.59%), nodular disease of breasts on the background of fibroid changes – 3 women (4.6±2.60%). All in all, 96.9±2.14% of the patients had any gynecological diseases. Thus, the average age of the ‘debut’ of mastitis was 31.4±1.09 years; the hyper-plastic processes in the uterus was 35.2±1.17 years. Anovulation was detected in 17 (47.2±8.3%) patients, the lack of the luteal phase (NLF) was detected in 11 (30.6±7.6) patients. Conclusions. Identified hormonal changes are typical for patients with the hyper-plastic processes of the reproductive organs with different localization (breasts, uterus, ovaries). Due to the commonality of the hormone changes in most cases mastitis is combined with the various gynecological diseases (96.9±2.14%). Key words: gynecological pathology, hormonal changes, breast, factors of risk.

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Systematics of Hymenophyllum subgenus Mecodium (Hymenophyllaceae) in Taiwan

Systematic Botany ◽

10.1600/036364419x15710776741413 ◽

2019 ◽

Vol 44 (4) ◽

pp. 753-767

Author(s):

Tian-Chuan Hsu ◽

Yu-Fang Huang ◽

Yi-Shan Chao

Keyword(s):

Phylogenetic Relationships ◽

The Philippines ◽

Common Element ◽

Morphological Investigation ◽

Eastern Asia ◽

Type Specimens ◽

The Status ◽

Molecular Phylogenetic ◽

A New Species ◽

Independent Species

Abstract—Hymenophyllum subg. Mecodium, composed of the taxonomically notorious H. polyanthos and approximately 15 other closely related taxa, is a common element of filmy fern communities in the tropical and subtropical moist forests. In Taiwan, although only H. polyanthos and one or two closely related taxa were recognized in recent studies, considerable morphological variation has been observed among populations throughout the island. Thus, we conducted an extensive morphological investigation, as well as a molecular phylogenetic analysis, to clarify the specific diversity and phylogenetic relationships within Hymenophyllum subg. Mecodium in Taiwan. Field and herbaria surveys helped in recognizing five morphs in Taiwan, mainly differentiated by the combination of certain traits, viz., the presence or absence of stipe wings, general frond size and shape, degree of laminar crispation, sori position, and involucre shape. The different morphs had diverse ecological preferences. The phylogenetic tree, inferred from the sequences of the plastid loci rbcL and rps4-trnS, demonstrated that Hymenophyllum subg. Mecodium materials in Taiwan comprise several well-supported lineages, mostly corresponding to the classification based on morphology. Comparing with the protologues and type specimens of 34 related scientific names, the five morphs are herein recognized as five independent species. A new species, Hymenophyllum exquisitum, is described here. Also, the status of H. paniculiflorum is reconfirmed and that of H. fujisanense, H. parallelocarpum, and H. punctisorum reinstated. Only H. exquisitum and H. parallelocarpum are endemic to Taiwan among all the species studied. In addition, the names Hymenophyllum blumeanum, H. integrum, H. microsorum, H. polyanthos, H. tenellum, and H. wrightii are now excluded from the regional flora, and several related taxa from China, Taiwan, and the Philippines are treated as synonyms. This study unravels the deep phylogenetic relationships within Hymenophyllum subg. Mecodium in Taiwan and Eastern Asia.

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White- and Brown-Rice Supplementation Improves Insulin Tolerance, Brown Fat Activation, Energy Expenditure, and Changes the Gut Microflora in Diet-Induced Obesity

Diabetes ◽

10.2337/db18-1897-p ◽

2018 ◽

Vol 67 (Supplement 1) ◽

pp. 1897-P

Author(s):

HISASHI YOKOMIZO ◽

ATSUSHI ISHIKADO ◽

TAKANORI SHINJO ◽

KYOUNGMIN PARK ◽

YASUTAKA MAEDA ◽

...

Keyword(s):

Activation Energy ◽

Energy Expenditure ◽

Brown Rice ◽

Brown Fat ◽

Gut Microflora ◽

Diet Induced Obesity ◽

Insulin Tolerance

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Activation energy of relaxation processes in chalcogenide glasses

Scientific Herald of Uzhhorod University Series Physics ◽

10.24144/2415-8038.2013.34.59-63 ◽

2013 ◽

Vol 34 (0) ◽

pp. 59-63

Author(s):

А. А. Горват ◽

В. М. Кришеник ◽

А. Е. Кріштофорій ◽

В. В. Мінькович ◽

О. А. Молнар

Keyword(s):

Activation Energy ◽

Chalcogenide Glasses ◽

Relaxation Processes

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Dielectric Relaxation Studies of Silver Nanoparticles dispersed Liquid Crystal

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v8i3.1496 ◽

2015 ◽

Vol 8 (3) ◽

pp. 2176-2188 ◽

Cited By ~ 4

Author(s):

Keisham Nanao Singh

Keyword(s):

Activation Energy ◽

Silver Nanoparticles ◽

Liquid Crystal ◽

Dielectric Relaxation ◽

Relaxation Process ◽

Relaxation Times ◽

Low Frequency ◽

Bulk Liquid ◽

Molecular Rearrangement ◽

Relaxation Studies

This article reports on the Dielectric Relaxation Studies of two Liquid Crystalline compounds - 7O.4 and 7O.6 - doped with dodecanethiol capped Silver Nanoparticles. The liquid crystal molecules are aligned homeotropically using CTAB. The low frequency relaxation process occurring above 1 MHz is fitted to Cole-Cole formula using the software Dielectric Spectra fit. The effect of the Silver Nanoparticles on the molecular dipole dynamics are discussed in terms of the fitted relaxation times, Cole-Cole distribution parameter and activation energy. The study indicate a local molecular rearrangement of the liquid crystal molecules without affecting the order of the bulk liquid crystal molecules but these local molecules surrounding the Silver Nanoparticles do not contribute to the relaxation process in the studied frequency range. The observed effect on activation energy suggests a change in interaction between the nanoparticles/liquid crystal molecules.

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Pt-Pd Nanoalloy for the Unprecedented Activation of Carbon-Fluorine Bond at Low Temperature

10.26434/chemrxiv.11145098 ◽

2019 ◽

Author(s):

Raghu Nath Dhital ◽

keigo nomura ◽

Yoshinori Sato ◽

Setsiri Haesuwannakij ◽

Masahiro Ehara ◽

...

Keyword(s):

Activation Energy ◽

Low Temperature ◽

Dft Calculations ◽

Bond Activation ◽

Mild Conditions ◽

Selective Transformation ◽

Rate Determining Step ◽

Highly Active ◽

Harsh Conditions ◽

Reaction Profile

Carbon-Fluorine (C-F) bonds are considered the most inert organic functionality and their selective transformation under mild conditions remains challenging. Herein, we report a highly active Pt-Pd nanoalloy as a robust catalyst for the transformation of C-F bonds into C-H bonds at low temperature, a reaction that often required harsh conditions. The alloying of Pt with Pd is crucial to activate C-F bond. The reaction profile kinetics revealed that the major source of hydrogen in the defluorinated product is the alcoholic proton of 2-propanol, and the rate-determining step is the reduction of the metal upon transfer of the <i>beta</i>-H from 2-propanol. DFT calculations elucidated that the key step is the selective oxidative addition of the O-H bond of 2-propanol to a Pd center prior to C-F bond activation at a Pt site, which crucially reduces the activation energy of the C-F bond. Therefore, both Pt and Pd work independently but synergistically to promote the overall reaction

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