Hexagonal platy halloysite in an altered tuff bed, Komaki City, Aichi Prefecture, Central Japan

Clay Minerals ◽  
1986 ◽  
Vol 21 (3) ◽  
pp. 401-415 ◽  
Author(s):  
H. Noro
Keyword(s):  
Volcanic Glass ◽  
Xrd Analysis ◽  
Natural State ◽  
Curvature Radius ◽  
Central Japan ◽  
Octahedral Sheet ◽  
Aichi Prefecture ◽  
Increase With Increase ◽  
The Stability ◽  
Main Component

AbstractXRD analysis and electron microscopy show that hexagonal platy halloysite is the main component of an altered tuff (Ueno tuff bed) in the Pliocene Seto group, Aichi Prefecture, Central Japan. In the natural state it shows a single basal peak at 10·1 Å, which collapses to 7·2 Å, by dehydration through a segregate-type interstratification. The (02,11) non-basal band consists of slightly separated peaks which indicates moderate ordering of the crystal structure. The b-dimension is 8·936–8·939 Å. The stability of the interlayer water is intermediate with respect to halloysites of different morphologies. Between 3·5 and 4% Fe2O3 is present in the deferrated sample and the calculated chemical formula can not explain the anomalously high CEC of 21·9 mEq/100 g. Because the curvature radius and b-dimension of halloysite increase with increase in Fe2O3 content, the platy morphology is ascribed to replacement of Al3+ by Fe3+ in the octahedral sheet. Based on the geological and chemical data, the hexagonal platy halloysite is considered to have been formed from volcanic glass after deposition in a freshwater lake, where conditions were oxidizing and weakly acidic.

Foods and Nutrients in Relation to Bladder Cancer Risk: A Case-Control Study in Aichi Prefecture, Central Japan

2000 ◽  
Vol 38 (1) ◽  
pp. 13-22 ◽  
Author(s):  
Kenji Wakai ◽  
Munehisa Takashi ◽  
Kikuo Okamura ◽  
Hiroshi Yuba ◽  
Koh-ichi Suzuki ◽  
...  
Keyword(s):  
Bladder Cancer ◽  
Cancer Risk ◽  
Case Control Study ◽  
Case Control ◽  
Bladder Cancer Risk ◽  
Central Japan ◽  
Aichi Prefecture ◽  
Control Study

scholarly journals COMPARISON OF DYNAMIC STABILITY DURING WALKING AND RUNNING ON NONMOTORIZED CURVED TREADMILL ACCORDING TO CURVATURE RADIUS

2017 ◽  
Vol 17 (08) ◽  
pp. 1750105
Author(s):  
SAYUP KIM ◽  
JONGRYUN ROH ◽  
JOONHO HYEONG ◽  
YOUNGHO KIM
Keyword(s):  
Dynamic Stability ◽  
Repeated Measures ◽  
The Elderly ◽  
Curvature Radius ◽  
Adult Men ◽  
High Speeds ◽  
Slow Walking ◽  
Study Results ◽  
The Stability ◽  
Post Hoc

It is generally believed that running on a curved surface is more unstable than running on a flat surface. In this study, the dynamic stability of locomotion on a nonmotorized curved treadmill (NMCT) with three curvature radii was compared with that on a motorized flat treadmill. Sixteen healthy adult men maintained four different self-paced speeds: slow walking, fast walking, jogging, and running. Significant differences were statistically verified using two-way repeated-measures analysis of variance (ANOVA) according to the curvature radii and speeds, and the interaction effects were confirmed. Furthermore, to understand the significant differences between the speed and curvature radius, post hoc analyses were performed using one-way ANOVA. Except for the step width, the other parameters showed differences and correlation effects between the curvature radius and speed. As the curvature radius decreased, the stability decreased at slow speeds (slow walking) but increased at fast speeds (running). However, as the curvature radius increased, the stability increased at slow speeds (slow walking) but decreased at high speeds (running). The study results will help in suggesting the appropriate curvature radius for different user types such as athletes, the elderly, and people who require rehabilitation and will serve as preliminary data for designing the curvature radii of NMCTs.

scholarly journals Review on Lateral Stability of Piled Riverine Structures in the Estuaries of Sarawak

2018 ◽  
Vol 7 (3.18) ◽  
pp. 21
Author(s):  
Lee Lin Jye ◽  
Shenbaga R. Kaniraj ◽  
Siti Noor Linda bt Taib ◽  
Fauzan Bin Sahdi
Keyword(s):  
Soft Soil ◽  
Natural State ◽  
Soil Conditions ◽  
Silty Clay ◽  
River Bank ◽  
Soil Movement ◽  
Geotechnical Problem ◽  
Construction Activity ◽  
Lateral Soil Movement ◽  
The Stability

Soft soil conditions with very soft and deep silty clay have constantly endangered the stability of the riverine and estuarine structures in Sarawak. There have been many failures of jetties, wharves and bridges in Sarawak. In many cases of failures, the piles were not designed to resist the lateral movement, unless they were included to stabilize unstable slopes or potential landslides. This practice may be due to reasons such as erroneously judging the river bank as stable in slope stability analysis or simply due to the inexperience of designers. Also, when the river bank approaches the limiting stability in its natural state any construction activity on the river bank could result in lateral soil movement. This paper highlights this important geotechnical problem in Sarawak. Then it presents the details of a few failures of estuarine structures. A review of situations causing lateral loading of piles is then presented. The results of the in-soil and in-pile displacement measurements are shown in this paper and it is found that the computation made to compare between field and 3D modeling is agreeable.  

COMPOSITION OF MATTER IN NUCLEAR STATISTICAL EQUILIBRIUM AT HIGH DENSITIES

1965 ◽  
Vol 43 (11) ◽  
pp. 2056-2077 ◽  
Author(s):  
Sachiko Tsuruta ◽  
A. G. W. Cameron
Keyword(s):  
Dense Matter ◽  
Closed Shell ◽  
Neutrino Energy ◽  
Statistical Equilibrium ◽  
Stable Region ◽  
General Tendency ◽  
Increase With Increase ◽  
Pure Helium ◽  
The Stability ◽  
Increasing Temperature

Various properties of dense matter in nuclear statistical equilibrium are studied for densities and temperatures in the range [Formula: see text] and [Formula: see text]. With increasing density the stability shifts to more and more neutron-rich nuclei. With increasing temperature the general tendency is that nuclei of smaller charge become more abundant, and the abundances of nuclei near a peak tend to become nearly as large as that of the peak nucleus. The shifting of the most stable region with change of density or temperature takes place rather abruptly from one neutron closed shell region to the next. For densities [Formula: see text], the ordinary iron group nuclei are most stable until the temperature becomes about 5 × 109 °K; for higher temperatures matter in equilibrium consists of almost pure helium. For higher density, this transition to a helium phase takes place at a somewhat higher temperature, and the equilibrium configuration for temperatures below the helium transition point shifts to the neutron-rich side of the valley of beta stability. When [Formula: see text], matter consists of almost pure neutrons at all densities. Rates of beta reactions and neutrino emission generally increase with increase of density and temperature. At a typical temperature of about 5 × 109 °K, the neutrino energy emission rate increases from about 2 × 1011 ergs/g sec at ρ ~ 106 g/cm3 to about 2 × 1017 erg/g sec at ρ ~ 3 × 1011 g/cm3.

scholarly journals Improved Biodegradable Radiation Cured Polymeric Film Prepared from Chitosan-Gelatin Blend

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Zinia Nasreen ◽  
Mubarak A. Khan ◽  
A. I. Mustafa
Keyword(s):  
Thin Films ◽  
Fourier Transform ◽  
Soil Degradation ◽  
Structural Changes ◽  
Xrd Analysis ◽  
Gamma Dose ◽  
Ftir Studies ◽  
The Stability ◽  
Degradation Properties ◽  
Scanning Electron

The mechanical, thermal, swelling, and release properties of chitosan-gelatin (CG) films have been investigated in order to verify the influence of UV and gamma radiation on the stability of the films. Thin films of chitosan and gelatin (1 : 3, w/w) that were radiated with 100 krad of gamma dose showed the best performance and the TS values reached 25, 45, and 49 MPa, respectively, for chitosan, gelatin, and blend. The corresponding highest TS values were 23, 42, and 45 MPa, respectively, for 10 passes of UV radiation. The effect of radiation over gelatin, chitosan, and CG blend caused modification in the arrangement of molecules in the crystal lattice that is significant by XRD analysis. Surfaces of the films were also investigated by scanning electron microscope (SEM). Fourier transform infrared spectroscopy (FTIR) studies further revealed structural changes of the films. These changes were attributed to understanding the behavior of the irradiated chitosan, gelatin, and CG blend on application of thermal energy using DSC and TGA studies, water uptake of the films in aqueous medium, and soil degradation properties to observe the best possibility for its application.

Numerical Simulation on Failure Mechanism of Rock Slope Using RFPA

2011 ◽  
Vol 50-51 ◽  
pp. 568-572 ◽  
Author(s):  
Nu Wen Xu ◽  
Chu Nan Tang ◽  
Chun Sha ◽  
Ru Lin Zhang
Keyword(s):  
Rock Slope ◽  
Slip Surface ◽  
Process Analysis ◽  
Failure Process ◽  
Numerical Code ◽  
Natural State ◽  
Left Bank ◽  
Good Tool ◽  
Deep Rock ◽  
The Stability

This research applied a numerical code, RFPA2D (Realistic Failure Process Analysis) to evaluate the stability and investigate the failure mode of the high rock slope during excavations based on Strength Reduction Method (SRM). The corresponding shapes and positions of the potential slip surfaces are rationally simulated in different stages, and the related safety coefficients are obtained, which agrees well with the allowable minimum safety factors of the slope. The numerical results show that the safety coefficient drops from 1.25 at the natural state to 1.09 after excavation, and then increases to 1.35 after slope reinforcement. Moreover, the potential slip surface of the left bank moves into deep rock mass after taking support measures, which demonstrates the reinforcement is reasonable and efficient. The study shows that cracks and faults will cause crucial influences on the slope stability, and RFPA2D is a good tool to directly display the potential slip surface of the slope, which will offer valuable guidance for bolt support.

scholarly journals Hydro-Mechanical Effects of Several Riparian Vegetation Combinations on the Streambank Stability—A Benchmark Case in Southeastern Norway

2021 ◽  
Vol 13 (7) ◽  
pp. 4046
Author(s):  
Vittoria Capobianco ◽  
Kate Robinson ◽  
Bjørn Kalsnes ◽  
Christina Ekeheien ◽  
Øyvind Høydal
Keyword(s):  
Slope Stability ◽  
Methodological Approach ◽  
River System ◽  
Flood Management ◽  
Natural State ◽  
Mechanical Reinforcement ◽  
Climate Conditions ◽  
Salix Caprea ◽  
Stability Of Slopes ◽  
The Stability

Vegetation can be used as a nature-based solution (NBS) to restore rivers and mitigate water-triggered processes along streambanks. Roots are well known to improve the overall stability of slopes through hydro-mechanical reinforcement within the rooted zone. Vegetation-based solutions require the selection of species that are most suitable for specific locations, and they are aimed at restoring the natural state and function of river systems in support of biodiversity, flood management, and landscape development. Selecting a combination of different species along different zones of the riverbank can improve the conditions for the river system with regard to biodiversity and stability. Therefore, more studies are needed to investigate how the combination of a variety of different plant species can improve the stability of the riverbank. This paper presents a methodological approach for slope stability modeling including vegetation as well as the results obtained from a series of slope stability calculations adopting the proposed methodology. The analyses were carried out for critical shallow (≤3 m deep) shear planes of ideal benchmark slopes covered with four different plant combinations—(i) only grass, (ii) grass and shrubs, (iii) only trees, and (iv) trees, shrubs, and grass—for species typically found along streams in southeastern Norway. In this desk study, two types of tree species were selected, namely Norway spruce (Picea abies) and Downy birch (Betula pubescens). The Goat willow (Salix caprea) was selected as a shrub, while a common mixed-grass was chosen as grass. Vegetation features were obtained from the literature. The methodology was used for two main cases: (1) considering only the mechanical contribution of vegetation and (2) considering both the hydrological and mechanical reinforcement of vegetation. The main outcome of the numerical modeling showed that the purely mechanical contribution of vegetation to slope stability could not be decoupled from the hydrological reinforcement in order to have a realistic assessment of the roots improvement to the stability. The most critical shear surfaces occurred below the rooted zone in all cases, and the best performance was obtained using the combinations including trees. Considering the typical climate conditions in Norway, the hydro-mechanical reinforcement was most effective in the spring and for combinations including low height vegetation (i.e., grass and shrubs). The study concludes that a mixed combination of vegetation (trees, shrubs, and grass) is the most suitable for reaching the highest hydro-mechanical reinforcement of streambanks, together with erosion protection and boosting the ecosystem biodiversity. The current study can help practitioners determine which vegetation cover combination is appropriate for improving the current stability of a streambank with restoration practices.

Characterization of Lidocaine Transdermal Patches from Natural Rubber Latex

2013 ◽  
Vol 747 ◽  
pp. 103-106 ◽  
Author(s):  
Prapaporn Boonme ◽  
Hasleena Boontawee ◽  
Wirach Taweepreda ◽  
Wiwat Pichayakorn
Keyword(s):  
Drug Release ◽  
Natural Rubber ◽  
Physicochemical Properties ◽  
Rubber Tree ◽  
Natural Rubber Latex ◽  
Rubber Latex ◽  
Transdermal Patches ◽  
The Stability ◽  
Main Component

The mucous liquid of Hevea brasiliensis or Para rubber tree, called natural rubber latex (NRL), composes of cis-1,4-polyisoprene which can form a patch under suitable formulation. In this study, blank and 5% lidocaine-loaded NRL patches were formulated and then characterized for physicochemical properties as well as evaluated in vitro drug release and stability. The patches were observed for their appearances. Surface morphology of the patches was investigated using a SEM. XRD was employed to study the crystallinity of the drug, the patch, and the drug-loaded patch. The extractions of lidocaine-loaded patches were analyzed for drug contents by HPLC. In vitro drug release study was performed using modified Franz diffusion cells. The patches at initial preparation and after kept at 4, 25, and 45 °C for 3 months were investigated for the stability determination. The results suggested that NRL could be used as a main component in pharmaceutical transdermal patches with acceptable physicochemical properties. Lidocaine-loaded NRL patches provided desirable drug release but high storage temperatures could age the patches resulting in darken color and lower release amount.

Study on Nano SiO2 Synthesized by Gaseous Detonation under Different Initial Temperature

2011 ◽  
Vol 694 ◽  
pp. 180-183
Author(s):  
Hong Hao Yan ◽  
Shu Xiong Xi ◽  
Xian Chao Huang
Keyword(s):  
Particle Size ◽  
Initial Temperature ◽  
Xrd Analysis ◽  
Amorphous Structure ◽  
Gaseous Detonation ◽  
Mixed Gas ◽  
X Ray ◽  
Sio2 Powder ◽  
Main Component ◽  
Nanometer Sio2

Taking the mixed gas of the silicon tetrachloride, the air and the hydrogen as the explosion source, adjusting the initial temperature of the mixed gas and detonating it in the gaseous detonation tube, after washing, filtering with alcohol and drying, the nanometer SiO2 powder is obtained. The analysis on the nanometer SiO2 powder is carried on with X-ray fluorescence spectroscopy, transmission electron microscopy and x-ray diffraction instrument. By analyze the ingredient of the obtained product with x-ray fluorescence spectrometry, it is measured that its main component is SiO2; by XRD analysis, it is known that the generated SiO2 belongs to the typical amorphous structure; by TEM images, it can be seen that particle size are mostly between 20~30nm, the particle shape is spherical, also the dispersion is good. Under the conditions of the initial temperature 140°C, the product particle size is finer, and the dispersion is better.

The Stability and Reversibility of TiCl3 Doped LiBH4

2007 ◽  
Vol 1042 ◽  
Author(s):  
Ming Au ◽  
Arthur R Jurgensen ◽  
William A Spenser ◽  
Donald L Anton ◽  
Frederick E Pinkerton
Keyword(s):  
Ion Exchange ◽  
Transition Metal ◽  
Hydrogen Storage ◽  
Exchange Interaction ◽  
Xrd Analysis ◽  
Lithium Salts ◽  
Metal Halides ◽  
High Hydrogen ◽  
Capacity Loss ◽  
The Stability

AbstractIn an effort to develop reversible metallic borohydrides with high hydrogen storage capacities and low dehydriding temperature, modifications to LiBH4 with metal halides TiCl3 have been conducted. Adding TiCl3 to LiBH4 effectively reduced the dehydriding temperature through an ion exchange interaction by producing instable transition metal borohydrides and lithium salts. The material LiBH4+0.1TiCl3 desorbed 3.5wt% and 8.5wt% hydrogen at 150°C and 450°C respectively. Subsequent re-absorption of 6wt% hydrogen at 500°C and 70 bars was observed. The XRD analysis of the rehydrided samples confirmed the partial reformation of LiBH4. However, adding more TiCl3 made material more volatile and irreversible. TGA-RGA analyses indicated diborane evolution during dehydrogenation resulting in unrecoverable capacity loss and irreversibility. TiCl3 reduced LiBH4 stability and also made material irreversible.

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