Water and heat fluxes above a lowland dipterocarp forest in Peninsular Malaysia     

Satoru Takanashi  Yoshiko Kosugi  Shinjiro Ohkubo  Naoko Matsuo  Makoto Tani  Abdul Rahim Nik 《水文研究》2010,24(4):472-480

We measured the fluxes of sensible and latent heat between a low‐land dipterocarp forest in Peninsular Malaysia and the atmosphere. No clear seasonal or interannual changes in latent heat flux were found from 2003 to 2005, while sensible heat flux sometimes fluctuated depending on the fluctuation of incoming radiation between wet and dry seasons. The evapotranspiration rates averaged for the period between 2003 and 2005 were 2·77 and 3·61 mm day^?1 using eddy covariance data without and with an energy balance correction, respectively. Average precipitation was 4·74 mm day^?1. Midday surface conductance decreased with an increasing atmospheric water vapour pressure deficit and thus restricted the excess water loss on sunny days in the dry season. However, the relationship between the surface conductance and vapour pressure deficit did not significantly decline with an increase in volumetric soil water content even during a period of extremely low rainfall. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

Reliability analysis of shallow foundations in reference to design codes development     

Yusuke Honjo  Makoto Suzuki  Minoru Matsuo 《Computers and Geotechnics》2000,26(3-4):331-346

In this study, FORM analysis is carried out for shallow foundation of a typical building in order to evaluate relative magnitude of uncertainties involved in the force and the resistance sides. The distinguished feature of this study is to take into account the uncertainty of the earthquake force as much as possible. Tthis is because, the seismic design dominates major part of structural design in Japan, and without referring to this problem, no useful information of practical value is gained. The results of the FORM analysis exhibited the reliability index values between 2.0 to 3.5, which is considered to be in a reasonable range. Since the 50 year maximum earthquake force is considered in the reliability calculation, calculated reliability index values are for the period of 50 years. The sensitivity factor obtained in a case more realistic ground variability is taken into account exhibited values not very different from those obtained in the upper structures.  相似文献   

A study on the interaction between ferric ion and silicic acid in hydrosphere: Si-containing ferruginous deposits formed in neutral hot spring waters     

Gaowa Naren  Akane Miyazaki  Motoyuki Matsuo  BAI Shuqin  Kotaro Yonesu  Yoshihiro Okaue  Takushi Yokoyama 《中国地球化学学报》2013,32(1):27-34

Five ferruginous deposit samples formed from neutral hot springs were analyzed to determine whether they consisted of a mixture of silica, hydrous iron oxide or iron silicate by differential thermal analysis (DTA), infrared (IR) spectroscopy, powder X-ray diffraction (XRD), and 57Fe Mssbauer spectroscopy. The Si/Fe atomic ratios of the deposits ranged from 0.25 to 0.45, and were smaller than those of hisingerite (12), but apparently close to those of siliceous ferrihydrite (0.250.5). Si was confirmed to be present as monomeric or oligomeric silicate from the Si-O stretching vibration frequencies on the IR spectra. Judging from the results of DTA, which minerals starting to produce after heating, and a relationship between Si-O stretching vibration frequency and Si/Fe atomic ratio proposed by Henmi et al. (1981), all the deposits in this study were concluded to be mixtures of various siliceous ferri-hydrites with low and high Si/Fe atomic ratios. Moreover, by comparing the chemical properties of hot spring waters, the formation conditions of siliceous ferrihydrite were also discussed.  相似文献   

Annual and Diurnal Variation of Meteor Rates by the Forward-Scatter Radio Observation     

Sadao Okamoto  Kimio Maegawa 《Earth, Moon, and Planets》2008,103(1-2):65-68

Forward-scatter radio meteor observations have been made at Japan since 1996 using inexpensive and low-end equipment. The activity of some major meteor showers and the seasonal variability of sporadic meteors in 2006 are presented.  相似文献   

Establishment of chemical equilibrium in the volcanic gas obtained from the lava lake of Kilauea,Hawaii     

Sadao Matsuo 《Bulletin of Volcanology》1962,24(1):59-71

The establishment of gaseous chemical equilibrium in gases obtained from Kilauea lava lake was studied. Using Shepherd’s elaborate analytical data, we examined six chemical reactions in the gas phase and concluded that they were in equilibrium. The gases reflected the « quenched » equilibrium conditions of temperature within a range from 1,000° C to 1,200° C under 1 atmosphere. The gas samples had been collected over a period of three years in different localities of the same lava lake. Although the analytical result was varied considerably for each sample, the establishment of chemical equilibrium was confirmed in five of the six reactions, the exception being due to sulfur trioxide in the sixth.  相似文献   

Long-term creep experiment on some rocks observed over three years   总被引：1，自引：0，他引：1  

Hidebumi It  Sadao Sasajima 《Tectonophysics》1980,62(3-4)

Since August 1974 the authors have been carrying out an experiment on creep by bending three small granite beams and three gabbro beams. While making measurements, an optical flat is set to produce interference fringes of Na-D light upon the upper polished surface of the beam, which was previously bent convex upward. By analyzing the fringes the profile of the surface is determined with in an accuracy of one-tenth of a wavelength. The routine determination of profiles gives a change in the amount of bending with time.A similar experiment on two large beams of granite was carried out for 21 years by Kumagai and Itô. It took 10 years in order to find out the secondary creep of granite. However, in this three-year experiment it has been found that the secondary creep of the granite specimens gives a viscosity of about 1 · 10²⁰ poise, which is comparable to that obtained over 20 years in the previous experiment (Kumagai and Itô). As for the gabbro specimens, the present authors cannot yet definitely recognize the secondary creep, because gabbro creeps much more slowly than granite.Both this and the previous experiments have revealed that the creep of rocks does not show a steady and monotonous progress, but a repeated “turn back” with various periods, some of which are longer than one year. In order to explain the creep accompanied by the “turn back” phenomenon, the authors venture to hypothesize that the elastic constants of a test-piece slightly vary with time during the advance of creep.  相似文献   

Phase transition of potassium sulfate,K2SO4 (II); dielectric constant and electrical conductivity     

Michihiro Miyake  Mutsumi Matsuo  Mayumi Hata  Shin-ichi Iwai 《Physics and Chemistry of Minerals》1981,7(2):88-90

The phase transition of K₂SO₄ has been investigated by measurements of the dielectric constant and electrical conductivity, correlated with the structural point of view. Using single crystals, the temperature dependences of the dielectric constants and electrical conductivities were measured at frequencies of 0.3, 1, 3, and 5 MHz in the temperature range from 20° to 640 °C. Within this range, the dielectric constant does not reach a maximum, but near the phase-transition temperature at 587° C, the dielectric constant along the c axis shows a larger discontinuity than those along the a and b axes. The temperature dependence of the dielectric constant is consistent with the disordered structure of the high temperature form. Based on the parabolic increase of the dielectric constant in the temperature range from 582° to 587° C, it is likely that the phase transition propagates through an intermediate state. The electrical conductivity coefficients of K₂SO₄ increase with increasing temperature, exhibiting semiconducting character above the phase-transition temperature. In the high-temperature form, the electrical conductivity along the a axis exceeds that along the c axis. Since the electrical conductivity of K₂SO₄ is mainly ionic in character, the migration of K⁺ ions makes a major contribution to the conduction process.  相似文献   

Relationship between the increase temperature and variation of ozone level over the Antarctica and Tibetan plateau in spring   总被引：1，自引：0，他引：1  

Gao Dengyi  Sadao Kawagochi 《大气科学进展》1986,3(4):489-498

Based on the ozone and aerological sounding data at Syowa Station (69o 00'S, 39o35'E), Antarctica during 1966－1979 and Lhasa Station (39o40'N, 91o08'E), Tibetan Plateau during 1979－1983, the processes of temperature increase in spring over the Tibetan Plateau and the Antarctica are compared in this paper, and the relationship between the increase of air temperature and variation of total ozone and ozone partial pressure is analyzed. It is found that: (1) The process of temperature increase over the Tibetan Plateau is quite different from that over the Antarctica in spring. This is a proof that the heating effects of their ground surface on the atmosphere are of great difference; (2) Sudden increase of total ozone is always associated with sudden warming in the stratosphere over the Antarctica, but sudden decrease of total ozone is associated with sudden warming in the troposphere over the Tibetan Plateau in spring; and (3) There is a good positive correlation, with a correlation coefficient of about 0.85, between the temperature increase and variation of ozone partial pressure in the stratosphere over the Antarctica in spring.  相似文献   

Chemistry of rainwaters in the south Pacific area of Russia     

V.A. Chudaeva  S.G. Urchenko  O.V. Chudaev  K. Sugimory  M. Matsuo  A. Kuno 《Journal of Geochemical Exploration》2006,88(1-3):101

On the south-eastern edge of Russia, the chemical composition of rainwater is controlled by sea salts, terrestrial material, as well as volcanic (Kuril islands volcanic area) and anthropogenic emissions, mostly in the southern part of the area. The predominant major ions of the Primorye, Sakhalin and the Kuril Islands rainwaters were respectively HCO₃⁻–SO₄²⁻, Ca–Na, and of Cl–Na. Concentration of trace elements changes within 1–2 orders of magnitude but some difference in the distribution of the elements between continental and island rainwater is found. The concentration of the chemical elements in the particulate fraction varies from < 10% to 90% of the total concentration (dissolved + particulate) with the following distribution: Tl, Na, Ca, Sr, Zn, Cd (< 10%)–Be, Th, Bi, Rb, U, K, Sc (10–20%)–Cu, Mn, Mg, Mo, Se, Ba, Ni, As, Ag, Cs, Co, Y, Ga, V (20–50%)–Sb, Pb, Ge, Cr, Fe, Al (50–90%).The concentration of elements of the particulate fraction of the rainwater usually is significantly different from concentrations in the crust, including both higher and lower concentrations. The terrestrial contribution to dissolved elements was evaluated and follows the decreasing order: Fe > K, Mg, Ca > Ba, Sr > Na (65–1%). Close order was found for total (dissolved and solid) concentrations. Sea salt contribution to dissolved element concentration in the rainwater decrease in the following order: Cl, Mg > K, SO₄ > Ca > HCO₃⁻, Ba, Fe (78–0.1%). Calculation of anthropogenic and volcanic inputs for two ions (Cl⁻ and SO₄²⁻) shows that anthropogenic inputs for the Vladivostok and Yuzno-Sakhalinsk cities can be evaluated as 15–20% of Cl⁻ and up to 80–90% of SO₄²⁻. Volcanic components in the Kuril Islands, where anthropogenic inputs are absent, can reach up to 76% of SO₄²⁻ and 36% of Cl⁻.  相似文献   

Geochemistry of recent hydrothermal systems of Mendeleev Volcano, Kuril Islands, Russia     

O. Chudaev  V. Chudaeva  K. Sugimori  A. Kuno  M. Matsuo 《Journal of Geochemical Exploration》2006,88(1-3):95

Among the thermal waters of Mendeleev Volcano three main types can be distinguished: sodium-chloride, acid-sulfate and chloride–sulfate–bicarbonate waters. Contents and behaviors of siderophile, chalcophile, lithophile, and rare-earth elements are discussed. These data, together with the result of isotopic studies (oxygen and hydrogen), are used to discuss the origin of these waters. From the three types of thermal waters, only acid-sulfate waters have a significant input on the chemical composition of the surrounding surface waters.  相似文献