巻号一覧
11 巻 (1955 - 1956)
- 4 号 p. 121-
- 3 号 p. 81-
- 2 号 p. 41-
- 1 号 p. 1-
11 巻, 4 号
選択された号の論文の15件中1～15を表示しています
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丸山 栄三, 高砂 学1956 年 11 巻 4 号 p. 121-123
発行日: 1956/03/31
公開日: 2010/02/25
ジャーナル フリーDr. S. SUZUKI & S. SHIGETOMI have computed the thermal diffusivity of soil by using the equation
K=Δθ/Δt/Δ2θ/Δz2……(1)
In practice, the value of Δ2θ/Δz2 is determined by the following approximate formula.
Δ2θ/Δz2=(θ1-θ2/z1-z2-θ2-θ3/z2-z3)/(z1+z2/2-z2+z3/2)
=θ1-2θ2+θ3/(Δz)2……(2)
where θ1, θ2 and θ3 are soil temperature at z1, z2 and z3 respectively, and we are to take z1-z2=z2-z3.
The difficulty arises in attempt to get accurate value of Δ2θ/Δz2, since they used the glass thermometer.
The authors deviced a combination of two thermocuples to get the accurate values of (θ1-2θ2+θ3) as shown in Fig. 1. This arrangement is able to obtain the above value to the order of 0.02C.
It is noted that the diffusivity by using the equation (1) has to be used only in the case of ∂θ/∂t≠0 and ∂2θ/∂z2≠0 in the distribution of the soil temperatures in time and depth. From our experience, the proper length of Δz is from 2 to 3cm. Soil moisture contents are obtained by the Soil Moisture Ohm meter (Fiberglass Soil Moisture Unit Modls 351 & 375).
Observation have shown that the diffusivity of the soil decreases with the increase of the soil moisture contents, as the water content is greater than 28%. (see Tab. 1, and Fig. 2.)抄録全体を表示PDF形式でダウンロード (373K) -
荒井 哲男1956 年 11 巻 4 号 p. 124-126
発行日: 1956/03/31
公開日: 2010/02/25
ジャーナル フリーThe details of the in and out flow of heat just at the ground surface in the open field and frame are shown in Fig. 1 (a), (b) and the well known formulae (1) and (2) is to hold true in each case. Assuming that the temperatures of the ground surface on the open field and frame were identical, (3) is obtained subtracting (2) from (1) and taking the daily mean values, the formula (4) is obtainable.
Each side of this formula was calculated separately by the data measured in different days. When they are equal, the mean temperature in the farme on one day is equal to that in the open field on the other day. When the left side value was greater than the right, this heat difference must be supplied in to the frame on one day, to get the same mean temperature of the open field on the other day.
The calculated values from this formula by using the diurnal mean data in Tokyo from 1876 to 1948, are shown in Fig. 2. In this diagram, the curve I denotes the daily variation of heat of the left side values, and the curve II denotes those of the right sides. For example, it is easely seen from this figure, that the frame on the 1st March is equal to the open fields on 5th April in respect of mean temperature, and that in order to get the mean temperature of the open field on the 1st May, they supplying heat in the ground surface of the frame is 160 calories.
There is a question when the deficient heat is to be supplied. However it is clearly understood from Fig. 3 that this heat is to be added during the night as the diurnal amplitude of temperature on the frame is larger than that of the open field.抄録全体を表示PDF形式でダウンロード (469K) -
阿部 亥三, 高橋 昌一1956 年 11 巻 4 号 p. 127-129
発行日: 1956/03/31
公開日: 2010/02/25
ジャーナル フリー昭和27年に馬鈴薯の畦の方向を変えた場合の微気象の差異並に生育収量差異について調査し次の結果を得た。
1. 地温: 生育前期は南北畦匠比し東-西畦は低温であるが, 生育後期は逆に東西畦の方が高温となつた。南西-北東畦は東-西畦に, 南東-北西畦は南-北畦に近い経過を示した。
2. 畦間気温: 生育の主要期間を通じて東西畦の方が南北畦より高温を示し, 南西-北東畦及び南東-北西畦は前二者のほぼ中間の値を示した。このような畦間気温の差異は特に圃場の主風向どの関係が大きいものと推測された。
3. 馬鈴薯の地上部生育では統計的に有意性の認められたのは8月11日の調査で東-西畦の茎太が太い (5%の危険率) ことのみであつた。
4. 塊茎分化は南西-北東畦が最も早く, 次いで南北-畦, 南東-北西畦, 東-西畦の順の如くに推察された。
5. 収穫期の総薯重, 中薯以上の重量並に大薯重量では南西-北東畦が最も優り, 次いで南-北畦, 南東-北西畦の順となり, 東-西畦が最も劣つた。抄録全体を表示PDF形式でダウンロード (489K) -
第4報 柞蚕卵の低温接触が孵化並びに作柄に及ぼす影響山崎 寿, 西村 国男, 山田 たけを1956 年 11 巻 4 号 p. 130-132
発行日: 1956/03/31
公開日: 2010/02/25
ジャーナル フリー柞蚕卵の産下後1日目から孵化前日までの間に1回ずつ2.5℃又は5℃の低温接触を1日間～9日間行い, その孵化状態と幼虫を飼育してその営繭歩合とを調査し次の結果を得た。
(1) 柞蚕卵に低温 (5℃) 接触すれば接触時期の如何に拘らず孵化歩合が減少する。又特に産卵1日目が少い。
(2) 低温接触の期間が長い程, 孵化歩合が不良で死卵歩合が多く又孵化期間が長くなる。
(3) 柞蚕卵に低温接触すれば幼虫期に病蚕を多発し営繭歩合を著しく減少する。抄録全体を表示PDF形式でダウンロード (479K) -
太田 巖, 本木 茂1956 年 11 巻 4 号 p. 133-135
発行日: 1956/03/31
公開日: 2010/02/25
ジャーナル フリーIn order to obtain the fundamental data about the available shelterhedges, we investigated the climatic factors, chiefly wind velocity and air temperature, near the hedges at Udagawa nursery of Tochigi Prefecture in October 1954. This hedges consisted of Hinoki were 3m high with a width of 1m and void ratio of the hedges was about 10%.
The results of field measurements are as follows.
(1) The wind velocity at the windward point on 5 times the hedge height reached 116% to the standard wind velocity at the leeward point on 16h (h=the hedge height). At leeward points on 2h, 4h and 8h, 0%, 29% and 55% respectively to the standard wind velocity. We found that the wind velocity was changed remarkably between the shelter-hedge and the leeward point about 4h.
This trend was as same as that of evaporation.
These measurements were done at 30cm high above ground surface.
(2) As to air temperature at 30cm high above ground surface, if it blows the wind, the air temperature near the hedges was higher in the daytime and lower in the night-time than that of other place. But if it does not blow, there was not any difference everywhere.
As to ground temperature, it was always high at leeward place near the hedges except the case of rainfall.
Above mentioned results were obtained when it blew northern wind.抄録全体を表示PDF形式でダウンロード (2817K) -
1956 年 11 巻 4 号 p. 135
発行日: 1956年
公開日: 2010/02/25
ジャーナル フリーPDF形式でダウンロード (117K) -
三沢 春郎1956 年 11 巻 4 号 p. 136
発行日: 1956/03/31
公開日: 2010/02/25
ジャーナル フリーPDF形式でダウンロード (190K) -
(第2報) 水温分布調査の基礎理論について小沢 行雄1956 年 11 巻 4 号 p. 137-142
発行日: 1956/03/31
公開日: 2010/02/25
ジャーナル フリーThe following relation (10) was obtained as the foundamental differential equation of the change of water temperature from the physical research of the heat balance at water surface.
θ(x, t)-{k1+Lk2αb/k1+Lk2αθa(t)+R(t)/k1+Lk2α-Lk2β(1-b)/k1+Lk2α-α2κ1C1√2π/τ/k1+Lk2αsin(2π/τt+ε1)}
=-Ch/k1+Lk2α(∂θ/∂t+v∂θ/∂x)……(10)
Resolving the equation (10) by means of the Laplace-transformation, the equation (18) was obtained. The comparison of the computing value from (18) with the observed value was showed in fig. 1 & 2. The coincidence was not good.
But in the diurnal average value the coincidence was very good. So the following equation (25), which gives the diurnal average temperature, will be able to be used to determine the distribution of the diurnal average water temperature.
θ(x)=(A0+B0+C0)-(A0+B0+C0-E0)e-x/kv……(25)
where A0=k1+Lk2αb/k1+Lk2α·θa, B0=(1-s)R′-B/k1+Lk2α,
C0=-Lk2β(1-b)/k1+Lk2α, E0=θx=0, k=Ch/k1+Lk2α.抄録全体を表示PDF形式でダウンロード (743K) -
坂上 務1956 年 11 巻 4 号 p. 143-146
発行日: 1956/03/31
公開日: 2010/02/25
ジャーナル フリー過冷却雲中で沃化銀の種播きをした結果, その効果が認められ, 極めて短時間に沃化銀結晶粒子の多く存在する所に霧氷の増加が認められた。そしてこれは Houghton その他の理論とも大体一致することが認められ, 人工降雨の研究に一つの結果を提供したものと思われる。抄録全体を表示PDF形式でダウンロード (3263K) -
3. 穂波上の乱流拡散現象井上 栄一1956 年 11 巻 4 号 p. 147-151
発行日: 1956/03/31
公開日: 2010/02/25
ジャーナル フリーMaking use of the informations about the characteristics both geometrical and dynamical of the predominant turbulons which give rise to the waving plants phenomena (“HONAMI”) over cultivated fields such as rice and wheat field, several turbulent diffusion phenomena of particles such as smoke and agricultural chemicals over these fields are theoretically dealt with.
The scale ∧ and the velocity V of the predominant or the coupling turblon are related to the measuring height, the zeroplane displacement, the roughness parameter and the mean wind velocity. Two parameters characterizing the turbulent diffusion phenomena are introduced as the life-time τ=∧/V and the turbulent diffusion coefficient K=∧V=τV2. The dependence of these two parameters upon the mean wind velocity is considered, in particular being taken the dependence of both ∧ and V upon the mean wind velocity into account, and it is made clear that the diffusion starts to predominate at the critic al wind velocity of the waving plants phenomena.
Three dimensional scales of the predominant turbulon are considered and the remarkable differences in the life-times of predominant turbulon with respect to the directions, longitudinal, transversal and vertical, are pointed out. In particular, the longitudinal life-time is shown to be nearly eight times those in other two directions. One of the earlier results of smoke puff experiments extended over sea surface is made use of being compared to this theoretical anticipation, in which the longitudinal elongation of smoke puff is much predominant and the rate of elongation is in accord with the theoretical result based on the modern similarity hypotheses, i. e., the length of smoke puff increases in proportion to the three-halves power of the diffusion time.
The contributions of larger scale turbulons besides those of the coupling turbulons are dealt with, too. The scale ∧l and the velocity Vl of the larger turbulon are shown both in proportion to the-wind velocity at the measuring height. Near the ground surface usually the life-time τl of larger turbulon is shown independent of the height and much larger than the life-time τ of coupling turbulon. The meandering phenomenon of a smoke plume is attributed to the occasional contribution of these larger scale turbulons.抄録全体を表示PDF形式でダウンロード (769K) -
三沢 春郎1956 年 11 巻 4 号 p. 152-153
発行日: 1956/03/31
公開日: 2010/02/25
ジャーナル フリーPDF形式でダウンロード (274K) -
八鍬 利助1956 年 11 巻 4 号 p. 154-155
発行日: 1956/03/31
公開日: 2010/02/25
ジャーナル フリーPDF形式でダウンロード (289K) -
三沢 勝衛, 三沢 春郎1956 年 11 巻 4 号 p. 156-157
発行日: 1956/03/31
公開日: 2010/02/25
ジャーナル フリーPDF形式でダウンロード (282K) -
1956 年 11 巻 4 号 p. 157
発行日: 1956/03/31
公開日: 2010/02/25
ジャーナル フリーPDF形式でダウンロード (159K) -
三原 義秋1956 年 11 巻 4 号 p. 158-160
発行日: 1956/03/31
公開日: 2010/02/25
ジャーナル フリーPDF形式でダウンロード (575K)
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