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represents an average over rotations, of the SteinTomas restriction phenomenon.


Nanocrystalline nickel with an average diameter of about 16 nm and a facecentered cubic (fcc) structure was uniformly attached to the surface of carbon nanotubes (CNT) by wet chemistry.


According to the volume increase model of an average individual tree in a plant population and the theory of invariable final output, we put forward a new density model of plant population: Vβ=ANβ + B.


miconioides population ranged from 14.60% to 27.44%, with an average of 20.73%.


miconioides populations was relatively low (0.198,7), and the genetic similarity ranged from 0.655,7 to 0.811,9, with an average of 0.730,6.

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 In the statistical theory of superlattices in binary alloys, the dependence of the interaction energy upon atomic arrangements is taken into account by regarding the interaction energy in Bethe's theory as an average quantity depending on the degree of order and the composition of the alloy. Two simple assumptions concerning the functional relationship of the interaction energy with order and composition are made. The first is a linear function of order and composition. The second is a linear function... In the statistical theory of superlattices in binary alloys, the dependence of the interaction energy upon atomic arrangements is taken into account by regarding the interaction energy in Bethe's theory as an average quantity depending on the degree of order and the composition of the alloy. Two simple assumptions concerning the functional relationship of the interaction energy with order and composition are made. The first is a linear function of order and composition. The second is a linear function of the average numbers of pairs of atoms. The result of applying these assumptions to superlattices of the type AB is that the critical temperature as a function of the composition is a maximum for equal sumber of A and B atoms only when a certain relation between the coefficients in the assumed function is satisfied. In the cass of superlattices of type AB3 the theory of Bragg and Williams is used for simplicity. It is shown that when the composition varies, the maximum of the critical temperature may occur at any desired composition by a suitables adjustment of the coefficients in the assumed functions. There is thus a hope of removing the discrepancy between theory and experiment on this line. The anomalous specific heat at the critical temperature is also calculated for different compositions. In the case of the AB type of superlattices, Bethe's formula for the energy is no longer valid, and in order to calculate the specific heat, an approximate formula for the energy is obtained by analogy with the theory of Bragg and Williams. Finally, the problem of separation into more than one phase is briefly discussed.  在二元合金超格之统计力学理论中,原子间互作用能量,因原子之排列不同而异,其所生之影响,吾人擬於此篇中讨论之。吾人认为有Bethe氏理论中之相互作用能量,实为一平均值,其值因合金之秩序程度及其成分而异。吾人作二简单假设:一设相互作用能量为秩序及成分之线性函数,另一设其与原子对偶之数成线性函数。将此等假设应用於AB类之合金,则必须在所设函数中之系数间,有适当关系,合金之临界温度,始在成分为1:1时,有极大值。在AB_3类之合金,吾人乃应用Bragg及Williams二氏之理论以求简便。於此可证明若所设函数中之系数,可任意调整则所计算出之临界温度之极大值可在任何成分发生。故关於此点理论与实验不合之处,可望解决。又合金之反常比热,亦经算出。在AB类之合金,Bethe氏原来之能量公式不復可用,故另用与Bragg及Williams理论比较而得之公式计算。又关於合金可分为二相或多相之问题,此篇亦大略论及。  The recent opportunity of examining the faecal material of the waterscorpion Leccotrephes japonensis revealed a flagellate which had not previously been described from this host. After fuller investigation I found that it is a species new to science and should be referred to the genus Retortamona; I have named it Retortamonas leccotrephae sp. nov.The specimens of Leccotrephes japonensis used for studies on the parasitic flagellate R. leccotrephae, were collected from ponds on the outskirts of Shanghai, China.... The recent opportunity of examining the faecal material of the waterscorpion Leccotrephes japonensis revealed a flagellate which had not previously been described from this host. After fuller investigation I found that it is a species new to science and should be referred to the genus Retortamona; I have named it Retortamonas leccotrephae sp. nov.The specimens of Leccotrephes japonensis used for studies on the parasitic flagellate R. leccotrephae, were collected from ponds on the outskirts of Shanghai, China. Apart from studying the living flagellates, at the same time stained specimens were prepared for the detailed study of various structures. These specimens were fixed either in Hollande's or in Schaudinn's fluid; stained in Heidenhain's haematoxylin, and destained in 2％ aqueous phosphotungstic acid. Moskowitz' (1950) modification of the Protargol impregnation method was also used for staining.In the living state, the flagellare has a slender, slippershaped trunk with an anterior dorsal flexure. The mean body size, exclusive of the posterior spike, is 12.8μ×4.8μ. The length of the slender posterior spike varies from 4.6μ to 15.8μ. There are two flagella of unequal length. The longer one extends forwards and lashes rapidly, causing the animal to rotate and to pursue a special course. The shorter flagellum is directed backwards and usually lies in the cytostome; it moves in an undulating manner.In fixed and stained preparations, the flagellates, not including the posterior spike, show a sizerange of 6.2×2.2μto 15.6×5.4μ, with a mean of 11.9×3.4μ. The spike varied from 4.6μ to 13.6μ long, with an average length of 11.2μ. In general, a normal specimen of R. leccotrephae has a slender body; the anterior portion is narrower than the postcerior, and is markedly bent as shown in the living indivi.duals. The posterior portion of the body usually has a dorsal convexity, and the widest region is located near the twothirds of the bodylength from the anterior end.Near that edge of the nuclear membrane lying next to the cytostome, there are two minute, but separate, basal granules which give rise to the two flagella. The anterior flagellum is about as long as the body proper: much longer and more slender than the posterior flagellum, which usually lies within the cytostome, and commonly shows a series of two or three undulations; it often stains more deeply than the anterior flagellum.In hematoxylin preparations the nucleus is well stained, and clearly shows a layer of chromatin granules lying against the nuclear membrane, and a large central endosome, composed of a mass of granules.The cytostome is a large structure in this animal. It usually occupies about twothirds of the total length of the body proper. Along the margin of the cytostome there are two deeply staining fibres, the one on the right margin is longer than that on the left.Both the precystic forms and cysts of R. leccotrephae have been observed. The body of precystic individuals which are preparing to encyst, becomes smailer and rounds up; meanwhile, the chromatin of the nucleus condenses and forms a deeply staining endosome. The anterior flagellum is still disposed freely, and no cyst wall has as yet been formed. The borderline of the cytostome is distinct, but the two basal granules are visible only in favourable preparations. The mature cysts are nearly peanutshaped, and are about twice as long as wide. In the stained specimens they are about 4.6μ long and 2.4μ wide. The cyst wail is of uniform thickness, and the nucleus is visible at one end. The other conspicuous structures within the cyst are the two flagella and the cytostomial fibres, which are arranged as they are in the trophozoite, except that the anterior flagellum is here directed posteriorly.DISCUSSION & SUMMARYIn its general bodyform, R. leccotrephae closely resembles Mackinnon's R. agilis ('11) from cranefly larvae, and also Corradett's R. gryllotalpae ('37) from the mole cricket, but it is especially like Geiman's R. caudacus ('32) from the aquatic larvae ef certain beetles.  红娘华蛐的身体结构,一般与Mackinnon所述的R.(Embadomonas) agilis和Corradetti所述的R.grillotalpae相似,特别近似Geiman所述的R.caudacus(图15,16)。但红娘华蛐有大约等於体长2/3的大胞口,和长於或等於体长的针状尾巴,而且无论在生活时或固定染色後,头部均向背後扭曲(此较图1和15)。这些特性,显然与过去文獻中所记载的种类不同,故(氵夬)定为蛐属——新种。  Fineness modulus (F. M.) has served as an index of fineness of aggregates since it was first introduced by Prof. Duff A. Abrams in 1918. In the concrete mix design, the F. M. of sand governs the sand content and hence the proportions of other ingredients. But there are undesirable features in F. M.: it does not represent the grading of sand and manifests no significant physical concept.Prof. suggested an "average diameter" (d_(cp)) in 1943 as a measure of fineness of sand. In 1944, d_(cp) was adopted in 278144... Fineness modulus (F. M.) has served as an index of fineness of aggregates since it was first introduced by Prof. Duff A. Abrams in 1918. In the concrete mix design, the F. M. of sand governs the sand content and hence the proportions of other ingredients. But there are undesirable features in F. M.: it does not represent the grading of sand and manifests no significant physical concept.Prof. suggested an "average diameter" (d_(cp)) in 1943 as a measure of fineness of sand. In 1944, d_(cp) was adopted in 278144 as national standard to specify the fine aggregate for concrete in USSR. It was introduced to China in 1952 and soon becomes popular in all technical literatures concerning concrete aggregates and materials of construction.After careful and thorough investigation from ordinary and special gradings of sand, the equation of d_(cp) appears to be not so sound in principle and the value of d_(cp) computed from this equation is not applicable to engineering practice. The assumption that the initial average diameter (ν) of sand grains between consecutive seives is the arithmetical mean of the openings is not in best logic. The value of an average diameter computed from the total number of grains irrespective of their sizes will depend solely on the fines, because the fines are much more in number than the coarses. Grains in the two coarser grades (larger than 1.2 mm or retained on No. 16 seive) comprising about 2/5 of the whole lot are not duly represented and become null and void in d_(cp) equation. This is why the initiator neglected the last two terms of the equation in his own computation. Furthermore, the value of d_(cp) varies irregularly and even inversely while the sands are progressing from fine to coarse (see Fig. 4).As F. M. is still the only practical and yet the simplest index in controlling fineness of sand, this paper attempts to interpret it with a sound physical concept. By analyzing the F. M. equation (2a) in the form of Table 9, it is discovered that the coefficients (1, 2…6) of the separate fractions (the percentages retained between consecutive seives, a1, a2…a6) are not "size factors" as called by Prof. H. T. Gilkey (see p. 93, reference 4), but are "coarseness coefficients" which indicate the number of seives that each separate fraction can retain on them. The more seives the fraction can retain, the coarser is the fraction. So, it is logical to call it a "coarseness coefficient". The product of separate fraction by its corresponding coarseness coefficient will be the "separate coarseness modulus". The sum of all the separate coarseness moduli is the total "coarseness modulus" (M_c).Similarly, if we compute the total modulus from the coefficients based on number of seives that any fraction can pass instead of retain, we shall arrive at the true "fineness modulus" (M_f).By assuming the initial mean diameter (ν') of sand grains between consecutive seives to be the geometrical mean of the openings instead of the arithmetical mean, a "modular diameter" (d_m), measured in mm (or in micron) is derived as a function of M_c (or F. M.) and can be expressed by a rational formula in a very generalized form (see equation 12). This equation is very instructive and can be stated as a definition of mqdular diameter as following:"The modular diameter (d_m) is the product of the geometrical mean ((d_0×d_(1))~(1/2) next below the finest seive of the series and the seive ratio (R_s) in power of modulus (M_c)." If we convert the exponential equation into a logarithmic equation with inch as unit, we get equation (11) which coincides with the equation for F. M. suggested by Prof. Abrams in 1918.Modular diameter can be solved graphically in the following way: (1) Draw an "equivalent modular curve" of two grades based on M_c (or F. M.) (see Fig. 6). (2) Along the ordinate between the two grades, find its intersecting point with the modular curve. (3) Read the log scale on the ordinate, thus get the value of the required d_m corresponding to M_c (see Fig. 5).As the modular diameter has a linear dimension with a defin  細度模數用為砂的粗細程度的指標,已有三十餘年的歷史;尤其是在混凝土的配合上,砂的細度模數如有變化,含砂率和加水量也要加以相應的調整,才能維持混凝土的稠度(以陷度代表)不變。但是細度模數有兩大缺點,一個是模數的物理意義不明,另一個是模數不能表示出砂的級配來。蘇聯斯克拉姆塔耶夫教授於1943年提出砂的平均粒徑(d_(cp))來,以為砂的細度指標;雖然平均粒徑仍不包含級配的意義,但是有了比較明確的物理意義,並且可以用毫米來度量,這是一種新的發展。不過砂的細度問題還不能由平均粒徑而得到解决,且平均粒徑計算式中的五項,僅首三項有效,1.2和2.5毫米以上的兩級粗砂在計算式中不生作用,以致影響了它的實用效果。本文對於平均粒徑計算式的創立方法加以追尋和推演,發現其基本假設及物理意義,又設例演算,以考察其變化的規律性;認為細度模數還有其一定的實用價值,不能為平均粒徑所代替。至於補救細度模數缺點的方法,本文試由模數本身中去尋找;將模數的計算式加以理論上的補充後,不但能分析出模數的物理意義,並且還發現模數有細度和粗度之別。根據累計篩餘計算出來的F.M.應稱為“粗度模數”,根據通過量計算出來的才是“細度模數”。假定兩隣篩间的顆粒是... 細度模數用為砂的粗細程度的指標,已有三十餘年的歷史;尤其是在混凝土的配合上,砂的細度模數如有變化,含砂率和加水量也要加以相應的調整,才能維持混凝土的稠度(以陷度代表)不變。但是細度模數有兩大缺點,一個是模數的物理意義不明,另一個是模數不能表示出砂的級配來。蘇聯斯克拉姆塔耶夫教授於1943年提出砂的平均粒徑(d_(cp))來,以為砂的細度指標;雖然平均粒徑仍不包含級配的意義,但是有了比較明確的物理意義,並且可以用毫米來度量,這是一種新的發展。不過砂的細度問題還不能由平均粒徑而得到解决,且平均粒徑計算式中的五項,僅首三項有效,1.2和2.5毫米以上的兩級粗砂在計算式中不生作用,以致影響了它的實用效果。本文對於平均粒徑計算式的創立方法加以追尋和推演,發現其基本假設及物理意義,又設例演算,以考察其變化的規律性;認為細度模數還有其一定的實用價值,不能為平均粒徑所代替。至於補救細度模數缺點的方法,本文試由模數本身中去尋找;將模數的計算式加以理論上的補充後,不但能分析出模數的物理意義,並且還發現模數有細度和粗度之別。根據累計篩餘計算出來的F.M.應稱為“粗度模數”,根據通過量計算出來的才是“細度模數”。假定兩隣篩间的顆粒是兩篩篩孔的幾何平均值,以代替數學平均值(即斯氏平均?   << 更多相关文摘 
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