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The material presented here is a synopsis of the Ph.D thesis of the author, cf.


Compound 4, 5, 6, 7, and 8 were synthesized from 4benzoyl1,5diphenyl1Hpyrazole3carboxylic acid 1 as a starting material.


Inverse computation of opticalabsorption coefficient in inhomogeneous material with varied thermal conductivity


It showed that the bromide in the rosin glycerin ester decomposed faster than the ester; hence it may be used as fireresistant material.


The biomimetic threedimensional porous composite can serve as a kind of excellent scaffold material for bone tissue engineering because of its microstructure and properties.

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 The purpose of this paper is to discuss Prof. method of analyzing twoway reinforced concrete slab. This method is based upon the equilibrium of forces under ultimate loading, and consequently the effect of plasticity of the material is included in consideration. If we use this method to design two way reinforced concrete slab, We should not only have much saving of steel, but also a saving of labour in computation. No matter that the slab is continuous over how many spans of unequal lengths, it can be... The purpose of this paper is to discuss Prof. method of analyzing twoway reinforced concrete slab. This method is based upon the equilibrium of forces under ultimate loading, and consequently the effect of plasticity of the material is included in consideration. If we use this method to design two way reinforced concrete slab, We should not only have much saving of steel, but also a saving of labour in computation. No matter that the slab is continuous over how many spans of unequal lengths, it can be easily analyzed, one by one, as a single span slab.  本文的目的是介紹蘇聯格娃斯捷夫教授的計算双向板的公式。這個公式是考慮板在極限平衡狀態,考慮了材料的塑性。用此方法計算雙向板,不但鋼筋經济而計算簡便。無論是多跨的板或不等跨的板,都可以视為單跨板來考虑,本文討論了格娃斯捷夫公式的基本理論,並将此理論应用到不規则形狀板的计算方面。  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?  Plasticizing agent is an organic surfaceactive admixture for cement mortar and concrete. It may be introduced also as an "addition" to the clinker during the grinding process in the manufacture of plasticizing Portland cement. In the USSR, the plasticizing agent under the name of "has been extensively and successfully used in construction works.The plasticizing agent is prepared by chemical treatment of the waste from the alcoholic fermentation of sulfite liquor in pulp manufacture. It contains calcium lignin... Plasticizing agent is an organic surfaceactive admixture for cement mortar and concrete. It may be introduced also as an "addition" to the clinker during the grinding process in the manufacture of plasticizing Portland cement. In the USSR, the plasticizing agent under the name of "has been extensively and successfully used in construction works.The plasticizing agent is prepared by chemical treatment of the waste from the alcoholic fermentation of sulfite liquor in pulp manufacture. It contains calcium lignin sulphonate as an effective component and thus possesses hydrophilic property. Due to the adsorption of the agent, a colloidal layer is formed on the surface of the cement particle; hence the effective dispersion and the increase of lubricity between the particles.Following the Soviet experience of CCB, the MaterialsTesting and Research Laboratory of Shanghai Civil Engineering Bureau successfully experimented with the preparation of thermal polymer of the plasticizing agent, and a series of tests on the characteristics of the agent were made. This paper attempts to describe the method of preparation and the main properties of the agent.The addition of the agent in an amount of 0.1—0.2% of cement (dry weight) markedly improves the workability and the texture of the mortar and concrete mixtures. It reduces the water requirement and the cement content. It improves the impermeability and durability of the hardened mortar and concrete.The agent has a retarding effect on the setting of cement. It lowers the early strength of mortar and concrete, while the strength of later age is higher than those without admixtures. The use of CaCl_2 accelerator in 0.5—1% of cement by weight speeds up the rate of development of the early strength.The proper dosage of the agent depends upon the properties of cement. Therefore, certain tests should be made with the specified cement and aggregates on the job before the adoption of the agent.  本文介紹亞硫酸鹽酒精液滓塑化劑實驗室中的試製以及對於水泥膠砂及混凝土技術性能方面的作用。首先說明一些塑化劑的理論及亞硫酸鹽酒精液滓的技術規格,再簡要的介紹上海市政工程局材料試驗研究所試驗研究的經過和結果;最后综合蘇聯對於塑化劑和塑化水泥使用的先進經驗。塑化剂是一種有機的表面活動性物質,利用造紙工業发液進行酒精發酵所得的液滓。加入微量的塑化劑——約為水泥重量的0.1—0.25％,可以顯著的改善膠砂和混凝土的性質。在增加流動性、改善和易性和提高耐久性方面,有十分的效用,尤其是對節約水泥用量有极大的意義。祖國的建设事業正迫切需要這類新型的建築材料,因此提供一些试驗研究結果,以供国家主管機關和科技工作同志們深入研究和推廣使用時的參考。   << 更多相关文摘 
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