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(13(3):31-37)流動方程式及其在土壤水分移動之應用
No full textI. EVOLUTION OF FLOW EQUATION
Water always moves from higher potential site to lower potential site. The basic equation describing the relation between the velocity of flow and the potential difference is given by Darcy’s law, which is based on the experimental observation. The simplest example leading to Darcy’s equation is given in the follwing. In this case, it is one dimensional saturated flow.
本文敘述流動方程式（Flow Equation）的誘導及其在土壤水分移動之應用。在本文所舉之例子可解該方程式而知水分移動之情形
(15(2):1-5)RAPID CHEMICAL METHOD OF ANALYSIS FOR NITROGEN, PHOSPHORUS AND POTASSIUM IN PLANT TISSUE
No full text多年來作農業研究的人常有一種感覺，就是用少數樣品作精細的分析不如採取多數的樣品作準確度較差的分析。這種要求常使我們覺得需要將過去的分析方法加以修改而使它更適台於我們的目的。一般將分析法微量化可減少操作上的一些負擔，但如能將分析缺的部分操作簡化，在多數樣品分析工作上的幫助也同樣值得重視。本研究室多年來從事於植物體的分析工作，經屢次改良漸近乎理想而成一分析系統。現將彙編成文以供大家參考，並有不足之處請大家指教。
The paper describes the mothod for the determination of nitrogh, phosphorus and potassium in plant tissue which is adapted by Plant Nutrition Laboratory (TARI) in its routine analysis The method is suitable for handling large samples and has some advantages over other conventional methods so far as simplicity and minimum of cost are concerned. In principle, the method uses sulfuric perchloric acid digestion and subsequent determination of nitrogen phosphorus and potassium by Conway’s micro-diffusion acid titration, molybdate blue spectrophotometry and flamephotometry, respectively, Precautions in using this method are carefully described and explanations given to make the experimenter understand the basic principles involved
(17(1):19-21)NOTE ON THE SULFURIC PERCHLORIC ACID DIGESTION FOR NITROGEN DETERMINATION OF PLANT SAMPLE (ABOUT THE LOSS OF NITROGEN)
No full text筆者在「大量植物樣本氮磷鉀的迅速測定法」中曾介紹過使用硫酸過氯酸分解法以測定氮素之方法。該法在屢次試驗中充分表示了與標準Kjeldahl氏法一致的結果。事後筆者再進一步使用了數種純粹有機氮化合物做試料，仍與標準Kjeldahl氏法做比較。結果出乎意料的該法比Kjeldahl氏法得了較高的測定值。筆者又再檢討予備分解時間與過氯酸的用量問題，結果發現如過氯酸使用不當時會引起氮的損失。綜合上面的結果筆者覺得有把詳細的情形報告給大家的必要，以供大家參考並希指正。
Plant sample is digested with sulfuric acid only, which is called predigestion. After predigestion, perchloric acid is added to complete the digestion. The end of predigestion is indicated by 1) solution of the sample, 2) color change from black to dark brown, 3) small amount of fume etc. Perchloric acid in excess amount caurses loss of nitrogen. Preliminary test is necessary for the beginner. Perchloric acid treatment in devided dosage is also helpful to keep digestion from excess of oxidant
(17(2):46-48)The use of sulfuric acid for the determination of calcium and magnesium in plant sample by EDTA method
No full text在植物體樣本的分解濕式法的應用甚廣，其優點已為大家所知。通常使用的酸包括三種即硫酸，過氯酸及硝酸等。硫酸的存在在鈣的測定場合常被人憂慮。其原因為硫酸與鈣生成硫酸鈣而不易溶解的緣故。因此在測定鈣的時候硫酸被認為不可使用。在另一面硫酸的存在在分解時却有不少用處，如使分解進行順利，防止爆炸，不須多照顧等優點。因此在大量樣本的處理上硫酸的使用甚有價值。為了上述的原因筆者認為對於硫酸的影響有進步檢討的必要。結果發現以本文所述的測定法硫酸的存在在鈣量少於4%時並不發生影響。不但如此，尚可利用硫酸鈣在酒精溶液的難溶性而除去鈣。此法在測定鎂時對高鈣量的樣本很有價值。
Sulfuric acid used in the wet digestion of plant sample puts some limit to the determination of calcium. According to the method described here, as high as 4% of the calcium in plant sample can be safely determined.
The sulfuric acid can also be used for partial seperation of calcium in alcoholic solution, which makes the magnesium determination more accurate when the sample contains high amount of calcium. Alcohol solution of 50% concentration was found satisfactory for this purpose without removal of alcohol before titration
(17(2):49-50)Determination of Nitrate by Microdiffusion
No full textConway氏的擴散法在大量樣本的銨態氮定量上確有很多的幫助，如果用簡單的方法能把硝酸態氮還原成銨，則擴散法必為硝酸態氮定量的良法。Conway氏曾使用Devada合金以達此目的。亦有用硫酸鈦的方法，前者有產生氫氣之缺點，後者適當的試藥難以獲得。筆者曾用鋅粉及硫酸第一鐵為還原劑，而得良好的結果，故提供大家參考。
此法應用於低濃度之試液甚理想，較其他比色法為簡便，對較濃之試液亦可應用自如。
Zinc powder and ferrous sulphate are used as reducing agents for the determination of nitrate by microdiffusion. The ammonia is absorbed in boric acid acid titrated with 0.002N acid. No hydrogen is evolved as in using Devada alloy. The method is simple and suitable for the solution of low concentration ( 1 to 6 ppm of nitrogen using 30 ml of sample solutin). The recovery is about 96%
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Discussion on current methods of soil testing and plant analysis used in TARI
No full text土壤速測與植體分析為瞭解土壤肥力狀況及作物營養狀態快速而有效的方法。因應不同的土壤與作物，土壤速測與植體分析方法繁多，更由於農民之需求標準逐日提高，科技之進步，土壤速測與植體分析方法不斷地改進，分析儀器之使用亦由簡單的光度計起發展成今日的高性能儀器（如ICP，AA等），本文就農試所農化系經常使用的土壤速測與植體分析方法簡單的說明和討論，並對未來的發展提出一個瞻望，以供參考。
Soil testing and plant analysis are means of assessing soil fertility and plant nutrient element status which have a considerable history of development and use.
Various procedures have been developed and improved which aims to evaluate the soil fertility and plant nutrient status more precisely. Recent development of multi-elementanalyzers such as inductively-coupled plasma emission spectrometer (ICP) favours the use of multi-element extrcting reagents instead of traditional single element reagents.
This paper describes briefly various procedures currently used in department of Agricultural Chemistry of TARI, in which one will find his best method depending on the goal of experiment and on the equipments of the laboratory
Discussion on current methods of soil testing and plant analysis used in TARI
No full text土壤速測與植體分析為瞭解土壤肥力狀況及作物營養狀態快速而有效的方法。因應不同的土壤與作物，土壤速測與植體分析方法繁多，更由於農民之需求標準逐日提高，科技之進步，土壤速測與植體分析方法不斷地改進，分析儀器之使用亦由簡單的光度計起發展成今日的高性能儀器（如ICP，AA等），本文就農試所農化系經常使用的土壤速測與植體分析方法簡單的說明和討論，並對未來的發展提出一個瞻望，以供參考。
Soil testing and plant analysis are means of assessing soil fertility and plant nutrient element status which have a considerable history of development and use.
Various procedures have been developed and improved which aims to evaluate the soil fertility and plant nutrient status more precisely. Recent development of multi-elementanalyzers such as inductively-coupled plasma emission spectrometer (ICP) favours the use of multi-element extrcting reagents instead of traditional single element reagents.
This paper describes briefly various procedures currently used in department of Agricultural Chemistry of TARI, in which one will find his best method depending on the goal of experiment and on the equipments of the laboratory
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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