2,117 research outputs found
Random lasing in the composites consisting of photonic crystals and semiconductor nanowires
No full textLetter from T.T. Richards to Thomas Lamb Eliot
No full texthttps://rdc.reed.edu/v1/resources/692f01b5-3181-48ab-b448-088b2b74ffc3/thumb/128.jpgLetter explaining that the author mailed a copy of the "History of the Halleck Guard" to Thomas Lamb Eliot
(13(4):57-69)INSECTICIDES POLLUTION OF WATER RESOURCES AT CHITU, TAIPEI, TAIWAN
No full textI 五豐化工廠內所設A、B兩化水池中並無高鹼度物質存在，又該二池中之水有緩慢滲入且其農藥成分並有積聚於土中之情形。土坑接受雨水過多，造成廢水流失之機會。此等問題均應予以注意並改進。
II 五豐化工廠附近基隆河之河水中，確有被農藥所污染之情形，該染污河水之農藥以parathion居多，（在282個河水樣本中，有148個被parathion所污染），endrin較少，僅有6次。
在各取樣地點之河水被parathion所污染之程度依次排列為：在工廠下游所中抽取樣本其携有parathion成分之河水佔抽出樣本之68.9%；水廠入水口處佔66.7%；工廠上游佔50%；六堵基隆河與北基公路匯合處較少但亦達22.6%。
民國51年8月間，五豐化工廠為防止廠內農藥外流，曾作多種措施及改進：(l）排水溝加蓋，以防止雨水沖入化水池內。（2）機器漏藥部分修理。故在8月下旬以後，河水被農藥所污染之次數雖因降雨量之激增而未見減少，但河水被農藥所污染之程度則大為減低。雖然如此但仍不能保證該地區河水之絕對安全。該廠乃於53年12月間，興建一立體式完全與外界隔離之化水池。此化水池包括自然蒸發，化毒及貯水三個部分，此池建妥後對該廠廢水之處理，當有進一步之改進。惟目前本省農藥之使用量甚多，因而河水被農藥所污染之機會亦很多，故若事實上不困難，在水廠內設一永久性之遺毒檢驗室，對各該地區河水中之農藥遺量予以不斷之監視為所必須。
During the past fifteen years, organic pesticides have been produced, formulated and widely used here in Taiwan, so that water pollution by pesticides in water resources has become a problem and drawn the attention of the public.
A new industrial area at Liutu (六堵) near Taipei city was established and a water works had been set up at Chitu (七堵) for municipal purposes and to serve this area. The water in keelung river is the raw water source for the water works. Within this new industrial area a pesticides factory, Wofoun Chemical Corporation, is located approximately one mile upstream from the water works, raising the question of water contamination and suitable control measures.
Several investigations were made between April and December of 1962. Samples were taken and tested at various points, various depths within a three to seven days period. For the purposes of the study on insecticide wastes originating from the Wofoun factory and the amount of insecticide concentrations at the intake of the water works, sites and the depths of the sampes taken were changed from September 11, 1962 on as shown in the table.
Parathion, diazinon and endrin were the insecticides to be detected in this in-vestigation, because these were the products formulated during that period of time by the Wofoun factory.
Paper chromatography and bioassay were employed for the qualitative and quantitative detections respectively. Method and test animals used in bioassay were varied in accordance with the sensitivity of the various organisms to these com-pounds. For example, aqueous suspension exposure method with Guppy (Lebistes reticulatus) was used for encirin; first instar mosquito larvae (Culex fatigans) for parathion; and the extraction dryfilm method with three day old house flies (Musca domestica) for diazinon. In the paper chromatography method, in cases when two or more spots appeared, further tests were conducted. Methods for further detec-tion were the Averell-Norris colorimetric method for parathion; the Togo-Powsky method for diazinon and the Phenyl Azide method for endrin.
The dissolved oxygen content and pH values of samples were checked. In addition, the insecticide residues in soil were also examined and follow the same steps as mentioned above.
The results are showed below:
The dissolved oxygen content and pH in the sewage pool were all pretty low, Which indicated that the wastes usually stored in the pool for quite a period of time, and without mixing, but that there are no active alkaline detoxifying substances remaining in the pool. On the other hand, since there is neither Cover over the pool nor on the connecting channel the excess of products eliminated in manufacturing were easily spilt or overfldwed from the pool during the rainy season and this is partly the cause of water pollution by insecticides at the Chitu water works.
The water oozing from leaks in the side wall of Wofoun factory on rainy days also contained a certain amount of insecticides. From the results of insecticide residue analyses, parathion and endrin were found in the soil either around the sewage pool or under the leaks outside the Wofoun factory (see table 3). Those residues may be due to accumulations from the water sewage.
The water in Keelung River was also polluted by insecticides from the Wofoun factory sometimes, depending upon the kind of products manufactured and the rainfall at the time. Among the samples of pollution, 148 out of 282 samples from Keelong River showed the presence of parathion. Only 6 out of 282 samples yielded endrin and 12 out of 122 samples contained diazinon.
In the Keelung River below the factory, the concentration of pollution varied directly with the distance from the factory. At the intake of the water works 66.7% of the samples and even at Liutu (many miles away from the factory) 22.6% of the samples contained insecticide. Due to peculiar currents and backflow about 50% of the samples taken just upstream of the factory were also contaminated by insecticides.
Suggestions were made to the Wofoun Chemical Corporation and the necessary steps have been taken to avoid contamination in the future
Book Reviews of Lin, Y.-L.: Mesoscale Dynamics
No full textBuchbesprechung Lin, Y.-L., 2007: Mesoscale Dynamic
Op welke wyse word die waarheid gelieg? Die kortverhale van T.T. Cloete
Full text linkTruthful lying in T.T. Cloete’s short stories
In this article an attempt is made to characterize the short stories of T.T. Cloete in Die waarheid gelieg. The theory of focalization is examined briefly and a definition of focalization which emphasizes the epistemological aspects ofperspective and formulation is used to examine the stories. The stories are compared to stories of Kafka and Borges indicating the resemblances, especially the fascination with the unexpected and weird contradictions in reality, as well as the differences. An intratextual reading of the stories and poems by the same author is undertaken in an attempt to formulate the epistemic position of the focalization in the texts. The article concludes that the Christian worldview as well as a poetics of nomenliterature of the abstract author can be deduced from the stories on account of the assumption that epistemic stances are reflected in the narrative representation and can be communicated to readers by means of propositional attitudes
Methanol synthese
No full textDocument(en) uit de collectie Chemische ProcestechnologieDelftChemTechApplied Science
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