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舊桌第二春-力學探討學生舊桌結構補強與置物空間優化設計
利用自然課程力學原理,進行廢棄舊桌進行結構補強,增加桌子放置物品空間,自製剪力實驗台檢測桌子補強後結構強度,自製振動模擬器檢測桌子搖動程度,實驗結果如下: (一)現在使用新式桌子有結構上的問題:榫接太小、前櫃板未與前柱榫接,形成前側結構強度 弱點,因此桌子容易搖動,大約80%要補強。 (二)將新式桌子設計瑕疵部分進行結構補後,左右方向傾角降低88.5%,前後向降低67.5%。補強後新式桌子桌比新式新桌搖動位移小,桌子結構補強後強度更高。 (三)置物空間增加2.14倍,快速安裝高度調整器降低,將12型桌子簡化到4型。 (四)製作一副桌椅碳足跡為21.69公斤CO2。延長使用年限,降低木材使用量,對於氣候變遷與環境有正面價值。
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Development and Comparison of a Small-Scale Toroidal Horizontal-Axis Wind Turbine to a Conventional HAWT Design
Wind energy is one of the most promising and rapidly growing sources of renewable energy, although maximizing its efficiency while minimizing noise remains a challenge and limits its widespread adoption. The emergence of toroidal propellers, which have gained popularity for producing comparable thrust levels to traditional drone propellers while producing less noise, could mitigate this. This study aimed to develop a small-scale toroidal HAWT and compare its power and noise output to a conventional rotor design under similar wind velocity conditions. 15-centimeter diameter models of the toroidal and conventional rotors were created in Fusion 360 and simulated using Ansys Fluent to identify the significant aerodynamic characteristics that positively affect the blades’ power coefficient. The toroidal design with the greatest simulated power output at low tip speed ratios (TSRs) was then 3D printed and physically tested in a wind tunnel against the control rotor. The experimental results confirmed that the toroidal design had greater power coefficients at lower TSRs compared to the control rotor. The toroidal rotor started operating at a wind velocity of 3 m/s compared to the control rotor’s 6 m/s, which indicates superior start-up characteristics. While the toroidal rotor produced half the power output of the control at the highest tested wind speed of 7 m/s, it emitted 18 decibels less noise and showed a reduction in discernible noise between frequencies of two to five kilohertz. The results from this study show its potential in low-noise wind turbines within low-wind velocity environments.
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Straw manufacturing for epidemic prevention
Recently,thefeedpricesforlivestockfarmshavebeencontinuouslyincreasing, while the prices of calves have been declining, leading to many livestock and dairy farms facing financial losses. If livestock farms are affected by diseases such as foot-and-mouth disease, they suffer significant losses. This is because reducedproductivityinlivestocknotonlyaffectstheirproductionbutalsoentails substantial costs for vaccines and treatments. Therefore, there is a need to explore how to effectively prevent diseases, focusing on common diseases in cattle such as subclinical mastitis and mastitis, and alleviate the burden on farms economically and environmentally. This study aims to investigate the production of bacterial growth-inhibiting straw bedding using substances such as illite and charcoal to contribute to disease prevention.
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法拉第波輔助合成奈米鎳並應用於有機污染物的快速脫色
Nanostructured Nickel Synthesized through Faraday Waves and Its Application to Rapid Contaminants Decolorization
超音波已廣泛用於奈米粒子的製備,然可聽聞音對奈米粒子製備的影響卻少有研究。本研究以簡易喇叭裝置產生可聽聞音並在溶液表面產生法拉第波及內部流動,來輔助製備奈米鎳。法拉第波是一種表面非線性駐波,透過調整容器形狀、振動頻率等,可產生不同波形。本研究嘗試在法拉第波輔助下,以化學還原法及電沉積法製備出不同性質的奈米粒子。SEM量測並比較無輔助、法拉第波輔助、超音波輔助製備出的奈米鎳的形貌、分布的差異。並將其應用於有機物(即剛果紅、亞甲藍、4-硝基苯酚、2-硝基苯酚)之催化還原。而由SEM量測、催化還原結果及理論模擬反應熱可知,法拉第波確實能夠改善奈米鎳的粒徑大小、分散性、對氫的吸附能力及催化還原能力。
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Most people in the country tend to consume soda as part of their daily lives, without thinking about the health consequences that this entails. And the fact is that 墨西哥 is considered the main consumer of soda in the world (Universidad Nacional Autónoma de México [UNAM], 2019), and not only that, it also tops the lists of obesity and diabetes (Procuraduría Federal del Consumidor [PROFECO], 2018). A bad diet is one of the main causes of these medical conditions, so it is necessary to rethink the foods of daily consumption. In this project, the development of a carbonated beverage with three main ingredients: purple corn, hibiscus, and pineapple, which contain diverse nutritional properties in addition to having significant amounts of antioxidants (Secretaría de Cultura,2020; Sumaya et al., 2014; Kongsuwan et al., 2009), is established as an objective. In addition, antioxidants act as regulators of cellular aging and prevent chronic diseases (Vilaplana, 2007). For this reason, the elaboration of a beverage with these characteristics is considered harmless and a good option for people with a chronic disease or who are prone to it, as well as a healthy alternative to the consumption of soft drinks. In this project, an experimental methodology was followed to prepare the nutritional beverage, which had nutritional properties, such as vitamin and antioxidant content, in addition to having a pleasant taste and texture.
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我們以實驗室及生活上容易取得的重物與乒乓球模擬網路上跳水彈射手中球體的沃辛頓射流實驗。結果發現以圓形的類天然海棉托住乒乓球丟入水中可成功產生射流,因此選擇此為托球的載體進行實驗。依據我們的實驗結果,至少需要15公分水深才能形成完整的射流彈射出乒乓球,原則上在下落軌跡完全垂直於水面時,落下高度越高,球體彈射高度越高,實際實驗水深15公分以上時,落下高度50公分彈射高度約可達47公分,但結果受限於托球的海綿在落下高度40公分後下落軌跡不穩定,若期望更高的射流強度需要尋找更穩定下落的載體。最後我們將實驗影片逐格分析計算,證實球體彈射過程是一個反覆受到重力及空氣阻力等因素影響降速,又受到下方射流水柱力量推擠而加速的過程,初步建立以乒乓球標示射流噴射過程運動模式的邏輯。
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Non-Invasive Vagus Nerve Stimulation as a Novel Therapy for Alzheimer’s Disease by Enhancing the Brain Clearance System(非侵入性迷走神經刺激術作為阿茲海默症的新療法—透過增強大腦清除系統)
阿茲海默症(AD)是導致失智症的主因,影響全球數千萬人。然而,AD目前的藥物大多昂貴且療效有限。目前已知腦內β類澱粉蛋白(Aβ)斑塊為AD的病理特徵,且大腦清除系統被認為對AD的治療具有重要性。先前研究發現非侵入性迷走神經刺激術(nVNS)增加腦脊髓液循環,但在神經退化疾病中的機制和應用尚不明確。本研究旨在探討nVNS增強大腦清除系統來作為AD新療法之成效,使用Aβ誘導之AD小鼠模型,利用巨視顯微鏡和免疫組織化學染色評估其膠淋巴系統功能,並以新奇事物測試評估認知功能。本研究發現於AD小鼠中,給予nVNS使大腦清除系統之水通道蛋白-4顯著增加、促進膠淋巴系統,進而改善認知功能。本研究首次發現nVNS可通過增強大腦清除系統功能,進而改善AD病理引起的失智症狀,支持nVNS作為AD新療法的可行性。
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利用 Verapamil 引發斑馬魚胚胎心衰竭模式並探討臨床心衰竭用藥 Dapagliflozin 和 Valsartan 之成效與機制
本研究利用 Verapamil 誘導斑馬魚胚胎心衰竭模式,並探討 Dapagliflozin 對斑馬魚胚胎表皮離子細胞的調控機制,以加深對 SGLT2 inhibitors 機制的了解。受精後第四天的斑馬魚在暴露於Verapamil 24小時後,除了抑制卵黃囊吸收以及造成心包膜水腫以外,對心臟整體功能(HR, EDV,ESV, SV, EF, CO)具負面影響。以粒線體染劑標記離子細胞,發現Verapamil使其密度上升,使用掃描式電子顯微鏡觀察,則可看到離子細胞頂端開口有明顯的萎縮,影響到正常功能。以抗體標記染色的方式檢測不同離子細胞亞型,顯示 Dapagliflozin 使富含 Na⁺-K⁺ ATPase 的 HR 細胞和富含 H⁺-ATPase 的 NaR 細胞密度上升。同時,心臟功能診斷標誌物的 mRNA 水平(naap, nppb,gata4, vmhc)暴露於Verapamil後上升,促進離子細胞代償性上調。
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直笛是每位學生必學樂器,加上簧片巧思,創作出簧片直笛。實驗變因控制為形狀(三角形、梯形、長方形),厚度以及材質。運用問題解決,開發出雷射切割簧片及板擦機吹氣,將人為誤差去除。實驗發現,三角形簧片會將頻率往上移動,上升最大59.2%。梯形簧片,當簧片寬度越寬,振動頻率越低。長方形簧片,簧片長度越長,振動頻率越高。當厚度越厚,頻率會變低。不同材質簧片,發現投影片簧片頻率變化最佳。從共振分析得知,當簧片振動頻率接近笛子自然頻率,音量增加。當簧片振動頻率沒有接近笛子自然頻率時,無法發出聲音。原本學生常用的高音笛,配合簧片替換創新,可吹出超高音笛的聲音。「笛管新聲可創造出不同音域的巧妙變化」。
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消氨×植碳:比較養殖水與自來水對氮循環與空心菜固碳效益的影響
本研究探討「養水」過程水質穩定的重要性,再以養水組、自來水組為實驗及對照,分別觀察水中氨氮、亞硝酸鹽與硝酸鹽濃度變化,驗證硝化作用是否自然發生。結果,靜置兩週能有效培養硝化菌,建立氮循環。當硝化菌大量生成後,水質會突然呈現清澈狀,若穩定度被破壞之後,還需要12天才能達成平衡。 再探討「養殖水」利用在種植上,可促進植物生長並兼具氮循環與碳固定功能。我們分別比較養殖水組的空心菜長度、重量與碳含量均優於自來水組,推估吸收二氧化碳量提升超過20%。本系統證明魚類排泄物可轉化為植物養分,創造「消氨×植碳」雙效益,實踐水資源再利用與碳固定目標,呼應聯合國SDGs中(目標6、13),展現簡單可行又具永續價值的水耕共生系統。
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一群運動員在一條直線跑道上,以互不相同的均速做折返跑。當這群運動員於某一時刻全部相遇於某一點後,這樣的情形會不會再度發生?我們找出這群運動員第一次相遇和再次相遇的的條件及相遇點,並延伸探討圓形跑道相遇的情形,最後討論給定k名運動員的速率比,判斷其是否會相遇。
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生活中小蘇打與檸檬酸都是很棒的清潔利器 , 各種發泡錠更是利用酸鹼中和的特性所製造出的物品,許多人用此性質自製屬於自己的各式發泡錠。我們從二氧化碳產生量、溶解、硬度、清潔、防黴的角度思考。經研究發現,五種比例清潔錠中小蘇打和檸檬酸的配製比例,以2:1製作最好,它在清潔、防黴都有較好效果。想要增加硬度,可以添加玉米粉。想要強化防黴效果,可以再添加薑黃。想省錢,可以用鹽代替薑黃製作清潔錠。
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