31,688 research outputs found
The political role of the people's liberation army 1949-1973
Full text linkThis thesis is to study the political role of the People's Liberation Army from the approach of structure and function. The framework of the thesis consists of three major parts, first, the influence of Chinese traditional political culture on, and the formation of, the political role of the PL A; second, the influence of domestic political struggles and external military conflicts on the development of the political role of the PLA; and the third, the analysis of the transition of the PLA's political role from the structure and personnel arrangements of the CCPCC Within the above-mentioned three scopes, this thesis make a thorough discussion on the following: (1) The relationship between the structure of the PRC and the formation of the PLA's political role; (2) How has ideology influenced the army's political role; (3) What is Mao's viewpoint and his influence on the development of the army's political role; (4) What is the link between the army and the party, and how has this developed; (6) What accounts for the expansion of the PLA's political functions; (7) What is the influence of political factional struggles on the PLA's political role; (8) Is it political institution or military institution that controls the recruitment of the military elite; (9) What are the disparities between the military elite in handling international conflicts and what are their political considerations; (10) What is the Party's position in the army; (11) How have the Party’s important meetings and personnel arrangements influenced the rise and fall of the PLA's political role
Visible-light response Cr-doped TiO2-XNX photocatalysts
No full textChromium (Cr) and nitrogen (N)-doped titania (TiO2) was prepared using sol–gel method and ammonia thermal treatment. TiO2 co-doped
with Cr and N showed intense absorption bands in the visible-light region. The X-ray photoelectron spectroscopy (XPS) detected chromium
and nitrogen ions on the surface of catalysts, but no diffractive peak of chromium oxide or titanium nitride was observed in X-ray diffraction
(XRD) spectra. The analysis of X-ray absorption near edge spectroscopy (XANES) indicated either Cr3+ or Cr4+ chemical status implying that
chromium either substituted Ti4+ site or locally was isolated on the surface of TiO2. The photocatalytic activity was evaluated by the degradation
of methylene blue (MB) and isopropyl alcohol (IPA) under visible-light (>460 nm) irradiation using blue-light emitted diode. The rate constants
of MB and IPA photodegradation with N-doped TiO2 were 7.7 and 80 mol l−1 h−1 g−1, which were much higher than those with pure TiO2, 0.15
and 0 mol l−1 h−1 g−1, respectively. The Cr and N co-doped TiO2 showed less photoactivity than either Cr or N-doped TiO2 due to the extra
imperfection of TiO2 lattice during preparation
Visible-Light Cr-doped TiO2-XNX Nano Photocatalysts
No full text為了能夠更有效率的利用太陽光或是室內光源，本研究致力於研發具有可見光應答催化活性之二氧化鈦光觸媒。利用改良式溶膠凝膠法合成二氧化鈦，並且在製程中摻雜鉻、氮元素。相較未經改質之本質二氧化鈦以及商用觸媒P25，摻質後的二氧化鈦成功的具備吸收波長小於550nm之可見光的能力，並且能夠有效的催化亞甲基藍染料水溶液的還原脫色反應、以及異丙醇水溶液的氧化分解反應。在亞甲基藍及異丙醇的催化反應中，改質觸媒在可見光下之反應速率常數分別為9、0.8(μmole/liter-hr-g)；比起純二氧化鈦1.1、0(μmole/liter-hr-g)皆高出許多。
在二氧化鈦中摻入鉻元素的改質製程，使價態與傳導帶間形成其他的獨立能階，進而降低電子電洞對分離所需激發光子之能量，始能達到改質可見光應答目的。而過量摻雜之鉻元素則會進入結構中的鑲嵌位置，扭曲本質結構的結果會造成二氧化鈦原本具有之良好光量子效益降低。
對二氧化鈦進行氨氣熱處理則能將氮原子取代結構中氧原子並生成微量氮化鈦成分，氮原子進入結構中取代位置能夠縮小能隙使得二氧化鈦具有可見光應答催化能力。氮元素摻入量超過最適值後亦會降低光量子效益，推論過量的氮元素摻雜位置、或是還原性氣氛下在結構中引入的氧缺陷會成為光觸媒中降低催化能力的電子電洞再結合中心。To use solar or interior light efficiently, we sought a photocatalyst titania with high reactivity under visible light. Titania powders were prepared and doped into chromium or nitrogen atoms via modified sol-gel method. Doped titania have revealed an improvement over pure titania or Degussa P25 photocatalys under visible light(wavelength<550nm) in UV-Vis absorption and photocatalytic activity such as photodegradations of methylene blue and isopropyl alcohol. The rate constants of MB and IPA catalytic reaction with doped titania are 9 and 0.8(μmole/liter-hr-g), which are much higher than those with pure titania, 1.1 and 0(μmole/liter-hr-g), respectively.
Chromium doped into the lattice of titania is responsible for the visible-light response photocatalytic activity because of the isolated narrow bands formed between the valence band and conduction band and lowering the photon energy required to excite the electrons. However excess doped chromium located the interstitial cites in the lattice distorted the original structure and consequently deteriorated the intrinsic photocatalytic activity of titania.
A few amount of nitrogen atoms substituted the lattice oxygen atom and titanium nitride was formed under ammonia-annealing process. Nitrogen doped into substitutional sites of titania has proven to be indispensable for band-gap narrowing and photocatalytic activity. Increasing the nitrogen-doped concentration more than optimum level lowered the quantum yields, indicating the doping sites and oxygen vacancy introduced under the reductive atmosphere could also serve as electron-hole recombination sites.誌謝
中文摘要 Ⅰ
英文摘要 Ⅱ
目錄 Ⅲ
表目錄 Ⅴ
圖目錄 Ⅵ
第一章 緒論 1
第二章 文獻回顧 2
2-1二氧化鈦簡介 2
2-2光催化反應原理 5
2-3 二氧化鈦可見應答之提升 8
第三章 實驗方法
3-1 TiO2觸媒之合成 20
3-1-1 藥品與儀器 21
3-1-2 Cr/TiO2之製備 21
3-1-3 TiO2-XNX之製備 22
3-1-4 Cr/TiO2-XNX之製備 22
3-2物性分析 26
3-2-1 儀器型號與規格 26
3-2-2 X光繞射法(XRD) 26
3-2-3 紫外-可見光吸收光譜(UV-Visible spectrophotometer)28
3-2-4 X射線光電子譜儀(X-ray photoelectron,XPS) 29
3-2-5氮氣吸附-脫附測定孔徑分佈與比表面積 32
3-2-6 X光吸收光譜術(X-ray absorption spectroscopy,XAS) 33
3-3 光催化活性檢測 36
3-3-1反應物及反應系統相關裝置 36
3-3-2 亞甲基藍（MB）脫色之光催化活性試驗 37
3-3-3 異丙醇（IPA）氧化之光催化活性試驗 41
第四章 實驗結果 43
4-1二氧化鈦之物性分析 43
4-1-1 XRD分析 43
4-1-2 UV-VIS吸收光譜分析 51
4-1-3比表面積與孔徑分析 57
4-1-4結構元素氧化價態分析 60
4-1-4-1 Cr/TiO2系列試樣之光電子能譜分析 61
4-1-4-2 TiO2-XNX系列試樣之光電子能譜分析 66
4-1-5 X光吸收光譜分析 70
4-1-5-1 Cr/TiO2系列試樣之XAS分析 71
4-1-5-2 TiO2-XNX系列試樣之XAS分析 75
4-2二氧化鈦光催化活性檢測 78
4-2-1 Methylene blue（MB）脫色反應 79
4-2-1-1以可見光反應器進行MB脫色反應 81
4-2-1-2以紫外光反應器進行MB脫色反應 87
4-2-2 Isopropyl alcohol（IPA）氧化分解反應 90
4-2-2-1以可見光反應器進行IPA氧化分解反應 93
4-2-2-2以紫外光反應器進行IPA氧化分解反應 95
第五章 結論與建 議 98
5-1 經Cr、N元素摻雜之二氧化鈦結構性質探討 98
5-2 光催化活性分析研究 100
5-3 結論與未來展望 104
參考文獻 106
個人小傳 11
Temporal changes in cytokine/chemokine profiles and pulmonary involvement in severe acute respiratory syndrome
No full text
A Study of Galvanic Electrochemical Etch Stop in Single Crystal Silicon
No full textThe main purpose of this thesis is to study on Galvanic electrochemical etch stop using Au/Si/TMAH formation and tries to find out the conditions that we make micro-structure should need.
Through the formation of Au/Si/TMAH, the wafer which have PN junction etch in TMAH, P type Si would be etched and N type Si would be protected. This mechanism improves the following problem\uef\ubc(1) the stress problem that due to the heavily boron-doped etch stop; (2) the non-batch fabrication and thermal stress problem that electrochemical etch stop have to use external bias and holder protection.
We use TMAH as an etchant. Its advantages are\uef\ubc(1) compatible with the COMS process, (2)adding the specific additive that can increase the selectivity of aluminum, even non-etch. The application of this research will be more elasticity.
Finally, for testing and verifying the feasibility of the parameters, author applied the designing conditions to fabricate the beam structure
Protective effect of Monascus-fermented red mold rice against alcoholic liver disease by attenuating oxidative stress, inflammatory response.
No full textFabrication of Integrated Nebulizer Nozzle Plate Utlizing Micro-molding for FD- ESI Mass Spectrometry
No full textThis study presents a novel concept to integrated nebulizer nozzle plate for FD-ESI (Fused-droplet Electrospary Ionization Mass Spectrometry) using modified LIGA process. This fabrication technique can reduce the production cost of current nozzle plate. It comprises of multi-exposure and single develop (MESD) process, the extra-hard Ni-Co (Nickel-Cobalt) electroforming and thin-wall plastic microinjection molding. The template of nozzle plate is patterned using dry film and MESD process. Later, the template is transferred into metal Ni-Co mold by electroplating. In this study, the technique of extra-hard Ni-Co alloy electroplating process with Hardness of Vickers over (HV) 550 is developed. Then with the stiffness of Ni-Co mold, it can withstand high injection speed. Thin-wall microinjection molding process with short cycle time to fabricate nozzle plate can be finished. Liquid crystal polymer (LCP) is used for thin-wall microinjection molding process. In order to make efficiently atomization, we used ANSYS to optimize PZT actuator. Besides, the work of nebulizer with FD-ESI was demonstrated in this study. a novel design of nozzle plate
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