Surface Structure and Thermal Stability of Platinum Group Metallic Nanoparticles with High-Index Facets

铂族金属纳米粒子由于具有优异的催化性能，已被广泛地应用于燃料电池，石油化工，汽车催化转化器等领域。但是，稀缺的资源以及昂贵的价格严重地限制了它们的应用。为了满足工业上日益增长的需求，如何提高它们的催化活性和催化效率就成为了工业催化领域的一个关键问题。高指数晶面纳米粒子的成功合成为解决这一问题提供了一条新的途径。高指数晶面是指密勒指数{hkl}中至少有一个指数大于1的晶面。这类晶面拥有高密度的低配位原子，这些原子分布在具有高活性的催化位点，如台阶、棱边和扭结位。因此，高指数晶面纳米粒子表现出了极大的应用潜力。本文应用分子动力学方法，对高指数晶面铂族金属纳米粒子的结构稳定性和热稳定性进行了系统的研...Platinum-group metallic nanoparticles are widely used as indispensable catalysts in fuel cells, petrochemical reforming and automotive catalytic converters due to their excellent catalytic performance. However, the rare reserve and high cost severely limit its further usage. In order to meet the increasing demand in industry, how to improve the intrinsic catalytic properties and utilization effici...学位：理学博士院系专业：物理科学与技术学院_凝聚态物理学号：1982013015423

China's Cultural Diplomacy with Portuguese-Speaking Countries since 1949:History Review and Challenges

文化外交作为外交的第四个支柱,是对当今国际关系领域中国家、市场与社会三者互动的有效应对,是传统政治、经济、军事外交的有益补充,并与其共同构成我国外交的有机体系。新中国对葡语世界的文化外交有效地提升和拓展了我国的国家利益。面对转型期变化莫测的国际体系,我国对葡语世界的外交政策也面临诸多挑战。只有继续并深化对葡语世界的文化外交,才能在日益重要的葡语世界中维护并强化我国的国家利益。As the fourth pillar of the diplomacy,cultural diplomacy effectively deals with the interactive relations among states,markets and societies in international relations.And it is the useful complement to the conventionnal political,economic and military diplomacy.Cultural diplomacy is based on soft power theory,national image theory,intercultural communication theory,and theory of dialogue-between-civilizations.It will be highlight in China's future diplomacy and will occupy an increasingly important role in China's foreign policy.Since 1949,China's cultural diplomacy has enhanced and expanded China's interests.With the complex and changeable international system in today's transitional period,China has to meet many challenges concerning its foreign policy towards Portuguese-speaking countries.In order to protect and increase its national interests,China should continuously strengthen and improve the cultural diplomacy in the Portuguese-speaking world

H ilbert 空间中g-Parseva l 框架的一些性质

在Hilbert 空间中讨论g-Parseval 框架的一些性质 , 得到g-Parseval 框架约一些恒等式和不等式国家自然科学基金(l 0 5 7 1 1 45 ); 福建省自然科学基金项目(z 0 5 1 1 01 a) 及省教育厅基金项目(J B o 4 O3 8

First-Principles Study of Effect of Strain on the Band Structure of ZnO Monolayer

采用基于密度泛函理论的第一性原理计算对单层znO薄膜能带结构的应变调控进行了研究.计算结果表明:沿着之字形方向的压缩应变和扶椅形方向的拉伸应变对薄膜带隙的调控都是线性的,而且带隙调控的范围最大;相反地,在沿着之字形方向的拉伸应变和扶椅形方向的压缩应变的调控下,带隙则呈现出非线性的变化.对于双轴应变的拉伸与压缩,带隙的变化都是非线性的.这种通过不同的应变加载方式来实现对带隙不同程度的调控,对znO薄膜在光学和催化等领域的应用具有重要的指导意义.The effect of strain on the band structure of the ZnO monolayer has been investigated by firstprinciples calculations based on density functional theory.The results reveal that the band structure of the ZnO monolayer presents different dependences on three types of strain.The band gap linearly and steeply varies under uniaxial zigzag compressive strain and armchair tensile strain, while it shows nonlinear dependence on the other types of strain.Therefore, uniaxial zigzag compressive strain and armchair tensile strain should be the most effective to tune the band gap.This work has significant implications for application of strain to tune the optical and catalytic properties of ZnO nanofilms.国家自然科学基金(10702056;11204252); 四川省教育厅(12ZA072)资助项目~

Comparison between REA model and thin layer drying model based on strip drying kinetics

为了获得最适用于烟草干燥的动力学模型,达到设计、优化和控制烟草干燥过程的目的,采用湿度发生器联用热重技术(TGA)研究了65 ℃ &RH; 15%, 75 ℃ & RH 10%和85℃& RH 5%条件下片烟的干燥动力学行为,并利用REA (Reaction engineering; approach)以及8种经验或半经验的薄层干燥模型分别对不同温湿度条件下的片烟干燥行为进行模拟。结果表明:①干燥温度越高,相对湿度越小时,片烟; 的干燥速率越快,平衡含水率越低;②REA模型预测的片烟干燥动力学曲线与实验曲线能够很好地吻合,尤其是在含水率由20%降至12%阶段;8种薄层干燥; 模型中Two; term模型拟合出的R~2值最大,均方根误差(RMSE)最小,是描述片烟干燥行为较合适的模型;③薄层干燥模型仅仅是获得特定温湿度条件下相对应的动; 力学参数,而REA模型是将温度和湿度作为变量引入模型中,模型中的动力学参数可以描述任意温湿度条件下的片烟干燥动力学行为;④REA模型构造简单,预; 测准确快速,较Two term模型更具有普适性、实用性。In order to select a kinetic model best fit for the design, optimization; and control of tobacco drying process, the drying kinetic behavior of; tobacco strips under the conditions of 65 ℃ & RH 15%, 75 ℃ & RH10%, 85 ℃; & RH 5% was investigated with a humidifier combined with TGA; (Thermogravimetric analyzer). The drying behavior of tobacco strips was; simulated by REA (Reaction engineering approach) model and eight; selected thin layer drying models (semi-empirical or empirical). The; results showed that: 1) With the rise of temperature and decrease of; humidity, the drying rate of strips raised and the equilibrium moisture; content of strips lowered. 2) The drying kinetic curves predicted by REA; model well agreed with experimental curves, especially at the stage when; the moisture content decreased from 20% to 12%. Among eight thin layer; drying models, Two term model was the best for predicting the drying; behavior of strips with the highest R~2 (determination coefficient) and; the lowest RMSE (root mean square error). 3) Thin layer drying model; reflected only the kinetic parameters corresponding to specified drying; conditions, while in the REA model the temperature and humidity served; as variables, it enabled the kinetic parameters in REA model to describe; the drying kinetic behavior at any drying condition. 4) REA model was; simple in structure, fast and accurate in prediction, more universal and; practical than Two term model.福建中烟工业有限公司科技项

负偏置沉积法可控制备CuO多孔纳米结构薄膜

由于具有低成本、无毒、铜源丰富等优点,以及在气敏传感器、太阳能电池、光催化等领域的潜在应用前景,CuO薄膜引起了人们的广泛关注.采用射频平衡磁控溅射镀膜系统,在薄膜沉积过程中通过施加不同衬底负偏压可控制备了CuO多孔纳米结构薄膜.研究发现,所得CuO薄膜具有灵活可调的孔隙度和纳米构筑单元形貌特征,并且它们与衬底负偏压的大小密切相关;薄膜沿衬底法线方向呈柱状生长且具有显著的（111）择优取向;禁带宽度在2.0.35 eV之间可调.很明显地,传统的溅射离子轰击、再溅射理论并不适合用来解释上述负偏压效应,因此在此基础上提出了一种负偏置沉积过程中材料原子或分子在薄膜表面选择性优先沉积机制.国家自然科学基金(51501018,11574255)；江苏省自然科学基金(BK20150267,BK20141169)；江西省教育厅科技项目(GJJ161197)；江西省自然科学基金(20132BAB212005)资助

Controllable fabrication of Cu_2O porous nanostructured films by negative bias deposition method

由于具有低成本、无毒、铜源丰富等优点,以及在气敏传感器、太阳能电池、光催化等领域的潜在应用前景,; Cu_2O薄膜引起了人们的广泛关注.采用射频平衡磁控溅射镀膜系统,在薄膜沉积过程中通过施加不同衬底负偏压可控制备了Cu_2O多孔纳米结构薄膜.研; 究发现,所得Cu_2O薄膜具有灵活可调的孔隙度和纳米构筑单元形貌特征,并且它们与衬底负偏压的大小密切相关;薄膜沿衬底法线方向呈柱状生长且具有显著; 的(111)择优取向;禁带宽度在2.0~2.35; eV之间可调.很明显地,传统的溅射离子轰击、再溅射理论并不适合用来解释上述负偏压效应,因此在此基础上提出了一种负偏置沉积过程中材料原子或分子在薄; 膜表面选择性优先沉积机制.As one of the most common two kinds of copper oxides, cuprous oxide; (Cu_2O) is an important p-type transition metal oxide semiconductor; material. Due to the advantages of low-cost, non-toxicity and abundant; copper sources and the potential applications in the fields of gas; sensors, solar cells and photocatalysts, thin films of Cu_2O have; attracted great interest of researchers. To enhance the performances of; the above Cu_2O-based surface-sensitive devices and materials, the; researchers tend to prepare Cu_2O thin films of porous or even; nanoporous structures. However, there is still no effective method; available for the controllable fabrication of Cu_2O porous; nanostructured films (or porous nanostructure-films, short for PNFs),; which owns not only the common features of porous thin films but also; the unique properties of nanosize building units. By using a; radiofrequency balanced magnetron sputtering (MS) deposition system, in; this paper, Cu_2O PNFs were prepared on clean glass slides by applying; different negative bias voltage during film deposition. After the; preparation, a field-emission scanning electron microscope (FESEM), a; grazing-incidence X-ray diffractometer (GIXRD) and an; ultraviolet-visible (UV-Vis) spectrophotometer were applied subsequently; for the detailed characterizations of surface morphology, texture and; optical property respectively. It was observed that the as-prepared; Cu_2O PNFs exhibited flexible porosities and nanosize building units,; which were greatly dependent on the substrate negative bias voltage. In; particular, when the substrate bias voltage was kept at -50 or -150 V,; the as-prepared Cu_2O PNFs both demonstrated intriguing triangular; pyramid-like nanostructures with distinct edges and corners on the; porous film surface. Further, the side view FESEM images and the; out-of-plane GIXRD spectra demonstrated a columnar growth of the Cu_2O; PNFs with a notable preferential orientation of (111). The optical; testing results showed that the band gap of the Cu_2O PNFs obtained at; different negative bias voltages was tunable between 2.0 and 2.35 eV,; which demonstrated a little red or blue shift relative to that of bulk; Cu_2O (2.17 eV). It is expected that the traditional ion bombardment and; re-sputtering theories are not suitable for the explanation of the above; bias voltage effects. This is because the traditional ion bombardment; and re-sputtering theories were proposed to account for the bias; deposition in an unbalanced magnetron sputtering (MS) system rather than; the present balanced MS system. Further, the experimentally observed; non-linearly changed density or porosity of the Cu_2O PNFs with the bias; voltage at relatively low values and the common even surface at; relatively high values confirmed this viewpoint. Based on the above; findings and analysis, a selectively preferential deposition of material; atoms or molecules on the film surface during the negative bias; deposition was proposed. That is, when the substrate is negatively; biased, the tipcharging effect of electrons would occur on the nanoscale; rough surface of the substrate or the depositing film. The resulting; electric field near the substrate or film surface is non-uniform and; could be regarded as an assembly of many electric fields of particle or; tip charges.国家自然科学基金; 江苏省自然科学基金; 江西省教育厅科技项目; 江西省自然科学基

ヒフ キンエン ノ ハッショウ オ ケイキ ニ シンダン サレタ ショウサイボウ ハイガン ノ 1レイ

74 歳男性.顔面,四肢,体幹の紅斑に続き,構音障害および嚥下障害,四肢筋肉痛並び脱力が出現し,起立困難となり入院となった.CK, ALD, AST, LDH 等筋原性酵素の著明上昇及び臨床所見により皮膚筋炎と診断された.高用量ステロイド療法その後シクロスポリンの追加にて治療開始し,検査所見に続き,臨床所見も改善傾向にあった.同時にproGRP 高値並びに全身CT 画像上縦隔リンパ節腫大認め,気管支鏡下気管支粘膜生検にて小細胞肺癌の病理診断が得られ,CBDCA+CPT-11 にて化学療法を施行,腫瘍の縮小効果を見た.皮膚筋炎が腫瘍随伴症候として,小細胞癌とほぼ同時期に発病したことを示唆した症例であったA 74-year-old man was admitted because of erythemaon face, extremities and trunk, followed by dysarthria, dysphagia,extremity myalgia accompanied with weakness, andthen difficulty in upstanding. Dermatomyositis (DM) wasdiagnosed on the basis of a marked increase in serum levelof myogenic enzymes, such as creatinin kinase, aldolase, aspartateaminotransferase and lactate dehydrogenase, andthe clinical manifestations. Introduction of high-dose glucocorticoidtherapy, subsequently concurrent administrationof cyclosporin, made laboratory data gradually return tonormal and produced slight symptom improvement. Inscreening for malignancies, high level of proGRP detectedin peripheral blood, computed tomography scan showed mediastinallymphadenopathy, and histopathologial testing ofthe transbronchial biopsy specimens revealed small celllung cancer (SCLC). Chemotherapy (CBDCA+CPT-11)started, resulting in tumor reduction. The current case maysuggest that DM coincided with SCLC around at the sametime, as a mean of paraneoplastic syndrome

Adaptive Link Adaptation Algorithm in High Speed Downlink Packet Access (HSDPA) System

在高速下載封包擷取系統中提出了多項相對於全球行動通訊系統的技術改善來提升服務效能 ， 而它之所以能提升封包最大傳輸率達到10Mbps的主要原因在於高速下載封包擷取系統使用的連結調整是適應性調變編碼 ， 適應性調變編碼的功能在於節點B隨著通道情況的變化去選擇不同的調變與編碼組合來傳送封包 ， 如果傳送的封包使用了正確的調變與編碼組合 ， 則不僅生產量會提升、封包錯誤率會減少 ， 還有延遲問題亦會降低 ， 所以調變與編碼組合界線值的選取是一項影響其效能的重要因素 。 最佳化調變與編碼組合界線值的決定主要取決於目前手機用戶的無線通道環境 ， 但因為無線通道環境是隨著時間改變的 ， 所以我們並沒有辦法事先得知在哪種通道環境下的最佳化調變與編碼組合界線值 。 倘若今天手機用戶處於較差的通道環境中 ， 但卻使用了在較好通道環境中的最佳化調變與編碼組合界線值 ， 則它的生產量效能就會降低 ， 反之亦然 。 在這篇論文裡 ， 我們提出了一個利用背景查覺學習基準的方法來解決這個問題 ， 背景查覺的主要概念在於線上的學習通道環境的情況後做適應性的調整調變與編碼組合界線值來達到最佳化 ， 而我們做適應性連結調整的目標在於達到整體生產量的最大值 。 在我們的提出的作法中 ， 首先節點B會先收集從手機用戶回傳的通道環境訊息及封包接收情況的資訊後 ， 再利用類神經網路的概念去學習訊號雜訊比、調變與編碼組合界線值之間的複雜非線性封閉形式 ， 在獲得這個非線性的封閉型式後 ， 我們利用它來產生在某段訊號雜訊比區間內的累加生產量 ， 再來我們同樣利用類神經網路的概念去學習累加生產量和調變與編碼組合界線值之間的複雜非線性封閉型式 ， 而在獲得這個非線性封閉型式後 ， 我們可以根據累加生產量跟未調整前的調變與編碼組合界線值之間的梯度關係來做適應性的調整調變與編碼組合界線值達到最佳化的值 。 這篇論文的貢獻在於我們提出了一個在隨著時間改變的通道環境中做適應性的調整調變與編碼組合界線值達到最佳化值的方法 ， 進而達到生產量的最大值 。 模擬的結果證實了我們所提出的方法可以處理隨著時間改變的通道環境所造成的問題 ， 並且提昇了生產量 。In HSDPA system, a set of enhanced technique have been proposed to improve the service performance in proportion to the UMTS (Universal Mobile Telecommunication System), and the primary reason that HSDPA could improve the peak rate of packet transmission up to 10Mbps is that the HSDPA utilize the AMC (Adaptive Modulation and Coding) as its link adaptation. The function of AMC is that Node B selects the variable MCSs (Modulation and Coding Schemes) to transmit the packet according to the changed channel conditions, if the packet transmits with the correct MCS then it will come out with a consequence that the throughput will be upgraded and the packet error rate and the delay requirement will be degraded, so the threshold of the MCSs is one of the most important factors that would affect the performance in HSDPA system. The optimal threshold depends on the user’s wireless channel environments. However, the channel condition is time-varying and it is difficult to decide optimal threshold in advance. If the user is in the worse channel condition but utilizes the thresholds suited to the better channel condition, then its throughput will be degraded, vice versa. In this thesis, we tackle this problem by a context-aware learning-based optimization approach. A context-aware framework is designed to learn the channel conditions on-line and optimize the threshold adaptively with the goal to maximize the overall throughput. In our approach, first, the node B collects the knowledge of the channel conditions and the information of the packet successful received or not those are feedback from users and uses these obtained knowledge and the capability of neural networks to learn the complex nonlinear function among the throughput, the threshold and the SNR (signal to noise rations), after acquiring the complex nonlinear function, we take advantage of it to get the aggregated throughput in certain SNR region. Then we use the capability of the neural network again to learn the complex nonlinear function between the aggregated throughput and the threshold and adjust the threshold adaptively to reach an optimal value according to the gradient which is derived from the aggregated throughput and the threshold. The contribution of this thesis is that we propose an approach that is applicable to the real situations to adaptively regulate the threshold to reach the optimal value and maximize the overall throughputs. The simulation results show that our approach can deal with the time-varying wireless channel conditions and improve the throughputs.摘要..........................................................................................................Ⅰ Abstract.....................................................................................................Ⅲ 致謝..........................................................................................................Ⅴ Acknowledge.............................................................................................Ⅵ 1. 簡介.......................................................................................................1 1.1 行動通訊發展的演變.................................................................................1 1.2 寬頻分碼多工存取(W-CDMA)................................................................4 1.2.1 第三代行動通訊的簡介......................................................................4 1.2.1.1 第三代行動通訊頻譜的配置.....................................................4 1.2.1.2 第三代行動通訊的空氣媒介...................................................6 1.2.2 全球行動通訊系統(UMTS) ..............................................................6 1.2.3 全球行動通訊系統的架構.................................................................8 1.2.3.1 使用者裝置(UE)............................................................................8 1.2.3.2 全球行動通訊系統地面無線存取網路(UTRAN)...............8 1.2.3.3 核心網路(Core Network).............................................................9 1.2.3.4 外部網路(External Network)...................................................10 1.2.3.5 介面(Interface)..............................................................................11 1.2.4 全球行動通訊系統協定架構..........................................................12 1.2.4.1無線電資源控制協定(RRC).....................................................12 1.2.4.2封包資料整合協定(PDCP)........................................................12 1.2.4.3 廣播與多重傳送控制協定(BMC)..........................................13 1.2.4.4 無線電連結控制協定(RLC)....................................................13 1.2.4.5 媒體存取控制協定(MAC).......................................................13 1.2.4.6 實體層(PHY)................................................................................14 1.2.4.7邏輯、傳輸與實體通道................................................................15 1.2.5 全球行動通訊系統的缺點...............................................................17 1.3 高速下載封包擷取(HSDPA)..................................................................19 1.3.1 新的傳輸通道......................................................................................19 1.3.1.1 高速下載共享通道(HS-DSCH)..............................................20 1.3.1.2 高速共享控制通道(HS-SCCH)..............................................22 1.3.1.3 上傳專有實體控制通道(Uplink DPCCH)...........................23 1.3.2 高速下載封包擷取協定架構..........................................................24 1.3.3 適應性調變編碼(AMC)....................................................................25 1.3.4 混合自動重複要求(HARQ)............................................................28 1.3.5 快速排序(FS).......................................................................................32 1.3.6 快速細胞選取(FCS)..........................................................................36 1.4 論文研究的目的.........................................................................................38 2. 適應性連結調整最佳化的問題與相關研究...........................................39 2.1 適應性調變編碼可能發生的問題........................................................39 2.2 相關研究.......................................................................................................43 2.2.1 界線調整演算法(TAA)….................................................................43 2.2.2 在界線值附近區間內 作界線值調整演算法................46 3. 提出的研究........................................................................................................48 3.1 成本報酬方式.............................................................................................48 3.2 類神經網路與倒傳遞演算法.................................................................53 3.2.1 類神經網路架構.................................................................................53 3.2.2 倒傳遞演算法......................................................................................55 3.3 提出的架構..................................................................................................61 3.4 實用性的考量.............................................................................................67 4. 模擬結果............................................................................................................69 4.1 初始界線值的調整....................................................................................69 4.2 在改變的通道環境中做適應性的界線值調整.................................84 4.3 提出的方法的生產量效能.....................................................................90 5. 結論......................................................................................................................98 參考文獻.................................................................................................................. 9