Density Functional Theoretical Study on SERS Chemical Enhancement Mechanism of 4-Mercaptopyridine Adsorbed on Silver

基于密度泛函理论计算和拉曼光谱理论分析,我们研究了对巯基吡啶(4MPY)分子的拉曼光谱和其在银上的表面增强拉曼光谱(SERS),并进一步探讨了S; ERS与界面吸附结构、异构化、质子化和氢键作用以及低能激发态的关系。首先,我们对两种分子异构体的相对稳定性和拉曼光谱进行了理论分析。在此基础上,; 进而研究了该分子与不同银簇作用时的拉曼光谱,结果表明,4MPY以巯基硫与银簇作用形成强的Ag-; S键,导致拉曼光谱的线型不依赖于所选银簇的大小。接着我们考虑了吡啶氮端作用的两种情况。(1)当4MPY-银簇复合物同时以吡啶氮与水簇或水合质子簇; 形成氢键时,结果表明吡啶环的部分振动频率随氢键和质子化发生蓝移。(2)当考虑吡啶氮与银簇作用时,吡啶环三角畸变振动发生蓝移。上述情况不仅解释了实; 验观测的振动频率变化,而且表明了化学环境改变对相对拉曼强度的影响。最后,我们计算了当对巯基吡啶分子以单端或双端与银簇作用,在考虑激发光与低能激发; 态的能量匹配时,拉曼光谱强度与低能激发态的关系。计算结果表明,在双端吸附构型下,与吡啶氮成键的银簇受激发产生电荷转移态,不仅导致吡啶环v_(12; )、 v_1和v_(8a)振动的拉曼信号增强,而且选择性地增强吡啶环C-H面内对称弯曲振动v_(9a)的拉曼信号。Surface-enhanced Raman spectroscopy (SERS) is one of the most powerful techniques for obtaining fingerprint information on molecules adsorbed on coinage metal surfaces. Its detection sensitivity has reached the single-molecule level. On the basis of density functional theoretical (DFT) calculations and Raman scattering theory, we investigated the normal Raman spectra of two isomers and surface-enhanced Raman scattering (SERS) spectra of 4-mercaptopyridine (4MPY) adsorbed on silver. The results aided us in uncovering the relationships between normal Raman spectra and SERS spectra and adsorption configuration, tautomerization, protonation, and hydrogen bonding interactions as well as low-lying excited states. First, we compared the relative stability and normal Raman spectra of two isomers of 4MPY in the gas phase and aqueous solution with a solvent model similar to the solvation model of density (SMD). We then studied the Raman spectra of 4MPY interacting with silver clusters. Our results indicate that the Raman spectra were not dependent on the size of the silver clusters, owing to the formation of strong Ag-S bonds. We also considered two cases of N-end interaction in the 4MPY-Ag-5 complex. (1) For the hydrogen bond interaction between the nitrogen in 4MPY and water clusters or hydrated proton clusters, the theoretical results indicated that the vibrational frequencies of the pyridine ring increase. (2) For the interaction of the 4MPY-Ag-5 complex with a silver cluster Ag-4 through the lone-paired orbital in nitrogen of the pyridine ring, the theoretical results further revealed that the vibrational frequency shift is in good agreement with SERS peaks reported in the literature. Finally, our calculated results focused on the relationship between the Raman spectra and the charge transfer mechanism when the excitation photonic energy matches the transition energy of low-lying excited states in single-end and double-end adsorption configuration. Particularly for the case of the double-end adsorption configuration, the charge transfer states from the excitation from the silver cluster binding to the pyridine ring not only enhance the Raman signals of v(12), v(1), and v(8a) modes, but also selectively enhance the Raman signal of the v(9a) mode associated with the symmetric C-H in-plane bending vibration.国家自然科学基金（21273182,21533006,21373172）资助项

東澳嶺崩塌地之地形演育分析

梅姬颱風 (2010) 與東北季風之共伴效應於台灣宜蘭縣蘇澳地區帶來了豐沛降雨，高累積雨量造成了台9 線蘇花公路群集性土砂災害，尤其在115.9K 上邊坡更誘發了約210 萬m3 之大規模崩塌土砂災害。本文從現地地質調查、致災機制、水文分析及遙測影像判釋等面向進行討論。由降雨-延時-頻率分析得知近年來誘發重大崩塌事件的雨量皆高於200 年回歸週期，並獲致良好判別致災雨場之I-R 圖降雨臨界線關係(Re+53.5Iave=1,146)。多時期遙測影像判釋指出東澳嶺坡頂之弧型張力裂隙仍有持續溯源發展之趨勢。裸露崩塌地不連續面方位密度分布圖之裂隙位態大致與區域地質構造位態 (N70°W) 相近，顯示本區域崩塌主要仍受地質條件主控。此外，蝕溝溯源侵蝕、剪裂帶分布及凹漥坡型亦為影響研究區崩塌地地貌變遷之重要因子，而前期地震或長延時高強度降雨則為外在促崩因子。Typhoon Megi coupled with the northeastern monsoon induced an extreme rainfall of 939 mm on the Suao area, Yilan County, in eastern Taiwan on October 21st, 2010, causing the Dong-Ao Peak landslide of 2.1 million m3 along the coastal Su-Hua Section of Highway Route 9. This study adopts a geological survey, rainfall data, satellite images, orthophotos, and high-resolution DEM based on airborne laser scanner surveys to quantify the morphological changes before and after landslide events following major rainfall events since 2010. Rainfall frequency analysis indicates the cumulative precipitation triggering landslide events is greater than the 200-year return period. In addition, both the entrainment effect of debris flow and toe erosion on the down-slope is shown to induce regressive sliding failure at the adjacent roadbed. The results suggest that geological factors such as head-cutting erosion and the concave landform shape the landform evolution of the catchment. The occurrence of landslides also depends on antecedent earthquake events and extreme intense rainfalls

金电极上偶氮腺嘌呤的电化学行为研究

本文研究了光滑金电极上偶氮腺嘌呤的电化学特性,并确定了相关动力学参数.在含偶氮腺嘌呤的0.2mol·L-1的磷酸盐缓冲液（PBS,pH=4.0～10.0）中,发现其循环伏安图上出现一对氧化还原峰.基于对扫速和伏安峰值电位的分析,结果表明这是一个由吸附控制的可逆偶氮腺嘌呤氧化还原电化学过程.当pH值从低到高改变时,氧化还原峰值向负电位移动,证实H+参与了该反应.通过进一步实验数据分析和电极表面吸附量计算,发现该反应为分步进行的两电子两质子反应.最后,通过快速循环伏安扫描方法确定了电化学过程的表观传递系数α和表观速率常数ks

Effects of CO2-induced seawater acidification on photosynthesis and calcification in the coralline alga Corallina pilulifera

为了探讨CO2海底封存潜在的渗漏危险对于海洋生物的可能影响,以大型钙化藻类小珊瑚藻(COrAllInA PIlulIfErA)为研究对象,在室内控光控温条件下,通过向培养海水充入CO2气体得到3种不同酸化程度的培养条件(PH 8.1、6.8和5.5),24H后比较藻体光合作用和钙化作用情况。结果显示:相对于自然海水培养条件(PH 8.1),在PH 6.8条件下培养的小珊瑚藻光合固碳速率得到了增强,而在PH 5.5条件下光合固碳速率则降低;随着酸化程度的增强,藻体的钙化固碳速率越来越低,在PH 5.5条件下甚至表现为负值[(-2.53±0.57)Mg C g-1干重H-1];藻体颗粒无机碳(PIC)和颗粒有机碳(POC)含量的比值随着酸化程度的加强而降低,这反映了酸化对光合和钙化作用的综合效应。快速光反应曲线的测定结果显示:随着酸化程度的增强,强光引起的光抑制程度越来越强;在酸化条件下,藻体的光饱和点显著降低,但PH 6.8和5.5之间没有显著差异;低光下的电子传递速率在PH 8.1和6.8之间没有显著差异,PH 5.5培养条件下显著降低;最大电子传递速率在PH 6.8时最大,在PH 5.5时最低。以上结果说明,高浓度CO2引起的海水酸化显著地影响着小珊瑚藻的光合和钙化过程,不同的酸化程度下,藻体的光合、钙化反应不同,在较强的酸化程度下(PH 5.5),藻体的光合和钙化过程都将受到强烈的抑制,这些结果为认识CO2海底封存渗漏危险对海洋钙化藻类的可能影响提供了理论参考。Increasing atmospheric CO2 is causing global public concern and seabed sequestration is one possible method of carbon reduction.However,studies on the potential risk of CO2 leakage and its possible effects on the marine environment are still very limited.To investigate such possible effects on sensitive marine organisms,coralline algae,Corallina pilulifera,were cultured under controlled conditions: 20℃,100μmol photons m-2 s-1 and a light period of 12h.Three treatments were set at acidities of pH 8.1,6.8 and 5.5,by aerating natural seawater with pure gaseous CO2.After 24 hours,photosynthesis and calcification rates of C.pilulifera cultured at different pH levels were determined.The rate of photosynthetic carbon fixation was enhanced at the pH of 6.8 and was inhibited at the pH of 5.5,compared with the algae grown in the seawater control(pH 8.1).The rate of calcified carbon fixation was depressed with decreasing pH,and even exhibited a negative value [(-2.53±0.57) mg C(g DW)-1 h-1] at pH 5.5.Additionally,with the decrease in pH,the ratio of particulate inorganic carbon(PIC) to particulate organic carbon(POC) content in the algae,measured with a vario TOC cube,decreased remarkably,which reflected the comprehensive effects of CO2-induced seawater acidification on photosynthesis and calcification.Rapid light curves of algae cultured at different pH levels,which indicated the responses of electron transport rates(ETR) in photosystem II(PS II) to irradiance,were determined by pulse amplitude modulated chlorophyll fluorescence(PAM).The results showed that the photoinhibition term(a) increased with the decrease in pH,indicating that algae grown at lower pH levels experience greater photoinhibition.The light saturation point(Ik) decreased significantly under the CO2-induced acidification conditions,though a significant difference was not found between pH of 6.8 and 5.5.The initial slope of the rapid light curve(α),reflecting the efficiency of the electron transport rate at low irradiance,was lower at pH 5.5 than at the other two levels,while there was no significant difference between pH 8.1 and 6.8 levels.The maximum relative electron transport rate(rETRmax) exhibited the highest value in algae cultured at pH 6.8 and the lowest at pH 5.5.According to these results,we concluded that CO2-induced seawater acidification noticeably affected the photosynthesis and calcification of C.pilulifera,and different degrees of acidification caused different responses of photosynthesis and calcification.At the lowest pH level(pH 5.5),both the photosynthesis and calcification of C.pilulifera were significantly inhibited.These results provide a reference for studies on the risk of CO2 leakage from seabed sequestration methods on the physiology and ecology of marine coralline algae.海洋行业公益项目(200805029和200905020-2);国家海洋局重点实验室基金(200912);近海海洋环境科学国家重点实验室(厦门大学)青年访问学者基金(MELRS1105);山东省科技发展计划项目(2009GG10005012

武夷山亮叶水青冈林物种多样性研究

本文为武夷山自然保护区生物多样性GEF项目内容之一,调查了保护区内不同海拔高度的代表性森林生态系统的物种多样性。亮叶水青冈林是山地的代表性森林生态系统之一。应用Shannon—Wiener多样性指数、Pielou均匀度、Simpson指数和PIE对武夷山亮叶水青冈群落高等植物进行了物种多样性研究。结果表明该群落的Shannon—Wiener指数值为1.2973,Pielou均匀度为34.71％,Simpson指数为2.4777,PIE为0.5964,群落的乔木层物种多样性较高,各项多样性指数分别为2.5757,89.11％,12.1179和0.9175,灌木层、草本层的多样性指数值极低

In situ Raman spectroscopic evidence for oxygen reduction reaction intermediates at platinum single crystal surfaces

铂基催化剂表面的氧还原反应（ORR）是燃料电池重最重要的阴极反应。虽然经过几十年的研究，ORR的具体反应路径并没有真正解析清楚。在本研究中，李剑锋教授课题组首次利用其发展的电化学壳层隔绝纳米粒子增强拉曼光谱（SHINERS）技术原位研究了Pt(hkl)单晶表面的ORR反应过程，成功捕获到在1150 cm-1、1080 cm-1和732 cm-1区域O2-、OH*和HO2*等重要反应中间物种的直接拉曼光谱证据，并通过相应的同位素取代实验（氘和O-18同位素实验）及DFT理论模拟确认了中间物种的谱峰归属和吸附构型。总的来说，该项研究首次在Pt(hkl)单晶表面原位获得ORR反应重要中间物种的直接拉曼光谱证据，提出合理的ORR反应路径，加深了人们对ORR反应机理的认识，也为其他界面催化反应机理的研究提供了一条可行的研究思路。 该研究工作由校内外多个课题组共同努力完成，化学化工学院李剑锋教授课题组负责相关电化学原位拉曼光谱实验，Alicante大学Juan Feliu教授课题组负责单晶电化学实验，化学化工学院吴德印教授课题组负责DFT理论模拟，物理系杨志林教授课题组负责3D-FDTD的理论模拟。该研究工作的第一作者董金超和第二作者张霞光分别为化学化工学院2014级博士生（已毕业）和2015级博士生。【Abstract】Developing an understanding of structure-activity relationships and reaction mechanisms of catalytic processes is critical to the successful design of highly efficient catalysts. As a fundamental reaction in fuel cells, elucidation of the oxygen reduction reaction (ORR) mechanism at Pt(hkl) surfaces has remained a significant challenge for researchers. Here, we employ in situ electrochemical surface-enhanced Raman spectroscopy (SERS) and density functional theory (DFT) calculation techniques to examine the ORR process at Pt(hkl) surfaces. Direct spectroscopic evidences for ORR intermediates indicates that under acid conditions, the pathway of ORR at Pt(111) occurs through the formation of HO2, while at Pt(110) and Pt(100) it occurs via the generation of OH*. However, we propose that the pathway of ORR under alkaline conditions at Pt(hkl) surfaces mainly occurs through the formation of O2- . Significantly, these results demonstrate that the SERS technique offers an effective and reliable way for real-time investigation of catalytic processes at atomically flat surfaces.This work was supported by the NSFC (21522508, 21427813, 21521004, 21533006, 21621091,and 21775127), "111" Project (B16029 and B17027), Natural Science Foundation of Guangdong Province (2016A030308012), the Fundamental Research Funds for the Central Universities (20720180037), and the Thousand Youth Talents Plan of China. Support from MINECO and Generalitat Valenciana (Spain), through projects CTQ2016-76221-P (AEI/FEDER, UE) and PROMETEOII/2014/013 respectively, is greatly acknowledged. V.B.M thankfully acknowledges to MINECO the award of a pre-doctoral grant (BES-2014-068176, project CTQ2013-44803-P). 该研究工作得到国家自然科学基金委（21522508、21427813、21521004、21533006、21621091和21775127）的大力资助和支持。化学化工学院周志有教授、程俊教授，材料学院张华副教授，英国利物浦大学Gary Attard教授，以及化学化工学院苏敏、王耀辉、卢邦安等博士生和杨晓冬博士对本课题的研究给予了大力的支持和帮助

武夷山自然保护区生物多样性研究 1.小叶黄杨矮曲林物种多样性

本文为武夷山自然保护区生物多样性GEF项目内容之一 ,调查了保护区内不同海拔高度的代表性森林生态系统的物种多样性 .小叶黄杨 (Buxussinicavar .parvifolia)林是中山矮曲林的代表性类型之一 .应用Shannon Wiener多样性指数、Pielou均匀度、Simpson指数和PIE对武夷山小叶黄杨群落高等植物进行了物种多样性研究 .结果表明前两者是较好的多样性指标 ,该群落的Shannon Wiener指数值为 1.80 6 8,Pielou均匀度为 49.6 7% ,Simpson指数值为 2 .9146 ,PIE为 0 .6 5 6 9.群落乔木层与藤本植物的物种多样性较高 ,前者各项指数值分别为 2 .2 312 ,71.16 % ,5 .0 783,0 .80 31;后者各项指数值分别为 1.3371,83.0 8% ,3.5 32 7,0 .716 9

中国竹文化旅游资源的开发路径

中国是世界上竹资源赋存十分丰富、开发利用历史悠久的国家,被英国学者称为“竹子文明的国家”。在“中国10大竹乡”和主要竹产地,竹资源对当地的社会、经济、文化和旅游业具有重大影响。中国竹乡以及主要竹产地凭借得天独厚的竹资源优势,努力挖掘其深厚的文化底蕴,以竹文化为主题开展竹文化旅游,获得了较好的经济效益、社会效益和生态环境效益。竹文化旅游资源同时具有自然、历史人文、现代社会3大旅游资源属性,“复合性”为其主要特征,并以“复合型旅游资源”的形式成为竹文化旅游产品的核心组件。竹文化旅游资源主要包括4大亚类,其中包括有形、无形资源形态及非物质文化遗产。竹文化旅游资源内涵丰富,旅游价值高,具有巨大的旅游开发潜力。竹文化旅游产品可极大地满足现实与潜在客源市场需求

Quality of Life in Caregivers of Patients with Breast Cancer and Analysis of the Related Factors

目的：评估乳腺癌患者照顾者的生活质量（QOL），分析影响QOL的相关因素。方法：采用健康调查简表（SF-36），Jalowiec应对量表和一般情况调查表对蚌埠医学院附属医院肿瘤外科123名乳腺癌患者照顾者及门诊110名健康对照者进行调查。结果：乳腺癌患者照顾者的SF-36评分在躯体疼痛、总体健康、精力、社会功能、情感职能和精神健康6个维度比一般健康成人体检者低（P〈0．05和P〈0.01）；“乐观”应对方式上两组比较有显著差异（P〈0.05）；“逃避”、“姑息”、“听天由命”、“情感宣泄”应对方式得分与SF-36多项得分呈显著负相关（P〈0.05或P〈0.01）；情感宣泄、听天由命、姑息、逃避、面对、寻求支持、依靠自我等多个因素进入回归方程，分别对QOL多个维度的变异有预测作用，以“听天由命”对照顾者的QOL的影响作用最大。结论：乳腺癌患者照顾者的QOL比一般人群差；乳腺癌患者照顾者的生存质量与其应对方式密切相关

Quality of Life in Caregivers of Patients with Breast Cancer and Analysis of the Related Factors

目的:评估乳腺癌患者照顾者的生活质量(QOL),分析影响QOL的相关因素。方法:采用健康调查简表(SF-36)、Jalowiec应对量表和一般情况调查表对蚌埠医学院附属医院肿瘤外科123名乳腺癌患者照顾者及门诊110名健康对照者进行调查。结果:乳腺癌患者照顾者的SF-36评分在躯体疼痛、总体健康、精力、社会功能、情感职能和精神健康6个维度比一般健康成人体检者低(P<0.05和P<0.01); "乐观"应对方式上两组比较有显著差异(P<0.05); "逃避"、"姑息"、"听天由命"、"情感宣泄"应对方式得分与SF-36多项得分呈显著负相关(P<0.05或P<0.01); 情感宣泄、听天由命、姑息、逃避、面对、寻求支持、依靠自我等多个因素进入回归方程,分别对QOL多个维度的变异有预测作用,以"听天由命"对照顾者的QOL的影响作用最大。结论:乳腺癌患者照顾者的QOL比一般人群差; 乳腺癌患者照顾者的生存质量与其应对方式密切相关