Optical properties of MoS2 from first-principles calculations

二硫化钼（MoS2）作为典型的过渡金属层状二元化合物，其热稳定性和化学稳定性良好，被广泛应用于固体润滑剂、电极材料和反应催化剂等领域。同时，作为类石墨烯单层过渡金属化合物，单层MoS2凭借其优秀的光学和电学性质在辅助石墨烯甚至替代石墨烯上有着很好的前景，在晶体管制造和电子探针的应用等方面也为人关注，而多层二硫化钼在光学传感器上的应用也逐渐为人们所探索。本文对于体材料、单层及多层二硫化钼的电子能带结构及光学性质进行了研究。 1、 在能带结构计算的基础上，计算出了单层和体材料MoS2的介电函数虚部及实部，并将计算结果与已有的实验结果进行了比较，符合良好。同时指出了体材料及单层MoS2介电函数图像...Molybdenum disulfide (MoS2) is a typical layered transition metal binary compound, has excellent thermal stability and chemical stability and has been widely used in solid lubricant, electrode materials and reaction catalyst, etc. At the same time, as a graphene-like layered transition metal compound, single-layer MoS2 has a very good prospect in assisting graphene or even take graphene’s place be...学位：工学硕士院系专业：物理与机电工程学院_电子与通信工程学号：1982011115287

Barnacle damage and its control in young mangrove plantations: A research review.

随着近年来红树林恢复性造林面积的扩大,海洋污损生物藤壶对红树林幼林的危害问题日益突出.文中综述了藤壶附着的生物化学、藤壶在红树林附着的生态学、藤壶对人工红树林幼林的危害和国内所采用的化学药物防治措施等方面的研究进展,以及今后的研究方向.藤壶在红树林的附着和分布模式受海水盐度、浸淹深度、林分郁闭度、水文条件等环境因素和生物因素的影响.而藤壶胶粘蛋白的氨基酸组成、一维结构,胶粘蛋白在水下的交联、组装和胶粘的过程与机制,以及藤壶危害红树幼苗的机制和危害权重尚需要深入探讨.研究红树植物对藤壶附着的响应和长期适应机制将为藤壶的防治提供更多的启示. 【英文摘要】 With the increasing area of restored mangrove vegetation, marine-fouling organisms, barnacle in particular, are suggested to be an important factor affecting the survival and growth of mangrove seedlings. This paper reviewed the biochemical and ecological studies on the settlement of barnacle, its damage on mangrove seedlings, and its chemical control. The settlement and distribution model of barnacle on mangroves is significantly affected by the environmental factors such as seawater salinity, tide inundat...国家自然科学基金项目(30270272);; 厦门市海洋与渔业局、翔安农林水利局资助项目(2005-2008)

Biomass and growth analysis of Paspalum wettsteinii community in South Fujian, China

禾本科多年生牧草宽叶雀稗适宜在福建南亚热带丘陵酸性赤红壤上生长,人工种植的宽叶雀稗群落鲜草产量峰值在8月份,为4050g·m-2,生物量峰值(干重)则出现在9月份,其中地上部1398.8 g·m-2、地下部770.8g·m-2。群落全年生长呈周期性变化,生物量波动符合Logistic曲线:y=1634.46/(1+e2.67976-1.3.369×10-2t)。根据9月份最高现存量估计,其年净第一性生产力为2169.6g·m-2·a-1。群落生长分4个阶段:缓慢增长(2～4月)、加速增长(5～6月)、减速增长(7～9月)、生长停滞和下降(10～12月)。降雨量是影响生物量的重要因素,二者呈显著线性正相关,相关系数为0.9783,回归方程为y=-74.3779+0.9480x。Paspalum wettsteinii Hackel, a kind of perennial herbages of Graminaea, was proved to get good adaptation to hilly crimson soil in the southern part of subtropical zone in Fujian Province. Its growth curve fluctuated periodically within a year. The biomass value of above-ground part of the community reached to its highest point, 1398. 8 g m-2 in August, 1994; the under-ground part 770. 8 g m-2 in September. Biomass of the community fluctuated in accordance with the logistic curve: y=1634. 46/ (1+e2.67976-1.30369x10-2t) . The highest value of the community's fresh weights measured monthly was 4050 g m-2 (Aug. 1994) . Estimated by Peak Standing Crop in Sept. 1994, the annual NPP of the community was 2169. 6 g m-2 a-1. Through a growth analysis, the above ground part biomass of the community changes with four stages: slow increasing (Feb. -Apr. ); acceleration increasing (May-June); deceleration increasing (July-Sept. ); stagnation and descent (Oct. - Dec. ). Of all the factors that affect the biomass value, the rainfall was an important one. Their regression equation was y= - 74. 3779+0. 9480x, and the relation coefficient (r) was 0. 9783

Design of Communication Interface between MCUs Based on CPLD

介绍了AlTErA公司CPld器件EP1k30芯片的特点,利用MAX+PluS开发软件在EP1k30芯片上设计了一个三通道双向fIfO存储器阵列,实现了一个C8051f020单片机通过总线与其他3个C8051f020单片机的双向数据通信,用于一款嵌入式多路数据通信控制器的实时传输控制。The feature of the EP1K30 of ALTERA's CPLD is introduced.With the development software of MAX+plusⅡ,a three-way dual-direction FIFO memory array is designed on a EP1K30,one C8051F020 MCU can communicates with three other C8051F020 MCUs by BUS,it can be used for real-time transmission control of a built-in multi-way data communication controller

跨海集群工程节能减排关键技术研究

港珠澳大桥跨海集群工程囊括跨海桥梁、沉管隧道、离岸人工岛等多个领域。跨海集群工程由于建设期及运营期能耗巨大,国内外尚无节能减排的成套技术指导工程建设,成为制约跨海集群工程持续发展的瓶颈之一。本文依托港珠澳大桥跨海集群工程建设和运营过程,采用理论研究、数值分析及模拟测试等多种方法,开展了集群工程节能减排指标体系和长大沉管隧道通风、照明、人工岛运营节能减排关键技术研究,成果支撑了工程项目节能减排目标的实现

Ethical Reflection on Standardized Management of Intestinal Microbiota Transplantation

肠道微生态系统是人体健康所必需的重要且复杂的生物系统。肠道微生态系统的紊乱参与人体多种疾病的发生发展过程。而肠菌移植技术可有效调节肠道菌群，修复失衡的肠道微生态，为当今多种胃肠道及胃肠以外疾病的治疗带来新的突破。然而，目前尚缺乏完整的、系统性的肠菌移植技术管理规范。就肠菌移植技术规范化管理所涉及的内容进行探讨，并从医学伦理学角度思考规范化管理中所涉及的伦理问题，以期推动肠菌移植技术的临床应用。Intestinal microecology is an important and complex biological system necessary for human health. Its disorder is involved in the development of various diseases of human body. The technology of intestinal microbio- ta transplantation can effectively regulate the intestinal flora, repair the imbalance of the intestinal microecology, and bring a new breakthrough for the treatment of many diseases of gastrointestinal tract and outside gastrointestinal tract. However, there is still no systematic and complete management standard for intestinal microbiota transplanta- tion technology. This paper discussed related content involved in standardized management of intestinal microbiota transplantation technology and reflected the ethical problems involved in standardized management from the perspec- tive of medical ethics, in order to promote the clinical application of intestinal microbiota transplantation technology

Study on the characteristics of Syzygium cumini L. pigment

以海南蒲桃成熟果实为原料提取天然色素,并对其理化性质进行了分析研究。同时比较了D-072、D-401、D-301-G、D-101、D-110、DF01六种树脂对该色素的静态吸附情况及不同极性解吸剂对吸附色素的树脂洗脱的效果,从中选择吸附和解吸附效果最好的树脂以及适合的解吸剂。研究表明:该色素在酸性条件下对热、金属离子和常用食品添加剂均具有较好的稳定性,对光稳定性稍差;D-072大孔吸附树脂对海南蒲桃色素吸附效果最好,色素吸附率达90.7%;解吸剂用含0.2%三氟乙酸的50%酸化乙醇,色素可被充分洗脱下来。此研究结果为以海南蒲桃成熟果实为原料来生产食用色素提供了理论依据。The stability of pigment which was extracted from the fruit of Syzygium cumini was studied. In addition, absorbing and separating Syzygium cumini pingment with macroreticular resin was also studied. Static absorption capacity of six resins(D-072, D-401, D-301-G, D-101, D-110, DF01) for the pigment was compared. From these resins, the one with the best absorpting and desorpting effect was elected. The results showed that this kind of pigment has a better stability toward heat, metal ion and common food additives under acidic condition, and it is more tolerable of heat than light. The adsorption ability of D-072 resin was the best and the adsorptive rate of pigment reached 90.7%. When 50% ethanol contained 0.2% TFA was used as desorptive solvent, the pigment could be sufficiently desorpted and the effect of desorption would be better. It has a great prospect in the exploration and application in food industry to produce the food pigment from the fruit of Syzygium cumini.国家自然科学基金项目(30671646

Preliminary studies on the scale insect pest of Pseudaulacaspis cockerelli in mangrove

首次发现陆生考氏白盾蚧严重为害潮间带红树植物秋茄。通过野外定位调查和室内饲养观察,研究其危害特征、种群分布、生殖力和自然死亡率。结果表明,考氏白盾蚧主要分布在秋茄叶片主脉两侧,叶背虫口数显著多于叶面(P<0.01),单叶虫口数多为1-50头,平均25.65头,最高418头;秋茄植株不同垂直空间层次的虫口密度无显著差异,但聚集度随垂直空间下降而增大;种群平均产卵量每雌52.22粒,自然死亡率69.35%,寄生蜂寄生是最主要的死亡因子,寄生率达34.23%;与几种陆生寄主植物相比,红树林考氏白盾蚧的种群密度、生殖力、叶最高虫口数均较高,该虫对潮间带生境及寄主秋茄具有适应性。The scale insect,Pseudaulacaspis cockerelli is an important pest for many kinds of plants for a long time in the land.In 2006,it was found firstly attacking the mangrove plant of Kandelia obovata in the tideland in Xiamen City,and had led to badly damages.Based on the field surveys and lab feeding,this paper dealed with its damage characteristic,population distribution,fecundity and natural mortality etc.The results showed that the scale insect mainly distributed on both sides of the midvien of K.obovata leaves,but the individual on the abaxial surface was significantly more than those on the adaxial surface(P<0.01).The individual number of one leaf mostly fluctuated from 1 to 50,and the average and tiptop numbers were 25.65 and 418,respectively.The pest population density had no remarkable discrepancies among different vertical spatial layer of K.obovata,however,its aggregating degree increased with falling of the layer.The population had an avarage fecundity of 52.22 each female and a high natural mortality of 69.53%.The main natural death factor were two species of parasites(Hymenoptera: Chalcididae),and their total parasitical ratio reached 34.23%.In the mass,the pest population density,fecundity and tiptop individual number of a leaf in the mongrove were all more than those in serval other host plants on land,which implied that this scale insect had a high adaptability to the habitat of tideland and the plant of K.obovata

Microbial Study of Mangrove Soil at Dongzhai Harbor in Hainan.

Three groups of microbial amount of mangrove soil at Dongzhai harbor in Hainan were studied.The results show as follows:①Mean amount of soil bacteria in Kandelia candel forest and Bruguiera sexangula forest is 4 87×10 7 and 7 55×10 7〔ind·(g.dry soil) -1 〕 respectively,which is higher than that of controlled mudflat without mangrove forest〔1 22×10 7ind·(g.dry soil) -1 〕;②The amount of bacteria at layer of 10-20cm is the most in three layers of 0-10、10-20 and 20-30cm;③Mean amount of soil bacteria in Bruguiera sexangula forest is higher than that in Kandelia candel forest;④The amount of bacteria is related to the amount and distribution of plant residue and litter;⑤Filamentous fungi and actinomyces are not found out by normal isolation methods,which is perhaps related to least amount and special habitat of local mangrove soil.国家教委高校湿地研究中心专项经费资助项

Critical tidal level for planting Kandelia candel seedlings in Xiamen.

2003年5月在厦门大屿岛白鹭自然保护区西面滩涂上试种秋茄幼苗,研究秋茄的宜林临界线.结果表明,滩涂高程为黄零0.99m处,每个潮水周期的平均淹水时间高达8h,幼苗成活率低于50%,生长缓慢,不适合用秋茄造林;在滩涂高程为黄零1.62m处,秋茄幼苗成活率达90%,生物量积累最大,光合同化作用较高,生长良好,为厦门沿海秋茄的最适生长区;而在高程为黄零1.31m处,秋茄幼苗仍能正常生长.故厦门地区秋茄造林的宜林临界线应不低于黄零1.31m(即厦零4.55m),平均每个潮水周期淹水不高于5.6h.Plantable tidal flat is one of the most important factors affecting the survival rate of mangroves seedlings in forestation.In this paper,an experiment was conducted in the tidal zones of Umbrette Natural Reserve in the Dayu Island of Xiamen in May 2003 to investigate the critical tidal level for Kandelia candel forestation.The results showed that the tidal level of 0.99 m above the zero tidal level of the Huang Ocean was not suitable for planting K.candel seedlings,because the waterlogging time at this tidal level was longer than 8 h per-tide-cycle,and the survival rate was lower than 50%.At 1.62 m above the zero tidal level of Huang Ocean,K.candel seedlings had the best growth and the highest photosynthetic assimilation,with a survival rate of 90%.At 1.31 m above the zero tidal level of Huang Ocean,K.candel seedlings could still grow well.It could be concluded that the tidal level of 1.62 m was optimal for planting K.candel seedlings,and the critical tidal level of K.candel seedlings in the coastal areas of Xiamen was not lower than 1.31 m above the zero tidal level of Huang Ocean,where the waterlogging time was not longer than 5.6 h per-tide-cycle.国家自然科学基金项目(30200031);; 教育部博士点基金项目(20030384007);; 厦门市科技基金资助项目(3502Z20021046)