Influences of marine floor hydrothermal activity on organic matter abundance in marine carbonate rocks——A case study of middle-upper Proterozoic in the northern part of North China

FOR A LONG TIME, RESEARCHERS HAVE BEEN REGARDING THE BIOLOGICAL PRODUCTIVITY, THE SEDIMENTATION RATE, THE DEPOSITION ENVIRONMENT, AND THE PRESERVATION CONDITION OF THE DEPOSITIONAL ORGANIC MATTER AS THE CONTROLLING FACTORS OF ORGANIC MATTER ABUNDANCE IN T…     

Synthesis of nanoporous silica with interior composite cells with synthetic block copolypeptide as template

IN NATURE,PROTEIN AND POLYSACCHARIDE ARE INVOLVED IN THE FORMATION OF A REMARKABLE DIVERSITY OF EXQUISITE NANOSTRUCTURED SILICATES IN BIOLOGICAL SYSTEMS SUCH AS DIATOMS AND SPONGES.THE SILAFFIN[1]AND SILICATEIN[2]ISOLATED FROM MARINE DIATOMS AND SPONGES C…     

A multiscale soil loss evaluation index

IMPROPER LAND USE BY MANKIND IS ONE OF THE MAIN CAUSES OF SOIL EROSION[1].THROUGH CHANGING VEGETATIVE COVER,SOIL PROPERTY AND RUNOFF VELOCITY,LAND USE AFFECTS THE OCCURRENCE AND DEVELOPMENT OF SOIL EROSION[2―5].AS SCALE CHANGES,NOTABLE CHANGES WILL OCCUR IN THE INTER-ACTIVE MECHANISMS BETWEEN LAND USE AND SOIL EROSION.CURRENTLY,RESEARCH ON LAND USE AND SOIL EROSION IS CHAN…     

Evaluation of the introgressed lines and screening for elite germplasm in Gossypium

THERE ARE 51 SPECIES IN THE GENUS OF GOSSYPIUM[1]. EXCEPT UPLAND COTTON CULTIVARS, WILD CULTIVARS, SPECIES AND RACE HAVE ABUNDANT GENETIC POLYMORPHISMS DUE TO THEIR VARIOUS ENVIRONMENTAL DISTRIBUTION AND LONG-TERM NATURAL SELECTION. THEREFORE, THEY POSSESS LOTS OF EXCEL- LENT GENES THAT CAN BE USED TO EXPLOIT POTENTIAL TRAITS, SUCH AS DROUGHT RESISTANCE, DISEASE AND INSECT …     

A NEW DESCRIPA NEW DESCRIPTOR OF AMINO ACIDS BASED ON THE THREEDIMENSIONAL VECTOR OF ATOMIC INTERACTION FIELD

QUANTITATIVE STRUCTURE ACTIVITY RELATIONSHIP (QSAR) IS A VERY IMPORTANT TOPIC FOR MANY SCIENTIFIC FIELDS AND CAN BE TERMED AS QUANTITATIVE SEQUENCE ACTIVITY MODELS(QSAM)[1] WHEN REFERRED TO THE RESEARCH ON RELATION- SHIPS BETWEEN STRUCTURES AND ACTIVITIES OF BIOLOGICAL MOLECULES, SUCH AS PROTEINS, AND NUCLEIC ACIDS. HOW- EVER, IT IS VERY DIFFICULT TO ESTABLISH A QSAM MODEL,…     

Quantitative structure-activity relationship of estrogen activities of bisphenol A analogs

BISPHENOL A (4,4-ISOPROPYLIDENEDIPHENOL, BPA) IS MANUFACTURED IN HIGH QUANTITIES, WITH 90% OR MORE BEING USED AS A MONOMER FOR THE PRODUCTION OF POLYCARBONATE AND EPOXY RESINS, UNSATURATED POLYESTER-STYRENE RESINS AND FLAME RETARDANTS. THE FINAL PRODUCTS …     

Materials informatics and study on its further development

NOWADAYS,WITH THE DEVELOPMENT OF MATERIALS SCI-ENCE AND TECHNOLOGY AND WITH THE CONTINUOUS EMER-GENCE OF NEW MATERIALS,TECHNOLOGIES,PROCESSES AND METHODS,PROLIFERATION AND COMPLEXITY OF MATERIAL SCI-ENCE DATA HAVE INCREASED ENORMOUSLY.THEREFORE,DIFFI-CULT…     

A new improved structure of dye-sensitized solar cells with reflection film

DYE-SENSITIZED NANOCRYSTALLINE SOLAR CELLS (DSSC), RECENTLY DEVELOPED BY MICHAEL GR?TZEL[1], HAVE BEEN ATTRACTING CONSIDERABLE ATTENTIONS BECAUSE OF ITS HIGH EFFICIENCY, SIMPLE FABRICATION PROCESS AND LOW FABRICA- TION COST[2]. TYPICAL DSSC[3] IS BASED ON A SANDWICH STRUCTURE, WHICH CONSISTS OF TWO GLASS PLATES WITH A TRANSPARENT CONDUCTING OXIDE (TCO) COATING AS SUBSTRATE. O…     

Barrier layer in the northeastern South China Sea and its formation mechanism

A VERTICALLY UNIFORM LAYER OF TEMPERATURE(ISOTHERMAL LAYER),SALINITY(ISOHALINE LAYER)AND DENSITY(MIXED LAYER)IS USUALLY FORMED IN THE UPPER OCEAN DUE TO THE WIND STIRRING.UNDERNEATH IS THE LAYER WITH RELATIVELY STRONG VERTICAL GRADIENT AS THE THERMOCLINE,…     

Asymmetry between the upper and lower visual fields： An event-related potential study

ASYMMETRIES OF HUMAN VISUAL INFORMATION PROCESS- ING ACROSS VISUAL FIELDS HAVE BEEN AN INTERESTING ISSUE IN COGNITIVE PSYCHOLOGY AND NEUROSCIENCE. IN ADDITION TO INVESTIGATIONS OF THE ASYMMETRIES BETWEEN THE LEFT AND RIGHT VISUAL FIELDS THAT ARE BELIEVED …     

射频电感耦合闭式等离子体产生与光谱诊断的实验

设计了一种闭式等离子体发生装置,采用射频电感耦合方式,以氩气为工作气体,在封闭式腔体低气压环境下进行放电实验。利用发射光谱法,测量了密闭腔体侧面方向的Ar谱线数据,研究了等离子体电子激发温度和电子密度随空间位置的分布规律以及不同射频功率对电子激发温度和电子密度的影响。等离子体中电子激发温度的变化通过玻尔兹曼斜率法进行分析,电子密度的变化则通过分析Ar原子750.4nm谱线强度变化获得。实验结果表明,该发生装置能够产生均匀持续的等离子体层,等离子体中电子激发温度约为9 500K。等离子体电子密度和电子激发温度随着输入射频功率的增加而增大,但变化幅度在减弱;当足够的输入功率时,等离子体层参数随位置的变化幅度较小。     

纳米Zn1-xCuxO薄膜的结构及光学性质

采用射频磁控溅射制备了不同Cu掺杂浓度的ZnO薄膜．以X射线衍射、扫描电镜等对薄膜的结构和形貌进行了表征,XRD和SEM测试结果显示Cu掺杂量为5．0at．％时,Zno9,Cu0.05O薄膜呈纳米柱状结构．同时也对薄膜的光致发光（PL）进行了研究．结果表明,406nm的发光峰源于带边自由激子电子的复合,440nm的发光峰则和薄膜中的锌间隙Zni缺陷有关．     

溅射功率对GeSb2Te4膜形貌及力学性能的影响

利用电子回旋共振CVD设备的射频磁控溅射方法制备了GeSb2Te4膜,采用原子力显微镜、纳米硬度计以及侧向力显微镜考察了不同溅射功率对GeSb2Te4膜表面微观结构以及力学性能的影响．结果表明：在一定的溅射功率范围内,由于薄膜生长方式从三维向二维的转化,薄膜的表面粗糙度随功率的增大而降低,而且薄膜致密度也随之提高,从而使得非晶态GeSb2Te4膜硬度和弹性模量增大．利用能量密度理论对这一现象进行了分析．另外,由于表面能等因素的影响,功率为63W制备的GeSb2Te4膜粘附力较高,摩擦系数却较小．     

Enhancement of the thermo-mechanical properties and efficacy of mixing technique in the preparation of graphene/PVC nanocomposites compared to carbon nanotubes/PVC

Thin films of poly vinyl chloride(PVC)/multiwalled carbon nanotubes(MWCNT) and PVC/graphene(GN) nanocomposites were prepared by mixing in the presence of different quantities of nanoparticles. Film casting was performed using tetrahydrofuran as a solvent. The as-prepared PVC/MWCNT and PVC/GN nanocomposites were characterized by scanning electron microscopy, Raman spectroscopy, X-ray diffraction,thermogravimetric analysis, differential scanning calorimetry, dynamic mechanical analysis, and diffused reflectance spectroscopy. Only the PVC/GN nanocomposite films were evaluated further for detailed mechanical analysis because of the poor dispersion of MWCNTs in PVC. The PVC/GN nanocomposite films were thermo-mechanically more stable than the PVC films. These nanocomposites have potential as a replacement material for PVC and PVC/MWCNT owing to their better dispersion and high stability.     

铜膜制备过程中辉光等离子体的双探针诊断

采用Langmuir双探针技术对氩气环境下射频磁控溅射铜薄膜过程中产生的辉光等离子体进行了实时诊断.结果表明,在一定的射频功率下,电子温度随气压的增大呈指数衰减的趋势变化;在一定的反应气压下,电子温度和电子密度随射频功率的增大均呈线性增加的趋势.电子的运动速度数量级为106 m/s.比离子的运动速度大3个数量级.     

用于FBAR的C轴取向AlN压电薄膜的研制

用射频（RF）反应磁控溅射法,在硅基片上制备出了具有较低表面粗糙度、C轴择优取向的AlN压电薄膜.讨论了溅射功率对AlN压电薄膜结构和形貌的影响、氮气含量对AlN压电薄膜成分的影响以及低温退火对薄膜表面粗糙度的影响.XRD和SEM结果表明：随溅射功率增大,AlN压电薄膜C轴择优取向增强;当功率为350W时,AlN压电薄膜（002）面摇摆曲线半高宽为4.5°,薄膜表现出明显的柱状结构.EDS成分分析表明：随氮气含量的提高,AlN压电薄膜的元素比接近于化学计量比.低温退火工艺的引入将薄膜表面的均方根粗糙度由4.8nm降低到2.26nm.     

远程氧等离子体对大肠杆菌的灭菌效果与机理研究

采用Langmuir双电子探针和电子自旋共振诊断技术分别定量测定了远程氧等离子体场中各活性物种的分布.考察了远程氧等离子体对医用聚四氟乙烯表面大肠杆菌的灭活作用,并通过对灭菌后菌悬液蛋白质泄漏量、脂质过氧化物生成量及细菌DNA电泳图的测定分析了其灭菌机理.结果表明:远程氧等离子体中的电子、离子浓度随远程距离的增大迅速降低,30 cm后接近于0,而自由基浓度则相对降低缓慢,40 cm处仍为初始浓度的70%;远程氧等离子体60 s内的灭菌效果值在放电区可高达3.42,在远程距离40 cm以内也均在3.32以上,符合消毒灭菌的要求;电子、离子对细菌细胞膜的快速刻蚀及自由基对胞膜中多价不饱和脂肪酸的攻击分别是放电区及远程30cm后灭菌的主要原因.氧等离子体中紫外光的灭菌效果微弱.     

金刚石薄膜绝缘电阻的时间效应与表面处理

本文研究了常规热丝ＣＶＤ法生长的金刚石薄膜的绝缘电阻特性，发现薄膜从反应取出后其电阻会随时间降低至某一稳定值（时间效应）。用浓硫酸和双氧水的混合液、或氩等离子体对薄膜进行表面处理，可以提高电阻５￣６个数量级，且不再随时间变化；而氩气气氛下的加热处理效果不大。文中还提出了产生电阻时间效应的原因和提高薄膜绝缘电阻的方法。     

Preparation and performance of novel LLTO thin film electrolytes for thin film lithium batteries

We prepared a series of lithium lanthanum titanate(LLTO) thin film electrolytes by radio frequency(RF) magnetron sputtering using LLTO targets in a N2 atmosphere.We also deposited the LLTO thin films in an Ar atmosphere under a same condition as references for comparison.The microstructure morphology and the composition of the thin films were investigated by X-ray diffraction(XRD),scanning electron microscopy(SEM) and X-ray photoelectron spectroscopy(XPS),respectively.Results show that the thin film has an amorphous structure with a uniform surface and it is free of pinholes and cracks.Impedance measurements reveal that the ionic conductivity of the electrolytes is beneficial for all solid lithium batteries dependent on the lithium content at room temperature.We found that the amorphous LLTO thin film performs well and it has potential application in microbatteries for use in microelectronic devices.     

氩环境气压对激光烧蚀沉积纳米硅薄膜形貌的影响

采用脉冲激光烧蚀技术在氩气环境下制备了纳米硅薄膜,研究了环境气体压强对纳米硅薄膜表面形貌的影响. 结果表明,当环境气压小于50 Pa时,薄膜表现为常规的量子点镶嵌结构;当环境气压大于50 Pa时,薄膜中出现类网状的絮结构,继续增大氩气压,絮结构逐渐增大,且其隙度增大. 指出该现象与在激光烧蚀过程中纳米硅团簇的形成过程有关.