基于FTO的TiO_2纳米管阵列可控制备

采用直流磁控溅射法在透明导电玻璃FTO上制备了表面平整、致密度高的Ti膜,经过在含氟化物电解液中的阳极氧化过程后得到了垂直于FTO的高度有序的Ti O2纳米管阵列.通过调节阳极氧化反应过程中的电压、温度参数,得到了一系列具有不同孔径、壁厚、长径比、管密度的TiO2纳米管阵列,从扫描电镜(SEM)的结果中可以得出,Ti O2纳米管的各项管参数与反应条件电压、温度呈线性关系.其中,氧化电压对纳米管管径起主要影响作用,管内径由49.3 nm至75.3 nm连续可调,而温度对纳米管壁厚起明显作用,管壁厚度从11.6 nm变化到38.1 nm.由此得到的多尺寸TiO2纳米管阵列对前入式光照的光伏器件的应用具有重大意义.     

阳极氧化TiO_2纳米管阵列的制备与表征

采用阳极氧化法,分别选用HF和NH4F两种电解质,对纯钛进行阳极氧化处理制备TiO_2纳米管阵列。选用扫描电子显微镜、透射电子显微镜、能谱及X-射线衍射对纳米管的形貌、化学成分和物相结构进行表征和分析。结果表明:在HF体系中,随着氧化时间的增加,纳米管整齐度增加,同时管径也增大,当氧化时间为20 min时,管内径约60 nm,壁厚约10 nm;而纯钛片厚度的变化对纳米管的形貌没有明显的影响。在NH_4F体系中,加热使纳米管的内径增加,壁厚变薄,内径达到130 nm,壁厚约7 nm,这是由于加热使氧化反应速率增加,加快了纳米管的形成速率。EDS检测的Ti和O的原子数的比例接近1∶2。XRD图谱表明,在450℃热处理后的纳米管的物相结构为锐钛矿,由此可见,阳极氧化制备的纳米管阵列为二氧化钛纳米管。     

CoFe2O4纳米管的合成与表征

利用阳极氧化铝模板,用化学方法合成了CoFe2O4纳米管.X射线衍射结果表明,纳米管由无择优取向的、立方尖晶石结构的多晶CoFe2O4构成.电子显微镜显示,纳米管管径约300 nm,管壁厚度约100 nm,由约30 nm的CoFe2O4颗粒组成.进一步的磁性测量表明,纳米管阵列无明显的各向异性,其矫顽力约1 kOe,磁滞回线的方形度约0.37.     

TiO_2纳米阵列管的制备及其光电转换性能研究

以阳极氧化法制备了高度有序的 TiO_2纳米阵列管.通过XRD、UV-Vis DRS、SEM等对样品结构、组成、形貌和光吸收性能进行了表征,表明制备的样品主要为锐钛矿型 TiO_2纳米管,管长约10mm、管径为90nm.在模拟太阳光下,通过测试样品光电流响应评价光电转换性能.考察阳极氧化电压、氧化时间、焙烧温度和时间等对样品光电流密度的影响.当氧化电压为40V,氧化时间为12 h时获得的前驱体通过焙烧温度为400℃,维持4 h后再升温到600℃并保温1h所得样品的光电流密度最大,为2.09m A/cm~2.     

多孔钛片上二氧化钛纳米管束的制备与表征

在氢氟酸电解液中采用阳极氧化法在多孔钛片上制备了二氧化钛纳米管束.考察了电压对二氧化钛氧化层形貌及温度对二氧化钛晶型的影响.制备的二氧化钛纳米管形貌,晶型及光催化性能分别采用SEM,XRD和光催化还原Pd2+沉积钯膜实验表征.SEM结果表明,最佳阳极氧化电压为30 V.在此电压下制备的二氧化钛纳米管长约为300 nm, 管径约为40 nm, 壁厚约为20 nm.XRD结果显示, 773 K退火后,二氧化钛为锐钛矿型;873 K退火后二氧化钛主要为锐钛矿型,含有2.99% 的金红石相;973 K退火后二氧     

TiO2纳米管薄膜的制备与光学性能研究

用阳极氧化法以NH4F和含水丙三醇作电解液在室温条件下制备TiO2纳米管薄膜。采用扫描电子显微镜（SEM）、X射线衍射分析（XRD）和紫外可见光谱分析（UV-Vis）对纳米管薄膜的结构与性能进行表征,研究阳极氧化电压、退火处理对TiO2纳米管薄膜形貌的影响。研究结果表明：随着阳极氧化电压的增高纳米管直径增大,当阳极氧化电压为70V,80V,90V,100V时制备的纳米管直径为143nm,167nm,191nm,215nm;在阳极氧化电压为100V、退火温度为380℃时制备出的TiO2纳米管薄膜的吸收性能最好,其吸收率在紫外光区达到92%。     

磷酸电解液中TiO2纳米管的形貌及光吸收性能研究

采用阳极氧化法在磷酸电解液中制备TiO2纳米管,通过SEM 和UV-VIS-DRS表征分析,研究阳极氧化电压、氧化时间、煅烧温度、电解液组成等制备条件对 T iO2纳米管形貌和光吸收性能的影响．结果表明,在H3 PO4电解液体系中,阳极氧化法制备 T iO2纳米管的最佳条件为：阳极氧化电压20V ,阳极氧化时间60min ,V（H3 PO4）∶V（NH4 F）＝1∶1,煅烧温度为500℃．此时纳米管管径80～100nm ,在可见区有较强的吸收且吸收边界红移．     

锐钛型TiO_2纳米管阵列的制备及微结构调控

采用阳极氧化法,系统考察了HF体系中氧化电压、氧化时间、质量分数、p H值和退火温度等对钛基表面二氧化钛纳米管阵列形成过程中物相和微观形貌的影响,探讨了制备规整性、均一性及微结构可控的二氧化钛纳米管阵列的主要和次要因素.研究结果表明:氧化电压、p H值是决定TiO_2纳米管阵列是否形成与规整性的决定因素.较小的p H值虽然有利于在较短的时间内制备TiO_2纳米管阵列,但容易导致基体表面TiO_2纳米管脱落,影响纳米管阵列的完整性和均一性.氧化电压在15~25 V,p H值为4~6内可以实现TiO_2纳米管阵列的微结构调控.氧化时间、电解液浓度主要影响TiO_2纳米管的管长、管径、管壁厚度,只要在合适的范围内可以通过微小的改变,实现微结构的调控.退火温度决定了TiO_2的晶相转变,不同的退火温度对TiO_2纳米管的管径、管壁、规整性、均一性影响较小,过快的升温和较高的温度不利于锐钛型TiO_2纳米管的形成,可以实现在较低温度下的晶相转化.     

Ag改性TiO_2纳米管阵列的光电化学性能研究

采用阳极氧化法及光沉积法制备Ag改性Ti O2纳米管阵列,采用XRD、SEM分析样品的晶型和形貌特征,并利用电化学工作站三电极体系通过I-E、光生电位、光电流响应及莫特肖特基曲线考察样品的光电化学性能。结果表明:Ti O2纳米管阵列的内径约为60 nm,管壁厚度约为30 nm,Ag颗粒粒径为15~20 nm;光沉积时间对Ag颗粒尺寸几乎没有影响,仅增加了Ag粒子的沉积量;Ag的改性能够有效地促进电子和空穴的分离,提高了对太阳光的利用率,在氙灯照射下,Ag-Ti O2纳米管阵列具有良好的光电化学性能,光电流达到0.28 m A/cm2,载流子密度ND为2.21×1022cm-3,光转化率可达到4.10%。     

Ag改性TiO_2纳米管阵列的光电化学性能研究

采用阳极氧化法及光沉积法制备Ag改性Ti O2纳米管阵列,采用XRD、SEM分析样品的晶型和形貌特征,并利用电化学工作站三电极体系通过I-E、光生电位、光电流响应及莫特肖特基曲线考察样品的光电化学性能。结果表明:Ti O2纳米管阵列的内径约为60 nm,管壁厚度约为30 nm,Ag颗粒粒径为15~20 nm;光沉积时间对Ag颗粒尺寸几乎没有影响,仅增加了Ag粒子的沉积量;Ag的改性能够有效地促进电子和空穴的分离,提高了对太阳光的利用率,在氙灯照射下,Ag-Ti O2纳米管阵列具有良好的光电化学性能,光电流达到0.28 m A/cm2,载流子密度ND为2.21×1022cm-3,光转化率可达到4.10%。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-