查询词典 phase transition

Chapter 1 reviews recent investigation in Bose-Einstein condensation, and analyzes critical point and condition of phase transition. Chapter 2 introduces the experiment of Mott insulator and superfluid phase transition in dilute atomic gases, theoretic mode and some studying. In chapter 3, we study the influence of dipole-dipole interaction of two component BEC in optical lattice, by Green function technique and mean-field approach. The results show that long range interaction and dipole-dipole interaction can be strongly influence the phase transition of two component.

本文内容分为四章，第一章对BEC近几年的研究回顾，分析了理想情况下凝聚的临界行为和凝聚条件；第二章我们介绍了光格子中绝缘-超流相变和理论模型及其描述；第三章我们利用格林函数和平均场近似的方法，对偶极-偶极相互作用在光格子中两分量BEC原子的超流-绝缘相变的作用进行了分析，结果表明偶极-偶极相互作用和长程相互作用对绝缘-超流相变有很大的影响。

With the J/y anomalous suppression as a signal of QGP phase transition, on the basis of absorption of nucleons and comovers, the differential cross section of J/y production in high energy heavy ion collisions under the condition of the occurrence of phase transition is derived out, and the experimental data of NA50 collaboration in Pb-Pb collisions at 158A GeV/c is analysed.

以J/y反常抑制现象为夸克-胶子等离子体相变信号，在核与随动者吸收理论的基础上，导出了有相变产生时高能重离子碰撞中的J/y微分产生截面，并对NA50合作组给出的入射动量为158A GeV/c的Pb-Pb碰撞中的实验数据进行了分析，较好地解释了实验结果。

As the supplement of the solidification theory, the melting tamperatures of nanocrystals, the glass transition temperatures of nanosized glasses, the ferromagnetic and ferroelectric transsition temperatures and the solid phase transition temperatures as well as the corresponding hysteresis of different materials are calculated and determined. The effect of the pressure on phase transition temperatures and the binary solution nanophase equilibrium diagram is constructed.

作为凝固理论的补充，计算和测定了纳米晶体的熔化温度，纳米玻璃的玻璃转变温度以及铁磁与铁电居里转变温度，纳米晶体的固态相变温度以及相关的动力学滞后，压力对相变温度的影响，二元无限互溶固溶体的纳米相图。

The conclusions can be drawn through numerical simulation: The hydrate-forming region becomes small with increasing circulation rate and inhibiter concentration, and it is possible to make the hydrate-forming region away from sea floor by increasing circulation rate and inhibiter concentration, thus preventing blowout preventer lines from hydrate plugging; the decrease in gas volume fraction in the annulus due to hydrate formation reduces pit gain, which can delay the detection of well kick; the possibility of hydrate presence at a relatively low gas production rate is much greater than that at a relatively higher production rate; the bottom hole pressure is affected little by hydrate phase transition, and it is allowable not to consider hydrate phase transition when the bottom hole pressure is calculated; shut-in casing pressure cann't truly reflect gas kick due to hydrate formation and the situation is getting worse with time

模拟计算结果表明：溢流期间，天然气水合物的生成区域会随着循环流量的增大或抑制剂浓度的提高而减小，可通过增大流量和抑制剂浓度使水合物的生成区域脱离海底，减小防喷器管线被堵塞的危险；水合物的生成使环空中气体体积分数降低，泥浆池增量减小，给溢流检测带来延迟；当检测到有气侵发生时，水合物藏分解速率比较小时，井筒中生成水合物的可能性要比分解速率大的情况下更为严重；水合物相变对井底压力的影响较小，在工程中计算井底压力时可以忽略；由于天然气水合物的生成使得关井套压值不能真实反应气侵情况，而且随着时间的增加情况会更加严重。

When surface pressures are lower than the turnover(5～30mN/m),intermolecularhydrogen bonds were formed with keto form and phase transition was higher ca.60℃;most of SBC18 formed intramolecular hydrogen bonds companied withzwitterion form and phase transition was lower ca.48℃ while at surface pressurehigher than the turnover(≥45mN/m),which is caused by the different interchaininteraction arising from various hydrogen bonds for SBC18 LB film deposited atdifferent surface pressures.

低于相应π-A等温线转折(5～30mN/m)时，以分子间氢键为主，头基主要以醌式构型存在，相变温度较高(≈60℃)；高于转折(≥40mN/m)时，以分子内氢键为主，头基主要以双性离子构型存在，相变温度较低(≈48℃)。

The phase transition temperature increases and the transition ranges tends to be broad when PNIPA brushes were substituted with P or P(NIPA-co-NVP) brushes obtained by the copolymerization of NIPA with AA and NVP, respectively. However, the phase transition is not obvious if adding excessive hydrophilic comonomer.

结果表明，纯PNIPA刷的相变温度在29℃~33℃之间，通过共聚所得的单一P或P(NIPA-co-NVP)刷均使相转变温度提高，转变区域拓宽，当亲水性共单体的量过多时会导致相变过程不明显。

In this thesis, the crystal structure and phase transition behaviors of a andβforsterite (Mg2SiO4) at high temperature and high pressure were investigated by the first principle calculations and the quasi-harmonic Debye model. Variations of elastic properties, band structure, density of state, band gap ofαandβforsterite with pressure were calculated, and the effect ofα/βphase transition on these characters was analyzed. The effects of water on elastic modulus, sound velocity and band gap of forsterite were also simulated. Finally, the effect ofα/βphase transition and water on seismic discontinuity in earth was discussed.

通过第一性原理结合准简谐德拜模型研究了α和β镁橄榄石的高温高压结构及相变特征；计算了α和β镁橄榄石的弹性模量、波速、电子带结构、带隙等随压力的变化规律，并探讨了相变对这些性质的影响；研究了水对α镁橄榄石弹性模量、波速和带隙的影响；探讨了水对地幔中不连续层的作用以及矿物相变对过渡带波速不连续的作用。

One is low valence vanadium oxide thin films were deposited by direct current facing target magnetron sputtering firstly, and then thermal oxidated; the other is high valence vanadium oxide thin films were deposited by ion beam sputtering, then thermal deoxidated. Vanadium oxide thin films with phase transition were obtained at the lower thermal process temperature 300℃, which is compatible with MEMS technologys. The composition of VO_x thin film fabricated by first method includes mainly VO_2, V2O3 and VO_, the TCR is -2.25%/K, the TCR gradually increases with phase transition temperature decreases. The composition of VO_x thin film fabricated by the second method includes mainly VO_2, V2O5 and V2O3 , and the resulting VO_x thin filmTCR is -3.0%/K. The TCR of phase transition vanadium oxide thin films made by second method is higher than that made by first method for the existance of V2O5 in thin films.

分别采用直流对靶磁控溅射制备低价态氧化钒薄膜再附加热氧化处理的方式，和射频离子束溅射制备高价氧化钒薄膜附加热还原处理的方式获得了具有相变特性的氧化钒薄膜，第一种方式获得相变特性氧化钒薄膜的热处理温度最低为300℃，克服了以往高温条件下热处理不能与MEMS工艺兼容的缺点；相变特性氧化钒薄膜的组分以VO_2为主，含有V2O3和VO_，室温TCR为-2.25%/K；室温电阻温度系数随相变温度的降低逐渐升高；采用第二种方式获得的相变氧化钒薄膜的组分以VO_2为主，含有V2O5和V2O3，室温TCR可达-3.0%/K；分析发现，具有相变特性的氧化钒薄膜中含有V2O5时，室温电阻温度系数明显增大。

This article analyzes the phase diagram of 4 He and λ phase transition of liquid 4 He. Discusses the sorts of the phase transition with vavious temperature and pressure. Indicates the fundamental cause about liquid 4 He named after quantum liquid.

分析了4He的相图和液体4He的λ相变，讨论了在不同的温度和压强下相变的类型，指出了液体4He被称为量子液体的基本原因，介绍了HeⅠ的基本特性，如粘滞系数、热导率，对声波的吸收系数，以及凝聚气体模型。

Combining the mechanism of oxygen diffusion with the block model in YBCO, the mechanism of the phase transitions can he explained as follows: the phase transition at 400℃ comes directly from O(1) in the rock salt block, and corresponds to the beginning of O-T; the phase transition at 850℃ corresponds to the end of O-T, when O(2) and O(3) of Cu(2)-O plain are rearranged and a few oxygen enter O(1) site of Cu(1)-O plain through O(4) bridge atom, and at last escape from the crystal cell. Thus the phase transition at 850℃ is related with the pervoskite block.

结合YBCO中氧扩散机制和块模型，相变机理解释如下：400℃的相变直接来自于岩盐块，对应于正交－四方转变的起点；850℃相变对应于正交－四方转变的终点，此时Cu(2)-O面中的O(2)和O(3)重排，一些O通过O(4)桥原子进入O(1)位，最后逸出晶胞，因而850℃相变与钙钛矿关系密切。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐