温度不均匀分布

The effect of switching modes on the entrancement,combustion and billet heating process in furnace were analyzed numerically,and the computational results were compared with production records and onsite measurement,which verified the practicability of this CFD system.

结果表明：采用分段同侧换向控制的HTAC加热炉能获得很好的流场和温度场分布，基本满足高质量的钢坯加热需要，但该炉在生产条件下的温度制度存在不合理之处，在今后设计和操作中应进一步优化和改进；全同侧换向控制的火焰布置方式不利于钢坯的均匀、快速加热；而采用交叉换向控制的火焰布置方式可以改善加热炉内的流场和温度分布，更有利于满足钢坯的加热工艺要求。

Barrel is the key part of artillery. In shot process, propellent gas of high pressure and high temperature flows in the tube at a high rate of speed, which brings an upheaval to the temperature field of the composite barrel. As to the composite barrel with metal inner, its poor thermal conductivity is more likely to cause uneven temperature distribution and bigger temperature gradient, to produce improper deformation and to make the work temperature of metal inner rise, all of which will affect the life span of barrel.

身管是火炮的关键部件，在火炮发射过程中，高温、高压的火药燃气在身管内成脉冲式高速流动，使身管受到急剧的加热，引起身管壁内的温度急剧变化，而对于带金属内衬复合材料身管，由于复合材料导热性能较差，更容易引起非均匀温度分布以及较大的温度梯度，产生不合适的变形，也会使身管的金属内衬的工作温度升高，从而使得身管的寿命降低，同时身管的发热会引起其刚度的变化，增大射弹散布。

Simulation results also show that saddle-shaped distributed AMF can more effectively inhibit constriction of vacuum arc.

对于小电流扩散态真空电弧，重点仿真分析不同电弧电流与不同纵向磁场对其关键特性的影响，部分仿真结果进行了实验验证；对离子处于超音速流动的收缩态真空电弧的仿真表明，真空电弧的磁收缩主要是由于霍尔效应引起的，离子温度和电子温度沿轴向先增大后减小，马鞍形分布的纵向磁场能够更有效地抑制真空电弧的收缩，而且阴极斑点分布对真空电弧特性也有着显著的影响；对离子处于亚音速流动状态的大电流真空电弧的仿真表明，部分等离子体不能到达阳极而损失，马鞍形分布的纵向磁场能够更有效地抑制电弧等离子体的损失，同时能使阳极电流密度和能流密度的分布更加均匀。

This method makes the best of the advantage of binary optics and liquid crystal-spatial light modulator. It can avoid the unhandy of binary optics and the low efficiency of liquid crystal-spatial light modulator according to the demand. It optimizes temperature uniformity system.

该方法主要是充分利用二元光学法和液晶空间光调制的各自优点，并按照设计系统的要求，最大程度避免二元光学法使用不灵活而液晶空间光调制激光能量利用率不高的缺点，实现温度分布均匀化系统优化。

The results indicate that the different thermal expansions and elastoplastic properties and distributed randomness of various mineral particles composed of oil shale will lead to the nonuniformity of thermal field , deformation field and stress field in heating process , which makes the particles of oil shale deform incompatibly : and the release of product pyrolysis results in irreversible damages of oil shale material and structure . These are the main reasons for the thermal fracture of oil shale .

研究结果表明：组成油页岩各种矿物颗粒热膨胀和弹塑性性质的不同及其分布的随机性，导致油页岩加热过程中温度场，变形场和应力场的非均匀性，使得油页岩颗粒间变形不协调和油页岩热解产物释放引起油页岩材料与结构性能发生不可逆的劣化损伤，这是油页岩发生热破裂的主要原因；热传导方式加热油页岩，温度的传递比较缓慢，加热井和生产井的间距不宜过大，对油页岩储层性质存在差异时，注热井应选择较高热导率的区段；油页岩的层理对油页岩地下原位开发形成渗透带至关重要，油页岩达到热解温度会产生附加的膨胀力，首先在层理处开裂，应充分利用油页岩层理赋存条件改造其渗透性。

The results indicate that the different thermal expansions and elastoplastic properties and distributed randomness of various mineral particles composed of oil shale will lead to the nonuniformity of thermal field, deformation field and stress field in heating process, which makes the particles of oil shale deform incompatibly: and the release of product pyrolysis results in irreversible damages of oil shale material and structure. These are the main reasons for the thermal fracture of oil shale. When oil shale is heated through thermal conduction, temperature transfers slowly, so the spacing between heating well and production well should not be kept too long. When difference exists in oil shale reservoir's properties, heating well should be chosen in the high conductivity region. Oil shale's stratification is vital for developing permeation zone in in-situ retorting. Oil shale will generate additional expansion force as it reaches its pyrolysis temperature, and stratification will be cracked first, so the oil shale stratification should be utilized to enhance its permeability.

研究结果表明：组成油页岩各种矿物颗粒热膨胀和弹塑性性质的不同及其分布的随机性，导致油页岩加热过程中温度场、变形场和应力场的非均匀性，使得油页岩颗粒间变形不协调和油页岩热解产物释放引起油页岩材料与结构性能发生不可逆的劣化损伤，这是油页岩发生热破裂的主要原因；热传导方式加热油页岩，温度的传递比较缓慢，加热井和生产井的间距不宜过大，对油页岩储层性质存在差异时，注热井应选择较高热导率的区段；油页岩的层理对油页岩地下原位开发形成渗透带至关重要，油页岩达到热解温度会产生附加的膨胀力，首先在层理处开裂，应充分利用油页岩层理赋存条件改造其渗透性。

The effects of the spray-drying process of the ammonium paratungstate and the carburization temperature on the formation of the precusor and WC powder were investigated.

采用喷雾干燥-固定床法制备碳化钨粉末，研究了喷雾干燥和碳化反应温度对制备偏钨酸铵前驱体以及碳化钨的影响，前驱体粉末呈现均匀的球状形态，平均粒径为10~20μm，喷雾温度对影响粒径大小和分布影响小；400℃的进口温度下进行喷雾干燥，喷雾粉末仍然保持偏钨酸铵原来的基本组成不发生分解。

When the solid state laser is operating, the waste heat stored in the laser medium cause ununiformity of the temperature distribution in the medium, which will result in the wavefront distortion and the beam quality degradation.

固体激光器工作时，由于激光介质中沉积的废热，引起激光介质温度分布不均匀，导致激光波前热畸变，光束质量下降。

Furthermore,the influences of hot working parameters,such as friction factor,the top die speed and initial die temperature,on the temperature distribution had been investigated,and the temperature distribution in different deformation zones was analyzed.

同时由于坯料与模具和环境之间存在着温度差，以及坯料和模具接触面上的摩擦功不断转化为热量，使得坯料在变形的同时，将以各种形式和模具及周围环境进行热交换，增加了坯料内部温度场分布的不均匀性。

In the thermophilic stage, both the duration of high temperature and the distribution of pile temperature in Pile Ⅱ with time control aeration mode were better than those in Pile I with time-temperature control aeration mode.

在高温持续时间和温度分布均匀性方面，采用时间控制通风的堆肥方式优于采用时间-温度联合控制通风的堆肥方式，但过高的温度(60～70℃)不利于堆体中水分的去除和有机质的生物降解在高温堆肥阶段，通过改变通风时间，2种控制方式的堆肥过程均出现了2次高温期，这更利于堆肥的无害化。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。