压下的

The investigation shows that plenum chamber total pressure has multifarious effects on arcjet thruster operation, and both specific impulse and thrust efficiency can be improved by increasing it befittingly under steady arc.

研究表明，集气腔总压对推力器工作过程具有多方面的影响，在保证电弧稳定的情况下，适当提高集气腔总压可同时提高比冲和推进效率。

With this method a model of the large offset, highly compact intake is made and tested meticulously at low and high speeds. In the paper the distribution of the total pressure at the exit section and the static pressure along the wall of the intake is given at low speed, and the performance of the intake has measured at different Mach numbers, incidences and yaws.

并借鉴S形进气道的设计方法完成了高偏距、短扩压埋入式进气道的设计，并对该埋入式进气道的高、低速性能做了细致的研究，给出了0.1马赫数下进气道出口截面上的总压分布、总压畸变、壁面静压分布，以及0.5～0.8马赫数范围内，该进气道模型在-7°～10°攻角范围和8°侧滑角范围内的性能。

When the gas flux is constant, the ratio of reduced resistance is improved with the increase of the water stream velocity. However, the relationship between the gas flux and the ratio of reduced resistance is more complex. When the water stream velocity is constant, if the gas flux is small in contrast, the effectiveness of reduced resistance is not obvious. But when the gas flux increased, the jetted gas will form """"archform"""" which will augment the shape resistance. In this condition, resistance could not be reduced and could even be increased, if the gas flux continues to be increased. So that there needs setting a baffle called step, which introduces the jetted gas into the turbulence boundary layer. In this case, the shape resistance may be fairly great. Besides, the waterline of model has also some effect on the ratio of reduced resistance, which acts on the size of wave. If waterline is deep, the wave could not affect the deployment of microbubble layer, so there is almost no effect on ratio of reduced resistance. However, the wave would affect distributing of microbubble layer under the model so that the gas could leak out from the two sides of model and directly affect the ratio of reduce resistance if the waterline is very small. Whether installing the dashplate or not has also the great influence on the effectiveness the ratio of reduced resistance. From the results of experiment, conclusion is that adding dashplate will greatly improve the effectiveness of reduced resistance.

当喷气量一定时，水流速度增大，减阻率提高；喷气量与减阻率之间的关系比较复杂，速度一定时，如果喷气量较小，减阻效果就比较差，但当喷气量增大的话，喷射出的气体就会形成一个&拱度&，增加了船模的形状阻力，在这种情况下最好采取断阶喷气，把气体引入到湍流边界层中，在这种情况下，船模的形状阻力比较大；船模的吃水对减阻率也有一定的影响，主要表现在波浪大小上，如果吃水较深，波浪影响不到微气泡层的分布，对减阻率不会造成太大影响，如果吃水较浅，波浪就会影响到微气泡层在船模底部的覆盖情况，可能会有部分微气泡从船模两侧泄漏，这样就直接影响到了减阻效果；是否安装压浪板，对减阻率也有较大的影响，从试验结果可以看出，在船模尾部加设了压浪板时，减阻效果明显得到改善。

Three types of subgrade filling material are selected to analyze the change rule of subgrade resilience modulus under different compaction. Meanwhile PFWD（portable falling wei-ght deflectometer） is combined to integrate this parameter with compaction of construction control index,which brings about the conversion relation between three subgrade filling material and compaction. It can provide reference for pavement design and construction.

选定三种不同类型的路基填料，分析在不同压实度条件下路基回弹模量的变化规律，并结合PFWD检测方法，将设计参数回弹模量与施工控制指标压实度联系起来，得出三种路基填料的回弹模量与压实度的转换关系，可为路面设计与施工提供合理的依据。

Solubility and stability of calcium arsenates under different CO2 pressures are studied based on the data of precipitation and solution experiments simulated by PHREEQC program. The result shows that calcium arsenates can dissolve incongruently by the effect of CO2 in high pH（pH〉8. 3）and make their solubility higher. The higher the CO2 pressure is, the lower the acidity of the incongruent dissolution is.

文章摘要：通过沉淀和溶解两方面的实验数据，应用PHREEQC程序模拟了砷酸钙在不同CO2分压条件下溶解度的变化情况，发现环境中的CO2可使砷酸钙盐在酸度较高（pH大于8.3）的条件下发生不一致溶解，使其溶解度升高；CO2分压越大，砷酸钙盐发生不一致溶解的酸度越低；CO2主要影响3：2和5：3的砷酸钙盐，而对4：2砷酸钙盐的影响较小。

Is the service of agriculture and animal husbandry scientific research, production and sales of private high-tech enterprises, has experienced professional and technical personnel, and to a number of agricultural colleges and universities, research institutes co-operation long-term commitment to crop stalks, pasture Press Processing Products and processing equipment research and development, in the absorption of advanced technologies at home and abroad on the basis of summing up the company many years of experience in China Nongda Prataculture Center, Chinese Academy of Agricultural Mechanization and other units of projects under the support and cooperation for China's rural market, developed a series of crop stalks briquette briquette processing products and complete sets of equipment, mechanical products have achieved the provincial level to promote a permit under the "2006-2008 National supporting the promotion of the Products directory of agricultural machinery."

河北富润农业科技开发有限公司是服务于农牧业的集科研、生产、销售于一体的民营高新科技企业，拥有经验丰富的专业技术人员，并和多家农业院校、研究院所合作，长期致力于农作物秸秆、牧草压块产品加工工艺和加工成套设备的研究和开发，在吸收国内外先进技术的基础上，总结公司多年经验，在中国农大草业中心、中国农机化院等单位对项目支持与合作下，针对我国农村市场，研发出系列农作物秸秆压块加工工艺和压块产品加工成套设备，取得了省级机械产品推广许可证，被列入《2006-2008年国家支持推广的农业机械产品目录》。

The experimental investigation demonstratesthat (1) the critical perforation energy of pressure pipelines (D/H=15) with pressure OMPa under lateral impact of flat-nose and spherical-nose indenters ranges from 2~3%,the critical perforation energy of empty pipelines is higher 1 ~2% than pipelines filled in water without pressure.

实验研究结果表明：(1)当管梁内注满水，预加工作内压P=0MPa时，对于径厚比D／H=15的厚壁圆管，在平头弹体和球形弹体两种弹体冲击作用下临界穿透破坏能量的降幅在2～3％之间：锥头弹体冲击厚壁空管的临界穿透能量比充水预加内压为P=0MPa的圆管高1～2％：(2)充水管道的预加内压提高，临界穿透能量有一定降低。

Since the turbine-driven feedwater pump failed to regulate directly the drum level of single boiler and problems like pressure overrun of main feedwater pipe existed, DCS was utilized to solve the problems for its features of shared information, powerful configuration functions and easy modification.

在对国电成都热电厂嘉陵2×142MW机组两炉一机单元给水系统控制方式进行分析的基础上，针对运行中出现的汽动给水泵不能直接调节单台锅炉汽包水位及给水母管压力超限等问题，利用分散控制系统信息共享、组态功能强大、修改方便的特点，在不增加硬件设备的情况下，通过软件组态增加了汽动给水泵调节单台锅炉汽包水位调节回路和给水母管超压及欠压保护回路，实现了机组在一炉一机单元运行和两炉一机母管运行2种运行方式下给水自动的合理控制，并解决了给水母管的压力保护问题，提高了机组运行的安全可靠性。

The existence ofpolar nanoregions dramatically influences the extrinsic dielectric nonlinearityof paraelectric phase. 5 Slow relaxations of field induced piezoelectricresonance of paraelectric barium stannate titanate were observed after eitherapplying or removing a DC bias field. This phenomenon is attributed to slowspace charge dipoles formed by injected homocharges and validated by theobservation of a negative piezoelectric constant. Isothermal study ondielectric constant and discharging current after application or removal of astep field were performed. The relaxation laws in ferroelectric andparaelectric phases are different. The transportation of homocharges arebelieved to be responsible for the strong relaxation behavior in paraelectricphase. Domain wall can trap space charges thus the relaxation in ferroelectricphase is relatively weak. Abnormal phenomena, such as slim-waisted hysteresisloops, abnormal C-V curves and clockwise reversible hysteresis loops observedin barium stannate titanate ceramics, were attributed to pinning of gatheredpoint defect on domain walls.

5研究了直流电场施加和撤除引起的钛锡酸钡顺电相场诱压电谐振慢弛豫现象，认为这是同极性空间电荷注入形成空间电荷慢偶极子导致的，观察到的负压电常数证实了这个观点；研究了等温条件下阶跃电压作用下介电常数和放电电流的慢弛豫现象，发现钛锡酸钡陶瓷的铁电相和顺电相呈现不同的宏观性能时间依赖规律，认为是同极性空间电荷的输运过程导致了顺电相样品呈现强的弛豫行为，铁电相中存在畴壁捕获空间电荷的机制因而其弛豫行为较弱；研究了钛锡酸钡陶瓷中束腰电滞回线、反常 C-V 曲线和顺时针可逆电滞回线等反常现象，将其归因于点缺陷的聚集对铁电畴畴壁的钉扎作用，多次电场循环有助于解除这种钉扎状态，减弱反常特征。

It is indicated that only a single resonance peak appears in the amplitude versus frequency curve without spurious resonance peaks during the procedure. The direct actuation enables to improve the tuning accuracy, weaken the possible sample damage by the tip, and enhance the atomic force microscope bandwidth and imaging rate.

研究表明，采用压电探针的直接激振方法在探针振动的幅频曲线中仅有单一谐振峰，可以避免在压电陶瓷管激振方法下由液体振动造成的寄生谐振峰，因此使用压电探针不仅提高了探针振动频率的控制精度，而且减小了针尖对样品的损坏，还提高了仪器的带宽和成像速度。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。