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The low-level wind field displayed cyclonic character on the north part of the squall line, whereas on its south part the wind field pattern was anticyclonic, with clear convergence of westerly and southeast inflows in between.

飑线不同位置的水平风场结构有很大不同，在飑线北端，低层是气旋性辐合风场，飑线南端是反气旋性辐合风场，而中部沿强对流窄带的前部是偏西和东南风的风场辐合。

Both theory and practice analysis illustrate that stronger divergence field results from uneven distributed horizontal wind field on the right when high level current axis slopes. Owing to convectional wind convergence at low level responds to high level divergence and leads to storm.

理论和实际分析均表明：高空急流轴一旦发生倾斜，则由于其出口区水平风场的分布不均匀势必会在倾斜急流轴出口区的右侧产生较强的辐散场，由于对流风的作用，低层辐合必然会对高层辐散产生响应，诱发暴雨发生。

Methods:We built a modified synoptophore,including a refractive frame with a semireflective mirror.AC/A ratio of 23 emmetropia volunteers were measured.

调节性辐辏的量与引起该辐辏的调节变化量之比称为调节性辐辏与调节的比率(accommodative convergence/accommodation，AC/A)。

And the perfect Q-vector was applied to diagnose a heary rain process for August 3～5, 1996. The results showed that there were more advantageous using the perfect Q-vector, and suggested that the perfect Q-vector could clearly reveal the system development of the heary rain; the divergence center or line, the divergence field and the frontogenesis function field of the perfect Q-vector could be used to locate the heary rain area; the center magnitudes of the perfect Q-vector divergence field and the frontogenesis function field could be signified the intensity of the heary rain.

结果表明，完全Q矢量能较清楚地揭示暴雨天气系统的演变；考虑了湿过程的完全Q矢量在暴雨的诊断过程中显示了其更大的优越性；定性而言，完全Q矢量散度的辐合中心或辐合线、散度场和锋生函数场有助于确定暴雨的落区，暴雨区正好落在低层完全Q矢量散度场辐合中心和锋生函数场正值中心之间；定量而言，低层完全Q矢量散度场辐合中心和锋生函数场正值中心大小对暴雨强度有显著的指示作用。

Numerical tests are also conducted to investigate the microphysical effects to the mesocale convective systems. The evaporation of raindrops can strengthen the surface "cold pool" to decease the temperature of rainfall center. The condensation of vapor can lower the air pressure and increase the convergence and updraft so that the convective echo develops stronger. The melting of graupel can cool the air to restrain the convective activity. The falling of precipitation particles can increase the downdraft and induce the outflow nearly the surface. The effect of condensation is the most important among all the microphysical processes. It can change the whole structure of cloud system.

微物理过程对对流系统发展和维持有重要作用：强降水的雨滴蒸发过程会加强"冷池"效应，同时增强了雨带南侧原有的地面中尺度辐合线；凝结潜热在低层诱发了与回波相应尺度的中尺度低压，增强了辐合和上升运动，促进对流发展；霰的融化吸热通过冷却大气会不利于气压下降、气流辐合抬升等过程，降低对流不稳定能量，减缓对流发展；重力拖曳使气块冷却降温，降低对流不稳定能量，并且使低层的气压升高、气流辐散，在近地面附近产生出流，加强地面中尺度辐合线的强度。

The results suggest that the squall line occurred under the favorable weather conditions.

结果表明：飑线是在有利的天气形势下发生的，飑线上强风暴的强度大、高度高；飑线速度剖面图中显示有低层辐散、中层辐合、高层辐散的特征；垂直累积液态水含量迅猛增加到比较大的数值对冰雹预报有很好的指示意义；在冰雹指数产品中以强冰雹概率大于30%作为冰雹预警门限则有较好的效果；边界层辐合线起到了触发对流和加强对流的作用。

Convergence is stronger than divergence in the Polar Front Zone,indicating that a part of the converging water must come from the cold water transporting northward from south of PFZ and contribute to the formation and maintenance of the lateral temperature gradient of SAF.

极锋区(PFZ，指极锋PF与亚南极锋SAF之间的区域)中辐聚大于辐散，部分辐聚的水体必定来自极锋以南向北输送的温度更低的上层水，对SAF水平温度梯度的形成和维持做出贡献。

In the initial stage, the convergence of the low layer was stronger than that of the upper layer of the boundary layer, and the rotation of the boundary layer flow was weak, so a convergence line of the boundary layer was one of important factors to trigger convection.

MCS初期边界层低层的辐合强于边界层高层辐合，边界层气流旋转作用较弱，边界层辐合线是对流触发的重要因素之一。

The flow field construct of meso-β cloud clusters which bring the heavy-hard rainfall in northeast plateau is that the low level cloud cluster is located in the south of converging region, the southern low level influx converged in the cloud cluster and have some affection on the setting up of the rainstorm in the low level. In the middle level, the cloud cluster is lied in near the westerly trough and the southwest airflow ahead of the trough constantly transmits water vapor to the cloud cluster. In the high level, there are a pair of high and low pressure centers around cloud clusters and are obvious divergence airflow, and there is weak ageostrophic high level outflux along pressure force.

产生高原东北部地区大到暴雨天气过程的中—β尺度云团的流场结构特征是：在低层，云团位于辐合区的南部，低层的偏南低空入流在云团内辐合，对大到暴雨的形成有一定的作用；在中层，云团位于西风带低槽附近，槽前的西南气流不断地给云团输送水汽；在高层，云团附近有一对高、低压中心，为明显的辐散气流，沿气压梯度力方向有强度不强的非地转高空出流。

The severe storms on the squall line had large radar reflectivity and high tops of echoes. There was a divergence at lower level, a convergence at middle level, and a divergence at upper level in the velocity cross section of the squall. The VIL (Vertical Integrated Liquid water) of the storms increased rapidly to a large value, which is a good indictor of hailstorm. When the probability of severe hail is larger than 30% according to the hail index products, a hail storm is very likely to happen. The convergence line in the boundary can trigger and intensify convections.

结果表明：飑线是在有利的天气形势下发生的，飑线上强风暴的强度大、高度高；飑线速度剖面图中显示有低层辐散、中层辐合、高层辐散的特征；垂直累积液态水含量迅猛增加到比较大的数值对冰雹预报有很好的指示意义；在冰雹指数产品中以强冰雹概率大于30%作为冰雹预警门限则有较好的效果；边界层辐合线起到了触发对流和加强对流的作用。

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。