稳定化

"It has valence 2 or 4 in compounds, including stannous chloride (used in tin galvanizing and manufacturing polymers and dyes), stannous oxide (used to make tin salts for chemical reagents and plating), stannous fluoride (used as an anticavity ingredient in toothpastes), stannic chloride (a stabilizer for perfumes and a source of other tin salts), and stannic oxide (a catalyst and a polish ing powder for steel)."

在化合物中的原子价为2和4。化合物包括氯化亚锡(用于电镀锡以及制造聚合物和染料)、氧化亚锡(制备化学试剂和电镀用的锡盐)、氟化亚锡、氯化锡(香水的稳定剂以及其它锡盐的原料)以及氧化锡(催化剂以及钢材的拋光粉)。

"It has valence 2 or 4 in compounds, including stannous chloride (used in tin galvanizing and manufacturing polymers and dyes), stannous oxide (used to make tin salts for chemical reagent s and plating), stannous fluoride (used as an anticavity ingredient in toothpastes), stannic chloride (a stabilizer for perfumes and a source of other tin salts), and stannic oxide (a catalyst and a polishing powder for steel)."

在化合物中的原子价为2和4。化合物包括氯化亚锡(用于电镀锡以及制造聚合物和染料)、氧化亚锡(制备化学试剂和电镀用的锡盐)、氟化亚锡、氯化锡(香水的稳定剂以及其它锡盐的原料)以及氧化锡(催化剂以及钢材的拋光粉)。

"It has valence 2 or 4 in compounds, including stannous chloride (used in tin galvanizing and manufacturing polymers and dyes), stannous oxide (used to make tin salts for chemical reagents and pla tin g), stannous fluoride (used as an anticavity ingredient in toothpastes), stannic chloride (a stabilizer for perfumes and a source of other tin salts), and stannic oxide (a catalyst and a polishing powder for steel)."

在化合物中的原子价为2和4。化合物包括氯化亚锡(用于电镀锡以及制造聚合物和染料)、氧化亚锡(制备化学试剂和电镀用的锡盐)、氟化亚锡、氯化锡(香水的稳定剂以及其它锡盐的原料)以及氧化锡(催化剂以及钢材的拋光粉)。

A reversible Markov process as a chemical polymerization model where a gelation transition exists is presented. The stationary distribution, partition function and expression of covariance of this model are obtained.

以存在凝胶化现象的高分子反应模型为背景，定义了高分子反应所对应的可逆Markov过程，给出了过程的稳定分布及配分函数，推导出了分子间协方差的表达式。

The results above showed:(1) The cultivars of large-flowered chrysanthemum are widely distributed in Beijing area with plentiful floral types and floral colors;(2) The cultivars with the rare types and colors are urgent for protection;(3) Most of the quantitative characters obeys to the normal distribution,some important traits agreed with skewed distribution.The probability grading can assist quantitative character in establishing new grading standards;(4) Most of qualitative characters is asymmetrical in cultivars,which might be caused by unbalanced differentiation of characters or linkages coming from emphasis characters selection;(5) The floral characters are relatively stable and have comparably large influence on classification,the characters of stipule also have a certain degree of stability and can act as an reasonable supplement for cultivars classification,but the foliar characters have worse stability and can only be recognized as lower level criterion.(6) The genetic relationship among the Flat-petaled group,the Quilled-petal group and the Spoon-petaled group are closest,which followed by the Filiform-petal group because of long-term selection pressure for the specialization of the petal tip loved by most people.The Anemone-petal group has further genetic relationship with these four groups.(7) ISSR molecular marker detection indicates that the proportion of polymorphic loci of lardge-flowered chrysanthemum is higher,in which the Flat-petaled group has the highest genetic diversity level.

综合以上的研究结果表明：(1)北京地区现有大量大菊品种，且花型与花色较为丰富；(2)珍稀花型、花色品种亟需保护；(3)大部分数量性状是符合正态分布的，少数重点观赏性状迫于选择压力呈现偏态分布，概率分级法能够辅助大菊的数量性状建立新的分级标准；(4)大部分质量性状在品种群内的分布是不均匀的，可能是由菊花性状遗传分化的不均衡性或受到选育重点性状的连锁作用而造成的；(5)大菊花部性状相对稳定，对品种分类影响较大，其托叶部分也具有一定程度的稳定性，可以作为品种分类的合理补充，而叶部性状稳定性较差，在品种分类中应作为更次一级的分类依据；(6)平瓣类、管瓣类和匙瓣类的亲缘关系最近，畸瓣类品种花瓣先端特化受到人们的喜爱，长期的选择压力使其区别于3种基本瓣型，而这四种瓣型与桂瓣类在亲缘关系上较远；(7)ISSR分子标记检测表明：大菊品种多态性位点百分率较高，平瓣类品种的遗传分化最为丰富。

Tricholoma may be a paraphyletic genus two. The collections identified as T. caligatum is a mixture. Some parts of them from France are members of T. matsutake, the other parts from North America are closed to T. bakamatsutake and T. fulvocastaneum. Tricholoma robustum and T. focale form a clade which is obviously a sister group of the stirp Subannulate. The stirp Caligata was defined as a group mainly on the basis of the predominant veil. But from the result of molecular systematic analysis, the presence of veil is not a stable character in the matsutake group. Species having symbiosis with conifers and broad leaf tree are all transformed from those whose host specificity is not strict. The phylogenetic tree based on ITS sequences resembled the tree of NJ algorithm based on cladistic coding. In the phylogenetic tree based on morphylogical characters, T. zangii and T. bakamatsutake form a clade, but it is the result of convergent evolution as suggested by molecular analyses. The distribution area of the matsutake group can be divided into six regions: middle and northern Europe region, Mediterranean region, Hengduan Mount.— Southeastern Tibet region, Northeastern China—Japan—Far-east Russia region, the Atlantic—North America region and the Rocky Mountain region. The abundance center of the matsutake group are Hengduan Mount.—Southeastern Tibet region and the Rocky Mountain region. Hengduan Mount.

松口蘑群的分子系统学研究得出的结果有：由于粗壮口蘑和羽衣口蘑明显和亚环族(Tricholoma，section subannulate)的种类是来自同一个谱系，和其它松口蘑群的种不具有最近共同祖先，因此松口蘑群是一个多系群；松口蘑群和口蘑属其他种类的亲缘关系比和蜜环菌属更接近；梭柄松苞菇和松口蘑群的差距明显小于油黄口蘑(T.flavovirens)和棕灰口蘑；口蘑属是一个多系群；鉴定为欧洲口蘑的标本明显不是一个单系群，其中一部分是松口蘑，另一部分和黄褐口蘑及傻松口蘑(T.bakamatsutake)比较接近；划分松口蘑群的标准是菌环的存在，但从分子系统学的结果来看，菌环的存在与否并非是一个很稳定的性状；和针叶树专性共生及和阔叶树专性共生均由寄主专化性不强的种类转化而来；在形态学系统发育树上青冈口蘑和傻松口蘑被聚为一个分枝，分子系统学的研究结果表明，这是趋同进化的结果；用支序方法编码作出的NJ树的结果更接近ITS序列的结果。

In this thesis, three major achievements were made in theoretical study: conditions and rules for preparing nano-powders by chemical precipitation are analyzed from the point of view of thermodynamics and kinetics, the principle, standards and experimental method for the aqueous dispersion of nano-scaled metal oxide powders were proposed and verified, mathematical model of nano-filming addition of dopants by chemical coprecipitation was established. In experimental research, nm-ZnO, nm-Bi〓O〓, nm-Co〓O〓 and nm-MnO powder with spherical shape, narrow particle size distribution and small particle size were prepared successfully, highly stable and dispersive aqueous suspensoid of nm-ZnO, nm-TiO〓, nm-Co〓O〓 and nm-MnO powder were prepared successfully and surface modification on these nano-powders was also achieved, 0-3 nanocomposite ZnO varistors with nm-ZnO, nm-TiO〓and nm-MnO respectively were prepared successfully by conventional mechanical attrition, and exhibited much better electrical properties than those of conventional varistors.

综上所述，本文在理论研究方面取得了三项成果：（1）从热力学和动力学角度推导并分析了液相化学沉淀法制备纳米粉体的反应条件和规律，（2）提出了纳米氧化物的水分散体系的设计原理、规范和通用实验步骤，（3）提出了共沉淀的数学模型和计算方法；在实验方面所取得的成果有：（1）成功制备了粒度小、分布窄、形貌对称的纳米氧化锌、纳米氧化铋、纳米氧化钴和纳米氧化亚锰，（2）成功地制备了纳米氧化锌、纳米二氧化钛、纳米氧化钴和纳米氧化锰的高稳定分散悬浮液并实现了干粉体的表面改性，（3）成功地进行了纳米氧化锌、纳米二氧化钛和纳米氧化锰对压敏电阻的0—3复合掺杂实验，试样性能远优于常规压敏电阻，为实现压敏电阻的高能高压化提供了新的方法和思路。

Our main work is as follows: the stable laser mode theory in uniform plasmas is extended to non-uniform plasma cases; the discussion of the sufficient and necessary conditions for laser self-focusing in uniform plasmas is developed to non-uniform plasma cases; a quantitative approach to judge the impact of different plasma density distribution on laser self-focusing is proposed; the evolution properties of asymmetric laser filed in non-uniform and uniform plasmas are discussed and mechanisms that symmetric channel-like plasmas can confine the laser centroid around the plasma channel axes and symmetrize initially asymmetric laser beams are proposed; the formation of solitary standing wave in moderate plasma density is studied by PIC simulations and can be explained by stimulated Raman scattering of laser beams in plasmas.

主要工作为：把均匀等离子体中激光的稳定模理论推广到横向非均匀等离子体情形；把均匀等离子体中激光自聚焦的充分和必要条件的讨论推广到横向非均匀等离子体情形；给出横向密度分布不同的等离子体影响激光自聚焦的定量判据。讨论了初始不对称的激光场在横向非均匀及均匀等离子体中的演化特性，并提出了具有对称腔道结构的等离子体箍缩激光质心和对称化初始不对称激光场的物理机制。用粒子模拟讨论了激光场在等离子体中形成孤立驻波的过程，认为前向受激拉曼散射是发生此现象的可能机制。

The main content of this dissertation includes: 1. Research on the theory of ultrasonic power supply, introduce its development process. On the basis of these, fix on the scheme of medical ultrasonic low-power supply. 2. According to the principle of modularized design, divide medical ultrasonic low-power supply into four parts. They are power amplify circuit, power control circuit, frequency automatic tracking circuit and matching circuit. Separately research on their theories and design their circuits and necessary programs, especially, effectively resolve the problem tracking the supersonic vibration system with a narrow syntony frequency bandwidth and a high swing. 3. The matching experiments gain good result, and prove that medical ultrasonic low-power supply is entirely up to the mustard on intellectualization, wide band of working frequency, steady output and high efficiency.

本文工作的主要内容包括： 1、研究了超声功率电源的原理，并回顾了它的发展过程，在此基础之上确定本文医用小功率超声电源的设计方案； 2、按照模块化的设计原则，将医用小功率超声电源的设计分解为功率放大电路、功率控制电路、频率自动跟踪电路和匹配电路等四个部分，分别研究了各部分的原理，在此基础之上进行了具体的电路设计和程序设计，尤其是有效地解决了对谐振频率带宽窄振幅高的超声振动系统的频率跟踪问题； 3、通过与超声振动系统的各项配合实验，取得了很好的实验结果，验证了医用小功率超声电源完全满足智能化、工作频带宽、输出功率稳定、输出效率高的设计要求。

The radar-computer integration way in the design makes it take the advantages of small size, stable and reliable.

样机采用雷达—计算机—体化设计，使样机具有体积小、稳定、可靠等优点。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。