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SiO vapor is an important precursor for both carbonthermic and aluminothermic reactions. The rate-controlling step is the reaction in which SiO〓 is reduced to form SiO .

研究发现，无论碳热还原或铝热还原，SiO气体是重要的中间产物，SiO〓还原为SiO的反应是整个还原氮化过程的速度控制步骤。

A peptide antibiotics gene from Amaranthus hypochondriacus, Ah-AMP, was amplified by PCR and cloned. Sequence analysis results revealed that this gene is 261bp in length encoding a precursor polypeptide of 87 amino acid residues.

本文通过PCR技术从苋属植物千穗谷的总DNA中扩增出苋菜多肽抗生素的核基因片段，序列分析结果表明该基因长261bp，编码一个由86个氨基酸组成的Ah-AMP前体多肽。

The invention also relates to a preparation method of the selective infrared absorption material of the amino adipate with the intercalation structure, which is characterized in that hydrotalcite LDHs is taken as a precursor, and organic matter of aminoacetic acid is intercalated between the hydrotalcite LDHs layers by an ion-exchange method and then assembled to obtain the IDAs-LDHs with a good crystal phase structure and excellent performance.

本发明还涉及该氨基二乙酸插层结构选择性红外吸收材料的制备方法，以水滑石LDHs为前体，采用离子交换法将氨基乙酸类有机物插入到LDHs层间，组装得到晶相结构良好、性能优异的IDAs-LDHs。

Precursors of sulfates and alkali halides prepared in co-deposition process were mixed homogenously, annealed at high temperature and then formed CoO and NiO fibers, XRD, XPS, Raman and SEM were used to characterized the samples, the growth of these fibers might be a special LS mechanism: soluble precursors in molten salt decomposed gradually to form initial crystal nucleus and succeeding particles adhered to these nucleus and grew anisotropically in the special high temperature fluent medium, the higher decomposition temperature and solubility of the precursor are two key factors in this method, which are in favor of a longer growth process and result in larger sizes of the final metal oxides crystals.

以共沉淀方法生成硫酸盐与碱金属卤化物融盐的均匀混合前驱物，在高温下退火制备出了CoO和NiO的晶须，以XRD和XPS等对成份进行了分析，SEM分析了形貌特征，研究了不同前驱物热分解特性，认为本方法是一种简单的LS生长机制：可溶性前驱物于融盐中热分解后逐渐析出成核，后续的粒子附着在核上，在融盐环境下沿一定方向作准一维生长，其产物形貌之不同源于硫酸盐的高分解温度和在融盐中的可溶性，导致晶体生长过程中成核过程与生长过程竞争的结果对一般前驱物结果的偏移。

A new synthesis method for 15NL-tryptophan by yeast fermentation using glucose as carbon source, ammonium sulphate as nitrogen source, and 15N anthranilic acid as a precursor is described.

以葡萄糖为碳源，硫酸铵为氮源，15N邻氨基苯甲酸为前体物，利用酵母发酵合成15NL-色氨酸，是合成15NL-色氨酸的一种新方法。

Tumor cells change: As the cytoplasm of the increase in core protein precursor mostly basophilic.

瘤细胞胞浆的改变：由于胞浆内核蛋白体增多而多呈嗜碱性。

In our study, polyimide hybrid films containing bimetalic compounds were prepared by codoping poly with a bariumand titanium precursor prepared from Ba(CH_3COO)_2, Ti_4, and acetic acid followed by casting and thermal curing.

陶瓷粉BTL是由Ba(CH_3COO)_2，Ti_4和乙酸制成的钡钛前驱物，采用溶胶凝胶法合成，并由红外光谱和X-射线衍射图证明，在650℃BTL完全转化为BaTiO_3晶体。 3。通过两步法合成含陶瓷粉的聚酰亚胺复合材料。

Through theoretical analysis of bischofite＇s pyrolysis and chemical analysis of intermediate products during different sintering stages, anhydrous magnesium chloride was presumed to be the precursor, which was confirmed by the preparation of MgO whisker from anhydrous magnesium chloride.

通过对水氯镁石热解的理论分析、以及对灼烧各阶段产物的化学分析，确定生成晶须的中间产物为无水氯化镁，然后直接从无水氯化镁制备出MgO 晶须。

Linked quadrilateral pyramid and hexangular pyramid as a precursor nucleus,two new microcrystals of silver bromoiodide were prepared.

本文研究了用连体四角锥碘化银为晶核制备类似于四面体碘溴化银微晶和用六方角锥碘化银为晶核制备片状碘溴化银微晶的方法，并对两种不同微晶的结构，形态和性能进行了比较和分

He first synthesis of the precursor 45b of Tuxpanolide was accomplished fromβ-alkoxy aldehyde and β-acetoxy-γ-butyrolactone by the Aldol reaction.

uxpanolide的合成前体45b的首次不对称合成：以β-烷氧基开链醛和β-乙酰氧基-γ-丁内酯参与的Aldol醛醇缩合反应首次得到了前体化合物45b。

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％。