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This is now a major presence in the real estate industry.

这是现在房地产业存在的一个最主要的问题。

This paper has studied the esterification of isopropanon and salicylic acid in the presence of boronic acid.

以硼酸为催化剂合成水杨酸异丙酯，发现硼酸对水杨酸异丙酯的合成具有良好的催化活性。

The anti-noise performance of the improved method is also investigated in this paper,and the variance equation of the frequency estimation error in the presence.

分析了改进方法的抗噪声性能，推导出了在高斯白噪声背景下频率估计误差的方差公式，并通过仿真计算验证了推导公式的正确性。

In multiple regression analysis in the presence of latewood percent, estimative efficience don't increase with the number of ...

所以，不能以树木常用测定性状如胸径、树高和年龄来预估胸高木材密度。

The results of derivatization indicated that the derivatives can be obtained by the labeling reaction of EASC with estradiol (E2) and estriol (E3) in the presence of NaHCO3 buffer (pH 10.5) at 60℃ for 3 min. The excitation wavelength λ(subscript ex and emission wavelength λ(subscript em were 270 nm and 430 nm, respectively.

EASC与E2和E3在NaHCO3缓冲液(pH10.5)中，于60℃下反应3min即可获得稳定的荧光产物，最大激发波长λ(下标 ex和最大发射波长λ(下标 em分别为270nm和430nm。

In presence of this catalyst,ethanolamine reacted with alkali water at 140-170 ℃ and H2 pressure of 0.8-1.2 MPa.The conversion was over 98% and selectivity for glycine was higher than 95%.

实验结果表明：在温度140170 ℃，H2压力0.81.2 MPa，一乙醇胺与碱水催化反应，其转化率可达98%以上，甘氨酸的选择性高于95%。

The results show that these derivatives can be obtained in the yield of over 90％ in the presence of DMF when using ethyl acetate as a catalyst.

结果表明，以N，N-二甲基甲酰胺为溶剂，以乙酸乙酯为催化剂的合成路线，均可以以90％以上的得率合成出上述化合物。

It is shown from the analytical results that in the depressed rats' brain, the contents of homovanillic acid, noradrenaline, dihydroxyphenyl ethylamine and 5-HT increase in the presence of the saikosaponin A. These results can help to clarify the mechanism of saikosaponin A in curing the depression.

实验结果表明，柴胡皂苷A可使抑郁型大鼠脑中的高香草酸、去甲肾上腺素、多巴胺及5-羟色胺的含量升高，这一结果有利于对柴胡皂苷治疗抑郁症的物质基础及相关机理进行更深入了解。

From 3-chloropropene bycondensation with sodium ethylate in ethanol to form 3-ethoxypropene followed by anti-Markovnikov addition with HBr inthe presence of benzoyl peroxide.

3-氯丙烯与乙醇钠在乙醇中回流制得3-乙氧基丙烯，继而在过氧苯甲酰存在下，与溴化氢经反马氏加成制得1-溴-3-乙氧基丙烷，总收率89。

In the presence of the upwelling, the EUC meanders along the zonal direction,with its core diving down to 300m depth at the west side of the upwelling and rising up to 100m depth at the east side.

由于该上升流的存在，使赤道潜流沿纬向发生弯曲：位于上升流西侧的潜流流轴降至300m水层深处，而东侧上升至100m左右的水层深处。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。