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The main results were as follows:There was significant correlation between the soil urease and phosphatase activities, which showed no significant difference upon different plots. The urease and phosphatase activities in the soil were higher in spring than autumn, which under mangrove plants were all higher than those in the New alluvial soil without plants and Bared land. Soil urease activity exhibited no significant difference under different mangrove species. The phosphatase activity in the soil of Centenary Aegiceras corniculatum and Spartina alterniflor was the highest, which was the higher in the soil of Kandelia candel and Avicennia marine.

结果表明：土壤脲酶和磷酸酶活性存在极显著的相关性；两种酶在不同区域间均无显著差异，季节变化均表现为春季大于秋季；有红树植被的土壤脲酶和磷酸酶活性皆大于空地和裸地，土壤脲酶不同红树植被下无显著差异，磷酸酶则表现为百年生桐花树和互花米草显著高于其余植被，秋茄和白骨壤次之。

N,N′-Disubstituted ureas,used as intermediates for synthesis of pesticides,resin precursors and carbamates,were synthesized from carbon dioxide and primary amines(namely n-propylamine, n-butylamine ,n-amylamine,n-hexylamine,benzylamine and aniline) over organic base catalysts.

以正丁胺为反应基质、TBD为催化剂，合成N，N′-二丁脲的最佳反应条件为：反应温度180℃，CO2压力10.0M Pa，反应时间10h，TBD摩尔分数5.0%；在此条件下，N，N′-二丁脲的收率为81.8%；红外光谱表征结果表明，合成的产物为N，N′-二丁脲。

Three new kinds of thiourea - type chelating cotton cellulose, thiourea cellulose, thiosemicarbazide cellulose and diphenylthiourea cellulose, were synthesized in our Lab, and their absorptive characteristics for copper was investigated.

将自制合成的三种新型硫脲型螫合纤维素——硫晚棉纤维，氨基硫脲棉纤维和二苯硫脲棉纤维应用于钢的吸附性能的研究，采用火焰原子吸收法测定选择了吸附和解吸的最佳条件。

The experiment selected a slow release fertilizer and studied the best dosage proportion of the slow fertilizer, dipotassium hydrogen phosphate, DCD as an inhibitor.

对几种有机脲酶抑制剂的抑制效果研究表明，一定浓度的游离态草炭土腐植酸和风化煤腐植酸，对土壤中脲酶活性都有较好的抑制作用，都是良好的有机脲酶抑制剂。

The purpose of this thesis is just to search a novel synthesis of thiourea, and to use thiourea in dealing with the waste water from the production of phthalic anhydride, and the application of thiourea in solid-state reactions at low heating temperature was also studied.

本论文研究的目的就是寻找一种合成硫脲新的工艺过程，且尝试以合成得到的产物硫脲应用于工业苯酐废水的处理，同时对硫脲在低热固相化学中的应用进行了初步的探索。

The obtained terephthalaldhydic acid semicarbazone has such advantages as simple process and high purity (above 99% after post treatment), and can be used as standard in enzymoimmunoassay of semicarbazide.

本发明成功合成了呋喃西林代谢物氨基脲的衍生物氨基脲缩对醛基苯甲酸，合成步骤简洁，经过后处理，纯度高达99％以上，完全可以用作标准品，为以后人们对氨基脲的酶联免疫检测研究提供了方便的途径，可以满足国内对其研究的需要。

The best technology conditions have been decided through experiment of sulfourea dioxide synthesized by sulfourea and hydrogen peroxide.

由硫脲和双氧水合成二氧化硫脲，通过试验确定了最佳工艺条件，使二氧化硫脲的收率均在 85%以上，并对母液回收进行了研究，使其收率均在 90 %以

This paper prepared three types of Uron resin according to different kind of synthesis processes, and then obtained several mixed urea-formaldehyde resin sby mixing Uron resins with normal UF resins at different experiment conditions.

以不同工艺制备了三种含尤戎结构的脲醛树脂，通过其与普通脲醛树脂的混合制得多种混合脲醛树脂。

Straw returned to field played a positive role in increasing soil insect communities with the largest contribution, primarily the amounts of individuals and dominant species of macro and meso/micro soil animal, especially Neanuridae and Isotomidae animals individual amounts increased by nearly 10 times.(3) Soil nutrien had a positive correlation with soil bacteria, azotobacter, ammonifying bacteria, cellulose decomposing bacteria and denitrifying bacteria. Straw returned to field could stimulate effective microorganisms growth and population quantity in the soil. The increase of microbe community amount is 15%~44% more than that of CK.(4) Soil nutrien had a positive correlation with soil phosphatase, urease and sucrase activities, and a negative correlation with catalase.

研究发现：(1)长期配施秸秆能提高土壤速效氮、磷、钾含量，平均分别提高15%、48%和22%；(2)配施秸秆对土壤昆虫群落呈正向作用且贡献最大，主要增加了大型、中小型农田土壤动物的个体总数和优势类群数量，尤其是疣跳科和等节跳科动物个体数量增加近10倍；(3)土壤养分与土壤细菌、固氮菌、氨化细菌、纤维分解菌和反硝化细菌呈正相关，秸秆还田激发土壤有益微生物的生长和类群数量，使土壤微生物类群数量比对照增加15%~44%；(4)土壤养分与土壤磷酸酶、脲酶、蔗糖酶活性呈正相关，与过氧化氢酶呈负相关，秸秆还田增强土壤蔗糖酶、磷酸酶和脲酶活性，特别是脲酶和蔗糖酶活性平均提高26.5%。

The determination of buffer capacity of urea-formaldehyde resin used in MDF is discussed.

探讨中密度纤维板用脲醛树脂缓冲容量的测定，并分析影响脲醛树脂缓冲容量的因素，脲醛树脂缓冲容量对其固化时间和压制中密度纤维板性能的影响。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。