查询词典 practical chemistry

The results show that single sample analysis is better to reflect the distributed features of soil geo-chemistry,the economical and practical sampling density is 16-32 points per km2(100ha),and the geo-chemical map-making is better with the help of inverse distance interpolation.

结果表明，单样分析能更真实地反映土壤地球化学的分布特征，经济实用的采样密度为16点/km2～32点/km2(100ha)，地球化学图件编绘以距离倒数插值法成图效果更好。

Isomorphous substitution of heteroatoms, especially transition metals for Si or Al in zeolite frameworks is an important way to modify the zeolite properties for practical applications, which has achieved considerable interest in the field of zeolite chemistry.

近年来，杂原子分子筛的研究受到普遍关注。杂原子引入分子筛不仅可以有效地调变分子筛的结构和表面性质、赋予分子筛新的催化性能，而且可能得到新型的分子筛材料。

All the compounds were isolated and identified from the bituminous coals for the first time, bis(2-ethylheptyl) terephthalate and 18-ethyl-17-(hexan-2\'-yl) docosanoic acid are new compounds.Further more, a Colourless Oil Liquid, a white acerate crystals containing some alkanes, a white tabular crystals consisting of some fatty acid esters and a white powder crystals in which some fatty acids exist were isolated and analysed by GC/MS for the first time.Through this research, a study method of"classification extract of bituminous coal- separation with silica-gel and gelatin column chromatographies- identification of the isolated compounds by FTIR, GC/MS, LC/MS, 1H NMR and 13C NMR analyses"was established and proved to be a practical approach toward separable and non-destructive identification of some organic compounds in bituminous coals for coal chemistry research.

本研究建立了&原煤分级萃取-硅胶与凝胶柱层析分离与纯化-GC/MS或LC/MS检测-FTIR、MS、1H NMR和13C NMR波谱解析&这一煤中有机化学成分的非破坏性分离与分析的研究方法，并验证该研究方法有效可行。

A boiler water controlling system with basifier a mg/L Na3PO4+b mg/L NH3+c mg/L NaOH is investigate in the paper. Several calculate methods are discussed and the precision pH value calculating equation is proposed for a cycle chemistry system that has seven changing parameters coexisting together, i. e. a mg/L Na3PO4+b mg/L NH3+c mg/L NaOH+d mg/L H2SO4+e mg/L CH3COOH+f mg/L CO2+g mg/L SiO2. As an example of equilibrium phosphate treatment, the pH value are obtained and showed in graphics with the four kinds of impurity changing from 0 to 1.0 mg/L. The calculating results can be used in practical boiler water pH value control.

对于一个采用a mg/L Na3PO4+b mg/L NH3+c mg/L NaoH碱化剂的炉水控制体系，主要讨论在炉水中存在d mg/L H2SO4+e mg/L CH3COOH+f mg/L CO2+g mg/ L SiO2 4种杂质时炉水pH值的计算方法，得到通用的pH值计算表达式；并以炉水平衡磷酸盐处理工况为例，计算这4种杂质在0-1 mg/L变化时，其单独或联合作用对炉水pH值的具体影响程度，以6幅图形展示计算结果，该结果可应用于炉水pH值的实际控制。

Through one year continuous observation the water chemistry,the seasonal,annual changes of water chemical composition and hydrochemistry type were mastered.which has important scientific significance on Chemical composition of groundwater and river water sources and changes regulation,as well as chemical characteristics of water,This research has practical significance on thescientificly and rationally development and utilization of local water resources and tourism reseo...urces and environmental protection.

通过对该地区水化学成分连续的观测。可以查明翠华山和少陵塬地区河水与泉水化学成分的季节变化、年变化及其水化学类型等，这对揭示该区地下水与河水化学成分来源与变化规律以及水化学特征有重要科学意义。

In so far as these writings contain references to the devices and methods of experimental chemistry, these earl alchemists allude to just such practical operations as we have seen in the Egyptian papyri from Thebes, although they are rarely so definite and clear as the latter descriptions and directions, and are mingled with a confused mass of obscure allegorical narratives and descriptions.

至于这些著作含有提到发明物和实验化学的方法，这些早期的炼金术士提到的就是这种实际运用，如同我们已经在来自底比斯papyri看到的那样，虽然它们是与后来的描述和指导罕有的明确和清晰，而是混合令人困惑不解大量晦涩的寓言叙述和描述。

Metal phosphonate coordination polymers have attracted a great deal of research interest due to their structural diversities and many potential and practical applications in catalysis, ion exchange, intercalation chemistry, absorption, proton conduction, and so on.

金属有机膦酸配位聚合物因其结构上的多样性以及在离子交换、嵌入材料、吸附材料、质子导电材料和催化材料等领域具有潜在的应用前景，已引起人们的广泛关注。

Sanitary Chemistry is a actual practicing science, so during the teaching, several aspects should be specially noticed: theories should be bent with practicing, operating in person should be advocated, instruments should be operated correctly and students should build up scrutinously and precisely scientific attitude as well as practical and realistic style of study.

它是一门实践性很强的学科，教学中应注意理论联系实际，提倡亲自动手操作，正确使用各种分析仪器，同时培养学生严谨的科学态度和实事求是的学风。

In addition, there were social and intellectual difficulites, chemistry is nothing if not practical.

此外，还有社会和知识的原因。

The writer carries on the related theories of the problem situation to study the big case foundation well up, with the situation cognizes and studies a class of theories for leading, and have three stages to launch to practical research; The first, the research into big case strategy of problem situation and the process of tiding up some materials in the chemistry teaching.

笔者在对问题情境的相关理论进行研究的基础上，以情境认知与学习理论为指导，分三个阶段展开实践研究：第一，化学教学中问题情境创设的策略研究和案例素材的整理加工，包括结合生活、生产和当前科学技术发展中的实际问题创设问题情境，从化学实验入手创设问题情境，利用化学史料创设问题情境，利用学生已有知识创设问题情境或引起学生的认知冲突等。

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。