The earthwork composite material of long life and low cost provides the method for solving material ageing problem in the engineering. 长寿命、低造价的土工合成材料为解决工程中的材料老化问题提供了解决方法。
We have succeeded in making a kind of phase change material ( PCM) of high thermal storage density, good corrosion-resistant performance and low cost of preparation by powder sintering method. 本研究采用粉末烧结工艺将陶土分别同性能优良的高温熔融盐复合,成功地制备出蓄热密度高、耐腐蚀性好且成本低廉的相变蓄热复合材料。
But the one step method that taking propene and hydrogen bromide as material synthesized 1-bromopropane was low cost, obtaining high-purity product, and it's production process has no pollution to environment. One step method be deemed to the optimum method. 而以丙烯和HBr气体一步直接合成1-溴丙烷的方法成本较低,所得产物纯度较高,且其生产过程对环境是绿色的,可以说是生产1-溴丙烷的最佳方法。
This article introduces the new method of producing n-amyl aldehyde with 2-butene as raw material and Fe-Co as catalyst via oxo reaction. It can decrease the cost comparing with the method of using noble metals Co or Rh as catalyst. 文中介绍了以2-丁烯为原料,用铁钴簇催化剂羰基合成法制正戊醛的新方法,与用贵金属铑、钴催化剂法相比,可降低产品成本。
These questions make the stainless steel material excellent industrial properties cannot to be wide application in industry, so the study of high efficiency, high quality and low cost of stainless steel materials processing method and technique is seemed particularly important. 这些问题导致了不锈钢材料的优良特性在工业上难以得到广泛应用,因此研究高效率、高质量、低成本的不锈钢的加工方法显得尤为重要。
The construction project cost involves many elements, include labor costs, machinery costs and material cost, etc., so firstly ABC classification method is adopted to analysis main elements of the construction cost and distinguish priorities and general objects. 由于市政工程成本涉及到很多方面,包括人工费、机械费、材料费等,故引入ABC分类法对工程成本组成要素进行分类排列,分清重点和一般,从而有区别地确定控制的重点对象。