optional是什么意思

用法例句

Although the 2-choosable graphs have been fully classified in [2], the 3-choosable graphs have not been classified yet, even if 3-choosable bipartite graphs.

目前 ,所有 2 -可选[的]图在 [2 ]中已给出 ,但对 3-可选[的]图 ,即使是对 3-可选[的]二部图的分类仍未完成 。

Study on beneficiability of Nb-Ta ores in Ray Nb-Ta Mine;

Ray铌钽矿可选性试验研究

Aiming at the problem of high sulfur grade of iron concentrate in Gangcheng Mining Company, test study was carried out on the ore beneficiability, the choice of the adjusting agent, the contrast of the flowsheet.

针对钢城矿业公司铁精矿硫指标高的问题,进行了矿石的可选性、调整剂的选择、流程的对比等试验,得出了氟硅酸钠替代硫化钠的活化浮选法和浮—磁—浮的选别方案,并成功应用于实际生产,解决了3012#矿石的难选问题,使铁精矿硫由0。

The coal-petrological interpretation about the difference in washability of coals seams No.4-1 and No.11 of Antaibu opencut in Pingshuo mining area;

运用煤岩学研究平朔安太堡露天矿4-1号与11号煤层可选性差别的原因

The research work consists of two aspects:the relationship between fluorine in coal and ash,mineral composition;organic affinity and washability of fluorine in coal.

研究内容包括:煤中氟与灰分、矿物成分之间的关系;煤中氟的有机亲和性与可选性;研究结果表明:煤中氟质量分数与灰分质量分数之间呈正相关关系;中国煤中氟质量分数与灰分之间存在以下指数增长关系;煤中氟质量分数与煤中矿物质的成分有关;煤中氟属“中等无机型”元素,无机亲和力较强,有机亲和力较弱;煤中氟以无机氟为主,有机氟为辅的方式赋存;原煤洗选是脱除煤中氟的一种可行的技术措施。

The paper deals with some factors effecting on coal washability and taking the difficult-to-wash coal extracted from No.

介绍了影响煤可选性的因素 ,并以乌达矿区难选煤层 1 5煤层煤为例 ,对其中的黄铁矿和粘土矿物的赋存状态作了讨论 ,分析了其可选特

The preliminary experimental research on preparability was carried out for iron ore in a certain iron mine.

对某铁矿进行了可选性试验研究,初步确定了矿石勘探矿样主要成分的选矿方法和可能达到的指标,进而确定了矿石的加工工艺、合理流程和技术经济指标。

On the basis of analyzing characteristics and preparability of raw coal of Baijiazhuang Coal Mine, a technical flowsheet of dry coal preparation with an air dense medium flui dized bed is decided, which is suitable for raw coal property.

通过对白家庄矿干法选煤厂原煤的煤质分析及可选性分析 ,制定了该厂适合原煤特点及市场要求的空气重介流化床干法分选加工工艺流程 ,总结了该工艺流程的主要特点 ,证明了该工艺的简单、高效、可靠及干法选煤的发展前