The results showed : ( 1 ) peer group in 4-5 th graders was still in the initial formation stage, its density and centralization kept increasing with grade;
结果表明：（1）同伴团体在小学四、五年级尚处于初步形成期，其密度和中心势均随年级升高而提高；
The experimental studies demonstrated that reasonable abrasive and hardness grade of wheel, grinding parameter, high efficiency grinding fluid and CBN wheel will avoid effectively th...
试验研究表明，合理的砂轮磨料和硬度等级、合理的磨削用量、高效磨削液和CBN砂轮将有效地避免钛合金的磨削烧伤和磨削裂纹。
The experimental studies demonstrated that reasonable abrasive and hardness grade of wheel, grinding parameter, high efficiency grinding fluid and CBN wheel will avoid effectively th...
试验研究表明，合理的砂轮磨料和硬度等级、合理的磨削用量、高效磨削液和CBN砂轮将有效地避免钛合金的磨削烧伤和磨削裂纹。
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