绿宝石

我家养着一盆花叫绿宝石，也叫绿萝。绿宝石的叶子从远处看，只有一条叶脉，叶柄是心形的。从近处看，绿宝石其实有许多条叶脉。一盆绿宝石有好几颗围着中心的一个柱子，长在花盆里。绿宝石刚刚长芽时叶子是嫩绿的，卷着很小。但是它会越长越大，颜色也变的越来越深。

Machining of Single‑Crystal Sapphire with Polysaccharide‑Bonded Abrasive Tool

A novel polysaccharide-bonded abrasive tool is proposed for the green machining of single-crystal sapphires.The prescription and manufacturing process of the proposed tool is designed,and the gelation property of polysaccharide by microwave treatment is investigated.Abrasive tool samples are fabricated,and a machining experiment on a single-crystal sapphire is performed.It is found that the crystallinity of polysaccharide gel decreases as the proportion of cross-linked polysaccharide increases.Abrasive tool samples with cross-linked polysaccharide present higher surface hardness.With the new abrasive tool,the surface quality of sapphire wafer can be significantly improved.This new tool with an abrasive to binder ratio of 2∶1 attains a material removal rate of 0.68μm/min.It is found that increasing the abrasive to binder ratio leads to better self-dressing performance but worse material removal ability and greater loss of abrasive tool materials.The validity of polysaccharide as an abrasive tool binder is preliminarily verified.

狂想曲乐队

Rhapsody（狂想曲）是90年代意大利的著名速度金属乐队。创始人Luca Turilli爱巴洛克风格影响，迷恋欧洲中古传奇文化和勇士传说，因此在词曲上别具一格。乐队键盘手Alex Staropoli精通古典音乐。