▎ 摘　　要

NOVELTY - Regulating chromium distribution and shape of lawn compost substrate by using carbon nanotubes comprises (i) taking test waste compost from Tianjin Xiaodian living waste composting plant, sieving, taking graphene microchip, graphene oxide, carboxylated multi-walled carbon nanotubes and hydroxylated multi-walled carbon nanotubes, and (ii) planting Festuca arundinacea, filling the bottom of each PVC pipe with sand, then filling the top layer with municipal solid waste compost and carbon nano material to form mixed matrix of compost and nano material, and determining the related indexes. USE - The method is useful for regulating chromium distribution and shape of lawn compost substrate by using carbon nanotubes for improving the transformation of heavy metals into biologically unusable state in the matrix, and transformation of chromium to biologically unusable state (all claimed). DETAILED DESCRIPTION - Regulating chromium distribution and shape of lawn compost substrate by using carbon nanotubes comprises (i) taking test waste compost from Tianjin Xiaodian living waste composting plant, and sieving through 2 mm sieve, selecting Gramineae plant F. arundinacea from northern China, taking graphene microchip having microchip size of 0.5-20 mu m, microplate thickness of 5-25 nm, specific surface area of 40-60 m2/g, density of 2.25 g/cm3, conductivity of 8000-10000 S/m, and carbon content of more than 99.5%, taking graphene oxide having average thickness of 3.4-7 nm, slice diameter of 10-50 mu m, 5-10 layers, 100-300 m2/g specific surface area, and purity of more than 90%, taking carboxylated multi-walled carbon nanotubes with diameter of 20-40 nm, length of 10-30 mu m, carboxylic acid (-COOH) content of 1.43%, purity of more than 90 wt.%, ash content of less than 8 wt.%, specific surface area of more than 110 m2/g, and conductivity of more than 102 s/cm, and taking hydroxylated multi-walled carbon nanotubes having diameter of 20-40 nm, length of 10-30 mu m, hydroxy group (-OH) content of 1.63%, purity of more than 90 wt.%, ash content of less than 8 wt.%, specific surface area of more than 110 m2/g, and conductivity of more than 102 s/cm, and (ii) (a) planting Festuca arundinacea at a height of 25 cm, taking PVC pipe having diameter of 5 cm, sealing the bottom of the pipe with double layer gauze, setting a control group (CK), where the control group is not added with carbon nano-materials, and then respectively adding graphene (G), graphene oxide (GO), carboxylated multi-walled carbon nanotube (C-CH) and hydroxylated multi-walled carbon nanotubes (C-OH) to experimental group, and (b) filling the bottom of each PVC pipe with 30 g sand, then filling the top layer with 400 g municipal solid waste compost and 1% (wt./wt.) carbon nano material to form mixed matrix of compost and nano material, uniformly mixing the carbon nano material and compost, and placing into the pipe, allowing to stand and curing for 7 days, during the curing period, maintaining the soil water holding capacity by watering, and curing the cultivation of tall fescue, where sowing amount is 0.2 g/cm2, and (c) maintaining room temperature at 18-25 degrees C and relative humidity of 35-65% during culture period, maintaining the light for indoor light into the room to 6856-27090 LX, frequently exchanging the positions of the basin in order to ensure consistent light, supplying water daily to ensure the necessary water for plant growth, co-culturing for 130 days, 70 days cutting, and measuring the relative index. An INDEPENDENT CLAIM is also included for use of hydroxylated multi-walled carbon nanotubes to regulate the high fescue green degree of the compost substrate for increasing the chlorophyll content of tall fescue, where the chlorophyll is chlorophyll a, chlorophyll b and total chlorophyll.