Oxygen precipitation in conventional heavily B-doped Czochralski (CZ) silicon (HB-Si) and heavily Ge-B codoped CZ silicon (Ge codoped HB-Si) subjected to single step annealing at 650～1150℃ for 64h or low-high two step annealing(650℃/16h+1000℃/16h and 800℃/4～128h+1000℃/16h) are comparatively investigated.
Ultrafine α Al 2O 3 powders were prepared via a novel two step calcining method XRD analysis showed that the as synthesized powders were α phase, the sizes of the powders were observed about 80～100nm with regular morphology through TEM analysis
经由二步煅烧法制备了超细α Al2 O3 粉 X R D 分析说明所制备的粉是α相， T E M 观察到其一次粒子尺寸在80 ～100nm 间， 形貌较规则
A "two step" method for separate control of nuclei generation and crystal growth under different conditions was used for the synthesis of a series of ZSM-11 zeolites having SiO_2/Al_2O_3 ratios of 20 to 3400. In the case of "one step" method, the SiO_2/AJ_2O_3 value of the products from the same reaction mixture was confined within the range of 30—320。
Acetylated-hydroxylated phosphatide was prepared by acetylation and hydroxylation via two step reaction, the optimum reaction conditions were as follows: m(phosphatide) 5 g, V(n-hexane) 100 mL, acetic anhydride/phosphatide(mass ratio) 3.5%, 30% hydrogen peroxide/phosphatide(mass ratio) 11.6%, reaction temperature 6070 ℃, total reaction time 1.5 h.
The design is done first in an equivalent lumped circuit model,then how to improve the stability of the circuit and lower the noise figure are discussed,and finally it works out a circuit simulation result of a two step LNA with the working passband 1650M~2350M,the gain G>29dB,the gain flatness GF±1dB,noise figure <0.8dB.
The paper deals with the structure and properties of 3 80%C,2 46%Si,0 25%Mn,0 026%S,0 036%P,0 051%Mg,0 022%RE ductile cast iron heat treated at higher temperature through conventional austempering,two step austempering or austempering+tempering. It was found that the heat treat processing zone is narrow/disappeared at higher temperature so that the bainitic ductile cast iron without austenite in the matrix can be obtained.
For (Nd0.8Dyo.2)15Fe62Co15B8, the coercivity lost caused by cracking was certainly restored by two step heat treatment (890℃ × 1 h + 580℃ × 1 h). When an average partical size was about 350 μm, the coercivity reached to 570 kA/m, which is an acceptable level for bonded magnets.
In view of mechanochemistry,in order to fully activate the potential hydraulic activity of clinker and mineral admixture during hydration,the traditional cement grinding process is changed into two step grinding According to this process, 425 # slag cement containing 70% slag and 425R # fly ash cement containing 45% fly ash are made of 525 # clinker from a shaft kiln.
Experimental study on ex vivo expanded hematopoietic stem/progenitor in the two step culture from human umbilical cord blood tra
The effects of hematopoietic stem/progenitor cells (HSPCs) expanded in the two step coculture with human bone marrow mesenchymal stem cells (hMSCs) on the hematopoietic reconstruction of irradiated NOD/SCID mice were studied.
By two step acid-alkali pretreatment and immersing into supersaturated calcification solution, hydroxyapatite (HA) coating was deposited on titanium (Ti) discs.
In this study, aerodynamic sound radiated from a circular cylinder in uniform flow is predicted numerically by the following two step method.
A two step procedure for the synthesis of a novel family of homogeneous and immobilized Ru-complexes containing Schiff bases as O,N-bidentate ligands is described.