TECHNOLOGY FOCUS - POLYMERS - Preferred Composition: The ortho-positioned functional group comprises hydroxyl group, thiol group or amino group. The polymer has fractional free volume (FFV) of 0.15-0.40 and interplanar distance (d-spacing) of 580-800 nm measured by X-ray diffraction. The polymer comprises picopores having full width at half maximum of 10-40 nm measured by positron annihilation lifetime spectroscopy, and has Brunauer Emmett Teller surface area of 100-1000 m2/g. The polyimide is chosen from polyimide of formulae (1-4), its copolymers chosen from formulae (5-8) and/or their copolymers. The thermally rearranged polymer is chosen from polymers of formulae (19-32) or their copolymers. The polyimide is obtained from polyamic acid chosen from formulae (33-40).Ar1=monoaromatic group chosen from tetravalent 6-24C arylene or tetravalent 4-24C heterocyclic group (both optionally substituted), or at least two aromatic groups may combine to form condensed cycle, or are linked by single bond or functional group chosen from O, S, C(=O), S(=O)2, Si(CH3)2, (CH2)p, (CF2)q, C(CH3)2, C(CF3)2 or C(=O)NH, preferably chosen from 17 groups of formulae (i-v), more preferably chosen from 46 groups of formulae (i-1 to i-5);p,q=1-10;Ar2,Ar1'=monoaromatic group chosen from divalent 6-24C arylene or divalent 4-24C heterocyclic group (both optionally substituted), or at least two aromatic groups may combine to form condensed cycle, or are linked by single bond or functional group chosen from O, S, C(=O), S(=O)2, Si(CH3)2, (CH2)p, (CF2)q, C(CH3)2, C(CF3)2 or C(=O)NH, preferably chosen from 16 groups of formulae (vi-x), more preferably chosen from 73 groups of formulae (ii-1 to ii-5);Q=O, S, C(=O), CH(OH), S(=O)2, Si(CH3)2, (CH2)p, (CF2)q, C(CH3)2, C(CF3)2, C(=O)NH, C(CH3)(CF3), or phenylene group optionally substituted by 1-6C alkyl or 1-6 haloalkyl, and is linked with aromatic groups with m-m, m-p, p-m, or p-p positions, more preferably C(CH3)2, C(CF3)2, C(=O), O, S or S(=O)2;Y'=OH, SH, or NH2;n=20-200;m,l=10-400;X1-X4=O, S, C(=O), CH(OH), S(=O)2, Si(CH3)2, (CH2)p, (CF2)q, C(CH3)2, C(CF3)2, C(=O)NH;W1,W2=O, S or C(=O);Z1=O, S, CR1R2 or NR3;Z2,Z3=N or CR4, and are not simultaneously CR4;R1-R4=H or 1-5C alkyl;andY"=O or S.The mol ratio of the repeating unit of formula (1-4) or mol ratio of the repeating unit of formula (5-8) is 0.1:9.9-9.9:0.1. The doped solution contains 10-45 weight% of polyimide, 25-70 weight% of organic solvent and 2-30 weight% of additive, and has viscosity of 2-200 Pa.second. Preferred Process: The imidation is chemical imidation performed at 20-180 degrees C for 4-24 hours, or solution-thermal imidation. The solution-thermal imidation is performed at 100-180 degrees C for 2-30 hours inner solution. The ortho-positioned functional group of polyamic acid is protected before the imidation and the protecting group is removed after the imidation. The solution-thermal imidation is performed using an azeotropic mixture. The heating is performed by increasing the temperature to 400-550 degrees C at rate of 10-30 degrees C/minute maintaining the temperature for 1 minute-1 hour under inert atmosphere.    TECHNOLOGY FOCUS - TEXTILES AND PAPER - Preferred Properties: The hollow fiber comprises dense layer containing picopores at the surface portion. The number of picopores increases towards the surface of the fiber. The 3-dimensional network structure in which at least 2 picopores are 3-dimensionally connected comprises hourglass shaped structure forming a narrow valley at connection portions. The hollow fiber oxygen/nitrogen selectivity of 4 or more, preferably 4-20, carbon dioxide/methane selectivity of 30 or more, preferably 30-80, hydrogen/nitrogen selectivity of 30 or more, preferably 30-80, hydrogen/methane selectivity of 50 or more, preferably 50-90, carbon dioxide/nitrogen selectivity of 20 or more, preferably 20-50 and helium/nitrogen selectivity of 40 or more, preferably 40-120.