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141.
γ-射线辐照对尼龙6纤维结构的影响 总被引:1,自引:0,他引:1
<正> 过去的大多数研究表明,高能射线辐照会引起聚乙烯及聚丙烯等稀烃类聚合物分子链交联及降解,而且会导致结晶度下降。张利华等人最近的研究表明,对于尼龙1010塑料,仅当辐照剂量高到一定程度后,辐照才会破坏结晶。此外,Stowe等人曾经研究过近紫外线对尼龙66纤维结构的影响,结果表明,在空气气氛中的近紫外辐照主要导致尼龙66纤维降解,并使纤维结晶度提高。有关高能射线辐照对高度取向的合成纤维结构及性能的影响的研究尚不多见。本工作将讨论γ-射线对于尼龙6纤维结构的影响。 相似文献
142.
一维链状冠醚配合物:[{Na(18-C-6)}2(H2O)]n[M(SCN)4]n(M=Pd、Pt)的合成与结构 总被引:1,自引:0,他引:1
The reactions of 18-crown-6 with Na2[M(SCN)4] (M= Pd,Pt) were studied and the complex 1 [{Na(18-C-6)}2(H2O)]n[Pd(SCN)4]n and complex 2 [{Na(18-C-6)}2(H2O)]n[Pt(SCN)4]n were characterized by ele-mental analysis, IR and X-ray diffraction analysis. The complexes belong to monoclinic, space group P21/n with cell dimensions, 1:a=1.05734(7),b=1.42250(10),c=1.47762(10) nm,β=107.5330(10)°,V=2.1192(2)nm3,Z=2,Dcalcd=1.460g·cm-3,F(000)=964,R1=0.0406,wR2=0.1264 and 2:a=1.05985(19),b=1.4237(3),c=1.4744(3) nm,β=107. 096(3)°, V=2.1264(7)nm3,Z=2,Dcalcd=1.690g·cm-3,F(000)=1028,R1=0.0292,wR2=0.0859. In the solid state, the complexes 1 and 2 show an one-dimensional chain of [{Na(18-C-6)}2(H2O)]2+ complex cations and [M(SCN)4]2- (M=Pd,Pt) complex anions bridged by Na-N in-teractions. 相似文献
143.
报道了四种不同P/Pd摩尔比的膦化聚2,6-二甲基1,4-苯醚负载把催化剂的加氢和异构化性能;通过XPS、电镜和远红外对催化剂进行了表征;并考察了溶剂和温度对催化剂活性的影响. 相似文献
144.
Krystyna Holderna-Natkaniec Ireneusz Natkaniec Weronika Kasperkowiak Elzbieta Sciesinska Jacek Sciesinski Edward Mikuli 《Journal of Molecular Structure》2006,790(1-3):94-113
FTIR and IINS spectra of 6-Furfurylaminopurine (6-FAP) and 6-Benzylaminopurine (6-BAP) taken at different temperatures have been analysed and compared with the spectra calculated by the ab initio DFT/B3LYP method and the semiempirical PM3 method in the isolated molecule approximation, for the tautomers N3-H, N7-H and N9-H, and dimers with hydrogen bonds. For 6-FAP the best agreement between the calculated and experimental (at 20 K) spectra has been found for the N9-H tautomer, whose structure was established by X-ray diffraction. For 6-BAP the analogous agreement for the N9-H tautomer structure has been poor and much better for the N7-H tautomer. The vibrational spectra calculated for dimers of the molecules studied involved in hydrogen bonds, permitted also an interpretation of the bands whose positions and FWHM in the FTIR spectra changed with temperature. 相似文献
145.
LI Jing-Zhi XUE Si-Jia② LIU Guo-Hua 《结构化学》2006,25(8):903-908
1 INTRODUCTION The acyl ureas are a kind of high biological acti- vity compounds with low toxicity to mammals, birds, fish, amphibians, etc., and significant organic synthe- sis intermediates working extensively as insecticides, pesticides, fungicides and herbicides in agrochemi- cal industry[1~7]. While pyrimidinyl derivatives show excellent biological activities in the development of pesticide, and are used to develop high effective and high select herbicides. For example, pyrimidiny su… 相似文献
146.
簇合物[Fe(DMF)6][W2S6]的合成,结构和性能研究 总被引:4,自引:0,他引:4
以(NH_4)_2WS_4、FeCl_3和NaS_2CNC_5H_(10)为原料,合成出[Fe(DMF)_6][W_2S_6]簇合物,用X射线衍射法测定了晶胞结构.其晶胞参数为a=0.8778(1)nm,b=0.9467(3)nm,c=1.1362(6)nm,α=71.506(1)°,β=74.775(2)°,γ=74.775(2)°,ν=0.84806nm~3,Z=1.晶体结构经块矩阵最小二乘法精修后,最终偏离因子R=0.0811.此外还进行了红外光谱、紫外可见光谱的测定. 相似文献
147.
148.
S-Alkylation of 2-acetamido-9-(2-acetoxyethoxymethyl)-6-oxo-8-thioxopurine was used to synthesize its novel S- and N(7)-substituted derivatives. We have established the effect of the structure of the alkylating agent on the reaction conditions and its regioselectivity. We have shown that the synthesized guanine derivatives can be modified further. 相似文献
149.
Nobuyuki Tanaka 《Journal of Thermal Analysis and Calorimetry》1996,46(3-4):1021-1031
The instantaneous elastic moduli for a nylon-6 monofilament were derived on strain recoveries right after creep, stress relaxation, and rapid elongation,E
c
,E
s
andE
e
, respectively. It was found that during strain recoveryE
s
(>E
e
) andE
e increase monotonically with increasing load,m
1, on the sample. The extrapolated value of Es atm
1=0 g is almost equal to Young's modulus, 4.06 GPa. The value ofE
c also increased with increasingm
1, and atm
1=600 g (1.93 t cm–2) reached about 14 GPa. The endothermic heat change right after creep, stress relaxation or rapid elongation,Q, was negligibly small. For comparison,E
s
,E
c
andQ were also investigated for silicone rubber. It was found thatE
s (53.8 M Pa at the draw ratioD=1.2) decreased abruptly atD=1.3. In the range ofD=1.4–1.9,E
s was only 22.6 MPa. In the case of stress relaxation,Q increased with increasingD from 4 J mol–1 (atD=1.2) to 56 J mol–1 (atD=1.9). FurthermoreE
c (5.58 MPa atm
1=133.8 g (429.4 kg cm–2)) increased gradually with increasing m1 and attained 16.6 MPa atm
1=548.4 g (1.76 t cm–2). In the case of creep,Q was in the range of 0–11.5 J mol–1 and larger when larger loads,m
2 were removed during the later stages of creep.Dedicated to Professor Bernhard Wunderlich on the occasion of his 65th birthdayThe author wishes to thank Mr. Keizi Igarashi and Mr. Tetsuya Yasui for helping in the experiments. 相似文献
150.
Treatment of 1-alkyl-4,5-dichloro-3-nitropyridazin-6-one with C-nucleophiles and with ambident nucleophiles (2-azahetarylacetonitriles)
leads to a selective substitution of a chorine atom by the quaternary carbon atom of the carbanion formed from a substituted
acetonitrile. The pKa of the CH-acid 2-(1-alkyl-5-chloro-3-nitro-6-oxo-1,6-dihydro-4-pyridazinyl)malononitrile was determined by potentiometric
titration. Reaction of 2-(1-alkyl-5-chloro-3-nitro-6-oxo-1,6-dihydro-4-pyridazinyl)-2-hetarylacetonitriles with primary amines
gives 6,7-dihydro-1H-pyrrolo[2,3-d]pyridazin-7-ones.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 556–564, April, 2006. 相似文献