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1.
The present paper deals with improvement in disperse dyeability as well as imparting of cationic dyeablility to difficultly dyeable polypropylene by a melt blending technique. Isotactic polypropylene (PP) was blended with fibre grade polybutylene terephthalate (PBT), cationic dyeable polyethylene terephthalate (CDPET) and polystyrene (PS), individually. The resulting binary blends were spun and drawn into fibres at draw ratio 2, 2.5, and 3. The compatibility of blends, structural changes of fibres in terms of X-ray crystallinity, relative crystallinity, sonic modulus, birefringence and thermal stability were examined. The blended fibres were found to be disperse dyeable by the conventional method of high temperature and high pressure dyeing. And this dyeability increased with increase in the level of substitution. PP/CDPET blend also exhibited dyeablility with cationic dyes in addition to that with disperse dyes. The optimum level of blending was predicted keeping in view of tenacity and thermal stability of melt blend fibres. The wash fastness properties of the dyed fibres were found to be of high rate.  相似文献   
2.
Radioactively labeled iron (59Fe) was used to study differential uptake in sorghum plants in the recovery stage of chlorosis. Radio-labeled 59Fe was supplied through root feeding in nutrient solution experiment (48 hrs, pH 6.2) to non-chlorotic and chlorotic plants. Chlorotic plants were further treated with foliar spray [ferrous sulfate (FeSO4), FeSO4 + thiourea (TU), FeSO4 + citric acid (CA), FeSO4 + thioglycollic acid (TGA)] to study the uptake of radio-labeled 59Fe through root feeding during recovery process of chlorosis. Under iron deficiency, the differential uptake of 59Fe was markedly increased in leaves and stem of chlorotic control (-Fe) sorghum plants as compared to non-chlorotic control (+Fe) and foliar sprayed (FeSO4, FeSO4 + TU, FeSO4 + CA, and FeSO4 + TGA) plants. The lowest uptake of 59Fe was observed in younger leaves (24.33 nmol, g?1 fresh weight h?1) and stem (1.98 nmol, g?1 fresh weight h?1) of non-chlorotic control followed by foliar sprayed plants in comparison to chlorotic control, respectively. Similarly less 59Fe uptake was observed in the older leaves of FeSO4 + CA sprayed (21.70 nmol, g?1 fresh weight h?1) plants in comparison to chlorotic control (35.60 nmol, g?1 fresh weight h?1). The highest differential 59Fe uptake through nutrient medium was in the roots of plants, which were foliar sprayed with FeSO4 along with TU. The role of iron alone and along with citric acid and thiol compounds is discussed in recovery of chlorosis.  相似文献   
3.
The physiology of NaCl induced stress was studied in two prop species, cowpea and 4 cultivars of tobacco one of which (Jayashree) is salt sensitive. It was found that the growth of all the cvs of tobacco was reduced by the presence of NaCl (100 mH) in the nutrient medium. While the fresh wt per unit area of the leaves of salt‐tolerant tobacco cv. I and PV‐7 (Nicotiana tabacum L.) and MPS‐219 (N. rustica L.) was increased’ significantly, it was decreased in the salt‐sensitive Jayashree. The dry wt per unit leaf area was decreased much more in I, PV‐7 and J than in NPS‐219. The total chlorophyll was reduced in all and more so in Jayashree.

The relative turgidity % was found to decrease in the primary leaves of cowpea (Vigna unguiculata L.) in the first 6 days of treatment with 100 mM NaCl in the nutrient medium while the decrease was less significant in the first and and second trifoliate leaves, showing that there was readjustment with growth of the plant to salinity. The 14C fixation in the leaf disks of cowpea grown in NaCl was much less than in the control plants. The studies reveal that there is a general reduction in the growth of both tobacco and cowpea following NaCl treatment and this effect is due to a decrease in the total chlorophyll and a reduced rate of photosynthesis.  相似文献   
4.
Two sorghum (Sorghum bicolor L. Moench) hybrids CSH‐10 and ‐ 11 and their parent cultivars 296‐A, SB‐1055 and MR‐715 were examined for their tolerance to Fe‐deficiency stress, and also Fe uptake. It was observed that there was greater reduction of pH of the nutrient media and more rapid recovery from chlorosis only in the female parent 296‐A, and to some degree in the hybrids, but not in the male parents. The results indicated that Fe uptake‐translocation were inversely related to their Fe stress tolerance.  相似文献   
5.
Vicolides A–D (0.2–2000 ppm) from Pentanema indicum showed antifeedant activity against Euproctes fraterna and Pericallia ricini V stage larvae.  相似文献   
6.
Type I interferons (IFN) are important mediators of the host defense against viral infections in mammals. In humans multiple subtypes of IFN-alpha exist, most of which possess antiviral activity. Little is known about the type I IFN genes in cats and the role they may play in feline immunological responses to viruses. We have isolated cDNAs encoding five feline IFN-alpha (feIFN) subtypes that share from 95 to 99% amino acid sequence identity. FeIFN-alpha5 has five additional amino acids inserted at position 139, which are not present in the other four subtypes. Sequence identity of the feIFN proteins encoded by the five clones compared to human IFN-alpha2 is approximately 60%. Unlike most of the human subtypes, each of the five feline IFN sequences has an N-glycosylation recognition site. Expression of all five feIFN-alpha subtypes in Chinese hamster ovary (CHO) cells was confirmed by Western blot analysis, and all resulting proteins were glycosylated. The antiviral activity of each feIFN-alpha subtype produced in transiently transfected CHO cell cultures was tested in vitro. In addition, subtype feIFN-alpha6 was expressed in the yeast, Pichia pastoris. The resulting secreted mature recombinant protein was purified and demonstrated significant antiviral activity and induction of 2',5'-oligoadenylate synthetase activity in vitro.  相似文献   
7.
Sorghum (Sorghum bicolor L. Moench) cv. CSH‐7, an Fe‐efficient hybrid was grown and subjected to Fe‐deficiency stress. The nutrient medium was extracted for isolation of reductant chemicals. By means of thin layer chromatography, I.R. spectrum and HPLC analysis, dibutyl phthalate was identified as the principal component. This chemical was not found in the nutrient medium extracted before the onset of chlorosis or in that after the plants recovered from chlorosis. Furthermore, synthetic dibutyl phthalate and that obtained from the exudate when supplied to the nutrient medium caused greening of chlorotic sorghum in 24 hours. Evidence that the root medium of the Fe‐efficient sorghum can induce recovery of an Fe‐inefficient sorghum grown together, has also been obtained. It is concluded that dibutyl phthalate released by the Fe‐efficient sorghum subjected to stress, is responsible for making Fe available for utilisation. The mechanism of action of dibutyl phthalate on chlorosis recovery is still an open question.  相似文献   
8.
The jute (Corchorus capsularis L.) cv. 3RC‐212 which is Fe‐efficient, was subjected to Fe‐deficiency stress, and the nutrient medium was examined for chemicals, when the plants became chlorotic and the pH was lowered to about 4. While phenolic acids could not be detected, DBP (dibutyl phthalate) was identified in the extract by means of TLC and HPLC. The effect of DBP and caffeic acid was studied in JRC‐212 and DBP was found to cause recovery of the plants from chlorosis in 5 days. The chemicals, PA (phthalic acid), a derivative of DBP (50 mg/1) were supplied to chlorotic plants of JRO‐632, an Fe‐inefficient jute cultivar, and both the chemicals were effective in chlorosis recovery. PA application caused more rapid greening than DBP.

Jute is the second crop species in which DBP is identified in the root exudate. The detection of DBP was first recorded in sorghum CSH‐7.  相似文献   

9.
The absorption and transport of Na and Cl from 0.1 mM and 10 mM 22Na labelled NaCl or 36Cl labelled KCl were examined in 15 days old seedlings of 3 cultivars of rice differing in their tolerance to salinity. Furthermore, the effects of 10, 100 and 1000 ppm (N)2S on their uptake were studied. It was found that in general, the salt‐tolerant cultivars BR and PNL‐1 absorbed more Na and translocated a lesser proportion of it to the shoot, compared to the salt‐sensitive IR‐8, from 0.1 mM NaCl. The presence of (N)2S reduced the uptake of Na in all the cultivars. It was also found that the presence of 100 ppm K, KN or NNreduced Na absorption from 0.1 mM NaCl significantly in all the cultivars, and the translocation to shoot in BR‐ Chloride transport from 0.1 mM NaCl was reduced by (N)2S in all the cultivars. The 3 cultivars differed significantly in the rates of absorption and transport of Na and Cl. The results indicate that PNL‐1 which is a cross of IR‐8 X BR, has inherited the salt tolerance trait from BR. Lower rates of Na translocation to the shoot can be used as an index of salt tolerance in rice.  相似文献   
10.
The absorption of Mo by the roots and. transport to the shoot of intact seedlings of a sorghum hybrid and its parent cultivars were measured for 3 h from 10 to 100 μmol ammonium molybdate. The patterns of absorption revealed hybrid vigour and the hybrid followed the patterns of the male- parent 168. Studies on the effects of different amounts of Mo on the nitrate reductase activity also showed the occurrence of hybrid vigour in the- hybrid CSH-7.  相似文献   
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